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Journal of Data Analysis and Information Processing 2024年第2期12卷 151-162页

作者： Christopher Watitwa Makokha Ananda Kube oscar Ngesa Department of Mathematics Pan African University Institute of Basic Sciences Technology and Innovation Nairobi Kenya Department of Mathematics and Actuarial Sciences Kenyatta University Nairobi Kenya Department of Mathematics Statistics and Physical Sciences Taita Taveta University Voi Kenya

Peer-to-peer (P2P) lending offers an alternative way to access credit. Unlike established lending institutions with proven credit risk management practices, P2P platforms rely on numerous independent variables to evaluate loan applicants’ creditworthiness. This study aims to estimate default probabilities using a mixture-of-experts neural network in P2P lending. The approach involves coupling unsupervised clustering to capture essential data properties with a classification algorithm based on the mixture-of-experts structure. This classic design enhances model capacity without significant computational overhead. The model was tested using P2P data from Lending Club, comparing it to other methods like Logistic Regression, AdaBoost, Gradient Boosting, Decision Tree, Support Vector Machine, and Random Forest. The hybrid model demonstrated superior performance, with a Mean Squared Error reduction of at least 25%.

关键词： Credit-Scoring Clustering Classification Neural Networks

Drought Tolerance and Recovery of the Sedge Carex planostachys (Cyperaceae) from Central Texas Woodlands

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American Journal of Plant Sciences 2024年第9期15卷 746-765页

作者： E. Rob Wayne oscar William Van Auken Natural Sciences Department St. Philips College San Antonio USA Department of Integrative Biology The University of Texas at San Antonio San Antonio USA

Carex planostachys Kunze (Cyperaceae, Cedar sedge) is an herbaceous species in a genus commonly inhabiting mesic or hydric habitats. Carex planostachys is found in arid and semi-arid Juniperus woodlands. Arid conditions impose survival challenges to plants in dry areas. Some plants have plasticity responses to soil water content and continued normal though reduced functions through droughts, but most herbaceous plants do not survive. Limited previous studies have suggested C. planostachys is tolerant of drought. Physiological responses of C. planostachys from Juniperus woodlands was examined is this study to determine how long plants could survive without water and if they are capable of recovery from very negative water potentials beyond what is considered the permanent wilting point for most herbaceous plants. Plants were placed in pots in partial shade in this experiment. Water loss from the soil with plants was an inverse 2nd order polynomial function with soil water decreasing from 32% to 8% by day 28 of the study. Leaf water potential was also an inverse 2nd order polynomial function but did not decline significantly until 14 days without watering. Leaf water potential was −10.0 MPa after 35 days without watering. Non-watered plants Anet, (photosynthetic rate) was significantly lower compared to the water treatment by day 21 as was stomatal conductance and transpiration. When non-watered plants were watered after 21, 28 or 35 days, full recovery of physiological responses occurred within 7 days. The length of time that C. planostachys was able to withstand drought was greater than the annual trends in lack of precipitation during springtime in this area. Carex planostachys can photosynthesize at water stress between −8 and −10 MPa. Carex planostachys drought and shade tolerance enables it to occupy an understory niche devoid of other herbaceous plants.

关键词： CO2 Uptake Conductance Gas Exchange Photosynthesis Respiration Transpiration Water Stress Water Potential.

Gas Exchange Rates of Texas Persimmon (Diospyros texana) in Central Texas Woodlands

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American Journal of Plant Sciences 2024年第5期15卷 329-348页

作者： Matthew B. Grunstra oscar W. Van Auken Department of Integrative Biology University of Texas at San Antonio San Antonio TX USA

Diospyros texana (Texas persimmon) is a secondary species in most Juniperus ashei/Quercus fusiformis woodlands in central Texas. It has high density, but plants are mostly in the community understory. Light response curves at ambient and elevated levels of CO2 and temperature were measured for D. texana. The Anet (photosynthetic rate) increased significantly as both light level and CO2 levels increased but not temperature. The Amax (maximum photosynthetic rate) of D. texana in full sun at elevated levels of CO2 was increased for all treatments. Stomatal conductance increased with levels of CO2 but only if the interaction was removed from the model. Intercellular levels of CO2 increased with both temperature and CO2 treatments as did water use efficiency (WUE). Furthermore, light saturation (Lsat) increased with CO2 treatments and light compensation (Lcp) increased with temperature. The dark respiration (Rd) increased with both temperature and CO2 treatments. Markov population models suggested D. texana populations would remain ecologically similar in the future. However, sub-canopy light levels and herbivory should be considered when examining population projections. For example, Juniperus ashei juveniles are not recruited into any canopy unless there are high light levels. Herbivory reduces the success of Quercus juveniles from reaching the canopy. These factors do not seem to be a problem for D. texana juveniles which would allow them to reach the canopy without need of a high light gap and are not prevented by herbivory. Thus, Juniperus/Quercus woodlands will change in the future to woodlands with D. texana a more common species.

