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991.
Szeftel Jacob Sandeau Nicolas Ghantous Michel Abou 《Journal of Superconductivity and Novel Magnetism》2022,35(1):65-72
Journal of Superconductivity and Novel Magnetism - A new picture of the Josephson effect is devised. The radio-frequency (RF) signal, observed in a Josephson junction, is shown to stem from bound... 相似文献
992.
Dominik Gall Riko Jacob Andrea Richa Christian Scheideler Stefan Schmid Hanjo Täubig 《Theory of Computing Systems》2014,55(1):110-135
Topological self-stabilization is an important concept to build robust open distributed systems (such as peer-to-peer systems) where nodes can organize themselves into meaningful network topologies. The goal is to devise distributed algorithms where nodes forward, insert, and delete links to neighboring nodes, and that converge quickly to such a desirable topology, independently of the initial network configuration. This article proposes a new model to study the parallel convergence time. Our model sheds light on the achievable parallelism by avoiding bottlenecks of existing models that can yield a distorted picture. As a case study, we consider local graph linearization—i.e., how to build a sorted list of the nodes of a connected graph in a distributed and self-stabilizing manner. In order to study the main structure and properties of our model, we propose two variants of a most simple local linearization algorithm. For each of these variants, we present analyses of the worst-case and best-case parallel time complexities, as well as the performance under a greedy selection of the actions to be executed. It turns out that the analysis is non-trivial despite the simple setting, and to complement our formal insights we report on our experiments which indicate that the runtimes may be better in the average case. 相似文献
993.
Kent Jacob Nielsen 《Construction Management & Economics》2017,35(3):154-169
Denmark has a 39% higher rate of fatal occupational injuries within construction than Sweden. Although there are only minor differences in the work environment legislation between the countries, there may be differences in how the legislation is enforced. The aim of the study was to describe and compare the inspection practices, within the construction industry, between the Danish and Swedish Work Environment Authorities. A mixed-method approach was employed combining observations of inspections, interviews with inspectors and questionnaire responses from inspected workplaces. The primary role of both Danish and Swedish inspectors was as controllers. A minor role was as experts. A third role of being a sounding board was only identified in a few instances in Sweden. Autonomy-supportive tactics were employed more regularly in Sweden while coercive tactics were more widespread in Denmark. Negative behaviour on behalf of the inspected party was also more widespread in Denmark while positive behaviour was more widespread in Sweden. Questionnaire data revealed that the inspected Swedish companies had a significantly more positive perception of the inspectors and the benefits of the inspections. There were differences in the enforcement practices of the Danish and Swedish inspectors, which may lead to greater adherence to health and safety regulations in Sweden. 相似文献
994.
Development of new hybrid ultrafiltration membranes by entanglement of macromolecular PPSU‐SO3H chains: Preparation,morphologies, mechanical strength,and fouling resistant properties 下载免费PDF全文
The present work focuses on the preparation of Polyphenylsulfone (PPSU) membranes with enhanced antifouling surfaces through an incorporation of sulfonated Polyphenylsulfone (PPSU‐SO3H), which acts as both, surface modifying agent and macromolecular additive. Initially, Sulfonated polyphenylsulfone (PPSU‐SO3H) was synthesized by using chlosulfonic acid via bulk modification method. The degree of sulfonation (DS, %) of PPSU‐SO3H was calculated by using NMR (nuclear magnetic resonance).The phase inversion technique was used to prepare all asymmetric membranes by allowing the PPSU‐SO3H (different wt %) to entangle with the PPSU membrane matrix. All prepared membranes were characterized by using scanning electron microscope (SEM), X‐ray diffraction analysis (XRD), contact angle analysis (CA), mechanical strength analysis, molecular weight cut off (MWCO), porosity (%), mean pore size, and BSA adsorption studies. The performance efficiency of the membranes was evaluated by using BSA protein as a model foulant in terms of permeability, rejection (SR %), Rm (hydraulic resistance), Rc (cake layer resistance), Rp (pore plugging resistance), Rr (reversible fouling), Rir (irreversible fouling), and FRR (flux recovery ratio). © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41986. 相似文献
995.
