Abstract In this work, the influence of uniaxial and biaxial partial edge loads on buckling and vibration characteristics of stiffened laminated plates is examined by using finite element method. As the initial pre-buckling stress distributions within an element are highly non-uniform in nature for a given loading and edge conditions, the critical loads are evaluated by dynamic approach. Towards this, a nine-node heterosis plate element and a compatible three-node beam element are developed by employing the effect of shear deformation for both the plate and the stiffeners respectively. In the structural modeling, the plate and the stiffener elements are treated separately, and then the displacement compatibility is maintained between them by using a transformation matrix. Effect of different parameters such as loaded edge width, position of loads, boundary conditions, ply-orientations and stiffener factors are considered in this study. Buckling results show that the uniaxial loaded stiffened plate with around (+30º/-30º)2 layup can withstand higher load irrespective of boundary conditions and loading patterns, whereas the maximum load resisting layup for the bi-axially loaded stiffened plate is purely dependent on edge conditions and loading patterns.

AbstractA novel Normal and Shear Deformation Theory (NSDT) for analysis of laminated composite and sandwich beams, taking into account shear deformation as well as normal deformation, is developed. The paper investigates flexural behaviors of thick laminated and sandwich beams under plane stress conditions using NSDT. A generalized displacement-based refined formulation is elucidated with inclusion of various warping functions in terms of thickness coordinates to represent shear and normal deformation effects. These effects become pronounced in thick laminated beams and particularly in sandwich beams with transversely flexible core. Present formulation satisfies the shear stress free surface conditions at the top and bottom surfaces of the beam with realistic through-the-thickness variation of transverse shear stresses. The results obtained are compared with higher order theories available in literature. It is observed that NSDT predicts displacement and stresses accurately compared to other higher order theories.

Cerâmicas de titanato de bário e estrôncio (TBS) (Ba0,6Sr0,4)TiO3 foram sintetizadas por sinterização do estado sólido usando carbonato de bário, carbonato de estrôncio e rutilo como materiais precursores. As amostras foram dopadas com diferentes proporções de óxido de níquel. Diferentes fases presentes nas amostras sinterizadas foram determinadas por difração de raios X e a distribuição de diferentes fases na microestrutura foi avaliada por microscopia eletrônica de varredura. Foi observado que as propriedades dielétricas do TBS foram modificadas significativamente com a dopagem do óxido de níquel. Essas cerâmicas são promissoras para aplicação em dispositivos.

Barium strontium titanate (BST) ceramics (Ba0.6Sr0.4)TiO3 were synthesized by solid state sintering using barium carbonate, strontium carbonate and rutile as the precursor materials. The samples were doped with nickel oxide in different proportions. Different phases present in the sintered samples were determined from X-ray diffraction investigation and the distribution of different phases in the microstructure was assessed from scanning electron microscopy study. It was observed that the dielectric properties of BST were modified significantly with nickel oxide doping. These ceramics held promise for applications in tuned circuits.

In the present investigation a novel series of N-(phenyl) chalconyl anthranilic acids containing pyrazolines (4a-j), tetra-hydropyrimidines (4k-o), tetrahydrothiopyrimidines (4p-t) and 2-phenylquinazolin-4(3H)-ones containing pyrazolines (8a-f), isoxazolines (8g-l), tetrahydropyrimidines (8m-r) and tetrahydrothiopyrimidines (8s-x) were synthesized and characterized by elemental analysis, FT-IR, ¹H NMR and mass spectroscopy. The title compounds (4a-t) and (8a-x) were investigated for their analgesic, anti-inflammatory, antimicrobial and in vitro protein denaturation activities. Compounds 4j and 8x were identified as lead compounds with optimum analgesic, anti-inflammatory and antimicrobial activities.

O tratamento de 3-amino-2-metilquinazolina/6-bromo-2-metilquinazolina-4(3H)-onas, 2a,b, com 2,3-indolinediona na presença de traços de ácido acético glacial forneceu 3-{(2'-oxo-1',2'-di-hidroindol-3'-ilideno)amino} -2-metilquinazolina/6-bromo-2-metilquinazolina-4-(3H)-onas, 3a,b, as quais foram condensadas com várias aminas secundárias e formaldeído em etanol para originar compostos do tipo 3-{(1'-alquil/arilaminometil-2'-oxo-1',2'-di-hidroindol-3'-ilideno)amino} -2-metil-6-quinazolin-4-(3H)-onas, 4a1-6 e 4b1-6.Os compostos sintetizados foram caracterizados por análise elementar, espectroscopia no infravermelho, RMN ¹H e espectrometria de massas. Adicionalmente, foram investigadas suas atividades antimicrobiana, analgésica, anti-inflamatória e anti-helmíntica. Os resultados das atividades biológicas revelaram que os compostos 4a3, 4a4 e 4b6 exibiram atividades analgésica e anti-inflamatória significativas. Os compostos 4b5 e 4b6 apresentaram atividade anti-helmíntica, quando testados frente a Pheretima posthuma.

