Search results for: acid media

Authors: Yuriko Takayama, Norihiro Kato

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Quorum sensing (QS) is a cell-to-cell communication system in bacteria to regulate expression of target genes. In gram-negative bacteria, activation on QS is controlled by a concentration increase of N-acylhomoserine lactone (AHL), which can diffuse in and out of the cell. Effective control of QS is expected to avoid virulence factor production in infectious pathogens, biofilm formation, and antibiotic production because various cell functions in gram-negative bacteria are controlled by AHL-mediated QS. In this research, we applied cyclodextrins (CDs) as artificial hosts for the AHL signal to reduce the AHL concentration in the culture broth below its threshold for QS activation. The AHL-receptor complex induced under the high AHL concentration activates transcription of the QS-target gene. Accordingly, artificial reduction of the AHL concentration is one of the effective strategies to inhibit the QS. A hydrophobic cavity of the CD can interact with the acyl-chain of the AHL due to hydrophobic interaction in aqueous media. We studied N-hexanoylhomoserine lactone (C6HSL)-mediated QS in Serratia marcescens; accumulation of C6HSL is responsible for regulation of the expression of pig cluster. Inhibitory effects of added CDs on QS were demonstrated by determination of prodigiosin amount inside cells after reaching stationary phase, because production of prodigiosin depends on the C6HSL-mediated QS. By adding approximately 6 wt% hydroxypropyl-β-CD (HP-β-CD) in Luria-Bertani (LB) medium prior to inoculation of S. maecescens AS-1, the intracellularly accumulated prodigiosin was drastically reduced to 7-10%, which was determined after the extraction of prodigiosin in acidified ethanol. The AHL retention ability of HP-β-CD was also demonstrated by Chromobacterium violacuem CV026 bioassay. The CV026 strain is an AHL-synthase defective mutant that activates QS solely by adding AHLs from outside of cells. A purple pigment violacein is induced by activation of the AHL-mediated QS. We demonstrated that the violacein production was effectively suppressed when the C6HSL standard solution was spotted on a LB agar plate dispersing CV026 cells and HP-β-CD. Physico-chemical analysis was performed to study the affinity between the immobilized CD and added C6HSL using a quartz crystal microbalance (QCM) sensor. The COOH-terminated self-assembled monolayer was prepared on a gold electrode of 27-MHz AT-cut quartz crystal. Mono(6-deoxy-6-N, N-diethylamino)-β-CD was immobilized on the electrode using water-soluble carbodiimide. The C6HSL interaction with the β-CD cavity was studied by injecting the C6HSL solution to a cup-type sensor cell filled with buffer solution. A decrement of resonant frequency (ΔFs) clearly showed the effective C6HSL complexation with immobilized β-CD and its stability constant for MBP-SpnR-C6HSL complex was on the order of 102 M-1. The CD has high potential for engineered control of QS because it is safe for human use.

Keywords: acylhomoserine lactone, cyclodextrin, intracellular signaling, quorum sensing

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Authors: Takahiro Nishimura, Kouki Doi, Hiroshi Fujimoto

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Touch-sensitive screens that serve as displays and input devices have been adopted in many portable terminals such as smartphones and personal media players, and the market of touch-sensitive screens has expanded greatly. One of the advantages of touch-sensitive screen is the flexibility in the graphical user interface (GUI) design, and it is imperative to design an appropriate GUI to realize an easy-to-use interface. Moreover, it is important to evaluate the relationship between pointing performance and GUI design. There is much knowledge regarding easy-to-use GUI designs for portable terminals with touch-sensitive screens, and most have focused on GUI design approaches for women or children with small hands. In contrast, GUI design approaches for users with large hands have not received sufficient attention. In this study, to obtain knowledge that contributes to the establishment of individualized easy-to-use GUI design guidelines, we conducted experiments to investigate the relationship between thumb length and pointing performance on portable terminals with touch-sensitive screens. In this study, fourteen college students who participated in the experiment were divided into two groups based on the length of their thumbs. Specifically, we categorized the participants into two groups, thumbs longer than 64.2 mm into L (Long) group, and thumbs longer than 57.4 mm but shorter than 64.2 mm into A (Average) group, based on Japanese anthropometric database. They took part in this study under the authorization of Waseda University’s ‘Ethics Review Committee on Research with Human Subjects’. We created an application for the experimental task and implemented it on the projected capacitive touch-sensitive screen portable terminal (iPod touch (4th generation)). The display size was 3.5 inch and 960 × 640 - pixel resolution at 326 ppi (pixels per inch). This terminal was selected as the experimental device, because of its wide use and market share. The operational procedure of the application is as follows. First, the participants placed their thumb on the start position. Then, one cross-shaped target in a 10 × 7 array of 70 positions appeared at random. The participants pointed the target with their thumb as accurately and as fast as possible. Then, they returned their thumb to the start position and waited. The operation ended when this procedure had been repeated until all 70 targets had each been pointed at once by the participants. We adopted the evaluation indices for absolute error, variable error, and pointing time to investigate pointing performance when using the portable terminal. The results showed that pointing performance varied with thumb length. In particular, on the lower right side of the screen, the performance of L group with long thumb was low. Further, we presented an approach for designing easy-to- use button GUI for users with long thumbs. The contributions of this study include revelation of the relationship between pointing performance and user’s thumb length when using a portable terminal in terms of accuracy, precision, and speed of pointing. We hope that these findings contribute to an easy-to-use GUI design for users with large hands.

Keywords: pointing performance, portable terminal, thumb length, touch-sensitive screen

Procedia PDF Downloads 140

Authors: Avi Shrivastava

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In 2021, two heart-wrenching scenes, shown live on television screens across countries, painted a grim picture of refugees. One of them was of people clinging onto an airplane's wings in their desperate attempt to flee war-torn Afghanistan. They ultimately fell to their death. The other scene was the U.S. government authorities separating children from their parents or guardians to deter migrants/refugees from coming to the U.S. These events show the desperation refugees feel when they are trying to leave their homes in disaster zones. However, data paints a grave picture of the current refugee situation. It also indicates that a bleak future lies ahead for the refugees across the globe. Data and information are the two threads that intertwine to weave the shimmery fabric of modern society. Data and information are often used interchangeably, but they differ considerably. For example, information analysis reveals rationale, and logic, while data analysis, on the other hand, reveals a pattern. Moreover, patterns revealed by data can enable us to create the necessary tools to combat huge problems on our hands. Data analysis paints a clear picture so that the decision-making process becomes simple. Geopolitical and economic data can be used to predict future refugee hotspots. Accurately predicting the next refugee hotspots will allow governments and relief agencies to prepare better for future refugee crises. The refugee crisis does not have binary answers. Given the emotionally wrenching nature of the ground realities, experts often shy away from realistically stating things as they are. This hesitancy can cost lives. When decisions are based solely on data, emotions can be removed from the decision-making process. Data also presents irrefutable evidence and tells whether there is a solution or not. Moreover, it also responds to a nonbinary crisis with a binary answer. Because of all that, it becomes easier to tackle a problem. Data science and A.I. can predict future refugee crises. With the recent explosion of data due to the rise of social media platforms, data and insight into data has solved many social and political problems. Data science can also help solve many issues refugees face while staying in refugee camps or adopted countries. This paper looks into various ways data science can help solve refugee problems. A.I.-based chatbots can help refugees seek legal help to find asylum in the country they want to settle in. These chatbots can help them find a marketplace where they can find help from the people willing to help. Data science and technology can also help solve refugees' many problems, including food, shelter, employment, security, and assimilation. The refugee problem seems to be one of the most challenging for social and political reasons. Data science and machine learning can help prevent the refugee crisis and solve or alleviate some of the problems that refugees face in their journey to a better life. With the explosion of data in the last decade, data science has made it possible to solve many geopolitical and social issues.

Keywords: refugee crisis, artificial intelligence, data science, refugee camps, Afghanistan, Ukraine

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Authors: I. Derek Kaka’an, P. Smolianov, D. Koh Choon Lian, S. Dion, C. Schoen, J. Norberg

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This study was designed to examine mass participation and elite football performance in Nigeria with reference to advance international football management practices. Over 200 sources of literature on sport delivery systems were analyzed to construct a globally applicable model of elite football integrated with mass participation, comprising of the following three levels: macro- (socio-economic, cultural, legislative, and organizational), meso- (infrastructures, personnel, and services enabling sport programs) and micro-level (operations, processes, and methodologies for development of individual athletes). The model has received scholarly validation and showed to be a framework for program analysis that is not culturally bound. The Smolianov and Zakus model has been employed for further understanding of sport systems such as US soccer, US Rugby, swimming, tennis, and volleyball as well as Russian and Dutch swimming. A questionnaire was developed using the above-mentioned model. Survey questions were validated by 12 experts including academicians, executives from sport governing bodies, football coaches, and administrators. To identify best practices and determine areas for improvement of football in Nigeria, 120 coaches completed the questionnaire. Useful exemplars and possible improvements were further identified through semi-structured discussions with 10 Nigerian football administrators and experts. Finally, content analysis of Nigeria Football Federation’s website and organizational documentation was conducted. This paper focuses on the meso-level of Nigerian football delivery, particularly infrastructures, personnel, and services enabling sport programs. This includes training centers, competition systems, and intellectual services. Results identified remarkable achievements coupled with great potential to further develop football in different types of public and private organizations in Nigeria. These include: assimilating football competitions with other cultural and educational activities, providing favorable conditions for employees of all possible organizations to partake and help in managing football programs and events, providing football coaching integrated with counseling for prevention of antisocial conduct, and improving cooperation between football programs and organizations for peace-making and advancement of international relations, tourism, and socio-economic development. Accurate reporting of the sports programs from the media should be encouraged through staff training for better awareness of various events. The systematic integration of these meso-level practices into the balanced development of mass and high-performance football will contribute to international sport success as well as national health, education, and social harmony.

