Search results for: index factor
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 8382

Search results for: index factor

2532 Advancements in Dielectric Materials: A Comprehensive Study on Properties, Synthesis, and Applications

Authors: M. Mesrar, T. Lamcharfi, Nor-S. Echatoui, F. Abdi

Abstract:

The solid-state reaction method was used to synthesize ferroelectric systems with lead-free properties, specifically (1-x-y)(Na₀.₅Bi₀.₅)TiO₃-xBaTiO₃-y(K₀.₅ Bi₀.₅)TiO₃. To achieve a pure perovskite phase, the optimal calcination temperature was determined to be 1000°C for 4 hours. X-ray diffraction (XRD) analysis identified the presence of the morphotropic phase boundary (MPB) in the (1-x-y)NBT xBT-yKBT ceramics for specific molar compositions, namely (0.95NBT-0.05BT, 0.84NBT-0.16KBT, and 0.79NBT-0.05BT-0.16KBT). To enhance densification, the sintering temperature was set at 1100°C for 4 hours. Scanning electron microscopy (SEM) images exhibited homogeneous distribution and dense packing of the grains in the ceramics, indicating a uniform microstructure. These materials exhibited favorable characteristics, including high dielectric permittivity, low dielectric loss, and diffused phase transition behavior. The ceramics composed of 0.79NBT-0.05BT-0.16KBT exhibited the highest piezoelectric constant (d33=148 pC/N) and electromechanical coupling factor (kp = 0.292) among all compositions studied. This enhancement in piezoelectric properties can be attributed to the presence of the morphotropic phase boundary (MPB) in the material. This study presents a comprehensive approach to improving the performance of lead-free ferroelectric systems of composition 0.79(Na₀.₅Bi₀.₅)Ti O₃-0.05BaTiO₃-0.16(K₀.₅Bi₀.₅)TiO₃.

Keywords: solid-state method, (1-x-y)NBT-xBT-yKBT, morphotropic phase boundary, Raman spectroscopy, dielectric properties

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2531 Characterization of Some Bread Wheat Genotypes for Drought Tolerance Using Molecular Markers

Authors: Begüm Terzi, Özlem Ateş Sönmezoğlu, Ahmet Yildirim

Abstract:

Drought is the most important factor that limiting the production and productivity of wheat in the world. The yield of wheat, which is one of the most important crop in the world, reduced depend on drought. Researches to minimize effects of drought are one of the most important about breeding of drought resistant varieties. In recent years, benefiting from the drought resistance wild species and rapid advances in molecular biology studies, researches about drought have been accelerated and number of studies were made on molecular plant breeding which included the molecular mechanisms related to drought resistance. The aim of the present study was characterization of some bread wheat lines for drought tolerance which commonly cultivated in different location of Turkey. In this study, registered 9 bread wheat varieties which on the physiological tests about drought tolerance and 10 bread wheat line has been developed by Transitional Zone Agricultural Research Institute were used. SSR, STS, RAPD and SNP markers that associated with drought tolerance were used. The polymorphisms of the markers were determined by screening of two control varieties. For these purpose 40 molecular markers were used and 12 markers of them were polymorphic among the drought tolerance and the drought sensitive varieties. Control varieties were screened using polymorphic markers. All the DNAs on the genotypes will be searched for the presence of QTLs mapped to different chromosomes. Result of the research, the studied genotypes will be grouped according to drought tolerance and will be detected drought tolerance varieties by molecular markers. In addition, the results will be compared also with physiological tests. The drought tolerant wheat genotypes may be used in breeding studies related to drought stress.

Keywords: bread wheat, drought, molecular marker, Triticum aestivum

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2530 Risk Factors for Postoperative Fever in Patients Undergoing Lumbar Fusion

Authors: Bang Haeyong

Abstract:

Purpose: The objectives of this study were to determine the prevalence, incidence, and risk factors for postoperative fever after lumbar fusion. Methods: This study was a retrospective chart review of 291 patients who underwent lumbar fusion between March 2015 and February 2016 at the Asan Medical Center. Information was extracted from electronic medical records. Postoperative fever was measured at Tmax > 37.7 ℃ and Tmax > 38.3 ℃. The presence of postoperative fever, blood culture, urinary excretion, and/or chest x-ray were evaluated. Patients were evaluated for infection after lumbar fusion. Results: We found 222 patients (76.3%) had a postoperative temperature of 37.7 ℃, and 162 patients (55.7%) had a postoperative temperature of 38.3 ℃ or higher. The percentage of febrile patients trended down following the mean 1.8days (from the first postoperative day to seventh postoperative day). Infection rate was 9 patients (3.1%), respiratory virus (1.7%), urinary tract infection (0.3%), phlebitis (0.3%), and surgical site infection (1.4%). There was no correlation between Tmax > 37.7℃ or Tmax > 38.3℃, and timing of fever, positive blood or urine cultures, pneumonia, or surgical site infection. Risk factors for increased postoperative fever following surgery were confirmed to be delay of defecation (OR=1.37, p=.046), and shorten of remove drainage (OR=0.66, p=.037). Conclusions: The incidence of fever was 76.3% after lumbar fusion and the drainage time was faster in the case of fever. It was thought that the bleeding was absorbed at the operation site and fever occurred. The prevalence of febrile septicemia was higher in patients with long bowel movements before surgery than after surgery. Clinical symptoms should be considered because postoperative fever cannot be determined by fever alone because fever and infection are not significant.

