Search results for: negative media influence
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 14190

Search results for: negative media influence

2520 The Impact of Effective Employee Retention Strategies to the Success of the Hotel Industry of Rwanda

Authors: Ange Meghane Hakizimana, Landry Ndikuriyo

Abstract:

Retention of employees in the hospitality industry is a recurrent agenda in the organization involving all the combined efforts to maintain the best available laborer. The general objective of this research is to assess the impact of effective employee retention strategies on the success of the hotel industry at Galileo Hotel, Huye District in Rwanda, for the period of 2019-2021. Herzberg Two Factor Theory and Equity Theory were used. The study adopted a descriptive research design. Descriptive research design allowed us to study the elements in their natural form without making any alterations to them. Secondary data and primary data and the data collected were sorted and entered into the statistical packages for social sciences for analysis (SPSS) version 26. Frequencies, descriptive statistics and percentages were used to analyze and establish extent to which employee retention strategies impact the success of the hotel industry of Rwanda and this was analyzed using regression and correlation analysis. The results revealed that employee training and development had an influence of 24.8% on the success of the hotel industry in Rwanda. According to the results of our study, the employee reward system contributes 20.7% to the success of the hotel industry in Rwanda, the value of t is 3.475 and this is greater than the standard t value score of 1.96, p-value is 0.002. Therefore the employee reward system has a great positive impact on the success of the hotel industry in Rwanda. The results also show that 15.7% of the success of the hospitality industry in Rwanda is due to the work environment of employees. With a t-value of 4.384 and a p-value of 0.000, the above statistics show a positive impact of the employees' working environment on success of the hospitality industry in Rwanda. A priority to the retention of their employees should be given by the hotel industry and its managers because it has already been proven that it is an effective approach to offering good customer service. In addition, employee retention reduces expenses associated with employee recruitment and turnover.

Keywords: success, hotel industry, training and development, employee reward system, employee work environment

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2519 Investigating Elements That Influence Higher Education Institutions’ Digital Maturity

Authors: Zarah M. Bello, Nathan Baddoo, Mariana Lilley, Paul Wernick

Abstract:

In this paper, we present findings from a multi-part study to evaluate candidate elements reflecting the level of digital capability maturity (DCM) in higher education and the relationship between these elements. We will use these findings to propose a model of DCM for educational institutions. We suggest that the success of learning in higher education is dependent in part on the level of maturity of digital capabilities of institutions as well as the abilities of learners and those who support the learning process. It is therefore important to have a good understanding of the elements that underpin this maturity as well as their impact and interactions in order to better exploit the benefits that technology presents to the modern learning environment and support its continued improvement. Having identified ten candidate elements of digital capability that we believe support the level of a University’s maturity in this area as well as a number of relevant stakeholder roles, we conducted two studies utilizing both quantitative and qualitative research methods. In the first of these studies, 85 electronic questionnaires were completed by various stakeholders in a UK university, with a 100% response rate. We also undertook five in-depth interviews with management stakeholders in the same university. We then utilized statistical analysis to process the survey data and conducted a textual analysis of the interview transcripts. Our findings support our initial identification of candidate elements and support our contention that these elements interact in a multidimensional manner. This multidimensional dynamic suggests that any proposal for improvement in digital capability must reflect the interdependency and cross-sectional relationship of the elements that contribute to DCM. Our results also indicate that the notion of DCM is strongly data-centric and that any proposed maturity model must reflect the role of data in driving maturity and improvement. We present these findings as a key step towards the design of an operationalisable DCM maturity model for universities.

Keywords: digital capability, elements, maturity, maturity framework, university

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2518 Kinetic, Equilibrium and Thermodynamic Studies of the Adsorption of Crystal Violet Dye Using Groundnut Hulls

Authors: Olumuyiwa Ayoola Kokapi, Olugbenga Solomon Bello

Abstract:

Dyes are organic compounds with complex aromatic molecular structure that resulted in fast colour on a substance. Dye effluent found in wastewater generated from the dyeing industries is one of the greatest contributors to water pollution. Groundnut hull (GH) is an agricultural material that constitutes waste in the environment. Environmental contamination by hazardous organic chemicals is an urgent problem, which is partially solved through adsorption technologies. The choice of groundnut hull was promised on the understanding that some materials of agricultural origin have shown potentials to act as Adsorbate for hazardous organic chemicals. The aim of this research is to evaluate the potential of groundnut hull to adsorb Crystal violet dye through kinetic, isotherm and thermodynamic studies. The prepared groundnut hulls was characterized using Brunauer, Emmett and Teller (BET), Fourier transform infrared (FTIR) and scanning electron microscopy (SEM). Operational parameters such as contact time, initial dye concentration, pH, and effect of temperature were studied. Equilibrium time for the adsorption process was attained in 80 minutes. Adsorption isotherms used to test the adsorption data were Langmuir and Freundlich isotherms model. Thermodynamic parameters such as ∆G°, ∆H°, and ∆S° of the adsorption processes were determined. The results showed that the uptake of dye by groundnut hulls occurred at a faster rate, corresponding to an increase in adsorption capacity at equilibrium time of 80 min from 0.78 to 4.45 mg/g and 0.77 to 4.45mg/g with an increase in the initial dye concentration from 10 to 50 mg/L for pH 3.0 and 8.0 respectively. High regression values obtained for pseudo-second-order kinetic model, sum of square error (SSE%) values along with strong agreement between experimental and calculated values of qe proved that pseudo second-order kinetic model fitted more than pseudo first-order kinetic model. The result of Langmuir and Freundlich model showed that the adsorption data fit the Langmuir model more than the Freundlich model. Thermodynamic study demonstrated the feasibility, spontaneous and endothermic nature of the adsorption process due to negative values of free energy change (∆G) at all temperatures and positive value of enthalpy change (∆H) respectively. The positive values of ∆S showed that there was increased disorderliness and randomness at the solid/solution interface of crystal violet dye and groundnut hulls. The present investigation showed that, groundnut hulls (GH) is a good low-cost alternative adsorbent for the removal of Crystal Violet (CV) dye from aqueous solution.

Keywords: adsorption, crystal violet dye, groundnut halls, kinetics

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2517 Effect of Z-VAD-FMK on in Vitro Viability of Dog Follicles