Keywords: football, high performance, mass participation, Nigeria, sport development

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Authors: Palita Sooksamran, Katcharin Mahawong

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This research aims to offer the development of innovator teachers training curriculum to create instructional innovation according to active learning approach to enhance learning achievement. The research and development process is carried out in 3 steps: Step 1 The study of the needs necessary to develop a training curriculum: the inquiry was conducted by a sample of teachers in private schools in Phayao province that provide basic education at the level of education. Using a questionnaire of 176 people, the sample was defined using a table of random numbers and stratified samples, using the school as a random layer. Step 2 Training curriculum development: the tools used are developed training curriculum and curriculum assessments, with nine experts checking the appropriateness of the draft curriculum. The statistic used in data analysis is the average ( ) and standard deviation (S.D.) Step 3 study on effectiveness of training curriculum: one group pretest/posttest design applied in this study. The sample consisted of 35 teachers from private schools in Phayao province. The participants volunteered to attend on their own. The results of the research showed that: 1.The essential demand index needed with the list of essential needs in descending order is the choice and create of multimedia media, videos, application for learning management at the highest level ,Developed of multimedia, video and applications for learning management and selection of innovative learning management techniques and methods of solve the problem Learning , respectively. 2. The components of the training curriculum include principles, aims, scope of content, training activities, learning materials and resources, supervision evaluation. The scope of the curriculum consists of basic knowledge about learning management innovation, active learning, lesson plan design, learning materials and resources, learning measurement and evaluation, implementation of lesson plans into classroom and supervision and motoring. The results of the evaluation of quality of the draft training curriculum at the highest level. The Experts suggestion is that the purpose of the course should be used words that convey the results. 3. The effectiveness of training curriculum 1) Cognitive outcomes of the teachers in creating innovative learning management was at a high level of relative gain score. 2) The assessment results of learning management ability according to the active learning approach to enhance learning achievement by assessing from 2 education supervisor as a whole were very high , 3) Quality of innovation learning management based on active learning approach to enhance learning achievement of the teachers, 7 instructional Innovations were evaluated as outstanding works and 26 instructional Innovations passed the standard 4) Overall learning achievement of students who learned from 35 the sample teachers was at a high level of relative gain score 5) teachers' satisfaction towards the training curriculum was at the highest level.

Keywords: training curriculum, innovator teachers, active learning approach, learning achievement

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Authors: Abdulaziz Bashir Kutawa1, 2, *, Khairulmazmi Ahmad 1, 3, Mohd Zobir Hussein 4, Asgar Ali 5, * Mohd Aswad Abdul Wahab1, Amara Rafi3, Mahesh Tiran Gunasena1, 6, Muhammad Ziaur Rahman1, 7, Md Imam Hossain1, And Syazwan Afif Mohd Zobir1

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Various abiotic and biotic stresses have an impact on rice production all around the world. The most serious and prevalent disease in rice plants, known as rice blast, is one of the major obstacles to the production of rice. It is one of the diseases that has the greatest negative effects on rice farming globally, the disease is caused by a fungus called Magnaporthe grisae. Since nanoparticles were shown to have an inhibitory impact on certain types of fungus, nanotechnology is a novel notion to enhance agriculture by battling plant diseases. Utilizing nanocarrier systems enables the active chemicals to be absorbed, attached, and encapsulated to produce efficient nanodelivery formulations. The objectives of this research work were to determine the efficacy and mode of action of the nanofungicides (in-vitro) and in field conditions (in-vivo). Ionic gelation method was used in the development of the nanofungicides. Using the poisoned media method, the synthesized agronanofungicides' in-vitro antifungal activity was assessed against M. grisae. The potato dextrose agar (PDA) was amended in several concentrations; 0.001, 0.005, 0.01, 0.025, 0.05, 0.1, 0.15, 0.20, 0.25, 0.30, and 0.35 ppm for the nanofungicides. Medium with the only solvent served as a control. Every day, mycelial growth was measured, and PIRG (percentage inhibition of radial growth) was also computed. Every day, mycelial growth was measured, and PIRG (percentage inhibition of radial growth) was also computed. Based on the results of the zone of inhibition, the chitosan-hexaconazole agronanofungicide (2g/mL) was the most effective fungicide to inhibit the growth of the fungus with 100% inhibition at 0.2, 0.25, 0.30, and 0.35 ppm, respectively. Then followed by carbendazim analytical fungicide that inhibited the growth of the fungus (100%) at 5, 10, 25, 50, and 100 ppm, respectively. The least were found to be propiconazole and basamid fungicides with 100% inhibition only at 100 ppm. The scanning electron microscope (SEM), confocal laser scanning microscope (CLSM), and transmission electron microscope (TEM) were used to study the mechanisms of action of the M. grisae fungal cells. The results showed that both carbendazim, chitosan-hexaconazole, and HXE were found to be the most effective fungicides in disrupting the mycelia of the fungus, and internal structures of the fungal cells. The results of the field assessment showed that the CHDEN treatment (5g/L, double dosage) was found to be the most effective fungicide to reduce the intensity of the rice blast disease with DSI of 17.56%, lesion length (0.43 cm), DR of 82.44%, AUDPC of 260.54 Unit2, and PI of 65.33%, respectively. The least treatment was found to be chitosan-hexaconazole-dazomet (2.5g/L, MIC). The usage of CHDEN and CHEN nanofungicides will significantly assist in lessening the severity of rice blast in the fields, increasing output and profit for rice farmers.

Keywords: chitosan, hexaconazole, disease incidence, and magnaporthe grisae

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Authors: Nutthan Inkhong, Sutthiphong Ruangchante

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Chiang Rai province is located at the northern border of Thailand. Most of the geography there is the northern continental highlands, and the population has many types of inhabitants, including Thai people, immigrants and ethnic groups such as Akha, Lahu, Lisu, Yao, etc. Most of these ethnic groups migrated from neighbouring countries such as Myanmar, Laos, China, etc. and settled in the mountains. Each ethnic group has their unique traditions, culture, and ways of life, including the musical culture that the ancestors of each ethnic group brought with them. In the present, the Akha have the largest population in the region and still live together in numerous villages in many districts. Thus, Akha musical culture still appears in the community traditions and cultural events of Chiang Rai province regularly. This article presents the situations of Akha musical culture in the present and the predictions for the future. The study method involves the analysis of music information and the related social contexts, which were collected from the fieldwork of ethnomusicological methodology by in-depth interviews, observations, audio and visual recordings, and related documents. The results found that the important persons who are related with Akha musical culture include (1) a musical instrument maker (lives in Mae Chan district) who produces various Akha musical instruments, including gourd mouth organs, Akha drums, two-way flutes, three-hole flutes, Jew’s harps (the sound of teenage love), buffalo horns (the sound symbol of hunting) and bird call instruments (the imitation of bird sounds), (2) a folk philosopher (lives in Mae Pha Luang district) who can teach music to the new generation of Akha people as well as lecture and demonstrate music to academics and tourists, and (3) a community leader (lives in Mae Chan district) who conserves Akha performances, singing and music through various activities of the students in an informal school. Because of the changes to the social contexts and ways of life of the Akha people, such as the educational system, religion, social media, etc., including the popularity of both Thai and international popular music among the new generation of Akha people, changes to and the fading away of Akha musical culture in the future may likely occur. Therefore, the conservation and inheritance of Akha music is an issue that should be resolved quickly. This primary study leads to the next step of the ethnomusicological work and plays a part in preventing or reducing the problems impacting Akha musical culture survival by the recording of Akha music in all of its dimensions, such as producing musical instruments, playing musical instruments, analysis of tuning systems, recording Akha music as musical notation using symbols, researching related social contexts, etc. and the transcription of this information to create lessons that can be returned to the Akha community.

Keywords: Akha music, Chiang Rai, ethnic music in Thailand, ethnomusicology

Procedia PDF Downloads 129

Authors: Afolabi K. Esther, Kuye Tolulope, Babafemi, L. Olayemi, Omikunle Yemisi

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Background: Cervical cancer is a potentially preventable disease of public significance. All sexually active women are at risk of cervical cancer; however, the uptake and coverage are low in low-middle resource countries. Hence, the programme explored the feasibility of demonstrating an innovative and low-cost system approach to cervical cancer screening service delivery among reproductive-aged women in low–resource settings in Southwestern Nigeria. This was to promote the uptake and quality improvement of cervical cancer screening services. Methods: This study was an intervention project in three senatorial districts in Osun State that have primary, secondary and tertiary health facilities. The project was in three phases; Pre-intervention, Intervention, and Post-intervention. The study utilised the existing infrastructure, facilities and staff in project settings. The study population was nurse-midwives, community health workers and reproductive-aged women (30-49 years). The intervention phase entailed using innovative, culturally appropriate strategies to create awareness of cervical cancer and preventive health-seeking behaviour among women in the reproductive-aged group (30-49) years. Also, the service providers (community health workers, Nurses, and Midwives) were trained on screening methods and treatment of pre-cancerous lesions, and there was the provision of essential equipment and supplies for cervical cancer screening services at health facilities. Besides, advocacy and engagement were made with relevant stakeholders to integrate the cervical cancer screening services into related reproductive health services and greater allocation of resources. The expected results compared the pre and post-intervention using the baseline and process indicators and the effect of the intervention phase on screening coverage using a plausibility assessment design. The project lasted 12 months; visual Inspection with Acetic acid (VIA) screening for the women for six months and follow-up in 6 months for women receiving treatment. Results: The pre-intervention phase assessed baseline service delivery statistics in the previous 12 months drawn from the retrospective data collected as part of the routine monitoring and reporting systems. The uptake of cervical cancer screening services was low as the number of women screened in the previous 12 months was 156. Service personnel's competency level was fair (54%), and limited availability of essential equipment and supplies for cervical cancer screening services. At the post-intervention phase, the level of uptake had increased as the number of women screened was 1586 within six months in the study settings. This showed about a 100-%increase in the uptake of cervical cancer screening services compared with the baseline assessment. Also, the post-intervention level of competency of service delivery personnel had increased to 86.3%, which indicates quality improvement of the cervical cancer screening service delivery. Conclusion: the findings from the study have shown an effective approach to strengthening and improving cervical cancer screening service delivery in Southwestern Nigeria. Hence, the intervention promoted a positive attitude and health-seeking behaviour among the target population, significantly influencing the uptake of cervical cancer screening services.

