Search results for: testing effectiveness

Authors: Vishal Mahale, Jayashree Bijwe, Sujeet K. Sinha

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Range of thermal conductivity (TC) of Friction Materials (FMs) is a critical issue since lower TC leads to accumulation of frictional heat on the working surface, which results in excessive fade while higher TC leads to excessive heat flow towards back-plate resulting in boiling of brake-fluid leading to ‘spongy brakes’. This phenomenon prohibits braking action, which is most undesirable. Therefore, TC of the FMs across the brake pads should not be high while along the brake pad, it should be high. To enhance TC, metals in the forms of powder and fibers are used in the FMs. Apart from TC improvement, metals provide strength and structural integrity to the composites. Due to higher TC Copper (Cu) powder/fiber is a most preferred metallic ingredient in FM industry. However, Cu powders/fibers are responsible for metallic wear debris generation, which has harmful effects on aquatic organisms. Hence to get rid of a problem of metallic wear debris generation and to keep the positive effect of TC improvement, incorporation of Cu fabric in NAO brake-pads can be an innovative solution. Keeping this in view, two realistic multi-ingredient FM composites with identical formulations were developed in the form of brake-pads. Out of which one composite series consisted of a single layer of Cu fabric in the body of brake-pad and designated as C1 while double layer of Cu fabric was incorporated in another brake-pad series with designation of C2. Distance of Cu fabric layer from the back-plate was kept constant for C1 and C2. One more composite (C0) was developed without Cu fabric for the sake of comparison. Developed composites were characterized for physical properties. Tribological performance was evaluated on full scale inertia dynamometer by following JASO C 406 testing standard. It was concluded that Cu fabric successfully improved fade resistance by increasing conductivity of the composite and also showed slight improvement in wear resistance. Worn surfaces of pads and disc were analyzed by SEM and EDAX to study wear mechanism.

Keywords: brake inertia dynamometer, copper fabric, non-asbestos organic (NAO) friction materials, thermal conductivity enhancement

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Authors: L. Vivet, L. Benabou, O. Simon

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With highly demanding applications in the field of power electronics, there is an increasing need to have interconnection materials with properties that can ensure both good mechanical assembly and high thermal/electrical conductivities. So far, lead-free solders have been considered an attractive solution, but recently, sintered joints based on nano-silver paste have been used for die attach and have proved to be a promising solution offering increased performances in high-temperature applications. In this work, the main parameters of the bonding process using silver oxalates are studied, i.e., the heating rate and the bonding pressure mainly. Their effects on both the mechanical and thermal properties of the sintered layer are evaluated following an experimental design. Pairs of copper substrates with gold metallization are assembled through the sintering process to realize the samples that are tested using a micro-traction machine. In addition, the obtained joints are examined through microscopy to identify the important microstructural features in relation to the measured properties. The formation of an intermetallic compound at the junction between the sintered silver layer and the gold metallization deposited on copper is also analyzed. Microscopy analysis exhibits a nanoporous structure of the sintered material. It is found that higher temperature and bonding pressure result in higher densification of the sintered material, with higher thermal conductivity of the joint but less mechanical flexibility to accommodate the thermo-mechanical stresses arising during service. The experimental design allows hence the determination of the optimal process parameters to reach sufficient thermal/mechanical properties for a given application. It is also found that the interphase formed between silver and gold metallization is the location where the fracture occurred after the mechanical testing, suggesting that the inter-diffusion mechanism between the different elements of the assembly leads to the formation of a relatively brittle compound.

Keywords: nanoporous structure, silver oxalate, sintering, mechanical strength, thermal conductivity, microelectronic packaging

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Authors: Ateba Benedict Belobo, Faan Pelser, Ambe Marcus

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Aims: This study arise from repeated complaints from both electronic mails about the underperformance of Mafikeng Small and Medium-Size enterprises after the global financial crisis. The authors were on the view that, this poor performance experienced could be as a result of the negative effects on the cash flow of these businesses due to volatilities in the business environment in general prior to the global crisis. Thus, the paper was mainly aimed at determining the shortcomings experienced by these SMEs with regards to cash flow management. It was also aimed at suggesting possible measures to improve cash flow management of these SMEs in this tough time. Methods: A case study was conducted on 3 beverage suppliers, 27 bottle stores, 3 largest fast consumer goods super markets and 7 automobiles enterprises in the Mafikeng local municipality. A mixed method research design was employed and a purposive sampling was used in selecting SMEs that participated. Views and experiences of participants of the paper were captured through in-depth interviews. Data from the empirical investigation were interpreted using open coding and a simple percentage formula. Results: Findings from the empirical research reflected that majority of Mafikeng SMEs suffer poor operational performance prior to the global financial crisis primarily as a result of poor cash flow management. However, the empirical outcome also indicted other secondary factors contributing to this poor operational performance. Conclusion: Finally, the authorsproposed possible measures that could be used to improve cash flow management and to solve other factors affecting operational performance of SMEs in the Mafikeng local municipality in other to achieve a better business performance.

Keywords: cash flow, business performance, global financial crisis, SMEs

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Authors: Ashley R. Logsdon, Becky F. Antle, Cynthia M. Kamer

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This study examines the cost and benefits of a family treatment drug court in an urban county in a southeastern state. Additionally, this cost analysis will provide a detailed description of the type and cost of activities to produce the services provided to child welfare families. This study utilized return-on-investment analysis, which uses child welfare practices, disaggregates them into separate activities and estimates costs for these activities including child-level placement data for total cost of care for the child. Direct and indirect costs were considered as well as saving calculations what costs would be associated with child welfare outcomes both short and long term. The costs included were general program costs (salaries, drug screens, transportation, childcare, parent education, program evaluation, visitation, incentives) or personnel costs for other team members (judges, court administrators, child welfare workers, child welfare supervisors, and community mental health provider). The savings that were used in the study were length of time in out of home care, Medicaid costs, substance exposed births, emergency room utilization and jail/probation costs. This study documents an overall savings of between $168,993.30 and $837,993.30. The total savings per family divided by the 40 families who have participated in the program was between $4,224.83 to $20,949.83 per family. The results of this cost benefit analysis are consistent with prior research documenting savings associated with out of home care and jail/probation; however, there are also unique contributions of this study to the literature on cost effectiveness of family treatment drug courts. We will present recommendations for further utilization of family treatment drug courts and how to expand the current model.

