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  • 126651.
    Rovira, Marc
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Process Technology.
    Engvall, Klas
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Process Technology.
    Duwig, Christophe
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Process Technology.
    Sensitivity analysis of an ammonium salt formation model applied to pollutant removal in marine diesel exhaust gasesManuscript (preprint) (Other academic)
    Abstract [en]

    This study presents the sensitivity analysis of the aerosol model for ammonium salt particle formation from NOx and SOx pollutants for low-temperature gas cleaning applications developed by Olenius et al. (2021). Starting from the acid gases derived from NOx and SOx (i.e. HNO3 and H2SO4), the numerical model simulates different particle growth phenomena as the acids react with ammonia (NH3). In the present study, the aerosol model uncertainty is analyzed systematically for the first time through a global sensitivity analysis employing the Sobol' method. The first- and total-order effects of five different input variables on model outputs such as particle size distribution, pollutant removal effectiveness, ammonia slip, and total run time are reported. Furthermore, the range of input parameters for which the model is tested is made to emulate the realistic operations experienced by low-speed two-stroke marine diesel engine ships burning fuel with high sulfur content. The sources of uncertainty are reviewed in detail to provide a holistic yet more complete view of the knowledge gaps in the particle conversion process.

  • 126652.
    Rovira Sacie, Marc
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Process Technology.
    Engvall, Klas
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Process Technology.
    Duwig, Christophe
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Process Technology.
    Sensitivity analysis of an ammonium salt formation model applied to pollutant removal in marine diesel exhaust gases2023In: Fuel, ISSN 0016-2361, E-ISSN 1873-7153, Vol. 332, article id 126001Article in journal (Refereed)
    Abstract [en]

    Elevated exposure to airborne pollutants such as NOx and SOx is known to be damaging to human health. A current approach to deal with such harmful gases is to trap them in ammonium salt particles. The present study presents the sensitivity analysis of the aerosol model for ammonium salt particle formation from NOx and SOx for low-temperature gas cleaning applications developed by Olenius et al. (2021). Starting from the acid gases derived from NOx and SOx (i.e. HNO3 and H2SO4), the model simulates the particle growth phenomena as the acids react with ammonia (NH3). This work presents, for the first time, a global sensitivity analysis of the aerosol model uncertainty. The first-and total-order effects of five different input variables on model outputs such as particle size distribution, pollutant removal effectiveness, ammonia slip, and total run time are reported. Furthermore, the range of input parameters for which the model is tested is made to emulate the conditions experienced by two-stroke marine diesel engine ships. Sources of uncertainty are reviewed in detail to provide a complete view of the knowledge gaps in the particle conversion process. For the conditions studied, we report that variations in particle sizes are influenced by HNO3, H2SO4 and temperature. Similarly, the degree of ammonia slip was observed to be driven by temperature and the ammonia ratio. Additionally, the removal efficiency of HNO3 was reported to be very high (above 99%) for the vast majority of conditions tested, and was not significantly influenced by the concentration of H2SO4. Finally, the model run time variability was observed to depend mainly on variations in temperature, relative humidity and the ammonia ratio.

  • 126653.
    Rovira Torres, Marcelo
    KTH, School of Architecture and the Built Environment (ABE), Architecture.
    Enhet / Helhet2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Unit and Unity 

    By: Marcelo Rovira Torres

    Where does one begin when a bathhouse is in the works? Where did bathhouses originate? Perhaps it was by the sea, when the autumn chill made the water unbearable and people searched for a place where they could swim no matter the climate. Three bathing houses in three Swedish cities, Gothenburg, Malmö and Luleå built during ‘Folkhemsbygget’ in the first half of the 20th century were analysed. There, it was clear that the main focus lay on exercise and the swimming pool for aquatic sports was the buildings undeniable centerpiece. The sauna and ablution seem to have a secondary role, but the function is just as important. This project is about distilling the meeting between the bathhouse’s two main functions, exercise and ablution, to peel away all the excess and find architecture that comes as close to the buildings core as possible. 

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    MarceloRoviraTorresKandidatArkitektur
  • 126654. Rovira-Esteva, M.
    et al.
    Natarajan Arul, Murugan
    KTH, School of Biotechnology (BIO), Theoretical Chemistry and Biology.
    Pardo, L. C.
    Busch, S.
    Tamarit, J. Ll
    Cuello, G. J.
    Bermejo, F. J.
    Differences in first neighbor orientation behind the anomalies in the low and high density trans-1,2-dichloroethene liquid2012In: Journal of Chemical Physics, ISSN 0021-9606, E-ISSN 1089-7690, Vol. 136, no 12, p. 124514-Article in journal (Refereed)
    Abstract [en]

    Trans-1,2-dichloroethene (HClC=CClH) has several structural and dynamic anomalies between its low-and high-density liquid, previously found through neutron scattering experiments. To explain the microscopic origin of the differences found in those experiments, a series of molecular dynamics simulations were performed. The analysis of molecular short-range order shows that the number of molecules in the first neighbor shell is 12 for the high-density liquid and 11 for the low-density one. It also shows that the angular position of the center of mass of the first neighbor is roughly the same although the molecular orientation is not. In both liquids the first neighbor and its reference molecule arrange mainly in two configurations, each being the most probable in one of the liquids. First neighbors in the configuration that predominates in the high-density liquid tend to locate themselves closer to the reference molecule, an evidence that they are more strongly bonded. This arrangement facilitates a better packing of the rest of molecules in the first neighbor shell so that on average an additional molecule can be included, and is proposed to be the key in the explanation of all the observed anomalies in the characteristics of both liquids.

  • 126655.
    Rovsnik, Urska
    et al.
    Stockholm Univ, Dept Biochem & Biophys, Solna, Sweden..
    Lim, Victoria
    Univ Calif Irvine, Irvine, CA USA..
    Blau, Christian
    KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Howard, Rebecca J.
    Stockholm Univ, Dept Biochem & Biophys, Solna, Sweden..
    Lindahl, Erik
    Stockholm Univ, Dept Biochem & Biophys, Solna, Sweden..
    Cryo-EM Structure Determination and Model Fitting of the Proton-Gated Ligand-Gated Ion Channel glic at Multiple pH States2020In: Biophysical Journal, ISSN 0006-3495, E-ISSN 1542-0086, Vol. 118, no 3, p. 581A-582AArticle in journal (Other academic)
  • 126656. Rovsnik, Urska
    et al.
    Zhuang, Yuxuan
    Forsberg, Bjorn
    Carroni, Marta
    Axelsson, Linnea
    Blau, Christian
    KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Howard, Rebecca J.
    Lindahl, Erik R.
    Heterogeneous Populations of Ligand-Gated Ion Channel, GLIC, Revealed by Cryo-Electron Microscopy and Simulations2021In: Biophysical Journal, ISSN 0006-3495, E-ISSN 1542-0086, Vol. 120, no 3, p. 192A-192AArticle in journal (Other academic)
  • 126657.
    Rovsnik, Urska
    et al.
    Stockholm Univ, Dept Biochem & Biophys, Sci Life Lab, Solna, Sweden..
    Zhuang, Yuxuan
    Stockholm Univ, Dept Biochem & Biophys, Sci Life Lab, Solna, Sweden..
    Forsberg, Bjorn O.
    Stockholm Univ, Dept Biochem & Biophys, Sci Life Lab, Solna, Sweden.;Univ Oxford, Wellcome Ctr Human Genet, Div Struct Biol, Oxford, England..
    Carroni, Marta
    Stockholm Univ, Dept Biochem & Biophys, Sci Life Lab, Solna, Sweden..
    Yvonnesdotter, Linnea
    Stockholm Univ, Dept Biochem & Biophys, Sci Life Lab, Solna, Sweden..
    Howard, Rebecca J.
    Stockholm Univ, Dept Biochem & Biophys, Sci Life Lab, Solna, Sweden..
    Lindahl, Erik
    KTH, School of Engineering Sciences (SCI), Applied Physics, Biophysics. KTH, Centres, Science for Life Laboratory, SciLifeLab. Stockholm Univ, Dept Biochem & Biophys, Sci Life Lab, Solna, Sweden..
    Dynamic closed states of a ligand-gated ion channel captured by cryo-EM and simulations2021In: Life Science Alliance, E-ISSN 2575-1077, Vol. 4, no 8, article id e202101011Article in journal (Refereed)
    Abstract [en]

    Ligand-gated ion channels are critical mediators of electrochemical signal transduction across evolution. Biophysical and pharmacological characterization of these receptor proteins relies on high-quality structures in multiple, subtly distinct functional states. However, structural data in this family remain limited, particularly for resting and intermediate states on the activation pathway. Here, we report cryo-electr on microscopy (cryo-EM) structures of the proton-activated Gloeobacter violaceus ligandgated ion channel (GLIC) under three pH conditions. Decreased pH was associated with improved resolution and side chain rearrangements at the subunit/domain interface, particularly involving functionally important residues in the beta 1-beta 2 and M2-M3 loops. Molecular dynamics simulations substantiated flexibility in the closed-channel extracellular domains relative to the transmembrane ones and supported electrostatic remodeling around E35 and E243 in proton-induced gating. Exploration of secondary cryoEM classes further indicated a low-pH population with an expanded pore. These results allow us to define distinct protonation and activation steps in pH-stimulated conformational cycling in GLIC, including interfacial rearrangements largely conserved in the pentameric channel family.

