Search results for: specific absorption rate

Authors: Abdul Umaro Tholley

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The preservation and packaging of cucumbers are essential to maintain their shelf life and quality. Cucumbers are a perishable food item that is highly susceptible to spoilage due to their high-water content and delicate nature. Therefore, proper preservation and packaging techniques are crucial to extend their shelf life and prevent economic loss. There are several methods of preserving cucumbers, including refrigeration, canning, pickling, and dehydration. Refrigeration is the most used preservation method, as it slows down the rate of deterioration and maintains the freshness and quality of the cucumbers. Canning and pickling are also popular preservation methods that use heat treatment and acidic solutions, respectively, to prevent microbial growth and increase shelf life. Dehydration involves removing the water content from cucumbers to increase their shelf life, but it may affect their texture and taste. Packaging also plays a vital role in preserving cucumbers. The packaging materials should be selected based on their ability to maintain the quality and freshness of the cucumbers. The most used packaging materials for cucumbers are polyethylene bags, which prevent moisture loss and protect the cucumbers from physical damage. Other packaging materials, such as corrugated boxes and wooden crates, may also be used, but they offer less protection against moisture loss and damage. The quality of cucumbers is affected by several factors, including storage temperature, humidity, and exposure to light. Cucumbers should be stored at temperatures between 7 and 10 °C, with a relative humidity of 90-95%, to maintain their freshness and quality. Exposure to light should also be minimized to prevent the formation of yellowing and decay. In conclusion, the preservation and packaging of cucumbers are essential to maintain their quality and extend their shelf life. Refrigeration, canning, pickling, and dehydration are common preservation methods that can be used to preserve cucumbers. The packaging materials used should be carefully selected to prevent moisture loss and physical damage. Proper storage conditions, such as temperature, humidity, and light exposure, should also be maintained to ensure the quality and freshness of cucumbers. Overall, proper preservation and packaging techniques can help reduce economic loss and provide consumers with high-quality cucumbers.

Keywords: cucumbers, preservation, packaging, shelf life

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Authors: Shunyi Yang, Jingjing Yan, Siyu Dong, Xiangguo Cui

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Current architectural façade design practices incorporate various daylighting and solar radiation analysis methods. These emphasize the impact of geometry on façade design. There is scope to extend this knowledge into methods that address material translucency, porosity, and form. Such approaches can also achieve these conditions through adaptive robotic manufacturing approaches that exploit material dynamics within the design, and alleviate fabrication waste from molds, ultimately accelerating the autonomous manufacturing system. Besides analyzing the environmental solar radiant in building facade design, there is also a vacancy research area of how lighting effects can be precisely controlled by engaging the instant real-time data-driven robot control and manipulating the material properties. Ceramics carries a wide range of transmittance and deformation potentials for robotics control with the research of its material property. This paper presents one semi-autonomous system that engages with real-time data-driven robotics control, hardware kit design, environmental building studies, human interaction, and exploratory research and experiments. Our objectives are to investigate the relationship between different clay bodies or ceramics’ physio-material properties and their transmittance; to explore the feedback system of instant lighting data in robotic fabrication to achieve precise lighting effect; to design the sufficient end effector and robot behaviors for different stages of deformation. We experiment with architectural clay, as the material of the façade that is potentially translucent at a certain stage can respond to light. Studying the relationship between form, material properties, and porosity can help create different interior and exterior light effects and provide façade solutions for specific architectural functions. The key idea is to maximize the utilization of in-progress robotics fabrication and ceramics materiality to create a highly integrated autonomous system for lighting facade design and manufacture.

Keywords: light transmittance, data-driven fabrication, computational design, computer vision, gamification for manufacturing

Procedia PDF Downloads 127

Authors: H. Ferfera-Harrar, T. Benhalima, D. Lerari

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Contamination of water, due to the discharge of untreated industrial wastewaters into the ecosystem, has become a serious problem for many countries. In this study, bioadsorbents based on chitosan-g-poly(acrylamide) and montmorillonite (MMt) clay (CTS-g-PAAm/MMt) hydrogel nanocomposites were prepared via free‐radical grafting copolymerization and crosslinking of acrylamide monomer (AAm) onto natural polysaccharide chitosan (CTS) as backbone, in presence of various contents of MMt clay as nanofiller. Then, they were hydrolyzed to obtain highly functionalized pH‐sensitive nanomaterials with uppermost swelling properties. Their structure characterization was conducted by X-Ray Diffraction (XRD) and Scanning Electron Microscopy (SEM) analyses. The adsorption performances of the developed nanohybrids were examined for removal of methylene blue (MB) cationic dye from aqueous solutions. The factors affecting the removal of MB, such as clay content, pH medium, adsorbent dose, initial dye concentration and temperature were explored. The adsorption process was found to be highly pH dependent. From adsorption kinetic results, the prepared adsorbents showed remarkable adsorption capacity and fast adsorption rate, mainly more than 88% of MB removal efficiency was reached after 50 min in 200 mg L^-1 of dye solution. In addition, the incorporating of various content of clay has enhanced adsorption capacity of CTS-g-PAAm matrix from 1685 to a highest value of 1749 mg g^-1 for the optimized nanocomposite containing 2 wt.% of MMt. The experimental kinetic data were well described by the pseudo-second-order model, while the equilibrium data were represented perfectly by Langmuir isotherm model. The maximum Langmuir equilibrium adsorption capacity (q_m) was found to increase from 2173 mg g⁻¹ until 2221 mg g⁻¹ by adding 2 wt.% of clay nanofiller. Thermodynamic parameters revealed the spontaneous and endothermic nature of the process. In addition, the reusability study revealed that these bioadsorbents could be well regenerated with desorption efficiency overhead 87% and without any obvious decrease of removal efficiency as compared to starting ones even after four consecutive adsorption/desorption cycles, which exceeded 64%. These results suggest that the optimized nanocomposites are promising as low cost bioadsorbents.

Keywords: chitosan, clay, dye adsorption, hydrogels nanocomposites

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Authors: Annalisa Gaetani, Anna Nora Tassetti, Gianna Fabi

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The hydroacoustic technology is an efficient tool to study the sea environment: the most recent advancement in artificial habitat mapping involves acoustic systems to investigate fish abundance, distribution and behavior in specific areas. Along with a detailed high-coverage bathymetric mapping of the seabed, the high-frequency Multibeam Echosounder (MBES) offers the potential of detecting fine-scale distribution of fish aggregation, combining its ability to detect at the same time the seafloor and the water column. Surveying fish schools distribution around artificial structures, MBES allows to evaluate how their presence modifies the biological natural habitat overtime in terms of fish attraction and abundance. In the last years, artificial habitat mapping experiences have been carried out by CNR-ISMAR in the Adriatic sea: fish assemblages aggregating at offshore gas platforms and artificial reefs have been systematically monitored employing different kinds of methodologies. This work focuses on two case studies: a gas extraction platform founded at 80 meters of depth in the central Adriatic sea, 30 miles far from the coast of Ancona, and the concrete and steel artificial reef of Senigallia, deployed by CNR-ISMAR about 1.2 miles offshore at a depth of 11.2 m . Relating the MBES data (metrical dimensions of fish assemblages, shape, depth, density etc.) with the results coming from other methodologies, such as experimental fishing surveys and underwater video camera, it has been possible to investigate the biological assemblage attracted by artificial structures hypothesizing which species populate the investigated area and their spatial dislocation from these artificial structures. Processing MBES bathymetric and water column data, 3D virtual scenes of the artificial habitats have been created, receiving an intuitive-looking depiction of their state and allowing overtime to evaluate their change in terms of dimensional characteristics and depth fish schools’ disposition. These MBES surveys play a leading part in the general multi-year programs carried out by CNR-ISMAR with the aim to assess potential biological changes linked to human activities on.