Keywords: child welfare, cost analysis, family drug court, family treatment drug court

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Authors: Peter W. Woodruff, Georgios Ponirakis, Reem Ibrahim, Amani Ahmed, Hoda Gad, Ioannis N. Petropoulos, Adnan Khan, Ahmed Elsotouhy, Surjith Vattoth, Mahmoud K. M. Alshawwaf, Mohamed Adil Shah Khoodoruth, Marwan Ramadan, Anjushri Bhagat, James Currie, Ziyad Mahfoud, Hanadi Al Hamad, Ahmed Own, Peter Haddad, Majid Alabdulla, Rayaz A. Malik

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Introduction:- We aimed to test the hypothesis that, using corneal confocal microscopy (a non-invasive method for assessing corneal nerve fibre integrity), patients with schizophrenia would show neuronal abnormalities compared with healthy participants. Schizophrenia is a neurodevelopmental and progressive neurodegenerative disease, for which there are no validated biomarkers. Corneal confocal microscopy (CCM) is a non-invasive ophthalmic imaging biomarker that can be used to detect neuronal abnormalities in neuropsychiatric syndromes. Methods:- Patients with schizophrenia (DSM-V criteria) without other causes of peripheral neuropathy and healthy controls underwent CCM, vibration perception threshold (VPT) and sudomotor function testing. The diagnostic accuracy of CCM in distinguishing patients from controls was assessed using the area under the curve (AUC) of the Receiver Operating Characterstics (ROC) curve. Findings:- Participants with schizophrenia (n=17) and controls (n=38) with comparable age (35.7±8.5 vs 35.6±12.2, P=0.96) were recruited. Patients with schizophrenia had significantly higher body weight (93.9±25.5 vs 77.1±10.1, P=0.02), lower Low Density Lipoproteins (2.6±1.0 vs 3.4±0.7, P=0.02), but comparable systolic and diastolic blood pressure, HbA1c, total cholesterol, triglycerides and High Density Lipoproteins were comparable with control participants. Patients with schizophrenia had significantly lower corneal nerve fiber density (CNFD, fibers/mm2) (23.5±7.8 vs 35.6±6.5, p<0.0001), branch density (CNBD, branches/mm2) (34.4±26.9 vs 98.1±30.6, p<0.0001), and fiber length (CNFL, mm/mm2) (14.3±4.7 vs 24.2±3.9, p<0.0001) but no difference in VPT (6.1±3.1 vs 4.5±2.8, p=0.12) and electrochemical skin conductance (61.0±24.0 vs 68.9±12.3, p=0.23) compared with controls. The diagnostic accuracy of CNFD, CNBD and CNFL to distinguish patients with schizophrenia from healthy controls were, according to the AUC, (95% CI): 87.0% (76.8-98.2), 93.2% (84.2-102.3), 93.2% (84.4-102.1), respectively. Conclusion:- In conclusion, CCM can be used to help identify neuronal changes and has a high diagnostic accuracy to distinguish subjects with schizophrenia from healthy controls.

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Authors: Murad Ghanim

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The citrus greening disease, also known as Huanglongbing, caused by the phloem-limited bacterium Candidatus Liberibacter asiaticus (CLas) has resulted in tremendous losses and the death of millions of citrus trees worldwide. CLas is transmitted by the Asian citrus psyllid (ACP) Diaphorina citri. The closely-related bacterium Candidatus Liberibacter solanacearum (CLso), which is associated with vegetative disorders in carrots and the zebra chips disease in potatoes, is transmitted by other psyllid species including Bactericera trigonica in carrots and B. ckockerelli in potatoes. Chemical sprays are currently the prevailing method for managing these diseases for limiting psyllid populations; however, they are limited in their effectiveness. A promising approach to prevent the transmission of these pathogens is to interfere with the vector-pathogen interactions, but our understanding of these processes is very limited. CLas induces changes in the nuclear architecture in the midgut of ACP and activates programmed cell death (apoptosis) in this organ. Strikingly, CLso displayed an opposite effect in the gut of B. trigonica, showing limited apoptosis, but widespread necrosis. Electron and fluorescent microscopy further showed that CLas induced the formation of Endoplasmic reticulum (ER) inclusion- and replication-like bodies, in which it increases and multiplies. ER involvement in bacterial replication is hypothesized to be the first stage of an immune response leading to the apoptotic and necrotic responses. ER exploitation and the subsequent events that lead to these cellular and stress responses might activate a cascade of molecular responses ending up with apoptosis and necrosis. Understanding the molecular interactions that underlay the necrotic/apoptotic responses to the bacteria will increase our knowledge of ACP-CLas, and BT-CLso interactions, and will set the foundation for developing novel, and efficient strategies to disturb these interactions and inhibit the transmission.

Keywords: Liberibacter, psyllid, transmission, apoptosis, necrosis

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Authors: Stephen W. Wang

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This research aims to explore the multi-faceted structure of airline passengers’ perception of airline sponsorship, and its impact on airline passengers and even consumers on airline brand preferences and brand equity. The connotation of this research is mainly divided into two parts. The first part of the research focuses on exploring the connotation and sub-dimensions of “air passengers’ perception of airline sponsorship”; the second part of the research focuses on integrating “air passengers’ perception on the multi-factor aspect of the corporate sponsorship, “brand transfer theory” and “brand theory”, explores the influence of airlines’ commitment to corporate sponsorship activities on the brand equity and brand preferences of airline passengers, and on passengers’ subsequent behavioral intentions . In addition, in order to clarify the differences between different types of corporate sponsorship activities and events in terms of "air passengers' perception of airline corporate sponsorship activities", brand transfer, brand preference, brand equity and behavioral intentions, this research also focuses on moderating effects of corporate sponsorship events. With the apply of multi-group structural equation model, it is hoped that the effectiveness of the sponsorship activities of airline companies will be improved. In terms of theoretical and practical implications, the aviation industry can follow the results of this research to understand which corporate sponsorship perceptions have a greater impact on consumers, which has important practical significance. The second part of the research project, from the consumer's point of view, understands whether airline corporate sponsorship activities influence behavioral intentions through brand transfer and brand recognition. Through the analysis of the intermediary effect of brand transfer, brand preference and brand equity, the results of this research can provide a more complete and powerful explanation for “why” airlines’ commitment to corporate sponsorship activities can affect airline passengers’ purchase intentions, which will help fill in the gap of the theoretical and practical research on "airline corporate sponsorship", and has its theoretical significance.

