Search results for: common consequence effect

Authors: Anusree Ghosh, Nahid Morshed, Tapas Ranjan Chakraborty, Moniruzzaman Khan, Liakath Ali

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To establish the Bangabandhu Sheikh Mujib Shilpa Nagar in Mirsarai, Chattogram land was reclaimed from the river mouth of the Feni River in the Bay of Bangle. The sandy land has a salinity of 9.5 EC ds/m, and the water of the adjacent Bay was 13.2 EC ds/m during winter, i.e., it has moderate salinity. The selection of plant species for the plantation was following the local practices. Mangrove plantation in a such landscape is not common in the country, and some actions towards the plantation seem ineffective and could be accomplished differently. The aim of this paper is to analyze the trial and develop a strategy for mangrove afforestation in reclaimed land where the tidal effect does not occur year-round. Though the Keora (Sonneratia apetala) is the priority species in a typical mangrove plantation, the success rate is comparatively high for the Baen (Avcennia officinalis) and Sada Baen (Avicennia alba). The natural growth was recorded for Keora, Goran (Ceriops decandra), Lal Jhau (Tamarix dioica) and Baen. Though there was the natural growth of Durba grass (Cynodon dactylon) and Motha Gash (Cyperus rotundus), no growth of climber was reported at the early stage of the natural growth. The transplanted growth of Keora, Gewa (Excoecaria agallocha), and Baen was found not suitable for plantation. The saplings growing from the viviparous germinated bean show no germination failure. Since the plantation site remains dry for 5 months, there was irrigation from the river; though it resulted in an increase in land salinity. To increase fertility, cow dung was used, and green manuring by planting Doincha (Sesbania bispinosa) shows a very insignificant contribution. The plantation of, only one and a half years old, is now a habitat of more than 100 species. The learning from the mangrove plantation from August 2021 to February 2023 assumes that in reclaimed land where there is inundation during monsoon only and salinity is moderate, the plantation from viviparous germinated Baen is better.

Keywords: mangrove plantation, reclaimed land, climate change, habitat restoration

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Authors: Varun Mittal, Shishir Sinha

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The present experimental study focused on the hardness behavior of bagasse fiber-epoxy composites. The relationship between bagasse fiber content and effect of chemical treatment on bagasse fiber as a function of Brinell hardness of bagasse fiber epoxy was investigated. Bagasse fiber was treated with sodium hydroxide followed by acrylic acid before they were reinforced with epoxy resin. Compared hardness properties with the untreated bagasse filled epoxy composites. It was observed that Brinell hardness increased up to 15 wt% fiber content and further decreases, however, chemical treatment also improved the hardness properties of composites.

Keywords: bagasse fiber, composite, hardness, sodium hydroxide

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Authors: S. P. Singh, Shweta Gupta, Kshama Dwivedi, Shivangi Singh

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Aim: To compare the postoperative pupil cosmesis, mydriasis, and anterior chamber depth (ACD) in traumatic and congenital iris defects after Single-Pass Four-Throw pupilloplasty (SFTP). Method: SFTP was performed along with cataract surgery in 6 patients, each of congenital and traumatic iris defects and pupil size, mydriasis, and ACD was compared after three months. Results: SFTP was successful in repairing congenital and traumatic cases except in 1 traumatic case with a large iris defect. Horizontal pupil diameter decreased while ACD increased in both groups and was comparable between the two groups. The traumatic group showed a significant decrease in pupil diameter while there was an insignificant change in the horizontal pupil diameter in the congenital group. Mydriasis was adequate for fundus examination and was comparable between the two groups. The effect of SFTP on ACD was inconclusive due to the confounding effect of cataract surgery. The incidence of iris atrophy was equal in both groups. Conclusion: SFTP results in anatomical and functional restoration in cases of iris defects with no inadvertent effect on mydriasis.

Keywords: anterior chamber depth, mydriasis, pupil cosmesis, single-pass four-throw pupilloplasty

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Authors: Cristina Busuioc, Georgeta Voicu, Sorin-Ion Jinga

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The human bone presents in its dry form piezoelectric properties, which means that a mechanical stress results in electric polarization and an applied electric field causes strain. The immediate consequence was the revealing of piezoelectricity role in bone remodelling, as well as the integration of ceramic materials with piezoelectric behaviour in the composition of unitary or composite biomaterials. Thus, we prepared hydroxyapatite - collagen hybrid materials with barium titanate addition in order to achieve a better osseointegration. Barium titanate powder synthesized by a combined sol-gel-hydrothermal method, commercial hydroxyapatite and laboratory extracted collagen gel were employed as starting materials. Before the composites, fabrication, the powder with piezoelectric features was characterized in detail from the compositional, structural, morphological and electrical point of view. The next step was to elucidate the influence of barium titanate presence especially on the biological properties of the final materials. The biocompatibility of the hybrid supports without or with piezoelectric addition was investigated on mouse osteoblast cells through LDH cytotoxicity assay, LIVE/DEAD cell viability assay, and MTT cell proliferation assay. All results indicated that the analysed materials do not exert cytotoxic effects and present the ability to sustain cell survival and to promote their proliferation. In conclusion, barium titanate nanoparticles exhibit a good biocompatibility and osteoinductive properties, while the derived composite materials based on hydroxyapatite as oxide phase and collagen as polymeric phase can be successfully used for tissue engineering applications.

