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Energy distributions of multiple backscattered photons in materials

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Nuclear Science and Techniques 2018年第2期29卷 68-73页

作者： Asuman Ayd?n Department of Physics Faculty of Arts and SciencesBal?kesir UniversityCagis Campus

Backscattering of gamma photons from a material is of fundamental importance in radiation shielding,industrial and medical applications, radiation dosimetry,and non-destructive testing. In Compton scattering, incident photons undergo multiple scatterings within the material(target) before exiting. Gamma photons continue to soften in energy as the number of scatterings increases in a thick target; in other words, the energy of gamma photons decreases as the scatterings increase in case of a thick target and results in the generation of singly and multiply scattered events. In this work, the energy distribution of backscattered gamma photons with backscattering intensity and energy probabilities were calculated by using the Monte Carlo method for metallic, biological, and shielding materials with various thicknesses of slab geometry. The materials under study were targeted with gamma photons of 0.279, 0.662, 1.250, and 2.100 Me v energies. In addition, the energy distributions of multiply scattered gamma photons were studied for materials with infinite *** results are presented and discussed in detail by comparing with other Monte Carlo calculations.

关键词： Monte Carlo simulation Gamma photon Backscattering energy distribution Backscattering probability Compton scattering

Ectomycorrhizal and Saprotrophic Fungal Communities vary Across mm-Scale Soil Microsites Differing in Phosphatase Activity

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Pedosphere 2019年第3期29卷 344-359页

作者： Aaron GODIN Denise BROOKS Sue J. GRAYSTON Melanie D. JONES Biology Department University of British Columbia Okanagan campus Kelowna V1V 1V7 (Canada) Department of Forest & Conservation sciences Faculty of Forestry University of British Columbia Vancouver V6T 1Z4 (Canada)

To understand nutrient cycling in soils, soil processes and microorganisms need be better characterized. To determine whether specific trophic groups of fungi are associated with soil enzyme activity, we used soil imprinting to guide mm-scale sampling from microsites with high and low phosphatase activities in birch/Douglas-fir stands. Study 1 involved sampling one root window per site at 12 sites of different ages(stands);study 2 was conducted at one of the stem-exclusion stands, at which 5 root windows had been installed. Total fungal and ectomycorrhizal(EM) fungal terminal-restriction fragment length polymorphism(TRFLP)fingerprints differed between high-and low-phosphatase activity microsites at 8 of 12 root windows across 12 sites. Where differences were detected, fewer EM fungi were detected in high-than low-phosphatase activity microsites. Using 5 root windows at one site,next-generation sequencing detected similar fungal communities across microsites, but the ratio of saprotrophic to EM fungal reads was higher in high-phosphatase activity microsites in the two windows that had low EM fungal richness. In windows with differences in fungal communities, both studies indicated that EM fungi were less successful than saprotrophic fungi in colonizing fine-scale,organic matter-rich microsites. Fine-scale sampling linked with in situ detection of enzyme activity revealed relationships between soil fungal communities and phosphatase activity that could not be observed at the scales employed by conventional approaches, thereby contributing to the understanding of fine-scale phosphorus cycling in forest soils.

关键词： ectomycorrhizae fine scale fungal communities phosphatase root windows saprotrophic fungi soil imprinting

Phosalone-induced inflammation and oxidative stress in the colon: evaluation and treatment

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World Journal of Gastroenterology 2016年第21期22卷 4999-5011页

作者： Seyedeh Farnaz Ghasemi-Niri Faheem Maqbool Maryam Baeeri Mahdi Gholami Mohammad Abdollahi faculty of Pharmacy and Pharmaceutical Sciences Research Center Tehran University of Medical Sciences International campus Tehran University of Medical Sciences

AIM: To investigate the side effects of phosalone on intestinal cells and to evaluate benefits of ellagic acid(EA) as a ***: In order to conduct an in vivo study, a rat model was used. The rats were divided into ten groups based on the materials used in the experiment and their dosage. The first group was fed normally. The second group was administered EA through gavage. Next Four groups were given(1/3, 1/5, 1/10, 1/20) LD50 phosalone; an organophosphorus compound. The last four groups received(1/3, 1/5, 1/10, 1/20) LD50 phosalone and of EA. After one month, the rats were sacrificed and their colon cells were examined to evaluate the level of inflammation, proteins and oxidative stress ***: The results of this research show that phosalone elevates oxidative stress and changes the level of tumor necrosis factor-a(TNF-α), interlukin-6β(IL-6β) and nuclear factor(NF)-κB proteins. EA administration reduced phosalone toxicity and changed oxidative stress and inflammatory markers for all phosalone doses. Overall changes in reduction of TNF-α(230.47 ± 16.55 pg/mg protein vs 546.43 ± 45.24 pg/mg protein, P vs 21.55 ± 1.3 pg/mg protein, P vs 51.41 ± 0.71 pg/mg protein, P viable for 1/3 LD50 dose of phosalone. Furthermore, EA is effective to counteract the negative outcomes of oxidative stress. When EA was used to treat 1/3 LD50 of phosalone's side effects, it improved the level of ACh E activity(48.5% ± 6% vs 25% ± 7%, P vs 0.249 ± 0.032 mmol/L, P vs 18.22 ± 1.9 μmol/L, P vs 0.387 ± 0.04 U/mg protein, P ve to alleviate the side effects of phosalone by reducing the level of oxidative stress and inflammatory proteins.

