1,322 research outputs found

    A Procedure to Calibrate a Multi-Modular Telescope

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    A procedure has been developed for the charge, mass and energy calibration of ions produced in nuclear heavy ion reactions. The charge and mass identification are based on a Δ\DeltaE-E technique. A computer code determines the conversion from ADC channels into energy values, atomic number and mass of the detected fragments by comparing with energy loss calculations through a minimization routine. The procedure does not need prior measurements with beams of known energy and charge. An application of this technique to the calibration of the MULTICS apparatus is described.Comment: 9 pages, Tex file, 3 postscript figures available upon request from [email protected]; to appear in Nucl. Inst. Met

    Dependence of Variational Perturbation Expansions on Strong-Coupling Behavior. Inapplicability of delta-Expansion to Field Theory

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    We show that in applications of variational theory to quantum field theory it is essential to account for the correct Wegner exponent omega governing the approach to the strong-coupling, or scaling limit. Otherwise the procedure either does not converge at all or to the wrong limit. This invalidates all papers applying the so-called delta-expansion to quantum field theory.Comment: Author Information under http://www.physik.fu-berlin.de/~kleinert/institution.html . Latest update of paper (including all PS fonts) at http://www.physik.fu-berlin.de/~kleinert/34

    In Vitro Activity Of Artemisia Annua L (asteraceae) Extracts Against Rhipicephalus (boophilus) Microplus [atividade In Vitro De Extratos De Artemisia Annua L (asteraceae) Sobre Rhipicephalus (boophilus) Microplus]

