Global quantum discord and von Neumann entropy in multipartite two-level atomic systems

We have computed the global quantum discord and von Neumann entropy of multipartite two-level atomic systems interacting with a single-mode Fock field. We use Tavis-Cumming model. We have explored how quantum correlations and quantum entanglement evolve with time in such systems. The quantum system is prepared initially in a mixed state and different parameters are varied to see how they affect the information processing in the system. The dynamical character of the global quantum discord and von Neumann entropy show an interplay between classical and non-classical correlations. Photons in this model play an important role to assist the global quantum discord and von Neumann entropy and we observed that the effects of the field on the global quantum discord and von Neumann entropy reside in the time evolution of the system indicating that both atom and field states have become entangled. The global quantum discord is assisted in a non-linear fashion with the number of photons in the system. The global quantum discord and von Neumann entropy show linear behavior with each other in the dynamics of the system. The effects of intrinsic decoherence on the dynamics of the global quantum discord and von Neumann entropy are also studied. We have extrapolated the results for a large photon number on the system. We have studied the effect of the change in the size of the system on the maximum value of global quantum discord and von Neumann entropy and we have estimated the scaling coefficients for this behavior

Detection and Antibiotic Susceptibility Pattern of Biofilm Producing Gram Positive and Gram Negative Bacteria Isolated From a Tertiary Care Hospital of Pakistan

Microorganisms adhere to non-living material or living tissue, and form biofilms made up of extracellular polymers/slime. Biofilm-associated microorganisms behave differently from free-floating bacteria with respect to growth rates and ability to resist antimicrobial treatments and therefore pose a public health problem. The objective of this study is to detect the prevalence of biofilm producers among Gram positive and Gram negative bacteria isolated from clinical specimens, and to study their antimicrobial susceptibility pattern. The study was carried out from October 2009 to March 2010, at the Department of Microbiology, Army Medical College/ National University of Sciences and Technology (NUST), Rawalpindi, Pakistan. Clinical specimens were received from various wards of a tertiary care hospital. These were dealt by standard microbiological procedures. Gram positive and Gram negative bacteria isolated were subjected to biofilm detection by congo red agar method (CRA). Antimicrobial susceptibility testing of those isolates, which showed positive results (slime production), was done according to the Kirby-Bauer disc diffusion technique. A total of 150 isolates were tested for the production of biofilm/slime. Among them, 81 isolates showed positive results. From these 81, 51 were Gram positive and 30 were Gram negative. All the 81(54%) slime producers showed reduced susceptibility to majority of antibiotics. Bacterial biofilms are an important virulence factor associated with chronic nosocomial infection. Detection of biofilm forming organisms can help in appropriate antibiotic choice

Median survival time of patients after transcatheter chemo-embolization for hepatocellular carcinoma

Objective: To determine the effect on survival after transarterial chemoembolization (TACE) in patients with unresectable hepatocellular carcinoma (HCC).Design: Longitudinal cohort study.PLACE AND DURATION OF STUDY: Radiology Department, The Aga Khan University Hospital, Stadium Road, Karachi, from December 1997 to September 2005.PATIENTS AND Methods: Patients undergoing TACE procedure for HCC were prospectively followed. Fortythree patients were enrolled from December 1997 to March 2003 in the study and subjected to chemoembolization therapy. Eight out of 43 patients were excluded from the study, who lost to follow-up. All the patients were followed till their death. Median and mean survival were calculated.Results: The median survival of these 35 patients was 410 days (13.6 months), with 95% confidence interval (236 days lower bound and 536 days upper bound). Mean survival time was 603 days (20.1 months) with 95% confidence interval (394 days lower bound and 812 days upper bound). There was significant difference in mean survival time (in days) by Child s Pugh class (chi(2) = 12.384; df=2, p-value=0.002).CONCLUSION: The study showed that TACE is an effective palliative treatment. TACE increases the median survival time

Evaluation of combined disc method for the detection of metallo-β-lactamase producing Gram negative bacilli

Aims: Infections due to metallo-β-lactamase (MBL) producing Gram negative rods are a cause of high mortality and morbidity. Early detection by an economical and accurate method may improve patient outcome. This study was aimed to evaluate the diagnostic accuracy of combined disc method for MBL detection by comparing it with MBL-Etest.Methodology and Results: This cross-sectional, validation study was carried out in the Department of Microbiology, Army Medical College, National University of Sciences and Technology, Rawalpindi, over a period of six months. A total of 52 non-duplicate Gram-negative rods isolated from the routine clinical specimens and found resistant to meropenem/imipenem on Kirby Bauer Disc Diffusion method were subjected to two tests for metallo-β-lactamase detection. One was combined Disc test using imipenem with Ethylene Diamine Tetraacetic Acid (EDTA), where a strain showing an increase in zone of inhibition of combined disc of ≥ 7 mm as compared to imipenem alone, was considered as MBL producer and the other one was MBL-Etest for which results were interpreted as per manufacturer’s guidelines. Combined disc method for MBL detection was found to have a sensitivity, specificity, positive predictive value, negative predictive value and accuracy of 97.5%, 100%, 100%, 92% and 98%.Conclusion, Significance and Impact of study: Combined disc method is an economical and reliable method for metallo-β-lactamase detection which can be used routinely in any laboratory

Do stock markets play a role in determining COVID-19 economic stimulus? A cross-country analysis

This paper makes an innovative contribution to the extant literature by analysing the determinants of economic stimulus packages implemented by governments in response to the COVID-19 pandemic. In particular, we explore whether stock market declines observed in many countries can predict the size of COVID-19 stimulus packages. Moreover, we explore whether a country's level of income can augment the underlying relationship between stock market declines and stimulus packages. The findings reveal that a larger stock market decline results in a larger stimulus package; however, this effect is only observed in countries that have an income level greater than the mean and/or median per capita gross domestic product (GDP). Moreover, our results show that monetary policy is more responsive to a stock market decline than fiscal policy. Thus, our results underscore the importance of international donor agencies such as the World Bank and International Monetary Fund (IMF) in supporting less affluent countries in coping with the adverse impacts of the COVID-19 pandemic on their economies

Determination of drivers of stock-out performance of retail stores using data mining techniques

Includes bibliographical references (leaves 66-67).Thesis (M. Eng. in Logistics)--Massachusetts Institute of Technology, Engineering Systems Division, 2008.This research applies data mining techniques to give a picture of the interaction of performance variables such as between stock-outs and store attributes, and stock-outs and other variables including store sales, income and demographic data, as well as various aspects of inventory management data. This research uses three data mining techniques: multiple ordinary-least-squares (OLS) regression, logistic regression and data clustering. The first part of the research evaluates how the effect of stock-outs at the distribution center (DC) level impacts the downstream sales at the store-level. Using multiple regression techniques, it was observed that stock-outs at the distribution center level have a detrimental impact on the sales at the retail store level. The second part of the project focuses on understanding the relationships of store stock-out performance to various drivers. The variables that were determined to be drivers of store performance include income level of the area, demographic profile, years the store has been in operation, day of the week delivery from distribution center, distance of store from the distribution center and average inventory-on-hand. Using data clustering techniques, worse performing and good performing clusters of stores were identified. The two worse performing clusters were 'Low-Income, Newer' stores and 'Newer, Further from DC' stores. The three good performing clusters were 'High-Income, High-Inventory' stores, 'Closer to DC, Older' Stores and 'High-Income, Smaller' stores.by Khalid Usman.M.Eng.in Logistic