bluuebunny/crossref_metadata_2025_split huggingface dataset:
Climate‐related trends of actual evapotranspiration over the Tibetan Plateau (1961–2010)
Authors: Zhang Tangtang , Gebremichael Mekonnen , Meng Xianhong , Wen Jun , Iqbal Mudassar , Jia Dongyu , Yu Ye , Li Zhenchao 
Published: December 2017

ABSTRACTActual evapotranspiration (ETa) is an important component of the hydrologic cycle. In this study, ETa on the Tibetan Plateau (TP) is calculated using the advection‐aridity model (AA model) with data from 86 meteorological stations during the period from 1961 to 2010. Results show that the mean annual ETa over the TP was 543 mm and range from 147 to 687 mm, with higher values in the southern part and lower values in the northern part of the TP. During 1961–2010, annual and seasonal mean ETa show statistically increasing trend at most all stations. Annual ETa in area‐averaged over the TP changed +1.01 mm year−1. Among the four seasons, the changes were most pronounced in March, April, May (MAM) and June, July, August (JJA). ETa variation is significantly and positively correlated with a drought index, defined as the difference between precipitation (P) and potential evapotranspiration (ETp), i.e. P − ETp, showing that the ETa increases over the TP tend to be affected by an increasing soil water supply associated with global warming, such as the retreat of permafrost, increase in P, and decline of ETp.
Preclinical models for orthopedic research and bone tissue engineering
Authors: Schindeler Aaron , Mills Rebecca J. , Bobyn Justin D. , Little David G. 
Published: December 2017

ABSTRACTIn this review, we broadly define and discuss the preclinical rodent models that are used for orthopedics and bone tissue engineering. These range from implantation models typically used for biocompatibility testing and high‐throughput drug screening, through to fracture and critical defect models used to model bone healing and severe orthopedic injuries. As well as highlighting the key methods papers describing these techniques, we provide additional commentary based on our substantive practical experience with animal surgery and in vivo experimental design. This review also briefly touches upon the descriptive and functional outcome measures and power calculations that are necessary for an informative study. Obtaining informative and relevant research outcomes can be very dependent on the model used, and we hope this evaluation of common models will serve as a primer for new researchers looking to undertake preclinical bone studies. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:832–840, 2018.
Risk of peritoneal metastases in patients who had negative peritoneal staging and received therapy for localized gastric adenocarcinoma
Authors: Mizrak Kaya Dilsa , Nogueras‐González Graciela M. , Harada Kazuto , Amlashi Fatemeh G. , Roy‐Chowdhuri Sinchita , Estrella Jeannelyn S. , Das Prajnan , Lee Jeffrey H. , Weston Brian , Bhutani Manoop S. , Matamoros Aurelio , Thomas Irene , Lin Quan , Badgwell Brian D. , Ajani Jaffer A. 
Published: December 2017

BackgroundPositive peritoneal cytology (+PCyt) or gross carcinomatosis (GPC) carries a poor prognosis. Laparoscopic staging to detect +PCyt/GPC is recommended for all ≥T1b gastric adenocarcinoma (GAC). The natural history of patients with GAC who have baseline −PCyt and then undergo multimodality therapy is not well documented, particularly for the risk of subsequent GPC.MethodsWe identified 238 GAC patients with baseline −PCyt who were followed for the development of peritoneal carcinomatosis (PC). Standard statistical methods were employed.ResultsOf 238 patients, 192 had attempted surgery after preoperative therapy. Of these, 13 patients (6.8%) had GPC and one had liver metastases, thus surgery was aborted. We followed 164 patients who had an R0 resection. The median follow‐up duration was 3.4 (range, 0.6‐18) years. The rate of PC was 13.4%, (22/164 patients) and the median time to PC was 15.6 months. Female gender was associated with PC on multivariate analysis. The 5‐year OS rate for patients without subsequent PC was 75%.Conclusion Even with baseline −Cyt, ∼25% of patients develop PC following multimodality therapy. Patients who do not develop PC have an excellent OS rate. Further research is warranted to detect PC at baseline by the use of biomarkers.
Integrated population models facilitate ecological understanding and improved management decisions
Authors: Arnold Todd W. , Clark Robert G. , Koons David N. , Schaub Michael 
Published: December 2017