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    The activity of plant extracts on parasites may indicate groups of substances that are potentially useful for controlling Rhipicephalus (Boophilus) microplus. The aim of the present study was to investigate the in vitro action of Artemisia annua extracts on this tick. The concentrations of the sesquiterpene lactones artemisinin and deoxyartemisinin present in plant extracts were quantified via high-performance liquid chromatography. Four extracts produced from the concentrated crude extract (CCE) were evaluated on larvae using the impregnated paper method, with readings after 24 hours of incubation. The engorged females were immersed in the CCE and in its four derived extracts for five minutes, with incubation for subsequent analysis of biological parameters. The extracts were not effective on the larvae at the concentrations tested (3.1 to 50 mg.mL-1). The CCE showed greater efficacy on engorged females (EC50 of 130.6 mg.mL-1 and EC90 of 302.9 mg.mL-1) than did the derived extracts. These results tend to confirm that the action of artemisinin on engorged females of R. (B.) microplus is conditional to their blood intake. In this case, in vitro methods would be inadequate for effective evaluation of the action of A. annua on R. (B.) microplus.2013135Amaral, N.K., Guidelines for the evaluation of ixodicides against the cattle tick Boophilus microplus (Canestrini, 1887) (Acari: Ixodidae) (1993) Revista Brasileira De Parasitologia Veterinária, 2 (2), pp. 144-151(2009) Anuário Da Pecuária Brasileira, p. 360. , ANUALPEC, Sao Paulo: Angra FNP PesquisasBorges, L.M.F., Acao do extrato hexanico de frutos maduros de Melia azedarach (Meliaceae) sobre Boophilus microplus (Acari: Ixodidae) em bezerros infestados artificialmente (2005) Revista De Patologia Tropical, 34 (1), pp. 53-59Cala, A.C., (2010) Avaliação Da Atividade De Artemisia Annua L., Melia Azedarach L. E Trichilia Claussenii C. Sobre Nematódeos Gastrintestinais De Ovinos, p. 64. , Dissertacao (Mestrado)- Universidade Estadual Paulista, Faculdade de Ciencias Agrarias e Veterinarias, JaboticabalCeleghini, R.M.S., Desenvolvimento e validacao de metodologia analitica por CLAE-IR para determinacao de artemisinina em Artemisia annua L (2009) Química Nova, 32 (4), pp. 875-878Chagas, A.C.S., Efeito acaricida de oleos essenciais e concentrados emulsionaveis de Eucalyptus em Boophilus microplus (2002) Brazilian Journal of Veterinary Research and Animal Science, 39 (5), pp. 247-253Chagas, A.C.S., Sensibilidade do carrapato Boophilus microplus a solventes (2003) Ciência Rural, 33 (1), pp. 109-114Creek, D.J., Kinetics of ironmediated artemisinin degradation:Effect of solvent composition and iron salt (2005) Journal of Pharmaceutical Sciences, 94 (8), pp. 1820-1829Drummond, R.O., Boophilus annulatus and B. Microplus: Laboratory tests of insecticides (1973) Journal of Economic Entomology, 66 (1), pp. 130-133Ekanem, A.P., Brisibe, E.A., Effects of ethanol extract of Artemisia annua L. Against monogenean parasites of Heterobranchus longifilis (2010) Parasitology Research, 106 (5), pp. 1135-1139Fernandes, F.F., Freitas, E.P.S., Acaricidal activity of an oleoresinous extract from Copaifera reticulata (Leguminosae: Caesalpinioideae against larvae of the southern cattle tick, Riphicephalus (Boophilus) microplus (Acari:Ixodidae) (2007) Veterinary Parasitology, 147 (1-2), pp. 150-154Ferreira, J.F.S., Agrotechnological aspects of the anti-malarial plant Artemisia annua and its potential use in animal health in Appalachia (2006) International Symposium on Perfume, Aromatic and Medicinal Plants, (2-4), pp. 797-804. , Revue de Regions Arides - Numero special - Actes du seminaire international les Plants a Parfum, Aromatiques et Medicinales (English version: International Center for Agricultural Research in Dry AreasFerreira, J.F.S., Nutrient Deficiency in the Production of Artemisinin, Dihydroartemisinic Acid, and Artemisinic Acid in Artemisia annua L (2007) Journal of Agricultural and Food Chemistry, 55 (5), pp. 1686-1694Ferreira, J.F.S., Gonzalez, J.M., Chemical and biological stability of artemisinin in bovine rumen fluid and its kinetics in goats (Capra hircus) (2008) Revista Brasileira De Parasitologia Veterinária, 17 (SUPPL. 1), pp. 103-109Furlong, J., O carrapato dos bovinos e a resistencia: Temos o que comemorar? (2007) A Hora Veterinária, 159, pp. 26-32Grisi, L., Impacto economico das principais ectoparasitoses em bovinos no Brasil (2002) A Hora Veterinária, 21 (125), pp. 8-10Heimerdinger, A., Extrato alcoolico de Capim-cidreira (Cymbopogon citratus) no controle do Boophilus microplus em bovinos (2006) Revista Brasileira De Parasitologia Veterinária, 15 (1), pp. 37-39Idris, U.A., Adam, S.E., Tartour, G., The anthelmintic efficacy of Artemisia herba-alba against Haemonchus contortus infection in goats (1982) Animal Health Quarterly, 22 (3), pp. 138-143Iqbal, Z., Anthelmintic activity of Artemisia brevifolia in sheep (2004) Journal of Ethnopharmacology, 93 (2), pp. 265-268Keiser, J., Artesunate and artemether are effective fasciolicides in the rat model and in vitro (2006) Journal of Antimicrobial Chemotherapy, 57 (6), pp. 1139-1145Keiser, J., Efficacy and safety of artemether against a natural Fasciola hepatica infection in sheep (2008) Parasitology Research, 103 (3), pp. 517-522Keiser, J., Utzinger, J., Food-borne trematodiasis: Current chemotherapy and advances with artemisinins and synthetic trioxolanes (2007) Trends In Parasitology, 23 (11), pp. 555-562Klayman, D.L., Qinghaosu (Artemisinin): Na antimalarial drug from China (1985) Science, 228 (4703), pp. 1049-1055La-Scalea, M.A., Silva, H.S.R.C., Ferreira, E., Reducao voltametrica de artemisinina e sua interacao com grupo heme (hemina) (2007) Brazilian Journal of Pharmaceutical Sciences, 43 (3), pp. 371-383Martins, R.M., Estudio in vitro de la accion acaricida del aceite esencial de la graminea Citronela de Java (Cymbopogon winterianus Jowitt) en la garrapata Boophilus microplus (2006) Revista Brasileira De Plantas Medicinais De Botucatu, 8 (2), pp. 71-78Meshnick, S.R., Second-generation antimamalarial endoperoxides (1996) Parasitology Today, 12 (2), pp. 79-82Ribeiro, V.L.S., Acaricidal properties of extracts from the aerial parts of Hypericum polyanthemum on the cattle tick Boophilus microplus (2007) Veterinary Parasitology, 147 (1-2), pp. 199-203Rodrigues, R.A.F., Otimizacao do processo de extracao e isolamento do antimalarico artemisinina a partir de Artemisia annua L (2006) Química Nova, 29 (2), pp. 368-372Silva, H.S.R.C., (2006) Antimaláricos Potenciais: Pró-fármacos Poliméricos E Formas De Liberação Controlada De Artemisinina, p. 209. , Tese (Doutorado)-Universidade de Sao Paulo, Sao PauloSimoes, C.M., (2004) Farmacognosia: Da Planta Ao Medicamento, p. 1102. , 5. ed. Porto Alegre: Editora da UFRGSFlorianopolis: Editora da UFSCTaranto, A.G., Estudo sobre o mecanismo de acao da artemisinina e dos endoperoxidos, a mais nova classe de agents antimalaricos (2006) Sitientibus, 34, pp. 47-58Tariq, K.A., Anthelmintic activity of extracts of Artemisia absinthium against ovine nematodes (2009) Veterinary Parasitology, 160 (1-2), pp. 83-8

