Search results for: long–term (chronic) stress

Authors: S. K. Maanju, K. Saha, Sonam Yadav

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Rapid urbanization growth and multi-faceted regional level industrialization is posing serious threat to natural groundwater resource in State of Rajasthan which constitute major semi-arid part of India. The groundwater resources of the State are limited and cannot withstand the present rate of exploitation for quite a long time. Recharging of groundwater particularly in the western part, where annual precipitation does not exceed a few centimeters, is extremely slow and cannot replenish the exploited quantum. Hence, groundwater in most of the parts of this region has become an exhausting resource. In major parts water table is lowering down rapidly and continuously. The human beings of this semi-arid region are used to suffering from extreme climatic conditions of arid to semi-arid nature and acute shortage of water. The quality of groundwater too in many areas of this region is not up to the standards prescribed by the health organizations like WHO and BIS. This semi-arid region is one of the highly fluoride contaminated area of India as well as have excess, nitrates, sulphates, chlorides and total dissolved solids at various locations. Therefore, concerted efforts are needed towards sustainable development of groundwater in this State of India.

Keywords: Rajasthan, water, exploitation, sustainable, development and resource

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Authors: Abhinav Srivastava, Hima Harode, Chandan Kumar Saha

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The principal ingredient of an optical fiber is quartz glass. The quality of the optical fiber decreases if impure foreign substances are attached to its preform surface. If residual strain inside a preform is significant, it cracks with a small impact during drawing or transporting. Furthermore, damages and unevenness on the surface of an optical fiber base material break the fiber during drawing. The present work signifies that chlorine pre-treatment enhances mechanical properties of the optical fiber glass. FTIR (Fourier-Transform Infrared Spectroscopy) results show that chlorine gas chemically modifies the structure of silica clad; chlorine is known to soften glass. Metallic impurities on the preform surface likely formed volatile metal chlorides due to chlorine pretreatment at elevated temperature. The chlorine also acts as a drying agent, and therefore the preform surface is anticipated to be water deficient and supposedly avoids particle adhesion on the glass surface. The Weibull analysis of long length tensile strength demarcates a substantial shift in its knee. The higher dynamic fatigue n-value also indicated surface crack healing.

Keywords: mechanical strength, optical fiber glass, FTIR, Weibull analysis

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Authors: Mont Kumpugdee-Vollrath, Khaled Abdallah

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Liposomes and pegylated liposomes were widely used as drug delivery system in pharmaceutical field since a long time. However, in the former time, polyethylene glycol (PEG) was connected into phospholipid after the liposomes were already prepared. In this paper, we intend to study the possibility of applying phospholipids which already connected with PEG and then they were used to prepare liposomes. The model drug resveratrol was used because it can be applied against different diseases. Cholesterol was applied to stabilize the membrane of liposomes. The thin film technique in a laboratory scale was a preparation method. The liposomes were then characterized by nanoparticle tracking analysis (NTA), photon correlation spectroscopy (PCS) and light microscopic techniques. The stable liposomes can be produced and the particle sizes after filtration were in nanometers. The 2- and 3-chains-PEG-phospholipid (PL) caused in smaller particle size than the 4-chains-PEG-PL. Liposomes from PL 90G and cholesterol were stable during storage at 8 °C of 56 days because the particle sizes measured by PCS were almost not changed. There was almost no leakage of resveratrol from liposomes PL 90G with cholesterol after diffusion test in dialysis tube for 28 days. All liposomes showed the sustained release during measuring time of 270 min. The maximum release amount of 16-20% was detected with liposomes from 2- and 3-chains-PEG-PL. The other liposomes gave max. release amount of resveratrol only of 10%. The release kinetic can be explained by Korsmeyer-Peppas equation. 

Keywords: liposome, NTA, resveratrol, pegylation, cholesterol

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Authors: Mamie Y. Griffin, Pedro Coelhoso

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Employability skills of university graduates remain an ongoing topic for discussion and debate. Numerous studies highlight the expressed concerns of governments and industries about higher education’s ability to develop workforce-ready graduates. An often cited solution is the use of internships to equip students with necessary employability skills. The literature is well documented with studies from the perspectives of multiple entities including employers and university faculty, mostly in the western world. Fewer studies examine the perception of students, and even fewer studies are based on students in Gulf countries. This paper assesses the status of employability skills from the perspective of students within a United Arab Emirates (UAE) institution based on their completion of a semester-long work placement experience. Using a largely qualitative instrument, students reported the essential skills needed in the workplace, classroom activities that most prepared students to use such skills in the workplace, and the various challenges they encountered. Implications for academic and professional practitioners are discussed. Findings and recommendations are informative for curriculum development as well as economic and workforce development agencies.

