Search results for: interest rate risk

Authors: Ulugbek Azimov, Nearchos Stylianidis, Nobuyuki Kawahara, Eiji Tomita

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A chemical kinetics and computational fluid-dynamics (CFD) analysis was performed to evaluate the combustion of syngas derived from biomass and coke-oven solid feedstock in a micro-pilot ignited supercharged dual-fuel engine under lean conditions. For this analysis, a new reduced syngas chemical kinetics mechanism was constructed and validated by comparing the ignition delay and laminar flame speed data with those obtained from experiments and other detail chemical kinetics mechanisms available in the literature. The reaction sensitivity analysis was conducted for ignition delay at elevated pressures in order to identify important chemical reactions that govern the combustion process. The chemical kinetics of NOx formation was analyzed for H2/CO/CO2/CH4 syngas mixtures by using counter flow burner and premixed laminar flame speed reactor models. The new mechanism showed a very good agreement with experimental measurements and accurately reproduced the effect of pressure, temperature and equivalence ratio on NOx formation. In order to identify the species important for NOx formation, a sensitivity analysis was conducted for pressures 4 bar, 10 bar and 16 bar and preheat temperature 300 K. The results show that the NOx formation is driven mostly by hydrogen based species while other species, such as N2, CO2 and CH4, have also important effects on combustion. Finally, the new mechanism was used in a multidimensional CFD simulation to predict the combustion of syngas in a micro-pilot-ignited supercharged dual-fuel engine and results were compared with experiments. The mechanism showed the closest prediction of the in-cylinder pressure and the rate of heat release (ROHR).

Keywords: syngas, chemical kinetics mechanism, internal combustion engine, NOx formation

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Authors: Muhammad Farooq, Muhammad Idrees

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The present study has been designed to explore the causes and effects of Youth Bulge in Pakistan. However, youth bulge is a part of population segment which create problem for the whole society. The youth bulge is a common phenomenon in many developing countries, and in particular, in the least developed countries. It is often due to a stage of development where a country achieves success in reducing infant mortality but mothers still have a high fertility rate. The result is that a large share of the population is comprised of children and young adults, and today’s children are tomorrow’s young adults. Youth often play a prominent role in political violence and the existence of a “youth bulge” has been associated with times of political crisis. The population pyramid of Pakistan represents a large youth proportion and our government did not use that youth in positive way and did not provide them opportunity for development, this situation creates frustration in youth that leads them towards conflict, unrest and violence. This study will be focus on the opportunity and motives of the youth bulge situation in Pakistan in the lens of youth bulge theory. Moreover, it will give some suggestions to utilize youth in the development activities and avoid youth bulge situation in Pakistan. The present research was conducted in the metropolitan entities of Punjab, Pakistan. A sample of 300 respondents was taken from three randomly selected metropolitan entities (Faisalabad, Lahore and Rawalpindi) of Punjab Province of Pakistan. Information regarding demography, household, locality and other socio-cultural variables related to causes and effects of youth bulge in the state was collected through a well structured interview schedule. Mean, Standard Deviation and frequency distribution were used to check the measure of central tendency. Multiple linear regression was also applied to measure the influence of various independent variables on the response variable.

Keywords: youth bulge, violence, conflict, social unrest, crime, metropolitan entities, mean, standard deviation, multiple linear regression

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Authors: Paola Villoria Sáez, Mercedes Del Río Merino, Jaime Santa Cruz Astorqui, Antonio Rodríguez Sánchez

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The Spanish construction industry generates large volumes of waste. However, despite the legislative improvements introduced for construction and demolition waste (CDW), construction waste recycling rate remains well below other European countries and also below the target set for 2020. This situation can be due to many difficulties. i.e.: The difficulty of onsite segregation or the estimation in advance of the total amount generated. Despite these difficulties, the proper management of CDW must be one of the main aspects to be considered by the construction companies. In this sense, some large national companies are implementing Integrated Management Systems (IMS) including not only quality and safety aspects, but also environment issues. However, although this fact is a reality for large construction companies still the vast majority of companies need to adopt this trend. In short, it is common to find in small and medium enterprises a decentralized management system: A single system of quality management, another for system safety management and a third one for environmental management system (EMS). In addition, the EMSs currently used address CDW superficially and are mainly focus on other environmental concerns such as carbon emissions. Therefore, this research determines and implements a specific best practice management system for CDW based on eight procedures in a Spanish Construction company. The main advantages and drawbacks of its implementation are highlighted. Results of this study show that establishing and implementing a CDW management system in building works, improve CDW quantification as the company obtains their own CDW generation ratio. This helps construction stakeholders when developing CDW Management Plans and also helps to achieve a higher adjustment of CDW management costs. Finally, integrating this CDW system with the EMS of the company favors the cohesion of the construction process organization at all stages, establishing responsibilities in the field of waste and providing a greater control over the process.

Keywords: construction and demolition waste, waste management, best practices, waste minimization, building, quality management systems

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Authors: Cornelius Femi Popoola

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Nigerian manufacturing industry, particularly the flour producing firms play vital roles in Nigerian economy. This sector’s quality management practice is given a little attention along with organizational factors that hinder successful practice of total quality management which needs to be documented. Honeywell Flour Mills Plc operate in Nigeria with an appreciable number of products that serves this sector of the economy. Internal-external disposition of the company and total quality practice of the company deserve some elucidations. Hence, this study examined the influence of organizational factors on total quality management practice of Nigerian manufacturing industry, using Honeywell Flour Mills Plc as a case study. The study employed the correlational type of descriptive survey research design. The population consisted of 656 staff of Honeywell Flour Mills Plc, out of which 235 members were selected through scientific sampling method developed by Paler-Calmorin and Calmorin. A total of 235 copies of questionnaires titled 'Organisational Factors and Total Quality Management Practices (QF-TQM) Questionnaire' were administered with a response rate of 66 copies returned. The following variables were applied internal organisational factors (IOFs), external organizational factors (EOFs) and total quality management (TQM). Data generated were analysed using frequency distribution and regression analysis at 0.05 level. The findings revealed that IOFs positively and significantly related with TQM (r = .147**, N= 64, P(.000) < .01). Also, EOFs negatively and significantly related with TQM (r = -.117, N= 64, P(.000) < .01). Findings showed that internal and external organizational factors jointly influenced TQM practiced in F₍₂,₆₁₎=22.250; R²=.629; Adj.R²=.603; P(.000) < .05). The study concluded that organizational factors are determinants of TQM practice in Nigerian manufacturing industry. It is recommended that both internal and external organizational factors influencing TQM practices should be considered in the development of TQM strategies.

