bluuebunny/crossref_metadata_2025_split huggingface dataset:
Chiral separation of helical chromenes with chloromethyl phenylcarbamate polysaccharide‐based stationary phases
Authors: Ianni Federica , Scorzoni Stefania , Gentili Pier Luigi , Di Michele Alessandro , Frigoli Michel , Camaioni Emidio , Ortica Fausto , Sardella Roccaldo 
Published: December 2017

AbstractTwo chloromethyl phenylcarbamate‐based chiral stationary phases, one containing an amylose‐type chiral selector (Lux Amylose 2, from Phenomenex) and the other a cellulose‐type one (Lux Cellulose‐4, from Phenomenex), were successfully used for the chiral resolution of three helical chromenes featuring a helicene‐like structure. The compound bearing a phenyl substituent on the helicene‐like structure was enantioresolved at 25°C with Lux Cellulose‐4 and a n‐hexane/1‐propanol 99:1 v/v eluent. With a n‐hexane/2‐propanol 99.8:0.2 v/v mobile phase, the same column (operated at 35°C) provided the separation of the four isomers of the compound having a hexyl residue on the helicene‐like motif and an additional asymmetric carbon. Lux Amylose‐2 was necessary for the enantioseparation of the compound having the sole hexyl residue on the helical scaffold. For the last compound a n‐hexane/2‐propanol 99.8:0.2 v/v eluent was used, and the column temperature was fixed at 5°C. The enantiomer elution order was appraised by using electronic circular dichroism and theoretical calculations. Notably, different thermodynamics of retention and enantioseparation were observed for molecules with pronounced structural similarity, that is, the enantiomer pairs of the compound containing the additional asymmetric carbon atom. Indeed, both entropically and enthalpically controlled adsorption and separation processes were observed.
Direct HPLC separation of carnosine enantiomers with two chiral stationary phases based on penicillamine and teicoplanin derivatives
Authors: Fumagalli Laura , Pucciarini Lucia , Regazzoni Luca , Gilardoni Ettore , Carini Marina , Vistoli Giulio , Aldini Giancarlo , Sardella Roccardo 
Published: December 2017

AbstractCarnosine is present in high concentrations in specific human tissues such as the skeletal muscle, and among its biological functions, the remarkable scavenging activity toward reactive carbonyl species is noteworthy. Although the two enantiomers show almost identical scavenging reactivity toward reactive carbonyl species, only d‐carnosine is poorly adsorbed at the gastrointestinal level and is stable in human plasma. Direct methods for the enantioselective analysis of carnosine are still missing even though they could find more effective applications in the analysis of complex matrices. In the present study, the use of two different chiral stationary phases is presented. A chiral ligand‐exchange chromatography stationary phase based on N,S‐dioctyl‐d‐penicillamine resulted in the direct enantioseparation of carnosine. Indeed, running the analysis at 25°C and 1.0 mL/min with a 1.5 mM copper(II) sulfate concentration allowed us to obtain separation and resolution factors of 3.37 and 12.34, respectively. However, the use of a copper(II)‐containing eluent renders it hardly compatible with mass spectrometry detectors. With the teicoplanin‐based stationary phase, a mass spectrometry compatible method was successfully developed. Indeed, a water/methanol 60:40 v/v pH 3.1 eluent flowed at 1.0 mL/min and with a 25°C column temperature produced separation and resolution factors of 2.60 and 4.16, respectively.
Effects of land preparation and plantings of vegetation on soil moisture in a hilly loess catchment in China
Authors: Tianjiao Feng , Wei Wei , Liding Chen , Keesstra Saskia D. , Yang Yu 
Published: December 2017