Keywords: artificial habitat mapping, fish assemblages, hydroacustic technology, multibeam echosounder

Procedia PDF Downloads 261

Authors: Sultan Samah A. Alenezi

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Many EFL teachers are eager to look into the best way to suit the needs of their students in EFL writing courses. Numerous studies suggest that online blogging may present a social interaction opportunity for EFL writing students. Additionally, it can foster peer collaboration and social support in the form of scaffolding, which, when viewed from the perspective of socio-cultural theory, can boost social support and foster the development of students' writing abilities. This idea is based on Vygotsky's theories, which emphasize how collaboration and social interaction facilitate effective learning. In Saudi Arabia, students are taught to write using conventional methods that are totally under the teacher's control. Without any peer contact or cooperation, students are spoon-fed in a passive environment. This study included the cognitive processes of the genre-process approach into the EFL writing classroom to facilitate the use of internet blogging in EFL writing education. Thirty second-year undergraduate students from the Department of Languages and Translation at a Saudi college participated in this study. This study employed an action research project that blended qualitative and quantitative methodologies to comprehend Saudi students' perceptions and experiences with internet blogging in an EFL process-genre writing classroom. It also looked at the advantages and challenges people faced when blogging. They included a poll, interviews, and blog postings made by students. The intervention's outcomes showed that merging genre-process procedures with blogging was a successful tactic, and the Saudi students' perceptions of this method of online blogging for EFL writing were quite positive. The socio-cultural theory constructs that Vygotsky advocates, such as scaffolding, collaboration, and social interaction, were also improved by blogging. These elements demonstrated the improvement in the students' written, reading, social, and collaborative thinking skills, as well as their positive attitudes toward English-language writing. But the students encountered a variety of problems that made blogging difficult for them. These problems ranged from technological ones, such sluggish internet connections, to learner inadequacies, like a lack of computer know-how and ineffective time management.

Keywords: blogging, process-gnere approach, saudi learenrs, writing quality

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Authors: Bertalan Jillek, Péter Szabó, Judit Kopniczky, István Szabó, Balázs Patczai, Kinga Turzó

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Hip and knee prostheses are one of the most frequently used medical implants, that can significantly improve patients’ quality of life. Long term success and biointegration of these prostheses depend on several factors, like bulk and surface characteristics, construction and biocompatibility of the material. The applied surgical technique, the general health condition and life-quality of the patient are also determinant factors. Medical devices used in orthopedic surgeries have different surfaces depending on their function inside the human body. Surface roughness of these implants determines the interaction with the surrounding tissues. Numerous modifications have been applied in the recent decades to improve a specific property of an implant. Our goal was to compare the surface characteristics of typical implant materials used in orthopedic surgery and traumatology. Morphological and chemical structure of Vortex plate anodized titanium, cemented THR (total hip replacement) stem high nitrogen REX steel (SS), uncemented THR stem and cup titanium (Ti) alloy with titanium plasma spray coating (TPS), cemented cup and uncemented acetabular liner HXL and UHMWPE and TKR (total knee replacement) femoral component CoCrMo alloy (Sanatmetal Ltd, Hungary) discs were examined. Visualization and elemental analysis were made by scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). Surface roughness was determined by atomic force microscopy (AFM) and profilometry. SEM and AFM revealed the morphological and roughness features of the examined materials. TPS Ti presented the highest Ra value (25 ± 2 μm, followed by CoCrMo alloy (535 ± 19 nm), Ti (227 ± 15 nm) and stainless steel (170 ± 11 nm). The roughness of the HXL and UHMWPE surfaces was in the same range, 147 ± 13 nm and 144 ± 15 nm, respectively. EDS confirmed typical elements on the investigated prosthesis materials: Vortex plate Ti (Ti, O, P); TPS Ti (Ti, O, Al); SS (Fe, Cr, Ni, C) CoCrMo (Co, Cr, Mo), HXL (C, Al, Ni) and UHMWPE (C, Al). The results indicate that the surface of prosthesis materials have significantly different features and the applied investigation methods are suitable for their characterization. Contact angle measurements and in vitro cell culture testing are further planned to test their surface energy characteristics and biocompatibility.

Keywords: morphology, PE, roughness, titanium

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Authors: Raluca-Ioana Antonescu

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The field research of the paper stands at the intersection between Linguistics and Sociology, while the problem of the research is the importance of language in the modernization process and in a globalized society. The research objective is to prove that language is a stimulant for modernity, while it defines the tradition and the culture of a specific society. In order to examine the linguistic change of the Korean language due to the modernity and globalization, the paper tries to answer one main question, What are the changes the Korean language underwent from a traditional version of Korean, towards one influenced by modernity?, and two secondary questions, How are explored in specialized literature the relations between globalization (and modernity) and culture (focusing on language)? and What influences the Korean language? For the purpose of answering the research questions, the paper has the main premise that due to modernity and globalization, the Korean language changed its discourse construction, and two secondary hypothesis, first is that in literature there are not much explored the relations between culture and modernity focusing on the language discourse construction, but more about identity issue and commodification problems, and the second hypothesis is that the Korean language is influenced by traditional values (like Confucianism) while receiving influence also of globalization process (especially from English language). In terms of methodology, the paper will analyze the two main influences upon the Korean language, referring to traditionalism (being defined as the influence of Confucianism) and modernism (as the influence of other countries’ language and culture), and how the Korean language it was constructed and modified due to these two elements. The paper will analyze at what level (grammatical, lexical, etc.) the traditionalism help at the construction of the Korean language, and what are the changes at each level that modernism brought along. As for the results of this research, the influence of modernism changed both lexically and grammatically the Korean language. In 60 years the increase of English influence is astonishing, and this paper shows the main changes the Korean language underwent, like the loanwords (Konglish), but also the reduction of the speech levels and the ease of the register variation use. Therefore the grammatical influence of modernity and globalization could be seen at the reduction of the speech level and register variation, while the lexical change comes with the influence of English language especially, where about 10% of the Korean vocabulary is considered to be loanwords. Also the paper presents the interrelation between traditionalism and modernity, with the example of Konglish, but not only (we can consider also the Korean greetings which are translated by Koreans when they speak in other languages, bringing their cultural characteristics in English discourse construction), which makes the Koreans global, since they speak in an international language, but still local since they cannot get rid completely of their culture.