Keywords: external organizational factors, internal organisational factors, Nigerian manufacturing industry, total quality management

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Authors: Haroon Khan, Chul Min Kim, Sung Yeol Kim, Sanket Goel, Prabhat K. Dwivedi, Ashutosh Sharma, Gyu Man Kim

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Enzymatic biofuel cells (EBFCs) have drawn the attention of researchers due to its demanding application in medical implants. In EBFCs, electricity is produced with the help of redox enzymes. In this study, we report the fabrication of membraneless EBFC with new design of electrodes to overcome microchannel related limitations. The device consists of double layer of electrodes on both sides of Y-shaped microchannel to reduce the effect of oxygen depletion layer and diffusion of fuel and oxidant at the end of microchannel. Moreover, the length of microchannel was reduced by half keeping the same area of multiwalled carbon nanotubes (MWCNT) electrodes. Polydimethylsiloxane (PDMS) stencils were used to pattern MWCNT electrodes on etched Indium Tin Oxide (ITO) glass. PDMS casting was used to fabricate microchannel of the device. Both anode and cathode were modified with glucose oxidase and laccase. Furthermore, these enzymes were covalently bound to carboxyl MWCNTs with the help of EDC/NHS. Glucose used as fuel was oxidized by glucose oxidase at anode while oxygen was reduced to water at the cathode side. The resulted devices were investigated with the help of polarization curves obtained from Chronopotentiometry technique by using potentiostat. From results, we conclude that the performance of double layer EBFC is improved 15 % as compared to single layer EBFC delivering maximum power density of 71.25 µW cm-2 at a cell potential of 0.3 V and current density of 250 µA cm-2 at micro channel height of 450-µm and flow rate of 25 ml hr-1. However, the new device was stable only for three days after which its power output was rapidly dropped by 75 %. This work demonstrates that the power output of membraneless EBFC is improved comparatively, but still efforts will be needed to make the device stable over long period of time.

Keywords: EBFC, glucose, MWCNT, microfluidic

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Authors: Caroline Rocco, Feyza Karasu, Céline Croutxé-Barghorn, Xavier Allonas, Maxime Lecompère, Gérard Riess, Yujing Zhang, Catarina Esteves, Leendert van der Ven, Rolf van Benthem Gijsbertus de With

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Acrylates are widely used in UV-curing technology. Their high reactivity can, however, limit their conversion due to early vitrification. In addition, the free radical photopolymerization is known to be sensitive to oxygen inhibition leading to tacky surfaces. Although epoxides can lead to full polymerization, they are sensitive to humidity and exhibit low polymerization rate. To overcome the intrinsic limitations of both classes of monomers, Interpenetrating Polymer Networks (IPNs) can be synthesized. They consist of at least two cross linked polymers which are permanently entangled. They can be achieved under thermal and/or light induced polymerization in one or two steps approach. IPNs can display homogeneous to heterogeneous morphologies with various degrees of phase separation strongly linked to the monomer miscibility and also synthesis parameters. In this presentation, we synthesize UV-cured methacrylate - epoxide based IPNs with different chemical compositions in order to get a better understanding of their formation and phase separation. Miscibility before and during the photopolymerization, reaction kinetics, as well as mechanical properties and morphology have been investigated. The key parameters controlling the morphology and the phase separation, namely monomer miscibility and synthesis parameters have been identified. By monitoring the stiffness changes on the film surface, atomic force acoustic microscopy (AFAM) gave, in conjunction with polymerization kinetic profiles and thermomechanical properties, explanations and corroborated the miscibility predictions. When varying the methacrylate / epoxide ratio, it was possible to move from a miscible and highly-interpenetrated IPN to a totally immiscible and phase-separated one.

Keywords: investigation of properties and morphology, kinetics, phase separation, UV-cured IPNs

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Authors: Young-Taeg Kim, Gwang Ho Seo, Hyungju Oh, Ho Kyung Ha, Kuk Jin Kim

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Kim et al., hypothesized an increase in volume transport in the Korea Strait based on the concurrent increase in water temperature and mean sea level observed by the Korea Hydrographic and Oceanographic Agency (KHOA) in the vicinity of the Korea Strait from 2000 to 2009. Since then, to our best knowledge, no definitive studies have been reported on the increase in volume transport through the Korea Strait, but the observed water temperature (2000-2021) and sea level (1989-2021) in the Korea Strait and East Sea have been found to be increasing. In particular, the rapid increase rate in the mean sea level rise (2.55~3.53 mm/y) in these areas cannot be explained by only steric effect due to the increased water temperature. It is more reasonable interpretation that the sea level rise is due to an increase in the volume transport of warm and salty currents. If the increase in the volume transport is explained by the geostrophic equation without considering the sea level rise in the Korea Strait, the current velocity should increase. However, up to now, there are no reports of an increase in current velocity from direct observations using ADCP (e.g., observations of Camellia) or from various numerical models. Therefore, the increase in volume transport cannot be explained by the geostrophic equation. Another possible explanation for the increase in the volume transport is the effect of wind. Although Korea is dominated by monsoon, it is affected by winds according to El Niño and La Niña, which have a cycle of about 3 to 4 years. During El Niño (La Niña), northerly winds (southerly winds) prevail in Korea. Consequently, it is inferred that the transported volume in the Korea Strait slowly increases interannually. However, in this study, it was difficult to find a clear correlation between annually-averaged mean sea level and El Niño (or La Niña) during 1989-2021. This is probably due to the interactions of the PDO (Pacific Decadal Oscillation) and AO (Arctic Oscillation) along with the ENSO (El niño-Southern Oscillation). However, it is clear that the interannual variability of winds is affecting the volume transport in the Korean Strait. On the other hand, the effect of global sea level rise on the volume transport in the Korea Strait is small compared to the interannual variability of the volume transport, but it seems to play a constant role.

Keywords: mean sea level, volume transport, El nino, La nina

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Authors: Milton Ixquiac, Erick Montenegro, Francisco Reynoso, Matthew Schmidt, Thomas Mazur, Tianyu Zhao, Hiram Gay, Geoffrey Hugo, Lauren Henke, Jeff Michael Michalski, Angel Velarde, Vicky de Falla, Franky Reyes, Osmar Hernandez, Edgar Aparicio Ruiz, Baozhou Sun

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Purpose: Radiotherapy departments in low- and middle-income countries (LMICs) like Guatemala have recently introduced intensity-modulated radiotherapy (IMRT). IMRT has become the standard of care in high-income countries (HIC) due to reduced toxicity and improved outcomes in some cancers. The purpose of this work is to show the agreement between the dosimetric results shown in the Dose Volume Histograms (DVH) to the objectives proposed in the adopted protocol. This is the initial experience with an O-ring Linac. Methods and Materials: An O-Linac Linac was installed at our clinic in Guatemala in 2019 and has been used to treat approximately 90 patients daily with IMRT. This Linac is a completely Image Guided Device since to deliver each radiotherapy session must take a Mega Voltage Cone Beam Computerized Tomography (MVCBCT). In each MVCBCT, the Linac deliver 9 UM, and they are taken into account while performing the planning. To start the standardization, the TG263 was employed in the nomenclature and adopted a hypofractionated protocol to treat ChestWall, including supraclavicular nodes achieving 40.05Gy in 15 fractions. The planning was developed using 4 semiarcs from 179-305 degrees. The planner must create optimization volumes for targets and Organs at Risk (OARs); the difficulty for the planner was the dose base due to the MVCBCT. To evaluate the planning modality, we used 30 chestwall cases. Results: The plans created manually achieve the protocol objectives. The protocol objectives are the same as the RTOG1005, and the DHV curves look clinically acceptable. Conclusions: Despite the O-ring Linac doesn´t have the capacity to obtain kv images, the cone beam CT was created using MV energy, the dose delivered by the daily image setup process still without affect the dosimetric quality of the plans, and the dose distribution is acceptable achieving the protocol objectives.

