Search results for: generalized topology

Authors: Naim Izet Kajtazi

Abstract:

Context: The third ventricle colloid cyst (CC) is a benign growth usually located in the third ventricle and can cause various neurological symptoms, including sudden death. Modern surgical interventions may still result in a wide range of complications and cerebral venous thrombosis (CVT) is among them. Process: A 38-year-old female with an existing diagnosis of diabetes mellitus (DM) and hypothyroidism and a six-month history of headaches, blurred vision, and vomiting presented to our clinic three days after the headaches became excessively severe. Neurological examination on admission revealed bilateral papilledema without any associated focal neurological deficits. Brain computed tomography (CT) and magnetic resonance imaging (MRI) confirmed the presence of a third ventricle colloid cyst and associated non-communicating hydrocephalus involving the lateral ventricles. As a result, the patient underwent emergency bilateral external ventricular drainage (EVD) insertion followed by a third ventricular CC excision under neuronavigation through a right frontal craniotomy. Twelve days post-operatively, the patient developed further headaches, followed by a generalized tonic-clonic seizure that led to no postictal neurological deficits. Nonetheless, computed tomography venography of the brain revealed extensive thrombosis of the superior sagittal sinus, inferior sagittal sinus, right sigmoid sinus, and right internal jugular vein. A newly diagnosed CVT was treated with intravenous heparin. The patient was discharged with warfarin, which was discontinued after 12 months. Ten years after her illness, she remained stable and free from any neurological deficits but still suffered from mild chronic headaches. Outcome: Ten years after her illness, she remained stable and free from any neurological deficits but still suffered from mild chronic headaches. Relevance: A preoperative venous study should be performed in all cases to gain a better understanding of the venous anatomy. We advocate meticulous microsurgical techniques to protect the venous system surrounding the foramen of Monro and reduce the amount of retraction during surgery.

Keywords: CVT, seizures, third ventricle colloid cyst, MRI of brain

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Authors: Tanmaya Pradhan, K. Midhun, M. Joy Thomas

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Increasing the shelf life and improving the quality are important objectives for the success of packaged liquid food industry. One of the methods by which this can be achieved is by deactivating the micro-organisms present in the liquid food through pasteurization. Pasteurization is done by heating, but some serious disadvantages such as the reduction in food quality, flavour, taste, colour, etc. were observed because of heat treatment, which leads to the development of newer methods instead of pasteurization such as treatment using UV radiation, high pressure, nuclear irradiation, pulsed electric field, etc. In recent years the use of the pulsed electric field (PEF) for inactivation of the microbial content in the food is gaining popularity. PEF uses a very high electric field for a short time for the inactivation of microorganisms, for which we require a high voltage pulsed power source. Pulsed power sources used for PEF treatments are usually in the range of 5kV to 50kV. Different pulse shapes are used, such as exponentially decaying and square wave pulses. Exponentially decaying pulses are generated by high power switches with only turn-on capacity and, therefore, discharge the total energy stored in the capacitor bank. These pulses have a sudden onset and, therefore, a high rate of rising but have a very slow decay, which yields extra heat, which is ineffective in microbial inactivation. Square pulses can be produced by an incomplete discharge of a capacitor with the help of a switch having both on/off control or by using a pulse forming network. In this work, a pulsed power-based system is designed with the help of high voltage capacitors and solid-state switches (IGBT) for the inactivation of pathogenic micro-organism in liquid food such as fruit juices. The high voltage generator is based on the Marx generator topology, which can produce variable amplitude, frequency, and pulse width according to the requirements. Liquid food is treated in a chamber where pulsed electric field is produced between stainless steel electrodes using the pulsed output voltage of the supply. Preliminary bacterial inactivation tests were performed by subjecting orange juice inoculated with Escherichia Coli bacteria. With the help of the developed pulsed power source and the chamber, the inoculated orange has been PEF treated. The voltage was varied to get a peak electric field up to 15kV/cm. For a total treatment time of 200µs, a 30% reduction in the bacterial count has been observed. The detailed results and analysis will be presented in the final paper.

Keywords: Escherichia coli bacteria, high voltage generator, microbial inactivation, pulsed electric field, pulsed forming line, solid-state switch

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Authors: Dino Carpentras, Alejandro Dinkelberg, Michael Quayle

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Within agent-based modeling, opinion dynamics is the field that focuses on modeling people's opinions. In this prolific field, most of the literature is dedicated to the exploration of the two 'degrees of freedom' and how they impact the model’s properties (e.g., the average final opinion, the number of final clusters, etc.). These degrees of freedom are (1) the interaction rule, which determines how agents update their own opinion, and (2) the network topology, which defines the possible interaction among agents. In this work, we show that the third degree of freedom exists. This can be used to change a model's output up to 100% of its initial value or to transform two models (both from the literature) into each other. Since opinion dynamics models are representations of the real world, it is fundamental to understand how people’s opinions can be measured. Even for abstract models (i.e., not intended for the fitting of real-world data), it is important to understand if the way of numerically representing opinions is unique; and, if this is not the case, how the model dynamics would change by using different representations. The process of measuring opinions is non-trivial as it requires transforming real-world opinion (e.g., supporting most of the liberal ideals) to a number. Such a process is usually not discussed in opinion dynamics literature, but it has been intensively studied in a subfield of psychology called psychometrics. In psychometrics, opinion scales can be converted into each other, similarly to how meters can be converted to feet. Indeed, psychometrics routinely uses both linear and non-linear transformations of opinion scales. Here, we analyze how this transformation affects opinion dynamics models. We analyze this effect by using mathematical modeling and then validating our analysis with agent-based simulations. Firstly, we study the case of perfect scales. In this way, we show that scale transformations affect the model’s dynamics up to a qualitative level. This means that if two researchers use the same opinion dynamics model and even the same dataset, they could make totally different predictions just because they followed different renormalization processes. A similar situation appears if two different scales are used to measure opinions even on the same population. This effect may be as strong as providing an uncertainty of 100% on the simulation’s output (i.e., all results are possible). Still, by using perfect scales, we show that scales transformations can be used to perfectly transform one model to another. We test this using two models from the standard literature. Finally, we test the effect of scale transformation in the case of finite precision using a 7-points Likert scale. In this way, we show how a relatively small-scale transformation introduces both changes at the qualitative level (i.e., the most shared opinion at the end of the simulation) and in the number of opinion clusters. Thus, scale transformation appears to be a third degree of freedom of opinion dynamics models. This result deeply impacts both theoretical research on models' properties and on the application of models on real-world data.

Keywords: degrees of freedom, empirical validation, opinion scale, opinion dynamics

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Authors: Julio Jesus Salazar, Max Jesus De Lama

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The challenges of water management are aggravated by global change, which implies high complexity and associated uncertainty; water management is difficult because water networks cross domains (natural, societal, and political), scales (space, time, jurisdictional, institutional, knowledge, etc.) and levels (area: patches to global; knowledge: a specific case to generalized principles). In this context, we need to apply natural and non-natural measures to manage water and soil. The Basin Management Methodology considers multifunctional measures of natural water retention and erosion control and soil formation to protect water resources and address the challenges related to the recovery or conservation of the ecosystem, as well as natural characteristics of water bodies, to improve the quantitative status of water bodies and reduce vulnerability to floods and droughts. This method of water management focuses on the positive impacts of the chemical and ecological status of water bodies, restoration of the functioning of the ecosystem and its natural services; thus, contributing to both adaptation and mitigation of climate change. This methodology was applied in 7 interventions in the sub-basin of the Shullcas River in Huancayo-Junín-Peru, obtaining great benefits in the framework of the participation of alliances of actors and integrated planning scenarios. To implement the methodology in the sub-basin of the Shullcas River, a process called Climate Smart Territories (CST) was used; with which the variables were characterized in a highly complex space. The diagnosis was then worked using risk management and adaptation to climate change. Finally, it was concluded with the selection of alternatives and projects of this type. Therefore, the CST approach and process face the challenges of climate change through integrated, systematic, interdisciplinary and collective responses at different scales that fit the needs of ecosystems and their services that are vital to human well-being. This methodology is now replicated at the level of the Mantaro river basin, improving with other initiatives that lead to the model of a resilient basin.

