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Copolymerization of ethylene and 1-octene was carried out using a Ziegler-Natta catalyst and the optimization of copolymerization conditions was studied. The optimum polymerization activity was obtained at 60 °C and [Al]:[Ti] molar ratio of 143:1. It was observed that the increase in the comonomer ratio in the feedstock influenced the physical properties of the final copolymer obtained. The results showed a range of crystallinity (Xc) from 68.5% to 34.8% and a range of melting temperature (Tm) from 140 °C to 129 °C for the synthesized copolymers. The viscosity average molecular weight (M̅v) of the polymers decreased as the polymerization temperature increased, however, by increasing the monomer pressure, the M̅v of the polymers and the catalyst activity increased. Polymer nanocomposites containing graphene and multi-walled carbon nanotubes with different particle sizes were prepared under the optimum copolymerization conditions. The addition of graphene and multi-walled carbon nanotubes decreased the activity of the catalyst. However, the thermal stability, and crystallinity of the polymers were found to be increased. [ABSTRACT FROM AUTHOR]

Family Carangidae is widely distributed in the Atlantic, Indian and pacific Oceans. Two morphologically similar species, Trachurus indicus and Decapterus maruadsi, were collected and recognized from the Gulf of Suez. The two species have no distinct differences morphologically. Microsatellite DNA markers revealed that the populations of the two species represented distinct genetic divergence. This genetic diversity study showed that the populations of the two species are not related to each other. Overall, this study reveals high genetic diversity of T. indicus and D. maruadsi populations. Further studies on the genetic structure of these two species, are needed not only to understand the evolutionary history of the species, but also to improve the knowledge-based fishery management programs of this important biological resources. [ABSTRACT FROM AUTHOR]

Background and Objectives: Traditionally, diagnosis of the agents of infectious diseases is based on conventional or phenotypic methods. Due to the lack of growth of some infectious agents, these methods are very difficult or impossible for diagnosis of some bacteria. The advent of molecular techniques has more or less influences on the detection of microbial infections. This article addresses the advantages and disadvantages of diagnostic molecular and conventional methods in detecting pathogenic microorganisms. Traditional diagnostic methods such as phenotypic, chemical and serologic characteristics are still used for detection of infectious diseases. In addition to diagnosing the bacterial agents, varient molecular methods may also detect virulence factors and antimicrobial resistance genes at a higher rate, sensitivity and accuracy. It seems that the advanced molecular methods can reduce diagnosis time, mortality rate and costs of laboratory diagnosis, and shorten the duration of hospitalization. [ABSTRACT FROM AUTHOR]

Background and Objective: Studies in the health sciences is comprised of observational and intervention. A major part of health sciences research has been allocated to the observational studies. Designing and doing studies based on scientific guidelines that include the entire process, leads to studies validation and also results can be generalized to the community. Thus, for standardizing the scientific and observational studies, a statement entitled "Strengthening the Reporting of Observational Studies in Epidemiology" (STROBE) was presented. The purpose of drafting a STROBE statement, is making recommendations to clarify the design, methods, and findings of observational studies and is not requiring researchers to follow a particular methodology. In other words, the purpose of the STROBE statement is better "reporting" of observational studies and not better "doing". According to the importance of designing and scientific reporting of observational articles, this study was performed for presentation of the STROBE statement, history, goals, and weaknesses for Persian speaking readers. Materials and Methods: To verify the STROBE statement, STROBE website and published articles on the evaluation of STROBE effectiveness and related articles were studied. Results: The results of this study showed the lack of adequate use of STROBE statement in the articles published after the presentation of this statement. Conclusion: Knowledge of the scientific standards for reporting research in Iran to enhance the academic standing and the quality of research, leads to improved academic standing of the Iranian specialists in the world. [ABSTRACT FROM AUTHOR]

P. Mederly [7] characterized the modular pseudocomplemented semilattices in terms of triples. We show that a similar result is possible for the class of quasi-modular pseudocomplemented semilattices, which is an extension of the class of modular pseudocomplemented semilattices. [ABSTRACT FROM AUTHOR]

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Nanoparticles of Ni0.92Ca0.08Fe2O4 ferrite was prepared by the citrate precursor method. The effect of sintering temperature and sintering time on the structural, magnetic, and thermal properties of the prepared samples were investigated by using x-ray diffraction (XRD) and transmission electron microscope (TEM), vibrating sample magnetometer (VSM), and photoacoustic (PA) technique, respectively. The grain size of the sintered samples estimated from the XRD and the TEM results inform that the increase in the particle size is more announced by increasing the sintering temperature than increasing the sintering time. The unexpected decrease of the saturation magnetization of the sintered samples is ascribed to the dominant effect of the cation distribution which is affected by the sintering process. The cation distribution of the present samples was obtained from the analysis of the magnetization measurements and XRD data. The increase of measured density and the decrease of porosity of the sintered samples as a result of the grain growth have the obvious effect of increasing their thermal diffusivity. [ABSTRACT FROM AUTHOR]

Hospital library Websites are now becoming a commonly implemented means of providing access to health information to a diverse group of patrons. Hospital libraries must design their Websites to effectively serve patrons' information needs. Usability testing is a validated method of evaluating a library's Website design. Usability testing enables the opportunity to observe and evaluate real-world Website navigation. Usability testing provides a challenge for many hospital librarians. Hierarchical Goal Decomposition (HGD) provides a means to leverage a user's knowledge base or augment a deficit of knowledge to achieve a fruitful experience at the hospital's Website. This paper documents the use of HGD to analyze Genetic Home Reference, a resource available through the National Library of Medicine. Through this work, this paper provides guidelines for individual hospital librarians to utilize HGD to inform Website design for a hospital or hospital library Website. Although labor-intensive, HGD can provide information of a high degree of granularity with a smaller sample size that delivers high quality information. [ABSTRACT FROM AUTHOR]

OBJECTIVE: The article offers a current perspective on medical informatics and health sciences librarianship. NARRATIVE: The authors: (1) discuss how definitions of medical informatics have changed in relation to health sciences librarianship and the broader domain of information science; (2) compare the missions of health sciences librarianship and health sciences informatics, reviewing the characteristics of both disciplines; (3) propose a new definition of health sciences informatics; (4) consider the research agendas of both disciplines and the possibility that they have merged; and (5) conclude with some comments about actions and roles for health sciences librarians to flourish in the biomedical information environment of today and tomorrow. SUMMARY: Boundaries are disappearing between the sources and types of and uses for health information managed by informaticians and librarians. Definitions of the professional domains of each have been impacted by these changes in information. Evolving definitions reflect the increasingly overlapping research agendas of both disciplines. Professionals in these disciplines are increasingly functioning collaboratively as 'boundary spanners,' incorporating human factors that unite technology with health care delivery. [ABSTRACT FROM AUTHOR]