Shear deformation at 29% solid during solidification of magnesium alloy AZ91 and aluminium alloy A356

Partially solid commercial Al-Si and Mg-Al alloys have been deformed in shear during solidification using vane rheometry. The dendritic mush was deformed for a short period at 29% solid and allowed to cool naturally after deformation. Both alloys exhibited yield point behaviour and deformation was highly localised at the surface of maximum shear stress. The short period of deformation was found to have a distinct impact on the as-cast microstructure leading to fragmented dendrites in the deformation region of both alloys. In the case of the Mg-Al alloy, a concentrated region of interdendritic porosity was also observed in the deformation region. Concentrated porosity was not observed in the Al-Si alloy. (c) 2005 Elsevier B.V. All rights reserved.

Comprehensive study of surface chemistry of MCM-41 using Si-29 CP/MAS NMR, FTIR, pyridine-TPD, and TGA

A comprehensive study was conducted on mesoporous MCM-41. Spectroscopic examinations demonstrated that three types of silanol groups, i.e., single, (SiO)(3)Si-OH, hydrogen-bonded, (SiO)(3)Si-OH-OH-Si(SiO)(3), and geminal, (SiO)(2)Si(OH)(2), can be observed. The number of silanol groups/nm(2), alpha(OH), as determined by NMR, varies between 2.5 and 3.0 depending on the template-removal methods. All these silanol groups were found to be the active sites for adsorption of pyridine with desorption energies of 91.4 and 52.2 kJ mol(-1), respectively. However, only free silanol groups (involving single and geminal silanols) are highly accessible to the silylating agent, chlorotrimethylsilane. Silylation can modify both the physical and chemical properties of MCM-41.

Test-retest reliability of isokinetic strength and endurance tests in patients with intermittent claudication

The objective was to determine the reliability of isokinetic strength and endurance testing in the ankle joints of patients with intermittent claudication. Twenty-three patients with peripheral artery disease (PAD) and symptoms of intermittent claudication participated in the study. Isokinetic strength and endurance testing of the ankle joint were performed in symptomatic and asymptomatic legs on 3 separate days. Intraclass coefficient correlation of peak torque (PT) and total work (TW) ranged from 0.77 to 0.92 and 0.89 to 0.96, respectively. PT and TW increased significantly and similarly in both legs from day 1 to day 2 (PT: +42 +/- 84% in the symptomatic leg and +33 +/- 51% in the asymptomatic leg, p < 0.05;TW: +38 +/- 26% in the symptomatic leg and +26 +/- 50% in the asymptomatic leg, p < 0.05). In conclusion, isokinetic strength and endurance testing in the ankle joints of patients with PAD presents reliability coefficients ranging from 0.77 to 0.96. However, strength and endurance increased between the first and the other test sessions performed on separate days, suggesting that two test sessions are necessary for the accurate evaluation of strength and endurance in patients with PAD.

Efficacy of Profile .04 taper series 29 in removing filling materials during root canal retreatment-an in vitro study

Objective. The aim of this study was to compare Profile .04 taper series 29 instruments and hand files for gutta-percha removal. Study design. Twenty maxillary central incisors with a single straight canal were instrumented and filled. The teeth were divided into 2 groups of 10 specimens each, according to gutta-percha removal techniques: Group 1- Profile series 29 and Group 2- hand files and solvent. The amount of time for gutta-percha removal and the number of fractured instruments were evaluated. Radiographs were taken and the teeth were grooved longitudinally and split. The area of residual debris was measured using computer software. Results. The time for filling material removal was significantly shorter when Profile series 29 was used (P = .00). Regarding cleanliness, there were no statistical differences in the teeth halves evaluations (P = .05). Hand instruments cleaned the canals significantly better than Profiles, in the radiographic analysis considering the whole canal. Overall, the radiographic analysis showed a smaller percentage of residual debris than the teeth halves analysis. Conclusion. The Profile series 29 instruments proved to be faster than hand instruments in removing root filling materials; however, hand instruments yielded better root canal cleanliness. Some residual debris was not visualized by radiographs. (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2009; 108: e46-e50)

Inhibition of proliferation of HT-29 colon adenocarcinorna cells by carboxylate NSAIDs and their acyl glucuronides

