bluuebunny/crossref_metadata_2025_split huggingface dataset:
Distinct neural mechanisms for remembering when an event occurred
Authors: Jenkins Lucas J. , Ranganath Charan 
Published: February 2016

ABSTRACTEvents are often remembered as having occurred in a specific order, but almost nothing is known about how the brain encodes this temporal information. It is commonly assumed that temporal information is encoded via a single mechanism, based either on the temporal context in which the event occurred or inferred from the strength of the memory trace itself. By analyzing time‐dependent changes in activity patterns, we show that the distinctiveness of contextual representations in the hippocampus and anterior and medial prefrontal cortex was associated with accurate recency memory. In contrast, overall activation in the perirhinal and lateral prefrontal cortices predicted whether an object would be judged more recent, regardless of accuracy. These results demonstrate that temporal information was encoded through at least two complementary neural mechanisms. © 2016 Wiley Periodicals, Inc.
Depth‐dependent stratum corneum permeability in human skin in vitro
Authors: Cadavona John Jay P. , Zhu Hanjiang , Hui Xiaoying , Jung Eui‐Chang , Maibach Howard I. 
Published: February 2016

AbstractThe stratum corneum (SC), a permeable membrane, limits percutaneous penetration. As SC chemical and structural properties responsible for skin barrier function appear depth‐related, we conducted an in vitro dermatopharmacokinetic study on intact and adhesive tape‐stripped skin samples to clarify whether SC is a homogeneous barrier for chemical transport. SC concentration–thickness profiles were determined for four C‐14 labeled model chemicals, panthenol, benzoic acid, paraoxon and butenafine, using the tape‐stripping approach. Data analysis with the unsteady‐state diffusion equation of Fick's second law permitted a chemical diffusion coefficient in SC. To evaluate the consistency of SC permeability from its surface to lower levels, the skin was tape‐stripped five to 10 times to remove the upper cell layers before chemical application, such that diffusion coefficients could be determined from three SC depth levels (0, 5 and 10 tape strips). Results suggested the depth‐dependency of SC permeability to panthenol, benzoic acid and butenafine; the diffusion coefficient of panthenol decreased significantly after the first five tape strips and subsequently remained consistent. A progressive increase in diffusion coefficients of benzoic acid and butenafine was observed as tape‐stripping levels increased. The removal of superficial SC did not result in a significant difference in the paraoxon diffusion coefficient. For individual chemicals, a variation in the diffusion coefficient from SC surface to deeper layers agreed with the change of the diffusion coefficient over time in intact skin. Characterization of the SC properties contributing to the depth‐dependent SC permeability will hopefully provide further insight to skin penetration/decontamination. Copyright © 2016 John Wiley & Sons, Ltd.
Improved cell infiltration of electrospun nanofiber mats for layered tissue constructs
Authors: Mahjour Seyed Babak , Sefat Farshid , Polunin Yevgeniy , Wang Lichen , Wang Hongjun 
Published: February 2016

AbstractWhile achieving the spatial organization of cells within 3D assembled nanofiber/cell constructs via nanofiber‐enabled cell layering, the small sizes of inter‐fiber pores of the electrospun nanofiber mats could significantly limit cell penetration across the layers for rapid formation of an integrated tissue construct. To address this challenge, efforts were made to improve cell‐infiltration of electrospun nanofiber mats by modulating the density distribution and spatial organization of the fibers during electrospinning. Collection of collagen‐containing electrospun nanofibers (300–600 nm in diameter) onto the surface of a stainless steel metal mesh (1 mm × 1 mm in mesh size) led to the periodic alternation of fiber density from densely packed to loosely arranged distribution within the same mat, in which the densely packed fibers maintained the structural integrity while the region of loose fibers allowed for cell penetration. Along with improved cell infiltration, the distinct fiber organization between dense and loose fiber regions also induced different morphology of fibroblasts (stellate vs. elongated spindle‐like). Assembly of cell‐seeded nanofiber sheets into 3D constructs with such periodically organized nanofiber mats further demonstrated their advantages in improving cell penetration across layers in comparison to either random or aligned nanofiber mats. Taken together, modulation of nanofiber density to enlarge the pore size is effective to improve cell infiltration through electrospun mats for better tissue formation. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 1479–1488, 2016.
Comparison of the Automated cobas u 701 Urine Microscopy and UF‐1000i Flow Cytometry Systems and Manual Microscopy in the Examination of Urine Sediments
Authors: Lee Wonmok , Ha Jung‐Sook , Ryoo Nam‐Hee 
Published: February 2016

