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American Journal of Plant Sciences 2019年第2期10卷 339-350页

作者： Francielli D’Carlos Cravo Wilder Douglas Santiago Allan da Silva Lunguinho Richard Bispo Barbosa Renan Elan da Silva Oliveira Gabriela Fontes Alvarenga stephano daniel santos Rafaella Hilda Zaniti Souza Ellen Cristina de Souza Katia Julia de Almeida Josefina Aparecida de Souza David Lee Nelson Maria das Gracas Cardoso Department of Food Science Federal University of LavrasC.P.LavrasMinas GeraisBrazil Department of Chemistry Federal University of LavrasC.P.LavrasMinas GeraisBrazil Pro-Reitoria de Pesquisa e Pos-Graduacao Federal University of Vales de Jequitinhonha and MucuriDiamantinaMGBrazil

The present work sought to characterize the cyanogenic glycoside dhurrin in five sugarcane varieties and to determine its possible relationship with the formation of ethyl carbamate in cachaca. For each variety, methanol, ethyl acetate and hexane extracts were prepared and submitted to thin layer chromatography. Chromatographic spots were revealed with iodine vapors. The physical and chemical parameters of the spirits produced from the five different varieties of sugar cane and by different production processes were within the legal limits. Although not exceeding the limit for ethyl carbamate, a significant variation in the final concentration of this compound was observed for each sample analyzed. The Rf values for the dhurrin standard and for the sugarcane variety SP 83-2847 were equal, similar to those for SP 80-3280 and CTC 11 and different from the Rf values for the RB 86-7515 and IAC 86-2480 samples.

关键词： Cachaca Ethyl Carbamate Quality Glycosides Cyanide Dhurrin

Tribological performance of uncoated and TiCN-coated D2,M2 and M4 steels under lubricated condition

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Journal of Iron and Steel Research International 2017年第8期24卷 823-829页

作者： Luis daniel Aguilera Camacho santos García Miranda Karla Judith Moreno Instituto Tecnologico de Celaya/TNM Apartado Postal 5738010-CelayaGuanajuatoMexico

Hard coatings are used to improve the wear resistance of metals which largely depends on adhesion between substrate and *** wear and friction behavior of uncoated and TiCN-coated D2,M2 and M4 steels were evaluated by apin-on-disk test under lubricated *** order to evaluate the influence of lubricant on wear performance,dry friction tests were also *** results showed that friction coefficients were very similar for both uncoated and TiCN-coated *** lubricated conditions,the uncoated D2 tool steel exhibited the lowest friction coefficient,but the TiCN-coated D2 steel presented the smallest wear *** was the main wear mechanism in all the ***,microhardness measurements were carried out,finding an influence of the steel substrate on the hardness of the ***,adhesion test was conducted,suggesting agood adhesion of class 1 between substrates and TiCN coatings.

关键词： D2 tool steel M2 high speed steel M4 high speed steel TiCN coating Friction Wear

Elevation transition of aquatic insects closely matches a thermal feature in the Yungas of Northwestern Argentina

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Journal of Mountain Science 2024年第2期21卷 433-448页

作者： Alexandra BUITRAGO-GUACANAME Carlos MOLINERI Andrés LIRA-NORIEGA daniel Andrés DOS santos Neotropical Biodiversity Institute(CONICET-UNT) UNT-DomesHorco Molle S/N4107 TucumánArgentina CONACYT Research Fellow Network of Advanced Molecular StudiesInstitute of Ecology A.COld Road to Coatepec 351El HayaCP 91073XalapaVeracruzMexico Biostatistics Chair Faculty of Natural Sciences and IMLNational University of TucumánSan Miguel de TucumánMiguel Lillo 2054000 TucumánArgentina

Temperature is a key factor that shapes the distribution of *** knowledge about how species respond to temperature is relevant to devise strategies for addressing the impacts of climate *** insects are particularly vulnerable to climate change,yet there is still much to learn about their ecology and *** the Yungas ecoregion of Northwestern Argentina,cold-and warm-adapted species of the orders Ephemeroptera,Plecoptera,and Trichoptera(EPT)are segregated by *** modeled the ecological niche of South American EPT species in this region using available data and projected their potential distribution in geographic *** were grouped based on their ecogeographic similarity,and we analyzed their replacement pattern along elevation gradients,focusing on the ecotone where opposing thermal preferences *** this interface,we identified critical points where the combined incidence of cold and warm assemblages maximizes,indicating a significant transition *** found that the Montane Cloud Forest holds the interface,with a particularly greater suitability at its lower *** main axis of the interface runs in a N-S direction and falls between 14°C-16°C mean annual *** probability of a particular location within a basin being classified as part of the interface increases as Kira’s warmth index approaches a score around *** the interface is critical for defining the thermal limits of species distribution and designing biomonitoring *** in the location of thermal constants related to mountainous ecotones may cause vertical displacement of aquatic insects and vegetation *** have recognized significant temperature thresholds that serve as indicators of suitability for the *** global warming is anticipated to shift these indicators,we suggest using them to monitor the imprints of climate change on mountain ecosystems.

