bluuebunny/crossref_metadata_2025_split huggingface dataset:
CYP26B1 declines postnatally in Sertoli cells independently of androgen action in the mouse testis
Authors: Edelsztein Nadia Y. , Kashimada Kenichi , Schteingart Helena F. , Rey Rodolfo A. 
Published: November 2019

AbstractMeiosis begins at puberty and relies on several factors, including androgens and retinoic acid in the mouse testis. CYP26B1 degrades retinoic acid in the testis during prenatal development preventing meiosis initiation. Given the concurrence of meiotic entry and completion of Sertoli cell maturation in response to androgens at puberty in the mouse, we proposed that CYP26B1 is downregulated by androgens in the Sertoli cell during this period. By immunohistochemistry, we showed that CYP26B1 declines in Sertoli cells after birth. However, luciferase reporter assays and quantitative reverse transcription‐polymerase chain reaction performed in the prepubertal mouse Sertoli cell line SMAT1 revealed no changes in Cyp26b1 expression in response to androgen treatment. Furthermore, studies carried out using primary Sertoli cells of 10‐day‐old mice showed no changes in either Cyp26b1 or CYP26B1 expression in response to androgen treatment. In summary, the hereby reported decline in CYP26B1 expression in Sertoli cells towards pubertal onset does not appear to be caused by a direct inhibitory effect of androgens on Sertoli cells in the mouse.
Polymerization Kinetics and Microstructure of Ethylene/1‐Hexene Copolymers Made with Dual Metallocenes
Authors: Saadat Sahar , Soares João B. P. , DesLauriers Paul J. , Fodor Jeff S. 
Published: November 2019

AbstractMathematical models are developed to describe the polymerization of ethylene and 1‐hexene with a constrained geometry catalyst (CGC‐Ti) and with bis(cyclopentadienyl)‐zirconium (IV) dichloride (Cp2ZrCl2). Particle swarm optimization is used to fit these models to homo‐ and copolymerization data. The models are also used to describe copolymerizations with mixtures of CGC‐Ti and Cp2ZrCl2 to make copolymers with inverse short chain branching distribution. Copolymer molecular weight and short chain branch distributions, as well as polymerization rates with the dual metallocene system, are measured to test whether they agreed with model predictions. The results show that the two metallocenes do not interact strongly when used as a mixture to make ethylene/1‐hexene copolymers.
Analytical modeling on consolidation of stiffened deep mixed column‐reinforced soft soil under embankment
Authors: Zhang Zhen , Rao Fengrui , Ye Guanbao 
Published: November 2019

SummaryStiffened deep mixed (SDM) column is a new ground improvement technique to improve soft soil, which can be used to increase bearing capacity, reduce deformation, and enhance stability of soft soil. This technique has been successfully adopted to support the highway and railway embankments over soft soils in China and other countries. However, there have been limited investigations on its consolidation under embankment loading. This paper developed an analytical solution for the consolidation of embankment over soft soil with SDM column in which core pile is equal to or shorter than outer DM column. The consolidation problem was simplified as a consolidation of composite soil considering the load shear effect of core pile. The developed solution was verified by a comparison with the results computed by three‐dimensional (3‐D) finite element analysis. A parametric study based on the derived solution was conducted to investigate influence factors—length of core pile, diameter of core pile, diameter of SDM column, modulus of DM column, and permeability coefficient of DM column—on the consolidation behavior of SDM column‐supported embankment over soft soil. The developed solution was applied to a case history of SDM column‐supported embankment, and a good agreement was found between the predictions and the field measurements.
Order@Cloud: An agnostic meta‐heuristic for VM provisioning, adaptation, and organisation
Authors: Geronimo Guilherme , Uriarte Rafael , Westphall Carlos 
Published: November 2019

SummaryWe propose a flexible meta‐heuristic framework for virtual machine (VM) organisation, provisioning, and adaptation in the cloud domain, based on migration costs and environment constraints. Order@Cloud improves VM placements according to multiple objectives represented by rules, qualifiers, and improvement cost, which can be easily modified and extended. Order@Cloud theoretically guarantees the adoption of a better set of placements, after considering their costs and benefits, by prioritising the worst VM placements. While existing solutions address only specific objectives, our framework is objective‐agnostic and extensible, which enables the adoption and implementation of new policies and priorities. We conduct experiments using a real cloud environment data and discuss the framework's performance, flexibility, and optimality and provide insights on the challenges and benefits of deploying this framework.
Metal Nano Networks by Potential‐Controlled In Situ Assembling of Gold/Silver Nanoparticles
Authors: Köhler J. Michael , Kluitmann Jonas , Knauer Andrea 
Published: November 2019