Keywords: lumbar surgery, fever, postoperative, risk factor

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2529 Expert-Based Validated Measures for Improving Quality Healthcare Services Utilization among Elderly Persons: A Cross-Section Survey

Authors: Uchenna Cosmas Ugwu, Osmond Chukwuemeka Ene

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Globally, older adults are considered the most vulnerable groups to age-related diseases including diabetes mellitus, obesity, cardiovascular diseases, cancer and osteoporosis. With improved access to quality healthcare services, these complications can be prevented and the incidence rates reduced to the least occurrence. The aim of this study is to validate appropriate measures for improving quality healthcare services utilization among elderly persons in Nigeria and also to determine the significant association within demographic variables. A cross-sectional survey research design was adopted. Using a convenient sampling technique, a total of 400 experts (150 registered nurses and 250 public health professionals) with minimum of doctoral degree qualification were sampled and studied. A structured instrument titled “Expert-Based Healthcare Services Utilization Questionnaire (EBHSUQ) with .83 reliability index was used for data collection. All the statistical data analysis was completed using frequency counts, percentage scores and chi-square statistics. The results were significant at p≤0.05. It was found that quality healthcare services utilization by elderly persons in Nigeria would be improved if the services are: available (83%), affordable (82%), accessible (79%), suitable (77%), acceptable (77%), continuous (75%) and stress-free (75%). Statistically, significant association existed on quality healthcare services utilization with gender (p=.03<.05) and age (p=.01<.05) while none was observed on work experience (p=.23>.05), marital status (p=.11>.05) and employment category (p=.09>.05). To improve quality healthcare services utilization for elderly persons in Nigeria, the adoption of appropriate measures by Nigerian government and professionals in healthcare sectors are paramount. Therefore, there is need for collaborative efforts by the Nigerian government and healthcare professionals geared towards educating the general public through mass sensitization, awareness campaign, conferences, seminars and workshops for the importance of accessing healthcare services.

Keywords: elderly persons, healthcare services, cross-sectional survey research design, utilization.

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2528 Association of Laterality and Sports Specific Rotational Preference with Number of Injuries in Artistic Gymnasts

Authors: Teja Joshi

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Laterality has shown to play a role in performance as well as injuries especially in unilateral sports disciplines. Uniquely, Artistic Gymnastics involves combination of unilateral, bilateral and complex multi-planer elements as well as gymnastics specific rotational preference. Therefore, this study was conducted to explore if any such preferences are associated with number of injuries in artistic gymnasts. To explore the association between lateral preferences, rotational preferences and injuries incidence in artistic gymnastics. Artistic gymnasts above 16 years of age, were invited to participate in an online survey. The survey included consent, lateral preference inventory, injury data collection according to anatomical locations and rotational preference for selected gymnastics elements performed on the floor exercise. SPSS version 24 was used to analyse Non-parametric data using Kruskal-Wallis (K- independent test) test. Multiple regression was performed to identify the predictor for injuries and their side in gymnasts. Total number of injuries per gymnast was associated with handedness (p value-0.049) and no significant association was noted for footdness (p value-0.207), eyedness (p value-0.491) and eardness (p value-0.798). Additionally, rotational preferences did not influence number of injuries (p value-0.521). In multiple regression, eyedness was identified as a predicting factor to determine the number of injuries. Rotational preferences were neither determined as a national strategy nor a product of lateral preference. Dominant hand had higher number of injuries in artistic gymnasts. Rotational preference is independent of laterality, number of injuries and nationality.

Keywords: sports injury, rotational preference, gymnastics, handedness

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2527 Comparison of Multivariate Adaptive Regression Splines and Random Forest Regression in Predicting Forced Expiratory Volume in One Second

Authors: P. V. Pramila , V. Mahesh

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Pulmonary Function Tests are important non-invasive diagnostic tests to assess respiratory impairments and provides quantifiable measures of lung function. Spirometry is the most frequently used measure of lung function and plays an essential role in the diagnosis and management of pulmonary diseases. However, the test requires considerable patient effort and cooperation, markedly related to the age of patients esulting in incomplete data sets. This paper presents, a nonlinear model built using Multivariate adaptive regression splines and Random forest regression model to predict the missing spirometric features. Random forest based feature selection is used to enhance both the generalization capability and the model interpretability. In the present study, flow-volume data are recorded for N= 198 subjects. The ranked order of feature importance index calculated by the random forests model shows that the spirometric features FVC, FEF 25, PEF,FEF 25-75, FEF50, and the demographic parameter height are the important descriptors. A comparison of performance assessment of both models prove that, the prediction ability of MARS with the `top two ranked features namely the FVC and FEF 25 is higher, yielding a model fit of R2= 0.96 and R2= 0.99 for normal and abnormal subjects. The Root Mean Square Error analysis of the RF model and the MARS model also shows that the latter is capable of predicting the missing values of FEV1 with a notably lower error value of 0.0191 (normal subjects) and 0.0106 (abnormal subjects). It is concluded that combining feature selection with a prediction model provides a minimum subset of predominant features to train the model, yielding better prediction performance. This analysis can assist clinicians with a intelligence support system in the medical diagnosis and improvement of clinical care.

Keywords: FEV, multivariate adaptive regression splines pulmonary function test, random forest

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2526 Effects of Screen Time on Children from a Systems Engineering Perspective

Authors: Misagh Faezipour

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This paper explores the effects of screen time on children from a systems engineering perspective. We reviewed literature from several related works on the effects of screen time on children to explore all factors and interrelationships that would impact children that are subjected to using long screen times. Factors such as kids' age, parent attitudes, parent screen time influence, amount of time kids spend with technology, psychosocial and physical health outcomes, reduced mental imagery, problem-solving and adaptive thinking skills, obesity, unhealthy diet, depressive symptoms, health problems, disruption in sleep behavior, decrease in physical activities, problematic relationship with mothers, language, social, emotional delays, are examples of some factors that could be either a cause or effect of screen time. A systems engineering perspective is used to explore all the factors and factor relationships that were discovered through literature. A causal model is used to illustrate a graphical representation of these factors and their relationships. Through the causal model, the factors with the highest impacts can be realized. Future work would be to develop a system dynamics model to view the dynamic behavior of the relationships and observe the impact of changes in different factors in the model. The different changes on the input of the model, such as a healthier diet or obesity rate, would depict the effect of the screen time in the model and portray the effect on the children’s health and other factors that are important, which also works as a decision support tool.

Keywords: children, causal model, screen time, systems engineering, system dynamics

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2525 Variability of the Snowline Altitude at Different Region in the Eastern Tibetan Plateau in Recent 20 Years

Authors: Zhen Li, Chang Liu, Ping Zhang

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These Glaciers are thought of as natural water reservoirs and are of vital importance to hydrological models and industrial production, and glacial changes act as significant indicators of climate change. The glacier snowline can be used as an indicator of the equilibrium line, which may be a key parameter to study the effect of climate change on glaciers. Using Google Earth Engine, we select optical satellite imageries and implement the Otsu thresholding method on a near-infrared band to detect snowline altitudes (SLAs) of 26 glaciers in three regions of the eastern Tibetan Plateau. Three different study regions in the eastern Tibetan Plateau have different climate regimes, which are Sepu Kangri (SK, maritime glacier), Bu’Gyai Kangri (BK, continental glacier) and west of Qiajajima (WQ, continental glacier), along a latitudinal transect from south to north. We analyzed the effects of climatic factors on the SLA changes from 1995 to 2016. SLAs are fluctuating upward, and the rising values are 100 m, 60 m, and 34 m from south to north during the 22 years. We also observed that the climatic factor that affects the variability of SLA gradually changes from precipitation to temperature from south to north. The northern continental glaciers are mainly affected by temperature, and the southern maritime glaciers affected by precipitation. Owing to the influence of primary climatic factors, continental glaciers are found to have higher SLAs on the south slope, while maritime glaciers have higher SLAs on the north slope.

