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Chinese Physics Letters 2015年第12期32卷 35-39页

作者： Darwish Eed m. Physics Department Faculty of ScienceTaibah University Physics Department Faculty of ScienceSohag University

An explicit evaluation of the deuteron spin asymmetry and the associated Gerasimov-Drell Hearn （GDH） integral for coherent and incoherent π-photoproduction channels with inclusion of rescattering effects is presented. The helicity-dependent total inclusive photoabsorption cross section on the deuteron and the helicity-dependent semiexclusive channels γd→π± NN and γd→π0X （X = pn or d） are explicitly evaluated up to 1.5 GeV. Our model calculations indicate that convergence of the GDH integral is reached for π-production, while it is not completely reached for π-production. For the sum of 7d → πNN and γd→ π0d contributions to the finite GDH integral by explicit integration up to 1.5 GeV, a value of 249.73μb is obtained. The extracted results are compared with available experimental data from mAmI and ELSA. We find that our predictions fairly well reproduce the data in the μ±NN case, while fail to predict the measured shape of the μ0X channel.

关键词： GDH Contribution of Coherent and Incoherent

Response of Jatropha on a Clay Soil to Different Concentrations of micronutrients

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American Journal of Plant Sciences 2012年第10期3卷 1376-1381页

作者： A. A. Abd El-kader m. m. Hussein A. k. Alva Soils and Water Use Department National Research Center Cairo Egypt United States Department of Agriculture—Agricultural Research Service Vegetable and Forage Research Prosser USA Water Relations and Field Irrigation Department National Research Center Cairo Egypt

In recent years Jatropha curcas L. has emerged as a biofuel crop with potential for its production in marginal land with application of treated sewage water. Since this is a new crop for its profitable cultivation, additional research is needed to develop optimal management programs, including macro and micronutrients applications. A pot experiment was conducted in a Greenhouse at the National Research Center, Dokki, Cairo, Egypt, during 2010 summer to evaluate effects of varying concentrations of iron (Fe), manganese (mn), and zinc (Zn) in irrigation water (0, 50, 100, 150, 200 and 250 ppm) on the growth, biomass production, photosynthetic pigments, and mineral nutrients status in the plants. Increasing concentrations of Fe, mn, and Zn in irrigation water up to 150 ppm increased the biomass weight, photosynthetic pigments, and nutrient uptake by Jatropha plants. Further increase in concentrations of micronutrients showed negative effects on the above response parameters. Therefore, this study demonstrates that Jatropha can be grown under irrigation using waste water containing reasonable concentrations of micronutrients and heavy metals. This property of Jatropha provides some support for potential use of this crop for phytoremediation of metal contaminated soils. However, long term field research is needed to further verify both the above beneficial effects.

关键词： Irrigation Growth Jatropha curcas L. mineral nutrition Photosynthetic Pigments Heavy metals Sewage Sludge

Deposition behavior and tribological properties of diamond-like carbon coatings on stainless steels via chemical vapor deposition

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International Journal of minerals,metallurgy and materials 2018年第11期25卷 1335-1343页

作者： Labani mustafi m.m.Rahman mohammad Nur E Alam Al Nasim mohammad Asaduzzaman Chowdhury m.H.monir School of materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China School of Engineering RMIT UniversityMelbourneVictoria 3001Australia Dhaka University of Engineering and Technology Gazipur 1707Bangladesh

A systematic investigation was carried out to observe the deposition rate of a diamond-like carbon(DLC) coating on two stainless steel substrates by chemical vapor deposition(CVD). The objective of this research is to study the deposition behavior of the DLC coating and its tribological properties in different combinations of methane(CH_4) and nitrogen, which were used as precursor gases. The results reveal that the deposition rate increases with increasing CH_4 content up to 50 vol%. The hardness of the DLC-deposited layer also increases while the friction coefficient decreases with increasing CH_4 gas content up to 50% in the precursor gas mixture.

