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Dengue fever is an acute febrile viral illness characterized by severe headache, myalgia, arthralgia, rashes, leucopenia and thrombocytopenia. Patients may face haemorrhagic complications like gastrointestinal bleeding, intracranial haemorrhage, menorrhagia, hematomas, hematuria and massive epistaxis. Ischemic stroke in dengue fever is a rare scenario; and Parkinsonism following basal ganglia infarction in dengue fever, to the best of our knowledge, has not been reported yet.

Soil-cement blocks are employed for load bearing masonry buildings. This paper deals with the study on the influence of bed joint thickness and elastic properties of the soil-cement blocks, and the mortar on the strength and behavior of soil-cement block masonry prisms. Influence of joint thickness on compressive strength has been examined through an experimental program. The nature of stresses developed and their distribution, in the block and the mortar of the soil-cement block masonry prism under compression, has been analyzed by an elastic analysis using FEM. Influence of various parameters like joint thickness, ratio of block to mortar modulus, and Poisson's ratio of the block and the mortar are considered in FEM analysis. Some of the major conclusions of the study are: (1) masonry compressive strength is sensitive to the ratio of modulus of block to that of the mortar ([E.sub.b]/[E.sub.m]) and masonry compressive strength decreases as the mortar joint thickness is increased for the case where the ratio of block to mortar modulus is more than 1; (2) the lateral tensile stresses developed in the masonry unit are sensitive to the [E.sub.b]/[E.sub.m] ratio and the Poisson's ratio of mortar and the masonry unit; and (3) lateral stresses developed in the masonry unit are more sensitive to the Poisson's ratio of the mortar than the Poisson's ratio of the masonry unit. DOI: 10.1061/(ASCE)0899-1561(2009)21:10(535) CE Database subject headings: Soil cement; Masonry; Mortars; Stress strain relations; Lateral stress; Poisson ratio.

The strength of rock mass probably is the first engineering parameter that a geotechnical engineer may be keen to establish before the start of any mining and civil engineering project. The strength of a rock mass at site is generally influenced by joint geometry and the stress state that it experiences. Field studies show that stress conditions around underground structures will be generally true triaxial or polyaxial, i.e., [[sigma].sub.1] > [[sigma].sub.2] > or [[sigma].sub.3]. The rock mass behavior in such field conditions can effectively be simulated in laboratory by conducting large-scale physical modeling. In this study the most commonly occurring joint configurations (three joint sets) were created on rock mass models in the laboratory and tested under polyaxial stress compression. The model rock was a sand-lime block with low strength and medium deformability. The joint configurations were varied to assess the influence of joint geometry on the stress-strain curve, failure mechanism, and strength anisotropy. Similarly, on each type of geometry, [[sigma].sub.2] / [[sigma].sub.3] ratio was also varied to study the effect of intermediate principal stress on engineering behavior of rock mass. The maximum enhancement of 310% in strength due to an increase in the [[sigma].sub.2] / [[sigma].sub.3] ratio was observed, which corresponded to joint inclination, [theta] = 60 [degrees]. Based on testing results, the polyaxial strength criterion was evolved similar to the von-Mises failure envelope. DOI: 10.1061/(ASCE)0899-1561 (2007)19:5(393) CE Database subject headings: Rock masses; Model studies; Anisotropy; Triaxial compression; Failures; Joints.

Large numbers of soil-cement block masonry buildings exist in India and many other countries. The paper deals with an experimental study on the influence of soil grading on the characteristics of soil-cement blocks and shear-bond strength of soil-cement block masonry triplets. Influence of clay content of the soil-cement block on strength, absorption and durability characteristics, and interfacial mortar-block bond strength has been examined. Some of the major conclusions of the study are: (1) optimum clay content leading to maximum strength is in the range of 14-16%; (2) saturated water content of the blocks increases with increase in clay content of the block; (3) initial rate of absorption decreases with increase in clay content of the block; (4) weight loss after ASTM wire scratch test is minimum when the clay content of the block is about 16%; and (5) optimum clay content for the highest modulus for the blocks and for highest shear-bond strength is about 16%. DOI: 10.1061/(ASCE)0899-1561(2007)19:2(139) CE Database subject headings: Soil-cement; Compressive strength; Durability; Soil stabilization; Bonding strength; Stress strain relations.

