7,304 research outputs found
Properties of Heavy B Hadrons
We review recent measurements of heavy B hadron states including masses and
lifetimes of the Bc meson as well as excited B states (B**, Bs**). We discuss
properties of the Bs meson such as lifetime, lifetime difference
delta_Gamma/Gamma and CP violation in Bs -> J/Psi Phi decays. We also summarize
new measurements of the masses and lifetimes of bottom baryons including the
Lambda_b baryon, the Sigma_b baryon states as well as the Xi_b and Omega_b
baryons.Comment: Plenary talk at ICHEP08, Philadelphia, USA, July 2008. 15 pages with
10 figures and 1 table. Fixed typo
Mesenchymal stem cells as therapeutic candidates for halting the progression of diabetic nephropathy
Mesenchymal stem cells (MSCs) possess pleiotropic properties that include immunomodulation, inhibition of apoptosis, fibrosis and oxidative stress, secretion of trophic factors, and enhancement of angiogenesis. These properties provide a broad spectrum for their potential in a wide range of injuries and diseases, including diabetic nephropathy (DN). MSCs are characterized by adherence to plastic, expression of the surface molecules CD73, CD90, and CD105 in the absence of CD34, CD45, HLA-DR, and CD14 or CD11b and CD79a or CD19 surface molecules, and multidifferentiation capacity in vitro. MSCs can be derived from many tissue sources, consistent with their broad, possibly ubiquitous distribution. This article reviews the existing literature and knowledge of MSC therapy in DN, as well as the most appropriate rodent models to verify the therapeutic potential of MSCs in DN setting. Some preclinical relevant studies are highlighted and new perspectives of combined therapies for decreasing DN progression are discussed. Hence, improved comprehension and interpretation of experimental data will accelerate the progress towards clinical trials that should assess the feasibility and safety of this therapeutic approach in humans. Therefore, MSC-based therapies may bring substantial benefit for patients suffering from DN.FAPESP (Fundacao de Amparo a Pesquisa do Estado de Sao Paulo/Sao Paulo Research Foundation) [2013/19560-6]CNPq (Conselho Nacional de Desenvolvimento Cientifico e Tecnologico/National Counsel of Technological and Scientific Development) [456959/2013-0]EFSD (European Foundation for the Study of Diabetes)Sociedade Beneficente Albert Einstein, Albert Einstein Hospital, 05652 São Paulo, SP, Brazil[University of São Paulo, 01246 São Paulo, SP, BrazilFederal University of São Paulo, 04023 São Paulo, SP, BrazilFederal University of São Paulo, 04023 São Paulo, SP, BrazilFAPESP: 2013/19560-6CNPq: 456959/2013-0Web of Scienc
Operator Product Expansion for Exclusive Decays: B^+ ->Ds^+ e+e- and B^+ -> Ds^{*+} e+e-
The decays and proceed
through a weak and an electromagnetic interaction. This is a typical ``long
distance'' process, usually difficult to compute systematically. We propose
that over a large fraction of phase space a combination of an operator product
and heavy quark expansions effectively turns this process into one in which the
weak and electromagnetic interactions occur through a local operator. Moreover,
we use heavy quark spin symmetry to relate all the local operators that appear
in leading order of the operator expansion to two basic ones. We use this
operator expansion to estimate the decay rates for .Comment: 4 pages, 1 figure, Latex, published version in PR
N-Acetylcysteine Serves as Substrate of 3-Mercaptopyruvate Sulfurtransferase and Stimulates Sulfide Metabolism in Colon Cancer Cells
Hydrogen sulfide (H2S) is an endogenously produced signaling molecule. The enzymes 3-mercaptopyruvate sulfurtransferase (MST), partly localized in mitochondria, and the inner mitochondrial membrane-associated sulfide:quinone oxidoreductase (SQR), besides being respectively involved in the synthesis and catabolism of H2S, generate sulfane sulfur species such as persulfides and polysulfides, currently recognized as mediating some of the H2S biological effects. Reprogramming of H2S metabolism was reported to support cellular proliferation and energy metabolism in cancer cells. As oxidative stress is a cancer hallmark and N-acetylcysteine (NAC) was recently suggested to act as an antioxidant by increasing intracellular levels of sulfane sulfur species, here we evaluated the effect of prolonged exposure to NAC on the H2S metabolism of SW480 colon cancer cells. Cells exposed to NAC for 24 h displayed increased expression and activity of MST and SQR. Furthermore, NAC was shown to: (i) persist at detectable levels inside the cells exposed to the drug for up to 24 h and (ii) sustain H2S synthesis by human MST more effectively than cysteine, as shown working on the isolated recombinant enzyme. We conclude that prolonged exposure of colon cancer cells to NAC stimulates H2S metabolism and that NAC can serve as a substrate for human MST
Augmented reality for innovation: Education and analysis of the glacial retreat of the Peruvian Andean snow-capped mountains