Keywords: barium titanate, hybrid composites, piezoelectricity, tissue engineering

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Authors: Radnoosh Mirzajani, Ebrahim Mirzajani, Heshmatollah Ebrahimi-Najafabadi

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Introduction: Hydrogen peroxide can be produced over the interaction of sodium dodecyl sulfate (SDS) with hemoglobin which would facilitate the oxidation process of hemoglobin. The presence of ascorbic acid (AA) can hinder the extreme oxidation of oxyhemoglobin. Methods: Hemoglobin was purified from blood samples according to the method of Williams. UV-V is spectra of Hb solutions mixed with different concentrations of SDS and AA were recorded. Chemical components, concentration, and spectral profiles were estimated using MCR-ALS techniques. Results: The intensity of soret band of OxyHb decreased due to the interaction of Hb with SDS. Furthermore, changes were also observed for peaks at 575 and 540. Subspace plots confirm the presence of OxyHb, MetHb, and Hemichrom in each mixture. The resolved concentration profiles using MCR-ALS reveal that the mole fraction of OxyHb increased upon the presence of AA up to a concentration level of 3 mM. The higher concentration of AA shows a reverse effect. AA demonstrated a dual effect on the interaction of hemoglobin with SDS. AA disturbs the interaction of SDS and hemoglobin and exhibits an antioxidative effect. However, it caused a tiny decrease in the mole fraction of OxyHb. Conclusions: H2O2 produces upon the interaction of OxyHb with SDS. Oxidation of OxyHb facilitates due to overproduction of H2O2. Ascorbic acid interacts with H2O2 to form dehydroascorbic acid. Furthermore, the available free SDS was reduced because the Gibbs free energy for micelle production of SDS became more negative in the presence of AA.

Keywords: hemoglobin, ascorbic acid, sodium dodecyl sulfate, multivariate curve resolution, antioxidant

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Authors: Nejla Fourati, Zied Fessi, Fatma Dhouib, Wicem Siala, Leila Farhat, Afef Khanfir, Wafa Mnejja, Jamel Daoud

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Purpose: Radiation induced hypothyroidism in nasopharyngeal cancer (NPC) ranged from 15% to 55%. In reported data, it is considered as a common late complication of definitive radiation and is mainly observed 2 years after the end of treatment. The aim of this study was to evaluate the incidence of early hypothyroidism within 6 months after radiotherapy. Patients and methods: From June 2017 to February 2020, 35 patients treated with concurrent chemo-radiotherapy (CCR) for NPC were included in this prospective study. Median age was 49 years [23-68] with a sex ratio of 2.88. All patients received intensity modulated radiotherapy (IMRT) at a dose of 69.96 Gy in 33 daily fractions with weekly cisplatin (40mg/m²) chemotherapy. Thyroid stimulating hormone (TSH) and Free Thyroxine 4 (FT4) dosage was performed before the start of radiotherapy and 6 months after. Different dosimetric parameters for the thyroid gland were reported: the volume (cc); the mean dose (Dmean) and the %age of volume receiving more than 45 Gy (V45Gy). Wilcoxon Test was used to compare these different parameters between patients with or without hypothyroidism. Results: At baseline, 5 patients (14.3%) had hypothyroidism and were excluded from the analysis. For the remaining 30 patients, 9 patients (30%) developed a hypothyroidism 6 months after the end of radiotherapy. The median thyroid volume was 10.3 cc [4.6-23]. The median Dmean and V45Gy were 48.3 Gy [43.15-55.4] and 74.8 [38.2-97.9] respectively. No significant difference was noted for all studied parameters. Conclusion: Early hypothyroidism occurring within 6 months after CCR for NPC seems to be a common complication (30%) that should be screened. Good patient monitoring with regular dosage of TSH and FT4 makes it possible to treat hypothyroidism in asymptomatic phase. This would be correlated with an improvement in the quality of life of these patients. The results of our study do not show a correlation between the thyroid doses and the occurrence of hypothyroidism. This is probably related to the high doses received by the thyroid in our series. These findings encourage more optimization to limit thyroid doses and then the risk of radiation-induced hypothyroidism

Keywords: nasopharyngeal carcinoma, hypothyroidism, early complication, thyroid dose

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Authors: Ratri Werdiningtyas, Yongping Wei, Andrew Western

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The status quo of social-ecological systems is the results of not only natural processes but also the accumulated consequence of policies applied in the past. Often water management objectives are challenging and are only achieved to a limited degree on the ground. In choosing water management approaches, it is important to account for current conditions and important differences due to varied histories. Since the mid-nineteenth century, Victorian water management has evolved through a series of policy regime shifts. The main goal of this research to explore and identify the stages of the evolution of the water policy instruments as practiced in Victoria from 1890-2016. This comparative historical analysis has identified four stages in Victorian policy instrument development. In the first stage, the creation of policy instruments aimed to match the demand and supply of the resource (reserve condition). The second stage begins after natural system alone failed to balance supply and demand. The focus of the policy instrument shifted to an authority perspective in this stage. Later, the increasing number of actors interested in water led to another change in policy instrument. The third stage focused on the significant role of information from different relevant actors. The fourth and current stage is the most advanced, in that it involved the creation of a policy instrument for synergizing the previous three focal factors: reserve, authority, and information. When considering policy in other jurisdiction, these findings suggest that a key priority should be to reflect on the jurisdictions current position among these four evolutionary stages and try to make improve progressively rather than directly adopting approaches from elsewhere without understanding the current position.