Keywords: airline, sponsorship, brand image transfer, brand preference

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Authors: Amr Sultan, Sara Elgazzar, Breksal Elmiligy

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The airline industry nowadays is becoming a more growing industry facing a severe competition. It is an influential issue in this context to utilize revenue management (RM) concept and practice in order to develop the pricing strategy. There is an unfathomable necessity for RM to assist the airlines and their associates to disparage the cost and recuperate their revenue, which in turn will boost the airline industry performance. The complexity of RM imposes enormous challenges on the airline industry. Several studies have been proposed on the RM adaptation in airlines industry while there is a limited availability of implementing RM and its complexity in the developing countries such as Egypt. This research represents a research schema about the implementation of the RM to the Egyptian airline industry. The research aims at investigating and demonstrating the complexities face implementing RM in the airline industry, up on which the research provides a comprehensive understanding of how to overcome these complexities while adapting RM in the Egyptian airline industry. An empirical study was conducted on the Egyptian airline sector based on a sample of four airlines (Egyptair, Britishair, KLM, and Lufthansa). The empirical study was conducted using a mix of qualitative and quantitative approaches. First, in-depth interviews were carried out to analyze the Egyptian airline sector status and the main challenges faced by the airlines. Then, a structured survey on the three different parties of airline industry; airlines, airfreight forwarders, and passengers were conducted in order to investigate the main complexity factors from different parties' points of view. Finally, a focus group was conducted to develop a best practice framework to overcome the complexities faced the RM adaptation in the Egyptian airline industry. The research provides an original contribution to knowledge by creating a framework to overcome the complexities and challenges in adapting RM in the airline industry generally and the Egyptian airline industry particularly. The framework can be used as a RM tool to increase the effectiveness and efficiency of the Egyptian airline industry performance.

Keywords: revenue management, airline industry, revenue management complexity, Egyptian airline industry

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Authors: Robyn L. Curran, Joanne R. Naidoo, Gugu Mchunu

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Along with the increasing awareness of human trafficking, is the acknowledgement that it is no longer just a social problem but also a significant public health problem that requires both increased knowledge and the specialist equipping of aftercare providers such as nurses who care for human trafficking survivors. Current discourse regarding aftercare of human trafficking survivors, is that approaches do not clearly explain the function or content of aftercare and what aftercare entails. Although psychological and medical aftercare are emphasized as important components, little practical attention is devoted to what these components actually involve and the effectiveness of current practice in aftercare. Review of the literature on the processes that take place from aftercare to empowerment, revealed the need for emphasis to be placed on the voices of survivors concerning their liberation from oppression. The aim of the study was to develop a theory for aftercare of human trafficking survivors, through analyzing the experiences of survivors and aftercare providers in shelters in three provinces in South Africa. Through using a Straussian grounded theory approach, the researcher developed a theory to inform care of human trafficking survivors in low resource settings using the voice of the survivors and those experienced in direct care of human trafficking survivors. Four human trafficking survivors and three aftercare providers from three shelters in three provinces in South Africa were individually interviewed in order for the theory to emerge. The findings of the study elicited a theoretical model of the renewed self, and the conditions that facilitate this process in care of human trafficking survivors. The process that human trafficking survivors navigate to empowerment require mutual collaboration of the aftercare provider and survivor as the survivor awakens vision, confronts reality, re-salvages autonomy and liberates self. Psychological resilience of the survivor facilitates the transition to renewed self. The recommendations of this study may improve the nursing care provided to human trafficking survivors and equip professionals with knowledge and skills to promote the process of renewing self for survivors.

Keywords: aftercare, aftercare providers, grounded theory, human trafficking survivors

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Authors: Natividad Natalia Angeles Manuel

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In the Dominican Republic, American-Dominican veterans face unique challenges due to their dual identities and wartime experiences. This case study examines an 85-year-old veteran with memory impairments and emotional distress linked to military service. A neuropsychological assessment using standardized tools evaluated cognitive domains and functional abilities. Significant deficits in memory, orientation, semantic memory, and executive functions, alongside symptoms of Post-Traumatic Stress Disorder and depression, were identified. A six-month cognitive stimulation program included tailored interventions to enhance memory, attention, and executive skills through weekly sessions and group activities. Medical and physical therapy support aimed to improve overall cognitive, functional, and emotional outcomes. Follow-up evaluations showed improvements in memory retention, attention, task proficiency, and reduced depressive symptoms, highlighting the program's effectiveness in promoting emotional well-being and quality of life. Despite ongoing memory challenges and military-related nightmares, the veteran responded positively to interventions, demonstrating resilience and motivation. This study emphasizes the importance of personalized neuropsychological interventions for American-Dominican veterans in the Dominican Republic. Through assessment tools and focused cognitive stimulation strategies, healthcare providers can successfully alleviate cognitive and emotional challenges stemming from traumatic experiences in elderly veterans. Overall, integrated neuropsychological assessment and stimulation programs are shown to enhance cognitive resilience and emotional well-being, thus contributing to an enhanced quality of life for aging American-Dominican veterans.

Keywords: neuropsychology, cognitive stimulation, American-Dominican veterans, Dominican Republic, PTSD, memory deficits

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Authors: Arawati Agus, Rahmah Ismail

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An effective training has been increasingly recognized as critical factors in enhancing the skills and knowledge of employee or personnel in the organization. More and more manufacturing companies in Malaysia are increasingly incorporating training as an important element in supply chain management (SCM) to improve their employee skills and knowledge and ultimately organizational performances. In order to understand the connection of training in SCM and the performance of an organization, this paper considers of many arguments from various research papers. This paper presents the findings of a research which examines the relationship between training in SCM, personnel differentiation and business performance of manufacturing companies in Malaysia. The study measures perception of senior management regarding the incorporation of training in SCM and the level of personnel differentiation and business performance measurements in their companies. The associations between training in SCM, personnel differentiation and business performance dimensions are analyzed through methods such as Pearson’s correlations and Smart partial least squares (smart PLS) using 126 respondents’ data. The correlation results demonstrate that training in SCM has significant correlations with personnel differentiation determinants (comprises of variables namely employee differentiation and service differentiation). The findings also suggest that training in SCM has significant correlations with business performance determinants (comprises of indicators, namely market share, profitability, ROA and ROS). Specifically, both personnel differentiation and business performance have high correlations with training in SCM, namely ‘Employee training on production skills’, ‘On the job production employee training’ and ‘Management training on supply chain effectiveness’ and ‘Employee training on supply chain technologies’. The smart PLS result also reveals that training in SCM exhibits significant impact on both personnel differentiation (directly) and business performance (indirectly mediated by personnel differentiation). The findings of the study provide a demonstration of the importance of training in SCM in enhancing competitive performances in Malaysian manufacturing companies.