AbstractIn the dryland and degraded regions, soil moisture is the primary factor determining ecological restoration. Proper land preparations and vegetation restoration can improve soil moisture and benefit land restoration. Identifying their effects on soil moisture is thus essential for developing suitable management strategies. In this study, four typical land preparation techniques (level ditches, fish‐scale pits, zig terraces, and level benches) and non‐native vegetation types (Prunus armeniaca, Platycladus orientalis, Pinus tabulaeformis, and Caragana microphylla) were planted on a semiarid loess hilly catchment, China. Soil moisture was monitored by a time‐domain reflectometer, and its spatial–temporal variations were analyzed during the 2014–2015 growing seasons. The following results were captured. (a) Soil moisture was highest for the combination of P. orientalis and fish‐scale pits (P. orientalis/fish‐scale pits, 10.37%), followed by P. armeniaca/level ditches (10.23%), P. orientalis/zig terraces (9.67%), C. microphylla/level benches (8.62%), P. tabulaeformis/fish‐scale pits (8.05%), and P. tabulaeformis/zig terraces (7.72%). (b) Fish‐scale pits offered a better rainwater‐harvesting capacity during the rainy months, whereas zig terraces had a higher water retention capacity under extremely dry conditions (as indicated by the temporal soil moisture variation and soil water retention curves). (c) P. tabulaeformis consumed more water than other vegetation types (26.7% lower than that of P. orientalis). (d) Soil moisture in shallower layers (0–80 cm) was more affected by land preparations and was more effected by vegetation types in deeper soil layers (80–180 cm). We thus suggest that fish‐scale pits may be a better choice in wetter regions whereas zig terraces and P. orientalis are more suitable in the driest parts of the Loess Plateau to restore the fragile ecosystems.
Placenta microstructure and microcirculation imaging with diffusion MRI
Authors: Slator Paddy J. , Hutter Jana , McCabe Laura , Gomes Ana Dos Santos , Price Anthony N. , Panagiotaki Eleftheria , Rutherford Mary A. , Hajnal Joseph V. , Alexander Daniel C. 
Published: December 2017

PurposeTo assess which microstructural models best explain the diffusion‐weighted MRI signal in the human placenta.MethodsThe placentas of nine healthy pregnant subjects were scanned with a multishell, multidirectional diffusion protocol at 3T. A range of multicompartment biophysical models were fit to the data, and ranked using the Bayesian information criterion.ResultsAnisotropic extensions to the intravoxel incoherent motion model, which consider the effect of coherent orientation in both microvascular structure and tissue microstructure, consistently had the lowest Bayesian information criterion values. Model parameter maps and model selection results were consistent with the physiology of the placenta and surrounding tissue.ConclusionAnisotropic intravoxel incoherent motion models explain the placental diffusion signal better than apparent diffusion coefficient, intravoxel incoherent motion, and diffusion tensor models, in information theoretic terms, when using this protocol. Future work will aim to determine if model‐derived parameters are sensitive to placental pathologies associated with disorders, such as fetal growth restriction and early‐onset pre‐eclampsia. Magn Reson Med 80:756–766, 2018. © 2017 The Authors Magnetic Resonance in Medicine published by Wiley Periodicals, Inc. on behalf of International Society for Magnetic Resonance in Medicine. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
Effects of analgesics on bone mineral density: A longitudinal analysis of the prospective SWAN cohort with three‐group matching weights
Authors: Yoshida Kazuki , Yu Zhi , Greendale Gail A. , Ruppert Kristine , Lian Yinjuan , Tedeschi Sara K. , Lin Tzu‐Chieh , Haneuse Sebastien , Glynn Robert J. , Hernández‐Díaz Sonia , Solomon Daniel H. 
Published: December 2017

AbstractPurposeTo examine the effects of analgesics on bone mineral density (BMD), which have not been examined in a longitudinal study with multiple measurements.MethodsWe investigated changes in BMD associated with new use of analgesics in a prospective longitudinal cohort of mid‐life women. BMD and medication use were measured annually. We compared BMD among new users of acetaminophen, NSAIDs, and opioids. Adjustment for baseline covariates was conducted through propensity score matching weights. On‐treatment analysis was conducted with inverse probability of censoring weights. Analysis based on the initial treatment group was also conducted to provide insights into selection bias. Repeated BMD measurements were examined with generalized estimating equations.ResultsWe identified 71 acetaminophen new users, 659 NSAID new users, and 84 opioid new users among 2365 participants. In the on‐treatment analysis, the opioid group in comparison to the acetaminophen group had an additional average BMD decline of −0.06% [−1.24, 1.11] per year in the spine and −0.45% [−1.51, 0.61] per year in the femoral neck. BMD mean trajectories over time suggested a fifth‐year decline in the opioid persistent users compared with other 2 groups. In the initial treatment group analysis, all 3 groups showed similar trajectories.ConclusionThe BMD decline over time was similar among the 3 groups. However, 5 years of continuous opioid use may be associated with a greater BMD decline than 5 years on other analgesics. Further studies examining the relationship between very long‐term persistent opioid use and BMD are warranted.
The Product Environmental Footprint (PEF) of photovoltaic modules—Lessons learned from the environmental footprint pilot phase on the way to a single market for green products in the European Union
Authors: Wade Andreas , Stolz Philippe , Frischknecht Rolf , Heath Garvin , Sinha Parikhit 
Published: December 2017

