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Shade shelters increase survival and photosynthetic performance of oak transplants at abandoned fields in semi-arid climates

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Journal of Forestry Research 2013年第1期24卷 23-28页

作者： Claudia González-Salvatierra Ernesto Iván Badano Joel flores Juan Pablo Rodas División de Ciencias Ambientales Instituto Potosino de Investigación Científica y TecnológicaA.C.Camino a la Presa San José 2055C.P. 78216San Luis PotosíS.L.P.México.

Forest restorations conducted in semiarid, seasonally dry climates must deal with the intense drought stress that affects tree seedlings during the dry season. Although this water deficit is the most commonly invoked source of mortality for seedlings, several other environmental factors may also preclude survival of transplants. For instance, it has been widely reported that excessive light reduces the efficiency of the photosynthetic apparatus, hence decreasing plant survival, but most seedling transplants in deforested areas are conducted under these light conditions. This study is focused in determining whether excessive light affects the photosynthetic performance and survival of Quercus coccolobifolia, a mexican oak species, when their seedlings are transplanted in semiarid deforested areas. Further, this study tests the possibility of using artificial shade shelters to improve the ecophysiological performance and survival of seedlings. Oak seedlings were transplanted under full sunlight conditions and beneath artificial shade shelters of two different colors： white and black. To reduce water stress, and hence isolate the effects of light treatments, a drip irrigation system was implemented at each experimental plot. Seedling survival was monitored weekly for 128 days and photosynthetic performance was assessed by measuring chlorophyll fluorescence at three opportunities during the experiment. Sun-exposed seedlings showed lower photosynthetic performance and survival rates than those beneath shelters of both colors. These results suggest that sunlight damage can reduce seedling survival when they are transplanted in exposed sites, and that shade shelters can improve the success of forest restoration programs in semiarid climates.

关键词： chlorophyll fluorescence light stress photoinhibition reforestation forest restoration

Sanger Sequencing Implementation in Clinically Ill Patients for Bacterial and Fungal Pathogens Identification

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Advances in Infectious Diseases 2022年第3期12卷 363-382页

作者： Víctor Fong-flores Andrea murillo-Gallo Luis Contreras-Ojeda Aarón Barraza Departamento de medicina Interna Benemérito Hospital General Juan María de Salvatierra La Paz México Laboratorio Biotechnologika A2 La Paz México CONACyT-CIBNOR Instituto Politécnico Nacional 195 La Paz México

The diagnosis of bacterial or fungal infections requires the identification of the pathogen etiology in the shortest time possible. Although some biomarkers are used as indicators of bacterial infections, their specificity and sensitivity are highly variable, and there is no direct relationship between the level increase of these biomarkers for mycosis. It is common to obtain negative microbiological cultures in patients infected by non-culturable, intracellular bacteria or mycosis, even though there is a high clinical suspicion of infection. This study identifies the pathogen present in critically infected patients through 16S and 18S/eEF1 genes detection by polymerase chain reaction (PCR) coupled with Sanger sequencing. Thirty clinical samples were evaluated by PCR, of which 40% were positive for fungi, 23.33% for bacteria, 26.7% for fungi and bacteria, and 10% for no pathogen. The PCRs outcomes period for bacteria or fungi was one day compared to seven and up to 14 days (on average) of microbiological culture for bacteria and fungi. Then, we assessed the relationship with the most used biomarkers (procalcitonin, C-reactive protein, globular sedimentation velocity, and the neutrophil-lymphocyte index). This combination of molecular techniques has been shown as helpful in identifying intracellular bacteria and fungi that are difficult to culture by conventional methods. Screening with genomic markers 16S and 18S/eEF1 by PCR allowed us to optimize the time to obtain the result of the infection caused by bacteria or fungi. Also, identifying the specific etiological microorganism by Sanger sequencing was very helpful in avoiding the progression of the disease and setting targeted treatment with better clinical outcomes.

