Transient dynamics of nonlinear magneto-optical rotation

We analyze nonlinear magneto-optical rotation (NMOR) in rubidium vapor subjected to continuously-scanned magnetic field. By varying magnetic-field sweep rate, a transition from traditionally-observed dispersive-like NMOR signals (low sweep rate) to oscillating signals (higher sweep rates) is demonstrated. The transient oscillatory behavior is studied versus light and magnetic-field parameters, revealing a strong dependence of the signals on magnetic-sweep rate and light intensity. The experimental results are supported with density-matrix calculations, which enable quantitative analysis of the effect. Fitting of the signals simulated versus different parameters with a theoretically-motivated curve reveals presence of oscillatory and static components in the signals. The components depend differently on the system parameters, which suggests their distinct nature. The investigations provide insight into dynamics of ground-state coherence generation and enable application of NMOR in detection of transient spin couplings.Comment: 9 pages, 7 figures, Submitted to Physical Review

Bone marrow morphological features and diagnostic value in paediatric disseminated tuberculosis in the setting of increased HIV prevalence

Background. Disseminated tuberculosis (TB) is a life-threatening condition which is often a challenge to diagnose. When to use bone marrow biopsies to diagnose disseminated TB in paediatrics is always a dilemma, from both a clinical and laboratory perspective, as there are no clear guidelines. Our study primarily aims to evaluate the role of routine bone marrow biopsies, and to compare peripheral blood cultures to aspirate cultures in the diagnosis of disseminated TB, in a paediatric population at Tygerberg Hospital. In addition, we set out to assess the morphology of bone marrow biopsies in this study.Methods. A prospective study, consisting of 35 paediatric patients, was conducted from October 2007 to November 2008. Bone marrow aspirate and trephine biopsies were performed on all patients and examined. Granulomas with Ziehl-Neelsen (ZN) positivity were sought on the trephine biopsy for the presence of acid-fast bacilli (AFB).Results. Of the 35 children in this study, 25 were eventually diagnosed with TB on the basis of a multitude of clinical and laboratory parameters. The remaining 10 had alternative diagnoses. Peripheral blood TB cultures were positive in less than 1%. Bone marrow aspirate cultures were positive in less than 5%. Bone marrow trephine biopsies showed granulomas with ZN positivity in 11% of the 35 patients.Conclusion. Our results, generally, agree with the current evidence. Bone marrow biopsies in children should be performed if there is a strong clinical suspicion of disseminated TB, when no alternative non-invasive confirmatory test is available

Effect of oxidative stress on ABC transporters: contribution to epilepsy pharmacoresistance

Epilepsy is a neurological disorder affecting around 1%-2% of population worldwide and its treatment includes use of antiepileptic drugs to control seizures. Failure to respond to antiepileptic drug therapy is a major clinical problem and over expression of ATP-binding cassette transporters is considered one of the major reasons for pharmacoresistance. In this review, we have summarized the regulation of ABC transporters in response to oxidative stress due to disease and antiepileptic drugs. Further, ketogenic diet and antioxidants were examined for their role in pharmacoresistance. The understanding of signalling pathways and mechanism involved may help in identifying potential therapeutic targets and improving drug response

Genomic Diversity among Beijing and non-Beijing Mycobacterium tuberculosis Isolates from Myanmar

Background: The Beijing family of Mycobacterium tuberculosis is dominant in countries in East Asia. Genomic polymorphisms are a source of diversity within the M. tuberculosis genome and may account for the variation of virulence among M. tuberculosis isolates. Till date there are no studies that have examined the genomic composition of M. tuberculosis isolates from the high TB-burden country, Myanmar. Methodology/Principle Findings: Twenty-two M. tuberculosis isolates from Myanmar were screened on whole-genome arrays containing genes from M. tuberculosis H37Rv, M. tuberculosis CDC1551 and M. bovis AF22197. Screening identified 198 deletions or extra regions in the clinical isolates compared to H37Rv. Twenty-two regions differentiated between Beijing and non-Beijing isolates and were verified by PCR on an additional 40 isolates. Six regions (Rv0071-0074 [RD105], Rv1572-1576c [RD149], Rv1585c-1587c [RD149], MT1798-Rv1755c [RD152], Rv1761c [RD152] and Rv0279c) were deleted in Beijing isolates, of which 4 (Rv1572-1576c, Rv1585c-1587c, MT1798-Rv1755c and Rv1761c) were variably deleted among ST42 isolates, indicating a closer relationship between the Beijing and ST42 lineages. The TbD1 region, Mb1582-Mb1583 was deleted in Beijing and ST42 isolates. One M. bovis gene of unknown function, Mb3184c was present in all isolates, except 11 of 13 ST42 isolates. The CDC1551 gene, MT1360 coding for a putative adenylate cyclase, was present in all Beijing and ST42 isolates (except 1). The pks15/1 gene, coding for a putative virulence factor, was intact in all Beijing and non-Beijing isolates, except in ST42 and ST53 isolates. Conclusion: This study describes previously unreported deletions/extra regions in Beijing and non-Beijing M. tuberculosis isolates. The modern and highly frequent ST42 lineage showed a closer relationship to the hypervirulent Beijing lineage than to the ancient non-Beijing lineages. The pks15/1 gene was disrupted only in modern non-Beijing isolates. This is the first report of an in-depth analysis on the genomic diversity of M. tuberculosis isolates from Myanmar