Keywords: climate-smart territories, climate change, ecosystem services, natural measures, Climate Smart Territories (CST) approach

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Authors: Natasha Yasmin Felles, Gerard Riley

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Background and Aims: Relationship breakdown is typical when one partner lives with an acquired brain injury caused by issues like a stroke. Research has found that the perception of relationship satisfaction decreases following such an injury among non-injured partners. Non-injured partners also are found to experience caregiver stress/burden as they immediately have to take the role of a caregiver along with being a partner of the injured. Research has also found that the perception of a continuous relationship, i.e. the perception of the relationship to be essentially the same as it was before the injury, also changes among those caregiving partners. However, there is a lack of available intervention strategies that can help those partners with both individual and relationship difficulties. The aim of this case study was to conduct a pilot test of an intervention aimed to explore whether it is possible to support a partner to experience greater continuity within the relationship poststroke, and what benefits such a change might have. Method: A couple, where one partner experienced an acquired brain injury poststroke were provided with Integrated Behavioural Couples Therapy for 3-months. The intervention addressed goals identified as necessary by the couple and by the formulation of their individual and relationship difficulties, alongside the goal of promoting relationship continuity. Before and after measures were taken using a battery of six questionnaires to evaluate changes in perceptions of continuity, stress, and other aspects of the relationship. Results: Both quantitative and qualitative data showed that relationship continuity was improved after the therapy, as were the measures of stress and other aspects of the relationship. The stress felt by the person with the acquired brain injury also showed some evidence of improvement. Conclusion: The study found that perceptions of relationship continuity can be improved by therapy and that improving these might have a beneficial impact on the stress felt by the carer, their satisfaction with the relationship and overall levels of conflict and closeness within the relationship. The study suggested the value of further research on enhancing perceptions of continuity in the relationship after an acquired brain injury. Currently, the findings of the study have been used to develop a pilot feasibility study to collect substantive evidence on the impact of the intervention on the couples and assess its feasibility and acceptability, which will help in further developing a specific generalized relationship continuity intervention, that will be beneficial in preventing relationship breakdown in the future.

Keywords: acquired brain injury, couples therapy, relationship continuity, stroke

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Authors: Ahmed Sami Hammami, Mohamed Jellazi

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Background: The aim of the study is to evaluate the magnitude of different psychological outcomes among Tunisian health care professionals (HCP) during the COVID-19 pandemic and to identify the associated factors. Methods: HCP completed a cross-sectional questionnaire from April 4th to April, 28th 2020. The survey collected demographic information, factors that may interfere with the psychological outcomes, behavior changes and mental health measurements. The latter was assessed through 3 scales; the 7-item questions Insomnia Severity Index, the 2-item Patient Health Questionnaire and the 2-item Generalized Anxiety Disorder. Multivariable logistic regression was conducted to identify factors associated with psychological outcomes. Results: A total of 503 HCP successfully completed the survey; among those, n=493 consented to enroll in the study, 411 [83.4%] were physicians, 323 [64.2%] were women and 271 [55%] had a second-line working position. A significant proportion of HCP had anxiety 35.7%, depression 35.1% and insomnia 23.7%. Females, those with psychiatric history and those using public transport exhibited the highest proportions for overall symptoms compared to other groups e.g., depression among females vs. males: 44,9% vs. 18,2%, P=0.00. Those with a previous medical history and nurses, had more anxiety and insomnia compared to other groups e.g. anxiety among nurses vs. interns/residents vs. attending 45,1% vs 36,1% vs 27,5%; p=0.04. Multivariable logistic regression showed that female gender was a risk factor for all psychological outcomes e.g. female sex increased the odds of anxiety by 2.86; 95% confidence interval [CI], 1, 78-4, 60; P=0.00, whereas having a psychiatric history was a risk factor for both anxiety and insomnia. (e.g. for insomnia OR=2,86; 95% [CI], 1,78-4,60; P=0.00), Having protective equipment was associated with lower risk for depression (OR=0,41; 95% CI, 0,27-0,62; P=0.00) and anxiety. Physical activity was also protective against depression and anxiety (OR=0,41, 95% CI, 0,25-0,67, P=0.00). Conclusion: Psychological symptoms are usually undervalued among HCP, though the COVID-19 pandemic played a major role in exacerbating this burden. Prompt psychological support should be endorsed and simple measures such as physical activity and ensuring the necessary protection are paramount to improve mental health outcomes and the quality of care provided to patients.

Keywords: COVID-19 pandemic, health care professionals, mental health, protective factors, psychological symptoms, risk factors

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Authors: Ankit Kumar Yadav, Nagendra R. Velaga

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Driving under the influence of alcohol impairs the driving performance and increases the crash risks worldwide. The present study investigated the effect of different Blood Alcohol Concentrations (BAC) on the accelerating and braking behaviour of drivers with the help of driving simulator experiments. Eighty-two licensed Indian drivers drove on the rural road environment designed in the driving simulator at BAC levels of 0.00%, 0.03%, 0.05%, and 0.08% respectively. Driving performance was analysed with the help of vehicle control performance indicators such as mean acceleration and mean brake pedal force of the participants. Preliminary analysis reported an increase in mean acceleration and mean brake pedal force with increasing BAC levels. Generalized linear mixed models were developed to quantify the effect of different alcohol levels and explanatory variables such as driver’s age, gender and other driver characteristic variables on the driving performance indicators. Alcohol use was reported as a significant factor affecting the accelerating and braking performance of the drivers. The acceleration model results indicated that mean acceleration of the drivers increased by 0.013 m/s², 0.026 m/s² and 0.027 m/s² for the BAC levels of 0.03%, 0.05% and 0.08% respectively. Results of the brake pedal force model reported that mean brake pedal force of the drivers increased by 1.09 N, 1.32 N and 1.44 N for the BAC levels of 0.03%, 0.05% and 0.08% respectively. Age was a significant factor in both the models where one year increase in drivers’ age resulted in 0.2% reduction in mean acceleration and 19% reduction in mean brake pedal force of the drivers. It shows that driving experience could compensate for the negative effects of alcohol to some extent while driving. Female drivers were found to accelerate slower and brake harder as compared to the male drivers which confirmed that female drivers are more conscious about their safety while driving. It was observed that drivers who were regular exercisers had better control on their accelerator pedal as compared to the non-regular exercisers during drunken driving. The findings of the present study revealed that drivers tend to be more aggressive and impulsive under the influence of alcohol which deteriorates their driving performance. Drunk driving state can be differentiated from sober driving state by observing the accelerating and braking behaviour of the drivers. The conclusions may provide reference in making countermeasures against drinking and driving and contribute to traffic safety.