Keywords: Confucianism, globalization, language and linguistic change, modernism, traditionalism

Procedia PDF Downloads 207

Authors: K. Sruthi, Sai Snehitha Yadavalli, Swathi Gosh Acharyya

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Water is the most crucial element for sustaining life on earth. Increasing water pollution directly or indirectly leads to harmful effects on human life. Most of the heavy metal ions are harmful in their cationic form. These heavy metal ions are released by various activities like disposing of batteries, industrial wastes, automobile emissions, and soil contamination. Ions like (Pb, Co, Cd) are carcinogenic and show many harmful effects when consumed more than certain limits proposed by WHO. The simultaneous detection of the heavy metal ions (Pb, Co, Cd), which are highly toxic, is reported in this study. There are many analytical methods for quantifying, but electrochemical techniques are given high priority because of their sensitivity and ability to detect and recognize lower concentrations. Square wave voltammetry was preferred in electrochemical methods due to the absence of background currents which is interference. Square wave voltammetry was performed on GCE for the quantitative detection of ions. Three electrode system consisting of a glassy carbon electrode as the working electrode (3 mm diameter), Ag/Agcl electrode as the reference electrode, and a platinum wire as the counter electrode was chosen for experimentation. The mechanism of detection was done by optimizing the experimental parameters, namely pH, scan rate, and temperature. Under the optimized conditions, square wave voltammetry was performed for simultaneous detection. Scan rates were varied from 5 mV/s to 100 mV/s and found that at 25 mV/s all the three ions were detected simultaneously with proper peaks at particular stripping potential. The variation of pH from 3 to 8 was done where the optimized pH was taken as pH 5 which holds good for three ions. There was a decreasing trend at starting because of hydrogen gas evolution, and after pH 5 again there was a decreasing trend that is because of hydroxide formation on the surface of the working electrode (GCE). The temperature variation from 25˚C to 45˚C was done where the optimum temperature concerning three ions was taken as 35˚C. Deposition and stripping potentials were given as +1.5 V and -1.5 V, and the resting time of 150 seconds was given. Three ions were detected at stripping potentials of Cd²⁺ at -0.84 V, Pb²⁺ at -0.54 V, and Co²⁺ at -0.44 V. The parameters of detection were optimized on a glassy carbon electrode for simultaneous detection of the ions at lower concentrations by square wave voltammetry.

Keywords: cadmium, cobalt, lead, glassy carbon electrode, square wave anodic stripping voltammetry

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Authors: Dohun Kim

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Technological innovations have stimulated flipped learning in many disciplines, including language teaching. It is a specific type of blended learning, which combines onsite (i.e. face-to-face) with online experiences to produce effective, efficient and flexible learning. Flipped learning literally ‘flips’ conventional teaching and learning activities upside down: it leverages technologies to deliver a lecture and direct instruction—other asynchronous activities as well—outside the classroom to reserve onsite time for interaction and activities in the upper cognitive realms: applying, analysing, evaluating and creating. Unlike the conventional flipped approaches, which focused on video lecture, followed by face-to-face or on-site session, new innovative methods incorporate various means and structures to serve the needs of different academic disciplines and classrooms. In the light of such innovations, this study adopted ‘student-engaged’ approaches to interpreter training and contrasts them with traditional classrooms. To this end, students were also encouraged to engage in asynchronous activities online, and innovative technologies, such as Telepresence, were employed. Based on the class implementation, a thorough examination was conducted to examine how we can structure and implement flipped classrooms for language and interpreting training while actively engaging learners. This study adopted a quantitative research method, while complementing it with a qualitative one. The key findings suggest that the significance of the instructor’s role does not dwindle, but his/her role changes to a moderator and a facilitator. Second, we can apply flipped learning to both theory- and practice-oriented modules. Third, students’ integration into the community of inquiry is of significant importance to foster active and higher-order learning. Fourth, cognitive presence and competence can be enhanced through strengthened and integrated teaching and social presences. Well-orchestrated teaching presence stimulates students to find out the problems and voices the convergences and divergences, while fluid social presence facilitates the exchanges of knowledge and the adjustment of solutions, which eventually contributes to consolidating cognitive presence—a key ingredient that enables the application and testing of the solutions and reflection thereon.

Keywords: blended learning, Community of Inquiry, flipped learning, interpreter training, student-centred learning

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Authors: Megan Weisbart

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Background/Significance: The Intensive Care Unit (ICU) environment contributes to nurse burnout. Burnout costs include decreased employee compassion, missed workdays, worse patient outcomes, diminished job performance, high turnover, and higher organizational cost. Meaningful recognition, nurturing of interpersonal connections, and mindfulness-based interventions are associated with decreased burnout. The purpose of this quality improvement project was to decrease Neonatal ICU (NICU) nurse burnout using a Wellness Bundle that fosters meaningful recognition, interpersonal connections and includes mindfulness-based interventions. Methods: The Professional Quality of Life Scale Version 5 (ProQOL5) was used to measure burnout before Wellness Bundle implementation, after six months, and will be given yearly for three years. Meaningful recognition bundle items include Online submission and posting of staff shoutouts, recognition events, Nurses Week and Unit Practice Council member gifts, and an employee recognition program. Fostering of interpersonal connections bundle items include: Monthly staff games with prizes, social events, raffle fundraisers, unit blog, unit wellness basket, and a wellness resource sheet. Quick coherence techniques were implemented at staff meetings and huddles as a mindfulness-based intervention. Findings: The mean baseline burnout score of 14 NICU nurses was 20.71 (low burnout). The baseline range was 13-28, with 11 nurses experiencing low burnout, three nurses experiencing moderate burnout, and zero nurses experiencing high burnout. After six months of the Wellness Bundle Implementation, the mean burnout score of 39 NICU nurses was 22.28 (low burnout). The range was 14-31, with 22 nurses experiencing low burnout, 17 nurses experiencing moderate burnout, and zero nurses experiencing high burnout. Conclusion: A NICU Wellness Bundle that incorporated meaningful recognition, fostering of interpersonal connections, and mindfulness-based activities was implemented to improve work environments and decrease nurse burnout. Participation bias and low baseline response rate may have affected the reliability of the data and necessitate another comparative measure of burnout in one year.

Keywords: burnout, NICU, nurse, wellness

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Authors: Abeer Heider

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This paper explores and classifies the different kinds of avoidances that students commonly make in the acquisition of Arabic as a second/foreign language, and suggests specific strategies to help students lessen their avoidance trends in hopes of streamlining the learning process. Students most commonly use avoidance strategies in grammar, and word choice. These different types of strategies have different implications and naturally require different approaches. Thus the question remains as to the most effective way to help students improve their Arabic, and how teachers can efficiently utilize these techniques. It is hoped that this research will contribute to understand the role of avoidance in the field of the second language acquisition in general, and as a type of input. Yet some researchers also note that similarity between L1 and L2 may be problematic as well since the learner may doubt that such similarity indeed exists and consequently avoid the identical constructions or elements (Jordens, 1977; Kellermann, 1977, 1978, 1986). In an effort to resolve this issue, a case study is being conducted. The present case study attempts to provide a broader analysis of what is acquired than is usually the case, analyzing the learners ‘accomplishments in terms of three –part framework of the components of communicative competence suggested by Michele Canale: grammatical competence, sociolinguistic competence and discourse competence. The subjects of this study are 15 students’ 22th year who came to study Arabic at Qatar University of Cairo. The 15 students are in the advanced level. They were complete intermediate level in Arabic when they arrive in Qatar for the first time. The study used discourse analytic method to examine how the first language affects students’ production and output in the second language, and how and when students use avoidance methods in their learning. The study will be conducted through Fall 2015 through analyzing audio recordings that are recorded throughout the entire semester. The recordings will be around 30 clips. The students are using supplementary listening and speaking materials. The group will be tested at the end of the term to assess any measurable difference between the techniques. Questionnaires will be administered to teachers and students before and after the semester to assess any change in attitude toward avoidance and selectivity methods. Responses to these questionnaires are analyzed and discussed to assess the relative merits of the aforementioned strategies to avoidance and selectivity to further support on. Implications and recommendations for teacher training are proposed.

