613 research outputs found
Factors Affecting Hemodialysis Patients' Satisfaction with Their Dialysis Therapy
Aim. To assess the degree of satisfaction among hemodialysis patients and the factors influencing this satisfaction. Methods. Patients were recruited from 3 Saudi dialysis centers. Demographic data was collected. Using 1 to 10 Likert scale, the patients were asked to rate the overall satisfaction with, and the overall impact of, their dialysis therapy on their lives and to rate the effect of the dialysis therapy on 15 qualities of life domains.
Results. 322 patients were recruited (72.6% of the total eligible patients). The mean age was 51.7 years (±15.4); 58% have been on dialysis for >3 years. The mean Charlson Comorbidity Index was 3.2 (±2), and Kt/V was 1.3 (±0.44). The mean satisfaction score was (7.41 ± 2.75) and the mean score of the impact of the dialysis on the patients' lives was 5.32 ± 2.55.
Male patients reported worse effect of dialysis on family life, social life, energy, and appetite. Longer period since the commencement of dialysis was associated with adverse effect on finances and energy. Lower level of education was associated with worse dialysis effect on stress, overall health, sexual life, hobbies, and exercise ability. Conclusion. The level of satisfaction is affected by gender, duration on dialysis, educational level, and standard of care given
Intrusion Detection Framework for Industrial Internet of Things Using Software Defined Network
The Industrial Internet of Things (IIoT) refers to the employment of the Internet of Things in industrial management, where a substantial number of machines and devices are linked and synchronized with the help of software programs and third platforms to improve the overall productivity. The acquisition of the industrial IoT provides benefits that range from automation and optimization to eliminating manual processes and improving overall efficiencies, but security remains to be forethought. The absence of reliable security mechanisms and the magnitude of security features are significant obstacles to enhancing IIoT security. Over the last few years, alarming attacks have been witnessed utilizing the vulnerabilities of the IIoT network devices. Moreover, the attackers can also sink deep into the network by using the relationships amidst the vulnerabilities. Such network security threats cause industries and businesses to suffer financial losses, reputational damage, and theft of important information. This paper proposes an SDN-based framework using machine learning techniques for intrusion detection in an industrial IoT environment. SDN is an approach that enables the network to be centrally and intelligently controlled through software applications. In our framework, the SDN controller employs a machine-learning algorithm to monitor the behavior of industrial IoT devices and networks by analyzing traffic flow data and ultimately determining the flow rules for SDN switches. We use SVM and Decision Tree classification models to analyze our framework’s network intrusion and attack detection performance. The results indicate that the proposed framework can detect attacks in industrial IoT networks and devices with an accuracy of 99.7%
Effectiveness of Stimulating Neural Branching Strategies in Developing Creative and Critical Thinking among Eighth Grade Students in Sultanate of Oman
This research aims to examine the effect of teaching by using strategies that stimulate neural branching in creative and critical thinking of study groups. The sample of this study consisted of two experimental groups and a control group. In terms of the treatment, one experimental group was taught using strategies that stimulate the neural branching in human brain mentally. The other experimental group was taught using the same strategies supported by technology. The control group was taught using the traditional instruction. The sample included (95) male student and (102) female students from two schools of the governorate of Muscat. To answer the research questions, Torrance test of creative thinking (TTCT) and Watson & Glaser critical thinking test (WGCTT) were used. The results show that the experimental groups significantly outperformed the control group with respect to the creative thinking test. However there were no statistically significant differences between the study's groups in the critical thinking test. This study recommends investment of mental capacities of the learners to encourage creative thinking and train teachers on using methods that stimulate neural branching
Transparent conductive oxide films for high-performance dye-sensitized solar cells
In this paper, atmospheric pressure chemical vapor deposition of fluorine-doped tin oxide (FTO) thin films of various thicknesses and dopant levels is reported. The deposited coatings are used to fabricate dye-sensitized solar cells, which exhibited reproducible power conversion efficiencies in excess of 10%. No surface texturing of FTOs or any additional treatment of dye-covered films is applied. In comparison, the use of commercial FTOs showed a lower cell efficiency of 7.11%. Detailed analysis showed that the cell efficiencies do not simply depend on the resistivity of FTOs but instead rely on a combination of carrier concentration, thickness, and surface roughness properties
Evaluation of performance-based earthquake engineering in Yemen
Building codes follow a common concept in designing buildings to achieve an acceptable seismic performance. The objective underlying the concept is to ensure that the buildings should be able to resist minor earthquake without damage, resist moderate earthquake with some non-structural damage, and resist major earthquakes without collapse, but some structural as well as non-structural damage. This study aims to evaluate the performance-based seismic to come up with necessary recommendations for both future practices, essential review, and restoration of existing structures in Yemen. To do this real case studies incorporated, and nonlinear pushover analysis is carried out. The analysis results presented and then assessed to find out the conformity with the required performance. The structural sections assumed at the beginning of the design, then the design repeated many times to achieve the selected performance criteria (the plastic hinge properties and the maximum displacement)
GT2004-53828 Instrumentation Selection and Uncertainty Analysis for Performance Test of Small Centrifugal Compressors