Keywords: training in SCM, personnel differentiation, business performance, Pearson’s correlation, Smart PLS

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Authors: Michał Jaśkiewicz

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The relation between walkability, place adherence, social relations and quality of life was explored in a Polish context. A considerable number of studies have suggested that environmental factors may influence the quality of life through indirect pathways. The list of possible psychological mediators includes social relations and identity-related variables. Based on the results of Study 1, local identity is a significant mediator in the relationship between neighbourhood walkability and quality of life. It was assumed that pedestrian-oriented neighbourhoods enable residents to interact and that these spontaneous interactions can help to strengthen a sense of local identity, thus influencing the quality of life. We, therefore, conducted further studies, testing the relationship experimentally in studies 2a and 2b. Participants were exposed to (2a) photos of walkable/non-walkable neighbourhoods or (2b) descriptions of high/low-walkable neighbourhoods. They were then asked to assess the walkability of the neighbourhoods and to evaluate their potential social relations and quality of life in these places. In both studies, social relations with neighbours turned out to be a significant mediator between walkability and quality of life. In Study 3, we implemented the measure of overlapping individual and communal identity (fusion with the neighbourhood) and willingness to collective action as mediators. Living in a walkable neighbourhood was associated with identity fusion with that neighbourhood. Participants who felt more fused expressed greater willingness to engage in collective action with other neighbours. Finally, this willingness was positively related to the quality of life in the city. In Study 4, we used commuting time (an aspect of walkability related to the time that people spend travelling to work) as the independent variable. The results showed that a shorter average daily commuting time was linked to more frequent social interactions in the neighbourhood. Individuals who assessed their social interactions as more frequent expressed a stronger city identification, which was in turn related to quality of life. To sum up, our research replicated and extended previous findings on the association between walkability and well-being measures. We introduced potential mediators of this relationship: social interactions in the neighbourhood and identity-related variables.

Keywords: walkability, quality of life, social relations, analysis of mediation

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Authors: José Luis Gallizo, Pilar Gargallo, Ramon Saladrigues, Manuel Salvador

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This study offers an exploratory statistical analysis of the persistence of annual profits across a sample of firms from different European Union (EU) countries. To this end, a hierarchical Bayesian dynamic model has been used which enables the annual behaviour of those profits to be broken down into a permanent structural and a transitory component, while also distinguishing between general effects affecting the industry as a whole to which each firm belongs and specific effects affecting each firm in particular. This breakdown enables the relative importance of those fundamental components to be more accurately evaluated by country and sector. Furthermore, Bayesian approach allows for testing different hypotheses about the homogeneity of the behaviour of the above components with respect to the sector and the country where the firm develops its activity. The data analysed come from a sample of 23,293 firms in EU countries selected from the AMADEUS data-base. The period analysed ran from 1999 to 2007 and 21 sectors were analysed, chosen in such a way that there was a sufficiently large number of firms in each country sector combination for the industry effects to be estimated accurately enough for meaningful comparisons to be made by sector and country. The analysis has been conducted by sector and by country from a Bayesian perspective, thus making the study more flexible and realistic since the estimates obtained do not depend on asymptotic results. In general terms, the study finds that, although the industry effects are significant, more important are the firm specific effects. That importance varies depending on the sector or the country in which the firm carries out its activity. The influence of firm effects accounts for around 81% of total variation and display a significantly lower degree of persistence, with adjustment speeds oscillating around 34%. However, this pattern is not homogeneous but depends on the sector and country analysed. Industry effects depends also on sector and country analysed have a more marginal importance, being significantly more persistent, with adjustment speeds oscillating around 7-8% with this degree of persistence being very similar for most of sectors and countries analysed.

Keywords: dynamic models, Bayesian inference, MCMC, abnormal returns, persistence of profits, return on assets

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Authors: Camille Lacan, Pierre Desmet

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In the crowdfunding model, a campaign succeeds by collecting the funds required over a predefined duration. The success of a CF campaign depends both on the capacity to attract members of the online communities concerned, and on the community members’ involvement in online word-of-mouth recommendations. To maximize the campaign's success probability, project creators (i.e., an organization appealing for financial resources) send messages to contributors to ask them to issue word of mouth. Internet users relay information about projects through Word of Mouth which is defined as “a critical tool for facilitating information diffusion throughout online communities”. The effectiveness of these messages depends on the message framing and the time at which they are sent to contributors (i.e., at the start of the campaign or close to the deadline). This article addresses the following question: What are the effect of message framing and temporal distance on the willingness to share word of mouth? Drawing on Perspectives Theory and Construal Level Theory, this study examines the interplay between message framing (Gains vs. Losses) and temporal distance (message while the deadline is coming vs. far) on intention to share word of mouth. A between-subject experimental design is conducted to test the research model. Results show significant differences between a loss-framed message (lack of benefits if the campaign fails) associated with a short deadline (ending tomorrow) compared to a gain-framed message (benefits if the campaign succeeds) associated with a distant deadline (ending in three months). However, this effect is moderated by the anticipated regret of a campaign failure and the temporal orientation. These moderating effects contribute to specifying the boundary condition of the framing effect. Handling the message framing and the temporal distance are thus the key decisions to influence the willingness to share word of mouth.

Keywords: construal levels, crowdfunding, message framing, word of mouth

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Authors: Camila Parodi, Viviana Letelier, Giacomo Moriconi

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The cement industry is responsible for around a 5% of the CO2 emissions worldwide and considering that concrete is one of the most used materials in construction its total effect is important. An alternative to reduce the environmental impact of concrete production is to incorporate certain amount of residues in the dosing, limiting the replacement percentages to avoid significant losses in the mechanical properties of the final material. Previous researches demonstrate the feasibility of using brick and rust residues, separately, as a cement replacement. This study analyses the variation in the mechanical properties of mortars by incorporating masonry residue composed of clay bricks and cement mortar. In order to improve the mechanical properties of masonry residue, this was subjected to a heat treatment of 650 ° C for four hours and its effect is analyzed in this study. Masonry residue was obtained from a demolition of masonry perimetral walls. The residues were crushed and sieved and the maximum size of particles used was 75 microns. The percentages of cement replaced by masonry residue were 0%, 10%, 20% and 30%. The effect of masonry residue addition and its heat treatment in the mechanical properties of mortars is evaluated through compressive and flexural strength tests after 7, 14 and 28 curing days. Results show that increasing the amount of masonry residue used increases the losses in compressive strength and flexural strength. However, the use of up to a 20% of masonry residue, when a heat treatment is applied, allows obtaining mortars with similar compressive strength to the control mortar. Masonry residues mortars without a heat treatment show losses in compressive strengths between 15% and 27% with respect to masonry residues with heat treatment, which demonstrates the effectiveness of the heat treatment. From this analysis it can be conclude that it is possible to use up to 20% of masonry residue with heat treatment as cement replacement without significant losses in mortars mechanical properties, reducing considerably the environmental impact of the final material.

