1,807 research outputs found
Inoculação de bactérias fixadoras de nitrogênio em arroz de sequeiro (Oryza sativa): respostas fisiológicas em estudos in vitro.
Este estudo determinou as respostas fisiológicas de 10 variedades de arroz de sequeiro (Oryza sativa L.) inoculação utilizando bactérias fixadoras de nitrogênio em ensaios in vitro
Experimentally exploring compressed sensing quantum tomography
In the light of the progress in quantum technologies, the task of verifying
the correct functioning of processes and obtaining accurate tomographic
information about quantum states becomes increasingly important. Compressed
sensing, a machinery derived from the theory of signal processing, has emerged
as a feasible tool to perform robust and significantly more resource-economical
quantum state tomography for intermediate-sized quantum systems. In this work,
we provide a comprehensive analysis of compressed sensing tomography in the
regime in which tomographically complete data is available with reliable
statistics from experimental observations of a multi-mode photonic
architecture. Due to the fact that the data is known with high statistical
significance, we are in a position to systematically explore the quality of
reconstruction depending on the number of employed measurement settings,
randomly selected from the complete set of data, and on different model
assumptions. We present and test a complete prescription to perform efficient
compressed sensing and are able to reliably use notions of model selection and
cross-validation to account for experimental imperfections and finite counting
statistics. Thus, we establish compressed sensing as an effective tool for
quantum state tomography, specifically suited for photonic systems.Comment: 12 pages, 5 figure
Scheme Independence of
We work with two general factorization schemes in order to explore the
consequences of imposing scheme independence on . We see that
although the light quark sector is indifferent to the choice of a particular
scheme, the extension of the calculations to the heavy quark sector indicates
that a scheme like the is preferable.Comment: 11 pages, 2 figures. To appear in the Brief Reports of Phys. Rev.
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Exchange-correlation energy densities for two-dimensional systems from quantum dot ground-states
In this paper we present a new approach how to extract polarization-dependent
exchange-correlation energy densities for two-dimensional systems from
reference densities and energies of quantum dots provided by exact
diagonalization. Compared with results from literature we find systematic
corrections for all polarizations in the regime of high densities.Comment: 7 figures. submitted to Phys. Rev.
Overfeeding, Autonomic Regulation and Metabolic Consequences
The autonomic nervous system plays an important role in the regulation of body processes in health and disease. Overfeeding and obesity (a disproportional increase of the fat mass of the body) are often accompanied by alterations in both sympathetic and parasympathetic autonomic functions. The overfeeding-induced changes in autonomic outflow occur with typical symptoms such as adiposity and hyperinsulinemia. There might be a causal relationship between autonomic disturbances and the consequences of overfeeding and obesity. Therefore studies were designed to investigate autonomic functioning in experimentally and genetically hyperphagic rats. Special emphasis was given to the processes that are involved in the regulation of peripheral energy substrate homeostasis. The data revealed that overfeeding is accompanied by increased parasympathetic outflow. Typical indices of vagal activity (such as the cephalic insulin release during food ingestion) were increased in all our rat models for hyperphagia. Overfeeding was also accompanied by increased sympathetic tone, reflected by enhanced baseline plasma norepinephrine (NE) levels in both VMH-lesioned animals and rats rendered obese by hyperalimentation. Plasma levels of NE during exercise were, however, reduced in these two groups of animals. This diminished increase in the exercise-induced NE outflow could be normalized by prior food deprivation. It was concluded from these experiments that overfeeding is associated with increased parasympathetic and sympathetic tone. In models for hyperphagia that display a continuously elevated nutrient intake such as the VMH-lesioned and the overfed rat, this increased sympathetic tone was accompanied by a diminished NE response to exercise. This attenuated outflow of NE was directly related to the size of the fat reserves, indicating that the feedback mechanism from the periphery to the central nervous system is altered in the overfed state.