Mountain glaciers are considered great reservoirs of water, and their importance lies in the fact that many of our ecosystems and numerous communities depend on them; Peru has one of the largest extensions of Andean snow-capped mountains, which have been affected by the decline in their glacier coverage and that is warned, will disappear due to environmental conditions and alterations in the current global temperature. This problem has increased due to ignorance, misinformation, indifference, and lack of solidarity on the part of the population who favors this discouraging situation. Taking advantage of the current technological immersion, in which we live, the development of a mobile application was proposed as a pedagogical resource to raise awareness among educational institutions about the glacial retreat of the Peruvian Andean snow-capped mountains, showing the current situation of some of the snow-capped mountains of the Andes that have suffered a greater impact, implementing augmented reality technology to obtain an interactive link. To provide greater detail of the situation, previous studies were carried out on glacial retreats in two Peruvian snow-capped mountains over the last 40 years, where it was found that, of the snow-capped mountains considered, Chicon had a decrease of 32.5% of its glacier cover, and Pumahuanca had a decrease of 56.9%. Such results are exposed within the application to provide realistic data on the glacial conditions of both Peruvian snow-capped mountains, as well as the consequences and conservation techniques to mitigate and cope with deglaciation. Taking into consideration that environmental education from an early age turns out to be key to forming an informed and participatory society about climate change
Determination of the Jet Energy Scale at the Collider Detector at Fermilab
A precise determination of the energy scale of jets at the Collider Detector
at Fermilab at the Tevatron collider is described. Jets are used in
many analyses to estimate the energies of partons resulting from the underlying
physics process. Several correction factors are developed to estimate the
original parton energy from the observed jet energy in the calorimeter. The jet
energy response is compared between data and Monte Carlo simulation for various
physics processes, and systematic uncertainties on the jet energy scale are
determined. For jets with transverse momenta above 50 GeV the jet energy scale
is determined with a 3% systematic uncertainty
"The Public Health Contribution of Sentiment Analysis of Monkeypox Tweets to Detect Polarities Using the CNN-LSTM Model"
"Monkeypox is a rare disease caused by the monkeypox virus. This disease was considered
eradicated in 1980 and was believed to affect rodents and not humans. However, recent years have
seen a massive outbreak of monkeypox in humans, setting off worldwide alerts from health agencies.
As of September 2022, the number of confirmed cases in Peru had reached 1964. Although most
monkeypox patients have been discharged, we cannot neglect the monitoring of the population
with respect to the monkeypox virus. Lately, the population has started to express their feelings
and opinions through social media, specifically Twitter, as it is the most used social medium and is
an ideal space to gather what people think about the monkeypox virus. The information imparted
through this medium can be in different formats, such as text, videos, images, audio, etc. The objective
of this work is to analyze the positive, negative, and neutral feelings of people who publish their
opinions on Twitter with the hashtag #Monkeypox. To find out what people think about this disease,
a hybrid-based model architecture built on CNN and LSTM was used to determine the prediction
accuracy. The prediction result obtained from the total monkeypox data was 83% accurate. Other
performance metrics were also used to evaluate the model, such as specificity, recall level, and F1
score, representing 99%, 85%, and 88%, respectively. The results also showed the polarity of feelings
through the CNN-LSTM confusion matrix, where 45.42% of people expressed neither positive nor
negative opinions, while 19.45% expressed negative and fearful feelings about this infectious disease.
The results of this work contribute to raising public awareness about the monkeypox virus.
B Physics at the Tevatron: Run II and Beyond
This report provides a comprehensive overview of the prospects for B physics
at the Tevatron. The work was carried out during a series of workshops starting
in September 1999. There were four working groups: 1) CP Violation, 2) Rare and
Semileptonic Decays, 3) Mixing and Lifetimes, 4) Production, Fragmentation and
Spectroscopy. The report also includes introductory chapters on theoretical and
experimental tools emphasizing aspects of B physics specific to hadron
colliders, as well as overviews of the CDF, D0, and BTeV detectors, and a
Summary.Comment: 583 pages. Further information on the workshops, including
transparencies, can be found at the workshop's homepage:
http://www-theory.lbl.gov/Brun2/. The report is also available in 2-up
http://www-theory.lbl.gov/Brun2/report/report2.ps.gz or chapter-by-chapter
http://www-theory.lbl.gov/Brun2/report
The Semileptonic Decays and from QCD Sum Rules
We investigate the semileptonic decays of B and D mesons into and
mesons, respectively, by means of QCD sum rules. We find that for the
vector formfactors involved the pole dominance hypothesis is valid to good
accuracy with pole masses in the expected range. Pole dominance, however, does
not apply to the axial formfactors which results in specific predictions for
the predominant polarization of the meson and the shape of the lepton
spectrum. For the total decay rates we find , , and .Comment: 23 pages, 12 figures included as uu-encoded file, needs REVTEX,
TUM--T31--39/9
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