关键词： Replacement Dynamics Ecological Succession CO2 Concentrations Temperature Levels Photosynthetic Rates Drought Tolerance Herbivory Species Replacement Encroachment Juniper

Bile-acid-induced cell injury and protection

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World Journal of Gastroenterology 2009年第14期15卷 1677-1689页

作者： Maria J perez oscar Briz Research Unit University Hospital of Salamanca Laboratory of Experimental Hepatology and Drug Targeting CIBERehd University of Salamanca E.D. 129 37007 Salamanca Spain

Several studies have characterized the cellular and molecular mechanisms of hepatocyte injury caused by the retention of hydrophobic bile acids （BAs） in cholestatic diseases. BAs may disrupt cell membranes through their detergent action on lipid components and can promote the generation of reactive oxygen species that, in turn, oxidatively modify lipids, proteins, and nucleic acids, and eventually cause hepatocyte necrosis and apoptosis. Several pathways are involved in triggering hepatocyte apoptosis. Toxic BAs can activate hepatocyte death receptors directly and induce oxidative damage, thereby causing mitochondrial dysfunction, and induce endoplasmic reticulum stress. When these compounds are taken up and accumulate inside biliary cells, they can also cause apoptosis. Regarding extrahepatic tissues, the accumulation of BAs in the systemic circulation may contribute to endothelial injury in the kidney and lungs. In gastrointestinal cells, BAs may behave as cancer promoters through an indirect mechanism involving oxidative stress and DNA damage, as well as acting as selection agents for apoptosis-resistant cells. The accumulation of BAs may have also deleterious effects on placental and fetal cells. However, other BAs, such as ursodeoxycholic acid, have been shown to modulate BA-induced injury in hepatocytes. The major beneficial effects of treatment with ursodeoxycholic acid are protection against cytotoxicity due to more toxic BAs; the stimulation of hepatobiliary secretion; antioxidant activity, due in part to an enhancement in glutathione levels; and the inhibition of liver cell apoptosis. Other natural BAs or their derivatives, such as cholyI-N- methylglycine or pharmacological properties. cholylsarcosine, interest owing have also aroused to their protective

关键词： Apoptosis Cholestasis Liver Necrosis Oxidative stress Ursodeoxycholic acid

Hematological abnormalities in liver cirrhosis

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World Journal of Hepatology 2024年第9期16卷 1229-1244页

作者： oscar Manuel Fierro-Angulo JoséAlberto González-Regueiro Ariana Pereira-García Astrid Ruiz-Margáin Fernando Solis-Huerta Ricardo Ulises Macías-Rodríguez Department of Gastroenterology Instituto Nacional de Ciencias Médicas y Nutrición Salvador ZubiránMexico 14080Mexico Department of Hematology Instituto Nacional de Ciencias Médicas y Nutrición Salvador ZubiránMexico 14080Mexico

Hematological abnormalities are common in cirrhosis and are associated with various pathophysiological *** have documented a prevalence of thrombocytopenia,leukopenia,and anemia in patients with compensated cirrhosis of 77.9%,23.5%,and 21.1%,*** abnormalities carry significant clinical implications,including considerations for invasive procedures,infection risk,bleeding risk,and ***,cirrhosis was believed to predispose patients to bleeding due to alterations observed in classical coagula-tion tests such as prothrombin time,partial thromboplastin time,international normalized ratio,and ***,this understanding has evol-ved,and cirrhosis patients are now also acknowledged as being at a high risk for thrombotic *** in cirrhosis patients presents a complex pheno-type,with procoagulant and anticoagulant abnormalities offsetting each *** multifactorial phenomenon is inadequately reflected by routine laboratory *** complications are more prevalent in decompensated cirrhosis and may correlate with disease *** is primarily associated with portal hypertension,endothelial dysfunction,mechanical vessel injury,dissem-inated intravascular coagulation,endotoxemia,and renal *** review comprehensively outlines hematologic index abnormalities,mechanisms of hemostasis,coagulation,and fibrinolysis abnormalities,limitations of laboratory testing,and clinical manifestations of bleeding and thrombosis in patients with liver cirrhosis.

