Search results for: safety factor
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 8142

Search results for: safety factor

2232 Disabilities in Railways: Proposed Changes to the Design of Railway Compartments for the Inclusion of Differently Abled Persons

Authors: Bathmajaa Muralisankar

Abstract:

As much as railway station infrastructure designs and ticket-booking norms have been changed to facilitate use by differently abled persons, the railway train compartments themselves have not been made user-friendly for differently abled persons. Owing to safety concerns, dependency on others for their travel, and fear of isolation, differently abled people do not prefer travelling by train. Rather than including a dedicated compartment open only to the differently abled, including the latter with others in the normal compartment (with the proposed modifications discussed here) will make them feel secure and make for an enhanced travel experience for them. This approach also represents the most practical way to include a particular category of people in the mainstream society. Lowering the height of the compartment doors and providing a wider entrance with a ramp will provide easy entry for those using wheelchairs. As well, removing the first two alternate rows and the first two side seats will not only widen the passage and increase seating space but also improve wheelchair turning radius. This will help them travel without having to depend on others. Seating arrangements may be done to accommodate their family members near them instead of isolating the differently abled in a separate compartment. According to present ticket-booking regulations of the Indian Railways, three to four disabled persons may travel without their family or one to two along with their family, and the numbers may be added or reduced. To help visually challenged and hearing-impaired persons, in addition to the provision of special instruments, railings, and textured footpaths and flooring, the seat numbers above the seats may be set in metal or plastic as an outward projection so the visually impaired can touch and feel the numbers. Braille boards may be included at the entrance to the compartment along with seat numbers in the aforementioned projected manner. These seat numbers may be designed as buttons, which when pressed results in an announcement of the seat number in the applicable local language as well as English. Emergency buttons, rather than emergency chains, within the easy reach of disabled passengers will also help them.

Keywords: dependency, differently abled, inclusion, mainstream society

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2231 Effect of Three Desensitizers on Dentinal Tubule Occlusion and Bond Strength of Dentin Adhesives

Authors: Zou Xuan, Liu Hongchen

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The ideal dentin desensitizing agent should not only have good biological safety, simple clinical operation mode, the superior treatment effect, but also should have a durable effect to resist the oral environmental temperature change and oral mechanical abrasion, so as to achieve a persistent desensitization effect. Also, when using desensitizing agent to prevent the post-operative hypersensitivity, we should not only prevent it from affecting crowns’ retention, but must understand its effects on bond strength of dentin adhesives. There are various of desensitizers and dentin adhesives in clinical treatment. They have different chemical or physical properties. Whether the use of desensitizing agent would affect the bond strength of dentin adhesives still need further research. In this in vitro study, we built the hypersensitive dentin model and post-operative dentin model, to evaluate the sealing effects and durability on exposed tubule by three different dentin desensitizers and to evaluate the sealing effects and the bond strength of dentin adhesives after using three different dentin desensitizers on post-operative dentin. The result of this study could provide some important references for clinical use of dentin desensitizing agent. 1. As to the three desensitizers, the hypersensitive dentin model was built to evaluate their sealing effects on exposed tubule by SEM observation and dentin permeability analysis. All of them could significantly reduce the dentin permeability. 2. Test specimens of three groups treated by desensitizers were subjected to aging treatment with 5000 times thermal cycling and toothbrush abrasion, and then dentin permeability was measured to evaluate the sealing durability of these three desensitizers on exposed tubule. The sealing durability of three groups were different. 3. The post-operative dentin model was built to evaluate the sealing effects of the three desensitizers on post-operative dentin by SEM and methylene blue. All of three desensitizers could reduce the dentin permeability significantly. 4. The influences of three desensitizers on the bonding efficiency of total-etch and self-etch adhesives were evaluated with the micro-tensile bond strength study and bond interface morphology observation. The dentin bond strength for Green or group was significantly lower than the other two groups (P<0.05).

Keywords: dentin, desensitizer, dentin permeability, thermal cycling, micro-tensile bond strength

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2230 Internet Health: A Cross-Sectional Survey Exploring Identified Risks and Online Safety Measures in Parent and Children with Neurodevelopmental Disorders

Authors: Abdirahim Mohamed, Sarita Rana Chhetri, Michael Sleath, Nadia Saleem

Abstract:

Rationale: Internet usage has been very much integrated into our daily lives. Internet usage within a neurodevelopmental disorder population is also on the increase. Nevertheless, there is very little empirical research on how this population virtually protect themselves; along with how their parents can keep them safe online. This topic was an ever-growing concern to the parents within our services and in many cases would add to the stresses and mental health of parents. This ignited an idea within our team to conduct research to explore the perceived online risks within this population and how they keep themselves safe. In conjunction, we also explored how parents and caregivers monitor and safeguard their young people to the potential threats online. Our hypothesis was that the perceived risks will heavily outnumber the safeguarding measures implemented by this population. Method: Within the Coventry and Warwickshire NHS Partnership Trust Child and Adolescent Mental Health Service (CAMHS), we distributed qualitative questionnaires to all the clinical bases (N=80). Questions explored topics such as daily internet usage, safeguarding measures, and perceived threats. The researchers requested for all CAMHS clinicians to identify participants. Participants in this study were accessing CAMHS for neurodevelopmental specific interventions. Results: The data were analysed using both Excel and SPSS. Within SPSS, a MANOVA was conducted and found a significant difference between safeguarding measures and perceived online risks within responses (p ≤ 0.5). This supports our hypothesis that participants in this population are well versed in the safeguarding issues of the internet; however, struggle to implement appropriate preventative measures. Data were also screened using Excel and found that all parents and carers stated they 'monitored their child’s internet use'. Conclusion: Data suggest that parents/carers may require more specific intervention to equip them with preventative measures due to the clear discrepancy between perceived risks and safeguarding measures. More research may also need to be conducted around this area to determine appropriate methodology to explore this topic further.

