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Unravelling host-mediated effects on hemiparasitic Mexican mistletoe Psittacanthus calyculatus(DC.)*** traits linked to mutualisms with pollinators and seed dispersers

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journal of Plant Ecology 2018年第6期11卷 827-842页

作者： Sandra rodríguez-Mendieta Carlos Lara juan Francisco Ornelas Centro de Investigación en Ciencias Biológicas Universidad Autónoma de Tlaxcalakm 10.5 Carretera San Martín Texmelucan-TolucaSan Felipe IxtacuixtlaTlaxcala 90120Mexico Departamento de Biología Evolutiva Instituto de EcologíaA.C.(INECOL)Carretera antigua a Coatepec 351XalapaVeracruz 91080Mexico

Aims While the influence of mistletoe-host interactions on each other’s evolution is well-recognized,the role of interactions between mis-tletoes and its mutualistic pollinators and seed dispersers mediated by host species is relatively *** Here,we examine the effects of host species(Mexican hawthorn Crataegus mexicana DC,black cherry Prunus serotina Ehrh.,leather-leaf Mexican oak Quercus crassipes Bonpl.)on flower morphology,nectar production,pollinator visitation rate and female reproduct-ive fitness in hemiparasitic Mexican mistletoe Psittacanthus caly-culatus(DC.)***(Loranthaceae)populations at three different *** first measured the lengths of corolla,style,stamen,exerted stamen and anther,the length and width of the ovary and nectar availability for mistletoe flowers in natural ***,we evaluated flower visitation and measured(length and width)and weighed the fruits and its seeds of mistletoes growing on each of the three host ***,we evaluated the effects of host species,location and flower traits on fruit or seed size variation(both as proxies of reproductive fitness).Important Findings We found mistletoes growing on natural hosts *** and *** produced larger flowers,fruits and seeds than mistle-toes on cultivated ***,these differences varied across *** amount of available nectar and hummingbird vis-itation rates in flowers of mistletoes on *** was higher at the three sites than in flowers of mistletoes on *** or *** effects of host species,study site and floral trait covariates affected significantly all fitness measures,indicating that mistletoes’reproductive fitness is affected differently depending on the host species and their site of *** host-associated differ-ences in reproduction might have implications for interactions with mutualistic vectors.

关键词： floral and fruit traits hosts hummingbirds local host adaptation mistletoes nectar parasitic plants pollination Psittacanthus

Decoding the genetic program of micronucleus formation: linking chromosomal instability to human disease

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Signal Transduction and Targeted Therapy 2024年第7期9卷 2840-2842页

作者： jörg Fahrer Division of Food Chemistry and Toxicology Department of ChemistryRPTU Kaiserslautern-Landau67663 KaiserslauternGermany

A recent study by Adams and colleagues published in Nature unveiled more than one hundred genes that are involved in micronucleus formation,1 which is a biomarker for genomic instability and associated with aging,cancer,and other disorders.2 As an outstanding achievement,the authors identified DSCC1(DNA Replication And Sister Chromatid Cohesion 1)as a critical gene protecting against early developmental defects,genomic instability,reduced proliferative capacity,cohesinopathy-related phenotypes,and tumor development in vivo.

关键词： chromosomal linking Replication

A Maschke Type Theorem for Weak Hopf Algebras

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Acta Mathematica Sinica,English Series 2008年第12期24卷 2065-2080页

作者： j.N.ALONSOLVAREZ j.M.FERNNDEZVILABOA R.GONZLEZrodríguez A.B.rodríguezRAPOSO Departamento de Matemáticas Universidad de Vigo. Lagoas-Marcosende Vigo. E-36200 Spain Departamento de lxebra. Universidad de Santiago de Compostela Santiago de Compostela. E-15771 Spain Departamento de Matemdtica Aplicada Ⅱ. Universidad de Vigo. Lagoas-Marcosende Vigo. E-36310 Spain Departamento delxebra Universidad de Santiago de CompostelaSantiago de Compostela E-15771 Spain

In this paper, we give a necessary and sufficient condition for a comodule algebra over a weak Hopf algebra to have a total integral, thus extending the classical theory developed by Doi in the Hopf algebra setting. Also, from these results, we deduce a version of Maschke＇s Theorem for （H, B）-Hopf modules associated with a weak Hopf algebra H and a right H-comodule algebra B.

