Search results for: negative space
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 8124

Search results for: negative space

2454 Maintaining Experimental Consistency in Geomechanical Studies of Methane Hydrate Bearing Soils

Authors: Lior Rake, Shmulik Pinkert

Abstract:

Methane hydrate has been found in significant quantities in soils offshore within continental margins and in permafrost within arctic regions where low temperature and high pressure are present. The mechanical parameters for geotechnical engineering are commonly evaluated in geomechanical laboratories adapted to simulate the environmental conditions of methane hydrate-bearing sediments (MHBS). Due to the complexity and high cost of natural MHBS sampling, most laboratory investigations are conducted on artificially formed samples. MHBS artificial samples can be formed using different hydrate formation methods in the laboratory, where methane gas and water are supplied into the soil pore space under the methane hydrate phase conditions. The most commonly used formation method is the excess gas method which is considered a relatively simple, time-saving, and repeatable testing method. However, there are several differences in the procedures and techniques used to produce the hydrate using the excess gas method. As a result of the difference between the test facilities and the experimental approaches that were carried out in previous studies, different measurement criteria and analyses were proposed for MHBS geomechanics. The lack of uniformity among the various experimental investigations may adversely impact the reliability of integrating different data sets for unified mechanical model development. In this work, we address some fundamental aspects relevant to reliable MHBS geomechanical investigations, such as hydrate homogeneity in the sample, the hydrate formation duration criterion, the hydrate-saturation evaluation method, and the effect of temperature measurement accuracy. Finally, a set of recommendations for repeatable and reliable MHBS formation will be suggested for future standardization of MHBS geomechanical investigation.

Keywords: experimental study, laboratory investigation, excess gas, hydrate formation, standardization, methane hydrate-bearing sediment

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2453 Recovery from Detrimental pH Troughs in a Moorland River Using Monitored Calcium Carbonate Introductions

Authors: Lauren Dawson, Sean Comber, Richard Sandford, Alan Tappin, Bruce Stockley

Abstract:

The West Dart River is underperforming for Salmon (Salmo salar) survival rates due to acidified pH troughs under the European Water Framework Directive (2000/60/EC). These troughs have been identified as being caused by historic acid rain pollution which is being held in situ by peat bog presence at site and released during flushing events. Natural recovery has been deemed unlikely by the year 2020 using steady state water chemistry models and therefore a program of monitored calcium carbonate (CaCO3) introductions are being conducted to eliminate these troughs, which can drop to pH 2.93 (salmon survival – pH 5.5). The river should be naturally acidic (pH 5.5-6) due to the granite geology of Dartmoor and therefore the CaCO3 introductions are under new methodology (the encasing of the CaCO3 in permeable sacks) to ensure removal should the water pH rise above neutral levels. The water chemistry and ecology are undergoing comprehensive monitoring, including pH and turbidity levels, dissolved organic carbon and aluminum concentration and speciation, while the aquatic biota is being used to assess the potential water chemistry changes. While this project is ongoing, results from the preliminary field trial show only a temporary, localized increase in pH following CaCO3 introductions into the water column. However, changes to the water chemistry have only been identified in the West Dart after methodology adjustments to account for flow rates and spate-dissolution, though no long-term changes have so far been found in the ecology of the river. However, this is not necessarily a negative factor, as the aim of the study is to protect the current ecological communities and the natural pH of the river while remediating only the detrimental pH troughs.

Keywords: anthropogenic acidification recovery, calcium carbonate introductions, ecology monitoring, water chemistry monitoring

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2452 Length/Length-Length/Weight Relationships for 2 Erythrean mantis Shrimp Species, Erugosquilla massavensis (Kossmann, 1883), and Clorida albolitura (Ahyong&Naiyanetr, 2000) from the Yumurtalik Cove, Northeastern Mediterranean of Turkey

Authors: Canan Türeli̇, İrem Nur Yeşi̇lyurt

Abstract:

A total of nine stomatopod crustaceans have been reported from the eastern Mediterranean, with the eight from the Turkey coasts and three from the Levantine coast of Turkey (Squilla massavensis (Linnaeus,1758), Erugosquilla massavensis (Kossmann, 1880), Clorida albolitura (Ahyong&Naiyanetr, 2000). E. massavensis is the most successful Red Sea immigrant, and it is now the dominant eastern Levantine stomatopod. At this research, carapace length/total length- weight relationship of 2 erythrean mantis shrimp, E. massavensis and C. albolitura was studied in Yumurtalık Cove, in the Northeastern Mediterranean of Turkey. Samples were collected monthly from July 2014 to June 2015 (except February), using bottom trawl net into three different depth strata; 0- 10 m, 10-20 m, 20-50m. E. massavensis samples were caught all studied time, except winter, in the three depth range but C. albolitura samples were caught only in July, October and May's months. A total of 572 specimens of the E. massavensis and 12 specimens of the C. albolitura were collected and analyzed. Morphometric equations for the conversions of total length and weight, carapace lengths were constructed for males, females, combined sexes for E. massavensis and C. albolitura. The b-values for total length (TL)-weight (W) in males and females for E. massavensis were 2.738 and 2.725 respectively and for carapace length (CL)-total length (TL) they were 1.041 and 0.978, relatively. The b-values (total length-weight) were determined for combined sexes of E. massavensis and C. albolitura as: 2.771, 1.852 relatively. In both species, the relative growth of weight and total length was found highly positively allometric. However, carapace length showed negative allometry in females of E. Massavensis.

Keywords: Clorida albolitura, Erugosquilla massavensis, Erythrean stomatopod, length/length-weight relationships

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2451 Lightweight and Seamless Distributed Scheme for the Smart Home

Authors: Muhammad Mehran Arshad Khan, Chengliang Wang, Zou Minhui, Danyal Badar Soomro

Abstract:

Security of the smart home in terms of behavior activity pattern recognition is a totally dissimilar and unique issue as compared to the security issues of other scenarios. Sensor devices (low capacity and high capacity) interact and negotiate each other by detecting the daily behavior activity of individuals to execute common tasks. Once a device (e.g., surveillance camera, smart phone and light detection sensor etc.) is compromised, an adversary can then get access to a specific device and can damage daily behavior activity by altering the data and commands. In this scenario, a group of common instruction processes may get involved to generate deadlock. Therefore, an effective suitable security solution is required for smart home architecture. This paper proposes seamless distributed Scheme which fortifies low computational wireless devices for secure communication. Proposed scheme is based on lightweight key-session process to upheld cryptic-link for trajectory by recognizing of individual’s behavior activities pattern. Every device and service provider unit (low capacity sensors (LCS) and high capacity sensors (HCS)) uses an authentication token and originates a secure trajectory connection in network. Analysis of experiments is revealed that proposed scheme strengthens the devices against device seizure attack by recognizing daily behavior activities, minimum utilization memory space of LCS and avoids network from deadlock. Additionally, the results of a comparison with other schemes indicate that scheme manages efficiency in term of computation and communication.

