172 research outputs found
Oral mucositis in pediatric acute lymphoblastic leukemia patients: evaluation of microbiological and hematological factors
To investigate the associations of oral microbiota, leucocytes count, neutrophil count, platelet counts and hemoglobin level, and the severity of oral mucositis in pediatric patients with acute lymphoblastic leukemia (ALL) receiving chemotherapy. 71 prospective patients were included. Analyses of oral microbiota and blood sample were conducted on days 14 (D14) and 56 (D56) of the Brazilian GBTLI-99 treatment protocol. Herpes simplex virus (HSV) identification was performed by PCR followed by DNA sequencing analysis. Bacteria and fungi identification was obtained by standard microbiological culture tests. 103 episodes of mucositis occurred, being 65 at D14 and 38 at D56. Most cases positive for herpes viral DNA sequences were identified as HSV-1. At D14, we found a significant association between the severity of mucositis and presence of HSV-1 (p = 0.0347), Candida spp. (p = 0.0078), and low platelet count (p = 0.0064). At D56, we found a significant association between the severity of mucositis and the presence of HSV-1 (p = 0.0317), previous HSV-1 presence on D14 (p < 0.0001) and neutrophil count (p = 0.0211). Clinical relevance: the identification of risk factors for mucositis in children and adolescents may contribute to the development of new strategies for prevention and/or treatment, reducing the complications associated with this condition. The presence of HSV, platelet count, and Candida spp. presence at D14 of ALL induction treatment is associated with increased severity of mucositis in children and adolescents. At D56 of ALL treatment, mucositis severity was associated with neutrophil count, HSV presence, and previous presence of HSV (at D14).325322330FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPES
Solar Neutrinos Before and After KamLAND
We use the recently reported KamLAND measurements on oscillations of reactor
anti-neutrinos, together with the data of previously reported solar neutrino
experiments, to show that: (1) the total 8B neutrino flux emitted by the Sun is
1.00(1.0 \pm 0.06) of the standard solar model (BP00) predicted flux, (2) the
KamLAND measurements reduce the area of the globally allowed oscillation
regions that must be explored in model fitting by six orders of magnitude in
the Delta m^2-tan^2 theta plane, (3) LMA is now the unique oscillation solution
to a CL of 4.7sigma, (4) maximal mixing is disfavored at 3.1 sigma, (5)
active-sterile admixtures are constrained to sin^2 eta<0.13 at 1 sigma, (6) the
observed ^8B flux that is in the form of sterile neutrinos is
0.00^{+0.09}_{-0.00} (1 sigma), of the standard solar model (BP00) predicted
flux, and (7) non-standard solar models that were invented to completely avoid
solar neutrino oscillations are excluded by KamLAND plus solar at 7.9 sigma .
We also refine quantitative predictions for future 7Be and p-p solar neutrino
experiments.Comment: Published version, includes editorial improvement
ADSORÇÃO DO CORANTE TÊXTIL AZUL REMAZOL POR PECÍOLO DE BURITI (Mauritia flexuosa L.f.)
No presente trabalho foi investigada a remoção do corante azul remazol usando como adsorvente o pecíolo do buriti. A partir do espectro de infravermelho, foram identificados os principais grupos funcionais do adsorvente. O comprimento de onda de máxima absorção (λmáx) do corante foi obtido por espectrofotometria na região do UV-visível foi 595nm. O pH no ponto de carga zero do adsorvente foi estimado graficamente em torno de 4,6. Foram investigados alguns parâmetros tais como: a influência do pH, o tempo de contato e a concentração do corante. A capacidade de adsorção do corante é maior em pH's mais baixos. Os modelos cinéticos de adsorção que apresentaram os melhores ajustes foram os de pseudossegunda ordem para a menor concentração (R2 ≈ 93%) e Elovich para as concentrações de 400 e 800 mg.L-1 (R2 ≈ 97%). Os modelos isotérmicos utilizados foram os de Freundlich, Sips e Multicamada. Os modelos de Sips e Multicamada foram os que ajustaram melhor os dados de equilíbrio (R2 > 96%). A quantidade máxima adsorvida estimada pelo modelo de Sips foi 33 mg.g-1. Essa capacidade de adsorção relativamente alta torna o pecíolo do buriti um adsorvente com potencial para remover corantes.Palavras-chave: Pecíolo de buriti (Mauritia flexuosa L.f.). Adsorção. Corantes têxteis.ADSORPTION OF BLUE TEXTILE DYE REMAZOL FOR BURITI PETIOLE (Mauritia flexuosa Lf)Abstract: In the present study was investigated the removal of Remazol Blue dye using as adsorbent buriti petiole. From the IR spectrum. the main functional groups of the adsorbent were identified. The wavelength of maximum absorption (λmáx) of the dye was obtained by spectrophotometric in the UV-visible was 595 nm. The pH at the point of zero charge of the adsorbent was estimated graphically at 4,6. Were investigated Some parameters were investigated such as: the influence of pH, the contact time and the concentration of the dye. The adsorption capacity of the dye is higher in lower pH's. The adsorption kinetic models that