AbstractShaping and channeling the transformation of the global energy system require an understanding of the life cycle environmental impacts of available technology options. With photovoltaic electricity generation expected to be the largest, least cost, and most relevant source of energy globally by mid‐century, the environmental and resource implications of this technology should be made accessible to a variety of societal, political, and scientific stakeholders. The Product Environmental Footprint Guide provides a methodology for assessing the environmental impacts of PV technologies based on life cycle assessment. The establishment of an inclusive multi‐stakeholder process with multiple checkpoints, ensuring scientific soundness, societal and political acceptance and methodological quality, is portrayed in this paper and can serve as a model for driving a single market for green products in the EU.
Juvenile social experience and differential age‐related changes in the dendritic morphologies of subareas of the prefrontal cortex in rats
Authors: Himmler Brett T. , Mychasiuk Richelle , Nakahashi Ayuno , Himmler Stephanie M. , Pellis Sergio M. , Kolb Bryan 
Published: December 2017

AbstractJuvenile social interactions have been shown to influence the dendritic complexity of neurons in the prefrontal cortex (PFC). In particular, social play induces pruning of the cells in the medial prefrontal cortex (mPFC), whereas interacting with multiple partners, whether those interactions involve play or not, increases the complexity of cells in the orbital frontal cortex (OFC). Previous studies suggest that these changes differ in their stability during adulthood. In the present study, rats were reared in groups of either four (quads) or two (pairs) and the brains of the rats from each rearing condition were then harvested at 60 days (i.e., shortly after sexual maturity) and 100 days (i.e., fully adult). The rats housed with multiple partners had more complex neurons of the OFC at 60 days and this complexity declined to a comparable level to that of pair housed rats by 100 days. In contrast, the play‐induced changes of the mPFC remained similar at both ages. These findings suggest that the changes in the PFC induced by different social experiences in the juvenile period differ in how long they are maintained in adulthood. Differences in the functions regulated by the OFC and the mPFC are considered with regard to these differences in the stability of juvenile‐induced neural changes.
Theoretical investigations on load‐bearing capacity of RC flat‐plate framed structures subject to middle column loss
Authors: Zhang Jing‐Zhou , Li Guo‐Qiang , Wang Yan‐Bo , Jiang Jian 
Published: December 2017

SummaryThis paper presents theoretical studies on load‐bearing capacity of reinforced concrete flat‐plate framed structures. The existing methods for determining load‐bearing capacity of simply supported slabs are first reviewed, and their limitations are presented. An energy‐based refined method is then proposed to enhance the accuracy of the existing methods by considering the contributions to internal energy dissipation due to the extension of reinforcing bars along yield lines, the additional resultant bending moment from membrane forces, and the sectional bending moment along yield lines of slabs. The refined method for simply supported slabs is extended for fixed supported slabs, and thus, the load‐bearing capacity of reinforced concrete flat‐plate structures subject to a middle column loss is analytically determined. The performance of the proposed method is validated against test results and also verified against finite element analyses. Parametric studies are conducted to investigate the effect of reinforcement ratio, slab thickness and aspect ratio on the stiffness, and yield‐line resistance of structures. It is found that for the fixed supported slabs, it is reasonable to assume negative yield lines along the slab edges to consider the effect of obvious concrete crushing along the edge. Square slabs have higher ultimate loads than rectangular slabs, due to a longer horizontal yield line in the middle in the rectangular slab, which has detrimental effect on the sectional ultimate bending moment. The numerical results show that the reinforcement ratio has little effect on the initial bending stiffness and yield‐line resistance of slabs for a given slab thickness and aspect ratio. The initial stiffness and yield‐line resistance increase as the slab thickness increases. For the same reinforcement ratio and slab thickness, a larger aspect ratio leads to a lower initial bending stiffness, yield‐line resistance, and stiffness in tensile membrane action stage, due to a longer yield line along which tensile membrane forces have a detrimental effect on the sectional bending moment.
Can a Good Person be a Good Trader? An Ethical Defense of Financial Trading
Authors: Rocchi Marta , Thunder David 
Published: December 2017

