One dimensional M5-brane intersections

We study one dimensional intersections of M5 branes with M5 and M2 branes. On the worldvolume of the M5-brane, such an intersection appears as a string soliton. We study this worldvolume theory in two different regimes: 1) Where the worldvolume theory is formulated in flat space and 2) where the worldvolume theory is studied in the supergravity background produced by a stack of M5 (or M2) branes. In both cases, we study the corresponding string solitons, and find the most general BPS configuration consistent with the fraction of supersymmetries preserved. We argue that M5 and M2 brane intersections leave different imprints on the worldvolume theory of the intersecting probe brane, although geometrically they appear to be similar.Comment: 13 pages, LaTeX, references adde

Implementation of Nonlinear Controller to Improve DC Microgrid Stability: A Comparative Analysis of Sliding Mode Control Variants

Electricity generation from sustainable renewable energy sources is constantly accelerating due to a rapid increase in demand from consumers. This requires an effective energy management and control system to fulfil the power demand without compromising the system’s performance. For this application, a nonlinear barrier sliding mode controller (BSMC) for a microgrid formed with PV, a fuel cell and an energy storage system comprising a battery and supercapacitor working in grid-connected mode is implemented. The advantages of the BSMC are twofold: The sliding surface oscillates in the close vicinity of zero by adapting an optimal gain value to ensure the smooth tracking of power to its references without overestimating the gains. Secondly, it exhibits a noticeable robustness to variations and disturbance, which is the bottleneck of the problem in a grid-connected mode. The stability of the presented controllers was analyzed with the Lyapunov stability criterion. Moreover, a comparison of the BSMC with sliding mode and supertwisting sliding mode controllers was carried out in MATLAB/Simulink (2020b) with real PV experimental data. The results and the numerical analysis verify the effectiveness of the BSMC in regulating the DC bus voltage in the presence of an external disturbance under varying conventional load and environmental conditions

The influence of menopause on urinary incontinence in the women of the community: a cross-sectional study from North India

Background: Urinary incontinence is defined as the complaint of any involuntary loss of urine that is a social or hygienic problem.  Worldwide, over 200 million people are living with urinary incontinence and as the life expectancy of women is increasing, more number of women are bound to suffer from it. The aim of the present study is to find out the effect of menopause on the occurrence of Urinary Incontinence in women and to find out risk factors in post-menopausal women associated with Urinary Incontinence.Methods: It was a community based cross-sectional study involving post-menopausal women living in the urban and rural areas registered under Community Medicine, J.N. Medical College, Aligarh, India. A total of 530 women were taken for this study. Descriptive statistics as well as simple proportion were calculated with SPSS 20.0. Tests of significance and Binary Logistic regression analysis were used for analysis.Results: Significant differences were found in the association of Urinary Incontinence with increasing age groups and consequent years spent in menopause, rural area of residence, illiteracy, lower socio-economic class, inadequate housing standards, obesity, smoking, parity, history of hysterectomy, and co-morbidities such as Urinary Tract Infection and Pelvic organ prolapse.Conclusions: From a public health perspective, there is considerable opportunity to improve women's quality of life by increasing health education about urinary incontinence and its treatment by taking steps for life style modifications

Efficiency of microbial bio-agents as elicitors in plant defense mechanism under biotic stress: A review.

Numerous harmful microorganisms and insect pests have the ability to cause plant infections or damage, which is mostly controlled by toxic chemical agents. These chemical compounds and their derivatives exhibit hazardous effects on habitats and human life too. Hence, there's a need to develop novel, more effective and safe bio-control agents. A variety of microbes such as viruses, bacteria, and fungi possess a great potential to fight against phytopathogens and thus can be used as bio-control agents instead of harmful chemical compounds. These naturally occurring microorganisms are applied to the plants in order to control phytopathogens. Moreover, practicing them appropriately for agriculture management can be a way towards a sustainable approach. The MBCAs follow various modes of action and act as elicitors where they induce a signal to activate plant defense mechanisms against a variety of pathogens. MBCAs control phytopathogens and help in disease suppression through the production of enzymes, antimicrobial compounds, antagonist activity involving hyper-parasitism, induced resistance, competitive inhibition, etc. Efficient recognition of pathogens and prompt defensive response are key factors of induced resistance in plants. This resistance phenomenon is pertaining to a complex cascade that involves an increased amount of defensive proteins, salicylic acid (SA), or induction of signaling pathways dependent on plant hormones. Although, there's a dearth of information about the exact mechanism of plant-induced resistance, the studies conducted at the physiological, biochemical and genetic levels. These studies tried to explain a series of plant defensive responses triggered by bio-control agents that may enhance the defensive capacity of plants. Several natural and recombinant microorganisms are commercially available as bio-control agents that mainly include strains of Bacillus, Pseudomonads and Trichoderma. However, the complete understanding of microbial bio-control agents and their interactions at cellular and molecular levels will facilitate the screening of effective and eco-friendly bio-agents, thereby increasing the scope of MBCAs. This article is a comprehensive review that highlights the importance of microbial agents as elicitors in the activation and regulation of plant defense mechanisms in response to a variety of pathogens

