Performance of SCAN density functional for a set of ionic liquid ion pairs

Computational chemistry is a powerful tool for the discovery of novel materials. In particular, it is used to simulate ionic liquids in search of electrolytes for electrochemical applications. Herein, the choice of the computational method is not trivial, as it has to be both efficient and accurate. Density functional theory (DFT) methods with appropriate corrections for the systematic weaknesses can give precision close to that of the post-Hartree--Fock coupled cluster methods with a fraction of their cost. Thence, we have evaluated the performance of a recently developed non-empirical Strongly Constrained and Appropriately Normed (SCAN) density functional on electronic structure calculations of ionic liquid ion pairs. The performance of SCAN and other popular functionals (PBE, M06-L, B2PLYP) among with Grimme's dispersion correction and Boys-Bernardi basis set superposition error correction was compared to DLPNO-CCSD(T)/CBS. We show that SCAN reproduces coupled-cluster results for describing the employed dataset of 48 ion pairs.Comment: 24 pages, 6 figure

Monitoring asthma in childhood : Lung function, bronchial responsiveness and inflammation

Peer reviewedPublisher PD

Perturbative expansions from Monte Carlo simulations at weak coupling: Wilson loops and the static-quark self-energy

Perturbative coefficients for Wilson loops and the static-quark self-energy are extracted from Monte Carlo simulations at weak coupling. The lattice volumes and couplings are chosen to ensure that the lattice momenta are all perturbative. Twisted boundary conditions are used to eliminate the effects of lattice zero modes and to suppress nonperturbative finite-volume effects due to Z(3) phases. Simulations of the Wilson gluon action are done with both periodic and twisted boundary conditions, and over a wide range of lattice volumes (from $3^4$ to $16^4$) and couplings (from $\beta \approx 9$ to $\beta \approx 60$). A high precision comparison is made between the simulation data and results from finite-volume lattice perturbation theory. The Monte Carlo results are shown to be in excellent agreement with perturbation theory through second order. New results for third-order coefficients for a number of Wilson loops and the static-quark self-energy are reported.Comment: 36 pages, 15 figures, REVTEX documen

Phonon-assisted tunneling in asymmetric resonant tunneling structures

Based on the dielectric continuum model, we calculated the phonon assisted tunneling (PAT) current of general double barrier resonant tunneling structures (DBRTSs) including both symmetric and antisymmetric ones. The results indicate that the four higher frequency interface phonon modes (especially the one which peaks at either interface of the emitter barrier) dominate the PAT processes, which increase the valley current and decrease the PVR of the DBRTSs. We show that an asymmetric structure can lead to improved performance.Comment: 1 paper and 5 figure

Unraveling the sperm bauplan: Relationships between sperm head morphology and sperm function in rodents

This is the author accepted manuscript. The final version is available from the Society for the Study of Reproduction via the DOI in this record.Rodents have spermatozoa with features not seen in other species. Sperm heads in many rodent species bear one or more apical extensions known as "hooks." The process by which hooks have evolved, together with their adaptive significance, are still controversial issues. In order to improve our understanding of the biological meaning of these sperm head adaptations, we analyzed hook curvature angles, hook length, and overall hook shape in muroid rodents by using geometric morphometrics. We also searched for relationships between hook design and measurements of intermale competition to assess whether postcopulatory sexual selection was an important selective force driving changes in this sperm structure. Finally, we sought possible links between aspects of sperm hook design and sperm velocity as a measure of sperm performance. Results showed that one hook curvature angle is under strong selective pressure. Similarly, hook length appears to be strongly selected by sexual selection, with this selective force also exhibiting a stabilizing role reducing intermale variation in this trait. The adaptive significance of changes in hook structure was supported by the finding that there are strong and significant covariations between hook dimensions and shape and between hook design and sperm swimming velocity. Overall, this study strongly suggests that postcopulatory sexual selection has an important effect on the design of the sperm head that, in turn, is important for enhancing sperm velocity, a function crucial to reaching the vicinity of the female gamete and winning fertilizations under competitive situations

Brachyspira pilosicoli-induced avian intestinal spirochaetosis

Avian intestinal spirochetosis (AIS) is a common disease occurring in poultry that can be caused by Brachyspira pilosicoli, a Gram-negative bacterium of the order Spirochaetes. During AIS, this opportunistic pathogen colonises the lower gastrointestinal (GI) tract of poultry (principally the ileum, caeca and colon), which can cause symptoms such as diarrhoea, reduced growth rate and reduced egg production and quality. Due to the large increase of bacterial resistance to antibiotic treatment, the European Union banned in 2006 the prophylactic use of antibiotics as growth promoters in livestock. Consequently, the number of outbreaks of AIS has dramatically increased in the UK resulting in significant economic losses. This review summaries the current knowledge about AIS infection caused by B. pilosicoli and discusses various treatments and prevention strategies to control AIS