关键词： diamond-like carbon chemical vapor deposition methane and nitrogen gas mixtures deposition rate hardness friction coefficient

Gradual Band Energy to Passivate the Window Layer in Solar Cells

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Smart Grid and Renewable Energy 2017年第1期8卷 46-51页

作者： A. Amine m. Bouabdellaoui k. Zaz Y. mir m. Zazoui Laboratory of Condensed matter and Renewable Energy Faculty of Sciences and Technology University of Hassan II Casa-blanca Casablanca Morocco

The passivation layers at the front of the cell are often referred as to the window layer because it must be transparent so as the solar cell has a high efficiency. In this work, numerical simulation has been proposed to study the effect of the AlGaAs gradual and normal windows on the cell sensitivity to the electron irradiation so as to passivate the solar cell. To expect the effect of gradual window layers, the J-V and P-V characteristics are confirmed better energy conversion performance of the illuminated solar cells after irradiation. The short circuit current Jsc and the open circuit voltage Voc are evaluated for different electron irradiation fluencies. The results show how the gradual window layer improves resistance to electron irradiation through its own parameters.

关键词： Gradual Window Electric Field Degradation Solar Cell

A hierarchical path-segmentation movement ecology framework

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Ecological Processes 2022年第1期11卷 787-801页

作者： Wayne m.Getz Department of Environmental Sciences University of CaliforniaBerkeley 94708CAUSA School of mathematical Sciences University of KwaZulu-NatalDurbanSouth Africa

This paper lays out a hierarchical,appropriate-complexity framework for conceptualizing movement-path segments at different spatiotemporal scales in a way that facilitates comparative analyses and bridges behavior and mathematical *** then outlines a process for generating a multimode,multiscale stochastic simulation model that can be used to test animal movement hypotheses and make predictions of movement responses to management and global *** methods for analyzing movement data begin by generating step-length(SL)and turning-angle(TA)distributions from relocation time-series data,some of which are linked to ecological,landscape,and environmental *** frequency at which these data are collected may vary from sub-seconds to several *** kinds of questions that may be asked of these data,however,are very much scale *** hierarchical path-segmentation(HPS)framework presented here clarifies how the scale at which SL and TA data are collected relates to other sub-and super-diel *** arise because the information contained in SL and TA time series are often not directly relatable to the physiological,ecological,and sociological factors that drive the structure of movement paths at longer *** difficulties are overcome by anchoring the classification of movement types around the concept of fixed-period(24 h)diel activity routines and providing a bridge between behavioral/ecological and stochastic-walk concepts(means,variances,correlations,individual-state and local environmental covariates).This bridge is achieved through the generation of relatively short segments conceived as characteristic sequences of fundamental movement *** short segments are then used to characterize longer canonical-activity-mode segments that emerge through movement at behaviorally relevant sub-diel *** thus provides a novel system for integrating sub-minute movement sequences into canonical activity modes(CAms)that,i

关键词： Hierarchical path segmentation(HPS) Fundamental movement elements(FumEs) Canonical activity modes(CAms) Diel activity routines(DARs) Life-history movement phases(LimPS) multi-CAm metaFumE markov(m-cubed)models Biased correlated random walk models

尾涡/固体边界交互作用下表面压力的数值模拟(英文)

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船舶力学 2007年第6期11卷 813-819页

作者：何谟钦 m.伊斯兰姆 B.维奇 N.伯斯 B.科伯尔尼刘鹏飞加拿大大洋技术咨询公司加拿大纽芬兰纪念大学海洋工程系澳大利亚海运及流体力学研究中心澳大利亚海事学院加拿大科学院海洋技术研究所

当强劲的尾涡撞击到结构时, 其表面压力将呈现大幅的变化。这种大幅变化的脉动压力是引起结构震动以及水动力噪声的主要原因之一。许多相关的工程领域都希望使用相对经济的方法对此压力脉动进行有效地预报。本文介绍一种已经嵌入一面元... 详细信息

当强劲的尾涡撞击到结构时, 其表面压力将呈现大幅的变化。这种大幅变化的脉动压力是引起结构震动以及水动力噪声的主要原因之一。许多相关的工程领域都希望使用相对经济的方法对此压力脉动进行有效地预报。本文介绍一种已经嵌入一面元法程序(PROPELLA) 的尾涡砰击模型, 及其在一吊舱桨尾涡撞击支柱诱导表面压力模拟中的应用。由模拟的时均表面压力分布和相均压力的时序变化与对应的实验数据的比较来看, 数值模拟与试验结果吻合较好。

