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Investigation of Galactic open cluster remnants： the case of NGC 7193

Research in Astronomy and Astrophysics 2017年第1期17卷 31-54页

作者： Mateus de Souza Angelo Joao Francisco Coelho dos Santos jr Wagner Jose Barbosa Corradi Francisco Ferreira de Souza Maia Andres Eduardo Piatti Departamento de Fisica ICEx Universidade Federal de Minas Gerais Av. Antonio Carlos 6627 31270-901 Belo Horizonte MG Brazil Observatorio Astronomico Universidad Nacional de Cordoba Laprida 854 5000 Cordoba Argentina Consejo Nacional de Investigaciones Cientificas y Tecnicas Av. Rivadavia 1917 C1033AAJ Buenos AiresArgentina

Galactic open clusters （OCs） that survive the early gas-expulsion phase are gradually de- stroyed over time by the action of disruptive dynamical processes. Their final evolutionary stages are characterized by a poorly populated concentration of stars called an open cluster remnant （OCR）. This study is devoted to assessing the real physical nature of the OCR candidate NGC 7193. GMOS/Gemini spectroscopy of 53 stars in the inner target region were obtained to derive radial velocities and at- mospheric parameters. We also employed photometric and proper motion data. The analysis method consists of the following steps：（i） analysis of the statistical resemblance between the cluster and a set of field samples with respect to the sequences defined in color-magnitude diagrams （CMDs）; （ii） a 5-dimensional iterative exclusion routine was employed to identify outliers from kinematical and posi- tional data; （iii） isochrone fitting to thes× （J - Ks） CMD of the remaining stars and the dispersion of spectral types along empirical sequences in the （J - H） × （H - Ks） diagram were checked. A group of stars was identified for which the mean heliocentric distance is compatible with that obtained via isochrone fitting and whose metallicities are compatible with each other. Fifteen of the member stars observed spectroscopically were identified together with another 19 probable members. Our results indi- cate that NGC 7193 is a genuine OCR, of a once very populous OC, for which the following parameters were derived： d = 501±46 pc, t = 2.5±1.2 Gyr, （[Fe/H]） = -0.17±0.23 and E（B-V） = 0.05±0.05. Its luminosity and mass functions show depletion of low mass stars, confirming the OCR is in a dynam- ically evolved state.

关键词： open cluster remnants - Galactic open clusters

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Avian Community Density and Distribution Patterns among Nicaraguan Conventional and Organic Shade-Coffee Plantations

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Agricultural Sciences 2020年第1期11卷 27-53页

作者： Wayne J. Arendt R. Cary Tuckfield Juan carlos Martínez-Sánchez Jennifer L. Reidy Frank R. Thompson III Joseph M. Wunderle jr. José Manuel Zolotoff USDA Forest Service International Institute of Tropical Forestry Sabana Field Research Station Luquillo PR USA ECOSTATys LLC Aiken SC USA Fundación Cocibolca Managua Nicaragua Department of Biology University of Washington Seattle WA USA Department of Fisheries and Wildlife Sciences 302 Anheuser-Busch Natural Resources Building University of Missouri Columbia MO USA North Central Research Station 202 Anheuser-Busch Natural Resources Building University of Missouri Columbia MO USA

We used a distance-sampling survey method and multivariate statistics to obtain a unique estimate of bird species density and seasonal variation in shade-coffee plantations. Our aim was to determine which cultivation practices among plantations contribute most to bird abundance. We conducted avian species counts at 200 points distributed across 10 shade-coffee plantations bordering the lower slopes of the Mombacho Volcano Natural Reserve, in western Nicaragua. We measured vegetation structure (coffee plants and overstory). We used principal components analysis (PCA) among 14 habitat variables to derive a single phyto-geoclimate summary measure (PGSM). We also used PCA to derive an avian abundance summary measure (AASM) from three bird survey variables, which proved to be a good predictor of bird density. We found higher bird species densities (AASM) in organic and traditional polyculture shade coffee plantations whose structurally complex and diverse overstory could be verified by PGSM. However, this finding was true only for birds that were habitat specialists. Our results provide further evidence for promoting organic coffee cultivation practices that maintain a structurally diverse overstory and help retain avian species richness and abundance in coffee plantations.