关键词： Monoidal category weak Hopf algebra Hopf modules Maschke Theorem

Effects of cellulase and xylanase enzymes mixed with increasing doses of Salix babylonica extract on in vitro rumen gas production kinetics of a mixture of corn silage with concentrate

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journal of Integrative Agriculture 2015年第1期14卷 131-139页

作者： Abdelfattah Z M Salem German Buendía-rodríguez Mona M M Elghandour María A Mariezcurrena Berasain Francisco j Pea jiménez Alberto B Pliego juan C V Chagoyán María A Cerrillo Miguel A rodríguez Faculty of Veterinary Medicine and Animal Science Autonomous University of the State of Mexico National Center of Disciplinary Research in Animal Physiology and Improvement INIFAP Ajuchitlán Institute of Agricultural Sciences Autonomous University of HidalgoEx-Hda. of Aquetzalpa Faculty of Veterinary Medicine and Animal Science Juárez University of the Durango State

An in vitro gas production （GP） technique was used to investigate the effects of combining different doses of Salix babylonica extract （SB） with exogenous fibrolytic enzymes （EZ） based on xylanase （X） and cellulase （C）, or their mixture （XC; 1：1 v/v） on in vitro fermentation characteristics of a total mixed ration of corn silage and concentrate mixture （50：50, w/w） as substrate. Four levels of SB （0, 0.6, 1.2 and 1.8 mL g-1 dry matter （DM）） and four supplemental styles of EZ （1 μL g-1 DM; control （no enzymes）, X, C and XC （1：1, v/v） were used in a 4×4 factorial arrangement. In vitro GP （mL g-1 DM） were recorded at 2, 4, 6, 8, 10, 12, 24, 36, 48 and 72 h of incubation. After 72 h, the incubation process was stopped and supernatant pH was determined, and then filtered to determine dry matter degradability （DMD）. Fermentation parameters, such as the 24 h gas yield （GY24）, in vitro organic matter digestibility （OMD）, metabolizable energy （ME）, short chain fatty acid concentrations （SCFA）, and microbial crude protein production （MCP） were also estimated. Results indicated that there was a SBxEZ interaction （P〈0.0001） for the asymptotic gas production （b）, the rate of gas production （c）, GP from 6 to 72 h, GP2 （P=0.0095）, and GP4 （P=0.02）. The SB and different combination of enzymes supplementation influenced （P〈0.001） in vitro GP parameters after 12 h of incubation; the highest doses of SB （i.e., 1.8 mL g-1 DM）, in the absence of any EZ, quadratically increased （P〈0.05） the initial delay before GP begins （L） and GP at different incubation times, with lowering b （quadratic effect, P〈0.0001 ） and c （quadratic effect, P〈0.0001 ; linear effect, P=0.0018）. The GP was the lowest （P〈0.05） when the highest SB level was combined with cellulose. There were SBxEZ interactions （P〈0.001） for OMD, ME, the partitioning factor at 72 h of incubation （PF72）, GY24, SCFA, MCP （P=0.0143）, and pH （P=0.0008）. The OMD, ME, GY24 and SCFA with supplementation of SB extract at 1.8 mL g-1 DM were h

关键词： cellulase degradability gas production Salix babylonica xylanase

Necrotic enteritis and antibiotic-free production of broiler chickens:Challenges in testing and using alternative products

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Animal Nutrition 2024年第01期16卷 288-298页

作者： Robert j.Moore School of Science RMIT University

The global trend towards raising broiler chickens without the use of in-feed antibiotics(IFAs) means that there is an ongoing need to develop alternative treatments capable of delivering the benefits that IFAs previously provided. IFAs supported the productivity performance of chickens and played a key role in maintaining their health. Necrotic enteritis(NE) is an important disease of broilers that affects health,productivity, and welfare, and was previously well controlled by IFAs. However, with the reduction in IFA use, NE is resurgent in some countries. Vaccines and various feed additives, including pre-, pro-, and postbiotics, phytobiotics, fatty acids, and phage therapies have been introduced as alternative methods of NE control. While some of these feed additives have specific activity against the NE pathogen, Clostridium perfringens, most have the more general goal of reinforcing gut health. Extensive reviews of the effects of many of these feed additives on gut health have been published recently. Hence, rather than cover previously well reviewed areas of research this review focuses on the challenges and pitfalls in undertaking experimental assessment of alternative NE treatments and translating laboratory research to real world commercial production settings. The review is based on the author's particular experience,reading, thoughts, and analysis of the available information and inevitably presents a particular understanding that is likely to be at odds with others thinking on these issues. It is put forward to stimulate thinking and discussion on the issues covered.

