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journal of Energy Chemistry 2017年第5期26卷 942-947页

作者： Alejandra Cruz-Hernández j.arturo mendoza-nieto Heriberto Pfeiffer Laboratorio de Fisicoquímica y Reactividad de Superficies(LaFReS) Instituto de Investigaciones en MaterialesUniversidad Nacional Autónoma de MéxicoCircuito exterior s/nCiudad UniversitariaDel.CoyoacánCP 04510Ciudad de MéxicoMexico

In this work, CaO-NiO mixed oxide powders were evaluated as consecutive CO;chemisorbents and catalytic materials for hydrogen production thought the CH;reforming process. Between the NiO impregnated CaO and CaO-NiO mechanical composite, the first one presented better chemical behaviors during the CO;capture and CH;reforming processes, obtaining syngas（H;+ CO） as final product. Results showed that syngas was produced at two different temperature ranges, between 400 and 600 °C and at T > 800 °C, where the first temperature range corresponds to the CH;reforming process but the second temperature range was attributed to a different catalytic reaction process: CH;partial oxidation. These results were confirmed through different isothermal and cyclic experiments as well as by XRD analysis of the final catalytic products, where the nickel reduction was evidenced. Moreover, when a CO-O;flow was used during the carbonation process a triple process was achieved:（i） CO oxidation,（ii） CO;chemisorption and（iii） CH;reforming. Using this gas flow the hydrogen production was always higher than that obtained with CO;.

关键词： Methane reforming CO2 capture Calcium oxide H2 production NiO supported

Patch isolation and shape predict plant functional diversity in a naturally fragmented forest

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journal of Plant Ecology 2018年第1期11卷 136-146页

作者： Amaranta Arellano-Rivas j.arturo De-Nova Miguel A.Munguía-Rosas Instituto de Investigación de Zonas Desérticas Universidad Autónoma de San Luís PotosíSan Luis Potosí78377México Laboratorio de Ecología Terrestre Departamento de Ecología HumanaCentro de Investigación y Estudios Avanzados del Instituto Politécnico Nacional(CINVESTAV)Mérida 97310México Facultad de Agronomía Universidad Autónoma de San Luís PotosíSan Luis Potosí78321México

Aims It is known that taxonomic diversity can be predicted by the spatial configuration of the habitat,in particular by its area and degree of ***,taxonomic diversity is a poor predictor of ecosystem *** functional diversity is strongly linked to the func-tionality and stability of ecosystems,little is known about how changes in the spatial configuration of the habitat affect functional *** this study,we evaluated whether the spatial configuration of forest patches predicts the functional diversity of plants in a fragmented *** Five functional leaf traits(leaf dry matter content,leaf punch force,specific leaf area,leaf size and leaf thickness)were measured for 23 dominant plant species in 20 forest patches in a naturally fragmented forest on the yucatan ***-weighted multivariate and individual trait metrics of functional diversity were calculated and cor-related with size,degree of isolation and the shape of forest *** Findings Patch shape was negatively correlated with multivariate and individ-ual trait(leaf dry matter content and leaf size)metrics of functional *** isolation measures were also negatively correlated with individual trait(leaf dry matter content,leaf punch force and leaf size)metrics of functional *** other words,greater patch shape irregularity and isolation degree impoverish plant func-tional *** is the first report of the negative effects of patch shape irregularity and isolation on the functional diversity of plant communities in a forest that has been fragmented for a long time.

关键词： forest fragmentation functional diversity habitat spatial configuration petenes yucatan

影响端粒结构和动力学的微演化过程:端粒在癌症中的作用

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癌症 2008年第7期27卷 775-783页

作者： j.arturo Londoo-Vallejo UMR7147 Institut Curie-UPMC-CNRS 26rue d'Ulm75248 ParisFrance

端粒在基因组稳定、细胞核结构以及减数分裂中染色体配对中发挥关键作用。细胞每分裂一次,端粒会缩短,缩短的端粒可能再延长或不延长,这取决于细胞内是否存在一种专用酶-端粒酶。由于人体的多数体细胞并不表达端粒酶,因此发育和衰老过... 详细信息