Keywords: Internet, health , how safe are we , internet health check

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2229 Ultradrawing and Ultimate Tensile Properties of Ultrahigh Molecular Weight Polyethylene Composite Fibers Filled with Activated Nanocarbon Particles with Varying Specific Surface Areas

Authors: Wang-Xi Fan, Yi Ding, Zhong-Dan Tu, Kuo-Shien Huang, Chao-Ming Huang, Jen-Taut Yeh

Abstract:

Original and/or functionalized activated nanocarbon particles with a quoted specific surface area of 100, 500, 1000 and 1400 m2/g, respectively, were used to investigate the influence of specific surface areas of activated nanocarbon on ultra drawing and ultimate tensile properties of ultrahigh molecular weight polyethylene (UHMWPE), UHMWPE/activated nanocarbon and UHMWPE/ functionalized activated nanocarbon fibers. The specific surface areas of well dispersed functionalized activated nanocarbon in UHMWPE/functionalized activated nanocarbon fibers can positively affect their ultra drawing, orientation, ultimate tensile properties and “micro-fibril” characteristics. Excellent orientation and ultimate tensile properties of UHMWPE/nanofiller fibers can be prepared by ultra drawing the UHMWPE/functionalized activated nanocarbon as-prepared fibers with optimal contents and compositions of functionalized activated nanocarbon. The ultimate tensile strength value of the best prepared UHMWPE/functionalized activated nanocarbon drawn fiber reached 8.0 GPa, which was about 2.86 times of that of the best-prepared UHMWPE drawn fiber prepared in this study. Specific surface area, morphological and Fourier transform infrared analyses of original and functionalized activated nanocarbon and/or investigations of thermal, orientation factor and ultimate tensile properties of as-prepared and/or drawn UHMWPE/functionalized activated nanocarbon fibers were performed to understand the above-improved ultra drawing and ultimate tensile properties of the UHMWPE/functionalized activated nanocarbon fibers.

Keywords: activated nanocarbon, specific surface areas, ultradrawing, ultrahigh molecular weight polyethylene

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2228 Bioinformatic Approaches in Population Genetics and Phylogenetic Studies

Authors: Masoud Sheidai

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Biologists with a special field of population genetics and phylogeny have different research tasks such as populations’ genetic variability and divergence, species relatedness, the evolution of genetic and morphological characters, and identification of DNA SNPs with adaptive potential. To tackle these problems and reach a concise conclusion, they must use the proper and efficient statistical and bioinformatic methods as well as suitable genetic and morphological characteristics. In recent years application of different bioinformatic and statistical methods, which are based on various well-documented assumptions, are the proper analytical tools in the hands of researchers. The species delineation is usually carried out with the use of different clustering methods like K-means clustering based on proper distance measures according to the studied features of organisms. A well-defined species are assumed to be separated from the other taxa by molecular barcodes. The species relationships are studied by using molecular markers, which are analyzed by different analytical methods like multidimensional scaling (MDS) and principal coordinate analysis (PCoA). The species population structuring and genetic divergence are usually investigated by PCoA and PCA methods and a network diagram. These are based on bootstrapping of data. The Association of different genes and DNA sequences to ecological and geographical variables is determined by LFMM (Latent factor mixed model) and redundancy analysis (RDA), which are based on Bayesian and distance methods. Molecular and morphological differentiating characters in the studied species may be identified by linear discriminant analysis (DA) and discriminant analysis of principal components (DAPC). We shall illustrate these methods and related conclusions by giving examples from different edible and medicinal plant species.

Keywords: GWAS analysis, K-Means clustering, LFMM, multidimensional scaling, redundancy analysis

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2227 Water-Sensitive Landscaping in Desert-Located Egyptian Cities through Sheer Reductions of Turfgrass and Efficient Water Use

Authors: Sarah M. Asar, Nabeel M. Elhady

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Egypt’s current per capita water share indicates that the country suffers and has been suffering from water poverty. The abundant utilization of turfgrass in Egypt’s new urban settlements, the reliance on freshwater for irrigation, and the inadequate plant selection increase the water demand in such settlements. Decreasing the surface area of turfgrass by using alternative landscape features such as mulching, using ornamental low-maintenance plants, increasing pathways, etc., could significantly decrease the water demand of urban landscapes. The use of Ammochloa palaestina, Cenchrus crientalis (Oriental Fountain Grass), and Cistus parviflorus (with water demands of approximately 0.005m³/m²/day) as alternatives for Cynodon dactylon (0.01m³/m²/day), which is the most commonly used grass species in Egypt’s landscape, could decrease an area’s water demand by approximately 40-50%. Moreover, creating hydro-zones of similar water demanding plants would enable irrigation facilitation rather than the commonly used uniformed irrigation. Such a practice could further reduce water consumption by 15-20%. These results are based on a case-study analysis of one of Egypt’s relatively new urban settlements, Al-Rehab. Such results emphasize the importance of utilizing native, drought-tolerant vegetation in the urban landscapes of Egypt to reduce irrigation demands. Furthermore, proper implementation, monitoring, and maintenance of automated irrigation systems could be an important factor in a space’s efficient water use. As most new urban settlements in Egypt adopt sprinkler and drip irrigation systems, the lack of maintenance leads to the manual operation of such systems, and, thereby, excessive irrigation occurs.

Keywords: alternative landscape, native plants, efficient irrigation, low water demand

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2226 Factors Affecting Special Core Analysis Resistivity Parameters

Authors: Hassan Sbiga

Abstract:

Laboratory measurements methods were undertaken on core samples selected from three different fields (A, B, and C) from the Nubian Sandstone Formation of the central graben reservoirs in Libya. These measurements were conducted in order to determine the factors which affect resistivity parameters, and to investigate the effect of rock heterogeneity and wettability on these parameters. This included determining the saturation exponent (n) in the laboratory at two stages. The first stage was before wettability measurements were conducted on the samples, and the second stage was after the wettability measurements in order to find any effect on the saturation exponent. Another objective of this work was to quantify experimentally pores and porosity types (macro- and micro-porosity), which have an affect on the electrical properties, by integrating capillary pressure curves with other routine and special core analysis. These experiments were made for the first time to obtain a relation between pore size distribution and saturation exponent n. Changes were observed in the formation resistivity factor and cementation exponent due to ambient conditions and changes of overburden pressure. The cementation exponent also decreased from GHE-5 to GHE-8. Changes were also observed in the saturation exponent (n) and water saturation (Sw) before and after wettability measurement. Samples with an oil-wet tendency have higher irreducible brine saturation and higher Archie saturation exponent values than samples with an uniform water-wet surface. The experimental results indicate that there is a good relation between resistivity and pore type depending on the pore size. When oil begins to penetrate micro-pore systems in measurements of resistivity index versus brine saturation (after wettability measurement), a significant change in slope of the resistivity index relationship occurs.