Keywords: policy instrument, policy transformation, socio-ecolgical system, water management

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Authors: Olayinka M. Ayannuga

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This study explored the effect of cognitive reframe in reducing depression among Senior Secondary School Adolescents. It adopted a pre-test, post-test, control quasi-experimental research design with a 2x2 factorial matrix. Participants included 120 depressed adolescents randomly drawn from public Senior Secondary School Two (SSS.II) students in Lagos State, Nigeria. Sixty participants were randomly selected and assigned to the treatment and control groups. Participants in the Cognitive Reframe (CR) group were trained for 8 weeks, while those in the Control group were given a placebo. Two instruments were used for data collection namely: Self – Esteem Scale (SES: Rosenberg 1965: α = 0.85), and The Self Rating Depression Scale (SDS: Zung, 1972; α 0 = 0.87) were administered at pretest level. However, only the Self-Rating Depression Scale (SDS) was re-administered at post-test to measure the effect of the intervention. The results revealed that there was a significant effect of cognitive reframe training programmes on secondary school adolescents’ depression, also there were significant effects of self-esteem on secondary school adolescents’ depression. The study showed that the technique is capable of reducing depression among adolescents. It was recommended, amongst others, that Counselling psychologists, Curriculum planners and Teachers could explore incorporating the contents of cognitive reframe into the secondary school curriculum for students’ capacity building to reduce depression tendencies.

Keywords: adolescents, cognitive reframe, depression, self – esteem

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Authors: Devante K. Barrett

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The objective of this research is to evaluate the association between one's subjective tiredness as it relates to the Stroop effect and the identification of subjective tiredness among adolescents. Individuals with a high subjective tired score are more likely to have a lower reaction time in incongruent trials. It is understood that sleep is an overlooked phenomenon in psychological research, and with the utilization of adequate testing, ways to address sleep in this manner may no longer be an issue of concern in the future. Sleep researchers often obtain significant results by way of Stroop testing. The caveat is that the integrity of Stroop testing can be negatively affected by various external factors. The propensity for interference to occur is caused by the automatic process of reading. This is deemed one of the most detrimental issues in understanding the dimensions of sleep. Interference subsequently decreases response time in the identification of the ink color. Considering the fact that the Stroop task is helpful in evaluating cognitive function in clinical populations, results should be interpreted cautiously due to the multitude of variables that may affect performance. When planning studies and analyzing data related to the Stroop effect, researchers must take individual differences and environmental factors into consideration. Having a thorough understanding of the Stroop effect can aid in the development of initiatives targeted at enhancing attention span and cognitive control across a range of demographics. Age-related changes in sleep patterns and selective attention from childhood to adolescence are key points of consideration in various areas of research, which are primarily focused on age-dependent performance in vigilant attention among young populations. Thus, findings related to Stroop testing may be deemed eligible to provide meaningful implications regarding vigilant attention among such populations. With respect to future research, this can be assessed by way of neuroimaging of brain-regions associated with selective attention and circadian cycles.

Keywords: sleep, selective attention, Stroop effect, cognitive function, sleep hygiene, vigilant attention

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Authors: Akpokiere Ugbede Roseline

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Chemistry is an activity oriented subject in which many students achievement over the years are not encouraging. Among the reasons found to be responsible for student’s poor performance in chemistry are ineffective teaching strategies. This study, therefore, sought to determine the effect of guided inquiry, guided inquiry with demonstration, and demonstration with conventional approach on pre-service teachers’ cognitive attainment and practical skills acquisition on stoichiometry and chemical reactions in practical chemistry, Two research questions and hypotheses were each answered and tested respectively. The study was a quasi-experimental research involving 50 students in each of the experimental groups and 50 students in the control group. Out of the five instruments used for the study, three were on stimulus and two on response (Test of Cognitive Attainment and Test of Practical Skills in Chemistry) instruments administered, and dataobtained were analyzed with t-test and Analysis of Variance. Findings revealed, among others, that there was a significant effect of treatments on students' cognitive attainment and on practical skills acquisition. Students exposed to guided inquiry (with/without demonstration) strategies achieved better than those exposed to demonstration with conventional strategy. It is therefore recommended, among others, that Lecturers in Colleges of Education should utilize the guided inquiry strategy for teaching concepts in chemistry.