Keywords: alcohol, acceleration, braking behaviour, driving simulator

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Authors: Delaram Ghodsi, Nasrin Omidvar, Hassan Eini-Zinab, Arash Rashidian, Hossein Raghfar

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Food supplementary programs are policy approaches that aim to reduce financial barriers to healthy diets and tackle food insecurity. This study aimed to evaluate the effect of the supportive section of Multidisciplinary Supplementary Program for Improvement of Nutritional Status of Children (MuPINSC) on households’ food security status and nutritional status of mothers. MuPINSC is a national integrative program in Iran that distributes supplementary food basket to malnourished or growth retarded children living in low-income families in addition to providing health services, including sanitation, growth monitoring, and empowerment of families. This longitudinal study is part of a comprehensive evaluation of the program. The study participants included 359 mothers of children aged 6 to 72 month under coverage of the supportive section of the program in two provinces of Iran (Semnan and Qazvin). Demographic and economic characteristics of families were assessed by a questionnaire. Data on food security of family was collected by locally adapted Household Food Insecurity Access Scale (HFIAS) at the baseline of the study and six month thereafter. Weight and height of mothers were measured at the baseline and end of the study and mother’s BMI was calculated. Data were analysed, using paired t-test, GEE (Generalized Estimating Equation), and Chi-square tests. Based on the findings, at the baseline, only 4.7% of families were food-secure, while 13.1%, 38.7% and, 43.5% were categorized as mild, moderate and severe food insecure. After six months follow up, the distribution of different levels of food security changed significantly (P<0.001) to 7.9%, 11.6%, 42.6%, and 38%, respectively. At the end of the study, the chance of food insecurity was significantly 20% lower than the beginning (OR=0.796; 0.653-0.971). No significant difference was observed in maternal BMI based on food security (P>0.05). The findings show that the food supplementary program for children improved household food security status in the studied households. Further research is needed to assess other factors that affect the effectiveness of this large scale program on nutritional status and household’s food security.

Keywords: food security, food supplementary program, household, malnourished children

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Authors: Moses Pinto, Ana Paula Monte

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The present research analyses the interactions between various categories of corporate social responsibility (CSR) that mediate the relationship between CSR and financial performance in Multinational Enterprises (MNE) in light of the present socio-political factors prevalent in the countries under observation. In the research it has been hypothesized that the absence of consensus in the empirical literature on the CSR–financial performance relationship may be explained by the existence of synergies (Complementarities) between the different CSR components. Upon investigation about whether such relationships exist, a final unbalanced panel sample of 1000 observations taken from 100 Multinational Enterprises per year functioning in the Schengen countries and one south east Asian country namely: India, over the span of 10 years i.e. from the year 2008 to 2018 has been analyzed. The empirical analysis used in the research methodology employs dynamic Panel Data in time series specifically, the system Generalized Method of Moments (GMM) which had been used to detect the varying degrees of relationships between the CSR and financial performance parameters in the background of the socio-political factors prevailing in the countries at the time and also taking into account the bilateral treaty obligations between the countries under observation. The econometric model has employed the financial ratio namely the Return on Assets (ROA) as an indicator of financial performance in order to gauge the internal performance and valuation of a firm as opposed to the Tobin’s Q that provides for the external evaluation of a firm’s financial performance which may not always be accurate. The various CSR dimensions have demonstrated significant correlations to the ‘ROA’ which include some negatively associated correlations and one positively associated correlation that is highly significant throughout the analysis of the observations, namely the correlation between the ‘ROA’ and the CSR dimension: ‘Environment’. The results provide a deeper insight in the synergistic CSR activities that managers could adapt into their Firm’s CSR strategy in order to enhance the ‘ROA’ and also to understand which interactions between the CSR dimensions can be adapted together due to their positively correlated association with each other and the ROA. The future lines of research would be inclined to investigate the effects of socio-political factors on the ROA of the MNEs through better designed econometric models.

Keywords: CSR, financial performance, complementarity, sociopolitical factors

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Authors: Abdulwahhab Khedr, Tamer Shehata, Hanaa El-Ghamry

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Venlafaxine HCl is a novel antidepressant drug used in the treatment of major depressive disorder, generalized anxiety disorder, social anxiety disorder and panic disorder. Conventional therapeutic regimens with venlafaxine HCl immediate-release dosage forms require frequent dosing due to short elimination half-life of the drug and reduced bioavailability. Hence, this study was carried out to develop sustained-release dosage forms of venlafaxine HCl to reduce its dosing frequency, to improve patient compliance and to reduce side effects of the drug. The polymers used were hydroxypropylmethyl cellulose, xanthan gum, sodium alginate, sodium carboxymethyl cellulose, Carbopol 940 and ethyl cellulose. The physical properties of the prepared tablets including tablet thickness, diameter, weight uniformity, content uniformity, hardness and friability were evaluated. Also, the in-vitro release of venlafaxine HCl from different matrix tablets was studied. Based on physical characters and in-vitro release profiles, certain formulae showing promising sustained-release profiles were subjected to film coating with 15% w/v EC in dichloromethane/ethanol mixture (1:1 ratio) using 1% w/v HPMC as pore former and 30% w/w dibutyl phthalate as plasticizer. The optimized formulations were investigated for drug-excipient compatibility using FTIR and DSC studies. Physical evaluation of the prepared tablets fulfilled the pharmacopoeial requirements for tablet friability test, where the weight loss of the prepared formulae did not exceed 1% of the weight of the tested tablets. Moderate release was obtained from tablets containing HPMC. FTIR and DSC studies for such formulae revealed the absence of any type of chemical interaction between venlafaxine HCl and the used polymers or excipients. Forced swimming test in rats was used to evaluate the antidepressant activity of the selected matrix tablets of venlafaxine HCl. Results showed that formulations significantly decreased the duration of animals’ immobility during the 24 hr-period of the test compared to non-treated group.

Keywords: antidepressant, sustained-release, matrix tablet, venlafaxine hydrochloride

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Authors: Damianos Tzoupis

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In the context of the canon debate, assumptions regarding the place, value, and impact of classical texts have come under increased scrutiny. Factors like the distance of time, the depreciation of tradition, or the increased cultural omnivorousness and eclecticism have allegedly played a part in destabilizing classics’ authority. However, despite all these developments, classics’ position and influence is strong both in contemporary institutions and among readers’ preferences. Within this background of conflicted narratives, the study maps the varied discourses, value grammars, and justifications that lay cultural consumers employ to discuss those texts which have come to be the most consecrated and valuable cultural objects. The study centers on reviews posted on Goodreads. These online reviews offer unique access to unsolicited reception data produced by lay readers themselves, thus providing a clearer picture of lay cultural consumption and lay theories about classics. Moreover, the approach taken relies on the micro-practices of evaluation: the study investigates the evaluation of a specific cultural object, namely Plato’s allegory of the Cave, and treats it as an exemplary case to identify interpretive repertoires and valuation grammars about classical texts in general. The analysis uncovers a wide range of discourses used to construct the concept of the “classical text”. At first sight, lay reviewers seem to adopt interpretive repertoires that highlight qualities such as universality, timelessness, canonicity, cultural impact, and difficulty. These repertoires seem in principle to follow generalized and institutionalized discourses about classical texts, as these are established and circulated by institutions and cultural brokers like schools, academics, critics, etc. However, the study also uncovers important variations of these discourses. Lay readers tend to (re)negotiate the meanings/connotations of the above qualities and also structure their discourses by “modalities” such as necessity or surprise. These variations in interpretive repertoires are important in cultural sociology’s attempt to better grasp the principles informing the grammars of valuation that lay cultural consumers employ and to understand the kinds of impact that consecrated cultural objects have on people’s lives.

