Search results for: diffusion effect

Authors: Yonguk L. Park, Jeonghoon Seol

Abstract:

The Republic of Korea is facing a special situation as it is the only divided country in the world. Even though Korea is facing such unstable circumstances in terms of a foreign diplomacy situation, Korea is one of the countries who, in concern for world peace, have been sending troops overseas. The troops spend more than a year at sea and may suffer from different types of psychological disorders. The purpose of this study is to try to find factors that promote psychological well-being of troops and improve their psychological health. We investigated the effect of dispatch sailors’ occupational calling and social support on anxiety before they are sent overseas and also examined the interaction between occupational calling and social support on anxiety. One hundred thirty-eight dispatched sailors participated in this study, wherein they completed the Korean calling scale, multifaceted social support scale, and anxiety scale –Y form. We analyzed the data using hierarchical regression. The results showed that after controlling gender, marital status, and the previous experiences of dispatch, those who have a higher level of occupational calling and perceived social support experienced a low level of anxiety before they are sent (β = -.276, β = -.395). Furthermore, we examined the interaction effect. If the troops’ perceived social support is high, they experience a low level of anxiety—even if they have a low level of occupational calling. This study confirms that both occupational calling and social support reduce the level of anxiety of the troops. The research provides meaningful information in understanding those who serve in the Navy’s distinctive situations and contributes to improving their psychological well-being. We suggest that sailors undergo training to have a higher occupational calling and healthy relationships with friends, families, and co-workers who provide emotional and social support.

Keywords: navy, occupational calling, social support, anxiety

Procedia PDF Downloads 251

Authors: Claire Stafford, Charles Golden, Daniel Amen, Kristen Willeumier

Abstract:

The aim of this study is to investigate the effect of the administration of the Conners Continuous Performance Test (CPT-3) on cerebral blood flow (CBF) in adults with ADHD. The data for this study was derived from a large SPECT database. Participants in the ADHD group (n=81, Mage=37.97) were similar to those in the healthy control group (n=8503, Mage=41.86). All participants were assessed for cerebral blood flow levels before and after CPT-3 administration. Both age and gender were considered covariates. Multiple 2-by-2 ANCOVAs with repeated measures were conducted with sphericity assumed. The main effects of CPT-3 administration on CBF levels were significant in the left and right side of the frontal and occipital, and right temporal lobe. The main effects of ADHD diagnosis were significant in all brain areas assessed. The interaction between CPT-3 administration and ADHD diagnosis was significant in the left and right side of the limbic system, basal ganglia, the frontal lobe, and occipital lobe. Post hoc tests with a Bonferroni adjustment revealed that CBF levels increased following CPT-3 administration but less so in the ADHD group. Individuals had higher levels of CBF following the administration of CPT-3. Due to a significant interaction, we can infer that ADHD diagnosis changes the effect of CPT-3 administration on CBF levels. This is consistent with our hypothesis considering that CPT-3 is a test of sustained attention, a common challenge for children with ADHD. The aforementioned interaction was not found to be significant in the parietal lobe. This may be due to the nature of CPT- 3 which does not require an integration of sensory information.

Keywords: SPECT, ADHD, conners continuous performance test, cerebral blood flow

Procedia PDF Downloads 94

Authors: Estela Díaz

Abstract:

This article aims to make three contributions. First, build on the literature on ethical decision-making literature by exploring factors that influence the intention of adopting veganism. Second, study the superiority of extended models of the Theory of Planned Behavior (TPB) for understanding the process involved in forming the intention of adopting veganism. Third, analyze the moderating effect of gender on TPB given that attitudes and behavior towards animals are gender-sensitive. No study, to our knowledge, has examined these questions. Veganism is not a diet but a political and moral stand that exclude, for moral reasons, the use of animals. Although there is a growing interest in studying veganism, it continues being overlooked in empirical research, especially within the domain of social psychology. TPB has been widely used to study a broad range of human behaviors, including moral issues. Nonetheless, TPB has rarely been applied to examine ethical decisions about animals and, even less, to veganism. Hence, the validity of TPB in predicting the intention of adopting veganism remains unanswered. A total of 476 non-vegan Spanish university students (55.6% female; the mean age was 23.26 years, SD= 6.1) responded to online and pencil-and-paper self-reported questionnaire based on previous studies. TPB extended models incorporated two background factors: ‘general attitudes towards humanlike-attributes ascribed to animals’ (AHA) (capacity for reason/emotions/suffer, moral consideration, and affect-towards-animals); and ‘general attitudes towards 11 uses of animals’ (AUA). SPSS 22 and SmartPLS 3.0 were used for statistical analyses. This study constructed a second-order reflective-formative model and took the multi-group analysis (MGA) approach to study gender effects. Six models of TPB (the standard and five competing) were tested. No a priori hypotheses were formulated. The results gave partial support to TPB. Attitudes (ATTV) (β = .207, p < .001), subjective norms (SNV) (β = .323, p < .001), and perceived control behavior (PCB) (β = .149, p < .001) had a significant direct effect on intentions (INTV). This model accounted for 27,9% of the variance in intention (R2Adj = .275) and had a small predictive relevance (Q2 = .261). However, findings from this study reveal that contrary to what TPB generally proposes, the effect of the background factors on intentions was not fully mediated by the proximal constructs of intentions. For instance, in the final model (Model#6), both factors had significant multiple indirect effect on INTV (β = .074, 95% C = .030, .126 [AHA:INTV]; β = .101, 95% C = .055, .155 [AUA:INTV]) and significant direct effect on INTV (β = .175, p < .001 [AHA:INTV]; β = .100, p = .003 [AUA:INTV]). Furthermore, the addition of direct paths from background factors to intentions improved the explained variance in intention (R2 = .324; R2Adj = .317) and the predictive relevance (Q2 = .300) over the base-model. This supports existing literature on the superiority of enhanced TPB models to predict ethical issues; which suggests that moral behavior may add additional complexity to decision-making. Regarding gender effect, MGA showed that gender only moderated the influence of AHA on ATTV (e.g., βWomen−βMen = .296, p < .001 [Model #6]). However, other observed gender differences (e.g. the explained variance of the model for intentions were always higher for men that for women, for instance, R2Women = .298; R2Men = .394 [Model #6]) deserve further considerations, especially for developing more effective communication strategies.

