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TiO_(2)/WO_(3)heterogeneous structures prepared by electrospinning and sintering steps:Characterization and analysis of the impedance variation to humidity

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Journal of Advanced Ceramics 2019年第2期8卷 238-246页

作者： Evando S.ARAuJO victor n.S.LEAO Research Group on Electrospinning and nanotechnology Applications(GPEA-nano) Department of Materials ScienceUniversidade Federal do Vale do Sao Francisco

Relative humidity(RH) is a critical environmental variable for transportation and storage of products and for the quality guarantee of several other production processes and services. Heterogeneous structures prepared from the selective semiconductor oxides may improve the sensitivity to humidity due to the better electronic and surface properties, when compared to pristine oxides. This work shows an alternative fabrication route for producing titanium dioxide/tungsten trioxide(TiO2/WO3) heterogeneous structures(by electrospinning and sintering) for potential application on the RH detection. The microstructural properties of the materials were analyzed by scanning electron microscopy(SEM), energy dispersive X-ray analysis(EDS), X-ray diffraction, and Raman spectroscopy. The electrical characterization of the structures was performed by electrical impedance spectroscopy in RH range of 10%–100%. Results indicated a p-to n-type conduction transition at around 30%–40% RH for all tested settings. The analysis of the impedance signature to humidity showed that the amount of fiber layers on the electrode and working temperature are important parameters to improve the humidity sensing of the TiO2/WO3 systems.

关键词： electrospinning heterogeneous structures preparation relative humidity semiconductors

Resilience by design:How nature,nurture,environment,and microbiome mitigate stress and allostatic load

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World Journal of Psychiatry 2023年第5期13卷 144-159页

作者： Souhad Chbeir victor Carrión Department of Psychiatry and Behavioral Sciences School of MedicineStanford UniversityStanfordCA 94305United States

Resilience to psychological stress is defined as adaption to challenging life experiences and not the absence of adverse life *** of resilience include personality traits,genetic/epigenetic modifications of genes involved in the stress response,cognitive and behavioral flexibility,secure attachment with a caregiver,social and community support systems,nutrition and exercise,and alignment of circadian rhythm to the natural light/dark ***,resilience is a dynamic and flexible process that continually evolves by the intersection of different domains in human’s life;biological,social,and *** objective of this minireview is to summarize the existing knowledge about the multitude factors and molecular alterations that result from resilience to stress *** the multiple contributing factors in building resilience,we set out a goal to identify which factors were most supportive of a causal role by the current *** focused on resilience-related molecular alterations resulting from mind-body homeostasis in connection with psychosocial and environmental *** conclude that there is no one causal factor that differentiates a resilient person from a vulnerable ***,building resilience requires an intricate network of positive experiences and a healthy lifestyle that contribute to a balanced mind-body ***,a holistic approach must be adopted in future research on stress response to address the multiple elements that promote resilience and prevent illnesses and psychopathology related to stress allostatic load.

关键词： stress load alignment

Long-term changes in the plant ecology of an African savanna landscape and the implications for ecosystem theory and conservation management

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Ecological Processes 2021年第1期10卷 213-224页

作者： David Western victor n.Mose David Maitumo Caroline Mburu African Conservation Centre P.O.Box 15289-00509NairobiKeny

Background:Studies of the African savannas have used national parks to test ecological theories of natural ecosystems,including equilibrium,non-equilibrium,complex adaptive systems,and the role of top-down and bottom-up physical and biotic *** such studies have excluded the impact of pastoralists in shaping grassland ecosystems and,over the last half century,the growing human impact on the world’s *** mounting human impact calls for selecting indicators and integrated monitoring methods able to track ecosystem changes and the role of natural and human *** study draws on five decades of monitoring the Amboseli landscape in southern Kenya to document the declining role of natural agencies in shaping plant ecology with rising human ***:We show that plant diversity and productivity have declined,biomass turnover has increased in response to a downsizing of mean plant size,and that ecological resilience has declined with the rising probability of extreme shortfalls in pasture *** signature of rainfall and physical agencies in driving ecosystem properties has decreased sharply with growing human *** compare the Amboseli findings to the long-term studies of Kruger and Serengeti national parks to show that the human influence,whether by design or default,is increasingly shaping the ecology of savanna *** look at the findings in the larger perspective of human impact on African grasslands and the world rangelands,in general,and discuss the implications for ecosystem theory and conservation policy and ***:The Amboseli study shows the value of using long-term integrated ecological monitoring to track the spatial and temporal changes in the species composition,structure,and function of rangeland ecosystems and the role of natural and human agencies in the process of *** study echoes the widespread changes underway across African savannas and world’s rangelands,concluding that some level

关键词： Savannas Plants Human dominance Macroecology Conservation

Exploring kidney biopsy findings in congenital heart diseases:Insights beyond cyanotic nephropathy

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World Journal of nephrology 2024年第1期13卷 25-32页

作者： Jose Daniel Juarez-Villa Iván Zepeda-Quiroz Sebastián Toledo-Ramírez victor Hugo Gomez-Johnson Francisco Pérez-Allende Brian Ricardo Garibay-Vega Francisco E Rodríguez Castellanos Bernardo Moguel-González Edgar Garcia-Cruz Salvador Lopez-Gil Department of nephrology Instituto Nacional de Cardiología Ignacio ChavezMexico City 14080Mexico Congenital Heart Disease Instituto Nacional de Cardiología Ignacio ChavezMexico City 14080Mexico

