Search results for: site effect

Authors: Hussein M. Maghrabie, M. Attalla, Hany. A. Mohamed, M. Salem, E. Specht

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An experimental investigation is carried out on counter-flow Ranque–Hilsch vortex tube (RHVT). The present work is carried out to study the effect of nozzle aspect ratio, tube length and the inlet pressure (P_i) on the coefficient of performance and energy separation of a RHVT. Further, the effect of moist air with different relative humidity (RH) 40, 60, 80 % is also achieved. The air relative humidity is adjusted using air humidification/dehumidification unit. The experimental study accomplished for number of nozzle N=6, with inner diameter D=7.5 mm., and length of the vortex tube (L) 75, 97.5, and 112.5 mm. The results show that the relative humidity has a significant effect on coefficient of performance and energy separation of a RHVT.

Keywords: COP, counter-flow Ranque–Hilsch vortex tube, energy separation, humid air

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Authors: Zhan Zheng-Qun, Li Min, Xie Yan

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Technology plays a key role in determining productivity and economy development in a country. The process of enterprises’ innovation can be seen as a process of knowledge management including the process of knowledge attainment; acquisition and converting and integrating into new knowledge. This research analyzes the influence factors and mechanism of the independent innovation of high-tech enterprises in the year 1995-2013. The result shows that the technology import has a significant positive effect on the innovation capacity of enterprises. And the absorptive capacity, represented by the research outlay input and research staff input, has a significant positive effect on the innovation capacity of enterprises. Furthermore, the effect of technology import on the independent research capacity of high-tech enterprises is significantly positively affected by their absorptive capacity.

Keywords: technology import, innovation capacity, absorptive capacity, high-tech industry

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Authors: F. Ahmed, Y. Dawood

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One of the vehement debates nowadays is about the effect of taxation and economic growth. From one side, taxes are an essential factor to absorb the unemployment, improve the stander of living and achieve a high level of economic growth. On the other hand, they consider it as the main reason to lose the growth ground. The primary goal of the present study is to provide a cross-country evidence of the relationship between taxes and entrepreneurship. There are several important areas where this study makes an original contribution to Entrepreneurship literature. Our paper will use a combination of macro and micro data to present more accurate evidence of the relation. Our study considers large cross sections of countries for the period from 2008 to 2014 for 59 countries. In addition to that and most importantly, our study examines the effect of corruption on the relation between taxes and Entrepreneurship as the corruption is a very important dimension that can explain international entrepreneurship. The importance of this study can be seen from several perspectives: By investigating the taxes effect on entrepreneurship motivation, it is important for the policy makers as well as scholars. Governments and regulators who consider changing in the entrepreneurship sector as an important determinant of economic growth can benefit also from this research. Also, countries who are considering improving their growth level. Scholars also can get insights from this research to gain insights regarding the validity of the Environmental Determinism the institutional theory in the entrepreneurship contest. In addition, it also highlights the obstacles of corruption in developing countries.

Keywords: taxes, corruption, entrepreneurship, across countries

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Authors: Kelum N. Manamendra-Arachchi, Kalangi Rodrigo

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Bones, teeth, and shells have been acknowledged over the last two centuries as evidence of chronology, Palaeo-environment, and human activity. Faunal traces are valid evidence of past situations because they have properties that have not changed over long periods of time. Sri Lanka has been known as an Island, which has a diverse variation of prehistoric occupation among ecological zones. Defining the Paleoecology of the past societies has been an archaeological thought developed in the 1960s. It is mainly concerned with the reconstruction from available geological and biological evidence of past biota, populations, communities, landscapes, environments, and ecosystems. Sri Lanka has dealt with this subject and considerable research has been already undertaken. The fossil and material record of Sri Lanka’s Wet Zone tropical forests continues from c. 38,000–34,000 ybp. This early and persistent human fossil, technical, and cultural florescence, as well as a collection of well-preserved tropical-forest rock shelters with associated ' on-site ' Palaeoenvironmental records, makes Sri Lanka a central and unusual case study to determine the extent and strength of early human tropical forest encounters. Excavations carried out in prehistoric caves in the low country wet zone has shown that in the last 50,000 years, the temperature in the lowland rainforests has not exceeded 5 degrees. Based on Semnopithecus Priam (Gray Langur) remains unearned from wet zone prehistoric caves, it has been argued that periods of momentous climate changes during the LGM and Terminal Pleistocene/Early Holocene boundary, with a recognizable preference for semi-open ‘Intermediate’ rainforest or edges. Continuous Genus Acavus and Oligospira occupation along with uninterrupted horizontal pervasive of Canarium sp. (‘kekuna’ nut) have proven that temperatures in the lowland rain forests have not changed by at least 5 oC over the last 50,000 years. Site Catchment or Territorial analysis cannot be no longer defensible, due to time-distance based factors as well as optimal foraging theory failed as a consequences of prehistoric people were aware of the decrease in cost-benefit ratio and located sites, and generally played out a settlement strategy that minimized the ratio of energy expanded to energy produced.

