Search results for: small scale effect

Authors: Robbie C. Murchison, Ibrahim Küçükdemiral, Andrew Cowell

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Thermal effects are the largest source of dimensional error in precision machining, and a major proportion is caused by ambient temperature variation. The use of coolant is a primary means of mitigating these effects, but there has been limited work on coolant temperature control. This research critically explored whether CNC-machine coolant refrigeration systems adapted to actively compensate for ambient temperature variation could increase machining accuracy. Accuracy data were collected from operators’ checklists for a CNC 5-axis mill and statistically reduced to bias and precision metrics for observations of one day over a sample period of 27 days. Temperature data were collected using three USB dataloggers in ambient air, the chiller inflow, and the chiller outflow. The accuracy and temperature data were analysed using Pearson correlation, then the thermodynamics of the system were described using system identification with MATLAB. It was found that 75% of thermal error is reflected in the hot coolant temperature but that this is negligibly dependent on ambient temperature. The effect of the coolant refrigeration process on hot coolant outflow temperature was also found to be negligible. Therefore, the evidence indicated that it would not be beneficial to adapt coolant chillers to compensate for ambient temperature variation. However, it is concluded that hot coolant outflow temperature is a robust and accessible source of thermal error data which could be used for prevention strategy evaluation or as the basis of other thermal error strategies.

Keywords: CNC manufacturing, machine-tool, precision machining, thermal error

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Authors: Rachid El Aidani, Phuong Nguyen-Tri, Toan Vu-Khanh

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The filter media in synthetic fibre is the most geotextile materials used in aerosol and drainage filtration, particularly for buildings soil reinforcement in civil engineering due to its appropriated properties and its low cost. However, the current understanding of the durability and stability of this material in real service conditions, especially under severe long-term conditions are completely limited. This study has examined the effects of the chemical aging of a filter media in polyester nonwoven under different temperatures (50, 70 and 80˚C) and pH (2. 7 and 12). The effect of aging conditions on mechanical properties, morphology, permeability, thermal stability and molar weigh changes is investigated. The results showed a significant reduction of mechanical properties in term of tensile strength, puncture force and tearing forces of the filter media after chemical aging due to the chemical degradation. The molar mass and mechanical properties changes in different temperature and pH showed a complex dependence of material properties on environmental conditions. The SEM and AFM characterizations showed a significant impact of the thermal aging on the morphological properties of the fibres. Based on the obtained results, the lifetime of the material in different temperatures was determined by the use of the Arrhenius model. These results provide useful information to better understand phenomena occurring during chemical aging of the filter media and may help to predict the service lifetime of this material in real used conditions.

Keywords: nonwoven membrane, chemical aging, mechanical properties, lifetime, filter media

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Authors: O. I. Papagianni, P. Potsaki, K. Almpounioti, D. Chatzicharalampous, A. Voutsa, O. Katira, A. Michalaki, H. C. Karantonis, A. E. Koutelidakis

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High intakes of carbohydrates and fats have been associated with an increased risk of chronic diseases due to the role of postprandial oxidative stress. This pilot nutritional intervention aimed to examine the acute effect of consuming two different types of breadsticks prepared from durum wheat flour mixtures differing in total phenolic content on postprandial inflammatory and oxidant responses in healthy volunteers. A cross-over, controlled, and single-blind clinical trial was designed, and two isocaloric high-fat and high-carbohydrate meals were tested. Serum total, HDL- and LDL-cholesterol, triglycerides, glucose, CRP, uric acid, plasma total antioxidant capacity, and antiplatelet activity were determined in fasting and 30, 60, and 120 min after consumption. The results showed a better postprandial HDL-cholesterol and total antioxidant activity response in the intervention group. The choice of durum wheat flours with higher phenolic content and antioxidant activity is presented as promising for human health, and clinical studies will expand to draw safer conclusions.

Keywords: breadsticks, durum wheat flours, postprandial inflammation, postprandial oxidative stress, ex vivo antiplatelet activity

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Authors: Thanura Randula Abeywardena

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This study recognized the effectiveness of cold-water immersion recovery post exhaustive short-term exercise. The purpose of this study was to understand if 16- 20°C of cold-water immersion would be beneficial in a tropical environment to achieve optimal recovery in sprint swim performance in comparison to 10-15°C of water immersion. Two 100m-sprint swim performance times were measured along with blood lactate (BLa), heart rate (HR) and rate of perceived exertion (RPE) in a 25m swimming pool with full body head out horizontal water immersions of 10-15°C, 16-20°C and 29-32°C (pool temperature) for 10 minutes followed by 5 minutes of seated passive rest outside; in between the two swim performances. Twelve well-trained adult swimmers (5 male and 5 female) within the top twenty in the Sri Lankan national swimming championships in 100m Butterfly and Freestyle in the years 2020 & 2021 volunteered for this study. One-way ANOVA analysis (p<0.05) suggested performance time, Bla and HR had no significant differences between the 3 conditions after the second sprint; however, RPE was significantly different with p=0.034 between 10-15°C and 16-20°C immersion conditions. The study suggested that the recovery post the two cold-water immersion conditions were similar in terms of performance and physiological factors; however, the 16-20°C temperature had a better “feel good” factor post sprint 2. Further study is recommended as there was participant bias with the swimmers not reaching optimal levels in sprint 1. Therefore, they might have possibly fully recovered before sprint 2, invalidating the physiological effect of recovery.

Keywords: hydrotherapy, blood lactate, fatigue, recovery, sprint-performance, sprint-swimming

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Authors: Bindu Kumari, Bindu Kumari Singh

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Endosulfan is known to be one of the highly toxic agricultural pesticides commonly used in our societies. With the widespread use of Endosulfan in agriculture, human beings are most likely to be exposed to it, either orally by eating Endosulfan-contaminated foods or by nose and whole body inhalation in the farms during its application. The present study was conducted to observe the changes in the serum uric acid level of the Swiss albino rats due to the administration of Endosulfan. 3.0 mg Endosulfan/kg body weight was daily administered orally to albino rats for 28 days period. Alterations in their K.F.T. parameters were recorded at a regular interval of 7 days within this 28 days period and were compared with those of control rats. All rats were monitored for any observable toxic symptoms throughout the experimental period and they also were weighted weekly to monitor body weight gain. Alteration recorded in K.F.T. parameters within the groups were due to Endosulfan exposure and serum uric acid level was significantly elevated in the 3mg/kg dose group. Pathological changes of rats treated with Endosulfan were observed with typical signs of toxicity. Uric acid is a heterocyclic compound formed as an end product of metabolism of purine nucleotides. It forms ions and salts known as urate and acid urate which are harmful to our health. Uric acid clearance is one of the numerous important functions of the kidney. Defects in this process resulted in Gout, kidney stone or Kidney failure.