Keywords: the second language acquisition, learning languages, selectivity, avoidance

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Authors: Vesta Kohlmeier, George C. Dragan, Juergen Orasche, Juergen Schnelle-Kreis, Dietmar Breuer, Ralf Zimmermann

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Aerosols from hazardous semi-volatile organic compounds (SVOC) may occur in workplace air and can simultaneously be found as particle and gas phase. For health risk assessment, it is necessary to collect particles and gases separately. This can be achieved by using a denuder for the gas phase collection, combined with a filter and an adsorber for particle collection. The study focused on the suitability of carbonaceous monolithic multi-channel denuders, so-called Novacarb™-Denuders (MastCarbon International Ltd., Guilford, UK), to achieve gas-particle separation. Particle transmission efficiency experiments were performed with polystyrene latex (PSL) particles (size range 0.51-3 µm), while the time dependent gas phase collection efficiency was analysed for polar and nonpolar SVOC (mass concentrations 7-10 mg/m3) over 2 h at 5 or 10 l/min. The experimental gas phase collection efficiency was also compared with theoretical predictions. For n-hexadecane (C16), the gas phase collection efficiency was max. 91 % for one denuder and max. 98 % for two denuders, while for diethylene glycol (DEG), a maximal gas phase collection efficiency of 93 % for one denuder and 97 % for two denuders was observed. At 5 l/min higher gas phase collection efficiencies were achieved than at 10 l/min. The deviations between the theoretical and experimental gas phase collection efficiencies were up to 5 % for C16 and 23 % for DEG. Since the theoretical efficiency depends on the geometric shape and length of the denuder, flow rate and diffusion coefficients of the tested substances, the obtained values define an upper limit which could be reached. Regarding the particle transmission through the denuders, the use of one denuder showed transmission efficiencies around 98 % for 1-3 µm particle diameters. The use of three denuders resulted in transmission efficiencies from 93-97 % for the same particle sizes. In summary, NovaCarb™-Denuders are well applicable for sampling aerosols of polar/nonpolar substances with particle diameters ≤3 µm and flow rates of 5 l/min or lower. These properties and their compact size make them suitable for use in personal aerosol samplers. This work is supported by the German Social Accident Insurance (DGUV), research contract FP371.

Keywords: gas phase collection efficiency, particle transmission, personal aerosol sampler, SVOC

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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: Seema Sant

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In the 21st century were four generation workforces are working, it’s crucial for organizations to build talent management strategy, as tech-savvy Gen Y has entered the work force. They are more connected to each other than ever – through the internet enabled Social media networks Social media has become important in today’s world. The users of such Social media sites have increased in multiple. From sharing their opinion for a brand/product to researching a company before going for an interview, making a conception about a company’s culture or following a Company’s updates due to sheer interest or for job vacancy, Work force today is constantly in touch with social networks. Thus corporate world has rightly realized its potential uses for business purpose. Companies now use social media for marketing, advertising, consumer survey, etc. For HR professionals, it is used for networking and connecting to the Talent pool- through Talent Community. Social recruiting is the process of sourcing or hiring candidates through the use of social sites such as LinkedIn, Facebook Twitter which provide them with an array of information about potential employee; this study represents an exploratory investigation on the role of social networking sites in recruitment. The primarily aim is to analyze the factors that can enhance the channel of recruitment used by of the recruiter with specific reference to the IT organizations in Mumbai, India. Particularly, the aim is to identify how and why companies use social media to attract and screen applicants during their recruitment processes. It also examines the advantages and limitations of recruitment through social media for employers. This is done by literature review. Further, the papers examine the recruiter impact and understand the various opportunities which have created due to technology, thus, to analyze and examine these factors, both primary, as well as secondary data, are collected for the study. The primary data are gathered from five HR manager working in five top IT organizations in Mumbai and 100 HR consultants’ i.e., recruiter. The data was collected by conducting a survey and supplying a closed-ended questionnaire. A comprehension analysis of the study is depicted through graphs and figures. From the analysis, it was observed that there exists a positive relationship between the level of employee recruited through social media and their organizational commitment. Finally the findings show that company’s i.e. recruiters are currently using social media in recruitment, but perhaps not as effective as they could be. The paper gives recommendations and conditions for success that can help employers to make the most out of social media in recruitment.

Keywords: recruitment, social media, social sites, workforce

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Authors: Shaohui Gong, Cheng Zhu, Yun Zhou, Weiming Zhang

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Low Earth Orbit (LEO) mega-constellations are poised to become crucial future infrastructure, providing dynamically configurable communication, navigation, remote sensing, and other services. The rapid deployment of these constellations has spurred an increasing focus on their regional service applications. This paper addresses this need by introducing a Payload Unit Service Capability Indicator (PUSCI), which quantifies the average service capacity that a single payload unit provides to a fixed-size ground area within the minimum service time, considering time, space, and performance dimensions. Using PUSCI, a framework is developed for evaluating the on-demand service capability of mega-constellations within specific regions. This framework divides the target region into Geographic Service Units (GSUs), defined by the size and shape of individual payload unit coverage. The method of employing time snapshots is used to determine satellite-ground coverage. PUSCI serves as the smallest unit of service acquisition for a GSU. By incorporating payload service rules, multi-satellite collaboration rules, and multi-satellite payload resource allocation rules, the framework assesses service demand satisfaction for each GSU, thereby evaluating overall regional service levels and fairness. This framework is applied to evaluate the on-demand service capability of regional communication services in mega-constellations, utilizing simulations to analyze key influencing factors. The results demonstrate that multi-satellite collaboration rules significantly impact regional service capability, with load-balancing strategies yielding superior performance. The multi-satellite payload resource allocation rules primarily affect service fairness, while GSU service demand is the main determinant of resource acquisition. Furthermore, the demands of neighboring GSUs influence service availability, highlighting the significant impact of ground demand distribution on overall mega-constellation performance. This PUSCI-based framework provides a quantitative tool for understanding and optimizing regional service capabilities in mega-constellations, offering substantial practical value.