关键词： Pathogen Identification Bacteria Fungi PCR Sanger Sequencing

Performance and calibration of quark/gluon-jet taggers using 140 fb^(-1) of pp collisions at √s=13 TeV with the ATLAS detector

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Chinese Physics C 2024年第2期48卷 1-25页

作者： G. Aad B. Abbott K. Abeling N.J. Abicht S.H. Abidi A. Aboulhorma H. Abramowicz H. Abreu Y. Abulaiti B.S. Acharya C. Adam Bourdarios L. Adamczyk S.V. Addepalli m.J. Addison J. Adelman A. Adiguzel T. Adye A.A. Affolder Y. Afik m.N. Agaras J. Agarwala A. Aggarwal C. Agheorghiesei A. Ahmad F. Ahmadov W.S. Ahmed S. Ahuja X. Ai G. Aielli A. Aikot m. Ait Tamlihat B. Aitbenchikh I. Aizenberg m. Akbiyik T.P.A. Åkesson A.V. Akimov D. Akiyama N.N. Akolkar K. Al Khoury G.L. Alberghi J. Albert P. Albicocco G.L. Albouy S. Alderweireldt m. Aleksa I.N. Aleksandrov C. Alexa T. Alexopoulos F. Alfonsi m. Algren m. Alhroob B. Ali H.m.J. Ali S. Ali S.W. Alibocus m. Aliev G. Alimonti W. Alkakhi C. Allaire B.m.m. Allbrooke J.F. Allen C.A. Allendes flores P.P. Allport A. Aloisio F. Alonso C. Alpigiani m. Alvarez Estevez A. Alvarez Fernandez m. Alves Cardoso m.G. Alviggi m. Aly Y. Amaral Coutinho A. Ambler C. Amelung m. Amerl C.G. Ames D. Amidei S.P. Amor Dos Santos K.R. Amos V. Ananiev C. Anastopoulos T. Andeen J.K. Anders S.Y. Andrean A. Andreazza S. Angelidakis A. Angerami A.V. Anisenkov A. Annovi C. Antel m.T. Anthony E. Antipov m. Antonelli F. Anulli m. Aoki T. Aoki J.A. Aparisi Pozo m.A. Aparo L. Aperio Bella C. Appelt A. Apyan N. Aranzabal S.J. Arbiol Val C. Arcangeletti A.T.H. Arce E. Arena J-F. Arguin S. Argyropoulos J.-H. Arling O. Arnaez H. Arnold G. Artoni H. Asada K. Asai S. Asai N.A. Asbah J. Assahsah K. Assamagan R. Astalos S. Atashi R.J. Atkin m. Atkinson H. Atmani P.A. Atmasiddha K. Augsten S. Auricchio A.D. Auriol V.A. Austrup G. Avolio K. Axiotis G. Azuelos D. Babal H. Bachacou K. Bachas A. Bachiu F. Backman A. Badea P. Bagnaia m. Bahmani A.J. Bailey V.R. Bailey J.T. Baines L. Baines O.K. Baker E. Bakos D. Bakshi Gupta V. Balakrishnan R. Balasubramanian E.m. Baldin P. Balek E. Ballabene F. Balli L.m. Baltes W.K. Balunas J. Balz E. Banas m. Bandieramonte A. Bandyopadhyay S. Bansal L. Barak m. Barakat E.L. Barberio D. Barberis m. Barbero m.Z. Barel K.N. Barends T. Barillari m-S. Barisits T. Barklow P. Baron D.A. Baron mo The ATLAS Collaboration

The identification of jets originating from quarks and gluons,often referred to as quark/gluon tagging,plays an important role in various analyses performed at the Large Hadron Collider,as Standard model measurements and searches for new particles decaying to quarks often rely on suppressing a large gluon-induced *** paper describes the measurement of the efficiencies of quark/gluon taggers developed within the ATLAS Collaboration,using √s=13 TeV proton–proton collision data with an integrated luminosity of 140 fb^(-1) collected by the ATLAS *** taggers with high performances in rejecting jets from gluon over jets from quarks are studied:one tagger is based on requirements on the number of inner-detector tracks associated with the jet,and the other combines several jet substructure observables using a boosted decision tree.A method is established to determine the quark/gluon fraction in data,by using quark/gluon-enriched subsamples defined by the jet *** in tagging efficiency between data and simulation are provided for jets with transverse momentum between 500 GeV and 2 TeV and for multiple tagger working points.

关键词： ATLAS JET QUARK GLUON TAGGING

Did maize domestication and early spread mediate the population genetics of corn leafhopper?