Authors: Leda Maria Costa Pereira, Maria Denise Lopes, Nucharin Songsasen

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Mammalian ovaries contain thousands of follicles that eventually degenerate or die after culture in vitro. Caspase-3 is a key enzyme that regulating cell death. Our objective was to examine the influence of anti-apoptotic drug Z-VAD-FMK (pan-caspase inhibitor) on in vitro viability of dog follicles within the ovarian cortex. Ovaries were obtained from prepubertal (age, 2.5–6 months) and adult (age, 8 months to 2 years) bitches and ovarian cortical fragments were recovered. The cortices were then incubated on 1.5% (w/v) agarose gel blocks within a 24-wells culture plate (three cortical pieces/well) containing Minimum Essential Medium Eagle - Alpha Modification (Alpha MEM) supplemented with 4.2 µg/ml insulin, 3.8 µg/ml transferrin, 5 ng/ml selenium, 2 mM L-glutamine, 100 µg/mL of penicillin G sodium, 100 µg/mL of streptomycin sulfate, 0.05 mM ascorbic acid, 10 ng/mL of FSH and 0.1% (w/v) polyvinyl alcohol in humidified atmosphere of 5% CO2 and 5% O2. The cortices were divided in six treatment groups: 1) 10 ng/mL EGF (EGF V0); 2) 10 ng/mL of EGF plus 1 mM Z-VAD-FMK (EGF V1); 3) 10 ng/mL of EGF and 10 mM Z-VAD-FMK (EGF V10); 4) 1 mM Z-VAD-FMK; 5) 10 mM Z-VAD-FMK and (6) no EGF and Z-VAD-FMK supplementation. Ovarian follicles within the tissues were processed for histology and assessed for follicle density, viability (based on morphology) and diameter immediately after collection (Control) or after 3 or 7 days of in vitro incubation. Comparison among fresh and culture treatment group was performed using ANOVA test. There were no differences (P > 0.05) in follicle density and viability among different culture treatments. However, there were differences in this parameter between culture days. Specifically, culturing tissue for 7 days resulted in significant reduction in follicle viability and density, regardless of treatments. We found a difference in size between culture days when these follicles were cultured using 10 mM Z-VAD-FMK or 10 ng/mL EGF (EGF V0). In sum, the finding demonstrated that Z-VAD-FMK at the dosage used in the present study does not provide the protective effect to ovarian tissue during in vitro culture. Future studies should explore different Z-VAD-FMK dosages or other anti-apoptotic agent, such as surviving in protecting ovarian follicles against cell death.

Keywords: anti apoptotic drug, bitches, follicles, Z-VAD-FMK

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2516 Econophysical Approach on Predictability of Financial Crisis: The 2001 Crisis of Turkey and Argentina Case

Authors: Arzu K. Kamberli, Tolga Ulusoy

Abstract:

Technological developments and the resulting global communication have made the 21st century when large capitals are moved from one end to the other via a button. As a result, the flow of capital inflows has accelerated, and capital inflow has brought with it crisis-related infectiousness. Considering the irrational human behavior, the financial crisis in the world under the influence of the whole world has turned into the basic problem of the countries and increased the interest of the researchers in the reasons of the crisis and the period in which they lived. Therefore, the complex nature of the financial crises and its linearly unexplained structure have also been included in the new discipline, econophysics. As it is known, although financial crises have prediction mechanisms, there is no definite information. In this context, in this study, using the concept of electric field from the electrostatic part of physics, an early econophysical approach for global financial crises was studied. The aim is to define a model that can take place before the financial crises, identify financial fragility at an earlier stage and help public and private sector members, policy makers and economists with an econophysical approach. 2001 Turkey crisis has been assessed with data from Turkish Central Bank which is covered between 1992 to 2007, and for 2001 Argentina crisis, data was taken from IMF and the Central Bank of Argentina from 1997 to 2007. As an econophysical method, an analogy is used between the Gauss's law used in the calculation of the electric field and the forecasting of the financial crisis. The concept of Φ (Financial Flux) has been adopted for the pre-warning of the crisis by taking advantage of this analogy, which is based on currency movements and money mobility. For the first time used in this study Φ (Financial Flux) calculations obtained by the formula were analyzed by Matlab software, and in this context, in 2001 Turkey and Argentina Crisis for Φ (Financial Flux) crisis of values has been confirmed to give pre-warning.

Keywords: econophysics, financial crisis, Gauss's Law, physics

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2515 Relationship between Body Mass Composition and Primary Dysmenorrhoea

Authors: Snehalata Tembhurne

Abstract:

Introduction: A healthy menstrual cycle is a sign of women’s sound health.Various variables may influence the length and regularity of menstrual cycle.Studies have revealed that menstrual cycle abnormalities may be associated with psychological stress,lack of physical exercise, alteration in body composition,endocrine disturbances,higher estrogen levels as seen in obese females.Hence there is an urgent need to find out the relationship between variations in body mass composition(BMI & body fat%) with menstrual abnormalities like primary dysmenorrhoea. Aim: To find out the relationship between body mass composition and primary dysmenorrhea. Objectives: 1.To check whether there is any association between body mass index and primary dysmenorrhoea.2.To check whether there is any association between body fat percentage and primary dysmenorrhoea. NULL HYPOTHESES-There is no relationship between body mass composition and primary dysmenorrhea. Hypothesis: There exists a relationship between body mass composition and primary dysmenorrhea. Materials and Methods: The study was conducted over a period of 6 months with 90 samples selected on random basis. The procedure was explained to the participant and a written consent was taken thereafter. The participant was made to stand on the BODY COMPOSITION SCANNING MONITOR, which scanned the physical profile of the participant (height, weight, BMI, body fat percentage and visceral fat).Thereafter, the candidate was asked about her menstrual irregularities and was asked to grade her level of dysmenorrhoea (if present) using the Verbal Dimensional Dysmenorrhea Scale. Results: Chi square test of association was used to find out the association between body mass composition(body mass index,body fat percentage) and primary dysmenorrhea.The chi-square value for association between body mass index and primary dysmenorrhea was 38.63 p<0.001 which was statistically significant.The chi-square value for the association of body fat % & primary dysmenorrhea was 30.09,p<0.001which was statistically significant. Conclusion: Study shows that there exists a significant relationship between body mass composition and primary dysmenorrhea and as the value of Body mass index and body fat percentages goes on increasing in females, the severity of primary dysmenorrhea also increases.

Keywords: body mass index, body composition screening monitor, primary dysmenorrhea, verbal dimensional dysmenorrhea scale

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2514 A Microwave and Millimeter-Wave Transmit/Receive Switch Subsystem for Communication Systems

Authors: Donghyun Lee, Cam Nguyen

Abstract:

Multi-band systems offer a great deal of benefit in modern communication and radar systems. In particular, multi-band antenna-array radar systems with their extended frequency diversity provide numerous advantages in detection, identification, locating and tracking a wide range of targets, including enhanced detection coverage, accurate target location, reduced survey time and cost, increased resolution, improved reliability and target information. An accurate calibration is a critical issue in antenna array systems. The amplitude and phase errors in multi-band and multi-polarization antenna array transceivers result in inaccurate target detection, deteriorated resolution and reduced reliability. Furthermore, the digital beam former without the RF domain phase-shifting is less immune to unfiltered interference signals, which can lead to receiver saturation in array systems. Therefore, implementing integrated front-end architecture, which can support calibration function with low insertion and filtering function from the farthest end of an array transceiver is of great interest. We report a dual K/Ka-band T/R/Calibration switch module with quasi-elliptic dual-bandpass filtering function implementing a Q-enhanced metamaterial transmission line. A unique dual-band frequency response is incorporated in the reception and calibration path of the proposed switch module utilizing the composite right/left-handed meta material transmission line coupled with a Colpitts-style negative generation circuit. The fabricated fully integrated T/R/Calibration switch module in 0.18-μm BiCMOS technology exhibits insertion loss of 4.9-12.3 dB and isolation of more than 45 dB in the reception, transmission and calibration mode of operation. In the reception and calibration mode, the dual-band frequency response centered at 24.5 and 35 GHz exhibits out-of-band rejection of more than 30 dB compared to the pass bands below 10.5 GHz and above 59.5 GHz. The rejection between the pass bands reaches more than 50 dB. In all modes of operation, the IP1-dB is between 4 and 11 dBm. Acknowledgement: This paper was made possible by NPRP grant # 6-241-2-102 from the Qatar National Research Fund (a member of Qatar Foundation). The statements made herein are solely the responsibility of the authors.