Keywords: authentication, key-session, security, wireless sensors

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2450 The Role and Significance of Mobile Gerdarmarie Battalions in the Canakkale Battles

Authors: Muzaffer Topgül, Ersi̇n Yilmaz

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One of the unknown aspects of Çanakkale Battles is that the importance and contributions of Mobile Gendarmarie Battalion have not been fully understood. It was because the battles of the troops which were deployed more in interior parts of Gallipoli Peninsula, and the contributions of battle on level tactical troops were not considered as much as the studies on strategical or operative level troops. When the operation field and battle plans are examined, instead of deploying along the coast to put the forces with a power at zero level landing on the coast out of action, the main battle components are seen to have deployed as strong reserves in the more inner areas. The negative effect of the field on the great trop operation reveals the need for time in order to use the intervention forces. ‘Time’ emerged as the main factor in victory as a result of giving intervention opportunity to the troops. While ordering his soldiers in Conkbayırı to die rather than fight, Liutenant Colonel Mustafa Kemal, the Commander of the 19th division, also emphasized the significance of time. In this respect, the contribution of Mobile Gendarmarie Battalion which saved time for the troops to intervene can be clearly seen. During the study, the memoirs and the works written by military institutions based on the record sources under the light of the notes taken during the trips to the region were used. By preventing the enemies from capturing the area, Mobile Gendarmerie Battalions had an important role in Battles of Kerevizdere, Kireçtepe and Alçıtepe which were of great importance among the battles. The success of these battalions was expressed with compliment by both Turkish and foreign commanders that participated in the war. During the battles the losses of armed forces commissioned to keep the security and order brought about the formation of the regions deficient in state authority.

Keywords: Canakkale battles, mustafa kemal, mobile gerdarmarie, Ottoman empire, time

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2449 A Knowledge-Based Development of Risk Management Approaches for Construction Projects

Authors: Masoud Ghahvechi Pour

Abstract:

Risk management is a systematic and regular process of identifying, analyzing and responding to risks throughout the project's life cycle in order to achieve the optimal level of elimination, reduction or control of risk. The purpose of project risk management is to increase the probability and effect of positive events and reduce the probability and effect of unpleasant events on the project. Risk management is one of the most fundamental parts of project management, so that unmanaged or untransmitted risks can be one of the primary factors of failure in a project. Effective risk management does not apply to risk regression, which is apparently the cheapest option of the activity. However, the main problem with this option is the economic sensitivity, because what is potentially profitable is by definition risky, and what does not pose a risk is economically interesting and does not bring tangible benefits. Therefore, in relation to the implemented project, effective risk management is finding a "middle ground" in its management, which includes, on the one hand, protection against risk from a negative direction by means of accurate identification and classification of risk, which leads to analysis And it becomes a comprehensive analysis. On the other hand, management using all mathematical and analytical tools should be based on checking the maximum benefits of these decisions. Detailed analysis, taking into account all aspects of the company, including stakeholder analysis, will allow us to add what will become tangible benefits for our project in the future to effective risk management. Identifying the risk of the project is based on the theory that which type of risk may affect the project, and also refers to specific parameters and estimating the probability of their occurrence in the project. These conditions can be divided into three groups: certainty, uncertainty, and risk, which in turn support three types of investment: risk preference, risk neutrality, specific risk deviation, and its measurement. The result of risk identification and project analysis is a list of events that indicate the cause and probability of an event, and a final assessment of its impact on the environment.

Keywords: risk, management, knowledge, risk management

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2448 Effect of Short-Term Enriching of Algae with Selenium and Zinc on Growth and Mineral Composition of Marine Rotifer

Authors: Sirwe Ghaderpour, Nasrollah Ahmadifard, Naser Agh, Zakaria Vahabzadeh

Abstract:

Rotifers are used in many hatcheries for feeding the earliest stages of fish larvae and crustaceans due to their small size, slow movements, fast reproduction, and easy cultivation. One of the disadvantages of using rotifers as live prey is their lower content of some nutrients compared to copepods, so it is necessary to increase the amounts of these nutrients by means of enrichment. Minerals are a group of micro-elements, essential to fish, that is lacking in the rotifers, for example, selenium (30 fold) and zinc (5 fold) are present in lower quantities than the minimum amounts found in copepods. In this study, the condensed Isochrysis aff. galbana (T-ISO) and Nannochloropsis oculata were suspended at concentration of 18 × 109 cell mL⁻¹ of water with 20 ppt of salinity. Four different levels (0, 1000, 2000, and 4000 mg L⁻¹) of each Na₂SeO₃ and ZnSO₄.7H₂O separately were prepared, and 1 mL of each stock was poured to the algae enrichment vessels for 1 h simultaneously. After that, the material was centrifuged (at 4000 rpm for 5 min), and the precipitated enriched algae was used for rotifer feeding. The contents of Se, Zn, Cu, and Mn were determined in enriched microalgae and rotifer by Atomic absorption. The highest content of both minerals was observed in 0.4 Zn + 0.4 Se treatment and also rotifer enriched with these enriched microalgae. The enrichment of microalgae with Zn and Se does not affect the content of Cu in the microalgae. Also, the content of Cu in rotifer fed with the enriched microalgae showed the highest Cu content in the treatments than the control. But, the enrichment with both minerals had a negative effect on the content Mn in enriched mixed microalgae except 0.4 Zn + 0.4 Se. The Mn content in enriched rotifer decreased in the treatments than the control except for 0.1 Zn + 0.1 Se. There was no significant effect on rotifer growth in combined enrichment with both minerals (p < 0.05). Overall, rotifers enrichment with Se and Zn mixed microalgae resulted in increasing Se, Zn, and Cu. This will allow Se and Zn microalgae enriched rotifers to be used as the minerals delivery method for fish larvae nutritional requirements.

