bluuebunny/crossref_metadata_2025 huggingface dataset:
Non‐target site resistance to flucarbazone, imazamethabenz and pinoxaden is controlled by three linked genes in Avena fatua
Authors: Burns E E , Keith B K , Talbert L E , Dyer W E
Published: December 2017

Extensive herbicide usage has led to the evolution of resistant weed populations that cause substantial crop yield losses and increase production costs. The multiple herbicide‐resistant (MHR) Avena fatua populations utilised in this study are resistant to members of all selective herbicide families, across five modes of action, available for A. fatua control in US small grain production, and thus pose significant agronomic and economic threats. Resistance to acetolactate synthase and acetyl‐CoA carboxylase inhibitors is not conferred by known target site mutations, indicating that non‐target site resistance (NTSR) mechanisms are involved. Understanding the inheritance of NTS MHR is of upmost importance for continued agricultural productivity in the face of the rapid increase in resistant weed populations worldwide. As few studies have examined the inheritance of NTSR in autogamous weeds, we investigated the inheritance and genetic control of NTSR in the highly autogamous, allohexaploid species A. fatua. We found that NTSR in MHRA. fatua is controlled by three separate, closely‐linked nuclear genes for flucarbazone‐sodium, imazamethabenz‐methyl and pinoxaden. The single‐gene NTSR inheritance patterns reported here contrast with other examples in allogamous species and illustrate the diversity of evolutionary responses to strong selection.
Role, ownership and presence of domestic animals in peri‐urban households of Kisumu, Kenya
Authors: Barnes A. N. , Mumma J. , Cumming O.
Published: December 2017

Low‐ and middle‐income countries are experiencing rapid urban population growth, particularly in peri‐urban informal settlements. In these urban areas, animal husbandry remains a valuable source of income and protein‐rich foods but may also present a risk of zoonotic disease threat. To date, there have been studies that have assessed the prevalence and nature of animal ownership in these communities. This cross‐sectional survey assessed the geographical, sociocultural and economic factors behind the presence, ownership and purpose of domestic animals in three informal peri‐urban communities of Kisumu, Kenya. A majority (n = 587) of the study households exhibited domestic animal presence in the living space yet only 32% of households reported animal ownership (n = 252). The purposes of ownership included: for meat/eggs (55%); for income, sale or trade (43%); for milk production (31%); and as companions/pets (31%). Among households that owned animals, 76% reported that at least one animal slept in the house at night. In multivariate logistic regression, the following factors were significantly associated with household animal ownership: ownership of agricultural land (OR = 1.94, 95% CI = 1.12, 3.35), perceiving a strong community bond (OR = 2.28, 95% CI = 1.25, 4.16), and household membership in a community group (OR = 1.64, 95% CI = 1.04, 2.60). This research demonstrates the high prevalence of animal ownership in a low‐income and high‐density peri‐urban neighbourhood of an African city, which may facilitate zoonotic disease transmission. Further research should assess if and to what extent animal ownership in such communities is associated with disease risk.
Analysis of Carbon Tax on Selected European Countries: Does Carbon Tax Reduce Emissions?
Authors: Alper Ali Eren
Published: December 2017

Since the first days of its existence, the humanity had been using natural resources to meet its needs. Especially along with the globalization period as a result of the Industrial Revolution and the rapid development of communication technologies within the last fifty years, the production has increased significantly in the world and has created negative effects on the environment. The leading adverse effects involve the emission of greenhouse gases and the global warming, which stem from the energy supply of fossil fuels as the main inputs of production. The global warming can be described as an increase in temperature worldwide. Irreversibility is the most important feature of the global warming. Therefore, in the absence of objective measures, the future costs would be much higher than the current ones. For this reason, governments need to take various measures to reduce the volume of emissions. The most important of these measures is carbon taxes. Carbon taxation encourages individuals to use fewer fossil fuels and to find new sources of energy by increasing the cost of using fossil fuels that cause carbon dioxide emissions through the price mechanism. To this end, the impacts of carbon tax levied in 18 selected European countries on economic growth, urbanization, natural gas and petroleum usage, and CO2 emissions are examined by panel data analysis for the 1995-2015 period. The analysis results indicate that a 1% increase in environmental taxes reduces carbon dioxide emissions by 0.9%. Furthermore, it is reported that a 1% increase in natural gas and petroleum consumption among the variables included in the analysis increased carbon dioxide emissions by 0.1% and 0.7%, respectively; while a 1% increase in urbanization reduced carbon dioxide emissions by 0.9%.
Molecular and functional characterization of inwardly rectifying K+ currents in murine proximal colon
Authors: Huang Xu , Lee Si Hyung , Lu Hongli , Sanders Kenton M. , Koh Sang Don
Published: December 2017

Key points

Interstitial cells of Cajal (ICC) from murine colonic muscles express genes encoding inwardly rectifying K+ channels. Transcripts of Kcnj2 (Kir2.1), Kcnj4 (Kir2.3), Kcnj14 (Kir2.4), Kcnj5 (Kir3.4), Kcnj8 (Kir 6.1) and Kcnj11 (Kir6.2) were found in colonic ICC.

A conductance with properties consistent with Kir2 channels was observed in ICC but not in smooth muscle cells (SMC).