Keywords: KFT parameters, blood uric acid level, endosulfan, eat

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Authors: Tomaz Oliveira, Rui Medeiros, André Lacerda

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Introduction: Cleft lip and/or palate are the most frequent forms of congenital craniofacial anomalies, affecting mainly the middle third of the face and manifesting by functional and aesthetic changes. Bilateral cleft lip represents a reconstructive surgical challenge, not only for the labial component but also for the associated nasal deformation. Recently, the paradigm of the approach to this pathology has changed, placing the focus on muscle reconstruction and anatomical repositioning of the nasal cartilages in order to obtain the best aesthetic and functional results. The aim of this study is to carry out a systematic review of the surgical approach to bilateral cleft lip, retrospectively analyzing the case series of Plastic Surgery Service at Hospital Santa Maria (Lisbon, Portugal) regarding this pathology, the global assessment of the characteristics of the operated patients and the study of the different surgical approaches and their complications in the last 20 years. Methods: The present work demonstrates a retrospective and descriptive study of patients who underwent at least one reconstructive surgery for cleft lip and/or palate, in the CPRE service of the HSM, in the period between January 1 of 1997 and December 31 of 2017, in which the data relating to 361 individuals were analyzed who, after applying the exclusion criteria, constituted a sample of 212 participants. The variables analyzed were the year of the first surgery, gender, age, type of orofacial cleft, surgical approach, and its complications. Results: There was a higher overall prevalence in males, with cleft lip and cleft palate occurring in greater proportion in males, with the cleft palate being more common in females. The most frequently recorded malformation was cleft lip and palate, which is complete in most cases. Regarding laterality, alterations with a unilateral labial component were the most commonly observed, with the left lip being described as the most affected. It was found that the vast majority of patients underwent primary intervention up to 12 months of age. The surgical techniques used in the approach to this pathology showed an important chronological variation over the years. Discussion: Cleft lip and/or palate is a medical condition associated with high aesthetic and functional morbidity, which requires early treatment in order to optimize the long-term outcome. The existence of a nasolabial component and its respective surgical correction plays a central role in the treatment of this pathology. The high rates of post-surgical complications and unconvincing aesthetic results have motivated an evolution of the surgical technique, increasingly evident in recent years, allowing today to achieve satisfactory aesthetic results, even in bilateral cleft lip with high deformation complexity. The introduction of techniques that favor nasolabial reconstruction based on anatomical principles has been producing increasingly convincing results. The analyzed sample shows that most of the results obtained in this study are, in general, compatible with the results published in the literature. Conclusion: This work showed that the existence of small variations in the surgical technique can bring significant improvements in the functional and aesthetic results in the treatment of bilateral cleft lip.

Keywords: cleft lip, palate lip, congenital abnormalities, cranofacial malformations

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Authors: Ngo Xuan Quang, Tran Thanh Thai, Ann Vanreusel

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The Ba Lai dam construction was created in 2000 in the Ba Lai estuarine river, Ben Tre province, Vietnam to prevent marine water infiltration, drainage and de-acidification, and to build a reservoir of freshwater for land reclamation in the Ba Lai tributary. However, this dam is considered as an environmental failure for the originally connected estuarine and river ecosystem, especially to bad effect to benthic fauna distribution. This research aims to study applying free living nematode communities’ distribution in disturbance of dam construction as bioindicator to detect environmental impact. Nematode samples were collected together measuring physical–chemical environmental parameters such as chlorophyll, CPE, coliform, nutrient, grain size, salinity, dissolved oxygen, turbidity, conductivity, temperature in three stations within three replicates. Results showed that free living nematode communities at the dam construction was significantly low densities, low diversity (Hurlbert’s index, Hill diversity indices) and very low maturity index in comparison with two remaining stations. Strong correlation of nematode feeding types and communities’ structure was found in relation with sediment grain size and nutrient enrichment such nitrite, nitrate, phosphate and pigment concentration. Moreover, greatly negative link between nematode maturity index with nutrient parameters can serve as warning organic pollution of the Ba Lai river due to dam construction.

Keywords: Ba Lai, dam impact, nematode, environment

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Authors: Yasemin Gülşen Yılmaz, Süleyman Hakan Yılmaz, Muhammet Erbay

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Military interventions have an important place in the Turkish Political History. Military interventions are commonly called coup in the society. By coup we mean that the armed forces seize political power either by a group of officer in the army or by chain of command. Coups not only weaken but also suspend the democracy in a country. All periods of coup created its own victims. Two military coups which took place in May 27, 1960 and September 12, 1980 are the most important ones in terms of political and social effect in the Turkish Political History. Apart these, March 12, 1971, February 28, 1997 and April 27, 2007 e-memorandum are the periods when Army submitted a memorandum and intervened the political government indirectly. Beside the memorandums and coups there were also many coup attempts that have been experienced in the Turkish Political History. In this study, we examined the coup attempted by FETO’s military members in the evening of July 15, 2016 from the point of the Turkish Press. Cumhuriyet, Haber Türk, Hürriyet, Milliyet, Sabah, Star, Yeni Akit and Yeni Şafak Newspapers which have different publication policies were examined within the scope of the study. The first pages of the newspapers dated July 16, 2016 were examined using content analysis method. The headlines, news, news headlines and the visual materials used for news were examined and the collected data were analysed.