Statins inhibit C-reactive protein-induced chemokine secretion, ICAM-1 upregulation and chemotaxis in adherent human monocytes
Objectives. We have recently shown that CRP induces chemokine secretion and adhesion molecule up-regulation in human primary monocytes cultured in adherence. Given the increasing evidence on direct immunomodulatory properties of statins, we investigated their possible anti-inflammatory role on CRP-treated human monocytes. Methods. Monocytes were isolated by Ficoll-Percoll gradients and cultured in adherence to polystyrene. Chemokine secretion and adhesion molecule expression were detected by ELISA and flow cytometry. Migration assays were performed in modified Boyden chambers. Intracellular kinase activation was assessed by western blot. Results. Treatment with simvastatin or atorvastatin decreased CRP-induced release of CCL2, CCL3 and CCL4. In addition, both statins reduced CRP-induced intercellular adhesion molecule (ICAM-1) up-regulation, but had no effects on CD11b and CD18. Treatments with 1 μM simvastatin or atorvastatin significantly inhibited monocyte migration in response to CRP. CD32 and CD64 (CRP receptors) expression on monocytes was not affected by statins. Statin-induced inhibition of CRP-mediated chemokine secretion, ICAM-1 up-regulation and migration occurred through the inhibition of extracellular signal-regulated kinase (ERK) 1/2. Treatment with l-mevalonate or farnesylpyrophosphate, but not geranylgeranyl-pyrophosphate reversed the statin-induced effect on CRP-mediated functions and ERK 1/2 phosphorylation, confirming that statins blocked CRP-induced ERK 1/2 phosphorylation through the inhibition of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase. Conclusions. Statins inhibited CRP-induced chemokine secretion, ICAM-1 up-regulation and migration in human adherent monocytes, through the inhibition of HMG-CoA reductase-ERK 1/2 pathway. This pathway could represent a very promising target to reduce CRP-induced activities in monocyte-mediated diseases, such as atherosclerosis or R
Development and feasibility of a telemedicine tool for patients with recurrent urinary tract infection:myRUTIcoach
INTRODUCTION AND HYPOTHESIS: Patients with recurrent urinary tract infection (rUTI) have limited knowledge of preventive strategies to lower the risk of UTI. We aimed to develop and test the feasibility of an eHealth system for women with rUTI, named myRUTIcoach, and explored the facilitators and barriers related to its adoption.METHODS: We developed myRUTIcoach in a structured iterative process and tested its feasibility among 25 women with rUTI over 2 months. Subsequent questionnaires covered satisfaction, accessibility, and experiences with myRUTIcoach. A random selection of participants and relevant stakeholders took part in semi-structured interviews to explore adoption. Data were analyzed and elaborated using inductive and deductive approaches using the Non-adoption, Abandonment, Spread, Scale-up, and Sustainability (NASSS) framework.RESULTS: MyRUTIcoach was not only widely accepted but also facilitated communication with health care professionals (HCPs) and contributed to greater knowledge of rUTI. Women graded the system a mean of 8.0 (±0.6) out of 10, with 89% stating that they would recommend it to others. Patients indicated that self-management skills were the major facilitators and barriers related to adoption, whereas HCPs stated that the disconnect between myRUTIcoach and electronic health care records (EHRs) was the major barrier.CONCLUSIONS: This research describes the development and testing of myRUTIcoach for women with rUTI. Patients and HCPs reported high satisfaction and compliance with myRUTIcoach. However, adoption by the intended users is complex and influenced by all examined domains of the NASSS framework. We have already improved linkage to EHRs, but further optimization to meet patient needs may improve the effectiveness of this self-management tool for rUTI.</p
Diffusion Monte Carlo study of circular quantum dots
We present ground and excited state energies obtained from Diffusion Monte
Carlo (DMC) calculations, using accurate multiconfiguration wave functions, for
electrons () confined to a circular quantum dot. We analyze the
electron-electron pair correlation functions and compare the density and
correlation energies to the predictions of local spin density approximation
theory (LSDA). The DMC estimated change in electrochemical potential as
function of the number of electrons in the dot is compared to that from LSDA
and Hartree-Fock (HF) calculations.Comment: 7 pages, 4 eps figures. To be published in Phys. Rev. B, September
15th 2000. See erratum cond-mat/030571
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