Search results for: negative transfer
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 7394

Search results for: negative transfer

5744 Exploring the Impact of Domestic Credit Extension, Government Claims, Inflation, Exchange Rates, and Interest Rates on Manufacturing Output: A Financial Analysis.

Authors: Ojo Johnson Adelakun

Abstract:

This study explores the long-term relationships between manufacturing output (MO) and several economic determinants, interest rate (IR), inflation rate (INF), exchange rate (EX), credit to the private sector (CPSM), gross claims on the government sector (GCGS), using monthly data from March 1966 to December 2023. Employing advanced econometric techniques including Fully Modified Ordinary Least Squares (FMOLS), Dynamic Ordinary Least Squares (DOLS), and Canonical Cointegrating Regression (CCR), the analysis provides several key insights. The findings reveal a positive association between interest rates and manufacturing output, which diverges from traditional economic theory that predicts a negative correlation due to increased borrowing costs. This outcome is attributed to the financial resilience of large enterprises, allowing them to sustain investment in production despite higher interest rates. In addition, inflation demonstrates a positive relationship with manufacturing output, suggesting that stable inflation within target ranges creates a favourable environment for investment in productivity-enhancing technologies. Conversely, the exchange rate shows a negative relationship with manufacturing output, reflecting the adverse effects of currency depreciation on the cost of imported raw materials. The negative impact of CPSM underscores the importance of directing credit efficiently towards productive sectors rather than speculative ventures. Moreover, increased government borrowing appears to crowd out private sector credit, negatively affecting manufacturing output. Overall, the study highlights the need for a coordinated policy approach integrating monetary, fiscal, and financial sector strategies. Policymakers should account for the differential impacts of interest rates, inflation, exchange rates, and credit allocation on various sectors. Ensuring stable inflation, efficient credit distribution, and mitigating exchange rate volatility are critical for supporting manufacturing output and promoting sustainable economic growth. This research provides valuable insights into the economic dynamics influencing manufacturing output and offers policy recommendations tailored to South Africa’s economic context.

Keywords: domestic credit, government claims, financial variables, manufacturing output, financial analysis

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5743 Numerical Modeling of Turbulent Natural Convection in a Square Cavity

Authors: Mohammadreza Sedighi, Mohammad Said Saidi, Hesamoddin Salarian

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A numerical study has been performed to investigate the effect of using different turbulent models on natural convection flow field and temperature distributions in partially heated square cavity compare to benchmark. The temperature of the right vertical wall is lower than that of heater while other walls are insulated. The commercial CFD codes are used to model. Standard k-w model provided good agreement with the experimental data.

Keywords: Buoyancy, Cavity, CFD, Heat Transfer, Natural Convection, Turbulence

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5742 The Revitalization of South-south Cooperation: Evaluation of South African Direct Investment in Cameroon

Authors: Albert Herve Nkolo Mpoko

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The Foreign Direct Investment (FDI) landscape in Cameroon has garnered significant attention from both European and Asian nations due to perceived benefits such as capital infusion, technology transfer, and potential for economic expansion. However, it is noteworthy that South Africa's investment presence remains comparatively subdued in Cameroon, lagging behind that of Europe and Asia. Equally surprising is the limited footprint of Africa's economic powerhouse within other African economies. This study delved into four specific facets of South African investment in Cameroon. Initially, it focused on identifying South African companies operating within Cameroon. Subsequently, the analysis encompassed assessing the correlation between South African investment and poverty alleviation. Additionally, the study examined the nexus between South African investment and technological advancement, and underscored the significance of investment incentives in both countries Key findings of the research shed light on several crucial points. South Africa ought to reassess its economic engagement with Francophone Africa, particularly Cameroon. Despite existing policies aimed at fostering investment, there remains substantial ground to cover in this realm. The proliferation of South African enterprises in Cameroon holds the potential to ameliorate poverty and foster employment opportunities across both nations. The advent of South African firms in Cameroon can catalyse technological advancements within the region. Data collection involved surveying 100 executives from the respective administrations and conducting ten interviews. The gathered data underwent triangulation, wherein quantitative findings were juxtaposed with qualitative insights. In conclusion, the study underscores the underutilization of Cameroon by South Africa, emphasizing the untapped potential for mutual economic growth. Furthermore, it posits that the success of South Africa's multinational corporations abroad could serve as a pivotal pillar for sustaining its domestic economy.

Keywords: FDI, transfer of technology, South-South cooperation, mutual economic growth

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5741 Sub-Optimum Safety Performance of a Construction Project: A Multilevel Exploration

Authors: Tas Yong Koh, Steve Rowlinson, Yuzhong Shen

Abstract:

In construction safety management, safety climate has long been linked to workers' safety behaviors and performance. For this reason, safety climate concept and tools have been used as heuristics to diagnose a range of safety-related issues by some progressive contractors in Hong Kong and elsewhere. However, as a diagnostic tool, safety climate tends to treat the different components of the climate construct in a linear fashion. Safety management in construction projects, in reality, is a multi-faceted and multilevel phenomenon that resembles a complex system. Hence, understanding safety management in construction projects requires not only the understanding of safety climate but also the organizational-systemic nature of the phenomenon. Our involvement, diagnoses, and interpretations of a range of safety climate-related issues which culminated in the project’s sub-optimum safety performance in an infrastructure construction project have brought about such revelation. In this study, a range of data types had been collected from various hierarchies of the project site organization. These include the frontline workers and supervisors from the main and sub-contractors, and the client supervisory personnel. Data collection was performed through the administration of safety climate questionnaire, interviews, observation, and document study. The findings collectively indicate that what had emerged in parallel of the seemingly linear climate-based exploration is the exposition of the organization-systemic nature of the phenomenon. The results indicate the negative impacts of climate perceptions mismatch, insufficient work planning, and risk management, mixed safety leadership, workforce negative attributes, lapsed safety enforcement and resources shortages collectively give rise to the project sub-optimum safety performance. From the dynamic causation and multilevel perspective, the analyses show that the individual, group, and organizational levels issues are interrelated and these interrelationships are linked to negative safety climate. Hence the adoption of both perspectives has enabled a fuller understanding of the phenomenon of safety management that point to the need for an organizational-systemic intervention strategy. The core message points to the fact that intervention at an individual level will only meet with limited success if the risks embedded in the higher levels in group and project organization are not addressed. The findings can be used to guide the effective development of safety infrastructure by linking different levels of systems in a construction project organization.