Keywords: employability skills, work placement experience, Gulf countries, workforce preparedness, work placement

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Authors: Aynur Aker, Hasan Kaya

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In recent years, the use of the aluminum based alloys in the industry and technology are increasing. Alloying elements in aluminum have further been improving the strength and stiffness properties that provide superior compared to other metals. In this study, investigation of physical properties (microstructure, microhardness, tensile strength, electrical conductivity and thermal properties) in the Al-12.6wt.%Si-%2wt.Ni ternary alloy were investigated. Al-Si-Ni alloy was prepared in a graphite crucible under vacuum atmosphere. The samples were directionally solidified upwards with different growth rate (V) at constant temperature gradient G (7.73 K/mm). The microstructures (flake spacings, λ), microhardness (HV), ultimate tensile strength, electrical resistivity and thermal properties enthalpy of fusion and specific heat and melting temperature) of the samples were measured. Influence of the growth rate and flake spacings on microhardness, ultimate tensile strength and electrical resistivity were investigated and relationships between them were experimentally obtained by using regression analysis. According to results, λ values decrease with increasing V, but microhardness, ultimate tensile strength, electrical resistivity values increase with increasing V. Variations of electrical resistivity for cast samples with the temperature in the range of 300-1200 K were also measured by using a standard dc four-point probe technique. The enthalpy of fusion and specific heat for the same alloy was also determined by means of differential scanning calorimeter (DSC) from heating trace during the transformation from liquid to solid. The results obtained in this work were compared with the previous similar experimental results obtained for binary and ternary alloys.

Keywords: electrical resistivity, enthalpy, microhardness, solidification, tensile stress

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Authors: Navah Z. Ratzon, Talia Glick, Iris Manor

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Attention Deficit Hyperactivity Disorder (ADHD) is a chronic disorder that affects the sufferer’s functioning throughout life and in various spheres of activity, including driving. Difficulties in cognitive functioning and executive functions are often part and parcel of the ADHD diagnosis, and thus form a risk factor in driving. Studies examining the effectiveness of intervention programs for improving and rehabilitating driving in typical teenagers have been conducted in relatively small numbers; while studies on similar programs for teenagers with ADHD have been especially scarce. The aim of the present study has been to examine the effectiveness of a metacognitive occupational therapy intervention program for reducing risk factors in driving among teenagers with ADHD. The present study included 37 teenagers aged 17 to 19. They included 23 teenagers with ADHD divided into experimental (11) and control (12) groups; as well as 14 non-ADHD teenagers forming a second control group. All teenagers taking part in the study were examined in the Tel Aviv University driving lab, and underwent cognitive diagnoses and a driving simulator test. Every subject in the intervention group took part in 3 assessment meetings, and two metacognitive treatment meetings. The control groups took part in two assessment meetings with a follow-up meeting 3 months later. In all the study’s groups, the treatment’s effectiveness was tested by comparing monitoring results on the driving simulator at the first and second evaluations. In addition, the driving of 5 subjects from the intervention group was monitored continuously from a month prior to the start of the intervention, a month during the phase of the intervention and another month until the end of the intervention. In the ADHD control group, the driving of 4 subjects was monitored from the end of the first evaluation for a period of 3 months. The study’s findings were affected by the fact that the ADHD control group was different from the two other groups, and exhibited ADHD characteristics manifested by impaired executive functions and lower metacognitive abilities relative to their peers. The study found partial, moderate, non-significant correlations between driving skills and cognitive functions, executive functions, and perceptions and attitudes towards driving. According to the driving simulator test results and the limited sampling results of actual driving, it was found that a metacognitive occupational therapy intervention may be effective in reducing risk factors in driving among teenagers with ADHD relative to their peers with and without ADHD. In summary, the results of the present study indicate a positive direction that speaks to the viability of using a metacognitive occupational therapy intervention program for reducing risk factors in driving. A further study is required that will include a bigger number of subjects, add actual driving monitoring hours, and assign subjects randomly to the various groups.

Keywords: ADHD, driving, driving monitoring, metacognitive intervention, occupational therapy, simulator, teenagers

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Authors: Jelena Filipovic, Milenko Kosutic

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The dynamic way of life has the tendency to simplify and decrease preparing healthy, quick, cheap and safe meals. Spelt pasta is meeting most of these goals. Contrary to bread, pasta can be stored a long time without deterioration in flavour, odour and usability without losing quality. This paper deals with the chemical composition and content of fatty acids in flaxseed and spelt flour. Ratio of essential fatty acids ω-6/ω-3 is also analysed in spelt pasta and pasta with 0%, 10% and 20% flaxseed flour. Gas chromatography with mass spectrometry is used for carrying out a quantitative analysis of flaxseed flour, spelt flour and pasta liposoluble extracts. Flaxseed flour has a better fatty acid profile than spelt flour, with low levels of saturated fat (approximately 9g/100g), high concentration of linolenic acid (57g/100g) and lower content of linoleic acid (16g/100g), as well as superior ω-6/ω-3 ratio that is 1:4. Flaxseed flour in the share of 10% and 20% in spelt pasta positively contributes to the essential fatty acids daily intake recommended by nutritionists and the improvement of ω-6/ω-3 ratio (6,7:1 and 1:1.2). This paper points out that investigated pasta with flaxseed is a new product with improved functional properties due to high level of ω-3 fatty acids and it is acceptable for consumers in regard to sensory properties.

