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Alternative approaches for estimating missing climate data:application to monthly precipitation records in South- Central Chile

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Forest Ecosystems 2018年第4期5卷 390-399页

作者： Alonso Barrios Guillermo Trincado Rene Garreaud Escuela de Graduados Facultad de Ctencias Forestales y Recursos Naturales Universidad Austral de ChileBox 567ValdiviaChile departamento de Ciencias Forestales Facuitad de Ingenieria ForestalUnlversidad del Tolima Box 6299 Ibague Colombia instituto de Bosques y Sociedad Facultad de Ciencias Forestales y Recursos NaturalesUniversidad Austraide ChileBox 567 ValdiviaChile departamento de Geofistca Facultad de Ciencias Fisicas y MatematicasUniversidad de ChileSantiagoChile

Background: Over the last decades interest has grown on how climate change impacts forest resources. However,one of the main constraints is that meteorological stations are riddled with missing climatic data. This study compared five approaches for estimating monthly precipitation records: inverse distance weighting(IDW), a modification of IDW that includes elevation differences between target and neighboring stations(IDW_m), correlation coefficient weighting(CCW), multiple linear regression(MLR) and artificial neural networks(ANN).Methods: A complete series of monthly precipitation records(1995-2012) from twenty meteorological stations located in central Chile were used. Two target stations were selected and their neighboring stations, located within a radius of25 km(3 stations) and 50 km(9 stations), were identified. Cross-validation was used for evaluating the accuracy of the estimation approaches. The performance and predictive capability of the approaches were evaluated using the ratio of the root mean square error to the standard deviation of measured data(RSR), the percent bias(PBIAS), and the NashSutcliffe efficiency(NSE). For testing the main and interactive effects of the radius of influence and estimation approaches,a two-level factorial design considering the target station as the blocking factor was ***: ANN and MLR showed the best statistics for all the stations and radius of influence. However, these approaches were not significantly different with IDW_m. Inclusion of elevation differences into IDW significantly improved IDW_m estimates. In terms of precision, similar estimates were obtained when applying ANN, MLR or IDW_m, and the radius of influence had a significant influence on their estimates, we conclude that estimates based on nine neighboring stations located within a radius of 50 km are needed for completing missing monthly precipitation data in regions with complex ***: It is concluded that approaches based on ANN

关键词： Climatological data Cross-validation Artificial neural networks Multiple linear regression

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One DOF mechanism for the mechanical harvest of vines in an arbor structure and the validation of the acceleration of grape berry harvesting

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Frontiers of Mechanical Engineering 2015年第3期10卷 221-232页

作者： Pedro BOCCA facultad de ingenieria Universidad Nacional de San Juan San Juan5400 Argentina

In the mechanized harvest of vines, grape berries are detached through the vibration to the structure supporting the clusters. According to the kind of guide selected, the clusters require one or two vibration directions in the structure. For guiding in parral structures, vibration is necessary in two directions or planes： One perpendicular to the other. The guide branches producing the clusters develop in these planes, and the guiding is called H-guiding. Mechanism theory indicates that a mechanism has as many degrees of freedom as its actuators, and an actuator is needed to achieve a certain vibration. Having the smallest number of possible actuators is beneficial in reducing moving parts and achieving more compact and easily controllable mecha- nisms. In this case, a single degree-of-freedom mechanism is proposed. It is capable of generating vibrations on two planes： One perpendicular to the other. This mechanism is the sum of two link mechanisms on perpendicular planes with a common outlet located at the output rod of the mechanism where the actuator is found. As the distance between the soil and the elements containing the clusters is not constant, a system has been designed to measure the accelerations at the bars and the rocker to validate the acceleration values that detach the grape berries in a prototype in a lab experiment, to ensure that the acceleration needed for pulling the grape berries are produced at any contact point of the bar.