关键词： Necrotic enteritis Clostridium perfringens Vaccines Feed additive Farm management

Effect of heat treatment on the mechanical and biocorrosion behaviour of two Mg-Zn-Ca alloys

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journal of Magnesium and Alloys 2022年第2期10卷 581-595页

作者： N.Pulido-González P.Hidalgo-Manrique S.García-rodríguez B.Torres j.Rams Departamento de Matemática Aplicada Ciencia e Ingeniería de Materiales y Tecnología ElectrónicaESCETUniversidad Rey Juan CarlosC/Tulipán s/nMóstolesMadrid28933Spain

The effect of heat treatment on the mechanical and biocorrosion behaviour of the Mg-1 wt.%Zn-1 wt.%Ca(ZX11)and Mg-3 wt.%Zn-0.4 wt.%Ca(ZX30)alloys was *** this purpose,three-point bending tests as well as electrochemical and immersion tests in Hank’s solution were performed on both alloys in four different thermal conditions:as-cast,solution-treated,peak-aged and *** examinations revealed that the as-cast ZX11 and ZX30 alloys exhibit a microstructure composed ofα-Mg grains separated by large Mg_(2)Ca and Ca_(2)Mg_(6)Zn_(3) particles and by large Ca_(2)Mg_(6)Zn_(3) particles,*** solution treatment,the Ca_(2)Mg_(6)Zn_(3) precipitates at the grain boundaries(GBs)are fully dissolved in the ZX11 alloy,but mainly redistributed to form a more connected configuration in the ZX30 alloy,showing a poor age-hardening ***,after solution-treatment,galvanic corrosion and corrosion rate decreases in the former,but increases in the *** peak-aged condition displays the highest corrosion rate for both alloys,maybe due to an excessive number density of fine Ca_(2)Mg_(6)Zn_(3) particles acting as cathodic ***,the over-aged condition shows the lowest corrosion rate for the ZX11 alloy and a very similar one to that of the as-cast sample for the ZX30 *** ZX11 alloy shows generally better biocorrosion behaviour than the ZX30 alloy to its lower content in the Ca_(2)Mg_(6)Zn_(3) phase and thus reduced galvanic *** Mg_(2)Ca phase present in the studied ZX11 alloy has been proved to exhibit an increased corrosion potential,which has been related to an observed enrichment with Zn.

关键词： Magnesium alloys Biodegradable implants Heat treatment Microstructure Mechanical properties Corrosion

Drought and Spatiotemporal Variability of Forest Fires Across Mexico

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Chinese Geographical Science 2018年第1期28卷 25-37页

作者： Pompa-García MARíN Camarero j.jULIO rodríguez-Trejo DANTE ARTURO Vega-Nieva DANIEL jOSE Facultad de Ciencias Forestales Universidad Juarez del Estado de Durango Durango 34120 MExico Instituto Pirenaico de Ecologia IPE-CSIC 50059 Spain Divisian de Ciencias Forestales Universidad Autonoma Chapingo Chapingo 56230 MExico

Understanding the spatiotemporal links between drought and forest fire occurrence is crucial for improving decision-making in fire management under current and future climatic conditions. We quantified forest fire activity in Mexico using georeferenced fire records for the period of 2005–2015 and examined its spatial and temporal relationships with a multiscalar drought index, the Standardized Precipitation-Evapotranspiration Index(SPEI). A total of 47975 fire counts were recorded in the 11-year long study period, with the peak in fire frequency occurring in 2011. We identified four fire clusters, i.e., regions where there is a high density of fire records in Mexico using the Getis-Ord G spatial statistic. Then, we examined fire frequency data in the clustered regions and assessed how fire activity related to the SPEI for the entire study period and also for the year 2011. Associations between the SPEI and fire frequency varied across Mexico and fire-SPEI relationships also varied across the months of major fire occurrence and related SPEI temporal scales. In particular, in the two fire clusters located in northern Mexico(Chihuahua, northern Baja California), drier conditions over the previous 5 months triggered fire occurrence. In contrast, we did not observe a significant relationship between drought severity and fire frequency in the central Mexico cluster, which exhibited the highest fire frequency. We also found moderate fire-drought associations in the cluster situated in the tropical southern Chiapas where agriculture activities are the main causes of forest fire occurrence. These results are useful for improving our understanding of the spatiotemporal patterns of fire occurrence as related to drought severity in megadiverse countries hosting many forest types as Mexico.