Density functional theoretical studies on 2-methyl-4-chlorophenoxyacetic acid (MCPA)

135-142MCPA is a post-emergence herbicide for control of wild oats and annual grassy weeds found among several economically important crops. In the present work, the Eigen values and Eigen functions of the MCPA have been calculated using two basis sets of DFT. The Global DFT descriptors for the compound have also been calculated. The Fukui functions, local softness, and atomic charges for each center of MCPA have also been calculated It has been found that all the reactivity centers of MCPA are not equal in chemical reactivity. The differences in chemical reactivity of different sites have been investigated in detail in this work

An Impulse-C Hardware Accelerator for Packet Classification Based on Fine/Coarse Grain Optimization

Current software-based packet classification algorithms exhibit relatively poor performance, prompting many researchers to concentrate on novel frameworks and architectures that employ both hardware and software components. The Packet Classification with Incremental Update (PCIU) algorithm, Ahmed et al. (2010), is a novel and efficient packet classification algorithm with a unique incremental update capability that demonstrated excellent results and was shown to be scalable for many different tasks and clients. While a pure software implementation can generate powerful results on a server machine, an embedded solution may be more desirable for some applications and clients. Embedded, specialized hardware accelerator based solutions are typically much more efficient in speed, cost, and size than solutions that are implemented on general-purpose processor systems. This paper seeks to explore the design space of translating the PCIU algorithm into hardware by utilizing several optimization techniques, ranging from fine grain to coarse grain and parallel coarse grain approaches. The paper presents a detailed implementation of a hardware accelerator of the PCIU based on an Electronic System Level (ESL) approach. Results obtained indicate that the hardware accelerator achieves on average 27x speedup over a state-of-the-art Xeon processor

The sales lead black hole: On sales reps' follow-up of marketing leads

The sales lead black hole-the 70% of leads generated by marketing departments that sales representatives do not pursue-may result from competing demands on sales reps' time. Using the motivation-opportunity-ability framework, the authors consider factors that influence sales reps' pursuit (or lack thereof) of marketing and selfgenerated leads. The proportion of time that sales reps devote to marketing leads depends on organizational lead prequalification and managerial tracking processes (extrinsic motivation), as well as marketing lead volume (opportunity), and sales rep experience and performance (ability). Consistent with a person-situation framework, individual sales rep factors should also moderate the influence of organizational processes on lead follow-up. Data from 461 sales reps employed by four firms confirm that as sales reps' experience increases, their responses to managerial tracking of lead follow-up and marketing lead volume decrease; responses to the quality of the lead prequalification process increase. As sales reps' performance improves, their response to the volume of marketing leads increases, but their response to managerial tracking decreases. The interplay of individual sales reps' abilities and organizational marketing and sales processes explains differences in sales reps' follow-up of marketing leads.' © 2013, American Marketing Association

Franchise Partnership And International Expansion: A Conceptual Framework And Research Propositions

Although academic research has provided tremendous insights about the organizational form of franchising, considerable work remains with regard to understanding the critical factors that enable international franchise expansion and performance. The authors advance the argument that a franchise relationship is essentially an entrepreneurial partnership, and that this partnership influences the speed, scale, and scope of franchise expansion into international markets. In the proposed conceptual model, the authors detail the links among the franchise partnership, international expansion, and franchise system performance