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High density polyethylene is widely used in many applications which deal with slurry because of its high erosion resistance characteristics. Slurry erosion is a type of erosive wear which takes place when a stream of liquid hits a solid body and results erosion in this body surface. Slurry erosion is affected by some parameters as material hardness, impact velocity, impact angle, slurry content, ambient temperature, particle hardness, particle size and particle shape. The changing of these parameters individually will result in useful analysis for the changing in slurry erosion rate with respect to the changed parameter. This experimental work aims to investigate the slurry erosion behavior of high density polyethylene under the effect of different impact velocities. A slurry impingement test rig will be used to make the wear test and wear rate of HDPE is investigated as a function of impact velocity and impact angle. Results showed that the maximum wear rate is at the lowest impact angle and maximum impact velocity. Weight loss is the indication of wear rate of the HDPE specimens after experiment and wear rate is defined as weight loss during the test time in [mg/h] unit

Energy is the basis of development and a ruler element of economic growth, so securing energy supplies is one of the most pressing issues in the world, in order to protect its national security and secure the needs of future generations. The architect is responsible for designing facilities capable of meeting the needs of its users to provide thermal comfort to accomplish their various activities, Therefore He must take into consideration. A basic aspect to operate the building which is energy saving. The fossil energy on which most buildings operate depend is on its way to depletion and needs many years to be consists they are also polluting the environment, The building sector consumes a very large amount of total energy produced from the world's total energy, especially residential buildings. So that improving energy efficiency in residential buildings through energy efficiency and the use of renewable energy systems in design has become a crucial factor to reduce negative environmental impacts. The main objective of the research is the trend towards environmental conservation and sustainable development by meeting the increasing needs of energy by exploiting environmental resources to produce new clean and renewable energies such as solar and biomass systems that are suitable for new cities, and develop strategies to activate these systems at different levels of design with the application of the principles of sustainable environmental design and bioclimatic architecture where the energy efficiency and rationalization in the building depends on its compatibility with the surrounding climate, and natural ventilation methods which significantly affect the energy consumption of buildings. The research focuses on the new urban communities (the new city of Fayoum) and evaluating the energy efficiency of the existing residential buildings, in addition to test them with energy efficiency assessment programs and presenting models and proposals for environmental and sustainable design to become model cities that are environmentally friendly and energy efficient ,and also represent a design model that can be applied to the future extensions of the city and the rest of the new cities in Egypt which has similar climate.

Origami the ancient art of paper folding has a great effect now, not only on form generation process but also in the development of deployable mechanisms and mimicking the folding systems in nature especially with the great progress in the geometry of folding and computer simulation of the folding process. So it gains a great interest in the field of adaptive architecture, designing open spaces and product design, as it is a source of inspiration for designing configurable structures useful for shed systems that are able to adapt with the changing in the surrounding climate conditions, people’s needs and other surrounding environmental changeable conditions. Also in the design of deployable products that could be packed easily in small spaces and get deployed when needed to save spaces and solve the contemporary problems of small multi-functional spaces. In this research we try to suggest a methodology for designers to get benefit of this art in there designing process, depending on four main sections which are, literature review on the pioneers of this art, the basics of the geometry of folding, computer programs that help in simulating the process of folding and finally methods of fabrication of foldable structures. In the preview of previous studies in the field of architecture analysis have been done with parameters of, static or dynamic, materials and type of folding lines, type of actuator in case of kinematic ones and modularity.

