A Novel Treatment of the Josephson Effect

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...     

A Note on the Parallel Runtime of Self-Stabilizing Graph Linearization

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.     

A comparison of inspection practices within the construction industry between the Danish and Swedish Work Environment Authorities

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.     

Development of new hybrid ultrafiltration membranes by entanglement of macromolecular PPSU‐SO3H chains: Preparation,morphologies, mechanical strength,and fouling resistant properties

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 %), R_m (hydraulic resistance), R_c (cake layer resistance), R_p (pore plugging resistance), R_r (reversible fouling), R_ir (irreversible fouling), and FRR (flux recovery ratio). © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41986.     

Personal heating: effectiveness and energy use

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.     

Evaluating Ketoreductase Exchanges as a Means of Rationally Altering Polyketide Stereochemistry

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.     

Ultramild Protein‐Mediated Click Chemistry Creates Efficient Oligonucleotide Probes for Targeting and Detecting Nucleic Acids

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.     

The Use of Nanoparticles to Deliver Nitric Oxide to Hepatic Stellate Cells for Treating Liver Fibrosis and Portal Hypertension

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.