bluuebunny/crossref_metadata_2025_split huggingface dataset:
Isotope hydrology of a tropical coffee agroforestry watershed: Seasonal and event‐based analyses
Authors: Welsh Kristen , Boll Jan , Sánchez‐Murillo Ricardo , Roupsard Olivier 
Published: May 2018

AbstractStable isotope variations are extremely useful for flow partitioning within the hydrologic cycle but remain poorly understood throughout the tropics, particularly in watersheds with rapidly infiltrating soils, such as Andisols in Central America. This study examines the fluctuations of stable isotope ratios (δ18O and δ2H) in the hydrologic components of a tropical coffee agroforestry watershed (~1 km2) with Andisol soils in Costa Rica. Samples were collected in precipitation, groundwater, springs, and stream water over 2 years. The local meteoric water line for the study site was δ2H = 8.5 δ18O + 18.02 (r2 = 0.97, n = 198). The isotope ratios in precipitation exhibited an enriched trend during the dry season and a notable depletion at the beginning of the wet season. The δ18O compositions in groundwater (average = −6.4‰, σ = 0.7) and stream water (average = −6.7‰, σ = 0.6) were relatively stable over time, and both components exhibited more enriched values in 2013, which was the drier year. No strong correlation was observed between the isotope ratios and the precipitation amount at the event or daily time‐step, but a correlation was observed on a monthly scale. Stream water and base flow hydrograph separations based on isotope end‐member estimations showed that pre‐event water originating from base flow was prevalent. However, isotope data indicate that event water originating from springs appears to have been the primary driver of initial rises in stream flow and peak flows. These results indicate that isotope sampling improves the understanding of water balance components, even in a tropical humid location, where significant variations in rainfall challenge current modelling efforts. Further research using fine‐scale hydrometric and isotopic data would enhance understanding the processes driving spring flow generation in watersheds.
Evaluating the functionality and streamflow impacts of explicitly modelling forest–snow interactions and canopy gaps in a distributed hydrologic model
Authors: Sun Ning , Wigmosta Mark , Zhou Tian , Lundquist Jessica , Dickerson‐Lange Susan , Cristea Nicoleta 
Published: May 2018

AbstractMany plot‐scale studies have shown that snow‐cover dynamics in forest gaps are distinctly different from those in open and continuously forested areas, and forest gaps have the potential to alter the magnitude and timing of snowmelt. However, the watershed‐level impacts of canopy gap treatment on streamflows are largely unknown. Here, we present the first research that explicitly assesses the impact of canopy gaps on seasonal streamflows and particularly late‐season low flows at the watershed scale. To explicitly model forest–snow interactions in canopy gaps, we made major enhancements to a widely used distributed hydrologic model, distributed hydrology soil vegetation model, with a canopy gap component that represents physical processes of snowpack evolution in the forest gap separately from the surrounding forest on the subgrid scale (within a grid typically 10–150 m). The model predicted snow water equivalent using the enhanced distributed hydrology soil vegetation model showed good agreement (R2 > 0.9) with subhourly snow water equivalent measurements collected from open, forested, and canopy gap sites in Idaho, USA. Compared with the original model that does not account for interactions between gaps and surrounding forest, the enhanced model predicted notably later melt in small‐ to medium‐size canopy gaps (the ratio of gap radius (r) to canopy height (h) ≤ 1.2), and snow melt rates exhibited great sensitivity to changing gap size in medium‐size gaps (0.5 ≤ r/h ≤ 1.2). We demonstrated the watershed‐scale implications of canopy gaps on streamflow in the snow‐dominated Chiwawa watershed, WA, USA. With 24% of the watershed drainage area (about 446 km2) converted to gaps of 60 m diameter, the mean annual 7‐day low flow was increased by 19.4% (i.e., 0.37 m3/s), and the mean monthly 7‐day low flows were increased by 13.5% (i.e., 0.26 m3/s) to 40% (i.e., 1.76 m3/s) from late summer through fall. Lastly, in practical implementation of canopy gaps with the same total gap areas, a greater number of distributed small gaps can have greater potential for longer snow retention than a smaller number of large gaps.
Factors controlling seasonal groundwater and solute flux from snow‐dominated basins
Authors: Carroll Rosemary W. H. , Bearup Lindsay A. , Brown Wendy , Dong Wenming , Bill Markus , Willlams Kenneth H. 
Published: May 2018