  • 126658.
    Rowan, Neil
    et al.
    Athlone Institute of Technology.
    Buckley, Jeffrey
    KTH, School of Industrial Engineering and Management (ITM). Athlone Institute of Technology.
    Seery, Niall
    Athlone Institute of Technology.
    Murray, Niall
    Athlone Institute of Technology.
    Blending immersive and educational technologies to inform sustainability and diversification of workforce training through machine interface learning using sterilization technologies as model – quo vadis?2019Conference paper (Refereed)
  • 126659. Rowbotham, S. E.
    et al.
    Pinchbeck, J. L.
    Anderson, G.
    Bourke, B.
    Bourke, M.
    Gasser, T. Christian
    KTH, School of Engineering Sciences (SCI), Solid Mechanics (Dept.).
    Jaeggi, R.
    Jenkins, J. S.
    Moran, C. S.
    Morton, S. K.
    Reid, C. M.
    Velu, R.
    Yip, L.
    Moxon, J. V.
    Golledge, J.
    Inositol in the MAnaGemENt of abdominal aortic aneurysm (IMAGEN): Study protocol for a randomised controlled trial2017In: Trials, E-ISSN 1745-6215, Vol. 18, no 1, article id 547Article in journal (Refereed)
    Abstract [en]

    Background: An abdominal aortic aneurysm (AAA) is a focal dilation of the abdominal aorta and is associated with a risk of fatal rupture. Experimental studies suggest that myo-inositol may exert beneficial effects on AAAs through favourable changes to biological pathways implicated in AAA pathology. The aim of the Inositol in the MAnaGemENt of abdominal aortic aneurysm (IMAGEN) trial is to assess if myo-inositol will reduce AAA growth. Methods/design: IMAGEN is a multi-centre, prospective, parallel-group, randomised, double-blind, placebo-controlled trial. A total of 164 participants with an AAA measuring ≥ 30 mm will be randomised to either 2 g of myo-inositol or identical placebo twice daily for 12 months. The primary outcome measure will be AAA growth estimated by increase in total infrarenal aortic volume measured on computed tomographic scans. Secondary outcome measures will include AAA diameter assessed by computed tomography and ultrasound, AAA peak wall stress and peak wall rupture index, serum lipids, circulating AAA biomarkers, circulating RNAs and health-related quality of life. All analysis will be based on the intention-to-treat principle at the time of randomisation. All patients who meet the eligibility criteria, provide written informed consent and are enrolled in the study will be included in the primary analysis, regardless of adherence to dietary allocation. Discussion: Currently, there is no known medical therapy to limit AAA progression. The IMAGEN trial will be the first randomised trial, to our knowledge, to assess the value of myo-inositol in limiting AAA growth.

  • 126660. Rowe, W.
    et al.
    Karlsson, Johan
    KTH, School of Engineering Sciences (SCI), Mathematics (Dept.), Optimization and Systems Theory.
    Xu, L.
    Glentis, G. -O
    Li, J.
    SAR imaging in the presence of spectrum notches via fast missing data IAA2013In: Automatic Target Recognition XXIII, SPIE - International Society for Optical Engineering, 2013, p. UNSP 87440X-Conference paper (Refereed)
    Abstract [en]

    A synthetic aperture radar system operating in congested frequency bands suffers from radio frequency inter- ference (RFI) from narrowband sources. When RFI interference is suppressed by frequency notching, gaps are introduced into the fast time phase history. This results in a missing data spectral estimation problem, where the missing data increases sidelobe energy and degrades image quality. The adaptive spectral estimation method Iterative Adaptive Approach (IAA) has been shown to provide higher resolution and lower sidelobes than comparable methods, but at the cost of higher computationally complexity. Current fast IAA algorithms reduce the computational complexity using Toeplitz/Vandermonde structures, but are not applicable for missing data cases because these structures are lost. When the number of missing data samples is small, which often is the case in SAR with RFI, we use a low rank completion to restore the Toeplitz/Vandermonde structures. We show that the computational complexity of the proposed algorithm is considerably lower than the state-of-the-art and demonstrate the utility on a simulated frequency notched SAR imaging problem.

  • 126661.
    Rowe, W. R.
    et al.
    Univ Bath, Ctr Photon & Photon Mat, Dept Phys, Bath BA2 7AY, Avon, England..
    Gorbach, A. , V
    Fergestad, Halvor
    KTH, School of Engineering Sciences (SCI), Applied Physics.
    Gallo, Katia
    KTH, School of Engineering Sciences (SCI), Applied Physics.
    Skryabinl, D. , V
    Gap solitons supported by mode hybridisation in Lithium Niobate nano-waveguides2021In: 2021 Conference On Lasers And Electro-Optics Europe & European Quantum Electronics Conference (Cleo/Europe-Eqec), Institute of Electrical and Electronics Engineers (IEEE) , 2021Conference paper (Refereed)
    Abstract [en]

    Nano-waveguide platforms have been developed over the past decade providing strong field enhancement and allowing precise control of modal dispersion [1] . Such nano-waveguides produced from materials with strong quadratic (χ (2) ) nonlinearity make excitation of χ (2) temporal solitons feasible [2] . Compared with Kerr solitons, χ (2) solitons have tighter dispersion criteria making nano-waveguides the only practical method for their observation [2] , [3] . As seen in previous work in photonic crystal fibres [4] , mode hybridisation, which occurs generally in waveguides with rectangular (or close to rectangular) cross-section, provides conditions to study novel types of soliton and their dynamics.

  • 126662. Rowe, W. R.
    et al.
    Gorbach, A. V.
    Fergestad, Halvor
    KTH, School of Engineering Sciences (SCI), Applied Physics, Quantum and Biophotonics.
    Gallo, Katia
    KTH, School of Engineering Sciences (SCI), Applied Physics, Quantum and Biophotonics.
    Skryabin, D. V.
    Gap solitons supported by mode hybridisation in lithium niobate nanowaveguides2021In: Optics InfoBase Conference Papers, Optica Publishing Group , 2021Conference paper (Refereed)
  • 126663. Rowley, Clarence
    et al.
    Mezic, Igor
    Bagheri, Shervin
    KTH, School of Engineering Sciences (SCI), Mechanics.
    Schlatter, Philipp
    KTH, School of Engineering Sciences (SCI), Mechanics.
    Henningson, Dan S.
    KTH, School of Engineering Sciences (SCI), Mechanics.
    Reduced-order models for flow control: balanced models and Koopman modes2010In: Seventh IUTAM Symposium on Laminar-Turbulent Transition / [ed] P. Schlatter and D. S. Henningson, 2010, p. 43-50Conference paper (Refereed)
    Abstract [en]

    This paper addresses recent developments in model-reduction techniques applicable to fluid flows The main goal is to obtain low-order models tractable enough to be used for analysis and design of feedback laws for flow control, while retaining the essential physics. We first give a brief overview of several model reduction techniques. including Proper Orthogonal Decomposition [3], balanced truncation [8, 9], and the related Eigensystem Realization Algorithm [5, 6], and discuss strengths and weaknesses of each approach We then describe a new method for analyzing nonlinear flows based on spectral analysis of the Koopman operator a linear operator defined for any nonlinear dynamical system We show that, for an example of a Jet in crossflow, the resulting Koopman modes decouple the dynamics at different timescales more effectively than POD modes, and capture the relevant frequencies more accurately than lineal stability analysis

  • 126664. Rowley, Clarence W.
    et al.
    Mezic, Igor
    Bagheri, Shervin
    KTH, School of Engineering Sciences (SCI), Mechanics. KTH, School of Engineering Sciences (SCI), Centres, Linné Flow Center, FLOW.
    Schlatter, Philipp
    KTH, School of Engineering Sciences (SCI), Mechanics. KTH, School of Engineering Sciences (SCI), Centres, Linné Flow Center, FLOW.
    Henningson, Dan S.
    KTH, School of Engineering Sciences (SCI), Mechanics. KTH, School of Engineering Sciences (SCI), Centres, Linné Flow Center, FLOW.
    Spectral analysis of nonlinear flows2009In: Journal of Fluid Mechanics, ISSN 0022-1120, E-ISSN 1469-7645, Vol. 641, p. 115-127Article in journal (Refereed)
    Abstract [en]

    We present a technique for describing the global behaviour of complex nonlinear flows by decomposing the flow into modes determined from spectral analysis of the Koopman operator, an infinite-dimensional linear operator associated with the full nonlinear system. These modes, referred to as Koopman modes, are associated with a particular observable, and may be determined directly from data (either numerical or experimental) using a variant of a standard Arnoldi method. They have an associated temporal frequency and growth rate and may be viewed as a nonlinear generalization of global eigenmodes of a linearized system. They provide an alternative to proper orthogonal decomposition, and in the case of periodic data the Koopman modes reduce to a discrete temporal Fourier transform. The Arnoldi method used for computations is identical to the dynamic mode decomposition recently proposed by Schmid & Sesterhenn (Sixty-First Annual Meeting of the APS Division of Fluid Dynamics, 2008), so dynamic mode decomposition can be thought of as an algorithm for finding Koopman modes. We illustrate the method on an example of a jet in crossflow, and show that the method captures the dominant frequencies and elucidates the associated spatial structures.