关键词： Austral Yungas Ecological Niche Model Ephemeroptera Kira’s warmth index Plecoptera Trichoptera

Electromagnetic Characterization of Recyclable Polymer Nanofibers Based on PSU/Carbonyl Iron

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Journal of Renewable Materials 2019年第3期7卷 279-287页

作者： daniel Consoli Silveira Tiago Teixeira da Silva Braga daniel Molina Gil Newton Adriano dos santos Gomes Lilia Müller Guerrini Edson Cocchieri Botelho Department of Materials and Technology Sao Paulo State University(UNESP)School of EngineeringGuaratinguetá/SP-Brazil Electronic Warfare Laboratory Technological Institute of Aeronautics(ITA)Sao Josédos Campos/SP-Brazil Institute of Science and Technology Federal University of Sao Paulo(UNIFESP)Sao Josédos Campos/SP-Brazil

This study investigated and defined the optimal processing parameters for the electrospinning of polysulfone polymer solutions with N,*** of parameters such as solute concentration,electrical voltage,and working distance were correlated with the quality of the obtained nanofibers using morphological characterization via scanning electron microscopy(SEM).Carbonyl iron additive was dispersed in the polymer solutions,using ultrasonic tip,and the material processed via electrospinning with aforementioned parameters *** with the property of interaction with electromagnetic waves were *** dispersion of different concentrations of the additive and electromagnetic characterizations in the X-band of microwaves(8.2 and 12.4 GHz),using vector network analyzer(VNA)and rectangular waveguide,allowed the identification of the materials electromagnetic *** parameters allowed the calculation of reflected and transmitted energy by the material.

关键词： Carbonyl iron electromagnetic characterization electrospinning nanofibers polysulfone

Can small-scale altitudinal gradients predict spatial and temporal patterns in tropical forests?

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Journal of Forestry Research 2021年第5期32卷 1854-1865页

作者： Mariana Caroline Moreira Morelli Cléber Rodrigo de Souza Jean daniel Morel Vinícius Andrade Maia Alisson Borges Miranda santos Kaline Fernandes Miranda Rubens Manoel dos santos Forest Sciences Department Federal University of LavrasCampus UniversitárioCx.P.3037LavrasMGCEP 37200-000Brazil Department of Biology Federal University of LavrasCampus UniversitárioLavrasMGCEP 37200-000Brazil

In tropical montane forests,compositional and structural changes are commonly driven by broad-scale altitudinal ***,given the lack of knowledge on small-scale vegetation changes and temporal dynamics,we address the effects of small-scale variations in soil and altitude on tree community structure,temporal dynamics and phylogenetic diversity in a semi-deciduous tropical forest of the Atlantic Forest Domain,southeastern *** 2010 and 2015 we sampled thirty plots of 400 m^(2),set up along an altitudinal gradient between 1000 and 1500 m a.s.I..In each plot,we collected soil samples for chemical and textural *** fitted linear models to test the effects of altitude and soil on community dynamics and phylogenetic *** and soil explained the spatial variation in number of individuals and phylogenetic diversity *** lower to higher altitudes,we found decreasing fertility,increasing tree density and decreasing phylogenetic *** significantly influenced the increases in total biomass(from 240.9 to 255.4 t ha^(-1))and individual biomass(from 0.15 to 0.17 t)recorded in the *** while community temporal dynamics had rates of 1.96%for mortality,1.02%for recruitment,1.61%for biomass loss and 2.81%for biomass gain,none of them were explained by altitude or *** species substitution averaged0.1 in the ***,these results suggest that the small-scale variations in altitude and soil likely determine the conditions and resources that drive community assembly and structure,which are expressed by spatial variations along the altitudinal *** the same time,temporal patterns were not influenced by altitude-related environmental variation,resulting in a similar dynamic behaviour across the gradient,suggesting that broad-scale factors may play a more important role than local ones.

