bluuebunny/crossref_metadata_2025_split huggingface dataset:
A study of the attitude of Latin‐American residents in Spain toward organ xenotransplantation
Authors: Ríos Antonio , López‐Navas Ana Isabel , Martínez‐Alarcón Laura , Sánchez José , Ramis Guillermo , Ramírez Pablo , Parrilla Pascual 
Published: December 2013

AbstractBackgroundIt is important to find out what would be the level of acceptance of xenotransplantation in society, especially in populations where there are preclinical trials. The Latin‐American population is growing in Spain, given the cultural, religious, and language similarities. Objectives: (i) to analyze attitude toward xenotransplantation in the population born in Latin America and now residing in Spain; and (ii) to establish the variables that affect this attitude.MethodA sample of Latin‐American residents in Spain was obtained randomly in 2010 and stratified by the respondent's nationality (n = 1.314). Attitude was evaluated using a validated questionnaire (PCID—XenoTx Rios), which was completed anonymously and self‐administered. Statistical analysis: Student's t‐test, the Chi‐squared test, Fisher's exact test, and logistic regression analysis.ResultsThe questionnaire completion rate was 89% (n = 1.165). If it was assumed that xenotransplanted organs functioned as well as human ones, 40% were in favor, 19% against, and 41% undecided. This attitude is related to: age (P = 0.003); sex (P = 0.002); level of education (P < 0.001); descendents (P = 0.003); country of origin (P < 0.001); participation in voluntary prosocial activities (P = 0.006); having spoken about donation and transplantation within the family (P < 0.001); a partner's favorable attitude toward transplantation (P < 0.001); previous experience of donation and/or transplantation (P < 0.001); a belief that one might need a transplant in the future (P < 0.001); and a favorable attitude toward human donation, both deceased as well as living (P < 0.001). In the multivariate analysis, the following variables continue to feature as independent variables: age (older: Odds Ratio = 1.041); sex (male: OR = 1.579); level of education (university: OR = 2.770); descendents (none: OR = 2.386); a partner's attitude toward transplantation (favorable: OR = 2.262); attitude toward deceased organ donation (favorable: OR = 1.587); previous experience of donation and/or transplantation (OR = 1.519); a belief that one might need a transplant in the future (OR = 1.675); and attitude toward related living donation (in favor: OR = 4.405).ConclusionsLatin Americans who usually reside in Spain have a more negative attitude toward xenotransplantation than the native Spanish population, and their attitude is affected by many psychosocial factors, mainly related to previous attitude toward the different types of human organ donation.
Statistical Downscaling of Daily Wind Speed Variations
Authors: Kirchmeier Megan C. , Lorenz David J. , Vimont Daniel J. 
Published: December 2013

AbstractThis study presents the development of a method to statistically downscale daily wind speed variations in an extended Great Lakes region. A probabilistic approach is used, predicting a daily-varying probability density function (PDF) of local-scale daily wind speed conditioned on large-scale daily wind speed predictors. Advantages of a probabilistic method are that it provides realistic information on the variance and extremes in addition to information on the mean, it allows the autocorrelation of downscaled realizations to be tuned to match the autocorrelation of local-scale observations, and it allows flexibility in the use of the final downscaled product. Much attention is given to fitting the proper functional form of the PDF by investigating the observed local-scale wind speed distribution (predictand) as a function of the decile of the large-scale wind (predictor). It is found that the local-scale standard deviation and the local-scale shape parameter (from a gamma distribution) are nonconstant functions of the large-scale predictor. As such, a vector generalized linear model is developed to relate the large-scale and local-scale wind speeds. Maximum likelihood and cross validation are used to fit local-scale gamma distribution shape and scale parameters to the large-scale wind speed. The result is a daily-varying probability distribution of local-scale wind speed, conditioned on the large-scale wind speed.
Synergy of antibacterial and antioxidant activities from crude extracts and peptides of selected plant mixture
Authors: Shami Abdul-Mushin M , Philip Koshy , Muniandy Sekaran 
Published: December 2013