ABSTRACTIntegrated population models (IPMs) represent a formal statistical methodology for combining multiple data sets such as population counts, band recoveries, and fecundity estimates into a single unified analysis with dual objectives: better estimating population size, trajectory, and vital rates; and formally describing the ecological processes that generated these patterns. Although IPMs have been used in population ecology and fisheries management, their use in wildlife management has been limited. Data sets available for North American waterfowl are unprecedented in terms of time span (>60 years) and geographic coverage, and are especially well‐suited for development of IPMs that could improve the understanding of population ecology and help guide future harvest and habitat management decisions. In this overview, we illustrate 3 potential benefits of IPMs: integration of multiple data sources (i.e., population counts, mark‐recapture data, and fecundity estimates), increased precision of parameter estimates, and ability to estimate missing demographic parameters by reanalyzing results from a historical study of canvasbacks (Aythya valisineria). Drawing from our own published and unpublished work, we demonstrate how IPMs could be used to identify the critical vital rates that have had the greatest influence on population change in lesser scaup (Aythya affinis), evaluate potential mechanisms of harvest compensation for American black ducks (Anas rubripes), or prioritize the most appropriate places to conduct habitat management to benefit northern pintails (Anas acuta). Integrated population models provide a powerful platform for evaluating alternative hypotheses about population regulation and they have potential to advance the understanding of wildlife ecology and help managers make ecologically based decisions. © 2017 The Wildlife Society.
Association of palatine tonsil size and obstructive sleep apnea in adults
Authors: Jara Sebastian M. , Weaver Edward M. 
Published: December 2017

ObjectiveThe relationship between palatine tonsil (PT) size and obstructive sleep apnea (OSA) has not been well established in adults. The purpose of this study was to test the association between PT grade, PT volume, and OSA severity in U.S. adult patients.Study DesignCross‐sectional study of all patients (age ≥ 18 years) who underwent pharyngeal surgery for OSA that included palatine tonsillectomy with tonsil volume measurement from January 2011 to June 2016.MethodsMedical records were reviewed for PT grade (measured on clinical exam by the Brodsky tonsil grading scale), PT volume (measured intraoperatively by water displacement), and apnea–hypopnea index (AHI). Associations were evaluated with multivariate linear regression adjusting for age, sex, body mass index (BMI), smoking status, lingual tonsil volume (AHI models only), and multilevel surgery aside from lingual tonsillectomy (PT volume vs. AHI model only).ResultsThe cohort (N = 83) was middle‐aged (mean age 43 ± 12 years), predominantly male (61%), obese (mean BMI 33 ± 7 kg/m2), and had severe OSA (mean AHI 32 ± 28). After adjustment for confounders, PT grade was strongly associated with PT volume (beta = 1.8, 95% confidence interval [CI]: [1.0, 2.6], P < 0.001) and with AHI (beta = 13.5, 95% CI: [3.5, 23.6], P = 0.01); PT volume was not associated with AHI (beta = −0.2, 95% CI: [−2.2, 1.9], P = 0.89).ConclusionIn contrast to past studies, subjective PT grade (vs. objective PT volume) was more strongly associated with AHI. These data suggest the space that the tonsils occupy within the oropharyngeal airway, instead of their actual measured volume, may be more predictive of OSA severity in a cohort of U.S. adult patients.Level of Evidence2c. Laryngoscope, 128:1002–1006, 2018
Biogeochemical characteristics and fluxes of suspended particulate organic matter in response to low‐tide rainfall
Authors: Chen Si , Torres Raymond 
Published: December 2017