Keywords: part of thesis, cementation, wettability, resistivity

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2225 Illness Perception and Health-Related Quality of Life among Young Females Living with Polycystic Ovary Syndrome

Authors: Vibha Kriti

Abstract:

Background: Polycystic ovary syndrome (PCOS) is a common endocrine disorder generally found in reproductive women. It is associated with significant reproductive, metabolic, cosmetic, and psychological consequences. Objective: There is a high prevalence of PCOS found among reproductive-age women, therefore, the major objective of the present study is to identify the illness perception of PCOS women and to explore the relationship between illness perception and health-related quality of life (HRQoL). Material and Method: A cross-sectional study was conducted in a university tertiary-care center, Sir Sunder Lal Hospital, Banaras Hindu University (B.H.U). Tools used for data collection were self-structured, which included socio-demographic status, illness perception questionnaire (revised version), and short-form 36 for assessing illness perception and health-related quality of life, respectively. Statistical analysis was done by SPSS version ‘24’. Results: The results of correlation analyses indicated that there is a strong relationship between strong illness perception and HRQoL. Stepwise regression indicated that illness identity, long illness duration, and severe consequences were associated with the worse outcome on emotional functioning and on social functioning. A high score on the controllability of the disease and seeking social support was significantly related to better functioning. Conclusion: Illness perception is an important factor in self-care behaviors in PCOS females and has a strong association with health-related quality of life and has a profound effect on it.

Keywords: polycystic ovary syndrome, illness perception, quality of life, young females, mental health

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2224 Drilling Quantification and Bioactivity of Machinable Hydroxyapatite : Yttrium phosphate Bioceramic Composite

Authors: Rupita Ghosh, Ritwik Sarkar, Sumit K. Pal, Soumitra Paul

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The use of Hydroxyapatite bioceramics as restorative implants is widely known. These materials can be manufactured by pressing and sintering route to a particular shape. However machining processes are still a basic requirement to give a near net shape to those implants for ensuring dimensional and geometrical accuracy. In this context, optimising the machining parameters is an important factor to understand the machinability of the materials and to reduce the production cost. In the present study a method has been optimized to produce true particulate drilled composite of Hydroxyapatite Yttrium Phosphate. The phosphates are used in varying ratio for a comparative study on the effect of flexural strength, hardness, machining (drilling) parameters and bioactivity.. The maximum flexural strength and hardness of the composite that could be attained are 46.07 MPa and 1.02 GPa respectively. Drilling is done with a conventional radial drilling machine aided with dynamometer with high speed steel (HSS) and solid carbide (SC) drills. The effect of variation in drilling parameters (cutting speed and feed), cutting tool, batch composition on torque, thrust force and tool wear are studied. It is observed that the thrust force and torque varies greatly with the increase in the speed, feed and yttrium phosphate content in the composite. Significant differences in the thrust and torque are noticed due to the change of the drills as well. Bioactivity study is done in simulated body fluid (SBF) upto 28 days. The growth of the bone like apatite has become denser with the increase in the number of days for all the composition of the composites and it is comparable to that of the pure hydroxyapatite.

Keywords: Bioactivity, Drilling, Hydroxyapatite, Yttrium Phosphate

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2223 Immune Complex Components Act as Agents in Relapsing Fever Borrelia Mediated Rosette Formation

Authors: Mukunda Upreti, Jill Storry, Rafael Björk, Emilie Louvet, Johan Normark, Sven Bergström

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Borrelia duttonii and most other relapsing fever species are Gram-negative bacteria which cause a blood borne infection characterized by the binding of bacterium to erythrocytes. The bacteria associate with two or more erythrocytes to form clusters of cells into rosettes. Rosetting is a major virulence factor and the mechanism is believed to facilitate persistence of bacteria in the circulatory system and the avoidance of host immune cells through masking or steric hindrance effects. However, the molecular mechanisms of rosette formation are still poorly understood. This study aims at determining the molecules involved in the rosette formation phenomenon. Fractionated serum, using different affinity purification methods, was investigated as a rosetting agent and IgG and at least one other serum components were needed for rosettes to form. An IgG titration curve demonstrated that IgG alone is not enough to restore rosette formation level to the level whole serum gives. IgG hydrolysis by IdeS ( Immunoglobulin G-degrading enzyme of Streptococcus pyogenes) and deglycosylation using N-Glycanase proved that the whole IgG molecule regardless of saccharide moieties is critical for Borrelia induced rosetting. Complement components C3 and C4 were also important serum molecules necessary to maintain optimum rosetting rates. The deactivation of complement network and serum depletion with C3 and C4 significantly reduced the rosette formation rate. The dependency of IgG and complement components also implied involvement of the complement receptor (CR1). Rosette formation test with Knops null RBC and sCR1 confirmed that CR1 is also part of Borrelia induced rosette formation.

Keywords: complement components C3 and C4, complement receptor 1, Immunoglobulin G, Knops null, Rosetting

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2222 Relationship between Physical Activity Level and Functional Movement in 16-years old Schoolchildren: A Multilevel Modelling Approach

Authors: Josip Karuc, Marjeta Mišigoj-Duraković, Goran Marković, Vedran Hadžić, Michael J. Duncan, Hrvoje Podnar, Maroje Sorić

Abstract:

As a part of the CRO-PALS longitudinal study, this investigation aimed to examine the association between different levels of physical activity (PA) and movement quality in 16-years old school children. The total number of participants in this research was 725. Movement quality was assessed via the Functional Movement Screen (FMSTM), and the PA level was estimated using the School Health Action, Planning, and Evaluation System (SHAPES) questionnaire. In addition, body fat and socioeconomic status (SES) were assessed. In order to investigate the association between total FMS score and different levels of PA, multilevel modeling was employed for boys (n=359) and girls (n=366) separately. All models were adjusted for age, body fat, and SES. Among boys, MVPA, MPA, and VPA were not significant predictors of the total FMS score (β=0.000, p=0.78; β=-0.002, p=0.455; β=0.004, p=0.158, respectively). On the contrary, among girls, VPA and MVPA showed significant effects on the total FMS score (β=0.011, p=0.001, β=0.005, p=0.006, respectively). The findings of this research provide evidence that the intensity of PA is a minor but relevant factor in describing the association between PA and movement quality in adolescent girls but not in boys. This means that the PA level does not guarantee optimal functional movement patterns. Therefore, practicing functional movement patterns in an isolated manner and at moderate to vigorous intensity could be beneficial in order to reduce the risk of injury incidence and potential orthopedic abnormalities in later life. This work was supported by the Croatian Science Foundation, grant no: IP-2016-06-9926 and grant no: DOK-2018-01-2328.