Keywords: LEO mega-constellations, regional service, payload unit service capability indicator, capability evaluating, key influencing factors, simulations

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Authors: Mohan Bikram Thapa

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Despite the successful implementation of community forestry program, a number of pros and cons have been raised on Terai community forestry in the case of lowland locally called Terai region of Nepal, which climatically belongs to tropical humid and possessed high-quality forests in terms of ecology and economy. The study aims to investigate the local pricing strategy of forest products and its impacts on equitable forest benefits sharing, the collection of community fund and carrying out livelihood improvement activities. The study was carried out on six community forests revealed that local people have substantially benefited from the community forests. However, being the region is heterogeneous by socio-economic conditions and forest resources have higher economic potential, the decision of low pricing strategy made by the local people have created inequality problems while sharing the forest benefits, and poorly contributed to community fund collection and consequently carrying out limited activities of livelihood improvement. The paper argued that the decision of low pricing strategy of forest products is counterproductive to promote the equitable benefit-sharing in the areas of heterogeneous socio-economic conditions with high-value forests. The low pricing strategy has been increasing accessibility of better off households at a higher rate than poor, as such households always have the higher affording capacity. It is also defective to increase the community fund and carry out activities of livelihood improvement effectively. The study concluded that unilateral decentralized forest policy and decision-making autonomy to the local people seems questionable unless their decision-making capacities are enriched sufficiently. Therefore, it is recommended that empowerments of decision-making capacity of local people and their respective institutions together with policy and program formulation are prerequisite for efficient and equitable community forest management and its long-term sustainability.

Keywords: benefit sharing, community forest, livelihood, pricing mechanism, Nepal

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Authors: Yuvarani Naidu, Yasmeen Siddiqui, Mohd Yusof Rafii , Abu Seman Idris

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Sustainability of oil palm production in Southeast Asia, especially in Indonesia and Malaysia, is jeopardized by Ganoderma boninense, the fungus which causes basal stem rot (BSR) in oil palm. The root contact with unattended infected debris left in the plantations during replanting is known to be the primary source of inoculum. Abiding by the law, potentially effective technique of managing Ganoderma infected oil palm debris is deemed necessary because of the zero-burning policy in Malaysian oil palm plantations. White-rot hymenomycetes antagonistic to Ganoderma sp were selected to test their efficacy as log treatments in degrading Ganoderma infected oil palm logs and to minimize the survival of Ganoderma inoculum. Decay rate in terms of mass loss was significantly higher after the application of solid-state cultivation (SSC) of Trametes lactinea FBW (64% ±1.2), followed by Pycnoporus sanguineus FBR (55% ±1.7) in infected log block tissues, after 10 months of treatments. The degradation pattern was clearly distinguished between the treated and non-treated log blocks with the developed SSC formulations. The control infected log blocks showed the highest, whereas infected log blocks treated with either P. sanguineus FBR or T. lactinea FBW SSC formulations exhibited statistically lowest number of Ganoderma spp. recovery on Ganoderma Selective Medium (GSM), after 8 months of treatment. Out of that, the lowest recovery of Ganoderma spp. was reported in infected log blocks inoculated with the strain T. lactinea FBW (21% ± 0.9) followed by P. sanguineus FBR (33% ± 2.2), after 8 months, Further, no recovery of Ganoderma was noticeable, 10 months after treatment applications in log blocks treated with both of the formulations. This is the first nursery-base study to substantiate the initial colonization of white-rot hymenomycetes on oil palm log blocks previously infected with BSR pathogen, G. boninense. The present study has indicated that log blocks treatment with white-rot hymenomycetes significantly affected the mass loss of diseased and healthy log block tissues. This study provides a basis of biotechnological approaches inefficient degradation of oil palm-generated crop debris, under natural conditions with an ultimate aim of reducing the Ganoderma inoculum under heavy BSR infection pressure in eco-friendly manner.

Keywords: basal stem rot disease, ganoderma boninense, oil palm, white-rot fungi

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Authors: Preeti Verma, P. Chellapandi, N.C. Santhi Srinivas, Vakil Singh

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Modified 9Cr-1Mo steel is widely used for structural components like heat exchangers, pressure vessels and steam generator in the nuclear reactors. It is also found to be a candidate material for future metallic fuel sodium cooled fast breeder reactor because of its high thermal conductivity, lower thermal expansion coefficient, micro structural stability, high irradiation void swelling resistance and higher resistance to stress corrosion cracking in water-steam systems compared to austenitic stainless steels. The components of steam generators that operate at elevated temperatures are often subjected to repeated thermal stresses as a result of temperature gradients which occur on heating and cooling during start-ups and shutdowns or during variations in operating conditions of a reactor. These transient thermal stresses give rise to LCF damage. In the present investigation strain controlled low cycle fatigue tests were conducted at room temperature and 300 °C in normalized and tempered condition using total strain amplitudes in the range from ±0.25% to ±0.5% at strain rate of 10-2 s-1. Cyclic Stress response at high strain amplitudes (±0.31% to ±0.5%) showed initial softening followed by hardening upto a few cycles and subsequent softening till failure. The extent of softening increased with increase in strain amplitude and temperature. Depends on the strain amplitude of the test the stress strain hysteresis loops displayed Masing behaviour at higher strain amplitudes and non-Masing at lower strain amplitudes at both the temperatures. It is quite opposite to the usual Masing and Non-Masing behaviour reported earlier for different materials. Low cycle fatigue damage was evaluated in terms of plastic strain and plastic strain energy approach at room temperature and 300 °C. It was observed that the plastic strain energy approach was found to be more closely matches with the experimental fatigue lives particularly, at 300 °C where dynamic strain aging was observed.

Keywords: Modified 9Cr-mo steel, low cycle fatigue, Masing behavior, cyclic softening

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Authors: Tooba Aslam, Efthalia Chatzisymeon

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UV-assisted irradiation technologies are well-established for water and wastewater treatment. UVC treatments are widely used at large-scale, while UVA irradiation has more often been applied in combination with a catalyst (e.g. TiO₂ or FeSO₄) in smaller-scale systems. A technical issue of these systems is the formation of fouling on the quartz sleeves that houses the lamps. This fouling can prevent complete irradiation, therefore reducing the efficiency of the process. This paper investigates the effects of operational parameters, such as the type of wastewater, irradiation source, H₂O₂ addition, and water pH on fouling formation and, ultimately, the treatment of municipal wastewater. Batch experiments have been performed at lab-scale while monitoring water quality parameters including: COD, TS, TSS, TDS, temperature, pH, hardness, alkalinity, turbidity, TOC, UV transmission, UV₂₅₄ absorbance, and metal concentrations. The residence time of the wastewater in the reactor was 5 days in order to observe any fouling formation on the quartz surface. Over this period, it was observed that chemical oxygen demand (COD) decreased by 30% and 59% during photolysis (Ultraviolet A) and photo-catalysis (UVA/Fe/H₂O₂), respectively. Higher fouling formation was observed with iron-rich and phosphorous-rich wastewater. The highest rate of fouling was developed with phosphorous-rich wastewater, followed by the iron-rich wastewater. Photo-catalysis (UVA/Fe/H₂O₂) had better removal efficiency than photolysis (UVA). This was attributed to the Photo-Fenton reaction, which was initiated under these operational conditions. Scanning electron microscope (SEM) measurements of fouling formed on the quartz sleeves showed that particles vary in size, shape, and structure; some have more distinct structures and are generally larger and have less compact structure than the others. Energy-dispersive X-ray spectroscopy (EDX) results showed that the major metals present in the fouling cake were iron, phosphorous, and calcium. In conclusion, iron-rich wastewaters are more suitable for UV-assisted treatment since fouling formation on quartz sleeves can be minimized by the formation of oxidizing agents during treatment, such as hydroxyl radicals.