A check list of opisthobranch snails of the Karachi coast

The check list deals with 44 species of opisthobranchs belonging to Cephalaspidea (12 species), Anaspidea (4 species), Sacoglossa (4 species), Notaspidea, (2 species) and Nudibranchia (21 species), collected from Pakistan coast of northern Arabian Sea

Development of a community of inquiry in online and blended learning contexts

AbstractThis paper discusses findings of a mixed method research project with the goal to study the development of a community of inquiry in online and blended learning environments. A graduate course delivered online and blended format was the focus of the study. Data was gathered from the Community of Inquiry Survey and transcript analysis of online discussions to explore the developmental differences on each presence (social, teaching and cognitive). The results showed: significant differences on social and cognitive presence between two course formats and higher perceptions of the presences in blended course

Glutamatergic activation of A1 and A2 noradrenergic neurons in the rat brain stem

Aim To analyze the effects of glutamatergic agonists and antagonists on the activation of the A1 and A2 noradrenergic neurons localized in caudal ventrolateral medulla and nucleus tractus solitarii, respectively. Methods Rats were injected with glutamatergic agonists – kainic acid, α-amino-3-hydroxy-5-methyl-4- isoxazolepropionic acid (AMPA), or N-methyl-D-aspartic acid (NMDA), and the brain sections were prepared for immunohistochemistry. Before agonist injections, antagonists – 6-cyano-7-nitroquinoxaline-2,3-dione or dizocilpine were administered. The expression of c-Fos, as the neuronal activation marker, and tyrosine hydroxylase (TH), as the marker of noradrenergic neurons was assessed with dual immunohistochemistry. The percentage of c-Fos-positive noradrenergic neurons relative to all TH-positive neurons in the respective areas of the brain stem was calculated. Results All three glutamatergic agonists significantly increased the number of the c-Fos-positive noradrenergic neurons in both the A1 and A2 area when compared with control animals. Kainic acid injection activated about 57% of TH-positive neurons in A1 and 40% in A2, AMPA activated 26% in A1 and 38% in A2, and NMDA 77% in A1 and 22% in A2. The injections of appropriate glutamatergic antagonists greatly decreased the number of activated noradrenergic neurons. Conclusion Our results suggest that noradrenergic neurons are regulated and/or activated by glutamatergic system and that these neurons express functional glutamate receptors

Challenges of providing timely feedback to Residents: Faculty perspectives

Objective To explore faculty\u27s perceptions of challenges in providing verbal feedback to the Residents and suggest ways to overcome the barriers. Methods As part of a larger study on feedback assessment, five focus group discussions were conducted at the Department of Medicine, Aga Khan University Hospital, Karachi, during faculty development workshops held from January to June 2010. Qualitative grounded theory was used to explore faculty perceptions of challenges in providing verbal feedback to the Residents. Results Of the 54 faculty members, 49(91%) participated. Four themes that emerged were \u27time constraint\u27 indicating high patient load; \u27faculty related issues\u27 indicating faculty\u27s apprehension about its own evaluation by Residents; \u27educational issues\u27 indicating that the importance of feedback was not emphasised; and \u27system and logistic issues\u27 indicating that the assessment form used for assessing Residents was ambiguous. Conclusion Work load of the faculty and the expectations with respect to patient care responsibilities may have an impact on the quality, timing, content and delivery of the feedback provided to the Residents

Intracranial Meningioma Diagnosed during Pregnancy Caused Maternal Death

Brain tumors are rarely diagnosed during pregnancy. Accelerated growth of intracranial meningiomas during pregnancy sometimes requires urgent surgical intervention. We describe a 41-year-old pregnant woman with severe neurological decompensation requiring immediate neurosurgery. Cesarean section resulted in maternal death. Meningioma diagnosed during a viable pregnancy should be managed according to the severity of maternal neurological symptoms and gestational age of pregnancy. Early intervention for intracranial tumors during pregnancy may save maternal and fetal lives