Keywords: July 15, news, military coup, press

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Authors: Chao Hsing Yeh, Wei Chun Lin

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Background: Current management of aromatase inhibitor-induced arthralgia (AIA) in postmenopausal breast cancer survivors (PBCS) has limited effect. Method: In this prospective randomized clinical trial (RCT), a 4-week APA treatment was used to manage AIA. Twenty PBCS participated. After baseline data was collected, participants were waited for a month before they receive APA at a convenient time once a week for 4 weeks. Blood samples from participants in both groups were collected at baseline and after 4 weeks of treatment. The primary outcomes included: pain intensity, pain interference, stiffness, and physical function. Results: After the 4-week APA treatment, the pro-inflammatory cytokines and chemokines display a trend of mean percentage reduction (i.e., -22% in IL-1α, -4% in IL-1β, -1% in IL-2, -3% in IL-6, -19% in IL-12, -9% in Eotaxin, and -2% in MCP-1). The anti-inflammatory cytokine IL-10 and IL-13 (i.e., 5% in IL-10 and 29% in IL-13) increased from pre- to post-APA treatment. Significant positive correlation of percentage mean change was observed between symptom severity and eotaxin (ρ = 0.56; p < 0.01) & MCP-1 (ρ = 0.65; p < 0.01). Interference and chemokines (eotaxin & MIP-1) also shows positive correlation (ρ = 0.48; p < 0.01 & ρ = 0.39; p < 0.05). Another positive correlation was found between worst pain and chemokines (eotaxin, ρ = 0.48; p < 0.01 & MIP-1, ρ = 0.39; p < 0.05). Additionally, interference also shows positive correlation among IL-1α (ρ = 0.36; p < 0.05) and IL-β (ρ = 0.33; p < 0.05). Conclusion: These findings suggest that APA intervention may inhibit inflammation of AIA patients and chemokine could be one of the key factors of AIA symptom improvement.

Keywords: acupressure, cytokine, pain management, breast cancer survivors

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Authors: Mahsa Oroojeni Mohammad Javad

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Globalization of economic activity and rapid growth of information technology has resulted in shorter product lifecycles, reduced transport capacity, dynamic and changing customer behaviors, and an increased focus on supply chain design in recent years. The design of the supply chain network is one of the most important supply chain management decisions. These decisions will have a long-term impact on the efficacy and efficiency of the supply chain. In this paper, a two-objective mixed-integer linear programming (MILP) model is developed for designing and optimizing a closed-loop green supply chain network that, to the greatest extent possible, includes all real-world assumptions such as multi-level supply chain, the multiplicity of production technologies, and multiple modes of transportation, with the goals of minimizing the total cost of the chain (first objective) and minimizing total emissions of emissions (second objective). The ε-constraint and CPLEX Solver have been used to solve the problem as a single-objective problem and validate the problem. Finally, the sensitivity analysis is applied to study the effect of the real-world parameters’ changes on the objective function. The optimal management suggestions and policies are presented.

Keywords: closed-loop supply chain, multi-level green supply chain, mixed-integer programming, transportation modes

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Authors: Mohammed T. Hayajneh

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Machining of Metal Matrix Composites (MMCs) is very significant process and has been a main problem that draws many researchers to investigate the characteristics of MMCs during different machining process. The poor machining properties of hard particles reinforced MMCs make drilling process a rather interesting task. Unlike drilling of conventional materials, many problems can be seriously encountered during drilling of MMCs, such as tool wear and cutting forces. Cutting tool wear is a very significant concern in industries. Cutting tool wear not only influences the quality of the drilled hole, but also affects the cutting tool life. Prediction the cutting tool life during drilling is essential for optimizing the cutting conditions. However, the relationship between tool life and cutting conditions, tool geometrical factors and workpiece material properties has not yet been established by any machining theory. In this research work, fuzzy subtractive clustering system has been used to model the cutting tool life in drilling of Al₂O₃ particle reinforced aluminum alloy composite to investigate of the effect of cutting conditions on cutting tool life. This investigation can help in controlling and optimizing of cutting conditions when the process parameters are adjusted. The built model for prediction the tool life is identified by using drill diameter, cutting speed, and cutting feed rate as input data. The validity of the model was confirmed by the examinations under various cutting conditions. Experimental results have shown the efficiency of the model to predict cutting tool life.

Keywords: composite, fuzzy, tool life, wear

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Authors: Bo Jin

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A variety of process equipment having flow in and out is widely used in industrial land-based cryogenic facilities. In some of this equipment, such as vapor-liquid separator, a liquid level is established during the steady operation. As the implementation of such industrial processes extends to off-shore floating facilities, it is important to investigate the effect of sea motion on the process equipment partially filled with liquid. One important aspect to consider is the occurrence of sloshing therein. The flow characteristics are different from the classical study of sloshing, where the fluid is enclosed inside a vessel (e.g., storage tank) with no flow in or out. Liquid inside process equipment continuously flows in and out of the system. To understand this key difference, a Computational Fluid Dynamics (CFD) model is developed to simulate the liquid motion inside a partially filled cylinder with and without continuous flow in and out. For a partially filled vertical cylinder without any continuous flow in and out, the CFD model is found to be able to capture the well-known sloshing behavior documented in the literature. For the cylinder with a continuous steady flow in and out, the CFD simulation results demonstrate that the continuous flow suppresses sloshing. Given typical cryogenic fluid has very low viscosity, an analysis based on potential flow theory is developed to explain why flow into and out of the cylinder changes the natural frequency of the system and thereby suppresses sloshing. This analysis further validates the CFD results.

Keywords: computational fluid dynamics, CFD, cryogenic process equipment, off-shore floating processes, sloshing

