651 research outputs found
Cambrian ensialic rift-related magmatism in the Ossa-Morena Zone
The Late Ediacaran (c. 560â550 Ma) SĂŠrie Negra sediments of the ĂvoraâAracena metamorphic belt, Ossa-Morena Zone, SW Iberian Massif,
preserve a record of the erosion of an AvalonianâCadomian magmatic arc and subsequent related turbiditic sedimentation. Detrital zircon from the
SĂŠrie Negra is characterized by predominantly Ediacaran and Cryogenian ages, with few Paleoproterozoic and Archean cores, and a marked lack
of Grenvillian ages. These features, when combined with the metasediments' enrichment in LREE (La/Yb=14), negative Eu-anomalies, low
147Sm/144Nd values (0.121) and negative ÎľNd550=â5.5, indicate that the protolith SĂŠrie Negra sediments were derived from a continental
magmatic arc.
A period of Late Cadomian (ca. 560â540 Ma) tectonism was followed by an extended episode of widespread bimodal magmatism related to
Cambrian (ca. 540â500 Ma) rifting. This tectonic inversion is expressed in the geological record by a regional Early Cambrian unconformity.
SHRIMP zircon UâThâPb ages from four felsic orthogneisses from the Ăvora Massif record Cambrian (527Âą10 Ma, 522Âą5 Ma, 517Âą6 Ma
and 505Âą5 Ma) crystallization ages for their igneous protoliths. This confirms the existence of widespread Lower Paleozoic igneous activity in the
Ossa-Morena Zone: (i) a Lower Cambrian (ca. 535â515 Ma) igneousâfelsic dominatedâsedimentary complex (with calc-alkaline signature and
associated carbonate and siliciclastic deposition), and (ii) a Middle Cambrianâ?Ordovician (ca. 515â490 Ma) igneousâbimodalâsedimentary
complex (with calc-alkaline and tholeiitic signatures and associated dominant siliciclastic deposition, but also carbonate sediments).
The Cambrian felsic magmatism was characterized by negative Eu-anomalies, (La/Lu)N=0.8â11, 147Sm/144Nd=0.1289â0.1447 and ÎľNd500
ranging from â1.5 to â0.8. A tendency towards peraluminous compositions suggests late fractionation, low degrees of partial melting, or the
mixing of crustal and mantle-derived material in the magma source region. Some felsic rocks possibly represent the last residual melts of hightemperature,
zircon-undersaturated mafic magmas later affected by crustal contamination, while others indicate partial melting of crustal
metasediments variably contaminated by basaltic liquids.
The transition from early felsic dominated to later more mafic magmatism suggests the gradual opening of the system to tholeiitic NâE-MORB
products (ThN/TaNb1.0). The as yet undated (Cambrianâ?Ordovician) E-MORB amphibolites have 147Sm/144Nd=0.1478â0.1797 and ÎľNd500
values ranging from +6.4 to +7.3, while the N-MORB amphibolites have 147Sm/144Nd=0.1818â0.1979 and ÎľNd500 values of +5.8 and +7.0,
reaching a maximum of +9.1. In contrast, other amphibolites have a negative Ta-anomaly (1.35bThN/TaNb2.41) reminiscent of lavas from
âorogenicâ settings or alternatively, typical of crustally-contaminated within-plate magmas. These âVAB-likeâ amphibolites have 147Sm/144Nd
values ranging from 0.1639 to 0.1946 and ÎľNd500 values of +3.5 to +5.2, suggesting derivation by crustal assimilation processes. The subalkaline
igneous precursors of the amphibolites were most likely generated in a rift setting by asthenospheric upwelling. These results strengthen the proposed geodynamic scenarios for the SW Iberian Massif by which Cadomian accretion gave rise to an ensialic
rift that developed into a proto-oceanic basin and incipient spreading (opening of the Rheic Ocean?). A similar transition from a convergent to a
divergent plate boundary during the Ediacaran to Cambrianâ?Ordovician has also been reported in other segments of the northern Gondwana
margin
The Absence of MIST1 Leads to Increased Ethanol Sensitivity and Decreased Activity of the Unfolded Protein Response in Mouse Pancreatic Acinar Cells