Despite expression of gene transcripts, G‐protein gated K+ channel (Kir3) and KATP (Kir6) currents were not resolved in ICC. KATP is a conductance prominent in SMC.

Kir2 antagonist caused depolarization of freshly dispersed ICC and colonic smooth muscles, suggesting that this conductance is active under resting conditions in colonic muscles.

The conclusion of the present study is that ICC express the Ba2+‐sensitive, inwardly rectifying K+ conductance in colonic muscles. This conductance is most probably a result of heterotetramers of Kir2 gene products, with this regulating resting potentials and the excitability of colonic muscles.

Membrane potentials of gastrointestinal muscles are important because voltage‐dependent Ca2+ channels in smooth muscle cells (SMC) provide the Ca2+ that triggers contraction. Regulation of membrane potential is complicated because SMC are electrically coupled to interstitial cells of Cajal (ICC) and PDGFRα+ cells. Activation of conductances in any of these cells affects the excitability of the syncytium. We explored the role of inward rectifier K+ conductances in colonic ICC that might contribute to regulation of membrane potential. ICC expressed Kcnj2 (Kir2.1), Kcnj4 (Kir2.3), Kcnj14 (Kir2.4), Kcnj5 (Kir3.4), Kcnj8 (Kir 6.1) and Kcnj11 (Kir6.2). Voltage clamp experiments showed activation of inward current when extracellular K+ ([K+]o) was increased. The current was inwardly rectifying and inhibited by Ba2+ (10 μm) and ML‐133 (10 μm). A similar current was not available in SMC. The current activated in ICC by elevated [K+]o was not affected by Tertiapin‐Q. Gβγ, when dialysed into cells, failed to activate a unique, Tertiapin‐Q‐sensitive conductance. Freshly dispersed ICC showed no evidence of functional KATP. Pinacidil failed to activate current and the inward current activated by elevated [K+]o was insensitive to glibenclamide. Under current clamp, ML‐133 caused the depolarization of isolated ICC and also that of cells impaled with microelectrodes in intact muscle strips. These findings show that ICC, when isolated freshly from colonic muscles, expressed a Ba2+‐sensitive, inwardly rectifying K+ conductance. This conductance is most probably a result of the expression of multiple Kir2 family paralogues, and the inwardly rectifying conductance contributes to the regulation of resting potentials and excitability of colonic muscles.
An Ensemble Monte Carlo Simulation Study of Water Distribution in Porous Gas Diffusion Layers for Proton Exchange Membrane Fuel Cells
Authors: Capone Luigino , Marmet Philip , Holzer Lorenz , Dujc Jaka , Schumacher Jürgen O. , Lamibrac Adrien , Büchi Felix N. , Becker Jürgen
Published: December 2017

Water management in proton-exchange membrane fuel cells (PEFCs) has a large impact on the performance of the device, as liquid water affects the transport properties of the gas diffusion layer (GDL). In this study, we develop an ensemble-based model of the liquid water distribution inside the GDL. Based on a water injection experiment, the wet structure of the porous medium is inspected via X-ray tomographic microscopy and, after an image segmentation process, a voxel-based meshing of the fiber, air, and water domains is obtained. Starting from the obtained dry fiber structure, a Metropolis-Hastings Monte Carlo algorithm is used to obtain the equilibrium distribution of liquid water that minimizes the surface free energy of the ensemble. The different water distributions from the Monte Carlo (MC) simulation and water injection experiment are identified as solution for different physical mechanisms both of which are present in a running fuel cell. The wet structure is then used to calculate saturation-dependent effective transport properties using the software geodict. Thereby, a strong influence of the saturation gradient on the macrohomogeneous transport properties is found.
Tribological Properties of Textured Cemented Carbide Surfaces of Different Wettability Produced by Pulse Laser
Authors: Hao Xiuqing , Li Hanlong , Song Xiaolu , Li Liang , He Ning
Published: December 2017

The micro/nanotextured cemented carbide surface of different wettability was produced by laser scanning and fluorinated treatment. The tribological properties of the untextured, oleophobic and oleophilic micro/nanotextured surface were investigated experimentally including the effects of crank speed and contact pressure by a reciprocating friction and a wear tester. For all tested surfaces, the friction coefficient of the surface decreased as both the increasing crank speed and contact pressure increased. Compared to the untextured surface, the friction coefficient of the micro/nanotextured surface was significantly decreased, being sensitive to the wettability of the surface. Besides, the tribological properties of the oleophobic micro/nanotextured surface were superior to the oleophilic micro/nanotextured surface under the same experimental conditions. The improvement in tribological properties of the oleophobic micro/nanotextured surface could be attributed to the low wettability, which was beneficial to rapid accumulation of the lubricating oil on the surface.
Characteristic Time Constants Derived From the Low-Frequency Arc of Impedance Spectra of Fuel Cell Stacks
Authors: Keller Stefan , Özel Tansu , Scherzer Anne-Christine , Gerteisen Dietmar , Groos Ulf , Hebling Christopher , Manoli Yiannos
Published: December 2017