Keywords: climate change, glacier, snowline altitude, tibetan plateau

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2524 Organizational Climate of Silence and Job Performance: Examining the Mediatory and Moderating Role of Work Engagement and Supervisor Support among Frontline Nurses

Authors: Sabina Ampon-Wireko

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Purpose: The study explores the influence of the organizational climate of silence on job performance through the mediating effects of work engagement (WE). Further, the degree to which supervisor support (SS) and work engagement moderate job performance are examined. Method: Using a questionnaire, the study collected 565 valid responses from frontline nurses in Ghana. The hierarchical regression technique was employed in estimating the relationship between the variables. Findings: The results showed a significant negative influence of top managers' and supervisors' attitudes to silence on both contextual and task performance. Communication opportunities, however, revealed positive and significant effects on contextual and task performance. Work engagement had no role in mediating top managers' and supervisors’ attitudes toward silence, communication opportunities, and task performance. Supervisor support acted as a moderating factor in the relationship between job engagement and task performance. In contrast, despite the direct positive relationship between supervisor support and contextual performance, it failed to moderate the relationship between work engagement and contextual performance. Practical implications: The study's findings demonstrate the need for health managers and supervisors to become more conscious of silence. The findings offer diverse recommendations for encouraging the sharing of relevant ideas, facts, and opinions within the health sector.

Keywords: organizational climate of silence, job performance, work engagement, supervisor support, frontline nurses

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2523 The Impact of Perspective Taking and Gender Differences on the Encouragement of Social Competence for the Next Generation: The Evidence From Chinese Parents

Authors: Yi Huang

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Background: For the development of children, it is important for parents to encourage children not only on academic competence but also on children’s social competence. In the western cultural context, parents emphasize more heavily on female children’s social-behavioral development. However, whether the conclusion is correct in eastern culture and whether the parent’s gender affects such an emphasis remains unclear. And, more valuably, from the perspective of intervention, except for the nature factors - child’s gender and parent’s gender, it is also worth to probe whether the improvable factors, such as parent’s perspective taking, influence parent’s emphasis on child’s social competence. Aim: This study was aimed to investigate the impact of parent’s gender, child’s gender, and parent’s perspective-taking on parent’s attitudes of encouragement of the child’s social competence under the Chinese cultural context. Method: 461 Chinese parents whose children were in the first year of middle school during the research time participated in this study. Among all participants, there were 155 fathers and 306 mothers. The research adopted the self-report of perspective-taking, which is the sub-scale of the Interpersonal Reactivity Index and the self-report of the encouragement on a child’s social communication, which is the sub-scale of the Chinese version of The Children Rearing Practice Report. In this study, 291 parents reported regarding male children, and 170 parents reported regarding female children. Results: Contrary to the traditional western theory, which usually suggests parent puts more attention on social development and competence to girl the instead of the boy, in the Chinese context, parent emphasizes social competence more on the male child. Analogically, in China, compared to mother, father underscores the child’s social competence more heavily. By constructing the hierarchical regression model, the result indicated that after controlling the variables of the gender of child and the gender of parent, parent’s perspective-taking still explains for the variance of parent’s encouragement on child’s social competence, which means, parent’s perspective-taking predicts parent’s encouragement on child’s social competence after excluding the impact of the gender of parent and child. Conclusion: For Chinese parents, the ability of perspective-taking is beneficial to enhance their awareness of encouraging children’s social competence.

Keywords: parent; child, gender differences, perspective-taking, social development

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2522 Anti-Melanogenesis and Anti-Inflammatory Effects of Opuntia humifusa

Authors: Yonghwa Lee, Yoon Suk Kim, Yongsub Yi

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This study was to confirm the effects of anti-melanogenesis and anti-inflammatory effects from Opuntia humifusa fruit and stem extracts. A potent anti-oxidant activity was shown from the leaf extract at IC50 value of 38.33±1.07 μg/mL and fruit extract at IC50 value of 40.23±2.21 μg/mL by 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay. Also, phenolic contents were confirmed total phenolic assay by high performance liquid chromatography (HPLC). Fraction of taxifolin from leaf extract was identified using HPLC and gas chromatography/mass spectrometry. The extracts of Opuntia humifusa fruit and stem were confirmed about toxicity effect in B16 F1 by cell viability. Melanin contents were decreased. Opuntia humifusa fruit and stem extracts had a positive effect of melanin synthesis inhibition for skin whitening. In investigating the anti-inflammatory activities of Opuntia humifusa, the results of cell viability indicated that taxifolin did not show cytotoxicity on RAW264.7 cells at 500 μM of concentration. The results show that taxifolin inhibited lipopolysaccharide (LPS)-induced production of Nitrite oxide (NO). In addition, taxifolin indicated the inhibition of lipopolysaccharide (LPS)-induced tumor necrosis factor (TNF) -α and interleukin (IL) -6 productions by cytokine assay and cyclooxygenase (COX)-2 expression by western blot analysis, meaning that taxifolin had a significant anti-inflammatory effect. Our results suggested that taxifolin from Opuntia humifusa has anti-melanogenesis and anti-inflammatory activities.