Keywords: advanced oxidation processes, photo-fenton treatment, photo-catalysis, wastewater treatment

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Authors: Peter J. Robinson, W. J. Wouter Botzen

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Individuals often over-weight low probabilities and under-weight moderate to high probabilities, however very low probabilities are either significantly over-weighted or neglected. Little is known about factors affecting probability weighting in Prospect Theory related to emotions specific to risk (anticipatory and anticipated emotions), the threshold of concern, as well as personality traits like locus of control. This study provides these insights by examining factors that influence probability weighting in the context of flood insurance demand in an economic experiment. In particular, we focus on determinants of flood probability neglect to provide recommendations for improved risk management. In addition, results obtained using real incentives and no performance-based payments are compared in the experiment with high experimental outcomes. Based on data collected from 1’041 Dutch homeowners, we find that: flood probability neglect is related to anticipated regret, worry and the threshold of concern. Moreover, locus of control and regret affect probabilistic pessimism. Nevertheless, we do not observe strong evidence that incentives influence flood probability neglect nor probability weighting. The results show that low, moderate and high flood probabilities are under-weighted, which is related to framing in the flooding context and the degree of realism respondents attach to high probability property damages. We suggest several policies to overcome psychological factors related to under-weighting flood probabilities to improve flood preparations. These include policies that promote better risk communication to enhance insurance decisions for individuals with a high threshold of concern, and education and information provision to change the behaviour of internal locus of control types as well as people who see insurance as an investment. Multi-year flood insurance may also prevent short-sighted behaviour of people who have a tendency to regret paying for insurance. Moreover, bundling low-probability/high-impact risks with more immediate risks may achieve an overall covered risk which is less likely to be judged as falling below thresholds of concern. These measures could aid the development of a flood insurance market in the Netherlands for which we find to be demand.

Keywords: flood insurance demand, prospect theory, risk perceptions, risk preferences

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Authors: Rajesh Karki, Safal Bhattarai, Saket Adhikari

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Reliable and economic operation of power systems are becoming extremely challenging with large scale integration of renewable energy sources due to the intermittency and uncertainty associated with renewable power generation. It is, therefore, important to make a quantitative risk assessment and explore the potential resources to mitigate such risks. Probabilistic models for different energy storage systems (ESS), such as the flywheel energy storage system (FESS) and the compressed air energy storage (CAES) incorporating specific charge/discharge performance and failure characteristics suitable for probabilistic risk assessment in power system operation and planning are presented in this paper. The proposed methodology used in FESS modelling offers flexibility to accommodate different configurations of plant topology. It is perceived that CAES has a high potential for grid-scale application, and a hybrid approach is proposed, which embeds a Monte-Carlo simulation (MCS) method in an analytical technique to develop a suitable reliability model of the CAES. The proposed ESS models are applied to a test system to investigate the economic and reliability benefits of the energy storage technologies in system operation and planning, as well as to assess their contributions in facilitating wind integration during different operating scenarios. A comparative study considering various storage system topologies are also presented. The impacts of failure rates of the critical components of ESS on the expected state of charge (SOC) and the performance of the different types of ESS during operation are illustrated with selected studies on the test system. The paper also applies the proposed models on the test system to investigate the economic and reliability benefits of the different ESS technologies and to evaluate their contributions in facilitating wind integration during different operating scenarios and system configurations. The conclusions drawn from the study results provide valuable information to help policymakers, system planners, and operators in arriving at effective and efficient policies, investment decisions, and operating strategies for planning and operation of power systems with large penetrations of renewable energy sources.

Keywords: flywheel energy storage, compressed air energy storage, power system reliability, renewable energy, system planning, system operation

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Authors: K. Frahtia, I. Mihoubi, S. Picot

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Leishmaniasis is a group of parasitic disease with a varied clinical expression caused by flagellate protozoa of the Leishmania genus. These diseases are transmitted to humans and animals by the sting of a vector insect, the female sandfly. Among the groups of dipteral disease vectors, Phlebotominae occupy a prime position and play a significant role in human pathology, such as leishmaniasis that affects nearly 350 million people worldwide. The vector control operation launched by health services throughout the country proves to be effective since despite the prevalence of the disease remains high especially in rural areas, leishmaniasis appears to be declining in Algeria. In this context, this study mainly concerns molecular detection of Leishmania from the vector. Furthermore, a molecular diagnosis has also been made on skin samples taken from patients in the region of Constantine, located in the North-East of Algeria. Concerning the vector, 5858 sandflies were captured, including 4360 males and 1498 females. Male specimens were identified based on their morphological. The morphological identification highlighted the presence of the Phlebotomus genus with a prevalence of 93% against 7% represented by the Sergentomyia genus. About the identified species, P. perniciosus is the most abundant with 59.4% of the male identified population followed by P. longicuspis with 24.7% of the workforce. P. perfiliewi is poorly represented by 6.7% of specimens followed by P. papatasi with 2.2% and 1.5% S. dreyfussi. Concerning skin samples, 45/79 (56.96%) collected samples were found positive by real-time PCR. This rate appears to be in sharp decline compared to previous years (alert peak of 30,227 cases in 2005). Concerning the detection of Leishmania from sandflies by RT-PCR, the results show that 3/60 PCR performed genus are positive with melting temperatures corresponding to that of the reference strain (84.1 +/- 0.4 ° C for L. infantum). This proves that the vectors were parasitized. On the other side, identification by RT-PCR species did not give any results. This could be explained by the presence of an insufficient amount of leishmanian DNA in the vector, and therefore support the hypothesis of the regression of leishmaniasis in Constantine.

Keywords: Algeria, molecular diagnostic, phlebotomus, real time PCR

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Authors: Torben Hansen, Lars Gronholdt, Alexander Josiassen, Anne Martensen

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Consumers often exhibit a bias in their knowledge; they often think that they know more or less than they do. The concept of 'knowledge over/underconfidence' (O/U) has in previous studies been used to investigate such knowledge bias. O/U appears as a combination of subjective and objective knowledge. Subjective knowledge relates to consumers’ perception of their knowledge, while objective knowledge relates to consumers’ absolute knowledge measured by objective standards. This separation leads to three scenarios: The consumer can either be knowledge calibrated (subjective and objective knowledge are similar), overconfident (subjective knowledge exceeds objective knowledge) or underconfident (objective knowledge exceeds subjective knowledge). Knowledge O/U is a highly useful concept in understanding consumer choice behavior. For example, knowledge overconfident individuals are likely to exaggerate their ability to make right choices, are more likely to opt out of necessary information search, spend less time to carry out a specific task than less knowledge confident consumers, and are more likely to show high financial trading volumes. Through the use of financial services as a case study, this study contributes to previous research by examining how consumer knowledge O/U affects two types of trust (broad-scope trust and narrow-scope trust) and consumer relationship satisfaction. Trust does not only concern consumer trust in individual companies (i.e., narrow.-scope confidence NST), but also concerns consumer confidence in the broader business context in which consumers plan and implement their behavior (i.e., broad scope trust, BST). NST is defined as "the expectation that the service provider can be relied on to deliver on its promises’, while BST is defined as ‘the expectation that companies within a particular business type can generally be relied on to deliver on their promises.’ This study expands our understanding of the interplay between consumer knowledge bias, consumer trust, and relationship marketing in two main ways: First, it is demonstrated that the more knowledge O/U a consumer becomes, the higher/lower NST and levels of relationship satisfaction will be. Second, it is demonstrated that BST has a negative moderating effect on the relationship between knowledge O/U and satisfaction, such that knowledge O/U has a higher positive/negative effect on relationship satisfaction when BST is low vs. high. The data for this study comprises 756 mutual fund investors. Trust is particularly important in consumers’ mutual fund behavior because mutual funds have important responsibilities in providing financial advice and in managing consumers’ funds.