AbstractBackgroundA plant mixture containing indigenous Australian plants was examined for synergistic antimicrobial activity using selected test microorganisms. This study aims to investigate antibacterial activities, antioxidant potential and the content of phenolic compounds in aqueous, ethanolic and peptide extracts of plant mixture.MethodsWell diffusion, minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) assays were used to test antibacterial activity against four pathogenic bacteria namelyStaphylococcus aureus, Escherichia coli, Bacillus cereus,andPseudomonas aeruginosa. DPPH (2, 2-diphenyl-1- picrylhydrazyl) and superoxide dismutase (SOD) assays were used to evaluate antioxidant activity. HPLC and gel filtration were used for purification of the peptides. Scanning electron microscope was applied to investigate the mode of attachment of the peptides on target microbial membranes.ResultsAqueous extraction of the mixture showed no inhibition zones against all the test bacteria. Mean diameter of inhibition zones for ethanol extraction of this mixture attained 8.33 mm, 7.33 mm, and 6.33 mm againstS. aureusat corresponding concentrations of 500, 250 and 125 mg/ml whileE .colishowed inhibition zones of 9.33 mm, 8.00 mm and 6.66 mm at the same concentrations.B. cereusexhibited inhibition zones of 11.33 mm, 10.33 mm and 10.00 mm at concentrations of 500, 250 and 125 mg/ml respectively. The peptide extract demonstrated antibacterial activity againstS. aureus,E. coliandB. cereus. The MIC and MBC values for ethanol extracts were determined at 125 mg/ml concentration againstS. aureusandE. coliandB. cereusvalue was 31.5 mg/ml. MIC and MBC values showed that the peptide extract was significantly effective at low concentration of the Australian plant mixture (APM). Phenolic compounds were detected in hot aqueous and ethanolic extracts of the plant mixture. Hot aqueous, ethanol and peptides extracts also exhibited antioxidant activities.ConclusionsIt was concluded that APM possessed good antibacterial and antioxidant activities following extraction with different solvents. The results suggest that APM provide a new source with antibacterial agents and antioxidant activity for nutraceutical or medical applications.
An efficient immunodetection method for histone modifications in plants
Authors: Nic-Can Geovanny , Hernández-Castellano Sara , Kú-González Angela , Loyola-Vargas Víctor M , De-la-Peña Clelia 
Published: December 2013

Abstract

Background
Epigenetic mechanisms can be highly dynamic, but the cross-talk among them and with the genome is still poorly understood. Many of these mechanisms work at different places in the cell and at different times of organism development. Covalent histone modifications are one of the most complex and studied epigenetic mechanisms involved in cellular reprogramming and development in plants. Therefore, the knowledge of the spatial distribution of histone methylation in different tissues is important to understand their behavior on specific cells.

Results
Based on the importance of epigenetic marks for biology, we present a simplified, inexpensive and efficient protocol for in situ immunolocalization on different tissues such as flowers, buds, callus, somatic embryo and meristematic tissue from several plants of agronomical and biological importance. Here, we fully describe all the steps to perform the localization of histone modifications. Using this method, we were able to visualize the distribution of H3K4me3 and H3K9me2 without loss of histological integrity of tissues from several plants, including Agave tequilana, Capsicum chinense, Coffea canephora and Cedrela odorata, as well as Arabidopsis thaliana.

Conclusions
There are many protocols to study chromatin modifications; however, most of them are expensive, difficult and require sophisticated equipment. Here, we provide an efficient protocol for in situ localization of histone methylation that dispenses with the use of expensive and sensitive enzymes. The present method can be used to investigate the cellular distribution and localization of a wide array of proteins, which could help to clarify the biological role that they play at specific times and places in different tissues of various plant species.
Pulsed addition of HMF and furfural to batch-grown xylose-utilizing Saccharomyces cerevisiaeresults in different physiological responses in glucose and xylose consumption phase
Authors: Ask Magnus , Bettiga Maurizio , Duraiswamy Varuni Raju , Olsson Lisbeth 
Published: December 2013

Abstract

Background
Pretreatment of lignocellulosic biomass generates a number of undesired degradation products that can inhibit microbial metabolism. Two of these compounds, the furan aldehydes 5-hydroxymethylfurfural (HMF) and 2-furaldehyde (furfural), have been shown to be an impediment for viable ethanol production. In the present study, HMF and furfural were pulse-added during either the glucose or the xylose consumption phase in order to dissect the effects of these inhibitors on energy state, redox metabolism, and gene expression of xylose-consuming Saccharomyces cerevisiae.