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Insect Science 2019年第3期26卷 569-586页

作者： Julio S. Bernal Amanda m. Davila-flores Raul F. medina Yolanda H. Chen Kyle E. Harrison Kimberly A. Berrier Department of Entomology Texas A&M University College Station Texas USA Department of Plant and Soil Sciences University of Vermont Burlington Vermont USA

Investigating how crop domestication and early farming mediated crop attributes, distributions, and interactions with antagonists may shed light on today's agricultural pest problems. Crop domestication generally involved artificial selection for traits desirable to early farmers, for example, in creased productivity or yield, and enhanced qualities, though invariably it altered the interactions between crops and insects, and expanded the geographical ranges of crops. Thus, some studies suggest that with crop domestication and spread, insect populations on wild crop ancestors gave rise to pestiferous insect populations on crops. Here, we addressed whether the emergence of corn leafhopper (Dalbulus ma id is) as an agricultural pest may be associated with domestication and early spread of maize (Zea mays mays). We used AFLP markers and mitochondrial COI sequences to assess population genetic structuring and haplotype relationships among corn leafhopper samples from maize and its wild relative Zea diploperennis from multiple locations in mexico and Argentina. We uncovered seven corn leafhopper haplotypes contained within two haplogroups, one haplogroup containing haplotypes associated with maize and the other containing haplotypes associated with Z. diploperennis in a mountainous habitat. Within the first haplogroup, one haplotype was predominant across mexican locations, and another across Argentinean locations;both were considered pestiferous. We suggested that the divergence times of the maize-associated haplogroup and of the "pestiferous" haplotypes are correlated with the chronology of maize spread following its domestication. Overall, our results support a hypothesis positing that maize domestication favored corn leafhopper genotypes preadapted for exploiting maize so that they became pestiferous, and that with the geographical expansi on of maize farming, corn leafhopper colonized Z. diploperennis, a host exclusive to secluded habitats that serves as a refuge fo

关键词： Dalbulus maidis haplotype network analysis perennial teosinte population genetic structuring Zea diploperennis Zea mays mays

A Numerical Study Comparing the Effect on Residual Stresses of Two Different Types of Projectiles During Shot Peening

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Computers, materials & Continua 2016年第3期51卷 203-215页

作者： J.Solórzano-López F.A.García-Pastor Angélica flores-Luna UNAm Facultad de QuímicaCiudad de MéxicoMéxico Cinvestav Unidad Saltillo CoahuilaMéxico TecNm Instituto Tecnológico de Tláhuac IIICiudad de MéxicoMéxico

Shot peening is a widely used technique to improve fatigue life in metallic *** processing technique introduces a subsurface compressive residual stress field through a plastic deformation of the surface caused by the impact of a large number of high-speed *** are a number of parameters that affect the residual stress field depth and *** effects of the impact angle,shot speed and shot geometry are currently being *** particular,substituting spherical cast shots by cylindrical cut wire shots is an attractive option,especially in terms of *** effect of shot geometry on residual stresses,however,needs to be further *** industrial-scale experimentation is costly and cumbersome,mathematical modeling offers a convenient alternative to carry out this type of *** present work shows a comparison between the residual stresses generated by the impact of spherical and cylindrical projectiles on a steel *** threedimensional model was developed using ABAQUS finite element commercial software(Release 6.12,Dassault Systémes,France).The results show that cylindrical shots generate residual stress fields t hat a re higher in magnitude than t hose generated by a spherical ***,the residual stress field of cylindrical shots impacting the surface at an oblique angle shows an important degree of *** effect is not found when spherical shots impact the surface at the same oblique angle.

关键词： Shot Peening Finite element method Residual Stresses

Cytotoxic effect of Spirulina platensis extracts on human acute leukemia Kasumi-1 and chronic myelogenous leukemia K-562 cell lines

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Asian Pacific Journal of Tropical Biomedicine 2017年第1期7卷 14-19页

作者： Flor Yohana flores Hernandez Sanghamitra Khandual Inocencia Guadalupe Ramírez López Center for Investigation and Assistance in Technology Design for State of JaliscoC.P.45019ZapopanJaliscoMexico