BackgroundThe cobas u 701, a new automated image‐based urine sediment analyzer, was introduced recently. In this study, we compared its performance with that of UF‐1000i flow cytometry and manual microscopy in the examination of urine sediments.MethodsPrecision, linearity, and carry‐over were determined for the two urine sediment analyzers. For a comparison of the method, 300 urine samples were examined by the automated analyzers and by manual microscopy using a KOVA chamber.ResultsWithin‐run coefficients of variation (CVs) for the control materials were 7.0–8.8% and 1.7–5.7% for the cobas u 701 and UF‐1000i systems, respectively. Between‐run CVs were 8.5–9.8% and 2.7–5.4%, respectively. Both instruments showed good linearity and negligible carry‐over. For red blood cells (RBC), white blood cells (WBC), and epithelial cells (EPI), the overall concordance rates within one grade of difference among the three methods were good (78.6–86.0%, 88.7–93.8%, and 81.3–90.7%, respectively). The concordance rate for casts was poor (66.5–68.9%).ConclusionCompared with manual microscopy, the two automated sediment analyzers tested in this study showed satisfactory analytical performances for RBC, WBC, and EPI. However, for other urine sediment particles confirmation by visual microscopy is still required.
Overestimated Arctic warming and underestimated Eurasia mid‐latitude warming in CMIP5 simulations
Authors: Xie Yongkun , Liu Yuzhi , Huang Jianping 
Published: February 2016

ABSTRACTThe surface air temperature (SAT) trends from historical simulations of the Coupled Model Intercomparison Project Phase 5 (CMIP5) were compared with observations for the period of 1955–2004. The observed spatial pattern of SAT trends was strikingly different from the CMIP5‐historical simulations over mid‐ and high‐latitude Northern Hemisphere. The strongest observed warming for the Eurasian Continent was over mid latitudes. However, the CMIP5 historical simulations indicated enhanced warming over higher latitudes, and the warming trends increased from low to higher latitudes. The zonal mean SAT trends indicated overestimated warming in high‐latitude and underestimated warming in mid‐latitude land over Northern Hemisphere in CMIP5 historical simulations, which resulted in opposite trends in the meridional temperature gradient over high latitudes compared with observations. The overestimated Arctic and underestimated Eurasia mid‐latitude warming only occurred in cold season. Further comparison of the results of CMIP5 models from the Atmospheric Model Intercomparison Project and historical simulations revealed that model bias in sea surface temperature and the exaggerated response of temperature change to Arctic sea ice decline are possible reasons for poorly simulated Arctic and Eurasia mid‐latitude temperature change.
Changes in climate extremes over major river basins of India
Authors: Deshpande N. R. , Kothawale D. R. , Kulkarni A. 
Published: February 2016

ABSTRACTTemporal changes in the extreme rainfall and temperature characteristics of major river basins on a daily time scale are examined using high‐resolution gridded daily rainfall (1951–2014) and temperature (1951–2013) data sets. Trend analysis is carried out to examine the temporal changes in the frequency, area covered and intensity of the extreme rainfall and temperature events. Rainfall of 10 cm during southwest monsoon season (JJAS), maximum temperature of 40 °C during summer season (MAM) and minimum temperature of 10 °C during the winter season (DJF) have been used as the thresholds to define the extreme weather events of rainfall and temperature data in these river basins. Analysis indicates that during monsoon season zero rainfall days are increasing in all the river basins except some parts of the Krishna and Peninsular river basins. River basins located in the central parts of India show significant increase in the area covered by the heavy rainfall episodes and their intensity. Substantial rise in the monthly maximum temperatures is seen in the Krishna, Peninsular and West Coast river basins. Frequency, area coverage and intensity of hot days during summer season are increasing significantly in the Krishna and Peninsular river basins, while no substantial change has been observed for cold days during winter season in any river basins of the study.
Racial, ethnic, and socioeconomic disparities in pituitary surgery outcomes
Authors: Goljo Erden , Parasher Arjun K. , Iloreta Alfred M. , Shrivastava Raj , Govindaraj Satish 
Published: February 2016

