bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of isolated or combined exposure to sibutramine and rosuvastatin on reproductive parameters of adult male rats
Authors: e Silva Patrícia Villela , Borges Cibele dos Santos , Rosa Josiane de Lima , Pacheco Tainá Louise , Figueiredo Thamiris Moreira , Leite Gabriel Adan Araújo , Guerra Marina Trevizan , Anselmo‐Franci Janete Aparecida , Klinefelter Gary Robert , Kempinas Wilma De Grava 
Published: February 2020

AbstractMany obese patients are exposed to hypolipidemic and serotonin‐norepinephrine reuptake inhibitor (SNRI) drugs. Statins are one of the most marketed drugs in the world to treat dyslipidemia, while sibutramine, a SNRI drug, is prescribed in some countries to treat obesity and is detected as an additive in many adulterated weight loss supplements marketed worldwide. Previous studies reported adverse effects of isolated exposure to these drugs on male rat reproductive parameters. In the present work, we further investigated male reproductive toxicity of these drugs, administered in isolation or combination in adult rats for a longer period of treatment. Adult male rats (90 days) were treated (gavage) for 70 days with saline and dimethyl sulfoxide (control), sibutramine (10 mg/kg), rosuvastatin (5 mg/kg), or rosuvastatin combined with sibutramine. Sibutramine alone or with rosuvastatin, promoted a reduction in food intake and body weight gain, weight of the epididymis, ventral prostate and seminal vesicle; as well as decreased sperm reserves and transit time through the epididymis; androgen depletion; and increased index of cytoplasmic droplet. The rosuvastatin‐treated group showed reduced frequency of ejaculation. Exposure to this drug alone or combined with sibutramine impaired epididymal morphology. Co‐exposed rats had altered epididymal morphometry, and seminal vesicle and testis weights. The rats also showed decreased fertility after natural mating and a trend toward a delay in ejaculation, suggesting a small synergistic effect of these drugs. Given the greater reproductive efficiency of rodents, the results obtained in the present study raise concern regarding possible fertility impairment in men taking statins and SNRI drugs.
Cascade substitution reaction between oxabornene and amines to construct cyclohexa‐1,4‐diene‐3,6‐diamine and amino alcohol
Authors: Zhao Changkuo , Wang Xianheng , Xu Lang , Cao Ying , Cui Hanqi , Wang Yuhe 
Published: February 2020

AbstractIn competition with Michael addition between oxabornene and amines, a cascade substitution reaction predominates to generate cyclohexa‐1,4‐diene‐3,6‐diamine and amino alcohol in a moderate yield. This method has wide universality for different amines, overcomes the shortcomings of Michael addition reaction that cannot be synthesized due to shortage of raw materials, and can be further applied to the total synthesis of some related natural products.
Determination of HIV status and identification of incident HIV infections in a large, community‐randomized trial: HPTN 071 (PopART)
Authors: Eshleman Susan H , Piwowar‐Manning Estelle , Wilson Ethan A , Lennon Denni , Fogel Jessica M , Agyei Yaw , Sullivan Philip A , Weng Lei , Moore Ayana , Laeyendecker Oliver , Kosloff Barry , Bwalya Justin , Maarman Gerald , van Deventer Anneen , Floyd Sian , Bock Peter , Ayles Helen , Fidler Sarah , Hayes Richard , Donnell Deborah ,   for the HPTN 071 (PopART) Study Team
Published: February 2020

AbstractIntroductionThe HPTN 071 (PopART) trial evaluated the impact of an HIV combination prevention package that included “universal testing and treatment” on HIV incidence in 21 communities in Zambia and South Africa during 2013‐2018. The primary study endpoint was based on the results of laboratory‐based HIV testing for> 48,000 participants who were followed for up to three years. This report evaluated the performance of HIV assays and algorithms used to determine HIV status and identify incident HIV infections in HPTN 071, and assessed the impact of errors on HIV incidence estimates.MethodsHIV status was determined using a streamlined, algorithmic approach. A single HIV screening test was performed at centralized laboratories in Zambia and South Africa (all participants, all visits). Additional testing was performed at the HPTN Laboratory Center using antigen/antibody screening tests, a discriminatory test and an HIV RNA test. This testing was performed to investigate cases with discordant test results and confirm incident HIV infections.ResultsHIV testing identified 978 seroconverter cases. This included 28 cases where the participant had acute HIV infection at the first HIV‐positive visit. Investigations of cases with discordant test results identified cases where there was a participant or sample error (mixups). Seroreverter cases (errors where status changed from HIV infected to HIV uninfected, 0.4% of all cases) were excluded from the primary endpoint analysis. Statistical analysis demonstrated that exclusion of those cases improved the accuracy of HIV incidence estimates.ConclusionsThis report demonstrates that the streamlined, algorithmic approach effectively identified HIV infections in this large cluster‐randomized trial. Longitudinal HIV testing (all participants, all visits) and quality control testing provided useful data on the frequency of errors and provided more accurate data for HIV incidence estimates.
Longitudinal in vivo monitoring of callus remodeling in BMP‐7‐ and Zoledronate‐treated fractures
Authors: Mathavan Neashan , Raina Deepak Bushan , Tägil Magnus , Isaksson Hanna 
Published: February 2020