AbstractWe evaluated the effects of low‐tide rainfall on salt marsh particulate organic carbon (POC) cycling. Suspended sediment samples from intertidal creeks were collected during rain and no‐rain conditions. Bulk (carbon, nitrogen) and molecular (e.g., lignin) compositions of organic constituents in particulates were analyzed. Temporal patterns of suspended sediment concentration mimic fluctuations in rainfall intensity, but all POC constituents do not necessarily follow these patterns. For example, particulate organic matter concentrations in water column covaried with rain intensity yet organic matter (OM) contents in the particles showed trivial correlations with rain. In general, rainfall effects raised the suspended sediment and organic constituent concentrations in the water column by up to three orders of magnitude. Multivariate statistical analysis revealed that the rainfall‐entrained particulates were compositionally distinct from calm weather suspended particulates, from salt marsh surface sediment, and from creek bank surface sediment. Rainfall‐entrained particulates are depleted in bulk organic carbon and phytoplankton‐derived OM but enriched in lignin phenols. These observations indicate that rainfall‐runoff processes preferentially mobilize POC derived from Spartina alterniflora from marsh platforms and effectively transport these materials to intertidal creeks following low‐tide rainfall events. Moreover, average net transport rates by rainfall are 0.020 ± 0.002 gPOC m−2 mmRain−1, and this POC turnover rate amounts to ∼ 19% of the annual POC export from estuary to ocean. Therefore, estuarine outwelling estimates typically made under calm weather conditions represent minimum levels of POC export. Hence, low‐tide rainfall can be expected to substantially enhance the delivery of marsh‐derived POC to the coastal ocean.
An evaluation of the WRF Mei‐yu rainfall forecasts in Taiwan, 2008–2010: differences in elevation and sub‐regions
Authors: Paul Sahana , Wang Chung‐Chieh , Chien Fang‐Ching , Lee Dong‐In 
Published: December 2017

ABSTRACTThis study explores differences in the performance of the Mei‐yu quantitative precipitation forecast (QPF) in Taiwan by use of the Weather Research and Forecasting (WRF) model in continuation of an earlier study, with particular detailed focus on those among three elevation ranges and four sub‐regions at different stages of the season and within the diurnal cycle. Against data from about 400 rain gauges, both subjective and objective verifications are performed to complement each other. The Mei‐yu QPF's skill is shown to vary with evaluation periods (every half‐month) within the season, with elevation (categorized as plain (0–250 m), slope (0.25–1 km) and mountain (>1 km) areas), and also with sub‐region (northern, central, southern and eastern Taiwan). The diurnal cycle of rainfall produced by the model is strong over the mountains, but too weak over the plains. Overall, the model exhibits the highest skill in southern and central Taiwan, where more rain occurs due to forced uplift of the prevailing southwesterly flow over the windward slopes (mainly during the first half of June). In general, the more rainfall there is, the better the model performs (with higher skill) during the Mei‐yu season.
(‐)‐Epicatechin and the Colonic 2,3‐Dihydroxybenzoic Acid Metabolite Regulate Glucose Uptake, Glucose Production, and Improve Insulin Signaling in Renal NRK‐52E Cells
Authors: Álvarez‐Cilleros David , Martín María Ángeles , Ramos Sonia 
Published: December 2017

Scope(‐)‐Epicatechin (EC) and main colonic phenolic acids derived from flavonoid intake, such as 2,3‐dihydroxybenzoic acid (DHBA), 3,4‐dihydroxyphenylacetic acid (DHPAA), 3‐hydroxyphenylpropionic acid (HPPA), and vanillic acid (VA), have been suggested to exert beneficial effects in diabetes, although the mechanism for their actions remains unknown. In this study, the modulation of glucose homeostasis and insulin signaling by the mentioned compounds on renal proximal tubular NRK‐52E cells is investigated.Methods and resultsLevels of the glucose transporters SGLT‐2 and GLUT‐2, as well as glucose uptake, glucose production, and key proteins of the insulin pathways, namely insulin receptor (IR), insulin receptor substrate‐1 (IRS‐1), and PI3K/AKT pathway are analyzed. EC (5‐20 μm) and DHBA (20 μm) reduced both renal glucose uptake and production. Interestingly, EC and DHBA did not modify the levels of SGLT‐2 and GLUT‐2, and modulated the expression of phosphoenolpyruvate carboxykinase via AKT leading to a diminished glucose production. EC and DHBA also enhanced the tyrosine phosphorylation and total IR and IRS‐1 levels, and activated the PI3K/AKT pathway in NRK‐52E cells.ConclusionEC and DHBA regulate the renal glucose homeostasis by modulating both glucose uptake and production, and strengthen the insulin signaling by activating key proteins of that pathway in NRK‐52E cells.
Vitamin D Does Not Play a Functional Role in Adipose Tissue Development in Rodent Models
Authors: Schutkowski Alexandra , Max Daniela , Bönn Markus , Brandsch Corinna , Grundmann Sarah M. , Hirche Frank , Staege Martin S. , Stangl Gabriele I. 
Published: December 2017

