17,804 research outputs found
Staircase Models from Affine Toda Field Theory
We propose a class of purely elastic scattering theories generalising the
staircase model of Al. B. Zamolodchikov, based on the affine Toda field
theories for simply-laced Lie algebras g=A,D,E at suitable complex values of
their coupling constants. Considering their Thermodynamic Bethe Ansatz
equations, we give analytic arguments in support of a conjectured
renormalisation group flow visiting the neighbourhood of each W_g minimal model
in turn.Comment: 22 pages, Saclay-Bologna preprint SPhT/92-065, DFUB-92-0
On the emergent Semantic Web and overlooked issues
The emergent Semantic Web, despite being in its infancy, has already received a lotof attention from academia and industry. This resulted in an abundance of prototype systems and discussion most of which are centred around the underlying infrastructure. However, when we critically review the work done to date we realise that there is little discussion with respect to the vision of the Semantic Web. In particular, there is an observed dearth of discussion on how to deliver knowledge sharing in an environment such as the Semantic Web in effective and efficient manners. There are a lot of overlooked issues, associated with agents and trust to hidden assumptions made with respect to knowledge representation and robust reasoning in a distributed environment. These issues could potentially hinder further development if not considered at the early stages of designing Semantic Web systems. In this perspectives paper, we aim to help engineers and practitioners of the Semantic Web by raising awareness of these issues
Avaliação do SLICS no tratamento das lesÔes da coluna cervical sub-axial
The SLICS (Sub-axial Cervical Spine Injury Classification System) was proposed to help in the decision-making of sub-axial cervical spine trauma (SCST), even though the literature assessing its safety and efficacy is scarce. Method: We compared a cohort series of patients surgically treated based on surgeon's preference with patients treated based on the SLICS. Results: From 2009-10, 12 patients were included. The SLICS score ranged from 2 to 9 points (mean of 5.5). Two patients had the SLICS < 4 points. From 2011-13, 28 patients were included. The SLICS score ranged from 4 to 9 points (mean of 6). There was no neurological deterioration in any group. Conclusion: After using the SLICS there was a decrease in the number of patients with less severe injuries that were treated surgically. This suggests that the SLICS can be helpful in differentiating mild from severe injuries, potentially improving the results of treatment.The SLICS (Sub-axial Cervical Spine Injury Classification System) was proposed to help in the decision-making of sub-axial cervical spine trauma (SCST), even though the literature assessing its safety and efficacy is scarce. Method: We compared a cohort s735445449sem informaçãosem informaçãoO SLICS (Sub-axial Cervical Spine Injury Classification System) foi proposto para auxĂlio na tomada de decisĂŁo no tratamento do traumatismo da coluna cervical sub-axial. Contudo, existem poucos trabalhos que avaliem sua segurança e eficĂĄcia. MĂ©todo: Rea
Lower on the totem pole : The influence of sense of control and trait anxiety on cortisol at lower hierarchical levels
Several studies have found that hierarchical position either increases or reduces physiological stress. The purpose of this study was to investigate the moderating effect of sense of control or trait anxiety on the relationship between hierarchical position and physiological stress. Using a multilevel mixed-effects regression, we hypothesized that sense of control or trait anxiety could be buffers (accelerants) in lowering (increasing) physiological stress for those higher (lower) in the hierarchy. We draw on a sample of 202 Portuguese executives. Our findings indicate that relative to top-level managers, those lower in the hierarchical position had a lower salivary cortisol. Considering the moderating effects of sense of control or trait anxiety, executives lower in the hierarchy who have a higher sense of control or report higher trait anxiety levels had higher cortisol levels. Sense of control or trait anxiety may aid in the understanding of more subtle associations between hierarchical position and physiological stress.info:eu-repo/semantics/publishedVersio
Prediction of sarcomere mutations in subclinical hypertrophic cardiomyopathy.