Keywords: anti-melanogenesis, anti-inflammatory, Opuntia humifusa, taxifolin

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2521 Dancing in Bullets and in Brokenness: Metaphor in Terracotta on Canvas

Authors: Jonathan Okewu

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Socio-economic occurrences and developments in any society is usually a thing of concern especially when this is been jeopardised as a result of insecurity of all sorts. There are numerous channels that such issues are brought to the fore for attention. Among this channels are the art media and more precisely the ceramic art media. Renown ceramic artists in Nigeria have taken to the medium of expression (clay) to contribute to succinct issues as it affects the society. This study takes advantage of a unique form of ceramic press moulding termed clay palm press. This uncommon production technique has been developed in this study to interrogate socio-economic insecurity in the form of ceramic art titled; “dancing in bullets and in brokenness”. This work was made possible through a ceramic medium that has been termed “terracotta on canvas”. Extensive studio practice was carried out to generate the terracotta forms for this study. Findings from this study indicates that the medium and mode of execution of the art work shows a unique side of working with clay that negates tactile or three dimensionality of inured ceramic practice. Additionally, the process of clay palm press in this study indicates that it could be therapeutical against medical conditions of muscles of the palm. This is because the process tightens and develops the muscles of the palm further. Dancing in bullets and in brokenness as portrayed through the medium of terracotta on canvas that social and security challenges are not a limiting factor to a resolute Nigerian, despite all, the strong will of Nigerians keeps persisting and overcoming challenges.

Keywords: canvas, dancing in bullets and in brokenness, metaphor, terracotta, palm press

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2520 Caught in the Crossfire : Natural Resources, Energy Transition, and Conflict in the Democratic Republic of Congo

Authors: Koami West Togbetse

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The global shift towards clean and sustainable energy sources, known as the energy transition, is compelling numerous countries to transition from polluting energy systems to cleaner alternatives, commonly referred to as green energies. In this context, cobalt holds significant importance as a crucial mineral in facilitating this energy transition due to its pivotal role in electric batteries. Considering the Democratic Republic of Congo’s reputation for political instability and its position as the largest producer of cobalt, possessing over 50% of the world’s reserves, we have assessed the potential conflicts that may arise as a result of the rapid increase in cobalt demand. The results show that cobalt does not appear to be a determinant contributing to all past conflicts over the study period in the Democratic Republic of Congo (DRC). Gold, on the other hand, stands out as one of the coveted metals for rebel groups engaged in rampant exploitation, increasing the likelihood of conflicts occurring. However, a more in-depth analysis reveals a shift in the relationship between cobalt production and conflict events around 2006. Prior to 2006, increased cobalt production was significantly associated with a reduction in conflict events. However, after 2006, this relationship became positive, indicating that higher cobalt production is now linked to a slight increase in conflict events. This suggests a change in the dynamics affecting conflicts related to cobalt production before and after 2006. According to our predictive model, cobalt has the potential to emerge increasingly as a contributing factor, just like gold.

Keywords: conflicts, natural resources, energy transition, geopolitics

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2519 Use of Front-Face Fluorescence Spectroscopy and Multiway Analysis for the Prediction of Olive Oil Quality Features

Authors: Omar Dib, Rita Yaacoub, Luc Eveleigh, Nathalie Locquet, Hussein Dib, Ali Bassal, Christophe B. Y. Cordella

Abstract:

The potential of front-face fluorescence coupled with chemometric techniques, namely parallel factor analysis (PARAFAC) and multiple linear regression (MLR) as a rapid analysis tool to characterize Lebanese virgin olive oils was investigated. Fluorescence fingerprints were acquired directly on 102 Lebanese virgin olive oil samples in the range of 280-540 nm in excitation and 280-700 nm in emission. A PARAFAC model with seven components was considered optimal with a residual of 99.64% and core consistency value of 78.65. The model revealed seven main fluorescence profiles in olive oil and was mainly associated with tocopherols, polyphenols, chlorophyllic compounds and oxidation/hydrolysis products. 23 MLR regression models based on PARAFAC scores were generated, the majority of which showed a good correlation coefficient (R > 0.7 for 12 predicted variables), thus satisfactory prediction performances. Acid values, peroxide values, and Delta K had the models with the highest predictions, with R values of 0.89, 0.84 and 0.81 respectively. Among fatty acids, linoleic and oleic acids were also highly predicted with R values of 0.8 and 0.76, respectively. Factors contributing to the model's construction were related to common fluorophores found in olive oil, mainly chlorophyll, polyphenols, and oxidation products. This study demonstrates the interest of front-face fluorescence as a promising tool for quality control of Lebanese virgin olive oils.

Keywords: front-face fluorescence, Lebanese virgin olive oils, multiple Linear regressions, PARAFAC analysis

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2518 Exploring Spin Reorientation Transition and Berry Curvature Driven Anomalous Hall Effect in Quasi-2D vdW Ferromagnet Fe4GeTe2

Authors: Satyabrata Bera, Mintu Mondal

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Two-dimensional (2D) ferromagnetic materials have garnered significant attention due to their potential to host intriguing scientific phenomena such as the anomalous Hall effect, anomalous Nernst effect, and high transport spin polarization. This study focuses on the investigation of air-stable van der Waals(vdW) ferromagnets, FeGeTe₂ (FₙGT with n = 3, 4, and 5). Particular emphasis is placed on the Fe4GeTe2 (F4GT) compound, which exhibits a complex and fascinating magnetic behavior characterized by two distinct transitions: (i) paramagnetic (PM) to ferromagnetic (FM) around T C ∼ 270 K, and (ii) another spins reorientation transition (SRT) at T SRT ∼ 100 K . Scaling analysis of magnetocaloric effect confirms the second-order character of the ferromagnetic transition, while the same analysis at T SRT suggests that SRT is first-order phase transition. Moreover, the F4GT exhibits a large anomalous Hall conductivity (AHC), ∼ 490 S/cm at 2 K . The near-quadratic behavior of the anomalous Hall resistivity with the longitudinal resistivity suggests that a dominant AHC contribution arises from an intrinsic Berry curvature (BC) mechanism. Electronic structure calculations reveal a significant BC resulting from SOC-induced gapped nodal lines around the Fermi level, thereby giving rise to large AHC. Additionally, we reported exceptionally large anomalous Hall angle (≃ 10.6%) and Hall factor (≃ 0.22 V −1 ) values, the largest observed within this vdW family. The findings presented here, provide valuable insights into the fascinating magnetic and transport properties of 2D ferromagnetic materials, in particular, FₙGT family.

Keywords: 2D vdW ferromagnet, spin reorientation transition, anomalous hall effect, berry curvature

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2517 Optimization of Tangential Flow Filtration Process for Purifying DNA Vaccine

Authors: Piyakajornkul T., Noppiboon S., Hochareon L., Kitsubun P.