Keywords: microwaves, millimeter waves, T/R switch, wireless communications, wireless communications

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2513 Chromatographic Preparation and Performance on Zinc Ion Imprinted Monolithic Column and Its Adsorption Property

Authors: X. Han, S. Duan, C. Liu, C. Zhou, W. Zhu, L. Kong

Abstract:

The ionic imprinting technique refers to the three-dimensional rigid structure with the fixed pore sizes, which was formed by the binding interactions of ions and functional monomers and used ions as the template, it has a high level of recognition to the ionic template. The preparation of monolithic column by the in-situ polymerization need to put the compound of template, functional monomers, cross-linking agent and initiating agent into the solution, dissolve it and inject to the column tube, and then the compound will have a polymerization reaction at a certain temperature, after the synthetic reaction, we washed out the unread template and solution. The monolithic columns are easy to prepare, low consumption and cost-effective with fast mass transfer, besides, they have many chemical functions. But the monolithic columns have some problems in the practical application, such as low-efficiency, quantitative analysis cannot be performed accurately because of the peak shape is wide and has tailing phenomena; the choice of polymerization systems is limited and the lack of theoretical foundations. Thus the optimization of components and preparation methods is an important research direction. During the preparation of ionic imprinted monolithic columns, pore-forming agent can make the polymer generate the porous structure, which can influence the physical properties of polymer, what’ s more, it can directly decide the stability and selectivity of polymerization reaction. The compounds generated in the pre-polymerization reaction could directly decide the identification and screening capabilities of imprinted polymer; thus the choice of pore-forming agent is quite critical in the preparation of imprinted monolithic columns. This article mainly focuses on the research that when using different pore-forming agents, the impact of zinc ion imprinted monolithic column on the enrichment performance of zinc ion.

Keywords: high performance liquid chromatography (HPLC), ionic imprinting, monolithic column, pore-forming agent

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2512 Examining the Role of Brand Equity and Explore the Influence of Consumers' Brand Relationship Quality

Authors: Jim Shih-Chiao Chin , Tsai Lin Hsu, Shui Lien Chen

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This article extends the relation between company’s employee and customers in market. According to the previous researches, most researchers analyzed and focused on customers’ brand perception. In the recently, some scholars star to explore the brand management from company viewpoint. The aim of this study is to explore whether consumers perception would be affected by the firm brand. This research would like to examine the relationship between individual consumers and corporate brands in the business-to-consumers sector. First, the study develops a framework that the connection with consumer and company. Second, this article uses three dimensions, brand knowledge, brand commitment, and brand equity to measure employees’ loyalty of brand and applies brand relationship quality to gauge the level of brand’s importance in consumer’s mind. This paper uses SPSS 20.0 and AMOS 20.0 to test consumers’ minds toward the brand equity which the company provides. There are totally 862 valid questionnaires returned, and 431 participants are consumers; the other 431 participants are employees. Those questionnaires are one-by-one to consumer and employee so those are 431 pairs questionnaires. Based on 431 pairs of consumers and company’s employees, analyzed results show that brand knowledge and brand commitment play important roles influencing brand equity. The results also demonstrate the extra-role brand equity positively impact on the brand relationship quality of consumers. In addition, the findings reveal that the company can improve brand relationship quality of consumers by enhancing extra-role brand equity. There is a sufficient evidence denote that brand relationship quality not only shows about the brand of customers’ thought but also implies company how to build the brand to impress on consumers. These findings provide the degree of the brand in consumers’ cognition. The brand-owner employee can reference the conclusion to creative new strategic to the next time or can be one of the company’s competitive advantages. Those results and conclusions are contributed to management practice and future.

Keywords: brand knowledge, brand commitment, brand equity, brand relationship quality

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2511 The Influence of the Aquatic Environment on Hematological Parameters in Cyprinus carpio

Authors: Andreea D. Șerban, Răzvan Mălăncuș, Mihaela Ivancia, Șteofil Creangă

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Just as air influences the quality of life in the terrestrial environment, water, as a living environment, is one of great importance when it comes to the quality of life of underwater animals, which acquires an even higher degree of importance when analyzing underwater creatures as future products for human consumption. Thus, going beyond the ideal environment, in which all water quality parameters are permanently in perfect standards for reproduction, growth, and development of fish material and customizing this study to reality, it was demonstrated the importance of reproduction, development, and growth of biological material, necessary in the population fish farms, in the same environment to gain the maximum yield that a fish farm can offer. The biological material used was harvested from 3 fish farms located at great distances from each other to have environments with different parameters. The specimens were clinically healthy at 2 years of age. Thus, the differences in water quality parameters had effects on specimens from other environments, describing large curves in their evolution in new environments. Another change was observed in the new environment, the specimens contributing with the "genetic package" to its modification, tending to a balance of the parameters studied to the values in the environment in which they lived until the time of the experiment. The study clearly showed that adaptability to the environment in which an individual has developed and grown is not valid in environments with different parameters, resulting even in the fatality of one sample during the experiment. In some specimens, the values of the studied hematological parameters were halved after the transfer to the new environment, and in others, the same parameters were doubled. The study concludes that the specimens were adapted to the environment in which they developed and grew, their descendants having a higher value of heritability only in the initial environment. It is known that heritability is influenced 50% by the genetic package of the individual and 50% by the environment, by removing the value of the environment, the duration of improvement of characters of interest will be shorter and the maximum yield of fish farms can be achieved in a smaller period.

Keywords: environment, heritability, quality, water

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2510 “It Plays a Huge Role”: Examining Dual Language Teachers’ Conceptions of Language, Culture and Sociocultural Competence

Authors: Giselle Martinez Negrette

Abstract:

Language and culture mutually shape and reflect the human experience. In the learning process, this connection creates and sustains the shared world of learners and educators. Dual Language (DL) programs exemplify this relationship by placing language and culture at the center of their educational approach. These programs, originally conceived to advance social justice in education, aim to foster bilingualism, biliteracy, academic development and sociocultural competence, emphasizing the inseparability of linguistic and cultural growth. Furthermore, because DL programs serve children from diverse cultural, ethnic, and socioeconomic backgrounds, they operate as spaces where linguistic skills and sociocultural understandings are actively cultivated, negotiated, and celebrated. Against this background, this paper examines how two DL teachers see language and culture shaping and reflecting the educational experience, and how their understandings of the relationship influence their mediation of sociocultural competence in their classrooms. This qualitative study employs critical discourse analysis to study in detail participants’ narratives seeking to uncover their perspectives on the “politics” surrounding language use and cultural understandings in their school contexts. Our findings show that these educators are not only keenly aware of the pivotal role that language and culture play in multilingual students’ learning journeys, but they have identified the sociolinguistic “games” taking place in their classrooms. We contend these understandings are pivotal for the critical development of sociocultural competence in DL programs. This study provides DL educators with important conceptual and pedagogical insights regarding the intersection between language and culture in their classrooms and seeks to encourage them to analyze their roles as supporters or opponents of transformative rupture opportunities to contest inequities in education

Keywords: sociocultural competence, critical discourse analysis, dual language programs, language, culture

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2509 Establishment and Validation of Correlation Equations to Estimate Volumetric Oxygen Mass Transfer Coefficient (KLa) from Process Parameters in Stirred-Tank Bioreactors Using Response Surface Methodology

Authors: Jantakan Jullawateelert, Korakod Haonoo, Sutipong Sananseang, Sarun Torpaiboon, Thanunthon Bowornsakulwong, Lalintip Hocharoen

Abstract:

Process scale-up is essential for the biological process to increase production capacity from bench-scale bioreactors to either pilot or commercial production. Scale-up based on constant volumetric oxygen mass transfer coefficient (KLa) is mostly used as a scale-up factor since oxygen supply is one of the key limiting factors for cell growth. However, to estimate KLa of culture vessels operated with different conditions are time-consuming since it is considerably influenced by a lot of factors. To overcome the issue, this study aimed to establish correlation equations of KLa and operating parameters in 0.5 L and 5 L bioreactor employed with pitched-blade impeller and gas sparger. Temperature, gas flow rate, agitation speed, and impeller position were selected as process parameters and equations were created using response surface methodology (RSM) based on central composite design (CCD). In addition, the effects of these parameters on KLa were also investigated. Based on RSM, second-order polynomial models for 0.5 L and 5 L bioreactor were obtained with an acceptable determination coefficient (R²) as 0.9736 and 0.9190, respectively. These models were validated, and experimental values showed differences less than 10% from the predicted values. Moreover, RSM revealed that gas flow rate is the most significant parameter while temperature and agitation speed were also found to greatly affect the KLa in both bioreactors. Nevertheless, impeller position was shown to influence KLa in only 5L system. To sum up, these modeled correlations can be used to accurately predict KLa within the specified range of process parameters of two different sizes of bioreactors for further scale-up application.