Keywords: cervical cancer, screening, nigeria, health system strengthening

Procedia PDF Downloads 76

Authors: Asma Ben Hmidene, Mizuho Hanaki, Kazuma Murakami, Kazuhiro Irie, Hiroko Isoda, Hideyuki Shigemori

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Type 2 diabetes mellitus (T2DM) and Alzheimer’s disease (AD) are characterized as a peripheral metabolic disorder and a degenerative disease of the central nervous system, respectively. It is now widely recognized that T2DM and AD share many pathophysiological features including glucose metabolism, increased oxidative stress and amyloid aggregation. Amyloid beta (Aβ) is the components of the amyloid deposits in the AD brain and while the component of the amyloidogenic peptide deposit in the pancreatic islets of Langerhans is identified as human islet amyloid polypeptide (hIAPP). These two proteins are originated from the amyloid precursor protein and have a high sequence similarity. Although the amino acid sequences of amyloidogenic proteins are diverse, they all adopt a similar structure in aggregates called cross-beta-spine. Add at that, extensive studies in the past years have found that like Aβ1-42, IAPP forms early intermediate assemblies as spherical oligomers, implicating that these oligomers possess a common folding pattern or conformation. These similarities can be used in the search for effective pharmacotherapy for DM, since potent therapeutic agents such as antioxidants with a catechol moiety, proved to inhibit Aβ aggregation, may play a key role in the inhibit the aggregation of hIAPP treatment of patients with DM. Tamarix gallica is one of the halophyte species having a powerful antioxidant system. Although it was traditionally used for the treatment of various liver metabolic disorders, there is no report about the use of this plant for the treatment or prevention of T2DM and AD. Therefore, the aim of this work is to investigate their protective effect towards T2DM and AD by isolation and identification of α-glucosidase inhibitors, with antioxidant potential, that play an important role in the glucose metabolism in diabetic patient, as well as, the polymerization of hIAPP and Aβ aggregation inhibitors. Structure-activity relationship study was conducted for both assays. And as for α-glucosidase inhibitors, their mechanism of action and their synergistic potential when applied with a very low concentration of acarbose were also suggesting that they can be used not only as α-glucosidase inhibitors but also be combined with established α-glucosidase inhibitors to reduce their adverse effect. The antioxidant potential of the purified substances was evaluated by DPPH and SOD assays. Th-T assay using 42-mer amyloid β-protein (Aβ42) for AD and hIAPP which is a 37-residue peptide secreted by the pancreatic β –cells for T2DM and Transmission electronic microscopy (TEM) were conducted to evaluate the amyloid aggragation of the actives substances. For α-glucosidase, p-NPG and glucose oxidase assays were performed for determining the inhibition potential and structure-activity relationship study. The Enzyme kinetic protocol was used to study the mechanism of action. From this research, it was concluded that polyphenols playing a role in the glucose metabolism and oxidative stress can also inhibit the amyloid aggregation, and that substances with a catechol and glucuronide moieties inhibiting amyloid-β aggregation, might be used to inhibit the aggregation of hIAPP.

Keywords: α-glucosidase inhibitors, amyloid aggregation inhibition, mechanism of action, polyphenols, structure activity relationship, synergistic potential, tamarix gallica

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Authors: Maylen Villamanan Alba

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Latin America is marked by its history: conquest, colonialism, and slavery left deep footprints in most Latin American countries. Also, the past century has been affected by wars, military dictatorships, and political violence, which profoundly influenced Latin American popular culture. Consequently, reminiscences of historical crimes are frequently present in daily life, media, public opinion, and arts. This legacy is remembered in novels, paintings, songs, and films. In fact, Latin American cinema has a trend which refers to the verisimilitude with reality in fiction films. These films about historical violence are narrated as fictional characters, but their stories are based on real historical contexts. Therefore, cultural criminology has considered films as a significant field to understand social representations of violence related to historical crimes. The aim of the present contribution is to analyze the legacy of past and historical memory in social representations of violence in Latin American cinema as a critical approach to historical crimes. This qualitative research is based on content analysis. The sample is seven multi-award winning films of the International Festival of New Latin American Cinema of Havana. The films selected are Kamchatka, Argentina (2002); Carandiru, Brazil (2003); Enlightened by fire, Argentina (2005); Post-mortem, Chile (2010); No, Chile (2012) Wakolda; Argentina (2013) and The Clan, Argentina (2015). Cultural criminology highlights that cinema shapes meanings of social practices such as historical crimes. Critical criminology offers a critical theory framework to interpret Latin American cinema. This analysis reveals historical conditions deeply associated with power relationships, policy, and inequality issues. As indicated by this theory, violence is characterized as a structural process based on social asymmetries. These social asymmetries are crossed by social scopes, including institutional and personal dimensions. Thus, institutions of the states are depicted through personal stories of characters involved with human conflicts. Intimacy and social background are linked in the personages who simultaneously perform roles such as soldiers, policemen, professionals or inmates and they are at the same time depict as human beings with family, gender, racial, ideological or generational issues. Social representations of violence related to past legacy are a portrait of historical crimes perpetrated against Latin American citizens. Thereby, they have contributed to political positions, social behaviors, and public opinion. The legacy of these historical crimes suggests a path that should never be taken again. It means past legacy is a reminder, a warning, and a historic lesson for Latin American people. Social representations of violence are permeated by historical memory as denunciation under a critical approach.

Keywords: Latin American cinema, historical memory, social representation, violence

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Authors: Qaisar Ali, Waqar A. Khan, Shafiq R. Qureshi

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Heat transfer in Power Law Fluids across cylindrical surfaces has copious engineering applications. These applications comprises of areas such as underwater pollution, bio medical engineering, filtration systems, chemical, petroleum, polymer, food processing, recovery of geothermal energy, crude oil extraction, pharmaceutical and thermal energy storage. The quantum of research work with diversified conditions to study the effects of combined heat transfer and fluid flow across porous media has increased considerably over last few decades. The most non-Newtonian fluids of practical interest are highly viscous and therefore are often processed in the laminar flow regime. Several studies have been performed to investigate the effects of free and mixed convection in Newtonian fluids along vertical and horizontal cylinder embedded in a saturated porous medium, whereas very few analysis have been performed on Power law fluids along wedge. In this study, boundary layer analysis under the effects of radiation-mixed convection in power law fluids along vertical wedge in porous medium have been investigated using an implicit finite difference method (Keller box method). Steady, 2-D laminar flow has been considered under prescribed surface heat flux condition. Darcy, Boussinesq and Roseland approximations are assumed to be valid. Neglecting viscous dissipation effects and the radiate heat flux in the flow direction, the boundary layer equations governing mixed convection flow over a vertical wedge are transformed into dimensionless form. The single mathematical model represents the case for vertical wedge, cone and plate by introducing the geometry parameter. Both similar and Non- similar solutions have been obtained and results for Non similar case have been presented/ plotted. Effects of radiation parameter, variable heat flux parameter, wedge angle parameter ‘m’ and mixed convection parameter have been studied for both Newtonian and Non-Newtonian fluids. The results are also compared with the available data for the analysis of heat transfer in the prescribed range of parameters and found in good agreement. Results for the details of dimensionless local Nusselt number, temperature and velocity fields have also been presented for both Newtonian and Non-Newtonian fluids. Analysis of data revealed that as the radiation parameter or wedge angle is increased, the Nusselt number decreases whereas it increases with increase in the value of heat flux parameter at a given value of mixed convection parameter. Also, it is observed that as viscosity increases, the skin friction co-efficient increases which tends to reduce the velocity. Moreover, pseudo plastic fluids are more heat conductive than Newtonian and dilatant fluids respectively. All fluids behave identically in pure forced convection domain.

Keywords: porous medium, power law fluids, surface heat flux, vertical wedge

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Authors: Jan Masak, Eva Kvasnickova, Vladimir Scholtz, Olga Matatkova, Marketa Valkova, Alena Cejkova

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Microbial colonization of medical instruments, catheters, implants, etc. is a serious problem in the spread of nosocomial infections. Biofilms exhibit enormous resistance to environment. The resistance of biofilm populations to antibiotic or biocides often increases by two to three orders of magnitude in comparison with suspension populations. Subjects of interests are substances or physical processes that primarily cause the destruction of biofilm, while the released cells can be killed by existing antibiotics. In addition, agents that do not have a strong lethal effect do not cause such a significant selection pressure to further enhance resistance. Non-thermal plasma (NTP) is defined as neutral, ionized gas composed of particles (photons, electrons, positive and negative ions, free radicals and excited or non-excited molecules) which are in permanent interaction. In this work, the effect of NTP generated by the cometary corona with a metallic grid on the formation and stability of biofilm and metabolic activity of cells in biofilm was studied. NTP was applied on biofilm populations of Staphylococcus epidermidis DBM 3179, Pseudomonas aeruginosa DBM 3081, DBM 3777, ATCC 15442 and ATCC 10145, Escherichia coli DBM 3125 and Candida albicans DBM 2164 grown on solid media on Petri dishes and on the titanium alloy (Ti6Al4V) surface used for the production joint replacements. Erythromycin (for S. epidermidis), polymyxin B (for E. coli and P. aeruginosa), amphotericin B (for C. albicans) and ceftazidime (for P. aeruginosa) were used to study the combined effect of NTP and antibiotics. Biofilms were quantified by crystal violet assay. Metabolic activity of the cells in biofilm was measured using MTT (3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide) colorimetric test based on the reduction of MTT into formazan by the dehydrogenase system of living cells. Fluorescence microscopy was applied to visualize the biofilm on the surface of the titanium alloy; SYTO 13 was used as a fluorescence probe to stain cells in the biofilm. It has been shown that biofilm populations of all studied microorganisms are very sensitive to the type of used NTP. The inhibition zone of biofilm recorded after 60 minutes exposure to NTP exceeded 20 cm², except P. aeruginosa DBM 3777 and ATCC 10145, where it was about 9 cm². Also metabolic activity of cells in biofilm differed for individual microbial strains. High sensitivity to NTP was observed in S. epidermidis, in which the metabolic activity of biofilm decreased after 30 minutes of NTP exposure to 15% and after 60 minutes to 1%. Conversely, the metabolic activity of cells of C. albicans decreased to 53% after 30 minutes of NTP exposure. Nevertheless, this result can be considered very good. Suitable combinations of exposure time of NTP and the concentration of antibiotic achieved in most cases a remarkable synergic effect on the reduction of the metabolic activity of the cells of the biofilm. For example, in the case of P. aeruginosa DBM 3777, a combination of 30 minutes of NTP with 1 mg/l of ceftazidime resulted in a decrease metabolic activity below 4%.