Keywords: flaxseed, spelt, fatty acids, ω-3/ω-6 ratio, pasta

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Authors: Shola Haruna Adeosun, F. Adebiyi Ajoke, Odedeji Adeoye

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Video billboard advertising by networks and brand switching was conceived out of inquisition at the huge billboard advertising expenditures made by the three major GSM network operators in Nigeria. The study was anchored on Lagos State Metropolis with a current census population over 1,000,000. From this population, a purposive sample of 400 was adopted, and the questionnaire designed for the survey was carefully allocated to members of this ample in the five geographical zones of the city so that each rung of the society was well represented. The data obtained were analyzed using tables and simple percentages. The results obtained showed that subscribers of these networks were hardly influenced by the video billboard advertisements. They overwhelmingly showed that rather than the slogans of the GSM networks carried on the video billboards, it was the incentives to subscribers as well as the promotional strategies of these organizations that moved them to switch from one network to another. These switching lasted only as long as the incentives and promotions were in effect. The results of the study also seemed to rekindle the age-old debate on media effects, by the unyielding schools of the theory of ‘all-powerful media’, ‘the limited effects media’, ‘the controlled effects media’ and ‘the negotiated media influence’.

Keywords: evaluation, impact, video billboard, marketing, services

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Authors: Rim Chang Hyon, Song Hak Jin, Song Kwang Hyok, Jong Ki Hun

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The calibration of the articulated arm coordinate measuring machine (AACMM) is key to improving calibration accuracy and saving calibration time. To reduce the time consumed for calibration, we should choose the proper calibration gauges and develop a reasonable calibration method. In addition, we should get the exact optimal solution by accurately removing the rough errors within the experimental data. In this paper, we present a calibration method of the portable coordinate measuring arm (PCMA) using the 1.2m long bar guage with cone-holes. First, we determine the locations of the bar gauge and establish an optimal objective function for identifying the structural parameter errors. Next, we make a mathematical model of the calibration algorithm and present a new mathematical method to remove the rough errors within calibration data. Finally, we find the optimal solution to identify the kinematic parameter errors by using Levenberg-Marquardt algorithm. The experimental results show that our calibration method is very effective in saving the calibration time and improving the calibration accuracy.

Keywords: AACMM, kinematic model, parameter identify, measurement accuracy, calibration

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Authors: Chen-Yu Chen, Wei-Mon Yan, Chi-Nan Lai, Jian-Hao Su

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The proton exchange membrane fuel cell (PEMFC) becomes more important as an alternative energy source recently. Maintaining proper water content in the membrane is one of the key requirements for optimizing the PEMFC performance. The planar membrane humidifier has the advantages of simple structure, low cost, low-pressure drop, light weight, reliable performance and good gas separability. Thus, it is a common external humidifier for PEMFCs. In this work, a planar membrane humidifier for kW-scale PEMFCs is developed successfully. The heat and mass transfer of humidifier is discussed, and its performance is analyzed in term of dew point approach temperature (DPAT), water vapor transfer rate (WVTR) and water recovery ratio (WRR). The DPAT of the humidifier with the counter flow approach reaches about 6°C under inlet dry air of 50°C and 60% RH and inlet humid air of 70°C and 100% RH. The rate of pressure loss of the humidifier is 5.0×10² Pa/min at the torque of 7 N-m, which reaches the standard of commercial planar membrane humidifiers. From the tests, it is found that increasing the air flow rate increases the WVTR. However, the DPAT and the WRR are not improved by increasing the WVTR as the air flow rate is higher than the optimal value. In addition, increasing the inlet temperature or the humidity of dry air decreases the WVTR and the WRR. Nevertheless, the DPAT is improved at elevated inlet temperatures or humidities of dry air. Furthermore, the performance of the humidifier with the counter flow approach is better than that with the parallel flow approach. The DPAT difference between the two flow approaches reaches up to 8 °C.

Keywords: heat and mass transfer, humidifier performance, PEM fuel cell, planar membrane humidifier

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Authors: Monthana Weerawatanakorn, Hajime Tamaki, Yonathan Asikin, Koji Wada, Makoto Takahashi, Chi-Tang Ho, Min-Hsiung Pan

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Rice bran and sugarcane are significant sources of wax containing policosanol (PC), the cholesterol-lowering nutraceutical available in the market. The processing of rice bran oil causes the loss of PC content into various waste products. Therefore, we hypothesise that defatted rice bran (DRB) as agricultural waste product and rice bran oil (RBO) retain a varying but significant amount of PC wax. Non-centrifugal cane sugar (NCS) or cane brown sugar has been consumed worldwide and possesses various health benefits. Since PC wax is mainly in the outer layer rinds of cane, PC contents of the granulated sugar are reduced due to the peeling step. The study aimed to increase PC contents of the granular brown sugar by adding wax extracted from DRB and RBO and to investigate the toxicity of the developed products. The results showed that the total PC contents including long chain aldehyde of products were increased to the maximum level of 147.97 mg/100 g and 40.14 mg/100 g for extracted wax and rice bran oil addition, respectively. PC content of RBO was found to be 96.93 mg/100 g. DRB is promising source of policosanol (6,044.7 mg/100 g). The 28-day toxicity evaluations of the developed sugar revealed no adverse effects on the liver, spleen or kidney.

