The evolution of primate malaria parasites based on the gene encoding cytochrome b from the linear mitochondrial genome

We report a phylogenetic analysis of primate malaria parasites based on the gene encoding the cytochrome b protein from the mitochondrial genome. We have studied 17 species of Plasmodium, including 14 parasitic in primates. In our analysis, four species were used for rooting the Plasmodium phylogenetic tree: two from closely related genera (Hepatocystis sp. and Haemoproteus columbae) and two other Apicomplexa (Toxoplasma gondii and Theileria parva). We found that primate malaria parasites form a monophyletic group, with the only exception being the Plasmodium falciparum-Plasmodium reichenowi lineage. Phylogenetic analyses that include two species of non-Plasmodium Haemosporina suggest that the genus Plasmodium is polyphyletic. We conclude that the biologic traits, such as periodicity and the capacity to relapse, have limited value for assessing the phylogenetic relationships among Plasmodium species. For instance, we found no evidence that would link virulence with the age of the host-parasite association. Our studies also reveal that the primate malaria parasites originated in Africa, which contradicts the presently held opinion of Southeast Asia as their center of origin. We propose that the radiation of Asian monkey parasites is a recent event where several life history traits, like differences in periodicity, appeared de novo.     

Pervasive power: a radioisotope-powered piezoelectric generator

A long-lasting radioisotope micropower generator for self-powered sensor microsystems promises to make pervasive computing systems more reliable. Its higher energy conversion efficiency enables microsystems with small amounts of radioactivity to realize sensor and basic computation operations. The goal is to achieve power sources that operate over a wide temperature range and for extended time periods with high reliability. To reach this goal, researchers have investigated technologies for miniature micropower applications and developed radioisotope power generators. We've created a power source employing radioactive thin films and piezoelectric unimorphs, using a nonthermal energy conversion cycle that enables much higher energy conversion efficiency.     

Taxon-specific differences in responsiveness to capsaicin and several analogues: Correlates between chemical structure and behavioral aversiveness

The present set of experiments was designed to explore avian insensitivity to capsaicin. Based upon a molecular model of avian chemosensory repellency, we hypothesized that structural modifications of the basic capsaicin molecule, which is itself not aversive to birds, might produce aversive analogues. To this end, European starlings (Sturnus vulgaris) and Norway rats (Rattus norvegicus) were given varied concentrations of synthetic capsaicin and four analogues (methyl capsaicin, veratryl amine, veratryl acetamide, vanillyl acetamide) in feeding and drinking tests. The results agreed with a model that we are developing to describe the chemical nature of avian repellents. Synthetic capsaicin and vanillyl acetamide were not repellent to birds, owing to the presence of an acidic phenolic OH group. Conversely, veratryl acetamide was aversive, due to the basic nature of this compound. For rats, repellent effectiveness among compounds was reversed: synthetic capsaicin was the best repellent while veratryl acetamide was the worst. We speculate that this taxonomic reversal may reflect basic differences in trigeminal chemoreception. In any case, it is clear that chemical correlates of mammalian repellents are opposite to those that predict avian repellency.     

MRI of the brain in patients with miliary pulmonary tuberculosis without symptoms or signs of central nervous system involvement

MRI was performed on patients with miliary pulmonary tuberculosis to look for brain involvement and to study the features sequentially, during treatment. We studied seven patients with typical radiographic tuberculosis, and no symptoms or signs of central nervous system involvement. Conventional spin-echo (SE) imaging, including contrast enhanced images, was performed in all cases. All patients showed brain involvement: four patients showed lesions mainly less than 3 mm in diameter, better seen on contrast-enhanced images. These patients showed oedema around the lesions after 2 months of treatment, with subsequent regression on follow-up. The remaining three patients had multiple lesions, 3 mm or more in diameter, which showed a gradual decrease on follow-up. We conclude that the brain may commonly be involved in miliary pulmonary tuberculosis. The response to treatment depends on the stage of the granuloma and shows a definite pattern of healing on follow-up.     

Giving children security: Mamie Phipps Clark and the racialization of child psychology.