关键词： Organophosphorus Phosalone Ellagic acid Inflammation Oxidative stress Colon

Unusual ovarian hyperstimulation syndrome presentation:Pleural effusion without ascites.A case report

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World Journal of Clinical Cases 2025年第8期13卷 26-34页

作者： Íngrid Solsona Sara Peralta Yasmina Barral Francisco Fàbregues Pepita Giménez-Bonafé Department of Physiological sciences Physiology UnitFaculty of Medicine and Health SciencesBellvitge CampusUniversitat de BarcelonaIDIBELLBarcelona 08907CataloniaSpain Institut Clinic of Gynecology Obstetrics and NeonatologyHospital ClínicInstitut d'Investigacions Biomèdiques August Pi i SunyerFaculty of MedicineUniversity of BarcelonaBarcelona 08036CataloniaSpain Department of Physiological sciences Faculty of Medicine and Health SciencesBellvitge CampusUniversitat de BarcelonaIDIBELLL'Hospitalet de Llobregat 08907BarcelonaSpain

BACKGROUND Ovarian hyperstimulation syndrome(OHSS)is a life-threatening complication that can occur in the luteal phase or early pregnancy after controlled ovarian *** case report highlights a unique manifestation of OHSS involving pleural effusion(PE)in a patient without identifiable risk *** SUMMARY A 39-year-old woman who underwent controlled ovarian hyperstimulation for an in vitro fertilization(IvF)cycle experienced dyspnea on the eleventh day of post oocyte *** diagnosis was severe OHSS with a unique manifestation of PE without *** management involved fluid balance and treatment with albumin,furosemide,thromboembolic prophylaxis,and thoracentesis.A continued drainage of the pleural cavity was *** patient had a favo-rable outcome,and a dichorionic diamniotic gestation passed without *** OHSS and its potential complications can include respiratory distress and PE,as well as thromboembolic disorders.

关键词： Dyspnea Infertility In vitro fertilization Ovarian hyperstimulation syndrome Pleural effusion Thoracentesis Case report

Effect of Gongronema latifolium on gastric emptying in healthy dogs

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World Journal of Gastroenterology 2013年第6期19卷 897-902页

作者： Sylvester O Ogbu Kenneth K Agwu Isaac U Asuzu Department of Medical Radiography and Radiological sciences Faculty of Health Sciences and TechnologyCollege of MedicineUniversity of Nigeria Enugu CampusEnugu State 400001Nigeria Department of veterinary Physiology and Pharmacology Faculty of Veterinary MedicineUniversity of Nigeria Nsukka CampusEnugu State 400001Nigeria

AIM:To investigate sonographically the effect of Gonogronema latifolium (***) on gastric emptying of semi-solid meals in healthy ***:In a randomized,placebo-controlled experiment,twenty-five clinically healthy dogs were randomly allotted into five groups of five dogs in each *** placebo group served as the control,and the low,moderate and high dose groups ingested the methanolic leaf extract of *** in capsules at 100 mg/kg,250 mg/kg and 500 mg/kg,respectively,while the prokinetic group ingested 0.5 mg/kg capsules of *** a 12-h fast,each group ingested its treatment capsules 30 min before the administration of a test *** of gastric emptying and blood glucoselevels were obtained 30 min before and immediately after the ingestion of the test meal and thereafter every 15 min for 4 *** was followed by further measurements every 30 min for another 2 ***:The gastric emptying times of the placebo,low dose,moderate dose,high dose and prokinetic dose groups were 127.0 ± 8.2 min,135.5 ± 3.7 min,155.5 ± 3.9 min,198.0 ± 5.3 min and 59.0 ± 2.5 min,*** emptying times of the moderate and high dose groups were significantly slower than in the placebo control group (155.5 ± 3.9 min,198.0 ± 5.3 min vs 127.0 ± 8.2 min,P=0.000).No significant difference in gastric emptying between the low dose and placebo control groups was noted (135.5 ± 3.7 min vs 127.0 ± 8.2 min,P=0.072).Gastric emptying of the prokinetic group was significantly faster than that of the control group (59.0 ± 2.5 min vs 127.0 ± 8.2 min,P=0.000).The hypoglycaemic effect of *** and gastric emptying were inversely related (r=-0.95,P=0.000).CONCLUSION:*** delays gastric emptying and lowers postprandial blood glucose in healthy *** reduces the postprandial blood glucose by delaying gastric emptying.