Keywords: hypofrationation, VMAT, chestwall, radiotherapy planning

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Authors: Michael Moeti, Khuliso Sigama, Thapelo Samuel Matlala

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One of the principal challenges that the world is confronted with is insecurity. The crime rate is increasing exponentially, and protecting our physical assets especially in the motorist industry, is becoming impossible when applying our own strength. The need to develop technological solutions that detect and report theft without any human interference is inevitable. This is critical, especially for vehicle owners, to ensure theft detection and speedy identification towards recovery efforts in cases where a vehicle is missing or attempted theft is taking place. The vehicle theft detection system uses Convolutional Neural Network (CNN) to recognize the driver's face captured using an installed mobile phone device. The location identification function uses a Global Positioning System (GPS) to determine the real-time location of the vehicle. Upon identification of the location, Global System for Mobile Communications (GSM) technology is used to report or notify the vehicle owner about the whereabouts of the vehicle. The installed mobile app was implemented by making use of python as it is undoubtedly the best choice in machine learning. It allows easy access to machine learning algorithms through its widely developed library ecosystem. The graphical user interface was developed by making use of JAVA as it is better suited for mobile development. Google's online database (Firebase) was used as a means of storage for the application. The system integration test was performed using a simple percentage analysis. Sixty (60) vehicle owners participated in this study as a sample, and questionnaires were used in order to establish the acceptability of the system developed. The result indicates the efficiency of the proposed system, and consequently, the paper proposes the use of the system can effectively monitor the vehicle at any given place, even if it is driven outside its normal jurisdiction. More so, the system can be used as a database to detect, locate and report missing vehicles to different security agencies.

Keywords: CNN, location identification, tracking, GPS, GSM

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Authors: Ben Otange, Wolfgang Parak, Florian Schulz, Michael Alexander Rubhausen

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The feasibility of extending the usage of molecular imprinting technique in complex biomolecules is demonstrated in this research. This technique is promising in diverse applications in areas such as drug delivery, diagnosis of diseases, catalysts, and impurities detection as well as treatment of various complications. While molecularly imprinted polymers MIP remain robust in the synthesis of molecules with remarkable binding sites that have high affinities to specific molecules of interest, extending the usage to complex biomolecules remains futile. This work reports on the successful synthesis of MIP from complex proteins: BSA, Transferrin, and MUC1. We show in this research that despite the heterogeneous binding sites and higher conformational flexibility of the chosen proteins, relying on their respective epitopes and motifs rather than the whole template produces highly sensitive and selective MIPs for specific molecular binding. Introduction: Proteins are vital in most biological processes, ranging from cell structure and structural integrity to complex functions such as transport and immunity in biological systems. Unlike other imprinting templates, proteins have heterogeneous binding sites in their complex long-chain structure, which makes their imprinting to be marred by challenges. In addressing this challenge, our attention is inclined toward the targeted delivery, which will use molecular imprinting on the particle surface so that these particles may recognize overexpressed proteins on the target cells. Our goal is thus to make surfaces of nanoparticles that specifically bind to the target cells. Results and Discussions: Using epitopes of BSA and MUC1 proteins and motifs with conserved receptors of transferrin as the respective templates for MIPs, significant improvement in the MIP sensitivity to the binding of complex protein templates was noted. Through the Fluorescence Correlation Spectroscopy FCS measurements on the size of protein corona after incubation of the synthesized nanoparticles with proteins, we noted a high affinity of MIPs to the binding of their respective complex proteins. In addition, quantitative analysis of hard corona using SDS-PAGE showed that only a specific protein was strongly bound on the respective MIPs when incubated with similar concentrations of the protein mixture. Conclusion: Our findings have shown that the merits of MIPs can be extended to complex molecules of higher biomolecular mass. As such, the unique merits of the technique, including high sensitivity and selectivity, relative ease of synthesis, production of materials with higher physical robustness, and higher stability, can be extended to more templates that were previously not suitable candidates despite their abundance and usage within the body.

Keywords: molecularly imprinted polymers, specific binding, drug delivery, high biomolecular mass-templates

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Authors: Fatima Muhammad Abdulkadir, D. B. Maikaje, Y. A. Umar

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A study conducted to determine cercariae diversity and prevalence of trematode infection in freshwater snails from six freshwater bodies selected by systematic random sampling in Kaduna State was carried from January 2013 to December 2013. Freshwater snails and cercariae harvested from the study sites were morphologically identified. A total of 23,823 freshwater snails were collected from the six freshwater bodies: Bagoma dam, Gimbawa dam, Kangimi dam, Kubacha dam, Manchok water intake and Saminaka water intake. The observed freshwater snail species were: Melanoides tuberculata, Biomphalaria pfeifferi, Bulinus globosus, Lymnaea natalensis, Physa sp., Cleopatra bulimoides, Bellamya unicolor and Lanistes varicus. The freshwater snails were exposed to artificial bright light from a 100 Watt electric bulb in the laboratory to induce cercarial shedding. Of the total freshwater snails collected, 10.55% released one or more types of cercariae. Seven morphological types of cercariae were shed by six freshwater snail species namely: Brevifurcate-apharyngeate distome, Amphistome, Gymnocephalus, Longifurcate-pharyngeate monostome, Longifurcate-pharyngeate distome, Echinostome and Xiphidio cercariae. Infection was monotype in most of the freshwater snails collected; however, Physa species presented a mixed infection with Gymnocephalus and Longifurcate-pharyngeate distome cercariae. B. globosus and B. pfeifferi were the most preferred intermediate hosts with the prevalence of 13.48% and 13.46%, respectively. The diversity and prevalence of cercariae varied among the six freshwater bodies with Manchok water intake having the highest infestation (14.3%) and the least recorded in Kangimi dam (3.9%). There was a correlation trend between the number of freshwater snails and trematode infection with Manchok exhibiting the highest and Bagoma none. The highest cercarial diversity was observed in B. pfeifferi and B. globosus with four morphotypes each, and the lowest was in M. tuberculata with one morphotype. The general distribution of freshwater snails and the trematode cercariae they shed suggests the risk of human and animals to trematodiasis in Manchok community. Public health education to raise awareness on individual and communal action that may control snail breeding sites, prevent transmission and provide access to treatment should be intensified.