Keywords: instructional strategy, practical chemistry, learning outcomes, pre-service teachers

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Authors: K. Yu Vlasova, M. A. Abakumov, H. Wishwarsao, M. Sokolsky, N. V. Nukolova, A. G. Majouga, Y. I. Golovin, N. L. Klyachko, A. V. Kabanov

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Introduction:Nowadays pharmaceutical medicine is aimed to create systems for combined therapy, diagnostic, drug delivery and controlled release of active molecules to target cells. Magnetic nanoparticles (MNPs) are used to achieve this aim. MNPs can be applied in molecular diagnostics, magnetic resonance imaging (T1/T2 contrast agents), drug delivery, hyperthermia and could improve therapeutic effect of drugs. The most common drug containers, containing MNPs, are liposomes, micelles and polymeric molecules bonded to the MNPs surface. Usually superparamagnetic nanoparticles are used (the general diameter is about 5-6 nm) and all effects of high frequency magnetic field (MF) application are based on Neel relaxation resulting in heating of surrounded media. In this work we try to develop a new method to improve drug release from MNPs under super low frequency MF. We suppose that under low frequency MF exposures the Brown’s relaxation dominates and MNPs rotation could occur leading to conformation changes and release of bioactive molecules immobilized on MNPs surface.The aim of this work was to synthesize different systems with active drug (biopolymers coated MNPs nanoclusters with immobilized enzymes and doxorubicin (Dox) loaded magnetic liposomes/micelles) and investigate the effect of super low frequency MF on these drug containers. Methods: We have synthesized MNPs of magnetite with magnetic core diameter 7-12 nm . The MNPs were coated with block-copolymer of polylysine and polyethylene glycol. Superoxide dismutase 1 (SOD1) was electrostatically adsorbed on the surface of the clusters. Liposomes were prepared as follow: MNPs, phosphatidylcholine and cholesterol were dispersed in chloroform, dried to get film and then dispersed in distillated water, sonicated. Dox was added to the solution, pH was adjusted to 7.4 and excess of drug was removed by centrifugation through 3 kDa filters. Results: Polylysine coated MNPs formed nanosized clusters (as observed by TEM) with intensity average diameter of 112±5 nm and zeta potential 12±3 mV. After low frequency AC MF exposure we observed change of immobilized enzyme activity and hydrodynamic size of clusters. We suppose that the biomolecules (enzymes) are released from the MNPs surface followed with additional aggregation of complexes at the MF in medium. Centrifugation of the nanosuspension after AC MF exposures resulted in increase of positive charge of clusters and change in enzyme concentration in comparison with control sample without MF, thus confirming desorption of negatively charged enzyme from the positively charged surface of MNPs. Dox loaded magnetic liposomes had average diameter of 160±8 nm and polydispersity index (PDI) 0.25±0.07. Liposomes were stable in DW and PBS at pH=7.4 at 370C during a week. After MF application (10 min of exposure, 50 Hz, 230 mT) diameter of liposomes raised to 190±10 nm and PDI was 0.38±0.05. We explain this by destroying and/or reorganization of lipid bilayer, that leads to changes in release of drug in comparison with control without MF exposure. Conclusion: A new application of low frequency AC MF for drug delivery and controlled drug release was shown. Investigation was supported by RSF-14-13-00731 grant, K1-2014-022 grant.

Keywords: magnetic nanoparticles, low frequency magnetic field, drug delivery, controlled drug release

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Authors: A. Alhelfi, B. Sunden

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Cavitation in cryogenic liquids is widely present in contemporary science. In the current study, we re-examine a previously validated acoustic cavitation model which was developed for a gas bubble in liquid water. Furthermore, simulations of cryogenic fluids including the thermal effect, the effect of acoustic pressure amplitude and the frequency of sound field on the bubble dynamics are presented. A gas bubble (Helium) in liquids Nitrogen, Oxygen and Hydrogen in an acoustic field at ambient pressure and low temperature is investigated numerically. The results reveal that the oscillation of the bubble in liquid Hydrogen fluctuates more than in liquids Oxygen and Nitrogen. The oscillation of the bubble in liquids Oxygen and Nitrogen is approximately similar.

Keywords: cryogenic liquids, cavitation, rocket engineering, ultrasound

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Authors: Hoang Van Ngoc, Nguyen Vu Nhan, Nguyen Quang Bau

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The light-effect in cylindrical quantum wire with an infinite potential for the case of electrons, optical phonon scattering, is studied based on the quantum kinetic equation. The density of the direct current in a cylindrical quantum wire by a linearly polarized electromagnetic wave, a DC electric field, and an intense laser field is calculated. Analytic expressions for the density of the direct current are studied as a function of the frequency of the laser radiation field, the frequency of the linearly polarized electromagnetic wave, the temperature of system, and the size of quantum wire. The density of the direct current in cylindrical quantum wire with an infinite potential for the case of electrons – optical phonon scattering is nonlinearly dependent on the frequency of the linearly polarized electromagnetic wave. The analytic expressions are numerically evaluated and plotted for a specific quantum wire, GaAs/GaAsAl.