Keywords: cement replacement, environmental impact, masonry residue, mechanical properties of recycled mortars

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Authors: Freddy Munzhelele

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Setting: the empirical research has shown that the life cycle theory has an impact on the firms’ financing decisions, particularly the dividend pay-outs. Accordingly, the life cycle theory posits that as a firm matures, it gets to a level and capacity where it distributes more cash as dividends. On the other hand, the young firms prioritise investment opportunities sets and their financing; thus, they pay little or no dividends. The research on firms’ financing decisions also demonstrated, among others, the adoption of trade-off and pecking order theories on the dynamics of firms capital structure. The trade-off theory talks to firms holding a favourable position regarding debt structures particularly as to the cost and benefits thereof; and pecking order is concerned with firms preferring a hierarchical order as to choosing financing sources. The case of life cycle hypothesis explaining the financial managers’ decisions as regards the firms’ capital structure dynamics appears to be an interesting link, yet this link has been neglected in corporate finance research. If this link is to be explored as an empirical research, the financial decision-making alternatives will be enhanced immensely, since no conclusive evidence has been found yet as to the dynamics of capital structure. Aim: the aim of this study is to examine the impact of life cycle theory on the capital structure dynamics trade-off and pecking order theories of firms listed in retail, industrial and mining sectors of the JSE. These sectors are among the key contributors to the GDP in the South African economy. Design and methodology: following the postpositivist research paradigm, the study is quantitative in nature and utilises secondary data obtainable from the financial statements of sampled firm for the period 2010 – 2022. The firms’ financial statements will be extracted from the IRESS database. Since the data will be in panel form, a combination of the static and dynamic panel data estimators will used to analyse data. The overall data analyses will be done using STATA program. Value add: this study directly investigates the link between the life cycle theory and the dynamics of capital structure decisions, particularly the trade-off and pecking order theories.

Keywords: life cycle theory, trade-off theory, pecking order theory, capital structure, JSE listed firms

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Authors: Lancer Scott

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Purpose: High quality clinical disaster medicine requires providers working collaboratively to care for multiple patients in chaotic environments; however, many providers lack adequate training. To address this deficit, we created a competency-based, 5-hour Emergency Preparedness Training (EPT) curriculum using didactics, small-group discussion, and kinetic learning. The goal was to evaluate the effect of a short course on improving provider knowledge, confidence and skills in disaster scenarios. Methods: Diverse groups of medical university students, health care professionals, and community members were enrolled between 2011 and 2014. The course consisted of didactic lectures, small group exercises, and two live, multi-patient mass casualty incident (MCI) scenarios. The outcome measures were based on core competencies and performance objectives developed by a curriculum task force and assessed via trained facilitator observation, pre- and post-testing, and a course evaluation. Results: 708 participants completed were trained between November 2011 and August 2014, including 49.9% physicians, 31.9% medical students, 7.2% nurses, and 11% various other healthcare professions. 100% of participants completed the pre-test and 71.9% completed the post-test, with average correct answers increasing from 39% to 60%. Following didactics, trainees met 73% and 96% of performance objectives for the two small group exercises and 68.5% and 61.1% of performance objectives for the two MCI scenarios. Average trainee self-assessment of both overall knowledge and skill with clinical disasters improved from 33/100 to 74/100 (overall knowledge) and 33/100 to 77/100 (overall skill). The course assessment was completed by 34.3% participants, of whom 91.5% highly recommended the course. Conclusion: A relatively short, intensive EPT course can improve the ability of a diverse group of disaster care providers to respond effectively to mass casualty scenarios.

Keywords: clinical disaster medicine, training, hospital preparedness, surge capacity, education, curriculum, research, performance, training, student, physicians, nurses, health care providers, health care

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Authors: Hossein Rassi, Marjan Moradi Fard, Masoud Houshmand

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Background: Cervical cancer is multistep disease that is thought to result from an interaction between genetic background and environmental factors. Human papillomavirus (HPV) infection is the leading risk factor for cervical intraepithelial neoplasia (CIN) and cervical cancer. In other hand, some of p53 and miRNA polymorphism may plays an important role in carcinogenesis. This study attempts to clarify the relation of p53 genotypes and miR-146a rs2910164 polymorphism in cervical lesions. Method: Forty two archival samples with cervical lesion retired from Khatam hospital and 40 sample from healthy persons used as control group. A simple and rapid method was used to detect the simultaneous amplification of the HPV consensus L1 region and HPV-16,-18, -11, -31, 33 and -35 along with the b-globin gene as an internal control. We use Multiplex PCR for detection of P53 and miR-146a rs2910164 genotypes in our lab. Finally, data analysis was performed using the 7 version of the Epi Info(TM) 2012 software and test chi-square(x2) for trend. Results: Cervix lesions were collected from 42 patients with Squamous metaplasia, cervical intraepithelial neoplasia, and cervical carcinoma. Successful DNA extraction was assessed by PCR amplification of b-actin gene (99bp). According to the results, p53 GG genotype and miR-146a rs2910164 CC genotype was significantly associated with increased risk of cervical lesions in the study population. In this study, we detected 13 HPV 18 from 42 cervical cancer. Conclusion: The connection between several SNP polymorphism and human virus papilloma in rare researches were seen. The reason of these differences in researches' findings can result in different kinds of races and geographic situations and also differences in life grooves in every region. The present study provided preliminary evidence that a p53 GG genotype and miR-146a rs2910164 CC genotype may effect cervical cancer risk in the study population, interacting synergistically with HPV 18 genotype. Our results demonstrate that the testing of p53 codon 72 polymorphism genotypes and miR-146a rs2910164 polymorphism genotypes in combination with HPV18 can serve as major risk factors in the early identification of cervical cancers. Furthermore, the results indicate the possibility of primary prevention of cervical cancer by vaccination against HPV18 in Iran.