关键词：表面压力涡/固边界交互作用尾涡砰击面元法数值模拟

Buckling of 2D-FG Cylindrical Shells under Combined External Pressure and Axial Compression

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Advances in Applied mathematics and mechanics 2013年第3期5卷 391-406页

作者： R.mohammadzadeh m.m.Najafizadeh m.Nejati Department of mechanical Engineering Islamic Azad UniversityArak BranchArakIran Young Researchers Club Islamic Azad UniversityArak BranchArakIran

This paper presents the stability of two-dimensional functionally graded(2D-FG)cylindrical shells subjected to combined external pressure and axial compression loads,based on classical shell *** material properties of functionally graded cylindrical shell are graded in two directional(radial and axial)and determined by the rule of *** Euler’s equation is employed to derive the stability equations,which are solved by GDQ method to obtain the critical mechanical buckling loads of the 2D-FG cylindrical *** effects of shell geometry,the mechanical properties distribution in radial and axial direction on the critical buckling load are studied and compared with a cylindrical shell made of *** numerical results reveal that the 2D-FGm has a significant effect on the critical buckling load.

关键词： mechanical buckling 2D-FG cylindrical shell combined load classical shell theory GDQ method

model combining pre-transplant tumor biomarkers and tumor size shows more utility in predicting hepatocellular carcinoma recurrence and survival than the BALAD models

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World Journal of Gastroenterology 2018年第12期24卷 1321-1331页

作者： Nicha Wongjarupong Gabriela m Negron-Ocasio Roongruedee Chaiteerakij Benyam D Addissie Essa A mohamed kristin C mara William S Harmsen J Paul Theobald Brian E Peters Joseph G Balsanek melissa m Ward Nasra H Giama Sudhakar k Venkatesh Denise m Harnois michael R Charlton Hiroyuki Yamada Alicia Algeciras-Schimnich melissa R Snyder Terry m Therneau Lewis R Roberts Division of Gastroenterology and Hepatology Mayo ClinicRochesterMN 55905United States University of Puerto Rico medical Sciences Campus San Juan 00921Puerto Rico Department of medicine Faculty of MedicineChulalongkorn University and King Chulalongkorn Memorial HospitalThai Red Cross SocietyBangkok 10400Thailand Division of Biomedical Statistics and Informatics Mayo ClinicRochesterMN 55905United States Division of Laboratory medicine Department of Laboratory Medicine and PathologyMayo Clinic College of MedicineRochesterMN 55905United States Department of Radiology Mayo Clinic College of MedicineRochesterMN 55905United States Department of Transplantation Mayo Clinic FloridaJacksonvilleFL 32224United States Wako Life Sciences IncorporatedMountain ViewCA 94043United States

AIm To assess the performance of BALAD, BALAD-2 and their component biomarkers in predicting outcome of hepatocellular carcinoma(HCC) patients after liver *** BALAD score and BALAD-2 class are derived from bilirubin, albumin, alpha-fetoprotein(AFP), Lens culinaris agglutinin-reactive AFP(AFP-L3), and des-gammacarboxyprothrombin(DCP). Pre-transplant AFP, AFP-L3 and DCP were measured in 113 patients transplanted for HCC from 2000 to 2008. Hazard ratios(HR) for recurrence and death were calculated. Univariate and multivariate regression analyses were conducted. C-statistics were used to compare biomarker-based to predictive models. RESULTS During a median follow-up of 12.2 years, 38 patients recurred and 87 died. The HRs for recurrence in patients with elevated AFP, AFP-L3, and DCP defined by BALAD cut-off values were 2.42(1.18-5.00), 1.86(0.98-3.52), and 2.83(1.42-5.61), respectively. For BALAD, the HRs for recurrence and death per unit increased score were 1.48(1.15-1.91) and 1.59(1.28-1.97). For BALAD-2, the HRs for recurrence and death per unit increased class were 1.45(1.06-1.98) and 1.38(1.09-1.76). For recurrence prediction, the combination of three biomarkers had the highest c-statistic of 0.66 vs. 0.64, 0.61, 0.53, and 0.53 for BALAD, BALAD-2, milan, and UCSF, respectively. Similarly, for death prediction, the combination of three biomarkers had the highest c-statistic of 0.66 vs 0.65,0.61, 0.52, and 0.50 for BALAD, BALAD-2, milan, and UCSF. A new model combining biomarkers with tumor size at the time of transplant(S-LAD) demonstrated the highest predictive capability with c-statistics of 0.71 and 0.69 for recurrence and death. CONCLUSION BALAD and BALAD-2 are valid in transplant HCC patients, but less predictive than the three biomarkers in combination or the three biomarkers in combination with maximal tumor diameter(S-LAD).

