57 research outputs found
Improved Genetic and Simulating Annealing Algorithms to Solve the Traveling Salesman Problem Using Constraint Programming
The Traveling Salesman Problem (TSP) is an integer programming problem that falls into the category of NP-Hard problems. As the problem become larger, there is no guarantee that optimal tours will be found within reasonable computation time. Heuristics techniques, like genetic algorithm and simulating annealing, can solve TSP instances with different levels of accuracy. Choosing which algorithm to use in order to get a best solution is still considered as a hard choice. This paper suggests domain reduction as a tool to be combined with any meta-heuristic so that the obtained results will be almost the same. The hybrid approach of combining domain reduction with any meta-heuristic encountered the challenge of choosing an algorithm that matches the TSP instance in order to get the best results
Type of High Secondary School (Governmental Vs Private) and Type of High Secondary School Certificate (Sudanese Vs Arabian): Do They Affect Learning Style?
Background: People differ in the way they perceive, process, store, and recall what they are attempting to learn. This study aimed to assess the learning styles among preclinical 1st year medical students and the influence of the type of high secondary school (governmental vs. private) and type of high secondary school certificate (Sudanese vs. Arabian) on learning style.Materials and Methods: A cross sectional institutional-based study was conducted at Al Neelain University, Khartoum State, Sudan. First year students of Medicine, Dentistry and Physiotherapy Faculties were enrolled. The VARK (Visual, Auditory, Read and write, and Kinesthetic) learning style hard copy questionnaire, © Copyright Version 7.8 (2014) held by VARK Learn Limited, Christchurch, New Zealand was administered following permission. Data were analyzed using Statistical Package for Social Sciences (SPSS) version 21.Results: Out of 320 students, 198 correctly completed VARK questionnaires, with mean age of 17.88 years (SD 1.52) and 74.2% were female students. About 59.6% were from governmental schools and 79.4% of the studied students had Sudanese High Secondary Certificates. About 64.1% demonstrated singular mode preference. Inferential statistics showed statistically significant difference between the learning styles and the type of secondary school whether governmental or private (P-value 0.005) while no statistically significant difference in relation to the type of high school certificate of the studied group (P-value 0.225).Conclusion: The type of secondary school whether governmental or private may affect learning style of medical students while student's gender, type of college, or type of high school certificate (whether Sudanese or Arabian) do not. More andlarger studies are encouraged.Key word: Learning modalities, VARK questionnaire, Unimodal preference, Medicaleducation, Sudan
Impact of center pivot irrigation system uniformity on growth of potato crop and residual soil nitrogen
Influence of soil chemical composition on electrical conductivity
156-161This paper presents the influences of soil chemical composition on electrical conductivity. Electrical conductivity of 150 samples from different locations of Pune district of Maharashtra State was measured. Chemical compositions such as organic carbon, nitrogen, potassium, phosphorous, sodium, calcium carbonate, iron, manganese, zinc and copper were measured. Pearson’s correlation coefficients studies were employed to highlight the influence of the chemical composition on the electrical conductivity. It had been observed that nitrogen, phosphorous, potassium, sodium and calcium carbonate have a significant influence on measured electrical conductivity values. Whereas there had een very low correlation with the organic carbon, iron, manganese, zinc and copper
The novel dual PI3K/mTOR inhibitor NVP-BGT226 displays cytotoxic activity in both normoxic and hypoxic hepatocarcinoma cells
Hepatocellular carcinoma (HCC) is one of the most common lethal human malignancies worldwide and its advanced status is frequently resistant to conventional chemotherapeutic agents and radiation. We evaluated the cytotoxic effect of the orally bioavailable dual PI3K/mTOR inhibitor, NVP-BGT226, on a panel of HCC cell lines, since hyperactivated PI3K/Akt/mTOR signaling pathway could represent a biomolecular target for Small Inhibitor Molecules in this neoplasia. We analyzed the drug activity in both normoxia and hypoxia conditions, the latter playing often a relevant role in the induction of chemoresistance and angiogenesis.
