PBP4: A New Perspective on Staphylococcus aureus β-Lactam Resistance.

β-lactam antibiotics are excellent drugs for treatment of staphylococcal infections, due to their superior efficacy and safety compared to other drugs. Effectiveness of β-lactams is severely compromised due to resistance, which is widespread among clinical strains of Staphylococcus aureus. β-lactams inhibit bacterial cells by binding to penicillin binding proteins (PBPs), which perform the penultimate steps of bacterial cell wall synthesis. Among PBPs of S. aureus, PBP2a has received the most attention for the past several decades due to its preeminent role in conferring both high-level and broad-spectrum resistance to the entire class of β-lactam drugs. Studies on PBP2a have thus unraveled incredible details of its mechanism of action. We have recently identified that an uncanonical, low molecular weight PBP of S. aureus, PBP4, can also provide high-level and broad-spectrum resistance to the entire class of β-lactam drugs at a level similar to that of PBP2a. The role of PBP4 has typically been considered not so important for β-lactam resistance of S. aureus, and as a result its mode of action remains largely unknown. In this article, we review our current knowledge of PBP4 mediating β-lactam resistance in S. aureus

Random-energy model in random fields

The random-energy model is studied in the presence of random fields. The problem is solved exactly both in the microcanonical ensemble, without recourse to the replica method, and in the canonical ensemble using the replica formalism. The phase diagrams for bimodal and Gaussian random fields are investigated in detail. In contrast to the Gaussian case, the bimodal random field may lead to a tricritical point and a first-order transition. An interesting feature of the phase diagram is the possibility of a first-order transition from paramagnetic to mixed phase.Comment: 18 pages, 5 figures (included

Can one reconstruct masked CMB sky?

The CMB maps obtained by observations always possess domains which have to be masked due to severe uncertainties with respect to the genuine CMB signal. Cosmological analyses ideally use full CMB maps in order to get e.g. the angular power spectrum. There are attempts to reconstruct the masked regions at least at low resolutions, i.e. at large angular scales, before a further analysis follows. In this paper, the quality of the reconstruction is investigated for the ILC (7yr) map as well as for 1000 CMB simulations of the LambdaCDM concordance model. The latter allows an error estimation for the reconstruction algorithm which reveals some drawbacks. The analysis points to errors of the order of a significant fraction of the mean temperature fluctuation of the CMB. The temperature 2-point correlation function C(theta) is evaluated for different reconstructed sky maps which leads to the conclusion that it is safest to compute it on the cut-sky

Seleção de primers RAPD para caracterização genética em Oenocarpus mapora.

A bacaby (Oenocarpus mapora) é uma palmeira produtora de frutos que produzem óleo excelente qualidade e refresco de alto valor nutricional. A seleção de primers RAPD foi realizada visando à análise de divergência genética entre acessos do Banco de Germoplasma da Embrapa Amazônia Oriental. Foram testados 106 primers RAPD em cinco genótipos de O. mapora. 65,1% dos primers foram polimórficos, os quais geraram 307 bandas, com 71,3% delas polimórficas. Dos primers testados, 24 foram selecionados para a análise de divergência genética, os quais apresentaram boa amplificação e considerável polimorfismo. Os primers selecionados foram: OPA-04, OPA-06, OPA-12, OPAB-01, OPAB-02, OPAB-11, OPAB-12, OPAB-19, OPAZ-04, OPAZ-11, OPAR-07, OPB-11, OPJ-12, OPM-07, OPN-11, OPO-03, OPO-12, OPO-16, OPU-01, OPU-06, OPU-16, OPU-17, OPS-13, OPS-15

A Limit on the Polarized Anomalous Microwave Emission of Lynds 1622

The dark cloud Lynds 1622 is one of a few specific sites in the Galaxy where, relative to observed free-free and vibrational dust emission, there is a clear excess of microwave emission. In order to constrain models for this microwave emission, and to better establish the contribution which it might make to ongoing and near-future microwave background polarization experiments, we have used the Green Bank Telescope to search for linear polarization at 9.65 Ghz towards Lynds 1622. We place a 95.4% upper limit of 88 micro-Kelvin (123 micro-Kelvin at 99.7 confidence) on the total linear polarization of this source averaged over a 1'.3 FWHM beam. Relative to the observed level of anomalous emission in Stokes I these limits correspond to fractional linear polarizations of 2.7% and 3.5%.Comment: replaced with version accepted by Ap

Utilização do sistema integrado de diagnose e recomendação (DRIS) na determinação do estado nutricional da pimenta-do-reino em Paragominas, PA.

bitstream/item/48883/1/Boletim-Pesquisa-191-CPATU.pd

Micorrizas arbusculares em sistemas agroflorestais na Amazônia.

A maioria dos solos da Amazônia apresenta acidez elevada e alta saturação com alumínio, o que limita os seus usos na agricultura regional. Uma alternativa eficiente para o uso dos solos é a utilização de microrganismos do solo visando um melhor aproveitamento dos nutrientes pelas plantas. Os fungos micorrízicos arbusculares (FMA) aumentam a capacidade da planta de absorver nutrientes do solo e água, favorecendo sua nutrição. Os Sistemas Agroflorestais têm por base se aproximar da estrutura e dinâmica de uma floresta natural. O objetivo deste trabalho foi avaliar a presença de micorrizas arbusculares na rizosfera de um Sistema Agroflorestal. Foram verificadas a ocorrência de esporos na rizosfera e a colonização radicular em espécies componentes de um Sistema Agroflorestal, em épocas distintas. O número de esporos nos solos rizosféricos das espécies variou de 89 a 329 esporos/50 gramas de solo. A colonização radicular por fungos micorrízicos arbusculares variou de 6,8 a 99,6% nas plantas do SAF e com alta concentração na época seca

Sistema para auxiliar o manejo de rebanhos leiteiros e a tomada de decisões.

Efeitos da globalização e da era da informação. Manejo dos rebanhos e registros de desempenho. Programas de seleção e gerência da informação. Proleite - Sistema da acompanhamento e avaliação de rebanhos leiteiros.bitstream/item/76672/1/CNPTIA-COM.TEC.-1-99.pd