Keywords: enrichment, sugarcane, policosanol, defatted rice bran, wax

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Authors: Sampada Katekar, Namdeo Hedaoo

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Cold Bituminous Emulsion Mixtures (CBEMs) are generally produced by mixing unheated aggregate, binder and filler at ambient temperature. Cold bituminous emulsion mixtures have several environmental and cost-effective benefits. But CBEMs offer poor early life properties too and they require long curing time to achieve maximum strength. The main focus of this study is to overcome inferiority of CBEMs by incorporating Rice Husk Ash (RHA) and Ordinary Portland Cement (OPC). In this study, RHA and OPC are substituted for conventional mineral filler in an increased percentage from 0 to 3% with an increment of 1%. Marshall stability, retained stability and tensile strength tests were conducted to evaluate the enhancement in performance of CBEMs. The experimental results have shown that Marshall stability and tensile strength of CBEMs increased significantly by replacing the conventional mineral filler with RHA and OPC. The addition of RHA and OPC in CBEMs result in a reduction in moisture induced damages. However, stability and tensile strength values of RHA modified CBEMs are higher than that of OPC modified CBEMs.

Keywords: cold bituminous emulsion mixtures, Marshall stability test, ordinary Portland cement, rice husk ash

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Authors: Smriti Gour, Neelam Pandey

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The objective of this study was to describe and analyse the mutual relationship between the coping mechanisms used by the families of a child with Autism Spectrum Disorder (ASD) and family dynamics and the effect sibling interactions have on the dynamics and coping mechanisms in an urban setup. In-depth interviews were conducted for 25 families, with 4 members each in the Delhi NCR area in India. The families who were interviewed had a younger child who had received a diagnosis of ASD between the ages of 5-12. The in-depth questionnaires contained open-ended questions and the interviews were conducted separately for the mother, father and the typically developing sibling. The key findings of the study suggested that lack of communication was a common factor in most families (n=19) leading to other difficulties like stress and relationship dysfunction. It also fostered a fallacious perception of the relationship dynamics in the family in most of the interviewed families and changed depending on the family member being interviewed. In families where the typically developing elder sibling had a good relationship with the autistic child, the family dynamics were found to be more stable, and the overall family well-being was better maintained. The coping mechanisms employed by the families were also more positive and tended to work better if the typically developing sibling maintained a positive and interactive relationship with the parents and the autistic child. The type of coping mechanisms had a major impact on the relationship between the parents and in dictating the dynamics of the family of the child with ASD. Spirituality, professional help, family support and household help emerged to be the most effective coping mechanisms for the families, with spirituality emerging to be the most positive and effective coping mechanism in the families interviewed.

Keywords: autism spectrum disorder, coping mechanism, family dynamics, parental relationships, siblings

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Authors: Niloofar Bahramian, Mohammad Atai, Mohammad Reza Naimi-Jamal

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Rule of mixtures is the simple analytical model is used to predict various properties of composites before design. The aim of this study was to demonstrate the benefits and limitations of the Rule-of-Mixtures (ROM) for predicting bending modulus of a continuous and unidirectional fiber reinforced composites using in dental applications. The Composites were fabricated from light curing resin (with and without silica nanoparticles) and modified and non-modified fibers. Composite samples were divided into eight groups with ten specimens for each group. The bending modulus (flexural modulus) of samples was determined from the slope of the initial linear region of stress-strain curve on 2mm×2mm×25mm specimens with different designs: fibers corona treatment time (0s, 5s, 7s), fibers silane treatment (0%wt, 2%wt), fibers volume fraction (41%, 33%, 25%) and nanoparticles incorporation in resin (0%wt, 10%wt, 15%wt). To study the fiber and matrix interface after fracture, single edge notch beam (SENB) method and scanning electron microscope (SEM) were used. SEM also was used to show the nanoparticles dispersion in resin. Experimental results of bending modulus for composites made of both physical (corona) and chemical (silane) treated fibers were in reasonable agreement with linear ROM estimates, but untreated fibers or non-optimized treated fibers and poor nanoparticles dispersion did not correlate as well with ROM results. This study shows that the ROM is useful to predict the mechanical behavior of unidirectional dental composites but fiber-resin interface and quality of nanoparticles dispersion play important role in ROM accurate predictions.

Keywords: bending modulus, fiber reinforced composite, fiber treatment, rule-of-mixtures

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Authors: Sie Long Kek, Wah June Leong, Kok Lay Teo

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Linear quadratic Gaussian model is a standard mathematical model for the stochastic optimal control problem. The combination of the linear quadratic estimation and the linear quadratic regulator allows the state estimation and the optimal control policy to be designed separately. This is known as the separation principle. In this paper, an efficient computational method is proposed to solve the linear quadratic Gaussian problem. In our approach, the Hamiltonian function is defined, and the necessary conditions are derived. In addition to this, the output error is defined and the least-square optimization problem is introduced. By determining the first-order necessary condition, the gradient of the sum squares of output error is established. On this point of view, the stochastic approximation approach is employed such that the optimal control policy is updated. Within a given tolerance, the iteration procedure would be stopped and the optimal solution of the linear-quadratic Gaussian problem is obtained. For illustration, an example of the linear-quadratic Gaussian problem is studied. The result shows the efficiency of the approach proposed. In conclusion, the applicability of the approach proposed for solving the linear quadratic Gaussian problem is highly demonstrated.