Results
Pulsed addition of 3.9 g L-1 HMF and 1.2 g L-1 furfural during either the glucose or the xylose consumption phase resulted in distinct physiological responses. Addition of furan aldehydes in the glucose consumption phase was followed by a decrease in the specific growth rate and the glycerol yield, whereas the acetate yield increased 7.3-fold, suggesting that NAD(P)H for furan aldehyde conversion was generated by acetate synthesis. No change in the intracellular levels of NAD(P)H was observed 1 hour after pulsing, whereas the intracellular concentration of ATP increased by 58%. An investigation of the response at transcriptional level revealed changes known to be correlated with perturbations in the specific growth rate, such as protein and nucleotide biosynthesis. Addition of furan aldehydes during the xylose consumption phase brought about an increase in the glycerol and acetate yields, whereas the xylitol yield was severely reduced. The intracellular concentrations of NADH and NADPH decreased by 58 and 85%, respectively, hence suggesting that HMF and furfural drained the cells of reducing power. The intracellular concentration of ATP was reduced by 42% 1 hour after pulsing of inhibitors, suggesting that energy-requiring repair or maintenance processes were activated. Transcriptome profiling showed that NADPH-requiring processes such as amino acid biosynthesis and sulfate and nitrogen assimilation were induced 1 hour after pulsing.

Conclusions
The redox and energy metabolism were found to be more severely affected after pulsing of furan aldehydes during the xylose consumption phase than during glucose consumption. Conceivably, this discrepancy resulted from the low xylose utilization rate, hence suggesting that xylose metabolism is a feasible target for metabolic engineering of more robust xylose-utilizing yeast strains.
Study on Hyperuricemia in HBV-Associated Glomerulonephritis
Authors: Zhuang Yongze , Yu Yinghao , Huang Yingfang , Zhong Xiaorong 
Published: December 2013

Abstract

Objectives:
To determine the prevalence and risk factors for hyperuricemia in hepatitis B virus–associated glomerulonephritis (HBV-GN).

Methods:
Univariate and multivariate logistic regression analysis was applied to decide the risk factors of hyperuricemia in HBV-GN, and clinical and pathologic data were compared between HBV-GN patients with hyperuricemia and those with normal serum uric acid.

Results:
Among our 227 HBV-GN cases, 31.3% of the patients had hyperuricemia at the time of renal biopsy. Univariate analysis showed that the level of serum creatinine and the severity of glomerular and tubular interstitial injury were significantly related to hyperuricemia. Multivariate logistic regression analysis identified the levels of serum creatinine and tubular interstitial injury as independent factors for hyperuricemia. The incidence of hypertension and lower estimated glomerular filtration rate was significantly higher in hyperuricemic patients with HBV-GN than in normouricemic patients. There were also fewer membranous nephropathy, more proliferative sclerosing glomerulonephritis, and more tubular interstitial injury in hyperuricemic patients with HBV-GN.

Conclusions:
Our study results suggest that hyperuricemia is common in HBV-GN, which may facilitate the progression of HBV-GN and renal tubular interstitial injury as well as the development of hypertension.
Clinical Value of Procalcitonin for Patients With Suspected Bloodstream Infection
Authors: Hattori Takuya , Nishiyama Hideki , Kato Hideki , Ikegami Shinobu , Nagayama Madoka , Asami Saori , Usami Miyuki , Suzuki Mayuko , Murakami Itsuka , Minoshima Makoto , Yamagishi Hiroe , Yuasa Norihiro 
Published: December 2013

Abstract

Objectives:
Procalcitonin (PCT) might be a useful marker to exclude bacteremia or to predict the severity of bacteremia and its outcome. However, most previous studies of PCT were limited to particular patient populations. In addition, reports about PCT levels in patients with renal dysfunction have been conflicting. We investigated the predictive value of PCT in an unselected population with suspected bloodstream infections and also assessed the relationship between PCT and renal function.

Methods:
We retrospectively analyzed medical records of 1,331 patients (age ≥1 8 years) with suspected bloodstream infections who had concurrent biochemical data and blood culture results.

Results:
The PCT level was significantly elevated in patients with positive blood cultures, and it showed a significant relation with survival in patients with bacteremia. The optimal cutoff value of PCT for predicting a positive blood culture showed an increase as the estimated glomerular filtration rate declined.

