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International Journal of Mining Science and Technology 2012年第5期22卷 711-718页

作者： Denis l.Guerra Silze P.Oliveira ricardo A.R.Silva Victor leidens Adriano C.Batista Federal University of Mato Grosso DRM-ICET-UFMTCuiabá 78060900Brazil Universidade Estadual do Norte Fluminense Rio de Janeiro 2801302Brazil

In this study,the original tourmaline and beryl mineral samples have been collected from a Brazilian *** objective of this study was to examine the adsorption behavior of Brazilian ciclosilicate samples,towards divalent metals(Pb 2+,Mn 2+,and Zn 2+) in ethanol solution has been studies by a batch *** ciclosilicate samples were characterized by elemental analysis,Fourier transform infrared spectroscopy,helium picnometry,mercury porosity,and nitrogen *** langmuir expression for adsorption isotherm was applied in order to determine the adsorption capacity to form a monolayer and the constant related to the adsorption *** aqueous solution there was a significant adsorption increase with the temperature and pronounced synergistic effects were *** maximum number of moles adsorbed was determined to be 12.48 and 11.49 mmol/g for systems Pb 2+ /beryl and Pb 2+ /tourmaline,*** energetic effects caused by metal cations adsorption were determined through calorimetric *** indicated the existence of favorable conditions for such Pb 2+-,Mn 2+-,and Zn 2+-OH interactions.

关键词： Industrial minerals Environmental Pollution Surface modification Wasteprocesing

Modeling egg development of the pest Clavipalpus ursinus （Coleoptera： Melolonthidae） using a temperature-dependent approach

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Insect Science 2012年第6期19卷 657-665页

作者： Andrea Escobar Rodrigo Gil Carlos ricardo Bojaca Jaime Jimenez Facultad de Ciencias Naturales e Ingenieria Departamento de Ciencias Basicas Universidad de Bogota Jorge Tadeo Lozano Bogota Direccion Tecnica de Sanidad Vegetal Instituto Colombiano Agropecuario Bogota Colombia

Predicting the population dynamics of insects in natural conditions is es- sential for their management or preservation, and temperature-dependent development models contribute to achieving this. In this research the effects of temperature and soil moisture content on egg development and hatching of Clavipalpus ursinus （Blanchard） were evaluated. The eggs were exposed to seven temperature treatments with averages of 7.2, 13.0, 15.5, 19.7, 20.6, 22.0 and 25.3~C, in combination with three soil moisture contents of 40%, 60% and 80%. A linear and two non-linear （lactin and Briere） models were evaluated in order to determine the thermal requirements of this developmental stage. Temperature affected significantly the time of development and egg hatching, while no significant effect was observed for moisture content. Thermal requirements were set as： 7.2℃ for lower developmental threshold, 20.6℃ for optimum developmental threshold, 25.3℃ for maximum temperature and 344.83 degree-days for the thermal constant. The linear model described satisfactorily egg development at intermediate temperatures; nev- ertheless, a slightly better fit of the observed data was obtained with the lactin model. Egg development took place inside a narrow range of temperatures. Consequently, an increment of soil temperature could generate a negative impact on the population size of this species or changes in its biological parameters.

关键词： egg development pests soil moisture thermal requirements

Entrepreneurship and Unemployment Cycles： A Delay Differential Equation Approach

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Frontiers of Economics in China-Selected Publications from Chinese Universities 2013年第2期8卷 288-292页

作者： Joao ricardo Faria MPA Program University of Texas at E1 Paso E1 Paso TX 79968-0703 USA

This paper is an application of delay differential equations to entrepreneurship and unemployment. It shows that the results of empirical studies can be replicated through a simple DDE. The paper also carries out a comparative study between a solution of a DDE and the observation of cyclic behaviors. The calculated delay （and growth rate） of the entrepreneurship DDE for the US and Spain is 1.25 years （1.25）, for Ireland is 1.75 years （0.89）, and for the UK is 2 years （0.78）. The delay （and growth rate） of the unemployment DDE for the US and Ireland is 1.5 years （1.04）, for Spain is 2 years （0.78）, and for the UK is 2.5 years （0.62）.

关键词： new firms employment creation cycles delay differential equations

Induced pluripotent stem cells from Huntington's disease patients:a promising approach to define and correct disease-related alterations

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Neural Regeneration Research 2019年第5期14卷 769-770页

作者： Azra Fatima ricardo Gutiérrez-Garcia David Vilchez Institute for Genetics and Cologne Excellence Cluster for Cellular Stress Responses in Aging-Associated Diseases(CECAD) University of Cologne

Adult somatic cells such as skin or blood cells from either health donors or patients can be reprogrammed into induced pluripotent stem cells(iPSCs).Given their unlimited self-renewal and differentiation capacities,iPSCs are an invaluable resource to generate terminally differentiated ***,iPSCs can facilitate the study of human diseases and drug screening,holding great promise for regenerative *** significant advantage of iPSC disease-modeling is that normal and mutant proteins are expressed at endogenous *** addition,subtle phenotypes and the effects of genetic background variations can be assessed by comparison between iPSC lines obtained from different patients and healthy donors as well as isogenic lines,in which disease-related mutations are corrected.