端粒在基因组稳定、细胞核结构以及减数分裂中染色体配对中发挥关键作用。细胞每分裂一次,端粒会缩短,缩短的端粒可能再延长或不延长,这取决于细胞内是否存在一种专用酶-端粒酶。由于人体的多数体细胞并不表达端粒酶,因此发育和衰老过程中端粒必然缩短。在生理条件下,端粒缩短与延长的细胞增殖相矛盾,因此端粒长度决定了细胞的增殖潜能,并作为细胞无限生长的预防机制。相反,在细胞增殖检查点受破坏的细胞中,缩短的端粒可导致染色体融合并启动断裂-融合-桥周期,这极大地促发了基因组不稳定。在体外研究中,转化细胞中由于端粒严重缩短造成的基因组高度不稳定,在这种细胞种蓄积了有害的遗传改变,从而导致细胞最终死亡(危象)。同时,随机的遗传或拟遗传学改变可使细胞获得端粒维持机制(以及其它肿瘤表型),从而成为永生细胞。在体内研究中,尽管在早期肿瘤细胞中发现端粒缩短和其它形式的端粒功能障碍可能使基因组不稳定,但端粒功能障碍对于人类肿瘤表型的直接作用有待进一步研究。

关键词：端粒缩短端粒酶危象基因组不稳定永生化肿瘤发生核型演化断裂-融合-桥突变基因表型染色体不稳定表型微卫星不稳定

Tri-axial accelerometry shows differences in energy expenditure and parental effort throughout the breeding season in long-lived raptors

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Current Zoology 2022年第1期68卷 57-67页

作者： Pascual LOPEZ-LOPEZ arturo MPERONA Olga EGEA-CASAS jon MORANT Vicente URIOS Movement Ecology Laboratory Cavanilles Institute of Biodiversity and Evolutionary BiologyUniversity of Valencia.C/Catedratico JoseBeltran 2E-46980 PaternaValenciaSpain Department of Ornithology Aranzadi Sciences SocietyDonostia-S.SebastianGuipuzcoa 03690Spain Vertebrates Zoology Research Group University of AlicanteApdo.99Alicante E-03080Spain

Cutting-edge technologies are extremely useful to develop new workflows in studying ecological data,particularly to understand animal behavior and movement trajectories at the individual *** parental care is a well-studied phenomenon,most studies have been focused on direct observational or video recording data,as well as experimental ***,what happens out of our sight still remains *** high-frequency GPS/GSM dataloggers and tri-axial accelerometers we monitored 25 Bonelli’s eagles Aquila fasciata during the breeding season to understand parental activities from a broader *** used recursive data,measured as number of visits and residence time,to reveal nest attendance patterns of biparental care with role specialization between *** data interpreted as the overall dynamic body acceleration,a proxy of energy expenditure,showed strong differences in parental effort throughout the breeding season and between ***,males increased substantially their energetic requirements,due to the increased workload,while females spent most of the time on the ***,during critical phases of the breeding season,a low percentage of suitable hunting spots in eagles’territories led them to increase their ranging behavior in order to find food,with important consequences in energy consumption and mortality *** results highlight the crucial role of males in raptor species exhibiting biparental ***,we exemplify how biologging technologies are an adequate and objective method to study parental care in raptors as well as to get deeper insight into breeding ecology of birds in general.

关键词： biologging GPS movement ecology ODBA space use telemetry

Hydrogen production through glycerol steam reforming using Co catalysts supported on SBA-15 doped with Zr,Ce and La

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journal of Energy Chemistry 2017年第1期26卷 42-48页

作者： Alicia Carrero arturo j.Vizcaíno joséA.Calles Lourdes García-Moreno Department of Chemical and Energy Technology ESCETRey Juan Carlos University28933 MóstolesSpain

The steam reforming of glycerol has been studied at 500 and 600 oC using Co/SBA-15 and Co/M/SBA-15（M: Zr, Ce, or La） promoted catalysts. The prepared materials were characterized by inductively coupled plasma atomic emission spectroscopy（ICP-AES）, X-ray powder diffraction（XRD）, hydrogen temperatureprogramed reduction（H;-TPR）, ammonia temperature-programed desorption（NH;-TPD）, nitrogen physisorption analysis（N;-BET）, transmission electron microscopy（TEM） and thermogravimetric analysis（TGA）. The incorporation of promoters like Zr, Ce and La on SBA-15 support and successive Co impregnation leaded to smaller cobalt crystallites improving metaldispersion. Besides, stronger metal-support interactions between Co species and M/SBA-15 supports were observed. Thanks to the incorporation of Zr, La and mainly Ce, promoted catalysts present higher glycerol conversion than Co/SBA-15 along 5 h of time on stream. Besides, at 600 oC, Co/M/SBA-15（M: Zr, Ce, or La） catalysts produce higher hydrogen amounts than Co/SBA-15.