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Authors: Zhang Xin

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Barrier lakes are lakes formed by storing water in valleys, river valleys or riverbeds after being blocked by landslide, earthquake, debris flow, and other factors. They have great potential safety hazards. When the water is stored to a certain extent, it may burst in case of strong earthquake or rainstorm, and the lake water overflows, resulting in large-scale flood disasters. In order to ensure the safety of people's lives and property in the downstream, it is very necessary to monitor the barrier lake. However, it is very difficult and time-consuming to manually monitor the barrier lake in high altitude areas due to the harsh climate and steep terrain. With the development of earth observation technology, remote sensing monitoring has become one of the main ways to obtain observation data. Compared with a single satellite, multi-satellite remote sensing cooperative observation has more advantages; its spatial coverage is extensive, observation time is continuous, imaging types and bands are abundant, it can monitor and respond quickly to emergencies, and complete complex monitoring tasks. Monitoring with multi-temporal and multi-platform remote sensing satellites can obtain a variety of observation data in time, acquire key information such as water level and water storage capacity of the barrier lake, scientifically judge the situation of the barrier lake and reasonably predict its future development trend. In this study, The Sarez Lake, which formed on February 18, 1911, in the central part of the Pamir as a result of blockage of the Murgab River valley by a landslide triggered by a strong earthquake with magnitude of 7.4 and intensity of 9, is selected as the research area. Since the formation of Lake Sarez, it has aroused widespread international concern about its safety. At present, the use of mechanical methods in the international analysis of the safety of Lake Sarez is more common, and remote sensing methods are seldom used. This study combines remote sensing data with field observation data, and uses the 'space-air-ground' joint observation technology to study the changes in water level and water storage capacity of Lake Sarez in recent decades, and evaluate its safety. The situation of the collapse is simulated, and the future development trend of Lake Sarez is predicted. The results show that: 1) in recent decades, the water level of Lake Sarez has not changed much and remained at a stable level; 2) unless there is a strong earthquake or heavy rain, it is less likely that the Lake Sarez will be broken under normal conditions, 3) lake Sarez will remain stable in the future, but it is necessary to establish an early warning system in the Lake Sarez area for remote sensing of the area, 4) the coordinative remote sensing observation technology is feasible for the high altitude barrier lake of Sarez.

Keywords: coordinative observation, disaster, remote sensing, geographic information system, GIS

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Authors: Ebtissam Saleh Al-Meghaiseeb, Abdulaziz Al Masood, Abdulrahman Al-Robayan, Reem Al-Amro, Misbahul Arfin, Abdulrahman Al Asmari

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Objective: The objective of this study was to evaluate the role of apolipoprotein E (APOE) polymorphism on the onset of inflammatory bowel disease (IBD) in Saudi patients. Methods: APOE gene was genotyped to evaluate the frequencies of the alleles and genotypes in Saudi subjects, including IBD patients (n=200) and matched controls (n=200), using APOE StripAssayTM kit (ViennaLab Labordiagnostika GmbH, Vienna, Austria). Results: The frequencies of alleles and genotypes of APOE differed in patients and controls. The APOE allele ε2 and ε4, genotype ε2/ε3 and ε2/ε4 were significantly higher in the IBD patients than the healthy controls. The frequencies of ε3 allele and ε3/ε3 genotype were higher in the control group as compared to patients. The higher prevalence of allele ε2 and ε4 allele in patients compared to that in controls suggested that ε2 and ε4 alleles may increase the risk of IBD. Results also indicated that APOE ε4 allele was associated with early age at onset of IBD. On the other hand, the decreased frequencies of ε3 allele and ε3/ε3 genotype in patients as compared to those in the controls suggested a protective effect of APOE ε3 for IBD susceptibility. In this study, the frequency distribution of APOE alleles and genotypes was not affected by the gender or type of IBD (familial or sporadic). Conclusion: This study indicates that APOE polymorphism plays a significant role in developing IBD and early age of onset in Saudi patients. However, further studies with large-size sample are warranted to confirm this relationship.

Keywords: APOE, polymorphism, IBD, saudis

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Authors: John Monro, Suman Mishra

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Choosing foods for health benefits requires information that accurately represents the relative effectiveness of foods with respect to specific health end points, or with respect to responses leading to health outcomes. At present consumers must rely on nutrient composition data, and on health claims to guide them to healthy food choices. Nutrient information may be of limited usefulness because it does not reflect the effect of food structure and food component interactions – that is, whole food effects. Health claims demand stringent criteria that exclude most foods, even though most foods have properties through which they may contribute to positive health outcomes in a diet. In this presentation, we show how the functional efficacy of foods may be expressed in the same format as nutrients, with weight units, as virtual food components that allow a nutrition information panel to show not only what a food is, but also what it does. In the presentation, two body responses linked to well-being are considered – glycaemic response and colonic bulk – in order to illustrate the concept. We show how the nutrient information on available carbohydrates and dietary fibre values obtained by food analysis methods fail to provide information of the glycaemic potency or the colonic bulking potential of foods, because of failings in the methods and approach taken to food analysis. It is concluded that a category of food values that represent the functional efficacy of foods is required to accurately guide food choices for health.

Keywords: dietary fibre, glycaemic response, food values, food effects, health

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Authors: Pawan Kumar, Dhananjoy Shaw, Manoj Kumar Rathi

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Purpose of the study were to compare between (a) frequencies among the four quartiles of percentile norms of autonomic variables from power events and (b) frequencies among the four quartiles percentile norms of autonomic variables from aerobic events of Indian sportspersons withdrawn from competitive games and sports in regard to number of samples falling in each quartile. The study was conducted on 430 males of 30 to 35 years of age. Based on the nature of game/sports the retired sportspersons were classified into power events (throwers, judo players, wrestlers, short distance swimmers, cricket fast bowlers and power lifters) and aerobic events (long distance runners, long distance swimmers, water polo players). Date was collected using ECG polygraphs. Data were processed and extracted using frequency domain analysis and time domain analysis. Collected data were computed with frequency, percentage of each quartile and finally the frequencies were compared with the chi square analysis. The finding pertaining to norm reference comparison of frequencies among the four quartiles of Indian sportspersons withdrawn from competitive games and sports from (a) power events suggests that frequency distribution in four quartile namely Q1, Q2, Q3, and Q4 are significantly different at .05 level in regard to variables namely, SDNN, Total Power (Absolute Power), HF (Absolute Power), LF (Normalized Power), HF (Normalized Power), LF/HF ratio, deep breathing test, expiratory respiratory ratio, valsalva manoeuvre, hand grip test, cold pressor test and lying to standing test, whereas, insignificantly different at .05 level in regard to variables namely, SDSD, RMSSD, SDANN, NN50 Count, pNN50 Count, LF (Absolute Power) and 30: 15 Ratio (b) aerobic events suggests that frequency distribution in four quartile are significantly different at .05 level in regard to variables namely, SDNN, LF (Normalized Power), HF (Normalized Power), LF/HF ratio, deep breathing test, expiratory respiratory ratio, hand grip test, cold pressor test, lying to standing test and 30: 15 ratio, whereas, insignificantly different at .05 level in regard to variables namely, SDSD, RMSSD. SDANN, NN50 count, pNN50 count, Total Power (Absolute Power), LF(Absolute Power) HF(Absolute Power), and valsalva manoeuvre. The study concluded that comparison of frequencies among the four quartiles of Indian retired sportspersons from power events and aerobic events are different in four quartiles in regard to selected autonomic functions, hence the developed percentile norms are not homogenously distributed across the percentile scale; hence strengthen the percentage distribution towards normal distribution.