ScopeSeveral studies have proposed a role of vitamin D in adipogenesis. Here, we sought to study the impact of the vitamin D receptor (Vdr) on adipocyte size in young and old mice and the effect of maternal vitamin D deficiency on fetal adipogenesis.Methods and resultsHistological analysis of adipose tissues shows that Vdr knockout (KO) mice have smaller adipocytes than wild‐type (WT) mice. Next, we compare young and old Vdr‐KO and WT mice and find no differences in adipocyte sizes between weaned Vdr‐KO and WT mice. However, 1‐year‐old Vdr‐KO mice, suffering from alopecia, have smaller‐sized adipocytes than WT mice, although they consume more food. To elucidate whether vitamin D can directly impact adipocyte development at a critical stage of adipogenesis, we feed rat dams a vitamin D deficient (0 IU kg−1) or vitamin D adequate (1000 IU kg−1) diet. Neither DNA microarray analysis of the adipose tissues of the newborn rats nor the adipocyte sizes of 21‐day‐old offspring show significant differences between the two groups.ConclusionData indicate that vitamin D does not play a fundamental role in adipogenesis because vitamin D does not affect fetal adipogenesis. Moreover, the smaller adipocytes observed in adult Vdr‐KO mice are presumably caused by an increased energy expenditure due to alopecia.
Directional scatter imaging for the stereoscopic tracking of fiducial markers in a single kV exposure
Authors: Garnica‐Garza Héctor Mauricio 
Published: December 2017

PurposeTo demonstrate, via Monte Carlo simulation, that an image obtained from the patient‐generated scattered radiation forced to impinge on the detector from a known direction by means of parallel‐focused grids, can be used to complement the information conveyed by the primary image, such that accurate stereoscopic three‐dimensional localization of fiducial markers can be achieved in a single kV x‐ray exposure.MethodsA voxelized Zubal phantom was used to model the process of fiducial marker localization. The markers were represented as made of gold and cylindrical in shape with dimensions of 5 mm in length and 1 mm in diameter. Three such markers were placed in the Zubal phantom at the prostate level. Two gantry‐mounted image acquisition geometries were modeled: a single kV imaging system and a dual kV–MV imaging system. The detector was modeled as a 30 cm × 40 cm Gd2O2S screen with a thickness of 0.2 cm and a resolution of 768 × 1024 pixels. The PENELOPE Monte Carlo code was used to calculate the absorbed dose in this detector imparted by the transmitted primary and directional scatter radiation. A grayscale conversion was then applied to obtain an image from which the positions of the markers were determined. Two parallel‐focused grid geometries were modeled, one based on the standard lead‐carbon fiber grids and a proposed modification using tungsten as the shielding material. Absorbed dose in the patient model was also calculated.ResultsIt is shown that the combination of primary and directional scatter images provides the means for an accurate stereoscopic fiducial marker 3D localization in a single x‐ray exposure, provided the antiscatter grids are made thick enough to allow radiation traveling only in a particular direction to reach the detector. For the proposed tungsten grid and the x‐ray spectrum used in this work, grid ratios of 20 and thickness of 0.2 cm, provide the necessary shielding while for the standard lead grids, a ratio of at least 166 and a thickness of 2 cm are needed to obtain discernible directional scatter images.ConclusionsWe have shown that it is in principle possible to determine the 3D position of fiducial markers in a single exposure by making use of the radiation scattered by the patient to form an image that complements the information obtained with the primary beam. The method here proposed requires minimal modification of existing clinical hardware.
High dose‐per‐pulse electron beam dosimetry: Commissioning of the Oriatron eRT6 prototype linear accelerator for preclinical use
Authors: Jaccard Maud , Durán Maria Teresa , Petersson Kristoffer , Germond Jean‐François , Liger Philippe , Vozenin Marie‐Catherine , Bourhis Jean , Bochud François , Bailat Claude 
Published: December 2017

