The Berkovits Complex and Semi-free Extensions of Koszul Algebras

In his extension of W. Siegel's ideas on string quantization, N. Berkovits made several observations which deserve further study and development. Indeed, interesting accounts of this work have already appeared in the mathematical literature and in a different guise due to Avramov. In this paper we bridge between these three approaches, by providing a complex that is useful in the calculation of some homologies.Comment: 15 page

The Berkovits Complex and Semi-free Extensions of Koszul Algebras

Acknowledgments. — The first author was partially supported by Spanish Government grants MTM2010-15831, MTM2010-20692, MTM2012-38122- C03-01, MTM2013-42178-P and MTM2015-69135-P and Catalan Government grants SGR1092-2009 and SGR634-2014, and the fourth author by MTM2010-15831 and MTM2013-42178-P. All the authors visited the Max Planck Institute while working on this project and are grateful to the Institute for excellent working conditions. The authors also thank to L.A. Bokut, A. Losev and M. Movshev for very useful discussions and advice, and A. Conca and S. Iyengar for pointing us to Avramov’s commutative algebra constructions in [2]. We are also grateful to the referee for pointing out an error in [8, Theorem 4.4.1], which we initially used to construct the smaller complex for a larger class of algebras. Of course we also are very grateful to Vadim Schechtman with whom this project originally was started and to whom we dedicate it with our best wishes.Peer reviewedPostprin

Mini-craniotomy under local anesthesia for chronic subdural hematoma: An effective choice for elderly patients and for patients in a resource-strained environment

Background: Mini-craniotomy for chronic subdural hematoma (CSDH) is associated with lower rates of recurrence. However, the procedure is performed mostly with the patient under general anesthesia (GA) and therefore frequently requires an intensive care unit (ICU) facility, especially in the elderly population. Because of the unavailability of ICU beds, and to avoid GA, we started to perform this procedure with the patient under local anesthesia (LA).Materials and methods: This was a retrospective medical chart review conducted in the section of Neurosurgery at the Aga Khan Hospital in Karachi, Pakistan. The study duration was 1 year. We included patients aged 55 years or older undergoing surgery for CSDH. Clinical characteristics, hospital stay, and recurrence rates were compared between 2 groups, local versus general anesthesia.Results: Thirty-five patients underwent mini-craniotomy for CSDH in the study period. Sixteen patients underwent mini-craniotomy under LA versus 19 patients for GA. Median age for the LA group was 67 years compared with 70 years in the GA group. Four patients from the LA group experienced postoperative complications versus 7 from the GA group. Only one patient in the LA group required an ICU bed in the postoperative period. There was no recurrence in LA group. The overall recurrence was 2.86%.Conclusions: Mini-craniotomy for CSDH under LA is an equally effective procedure compared with mini-craniotomy under GA. In addition, it minimizes the risks of GA in the elderly population and obviates the need of a postoperative ICU bed. It also reduces operative time and hospital stay as compared with GA

Antimicrobial Activity of Plant Extracts against Bacillus Subtilis, Staphylococcus Aureus and Escherichia Coli

Abstract: Local herbs have many potential that may be active with antimicrobial activity. A screening was conducted with 11 species of herbs collected in UiTM Pahang Forest Reserve. Epipremnum sp., Zingiber sp. Tetracera indica, Tectaria crenata, Piper stylosum, Homalomena propinque, Goniothalamus sp., Elephantopus scaber, Mapania patiolale, Melastoma sp., Stemona tuberosa, Phullagathis rotundifolia, Thotea grandifolia and Smilax sp. were extracted with methanol to obtain their crude. The agar diffusion method using blank disc of 6 mm diameter were loaded with 1000 μg/mL of methanol crude and applied to the inoculate plate was used to assess the antimicrobial activity against two gram positive bacteria (Bacillus subtilis and Staphylococcus aeureus) and one gram negative bacteria (Escherichia coli). The results evaluated as the diameter of the inhibition zone of microbial growth, showed that all the extracts were active against gram-positive bacteria and gramnegative bacteria. The extract of Stemona tuberosa was found to be the most active against the E. coli and S. aeureus while Piper stylosum active against B. subtilis

Ethnic differences in out-of-hospital cardiac arrest among Middle Eastern Arabs and North African populations living in Qatar

