Towards Efficient and Scalable Data-Intensive Content Delivery: State-of-the-Art, Issues and Challenges

This chapter presents the authors’ work for the Case Study entitled “Delivering Social Media with Scalability” within the framework of High-Performance Modelling and Simulation for Big Data Applications (cHiPSet) COST Action 1406. We identify some core research areas and give an outline of the publications we came up within the framework of the aforementioned action. The ease of user content generation within social media platforms, e.g. check-in information, multimedia data, etc., along with the proliferation of Global Positioning System (GPS)-enabled, always-connected capture devices lead to data streams of unprecedented amount and a radical change in information sharing. Social data streams raise a variety of practical challenges: derivation of real-time meaningful insights from effectively gathered social information, a paradigm shift for content distribution with the leverage of contextual data associated with user preferences, geographical characteristics and devices in general, etc. In this article we present the methodology we followed, the results of our work and the outline of a comprehensive survey, that depicts the state-of-the-art situation and organizes challenges concerning social media streams and the infrastructure of the data centers supporting the efficient access to data streams in terms of content distribution, data diffusion, data replication, energy efficiency and network infrastructure. The challenges of enabling better provisioning of social media data have been identified and they were based on the context of users accessing these resources. The existing literature has been systematized and the main research points and industrial efforts in the area were identified and analyzed. In our works, in the framework of the Action, we came up with potential solutions addressing the problems of the area and described how these fit in the general ecosystem

The relationship between physical factors (Wrist ratio) and electrophysiologic factors of median nerve in carpal tunnel syndrome in women

Carpal tunnel syndrome (CTS) is considered by researchers because of its high prevalence, and several studies have been done to find the causes and factors which increase the chance for the syndrome. These studies have shown relationships between this syndrome with some physical parameters like wrist dimensions, weight and systemic conditions. There is no investigation on risk factors in CTS in our country. So the main goal of this research is to find and introduce predisposing factors for carpal tunnel syndrome. Methods: Seventy patients and 33 controls 22 to 70 years old were studied. Standard methods for median and ulnar nerve studies were used and questionnaires included physical measurements, history of diseases and personal information were completed for each person. Results: Patients had higher wrist ratio (mean difference, 0.0267, P<0.001), weight (mean difference: 6.098, P<0.001) and body mass index (mean difference: 3.376, P<0.001). Regression analysis showed strong positive relation between wrist ratio and median latencies. The strongest correlation was found between wrist ratio and median minus ulnar distal sensory latencies (Y2=0.4014, P<0.0001). No relation was found between weight and body mass index with median latencies. Seventy-nine percent of patients and 48.5% of controls had wrist ratio of 0.7 or greater (P<0.05). Seventy-two percent of patients with repetetive hand activities and 78% with associated conditions had wrist ratio of 0.7 or greater. Seventy-six percent had wrist ratio less than 0.7. No relationship was found between obesity, diabetes, thyroid disorders, rheumatoid arthritis, taking oral contraceptive, hysterectomy, oophorectomy, menopause and repetetive hand activities with involvement of carpal tunnel syndrome. Discussion: Wrist dimensions seem to be an important predictor for carpal tunnel syndrome also in patients with associated conditions. If individuals with squarer wrists are involved in special conditions, they may show symptoms of the syndrom. Carpal tunnel syndrome is caused by many factors but wrist dimensions seem to be a predisposing factor and provides an explanation for bilateral involvement or familial occurrence of it

The estimation of survival function for colon cancer data in Tehran using non-parametric Bayesian model

Background: Colon cancer is the third cause of cancer deaths. Although colon cancer survival time has increased in recent years, the mortality rate is still high. The Cox model is the most common regression model often used in medical research in survival analysis, but most of the time the effect of at least one of the independent factors changes over time, so the model cannot be used. In the current study, the survival function for colon cancer patients in Tehran is estimated using non-parametric Bayesian model. Methods: In this survival study, 580 patients with colon cancer who were recorded in the Cancer Research Center of Shahid Beheshti University of Medical Sciences since April 2005 to November 2006 were studied and followed up for a period of 5 years. Survival function was plotted with nonparametric Bayesian model and was compared with the Kaplan-Meier curve. Results: Of the total of 580 patients, 69.9 of patients were alive. 45.9 of patients were male and the mean age of cancer diagnosis was 65.12 (SD= 12.26) and 87.7 of the patients underwent surgery. There was a significant relationship between age at diagnosis and sex and the survival time while there was a non-significant relationship between the type of treatment and the survival time. The survival functions corresponding to the two treatment groups cross, in comparison with the patients who had no surgery in the first 30 months, showed a higher level of risk in the patients who underwent a surgery. After that, the survival probability for the patients undergoing a surgery has increased. Conclusion: The study showed that survival rate has been higher in women and in the patients who were below 60 years at the time of diagnosis