Keywords: anti-biofilm activity, antibiotic, non-thermal plasma, opportunistic pathogens

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Authors: Álvaro Ramírez Vidal, Martín Muñoz Morales, Francisco Jesús Fernández Morales, Luis Rodríguez Romero, José Villaseñor Camacho, Javier Llanos López

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In recent times, environmental problems have led to the extensive use of biological systems to solve them. Among the different types of biological systems, the use of plants such as aquatic macrophytes in constructed wetlands and terrestrial plant species for treating polluted soils and sludge has gained importance. Though the use of constructed wetlands for wastewater treatment is a well-researched domain, the slowness of pollutant degradation and high biomass production pose some challenges. Plants used in CW participate in different mechanisms for the capture and degradation of pollutants that also can retain some pharmaceutical and personal care products (PPCPs) that are very persistent in the environment. Thus, these systems present advantages in line with the guidelines published for the transition towards friendly and ecological procedures as they are environmentally friendly systems, consume low energy, or capture atmospheric CO₂. However, the use of CW presents some drawbacks, as the slowness of pollutant degradation or the production of important amounts of plant biomass, which need to be harvested and managed periodically. Taking this opportunity in mind, it is important to highlight that this residual biomass (of lignocellulosic nature) could be used as the feedstock for the generation of carbonaceous materials using thermochemical transformations such as slow pyrolysis or hydrothermal carbonization to produce high-value biomass-derived carbons through sustainable processes as adsorbents, catalysts…, thereby improving the circular carbon economy. Thus, this work carried out the analysis of some PPCPs commonly found in urban wastewater, as salicylic acid or ibuprofen, to evaluate the remediation carried out for the Phragmites Australis. Then, after the harvesting, this biomass can be used to synthesize electrodes through hydrothermal carbonization (HTC) and produce high-value biomass-derived carbons with electrocatalytic activity to remove heavy metals and persistent pollutants, promoting circular economy concepts. To do this, it was chosen biomass derived from the natural environment in high environmental risk as the Daimiel Wetlands National Park in the center of Spain, and the rest of the biomass developed in a CW specifically designed to remove pollutants. The research emphasizes the impact of the composition of the biomass waste and the synthetic parameters applied during HTC on the electrocatalytic activity. Additionally, this parameter can be related to the physicochemical properties, as porosity, surface functionalization, conductivity, and mass transfer of the electrodes lytic inks. Data revealed that carbon materials synthesized have good surface properties (good conductivities and high specific surface area) that enhance the electro-oxidants generated and promote the removal of PPCPs and the chemical oxygen demand of polluted waters.

Keywords: constructed wetlands, carbon materials, heavy metals, pharmaceutical and personal care products, hydrothermal carbonization

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Authors: Pavel Bulai, Taras Pitlik, Tatsiana Kulahava, Timofei Lipski

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The method of Electrocardiography (ECG) interpretation for post-exercise recovery tracking was developed. Metabolic indices (aerobic and anaerobic) were designed using ECG-derived features. This study reports the associations between aerobic and anaerobic indices and classical parameters of the person’s physiological state, including blood biochemistry, glycogen concentration and VO2max changes. During the study 9 participants, healthy, physically active medium trained men and women, which trained 2-4 times per week for at least 9 weeks, fulfilled (i) ECG monitoring using Apple Watch Series 4 (AWS4); (ii) blood biochemical analysis; (iii) maximal oxygen consumption (VO2max) test, (iv) bioimpedance analysis (BIA). ECG signals from a single-lead wrist-wearable device were processed with detection of QRS-complex. Aerobic index (AI) was derived as the normalized slope of QR segment. Anaerobic index (ANI) was derived as the normalized slope of SJ segment. Biochemical parameters, glycogen content and VO2max were evaluated eight times within 3-60 hours after training. ECGs were recorded 5 times per day, plus before and after training, cycloergometry and BIA. The negative correlation between AI and blood markers of the muscles functional status including creatine phosphokinase (r=-0.238, p < 0.008), aspartate aminotransferase (r=-0.249, p < 0.004) and uric acid (r = -0.293, p<0.004) were observed. ANI was also correlated with creatine phosphokinase (r= -0.265, p < 0.003), aspartate aminotransferase (r = -0.292, p < 0.001), lactate dehydrogenase (LDH) (r = -0.190, p < 0.050). So, when the level of muscular enzymes increases during post-exercise fatigue, AI and ANI decrease. During recovery, the level of metabolites is restored, and metabolic indices rising is registered. It can be concluded that AI and ANI adequately reflect the physiology of the muscles during recovery. One of the markers of an athlete’s physiological state is the ratio between testosterone and cortisol (TCR). TCR provides a relative indication of anabolic-catabolic balance and is considered to be more sensitive to training stress than measuring testosterone and cortisol separately. AI shows a strong negative correlation with TCR (r=-0.437, p < 0.001) and correctly represents post-exercise physiology. In order to reveal the relation between the ECG-derived metabolic indices and the state of the cardiorespiratory system, direct measurements of VO2max were carried out at various time points after training sessions. The negative correlation between AI and VO2max (r = -0.342, p < 0.001) was obtained. These data testifying VO2max rising during fatigue are controversial. However, some studies have revealed increased stroke volume after training, that agrees with findings. It is important to note that post-exercise increase in VO2max does not mean an athlete’s readiness for the next training session, because the recovery of the cardiovascular system occurs over a substantially longer period. Negative correlations registered for ANI with glycogen (r = -0.303, p < 0.001), albumin (r = -0.205, p < 0.021) and creatinine (r = -0.268, p < 0.002) reflect the dehydration status of participants after training. Correlations between designed metabolic indices and physiological parameters revealed in this study can be considered as the sufficient evidence to use these indices for assessing the state of person’s aerobic and anaerobic metabolic systems after training during fatigue, recovery and supercompensation.

Keywords: aerobic index, anaerobic index, electrocardiography, supercompensation

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Authors: Ralph Nyadu-Addo, Francis Matambalya, Utz Dornberger

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The global music industry is a multi-billion dollar sector. The potential of Africa’s music industry is widely recognised in the socio-economic development milieu. It has impacted positively on several sectors including most especially the tourism, media and information, communication technology (ICT) among others. It is becoming increasingly clear that even in Africa (as demonstrated in Nigeria) that in addition to its intrinsic value, the sector has significant economic returns. UNCTAD observed, the creative industries offer some of the best prospects for high growth in least developed countries. The statistics from Africa may be far lower than similar sectors in developed countries but it goes to give further credence to several UNCTAD publications which say the creative industry is under researched and its potential under-estimated but holds the key to its rapid development The emerging creative economy (music in particular) has become a leading component of economic growth, employment, trade, innovation, and social cohesion in many countries. In line with these developments, the Ghana government recognizes the potential that the Creative Industries have to shape and reinforce Ghana’s economic growth. Creative sectors, particularly music, tend to rely less on sophisticated infrastructure or capital-intensive investment. Potential is particularly abundant in Africa, where musical creativity is rich, diverse, well-loved, and constantly evolving while drawing on strong traditions. The development of a popular music industry thus represents low-hanging fruit for most African economies says the World Bank. As we shift towards economic diversification using the creative industry, value is increasingly created at the intersection of arts, business and technology. Cultural and creative entrepreneurs are leading this trend. It is one of the areas where value is captured within the country as emerging trends have shown in Nigeria and Ghana among others. Yet, evidence shows that the potential of the cultural and creative sectors remains largely untapped. Furthermore, its socio-economic impact remains under-researched in many developing countries and its dynamics unknown. Despite its huge influence on music repertoire across the globe, most countries in Africa have not historically been significant markets for the international music industry. Today, that is beginning to change. Generally, reliable and adequate literature about music in the sub-region is difficult to obtain. The growing interests in academia and business cycles about a reliable data on the growing music industry in developing countries have called for an urgent need to undertake this research. Research questions: i. Who are the major stakeholders in the music value chain in Ghana? ii. How much of value is captured domestically iii. What is the economic impact of the Ghanaian music industry iv. How has the advent of ICT (internet) impacted on the music landscape? Research sources will be mainly through interviews of major stakeholders, baseline study of the industry by KPMG and content analysis of related newspapers and magazines.

