217 research outputs found
Shortest Paths Routing Problem in MANETs
The need for communication services is rapidly increasing, because the mobile communication service is synonymous with an ideal communication style realizing communication anytime, anywhere and with anyone. The availability of a path depends on the number of links and the reliability of each link forming the path. Many routing metrics in terms of number of links have been proposed, such as the shortest path routing. Shortest path routing selects a path having minimum cost to forward the data to the destination node. Shortest path routing algorithm selection depends on direct traffic form source to destination, maximizing the network performance and minimizing the cost. Performance of the network can be enhanced through shortest path routing but it also depends upon the functionality of the routing protocol and the parameters that are selected for the shortest path routing. The primary goal of such an adhoc network routing protocol is correct and efficient route establishment between a pair of nodes so that messages may be delivered in a timely manner. Route construction should be done with a minimum of cost, overhead and bandwidth consumption. Some of researchers explored the concept of shortest path routing over ad hoc network. Each one uses his own parameters with different topology. No one uses all parameters. In this paper, we will discuss the solutions ideas that have been proposed by them
Evaluation of Python Error Message Interpretation: Study on Students with Different Levels of Programming Experience
Error messages are a helpful tool for everyone interested in learning a programming language. Even after learning the language, novice and experienced programmers alike, have to interact with an error message one way or another. However, there is no single programming language that is usedacross all platforms and systems, so the programmers have to write programs in many different languages. If the programming languages have similar structures, working with a new language is relatively easy. We have asked the question, whether the same effect could be observed in case of error messages. We designed an online survey which was conducted internationally to measure whether the general experience of programmers from any programming language influences the programmer’s ability to correct python error message. The survey was aimed at students who have some experience with programming. We find in comparison with novices, on average the experiencedprogrammers find and fix an error in the code given the sameerror message with its corresponding code snippet. Additionally,we see correlations between the average of correctly fixed errorsand number of programming languages that the participants hadexperience with, as well as their chosen major and their age
Task Scheduling Optimization in Cloud Computing by Jaya Algorithm
Cloud computing provides resources to its consumers as a service. The cloud computing paradigm offers dynamic services by providing virtualized resources via the internet for enabling applications, and these services are provided by large-scale data centers known as clouds. Cloud computing is entirely reliant on the internet to provide its services to consumers. Cloud computing offers several advantages, including the fact that users only pay for what they use weekly, monthly, or yearly, that anybody with an internet connection may use the cloud, and that there is no need to purchase resources, hardware, or software on their own. This paper proposes an efficient task scheduling algorithm based on the Jaya algorithm for the cloud computing environment. We evaluate the performance of our method by applying it to three instances. The recommended technique produced the optimal solution in makespan, speedup, efficiency, and throughput, according to the findings
Predictors of Long-term Disability in Multiple Sclerosis: Real World Data from a Cohort of Egyptian Patients