Objective: To evaluate the cytotoxic effects of Spirulina platensis extracts on acute leukemia Kasumi-1 and chronic leukemia K-562 cancer cell ***: Various concentrations of Spirulina platensis extracts(0.25–50.00 mg/m L)obtained with different solvents were used to treat cell lines for 72 h. For cytotoxic effect studies, cell viability test with trypan blue solution, mTT assay and microscopic cytomorphological assessment were ***: Spirulina extract obtained with 70% ethanol showed significant cytotoxicity in K562 and Kasumi-1 cell lines. With trypan blue solution, IC_(50) values were found to be4.64 mg/m L for K-562 and 3.68 mg/m L for Kusumi-1 cell lines. Spirulina aqueous extract also showed cytotoxicity with trypan blue method, at a slightly higher dose; where IC_(50) values were 12.68 mg/m L for K-562 and 2.13 mg/m L for Kusumi-1 cell lines. The IC_(50) values were found 0.40 mg/m L for K-562 and 0.31 mg/m L for Kusumi-1 cell lines for the 70% ethanol extract according to the mTT assay. Spirulina extract obtained with water also showed cytotoxicity but the dose was a little higher where IC_(50) values were15.77 mg/m L for K-562 and 9.44 mg/m L for Kusumi-1 cell lines. The effect of cytotoxicity with ethanol extract is quite comparable with that observed for cyclophosphamide, which is a chemical used as anticancer ***: The cytotoxicity exhibited by Spirulina extract to cancer cell lines might be due to the presence of phytopigments(carotenoids, chlorophyll, phycocyanin) as well as polysaccharides that were reported previously as constituents of the extract. So crude extracts of Spirulina can be used as a source to develop anticancer drugs.

关键词： Leukemia Cytotoxicity Spirulina Carotenoids

Risk factors for liver disease among adults of mexican descent in the United States and mexico

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World Journal of Gastroenterology 2018年第37期24卷 4281-4290页

作者： Yvonne N flores Zuo-Feng Zhang Roshan Bastani mei Leng Catherine m Crespi Paula Ramírez-Palacios Heather Stevens Jorge Salmerón Unidad de Investigación Epidemiológica y en Servicios de Salud Delegación MorelosInstituto Mexicano del Seguro SocialCuernavacaMorelos 62000México UCLA Department of Health Policy and management and Kaiser Permanente Center for Health Equity Fielding School of Public HealthLos AngelesCA 90095United States UCLA Cancer Prevention and Control Research Center Fielding School of Public Health and Jonsson Comprehensive Cancer CenterLos AngelesCA 90095United States UCLA Division of General Internal medicine and Health Services Research Los AngelesCA 90095United States UCLA Department of Biostatistics Fielding School of Public HealthLos AngelesCA 90095United States University of Washington School of MedicineSeattleWA 98195United States Universidad Nacional Autónoma de méxico Academic Epidemiology Research UnitAvenida Universidad 3000Ciudad UniversitariaCoyoacánMexico City 04510México Centro de Investigación en Salud Poblacional Instituto Nacional de Salud PúblicaCuernavacaMorelos 62100México

AIm To compare the prevalence of chronic liver disease(CLD) risk factors in a representative sample of mexicanAmericans born in the United States(US) or mexico, to a sample of adults in *** Data for mexican-Americans in the US were obtained from the 1999-2014 National Health and Nutrition Examination Survey(NHANES), which includes persons of mexican origin living in the US(n = 4274). The NHANES sample was restricted to mexican-American participants who were 20 years and older, born in the US or mexico, not pregnant or breastfeeding, and with medical *** data in mexico were obtained from the 2004-2013 Health Worker Cohort Study in Cuernavaca, mexico(n =9485). The following known risk factors for liver disease/cancer were evaluated: elevated aminotransferase levels(elevated alanine aminotransferase was defined as > 40 IU/L for males and females; elevated aspartate aminotransferase was defined as > 40 IU/L for males and females), infection with hepatitis B or hepatitis C,metabolic syndrome, high total cholesterol, diabetes,obesity, abdominal obesity, and heavy alcohol use. The main independent variables for this study classified individuals by country of residence(i.e., mexico vs the US) and place of birth(i.e., US-born vs mexico-born).Regression analyses were used to investigate CLD risk *** After adjusting for socio-demographic characteristics,mexican-American males were more likely to be obese,diabetic, heavy/binge drinkers or have abdominal obesity than males in mexico. The adjusted multivariate results for females also indicate that mexican-American females were significantly more likely to be obese, diabetic, be heavy/binge drinkers or have abdominal obesity than mexican females. The prevalence ratios and prevalence differences mirror the multivariate analysis findings for the aforementioned risk factors, showing a greater risk among US-born as compared to mexico-born mexicanAmericans. CONCLUSION In this study, mexican-Americans i