Keywords: knowledge, cognitive bias, trust, customer-seller relationships, financial services

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Authors: Niloofar Zebarjad

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This research aims at finding a tool to provide basketball players with real-time audio feedback on their shooting form in free throw shots. Free throws played a pivotal role in taking the lead in fierce competitions. The major problem in performing an accurate free throw seems to be improper training. Since the arm movement during the free throw shot is complex, the coach or the athlete might miss the movement details during practice. Hence, there is a necessity to create a system that measures arm movements' critical characteristics and control for improper kinematics. The proposed setup in this study quantifies arm kinematics and provides real-time feedback as an audio signal consisting of a gyroscope sensor. Spatial shoulder angle data are transmitted in a mobile application in real-time and can be saved and processed for statistical and analysis purposes. The proposed system is easy to use, inexpensive, portable, and real-time applicable. Objectives: This research aims to modify and control the free throw using audio feedback and determine if and to what extent the new setup reduces errors in arm formations during throws and finally assesses the successful throw rate. Methods: One group of elite basketball athletes and two novice athletes (control and study group) participated in this study. Each group contains 5 participants being studied in three separate sessions over a week. Results: Empirical results showed enhancements in the free throw shooting style, shot pocket (SP), and locked position (LP). The mean values of shoulder angle were controlled on 25° and 45° for SP and LP, respectively, recommended by valid FIBA references. Conclusion: Throughout the experiments, the system helped correct and control the shoulder angles toward the targeted pattern of shot pocket (SP) and locked position (LP). According to the desired results for arm motion, adding another sensor to measure and control the elbow angle is recommended.

Keywords: audio-feedback, basketball, free-throw, locked-position, motor-control, shot-pocket

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Authors: Fedili Benamar, Belloulou Mohamed Lamine, Ouahes Hassane, Ghattas Samir

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Introduction: Perioperative blood loss is a frequent cause of complications in total hip replacement (THR). The present prospective study assessed the efficacy of tranexamic acid (Exacyl(®)) in reducing blood loss in primary THR. Hypothesis: Tranexamic acid reduces blood loss in THR. Material and method: -This is a prospective randomized study on the effectiveness of Exacyl (tranexamic acid) in total hip replacement surgery performed on a standardized technique between 2019 and September 2022. -It involved 154 patients, of which 84 received a single injection of Exacyl (group 1) at a dosage of 10 mg/kg over 20 minutes during the perioperative period. -All patients received postoperative thromboprophylaxis with enoxaparin 0.4 ml subcutaneously. -All patients were admitted to the post-interventional intensive care unit for a duration of 24 hours for monitoring and pain management as per the service protocol. Results: 154 patients, of which 84 received a single injection of Exacyl (group 1) and 70 patients patients who did not receive Exacyl perioperatively : (Group 2 ) The average age is 57 +/- 15 years The distribution by gender was nearly equal with 56% male and 44% female; "The distribution according to the ASA score was as follows: 20.2% ASA1, 82.3% ASA2, and 17.5% ASA3. "There was a significant difference in the average volume of intraoperative and postoperative bleeding during the 48 hours." The average bleeding volume for group 1 (received Exacyl) was 614 ml +/- 228, while the average bleeding volume for group 2 was 729 +/- 300, with a chi-square test of 6.35 and a p-value < 0.01, which is highly significant. The ANOVA test showed an F-statistic of 7.11 and a p-value of 0.008. A Bartlett test revealed a chi-square of 6.35 and a p-value < 0.01." "In Group 1 (patients who received Exacyl), 73% had bleeding less than 750 ml (Group A), and 26% had bleeding exceeding 750 ml (Group B). In Group 2 (patients who did not receive Exacyl perioperatively), 52% had bleeding less than 750 ml (Group A), and 47% had bleeding exceeding 750 ml (Group B). "Thus, the use of Exacyl reduced perioperative bleeding and specifically decreased the risk of severe bleeding exceeding 750 ml by 43% with a relative risk (RR) of 1.37 and a p-value < 0.01. The transfusion rate was 1.19% in the population of Group 1 (Exacyl), whereas it was 10% in the population of Group 2 (no Exacyl). It can be stated that the use of Exacyl resulted in a reduction in perioperative blood transfusion with an RR of 0.1 and a p-value of 0.02. Conclusions: The use of Exacyl significantly reduced perioperative bleeding in this type of surgery.

Keywords: acid tranexamic, blood loss, anesthesia, total hip replacement, surgery

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Authors: Hussein S. Elkuwafi

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Evaluation of cathodic protection systems using sacrificial zinc and magnesium electrodes is critical to ensuring the longevity and structural integrity of large reinforced concrete pipes spanning more than 2,000 km. This study focuses on evaluating these systems using near-interval potential survey (CIPS) techniques and over a 25-year installation period. Comparing these tests with international standards and assessing the extent to which these standards are met is crucial for ensuring the effectiveness and reliability of the cathodic protection system. This comparison allows for the identification of any discrepancies and ensures that the system adheres to globally recognized benchmarks, thereby enhancing the overall protection and longevity of the infrastructure. Cathodic protection is necessary to reduce corrosion, which poses a major threat to the durability of concrete pipes. Sacrificial zinc and magnesium electrodes are used due to their effectiveness in providing a protective layer against corrosive elements. Additionally, it is important to compare cases of pipe failures and their causes, particularly those not related to corrosion. Factors such as external loads, internal pressures, water velocity, clogging, ground movement, and extreme temperatures can all contribute to pipe failures. By understanding these non-corrosion-related causes, we can develop more comprehensive protection strategies and improve the overall resilience of the pipeline system. The CIPS method allows for precise monitoring of the protection levels along the extensive pipeline, identifying areas of potential vulnerability and ensuring uniform protection. The results indicate that the use of sacrificial electrodes significantly reduces the rate of corrosion, thereby extending the service life of the infrastructure. This evaluation underscores the importance of regular monitoring and maintenance of cathodic protection systems to prevent costly repairs and ensure the safe operation of critical infrastructure. The findings contribute to the optimization of cathodic protection strategies, enhancing the reliability and sustainability of large-scale pipeline projects.

