Biodegradation of rocket propellant waste, ammonium perchlorate

The short term effects of ammonium perchlorate on selected organisms were studied. A long term experiment was also designed to assess the changes incurred by ammonium perchlorate on the nitrogen and chloride contents of soil within a period of 3 years. In addition, an attempt was made to produce methane gas from anaerobic fermentation of the aquatic weed, Alternanthera philoxeroides

Development and testing of an assessment tool for integrated learning

Objective: Development of integrated questions for undergraduate medical students and assessing students’ capability to retain and apply basic concepts in an integrated way. Method: Multiple choice questions, attempting to probe understanding and application of different concepts, affiliated with different subjects and topics, were developed. As a pilot these were administered to the students of third year and final year at the end of their certifying examinations as a mock test. The following year these questions were introduced in the continuous assessments and subsequently the certifying examinations (in third year) as 33% of the whole examination. Difficult indices, item analysis and internal consistency (alpha) were calculated for all the questions. Results: The difficulty indices of integrated questions indicated that students found the integrated questions difficult. Conclusion: There was a significant change of distribution in terms of scoring for the integrated questions. Students’ power to integrate showed reliable improvement when tested in the certifying examinations (JPMA 51:384,2001)

Chloramphenicol therapy of typhoid fever

In a prospective study we compared two different dosage regimens of IV chloramphenicol succinate (100 mg/kg/day and 75 mg/kg/day) in children with culture proven typhoid. Trough and peak blood samples, obtained at 48 hrs, were analysed for free chloramphenicol by high pressure liquid chromatography (HPLC). Although the mean trough (8.8 +/- 7.7 versus 5.4 +/- 2.6 mcg/ml) and peak (19.9 +/- 12.2 versus 15.4 +/- 6.1 mcg/ml) chloramphenicol concentrations were comparable in both groups, a significantly wider range was found in the group receiving 100 mg/kg/day. Potentially toxic levels (greater than 30 mcg/ml) developed in two patients with liver dysfunction. Chloramphenicol in a dosage of 75 mg/kg/day is adequate and safe for the treatment of paediatric typhoid

Evaluation of quality assurance instruments in higher education institutions: A case of Oman

The use of a variety of instruments for quality assurance, management, and enhancement in higher education is well recognized. This article investigated the instruClose Panelments used by Higher Education Institutions (HEIs) in Oman to measure, control, and manage the quality of their services in alignment with the standards set by Oman Academic Accreditation Authority (OAAA). Quality Assurance Managers (QAMs) from five HEIs were interviewed to identify the instruments used by them to fulfil the requirements of each standard and the way they make use of the data gathered by using these instruments. Findings from the study reveal that questionnaires and meetings are the most common instruments used by these institutions to measure, control and assure the efficacy of their current quality activities. In addition, HEIs use summary statistics to analyse data and then present them in meetings or through reports. On the other hand, it was found that substantial efforts are made to collect data but the efficient usage of data is missing. The QAMs reported a lack of awareness among the staff on the importance of collecting data since the staff members believe that these data are collected for documentation purposes only. This study emphasizes the importance of using the data gathered from different instruments in decision making and enhancing the quality of HEIs

Pacing stress echocardiography: an alternative to pharmacologic stress testing

AbstractOBJECTIVESWe sought to evaluate the diagnostic accuracy and feasibility of bedside pacing stress echocardiography (PASE) as a potential substitute for pharmacologic stress echocardiography in patients admitted to the hospital with new-onset chest pain or worsening angina pectoris.BACKGROUNDAccurate and rapid noninvasive identification and evaluation of the extent of coronary artery disease (CAD) is essential for optimal management of these patients.METHODSBedside transthoracic stress echocardiography was performed in 54 consecutive patients admitted to a community hospital with new-onset chest pain, after acute myocardial infarction had been excluded. We used 10F transesophageal pacing catheters and a rapid and modified pacing protocol. The PASE results were validated in all patients by coronary angiography performed within 24 h of the test. Significant CAD was defined as ≥75% stenosis in at least one major epicardial coronary artery.RESULTSThe sensitivity of PASE for identifying patients with significant CAD was 95%, specificity was 87% and accuracy was 92%. The extent of significant CAD (single- or multivessel disease) was highly concordant with coronary angiography (kappa = 0.73, p < 0.001). Pacing stress echocardiography was well tolerated, and only 4% of the patients had minor adverse events. The mean rate–pressure product at peak pacing was 22,313 ± 5,357 beats/min per mm Hg, and heart rate >85% of the age-predicted target was achieved in 94% of patients. The average duration of the bedside PASE test, including image interpretation, was 38 ± 6 min.CONCLUSIONSBedside PASE is rapid, tolerable and accurate for identification of significant CAD in patients admitted to the hospital with new-onset chest pain or worsening angina pectoris