Keywords: enrichment, larvae, microalgae, mineral, rotifer

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2447 Acne Vulgaris Association with Smoking and Body Mass Index in Jordanian Young Adults

Authors: Almutazballlah Bassam Qablan, Jihan M. Muhaidat, bana Abu Rajab

Abstract:

Background: Acne vulgaris is considered one of the most common skin conditions encountered by dermatologists. It is a chronic inflammation affecting the pilosebaceous unit. Although acne vulgaris is not fatal, it leads to permanent scarring and disfigurement, and even without scarring, it has a huge effect on patients, causing negative health outcomes. Acne vulgaris patients experience psychological, and emotional ramifications as those with chronic health problems; they feel depressed, angry, anxious, and confused. Although acne is a popular disease, many thoughts and myths are still discussed about its origins and triggering factors. These myths can make you feel guilt as if you were somehow responsible for your acne. In this case control study, we want to define the relationship between two modifiable risk factors ;BMI and smoking, with acne vulgaris. Methods: A case-control study was conducted at King Abdullah University Hospital in Ramtha, Jordan in 2019/2020. A total number of 325 participants between 14 and 33 years of age were interviewed by the authors; including 163 acne vulgaris cases and 162 controls without acne vulgaris. Anthropometric measures and smoking for Acne patients and control participants were the independent variables used to assess acne. Univariate and multivariate analysis were used to compare the characteristics of people who reported acne with those with no acne. The collected data analyzed by using the Statistical Package for Social Sciences (SPSS). Results: Cigarette smoking was highly associated with controls; odds ratio 0.4 (95% CI: 0.2–0.9) , P-value = 0.018. BMI and waterpipe smoking were statistically insignificant with acne in the multivariate analysis. Conclusion: We found that cigarette smoking was protective against Acne. There was a statistically insignificant relation between BMI, waterpipe smoking and the development of Acne Vulgaris.

Keywords: acne, adolescents, BMI, smoking, case-control, risk factors

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2446 Predicting Stem Borer Density in Maize Using RapidEye Data and Generalized Linear Models

Authors: Elfatih M. Abdel-Rahman, Tobias Landmann, Richard Kyalo, George Ong’amo, Bruno Le Ru

Abstract:

Maize (Zea mays L.) is a major staple food crop in Africa, particularly in the eastern region of the continent. The maize growing area in Africa spans over 25 million ha and 84% of rural households in Africa cultivate maize mainly as a means to generate food and income. Average maize yields in Sub Saharan Africa are 1.4 t/ha as compared to global average of 2.5–3.9 t/ha due to biotic and abiotic constraints. Amongst the biotic production constraints in Africa, stem borers are the most injurious. In East Africa, yield losses due to stem borers are currently estimated between 12% to 40% of the total production. The objective of the present study was therefore to predict stem borer larvae density in maize fields using RapidEye reflectance data and generalized linear models (GLMs). RapidEye images were captured for a test site in Kenya (Machakos) in January and in February 2015. Stem borer larva numbers were modeled using GLMs assuming Poisson (Po) and negative binomial (NB) distributions with error with log arithmetic link. Root mean square error (RMSE) and ratio prediction to deviation (RPD) statistics were employed to assess the models performance using a leave one-out cross-validation approach. Results showed that NB models outperformed Po ones in all study sites. RMSE and RPD ranged between 0.95 and 2.70, and between 2.39 and 6.81, respectively. Overall, all models performed similar when used the January and the February image data. We conclude that reflectance data from RapidEye data can be used to estimate stem borer larvae density. The developed models could to improve decision making regarding controlling maize stem borers using various integrated pest management (IPM) protocols.

Keywords: maize, stem borers, density, RapidEye, GLM

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2445 Si Doped HfO₂ Anti-Ferroelectric Thin Films for Energy Storage and Solid State Cooling Applications

Authors: Faizan Ali, Dayu Zhou, Xiaohua Liu, Tony Schenk, Johannes Muller, Uwe Schroeder

Abstract:

Recently, the ferroelectricity (FE) and anti-ferroelectricity (AFE) introduced in so-called 'high-k dielectric' HfO₂ material incorporated with various dopants (Si, Gd, Y, Sr, Gd, Al, and La, etc.), HfO₂-ZrO₂ solid-solution, Al or Si-doped Hf₀.₅Zr₀.₅O₂ and even undoped HfO₂ thin films. The origin of FE property was attributed to the formation of a non-centrosymmetric orthorhombic (o) phase of space group Pbc2₁. To the author’s best knowledge, AFE property was observed only in HfO₂ doped with a certain amount of Si, Al, HfₓZr₁₋ₓO₂ (0 ≤ x < 0.5), and in Si or Al-doped Hf₀.₅Zr₀.₅O₂. The origin of the anti-ferroelectric behavior is an electric field induced phase transition between the non-polar tetragonal (t) and the polar ferroelectric orthorhombic (o) phase. Compared with the significant amount of studies for the FE properties in the context of non-volatile memories, AFE properties of HfO₂-based and HfₓZr₁₋ₓO₂ (HZO) thin films have just received attention recently for energy-related applications such as electrocaloric cooling, pyroelectric energy harvesting, and electrostatic energy storage. In this work, energy storage and solid state cooling properties of Si-doped HfO₂ AFE thin films are investigated. Owing to the high field-induced polarization and slim double hysteresis, an extremely large Energy storage density (ESD) value of 61.2 J cm⁻³ is achieved at 4.5 MV cm⁻¹ with high efficiency of ~65%. In addition, the ESD and efficiency exhibit robust thermal stability in 210-400 K temperature range and excellent endurance up to 10⁹ times of charge/discharge cycling at a very high electric field of 4.0 MV cm⁻¹. Similarly, for solid-state cooling, the maximum adiabatic temperature change (

Keywords: thin films, energy storage, endurance, solid state cooling, anti-ferroelectric

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2444 Pros and Cons of Nanoparticles on Health

Authors: Amber Shahi, Ayesha Tazeen, Abdus Samad, Shama Parveen

Abstract:

Nanoparticles (NPs) are tiny particles. According to the International Organization for Standardization, the size range of NPs is in the nanometer range (1-100 nm). They show distinct properties that are not shown by larger particles of the same material. NPs are currently being used in different fields due to their unique physicochemical nature. NPs are a boon for medical sciences, environmental sciences, electronics, and textile industries. However, there is growing concern about their potential adverse effects on human health. This poster presents a comprehensive review of the current literature on the pros and cons of NPs on human health. The poster will discuss the various types of interactions of NPs with biological systems. There are a number of beneficial uses of NPs in the field of health and environmental welfare. NPs are very useful in disease diagnosis, antimicrobial action, and the treatment of diseases like Alzheimer’s. They can also cross the blood-brain barrier, making them capable of treating brain diseases. Additionally, NPs can target specific tumors and be used for cancer treatment. To treat environmental health, NPs also act as catalytic converters to reduce pollution from the environment. On the other hand, NPs also have some negative impacts on the human body, such as being cytotoxic and genotoxic. They can also affect the reproductive system, such as the testis and ovary, and sexual behavior. The poster will further discuss the routes of exposure of NPs. The poster will conclude with a discussion of the current regulations and guidelines on the use of NPs in various applications. It will highlight the need for further research and the development of standardized toxicity testing methods to ensure the safe use of NPs in various applications. When using NPs in diagnosis and treatment, we should also take into consideration their safe concentration in the body. Overall, this poster aims to provide a comprehensive overview of the pros and cons of NPs on human health and to promote awareness and understanding of the potential risks and benefits associated with their use.