关键词： harvest mechanisms one DOF vibration

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Effects of chlorpyrifos on enzymatic systems of Cydia pomonella （Lepidoptera： Tortricidae） adults

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Insect Science 2017年第3期24卷 455-466页

作者： Laura Beatriz Parra Morales Raul Adolfo Alzogaray Liliana Cichon Silvina Garrido Jimena Soleno Cristina Monica Montagna Laboratorio de Investigaciones Bioquimicas Quimicas y de Medio Ambiente Facultad de Ingenieria Universidad Nacional del ComahueBuenos Aires 1400 (Q83001BX) Neuquen facultad de Ciencias del Ambiente y la Salud Universidad Nacional del Comahue Buenos Aires 1400 Neuquen Centro de Investigaciones de Plagas e Insecticidas (CIPEIN-UNIdeFICONICET) Villa Martelli Buenos Aires instituto de Investigacion e ingenieria Ambiental (3iA-UNSAM) San Martin Provincia de Buenos Aires instituto Nacional de Tecnologia Agropecuaria Estacion Experimental Alto Valle General Roca Argentina

The control program of codling moth （Cydia pomonella L.） in the Rio Negro and Neuqu6n Valley is intended to neonate larvae. However, adults may be subjected to sublethal pesticide concentrations generating stress which might enhance both mutation rates and activity of the detoxification system. This study assessed the exposure effects of chlorpyrifos on target enzyme and, both detoxifying and antioxidant systems of surviving adults from both a laboratory susceptible strain （LSS） and a field population （FP）. The results showed that the FP was as susceptible to chlorpyrifos as the LSS and, both exhibited a similar chlorpyrifos-inhibitory concentration 50 （IC50） of acetylcholinesterase （ACHE）. The FP displayed higher carboxylesterase （CarE） and 7-ethoxycoumarine O-deethylase （ECOD） activities than LSS. Both LSS and FP showed an increase on CarE activity after the exposure to low-chlorpyrifos concentrations, followed by enzyme inhibition at higher concentrations. There were no significant differences neither in the activities of glutathione S-transferases （GST）, catalase （CAT） and superoxide dismutase （SOD） nor in the reduced glutathione （GSH） content between LSS and FP. Moreover, these enzymes were unaffected by chlorpyrifos. In conclusion, control adults from the FP exhibited higher CarE and ECOD activities than control adults from the LSS. AChE and CarE activities were the most affected by chlorpyrifos. Control strategies used for C. pomonella, such as rotations of insecticides with different modes of action, will probably delay the evolution of insecticide resistance in FPs from the study area.

关键词： acetylcholinesterase antioxidant system chlorpyrifos codling moth detoxification enzymes

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Mercury levels in human population from a mining district in Western Colombia

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Journal of Environmental Sciences 2018年第6期30卷 83-90页

作者： Harry Gutiérrez-Mosquera S.B.Sujitha M.P.Jonathan S.K.Sarkar Fairy Medina-Mosquera Helcias Ayala-Mosquera Gladis Morales-Mira Laura Arreola-Mendoza facultad de ingenieria Universidad Tecnologica del Choco Carrera 22 No.18B-10 Quibdo Colombia Centro Interdisciplinario de Investigaciones y Estudios sobre Medio Ambiente y desarrollo (CIIEMAD) Instituto Politecnico Nacional (IPN) Calle 30 de junio de 1520 Barrio la Laguna Ticomdn Del. Gustavo A. Madero C.P.07340 Ciudad de Mexico Mexico department of Marine Science University of Calcutta 35 Ballygunge Circular Road Calcutta 700 019 India instituto de Investigaciones Ambientales del Pacifico (IIAP) Carrera 6 No. 37-39 quibdo Colombia facultad de ingenieria Uniuersidad de Medellin Carrera 87 No. 30-65 Medellin Colombia