Background: Alcohol abuse is a leading cause of pancreatitis in humans. However, rodent models suggest that alcohol only sensitizes the pancreas to subsequent insult, indicating that additional factors play a role in alcohol-induced pancreatic injury. The goal of this study was to determine if an absence of MIST1, a transcription factor required for complete differentiation of pancreatic acinar cells in mice, increased the sensitivity to alcohol. Methods: Two to four month-old mice lacking MIST1 (Mist1 2/2) or congenic C57 Bl6 mice were placed on a Lieber-DeCarli diet (36 % of total kcal from ethanol and fat), a control liquid diet (36 % kcal from fat) or a regular breeding chow diet (22% kcal from fat). After six weeks, pancreatic morphology was assessed. Biochemical and immunofluorescent analysis was used to assess mediators of the unfolded protein response (UPR). Results: Ethanol-fed Mist1 2/2 mice developed periductal accumulations of inflammatory cells that did not appear in wild type or control-fed Mist1 2/2 mice. Wild type mice fed diets high in ethanol or fat showed enhancement of the UPR based on increased accumulation of peIF2a and spliced XBP1. These increases were not observed in Mist1 2/2 pancreatic tissue, which had elevated levels of UPR activity prior to diet exposure. Indeed, exposure to ethanol resulted in a reduction of UPR activity in Mist1 2/2 mice. Conclusions: Our findings suggest that an absence of MIST1 increases the sensitivity to ethanol that correlated wit
Performance of purslane biomass production (Portulaca oleracea) under different organic substrate concentrations
Objectives: To evaluate different concentrations based on cattle manure as an alternative in purslane production. Methodology: The experiment was conducted in a greenhouse at the Center for Agricultural Sciences and Engineering of the Federal University of Espirito Santo in Alegre, ES/ Brazil. The experimental arrangement used was a completely randomized design (CRD) with 5 treatments and 6 replications. The treatments consisted of distinct dosages of the substrate based on cattle manure (0 mL; 125 mL; 250 mL; 500 mL and 1000 mL), which were applied in 5 L of soil, considered as an experimental unit. Root dry mass and aerial dry mass were evaluated. Results: Application of 500 mL of cattle manure provided a higher accumulation of shoot dry mass (25 g/plant). For root dry mass, there were no statistically significant differences. Conclusions: Under the conditions of the present work, it is concluded that the use of organic manure with cattle manure is viable.Keywords: Organic fertilization, fertilization levels, cattle manure; dry weight
Concomitant Active Tuberculosis Prolongs Survival in Non-Small Cell Lung Cancer: A Study in a Tuberculosis-Endemic Country
BACKGROUND: Adjuvant tumor cell vaccine with chemotherapy against non-small cell lung cancer (NSCLC) shows limited clinical response. Whether it provokes effective cellular immunity in tumor microenvironment is questionable. Concomitant active tuberculosis in NSCLC (TBLC) resembles locoregional immunotherapy of tumor cell vaccine; thus, maximally enriches effective anti-tumor immunity. This study compares the survival and immunological cell profile in TBLC over NSCLC alone. METHODS: Retrospective review of NSCLC patients within 1-year-period of 2007 and follow-up till 2010. RESULTS: A total 276 NSCLC patients were included. The median survival of TBLC is longer than those of NSCLC alone (11.6 vs. 8.8 month, p<0.01). Active tuberculosis is an independent predictor of better survival with HR of 0.68 (95% CI, 0.48 ~ 0.97). Squamous cell carcinoma (SCC) (55.8 vs. 31.7%, p<0.01) is a significant risk factor for NSCLC with active TB. The median survival of SCC with active tuberculosis is significantly longer than adenocarcinoma or undetermined NSCLC with TB (14.2 vs. 6.6 and 2.8 months, p<0.05). Active tuberculosis in SCC increases the expression of CD3 (46.4 Âą 24.8 vs. 24.0 Âą 16.0, p<0.05), CXCR3 (35.1 Âą 16.4 vs. 19.2 Âą 13.3, p<0.01) and IP-10 (63.5 Âą 21.9 vs. 35.5 Âą 21.0, p<0.01), while expression of FOXP3 is decreased (3.5 Âą 0.5 vs. 13.3 Âą 3.7 p<0.05, p<0.05). Survival of SCC with high expression of CD3 (12.1 vs. 3.6 month, p<0.05) and CXCR3 (12.1 vs. 4.4 month, p<0.05) is longer than that with low expression. CONCLUSIONS: Active tuberculosis in NSCLC shows better survival outcome. The effective T lymphocyte infiltration in tumor possibly underlies the mechanism. Locoregional immunotherapy of tumor cell vaccine may deserve further researches
Comparative Analysis of Gene Content Evolution in Phytoplasmas and Mycoplasmas
