bluuebunny/crossref_metadata_2025_split huggingface dataset:
Vortex shape and gas‐liquid hydrodynamics in unbaffled stirred tank
Authors: Prakash Baranivignesh , Bhatelia Tejas , Wadnerkar Divyamaan , Shah Milinkumar T. , Pareek Vishnu K. , Utikar Ranjeet P. 
Published: December 2018

AbstractThe present study investigated the effect of impeller speed and vortex ingestion on vortex shape, gas holdup, and bubble size distribution in an unbaffled stirred tank using optical probe measurements. Further, the ability of the volume of the fluid model to predict vortex shape was examined. Without vortex ingestion, an increase in impeller speed resulted in a significant variation in vortex shape, whereas it had a negligible effect on vortex shape with ingestion. This suggests that when vortex ingestion occurred, most of the energy was consumed for the dispersion of gas rather than the deformation of the gas‐liquid interface. It was observed that a large number of gas bubbles were entrained into the vortex core around the impeller region, which led to a lower gas holdup at the top axial locations. An increase in the impeller speed also resulted in the formation of larger bubbles. The absence of baffles limits shear for bubble break up, resulting in larger bubbles above the impeller plane.
Cost‐effectiveness of a patient navigation intervention to increase colonoscopy screening among low‐income adults in New Hampshire
Authors: Rice Ketra , Sharma Krishna , Li Chunyu , Butterly Lynn , Gersten Joanne , DeGroff Amy 
Published: December 2018

AbstractBackgroundColonoscopy is the most widely used colorectal cancer (CRC) screening test in the United States. Through the detection and removal of potentially precancerous polyps, it can prevent CRC. However, CRC screening remains low among adults who are recommended for screening. The New Hampshire Colorectal Cancer Screening Program implemented a patient navigation (PN) intervention to increase colonoscopy screening among low‐income patients in health centers in New Hampshire. In the current study, the authors examined the cost‐effectiveness of this intervention.MethodsA decision tree model was constructed using Markov state transitions to calculate the costs and effectiveness associated with PN. Costs were calculated for the implementation of PN in a statewide public health program and in endoscopy centers. The main study outcome was colonoscopy screening completion. The main decision variable was the incremental cost‐effectiveness ratio associated with the PN intervention compared with usual care.ResultsThe average cost per screening with PN was $1089 (95% confidence interval, $1075‐$1103) compared with $894 with usual care (95% confidence interval, $886‐$908). Among patients who were navigated, approximately 96.2% completed colonoscopy screening compared with 69.3% of those receiving usual care (odds ratio, 11.2; P <. 001). The incremental cost‐effectiveness ratio indicated that 1 additional screening completion cost approximately $725 in a public health program and $548 in an endoscopy center with PN compared with usual care, both of which are less than the average Medicare reimbursement of $737 for a colonoscopy procedure.ConclusionsPN was found to be cost‐effective in increasing colonoscopy screening among low‐income adults in the New Hampshire Colorectal Cancer Screening Program, even at the threshold of current Medicare reimbursement rates for colonoscopy. The results of the current study support the implementation of PN in statewide public health programs and endoscopy centers.
Germline mutations of renal cancer predisposition genes and clinical relevance in Chinese patients with sporadic, early‐onset disease
Authors: Wu Junlong , Wang Hongkai , Ricketts Christopher J. , Yang Youfeng , Merino Maria J. , Zhang Hailiang , Shi Guohai , Gan Hualei , Linehan W. Marston , Zhu Yao , Ye Dingwei 
Published: December 2018