AbstractInvited for this month's cover picture is the group of Professors Michael Köhler at the Technische Universität Ilmenau. The cover picture shows an overlay of an image of a metal nanoparticle network (blue) and sets of non‐spherical metal nanoparticles of different shapes (yellow). The particles can be used in plasmonic labelling, nanoparticle‐based SERS‐sensing and heterogeneous catalysis. Read the full text of their Full Paper at 10.1002/open.201900231.
Outdoor physical activity, compliance with the physical activity, screen time, and sleep duration recommendations, and excess weight among adolescents
Authors: Sampasa‐Kanyinga Hugues , Colman Ian , Hamilton Hayley A. , Chaput Jean‐Philippe 
Published: November 2019

SummaryBackgroundSpending time outdoor has been identified as an important way to achieve the physical activity required for maintaining and improving health and to lower sedentary time among young children. However, evidence of such relationships in adolescents is particularly limited. This study investigated the relationships between frequency of outdoor physical activity after school, compliance with the physical activity, screen time, and sleep duration recommendations, and overweight/obesity among adolescents.MethodsA total of 10 028 middle and high school students (mean age of 15.2 y) self‐reported the number of weekdays they spent physically active outdoors after school. Physical activity, screen time, sleep duration, height, and weight were self‐reported. Logistic regression models for the total sample and stratified by sex were adjusted for important covariates.ResultsOverall, there was a positive gradient between the number of weekdays spent physically active outdoor after school and compliance with the physical activity (more than or equal to 60 min/day at moderate‐to‐vigorous intensity) and screen time (less than or equal to 2 h/day) recommendations while a negative gradient with overweight/obesity was observed. Significant sex differences were observed in the associations of outdoor physical activity after school with adherence to the sleep duration and physical activity recommendations. For example, outdoor physical activity after school on all 5 days was associated with greater odds of compliance with the sleep duration recommendation among males (OR = 1.53; 95% CI, 1.01‐2.31), but not females (OR = 0.92; 95% CI, 0.65‐1.30).ConclusionsResults suggest that outdoor physical activity after school could be a behavioural target to increase compliance with the physical activity and screen time recommendations and to possibly tackle excess weight among adolescents.
The Unexpected Effects of No Pass, No Drive Policies on High School Education
Authors: Kennedy Kendall J. 
Published: November 2019

AbstractSince 1988, 27 states have introduced No Pass, No Drive laws, which tie a teenager's ability to receive and maintain a driver's license to various school‐related outcomes—most commonly, enrollment and attendance. Enrollment‐Based No Pass, No Drive policies, in 21 states, target both enrollment and attendance, and have negligible effects on dropout rates. However, these policies decrease the Averaged Freshman Graduation Rate (AFGR) by between 1 and 1.7 percentage points. This lower graduation rate stems from students delaying their dropout decision by up to two years. As a result, these students are retained in the ninth and tenth grades, increasing 9th‐grade enrollment by 3.6 percent relative to 8th‐grade enrollment the year prior; this causes an artificial reduction in the graduation rate, rather than a reduction in the true likelihood that a student will graduate. Truancy‐Based No Pass, No Drive policies, in five states, target only attendance—teens that fail to meet a minimum attendance requirement lose their driver's license. However, these policies allow students to drop out of school without facing this penalty. These policies increase the annual dropout rate by between 23 and 34 percent (1 to 1.6 percentage points).
Widening participation and a student “success” assemblage: The materialities and mobilities of university
Authors: Wainwright Emma , Chappell Anne , McHugh Ellen 
Published: November 2019

AbstractThis paper takes an assemblage approach to extend knowledge and understanding of widening participation (WP) in the United Kingdom. We reflect on the identification and experiences of a WP student population—how this population has been marked out, labelled, and considered through policy and intervention, alongside the materialities and mobilities that shape the lived experiences of these students. Using questionnaire findings, narrative interviews, and photo diaries, it draws on a 12‐month study at a London university to explore the factors that have enabled final‐year undergraduate students from a WP background to stay the course and complete their programme of studies. Our arguments are shaped by the geographical and educational literatures on materialities and mobilities. We bring these together to sketch out a student success assemblage comprising wide‐ranging elements that we frame around identity, support, and resources. Assemblage draws attention to the multiplicity of human/non‐human relations that shape student experience and students' capacities for success. Assemblage intersects with university precisely through a focus on experience and, as we suggest, takes on a particular inflexion for students from a WP background. This underpinning ontological basis to studying WP enables us to view the university, student experience, and success as being continually produced and reproduced, and coconstituted between the human and non‐human. Universities should attend to student assemblages to better understand the experiences of and support needed by underrepresented groups in higher education.
Study on properties of wooden capillary electrospray ionization mass spectrometry
Authors: Lin Jiadi , Yan Jing , Xu Qingxuan , Wang Xiwei 
Published: November 2019

