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Atypical Variations of Water Conductivity Prior to Tectonic Earthquakes

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International Journal of Geosciences 2015年第12期6卷 1367-1385页

作者： fidel Martínez-García Arturo Colín-Cruz Salvador Adame-Martínez Jorge J. Ramírez-García Center of Proposed Drafts of the South Pacific Federal Electricity Commission Cuernavaca Morelos Mexico State Mexico Faculty of Chemistry Autonomous University of Mexico State Toluca de Lerdo Mexico State Mexico Faculty of Urban and Regional Planning Autonomous University of Mexico State Toluca de Lerdo Mexico State Mexico

Within the framework of precursor events related to earthquakes, this paper analyzes the possible effect on the aquatic environment of the surrounding energy that accompanies earthquakes, particularly in the area where oceanic and continental plates collide (Cocos Plate and North American Plate, south of Mexico). As a preamble, the types of precursor events, characteristics, and their possible origin are described. A project was designed under the assumption that in areas with high frequency and intensity seismicity there is an electrical and electromagnetic potential promoter which is detectable and assessable indirectly by measuring water conductivity behavior, which also may have atypical variations of data;the outcome of intensive conductivity monitoring in different settings, natural as well as manmade (wellsprings, artesian well and a cistern), are presented herein. The results of the conductivity monitoring for seven months, highlight two patterns in data behavior: one pattern shows the subtle dependence of data behavior on the geographic location of data monitoring instruments, revealing that could have a slight relationship between areas with increased seismic frequency and intensity and the presence of atypical conductivity variations. Another pattern reveals the possible relationship between atypical variations in conductivity and subsequent earthquake events;a total of 241 seismic events were analyzed and 59 of them are provided as evidence related with patterns mentioned.

关键词： Earthquakes Precursor Events Natural Water Conductivity Subduction Plates Cocos Plate Electromagnetic Fields Earth’s Electromagnetic Pulses

Sex-dependent resilience to extreme drought events: implications for climate change adaptation of a South American endangered tree species

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Ecological Processes 2024年第2期13卷 48-60页

作者： Sergio Piraino Martín Ariel Hadad Yanina Antonia Ribas-Fernández fidel Alejandro Roig Laboratorio de Dendrocronología e Historia Ambiental (IANIGLA CONICET ) Facultad de Ciencias Agrarias Universidad Nacional de Cuyo Laboratorio de Dendrocronología de Zonas áridas (CIGEOBIO CONICET ) Gabinete de Geología Ambiental (INGEO UNSJ) Hémera Centro de Observación de la Tierra Facultad de Ciencias Universidad Mayor

Background Recent changes in climatic trends are resulting in an increased frequency and intensity of extreme events, with unknown effect on ecosystem dynamics in the near future. Extreme drought episodes are recognized as disturbance factors capable of modifying forest dynamics and tree growth. Within this context, dioecious tree species may be impacted by climatic extremes, affecting male/female proportions and, consequently, reproductive processes and species persistence. Therefore, there is an urgent need for species-specific assessments of growth tolerance to extreme dry spells in dioecious tree species, to establish effective conservation strategies for these particular natural resources. Araucaria araucana(araucaria), an endangered dioecious Patagonian tree species, has recently undergone decay and mortality episodes in response to increasing dry climatic conditions. While sex-dependent tolerance to extreme drought episodes has been assessed in the species' humid distribution range, there is still a lack of information on the gender-based resilience of trees growing in the drier environments of the species' *** We reconstructed, through dendrochronological methods, the sex-dependent response of 105 araucaria individuals(55 female and 50 male trees) to five regional extreme dry spells employing a set of different indices. Resistance, recovery period, and average growth reduction of standardized tree-ring growth were examined, analysing the effect of biotic(sex, pre-drought stem tree growth) and abiotic(local climatic conditions before, during, and after extreme climatic episodes) factors on tree *** Sex influences only the species resistance to climatic disturbance, with male individuals showing lower tolerance to extreme drought events. Pre-drought radial growth rates and local meteorological conditions preceding, during, and following extreme dry spells strongly modulated araucaria radial growth resilience regardless of tree s