Electrochemical impedance spectroscopy is used during operation of different polymer electrolyte membrane fuel cell (PEMFC) stack assemblies at various conditions with special interest given to the characteristic time constant τlow-f derived from the low-frequency arc of the spectra which is typically in the range of approximately 15–0.5 Hz. This was done by fitting an equivalent electrical circuit (EEC) consisting of one resistor and two RC-elements to the data. Parameter variation performed on a 90-cell stack assembly suggests that conditions leading to different air flow velocities in the flow channels affect τlow-f while other parameters like humidity influence the impedance spectrum, but not τlow-f. Comparison of the stoichiometry variation between short stack and locally resolved single cell shows similar results with the stack's time constant matching that of the cell's segments which are located off-center toward the outlet. However, a nonlinear dependency between gas flow velocity and τlow-f especially at low stoichiometric values is obvious. Results from stoichiometry variations at different pressure levels suggest that this could be attributed to the different steady-state oxygen partial pressures during the experiments. Comparison of the stoichiometry variation between different stack platforms result in similar dependencies of τlow-f on air flow rate with respect to a reference oxygen partial pressure regardless of size, flow field, geometry, or cell count of the stack. The time constant caused by oxygen diffusion through the gas diffusion layer (GDL), τGDL, was approximated and compared to τlow-f. While it was found that τlow-f ≫ τGDL at low stoichiometric values, τlow-f decreases toward τGDL at very high gas flow rates, suggesting that τGDL offsets τlow-f and becomes dominating if no oxygen concentration variation along the flow channel was present.
Oil/Water Correlation for PRV (Pressure Relief Valves): Is the Measured Set Pressure the Same on Water Compared to Diesel Fuel, Lubricating Oil, etc.?
Authors: O’Neill Robert J.
Published: December 2017

In verifying PRV setpoints, it is important to distinguish if there is any differential (±) between the measured SP (Set Pressure) of a PRV when tested on water versus testing on other fluids such as Diesel Fuel or Lubricating Oil. It is also important to recognize the standard test medium used by the PRV industry for liquid service testing is water. SP testing with other fluids involves issues such as possible serious health and safety as well as equipment cross contamination.

Paper published with permission.
Inservice Testing for Small Modular Nuclear Reactor Plants
Authors: McGee Gary P. , Unikewicz Steven M.
Published: December 2017

The American Society of Mechanical Engineers (ASME) Operation and Maintenance of Nuclear Power Plants, Division 1, “OM Code: Section IST,” defines a post-2000 plant as a nuclear power plant that was issued (or will be issued) its construction permit, or combined license for construction and operation, by the applicable regulatory authority on or following January 1, 2000.

The NuScale advanced small modular reactor plant is passive, pressurize water reactor, designed such that from one (1) to twelve (12) nuclear power plant modules (NPM) can operate within a single Reactor Building. Each NuScale Power Module (NPM) consist of a reactor core, two steam generator tube bundles, and a pressurizer contained within a single reactor vessel, along with the containment vessel that immediately surrounds the reactor vessel and is rated at 160 MWt.

The ASME Operation and Maintenance (OM) Code was written considering single-unit reactor plants, not multi-modular SMRs. The ASME Sub-Committee, New Reactors is developing a new Sub-Section, ISTG to address inservice testing (IST) of valves for all new and advanced reactor types.

This paper reviews the unique aspects and programmatic solutions for preservice testing (PST) and IST specific to the NuScale small modular reactor (SMR). The functional design, qualification provisions and IST program is described. The PST and preservice test period will be discussed as some preservice testing may be completed in the factory prior to shipping the reactor module to the site. Additionally, methods eliminate overlap, redundancy and excessive testing between the preservice testing (PST) and IST program plans will be explored.

The intent of these solutions is to provide reasonable assurance that the ASME BPV Code, Section III Class 1, Class 2, Class 3, non-safety-related and non-ASME valves that have an important function will operate when needed. The program considers both deterministic and risk insights in its evaluation of PST and IST and meets the requirements of the ASME OM Code as endorsed by 10 CFR 50.55a.

Paper published with permission.
Curtiss-Wright Advanced NozzleCheck Valves for Generation III+ Nuclear Power Plants
Authors: Mkrtchyan Haykaz , Torosyan Ararat , Apelian Tsolag
Published: December 2017

Curtiss Wright introduced the first Normally Open NozzleCheck valves to the nuclear power industry nearly 20 years ago. This passive valve design was developed to address reoccurring maintenance and reliability issues often experienced by various check valve types due to low flow conditions. Specifically, premature wear on the hinge pins, bushings and severe seat impact damage had been discovered in several applications while the systems were in steady state operating conditions.

Over the last two decades, Curtiss Wright has continued to improve upon the design of the valve, with the latest generation coming most recently in support of the Westinghouse AP1000 design and similar Generation III+ passive reactor requirements. This entirely new valve is designed with minimal stroke, ensuring quick closure under specified reverse flow conditions which no other check valve design could support. Additionally, features such as first in kind test ports, visual inspection points, and the ability to stroke the valve manually or with system fluid in line have resolved many of the shortcomings of previous inline welded flow check valves.

Most importantly, advanced test based methodologies and models developed by Curtiss Wright, allow for accurate prediction of NozzleCheck valve performance. This paper presents the development of Curtiss Wright’s advanced Normally Open NozzleCheck Valve for Generation III and III+ nuclear reactor designs. The Valve performance was initially determined by using verified and validated computational fluid dynamic (CFD) methods. The results obtained from the CFD model were then compared to the data gathered from a prototype valve that was built and tested to confirm the performance predictions. Curtiss Wright has fully tested and qualified the Normally Open NozzleCheck valve, which is specifically designed for applications that require a high capacity in the forward flow direction and a closure at low flow rates with short stroke to minimize the hydraulic impact on the system.