Phytoplasmas and mycoplasmas are two groups of important pathogens in the bacterial class Mollicutes. Because of their economical and clinical importance, these obligate pathogens have attracted much research attention. However, difficulties involved in the empirical study of these bacteria, particularly the fact that phytoplasmas have not yet been successfully cultivated outside of their hosts despite decades of attempts, have greatly hampered research progress. With the rapid advancements in genome sequencing, comparative genome analysis provides a new approach to facilitate our understanding of these bacteria. In this study, our main focus is to investigate the evolution of gene content in phytoplasmas, mycoplasmas, and their common ancestor. By using a phylogenetic framework for comparative analysis of 12 complete genome sequences, we characterized the putative gains and losses of genes in these obligate parasites. Our results demonstrated that the degradation of metabolic capacities in these bacteria has occurred predominantly in the common ancestor of Mollicutes, prior to the evolutionary split of phytoplasmas and mycoplasmas. Furthermore, we identified a list of genes that are acquired by the common ancestor of phytoplasmas and are conserved across all strains with complete genome sequences available. These genes include several putative effectors for the interactions with hosts and may be good candidates for future functional characterization
Measurement of the t(t)over-bar production cross section in the dilepton channel in pp collisions at âs=8 TeV
The top-antitop quark (t (t) over bar) production cross section is measured in proton-proton collisions at root s = 8 TeV with the CMS experiment at the LHC, using a data sample corresponding to an integrated luminosity of 5.3 fb(-1). The measurement is performed by analysing events with a pair of electrons or muons, or one electron and one muon, and at least two jets, one of which is identified as originating from hadronisation of a bottom quark. The measured cross section is 239 +/- 2 (stat.) +/- 11 (syst.) +/- 6 (lum.) pb, for an assumed top-quark mass of 172.5 GeV, in agreement with the prediction of the standard model
Performance of CMS muon reconstruction in pp collision events at sqrt(s) = 7 TeV
The performance of muon reconstruction, identification, and triggering in CMS
has been studied using 40 inverse picobarns of data collected in pp collisions
at sqrt(s) = 7 TeV at the LHC in 2010. A few benchmark sets of selection
criteria covering a wide range of physics analysis needs have been examined.
For all considered selections, the efficiency to reconstruct and identify a
muon with a transverse momentum pT larger than a few GeV is above 95% over the
whole region of pseudorapidity covered by the CMS muon system, abs(eta) < 2.4,
while the probability to misidentify a hadron as a muon is well below 1%. The
efficiency to trigger on single muons with pT above a few GeV is higher than
90% over the full eta range, and typically substantially better. The overall
momentum scale is measured to a precision of 0.2% with muons from Z decays. The
transverse momentum resolution varies from 1% to 6% depending on pseudorapidity
for muons with pT below 100 GeV and, using cosmic rays, it is shown to be
better than 10% in the central region up to pT = 1 TeV. Observed distributions
of all quantities are well reproduced by the Monte Carlo simulation.Comment: Replaced with published version. Added journal reference and DO
Performance of CMS muon reconstruction in pp collision events at sqrt(s) = 7 TeV
The performance of muon reconstruction, identification, and triggering in CMS
has been studied using 40 inverse picobarns of data collected in pp collisions
at sqrt(s) = 7 TeV at the LHC in 2010. A few benchmark sets of selection
criteria covering a wide range of physics analysis needs have been examined.
For all considered selections, the efficiency to reconstruct and identify a
muon with a transverse momentum pT larger than a few GeV is above 95% over the
whole region of pseudorapidity covered by the CMS muon system, abs(eta) < 2.4,
while the probability to misidentify a hadron as a muon is well below 1%. The
efficiency to trigger on single muons with pT above a few GeV is higher than
90% over the full eta range, and typically substantially better. The overall
momentum scale is measured to a precision of 0.2% with muons from Z decays. The
transverse momentum resolution varies from 1% to 6% depending on pseudorapidity
for muons with pT below 100 GeV and, using cosmic rays, it is shown to be
better than 10% in the central region up to pT = 1 TeV. Observed distributions
of all quantities are well reproduced by the Monte Carlo simulation.Comment: Replaced with published version. Added journal reference and DO
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