Keywords: functional movement screen, fundamental movement patterns, movement quality, pediatric

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2221 Structural Morphing on High Performance Composite Hydrofoil to Postpone Cavitation

Authors: Fatiha Mohammed Arab, Benoit Augier, Francois Deniset, Pascal Casari, Jacques Andre Astolfi

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For the top high performance foiling yachts, cavitation is often a limiting factor for take-off and top speed. This work investigates solutions to delay the onset of cavitation thanks to structural morphing. The structural morphing is based on compliant leading and trailing edge, with effect similar to flaps. It is shown here that the commonly accepted effect of flaps regarding the control of lift and drag forces can also be used to postpone the inception of cavitation. A numerical and experimental study is conducted in order to assess the effect of the geometric parameters of hydrofoil on their hydrodynamic performances and in cavitation inception. The effect of a 70% trailing edge and a 30% leading edge of NACA 0012 is investigated using Xfoil software at a constant Reynolds number 106. The simulations carried out for a range flaps deflections and various angles of attack. So, the result showed that the lift coefficient increase with the increase of flap deflection, but also with the increase of angle of attack and enlarged the bucket cavitation. To evaluate the efficiency of the Xfoil software, a 2D analysis flow over a NACA 0012 with leading and trailing edge flap was studied using Fluent software. The results of the two methods are in a good agreement. To validate the numerical approach, a passive adaptive composite model is built and tested in the hydrodynamic tunnel at the Research Institute of French Naval Academy. The model shows the ability to simulate the effect of flap by a LE and TE structural morphing due to hydrodynamic loading.

Keywords: cavitation, flaps, hydrofoil, panel method, xfoil

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2220 Modeling Depth Averaged Velocity and Boundary Shear Stress Distributions

Authors: Ebissa Gadissa Kedir, C. S. P. Ojha, K. S. Hari Prasad

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In the present study, the depth-averaged velocity and boundary shear stress in non-prismatic compound channels with three different converging floodplain angles ranging from 1.43ᶱ to 7.59ᶱ have been studied. The analytical solutions were derived by considering acting forces on the channel beds and walls. In the present study, five key parameters, i.e., non-dimensional coefficient, secondary flow term, secondary flow coefficient, friction factor, and dimensionless eddy viscosity, were considered and discussed. An expression for non-dimensional coefficient and integration constants was derived based on the boundary conditions. The model was applied to different data sets of the present experiments and experiments from other sources, respectively, to examine and analyse the influence of floodplain converging angles on depth-averaged velocity and boundary shear stress distributions. The results show that the non-dimensional parameter plays important in portraying the variation of depth-averaged velocity and boundary shear stress distributions with different floodplain converging angles. Thus, the variation of the non-dimensional coefficient needs attention since it affects the secondary flow term and secondary flow coefficient in both the main channel and floodplains. The analysis shows that the depth-averaged velocities are sensitive to a shear stress-dependent model parameter non-dimensional coefficient, and the analytical solutions are well agreed with experimental data when five parameters are included. It is inferred that the developed model may facilitate the interest of others in complex flow modeling.

Keywords: depth-average velocity, converging floodplain angles, non-dimensional coefficient, non-prismatic compound channels

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2219 Teachers' Mental Health: Perceived Social Justice and Life Satisfaction

Authors: Yan Li, Qi-Fan Jia, Jie Zhou

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In today’s China, primary and secondary teachers are living a hard life with high pressure but low payment, which results in a sense of unfair and less satisfaction of life. However, teachers’ life satisfaction is a significant factor of their mental health and plays an important role in the development and progress of the society. This study was aimed to explore the effect of teachers’ perception of social justice on life satisfaction. 450 primary and secondary teachers from China were measured with life satisfaction scales, social justice scales, income satisfaction scale, job satisfaction scale, pressure condition scale, and major life event scale. Results showed their pressure is significantly higher than average, while life satisfaction, job satisfaction, income satisfaction and perceived social justice are lower. Hierarchical regression analysis showed that demographic variables, i.e., gender, age, education level and matric status, and factors related to occupation, i.e., professional title, school type and working hours per day cannot predict teachers’ life satisfaction. Teachers who had worked for 11-20 years had a lower life satisfaction compared to those with 1-5 years working experience. However, social status, monthly household income, income satisfaction, as well as job satisfaction were positively related to life satisfaction, whereas pressure condition was negatively related to it. After controlling for demographic factors and individual attitudes, social justice still had a positive effect on life satisfaction, among which distributive justice played a more important role than procedural justice. The suggestions on teachers’ condition in China and the implications for education reform to improve teachers’ mental health are discussed.

Keywords: life satisfaction, mental health, primary and secondary teachers, social justice

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2218 Removal of Polycyclic Aromatic Hydrocarbons (PAHS) and the Response of Indigenous Bacteria in Highly Contaminated Aged Soil after Persulfate Oxidation

Authors: Yaling Gou, Sucai Yang, Pengwei Qiao

Abstract:

Integrated chemical-biological treatment is an attractive alternative to remove polycyclic aromatic hydrocarbons (PAHs) from contaminated soil; wherein indigenous bacteria is the key factor for the biodegradation of residual PAHs concentrations after the application of chemical oxidation. However, the systematical study on the impact of persulfate (PS) oxidation on indigenous bacteria as well as PAHs removal is still scarce. In this study, the influences of different PS dosages (1%, 3%, 6%, and 10% [w/w]), as well as various activation methods (native iron, H2O2, alkaline, ferrous iron, and heat) on PAHs removal and indigenous bacteria in highly contaminated aged soil were investigated. Apparent degradation of PAHs in the soil treated with PS oxidation was observed, and the removal efficiency of total PAHs in the soil ranged from 38.28% to 79.97%. The removal efficiency of total PAHs in the soil increased with increasing consumption of PS. However, the bacterial abundance in soil was negatively affected following oxidation for all of the treatments added with PS, with bacterial abundance in the soil decreased by 0.89~2.88 orders of magnitude compared to the untreated soil. Moreover, the number of total bacteria in the soil decreased as PS consumption increased. Different PS activation methods and PS dosages exhibited different influences on the bacterial community composition. Bacteria capable of degrading PAHs under anoxic conditions were composed predominantly by Proteobacteria and Firmicutes. The total amount of Proteobacteria and Firmicutes also decreased with increasing consumption of PS. The results of this study provide important insight into the design of PAHs contaminated soil remediation projects.

