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Advances in Polar Science 2014年第2期25卷 92-96页

作者： Daniela n. Correa-Llantén Maximiliano J. Amenábar Patricio A. Mu?oz María T. Monsalves Miguel E. Castro Jenny M. Blamey fundación científicay cultural biociencia José Domingo Ca?as 2280 Santiago 8340457 Chile

A gram-positive, rod-shaped, aerobic, thermo-acidophilic bacterium CC2 （optimal temperature 55℃ and pH 4.0）, belonging to the genus Alicyclobacillus was isolated from geothermal soil collected from ＂Cerro Caliente＂, Deception Island, Antarctica. Owing to the harsh environmental conditions found in this territory, microorganisms are exposed to conditions that trigger the generation of reactive oxygen species （ROS）. They must have an effective antioxidant defense system to deal with this oxidative stress. We focused on one of the most important enzymes： superoxide dismutase, which was partially purified and characterized. This study presents the first report of a thermo-acidophilic bacterium isolated from Deception lsland with a thermostable superoxide dismutase （SOD）.

关键词： Antarctica thermo-acidophile SOD geothermal Deception Island

Effects of fertilization on radial growth of Pinus pinea explored hourly using dendrometers

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Ecological Processes 2024年第1期 25-39页

作者： Verónica Loewe-Mu?oz Rodrigo del Río Millar Claudia Delard Rodriguez Mónica Balzarini Chilean Forest Institute (InFOR) Metropolitan Office Centro nacional de Excelencia Para la Industria de la Madera(CEnAMAD) Pontificia Universidad Católica de Chile Consejo nacional de Investigaciones científicas y Técnicas (COnICET ) Universidad Nacional de Córdoba Ciudad Universitaria

Background Stone pine(Pinus pinea), a drought-resistant species, has significant socio-economic benefits and increasing interest for the establishment of productive plantations in several countries, especially in a climate change context. Monitoring hourly stem diameter variations contributes to the understanding of the tree-growth response to changes in environmental conditions and management. By monitoring the diameter expansion of tree stems, high-resolution band dendrometers were used to study the development of adult trees growing in a semi-arid coastal environment of central Chile under fertilized and non-fertilized soil conditions through the span of a *** Short cycles(n fertilized and non-fertilized trees(6 and 4, respectively), whereas long cycles(> 28 h) occurred at a higher frequency in fertilized trees(16 vs 6). Most of the circadian cycles were regular(24 ± 3 h). The longest cycle duration(59 h) was observed in fertilized trees during spring. In all seasons, each phase of the circadian cycle, especially during the stem diameter increment phase(P3, irreversible growth), started earlier in fertilized than in control trees. P3 duration was significantly longer in fertilized than in control trees in springtime. The maximum shrinkage(P1) was observed in summer for both treatments. Stem diameter increased faster in fer-tilized than in control trees throughout the year, with the highest accumulation occurring in spring and the lowest in autumn. The daily variability pattern showed lower growth under high temperature across *** This study highlights the importance of fertilization in enhancing stone pine diameter growth. This cultural practice should be further explored to contribute to the mitigation of climate change effects in semi-arid environments.

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Purification and characterization of a thermostable glutamate dehydrogenase from a thermophilic microorganism from Deception Island, Antarctica

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Advances in Polar Science 2016年第1期27卷 8-13页

作者： Patricio A. Flores M. Freddy Boehmwald Jenny M. Blamey A. fundacion cientifica y cultural biociencia Santiago Chile Jose Domingo Cafias 2280 Santiago Chile 775-0132 Universidad de Santiago Santiago Chile

Glutamate dehydrogenase （GDH） catalyzes the oxidative deamination of glutamate to a-ketoglutarate and ammonium ions. Currently the determination of ammonium and glutamate is carried out using a bovine GDH enzyme, which lacks optimal thermostability for long term storage at room temperature. From samples of Deception Island, Antarctica, we obtained the thermophilic bacteria PID 15 belonging to the Bacillus genera with high GDH specific activity. This new enzyme exhibited nAD＋ dependent activity and no activity was observed when nADP＋ was used. This enzyme shows a specific activity of 4.7 ***-1 for the oxidative deamination reaction and 15.4 U·mg-1 for the reduction of a-ketoglutarate. This enzyme has an optimum temperature of 65℃ and pH of 8.5 for the oxidative deamination. For the reduction of a-ketoglutarate, the optimum temperature is 60℃, with a pH of 8.0. One of the most important characteristics of this enzyme is its ability to retain more than 60% of its activity when it is incubated for 8 h at 65℃. The enzyme is also able to retain full activity when it is incubated for 48 d at 4℃ and over 80% of its activity when it is incubated at 25℃. Characterization of its kinetics suggests that it primarily catalyzes the formation of α-ketoglutarate. This enzyme has an important biological role in the catabolism of glutamate and may have some interesting biotechnological applications based on its thermostable properties.