Keywords: iteration procedure, least squares solution, linear quadratic Gaussian, output error, stochastic approximation

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Authors: Dawit Dibekulu, Tesfaye Dagnew, Tesfamaryam G. Meskel

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Echoing with memories of loss and whispers of despair, this study delves into the poignant world of melancholy in Sisay Nigusu's contemporary Amharic novel, ‘Yäqənat Zār’ (‘Zār of Jealousy’). Employing a psychoanalytic lens focused on Freud and Klein's theories of mourning and melancholia, we explore the psychological depths of characters ravaged by grief. Through an interpretive paradigm and descriptive research design, we unpack the intricate tapestry of the novel, revealing how love's ashes morph into melancholic despair. The loss of loved ones, be it sudden death or betrayal, casts long shadows on the characters' souls, distorting their behavior and twisting their narratives. Altered thoughts, self-blame, and paralyzing yearning become their companions, weaving a tragic dance of longing and despair. ‘Yäqənat Zār’ serves as a powerful testament to the transformative power of storytelling, allowing us to navigate the labyrinthine paths of melancholia and gain a glimpse into the Ethiopian soul grappling with loss. This study not only sheds light on the individual's struggle with sadness but also illuminates the cultural fabric of grief and melancholia intricately woven into Ethiopian society.

Keywords: melancholy, loss, psychoanalysis, grief, identity

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Authors: Mestawot Beyene Tafese, Erika Kopp

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Sustainable development, aimed at meeting current needs while safeguarding the needs of future generations, is a global imperative. Higher education stands as a pivotal force in fostering sustainable values and behaviors. However, most scholars and governments primarily focus on environmental and economic aspects. Consequently, this study examines the distribution patterns of higher education for social sustainability. The study highlights overall annual scientific production trends, leading journals and countries in scientific publication, most researched topics, and frequently used keywords. The study utilized a bibliometric method with the aid of the R Studio program. The analysis reveals Sustainability (Switzerland) as the leading journal, with 292 articles published, followed by the International Journal of Sustainability in Higher Education, which published 186 articles. Additionally, the USA is identified as the leading country, with Spain ranking second in producing research related to higher education for socially sustainable development. Among the 54 African countries, only South Africa ranks 13th, contributing fifty-nine scientific articles. Furthermore, higher education for sustainability, sustainable education, sustainable development goals, etc., emerge as the most researched topics, while the term "higher education" is prevalent in 29% and "sustainability" in 28% of the documents. Notably, according to the analysis, social sustainability is the focus of only 3% of articles. This suggests that academics researching sustainable development and higher education have overlooked social sustainability, a crucial human component of sustainable development. Consequently, the researchers concluded that social academics who are interested in studying sustainable development and higher education should give priority to social sustainability.

Keywords: higher education, bibliometric analysis, social sustainability, sustainable development

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Authors: María Reveles-Miranda, Daniella Pacheco-Catalán

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Sierra Papacal commissary is located north of Merida, Yucatan, México, where the indigenous Maya population predominates. Due to its location, the region has an elevation of fewer than 4.5 meters above sea level, with a high risk of flooding associated with storms and hurricanes and a high vulnerability of infrastructure and housing in the presence of strong gusts of wind. In environmental contingencies, the challenge is providing an autonomous electrical supply using renewable energy sources that cover vulnerable populations' health, food, and water pumping needs. To address this challenge, a hybrid energy storage module is proposed for the emergency photovoltaic (PV) system of the community shelter in Sierra Papacal, Yucatán, which combines high-energy-density batteries and high-power-density supercapacitors (SC) in a single module, providing a quick response to energy demand, reducing the thermal stress on batteries and extending their useful life. Incorporating SC in energy storage modules can provide fast response times to power variations and balanced energy extraction, ensuring a more extended period of electrical supply to vulnerable populations during contingencies. The implemented control strategy increases the module's overall performance by ensuring the optimal use of devices and balanced energy exploitation. The operation of the module with the control algorithm is validated with MATLAB/Simulink® and experimental tests.

Keywords: batteries, community shelter, environmental contingencies, hybrid energy storage, isolated photovoltaic system, supercapacitors

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Authors: Anny Zambrano, German Gonzalez, Yair Quintero

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The continuum damage concept is used to study the interaction between hydraulic fractures and natural fractures, the objective is representing the path and relation among this two fractures types and predict its complex behavior without the need to pre-define their direction as occurs in other finite element applications, providing results more consistent with the physical behavior of the phenomenon. The approach uses finite element simulations through Abaqus software to model damage fracturing, the fracturing process by damage propagation in a rock. The modeling the phenomenon develops in two dimensional (2D) so that the fracture will be represented by a line and the crack front by a point. It considers nonlinear constitutive behavior, finite strain, time-dependent deformation, complex boundary conditions, strain hardening and softening, and strain based damage evolution in compression and tension. The complete governing equations are provided and the method is described in detail to permit readers to replicate all results. The model is compared to models that are published and available. Comparisons are focused in five interactions between natural fractures (NF) and hydraulic fractures: Fractured arrested at NF, crossing NF with or without offset, branching at intersecting NFs, branching at end of NF and NF dilation due to shear slippage. The most significant new finding is, that is not necessary to use pre-defined addresses propagation and stress condition can be evaluated as a dominant factor in the process. This is important because it can model in a more real way the generated complex hydraulic fractures, and be a valuable tool to predict potential problems and different geometries of the fracture network in the process of fracturing due to fluid injection.