Keywords: Cercariae, diversity, freshwater snails, prevalence, trematodiasis

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Authors: Victoria Masi Haruna Karatu, Nik Kamariah Nikmat

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In recent times awareness about the environment and green purchase has been on the increase across nations due to global warming. Previous researchers have attempted to determine what actually influences the purchase intention of consumers in this environmentally conscious epoch. The consumers too have become conscious of what to buy and who to buy from in their purchasing decisions as this action will reflect their concern about the environment and their personal well-being. This trend is a widespread phenomenon in most developed countries of the world. On the contrary evidence revealed that only 5% of the populations of Nigeria involve in green purchase activities thus making the country lag behind its counterparts in green practices. This is not a surprise as Nigeria is facing problems of inadequate green knowledge, non-enforcement of environmental regulations, sensitivity to the price of green products when compared with the conventional ones and distrust towards green products which has been deduced from prior studies of other regions. The main objectives of this study is to examine the direct antecedents of green purchase intention (green availability, government regulations, perceived green knowledge, perceived value and green price sensitivity) in Nigeria and secondly to establish the mediating role of perceived behavioral control on the relationship between these antecedents and green purchase intention. The study adopts quantitative method whereby 700 questionnaires were administered to lecturers in three Nigerian universities. 502 datasets were collected which represents 72 percent response rate. After screening the data only 440 were usable and analyzed using structural equation modeling (SEM) and bootstrapping. From the findings, three antecedents have significant direct relationships with green purchase intention (perceived green knowledge, perceived behavioral control, and green availability) while two antecedents have positive and significant direct relationship with perceived behavioral control (perceived value and green price sensitivity). On the other hand, PBC does not mediate any of the paths from the predictors to criterion variable. This result is discussed in the Nigerian context.

Keywords: Green Availability, Green Price Sensitivity, Green Purchase Intention, Perceived Green Knowledge, Perceived Value

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Authors: A. K. Asekunowo, A O. T. Asafa, O. O. Okoh, O. T. Asekun, O. B. Familoni

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Background: Acalypha godseffiana is an important plant used both as an ornamental and herbs; its leaves are employed in management of diseases such as diabetics in Eastern Nigeria. Aim: The correlations of the polyphenolic compounds in the hypoglycemic potential of different extracts of leaves of A. godseffiana and their safety profile on cell lines were investigated. Materials and Methods: The phytochemical compositions and antioxidants potentials were determined using adopted methods. An in vitro approach was employed in determining the hypoglycemic potentials of the extracts on α-amylase and α-glucosidase. The Line weaver-Burke plot was used to evaluate the mechanisms of Inhibition mechanisms of the enzymes. Results and Conclusions: Antioxidants results revealed that total antioxidant capacity (TAC) of the acetone extract (IC50: 0.34 mg/mL) showed better activity compared to the standards (silymarine 0.52 mg/mL; gallic acid 0.51 mg/mL). In-vitro hypoglycemic activity of the extracts confirmed that acetone extract demonstrated strong and mild inhibitory potential against α-amylase and α-glucosidase respectively. The observed activity was concentration-dependent with IC50 values of 2.33 and 0.13 mg/mL. The observed hypoglycemic and anti-oxidant potentials of acetone extract A. godseffiana correlate to its high polyphenolic contents which include phenols (133.20 mg gallic acid g-1), flavonoid (350.60 mg quercetin g-1) and tannins (264.67 mg catechin g-1). The mechanisms of action exhibited by acetone extract of A. godseffiana were mixed non-competitive and uncompetitive; which can be attributed to its inhibitory properties on α-amylase and α-glucosidase respectively. This effect would cause reduction in the rate at which starch hydrolyse, boost palliated glucose levels; hence, making acetone extract of A. godseffiana a potential anti-hypoglycemic alternative.

Keywords: Acalypha godeseffiana, acetone extract, anti-hypoglycemia, antioxidant, phytochemicals

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Authors: A. Dean, M. Pitcher, L. Storer, K. Shanahan, I. Rio, B. Mann

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Purpose: Breast cancer survivors are at risk of specific physical and psycho-social issues, such as arm swelling, fatigue, and depression. Firstly, we investigate symptoms reported by Australia breast cancer survivors upon completion of definitive treatment. Secondly, we evaluate the appropriateness and effectiveness of a multi-centre pilot program nurse-led clinic to identify these issues and make timely referrals to available services. Methods: Patients post-definitive treatment (excluding ongoing hormonal therapy) for early breast cancer or ductal carcinoma in situ were invited to participate. An hour long appointment with a breast care nurse (BCN) was scheduled. In preparation, patients completed validated quality-of-life surveys (FACT-B, Menopause Rating Scale, Distress Thermometer). During the appointment, issues identified in the surveys were addressed and referrals to appropriate services arranged. Results: 183 of 274 (67%) eligible patients attended a nurse-led clinic. Mean age 56.8 years (range 29-87 years), 181/183 women, 105/183 post-menopausal. 96 (55%) participants reported significant level of distress; 31 (18%) participants reported extreme distress or depression. Distress stemmed from a lack of energy (56/175); poor quality of sleep (50/176); inability to work or participate in household activities (35/172) and problems with sex life (28/89). 166 referrals were offered; 94% of patients accepted the referrals. 65% responded to a follow-up survey: the majority of women either strongly agreed or agreed that the BCN was overwhelmingly supportive, helpful in making referrals, and compassionate towards them. 39% reported making lifestyle changes as a result of the BCN. Conclusion: Breast cancer survivors experience a unique set of challenges, including low mood, difficulty sleeping, problems with sex life and fear of disease recurrence. The nurse-led clinic model is an appropriate and effective method to ensure physical and psycho-social issues are identified and managed in a timely manner. This model empowers breast cancer survivors with information about their diagnosis and available services.

Keywords: early breast cancer, survivorship, breast care nursing, oncology nursing and cancer care

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Authors: Wen-Chyan Tsai, Syed S. H. Rizvi

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Organic solvent residues are always associated with liposomes produced by the traditional techniques like the thin film hydration and reverse phase evaporation methods, which limit the applications of these vesicles in the pharmaceutical, food and cosmetic industries. Our objective was to develop a novel and benign process of liposomal microencapsulation by using supercritical carbon dioxide (SC-CO2) as the sole phospholipid-dissolving medium and a green substitute for organic solvents. This process consists of supercritical fluid extraction followed by rapid expansion via a nozzle and automatic cargo suction. Lecithin and cholesterol mixed in 10:1 mass ratio were dissolved in SC-CO2 at 20 ± 0.5 MPa and 60 oC. After at least two hours of equilibrium, the lecithin/cholesterol-laden SC-CO2 was passed through a 1000-micron nozzle and immediately mixed with the cargo solution to form liposomes. Liposomal micro-encapsulation was conducted at three pressures (8.27, 12.41, 16.55 MPa), three temperatures (75, 83 and 90 oC) and two flow rates (0.25 ml/sec and 0.5 ml/sec). Liposome size, zeta potential and encapsulation efficiency were characterized as functions of the operating parameters. The average liposomal size varied from 400-500 nm to 1000-1200 nm when the pressure was increased from 8.27 to 16.55 MPa. At 12.41 MPa, 90 oC and 0.25 ml per second of 0.2 M glucose cargo loading rate, the highest encapsulation efficiency of 31.65 % was achieved. Under a confocal laser scanning microscope, large unilamellar vesicles and multivesicular vesicles were observed to make up a majority of the liposomal emulsion. This new approach is a rapid and continuous process for bulk production of liposomes using a green solvent. Based on the results to date, it is feasible to apply this technique to encapsulate hydrophilic compounds inside the aqueous core as well as lipophilic compounds in the phospholipid bilayers of the liposomes for controlled release, solubility improvement and targeted therapy of bioactive compounds.