Keywords: response surface methodology, scale-up, stirred-tank bioreactor, volumetric oxygen mass transfer coefficient

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2508 Design and Development of a Mechanical Force Gauge for the Square Watermelon Mold

Authors: Morteza Malek Yarand, Hadi Saebi Monfared

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This study aimed at designing and developing a mechanical force gauge for the square watermelon mold for the first time. It also tried to introduce the square watermelon characteristics and its production limitations. The mechanical force gauge performance and the product itself were also described. There are three main designable gauge models: a. hydraulic gauge, b. strain gauge, and c. mechanical gauge. The advantage of the hydraulic model is that it instantly displays the pressure and thus the force exerted by the melon. However, considering the inability to measure forces at all directions, complicated development, high cost, possible hydraulic fluid leak into the fruit chamber and the possible influence of increased ambient temperature on the fluid pressure, the development of this gauge was overruled. The second choice was to calculate pressure using the direct force a strain gauge. The main advantage of these strain gauges over spring types is their high precision in measurements; but with regard to the lack of conformity of strain gauge working range with water melon growth, calculations were faced with problems. Finally the mechanical pressure gauge has advantages, including the ability to measured forces and pressures on the mold surface during melon growth; the ability to display the peak forces; the ability to produce melon growth graph thanks to its continuous force measurements; the conformity of its manufacturing materials with the required physical conditions of melon growth; high air conditioning capability; the ability to permit sunlight reaches the melon rind (no yellowish skin and quality loss); fast and straightforward calibration; no damages to the product during assembling and disassembling; visual check capability of the product within the mold; applicable to all growth environments (field, greenhouses, etc.); simple process; low costs and so forth.

Keywords: mechanical force gauge, mold, reshaped fruit, square watermelon

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2507 Overcoming Mistrusted Masculinity: Analyzing Muslim Men and Their Aspirations for Fatherhood in Denmark

Authors: Anne Hovgaard Jorgensen

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This study investigates how Muslim fathers in Denmark are struggling to overcome notions of mistrust from teachers and educators. Starting from school-home-cooperation (parent conferences, school-home communication, etc.), the study finds that many Muslim fathers do not feel acknowledged as a resource in the upbringing of their children. To explain these experiences further, the study suggest the notion of ‘mistrusted masculinity’ to grasp the controlling image these fathers meet in various schools and child-care-institutions in the Danish Welfare state. The paper is based on 9 months of fieldwork in a Danish school, a social housing area and in various ‘father groups’ in Denmark. Additional, 50 interviews were conducted with fathers, children, mothers, schoolteachers, and educators. By using Connell's concepts 'hegemonic' and 'marginalized' masculinity as steppingstones, the paper argues that these concepts might entail a too static and dualistic picture of gender. By applying the concepts of 'emergent masculinity' and 'emergent fatherhood' the paper brings along a long needed discussion of how Muslim men in Denmark are struggling to overcome and change the controlling images of them as patriarchal and/or ignorant fathers regarding the upbringing of their children. As such, the paper shows how Muslim fathers are taking action to change this controlling image, e.g. through various ‘father groups’. The paper is inspired by the phenomenological notions of ‘experience´ and in the light of this notion, the paper tells the fathers’ stories about their upbringing of their children and aspirations for fatherhood. These stories share light on how these fathers take care of their children in everyday life. The study also shows that the controlling image of these fathers have affected how some Muslim fathers are actually being fathers. The study shows that fear of family-interventions from teachers or social workers e.g. have left some Muslim fathers in a limbo, being afraid of scolding their children, and being confused of ‘what good parenting in Denmark is’. This seems to have led to a more lassie fair upbringing than these fathers actually wanted. This study is important since anthropologists generally have underexposed the notion of fatherhood, and how fathers engage in the upbringing of their children. Over more, the vast majority of qualitative studies of fatherhood have been on white middleclass fathers, living in nuclear families. In addition, this study is crucial at this very moment due to the major refugee crisis in Denmark and in the Western world in general. A crisis, which has resulted in a vast number of scare campaigns against Islam from different nationalistic political parties, which enforces the negative controlling image of Muslim fathers.

Keywords: fatherhood, Muslim fathers, mistrust, education

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2506 Roundabout Implementation Analyses Based on Traffic Microsimulation Model

Authors: Sanja Šurdonja, Aleksandra Deluka-Tibljaš, Mirna Klobučar, Irena Ištoka Otković

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Roundabouts are a common choice in the case of reconstruction of an intersection, whether it is to improve the capacity of the intersection or traffic safety, especially in urban conditions. The regulation for the design of roundabouts is often related to driving culture, the tradition of using this type of intersection, etc. Individual values in the regulation are usually recommended in a wide range (this is the case in Croatian regulation), and the final design of a roundabout largely depends on the designer's experience and his/her choice of design elements. Therefore, before-after analyses are a good way to monitor the performance of roundabouts and possibly improve the recommendations of the regulation. This paper presents a comprehensive before-after analysis of a roundabout on the country road network near Rijeka, Croatia. The analysis is based on a thorough collection of traffic data (operating speeds and traffic load) and design elements data, both before and after the reconstruction into a roundabout. At the chosen location, the roundabout solution aimed to improve capacity and traffic safety. Therefore, the paper analyzed the collected data to see if the roundabout achieved the expected effect. A traffic microsimulation model (VISSIM) of the roundabout was created based on the real collected data, and the influence of the increase of traffic load and different traffic structures, as well as of the selected design elements on the capacity of the roundabout, were analyzed. Also, through the analysis of operating speeds and potential conflicts by application of the Surrogate Safety Assessment Model (SSAM), the traffic safety effect of the roundabout was analyzed. The results of this research show the practical value of before-after analysis as an indicator of roundabout effectiveness at a specific location. The application of a microsimulation model provides a practical method for analyzing intersection functionality from a capacity and safety perspective in present and changed traffic and design conditions.

Keywords: before-after analysis, operating speed, capacity, design.