Keywords: continuum damage, hydraulic fractures, natural fractures, complex fracture network, stiffness

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Authors: Catarina Bento, Ana Carolina Gonçalves, Fábio Jesus, Luís Rodrigues Silva

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Increasing evidence suggests that a diet rich in fruits and vegetables plays important roles in the prevention of chronic diseases, such as heart disease, cancer, stroke, diabetes, Alzheimer’s disease, among others. Fruits and vegetables gained prominence due their richness in bioactive compounds, being the focus of many studies due to their biological properties acting as health promoters. Prunus avium Linnaeus (L.), commonly known as sweet cherry has been the centre of attention due to its health benefits, and has been highly studied. In Portugal, most of the cherry production comes from the Fundão region. The Saco is one of the most important cultivar produced in this region, attributed with geographical protection. In this work, we prepared 3 extracts through solid-phase extraction (SPE): a whole extract, fraction I (non-coloured phenolics) and fraction II (coloured phenolics). The three extracts were used to determine the phenolic profile of Saco cultivar by liquid chromatography with diode array detection (LC-DAD) technique. This was followed by the evaluation of their biological potential, testing the extracts’ capacity to scavenge free-radicals (DPPH•, nitric oxide (•NO) and superoxide radical (O2●-)) and to inhibit α-glucosidase enzyme of all extracts. Additionally, we evaluated, for the first time, the protective effects against peroxyl radical (ROO•)-induced hemoglobin oxidation and hemolysis in human erythrocytes. A total of 16 non-coloured phenolics were detected, 3-O-caffeoylquinic and ρ-coumaroylquinic acids were the main ones, and 6 anthocyanins were found, among which cyanidin-3-O-rutinoside represented the majority. In respect to antioxidant activity, Saco showed great antioxidant potential in a concentration-dependent manner, demonstrated through the DPPH•,•NO and O2●-radicals, and greater ability to inhibit the α-glucosidase enzyme in comparison to the regular drug acarbose used to treat diabetes. Additionally, Saco proved to be effective to protect erythrocytes against oxidative damage in a concentration-dependent manner against hemoglobin oxidation and hemolysis. Our work demonstrated that Saco cultivar is an excellent source of phenolic compounds which are natural antioxidants that easily capture reactive species, such as ROO• before they can attack the erythrocytes’ membrane. In a general way, the whole extract showed the best efficiency, most likely due to a synergetic interaction between the different compounds. Finally, comparing the two separate fractions, the coloured fraction showed the most activity in all the assays, proving to be the biggest contributor of Saco cherries’ biological activity.

Keywords: biological potential, coloured phenolics, non-coloured phenolics, sweet cherry

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Authors: Michael Bellas, George Voulgaridis

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This paper refers to the world known mega - landslide induced at the community of Ropoto, belonging to the Municipality of Trikala, in the Central part of Greece. The landslide affected the debris as well as the colluvium mantle of the flysch, and makes up a special case of study in engineering geology and geotechnical engineering not only because of the size of the domain affected by the landslide (approximately 750m long), but also because of the geostructure’s global behavior. Due to the landslide, the whole community’s infrastructure massively collapsed and human lives were put in danger. After the complete simulation of the coupled Seepage - Deformation phenomenon due to the extreme rainfall, and by closely examining the slope’s global behavior, both the mitigation of the landslide, as well as, an advanced surveillance method (Fiber Bragg Grating) using fiber optics were further studied, in order both to retain the geostructure and to monitor its health by creating an early warning system, which would serve as a complete safety net for saving both the community’s infrastructure as well as the lives of its habitats.

Keywords: landslide, remediation measures, the finite element method (FEM), Fiber Bragg Grating (FBG) sensing method

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Authors: Hei Yuen Pak

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Steer Toward Rock, Fae Myenne Ng’s second novel after the National Bestseller Bone, is superficially concluded as a story of pessimism, which underestimates the sophistication of Ng’s portrayal. It is often summarized as a “heartbreaking novel of unrequited love” or “a story of timeless and tragic”; yet, Ng’s novel conveys more than a mere sense of tragedy and heartbreak, but rather an overflowing warmth and optimism. Ng is complimented of “illuminating a part of U.S. history few are aware of”—the false identity established on the paper relationships. Nevertheless, toward the end of the novel, this falsity enlightens the male protagonist, Jack Moon Szeto, of the ultimate realization of the “truthfulness” to himself, with the escort of the female characters. This paper intends to investigate how Ng’s depiction subverts the traditional sex/gender system and also the patriarchal savior stereotype. This paper mainly examines the characterization of and the relations among the four major characters: Jack Moon Szeto, Joice Qwan, Veda Qwan, and Ilin Cheung. By deploying Kate Millett’s, Marilyn French’s, Mary Daly’s feminist theories, the first half of the essay elucidates the power relations between Jack and the three females Joice, Veda, and Ilin in terms of gender and sexuality. After analyzing the relations, Jack, this male caged bird, is set free by the epiphany derived from the three female characters, which is the pivot of the second half. In reference to Jean-Paul Sartre and Simone de Beauvoir’s existentialist perspectives, I argue how Jack is transformed from, in Satre’s term, being-for-others to being-for-itself. Hence, the caged bird is free by the women saviors.