AbstractPharmacological interventions that combine pro‐anabolic and anti‐catabolic drugs to treat recalcitrant fractures have shown remarkable efficacy in augmenting the regenerative response. Specifically, in rodent models of fracture repair, treatment with BMP‐7 and Zoledronate (ZA) has almost uniformally resulted in complete union. However, delayed remodeling may be problematic for ZA‐treated fractures. The increase in newly formed bone is substantial but if translated in humans, delayed remodeling may delay functional recovery. Our objective was to determine if, and to what extent, bone morphogenetic protein (BMP) (in synergistically administered BMP‐7 + ZA) can modulate the delayed hard callus remodeling caused by ZA. Callus remodeling in BMP‐7‐only and BMP‐7 + ZA‐treated osteotomies were monitored using in vivo µCT to follow the progression of healing at 6‐week intervals over 24 weeks in an open femoral fracture rat model. None of the groups recovered baseline cortical bone volumes within 24 weeks post‐osteotomy. Treatment prolonged the remodeling phase but the kinetics of remodeling appeared to differ between BMP and BMP + ZA groups. However, the mechanical characteristics were largely restored. Callus/bone volumes in BMP‐only treated fractures peaked as early as week 3 suggesting that remodeling is stimulated prematurely. However, this rate of remodeling was not maintained as BMP‐7 was found to exhibit negligible changes in callus/bone volumes between weeks 6 and 18, whereas declines in callus/bone volumes were present at these time points in the BMP‐7 + ZA group. Our findings suggest that inclusion of ZA as an anti‐catabolic agent may not be detrimental to the regenerative process despite a prolonged remodeling phase.
Biosurfactants Production Using Permeate from Whey Ultrafiltration and Bioproduct Recovery by Membrane Separation Process
Authors: Decesaro Andressa , Machado Thaís Strieder , Cappellaro Ângela Carolina , Rempel Alan , Margarites Ana Cláudia , Reinehr Christian Oliveira , Eberlin Marcos Nogueira , Zampieri Davila , Thomé Antônio , Colla Luciane Maria 
Published: February 2020

AbstractThe management of whey is a challenge for dairy products where the volume produced is remarkable. This problem is minimized through membrane separation processes (MSP) to obtain whey protein concentrate, which has high added value. However, a permeate effluent stream is still generated that is composed of lactose, vitamins, and minerals, which can serve as raw material for the production of biotechnological compounds. Thus, this study aimed to produce biosurfactants using the permeate from whey ultrafiltration as part of the culture media of the bioprocess, to recover the biosurfactant produced using MSP, and to identify the biocompound. The production was carried out using Bacillus methylotrophicus and Bacillus pumilus. The variables nitrogen source (urea or ammonium sulfate), nitrogen source concentration (0.5% or 1.0%), inducer (soybean oil or biodiesel), inducer concentration (1% or 2%), and the addition of micronutrients (with our without) were studied using a fractional factorial experimental design 25‐1IV. In the fermentation processes, it was possible to verify the biosurfactant production through the reduction of surface tension, obtaining a minimum value of 35.07 mN/m for B. methylotrophicus and 26.02 mN/m for B. pumilus. Recovery via MSP was an efficient strategy for biosurfactant purification, which was concentrated in the fraction of the retentate. We produced a high‐value‐added biocompound identified as surfactin, valuing the permeate residue from whey ultrafiltration.
High‐throughput determination of fungicides in grapes using thin‐film microextraction coupled with liquid chromatography–tandem mass spectrometry
Authors: Zhang Zong‐hui , Zhao Hui‐yu , Shen Qian , Qi Pei‐pei , Wang Xin‐quan , Xu Hao , Di Shan‐shan , Wang Zhi‐wei 
Published: February 2020