Keywords: classics, interpretive repertoires around classicalness, institutionalized discourses, lay readers, online reviews/criticism

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Authors: Sara Bahariderakhshan, Morteza Ahmadifar

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Leakage is one of the most important problems that water distribution networks face which first reason is high-pressure existence. There are many approaches to control this excess pressure, which using pressure reducing valves (PRVs) or reducing pipe diameter are ones. In the other hand, Pumps are using electricity or fossil fuels to supply needed pressure in distribution networks but excess pressure are made in some branches due to topology problems and water networks’ variables therefore using pressure valves will be inevitable. Although using PRVs is inevitable but it leads to waste electricity or fuels used by pumps because PRVs just waste excess hydraulic pressure to lower it. Pumps working in reverse or Pumps as Turbine (called PaT in this article) are easily available and also effective sources of reducing the equipment cost in small hydropower plants. Urban areas of developing countries are facing increasing in area and maybe water scarcity in near future. These cities need wider water networks which make it hard to predict, control and have a better operation in the urban water cycle. Using more energy and, therefore, more pollution, slower repairing services, more user dissatisfaction and more leakage are these networks’ serious problems. Therefore, more effective systems are needed to monitor and act in these complicated networks than what is used now. In this article a new approach is proposed and evaluated: Using PAT to produce enough energy for remote valves and sensors in the water network. These sensors can be used to determine the discharge, pressure, water quality and other important network characteristics. With the help of remote valves pipeline discharge can be controlled so Instead of wasting excess hydraulic pressure which may be destructive in some cases, obtaining extra pressure from pipeline and producing clean electricity used by remote instruments is this articles’ goal. Furthermore due to increasing the area of the network there is unwanted high pressure in some critical points which is not destructive but lowering the pressure results to longer lifetime for pipeline networks without users’ dissatisfaction. This strategy proposed in this article, leads to use PaT widely for pressure containment and producing energy needed for remote valves and sensors like what happens in supervisory control and data acquisition (SCADA) systems which make it easy for us to monitor, receive data from urban water cycle and make any needed changes in discharge and pressure of pipelines easily and remotely. This is a clean project of energy production without significant environmental impacts and can be used in urban drinking water networks, without any problem for consumers which leads to a stable and dynamic network which lowers leakage and pollution.

Keywords: new energies, pump as turbine, drinking water, distribution network, remote control equipments

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Authors: Morteza Ahmadifar, Sarah Bahari Derakhshan

Abstract:

Leakage is one of the most important problems that water distribution networks face which first reason is high-pressure existence. There are many approaches to control this excess pressure, which using pressure reducing valves (PRVs) or reducing pipe diameter are ones. On the other hand, Pumps are using electricity or fossil fuels to supply needed pressure in distribution networks but excess pressure are made in some branches due to topology problems and water networks’ variables, therefore using pressure valves will be inevitable. Although using PRVs is inevitable but it leads to waste electricity or fuels used by pumps because PRVs just waste excess hydraulic pressure to lower it. Pumps working in reverse or Pumps as Turbine (called PAT in this article) are easily available and also effective sources of reducing the equipment cost in small hydropower plants. Urban areas of developing countries are facing increasing in area and maybe water scarcity in near future. These cities need wider water networks which make it hard to predict, control and have a better operation in the urban water cycle. Using more energy and therefore more pollution, slower repairing services, more user dissatisfaction and more leakage are these networks’ serious problems. Therefore, more effective systems are needed to monitor and act in these complicated networks than what is used now. In this article a new approach is proposed and evaluated: Using PAT to produce enough energy for remote valves and sensors in the water network. These sensors can be used to determine the discharge, pressure, water quality and other important network characteristics. With the help of remote valves pipeline discharge can be controlled so Instead of wasting excess hydraulic pressure which may be destructive in some cases, obtaining extra pressure from pipeline and producing clean electricity used by remote instruments is this articles’ goal. Furthermore, due to increasing the area of network there is unwanted high pressure in some critical points which is not destructive but lowering the pressure results to longer lifetime for pipeline networks without users’ dissatisfaction. This strategy proposed in this article, leads to use PAT widely for pressure containment and producing energy needed for remote valves and sensors like what happens in supervisory control and data acquisition (SCADA) systems which make it easy for us to monitor, receive data from urban water cycle and make any needed changes in discharge and pressure of pipelines easily and remotely. This is a clean project of energy production without significant environmental impacts and can be used in urban drinking water networks, without any problem for consumers which leads to a stable and dynamic network which lowers leakage and pollution.

Keywords: clean energies, pump as turbine, remote control, urban water distribution network

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Authors: Abbas Kamalibandpey, Alain Beland, Joseph Mukendi Kabuya

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Since a rock mass is a discontinuum medium, its behaviour is governed by discontinuities such as faults, joint sets, lithologic contact, and bedding planes. Thus, rock slope stability analysis in jointed rock masses is largely dependent upon discontinuities constitutive equations. This paper studies the difference between the Mohr-Coulomb (MC) and the Barton-Bandis (BB) joint constitutive numerical models for lithological contacts and joint sets. For the rock in these models, generalized Hoek-Brown criteria have been considered. The joint roughness coefficient (JRC) and the joint wall compressive strength (JCS) are vital parameters in the BB model. The numerical models are applied to the rock slope stability analysis in the Mont-Wright (MW) mine. The Mont-Wright mine is owned and operated by ArcelorMittal Mining Canada (AMMC), one of the largest iron-ore open pit operations in Canada. In this regard, one of the high walls of the mine has been selected to undergo slope stability analysis with RS2D software, finite element method. Three piezometers have been installed in this zone to record pore water pressure and it is monitored by radar. In this zone, the AMP-IF and QRMS-IF contacts and very persistent and altered joint sets in IF control the rock slope behaviour. The height of the slope is more than 250 m and consists of different lithologies such as AMP, IF, GN, QRMS, and QR. To apply the B-B model, the joint sets and geological contacts have been scanned by Maptek, and their JRC has been calculated by different methods. The numerical studies reveal that the JRC of geological contacts, AMP-IF and QRMS-IF, and joint sets in IF had a significant influence on the safety factor. After evaluating the results of rock slope stability analysis and the radar data, the B-B constitutive equation for discontinuities has shown acceptable results to the real condition in the mine. It should be noted that the difference in safety factors in MC and BB joint constitutive models in some cases is more than 30%.

Keywords: barton-Bandis criterion, Hoek-brown and Mohr-Coulomb criteria, open pit, slope stability

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Authors: Derradji A., Ben El Mamoun M., Zakaria E., Charadi I. Anrur

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The issue of dilapidated buildings represents a significant opportunity for constructive and beneficial interventions in Morocco. Faced with challenges associated with aging constructions and rapid urbanization, the country is committed to developing innovative strategies aimed at revitalizing urban areas and enhancing the sustainability of infrastructure, thereby ensuring citizens' safety. Through targeted investments in the renovation and modernization of existing buildings, Morocco aims to stimulate job creation, boost the local economy, and improve the quality of life for residents. Additionally, the integration of sustainable construction standards and the strengthening of regulations will promote resilient and environmentally friendly urban development. In this proactive perspective, LABOTEST has been commissioned by the National Agency for Urban Renewal (ANRUR) to conduct an in-depth study. This study focuses on the technical expertise of 1800 buildings identified as dilapidated in the prefectures of Rabat and Skhirat-Témara following an initial clearance operation. The primary objective of this initiative is to conduct a comprehensive diagnosis of these buildings and define the necessary interventions to eliminate potential risks while ensuring appropriate treatment. The article presents the adopted intervention methodology, taking into account the social dimensions involved, as well as the results of the technical expertise. These results include the classification of buildings according to their degree of urgency and recommendations for appropriate conservatory measures. Additionally, different pathologies are identified and accompanied by specific treatment proposals for each type of building. Since this study, the adopted approach has been generalized to the entire territory of Morocco. LABOTEST has been solicited by other cities such as Casablanca, Chefchaouen, Ouazzane, Azilal, Bejaad, and Demnate. This extension of the initiative demonstrates Morocco's commitment to addressing urban challenges in a proactive and inclusive manner. These efforts also illustrate the endeavors undertaken to transform urban challenges into opportunities for sustainable development and socio-economic progress for the entire population.