During the 1930s and 1940s, social psychologists became increasingly well-known among progressives battling race prejudice. By the early 1950s, African American psychologist Kenneth Bancroft Clark had become deeply involved with the National Association for the Advancement of Colored People's battle against segregated education in the South. By this time, his wife, who is less well-known in the annals of history, was developing her own reputation as the guiding spirit behind Harlem's Northside Center for Child Development. Her work at the center helped define an increasing interest in the psychology of children of color. This article examines the individual and social contexts of Mamie Phipps Clark's life and argues for greater attention to the dynamics of race and gender in the history of psychology. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A testbed for performance evaluation of load‐balancing strategies for Web server systems

To improve response time of a Web site, one replicates the site on multiple servers. The effectiveness of a replicated server system will depend on how the incoming requests are distributed among replicas. A large number of load‐balancing strategies for Web server systems have been proposed. In this paper we describe a testbed that can be used to evaluate the performance of different load‐balancing strategies. The testbed uses a general architecture which allows different load‐balancing approaches to be supported easily. It emulates a typical World Wide Web scenario and allows variable load generation and performance measurement. We have performed some preliminary experiments to measure the performance of a few policies for load balancing using this testbed. Copyright © 2003 John Wiley & Sons, Ltd.     

Water quality management of a stretch of river Yamuna: An interactive fuzzy multi-objective approach

This paper presents an Interactive Fuzzy Multi-Objective Linear Programming (IFMOLP) model for water quality management in a river basin. The IFMOLP model formulated will first evaluate dissolved oxygen (DO) concentrations or DO deficits at a point in different reaches depending on the overall Biochemical Oxygen Demand (BOD) concentration present in the respective drain. Subsequently, the model incorporates the aspirations and conflicting objectives of the decision maker (DM) by taking into consideration the aspects relevant for pollution control boards as well as dischargers responsible for generating wastewater. The uncertainty associated with specifying the water quality criteria (based on DO concentration or DO deficit) and treatment cost to remove pollution level is incorporated by interacting the decision maker. In this process DM is asked to specify the reference aspiration levels of achievement for the values of all membership functions generated with respect to each objective. This provides flexibility for the pollution control authorities and dischargers to specify their aspirations. IFMOLP model developed herein is then used in a case study for the evaluation of optimal BOD removal in different drains located across the river Yamuna at New Delhi, India. The presented model will simulate the allocation of waste load efficiencies with satisfactory results which will indicate usefulness of the model in managing more complex river basins along with better flexible policies of water management.     

Thermal,spectral and morphological studies on cellulose,cellulose ethylthiophosphate and its metal complexes in air

Metal complexes of thiophosphorylated cellulose, when heated, give rise to high char yields. These and related observations suggest that such derivatisation may give rise to novel flame retardant treatments for cellulosic materials. The kinetics of thermal degradation of cellulose, cellulose ethylthiophosphate (CESP) and metal complexes of the CESP have been studied by thermogravimetry (TG) and differential thermal analysis (DTA) from ambient temperature to 700°C in dynamic air to investigate the potential flame retardance of the CESP and its metal complexes. Various parameters such as energy, entropy, enthalpy and free energy of activation have been calculated using the Broido method and transition state theory. For the decomposition stage of thermal degradation, the activation energies of the CESP samples lie in the range 53-133 kJmol^?1 and of the metal complexes, 108-177kJmol^?1, which are found to be lower than that of cellulose (187 kJmol^?1). Scanning electron micrographs of the CESP show that the fibrillar structure of cotton has become more evident and chars retain the general morphology of the original fibre although severe, localised zones of damage reflect the gross chemical and physical changes occurring during pyrolysis. The IR spectra of chars of modified samples indicate formation of compounds containing C=O, C=C and P=O groups. The mechanisms of thermal degradation of the CESP and its metal complexes have been proposed.     

Finite element method in magnetohydrodynamic channel flow problems

The finite element method has been applied to the steady-state fully developed magnetohydrodynamic channel flow of a conducting fluid in the presence of transverse magnetic field. Simple elements have been used to obtain the numerical values of velocity and induced magnetic field. To test the efficiency of the method, three different geometries, viz., rectangle, circle and triangle, are taken as the section of the pipe whose walls are non-conducting. Comparison is made with those cases in which exact solutions are available. Apart from giving good results, the FEM makes it possible to solve the problem for a pipe with arbitrary cross-section which was not possible by the other methods.