252 research outputs found
CIFAR-10: KNN-based Ensemble of Classifiers
In this paper, we study the performance of different classifiers on the
CIFAR-10 dataset, and build an ensemble of classifiers to reach a better
performance. We show that, on CIFAR-10, K-Nearest Neighbors (KNN) and
Convolutional Neural Network (CNN), on some classes, are mutually exclusive,
thus yield in higher accuracy when combined. We reduce KNN overfitting using
Principal Component Analysis (PCA), and ensemble it with a CNN to increase its
accuracy. Our approach improves our best CNN model from 93.33% to 94.03%
A model for examining the relation between news media literacy skills, heuristic-systematic news processing and political knowledge levels
The study aimed to test the relation between the levels of news media literacy skills, types of news processing levels, and the levels of political knowledge. Also, the study investigated the relation between news media reliance, media gratification sought and elaborative processing, and levels of political knowledge. A survey method was used among undergraduate and graduate students at the American University in Cairo. Furthermore, this research developed a scale for measuring news media literacy skills among university students. The scales\u27 items tested on a sub sample then statistically examined through factor analysis for refining the final items of the final survey. Moreover, this research contributed to the field through proposing a new scale for assessing news media literacy skills (SNMLS) that has been derived from previous scales, with adaptation to Egyptian context and the proposed conceptual framework. The scale achieved high internal reliability
Formation Damage Due To Iron Precpitation In Limestone, Dolomite and Sandstone Cores
Formation damage due to iron precipitation continues to be a major problem in the oil field. Research has established that as the pH of injected acid increases, iron (III) ions start to precipitate and block the pores in the formation, significantly reducing production. However, where exactly this iron precipitates and how iron precipitation changes with different lithologies has not yet been comprehensively studied.
Coreflood experiments were conducted on carobonate (calcite and dolomite) and sandstone cores to assess the effects of temperature and iron concentrations on the degree of damage caused by iron precipitation during an acid job. The temperature values tested were 200 and 300°F. Iron concentrations ranging from 5,000 to 10,000 ppm were used. The core effluent samples were analyzed by ICP (Inductively Coupled Plasma) to measure the concentrations of key cations.
Coreflood experiments, revealed that iron precipitates across the entire core. Iron precipitation was severely detrimental in sandstone cores compared to those composed of calcite and dolomite. While limestone cores showed the least formation damage from iron precipitation, coreflood tests indicated that as the iron concentration increases, the damage was more evident. On the other hand, increasing the temperature adversely affected sandstone and dolomite cores, but improved the final permeability of limestone cores.
In this study, the location of the iron precipitation is determined for three different lithologies. The effects of different parameters are studied to determine the best conditions that would lead to a decrease in iron precipitation and hence prevent formation damage. Iron control agents are not always needed, as previously thought
Consistent Coupled Optical and Thermal Analysis of Volumetric Solar Receivers with Honeycomb Absorbers
International audienceIn concentrating solar power plants with central towers, successful design of volumetric solar receivers requires proper understanding of the interaction between optical, heat transfer, and fluid flow phenomena occurring at the microscopic scale of receiver structure material and their effect on the overall solar to thermal efficiency. In the present article, coupled, 3D, optical, heat transfer and fluid flow numerical models have been developed for the analysis and design of honeycomb volumetric receiver modules. The optical model considers the absorptivity and micro dimensions of honeycomb absorber structure and employs a Monte Carlo ray tracing technique to calculate and analyze the absorbed solar heat flux distribution. This, in turn, is employed as a volumetric heat source term at the solid surface for consistent heat transfer and fluid flow modeling using a realistic solution domain and proper boundary conditions. The validated models have been employed to investigate the effects of different types of absorber materials, material absorptivity, and air flow rate on the performance of the solar receiver. It has been shown that positive volumetric effect and high solar-to-thermal efficiency can be obtained by controlling the absorbed radiation heat flux distribution within the honeycomb receiver using surface coating of the absorber material
EFFICIENCY OF CURCUMIN AND CHITOSAN NANOPARTICLES AGAINST TOXICITY OF POTASSIUM DICHROMATE IN MALE MICE
Objective: The purpose of this work is to examine the protective effect of nanocurcumin and nanochitosan supplementation against potassium dichromate toxicity in male mice.
Methods: Male albino mice weighing 25-30 gm were divided into six groups; the first group received saline. Second and third groups were given oral dose of nanocurcumin and nanochitosan respectively for 5 d. Fourth group was injected subcutaneously with a single dose of potassium dichromate for 24 h. Group five and six were administrated nanocurcumin and nanochitosan, respectively prior to potassium dichromate. Animals were anesthetized by ether anesthesia then bone marrow was harvested for chromosomal examination and epididymal sperms were collected for sperm morphology, while Kidneys and testes were collected for western blot and biochemical analysis.
Results: Potassium dichromate induced significant (P≤0.05) increase in chromosome and sperm abnormalities as well as testicular and renal MDA, renal MPO, renal contents of IL-18 and IGF-1, testicular contents of caspase 3 and cytosolic cytochrome c, a reduction in testosterone level, and GPx of renal and testicular tissues compared to control group. Pretreatment with both types of nanoparticles showed significant (P≤0.05) mitigation against most alterations induced by potassium dichromate; moreover, nanochitosan gave more significant (P≤0.05) improvement against chromosome and sperm abnormalities than nanocurcumin.