showed the best fits were the pseudo-second order for the lower concentration (R2 ≈ 93%) and Elovich for concentrations of 400 and 800 mg.L-1 (R2 ≈ 97%). The isotherm models used were those of Freundlich, Sips and Multilayer. Sips and Multilayer models were best fitted the equilibrium data (R2 > 96%). The maximum amount adsorbed estimated by Sips model was 33 mg.g-1. That relatively high adsorption capacity makes the buriti petiole a potential adsorbent to remove dyes.Keywords: Buriti petiole (Mauritia flexuosa L.f.). Adsorption. Textile dyes.ADSORCIÓN DEL COLORANTE TEXTIL AZUL REMAZOL POR EL PECÍOLO DE BURITI (Mauritia flexuosa L.f.)Resumen: En el presente trabajo fue investigada la retirada del colorante azul remazol usando como adsorbente el peciolo del buriti. Através del espectro infrarrojo se identificaron los principales grupos funcionales del adsorbente. La longitud de onda de absorción máxima (λmáx ) del colorante se obtuvo por espectrofotometria en UV-Visible en 595nm. El pH en el punto de carga cero del adsorbente foi aproximado graficamente en 4,6. Fueron investigados la influencia del pH, tiempo de contacto y la concentración del colorante. La capacidade de adsorción del colorante es mayor en pH's mas bajos. Los modelos cinéticos de adsorción que presentaron los mejores ajustes fueron los de pseudo-segundo orden para la menor concentración (R2 ≈ 93%) e Elovich para las concentraciones de 400 y 800 mg.L-1 (R2 ≈ 97%). Los modelos isotérmicos utilizados fueron los de Freundlich, Sips y de Multicapas. Los modelos de Sips y de Multicapas fueron los que adecuaron mejor los datos del equilibrio (R2 > 96%). La cantidad máxima adsorbida calculada por el modelo de Sips fue de 33 mg.g-1. Esta capacidad relativamente alta de adsorción define al peciolo del buriti como un adsorbente con potencial para retirar colorantes.Keywords: Peciolo de buriti (Mauritia flexuosa L.f.). Adsorción. Colorantes téxtiles
Sistema compacto de geração de energia elétrica.
The deficit of energy currently represents one of the biggest government challenges, since still there are a big number of low income communities and areas dependent on electricity with restrict access to electro-electronic gadgets such as TV set, refrigerator, and computer. This article aims to show the possibility of generating electricity generate combined with the production of frozen and/or hot water, in localities where yet doesn’t exist electricity grid or any kind of source of alternative energy. This system is based on the standard air cycle called Brayton cycle and it consists of 4LGZ model BorgWarber turbo-charger set, a combustion chamber, a power turbine connected to the gas jet turbine of the turbo-charger, a heat exchanger, a water-amonia chiller, a electrical generator of 5kVA and a command panel for the automation and energy distribution. This system which uses
either natural gas or LPG eventually will supply electricity produced in the generator, hot water obtained of the heat transfer of the combuston gases and frozen water from the chiller, having as hot source the gases coming from power system. The prototype is already being tested in laboratory
showing interesting results.O déficit de energia atualmente representa um dos maiores desafios governamentais, visto que ainda exista um grande número de comunidades de baixa renda e de áreas com acesso restrito à equipamentos eletro-eletrônicos, como televisão, geladeiras, computadores, dependentes de energia
elétrica. Este trabalho tem como objetivo, apresentar a possibilidade de geração de energia elétrica, aliada com a produção de água gelada e/ou quente, em localidades onde não existam ainda redes de transmissão ou não possua nenhum tipo de fonte de energia alternativa. O sistema é baseado no ciclo padrão a ar denominado Ciclo Brayton, e composto por um conjunto turbo-compressor modelo 4LGZ BorgWarner, uma camara de combustão, uma turbina de potência, acoplada à turbina geradora de gases do conjunto turbo-compressor, um trocador de calor, um chiller água-amônia, um gerador de 5,0 kVA e um quadro de comando para automação e distribuição de energia. Este sistema, que utiliza gás natural ou GLP, deverá fornecer energia elétrica a partir do gerador, agua quente obtida da troca térmica com os gases de combustão e água gelada a partir do chiller, tendo como a fonte quente os gases provenientes do sistema de potência. O protótipo já está sendo testado em laboratório, obtendo bons resultados
Conduction electron spin resonance in AlB2
ABSTRACT: This work reports on electron spin resonance experiments in oriented single crystals of the hexagonal AlB2 diboride compound (P6/mmm, D16h structure) which display conduction electron spin resonance. The X-band electron spin resonance spectra showed a metallic Dysonian resonance with g-value and intensity independent of temperature. The thermal broadening of the anisotropic electron spin resonance linewidth 1H tracks the T-dependence of the electrical resistivity below T ' 100 K. These results confirm the observation of a conduction electron spin resonance in AlB2 and are discussed in comparison with other boride compounds. Based on our main findings for AlB2 and the calculated electronic structure of similar layered honeycomb-like structures, we conclude that any array of covalent B–B layers potentially results in a conduction electron spin resonance signal. This observation may shed new light on the nature of the non-trivial conduction electron spin resonance-like signals of complex f-electron systems such as β-YbAlB4. Keywords: AlB2, Conduction electron, Dysonian resonance, Spin resonance