RationaleIn view of the unique properties of wooden materials as electrospray emitters, a novel wooden capillary electrospray ionization (WC‐ESI) device was fabricated. The performance of a wooden capillary as an electrospray emitter was investigated by using a wooden capillary instead of the metal emitter of commercial ESI sources.MethodsThe mass spectrometric measurement of baicalein, emodin and myoglobin was carried out by using wooden capillary (WC) and metal capillary (MC) ESI sources. Contrasting analysis of signal intensity between WC and MC electrospray ionization mass spectrometry (ESI‐MS) was implemented at different sample flow rates. The effect of WC‐ESI‐MS and MC‐ESI‐MS was evaluated experimentally with electrospray solutions in different solvent ratios.ResultsGenerally, the signal generated by WC‐ESI‐MS was much stronger than that obtained by MC‐ESI‐MS. In particular, the MS signal in negative ion mode was very strong, which may solve the long‐standing problem of low MS signals in negative ion mode, and fully improve the detection efficiency of ESI‐MS.ConclusionsThe signal intensity produced by WC‐ESI‐MS is significantly higher than that from MC‐ESI‐MS, and polymerization and electrolysis are reduced; therefore, the spectra become simpler. In addition, it is also tolerant to high flow rates and high aqueous phase samples.
Volatile compounds released by Nalophan; implications for selected ion flow tube mass spectrometry and other chemical ionisation mass spectrometry analytical methods
Authors: Brůhová Michalčíková Regina , Dryahina Kseniya , Smith David , Španěl Patrik 
Published: November 2019

RationaleNalophan bags are commonly used to collect breath samples for volatile metabolite analysis. Volatile organic compounds (VOCs) released from the polymer can, however, be mistaken as breath metabolites when analyses are performed by selected ion flow tube mass spectrometry, SIFT‐MS, or techniques that depend on a proper understanding of ion chemistry.MethodsThree analytical techniques were used to analyse the VOCs released into the nitrogen used to expand Nalophan bags, viz. gas chromatography/mass spectrometry (GC/MS), secondary electrospray ionization mass spectrometry (SESI‐MS) and selected ion flow tube mass spectrometry (SIFT‐MS). The most significant VOCs were identified and quantified by SIFT‐MS as a function of storage time, temperature and humidity.ResultsThe consistent results obtained by these three analytical methods identify 1,2‐ethanediol (ethylene glycol) and 2‐methyl‐1,3‐dioxolane as the major VOCs released by the Nalophan. Their concentrations are enhanced by increasing the bag storage temperature and time, reaching 170 parts‐per‐billion by volume (ppbv) for ethylene glycol and 34 ppbv for 2‐methyl‐1,3‐dioxolane in humid nitrogen (absolute humidity of 5%) contained in an 8‐L Nalophan bag stored at 37°C for 160 min.ConclusionsUsing H3O+ reagent ions for SIFT‐MS and SESI‐MS analyses, the following analyte ions (m/z values) are affected by the Nalophan impurities: 45, 63, 81, 89 and 99, which can compromise analyses of acetaldehyde, ethylene glycol, monoterpenes, acetoin, butyric acid, hexanal and heptane.
A new method of ultra‐performance liquid chromatography/tandem mass spectrometry for determination of chlorogenic acid in human plasma and urine
Authors: Han Xiaohong , Li Ning , Liu Shuxia , Yang Sheng , Song Yuanyuan , Shi Yuankai 
Published: November 2019

RationaleChlorogenic acid (CA) is well known for its various biological activities. Here, a clinical study was performed in patients with advanced malignant cancer to explore its therapeutic effects. We aimed to develop a method to quantify CA in human plasma and urine to assist the clinical pharmacokinetic study.MethodsUltra‐performance liquid chromatography (UPLC) coupled with a triple quadruple mass spectrometry was used to separate and detect CA, with puerarin serving as the internal standard.ResultsThe method presents an excellent linearity ranging from 5 to 2000 ng/mL for plasma analysis and 50 to 20 000 ng/mL for urine analysis. Intra‐ and inter‐day precision and accuracy were both less than 15% for plasma and urine.ConclusionsThese results showed that the novel UPLC method was robust and sensitive, and fulfilled the requirements for a clinical pharmacokinetic study of CA in patients with advanced cancer.
Analytical effects on clumped isotope thermometry: Comparison of a common sample set analyzed using multiple instruments, types of standards, and standardization windows
Authors: Defliese William F. , Tripati Aradhna 
Published: November 2019