Buildings use approximately 40% of primary energy with most energy expended on the provision of a comfortable indoor climate. An extended range of indoor temperatures can significantly reduce the energy load. However, lower temperature set points for heating can cause thermal discomfort. Giving building occupants the option to warm themselves (e.g. a local source at their desk or workstation) can mitigate this discomfort by the provision of a personalized conditioning system. A model is presented to assess the performance of personalized heating and its impact on the whole building energy load. Researchers, designers and facility managers can use this model to compare performance and analyse energy savings. The total energy use of personalized heating is estimated by scaling its settings to the actual level of discomfort resulting from a lowered heating set point. This model is used to assess seven different personalized heating systems. Assessments reveal that personalized heating brings a remarkable energy-saving potential, while maintaining or even improving individually perceived thermal comfort. Assessments are based on an assumed linear relation between the power and level of increased thermal sensation. Future research in personalized conditioning systems should be directed towards the development of the full characteristics and specific settings. 相似文献
996.
Evaluating Ketoreductase Exchanges as a Means of Rationally Altering Polyketide Stereochemistry 下载免费PDF全文
Thibault Annaval Cédric Paris Prof. Peter F. Leadlay Dr. Christophe Jacob Prof. Kira J. Weissman 《Chembiochem : a European journal of chemical biology》2015,16(9):1357-1364
Modular polyketide synthases (PKSs) are multidomain multienzymes responsible for the biosynthesis in bacteria of a wide range of polyketide secondary metabolites of clinical value. The stereochemistry of these molecules is an attractive target for genetic engineering in attempts to produce analogues exhibiting novel therapeutic properties. The exchange of ketoreductase (KR) domains in model PKSs has been shown in several cases to predictably alter the configuration of the β‐hydroxy functionalities but not of the α‐methyl groups. By systematic screening of a broad panel of KR domains, we have identified two donor KRs that afford modification of α‐methyl group stereochemistry. To the best of our knowledge, this provides the first direct in vivo evidence of KR‐catalyzed epimerization. However, none of the introduced KRs afforded simultaneous alteration of methyl and hydroxy configurations in high yield. Therefore, swapping of whole modules might be necessary to achieve such changes in stereochemistry. 相似文献
997.
Ultramild Protein‐Mediated Click Chemistry Creates Efficient Oligonucleotide Probes for Targeting and Detecting Nucleic Acids 下载免费PDF全文
Lina J. Nåbo Dr. Charlotte S. Madsen Prof. Dr. Knud J. Jensen Prof. Dr. Jacob Kongsted Prof. Dr. Kira Astakhova 《Chembiochem : a European journal of chemical biology》2015,16(8):1163-1167
Functionalized synthetic oligonucleotides are finding growing applications in research, clinical studies, and therapy. However, it is not easy to prepare them in a biocompatible and highly efficient manner. We report a new strategy to synthesize oligonucleotides with promising nucleic acid targeting and detection properties. We focus in particular on the pH sensitivity of these new probes and their high target specificity. For the first time, human copper(I)‐binding chaperon Cox17 was applied to effectively catalyze click labeling of oligonucleotides. This was performed under ultramild conditions with fluorophore, peptide, and carbohydrate azide derivatives. In thermal denaturation studies, the modified probes showed specific binding to complementary DNA and RNA targets. Finally, we demonstrated the pH sensitivity of the new rhodamine‐based fluorescent probes in vitro and rationalize our results by electronic structure calculations. 相似文献
998.