    Isotopic composition of fragments in multifragmentation of very large nuclear systems: effects of the chemical equilibrium

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    Studies on the isospin of fragments resulting from the disassembly of highly excited large thermal-like nuclear emitting sources, formed in the ^{197}Au + ^{197}Au reaction at 35 MeV/nucleon beam energy, are presented. Two different decay systems (the quasiprojectile formed in midperipheral reactions and the unique source coming from the incomplete fusion of projectile and target in the most central collisions) were considered; these emitting sources have the same initial N/Z ratio and excitation energy (E^* ~= 5--6 MeV/nucleon), but different size. Their charge yields and isotopic content of the fragments show different distributions. It is observed that the neutron content of intermediate mass fragments increases with the size of the source. These evidences are consistent with chemical equilibrium reached in the systems. This fact is confirmed by the analysis with the statistical multifragmentation model.Comment: 9 pages, 4 ps figure

    Multicriteria power engineering problems and fuzzy set based methods of their solution

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    The results of research into the use of models and methods of multicriteria decision making in a fuzzy environment for solving power engineering problems are presented. Two general classes of models related to multiobjective ( models) and multiattribute ( models) problems as well as methods of their analysis based on the application of the Bellman-Zadeh approach to decision making in a fuzzy environment and techniques of fuzzy preference modeling, respectively, are briefly considered. A review of the authors’ results associated with the application of these models and methods for solving diverse types of problems of power system and subsystems planning, operation, and control is presented. The recent results on the use of and models and methods of their analysis for the allocation of reactive power sources in distribution systems and for the prioritization in maintenance planning in distribution systems, respectively, are considered.Наведено результати щодо досліджень використання моделей та методів багатокритеріального прийняття рішень в нечіткому середовищі при розв'язанні задач електроенергетичного спрямування. Розглянуто два класи моделей, які належать до багатоцільових ( модель) та багатоатрибутних ( модель) задач, а також методи їхнього аналізу, що засновані як на використанні підхода Беллмана-Заде до прийняття рішень у нечіткому середовищі, так і на техніці, пов'язаній з визначенням нечітких переваг. Представлено огляд результатів, які отримано авторами при використанні вказаних моделей та методів для вирішення задач проектування та управління роботою енергетичних систем і підсистем. Останні результати, пов'язані з використанням і моделей та методів їхнього аналізу, належать до задач роз- поділу джерел реактивної потужності у розподільних мережах та визначення пріоритетів при плануванні їхнього обслуговування.Представлены результаты исследований по использованию моделей и методов многокритериального принятия решений в нечеткой среде при решении задач электроэнергетического характера. При этом рассматривается два класса моделей, относящихся к многоцелевым (модель) и многоатрибутным (модель) задачам, а также методы их анализа, основанные как на использовании подхода Беллмана-Заде к принятию решений в нечеткой среде, так и технике, связанной с определением нечетких предпочтений. Представлен обзор результатов, полученных авторами при использовании указанных моделей и методов для решения различных задач, связанных с проектированием и управлением работой энергетических систем и подсистем. Последние результаты, связанные с применением и моделей и методов их анализа, относятся к задачам распределения источников реактивной мощности в распределительных сетях и определения приоритетов при планировании их обслуживания

    Asymptotically Improved Convergence of Optimized Perturbation Theory in the Bose-Einstein Condensation Problem

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    We investigate the convergence properties of optimized perturbation theory, or linear δ\delta expansion (LDE), within the context of finite temperature phase transitions. Our results prove the reliability of these methods, recently employed in the determination of the critical temperature T_c for a system of weakly interacting homogeneous dilute Bose gas. We carry out the explicit LDE optimized calculations and also the infrared analysis of the relevant quantities involved in the determination of TcT_c in the large-N limit, when the relevant effective static action describing the system is extended to O(N) symmetry. Then, using an efficient resummation method, we show how the LDE can exactly reproduce the known large-N result for TcT_c already at the first non-trivial order. Next, we consider the finite N=2 case where, using similar resummation techniques, we improve the analytical results for the nonperturbative terms involved in the expression for the critical temperature allowing comparison with recent Monte Carlo estimates of them. To illustrate the method we have considered a simple geometric series showing how the procedure as a whole works consistently in a general case.Comment: 38 pages, 3 eps figures, Revtex4. Final version in press Phys. Rev.