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2505 Productivity, Phenolic Composition and Antioxidant Activity of Arrowroot (Maranta arundinacea)

Authors: Maira C. M. Fonseca, Maria Aparecida N. Sediyama, Rosana Goncalves R. das Dores, Sanzio Mollica Vidigal, Alberto C. P. Dias

Abstract:

Among Brazilian plant diversity, many species are used as food and considered minor crops (non-conventional plant foods) (NCPF). Arrowroot (Maranta arundinacea) is a NCPF from which starch is extracted from rhizome do not have gluten. Thus, arrowroot flower starch can be consumed by celiac people. Additional, some medicinal and functional proprieties are assigned to arrowroot leaves which currently are underutilized. In Brazil, it’s cultivated mainly by small scale farmers and there is no specific recommendation for fertilization. This work aimed to determinate the best fertilization for rhizome production and to verify its influence in phenolic composition and antioxidant activity of leaf extracts. Two arrowroot varieties, “Common” and “Seta”, were cultivated in organic system at state of Minas Gerais, Brazil, using cattle manure with three levels of nitrogen (N) (0, 300 and 900 kg N ha-1). The experiment design was in randomized block with four replicates. The highest production of rhizomes in both varieties, “Common” (38198.24 kg ha-1) and “Seta” (43567.71 kg ha-1), were obtained with the use of 300 kg N ha-1. With this fertilization, the total aerial part, petiole and leaf production in the varieties were respectively: “Common” (190.312 kg ha-1; 159.312 kg ha-1; 31.100 kg ha-1) and “Seta” (207.656 kg ha-1; 180.539 kg ha-1; 27.062 kg ha-1). Methanolic leaf extracts were analysed by HPLC-DAD. The major phenolic compounds found were caffeioylquinic acids, p-coumaric derivatives and flavonoids. In general, the production of these compounds significantly decreases with the increase levels of nitrogen (900 kg N ha-1). With 300 kg N ha-1 the phenolic production was similar to control. The antioxidant activity was evaluated using DPPH method and was detected around 60% of radical scavenging when 0.1 mg/mL of plant extracts were used. We concluded that fertilization with 300 kg N ha-1 increased arrowroot rhizome production, maintaining phenolic compounds yield at leaves.

Keywords: antioxidant activity, non-conventional plants, organic fertilization, phenolic compounds

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2504 Adhesive Bonded Joints Characterization and Crack Propagation in Composite Materials under Cyclic Impact Fatigue and Constant Amplitude Fatigue Loadings

Authors: Andres Bautista, Alicia Porras, Juan P. Casas, Maribel Silva

Abstract:

The Colombian aeronautical industry has stimulated research in the mechanical behavior of materials under different loading conditions aircrafts are generally exposed during its operation. The Calima T-90 is the first military aircraft built in the country, used for primary flight training of Colombian Air Force Pilots, therefore, it may be exposed to adverse operating situations such as hard landings which cause impact loads on the aircraft that might produce the impact fatigue phenomenon. The Calima T-90 structure is mainly manufactured by composites materials generating assemblies and subassemblies of different components of it. The main method of bonding these components is by using adhesive joints. Each type of adhesive bond must be studied on its own since its performance depends on the conditions of the manufacturing process and operating characteristics. This study aims to characterize the typical adhesive joints of the aircraft under usual loads. To this purpose, the evaluation of the effect of adhesive thickness on the mechanical performance of the joint under quasi-static loading conditions, constant amplitude fatigue and cyclic impact fatigue using single lap-joint specimens will be performed. Additionally, using a double cantilever beam specimen, the influence of the thickness of the adhesive on the crack growth rate for mode I delamination failure, as a function of the critical energy release rate will be determined. Finally, an analysis of the fracture surface of the test specimens considering the mechanical interaction between the substrate (composite) and the adhesive, provide insights into the magnitude of the damage, the type of failure mechanism that occurs and its correlation with the way crack propagates under the proposed loading conditions.

Keywords: adhesive, composites, crack propagation, fatigue

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2503 Zimbabwe's Foreign Policy in Southern Africa, 1980-2013

Authors: Dylan Yanano Mangani, Theodore Nkadimeng Mahosi

Abstract:

Soon after independence on 18th April 1980, Zimbabwe’s foreign policy was shaped by the realities on the ground, which saw the country managing a sound relationship with both the Capitalist West and the Communist Eastern blocs. The post-independence foreign policy was therefore premised on security concerns illuminated by the Cold War era. This was one the reasons President Robert Mugabe adopted a policy of reconciliation and this earned his government recognition on the international platform. However, in Southern Africa apartheid South Africa was still the vanguard of capitalism and oppression such that she posed a serious threat to the newly born Zimbabwean nation which necessitated that Zimbabwe position herself both in the region and the continent to counter potential internal stability from within. Irrespective of how the international community viewed the country’s foreign policy Zimbabwe has continued to influence regional, continental and world geo-politics, especially on behalf of the developing nations. This raises a question why as a result of its foreign policy the country is now regarded a pariah state, especially some Western countries which used to applaud its political economic policies immediately after independence. Therefore, this study argues that the political economy of Zimbabwe had a far-reaching bearing on its foreign policy. For this reason, the problem necessitates the investigation of Zimbabwe’s foreign policy perspectives in Southern Africa since the turn of the 1990s. Two main theories which are Realism, Afro-centrism inform the study as an attempt to understand Zimbabwe’s foreign policy paradigm shift and perhaps provide answers to the objectives raised. The research therefore employs a qualitative approach where the conceptual nature of the study into the foreign policy of Zimbabwe is largely desktop research. However, the nature of the study will also require that oral interviews are conducted to substantiate some of the arguments advanced.

Keywords: cold war set up, foreign policy, look east policy, pan-africanism, post 2000 period, Southern Africa, Zimbabwe

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2502 Internet Memes as Meaning-Making Tools within Subcultures: A Case Study of Lolita Fashion

Authors: Victoria Esteves

Abstract:

Online memes have not only impacted different aspects of culture, but they have also left their mark on particular subcultures, where memes have reflected issues and debates surrounding specific spheres of interest. This is the first study that outlines how memes can address cultural intersections within the Lolita fashion community, which are much more specific and which fall outside of the broad focus of politics and/or social commentary. This is done by looking at the way online memes are used in this particular subculture as a form of meaning-making and group identity reinforcement, demonstrating not only the adaptability of online memes to specific cultural groups but also how subcultures tailor these digital objects to discuss both community-centered topics and more broad societal aspects. As part of an online ethnography, this study focuses on qualitative content analysis by taking a look at some of the meme communication that has permeated Lolita fashion communities. Examples of memes used in this context are picked apart in order to understand this specific layered phenomenon of communication, as well as to gain insights into how memes can operate as visual shorthand for the remix of meaning-making. There are existing parallels between internet culture and cultural behaviors surrounding Lolita fashion: not only is the latter strongly influenced by the former (due to its highly globalized dispersion and lack of physical shops, Lolita fashion is almost entirely reliant on the internet for its existence), both also emphasize curatorial roles through a careful collaborative process of documenting significant aspects of their culture (e.g., Know Your Meme and Lolibrary). Further similarities appear when looking at ideas of inclusion and exclusion that permeate both cultures, where memes and language are used in order to both solidify group identity and to police those who do not ascribe to these cultural tropes correctly, creating a feedback loop that reinforces subcultural ideals. Memes function as excellent forms of communication within the Lolita community because they reinforce its coded ideas and allows a kind of participation that echoes other cultural groups that are online-heavy such as fandoms. Furthermore, whilst the international Lolita community was mostly self-contained within its LiveJournal birthplace, it has become increasingly dispersed through an array of different social media groups that have fragmented this subculture significantly. The use of memes is key in maintaining a sense of connection throughout this now fragmentary experience of fashion. Memes are also used in the Lolita fashion community to bridge the gap between Lolita fashion related community issues and wider global topics; these reflect not only an ability to make use of a broader online language to address specific issues of the community (which in turn provide a very community-specific engagement with remix practices) but also memes’ ability to be tailored to accommodate overlapping cultural and political concerns and discussions between subcultures and broader societal groups. Ultimately, online memes provide the necessary elasticity to allow their adaption and adoption by subcultural groups, who in turn use memes to extend their meaning-making processes.