Keywords: liposome, micro encapsulation, supercritical carbon dioxide, non-toxic process

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Authors: Ayobami Solomon Popoola

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Yam is majorly a carbohydrate food grown in most parts of the world. It could be boiled, fried or roasted for consumption in a variety of ways. Blanching is an established heat pre-treatment given to fruits and vegetables prior to further processing such as dehydration, canning, freezing etc. Losses of soluble solids during blanching has been a great problem because a reasonable quantity of the water-soluble nutrients are inevitably leached into the blanching water. Without blanching, the high residual levels of reducing sugars after extended storage produce a dark, bitter-tasting product because of the Maillard reactions of reducing sugars at frying temperature. Measurement and prediction of such losses are necessary for economic efficiency in production and to establish the level of effluent treatment of the blanching water. This paper aims at resolving this problem by investigating the effects of cube size and temperature on the rate of diffusional losses of reducing sugars and total sugars during hot water blanching of water-yam. The study was carried out using four temperature levels (65, 70, 80 and 90 °C) and two cubes sizes (0.02 m³ and 0.03 m³) at 4 times intervals (5, 10, 15 and 20 mins) respectively. Obtained data were fitted into Fick’s non-steady equation from which diffusion coefficients (Da) were obtained. The Da values were subsequently fitted into Arrhenius plot to obtain activation energies (Ea-values) for diffusional losses. The diffusion co-efficient were independent of cube size and time but highly temperature dependent. The diffusion coefficients were ≥ 1.0 ×10⁻⁹ m²s⁻¹ for reducing sugars and ≥ 5.0 × 10⁻⁹ m²s⁻¹ for total sugars. The Ea values ranged between 68.2 to 73.9 KJmol⁻¹ and 7.2 to 14.30 KJmol⁻¹ for reducing sugars and total sugars losses respectively. Predictive equations for estimating amount of reducing sugars and total sugars with blanching time of water-yam at various temperatures were also presented. The equation could be valuable in process design and optimization. However, amount of other soluble solids that might have leached into the water along with reducing and total sugars during blanching was not investigated in the study.

Keywords: blanching, kinetics, sugar losses, water yam

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Authors: Tumelo Jaquiline Ntsopi

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This study explored the academic writing challenges of first-year students who use English as an Additional Language (EAL) registered in the EAW101 module at an ODeL institution. Research shows that academic writing is a challenge for EAL teaching and learning contexts across the globe in higher education institutions (HEIs). Academic writing is an important aspect of academic literacy in any institution of higher learning, more so in an ODeL institution. This has probed research that shows that academic writing is and continues to pose challenges for EAL teaching and learning contexts in higher education institutions. This study stems from the researcher’s experience in teaching academic writing to first-year students in the EAW101 module. The motivation for this study emerged from the fact that EAW101 is a writing module that has a high number of students in the Department of English Studies with an average of between 50-80 percent pass rate. These statistics elaborate on the argument that most students registered in this module struggle with academic writing, and they need intervention to assist and support them in achieving competence in the module. This study is underpinned by Community of Inquiry (CoI) framework and Transactional distance theory. This study adopted a qualitative research methodology and utilised a case study approach as a research design. Furthermore, the study gathered data from first year students and the EAW101 module’s student support initiatives. To collect data, focus group discussions, structured open-ended evaluation questions, and an observation schedule were used to gather data. The study is vital towards exploring academic writing challenges that first-year students in EAW101 encounter so that lecturers in the module may consider re-evaluating their methods of teaching to improve EAL students’ academic writing skills. This study may help lecturers towards enhancing academic writing in a ODeL context by assisting first year students through using student support interventions.

Keywords: academic writing, academic writing challenge, ODeL, EAL

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Authors: Farahnaz Karami

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Routing is an important, challenging task in mobile ad hoc networks due to node mobility, lack of central control, unstable links, and limited resources. An ant colony has been found to be an attractive technique for routing in Mobile Ad Hoc Networks (MANETs). However, existing swarm intelligence based routing protocols find an optimal path by considering only one or two route selection metrics without considering correlations among such parameters making them unsuitable lonely for routing real time applications. Fuzzy logic combines multiple route selection parameters containing uncertain information or imprecise data in nature, but does not have multipath routing property naturally in order to provide load balancing. The objective of this paper is to design a routing algorithm using fuzzy logic and ant colony that can solve some of routing problems in mobile ad hoc networks, such as nodes energy consumption optimization to increase network lifetime, link failures rate reduction to increase packet delivery reliability and providing load balancing to optimize available bandwidth. In proposed algorithm, the path information will be given to fuzzy inference system by ants. Based on the available path information and considering the parameters required for quality of service (QoS), the fuzzy cost of each path is calculated and the optimal paths will be selected. NS2.35 simulation tools are used for simulation and the results are compared and evaluated with the newest QoS based algorithms in MANETs according to packet delivery ratio, end-to-end delay and routing overhead ratio criterions. The simulation results show significant improvement in the performance of these networks in terms of decreasing end-to-end delay, and routing overhead ratio, and also increasing packet delivery ratio.

Keywords: mobile ad hoc networks, routing, quality of service, ant colony, fuzzy logic

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Authors: Charirat Kusonwiriyawong, Supha Photichan, Wannarut Chutibutr

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Soil test kits for rapid analysis of the organic matter, available phosphorus and exchangeable potassium were developed to drive a low-cost field testing kit to farmers. The objective was to provide a decision tool for improving soil fertility. One aspect of soil test kit development was ease of use which is a time requirement for completing organic matter, available phosphorus and exchangeable potassium test in one soil sample. This testing kit required only two extractions and utilized no filtration consuming approximately 15 minutes per sample. Organic matter was principally created by oxidizing carbon KMnO₄ using the standard color chart. In addition, modified single extractant (Mehlich I) was applied to extract available phosphorus and exchangeable potassium. Molybdenum blue method and turbidimetric method using standard color chart were adapted to analyze available phosphorus and exchangeable potassium, respectively. Modified single extractant using in soil test kits were highly significant matching with analytical laboratory results (r=0.959** and 0.945** for available phosphorus and exchangeable potassium, respectively). Linear regressions were statistically calculated between modified single extractant and standard laboratory analysis (y=0.9581x-12.973 for available phosphorus and y=0.5372x+15.283 for exchangeable potassium, respectively). These equations were calibrated to formulate a fertilizer rate recommendation for specific corps. To validate quality, soil test kits were distributed to farmers and extension workers. We found that the accuracy of soil test kits were 71.0%, 63.9% and 65.5% for organic matter, available phosphorus, and exchangeable potassium, respectively. The quantitative survey was also conducted in order to assess their satisfaction with soil test kits. The survey showed that more than 85% of respondents said these testing kits were more convenient, economical and reliable than the other commercial soil test kits. Based upon the finding of this study, soil test kits can be another alternative for providing soil analysis and fertility recommendations when a soil testing laboratory is not available.