Background: Specification of prognostic factors in multiple sclerosis (MS) is crucial for clinicians to guide therapeutic protocols. This study aimed to identify demographic, clinical, and radiological factors associated with disability on a long-term basis in relapsing-remitting MS (RRMS) and secondary progressive MS (SPMS).Methods: This was a retrospective study conducted on patients with RRMS and SPMS with a disease duration of at least 10 years. Demographic, clinical, and radiological parameters were collected from the medical records.Results: During the study period, 217 patients were recruited with a mean disease duration of 14.9 ± 4.6 (range: 10-35) years. Regression analysis revealed that age (B = 0.071, CI: 0.00-0.132, P = 0.025), male sex (B = –0.825, CI: –1.444 to –0.206, P = 0.009), duration between first 2 attacks (B = -0.007, CI: -0.015-0.000, P = 0.037), and involvement of pyramidal (B = 0.754, CI: 0.051-1.457, P = 0.036) or cerebellar domains (B = 1.355, CI: 0.542-2.168, P = 0.001) at disease onset were the only parameters that had an independent effect on EDSS.Conclusion: Predictors of long-term disability in our cohort were closely similar, but not typically identical to predictors reported in the literature. Age, male sex, short duration between first 2 relapses pyramidal and cerebellar affection were the strongest predictors of disability in patients with RRMS and SPMS
An Efficient Firefly Algorithm for Optimizing Task Scheduling in Cloud Computing Systems
As user service demands change constantly, task scheduling becomes an extremely significant study area within the cloud environment. The goal of scheduling is distributing the tasks on available processors in order to achieve the shortest possible makespan while adhering to priority constraints. In heterogeneous cloud computing resources, task scheduling has a large influence on system performances. The various processes in the heuristic-based algorithm of scheduling will result in varied makespans when heterogeneous resources are utilized. As a result, a smart method of scheduling must be capable of establishing precedence efficacy for each task to decrease makespan time. In our study, we develop a novel efficient method of scheduling tasks according to the firefly algorithm to tackle an essential task and schedule a heterogeneous cloud computing problem. We evaluate the performance of our algorithm by putting it through three situations with changing amounts of processors and numbers of tasks. The findings of the experiment reveal that our suggested technique found optimal solutions substantially more frequently in terms of makespan time when compared with other methods
Development and validation of different spectrophotometric and chromatographic methods for determination of clotrimazole and hydrocortisone in a topical cream
In this study, we developed and validated different spectrophotometric and chromatographic methods for determination of clotrimazole (CLO) and hydrocortisone (HDC) in their combined dosage form. The developed spectrophotometric methods were first derivative spectrophotometry (1D) by measuring the peak amplitude at 247.4 and 236.2 nm for CLO and HDC, respectively, second derivative of ratio spectra (2DD) at 225.4 nm for CLO and 269 nm for HDC, dual wavelength spectrophotometry (DW) by measuring absorbance difference between 225.4 and 264 nm for CLO and between 228 and 247 nm for HDC determination, advanced absorbance subtraction method (AAS) between 225.4 and 264 nm and mean centering of ratio spectra (MCR) spectrophotometric method in the range of 232-265 nm. On the other hand, the proposed chromatographic method was Ultra Performance Liquid Chromatography method (UPLC) using acetonitrile:water (50:50, v:v) as a mobile phase and the peaks were detected at 228 nm. All these methods were successfully applied to determine the two studied drugs in pure forms; laboratory prepared mixtures and combined dosage form. Methods validations were carried out regarding linearity, accuracy, precision and selectivity. The spectrophotometric methods exhibited a linear dynamic range over 5-40 and 5-45 µg/mL for CLO and HDC, respectively, and over 3-35 and 5-50 µg/mL for UPLC method. Sensitive and selective spectrophotometric and UPLC methods for the determination of clotrimazole and hydrocortisone in their topical formulation were successfully developed and validated. The developed methods were statistically confirmed to be accurate, precise and reproducible
Curative role of lactulose, L-carnitine, alpha-lipoic acid and combination of L-carnitine and alpha-lipoic acid in a rat model of acute hepatic encephalopathy: Biochemical observations