Keywords: palaeo-environment, prehistory, palaeo-ecology, zooarchaeology

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Authors: Sachin S. Patil, Mohan I. Mehta, Sandip J. Sutar, Akshay B. Patil, Shreyas S. Kirwai, Suresh Arangi

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MnS is the most commonly found inclusion in steel, which is desirable for machinability of alloy steels but only up to a certain limit, beyond which it weakens fatigue properties of steel. In present work, the effect of sulfur content and its inclusions on the fatigue behavior of AISI 4140 steel is studied (sulfur content 0.002% and 0.016%). Metallurgical analysis, Mechanical testing and Rotating Bending Fatigue (RBF) test were carried out. With the increase in sulfur content, ductility and toughness of the material decrease significantly and large scatter is observed in UTS and impact energy values. From the results of RBF testing, it can be observed that increase in sulfur content from 0.002% to 0.016% has a negligible effect on the endurance strength of AISI 4140 for similar hardness level. Fractography analysis was carried out to study the failure modes in testing.

Keywords: AISI 4140, sulfur content, MnS inclusion, rotating bending fatigue

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Authors: Alvin Chun Man Kwok, Wai Sun Chan, Wei Yuan, Joseph Tin Yum Wong

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Cellulose, the most abundant biopolymer, is the major constituent of plant and dinoflagellate cell walls. Thecate dinoflagellates, in particular, are renowned for their remarkable capacity to synthesize intricate cellulosic thecal plates (CTPs). Unlike the extracellular two-dimensional structure of plant cell walls, these CTPs are three-dimensional and reside within the cellular structure itself. The deposition of CTPs occurs with remarkable precision, and their arrangement serves as crucial taxonomic markers. It is noteworthy that these plates possess the hardness of wood, despite the absence of lignin. Partial and prolonged hydrolysis of CTPs results in the formation of uniform long bundles and lowdimensional, modular crystalline whiskers. This observation aligns with the consistent nanomechanical properties, suggesting a CTPboard structure. The unique composition and structural characteristics of CTPs distinguish them from other cellulose-based materials in the natural world. Spectroscopic studies using Raman and FTIR methods indicate a clear low crystallinity index, with the OH shift becoming more distinct following SDS treatment. Birefringence imaging confirms the highly organized structure of CTPs, demonstrating varying degrees of anisotropy in different regions, including both seaward and cytosolic passages. The knockdown of a cellulose synthase enzyme in dinoflagellates resulted in severe malformation of CTPs and hindered the life-cycle transition. Unlike certain other microalgal groups, these unique circum-spherical depositions of CTPs were not pre-fabricated and transported "to site," but synthesized within alveolar sacs at the specific site. Our research is particularly focused on unraveling the mechanisms underlying the biodeposition of CTPs and exploring their potential biotechnological applications. Understanding the processes involved in CTP formation can pave the way for harnessing their unique properties for various practical applications. Dinoflagellates play a crucial role as major agents of algal blooms and are also known for producing anti-greenhouse sulfur compounds such as DMS/DMSP, highlighting the significance of CTPs as a carbon-neutral source of cellulose. Grant acknowledgement: Research in the laboratory are supported by GRF16104523 from Research Grant Council to JTYW.

Keywords: cellulosic thecal plates, dinoflagellates, cellulose, cell wall

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Authors: Vithaya Intraphimol

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The purpose of this study is to investigate the relationship between market orientation and business performance through innovations that include product innovation and process innovation. Auto parts and accessories companies in Thailand were used as sample for this investigation. Survey research with structured questionnaire was used as the key instrument in collecting the data. The structural equation modeling (SEM) was assigned test the hypotheses. The sample size in this study requires the minimum sample size of 200. The result found that competitor orientation, and interfunctional coordination has an effect on product innovation. Moreover, interfunctional coordination has an effect on process innovation, and return on asset. This indicates that within- firm coordination has crucial to firms’ performances. The implication for practice, firms should support interfunctional coordination that members of different functional areas of an organization communicate and work together for the creation of value to target buyers they may have better profitability.

Keywords: auto parts industry, business performance, innovations, market orientation

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Authors: Sudip Subedi, Nipesh Pradhananga

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The musculoskeletal disorders, also known as MSDs, are common in construction workers. MSDs include lower back injuries, knee injuries, spinal injuries, and joint injuries, among others. Since most construction tasks are still manual, construction workers often need to perform repetitive, labor-intensive tasks. And they need to stay in the same or an awkward posture for an extended time while performing such tasks. It induces significant stress to the joints and spines, increasing the risk of getting into MSDs. Manual monitoring of such tasks is virtually impossible with the handful of safety managers in a construction site. This paper proposes a methodology for performing kinetic analysis of the working postures while performing such tasks in real-time. Skeletal of different workers will be tracked using a depth-sensing camera while performing the task to create training data for identifying the best posture. For this, the kinetic analysis will be performed using a human musculoskeletal model in an open-source software system (OpenSim) to visualize the stress induced by essential joints. The “safe posture” inducing lowest stress on essential joints will be computed for different actions involved in the task. The identified “safe posture” will serve as a basis for real-time monitoring and identification of awkward and unsafe postural behaviors of construction workers. Besides, the temporal simulation will be carried out to find the associated long-term effect of repetitive exposure to such observed postures. This will help to create awareness in workers about potential future health hazards and encourage them to work safely. Furthermore, the collected individual data can then be used to provide need-based personalized training to the construction workers.