Conclusion: The present study revealed that the selected nanoparticles have antioxidant as well as antigenotoxic properties against toxicity of potassium dichromate
THERAPEUTIC POTENCY OF SWEET ORANGE JUICE OVER LIVER GENOTOXICITY INDUCED BY PESTICIDE LANNATE IN RATS
Objective: The aim of the present investigation was to study the potential effect of sweet orange juice against liver genotoxicity induced by lannate.
Methods: adult 36 female rats were divided into 6 groups: group C (control group), group L (lannate group) injected intraperitoneal (i. p.) with 1 mg/kg b. wt. lannate for one day, group J (orange juice group) orally administered a dose of 0.1 ml/10 g b. wt. of orange juice for 48 h, group J+L received the orange juice prior to lannate, group J with L received lannate in continuous with the orange juice and group L+J received lannate prior to the orange juice. Tested parameters were DNA fragmentation, micronucleus, histopathology examination and biochemical analysis.
Results: it was found that, the intake of lannate caused high DNA fragmentation and significant increase (P<0.001) in the number of micronucleated polychromatic erythrocytes in the bone marrow. Furthermore, lannate exhibited some pathological changes in the liver tissues as well as a significant (P<0.001) decrease in the total antioxidative capacity (TAC) and a significant increase in the total oxidative capacity (TOC). On the other hand, orange juice administration of all treatments (pre-treatment, continuous and post-treatment) gave some amelioration against liver damage induced by lannate. While the best results were evidenced in the continuous treatment group where the juice could attenuate liver DNA fragmentation and significantly decreased (P<0.001) the number of micronucleated polychromatic erythrocytes. In addition, it improved the induced degenerative histopathological changes as well as ameliorated the changes occurred in TAC and TOC significantly (P<0.001).
Conclusion: the antigenotoxic impact of orange juice against lannate was therapeutic and hence can counteract the poisonous effect of the pesticide in people who exposed to it
A Survey on High Dimensional Computing with Arabic Language Processing
A growing amount of Arabic textual content comes accessible via the World Wide Web in properties and companies via Internet and Intranet services, there is a pressing need for technology and tools to handle the relevant data. In the context of Arabic processing of language, high-dimensional computation. The stemming method is intended to be used throughout document categorization to lower the high dimensionality of the domain of features, which improves categorization system performance, especially for highly modulating languages such as Arabic. It then digs into other sub-topics, such as methods for decreasing dimensionality, categorization computations, natural language processing jobs, and Arabic-specific applications. Each sub-topic is explored in depth, emphasising the main findings, techniques, and significant advances documented in the scientific literature. In addition, the survey report analyses future trends as well as prevalent obstacles in high-dimensional computing with Arabic language processing. It investigates the effectiveness and relevance of existing procedures while also exposing gaps and limits that need to be addressed further. The report provides knowledge of the present situation of the topic and suggests new directions for future studies by critically analysing the examined literature. This survey report is significant because of its ability to integrate and synthesise current knowledge, offering researchers as well as practitioners with a complete resource on the combination of high-dimensional computing with Arabic processing of languages. The paper may be utilised as an easy way to find pertinent works that cover a given issue for a particular dialect
End-of-life discontinuation of destination therapy with cardiac and ventilatory support medical devices: physician-assisted death or allowing the patient to die?
<p>Abstract</p> <p>Background</p> <p>Bioethics and law distinguish between the practices of "physician-assisted death" and "allowing the patient to die."</p> <p>Discussion</p> <p>Advances in biotechnology have allowed medical devices to be used as destination therapy that are designed for the permanent support of cardiac function and/or respiration after irreversible loss of these spontaneous vital functions. For permanent support of cardiac function, single ventricle or biventricular mechanical assist devices and total artificial hearts are implanted in the body. Mechanical ventilators extrinsic to the body are used for permanent support of respiration. Clinical studies have shown that destination therapy with ventricular assist devices improves patient survival compared to medical management, but at the cost of a substantial alteration in end-of-life trajectories. The moral and legal assessment of the appropriateness and permissibility of complying with a patient's request to electively discontinue destination therapy in a life-terminating act in non-futile situations has generated controversy. Some argue that complying with this request is ethically justified because patients have the right to request withdrawal of unwanted treatment and be allowed to die of preexisting disease. Other commentators reject the argument that acceding to an elective request for death by discontinuing destination therapy is 'allowing a patient to die' because of serious flaws in interpreting the intention, causation, and moral responsibility of the ensuing death.</p> <p>Summary</p> <p>Destination therapy with cardiac and/or ventilatory medical devices replaces native physiological functions and successfully treats a preexisting disease. We posit that discontinuing cardiac and/or ventilatory support at the request of a patient or surrogate can be viewed as allowing the patient to die if--and only if--concurrent lethal pathophysiological conditions are present that are unrelated to those functions already supported by medical devices in destination therapy. In all other cases, compliance with a patient's request constitutes physician-assisted death because of the pathophysiology induced by the turning off of these medical devices, as well as the intention, causation, and moral responsibility of the ensuing death. The distinction between allowing the patient to die and physician-assisted death is pivotal to the moral and legal status of elective requests for death by discontinuing destination cardiac and/or ventilatory medical devices in patients who are not imminently dying. This distinction also represents essential information that must be disclosed to patients and surrogates in advance of consent to this type of therapy.</p
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