关键词： Antarctica glutamate dehydrogenase thermophile

Medicinal chemistry strategies towards the development of non-covalent SARS-CoV-2 Mpro inhibitors

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Acta Pharmaceutica Sinica B 2024年第1期14卷 87-109页

作者： Letian Song Shenghua Gao Bing Ye Mianling Yang Yusen Cheng Dongwei Kang Fan Yi Jin-Peng Sun Luis Menéndez-Arias Johan neyts Xinyong Liu Peng Zhan Department of Medicinal Chemistry Key Laboratory of Chemical Biology(Ministry of Education)School of Pharmaceutical SciencesCheeloo College of MedicineShandong UniversityJinan 250012China Shenzhen Research Institute of Shandong University Shenzhen 518057China The Key Laboratory of Infection and Immunity of Shandong Province Department of PharmacologySchool of Basic Medical SciencesShandong UniversityJinan 250012China Key Laboratory Experimental Teratology of the Ministry of Education Department of Biochemistry and Molecular BiologySchool of Basic Medical SciencesCheeloo College of MedicineShandong UniversityJinan 250012China Centro de Biologı´a Molecular“Severo Ochoa”(Consejo Superior de Investigaciones cientı´ficas&Autonomous University of Madrid) Madrid 28049Spain KU Leuven Department of Microbiology and ImmunologyRega Institute for Medical ResearchLaboratory of Virology and ChemotherapyLeuven 3000Belgium

The main protease(M^(pro))of SARS-CoV-2 is an attractive target in anti-COVID-19 therapy for its high conservation and major role in the virus life *** covalent M^(pro)inhibitor nirmatrelvir(in combination with ritonavir,a pharmacokinetic enhancer)and the non-covalent inhibitor ensitrelvir have shown efficacy in clinical trials and have been approved for therapeutic *** antiviral drugs are needed to fight the pandemic,while non-covalent M^(pro)inhibitors could be promising alternatives due to their high selectivity and favorable *** non-covalent M^(pro)inhibitors with desirable properties have been developed based on available crystal structures of M^(pro).In this article,we describe medicinal chemistry strategies applied for the discovery and optimization of non-covalent M^(pro)inhibitors,followed by a general overview and critical analysis of the available *** viewpoints and insights into current strategies for the development of non-covalent M^(pro)inhibitors are also discussed.

关键词： COVID-19 SARS-CoV-2 Main protease non-covalent inhibitors Medicinal chemistry strategies

Plant nitrogen Metabolism: Balancing Resilience to nutritional Stress andAbiotic Challenges

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Phyton-International Journal of Experimental Botany 2024年第3期93卷 581-609页

作者： Muhammad Farhan Manda Sathish Rafia Kiran Aroosa Mushtaq Alaa Baazeem Ammarah Hasnain Fahad Hakim Syed Atif Hasan naqvi Mustansar Mubeen Yasir Iftikhar Aqleem Abbas Muhammad Zeeshan Hassan Mahmoud Moustafa Department of Plant Pathology Faculty of Agricultural Sciences&TechnologyBahauddin Zakariya UniversityMultan60800Pakistan Centro de Investigación de Estudios Avanzados del Maule(CIEAM) Vicerrectoría de Investigación y PostgradoUniversidad Católica del MauleTalca3460000Chile College of Food Science and nutritional Engineering China Agricultural UniversityBeijingChina Department of Biology College of ScienceTaif UniversityP.O.Box 11099Taif21944Saudi Arabia Department of Biotechnology Faculty of Biological SciencesLahore University of Biological and Applied SciencesLahorePakistan Department of Plant Pathology College of AgricultureUniversity of SargodhaSargodha40100Pakistan Department of Agriculture and Food Technology Karakorum International UniversityGilgitPakistan Department of Biology Faculty of ScienceKing Khalid UniversityAbhaSaudi Arabia

