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Will climate change amplify epidemics and give rise to pandemics

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四川生理科学杂志 2023年第9期45卷 1643-1643页

作者： tulio de Oliveira Centre for Epidemic Response and Innovation (CERI) at Stellenbosch University Stellenbosch South Africa.

While the world recovers from the COVID-19 pandemic,another crisis continues to spiral at a much faster speed than was *** change is dominating our lives and causing a high level of *** all over the world are struggling to survive the damage caused by extreme *** are trying to control wildfires,rebuild roads andhouses damaged by floods,and learn to survive in a hotter and more dangerous ***,there is also a new threat that is being overlooked-the interaction between climate change and infectious diseases.A comprehensive meta-analysis revealed that climate change could aggravate more than 50%of known human ***,this is happening now.

关键词： climate floods extreme

Thermal Characterization and Lifetime Estimation of the Humus Lombricospt

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American Journal of Analytical Chemistry 2014年第2期5卷 45-49页

作者： tulio Andres Florez Gladis Miriam Aparicio Ginsai Group Universidad Autónoma de Occidente Cali Colombia

Through this study, the humus produced in the breeding place of Universidad Autonoma de Occidente was thermally characterized. The humus was submitted to a heating program controlled by the Differential Scanning Calorimetry (DSC) technique to characterize the type of transition, Thermogravimetry (TGA) to study the equilibrium of phasesand Mass Spectrometry (MS) coupled to TGA to identify detached elements in a temperature range. The temperature range used in this study was 30℃ ℃. The energy required for the water desorption in the humus has been found in this study. The humus showed a quick desorption between 30℃ ≤ TDesorption ≤ 110℃ at a heating rate of 10℃/min and presented decomposition around 250℃. Moreover, the kinetics of the desorption of the humus was studied to obtain the activation energy three TGA measures for three different heating rates. The average activation energy was about 26 kJ/Mol. This result was carried out to obtain an estimation of the desorption time of water in the range from room temperature to the decomposition temperature around 350℃.

关键词： Thermal Analysis Thermogravimetry (TGA) Differential Scanning Calorimetry (DSC) Mass Spectrometry (MS) Activation Energy Decomposition Kinetics Humus

Amphibian richness along modified riparian areas of central Mexico:conservation priorities

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Ecological Processes 2022年第1期11卷 902-915页

作者： Marco tulio Oropeza‑Sánchez Ireri Suazo‑Ortuño Julieta Benítez‑Malvido Erandi Monroy‑Hernández Roberto Munguía‑Steyer Instituto de Investigaciones en Ecosistemas y Sustentabilidad(IIES) Universidad Nacional Autónoma de MéxicoAntigua Carretera a Pátzcuaro 8701CP 58190 MoreliaMichoacánMexico Instituto de Investigaciones Sobre los Recursos Naturales(INIRENA) Universidad Michoacana de San Nicolás de HidalgoAv.San Juanito Itzícuaro S/NCP 58330 MoreliaMichoacánMexico Facultad de Estudios Superiores Iztacala(FES‑Iztacala) Universidad Nacional Autónoma de MéxicoAv.de los Barrios No.1CP 54090 Tlalnepantla de BazEstado de MéxicoMexico.

Background:Land‑use change frequently affects faunistic populations and *** achieve successful conservation strategies,we need suitable information about species distribution and the causes of extinction *** amphibian species depend on riparian vegetation to complete their life *** 41%of amphibian species are globally threatened,and accurate estimations of population size,species richness and the identification of critical habitats are urgently needed *** evaluate the magnitude of changes in species richness and demography,estimations that include detection probability are *** this study,we employed multi‑species occupancy models to estimate detection probability and the effect of land cover type(i.e.,cropland,artificial pasture,secondary and mature forest)in a 500‑m radius on the occupancy probability and richness of diurnal amphibians in 60 riparian zones in the state of Michoacán in central ***,we evaluated the potential of the endemic salamander Ambystoma ordinarium as a flagship species for the conservation of other native amphibian ***:We registered a total of 20 amphibian species in the diurnal assemblage,of which 10 species are considered at risk of *** found that cropland was the most important land‑use type for explaining amphibian distribu‑tion in riparian zones,with negative effects on most amphibian *** found no differences in species richness between zones with and without *** riparian zones occupied by ***,however,we found a higher number of species at risk of ***:Our findings showed negative effects of croplands on the distribution of most amphibian *** riparian zones are important for the maintenance of native diurnal amphibian communities and *** can act as a flagship species for the conservation of threatened amphibian species.