Keywords: construction safety management, dynamic causation, multilevel analysis, safety climate

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5740 Dry Needling Treatment in 38 Cases of Chronic Sleep Disturbance

Authors: P. Gao, Z. Q. Li, Y. G. Jin

Abstract:

In the past 10 years, computers and cellphones have become one of the most important factors in our lives, and one which has a tremendously negative impact on our muscles. Muscle tension may be one of the causes of sleep disturbance. Tension in the shoulders and neck can affect blood circulation to the muscles. This research uses a dry needling treatment to reduce muscle tension in order to determine if the strain in the head and shoulders can influence sleep duration. All 38 patients taking part in the testing suffered from tinnitus and have been experiencing disturbed sleep for at least one to five years. Even after undergoing drug therapy treatments and traditional acupuncture therapies, their sleep disturbances have not shown any improvement. After five to 10 dry needling treatments, 24 of the patients reported an improvement in their sleep duration. Five patients considered themselves to be completely recovered, while 12 patients experienced no improvement. This study investigated these pathogenic and therapeutic problems. The standard treatment for sleep disturbances is drug-based therapy; the results of most standard treatments are unfortunately negative. The result of this clinical research has demonstrated that: The possible cause of sleep disturbance for a lot of patients is the result of tensions in the neck and shoulder muscles. Blood circulation to those muscles is also influenced by the duration of sleep. Hypertonic neck and shoulder muscles are considered to impact sleeping patterns and lead to disturbed sleep. Poor posture, often adopted while speaking on the phone, is one of the main causes of hypertonic neck and shoulder muscle problems. The dry needling treatment specifically focuses on the release of muscle tension.

Keywords: dry needling, muscle tension, sleep duration, hypertonic muscles

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5739 Psychological Characteristic Patients with Takotsubo - Etiology of Stress and Family Functioning

Authors: Treder Natalia, Siemiński Mariusz

Abstract:

Takotsubo cardiomyopathy (TC) is a recently defined clinical entity. First described by Japanese researchers, today is diagnosed worldwide in 1-2% of patients admitted with the preliminary diagnosis of Acute Coronary Syndrome. The etiology of takotsubo cardiomyopathy remains still largely unknown. Currently, the most likely cause of takotsubo is direct cytotoxicity caused by catecholamine surge triggered by emotional stress. There is a strong relation between recent severe emotional stress and TC. The aim of this study was to analysis the role of stress and personality as a risk factor of TT. The presented research involves 35 people who are diagnosed TC. All patients were women, mean age 60 years. The methods used in the research are popular psychological tests: Perceived Stress Scale, DS14 scale to measure type D personality, The Neo-Five Factor Inventory of Personality and psychological interview. The obtained results prove that stress events may directly precede or even release TC. The stressful events occurred directly before the symptoms in 75% examined. 65% assessed their family life as very stressful. Examiners have also a high level of experienced stress. Only 25% of the TC were classified as having type D personality but they have a high level of negative affectivity. The subjects had a high level of extraversion, openness to experiences and an average level of neuroticism. The results suggested that such a type of personality profile may predispose to the development of takotsubo cardiomyopathy. Patients with TT are the individuals who reveal joint tendency to the experience of negative emotions and very stressful family life.

Keywords: stress, personality trails, familiar problems, Takotsubo cardiomyopathy

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5738 Comparative Study of Urban Structure between an Island-Type and a General-Type City

Authors: Tomoya Oshiro, Hiroko Ono

Abstract:

Japan's aging population is increasing due to the decrease in birthrate. It causes various problems like the decrease in the gross domestic product of the country. The reason is why the local government of Japan has been on the way to a sustainable city recently. Then it is essential to get control of an urban structure to make the compact city successful. There are many kinds of paper about the compact city; however, the paper about a compact city of the island-type city is less. The purpose of this study is to clarify difference of urban structure between an island-type and a general city type. The method which has conducted in this research has two steps. First of all, by using evaluation indexes in the handbook, we evaluated the urban structures among each same -population-class cities from 50,000 to 100,000 people. Next, to clear the difference about the urban structure and feature between island-type and general-type cities compare the radar chart which is composed with each evaluation indexes of urban structure. Moreover, in order to clarify the relationship between evaluation indexes and the place of residence by using GIS software to show up population density on the map. As a result of this research, the management of local government and the local economy in evaluation indexes are indicated to be negative point in comparison of island-type cities with general cities. However, evaluation indexes of safety/security and low-carbon/energy are proved to be positive point. The research to find the difference features of the island-type of urban structure proves that the management of local government or the local economy is negative point in these island-type cities. In addition, the public transportation coverage in Miyako Island, Sado Island, and Amakusa Island show low value compare with other islands and average value. Relationship between evaluation indexes of an urban structure and the place of residence prove that the place of residence is related to public transportation coverage. If the place of residence is spread out, the public transportation coverage will be decreased. The results of this research reveal that the finances in island-type cities are negative point compare to general cities. This problem is caused by declining population. In addition, the place of residence is related to the public transportation coverage. Even though, it needs a much money to increase the public transportation coverage. It is possibly to cause other problems furthermore the aspect of finance is influenced by that as well. The conclusion in this research suggests that it is important for creating the compact city in island-type cities that we first need to address solving the problems about the management of local government and the local economy.

Keywords: sustainable city, comparative analysis, geographic information system, urban structure

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5737 Seam Slippage of Light Woven Fabrics with Regards to Sewing Parameters

Authors: Mona Shawky, Khaled M. Elsheikh, Heba M. Darwish, Eman Abd El Elsamea

Abstract:

Seams are the basic component in the structure of any apparel. The seam quality of the garment is a term that indicates both the aesthetic and functional performance of the garment. Seam slippage is one of the important properties that determine garment performance. Lightweight fabrics are preferred for their aesthetic properties. Since seam slippage is one of the most occurable faults for woven garments, in this study, a design of experiment of the following sewing parameters (three levels of needle size, three levels of stitch density, three levels of the seam allowance, two levels of sewing thread count, and two fabric types) was used to obtain the effect of the interaction between different sewing parameters on-seam slippage force. Two lightweight polyester woven fabrics with different constructions were used with lock stitch 301 to perform this study. Regression equations which can predict seam slippage force in both warp and weft directions were concluded. It was found that fabric type has a significant positive effect on seam slippage force in the warp direction, while it has a significant negative effect on seam slippage force on weft direction. Also, the interaction between needle size and stitch density has a significant positive effect on seam slippage force on warp direction, while the interaction between stitch density and seam allowance has a negative effect on seam slippage force in the weft direction.