Plant growth and resilience to abiotic stresses,such as soil salinity and drought,depend intricately on nitrogen *** review explores nitrogen’s regulatory role in plant responses to these challenges,unveiling a dynamic interplay between nitrogen availability and abiotic *** the context of soil salinity,a nuanced rela-tionship emerges,featuring both antagonistic and synergistic interactions between salinity and nitrogen ***-induced chlorophyll depletion in plants can be alleviated by optimal nitrogen supplementation;however,excessive nitrogen can exacerbate salinity *** delve into the complexities of this interaction and its agri-cultural ***,a vital element within essential plant structures like chloroplasts,elicits diverse responses based on its *** review comprehensively examines manifestations of nitrogen deﬁciency and toxicity across various crop types,including cereals,vegetables,legumes,and ***,we explore the broader consequences of nitrogen products,such as n_(2)O,nO_(2),and ammonia,on human ***-ing the intricate relationship between nitrogen and salinity,especially chloride accumulation in nitrate-fed plants and sodium buildup in ammonium-fed plants,is pivotal for optimizing crop nitrogen ***,prudent nitrogen use is essential,as overapplication can exacerbate nitrogen-related *** Use Efﬁ-ciency(nUE)is of paramount importance in addressing salinity challenges and enhancing sustainable crop *** this goal requires advancements in crop varieties with efﬁcient nitrogen utilization,pre-cise timing and placement of nitrogen fertilizer application,and thoughtful nitrogen source selection to mitigate losses,particularly urea-based fertilizer *** review article delves into the multifaceted world of plant nitrogen metabolism and its pivotal role in enabling plant resilience to nutritional stress and abiotic chall

关键词： Synthetic nitrogen nitrogen signaling sustainable agriculture eutrophication ammonium nitrate

Extensive pollen immigration and no evidence of disrupted mating patterns or reproduction in a highly fragmented holm oak stand

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Journal of Plant Ecology 2014年第4期7卷 384-395页

作者： Joaquín Ortego Raúl Bonal Alberto Muñoz JoséMiguel Aparicio Grupo de Investigación de la Biodiversidad Genética y cultural Instituto de Investigación en Recursos Cinegéticos-IREC(CSICUCLMJCCM)Ronda de Toledo s/nE-13005 Ciudad RealSpain Departamento de Ecología Evolutiva Museo Nacional de Ciencias Naturales(CSIC)C/JoséGutiérrez Abascal 2E-28006 MadridSpain Departamento de Didáctica de las Ciencias Experimentales Facultad de EducaciónUniversidad Complutense de MadridC/Rector Royo Villanova s/nE-28040 MadridSpain Centre de Recerca Ecològica i Aplicacions Forestals(CREAF) Cerdanyola del VallèsE-08193 BarcelonaSpain

Aims Forest fragmentation and reduced tree population densities can poten-tially have negative impacts on mating patterns,offspring genetic diversity and reproductive *** aim of the present study is to test these hypotheses comparing an extremely fragmented,low tree density(~0.02 trees/ha)holm oak(Quercus ilex l.)stand from Central spain with a nearby high tree density stand(~50 trees/ha).Methods We genotyped adult trees and seeds from the low-density stand(436 seeds from 15 families)and the high-density stand(404 seeds from 11 families)using nine microsatellite *** these data,we performed paternity analyses,determined pollen flow,mating patterns and pollen pool structure,and estimated progeny genetic diversity in both *** also studied seed set and production and performed a pollen supplementation experiment to determine whether reduced tree density has limited foreign pollen *** Findings We have found extensive pollen immigration(>75%)into the low tree density stand and monte Carlo simulations revealed that pollen moves larger distances than expected from null models of random *** patterns and differentiation of pollen pools were similar in the high-density stand and the low-density stand but we found higher inter-annual differentiation of pollen pools in the *** genetic diversity and self-fertilization rates did not dif-fer between the low-density stand and the high-density *** set rates were significantly lower in the low-density stand than in the high-density stand and experimental cross-pollen supplementation evidenced that foreign pollen availability is indeed a limiting factor in the ***,seed crops did not differ between the low-density stand and the high-density stand,indicating that limitation of foreign pollen is not likely to be of great concern in terms of reduced seed production and potential *** forest regeneration due to other ecological and human fac