BackgroundAn inherited susceptibility to renal cancers is associated with multiple predisposing genes, but most screening tests are limited to patients with a family history. Next‐generation sequencing (NGS)–based multigene panels provide an efficient and adaptable tool for investigating pathogenic germline mutations on a larger scale. This study investigated the frequency of pathogenic germline mutations in renal cancer predisposition genes in patients with sporadic, early‐onset disease.MethodsAn NGS‐based panel of 23 known and potential renal cancer predisposition genes was used to analyze germline mutations in 190 unrelated Chinese patients under the age of 45 years who presented with renal tumors. The detected variants were filtered for pathogenicity, and then their frequencies were calculated and correlated with clinical features. Germline variants of the fumarate hydratase (FH) and BRCA1‐associated protein 1 (BAP1) genes were comprehensively analyzed because of their aggressive potential.ResultsIn total, 18 patients (9.5%) had germline mutations in 10 genes. Twelve of these 18 patients had alterations in renal cancer predisposition genes (6.3%), and 6 patients had mutations in potential predisposition genes such as BRCA1/2. Notably, pathogenic mutation carriers had a significant family history in second‐degree relatives in comparison with those without pathogenic mutations (P < .001). Variants of unknown clinical significance in FH and BAP1 demonstrated evidence of additional somatic loss in tumors.ConclusionsIn patients with early‐onset disease, a multigene panel identified a high pathogenic germline mutation rate in renal cancer predisposition genes. This study emphasizes the importance of screening patients with early‐onset disease for mutations in cancer predisposition genes. Germline screening should be encouraged in early‐onset patients to provide personalized medicine and improve patient outcomes.
Enhanced Stability and Optical Absorption in the Perovskite‐Based Compounds MA1−xCsxPbI3−yBry
Authors: Chang Junli , Yuan Hongkuan , Wang Biao , Huang Yuhong , Chen Xiaorui , Chen Hong 
Published: December 2018

AbstractOrganometal halide perovskites have been outstanding from enormous amount of functional materials thanks to their highly cost‐effective processability and prominent light harvesting capacity. Unfortunately, poor long‐term stability seriously hinders their further development. The recent experimental observations suggest that Cesium is a promising candidate to enhance the stability of MAPbI3. To explore the inherent mechanism, a first‐principles investigation based on density functional theory, including hybrid functional, has been performed to analyze the electronic and optical properties of perovskite series MA0.75Cs0.25PbI3−yBry. The results indicate that perovskite compound MA0.75Cs0.25PbI2Br is significantly superior to the other doped series in terms of optical absorption within the visible‐light range. In the meanwhile, both Bader charge analysis and charge density distribution show that the compound of MA0.75Cs0.25PbI2Br is the most stable among all the doped perovskite series. Moreover, it is clearly manifested that the impact of cesium is mainly embodied in the enhancement of the stability rather than in the improvement of optical absorption. Our study sheds a new light on screening new‐type light harvesting materials, and provides theoretical insight into the rationale design of highly efficient and stable photovoltaic devices based on these functional materials.
Modulation of Excited‐State Proton‐Transfer Dynamics inside the Nanocavity of Microheterogeneous Systems: Microenvironment‐Sensitive Förster Energy Transfer to Riboflavin
Authors: Dey Nilanjan , Biswakarma Dipen , Bajpai Alankriti , Moorthy Jarugu Narasimha , Bhattacharya Santanu 
Published: December 2018

AbstractThe excited‐state proton‐transfer efficiency of a tetraarylpyrene derivative, 1,3,6,8‐tetrakis(4‐hydroxy‐2,6‐dimethylphenyl)pyrene (TDMPP), was investigated thoroughly in the presence of various surfactant assemblies, such as micelles and vesicles. The confined microheterogeneous environments can significantly retard the extent of the excited‐state proton‐transfer process, resulting in a distinguishable optical signal compared to that in the bulk medium. Physical characteristics of the surfactant assemblies, such as order, interfacial hydration, and surface charge, influence the proton transfer process and allow multiparametric sensing. A higher degree of interfacial hydration facilitates the proton‐transfer process, while the positively charged head groups of the surfactants specifically stabilize the anionic form of the probe (TDMPP−O*). Furthermore, Forster energy transfer from the probe to riboflavin was studied in a phospholipid membrane, wherein the relative ratio of the neutral versus anionic forms (TDMPP‐OH/TDMPP−O*) was found to influence the extent of energy transfer. Overall, we demonstrate how an ultrafast photophysical process, that is, the excited‐state proton transfer, can be influenced by the microenvironment.
Numerical Analysis of Thermal Stress in Semi‐Transparent Oxide Crystals Grown by Czochralski and EFG Methods
Authors: Stelian Carmen , Muzy Jessica , Labor Serge , Fivel Marc , Cabane Hugues , Duffar Thierry 
Published: December 2018

