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The Large Underground Xenon (LUX) experiment is a dual-phase xenon time-projection chamber operating at the Sanford Underground Research Facility (Lead, South Dakota). The LUX cryostat was filled for the first time in the underground laboratory in February 2013. We report results of the first WIMP search data set, taken during the period from April to August 2013, presenting the analysis of 85.3 live days of data with a fiducial volume of 118 kg. A profile-likelihood analysis technique shows our data to be consistent with the background-only hypothesis, allowing 90% confidence limits to be set on spin-independent WIMP-nucleon elastic scattering with a minimum upper limit on the cross section of 7.6 × 10(-46) cm(2) at a WIMP mass of 33 GeV/c(2). We find that the LUX data are in disagreement with low-mass WIMP signal interpretations of the results from several recent direct detection experiments.
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Yeast derivatives are used in winemaking for a variety of purposes, including the protection of wines from oxidation. In this work, by the application of an autoclave extraction method, different fractions were obtained from red wine lees and a lab-grown culture of the same yeast strain. Each extract was characterized for their protein, polysaccharide, glutathione, thiol, and polyphenol contents. The antioxidant activity was tested by adding each extract in a model wine enriched with catechin and saturated with oxygen. The presence of both wine lees and lab-grown yeast extracts delayed oxygen consumption when compared to the untreated control. This delay was confirmed by the development of a yellow color, which was lower in 5 out of 6 of the samples added with yeast/lees extracts. The electrochemical behavior of the samples also showed a greater resistance to oxidation, thus suggesting a protective role of the wine lees extracts against wine oxidative phenomena.
Assuntos
Vinho , Vinho/análise , Antioxidantes/metabolismo , Fenóis/química , Saccharomyces cerevisiae/metabolismo , Polifenóis/metabolismoRESUMO
The T2K Collaboration reports a precision measurement of muon neutrino disappearance with an off-axis neutrino beam with a peak energy of 0.6 GeV. Near detector measurements are used to constrain the neutrino flux and cross section parameters. The Super-Kamiokande far detector, which is 295 km downstream of the neutrino production target, collected data corresponding to 3.01×10(20) protons on target. In the absence of neutrino oscillations, 205±17 (syst) events are expected to be detected while only 58 muon neutrino event candidates are observed. A fit to the neutrino rate and energy spectrum, assuming three neutrino flavors and normal mass hierarchy yields a best-fit mixing angle sin2(θ23)=0.514±0.082 and mass splitting |Δm(32)(2)|=2.44(-0.15)(+0.17)×10(-3) eV2/c4. Our result corresponds to the maximal oscillation disappearance probability.
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At submonolayer coverage, Mn forms atomic wires on the Si(001) surface oriented perpendicular to the underlying Si dimer rows. While many other elements form symmetric dimer wires at room temperature, we show that Mn wires have an asymmetric appearance and pin the Si dimers nearby. We find that an atomic configuration with a Mn trimer unit cell can explain these observations as due to the interplay between the Si dimer buckling phase near the wire and the orientation of the Mn trimer. We study the resulting four wire configurations in detail using high-resolution scanning tunneling microscopy (STM) imaging and compare our findings with the STM images simulated by density functional theory.
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BACKGROUND: The COVID-19 pandemic has impacted all aspects of modern-day oncology, including how stakeholders communicate through social media. We surveyed oncology stakeholders in order to assess their attitudes pertaining to social media and how it has been affected during the pandemic. MATERIALS AND METHODS: A 40-item survey was distributed to stakeholders from 8 July to 22 July 2020 and was promoted through the European Society for Medical Oncology (ESMO) and the OncoAlert Network. RESULTS: One thousand and seventy-six physicians and stakeholders took part in the survey. In total, 57.3% of respondents were medical oncologists, 50.6% aged <40 years, 50.8% of female gender and mostly practicing in Europe (51.5%). More than 90% of respondents considered social media a useful tool for distributing scientific information and for education. Most used social media to stay up to date on cancer care in general (62.5%) and cancer care during COVID-19 (61%) given the constant flow of information. Respondents also used social media to interact with other oncologists (78.8%) and with patients (34.4%). Overall, 61.1% of respondents were satisfied with the role that social media was playing during the COVID-19 pandemic. On the other hand, 41.1% of respondents reported trouble in discriminating between credible and less credible information and 30% stated social networks were a source of stress. For this reason, one-third of respondents reduced its use during the COVID-19 pandemic. Regarding meeting attendance, a total of 59.1% of responding physicians preferred in-person meetings to virtual ones, and 51.8% agreed that virtual meetings and social distancing could hamper effective collaboration. CONCLUSION: Social media has a useful role in supporting cancer care and professional engagement in oncology. Although one-third of respondents reported reduced use of social media due to stress during the COVID-19 pandemic, the majority found social media useful to keep up to date and were satisfied with the role social media was playing during the pandemic.