  • 126665.
    Rowshanzadeh, Reza
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Performance and cost evaluation of Organic Rankine Cycle at different technologies2010Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
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    FULLTEXT01
  • 126666.
    Roxenhag, Anders
    KTH, Superseded Departments (pre-2005), Teleinformatics.
    VoIP and IPSec2000Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    There are several problems with getting Voice over IP (VoIP) protocols to work through Firewalls and Network Address Translators (NAT). Many Internet drafts discuss the issues and different solutions are suggested. One solution is to use Virtual Private Networks (VPN) for VoIP transport, which is explored in this thesis.

    The standard architecture used for implementing VPNs is the Internet Protocol Security Protocol (IPSec). IPSec and NAT have some fundamental incompatibilities and are hard to get to work together. Certain set-ups are feasible to get to work through proper configuration and the right use of protocols and modes. For certain scenarios though, new mechanisms are needed. Such mechanisms are proposed in different Internet drafts and these are discussed in this report.

    The solution discussed in this thesis includes transporting VoIP over IPSec. This solution solves some problems, introduces some new and put higher requirements on network configuration.

  • 126667.
    Roxhagen, Jimmi
    KTH, School of Industrial Engineering and Management (ITM), Applied Mechanical Engineering (KTH Södertälje).
    Vidareutveckling av termoformningsmaskin2018Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In the current situation Plastic Produkter AB uses thermoforming machines for handling semi-finished products of thermoplastics. A machine they manufactured and also sold to different kinds of customers. The original machine was manufactured in a simple design only to cope with the need to bend different work pieces. Since the market and the development of different methods have developed, there is an interest in further developing the current thermoforming machine for semimanufactured thermoplastics.

    In the current version the user is required to manually switch the machine between different types of operations, certain efficiency and improvement is required, which facilitates the use of the machine for the user. The task of this project has therefor been to further develop the thermoforming machine by optimizing its process, but also automating different types of distance measurement regulations between key parts of the thermoforming machine. In order to arrive at a satisfactory result, various investigations have taken place, as well as the facts underlying the development of the different concepts that can contribute to a competitive machine. From these, the most promising concept has been developed through different types of matrices as well as discussions with users and company representatives.

    The result was a further development through a modification of the current thermoforming machine through three different concepts. In these concepts, great focus is on upgrading the thermoforming machine to facilitate the user and reduce the different manual moments required at present for certain types of switches and also to improve the performance of the thermoforming machine from the work piece.

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    fulltext
  • 126668.
    Roxhed, Niclas
    KTH, School of Electrical Engineering (EES), Microsystem Technology.
    A Fully Integrated Microneedle-based Transdermal Drug Delivery System2007Doctoral thesis, comprehensive summary (Other scientific)
    Abstract [en]

    Patch-based transdermal drug delivery offers a convenient way to administer drugs without the drawbacks of standard hypodermic injections relating to issues such as patient acceptability and injection safety. However, conventional transdermal drug delivery is limited to therapeutics where the drug can diffuse across the skin barrier. By using miniaturized needles, a pathway into the human body can be established which allow transport of macromolecular drugs such as insulins or vaccines. These microneedles only penetrate the outermost skin layers, superficial enough not to reach the nerve receptors of the lower skin. Thus, microneedle insertions are perceived as painless.

    The thesis presents research in the field of microneedle-based drug delivery with the specific aim of investigating a microneedle-based transdermal patch concept. To enable controllable drug infusion and still maintain an unobtrusive and easy-to-use, patch-like design, the system includes a small active dispenser mechanism. The dispenser is based on a novel thermal actuator consisting of highly expandable microspheres. When actuated, the microspheres expand into a liquid reservoir and, subsequently, dispense stored liquid through outlet holes.

    The microneedles are fabricated in monocrystalline silicon by Deep Reactive Ion Etching. The needles are organized in arrays situated on a chip. To allow active delivery, the microneedles are hollow with the needle bore-opening located on the side of the needle. This way, the needle can have a sharp and well-defined needle tip. A sharp needle is a further requirement to achieve microneedle insertion into skin by hand.

    The thesis presents fabrication and evaluation of both the microneedle structure and the transdermal patch as such. Issues such as penetration reliability, liquid delivery into the skin and microneedle packaging are discussed. The microneedle patch was also tested and studied in vivo for insulin delivery. Results show that intradermal administration with microneedles give rise to similar insulin concentration as standard subcutaneous delivery with the same dose rate.

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    FULLTEXT01
  • 126669.
    Roxhed, Niclas
    KTH, School of Electrical Engineering (EES), Microsystem Technology.
    Microneedle Fabrication and Challenges on a New Drug Administration Standard2010Conference paper (Refereed)
  • 126670.
    Roxhed, Niclas
    et al.
    KTH, School of Electrical Engineering and Computer Science (EECS), Intelligent systems, Micro and Nanosystems.
    Bendes, Annika
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Protein Science, Affinity Proteomics.
    Dale, Matilda
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Protein Science, Affinity Proteomics. KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Mattsson, Cecilia
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Protein Science, Affinity Proteomics.
    Hanke, Leo
    Karolinska Inst, Dept Microbiol Tumor & Cell Biol, Solna, Sweden..
    Dodig-Crnkovic, Tea
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Protein Science, Affinity Proteomics. KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Christian, Murray
    Karolinska Inst, Dept Microbiol Tumor & Cell Biol, Solna, Sweden..
    Meineke, Birthe
    Karolinska Inst, Sci Life Lab, Dept Med Biochem & Biophys, Div Genome Biol, Solna, Sweden.;Karolinska Inst, Ming Wai Lau Ctr Reparat Med, Stockholm Node, Solna, Sweden..
    Elsasser, Simon
    Karolinska Inst, Sci Life Lab, Dept Med Biochem & Biophys, Div Genome Biol, Solna, Sweden.;Karolinska Inst, Ming Wai Lau Ctr Reparat Med, Stockholm Node, Solna, Sweden..
    Andrell, Juni
    Stockholm Univ, Dept Biochem & Biophys, Sci Life Lab, Solna, Sweden..
    Havervall, Sebastian
    Danderyd Hosp, Karolinska Inst, Dept Clin Sci, Div Internal Med, Danderyd, Sweden..
    Thalin, Charlotte
    Danderyd Hosp, Karolinska Inst, Dept Clin Sci, Div Internal Med, Danderyd, Sweden..
    Eklund, Carina
    Karolinska Univ Hosp, Karolinska Univ Lab, Stockholm, Sweden..
    Dillner, Joakim
    Karolinska Univ Hosp, Karolinska Univ Lab, Stockholm, Sweden..
    Beck, Olof
    Karolinska Inst, Dept Clin Neurosci, Stockholm, Sweden..
    Thomas, Cecilia E.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Protein Science, Affinity Proteomics.
    McInerney, Gerald
    Karolinska Inst, Dept Microbiol Tumor & Cell Biol, Solna, Sweden..
    Hong, Mun-Gwan
    KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Murrell, Ben
    Karolinska Inst, Dept Microbiol Tumor & Cell Biol, Solna, Sweden..
    Fredolini, Claudia
    KTH, Centres, Science for Life Laboratory, SciLifeLab. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Protein Science, Affinity Proteomics.
    Schwenk, Jochen M.
    KTH, Centres, Science for Life Laboratory, SciLifeLab. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Protein Science, Affinity Proteomics.
    Multianalyte serology in home-sampled blood enables an unbiased assessment of the immune response against SARS-CoV-22021In: Nature Communications, E-ISSN 2041-1723, Vol. 12, no 1, article id 3695Article in journal (Refereed)
    Abstract [en]

    Serological testing is essential to curb the consequences of the COVID-19 pandemic. However, most assays are still limited to single analytes and samples collected within healthcare. Thus, we establish a multianalyte and multiplexed approach to reliably profile IgG and IgM levels against several versions of SARS-CoV-2 proteins (S, RBD, N) in home-sampled dried blood spots (DBS). We analyse DBS collected during spring of 2020 from 878 random and undiagnosed individuals from the population in Stockholm, Sweden, and use classification approaches to estimate an accumulated seroprevalence of 12.5% (95% CI: 10.3%-14.7%). This includes 5.4% of the samples being IgG(+)IgM(+) against several SARS-CoV-2 proteins, as well as 2.1% being IgG(-)IgM(+) and 5.0% being IgG(+)IgM(-) for the virus' S protein. Subjects classified as IgG(+) for several SARS-CoV-2 proteins report influenza-like symptoms more frequently than those being IgG(+) for only the S protein (OR=6.1; p<0.001). Among all seropositive cases, 30% are asymptomatic. Our strategy enables an accurate individual-level and multiplexed assessment of antibodies in home-sampled blood, assisting our understanding about the undiagnosed seroprevalence and diversity of the immune response against the coronavirus. Here, Roxhed et al. develop a multiplexed approach to screen IgG and IgM levels against several SARS-CoV-2 proteins in home-sampled dried blood spots and estimate seroprevalence of 12.5% in Stockholm in spring of 2020.