AbstractA high‐throughput and environmentally friendly method based on 96‐well plate thin‐film microextraction was established to determine 14 fungicides in grapes and grape juice using liquid chromatography–tandem mass spectrometry. The thin‐film microextraction optimized method consisted of 60 min of extraction at pH 6.0 with the addition of sodium chloride (2–5%). Acetonitrile/water in the ratio of 8:2 was used for desorption analytes for 60 min. Evaluation of different extractive phases showed that polyacrylonitrile–polystyrene–divinylbenzene was the optimum coating. The linearity of the method was good in the range of 0.01–0.5 μg/mL for 14 fungicides with determination coefficients (R2) from 0.990 to 0.999, which indicated good linearity for both the grape juice and grape matrixes. The limit of detection was in the range of 0.002–0.01 μg/mL. The limit of quantitation was in the range of 0.01 mg/kg according to the minimum fortified level. The average absolute recoveries of the 14 fungicides ranged from 75.0 to 118.3%. The intraday relative standard deviation (n = 4) and interday relative standard deviation (n = 4) were 5.6–13.0% and 1.6–6.4%, respectively. This study showed that this method can be used for analyzing 96 samples in parallel, and the sample preparation time was approximately 2.0 min per sample. In addition, this approach offers a green and low‐cost sample pretreatment technique for future analyses.
Untargeted metabolomic study on the insomnia effect of Suan‐Zao‐Ren decoction in the rat serum and brain using ultra‐high‐performance liquid chromatography quadrupole time‐of‐flight mass spectrometry combined with data processing analysis
Authors: Du Yiyang , Wu Bo , Xiao Feng , Yan Tingxu , Li Qing , Jia Ying , Bi Kaishun , He Bosai 
Published: February 2020

AbstractInsomnia is a common clinical disease that can seriously damage the normal lives of sufferers. Suan‐Zao‐Ren decoction has been used to treat insomnia for a long time. However, the underlying molecular mechanism of Suan‐Zao‐Ren decoction is still not clear. In this study, the nontargeted metabolomics based on high‐resolution mass spectrometry and multiple statistical approaches were initially used to investigate the changes of potential serum and brain biomarkers and metabolic pathways in the insomnia model rat. Principal component analysis‐discriminate analysis indicated that the Suan‐Zao‐Ren decoction treatment improved the metabolic phenotype insomnia. Moreover, the heatmap analysis identified the most important biomarkers involved in insomnia. According to the pathway analysis, phenylalanine metabolism, tryptophan metabolism, and so on were recognized as the most affected metabolic pathways associated with insomnia disease. These findings provided a comprehensive understanding of the regulative effects of Suan‐Zao‐Ren decoction on the host metabolic phenotype of the insomnia rats. Our work demonstrated that the metabolomics approach is a promising tool that could help us to conduct the exploration of the therapeutic effects and mechanism of traditional Chinese medicines.
Freshening of the western Arctic negates anthropogenic carbon uptake potential
Authors: Woosley Ryan J. , Millero Frank J. 
Published: February 2020

AbstractAs human activities increase the atmospheric concentration of carbon dioxide (CO2), the oceans are known to absorb a significant portion. The Arctic Ocean has long been considered to have enormous potential to sequester anthropogenic CO2, and mitigate emissions. The frigid waters make CO2more soluble, and as sea ice melts, greater surface area is exposed to absorb CO2. However, sparse data have made quantifying the amount of anthropogenic CO2in the Arctic difficult, stimulating much debate over the basin's contribution to CO2sequestration from the atmosphere. Using three separate cruises in 1994, 2005, and 2015 in the Canada and Makarov basins, we analyze the decadal variability in anthropogenic CO2uptake in the central western Arctic. Here we show, from direct carbon system measurements spanning two decades, that despite increased atmospheric CO2, total dissolved inorganic carbon has actually decreased, with minimal anthropogenic CO2uptake. The reduction in dissolved CO2results from a dilution of total alkalinity by increased freshwater supply, particularly river water. Changes in the freshwater budget of the western Arctic override its uptake potential, resulting in a weak sink, or possibly source of CO2.
Role of tool pin profiles on wear characteristics of friction stir processed magnesium alloy ZK60/silicon carbide surface composites
Authors: Vignesh Kumar M. , Padmanaban G. , Balasubramanian V. 
Published: February 2020