Keywords: Fae Myenne Ng, gender and sexuality, feminism, power relations

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Authors: Christine H. Cubelo

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This study consists of 2-parts: a systematic review of current publications on the therapeutic use of autonomous sensory meridian response (ASMR) and a within-subjects auditory training trial using ASMR videos. The main intent is to explore ASMR as potentially therapeutically beneficial for those with atypical sensory processing. Many hearing-related disorders and mood or anxiety symptoms overlap with symptoms of sensory processing issues. For this reason, inclusion and exclusion criteria of the systematic review were generated in an effort to produce optimal search outcomes and avoid overly confined criteria that would limit yielded results. Criteria for inclusion in the review for Part 1 are (1) adult participants diagnosed with hearing loss or atypical sensory processing, (2) inclusion of measures related to ASMR as a treatment method, and (3) published between 2000 and 2022. A total of 1,088 publications were found in the preliminary search, and a total of 13 articles met the inclusion criteria. A total of 14 participants completed the trial and post-trial questionnaire. Of all responses, 64.29% agreed that the duration of auditory training sessions was reasonable. In addition, 71.43% agreed that the training improved their perception of music. Lastly, 64.29% agreed that the training improved their perception of a primary talker when there are other talkers or background noises present.

Keywords: autonomous sensory meridian response, auditory training, atypical sensory processing, hearing loss, hearing aids

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Authors: A. B. Chehreh, M. Grätzel, M. Klein, J. P. Bergmann, F. Walther

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Friction stir welding (FSW) is an advantageous method in the thermal joining processes, featuring the welding of various dissimilar and similar material combinations, joining temperatures below the melting point which prevents irregularities such as pores and hot cracks as well as high strengths mechanical joints near the base material. The FSW process consists of a rotating tool which is made of a shoulder and a probe. The welding process is based on a rotating tool which plunges in the workpiece under axial pressure. As a result, the material is plasticized by frictional heat which leads to a decrease in the flow stress. During the welding procedure, the material is continuously displaced by the tool, creating a firmly bonded weld seam behind the tool. However, the mechanical properties of the weld seam are affected by the design and geometry of the tool. These include in particular microstructural and surface properties which can favor crack initiation. Following investigation compares the dynamic properties of FSW weld seams with conventional and stationary shoulder geometry based on load increase test (LIT). Compared to classical Woehler tests, it is possible to determine the fatigue strength of the specimens after a short amount of time. The investigations were carried out on a robotized welding setup on 2 mm thick EN AW 5754 aluminum alloy sheets. It was shown that an increased tensile and fatigue strength can be achieved by using the stationary shoulder concept. Furthermore, it could be demonstrated that the LIT is a valid method to describe the fatigue behavior of FSW weld seams.

Keywords: aluminum alloy, fatigue performance, fracture, friction stir welding

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Authors: S. Benbellil-Tafoughalt, J. M. Koene

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Growth strategies are often plastic and influenced by environmental conditions. Terrestrial gastropods are particularly affected by seasonal and climatic variables, and growth rate and size at maturity are key traits in their life history. Therefore, we investigated juvenile growth of Helix aperta snails under four combinations of temperature and photoperiod using two sets of young snails, born in the laboratory from adults collected in either the autumn (aestivating snails) or spring (active snails). Parental snails were collected from Bakaro (Northeastern Algeria). Higher temperature increased adult size and reduced time to reproduction. Long day photoperiod also increased the final body weight, but had no effect on the length of the growth period. The season of birth had significant effects on length of the growth period and weight of hatchings, whereas this weight difference disappeared by adulthood. The spring snails took less time to develop and reached similar adult body weight as the autumn snails. These differences may be due to differences in egg size or quality between the snails from different seasons. More rapid growth in spring snails results in larger snails entering aestivation, a period with size-related mortality in this species.

Keywords: growth, Hélix aperta, photoperiod, temperature

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Authors: Shadia Al-Bahlani, Khadija Al-Bulushi, Zuweina Al-Hadidi, Buthaina Al-Dhahl, Nadia Al-Abri

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Breast cancer is the most common cancer in women worldwide. Triple-Negative Breast Cancer (TNBC) is an aggressive type of breast cancer, which is defined by the absence of Estrogen (ER), Progesterone (PR) and human epidermal growth factor (Her-2) receptors. The calpain system plays an important role in many cellular processes including apoptosis, necrosis, cell signaling and proliferation. However, the role of calpain in cisplatin (CDDP)-induced apoptosis in TNBC cells is not fully understood. Here, TNBC (MDA-MB231) cells were treated with different concentration of CDDP (0, 20 & 40 µM) and calpain activation and apoptosis were measured by western blot and Hoechst Stain respectively. In addition, calpain modulation by either activation and/or inhibition and its effect on CDDP-induced apoptosis were assessed by the same above approaches. Our findings showed that CDDP induced endoplasmic reticulum stress and thus Calcium release and subsequently activate calpain α-fodrin cleavage indicated by the increase in GRP78 and Calmodulin protein expression and respectively in MDA-MB231 cells. It also induced apoptosis as measured by Hoechst stain and caspase-12 cleavage. Calpain activation by both Cyclopiazonic acid and Thapsigargin showed similar effect and enhanced the sensitivity of these cells to CDDP treatment. On the other hand, calpain inhibition by either specific siRNA and/or exogenous inhibitor (Calpeptin) had an adverse effect where it attenuated calpain activation and thus CDDP- induced apoptosis in these cells. Altogether, these findings suggested that calpain activation play an essential role in sensitizing the TNBC cells to CDDP-induced apoptosis. This might lead to the discovery of novel treatment to over this aggressive type of breast cancer.