Keywords: cervical cancer, HPV18, p53 codon 72 polymorphism, miR-146a rs2910164 polymorphism

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Authors: Chi-Hsuan Cheng

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This research aims to evaluate public-private partnerships against cyberattacks by comparing the UK and Taiwan. First, the study analyses major cyberattacks and factors influencing cybersecurity in both countries. Second, it assesses the effectiveness of current cyber defence strategies in combating cyberattacks by comparing the approaches taken in the UK and Taiwan, while also evaluating the cyber resilience of both nations. Lastly, the research evaluates existing public-private partnerships by comparing those in the UK and Taiwan, and proposes recommendations for enhancing cooperation and collaboration mechanisms in tackling cyberattacks. Grounded theory serves as the core research method. Theoretical sampling is used to recruit participants in both the UK and Taiwan, including investigators, police officers, and professionals from cybersecurity firms. Semi-structured interviews are conducted in English in the UK and Mandarin in Taiwan, recorded with consent, and pseudonymised for privacy. Data analysis involves open coding, grouping excerpts into codes, and categorising codes. Axial coding connects codes into categories, leading to the development of a codebook. The process continues iteratively until theoretical saturation is reached. Finally, selective coding identifies the core topic, evaluating public-private cooperation against cyberattacks and its implications for social and policing strategies in the UK and Taiwan, which highlights the current status of the cybersecurity industry, governmental plans for cybersecurity, and contributions to cybersecurity from both government sectors and cybersecurity firms, with a particular focus on public-private partnerships. In summary, this research aims to offer practical recommendations to law enforcement, private sectors, and academia for reflecting on current strategies and tailoring future approaches in cybersecurity

Keywords: cybersecurity, cybercrime, public private partnerships, cyberattack

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Authors: Raquib Ahsan, Md. Mahir Asif, Md. Zahidul Alam

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A huge portion of old masonry buildings in Bangladesh are vulnerable to earthquake. In most of the cases these buildings contain unreinforced masonry wall which are most likely to be subjected to earthquake damages. Due to deterioration of mortar joint and aging, shear resistance of these unreinforced masonry walls dwindle. So, retrofitting of these old buildings has become an important issue. Among many researched and experimented techniques, ferrocement retrofitting can be a low cost technique in context of the economic condition of Bangladesh. This study aims at investigating the behavior of ferrocement retrofitted unconfined URM walls under different types of cyclic loading. Four 725 mm × 725 mm masonry wall units were prepared with bricks jointed by stretcher bond with 12.5 mm mortar between two adjacent layers of bricks. To compare the effectiveness of ferrocement retrofitting a particular type wire mesh was used in this experiment which is 20 gauge woven wire mesh with 12.5 mm × 12.5 mm square opening. After retrofitting with ferrocement these wall units were tested by applying cyclic deformation along the diagonals of the specimens. Then a comparative study was performed between the retrofitted specimens and control specimens for both partially reversed cyclic load condition and cyclic compression load condition. The experiment results show that ultimate load carrying capacities of ferrocement retrofitted specimens are 35% and 27% greater than the control specimen under partially reversed cyclic loading and cyclic compression respectively. And before failure the deformations of ferrocement retrofitted specimens are 43% and 33% greater than the control specimen under reversed cyclic loading and cyclic compression respectively. Therefore, the test results show that the ultimate load carrying capacity and ductility of ferrocement retrofitted specimens have improved.

Keywords: cyclic compression, cyclic loading, ferrocement, masonry wall, partially reversed cyclic load, retrofitting

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Authors: Nneka U. Igboeli, Maxwell O. Adibe

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Iron and folate supplementation in pregnancy are important interventions that prevent maternal anaemia and fetal anomaly. Thus, daily oral doses of iron and folic acid are recommended throughout pregnancy as part of antenatal care. However, low adherence has been a major drawback leading to low effectiveness of these programs. The effect of mobile text message reminders to pregnant women to take their routine medications on adherence was evaluated in this study. The first 100 women who consented to the study were recruited and randomized to either receive a text message reminder on adherence to routine medications or not. Adherence was assessed using the 8-item Modified Morisky Adherence Scale (8-MMAS). The folders of successfully recruited women were tagged with the a study number assigned to each of them. The womens’ phone numbers were collected and these were used to send text messages reminders on adhering to routine drugs only to women in the intervention group. The text messages were sent three times per week for a period of four weeks with an adherence reassessment at the one month follow-up antenatal visit for recruited women. At one month follow-up, the lost to follow-up were 6 (16%) women for the intervention group and 17 (34%) for the control group. The across group mean difference in adherence score was 0.07 (-0.96 – 1.10) at baseline and 0.3 (-0.31 – 0.92) after intervention, both insignificant at p > 0.05. The within group change were increases of 0.58 (0.00 – 1.16) (p = 0.05) from baseline for the intervention group and a 0.35 (-0.51 – 1.20) (p = 0.395) for the control group. Non-significant increase in adherence scores were recorded for both groups. However, the increase in adherence scores of women in the intervention group was greater and may be potentially transformed into more positive results if the study period is increased with possibly reduced study drop-outs shows great promise for more positive results.

Keywords: adherence, mobile phone, pregnant women, reminders

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Authors: Maimuna Akram, Khadija Zia, Sohaib Naseer

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Pedagogical objectives and the nature of the course content may lead instructors to take varied approaches to selecting a student for the cold call, specifically in a studio setup where students work on different projects independently and show progress work time to time at scheduled critiques. Cold-calling often proves to be an effective tool in eliciting a response without enforcing judgment onto the recipients. While there is a mixed range of behavior exhibited by students who are cold-called, a classification of responses from anxiety-provoking to inspiring may be elicited; there is a need for a greater understanding of utilizing the exchanges in bringing about fruitful and engaging outcomes of studio discussions. This study aims to unravel the dimensions of utilizing the cold-call approach in a didactic exchange within studio pedagogy. A questionnaire survey was conducted in an undergraduate class at Arts and Design School. The impact of cold calling on students’ participation was determined through various parameters, including course choice, participation frequency, students’ comfortability, and teaching methodology. After analyzing the surveys, specific classroom teachers were interviewed to provide a qualitative perspective of the faculty. It was concluded that cold-calling increases students’ participation frequency and also increases preparation for class. Around 67% of students responded that teaching methods play an important role in learning activities and students’ participation during class discussions. 84% of participants agreed that cold calling is an effective way of learning. According to research, cold-calling can be done in large numbers without making students uncomfortable. As a result, the findings of this study support the use of this instructional method to encourage more students to participate in class discussions.