Keywords: veganism, Theory of Planned Behavior, background factors, gender moderation

Procedia PDF Downloads 340

Authors: Belgherbi Aicha, Hadjidj Ismahen, Bessaid Abdelhafid

Abstract:

The interpretation of medical images benefits from anatomical and physiological priors to optimize computer- aided diagnosis applications. Segmentation of liver and liver lesion is regarded as a major primary step in computer aided diagnosis of liver diseases. Precise liver segmentation in abdominal CT images is one of the most important steps for the computer-aided diagnosis of liver pathology. In this papers, a semi- automated method for medical image data is presented for the liver and liver lesion segmentation data using mathematical morphology. Our algorithm is currency in two parts. In the first, we seek to determine the region of interest by applying the morphological filters to extract the liver. The second step consists to detect the liver lesion. In this task; we proposed a new method developed for the semi-automatic segmentation of the liver and hepatic lesions. Our proposed method is based on the anatomical information and mathematical morphology tools used in the image processing field. At first, we try to improve the quality of the original image and image gradient by applying the spatial filter followed by the morphological filters. The second step consists to calculate the internal and external markers of the liver and hepatic lesions. Thereafter we proceed to the liver and hepatic lesions segmentation by the watershed transform controlled by markers. The validation of the developed algorithm is done using several images. Obtained results show the good performances of our proposed algorithm

Keywords: anisotropic diffusion filter, CT images, hepatic lesion segmentation, Liver segmentation, morphological filter, the watershed algorithm

Procedia PDF Downloads 443

Authors: Seyed Mehrdad Gholami

Abstract:

Nowadays, using rail transport system (Metro) is increased in most cities of The world, so the need for safe and economical way of building tunnels and subway stations is felt more and more. One of the most commonly used methods for constructing underground structures in urban areas is NATM (New Austrian tunneling method). In this method, there are some key parameters such as excavation steps and cross-sectional area that have a significant effect on the surface settlement. Settlement is a very important control factor related to safe excavation. In this paper, Finite Element Method is used by Abaqus. R6 station of Tehran Metro Line 6 is built by NATM and the construction of that is studied and analyzed. Considering the outcomes obtained from numerical modeling and comparison with the results of the instrumentation and monitoring of field, finally, the excavation step of 1 meter and longitudinal distance of 14 meters between side drifts is suggested to achieve safe tunneling with allowable settlement.

Keywords: excavation step, NATM, numerical modeling, settlement.

Procedia PDF Downloads 130

Authors: Ahmad Fahim Nasiry, Shigeo Honma

Abstract:

We examine two-dimensional oil displacement by water in a petroleum reservoir. The pore fluid is immiscible, and the porous media is homogenous and isotropic in the horizontal direction. Buckley-Leverett theory and a combination of Laplacian and Darcy’s law are used to study the fluid flow through porous media, and the Laplacian that defines the dispersion and diffusion of fluid in the sand using heavy oil is discussed. The reservoir is homogenous in the horizontal direction, as expressed by the partial differential equation. Two main factors which are observed are the water saturation and pressure distribution in the reservoir, and they are evaluated for predicting oil recovery in two dimensions by a physical and mathematical simulation model. We review the numerical simulation that solves difficult partial differential reservoir equations. Based on the numerical simulations, the saturation and pressure equations are calculated by the iterative alternating direction implicit method and the iterative alternating direction explicit method, respectively, according to the finite difference assumption. However, to understand the displacement of oil by water and the amount of water dispersion in the reservoir better, an interpolated contour line of the water distribution of the five-spot pattern, that provides an approximate solution which agrees well with the experimental results, is also presented. Finally, a computer program is developed to calculate the equation for pressure and water saturation and to draw the pressure contour line and water distribution contour line for the reservoir.