关键词： Flagship species Habitat quality Occupancy models Salamanders Threatened species

Studies of the Volatile Compounds Present in Leaves, Stems and Flowers of <i>Vernonanthura patens</i>(Kunth) H. Rob

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International Journal of Organic Chemistry 2014年第5期4卷 314-318页

作者： Patricia Manzano Migdalia Miranda tulio Orellana Maria Quijano Superior Polytechnic School of Litoral Biotechnology Research Center of Ecuador (ESPOL-CIBE) Guayaquil Ecuador Faculty of Natural Sciences and Mathematics of Superior Polytechnic School of Litoral Guayaquil Ecuador

The study of the volatile components of the leaves, stems and flowers of Vernonanthura patens is discussed. A micro solid-phase extraction at constant temperature with a dimethylsiloxane fiber of 100 μm was performed. The compounds extracted were analyzed by gas chromatography coupled to mass spectrometry (GC-MS). 7 monoterpenes structures were assigned to leaves, and three to stems, these compounds were not detected in the flowers with the configuration of the system used. 17 sesquiterpenes were identified in the leaves;6 in stems and 2 in flowers, finding coincidence in some of them. The major components were α-humulene in leaves, bergamotene in stems and caryophyllene in flowers.

关键词： V. patens Volatile Bergamotene Caryophyllene α-Humulene

Finite Element Method Applied to the Eigenvalue Analysis of Flexible Rotors Supported by Journal Bearings

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Engineering（科研） 2014年第3期6卷 127-137页

作者： Wéderley M. Miranda Marco tulio C. Faria Centro Universitário UNA Belo Horizonte Brazil Universidade Federal de Minas Gerais Belo Horizonte Brazil

This work deals with a finite element procedure developed to perform the eigenvalue analysis of damped gyroscopic systems, represented by flexible rotors supported on fluid film journal bearings. The rotor finite element model is based on the Timoshenko beam theory, accounting for the shaft rotary inertia and gyroscopic moments. The governing equations for the hydrodynamic journal bearing are obtained through the Galerkin weighted residual method applied to the classical Reynolds equation. A perturbation scheme on the fluid film governing equation permits to obtain the zero-th and first order lubrication equations for the bearings, which allow the computation of the dynamic force coefficients associated with the bearing stiffness and damping. The rotor-bearing system equation, which consists of a case of damped gyroscopic equation, is rewritten on state form to compute the complex eigenvalues. The natural frequencies at several operating conditions are obtained and compared to the technical literature data. The influence of the effective damping on the eigenvalue real part sign is analyzed for some examples of rotor-bearing systems, showing how the stability conditions can be predicted by the eigenvalue analysis. The procedure implemented in this work can provide useful guidelines and technical data about the selection of the more appropriate set of bearing parameters for rotating machines operating at stringent conditions.

关键词： Flexible Rotors Fluid Film Bearings Rotor-Bearing Systems Finite Element Eigenvalue Problem

Synthesis and Characterization of Free and Copper (II) Complex of N,N′-<i>Bis</i>(Salicylidene)Ethylenediamine for Application in Dye Sensitized Solar Cells

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Journal of Materials Science and Chemical Engineering 2017年第6期5卷 46-66页

作者： William Ghann Hany Sobhi Hyeonggon Kang tulio Chavez-Gil Fred Nesbitt Jamal Uddin Center for Nanotechnology Department of Natural Sciences Coppin State University Baltimore MD USA Coppin Center for Organic Synthesis Department of Natural Sciences Coppin State University Baltimore MD USA Inorganic and Physical Chemistry Lab Department of Natural Sciences Coppin State University Baltimore MD USA

Dye sensitized solar cell represents a promising method for the conversion of solar energy to electric energy. In the present work free N,N'-bis(salicyli-dene)ethylenediamine and its copper (II) complex were synthesized, characterized, and investigated for use as dye sensitizers in the fabrication of dye sensitized solar cells. The dyes were characterized using UV-Vis, Steady State Florescence, and Fluorescence Lifetime, Thermogravimetric Analysis, Differential Scanning Calorimetry, and Cyclic Voltammetry. The thermogravimetric analyses of the ligand and the ligand Copper complex demonstrate the stabilizing effect of the copper ion on the ligand complex. Additionally, the copper ion is shown to stabilize the structure, as evidenced by the 150oC increase in the extrapolated onset temperature of the decomposition event. The ligand copper complex is further stabilized by the presence of the copper, which is determined by the 6.34% residue that remained at the end of the thermogravimetric analysis, compared with 0% residue when applying the same condition for the ligand without copper. The current-voltage characteristics of the cells and the electrochemical impedance were determined. The photovoltaic performance of the solar cell devices fabricated using N,N'-bis(salicylidene) ethylenediamine dye was found to be slightly better than those produced from the copper complex. The solar to electric power efficiency of the ligand-based dye sensitized solar cell was 0.14% and that of the copper complex was found to 0.12%. Although the difference in the cell efficiency is quite small, it is obvious that the insertion of Copper into the ligand did not enhance the performance of the solar cells. The photocurrent-photovoltage results are consistent with the absorption spectra that showed a more prominent band for the ligand. The free hydroxyl groups, present in the ligand but absent from the copper complex owing to their coordination with the copper metal, could be responsible for