Keywords: activation method, chemical oxidation, indigenous bacteria, polycyclic aromatic hydrocarbon

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2217 Absorption and Carrier Transport Properties of Doped Hematite

Authors: Adebisi Moruf Ademola

Abstract:

Hematite (Fe2O3),commonly known as ‘rust’ which usually surfaced on metal when exposed to some climatic materials. This emerges as a promising candidate for photoelectrochemical (PEC) water splitting due to its favorable physiochemical properties of the narrow band gap (2.1–2.2 eV), chemical stability, nontoxicity, abundance, and low cost. However, inherent limitations such as short hole diffusion length (2–4 nm), high charge recombination rate, and slow oxygen evolution reaction kinetics inhibit the PEC performances of a-Fe2O3 photoanodes. As such, given the narrow bandgap enabling excellent optical absorption, increased charge carrier density and accelerated surface oxidation reaction kinetics become the key points for improved photoelectrochemical performances for a-Fe2O3 photoanodes and metal ion doping as an effective way to promote charge transfer by increasing donor density and improving the electronic conductivity of a-Fe2O3. Hematite attracts enormous efforts with a number of metal ions (Ti, Zr, Sn, Pt ,etc.) as dopants. A facile deposition-annealing process showed greatly enhanced PEC performance due to the increased donor density and reduced electron-hole recombination at the time scale beyond a few picoseconds. Zr doping was also found to enhance the PEC performance of a-Fe2O3 nanorod arrays by reducing the rate of electron-hole recombination. Slow water oxidation reaction kinetics, another main factor limiting the PEC water splitting efficiency of aFe2O3 as photoanodes, was previously found to be effectively improved by surface treatment.

Keywords: deposition-annealing, hematite, metal ion doping, nanorod

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2216 Assessment of Attractency of Bactrocera Zonata and Bactrocera dorsalis (Diptera:Tephritidae) to Different Biolure Phagostimulant-Mixtures

Authors: Muhammad Dildar Gogi, Muhammad Jalal Arif, Muhammad Junaid Nisar, Mubashir Iqbal, Waleed Afzal Naveed, Muhammad Ahsan Khan, Ahmad Nawaz, Muhammad Sufian, Muhammad Arshad, Amna Jalal

Abstract:

Fruit flies of Bactrocera genus cause heavy losses in fruits and vegetables globally and insecticide-application for their control creates issues of ecological backlash, environmental pollution, and food safety. There is need to explore alternatives and food-baits application is considered safe for the environment and effective for fruit fly management. Present experiment was carried out to assess the attractancy of five phagostimulant-Mixtures (PHS-Mix) prepared by mixing banana-squash, mulberry, protein-hydrolysate and molasses with some phagostimulant-lure sources including beef extract, fish extract, yeast, starch, rose oil, casein and cedar oil in five different ratios i.e., PHS-Mix-1 (1 part of all ingredients), PHS-Mix-2 (1 part of banana with 0.75 parts of all other ingredients), PHS-Mix-3 (1 part of banana with 0.5 parts of all other ingredients), PHS-Mix-4 (1 part of banana with 0.25 parts of all other ingredients) and PHS-Mix-5 (1 part of banana with 0.125 parts of all other ingredients). These were evaluated in comparison with a standard (GF-120). PHS-Mix-4 demonstrated 40.5±1.3-46.2±1.6% AI for satiated flies (class-II i.e., moderately attractive) and 59.5±2.0-68.6±3.0% AI for starved flies (class-III i.e., highly attractive) for both B. dorsalis and B. zonata in olfactometric study while the same exhibited 51.2±0.53% AI (class-III i.e., highly attractive) for B. zonata and 45.4±0.89% AI (class-II i.e., moderately attractive) for B. dorsalis in field study. PHS-Mix-1 proved non-attractive (class-I) and moderately attractive (class-II) phagostimulant in olfactometer and field studies, respectively. PHS-Mix-2 exhibited moderate attractiveness for starved lots in olfactometer and field-lot in field studies. PHS-Mix-5 proved non-attractive to starved and satiated lots of B. zonata and B. dorsalis females in olfactometer and field studies. Overall PHS-Mix-4 proved better phagostimulant-mixture followed by PHS-Mix-3 which was categorized as class-II (moderately attractive) phagostimulant for starved and satiated lots of female flies of both species in olfactometer and field studies; hence these can be exploited for fruit fly management.

Keywords: attractive index, field conditions, olfactometer, Tephritid flies

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2215 Challenges of Sustainable Development of Small and Medium-Sized Enterprises in Georgia

Authors: Kharaishvili Eteri

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The article highlights the importance of small and medium-sized enterprises in achieving the goals of sustainable development of the economy and increasing the well-being of the population. The opinion is put forward that it is necessary to adapt the activities of small and medium-sized firms in Georgia to sustainable business models. Therefore, it is important to identify the challenges that will ensure compliance with the goals and requirements of sustainable development of small and mediumsized enterprises. Objectives. The goal of the study is to reveal the challenges of sustainable development in small and medium-sized enterprises in Georgia and to develop recommendations for strategic development opportunities. Methodologies The challenges of sustainable development of small and medium-sized enterprises are investigated with the following methodology: bibliographic research of scientific works and reports of organizations is carried out; Based on the grouping of sustainable development goals, the performance indicators of these goals are studied; Differences with respect to the corresponding indicators of European countries are determined by the comparison method; The matrix scheme establishes the conditions and tools for sustainable development; Challenges of sustainable development are identified by factor analysis. Contributions Trends in the sustainable development of small and medium-sized enterprises are studied from the point of view of economic, social and environmental factors; To ensure sustainability, the conditions and tools for sustainable development are established (certified supply chains and global markets, allocation of financial resources necessary for sustainable development, proper public procurement, highly qualified workforce, etc.); Several main challenges have been identified in the sustainable development of small and medium-sized enterprises, including: limited internal resources; Institutional factors, especially vague and imperfect regulations, bureaucracy; low level of investments; Low level of qualification of human capital and others.

Keywords: small and medium-sized enterprises, sustainable development, conditions of sustainable development, strategic directions of sustainable development.

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2214 A Comparative Study of Public and Private School Adolescent Girls on the Issues of Menstrual Hygiene and the Management Issues

Authors: Ashok Pandey, Rajan Adhikari

Abstract:

Introduction: Menstruation is part of the female reproductive cycle that starts when girls become sexually mature at the time of puberty. It is a phenomenon unique to the females. During a menstrual period, a woman bleeds from her uterus via the vagina. For decades, in many countries, academic school ‘type,’ private or public, as a predictor of or factor in future academic success has been researched and debated. MATERIAL AND METHODS: The comparative study was carried out with adolescent girls studying in both public and private schools of Kathmandu valley. A total of 100 girls participated in the survey, and out of them 21 participated in the FGD and 5 in the in- depth interview. Quantitative data from the survey was analyzed using SPSS 16.0 software. Informed verbal consent with the respective head of school and the respondents were taken before data collection. Results:The age of the respondents ranges from 11 to 18 years, with mean age of menarche being 12.37 years in both school adolescent girls. 70 percent of the public school adolescent girls and 72 percent of the private school adolescent girls are feeling upset and tension during menarche. There is a statistically significant difference on take rest during the period and good hygienic practice during menstruation of public/private school, at α=0. 05 level of significance. There is a statistically significant difference on overall score of practice during menstruation between public and private adolescent girls. Conclusion: Private schools children are more knowledgeable and maintain hygiene as compere to public school even though, it can be said that among the adolescent school girls both in public and private school, menstrual knowledge and perceptions are poor and practices often not optimal for proper hygiene. Often ignored issues of privacy affect the hygienic practices and daily lives.