Keywords: needle size, regression equation, seam allowance, seam slippage, stitch density

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5736 Academic Achievement Differences in Grandiose and Vulnerable Narcissists and the Mediating Effects of Self-Esteem and Self-Efficacy

Authors: Amber Dummett, Efstathia Tzemou

Abstract:

Narcissism is a personality trait characterized by selfishness, entitlement, and superiority. Narcissism is split into two subtypes, grandiose narcissism (GN) and vulnerable narcissism (VN). Grandiose narcissists are extraverted and arrogant, while vulnerable narcissists are introverted and insecure. This study investigates the psychological mechanisms that lead to differences in academic achievement (AA) between grandiose and vulnerable narcissists, specifically the mediating effects of self-esteem and self-efficacy. While narcissism is considered to be a negative trait, one of the Dark Triads, GN, has been found to have some benefits; therefore, this study considers if better AA is one of them. Moreover, further research into VN is essential to fully compare and contrast it with GN. We hypothesize that grandiose narcissists achieve higher marks due to having high self-esteem and self-efficacy. In comparison, we hypothesize that vulnerable narcissists underperform and achieve lower marks due to having low self-esteem and self-efficacy. Two online surveys were distributed to undergraduate university students. The first was a collection of scales measuring the mentioned dimensions and semester one AA, and the second investigated end of year AA. Sequential mediation analyses were conducted using the gathered data. Our analysis shows that neither self-esteem nor self-efficacy mediates the relationship between GN and AA. GN positively predicts self-esteem but has no relationship with self-efficacy. Self-esteem does not mediate the relationship between VN and AA. VN has a negative indirect effect on AA via self-efficacy, and VN negatively predicts self-esteem. Self-efficacy positively predicts AA. GN does not affect AA through the mediation of self-esteem and then self-efficacy, and neither does VN in this way. Overall, having grandiose or vulnerable narcissistic traits does not affect students’ AA. However, being highly efficacious does lead to academic success; therefore, universities should employ methods to improve the self-efficacy of their students.

Keywords: academic achievement, grandiose narcissism, self-efficacy, self-esteem, vulnerable narcissism

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5735 Attitudes towards People with Disability and Career Interest in Disability Studies: A Study of Clinical Medical Students of a Tertiary Institution in Southeastern Nigeria

Authors: Ebele V. Okoli, Emmanuel Nwobi, Dozie Ezechukwu, Ijeoma Itanyi

Abstract:

One in seven people worldwide suffer from a disability. 80% of people with disabilities live in developing countries. Negative attitudes and misconceptions among health-care providers constitute barri¬ers to optimal health care for people with disabilities. This underscores the relevance of a study of the attitude of Nigerian medical students towards disability and their willingness to work in the disability sector. This was a descriptive cross-sectional study conducted among 254 penultimate and final year medical students of a university in southeastern Nigeria. The mean age of the students was 24.8 ± 3.12 years. Majority of the students were male (75.2%), single (96.9%), of the Igbo tribe (86.6%), Christian (97.6%) and grew up in urban areas (68.1%). Results indicated that the medical students had a predominantly positive attitude towards people with disability as 73.8% had a positive attitude and mean attitude score was 67.03 ± 0.14 (positive attitude = 61 – 120, negative attitude = 0 - 60). Chi-square analysis did not show any significant effect of demographic and social factors on the students’ attitude towards People with Disabilities. The students were mostly willing to work in areas that address the challenges of people with disability (70.4%) but a greater proportion had never heard about Disability Studies (67.5%). About a third of the students (33.2%) would like to travel abroad to practice in the disability sector. Conclusions: The students generally had a positive attitude towards people with disability and a greater percentage were willing to work in the disability sector in their future career. About two-thirds had however, never heard about disability studies. There was some potential for brain drain among the students as a third of the population intended to practice abroad on graduation.

Keywords: attitudes, career interest, disability, medical students

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5734 Design of an Improved Distributed Framework for Intrusion Detection System Based on Artificial Immune System and Neural Network

Authors: Yulin Rao, Zhixuan Li, Burra Venkata Durga Kumar

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Intrusion detection refers to monitoring the actions of internal and external intruders on the system and detecting the behaviours that violate security policies in real-time. In intrusion detection, there has been much discussion about the application of neural network technology and artificial immune system (AIS). However, many solutions use static methods (signature-based and stateful protocol analysis) or centralized intrusion detection systems (CIDS), which are unsuitable for real-time intrusion detection systems that need to process large amounts of data and detect unknown intrusions. This article proposes a framework for a distributed intrusion detection system (DIDS) with multi-agents based on the concept of AIS and neural network technology to detect anomalies and intrusions. In this framework, multiple agents are assigned to each host and work together, improving the system's detection efficiency and robustness. The trainer agent in the central server of the framework uses the artificial neural network (ANN) rather than the negative selection algorithm of AIS to generate mature detectors. Mature detectors can distinguish between self-files and non-self-files after learning. Our analyzer agents use genetic algorithms to generate memory cell detectors. This kind of detector will effectively reduce false positive and false negative errors and act quickly on known intrusions.

Keywords: artificial immune system, distributed artificial intelligence, multi-agent, intrusion detection system, neural network

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5733 Implementation of Project-Based Learning with Peer Assessment in Large Classes under Consideration of Faculty’s Scare Resources

Authors: Margit Kastner

Abstract:

To overcome the negative consequences associated with large class sizes and to support students in developing the necessary competences (e.g., critical thinking, problem-solving, or team-work skills) a marketing course has been redesigned by implementing project-based learning with peer assessment (PBL&PA). This means that students can voluntarily take advantage of this supplementary offer and explore -in addition to attending the lecture where clicker questions are asked- a real-world problem, find a solution, and assess the results of peers while working in small collaborative groups. In order to handle this with little further effort, the process is technically supported by the university’s e-learning system in such a way that students upload their solution in form of an assignment which is then automatically distributed to peer groups who have to assess the work of three other groups. Finally, students’ work is graded automatically considering both, students’ contribution to the project and the conformity of the peer assessment. The purpose of this study is to evaluate students’ perception of PBL&PA using an online-questionnaire to collect the data. More specifically, it aims to discover students’ motivations for (not) working on a project and the benefits and problems students encounter. In addition to the survey, students’ performance was analyzed by comparing the final grades of those who participated in PBL&PA with those who did not participate. Among the 260 students who filled out the questionnaire, 47% participated in PBL&PA. Besides extrinsic motivations (bonus credits), students’ participation was often motivated by learning and social benefits. Reasons for not working on a project were connected to students’ organization and management of their studies (e.g., time constraints, no/wrong information) and teamwork concerns (e.g., missing engagement of peers, prior negative experiences). In addition, high workload and insufficient extrinsic motivation (bonus credits) were mentioned. With regards to benefits and problems students encountered during the project, students provided more positive than negative comments. Positive aspects most often stated were learning and social benefits while negative ones were mainly attached to the technical implementation. Interestingly, bonus credits were hardly named as a positive aspect meaning that intrinsic motivations have become more important when working on the project. Team aspects generated mixed feelings. In addition, students who voluntarily participated in PBL&PA were, in general, more active and utilized further course offers such as clicker questions. Examining students’ performance at the final exam revealed that students without participating in any of the offered active learning tasks performed poorest in the exam while students who used all activities were best. In conclusion, the goals of the implementation were met in terms of students’ perceived benefits and the positive impact on students’ exam performance. Since the comparison of the automatic grading with faculty grading showed valid results, it is possible to rely only on automatic grading in the future. That way, the additional workload for faculty will be within limits. Thus, the implementation of project-based learning with peer assessment can be recommended for large classes.

Keywords: automated grading, large classes, peer assessment, project-based learning

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5732 Asymmetric Linkages Between Global Sustainable Index (Green Bond) and Cryptocurrency Markets with Portfolio Implications

Authors: Faheem Ur Rehman, Muhammad Khalil Khan, Miao Qing

Abstract:

This study investigated the asymmetric links and portfolio strategies between green bonds and the markets of three different cryptocurrencies, i.e., green, Islamic, and conventional, using data from January 1, 2018, to April 8, 2022, and employing asymmetric TVP-VAR model to quantify risk spillovers in the network analysis. In addition, we use the minimum variance, minimum correlation, and minimum connectedness methodologies to assess the portfolio implications. The results of the asymmetric dynamic connectedness index (TCI) model show that by adopting cryptocurrencies for digital finance, risk spillovers are found to be reduced. The findings of net directional connectedness demonstrate that during the study period, green bonds consistently get return spillovers from all other network variables. Positive return spillovers are bigger in magnitude than negative ones. These results imply that the influence of the green bond market on the cryptocurrency markets is decreasing. Positive return spillovers generate higher connectedness values for (HG, BNB, and TRX) coins and persistent net recipients in the specific network. On the other hand, Cardano and ADA coins are persistent net transmitters in the system. XLM and MIOTA's responsibilities shift over time, and there is evidence of asymmetry when both positive and negative returns are considered. According to the pairwise portfolio weights, BNB vs. BTC has the largest portfolio weights in the system, followed by BNB vs. Ethereum, suggesting the best investment strategies in the network.

Keywords: asymmetric TVP-VAR, global sustainable index, cryptocurrency, portfolios

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5731 Association between Copper Uptake and Decrease of Copper (hypocupremia) in Burn Patients-Infected Pseudomonas aeruginosa

Authors: Khaled Khleifat, Muayyad Abboud, Amjad Khleifat, Humodi Saeed

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In this study, Pseudomonas aeruginosa was isolated from infected burn patients and characterized by standard biochemical tests. The in vitro copper uptake was compared between this isolated pathogenic strain and two non-pathogenic control strains of Gram positive bacteria Bacillusthuringiensis strain Israelisas well as Gram negative bacteria Enterobacter aerogenes. Maximum copper uptake of 470 ppm/g biomass was obtained by P. aeruginosa strain, while the control strains B. thuringiensis andEnterobacter aerogenes had copper uptake of 350 and 383 ppm/g biomass, respectively. However, the lowest copper uptake (60 ppm/g biomass) was observed with another control the saprophytic strain Pseudomonas (Shewanella) putrefaciens. A further investigation regarding the effect of copper toxicity on bacterial growth, gave an MIC score of 600 ppm for P. aeruginosa strain compared to 460 and 300 ppm for the two Gram positive and Gram negative control strains, respectively. In tandem with these in vitro findings, blood analysis on burn patients infected with P. aeruginosa has indicated a selective decrease of copper (hypocupremia) and ceruloplasmin plasma levels. The iron metabolism was also affected by this copper deprivation leading to a similar decrease in plasma levels of PCV, iron, total iron binding capacity, and transferrin. All these hematological changes were significantly different (P < 0.05) from the matched group of non-infected burn patients. The observed hypocupremia in infected burn patients was attributed to demanding scavenger ability by P. aeruginosa strain for the copper of plasma.

Keywords: pseudomonas, Cu uptake, burn patients, biosorption

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5730 Effects of Radiation on Mixed Convection in Power Law Fluids along Vertical Wedge Embedded in a Saturated Porous Medium under Prescribed Surface Heat Flux Condition

Authors: Qaisar Ali, Waqar A. Khan, Shafiq R. Qureshi

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Heat transfer in Power Law Fluids across cylindrical surfaces has copious engineering applications. These applications comprises of areas such as underwater pollution, bio medical engineering, filtration systems, chemical, petroleum, polymer, food processing, recovery of geothermal energy, crude oil extraction, pharmaceutical and thermal energy storage. The quantum of research work with diversified conditions to study the effects of combined heat transfer and fluid flow across porous media has increased considerably over last few decades. The most non-Newtonian fluids of practical interest are highly viscous and therefore are often processed in the laminar flow regime. Several studies have been performed to investigate the effects of free and mixed convection in Newtonian fluids along vertical and horizontal cylinder embedded in a saturated porous medium, whereas very few analysis have been performed on Power law fluids along wedge. In this study, boundary layer analysis under the effects of radiation-mixed convection in power law fluids along vertical wedge in porous medium have been investigated using an implicit finite difference method (Keller box method). Steady, 2-D laminar flow has been considered under prescribed surface heat flux condition. Darcy, Boussinesq and Roseland approximations are assumed to be valid. Neglecting viscous dissipation effects and the radiate heat flux in the flow direction, the boundary layer equations governing mixed convection flow over a vertical wedge are transformed into dimensionless form. The single mathematical model represents the case for vertical wedge, cone and plate by introducing the geometry parameter. Both similar and Non- similar solutions have been obtained and results for Non similar case have been presented/ plotted. Effects of radiation parameter, variable heat flux parameter, wedge angle parameter ‘m’ and mixed convection parameter have been studied for both Newtonian and Non-Newtonian fluids. The results are also compared with the available data for the analysis of heat transfer in the prescribed range of parameters and found in good agreement. Results for the details of dimensionless local Nusselt number, temperature and velocity fields have also been presented for both Newtonian and Non-Newtonian fluids. Analysis of data revealed that as the radiation parameter or wedge angle is increased, the Nusselt number decreases whereas it increases with increase in the value of heat flux parameter at a given value of mixed convection parameter. Also, it is observed that as viscosity increases, the skin friction co-efficient increases which tends to reduce the velocity. Moreover, pseudo plastic fluids are more heat conductive than Newtonian and dilatant fluids respectively. All fluids behave identically in pure forced convection domain.