关键词： DSSC Copper N N'-Bis(Salicylidene)Ethylenediamine Dye Titanium Dioxide

On the Bump Tests of Cracked Shafts Using Acoustic Emission Techniques

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Engineering（科研） 2016年第9期8卷 572-581页

作者： Gilberto Luiz S. Pimentel-Junior Frederico B. Oliveira Marco tulio C. Faria Department of Mechanical Engineering Universidade Federal de Minas Gerais Belo Horizonte Brazil

An investigation about the application of Acoustic Emission (AE) techniques to analyze the dynamic response of different cracked shafts rendered in bump tests is presented in this work. The experimental apparatus devised for this work complies of six shafts with different transverse crack sizes and a high-frequency data acquisition system. The AE signals generated in the bump tests performed on the different cracked shafts are captured by a wideband AE transducer. Those signals are treated by using statistical moments, wavelet transforms, and frequency- and time-domain procedures. A transverse crack of predetermined depth is etched into each shaft. The experimental results show that the values of kurtosis and skewness estimated for the AE signals can be used to identify the crack size.

关键词： Acoustic Emission Cracked Rotors Bump Tests Shaft Crack

Cementitious Composites Containing Multifunctional Sugarcane Fibres

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Journal of Building Material Science 2019年第2期1卷 1-8页

作者： Viviane VSGuilarduci Patricia Benedini Martelli Honória de Fátima Gorgulho Pablo Resende Oliveira tulio Hallak Panzera Núcleo de Ambiente Saúde e SegurançaIF Sudeste MGSão João del-ReiBrazil Department of Natural Sciences–DCNAT Federal University of São João Del-Rei-UFSJBrazil Centre for Innovation and Technology in Composite Materials–CITeC Department of Mechanical EngineeringFederal University of São João Del-Rei-UFSJBrazil

This work investigates the reuse of natural(SCB)and minopropyltriethoxysilanemodifed(MSCB)sugarcane bagasse fbres in cementitious *** bagasse fbres are pre-used in the treatment of motor oil contaminated effluents.A full factorial design is used to identify the effects of fbre type(SCB and MSCB),fbre length(0.6 and 1.2 mm),fbre amount(1 and 2 wt%)and fbre condition(before and after oil filtration)on apparent density,water absorption,apparent porosity,ultra-pulse velocity,dynamic modulus,flexural strength and *** fibres lead to increased apparent density compared to MSCB fibre reinforced *** fibres contribute to reduce composite porosity,leading to higher mechanical *** smaller area of MSCB fibres promotes a larger amount of cementitious phase per unit volume,thus increasing the strength of the *** sugarcane fbres(1.2 mm)have a larger surface area,leading to a higher fibre concentration per unit volume,which increases water *** amount of fibre has no significant effect on mechanical and physical *** made with 2 wt%0.6 mm long MSCB fibres achieve promising results for non-structural civil engineering applications.

关键词： Sugarcane bagasse Treatment of effluents Chemical treatment Cementitious composites Mechanical properties Non-destructive test Design of experiment

Importance of computed tomography in posterior malleolar fractures:Added information to preoperative X-ray studies

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World Journal of Orthopedics 2023年第12期14卷 868-877页

作者： NoéDe Marchi Neto Pietro Felice Tomazini Nesello Jordanna Maria Bergamasco Marco tulio Costa Ralph Walter Christian Nilson Roberto Severino Severino Department of Orthopedics and Traumatology of the São Paulo Mercy Hospital(Santa Casa de São Paulo)-Fernandinho Simonsen PavillionFaculdade de Ciências Médicas da Santa Casa de São Paulo-BrazilSão Paulo 01221-020Brazil

BACKGROUND Ankle fractures are common lesions of the lower *** 40%of ankle fractures affect the posterior malleolus(PM).Historically,PM osteosynthesis was recommended when PM size in X-ray images was greater than 25%of the ***,computed tomography(CT)has been gaining traction in the preoperative evaluation of ankle *** To elucidate the similarity in dimensions and to correlate PM size in X-ray images with the articular surface of the affected tibial plafond in the axial view on CT(AXCT)of a PM *** Eighty-one patients(mean age:39.4±13.5 years)were evaluated(54.3%were male).Two independent examiners measured PM size in profile X-ray images(PMXR)and sagittal CT(SAGCT)*** correlation of the measurements between the examiners and the difference in the PM fragment sizes between the two images were ***,the PM size in PMXR was compared with the surface of the tibial plafond involved in the fracture in AXCT according to the Haraguchi *** The correlation rates between the examiners were 0.93 and 0.94 for PMXR and SAGCT,respectively(PI>III(P<0.001).CONCLUSION PM fractures show different sizes using X-ray or CT *** showed a larger PM in the sagittal plane and allowed the visualization of the real dimensions of the tibial plafond surface.

关键词： Ankle fracture Posterior malleolar fracture Computed tomography X-ray Posterior malleolus fracture Trimalleolar facture