关键词： Fine-scale Semideciduous forests Montane forests Dynamic patterns

Relaxant effect and possible mechanism of 17-nor-subincanadine E in rabbit corpora cavernosa

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Asian Journal of Andrology 2011年第5期13卷 747-753页

作者： Otacilio D Benvindo Nilberto RF Nascimento Claudia F santos Manasses C Fonteles Edilberto R Silveira daniel E Uchoa Adriana R Campos Karina MA Cunha Flavia A santos Vietla S Rao Department of Physiology and Pharmacology Faculty of Medicine Federal University of Ceara PO Box 3157 60430-270 Fortaleza CE Brazil Superior Institute of Biomedicine Caara State University Fortaleza CE Brazil Detriment of Organic and Inorganic Chemistry Federal University of Ceara 60455-760 Fortaleza CE Brazil

Compounds with dual action on cyclic adenosine monophosphate （cAMP） and cyclic guanosine monophosphate （cGMP） may be a treatment option for erectile dysfunction, as they not only promote penile erection but also prevent the upregulation of phosphodiesterase-5. In this study, we examined the possible relaxant effect and mechanism of 17-nor-subincanadine E （SEC, 0.2-200 pmol I^-1）, a plant-derived alkaloid, in rabbit corpus cavernosum （RbCC） strips that had been precontracted by exposure to phenylephrine （10 pmol I^- 1） or a high concentration of K＋（60 mmol I^- 1） in vitro. In addition to SEC＇s effect on cAMP and cGMP levels, electrical field stimulation （EFS） in phenylephrine-precontracted RbCC and calcium chloride （1-100 mmol I^-1） evoked responses in depolarized RbCC were analysed. SEC relaxed the phenylephrine-precontracted RbCCs in a concentration-dependent manner. Atropine, guanethidine and N-co-nitro-L-arginine methyl ester （L-NAME） did not have any effect on the relaxation of RBCCs. When 1H-1,2,4oxadiazole[4,3-a] quinoxalin-1-one （ODQ） was added, it effectively blocked the relaxant response of SEC. Although SEC enhanced the maximal relaxation produced by sodium nitroprusside （SNP） and forskolin in phenylephrine-precontracted cavernosal smooth muscle, it caused a decrease in the maximal contractile response induced by calcium chloride in depolarized RbCCs. The relaxant effect of SEC was paralleled by an increase in the tissue levels of the Cyclic nucleotides cAMP and cGMP. We conclude that SEC promotes the relaxation of RbCC, possibly favouring cAMP and cGMP accumulation and calcium blockade. This novel mechanism could be useful for patients who do not benefit from phosphodiesterase inhibitors and for those with endothelial and nitrergic dysfunction, such as patients with diabetes, hypertension and dyslipidaemias.

关键词： 17-nor-subincanadine E cyclic nucleotides electrical field stimulation nitric oxide rabbit corpus cavernosum smoothmuscle relaxation

Small-scale edaphic heterogeneity as a floristic-structural complexity driver in Seasonally Dry Tropical Forests tree communities

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Journal of Forestry Research 2020年第6期31卷 2347-2357页

作者： Cle´ber Rodrigo de Souza Jean daniel Morel Alisson Borges Miranda santos Wilder Bento da Silva Vinı´cius Andrade Maia Polyanne Aparecida Coelho Vanessa Leite Rezende Rubens Manoel dos santos Forest Sciences Departament Federal University of LavrasCx.P.3037Lavras 37200-000Brazil Biology Department Federal University of LavrasCx.P.3037Lavras 37200-000Brazil

Our work aimed to test the hypothesis that soil microscale heterogeneity act as a community ecological driver,increasing diversity and promoting structural shifts on the Seasonally Dry Tropical Forest(SDTF)tree *** evaluated the relationship between microscale edaphic variations and floristic–structural patterns of tree communities in a SDTF fragment located in the southern end of the Brazilian Caatinga *** and soil data were obtained through 27 sample units of 400 m2(20 m 920 m),within each one we measured and identified at species level all arboreal individuals with Circumference at the Breast Height greater or equal to 10 cm,and also collected the soil *** the data we evaluated soil variation influence on the tree community structural and floristic patterns trough generalized linear *** explained the small-scale structural and floristic variations,contributing significantly to biomass,sprouting and to floristic relationships between sample *** was also observed a possible relation of the result with the Caatinga domain biogeographic history,due the presence of Sedimentary Caatinga species,which are not expected for the study *** plays an important role in driving small-scale complexity and diversity of SDTF,but we also suggest that Caatinga biogeographic events have influence on the high heterogeneity patterns.