Keywords: available phosphorus, exchangeable potassium, modified single extractant, organic matter, soil test kits

Procedia PDF Downloads 126

Authors: Hamidreza Khodaei, Ali Daryabeigi Zand

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Ovulation is a physiologic process with an inflammatory response that depends on a coordinated activity of gonadotropins and steroid hormones, and inflammatory mediators such as cytokines, prostaglandins, leptin, nitric oxide (NO), etc. Conjugated linoleic acid (CLA) is composed of polyunsaturated fatty acids (PUFA) found in dairy products, beef, and lamb. There is strong evidence that dietary CLA affects mediators involved in ovulation. The objective of this study is to evaluate the impacts of various doses of dietary CLA on systemic and local hormones and parameters involved in ovulation. In this case-control research, 80 (50 ± 2-day old) female mice were randomly divided into 4 groups (C as control treatment and T1, T2 and T3 are considered as the treatment groups). There were four replicates in each group, and there were five mice in every replicate (20 mice, in total). The mice in the control group were fed with no CLA in their diet, but the ones in the treatment group received 0.1, 0.3 and 0.5g/kg of CLA (replacing corn oil in the diet), respectively for four months. After that, blood samples were obtained from the tails of animals that displayed estrus signs and estradiol (E2), progesterone (P4), LH, FSH, NO, leptin and TNFα were measured. In addition, the impacts of CLA on the ovarian production of prostaglandins (PGs) and NO were studied. The data were analyzed by SAS software. CLA considerably decreased serum levels of FSH (p < 0.05), LH, estradiol, NO, leptin and TNFα (p < 0.01). In addition, CLA decreased progesterone levels, but this effect was statistically not significant. The significantly adverse effects of CLA were observed in the ovarian production of PGE2 and PGF2α (p < 0.01). It seems that CLA may play an important role in reducing the ovulation rate in mice as CLA negatively affected female reproduction and it had adverse effects on systemic and local hormones involved in ovulation.

Keywords: conjugated linoleic acid, nitric oxide, ovary, ovulation, prostaglandin, gonadotropin

Procedia PDF Downloads 197

Authors: Moh’d A. AL-Shboul

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Recently, and due to Arab spring and terrorism around the globe, pushing and driving most governments potentially to harmonize their border measures particularly the regional and an international transit trade within and among Customs Unions. The main purpose of this study is to investigate and provide an insight for monitoring and controlling the trade supply chain within and among different countries by using technological advancement (i.e. an electronic tracking system, etc.); furthermore, facilitate the local and intra-regional trade among countries through reviewing the recent trends and practical implementation of an electronic transit traffic and cargo that related to customs measures by introducing and supporting some case studies of several international and landlocked transit trade countries. The research methodology employed in this study was described as qualitative by conducting few interviews with managers, transit truck drivers, and traders and reviewing the related literature to collect qualitative data from secondary sources such as statistical reports, previous studies, etc. The results in this study show that Jordan and other countries around the globe that used an electronic tracking system for monitoring transit trade has led to a significant reduction in cost, effort and time in physical movement of goods internally and crossing through other countries. Therefore, there is no need to escort transit trucks by customs staff; hence, the rate of escort transit trucks is reduced by more than ninety percent, except the bulky and high duty goods. Electronic transit traffic has been increased; the average transit time journey has been reduced by more than seventy percent and has led to decrease in rates of smuggling up to fifty percent. The researcher recommends considering Jordan as regional and international office for tracking electronically and monitoring the transit trade for many considerations.

Keywords: electronic tracking system, facilitation system, regional and international corridor, supply chain security, transit trade

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Authors: Amalia Ardeljan, Lexi Frankel, Divesh Manjani, Gabriela Santizo, Maximillian Guerra, Omar Rashid

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Introduction: Cytomegalovirus (CMV) infection is a widespread infection affecting between 60-70% of people in industrialized countries. CMV has been previously correlated with a higher incidence of Hodgkin Lymphoma compared to noninfected persons. Research regarding prior CMV infection and subsequent lymphoma development is still controversial. With limited evidence, further research is needed in order to understand the relationship between previous CMV infection and subsequent lymphoma development. This study assessed the effect of CMV infection and the incidence of lymphoma afterward. Methods: A retrospective cohort study (2010-2019) was conducted through a Health Insurance Portability and Accountability Act (HIPAA) compliant national database and conducted using International Classification of Disease (ICD) 9th,10th codes, and Current Procedural Terminology (CPT) codes. These were used to identify lymphoma diagnosis in a previously CMV infected population. Patients were matched for age range and Charlson Comorbidity Index (CCI). A chi-squared test was used to assess statistical significance. Results: A total number of 14,303 patients was obtained in the CMV infected group as well as in the control population (matched by age range and CCI score). Subsequent lymphoma development was seen at a rate of 11.44% (1,637) in the CMV group and 5.74% (822) in the control group, respectively. The difference was statistically significant by p= 2.2x10-16, odds ratio = 2.696 (95% CI 2.483- 2.927). In an attempt to stratify the population by antiviral medication exposure, the outcomes were limited by the decreased number of members exposed to antiviral medication in the control population. Conclusion: This study shows a statistically significant correlation between prior CMV infection and an increased incidence of lymphoma afterward. Further exploration is needed to identify the potential carcinogenic mechanism of CMV and whether the results are attributed to a confounding bias.

Keywords: cytomegalovirus, lymphoma, cancer, microbiology

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Authors: Liong-Rung Liu, Yu-Hui Chiu, Wen-Han Chang

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Firearm injuries are high-energy injuries. The ballistic pathways could cause severe burns or chemical damages to vessels, musculoskeletal or other major organs. The high mortality rate is accompanied by complications such as sepsis. As laws prohibit gun possession, civilian gunshot wounds (GSW) are relatively rare in Taiwan. Our hospital, Mackay Memorial Hospital, located at the center of Taipei city is surrounded by nightclubs and red-light districts. Due to this unique location, our hospital becomes the first-line trauma center managing gunshot victims in Taiwan. To author’s best knowledge, there are few published research articles regarding this unique situation. We hereby analyze the distinct characteristics and length of stay (LOS) of GSW patients in the emergency room (ER) at Mackay Memorial Hospital. A 6-year retrospective analysis of 27 patients treated for GSW injuries from January 2012 to December 2017 was performed. The patients’ records were reviewed for the following analyses, 1) wound position and the correlated clinical presentations; 2) the LOS in ED of patients receiving emergency surgery for major organ or vascular injuries. We found males (96.3%) were injured by guns more often than females (3.7%) in all age groups. The most common injured site was in the extremities. With regards to the ER LOS, the average time were 72.2 ± 34.5 minutes for patients with triage I and 207.4 ± 143.9 minutes for patients with triage II. The ED LOS of patients whose ISS score were more than 15 was 59.9 ± 25.6 minutes, and 179.4 ± 119.8 minutes for patients whose ISS score were between 9 to 15, respectively. Among these 27 patients, 10 patients had emergency surgery and their average ED stay time was 104.5 ± 33.3 minutes. Even more, the average ED stay time could be shortened to 88.8 ± 32.3 minutes in the 5 patients with trauma team activation. In conclusion, trauma team activation in severe GSW patients indeed shortens the ED LOS and might initially improve the quality of patient care. This is the result of better trauma systems, including advances in care from emergency medical services and acute care surgical management.