AbstractPoor friction and wear resistance are the major drawbacks that restrict structural applications of ZK60 magnesium alloys. The surface properties of magnesium alloy can be enhanced by reinforcing particles in the surface using friction stir processing (FSP). Tool pin profile is the significant process parameters which influences the material flow, particle breakups and its distribution in the processed zone. In this study, an attempt was made in order to understand the major effects of tool pin profiles namely, cylindrical thread (CT), plain cylindrical (PC), plain tapered cylindrical (PTC) and square (SA) pin profiles on the microstructure characteristics and particle distribution of friction stir processed/silicon carbide particle surface composites. The surface composites fabricated by plain tapered cylindrical pin profile yield superior properties which is attributed to the higher shear force and balanced state of material flow and heat generation in the processed zone. The formation of smaller grains and hardness enhancement due to dispersion strengthening are the main causes to get better wear resistance of friction stir processed/silicon carbide particle magnesium alloy.
Triple‐wavelength Q‐switched ytterbium‐doped fiber laser based on tungsten oxide as saturable absorber
Authors: Salman Ali A. , Al‐Janabi Abdulhadi 
Published: February 2020

AbstractIn this article, a multiwavelength Q‐switched ytterbium‐doped fiber laser using tungsten oxide nanoparticles (WO3 NPs) as a saturable absorber (SA) is reported for the first time. The SA was prepared by depositing micron‐sized layers of WO3 NPs suspension onto the surface of the fiber tip via direct deposition process. After embedding the SA into an ytterbium‐doped fiber laser cavity, self‐starting Q‐switched performance was realized at a bleaching threshold of 179 mW having a minimum pulse width of 2.92 μs and maximum pulse energy of 9.26 nJ with variable repetition rates from 14.8 to 71.3 kHz. By boosting the pump power and proper adjustment of the polarization controller, steady dual‐ and triple‐wavelength operations were obtained at pump powers of 210 and 275 mW, respectively. The obtained results confirm the practical use of WO3 as an effective nonlinear modulator for multiwavelength and pulsed fiber lasers near 1 μm wavelength band.
Impact of angle of attack on plasma flow and electromagnetic wave propagation around hypersonic vehicles
Authors: Ouyang Wenchong , Liu Yanming , Zhang Xu 
Published: February 2020

AbstractThe flow field around the RAMC‐II vehicle at differenrt angles of attack (AOA) was numerically solved using a computational fluid dynamics technique with a three‐dimensional model. Electron density, pressure, temperature, and collision frequency, which is given great importance in this paper. The maximal electron density, total pressure, and temperature at the same position decreases with the angle of attack on the leeward side and increases with the angle of attack on the windward side. The collision frequency is almost unaffected by AOA on the leeward side, but increases significantly with AOA on the windward side. Based on the realistic plasma sheaths obtained by hypersonic fluid model, a multilayer transmission model was used to study the electromagnetic (EM) wave propagation in plasma sheath at different AOA. The attenuation value of EM wave on the leeward (windward) side decreases (increases) with the AOA. So the influence of the AOA on the EM wave transmission must be considered in the communication of vehicle reentry. In addition, the EM wave attenuation on the leeward at the same angle of attack is always smaller than the windward side, especially at a large AOA. Therefore, the leeward side can be considered as one end of the communication to improve the communication quality. The conclusions of this paper have both theoretical and practical significance to better understand the communication“blackout” problem for the reentry of hypersonic vehicles.
Improvement of unidirectional scattering characteristics based on multiple nanospheres array
Authors: Jiang Li , Fang Bo , Yan Zhigang , Li Chenxia , Fu Jipeng , Gan Haiyong , Hong Zhi , Jing Xufeng 
Published: February 2020