Keywords: porous medium, power law fluids, surface heat flux, vertical wedge

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5729 Manifestation of Behavioral and Emotional Disturbances and Perceived Coping Strategies of Earthquake Survived Children

Authors: Mahwish Rabia, Najma Najam

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The present study was conducted to identify emotional and behavioral disturbances among earthquake survived children and the perceived coping strategies of affected children. In the present study, a sample of 50 children (6-16 years) belonging to badly affected areas (earthquake) was selected from different camps in Islamabad. Child Behavioral Checklist (CBCL) and Rotter Incomplete Sentence Blank (RISB) interpretations were used to assess variety of emotional and behavioral patterns, and Child Coping Strategies Checklist (CCSC) was used to assess the perceived coping strategies of affected children. Results showed that some of the frequent emotional/behavioral reactions exhibited by children like withdrawal, anxiety\depression, aggression and attention seeking behavior. Whereas gender-based comparisons indicated that female children showed more internalizing behavioral patterns (withdrawn, somatic complaints) as compared to male children who exhibited more externalizing emotions (aggression, delinquent behavior).Coping strategies in which male children tried to adopt Positive Cognitive Restructuring and for distracting attention they used distraction strategies of coping. It is concluded that significant negative emotional and behavioral reactions are exhibited by the earthquake affected children. Male children adopt coping strategies more as compared to female children. The study identifies the negative emotional and behavioral reactions towards trauma, which can be helpful for identifying the problematic area for counseling and therapeutic interventions for these children.

Keywords: behavioural disturbances, emotional disturbances, coping strategies, earthquake, children

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5728 Diet and Exercise Intervention and Bio–Atherogenic Markers for Obesity Classes of Black South Africans with Type 2 Diabetes Mellitus Using Discriminant Analysis

Authors: Oladele V. Adeniyi, B. Longo-Mbenza, Daniel T. Goon

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Background: Lipids are often low or in the normal ranges and controversial in the atherogenesis among Black Africans. The effect of the severity of obesity on some traditional and novel cardiovascular disease risk factors is unclear before and after a diet and exercise maintenance programme among obese black South Africans with type 2 diabetes mellitus (T2DM). Therefore, this study aimed to identify the risk factors to discriminate obesity classes among patients with T2DM before and after a diet and exercise programme. Methods: This interventional cohort of Black South Africans with T2DM was followed by a very – low calorie diet and exercise programme in Mthatha, between August and November 2013. Gender, age, and the levels of body mass index (BMI), blood pressure, monthly income, daily frequency of meals, blood random plasma glucose (RPG), serum creatinine, total cholesterol (TC), triglycerides (TG), LDL –C, HDL – C, Non-HDL, ratios of TC/HDL, TG/HDL, and LDL/HDL were recorded. Univariate analysis (ANOVA) and multivariate discriminant analysis were performed to separate obesity classes: normal weight (BMI = 18.5 – 24.9 kg/m2), overweight (BMI = 25 – 29.9 kg/m2), obesity Class 1 (BMI = 30 – 34.9 kg/m2), obesity Class 2 (BMI = 35 – 39.9 kg/m2), and obesity Class 3 (BMI ≥ 40 kg/m2). Results: At the baseline (1st Month September), all 327 patients were overweight/obese: 19.6% overweight, 42.8% obese class 1, 22.3% obese class 2, and 15.3% obese class 3. In discriminant analysis, only systolic blood pressure (SBP with positive association) and LDL/HDL ratio (negative association) significantly separated increasing obesity classes. At the post – evaluation (3rd Month November), out of all 327 patients, 19.9%, 19.3%, 37.6%, 15%, and 8.3% had normal weight, overweight, obesity class 1, obesity class 2, and obesity class 3, respectively. There was a significant negative association between serum creatinine and increase in BMI. In discriminant analysis, only age (positive association), SBP (U – shaped relationship), monthly income (inverted U – shaped association), daily frequency of meals (positive association), and LDL/HDL ratio (positive association) classified significantly increasing obesity classes. Conclusion: There is an epidemic of diabesity (Obesity + T2DM) in this Black South Africans with some weight loss. Further studies are needed to understand positive or negative linear correlations and paradoxical curvilinear correlations between these markers and increase in BMI among black South African T2DM patients.

Keywords: atherogenic dyslipidaemia, dietary interventions, obesity, south africans

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5727 An Exploratory Study to Investigate the Impact of Corporate Social Responsibility on Luxury Brand Avoidance in India

Authors: Glyn Atwal, Douglas Bryson

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The rapid expansion of a consumer class in India has also coincided with an increasing awareness of social and environmental issues. The overall objective of this study explores to what extent Corporate Social Responsibility (CSR) can lead to luxury brand avoidance within an Indian context. In-depth interviews were conducted with luxury consumers in New Delhi. The demographic breakdown of those interviewed was 16 males and 9 females, aged between 21 and 44. Antecedents of brand avoidance could be sorted according to two main categories. The first category was consumer dissatisfaction due to poor product or service performance. Customer service, particularly within the hospitality sector, was identified as a defining source of brand avoidance. The second category was negative stereotypes of brand users. A salient finding was that no single participant explicitly identified CSR as a source of brand avoidance. However, the interviews revealed that luxury consumers are in fact concerned about CSR issues but assume that international luxury brands have a positive record on CSR performance. Interestingly, participants placed greater emphasis on the broader interpretation of ‘corporate reputation’ rather than specific social or environmental issues to determine the CSR performance of a luxury brand. The findings reported in this exploratory study suggest that Indian luxury consumers do value the overall CSR performance of luxury brands expressed as a brand responsibility or brand reputation, and this is a potential source of brand avoidance. International luxury brands need, therefore, consider developing but also communicating a positive CSR strategy in order to reduce the risk of customers forming negative opinions about the brand.

