583 research outputs found

    Energy Efficient Disaggregated Servers for Future Data Centers

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    With the dawn of cloud computing, data centers’ power consumption has received increased attention. In this paper we evaluate the energy efficiency potential of exploiting the concept of Disaggregated Server (DS) design in data centers for efficient resource provisioning. A DS, is a new approach for future racks where servers are disaggregated and resources, such as processors, memory and IO ports are arranged in resource pools constructing processing pools, memory pools and IO pools. We developed a mixed integer linear programming (MILP) model for energy minimization of the virtual machine (VM) placement problem in data centres implementing DS approach. The results show that the average power savings are up to 49% for the different VM types considered

    Conservation Need for a Plant Species with Extremely Small Populations Linked to Ephemeral Streams in Adverse Desert Environments

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    Many thousands of tree species are declining in the world, for which conservation actions are urgent. This dramatic situation is particularly evident for trees closely related to freshwater ecosystems, considered the environments most threatened by global change. In extremely arid environments such as deserts, where the few plant species present are able to survive by exploiting the little water available, the situation is extremely critical. A representative case is Vachellia gerrardii subsp. negevensis, a tree with a wide distribution range but locally restricted to small and isolated populations. Knowledge about this tree is incomplete in Iraq and, to fill this gap, several surveys were conducted in the Al-Najaf desert over three years (2019-2021). In each locality where this species was found, several ecological and population parameters were recorded. Our results indicate that Vachellia gerrardii subsp. negevensis was restricted to a single population, fragmented into five subpopulations confined in extremely peculiar ecological niches. Several threats related to anthropogenic activities and climate change affect the population, causing a significant reduction in the population size combined with a continuous decline in habitat quality and number of mature plants. Despite this critical situation, there are no conservation measures for this species. The establishment of a national preserve or part would be important and constitutes the fundamental prerequisite for the conservation of multiple species

    Future Energy Efficient Data Centers With Disaggregated Servers

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    The popularity of the Internet and the demand for 24/7 services uptime is driving system performance and reliability requirements to levels that today's data centers can no longer support. This paper examines the traditional monolithic conventional server (CS) design and compares it to a new design paradigm: the disaggregated server (DS) data center design. The DS design arranges data centers resources in physical pools, such as processing, memory, and IO module pools, rather than packing each subset of such resources into a single server box. In this paper, we study energy efficient resource provisioning and virtual machine (VM) allocation in DS-based data centers compared to CS-based data centers. First, we present our new design for the photonic DS-based data center architecture, supplemented with a complete description of the architectural components. Second, we develop a mixed integer linear programming (MILP) model to optimize VM allocation for the DS-based data center, including the data center communication fabric power consumption. Our results indicate that, in DS data centers, the optimum allocation of pooled resources and their communication power yields up to 42% average savings in total power consumption when compared with the CS approach. Due to the MILP high computational complexity, we developed an energy efficient resource provisioning heuristic for DS with communication fabric (EERP-DSCF), based on the MILP model insights, with comparable power efficiency to the MILP model. With EERP-DSCF, we can extend the number of served VMs, where the MILP model scalability for a large number of VMs is challenging. Furthermore, we assess the energy efficiency of the DS design under stringent conditions by increasing the CPU to memory traffic and by including high noncommunication power consumption to determine the conditions at which the DS and CS designs become comparable in power consumption. Finally, we present a complete analysis of the communication patterns in our new DS design and some recommendations for design and implementation challenges

    Prevalence of Vaginal Candidiasis among Pregnant Women with Abnormal Vaginal Discharge in Maiduguri

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    BACKGROUND: Pregnancy represents a risk factor in the occurrence of vaginal candidiasis. OBJECTIVES: To determine the prevalence and clinical features associated with abnormal vaginal discharge and C. albicans infection in pregnant women.METHODS: High vaginal swab samples and data on epidemiological characteristics were collected from 400 pregnant women with complaints of abnormal vaginal discharge at booking clinic of University of Maiduguri Teaching Hospital. The data was analysed using SPSS 16.0 statistical software.RESULTS: The prevalence of abnormal vaginal discharge in pregnancy was 31.5%. The frequency of abnormal vaginal discharge was 183 (45.8%) among those aged 20-24 years, 291 (72.8%) in multipara, 223 (55.8%) in those with Primary education and 293 (73.2%) in unemployed. Vulval pruritus 300 (75.0%) was significantly related to abnormal vaginal discharge (P<0.001). The prevalence of C. albicans was 41%. The frequencies of Vulval itching, Dyspareunia and vulval excoriation among those with candidiasis were 151 (50.3%), 14 (56.0%) and 75 (75.0%) respectively (P<0.001). CONCLUSION: The prevalence of abnormal vaginal discharge in pregnancy was high in this study and C. albicans was the commonest cause. It is recommended that a pregnant woman complaining of abnormal vaginal discharge be assessed and Laboratory diagnosis done in order to give appropriate treatment. Erratum Note: Ibrahim SM, Mohammed B, Yahaya M, Audu BM, Ibrahim HA on the article ”Prevalence of VaginalCandidiasis among Pregnant Women with Abnormal Vaginal Discharge in Maiduguri” on Page Nig. J. Med2013. 138-142. Should read: Ibrahim SM, Bukar M, Mohammed Y, Audu BM, Ibrahim HM