Keywords: construction workers’ safety, depth sensing camera, human body kinetics, musculoskeletal disorders, real time monitoring, repetitive labor-intensive tasks

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Authors: Lukman Omobola Adisa

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Spelling is rule bound in a written discourse. It, however, calls into question, when such convention is grossly contravened in a formal setting revered as citadel of learning, despite availability of computer spell-checker, human knowledge, and lexicon. The foregoing reveals the extent of decadence pervading education sector in Nigeria. It is on this premise that this study reviews the effect of spelling on communicative competence of the University of Ibadan Registry Staff. The theoretical framework basically evaluates diverse scholars’ views on communicative competence and how spelling influences the intended meaning of a word/ sentence as a result of undue infringement on grammatical (spelling) rule. Newsletter, bulletin, memo, and letter are four print materials purposively selected while the methodology adopted is content analysis. Similarly, five categories, though not limited to, through which spelling blunders are committed are considered: effect of spelling (omission, addition, and substitution); sound ( homophone); transposition (heading/body: content) and ambiguity (capitalisation, space, and acronym). Subsequently, the analyses, findings, and recommendations are equally looked into. Summarily, the study x-rays effective role(s) plays by spelling in enhancing communicative competence through appropriate usage of linguistic registers.

Keywords: communicative competence, content analysis, effect of spelling, linguistics registers

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Authors: Ghadeer A.Al-Jabaree, Husam Aldeen Al-Khadash, M. Nassar

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This study aimed at investigating the effect of well-designed corporate governance system on the financial stability of insurance companies listed in ASE. Further, this study provides a comprehensive model for evaluating and analyzing insurance companies' financial position and prospective for comparing the degree of corporate governance application provisions among Jordanian insurance companies. In order to achieve the goals of the study, a whole population that consist of (27) listed insurance companies was introduced through the variables of (board of director, audit committee, internal and external auditor, board and management ownership and block holder's identities). Statistical methods were used with alternative techniques by (SPSS); where descriptive statistical techniques such as means, standard deviations were used to describe the variables, while (F) test and ANOVA analysis of variance were used to test the hypotheses of the study. The study revealed the existence of significant effect of corporate governance variables except local companies that are not listed in ASE on financial stability within control variables especially debt ratio (leverage),where it's also showed that concentration in motor third party doesn't have significant effect on insurance companies' financial stability during study period. Moreover, the study concludes that Global financial crisis affect the investment side of insurance companies with insignificant effect on the technical side. Finally, some recommendations were presented such as enhancing the laws and regulation that help the appropriate application of corporate governance, and work on activating the transparency in the disclosures of the financial statements and focusing on supporting the technical provisions for the companies, rather than focusing only on profit side.

Keywords: corporate governance, financial stability and solvency margin, insurance companies, Jordan

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Authors: Asif Iqbal

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Working capital management has its effect on liquidity as well as on profitability of a firm. In this research we have selected a sample of 100 respondents whose firms are listed on Karachi stock exchange. We have studied the effect of different variable s of working capital management. We find that organizations throughout the world as well as in Pakistan have to give immense recognition to the working capital management as it is an effective thing from their long term perspective especially to their shareholders to have a firm confidence over the companies for investment purpose.

Keywords: working capital management, Karachi stock exchange, shareholders, capital management

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Authors: Eunjoo Lee

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Background: As the number of surgeries increases, the incidence of adverse events is likely to become more prevalent. Patients who are somewhat knowledgeable about surgery-related adverse events are more likely to engage in safety initiatives to prevent them. Objectives: To evaluate the impact of a smartphone application developed during the study to enhance patients’ knowledge of surgery-related adverse events during hospitalization. Design: Non-randomized, one group, measured pre- and post-intervention. Participants: Thirty-six hospitalized patients admitted to the orthopedics unit of a general hospital in South Korea. Methods. First, a smartphone application to enhance patients’ knowledge of surgery-related adverse events was developed through an iterative process, which included a literature review, expert consultation, and pilot testing. The application was installed on participants’ smartphones, and research assistants taught the participants to use it. Twenty-five true/false questions were used to assess patients’ knowledge of preoperative precautions (eight items), surgical site infection (five items), Foley catheter management (four items), drainage management (four items), and anesthesia-related complications (four items). Results: Overall, the percentage of correct answers increased significantly, from 57.02% to 73.82%, although answers related to a few specific topics did not increase that much. Although the patients’ understanding of drainage management and the Foley catheter did increase substantially after they used the smartphone application, it was still relatively low. Conclusions: The smartphone application developed during this study enhanced the patients’ knowledge of surgery-related adverse events during hospitalization. However, nurses must make an additional effort to help patients to understand certain topics, including drainage and Foley catheter management. Relevance to clinical practice: Insufficient patient knowledge increases the risk of adverse events during hospitalization. Nurses should take active steps to enhance patients’ knowledge of a range of safety issues during hospitalization, in order to decrease the number of surgery-related adverse events.