Keywords: gunshot, length of stay, trauma, mortality

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Authors: Dmytro Zubov, Francesco Volponi

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In this paper, D-Wave quantum computing Ising model is used for the forecasting of positive extremes of daily mean air temperature. Forecast models are designed with two to five qubits, which represent 2-, 3-, 4-, and 5-day historical data respectively. Ising model’s real-valued weights and dimensionless coefficients are calculated using daily mean air temperatures from 119 places around the world, as well as sea level (Aburatsu, Japan). In comparison with current methods, this approach is better suited to predict heat wave values because it does not require the estimation of a probability distribution from scarce observations. Proposed forecast quantum computing algorithm is simulated based on traditional computer architecture and combinatorial optimization of Ising model parameters for the Ronald Reagan Washington National Airport dataset with 1-day lead-time on learning sample (1975-2010 yr). Analysis of the forecast accuracy (ratio of successful predictions to total number of predictions) on the validation sample (2011-2014 yr) shows that Ising model with three qubits has 100 % accuracy, which is quite significant as compared to other methods. However, number of identified heat waves is small (only one out of nineteen in this case). Other models with 2, 4, and 5 qubits have 20 %, 3.8 %, and 3.8 % accuracy respectively. Presented three-qubit forecast model is applied for prediction of heat waves at other five locations: Aurel Vlaicu, Romania – accuracy is 28.6 %; Bratislava, Slovakia – accuracy is 21.7 %; Brussels, Belgium – accuracy is 33.3 %; Sofia, Bulgaria – accuracy is 50 %; Akhisar, Turkey – accuracy is 21.4 %. These predictions are not ideal, but not zeros. They can be used independently or together with other predictions generated by different method(s). The loss of human life, as well as environmental, economic, and material damage, from extreme air temperatures could be reduced if some of heat waves are predicted. Even a small success rate implies a large socio-economic benefit.

Keywords: heat wave, D-wave, forecast, Ising model, quantum computing

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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

Procedia PDF Downloads 207

Authors: Shaista Suhail

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As cancer populations is increasing sharply, the incidence of oral squamous cell carcinoma (OSCC) has also been expected to increase. Oral carcinogenesis is a highly complex, multistep process which involves accumulation of genetic alterations that lead to the induction of proteins promoting cell growth (encoded by oncogenes), increased enzymatic (telomerase) activity promoting cancer cell proliferation. The global increase in frequency and mortality, as well as the poor prognosis of oral squamous cell carcinoma, has intensified current research efforts in the field of prevention and early detection of this disease. The advances in the understanding of the molecular basis of oral cancer should help in the identification of new markers. The study of the carcinogenic process of the oral cancer, including continued analysis of new genetic alterations, along with their temporal sequencing during initiation, promotion and progression, will allow us to identify new diagnostic and prognostic factors, which will provide a promising basis for the application of more rational and efficient treatments. Telomerase activity has been readily found in most cancer biopsies, in premalignant lesions or germ cells. Activity of telomerase is generally absent in normal tissues. It is known to be induced upon immortalization or malignant transformation of human cells such as in oral cancer cells. Maintenance of telomeres plays an essential role during transformation of precancer to malignant stage. Mammalian telomeres, a specialized nucleoprotein structures are composed of large conctamers of the guanine-rich sequence 5_-TTAGGG-3_. The roles of telomeres in regulating both stability of genome and replicative immortality seem to contribute in essential ways in cancer initiation and progression. It is concluded that activity of telomerase can be used as a biomarker for diagnosis of malignant oral cancer and a target for inactivation in chemotherapy or gene therapy. Its expression will also prove to be an important diagnostic tool as well as a novel target for cancer therapy. The activation of telomerase may be an important step in tumorgenesis which can be controlled by inactivating its activity during chemotherapy. The expression and activity of telomerase are indispensable for cancer development. There are no drugs which can effect extremely to treat oral cancers. There is a general call for new emerging drugs or methods that are highly effective towards cancer treatment, possess low toxicity, and have a minor environment impact. Some novel natural products also offer opportunities for innovation in drug discovery. Natural compounds isolated from medicinal plants, as rich sources of novel anticancer drugs, have been of increasing interest with some enzyme (telomerase) blockage property. The alarming reports of cancer cases increase the awareness amongst the clinicians and researchers pertaining to investigate newer drug with low toxicity.

Keywords: oral carcinoma, telomere, telomerase, blockage

Procedia PDF Downloads 158

Authors: Lubaina Soni, Claire Farrell, Christopher Szota, Tim D. Fletcher

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Green roofs are a promising engineered ecosystem for reducing stormwater runoff and restoring vegetation cover in cities. Plants can contribute to rainfall retention by rapidly depleting water in the substrate; however, this increases the risk of plant drought stress. Green roof configurations, therefore, need to provide plants the opportunity to efficiently deplete the substrate but also avoid severe drought stress. This study used green roof modules placed in a rainout shelter during a six-month rainfall regime simulated in Melbourne, Australia. Rainfall was applied equally with an overhead irrigation system on each module. Aside from rainfall, modules were under natural climatic conditions, including temperature, wind, and radiation. A single species, Ficinia nodosa, was planted with five different treatments and three replicates of each treatment. In this experiment, we tested the impact of three plant cover treatments (0%, 50% and 100%) on rainfall retention and plant drought stress. We also installed two runoff zone treatments covering 50% of the substrate surface for additional modules with 0% and 50% plant cover to determine whether directing rainfall resources towards plant roots would reduce drought stress without impacting rainfall retention. The retention performance for the simulated rainfall events was measured, quantifying all components for hydrological performance and survival on green roofs. We found that evapotranspiration and rainfall retention were similar for modules with 50% and 100% plant cover. However, modules with 100% plant cover showed significantly higher plant drought stress. Therefore, planting at a lower cover/density reduced plant drought stress without jeopardizing rainfall retention performance. Installing runoff zones marginally reduced evapotranspiration and rainfall retention, but by approximately the same amount for modules with 0% and 50% plant cover. This indicates that reduced evaporation due to the installation of the runoff zones likely contributed to reduced evapotranspiration and rainfall retention. Further, runoff occurred from modules with runoff zones faster than those without, indicating that we created a faster pathway for water to enter and leave the substrate, which also likely contributed to lower overall evapotranspiration and retention. However, despite some loss in retention performance, modules with 50% plant cover installed with runoff zones showed significantly lower drought stress in plants compared to those without runoff zones. Overall, we suggest that reducing plant cover represents a simple means of optimizing green roof performance but creating runoff zones may reduce plant drought stress at the cost of reduced rainfall retention.