Objectives/HypothesisTo investigate the association of race, ethnicity, socioeconomic status, and hospital volume with outcomes in pituitary surgery.Study DesignRetrospective cross‐sectional study of the 2008‐2012 National (Nationwide) Inpatient Sample.MethodsPatient demographics, hospital characteristics, postoperative complications, and in‐hospital mortality for patients undergoing pituitary surgery were compared between white, black, and Hispanic patients. Hierarchal logistic regression analysis was used to assess the association of patient and hospital variables on complication rates.ResultsA total of 8,812 patients met the inclusion criteria, and 5,924 (67.2%) patients were white, 1,590 (18.0%) were black, and 1,296 (14.7%) were Hispanic. Black and Hispanic patients were more likely to live in the poorest income areas, be insured with Medicaid, and be treated at lower‐volume pituitary surgery centers. Patients with Medicaid had a higher likelihood of complications compared to Medicare patients, whereas patients with private insurance were significantly less likely to experience any complications. Likelihood of complications was significantly higher for patients treated at lower‐volume pituitary surgery centers. When controlled for patient and hospital characteristics, regression analysis showed that the likelihood of postoperative complications was higher in black and Hispanic patients compared to white patients.ConclusionsRacial, ethnic, and socioeconomic disparities exist for outcomes after pituitary surgery. Black and Hispanic patients have worse postoperative outcomes compared to white patients, as well as disproportionate utilization of Medicaid and low‐volume pituitary surgery centers. Further investigations are necessary to uncover the sources of these disparities in an effort to provide safer and more affordable care to all patients.Level of Evidence2c. Laryngoscope, 126:808–814, 2016
Effects of increased CO2 concentration on nutrient limited coastal summer plankton depend on temperature
Authors: Paul Carolin , Sommer Ulrich , Garzke Jessica , Moustaka‐Gouni Maria , Paul Allanah , Matthiessen Birte 
Published: February 2016

AbstractIncreasing seawater temperature and CO2 concentrations both are expected to increase coastal phytoplankton biomass and carbon to nutrient ratios in nutrient limited seasonally stratified summer conditions. This is because temperature enhances phytoplankton growth while grazing is suggested to be reduced during such bottom‐up controlled situations. In addition, enhanced CO2 concentrations potentially favor phytoplankton species, that otherwise depend on costly carbon concentrating mechanisms (CCM). The trophic consequences for consumers under such conditions, however, remain little understood. We set out to experimentally explore the combined effects of increasing temperature and CO2 concentration for phytoplankton biomass and stoichiometry and the consequences for trophic transfer (here for copepods) on a natural nutrient limited Baltic Sea summer plankton community. The results show, that warming effects were translated to the next trophic level by switching the system from a bottom‐up controlled to a mainly top‐down controlled one. This was reflected in significantly down‐grazed phytoplankton and increased zooplankton abundance in the warm temperature treatment (22.5°C). Additionally, at low temperature (16.5°C) rising CO2 concentrations significantly increased phytoplankton biomass. The latter effect however, was due to direct negative impact of CO2 on copepod nauplii which released phytoplankton from grazing in the cold but not in the warm treatments. Our results suggest that future seawater warming has the potential to switch trophic relations between phytoplankton and their grazers under nutrient limited conditions with the consequence of potentially disguising CO2 effects on coastal phytoplankton biomass.
Aqueous Photoelectrochemical Reduction of Anthraquinone Disulfonate at Organic Polymer Films
Authors: Chowdhury Pankaj , Fortin Patrick , Suppes Graeme , Holdcroft Steven 
Published: February 2016

The photoelectrochemistry (PEC) of poly(3‐hexylthiophene) (P3HT) is investigated by studying the photocathodic reduction of anthraquinone‐2,7‐disulfonate (AQ27DS). A photocurrent of ≈ 100 μA cm−2 is obtained using ≈ 5 × 10−3 m AQ27DS and 100 mW cm−2 visible light. The photon‐to current‐efficiency approaches ≈ 1% when irradiated with low intensity monochromatic light. The photoreduction proceeds by either a 2‐electron, 2‐proton, or 2‐electron, 1‐proton process depending on the solution pH. The band energy levels of P3HT shift by ≈ 150 mV in contact with aqueous solutions over a 1–12 pH range, and considerable more in the presence of AQ27DS during PEC, to the extent that Fermi level pinning occurs. This work reveals that the efficiency of electron–hole separation is required to improve photoefficiency and the interaction of redox couples with the P3HT semiconductor interface is warranted in order to understand the photovoltages developed across the semiconductor/electrolyte interfaces.
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Disposition of flavonoids via recycling: Direct biliary excretion of enterically or extrahepatically derived flavonoid glucuronides
Authors: Zeng Min , Sun Rongjin , Basu Sumit , Ma Yong , Ge Shufan , Yin Taijun , Gao Song , Zhang Jun , Hu Ming 
Published: February 2016