Keywords: power, aerobic, absolute power, normalized power

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Authors: Daodu Joshua Rotimi

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This study investigated the Efficacy of Self-Assessment Metacognitive Strategy on Academic performance in Energy Concepts among Upper Basic Science Students in Ankpa, Kogi State, Nigeria. The research design adopted for the study was a Quasi-experimental control group design which employed a pretest, posttest of the experimental and control groups. The population of the study consisted of one hundred and twenty-four (124) JSSII Students; sixty-five (65) for the experimental group and (59) for the control group. The instrument used for the study was the Energy Concept Performance Test (ECPT), with a reliability coefficient of 0.80. Two research questions were answered using descriptive statistics of mean and standard deviation, while two hypotheses were tested using a t-test at P≤0.05 level of significance. The findings of the study revealed that the use of the Self-Assessment Metacognitive Strategy has a positive effect on students’ performance in energy concepts among upper Basic Science Students leading to high academic performance; also, there is no significant difference in the mean Academic Performance scores between Male and Female students taught Energy Concept using Self-Assessment Metacognitive Strategy. Based on the research findings, recommendations were made, which include that Secondary school teachers should be encouraged the use Self-Assessment Metacognitive strategy so as to make the learning process attractive, interactive and enriching to the learners.

Keywords: metacognition, self-assessment, performance, efficacy

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Authors: Yasmin Umar Assegaf, Falikhatun, Salamah Wahyuni

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This study aims to provide empirical evidence about the influence of Islamic Corporate Social Responsibility Disclosures of the financial performance of Islamic banking with the characteristics of the company, as a control variable in Islamic banking in Indonesia. ICSR disclosures are an independent variable, while the Financial Performance is the dependent variable (proxied by Return on Assets (ROA), Return on Equity (ROE), Income Expense Ratio (IER), and Non-net Interest Margin (NIM). The control variables used are firm size, firm age and the type of audit. The population of the study was all Islamic Banks (BUS) operate in Indonesia. The research sample is Islamic Commercial Bank which has existed in Indonesia since 2002 and publishes financial statements between the years of 2007-2011. The sample of the study were include 31 Annual Report published. The results of this study concluded that there are significant influences between the ICSR Disclosures and financial performance. The disclosure is partially effect on ROA, IER and NIM, whereas there is no influence on ROE. Further result shows that all control variables (Firm Size, Age, and Type of Audit Companies) does not have any influence on ICSR Disclosures in Indonesia. This research gives a suggestion for further research to compare these ICSR disclosures in Indonesia with ICSR disclosures in other countries that have Islamic banking, by using other measure variables of financial performance, to get more comprehensive model and real picture.

Keywords: ROA, ROE, IER, NIM, company size, age of the company, audit type, Islamic banking

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Authors: Eliane Abdo, Olivier Colot

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SMEs are always considered as a national priority due to their contribution to job creation, innovation and growth. Once the start-up phase is crossed with encouraging results, the company enters the phase of growth. In order to improve its competitiveness, maintain and increase its market share, the company is in the necessity even the obligation to develop its tangible and intangible investments. SMEs are generally closed companies with special and critical financial situation, limited resources and difficulty to access the capital markets; their shareholders are always living in a conflict between their independence and their need to increase capital that leads to the entry of new shareholder. The capital structure was always considered the core of research in corporate finance; moreover, the financial crisis and its repercussions on the credit’s availability, especially for SMEs make SME financing a hot topic. On the other hand, financial theories do not provide answers to capital structure’s questions; they offer tools and mode of financing that are more accessible to larger companies. Yet, SME’s capital structure can’t be independent of their governance structure. The classic financial theory supposes independence between the investment decision and the financing decision. Thus, investment determines the volume of funding, but not the split between internal or external funds. In this context, we find interesting to study the hypothesis that SMEs respond positively to the financial theories applied to large firms and to check if they are constrained by conventional solutions used by large companies. In this context, this research focuses on the analysis of the resource’s structure of SME in parallel with their investments’ structure, in order to highlight a link between their assets and liabilities structure. We founded our conceptual model based on two main theoretical frameworks: the Pecking order theory, and the Trade Off theory taking into consideration the SME’s characteristics. Our data were generated from DIANE database. Five hypotheses were tested via a panel regression to understand the type of dependence between the financing methods of 3,244 French SMEs and the development of their investment over a period of 10 years (2007-2016). The results show dependence between equity and internal financing in case of intangible investments development. Moreover, this type of business is constraint to financial debts since the guarantees provided are not sufficient to meet the banks' requirements. However, for tangible investments development, SMEs count sequentially on internal financing, bank borrowing, and new shares issuance or hybrid financing. This is compliant to the Pecking Order Theory. We, therefore, conclude that unlisted SMEs incur more financial debts to finance their tangible investments more than their intangible. However, they always prefer internal financing as a first choice. This seems to be confirmed by the assumption that the profitability of the company is negatively related to the increase of the financial debt. Thus, the Pecking Order Theory predictions seem to be the most plausible. Consequently, SMEs primarily rely on self-financing and then go, into debt as a priority to finance their financial deficit.