Keywords: building, dilapidated, rehabilitation, Morocco

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Authors: Maatouk Khoukhi

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Nowadays the reduction of the energy consumed by buildings to achieve mainly the thermal comfort for the occupants represent the main concern for architects and building designers. The common and traditional solution to achieve this target is the design of a highly insulated envelope and reduce the opening and the transparent elements such windows. However, this will lead to the artificial lighting system to consume more energy to compensate the lack of natural lighting coming through the glazed parts of the building envelope. Therefore, a good balance between sufficient daylight and control thermal heat through the building envelope should be considered for energy saving purpose. To achieve a better indoor environment the windows size and spacing including the interior finishing and the location of the partition must be assessed accurately. Daylighting is the controlled admission of natural light into space through windows and transparent elements of the building envelope which helps create a visually stimulating and productive environment for building occupants. The main concern is not to provide enough daylight to an occupied space, but how to achieve this without any undesirable side effect. Indeed, the glare is a major problem in glazed façade buildings, and this could be reduced by using tinted windows. The main target of this research is to investigate the daylight adequacy of functional needs in old Omani Forts and how they have been designed and built to avoid glare and overheating with the appropriate window-to-floor ratio. Because more windows do not automatically result in more daylighting but that is natural light has been controlled and distributed properly throughout the space. Spaces from different Omani and Portuguese Forts under the same climate conditions are considered in order to compare the daylight illuminance levels and examine the similarities and differences in visual attributes between them. The result of this study indicates that lighting preference is not universal and people from different geographical locations are adapted to certain illuminance levels. Therefore, the standards could not be generalized for the entire world. This would be useful to practitioners who are designing to effectively address the diversity of user’s lighting levels preferences in our globally connected society.

Keywords: day lighting, energy, forts, thermal comfort

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Authors: M. Paraipan, V. M. Javadova, S. I. Tyutyunnikov

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The concept of energy amplifier or accelerator driven system (ADS) involves the use of a particle accelerator coupled with a nuclear reactor. The accelerated particle beam generates a supplementary source of neutrons, which allows the subcritical functioning of the reactor, and consequently a safe exploitation. The harder neutron spectrum realized ensures a better incineration of the actinides. The almost generalized opinion is that the optimal beam for ADS is represented by protons with energy around 1 GeV (gigaelectronvolt). In the present work, a systematic analysis of the energy gain for proton beams with energy from 0.5 to 3 GeV and ion beams from deuteron to neon with energies between 0.25 and 2 AGeV is performed. The target is an assembly of metallic U-Pu-Zr fuel rods in a bath of lead-bismuth eutectic coolant. The rods length is 150 cm. A beryllium converter with length 110 cm is used in order to maximize the energy released in the target. The case of a linear accelerator is considered, with a beam intensity of 1.25‧10¹⁶ p/s, and a total accelerator efficiency of 0.18 for proton beam. These values are planned to be achieved in the European Spallation Source project. The energy gain G is calculated as the ratio between the energy released in the target to the energy spent to accelerate the beam. The energy released is obtained through simulation with the code Geant4. The energy spent is calculating by scaling from the data about the accelerator efficiency for the reference particle (proton). The analysis concerns the G values, the net power produce, the accelerator length, and the period between refueling. The optimal energy for proton is 1.5 GeV. At this energy, G reaches a plateau around a value of 8 and a net power production of 120 MW (megawatt). Starting with alpha, ion beams have a higher G than 1.5 GeV protons. A beam of 0.25 AGeV(gigaelectronvolt per nucleon) ⁷Li realizes the same net power production as 1.5 GeV protons, has a G of 15, and needs an accelerator length 2.6 times lower than for protons, representing the best solution for ADS. Beams of ¹⁶O or ²⁰Ne with energy 0.75 AGeV, accelerated in an accelerator with the same length as 1.5 GeV protons produce approximately 900 MW net power, with a gain of 23-25. The study of the evolution of the isotopes composition during irradiation shows that the increase in power production diminishes the period between refueling. For a net power produced of 120 MW, the target can be irradiated approximately 5000 days without refueling, but only 600 days when the net power reaches 1 GW (gigawatt).

Keywords: accelerator driven system, ion beam, electrical power, energy gain

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Authors: Eyup Dogan

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The number of research articles analyzing the integration properties of energy variables has rapidly increased in the energy literature for about a decade. The stochastic behaviors of energy variables are worth knowing due to several reasons. For instance, national policies to conserve or promote energy consumption, which should be taken as shocks to energy consumption, will have transitory effects in energy consumption if energy consumption is found to be stationary in one country. Furthermore, it is also important to know the order of integration to employ an appropriate econometric model. Despite being an important subject for applied energy (economics) and having a huge volume of studies, several known limitations still exist with the existing literature. For example, many of the studies use aggregate energy consumption and national level data. In addition, a huge part of the literature is either multi-country studies or solely focusing on the U.S. This is the first study in the literature that considers a form of energy consumption by sectors at sub-national level. This research study aims at investigating unit root properties of electricity consumption for 12 regions of Turkey by four sectors in addition to total electricity consumption for the purpose of filling the mentioned limits in the literature. In this regard, we analyze stationarity properties of 60 cases . Because the use of multiple unit root tests make the results robust and consistent, we apply Dickey-Fuller unit root test based on Generalized Least Squares regression (DFGLS), Phillips-Perron unit root test (PP) and Zivot-Andrews unit root test with one endogenous structural break (ZA). The main finding of this study is that electricity consumption is trend stationary in 7 cases according to DFGLS and PP, whereas it is stationary process in 12 cases when we take into account the structural change by applying ZA. Thus, shocks to electricity consumption have transitory effects in those cases; namely, agriculture in region 1, region 4 and region 7, industrial in region 5, region 8, region 9, region 10 and region 11, business in region 4, region 7 and region 9, total electricity consumption in region 11. Regarding policy implications, policies to decrease or stimulate the use of electricity have a long-run impact on electricity consumption in 80% of cases in Turkey given that 48 cases are non-stationary process. On the other hand, the past behavior of electricity consumption can be used to predict the future behavior of that in 12 cases only.

Keywords: unit root, electricity consumption, sectoral data, subnational data

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Authors: Teris Cheung, Joyce Yuen Ting Lam, Kwan Hin Fong, Yuen Shan Ho, Tim Man Ho Li, Andy Choi-Yeung Tse, Cheng-Ta Li, Calvin Pak-Wing Cheng, Roland Beisteiner

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Transcranial pulse stimulation (TPS) is a non-intrusive brain stimulation technology that has been proven effective in older adults with mild neurocognitive disorders and adults with major depressive disorder. Given these robust evidences, TPS might be an adjunct treatment options in neuropsychiatric disorders, for example, autism spectrum disorder (ASD) – which is a common neurodevelopmental disorder in children. This trial aimed to investigate the effects of TPS on right temporoparietal junction, a key node for social cognition for Autism Spectrum Disorder (ASD), and to examine the association between TPS, executive functions and social functions. Design: This trial adopted a two-armed (verum TPS group vs. sham TPS group), double-blinded, randomized, sham-controlled design. Sampling: 32 subjects aged between 12 and 17, diagnosed with ASD were recruited. All subjects were computerized randomized into either verum TPS group or the sham TPS group on a 1:1 ratio. All subjects undertook functional MRI before and after the TPS interventions. Intervention: Six 30-min TPS sessions were administered to subjects in 2 weeks’ time on alternate days assessing neural connectivity changes. Baseline measurements and post-TPS evaluation of the ASD symptoms, executive functions, and social functions were conducted. Participants were followed up at 2-weeks, at 1-month and 3-month, assessing the short-and long-term sustainability of the TPS intervention. Data analysis: Generalized Estimating Equations with repeated measures were used to analyze the group and time difference. Missing data were managed by multiple imputations. The level of significance was set at p < 0.05. To our best knowledge, this is the first study evaluating the efficacy and safety of TPS among adolescents with ASD in Hong Kong and nationwide. Results emerging from this study will develop insight on whether TPS can be used as an adjunct treatment on ASD in neuroscience and clinical psychiatry. Clinical Trial Registration: ClinicalTrials.gov, identifier: NCT05408793.