Monitoring asthma in childhood : symptoms, exacerbations and quality of life

Acknowledgements The Task Force members and their affiliations are as follows. Paul L.P. Brand: Princess Amalia Children’s Centre, Isala Hospital, Zwolle, and UMCG Postgraduate School of Medicine, University Medical Centre and University of Groningen, Groningen, The Netherlands; Mika J. Mäkelä: Skin and Allergy Hospital, Helsinki University Hospital, Helsinki, Finland; Stanley J. Szefler: Children’s Hospital Colorado and University of Colorado Denver School of Medicine, Denver, CO, USA; Thomas Frischer: Dept of Paediatrics and Paediatric Surgery, Wilhelminenspital, Vienna, Austria; David Price: Dept of Primary Care Respiratory Medicine, Academic Primary Care, Division of Applied Health Sciences, University of Aberdeen, Aberdeen, UK; Eugenio Baraldi: Women’s and Children’s Health Dept, Unit of Respiratory Medicine and Allergy, University of Padova, Padova, Italy; Kai-Hakon Carlsen: Dept of Paediatrics, Women and Children’s Division, University of Oslo, and Oslo University Hospital, Oslo, Norway; Ernst Eber: Respiratory and Allergic Disease Division, Dept of Paediatrics and Adolescence Medicine, Medical University of Graz, Graz, Austria; Gunilla Hedlin: Dept of Women’s and Children’s Health and Centre for Allergy Research, Karolinska Institutet, and Astrid Lindgren Children’s hospital, Stockholm, Sweden; Neeta Kulkarni: Leicestershire Partnership Trust and Dept of Infection, Immunity and Inflammation, University of Leicester, Leicester, UK; Christiane Lex: Dept of Paediatric Cardiology and Intensive Care Medicine, Division of Paediatric Respiratory Medicine, University Hospital Goettingen, Goettingen, Germany; Karin C. Lødrup Carlsen: Dept of Paediatrics, Women and Children’s Division, Oslo University Hospital, and Dept of Paediatrics, Faculty of Medicine, University of Oslo, Oslo, Norway; Eva Mantzouranis: Dept of Paediatrics, University Hospital of Heraklion, University of Crete, Heraklion, Greece; Alexander Moeller: Division of Respiratory Medicine, University Children’s Hospital Zurich, Zurich, Switzerland; Ian Pavord: Dept of Respiratory Medicine, University of Oxford, Oxford, UK; Giorgio Piacentini: Paediatric Section, Dept of Life and Reproduction Sciences, University of Verona, Verona, Italy; Mariëlle W. Pijnenburg: Dept Paediatrics/Paediatric Respiratory Medicine, Erasmus MC - Sophia Children’s Hospital, Rotterdam, The Netherlands; Bart L. Rottier: Dept of Pediatric Pulmonology and Allergology, GRIAC Research Institute, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands; Sejal Saglani: Leukocyte Biology and Respiratory Paediatrics, National Heart and Lung Institute, Imperial College London, London, UK; Peter D. Sly: Queensland Children’s Medical Research Institute, The University of Queensland, Brisbane, Australia; Steve Turner: Dept of Paediatrics, University of Aberdeen, Aberdeen, UK; Edwina Wooler: Royal Alexandra Children’s Hospital, Brighton, UK.Peer reviewedPublisher PD

By hook or by crook? Morphometry, competition and cooperation in rodent sperm

Background Sperm design varies enormously across species and sperm competition is thought to be a major factor influencing this variation. However, the functional significance of many sperm traits is still poorly understood. The sperm of most murid rodents are characterised by an apical hook of the sperm head that varies markedly in extent across species. In the European woodmouse Apodemus sylvaticus (Muridae), the highly reflected apical hook of sperm is used to form sperm groups, or “trains,” which exhibited increased swimming velocity and thrusting force compared to individual sperm. Methodology/Principal Findings Here we use a comparative study of murine rodent sperm and demonstrate that the apical hook and sperm cooperation are likely to be general adaptations to sperm competition in rodents. We found that species with relatively larger testes, and therefore more intense sperm competition, have a longer, more reflected apical sperm hook. In addition, we show that sperm groups also occur in rodents other than the European woodmouse. Conclusions Our results suggest that in rodents sperm cooperation is more widespread than assumed so far and highlight the importance of diploid versus haploid selection in the evolution of sperm design and function

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The aim of agricultural research is an abundant supply of high quality food and fiber. There are always new challenges. Following are selected food research projects being conducted by USDA 's Agricultural Research Service