Keywords: numerical simulation, immiscible, finite difference, IADI, IDE, waterflooding

Procedia PDF Downloads 325

Authors: Chuanxiang Cheng, Tiantian Min, Jin Yue

Abstract:

Antimicrobial active packaging enables extensive biological effects to improve food safety. However, the efficacy of antimicrobial packaging hinges on factors including the diffusion rate of the active agent toward the food surface, the initial content in the antimicrobial agent, and the targeted food shelf life. Among the possibilities of antimicrobial packaging design, an interesting approach involves the incorporation of volatile antimicrobial agents into the packaging material. In this case, the necessity for direct contact between the active packaging material and the food surface is mitigated, as the antimicrobial agent exerts its action through the packaging headspace atmosphere towards the food surface. However, it still remains difficult to achieve controlled and precise release of bioactive compounds to the specific target location with required quantity in food packaging applications. Remarkably, the development of stimuli-responsive materials for electrospinning has introduced the possibility of achieving controlled release of active agents under specific conditions, thereby yielding enduring biological effects. Relative humidity (RH) for the storage of food categories such as meat and aquatic products typically exceeds 90%. Consequently, high RH can be used as an abiotic trigger for the release of active agents to prevent microbial growth. Hence, a novel RH - responsive polyvinyl alcohol/chitosan (PVA/CS) composite nanofibrous film incorporated with 4-terpineol/β-cyclodextrin inclusion complexes (4-TA@β-CD ICs) was engineered by electrospinning that can be deposited as a functional packaging materials. The characterization results showed the thermal stability of the films was enhanced after the incorporation due to the hydrogen bonds between ICs and polymers. Remarkably, the 4 wt% 4-TA@β-CD ICs/PVA/CS film exhibited enhanced crystallinity, moderate hydrophilic (Water contact angle of 81.53°), light barrier property (Transparency of 1.96%) and water resistance (Water vapor permeability of 3.17 g mm/m2 h kPa). Moreover, this film also showed optimized mechanical performance with a Young’s modulus of 11.33 MPa, a tensile strength of 19.99 MPa and an elongation at break of 4.44 %. Notably, the antioxidant and antibacterial properties of this packaging material were significantly improved. The film demonstrated the half-inhibitory concentrations (IC50) values of 87.74% and 85.11% for scavenging 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2, 2′-azinobis (3-ethylbenzothiazoline-6-sulfonic) (ABTS) free radicals, respectively, in addition to an inhibition efficiency of 65% against Shewanella putrefaciens, the characteristic bacteria in aquatic products. Most importantly, the film achieved controlled release of 4-TA under high 98% RH by inducing the plasticization of polymers caused by water molecules, swelling of polymer chains, and destruction of hydrogen bonds within the cyclodextrin inclusion complex. Consequently, low relative humidity is suitable for the preservation of nanofibrous film, while high humidity conditions typical in fresh food packaging environments effectively stimulated the release of active compounds in the film. This film with a long-term antimicrobial effect successfully extended the shelf life of Litopenaeus vannamei shrimp to 7 days at 4 °C. This attractive design could pave the way for the development of new food packaging materials.

Keywords: controlled release, electrospinning, nanofibrous film, relative humidity–responsive, shrimp preservation

Procedia PDF Downloads 61

Authors: Robert G. Nini

Abstract:

The quality of road pavement is affected mostly by the type of sub-grade which is acting as road foundation. The roads degradation is related to many factors especially the climatic conditions, the quality, and the thickness of the base materials. The thickness of this layer depends on its California Bearing Ratio (CBR) test value which by its turn is highly affected by the quantity of water infiltrated under the road after heavy rain. The capacity of the base material to drain out its water is predominant factor because any change in moisture content causes change in sub-grade strength. This paper studies the effect of the soaking period of soil especially clay on its CBR value. For this reason, we collected many clayey samples in order to study the effect of the soaking period on its CBR value. On each soil, two groups of experiments were performed: main tests consisting of Proctor and CBR test from one side and from other side identification tests consisting of other tests such as Atterberg limits tests. Each soil sample was first subjected to Proctor test in order to find its optimum moisture content which will be used to perform the CBR test. Four CBR tests were performed on each soil with different soaking period. The first CBR was done without soaking the soil sample; the second one with two days soaking, the third one with four days soaking period and the last one was done under eight days soaking. By comparing the results of CBR tests performed with different soaking time, a more detailed understanding was given to the role of the water in reducing the CBR of soil. In fact, by extending the soaking period, the CBR was found to be reduced quickly the first two days and slower after. A precise reduction factor of the CBR in relation with soaking period was found at the end of this paper.

Keywords: California Bearing Ratio, clay, proctor test, soaking period, sub-grade

Procedia PDF Downloads 127

Authors: Thomas Ogilegwu Orohu

Abstract:

This paper highlights the effect of education on farmers’ productivity in rural Nigeria which includes potential to obtain paid employment or generate income through self-help employment using skills learnt in school. The paper emphasizes that education help farmers’ in agro-processing units in production to reduce post harvest wastage. It highlights the benefits of schooling for farmers’ productivity, particularly in terms of efficiency gains and increased farm productivity. As technological innovation spread more widely within the country, the importance of formal education in farm production ought to become more apparent. Education help farmers to improve attitudes, beliefs and habits that may lead to greater willingness to accept risk, adopts innovation, save investment and generally to embrace productive practices. Finally factors affecting farmers’ education and appropriate recommendation were given with the hope that if resolutely implemented would bring the attainment of desired farm education to farmers to improve farm productivity outputs.

