Conditional rifampicin sensitivity of a rif mutant of Escherichia coli: rifampicin induced changes in transcription specificity

Arif mutantof Escherichia coli that exhibits medium and temperature-dependent sensitivity to rifampicin is described. In the absence of rifampicin, this strain grows in minimal and rich media at 30° C and 42°C. In its presence it is viable in rich medium at both temperatures, but in minimal medium only at 30°C. In minimal-rifampicin medium at the higher temperature, RNA synthesis is decreased. The addition of certain divalent salts (MgSO4, CaCl2, BaCl2) in excess, or chelators (EDTA, EGTA, o-phenanthrolein) greatly increase viability in minimal-rifampicin medium at 42°C. Excess MgSO4 (10 mM) also increases the rate of RNA synthesis in the same medium. A model is proposed wherein therif mutation is suggested to cause a structural change in RNA polymerase that allows the binding of rifampicin and other ligands at 42° C. Rifampicin-binding is suggested to alter the conformation of RNA polymerase, impairing its ability to express genes required for growth in minimal medium. Implicit in this view is the assumption that these genes are structurally different from those expressed in rich medium in respect of certain template features recognized by RNA polymerase

Identification of Beryllium Hydride Isotopomer Lines in Sunspot Umbral Spectra

A high resolution spectrum of FTS sunspot umbra of NSO/Kitt Peak was used to conduct a search for the molecular absorption lines due to BeH, BeD and BeT isotopomers. Analysis led to estimates of identification of the molecular lines of bands A - X (0,0), (1,1) and (2,2) for BeH, A - X (0,0), (1,1), (2,2) and (3,3) for BeD and of A - X (0,0), (1,1) and (2,2) for BeT. Among the identified lines, those which are well resolved were selected for measurements to calculate equivalent widths. The values of effective rotational temperature T were estimated for bands A - X(1,1) and (2,2) of BeH, A - X(1,1) of BeD and A - X(2,2) of BeT to be 4228K, 4057K, 3941K and 3243K respectively

A Loosely Coupled Approach for the CFD Code US3D and Radiation Code NEQAIR

Couple the CFD code, US3D, with the radiation code, NEQAIR. Implement line of sight extraction tool for an unstructured grid

The white matter connectome as an individualized biomarker of language impairment in temporal lobe epilepsy.

ObjectiveThe distributed white matter network underlying language leads to difficulties in extracting clinically meaningful summaries of neural alterations leading to language impairment. Here we determine the predictive ability of the structural connectome (SC), compared with global measures of white matter tract microstructure and clinical data, to discriminate language impaired patients with temporal lobe epilepsy (TLE) from TLE patients without language impairment.MethodsT1- and diffusion-MRI, clinical variables (CVs), and neuropsychological measures of naming and verbal fluency were available for 82 TLE patients. Prediction of language impairment was performed using a robust tree-based classifier (XGBoost) for three models: (1) a CV-model which included demographic and epilepsy-related clinical features, (2) an atlas-based tract-model, including four frontotemporal white matter association tracts implicated in language (i.e., the bilateral arcuate fasciculus, inferior frontal occipital fasciculus, inferior longitudinal fasciculus, and uncinate fasciculus), and (3) a SC-model based on diffusion MRI. For the association tracts, mean fractional anisotropy was calculated as a measure of white matter microstructure for each tract using a diffusion tensor atlas (i.e., AtlasTrack). The SC-model used measurement of cortical-cortical connections arising from a temporal lobe subnetwork derived using probabilistic tractography. Dimensionality reduction of the SC was performed with principal components analysis (PCA). Each model was trained on 49 patients from one epilepsy center and tested on 33 patients from a different center (i.e., an independent dataset). Randomization was performed to test the stability of the results.ResultsThe SC-model yielded a greater area under the curve (AUC; .73) and accuracy (79%) compared to both the tract-model (AUC: .54, p < .001; accuracy: 70%, p < .001) and the CV-model (AUC: .59, p < .001; accuracy: 64%, p < .001). Within the SC-model, lateral temporal connections had the highest importance to model performance, including connections similar to language association tracts such as links between the superior temporal gyrus to pars opercularis. However, in addition to these connections many additional connections that were widely distributed, bilateral and interhemispheric in nature were identified as contributing to SC-model performance.ConclusionThe SC revealed a white matter network contributing to language impairment that was widely distributed, bilateral, and lateral temporal in nature. The distributed network underlying language may be why the SC-model has an advantage in identifying sub-components of the complex fiber networks most relevant for aspects of language performance