Keywords: the light–effect, cylindrical quantum wire with an infinite potential, the density of the direct current, electrons-optical phonon scattering

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Authors: Mohamed Ben Amar, Najib Souissi, Chedly Bradai

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A Taguchi design investigation has been made into the relationship between the ductility and process variables in a squeeze cast 2017A wrought aluminium alloy. The considered process parameters were: squeeze pressure, melt temperature and die preheating temperature. An orthogonal array (OA), main effect, signal-to-noise (S/N) ratio, and the analysis of variance (ANOVA) are employed to analyze the effect of casting parameters. The results have shown that the selected parameters significantly affect the ductility of 2017A wrought Al alloy castings. Optimal squeeze cast process parameters were provided to illustrate the proposed approach and the results were proven to be trustworthy through practical experiments.

Keywords: Taguchi method, squeeze casting, process parameters, ductility, microstructure

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Authors: Bremmy Laksono, Riksa Parikrama, Nur A. Rosyada, Willyanti Soewondo, Dadang S. H. Effendi, Eriska Rianti, Arlette S. Setiawan, Ine Sasmita, Risti S. Primanti, Erna Kurnikasari, Yunia Sribudiani

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Down syndrome (DS) is a chromosomal abnormality characterised by complete 21 chromosome trisomy (classical or non-disjunction), or partial 21 chromosome trisomy (mosaicism), or chromosome rearrangement involving chromosome 21 (translocation). This study was carried out to describe the frequency of DS patients in a research institution in the city of Bandung, Indonesia. This descriptive study also provides a picture of the residential location and surrounding area of their dwellings. This study involved people with DS in various age whose chromosome were evaluated by conventional karyotyping method and FISH. Data were collected from 60 patients with DS from a total 150 patients during the period of September 2015 to August 2016 who were referred to Cell Culture and Cytogenetics Laboratory, Faculty of Medicine Universitas Padjadjaran, Indonesia. Results showed that the most common type of DS was non-disjunction (93%), followed by mosaicism (5%), no patient with translocation DS (0%), and a very rare type of tetrasomy 21 (2%). There were 39 males (65%) and 21 females (35%) of DS patient. Most of them live in suburban area beyond Bandung city (55%) while the rest live inside urban area of Bandung city (45%). They live mostly in dense area of greater Bandung area (65%) and only a few live in mid-density area (25%) and the least live in sparse populated area (10%). Their houses are mostly located in residential estate area (55%), nearby industrial area (37%), and around agricultural area (8%). Based on the study, it could be concluded that non-disjunction DS is the most common type. DS patients referred to the laboratory mostly came from dense residential zone in suburban area outside Bandung city. The low number of DS patients referred to the laboratory for chromosome analysis was the highlight to improve health service for people with genetic disorder. This study offered several information regarding area of DS patients’ residence and the condition of neighbourhood in Bandung city where they live as well.

Keywords: chromosome, descriptive, Down syndrome, prevalence

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Authors: Katherine Sparks, Christopher Ring

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This study aimed to investigate whether dispositional sport-specific mindfulness moderated the moderation effect of conscious processing on the relationship between anxiety and rowing race performance. Using a sport-specific (Rowing-Specific) Reinvestment Scale (RSRS) to measure state conscious processing, we examined the effects of trait sport-related mindfulness on the conscious processes of rowers under competitive racing pressure at a number of UK regattas. 276 rowers completed a survey post competitive race. The survey included the RSRS, mindfulness, a perceived performance rating scale, demographic and race information to identify and record the rower’s actual race performance. Results from the research demonstrated that high levels of dispositional mindfulness are associated with a superior performance under pressure. In relation to the moderating moderation effect, conscious processing amplifies the detrimental effects of anxiety on performance. However, mindfulness, mindful awareness, and mindful non-judgement all proved to attenuate this amplification effect by moderating the conscious processing moderation on the anxiety-performance relationship. Therefore, this study provides initial support for the speculation that dispositional mindfulness can help prevent the deleterious effects of rowing-specific reinvestment under pressure.

Keywords: mindful, reinvestment, under pressure, performance, rowing

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Authors: Kang-Gyu Park, Sun-Jong Park, Hong Jae Yim, Hyo-Gyung Kwak

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This paper attempts to evaluate the effect of fire damage on concrete by using nonlinear resonance vibration method, one of the nonlinear nondestructive method. Concrete exhibits not only nonlinear stress-strain relation but also hysteresis and discrete memory effect which are contained in consolidated materials. Hysteretic materials typically show the linear resonance frequency shift. Also, the shift of resonance frequency is changed according to the degree of micro damage. The degree of the shift can be obtained through nonlinear resonance vibration method. Five exposure scenarios were considered in order to make different internal micro damage. Also, the effect of post-fire-curing on fire-damaged concrete was taken into account to conform the change in internal damage. Hysteretic non linearity parameter was obtained by amplitude-dependent resonance frequency shift after specific curing periods. In addition, splitting tensile strength was measured on each sample to characterize the variation of residual strength. Then, a correlation between the hysteretic non linearity parameter and residual strength was proposed from each test result.