Purpose: To determine whether a combination L-carnitine and α-lipoic acid (ALA) can alleviate the toxic effects of thioacetamide (TAA) via their potent antioxidant and free radical-scavenging activities.Methods: Rats were injected with TAA for 3 days to induce acute hepatic failure. TAA induced rats were treated with each of lactulose, L-carnitine and ALA alone and a combination of L-carnitine and ALA for 3 months. Thereafter, biochemical indices, ammonia levels, oxidative stress markers, and the levels of inflammatory markers were assessed in serum, liver and brain.Results: A significant improvement was observed after 3 months of antioxidants treatment. Lactulose, L-carnitine and ALA significantly decreased serum concentrations of alanine transaminase (ALT), aspartate aminotransaminase (AST) and level of total bilirubin while both levels of total protein (TP) and albumin (ALB) were significantly increased (p < 0.05 ) compared to TAA group. In addition, each of antioxidants alone significantly decreased ammonia (NH3) concentrations of serum, liver and brain in TAA-induced rats. Treatment with antioxidants for 3 months significantly (p < 0.05) decreased Malondialdehyde (MDA) and nitric oxide (NO) while antioxidant enzyme activities of glutathione peroxidase (GPX) and superoxide dismutase (SOD) were significantly increased (p < 0.05) in liver and brain tissues. The expressions of serum tumor necrosis factor-α (TNF-α) and soluble protein (S100-β) were significantly (p < 0.05) down-regulated in TAA-induced rats.Conclusion: L-carnitine in combination with ALA can mitigate HE induced experimentally in rats. The protective efficacy of L-carnitine in combination with ALA in HE can be attributed to suppression of oxidative stress, ammonia concentration and the levels of inflammatory markers. Thus, it may have the potential to be used to treat liver cirrhosis in clinical settings.Keywords: Lactulose, L-carnitine, α-Lipoic acid, Hepatic encephalopathy, Thioacetamide, Oxidative stress, Cirrhosis, Acute liver injur
Assessment of Quality of Life among Beta-Thalassemia Major Patients Attending the Hematology Outpatient Clinics at Cairo University Hospital
AIM: This paper aimed at assessing the quality of life (QoL) among beta (β)-thalassemia major patients using the short-form-36questionnaire (SF-36) and determining the factors associated with it.
METHODS: A cross-sectional study was conducted among β-thalassemia major patients who were attending the hematology outpatient clinic at Cairo University Hospital using the consecutive sampling technique. Data were collected between October 2016 and March 2017. The QoL was assessed for patients aged ≥17 years. During the study period, a total number of 112 patients were included for participation.
RESULTS: The mean age of the studied group was 18.32 ± 1.33 years. Most of the included patients (93.63%) had 1 monthly blood transfusion. The mean total score of SF-36 was 44.90 ± 7.54. Among the QoL domains of the studied patients, the “general health perception” domain was the most affected one with a mean score of (add the value of the score here), while the “vitality” domain was the least affected one. No statistically significant difference was reported between males and females regarding different QoL domains except for the “vitality” domain which mean score was significantly higher in males compared to females (p = 0.05). The age at onset of the disease and at first blood transfusion was the most documented factors to be positively correlated with the QoL among the studied patients.
CONCLUSION: This study revealed that the QoL in thalassemia major patients is compromised. QoL assessment should be performed for all thalassemia patients to determine and implement the necessary interventions that focus on the affected domains
Methylene tetrahydrofolate reductase, transforming growth factor-β1 and lymphotoxin-α genes polymorphisms and susceptibility to rheumatoid arthritis
AbstractBackgroundRheumatoid arthritis is a widely prevalent autoimmune disorder with suggested genetic predisposition.ObjectivesThe aim of this study is to detect the pattern of genetic polymorphism of methylene tetrahydrofolate reductase (MTHFR C677 T and A1298 C), transforming growth factor-β1 (TGF-β1 T869 C) and lymphotoxin-α (LT-α A252G) in patients having rheumatoid arthritis and correlate these patterns to disease activity and serum levels of tumor necrosis factor-alpha (TNF-α), B-Cell Activating Factor (BAFF), and osteopontin.MethodsA total of 194 subjects, 90 controls and 104 patients with rheumatoid arthritis were genotyped for MTHFR C677 T and A1298 C, TGF-β1 T869 C and LT-α A252G polymorphisms using a methodology based on PCR-RFLP. Also serum levels of TNF-α, osteopontin and BAFF were measured by ELISA kits.ResultsThe CT genotype and T allele of MTHFR C677 T and GG genotype and G allele of LT-α A252G are associated with the risk of RA and with higher levels of the pro-inflammatory cytokine, TNF-α in patients with rheumatoid arthritis.ConclusionOur findings suggest that there is association between MTHFR C677 T and LT-α A252G genes polymorphisms and increased risk of RA in this sample of Egyptian population
- …