Keywords: disease diagnosis, human health, nanoparticles, toxicity testing

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2443 Effects of Climate Change and Land Use, Land Cover Change on Atmospheric Mercury

Authors: Shiliang Wu, Huanxin Zhang

Abstract:

Mercury has been well-known for its negative effects on wildlife, public health as well as the ecosystem. Once emitted into atmosphere, mercury can be transformed into different forms or enter the ecosystem through dry deposition or wet deposition. Some fraction of the mercury will be reemitted back into the atmosphere and be subject to the same cycle. In addition, the relatively long lifetime of elemental mercury in the atmosphere enables it to be transported long distances from source regions to receptor regions. Global change such as climate change and land use/land cover change impose significant challenges for mercury pollution control besides the efforts to regulate mercury anthropogenic emissions. In this study, we use a global chemical transport model (GEOS-Chem) to examine the potential impacts from changes in climate and land use/land cover on the global budget of mercury as well as its atmospheric transport, chemical transformation, and deposition. We carry out a suite of sensitivity model simulations to separate the impacts on atmospheric mercury associated with changes in climate and land use/land cover. Both climate change and land use/land cover change are found to have significant impacts on global mercury budget but through different pathways. Land use/land cover change primarily increase mercury dry deposition in northern mid-latitudes over continental regions and central Africa. Climate change enhances the mobilization of mercury from soil and ocean reservoir to the atmosphere. Also, dry deposition is enhanced over most continental areas while a change in future precipitation dominates the change in mercury wet deposition. We find that 2000-2050 climate change could increase the global atmospheric burden of mercury by 5% and mercury deposition by up to 40% in some regions. Changes in land use and land cover also increase mercury deposition over some continental regions, by up to 40%. The change in the lifetime of atmospheric mercury has important implications for long-range transport of mercury. Our case study shows that changes in climate and land use and cover could significantly affect the source-receptor relationships for mercury.

Keywords: mercury, toxic pollutant, atmospheric transport, deposition, climate change

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2442 Depression among University Students an Epidemiological Study on a Sample of University Students

Authors: Laid Fekih

Abstract:

Background: Depression affects people in all communities across the world and in all aspects of their lives. Its spread varies from one country to another, can happen at any age and get rid of it is not easy. There is no clear policy in Algeria's higher education institutions to detect and treat these disorders or pay particular attention to those at risk. Identifying the prevalence of depression among Algerian students, its correlation with different variables, and studying gender differences in the light of a range of variables is necessary to develop an appropriate plan to raise the level of hope and love of life among students. Method: Random samples of 1500 University of Tlemcen students (967 girls and 533 boys), aged 19 to 24 years completed a self-administered questionnaire that included Beck's Depression Inventory ®-II (BDI®-II), (School Health Promotion: The Mood part), Other questions included in this survey focused on demographic characteristics including gender, age and year of study, academic performance (Annual Average Score (0-20) AAS), were examined. Results: The rate of depression (moderate, severe and extreme) varied from 03% to 13% among university students in Tlemcen University. There was no difference in the rates of depression in male and female students, which means that male and female students do have similar rates of depression. The rate of depression in the first-year of the study shows a higher score relative to students of other years. Depression has a negative relationship with academic performance, which means that depressed students have many difficulties in academic tasks at university. Conclusion: Depression among university students is an important center of interest in the world, not only because of the ease with which they can be followed, or the difficulties encountered during their studies and their technical courses but for the link between the level of depression and the quality of care of mental health services, especially if many students with mood and emotional problems don't meet the criteria for psychotherapy.

Keywords: depression, epidemiology, university students, academic performance

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2441 The Complex Relationship Between IQ and Attention Deficit Hyperactivity Disorder Symptoms: Insights From Behaviors, Cognition, and Brain in 5,138 Children With Attention Deficit Hyperactivity Disorder

Authors: Ningning Liu, Gaoding Jia, Yinshan Wang, Haimei Li, Xinian Zuo, Yufeng Wang, Lu Liu, Qiujin Qian

Abstract:

Background: There has been speculation that a high IQ may not necessarily provide protection against attention deficit hyperactivity disorder (ADHD), and there may be a U-shaped correlation between IQ and ADHD symptoms. However, this speculation has not been validated in the ADHD population in any study so far. Method: We conducted a study with 5,138 children who have been professionally diagnosed with ADHD and have a wide range of IQ levels. General Linear Models were used to determine the optimal model between IQ and ADHD core symptoms with sex and age as covariates. The ADHD symptoms we looked at included the total scores (TO), inattention (IA) and hyperactivity/impulsivity (HI). Wechsler Intelligence scale were used to assess IQ [Full-Scale IQ (FSIQ), Verbal IQ (VIQ), and Performance IQ (PIQ)]. Furthermore, we examined the correlation between IQ and the execution function [Behavior Rating Inventory of Executive Function (BRIEF)], as well as between IQ and brain surface area, to determine if the associations between IQ and ADHD symptoms are reflected in executive functions and brain structure. Results: Consistent with previous research, the results indicated that FSIQ and VIQ both showed a linear negative correlation with the TO and IA scores of ADHD. However, PIQ showed an inverted U-shaped relationship with the TO and HI scores of ADHD, with 103 as the peak point. These findings were also partially reflected in the relationship between IQ and executive functions, as well as IQ and brain surface area. Conclusion: To sum up, the relationship between IQ and ADHD symptoms is not straightforward. Our study confirms long-standing academic hypotheses and finds that PIQ exhibits an inverted U-shaped relationship with ADHD symptoms. This study enhances our understanding of symptoms and behaviors of ADHD with varying IQ characteristics and provides some evidence for targeted clinical intervention.

Keywords: ADHD, IQ, execution function, brain imaging

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2440 Early Marriage and Women's Empowerment: The Case of Chil-bride in East Hararghe Zone of Oromia National Regional State, Ethiopia

Authors: Emad Mohammed Sani

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Women encounter exclusion and discrimination in varying degrees, particularly those who marry as minors. The detrimental custom of getting married young is still prevalent worldwide and affects millions of people. It has been less common over time, although it is still widespread in underdeveloped nations. Oromia Regional State is the region in Ethiopia with the highest proportion of child brides. This study aimed at evaluating the effects of early marriage on its survivors’ life conditions – specifically, empowerment and household decision-making – in Eastern Hararghe Zone of Oromia Region. This study employed community-based cross-sectional study design. It adopted mixed method approach – survey, in-depth interview and focus group discussion (FGD) – to collect, analyses and interpret data on early marriage and its effects on household decision-making processes. Narratives and analytical descriptions were integrated to substantiate and/or explain observed quantitative results, or generate contextual themes. According to this study, married women who were married at or after the age of eighteen participated more in household decision-making than child brides. Child brides were more likely to be victims of violence and other types of spousal abuse in their marriages. These changes are mostly caused by an individual's age at first marriage. Delaying marriage had a large positive impact on women's empowerment at the household level, and age at first marriage had a considerable negative impact. In order to advance women's welfare and emancipation, we advise more research to concentrate on the relationship between the home and the social-structural forms that appear at the individual and communal levels.