Keywords: patient education, patient participation, patient safety, smartphone application, surgical errors

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Authors: Giorgi Bregadze

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Tourism is the most viable and sustainable economic development option for Georgia and one of the main sources of foreign exchange earnings. Events are considered as one of the most effective ways to attract foreign visitors to the country, and, recently, the government of Georgia has begun investing in this sector very actively. This article stresses the necessity of research based economic policy in the tourism sector. In this regard, it is of paramount importance to measure the economic effects of the events which are subsidized by taxpayers’ money. The economic effect of events can be analyzed from two perspectives; financial perspective of the government and perspective of economic effects of the tourism administration. The article emphasizes more realistic and all-inclusive focus of the economic effect analysis of the tourism administration as it concentrates on the income of residents and local businesses, part of which generate tax revenues for the government. The public would like to know what the economic returns to investment are. In this article, the methodology used to describe the economic effects of UEFA Super Cup held in Tbilisi, will help to answer this question. Methodology is based on three main principles and covers three stages. Using the suggested methodology article estimates the direct economic effect of UEFA Super cup on Georgian economy. Although the attempt to make an economic effect analysis of the event was successful in Georgia, some obstacles and insufficiencies were identified during the survey. The article offers several recommendations that will help to refine methodology and improve the accuracy of the data. Furthermore, it is very important to receive the correct standard of measurement of events in Georgia. In this caseü non-ethical acts of measurement which are widely utilized by different research companies will not trigger others to show overestimated effects. It is worth mentioning that to author’s best knowledge, this is the first attempt to measure the economic effect of an event held in Georgia.

Keywords: biased economic effect analysis, expenditure of local citizens, time switchers and casuals, UEFA super cup

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Authors: Suparmi, Israhnanto Isradji, Dina Fatmawati, Iwang Yusuf

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Kepel (Stelechocarpus burahol) is one of the traditional plants originating from Indonesia that can be used to prevent pregnancy, launched urine and kidney inflammation. Kepel pulp has compounds alkaloid, triterpenoid, tannin, saponin, and flavonoid, when used will give the hormonal and cytotoxic effect. This study was aimed at evaluating ethanol extract of kepel in vivo for anti-implantation activities. In this experimental study with post test only control group design, 20 female mice were randomly divided into 4 groups. It was divided into the control, the 0,65 mg dose, 1,3 mg dose, and 3,6 mg dose of kepel pulp extract group. The extract soluted in DMSO’s solution and was given 1 ml per mice. The extract was given 10 days before copulation until 18 days of pregnancy. Then, the number of implantation, presence of fetus, and embrio resorbtion were recorded and used to calculate the percentage anti-implantation effect. The results were tested by One-way ANOVA. The mean number of implantation in group control, 0,65 mg;1,3 mg; and 2,6 mg were 5,60±1,14; 6,20± 1,64; 7,60±1,51; 8,00± 1,58, respectively. One way Annova test showed that there is no significant difference in the number of implantation between the group (p > 0,05). The administration of kepel pulp ethanol extract had no effect on the percentage anti-implantation effect and the number of and embrio resorbtion.

Keywords: antiimplantation, fetus, Stelechocarpus burahol, flavonoid

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Authors: Saleh Elawgali

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In order to present the effect of the dynamic eccentricity on the stator currents of squirrel cage induction machines, the current spectrums of a 550 kW induction motor was calculated for the cases of full symmetry and dynamic eccentricity. The calculations presented in this paper are based on the Poly-Harmonic Model accounting for static and dynamic eccentricity, stator and rotor slotting, parallel branches as well as cage asymmetry. The calculations were followed by Fourier analysis of the stator currents in steady state operation. The paper presents the stator current spectrums for full symmetry and dynamic eccentricity cases, and demonstrates the harmonics present in each case. The effect of dynamic eccentricity is demonstrating via comparing the current spectrums related to dynamic eccentricity cases with the full symmetry one.

Keywords: current spectrum, dynamic eccentricity, harmonics, Induction machine, slot harmonic zone.