Paper published with permission.
Influence of N2/H2 and N2 plasma on binary III-nitride films prepared by hollow-cathode plasma-assisted atomic layer deposition
Authors: Alevli Mustafa , Gungor Nese
Published: December 2017

The authors reported the hollow-cathode plasma-assisted atomic layer deposition of AlN, GaN, and InN films using N2-only and N2/H2 plasma. In this study, the authors analyzed the effect of plasma gas composition on the properties of deposited binary III-nitride thin films. Toward this goal, AlN, GaN, and InN films were deposited on Si (100) substrates using N2-only (50 sccm), as well as N2/H2 (50 + 50, 50 + 25 sccm) plasma to investigate the impact of H2 flow. Grazing-incidence x-ray diffraction (GIXRD) patterns of AlN and GaN thin films deposited with N2/H2 plasma remained almost unchanged when H2 flow decreased from 50 to 25 sccm. On the other hand, the use of N2 plasma without any H2 resulted in amorphous GaN thin films with significant carbon impurity within the bulk film. In the case of AlN, similar behavior was observed as the crystal structure is significantly altered to amorphouslike material. Thicknesses of AlN and GaN thin films increased tremendously when N2-only was used as the plasma gas. Furthermore, refractive index values of both AlN and GaN films decreased upon the use of N2-only plasma, which confirm the deterioration of the film quality. Structural weaknesses of GaN and AlN films deposited with N2-only plasma are due to presences of carbon impurities that are trapped inside the growing film. Interestingly, the authors did not observe similar results in InN films grown with N2/H2 plasma. For InN, GIXRD and spectroscopic ellipsometry results show that the phases of deposited films change from InN to In+InN as H2 content in the plasma gas is increased. On the other hand, InN films grown with N2-only plasma show improved structural properties. However, significantly higher N2 plasma exposure times are needed to minimize the residual carbon content in deposited InN layers.
Gastric mucus and mucuslike hydrogels: Thin film lubricating properties at soft interfaces
Authors: Røn Troels , Patil Navin J. , Ajalloueian Fatemeh , Rishikesan Sankaranarayanan , Zappone Bruno , Chronakis Ioannis S. , Lee Seunghwan
Published: December 2017

Mucus is a viscous slime that plays a vital role in protecting and lubricating biological tissues, in particular, soft epithelium interfaces such as in the stomach, intestines, and esophagus. Previous attempts to generate mucus models that mimick or simulate its characteristics have been predominantly focused on the rheological properties. This study investigates both rheological and tribological shear properties of thin films of gastric mucus from a porcine source and its mimics at compliant soft interfaces. The lubricating efficacy of biological mucus and its mimics was observed to be superior at hydrophilic tribological interfaces compared to hydrophobic ones. Facile spreading of all mucus samples at hydrophilic steel–polydimethylsiloxane (PDMS) interfaces allowed for the retainment of the lubricating films over a wide range of speed, slide/roll ratio, and external load. In contrast, poor wetting at hydrophobic PDMS–PDMS interfaces led to depletion of the mucus samples from the interface with increasing speed. Among the different mucus models investigated in this study, fluid mixtures of commercially available porcine gastric mucin (PGM) and polyacrylic acid (PAA) displayed the most persistent lubricating effects under various tribological experimental conditions. A mixture of PGM and PAA holds a high potential as mucus mimic, not only for its rheological similarity, but also for its excellent lubricity in soft compliant and hydrophilic contacts.
Optimization of pyroelectric electron sources for the generation of x-rays for x-ray fluorescence applications
Authors: Wilke Markus , Harnisch Karsten , Knapp Wolfram , Ecke Martin , Halle Thorsten
Published: December 2017

X-ray fluorescence (XRF) spectroscopy is a frequently used technique for the chemical analysis of materials due to several advantages such as its almost nondestructive character. Subjects of this report are investigations of the pyroelectric effect with regard to its application for the generation and acceleration of x-rays and a successive usage of radiation for XRF in materials science. In order to answer questions concerning the intensity of primary radiation and of fluorescence radiation, this paper contains several experimental investigations. Different setups and measurements have been used to increase intensity. Emission behavior of electrons has been characterized using measurements of electron current in a target positioned in front of a pyroelectric crystal as a function of the temperature of the crystal and time. Radiation has been coupled out, and its dose equivalent rate has been measured. This allowed the optimization of the working pressure of the residual gas surrounding the crystal in an evacuated atmosphere (rarefied air). It has been shown that a vacuum pressure of approximately 5 × 10−1 Pa allows the generation of radiation with high intensities. Different target materials have been compared due to the intensity of excited fluorescence radiation of a sample by using an energy dispersive radiation detector. A qualitative and quantitative analysis of elements contained in the sample has been proven to be feasible. A possible application of the radiation for imaging has been investigated.
Energy, momentum, and angular momentum of sound pulses
Authors: Lekner John
Published: December 2017