关键词： Adult somatic cells skin or blood cells Huntington’s disease patients

Outcome of varicocele repair in men with nonobstructive azoospermia： systematic review and meta-analysis

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Asian Journal of Andrology 2016年第2期18卷 246-253,J0005,J0006页

作者： Sandro C Esteves ricardo Miyaoka Matheus Roque Ashok Agarwal ANDROFERT Center for Male Reproduction Av. Dr. Heitor Penteado 1464 Campinas SP 13075-460 Brazil ORlGEN Center for Reproductive MedicineRio de Janeiro Aw Rodolfo de Amoedo 140 Rio de Janeiro RJ 22620-330 Brazil American Center for Reproductive Medicine 10681. Carnegie Avenue X-11Cleveland OH 44195 USA.

The objective of this systemic review was to evaluate the benefit of repairing clinical varicocele in infertile men with nonobstructive azoospermia （NOA）. The surgically obtained sperm retrieval rate （SRR） and pregnancy rates following assisted reproductive technology （ART） with the use of retrieved testicular sperm were the primary outcomes. The secondary outcomes included the presence of viable sperm in postoperative ejaculate to avoid the testicular sperm retrieval and pregnancy rates （both assisted and unassisted） using postoperative ejaculated sperm. An electronic search to collect the data was performed using the MEDlINE and EMBASE databases until April 2015. Eighteen studies were included in this systematic review and accounted for 468 patients who were diagnosed with NOA and varicocele. These patients were subjected to either surgical varicocele repair or percutaneous embolization. Three controlled studies evaluating sperm retrieval outcomes indicated that in patients who underwent varicocelectomy, SRR increased compared to those without varicocele repair （OR： 2,65; 95% Cl. 1.69-4.14; P 〈 0.001）. Although pregnancy rates with the use of testicular sperm favored the varicocelectomy group, results were not statistically significant （clinical pregnancy rate OR： 2.07; 95% CI： 0.92-4.65; P = 0.08; live birth rate OR： 2.19; 95% CI： 0.99-4.83; P = 0.05）. The remaining fifteen studies reported postoperative semen analysis results. In 43.9% of the patients （range： 20.8%-55.0%）, sperm were found in postoperative ejaculates. Pregnancy rates for unassisted and assisted （after IVF/ICSI） were 13.6% and 18.9% in the group of men with sperm in postoperative ejaculates, respectively. Our findings indicate that varicocelectomy in patients with NOA and clinical varicocele is associated with improved SRR. In addition, approximately 44% of the treated men will have enough sperm in the ejaculate to avoid sperm retrieval. limited data on pregnancy outcomes with both postoperative

关键词： azoospermia male infertility meta-analysis sperm retrieval systematic review varicocele varicocelectomy

Esophagus and regenerative medicine

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World Journal of Gastroenterology 2012年第47期18卷 6894-6899页

作者： ricardo londono Blair A Jobe Toshitaka Hoppo Stephen F Badylak McGowan Institute for Regenerative Medicine PittsburghPA 15219United States School of Medicine University of PittsburghPittsburghPA 15261United States Department of Cardiothoracic Surgery University of PittsburghPittsburghPA 15232United States Department of Surgery University of PittsburghPittsburghPA 15213United States Department of Bioengineering University of PittsburghPittsburghPA 15219United States

In addition to squamous cell carcinoma,the incidence of Barrett's esophagus with high-grade dysplasia and esophageal adenocarcinoma is rapidly increasing ***,the current standard of care for esophageal pathology involves resection of the affected tissue,sometimes involving radical *** exception,these procedures are associated with a high morbidity,compromised quality of life,and unacceptable mortality *** medicine approaches to functional tissue replacement include the use of biological and synthetic scaffolds to promote tissue remodeling and *** the case of esophageal repair,extracellular matrix(ECM) scaffolds have proven to be effective for the reconstruction of small patch defects,anastomosis reinforcement,and the prevention of stricture formation after endomucosal resection(EMR).More so,esophageal cancer patients treated with ECM scaffolds have shown complete restoration of a normal,functional,and disease-free epithelium after *** studies provide evidence that a regenerative medicine approach may enable aggressive resection of neoplastic tissue without the need for radical esophagectomy and its associated complications.