关键词： Caatinga domain Edaphic variables Sprouting Sedimentary Caatinga

Hematological reference values and animal welfare parameters of BALB/C-FMABC (Mus musculus) inoculated with Ehrlich tumor kept in the vivarium at ABC Medical School

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Animal Models and Experimental Medicine 2020年第1期3卷 32-39页

作者： Patrick Gabriel dos santos Pessini Paula Regina Knox de Souza Camila dos santos Chagas Emily Garcia Sampaio daniel santos Neves Giuliana Petri Fernando Luiz Affonso Fonseca Emerson Barbosa da Silva Clinical Analysis Laboratory of the ABC University Health Center Santo AndreBrazil Health Sciences Institute/Paulista University–UNIP Sao PauloBrazil

Background:Biochemical and hematological parameters are important tools for assessing the physiological profile of vital organs,and can be recorded to create reference values used for clinical diagnosis of *** research laboratories lack the means to establish their own set of reference parameters for use in their research,and while there are articles in the literature that discuss laboratory parameters for healthy BALB/c mice,few studies address the evaluation of these parameters in pathological situations,such as in mice inoculated with Ehrlich ***:BALB/c-FMABC mice previously inoculated with Ehrlich tumor were maintained under appropriate *** samples were taken for analysis of hematological parameters using automated and semi-automated equipment to create a set of the animal welfare parameters for ***:Results were obtained for all the hematological parameters for all groups *** showed:statistically significant differences between the initial and final tumor weight;comparable initial tumour volume and weight;an increase in leukocytes in the 7-day group with a characteristic predominance of lymphocytes and neutrophils;statistically significant changes in RDW in the 21-day group and in the welfare parameters in the 28-day ***:The study successfully defined and established reference values for hematological and welfare parameters for all groups analyzed.

关键词： ehrlich tumor carcinoma experimental animal model reference value welfare

Hydrological variability and long-term floristic-structural modifications in different habitats of a tropical semi-deciduous forest

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Journal of Forestry Research 2022年第3期33卷 801-811页

作者： Alisson Borges Miranda santos Vinicius Andrade Maia Cléber Rodrigo de Souza Natália de Aguiar-Campos Aurélio de Jesus Rodrigues Pais Wilder Bento da Silva Nathalle Cristine Alencar Fagundes Jean daniel Morel Rubens Manoel dos santos Department of Forestry Sciences Federal University of LavrasCampus UniversitárioC.P.3037LavrasBrazil Faculty of Environmental Engineering and Natural Resources Zambeze UniversityChimoioC.P.2400Mozambique Biological Sciences Universidade do Estado de Minas GeraisUnidade ItuiutabaAv.Antônio Carlos 6627Ituiutaba31270-901Brazil Department of Biology Federal University of LavrasUniversity campusC.P.3037Lavras37200-000Brazil

Shifts in hydrological regimes alter river flow rates and flood pulses, decrease environmental heterogeneity and the floristic-structural complexity of associated plant communities. We tested the hypothesis that drought events affect plant community composition and structure at a small-scale within a riparian fragment towards a reduction in floristic-structural complexity. The tree community was sampled in three habitats (wet, transitional and dry) and monitored in seven inventories carried out between 1991 and 2018. Hydrological variations were evaluated through annual rainfalls, river flow rates and water level data. The species richness and the detrended correspondence analysis axes were used to characterise the temporal modifications in floristic composition. Community structure was described in terms of biomass: accumulated, growth of survivors, mortality and recruitment. Generalised linear mixed models were fitted to evaluate the effects of time and environment in community. It was concluded that the climate has become drier in recent years due to declining precipitation that has affected flow rates and water levels. The floristic-structural complexity of the study fragment was maintained during the monitoring period. However, prolonged and extreme drought events displayed the potential to impact floristic-structural patterns.

关键词： Forest dynamics Climate changes Semi-deciduous seasonal forest Temporal change Functioning communities

Composite Dose Distribution Verification Support for Accuracy of Dynamical Arc-IMRT Treatment Delivery

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Composite Dose Distribution Verification Support for Accurac...