Pulse solutions of the wave equation can be expressed as superpositions of scalar monochromatic beam wavefunctions (solutions of the Helmholtz equation). This formulation leads to causal (unidirectional) propagation, in contrast to all currently known closed-form solutions of the wave equation. Application is made to the evaluation of the energy, momentum, and angular momentum of acoustic pulses, as integrals over the beam and pulse weight functions. Equivalence is established between integration over space of the energy, momentum, and angular momentum densities, and integration over the wavevector weight function. The inequality linking the total energy and the total momentum is made explicit in terms of the weight function formulation. It is shown that a general pulse can be viewed as a superposition of phonons, each with energy ℏck, z component of momentum ℏq, and z component of angular momentum ℏm. A closed-form solution of the wave equation is found, which is localized and causal, and its energy and momentum are evaluated explicitly.
IL-33 and ST2 mediate FAK-dependent antitumor immune evasion through transcriptional networks
Authors: Serrels Bryan , McGivern Niamh , Canel Marta , Byron Adam , Johnson Sarah C. , McSorley Henry J. , Quinn Niall , Taggart David , Von Kreigsheim Alex , Anderton Stephen M. , Serrels Alan , Frame Margaret C.
Published: December 2017

The kinase FAK coordinates chromatin modifiers and transcription factors to orchestrate evasion of antitumor immune responses.
Antenatal corticosteroids in impending preterm deliveries before 25 weeks’ gestation
Authors: Deshmukh Mangesh , Patole Sanjay
Published: December 2017

Antenatal corticosteroid (ANC) use before 25 weeks’ gestation is controversial. Our previous systematic review (eight observational studies, n=10 109) showed that ANC exposure was associated with significantly reduced mortality and severe intraventricular haemorrhage (IVH)/periventricular leukomalacia (PVL) in neonates born <25 weeks. We update our review by adding data (n=3334) from a recent study. We used Cochrane methodology and summarised the results using GRADE (The Grading of Recommendations Assessment, Development and Evaluation) guidelines. Nine high-quality observational studies were included. Meta-analysis (random effects model) showed reduced mortality (n=13 443; OR=0.48 (95% CI 0.42 to 0.55) P<0.00001; level of evidence (LOE): moderate) and IVH or PVL (n=8418; OR=0.70 (95% CI 0.63 to 0.79), P<0.00001; LOE: moderate) in neonates born <25 weeks exposed to ANC. There was no difference in necrotising enterocolitis (NEC) ≥stage II (n=8737; OR=1.01 (95% CI 0.84 to 1.22), P=0.89; LOE: low); incidence of chronic lung disease (CLD) was higher (n=7983; OR=1.32 (95% CI 1.04 to 1.67), P=0.02; LOE: low) in ANC group. Composite outcomes of death/major morbidities (eg, severe IVH, NEC, CLD) were improved after ANC exposure.
Haemodynamic effects of umbilical cord milking in premature sheep during the neonatal transition
Authors: Blank Douglas A , Polglase Graeme R , Kluckow Martin , Gill Andrew William , Crossley Kelly J , Moxham Alison , Rodgers Karyn , Zahra Valerie , Inocencio Ishmael , Stenning Fiona , LaRosa Domeic A , Davis Peter G , Hooper Stuart B
Published: December 2017

Objective

Umbilical cord milking (UCM) at birth may benefit preterm infants, but the physiological effects of UCM are unknown. We compared the physiological effects of two UCM strategies with immediate umbilical cord clamping (UCC) and physiological-based cord clamping (PBCC) in preterm lambs.

Methods

At 126 days’ gestational age, fetal lambs were exteriorised, intubated and instrumented to measure umbilical, pulmonary and cerebral blood flows and arterial pressures. Lambs received either (1) UCM without placental refill (UCMwoPR); (2) UCM with placental refill (UCMwPR); (3) PBCC, whereby ventilation commenced prior to UCC; or (4) immediate UCC. UCM involved eight milks along a 10 cm length of cord, followed by UCC.

Results

A net volume of blood was transferred into the lamb during UCMwPR (8.8 mL/kg, IQR 8–10, P=0.01) but not during UCMwoPR (0 mL/kg, IQR −2.8 to 1.7) or PBCC (1.1 mL/kg, IQR −1.3 to 4.3). UCM had no effect on pulmonary blood flow, but caused large fluctuations in mean carotid artery pressures (MBP) and blood flows (CABF). In UCMwoPR and UCMwPR lambs, MBP increased by 12%±1% and 8%±1% and CABF increased by 32%±2% and 15%±2%, respectively, with each milk. Cerebral oxygenation decreased the least in PBCC lambs (17%, IQR 13–26) compared with UCMwoPR (26%, IQR 23–25, P=0.03), UCMwPR (35%, IQR 27–44, P=0.02) and immediate UCC (34%, IQR 28–41, P=0.02) lambs.