关键词： Araucaria Climate change Dendrochronology Extreme drought event Resilience

Sub-assemblages distribution of Giardia duodenalis and its association with clinical symptoms in children from Sancti Spíritus,Cuba

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Journal of Coastal Life Medicine 2015年第11期 864-868页

作者： Luis Jerez Puebla fidel anúnez Alexey Brito García Lázara Rojas Rivero Irais Atencio Millán Raúl CordovíPrado Department of Parasitology Tropical Medicine Institute"Pedro Kourí"HavanaCuba Provincial Centre of Hygiene Epidemiology and Microbiology of Sancti SpíritusCuba

Objective:To determine the prevalence of sub-assemblages of Giardia duodenalis(***)causing infection in preschool children in a central region of ***:A cross-sectional study was conducted on 417 children from Sancti Spiritus from January to June 2013.A PCR amplification of the glutamate dehydrogenase(gdh)gene was performed for all positive samples in direct microscopic examination to enable sub-assemblages ***:The prevalence of *** in preschool children was 10.8%.DNA from 39 of 45(86.7%)samples was successfully amplified by PCR-restriction fragment length polymorphism analysis of the gdh *** fragment length polymorphism analysis classified the 39 gdh amplicons in sub-assemblages BIII(11,28.2%),AII(8,20.5%)and BIV(4,10.3%).Mixed infections accounted for 41%,with the pattern AII/BIII(12,30.7%)being the *** pain was statistically associated with infection with sub-assemblage ***:Sub-assemblage BIII was the most commonly identified in the population of children studied,and significantly associated with abdominal pain in the symptomatic *** defining tools to discriminate sub-assemblage and genotype levels to correlate with clinical data are needed in further *** studies in endemic settings are required to elucidate the role that assemblage types play in *** infections in vulnerable populations,such as children.

关键词： Giardia duodenalis Prevalence Children Sub-assemblages PCR-restriction fragment length polymorphism Cuba

Quality evaluation of Nothofagus pumilio seeds linked to forest management and climatic events

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Ecological Processes 2024年第1期13卷 98-107页

作者： Julian Rodríguez-Souilla Jimena E.Chaves María Vanessa Lencinas Juan Manuel Cellini fidel A.Roig Pablo L.Peri Guillermo Martinez Pastur Laboratorio de Recursos Agroforestales Centro Austral de Investigaciones Científicas (CADIC) Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET ) Laboratorio de Investigaciones en Maderas (LIMAD) Universidad Nacional de la Plata (UNLP) Instituto Argentino de Nivología Glaciología y Ciencias Ambientales (IAN-IGLA) Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET ) Instituto Nacional de Tecnología Agropecuaria (INTA) Universidad Nacional de la Patagonia Austral (UNPA) Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET )

Background Forest ecosystems undergo significant transformations due to harvesting and climate fluctuations, emphasizing the critical role of seeding in natural regeneration and long-term structural preservation. Climate change further amplifies these dynamics, affecting phenology across species and regions. In Tierra del Fuego(Argentina), Nothofagus pumilio(lenga) forests represent the most important timber resource, and it is managed through different silvicultural strategies. This species demonstrates notable post-disturbance regeneration, yet seed fall exhibits signifi-cant variability, leading to variations in seed quality(e.g., viability). This study aims to assess fluctuations in N. pumilio seed quality, determine how it varies concerning forest management strategies, annual productivity, and the co-occurrence of climatic phenomena including El Ni?o-Southern Oscillation(ENSO) and the Southern Annular Mode(SAM).Results Viable seeds represented 18.4% of the total, notably higher in unharvested than in managed areas. Con-versely, empty seeds were more prevalent in harvested areas(> 75%). Seed quality exhibited significant differences across silvicultural treatments, except for insect-predated seeds, which had similar proportions across all areas, though dispersed retention showed higher predation. When considering years with varying production levels, high-production years favoured full and viable seeds, particularly in unharvested forests and aggregated retention, while low-production years saw reduced viability across all treatments. Quadratic models revealed that viability increased with seed production, where unharvested forests achieved the highest values. Climate variability influenced seed proportions, where ENSO+/SAM+ promoting more full and viable seeds, while ENSO–/SAM+ favoured non-predated seeds, especially in unharvested *** Seed quality varies among treatments and years with different levels of seeding. Variations in seed qual-ity, l