Keywords: Comparison, Menstruation, Private school, Public School

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2213 Enhanced Acquisition Time of a Quantum Holography Scheme within a Nonlinear Interferometer

Authors: Sergio Tovar-Pérez, Sebastian Töpfer, Markus Gräfe

Abstract:

The work proposes a technique that decreases the detection acquisition time of quantum holography schemes down to one-third; this allows the possibility to image moving objects. Since its invention, quantum holography with undetected photon schemes has gained interest in the scientific community. This is mainly due to its ability to tailor the detected wavelengths according to the needs of the scheme implementation. Yet this wavelength flexibility grants the scheme a wide range of possible applications; an important matter was yet to be addressed. Since the scheme uses digital phase-shifting techniques to retrieve the information of the object out of the interference pattern, it is necessary to acquire a set of at least four images of the interference pattern along with well-defined phase steps to recover the full object information. Hence, the imaging method requires larger acquisition times to produce well-resolved images. As a consequence, the measurement of moving objects remains out of the reach of the imaging scheme. This work presents the use and implementation of a spatial light modulator along with a digital holographic technique called quasi-parallel phase-shifting. This technique uses the spatial light modulator to build a structured phase image consisting of a chessboard pattern containing the different phase steps for digitally calculating the object information. Depending on the reduction in the number of needed frames, the acquisition time reduces by a significant factor. This technique opens the door to the implementation of the scheme for moving objects. In particular, the application of this scheme in imaging alive specimens comes one step closer.

Keywords: quasi-parallel phase shifting, quantum imaging, quantum holography, quantum metrology

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2212 Means of Securing Graves in the Egyptian Kingdom Era

Authors: Mohamed Ahmed Madkour, Haitham Magdy Hamad

Abstract:

This research aims to study the means of securing graves in the Egyptian kingdom era, and revolves around many basic ideas used by the ancient Egyptian to protect his graves from thieves, which included architectural characteristics, which gave it importance only others. The most important of which was the choice of the place of the grave, which chose a kohl place in the desert to protect the graves, which is the valley of kings, and whether the choice of that place had an impact in protecting the grave or not, in addition to other elements followed in the architectural planning, which was in the valley of kings. The multiplicity of the tomb, the construction of the well chamber to deceive the thieves by the end of the graves suddenly, the construction of the wells of the tombs, which contained the burial chamber at the bottom of the main well and the effect of all these factors on the graves, and this shows the importance of the graves to the ancient Egyptian and his belief in resurrection and immortality. The Egyptian resorted to the elements of protection and was a religious worker by The protector gods and special texts to protect the deceased from any danger to protect the tomb. As for the human factor of securing the tomb through human guards (police) and security teams based on the guard and the words indicating the protection and the guard teams and the teams of the majai. The most important developments that arose on the cemetery from Tamit entrance, corridors, chambers, burial chamber and coffin, and the use of sand to close the well after from one cemetery to another and from time to time where it was built in the late period inside the temple campus to be under the attention of the priests and their protection, as the study dealt with an analytical study For the means of securing graves in the Egyptian kingdom period.

Keywords: archaeology, Egyptian kingdom era, graves, tombs, ancient Egyptian

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2211 Computational Methods in Official Statistics with an Example on Calculating and Predicting Diabetes Mellitus [DM] Prevalence in Different Age Groups within Australia in Future Years, in Light of the Aging Population

Authors: D. Hilton

Abstract:

An analysis of the Australian Diabetes Screening Study estimated undiagnosed diabetes mellitus [DM] prevalence in a high risk general practice based cohort. DM prevalence varied from 9.4% to 18.1% depending upon the diagnostic criteria utilised with age being a highly significant risk factor. Utilising the gold standard oral glucose tolerance test, the prevalence of DM was 22-23% in those aged >= 70 years and <15% in those aged 40-59 years. Opportunistic screening in Australian general practice potentially can identify many persons with undiagnosed type 2 DM. An Australian Bureau of Statistics document published three years ago, reported the highest rate of DM in men aged 65-74 years [19%] whereas the rate for women was highest in those over 75 years [13%]. If you consider that the Australian Bureau of Statistics report in 2007 found that 13% of the population was over 65 years of age and that this will increase to 23-25% by 2056 with a further projected increase to 25-28% by 2101, obviously this information has to be factored into the equation when age related diabetes prevalence predictions are calculated. This 10-15% proportional increase of elderly persons within the population demographics has dramatic implications for the estimated number of elderly persons with DM in these age groupings. Computational methodology showing the age related demographic changes reported in these official statistical documents will be done showing estimates for 2056 and 2101 for different age groups. This has relevance for future diabetes prevalence rates and shows that along with many countries worldwide Australia is facing an increasing pandemic. In contrast Japan is expected to have a decrease in the next twenty years in the number of persons with diabetes.

Keywords: epidemiological methods, aging, prevalence, diabetes mellitus

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2210 Stakeholders Views on Why Childhood Obesity is Rising in Lagos, Nigeria

Authors: A. A. Adedini, B. A. Aina, P. U. Ogbo

Abstract:

Child obesity is on the rise globally. According to the World Health Organization, the number of obese children would increase to 70 million by 2025 if no intervention is made. An increase in the prevalence of overweight and obesity amongst school children in Lagos State, Nigeria has been established but specific factors promoting its prevalence are unknown. This aim of this study is to identify the commonly expressed factor(s) responsible for the rise in prevalence of child overweight and obesity in Lagos, Nigeria. Five focus group discussions were conducted with different groups of stake-holders involved in child care, namely: parents, teachers and health workers. Participants were recruited using a purposive sampling method; a validated question guide was employed for the discussion sessions. The discussions were recorded, collated, analysed using Grounded theory to extract themes. Six themes emerged from the discussions as follows: Civilization and lifestyle imbalance resulting from busy work schedules of young mothers leading to adoption of westernized culture promoting preference for processed and fast food meals; insecurity and congestion of the state which discourages out-door activities; ignorance of the populace on the prevalence of child obesity in the state; inadequate educative and enlightenment programmes in schools and by the Nigerian government; myths on child care and body physique and societal perceptions of the children born into affluent homes. Some of the factors responsible for the rise in the prevalence of child obesity in Lagos, Nigeria have been identified. Preventive strategies to control the prevalence of obesity in children residing in Lagos state is considered for further studies.