Keywords: green roof, plant cover, plant drought stress, rainfall retention

Procedia PDF Downloads 104

Authors: Idit Kalisher, Israel Luski

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One result of the growing dynamicity of labor markets in recent decades is a wider scope of employment mobility – i.e., transitions between employers, either within or between careers. Employment mobility decisions are primarily affected by the current employment status of the worker, which is reflected in wage and tenure. Using 34,328 observations from the National Longitudinal Survey of Youth 1979 (NLS79), which were derived from the USA population between 1990 and 2012, this paper aims to investigate the effects of wage and tenure over employment mobility choices, and additionally to examine the effects of other personal characteristics, individual labor market characteristics and macroeconomic factors. The estimation strategy was designed to address two challenges that arise from the combination of the model and the data: (a) endogeneity of the wage and the tenure in the choice equation; and (b) unobserved heterogeneity, as the data of this research is longitudinal. To address (a), estimation was performed using two-stage limited dependent variable procedure (2SLDV); and to address (b), the second stage was estimated using femlogit – an implementation of the multinomial logit model with fixed effects. Among workers who have experienced at least one turnover, the wage was found to have a main effect on career turnover likelihood of all workers, whereas the wage effect on job turnover likelihood was found to be dependent on individual characteristics. The wage was found to negatively affect the turnover likelihood and the effect was found to vary across wage level: high-wage workers were more affected compared to low-wage workers. Tenure was found to have a main positive effect on both turnover types’ likelihoods, though the effect was moderated by the wage. The findings also reveal that as their wage increases, women are more likely to turnover than men, and academically educated workers are more likely to turnover within careers. Minorities were found to be as likely as Caucasians to turnover post wage-increase, but less likely to turnover with each additional tenure year. The wage and the tenure effects were found to vary also between careers. The difference in attitude towards money, labor market opportunities and risk aversion could explain these findings. Additionally, the likelihood of a turnover was found to be affected by previous unemployment spells, age, and other labor market and personal characteristics. The results of this research could assist policymakers as well as business owners and employers. The former may be able to encourage women and older workers’ employment by considering the effects of gender and age on the probability of a turnover, and the latter may be able to assess their employees’ likelihood of a turnover by considering the effects of their personal characteristics.

Keywords: employment mobility, endogeneity, femlogit, turnover

Procedia PDF Downloads 135

Authors: Jonathan Magala

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Context: Adolescents in Uganda face significant challenges related to sexual health due to inadequate sexual information. This lack of information puts young people at risk of early pregnancies, sexually transmitted infections, and poverty. Therefore, it is essential to understand the sources, content, and challenges of acquiring sexual information among secondary school-going adolescents in Uganda. Research Aim: The aim of this study was to establish the sources, content, and challenges of acquiring sexual information among secondary school-going adolescents in Luwero Town Council, Uganda. Methodology: This study used a cross-sectional approach with both qualitative and quantitative methods. Questionnaires and in-depth interviews were conducted with 384 school-going adolescents aged between 13-19 years in Luwero Town Council, Uganda. Findings: The results of the study revealed that adolescents receive sexual information from various sources, with schools being the most common source, followed by parents and religious institutions being the least utilized. Adolescents received information on various topics related to sexuality, including puberty and sexual changes, pregnancy and reproduction, STD information, abstinence, and family planning. However, the content of sexual information was inadequate in addressing the challenges facing adolescents, and there were generation gaps, lack of role models, peer influence, and government policies. The male character from all the sources was the least in offering sexual information to adolescents. Theoretical Importance: The study's findings highlight the need for policy implementation to strengthen sexual education in school curriculum, as the sources of sexual information and the content are inadequate. The various topics should be addressed in schools to provide comprehensive education on sexual health for adolescents. Data Collection and Analysis Procedures: Data collection involved questionnaires and in-depth interviews with school-going adolescents. The data gathered were analyzed using descriptive statistics and thematic analysis. Questions Addressed: The study aimed to answer questions about the sources of sexual information among school-going adolescents, the content of sexual information provided, the challenges faced in accessing the information, and the importance of sex education policy implementation. Conclusion: The study concludes that schools are a popular source of sexual information among school-going adolescents in Uganda. However, the content of the information provided is inadequate in addressing the challenges that adolescents face regarding their sexual health. Therefore, policy implementation is essential in strengthening sexual education in the school curriculum and addressing various topics related to sexual health.

Keywords: adolescents, sexual information, schools, reproductive health

Procedia PDF Downloads 63

Authors: Richard Renou, Laurent Soulard

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Lasers are widely used in glass material processing, from waveguide fabrication to channel drilling. The gradual damage of glass optics under UV lasers is also an important issue to be addressed. Glass materials (including metallic glasses) can undergo a permanent densification under laser-induced shock loading. Despite increased interest on interactions between laser and glass materials, little is known about the structural mechanisms involved under shock loading. For example, the densification process in silica glasses occurs between 8 GPa and 30 GPa. Above 30 GPa, the glass material returns to the original density after relaxation. Investigating these unusual mechanisms in silica glass will provide an overall better understanding in glass behaviour. Non-Equilibrium Molecular Dynamics simulations (NEMD) were carried out in order to gain insight on the silica glass microscopic structure under shock loading. The shock was generated by the use of a piston impacting the glass material at high velocity (from 100m/s up to 2km/s). Periodic boundary conditions were used in the directions perpendicular to the shock propagation to model an infinite system. One-dimensional shock propagations were therefore studied. Simulations were performed with the STAMP code developed by the CEA. A very specific structure is observed in a silica glass. Oxygen atoms around Silicon atoms are organized in tetrahedrons. Those tetrahedrons are linked and tend to form rings inside the structure. A significant amount of empty cavities is also observed in glass materials. In order to understand how a shock loading is impacting the overall structure, the tetrahedrons, the rings and the cavities were thoroughly analysed. An elastic behaviour was observed when the shock pressure is below 8 GPa. This is consistent with the Hugoniot Elastic Limit (HEL) of 8.8 GPa estimated experimentally for silica glasses. Behind the shock front, the ring structure and the cavity distribution are impacted. The ring volume is smaller, and most cavities disappear with increasing shock pressure. However, the tetrahedral structure is not affected. The elasticity of the glass structure is therefore related to a ring shrinking and a cavity closing. Above the HEL, the shock pressure is high enough to impact the tetrahedral structure. An increasing number of hexahedrons and octahedrons are formed with the pressure. The large rings break to form smaller ones. The cavities are however not impacted as most cavities are already closed under an elastic shock. After the material relaxation, a significant amount of hexahedrons and octahedrons is still observed, and most of the cavities remain closed. The overall ring distribution after relaxation is similar to the equilibrium distribution. The densification process is therefore related to two structural mechanisms: a change in the coordination of silicon atoms and a cavity closing. To sum up, non-equilibrium molecular dynamics were carried out to investigate silica behaviour under shock loading. Analysing the structure lead to interesting conclusions upon the elastic and the densification mechanisms in glass materials. This work will be completed with a detailed study of the mechanism occurring above 30 GPa, where no sign of densification is observed after the material relaxation.

Keywords: densification, molecular dynamics simulations, shock loading, silica glass

Procedia PDF Downloads 213