Keywords: benefit, education, effect, productivity

Procedia PDF Downloads 312

Authors: Wenfen Bi, Zeng Lin

Abstract:

As a developing country, China is badly in need of capital and talents to develop the socialist country with Chinese characteristics. However, a large proportion of high income people with know-how technique, wealth and management experience have immigrated or plan to immigrate to other countries. Of course, this phenomenon has attracted the attention from both the government and researchers. One explanation might be that these high-income people lack confidence in China’s social development. Based on the data on W city’s comprehensive social situation surveyed by center for the social survey research of Wuhan university (CSSR) in 2014, this paper employed the structural equation model (SEM) to evaluate whether personal income affects social confidence, via the mediating effect of the sense of social equity (sense of right equity and sense of distributive equity). Bootstrap mediation analysis revealed that after controlling Demographic variables, personal income had a significant negative influence on sense of right equity and in turn, sense of rights equity can significantly positively predict social confidence. While personal income had no significant effect on sense of distributive equity, and sense of distributive equity did not significantly affect macro social confidence. Also, the direct effects of personal income on social confidence became not significant. These findings revealed the inner mechanism of the relationship between the personal income and social confidence in contemporary China, which was caused by mediating effect of sense of rights equity. That is, the higher the personal income, the lower the sense of rights equity, the lower the social confidence. Thus, the boost of the social confidence, especially for the rich, does not only depend on the equitable distribution of material wealth, but also on the right equity and making people feel rights equally in common life.

Keywords: personal income, sense of right equity, sense of social equity, social confidence

Procedia PDF Downloads 380

Authors: Cristian Baldini

Abstract:

‘Diabesity’ is a term for diabetes occurring in the context of obesity. The positive effect of LCHF diets (low-carb, high-fat diets) is well documented: LCHF diets are at least as effective as other dietary strategies for reducing body weight, improving glycaemic control, and reducing both hyperinsulinaemia and blood glucose (reduction of HbA1c) in type 2 diabetes and have unique positive effects on blood lipid concentrations and cardiovascular risk factors. Also, in obese insulin-resistant women, food fried in extra-virgin olive oil significantly reduced both insulin and C-peptide responses after a meal. This case study shows that if combined, both dietary strategies produce a strong effect on blood glucose, resulting in a “forced” reduction of exogenous insulin injection to avoid the problem of hypoglycaemia. Blood tests after three months of this dietary treatment show how HbA1c, triglycerides, and blood lipid profile (LDL, HDL, Total Cholesterol) are improved despite the reduction of exogenous insulin injection of 80% with a parallel body weight decrease of 15%. For continuous glucose monitoring (CGM), the patient used FreeStyle Libre before and after the dietary treatment. In order to check general body functions and glycosuria, the patient used the urine test Multistix 10 SG Siemens.

Keywords: diabetes, obesity, diabesity, fat, fried foods

Procedia PDF Downloads 62

Authors: Kyungbae Pi, Kibeom Lee, Yongil Kim, Eun-Jung Lee

Abstract:

Abnormal adipocyte growth, in terms of increased cell numbers and increased cell differentiation, is considered to be a major pathological feature of obesity. Thus, the inhibition of preadipocyte mitogenesis and differentiation could help prevent and suppress obesity. The aim of this study was to assess whether extracts from Weissella koreensis 521 cells isolated from kimchi could exert anti-adipogenic effects in 3T3-L1 cells (fat cells). Differentiating 3T3-L1 cells were treated with W. koreensis 521 cell extracts (W. koreensis 521_CE), and cell viability was assessed by MTT assays. At concentrations below 0.2 mg/ml, W. koreensis 521_CE did not exert any cytotoxic effect in 3T3-L1 cells. However, treatment with W. koreensis 521_CE significantly inhibited adipocyte differentiation, as assessed by morphological analysis and Oil Red O staining of fat. W. koreensis 521_CE treatment (0.2 mg/ml) also reduced lipid accumulation by 24% in fully differentiated 3T3-L1 adipocytes. These findings collectively indicate that Weissella koreensis 521 may help prevent obesity.

Keywords: Weissella koreensis 521, 3T3-L1 cells, adipocyte differentiation, obesity

Procedia PDF Downloads 243

Authors: Zhiqiang Yan, Chen Fan, Beicheng Xia

Abstract:

Urban lakes play an invaluable role in urban water systems such as flood control, landscape, entertainment, and energy utilization, and have suffered from severe eutrophication over the past few years. To investigate the ecological response of main aquatic species and system stability to chlorine interference in shallow urban lakes, a mini system dynamic model, based on the competition and predation of main aquatic species and TP circulation, was developed. The main species of submerged macrophyte, phytoplankton, zooplankton, benthos and TP in water and sediment were simulated as variables in the model with the interference of chlorine which effect function was attenuation equation. The model was validated by the data which was investigated in the Lotus Lake in Guangzhou from October 1, 2015 to January 31, 2016. Furthermore, the eco-exergy was used to analyze the change in complexity of the shallow urban lake. The results showed the correlation coefficient between observed and simulated values of all components presented significant. Chlorine showed a significant inhibitory effect on Microcystis aeruginosa，Rachionus plicatilis, Diaphanosoma brachyurum Liévin and Mesocyclops leuckarti (Claus).The outbreak of Spiroggra spp. inhibited the growth of Vallisneria natans (Lour.) Hara, caused a gradual decrease of eco-exergy, reflecting the breakdown of ecosystem internal equilibria. It was concluded that the study gives important insight into using chlorine to achieve eutrophication control and understand mechanism process.