Keywords: nonlinear resonance vibration method, non linearity parameter, splitting tensile strength, micro damage, post-fire-curing, fire damaged concrete

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Authors: MeiBo, ZhaoXing, LuoLei, YuQingkui, TangMin, HanZhengsheng

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The Single Event Transients (SETs) were investigated on 0.18μm PDSOI transistors and 100 series CMOS inverter chain using pulse laser. The effect of different laser energy and device bias for waveform on SET was characterized experimentally, as well as the generation and propagation of SET in inverter chain. In this paper, the effects of struck transistors type and struck locations on SETs were investigated. The results showed that when irradiate NMOSFETs from 100th to 2nd stages, the SET pulse width measured at the output terminal increased from 287.4 ps to 472.9 ps; and when irradiate PMOSFETs from 99th to 1st stages, the SET pulse width increased from 287.4 ps to 472.9 ps. When struck locations were close to the output of the chain, the SET pulse was narrow; however, when struck nodes were close to the input, the SET pulse was broadening. SET pulses were progressively broadened up when propagating along inverter chains. The SET pulse broadening is independent of the type of struck transistors. Through analysis, history effect induced threshold voltage hysteresis in PDSOI is the reason of pulse broadening. The positive pulse observed by oscilloscope, contrary to the expected results, is because of charging and discharging of capacitor.

Keywords: single event transients, pulse laser, partially-depleted silicon-on-insulator, propagation-induced pulse broadening effect

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Authors: Naouel Boussoualim, Hayat Trabsa, Imane Krache, Seddik Khennouf, Noureddine Charef, Lekhmici Arrar, Abderrahmane Baghiani

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Purpose: To evaluate the in-vitro inhibition of xanthine oxidase (purified from bovine milk) by extracts of Lycium arabicum, as well as it is in vivo hypouricemic and renal protective effects. Methods: Four extracts of Lycium arabicum, methanol (CrE), chloroform (ChE), ethyl acetate (EaE) and aqueous (AqE) extracts, were screened for their total phenolics and potential inhibitory effects on purified bovine milk xanthine oxidase (XO) activity by measuring the formation of uric acid or superoxide radical. The mode of inhibition was investigated and compared with the standard drugs, allopurinol, quercitin, and catechin. To evaluate their hypouricemic effect, the extracts were administered to potassium oxonate-induced hyperuricemic mice at a dose of 50 mg/kg body weight. Results: The results showed that EaE had the highest content of phenolic compounds and was the most potent inhibitor of uric acid formation (IC50 = 0.017 ± 0.001 mg/mL) and formation of superoxide (IC50 = 0.035 ± 0.001 mg/ml). Lineweaver-Burk analysis showed that CrE and EaE inhibited XO competitively, whereas the inhibitory activities exerted by ChE and AqE were of a mixed type. Intraperetoneal injection of L. arabicum extracts (50 mg/kg) elicited hypouricemic actions in hyperuricemic mice. Hyperuricemic mice presented a serum uric acid concentration of 4.71 ± 0.29 mg/L but this was reduced to 1.78 ± 0.11 mg/L by EaE, which was the most potent hyporuricemic extract. Conclusion: L. arabicum fractions have a strong inhibitory effect on xanthine oxidase and and also have a significantly lowering effect on serum and liver creatinine and urea levels in hyperuricemic mice.

Keywords: lycium arabicum, uric acid, creatinine, superoxide, phenolic compounds, flavonoids, hyperuricemia

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Authors: Abbasali Abouei Mehrizi, Hamid Hassanzadeh Afrouzi

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Reducing the drag force increases the efficiency of the aircraft and its better performance. Flow control methods delay the phenomenon of flow separation and consequently reduce the reversed flow phenomenon in the separation region and enhance the performance of the lift force while decreasing the drag force and thus improving the aircraft efficiency. Flow control methods can be divided into active and passive types. The use of synthetic jets actuator (SJA) used in this study for NACA GA (W) -2 airfoil is one of the active flow control methods to prevent stall phenomenon on the airfoil. In this research, the relevant airfoil in different angles of attack with and without jets has been compared by OpenFOAM. Also, after achieving the proper SJA position on the airfoil suction surface, the simultaneous effect of two SJAs has been discussed. It was found to have the best effect at 12% chord (C), close to the airfoil’s leading edge (LE). At 12% chord, SJA decreases the drag significantly with increasing lift, and also, the average lift increase was higher than other situations and was equal to 10.4%. The highest drag reduction was about 5% in SJA=0.25C. Then, due to the positive effects of SJA in the 12% and 25% chord regions, these regions were considered for applying dual jets in two post-stall angles of attack, i.e., 16° and 22°.

Keywords: active and passive flow control methods, computational fluid dynamics, flow separation, synthetic jet

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Authors: Yosra Makni Fourati, Sana Masmoudi Mardassi

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This paper investigates the effect of Book-tax conformity on audit quality regarding the proxies of audit fees, auditors’ industry specialization and audit report lag. Using a sample of Canadian firms listed on the Toronto Stock Exchange spanning the years 2006- 2016, we applied an Ordinary Least Squares (OLS) regression to test hypotheses of this research. The authors find that higher Book-tax conformity leads to lower audit fees. They also provide evidence that there is a negative association between Book-tax conformity and auditors’ industry specialization, whereas there is a positive association between Book-tax conformity and audit report lag. Overall, the findings are prominent to better understanding the effect of Book-tax conformity on audit quality and are relevant for academic researchers, practitioners, and regulators. As the paper investigates the relationship of Book-tax conformity and audit quality using a sample of Canadian firms, it brings original insights regarding the importance of audit fees and Book-tax conformity. In addition, it considers the role of auditor’s industry specialization in the relation between audit quality and Book-tax conformity by considering a sample listed on the Toronto Stock Exchange. This paper contributes to the existing literature by highlighting the Canadian setting, to our best knowledge. In addition, our results are prominent to the auditing literature as they introduce a different determinant of auditors’ industry specialization and audit report lag.