Keywords: capital structure, investments, life cycle, pecking order theory, trade off theory

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Authors: Burak Oksuzoglu, Savas Yildirim, Ferhat Kutlu

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Opinion mining (OM) is one of the natural language processing (NLP) problems to determine the polarity of opinions, mostly represented on a positive-neutral-negative axis. The data for OM is usually collected from various social media platforms. In an era where social media has considerable control over companies’ futures, it’s worth understanding social media and taking actions accordingly. OM comes to the fore here as the scale of the discussion about companies increases, and it becomes unfeasible to gauge opinion on individual levels. Thus, the companies opt to automize this process by applying machine learning (ML) approaches to their data. For the last two decades, OM or sentiment analysis (SA) has been mainly performed by applying ML classification algorithms such as support vector machines (SVM) and Naïve Bayes to a bag of n-gram representations of textual data. With the advent of deep learning and its apparent success in NLP, traditional methods have become obsolete. Transfer learning paradigm that has been commonly used in computer vision (CV) problems started to shape NLP approaches and language models (LM) lately. This gave a sudden rise to the usage of the pretrained language model (PTM), which contains language representations that are obtained by training it on the large datasets using self-supervised learning objectives. The PTMs are further fine-tuned by a specialized downstream task dataset to produce efficient models for various NLP tasks such as OM, NER (Named-Entity Recognition), Question Answering (QA), and so forth. In this study, the traditional and modern NLP approaches have been evaluated for OM by using a sizable corpus belonging to a large private company containing about 76,000 comments in Turkish: SVM with a bag of n-grams, and two chosen pre-trained models, multilingual universal sentence encoder (MUSE) and bidirectional encoder representations from transformers (BERT). The MUSE model is a multilingual model that supports 16 languages, including Turkish, and it is based on convolutional neural networks. The BERT is a monolingual model in our case and transformers-based neural networks. It uses a masked language model and next sentence prediction tasks that allow the bidirectional training of the transformers. During the training phase of the architecture, pre-processing operations such as morphological parsing, stemming, and spelling correction was not used since the experiments showed that their contribution to the model performance was found insignificant even though Turkish is a highly agglutinative and inflective language. The results show that usage of deep learning methods with pre-trained models and fine-tuning achieve about 11% improvement over SVM for OM. The BERT model achieved around 94% prediction accuracy while the MUSE model achieved around 88% and SVM did around 83%. The MUSE multilingual model shows better results than SVM, but it still performs worse than the monolingual BERT model.

Keywords: BERT, MUSE, opinion mining, pretrained language model, SVM, Turkish

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Authors: Maryam Zarra-Nezhad, Ali Moazami-Goodarzi, Joona Muotka, Nina Sajaniemi

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This study examines the extent to which the impact of a universal intervention program, i.e., POMPedaSens, on children’s early social-emotional learning (SEL) is different depending on early childhood education (ECE) teaches stress at work. The POMPedaSens program aims to promote children’s (5–6-year-olds) SEL by supporting ECE teachers’ engagement and emotional availability. The intervention effectiveness has been monitored using an 8-month randomized controlled trial design with an intervention (IG; 26 teachers and 195 children) and a waiting control group (CG; 36 teachers and 198 children) that provided the data before and after the program implementation. The ECE teachers in the IG are trained to implement the intervention program in their early childhood education and care groups. Latent change score analysis suggests that the program increases children’s prosocial behavior in the IG when teachers show a low level of stress. No significant results were found for the IG regarding a change in antisocial behavior. However, when teachers showed a high level of stress, an increase in prosocial behavior and a decrease in antisocial behavior were only found for children in the CG. The results suggest a promising application of the POMPedaSens program for promoting prosocial behavior in early childhood when teachers have low stress. The intervention will likely need a longer time to display the moderating effect of ECE teachers’ well-being on children’s antisocial behavior change.

Keywords: early childhood, social-emotional learning, universal intervention program, professional development, teachers' stress

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Authors: M. Hossain, H. P. Zhu, A. B. Yu

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This paper presents a numerical investigation of regime transition of flow of ellipsoidal particles and a comparison with that of spherical particle assembly. Particle assemblies constituting spherical and ellipsoidal particle of 2.5:1 aspect ratio are examined at separate instances in similar flow conditions in a shear cell model that is numerically developed based on the discrete element method. Correlations among elastically scaled stress, kinetically scaled stress, coordination number and volume fraction are investigated, and show important similarities and differences for the spherical and ellipsoidal particle assemblies. In particular, volume fractions at points of regime transition are identified for both types of particles. It is found that compared with spherical particle assembly, ellipsoidal particle assembly has higher volume fraction for the quasistatic to intermediate regime transition and lower volume fraction for the intermediate to inertial regime transition. Finally, the relationship between coordination number and volume fraction shows strikingly distinct features for the two cases, suggesting that different from spherical particles, the effect of the shear rate on the coordination number is not significant for ellipsoidal particles. This work provides a glimpse of currently running work on one of the most attractive scopes of research in this field and has a wide prospect in understanding rheology of more complex shaped particles in light of the strong basis of simpler spherical particle rheology.

Keywords: DEM, granular rheology, non-spherical particles, regime transition

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Authors: Timur S. Zaripov, Artur K. Gilfanov, Sergei S. Sazhin, Steven M. Begg, Morgan R. Heikal

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The calculation of the concentration of inertial droplets in complex flows is encountered in the modelling of numerous engineering and environmental phenomena; for example, fuel droplets in internal combustion engines and airborne pollutant particles. The results of recent research, focused on the development of methods for calculating concentration and their implementation in the commercial CFD code, ANSYS Fluent, is presented here. The study is motivated by the investigation of the mixture preparation processes in internal combustion engines with direct injection of fuel sprays. Two methods are used in our analysis; the Fully Lagrangian method (also known as the Osiptsov method) and the Eulerian approach. The Osiptsov method predicts droplet concentrations along path lines by solving the equations for the components of the Jacobian of the Eulerian-Lagrangian transformation. This method significantly decreases the computational requirements as it does not require counting of large numbers of tracked droplets as in the case of the conventional Lagrangian approach. In the Eulerian approach the average droplet velocity is expressed as a function of the carrier phase velocity as an expansion over the droplet response time and transport equation can be solved in the Eulerian form. The advantage of the method is that droplet velocity can be found without solving additional partial differential equations for the droplet velocity field. The predictions from the two approaches were compared in the analysis of the problem of a dilute gas-droplet flow around an infinitely long, circular cylinder. The concentrations of inertial droplets, with Stokes numbers of 0.05, 0.1, 0.2, in steady-state and transient laminar flow conditions, were determined at various Reynolds numbers. In the steady-state case, flows with Reynolds numbers of 1, 10, and 100 were investigated. It has been shown that the results predicted using both methods are almost identical at small Reynolds and Stokes numbers. For larger values of these numbers (Stokes — 0.1, 0.2; Reynolds — 10, 100) the Eulerian approach predicted a wider spread in concentration in the perturbations caused by the cylinder that can be attributed to the averaged droplet velocity field. The transient droplet flow case was investigated for a Reynolds number of 200. Both methods predicted a high droplet concentration in the zones of high strain rate and low concentrations in zones of high vorticity. The maxima of droplet concentration predicted by the Osiptsov method was up to two orders of magnitude greater than that predicted by the Eulerian method; a significant variation for an approach widely used in engineering applications. Based on the results of these comparisons, the Osiptsov method has resulted in a more precise description of the local properties of the inertial droplet flow. The method has been applied to the analysis of the results of experimental observations of a liquid gasoline spray at representative fuel injection pressure conditions. The preliminary results show good qualitative agreement between the predictions of the model and experimental data.