Conclusion:
PCT can be a useful marker to exclude bacteremia and also to predict severe bacteremia, but renal function should be taken into account.
Marrow Assessment for Hemophagocytic Lymphohistiocytosis Demonstrates Poor Correlation With Disease Probability
Authors: Ho Caleb , Yao Xiaopan , Tian Ligeng , Li Fang-Yong , Podoltsev Nikolai , Xu Mina L. 
Published: December 2013

Abstract

Objectives:
To evaluate the amount of hemophagocytosis in 64 marrow core biopsy specimens and aspirates from 58 patients with clinical suspicion for secondary hemophagocytic lymphohistiocytosis (HLH) or reported findings of hemophagocytosis.

Methods:
A review of medical records assigned patients to a low-risk (45 patients) or high-risk (13 patients) HLH group, and association with histologic findings was examined using the Fisher exact test.

Results:
The amount of hemophagocytosis in aspirate or the core biopsy specimen did not correlate with disease probability (P = .17 and P = .63, respectively). Of the clinical/laboratory criteria assessed, the most significant correlations with HLH were highly elevated ferritin (P = .01), cytopenias (P = .02), and fever (P = .009).

Conclusions:
Our findings indicated that marrow histologic findings alone do not reliably predict the probability of HLH, and an isolated finding of hemophagocytosis, even when present in a high amount, lacks specificity for HLH.
Graphene Oxide-Supported Two-Dimensional Microporous Polystyrene
Authors: Ouyang Yi , Wu Dingcai , Fu Ruowen 
Published: December 2013

ABSTRACTIn this paper, a microporous-containing graphene oxide/polystyrene (M-GO/PS) was designed and prepared by surface-initiated atom transfer radical polymerization (SI-ATRP) of PS from GO surface and then crossrlinking by carbon tetrachloride. The structures of the molecular brush of PS and the related crosslinking M-GO/PS were determined by FTIR, TG, SEM and nitrogen adsorption-desorption analysis. The experimental results showed that PS molecular brush were successfully grown on to the surface of GO. After crosslinking, the PS component was crosslinked into many round nanoparticles with a diameter of 20-30 nm, and therefore the specific surface area of GO/PS obviously increased. This kind of porous M-GO/PS composite was promising for the application in adsorption-desorption energy storage areas.
Discrete Gauge Fields for Graphene Membranes under Mechanical Strain
Authors: Sloan James V. , Pacheco Sanjuan Alejandro A. , Wang Zhengfei , Horvath Cedric M. , Barraza-Lopez Salvador 
Published: December 2013

ABSTRACTMechanical strain creates strong gauge fields in graphene, offering the possibility of controlling its electronic properties. We developed a gauge field theory on a honeycomb lattice valid beyond first-order continuum elasticity. Along the way, we resolve a recent controversy on the theory of strain engineering in graphene: there are no K-point dependent gauge fields.
Transparent Graphene-Platinum Films for Advancing the Performance of Dye-Sensitized Solar Cells
Authors: Shih P. T. , Dong R. X. , Ho K. C. , Lin J. J. 
Published: December 2013

ABSTRACTTransparent films of platinum nanoparticles on graphene nanohybrids were synthesized in a two-step process. Reduction of homogeneously dispersed Pt precursor and graphene in water and solution coating/annealing afforded thin films with high catalytic performance as counter electrodes in dye-sensitized solar cells (DSSC). The requisite dispersant consisting of poly(oxyethylene)-(POE) segments and cyclic imide functionalities allowed the in-situ reduction of dihydrogen hexachloroplatinate by ethanol and the formation of nanohybrids of graphene-supported Pt nanoparticles at 4.0 nm diameter. Characterizations of polymeric dispersants by Fourier-transform infrared spectroscopy, thermogravimetric analysis, and nanohybrids by transmission electron microscope were performed. After screening various compositions of Pt/graphene, the nanohybrid film at the specific ratio of 5/1 by weight was fabricated into a counter electrode (CE) for DSSC by the solution casting method. The evaluation of cell performance demonstrated the most improved power conversion efficiency of 8.00%. This is significant achievement in comparison with 7.14% for the DSSC with the conventional platinum sputtered CE. Furthermore, the solution casting method allows the preparation of transparent CE films that are suitable for using as rear-illuminated DSSC. The approach was proven to be feasible by measuring the cell efficiency under rear light illumination. The power efficiency up to 7.01%, comparable to 8.00% by a normally front illumination, has been accomplished. In contrast, the rear illumination at merely 2.36% efficiency was obtained for the DSSC with sputtered platinum CE. Analyses of cyclic voltammetry, electrochemical impedance spectra were well correlated to the high efficiency of the performance caused by this nanohybrid film.
Determining In-plane and Thru-plane Percolation Thresholds for Carbon Nanotube Thin Films Deposited on Paper Substrates Using Impedance Spectroscopy
Authors: Muhlbauer Rachel L. , Gerhardt Rosario A. 
Published: December 2013