Conclusions

UCMwoPR failed to provide placental transfusion, and UCM strategies caused considerable haemodynamic disturbance. UCM does not provide the same physiological benefits of PBCC. Further review of UCM is warranted before adoption into routine clinical practice.
Association between hospitalisation for ambulatory care-sensitive conditions and primary health care physician specialisation: a cross-sectional ecological study in Curitiba (Brazil)
Authors: Afonso Marcelo P D , Shimizu Helena E , Merchan-Hamann Edgar , Ramalho Walter M , Afonso Tarcisio
Published: December 2017

Introduction

Hospitalisation for ambulatory care-sensitive conditions (HACSCs) is frequently used as an indicator of the quality and effectiveness of primary healthcare (PHC) services around the world. The aim of the present study was to evaluate whether the PHC model (family health strategy (FHS) x conventional) and the availability of specialised PHC physicians is associated or not with total hospitalisation or HACSCs in the National Health System (SUS) of the municipality of Curitiba, Paraná state (PR), Brazil.

Methodology

This is a cross-sectional ecological study using multiple linear regression with socioeconomic and professional data from municipal health units (MHUs) between 1 April 2014 and 31 March 2015.

Results

After adjustment for age and sex and control of socioeconomic variables, the FHS model was associated with six fewer HACSCs a year per 10 000 inhabitants in relation to the conventional model and the availability of one family physician at each FHS model MHU per 10 000 inhabitants was associated with 1.1 fewer HACSCs for heart failure a year per 10 000 inhabitants. Basic specialists (clinicians, paediatricians and obstetrician/gynaecologists) and subspecialists showed no significant association with HACSC rates.

Conclusion

These results obtained in a major Brazilian city reinforce the role of FHS as a priority PHC model in the country and indicate the potentially significant impact of specialising in family medicine on improving the health conditions of the population.
Association between exercise and the risk of dementia: results from a nationwide longitudinal study in China
Authors: Zhou Zi , Fu Jian , Hong Y. Alicia , Wang Ping , Fang Ya
Published: December 2017

Objective

This study was conducted to examine the causal association between exercise and the risk of dementia among older Chinese adults.

Design

Longitudinal population-based study with a follow-up duration of 9 years.

Setting

Data for the Chinese Longitudinal Healthy Longevity Survey waves occurring from 2002 to 2011–2012 were extracted from the survey database.

Participants

In total, 7501 dementia-free subjects who were older than 65 years were included at baseline. Dementia was defined as a self-reported or proxy-reported physician’s diagnosis of the disease.

Outcome measures and methods

Regular exercise and potential confounding variables were obtained via a self-report questionnaire. We generated longitudinal logistic regression models based on time-lagged generalised estimating equation to examine the causal association between exercise and dementia risk.

Results

Of the 7501 older Chinese people included in this study, 338 developed dementia during the 9-year follow-up period after excluding those who were lost to follow-up or deceased. People who regularly exercised had lower odds of developing dementia (OR=0.53, 95% CI 0.33 to 0.85) than those who did not exercise regularly.

Conclusion

Regular exercise was associated with decreased risk of dementia. Policy-makers should develop effective public health programmes and build exercise-friendly environments for the general public.
Stigma towards mental illness among medical and nursing students in Singapore: a cross-sectional study
Authors: Chang Sherilyn , Ong Hui Lin , Seow Esmond , Chua Boon Yiang , Abdin Edimansyah , Samari Ellaisha , Teh Wen Lin , Chong Siow Ann , Subramaniam Mythily
Published: December 2017

Objectives

To assess stigma towards people with mental illness among Singapore medical and nursing students using the Opening Minds Stigma Scale for Health Care Providers (OMS-HC), and to examine the relationship of students’ stigmatising attitudes with sociodemographic and education factors.

Design and setting

Cross-sectional study conducted in Singapore

Participants

The study was conducted among 1002 healthcare (502 medical and 500 nursing) students during April to September 2016. Students had to be Singapore citizens or permanent residents and enrolled in public educational institutions to be included in the study. The mean (SD) age of the participants was 21.3 (3.3) years, with the majority being females (71.1%). 75.2% of the participants were Chinese, 14.1% were Malays, and 10.7% were either Indians or of other ethnicity.

Methods

Factor analysis was conducted to validate the OMS-HC scale in the study sample and to examine its factor structure. Descriptive statistics and multivariate linear regression were used to examine sociodemographic and education correlates.

Results

Factor analysis revealed a three-factor structure with 14 items. The factors were labelled as attitudes towards help-seeking and people with mental illness, social distance and disclosure. Multivariable linear regression analysis showed that medical students were found to be associated with lower total OMS-HC scores (P<0.05), less negative attitudes (P<0.001) and greater disclosure (P<0.05) than nursing students. Students who had a monthly household income of below S$4000 had more unfavourable attitudes than those with an income of SGD$10 000 and above (P<0.05). Having attended clinical placement was associated with more negative attitudes (P<0.05) among the students.

Conclusion

Healthcare students generally possessed positive attitudes towards help-seeking and persons with mental illness, though they preferred not to disclose their own mental health condition. Academic curriculum may need to enhance the component of mental health training, particularly on reducing stigma in certain groups of students.
Correlates of compliance with national comprehensive smoke-free laws
Authors: Peruga Armando , Hayes Luminita S , Aguilera Ximena , Prasad Vinayak , Bettcher Douglas W
Published: December 2017

Objective

To explore correlates of high compliance with smoking bans in a cross-sectional data set from the 41 countries with national comprehensive smoke-free laws in 2014 and complete data on compliance and enforcement.