The 3-amino-2-methylquinazoline/6-bromo-2-methylquinazoline-4(3H)-ones, 2a,b, on treatment with 2,3-indolinedione in the presence of traces of glacial acetic acid yielded 3-{(2'-oxo-1',2'-dihydroindole-3'-ylidene)amino} -2-methylquinazolin/6-bromo-2-methylquinazolin-4-(3H)-ones, 3a,b, which on condensation with various secondary amines and formaldehyde in ethanol afforded title compounds 3-{(1'-alkyl/arylaminomethyl-2'-oxo-1',2'-dihydroindole-3'-ylidene)amino} -2-methyl-6-quinazolin-4-(3H)-ones, 4a1-6 and 4b1-6. C, H, N analysis, infrared spectroscopy, ¹H NMR, and mass spectroscopy allowed the identification of the synthesized compounds, which were investigated for their antimicrobial, analgesic, anti-inflammatory and antihelmintic activities. The results of the biological activities revealed that the compounds 4a3, 4a4 and 4b6 exhibited significant analgesic and anti-inflammatory activities. Compounds 4b5 and 4b6 showed antihelmintic activity when tested against Pheretima posthuma.

OBJETIVO: A valva aórtica bicúspide (VAB) está associada a maior prevalência de ectasia anulo-aórtica, aneurisma e dissecção da aorta ascendente. Este estudo investigou a quantidade de fibrilina-1 e elastina nos grandes vasos de portadores de VAB. MÉTODO:Amostras de tecidos foram colhidas da aorta ascendente e tronco da artéria pulmonar de 22 portadores de VAB e 16 portadores de valva aórtica tricúspide (VAT) submetidos a cirurgia cardíaca, incluindo seis portadores de valva aórtica normal, provenientes do programa de transplante. Imunofluorescência indireta e análise computadorizada de imagens foram utilizadas para quantificação das proteínas na camada média dos vasos, expressas como densidade óptica integrada média (DOI). RESULTADOS: Na aorta, a DOI específica para fibrilina-1 foi 15 ± 8 no grupo bicúspide e 24 ± 7 no grupo tricúspide (p=0,001). Na artéria pulmonar, a DOI específica para fibrilina-1 foi 18 ± 10 no grupo bicúspide e 25 ± 9 no grupo tricúspide (p=0,07). A DOI específica para elastina na aorta foi 34 ± 13 no grupo bicúspide e 36 ± 19 no grupo tricúspide (p=0,31). Na artéria pulmonar, a DOI para elastina foi 30 ± 12 no grupo bicúspide e 29 ± 14 no grupo tricúspide (p=0,34). CONCLUSÕES: Os portadores de VAB apresentaram menor quantidade de fibrilina-1, mas não elastina, na aorta ascendente e artéria pulmonar que os portadores de VAT normal ou doente. Estes achados podem explicar a maior incidência de dilatação e dissecção da aorta ascendente em portadores desta má-formação da valva aórtica.

PURPOSE: Bicuspid aortic valve (BAV) is associated with increased prevalence of annulo-aortic ectasia, dissection and ascending aortic aneurysm. This study was undertaken to compare the amount of fibrillin-1 and elastin in the media of great vessels of patients with bicuspid and tricuspid aortic valve disease. METHOD: Tissue samples of ascending aorta and pulmonary artery were obtained from 22 patients with bicuspid aortic valve disease (BAV) and 17 patients with tricuspid aortic valve disease (TAV), including 6 normal valves from the transplant program. Indirect immunofluorescence and computerized image analyses were used to quantify fibrillin-1 and elastin of the media of the arteries. The results were expressed as the mean integrated optical density (IOD). RESULTS: In the ascending aorta, the IOD for fibrillin-1 was 15 ± 8 in the BAV group and 24 ± 7 in the TAV group (p = 0.001). In the pulmonary artery, the IOD for fibrillin-1 was 18 ± 10 in the BAV group and 25 ± 9 in the TAV group (p = 0.07). In respect to the elastin measurements of the aorta, the specific IOD was 34 ± 13 in the BAV group and 29 ± 14 in the TAV group. In the pulmonary artery the IOD for elastin was 30 ± 12 in the BAV group and 29 ± 14 in the TAV group (p = 0.34). CONCLUSIONS: Patients with BAV were found to have less fibrillin-1 in the ascending aorta and pulmonary artery than patients with TAV. These findings may explain aortic root dilation and ascending aortic dissection in patients with BAV disease.

Theoretical calculations, computer simulations and experiments indicate the possible existence of a ferromagnetic liquid state. Should such a state exist, demagnetization effects would force a nontrivial magnetization texture governed by the shape of the liquid droplet. Since liquid droplets are deformable, the droplet shape couples to the magnetization texture. This paper solves the joint shape/texture problem subject to the assumption of cylindrical droplet symmetry. The shape undergoes a change in topology from spherical to toroidal as exchange energy grows or surface tension decreases.

Para predizer a taxa das reações enzimaticas uma correlação empírica baseada nos resultados experimentais foi desenvolvida. Os modelos representam a ativação e a desativativação da hydrolise enzimatica. Os resultados foram avaliados pela análise de variança (ANOVA). A atividade máxima da tannase foi obtida após 5 minutos de incubação, temperatura 40ºC, pH 4,0, concentração inicial da enzima de 0,12 v/v, concentração inicial do substrato 0,42 mg/ml, força iônica 0,2 M. Sob essas condições a taxa máxima de produção ácido galico foi de 33,49 µmoles/ml/min.

For predicting the rate of enzymatic reaction empirical correlation based on the experimental results obtained under various operating conditions have been developed. Models represent both the activation as well as deactivation conditions of enzymatic hydrolysis and the results have been analyzed by analysis of variance (ANOVA). The tannase activity was found maximum at incubation time 5 min, reaction temperature 40ºC, pH 4.0, initial enzyme concentration 0.12 v/v, initial substrate concentration 0.42 mg/ml, ionic strength 0.2 M and under these optimal conditions, the maximum rate of gallic acid production was 33.49 mumoles/ml/min.