ABSTRACT In the design phase of centrifugal compressors, it is essential to have some experimental results on performance. The extent of usefulness of the experiments depends on quality and accuracy of the results. Part of proper experimental procedure is the correct selection of instrumentation leading to lower uncertainty in the final results. ASME PTC 10 (Performance Test Code on Compressors and Exhausters) requires fluctuation limits on the measured performance parameters. This does not guarantee limits for accuracy of performance parameters. Also, different experimental setup will affect uncertainty of the results, even with similar instrumentation accuracy. The present research deals with uncertainty analysis for performance evaluation of small-scale centrifugal compressor. The instrumentation errors are accommodated in the relation to ASME PTC 19.1 (test uncertainty). The analysis takes into consideration the correlated bias limits. Selection of proper type of instruments for measuring associated parameters is based on literature review. A case study is included as an example to illustrate the selection on instrumentation accuracy and preferred bias correlations. The analysis is a useful tool in designing experiments for testing compressor and optimizing accuracy of results
The Effect of surface topographical changes of two different surface treatments rotary instrument
One of the major innovations in endodontics has been the introduction of nickel-titanium (NiTi) alloy. This study evaluated the surface topographical changes of two different surface treatments rotary instrument after instrumentation and sterilization. 240 Extracted teeth were included in this study. 90 new AlphaKite and Revo-S NiTi rotary instruments were selected and divided into two groups (Group A 45 AlphaKite and group B 45 Revo-S). Each group were divided into three subgroups: (A1, B1) n=5 files were used as a control, (A2,B2) n=20 files were used to prepare three root canals using endodontic rotary motor then sterilized by autoclave for one cycle under 121°C at 15 psi for 30 minutes and (A3,B3) n=20 files were used to prepare nine root canals using the same rotary system then sterilized by autoclave for three cycles under 121°C at 15 psi for 30 minutes. Files were examined under scanning electron microscopy. On examining the AlphaKite, A1 revealed gross machining grooves on their surface with no pits, A2 showed disruption of cutting and A3 showed microcracks and deepening of the machining grooves. B1 showed a smoother surface with few machining grooves, B2 showed dulling and blunting of the cutting edges was predominant and B3 files showed plastic deformation in the form of unwinding of the flutes. The defects were less distributed along the electropolished Revo-S files than the physical vapor deposition AlphaKite
Antibacterial Activity of Small Molecules Which Eradicate Methicillin-Resistant Staphylococcus aureus Persisters
The serious challenge posed by multidrug-resistant bacterial infections with concomitant treatment failure and high mortality rates presents an urgent threat to the global health. We herein report the discovery of a new class of potent antimicrobial compounds that are highly effective against Gram-positive bacteria, including methicillin-resistant Staphylococcus aureus (MRSA). The compounds were efficiently synthesized in one-pot employing a cascade of Groebke-Blackburn-Bienayme and aza-Michael addition reactions. Phenotypic screening of the pilot library against various bacterial species including methicillin-sensitive and MRSA strains, has identified potent chemotypes with minimal inhibitory concentrations (MIC) of 3.125-6.25 mu g/ml. The most potent compounds were fast-acting at eradicating exponentially growing MRSA, with killing achieved after 30 min of exposure to the compounds. They were also able to kill MRSA persister cells which are tolerant to most available medications. Microscopic analysis using fluorescence microscope and atomic force microscope indicate that these compounds lead to disruption of bacterial cell envelopes. Most notably, bacterial resistance toward these compounds was not observed after 20 serial passages in stark contrast to the significant resistance developed rapidly upon exposure to a clinically relevant antibiotic. Furthermore, the compounds did not induce significant hemolysis to human red blood cells. In vivo safety studies revealed a high safety profile of these motifs. These small molecules hold a promise for further studies and development as new antibacterial agents against MRSA infections.This work was supported by the generous grants from the
IsDB-Transformers Fund and the Research Funding Department,
University of Sharjah, UAE (CoV19-0306)
Thermal shock resistance of yttrium aluminium oxide Y3Al5O12 thermal barrier coating for titanium alloy
The high strength-to- weight ratio of titanium alloys allows their use in jet engines. However, their use is restricted by susceptibility to oxidation at high temperatures. In this study, the possibility of increasing the operating temperature of titanium alloys through using Yttrium Aluminum Oxide (YAG) as a thermal barrier coating material for Ti-6Al-4V substrate is studied. The study concludes that YAG can be utilized to increase the operating temperature of Ti-6Al-4V titanium alloy from around 350 °C to 800 °C due to its low thermal conductivity and phase stability up to its melting point. In addition, its lower oxygen diffusivity in comparison with the standard YSZ material will provide a better protection of the titanium substrate from oxidation. In this work, coating was created using atmospheric plasma spray. X-ray Diffraction (XRD) and Scanning Electron Microscope (SEM) were used to examine coatings' composition and structure. The coating was characterized by thermal shock test, Vickers hardness test and adhesion strength test. X-ray diffraction indicated that the coating was of a partially crystalline Y3Al5O12 composition. The coating was porous with excellent thermal shock resistance at 800 oC, with a Vickers micro-hardness of 331.35 HV and adhesion strength of 17.6 MPa
Distribution of heavy metals around the Barakah nuclear power plant in the United Arab Emirates
© 2017, Springer-Verlag Berlin Heidelberg. Inductively coupled plasma emission spectroscopy was used to measure the concentrations of heavy metals in 58 samples collected from the Barakah nuclear power plant (BNPP) area, UAE. The grain size distribution was symmetric, but the samples ranged from fine to coarse sand. The inverse relationship between grain size and heavy metal contaminations was validated. The pre-operational average heavy metal contaminations around the BNPP were 0.03, 0.40, 1.2, 2.05, 1.66, 1.6, 5.9, 7.3, 7, 8.8, 60, and 2521 ppm for Cd, Mo, Co, Cu, Pb, As, Zn, Ni, V, Cr, Mn, and Fe, respectively. The spatial distribution was more compact in the south compared to the north, with less severe contaminations in the east and west. The negative geoaccumulation indices suggest an uncontaminated area, and the BNPP has minor enrichments. All concentrations were significantly below the safe limits set by the Dutch guidelines. The levels of heavy metals reported in the UAE were lower than levels reported in countries around the world
- …