925 research outputs found
Decay of flux vacua to nothing
We construct instanton solutions describing the decay of flux
compactifications of a gauge theory by generalizing the Kaluza-Klein
bubble of nothing. The surface of the bubble is described by a smooth
magnetically charged solitonic brane whose asymptotic flux is precisely that
responsible for stabilizing the 4d compactification. We describe several
instances of bubble geometries for the various vacua occurring in a
Einstein-Maxwell theory namely, AdS_4 x S^2, R^{1,3} x S^2, and dS_4 x S^2.
Unlike conventional solutions, the bubbles of nothing introduced here occur
where a {\em two}-sphere compactification manifold homogeneously degenerates.Comment: 31 pages, 15 figure
Plasticity of the MAPK signaling network in response to mechanical stress
Cells display versatile responses to mechanical inputs and recent studies have identified the mitogen-activated protein kinase (MAPK) cascades mediating the biological effects observed upon mechanical stimulation. Although, MAPK pathways can act insulated from each other, several mechanisms facilitate the crosstalk between the components of these cascades. Yet, the combinatorial complexity of potential molecular interactions between these elements have prevented the understanding of their concerted functions. To analyze the plasticity of the MAPK signaling network in response to mechanical stress we performed a non-saturating epistatic screen in resting and stretched conditions employing as readout a JNK responsive dJun-FRET biosensor. By knocking down MAPKs, and JNK pathway regulators, singly or in pairs in Drosophila S2R+ cells, we have uncovered unexpected regulatory links between JNK cascade kinases, Rho GTPases, MAPKs and the JNK phosphatase Puc. These relationships have been integrated in a system network model at equilibrium accounting for all experimentally validated interactions. This model allows predicting the global reaction of the network to its modulation in response to mechanical stress. It also highlights its context-dependent sensitivity
Relación entre las concentraciones de polen aéreo de Artemisia, Chenopodiaceae, Plantago y Taraxacum y la prevalencia de polinosis en estudiantes universitarios de León
XV lnternational A.P.L.E. Symposium of Palynolog
Seasonal evolution of hydrophilic and hydrophobic peptide contents in cheeses made from ewe's goat's or cow's milk
Proteolysis is the principal and most complex biochemical event occurring during the maturation of the
majority of ripened cheese varieties. In addition to softening the cheese body, proteolysis influences the development
of cheese flavour via the formation of amino acid and peptides which make a direct contribution to flavour. Goat,
cow and sheep cheeses have been elaborated with raw milk and calf rennet. The extent of proteolysis was monitored
over six months of ripening and means of HPLC peptide profile analysis. The influence of season on the changes in
hydrophobic and hydrophilic peptides and the HO/HI ratio during the ripening of the cheeses were studie
Uropathogenic Escherichia coli (UPEC) strains may carry virulence properties of diarrhoeagenic E-coli
To analyze whether Escherichia coli strains that cause urinary tract infections (UPEC) share virulence characteristics with the diarrheagenic E. coli (DEC) pathotypes and to recognize their genetic diversity, 225 UPEC strains were examined for the presence of various properties of DEC and UPEC (type of interaction with HeLa cells, serogroups and presence of 30 virulence genes). No correlation between adherence patterns and serogroups was observed. Forty-five serogroups were found, but 64% of the strains belonged to one of the 12 serogroups (O1, O2, O4, O6, O7, O14, O15, O18, O21, O25, O75, and O175) and carried UPEC virulence genes (pap, hly, aer, sfa, cnf). the DEC genes found were: aap, aatA, aggC, agg3C, aggR, astA, eae, ehly, iha, irp2, lpfA(O113), pet, pic, pilS, and shf. Sixteen strains presented aggregative adherence and/or the aatA sequence, which are characteristics of enteroaggregative E. coli (EAEC), one of the DEC pathotypes. in summary, certain UPEC strains may carry DEC virulence properties, mostly associated to the EAEC pathotype. This finding raises the possibility that at least some faecal EAEC strains might represent potential uropathogens. Alternatively, certain UPEC strains may have acquired EAEC properties, becoming a potential cause of diarrhoea.Universidade Federal de São Paulo, Escola Paulista Med, Dept Microbiol Immunol & Parasitol, BR-04023062 São Paulo, BrazilUniv Santiago de Compostela, Fac Vet, Dept Microbiol & Parasitol, Lab Referencia E Coli, Lugo, SpainUniversidade Federal de São Paulo, Lab Cent Hosp São Paulo, São Paulo, BrazilInst Butantan, Bacteriol Lab, São Paulo, BrazilUniversidade Federal de São Paulo, Escola Paulista Med, Dept Microbiol Immunol & Parasitol, BR-04023062 São Paulo, BrazilUniversidade Federal de São Paulo, Lab Cent Hosp São Paulo, São Paulo, BrazilWeb of Scienc