关键词： Cobalt SBA-15 Cerium Zirconium Lanthanum Steam reforming Hydrogen

Guidelines for rational design of high-performance absorbents:A case study of zeolite adsorbents for emerging pollutants in water

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Green Energy & Environment 2017年第4期2卷 363-369页

作者： Xiaoxuan Wei Ya Wang arturo j.Hernndez-Maldonado Zhongfang Chen Department of Chemistry Institute for Functional Nanomaterials University of Puerto Rico Rio Piedras Campus Department of Chemical Engineering Institute for Functional Nanomaterials University of Puerto Rico Mayagüez Campus

Rational design is important to achieve high-performance sorbents used to remove the contaminants of emerging concern(CECs) from ***, it is hard to propose effective design guidelines due to the lack of a clear understanding of the interaction mechanisms. By means of systematic quantum chemical computations, as a case study, we investigated the interactions between zeolite X/M^(n+)-zeolite X(Si/Al=1,M^(n+)=Cu^(2+) and Ni^(2+)) and three commonly used CECs(namely salicylic acid, carbamazepine and ciprofloxacin) in water to clarify the adsorption mechanisms. Our computations found that anionic salicylic acid cannot be adsorbed by neither zeolite X nor M^(n+)-zeolite X in neutral water due to the high electrostatic repulsion. In comparison, carbamazepine and ciprofloxacin have favorable binding energies with both zeolite X and M^(n+)-zeolite X, and their interactions with M^(n+)-zeolite X are stronger due to the joint effects of H-bond, metal complexation and electrostatic interaction. The adsorption loading of ciprofloxacin, which has a large molecular size, on M^(n+)-zeolite X is limited due to the steric hindrance. In general, steric hindrance, electrostatic interaction, H-bond and metal complexation are dominant factors for the examined systems in this study. Thus, for the design of high-performance absorbing materials, we should fully consider the molecular properties of pollutants(molecular size, surface electrostatic potential and atomic type, etc.), and properly enhance the favorable effects and avoid the unfavorable factors as much as possible under the guidance of the interaction mechanisms.

关键词： Adsorption mechanism Adsorbent design guidelines Quantum chemical computations Contaminants of emerging concern Zeolite X

Lepidium meyenii (Maca) improved semen parameters in adult men

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Asian journal of Andrology 2001年第4期3卷 301-303页

作者： Gustavo F.Gonzales Amanda Cordova Carla Gonzales arturo Chung Karla Vega arturo Villena Department of Physiological Sciences Faculty of Science and Philosopy and Instituto de Investigacions de la Altura. University Peruana Cayetano Heredia Lima PeruDepartment of Physiological Sciences Faculty of Science and Philosopy and Instituto de Investigacions de la Altura. University Peruana Cayetano Heredia Lima PeruDepartment of Physiological Sciences Faculty of Science and Philosopy and Instituto de Investigacions de la Altura. University Peruana Cayetano Heredia Lima PeruDepartment of Physiological Sciences Faculty of Science and Philosopy and Instituto de Investigacions de la Altura. University Peruana Cayetano Heredia Lima PeruDepartment of Physiological Sciences Faculty of Science and Philosopy and Instituto de Investigacions de la Altura. University Peruana Cayetano Heredia Lima PeruDepartment of Physiological Sciences Faculty of Science and Philosopy and Instituto de Investigacions de la Altura. University Peruana Cayetano Heredia Lima Peru