A biomonitoring study was carried out to examine the adverse impacts of total mercury in the blood（HgB）, urine（Hg U） and human scalp hair（HgH） on the residents of a mining district in Colombia. Representative biological samples（scalp hair, urine and blood） were collected from volunteered participants（n = 63） to estimate the exposure levels of THg using a Direct mercury analyzer. The geometric mean of THg concentrations in the hair,urine and blood of males were 15.98 μg/g, 23.89 μg/L and 11.29 μg/L respectively, whereas the females presented values of 8.55 μg/g, 5.37 μg/L and 8.80 μg/L. Chronic urinary Hg（HgU）levels observed in male workers（32.53 μg/L） are attributed to their long termed exposures to inorganic and metallic mercury from gold panning activities. On an average, the levels of THg are increasing from blood（10.05 μg/L） to hair（12.27 μg/g） to urine（14.63 μg/L）.Significant positive correlation was found between hair and blood urinary levels in both male and female individuals. Thus the present biomonitoring investigation to evaluate the Hg levels and associated health issues would positively form a framework for further developmental plans and policies in building an ecofriendly ecosystem.

关键词： Humans Mercury Gold panning Biomarkers Toxicity Colombia

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Dynamics of populations with two sexes

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International Journal of Biomathematics 2015年第4期8卷 127-144页

作者： M. Cecilia Perez E. Adriana Saavedra Mariano A. Ferrari facultad de ingenieria Universidad Nacional de la Patagonia San Juan Bosco Esquel Chubut Argentina facultad de ingenieria Universidad Nacional de la Patagonia San Juan Bosco Trelew Chubut Argentina facultad de Ingenierla Universidad Nacional de la Patagonia San Juan Bosco Puerto Madryn Chubut Argentina Centro Nacional Patagdnico CONICET Puerto Madryn Chubut Argentina

A mathematical model is presented in order to describe the dynamics of polygamous populations, bearing in mind single individuals of both sexes and the development of reproductive groups. In this context, the description leads us to consider positive homogeneous dynamical systems, establishing conditions for the stationary state existence and its local stability. A fourth pre-reproductive stage was considered, i.e. males and females spend part of their lives before being in condition to reproduce, as a first step to consider more general models. Finally, we parametrized the proposed model using southern elephant seal data, to analyze the direct applicability to a real population.

关键词： Dynamical systems two-sex model mating system local stability.

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Movement initiation of millimeter particles on a rotating rough surface: The role of adhesion

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Particuology 2020年第6期18卷 92-99页

作者： Karina de los Angeles Valenzuela Aracena Rodolfo O.Unac Irene Ippolito Ana M.Vidales INFAP CONICETDepartamento de FisicaFacultad de Ciencias Fisico Matematicas y NaturalesUniversidad Nacional de San LuisEjercito de los Andes 950D5700HHWSan LuisArgentina Universidad de Buenos Aires Facultad de IngenieriaGrupo de Medios PorososPaseo Colon 850C1063ACV Buenos AiresArgentina

We performed experiments to determine the critical moment for movement initiation of a millimeter bead on a rotating rough *** corresponding critical angular velocities were measured for glass and stainless-steel ball bearings over two different rough surfaces with glued glass beads.A basic theoretical analysis was developed to explain the observed *** the expectation of a simple approach with the presence of the obstacles offered by a rough surface could be sufficient to describe the problem,we prove here that the sole con sideration of these obstacles,and even friction,are insufficient to explain the results in the range of a few-millimeter glass *** the thermodynamic work of adhesion between surfaces is significant,the adhesion forces must be considered in the force balance for particle detachment:.This effect is a determinant for describing theoretically and numerically the dynamics of millimeter particles.