    Gross hematuria as the presentation of an inguinoscrotal hernia: a case report

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    <p>Abstract</p> <p>Introduction</p> <p>Several complications have been reported with inguinal hernias. Although hematuria and flank pain, either as the presentation or as a complication of inguinal hernia, are infrequent, this condition may lead to the development of obstructive uropathy, which can have diverse manifestations.</p> <p>Case presentation</p> <p>A 71-year-old Iranian man with Persian ethnicity presented with new onset episodes of gross hematuria and left-sided flank pain. A physical examination revealed a large and non-tender inguinal hernia on his left side. An initial workup included an abdominal ultrasound, an intravenous pyelogram and cystoscopy, which showed left hydronephrosis and a bulging on the left-side of his bladder wall. On further evaluation, computed tomography confirmed that his sigmoid colon was the source of the pressure effect on his bladder, resulting in hydroureteronephrosis and hematuria. No tumoral lesion was evident. Herniorrhaphy led to the resolution of his signs and symptoms.</p> <p>Conclusion</p> <p>Our case illustrates a rare presentation of inguinal hernia responsible for gross hematuria and unilateral hydronephrosis. Urologic signs and symptoms can be caused by the content of inguinal hernias. They can also present as complications of inguinal hernias.</p

    Acute symptoms related to air pollution in urban areas: a study protocol

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    BACKGROUND: The harmful effects of urban air pollution on general population in terms of annoying symptoms are not adequately evaluated. This is in contrast to the hospital admissions and short term mortality. The present study protocol is designed to assess the association between the level of exposure to certain ambient air pollutants and a wide range of relevant symptoms. Awareness of the impact of pollution on the population at large will make our estimates of the pertinent covert burden imposed on the society more accurate. METHODS/DESIGN: A cross sectional study with spatial analysis for the addresses of the participants was conducted. Data were collected via telephone interviews administered to a representative sample of civilians over age four in the city. Households were selected using random digit dialling procedures and randomization within each household was also performed to select the person to be interviewed. Levels of exposure are quantified by extrapolating the addresses of the study population over the air pollution matrix of the city at the time of the interview and also for different lag times. This information system uses the data from multiple air pollution monitoring stations in conjunction with meteorological data. General linear models are applied for statistical analysis. DISCUSSION: The important limitations of cross-sectional studies on acute effects of air pollution are personal confounders and measurement error for exposure. A wide range of confounders in this study are controlled for in the statistical analysis. Exposure error may be minimised by employing a validated geographical information system that provides accurate estimates and getting detailed information on locations of individual participants during the day. The widespread operation of open air conditioning systems in the target urban area which brings about excellent mixing of the outdoor and indoor air increases the validity of outdoor pollutants levels that are taken as exposure levels

    Treatment outcomes of fixed-dose combination versus separate tablet regimens in pulmonary tuberculosis patients with or without diabetes in Qatar

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    Background: Tuberculosis is considered the second most common cause of death due to infectious agent. The currently preferred regimen for treatment of pulmonary tuberculosis (PTB) is isoniazid, rifampin, pyrazinamide, and ethambutol, which has been used either as separate tablets (ST) or as fixed-dose combination (FDC). To date, no studies have compared both regimens in Qatar. We aim to evaluate the safety and effectiveness of FDC and ST regimen for treating PTB, in addition to comparing safety and efficacy of FDC and ST regimens in patients with diabetes treated for TB. Methods: A retrospective observational study was conducted in two general hospitals in Qatar. Patients diagnosed with PTB received anti-tuberculosis medications (either as FDC or ST) administered by the nurse. Sputum smears were tested weekly. We assessed the time to negative sputum smear and incidence of adverse events among FDC and ST groups. Results: The study included 148 patients. FDC was used in 90 patients (61%). Effectiveness was not different between FDC and ST regimens as shown by mean time to sputum conversion (29.9 ± 18.3 vs. 35.6 ± 23 days, p = 0.12). Similarly, there was no difference in the incidence of adverse events, except for visual one that was higher in ST group. Among the 33 diabetic patients, 19 received the FDC and had faster sputum conversion compared to those who received ST (31 ± 12 vs. 49.4 ± 30.9 days, p = 0.05). Overall, diabetic patients needed longer time for sputum conversion and had more hepatotoxic and gastric adverse events compared to non-diabetics. Conclusion: ST group had higher visual side effects compared to FDC. FDC may be more effective in diabetic patients; however, further studies are required to confirm such finding.PublishedN/

    Can Bcl-XL expression predict the radio sensitivity of Bilharzial-related squamous bladder carcinoma? a prospective comparative study