Trends of quality of life changes in amyotrophic lateral sclerosis patients

Background Amyotrophic lateral sclerosis (ALS) is an incurable progressive neurodegenerative disease and thus the assessment of quality of life (QOL) changes and factors that may influence its course is valuable in the meantime. Objectives The present study aimed to assess the deterioration rate of QOL and influencing factors in different subgroups of Iranian ALS patients. Methods 132 patients were evaluated in this prospective multicenter observational study. QOL was measured using ALS Assessment Questionnaire (ALSAQ-40) during 1 year follow up and its progression rate was assessed in different subgroups of patients according to age, sex, stage of disease, riluzole consumption, onset type. Also physical disability and functional disability were measured using MMT and ALSFRS-R scores respectively and their progression rates were compared with ALSAQ-40 changes. Results Significant deterioration of the scores of ALSAQ-40 during study was consistent in all of its domains (p = 0.000). There was a significant negative correlation between ALSFRS-R and MMT changes and ALSAQ-40 change (p = 0.000) and this was consistently observed in all domains of ALSAQ-40 (p = 0.00). ALSAQ-40 deterioration rate was shown to be significantly lower in severe/terminal stages compared to mild/moderate stages (p = 0.00). Significantly higher deterioration rate was observed in bulbar onset versus limb onset patients F (1,130) = 4.52, p = 0.04 but no significant difference was observed among other subgroups according to age, sex and riluzole consumption. Conclusion All domains of QOL significantly deteriorate during ALS course and there is a significant correlation between their changes and progression of physical and functional disabilities. Rate of degradation of QOL may be different at different stages of the disease. QOL worsens independent of factors such as sex, age and consumption of riluzole; but onset type (bulbar versus limb) is an imperative factor in quality of life changes during the disease course. © 2016 Elsevier B.V

On the effects of adding syngas to an ammonia-MILD combustion regime—A computational study of the reaction zone structure

This study examines the reaction zone structure of syngas/NH3/CH4 blends in moderate or intense low oxygen dilution (MILD) conditions to determine the effects of variations in NH3 and syngas mole fractions upon the stability of the reacting system and NOx emission. A series of axisymmetric turbulent combustion simulations are performed using OpenFOAM and selected reaction mechanisms and, a modified version of the eddy dissipation concept. An increasing amount of syngas is added to the reacting mixtures of NH3/CH4 in MILD conditions. It is observed that a reduction in the NH3 mole fraction increases the OH radical concentration, which implies a reduction in the ignition delay. Further, for a given NH3 mole fraction, an increase in the syngas content of the fuel blend along with a reduction in CH4 leads to a rise in the process maximum temperature near the entrance zone. This reduces the flow temperature gradient, decreases the CH2O mass fraction, and boosts the stability of MILD combustion. Additionally, adding syngas to ammonia for MILD combustion decreases the reaction zone weakening, which is a major problem in MILD combustion of ammonia. In particular, blending syngas with NH3 and reducing the amount of CH4 in the fuel blend increases flame speed and heat generation. When syngas is added to ammonia MILD combustion, NOx and NxO decrease, and more complete combustion is achieved

Geometrical inlet effects on the behavior of a non-premixed fully turbulent syngas combustion; a numerical study

This study numerically evaluates a three-dimensional, turbulent, non-premixed syngas (a mixture of H2 and CO) flame issued from a round nozzle. The flow Reynolds number on the basis of the inlet velocity and the nozzle diameter is 16,700 and the flame is shrouded by a coflow under atmospheric conditions. A computational tool with a modified k-omega turbulence model and eddy dissipation model is used for simulating the reacting flow and its immediate surroundings. The outcomes are first compared against the existing experimental data. This reveals that when β*, as a constant coefficient in the k-omega turbulence model, is 0.073, the numerical results match the experimental data with high accuracy. Subsequently, the effects of variations in the diameter of the inlet nozzle and its geometry are investigated. This shows that an increase in the inlet nozzle diameter leads to the downstream movement of the high-temperature region diminishing combustion efficiency. Importantly, it is shown that using the elliptical inlet nozzle with the large diameter of 1.2 based nozzle diameter (4.48 mm) assists the combustion performance and increases the maximum combustion temperature by up to 9.6%. It also results in a considerable reduction of the unburned fuels and enhances the flow residence time significantly

Amyotrophic lateral sclerosis progression: Iran-ALS clinical registry, a multicentre study

This study was designed to evaluate ALS progression among different subgroups of Iranian patients. Three hundred and fifty-eight patients from centres around the country were registered and their progression rate was evaluated using several scores including Manual Muscle Test scoring (MMT) and the revised ALS Functional Rating Scale (ALSFRS-R). Progression rate was analysed separately in subgroups regarding gender, onset site, stage of disease and riluzole consumption. A significant difference in MMT deterioration rate (p = 0.01) was noted between those who used riluzole and those who did not. No significant difference was observed in progression rates between male/female and bulbar-onset/limb-onset groups using riluzole. In conclusion, riluzole has a significant effect on muscle force deterioration rate but not functional scale. Progression rate was not influenced by site of onset or gender