Co-pyrolysis of Rice Husk with Underutilized Biomass Species: A Sustainable Route for Production of Precursors for Fuels and Valuable Chemicals

In this study, co-pyrolysis of rice husk with underutilized biomass, Napier grass and sago waste was carried out in a fixed bed reactor at 600 �C, 30 �C/min and 5 L/min nitrogen flowrate. Two-phase bio-oil (organic and aqueous) was collected and characterized using standard analytical techniques. 34.13–45.55 wt% total boil-oil yield was recorded using assorted biomass compared to pure risk husk biomass with 31.51 wt% yield. The organic phase consist mainly benzene derivatives with higher proportion in the oil from the co-pyrolysis process relative to the organic phase from the pyrolysis of the individual biomass while the aqueous phase in all cases was predominantly water, acids, ketones, aldehydes, sugars and traces of phenolics. This study has demonstrated a good approach towards increasing valorization of rice husk in a single reaction step for the production of high grade bio-oil, which can be transformed into fuel and valuable chemicals

Initial MST radar observations of upper tropospheric-lower stratospheric duct-like structures over Jicamarca, Peru

Persistent wind jet structures along zonal and meridional fields, believed to be caused by stationary gravity waves, were detected in February 1999 in mesosphere-stratosphere-troposphere (MST) radar wind measurements of the troposphere and lower stratosphere over Jicamarca, Peru. Over a continuous seven day span of MST-data analyzed in this study, two days of observations showed signatures of wave-like structures in the upper troposphere/lower stratosphere wind jets associated with the phases of the stationary gravity waves. We believe these wave-like structures are ducted gravity waves. We present these initial observations, their characteristics, and the results of simple numerical simulations used in an attempt to mimic these observed features. Although a fair replication of the observed ducted structure in the numerical model is found, the observed period of ~90 min is nonetheless much longer than what is traditionally observed. As a result, the specific physical nature of the observed structures is not fully established. Nevertheless, given the high quality of the observations, we demonstrate here that continued analysis of this data set and concurrent modeling efforts will allow for a better understanding of Doppler ducts at high spatial and temporal resolution, and the results presented here can ultimately be applied to studies of middle atmospheric fronts, ducts, and bores

Classification of hyperbolic Dynkin diagrams, root lengths and Weyl group orbits

We give a criterion for a Dynkin diagram, equivalently a generalized Cartan matrix, to be symmetrizable. This criterion is easily checked on the Dynkin diagram. We obtain a simple proof that the maximal rank of a Dynkin diagram of compact hyperbolic type is 5, while the maximal rank of a symmetrizable Dynkin diagram of compact hyperbolic type is 4. Building on earlier classification results of Kac, Kobayashi-Morita, Li and Sa\c{c}lio\~{g}lu, we present the 238 hyperbolic Dynkin diagrams in ranks 3-10, 142 of which are symmetrizable. For each symmetrizable hyperbolic generalized Cartan matrix, we give a symmetrization and hence the distinct lengths of real roots in the corresponding root system. For each such hyperbolic root system we determine the disjoint orbits of the action of the Weyl group on real roots. It follows that the maximal number of disjoint Weyl group orbits on real roots in a hyperbolic root system is 4.Comment: J. Phys. A: Math. Theor (to appear

Study of Two-Step Mechanisms in Pion Absorption on 6Li, 12C via Deuteron Emission

The (pi+,pd), and (pi+,dd) reactions were investigated with pions of 100 and 165 MeV kinetic energy on 6Li and 12C targets. In comparison with previously published (pi+,pp) data on the same targets and at the same beam energies, kinematic regions were identified in which the neutron pickup process n+p->d dominated the observed deuteron yield. The importance of this mechanism increases with energy, contributing half of the observed cross section at 165 MeV. The contribution of direct quasi-triton absorption is significant only at 100 MeV.Comment: 23 pages, 12 figure