Keywords: adolescents, autism spectrum disorder, neuromodulation, rct, transcranial pulse stimulation

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Authors: Mohaammad Ahmadpanah, Amineh Akhondi, Mohammad Haghighi, Ali Ghaleiha, Leila Jahangard, Elham Salari

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Background: Working memory includes the capability to keep and manipulate information in a short period of time. This capability is the basis of complicated judgments and has been attended to as the specific and constant character of individuals. Children with attention deficit and hyperactivity are among the people suffering from deficiency in the active memory, and this deficiency has been attributed to the problem of frontal lobe. This study utilizes a new approach with suitable tasks and methods for training active memory and assessment of the effects of the trainings. Participants: The children participating in this study were of 7-15 year age, who were diagnosed by the psychiatrist and psychologist as hyperactive and attention deficit based on DSM-IV criteria. The intervention group was consisted of 8 boys and 6 girls with the average age of 11 years and standard deviation of 2, and the control group was consisted of 2 girls and 5 boys with an average age of 11.4 and standard deviation of 3. Three children in the test group and two in the control group were under medicinal therapy. Results: Working memory training meaningfully improved the performance in not-trained areas as visual-spatial working memory as well as the performance in Raven progressive tests which are a perfect example of non-verbal, complicated reasoning tasks. In addition, motional activities – measured based on the number of head movements during computerized measuring program – was meaningfully reduced in the medication group. The results of the second test showed that training similar exercise to teenagers and adults results in the improvement of cognition functions, as in hyperactive people. Discussion: The results of this study showed that the performance of working memory is improved through training, and these trainings are extended and generalized in other areas of cognition functions not receiving any training. Trainings resulted in the improvement of performance in the tasks related to prefrontal. They had also a positive and meaningful impact on the moving activities of hyperactive children.

Keywords: attention deficit hyperactivity disorder, working memory, non-medical treatment, children

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Authors: Fikru Fentaw Abera

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Climate changes alter regional hydrologic conditions and results in a variety of impacts on water resource systems. Such hydrologic changes will affect almost every aspect of human well-being. The goal of this paper is to assess the impact of climate change on the hydrology of Upper Guder catchment located in northwest of Ethiopia. The GCM derived scenarios (HadCM3 A2a & B2a SRES emission scenarios) experiments were used for the climate projection. The statistical downscaling model (SDSM) was used to generate future possible local meteorological variables in the study area. The down-scaled data were then used as input to the soil and water assessment tool (SWAT) model to simulate the corresponding future stream flow regime in Upper Guder catchment of the Abay River Basin. A semi distributed hydrological model, SWAT was developed and Generalized Likelihood Uncertainty Estimation (GLUE) was utilized for uncertainty analysis. GLUE is linked with SWAT in the Calibration and Uncertainty Program known as SWAT-CUP. Three benchmark periods simulated for this study were 2020s, 2050s and 2080s. The time series generated by GCM of HadCM3 A2a and B2a and Statistical Downscaling Model (SDSM) indicate a significant increasing trend in maximum and minimum temperature values and a slight increasing trend in precipitation for both A2a and B2a emission scenarios in both Gedo and Tikur Inch stations for all three bench mark periods. The hydrologic impact analysis made with the downscaled temperature and precipitation time series as input to the hydrological model SWAT suggested for both A2a and B2a emission scenarios. The model output shows that there may be an annual increase in flow volume up to 35% for both emission scenarios in three benchmark periods in the future. All seasons show an increase in flow volume for both A2a and B2a emission scenarios for all time horizons. Potential evapotranspiration in the catchment also will increase annually on average 3-15% for the 2020s and 7-25% for the 2050s and 2080s for both A2a and B2a emissions scenarios.

Keywords: climate change, Guder sub-basin, GCM, SDSM, SWAT, SWAT-CUP, GLUE

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Authors: Zaki Abiza, Miguel Chavez, David M. Holman, Ruddy Brionnaud

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In this paper, the prediction of the aerodynamic behavior of the flow around a Finned Projectile will be validated using a Computational Fluid Dynamics (CFD) solution, XFlow, based on the Lattice-Boltzmann Method (LBM). XFlow is an innovative CFD software developed by Next Limit Dynamics. It is based on a state-of-the-art Lattice-Boltzmann Method which uses a proprietary particle-based kinetic solver and a LES turbulent model coupled with the generalized law of the wall (WMLES). The Lattice-Boltzmann method discretizes the continuous Boltzmann equation, a transport equation for the particle probability distribution function. From the Boltzmann transport equation, and by means of the Chapman-Enskog expansion, the compressible Navier-Stokes equations can be recovered. However to simulate compressible flows, this method has a Mach number limitation because of the lattice discretization. Thanks to this flexible particle-based approach the traditional meshing process is avoided, the discretization stage is strongly accelerated reducing engineering costs, and computations on complex geometries are affordable in a straightforward way. The projectile that will be used in this work is the Army-Navy Basic Finned Missile (ANF) with a caliber of 0.03 m. The analysis will consist in varying the Mach number from M=0.5 comparing the axial force coefficient, normal force slope coefficient and the pitch moment slope coefficient of the Finned Projectile obtained by XFlow with the experimental data. The slope coefficients will be obtained using finite difference techniques in the linear range of the polar curve. The aim of such an analysis is to find out the limiting Mach number value starting from which the effects of high fluid compressibility (related to transonic flow regime) lead the XFlow simulations to differ from the experimental results. This will allow identifying the critical Mach number which limits the validity of the isothermal formulation of XFlow and beyond which a fully compressible solver implementing a coupled momentum-energy equations would be required.

Keywords: CFD, computational fluid dynamics, drag, finned projectile, lattice-boltzmann method, LBM, lift, mach, pitch

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Authors: Aniko Babits, Ahmad Daoud

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Introduction: The beach chair position (BCP) is a good approach to almost all types of shoulder procedures. However, moving an anaesthetized patient from the supine to sitting position may pose a risk of cerebral hypoperfusion and potential cerebral ischaemia as a result of significant reductions in blood pressure and cardiac output. Hypocapnia in ventilated patients and impaired blood flow to the vertebral artery due to hyperextension, rotation, or tilt of the head may have an impact too. Co-morbidities that may increase the risk of cerebral ischaemia in the BCP include diabetes with autonomic neuropathy, cerebrovascular disease, cardiac disease, severe hypertension, generalized vascular disease, history of fainting, and febrile conditions. Beach chair surgery requires a careful anaesthetic and surgical management to optimize patient safety and minimize the risk of adverse outcomes. Methods: We describe the necessary steps for optimal patient positioning and the aims of intraoperative management, including anaesthetic techniques to ensure patient safety in the BCP. Results: Regardless of the anaesthetic technique, adequate patient positioning is paramount in the BCP. The key steps to BCP are aimed at optimizing surgical success and minimizing the risk of severe neurovascular complications. The primary aim of anaesthetic management is to maintain cardiac output and mean arterial pressure (MAP) to protect cerebral perfusion. Blood pressure management includes treating a fall in MAP of more than 25% from baseline or a MAP less than 70 mmHg. This can be achieved by using intravenous fluids or vasopressors. A number of anaesthetic techniques could also improve cerebral oxygenation, including avoidance of intermittent positive pressure ventilation (IPPV) with general anaesthesia (GA), using regional anaesthesia, maintaining normocapnia and normothermia, and the application of compression stockings. Conclusions: In summary, BCP is a reliable and effective position to perform shoulder procedures. Simple steps to patient positioning and careful anaesthetic management could maximize patient safety and avoid unwanted adverse outcomes in patients undergoing surgery in BCP.