Keywords: audit fees, auditors' industry specialization, audit report lag, book-tax conformity

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Authors: Khomkrit Mongkhuntod, Chatchawal Chaichana, Atipoang Nuntaphan

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Feed Water Heater is the important equipment for thermal power plant. The heating temperature from feed heating process is an impact to power plant efficiency or heat rate. Normally, the degradation of feed water heater that operated for a long time is effect to decrease plant efficiency or increase plant heat rate. For Mae Moh power plant, each unit operated more than 20 years. The degradation of the main equipment is effect of planting efficiency or heat rate. From the efficiency and heat rate analysis, Mae Moh power plant operated in high heat rate more than the commissioning period. Some of the equipment were replaced for improving plant efficiency and plant heat rates such as HP turbine and LP turbine that the result is increased plant efficiency by 5% and decrease plant heat rate by 1%. For the target of power generation plan that Mae Moh power plant must be operated more than 10 years. These work is focus on thermal efficiency analysis of feed water heater to compare with the commissioning data for find the way to improve the feed water heater efficiency that may effect to increase plant efficiency or decrease plant heat rate by use heat balance model simulation and economic value add (EVA) method to study the investment for replacing the new feed water heater and analyze how this project can stay above the break-even point to make the project decision.

Keywords: feed water heater, power plant efficiency, plant heat rate, thermal efficiency analysis

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Authors: Aikaterini Tavoulari

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This research aims to address the types of repetitive behaviours (RBs) observed by adults in children with vision impairment (VI) or autism spectrum disorder (ASD), the explanations the adults employ to interpret these behaviours, and the impact RBs have on the child, the caregiver, the professional and society. The underlying reason for this is an attempt to discover any potential differences between two different disabilities in a comparative fashion. The study is based on the interpretivism paradigm and follows a qualitative approach. A comparative case study design based on the ecological systems theory (EST) is adopted. Thirty-five caregivers and accredited professionals were recruited (17 for the VI group, out of whom 8 were caregivers and 9 were professionals, and 18 for the ASD group, out of whom 9 were caregivers and 9 were professionals). Following the completion of a pilot study, all participants were interviewed regarding one specific child – their own child/student – via semi-structured interviews. During the interviews, the researcher used a research diary as a methodological tool and video elicitation as a facilitation tool. A cross-case analysis was conducted, and data were analysed according to the method of thematic analysis. A link has been indicated between VI and ASD, which concerns perceptions about the socially constructed manner in which an RB is perceived. ASD is perceived by the participants as a disability with challenging characteristics, such as an RB. The ASD group perceived RB as linked to ableism, social stigmatisation, and taboo, in contrast to VI, where the existence of RB seems to be a consequence of sensory loss. Bi-directionality of EST seems to have been lost completely, and the macrosystem seems to drive the interactions between the ecological systems.

Keywords: ableism, social stigma, disability, repetitive behaviour, vision impairment, autism spectrum disorder, perceptions

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Authors: Michele Sinico

Abstract:

Usability is significantly influenced by the perceptual characteristics of interfaces. This study investigates the effect of the inclination of elements in a physical interface on the evaluation of perceived usability. In the first experiment, a psychophysical methodology was employed to measure the perceived usability of 15 different washing machine interfaces. A model of perceived usability was adopted, which incorporating four factors: understandability, ease of use, safety, and attractiveness. The results indicate that participants were able to discriminate between the stimuli based on the factors considered. In the second experiment, the inclinations of the interface elements (buttons, LEDs, icons and text labels) were systematically modified. The findings reveal that inclination significantly affects three perceived usability subcomponents: understandability, ease of use, and attractiveness.

Keywords: ergonomics, perceptual usability, interfaces, inclination, washing machine

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Authors: Eung Ryeol Seo, Hee Tae Lim, Eunsuk Bang, Soon Cheol Kweon, Jeoung-Kyo Jeoung, Ji-Hoon Choic

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The object of this study is to investigate the effect of pulsator on washing performance quantitatively for front-loading washer. The front-loading washer with pulsator shows washing performance improvement of 18% and the particle-based body simulation technique has been applied to figure out the relation between washing performance and mechanical forces exerted on textile during washing process. As a result, the mechanical forces, such as collision force and strain force, acting on the textile have turned out to be about twice numerically. The washing performance improvement due to additional pulsate system has been utilized for customers to save 50% of washing time.