AbstractIn a 2015 article entitled “The Irrelevance of Ethics,” MacIntyre argues that acquiring the moral virtues would undermine someone’s capacity to be a good trader in the financial system and, conversely, that a proper training in the virtues of good trading directly militates against the acquisition of the moral virtues. In this paper, we reconsider MacIntyre’s rather damning indictment of financial trading, arguing that his negative assessment is overstated. The financial system is in fact more internally diverse and dynamic, and more reformable, than suggested by MacIntyre’s treatment. The challenge at the heart of MacIntyre’s claims can be crystallized in the question, “under which conditions, if any, can a person be an effective trader and simultaneously live a worthy human life?” We conclude that there are realistic possibilities of integrity and growth in moral virtue for those who work in the financial sector, at least for those operating in a work environment minimally permissive toward virtue, provided they possess characters of integrity and genuine aptitude for the skills and attitudes required in their professional tasks.
Use of the Radiocarbon Activity Deficit in Vegetation as a Sensor of CO2 Soil Degassing: Example from La Solfatara (Naples, Southern Italy)
Authors: Lefevre Jean-Claude , Gillot Pierre-Yves , Cardellini Carlo , Gresse Marceau , Lesage Louis , Chiodini Giovani , Oberlin Christine 
Published: December 2017

AbstractSoil CO2 flux measurement is a key method that can be used to monitor the hazards in an active volcanic area. In order to determine accurately the variations of the CO2 soil emission we propose an approach based on the radiocarbon (14C) deficiency recorded in the plants grown in and around the Solfatara (Naples, Italy). We twice sampled selected poaceae plants in 17 defined sites around the Solfatara volcano. 14C measurements by liquid scintillation counting (LSC) were achieved on the grass samples. The 14C deficiency determined in the sampled plants, compared to the atmosphere 14C activity, ranged from 6.6 to 51.6%. We then compared the proportion of magmatic CO2 inferred to the instantaneous measurements of CO2 fluxes from soil performed by the accumulation chamber CO2 degassing measurement at the moment of the sampling at each site. The results show a clear correlation (r=0.88) between soil CO2 fluxes and 14C activity. The determination of the plants 14C deficiency provides an estimate of the CO2 rate within a few square meters, integrating CO2 soil degassing variations and meteorological incidences over a few months. It can therefore become an efficient bio-sensor and can be used as a proxy to cartography of the soil CO2 and to determine its variations through time
The conservation costs and economic benefits of using biodiversity offsets to meet international targets for protected area expansion
Authors: Buschke Falko T. , Brownlie Susie , Manuel Jeff 
Published: December 2017

AbstractAichi Biodiversity Target 11 under the Convention on Biological Diversity sets out to conserve at least 17% of terrestrial area by 2020. However, few countries are on track to meet this target and it is uncertain whether developing countries have allocated sufficient resources to expand their protected areas. Biodiversity offsets could resolve this conservation shortfall if developers who affect biodiversity negatively at one locality are made responsible for its protection elsewhere. Here we simulate the use of biodiversity offsetting to expand protected area coverage in South Africa's grassland biome. South Africa's biodiversity offsets policy has been designed specifically to compensate for the residual loss of biodiversity caused by development, by establishing and managing protected areas within the same ecosystem type. We show that it is possible to meet protected area targets using only offsets, while facilitating economic development. However, doing so could slash the current extent of intact habitat by half. These losses could be reduced considerably should the gains in protected areas through offsetting supplement rather than supplant existing government commitments to protected area expansion. Moreover, supplementing existing government commitments would result in comparatively small reductions in potential economic gains, because the marginal economic benefit of transforming habitat decreases as more intact habitat is lost. Therefore, the intended role of biodiversity offsetting in achieving a country's protected area target should be made explicit to fully understand the associated trade-offs between conservation and economic development.
RECONSTRUCCIÓN DE SERIES DE VALOR DEL COMERCIO EXTERIOR DE HONDURAS. 1880–1930
Authors: Díaz Rafael Ángel Ledezma 
Published: December 2017

