440 research outputs found

    A comparative study for estimating the parameters of the second order moving average process

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    EnMoving Average process is a representation of a time series written as a finite linear combination of uncorrelated random variables. Our main interest is to compare a classical estimation method; namely Exact Maximum Likelihood Estimation (EMLE) with the Generalized Maximum Entropy (GME) approach for estimating the parameters of the second order moving average processes. In this paper, in applying EMLE we have to find the exact likelihood function through deriving the probability density function of the series. Differentiating the function with respect to the parameters, we can obtain the exact maximum likelihood estimates. On the other hand, the idea of GME is to write the unknown parameters and error terms as the expected value of some proper probability distributions defined over some supports. We carry a simulation study to compare between the presented estimation techniques

    A Survey of Limitations and Enhancements of the IPv6 Routing Protocol for Low-power and Lossy Networks: A Focus on Core Operations

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    Driven by the special requirements of the Low-power and Lossy Networks (LLNs), the IPv6 Routing Protocol for LLNs (RPL) was standardized by the IETF some six years ago to tackle the routing issue in such networks. Since its introduction, however, numerous studies have pointed out that, in its current form, RPL suffers from issues that limit its efficiency and domain of applicability. Thus, several solutions have been proposed in the literature in an attempt to overcome these identified limitations. In this survey, we aim mainly to provide a comprehensive review of these research proposals assessing whether such proposals have succeeded in overcoming the standard reported limitations related to its core operations. Although some of RPL’s weaknesses have been addressed successfully, the study found that the proposed solutions remain deficient in overcoming several others. Hence, the study investigates where such proposals still fall short, the challenges and pitfalls to avoid, thus would help researchers formulate a clear foundation for the development of further successful extensions in future allowing the protocol to be applied more widely

    Decreasing Prevalence of the Full Metabolic Syndrome but a Persistently High Prevalence of Dyslipidemia among Adult Arabs

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    A decade has passed since metabolic syndrome (MetS) was documented to be highly prevalent in the kingdom of Saudi Arabia. No follow-up epidemiologic study was done. This study aims to fill this gap. In this cross-sectional, observational study, a total of 2850 randomly selected Saudi adults aged 18–55 years were recruited. Subjects' information was generated from a database of more than 10,000 Saudi citizens from the existing Biomarkers Screening in Riyadh Program (RIYADH Cohort), Saudi Arabia. Anthropometrics included body mass index (BMI), blood pressure, as well as waist and hip circumferences. Fasting blood glucose and lipid profile were determined using routine laboratory procedures. The definition of ATP-III (NHANES III) was used for the diagnosis of the full MetS. The overall prevalence of complete MetS was 35.3% [Confidence-Interval (CI) 33.5–37.01]. Age-adjusted prevalence according to the European standard population is 37.0%. Low HDL-cholesterol was the most prevalent of all MetS risk factors, affecting 88.6% (CI 87.5–89.7) and hypertriglyceridemia the second most prevalent, affecting 34% (CI 32.3–35.7) of the subjects. The prevalence of the full MetS decreased from previous estimates but remains high, while dyslipidemia remains extremely high, affecting almost 90% of middle-aged Arabs. Screening for dyslipidemia among Saudi adults is warranted, especially among those most at risk. Scientific inquiry into the molecular causes of these manifestations should be pursued as a first step in the discovery of etiologic therapies

    Increased circulating ANG II and TNF-α represents important risk factors in obese Saudi adults with hypertension irrespective of diabetic status and BMI

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    Central adiposity is a significant determinant of obesity-related hypertension risk, which may arise due to the pathogenic inflammatory nature of the abdominal fat depot. However, the influence of pro-inflammatory adipokines on blood pressure in the obese hypertensive phenotype has not been well established in Saudi subjects. As such, our study investigated whether inflammatory factors may represent useful biomarkers to delineate hypertension risk in a Saudi cohort with and without hypertension and/or diabetes mellitus type 2 (DMT2). Subjects were subdivided into four groups: healthy lean controls (age: 47.9±5.1 yr; BMI: 22.9±2.1 Kg/m2), non-hypertensive obese (age: 46.1±5.0 yr; BMI: 33.7±4.2 Kg/m2), hypertensive obese (age: 48.6±6.1 yr; BMI: 36.5±7.7 Kg/m2) and hypertensive obese with DMT2 (age: 50.8±6.0 yr; BMI: 35.3±6.7 Kg/m2). Anthropometric data were collected from all subjects and fasting blood samples were utilized for biochemical analysis. Serum angiotensin II (ANG II) levels were elevated in hypertensive obese (p<0.05) and hypertensive obese with DMT2 (p<0.001) compared with normotensive controls. Systolic blood pressure was positively associated with BMI (p<0.001), glucose (p<0.001), insulin (p<0.05), HOMA-IR (p<0.001), leptin (p<0.01), TNF-α (p<0.001) and ANG II (p<0.05). Associations between ANG II and TNF-α with systolic blood pressure remained significant after controlling for BMI. Additionally CRP (p<0.05), leptin (p<0.001) and leptin/adiponectin ratio (p<0.001) were also significantly associated with the hypertension phenotype. In conclusion our data suggests that circulating pro-inflammatory adipokines, particularly ANG II and, TNF-α, represent important factors associated with a hypertension phenotype and may directly contribute to predicting and exacerbating hypertension risk