Aims: The present study aims to determine the phototoxic and haemolytic activity of organophosphorus. The use of alternative in vitro assays with human erythrocytes is suggested to predict the polluting effect of these products on health. Methodology: Human erythrocytes from Toluca Blood Bank were used. Sodium dodecyl sulfate was employed as a positive control. Additionally, the haemolysis percentage of three organophosphate (Acetate, Chlorpyrifos, Malathion, Methamidophos, Methyl Parathion) induced photo haemolysis formulated with surfactants on a concentration of 2 x 109 erythrocytes were evaluated. Finally, the products were classified as irritant or phototoxic. Results: Results showed that the HC50 red blood cells were similar for each organophosphate (Malathion and Methamidophos) indicating very irritant action with ratio classification (L/D) of 0.041 and 0.053, respectively. On the other hand, Chlorpyrifos was classified as an irritant with L/D= 0.14. On the other hand, the HC50 obtained photo hemolysis assays irradiated red blood cells was similar for each organophosphate (Acetate, Chlorpyrifos, Malathion, Methamidophos, Methyl Parathion) indicating no phototoxic action. Conclusion: As a conclusion, it can be said that the parameters of haemolysis and denaturation of proteins are good indicators to classify organophosphorus formulated with surfactants as irritating or phototoxic.

This article investigates how universities may evolve into high- or low-performance institutions by taking different approaches to dissent tolerance and processing. We explore different dissent management policies related to growth and productivity. We experiment with a dynamic model of dissent creation and processing in organizations presented in an earlier paper by the authors. Computer simulations with the model suggest that as universities attempt to improve their performance through growth, they may devolve into low-performance institutions with degrading management responsiveness and low organizational productivity. Only when organizations invest in their dissent processing capability will they engage their members productively for improving performance.

This research presents the results of development and validation of the Cyclical Self-Regulated Learning (SRL) Simulation Model, a model of student cognitive and metacognitive experiences learning mathematics within an intelligent tutoring system (ITS). Patterned after Zimmerman and Moylan’s (2009) Cyclical SRL Model, the Simulation Model depicts a feedback cycle connecting forethought, performance and self-reflection, with emotion hypothesized as a key determinant of student learning. A mathematical model was developed in steps, using data collected from students during their sessions within the ITS, developing solutions using structural equation modeling, and using these coefficients to calibrate a System Dynamics (SD) Simulation model. Results provide validation of the Cyclical SRL Model, confirming the interplay of grit, emotion, and performance in the ITS. The Simulation Model enables mathematical simulations depicting a variety of student background types and intervention styles and supporting deeper future explorations of dimensions of student learning.

Objectives: Depression is a common mental disorder, the severity of which is frequently assessed via interview-based clinical scales such as the 7-item Hamilton Depression Rating Scale (HAMD-7). The current study aimed to translate and examine the validity of an Arabic version of the HAMD-7 scale. Methods: This study took place between February and March 2016 in the Psychiatry Department of King Saud University, Riyadh, Saudi Arabia. The HAMD-7 scale was translated into Arabic using forward and backward translation methods. A total of 153 Arabic speakers were recruited to test the translated scale, including 57 medical students and 96 members of the general public. The Arabic version of the HAMD-7 scale was completed by trained investigators during face-toface interviews with the participants. In order to assess convergent validity, participants also completed an Arabic version of the self-assessed Patient Health Questionnaire-9 (PHQ-9) scale. Subsequently, the test-retest reliability of the translated HAMD-7 scale was evaluated two weeks later during a second interview. Results: Overall, HAMD-7 scores were positively correlated with PHQ-9 scores (r = 0.633–0.749). Moreover, the translated HAMD-7 scale proved to be reliable in terms of test-retest reliability (intra-class correlation coefficient: 0.807; P

A simulation model has been developed in this paper to show how a peer-to-peer mentoring setting for sharing work-in-progress research can influence the academic journey of graduate students. The authors have used their personal experience in design, development, and establishment of such a setting to formulate dynamic reference modes of behavior and the model structure. Simulation results show that achieving a balance between smooth graduate research journey, depth of subject matter knowledge, and sharing work-in-progress could be challenging. A hypothetical optimal idea-sharing frequency exists though. We found, through model simulations, that over-sharing, under-sharing, or premature sharing have significant consequences for graduate life. Regardless of its value, keeping the optimal sharing frequency constant might help the students to improve upon their socio-academic life.