AbstractCrystal growth of oxides is generally difficult since large curvatures of the growth interface in these systems generate high thermal stress, dislocations and crystal cracking. Three‐dimensional numerical modeling is applied to investigate thermal stress distribution in sapphire and langatate La3Ta0.5Ga5.5O14 (LGT) semi‐transparent crystals grown by Czochralski (Cz) and Edge‐defined Film‐fed Growth (EFG) techniques. The analysis of thermal stress distribution in a sapphire ingot grown in a Czochralski furnace shows high von Mises stresses distributed almost symmetrically on large areas in the crystal. Thermal stress computations for piezoelectric langatate crystals grown in a Czochralski configuration show non‐symmetrical von Mises distribution with higher stress on one side of the ingot. These numerical results are in agreement with experimental results showing non‐symmetrical cracking at the outer surface of the crystal. 3D modeling of multi‐die EFG growth of white sapphire ribbons shows that the von Mises stress is almost constant when the number of ribbons is increased from two to ten. Two models are applied to simulate the internal radiative heat transfer in the sapphire crystals: P1 approximation and the Rosseland radiation model. Numerical results show that applying Rosseland formula introduces significant errors in temperature field calculations especially in the case of the EFG configuration.
Aqueous‐Phase Transformation of Glucose into Hydroxymethylfurfural and Levulinic Acid by Combining Homogeneous and Heterogeneous Catalysis
Authors: Garcés Diego , Faba Laura , Díaz Eva , Ordóñez Salvador 
Published: December 2018

AbstractHomogeneous (HCl) and heterogeneous catalysts (various zeolites) were combined to enhance the upgrading of glucose into two different platform molecules: 5‐hydroxymethylfurfural (HMF) and levulinic acid (LA). β‐Zeolite was the most active material for the glucose isomerization to fructose, improving also the activity of HCl for the subsequent steps. Reaction time, temperature, and pH were then modified, identifying 140 °C, 200 ppm of HCl, and 5 h as the optimum conditions for HMF formation (41 % selectivity; 0.06 mol L−1) and 140 °C, 400 ppm of HCl, and 24 h for LA formation (34 % selectivity; 0.12 mol L−1). This new approach is also relevant because of significant changes to the mechanism for humins formation. All results are successfully fitted to a kinetic model simultaneously considering both catalytic mechanisms.
Design and analysis of differential ring voltage controlled oscillator for wide tuning range and low power applications
Authors: Askari Shirin , Saneei Mohsen 
Published: December 2018

SummaryVoltage‐controlled oscillator (VCO) is the most basic component required for all wireless and communication systems. In this article, a four‐stage differential ring VCO with two control voltages for wide tuning range is proposed. This VCO uses the dual‐delay loop technique for high operation frequency. Also, a low‐VT NMOS transistor is used in series with pull down network of the proposed VCO delay cell to achieve low frequencies. Prelayout simulation of the proposed VCO is performed in 65‐nm TSMC CMOS technology in Cadence software under 1.2‐V supply voltage. The tuning range of the proposed VCO varies from 1 MHz to 13.8 GHz and has been improved by 19.77% compared to other works. The power consumption of this low power VCO is between 29.3 μW to 1.715 mW. The phase noise of the proposed circuit is −82.3 dBc/Hz at 1 MHz offset frequency and −106.9 dBc/Hz at 10 MHz offset frequency from 5.161 GHz center frequency, while its area is 102.457 μm2. This design demonstrates other benefits in low power consumption and area compared with other ring oscillators.
Long‐term evolution of the Old Rhine estuary: Unravelling effects of changing boundary conditions and inherited landscape
Authors: de Haas Tjalling , van der Valk Lambertus , Cohen Kim M. , Pierik Harm Jan , Weisscher Steven A. H. , Hijma Marc P. , van der Spek Ad J. F. , Kleinhans Maarten G. 
Published: December 2018