  • 126671.
    Roxhed, Niclas
    et al.
    KTH, School of Electrical Engineering (EES), Microsystem Technology.
    Gasse, Christian
    KTH, School of Engineering Sciences (SCI), Solid Mechanics (Dept.).
    Griss, Patrick
    KTH, School of Electrical Engineering (EES), Microsystem Technology.
    Holzapfel, Gerhard
    KTH, School of Engineering Sciences (SCI), Solid Mechanics (Dept.).
    Stemme, Göran
    KTH, School of Electrical Engineering (EES), Microsystem Technology.
    Penetration-enhanced ultrasharp microneedles and prediction on skin interaction for efficient transdermal drug delivery2007In: Journal of microelectromechanical systems, ISSN 1057-7157, E-ISSN 1941-0158, Vol. 16, no 6, p. 1429-1440Article in journal (Refereed)
    Abstract [en]

    This paper presents penetration-enhanced hollow microneedles and an analysis on the biomechanical interaction between microneedles and skin tissue. The aim of this paper is to fabricate microneedles that reliably penetrate the skin tissue without using penetration enhancers or special insertion tools that were used in the previous studies. The microneedles are made of silicon and feature ultrasharp tips and side openings. The microneedle chips were experimentally tested in vivo by injection of dye markers. To further investigate the penetration, the insertion progression and the insertion force were monitored by measuring the electrical impedance between microneedles and a counter electrode on the skin. The microneedle design was also tested using a novel simulation approach and compared to other previously published microneedle designs. The purpose of this specific part of the paper was to investigate the interaction mechanisms between a microneedle and the skin tissue. This investigation is used to predict how the skin deforms upon insertion and how microneedles can be used to create a leak-free liquid delivery into the skin. The fabricated microneedles successfully penetrated dry living human skin at all the tested sites. The insertion characteristic of the microneedle was superior to an earlier presented type, and the insertion force of a single microneedle was estimated to be below 10 mN. This low insertion force represents a significant improvement to earlier reported results and potentially allows a microneedle array with hundreds of needles to be inserted into tissue by hand.

  • 126672.
    Roxhed, Niclas
    et al.
    KTH, School of Electrical Engineering (EES), Microsystem Technology.
    Griss, Patrick
    KTH, School of Electrical Engineering (EES), Microsystem Technology.
    Stemme, Göran
    KTH, School of Electrical Engineering (EES), Microsystem Technology.
    A Method for Tapered Deep Reactive Ion Etching using a Modified Bosch Process2007In: Journal of Micromechanics and Microengineering, ISSN 0960-1317, E-ISSN 1361-6439, Vol. 17, no 5, p. 1087-1092Article in journal (Refereed)
    Abstract [en]

    This paper presents a method for etching tapered sidewalls in silicon using deep reactive ion etching. The method is based on consecutive switching between anisotropic etching using the Bosch process and isotropic dry etching. By controlling the etch depths of the anisotropic and isotropic etch sessions, the sidewall angle can be controlled over a relatively large range. Tapered sidewalls are useful in microfabrication processes such as metal coating of 3D structures (e. g. for electrical connections or vias), mold tool fabrication or as a tool to compensate for reentrant etching. The method was tested and characterized by etching basic test structures in silicon wafers. Based on the investigated anisotropic and isotropic etch depths the sidewall angle could be varied between 0 degrees (straight vertical) and 36 degrees. The sidewall angle was well predicted by a model using the etch depths as parameters. Due to the alternating etch procedure a scalloping pattern is generated on the sidewalls. By frequent switching and short etch sessions this scalloping can be reduced to less than 1 mu m. The process represents an easy method to tailor the sidewall angle in deep etching of silicon. The etch scheme is run in a single etch system and can be implemented in ICP systems of most manufactures. The method can also be used in conjunction with the standard Bosch process as demonstrated herein, where the method was applied to compensate for reentrant etching of high out-of-plane mesa-structures.

  • 126673.
    Roxhed, Niclas
    et al.
    KTH, School of Electrical Engineering (EES), Microsystem Technology.
    Griss, Patrick
    KTH, School of Electrical Engineering (EES), Microsystem Technology.
    Stemme, Göran
    KTH, School of Electrical Engineering (EES), Microsystem Technology.
    Generic leak-free drug storage and delivery for microneedle-based systems2005In: MEMS 2005 Miami: Technical Digest, 2005, p. 742-745Conference paper (Refereed)
    Abstract [en]

    We present a generic liquid packaging method for micromachined drug delivery systems with microneedles. Hollow microneedles are sealed with thin gold membranes at the openings on the needle tip on wafer level. This provides both a seal and an evaporation barrier to the drug delivery system on chip level. In addition, the membranes may also prevent drug delivery through needles that do not pierce the skin tissue. Applying a small voltage to the microneedle chip pressed onto the skin causes an electrochemical dissolving of membranes only at the needles that penetrated the skin tissue. The gold membrane sealed microneedles where tested for two types of operational modes. Opening the membranes by means of pressure showed that a minimum pressure of 125 kPa is needed to burst open the membranes. The removal of the gold membrane seal electrochemically was tested in vitro. The microneedle chip was opened within 2 min in the presence of an electrolyte comparable to the interstitial fluid.

  • 126674.
    Roxhed, Niclas
    et al.
    KTH, School of Electrical Engineering (EES), Microsystem Technology.
    Griss, Patrick
    Stemme, Göran
    KTH, School of Electrical Engineering (EES), Microsystem Technology.
    Membrane-sealed Hollow Microneedles and Related Administration Schemes for Transdermal Drug Delivery2008In: Biomedical microdevices (Print), ISSN 1387-2176, E-ISSN 1572-8781, Vol. 10, no 2, p. 271-279Article in journal (Refereed)
    Abstract [en]

    This paper presents fabrication and testing of membrane-sealed hollow microneedles. This novel concept offers the possibility of a sealed microneedle-based transdermal drug delivery system in which the drug is stored and protected from the environment. Sealed microneedles were fabricated by covering the tip openings of out-of-plane silicon microneedles with thin gold membranes. In this way a leak-tight seal was established which hinders both contamination and evaporation. To allow drug release from the microneedles, three different methods of opening the seals were investigated: burst opening by means of pressure; opening by applying a small voltage in the presence of physiological saline; and opening as a result of microneedle insertion into the skin. It was found that a 170 nm thick gold membrane can withstand a pressure of approximately 120 kPa. At higher pressures the membranes burst and the microneedles are opened up. The membranes can also be electrochemically dissolved within 2 min in saline conditions similar to interstitial fluid present in the skin. Moreover, through in vivo tests, it was demonstrated that 170 nm thick membranes break when the microneedles were inserted into skin tissue. The proposed concept was demonstrated as a feasible option for sealing hollow microneedles. This enables the realization of a closed-package transdermal drug delivery system based on microneedles.

  • 126675.
    Roxhed, Niclas
    et al.
    KTH, School of Electrical Engineering (EES), Microsystem Technology.
    Griss, Patrick
    KTH, School of Electrical Engineering (EES), Microsystem Technology.
    Stemme, Göran
    KTH, School of Electrical Engineering (EES), Microsystem Technology.
    Reliable in-vivo penetration and transdermal injection using ultra-sharp hollow microneedles2005In: Transducers '05, Digest of Technical Papers, Vols 1 and 2: Digest of Technical Papers, NEW YORK: IEEE , 2005, p. 213-216Conference paper (Other academic)
    Abstract [en]

    Minimally invasive microneedles is a promising technology for painless drug administration through the human skin. However, not all microneedle structures are capable to penetrate human skin in a repeatable and reliable fashion at moderate insertion forces. In this work we present an ultra-sharp hollow microneedle array, tailored for enhanced and reliable skin penetration capability. The microneedle apex has a tip radius below 100 nm. We show penetration and sustainable injection of liquid dye into dry living human skin without the use of any penetration enhancers. Microneedle liquid injection was also tested on clinically relevant sites, such as the shoulder and the upper arm. The electrical impedance was measured between the microneedle and a counter electrode showing continuous changes in the measured values during the insertion.

  • 126676.
    Roxhed, Niclas
    et al.
    KTH, School of Electrical Engineering (EES), Microsystem Technology.
    Griss, Patrick
    KTH, School of Electrical Engineering (EES), Microsystem Technology.
    Stemme, Göran
    KTH, School of Electrical Engineering (EES), Microsystem Technology.
    Tapered deep reactive ion etching: Method and characterization2007In: TRANSDUCERS '07 & EUROSENSORS XXI: DIGEST OF TECHNICAL PAPERS, NEW YORK: IEEE , 2007, p. 251-252Conference paper (Refereed)
    Abstract [en]

    This work presents a method for etching tapered sidewalls in silicon using deep reactive ion etching. The method is based on consecutive switching between anisotropic etching using the Bosch process and isotropic dry etching. By controlling the etch depths of the anisotropic and isotropic etch sessions, the sidewall angle can be controlled over a relatively large range, from 0 degrees (straight vertical) to 36 degrees. Tapered sidewalls are useful in microfabrication processes such as metal coating of 3D-structures (e.g. for electrical connections or vias), mold tool fabrication or as a tool to compensate for reentrant etching. The process represents an easy method to tailor the sidewall angle in deep etching of silicon. The etch scheme is run in a single etch system and can be implemented in ICP-systems of most manufactures. The method can also be used in conjunction with the standard Bosch process as demonstrated herein, where the method was applied to compensate for reentrant etching of high out-of-plane mesa-structures.