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Authors: Nassima Behidj-Benyounes, Thoraya Dahmene, Nadjiba Chebout

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This work examines the study of the antimicrobrial effect of alkaloids extracted from the seeds of Peganum harmala L (Zygophyllaceae). This natural substance is extracted by using different solvents (aqueous, ethanolic, and hexane). The evaluation of the antimicrobial activity has only dealt with alkaloids. The antimicrobial effect of alkaloids is evaluated on several microorganisms. It has been tested on eight bacterial strains. The extract has been studied by using two yeasts. Finally, three molds have been studied. It should be noted that these agents are characterized by a high frequency of contamination and pathogenicity. Through this study, we note that Staphylococcus aureus, Saccharomyces cerievisae and E. coli are very sensitive in respect of the ethanol extract. Pseudomonas aerogenosa and Penicillium sp. are resistant to this extract. The other microorganisms are moderately sensitive. The study of the antimicrobial activity of different extracts of the Harmel has shown an optimal activity with the ethanol extract.

Keywords: Peganum harmala L., seeds, alkaloids, bacteria, fungi, yeast, antimicrobial activity

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Authors: I. Ketut Yoga Adityawira, Putu Ayu Novia Viorica, Komang Rahayu Indrawati

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In addition to work and take care of the family, Balinese women also have a role to participate in social activities in Bali. So this will have an impact on the quality of work life of Balinese women. One way to reduce the impact of the fulfillment of the role of Balinese women namely through emotional support. The aim of this research is to find out the effect of emotional support towards the quality of work life on Balinese working women. Data were retrieved by quasi-experimental method with pretest-posttest design. Data were analyzed by Analysis of Variance (ANOVA) through SPSS 17.0 for Windows. The number of subjects in this research is 30 people with the criteria: Balinese Women, aged 27 to 55 years old, have a minimum of two years experience of work and has been married. The analysis showed that there is no effect of emotional support towards the quality of work life on Balinese working women, with information there is no significant of probability value p = 0.304 (p > 0.05).

Keywords: Balinese women, emotional support, quality of work life, working women

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Authors: Samir Ali-arous, Mohamed Beddane, Khaled Djelouah

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This study investigated the insect diversity of olive (Olea europaea Linnaeus (Oleaceae)) groves grown in an arid climate in Algeria. In this context, several sampling methods were used within two orchards differently managed. Fifty arthropod species belonging to diverse orders and families were recorded. Hymenopteran species were quantitatively the most abundant, followed by species associated with Heteroptera, Aranea, Coleoptera and Homoptera orders. Regarding functional feeding groups, phytophagous species were dominant in the weeded and the unweeded orchard; however, higher abundance was recorded in the weeded site. Predators were ranked second, and pollinators were more frequent in the unweeded olive orchard. Two-factor Anova with repeated measures had revealed high significant effect of the weed management system, measures repetition and interaction with measurement repetition on arthropod’s abundances (P < 0.05). Likewise, generalized linear models showed that N/S ratio varied significantly between the two weed management approaches, in contrast, the remaining diversity indices including the Shannon index H’ had no significant correlation. Moreover, diversity parameters of arthropod’s communities in each agro-system highlighted multiples significant correlations (P <0.05). Rarefaction and extrapolation (R/E) sampling curves, evidenced that the survey and monitoring carried out in both sites had a optimum coverage of entomofauna present including scarce and transient species. Overall, calculated diversity and similarity indices were greater in the unweeded orchard than in the weeded orchard, demonstrating spontaneous flora's key role in entomofaunal diversity. Principal Component Analysis (PCA) has defined correlations between arthropod’s abundances and naturally occurring plants in olive orchards, including beneficials.

Keywords: Algeria, olive, insects, diversity, wild plants

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Authors: Olga S. Volodko, Lidiya A. Kompaniets, Ludmila V. Gavrilova

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The method of empirical orthogonal functions is the method of data analysis with a complex spatial-temporal structure. This method allows us to decompose the data into a finite number of modes determined by empirically finding the eigenfunctions of data correlation matrix. The modes have different scales and can be associated with various physical processes. The empirical orthogonal function method has been widely used for the analysis of hydrophysical characteristics, for example, the analysis of sea surface temperatures in the Western North Atlantic, ocean surface currents in the North Carolina, the study of tropical wave disturbances etc. The method used in this study has been applied to the analysis of temperature and velocity measurements in saline Lake Shira (Southern Siberia, Russia). Shira is a shallow lake with the maximum depth of 25 m. The lake Shira can be considered as a closed water site because of it has one small river providing inflow and but it has no outflows. The main factor that causes the motion of fluid is variable wind flows. In summer the lake is strongly stratified by temperature and saline. Long-term measurements of the temperatures and currents were conducted at several points during summer 2014-2015. The temperature has been measured with an accuracy of 0.1 ºC. The data were analyzed using the empirical orthogonal function method in the real version. The first empirical eigenmode accounts for 70-80 % of the energy and can be interpreted as temperature distribution with a thermocline. A thermocline is a thermal layer where the temperature decreases rapidly from the mixed upper layer of the lake to much colder deep water. The higher order modes can be interpreted as oscillations induced by internal waves. The currents measurements were recorded using Acoustic Doppler Current Profilers 600 kHz and 1200 kHz. The data were analyzed using the empirical orthogonal function method in the complex version. The first empirical eigenmode accounts for about 40 % of the energy and corresponds to the Ekman spiral occurring in the case of a stationary homogeneous fluid. Other modes describe the effects associated with the stratification of fluids. The second and next empirical eigenmodes were associated with dynamical modes. These modes were obtained for a simplified model of inhomogeneous three-level fluid at a water site with a flat bottom.