Gastric antral vascular ectasia (GAVE) continues to be a challenge in both diagnosis and treatment. GAVE has a diverse group of associations and presumed causes, including cirrhosis, chronic renal failure and autoimmune connective tissue diseases. However, in most occasions, the management plan of GAVE itself is the same whatever the underlying disease by using Argon plasma coagulation (APC). Herein, we will discuss three cases of systemic sclerosis-associated GAVE presenting with either acute or chronic gastrointestinal bleeding showing variable responses to APC. Anemia and telangiectasia may be the first striking presentation of systemic sclerosis (SSc). Renal artery stenosis, aortic stenosis, widespread cutaneous and mucosal telangiectasia and hypertension seem to be associated with poor prognosis and should prompt rapid intervention and careful follow-up. Moreover, the hunt for molecular underpinnings of the broad array of vascular lesions in SSc has to include von Willebrand factor and endoglin. Eventually, we will review the recent alternatives that can be effective in SSc-GAVE, such as band ligation, hematopoietic stem cells transplantation and immunotherapy.

This article proposes a conceptual framework for dissent dynamics in organizations. We integrate the dissent expression and management framework of Kassing with the dynamic institution composition structure of Saeed and Pavlov to construct a generic model for understanding organizational dissent. Our model hypothesizes the impact of dissent accumulation on organizational dissent climate, composition, and performance. Two performance measures comprise the performance grid to describe the current state of an organization and its dissent management policies—perceived management responsiveness and organizational productivity. We argue that dissent expression, tolerance, and management policies affect whether an organization is high or low performing. The conceptual model provides a future platform for experimentation and learning by simulating different policy scenarios and their influence on the paths of change and the new homeostasis eventually achieved by the organization.

This paper reports on a real-life study in a US university. In response to financial issues, the administration at an undergraduate tuition-dependent university pushed for growth in student enrollment. The faculty, who argued that the quality of education had been declining, resisted the expansion. More students also affected the use of the university's infrastructure. By actively engaging key stakeholders, we developed a simple system dynamics model of university expansion. A major insight suggests that policy decisions made non-holistically might result in counter-intuitive outcomes that could take considerable time from which to recover. Copyright © 2016 John Wiley & Sons, Ltd.

Se ha demostrado que los taninos en el follaje de los árboles y arbustos pueden reducir la producción de metano (CH4) en el rumen de los bovinos. Se evaluó el potencial de diez especies de arbustivas, nativas del área templada de México, para reducir la producción de metano a nivel ruminal. Se utilizó la técnica de producción de gas in vitro para evaluar el efecto de la inclusión de estas plantas a tres niveles (10, 20 y 30%) en una dieta experimental. Dos experimentos independientes se hicieron para controlar la producción de gas metano a lo largo de 24 y 72 h de incubación, la producción de metano se registró después de 24 h. Los resultados mostraron una disminución significativa (P

Background Psychological disorders including depression and anxiety are not rare in primary care clinics. The Patient Health Questionnaire (PHQ) is a clinical diagnostic tool that is widely utilized by primary health care physicians worldwide because it provides a practical in-clinic tool to screen for psychological disorders. This study evaluated the validity of the Arabic version of the PHQ in all six modules including depression, anxiety, somatic, panic, eating, and alcohol abuse disorders. Methods This is a quantitative observational cross-sectional study that was conducted by administrating the translated Arabic version of PHQ to a sample of King Saud University students in Riyadh, Saudi Arabia. Results The sample was 731 university students who participated in this study including 376 (51.6%) females and 354 (48.4%) males with a mean age of 21.30 years. Eight mental health experts carried out the face validation process of the PHQ Arabic version. The internal consistency reliability was measured using Cronbach’s alpha for the PHQ9, GAD7, PHQ15, and panic disorder modules. The results were 0.857, 0.763, 0.826, and 0.696, respectively. In comparison, the eating disorders and alcohol abuse modules demonstrated poor internal consistency due to small number of participants in these modules. Conclusion This study demonstrates that the Arabic version of the PHQ is a valid and reliable tool to screen for depression, anxiety, somatic, and panic disorders in a Saudi sample.