Solar models and solar neutrino oscillations
We provide a summary of the current knowledge, theoretical and experimental,
of solar neutrino fluxes and of the masses and mixing angles that characterize
solar neutrino oscillations. We also summarize the principal reasons for doing
new solar neutrino experiments and what we think may be learned from the future
measurements.Comment: Submitted to the Neutrino Focus Issue of New Journal of Physics at
http://www.njp.or
Phenomenology of Maximal and Near-Maximal Lepton Mixing
We study the phenomenological consequences of maximal and near-maximal mixing
of the electron neutrino with other (=tau and/or muon) neutrinos. We
describe the deviations from maximal mixing in terms of a parameter
and quantify the present experimental
status for . We find that the global analysis of solar neutrino
data allows maximal mixing with confidence level better than 99% for
eV^2\lsim\Delta m^2\lsim2\times10^{-7} eV. In the mass ranges \Delta
m^2\gsim 1.5\times10^{-5} eV and eV^2\lsim\Delta
m^2\lsim2\times10^{-7} eV the full interval is allowed
within 4(99.995 % CL). We suggest ways to measure in future
experiments. The observable that is most sensitive to is the rate
[NC]/[CC] in combination with the Day-Night asymmetry in the SNO detector. With
theoretical and statistical uncertainties, the expected accuracy after 5 years
is . We also discuss the effects of maximal and
near-maximal -mixing in atmospheric neutrinos, supernova neutrinos, and
neutrinoless double beta decay.Comment: 49 pages Latex file using RevTeX. 16 postscript figures included. (
Fig.2 and Fig.4 bitmapped for compression,better resolution at
http://ific.uv.es/~pppac/). Improved presentation: some statements included
and labels added in figures. Some misprint corrected. Final version to appear
in Phys. Rev D. Report no: IFIC/00-40, IASSNS-HEP-00-5
Three-Neutrino Mixing after the First Results from K2K and KamLAND
We analyze the impact of the data on long baseline \nu_\mu disappearance from
the K2K experiment and reactor \bar\nu_e disappearance from the KamLAND
experiment on the determination of the leptonic three-generation mixing
parameters. Performing an up-to-date global analysis of solar, atmospheric,
reactor and long baseline neutrino data in the context of three-neutrino
oscillations, we determine the presently allowed ranges of masses and mixing
and we consistently derive the allowed magnitude of the elements of the
leptonic mixing matrix. We also quantify the maximum allowed contribution of
\Delta m^2_{21} oscillations to CP-odd and CP-even observables at future long
baseline experiments.Comment: Some typos correcte
Radiative contribution to neutrino masses and mixing in SSM
In an extension of the minimal supersymmetric standard model (popularly known
as the SSM), three right handed neutrino superfields are introduced to
solve the -problem and to accommodate the non-vanishing neutrino masses
and mixing. Neutrino masses at the tree level are generated through parity
violation and seesaw mechanism. We have analyzed the full effect of one-loop
contributions to the neutrino mass matrix. We show that the current three
flavour global neutrino data can be accommodated in the SSM, for both
the tree level and one-loop corrected analyses. We find that it is relatively
easier to accommodate the normal hierarchical mass pattern compared to the
inverted hierarchical or quasi-degenerate case, when one-loop corrections are
included.Comment: 51 pages, 14 figures (58 .eps files), expanded introduction, other
minor changes, references adde
Chemical composition, cytotoxicity and larvicidal activity against Aedes aegypti of essential oils from Vitex gardineriana Schauer
Vitex gardneriana Schauer (Lamiaceae) popularly known as “jaramataia”, is a shrub commonly found in caatinga biome located in Northeast Brazil. In folk medicine, its leaves have been used as analgesic and anti-inflammatory agents. The chemical composition of the essential oil from leaves obtained by hydrodistillation was analyzed and identified by GC-MS and GC-FID and showing a total of 26 constituents (95.9%) being 2 monoterpenes (0.4%) and 24 sesquiterpenes (95.4%). The main constituents identified were cis-calamenene (29.7%), 6,9-guaiadiene (14.5%) and caryophyllene oxide (14.0%). The essential oil has been demonstrated high larvicidal activity againstAedes aegypti (LC50 = 28.0 μg/mL). In the evaluation of the bioassay with Artemia salina the essential oil showed LC50 = 98.11 μg/mL. Inaddition, the essential oil did not show cytotoxicity (IC50 > 2.50 mg/mL) by the hemolysis assay
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