  • 126677.
    Roxhed, Niclas
    et al.
    KTH, School of Electrical Engineering (EES), Microsystem Technology.
    Niklaus, Frank
    KTH, School of Electrical Engineering (EES), Microsystem Technology.
    Adhesive Wafer Bonding and Applications2009In: Proceedings of Waferbond'09, 2009, p. 53-56Conference paper (Refereed)
    Abstract [en]

    Wafer bonding with intermediate polymer adhesives is an important fabrication technique that is beingused in manufacturing of various microelectronic, MEMS, photonic and microfluidic systems.Applications include heterogeneous integration, wafer-level packaging, three dimensional integratedcircuits (3D-ICs) and temporary handle wafer technologies. In adhesive wafer bonding, the polymeradhesive bears the forces involved to hold the surfaces together. The main advantages of adhesivewafer bonding include the insensitivity to surface topography, the low bonding temperatures, thecompatibility with standard integrated circuit wafer processing and the ability to join different types ofwafers. Compared to alternative wafer bonding techniques, adhesive wafer bonding is simple, robustand low cost. This paper reviews polymer adhesive wafer bonding technologies, its materials and itsapplications.

  • 126678.
    Roxhed, Niclas
    et al.
    KTH, School of Electrical Engineering (EES), Microsystem Technology.
    Niklaus, Frank
    KTH, School of Electrical Engineering (EES), Microsystem Technology.
    Fischer, Andreas
    KTH, School of Electrical Engineering (EES), Microsystem Technology.
    Forsberg, Fredrik
    KTH, School of Electrical Engineering (EES), Microsystem Technology.
    Höglund, Linda
    Ericsson, Per
    Acreo AB .
    Samel, Björn
    Acreo AB .
    Wissmar, Stanley
    Acreo AB .
    Elfving, Andreas
    Simonsen, Tor Ivar
    Wang, Kaiying
    Hoivik, Nils
    Low-cost uncooled microbolometers for thermal imaging2010In: OPTICAL SENSING AND DETECTION / [ed] Francis Berghmans, Anna G. Mignani, Chris A. van Hoof, 2010, Vol. 7726, p. 772611-Conference paper (Refereed)
    Abstract [en]

    Cost efficient integration technologies and materials for manufacturing of uncooled infrared bolometer focal plane arrays (FPA) are presented. The technology platform enables 320x240 pixel resolution with a pitch down to 20 mu m and very low NETD.

    A heterogeneous 3D MEMS integration technology called SOIC (Silicon-On-Integrated-Circuit) is used to combine high performance Si/SiGe bolometers with state-of-the-art electronic read-out-integrated-circuits.

    The SOIC integration process consists of: (a) Separate fabrication of the CMOS wafer and the MEMS wafer. (b) Adhesive wafer bonding. (c) Sacrificial removal of the MEMS handle wafer. (d) Via-hole etching. (e) Via formation and MEMS device definition. (f) Sacrificial etching of the polymer adhesive. We will present an optimized process flow that only contains dry etch processes for the critical process steps. Thus, extremely small, sub-micrometer feature sizes and vias can be implemented for the infrared bolometer arrays.

    The Si/SiGe thermistor is grown epitaxially, forming a mono-crystalline multi layer structure. The temperature coefficient of resistance (TCR) is primarily controlled by the concentration of Ge present in the strained SiGe layers. TCR values of more than 3%/K can be achieved with a low signal-to-noise ratio due to the mono-crystalline nature of the material. In addition to its excellent electrical properties, the thermistor material is thermally stable up to temperatures above 600 degrees C, thus enabling the novel integration and packaging techniques described in this paper.

    Vacuum sealing at the wafer level reduces the overall costs compared to encapsulation after die singulation. Wafer bonding is performed using a Cu-Sn based metallic bonding process followed by getter activation at >= 350 degrees C achieving a pressure in the 0.001 mbar range. After assembling, the final metal phases are stable and fully compatible with high-temperature processes. Hermeticity over the product lifetime is accomplished by well-controlled electro-deposition of metal layers, optimized bonding parameters and a suitable bond frame design.

  • 126679.
    Roxhed, Niclas
    et al.
    KTH, Superseded Departments (pre-2005), Signals, Sensors and Systems.
    Rydholm, Susanna
    KTH, Superseded Departments (pre-2005), Signals, Sensors and Systems.
    Samel, Björn
    KTH, Superseded Departments (pre-2005), Signals, Sensors and Systems.
    van der Wijngaart, Wouter
    KTH, Superseded Departments (pre-2005), Signals, Sensors and Systems.
    Griss, Patric
    KTH, Superseded Departments (pre-2005), Signals, Sensors and Systems.
    Stemme, Göran
    KTH, Superseded Departments (pre-2005), Signals, Sensors and Systems.
    LOW COST DEVICE FOR PRECISE MICROLITER RANGE LIQUID DISPENSIN2004In: 17th IEEE International Conference on Micro Electro Mechanical Systems (IEEE MEMS 2004), New York: IEEE conference proceedings, 2004, p. 326-329Conference paper (Refereed)
    Abstract [en]

    In this work we present the fabrication and testing of a thermally actuated one-shot liquid dispenser, which actuation is based on highly expandable microspheres. We show an uncomplicated, fully functional, low cost device for use in medical disposables, e.g. transdermal systems based on microneedles. All device components are made out of low cost materials and fabrication processes have the potential for high volume batch manufacturing. The device utilizes the properties of the expandable microspheres to form a heat insulating layer to the delivered liquid. Moreover, it does not require any feed-back or complicated flow metering. The device was successfully tested showing a mean dispensed liquid of 101 mul with a relative standard deviation of 3.2% and with a maximum temperature of 59 degreesC in the liquid during actuation. No back-flow was observed for the device.

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  • 126680.
    Roxhed, Niclas
    et al.
    KTH, School of Electrical Engineering (EES), Microsystem Technology.
    Rydholm, Susanna
    KTH, School of Electrical Engineering (EES), Microsystem Technology.
    Samel, Björn
    KTH, School of Electrical Engineering (EES), Microsystem Technology.
    van der Wijngaart, Wouter
    KTH, School of Electrical Engineering (EES), Microsystem Technology.
    Griss, Patrick
    KTH, School of Electrical Engineering (EES), Microsystem Technology.
    Stemme, Göran
    KTH, School of Electrical Engineering (EES), Microsystem Technology.
    A Compact, Low-cost Microliter-range Liquid Dispenser based on Expandable Microspheres2006In: Journal of Micromechanics and Microengineering, ISSN 0960-1317, E-ISSN 1361-6439, Vol. 16, no 12, p. 2740-2746Article in journal (Refereed)
    Abstract [en]

    This work presents a new low-cost liquid dispenser for the dispensing of microliters to milliliter volumes. The dispensing mechanism is based on a thermal actuator where highly expandable microspheres expand into a liquid reservoir consequently displacing any stored liquid. All device components are made out of low-cost materials and the fabrication process has the potential for high volume batch manufacturing. The device utilizes the property of the expandable microspheres to form a heat insulating layer between the heat source and the delivered liquid. Moreover, it does not require any feed back or complicated flow metering. The device was successfully tested showing a mean dispensed volume of 101 mu 1 with a standard deviation of 3.2% and with a maximum temperature of 59 degrees C in the liquid during actuation. It was shown that the dispenser is strong enough to deliver against counter pressures as high as 75 kPa. The device can also function as a low flow rate dispenser as demonstrated in a microfluidic dye laser application. The flow rate can be controlled between 1 mu 1 h(-1) and 2400 mu 1 h(-1) by adjusting the actuation power.

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  • 126681.
    Roxhed, Niclas
    et al.
    KTH, Superseded Departments (pre-2005), Signals, Sensors and Systems.
    Samel, Björn
    KTH, Superseded Departments (pre-2005), Signals, Sensors and Systems.
    Griss, Patrick
    KTH, Superseded Departments (pre-2005), Signals, Sensors and Systems.
    Stemme, Göran
    KTH, Superseded Departments (pre-2005), Signals, Sensors and Systems.
    Novel Technology Platforms with Expandable Microspheres2004In: Proceedings of the 5th Micro Structure Workshop, Ystad, March 30-31, 2004, 2004, p. 57-60Conference paper (Refereed)
  • 126682.
    Roxhed, Niclas
    et al.
    KTH, School of Electrical Engineering (EES), Microsystem Technology.
    Samel, Björn
    KTH, School of Electrical Engineering (EES), Microsystem Technology.
    Nordquist, L.
    Dept of Medical Cell Biology, Uppsala University.
    Griss, Patrick
    KTH, School of Electrical Engineering (EES), Microsystem Technology.
    Stemme, Göran
    KTH, School of Electrical Engineering (EES), Microsystem Technology.
    Compact seamless integration of active dosing and actuation with microneedles for transdermal drug delivery2006In: MEMS 2006: 19th IEEE International Conference on Micro Electro Mechanical Systems, Technical Digest , New York: IEEE , 2006, p. 414-417Conference paper (Refereed)
    Abstract [en]

    This paper presents the seamless integration of a dosing and actuation unit capable of controlled release of liquid in the microliter range at very low flow-rates (mu l/h) with painless, hollow microneedles for transdermal liquid delivery. This novel system was tested in-vivo on human and rat skin and allows the detailed study of liquid uptake in biological tissue. Experiments with infusion of radioactive marker into rat shows that the actively infused liquid was successfully delivered trough the skin layer and absorbed by the circulatory system. It was also noted that, for the given way of device attachment, the amount of liquid that can be absorbed by the skin tissue is limited to a few mu l/h. The presented device represents the first step towards a transdermal patch allowing for applications where very precise amounts of liquid need to be delivered into the skin (e.g. insulin). The novelty of this work is the significant step from non-integrated modules earlier presented by our and other groups into a complete microsystem.