Aim: The present study was designed to determine the effect of a 4-month oral treatment with tablets of Lepidiwnmeyenii (Maca) on seminal analysis in nine adult normal men aged 24-44 years old. Methods: Nine men receivedtablets of Maca (1500 or 3000 mg/day) for 4 months. Seminal analysis was performed according to guidelines of theWorld Health Organization (WHO). Serum luteinizing hormone (LH), follicle stimulating hormone (FSH), prolactin(PRL), testosterone (T) and estradiol (E_2) were measured before and after treatment. Results; Treatment withMaca resulted in increased seminal volume, sperm count per ejaculum, motile sperm count, and sperm motility. Serumhormone levels were not modified with Maca treatment. Increase of sperm count was not related to dose of ***: Maca improved sperm production and sperm motility by mechanisms not related to LH, FSH, PRL, Tand E_2. (Asian j Androl 2001 Dec; 3: 301 - 303)

关键词： sperm count sperm motility Peruvian plants Maca Lepidium meyenii

FedIDS:a federated cloud storage architecture and satellite image delivery service for building dependable geospatial platforms

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International journal of Digital Earth 2018年第7期11卷 730-751页

作者： j.L.Gonzalez-Compean Victor j.Sosa-Sosa arturo Diaz-Perez jesus Carretero Ricardo Marcelin-jimenez Cinvestav-Tamulipas Ciudad VictoriaMexico ARCOS Research Group University Carlos IIIMadridSpain UAM Iztapalapa CDMX and associated to InfotecMexico

Earth observation satellites produce large amounts of images/data that not only must be processed and preserved in reliable geospatial platforms but also efficiently disseminated among partners/researchers for creating derivative products through collaborative *** can face up this challenge in a cost-effective manner by using cloud ***,outages and violations of integrity/confidentiality associated to this technology could *** article presents FedIDS,a suite of cloud-based components for building dependable geospatial *** Fed component enables organizations to build shared geospatial data infrastructure through federation of independent cloud resources to withstand outages,whereas IDS avoids violations of integrity/confidentiality of images/data in sharing information and collaboration workflows.A FedIDS prototype,deployed in Spain and Mexico,was evaluated through a study case based on a satellite imagery captured by a Mexican antenna and another based on a satellite imagery of a European observation *** acquisition,storage and sharing of images among users of the federation,the exchange of images between Mexican and Spanish sites and outage scenarios were *** evaluation revealed the feasibility,reliability and efficiency of FedIDS,in comparison with available solutions,in terms of performance,storage consume and integrity/confidentiality when sharing images/data in collaborative scenarios.

关键词： Satellite imagery Earth observation archives spatial data infrastructure collaborative workflows security reliability

Zeolite-templated carbons as effective sorbents to remove methylsiloxanes and derivatives:A computational screening

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Green Energy & Environment 2021年第6期6卷 884-892页

作者： Shiru Lin Kaitlyn A.jacoby jinxing Gu Dariana R.Vega-Santander arturo j.Hernaandez-Maldonado Zhongfang Chen Department of Chemistry University of Puerto RicoRío PiedrasSan JuanPR 00931USA Department of Chemistry&Biochemistry Elizabethtown CollegeElizabethtownPA 17022USA Department of Chemical Engineering University of Puerto RicoMayaguez CampusMayaguezPR 00681USA

Though widely used in our daily lives,volatile methylsiloxanes and derivatives are emerging contaminants and becoming a high-priority environment and public health *** effective sorbent materials can remove siloxanes in a cost-effective ***,by means of Grand Canonical Monte Carlo(GCMC)simulations,we evaluated the potentials of the recently proposed 68 stable zeolite-templated carbons(ZTCs)(PNAS 2018,115,E8116-E8124)for the removal of four linear methylsiloxanes and derivatives as well as two cyclic methylsiloxanes by the calculated average loading and average adsorption energy *** ZTCs,namely ISV,FAU1,FAU3,and H8326836,were identified with the top 50%adsorption performance toward all the six targeted contaminants,which outperform activated *** first principles computations revealed that steric hindrance,electrostatic interactions(further enhanced by charge transfer),and CH-p interactions account for the outstanding adsorption performance of these *** work provides a quick procedure to computationally screen promising ZTCs for siloxane removal,and help guide future experimental and theoretical investigations.

关键词： Zeolite-templated carbons Contaminants of emerging concern Methylsiloxanes GCMC simulations Density functional theory calculations

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：空间统计墨西哥干旱时间土壤水分蒸发蒸腾损失总量可变性加利福尼亚森林火