Aims: There are very few studies comparing epidemiology and outcomes of out-of-hospital cardiac arrest (OHCA) in different ethnic groups. Previous ethnicity studies have mostly determined OHCA differences between African American and Caucasian populations. The aim of this study was to compare epidemiology, clinical presentation, and outcomes of OHCA between the local Middle Eastern Gulf Cooperation Council (GCC) Arab and the migrant North African populations living in Qatar. Methods: This was a retrospective cohort study of Middle Eastern GCC Arabs and migrant North African patients with presumed cardiac origin OHCA resuscitated by Emergency Medical Services (EMS) in Qatar, between June 2012 and May 2015. Results: There were 285 Middle Eastern GCC Arabs and 112 North African OHCA patients enrolled during the study period. Compared with the local GCC Arabs, univariate analysis showed that the migrant North African OHCA patients were younger and had higher odds of initial shockable rhythm, pre-hospital interventions (defibrillation and amioderone), pre-hospital scene time, and decreased odds of risk factors (hypertension, respiratory disease, and diabetes) and pre-hospital response time. The survival to hospital discharge had greater odds for North African OHCA patients which did not persist after adjustment. Multivariable logistic regression showed that North Africans were associated with lower odds of diabetes (OR 0.48, 95% CI 0.25–0.91, p = 0.03), and higher odds of initial shockable rhythm (OR 2.86, 95% CI 1.30–6.33, p = 0.01) and greater scene time (OR 1.02 95% CI 1.0–1.04, p = 0.02). Conclusions: North African migrant OHCA patients were younger, had decreased risk factors and favourable OHCA rhythm and received greater ACLS interventions with shorter pre-hospital response times and longer scene times leading to better survival.Peer reviewedFinal Accepted Versio

Ethnic differences in out-of-hospital cardiac arrest among Middle Eastern Arabs and North African populations living in Qatar

Peer reviewe

A bibliometric analysis on the productivity of opioid research in Malaysia

INTRODUCTION Opioid analgesics have been widely used for the treatment of pain. In the USA, it was reported that increase in opioid prescribing is parallel with the increase of opioid use disorders such as misuse, abuse and opioids overdose related death. Little is known about the opioid situation and its related research in Malaysia. OBJECTIVES This bibliometric study provided an overview on the productivity of opioid research in Malaysia. METHOD All original articles on opioid research in Malaysia from 2006 to 2018 were included. The articles were retrieved from databases such as Scopus, Science Direct and PubMed using search terms such as opioids, methadone, fentanyl, oxycodone and morphine. Growth of publications, number of citations journals, geographical distribution and issues addressed in the publications were analysed and presented using standard bibliometric indicators. RESULTS A total of 78 research articles on opioids published between 2006-2018 were identified. The relative growth rate of publications (RGR) during the study period was 12.24%. The most common issue studied was the methadone maintenance therapy. Most articles were published in the indexed journals (98.72%) and the predominant journal was the Drug and Alcohol Dependence journal (11.54%). Almost all articles were multi-authored (99%) and the articles on buprenorphine and naltrexone reported the highest citations of 85. CONCLUSION This study showed that the focus of opioid research in Malaysia was in the field of methadone maintenance therapy. Research evaluating opioids in pain management particularly in patients with non-cancer pain is limited and require further exploration

A Novel Coupled Reaction-Diffusion System for Explainable Gene Expression Profiling

Machine learning (ML)-based algorithms are playing an important role in cancer diagnosis and are increasingly being used to aid clinical decision-making. However, these commonly operate as ‘black boxes’ and it is unclear how decisions are derived. Recently, techniques have been applied to help us understand how specific ML models work and explain the rational for outputs. This study aims to determine why a given type of cancer has a certain phenotypic characteristic. Cancer results in cellular dysregulation and a thorough consideration of cancer regulators is required. This would increase our understanding of the nature of the disease and help discover more effective diagnostic, prognostic, and treatment methods for a variety of cancer types and stages. Our study proposes a novel explainable analysis of potential biomarkers denoting tumorigenesis in non-small cell lung cancer. A number of these biomarkers are known to appear following various treatment pathways. An enhanced analysis is enabled through a novel mathematical formulation for the regulators of mRNA, the regulators of ncRNA, and the coupled mRNA–ncRNA regulators. Temporal gene expression profiles are approximated in a two-dimensional spatial domain for the transition states before converging to the stationary state, using a system comprised of coupled-reaction partial differential equations. Simulation experiments demonstrate that the proposed mathematical gene-expression profile represents a best fit for the population abundance of these oncogenes. In future, our proposed solution can lead to the development of alternative interpretable approaches, through the application of ML models to discover unknown dynamics in gene regulatory systems