关键词： forest fragmentation genetic diversity paternity analyses pollen dispersal pollen pool structure selfing tree density

Ecological perspectives on variable retention forestry

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Ecological Processes 2020年第1期9卷 139-144页

作者： Guillermo J.Martínez Pastur Ilkka Vanha-Majamaa Jerry F.Franklin Centro Austral de Investigaciones científicas(CADIC) Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET)Houssay 200(9410)UshuaiaTierra del FuegoArgentina natural Resources Institute Finland(Luke) Latokartanonkaari 9FI-00790 HelsinkiFinland School of Environmental and Forest Science University of WashingtonSeattleWA 98195USA

Forest management globally affects the ecosystem services,especially those related to ecosystem functioning and biodiversity conservation,by altering forest structure and *** degree of alteration was related to the intensity and type of harvesting;therefore,the major silvicultural challenge is to develop alternatives to mitigate climate change and maintain forest functions and biodiversity while also providing acceptable levels of timber *** retention forestry(VRF)is a highly flexible concept,with continuity of forest cover,structure,function,and species composition,thereby supporting multiple economic,environmental,and cultural *** special issue provides an overview of the concepts and applications related to VRF implementation around the *** shows that VRF has been applied globally for several decades,with varying levels and retention types,depending on local conditions and the economic importance of *** challenges of VRF seem to differ to some extent on different continents,yet the general aims have been accepted in most of the *** has been successful in mitigating many effects of intensive harvesting,though in some forests of the world,the retention levels are too low to maintain acceptable levels of biodiversity and ecosystem *** conclude that an active collaboration between scientists and forest practitioners is needed to realize all of the opportunities provided by VRF in solving global forestry-related issues.

关键词： Sustainable forestry Biodiversity conservation Timber production Aggregated retention Dispersed retention Forest certification Prescribed burning Synergies and trade-offs

Improving the knowledge of plant potential biodiversity-ecosystem services links using maps at the regional level in Southern Patagonia

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Ecological Processes 2021年第1期10卷 709-734页

作者： Yamina Micaela Rosas Pablo L.Peri María Vanessa Lencinas Romina Lasagno Guillermo J.Martínez Pastur Laboratorio de Recursos Agroforestales Centro Austral de Investigaciones Científicas(CADIC)Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET)Houssay 2009410 UshuaiaTierra del FuegoArgentina. Instituto nacional de Tecnología Agropecuaria(InTA) Universidad Nacional de la Patagonia Austral(UNPA)Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET)CC 3329400 Río GallegosSanta CruzArgentina. Instituto nacional de Tecnología Agropecuaria(InTA) CC 3329400 Río GallegosSanta CruzArgentina.

Background:Biodiversity supports multiple ecosystem services,whereas species loss endangers the provision of many services and affects ecosystem resilience and resistance *** increase of remote sensing techniques allows to estimate biodiversity and ecosystem services supply at the landscape level in areas with low available data(*** Patagonia).This paper evaluates the potential biodiversity and how it links with ecosystem services,based on vascular plant species across eight ecological *** also evaluated the habitat plant requirements and their relation with natural gradients.A total of 977 plots were used to develop habitat suitability maps based on an environmental niche factor analysis of 15 more important indicator species for each ecological area(n=53 species)using 40 explanatory ***,these maps were combined into a single potential biodiversity map,which was linked with environmental variables and ecosystem services *** comparisons,data were extracted and compared through analyses of ***:The plant habitat requirements varied greatly among the different ecological areas,and it was possible to define groups according to its specialization and marginality *** potential biodiversity map allowed us to detect coldspots in the western mountains and hotspots in southern and eastern *** biodiversity was associated to higher temperatures and normalized difference vegetation index,while lower biodiversity was related to elevation and *** biodiversity was closely associated with supporting and provisioning ecosystem services in shrublands and grasslands in the humid steppe,while the lowest values were related to cultural ecosystem services in nothofagus ***:The present study showed that plant species present remarkable differences in spatial distributions and ecological requirements,being a useful proxy for potential biodiversity *** biodiversity values

关键词： Habitat suitability Environmental variables Ecosystem functions Conservation management Ecosystem services Landscape modelling

Challenges at the early stages of the environmental licensing procedure and potential contributions from geomorphology

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Geoscience Frontiers 2021年第6期12卷 36-45页

