A mathematical note on the fahraeuslindqvist effect in power law fluid

An axisymmetric flow of a power law fluid through circular tubes under constant pressure gradient with the flow parameters varying radially is analyzed theoretically. The main finding is that for the Fahraeus-Lindqvist (F-L) effect to occur, it is necessary to have at least one of the parametersK (consistency) andn (index) as a discontinuous function ofr in the absence of wall slip; and with slip condition the parameters could be continuous functions ofr under specific conditions. In both the cases the existence of more than one discontinuity cannot be ruled out. The results obtained are consistent with experimental findings of blood flow through narrow tubes.     

Diurnal variations of serum testosterone levels in the male bonnet monkey (Macaca radiata)

Diurnal variations in serum testosterone levels were studied in six adult maleMacaca radiata. Though the testosterone levels fluctuated considerably during the 24-hr period, a distinctive diurnal pattern characterized by lower concentrations during day hours and higher concentrations during night hours was observed.     

Fresh water chytrids from varanasi (India). IV. Some polycentric forms

In this paper five polycentric chytrids have been described, Nowakowskiella elegans, N. profusa, Polychytrium sp., Catenaria anguillulae and Hyphochytrium catenoides. Of the five species described, N. profusa and Polychytrium sp. are new records from India.     

A physiological study of Saksenaea vasiformis Saksena

Summary The physiological conditions governing growth and sporulation ofSaksenaea vasiformis Saksena, a fungus with outstanding morphological features quite peculiar for Mucorales, were determined. Earlier studies made byTiwari (1955) on a strain of the same species had shown that this fungus is incapable of sporulating on any synthetic medium normally employed for growing fungi.The fungus had been found to have a high tolerance for very low and high pH values. It showed maximum growth at two pH values, one near neutral point, at pH 6, and another at high alkaline pH value, i.e., pH 11. Reason for this behaviour of this fungus has already been discussed. The most suitable temperature for the growth of the fungus was found to be between 30–35° C.Nearly all the carbon, nitrogen and sulphur sources which generally favour growth of fungi were found to support vegetative growth of this fungus as well. However, sporulation in this fungus had peculiar nutritional needs. Only some of the carbon sources, viz., arabinose, rhamnose, sorbose, galactose, lactose and citric acid which supported poor growth, were found to support good or excellent sporulation. But it may be stated that not all carbon sources supporting poor growth could induce sporulation of the organism. Also none of the nitrogen or sulphur sources could induce the fungus to sporulate in presence of glucose as carbon source.     

Growth and enzyme production by Polyporus hirsutus in presence of ammonium sulphate

Summary Growth of Polyporus hirsutus on rice straw rapidly increases its susceptibility to cellulase and xylanase. Addition of ammonium sulphate to the straw (0.1 g/g) enhances cellulase and xylanase production but does not affect laccase production by the fungus although it appears to inhibit its growth.     

Computational predictions of common transcription factor binding sites on the genes of proline metabolism in plants

Proline, an imino acid, has been well documented to be associated with the stress response induced by abiotic factors such as drought, cold and salinity in plants and biotic factors such as bacterial and fungal attacks. However, the regulatory mechanisms controlling proline metabolism, intercellular and intracellular transport and connections of proline to other metabolic pathways are poorly understood. F-MATCH analysis combined with composite module analysis (CMA) revealed that the binding sites matching matrices for O2 and OCSBF-1 were overrepresented in the promoters of differentially expressed proline metabolism genes. The presence of MYBAS1 consensus binding sites occurring in combination with O2 and OCSBF1 in the promoters of genes of proline biosynthesis pathway and SBF1 and GT1 consensus binding sites occurring in combination with O2 and OCSBF1 in the promoters of proline catabolic pathway genes suggest their involvement in modulation of proline metabolism and its accumulation in plants.     

Microwave initiated synthesis and application of polyacrylic acid grafted carboxymethyl cellulose

An environmentally benign and efficient route of synthesis of polyacrylic acid grafted carboxymethyl cellulose (CMC-g-PAA) is developed using microwave radiation alone to initiate the grafting reaction. The synthesis is optimized in terms of percentage grafting and intrinsic viscosity, by varying the microwave irradiation time and monomer (acrylic acid) concentration. The grafted product has been characterized by various physicochemical characterization techniques (intrinsic viscosity measurement, FTIR spectroscopy, SEM morphology study and elemental analysis). FTIR spectroscopy confirmed that free radicals are formed on polysaccharide backbone by cleavage of 1°-OH bond, indicating microwave effect and not thermal decomposition as the cause of free radical generation. The application of the grafted product as flocculant for river water clarification, towards augmentation of drinking water supply has been investigated.     

Common protozoans as an uncommon cause of respiratory ailments in HIV-associated immunodeficiency

Opportunistic infections (OIs) are the leading cause of mortality and morbidity among HIV-positive subjects. The breadth of reports of the rare occurrence of OIs in HIV/AIDS has been increasing over the years and more recent studies have outlined the changing trends in the emergence of newer pathogens. Recent reports of the association of certain protozoans that normally do not infect sites other than their normal sites of localization have generated huge interest among scientists. The complete depression of the immune system, followed by the onset of OIs, especially due to protozoans, i.e. toxoplasmosis, isosporiasis, leishmaniasis, cyclosporosis, microsporidiosis and cryptosporidiosis, is not uncommon in AIDS. The immunologic and pathologic basis behind the susceptibility of immunodepressed individuals to these 'non-site-specific parasites' is likely to have a huge impact on HIV disease progression. Certain possible shortcomings in the immunologic armory of immunodeficient subjects, their failure to contain the establishment of these 'uncommon' agents in the human host and their significance in HIV disease progression are discussed.     

MTHFR Gene Polymorphism and Its Relationship with Plasma Homocysteine and Folate in a North Indian Population

There is a paucity of data on the prevalence of elevated homocysteine and its relation with plasma folate and the methylenetetrahydrofolate reductase (MTHFR) gene in the population of North India. This study evaluates MTHFR gene polymorphism and its relationship with plasma homocysteine and folate levels in a healthy North Indian population. The age of the 200 subjects included in this study was in the range 18–73 (mean 39.4) years. The plasma homocysteine level was elevated in 56.5%, and the plasma folate level was low in 49.5% of the subjects. Heterozygous MTHFR gene polymorphism (CT) was present in 15.5%, and homozygous (TT) in 3.5% of the subjects. Age, diet, and MTHFR gene polymorphisms were related to homocysteine level. All the subjects with the TT and 79% with the CT genotype had a high level of plasma homocysteine, whereas 51% with the CC genotype had a high homocysteine level. After adjustment for the effect of covariates, however, homocysteine was not related to MTHFR gene polymorphism.