Keywords: system dynamic model, urban lake, chlorine, eco-exergy

Procedia PDF Downloads 202

Authors: T. Nozu, K. Hibi, T. Nishiie

Abstract:

This paper discusses the applicability of the numerical model for a damage prediction method of the accidental hydrogen explosion occurring in a hydrogen facility. The numerical model was based on an unstructured finite volume method (FVM) code “NuFD/FrontFlowRed”. For simulating unsteady turbulent combustion of leaked hydrogen gas, a combination of Large Eddy Simulation (LES) and a combustion model were used. The combustion model was based on a two scalar flamelet approach, where a G-equation model and a conserved scalar model expressed a propagation of premixed flame surface and a diffusion combustion process, respectively. For validation of this numerical model, we have simulated the previous two types of hydrogen explosion tests. One is open-space explosion test, and the source was a prismatic 5.27 m3 volume with 30% of hydrogen-air mixture. A reinforced concrete wall was set 4 m away from the front surface of the source. The source was ignited at the bottom center by a spark. The other is vented enclosure explosion test, and the chamber was 4.6 m × 4.6 m × 3.0 m with a vent opening on one side. Vent area of 5.4 m2 was used. Test was performed with ignition at the center of the wall opposite the vent. Hydrogen-air mixtures with hydrogen concentrations close to 18% vol. were used in the tests. The results from the numerical simulations are compared with the previous experimental data for the accuracy of the numerical model, and we have verified that the simulated overpressures and flame time-of-arrival data were in good agreement with the results of the previous two explosion tests.

Keywords: deflagration, large eddy simulation, turbulent combustion, vented enclosure

Procedia PDF Downloads 236

Authors: Michele Sinico

Abstract:

In the Giovanelli illusion, some collinear dots appear misaligned, when each dot lies within a circle and the circles are not collinear. In this illusion, the role of the frame of reference, determined by the circles, is considered a crucial factor. Three experiments were carried out to study the influence of directionality of the circles on the misalignment. The adjustment method was used. Participants changed the orthogonal position of each dot, from the left to the right of the sequence, until a collinear sequence of dots was achieved. The first experiment verified the illusory effect of the misalignment. In the second experiment, the influence of two different directionalities of the circles (-0.58° and +0.58°) on the misalignment was tested. The results show an over-normalization on the sequences of the dots. The third experiment tested the misalignment of the dots without any inclination of the sequence of circles (0°). Only a local illusory effect was found. These results demonstrate that the directionality of the circles, as a global factor, can increase the misalignment. The findings also indicate that directionality and the frame of reference are independent factors in explaining the Giovanelli illusion.

Keywords: Giovannelli illusion, visual illusion, directionality, misalignment, the frame of reference

Procedia PDF Downloads 175

Authors: Afzan Mahmad, Santibuana Abd Rahman, Gouri Kumar Dash, Mohd. Syafiq Bin Abdullah

Abstract:

Antibacterial activity of the methanol extract of fruit peel of Punica granatum Linn (Family: Punicaceae) was evaluated against two Gram positive and two Gram negative bacteria. The Gram positive bacteria included Staphylococcus aureus, Streptococcus pneumoniae and the Gram negative organisms included Escherichia coli and Pseudomonas aeruginosa respectively. The culture media used for antibacterial assay was Mueller Hinton agar for the growth of S. aureus, E. coli, and P. aeruginosa. The media used for the growth of S. pneumoniae was Mueller Hinton blood agar. The antibacterial assay was performed through Disc diffusion technique. The methanol extract was tested at three different concentrations (50, 100 and 200 mg/ml). Standard antibiotic discs containing vancomycin (30 μg) for S. pneumoniae, penicillin (10 units) for S. aureus, ceftriaxone (30 μg) for E. coli and ciprofloxacin (5 μg) for P. aeruginosa were used for the activity comparison. The results of the study revealed that the extract possesses antibacterial activity against S. aureus, S. pneumoniae and P. aeruginosa at all tested concentrations. The maximum zone of inhibition of 19 mm of the extract at 200 mg/ml was observed against S. pneumoniae. However, no zone of inhibition was observed against E. coli at the tested concentrations of the extract. Based on the results obtained in this study, it may be concluded that the fruit peel of P. granatum possess broad spectrum of antibacterial activity against a number bacteria.

Keywords: Punica granatum Linn., methanol extract, antibacterial, zone of inhibition

Procedia PDF Downloads 386

Authors: Zineb Abidi, Marc-Arthur Diaye

Abstract:

There exists a large empirical literature concerning the relationship between corporate social responsibility (CSR) and corporate financial performance. This literature, however, applies mainly to large corporations and/or listed firms. To the best of our knowledge, the question of whether meeting CSR requirements impacts the financial performance of small and medium-sized unlisted SMEs has not so far been analyzed. This paper aims to analyze, for the first time, the effect of CSR on the financial performance of SMEs. Using an original database including 5,257 French SMEs, we show that adopting CSR practices has a positive but weak effect on a firm’s financial performance. To develop this further, we analyzed CSR practices interactions assessing the best combination of CSR components that positively influence SME financial performance. Our results show that French SMEs benefit more from their pro-social behavior when they choose a combination of CSR components best adapted to their individual characteristics.