  • 126683.
    Roxhed, Niclas
    et al.
    KTH, School of Electrical Engineering (EES), Microsystem Technology.
    Samel, Björn
    KTH, School of Electrical Engineering (EES), Microsystem Technology.
    Nordquist, Lina
    Department of Medical Cell Biology, Division of Integrative Physiology, Uppsala University.
    Griss, Patrick
    Zühlke Engineering AG, Zurich.
    Stemme, Göran
    KTH, School of Electrical Engineering (EES), Microsystem Technology.
    Painless Drug Delivery through Microneedle-based Transdermal Patches featuring Active Infusion2008In: IEEE Transactions on Biomedical Engineering, ISSN 0018-9294, E-ISSN 1558-2531, Vol. 55, no 3, p. 1063-1071Article in journal (Refereed)
    Abstract [en]

    This paper presents the first microneedle-based transdermal patch with integrated active dispensing functionality. The electrically controlled system consists of a low-cost dosing and actuation unit capable of controlled release of liquid in the microliter range at low flow-rates and minimally invasive, side-opened, microneedles. The system was successfully tested in vivo by insulin administration to diabetic rats. Active infusion of insulin at 2 mu l/h was compared to passive, diffusion-driven, delivery. Continuous active infusion caused significantly higher insulin concentrations in blood plasma. After a 3-h delivery period, the insulin concentration was five times larger compared to passive delivery. Consistent with insulin concentrations, actively administered insulin resulted in a significant decrease of blood glucose levels. Additionally, insertion and liquid injection was verified on human skin. This study shows the feasibility of a patch-like system with on-board liquid storage and dispensing capability. The proposed device represents a first step towards painless and convenient administration of macromolecular drugs such as insulin or vaccines.

  • 126684. Roxstrom-Lindquist, K.
    et al.
    Assefaw-Redda, Yohannes
    Rosinska, K.
    Faye, I.
    20-Hydroxyecdysone indirectly regulates Hemolin gene expression in Hyalophora cecropia2005In: Insect molecular biology (Print), ISSN 0962-1075, E-ISSN 1365-2583, Vol. 14, no 6, p. 645-652Article in journal (Refereed)
    Abstract [en]

    Development and innate immune defence are two vital processes that have been demonstrated to use the same or similar molecules and signalling pathways in insects. Hemolin is a moth haemolymph protein belonging to the immunoglobulin superfamily. It is strongly induced upon bacterial infection. However, recent studies indicate a developmental regulation of hemolin. We show that the steroid hormone 20-hydroxyecdysone (20E) can activate the expression of Hyalophora cecropia Hemolin (HcHemolin) in the fat body of diapausing pupae. Using the protein synthesis inhibitor cycloheximide we demonstrate that Hemolin up-regulation by 20E requires ongoing protein synthesis. Moreover, 20E enhances transcription of the Hemolin gene in response to bacteria. Comparing the upstream regions of Manduca sexta Hemolin (MsHemolin) and HcHemolin, we identified four putative regulatory sites. Two are putative hormone response elements (HREs), one with an imperfect inverted repeat (HRE-IR) and one with a monomeric site (HRE-M). An additional monomeric hormone receptor site (MRE) is present only in HcHemolin. The third conserved motif is similar to the interferon (IFN) regulatory factor binding element (IRF-E) and IFN-stimulated response element (ISRE). The fourth conserved element is a kappa B motif situated between the Cap-site and the TATA-box. Finally, by electrophoresis mobility shift assay we demonstrate that the HRE-IR forms specific complexes with nuclear extract proteins of normal pupae that increase after 20E stimulation.

  • 126685.
    Roy, Arijit Sinha
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Fridh, Jens
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Scobie, James
    University of Bath, Claverton Down, Bath BA2 7AY, UK.
    Sangan, Carl
    University of Bath, Claverton Down, Bath BA2 7AY, UK.
    Lock, Gary
    University of Bath, Claverton Down, Bath BA2 7AY, UK.
    Flow instability effects related to purge through a gas turbine chute seal2021In: Journal of the Global Power and Propulsion Society, E-ISSN 2515-3080, Vol. 5, p. 111-125Article in journal (Refereed)
    Abstract [en]

    This paper investigates flow instabilities inside the cavity formed between the stator and rotor disks of a high-speed turbine rig. The cavity rim seal is of chute seal design. The influence of flow coefficient on the sealing effectiveness at constant purge flow rate through the wheel-space is determined. The effectiveness at different radial positions over a range of purge flow conditions and flow coefficients is also studied. Unsteady pressure measurements have identified the frequency of instabilities that form within the rim seal, phenomena which have been observed in other studies. Frequencies of these disturbances, and their correlation in the circumferential direction have determined the strength and speed of rotation of the instabilities within the cavity. Large scale unsteady rotational structures have been identified, which show similarity to previous studies. These disturbances have been found to be weakly dependent on the purge flow and flow coefficients, although an increased purge reduced both the intensity and speed of rotation of the instabilities. Additionally, certain uncorrelated disturbances have been found to be inconsistent (discontinuous) with pitchwise variation.

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  • 126686.
    Roy, Axel
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Environmental Strategies.
    From a complex to a simpler building product Life-Cycle Assessment (LCA): Focus on simplification of LCA conduct for electronic and electrical equipment2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
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    From a complex to a simpler building product Life-Cycle Assessment (LCA): Focus on simplification of LCA conduct for electronic and electrical equipment
  • 126687. Roy, B.
    et al.
    Goswami, P.
    Juričić, Vladimir
    KTH, Centres, Nordic Institute for Theoretical Physics NORDITA.
    Interacting Weyl fermions: Phases, phase transitions, and global phase diagram2017In: Physical Review B, ISSN 2469-9950, E-ISSN 2469-9969, Vol. 95, no 20, article id 201102Article in journal (Refereed)
    Abstract [en]

    We study the effects of short-range interactions on a generalized three-dimensional Weyl semimetal, where the band touching points act as the (anti)monopoles of Abelian Berry curvature of strength n. We show that any local interaction has a negative scaling dimension -2/n. Consequently, all Weyl semimetals are stable against weak short-range interactions. For sufficiently strong interactions, we demonstrate that the Weyl semimetal either undergoes a first-order transition into a band insulator or a continuous transition into a symmetry breaking phase. A translational symmetry breaking axion insulator and a rotational symmetry breaking semimetal are two prominent candidates for the broken symmetry phase. At the one-loop order, the correlation length exponent for continuous transitions is ν=n/2, indicating their non-Gaussian nature for any n>1. We also discuss the scaling of the thermodynamic and transport quantities in general Weyl semimetals as well as inside broken symmetry phases.

  • 126688. Roy, B.
    et al.
    Goswami, P.
    Juričić, Vladimir
    KTH, Centres, Nordic Institute for Theoretical Physics NORDITA. Stockholm Univ, Roslagstullsbacken 23, S-10691 Stockholm, Sweden.
    Itinerant quantum multicriticality of two-dimensional Dirac fermions2018In: Physical Review B, ISSN 2469-9950, E-ISSN 2469-9969, Vol. 97, no 20, article id 205117Article in journal (Refereed)
    Abstract [en]

    We analyze emergent quantum multicriticality for strongly interacting, massless Dirac fermions in two spatial dimensions (d=2) within the framework of Gross-Neveu-Yukawa models, by considering the competing order parameters that give rise to fully gapped (insulating or superconducting) ground states. We focus only on those competing orders which can be rotated into each other by generators of an exact or emergent chiral symmetry of massless Dirac fermions, and break O(S1) and O(S2) symmetries in the ordered phase. Performing a renormalization-group analysis by using the ϵ=(3-d) expansion scheme, we show that all the coupling constants in the critical hyperplane flow toward a new attractive fixed point, supporting an enlarged O(S1+S2) chiral symmetry. Such a fixed point acts as an exotic quantum multicritical point (MCP), governing the continuous semimetal-insulator as well as insulator-insulator (for example, antiferromagnet to valence bond solid) quantum phase transitions. In comparison with the lower symmetric semimetal-insulator quantum critical points, possessing either O(S1) or O(S2) chiral symmetry, the MCP displays enhanced correlation length exponents, and anomalous scaling dimensions for both fermionic and bosonic fields. We discuss the scaling properties of the ratio of bosonic and fermionic masses, and the increased dc resistivity at the MCP. By computing the scaling dimensions of different local fermion bilinears in the particle-hole channel, we establish that most of the four fermion operators or generalized density-density correlation functions display faster power-law decays at the MCP compared to the free fermion and lower symmetric itinerant quantum critical points. Possible generalization of this scenario to higher-dimensional Dirac fermions is also outlined.