    Fragment Isospin as a Probe of Heavy-Ion Collisions

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    Isotope ratios of fragments produced at mid-rapidity in peripheral and central collisions of 114Cd ions with 92Mo and 98Mo target nuclei at E/A = 50 MeV are compared. Neutron-rich isotopes are preferentially produced in central collisions as compared to peripheral collisions. The influence of the size (A), density, N/Z, E*/A, and Eflow/A of the emitting source on the measured isotope ratios was explored by comparison with a statistical model (SMM). The mid-rapidity region associated with peripheral collisions does not appear to be neutron-enriched relative to central collisions.Comment: 12 pages including figure

    Fragment Production in Non-central Collisions of Intermediate Energy Heavy Ions

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    The defining characteristics of fragment emission resulting from the non-central collision of 114Cd ions with 92Mo target nuclei at E/A = 50 MeV are presented. Charge correlations and average relative velocities for mid-velocity fragment emission exhibit significant differences when compared to standard statistical decay. These differences associated with similar velocity dissipation are indicative of the influence of the entrance channel dynamics on the fragment production process

    Root diseases of wheat in Minas Gerais and Distrito Federal

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    Este trabalho mostra a ocorrência da podridão comum de raízes de trigo (Triticum aestivum L.) em algumas regiões do Cerrado do Brasil Central, no Estado de Minas Gerais e no Distrito Federal. O principal organismo isolado das raízes infectadas foi o fungo Cochliobolus sativus. A incidência e a intensidade da podridão comum foram baixas nas lavouras de trigo não-irrigado de Minas Gerais, apesar do elevado número de esporos de C. sativus encontrados na maior parte delas. Nas lavouras de trigo irrigado do Distrito Federal, entretanto, populações menores desse organismo foram responsáveis por infecções mais elevadas. As maiores concentrações de esporos de C. sativus nos solos amostrados estavam localizadas na camada superficial, de 0-3 cm de profundidade.This work reports the occurrence of common root rot of wheat (Triticum aestivum L.) in some regions of the "cerrado" of Central Brazil, in the states of Minas Gerais and Distrito Federal. Cochliobolus sativus was the main organism isolated from rotted roots. The incidence and intensity of common root rot were low in the non-irrigated wheat fields from Minas Gerais, in spite of the high spore populations of C. sativus found in most soils. The irrigated wheat fields from Distrito Federal, however, had a higher incidence and intensity of the disease with much lower spore populations. The highest concentration of spores in the sampled soils was found in the surface layer of 0-3 cm

    Nutritional Evaluation Of Children With Chronic Cholestatic Disease

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    Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)To evaluate the nutritional status of children with persistent cholestasis and to compare the anthropometric indices between children with and without liver cirrhosis and children with and without jaundice. Methods Children with persistent cholestasis, i.e. increased direct bilirrubin or changes in the canalicular enzyme gamma-glutamyl transferase (GGT), were included. The anthropometric measures were weight (W), height or length (H), arm circumference (AC), triceps skinfold thickness (TST), arm muscle circumference (AMC), and body mass index (BMI). Results Ninety-one children with cholestasis, with current median age of 12 months, were evaluated. W/age (A) and H/A indices below -2 Z-scores were observed in 33% and 30.8% of patients, respectively. Concerning the W/H index and BMI, only 12% and 16% of patients, respectively, were below -2 Z-scores. Regarding AC, 43.8% of 89 evaluated patients had some depletion. Observing the TST, 64% of patients had depletion, and 71.1% of the 45 evaluated patients had some degree of depletion regarding the ACM index. Conclusion Evaluation using weight in patients with chronic liver diseases may overestimate the nutritional status due to visceromegaly, subclinical edema, or ascites. Indices that correlate weight and height, such as W/H and BMI, may also not show depletion because of the chronic condition in which there are depletion of both weight and height. TST, AC, and ACM are parameters that better estimate nutritional status and should be part of the management of patients with liver diseases and cholestasis. © 2015 Sociedade Brasileira de Pediatria.922197205CNPq, Conselho Nacional de Desenvolvimento Científico e TecnológicoConselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq
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