Keywords: active learning, class discussion, class participation, cold calling, pedagogical methods, student engagement

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Authors: S. Priya

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A project based learning assignment in English for Specific Purposes (ESP) context based on Communicative English as prescribed in the university syllabus for engineering students and its learning outcome from ESP context is the focus of analysis through this paper. The task based on Project Based Learning (PBL) was conducted in the digital language lab which had audio visual aids to support the team presentation. The total strength of 48 students of Mechanical Branch were divided into 6 groups, each consisting of 8 students. The group members were selected on random numbering basis. They were given a group task to represent a power point presentation on a topic related to their core branch. They had to discuss the issue and choose their topic and represent in a given format. It provided the individual role of each member in the presentation. A brief overview of the project and the outcome of its technical aspects were also had to be included. Each group had to highlight the contributions of that innovative technology through their presentation. The power point should be provided in a CD format. The variations in the choice of subjects, their usage of digital technologies, co-ordination for competition, learning experience of first time stage presentation, challenges of team cohesiveness were some criteria observed as their learning experience. For many other students undergoing the stages of planning, preparation and practice as steps for presentation had been the learning outcomes as given through their feedback form. The evaluation pattern is distributed for individual contribution and group effectiveness which promotes quality of presentation. The evaluated skills are communication skills, group cohesiveness, and audience response, quality of technicality and usage of technical terms. This paper thus analyses how project based learning improves the communication, life skills and technical skills in English for Specific learning context through PBL.

Keywords: language lab, ESP context, communicative skills, life skills

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Authors: Molin A., De Ramos J. M., Cadion L. G., Pico R. L.

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Malnutrition and food insecurity represent significant global challenges affecting millions of individuals, particularly in low-income and developing regions. The researchers created a solar-powered enzymatic composting bioreactor with an Arduino-based monitoring system for pH, humidity, and temperature. It manages mixed municipal solid wastes incorporating industrial enzymes and whey additives for accelerated composting and minimized carbon footprint. Within 15 days, the bioreactor yielded 54.54% compost compared to 44.85% from traditional methods, increasing yield by nearly 10%. Tests showed that the bioreactor compost had 4.84% NPK, passing metal analysis standards, while the traditional pit compost had 3.86% NPK; both are suitable for agriculture. Statistical analyses, including ANOVA and Tukey's HSD test, revealed significant differences in agricultural yield across different compost types based on leaf length, width, and number of leaves. The study compared the effects of different composts on Brassica rapa subsp. Chinesis (Petchay) and Brassica juncea (Mustasa) plant growth. For Pechay, significant effects of compost type on plant leaf length (F(5,84) = 62.33, η² = 0.79) and leaf width (F(5,84) = 12.35, η² = 0.42) were found. For Mustasa, significant effects of compost type on leaf length (F(4,70) = 20.61, η² = 0.54), leaf width (F(4,70) = 19.24, η² = 0.52), and number of leaves (F(4,70) = 13.17, η² = 0.43) were observed. This study explores the effectiveness of the enzymatic composting bioreactor and its viability in promoting carbon farming as a solution to food insecurity and malnutrition.

Keywords: malnutrition, food insecurity, enzymatic composting bioreactor, arduino-based monitoring system, enzymes, carbon farming, whey additive, NPK level

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Authors: Michael Salib, Samer Ezeldin, Ahmed Waly

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There are numerous challenges and problems facing the construction industry in several countries in the Middle East, as a result of numerous economic and political effects. As an example in Egypt, several construction companies have shut down and left the market since 2016. The closure of these companies occurred, as they did not respond with the suitable techniques and strategies that will enable them to survive during this economic turmoil period. A research is conducted in order to identify adequate strategies to be implemented by the Egyptian contractors that could allow them survive and keep competing during such economic hardship period. Two different techniques were used in order to identify these startegies. First, a deep research were conducted on the companies located in countries that suffered similar economic harship to identify the strategies they used in order to survive. Second, interviews were conducted with experts in the construction field in order to list the effective strategies they used that allowed them to survive. Moreover, at the end of each interview, the experts were asked to rate the applicability of the previously identified strategies used in the foreign countries, then the efficiency of each strategy if used in Egypt. A framework model is developed in order to assist the construction companies in choosing the suitable techniques to their company size, through identifying the top ranked strategies and techniques that should be adopted by the company based on the parameters given to the model. In order to verify this framework, the financial statements of two leading companies in the Egyptian construction market were studied. The first Contractor has applied nearly all the top ranked strategies identified in this paper, while the other contractor has applied only few of the identified top ranked strategies. Finally, another expert interviews were conducted in order to validate the framework. These experts were asked to test the model and rate through a questionnaire its applicability and effectiveness.

Keywords: construction management, economic hardship, recession, survive

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Authors: Sangita Pokhrel, Nalinda Somasiri, Rebecca Jeyavadhanam, Swathi Ganesan

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Tourism is a booming industry with huge future potential for global wealth and employment. There are countless data generated over social media sites every day, creating numerous opportunities to bring more insights to decision-makers. The integration of Big Data Technology into the tourism industry will allow companies to conclude where their customers have been and what they like. This information can then be used by businesses, such as those in charge of managing visitor centers or hotels, etc., and the tourist can get a clear idea of places before visiting. The technical perspective of natural language is processed by analysing the sentiment features of online reviews from tourists, and we then supply an enhanced long short-term memory (LSTM) framework for sentiment feature extraction of travel reviews. We have constructed a web review database using a crawler and web scraping technique for experimental validation to evaluate the effectiveness of our methodology. The text form of sentences was first classified through Vader and Roberta model to get the polarity of the reviews. In this paper, we have conducted study methods for feature extraction, such as Count Vectorization and TFIDF Vectorization, and implemented Convolutional Neural Network (CNN) classifier algorithm for the sentiment analysis to decide the tourist’s attitude towards the destinations is positive, negative, or simply neutral based on the review text that they posted online. The results demonstrated that from the CNN algorithm, after pre-processing and cleaning the dataset, we received an accuracy of 96.12% for the positive and negative sentiment analysis.