Keywords: economic impact, information communications technology (ICT), music-industry, value chain

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Authors: Naresh Kumar, Savita Kumari, Naresh Kochhar

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The objective of the study was to assess the role of mineralogy and subsurface structure on water quality of Tosham, Malani Igneous Suite (MIS), Western Rajasthan, India. MIS is the largest (55,000 km2) A-type, anorogenic and high heat producing acid magmatism in the peninsular India and owes its origin to hot spot tectonics. Apart from agricultural and industrial wastes, geogenic activities cause fluctuations in quality parameters of water resources. Twenty water samples (20) selected from Tosham and surrounding areas were analyzed for As, Pb, B, Al, Zn, Fe, Ni using Inductive coupled plasma emission and F by Ion Chromatography. The concentration of As, Pb, B, Ni and F was above the stipulated level specified by BIS (Bureau of Indian Standards IS-10500, 2012). The concentration of As and Pb in surrounding areas of Tosham ranged from 1.2 to 4.1 mg/l and from 0.59 to 0.9 mg/l respectively which is higher than limits of 0.05mg/l (As) and 0.01 mg/l (Pb). Excess trace metal accumulation in water is toxic to humans and adversely affects the central nervous system, kidneys, gastrointestinal tract, skin and cause mental confusion. Groundwater quality is defined by nature of rock formation, mineral water reaction, physiography, soils, environment, recharge and discharge conditions of the area. Fluoride content in groundwater is due to the solubility of fluoride-bearing minerals like fluorite, cryolite, topaz, and mica, etc. Tosham is comprised of quartz mica schist, quartzite, schorl, tuff, quartz porphyry and associated granites, thus, fluoride is leached out and dissolved in groundwater. In the study area, Ni concentration ranged from 0.07 to 0.5 mg/l (permissible limit 0.02 mg/l). The primary source of nickel in drinking water is leached out nickel from ore-bearing rocks. Higher concentration of As is found in some igneous rocks specifically containing minerals as arsenopyrite (AsFeS), realgar (AsS) and orpiment (As2S3). MIS consists of granite (hypersolvus and subsolvus), rhyolite, dacite, trachyte, andesite, pyroclasts, basalt, gabbro and dolerite which increased the trace elements concentration in groundwater. Nakora, a part of MIS rocks has high concentration of trace and rare earth elements (Ni, Rb, Pb, Sr, Y, Zr, Th, U, La, Ce, Nd, Eu and Yb) which percolates the Ni and Pb to groundwater by weathering, contacts and joints/fractures in rocks. Additionally, geological setting of MIS also causes dissolution of trace elements in water resources beneath the surface. NE–SW tectonic lineament, radial pattern of dykes and volcanic vent at Nakora created a way for leaching of these elements to groundwater. Rain water quality might be altered by major minerals constituents of host Tosham rocks during its percolation through the rock fracture, joints before becoming the integral part of groundwater aquifer. The weathering process like hydration, hydrolysis and solution might be the cause of change in water chemistry of particular area. These studies suggest that geological relation of soil-water horizon with MIS rocks via mineralogical variations, structures and tectonic setting affects the water quality of the studied area.

Keywords: geochemistry, groundwater, malani igneous suite, tosham

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Authors: Nirmani Wijenayake, Louise Lutze-Mann, Lucy Jo, John Wilson, Vivian Yeung, Dean Lovett, Kim Snepvangers

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Sessional academic staff at universities have the most influence and impact on student learning, engagement, and experience as they have the most direct contact with undergraduate students. A blended technology-enhanced program was created for the development and support of sessional staff to ensure adequate training is provided to deliver quality educational outcomes for the students. This program combines innovative mixed media educational modules, a peer-driven support forum, and face-to-face workshops to provide a comprehensive training and support package for staff. Additionally, the program encourages the development of learning communities and peer mentoring among the sessional staff to enhance their support system. In 2018, the program was piloted on 100 sessional staff in the School of Biotechnology and Biomolecular Sciences to evaluate the effectiveness of this model. As part of the program, rotoscope animations were developed to showcase ‘typical’ interactions between staff and students. These were designed around communication, confidence building, consistency in grading, feedback, diversity awareness, and mental health and wellbeing. When surveyed, 86% of sessional staff found these animations to be helpful in their teaching. An online platform (Moodle) was set up to disseminate educational resources and teaching tips, to host a discussion forum for peer-to-peer communication and to increase critical thinking and problem-solving skills through scenario-based lessons. The learning analytics from these lessons were essential in identifying difficulties faced by sessional staff to further develop supporting workshops to improve outcomes related to teaching. The face-to-face professional development workshops were run by expert guest speakers on topics such as cultural diversity, stress and anxiety, LGBTIQ and student engagement. All the attendees of the workshops found them to be useful and 88% said they felt these workshops increase interaction with their peers and built a sense of community. The final component of the program was to use an adaptive e-learning platform to gather feedback from the students on sessional staff teaching twice during the semester. The initial feedback provides sessional staff with enough time to reflect on their teaching and adjust their performance if necessary, to improve the student experience. The feedback from students and the sessional staff on this model has been extremely positive. The training equips the sessional staff with knowledge and insights which can provide students with an exceptional learning environment. This program is designed in a flexible and scalable manner so that other faculties or institutions could adapt components for their own training. It is anticipated that the training and support would help to build the next generation of educators who will directly impact the educational experience of students.

Keywords: designing effective instruction, enhancing student learning, implementing effective strategies, professional development

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Authors: Ines Raies, Eric Kohler, Marc Fleury, Béatrice Ledésert

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In this work, the impact of clay minerals on the formation damage of sandstone reservoirs is studied to provide a better understanding of the problem of deep geothermal reservoir permeability reduction due to fine particle dispersion and migration. In some situations, despite the presence of filters in the geothermal loop at the surface, particles smaller than the filter size (<1 µm) may surprisingly generate significant permeability reduction affecting in the long term the overall performance of the geothermal system. Our study is carried out on cores from a Triassic reservoir in the Paris Basin (Feigneux, 60 km Northeast of Paris). Our goal is to first identify the clays responsible for clogging, a mineralogical characterization of these natural samples was carried out by coupling X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray Spectroscopy (EDS). The results show that the studied stratigraphic interval contains mostly illite and chlorite particles. Moreover, the spatial arrangement of the clays in the rocks as well as the morphology and size of the particles, suggest that illite is more easily mobilized than chlorite by the flow in the pore network. Thus, based on these results, illite particles were prepared and used in core flooding in order to better understand the factors leading to the aggregation and deposition of this type of clay particles in geothermal reservoirs under various physicochemical and hydrodynamic conditions. First, the stability of illite suspensions under geothermal conditions has been investigated using different characterization techniques, including Dynamic Light Scattering (DLS) and Scanning Transmission Electron Microscopy (STEM). Various parameters such as the hydrodynamic radius (around 100 nm), the morphology and surface area of aggregates were measured. Then, core-flooding experiments were carried out using sand columns to mimic the permeability decline due to the injection of illite-containing fluids in sandstone reservoirs. In particular, the effects of ionic strength, temperature, particle concentration and flow rate of the injected fluid were investigated. When the ionic strength increases, a permeability decline of more than a factor of 2 could be observed for pore velocities representative of in-situ conditions. Further details of the retention of particles in the columns were obtained from Magnetic Resonance Imaging and X-ray Tomography techniques, showing that the particle deposition is nonuniform along the column. It is clearly shown that very fine particles as small as 100 nm can generate significant permeability reduction under specific conditions in high permeability porous media representative of the Triassic reservoirs of the Paris basin. These retention mechanisms are explained in the general framework of the DLVO theory

Keywords: geothermal energy, reinjection, clays, colloids, retention, porosity, permeability decline, clogging, characterization, XRD, SEM-EDS, STEM, DLS, NMR, core flooding experiments

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Authors: Serap Durkut, A. Eser Elcin, Y. Murat Elcin

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Stimuli-sensitive polymeric hydrogels have received extensive attention in the biomedical field due to their sensitivity to physical and chemical stimuli (temperature, pH, ionic strength, light, etc.). This study describes the rheological properties of a novel thermoresponsive poly(N-vinylcaprolactam)-g-collagen hydrogel. In the study, we first synthesized a facile and novel synthetic carboxyl group-terminated thermo-responsive poly(N-vinylcaprolactam)-COOH (PNVCL-COOH) via free radical polymerization. Further, this compound was effectively grafted with native collagen, by utilizing the covalent bond between the carboxylic acid groups at the end of the chains and amine groups of the collagen using cross-linking agent (EDC/NHS), forming PNVCL-g-Col. Newly-formed hybrid hydrogel displayed novel properties, such as increased mechanical strength and thermoresponsive characteristics. PNVCL-g-Col showed low critical solution temperature (LCST) at 38ºC, which is very close to the body temperature. Rheological studies determine structural–mechanical properties of the materials and serve as a valuable tool for characterizing. The rheological properties of hydrogels are described in terms of two dynamic mechanical properties: the elastic modulus G′ (also known as dynamic rigidity) representing the reversible stored energy of the system, and the viscous modulus G″, representing the irreversible energy loss. In order to characterize the PNVCL-g-Col, the rheological properties were measured in terms of the function of temperature and time during phase transition. Below the LCST, favorable interactions allowed the dissolution of the polymer in water via hydrogen bonding. At temperatures above the LCST, PNVCL molecules within PNVCL-g-Col aggregated due to dehydration, causing the hydrogel structure to become dense. When the temperature reached ~36ºC, both the G′ and G″ values crossed over. This indicates that PNVCL-g-Col underwent a sol-gel transition, forming an elastic network. Following temperature plateau at 38ºC, near human body temperature the sample displayed stable elastic network characteristics. The G′ and G″ values of the PNVCL-g-Col solutions sharply increased at 6-9 minute interval, due to rapid transformation into gel-like state and formation of elastic networks. Copolymerization with collagen leads to an increase in G′, as collagen structure contains a flexible polymer chain, which bestows its elastic properties. Elasticity of the proposed structure correlates with the number of intermolecular cross-links in the hydrogel network, increasing viscosity. However, at 8 minutes, G′ and G″ values sharply decreased for pure collagen solutions due to the decomposition of the elastic and viscose network. Complex viscosity is related to the mechanical performance and resistance opposing deformation of the hydrogel. Complex viscosity of PNVCL-g-Col hydrogel was drastically changed with temperature and the mechanical performance of PNVCL-g-Col hydrogel network increased, exhibiting lesser deformation. Rheological assessment of the novel thermo-responsive PNVCL-g-Col hydrogel, exhibited that the network has stronger mechanical properties due to both permanent stable covalent bonds and physical interactions, such as hydrogen- and hydrophobic bonds depending on temperature.