AbstractCritical zone influences on hydrologic partitioning, subsurface flow paths and reactions along these flow paths dictate the timing and magnitude of groundwater and solute flux to streams. To isolate first‐order controls on seasonal streamflow generation within highly heterogeneous, snow‐dominated basins of the Colorado River, we employ a multivariate statistical approach of end‐member mixing analysis using a suite of daily chemical and isotopic observations. Mixing models are developed across 11 nested basins (0.4 to 85 km2) spanning a gradient of climatological, physical, and geological characteristics. Hydrograph separation using rain, snow, and groundwater as end‐members indicates that seasonal contributions of groundwater to streams is significant. Mean annual groundwater flux ranges from 12% to 33% whereas maximum groundwater contributions of 17% to 50% occur during baseflow. The direct relationship between snow water equivalent and groundwater flux to streams is scale dependent with a trend toward self‐similarity when basins exceed 5.5 km2. We find groundwater recharge increases in basins of high relief and within the upper subalpine where maximum snow accumulation is coincident with reduced conifer cover and lower canopy densities. The mixing model developed for the furthest downstream site did not transfer to upstream basins. The resulting error in predicted stream concentrations points toward weathering reactions as a function of source rock and seasonal shifts in flow path. Additionally, the potential for microbial sulfate reduction in floodplain sediments along a low‐gradient, meandering portion of the river is sufficient to modify hillslope contributions and alter mixing ratios in the analysis. Soil flushing in response to snowmelt is not included as an end‐member but is identified as an important mechanism for release of solutes from these mountainous watersheds. End‐member mixing analysis used in combination with high‐frequency observations reveals important aspects of catchment hydrodynamics across scale.
Bulk density effects on soil hydrologic and thermal characteristics: A numerical investigation
Authors: Kojima Yuki , Heitman Joshua L. , Sakai Masaru , Kato Chihiro , Horton Robert 
Published: May 2018

AbstractSoil bulk density (ρb) is commonly treated as static in studies of land surface dynamics. Magnitudes of errors associated with this assumption are largely unknown. Our objectives were to (a) quantify ρb effects on soil hydrologic and thermal properties and (b) evaluate effects of ρb on surface energy balance and heat and water transfer. We evaluated 6 soil properties, volumetric heat capacity, thermal conductivity, soil thermal diffusivity, water retention characteristics, hydraulic conductivity, and vapour diffusivity, over a range of ρb, using a combination of 6 models. Thermal conductivity, water retention, hydraulic conductivity, and vapour diffusivity were most sensitive to ρb, each changing by fractions greater than the associated fractional changes in ρb. A 10% change in ρb led to 10–11% change in thermal conductivity, 6–11% change in saturated and residual water content, 49–54% change in saturated hydraulic conductivity, and 80% change in vapour diffusivity. Subsequently, 3 field seasons were simulated with a numerical model (HYDRUS‐1D) for a range of ρb values. When ρb increased 25% (from 1.2 to 1.5 Mg m−3), soil temperature variation decreased by 2.1 °C in shallow layers and increased by 1 °C in subsurface layers. Surface water content differed by 0.02 m3 m−3 for various ρb values during drying events but differences mostly disappeared in the subsurface. Matric potential varied by >100 m of water. Surface energy balance showed clear trends with ρb. Latent heat flux decreased 6%, sensible heat flux increased 9%, and magnitude of ground heat flux varied by 18% (with a 25% ρb increase). Transient ρb impacted surface conditions and fluxes, and clearly, it warrants consideration in field and modelling investigations.
miR‐130 aggravates acute myocardial infarction‐induced myocardial injury by targeting PPAR‐γ
Authors: Chu Xianglin , Wang Yiqing , Pang Liewen , Huang Jiechun , Sun Xiaotian , Chen Xiaofeng 
Published: May 2018