Keywords: brand avoidance, CSR, luxury

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5726 Intelligent Parking Systems for Quasi-Close Communities

Authors: Ayodele Adekunle Faiyetole, Olumide Olawale Jegede

Abstract:

This paper presents the experimental design and needs justifications for a localized intelligent parking system (L-IPS), ideal for quasi-close communities with increasing vehicular volume that depends on limited or constant parking facilities. For a constant supply in parking facilities, the demand for an increasing vehicular volume could lead to poor time conservation or extended travel time, traffic congestion or impeded mobility, and safety issues. Increased negative environmental and economic externalities are other associated and consequent downsides of disparities in demand and supply. This L-IPS is designed using a microcontroller, ultrasonic sensors, LED indicators, such that the current status, in terms of parking spots availability, can be known from the main entrance to the community or a parking zone on a LCD screen. As an advanced traffic management system (ATMS), the L-IPS is designed to resolve aspects of infrastructure-to-driver (I2D) communication and parking detection issues. Thus, this L-IPS can act as a timesaver for users by helping them know the availability of parking spots. Providing on-time, informed routing, to a next preference or seamless moving to berth on the available spot on a proximate facility as the case may be. Its use could also increase safety and increase mobility, and fuel savings and costs, therefore, reducing negative environmental and economic externalities due to transportation systems.

Keywords: intelligent parking systems, localized intelligent parking system, intelligent transport systems, advanced traffic management systems, infrastructure-to-drivers communication

Procedia PDF Downloads 171
5725 Study on the Effect of Weather Variables on the Spider Abundance in Two Ecological Zones of Ogun State, Nigeria

Authors: Odejayi Adedayo Olugbenga, Aina Adebisi

Abstract:

Weather variables (rainfall and temperature) affect the diversity and abundance of both fauna and flora species. This study compared the weather variables with spider abundance in two ecological zones of Ogun State, Nigeria namely Ago-iwoye (Rainforest) in the Ijebu axis and Aiyetoro (Derived Savannah) in the Yewa axis. Seven study sites chosen by Simple Random Sampling in each ecosystem were used for the study. In each sampling area, a 60 m x 120 m land area was marked and sampled, spider collection techniques were; hand picking, use of sweep netting, and Pitfall trap. Adult spiders were identified to the species level. Species richness was estimated by a non-parametric species estimator while the diversity of spider species was assessed by Simpson Diversity Index and Species Richness by One-way Analysis of Variance. Results revealed that spiders were more abundant in rainforest zones than in derived savannah ecosystems. However, the pattern of spider abundance in rainforest zone and residential areas were similar. During high temperatures, the activities of spiders tended to increase according to this study. In contrast, results showed that there was a negative correlation between rainfall and spider species abundance in addition to a negative and weak correlation between rainfall and species richness. It was concluded that heavy downpour has lethal effects on both immature and sometimes matured spiders, which could lead to the extinction of some unknown species of spiders. Tree planting should be encouraged, as this shelters the spider.

Keywords: spider, abundance, species richness, species diversity

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5724 Modeling and Design of a Solar Thermal Open Volumetric Air Receiver

Authors: Piyush Sharma, Laltu Chandra, P. S. Ghoshdastidar, Rajiv Shekhar

Abstract:

Metals processing operations such as melting and heat treatment of metals are energy-intensive, requiring temperatures greater than 500oC. The desired temperature in these industrial furnaces is attained by circulating electrically-heated air. In most of these furnaces, electricity produced from captive coal-based thermal power plants is used. Solar thermal energy could be a viable heat source in these furnaces. A retrofitted solar convective furnace (SCF) concept, which uses solar thermal generated hot air, has been proposed. Critical to the success of a SCF is the design of an open volumetric air receiver (OVAR), which can heat air in excess of 800oC. The OVAR is placed on top of a tower and receives concentrated solar radiation from a heliostat field. Absorbers, mixer assembly, and the return air flow chamber (RAFC) are the major components of an OVAR. The absorber is a porous structure that transfers heat from concentrated solar radiation to ambient air, referred to as primary air. The mixer ensures uniform air temperature at the receiver exit. Flow of the relatively cooler return air in the RAFC ensures that the absorbers do not fail by overheating. In an earlier publication, the detailed design basis, fabrication, and characterization of a 2 kWth open volumetric air receiver (OVAR) based laboratory solar air tower simulator was presented. Development of an experimentally-validated, CFD based mathematical model which can ultimately be used for the design and scale-up of an OVAR has been the major objective of this investigation. In contrast to the published literature, where flow and heat transfer have been modeled primarily in a single absorber module, the present study has modeled the entire receiver assembly, including the RAFC. Flow and heat transfer calculations have been carried out in ANSYS using the LTNE model. The complex return air flow pattern in the RAFC requires complicated meshes and is computational and time intensive. Hence a simple, realistic 1-D mathematical model, which circumvents the need for carrying out detailed flow and heat transfer calculations, has also been proposed. Several important results have emerged from this investigation. Circumferential electrical heating of absorbers can mimic frontal heating by concentrated solar radiation reasonably well in testing and characterizing the performance of an OVAR. Circumferential heating, therefore, obviates the need for expensive high solar concentration simulators. Predictions suggest that the ratio of power on aperture (POA) and mass flow rate of air (MFR) is a normalizing parameter for characterizing the thermal performance of an OVAR. Increasing POA/MFR increases the maximum temperature of air, but decreases the thermal efficiency of an OVAR. Predictions of the 1-D mathematical are within 5% of ANSYS predictions and computation time is reduced from ~ 5 hours to a few seconds.

Keywords: absorbers, mixer assembly, open volumetric air receiver, return air flow chamber, solar thermal energy

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5723 CFD Study for Normal and Rifled Tube with a Convergence Check

Authors: Sharfi Dirar, Shihab Elhaj, Ahmed El Fatih

Abstract:

Computational fluid dynamics were used to simulate and study the heated water boiler tube for both normal and rifled tube with a refinement of the mesh to check the convergence. The operation condition was taken from GARRI power station and used in a boundary condition accordingly. The result indicates the rifled tube has higher heat transfer efficiency than the normal tube.