In normoxia NVP-BGT226 caused cell cycle arrest in the G0/G1 phase of the cell cycle, induced apoptosis and autophagy at low concentrations. Interestingly the drug inactivated p-Akt and p-S6 at < 10 nM concentration.
In hypoxia NVP-BGT226 maintained its cytotoxic efficacy at the same concentration as documented by MTT assays and Western blot analysis. Moreover, the drug showed in hypoxia inhibitory properties against angiogenesis by lowering the expression of the transcription factor HIF-1α and of VEGF.
Our results indicate that NVP-BGT226 has a potent cytotoxic effect on HCC cell lines also in hypoxia condition, thus emerging as a potential candidate for cancer treatment in HCC targeted therap
Coexistence of HBsAg/Anti-HBs and HBeAg/Anti-HBe in Sudanese Patients with Chronic Hepatitis B Virus Infection: A Cross-Sectional Study
Background: Seroconversion of hepatitis B surface antigen (HBsAg) to hepatitis B surface antibody (anti-HBs) is a recognized goal of HBV therapy. This dynamic transition responsible for the coexistence of HBsAg and anti-HBs is rarely detected in clinical cases. However, with vaccination and the use of various antiviral drugs, as well as the development of new medical technologies, recognizing the coexistence of HBsAg and anti-HBs has become more common. In addition, mutations in viral genomes, immune status, and human genetic factors may also contribute to such coexistence. The current study was designed to determine the prevalence of the coexistence of HBsAg and anti-HBs and HBeAg and anti-HBe in CHB patients in Sudan.
Methods and Results: This was a descriptive cross-sectional study conducted in Khartoum state from November 2018 to January 2019. The study included 70 HBV-infected patients who were positive for HBsAg for more than six months. Blood samples were tested for HBsAg/Anti-HBs and HBeAg/Anti-HBe using Commercial ELISA Kits (Foresight, United Kingdom) and (PRECHEK, USA). Demographic data were collected using a structured questionnaire, and any antiviral agent and laboratory results were also recorded for each participant. The current study showed that one case (1.4%) was reactive for the coexistence of HBsAg/HBsAb and two cases (2.8%) for the coexistence of HBeAg/HBeAb. There was no statistical difference between the coexistence of HBsAg/HBsAb and HBeAg/HBeAb with age, gender, residence, and treatment status.
Conclusion: Our study indicates that the frequencies of the coexistence of HBsAg/HBsAb and HBeAg/HBeAb among Sudanese patients with chronic HBV infection were low compared to previous studies in a different population
The PROVENT-C19 registry: A study protocol for international multicenter SIAARTI registry on the use of prone positioning in mechanically ventilated patients with COVID-19 ARDS
Background The worldwide use of prone position (PP) for invasively ventilated patients with COVID-19 is progressively increasing from the first pandemic wave in everyday clinical practice. Among the suggested treatments for the management of ARDS patients, PP was recommended in the Surviving Sepsis Campaign COVID-19 guidelines as an adjuvant therapy for improving ventilation. In patients with severe classical ARDS, some authors reported that early application of prolonged PP sessions significantly decreases 28-day and 90-day mortality. Methods and analysis Since January 2021, the COVID19 Veneto ICU Network research group has developed and implemented nationally and internationally the "PROVENT-C19 Registry", endorsed by the Italian Society of Anesthesia Analgesia Resuscitation and Intensive Care. . .'(SIAARTI). The PROVENT-C19 Registry wishes to describe 1. The real clinical practice on the use of PP in COVID-19 patients during the pandemic at a National and International level; and 2. Potential baseline and clinical characteristics that identify subpopulations of invasively ventilated patients with COVID-19 that may improve daily from PP therapy. This web-based registry will provide relevant information on how the database research tools may improve our daily clinical practice. Conclusions This multicenter, prospective registry is the first to identify and characterize the role of PP on clinical outcome in COVID-19 patients. In recent years, data emerging from large registries have been increasingly used to provide real-world evidence on the effectiveness, quality, and safety of a clinical intervention. Indeed observation-based registries could be effective tools aimed at identifying specific clusters of patients within a large study population with widely heterogeneous clinical characteristics. Copyright
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