Methods

Outcome variable: compliance with a national comprehensive smoke-free law in each country was obtained for 2014 from the WHO global report on the global tobacco epidemic. Explanatory variables: legal enforcement requirements, penalties, infrastructure and strategy were obtained through a separate survey of governments. Also, country socioeconomic and demographic characteristics including the level of corruption control were included. Analysis: an initial bivariate analysis determined the significance of each potentially relevant explanatory variable of high compliance. Differences in compliance were tested using the exact logistic regression.

Results

High compliance with the national comprehensive smoke-free law was associated with the involvement of the local jurisdictions in providing training and/or guidance for inspections (OR=10.3, 95% CI 1.7 to 117.7) and a perception of high corruption control efforts in the country (OR=7.2, 95% CI 1.1 to 85.8).

Discussion

The results show the importance of the depth of the enforcement infrastructure and effort represented by the degree to which the local government is involved in enforcement. They also show the significance of fighting corruption in the enforcement process, including the attempts of the tobacco industry to undermine the process, to achieve high levels of compliance with the law. The results point out to the need to invest minimal but essential enforcement resources given that national comprehensive smoke-free laws are self-enforcing in many but not all countries and sectors.
A new form of nicotine retailers: a systematic review of the sales and marketing practices of vape shops
Authors: Lee Joseph G L , Orlan Elizabeth N , Sewell Kerry B , Ribisl Kurt M
Published: December 2017

Objective

Retailers that primarily or exclusively sell electronic cigarettes (e-cigarettes) or vaping products represent a new category of tobacco retailer. We sought to identify (a) how vape shops can be identified and (b) sales and marketing practices of vape shops.

Data sources

A medical librarian iteratively developed a search strategy and in February 2017 searched seven academic databases (ABI/INFORM Complete, ECONLit, Embase, Entrepreneurship, PsycINFO, PubMed/MEDLINE and Scopus). We hand searched Tobacco Regulatory Science and Tobacco Prevention & Cessation.

Study selection

We used dual, independent screening. Records were eligible if published in 2010 or later, were peer-reviewed journal articles and focused on vape shops.

Data extraction

We used dual, independent data abstraction and assessed risk of bias. Of the 3605 records identified, 22 were included.

Data synthesis

We conducted a narrative systematic review. Researchers relied heavily on Yelp to identify vape shops. Vape shop owners use innovative marketing strategies that sometimes diverge from those of traditional tobacco retailers. Vape shop staff believe strongly that their products are effective harm-reduction products. Vape shops were more common in areas with more White residents.

Conclusions

Vape shops represent a new type of retailer for tobacco products. Vape shops have potential to promote e-cigarettes for smoking cessation but also sometimes provide inaccurate information and mislabelled products. Given their spatial patterning, vape shops may perpetuate inequities in tobacco use. The growing literature on vape shops is complicated by researchers using different definitions of vape shops (eg, exclusively selling e-cigarettes vs also selling traditional tobacco products).
Lactate is oxidized outside of the mitochondrial matrix in rodent brain
Authors: Herbst Eric A.F. , George Mitchell A.J. , Brebner Karen , Holloway Graham P. , Kane Daniel A.
Published: December 2017

The nature and existence of mitochondrial lactate oxidation is debated in the literature. Obscuring the issue are disparate findings in isolated mitochondria, as well as relatively low rates of lactate oxidation observed in permeabilized muscle fibres. However, respiration with lactate has yet to be directly assessed in brain tissue with the mitochondrial reticulum intact. To determine if lactate is oxidized in the matrix of brain mitochondria, oxygen consumption was measured in saponin-permeabilized mouse brain cortex samples, and rat prefrontal cortex and hippocampus (dorsal) subregions. While respiration in the presence of ADP and malate increased with the addition of lactate, respiration was maximized following the addition of exogenous NAD+, suggesting maximal lactate metabolism involves extra-matrix lactate dehydrogenase. This was further supported when NAD+-dependent lactate oxidation was significantly decreased with the addition of either low-concentration α-cyano-4-hydroxycinnamate or UK-5099, inhibitors of mitochondrial pyruvate transport. Mitochondrial respiration was comparable between glutamate, pyruvate, and NAD+-dependent lactate oxidation. Results from the current study demonstrate that permeabilized brain is a feasible model for assessing lactate oxidation, and support the interpretation that lactate oxidation occurs outside the mitochondrial matrix in rodent brain.
Trace lithium in Texas tap water is negatively associated with all-cause mortality and premature death
Authors: Fajardo Val Andrew , LeBlanc Paul J. , Fajardo Val Andrei
Published: December 2017

Lithium in tap water was previously found to have life-extending effects across 18 Japanese municipalities. Using a larger dataset with several Texas counties, our study shows that lithium concentrations in tap water are negatively associated with all-cause mortality (r = −0.18, p = 0.006, 232 counties) and years of potential life lost (r = −0.22, p = 0.001, 214 counties). Thus, our present findings extend and reinforce lithium’s purported life-prolonging effect in humans.
Synthesis and characterization of methyl substituted 3-hydroxypyridin-4-ones and their complexes with iron(III)
Authors: Cheng Chen , Chen Yulin , Cao Yue , Ma Yongmin , Hider Robert C.
Published: December 2017