PurposeThe Oriatron eRT6 is an experimental high dose‐per‐pulse linear accelerator (linac) which was designed to deliver an electron beam with variable dose‐rates, ranging from a few Gy/min up to hundreds of Gy/s. It was built to study the radiobiological effects of high dose‐per‐pulse/dose‐rate electron beam irradiation, in the context of preclinical and cognitive studies. In this work, we report on the commissioning and beam monitoring of the Oriatron eRT6 prototype linac.Materials and MethodsThe beam was characterized in different steps. The output stability was studied by performing repeated measurements over a period of 20 months. The relative output variations caused by changing beam parameters, such as the temporal electron pulse width, the pulse repetition frequency and the pulse amplitude were also analyzed. Finally, depth dose curves and field sizes were measured for two different beam settings, resulting in one beam with a conventional radiotherapy dose‐rate and one with a much higher dose‐rate. Measurements were performed with Gafchromic EBT3 films and with a PTW Advanced Markus ionization chamber. In addition, we developed a beam current monitoring system based on the signals from an induction torus positioned at the beam exit of the waveguide and from a graphite beam collimator.ResultsThe stability of the output over repeated measurements was found to be good, with a standard deviation smaller than 1%. However, non‐negligible day‐to‐day variations of the beam output were observed. Those output variations showed different trends depending on the dose‐rate. The analysis of the relative output variation as a function of various beam parameters showed that in a given configuration, the dose‐rate could be reliably varied over three orders of magnitude. Interdependence effects on the output variation between the parameters were also observed. The beam energy and field size were found to be slightly dose‐rate‐dependent and suitable mainly for small animal irradiation. The beam monitoring system was able to measure in a reproducible way the total charge of electrons that exit the machine, as long as the electron pulse amplitude remains above a given threshold. Furthermore, we were able to relate the charge measured with the monitoring system to the absorbed dose in a solid water phantom.ConclusionThe Oriatron eRT6 was successfully commissioned for preclinical use and is currently in full operation, with studies being performed on the radiobiological effects of high dose‐per‐pulse irradiation.
A cross‐sectional study of stress and its sources among health professional students at Makerere University, Uganda
Authors: Amanya Sharon Bright , Nakitende Joyce , Ngabirano Tom Denis 
Published: December 2017

AbstractAimTo assess prevalence of stress and its sources among undergraduate health professional students at Makerere University.DesignThis was a descriptive cross‐sectional study using quantitative methods of data collection.MethodsThe study was conducted among 258 undergraduate health professional students (Medical, Dental and, Nursing students) at Makerere University. From each programme, students were recruited proportionately, while being selected conveniently from each year of study. Stress was measured using the General Health Questionnaire 12 and stressors assessed using a questionnaire developed from literature. After obtaining ethics approval, data were collected from consenting students. Data collected were analysed using SPSS statistical program.ResultsThe prevalence of stress was found to be 57.4% and stressors of academic and psychosocial origin were most frequently reported. The top stressors included; academic curriculum (38%), dissatisfaction with class lectures (30.9%), long distance walk (29.5%), lack of time for recreation (28.9%), performance in examination (28.3%), lack of special guidance from faculty (26.7%) and high parental expectations (26.7%).
Theoretical study of the furfuryl benzoate and furfuryl acetate pyrolysis
Authors: Mora Jose R. , Rincón Luis , Javier Torres F. , Zambrano Cesar H. , Muñoz Carlos 
Published: December 2017

AbstractIn the present work, the pyrolysis reaction mechanism of both furfuryl benzoate and furfuryl acetate was evaluated at the M06/6‐311++g(d,p) level. The uncommon methylenecyclobutenone compound and either the benzoic or the acetic acid were determined as the products of a multistep process consisting in two [3 + 3] rearrangements and a subsequent hydrogen α‐elimination step, through a cyclic 5‐membered transition state (TS), being the latter the rate‐limiting step for both reactants. Furthermore, a deeper analysis on the basis of the reaction force formalism showed that the TS is formed in two stages: The first one is characterized by the weakening of the C─O bond, and the second one is where the H atom is transferred from the C atom to its nearest O atom. The H─O bond formation was determined to contribute the most to the electronic activity occurring during the TS formation as suggested by a reaction electronic flux analysis. Accordingly, natural bond orbital calculations showed that the most significant changes occur in the charge distribution of the O and H atoms. Finally, a negligible effect of the substituting group on the reaction was determined since similar activation energies were obtained for the pyrolysis of furfuryl benzoate and furfuryl acetate; however, a minor difference was evidenced in the reaction force results. In this sense, the structural contribution to the activation energy is larger than the electronic one for the furfuryl benzoate reaction,
, whereas the opposite is observed for the furfuryl acetate reaction,
.