AbstractThis article presents, for the first time, a continuous series of value of Honduran exports and imports for the period 1880-1930, extending the series previously available from Notten (2012). The new series were constructed based on the official statistics of the main trading partners of Honduras (United States, Great Britain, Germany and France) corrected from Honduran and complementary sources. The correction criteria applied are based on the results of a previous reliability validation exercise. The data obtained allow to delimit a new chronology of the foreign trade of Honduras where the “export age” began before the banana export boom that took place between 1903 and 1930.
Formation of electron holes in the long-time evolution of the bump-on-tail instability
Authors: Shoucri Magdi 
Published: December 2017

AbstractAn Eulerian Vlasov code is applied for the numerical solution of the one-dimensional Vlasov–Poisson system of equations for electrons, and with ions forming an immobile background. We study the non-linear evolution of the bump-on-tail instability in the case when the system length L is greater than the wavelength λ of the unstable mode, with a beam density of 10% of the total density, nb = 0.1. We follow the growth and the saturation of an initially unstable wave perturbation, and the formation of a traveling Bernstein–Greene–Kruskal (BGK) mode, which evolves out of the instability. This first stage is followed by sidebands growing from round-off errors which develop and disrupt the BGK equilibrium. In the excited spectrum, mode coupling is mediated by the oscillating resonant particles and results in the electric energy of the system flowing to the longest wavelengths (inverse cascade), and reaching in the asymptotic state a steady state with constant amplitude oscillation modulated by the persistent oscillation of the trapped particles. Coherent phase-space electron holes are formed, which are localized phase-space regions of reduced density on trapped electron orbits, where the electron density is lower than the surrounding plasma electron density. The distribution function evolves to a shape with stationary inflection points of zero slope, at the phase velocities of the excited waves. The longest wavelengths show oscillations at frequencies below the plasma frequency, with phase velocities higher than that of the injected beam, which can accelerate electrons to energies in excess of the initial beam energy. The present work makes a connection between the formation of electron holes, the existence of inflection points of zero slopes in the electron distribution function at the phase velocities of the dominant waves, and at frequencies below the plasma frequency. A fine resolution grid is used in the Eulerian Vlasov code in the phase space and time to allow an accurate calculation of the time history of the system and of the dynamic and oscillation of the trapped particles in the low-density regions of the phase space, and of those particles at the separatrix regions of the vortex structures which evolve periodically between trapping and untrapping states and which can only be accurately studied using a fine-resolution phase-space grid.
Sequences of maladaptation: Preadolescent self-regulation, adolescent negative social interactions, and young adult psychopathology
Authors: Laceulle Odilia M. , Veenstra René , Vollebergh Wilma A. M. , Ormel Johan 
Published: December 2017

AbstractThis study aims to test whether adolescent negative social interactions mediate the relation between early adolescent self-regulatory capacities and young adult psychopathology, using a fully prospective mediation model. Data were derived from the Tracking Adolescents’ Individual Lives Survey, a large population cohort of Dutch adolescents (n = 962). At age 11, three indicators of self-regulation were assessed: low frustration, high effortful control, and high response inhibition. Negative social interactions between ages 11 and 22 were captured twice using the Event History Calendar. Psychopathology (i.e., internalizing and externalizing problems) was assessed at ages 11 and 22. Findings indicate that adolescents’ frustration and effortful control but not response inhibition assessed at age 11 are related to both internalizing and externalizing problems at age 22, after controlling for psychopathology at age 11, sex, and socioeconomic status. These associations were partly (about 22%) mediated by the negative social interactions adolescents experienced. Effect sizes were all modest. This study shows that self-regulation is related to subsequent psychopathology in part through its effect on negative social interactions, providing evidence for sequences of self-regulatory capacities, life experiences, and developmental outcomes.