Lateral strength of zero bond masonry walls subjected to wind loads

Masonry walls are usually laid with the individual masonry units along a course overlapping units in the course below. Commonly, the perpend joints in the course occur above the mid-points of the units below to form a ‘half-bond’ or above a third point to form a ‘third-bond’. The amount of this overlap has a profound influence on the strength of a wall supported on three or four sides, where lateral pressures from wind cause combined vertical and horizontal flexure. Where masonry units are laid with mortar joints, the torsional shear bond resistance between the mortar and overlapping units largely determines the horizontal flexural strength. If there is zero bond strength between units, then the horizontal flexural strength is derived from the frictional resistance to torsion on the overlapping bed-faces of the units. This thesis reports a theoretical and experimental investigation into the frictional properties of overlapping units when subjected to combinations of vertical and horizontal moments and vertical axial compression. These basic properties were used to develop a theory to predict the lateral strength of walls supported on two, three or four sides. A plastic theory of behaviour was confirmed by experiment. The theory was then used to determine maximum unbraced panel sizes for particular boundary conditions. Design charts were developed to determine temporary bracing requirements for panels during construction.

Estudo experimental de ligações entre paredes de alvenaria estrutural de blocos cerâmicos sujeitas a ações verticais

Pós-graduação em Engenharia Civil - FEIS

Estudo teórico e experimental das ligações diretas contra-fiadas entre paredes de blocos de concreto em escala real e reduzida 1:4

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Unusual 1H NMR chemical shifts support (His) Cɛ1—H⋅⋅⋅O⩵C H-bond: Proposal for reaction-driven ring flip mechanism in serine protease catalysis

13C-selective NMR, combined with inhibitor perturbation experiments, shows that the Cɛ1—H proton of the catalytic histidine in resting α-lytic protease and subtilisin BPN′ resonates, when protonated, at 9.22 ppm and 9.18 ppm, respectively, which is outside the normal range for such protons and ≈0.6 to 0.8 ppm further downfield than previously reported. They also show that the previous α-lytic protease assignments [Markley, J. L., Neves, D. E., Westler, W. M., Ibanez, I. B., Porubcan, M. A. & Baillargeon, M. W. (1980) Front. Protein Chem. 10, 31–61] were to signals from inactive or denatured protein. Simulations of linewidth vs. pH demonstrate that the true signal is more difficult to detect than corresponding signals from inactive derivatives, owing to higher imidazole pKa values and larger chemical shift differences between protonated and neutral forms. A compilation and analysis of available NMR data indicates that the true Cɛ1—H signals from other serine proteases are similarly displaced downfield, with past assignments to more upfield signals probably in error. The downfield displacement of these proton resonances is shown to be consistent with an H-bond involving the histidine Cɛ1—H as donor, confirming the original hypothesis of Derewenda et al. [Derewenda, Z. S., Derewenda, U. & Kobos, P. M. (1994) J. Mol. Biol. 241, 83–93], which was based on an analysis of literature x-ray crystal structures of serine hydrolases. The invariability of this H-bond among enzymes containing Asp-His-Ser triads indicates functional importance. Here, we propose that it enables a reaction-driven imidazole ring flip mechanism, overcoming a major dilemma inherent in all previous mechanisms, namely how these enzymes catalyze both the formation and productive breakdown of tetrahedral intermediates.

Advantage of the ether linkage between the positive charge and the cholesteryl skeleton in cholesterol-based amphiphiles as vectors for gene delivery