BACKGROUND: Sarcomere protein mutations in hypertrophic cardiomyopathy induce subtle cardiac structural changes before the development of left ventricular hypertrophy (LVH). We have proposed that myocardial crypts are part of this phenotype and independently associated with the presence of sarcomere gene mutations. We tested this hypothesis in genetic hypertrophic cardiomyopathy pre-LVH (genotype positive, LVH negative [G+LVH-]). METHODS AND RESULTS: A multicenter case-control study investigated crypts and 22 other cardiovascular magnetic resonance parameters in subclinical hypertrophic cardiomyopathy to determine their strength of association with sarcomere gene mutation carriage. The G+LVH- sample (n=73) was 29 ± 13 years old and 51% were men. Crypts were related to the presence of sarcomere mutations (for â„1 crypt, ÎČ=2.5; 95% confidence interval [CI], 0.5-4.4; P=0.014 and for â„2 crypts, ÎČ=3.0; 95% CI, 0.8-7.9; P=0.004). In combination with 3 other parameters: anterior mitral valve leaflet elongation (ÎČ=2.1; 95% CI, 1.7-3.1; P<0.001), abnormal LV apical trabeculae (ÎČ=1.6; 95% CI, 0.8-2.5; P<0.001), and smaller LV end-systolic volumes (ÎČ=1.4; 95% CI, 0.5-2.3; P=0.001), multiple crypts indicated the presence of sarcomere gene mutations with 80% accuracy and an area under the curve of 0.85 (95% CI, 0.8-0.9). In this G+LVH- population, cardiac myosin-binding protein C mutation carriers had twice the prevalence of crypts when compared with the other combined mutations (47 versus 23%; odds ratio, 2.9; 95% CI, 1.1-7.9; P=0.045). CONCLUSIONS: The subclinical hypertrophic cardiomyopathy phenotype measured by cardiovascular magnetic resonance in a multicenter environment and consisting of crypts (particularly multiple), anterior mitral valve leaflet elongation, abnormal trabeculae, and smaller LV systolic cavity is indicative of the presence of sarcomere gene mutations and highlights the need for further study
FarmacogenĂłmica da depressĂŁo
A saĂșde mental Ă© um problema real e atual a nĂvel global devido ao aumento da
sua incidĂȘncia e impacto na qualidade de vida da sociedade. Dentro deste grupo de
patologias insere-se a depressão, uma perturbação do humor, que neste momento afeta
mais de 322 milhÔes de pessoas no mundo em que 800 mil mortes anuais são devidas a
suicĂdios causados por este transtorno.
A depressão é uma doença mental que se relaciona com o estado de humor da
pessoa, causando uma perda de interesse ou prazer por atividades antes apreciadas. Esta
doença caminha para se tornar uma das principais causas de perda de anos saudåveis de
vida, portanto é importante a identificação de estratégias de prevenção e o diagnóstico
correto.
A escolha principal para o tratamento da depressĂŁo sĂŁo os antidepressivos que
atuam na sintomatologia da mesma. A resposta a esta terapĂȘutica vai variar de indivĂduo
para indivĂduo, podendo causar problemas de efeitos adversos, reaçÔes de toxicidade e de
resposta.
Assim, uma estratĂ©gia para melhorar esta terapĂȘutica Ă© a aplicação de estudos
farmacogenĂłmicos. A farmacogenĂłmica Ă© a ciĂȘncia que atravĂ©s da informação genĂ©tica
do indivĂduo ou de um certo tecido danificado (p.ex., tumor maligno) permite perceber
qual a dosagem e fĂĄrmaco mais indicado no tratamento de patologias para cada doente.
