Dynamics of Viscous Dissipative Plane Symmetric Gravitational Collapse

We present dynamical description of gravitational collapse in view of Misner and Sharp's formalism. Matter under consideration is a complicated fluid consistent with plane symmetry which we assume to undergo dissipation in the form of heat flow, radiation, shear and bulk viscosity. Junction conditions are studied for a general spacetime in the interior and Vaidya spacetime in the exterior regions. Dynamical equations are obtained and coupled with causal transport equations derived in context of M$\ddot{u}$ller Israel Stewart theory. The role of dissipative quantities over collapse is investigated.Comment: 17 pages, accepted for publication in Gen. Relativ. Gra

Biochemical predictors of outcome of pituitary surgery for cushing's disease

Objective: Transsphenoidal surgery (TS) is the primary therapy for Cushing's disease (CD). The aims of this retrospective study were twofold: (i) investigate early and late results of TS forCD, and (ii) evaluate various postoperative tests in order to predict the outcome of TS. Methods: We reviewed the long-term outcome in 79 patients with CD who underwent TS (median follow-up 84 months, range 6-197). Within 2 weeks after surgery, morning serum cortisol concentrations were obtained (n = 78) and corticotropin-releasing hormone (CRH) (n = 53) and metyrapone tests (n = 72) were performed. Three groups of outcome were identified: sustained remission, early failure (persistent CD), and late relapse. Results: Immediate postoperative remission was achieved in 51 patients (65%), whereas 28 patients (35%) had persistent CD after TS. Ten patients developed recurrent CD after initial remission (20%). Morning cortisol: all relapses but one recorded serum cortisol >50 nmol/l. A cortisol threshold value of 200 nmol/l has a positive predictive value of 79% for immediate surgical failure (negative predictive failure [NPV] 97%). CRH test: CRH-stimulated peak cortisol ≥600 nmol/l predicted early failure in 78% (NPV 100%). All relapses recorded CRH-stimulated peak cortisol ≥485 nmol/l. Metyrapone test: 11-deoxycortisol ≥345 nmol/l predicted an early failure in 86% of cases (NPV 94%). Conclusion: Predictive factors of surgical failure are morning cortisol ≥200 nmol/l, 11-deoxycortisol ≥345 nmol/l after metyrapone and CRH-stimulated cortisol ≥600 nmol/l. CRH and/or metyrapone testing are not superior to morning cortisol concentration in the prediction of outcome of TS. Careful long-term follow-up remains necessary independent of the outcome of biochemical testing. Copyrigh

Development of a thermal reclamation system for spent blasting abrasive

Abrasive blasting is the most economical method for paint removal from large surface areas such as the hulls and tanks of oceangoing vessels. Tens of thousands of tons of spent abrasive are generated annually by blasting operations in private and US Navy shipyards. Some of this material is classified as hazardous waste, and nearly all of it is currently being either stockpiled or disposed in landfills. The rapid decline in available landfill space and corresponding rise in landfill tipping fees pose a severe problem for shipyard operators throughout the US. This paper discusses the results of a research and development program initiated by the Institute of Gas Technology and supported by the US Navy to develop and test a fluidized-bed thermal reclamation system for spent abrasive waste minimization. Bench- and pilot-scale reclaimer tests and reclaimed abrasive performance tests are described along with the current status of a program to build and test a 5-ton/hour prototype reclaimer at a US Navy shipyard

Advancements in transition metal-catalyzed 1,2,3-triazole synthesis via azide-alkyne cycloaddition

1,2,3-triazoles have emerged as important structural motifs in chemical biology, attracting increasing focus in recent years because of their wide range of uses. These compounds can be efficiently synthesized using click reactions. Its versatility makes it valuable in drug discovery and materials science. Significant advancements have been made in recent years in the process of making 1,2,3-triazoles, reflecting the growing curiosity and investment in the area of research. The catalytic performance of transition metals Cu, Ir, Rh, Ru, Ni, Pd, Au, Ag, and Zn, which were used as ligands and salts in the azide-alkyne cycloaddition method of 1,2,3-triazole synthesis, has been covered in this review. Cu-complexes and salts were found to be more effective for selective synthesis among all transition metals. Furthermore, it is determined that some azide-alkyne reactions are entirely catalytic in nature and cannot be carried out as such by switching transition metals.</p

Sleep deprivation and its associated factors among general ward patients at a tertiary care hospital in Pakistan

Objective: To estimate the occurrence rate of sleep deprivation and to identify the environmental, staff-related and patient-related factors associated with SD among general ward patients of a tertiary care hospital in Pakistan.Methods: In a cross-sectional study, a pre-tested questionnaire was administered to 108 patients admitted into the general medical and general surgical wards of Aga Khan University Hospital, Karachi.Results: In all, 50 (46.3%) respondents felt deprived of adequate sleep in the hospital. Worry about illness disturbed the night-time sleep of 47 (43.5%) patients; most of these had SD (70%) (p \u3c 0.001). Other patients\u27 noise disturbed 31.5% of study subjects and a significant majority (68%) of these had SD (p = 0.003). Over 17% of study subjects reported cell phone\u27s ringing as a disturbing factor; more by those with SD (68%) compared to those with no SD (32%); again the difference was significant (p = 0.003). Physical discomfort and presence of cannula were reported as disturbing factors by 41.7% and 28.7% of the study subjects respectively but these were not significantly associated with SD.CONCLUSION: Our study revealed that sleep deprivation occurs commonly among general ward patients in tertiary care setting. Factors found to be associated with SD were amenable to modification to a greater extent

Robust estimation of bacterial cell count from optical density

Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals &lt;1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data

Advanced staged combustion system for power generation

To respond to the increasing market need for a new generation of plants with a substantial improvement in efficiency and a reduction in capital cost, the Institute of Gas Technology has developed an advanced staged, fluidized-bed combustion system concept. The staged fluidized-bed partial combustor produces the fuel gas at about 1500 F. The fuel gas, after particulate removal, is directed to a gas turbine followed by a steam cycle. Adequate sulfur capture and solids waste stabilization are attained by separating calcination, carbonization, and gasification/combustion steps in the staged fluidized beds. Intermediate gas cooling is avoided during the process to maximize the power production. The coal-to-electricity conversion efficiency of the system approaches 49 percent, which exceeds the efficiencies of the other emerging technologies

Advanced two-stage incineration: Research and development

IGT is currently developing a two-stage fluidized-bed/cyclonic agglomerating incineration system that is based on combining the fluidized-bed agglomeration/incineration and cyclonic combustion technologies, both of which have been developed individually at IGT over many years. This combination has resulted in a unique and extremely flexible incinerator for solid, liquid, and gaseous wastes. The system can operate over a wide range of conditions in the first stage, from low temperature (desorption) to high temperature (agglomeration), including gasification of high-Btu wastes. In the combined system, solid, liquid, and gaseous organic wastes are expected to be easily and efficiently destroyed (>99.99% destruction and removal efficiency (DRE)) while solid inorganic contaminants are expected to be contained within a glassy matrix, rendering them benign and suitable for disposal in an ordinary landfill. The development of the two-stage incinerator is a culmination of extensive research and development efforts on each stage of the incinerator. A variety of data obtained for both stages includes agglomeration of ash, incineration and reclamation of used blast grit and foundry sand, partial combustion of carbonaceous fuels, in-situ desulfurization, combustion of low-Btu gases, incineration of industrial wastewater, and incineration of carbon tetrachloride