Keywords: poly(N-vinylcaprolactam)-g-collagen, thermoresponsive polymer, rheology, elastic modulus, stimuli-sensitive

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Authors: N. Naz, A. D. Domenico, M. N. Huda

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Soft Robotics is a rapidly growing multidisciplinary field where robots are fabricated using highly deformable materials motivated by bioinspired designs. The high dexterity and adaptability to the external environments during contact make soft robots ideal for applications such as gripping delicate objects, locomotion, and biomedical devices. The actuation system of soft robots mainly includes fluidic, tendon-driven, and smart material actuation. Among them, Soft Pneumatic Actuator, also known as SPA, remains the most popular choice due to its flexibility, safety, easy implementation, and cost-effectiveness. However, at present, most of the fabrication of SPA is still based on traditional molding and casting techniques where the mold is 3d printed into which silicone rubber is cast and consolidated. This conventional method is time-consuming and involves intensive manual labour with the limitation of repeatability and accuracy in design. Recent advancements in direct 3d printing of different soft materials can significantly reduce the repetitive manual task with an ability to fabricate complex geometries and multicomponent designs in a single manufacturing step. The aim of this research work is to design and analyse the Soft Pneumatic Actuator (SPA) utilizing both conventional casting and modern direct 3d printing technologies. The mold of the SPA for traditional casting is 3d printed using fused deposition modeling (FDM) with the polylactic acid (PLA) thermoplastic wire. Hyperelastic soft materials such as Ecoflex-0030/0050 are cast into the mold and consolidated using a lab oven. The bending behaviour is observed experimentally with different pressures of air compressor to ensure uniform bending without any failure. For direct 3D-printing of SPA fused deposition modeling (FDM) with thermoplastic polyurethane (TPU) and stereolithography (SLA) with an elastic resin are used. The actuator is modeled using the finite element method (FEM) to analyse the nonlinear bending behaviour, stress concentration and strain distribution of different hyperelastic materials after pressurization. FEM analysis is carried out using Ansys Workbench software with a Yeon-2nd order hyperelastic material model. FEM includes long-shape deformation, contact between surfaces, and gravity influences. For mesh generation, quadratic tetrahedron, hybrid, and constant pressure mesh are used. SPA is connected to a baseplate that is in connection with the air compressor. A fixed boundary is applied on the baseplate, and static pressure is applied orthogonally to all surfaces of the internal chambers and channels with a closed continuum model. The simulated results from FEM are compared with the experimental results. The experiments are performed in a laboratory set-up where the developed SPA is connected to a compressed air source with a pressure gauge. A comparison study based on performance analysis is done between FDM and SLA printed SPA with the molded counterparts. Furthermore, the molded and 3d printed SPA has been used to develop a three-finger soft pneumatic gripper and has been tested for handling delicate objects.

Keywords: finite element method, fused deposition modeling, hyperelastic, soft pneumatic actuator

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Authors: Elizaveta Startseva, Elena Notina, Irina Bykova, Valentina Ulyumdzhieva, Natallia Zhabo

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With the various existing models of intercultural communication that contain a vast number of stages for foreign language acquisition, there is a need for conscious perception of the foreign culture. Such a process is associated with the emergence of linguistic conflict with the consistent students’ desire to solve the problem of the language differences, along with cultural discrepancies. The aim of this study is to present the modern ways and methods of removing psycholinguistic conflict through skills development in professional translation and intercultural communication. The study was conducted in groups of 1-4-year students of Medical Institute and Agro-Technological Institute RUDN university. In the course of training, students got knowledge in such disciplines as basic grammar and vocabulary of the English language, phonetics, lexicology, introduction to linguistics, theory of translation, annotating and referencing media texts and texts in specialty. The students learned to present their research work, participated in the University and exit conferences with their reports and presentations. Common strategies of removing linguistic and cultural conflict can be attributed to the development of such abilities of a language personality as a commitment to communication and cooperation, the formation of cultural awareness and empathy of other cultures of the individual, realistic self-esteem, emotional stability, tolerance, etc. The process of mastering a foreign language and culture of the target language leads to a reduplication of linguistic identity, which leads to successive formation of the so-called 'secondary linguistic personality.' In our study, we tried to approach the problem comprehensively, focusing on the translation gaps for technical and non-technical language still missing such a typology which could classify all of the lacunas on the same principle. When obtaining the background knowledge, students learn to overcome the difficulties posed by the national-specific and linguistic differences of cultures in contact, i.e., to eliminate the gaps (to fill in and compensate). Compensation gaps is a means of fixing it, the initial phase of elimination, followed in some cases and some not is filling semantic voids (plenus). The concept of plenus occurs in most cases of translation gaps, for example in the transcription and transliteration of (intercultural and exoticism), the replication (reproduction of the morphemic structure of words or idioms. In all the above cases the task of the translator is to ensure an identical response of the receptors of the original and translated texts, since any statement is created with the goal of obtaining communicative effect, and hence pragmatic potential is the most important part of its contents. The practical value of our work lies in improving the methodology of teaching English for specific purposes on the basis of psycholinguistic concept of the secondary language personality.

Keywords: lacuna, language barrier, plenus, secondary language personality

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Authors: Amesh P, Suneesh A S, Venkatesan K A

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The magnetic solid-phase extraction is a relatively new method among the other solid-phase extraction techniques for the separating of metal ions from aqueous solutions, such as mine water and groundwater, contaminated wastes, etc. However, the bare magnetic particles (Fe3O4) exhibit poor selectivity due to the absence of target-specific functional groups for sequestering the metal ions. The selectivity of these magnetic particles can be remarkably improved by covalently tethering the task-specific ligands on magnetic surfaces. The magnetic particles offer a number of advantages such as quick phase separation aided by the external magnetic field. As a result, the solid adsorbent can be prepared with the particle size ranging from a few micrometers to the nanometer, which again offers the advantages such as enhanced kinetics of extraction, higher extraction capacity, etc. Conventionally, the magnetite (Fe3O4) particles were prepared by the hydrolysis and co-precipitation of ferrous and ferric salts in aqueous ammonia solution. Since the covalent linking of task-specific functionalities on Fe3O4 was difficult, and it is also susceptible to redox reaction in the presence of acid or alkali, it is necessary to modify the surface of Fe3O4 by silica coating. This silica coating is usually carried out by hydrolysis and condensation of tetraethyl orthosilicate over the surface of magnetite to yield a thin layer of silica-coated magnetite particles. Since the silica-coated magnetite particles amenable for further surface modification, it can be reacted with task-specific functional groups to obtain the functionalized magnetic particles. The surface area exhibited by such magnetic particles usually falls in the range of 50 to 150 m2.g-1, which offer advantage such as quick phase separation, as compared to the other solid-phase extraction systems. In addition, the magnetic (Fe3O4) particles covalently linked on mesoporous silica matrix (MCM-41) and task-specific ligands offer further advantages in terms of extraction kinetics, high stability, longer reusable cycles, and metal extraction capacity, due to the large surface area, ample porosity and enhanced number of functional groups per unit area on these adsorbents. In view of this, the present paper deals with the synthesis of uranium specific diethylenetriamine ligand (DETA) ligand anchored on silica-coated magnetite (Fe-DETA) as well as on magnetic mesoporous silica (MCM-Fe-DETA) and studies on the extraction of uranium from aqueous solution spiked with uranium to mimic the mine water or groundwater contaminated with uranium. The synthesized solid-phase adsorbents were characterized by FT-IR, Raman, TG-DTA, XRD, and SEM. The extraction behavior of uranium on the solid-phase was studied under several conditions like the effect of pH, initial concentration of uranium, rate of extraction and its variation with pH and initial concentration of uranium, effect of interference ions like CO32-, Na+, Fe+2, Ni+2, and Cr+3, etc. The maximum extraction capacity of 233 mg.g-1 was obtained for Fe-DETA, and a huge capacity of 1047 mg.g-1 was obtained for MCM-Fe-DETA. The mechanism of extraction, speciation of uranium, extraction studies, reusability, and the other results obtained in the present study suggests Fe-DETA and MCM-Fe-DETA are the potential candidates for the extraction of uranium from mine water, and groundwater.

Keywords: diethylenetriamine, magnetic mesoporous silica, magnetic solid-phase extraction, uranium extraction, wastewater treatment

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Authors: Z. Nurzaireena, K. Azalea, T. Azirawaty, S. Jameela, G. Muralitharan

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The aim of this study is the review of the management practices of sickle cell disease patients during pregnancy, as well as the maternal and neonatal outcome at Ampang Hospital, Selangor. The study consisted of a review of pregnant patients with sickle cell disease under follow up at the Hematology Clinic, Ampang Hospital over the last seven years to assess their management and maternal-fetal outcome. The results of the review show that Ampang Hospital is considered the public hematology centre for sickle cell disease and had successfully managed three pregnancies throughout the last seven years. Patients’ presentations, managements and maternal-fetal outcome were compared and reviewed for academic improvements. All three patients were seen very early in their pregnancy and had been given a regime of folic acid, antibiotics and thrombo-prophylactic drugs. Close monitoring of maternal and fetal well being was done by the hematologists and obstetricians. Among the patients, there were multiple admissions during the pregnancy for either a painful sickle cell bone crisis, haemolysis following an infection and anemia requiring phenotype- matched blood and exchange transfusions. Broad spectrum antibiotics coverage during and infection, hydration, pain management and venous-thrombolism prophylaxis were mandatory. The pregnancies managed to reach near term in the third trimester but all required emergency caesarean section for obstetric indications. All pregnancies resulted in live births with good fetal outcome. During post partum all were nursed closely in the high dependency units for further complications and were discharged well. Post partum follow up and contraception counseling was comprehensively given for future pregnancies. Sickle cell disease is uncommonly seen in the East, especially in the South East Asian region, yet more cases are seen in the current decade due to improved medical expertise and advance medical laboratory technologies. Pregnancy itself is a risk factor for sickle cell patients as increased thrombosis event and risk of infections can lead to multiple crisis, haemolysis, anemia and vaso-occlusive complications including eclampsia, cerebrovasular accidents and acute bone pain. Patients mostly require multiple blood product transfusions thus phenotype-matched blood is required to reduce the risk of alloimmunozation. Emphasizing the risks and complications in preconception counseling and establishing an ultimate pregnancy plan would probably reduce the risk of morbidity and mortality to the mother and unborn child. Early management for risk of infection, thromboembolic events and adequate hydration is mandatory. A holistic approach involving multidisciplinary team care between the hematologist, obstetricians, anesthetist, neonatologist and close nursing care for both mother and baby would ensure the best outcome. In conclusion, sickle cell disease by itself is a high risk medical condition and pregnancy would further amplify the risk. Thus, close monitoring with combine multidisciplinary care, counseling and educating the patients are crucial in achieving the safe outcome.