关键词： detachment Adhesion Centrifugation

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The first meteorological observations at a tropical high elevation site:Antisana,1846

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Journal of Mountain Science 2016年第6期13卷 1047-1055页

作者： Aria Ma M.FARRONA Fernando DOMINGUEZ-CASTRO Ma Cruz GALLEGO Jose M.VAQUERO departamento de Fisica Facultad de CienciasUniversidad de ExtremaduraBadajoz 06071Spain instituto de Fisica de Cantabria(UC-CSIC) Santander 39005Spain departamento de ingenieria Civily Ambiental Escuela Politecnica NacionalQuito 170112Ecuador instituto Nacional de Meteorologiae Hidrologia Quito 170135Ecuador instituto universitario de investigación del agua cambio climático y sostenibilidad (iacys) universidad de extremaduraBadajoz 06071，Spain departamento de física centro universitario de mérida universidad de extremaduraMerida 06800Spain

Antisana is a stratovolcano with an associated glacier located in the Ecuadorian Andes. Dr Aguirre made meteorological readings every day, at every hour from sunrise to sunset, from december 1845 to december 1846, at Antisana using a meteorological station at 4060 mamsl （meters above mean sea level）. Unfortunately, only the monthly average data have been preserved. These meteorological data are here studied and compared with the closest modern stations for monthly values of temperature, rainfall, and pressure. According to these comparisons, the year 1846 was rainy and cold in comparison with the current climate. Moreover, these observations have been useful to help resolve a debate about a possible E1Nifio event in 1846 with the high precipitation in Antisana and Quito in 1846 discarding the occurrence of an E1 Nifio event. The probable occurrence of a La Nifia event is discussed. These data are the earliest known systematic instrumental meteorological observations taken at above 4000 mamsl.

关键词： Early instrumental records Glacier Pastclimate conditions

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Symmetry in optics and photonics:a group theory approach

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Science Bulletin 2018年第4期63卷 244-251页

作者： B.M.Rodriguez-Lara Ramy EI-Ganainy Julio Guerrero Tecnologico de Monterrey.Escuela de ingenieria y Ciencias Monterrey 64849Mexico instituto Nacional de Astrofisica Optica y Electr6nicaPueblaCP 72840Mexico department of Physics and Hexes Center for Quantum Phenomena Michigan Technological UniversityHoughton.MI 49931USA departamento de Matematicas Facultad de Ciendas Experimentales y de la SaludCampus Las LagunillasUniversidad de Jaen23071JaenSpain departamento de Ingenierfa y Tecnologia de Computadores Facultad de lnformdticaCampus EspinardoUnivesidad de Murcia30100 MurciaSpain

Group theory(GT) provides a rigorous framework for studying symmetries in various disciplines in physics ranging from quantum field theories and the standard model to fluid mechanics and chaos theory. To date, the application of such a powerful tool in optical physics remains limited. Over the past few years however, several quantum-inspired symmetry principles(such as parity-time invariance and supersymmetry) have been introduced in optics and photonics for the first time. despite the intense activities in these new research directions, only few works utilized the power of group theory. Motivated by this status quo, here we present a brief overview of the application of GT in optics, deliberately choosing examples that illustrate the power of this tool in both continuous and discrete setups. We hope that this review will stimulate further research that exploits the full potential of GT for investigating various symmetry paradigms in optics, eventually leading to new photonic devices.

关键词： Group theoryHelmholtz equationDiscrete opticsParity-time (PT) symmetry

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Physical activation of graphene: An effective, simple and clean procedure for obtaining microporous graphene for high-performance Li/S batteries

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Nano Research 2019年第4期12卷 759-766页

作者： Almudena Benitez Alvaro Caballero Julian Morales Jusef Hassoun Enrique Rodriguez-Castellon Jesus Canales-Vazquez Dpto. Quimica Inorganica e ingenieria Qutmica Instituto de Quimica Fina y Nanoquimica Universidad de Cordoba 14071 Cordoba Spain departm ent of Chemical and Pharmaceutical Sciences University of Ferrara Via Fossato di Mortara 17 44121 Ferrara Italy Dpto. de Quimica Inorganica Cristalografia y Mineralogia Facultad de Ciencias Universidad de Malaga 29071 Malaga Spain instituto de Energias Renovables Universidad de Castilla-La Mancha Paseo de La Investigacion 1 Albacete 02071 Spain