Antioxidant capacity of different cheeses: Affecting factors and prediction by near infrared spectroscopy
In this study, we analyzed antioxidant capacity of 224 cheese samples prepared using 16 varied mixtures of milk from cows, ewes, and goats, in 2 manufacturing seasons (winter and summer), and over 6 mo of ripening. Antioxidant capacity was evaluated using the spectrophotometric 2,2-azinobis(3-ethylenebenzothiazoline-6-sulfonic acid) (ABTS) method. Total antioxidant capacity was significantly correlated with season of manufacturing and time of ripening but not with animal species providing the milk. Moreover, statistically significant correlations between the total antioxidant capacity and retinol (r = 0.399), fat percentage (r = 0.308), protein percentage (r = 0.366), K (r = 0.385), Mg (r = 0.312), Na (r = 0.432), and P (0.272) were observed. We evaluated the use of near infrared spectroscopy technology, together with the use of a remote reflectance fiber-optic probe, to predict the antioxidant capacity of cheese samples. The model generated allowed us to predict antioxidant capacity in unknown cheeses of different compositions and ripening times.Junta de Castilla y León SA1390
Detection & identification of hazardous narcotics and new psychoactive substances using Fourier transform infrared spectroscopy (FTIR)
According to the latest World Drug Report, released by the United Nations Office on Drugs and Crime (UNODC), drug use is up 30% over the past decade and there are more drugs, and more types of drugs, than ever. Herein we use Fourier Transform Infrared Spectroscopy (FTIR) for the rapid ID of narcotics in a range of concentrations – from pure forms (as it is likely to be smuggled & transported) to street forms, often mixed with conventional cutting agents. Using FTIR, 75% of “street sample” narcotics were rapidly identified, and the effects of cutting agents on identification (ID) were also investigated. The limit of detection of MDMA was assessed, with a correct ID shown from 25% w/v. Concentration was correlated with Hit Quality Index, showing the capability of FTIR use in concentration estimation
COVID-19 risk stratification algorithms based on sTREM-1 and IL-6 in emergency department.
The coronavirus disease 2019 (COVID-19) pandemic has led to surges of patients presenting to emergency departments (EDs) and potentially overwhelming health systems.
We sought to assess the predictive accuracy of host biomarkers at clinical presentation to the ED for adverse outcome.
Prospective observational study of PCR-confirmed COVID-19 patients in the ED of a Swiss hospital. Concentrations of inflammatory and endothelial dysfunction biomarkers were determined at clinical presentation. We evaluated the accuracy of clinical signs and these biomarkers in predicting 30-day intubation/mortality, and oxygen requirement by calculating the area under the receiver-operating characteristic curve and by classification and regression tree analysis.
Of 76 included patients with COVID-19, 24 were outpatients or hospitalized without oxygen requirement, 35 hospitalized with oxygen requirement, and 17 intubated/died. We found that soluble triggering receptor expressed on myeloid cells had the best prognostic accuracy for 30-day intubation/mortality (area under the receiver-operating characteristic curve, 0.86; 95% CI, 0.77-0.95) and IL-6 measured at presentation to the ED had the best accuracy for 30-day oxygen requirement (area under the receiver-operating characteristic curve, 0.84; 95% CI, 0.74-0.94). An algorithm based on respiratory rate and sTREM-1 predicted 30-day intubation/mortality with 94% sensitivity and 0.1 negative likelihood ratio. An IL-6-based algorithm had 98% sensitivity and 0.04 negative likelihood ratio for 30-day oxygen requirement.
sTREM-1 and IL-6 concentrations in COVID-19 in the ED have good predictive accuracy for intubation/mortality and oxygen requirement. sTREM-1- and IL-6-based algorithms are highly sensitive to identify patients with adverse outcome and could serve as early triage tools
Neutrino Clustering in the Galaxy with a Global Monopole
In spherically symmetric, static spacetime, we show that only j=1/2 fermions
can satisfy both Einstein's field equation and Dirac's equation. It is also
shown that neutrinos are able to have effective masses and cluster in the
galactic halo when they are coupled to a global monopole situated at the
galactic core. Astronomical implications of the results are discussed.Comment: 8 pages, Revtex
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