关键词： Liver disease Risk factors Health disparities mexico mexican Americans Latinos

mechanical and natural ventilation systems in a greenhouse designed using computational fluid dynamics

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International Journal of Agricultural and Biological Engineering 2014年第1期7卷 1-16页

作者： Jorge flores-Velazquez Juan I.montero Esteban J.Baeza Juan C.Lopez mexican Institute of Water Technology.Paseo Cuauhnáhuac 8532 Col.ProgresoC.P.62550JiutepecMor.Mexico Institut de Recerca i Tecnologia Agroalimentàries 08348Cabrils(Barcelona)Spain IFAPA Centro La mojonera(Junta de Andalucía) Camino San Nicolás 104745 La MojoneraAlmeríaSpain Fundación Cajamar.Estación Experimental“Las Palmerillas”Autovía del mediterráneo Km 416 704710El EjidoAlmeríaSpain

The aim of this study was to analyse air exchange and temperature distribution in a greenhouse with combined mechanical and natural ventilation and to design more efficient mechanical ventilation *** this purpose,a computational fluid dynamics(CFD)model of the greenhouse was *** configurations were considered:Configuration 1(mechanical ventilation and closed roof ventilators),Configurations 2 and 3(mechanical ventilation and roof ventilators open 30%and 100%,respectively).After validation,the CFD model was used to improve the design of the greenhouse mechanical ventilation system in each of the three configurations *** greenhouse lengths,28 m,50 m,75 m and 100 m,were used in the *** to fan ventilation only,roof ventilation improved the climate of fan-ventilated greenhouses in terms of the air exchange rate(22%)and climate uniformity because the internal air was mixed better than with mechanical ventilation *** the greenhouse length increased,more advantages were achieved with natural ventilation compared to mechanical *** most configurations,there was a strong linear correlation between temperature gradient and greenhouse *** greenhouse whose regression line had the steepest slope was the one with closed roof *** the fan capacity produced a general reduction in temperature,but the effect was less intense for the greenhouses with open roof *** to box inlet ventilators,an enlarged continuous inlet in the wall opposite the fans increased overall system performance because it eliminated backflow recirculation zones,which are prone to produce high temperatures.

关键词： greenhouse cooling fan ventilation roof ventilators combined ventilation

Neutron star cooling and GW170817 constraint within quark-meson coupling models

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Chinese Physics C 2021年第2期45卷 531-547页

作者： Odilon Lourenço César H.Lenzi mariana Dutra Tobias Frederico m.Bhuyan Rodrigo Negreiros César V.flores Guilherme Grams Débora P.menezes Departamento de Física Instituto Tecnológico de AeronáuticaDCTA12228-900São Josédos CamposSPBrazil Department of Physics Faculty of ScienceUniversity of MalayaKuala Lumpur 50603Malaysia Atomic molecular and Optical Research Group Advanced Institute of Materials ScienceTon Duc Thang UniversityHo Chi Minh CityVietnam Faculty of Applied Sciences Ton Duc Thang UniversityHo Chi Minh CityVietnam Instituto de Física Universidade Federal Fluminense 20420NiteróiRJBrazil Centro de Ciências Exatas Naturais e TecnológicasUEMASULRua Godofredo Viana 1300Centro CEP:65901-480ImperatrizMaranhãoBrazil Departamento de Física Universidade Federal de Santa CatarinaFlorianópolisSCCP 476CEP 88.040-900Brazil Univ.Lyon Univ.Claude Bernard Lyon 1CNRS/IN2P3IP2I LyonUMR 5822F-69622VilleurbanneFrance

In the present work,we used five different versions of the quark-meson coupling(QmC)model to compute astrophysical quantities related to the GW170817 event and the neutron star cooling *** of the models are based on the original bag potential structure and three versions consider a harmonic oscillator potential to confine *** bag-like models also incorporate the pasta phase used to describe the inner crust of neutron *** a simple method studied in the present work,we show that the pasta phase does not play a significant ***,the QmC model that satisfies the GW170817 constraints with the lowest slope of the symmetry energy exhibits a cooling profile compatible with observational data.

关键词： equation of state compact star cooling in stars quark-meson coupling models tidal deformability neutron star merger