AbstractCardiac remodeling is a common pathophysiological change associated with acute myocardial infarction (AMI). Recent evidence indicates that microRNAs are strong posttranscriptional regulators which play an important role in regulating the microenvironment of myocardial tissue after AMI. In this study, we sought to explore the potential role and underlying mechanism of miR‐130 in AMI. H9c2 cells were cultured under hypoxic conditions to simulate myocardial infarction. The influence of aberrantly expressed miR‐130 on H9c2 cells under hypoxia was also estimated with RT‐PCR, western blot and enzyme‐linked immunosorbent assay. Using bioinformatics methods, of miR‐130 target genes were verified with luciferase reporter assay. Then, the effects of miR‐130 on AMI were identified in an induced myocardial injury model in rats. The results show that miR‐130 downregulation remarkably decreased hypoxia‐induced inflammation and fibrosis related protein expression in H9c2 cells and reversed hypoxia‐induced peroxisome proliferator‐activated receptor γ (PPAR‐γ) inhibition. A bifluorescein reporter assay further confirmed that PPAR‐γ was a target gene of miR‐130. This study verified that PPAR‐γ has a cardioprotective effect by inhibiting NFκB‐mediated inflammation and TGF‐β1‐mediated fibrosis. In vivo experiments confirmed that downregulation of miR‐130 expression promotes PPAR‐γ‐mediated cardioprotective effects by suppressing inflammation and myocardial fibrosis. Taken together, these findings suggest that miR‐130 knockdown alleviates infarction‐induced myocardial injury by promoting PPAR‐γ expression.
Decreased hepatic response to glucagon, adrenergic agonists, and cAMP in glycogenolysis, gluconeogenesis, and glycolysis in tumor‐bearing rats
Authors: Biazi Giuliana R. , Frasson Isabele G. , Miksza Daniele R. , de Morais Hely , de Fatima Silva Flaviane , Bertolini Gisele L. , de Souza Helenir M. 
Published: May 2018

AbstractThe response to glucagon and adrenaline in cancer cachexia is poorly known. The aim of this study was to investigate the response to glucagon, adrenergic agonists (α and β) and cyclic adenosine monophosphate (cAMP) on glycogenolysis, gluconeogenesis, and glycolysis in liver perfusion of Walker‐256 tumor‐bearing rats with advanced cachexia. Liver ATP content was also investigated. Rats without tumor (healthy) were used as controls. Agonists α (phenylephrine) and β (isoproterenol) adrenergic, instead of adrenaline, and cAMP, the second messenger of glucagon and isoproterenol, were used in an attempt to identify mechanisms involved in the responses. Glucagon (1 nM) stimulated glycogenolysis and gluconeogenesis and inhibited glycolysis in the liver of healthy and tumor‐bearing rats, but their effects were lower in tumor‐bearing rats. Isoproterenol (20 µM) stimulated glycogenolysis, gluconeogenesis, and glycolysis in healthy rats and had virtually no effect in tumor‐bearing rats. cAMP (9 µM) also stimulated glycogenolysis and gluconeogenesis and inhibited glycolysis in healthy rats but had practically no effect in tumor‐bearing rats. Phenylephrine (2 µM) stimulated glycogenolysis and gluconeogenesis and inhibited glycolysis and these effects were also lower in tumor‐bearing rats than in healthy. Liver ATP content was lower in tumor‐bearing rats. In conclusion, tumor‐bearing rats with advanced cachexia showed a decreased hepatic response to glucagon, adrenergic agonists (α and β), and cAMP in glycogenolysis, gluconeogenesis, and glycolysis, which may be due to a reduced rate of regulatory enzyme phosphorylation caused by the low ATP levels in the liver.
Fenofibrate improves renal function by amelioration of NOX‐4, IL‐18, and p53 expression in an experimental model of diabetic nephropathy
Authors: Yaribeygi Habib , Mohammadi Mohammad T. , Rezaee Ramin , Sahebkar Amirhossein 
Published: May 2018