关键词： Forest management Seeding Climate change Extreme event Patagonia

Extreme drought triggers parallel shifts in wood anatomical and physiological traits in upper treeline of the Mediterranean Andes

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Ecological Processes 2024年第1期13卷 132-143页

作者： Luiz Santini Jr. Dylan Craven Daigard Ricardo Ortega Rodriguez Manolo Trindade Quintilhan Stephanie Gibson-Carpintero Cristina Aravena Torres fidel A.Roig Ariel A.Mu?oz Alejandro Venegas-Gonzalez Hémera Centro de Observación de la Tierra Universidad Mayor GEMA Center for Genomics Ecology and Environment Universidad Mayor Data Observatory Foundation ANID Technology Center Depart-ment of Forest Sciences ESALQ-University of Sao Paulo Department of Plant Biology Institute of Biology University of Campinas Instituto de Geografía Universidad Nacional Autónoma de México (UNAM) Argentine Institute of Nivology Glaciology and Environmental Sciences(IANIGLA CONICET ) Institute of Geography Pontificia Universidad Católica de Valparaíso Instituto de Ciencias Agroalimentarias Animales y Ambientales (ICA3) Universidad de O'Higgins

Background Treeline ecotones of Mediterranean ecoregions have been affected by the increasing intensity and severity of droughts. Even though the effect of droughts on forest dynamics has been widely documented, knowledge is relatively scarce of how extreme climate episodes affect the hydraulic structure and, therefore, the phys-iology of woody plants. The Mediterranean Andes have experienced an uninterrupted period of drought since 2010, including an extremely dry year in 2019 with approximately 80% rainfall deficit. Here, we investigated shifts in wood anatomical and physiological traits of Kageneckia angustifolia, an endemic treeline species, in response to this drought *** We evaluated the xylem plasticity of three K. angustifolia populations across their natural distribution(31–35° SL) based on anatomical(vessel structure and distribution) and physiological(intrinsic water-use efficiency) variables in the tree rings. We focused on the period 2000–2020 that corresponds to before the megadrought(2000–2007),(ii) megadrought(2008–2018) and(iii) hyperdrought(2019–2020). The variables were annualized and analyzed by linear mixed-effects *** Our results provide insights to the anatomical and physiological mechanisms underlying the resilience of treeline forests to persistent droughts in central Chile. We found that the extreme drought in 2019–2020 triggered shifts in vessel size and frequency that increased hydraulic safety. These significant shifts in vessel traits occurred in parallel with a decrease in pit aperture area and an increase in water-use efficiency, further increasing the resilience of K. angustifolia to extreme drought *** Our results revealed coordinated shifts in vessel size and frequency and water-use efficiency in response to the megadrought, thereby reducing vulnerability to hydraulic failure. The apparent resilience of K. angustifolia to extreme droughts suggests that this adaptation to drought stress may incre

关键词： Dendro-anatomy Kageneckia angustifolia Xylem vulnerability Drought Climate change

1990-2020年阿根廷门多萨流域冰川变化研究

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中国农村水利水电 2024年第5期 78-86页

作者：林媛媛王飞戈文艳韩剑桥 fidel Alejandro Roig Elena María Abraham 陈昊西北农林科技大学水土保持科学与工程学院陕西杨凌712100 中国科学院水利部水土保持研究所陕西杨凌712100 Instituto Argentino de Nivología Glaciología y Ciencias Ambientales(IANIGLA-CONICET)CCT MendozaArgentina5500 Instituto Argentino de Investigaciones de Las Zonas Áridas(IADIZA-CONICET) CCT MendozaArgentina5500

冰川是南美洲阿根廷门多萨流域(33°S)重要的淡水资源,冰川作为气候变化的敏感指示器,对于理解和评估全球和区域气候变化具有重要意义。为了解门多萨流域冰川分布及变化趋势,探讨其对区域水资源和生态系统的影响,为应对气候变化提供科... 详细信息