Keywords: anaemia, haemoglobinopathies, pregnancy, sickle cell disease

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Authors: Varsha Puri, Sharon Hudson, Ian Kim

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Background: Incest-related childhood sexual abuse (IRCSA) is challenging to study due to the shame and secrecy experienced by its survivors. Ramifications of IRCSA worsen when it is unidentified, and interventions are not made. IRCSA perspectives are essential for future prevention and intervention strategies. However, there is limited understanding of this population’s experiences, perspectives, and long-term struggles. To date, research for IRCSA has utilized data from treatment programs and qualitative research with cohorts of 10-20 people, much of the data is from 10-40 years prior. Methods. In June 2018, an anonymous online survey was posted to multiple social media sites (e.g., Facebook IRCSA groups) and sexual abuse resource sites. Survey responses were collected for a year. The survey collected non-identifying demographics, IRCSA experiences, and outcomes data. Results: We obtained 1310 completed surveys. Demographics of all ages, racial backgrounds, financial backgrounds, and genders were obtained; the majority identified as white (81%) and female (76%). Childhood sexual abuse (CSA) started before the age of 6 in 49% and was endured for more than one year in 84% of respondents, and 39% reported ten or more years of abuse. CSA by multiple perpetrators occurred in 58%, while 8% had ten or more perpetrators. CSA by perpetrators under 21 years old was reported by 46%. Female perpetrators were reported by 28% of respondents. Fathers were the highest reported sexual abusers at 60%, and mothers were reported at 17%. Only 16% reported that at least one of their perpetrators was prosecuted for sexual abuse of a minor. Respondents confirmed that 54% of the time, they informed an adult of the abuse; only 2% agreed that “an intervention was made by the family that protected me.” A majority reported that IRCSA has negatively impacted their intimate/sexual relationships (96%) and mental health (96%). A majority reported negative impacts on biological family relationships (88%), physical health (73%), finances (59%), educational achievement (57%), and employment (56%). When asked about suffering from addiction, 85% of respondents answered yes. Prevention strategies selected most by respondents include early school education around CSA prevention (67%), removing the statute of limitations for reporting CSA (69%), and improved laws protecting IRCSA survivors (63%). Conclusion: The data document that IRCSA can be pervasive, and the dearth of intervention and support for survivors have major lasting impacts. Survivors have a unique and valuable perspective on what interventions are needed to prevent IRCSA and support survivors; their voice has long been unheard in crafting prevention and intervention policies and services. These results thus provide an important call to action from these critical stakeholders. Pediatricians should recognize that perpetrators can be pediatric patients, women, and parents. Pediatricians can advocate for more early CSA prevention education and policy changes that remove the statute of limitations for reporting CSA.

Keywords: incest, childhood sexual abuse, incest-related childhood sexual abuse, incest survivor

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Authors: T. P. Sathishkumar, P. Navaneethakrishnan

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The research work investigates the variation of tensile properties for the sansevieria ehrenbergii fiber (SEF) and SEF reinforced polyester composites respect to various water absorption time. The experiments were conducted according to ATSM D3379-75 and ASTM D570 standards. The percentage of water absorption for composite specimens was measured according to ASTM D570 standard. The fiber of SE was cut in to 30 mm length for preparation of the composites. The simple hand lay-up method followed by compression moulding process adopted to prepare the randomly oriented SEF reinforced polyester composites at constant fiber weight fraction of 40%. The surface treatment was done on the SEFs with various chemicals such as NaOH, KMnO4, Benzoyl Peroxide, Benzoyl Chloride and Stearic Acid before preparing the composites. NaOH was used for pre-treatment of all other chemical treatments. The morphology of the tensile fractured specimens studied using the Scanning Electron Microscopic. The tensile strength of the SEF and SEF reinforced polymer composites were carried out with various water absorption time such as 4, 8, 12, 16, 20 and 24 hours respectively. The result shows that the tensile strength was drop off with increase in water absorption time for all composites. The highest tensile property of raw fiber was found due to lowest moistures content. Also the chemical bond between the cellulose and cementic materials such as lignin and wax was highest due to lowest moisture content. Tensile load was lowest and elongation was highest for the water absorbed fibers at various water absorption time ranges. During this process, the fiber cellulose inhales the water and expands the primary and secondary fibers walls. This increases the moisture content in the fibers. Ultimately this increases the hydrogen cation and the hydroxide anion from the water. In tensile testing, the water absorbed fibers shows highest elongation by stretching of expanded cellulose walls and the bonding strength between the fiber cellulose is low. The load carrying capability was stable at 20 hours of water absorption time. This could be directly affecting the interfacial bonding between the fiber/matrix and composite strength. The chemically treated fibers carry higher load and lower elongation which is due to removal of lignin, hemicellulose and wax content. The water time absorption decreases the tensile strength of the composites. The chemically SEF reinforced composites shows highest tensile strength compared to untreated SEF reinforced composites. This was due to highest bonding area between the fiber/matrix. This was proven in the morphology at the fracture zone of the composites. The intra-fiber debonding was occurred by water capsulation in the fiber cellulose. Among all, the tensile strength was found to be highest for KMnO4 treated SEF reinforced composite compared to other composites. This was due to better interfacial bonding between the fiber-matrix compared to other treated fiber composites. The percentage of water absorption of composites increased with time of water absorption. The percentage weight gain of chemically treated SEF composites at 4 hours to zero water absorption are 9, 9, 10, 10.8 and 9.5 for NaOH, BP, BC, KMnO4 and SA respectively. The percentage weight gain of chemically treated SEF composites at 24 hours to zero water absorption 5.2, 7.3, 12.5, 16.7 and 13.5 for NaOH, BP, BC, KMnO4 and SA respectively. Hence the lowest weight gain was found for KMnO4 treated SEF composites by highest percentage with lowest water uptake. However the chemically treated SEF reinforced composites is possible materials for automotive application like body panels, bumpers and interior parts, and household application like tables and racks etc.

Keywords: fibres, polymer-matrix composites (PMCs), mechanical properties, scanning electron microscopy (SEM)

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Authors: Mehraveh Taghizadeh

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Iran is home to a diverse range of ethnic groups such as Baloch, Kurds, Persians, Lors, Arabs, and Turks. The Persian ethnicity is the largest group, while Baloch people are considered a minority residing on the southeastern border of the country with different language and religion. As a consequence, Political discussions have often prioritized national identity and national security over Baloch ethnic identity. However, to improve intercultural understanding and reduce cultural schemas, it's crucial to decrease ethnocentrism and increase intercultural communication. In the meantime, Kerman, a multicultural province that borders Sistan and Baluchistan, has become a destination for Baloch immigrants. By recognizing the current status of intercultural competence, we can develop effective policies for expanding intercultural communication and creating a more inclusive and peaceful society. As a result, this research aims to study the domain of intercultural sensitivity between Persians and Baloch in Kerman. Therefore, the question is how do Persians and Baloch ethnicities perceive each other? This study represents the first exploration of communication dynamics between Persians and Baloch individuals. Utilizing a qualitative approach, this study employs thematic analysis in conjunction with Bennett's intercultural sensitivities model. The model comprises two components: ethnocentrism, which spans from denial and defense to minimization, and ethno-relativism, which ranges from acceptance and adaptation to integration. To attain this objective, 30 individuals from Persian and Baloch ethnicities were interviewed using a semi-structured format. it analysis suggests that the Baluch and Persians exhibit a range of intercultural sensitivities characterized by defensive and minimizing attitudes in the ethnocentrism domain, and accepting attitudes in the ethno-relativism domain. The concept of minimization involves recognizing the shared humanity and positive schemas of both groups. Furthermore, in the adaptation domain, Persians' efforts to assimilate into Baloch culture at an acceptance level are primarily focused on the civilizational dimension, including using traditional Balochi clothing designs on their clothes. The Persians hold intercultural schemas about the Baloch people, including notions of religious fanaticism, tribalism, poverty, smuggling, and a nomadic way of life. Conversely, the Baloch people have intercultural schemas about Persians including religious fanaticism, disdain towards the Baloch, and ethnocentrism. Both groups tend to tie ethnicity to religion and judge each other accordingly. Also, the origin of these schemas is in the representation of the media and the encounter without interaction between the two ethnic groups. These findings indicate that they have not received adaptation and integration levels in ethno-relativism. Furthermore, the results indicate that developing personal communication in multicultural environments reduces intercultural sensitivity, and increases positive interactions and civilizational dialogues. People can understand each other better and perform better in their daily lives.