Keywords: child-bride, early marriage, women, ethiopia

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2439 Comparison of Various Landfill Ground Improvement Techniques for Redevelopment of Closed Landfills to Cater Transport Infrastructure

Authors: Michael D. Vinod, Hadi Khabbaz

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Construction of infrastructure above or adjacent to landfills is becoming more common to capitalize on the limited space available within urban areas. However, development above landfills is a challenging task due to large voids, the presence of organic matter, heterogeneous nature of waste and ambiguity surrounding landfill settlement prediction. Prior to construction of infrastructure above landfills, ground improvement techniques are being employed to improve the geotechnical properties of landfill material. Although the ground improvement techniques have little impact on long term biodegradation and creep related landfill settlement, they have shown some notable short term success with a variety of techniques, including methods for verifying the level of effectiveness of ground improvement techniques. This paper provides geotechnical and landfill engineers a guideline for selection of landfill ground improvement techniques and their suitability to project-specific sites. Ground improvement methods assessed and compared in this paper include concrete injected columns (CIC), dynamic compaction, rapid impact compaction (RIC), preloading, high energy impact compaction (HEIC), vibro compaction, vibro replacement, chemical stabilization and the inclusion of geosynthetics such as geocells. For each ground improvement technique a summary of the existing theory, benefits, limitations, suitable modern ground improvement monitoring methods, the applicability of ground improvement techniques for landfills and supporting case studies are provided. The authors highlight the importance of implementing cost-effective monitoring techniques to allow observation and necessary remediation of the subsidence effects associated with long term landfill settlement. These ground improvement techniques are primarily for the purpose of construction above closed landfills to cater for transport infrastructure loading.

Keywords: closed landfills, ground improvement, monitoring, settlement, transport infrastructure

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2438 Bioelectronic System for Continuous Monitoring of Cardiac Activity of Benthic Invertebrates for the Assessment of a Surface Water Quality

Authors: Sergey Kholodkevich, Tatiana Kuznetsova

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The objective assessment of ecological state of water ecosystems is impossible without the use of biological methods of the environmental monitoring capable in the integrated look to reveal negative for biota changes of quality of water as habitats. Considerable interest for the development of such methods of environmental quality control represents biomarker approach. Measuring systems, by means of which register cardiac activity characteristics, received the name of bioelectronic. Bioelectronic systems are information and measuring systems in which animals (namely, benthic invertebrates) are directly included in structure of primary converters, being an integral part of electronic system of registration of these or those physiological or behavioural biomarkers. As physiological biomarkers various characteristics of cardiac activity of selected invertebrates have been used in bioelectronic system.lChanges in cardiac activity are considered as integrative measures of the physiological condition of organisms, which reflect the state of the environment of their dwelling. Greatest successes in the development of tools of biological methods and technologies of an assessment of surface water quality in real time. Essential advantage of bioindication of water quality by such tool is a possibility of an integrated assessment of biological effects of pollution on biota and also the expressness of such method and used approaches. In the report the practical experience of authors in biomonitoring and bioindication of an ecological condition of sea, brackish- and freshwater areas is discussed. Authors note that the method of non-invasive cardiac activity monitoring of selected invertebrates can be used not only for the advancement of biomonitoring, but also is useful in decision of general problems of comparative physiology of the invertebrates.

Keywords: benthic invertebrates, physiological state, heart rate monitoring, water quality assessment

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2437 Impact of Tryptic Limited Hydrolysis on Bambara Protein-Gum Arabic Soluble Complexes Formation

Authors: Abiola A. Ojesanmi, Eric O. Amonsou

Abstract:

The formation of soluble complexes is usually within a narrow pH range characterized by weak interactions. Moreover, the rigid conformation of globular proteins restricts the number of charged groups capable of interacting with polysaccharides, thereby limiting food applications. Hence, this study investigated the impact of tryptic-limited hydrolysis on the formation of Bambara protein-gum arabic soluble complexes formation. The electrostatic interactions were monitored through turbidimetry analysis. The Bambara protein hydrolysates at a specified degree of hydrolysis, and DHs (2, 5, and 7.5) were characterized using size exclusion chromatography, zeta potential, surface hydrophobicity, and intrinsic fluorescence. The stability of the complexes was investigated using differential scanning calorimetry and rheometry. The limited tryptic hydrolysis significantly widened the pH range of the formation of soluble complexes, with DH 5 having a wider range (pH 7.0 - 4.3) compared to DH 2 and DH 7.5, while there was no notable difference in the optimum complexation pH of the insoluble complexes. Larger peptides (140, 118 kDa) were detected in DH 2 relative to 144, 70, and 61 kDa in DH 5, which were larger than 140, 118, 48, and 32 kDa in DH 7. 5. An increase in net negative charge (- 30 Mv for DH 7.5) and a slight shift in the net neutrality (from pH 4.9 to 4.3) of the hydrolysates were observed which consequently impacted the electrostatic interaction with gum arabic. There was exposure of the hydrophobic amino acids up to 4-fold in comparison with the isolate and a red shift in maximum fluorescence wavelength in DH dependent manner following the hydrolysis. The denaturation temperature of the soluble complex from the hydrolysates shifted to higher values, having DH 5 with the maximum temperature (94.24 °C). A highly interconnected gel-like soluble complex network was formed having DH 5 with a better structure relative to DH 2 and 7.5. The study showed the use of limited tryptic hydrolysis at DH 5 as an effective approach to modify Bambara protein and provided a more stable and wider pH range of formation for soluble complex, thereby enhancing the food application.