关键词： Cirrhosis Anemia Leukopenia Thrombocytopenia Coagulopathy Bleeding Thrombosis

Navigating Market Choices: Understanding Carrot Market Outlet Selection among Smallholder Farmers in Kenya

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Agricultural Sciences 2024年第6期15卷 676-703页

作者： Hillary Kiprotich Ngeno Ngenoh Evans oscar Ayuya Ingasia Hillary K. Bett State Department for Crop Development and Agricultural Research Ministry of Agriculture Livestock Fisheries and Cooperatives Nairobi Kenya Department of Agricultural Economics and Agribusiness Management Egerton University Egerton Kenya Brooklyn Economic Consulting Limited Nairobi Kenya

This research delves into the hurdles and strategies aimed at augmenting the market involvement of smallholder carrot farmers in Nakuru County, Kenya. Employing a Multinomial Logit (MNL) model, it scrutinizes the factors influencing the selection of marketing outlets among carrot farmers. The findings unveil that a significant majority (81%) of surveyed farmers actively participate in diverse market outlets, encompassing the farm gate, cleaning point, local market, external market, and export market. Notably, pivotal buyers include aggregators, brokers, wholesalers, retailers, and consumers, with transactions predominantly occurring at the farm level. Additionally, the analysis discerns substantial influences of socio-economic characteristics, experiential factors, and geographical proximity on farmers’ choices of market outlets. Specifically, gender, age, land size, farming experience, and distance to markets emerge as critical determinants. Moreover, the study delves into the examination of market margins along the carrot value chain, shedding light on the potential profitability of carrot farming in the region. Remarkably, higher average gross margins are identified in export and external markets, signaling lucrative prospects for farmers targeting these segments. However, disparities in profit distribution between farmers and traders underscore the necessity for interventions to ensure equitable value distribution throughout the value chain. These findings underscore the imperative for tailored interventions to tackle challenges and foster inclusive agricultural development. Strategies such as farmer organizations, contracting, and vertical integration are advocated to enhance market access and profitability for smallholder carrot farmers. Thus, this study enriches our comprehension of the dynamics within carrot value chains and provides valuable insights for policymakers and development practitioners aiming to uplift rural livelihoods and bolster food security.

关键词： Market Outlet Selection Smallholder Farmers Multinomial Logit Model Determinants Carrot Value Chain

Superplasticity of a friction stir processed overaged WE54 magnesium alloy

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Journal of Magnesium and Alloys 2022年第11期10卷 3156-3166页

作者： oscar A.Ruano Marta Alvarez-leal Alberto Orozco-Caballero Fernando Carreño Physical Metallurgy Department CENIM-CSICAv.Gregorio del Amo 828040 MadridSpain Department of R&D and programmes Technology Centre of Metal-Mechanical and Transport(CETEMET).Avda.1°de Mayos/n.LinaresJaén2370Spain Department of Mechanical Engineering Chemistry and Industrial DesignPolytechnic University of MadridRonda de Valencia 328012MadridSpain

The coarse-grained WE54 magnesium alloy was heat treated in order to have minimum hardness minimizing the effects of precipitates and solid solution. Friction stir processing(FSP) was applied in severe conditions to obtain fine, equiaxed and highly misoriented grains, with grain sizes even less than 1 μm. The high severity of processing demonstrated to have a strong impact in the microstructure. Consequently,the processed materials exhibited excellent superplasticity at the high strain rate 10^(-2)s^(-1), and temperatures between 300 and 400 ℃. The maximum tensile superplastic elongation of 756% was achieved at 400 ℃ thanks to the operation of grain boundary sliding mechanism(GBS). Besides the new data obtained through tensile testing, the paper deals with a transcendental question regarding the large differences in strain rate values at a given stress in the superplastic regime at maximum elongation compared to other magnesium-based alloys. With this is mind, 19 magnesium alloys from 22 different investigations were analyzed to give some light to this behavior that never was treated before. It is proposed that this behavior has to be attributed to the accommodation process, necessary for GBS to occur, which is hindered by reinforcing solutes.

关键词： WE54 magnesium alloy Friction stir processing Processing severity Superplasticity Grain boundary sliding Solutes

An in-depth understanding of the role and mechanisms of T cells in immune organ aging and age-related diseases

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Science China Life Sciences 2024年

作者： Yudai Xu Zijian Wang Shumin Li Jun Su Lijuan Gao Junwen Ou Zhanyi Lin oscar Junhong Luo Chanchan Xiao Guobing Chen Department of Microbiology and Immunology School of Medicine Institute of Geriatric Immunology School of Medicine Jinan University Key Laboratory of Viral Pathogenesis & Infection Prevention and Control (Jinan University) Ministry of Education Guangdong-Hong Kong-Macau Great Bay Area Geroscience Joint Laboratory School of Medicine Jinan University First Affiliated Hospital Jinan University Anti Aging Medical Center Clifford Hospital Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences) Southern Medical University Department of Systems Biomedical Sciences School of Medicine Jinan University The Sixth Affiliated Hospital of Jinan University (Dongguan Eastern Central Hospital) Jinan University Zhuhai Institute of Jinan University Jinan University

T cells play a critical and irreplaceable role in maintaining overall health. However, their functions undergo alterations as individuals age. It is of utmost importance to comprehend the specific characteristics of T-cell aging, as this knowledge is crucial for gaining deeper insights into the pathogenesis of aging-related diseases and developing effective therapeutic strategies. In this review, we have thoroughly examined the existing studies on the characteristics of immune organ aging. Furthermore, we elucidated the changes and potential mechanisms that occur in T cells during the aging process. Additionally, we have discussed the latest research advancements pertaining to T-cell agingrelated diseases. These findings provide a fresh perspective for the study of T cells in the context of aging.