Twelve novel cationic cholesterol derivatives with different linkage types between the cationic headgroup and the cholesteryl backbone have been developed. These have been tested for their efficacies as gene transfer agents as mixtures with dioleoyl phosphatidylethanolamine (DOPE). A pronounced improvement in transfection efficiency was observed when the cationic center was linked to the steroid backbone using an ether type bond. Among these, cholest-5-en-3b-oxyethane-N, N,N-trimethylammonium bromide (2a) and cholest-5-en-3b-oxyethane-N, N-dimethyl-N-2-hydroxyethylammonium bromide (3d) showed transfection efficiencies considerably greater than commercially available reagents such as Lipofectin or Lipofectamine. To achieve transfection, 3d did not require DOPE. Increasing hydration at the headgroup level for both ester- and ether-linked amphiphiles resulted in progressive loss of transfection efficiency. Transfection efficiency was also greatly reduced when a 'disorder'-inducing chain like an oleyl (cis-9-octadecenyl) segment was added to these cholesteryl amphiphiles. Importantly, the transfection ability of 2a with DOPE in the presence of serum was significantly greater than for a commercially available reagent, Lipofectamine. This suggests that these novel cholesterol-based amphiphiles might prove promising in applications involving liposome-mediated gene transfection. This investigation demonstrates the importance of structural features at the molecular level for the design of cholesterol-based gene delivery reagents that would aid the development of newer, more efficient formulations based on this class of molecules.

Northern range extension, abundance and distribution of Pacific coastal Bottlenose doplhins (Tursiops truncatus gilli) in Monterey Bay, California

Pacific coastal bottlenose dolphins (Tursiops truncatus gilli) have apparently moved to Monterey Bay as a result of a shift north of their known range. Between 1983 and 1993, 417 sightings were reported off central California. Eighty-four boat-based surveys, between October 1990 and November 1993, resulted in the photo-identification of 68 uniquely marked individuals. School size ranged between 2 and 35 animals (mean = 16.60, S.D. = 7.72). Forty-three (63%) of the dolphins identified were previously photographed in the Southern California Bight before 1989. Jolly-Seber population estimates indicated an increase in the Monterey Bay population from 1990 to 1993. At least 13 of the photo-identified dolphins were present in Monterey Bay throughout the study period. All but two of the calculated coefficients of association were 0.35, indicating a strong bond among resident animals. The occurrence of an El Niño from January 1992 to the end of 1993 may have affected the number of animals present in the bay: mean school size was significantly greater during El Niño.

Agentes Comunitários de Saúde, formação e perfil profissional: o caso de Duque de Caxias, RJ

Este estudo teve como objetivo analisar o perfil de trabalho e descrever a formação profissional dos Agentes Comunitários de Saúde (ACS) no Município de Duque de Caxias. Trata-se de um estudo descritivo e de abordagem quantitativa e qualitativa, com base em uma perspectiva de triangulação de métodos. A pesquisa foi dividida em dois momentos distintos durante a coleta de dados. No primeiro, reuniram-se informações que configurassem todo o histórico de implementação do trabalho dos ACS, desde o surgimento das primeiras equipes. No segundo momento, aplicou-se um questionário aos 51 ACS que compõem o quadro funcional, sendo 23 de unidades da Estratégia Saúde da Família (ESF) e 28 da Equipe de Agentes Comunitários de Saúde (EACS). Foram também realizadas entrevistas individuais com oito participantes. Na análise dos dados, foi possível: a) construir a trajetória histórica dos ACS no Município, incluindo seu perfil sociodemográfico; b) mapear e descrever o perfil e condições de trabalho, a formação dos ACS, o interesse e as motivações quanto à profissão, as atividades de educação em saúde realizadas e o vínculo do ACS com o enfermeiro. O campo de pesquisa foi o município de Duque de Caxias, situado na Baixada Fluminense, no Estado do Rio de Janeiro. Os resultados mostram que a maioria dos participantes é do sexo feminino (94,1%), se encontrava na faixa etária entre 40-49 anos (43%), possui o segundo grau completo (72,5%); por outro lado, apenas 29,4% participam de alguma associação ou sindicato que represente a categoria, 84,3%, atuam em média há mais de sete anos, 84,3 % consideram o seu serviço gerador de estresse, 62,7% não tiveram acesso a algum curso/capacitação antes de serem inseridos na prática. Entre os motivos para atuar como um ACS, citam-se: ajudar a comunidade, estar perto dos filhos e trabalhar perto de casa; já entre as desvantagens do trabalho estão condições precárias de trabalho e baixo salário/vinculo trabalhista precário. Entre as atividades educativas mais realiza, as orientações individuais sobre doenças predominou com 94,1%. Entre os ACS que atuam na ESF, o enfermeiro se destacam, por serem os profissionais que mais o acompanham na prática da educação em saúde (33,3%), seguido pelo dentista (29,2%). Conclui-se que os agentes apresentam fragilidades em reconhecer as suas atribuições no desempenho de suas atividades. A formação recebida se apresenta fora da proposta de mudança de modelo. Uma formação ampliada que permita uma maior compreensão de sua inserção profissional dentro da sociedade e especificamente no campo da saúde poderia mediar o reconhecimento e identidade profissional dos ACS que participaram deste estudo. Esta pesquisa está vinculada ao Grupo de Pesquisa Configurações do Trabalho, Saúde dos Trabalhadores e Enfermagem e à Pesquisa O trabalho dos Agentes Comunitários de saúde do Estado do Rio de Janeiro: análise comparativa entre municípios e regiões.