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COVID-19 , Oncologistas , Mídias Sociais , Adulto , Idoso , Atitude do Pessoal de Saúde , Atitude Frente aos Computadores , Feminino , Humanos , Disseminação de Informação , Masculino , Oncologia/educação , Pessoa de Meia-Idade , Oncologistas/psicologia , Rede Social , Estresse Psicológico , Inquéritos e Questionários , TelemedicinaRESUMO
The proteins of wheat flour have several biological activities that can affect human health and physiology when wheat-based foods are consumed. The modifications of bread crumb and crust proteins during an in vitro peptic/pancreatic digestion process were studied by electrophoresis and immunoblotting with polyclonal antibodies specific for single proteins or groups of homologous proteins of the wheat flour, and the results were compared to those obtained for an unheated dough sample. The results show that baking affects the extent of proteolysis and the immunological and physicochemical features of the digestion products in relation to the level of the heat treatment. Therefore, the results concerning the digestion of the unheated wheat flour or dough are not representative of what happens when baked products enter the human digestive tract.
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Manipulação de Alimentos/métodos , Proteínas de Plantas/metabolismo , Triticum , Pão , Digestão , Eletroforese em Gel de Ágar , Farinha , Temperatura Alta , Immunoblotting , Peptídeo HidrolasesRESUMO
The effect of baking and digestion on the allergenicity of wheat flour proteins has been studied. Pooled sera of patients suffering from food allergy to wheat products were tested for IgE binding to the proteins of the wheat dough and of the bread crumb and crust, before and after being in vitro digested. During in vitro digestion, the IgE binding protein components of the unheated dough tended to disappear, whereas a permanence of IgE recognition was evident for both the bread crumb and crust. This indicates that the baking process increases the resistance of the potential allergens of the wheat flour to proteolytic digestion, allowing them to reach the gastrointestinal tract, where they can elicit the immunological response. Therefore, the effects of baking must be carefully considered in studying food allergies to wheat products.
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Pão , Culinária , Digestão , Hipersensibilidade a Trigo , Eletroforese em Gel de Poliacrilamida , Humanos , Imunoglobulina E/sangue , Técnicas In Vitro , Proteínas de Plantas/metabolismo , Ligação ProteicaRESUMO
The MiniBooNE Collaboration reports a search for nu_{micro} and nu[over]_{micro} disappearance in the Deltam;{2} region of 0.5-40 eV;{2}. These measurements are important for constraining models with extra types of neutrinos, extra dimensions, and CPT violation. Fits to the shape of the nu_{micro} and nu[over]_{micro} energy spectra reveal no evidence for disappearance at the 90% confidence level (C.L.) in either mode. The test of nu[over]_{micro} disappearance probes a region below Deltam;{2} = 40 eV;{2} never explored before.
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Using high statistics samples of charged-current numu interactions, the MiniBooNE [corrected] Collaboration reports a measurement of the single-charged-pion production to quasielastic cross section ratio on mineral oil (CH2), both with and without corrections for hadron reinteractions in the target nucleus. The result is provided as a function of neutrino energy in the range 0.4 GeV
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We report the first observation of off-axis neutrino interactions in the MiniBooNE detector from the NuMI beam line at Fermilab. The MiniBooNE detector is located 745 m from the NuMI production target, at 110 mrad angle (6.3 degrees) with respect to the NuMI beam axis. Samples of charged-current quasielastic numicro and nue interactions are analyzed and found to be in agreement with expectation. This provides a direct verification of the expected pion and kaon contributions to the neutrino flux and validates the modeling of the NuMI off-axis beam.
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The MiniBooNE Collaboration observes unexplained electronlike events in the reconstructed neutrino energy range from 200 to 475 MeV. With 6.46x10;{20} protons on target, 544 electronlike events are observed in this energy range, compared to an expectation of 415.2+/-43.4 events, corresponding to an excess of 128.8+/-20.4+/-38.3 events. The shape of the excess in several kinematic variables is consistent with being due to either nu_{e} and nu[over ]_{e} charged-current scattering or nu_{mu} neutral-current scattering with a photon in the final state. No significant excess of events is observed in the reconstructed neutrino energy range from 475 to 1250 MeV, where 408 events are observed compared to an expectation of 385.9+/-35.7 events.