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Characterization of Aquifers in Crystalline and Crystallophyll Basement Zones Using the Electrical Resistivity Method (Trails and Electrical Soundings) in the Gagnoa Region, (Central-Western Côte d’Ivoire)

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International Journal of Geosciences 2024年第6期15卷 511-523页

作者： oscar Zahibo Onétié Assoué Kouakou Sylvestre Kouadio Kotchi Rodrigue Orou Maxime Assa Abe Department of Geosciences Peleforo Gon Coulibaly University Korhogo Cte dIvoire Department of Agriculture and New Technologies University of San Pedro San Pedro Cte dIvoire

Introduction: Located in the central-western part of Côte d’Ivoire, the subsoil of the Gagnoa region is made up of sedimentary volcano formations and granitoids with developed fracturing. This complex Precambrian basement contains most of the region’s water resources. This is at the origin of the high failure rate during the various hydrogeological prospecting campaigns. Methodology: The database consists of resistivities from 42 holes and 51 trails drilled as part of the implementation of high-throughput drilling in the study area. The objective of this study is to deepen the knowledge of the fissured basement by interpreting profile curves and electrical soundings. It will be a question of classifying the different types of anomalies obtained on the profiles and their shapes. The orientation of the lineaments observed on the profiles was determined. Results: The interpretation of the geophysical data revealed various anomalies, the main ones being of the CC (Conductor Compartment) and CEDP (Contact between two bearings) types. These types of anomalies are mainly expressed in various forms: the “V”, “W” and “U” shapes. From these anomalies and the appearance of the electrical profiles, lineaments and their orientations were identified with N90-100, N130-140, N170-180 as major orientations. Conclusion: These results could contribute to a better understanding of the fractured environment of the Gagnoa region.

关键词： Basement Electrical Profiles Sounding Curves Resistivities

A comprehensive look at the psychoneuroimmunoendocrinology of spinal cord injury and its progression: mechanisms and clinical opportunities

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Military Medical Research 2024年第2期11卷 228-267页

作者： Miguel A.Ortega oscar Fraile-Martinez Cielo García-Montero Sergio Haro Miguel Ángel Álvarez-Mon Diego De Leon-Oliva Ana M.Gomez-Lahoz Jorge Monserrat Mar Atienza-Pérez David Díaz Elisa Lopez-Dolado Melchor Álvarez-Mon Department of Medicine and Medical Specialities University of Alcala28801 Alcala de HenaresSpain Ramón y Cajal Institute of Sanitary Research(IRYCIS) 28034 MadridSpain Department of Psychiatry and Mental Health Hospital Universitario Infanta Leonor28031 MadridSpain Service of Rehabilitation National Hospital for Paraplegic PatientsCarr.de la PeraledaS/N45004 ToledoSpain Immune System Diseases‑Rheumatology Service and Internal Medicine University Hospital Príncipe de Asturias(CIBEREHD)28806 Alcala de HenaresSpain

Spinal cord injury(SCI)is a devastating and disabling medical condition generally caused by a traumatic event(primary injury).This initial trauma is accompanied by a set of biological mechanisms directed to ameliorate neural damage but also exacerbate initial damage(secondary injury).The alterations that occur in the spinal cord have not only local but also systemic consequences and virtually all organs and tissues of the body incur important changes after SCI,explaining the progression and detrimental consequences related to this ***(PNIE)is a growing area of research aiming to integrate and explore the interactions among the different systems that compose the human organism,considering the mind and the body as a *** initial traumatic event and the consequent neurological disruption trigger immune,endocrine,and multisystem dysfunction,which in turn affect the patient's psyche and *** the present review,we will explore the most important local and systemic consequences of SCI from a PNIE perspective,defining the changes occurring in each system and how all these mechanisms are ***,potential clinical approaches derived from this knowledge will also be collectively presented with the aim to develop integrative therapies to maximize the clinical management of these patients.

关键词： Spinal cord injury(SCI) Psychoneuroimmunoendocrinology(PNIE) Secondary injury Immunoinflammatory dysfunction Gut microbiota Translational opportunities