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Nowadays, DNA vaccines become an interesting subject in the third vaccine generation. The platform of DNA vaccines production has been developed and its downstream process becomes challenging due to the quality of the products in terms of purity and percentage of supercoiled DNA. To overcome these challenges, tangential flow filtration (TFF), which is involved in the purification process, could be used since it provides effective separation of impurity prior to performing further purification steps. However, operating conditions of TFF is varied based on several factors such as sizes of target particle and impurities, a concentration of solution as well as a concentration polarization on the membrane surface. In this study, pVAX1/lacZ was used as a model of TFF optimization in order to prevent a concentration polarization that can lead to the membrane fouling and also minimize a diafiltration volume while maintaining the maximum permeate flux resulting in proper operating times and buffer volume. By using trans membrane pressure (TMP) excursion method, feed flow rates and TMP were varied. The results showed a correlation of permeate flux with TMP where the maximum volume concentration factor reached 2.5 times of the initial volume when feed flow rate and TMP were 7 liters/m²/min and 1 bar, respectively. It was optimal operating conditions before TFF system undergone pressure independent regime. In addition, the diafiltration volume was 14 times of the concentrated volume prior to performing a further anion chromatography process.

Keywords: concentration polarization, DNA vaccines, optimization, permeate flux, pressure dependent, tangential flow filtration (TFF), trans membrane pressure (TMP)

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2516 Dielectric Properties of Thalium Selenide Thin Films at Radio Wave Frequencies

Authors: Onur Potok, Deniz Deger, Kemal Ulutas, Sahin Yakut, Deniz Bozoglu

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Thalium Selenide (TlSe) is used for optoelectronic devices, pressure sensitive detectors, and gamma-ray detectors. The TlSe samples were grown as large single crystals using the Stockbarger-Bridgman method. The thin films, in the form of Al/TlSe/Al, were deposited on the microscope slide in different thicknesses (300-3000 Å) using thermal evaporation technique at 10-5 Torr. The dielectric properties of (TlSe) thin films, capacitance (C) and dielectric loss factor (tanδ), were measured in a frequency range of 10-105 Hz, and temperatures between 213K and 393K via Broadband Dielectric Spectroscopy analyzer. The dielectric constant (ε’) and the dielectric loss (ε’’) of the thin films were derived from measured parameters (C and tanδ). These results showed that the dielectric properties of TlSe thin films are frequency and temperature dependent. The capacitance and the dielectric constant decrease with increasing frequency and decreasing temperature. The dielectric loss of TlSe thin films decreases with increasing frequency, on the other hand, they increase with increasing temperature and increasing thicknesses. There is two relaxation region in the investigated frequency and temperature interval. These regions can be called as low and high-frequency dispersion regions. Low-frequency dispersion region can be attributed to the polarization of the main part of the chain structure of TlSe while high-frequency dispersion region can be attributed to the polarization of side parts of the structure.

Keywords: thin films, thallium selenide, dielectric spectroscopy, binary compounds

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2515 Long-Term Outcomes of Dysphagia in Children with Severe Cerebral Palsy Using Videofluoroscopic Evaluation

Authors: Eun Jae Ko, In Young Sung, Eui Soo Joeng

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Oropharyngeal dysphagia is prevalent in children with cerebral palsy (CP). There are many studies concerning this problem, however, studies examining long term outcomes of dysphagia using videofluoroscopic study (VFSS) are very rare. The Aim of this study is to investigate long-term outcomes of dysphagia in children with severe CP using initial VFSS. It was a retrospective study and chart review was done from January 2000 to December 2013. Thirty one patients under 18 years who have been diagnosed as CP in outpatient clinic of Rehabilitation Medicine, and who did VFSS were included. Long-term outcomes such as feeding method, height percentile, weight percentile, and body mass index (BMI) were tracked up for at least 3 years by medical records. Significant differences between initial and follow-up datas were investigated. The patients consisted of 18 males and 13 females, and the mean age was 31.0±18.0 months old. 64.5% of patients were doing oral diet, and 25.8% of patients were doing non-oral diet. When comparing VFSS findings among oral feeding patients, oral and non-oral feeding patients, and non-oral feeding patients at initial period, dysphagia severity, supraglottic penetration, and subglottic aspiration showed significant differences. Most of the patients who could feed orally at initial period were found to have the same feeding method at follow-up. But among eight patients who required non-oral feeding initially, three patients became possible to feed orally, and one patient was doing oral and non-oral feeding method together at follow-up. Follow up feeding method showed correlation with dysphagia severity by initial VFSS. Weight percentile was decreased in patients with GMFCS level V at follow up, which may represent poor nutritional status due to severe dysphagia compared to other patients. Initial VFSS severity would play a significant role in making an assumption about future diet in children with severe CP. Patients with GMFCS level V seem to have serious dysphagia at follow up and have nutritional deficiency over time, therefore, more careful nutritional support is needed in children with severe CP are suggested.

Keywords: cerebral palsy, child, dysphagia, videofluoroscopic study

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2514 The Effect of Substrate Temperature on the Structural, Optical, and Electrical of Nano-Crystalline Tin Doped-Cadmium Telluride Thin Films for Photovoltaic Applications

Authors: Eman A. Alghamdi, A. M. Aldhafiri

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It was found that the induce an isolated dopant close to the middle of the bandgap by occupying the Cd position in the CdTe lattice structure is an efficient factor in reducing the nonradiative recombination rate and increasing the solar efficiency. According to our laboratory results, this work has been carried out to obtain the effect of substrate temperature on the CdTe0.6Sn0.4 prepared by thermal evaporation technique for photovoltaic application. Various substrate temperature (25°C, 100°C, 150°C, 200°C, 250°C and 300°C) was applied. Sn-doped CdTe thin films on a glass substrate at a different substrate temperature were made using CdTe and SnTe powders by the thermal evaporation technique. The structural properties of the prepared samples were determined using Raman, x-Ray Diffraction. Spectroscopic ellipsometry and spectrophotometric measurements were conducted to extract the optical constants as a function of substrate temperature. The structural properties of the grown films show hexagonal and cubic mixed structures and phase change has been reported. Scanning electron microscopy (SEM) reviled that a homogenous with a bigger grain size was obtained at 250°C substrate temperature. The conductivity measurements were recorded as a function of substrate temperatures. The open-circuit voltage was improved by controlling the substrate temperature due to the improvement of the fundamental material issues such as recombination and low carrier concentration. All the result was explained and discussed on the biases of the influences of the Sn dopant and the substrate temperature on the structural, optical and photovoltaic characteristics.