Graphe ne nano sheets are a promising scaffold to accommodate S for achievi ng high performa nee Li/S battery. Nano sheet activation is used as a viable strategy to induce a micropore system and further improve the battery performance. Accordingly, chemical activation methods dominate despite the need of multiple stages, which slow down the process in addition to making them tiresome. Here, a three-dimensional (3D) N-doped graphene specimen was physically activated with CO2, a clean and single step process, and used for the preparation of a sulfur composite (A-3DNG/S). The A-3DNG/S composite exhibited outstanding electrochemical properties such as an excellent rate capability (1,000 mAh·g^-1 at 2C), high reversible capacity and cycling stability (average capacity ~ 800 mAh·g^-1 at 1C after 200 cycles), values which exceed those measured in chemically activated graphene. Therefore, these results support the use of physical activation as a simple and efficient alternative to improve the performance of carbons as an S host for high-performance Li-S batteries.

关键词： physical activation 3D-graphene solvothermal microwave synthesis Li-S battery

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An egg-shell bifunctional CeO_(2)-modified NiPd/Al_(2) O_(3) catalyst for petrochemical processes involving selective hydrogenation and hydroisomerization

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Journal of Rare Earths 2021年第11期39卷 1382-1388,I0003页

作者： Franklin J.Mendez Javier A.Alves Yahse Rojas-Challa Oscar Corona Yanet Villasana Julia Guerra German Garcia-Colli Osvaldo M.Martinez Joaquin L.Brito Centro de Quimica Instituto Venezolano de Invesdgaciones CientfficasCarretera PanamericanaKm 11 Altos de PipeCaracas1020AVenezuela departamento de Estado Solido Instituto de FisicaUniversidad Nacional Autonoma de MexicoCiudad UniversitariaCiudad de Mexico04510Mexico departamento de ingenieria Quimica Facultad de Ingenieria(UNLP)and Centro de Investigacion y Desarrollo en Ciencias Aplicadas"Dr.J.J.Ronco"(CINDECA)CCT-La Plata-CONICET-UNLPLa Plata1900Argentina departamento de Quimica Analitica Facultad de QufmicaUniversidad Nacional Autonoma de MexicoCiudad UniversitariaCiudad de Mexico04510Mexico instituto Tecnoldgico Venezolano del Petroleo SA. Petrole os de Venezuela SA.Urb.Santa Rosa-Sector El TamborLos Teques1201Venezuela instituto Superior de Formacion Docente Salome Urena Esquina Leonardo D'VinciSanto Domingo10114Republica Dominicana Biomass to Resources Group Universidad Regional Amazonica IkiamKm 7 via MuyunaTena150150Ecuador departamento de Termodinamica y Fenomenos de Transferencia Universidad Simon BolivarValle de SartenejasCaracas1086Venezuela

The catalytic performance during the 1-butyne hydrogenation using two reduced Al_(2) O_(3)-supported Pdbased catalysts was carried out in a total recirculation system with an external fixed-bed *** lab-prepared egg-shell NiPd/CeO_(2)-Al_(2) O_(3) catalyst(NiPdCe) with Pd loading=0.5 wt%,Ni/Pd atomic ratio=1 and CeO_(2) loading=3 wt% was synthesized and characterized,and it was compared with an egg-shell Al_(2) O_(3)-supported Pd based commercial catalyst(PdCC).The reduced catalysts were characterized by X-ray diffraction,X-ray photoelectron spectroscopy,and high-resolution transmission electron *** textural characteristics and ammonia temperature-programmed desorption profiles of the fresh(unreduced) catalysts were also *** catalysts show high 1-butyne conversion and selectivity to 1-butene,but the catalysts also present important differences between hydroisomerizing and hydrogenating *** catalyst shows higher capability for hydroisomerization reactions,while the PdCC catalyst exhibits higher hydrogenating *** observed catalytic performances can be interesting for some industrial processes and can provide a guideline for the development of a Pd-based catalyst with specific catalytic properties.

关键词： 1-Butyne Bifunctional catalyst Egg-shell Hydrogenation Hydroisomerization NiPd catalyst

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