Keywords: Bambara groundnut, gum arabic, interaction, soluble complex

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2436 The Construction and Representation of Muslim Identity in Bollywood Commercial Films

Authors: Abonti Mehtaz

Abstract:

The utmost controversial issue that Bollywood movies deal with is religious conflicts and the representation of Islam and or Muslims. The main objective of this paper is to examine that, how Muslim identity is constructed in Bollywood commercial films through the representation of Muslims and/or Islam. Two hypotheses are developed for this study, i.e., (1) Bollywood commercial films often portray the stereotypical image of Muslims. (2) The portrayal of Muslims and Islam in Bollywood commercial films is often negative. (3) Bollywood commercial films frequently construct a wrong and fake identity of Muslims through an inappropriate representation of Muslims and Islam. This study employs qualitative research techniques. To examine the hypotheses of this paper, 10 Bollywood commercial films produced in between 2000-2018 are selected purposively such as Fiza (2000), Gadar: Ek Prem Katha (2001), Company (2002), Aamir (2008), Kurbaan (2009), Anwar (2010), My name is Khan (2010), Raanjhanaa (2013), Omerta (2017) and Pari (2018). By conducting textual analyses of the above mentioned Bollywood commercial films, this paper focuses on different approaches of Muslim identity and their construction as well as representation in Bollywood commercial films in the light of scholarly work in film and cultural studies. Though 10 Bollywood commercial films are selected for contextual analysis, other Bollywood films by other directors are also mentioned in order to establish the hypotheses of this study. Framing theory is used to analyze the media contents. Findings of this study show that all hypotheses are accepted. Bollywood commercial films continually represent Islam and Muslims in incorrect ways and by doing so Bollywood commercial films construct a fallacious Muslim identity. Though the sample size of contents can be considered as a limitation of this study, the findings of the study reveal that how Bollywood commercial film is setting agenda to manipulate the image of Muslims and Islam not only in India but all over the world.

Keywords: Bollywood commercial films, Muslim identity, misrepresentation, representation, stereotypical

Procedia PDF Downloads 194
2435 Governance Challenges of Consolidated Destinations. The Case of Barcelona

Authors: Montserrat Crespi-Vallbona; Oscar Mascarilla-Miró

Abstract:

Mature destinations have different challenges trying to attract tourism and please its citizens. Hence, they have to maintain their touristic interest to standard demand and also not to undeceive those tourists with more advanced experiences. Second, they have to be concerned for the daily life of citizens and avoid the negative effects of touristification. This balance is quite delicate and often has to do with the sensitivity and commitment of the party in the local government. However, what is a general consensus is the need for destinations to differentiate from the homogeneous rest of regions and create new content, consumable resources or marketing events to guarantee their positioning. In this sense, the main responsibility of destinations is to satisfy users, tourists and citizens. Hence, its aim has to do with holistic experiences, which collect these wide approaches. Specifically, this research aims to analyze the volume and growth of tourist houses in the central touristic neighborhoods of Barcelona (this is Ciutat Vella) as the starting point to identify the behavior of tourists regarding their interests in searching for local heritage attractiveness and community atmosphere. Then, different cases are analyzed in order to show how Barcelona struggles to keep its attractive brand for the visitors, as well as for its inhabitants. Methodologically, secondary data used in this research comes from official registered tourist houses (Catalunya Government), Open Data (Barcelona municipality), the Airbnb tourist platform, from the Incasol Data and Municipal Register of Inhabitants. Primary data are collected through in-depth interviews with neighbors, social movement managers and political representatives from Turisme de Barcelona (local DMO, Destination Management Organization). Results show what the opportunities and priorities are for key actors to design policies to find a balance between all different interests.

Keywords: touristification, tourist houses, governance, tourism demand, airbnbfication

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2434 Effect of Phaseolus vulgaris Inoculation on P. vulgaris and Zea mays Growth and Yield Cultivated in Intercropping

Authors: Nour Elhouda Abed, Bedj Mimi, Wahid Slimani, Mourad Atif, Abdelhakim Ouzzane, Hocine Irekti, Abdelkader Bekki

Abstract:

The most frequent system of cereal production in Algeria is fallow-wheat. This is an extensive system that meets only the half needs some cereals and fodder demand. Resorption of fallow has become a strategic necessity to ensure food security in response to the instability of supply and the persistence of higher food prices on the world market. Despite several attempts to replace the fallow by crop cultures, choosing the best crop remains. Today, the agronomic and economic interests of legumes are demonstrated. However, their crop culture remains marginalized because of the weakness and instability of their performance. In the context of improving legumes and cereals crops as well as fallow resorption, we undertook to test, in the field, the effect of rhizobial inoculation of Phaseolus vulgaris in association with Zea Mays. We firstly studied the genetic diversity of rhizobial strains that nodulate P.vulgaris isolated from fifteen (15) different regions. ARDRA had shown 18 different genetic profiles. Symbiotic characterization highlighted a strain that highly significantly improved the fresh and dry weight of the host plant, in comparison to the negative control (un-inoculated) and the positive control (inoculated with the reference strain CIAT 899). In the field, the selected strain increased significantly the growth and yield of P.vulgaris and Zea Mays comparing to the non-inoculated control. However, the mix inoculation (selected strain+ Ciat 899) had not given the best parameters showing, thus, no synergy between the strains. These results indicate the replacing fallow by a crop legume in intercropping with cereals crops.

Keywords: fallow, intercropping, inoculation, legumes-cereals

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2433 Internet Impulse Buying: A Study Based on Stimulus-Organism-Response Theory

Authors: Pui-Lai To, Yi-Jing Tsai

Abstract:

As the advance of e-commerce technologies, the consumers buying behavior have changed. The focus on consumer buying behavior has already shifted from physical space to the cyberspace, which impulse buying is a major issue of concern. This study examines the stimulus effect of web environment on the consumer's emotional states, and in turn, affecting the urge of impulse buying based on a stimulus-organism-response (S-O-R) theory. Website ambiance and website service quality are the two stimulus variables. The study also explores the effects and the moderator effects of contextual variables and individual characteristic variables on the web environment, the emotional states and the urge of impulse buying. A total of 328 valid questionnaires were collected. Structural equation modeling was used to test the research hypothesis. This study found that both website ambiance and website service quality have a positive effect on consumer emotion, which in turn positively affect the urge of impulse buying. Consumer’s trait of impulse buying has a positive effect on the urge of impulse buying. Consumer’s hedonic motivation has a positive effect on both emotion state and the urge of impulse buying. On the other hand, the study found that money available for the consumer would positively affect consumer's emotion state and time available for the consumer would negatively affect the relationship between website service quality and consumer emotion. The result of this study validates Internet impulse buying behavior based on the S-O-R theory. This study also suggests that having a good website atmosphere and service quality is important to influencing consumers’ emotion and increasing the likelihood of consumer purchasing. The study could serve as a basis for the future research regarding online consumer behavior.

