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Search Results: 1 - 10 of 593307 matches for " J. M. Saken "
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The Young Solar Analogs Project: I. Spectroscopic and Photometric Methods and Multi-year Timescale Spectroscopic Results
R. O. Gray,J. M. Saken,C. J. Corbally,M. M. Briley,R. A. Lambert,V. A. Fuller,I. M. Newsome,M. F. Seeds,Y. Kahvaz
Physics , 2015,
Abstract: This is the first in a series of papers presenting methods and results from the Young Solar Analogs Project, which began in 2007. This project monitors both spectroscopically and photometrically a set of 31 young (300 - 1500 Myr) solar-type stars with the goal of gaining insight into the space environment of the Earth during the period when life first appeared. From our spectroscopic observations we derive the Mount Wilson $S$ chromospheric activity index ($S_{\rm MW}$), and describe the method we use to transform our instrumental indices to $S_{\rm MW}$ without the need for a color term. We introduce three photospheric indices based on strong absorption features in the blue-violet spectrum -- the G-band, the Ca I resonance line, and the Hydrogen-$\gamma$ line -- with the expectation that these indices might prove to be useful in detecting variations in the surface temperatures of active solar-type stars. We also describe our photometric program, and in particular our "Superstar technique" for differential photometry which, instead of relying on a handful of comparison stars, uses the photon flux in the entire star field in the CCD image to derive the program star magnitude. We present time series plots of our spectroscopic data for all four indices, and carry out extensive statistical tests on those time series demonstrating the reality of variations on timescales of years in all four indices. We also statistically test for and discover correlations and anti-correlations between the four indices. We discuss the physical basis of those correlations. As it turns out, the "photospheric" indices appear to be most strongly affected by continuum emission. We thus anticipate that these indices may prove to be useful proxies for monitoring continuum emission in the near ultraviolet.
Generating static perfect-fluid solutions of Einstein's equations
Hernando Quevedo,Saken Toktarbay
Physics , 2015, DOI: 10.1063/1.4921062
Abstract: We present a method for generating exact interior solutions of Einstein's equations in the case of static and axially symmetric perfect-fluid spacetimes. The method is based upon a transformation that involves the metric functions as well as the density and pressure of the seed solution. In the limiting vacuum case, it reduces to the Zipoy-Voorhees transformation that can be used to generate metrics with multipole moments. All the metric functions of the new solution can be calculated explicitly from the seed solution in a simple manner. The physical properties of the resulting new solutions are shown to be completely different from those of the seed solution.
The Problem of Using Competence-Based Approach and Information Technologies in Formation of Communicative Competence of the Future Specialists  [PDF]
Madina Murzakhanovna Akeshova, Kamalbek Meirbekovich Berkimbaev, Zhanali Erkinbekovich Daribaev, Gulmira Pernebekovna Meirbekova, Saken Koptleuovich Kurbaniyazov, Zagipa Kyrgyzbaevna Abdikulova
Creative Education (CE) , 2013, DOI: 10.4236/ce.2013.48073

As the result of educational modernization and joining the Republic of Kazakhstan to the Bologna process, A. Yasawi International Kazakh-Turkish University points out as one of its main problem the usage of competence-based approach and information technologies in highly qualified training of the future specialists of international level with professional activity, critical thinking and creativity because the competence-based approach and information technologies emphasize professional education and training of future specialists from practical and pragmatic aspects. Taking into consideration necessary elements of some approaches in pedagogical and psychological sciences such as systematic, personal-oriented and synergetic and others, the importance of competence-based approach as one of necessary base of formation of communicative competence and professional training of future specialists is pointed out. It has professional, pragmatic, humanistic, and practical features, which show its correlation and systematic advantages. Competence-based approach is one of the most effective means of developing methodological and creative thinking activity, professional and cultural norms of behavior, correction of oriented values on the base of educational system, changing activities based on principals of innovative approaches in teaching process of higher education. The results obtained by the use of competence-based approach and information technologies show improvements in formation of communicative competence of the future specialists. Correlation of competence-based approach and information technologies in teaching process show an increase, which points to a significant development and formation of communicative competence of the future specialists. The improvement is also represented in higher average grades of the experimental group and it shows the effectiveness of correlation of competence-based approach and information technologies in formation of communicative competence of the future specialists.

Development of Analytical Model for Modular Tank Vehicle Carrying Liquid Cargo  [PDF]
M. Toumi, M. Bouazara, M. J. Richard
World Journal of Mechanics (WJM) , 2013, DOI: 10.4236/wjm.2013.32010

The study of dynamics of tank vehicles carrying liquid fuel cargo is complex. The forces and moments due to liquid sloshing create serious problems related to the instability of tank vehicles. In this paper, a complete analytical model of a modular tank vehicle has been developed. The model included all the vehicle systems and subsystems. Simulation results obtained using this model was compared with those obtained using the popular TruckSim software. The comparison proved the validity of the assumptions used in the analytical model and showed a good correlation under single or double lane change and turning manoeuvers.

