The effect of insulin on the function of the lysosomal apparatus of the neutrophilic leukocytes during the formation of a stress syndrome

In experiments on male rabbits with the lack of insulin it is been revealed violations after the past immobilization the intensivity and duration of neutrophilic leukocytosis decrease, contents of lysosomes in neutrophils, activity of acid phosphatase. By lysosomal ferments don't determine the can observer discordance of processes of coagulation, fibrinolysis, kininogenesis.     

Statistical properties of tropical rainfall intensity measured in Nigeria,for microwave and millimetre wave applications

The statistical properties of measured rainfall intensity, using a rapid response raingauge at Ile-Ife, a Southern Station in Nigeria, are presented in a form suitable for the study of tropical rain attenuation at microwave and millimetre wave bands. The seasonal variation of rainfall intensity is considered in terms of four climatological seasons of the year and the annual cumulative distribution of rainfall rate is compared with theccir curve for zone 1. The frequency of events of various peak rain rates and the duration of rain rates have been analysed. The results of the annual and worst-month analysis of the data are compared with those obtained in other parts of the world.     

The effect of laser surface texturing on transitions in lubrication regimes during unidirectional sliding contact

Laser surface texturing (LST) is an emerging effective method for improving the tribological performance of friction units lubricated with oil. In LST technology, a pulsating laser beam is used to create thousands of arranged microdimples on a surface by a material ablation process. These dimples generate hydrodynamic pressure between oil-lubricated parallel sliding surfaces. The impact of LST on lubricating-regime transitions was investigated in this study. Tribological experiments were conducted with a pin-on-disk apparatus at sliding speeds in the range of 0.015–0.75 m/s and nominal contact pressures that ranged from 0.16 to 1.6 MPa. Two oils with different viscosities (54.8 and 124.7 cSt at 40 °C) were used as lubricants. The test results showed that laser texturing expanded the contact parameters in terms of load and speed for hydrodynamic lubrication, as indicated by friction transitions on the Stribeck curve. The beneficial effects of laser surface texturing are more pronounced at higher speeds and loads and with higher viscosity oil.     

Assessment of utilization of wind energy resources in Nigeria

The study critically reviews the prospects and challenges of utilizing wind energy resources for power generation in Nigeria. The various initiatives by governments and researchers were surveyed and the nation is found to sit in the midst of enormous potential for wind harvest for power generation. The far northern states, the mountainous regions and different places of the central and south-eastern states were identified as good areas for wind harvest together with the offshore areas spanning from Lagos through Ondo, Ogun, Cross-Rivers to Rivers states along the Atlantic Ocean in the south–south. Despite this great potential and huge prospect, the country is found to still suffer from serious energy crises due to her over dependence on hydropower which also is susceptible to seasonal variation in the amount of water levels at dams. There is yet to be committed wind energy project for power generation on-going in the country. Several challenges bedeviling the development and utilization of wind energy resources were identified and suggestions highlighted to help pull the nation out of this lingering energy crisis.     

Polyclonal antibodies from blood and cerebrospinal fluid of patients with multiple sclerosis effectively hydrolyze DNA and RNA

It is known that in the blood of patients with some autoimmune diseases catalytically active antibodies hydrolyzing proteins, DNA, and RNA may be detected. In the present work homogeneous preparations of IgG antibodies (Ab) possessing high affinity for nucleic acids (NA) were obtained for the first time from blood and cerebrospinal fluid of patients with multiple sclerosis (MS). The fraction of IgG Ab as well as its Fab fragments and isolated light chains of both kappa- and lambda-types were shown to catalyze effectively the hydrolysis of DNA and RNA. It is shown by different methods that the capability for nucleic acid hydrolysis is an intrinsic property of the polyclonal Ab. NA-hydrolyzing Ab were detected in the blood of 69 of 72 and in the cerebrospinal fluid of 5 of 5 examined MS patients, while they were not detected in the blood of any of 50 healthy donors examined. Comparison of relative rates of RNA hydrolysis and of the substrate specificity in hydrolysis of various model RNAs--cCMP, poly(U), poly(A), and poly(C)--revealed pronounced differences of MS antibodies from ribonucleases of human blood, ribonuclease A, and all earlier described abzymes. The abzymes are usually characterized by relatively low specific activities in comparison with that of normal enzymes catalyzing analogous reactions. Ab from the blood of MS patients are the first example of autoabzymes whose specific activity in RNA hydrolysis is comparable or even higher than that of pancreatic ribonuclease A--one of the most active RNA-hydrolyzing enzymes.     

Effect of low-zinc status and essential fatty acids deficiency on the activities of aspartate aminotransferase and alanine aminotransferase in liver and serum of albino rats

The effects of dietary deficiencies of zinc and essential fatty acids (EFAs) or both on aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were investigated in young growing rats. Four groups of albino rats were fed diets deficient in either EFA (4% hydrogenated coconut oil) or zinc (6 ppm) or both. The control diet was adequate in EFA (4% soybean oil) and zinc (100 ppm). The feeding trial lasted eight weeks and the activities of AST and ALT were determined in the liver and serum. EFA deficiency had no significant (p > 0.05) effect on liver AST. However, zinc and the double deficiencies depressed AST activity in the organ. Deficiencies of EFA, zinc and their combination depressed ALT activity in the liver significantly (p < 0.05) with a concomitant increase recorded in the serum. The data suggested alteration in endothelial permeability of the plasma membrane and thus leakage of membrane constituents in the tissue studied. It is therefore considered that these deficient diets may affect liver tissue negatively in view of the role of these enzymes in amino acid metabolism.     

User-oriented Security Supporting Inter-disciplinary Life Science Research across the Grid

Understanding potential genetic factors in disease or development of personalised e-Health solutions require scientists to access a multitude of data and compute resources across the Internet from functional genomics resources through to epidemiological studies. The Grid paradigm provides a compelling model whereby seamless access to these resources can be achieved. However, the acceptance of Grid technologies in this domain by researchers and resource owners must satisfy particular constraints from this community - two of the most critical of these constraints being advanced security and usability. In this paper we show how the Internet2 Shibboleth technology combined with advanced authorisation infrastructures can help address these constraints. We demonstrate the viability of this approach through a selection of case studies across the complete life science spectrum.     

Mechanism of transfer film formation during repeat pass sliding of ceramic materials

The formation of transfer film and the consequent effects on the friction and wear behavior of ceramic materials during repeat sliding contact were studied. This was done using four structural ceramics, namely silicon nitride, silicon carbide, alumina and zirconia, with a cylinder-on-flat test configuration.

The transfer film consists of reattached fine wear debris particles, the film, whenever formed, is strongly attached, enough to resist being wiped off by the slider. Calculations suggest that the fine particles are attached primarily by van der Waals forces and to a lesser extent by electrostatic attractive forces. As a consequence, the formation of transfer film leads to a decrease in the wear rate because of the ‘protecting’ role of the film. The presence of the film at the contact interface also results in high friction. The presence of a liquid environment and/or surface active species reduces the particle adhesive forces and hence can inhibit the formation of a transfer film.