Keywords: internet culture, Lolita fashion, memes, online community, remix

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2501 One-Dimensional Numerical Simulation of the Nonlinear Instability Behavior of an Electrified Viscoelastic Liquid Jet

Authors: Fang Li, Xie-Yuan Yin, Xie-Zhen Yin

Abstract:

Instability and breakup of electrified viscoelastic liquid jets are involved in various applications such as inkjet printing, fuel atomization, the pharmaceutical industry, electrospraying, and electrospinning. Studying on the instability of electrified viscoelastic liquid jets is of theoretical and practical significance. We built a one-dimensional electrified viscoelastic model to study the nonlinear instability behavior of a perfecting conducting, slightly viscoelastic liquid jet under a radial electric field. The model is solved numerically by using an implicit finite difference scheme together with a boundary element method. It is found that under a radial electric field a viscoelastic liquid jet still evolves into a beads-on-string structure with a thin filament connecting two adjacent droplets as in the absence of an electric field. A radial electric field exhibits limited influence on the decay of the filament thickness in the nonlinear evolution process of a viscoelastic jet, in contrast to its great enhancing effect on the linear instability of the jet. On the other hand, a radial electric field can induce axial non-uniformity of the first normal stress difference within the filament. Particularly, the magnitude of the first normal stress difference near the midpoint of the filament can be greatly decreased by a radial electric field. Decreasing the extensional stress by a radial electric field may found applications in spraying, spinning, liquid bridges and others. In addition, the effect of a radial electric field on the formation of satellite droplets is investigated on the parametric plane of the dimensionless wave number and the electrical Bond number. It is found that satellite droplets may be formed for a larger axial wave number at a larger radial electric field. The present study helps us gain insight into the nonlinear instability characteristics of electrified viscoelastic liquid jets.

Keywords: non linear instability, one-dimensional models, radial electric fields, viscoelastic liquid jets

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2500 Recent Progress in the Uncooled Mid-Infrared Lead Selenide Polycrystalline Photodetector

Authors: Hao Yang, Lei Chen, Ting Mei, Jianbang Zheng

Abstract:

Currently, the uncooled PbSe photodetectors in the mid-infrared range (2-5μm) with sensitization technology extract more photoelectric response than traditional ones, and enable the room temperature (300K) photo-detection with high detectivity, which have attracted wide attentions in many fields. This technology generally contains the film fabrication with vapor phase deposition (VPD) and a sensitizing process with doping of oxygen and iodine. Many works presented in the recent years almost provide and high temperature activation method with oxygen/iodine vapor diffusion, which reveals that oxygen or iodine plays an important role in the sensitization of PbSe material. In this paper, we provide our latest experimental results and discussions in the stoichiometry of oxygen and iodine and its influence on the polycrystalline structure and photo-response. The experimental results revealed that crystal orientation was transformed from (200) to (420) by sensitization, and the responsivity of 5.42 A/W was gained by the optimal stoichiometry of oxygen and iodine with molecular density of I2 of ~1.51×1012 mm-3 and oxygen pressure of ~1Mpa. We verified that I2 plays a role in transporting oxygen into the lattice of crystal, which is actually not its major role. It is revealed that samples sensitized with iodine transform atomic proportion of Pb from 34.5% to 25.0% compared with samples without iodine from XPS data, which result in the proportion of about 1:1 between Pb and Se atoms by sublimation of PbI2 during sensitization process, and Pb/Se atomic proportion is controlled by I/O atomic proportion in the polycrystalline grains, which is very an important factor for improving responsivity of uncooled PbSe photodetector. Moreover, a novel sensitization and dopant activation method is proposed using oxygen ion implantation with low ion energy of < 500eV and beam current of ~120μA/cm2. These results may be helpful to understanding the sensitization mechanism of polycrystalline lead salt materials.

Keywords: polycrystalline PbSe, sensitization, transport, stoichiometry

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2499 Quantification and Detection of Non-Sewer Water Infiltration and Inflow in Urban Sewer Systems

Authors: M. Beheshti, S. Saegrov, T. M. Muthanna

Abstract:

Separated sewer systems are designed to transfer the wastewater from houses and industrial sections to wastewater treatment plants. Unwanted water in the sewer systems is a well-known problem, i.e. storm-water inflow is around 50% of the foul sewer, and groundwater infiltration to the sewer system can exceed 50% of total wastewater volume in deteriorated networks. Infiltration and inflow of non-sewer water (I/I) into sewer systems is unfavorable in separated sewer systems and can trigger overloading the system and reducing the efficiency of wastewater treatment plants. Moreover, I/I has negative economic, environmental, and social impacts on urban areas. Therefore, for having sustainable management of urban sewer systems, I/I of unwanted water into the urban sewer systems should be considered carefully and maintenance and rehabilitation plan should be implemented on these water infrastructural assets. This study presents a methodology to identify and quantify the level of I/I into the sewer system. Amount of I/I is evaluated by accurate flow measurement in separated sewer systems for specified isolated catchments in Trondheim city (Norway). Advanced information about the characteristics of I/I is gained by CCTV inspection of sewer pipelines with high I/I contribution. Achieving enhanced knowledge about the detection and localization of non-sewer water in foul sewer system during the wet and dry weather conditions will enable the possibility for finding the problem of sewer system and prioritizing them and taking decisions for rehabilitation and renewal planning in the long-term. Furthermore, preventive measures and optimization of sewer systems functionality and efficiency can be executed by maintenance of sewer system. In this way, the exploitation of sewer system can be improved by maintenance and rehabilitation of existing pipelines in a sustainable way by more practical cost-effective and environmental friendly way. This study is conducted on specified catchments with different properties in Trondheim city. Risvollan catchment is one of these catchments with a measuring station to investigate hydrological parameters through the year, which also has a good database. For assessing the infiltration in a separated sewer system, applying the flow rate measurement method can be utilized in obtaining a general view of the network condition from infiltration point of view. This study discusses commonly used and advanced methods of localizing and quantifying I/I in sewer systems. A combination of these methods give sewer operators the possibility to compare different techniques and obtain reliable and accurate I/I data which is vital for long-term rehabilitation plans.

Keywords: flow rate measurement, infiltration and inflow (I/I), non-sewer water, separated sewer systems, sustainable management

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2498 The Impact of Land Cover Change on Stream Discharges and Water Resources in Luvuvhu River Catchment, Vhembe District, Limpopo Province, South Africa

Authors: P. M. Kundu, L. R. Singo, J. O. Odiyo

Abstract:

Luvuvhu River catchment in South Africa experiences floods resulting from heavy rainfall of intensities exceeding 15 mm per hour associated with the Inter-tropical Convergence Zone (ITCZ). The generation of runoff is triggered by the rainfall intensity and soil moisture status. In this study, remote sensing and GIS techniques were used to analyze the hydrologic response to land cover changes. Runoff was calculated as a product of the net precipitation and a curve number coefficient. It was then routed using the Muskingum-Cunge method using a diffusive wave transfer model that enabled the calculation of response functions between start and end point. Flood frequency analysis was determined using theoretical probability distributions. Spatial data on land cover was obtained from multi-temporal Landsat images while data on rainfall, soil type, runoff and stream discharges was obtained by direct measurements in the field and from the Department of Water. A digital elevation model was generated from contour maps available at http://www.ngi.gov.za. The results showed that land cover changes had impacted negatively to the hydrology of the catchment. Peak discharges in the whole catchment were noted to have increased by at least 17% over the period while flood volumes were noted to have increased by at least 11% over the same period. The flood time to peak indicated a decreasing trend, in the range of 0.5 to 1 hour within the years. The synergism between remotely sensed digital data and GIS for land surface analysis and modeling was realized, and it was therefore concluded that hydrologic modeling has potential for determining the influence of changes in land cover on the hydrologic response of the catchment.