Keywords: internal combustion engines, Eulerian approach, fully Lagrangian approach, gasoline fuel sprays, droplets and particle concentrations

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Authors: S. Dikmen Kucuk, A. Tozluoglu, Y. Guner

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In recent years, petroleum-based polymers began to be limited due to effects on human and environmental point of view in many countries. Thus, organic-based biodegradable materials have attracted much interest in the composite industry because of environmental concerns. As a result of this, it has been asked that inorganic and petroleum-based materials should be reduced and altered with biodegradable materials. In this point, in this study, it is aimed to investigate the potential of use of TEMPO (2,2,6,6- tetramethylpiperidine 1-oxyl)-mediated oxidation nano-fibrillated cellulose instead of EPDM (ethylene-propylene-diene monomer) rubber, which is a petroleum-based material. Thus, the exchange of petroleum-based EPDM rubber with organic based cellulose nanofibers, which are environmentally friendly (green) and biodegradable, will be realized. The effect of tempo-oxidized cellulose nanofibers (TCNF) instead of EPDM rubber was analyzed by rheological, mechanical, chemical, thermal and aging analyses. The aged surfaces were visually scrutinized and surface morphological changes were examined via scanning electron microscopy (SEM). The results obtained showed that TEMPO oxidation nano-fibrillated cellulose can be used at an amount of 1.0 and 2.2 phr resulting the values stay within tolerance according to customer standard and without any chemical degradation, crack, colour change or staining.

Keywords: EPDM, cellulose, green materials, nanofibrillated cellulose, TCNF, tempo-oxidized nanofiber

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Authors: Saksham

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Concrete's versatility and affordability make it a highly competitive building material capable of meeting diverse requirements. However, the increasing demands placed on structures and the need for enhanced durability and performance have driven the development of distinct cementitious materials and concrete composites. One significant aspect of this advancement is the utilization of waste materials from industries, such as fly ash, to improve concrete's properties. Fly ash, a byproduct of coal combustion can enhance concrete's strength and durability while reducing environmental impact. Additionally, steel fibers can enhance concrete's toughness and crack resistance, contributing to improved structural performance. The experimental study aims to optimize the proportion of ingredients in M30-grade concrete, incorporating fly ash and steel fibers. By varying fly ash content (10% to 30%) and steel fiber dosage (0% to 1.5%), the research seeks to determine the optimal combination for achieving the desired compressive strength. Two sets of experiments are conducted: one focusing on varying fly ash content while keeping steel fiber dosage constant, and the other focusing on varying steel fiber dosage while keeping other parameters fixed. Through systematic testing, molding, curing, and evaluation according to specified standards, the research aims to analyze the impact of fly ash and steel fibers on concrete's compressive strength. The findings have the potential to inform engineers about optimized concrete mix designs that balance performance, cost-effectiveness, and sustainability, advancing toward more resilient and environmentally friendly building practices.

Keywords: concrete, sustainability, durability, compressive strength

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Authors: Mamata Mohanty, J. T. Shahu

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The in-situ deep mixing is an effective ground improvement technique which involves columnar inclusion into soft ground to increase its bearing capacity and reduce settlement. The first part of the study presents the results of unconfined compression on cement-admixed clay prepared at different cement content and subjected to varying curing periods. It is found that cement content is a prime factor controlling the strength of the cement-admixed clay. Besides cement content, curing period is important parameter that adds to the strength of cement-admixed clay. Increase in cement content leads to significant increase in Unconfined Compressive Strength (UCS) values especially at cement contents greater than 8%. The second part of the study investigated the bearing capacity of the clay ground improved by a group of end-bearing column using model tests under plain-strain condition. This study mainly focus to examine the effect of cement contents on the ultimate bearing capacity and failure stress of the improved clay ground. The study shows that the bearing capacity of the improved ground increases significantly with increase in cement contents of the soil-cement columns. A considerable increase in the stiffness of the model ground and failure stress was observed with increase in cement contents.

Keywords: bearing capacity, cement content, curing time, unconfined compressive strength, undrained shear strength

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Authors: Sophie Whittle

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Prior to present day, English syntax historically exhibited an inconsistent verb-second (V2) rule, which saw the verb move to the second position in the sentence following the fronting of a type of phrase. There was a high amount of variation throughout the history of English with regard to the ordering of subject and verb, and many explanations attempting to account for this variation have been documented in previous literature. However, these attempts have been contradictory, with many accounts positing the effect of previous syntactic changes as the main motivations behind the decline of V2. For instance, morphosyntactic changes, such as the loss of clitics and the loss of empty expletives, have been loosely connected to changes in frequency for the loss of V2. The questions surrounding the development of non-V2 in English have, therefore, yet to be answered. The current paper aims to bring together a number of explanations from different linguistic fields to determine the factors driving the changes in English V2. Using historical corpus-based methods, the study analyses both quantitatively and qualitatively the changes in frequency for the history of V2 in the Old, Middle, and Modern English periods to account for the variation in a range of sentential environments. These methods delve into the study of information structure, prosody and language contact to explain variation within different contexts. The analysis concludes that these factors, in addition to changes within the syntax, are responsible for the position of verb movement. The loss of V2 serves as an exemplar study within the field of historical linguistics, which combines a number of factors in explaining language change in general.