The Use of Nanoparticles to Deliver Nitric Oxide to Hepatic Stellate Cells for Treating Liver Fibrosis and Portal Hypertension 下载免费PDF全文
Hien T. T. Duong Zhixia Dong Lin Su Cyrille Boyer Jacob George Thomas P. Davis Jianhua Wang 《Small (Weinheim an der Bergstrasse, Germany)》2015,11(19):2291-2304
Polymeric nanoparticles are designed to transport and deliver nitric oxide (NO) into hepatic stellate cells (HSCs) for the potential treatment of both liver fibrosis and portal hypertension. The nanoparticles, incorporating NO donor molecules (S‐nitrosoglutathione compound), are designed for liver delivery, minimizing systemic delivery of NO. The nanoparticles are decorated with vitamin A to specifically target HSCs. We demonstrate, using in vitro and in vivo experiments, that the targeted nanoparticles are taken up specifically by rat primary HSCs and the human HSC cell line accumulating in the liver. When nanoparticles, coated with vitamin A, release NO in liver cells, we find inhibition of collagen I and α‐smooth muscle actin (α‐SMA), fibrogenic genes associated with activated HSCs expression in primary rat liver and human activated HSCs without any obvious cytotoxic effects. Finally, NO‐releasing nanoparticles targeted with vitamin A not only attenuate endothelin‐1 (ET‐1) which elicites HSC contraction but also acutely alleviates haemodynamic disorders in bile duct‐ligated‐induced portal hypertension evidenced by decreasing portal pressure (≈20%) and unchanging mean arterial pressure. This study clearly shows, for the first time, the potential for HSC targeted nanoparticle delivery of NO as a treatment for liver diseases with proven efficacy for alleviating both liver fibrosis and portal hypertension. 相似文献
999.
Saurabh Das Nadine R. Martinez Rodriguez Wei Wei J. Herbert Waite Jacob N. Israelachvili 《Advanced functional materials》2015,25(36):5840-5847
Mussel adhesion to mineral surfaces is widely attributed to 3,4‐dihydroxyphenylalanine (Dopa) functionalities in the mussel foot proteins (mfps). Several mfps, however, show a broad range (30%–100%) of tyrosine (Tyr) to Dopa conversion suggesting that Dopa is not the only desirable outcome for adhesion. Here, a partial recombinant construct of mussel foot protein‐1 (rmfp‐1) and short decapeptide dimers with and without Dopa are used and both their cohesive and adhesive properties on mica are assessed using a surface forces apparatus. Our results demonstrate that at low pH, both the unmodified and Dopa‐containing rmfp‐1s show similar energies for adhesion to mica and self–self‐interaction. Cohesion between two Dopa‐containing rmfp‐1 surfaces can be doubled by Fe3+ chelation, but remains unchanged with unmodified rmfp‐1. At the same low pH, the Dopa‐modified short decapeptide dimer did not show any change in cohesive interactions even with Fe3+. The results suggest that the most probable intermolecular interactions are those arising from electrostatic (i.e., cation–π) and hydrophobic interactions. It is also shown that Dopa in a peptide sequence does not by itself mediate Fe3+ bridging interactions between peptide films: peptide length is a crucial enabling factor. 相似文献
1000.
Yang Jiao Jacob Fish 《International journal for numerical methods in engineering》2015,104(11):1008-1037
A methodology aimed at addressing computational complexity of analyzing delamination in large structural components made of laminated composites is proposed. The classical ply‐by‐ply discretization of individual layers may increase the size of the problem by an order of magnitude in comparison with the laminated shell or plate element meshes. The paper features delamination indicators that pinpoint the onset and propagation of delamination fronts with striking accuracy. Once the location of delamination has been identified, the discrete solution space of the classical laminated plate/shell element is hierarchically enriched by a combination of weak and strong discontinuities to adaptively track the evolution of delamination fronts. The so‐called adaptive s‐method proposed herein is equivalent in terms of approximation space to the extended finite element method but offers sparser matrices and added flexibility in transitioning from weak to strong discontinuities. Numerical examples suggest that despite an overhead that comes with adaptivity, the adaptive s‐method is computationally advantageous over the classical ply‐by‐ply discretization, especially as the problem size increases. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献