关键词： cluster drought forest fires geostatistics spatial clusters Standardised Precipitation-Evapotranspiration Index (SPEI)

Association of accelerometer-derived step volume and intensity with hospitalizations and mortality in older adults:A prospective cohort study

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journal of Sport and Health Science 2022年第5期11卷 578-585页

作者： Asier Manas Borja del Pozo Cruz Ulf Ekelund joséLosa Reyna Irene rodríguez Gómez joséAntonio Carnicero Carreno Leocadio rodríguez Manas Francisco j.García García Ignacio Ara GENUD Toledo Research Group University of Castilla-La ManchaToledo 45071Spain CIBER of Frailty and Healthy Aging(CIBERFES) Madrid 28029Spain Motivation and Behaviour Research Program Institute for Positive Psychology and EducationFaculty of Health SciencesAustralian Catholic UniversitySydneyNSW 2060Australia Department of Sports Medicine Norwegian School of Sport SciencesOslo 0806Norway Department of Chronic Diseases and Ageing Norwegian Institute of Public HealthOslo 0473Norway Geriatric Department Hospital Virgen del ValleToledo 45071Spain Geriatric Department Hospital Universitario de GetafeGetafe 28905Spain

Purpose:This study aimed to examine the associations of accelerometer-derived steps volume and intensity with hospitalizations and all-cause mortality in older ***:This prospective cohort study involved 768 community-dwelling Spanish older adults(78.8±4.9 years,mean±SD;53.9% females)from the Toledo Study for Healthy Aging(2012-2017).The number of steps per day and step cadence(steps/min) were derived from a hip-mounted accelerometer worn for at least 4 days at *** were followed-up over a mean period of 3.1 years for hospitalization and 5.7 years for all-cause *** proportional hazards regression models were used to estimate the individual and joint associations between daily steps and stepping intensity with hospitalizations and all-cause ***:Included participants walked 5835± 3445 steps/day with an intensity of 7.3± 4.1 steps/*** adjusting for age,sex,body mass index(BMI),education,income,marital status and comorbidities,higher step count(hazard ratio(HR)=0.95,95% confidence interval(95%CI:0.90-1.00,and HR=0.87,95%CI:0.81-0.95 per additional 1000 steps) and higher step intensity(HR=0.95,95%CI:0.91-0.99,and HR=0.89,95%CI:0.84-0.95 per each additional step/min) were associated with fewer hospitalizations and all-cause mortality risk,*** to the group having low step volume and intensity,individuals in the group having high step volume and intensity had a lower risk of hospitalization(HR=0.72,95%CI:0.52-0.98) and all-cause mortality(HR=0.60,95%CI:0.37-0.98).Conclusion:Among older adults,both high step volume and step intensity were significantly associated with lower hospitalization and all-cause mortality *** step volume and intensity may benefit older people.

关键词： Aging Follow-up Objective Physical activity Walking

Soil Conservation Measures in Rainfed Olive Orchards in South-Eastern Spain: Impacts of Plant Strips on Soil Water Dynamics

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Pedosphere 2009年第4期19卷 453-464页

作者： V. H. DURN ZUAZO C. R. rodríguez PLEguezUELO L. ARROYO PANADERO A. MARTíNEZ RAYA j. R. FRANCIA MARTíNEZ B. CRCELES rodríguez Instituto de Investigación y Formación Agraria y Pesquera IFAPA Centro Camino de Purchil

Sloping and mountainous olive production systems are widespread, occupying large parts of the Mediterranean landscape prone to water erosion. Soil erosion, runoff, and soil water content patterns over a three-year period were monitored in erosion plots on a mountainside with rainfed olive （Olea europaea cv. Picual） trees under： 1） non-tillage with barley strips of 4 m width （BS）; 2） non-tillage with native vegetation strips of 4 m width （NVS）; and 3） non-tillage without plant strips （NT）. The erosion plots, located in Lanjaron （Granada, south-eastern Spain）, on a 30% slope, were 192 m2 in area. For assessing soil water dynamics in real-time and near-continuous soil water content measurements, multisensor capacitance probes were installed in the middle of plant strips and beneath the olive tree at five soil depths （10, 20, 30, 50, and 100 cm）. The highest erosion and runoff rates were measured under NT, with a mean of 17.3 Mg ha-1 year-1 and 140.0 mm year-1, respectively, over the entire study period. The BS and NVS with respect to the NT reduced erosion by 71% and 59% and runoff by 95% and 94%, respectively. In general, greater available soil water content was found under BS than NVS and NT, especially beneath the olive tree canopies. These results supported the recommendation of non-tillage with barley strips in order to reduce erosion and to preserve soil water for trees in traditional mountainous olive-producing areas, where orchards cover vast tracts of land.

关键词： farming systems native plants runoff soil erosion