AbstractThe long‐term morphodynamic evolution of estuaries depends on a combination of antecedent topography and boundary conditions, including fluvial input, sea‐level change and regional‐landscape interactions. Identifying effects of such boundary conditions on estuary evolution is important to anticipate future changes in specific boundary conditions and for hindcasting with numerical and physical models. A comprehensive synthesis of the evolution of the former Old Rhine estuary is presented here, together with its boundary conditions over its full lifespan from 6,500 to 1,000 cal. yr bp. This system formed during a period of sea‐level high stand, during which the estuary served as the main River Rhine outlet. The estuary went through three stages of evolution: a maturation phase in a wide infilling back‐barrier basin, a stable mature phase and an abandoning phase, both in a laterally confined setting. The Old Rhine River formed by a river avulsion around 6,500 cal. yr bp that connected to a tidal channel within a large back‐barrier basin. Decelerating sea‐level rise caused the back‐barrier basin to silt up around 5,700 cal. yr bp, resulting in shoreline progradation by beach‐barrier formation until ∼2,000 cal. yr bp. Beach‐barrier formation along the coast and natural levee formation along the river triggered peat formation in the coastal plain, laterally constraining the estuary and limiting overbank deposition, which caused most sediment to accumulate offshore. The abandoning phase started around 2,200 cal. yr bp when a series of upstream avulsions led to a substantial reduction in fluvial input. This induced a period of enhanced estuarine overbank clay deposition that continued into near‐complete silting up and estuary closure around 1200 ad. These findings exemplify how tidal systems, formed in wide coastal plains during sea‐level high stand, depend on antecedent conditions, and how they respond to connection and disconnection of a large river over long, millennial timescales.
Radial Glia in Echinoderms
Authors: Mashanov Vladimir , Zueva Olga 
Published: December 2018

AbstractRadial glial cells are crucial in vertebrate neural development and regeneration. It has been recently proposed that this neurogenic cell type might be older than the chordate lineage itself and might have been present in the last common deuterostome ancestor. Here, we summarize the results of recent studies on radial glia in echinoderms, a highly regenerative phylum of marine invertebrates with shared ancestry to chordates. We discuss the involvement of these cells in both homeostatic neurogenesis and post‐traumatic neural regeneration, compare the features of radial glia in echinoderms and chordates to each other, and review the molecular mechanisms that control differentiation and plasticity of the echinoderm radial glia. Overall, studies on echinoderm radial glia provide a unique opportunity to understand the fundamental biology of this cell type from evolutionary and comparative perspectives.
Developmental Exposure to Psychostimulant Primes Activity‐dependent Gene Induction in Frontal Cortex
Authors: Ye Yizhou , Liu Qing , Zhang Wenyu , Mastwal Surjeet , Wang Kuan Hong 
Published: December 2018

AbstractPerinatal neurodevelopment involves extensive formation of neural connections and onset of activity‐dependent gene expression for synaptic function and plasticity. Exposure to psychostimulants at this stage imposes significant risks for developing cognitive and affective disorders later in life. However, how developmental exposure to psychostimulants may induce long‐lasting molecular changes relevant to neural circuit function remains incompletely understood. In this study, we investigated the impacts of psychostimulant amphetamine on the activity‐dependent induction of synaptic adaptor molecule Arc in the frontal cortex of neonatal mice. We found that transient exposure to amphetamine not only amplifies activity‐dependent Arc mRNA expression immediately, but also potentiates subsequent induction of Arc mRNA in the absence of amphetamine. This priming effect is associated with a rapid and persistent increase in histone mono‐methylation (H3K4me1), a marker for transcriptionally permissive chromatin, at the Arc locus, but not any long‐lasting change in the phosphorylation of upstream transcription factor CREB. Furthermore, the increase in H3K4me1 at the Arc locus requires dopamine receptor signaling, and the priming of Arc expression correlates with the dopaminergic innervation pattern in the frontal cortex. Together, our results demonstrate that developmental exposure to psychostimulant amphetamine induces long‐lasting chromatin changes and primes activity‐dependent Arc gene induction. These findings reveal the molecular targets of psychostimulant during perinatal development that may contribute to long‐term psychiatric risks.
Identification of new urinary gamma‐hydroxybutyric acid markers applying untargeted metabolomics analysis following placebo‐controlled administration to humans
Authors: Steuer Andrea E. , Raeber Justine , Steuer Christian , Boxler Martina I. , Dornbierer Dario A. , Bosch Oliver G. , Quednow Boris B. , Seifritz Erich , Kraemer Thomas 
Published: December 2018