  • 126689. Roy, B.
    et al.
    Juricic, Vladimir
    KTH, Centres, Nordic Institute for Theoretical Physics NORDITA.
    Das Sarma, Sankar
    Universal optical conductivity of a disordered Weyl semimetal2016In: Scientific Reports, E-ISSN 2045-2322, Vol. 6, article id 32446Article in journal (Refereed)
    Abstract [en]

    Topological Weyl semimetals, besides manifesting chiral anomaly, can also accommodate a disorder-driven unconventional quantum phase transition into a metallic phase. A fundamentally and practically important question in this regard concerns an experimentally measurable quantity that can clearly distinguish these two phases. We show that the optical conductivity while serving this purpose can also play the role of a bonafide order parameter across such disorder-driven semimetal-metal quantum phase transition by virtue of displaying distinct scaling behavior in the semimetallic and metallic phases, as well as inside the quantum critical fan supporting a non-Fermi liquid. We demonstrate that the correction to the dielectric constant and optical conductivity in a dirty Weyl semimetal due to weak disorder is independent of the actual nature of point-like impurity scatterers. Therefore, optical conductivity can be used as an experimentally measurable quantity to study the critical properties and to pin the universality class of the disorder-driven quantum phase transition in Weyl semimetals.

  • 126690. Roy, B.
    et al.
    Juričić, Vladimir
    KTH, Centres, Nordic Institute for Theoretical Physics NORDITA. Stockholm University, Roslagstullsbacken 23, Stockholm, 10691, Sweden.
    Fermionic multicriticality near Kekulé valence-bond ordering on a honeycomb lattice2019In: Physical Review B, ISSN 2469-9950, E-ISSN 2469-9969, Vol. 99, no 24, article id 241103Article in journal (Refereed)
    Abstract [en]

    We analyze the possibility of emergent quantum multicritical points (MCPs) with enlarged chiral symmetry, when strongly interacting gapless Dirac fermions acquire a comparable propensity toward the nucleation of Kekulé valence-bond solid (KVBS) and charge-density-wave (Nb=1) or s-wave pairing (Nb=2) or antiferromagnet (Nb=3) in a honeycomb lattice, where Nb counts the number of bosonic order-parameter components. Besides the cubic terms present in the order-parameter description of KVBS due to the breaking of a discrete Z3 symmetry, quantum fluctuations generate new cubic vertices near the high-symmetry MCPs. All cubic terms are strongly relevant at the bare level near three spatial dimensions, about which we perform a leading-order renormalization group analysis of coupled Gross-Neveu-Yukawa field theory. We show that due to nontrivial Yukawa interactions among gapless bosonic and fermionic degrees of freedom, all cubic terms ultimately become irrelevant at an O(2+Nb) symmetric MCP, at leas near two spatial dimensions, where Nb=1,2,3. Therefore, MCPs with an enlarged O(2+Nb) symmetry near KVBS ordering are stable.

  • 126691. Roy, B.
    et al.
    Juričić, Vladimir
    KTH, Centres, Nordic Institute for Theoretical Physics NORDITA. Utrecht University, Netherlands .
    Herbut, I. F.
    Emergent Lorentz symmetry near fermionic quantum critical points in two and three dimensions2016In: Journal of High Energy Physics (JHEP), ISSN 1126-6708, E-ISSN 1029-8479, Vol. 2016, no 4, article id 018Article in journal (Refereed)
    Abstract [en]

    We study the renormalization group flow of the velocities in the field theory describing the coupling of the massless quasi-relativistic fermions to the bosons through the Yukawa coupling, as well as with both bosons and fermions coupled to a fluctuating U(1) gauge field in two and three spatial dimensions. Different versions of this theory describe quantum critical behavior of interacting Dirac fermions in various condensed-matter systems. We perform an analysis using one-loop ϵ-expansion about three spatial dimensions, which is the upper critical dimension in the problem. In two dimensions, we find that velocities of both charged fermions and bosons ultimately flow to the velocity of light, independently of the initial conditions, the number of fermionic and bosonic flavors, and the value of the couplings at the critical point. In three dimensions, due to the analyticity of the gauge field propagator, both the U(1) charge and the velocity of light flow, which leads to a richer behavior than in two dimensions. We show that all three velocities ultimately flow to a common terminal velocity, which is non-universal and different from the original velocity of light. Therefore, emergence of the Lorentz symmetry in the ultimate infrared regime seems to be a rather universal feature of this class of theories in both two and three dimensions.

  • 126692. Roy, B.
    et al.
    Kennett, M. P.
    Yang, K.
    Juricic, Vladimir
    KTH, Centres, Nordic Institute for Theoretical Physics NORDITA.
    From Birefringent Electrons to a Marginal or Non-Fermi Liquid of Relativistic Spin- 1/2 Fermions: An Emergent Superuniversality2018In: Physical Review Letters, ISSN 0031-9007, E-ISSN 1079-7114, Vol. 121, no 15, article id 157602Article in journal (Refereed)
    Abstract [en]

    We present the quantum critical theory of an interacting nodal Fermi liquid of quasirelativistic pseudospin-3/2 fermions that have a noninteracting birefringent spectrum with two distinct Fermi velocities. When such quasiparticles interact with gapless bosonic degrees of freedom that mediate either the long-range Coulomb interaction or its short range component (responsible for spontaneous symmetry breaking), in the deep infrared or quantum critical regime in two dimensions, the system is, respectively, described by a marginal- or a non-Fermi liquid of relativistic spin-1/2 fermions (possessing a unique velocity), and is always a marginal Fermi liquid in three dimensions. We consider a possible generalization of these scenarios to fermions with an arbitrary half-odd-integer spin, and conjecture that critical spin-1/2 excitations represent a superuniversal description of the entire family of interacting quasirelativistic fermions.

  • 126693.
    Roy, Bitan
    et al.
    Max Planck Inst Phys Komplexer Syst, Nothnitzer Str 38, D-01187 Dresden, Germany..
    Juricic, Vladimir
    KTH, Centres, Nordic Institute for Theoretical Physics NORDITA.
    Collisionless Transport Close to a Fermionic Quantum Critical Point in Dirac Materials2018In: Physical Review Letters, ISSN 0031-9007, E-ISSN 1079-7114, Vol. 121, no 13, article id 137601Article in journal (Refereed)
    Abstract [en]

    Quantum transport close to a critical point is a fundamental, but enigmatic problem due to fluctuations, persisting at all length scales. We report the scaling of optical conductivity (OC) in the collisionless regime ((sic)omega >> k(B)T) in the vicinity of a relativistic quantum critical point, separating two-dimensional (d = 2) massless Dirac fermions from a fully gapped insulator or superconductor. Close to such a critical point, gapless fermionic and bosonic excitations are strongly coupled, leading to a universal suppression of the interband OC as well as of the Drude peak (while maintaining its delta function profile) inside the critical regime, which we compute to the leading order in 1/N-f- and epsilon expansions, where N-f counts the fermion flavor number and epsilon = 3 - d. Correction to the OC at such a non-Gaussian critical point due to the longrange Coulomb interaction and generalizations of these scenarios to a strongly interacting three-dimensional Dirac or Weyl liquid are also presented, which can be tested numerically and possibly from nonperturbative gauge-gravity duality, for example.

  • 126694.
    Roy, Bitan
    et al.
    Lehigh Univ, Dept Phys, Bethlehem, PA 18015 USA..
    Juricic, Vladimir
    KTH, Centres, Nordic Institute for Theoretical Physics NORDITA.
    Dislocation as a bulk probe of higher-order topological insulators2021In: Physical Review Research, E-ISSN 2643-1564, Vol. 3, no 3, article id 033107Article in journal (Refereed)
    Abstract [en]

    Topological materials occupy the central stage in the modern condensed matter physics because of their robust metallic edge or surface states protected by the topological invariant, characterizing the electronic band structure in the bulk. Higher-order topological (HOT) states extend this usual bulk-boundary correspondence, so they host the modes localized at lower-dimensional boundaries, such as corners and hinges. Here we theoretically demonstrate that dislocations, ubiquitous defects in crystalline materials, can probe higher-order topology, recently realized in various platforms. We uncover that HOT insulators respond to dislocations through symmetry protected finite-energy in-gap electronic modes, localized at the defect core, which originate from an interplay between the orientation of the HOT mass domain wall and the Burgers vector of the dislocation. As such, these modes become gapless only when the Burgers vector points toward lower-dimensional gapless boundaries. Our findings are consequential for the systematic probing of the extended bulk-boundary correspondence in a broad range of HOT crystals and photonic and phononic or mechanical metamaterials through the bulk topological lattice defects.