冰川是南美洲阿根廷门多萨流域(33°S)重要的淡水资源,冰川作为气候变化的敏感指示器,对于理解和评估全球和区域气候变化具有重要意义。为了解门多萨流域冰川分布及变化趋势,探讨其对区域水资源和生态系统的影响,为应对气候变化提供科学依据,研究基于1990-2020年Landsat遥感影像,参考RGI冰川编目数据和阿根廷国家冰川清单,通过比值阈值法和人工解译法得到7期冰川边界,研究了门多萨流域冰川面积分布与变化特征。并结合TerraClimate气候数据,揭示了该区域在研究期间的气候变化趋势,探讨了区域气候变化对冰川变化的影响。结果表明:①2020年门多萨流域冰川面积为134.09±11.86 km^(2),1990-2020年冰川总体呈极显著波动下降趋势(p10 km^(2)占比最大,10 km^(2)规模冰川退缩速度最大;冰川主要分布在南坡,西北坡冰川最少,东南、东北坡冰川退缩速度最大;冰川主要分布在坡度5°~40°之间,50°~55°的冰川退缩速度最大;冰川主要分布在海拔4200~5400 m之间,<4000 m冰川退缩速率最大。③20世纪50年代末以来门多萨地区气温整体呈现极显著的上升趋势(p<0.001),研究区年均最高、最低气温每十年上升0.53、0.29℃。气温持续上升是门多萨流域冰川退缩的长期原因,降水变化是该区域冰川变化的短期原因。本研究为门多萨流域预防冰川变化导致的水资源可用性变化和地质灾害预防提供参考。

关键词：冰川变化门多萨(Mendoza) 南美洲气候变化

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Extension of Chemoprevention of Seasonal Malaria to Five Cycles and to Children from the Age of 6 to 9 Years in Africa: Analysis of Its Acceptability, Feasibility, Cost and Impact A Systematic Review

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Advances in Infectious Diseases 2024年第1期14卷 74-86页

作者： N’Kpingou Théodore Nadakou Moussiliou Noel Paraïso Ounoussa Tapha Mahamane Moustapha Lamine Jean Blaise Yobo Salifou Ibrahim Alkassoum fidel Tossou Hamidou Ramatoulaye Lazoumar Eric Omar Adehossi Regional Instutte of Public Health University of Abomey-Calavi (UAC) Ouidah Benin Pratical Institute of Public Health (IPSP) Niamey Niger Andre Salifou University of Zinder (UAS) Zinder Niger ABDOU Moumouni University of Niamey (UAM) Niamey Niger Medical and Health Researche Center (CERMES) Niamey Niger

Introduction: Seasonal Malaria Chemoprevention (SMC) aims at preventing malaria in children during the high transmission season. It has been recommended by the WHO since 2013 for children from the age of 3-59 months. However, despite the impact of this intervention, a peak in the prevalence and incidence of malaria is observed in children from the age of 5-9 years. The aim of this study is to determine from the current literature the feasibility, impact and cost-effectiveness of extending SMC to five cycles and to older children. Methods: A litterature search of PubMed/Medline, NCBI and Google scholar identified 1333 articles. After reading the titles and abstracts by two authors, 24 articles were selected and submitted for full reading. Random control studies on the extension of SMC, malaria, feasibility of SMC, impact of SMC and cost-effectiveness of SMC were selected. A total of 16 articles were included for the qualitative synthesis after excluding 8 studies. Results: Following the summary of the evidence, we conclude that the extension is feasible but will be confronted with the unavailability of older children. The intervention period coincides with field work. SMC is effective in reducing the prevalence and incidence of malaria and the parasite density in children. The financial cost of administering SMC is lower than that of treating a child suffering from malaria. Conclusion: After analysing the information, it was found that the majority of the African population supports the extension of the SMC to the number of cycles and the age group in order to alleviate the high mortality and morbidity rates among children due to malaria.