AbstractAmong several pathological mechanisms involved in diabetic nephropathy, oxidative stress, inflammation, and apoptosis play a prominent role. Fenofibrate, a peroxisome proliferator‐activated receptor‐α (PPAR‐α) agonist, has markedly improved oxidative stress and inflammatory responses, but there is no evidence about its effects on interleukin‐18 (IL‐18), NADPH oxidase type 4 (NOX‐4), and p53 expression in diabetic kidneys. The aim of this study was to evaluate possible effects of fenofibrate on improving the underlying mechanisms of diabetic nephropathy. Male Wistar rats were randomly divided into four groups namely, normal, normal treated, diabetic and diabetic treated (N = 6). Diabetes was induced by a single dose of streptozotocin (40 mg/kg; IV). Treated animals received fenofibrate for 8 weeks daily (80 mg/kg; po). All groups were sacrificed on day 56 and blood, urine, and tissue samples were collected. Serum levels of urea, uric acid, creatinine, and glucose were assessed. Then, serum levels of malondialdehyde (MDA), nitrate, and glutathione (GLT), as well as the activities of catalase (CAT) and superoxide dismutase (SOD) enzymes were measured. The expression level of NOX‐4, IL‐18, and p53 proteins at both mRNA and protein levels were evaluated. Diabetes significantly increased albuminuria, free radicals production, inflammation, and apoptosis in non‐treated rats while lowered antioxidant capacity. Moreover, diabetes caused histological damages leading to renal failure. Treatment with fenofibrate improved renal function by improving creatinine clearance (P = 0.01) and protein excretion (P = 0.001) and lowering plasma levels of blood urea nitrogen (P = 0.001), creatinine (P = 0.001), and uric acid (P = 0.01). Fenofibrate potentiated antioxidant defense systems by enhancing CAT (P = 0.01) and SOD (P = 0.01) enzymes activities and GLT content (P = 0.01), and reduced oxidative damage by lowering MDA generation (P = 0.02). Fenofibrate also attenuated the expression of NOX‐4 (P = 0.05), IL‐18 (P = 0.05), and p53 (P = 0.05) at both mRNA and protein levels. In conclusion, treatment with fenofibrate improved renal function by suppression of oxidative stress, attenuation of inflammation, and inhibition of apoptosis.
Comparison between capillary zone electrophoresis and capillary isoelectric focusing for thalassemia screening in southern China
Authors: Lu Feng , Dai Qingkai , Zhang Xia , Zhou Wenjie , Gao Ju , Zhang Ge 
Published: May 2018

BackgroundCapillary isoelectric focusing is a type of capillary electrophoresis method newly used for thalassemia screening in China. Although the good performance has been proved by several studies, whether it can best suit the special needs of Chinese patients still requires further investigations.MethodsComparisons were made between capillary zone electrophoresis method applied on Sebia Minicap and capillary isoelectric focusing method applied on Helena V8 platform E‐class on identifying Hb E, Hb CS, Hb H, and Hb Barts for patients from southern China. And mixing studies were used to evaluate the lowest detection limits of these 2 kinds of capillary electrophoresis system.ResultsHelena V8 could not make a distinction between peaks of Hb E and peaks of Hb A2 as Sebia Minicap did. All chosen patients with Hb H and/or Hb Barts could be screened out by both 2 systems, but when analyzed by Helena V8, it was hard to distinguish Hb H from Hb Barts sometimes, while Sebia Minicap could make a clear distinction between peaks of Hb H and Hb Barts. Only a part of patients (3 of 8, 37.5%) with Hb CS could be screened out by Helena V8, while all patients could be identified by Sebia Minicap. Sebia Minicap had a lower detection limit for trace peaks than Helena V8 (near to 0.2% vs near to 0.6%).ConclusionsCompared with capillary zone electrophoresis, capillary isoelectric focusing applied on Helena V8 maybe is not the first choice for hemoglobinopathy testing in southern China.
Population Pharmacokinetics of Vancomycin in Patients Undergoing Allogeneic Hematopoietic Stem‐Cell Transplantation
Authors: Okada Akira , Kariya Misato , Irie Kei , Okada Yutaka , Hiramoto Nobuhiro , Hashimoto Hisako , Kajioka Ryosuke , Maruyama Chika , Kasai Hidefumi , Hamori Mami , Nishimura Asako , Shibata Nobuhito , Fukushima Keizo , Sugioka Nobuyuki 
Published: May 2018