Permite, entĂŁo, adaptar melhor a terapĂȘutica Ă diversidade genĂ©tica da população de
pacientes que sofrem de depressĂŁo, isto Ă©, permite a implementação de uma âmedicina
personalizadaâ
Turbulent fluxes in atmospheric boundary layer of a semi-arid region of N-E Brazil
The preliminary results of the experiment âExperimento de Microfisica de Nuvens-EmfiNâ (Experiment of microphysics of clouds) conducted by Universidade Estadual de Ceara-UECE at Fortaleza, a semi-arid region of N-E Brazil, are presented. The mean kinematic fluxes of sensible heat and water vapor
of the surface boundary layer are estimated by the thermodynamic energy and water vapor conservation equations; and by the Monin-Obukhov similarity theory. The results of the two methods are in good agreement. It is shown that in the absence of sophisticated fast-response turbulence instrumentation and wind data the
conservations equations methods are better option for estimation of heat and water vapor fluxes. Further they are useful to study the turbulent fluxes in inhomogeneous
condition in time like early morning and late evening boundary layer transitions
Surface boundary layer characteristics over caatinga vegetation in tropical semiarid region of N-E Brazil
Some characteristic features of the atmospheric surface layer over
a tropical semiarid station Petrolina (9.9âŠS, 40.22âŠW, 365.5 m) in N-E Brazil, are
investigated, using data collected from a micrometeorological tower of 9 m height.
This study utilizes the wind, temperature, humidity and carbon dioxide (CO2) data
obtained for the month of July 2004. The diurnal variation of mean parameters
such as temperature, relative humidity, wind speed and CO2 are studied. Turbulent
statistics are computed using the eddy correlation technique, and are studied under
the framework of Monin-Obukhov similarity theory with results compared with other
experimental studies reported in the literature
Some aspects of the structure of the stratified atmospheric boundary layer of N-E Brazil
The preliminary results of an analysis based on the experiment âExperimento de Microfisica de NuvensâEmfiNâ (Experiment of Microphysics of Clouds), conducted by Universidade Estadual de CearaâUECE at Fortaleza (3.77 S
and 38.60 W), a semi-arid tropical region of N-E Brazil, are presented. The kinematic stresses are computed by the layer integration of the Planetary Boundary Layer(PBL) momentum equation forhor izontally homogeneous turbulence above the viscous sublayer condition and considering that the inertial acceleration terms could be neglected compared to the Coriolis force and pressure gradient force. The
computed stress profiles are in good agreement with the results reported in the literature
Protein farnesyltransferase and protein prenylation in Plasmodium falciparum
Comparison of the malaria parasite and mammalian protein prenyltransferases and their cellular substrates is important for establishing this enzyme as a target for developing antimalarial agents. Nineteen heptapeptides differing only in their carboxyl-terminal amino acid were tested as alternative substrates of partially purified Plasmodium falciparum protein farnesyltransferase. Only NRSCAIM and NRSCAIQ serve as substrates, with NRSCAIM being the best. Peptidomimetics, FTI-276 and GGTI-287, inhibit the transferase with IC50 values of 1 and 32 nm, respectively. Incubation of P. falciparum-infected erythrocytes with [H-3]farnesol labels 50- and 22-28-kDa proteins, whereas [H-3]geranylgeraniol labels only 22-28-kDa proteins. The 50-kDa protein is shown to be farnesylated, whereas the 22-28-kDa proteins are geranylgeranylated, irrespective of the labeling prenol. Protein labeling is inhibited more than 50% by either 5 mum FTI-277 or GGTI-298. The same concentration of inhibitors also inhibits parasite growth from the ring stage by 50%, decreases expression of prenylated proteins as measured with prenyl-specific antibody, and inhibits parasite differentiation beyond the trophozoite stage. Furthermore, differentiation specific prenylation of P. falciparum proteins is demonstrated. Protein labeling is detected predominantly during the trophozoite to schizont and schizont to ring transitions. These results demonstrate unique properties of protein prenylation in P. falciparum: a limited specificity of the farnesyltransferase for peptide substrates compared with mammalian enzymes, the ability to use farnesol to label both farnesyl and geranylgeranyl moieties on proteins, differentiation specific protein prenylation, and the ability of peptidomimetic prenyltransferase inhibitors to block parasite differentiation
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