关键词： Bird Density Coffee Cultivation Practices Monoculture Organic Polyculture Spatial Distribution Species Richness

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The Biology of <i>Szelenyiopria talitae</i>(Hymenoptera: Diapriidae): Larval Parasitoid of the Leaf-Cutting Ant <i>Acromyrmex subterraneus</i>(Hymenoptera: Formicidae)

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Advances in Entomology 2021年第3期9卷 131-145页

作者： Thalles Cardoso Mattoso Denise Delores Oliveira Moreira Thais Berçot Pontes Teodoro Claudio Luiz Moreira de Souza Rita de Kássia Guarnier da Silva Veronica de Morais carlos Peres Silva Milton Erthal jr. Richard Ian Samuels Laboratório de Entomologia e Fitopatologia Universidade Estadual do Norte Fluminense Darcy Ribeiro Campos dos Goytacazes Rio de Janeiro Brazil Universidade Candido Mendes Campos dos Goytacazes Rio de Janeiro Brazil Departamento de Bioquímica Universidade Federal de Santa Catarina Florianópolis Brazil Instituto Federal Fluminense Campos dos Goytacazes Rio de Janeiro Brazil

The biology of a koinobiont parasitoid of leaf-cutting ant larvae, Szelenyiopria talitae (Hymenoptera: Diapriidae), was studied from naturally infested Acromyrmex subterraneus (Hymenoptera: Formicidae) nests. Nests were collected in the field from the Atlantic rainforest biome in the state of Rio de Janeiro. A total of fifty-three nests were collected from 2015 to 2018. Parasitized nests were only found during the months of September and October. Approximately 22% of the nests collected over a four-year period were found to have been parasitized by S. talitae. The mean within-nest parasitism rate was 66.3%. This diapriid displayed both solitary (14%) and gregarious parasitism (86%), with up to a maximum of 12 parasitoids developing within a single host. Gregarious parasitism with two (29%) or three (21%) S. talitae per host was most frequently observed. There was a positive correlation between the number of parasitoids per host and host size (dry weight), indicating that S. talitae females oviposited a higher number of eggs in larger hosts. There was also a negative correlation between S. talitae<

关键词： Formicidae Leaf Cutting Ant Pest Koinobiont

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Perspectives of nano-carrier drug delivery systems to overcome cancer drug resistance in the clinics

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Cancer Drug Resistance 2021年第1期4卷 44-68页

作者： Anna Ulldemolins Joaquin Seras-Franzoso Fernanda Andrade Diana Rafael Ibane Abasolo Petra Gener Simo Schwartz jr Drug Delivery and Targeting Group Molecular Biology and Biochemistry Research Centre for Nanomedicine(CIBBIM-Nanomedicine)Vall d’Hebron Institut de RecercaUniversitat Autonoma de BarcelonaBarcelona 08035Spain Networking Research Centre for Bioengineering Biomaterialsand Nanomedicine(CIBER-BBN)Instituto de Salud Carlos IIIZaragoza 50009Spain

Advanced cancer is still considered an incurable disease because of its metastatic spread to distal organs and progressive gain of *** though considerable treatment progress and more effective therapies have been achieved over the past years,recurrence in the long-term and undesired side effects are still the main drawbacks of current clinical ***,a majority of chemotherapeutic drugs are highly hydrophobic and need to be diluted in organic solvents,which cause high toxicity,in order to reach effective therapeutic *** limitations of conventional cancer therapies prompted the use of nanomedicine,the medical application of nanotechnology,to provide more effective and safer cancer *** of nanomedicines to overcome resistance,ameliorate solubility,improve pharmacological profile,and reduce adverse effects of chemotherapeutical drugs is thus highly *** use in the clinical setting has increased over the last *** the various existing nanosystems,nanoparticles have the ability to transform conventional medicine by reducing the adverse effects and providing a controlled release of therapeutic ***,their small size facilitates the intracellular ***,we provide a closer review of clinical prospects and mechanisms of action of nanomedicines to overcome drug *** significance of specific targeting towards cancer cells is debated as well.