AbstractVancomycin is a commonly used antimicrobial agent for patients undergoing allogeneic hematopoietic stem‐cell transplantation (allo‐HSCT). Vancomycin has large inter‐ and intraindividual pharmacokinetic variability, which is mainly described by renal function; various studies have indicated that vancomycin pharmacokinetics are altered in special populations. However, little is known regarding vancomycin pharmacokinetics in patients undergoing allo‐HSCT. Therefore, we aimed to develop a population pharmacokinetic (PopPK) model of vancomycin in patients undergoing allo‐HSCT for effective and safe antimicrobial therapy and to develop a vancomycin dosing nomogram for a vancomycin optimal‐dosing strategy. In total, 285 observations from 95 patients undergoing allo‐HSCT were available. The final PopPK parameter estimates were central volume of distribution (V1, L), 39.2; clearance (L/h), 4.25; peripheral volume of distribution (V2, L), 56.1; and intercompartmental clearance (L/h), 1.95. The developed vancomycin model revealed an increase in V1 and V2 compared with those in the general population that consisted of patients with methicillin‐resistant Staphylococcus aureus. Moreover, serum creatinine was reduced because of an increase in the plasma fraction because of destruction of hematopoietic stem cells accompanying allo‐HSCT pretreatment, suggesting that the Cockcroft–Gault equation–based creatinine clearance value was overestimated. To our knowledge, this is the first PopPK study to develop a dosing nomogram for vancomycin in patients undergoing allo‐HSCT and was proven to be useful in optimizing the dosage and dosing interval of vancomycin in these patients. This strategy will provide more useful information for vancomycin therapy with an evidence‐based dose adjustment.
Biofilm and planktonic population distribution. Key aspects in carbonaceous anodes for microbial fuel cells
Authors: Mateo Sara , Cañizares Pablo , Rodrigo Manuel Andrés , Fernandez‐Morales Francisco Jesus 
Published: May 2018

AbstractBACKGROUNDA comparison between different carbon‐based anodes used in microbial fuel cells (MFCs) has been carried out. Five different carbonaceous anodes were studied: carbon paper, carbon cloth, carbon foam 30 ppi, carbon foam 80 ppi and carbon felt.RESULTSThe current density generated was higher for the MFCs with porous anodes compared with the flat ones, generating up to 14.5 A m−2. However, when the superficial surface was higher than 7500 m2 m−2 the performance did not increase further due to microorganisms transport and mass transfer limitations. Regarding the biochemical performance, a linear relationship between the generated current density and the coulombic efficiency was found. This relationship indicates selection of the electrogenic microbial population when the superficial surface increases. From Illumina MiSeq analyses, it was observed that Shewanella population in the biofilm was c. 14%, while its population was negligible in the planktonic culture. This population distribution can be explained by the low growth rate of the Shewanella.CONCLUSIONSThese results demonstrate that the main driving force of the carbonaceous materials performance is the ease of biofilm formation and subsequent population selection, but not on specific electronic properties of the carbon materials. © 2018 Society of Chemical Industry
Firm Specific, Financial Development and Macroeconomic Determinants of Credit Union Lending
Authors: Amoah Benjamin , Aboagye Anthony Q.Q. , Bokpin Godfred A. , Ohene‐Asare Kwaku 
Published: May 2018

AbstractCredit unions are set up to provide financial services, especially loans to members in a cooperative setting. The increasing competition from banking and non‐banking financial institutions implies credit unions must provide financial products and services with a clear understanding of factors that interact in this competitive industry. This paper evaluates the discretional and non‐discretional factors that tend to influence loans credit unions grant their members. From fixed effect model estimate, discretional factors such as size, profitability, management quality and solvency positively associate with credit union loan business whiles loan loss, net worth, non‐loan income and non‐loan activities associate negatively. Contractionary monetary policy creates an increase in loan demand in the credit union. Credit union managers should monitor developments taking place in the loanable funds market as increasing overhead cost of banks may imply a possible increase in loan demand leading to diseconomies of scale. Copyright © 2018 John Wiley & Sons, Ltd.
Pigmentation and vision: Is GPR143 in control?
Authors: McKay Brian S. 
Published: May 2018

AbstractAlbinism, typically characterized by decreased melanin synthesis, is associated with significant visual deficits owing to developmental changes during neurosensory retina development. All albinism is caused by genetic mutations in a group of diverse genes including enzymes, transporters, G‐protein coupled receptor. Interestingly, these genes are not expressed in the neurosensory retina. Further, regardless of cause of albinism, all forms of albinism have the same retinal pathology, the extent of which is variable. In this review, we explore the possibility that this similarity in retinal phenotype is because all forms of albinism funnel through the same final common pathway. There are currently seven known genes linked to the seven forms of ocular cutaneous albinism. These types of albinism are the most common, and result in changes to all pigmented tissues (hair, skin, eyes). We will discuss the incidence and mechanism, where known, to develop a picture as to how the mutations cause albinism. Next, we will examine the one form of albinism which causes tissue‐specific pathology, ocular albinism, where the eye exhibits the retinal albinism phenotype despite near normal melanin synthesis. We will discuss a potential way to treat the disease and restore normal retinal development. Finally, we will briefly discuss the possibility that this same pathway may intersect with the most common cause of permanent vision loss in the elderly.