关键词： Gonogronema latifolium Gastric emptying Sonography Postprandial blood glucose Semi-solid meals

Growth of Four varieties of Coffea arabica L. Biofertilized with Rhizophagus intraradices and Azospirillum brasilense in Nursery

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American Journal of Plant sciences 2023年第5期14卷 552-568页

作者： Zoila C. Anzueto-Herón Juan F. Aguirre-Medina Juan F. Aguirre-Cadena Cadena-Iñiguez Pedro faculty of agronomic sciences—campus v Autonomous University of Chiapas Villaflores México faculty of Agricultural sciences—campus Iv Autonomous University of Chiapas Huehuetán México Instituto Nacional de Investigaciones Agrícolas y Pecuarias Campo Experimental Centro Chiapas Ocozocoautla México

Coffee production has decreased due to environmental and management factors. The current plantations are old and unproductive, also due to the rust problem, caused by the fungus Hemileia vastatrix Berk & Br. Furthermore, the shade in the production systems has decreased with the consequent increase in soil erosion, in addition to the increase in agrochemicals. Currently, the planting of new varieties with resistance to the fungus is increasing. Furthermore, it has been shown that various biofertilized perennial crops in nursery favor their growth. In this study, the effect of applying two beneficial microorganisms, Rhizophagus intraradices and/or Azospirillum brasilense, to the planting of four varieties of Coffea arabica L. was evaluated. The coffee varieties marseillase, geisha, sarchimor and costa rica 95 were established in bags with the following treatments: 1) control, 2) R. intraradices, 3) A. brasilense, 4) R. intraradices + A. brasilense. Morphological and physiological yield components were recorded 168 days after transplanting. Data was analyzed statistically and differences between treatments were compared according to Tukey (p ≤ 0.05). The results indicate that individual or combined biofertilization of microorganisms favors dry matter allocation compared to the control and the same is differentially assigned to the stem and root. The Specific Leaf Area (SLA) also showed differential response between applications of the microorganisms, in two varieties it increased when they were applied alone and in the others when they were applied together.

关键词： Rhizophagus intraradices Azospirillum brasilense Coffee varieties

Locally Enhanced Flow and Electric Fields Through a Tip Effect for Efficient Flow‑Electrode Capacitive Deionization

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Nano-Micro Letters 2025年第2期17卷 1-17页

作者： Ziquan Wang Xiangfeng Chen Yuan Zhang Jie Ma Zhiqun Lin Amor Abdelkader Maria‑Magdalena Titirici Libo Deng College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhen 518060People’s Republic of China Research Center for Environmental Functional Materials College of Environmental Science and EngineeringTongji University1239 Siping RoadShanghai 200092People’s Republic of China Department of Chemical and Biomolecular Engineering National University of SingaporeSingapore 117585Singapore Department of Engineering Faculty of Science and TechnologyBournemouth UniversityTalbot CampusFern BarrowPooleEngland BH125BBUK Institut de Chimie de Nice UniversitéCôte d’AzurUMR CNRS 727228 Av.Valrose06108 NiceFrance Department of Chemical Engineering Imperial College LondonSouth Kensington CampusExhibition RdLondon SW72AZUK

Low-electrode capacitive deionization(FCDI)is an emerging desalination technology with great potential for removal and/or recycling ions from a range of ***,it still suffers from inefficient charge transfer and ion transport kinetics due to weak turbulence and low electric intensity in flow electrodes,both restricted by the current ***,a new tip-array current collector(designated as T-CC)was developed to replace the conventional planar current collectors,which intensifies both the charge transfer and ion transport *** effects of tip arrays on flow and electric fields were studied by both computational simulations and electrochemical impedance spectroscopy,which revealed the reduction of ion transport barrier,charge transport barrier and internal *** the voltage increased from 1.0 to 1.5 and 2.0 v,the T-CC-based FCDI system(T-FCDI)exhibited average salt removal rates(ASRR)of 0.18,0.50,and 0.89μmol cm^(-2) min^(-1),respectively,which are 1.82,2.65,and 2.48 folds higher than that of the conventional serpentine current collectors,and 1.48,1.67,and 1.49 folds higher than that of the planar current ***,with the solid content in flow electrodes increased from 1 to 5 wt%,the ASRR for T-FCDI increased from 0.29 to 0.50μmol cm^(-2) min^(-1),which are 1.70 and 1.67 folds higher than that of the planar current ***,a salt removal efficiency of 99.89%was achieved with T-FCDI and the charge efficiency remained above 95%after 24 h of operation,thus showing its superior long-term stability.