Keywords: boiler tube, convergence check, normal tube, rifled tube

Procedia PDF Downloads 334
5722 Three Dimensional Large Eddy Simulation of Blood Flow and Deformation in an Elastic Constricted Artery

Authors: Xi Gu, Guan Heng Yeoh, Victoria Timchenko

Abstract:

In the current work, a three-dimensional geometry of a 75% stenosed blood vessel is analysed. Large eddy simulation (LES) with the help of a dynamic subgrid scale Smagorinsky model is applied to model the turbulent pulsatile flow. The geometry, the transmural pressure and the properties of the blood and the elastic boundary were based on clinical measurement data. For the flexible wall model, a thin solid region is constructed around the 75% stenosed blood vessel. The deformation of this solid region was modelled as a deforming boundary to reduce the computational cost of the solid model. Fluid-structure interaction is realised via a two-way coupling between the blood flow modelled via LES and the deforming vessel. The information of the flow pressure and the wall motion was exchanged continually during the cycle by an arbitrary lagrangian-eulerian method. The boundary condition of current time step depended on previous solutions. The fluctuation of the velocity in the post-stenotic region was analysed in the study. The axial velocity at normalised position Z=0.5 shows a negative value near the vessel wall. The displacement of the elastic boundary was concerned in this study. In particular, the wall displacement at the systole and the diastole were compared. The negative displacement at the stenosis indicates a collapse at the maximum velocity and the deceleration phase.

Keywords: Large Eddy Simulation, Fluid Structural Interaction, constricted artery, Computational Fluid Dynamics

Procedia PDF Downloads 293
5721 Similitude for Thermal Scale-up of a Multiphase Thermolysis Reactor in the Cu-Cl Cycle of a Hydrogen Production

Authors: Mohammed W. Abdulrahman

Abstract:

The thermochemical copper-chlorine (Cu-Cl) cycle is considered as a sustainable and efficient technology for a hydrogen production, when linked with clean-energy systems such as nuclear reactors or solar thermal plants. In the Cu-Cl cycle, water is decomposed thermally into hydrogen and oxygen through a series of intermediate reactions. This paper investigates the thermal scale up analysis of the three phase oxygen production reactor in the Cu-Cl cycle, where the reaction is endothermic and the temperature is about 530 oC. The paper focuses on examining the size and number of oxygen reactors required to provide enough heat input for different rates of hydrogen production. The type of the multiphase reactor used in this paper is the continuous stirred tank reactor (CSTR) that is heated by a half pipe jacket. The thermal resistance of each section in the jacketed reactor system is studied to examine its effect on the heat balance of the reactor. It is found that the dominant contribution to the system thermal resistance is from the reactor wall. In the analysis, the Cu-Cl cycle is assumed to be driven by a nuclear reactor where two types of nuclear reactors are examined as the heat source to the oxygen reactor. These types are the CANDU Super Critical Water Reactor (CANDU-SCWR) and High Temperature Gas Reactor (HTGR). It is concluded that a better heat transfer rate has to be provided for CANDU-SCWR by 3-4 times than HTGR. The effect of the reactor aspect ratio is also examined in this paper and is found that increasing the aspect ratio decreases the number of reactors and the rate of decrease in the number of reactors decreases by increasing the aspect ratio. Finally, a comparison between the results of heat balance and existing results of mass balance is performed and is found that the size of the oxygen reactor is dominated by the heat balance rather than the material balance.

Keywords: sustainable energy, clean energy, Cu-Cl cycle, heat transfer, hydrogen, oxygen

Procedia PDF Downloads 296
5720 YHV-Responsive Gene Expression under the Influence of PmRelish Regulation

Authors: Suwattana Visetnan, Premruethai Supungul, Sureerat Tang, Ikuo Hirono, Anchalee Tassanakajon, Vichien Rimphanitchayakit

Abstract:

In animals, infection by Gram-negative bacteria and certain viruses activates the Imd signaling pathway wherein the a NF-κB transcription factor, Relish, is a key regulatory protein for the synthesis of antimicrobial proteins. Infection by yellow head virus (YHV) activates the Imd pathway. To investigate the expression of genes involved in YHV infection and under the influence of PmRelish regulation, RNA interference and suppression subtractive hybridization (SSH) are employed. The genes in forward library expressed in shrimp after YHV infection and under the activity of PmRelish were obtained by subtracting the cDNAs from YHV-infected and PmRelish-knockdown shrimp with cDNAs from YHV-infected shrimp. Opposite subtraction gave a reverse library whereby an alternative set of genes under YHV infection and no PmRelish expression was obtained. Sequencing of 252 and 99 cDNA clones from the respective forward and reverse libraries were done and annotated through blast search against the GenBank sequences. Genes involved in defense and homeostasis were abundant in both libraries, 31% and 23% in the forward and reverse libraries, respectively. They were predominantly antimicrobial proteins, proteinases and proteinase inhibitors. The expression of antimicrobial protein genes, ALFPm3, crustinPm1, penaeidin3 and penaeidin5 were tested under PmRelish silencing and Gram-negative bacterium V. harveyi infection. Together with the results previously reported, the expression of penaeidin5 and also penaeidin3 but not ALFPm3 and crustinPm1 were under the regulation of PmRelish in the Imd pathway.

Keywords: relish, yellow head virus, penaeus monodon, antimicrobial proteins

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5719 Investigating the Combined Medicinal Effects of Withania Somnifera (Ashwaghandha) and Murraya Koenigii (Curry Pata) in Vitro

Authors: Sadia Roshan, Kulsoom Sughra, Shazia Shamas, Shamaila Irum, Haleema Sadia

Abstract:

To evaluate synergistic medicinal effects of Withania somnifera (Ashwaghandha) and Murraya koenigii (Curry pata) in vitro. Antimicrobial activity was determined using the disc diffusion method against five bacterial and two fungal strains. The antioxidant activity was evaluated by the DPPH assay. The antidiabetic activity was evaluated by alpha-glucosidase inhibition assay and alpha-amylase inhibition assay. Synergistic antibacterial activity was observed against all the strains of bacteria, either Gram-positive or Gram-negative and fungi under study conditions. The maximum antibacterial activity was displayed by combined extract against E. coli i.e. 26±0.4mm. Maximum antifungal activity was shown by combined extract against Aspergillus niger, i.e., 17.3±0.5mm. The antioxidant activity of the combined extract was also significant. Alpha-glucosidase inhibition and alpha-amylase inhibition assays also showed synergism. Results indicate that Withania somnifera and Murraya koengii have medicinal properties. The combined extract of both plants is more potent than their individual extracts, suggesting that these can work in synergism. The research suggests that different plant extracts could be used in combination to increase their medicinal activities by many folds, thus giving an insight into future use of herbal medication.