Keywords: intercultural communication, intercultural sensitivity, interethnic communication, Iran, Baloch, Persians

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Authors: Chinwe Okpoko, Vivian Atasie

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One of the leading causes of death amongst women of child-bearing age in southeast Nigeria is pregnancy. Women in the reproductive age group die at a higher rate than men of the same age bracket. Furthermore, most maternal deaths occur among poor women who live in rural communities, and who generally fall within the low socio-economic group in society. Failure of policy makers and the media to create the strategic awareness and communication that conform with the sensibilities of this group account, in part, for the persistence of this malaise. Family planning (FP) is an essential component of safe motherhood, which is designed to ensure that women receive high-quality care to achieve an optimum level of health of mother and infant. The aim is to control the number of children a woman can give birth to and prevent maternal and child mortality and morbidity. This is what sustainable development goal (SDG) health target of World Health Organization (WHO) also strives to achieve. FP programmes reduce exposure to the risks of child-bearing. Indeed, most maternal deaths in the developing world can be prevented by fully investing simultaneously in FP and maternal and new-born care. Given the intrinsic value of communication in health care delivery, it is vital to adopt the most efficacious means of awareness creation and communication amongst rural women in FP. In a country where over 50% of her population resides in rural areas with attendant low-level profile standard of living, the need to communicate health information like FP through indigenous channels becomes pertinent. Interpersonal communication amongst family, friends, religious groups and other associations, is an efficacious means of communicating social issues in rural Africa. Communication in informal settings identifies with the values and social context of the recipients. This study therefore sought to determine the place of interpersonal communication on the knowledge of rural women on FP and how it influences uptake of FP. Descriptive survey design was used in the study, with interviewer administered questionnaire constituting the instrument for data collection. The questionnaire was administered on 385 women from rural communities in southeast Nigeria. The results show that majority (58.5%) of the respondents agreed that interpersonal communication helps women understand how to plan their family size. Many rural women (82%) prefer the short term natural method to the more effective modern contraceptive methods (38.1%). Husbands’ approval of FP, as indicated in the Mean response of 2.56, is a major factor that accounts for the adoption of FP messages among rural women. Socio-demographic data also reveal that educational attainment and/or exposure influenced women’s acceptance or otherwise of FP messages. The study, therefore, recommends amongst others, the targeting of husbands in subsequent FP communication interventions, since they play major role on contraceptive usage.

Keywords: family planning, interpersonal communication, interpersonal interaction, traditional communication

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Authors: Dominik Halstrup, Marlene Schriever

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The industry, as one of the main energy consumer, is of critical importance along the way of transforming the energy system to Renewable Energies. The distributed character of the Energy Transition demands for further flexibility being introduced to the grid. In order to shed further light on the acceptance of Electric Energy Storage (ESS) from an industrial point of view, this study therefore examines the German manufacturing industry. The analysis in this paper uses data composed of a survey amongst 101 manufacturing companies in Germany. Being part of a two-stage research design, both qualitative and quantitative data was collected. Based on a literature review an acceptance concept was developed in the paper and four user-types identified: (Dedicated) User, Impeded User, Forced User and (Dedicated) Non-User and incorporated in the questionnaire. Both descriptive and bivariate analysis is deployed to identify the level of acceptance in the different organizations. After a factor analysis has been conducted, variables were grouped to form independent acceptance factors. Out of the 22 organizations that do show a positive attitude towards ESS, 5 have already implemented ESS and show a positive attitude towards ESS. They can be therefore considered ‘Dedicated Users’. The remaining 17 organizations have a positive attitude but have not implemented ESS yet. The results suggest that profitability plays an important role as well as load-management systems that are already in place. Surprisingly, 2 organizations have implemented ESS even though they have a negative attitude towards it. This is an example for a ‘Forced User’ where reasons of overriding importance or supporters with overriding authority might have forced the company to implement ESS. By far the biggest subset of the sample shows (critical) distance and can therefore be considered ‘(Dedicated) Non-Users’. The results indicate that the majority of the respondents have not thought ESS in their own organization through yet. For the majority of the sample one can therefore not speak of critical distance but rather a distance due to insufficient information and the perceived unprofitability. This paper identifies the relative state of acceptance of ESS in the manufacturing industry as well as current reasons for hindrance and perspectives for future growth of ESS in an industrial setting from a policy level. The interest that is currently generated by the media could be channeled and taken into a more substantial and individual discussion about ESS in an industrial setting. If the current perception of profitability could be addressed and communicated accordingly, ESS and their use in for instance cooperative business models could become a topic for more organizations in Germany and other parts of the world. As price mechanisms tend to favor existing technologies, policy makers need to further access the use of ESS and acknowledge the positive effects when integrated in an energy system. The subfields of generation, transmission and distribution become increasingly intertwined. New technologies and business models, such as ESS or cooperative arrangements entering the market, increase the number of stakeholders. Organizations need to find their place within this array of stakeholders.

Keywords: acceptance, energy storage solutions, German energy transition, manufacturing industry

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Authors: Miroslava Cuperlovic-Culf, Lipu Wang, Ketty Boyle, Nadine Makley, Ian Burton, Anissa Belkaid, Mohamed Touaibia, Marc E. Surrette

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Metabolic changes are one of the major factors in the development of a variety of diseases in various species. Metabolism of agricultural plants is altered the following infection with pathogens sometimes contributing to resistance. At the same time, pathogens use metabolites for infection and progression. In humans, metabolism is a hallmark of cancer development for example. Quantified metabolomics data combined with other omics or clinical data and analyzed using various unsupervised and supervised methods can lead to better diagnosis and prognosis. It can also provide information about resistance as well as contribute knowledge of compounds significant for disease progression or prevention. In this work, different methods for metabolomics quantification and analysis from Nuclear Magnetic Resonance (NMR) measurements that are used for investigation of disease development in wheat and human cells will be presented. One-dimensional 1H NMR spectra are used extensively for metabolic profiling due to their high reliability, wide range of applicability, speed, trivial sample preparation and low cost. This presentation will describe a new method for metabolite quantification from NMR data that combines alignment of spectra of standards to sample spectra followed by multivariate linear regression optimization of spectra of assigned metabolites to samples’ spectra. Several different alignment methods were tested and multivariate linear regression result has been compared with other quantification methods. Quantified metabolomics data can be analyzed in the variety of ways and we will present different clustering methods used for phenotype determination, network analysis providing knowledge about the relationships between metabolites through metabolic network as well as biomarker selection providing novel markers. These analysis methods have been utilized for the investigation of fusarium head blight resistance in wheat cultivars as well as analysis of the effect of estrogen receptor and carbonic anhydrase activation and inhibition on breast cancer cell metabolism. Metabolic changes in spikelet’s of wheat cultivars FL62R1, Stettler, MuchMore and Sumai3 following fusarium graminearum infection were explored. Extensive 1D 1H and 2D NMR measurements provided information for detailed metabolite assignment and quantification leading to possible metabolic markers discriminating resistance level in wheat subtypes. Quantification data is compared to results obtained using other published methods. Fusarium infection induced metabolic changes in different wheat varieties are discussed in the context of metabolic network and resistance. Quantitative metabolomics has been used for the investigation of the effect of targeted enzyme inhibition in cancer. In this work, the effect of 17 β -estradiol and ferulic acid on metabolism of ER+ breast cancer cells has been compared to their effect on ER- control cells. The effect of the inhibitors of carbonic anhydrase on the observed metabolic changes resulting from ER activation has also been determined. Metabolic profiles were studied using 1D and 2D metabolomic NMR experiments, combined with the identification and quantification of metabolites, and the annotation of the results is provided in the context of biochemical pathways.

Keywords: metabolic biomarkers, metabolic network, metabolomics, multivariate linear regression, NMR quantification, quantified metabolomics, spectral alignment

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Authors: K. K. Balavenkatraman, B. Bertschi, K. Bigot, A. Grevot, A. Doelemeyer, S. D. Chibout, A. Wolf, F. Pognan, N. Manevski, O. Kretz, P. Swart, K. Litherland, J. Ashton-Chess, B. Ling, R. Wettstein, D. J. Schaefer

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Skin toxicity is poorly detected during preclinical studies, and drug-induced side effects in humans such as rashes, hyperplasia or more serious events like bullous pemphigus or toxic epidermal necrolysis represent an important hurdle for clinical development. In vitro keratinocyte-based epidermal skin models are suitable for the detection of chemical-induced irritancy, but do not recapitulate the biological complexity of full skin and fail to detect potential serious side-effects. Normal healthy skin explants may represent a valuable complementary tool, having the advantage of retaining the full skin architecture and the resident immune cell diversity. This study investigated several conditions for the maintenance of good morphological structure after several days of culture and the retention of phase II metabolism for 24 hours in skin explants in vitro. Human skin samples were collected with informed consent from patients undergoing plastic surgery and immediately transferred and processed in our laboratory by removing the underlying dermal fat. Punch biopsies of 4 mm diameter were cultured in an air-liquid interface using transwell filters. Different cultural conditions such as the effect of calcium, temperature and cultivation media were tested for a period of 14 days and explants were histologically examined after Hematoxylin and Eosin staining. Our results demonstrated that the use of Williams E Medium at 32°C maintained the physiological integrity of the skin for approximately one week. Upon prolonged incubation, the upper layers of the epidermis become thickened and some dead cells are present. Interestingly, these effects were prevented by addition of EGFR inhibitors such as Afatinib or Erlotinib. Phase II metabolism of the skin such as glucuronidation (4-methyl umbeliferone), sulfation (minoxidil), N-acetyltransferase (p-toluidene), catechol methylation (2,3-dehydroxy naphthalene), and glutathione conjugation (chlorodinitro benzene) were analyzed by using LCMS. Our results demonstrated that the human skin explants possess metabolic activity for a period of at least 24 hours for all the substrates tested. A time course for glucuronidation with 4-methyl umbeliferone was performed and a linear correlation was obtained over a period of 24 hours. Longer-term culture studies will indicate the possible evolution of such metabolic activities. In summary, these results demonstrate that human skin explants maintain a normal structure for several days in vitro and are metabolically active for at least the first 24 hours. Hence, with further characterisation, this model may be suitable for the study of drug-induced toxicity.

Keywords: human skin explant, phase II metabolism, epidermal growth factor receptor, toxicity

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