关键词： Drug delivery systems resistance nanomedicine cancer treatment

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Ursolic Acid Derivatives Induced Apoptosis and Reduces the NF-κB in Human Lung Adenocarcinoma Cells

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Journal of Cancer Therapy 2019年第10期10卷 863-876页

作者： Elaine carlos Scherrer Ydia Mariele Valadares Caio Cesar Souza Alves Gabriella Freitas Ferreira Marcela Pereira Leao Jessica Aline Soares Fernando Sa Silva Alessandra Paula Carli Oswaldo Cardoso jr. Fabiana Simao Machado Sandra Bertelli Ribeiro Castro Life Sciences Institute Federal University of Juiz de ForaGovernador ValadaresMGBrazil Faculty of Medicine Federal University of the Valleys of Jequitinhonha and MucuriTeofilo OtoniMGBrazil Department of Biochemistry and Immunology Federal University of Minas GeraisBelo HorizonteMGBrazil

Lung cancer is the major cause of death in the neoplastic diseases. In spite of the advances in the chemotherapy, the lung cancer treatments are still complex and costly, being necessary the seeking of new drugs. In this context, the ursolic acid (UA) becomes the target of studies that investigate its antitumor potential and, thus, structural modifications can enhance its biological activities. Eight UA semisynthetic derivative compounds (UAD1-8) were synthesized and evaluated their cytotoxic activity against human alveolar adenocarcinoma cells (A549). UAD1, UAD3, UAD5, UAD6 and UAD8 were able to reduce the viability of the A549 cells. Only UAD1 and UAD6 reduced the viability at 24 h, and only UAD3 didn’t reduce the NF-κB expression. The compound UAD1 showed the greater apoptosis induction. Moreover, the compound UAD1 showed better results than UA in all assays. The present study shows, for the first time, the action of these compounds in the apoptotic effect, in the expression of NF-κB and in the A549 cell line. The ursolic acid derivatives showed substantial results in the apoptosis, cytotoxicity and NF-κB inhibition of A549 cells, and further studies are necessary for the development of possible new therapeutic drugs.

关键词： Ursolic Acid Apoptosis NF-κB A549 Cells Tumoral

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上止点位置时气缸内流动的简化数值方法

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家电科技 2007年第5期233卷 64-66页

作者： F. A. Ribas jr. Embraco Brazil carlos J. Deschamps 刘艳品李红旗 Federal University of Santa Catarina Brazil 北京工业大学

开发了一维数学模拟软件预测曲柄位于上止点(TC)位置、排气阀开启过程中气缸内的可压缩流动的方法。通过有限容积法在计算网格离散微分控制方程,网格根据活塞的运动增大或缩短。采用理想气体假设,利用SIMPLEC算法建立压力与速度场的耦... 详细信息

开发了一维数学模拟软件预测曲柄位于上止点(TC)位置、排气阀开启过程中气缸内的可压缩流动的方法。通过有限容积法在计算网格离散微分控制方程,网格根据活塞的运动增大或缩短。采用理想气体假设,利用SIMPLEC算法建立压力与速度场的耦合。软件与活塞远离上止点时适用的积分公式相结合。新的方法再现了一些不能通过积分方法获得的实验数据显示的物理特征,如加速度和摩擦引起的、沿气缸盖的压力降。

关键词：缸内流动上止点数值方法位置 SIMPLEC算法软件预测计算网格可压缩流动

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A Structure and Antioxidant Activity Study of Paracetamol and Salicylic Acid

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Pharmacology & Pharmacy 2014年第13期5卷 1185-1191页