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    <p>Abstract</p> <p>Background</p> <p>Local pelvic recurrence after radical cystectomy for muscle invasive bilharzial related squamous cell carcinoma accounts for 75% of treatment failures even in organ confined tumors. Despite the proven value of lymphadenectomy, up to 60% of patients undergoing cystectomy do not have it. These factors are in favor of adjuvant radiotherapy reevaluation. objectives: to evaluate the effect of adjuvant radiotherapy on disease free survival in muscle invasive bilharzial related squamous cell carcinoma of the urinary bladder and to test the predictability of radio-sensitivity using the anti apoptotic protein Bcl-XL.</p> <p>Methods</p> <p>The study prospectively included 71 patients, (47 males, 24 females) with muscle invasive bilharzial related squamous cell carcinoma of the bladder (Stage pT2a-T3N0-N3M0) who underwent radical cystectomy in Assiut university hospitals between January 2005 and December 2006. Thirty eight patients received adjuvant radiotherapy to the pelvis in the dose of 50Gy/25 fractions/5 weeks (Group 1), while 33 patients did not receive adjuvant radiotherapy (group 2). Immunohistochemical characterization for bcl-xL expression was done. Follow up was done every 3 months for 12 to 36 months with a mean of 16 ± 10 months. All data were analyzed using SPSS version 16. Three years cumulative disease free survival was calculated and adjusted to Bcl-XL expression and side effects of the treatment were recorded.</p> <p>Results</p> <p>The disease free cumulative survival was 48% for group 1 and 29% for group 2 (log rank p value 0.03). The multivariate predictors of tumor recurrence were the positive Bcl-XL expression (odd ratio 41.1, 95% CI 8.4 - 102.3, p < 0.0001) and radiotherapy (odd ratio 0.19, 95% CI 0.05 - 0.78, p < 0.02). With Cox regression, the only independent multivariate predictor of radio-sensitivity was the Bcl-XL expression with odd ratio 4.6 and a p value < 0.0001. All patients tolerated the treatment with no life threatening or late complications during the period of follow up.</p> <p>Conclusions</p> <p>Adjuvant radiotherapy for muscle invasive bilharzial related squamous cell carcinoma of the urinary bladder has potential effectiveness and minor side effects. Moreover, Bcl-XL expression is a valuable tool for predicting those who might not respond to this adjuvant treatment.</p

    Muscle invasive bladder cancer in Upper Egypt: the shift in risk factors and tumor characteristics

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    <p>Abstract</p> <p>Background</p> <p>In Egypt, where bilharziasis is endemic, bladder cancer is the commonest cancer in males and the 2<sup>nd </sup>in females; squamous cell carcinoma (SCC) is the commonest type found, with a peculiar mode of presentation. The aim of this study is to identify and rank the risk factors of muscle invasive bladder cancer (MIBC) in Upper Egypt and describe its specific criteria of presentation and histopathology.</p> <p>Methods</p> <p>This is an analytical, hospital based, case controlled study conducted in south Egypt cancer institute through comparing MIBC cases (n = 130) with age, sex and residence matched controls (n = 260) for the presence of risk factors of MIBC. Data was collected by personal interview using a well designed questionnaire. Patients' records were reviewed for histopathology and Radiologic findings.</p> <p>Results</p> <p>The risk factors of MIBC were positive family history [Adjusted odds ratio (AOR) = 7.7], exposure to pesticides [AOR = 6.2], bladder stones [AOR = 5], consanguinity [AOR = 3.9], recurrent cystitis [AOR = 3.1], bilharziasis [odds ratio (OR) = 5.8] and smoking [OR = 5.3]. SCC represented 67.6% of cases with burning micturition being the presenting symptom in 73.8%.</p> <p>Conclusion</p> <p>MIBC in Upper Egypt is usually of the SCC type (although its percentage is decreasing), occurs at a younger age and presents with burning micturition rather than hematuria. Unlike the common belief, positive family history, parents' consanguinity, exposure to pesticides and chronic cystitis seem to play now more important roles than bilharziasis and smoking in the development of this disease in this area.</p

    Individuals with Le(a+b−) Blood Group Have Increased Susceptibility to Symptomatic Vibrio cholerae O1 Infection

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    Cholera remains a severe diarrheal disease, capable of causing extensive outbreaks and high mortality. Blood group is one of the genetic factors determining predisposition to disease, including infectious diseases. Expression of different Lewis or ABO blood group types has been shown to be associated with risk of different enteric infections. For example, individuals of blood group O have a higher risk of severe illness due to V. cholerae compared to those with non-blood group O antigens. In this study, we have determined the relationship of the Lewis blood group antigen phenotypes with the risk of symptomatic cholera as well as the severity of disease and immune responses following infection. We show that individuals expressing the Le(a+b−) phenotype were more susceptible to symptomatic cholera, while Le(a–b+) expressing individuals were less susceptible. Individuals with the Le(a–b−) blood group had a longer duration of diarrhea when infected, required more intravenous fluid replacement, and had lower plasma IgA antibody responses to V. cholerae LPS on day 7 following infection. We conclude that there is an association between the Lewis blood group and the risk of cholera, and that this risk may affect the outcome of infection as well as possibly the efficacy of vaccination
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