关键词： Flow-electrode Capacitive deionization Current collector Tip effect Desalination

New Apsidal Motion in Four Eccentric Eclipsing Binaries:v610 Car,v944 Cep,v2815 Ori and v1260 Tau

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Research in Astronomy and Astrophysics 2022年第11期22卷 69-77页

作者： Ahmet Bulut Department of Physics Faculty of Arts and SciencesCanakkale Onsekiz Mart UniversityTerzioglu CampusTR-17020CanakkaleTurkiye Astrophysics Research Centre and Observatory Canakkale Onsekiz Mart UniversityTerzioglu CampusTR-17020CanakkaleTurkiye

This paper presents an apsidal motion *** apsidal motion analysis of the eccentric eclipsing binaries v610 Car(P=4.84 days),v944 Cep(P=6.56 days),v2815 Ori(P=2.13 days),and v1260 Tau(P=5.43 days)was performed using minima times from the O-C Gateway database,ASAS-3,ASAS-SN,and TESS,following Lacy’s *** rates of change of periastron longitude were found to be 0.0253±0.0041,0.0347±0.0015,0.0288±0.0010 and0.0294±0°.0079 cycle^(-1),*** the light curve study,the first photometric mass ratio of v944 Cep was found to be q=1.4994±0.0012.A new light curve of v944 Cep was obtained using TESS *** first absolute dimensions of v944 Cep were M_(1)=1.10±0.01 M_(⊙),M_(2)=1.64±0.02 M_(⊙),R_(1)=2.04±0.37 R_(⊙),R_(2)=3.77±0.67 R_(⊙)for the hotter primary component(T_(1)=4925 K),and M_(1)=1.04±0.01 M_(⊙),M_(2)=1.57±0.02 M_(⊙),R_(1)=2.26±0.36 R_(⊙),R_(2)=3.74±0.59 R_(⊙)for the cooler primary component(T_(1)=4475 K).For v610 Car,v944 Cep,v2815 Ori and v1260 Tau,the apsidal motion periods were found to be 188±26 yr,186±8 yr,73±3 yr and 182±38 yr,*** v944 Cep,the internal structural constants of the component stars log_(k2,obs)=-2.05±0.01 and log_(k2,theo)=-1.83 for hotter primary component and log_(k2,obs)=-1.97±0.01 and log_(k2,theo)=-1.89 for cooler primary component were calculated.

关键词： (stars:)binaries:eclipsing stars:fundamental parameters techniques:photometric

Tribological behavior of CrN-coated Cr–Mo–v steels used as die materials

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International Journal of Minerals,Metallurgy and Materials 2017年第12期24卷 1394-1402页

作者： Gulsah Aktas Celik Seyda Polat S.Hakan Atapek Kocaeli University Faculty of EngineeringDepartment of Metallurgical and Materials EngineeringUmuttepe Campus41380 KocaeliTurkey

DIN 1.2343 and 1.2367 steels are commonly used as die materials in aluminum extrusion, and single/duplex/multi-coatings enhance their surface properties. The design of an appropriate substrate/coating system is important for improving the tribological performance of these steels under service conditions because the load-carrying capacity of the system can be increased by decreasing the plastic deformation of the substrate. In this study, the tribological behavior of CrN-coated Cr–Mo–v steels(DIN 1.2343, 1.2367, and 1.2999 grades) was investigated using different setups and tribological pairs at room and elevated temperatures. The aim of this study was to reveal the wear resistance of a suggested system(1.2999/CrN) not yet studied and to understand both the wear and the failure characteristics of coated systems. The results showed that(i) among the steels studied, the DIN 1.2999 grade steel exhibited the lowest friction coefficient because it had the highest load-carrying capacity as a result of secondary hardening at elevated temperatures;(ii) at room temperature, both abrasive tracks and adhesive layers were observed on the worn surfaces; and(iii) a combination of chemical reactions and progressive oxidation caused aluminum adhesion on the worn surface, and the detachment of droplets and microcracking were the characteristic damage mechanisms at high temperatures.

关键词： Cr–Mo–v steels CrN coating aluminum extrusion tribological behavior