Methyl substituted 3-hydroxypyridin-4(1H)-ones have been synthesized. The pKa values and Fe3+ affinity constants of these ligands were studied. The introduction of an electron-donating methyl group at a different position of pyridinone ring markedly influences the pKa values of 3-hydroxy and 4-oxo groups. The pFe3+ values were also affected and are in the range of 17.6–20.7. The findings can be used to guide a design of 3-hydroxypyridin-4-ones with desirable pKa and pFe3+ values.
Abelian p-extensions and additive polynomials
Authors: Barreto-Castañeda Jonny Fernando , Jarquín-Zárate Fausto , Rzedowski-Calderón Martha , Villa-Salvador Gabriel
Published: December 2017

In this work, we present some arithmetic properties of families of abelian [Formula: see text]-extensions of global function fields, among which are their generators and their type of ramification and decomposition.
Abelian ideals and amazing roots
Authors: Panyushev Dmitri I.
Published: December 2017

Let [Formula: see text] be a simple Lie algebra with a Borel subalgebra [Formula: see text]. To any long positive root [Formula: see text], one associates two ideals of [Formula: see text]: the abelian ideal [Formula: see text] and not necessarily abelian ideal [Formula: see text]. It is known that [Formula: see text], and [Formula: see text] is said to be amazing if the equality holds. The set of amazing roots, [Formula: see text], is closed under the operation “∨” in [Formula: see text], and [Formula: see text] is said to be primitive, if it cannot be written as [Formula: see text] with incomparable amazing roots [Formula: see text]. We classify the amazing roots and notice that the number of primitive roots equals [Formula: see text]. Moreover, if [Formula: see text] (respectively, [Formula: see text]) is the set of simple (respectively, primitive) roots, then there is a natural bijection [Formula: see text]. We also study the subset [Formula: see text] of [Formula: see text].
Holomorphic correspondences related to finitely generated rational semigroups
Authors: Bharali Gautam , Sridharan Shrihari
Published: December 2017

In this paper, we present a new technique for studying the dynamics of a finitely generated rational semigroup. Such a semigroup can be associated naturally to a certain holomorphic correspondence on [Formula: see text]. Results on the iterative dynamics of such a correspondence can now be applied to the study of the rational semigroup. We focus on an invariant measure for the aforementioned correspondence — known as the equilibrium measure. This confers some advantages over many of the known techniques for studying the dynamics of rational semigroups. We use the equilibrium measure to analyze the distribution of repelling fixed points of a finitely generated rational semigroup, and to derive a sharp bound for the Hausdorff dimension of the Julia set of such a semigroup.
Fast Parallel Algorithm for Prefix Computation in Multi-Mesh Architecture
Authors: Datta Amit , De Mallika , Sinha Bhabani P.
Published: December 2017

A parallel algorithm for prefix computation on [Formula: see text] data elements mapped on a Multi Mesh (MM) network of [Formula: see text] processing elements is presented here. The time required by the proposed algorithm is significantly less than that by any of the existing algorithms for prefix computation on mesh-like architectures due to the specific interconnection pattern used in the MM network. The proposed technique requires [Formula: see text] time for data communication and [Formula: see text] time for computation, when mapped on a MM network constituted by [Formula: see text] meshes, each of size [Formula: see text]. The data communication time in the proposed algorithm is less than the prefix sum algorithm proposed in extended Multi Mesh. To be precise, instead of [Formula: see text] communication time the proposed algorithm requires a data communication time of [Formula: see text] only. Moreover, the proposed parallel algorithm does not need any extra inter block links as used in the extended Multi Mesh.
Pair production processes and flavor in gauge-invariant perturbation theory
Authors: Egger Larissa , Maas Axel , Sondenheimer René
Published: December 2017

Gauge-invariant perturbation theory is an extension of ordinary perturbation theory which describes strictly gauge-invariant states in theories with a Brout–Englert–Higgs effect. Such gauge-invariant states are composite operators which have necessarily only global quantum numbers. As a consequence, flavor is exchanged for custodial quantum numbers in the Standard Model, recreating the fermion spectrum in the process. Here, we study the implications of such a description, possibly also for the generation structure of the Standard Model.

In particular, this implies that scattering processes are essentially bound-state–bound-state interactions, and require a suitable description. We analyze the implications for the pair-production process [Formula: see text] at a linear collider to leading order. We show how ordinary perturbation theory is recovered as the leading contribution. Using a PDF-type language, we also assess the impact of sub-leading contributions. To lowest order, we find that the result is mainly influenced by how large the contribution of the Higgs at large [Formula: see text] is. This gives an interesting, possibly experimentally testable, scenario for the formal field theory underlying the electroweak sector of the Standard Model.
Comparing metric and Palatini approaches to vector Horndeski theory
Authors: Davydov Evgeny
Published: December 2017

We compare cosmologic and spherically symmetric solutions to metric and Palatini versions of vector Horndeski theory. It appears that Palatini formulation of the theory admits more degrees of freedom. Specifically, homogeneous isotropic configuration is effectively bimetric, and static spherically symmetric configuration contains nonmetric connection. In general, the exact solution in metric case coincides with the approximative solution in Palatini case. The Palatini version of the theory appears to be more complicated, but the resulting nonlinearity may be useful: we demonstrate that it allows the specific cosmological solution to pass through singularity, which is not possible in metric approach.