Manual de Direito do Trabalho
Xavier, Bernardo da Gama Lobo
2011-01-01
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Fatty acids are an essential component of the
phospholipids of the inner and outer membranes of
Escherichia coli. The synthesis of both fatty acids and
phospholipids is regulated. Synthesis increases when
growth rate increases, is inhibited when starvation
occurs, and the fatty acid composition of the
membrane changes with growth temperature. Several
genes encoding enzymes involved in membrane
synthesis are located in the rpmF-plsX-fab operon. In
this operon, a gene encoding a phospholipid synthetic
gene of unknown function, plsX, lies just downstream
of the ribosomal protein gene rpmF and upstream of
five fatty acid biosynthetic genes, fabH, fabD, fabG,
acpP, and fabF. The operon is also complex;
transcription is initiated from at least eight promoters.
In addition, some transcripts produced by the operon
are cleaved by RNases while ...
In this thesis, detailed studies are presented into self-assembled, noncentrosymmetric, optically active films. Second harmonic generation (SHG) is used to measure the second order nonlinear optical susceptibility (?(2)) of ionically self-assembled monolayer (ISAM) thin films.
Conventional ISAM films are fabricated by alternately immersing a substrate into oppositely-charged polyelectrolyte solutions. The polyelectrolytes bind electrostatically to the oppositely-charged substrate, and thus reverse the charge of the substrate. The charge reversal limits the amount of adsorbed material and primes the substrate for the next layer. During the deposition of the nonlinear optical (NLO) active layer, the chromophores are attracted to the oppositely-charged surface, which results in net orientation of the chromophores. Some of the net orie...
Three strains of cyanobacteria (Anabaena PCC7120, A. variabilis and Nostoc commune), all
belonging to the family Nostocaceae, were found to be capable of modulating the production and
chemical composition of extracellular polysaccharides (EPS) in response to carbon and nitrogen
availability as well as pH. While the carbohydrate compositions of the glycans produced by the
different organisms were indicative of their recent evolutionary divergence, there were
measurable differences that were dependent upon growth conditions. The EPS resulting from
biofilm growth conditions was reduced in glucuronic acid levels in both Anabaena variabilis
ATCC 29413 and Anabaena PCC 7120. Under planktonic conditions, the glycan from A.
variabilis contained glucuronic acid when grown in nitrate-free BG-110 medium whereas A. PCC
7120 produced similar levels...
ABSTRACT
Light loss in single mode fiber optical switches is investigated. Loss due to reflection, aberration and fiber misalignment are evaluated. A simple model of image to fiber end face overlap for the fiber/lens system is developed. The intensity distribution of light in the fiber and imaging system is assumed to be gaussian. It was found that aberration is a major cause of loss and that fiber misalignment did not cause as much loss as expected. Loss due to reflection is assumed to be minimal due to the presence of anti-reflection coatings on the optical components.
This thesis completes the process of making architecture. It is a small project designed and built full scale. The act of realizing this work of architecture offered opportunities and limitations that do not exist within the confines of a desk project but, I believe, ultimately produced a stronger project. This is a piece of micro-architecture.
In order to create a project that is realizable for a thesis, I chose a small program: to design an exhibition structure that could be used outdoors to display and sell handmade items such as pottery. Since the use is temporary, the structure is designed to be portable, thus the assembly and disassembly of the building becomes a significant influence on the design. Beyond budget, weight and volume of the collapsed structure were significant design constraints.
This thesis is not just an explorat...
The objective of this study was to examine excess biological phosphorus removing bacterial populations and their substrate utilization mechanisms. This study was a smaller part of a overall study of temperature effects upon excess biological phosphorus removal.
Bacterial populations in both a continuous flow UCT (University of Cape Town) system and batch reactors were examined by direct counting using a well known staining procedure (Neisser staining), and a microscopic counting method developed by Cech and Hartman (1993). Substrate utilization was examined using PHB (Poly-β -Hydroxybutyrate - an internal substrate storage product) analysis by gas chromatography to supplement COD and acetate measurements.
The results showed that Poly-P bacterial counts were significantly greater at a 5 day sludge age compared to a 10 day sludge age. I...
Serial passaging of primary human fibroblasts leads to the formation of non-dividing senescent cells by a process termed replicative senescence. This tissue culture-based methodology is currently used as a model system to determine the underlying mechanisms of in vivo cellular aging and tumor suppression. Senescence is regarded as an alternative pathway to apoptosis, where cells undergo multiple changes in metabolic and cellular signaling pathways in order to prevent proliferation but still maintain a metabolically-active cell. Whether or not this model accurately reflects in vivo processes is presently controversial; however, replicative senescence is currently the most applicable model through which one can investigate the underlying causes of human cellular aging in the context of controlled environmental stress over time. This work...
This study assesses whether parentsâ educational background positively affects the retention and graduation of African-American students who attend Predominately White Institutions (PWI). Studies that have compared successful African-American students to unsuccessful African-American college students at PWI (Allen, 1985) have suggested that an important factor in understanding these differences in outcome is parentsâ educational background. College-educated parents may have clearer expectations for their childrenâs college experience and may have instilled different cultural or socialization messages in their children. Those messages could include Historical/Cultural, Black Identity/Self-Concept, Maladaptive, and Residual messages. These children may enter college with clearer ideas of college norms and expectations, and may have fewe...