Keywords: Childhood Obesity, factors, lagos state, stakeholders

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2209 Development of Alpha Spectroscopy Method with Solid State Nuclear Track Detector Using Aluminium Thin Films

Authors: Nidal Dwaikat

Abstract:

This work presents the development of alpha spectroscopy method with Solid-state nuclear track detectors using aluminum thin films. The resolution of this method is high, and it is able to discriminate between alpha particles at different incident energy. It can measure the exact number of alpha particles at specific energy without needing a calibration of alpha track diameter versus alpha energy. This method was tested by using Cf-252 alpha standard source at energies 5.11 Mev, 3.86 MeV and 2.7 MeV, which produced by the variation of detector -standard source distance. On front side, two detectors were covered with two Aluminum thin films and the third detector was kept uncovered. The thickness of Aluminum thin films was selected carefully (using SRIM 2013) such that one of the films will block the lower two alpha particles (3.86 MeV and 2.7 MeV) and the alpha particles at higher energy (5.11 Mev) can penetrate the film and reach the detector’s surface. The second thin film will block alpha particles at lower energy of 2.7 MeV and allow alpha particles at higher two energies (5.11 Mev and 3.86 MeV) to penetrate and produce tracks. For uncovered detector, alpha particles at three different energies can produce tracks on it. For quality assurance and accuracy, the detectors were mounted on thick enough copper substrates to block exposure from the backside. The tracks on the first detector are due to alpha particles at energy of 5.11 MeV. The difference between the tracks number on the first detector and the tracks number on the second detector is due to alpha particles at energy of 3.8 MeV. Finally, by subtracting the tracks number on the second detector from the tracks number on the third detector (uncovered), we can find the tracks number due to alpha particles at energy 2.7 MeV. After knowing the efficiency calibration factor, we can exactly calculate the activity of standard source.

Keywords: aluminium thin film, alpha particles, copper substrate, CR-39 detector

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2208 A Structured Mechanism for Identifying Political Influencers on Social Media Platforms: Top 10 Saudi Political Twitter Users

Authors: Ahmad Alsolami, Darren Mundy, Manuel Hernandez-Perez

Abstract:

Social media networks, such as Twitter, offer the perfect opportunity to either positively or negatively affect political attitudes on large audiences. The existence of influential users who have developed a reputation for their knowledge and experience of specific topics is a major factor contributing to this impact. Therefore, knowledge of the mechanisms to identify influential users on social media is vital for understanding their effect on their audience. The concept of the influential user is related to the concept of opinion leaders' to indicate that ideas first flow from mass media to opinion leaders and then to the rest of the population. Hence, the objective of this research was to provide reliable and accurate structural mechanisms to identify influential users, which could be applied to different platforms, places, and subjects. Twitter was selected as the platform of interest, and Saudi Arabia as the context for the investigation. These were selected because Saudi Arabia has a large number of Twitter users, some of whom are considerably active in setting agendas and disseminating ideas. The study considered the scientific methods that have been used to identify public opinion leaders before, utilizing metrics software on Twitter. The key findings propose multiple novel metrics to compare Twitter influencers, including the number of followers, social authority and the use of political hashtags, and four secondary filtering measures. Thus, using ratio and percentage calculations to classify the most influential users, Twitter accounts were filtered, analyzed and included. The structured approach is used as a mechanism to explore the top ten influencers on Twitter from the political domain in Saudi Arabia.

Keywords: Twitter, influencers, structured mechanism, Saudi Arabia

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2207 Valorization of a Forest Waste, Modified P-Brutia Cones, by Biosorption of Methyl Geen

Authors: Derradji Chebli, Abdallah Bouguettoucha, Abdelbaki Reffas Khalil Guediri, Abdeltif Amrane

Abstract:

The removal of Methyl Green dye (MG) from aqueous solutions using modified P-brutia cones (PBH and PBN), has been investigated work. The physical parameters such as pH, temperature, initial MG concentration, ionic strength are examined in batch experiments on the sorption of the dye. Adsorption removal of MG was conducted at natural pH 4.5 because the dye is only stable in the range of pH 3.8 to 5. It was observed in experiments that the P-brutia cones treated with NaOH (PBN) exhibited high affinity and adsorption capacity compared to the MG P-brutia cones treated with HCl (PBH) and biosorption capacity of modified P-brutia cones (PBN and PBH) was enhanced by increasing the temperature. This is confirmed by the thermodynamic parameters (ΔG° and ΔH°) which show that the adsorption of MG was spontaneous and endothermic in nature. The positive values of ΔS° suggested an irregular increase in the randomness for both adsorbent (PBN and PBH) during the adsorption process. The kinetic model pseudo-first order, pseudo-second order, and intraparticle diffusion coefficient were examined to analyze the sorption process; they showed that the pseudo-second-order model is the one that best describes the adsorption process (MG) on PBN and PBH with a correlation coefficient R²> 0.999. The ionic strength has shown that it has a negative impact on the adsorption of MG on two supports. A reduction of 68.5% of the adsorption capacity for a value Ce=30 mg/L was found for the PBH, while the PBN did not show a significant influence of the ionic strength on adsorption especially in the presence of NaCl. Among the tested isotherm models, the Langmuir isotherm was found to be the most relevant to describe MG sorption onto modified P-brutia cones with a correlation factor R²>0.999. The capacity adsorption of P-brutia cones, was confirmed for the removal of a dye, MG, from aqueous solution. We note also that P-brutia cones is a material very available in the forest and low-cost biomaterial

Keywords: adsorption, p-brutia cones, forest wastes, dyes, isotherm

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2206 Financing Innovation: Differences across National Innovation Systems

Authors: Núria Arimany Serrat, Xavier Ferràs Hernández, Petra A. Nylund, Eric Viardot

Abstract:

Innovation is an increasingly important antecedent to firm competitiveness and growth. Successful innovation, however, requires a significant financial commitment and the means of financing accessible to the firm may affect its ability to innovate. The access to equity financing such as venture capital has been connected to innovativeness for young firms. For established enterprises, debt financing of innovation may be a more realistic option. Continuous innovation and growth would otherwise require a constant increase of equity. We, therefore, investigate the relation between debt financing and innovation for large firms and hypothesize that those firms that carry more debt will be more innovative. The need for debt financing of innovation may be reduced for very profitable firms, which can finance innovation with cash flow. We thus hypothesize a moderating effect of profitability on the relationship between debt financing and innovation. We carry out an empirical investigation using a longitudinal data set including 167 large European firms over five years, resulting in 835 firm years. We apply generalized least squares (GLS) regression with fixed firm effects to control for firm heterogeneity. The findings support our hypotheses and we conclude that access to debt finding is an important antecedent of innovation, with profitability as a moderating factor. The results do however differ across national innovation systems and we find a strong relationship for British, Dutch, French, and Italian firms but not for German and Spanish entities. We discuss differences in the national systems of innovation and financing which contextualize the variations in the findings and thus make a nuanced contribution to the research in innovation financing. The cross-country differences calls for differentiated advice to managers, institutions, and researchers depending on the national context.