Structural analysis of SNARE motifs from sea perch, Lateolabrax japonicus by computerized approaches

Three cDNA sequences encoding four SNARE (N-ethylmaleimide-sensitive fusion protein attachment protein receptors) motifs were cloned from sea perch, and the deduced peptide sequences were analyzed for structural prediction by using 14 different web servers and softwares. The "ionic layer" structure, the three dimensional extension and conformational characters of the SNARE 7S core complex by using bioinformatics approaches were compared respectively with those from mammalian X-ray crystallographic investigations. The result suggested that the formation and stabilization of fish SNARE core complex might be driven by hydrophobic association, hydrogen bond among R group of core amino acids and electrostatic attraction at molecular level. This revealed that the SNARE proteins interaction of the fish may share the same molecular mechanism with that of mammal, indicating the universality and solidity of SNARE core complex theory. This work is also an attempt to get the protein 3D structural information which appears to be similar to that obtained through X-ray crystallography, only by using computerized approaches. (C) 2007 Elsevier Ltd. All rights reserved.

Psychological bonds and their impact on behavioral loyalty in auditor-client relationships

Purpose – The purpose of this paper is to examine the effect of the psychological bond on behavioral loyalty (word-of-mouth, continuance and non-audit services) to audit firms providing services to companies listed on the Polish Stock Exchange. Design/methodology/approach – A model is proposed and tested using structural equation modeling with LISREL. Data were collected from top executives of companies listed on the Warsaw Stock Exchange. Findings – The psychological bond has a positive effect on word-of-mouth, continuance and non-audit services. Research limitations/implications – The current research is limited to the investigation of the psychological bond as an antecedent of behavioral loyalty in Poland. Future research should identify and assess other antecedents and replicate these across different countries. A longitudinal survey across different points in time might reveal more useful information about auditor-client relationships. Practical implications – Auditors need to consider ways in which they can develop the psychological bond with their clients. This bond is the basis for the client believing the audit firm is superior to others, which has been found to lead to behavioral loyalty in this study. In particular, management of the auditor brand and reputation, personal experience of the audit firm and alumni relations are discussed as ways of enhancing the psychological bond among client executives. Originality/value – This study is the first to examine the impact of the psychological bond on behavioral loyalty in auditor-client relationships.

Ativação da ligação c-h no metano por espécies MOm n+ (M = Nb, Fe; m = 0, 1; n = 0, 1, 2): estrutura eletrônica, mecanismo de reação e reatividade