Keywords: front-loading washer, mechanical force, fabric movement, pulsator, time-saving

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Authors: Kwok W. Mui, Ling T. Wong, Tsz W. Tsang

Abstract:

Many Hong Kong people nowadays spend most of their lifetime working indoor. Since poor Indoor Air Quality (IAQ) potentially leads to discomfort, ill health, low productivity and even absenteeism in workplaces, a call for establishing statutory IAQ control to safeguard the well-being of residents is urgently required. Although policies, strategies, and guidelines for workplace IAQ diagnosis have been developed elsewhere and followed with remedial works, some of those workplaces or buildings have relatively late stage of the IAQ problems when the investigation or remedial work started. Screening for IAQ problems should be initiated as it will provide information as a minimum provision of IAQ baseline requisite to the resolution of the problems. It is not practical to sample all air pollutants that exit. Nevertheless, as a statutory control, reliable, rapid screening is essential in accordance with a compromise strategy, which balances costs against detection of key pollutants. This study investigates the feasibility of using an IAQ index as a parameter of IAQ control in Hong Kong. The index is a screening parameter to identify the unsatisfactory workplace IAQ and will highlight where a fully effective IAQ monitoring and assessment is needed for an intensive diagnosis. There already exist a number of representative common indoor pollutants based on some extensive IAQ assessments. The selection of pollutants is surrogate to IAQ control consists of dilution, mitigation, and emission control. The IAQ Index and assessment will look at high fractional quantities of these common measurement parameters. With the support of the existing comprehensive regional IAQ database and the IAQ Index by the research team as the pre-assessment probability, and the unsatisfactory IAQ prevalence as the post-assessment probability from this study, thresholds of maintaining the current measures and performing a further IAQ test or IAQ remedial measures will be proposed. With justified resources, the proposed IAQ Index and assessment protocol might be a useful tool for setting up a practical public IAQ surveillance programme and policy in Hong Kong.

Keywords: assessment, index, indoor air quality, surveillance programme

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Authors: M. Boumaiza, S. Mohamadi, B. Moussai

Abstract:

In this article the study of the seismic response of an earth dam with sealing walls has been made by introducing the effect of the change of position and depth of the sealing wall and the effect of non-linear behavior of soil of the foundation by taking into account the variation of the viscous damping and shear modulus in each layer of soil on the seismic response of the dam. As a case study, we take the Algerian dam Kef-Eddir which lies in the far west of the territory of the Wilaya of Tipaza (wadi Eddamous), classified according to the RPA 2003 as a high seismicity zone (zone III). With a height of 71m above the foundation and a width of 478m. The seismic event applied to the rock, is the earthquake of Chenoua (29 October, 1989), with a magnitude Mw=6 that hit the region.

Keywords: earth dam, earthquake, sealing walls, viscous damping

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Authors: Khushi Chhajed

Abstract:

Context: Color has been found to have an impact on cognitive performance. Due to the negative connotation associated with red, it has been found to impair performance on intellectual tasks. Aim: This study aims to assess the effect of color on individuals' anagram solving ability. Methodology: An experimental study was conducted on 66 participants in the age group of 18–24 years. A self-made anagram assessment tool was administered. Participants were expected to solve the tool in three colors- red, blue and grey. Results: A lower score was found when presented with the color blue as compared to red. The study also found that participants took relatively greater time to solve the red colored sheet. However these results are inconsistent with pre-existing literature. Conclusion: Hence, an association between color and performance on cognitive tasks can be seen. Future directions and potential limitations are discussed.

Keywords: color psychology, experiment, anagram, performance

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Authors: Bijaya Kumar Sahoo

Abstract:

The effect of III-V nitride semiconductors on performance of a graphene-on-gold surface plasmon resonance (SPR) biosensor has been investigated theoretically. III-V nitrides (AlN, GaN and InN) have been grown between gold (Au) and graphene layers. The sensitivity and performance of the biosensor have been computed for with and without semiconductors. Due to superior electronic and optical properties, III-V nitrides demonstrate high sensitivity and performance over Si and Ge. The enhancement of evanescent electric field due to III-V nitrides have been computed and found highest for InN. The analysis shows that for a high-sensitive imaging biosensor the required optimal thickness of gold, InN and graphene are respectively 49 nm, 11 nm and 0.34 nm for the light of wavelength =633 nm (red He-Ne laser). This study suggests that InN would be a better choice for fabrication of new imaging SPR biosensors.

Keywords: SPR biosensor, optical properties, III-V nitrides, sensitivity, enhancement of electric field, performance of graphene gold SPR biosensor

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Authors: Djelloul Addad, Fatiha Belkhadem Mokhtari

Abstract:

The objective of this work is to study the retention of methylene blue (MB) by biomass. The Biomass is characterized by X-ray diffraction (XRD), infrared absorption (IRTF). Results show that the biomass contains organic and mineral substances. The effect of certain physicochemical parameters on the adsorption of MB is studied (effect of the pH). This study shows that the increase in the initial concentration of MB leads to an increase in the adsorbed quantity. The adsorption efficiency of MB decreases with increasing biomass mass. The adsorption kinetics show that the adsorption is rapid, and the maximum amount is reached after 120 min of contact time. It is noted that the pH has no great influence on the adsorption. The isotherms are best modelled by the Langmuir model. The adsorption kinetics follow the pseudo-second-order model. The thermodynamic study of adsorption shows that the adsorption is spontaneous and exothermic.

Keywords: dyes, adsorption, biomass, methylene blue, langmuir

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