  • 126695.
    Roy, Bitan
    et al.
    Lehigh Univ, Dept Phys, Bldg 16, Bethlehem, PA 18015 USA..
    Juricic, Vladimir
    KTH, Centres, Nordic Institute for Theoretical Physics NORDITA. Univ Tecn Federico Santa Maria, Dept Fis, Casilla 110, Valparaiso, Chile..
    Mixed-parity octupolar pairing and corner Majorana modes in three dimensions2021In: Physical Review B, ISSN 2469-9950, E-ISSN 2469-9969, Vol. 104, no 18, article id L180503Article in journal (Refereed)
    Abstract [en]

    We identify time-reversal symmetry breaking mixed-parity superconducting states that feature eight Majorana corner modes in properly cleaved three-dimensional cubic crystals. Namely, when an odd-parity isotropic p-wave pairing coexists with cubic symmetry preserving even-parity octupolar d(x2-y2) + id(3z2-r2) pairing, the gapless surface Majorana modes of the former get localized at the eight corners, thus yielding an intrinsic third-order topological superconductor (TOTSC). A cousin d(xy) + id(3z2-r2) pairing also accommodating eight corner Majorana modes, by virtue of breaking the cubic symmetry, in contrast, yields an extrinsic TOTSC. We identify a doped octupolar (topological or trivial) Dirac insulator as a suitable platform to sustain such unconventional superconductors, realized from an intraunit cell pairing. Finally, we argue that the proposed TOTSC can be experimentally realizable in NaCl and other structurally similar compounds under high pressure.

  • 126696. Roy, Bitan
    et al.
    Juricic, Vladimir
    KTH, Centres, Nordic Institute for Theoretical Physics NORDITA.
    Optical conductivity of an interacting Weyl liquid in the collisionless regime2017In: Physical Review B, ISSN 2469-9950, E-ISSN 2469-9969, Vol. 96, no 15, article id 155117Article in journal (Refereed)
    Abstract [en]

    Optical conductivity (OC) can serve as a measure of correlation effects in a wide range of condensed-matter systems. We show that the long-range tail of the Coulomb interaction yields a universal correction to the OC in a three-dimensional Weyl semimetal sigma(Omega) = sigma(0)(Omega)[1 + 1/N+1], where sigma(0)(Omega) = Ne-0(2)Omega/(12hv) is the OC in the noninteracting system, with v as the actual (renormalized) Fermi velocity of Weyl quasiparticles at frequency Omega, and e(0) is the electron charge in vacuum. Such universal enhancement of OC, which depends only on the number of Weyl nodes near the Fermi level (N), is a remarkable consequence of an intriguing conspiracy among the quantum-critical nature of an interacting Weyl liquid, marginal irrelevance of the long-range Coulomb interaction, and violation of hyperscaling in three dimensions, and can directly be measured in recently discovered Weyl as well as Dirac materials. By contrast, a local density-density interaction produces a nonuniversal correction to the OC, stemming from the nonrenormalizable nature of the corresponding interacting field theory.

  • 126697.
    Roy, Bitan
    et al.
    Lehigh Univ, Dept Phys, Bldg 16, Bethlehem, PA 18015 USA..
    Juricic, Vladimir
    KTH, Centres, Nordic Institute for Theoretical Physics NORDITA. Stockholm Univ, Roslagstullsbacken 23, S-10691 Stockholm, Sweden..
    Relativistic non-Fermi liquid from interacting birefringent fermions: A robust superuniversality2020In: Physical Review Research, E-ISSN 2643-1564, Vol. 2, no 1, article id 012047Article in journal (Refereed)
    Abstract [en]

    We address the emergent quantum critical phenomena for (pseudo)spin-3/2 birefringent fermions, featuring two effective Fermi velocities, when they reside close to itinerant Mott transitions realized through spontaneous symmetry breaking and triggered by strong local or Hubbard-like repulsive interactions. Irrespective of the nature of the mass orderings that produce fully gapped quasiparticle spectra in the ordered phase, which otherwise can be grouped into three classes, the system always possesses a unique terminal velocity near the corresponding quantum critical point. The associated critical regime accommodates a relativistic non-Fermi liquid of strongly coupled collective bosonic and spin-1/2 Dirac excitations with vanishing weight of the quasiparticle pole. These conclusions are also operative near superconducting critical points. Therefore, relativistic non-Fermi liquid possibly constitutes a robust superuniversal description for the entire family of strongly correlated arbitrary half-integer spin Dirac materials.

  • 126698.
    Roy, Bitan
    et al.
    Max Planck Inst Phys Komplexer Syst, Nothnitzer Str 38, D-01187 Dresden, Germany. .
    Juricic, Vladimir
    KTH, Centres, Nordic Institute for Theoretical Physics NORDITA. Stockholm Univ, Roslagstullsbacken 23, S-10691 Stockholm, Sweden.
    Unconventional superconductivity in nearly flat bands in twisted bilayer aphene2019In: Physical Review B, ISSN 2469-9950, E-ISSN 2469-9969, Vol. 99, no 12, article id 121407Article in journal (Refereed)
    Abstract [en]

    Flat electronic bands can accommodate a plethora of interaction-driven quantum phases, since kinetic energy is quenched therein and electronic interactions therefore prevail. Twisted bilayer graphene, near the so-called "magic angles", features slow Dirac fermions close to the charge-neutrality point that persist up to high energies. Starting from a continuum model of slow but strongly interacting Dirac fermions, we show that with increasing chemical doping away from the charge-neutrality point, a time-reversal symmetry breaking, valley pseudospin-triplet, topological p + ip superconductor gradually sets in, when the system resides at the brink of an antiferromagnetic ordering (due to Hubbard repulsion), in qualitative agreement with recent experimental findings. The p ip paired state exhibits quantized spin and thermal Hall conductivities, and polar Kerr and Faraday rotations. Our conclusions should also be applicable for other correlated two-dimensional Dirac materials.

  • 126699.
    Roy, Bitan
    et al.
    Department of Physics, Lehigh University, Bethlehem, Pennsylvania 18015, USA.
    Juričić, Vladimir
    KTH, Centres, Nordic Institute for Theoretical Physics NORDITA. Departamento de Física, Universidad Técnica Federico Santa María, Casilla 110, Valparaíso, Chile, Casilla 110.
    Correlated fractional Dirac materials2023In: Physical Review Research, E-ISSN 2643-1564, Vol. 5, no 3, article id L032002Article in journal (Refereed)
    Abstract [en]

    Fractional Dirac materials (FDMs) feature a fractional energy-momentum relation E(k)∼|k|α, where α(<1) is a real noninteger number, in contrast to that in conventional Dirac materials with α=1. Here we analyze the effects of short- and long-range Coulomb repulsions in two- and three-dimensional FDMs. Only a strong short-range interaction causes nucleation of a correlated insulator that takes place through a quantum critical point. The universality class of the associated quantum phase transition is determined by the correlation length exponent ν-1=d-α and dynamic scaling exponent z=α, set by the band curvature. On the other hand, the fractional dispersion is protected against long-range interaction due to its nonanalytic structure. Rather, a linear Dirac dispersion gets generated under coarse graining, and the associated Fermi velocity increases logarithmically in the infrared regime, thereby yielding a two-fluid system. Altogether, correlated FDMs unfold a rich landscape accommodating unconventional emergent many-body phenomena.

  • 126700.
    Roy, Bitan
    et al.
    Univ Maryland, Condensed Matter Theory Ctr, College Pk, MD 20742 USA.;Univ Maryland, Joint Quantum Inst, College Pk, MD 20742 USA.;Rice Univ, Dept Phys & Astron, Houston, TX 77005 USA.;Max Planck Inst Phys Komplexer Syst, Nothnitzer Str 38, D-01187 Dresden, Germany..
    Slager, Robert-Jan
    Max Planck Inst Phys Komplexer Syst, Nothnitzer Str 38, D-01187 Dresden, Germany..
    Juricic, Vladimir
    KTH, Centres, Nordic Institute for Theoretical Physics NORDITA.
    Global Phase Diagram of a Dirty Weyl Liquid and Emergent Superuniversality2018In: Physical Review X, E-ISSN 2160-3308, Vol. 8, no 3, article id 031076Article in journal (Refereed)
    Abstract [en]

    Pursuing complementary field-theoretic and numerical methods, we here paint the global phase diagram of a three-dimensional dirty Weyl system. The generalized Harris criterion, augmented by a perturbative renormalization-group analysis shows that weak disorder is an irrelevant perturbation at the Weyl semimetal (WSM)-insulator quantum-critical point. But, a metallic phase sets in through a quantum phase transition (QPT) at strong disorder across a multicritical point. The field-theoretic predictions for the correlation length exponent v = 2 and dynamic scaling exponent z = 5/4 at this multicritical point are in good agreement with the ones extracted numerically, yielding v = 1.98 +/- 0.10 and z = 1.26 +/- 0.05, from the scaling of the average density of states (DOS). Deep inside the WSM phase, generic disorder is also an irrelevant perturbation, while a metallic phase appears at strong disorder through a QPT. We here demonstrate that in the presence of generic but strong disorder, the WSM-metal QPT is ultimately always characterized by the exponents v = 1 and z = 3/2 (to one-loop order), originating from intranode or chiral-symmetric (e.g., regular and axial potential) disorder. We here anchor such emergent chiral super-universality through complementary renormalization-group calculations, controlled via. expansions, and numerical analysis of average DOS across WSM-metal QPT. In addition, we also discuss a subsequent QPT (at even stronger disorder) of a Weyl metal into an Anderson insulator by numerically computing the typical DOS at zero energy. The scaling behavior of various physical observables, such as residue of quasiparticle pole, dynamic conductivity, specific heat, Gruneisen ratio, inside various phases as well as across various QPTs in the global phase diagram of a dirty Weyl liquid, are discussed.

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