Keywords: beach chair position, cerebral oxygenation, cerebral perfusion, sitting position

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Authors: Antoinette Maarawi, Zoe Anxionnaz-Minvielle, Pierre Coste, Nathalie Di Miceli Raimondi, Michel Cabassud

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Milli-structured heat exchanger/reactors have been recently widely used, especially in the chemical industry, due to their enhanced performances in heat and mass transfer compared to conventional apparatuses. In our work, the ‘DeanHex’ heat exchanger/reactor with a 2D-meandering channel is investigated both experimentally and numerically. The square cross-sectioned channel has a hydraulic diameter of 2mm. The aim of our study is to model local physico-chemical phenomena (heat and mass transfer, axial dispersion, etc.) for a liquid-liquid two-phase flow in our lab-scale meandering channel, which represents the central part of the heat exchanger/reactor design. The numerical approach of the reactor is based on a 1D model for the flow channel encapsulated in a 3D model for the surrounding solid, using COMSOL Multiphysics V5.5. The use of the 1D approach to model the milli-channel reduces significantly the calculation time compared to 3D approaches, which are generally focused on local effects. Our 1D/3D approach intends to bridge the gap between the simulation at a small scale and the simulation at the reactor scale at a reasonable CPU cost. The heat transfer process between the 1D milli-channel and its 3D surrounding is modeled. The feasibility of this 1D/3D coupling was verified by comparing simulation results to experimental ones originated from two previous works. Temperature profiles along the channel axis obtained by simulation fit the experimental profiles for both cases. The next step is to integrate the liquid-liquid mass transfer model and to validate it with our experimental results. The hydrodynamics of the liquid-liquid two-phase system is modeled using the ‘mixture model approach’. The mass transfer behavior is represented by an overall volumetric mass transfer coefficient ‘kLa’ correlation obtained from our experimental results in the millimetric size meandering channel. The present work is a first step towards the scale-up of our ‘DeanHex’ expecting future industrialization of such equipment. Therefore, a generalized scaled-up model of the reactor comprising all the transfer processes will be built in order to predict the performance of the reactor in terms of conversion rate and energy efficiency at an industrial scale.

Keywords: liquid-liquid mass transfer, milli-structured reactor, 1D/3D model, process intensification

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Authors: Qiao-Yu Warren Cai

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Due to the rise of big data, building corpora and using them to analyze ChineseL2 learners’ language output has become a trend. Various empirical research has been conducted using Chinese corpora built by different academic institutes. However, most of the research analyzed the data in the Chinese corpora usingcorpus-based qualitative content analysis with descriptive statistics. Descriptive statistics can be used to make summations about the subjects or samples that research has actually measured to describe the numerical data, but the collected data cannot be generalized to the population. Comte, a Frenchpositivist, has argued since the 19th century that human beings’ knowledge, whether the discipline is humanistic and social science or natural science, should be verified in a scientific way to construct a universal theory to explain the truth and human beings behaviors. Inferential statistics, able to make judgments of the probability of a difference observed between groups being dependable or caused by chance (Free Geography Notes, 2015)and to infer from the subjects or examples what the population might think or behave, is just the right method to support Comte’s argument in the field of TCSOL. Also, inferential statistics is a core of quantitative research, but little research has been conducted by combing corpora with inferential statistics. Little research analyzes the differences in Chinese L2 learners’ language corpus output errors by using theOne-way ANOVA so that the findings of previous research are limited to inferring the population's Chinese errors according to the given samples’ Chinese corpora. To fill this knowledge gap in the professional development of Taiwanese TCSOL, the present study aims to utilize the One-way ANOVA to analyze corpus output errors of Chinese L2 learners from America, Myanmar, and Singapore. The results show that no significant difference exists in ‘shì (是) sentence’ and word order errors, but compared with Americans and Singaporeans, it is significantly easier for Myanmar to have ‘sentence blends.’ Based on the above results, the present study provides an instructional approach and contributes to further exploration of how Chinese L2 learners can have (and use) learning strategies to lower errors.

Keywords: Chinese corpus, error analysis, one-way analysis of variance, Chinese L2 learners, Americans, myanmar, Singaporeans

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Authors: Jui-Hsueh Hu

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This study investigated various models of refusal speech acts among three target groups: French learners of Mandarin Chinese (FM), Taiwanese native Mandarin speakers (TM), and native French speakers (NF). The refusal responses were analyzed in terms of their options, frequencies, and sequences and the contents of their semantic formulas. This study also examined differences in refusal strategies, as determined by social status and social distance, among the three groups. The difficulties of refusal speech acts encountered by FM were then generalized. The results indicated that Mandarin instructors of NF should focus on the different reasons for the pragmatic failure of French learners and should assist these learners in mastering refusal speech acts that rely on abundant cultural information. In this study, refusal policies were mainly classified according to the research of Beebe et al. (1990). Discourse completion questionnaires were collected from TM, FM, and NF, and their responses were compared to determine how refusal policies differed among the groups. This study not only emphasized the dissimilarities of refusal strategies between native Mandarin speakers and second-language Mandarin learners but also used NF as a control group. The results of this study demonstrated that regarding overall strategies, FM were biased toward NF in terms of strategy choice, order, and content, resulting in pragmatic transfer under the influence of social factors such as 'social status' and 'social distance,' strategy choices of FM were still closer to those of NF, and the phenomenon of pragmatic transfer of FM was revealed. Regarding the refusal difficulties among the three groups, the F-test in the analysis of variance revealed statistical significance was achieved for Role Playing Items 13 and 14 (P < 0.05). A difference was observed in the average number of refusal difficulties between the participants. However, after multiple comparisons, it was found that item 13 (unrecognized heterosexual junior colleague requesting contacts) was significantly more difficult for NF than for TM and FM; item 14 (contacts requested by an unrecognized classmate of the opposite sex) was significantly more difficult to refuse for NF than for TM. This study summarized the pragmatic language errors that most FM often perform, including the misuse or absence of modal words, hedging expressions, and empty words at the end of sentences, as the reasons for pragmatic failures. The common social pragmatic failures of FM include inaccurately applying the level of directness and formality.

Keywords: French Mandarin, interlanguage refusal, pragmatic transfer, speech acts

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Authors: Vitas Valinčius, Rolandas Uscila, Viktorija Grigaitienė, Žydrūnas Kavaliauskas, Romualdas Kėželis

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Determination of integral dynamical and energy characteristics of high-temperature gas flows is a very important task of gas-dynamic for hazardous substances destruction systems. They are also always necessary for the investigation of high-temperature turbulent flow dynamics, heat and mass transfer. It is well known that distribution of dynamical and thermal characteristics of high-temperature flows and jets is strongly related to heat flux variation over an imposed area of heating. As is visible from numerous experiments and theoretical considerations, the fundamental properties of an isothermal jet are well investigated. However, the establishment of regularities in high-temperature conditions meets certain specific behavior comparing with moderate-temperature jets and flows. Their structures have not been thoroughly studied yet, especially in the cases of plasma ambient. It is well known that the distribution of local plasma jet parameters in high temperature and isothermal jets and flows may significantly differ. High temperature axisymmetric air jet generated by atmospheric pressure DC arc plasma torch was investigated employing enthalpy probe 3.8∙10-3 m of diameter. Distribution of velocities and temperatures were established in different cross-sections of the plasma jet outflowing from 42∙10-3 m diameter pipe at the average mean velocity of 700 m∙s-1, and averaged temperature of 4000 K. It has been found that gas heating fractionally influences shape and values of a dimensionless profile of velocity and temperature in the main zone of plasma jet and has a significant influence in the initial zone of the plasma jet. The width of the initial zone of the plasma jet has been found to be lesser than in the case of isothermal flow. The relation between dynamical thickness and turbulent number of Prandtl has been established along jet axis. Experimental results were generalized in dimensionless form. The presence of convective heating shows that heat transfer in a moving high-temperature jet also occurs due to heat transfer by moving particles of the jet. In this case, the intensity of convective heat transfer is proportional to the instantaneous value of the flow velocity at a given point in space. Consequently, the configuration of the temperature field in moving jets and flows essentially depends on the configuration of the velocity field.