Keywords: corporate social responsibility, financial performance, unlisted firms, SMEs

Procedia PDF Downloads 163

Authors: Nurcan Cetinkaya, Nadide Hulya Ozdemir

Abstract:

The aim of the study was to investigate the effect of Saccharomyces cerevisiae (SC) live yeast culture on microbial protein supply to the small intestine in Kivircik male yearlings when fed with different ratio of forage and concentrate diets. Four Kivircik male yearlings with permanent rumen canula were used in the experiment. . The treatments were allocated to a 4x4 Latin square design. Diet I consisted of 70% alfalfa hay and 30% concentrate, Diet II consisted of 30% alfalfa hay and 70% concentrate, Diet I and II were supplemented with a SC. Daily urine was collected and stored at -20°C until analysis. Calorimetric methods were used for the determination of urinary allantoin and creatinin levels. The estimated microbial N supply to small intestine for Diets I, I+SC, II and II+SC were 2.51, 2.64, 2.95 and 3.43 g N/d respectively. Supplementation of Diets I and II with SC significantly affected the allantoin levels in µmol/W0. 75 (p<0.05). Mean creatinine values in µmol/W0. 75 and allantoin:creatinin ratios were not significantly different among diets. In conclusion, supplementation with SC live yeast culture had a significant effect on urinary allantoin excretion and microbial protein supply to small intestine in Kivircik yearlings fed with high concentrate Diet II (P<0.05). Hence urinary allantoin excretion may be used as a tool for estimating microbial protein supply in Kivircık yearlings. However, further studies are necessary to understand the metabolism of Saccharomyces cerevisiae live yeast culture with different forage: concentrate ratio in Kıvırcık Yearlings.

Keywords: allantoin, creatinin, Kivircik yearling, microbial nitrogen, Saccharomyces cerevisia

Procedia PDF Downloads 406

Authors: Anis Eloud, Sayed Chehaibi

Abstract:

Compaction of agricultural soils as a result of the passage of heavy machinery on the fields is a problem that affects many agronomists and farmers since it results in a loss of yield of most crops. To remedy this, and raise the overall future of the food security challenge, we must study and understand the process of soil degradation. The present review is devoted to understanding the effect of repeated passages on agricultural land. The experiments were performed on a plot of the area of the ESIER, characterized by a clay texture in order to quantify the soil compaction caused by the wheels of the tractor during repeated passages on agricultural land. The test tractor CASE type puissance 110 hp and 5470 kg total mass of 3500 kg including the two rear axles and 1970 kg on the front axle. The state of soil compaction has been characterized by measuring its resistance to penetration by means of a penetrometer and direct manual reading, the density and permeability of the soil. Soil moisture was taken jointly. The measurements are made in the initial state before passing the tractor and after each pass varies from 1 to 7 on the track wheel inflated to 1.5 bar for the rear wheel and broke water to the level of valve and 4 bar for the front wheels. The passages are spaced to the average of one week. The results show that the passage of wheels on a farm tilled soil leads to compaction and the latter increases with the number of passages, especially for the upper 15 cm depth horizons. The first passage is characterized by the greatest effect. However, the effect of other passages do not follow a definite law for the complex behavior of granular media and the history of labor and the constraints it suffers from its formation.

Keywords: wheel traffic, tractor, soil compaction, wheel

Procedia PDF Downloads 475

Authors: Anil Giri, Kyle Lovercamp, Sankalp Sharma

Abstract:

Farm level incomes fluctuate significantly due to extreme weather events such as drought. In the light of recent extreme weather events it is important to understand the implications of extreme weather events, flood and drought, on farm level incomes. This study examines the variation in farm level incomes for the United States in drought and no- drought years. Factoring heterogeneity in different enterprises (crop, livestock) and geography this paper analyzes the impact of drought in farm level incomes at state and national level. Livestock industry seems to be affected more by the lag in production of input feed for production, crops, as preliminary results show. Furthermore, preliminary results also show that while crop producers are not affected much due to drought, as price and quantity effect worked on opposite direction with same magnitude, that was not the case for livestock and horticulture enterprises. Results also showed that even when price effect was not as high the crop insurance component helped absorb much of shock for crop producers. Finally, the effect was heterogeneous for different states more on the coastal states compared Midwest region. This study should generate a lot of interest from policy makers across the world as some countries are actively seeking to increase subsidies in their agriculture sector. This study shows how subsidies absorb the shocks for one enterprise more than others. Finally, this paper should also be able to give an insight to economists to design/recommend policies such that it is optimal given the production level of different enterprises in different countries.

Keywords: farm level income, United States, crop, livestock

Procedia PDF Downloads 274

Authors: Muzamil Mahmood, Afshan Naseem, Muhammad Zeeshan Mirza, Yasir Ahmad, Masood Raza

Abstract:

The purpose of this research is to analyze how aviation maintenance workers’ characteristics and work demand affect their development of work-related musculoskeletal disorders (WMSDs). Guided by literature on task characteristics, work demand, and WMSDs, data is collected from 128 aviation maintenance workers of private and public airlines. Data is then analyzed through descriptive and inferential statistics. It is found that task characteristics have a significant positive effect on WMSDs and an increase in tasks performed by aviation maintenance workers leads to increase in WMSDs. Work demand did not have a significant effect on WMSDs. The task characteristics of aviation maintenance workers moderates the relationship between their work demand and WMSDs. This reveals that task characteristics of aviation maintenance workers enhance the effect of work demand on WMSDs. The task characteristics of aviation maintenance workers are challenging and unpredictable. Subsequently, WMSDs are prevalent among aviation maintenance workers. The work demand of aviation maintenance workers does not influence their development of WMSDs. Pakistan Civil Aviation Authority should minimize the intensity of tasks assigned to aviation maintenance workers by introducing work dynamisms such as task sharing, job rotation, and probably teleworking to enhance flexibility. Human Resource and Recruitment Department need to consider the ability and fitness levels of potential aviation maintenance workers during recruitment. In addition, regular physical activities and ergonomic policies should be put in place by the management of the Pakistan Civil Aviation Authority to reduce the incidences of WMSDs.