Keywords: Ekman spiral, empirical orthogonal functions, data analysis, stratified fluid, thermocline

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Authors: M. A. Akhavan-Behabadi, M. Najafi, A. Abbasi

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An empirical investigation was performed in order to study the heat transfer characteristics of R600a flow boiling inside horizontal flattened tubes and the simultaneous effect of nanoparticles on boiling heat transfer in flattened channel. Round copper tubes of 8.7 mm I.D. were deformed into flattened shapes with different inside heights of 6.9, 5.5, and 3.4 mm as test areas. The effect of different parameters such as mass flux, vapor quality and inside height on heat transfer coefficient was studied. Flattening the tube caused significant enhancement in heat transfer performance so that the maximum augmentation ratio of 163% was obtained in flattened channel with lowest internal height. A new correlation was developed based on the present experimental data to predict the heat transfer coefficient in flattened tubes. This correlation estimated 90% of the entire database within ±20%.

Keywords: nano particles, flattend tube, R600a, CuO

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Authors: Azli Bin Ariffin, Noor Amy Afiza Binti Mohd Yusof

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This study aims to identify effect of social network usage on the self-learning method in teaching and learning at Sultan Idris Education University. The study involved 270 respondents consisting of students in the pre-graduate and post-graduate levels from nine fields of study offered. Assessment instrument used is questionnaire which measures respondent’s background includes level of study, years of study and field of study. Also measured the extent to which social pages used for self-learning and effect received when using social network for self-learning in learning process. The results of the study showed that students always visit Facebook more than other social sites. But, it is not for the purpose of self-learning. Analyzed data showed that 45.5% students not sure about using social sites for self-learning. But they realize the positive effect that they will received when use social sites for self-learning to improve teaching and learning process when 72.7% respondent agreed with all the statements provided.

Keywords: facebook, self-learning, social network, teaching, learning

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Authors: B. Medjadji, L. Aminallah, B. Serier, M. Benlebna

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In this study, the finite element method in 3-D is used to calculate the integral J in the semi-elliptical crack in a pipe subjected to internal pressure. The stress-strain curve of the pipe has been determined experimentally. The J-integral was calculated in two fronts crack (Ф = 0 and Ф = π/2). The effect of the configuration of the crack on the J integral is analysed. The results show that an external longitudinal crack in a pipe is the most dangerous. It also shows that the increase in the applied pressure causes a remarkable increase of the integral J. The effect of the depth of the crack becomes important when the ratio between the depth of the crack and the thickness of the pipe (a / t) tends to 1.

Keywords: J integral, pipeline, crack, MEF

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Authors: Nabaouia.Maktouf, Ali Ben Moussa, Saïd Turki

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This paper discusses the effect of an attached flexible membrane on the control of fluid around a circular cylinder. A parametric study has been investigated for different positions, sizes, modes as well as frequencies of oscillation of the flexible membrane. The numerical investigation was conducted for a Reynolds number equal to 150 using the commercial code Fluent 16.0 and parallel calculation into 4 processors. The motion of the flexible membrane was managed by the dynamic mesh and compiled into Fluent as a user-defined function. The first part of this paper discusses the effect of changing the position of a flexible membrane sized 8° as an angle of aperture on the aerodynamic coefficients. Results show that the flexible membrane placed at 110° from the stagnation point presents more non-linearity on the behavior of the drag coefficient compared to the drag behavior when placed at 180°, relative to the stagnation point. The effect of the size of the flexible surface was studied for the corresponding angles of aperture: 32° and 42°, respectively. The effect of modes (modes 1, 2, and 3) of vibrations has been investigated at a constant frequency of vibration f=2Hz for angles 32° and 42°. All the calculations have been done with a constant amplitude A =0.001m. A non-linearity of the drag coefficient was clearly observed for all the sizes, modes as well as frequencies of excitation. The Fast Fourier transformation shows the appearance of the natural shedding frequency and the multiples of the frequency of excitation. An increase in the modes of oscillation leads to a more linear behavior of the drag coefficient.