Keywords: emotion state, impulse buying, stimulus-organism-response, the urge of impulse buying

Procedia PDF Downloads 220
2432 Development of an Interactive and Robust Image Analysis and Diagnostic Tool in R for Early Detection of Cervical Cancer

Authors: Kumar Dron Shrivastav, Ankan Mukherjee Das, Arti Taneja, Harpreet Singh, Priya Ranjan, Rajiv Janardhanan

Abstract:

Cervical cancer is one of the most common cancer among women worldwide which can be cured if detected early. Manual pathology which is typically utilized at present has many limitations. The current gold standard for cervical cancer diagnosis is exhaustive and time-consuming because it relies heavily on the subjective knowledge of the oncopathologists which leads to mis-diagnosis and missed diagnosis resulting false negative and false positive. To reduce time and complexities associated with early diagnosis, we require an interactive diagnostic tool for early detection particularly in developing countries where cervical cancer incidence and related mortality is high. Incorporation of digital pathology in place of manual pathology for cervical cancer screening and diagnosis can increase the precision and strongly reduce the chances of error in a time-specific manner. Thus, we propose a robust and interactive cervical cancer image analysis and diagnostic tool, which can categorically process both histopatholgical and cytopathological images to identify abnormal cells in the least amount of time and settings with minimum resources. Furthermore, incorporation of a set of specific parameters that are typically referred to for identification of abnormal cells with the help of open source software -’R’ is one of the major highlights of the tool. The software has the ability to automatically identify and quantify the morphological features, color intensity, sensitivity and other parameters digitally to differentiate abnormal from normal cells, which may improve and accelerate screening and early diagnosis, ultimately leading to timely treatment of cervical cancer.

Keywords: cervical cancer, early detection, digital Pathology, screening

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2431 Influence of Gold Nanoparticles on NiAlZr Type Layered Double Hydroxide for the Catalytic Transfer Oxidation of Biomass Derived Aldehydes

Authors: Nihel Dib, Redouane Bachir, Ghezlane Berrahou, Chaima Zoulikha Tabet Zatla, Sumeya Bedrane, Ginessa Blanco Montilla, Jose Juan Calvino Gamez

Abstract:

In recent decades, the world’s population has rapidly increased annually, resulting in the consumption of huge amounts of conventional non-renewable petroleum-based resources at an alarming rate. The scarcity of such resources will shut down the corresponding industries and consequently have negative effects on the well-being of humanity. Accordingly, to combat the forthcoming crises and to serve the ever-growing demands, seeking potentially sustainable resources such as geothermal, wind, solar, and biomass has become an active field of study. Currently, lignocellulosic biomass, one of the world’s most plentiful resources, is acknowledged as a cost-effective material that has drawn great interest from many researchers since it has substantial energy potential as well as containing useful C5 and C6 sugars. These C5 and C6 sugars are the key reactants for the production of the valuable 16-platform chemicals such as 5-hydroxymethyl furfural, furfural, levulinic acid, succinic acid, and fumaric acid, all of which are crucial intermediates for synthesizing high-value bio-based chemicals and polymers. Succinic acid (SA) has been predicted to make a significant contribution to the global bio-based economy soon since it serves as a C4 building block that is used in a wide spectrum of industries, including biopolymers, solvents, and pharmaceuticals. In the present work, we modify the HDL MgAl with Zr to try to create acid sites on the supports and deposit gold by deposition precipitation with urea with a low gold content (0.25%). The catalyst was used to produce succinic acid by selective oxidation of furfuraldehyde with hydrogen peroxide under mild reaction conditions.

Keywords: hydrotalcite, catalysis, gold, biomass, furfural, oxidation

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2430 Conservation Importance of Independent Smallholdings in Safeguarding Biodiversity in Oil Palm Plantations

Authors: Arzyana Sunkar, Yanto Santosa

Abstract:

The expansions of independent smallholdings in Indonesia are feared to increase the negative ecological impacts of oil palm plantation on biodiversity. Hence, research is required to identify the conservation importance of independent smallholder oil palm plantations on biodiversity. This paper discussed the role of independent smallholdings in the conservation of biodiversity in oil palm plantations and to compare it with High Conservation Value Forest as a conservation standard of RSPO. The research was conducted from March to April 2016. Data on biodiversity were collected on 16 plantations and 8 private oil palm plantations in the Districts of Kampar, Pelalawan, Kuantan, Singingi and Siak of Riau Province, Indonesia. In addition, data on community environmental perceptions of both smallholder plantation and High Conservation Value (HCV) Forest were also collected. Species that were observed were birds and earthworms. Data on birds were collected using transect method, while identification of earthworm was determine by taking some soil samples and counting the number of individual earthworm found for each worm species. The research used direct interview with oil palm owners and community members, as well as direct observation to examine the environmental conditions of each plantation. In general, field observation and measurement have found that birds species richness was higher in the forested HCV Forest. Nevertheless, if compared to non-forested HCV, bird’s species richness was higher in the independent smallholdings. On the other hand, different results were observed for earthworm, where the density was higher in the independent smallholdings than in the HCV. It can be concluded from this research that managing independent smallholder oil palm plantations and forested HCV forest could enhance biodiversity conservation. The results of this study justified the importance of retaining forested area to safeguard biodiversity in oil palm plantation.

Keywords: biodiversity conservation, high conservation value forest, independent smallholdings, oil palm plantations

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2429 An Analysis of Transition in Building Form from Abolition of Diagonal Plane Control by Street Width: Focusing on Site Plan and Urban Block

Authors: Joohyun Park, Jin Baek

Abstract:

The purpose of this study is to Analyze the role and effect arise from Diagonal Plane Control by Street Width (DPCSW) in Architecture in Seoul, and to predict the aspect of transition about the relationship among buildings and Urban morphology After the abolition. To find the tendency of building shape regulation, This study review Building Acts concerned with form making (the building to land Ratio, building designated line, wall designated line, building height limit (DPCSW) and etc.) and simulate the shape of urban blocks made by Acts in drawings. The review results show DPCSW is not only limitation about height, but also making the building setback from road and make the Road broader. And it makes the typical shape of the urban block that buildings are moving away from surrounding road After the Abolition of DPCSW; it is expected by the legislature that domestic real estate’s market would be promoted by increased total floor areas in each building. Some substitution from the legislature is announced, but it just deals with Building Maximum unit by Block unit except the regulation about arrangement in urban Figure and Ground. In conclusion, refrain from the uncontrolled development of city, It is important to make regulation about not only height factors but limitation line in land. Furthermore, through revising District Unit Plan, It is positively necessary to reset the relationship between buildings for the making the city space better.