Keywords: cathodic protection, sacrificial anodes, reinforced concrete pipes, corrosion prevention

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Authors: Rehin Sulay, Anandhu Krishna, Jintumol Mathew, Vibin Ipe Thomas

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N-Nitrosodimethyl amine, the simplest member of the N-Nitrosoamine family, is a carcinogenic and mutagenic agent that has gained considerable research interest owing to its toxic nature. Ozonation of industrially important hydrazines such as unsymmetrical dimethylhydrazine (UDMH) or monomethylhydrazine (MMH) has been associated with NDMA formation and accumulation in the environment. UDMH/MMH - ozonation also leads to several other transformation products such as acetaldehyde dimethyl hydrazone (ADMH), tetramethyl tetra azene (TMT), diazomethane, methyl diazene, etc, which can be either precursors or competitors for NDMA formation.In this work, we explored the formation mechanism of ADMH and TMT from UDMH-ozonation and their further oxidation to NDMA using the second-order Moller Plesset perturbation theory employing the 6-311G(d) basis set. We have also investigated how MMH selectively forms methyl diazene and diazomethane under normal conditions and NDMA in the presence of excess ozone. Our calculations indicate that the reactions proceed via an initial H abstraction from the hydrazine –NH2 group followed by the oxidation of the generated N-radical species. The formation of ADMH from the UDMH-ozone reaction involves an acetaldehyde intermediate, which then reacts with a second UDMH molecule to generate ADMH. The preferable attack of ozone molecule on N=C bond of ADMH generates DMAN intermediate, which subsequently undergoes oxidation to form NDMA. Unlike other transformation products, TMT formation occurs via the dimerization of DMAN. Though there exist a N=N bonds in the TMT, which are preferable attacking sites for ozone, experimental studies show the lower yields of NDMA formation, which corroborates with the high activation barrier required for the process(42kcal/mol).Overall, our calculated results agree well with the experimental observations and rate constants. Computational calculations bring insights into the electronic nature and kinetics of the elementary reactions of this pathway, enabled by computed energies of structures that are not possible to access experimentally.

Keywords: reaction mechanism, ozonation, substituted hydrazine, transition state

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Authors: Miroslav Dumbrovsky

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The paper deals with impacts of climate change with the main emphasis on land degradation, agriculture and forestry management in the landscape. Land degradation, due to adverse effect of farmers activities, as a result of inappropriate conventional technologies, was a major issue in the Czech Republic during the 20th century and will remain for solving in the 21st century. The importance of land degradation is very high because of its impact on crop productivity and many other adverse effects. Land degradation through soil degradation is causing losses on crop productivity and quality of the environment, through decreasing quality of soil and water (especially water resources). Negative effects of conventional farming practices are increased water erosion, as well as crusting and compaction of the topsoil and subsoil. Soil erosion caused by water destructs the soil’s structure, reduces crop productivity due to deterioration in soil physical and chemical properties such as infiltration rate, water-holding capacity, loss of nutrients needed for crop production, and loss of soil carbon. Water erosion occurs on fields with row crops (maize, sunflower), especially during the rainfall period from April to October. Recently there is a serious problem of greatly expanded production of biofuels and bioenergy from field crops. The result is accelerated soil degradation. The damages (on and off- site) are greater than the benefits. An effective soil conservation requires an appropriate complex system of measures in the landscape. They are also important to continue to develop new sophisticated methods and technologies for decreasing land degradation. The system of soil conservation solving land degradation depend on the ability and the willingness of land users to apply them. When we talk about land degradation, it is not just a technical issue but also an economic and political issue. From a technical point of view, we have already made many positive steps, but for successful solving the problem of land degradation is necessary to develop suitable economic and political tools to increase the willingness and ability of land users to adopt conservation measures.

Keywords: land degradation, soil erosion, soil conservation, climate change

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Authors: Marlene Rosa, Susana Lopes

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Board games have been used for different purposes in geriatric care, demonstrating good results for health in general. However, there is not a conceptual framework that can help professionals and researchers in this area to design intervention programs or to think about future studies in this area. The aim of this study was to provide a pilot collection of board games’ serious purposes in geriatric care, using a WHO framework for health and disability. Study cases were developed in seven geriatric residential institutions from the center region in Portugal that are included in AGILAB program. The AGILAB program is a serious game-based method to train and spread out the implementation of board games in geriatric care. Each institution provides 2-hours/week of experiences using TATI Hand Game for serious purposes and then fulfill questions about a study-case (player characteristics; explain changes in players health according to this game experience). Two independent researchers read the information and classified it according to the International Classification for Functioning and Disability (ICF) categories. Any discrepancy was solved in a consensus meeting. Results indicate an important variability in body functions and structures: specific mental functions (e.g., b140 Attention functions, b144 Memory functions), b156 Perceptual functions, b2 sensory functions and pain (e.g., b230 Hearing functions; b265 Touch function; b280 Sensation of pain), b7 neuromusculoskeletal and movement-related functions (e.g., b730 Muscle power functions; b760 Control of voluntary movement functions; b710 Mobility of joint functions). Less variability was found in activities and participation domains, such as purposeful sensory experiences (d110-d129) (e.g., d115 Listening), communication (d3), d710 basic interpersonal interactions, d920 recreation and leisure (d9200 Play; d9205 Socializing). Concluding, this framework designed from a brief gamed-based experience includes mental, perceptual, sensory, neuromusculoskeletal, and movement-related functions and participation in sensory, communication, and leisure domains. More studies, including different experiences and a high number of users, should be developed to provide a more comprehensive ICF framework for game-based experiences in geriatric care.

Keywords: board game, aging, framework, experience

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Authors: Pawel Albrycht, Monika Ksiezopolska-Gocalska, Robert Holyst

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Surface Enhanced Raman Spectroscopy (SERS) is a technique of growing importance not only in purely scientific research related to analytical chemistry. It finds more and more applications in broadly understood testing - medical, forensic, pharmaceutical, food - and everywhere works perfectly, on one condition that SERS substrates used for testing give adequate enhancement, repeatability, and homogeneity of SERS signal. This is a problem that has existed since the invention of this technique. Some laboratories use as SERS amplifiers colloids with silver or gold nanoparticles, others form rough silver or gold surfaces, but results are generally either weak or unrepeatable. Furthermore, these structures are very often highly specific - they amplify the signal only of a small group of compounds. It means that they work with some kinds of analytes but only with those which were used at a developer’s laboratory. When it comes to research on different compounds, completely new SERS 'substrates' are required. That underlay our decision to develop universal substrates for the SERS spectroscopy. Generally, each compound has different affinity for both silver and gold, which have the best SERS properties, and that's what depends on what signal we get in the SERS spectrum. Our task was to create the platform that gives a characteristic 'fingerprint' of the largest number of compounds with very high repeatability - even at the expense of the intensity of the enhancement factor (EF) (possibility to repeat research results is of the uttermost importance). As specified above SERS substrates are offered by SERSitive company. Applied method is based on cyclic potentiodynamic electrodeposition of silver or silver-gold nanoparticles on the conductive surface of ITO-coated glass at controlled temperature of the reaction solution. Silver nanoparticles are supplied in the form of silver nitrate (AgNO₃, 10 mM), gold nanoparticles are derived from tetrachloroauric acid (10 mM) while sodium sulfite (Na₂O₃, 5 mM) is used as a reductor. To limit and standardize the size of the SERS surface on which nanoparticles are deposited, photolithography is used. We secure the desired ITO-coated glass surface, and then etch the unprotected ITO layer which prevents nanoparticles from settling at these sites. On the prepared surface, we carry out the process described above, obtaining SERS surface with nanoparticles of sizes 50-400 nm. The SERSitive platforms present highly sensitivity (EF = 10⁵-10⁶), homogeneity and repeatability (70-80%).

Keywords: electrodeposition, nanoparticles, Raman spectroscopy, SERS, SERSitive, SERS platforms, SERS substrates

Procedia PDF Downloads 159