Keywords: withania somnifera, murraya koenigii, antimicrobial activity, gram-positive bacetria, gram-negative bacteria

Procedia PDF Downloads 79
5718 Discursive Legitimation Strategies in ISIS’ Online Magazine, Dabiq: A Discourse Historical Approach

Authors: Sahar Rasoulikolamaki

Abstract:

ISIS (also known as DAASH) is an Islamic fundamentalist group that has been known as a global threat to the whole world for their radicalizing approach and application of online platforms as a tool to portray their activities, to disseminate their ideology, and to commit recruiting activities. This study is an attempt to carry out a critical discourse analysis on the argumentative devices by which ISIS legitimizes or delegitimizes positive or negative constructions of social practices in Dabiq. It tries to shed light on how texts in Dabiq as linguistic elements in the micro level of analysis relate to ISIS’ ideology as the higher-up macro level and in other words, how local structures contributed to the construction and transference of a global structure or ideology and vice versa. Therefore, following the relevant analytical frameworks, the study focuses on both micro-level of analysis of arguments (topoi) and macro-structure of legitimation and delegitimation in Dabiq. This purpose is nailed using the analytical categories and tools provided by Wodak’s Discourse Historical Approach (DHA) such as argumentation strategies (topoi), by which the coded language of legitimation/delegitimation and persuasion as used in Dabiq are explored. The ensuing findings demonstrate that Dabiq rigorously relies on the positive representation of the in-group course of actions and justifying its violence and, at the same time, the negative representation of the out-group behavior through implementing various topoi to achieve its desired outcome, which is the ideological manipulation and powerful self-depiction, as well as the supporter recruitment.

Keywords: argumentation, discourse-historical approach, ideology, legitimation and delegitimation, topoi

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5717 Corporate Voluntary Greenhouse Gas Emission Reporting in United Kingdom: Insights from Institutional and Upper Echelons Theories

Authors: Lyton Chithambo

Abstract:

This paper reports the results of an investigation into the extent to which various stakeholder pressures influence voluntary disclosure of greenhouse-gas (GHG) emissions in the United Kingdom (UK). The study, which is grounded on institutional theory, also borrows from the insights of upper echelons theory and examines whether specific managerial (chief executive officer) characteristics explain and moderates various stakeholder pressures in explaining GHG voluntary disclosure. Data were obtained from the 2011 annual and sustainability reports of a sample of 216 UK companies on the FTSE350 index listed on the London Stock Exchange. Generally the results suggest that there is no substantial shareholder and employee pressure on a firm to disclose GHG information but there is significant positive pressure from the market status of a firm with those firms with more market share disclosing more GHG information. Consistent with the predictions of institutional theory, we found evidence that coercive pressure i.e. regulatory pressure and mimetic pressures emanating in some industries notably industrials and consumer services have a significant positive influence on firms’ GHG disclosure decisions. Besides, creditor pressure also had a significant negative relationship with GHG disclosure. While CEO age had a direct negative effect on GHG voluntary disclosure, its moderation effect on stakeholder pressure influence on GHG disclosure was only significant on regulatory pressure. The results have important implications for both policy makers and company boards strategizing to reign in their GHG emissions.

Keywords: greenhouse gases, voluntary disclosure, upper echelons theory, institution theory

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5716 Spatial Differentiation Patterns and Influencing Mechanism of Urban Greening in China: Based on Data of 289 Cities

Authors: Fangzheng Li, Xiong Li

Abstract:

Significant differences in urban greening have occurred in Chinese cities, which accompanied with China's rapid urbanization. However, few studies focused on the spatial differentiation of urban greening in China with large amounts of data. The spatial differentiation pattern, spatial correlation characteristics and the distribution shape of urban green space ratio, urban green coverage rate and public green area per capita were calculated and analyzed, using Global and Local Moran's I using data from 289 cities in 2014. We employed Spatial Lag Model and Spatial Error Model to assess the impacts of urbanization process on urban greening of China. Then we used Geographically Weighted Regression to estimate the spatial variations of the impacts. The results showed: 1. a significant spatial dependence and heterogeneity existed in urban greening values, and the differentiation patterns were featured by the administrative grade and the spatial agglomeration simultaneously; 2. it revealed that urbanization has a negative correlation with urban greening in Chinese cities. Among the indices, the the proportion of secondary industry, urbanization rate, population and the scale of urban land use has significant negative correlation with the urban greening of China. Automobile density and per capita Gross Domestic Product has no significant impact. The results of GWR modeling showed that the relationship between urbanization and urban greening was not constant in space. Further, the local parameter estimates suggested significant spatial variation in the impacts of various urbanization factors on urban greening.

Keywords: China’s urbanization, geographically weighted regression, spatial differentiation pattern, urban greening

Procedia PDF Downloads 461
5715 Biodegradable Polymer Film Incorporated with Polyphenols for Active Packaging

Authors: Shubham Sharma, Swarna Jaiswal, Brendan Duffy, Amit Jaiswal

Abstract:

The key features of any active packaging film are its biodegradability and antimicrobial properties. Biological macromolecules such as polyphenols (ferulic acid (FA) and tannic acids (TA)) are naturally found in plants such as grapes, berries, and tea. In this study, antimicrobial activity screening of several polyphenols was carried out by using minimal inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) against two strains of gram-negative bacteria - Salmonella typhimurium, Escherichia coli, and two-gram positive strains - Staphylococcus aureus and Listeria monocytogenes. FA and TA had shown strong antibacterial activity at the low concentration against both gram-positive and gram-negative bacteria. The selected polyphenols FA and TA were incorporated at various concentrations (1%, 5%, and 10% w/w) in the poly(lactide) – poly (butylene adipate-co-terephthalate) (PLA-PBAT) composite film by using the solvent casting method. The effect of TA and FA incorporation in the packaging was characterized based on morphological, optical, color, mechanical, thermal, and antimicrobial properties. The thickness of the FA composite film was increased by 1.5 – 7.2%, while for TA composite film, it increased by 0.018 – 1.6%. FA and TA (10 wt%) composite film had shown approximately 65% - 66% increase in the UV barrier property. As the FA and TA concentration increases from 1% - 10% (w/w), the TS value increases by 1.98 and 1.80 times, respectively. The water contact angle of the film was observed to decrease significantly with the increase in the FA and TA content in the composite film. FA has shown more significant increase in antimicrobial activity than TA in the composite film against Listeria monocytogenes and E. coli. The FA and TA composite film has the potential for its application as an active food packaging.

Keywords: active packaging, biodegradable film, polyphenols, UV barrier, tensile strength

Procedia PDF Downloads 152