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The observation of neutrino oscillations is clear evidence for physics beyond the standard model. To make precise measurements of this phenomenon, neutrino oscillation experiments, including MiniBooNE, require an accurate description of neutrino charged current quasielastic (CCQE) cross sections to predict signal samples. Using a high-statistics sample of nu_(mu) CCQE events, MiniBooNE finds that a simple Fermi gas model, with appropriate adjustments, accurately characterizes the CCQE events observed in a carbon-based detector. The extracted parameters include an effective axial mass, M_(A)(eff)=1.23+/-0.20 GeV, that describes the four-momentum dependence of the axial-vector form factor of the nucleon, and a Pauli-suppression parameter, kappa=1.019+/-0.011. Such a modified Fermi gas model may also be used by future accelerator-based experiments measuring neutrino oscillations on nuclear targets.
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The MiniBooNE Collaboration reports first results of a search for nu e appearance in a nu mu beam. With two largely independent analyses, we observe no significant excess of events above the background for reconstructed neutrino energies above 475 MeV. The data are consistent with no oscillations within a two-neutrino appearance-only oscillation model.
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A recently introduced new methodology based on ultrashort (50-100 ps) molecular dynamics simulations with a quantum-refined force-field (QRFF-MD) is here evaluated in its ability both to predict protein-ligand binding affinities and to discriminate active compounds from inactive ones. Physically based scoring functions are derived from this approach, and their performance is compared to that of several standard knowledge-based scoring functions. About 40 inhibitors of cyclin-dependent kinase 2 (CDK2) representing a broad chemical diversity were considered. The QRFF-MD method achieves a correlation coefficient, R(2), of 0.55, which is significantly better than that obtained by a number of traditional approaches in virtual screening but only slightly better than that obtained by consensus scoring (R(2) = 0.50). Compounds from the Available Chemical Directory, along with the known active compounds, were docked into the ATP binding site of CDK2 using the program Glide, and the 650 ligands from the top scored poses were considered for a QRFF-MD analysis. Combined with structural information extracted from the simulations, the QRFF-MD methodology results in similar enrichment of known actives compared to consensus scoring. Moreover, a new scoring function is introduced that combines a QRFF-MD based scoring function with consensus scoring, which results in substantial improvement on the enrichment profile.
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Simulação por Computador , Quinase 2 Dependente de Ciclina/antagonistas & inibidores , Avaliação Pré-Clínica de Medicamentos/métodos , Inibidores Enzimáticos/farmacologia , Quinase 2 Dependente de Ciclina/química , Quinase 2 Dependente de Ciclina/metabolismo , Bases de Dados Factuais , Inibidores Enzimáticos/química , Inibidores Enzimáticos/metabolismo , Ligantes , Modelos Moleculares , Estrutura Molecular , Ligação Proteica , Curva ROC , Software , Relação Estrutura-AtividadeRESUMO
Five cellulase components were identified and purified in one step from Streptomyces strain A20 using electroendosmotic preparative electrophoresis. By this procedure up to 18 mg of protein mixture could be loaded on the column, with an estimated recovery of 60-70% of total activity; activity and protein recovery could be estimated 32% and 47% respectively, if only activity peaks were considered. In comparison to other purification methods, this technique results in high protein recovery and resolution of applied samples.
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Celulase/isolamento & purificação , Streptomyces/análise , Proteínas de Bactérias/análise , Eletroforese , Eletroforese em Gel de PoliacrilamidaRESUMO
Proteins extracted from gluten of the bread wheat cultivar Fiorello 2 in the presence of 2-mercaptoethanol or dithiothreitol were separated by isoelectric focusing in a free solution in a pH 3-10 gradient containing 50% v/v 1-propanol or urea. The collected fractions were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis in 10% gels (high and medium molecular weight glutenin subunits) and 16% gels (low molecular weight gliadins). The isoelectric focusing pattern of gluten polypeptides in 50% v/v 1-propanol was comparable to that obtained on two-dimensional gel electrophoresis, based on isoelectric focusing and polyacrylamide gel electrophoresis or nonequilibrium pH gradient electrophoresis and polyacrylamide gel electrophoresis. A similar isoelectric focusing pattern was also observed when 3M urea was used as solvent. New gluten polypeptides, similar in mobility to the high molecular weight subunits of glutenin were detected at acidic pH.