Many nonsteroidal anti-inflammatory drugs (NSAIDs) which have antiproliferative activity in colon cancer cells are carboxylate compounds forming acyl glucuronide metabolites. Acyl glucuronides are potentially reactive, able to hydrolyse, rearrange into isomers, and covalently modify proteins under physiological conditions. This study investigated whether the acyl glucuronides (and isomers) of the carboxylate NSAIDs diflunisal, zomepirac and diclofenac had antiproliferative activity on human adenocarcinoma. HT-29 cells in culture. Included as controls were the carboxylate NSAIDs themselves, the non-carboxylate NSAID piroxicam, and the carboxylate non-NSAID valproate, as well as its acyl glucuronide and isomers. The compounds were incubated at 1-3000 muM with HT-29 cells for 24 hr, with [H-3]-thymidine added for an additional 2 hr incubation. IC50 values were calculated from the concentration-inhibition response curves for thymidine uptake. The four NSAIDs inhibited thymidine uptake, with IC50 values about 200-500 muM. All of the NSAID acyl glucuronides (and isomers, tested in the case of diflunisal) showed antiproliferative activity broadly comparable to the parent drugs. This activity may stem from direct uptake of intact glucuronide/isomers followed by covalent modification of proteins critical in the cell replication process. However, hydrolysis during incubation and cellular uptake of liberated parent NSAID will play a role. In HT-29 cells incubated with zomepirac, covalently modified proteins in cytosol were detected by immunoblotting with a zomepirac antibody, suggesting that HT-29 cells do have the capacity to glucuronidate zomepirac. The anti-epileptic drug valproate had no effect on inhibition of thymidine uptake, though, surprisingly, its acyl glucuronide and isomers were active. The reasons for this are unclear at present. (C) 2001 Elsevier Science Inc. All rights reserved.

Effects of high-dose etidronate treatment on microdamage accumulation and biomechanical properties in beagle bone before occurrence of spontaneous fractures

We recently demonstrated that suppressed bone remodeling allows microdamage to accumulate and causes reductions in some mechanical properties. However, in our previous study, I year treatment with high-dose etidronate (EHDP) did not increase microdamage accumulation in most skeletal sites of dogs in spite of complete remodeling suppression and the occurrence of spontaneous fractures of ribs and/or thoracic spinous processes. This study evaluates the effects of EHDP on microdamage accumulation and biomechanical properties before fractures occur. Thirty-six female beagles, 1-2 years old, were treated daily for 7 months with subcutaneous injections of saline vehicle (CNT) or EHDP at 0.5 (E-low) or 5 mg/kg per day (E-high). After killing, bone mineral measurement, histomorphometry, microdamage analysis, and biomechanical testing were performed. EHDP treatment suppressed intracortical and trabecular remodeling by 60%-75% at the lower dose, and by 100% at the higher dose. Osteoid accumulation caused by a mineralization deficit occurred only in the E-high group, and this led to a reduction of mineralized bone mass. Microdamage accumulation increased significantly by two- to fivefold in the rib, lumbar vertebra, ilium, and thoracic spinous process in E-low, and by twofold in the lumbar vertebra and ilium in E-high. However, no significant increase in damage accumulation was observed in ribs or thoracic spinous processes in E-high where fractures occur following 12 months of treatment. Mechanical properties of lumbar vertebrae and thoracic spinous processes were reduced significantly in both E-low and E-high. These findings suggest that suppression of bone remodeling by EHDP allows microdamage accumulation, but that osteoid accumulation reduces production of microdamage. (Bone 29:271-278; 2001) (C) 2001 by Elsevier Science Inc. All rights reserved.

A cassette ligation strategy with thioether replacement of three Gly-Gly peptide bonds: Total chemical synthesis of the 101 residue protein early pregnancy factor [psi(CH2S)(28-29,56-57,76-77)]

The 101 residue protein early pregnancy factor (EPF), also known as human chaperonin 10, was synthesized from four functionalized, but unprotected, peptide segments by a sequential thioether ligation strategy. The approach exploits the differential reactivity of a peptide-NHCH2CH2SH thiolate with XCH2CO-peptides, where X = Cl or I/Br. Initial model studies with short functionalized (but unprotected) peptides showed a significantly faster reaction of a peptide-NHCH2CH2SH thiolate with a BrCH2CO-peptide than with a CICH2CO-peptide, where thiolate displacement of the halide leads to chemoselective formation of a thioether surrogate for the Gly-Gly peptide bond. This rate difference was used as the basis of a novel sequential ligation approach to the synthesis of large polypeptide chains. Thus, ligation of a model bifunctional N-alpha-chloroacetyl, C-terminal thiolated peptide with a second N-alpha-bromoacetyl peptide demonstrated chemoselective bromide displacement by the thiol group. Further investigations showed that the relatively unreactive N-alpha-chloroacetyl peptides could be activated by halide exchange using saturated KI solutions to yield the highly reactive No-iodoacetyl peptides. These findings were used to formulate a sequential thioether ligation strategy for the synthesis of EPF, a 101 amino acid protein containing three Gly-Gly sites approximately equidistantly spaced within the peptide chain. Four peptide segments or cassettes comprising the EPF protein sequence (BrAc-[EPF 78-101] 12, ClAc-[EPF 58-75]-[NHCH2CH2SH] 13, ClAc-[EPF 30-55]-[NHCH2CH2SH] 14, and Ac-[EPF 1-27]-[NHCH2CH2SH] 15) of EPF were synthesized in high yield and purity using Boc SPPS chemistry. In the stepwise sequential ligation strategy, reaction of peptides 12 and 13 was followed by conversion of the N-terminal chloroacetyl functional group to an iodoacetyl, thus activating the product peptide for further ligation with peptide 14. The process of ligation followed by iodoacetyl activation was repeated to yield an analogue of EPF (EPF psi(CH2S)(28-29,56-57,76-77)) 19 in 19% overall yield.