作者： Rosivaldo SBorges Taina G.Barros Glaecia A.N.Pereira Joao Batista jr Raimundo F.G.P.Beleza Filho Andrex A.S.Veiga Moises Hamoy Vanessa J.Mello Alberico B.Fda Silva carlos A.L.Barros Nucleo de Estudos e Selecao de Moleculas Bioativas Instituto de Ciencias da SaudeUniversidade Federal do ParaBelemBrazil Laboratorio de Farmacologia e Toxicologia de Produtos Naturais Instituto de Ciencias da SaudeUniversidade Federal do ParaBelemBrazil Instituto de Quimica de Sao carlos Universidade de Sao PauloSao CarlosBrazil

The paracetamol has more antioxidant properties than the salicylic acid on the several oxidative stress-forced models and one possible mechanism is due to electron or hydrogen transfer by the evaluated hydroxyl radicals. The antioxidant mechanism for the compounds studied here was performed by molecular modeling using quantum chemical calculations at the B3LYP level of theory. Our results show that the paracetamol has more antioxidant properties than the salicylic acid in experimental and theoretical studies. The theoretical mechanism show that the hydrogen transfer is more favorable than the electron transfer. From the study it was concluded that the electron abstraction for paracetamol is more favored than salicylic acid.

关键词： Paracetamol Salicylic Acid Phenol Derivatives NSAIDs Antioxidant

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Association between mucosal surface pattern under near focus technology and Helicobacter pylori infection

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World Journal of Gastrointestinal Endoscopy 2021年第10期13卷 518-528页

作者： Felipe Fiuza Fauze Maluf-Filho Edson Ide carlos Kiyoshi Furuya jr Sonia Nadia Fylyk Jennifer Nakamura Ruas Luciana Stabach Gabriela Albuquerque Araujo Sergio Eiji Matuguma Ricardo Sato Uemura Christiano Makoto Sakai Kendi Yamazaki Sergio Shiguetoshi Ueda Paulo Sakai Bruno Costa Martins Department of Endoscopy Hospital Alemão Oswaldo CruzSão Paulo 01323-020Brazil

BACKGROUND Many studies evaluated magnification endoscopy(ME)to correlate changes on the gastric mucosal surface with Helicobacter pylori(***)***,few studies validated these concepts with high-definition endoscopy without *** To access the association between mucosal surface pattern under near focus technology and *** infection status in a western *** Cross-sectional study including all patients referred to routine upper *** exams were performed using standard high definition(S-HD)followed by near focus(NF-HD)*** of erythema,erosion,atrophy,and nodularity were recorded during S-HD,and surface mucosal pattern was classified using NF-HD in the gastric *** were taken for rapid urease test and *** One hundred and eighty-seven patients were analyzed from August to November *** those,47(25.1%)were ***+,and 42(22.5%)had a previous *** *** the examination with S-HD,erythema had the best sensitivity for *** detection(80.9%).Exudate(99.3%),nodularity(97.1%),and atrophy(95.7%)demonstrated better specificity values,but with low sensitivity(6.4%-19.1%).On the other hand,the absence of erythema was strongly associated with ***-(negative predictive value=92%).With NF-HD,56.2%of patients presented type 1 pattern(regular arrangement of collecting venules,RAC),and only 5.7%of RAC+patients were ***+.The loss of RAC presented 87.2%sensitivity for *** detection,70.7%specificity,50%positive predictive value,and 94.3%negative predictive value,indicating that loss of RAC was suboptimal to confirm *** infection,but when RAC was seen,*** infection was *** The presence of RAC at the NF-HD exam and the absence of erythema at S-HD were highly predictive of *** negative *** the other hand,the loss of RAC had a suboptimal correlation with the presence of ***.