ABSTRACTConcentration- and layer-dependent percolation thresholds can be determined for carbon nanotube (CNT) films deposited from aqueous dispersions on paper substrates at both the surface of the deposited film (in-plane) and through the thickness of the paper (thru-plane) using impedance spectroscopy. By analyzing the impedance spectra as a function of the number of layers (solution concentration is constant) or the solution concentration (number of layers is constant), the electrical properties and percolation thresholds for CNT-paper composites can be determined. In-plane measurements show that percolation occurs at 4 layers when 1 mg/mL solution concentration is used. In the thru-plane direction, the films are already percolated at 1 mg/mL concentration, which is confirmed by varying the concentration of the solution used to deposit 1 layer films. A second percolation event happens between 8 and 12 layers due to an increased number of interconnections of CNTs within the paper substrate. The lowest sheet resistance achieved was 100 Ω/□.
Field emission vacuum electronic devices utilizing ultrathin carbon nanotube sheet
Authors: Van Hai H. , Zhang Mei 
Published: December 2013

ABSTRACTNovel field emission (FE) devices are introduced employing lateral architecture. Ultrathin multiwalled carbon nanotube (MWCNT) sheet were utilized to fabricate the emitter. Effects of basic configuration of sheets, including the orientation of CNTs and sheet thickness were examined. The novel device achieved the threshold field (the electric field at which current density reach 1 mA/cm2) of 0.67 V/µm and enhancement factor larger than 20,000.
Mechanical Properties and Fracture Dynamics of Silicene Membranes
Authors: Botari Tiago , Perim Eric , Autreto P. A. S. , Paupitz Ricardo , Galvao Douglas S. 
Published: December 2013

ABSTRACTThe advent of graphene created a new era in materials science. Graphene is a two-dimensional planar honeycomb array of carbon atoms in sp2-hybridized states. A natural question is whether other elements of the IV-group of the periodic table (such as silicon and germanium), could also form graphene-like structures. Structurally, the silicon equivalent to graphene is called silicene. Silicene was theoretically predicted in 1994 and recently experimentally realized by different groups. Similarly to graphene, silicene exhibits electronic and mechanical properties that can be exploited to nanoelectronics applications.In this work we have investigated, through fully atomistic molecular dynamics (MD) simulations, the mechanical properties of single-layer silicene under mechanical strain. These simulations were carried out using a reactive force field (ReaxFF), as implemented in the LAMMPS code. We have calculated the elastic properties and the fracture patterns.Our results show that the dynamics of the whole fracturing processes of silicene present some similarities with that of graphene as well as some unique features.
Study and characterization of the carbon-based nanoparticles obtained from PET
Authors: Kharissova Alena Borisovna , de Casas Ortiz Edgar , Kharissova Oxana V. , Mendez Ubaldo Ortiz , Kharisov Boris I. 
Published: December 2013

ABSTRACTMaterial like PET {polyethylene terephthalate (C10H8O4)n} are usually thrown away present in glasses of refreshments, water bottles between others which are hard to be degraded. However, this material can be recycled and used to acquire nanostructures. During this investigation the objective was to obtain nanoparticles and carbon based nanostructures from the polymer type PET by means of microwave irradiation at the temperature of 260°C at normal pressure and at 600 psi in the presence of acids, ethylene glycol and by means of calcinations. The obtained nanoparticles of ultrananocrystalline diamonds were studied by means of scanning electron microscopy (SEM), high-resolution transmission electron microscopy (TEM), and Raman spectroscopy.
Coherent Control of an NV- center and a nearby 13C nuclear spin
Authors: Scharfenberger Burkhard , Munro William J. , Nemoto Kae 
Published: December 2013

ABSTRACTIn this work, we numerically investigated the achievable fidelities when controlling an effective three-qubit system consisting of a NV- color center in diamond with a nearby strongly coupled 13C nuclear spin by means of microwave- and radio-frequency pulses in the experimentally attractive low magnetic field regime. We find that gates with straightforward square driving pulses do not achieve the fidelity currently required for the fault-tolerant quantum computing models.