Keywords: plasma jet, plasma torch, heat transfer, enthalpy probe, turbulent number of Prandtl

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Authors: Rakelane A. Mendes, Sandro T. M. Goncalves, Raphaella L. R. Silva

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The concepts of energy harvesting and wireless energy transfer have been widely discussed in recent times. There are some ways to create autonomous systems for collecting ambient energy, such as solar, vibratory, thermal, electromagnetic, radiofrequency (RF), among others. In the case of the RF it is possible to collect up to 100 μW / cm². To collect and/or transfer energy in RF systems, a device called rectenna is used, which is defined by the junction of an antenna and a rectifier circuit. The rectenna presented in this work is resonant at the frequencies of 1.8 GHz and 2.45 GHz. Frequencies at 1.8 GHz band are e part of the GSM / LTE band. The GSM (Global System for Mobile Communication) is a frequency band of mobile telephony, it is also called second generation mobile networks (2G), it came to standardize mobile telephony in the world and was originally developed for voice traffic. LTE (Long Term Evolution) or fourth generation (4G) has emerged to meet the demand for wireless access to services such as Internet access, online games, VoIP and video conferencing. The 2.45 GHz frequency is part of the ISM (Instrumentation, Scientific and Medical) frequency band, this band is internationally reserved for industrial, scientific and medical development with no need for licensing, and its only restrictions are related to maximum power transfer and bandwidth, which must be kept within certain limits (in Brazil the bandwidth is 2.4 - 2.4835 GHz). The rectenna presented in this work was designed to present efficiency above 50% for an input power of -15 dBm. It is known that for wireless energy capture systems the signal power is very low and varies greatly, for this reason this ultra-low input power was chosen. The Rectenna was built using the low cost FR4 (Flame Resistant) substrate, the antenna selected is a microfita antenna, consisting of a Meandered dipole, and this one was optimized using the software CST Studio. This antenna has high efficiency, high gain and high directivity. Gain is the quality of an antenna in capturing more or less efficiently the signals transmitted by another antenna and/or station. Directivity is the quality that an antenna has to better capture energy in a certain direction. The rectifier circuit used has series topology and was optimized using Keysight's ADS software. The rectifier circuit is the most complex part of the rectenna, since it includes the diode, which is a non-linear component. The chosen diode is the Schottky diode SMS 7630, this presents low barrier voltage (between 135-240 mV) and a wider band compared to other types of diodes, and these attributes make it perfect for this type of application. In the rectifier circuit are also used inductor and capacitor, these are part of the input and output filters of the rectifier circuit. The inductor has the function of decreasing the dispersion effect on the efficiency of the rectifier circuit. The capacitor has the function of eliminating the AC component of the rectifier circuit and making the signal undulating.

Keywords: dipole antenna, double-band, high efficiency, rectenna

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Authors: Ming Yi Hsu, Hui Jung Chao

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The anxiety and depression adolescents in Taiwan experience can cause suicide attempts and result in unfortunate deaths. An effective method for relieving anxiety and depression is brisk walking; a moderate and low intensity aerobic exercise, which uses large muscle groups rhythmically. The research purpose was to investigate the effects of a 12-week, school-based, brisk-walking program in decreasing anxiety and depression, and in improving self-concept among high school students living in central Taiwan. A quasi-experiment using the time series design (T1 T2 X T3 T4) was conducted. The Beck Youth Inventories 2 (BYI-II) Chinese version was given four times: the first time T1 was in the 4th week prior to intervention, T2 was in the intervention week, T3 was in the 6th week after the start of the intervention period and T4 was in the 12th week post intervention. The baseline phase of the time series constituted T1 and T2. The intervention phase constituted T2, T3, and T4. The amounts of brisk walking were recorded by self-report The Generalized Estimating Equation (GEE) was used to examine the effects of brisk walking on anxiety, depression, and self-concept. The independent t-test was used to compare mean scores on three dependent variables between brisk walking over and less than 90-minutes per week. Findings revealed that levels of anxiety and self-concept had nonsignificant change during the baseline phase, while the level of depression increased significantly. In contrast, the study demonstrated significant decreases in anxiety and depression as well as increases in positive self-concept (p=.001, p<.001, p=.017) during the intervention phase. Furthermore, a subgroup analysis was completed on participants who demonstrated elevated anxiety (23.4%), and depression (29.7%), and below average self-concept (18.6%) at baseline (T2). The subgroup of anxious, depressed, or low self-concept participants who received the brisk-walking intervention demonstrated significant decreases in anxiety and depression, and significant increases in self-concept scores. Participants who engaged in brisk walking over 90 minutes per week reported decreased mean scores on anxiety (t=-2.395, p=.035) and depression (t=-2.142, p=.036) in contrast with those who engaged in brisk-walking time less than 90 minutes per week. Regarding the effects on participants whose anxiety, scores were within the normal range at baseline, there was demonstrated significant decrease in the level of anxiety when they increased their time on brisk walking before each term examination. Overall, the brisk-walking program was effective and feasible to promote adolescents’ mental health by decreasing anxiety and depression as well as elevating self-concept. It also helped adolescents from anxiety before term examinations.

Keywords: adolescents, anxiety, depression, self-concept

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Authors: Jemma Porrett

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Background: We present a literature review examining the research surrounding tick paralysis resulting in facial nerve palsy. A case of an intra-aural paralysis tick bite resulting in unilateral facial nerve palsy is also discussed. Methods: A novel case of otoacariasis with associated ipsilateral facial nerve involvement is presented. Additionally, we conducted a review of the literature, and we searched the MEDLINE and EMBASE databases for relevant literature published between 1915 and 2020. Utilising the following keywords; 'Ixodes', 'Facial paralysis', 'Tick bite', and 'Australia', 18 articles were deemed relevant to this study. Results: Eighteen articles included in the review comprised a total of 48 patients. Patients' ages ranged from one year to 84 years of age. Ten studies estimated the possible duration between a tick bite and facial nerve palsy, averaging 8.9 days. Forty-one patients presented with a single tick within the external auditory canal, three had a single tick located on the temple or forehead region, three had post-auricular ticks, and one patient had a remarkable 44 ticks removed from the face, scalp, neck, back, and limbs. A complete ipsilateral facial nerve palsy was present in 45 patients, notably, in 16 patients, this occurred following tick removal. House-Brackmann classification was utilised in 7 patients; four patients with grade 4, one patient with grade three, and two patients with grade 2 facial nerve palsy. Thirty-eight patients had complete recovery of facial palsy. Thirteen studies were analysed for time to recovery, with an average time of 19 days. Six patients had partial recovery at the time of follow-up. One article reported improvement in facial nerve palsy at 24 hours, but no further follow-up was reported. One patient was lost to follow up, and one article failed to mention any resolution of facial nerve palsy. One patient died from respiratory arrest following generalized paralysis. Conclusions: Tick paralysis is a severe but preventable disease. Careful examination of the face, scalp, and external auditory canal should be conducted in patients presenting with otalgia and facial nerve palsy, particularly in tropical areas, to exclude the possibility of tick infestation.

Keywords: facial nerve palsy, tick bite, intra-aural, Australia

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