Keywords: catchment, digital elevation model, hydrological model, routing, runoff

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2497 A Literature Review on the Effect of Industrial Clusters and the Absorptive Capacity on Innovation

Authors: Enrique Claver Cortés, Bartolomé Marco Lajara, Eduardo Sánchez García, Pedro Seva Larrosa, Encarnación Manresa Marhuenda, Lorena Ruiz Fernández, Esther Poveda Pareja

Abstract:

In recent decades, the analysis of the effects of clustering as an essential factor for the development of innovations and the competitiveness of enterprises has raised great interest in different areas. Nowadays, companies have access to almost all tangible and intangible resources located and/or developed in any country in the world. However, despite the obvious advantages that this situation entails for companies, their geographical location has shown itself, increasingly clearly, to be a fundamental factor that positively influences their innovative performance and competitiveness. Industrial clusters could represent a unique level of analysis, positioned between the individual company and the industry, which makes them an ideal unit of analysis to determine the effects derived from company membership of a cluster. Also, the absorptive capacity (hereinafter 'AC') can mediate the process of innovation development by companies located in a cluster. The transformation and exploitation of knowledge could have a mediating effect between knowledge acquisition and innovative performance. The main objective of this work is to determine the key factors that affect the degree of generation and use of knowledge from the environment by companies and, consequently, their innovative performance and competitiveness. The elements analyzed are the companies' membership of a cluster and the AC. To this end, 30 most relevant papers published on this subject in the "Web of Science" database have been reviewed. Our findings show that, within a cluster, the knowledge coming from the companies' environment can significantly influence their innovative performance and competitiveness, although in this relationship, the degree of access and exploitation of the companies to this knowledge plays a fundamental role, which depends on a series of elements both internal and external to the company.

Keywords: absorptive capacity, clusters, innovation, knowledge

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2496 Exploring the Concerns and Practices Associated with Organ Transplantation in the Context of Muslims in Pakistan from an Anthropological Perspective

Authors: Qurratulain Faheem

Abstract:

The human body often serves as a reference point to analyse the notions of self and society. Situating on Merleau-Ponty and Bourdieu theories of embodiments, this research explores the notions around the human body and its influence on the ethical considerations in regards to organ transplantation among the Muslim communities in Pakistan. The context of Pakistan makes an intriguing case study as cadaveric organ transplantation is not in practise. Whereas living organ transplantation is commonly is practised between family members only. These contradictory practices apparently rests on the ideologies around the human body and religious beliefs as well the personal judgements and authority of healthcare professionals. This research is a year-long ethnographic study carried out as part of doctoral studies. An anthropological approach towards organ transplantation in Pakistan brought forward various socio-cultural notions around the human body and selfhood that serve as a framework around biomedical ethical issues in various societies. Further, it surface the contradictions and issues associated with organ transplantation that makes it a dilemma situated in a nexus of various socio-cultural and political factors rather seeing it as an isolated health concern. This research is a novel study on the subject of organ transplantation in the context of Pakistan but also put forward ethnographic data that could serve as a reference in other religious societies. Further, the ethnographic data bring forward experiences and stories of organ receivers, organ donors, religious leaders, healthcare professionals, and the general public, which aspire to encourage biomedical ethicists and social-scientists to consider ethnography as a research methodology and rely upon people’s lived experiences while establishing policies and practices around biomedical ethical issues.

Keywords: Gender, organ transplantation, muslims, pakistan, organ donation, bioethics, culture and religion, gender

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2495 Regeneration of Cesium-Exhausted Activated Carbons by Microwave Irradiation

Authors: Pietro P. Falciglia, Erica Gagliano, Vincenza Brancato, Alfio Catalfo, Guglielmo Finocchiaro, Guido De Guidi, Stefano Romano, Paolo Roccaro, Federico G. A. Vagliasindi

Abstract:

Cesium-137 (¹³⁷Cs) is a major radionuclide in spent nuclear fuel processing, and it represents the most important cause of contamination related to nuclear accidents. Cesium-137 has long-term radiological effects representing a major concern for the human health. Several physico-chemical methods have been proposed for ¹³⁷Cs removal from impacted water: ion-exchange, adsorption, chemical precipitation, membrane process, coagulation, and electrochemical. However, these methods can be limited by ionic selectivity and efficiency, or they present very restricted full-scale application due to equipment and chemical high costs. On the other hand, adsorption is considered a more cost-effective solution, and activated carbons (ACs) are known as a low-cost and effective adsorbent for a wide range of pollutants among which radionuclides. However, adsorption of Cs onto ACs has been investigated in very few and not exhaustive studies. In addition, exhausted activated carbons are generally discarded in landfill, that is not an eco-friendly and economic solution. Consequently, the regeneration of exhausted ACs must be considered a preferable choice. Several alternatives, including conventional thermal-, solvent-, biological- and electrochemical-regeneration, are available but are affected by several economic or environmental concerns. Microwave (MW) irradiation has been widely used in industrial and environmental applications and it has attracted many attentions to regenerating activated carbons. The growing interest in MW irradiation is based on the passive ability of the irradiated medium to convert a low power irradiation energy into a rapid and large temperature increase if the media presents good dielectric features. ACs are excellent MW-absorbers, with a high mechanical strength and a good resistance towards heating process. This work investigates the feasibility of MW irradiation for the regeneration of Cs-exhausted ACs. Adsorption batch experiments were carried out using commercially available granular activated carbon (GAC), then Cs-saturated AC samples were treated using a controllable bench-scale 2.45-GHz MW oven and investigating different adsorption-regeneration cycles. The regeneration efficiency (RE), weight loss percentage, and textural properties of the AC samples during the adsorption-regeneration cycles were also assessed. Main results demonstrated a relatively low adsorption capacity for Cs, although the feasibility of ACs was strictly linked to their dielectric nature, which allows a very efficient thermal regeneration by MW irradiation. The weight loss percentage was found less than 2%, and an increase in RE after three cycles was also observed. Furthermore, MW regeneration preserved the pore structure of the regenerated ACs. For a deeper exploration of the full-scale applicability of MW regeneration, further investigations on more adsorption-regeneration cycles or using fixed-bed columns are required.