Keywords: fluid flow control, numerical simulation, dynamic mesh, aerodynamic forces, flexible membrane

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Authors: Stefano A. Denes, Riccardo Tieghi, Giovanni Elia

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The buccal fat pad is a well-established tool in oral and maxillofacial surgery and its use has proved of value for the closure of oroantral communications. Oroantral communication may be a common complication after sequestrectomy in "Bisphosphonate-related osteonecrosis of the jaws". We report a clinical case of a 70-year-old female patient in bisphosphonate therapy presented with right maxillary sinusitis and oroantral communication after implants insertion. The buccal fat pad was used to close the defect. The case had an uneventful postoperative healing without dehiscence, infection and necrosis. We postulate that the primary closure of the site with buccal fat pad may ensure a sufficient blood supply and adequate protection for an effective bone-healing response to occur.

Keywords: buccal fat pad, oroantral communication, oral surgery, dehiscence

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Authors: Agnieszka Stempniewicz, Piotr Ceranowicz, Wojciech Macyk, Jakub Cieszkowski, Beata Kuśnierz-Cabała, Katarzyna Gałązka, Zygmunt Warzecha

Abstract:

Objectives: There are numerous strategies for the prevention or treatment of oral mucositis. However, their effectiveness is limited and does not correspond to expectations. Recent studies have shown that obestatin exhibits a protective effect and accelerates the healing of gastrointestinal mucosa. The aim of the present study was to examine the influence of obestatin administration on oral ulcers in rats. Methods: lingual ulcers were induced by the use of acetic acid. Rats were treated twice a day intraperitoneally with saline or obestatin(4, 8, or 16 nmol/kg/dose) for five days. The study determined: lingual mucosa morphology, cell proliferation, mucosal blood flow, and mucosal pro-inflammatory interleukin-1β level(IL-1β). Results: In animals without induction of oral ulcers, treatment with obestatin was without any effect. Obestatin administration in rats with lingual ulcers increased the healing rate of these ulcers. Obestatin given at the dose of 8 or 16 nmol/kg/dose caused the strongest and similar therapeutic effect. This result was associated with a significant increase in blood flow and cell proliferation in gingival mucosa, as well as a significant decrease in IL-1β level. Conclusions: Obestatin accelerates the healing of lingual ulcers in rats. This therapeutic effect is well-correlated with an increase in blood flow and cell proliferation in oral mucosa, as well as a decrease in pro-inflammatory IL-1β levels. Obestatin is a potentially useful candidate for the prevention and treatment of oral mucositis. Acknowledgment: Agnieszka Stempniewicz acknowledges the support of InterDokMed project no. POWR.03.02.00- 00-I013/16.

Keywords: oral mucositis, ulcers, obestatin, lingual mucosa

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Authors: Zhang Haitao

Abstract:

The different size of nanoparticle mordenite zeolites were prepared by adding different soft template during hydrothermal process for carbonylation of dimethyl ether (DME) to methyl acetate (MA). The catalysts were characterized by X-ray diffraction, Ar adsorption-desorption, high-resolution transmission electron microscopy, NH3-temperature programmed desorption, scanning electron microscopy and Thermogravimetric. The characterization results confirmed that mordenite zeolites with small nanoparticle showed more strong acid sites which was the active site for carbonylation thus promoting conversion of DME and MA selectivity. Furthermore, the nanoparticle mordenite had increased the mass transfer efficiency which could suppress the formation of coke.

Keywords: nanoparticle mordenite, carbonylation, dimethyl ether, methyl acetate

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Authors: Sangeeta Pilkhwal Sah, C. S. Mathela, Kanwaljit Chopra

Abstract:

Valeriana wallichii DC, an ayurvedic traditional medicine, popularly named as Indian valerian exist as three chemotypes. GC-MS analysis of V. wallichii essential oil in present study showed maaliol as the major constituent followed by the presence of β-gurjunene, acoradiene, guaiol and α-santalene. The results thus confirmed it to be a maaliol chemotype. Further, the antidepressant-like effect of root essential oil (10, 20 and 40 mg/kg p.o.) was investigated in both acute and chronic treatment study using forced swim test in mice. Single administration of different doses produced an inverted U shaped curve and significantly inhibited the immobility period (39.7% and 58%) at doses 10 and 40 mg/kg respectively. Standard drug imipramine significantly decreased immobility period (59.8%). None of the doses altered locomotor activity except a significant decrease of 44.9% was observed with 40 mg/kg (p < 0.05). Similarly, daily administration of essential oil for 14 days produced a dose dependent effect with significantly reduced immobility period (70.9%) at 40 mg/kg dose only whereas imipramine produced 86% decrease (p < 0.05). The neurotransmitter levels in mouse brain were estimated on day 14 after the behavioral study. Significant increase in the level of norepinephrine (10%) and dopamine (23%) (p < 0.05) was found at 40 mg/kg dose, while no change was observed at 10 and 20 mg/kg doses. The antidepressant-like effect of essential oil (40 mg/kg) was prevented by pretreatment of mice with L-arginine (750 mg/kg i.p.) and sildenafil (5 mg/kg i.p). On the contrary, pretreatment of mice with L-NAME (10 mg/kg i.p.) or methylene blue (10 mg/kg i.p.) potentiated the antidepressant action of essential oil (20 mg/kg). The findings thus demonstrated that nitric oxide pathway is involved in mediating antidepressant like effect of essential oil from this chemotype.