Keywords: CdTe, conductivity, photovoltaic, ellipsometry

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2513 Convective Hot Air Drying of Different Varieties of Blanched Sweet Potato Slices

Authors: M. O. Oke, T. S. Workneh

Abstract:

Drying behaviour of blanched sweet potato in a cabinet dryer using different five air temperatures (40-80oC) and ten sweet potato varieties sliced to 5 mm thickness were investigated. The drying data were fitted to eight models. The Modified Henderson and Pabis model gave the best fit to the experimental moisture ratio data obtained during the drying of all the varieties while Newton (Lewis) and Wang and Singh models gave the least fit. The values of Deff obtained for Bophelo variety (1.27 x 10-9 to 1.77 x 10-9 m2/s) was the least while that of S191 (1.93 x 10-9 to 2.47 x 10-9 m2/s) was the highest which indicates that moisture diffusivity in sweet potato is affected by the genetic factor. Activation energy values ranged from 0.27-6.54 kJ/mol. The lower activation energy indicates that drying of sweet potato slices requires less energy and is hence a cost and energy saving method. The drying behavior of blanched sweet potato was investigated in a cabinet dryer. Drying time decreased considerably with increase in hot air temperature. Out of the eight models fitted, the Modified Henderson and Pabis model gave the best fit to the experimental moisture ratio data on all the varieties while Newton, Wang and Singh models gave the least. The lower activation energy (0.27-6.54 kJ/mol) obtained indicates that drying of sweet potato slices requires less energy and is hence a cost and energy saving method.

Keywords: sweet potato slice, drying models, moisture ratio, moisture diffusivity, activation energy

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2512 Predicting Intentions of Physical Activity in Patients with Coronary Artery Disease: Attitudes, Subjective Norms and Perceived Behavioral Control

Authors: Shadi Kanan, Ghada Shahrour, Barbara Broome, Donna Bernert, Muntaha Alibrahim, Dana Hansen

Abstract:

Coronary artery disease is responsible for over 7 million deaths a year worldwide. In developing countries, such as Jordan, the incidence of coronary artery disease exceeds that of developed countries. One contributing factor to this disparity is decreased physical activity among the population, for reasons related to specific cultural and religious values. Using the theory of planned behaviour, the purpose of this study was to investigate the intentions of Jordanian patients with coronary artery disease regarding physical activity. A total of 109 patients with coronary artery disease were recruited for this cross-sectional study from King Abdullah University Hospital in Jordan. A 15-item questionnaire based on the theory of planned behaviour was used to assess participants’ attitudes, subjective norms, perceived behavioural control and intentions towards engagement in physical activity. Perceived behavioural control was found to have the strongest significant relationship with participants’ intentions to engage in physical activity. Barriers to physical activity included lack of time, lack of support from family or friends, and feelings of exhaustion. Lifestyle interventions for patients with coronary artery disease should focus on fostering a sense of control over the environment to encourage patients to engage in physical activity.

Keywords: coronary artery disease, perceived behavioural control, subjective norms, theory of planned behaviour

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2511 Raising Linguistic Awareness through Metalinguistic Written Corrective Feedback

Authors: Orit Zeevy-Solovey

Abstract:

Grammar has traditionally been taught for its own sake, emphasizing rules and drills. However, in recent years, more emphasis is given to communicative competence. Current research suggests that form-focused instruction is notably efficient when incorporated in a meaningful communicative context. It is maintained that writing tasks related to the students’ academic fields will encourage them to express themselves openly in topics that are close to their hearts, without feeling too uneasy about grammatical forms. The teacher can further reduce students’ apprehension of grammar by announcing that credit will be given for merely doing the task and that grammar mistakes will not affect the grade. Students’ linguistic errors can then be corrected by giving metalinguistic feedback which involves providing learners with some kind of explicit remark about the nature of the errors they have made. Research has also shown that learners’ developmental readiness is an important factor influencing the effectiveness of written corrective feedback. Larger effect sizes appear as the proficiency level is higher. The purposes of this paper are to demonstrate how grammar can be taught indirectly through writing tasks, and more specifically, how the use of metalinguistic written corrective feedback given to advanced English as a Foreign Language (EFL) students can raise their linguistic awareness. Since errors are not directly corrected, the students have to work out the corrections needed through exploring grammar books and websites. Longitudinal studies of metalinguistic written corrective feedback comparing the number of errors in students’ first and fourth compositions have shown a decrease in errors.

Keywords: EFL, linguistic awareness, metalinguistic corrective feedback, teaching grammar through writing

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2510 Tomato Endophytes Trichoderma asperellum AAUTLF and Stenotrophomonas maltophilia D1B Exhibits Plant Growth-Promotion and Fusarium Wilt Suppression

Authors: Bandana Saikia, Ashok Bhattacharyya

Abstract:

Endophytic microbes and their metabolites positively impact overall plant health, which may have a potential implication in agriculture. In the present study, 177 bacterial endophytes and 57 fungal endophytes were isolated, with the highest recovery rate from tomato roots. A maximum of 112 endophytes were isolated during monsoon, followed by 64 isolates and 58 isolates isolated during pre-monsoon and post-monsoon periods, respectively, indicating the rich diversity in bacterial and fungal endophytes of tomato crops from different locations of Assam, India. Further, the endophytes were evaluated for their antagonistic potential against Fusarium oxysporum f. sp. lycopersici. Fungal endophytic isolate AAUTLF (Endophytic Fungi of Tomato Leaf from Assam Agricultural University, Assam, India area) and bacterial endophyte D1B (Endophytic bacteria of tomato from Dhemiji, India district) showed the highest antifungal activity against the pathogen both in vitro and in vivo. Based on 5.8 rDNA sequence analysis of fungal and 16S rDNA sequence of bacteria endophytes, the most effective fungal and bacterial isolates against FOL were identified as Trichoderma asperellum AAUTLF and Stenotrophomonas maltophilia D1B, respectively. The isolates showed an antagonistic effect against Fusarium oxysporum f.sp. lycopersici in-vitro and reduced the disease index of Fusarium wilt in tomatoes by 64.4% under pot conditions. Trichoderma asperellum AAUTLF produced an antifungal compound viz., 6-pentyl-2H-pyran-2-one, which also possesses growth-promoting characteristics. The bacteria Stenotrophomonas maltophilia D1B produced antifungal compounds, including benzothiazole, oleic acid, phenylacetic acid, and 3-(Hydroxy-phenyl-methyl)-2,3-dimethyl-octan-4-one. This would be of high importance for the source of antagonistic strains and biocontrol of tomato Fusarium wilt, as well as other plant fungal diseases.