Keywords: innovation, R&D, national innovation systems, financing

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2205 The Study of Tourism Destination Management Factors for Sustainable Tourism: Case Study of Haikou, Hainan Province

Authors: Jiaying Gao, Thammananya Sakcharoen, Wilailuk Niyommaneerat

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Haikou is the capital of Hainan, a major tourism province in China with rich ecotourism resources. There is a need to strengthen tourism destination management in Haikou toward sustainable development as a tourism city. The purpose of this study was to investigate the relationship between tourism destination management and sustainable tourism in Haikou. Exploratory factor analysis was used to extract six dimensions of this study. Three dimensions (10 factors) of tourism destination management were analyzed in terms of economic development, social and cultural development, and conservation of ecosystem. Sustainability awareness, tourism development experience, and tourism public infrastructure in three dimensions (12 factors) of sustainable tourism. There were 426 questionnaire respondents, including 225 tourists, 172 residents, 12 tourism agency persons, 10 government persons, 3 self-employed, and 4 others. The Structural equation modeling (SEM) model was finally conducted to test the hypotheses empirically and explore the impact relationship. The study found a significant relationship between tourism destination management and sustainable tourism: social and cultural development had the greatest significant positive impact on the tourism development experience (0.788***). Social and cultural development also showed a significant positive impact and great impetus on tourism public infrastructure (0.561***). A negative effect relationship (-0.096***) emerged between ecosystem conversion and tourism development experience. It showed a positive relationship between economic development and social and cultural development of tourism destination management in promoting sustainable tourism. There are still some gaps for improvement, such as the need for sustainable ecological management to promote local sustainable tourism trends and enhance tourism experience development, which may require a long-term process of mitigation.

Keywords: Haikou (Hainan, China), influence relationship, sustainable tourism, tourism destination management

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2204 Ergonomic Adaptations in Visually Impaired Workers - A Literature Review

Authors: Kamila Troper, Pedro Mestre, Maria Lurdes Menano, Joana Mendonça, Maria João Costa, Sandra Demel

Abstract:

Introduction: Visual impairment is a problem that has an influence on hundreds of thousands of people all over the world. Although it is possible for a Visually Impaired person to do most jobs, the right training, technological assistance, and emotional support are essential. Ergonomics be able to solve many of the problems/issues with the relative ease of positioning, lighting and design of the workplace. A little forethought can make a tremendous difference to the ease with which a person with an impairment function. Objectives: Review the main ergonomic adaptation measures reported in the literature in order to promote better working conditions and safety measures for the visually impaired. Methodology: This was an exploratory-descriptive, qualitative literature systematic review study. The main databases used were: PubMed, BIREME, LILACS, with articles and studies published between 2000 and 2021. Results: Based on the principles of the theoretical references of ergonomic analysis of work, the main restructuring of the physical space of the workstations were: Accessibility facilities and assistive technologies; A screen reader that captures information from a computer and sends it in real-time to a speech synthesizer or Braille terminal; Installations of software with voice recognition, Monitors with enlarged screens; Magnification software; Adequate lighting, magnifying lenses in addition to recommendations regarding signage and clearance of the places where the visually impaired pass through. Conclusions: Employability rates for people with visual impairments(both those who are blind and those who have low vision)are low and continue to be a concern to the world and for researchers as a topic of international interest. Although numerous authors have identified barriers to employment and proposed strategies to remediate or circumvent those barriers, people with visual impairments continue to experience high rates of unemployment.

Keywords: ergonomic adaptations, visual impairments, ergonomic analysis of work, systematic review

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2203 Microscopic and Mesoscopic Deformation Behaviors of Mg-2Gd Alloy with or without Li Addition

Authors: Jing Li, Li Jin, Fulin Wang, Jie Dong, Wenjiang Ding

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Mg-Li dual-phase alloy exhibits better combination of yield strength and elongation than the Mg single-phase alloy. To exploit its deformation behavior, the deformation mechanisms of Mg-2Gd alloy with or without Li addition, i.e., Mg-6Li-2Gd and Mg-2Gd alloy, have been studied at both microscale and mesoscale. EBSD-assisted slip trace, twin trace, and texture evolution analysis show that the α-Mg phase of Mg-6Li-2Gd alloy exhibits different microscopic deformation mechanisms with the Mg-2Gd alloy, i.e., mainly prismatic slip in the former one, while basal slip, prismatic slip and extension twin in the latter one. Further Schmid factor analysis results attribute this different intra-phase deformation mechanisms to the higher critical resolved shear stress (CRSS) value of extension twin and lower ratio of CRSSprismatic /CRSSbasal in the α-Mg phase of Mg-6Li-2Gd alloy. Additionally, Li addition can induce dual-phase microstructure in the Mg-6Li-2Gd alloy, leading to the formation of hetero-deformation induced (HDI) stress at the mesoscale. This can be evidenced by the hysteresis loops appearing during the loading-unloading-reloading (LUR) tensile tests and the activation of multiple slip activity in the α-Mg phase neighboring β-Li phase. The Mg-6Li-2Gd alloy shows higher yield strength is due to the harder α-Mg phase arising from solid solution hardening of Li addition, as well asthe strengthening of soft β-Li phase by the HDI stress during yield stage. Since the strain hardening rate of Mg-6Li-2Gd alloy is lower than that of Mg-2Gd alloy after ~2% strain, which is partly due to the weak contribution of HDI stress, Mg-6Li-2Gd alloy shows no obvious increase of uniform elongation than the Mg-2Gd alloy.But since the β-Li phase is effective in blunting the crack tips, the Mg-6Li-2Gd alloy shows ununiform elongation, which, thus, leads to the higher total elongation than the Mg-2Gd alloy.

Keywords: Mg-Li-Gd dual-phase alloy, phase boundary, HDI stress, dislocation slip activity, mechanical properties

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