Se ha demostrado que los taninos en el follaje de los árboles y arbustos pueden reducir la producción de metano (CH4) en el rumen de los bovinos. Se evaluó el potencial de diez especies de arbustivas, nativas del área templada de México, para reducir la producción de metano a nivel ruminal. Se utilizó la técnica de producción de gas in vitro para evaluar el efecto de la inclusión de estas plantas a tres niveles (10, 20 y 30%) en una dieta experimental. Dos experimentos independientes se hicieron para controlar la producción de gas metano a lo largo de 24 y 72 h de incubación, la producción de metano se registró después de 24 h. Los resultados mostraron una disminución significativa (P

Fahr's disease is a rare idiopathic degenerative neurological disorder, which can be present in different heterogeneous manifestations and characterized by bilateral symmetrical cerebral calcification. These presentations usually involve basal ganglia, manifested with multiple neuropsychiatric disorders. We described a patient with acute onset schizophrenia, who developed abnormal choreoathetoid movement three years later. His brain imaging studies showed extensive bilateral cerebral calcification, the patient was diagnosed with a sporadic case of Fahr's disease. Brain imaging should be considered in acute onset schizophrenia to rule out organic causes. Fahr's disease can be a differential diagnosis when extrapyramidal symptoms and abnormal movement appear and are not improved on treatment

− The aim of this paper is to introduce separation axioms on multiset topological spacesand study some of their properties. Characterization of these spaces and some examples haveinvestigated. Furthermore, we show that such separation axioms are preserved under hereditaryproperties

− In this paper, first we introduce the concepts of semi-open soft mset and semi-closedsoft mset. Then, we discuss some relationships about those concepts. Finally, we introduce thenotion of soft multi semi-compactness as a generalization to soft multi compactness and study theirproperties and theorems

There have been several initiatives by the governments in different parts of the world to establish world-class universities (WCUs). Such initiatives have been attempted only several times and yielded varied results. This article contributes to the existing body of research in architecting WCUs by presenting an operational strategic modeling framework that is grounded in the existing body of literature for developing WCUs (Salmi 2009) which can be used to test assumptions, reveal strategic levers, and analyze dynamic complexity inherent in a task of scaling a start-up university. We present a research study that leveraged stakeholder analysis and system dynamics modeling to architect and test a long-term strategic plan of scaling a newly created Skolkovo Institute of Science and Technology (SkolTech) in Moscow, Russia. We find that the existence of patient capital and favorable governance is conditional on university leadership's ability to effectively manage stakeholder expectations, maintain high-quality standards of its faculty and student population, and protect its brand of a world-class institution. We argue that the operational framework and findings derived from the case of SkolTech can be generalized and applied to other efforts in that area.

This paper utilizes the dynastic cycle framework proposed in (K. Saeed & Pavlov, 2008) to explain the role of dissent in universities. By combining the dissent expression framework (Kassing, 2011) and the dynastic cycle structure, we construct a generic model for dissent in organizations. The work is rooted in the literature of organizational communication, research and development, and higher education management. Using system dynamics methodology, we illustrate the dynamic interaction of composition, climate, and performance to simulate and explain how organizations evolve with regard to dissent. This model provides a platform for experimentation with different policy scenarios focusing on growth and productivity. The research suggests that as universities attempt to improve their performance through growth, despite initial short-term performance improvements, they are likely to devolve into low performance institutions with degraded management responsiveness and organizational productivity. Regardless of having high dissent tolerance, they could become dominated by high control and silence climates. When organizations invest in cultivating a dissent aware climate, and strive to improve their dissent processing capability, we suggest that the university and its members will be more productive and engaged.

新潟大学, 平成17年3月23日, 新大院博（医）第34号, 新大院博（医）甲第34号