Keywords: diagonal plane control by street width, building maximum height, district unit plan, building acts, urban block type, morphology, building shape

Procedia PDF Downloads 295
2428 Response of Different Mulch Materials on Cowpea (Vigna unguiculata ) Growth and Yield in Tolon District

Authors: Adu Micheal Kwaku, Lamptey Shirley

Abstract:

Cowpea (Vigna unguiculata (L.) Walpis) is a major food grain legume in Ghana and plays a significant role in consumer diets. Drought in rain-fed crop production is known to cause substantial crop yield reduction due to their negative impacts on plant growth, physiology, and reproduction. There are various ways of reducing the effect of drought or addressing the problem of drought stress, including irrigation, breeding, and mulching. Among these three ways of reducing the effect of drought stress, the cheapest and quickest method is mulching. The broad objective of this project is to determine the influence of mulching on the performance of cowpea. The experiment was conducted at Planting for future garden located at Nyankpala Campus of the University for Development Studies (UDS), comprising five treatments (black plastic, rice hull, groundnut hull, dry grass mulch, and control). The treatments were evaluated in a Randomized Complete Block Design (RCBD) with three replications. The result shows that black plastic mulch increased soil moisture by 1, 8, 15, and 24% compared to rice hull, groundnut hull, dry grass, and control, respectively. Increased soil moisture translated into black plastic mulch increasing grain yield by 8, 25, 39, and 46% compared to groundnut hull, rice hull, dry grass and control, respectively. However, black plastic mulch increased the cost of production, resulting in decreased net returns compared to the other treatment. This study recommends the use of rice and groundnut hull as mulching material to improve soil moisture, grain yield, and profit of smallholder cowpea farmers and also because they are almost free and available.

Keywords: mulch, plastic mulch, cowpea, growth response

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2427 Is Audit Quality Implied by Accruals Quality Associated with Audit Fees and Auditor Tenure? Evidence from China

Authors: Hassan Y. Kikhia, Jin P. Zhang, Khaldoon G. Albiatr

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The Enron and Arthur Andersen scandal has raised concerns internationally about auditor independence and audit quality. Furthermore, the debate continues about the relationship between audit fees, auditor tenure and audit quality in spite of extensive empirical evidence examining audit failures and earnings management. Therefore, the purpose of current research is to determine the effect of audit fee and audit tenure both partially and simultaneously on the audit quality. Using a sample of Chinese firms, an environment where we believe it provides us with an opportunity to test whether the development of market and legal institutions affects the impact of audit fees and auditor tenure on audit quality. We employ the standard deviation of residuals from regressions relating current accruals to cash flows as proxy for audit quality. The paper documents statistically significant negative association between audit fees and audit quality. These findings are consistent with economic bonding being a determinant of auditor behavior rather than auditor reputational concerns. Further, the current paper shows a positive association between auditor tenure and audit quality in the earlier years of audit tenure. These results support the proposition that when the Learning Effect dominates the Bonding Effect in the earlier years of tenure, then audit quality is likely to be higher. Taken audit fees and audit tenure together, the results suggest that there is positive association between audit fees and audit quality in the earlier years of auditor tenure. Interestingly, the findings of our study have important implications for auditors, policymakers, multinational firms, and users of financial reports. As the rapid growth of China's economy gains global recognition, the Chinese stock market is capturing the attention of international investors. To a lesser extent, our paper also differs from the prior studies in methodology and findings in the investigation of audit quality.

Keywords: audit quality, accruals quality, audit fees, auditor tenure

Procedia PDF Downloads 268
2426 Modelling Insider Attacks in Public Cloud

Authors: Roman Kulikov, Svetlana Kolesnikova

Abstract:

Last decade Cloud Computing technologies have been rapidly becoming ubiquitous. Each year more and more organizations, corporations, internet services and social networks trust their business sensitive information to Public Cloud. The data storage in Public Cloud is protected by security mechanisms such as firewalls, cryptography algorithms, backups, etc.. In this way, however, only outsider attacks can be prevented, whereas virtualization tools can be easily compromised by insider. The protection of Public Cloud’s critical elements from internal intruder remains extremely challenging. A hypervisor, also called a virtual machine manager, is a program that allows multiple operating systems (OS) to share a single hardware processor in Cloud Computing. One of the hypervisor's functions is to enforce access control policies. Furthermore, it prevents guest OS from disrupting each other and from accessing each other's memory or disk space. Hypervisor is the one of the most critical and vulnerable elements in Cloud Computing infrastructure. Nevertheless, it has been poorly protected from being compromised by insider. By exploiting certain vulnerabilities, privilege escalation can be easily achieved in insider attacks on hypervisor. In this way, an internal intruder, who has compromised one process, is able to gain control of the entire virtual machine. Thereafter, the consequences of insider attacks in Public Cloud might be more catastrophic and significant to virtual tools and sensitive data than of outsider attacks. So far, almost no preventive security countermeasures have been developed. There has been little attention paid for developing models to assist risks mitigation strategies. In this paper formal model of insider attacks on hypervisor is designed. Our analysis identifies critical hypervisor`s vulnerabilities that can be easily compromised by internal intruder. Consequently, possible conditions for successful attacks implementation are uncovered. Hence, development of preventive security countermeasures can be improved on the basis of the proposed model.

Keywords: insider attack, public cloud, cloud computing, hypervisor

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2425 Protective Coating Layers via Phosphazene Compounds for Stabilizing Silicon Anode Materials

Authors: Adjmal Ghaur, Christoph Peschel, Iris Dienwiebel, Lukas Haneke, Leilei Du , Laurin Profanter, Tobias Placke, Martin Winter

Abstract:

In recent years, lithium-ion batteries (LIBs)are widely used in electric vehicles (EVs) and mobile energy storage devices (ESDs), which has led to higher requirements for energy density. To fulfill these requirements, tremendous attention has been paid to design advanced LIBs with various siliconactive materials as alternative negative electrodes to replace graphite (372 mAh g⁻¹)due to their high theoretical gravimetric capacity (4200mAh g⁻¹). However, silicon as potential anode material suffers from huge volume changes during charging and discharging and has poor electronicconductivity which negatively impacts the long-term performance and preventshigh silicon contents from practical application. Additionally, an unstable crystalline silicon structure tends to pulverization during the (de)lithiation process. To compensate for the volume changes, alleviate pulverization, and maintain high electronicconductivity, silicon-doped graphite composites with protecting coating layers are a promising approach. In this context, phosphazene compounds are investigated concerning their silicon protecting properties in silicon-doped graphite composites. In detail, electrochemical performance measurements in pouch full-cells(NCM523||SiOx/C), supressing gas formation properties, and post-mortem analyzes were carried out to characterize phosphazene compounds as additive materials. The introduction of the dual-additive approach in state-of-the-art electrolytes leads to synergistic effects between FEC and phosphazene compounds which accelerate the durability of silicon particles and results in enhanced electrochemical performance.

Keywords: silicon, phosphazene, solid electrolyte interphase, electrolyte, gasmeasurements

Procedia PDF Downloads 147