Keywords: corpora, English, language change, mixed-methods, syntax, verb-second

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Authors: T. H. Huang, C. L. Fern, Y. K. Tseng

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The design and reliability of solar photovoltaic modules are crucial to the development of solar energy, and efforts are still being made to extend the life of photovoltaic modules to improve their efficiency because natural aging is time-consuming and does not provide manufacturers and investors with timely information, accelerated aging is currently the best way to estimate the life of photovoltaic modules. Bifacial solar cells not only absorb light from the front side but also absorb light reflected from the ground on the back side, surpassing the performance of single-sided solar cells. Due to the asymmetry of the two sides of the light, in addition to the difference in photovoltaic conversion efficiency, there will also be differences in heat distribution, which will affect the electrical properties and material structure of the bifacial solar cell itself. In this study, there are two types of experimental samples: packaged and unpackaged and then irradiated with UVC light sources and halogen lamps for accelerated aging, as well as a control group without aging. After two weeks of accelerated aging, the bifacial solar cells were visual observation, and infrared thermal images were taken; then, the samples were subjected to IV measurement, and samples were taken for SEM, Raman, and XRD analyses in order to identify the defects that lead to failure and chemical changes, as well as to analyze the reasons for the degradation of their characteristics. From the results of the analysis, it is found that aging will cause carbonization of the polymer material on the surface of bifacial solar cells, and the crystal structure will be affected.

Keywords: bifacial solar cell, accelerated aging, temperature, characterization, electrical measurement

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Authors: Liliana Gomez Cardona, Mary McComber, Kristyn Brown, Arlene Laliberté, Outi Linnaranta

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The history of colonialism and more contemporary political issues have resulted in the exposure of Kanien'kehá:ka: non (Kanien'kehá:ka of Kahnawake) to challenging and even traumatic experiences. Colonization, religious missions, residential schools as well as economic and political marginalization are the factors that have challenged the wellbeing and mental health of these populations. In psychiatry, screening for mental illness is often done using questionnaires with which the patient is expected to respond to how often he/she has certain symptoms. However, the Indigenous view of mental wellbeing may not fit well with this approach. Moreover, biomedical treatments do not always meet the needs of Indigenous people because they do not understand the culture and traditional healing methods that persist in many communities. Assess whether the questionnaires used to measure symptoms, commonly used in psychiatry are appropriate and culturally safe for the Mohawk in Quebec. Identify the most appropriate tool to assess and promote wellbeing and follow the process necessary to improve its cultural sensitivity and safety for the Mohawk population. Qualitative, collaborative, and participatory action research project which respects First Nations protocols and the principles of ownership, control, access, and possession (OCAP). Data collection based on five focus groups with stakeholders working with these populations and members of Indigenous communities. Thematic analysis of the data collected and emerging through an advisory group that led a revision of the content, use, and cultural and conceptual relevance of the instruments. The questionnaires measuring psychiatric symptoms face significant limitations in the local indigenous context. We present the factors that make these tools not relevant among Mohawks. Although the scale called Growth and Empowerment Measure (GEM) was originally developed among Indigenous in Australia, the Mohawk in Quebec found that this tool comprehends critical aspects of their mental health and wellbeing more respectfully and accurately than questionnaires focused on measuring symptoms. We document the process of cultural adaptation of this tool which was supported by community members to create a culturally safe tool that helps in growth and empowerment. The cultural adaptation of the GEM provides valuable information about the factors affecting wellbeing and contributes to mental health promotion. This process improves mental health services by giving health care providers useful information about the Mohawk population and their clients. We believe that integrating this tool in interventions can help create a bridge to improve communication between the Indigenous cultural perspective of the patient and the biomedical view of health care providers. Further work is needed to confirm the clinical utility of this tool in psychological and psychiatric intervention along with social and community services.

Keywords: cultural adaptation, cultural safety, empowerment, Mohawks, mental health, Quebec

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Authors: Priyajeet Kaur Kaleka

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Introduction: A dentist is often the first responder in the battle for a patient’s healthy body and maybe the first health professional to observe signs of child abuse, be it physical, emotional, and/or sexual mistreatment. Therefore, it is an ethical responsibility for the dental clinician to detect and report suspected cases of child abuse and neglect (CAN). The main reasons for not reporting suspected cases of CAN, with special emphasis on the third: 1) Uncertainty of the diagnosis, 2) Lack of knowledge of the reporting procedure, and 3) Child abuse and neglect somewhat remained the subject of ignorance among dental professionals because of a lack of advance clinical training. Given these epidemic proportions, there is a scope of further research about dental school curriculum design. Purpose: This study aimed to assess the knowledge and attitude of dentists in Canada regarding signs and symptoms of child abuse and neglect (CAN), reporting procedures, and whether educational strategies followed by dental schools address this sensitive issue. In pursuit of that aim, this abstract summarizes the evidence related to this question. Materials and Methods: Data was collected through a specially designed questionnaire adapted and modified from the author’s previous cross-sectional study on (CAN), which was conducted in Pune, India, in 2016 and is available on the database of PubMed. Design: A random sample was drawn from the targeted population of registered dentists and dental students in Canada regarding their knowledge, professional responsibilities, and behavior concerning child abuse. Questionnaire data were distributed to 200 members. Out of which, a total number of 157 subjects were in the final sample for statistical analysis, yielding response of 78.5%. Results: Despite having theoretical information on signs and symptoms, 55% of the participants indicated they are not confident to detect child physical abuse cases. 90% of respondents believed that recognition and handling the CAN cases should be a part of undergraduate training. Only 4.5% of the participants have correctly identified all signs of abuse due to inadequate formal training in dental schools and workplaces. Although nearly 96.3% agreed that it is a dentist’s legal responsibility to report CAN, only a small percentage of the participants reported an abuse case in the past. While 72% stated that the most common factor that might prevent a dentist from reporting a case was doubt over the diagnosis. Conclusion: The goal is to motivate dental schools to deal with this critical issue and provide their students with consummate training to strengthen their capability to care for and protect children. The educational institutions should make efforts to spread awareness among dental students regarding the management and tackling of CAN. Clinical Significance: There should be modifications in the dental school curriculum focusing on problem-based learning models to assist graduates to fulfill their legal and professional responsibilities. CAN literacy should be incorporated into the dental curriculum, which will eventually benefit future dentists to break this intergenerational cycle of violence.

Keywords: abuse, child abuse and neglect, dentist knowledge, dental school curriculum, problem-based learning

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