关键词： Esophageal repair Biomaterial mediated esophageal repair Extracellular matrix Extracellular matrix scaffold

Spectrum of anemia associated with chronic liver disease

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World Journal of Gastroenterology 2009年第37期15卷 4653-4658页

作者： Rosario Gonzalez-Casas E Anthony Jones ricardo Moreno-Otero Digestive Disease Service and Center for Investigation of Hepatic and Digestive Diseases University Hospital La Princesa Autonomous University of Madrid Madrid 28006 Spain

Anemia of diverse etiology is a common complication of chronic liver diseases. The causes of anemia include acute or chronic gastrointestinal hemorrhage, and hypersplenism secondary to portal hypertension. Severe hepatocellular disease predisposes to hemorrhage because of impaired blood coagulation caused by deficiency of blood coagulation factors synthesized by hepatocytes, and/or thrombocytopenia. Aplastic anemia, which is characterized by pancytopenia and hypocellular bone marrow, may follow the development of hepatitis. Its presentation includes progressive anemia and hemorrhagic manifestations. Hematological complications of combination therapy for chronic viral hepatitis include clinically signif icant anemia, secondary to treatment with ribavirin and/or interferon. Ribavirininduced hemolysis can be reversed by reducing the dose of the drug or discontinuing it altogether. Interferons may contribute to anemia by inducing bone marrow suppression. Alcohol ingestion is implicated in the pathogenesis of chronic liver disease and may contribute to associated anemia. In patients with chronic liver disease, anemia may be exacerbated by defi ciency of folic acid and/or vitamin B12 that can occur secondary to inadequate dietary intake or malabsorption.

关键词： Anemia liver disease liver failure Aplastic anemia Pegylated interferon Ribavirin Alcohol

Size Structure and Biomass of the Panama Grunt (Pomadasys panamensis) from Bycatch inthe Southeastern Gulf of California

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Open Journal of Marine Science 2012年第1期2卷 1-7页

作者： José alberto Rodríguez-Preciado Juan Madrid-Vera ricardo Meraz-Sánchez 不详

A population analysis was made using data of the grunt Pomadasys panamensis. The information is from the catch from 260 hauls in estuarine waters, open-ocean waters, and off the coast of Sinaloa and northern Nayarit, Mexico, in the southeastern Gulf of California. The area of influence is about 120,000 km2 and includes about a third of the drag area of the largest shrimp fleet of the American Pacific. The average length in the population was 210 mm. The maximum length was 430 mm and the minimum was 50 mm. The analysis for the frequency distributions of the lengths and the multinomial solution produced representative modal groups for 160 mm, 190 mm, and 230 mm. The simulation of the biomass density gave an estimate close to 90 t, with 650,000 organisms before starting the fishing season in the region. The density was 0.19 kg ha–1. The colonization was 0.42% or 42 %. The model was validated using the Aikaikae criterion (AIC). The results provide an overview of the initial biomass densities and population structure of the species caught as bycatch, demonstrating the importance of this species abundance in the shrimp fishery, and generating a source of monetary income to the crew of the fishing fleet. The persistence of the species to fishing provides an example to study the mechanisms of survival.

关键词： Colonization Multinomial Solution Model Pomadasys panamensis Aikaikae

Technological insights:combined impedance manometry for esophageal motility testing-current results and further implications

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World Journal of Gastroenterology 2006年第39期12卷 6266-6273页

作者： Huan Nam Nguyen Gerson ricardo Souza Domingues Frank lammert Department of Internal Medicine University of Technology RWTH-Aachen Germany Department of Internal Medicine Gama Filho Unisverity Rio de Janeiro Brazil Department of Internal Medicine University of Bonn Germany

This review focuses on current aspects of the novel technology of combined impedance manometry for esophageal motility testing. It presents methodological features, summarizes current results and discusses implications for further research. The combined technique assesses simultaneously bolus transport and associated peristalsis, thus allowing detailed analysis of the relationships between bolus transit and esophageal motility. Recent studies demonstrate that combined impedance manometry provides important additional information about esophageal motility as compared to conventional manometry: (1) monitoring of bolus transport patterns, (2) calculation of bolus transit parameters, (3) evaluation of bolus clearance, (4) monitoring of swallow associated events such as air movement and reflux, and (5) investigation of the relationships between bolus transit and lES relaxation. Studies with healthy subjects have identified several useful parameters for comprehensive assessment of eosphageal function. These parameters were found to be pathological in patients with classical achalasia, mild GERD, and ineffective esophageal motility. The technology of combined impedance manometry provides an important new tool for esophageal function testing, advancing both clinical and basic research. However, several important issues remain to be standardized to make the technique suitable for widely clinical use.

关键词： Combined impedance manometry Esophageal function testing Review

Distributed representations of atoms and materials for machine learning

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npj Computational Materials 2022年第1期8卷 415-423页

作者： luis M.Antunes ricardo Grau-Crespo Keith T.Butler Department of Chemistry University of ReadingWhiteknightsReadingRG66DXUK SciMl Scientific Computing DepartmentRutherford Appleton LaboratoryHarwellOX110QXUK

The use of machine learning is becoming increasingly common in computational materials *** build effective models of the chemistry of materials,useful machine-based representations of atoms and their compounds are *** derive distributed representations of compounds from their chemical formulas only,via pooling operations of distributed representations of *** compound representations are evaluated on ten different tasks,such as the prediction of formation energy and band gap,and are found to be competitive with existing benchmarks that make use of structure,and even superior in cases where only composition is ***,we introduce an approach for learning distributed representations of atoms,named SkipAtom,which makes use of the growing information in materials structure databases.

关键词： representations operations competitive