BACKGROUnD The association between congenital heart disease and chronic kidney disease is well *** mechanisms of kidney damage associated with congenital heart disease have been *** etiology of kidneydisease has commonly been considered to be secondary to focal segmental glomerulosclerosis(FSGS),however,this has only been demonstrated in case reports and not in observational or clinical *** To identify baseline and clinical characteristics,as well as the findings in kidney biopsies of patients with congenital heart disease in our *** This is a retrospective observational study conducted at the nephrology Depart-ment of the national Institute of Cardiology“Ignacio Chávez”.All patients over 16 years old who underwent percutaneous kidney biopsy from January 2000 to January 2023 with congenital heart disease were included in the *** Ten patients with congenital heart disease and kidney biopsy were *** average age was 29.00 years±15.87 years with pre-biopsy proteinuria of 6193 mg/24 h±6165 mg/24 *** most common congenital heart disease was Fallot’s tetralogy with 2 cases(20%)and ventricular septal defect with 2(20%)*** the 10 cases,one case of IgA nephropathy and one case of membranoproliferative glomerulonephritis associated with immune complexes were found,receiving specific treatment after histopathological diagnosis,delaying the initiation of kidney replacement *** remaining 8 cases(80%),one case of FSGS with perihilar variety was found,while the other 7 cases were non-specific *** Determining the cause of chronic kidney disease can help in delaying the need for kidney replacement *** 2 out of 10 patients in our study,interventions were performed,and initiation of kidney replacement therapy was *** studies are needed to determine the usefulness of kidney biopsy in patients with congenital heart disease.

关键词： Renal biopsy Congenital heart disease Chronic kidney disease Focal segmental glomerulosclerosis

Sequential Analysis in the Identification of 3rd Order System Tract in the Abidjan Margin

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Phasor-domain Dynamic Model of Asymmetric Current Injection Controller for Converter-interfaced Generator

Open Journal of Applied Sciences（应用科学） 2024年第6期 1474页

作者： Blandine Akissi Egoran n’guessan Donald Ahoure Fori Yao Paul Assalé Sylvain Mondé Loukou victor n’da

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Journal of Modern Power Systems and Clean Energy 2021年第6期9卷 1269-1278页

作者： victor A.F.Almeida Glauco n.Taranto José M.T.Marinho Electrical Engineering Department of the Federal University of Rio de Janeiro(COPPE/UFRJ) Petrobras S.A.

This paper presents a controller model of asymmetric current injection for converter-interfaced generators suitable for root-mean-square(RMS)phasor-domain,fundamentalfrequency,three-phase,and dynamic simulation *** effectiveness of the proposed controller is assessed with simulations in test systems with high percentage of converter-interfaced *** simulations focus on the operation of protection relays that use negative-sequence quantities in their directional *** paper also presents and compares two strategies to limit reactive negative-sequence currents,and active and reactive positive-sequence currents.A tutorial test system and a regional system part of the actual Brazilian Interconnected Power System are used to assess the correctness of the proposed controller in three-phase fundamental-frequency RMS dynamic simulations.

关键词： Converter-interfaced generator three-phase model power system protection negative-sequence current injection negative-sequence current protection unbalanced fault three-phase root-mean-square(RMS)dynamic simulation

广义Piatetski-shapiro序列中的square-full数

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数学进展 2024年第2期53卷 303-309页

作者：祁瑾云郭振宇西北大学数论及其应用研究中心陕西西安710127 西安交通大学数学与统计学院陕西西安710049

广义Piatetski-shapiro序列是形如([αn^(c)+β])的序列,其中c>1且c■n.本文研究了广义Piatetski-shapiro序列中square-full数的分布.

关键词： square-full数 Piatetski-shapiro序列指数和

Efficiency and productivity analysis of vegetable farming within root and tuber-based systems in the humid tropics of Cameroon

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Journal of Integrative Agriculture 2017年第8期16卷 1865-1873页

作者： Ajapnwa Akamin Jean-Claude Bidogeza Jules Rene Minkoua n victor Afari-Sefa Faculty of Economics and Management University of Yaounde IIP.O.Box 18 Soa YaoundeCameroon Liaison Office Cameroon West and Central AfricaWorld Vegetable CenterP.O.Box 2008 Messa YaoundeCameroon Samanko Research Station West and Central AfricaWorld Vegetable CenterP.O.Box 320 BemakoMali

The study analyzes the technical efficiency of vegetable farmers in root and tuber-based farming systems within selected sites of the humid tropics of Cameroon. Multistage sampling was used to collect primary data from a cross-section of vegetable farmers drawn from eight selected sites in Santa sub division, northwest region of Cameroon. Stochastic frontier analysis was used to estimate the technical efficiency of vegetable farmer and to examine its determinants. The results showed that farmyard manure was the most productive factor input, followed by farm equipment and labor. The mean technical efficiency level was 67%, revealing production shortfalls and indicating possibilities of significantly increasing production with the current input Jevels. Female, as well as more educated farmers were found to be significantly more efficient than their counterparts. The results also showed that farmers become less technical efficient as farm sizes become larger. Our study findings suggest that smallholder farmers＇ access to manure, farm implements, and increased women participation in vegetable farming, will produce huge payoffs in vegetable production efficiency in Cameroon.

关键词： technical efficiency vegetable productivity farming systems intensification crop diversification stochasticfrontier analysis

Improved shape hardening function for bounding surface model for cohesive soils

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Journal of Rock Mechanics and Geotechnical Engineering 2014年第4期6卷 328-337页

作者： Andrés nieto-Leal victor n.Kaliakin Department of Civil & Environmental Engineering University of Delaware Newark DE 19716 USA Department of Civil Engineering Universidad Militar Nueva Granada Bogotá Colombia

A shape hardening function is developed that improves the predictive capabilities of the generalized bounding surface model for cohesive soils, especially when applied to overconsolidated specimens. This improvement is realized without any changes to the simple elliptical shape of the bounding surface, and actually reduces the number of parameters associated with the model by one.

关键词： Constitutive model Bounding surface plasticity shape hardening function Clay