关键词： Diagnosis Endoscopy Gastric infection Gastritis Helicobacter pylori Sensitivity and specificity

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Total IgA and IgA reactivity to antigen I/II epitopes in HLA-DRB1*04 positive subjects

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Open Journal of Immunology 2013年第3期3卷 82-92页

作者： V. Wallace McCarlie James K. Hartsfield jr Janice S. Blum carlos González-Cabezas Judith R. Chin George J. Eckert Lorri A. Morford Mark D. Pescovitz Henry Rodriguez Margherita Fontana Richard L. Gregory Center for Oral Health Research Division of Orthodontics Department of Oral Health Science and Department of Microbiology Immunology and Molecular Genetics Colleges of Dentistry and Medicine University of Kentucky Lexington USA Center for Oral Health Research Division of Orthodontics Department of Oral Health Science College of Dentistry University of Kentucky Lexington USA Department of Biostatistics Schools of Medicine and Public Health Indiana University Indianapolis USA Department of Cariology Restorative Sciences and Endodontics School of Dentistry University of Michigan Ann Arbor USA Department of Microbiology and Immunology School of Medicine Indiana University Indianapolis USA Department of Pediatric Dentistry and Orthodontics School of Dental Medicine East Carolina University Greenville USA Department of Pediatric Dentistry School of Dentistry Indiana University Indianapolis USA Department of Pediatrics College of Medicine University of South Florida Tampa USA Departments of Oral Biology and Preventive and Community Dentistry and Department of Pathology and Laboratory Medicine Schools of Dentistry and Medicine Indiana University Indianapolis USA Departments of Surgery and Microbiology and Immunology School of Medicine Indiana University Indianapolis USA

Bacterial adherence to the acquired dental pellicle, important in dental caries (caries), is mediated by receptor-adhesins such as salivary agglutinin binding to Streptococcus mutans antigen I/II (I/II). Ten selected I/II epitopes were chosen to determine their reactivity to human salivary IgA. Previous studies suggested that a specific HLA biomarker group (HLA-DRB1*04) may have differential influence of immune responses to I/II. However, it was not known whether secretory IgA (SIgA) responses to the selected epitopes from HLA-DRB1*04 positive subjects were different compared to controls, or across other caries-related factors such as total IgA (TIgA). Thirty-two total subjects were matched according to HLA type, gender, ethnicity and age. HLA genotyping, oral bacterial, immunoglobulin and antibody analyses were performed. A large observed difference emerged with regard to the natural immune reservoir of TIgA in HLA-DRB1*04 positive subjects, specifically, a 27.6% reduction compared to controls. In contrast to all other epitopes studied, HLA-DRB1*04 positive subjects also exhibited reduced reactivity to I/II epitope 834-853. HLA-DRB1*04 positive subjects exhibited lower specific SIgA activity/TIgA to 834-853 and also a lower specific reactivity to 834-853/whole cell S. mutans UA159. Furthermore, HLA-DRB1*04 positive subjects exhibited lower responses to I/II in its entirety. The large observed difference in TIgA and the 834-853 reactivity pattern across multiple measures suggest potentially important connections pertaining to the link between HLA-DRB1*04 and caries.

关键词： Dental Caries Streptococcus mutans I/II IgA Immunomodulation Immunogenetics HLA-II DRB1 DRB1*04

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Fuzzy Online Auto-Tuning for an Industrial PID Controller

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Journal of Energy and Power Engineering 2014年第7期8卷 1272-1278页

作者： Alain Segundo Potts Basilio Thome de Freitas jr. Jose carlos Amaro Center of Engineering Modeling and Applied Social Sciences Federal University of ABC Santo Andre 09210-580 Brazil Sollwert lndustria e Comercio LTDA Sao Paulo 0438-230 Brazil

This paper presents a fuzzy tuning system for real-time industrial PID (proportional-integral-derivative) controllers. The algorithm set the proportional gain, integral time and derivative time of a classical PID structure according to the set point, error and error derivative of the process, respectively. The tuning of the PID controller is based on a fuzzy inference machine. The set of rules of the fuzzy inference machine was obtained by experts engineering. The system is tested in an austempering process but can be applied in any industrial plant. Besides, an analysis between the response of the process with a PID controller and the system of fuzzy auto-tuning for PID proposed was made.

关键词： PID控制器模糊推理机工业厂房在线自整定调节系统比例增益积分时间模糊自整定

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