作者： Cristina I.Pereira Celene B.Milanes Rafael Sarda Benjamin Cuker Camilo M.Botero Coastal Systems Research Group Playas Corporation Ltda.BogotáColombia Corporación para el Desarrollo Sostenible del Urabá–CORPOURABA Barrio ManzanaresCl.92No 98-39ApartadóColombia Civil and Environmental Department Universidad de la CostaBarranquillaColombia Centro de Estudios Avanzados de Blanes Consejo Superior de Investigaciones CientíficasCEAB-CSICSpain Department of Marine and Environmental Science Hampton UniversityHamptonVA 23668USA University Sergio Arboleda School of LawSanta MartaColombia

Defining impact significance is the main technical task that influences decision-making during the Environmental Licensing Procedure(ELP).The ELP begins with screening to determine potentially significant impacts of the proposed *** then follows to address any interventions deemed worthy of attention in the production of an Environmental Impact Assessment(EIA).This will include consideration of relevant landforms and geomorphological ***,preliminary assessments of environmental impacts often lack the scientific robustness to procure substantive and transactive *** review presents an examination of the established practices of screening and scoping while highlighting the foremost challenges to improve the technical grounds of the *** analysis of screening and scoping practices stresses the need for novel methods that ensure the sequential reasoning between their criteria while improving the preliminary evaluation of impact *** the inherent subjectivity of discretionary judgment requires scientific methodologies that acknowledge the interaction between the natural system and human interventions,which has been addressed by geomorphological *** knowledge consolidated in this review opens the gate to explore the compatibility between the United nations strategy of Ecosystem Approach(EA)with the ELP through a novel geomorphological interpretation of the ***,this diagnosis demonstrate that screening and scoping practices would benefit from reliable methods that balance the precautionary principle with the efficient character required in the ELP.

关键词： EIA effectiveness Screening and scoping practices Landforms Geomorphological processes Ecosystem approach

The Children’s Faecal Matter Structure Is Built by Their Parents

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Open Journal of Epidemiology 2019年第1期9卷 64-74页

作者： Eduard Cueto Rua Ricardo Wright Cecilia Zubiri Luciana Guzmán Claudia Losada M. Inés Urrutia María T. Gonzalez Ricardo Drut Mariela Espósito norberto Recalde Jorge Fiad Ignacio Goni natalia Belén María Cristina Arregui Facultad de Ciencias Médicas Universidad Nacional de La Plata La Plata Argentina Comisión de Investigación científica de la Provincia de Buenos Aires Buenos Aires Argentina Pediatric Hospital “Sor María Ludovica” La Plata Argentina Universidad nacional de La Plata La Plata Argentina Consultant in Pediatrics Mar del Plata City Argentina Dolores City Argentina

Introduction: Humans have gone through physical changes over the last 4 million years. The mouth, however, has not changed teeth quantity or quality. Eight incisors for fruits, vegetables and tubers;four little canines for little animals;eight premolars and twelve flat molars are used for crushing these foods, especially whole grains and legumes. The teeth crushing foods are the first step in the building of faecal matter. Foods are selected mostly according to cultural guidelines than to biological needs. The patterns of consumption are induced by the publicity of industrialized or processed foods. Material and Methods: This study design was observational, analytical, correlational, transversal and prospective. One thousand children (0 - 12 years old) were questioned in order to learn about the relationship between Weekly Eating Frequency (WEF) and Faecal Matter (FM) characteristics. The FM was classified as soft, normal or hard and the outcome was expressed as Dry Faecal Residue (DFR). The WEF and Weekly Bowel Movement Frequency (WBMF) were determined and tabulated according to times per week. Environmental factors, parents’ education level and children’s birth order were examined. Results: There was a strong association between DFR, WBMF and WEF. Environment and education level did not play a key role although birth order did matter. Conclusions: Fibre-free foods (dairies, meats, flours and sweeties or sodas) increased DFR. Foods containing fibre from vegetables decreased DFR, which in turn contributed to the WBMF. Lowest DFR was observed in children under Exclusive Breastfeeding (EB). Distant last-born children had higher DFR. Comments: Daily examples support these results and it is clear that children’s FM is built by their parents. We encourage parents to follow the “mouth nature” rather than the “advertisements nature”.

关键词： Bowel Movement Frequency Constipation Culture Faecal Matter Foods