Keywords: root endophytes, Stemotrophomonas, Trichoderma, benzothiazole, 6-pentyl-2H-pyran-2-one

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2509 GIS Data Governance: GIS Data Submission Process for Build-in Project, Replacement Project at Oman electricity Transmission Company

Authors: Rahma Saleh Hussein Al Balushi

Abstract:

Oman Electricity Transmission Company's (OETC) vision is to be a renowned world-class transmission grid by 2025, and one of the indications of achieving the vision is obtaining Asset Management ISO55001 certification, which required setting out a documented Standard Operating Procedures (SOP). Hence, documented SOP for the Geographical information system data process has been established. Also, to effectively manage and improve OETC power transmission, asset data and information need to be governed as such by Asset Information & GIS department. This paper will describe in detail the current GIS data submission process and the journey for developing it. The methodology used to develop the process is based on three main pillars, which are system and end-user requirements, Risk evaluation, data availability, and accuracy. The output of this paper shows the dramatic change in the used process, which results subsequently in more efficient, accurate, and updated data. Furthermore, due to this process, GIS has been and is ready to be integrated with other systems as well as the source of data for all OETC users. Some decisions related to issuing No objection certificates (NOC) for excavation permits and scheduling asset maintenance plans in Computerized Maintenance Management System (CMMS) have been made consequently upon GIS data availability. On the Other hand, defining agreed and documented procedures for data collection, data systems update, data release/reporting and data alterations has also contributed to reducing the missing attributes and enhance data quality index of GIS transmission data. A considerable difference in Geodatabase (GDB) completeness percentage was observed between the years 2017 and year 2022. Overall, concluding that by governance, asset information & GIS department can control the GIS data process; collect, properly record, and manage asset data and information within the OETC network. This control extends to other applications and systems integrated with/related to GIS systems.

Keywords: asset management ISO55001, standard procedures process, governance, CMMS

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2508 Screening Ecological Risk Assessment at an Old Abandoned Mine in Northern Taiwan

Authors: Hui-Chen Tsai, Chien-Jen Ho, Bo-Wei Power Liang, Ying Shen, Yi-Hsin Lai

Abstract:

Former Taiwan Metal Mining Corporation and its associated 3 wasted flue gas tunnels, hereinafter referred to as 'TMMC', was contaminated with heavy metals, Polychlorinated biphenyls (PCBs) and Total Petroleum Hydrocarbons (TPHs) in soil. Since the contamination had been exposed and unmanaged in the environment for more than 40 years, the extent of the contamination area is estimated to be more than 25 acres. Additionally, TMMC is located in a remote, mountainous area where almost no residents are residing in the 1-km radius area. Thus, it was deemed necessary to conduct an ecological risk assessment in order to evaluate the details of future contaminated site management plan. According to the winter and summer, ecological investigation results, one type of endangered, multiple vulnerable and near threaten plant was discovered, as well as numerous other protected species, such as Crested Serpent Eagle, Crested Goshawk, Black Kite, Brown Shrike, Taiwan Blue Magpie were observed. Ecological soil screening level (Eco-SSLs) developed by USEPA was adopted as a reference to conduct screening assessment. Since all the protected species observed surrounding TMMC site were birds, screening ecological risk assessment was conducted on birds only. The assessment was assessed mainly based on the chemical evaluation, which the contamination in different environmental media was compared directly with the ecological impact levels (EIL) of each evaluation endpoints and the respective hazard quotient (HQ) and hazard index (HI) could be obtained. The preliminary ecological risk assessment results indicated HI is greater than 1. In other words, the biological stressors (birds) were exposed to the contamination, which was already exceeded the dosage that could cause unacceptable impacts to the ecological system. This result was mainly due to the high concentration of arsenic, metal and lead; thus it was suggested the above mention contaminants should be remediated as soon as possible or proper risk management measures should be taken.

Keywords: screening, ecological risk assessment, ecological impact levels, risk management

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2507 The Negative Impact of the SARS-CoV-2 Pandemic on Maternal and Child Health, Considering Maternal Experiences of Abuse and Neglect in Childhood

Authors: Franziska Köhler-Dauner, Inka Mayer, Lara Hart, Ute Ziegenhain, Jörg M. Fegert

Abstract:

Preventive isolation and social distancing strategies during the SARS-CoV-2 pandemic have confronted families with a variety of different restrictions and stresses. Especially during this stressful time, children need a stable parental home to avoid developmental disorders. Additional risk factors such as maternal childhood abuse and neglect (CM) experiences may influence mothers' psychosomatic health (pG) and children's physical well-being (kW) during times of increased stress. Our aim was to analyse the interaction between maternal CM, maternal pG and children's kW during the pandemic. Mothers from a well-documented birth cohort to study transgenerational transmission of CM, were included in an online 'pandemic' survey assessing maternal pG and children's physical health during the pandemic. Our mediation analysis showed a significant positive association between the extent of maternal CM experiences, mothers' psychosomatic symptoms and their children's kW. Maternal psychosomatic symptoms significantly mediate the interaction between CM and children's kW; the direct effect remains non-significant when maternal psychosomatic symptoms are included as mediators. Maternal CM appears to be a relevant risk factor for maternal pG and children's kW during the pandemic. Maternal CM experiences seem to influence the way parents cope with stressful situations and increase the risk of suffering from depressive symptoms. The latter also affect their children's kW. Our findings underline the importance of carefully assessing the specific situation of families with children and offering individually adapted help to help families survive the pandemic.