    An efficient IoT-based smart water meter system of smart city environment

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    Water is a precious need of our lives. Due to the rapid population and urbanization, water usage monitoring is a significant problem facing our society. One solution is to control, analyze, and reduce the water consumption of the houses. The emerging of the Internet of Things (IoT) concept lately in our lives has offered the opportunity to establish water usageefficient smart devices, systems and applications for buildings and cities. Many studies have suggested designing an IoT-based smart meter system; however, the IoT sensor node has limited studies, especially in battery life. Therefore, this study aims to implement and analyze an efficient data collection algorithm for IoT-based smart metering applications in consideration with energy consumption. The system items used are Arduino Uno, Wi-Fi-ESP8266, and water flow sensors. The applied algorithm is an efficient data collection algorithm for water meter (EDCDWM) to reduce the number of packet transmissions. Arduino performed this system's implementation, while the simulation and analysis performed by MATLAB R2019b. The average percentage of energy saved by the applied algorithms of EDCDWM absolute change; and EDCDWM with relative differences in all nodes are around 60% and 93%, respectively

    Corporate reporting and disclosures in the emerging capital market of Kuwait:the perceptions of users and preparers

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    The objective of this paper is to investigate the perceptions of users and preparers regarding financial disclosure practices in annual reports of Kuwaiti listed firms. To measure participants' views, a questionnaire survey was distributed in Kuwait between October and December 2012, to preparers (financial managers) and users (financial analysts) within Kuwaiti listed companies. The study compares between the perceptions of financial managers and financial analysts regarding disclosing information in corporate annual reports as well as the main obstacles facing the disclosure process and what the problems restricting the use of companies' annual reports. The study also seeks to investigate whether there is a perceived need for improving the usefulness of Kuwaiti companies' annual reports for decision-making. The results, based on 137 responses, indicate that accounting practices in Kuwaiti firms are firmly rooted in a decision-usefulness tradition with management and the board of directors viewed as the key audience for reporting information. Indeed, the annual reports of Kuwaiti listed companies are perceived as the most important sources of information. On the whole both users and preparers shared similar concerns regarding the volume of information contained within annual reports; however, their views differed in terms of identifying potential solutions. The results of the study are likely to have implications for decision makers, the academic community and accounting standard setters. 2018 Macmillan Publishers Ltd., part of Springer Nature

    Enhanced Transduction and Replication of RGD-Fiber Modified Adenovirus in Primary T Cells

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    Background: Adenoviruses are often used as vehicles to mediate gene delivery for therapeutic purposes, but their research scope in hematological cells remains limited due to a narrow choice of host cells that express the adenoviral receptor (CAR). T cells, which are attractive targets for gene therapy of numerous diseases, remain resistant to adenoviral infection because of the absence of CAR expression. Here, we demonstrate that this resistance can be overcome when murine or human T cells are transduced with an adenovirus incorporating the RGD-fiber modification (Ad-RGD). Methodology/Principal Finding: A luciferase-expressing replication-deficient Ad-RGD infected 3-fold higher number of activated primary T cells than an adenovirus lacking the RGD-fiber modification in vitro. Infection with replicationcompetent Ad-RGD virus also caused increased cell cycling, higher E1A copy number and enriched hexon antigen expression in both human and murine T cells. Transduction with oncolytic Ad-RGD also resulted in higher titers of progeny virus and enhanced the killing of T cells. In vivo, 35–45 % of splenic T cells were transduced by Ad-RGD. Conclusions: Collectively, our results prove that a fiber modified Ad-RGD successfully transduces and replicates in primary

    Community pharmacists’ perspectives on cardiovascular disease pharmaceutical care in the United Arab Emirates: a questionnaire survey-based analysis

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    Background: Community pharmacists play an intermediary role between prescribing physicians and patients in the United Arab Emirates (UAE) and thus are responsible for ensuring that patients receive optimal cardiovascular disease (CVD) pharmaceutical care.Methods: we used a cross-sectional design to assess the perceptions and practices of community pharmacists concerning pharmaceutical care for patients with CVD. A trained researcher visited randomly selected community pharmacies and used a structured questionnaire to conduct in-person interviews with pharmacists. The questionnaire collected demographic data and information on perceptions and practices regarding CVD pharmaceutical care.Results: Five hundred and fifty-one participants were recruited. The average participant age (mean ± SD) was 35 ± 2.7 years. The average perception score regarding CVD prevention and management was 75.6% (95% confidence interval [CI] 77.1%–74.2%), and the average practice score for CVD prevention and management was 87.1% (95% CI 76.5%–79.6%). Bivariate analysis revealed that gender (p = 0.001), education level (p &lt; 0.001), pharmacy position (p = 0.004), work experience (p &lt; 0.001), number of patients served per day (p &lt; 0.001) and being trained on CVD prevention and management (p &lt; 0.001) were significantly associated with perceptions about the prevention and management of CVD. Better practice scores were seen among older participants (OR 1.01; 95% CI 1–1.019), postgraduates (OR 1.77; 95% CI 1.66–1.89), workers at chain pharmacies (OR 1.24; 95% CI 1.11–1.39), pharmacists in charge (OR 1.22; 95% CI 1.01–1.47), pharmacists with &gt;10 years of experience (OR 11.3; 95% CI 6.01–15.62), pharmacists with 6–10 years of experience (OR 4.42; 95% CI 3.90–5) and pharmacists trained on CVD prevention and management (OR 1.29; 95% CI 1.15–1.46).Conclusion: Pharmacy practitioners working in community pharmacies in the UAE actively engage in delivering pharmaceutical care to patients, playing a role in CVD management and prevention. However, they showed low levels of involvement in other healthcare services, specifically in screening and measuring patients’ weight, glucose levels, and blood pressure, monitoring treatment responses, maintaining medical records, and reviewing medication refill histories. Activities such as educating patients, providing medication counseling, offering support for treatment adherence, and fostering collaborative relationships with other healthcare providers should be encouraged among UAE community pharmacists to ensure the provision of high-quality patient care
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