Keywords: counter vectorization, convolutional neural network, crawler, data technology, long short-term memory, web scraping, sentiment analysis

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Authors: Bintou Jobe

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Musculo-skeletal disorders (MSDs) are injuries or disorders of the spine disc, muscle strains, and low back injuries. It remains a major cause of occupational illness. Findings: Due to poor grips during handling, it is possible for neck, shoulder, arm, knees, ankle, fingers, waist, lower back injuries, and other muscle joints to be affected. Pregnant women are more prone to physical and hormonal changes, which lead to the relaxation of supporting ligaments. MSD continues to pose a global concern due to its impact on workers worldwide. The prevalence of the disorder is high, according to research into the workforce in Europe and developing countries. The causes are characterized by long working hours, insufficient rest breaks, poor posture, repetitive motion, poor manual handling techniques, psychological stress, and poor nutrition. To prevent MSD, the design mainly involves avoiding and assessing the risk. However, clinical solutions, policy governance, and minimizing manual labour are also an alternative. In addition, eating a balanced diet and teamwork force are key to elements in minimising the risk. This review aims to raise awareness and promote cost effectiveness prevention and understanding of MSD through research and identify proposed solutions to recognise the underlying causes of MSDs in the construction sectors. The methodology involves a literature review approach, engaging with the policy landscape of MSD, synthesising publications on MSD and a wider range of academic publications. In conclusion, training on effective manual handling techniques should be considered, and Personal Protective Equipment should be a last resort. The implementation of training guidelines has yielded significant benefits.

Keywords: musculoskeletal disorder work related, MSD, manual handling, work hazards

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Authors: Renee Fabian, Jordan Davidson

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Current research on non-suicidal self-injury (NSSI) provides ample insights on best practices for caregivers and clinicians to address and reduce NSSI behavior among adolescents. However, the efficacy of evidenced-based NSSI interventions and their delivery from the perspective of adolescent patients does not receive significant attention, creating a gap between the efficacy of research-based NSSI interventions and adolescent perceptions of NSSI treatment and adolescent willingness to engage in NSSI interventions. To address the gap between practice and patient perspectives and inform more effective treatment outcomes, the current survey aims to identify major patient-reported adverse reactions to NSSI disclosures from caregivers, treating mental health clinicians, and medical professionals using a mixed methods survey of 2,500 people with a history of NSSI completed by editors at a consumer-facing health publication. Based on the analyzed results of the survey, a majority of adolescents with a history of NSSI found parents and caregivers ineffective at empathetically addressing NSSI, and a significant number of participants reported at least one treating mental health professional inadequately responded to NSSI behaviors, in addition to other findings of adverse reactions to NSSI disclosures that serve as a barrier to treatment. NSSI is a significant risk factor for future suicide attempts. Addressing patient-reported adverse reactions to NSSI disclosures in the adolescent population can remove barriers to the effectiveness of caregiver and clinician NSSI interventions and reduce the risk of NSSI-related harm and lower the risk of future suicide attempts or completions.

Keywords: adolescent self-injury, non-suicidal self-injury, patient perspectives, self-harm interventions

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Authors: Gal Zagron, Nitza Abramson, Deena R. Zimmerman, Chen Stein-Zamir

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Background: Salmonella enteritidis is a common cause of foodborne outbreaks, primarily associated with poultry eggs. S. enteritidis This is the only Salmonella type that is found inside the eggshell. A rise in Salmonella enteritidis notifications was noted in spring 2017. Aims: The aim of this study is to describe the epidemiological investigation of the outbreak in the Jerusalem district, along with the containment measures taken. Methods: This study is a population-based epidemiological study with a description of environmental control activities. Results: During the months May - July, 2017 848 salmonellosis cases were reported to the Jerusalem district health office compared to 294 cases May - July 2016. Salmonella enteritidis was isolated in 58% of reported cases. Clusters and outbreaks ( > 2 cases) were reported among nursery schools, nursing homes, persons residing in one kibbutz and several cases in different food service establishments in the Jerusalem district. Epidemiological investigations revealed eggs consumption as a common feature among the cases (uncooked or undercooked eggs in most cases). A national investigation among egg suppliers revealed that most cases consumed eggs provided by a single provider with isolation of Salmonella enteritidis at the source as well. Containment measures were taken to control the epidemic including distributing information via electronic and written media to the public, searching for all egg distribution centers, informing local authorities, the poultry council and food stores. The eggs originating from the provider were recalled and extinguished. Written instructions to all food preparation facilities in the district were distributed regarding the proper storage and preparation of eggs. The number of reported cases declined and the outbreak vanished during correlating months of 2018. Conclusions: The investigation of Salmonella enteritidis outbreaks should include epidemiological and laboratory investigations, tracing the source of the eggs and testing the eggs and the source of eggs. Health education activities are essential as to the proper handling of eggs and egg products aiming to minimize susceptibility to Salmonella infection.

Keywords: epidemiological investigation, food-borne disease, food safety, Salmonella enteritidis

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Authors: Alan T. Sassler

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Biofouling is a significant issue for ships, especially those based in warm water ports. Biofouling damages hull coatings, degrades platform hydrodynamics, blocks cooling water intakes, and returns, reduces platform range and speed, and increases fuel consumption. Although platforms are protected to some degree by antifouling paints, these paints are much less effective on stationary platforms, and problematic biofouling can occur on antifouling paint-protected stationary platforms in some environments in as little as a matter of weeks. Remediation hull cleaning operations are possible, but they are very expensive, sometimes result in damage to the vessel’s paint or hull and are generally not completely effective. Ultrasound with sufficient intensity focused on specific frequency ranges can be used to prevent the growth of biofouling organisms. The use of ultrasound to prevent biofouling isn't new, but systems to date have focused on protecting platforms by shaking the hull using internally mounted transducers similar to those used in ultrasonic cleaning machines. While potentially effective, this methodology doesn't scale well to large platforms, and there are significant costs associated with installing and maintaining these systems, which dwarf the initial purchase price. An alternative approach has been developed, which uses highly directional pier-mounted transducers to project high-intensity spread-spectrum ultrasonic energy into the water column focused near the surface. This focused energy has been shown to prevent biofouling at ranges of up to 50 meters from the source. Spreading the energy out over a multi-kilohertz band makes the system both more effective and more environmentally friendly. This system has been shown to be both effective and inexpensive in small-scale testing and is now being characterized on a larger scale in selected marinas. To date, test results have been collected in Florida marinas suggesting that this approach can be used to keep ensonified areas of thousands of square meters free from biofouling, although care must be taken to minimize shaded areas.

Keywords: biofouling, ultrasonic, environmentally friendly antifoulant, marine protection, antifouling

Procedia PDF Downloads 47