Keywords: work related musculoskeletal disorders, ergonomics, occupational health and safety, human factors

Procedia PDF Downloads 151

Authors: Harish K. Arya, Kulwant Singh, R. K. Saxena

Abstract:

The heat flow in weldment changes its nature from 2D to 3D with the increase in plate thickness. For welding of thicker plates the heat loss in thickness direction increases the cooling rate of plate. Since the cooling rate changes, the various bead parameters like bead penetration, bead height and bead width also got affected by it. The present study incorporates the effect of variable plate thickness on penetration and bead width. The penetration reduces with increase in plate thickness due to heat loss in thickness direction for same heat input, while bead width increases for thicker plate due to faster cooling.

Keywords: submerged arc welding, plate thickness, bead geometry, cooling rate

Procedia PDF Downloads 326

Authors: See-Yuan Cheng, Kwang-Yhee Chin, Shuhaimi Mansor

Abstract:

Rear-roof spoiler is commonly used for improving the aerodynamic performance of road vehicles. This study aims to investigate the effect of yaw angle on the effectiveness of strip-type rear-roof spoiler in providing lower drag and lift coefficients of a hatchback model. A computational fluid dynamics (CFD) method was used. The numerically obtained results were compared to the experimental data for validation of the CFD method. At increasing yaw angle, both the drag and lift coefficients of the model were to increase. In addition, the effectiveness of spoiler was deteriorated. These unfavorable effects were due to the formation of longitudinal vortices around the side edges of the model that had caused the surface pressure of the model to drop. Furthermore, there were significant crossflow structures developed behind the model at larger yaw angle, which were associated with the drop in the surface pressure of the rear section of the model and cause the drag coefficient to rise.

Keywords: Ahmed model, aerodynamics, spoiler, yaw angle

Procedia PDF Downloads 354

Authors: K. C. Ching

Abstract:

There is growing public concern over the increasing prevalence of student suicide in Hong Kong. Some identify the problem with insufficient social support, while some attribute it to the vast fluctuations in emotional experience and the hindrances to emotion-regulation, both typical of adolescence and emerging adulthood. This study is thus designed to explore the respective effect of perceived social support and emotion self-confidence, on positive emotions and negative emotions. Fifty-seven Hong Kong higher-education students (17 males, 40 females) aged between 18 and 25 (M = 21.78) responded to an online questionnaire consisted of self-reported measures of perceived social support, emotional self-confidence, positive emotions, and negative emotions. Hierarchical regression analysis revealed that emotional self-confidence positively associated with positive emotions and negatively with negative emotions, while perceived social support positively associated with positive emotions but was not related to negative emotions. Perceived social support and emotional self-confidence both predicted positive emotions, but did not interact to predict any emotional outcome. It is concluded that students’ positive and negative emotional experiences are closely related to their emotion-regulation process. But for social support, its effect is merely protective, meaning that although perceived social support generally promotes positive emotions, it alone does not suffice to alleviate students’ negative emotions. These conclusions carry profound implications to suicide prevention practices, including that most existing suicide prevention campaigns should advance from merely fostering mutual support to directly promoting adaptive coping of emotional negativity.

Keywords: emerging adulthood, emotional self-confidence, hong kong, perceived social support, suicide prevention

Procedia PDF Downloads 132

Authors: Pooyan Changizian, Zhongwen Yao

Abstract:

The purpose of current study is to make an excellent correlation between mechanical properties and microstructures of ion irradiated X-750 Ni-based superalloy. Towards this end, two different irradiation procedures were carried out, including single Ni ion irradiation and pre-helium implantation with subsequent Ni ion irradiation. Nano-indentation technique was employed to evaluate the mechanical properties of irradiated material. The nano-hardness measurements depict highly different results for two irradiation procedures. Single ion irradiated X-750 shows softening behavior; however, pre-helium implanted specimens present significant hardening compared to the un-irradiated material. Cross-section TEM examination demonstrates that softening is attributed to the γ׳-precipitate instability (disordering/dissolution) which overcomes the hardening effect of irradiation-induced defects. In contrast, the presence of cavities or helium bubbles is probably the main cause for irradiation-induced hardening of helium implanted samples.

Keywords: Inconel X-750, nanoindentation, helium bubbles, defects

Procedia PDF Downloads 213

Authors: G. Balogh, I. A. Szabó, P.Z. Kovács

Abstract:

Mechanical stress has a strong effect on the magnitude of the Barkhausen-noise in structural steels. Because the measurements are performed at the surface of the material, for a sample sheet, the full effect can be described by a biaxial stress field. The measured Barkhausen-noise is dependent on the orientation of the exciting magnetic field relative to the axis of the stress tensor. The sample inhomogenities including the residual stress also modifies the angular dependence of the measured Barkhausen-noise. We have developed a laboratory device with a cross like specimen for bi-axial bending. The measuring head allowed performing excitations in two orthogonal directions. We could excite the two directions independently or simultaneously with different amplitudes. The simultaneous excitation of the two coils could be performed in phase or with a 90 degree phase shift. In principle this allows to measure the Barkhausen-noise at an arbitrary direction without moving the head, or to measure the Barkhausen-noise induced by a rotating magnetic field if a linear superposition of the two fields can be assumed.