Texto para discuss??o 29: reforma da previd??ncia: negocia????es entre os Poderes Legislativo e Executivo

Com o intuito de analisar as rela????es Legislativo- Executivo a partir do exemplo da reforma previdenci??ria, este artigo se prop??e a testar essa nova tese sobre o sistema pol??tico, bem como estabelecer, ou reconstituir, padr??es de negocia????o entre os poderes Legislativo e Executivo. Sabe-se que uma teoria nas ci??ncias sociais n??o ?? constru??da ou falseada apenas pelo estudo de um exemplo. Todavia, sabe-se tamb??m que somente uma an??lise espec??fica e qualitativa ?? capaz de salientar aspectos muitas vezes despercebidos por um estudo baseado em dados agregados, al??m de possibilitar novos estudos que atrav??s da acumula????o podem, talvez, reconstruir toda uma teoria. Este trabalho est?? dividido em quatro se????es, seguidas de uma conclus??o. A primeira se????o recupera algumas proposi????es te??ricas sobre o sistema pol??tico, focalizando mais propriamente a quest??o da governabilidade. A segunda prende-se ao debate recente em torno das rela????es Executivo-Legislativo. A terceira caracteriza teoricamente a reforma da previd??ncia. E, por fim, a quarta se????o analisa empiricamente a sua tramita????o no Congresso Nacional

Portaria n?? 158, de 29 de agosto de 2012: constitui a Comiss??o de Apoio ?? Gest??o das A????es de Capacita????o em Idiomas dos Servidores da ENAP

A Comiss??o de Apoio ?? Gest??o das A????es de Capacita????o em Idiomas dos Servidores da ENAP, institu??da pela Portaria n?? 18, de 15 de fevereiro de 2008, tem tido atualiza????es a cada ano, sendo a composi????o vigente objeto da Portaria n?? 158, de 29 de agosto de 2012. O objetivo desta Comiss??o est?? associado ao Programa de Capacita????o em Idiomas na ENAP por meio do qual a Escola financia bolsas de estudos em escolas de idiomas em Bras??lia nas l??nguas inglesa, francesa e espanhola.

Avaliação dos limiares de audibilidade das altas freqüências em indivíduos entre 18 e 29 anos sem queixas otológicas

Estudos recentes que avaliaram os limiares auditivos em altas freqüências trouxeram novas perspectivas à investigação de danos auditivos. Contudo, as pesquisas desenvolvidas ainda não estabeleceram um consenso para os padrões de normalidade dos limiares de audição nessas freqüências. OBJETIVO: Analisar os resultados dos limiares de audibilidade das altas freqüências, em nível de audição, de indivíduos entre 18 e 29 anos sem queixas otológicas. FORMA DE ESTUDO: Tipo seccional transversal. MATERIAL E MÉTODOS: Foram realizadas 60 audiometrias convencionais, sendo 51 exames com resultados normais, em indivíduos entre 18 e 29 anos. Esses indivíduos foram submetidos à audiometria de altas freqüências utilizando o aparelho AMPLAID 460 e fones de orelha Sennheiser HD 520 II, sendo os limiares obtidos em dBNA. RESULTADOS: Observou-se não existir diferença significativa nos limiares de audibilidade entre o sexo masculino e feminino. Foram obtidos os limiares de audição em dBNA nas altas freqüências para indivíduos sem queixas otológicas, entre 18 e 29 anos. CONCLUSÃO: Sugeriu-se que esses dados poderiam ser utilizados como referência de normalidade para estudos posteriores com equipamento de mesmo padrão, que tivessem como objetivo avaliar alterações auditivas apresentadas em indivíduos jovens.

Novos rumos do direito contabilístico: confronto entre a reforma espanhola e o SNC português

Jornadas de Contabilidade e Fiscalidade promovidas pelo Instituto Superior de Contabilidade e Administração do Porto, em Abril de 2009

A promoção/progressão em 2008 de Assistente do 1º triénio a Assistente do 2º triénio (ECPDESP) e a aplicabilidade ou não das Leis nºs 43/2005, de 29.08 e 53-C/2006, de 29.12

Trabalho de natureza profissional para a atribuição do Título de Especialista do Instituto Politécnico do Porto, na área de Direito, defendido a 11-01-2013.