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Glutens/análise , Triticum/análise , 1-Propanol , Alquilação , Eletroforese em Gel de Poliacrilamida , Concentração de Íons de Hidrogênio , Focalização Isoelétrica/métodos , Oxirredução , UreiaRESUMO
BACKGROUND: The few cases of food allergy to fig reported to date, whose main manifestations were anaphylactic reactions, have been related to a cross-sensitisation to weeping fig (Ficus benjamina) or to the 'latex-fruit syndrome'. Here we report on two cases of the oral allergy syndrome (OAS) to fig in patients whose main allergic manifestations were related to sensitisation to grass and birch pollens. METHODS: The patients were characterised by clinical history, skin prick tests (SPT) with commercial and in-house extracts, prick-by-prick test, specific IgE measurements and challenge tests. PBS-soluble and insoluble extracts of both fig skin and pulp were examined for the presence of potential allergens by IgE immunoblotting. RESULTS: Both patients showed OAS followed by respiratory symptoms when challenged with fig. They were negative in both specific IgE detection and SPT with commercial extracts of fig and many other plant materials, including F. benjamina and Hevea Brasiliensis, while grass and birch pollens gave positive results. Prick-by-prick tests and SPT with in-house extracts indicated that the fig skin had a much higher allergenicity than the pulp. Despite negative IgE detection by the CAP assay, immunoblotting experiments showed that potential fig allergens were PBS-soluble and present only in the skin of the fruit. CONCLUSIONS: OAS to fig followed by respiratory symptoms can be present in patients not sensitised to weeping fig or having the latex-fruit syndrome. Different parts of the fig can have different allergenicities, the most important allergens being proteins related to the skin of the fruit. Improved commercial fig extracts to be used for the diagnosis of this type of allergy have to be developed.
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Ficus/efeitos adversos , Ficus/imunologia , Hipersensibilidade Alimentar/imunologia , Adulto , Testes de Provocação Brônquica , Feminino , Hipersensibilidade Alimentar/diagnóstico , Hipersensibilidade Alimentar/etiologia , Humanos , Imunoglobulina E/sangue , Mucosa Bucal/imunologia , Testes CutâneosRESUMO
BACKGROUND: Allergy to almonds has been frequently reported, but data on the identification of the almond allergens, as well as on the reliability of the methods for in vitro detection of specific IgE for these allergens, are scant. This study aimed to identify the almond allergens and to evaluate the reliability of the CAP-FEIA as the standard system for detection of almond-specific IgE with clinical significance. METHODS: Immunoblotting performed with an almond-protein extract was carried out on the sera of five patients who had previously been tested by the CAP-FEIA system; two of these patients had tested negative with the CAP-FEIA system but suffered life-threatening laryngeal edema after eating almonds, whereas the other three subjects, who had tested positive with CAP-FEIA, did not present any symptoms subsequent to almond ingestion. RESULTS: The sera of the two symptomatic CAP-FEIA-negative patients had IgE that bound only to a 37-kDa protein in immunoblotting. On the contrary, the sera of the three asymptomatic subjects all showed IgE binding to two almond proteins of 62 and 50 kDa, corresponding to the glycosylated components of the extract. CONCLUSIONS: The results here presented suggest that, at least for the examined subjects, the positivity to almond, as measured with a standard laboratory method, is due to the presence of the 62/50-kDa glycoproteins with little or no immunologic significance, and not to the binding to the 37-kDa polypeptide, which appears to be a true almond allergen.
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Hipersensibilidade Alimentar/diagnóstico , Imunoglobulina E/metabolismo , Nozes/efeitos adversos , Proteínas de Plantas/metabolismo , Rosales , Adulto , Ensaio de Imunoadsorção Enzimática , Reações Falso-Negativas , Reações Falso-Positivas , Feminino , Hipersensibilidade Alimentar/etiologia , Humanos , Immunoblotting , Imunoglobulina E/sangue , Imunoglobulina E/imunologia , Masculino , Nozes/imunologia , Proteínas de Plantas/imunologiaRESUMO
A simple method for the visualisation of wine yeast esterase (carboxylesterase EC 3.1.1.1) activity on electrophoretic gels was developed, using the fluorescent substrate fluorescein diacetate. The zymogram system allows a sensitive detection of esterase bands in only 5 min of incubation of both native and sodium dodecyl sulfate gels.