ScopeEnterohepatic recycling is often thought to involve mostly phase II metabolites generated in the liver. This study aims to determine if direct biliary excretion of extrahepatically generated glucuronides would also enable recycling.Methods and resultsConventional and modified intestinal perfusion models along with intestinal and liver microsomes were used to determine the contribution of extrahepatically derived glucuronides. Glucuronidation of four flavonoids (genistein, biochanin A, apigenin, and chrysin at 2.5–20 μM) were generally more rapid in the hepatic than intestinal microsomes. Furthermore, when aglycones (at 10 μM each) were perfused, larger (1.7–9 fold) amounts of glucuronides were found in the bile than in the luminal perfusate. However, higher concentrations of glucuronides were not found in jugular vein than portal vein, and apigenin glucuronide actually displayed a significantly lower concentration in jugular vein (<1 nM) than portal vein (≈4 nM). A direct portal infusion of four flavonoid glucuronides (5.9–10.4 μM perfused at 2 mL/h) showed that the vast majority (>65%) of the glucuronides (except for biochanin A glucuronide) administered were efficiently excreted into the bile.ConclusionDirect biliary excretion of extrahepatically generated flavonoid glucuronides is a highly efficient clearance mechanism, which should enable enterohepatic recycling of flavonoids without hepatic conjugating enzymes.
Prospective heart tracking for whole‐heart magnetic resonance angiography
Authors: Moghari Mehdi H. , Geva Tal , Powell Andrew J. 
Published: February 2016

PurposeTo develop a prospective respiratory‐gating technique (Heart‐NAV) for use with contrast‐enhanced three‐dimensional (3D) inversion recovery (IR) whole‐heart magnetic resonance angiography (MRA) acquisitions that directly tracks heart motion without creating image inflow artifact.MethodsWith Heart‐NAV, one of the startup pulses for the whole‐heart steady‐state free precession MRA sequence is used to collect the centerline of k‐space, and its one‐dimensional reconstruction is fed into the standard diaphragm‐navigator (NAV) signal analysis process to prospectively gate and track respiratory‐induced heart displacement. Ten healthy volunteers underwent non‐contrast whole‐heart MRA acquisitions using the conventional diaphragm‐NAV and Heart‐NAV with 5 and 10‐mm acceptance windows in a 1.5T scanner. Five patients underwent contrast‐enhanced IR whole‐heart MRA using a diaphragm‐NAV and Heart‐NAV with a 5‐mm acceptance window.ResultsFor non‐contrast whole‐heart MRA with both the 5 and 10‐mm acceptance windows, Heart‐NAV yielded coronary artery vessel sharpness and subjective visual scores that were not significantly different than those using a conventional diaphragm‐NAV. Scan time for Heart‐NAV was 10% shorter (p < 0.05). In patients undergoing contrast‐enhanced IR whole‐heart MRA, inflow artifact was seen with the diaphragm‐NAV but not with Heart‐NAV.ConclusionCompared with a conventional diaphragm‐NAV, Heart‐NAV achieves similar image quality in a slightly shorter scan time and eliminates inflow artifact. Magn Reson Med 77:759–765, 2017. © 2016 International Society for Magnetic Resonance in Medicine
Renewable building blocks for sustainable polyesters: new biotechnological routes for greener plastics
Authors: Pellis Alessandro , Herrero Acero Enrique , Gardossi Lucia , Ferrario Valerio , Guebitz Georg M 
Published: February 2016

AbstractThe next generation of plastics are expected to contribute to a massive reduction in the carbon footprint by the exploitation, in industrial productive processes, of renewable monomers such as polyols and dicarboxylic acids obtainable via biotechnological production. More specifically, there is a rising demand for advanced polyesters displaying new functional properties while meeting higher sustainability criteria. Polyesters are part of everyday life with applications in clothing, food packaging, car manufacturing and biomedical devices. This review is intended to provide an overview of the array of renewable building blocks already available for synthetic purposes and exploitable in the production of polyesters. Moreover, new greener routes for more environmentally friendly polyester production and processing are discussed, pointing out the major technological challenges. © 2016 Society of Chemical Industry
Experimental (FT‐IR) and theoretical (DFT) studies on prototropy and H‐bond formation for pyrazine‐2‐amidoxime
Authors: Głębocka Angelika , Raczyńska Ewa D. , Chylewska Agnieszka , Makowski Mariusz 
Published: February 2016