RationaleCarbonate clumped isotope geothermometry is being increasingly used in multiple disciplines in the geosciences. However, potential interlaboratory issues are arising from different standardization procedures that may contribute to the multiple Δ47‐temperature calibrations reported in the literature. We investigate this issue by comparing a common temperature calibration sample set across three different mass spectrometers, using multiple standardization methods.MethodsThe same temperature calibration sample set was analyzed on three different mass spectrometers. Several standardization methods were utilized, including the use of carbonate versus gas standards, and different types of background correction were applied to the raw data.ResultsAll standardization types applied resulted in statistically indistinguishable Δ47‐temperature slopes, with the exception of standardization calculations that did not correct for background effects. Some instruments and standardizations showed different intercepts relative to each other. The use of carbonate standards improved comparability between different instruments relative to gas standards.ConclusionsOur results show that background effects are the largest factor potentially affecting Δ47 results, and there may be an improvement in interlaboratory precision using carbonate standards. Critically, all techniques used for standardizing Δ47 results converge on a common slope as long as background effects are properly corrected. The use of carbonate standards is recommended as a component of standardization procedures.
Thermal discomfort analysis using UTCI and MEMI (PET and PMV) in outdoor environments: case study of two climates in Iran (Arak & Bandar Abbas)
Authors: Asghari Mehdi , Teimori Gholamheidar , Abbasinia Marzieh , Shakeri Fahimeh , Tajik Reza , Ghannadzadeh Mohammad Javad , Ghalhari Gholamabbas Fallah 
Published: November 2019

AbstractObjectivesThe aim of this study was to analyse the thermal discomfort of outdoor environments in two climates of Iran using physiological equivalent temperature (PET), predicted mean vote (PMV) indices and Universal Thermal Climate Index (UTCI).MethodsIn this study, the meteorological data recorded by the meteorological organisation in a 15‐year period, including temperature, air velocity, cloudiness, relative humidity and water vapour pressure, in two different climates of Iran were surveyed. According to classification of the Köppen, Arak as a representative of a semi‐arid and cold climate and Bandar Abbas as a representative of a hot and dry climate were used to calculate thermal indices. The PMV index was based on the ASHRAE 7‐point thermal sensation scale, and the values of PMV and PET indices were extracted using Rayman1.2 software. The values of the UTCI were calculated using BioKlima 2.6 software.ResultsThe results showed that the maximum and minimum temperatures in two climates were related to July and January, respectively. In Arak, the means of the UTCI, PET and PMV indices were 14.41 ± 11.5, 15.81 ± 1.23 and −0.77 ± 2.15, respectively. In Bandar Abbas as well, the mean of the UTCI, PET and PMV indices were 22.56 ± 9, 22.73 ± 7.7 and 0.73 ± 7.7, respectively. In Arak, there was moderate heat stress to moderate cold stress in this region, whereas in Bandar Abbas, the days had a strong heat stress to low cold stress. There are very strong correlations between the indices used for two different climates.ConclusionThe bioclimatic comfort indices used were able to demonstrate the comfort and discomfort of people during different months of the year in two surveyed climates, and despite trivial differences, they provided relatively uniform representations of climate comfort for surveyed cities. Using thermal comfort indices, high‐risk areas can be identified, and appropriate measures can be adopted to reduce the effects of the changes.
Efficacy of recreational hunters and marksmen for host culling to combat chronic wasting disease in reindeer
Authors: Mysterud Atle , Strand Olav , Rolandsen Christer M. 
Published: November 2019

ABSTRACTMost populations of large mammals in developed countries are managed by human hunting, but there are surprisingly few empirical studies about the benefits and limitations of using recreational hunters to achieve specific management objectives. In particular, the extensive host culling required to markedly reduce population densities to combat some wildlife diseases may conflict with the management aims of landowners and hunters. This is particularly acute in the case of chronic wasting disease (CWD) in cervids, which has now emerged in reindeer (Rangifer tarandus) in Norway. We analyzed the relative efficacy of approximately 1,000 recreational hunters and 30 professional marksmen during the eradication of the entire CWD‐infected population of >2,000 reindeer in Norway. The government changed a series of legislation that would normally limit the efficacy of recreational hunters; these changes were linked to the duration of the hunting season, the specificity and size of the quotas, and spatial access rights. Efforts were taken to reduce both the searching time (hunters were given information on herd whereabouts) and handling time (helicopter aid for transport) of the recreational hunters. We compared 1) recreational hunting under ordinary legislation (up to 2016), 2) recreational hunting with less legislation (2017), and 3) culling by marksmen that were allowed to use both snowmobile and helicopter. Despite all of the changes in legislation, harvest by recreational hunters only increased from 241–316 during 2014–2016 to 582 reindeer in 2017 and was below management targets, while marksmen culled 1,399 reindeer, with a daily average and maximum offtake well above that of the hunters. The hunters shot more animals in the early season and during weekends. Offtake by both the hunters and marksmen were equally negatively affected by fog, which reduced visibility. We discuss the relative merits of using hunters and marksmen for wildlife control in general and limits to how legislation can increase offtake. We highlight the need for more research into how the use of marksmen comes with a cost in terms of social conflict. © 2019 The Authors. Wildlife Society Bulletin published by Wiley Periodicals, Inc. on behalf of The Wildlife Society.