Keywords: Valeriana wallichii DC chemotype, essential oil, forced swim test, nitric oxide modulators, neurotransmitters

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Authors: Bingqing Xu, Wenxing Shuai

Abstract:

This study investigates the priming effects of different Chinese compound words by native Mandarin speakers. There are lots of homonym, polysemy, and synonym in Chinese. However, it is unclear which kind of words have the biggest priming effect. Native Mandarin speakers were tested in a visual-word lexical decision experiment. The stimuli, which are all two-character compound words, consisted of two parts: primes and targets. Five types of relationships were used in all stimuli: morphologically related condition, in which the prime and the target contain the same morpheme; orthographically related condition, in which the target and the prime contain the different morpheme with the same form; phonologically related condition, in which the target and the prime contain the different morpheme with the same phonology; semantically related condition, in which the target and the prime contain the different morpheme with similar meanings; totally unrelated condition. The time since participants saw the target to respond was recorded. Analyses on reaction time showed that the average reaction time of morphologically related targets was much shorter than others, suggesting the morphological priming effect is the biggest. However, the reaction time of the phonologically related conditions was the longest, even longer than unrelated conditions. According to scatter plots analyses, 86.7% of participants had priming effects in morphologically related conditions, only 20% of participants had priming effects in phonologically related conditions. These results suggested that morphologically related conditions had the biggest priming effect. The orthographically and semantically related conditions also had priming effects, whereas the phonologically related conditions had few priming effects.

Keywords: priming effect, morphology, phonology, semantics, orthography

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Authors: Ediati Budi Cahyono, Triana Hertiani, Nauval Arrazy Asawimanda, Wahyu Puji Pratomo

Abstract:

Background: Doxorubicin is widely used as a chemotherapeutic drug despite having many side effects. It may cause macrophage dysfunction and decreasing proliferation of lymphocyte. Noni (Morinda citrifolia) fruit which has rich of polysaccharide content has potential as antitumor and immunostimulant effect. The isolation of polysaccharide from Noni fruit has been optimized according to four different methods based on macrophage and lymphocyte activities. We found the highest polysaccharide content from one of the four methods isolation. A method of polysaccharide isolation which has the highest immunostimulant effect was used for further observation as co-chemotherapy. The aim of the study: was to evaluate the isolated polysaccharide from the method of choice as co-chemotherapy of doxorubicin for the growth of Vero, He-La, and T47D cell lines in vitro. The method: in vitro growth assay of Vero, He-La, and T47D cell lines was done using MTT-reduction method, and apoptosis test was done by double staining method to evaluate the induction apoptotic effect of the combination. Every group was treated with doxorubicin and isolated polysaccharide from method of choice with 4 variances of concentrations (25 µg/ml, 50 µg/ml, 100 µg/ml and 200 µg/ml) a long with negative control (doxorubicin only) and normal control (without doxorubicin or polysaccharide administration). Results: The combination of polysaccharide fraction in the concentration of 100μg/ml with 2μmol of doxorubicin against He-La and T47D cell lines influenced the highest cytotoxic effect by suppressing cell viability comparing with doxorubicin only. The combination of polysaccharide fraction in the concentration of 100μg/ml with 2μmol of doxorubicin-induced apoptotic effect the He-La cell line comparing with doxorubicin only. The result of the study: it can be concluded that the combination of polysaccharide fraction and doxorubicin effect more selective toward He-La and T47D cell lines than to Vero cell line. It can be suggested isolated polysaccharide from the method of choice has co-chemotherapy activity against doxorubicin.

Keywords: polysaccharide, noni fruit, doxorubicin, cancer cell lines, vero cell line

Procedia PDF Downloads 254

Authors: Wenjuan Du, Jingtian Bi, Tong Wang, Haifeng Wang

Abstract:

Grid connection of a large-scale wind farm affects power system small-signal angular stability in two aspects. Firstly, connection of the wind farm brings about the change of load flow and configuration of a power system. Secondly, the dynamic interaction is introduced by the wind farm with the synchronous generators (SGs) in the power system. This paper proposes a method to assess the two aspects of the effect of the wind farm on power system small-signal angular stability. The effect of the change of load flow/system configuration brought about by the wind farm can be examined separately by displacing wind farms with constant power sources, then the effect of the dynamic interaction of the wind farm with the SGs can be also computed individually. Thus, a clearer picture and better understanding on the power system small-signal angular stability as affected by grid connection of the large-scale wind farm are provided. In the paper, an example power system with grid connection of a wind farm is presented to demonstrate the proposed approach.

Keywords: power system small-signal angular stability, power system low-frequency oscillations, electromechanical oscillation modes, wind farms, double fed induction generator (DFIG)

Procedia PDF Downloads 485