AbstractThe results of the first structural studies (with the use of both experimental and theoretical methods) on pyrazine‐2‐amidoxime (PAOX) were shown and discussed. FT‐IR spectra were recorded in different concentrations of the PAOX in apolar solvent to check the possibility of the inter‐ or intramolecular hydrogen‐bond formation. All possible tautomers–rotamers of PAOX were then theoretically considered at the DFT(B3LYP)/6‐311+G** level in vacuo. For selected isomers, calculations were also performed at higher levels of theory {B3LYP/6‐311+G(3df,2p) and G3B3}. Based on the results of DFT calculations, the most stable isomers were found, and their total free energies and infrared spectra were calculated. The energy variation plots for the N8C7N9O10 and N1C2C7N9 dihedral angles were also computed to find two energy barriers, one for E/Z isomerization around the C7N9 double bond and the other one for rotation of the pyrazinyl ring around the C2C7 single bond. The results show that the stability of the PAOX isomers strongly depend on their configuration and orientation of the substituents. The possibilities of inter‐ and intramolecular hydrogen bonds were also experimentally and theoretically checked. Finally, a potential of mean force was determined in CHCl3 for a dimer of PAOX with hexamethylphosphoramide. Both, experimental and theoretical results are in agreement. Copyright © 2016 John Wiley & Sons, Ltd.
Thwarting location privacy protection in location‐based social discovery services
Authors: Xue Minhui , Liu Yong , Ross Keith W. , Qian Haifeng 
Published: February 2016

AbstractLocation‐based social discovery (LBSD) services enable users to discover their geographic neighborhoods to make new friends. Original LBSD services were designed to provide the exact distances to nearby users. It has been shown that it is easy to pinpoint any target user's location by using trilateration based on the exact distances from three fake Global Positioning System locations to the target user. To defend against the trilateration attack, contemporary LBSD services then began to report distances of nearby users in concentric bands, for example, bands of 100 meters, rather than exact distances. In this paper, we investigate the user location privacy leakage problem in LBSD services reporting distances in discrete bands. Using number theory, we analytically show that by strategically placing multiple virtual probes with fake Global Positioning System locations, one can nevertheless localize user locations in band‐based LBSD. Our methodology is guaranteed to localize any reported user within a circle of radius no greater than one meter, even for LBSD services using large bands (such as 100 m as used by WeChat). Eventually, countermeasures are proposed to reduce location privacy leakage to the very minimum. To the best of our knowledge, this is the first work that explicitly exploits and quantifies user location privacy leakage in band‐based LBSD services. We expect our study to draw more public attention to this serious privacy issue and expectantly motivate better privacy preserving LBSD designs. Copyright © 2016 John Wiley & Sons, Ltd.
Hartung–Knapp method is not always conservative compared with fixed‐effect meta‐analysis
Authors: Wiksten Anna , Rücker Gerta , Schwarzer Guido 
Published: February 2016

A widely used method in classic random‐effects meta‐analysis is the DerSimonian–Laird method. An alternative meta‐analytical approach is the Hartung–Knapp method. This article reports results of an empirical comparison and a simulation study of these two methods and presents corresponding analytical results. For the empirical evaluation, we took 157 meta‐analyses with binary outcomes, analysed each one using both methods and performed a comparison of the results based on treatment estimates, standard errors and associated P‐values. In several simulation scenarios, we systematically evaluated coverage probabilities and confidence interval lengths. Generally, results are more conservative with the Hartung–Knapp method, giving wider confidence intervals and larger P‐values for the overall treatment effect. However, in some meta‐analyses with very homogeneous individual treatment results, the Hartung–Knapp method yields narrower confidence intervals and smaller P‐values than the classic random‐effects method, which in this situation, actually reduces to a fixed‐effect meta‐analysis. Therefore, it is recommended to conduct a sensitivity analysis based on the fixed‐effect model instead of solely relying on the result of the Hartung–Knapp random‐effects meta‐analysis. Copyright © 2016 John Wiley & Sons, Ltd.