The need for renewal and a more efficient use of energy resources has provided an increased interest in studies of methane activation processes in the gas phase by transition metal oxides. In this respect, the present work is an effort to assess , by means of a computational standpoint, the reactivity of NbOm n+ and FeOm n+ (m = 1, 2, n = 0, 1, 2) oxides in the activation process of the methane C-H bond, which corresponds to the first rate limiting step in the process of converting methane to methanol. These oxides are chosen, primarily, because the iron oxides are the most experimentally studied, and iron ions are more abundant in biological mediums. The main motive for choosing niobium oxides is the abundance of natural reserves of this mineral in Brazil (98%), especially in Minas Gerais. Initially, a thorough investigation was conducted, using different theoretical methods, to analyze the structural and electronic properties of the investigated oxides. Based on these results, the most reliable methodology was selected to investigate the activation process of the methane C-H bond by the series of iron and niobium oxides, considering all possible reaction mechanisms known to activate the C-H bond of alkanes. It is worth noting that, up to this moment and to our knowledge, there are no papers, in literature , investigating and comparing all the mechanisms considered in this work. I n general, the main results obtained show different catalytic tendencies and behaviors throughout the series of monoxides and dioxides of iron and niobium. An important and common result found in the two studies is that the increase in the load on the metal center and the addition of oxygen atoms to the metal, clearly favor the initial thermodynamics of the reaction, i.e., favor the approach of the metal center to methane, distorting its electron cloud and, thereby, decreasing its inertia. Comparing the two sets of oxides, we conclude that the iron oxides are the most efficient in activating the methane C-H bond. Among the iron oxides investigated, FeO + showed better kinetic and thermodynamic performance in the reaction with methane, while from the niobium oxides and ions NbO 2+ and NbO2 2+, showed better catalytic efficiency in the activation of the methane C-H bond.

O professor mediador de leitura na biblioteca escolar da rede municipal de Londrina: formação e atuação

Pós-graduação em Educação - FFC

Imaginação, devaneio e poeticidade em narrativas de Corpo de Baile

Pós-graduação em Estudos Literários - FCLAR

Nós, os degredados filhos de Eva: angústia religiosa e alteridade entre rezadeiras do terço

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Letteratura parascolastica e nazionalismo nella Prima Repubblica

In the early decades of Brazilian Republic, didactic literature played an important role in contributing to the «spirit of national integration», as José Veríssimo recommended. But, in addition to fighting the «parochialism» of different regions of the vast country, didactic literary works intended to combat the «foreign threat» represented by uncontrolled immigration and the economic and military imperialism. Brief analysis of Contos Pátrios (1894) and A Pátria Brasileira (1909), written by Olavo Bilac and Coelho Neto, and Porque Me Ufano do Meu País (1901), by earl of Afonso Celso, aims to reveal some of the resources used by the authors to elicit the feeling of brotherhood, solidarity and collective bond among Brazilian children, driving away threats that hung over the country. It also indicates that the interpretation of the national past, from which came the heroes, martyrs and leaders to be worshiped and imitated by children, radically opposed the monarchist Afonso Celso and the republicans Bilac and Coelho Neto.

Vibrational phase relaxation of O–H stretch in bulk water: Role of large amplitude angular jumps and negative cross-correlations among the forces on the O–H bond

The ultrafast vibrational phase relaxation of O–H stretch in bulk water is investigated in molecular dynamics simulations. The dephasing time (T2) of the O–H stretch in bulk water calculated from the frequency fluctuation time correlation function (Cω(t)) is in the range of 70–80 femtosecond (fs), which is comparable to the characteristic timescale obtained from the vibrational echo peak shift measurements using infrared photon echo [W.P. de Boeij, M.S. Pshenichnikov, D.A. Wiersma, Ann. Rev. Phys. Chem. 49 (1998) 99]. The ultrafast decay of Cω(t) is found to be responsible for the ultrashort T2 in bulk water. Careful analysis reveals the following two interesting reasons for the ultrafast decay of Cω(t). (A) The large amplitude angular jumps of water molecules (within 30–40 fs time duration) provide a large scale contribution to the mean square vibrational frequency fluctuation and gives rise to the rapid spectral diffusion on 100 fs time scale. (B) The projected force, due to all the atoms of the solvent molecules on the oxygen (FO(t)) and hydrogen (FH(t)) atom of the O–H bond exhibit a large negative cross-correlation (NCC). We further find that this NCC is partly responsible for a weak, non-Arrhenius temperature dependence of the dephasing rate.