Keywords: pandemic, maternal health, child health, abuse, neglect, maternal experiences

Procedia PDF Downloads 138
2506 Experimental Investigation of Recycling Cementitious Materials in Low Strength Range for Sustainability and Affordability

Authors: Mulubrhan Berihu

Abstract:

Due to the design versatility, availability, and cost efficiency, concrete continues to be the most used construction material on earth. However, the production of Portland cement, the primary component of concrete mix is causing to have a serious effect on environmental and economic impacts. This shows there is a need to study using of supplementary cementitious materials (SCMs). The most commonly used supplementary cementitious materials are wastes, and the use of these industrial waste products has technical, economic, and environmental benefits besides the reduction of CO2 emission from cement production. This paper aims to document the effect on the strength property of concrete due to the use of low cement by maximizing supplementary cementitious materials like fly ash. The amount of cement content was below 250 kg/m3, and in all the mixes, the quantity of powder (cement + fly ash) is almost kept at about 500 kg. According to this, seven different cement content (250 kg/m3, 195 kg/m3, 150 kg/m3, 125 kg/m3, 100 kg/m3, 85 kg/m3, 70 kg/m3) with different amount of replacement of SCMs was conducted. The mix proportion was prepared by keeping the water content constant and varying the cement content, SCMs, and water-to-binder ratio. Based on the different mix proportions of fly ash, a range of mix designs was formulated. The test results showed that using up to 85 kg/m3 of cement is possible for plain concrete works like hollow block concrete to achieve 9.8 Mpa, and the experimental results indicate that strength is a function of w/b. The experiment result shows a big difference in gaining of compressive strength from 7 days to 28 days and this obviously shows the slow rate of hydration of fly ash concrete. As the w/b ratio increases, the strength decreases significantly. At the same time, higher permeability was seen in the specimens which were tested for three hours than one hour.

Keywords: efficiency factor, cement content, compressive strength, mix proportion, w/c ratio, water permeability, SCMs

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2505 The Effects of Cardiovascular Risk on Age-Related Cognitive Decline in Healthy Older Adults

Authors: A. Badran, M. Hollocks, H. Markus

Abstract:

Background: Common risk factors for cardiovascular disease are associated with age-related cognitive decline. There has been much interest in treating modifiable cardiovascular risk factors in the hope of reducing cognitive decline. However, there is currently no validated neuropsychological test to assess the subclinical cognitive effects of vascular risk. The Brief Memory and Executive Test (BMET) is a clinical screening tool, which was originally designed to be sensitive and specific to Vascular Cognitive Impairment (VCI), an impairment characterised by decline in frontally-mediated cognitive functions (e.g. Executive Function and Processing Speed). Objective: To cross-sectionally assess the validity of the BMET as a measure of the subclinical effects of vascular risk on cognition, in an otherwise healthy elderly cohort. Methods: Data from 346 participants (57 ± 10 years) without major neurological or psychiatric disorders were included in this study, gathered as part of a previous multicentre validation study for the BMET. Framingham Vascular Age was used as a surrogate measure of vascular risk, incorporating several established risk factors. Principal Components Analysis of the subtests was used to produce common constructs: an index for Memory and another for Executive Function/Processing Speed. Univariate General Linear models were used to relate Vascular Age to performance on Executive Function/Processing Speed and Memory subtests of the BMET, adjusting for Age, Premorbid Intelligence and Ethnicity. Results: Adverse vascular risk was associated with poorer performance on both the Memory and Executive Function/Processing Speed indices, adjusted for Age, Premorbid Intelligence and Ethnicity (p=0.011 and p<0.001, respectively). Conclusions: Performance on the BMET reflects the subclinical effects of vascular risk on cognition, in age-related cognitive decline. Vascular risk is associated with decline in both Executive Function/Processing Speed and Memory groups of subtests. Future studies are needed to explore whether treating vascular risk factors can effectively reduce age-related cognitive decline.

Keywords: age-related cognitive decline, vascular cognitive impairment, subclinical cerebrovascular disease, cognitive aging

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2504 A Survey of Types and Causes of Medication Errors and Related Factors in Clinical Nurses

Authors: Kouorsh Zarea, Fatemeh Hassani, Samira Beiranvand, Akram Mohamadi

Abstract:

Background and Objectives: Medication error in hospitals is a major cause of the errors which disrupt the health care system. The aim of this study was to assess the nurses’ medication errors and related factors. Material and methods: This was a descriptive study on 225 nurses in various hospitals, selected through multistage random sampling. Data was collected by three researcher made tools; demographic, medication error and related factors questionnaires. Data was analyzed by descriptive statistics, Chi-square, Kruskal-Wallis, One-way analysis of variance. Results: Based on the results obtained, the type of medication errors giving drugs to patients later or earlier (55.6%), multiple oral medication together regardless of their interactions (36%) and the postoperative analgesic without a prescription (34.2%), respectively. In addition, factors such as the shortage of nurses to patients’ ratio (57.3%), high load functions (51.1%) and fatigue caused by the extra work (40.4%), were the most important factors affecting the incidence of medication errors. The fear of legal issues (40%) are the most important factor is the lack of reported medication errors. Conclusions: Based on the results, effective management and promotion motivate nurses. Therefore, increasing scientific and clinical expertise in the field of nursing medication orders is recommended to prevent medication errors in various states of nursing intervention. Employing experienced staff in areas with high risk of medication errors and also supervising less-experienced staff through competent personnel are also suggested.

Keywords: medication error, nurse, clinical care, drug errors

Procedia PDF Downloads 266
2503 Artificial Intelligence in the Design of a Retaining Structure

Authors: Kelvin Lo

Abstract:

Nowadays, numerical modelling in geotechnical engineering is very common but sophisticated. Many advanced input settings and considerable computational efforts are required to optimize the design to reduce the construction cost. To optimize a design, it usually requires huge numerical models. If the optimization is conducted manually, there is a potentially dangerous consequence from human errors, and the time spent on the input and data extraction from output is significant. This paper presents an automation process introduced to numerical modelling (Plaxis 2D) of a trench excavation supported by a secant-pile retaining structure for a top-down tunnel project. Python code is adopted to control the process, and numerical modelling is conducted automatically in every 20m chainage along the 200m tunnel, with maximum retained height occurring in the middle chainage. Python code continuously changes the geological stratum and excavation depth under groundwater flow conditions in each 20m section. It automatically conducts trial and error to determine the required pile length and the use of props to achieve the required factor of safety and target displacement. Once the bending moment of the pile exceeds its capacity, it will increase in size. When the pile embedment reaches the default maximum length, it will turn on the prop system. Results showed that it saves time, increases efficiency, lowers design costs, and replaces human labor to minimize error.

Keywords: automation, numerical modelling, Python, retaining structures

Procedia PDF Downloads 51