AbstractGamma‐hydroxybutyrate (GHB) is a short‐chain fatty acid that occurs naturally in the mammalian brain and is prescribed as a medication against narcolepsy or used as a drug of abuse. Particularly, its use as a knock‐out drug in cases of drug‐facilitated crimes is of major importance in forensic toxicology. Because of its rapid metabolism and resulting narrow detection windows (<12 hours in urine), detection of GHB remains challenging. Thus, there is an urgent call for new markers to improve the reliable detection of GHB use. In the framework of a randomized, placebo‐controlled, crossover study in 20 healthy male volunteers, urine samples obtained 4.5 hours post‐administration were submitted to untargeted mass spectrometry [MS, quadrupole time of flight (QTOF)] analysis to identify possible new markers of GHB intake. MS data from four different analytical methods (reversed phase and hydrophilic interaction liquid chromatography; positive and negative electrospray ionization) were filtered for significantly changed features applying univariate and multivariate statistics. From the resulting 42 compounds of interest, 8 were finally identified including conjugates of GHB with carnitine, glutamate, and glycine as well as the endogenous compounds glycolate and succinylcarnitine. While GHB conjugates were only detectable in the GHB, but not in the placebo group, glycolate and succinylcarnitine were present in both groups albeit significantly increased through GHB intake. Untargeted metabolomics proved as a suitable tool for the non‐hypothesis driven identification of new GHB markers. However, more studies on actual concentrations, detection windows, and stability will be necessary to assess the suitability of these markers for routine application.
Biomass‐derived Nitrogen and Phosphorus Co‐doped Hierarchical Micro/mesoporous Carbon Materials for High‐performance Non‐enzymatic H2O2 Sensing
Authors: Liu Sen , Han Tianyi , Wang Ziying , Fei Teng , Zhang Tong 
Published: December 2018

AbstractNitrogen and phosphorus co‐doped hierarchical micro/mesoporous carbon (N,P‐MMC) was prepared by simple thermal treatment of freeze‐dried okra in the absence of any other additives. The 0.96 wt % of N and 1.47 wt % of P were simultaneously introduced into the graphitic framework of N,P‐MMC, which also possesses hierarchical porous structure with mesopores centered at 3.6 nm and micropores centered at 0.79 nm. Most importantly, N,P‐MMC carbon exhibits excellent catalytic activity for electrocatalytic reduction of H2O2, resulting in a new strategy to construct non‐enzymatic H2O2 sensor. The N,P‐MMC‐based H2O2 sensor displays two linear detection range about 0.1 mM–10 mM (R2=0.9993) and 20 mM–200 mM (R2=0.9989), respectively. The detection limit is estimated to be 6.8 μM at a signal‐to‐noise ratio of 3. These findings provide insights into synthesizing functional heteroatoms doped porous carbon materials for biosensing applications.
Fractionation and release of Cd, Cu, Pb, Mn, and Zn from historically contaminated river sediment in Southern China: Effect of time and pH
Authors: Xu Xinrong , Huang Renlong , Liu Junguang , Shu Yuehong 
Published: December 2018

Abstract

The release of in situ heavy metals (cadmium [Cd], copper [Cu], lead [Pb], manganese [Mn], and zinc [Zn]) from contaminated river sediment near a Cu–iron mine in South China was experimentally studied. The effects of pH values and the kinetics of heavy metal release were investigated. In addition, species of the 5 metals in the sediment were determined as a function of pH and time. Rates and extents of metal desorption were studied over 30 d, and a 3-parameter, 2-compartment model was used to analyze the desorption kinetics. The rate constants (ks) for the slowly desorbing fraction of heavy metals were found to be 5 to 6 orders of magnitude lower than the corresponding rate constants (kr) for the rapidly desorbing fraction, suggesting that slow desorption is the rate-limiting step. The partition coefficients (Kd) varied significantly among metals, on the order Pb &gt; Cu &gt;Zn &gt; Cd &gt; Mn, indicating that the sediment had a much higher retention capability for strongly hydrolyzed metals than for weakly hydrolyzed ones. The amount of metals released from the sediment decreased dramatically at the final pH of 2 to 4 and leveled off in the pH range of 5 to 8. Release time and pH exhibited a varied influence on the fractionation of metals, and had a more remarkable influence on more mobile fractions and hardly any effect on the residual fraction during the desorption process. The fractionation of strongly adsorbing metals like Pb was not as dependent on release time and pH as it was for the weakly bonded metals like Mn and Cd. The results indicate that in situ heavy metals may exhibit a sustainable potential for release and may increase health risks when the pH of the river is lowered. Environ Toxicol Chem 2019;38:464–473. © 2018 SETAC.