Keywords: Barkhausen-noise, bi-axial stress, stress measuring, stress dependency

Procedia PDF Downloads 290

Authors: Emmanuel Ogundimu, Esther Akinlabi, Mutiu Erinosho

Abstract:

The aim of this paper is to study the effect of welding current on the microstructure and the mechanical properties. Material characterizations were conducted on a 6 mm thick plates of type-304 austenite stainless steel, welded by TIG welding process at two different welding currents of 150 A (Sample F3) and 170 A (Sample F4). The tensile strength and the elongation obtained from sample F4 weld were approximately 584 MPa and 19.3 %; which were higher than sample F3 weld. The average microhardness value of sample F4 weld was found to be 235.7 HV, while that of sample F3 weld was 233.4 HV respectively. Homogenous distribution of iron (Fe), chromium (Cr) and nickel (Ni) were observed at the welded joint of the two samples. The energy dispersive spectroscopy (EDS) analysis revealed that Fe, Cr, and Ni made up the composition formed in the weld zone. The optimum welding current of 170 A for TIG welding of type-304 austenite stainless steel can be recommended for high-tech industrial applications.

Keywords: microhardness, microstructure, tensile, MIG welding, process, tensile, shear stress TIG welding, TIG-MIG welding

Procedia PDF Downloads 188

Authors: R. Gounina-Allouane, N. Ouali, F. Z. Berrabah, A. Bentaleb

Abstract:

For a long time, the Gram-positive spore-forming bacteria Bacillus thuringiensis (Bt) has been widely used in biological control against devastating and disease vectors insects. This is due to the insecticidal activity of its crystalline parasporal inclusion (crystals) predominantly comprised of one or more proteins (Cry and Cyt proteins) also called δ-endotoxins, produced during sporulation. The shape and composition of Bt crystals vary among strains and crystalline proteins are extremely varied (more than 475 cry gene were discovered). The insecticidal activity of Bt crystals is very well studied, thus their insecticidal mode of action is well established, however, their antimicrobial effect is largely unknown. The lack of data on the antimicrobial effect of crystalline proteins of Bt and the need for searching new antimicrobial molecules encouraged us to carried out this study. The antibacterial effect of δ-endotoxines produced by two Bt stains; a strain isolated from soil at northern of Algeria (Bt 7.2.B), and a strain isolated from a bioinsecticide (Bacillus thuringiensis var aizawai), activated by proteolysis, was assayed on clinical bacterial strains and ATCC collection ones respectively. Gram positive and negative clinical bacterial strains (Escherichia coli, Klebsiella pneumonaie, Pseudomonas aeruginosa, Staphylococcus aureus) were sensitive to activated Bt 72B endotoxins. Similarly, bacterial strains from ATCC collection (Escherichia coli ATCC 25922, Pseudomonas aerugenosa ATCC 27853, Staphylococcus aureus ATCC 25923) were sensitive to activated B. thuringiensis var aizawai δ-endotoxines. The activated δ-endotoxins were separated by SDS-PAGE.

Keywords: Bacillus thuringiensis, crystals, cry proteins, δ-endotoxins, antibacterial activity

Procedia PDF Downloads 444

Authors: Harish Kumar Arya, Kulwant Singh, R. K Saxena, Deepti Jaiswal

Abstract:

The heat flow in weldment changes its nature from 2D to 3D with the increase in plate thickness. For welding of thicker plates the heat loss in thickness direction increases the cooling rate of plate. Since the cooling rate changes, the various bead parameters like bead penetration, bead height and bead width also got affected by it. The present study incorporates the effect of variable plate thickness on bead geometry and dilution. The penetration reduces with increase in plate thickness due to heat loss in thickness direction, while bead width and reinforcement increases for thicker plate due to faster cooling.

Keywords: submerged arc welding, plate thickness, bead geometry, cooling rate

Procedia PDF Downloads 281

Authors: Tej Varma Y, Debi D. Pant

Abstract:

Photophysics and rotational dynamics of the fluorescent probe, 6-methoxyquinoline (6MQ) with cationic surfactant, alkyltrimethylammonium bromide (nTAB) micelle solutions have been investigated (n = 12, 14 and 16). Absorption and emission peaks of the dye have been observed to shift at concentrations around critical micellar concentration (cmc) of nTAB compared to that of bulk solutions suggesting probe is in a lower polar environment. The probe senses changes in polarity (ET (30)) brought about by variation of surfactant chain length concentration and is invariably solubilized in the aqueous interface or palisade layer. The order of change in polarity observed was DTAB > CTAB > TTAB. The binding constant study shows that the probe binds strongest with TTAB (is of the order TTAB > CTAB > DTAB) due to deeper penetration into the micelle. The anisotropy decay for the probe in all the nTAB micelles studied have been rationalized based on a two-step model consisting of fast-restricted rotation of the probe and slow lateral diffusion of the probe in the micelle that is coupled to the overall rotation of the micelle. Fluorescence lifetime measurements of probe in the cationic micelles demonstrate the close proximity of the 6MQ to the Br - counterions. The fluorescence lifetimes of TTAB and DTAB are much shorter than in CTAB. These results indicate that 6MQ resides to a substantial degree in the head group region of the micelles. All the changes observed in the steady state fluorescence, microenvironment, fluorescence lifetimes, fluorescence anisotropy, and other calculations are in agreement with each other suggesting binding of the cationic surfactant with the neutral dye molecule.

Keywords: photophysics, chain length, ntaB, micelles

Procedia PDF Downloads 627