AbstractAll dielectric nanospheres with low loss and ultra‐compact characteristics can be effectively applied in nanophotonics in the visible and infrared ranges. The unidirectional forward scattering with azimuthally symmetry can be achieved by simple dielectric nanosphere. The physical origin of this directionality can be attributed to the interference effect of electric and magnetic resonances induced in nanoshperes. For the forward scattering of a single nanosphere the spectrally overlapping resonance of electric and magnetic quadrupoles can further enhance the directionality and magnitude of unidirectional forward scattering. For a nanosphere homodimers, the scattering pattern can also preserve the azimuthal asymmetry and the suppression of backscattering. But, the side scattering lobes occur due to the grating diffraction effect. Furthermore, the significant improvement of scattering magnitude and directionality can be achieved by a linear chain of nanospheres. These unique optical scattering of nanoshperes can be applied in the fields of nanoantennas, photovoltaics, and nanolasers in visible and near infrared ranges.
A mathematical expression for depth‐light curves of therapeutic proton beams in a quenching scintillator
Authors: Kelleter Laurent , Jolly Simon 
Published: February 2020

PurposeRecently, there has been increasing interest in the development of scintillator‐based detectors for the measurement of depth–dose curves of therapeutic proton beams (Beaulieu and Beddar [2016], Phys Med Biol., 61:R305–R343). These detectors allow the measurement of single beam parameters such as the proton range or the reconstruction of the full three‐dimensional dose distribution. Thus, scintillation detectors could play an important role in beam quality assurance, online beam monitoring, and proton imaging. However, the light output of the scintillator as a function of dose deposition is subject to quenching effects due to the high‐specific energy loss of incident protons, particularly in the Bragg peak. The aim of this work is to develop a model that describes the percent depth‐light curve in a quenching scintillator and allow the extraction of information about the beam range and the strength of the quenching.MethodsA mathematical expression of a depth‐light curve, derived from a combination of Birks’ law (Birks [1951], Proc Phys Soc A., 64:874) and Bortfeld’s Bragg curve (Bortfeld [1997], Med Phys., 24:2024–2033) that is termed a “quenched Bragg” curve, is presented. The model is validated against simulation and measurement.ResultsA fit of the quenched Bragg model to simulated depth‐light curves in a polystyrene‐based scintillator shows good agreement between the two, with a maximum deviation of 2.5% at the Bragg peak. The differences are larger behind the Bragg peak and in the dose build‐up region. In the same simulation, the difference between the reconstructed range and the reference proton range is found to be always smaller than 0.16 mm. The comparison with measured data shows that the fitted beam range agrees with the reference range within their respective uncertainties.ConclusionsThe quenched Bragg model is, therefore, an accurate tool for the range measurement from quenched depth–dose curves. Moreover, it allows the reconstruction of the beam energy spread, the particle fluence, and the magnitude of the quenching effect from a measured depth‐light curve.
Does the magnetization transfer effect bias chemical exchange saturation transfer effects? Quantifying chemical exchange saturation transfer in the presence of magnetization transfer
Authors: Smith Alex K. , Ray Kevin J. , Larkin James R. , Craig Martin , Smith Seth A. , Chappell Michael A. 
Published: February 2020

PurposeChemical exchange saturation transfer (CEST) is an MRI technique sensitive to the presence of low‐concentration solute protons exchanging with water. However, magnetization transfer (MT) effects also arise when large semisolid molecules interact with water, which biases CEST parameter estimates if quantitative models do not account for macromolecular effects. This study establishes under what conditions this bias is significant and demonstrates how using an appropriate model provides more accurate quantitative CEST measurements.MethodsCEST and MT data were acquired in phantoms containing bovine serum albumin and agarose. Several quantitative CEST and MT models were used with the phantom data to demonstrate how underfitting can influence estimates of the CEST effect. CEST and MT data were acquired in healthy volunteers, and a two‐pool model was fit in vivo and in vitro, whereas removing increasing amounts of CEST data to show biases in the CEST analysis also corrupts MT parameter estimates.ResultsWhen all significant CEST/MT effects were included, the derived parameter estimates for each CEST/MT pool significantly correlated (P < .05) with bovine serum albumin/agarose concentration; minimal or negative correlations were found with underfitted data. Additionally, a bootstrap analysis demonstrated that significant biases occur in MT parameter estimates (P < .001) when unmodeled CEST data are included in the analysis.ConclusionsThese results indicate that current practices of simultaneously fitting both CEST and MT effects in model‐based analyses can lead to significant bias in all parameter estimates unless a sufficiently detailed model is utilized. Therefore, care must be taken when quantifying CEST and MT effects in vivo by properly modeling data to minimize these biases.