Keywords: calpain, cisplatin, apoptosis, breast cancer

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Authors: Frederick Johnson

Abstract:

Product management has a long and well-established history within the consumer goods industry, despite being one of the most obscure aspects of brand management. Many global manufacturing organizations are now opting for external cloud-based Manufacturing Execution Systems (MES) to replace costly and outdated monolithic MES solutions. Other global manufacturing leaders are restructuring their organizations to support human-centered values, agile methodologies, and fluid operating principles. Still, industry-leading organizations struggle to apply the appropriate framework for managing evolving external MES solutions as internal "digital products." Product management complements these current trends in technology and philosophical thinking in the market. This paper discusses the central problems associated with adopting product management processes by analyzing its traditional theories and characteristics. Considering these ideas, the article then constructs a translated internal digital product management framework by combining new and existing approaches and principles. The report concludes by demonstrating the framework's capabilities and potential effectiveness in achieving digital maturity and business agility within a manufacturing environment.

Keywords: internal product management, digital transformation, manufacturing information technology, manufacturing execution systems

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Authors: Lucia Perez, Maria Gaton y Santa Palella

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Starting from the etymology of the word culture, the Latin term ‘colere’, whose meaning is to cultivate, we understand that the society that cultivates its knowledge is laying the foundations for new possibilities. In this sense, art and fashion contain the same attributes: concept, aesthetic principles, and refined techniques. Both play a crucial role, communication, and this implies a sense of community, relationship with tradition, and innovation. This is the mirror in which to contemplate, but also the space that helps to grow. This is the framework where our object of study opens up: the anthropological management or the mission management model applied to fashion exhibitions in museums and cultural institutions. For this purpose, a bibliographic review has been carried out with its subsequent analysis, a case study of three successful exhibitions: ‘Christian Dior: designer of dreams’, ‘Balenciaga and the Spanish painting’, and ‘China: Through the Looking Glass’. The methodology has been completed with interviews focused on the curators. Amongst the results obtained, it is worth highlighting the fundamental role of transcendent leadership, which, in addition to being results-oriented, must align the motivations of the collaborators with the mission. The anthropological management model conceives management as a service, and it is oriented to the interests of the staff and the public, in short, of the person; this is what enables the objectives of effectiveness, efficiency, and social value to be achieved; dimensions, all necessary for the proper development of the mission of the exhibitions. Fashion, understood as art, is at the service of culture, and therefore of the human being, which defines a transcendent mission. We conclude that the profile of an anthropological management model applied to fashion exhibitions in museums is the ideal one to achieve the purpose of these institutions.

Keywords: art, culture, fashion, anthropological model, fashion exhibitions

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Authors: Long Chen

Abstract:

With the proliferation of E-Learning, collaborative learning becomes more and more popular in various teaching and learning occasions. Studies over the years have proved that actively participating in classroom discussion can enhance student's learning experience, consolidating their knowledge and understanding of the class content. Collaborative learning can also allow students to share their resources and knowledge by exchanging, absorbing, and observing one another's opinions and ideas. Community Question Answering (CQA) services are particularly suitable paradigms for collaborative learning, since it is essentially an online collaborative learning platform where one can get information from multiple sources for he/her to choose from. However, current CQA services have only achieved limited success in collaborative learning due to the uncertainty of answers' quality. In this paper, we predict the quality of answers in a CQA service, i.e. Yahoo! Answers, for the use of online education and distance learning, which would enable a student to find relevant answers and potential answerers more effectively and efficiently, and thus greatly increase students' user experience in CQA services. Our experiment reveals that the quality of answers is influenced by a series of factors such as asking time, relations between users, and his/her experience in the past. We also show that by modelling user's profile with our proposed personalized features, student's satisfaction towards the provided answers could be accurately estimated.

Keywords: Community Question Answering, Collaborative Learning, Log File, Co-Training

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Authors: Joselito Medina-Marin, Maria G. Serna-Diaz, Juan C. Seck-Tuoh-Mora, Norberto Hernandez-Romero, Irving Barragán-Vite

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Wind speed forecasting is an important issue for planning wind power generation facilities. The accuracy in the wind speed prediction allows a good performance of wind turbines for electricity generation. A model based on artificial neural networks is presented in this work. A dataset with atmospheric information about air temperature, atmospheric pressure, wind direction, and wind speed in Pachuca, Hidalgo, México, was used to train the artificial neural network. The data was downloaded from the web page of the National Meteorological Service of the Mexican government. The records were gathered for three months, with time intervals of ten minutes. This dataset was used to develop an iterative algorithm to create 1,110 ANNs, with different configurations, starting from one to three hidden layers and every hidden layer with a number of neurons from 1 to 10. Each ANN was trained with the Levenberg-Marquardt backpropagation algorithm, which is used to learn the relationship between input and output values. The model with the best performance contains three hidden layers and 9, 6, and 5 neurons, respectively; and the coefficient of determination obtained was r²=0.9414, and the Root Mean Squared Error is 1.0559. In summary, the ANN approach is suitable to predict the wind speed in Pachuca City because the r² value denotes a good fitting of gathered records, and the obtained ANN model can be used in the planning of wind power generation grids.

Keywords: wind power generation, artificial neural networks, wind speed, coefficient of determination

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