Influence of regular exercise on cardiac autonomic activity in. healthy young women during the normal menstrual cycle

ABSTRACT Regular physical exercise leads to considerable changes demonstrated in the increase of health related fitness. Heart rate variability is a measure of autonomic nervous system function. Gonadotropin hormones affect autonomic nervous system function. Regular exercise is thought to modulate the sympathovagal control of the heart leading to an enhancement of the vegetative control of the heart. The present study aims to describe the heart rate variability and assesses its association with regular exercise and menstrual cycle in healthy young women in frequency domain method in different phases of menstrual cycle. A total of 54 female students were selected. The selected students were divided into two groups namely Group I consisted of subjects doing regular physical exercise for 30 minute each day and Group II consisted of individuals who were non exercisers the ECG recording were taken during the 3 phases of menstrual cycle. The analog ECG signal were conveyed through an A/D converter to PC and were analyzed .The frequency domain analysis was done in which the LF, HF and LF/HF components were studied. Results showed that a significant increase in the LF/HF ratio in the luteal phase of menstrual cycle in the non exercisers group when compared to other phases of the menstrual cycle (P<0.001) . Regular exercisers had more parasympathetic activity than non exercisers. Detection of sympatho vagal inbalance at an early age based on regular exercising with necessary life style modification could decrease the incidence of cardiovascular diseases as age advances

The key project managers’ competences for different types of projects

This paper describes a quantitative research approach for identifying key project managers’ competences for different types of projects. By identifying the perceived most valuable project manager competences, as having the most potential for increased contribution to project management (PM) performance, practitioners and organizations can select their priorities when developing their PM practices. The 46 competences (technical, behavioural and contextual) provided by IPMA (International Project Management Association) were surveyed through an online questionnaire. Three dimensions to distinguish project types were used: application area, innovation and complexity. Completed questionnaires were received from 96 project managers from Portugal. The results showed that 13 key competences (20%) were common to the majority of the projects. Most of these are behavioural competences, such as: ethics, reliability, engagement, openness, and leadership. It was also observed a clear correlation between technical competences and project complexity

Small cell carcinoma of the anus: a case report

Small cell carcinoma of the anus is a very rare but aggressive tumour. We present a case of a 60-year old lady with small cell carcinoma of the anus. She had no metastatic disease on presentation. She had chemotherapy and radiotherapy but developed distant metastasis after completion of treatment. Immunohistochemistry is required to make a diagnosis. Chemotherapy remains the mainstay of treatment for small cell carcinoma of the anus with or without metastatic disease. Radiotherapy is for local control and relief of symptoms

Repositioning: the fast track to new anti-malarial medicines?

Repositioning of existing drugs has been suggested as a fast track for developing new anti-malarial agents. The compound libraries of GlaxoSmithKline (GSK), Pfizer and AstraZeneca (AZ) comprising drugs that have undergone clinical studies in other therapeutic areas, but not achieved approval, and a set of US Food and Drug Administration (FDA)-approved drugs and other bio-actives were tested against Plasmodium falciparum blood stages. Repositioning of existing therapeutics in malaria is an attractive proposal. Compounds active in vitro at muM concentrations were identified. However, therapeutic concentrations may not be effectively achieved in mice or humans because of poor bio-availability and/or safety concerns. Stringent safety requirements for anti-malarial drugs, given their widespread use in children, make this a challenging area in which to reposition therapy.This work was supported by the Medicines Malaria Venture, St Jude Children's Research Hospital, GlaxoSmithKline Plc and Pfizer Inc