Keywords: adsorption mechanisms, cesium, granular activated carbons, microwave regeneration

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2494 Characterization of Dota-Girentuximab Conjugates for Radioimmunotherapy

Authors: Tais Basaco, Stefanie Pektor, Josue A. Moreno, Matthias Miederer, Andreas Türler

Abstract:

Radiopharmaceuticals based in monoclonal anti-body (mAb) via chemical linkers have become a potential tool in nuclear medicine because of their specificity and the large variability and availability of therapeutic radiometals. It is important to identify the conjugation sites and number of attached chelator to mAb to obtain radioimmunoconjugates with required immunoreactivity and radiostability. Girentuximab antibody (G250) is a potential candidate for radioimmunotherapy of clear cell carcinomas (RCCs) because it is reactive with CAIX antigen, a transmembrane glycoprotein overexpressed on the cell surface of most ( > 90%) (RCCs). G250 was conjugated with the bifunctional chelating agent DOTA (1,4,7,10-Tetraazacyclododecane-N,N’,N’’,N’’’-tetraacetic acid) via a benzyl-thiocyano group as a linker (p-SCN-Bn-DOTA). DOTA-G250 conjugates were analyzed by size exclusion chromatography (SE-HPLC) and by electrophoresis (SDS-PAGE). The potential site-specific conjugation was identified by liquid chromatography–mass spectrometry (LC/MS-MS) and the number of linkers per molecule of mAb was calculated using the molecular weight (MW) measured by matrix assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS). The average number obtained in the conjugates in non-reduced conditions was between 8-10 molecules of DOTA per molecule of mAb. The average number obtained in the conjugates in reduced conditions was between 1-2 and 3-4 molecules of DOTA per molecule of mAb in the light chain (LC) and heavy chain (HC) respectively. Potential DOTA modification sites of the chelator were identified in lysine residues. The biological activity of the conjugates was evaluated by flow cytometry (FACS) using CAIX negative (SKRC-18) and CAIX positive (SKRC-52). The DOTA-G250 conjugates were labelled with 177Lu with a radiochemical yield > 95% reaching specific activities of 12 MBq/µg. The stability in vitro of different types of radioconstructs was analyzed in human serum albumin (HSA). The radiostability of 177Lu-DOTA-G250 at high specific activity was increased by addition of sodium ascorbate after the labelling. The immunoreactivity was evaluated in vitro and in vivo. Binding to CAIX positive cells (SK-RC-52) at different specific activities was higher for conjugates with less DOTA content. Protein dose was optimized in mice with subcutaneously growing SK-RC-52 tumors using different amounts of 177Lu- DOTA-G250.

Keywords: mass spectrometry, monoclonal antibody, radiopharmaceuticals, radioimmunotheray, renal cancer

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2493 Modeling of Bipolar Charge Transport through Nanocomposite Films for Energy Storage

Authors: Meng H. Lean, Wei-Ping L. Chu

Abstract:

The effects of ferroelectric nanofiller size, shape, loading, and polarization, on bipolar charge injection, transport, and recombination through amorphous and semicrystalline polymers are studied. A 3D particle-in-cell model extends the classical electrical double layer representation to treat ferroelectric nanoparticles. Metal-polymer charge injection assumes Schottky emission and Fowler-Nordheim tunneling, migration through field-dependent Poole-Frenkel mobility, and recombination with Monte Carlo selection based on collision probability. A boundary integral equation method is used for solution of the Poisson equation coupled with a second-order predictor-corrector scheme for robust time integration of the equations of motion. The stability criterion of the explicit algorithm conforms to the Courant-Friedrichs-Levy limit. Trajectories for charge that make it through the film are curvilinear paths that meander through the interspaces. Results indicate that charge transport behavior depends on nanoparticle polarization with anti-parallel orientation showing the highest leakage conduction and lowest level of charge trapping in the interaction zone. Simulation prediction of a size range of 80 to 100 nm to minimize attachment and maximize conduction is validated by theory. Attached charge fractions go from 2.2% to 97% as nanofiller size is decreased from 150 nm to 60 nm. Computed conductivity of 0.4 x 1014 S/cm is in agreement with published data for plastics. Charge attachment is increased with spheroids due to the increase in surface area, and especially so for oblate spheroids showing the influence of larger cross-sections. Charge attachment to nanofillers and nanocrystallites increase with vol.% loading or degree of crystallinity, and saturate at about 40 vol.%.

Keywords: nanocomposites, nanofillers, electrical double layer, bipolar charge transport

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2492 Effect of Cryogenic Pre-stretching on the Room Temperature Tensile Behavior of AZ61 Magnesium Alloy and Dominant Grain Growth Mechanisms During Subsequent Annealing

Authors: Umer Masood Chaudry, Hafiz Muhammad Rehan Tariq, Chung-soo Kim, Tea-sung Jun

Abstract:

This study explored the influence of pre-stretching temperature on the microstructural characteristics and deformation behavior of AZ61 magnesium alloy and its implications on grain growth during subsequent annealing. AZ61 alloy was stretched to 5% plastic strain along rolling (RD) and transverse direction (TD) at room (RT) and cryogenic temperature (-150 oC, CT) followed by annealing at 320 oC for 1 h to investigate the twinning and dislocation evolution and its consequent effect on the flow stress, plastic strain and strain hardening rate. Compared to RT-stretched samples, significant improvement in yield stress, strain hardening rate and moderate reduction in elongation to failure were witnessed for CT-stretched samples along RD and TD. The subsequent EBSD analysis revealed the increased fraction of fine {10-12} twins and nucleation of multiple {10-12} twin variants caused by higher local stress concentration at the grain boundaries in CT-stretched samples as manifested by the kernel average misorientation. This higher twin fraction and twin-twin interaction imposed the strengthening by restricting the mean free path of dislocations, leading to higher flow stress and strain hardening rate. During annealing of the RT/CT-stretched samples, the residual strain energy and twin boundaries were decreased due to static recovery, leading to a coarse-grained twin-free microstructure. Strain induced boundary migration (SBIM) was found to be the predominant mechanism governing the grain growth during annealing via movement of high angle grain boundaries.

Keywords: magnesium, twinning, twinning variant selection, EBSD, cryogenic deformation

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2491 Protecting the Financial Rights of Non-Member Spouses: Addressing the Exploitation of Retirement Benefits in South African Divorce Law

Authors: Ronelle Prinsloo

Abstract:

In South Africa, married retirement fund members can manipulate the legal framework to prevent their spouses from accessing shared retirement benefits during divorce proceedings. The current legal structure allows retirement fund members to accelerate the accrual of their benefits, often by resigning or purchasing living annuities before the finalization of a divorce. This action effectively places these benefits beyond the reach of their spouses, leading to substantial financial prejudice, particularly for financially weaker spouses, typically women. The research highlights that South African courts, including the Supreme Court of Appeal (SCA), have not adequately scrutinized the implications of these actions. Specifically, the SCA has ruled that the capital and proceeds from living annuities are not subject to division during divorce, which undermines the financial rights of non-member spouses. The court's failure to consider the source of the money used to purchase these annuities and its potential inclusion in the joint estate or accrual system is a significant concern. The South African Law Reform Commission has recognized this issue, noting the negative impact on financially weaker spouses. The article critiques the lack of legislative response to this problem despite its significant implications for the equitable distribution of marital assets. The current legal framework, particularly the definition of "pension interest" and the provisions under sections 7(7) and 7(8) of the Divorce Act, is inadequate in addressing the complexities surrounding the sharing of retirement benefits in divorce cases. The article argues for a comprehensive review and reform of the law to ensure that retirement benefits are treated as patrimonial assets, subject to division upon the occurrence of any trigger event, such as resignation, retirement, or retrenchment. The need for such reform is urgent to prevent economically disadvantaged spouses from being unjustly deprived of their fair share of retirement benefits. In conclusion, the article advocates for legislative amendments to the Divorce Act, specifically section 7(7), to clarify that pension interests automatically form part of the joint estate, regardless of whether divorce proceedings are underway. This change would safeguard the financial rights of non-member spouses and ensure a more equitable distribution of retirement benefits during divorce. Failure to address this issue perpetuates economic inequality and leaves financially weaker spouses vulnerable during divorce proceedings.

Keywords: Constitution of South Africa, non-member spouse, retirement benefits, spouse

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