关键词： alpha-fetoprotein AFP-L3 des-gammacarboxyprothrombin BALAD BALAD-2 Hepatocellular carcinoma Liver transplant Recurrence Outcome

ABC efflux transporters at blood-central nervous system barriers and their implications for treating spinal cord disorders

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Neural Regeneration Research 2020年第7期15卷 1235-1242页

作者： Liam m. koehn Department of Pharmacology and Therapeutics the University of Melbourne

The barriers present in the interfaces between the blood and the central nervous system form a major hurdle for the pharmacological treatment of central nervous system injuries and *** family of ATP-binding cassette(ABC)transporters has been widely studied regarding efflux of medications at blood-central nervous system *** efflux transporters include P-glycoprotein(abcb1),‘breast cancer resistance protein'(abcg2)and the various‘multidrug resistance-associated proteins'(abccs).Understanding which efflux transporters are present at the blood-spinal cord,blood-cerebrospinal fluid and cerebrospinal fluid-spinal cord barriers is necessary to determine their involvement in limiting drug transfer from blood to the spinal cord *** developments in the blood-brain barrier field have shown that barrier systems are dynamic and the profile of barrier defenses can alter due to conditions such as age,disease and environmental *** means that a true understanding of ABC efflux transporter expression and localization should not be one static value but instead a range that represents the complex patient subpopulations that *** the present review,the blood-central nervous system barrier literature is discussed with a focus on the impact of ABC efflux transporters on:(i)protecting the spinal cord from adverse effects of systemically directed drugs,and(ii)limiting centrally directed drugs from accessing their active sites within the spinal cord.

关键词： ABC transporters ATP-binding cassette BCRP blood-brain barrier blood-spinal cord barrier efflux mRP P-glycoprotein PGP spinal cord injury

*** Part Ⅱ:Exploring Humid Heat Extremes Using Wet Bulb Temperature Indices

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Advances in Atmospheric Sciences 2023年第11期40卷 1968-1985页

作者： kate m.WILLETT met Office Hadley Centre FitzRoy RoadExeterEX13PBU.K.

Heat events may be humid or *** several indices incorporate humidity,such combined indices obscure identification and exploration of heat events by their different humidity *** new *** global gridded monitoring product uniquely provides a range of wet and dry bulb temperature extremes *** of this new data product demonstrates its value as a tool for quantifying exposure to humid verses dry heat *** also enables exploration into“stealth heat events”,where humidity is high,perhaps enough to affect productivity and health,while temperature remains *** events may not typically be identified as“heat events”by temperature-focused heat *** 1973-2022,the peak magnitude of humid extremes(maximum daily wet bulb temperature over a month;T_(w)X)for the global annual mean increased significantly at 0.13±0.04℃(10 yr)^(−1),which is slightly slower than the global annual mean T_(w) increase of 0.22±0.04℃(10 yr)^(−1).The frequency of moderate humid extreme events per year(90th per-centile daily maxima wet bulb temperature exceedance;T_(w)X90p)also increased significantly at 4.61±1.07 d yr^(−1)(10 yr)^(−1).These rates were slower than for temperature extremes,TX and TX90p,which respectively increased significantly at 0.27±0.04℃(10 yr)^(−1) and 5.53±0.72 d yr^(−1)(10 yr)^(−1).Similarly,for the Uk/Europe focus region,JJA-mean T_(w)X increased significantly,again at a slower rate than for TX and mean T_(w).*** shows some evidence of“stealth heat events”occurring where humidity is high but temperature remains more moderate.

关键词： wet bulb temperature heat extremes climate monitoring