Soil-cement blocks are used for the load bearing masonry of 2-3-story buildings. Flexural and shear strength of such walls greatly depend upon the bond strength between the block and the mortar. This paper deals with the methods of improving the shear-bond strength of soil-cement block masonry (without altering the mortar characteristics) and the influence of shear-bond strength on masonry compressive strength. Altering the texture of bed faces of the block, size and area of the frog, and certain surface coatings have been attempted to enhance the shear-bond strength. The results indicate that: (1) rough textured bed face of the blocks yields higher shear-bond strength than the plain surface; (2) use of fresh cement-slurry coating on the bed faces improves the shear-bond strength considerably; (3) no significant changes are noticed in the compressive strength and stress-strain characteristics of soil-cement block masonry due to changes in shear-bond strength: and (4) masonry has a higher straining capacity than that of the block and the mortar. DOI: 10.1061/(ASCE)0899-1561(2007)19:2(164) CE Database subject headings: Soil cements; Masonry; Bonding strength: Blocks; Stress strain relations: Mortars.

Seismic passive earth pressure coefficients were computed by the method of limit equilibrium using a pseudostatic approach for seismic forces. Composite curved rupture surfaces were considered in the analysis. While earlier studies using this type of analysis were mainly for sands, seismic passive earth pressure coefficients were obtained in the present study considering the effects of cohesion, surcharge, and own weight. The minimum seismic passive force was obtained by adding the individual minimum values of these components and the validity of the principle of superposition was examined. Other parameters considered in the analysis were wall batter angle, ground surface slope, soil friction angle, wall friction angle, wall adhesion to soil cohesion ratio, and horizontal and vertical seismic accelerations. The seismic earth pressure coefficients were found to be highly sensitive to the seismic acceleration coefficients both in the horizontal and vertical directions. Results of the study are presented in the form of figures and tables. Comparisons of the proposed method with available theories in the seismic case are also presented. CE Database subject headings: Retaining walls; Seismic analysis; Passive pressure; Soil pressure; Limit equilibrium.

A study was conducted to examine the mechanistic features and synthetic possibilities associated with the reductive activation of selenosilane to its radical anion using a novel photosystem. The transient absorption spectra were determined by pulse radiolysis and associated with the time-resolved absorption spectral data. Results indicated that the photosystem can effectively determine the reductive activation of -Si-Se- bonds.

This paper presents an approximate three-dimensional elasticity solution for an infinitely long, cross-ply laminated circular cylindrical shell panel with simply supported boundary conditions, subjected to an arbitrary discontinuous transverse loading. The solution is based on the principal assumption that the ratio of the thickness of the lamina to its middle surface radius is negligible compared to unity. The validity of this assumption and the range of application of this approximate solution have been established through a comparison with an exact solution. Results of classical and first-order shear deformation shell theories have been compared with the results of the present solution to bring out the accuracy of these theories. It is also shown that for very shallow shell panels the definition of a thin shell should be based on the ratio of thickness to chord width rather than the ratio of thickness to mean radius.

The mechanistic aspects and synthetic potentials of photosensitized electron transfer (PET) reductive activation of organoselenium substrates were studied. PET activation of substrates were accomplished through a photosystem composed of light-absorbing 1,5-dimethoxynaphthalene (DMN) as electron donor and ascorbic acid as co-oxidant. The fluorescence quenching of DMN by organoselenium compounds, correlation of fluorescence quenching rate constant with the reduction potentials of the compounds, and the dependence of photodissociation quantum yields indicated the occurrence of electron transfer processes.