关键词： SMC Feasibility Impact Profitability and Africa

Modulation of the in vitro Oxidative Stress and Erythrocyte Cell Membrane Integrity Using Aqueous, Hydroethanolic and Ethanolic Stem-Barks Extracts of Greenwayodendron suaveolens (Engl. & Diels) Verdc

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Pharmacology & Pharmacy 2024年第3期15卷 39-61页

作者： Patrick Hervé Diboue Betote Moustapha Gambo Abdoulaye Francis Ngolsou Esther Del Florence Ndedi Moni Adeline Sabine Fanta Yadang fidel Castro Lah Weyepe Gabriel A. Agbor Nga Nnanga Maximilienne Ascension Nyegue Laboratory of Pharmacology and Drugs Discovery Centre for Research on Medicinal Plants and Traditional Medicine Institute of Medical Research and Medicinal Plants Studies Yaoundé Cameroon Laboratory of Microbiology Department of Microbiology Faculty of Science University of Yaoundé I Yaoundé Cameroon Multidisciplinary Laboratory Department of Galenical Pharmacy and Pharmaceutical Law Faculty of Medicine and Biomedical Sciences University of Yaoundé I Yaoundé Cameroon Department of Physicochemical and Pharmaceutical Sciences Faculty of Health Sciences Abdou Moumouni University Niamey Niger Department of Pharmaceutical and Biological Sciences Faculty of Medicine and Pharmaceutical Sciences University of Douala Douala Cameroon Laboratory of Pharmaceutical Technology Centre for Research on Medicinal Plants and Traditional Medicine Institute of Medical Research and Medicinal Plants Studies Yaoundé Cameroon

Pneumonia, a respiratory infection induces acute or chronic inflammation, characterized by increased activity of lymphocytes and neutrophils, thus generating oxygen-free radicals that decrease the endogenous antioxidants defence system. The aim of this experimental study focused on the capacity of nontoxic aqueous, hydroethanolic and ethanolic extracts of Greenwayodendron suaveolens (Engl. & Diels) Verdc. subsp. suaveolens to regulate free reactive species and protein inflammation generated by infectious disease. The phytochemical screenings of G. suaveolens extracts were carried out according to precipitation and colorimetric methods. The total antioxidant and flavonoid contents were determined by the Folin-Ciocalteu and Aluminium Chloride ethanolic methods. The efficiency of G. suaveolens extracts on free radicals was evaluated using DPPH•, ABTS+•, and FRAP methods. The anti-inflammatory properties of extracts were evaluated according to in vitro protein (BSA) denaturation, Proteinase Inhibitory Action, and Red Blood Cell Membrane stabilization assays. The G. suaveolens aqueous, hydroethanolic and ethanolic extracts were used for the acute toxicity assessment according to the OECD protocol. The obtained results showed the presence of flavonoids, phenols, polyphenols, tannins, anthocyanins, alkaloids, terpenoids, and sterols as secondary metabolites families in G. suaveolens extracts. The highest contents of total antioxidants and flavonoids were highlighted in the hydroethanolic extract. However, it’s the G. suaveolens aqueous extract that showed the best free radical DPPH• and ABTS+• scavenging activities (SC50) of 11.06 μg/mL and 15.16 μg/mL respectively. The highest ferric-reducing activity was found in G. suaveolens ethanolic extract with 866.23 μg EGA/mg of dry weight. The hydroethanolic extract has shown a high anti-inflammatory activity through BSA denaturation and erythrocyte membrane haemolysis with i

关键词： Greenwayodendron suaveolens Secondary Metabolites Oxidative Stress Antioxidant Activity Anti-Inflammatory Properties and Oral Acute Toxicity

Gut microbiota:a potential therapeutic target for Parkinson's disease

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Neural Regeneration Research 2021年第2期16卷 287-288页

作者： Joséfidel Baizabal-Carvallo Department of Science and Engineering University of GuanajuatoGuanajuatoMéxico

Parkinson's disease(PD)is a neurodegenerative disorder characterized by accumulation ofα-synuclein in neurons of the central nervous system(CNS).The pathogenesis of PD is complex and only partially *** evidence pointed to the basal ganglia as the source of the motor manifestations of PD,and likely the origin of the pathological *** the last two decades。

关键词： process. therapeutic pathogenesis

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