The Primary Radical of a Submodule  [PDF]
Lamis J. M. Abulebda
Advances in Pure Mathematics (APM) , 2012, DOI: 10.4236/apm.2012.25049
Abstract: In this paper we introduced a definition for the primary radical of a submodule with some of its basic properties. We also define the P-radical submodule and review some results about it. We find a method to characterize the primary radical of a finitely generated submodule of a free module.
On Co-Primarily Packed Modules  [PDF]
Lamis J. M. Abulebda
Advances in Pure Mathematics (APM) , 2015, DOI: 10.4236/apm.2015.54022

Let R be a commutative ring with 1, and M is a (left) R-module. We introduce the concept of coprimarily packed submodules as a proper submodule N of an R-module M which is said to be Coprimarily Packed Submodule. If \"\" where Na is a primary submodule of M for each \"\", then \"\" for some \"\". When there exists \"\" such that \"\"; N is called Strongly Coprimarily Packed submodule. In this paper, we list some basic properties of this concept. We end this paper by explaining the relations between p-compactly packed and coprimarily packed submodules, and also the relations

Understanding the Sociocultural Health Belief Model Influencing Health Behaviors among Saudi Stroke Survivors  [PDF]
Mohammed M. J. Alqahtani
Neuroscience & Medicine (NM) , 2015, DOI: 10.4236/nm.2015.64023
Abstract: Understanding patients’ beliefs of stroke, especially that cultural model which influences the medical management, is important. Professionals normally hold medical knowledge only about stroke, rather than the patients’ perceptions, which leads to limitations in cultural competency. Little is known about Saudi stroke survivors’ beliefs and behaviors related to their strokes. Methods: A qualitative methodology was used to collect in-depth information from stroke survivors. From March 2010 to October 2014, 45 stroke survivors were recruited from outpatient rehabilitation clinic at King Fahad Medical City (KFMC-RH), during their follow-up treatments. Results: Thematic content analysis yielded four major themes of the causes of stroke: medical, cultural, psychological and environmental. Three major themes were determined regarding stroke interventions: medical, lifestyle and behavioral, as well as cultural interventions. Stroke is most likely to be associated with a wide range of cultural beliefs by stroke survivors, leading them to cultural behaviors and management. All of these cultural interventions were typically used as an adjunct rather than an alternative to medical care. Conclusions: Health professionals need to be aware that cultural beliefs and their management are common problems for stroke survivors undergoing rehabilitation in a hospital. This study could be one step forward to help health professionals become culturally competent when working with stroke survivors in a rehabilitation setting in Saudi Arabia.
A Brief Parametric Analysis of Catastrophic or Disastrous Hurricanes That Have Hit the Florida Keys between 1900 and 2000  [PDF]
J. M. D’Andrea
American Journal of Computational Mathematics (AJCM) , 2018, DOI: 10.4236/ajcm.2018.81001
Abstract: The most intense and catastrophic hurricanes on record to hit the Florida Keys during 1900 to 1950 were in 1919, and 1935. From 1950 to 2000, the most intense hurricanes to hit or affect the Florida Keys were in 1960, 1965, and 1992. In this paper, we will present a brief parametric analysis of the hurricanes that have hit the Florida Keys in the last 100 years. This analysis will include the descriptive statistics, best fit probability distribution of the latitude of the catastrophic hurricanes and a confidence interval that detects the average latitude of hurricanes (category 3 or higher) which have hit the Florida Keys in the last 100 years.
Cytotoxicity Tests for Evaluating Medical Devices: An Alert for the Development of Biotechnology Health Products  [PDF]
M. N. P. Vidal, J. M. Granjeiro
Journal of Biomedical Science and Engineering (JBiSE) , 2017, DOI: 10.4236/jbise.2017.109033
Abstract: The risks and damages related to the use of products, technologies and services of sanitary interest can be due to defects or manufacturing failures. Certain products already contain a certain degree of risk, which requires strict quality control in their production, distribution and use, as well as in the disposal of their waste in the environment. With continuous development in science and technology, medical devices must undergo intradermal irritation and testing for sensitization, cytotoxicity, and acute systemic toxicity. In health care, biotechnology aims to provide technology-based products or processes related to energy, food, and health, which are capable of stimulating new businesses, expanding exports, integrating the value chain and stimulating new demands for innovative products and processes, taking into account health policies. The present article was prepared by a bibliographical survey of the electronic databases PubMed, Lilacs, and Bireme. Cell culture testing can be successfully employed, as it is reproducible, rapid, sensitive, and financially accessible for performing in vitro toxicity testing. Thus, it has been possible to optimize the development phase of new products by decreasing animal use or even replacing them in certain tests. Some in vitro assays validated by the Organization for Economic Cooperation and Development in the area of health products have already replaced animal testing.
Mineral phosphate solubilization activity of gluconacetobacter diazotrophicus under P-limitation and plant root environment  [PDF]
J. M. Crespo, J. L. Boiardi, M. F. Luna
Agricultural Sciences (AS) , 2011, DOI: 10.4236/as.2011.21003
Abstract: The ability to solubilize insoluble inorganic pho- sphate compounds by Gluconacetobacter diazotrophicus was studied using different cul-ture approaches. Qualitative plate assays using tricalcium phosphate as the sole P-source showed that G. diazotrophicus produced solu-bilization only when aldoses were used as the C-source. Extracellular aldose oxidation via a pyrroloquinoline quinone-linked glucose dehy-drogenase (PQQ-GDH) is the main pathway for glucose metabolism in G. diazotrophicus. In batch cultures with 5 g l-1 of hydroxyapatite as the P-source and glucose as the C-source, more than 98% of insoluble P was solubilized. No solubilization was observed neither using glyc-erol nor culturing a PQQ-GDH mutant of G. di-azotrophicus. Solubilizaton was not affected by adding 100 mmol l-1 of MES buffer. Continuous cultures of G. diazotrophicus showed significant activities of PQQ-GDH either under C or P limi-tation. An intense acidification in the root envi-ronment of tomato and wheat seedlings inocu-lated with a G. diazotrophicus PAL5 was ob-served. Seedlings inoculated with a PQQ-GDH mutant strain of G. diazotrophicus showed no acidification. Our results suggest that G. di-azotrophicus is an excellent candidate to be used as biofertilizer because in addition to the already described plant growth-promoting abili-ties of this organism, it shows a significant mineral phosphate solubilization capacity.
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