Search results for: particle size distribution (PSD)
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 10567

Search results for: particle size distribution (PSD)

997 Assessment of the Landscaped Biodiversity in the National Park of Tlemcen (Algeria) Using Per-Object Analysis of Landsat Imagery

Authors: Bencherif Kada

Abstract:

In the forest management practice, landscape and Mediterranean forest are never posed as linked objects. But sustainable forestry requires the valorization of the forest landscape, and this aim involves assessing the spatial distribution of biodiversity by mapping forest landscaped units and subunits and by monitoring the environmental trends. This contribution aims to highlight, through object-oriented classifications, the landscaped biodiversity of the National Park of Tlemcen (Algeria). The methodology used is based on ground data and on the basic processing units of object-oriented classification, that are segments, so-called image-objects, representing a relatively homogenous units on the ground. The classification of Landsat Enhanced Thematic Mapper plus (ETM+) imagery is performed on image objects and not on pixels. Advantages of object-oriented classification are to make full use of meaningful statistic and texture calculation, uncorrelated shape information (e.g., length-to-width ratio, direction, and area of an object, etc.), and topological features (neighbor, super-object, etc.), and the close relation between real-world objects and image objects. The results show that per object classification using the k-nearest neighbor’s method is more efficient than per pixel one. It permits to simplify of the content of the image while preserving spectrally and spatially homogeneous types of land covers such as Aleppo pine stands, cork oak groves, mixed groves of cork oak, holm oak, and zen oak, mixed groves of holm oak and thuja, water plan, dense and open shrub-lands of oaks, vegetable crops or orchard, herbaceous plants, and bare soils. Texture attributes seem to provide no useful information, while spatial attributes of shape and compactness seem to be performant for all the dominant features, such as pure stands of Aleppo pine and/or cork oak and bare soils. Landscaped sub-units are individualized while conserving the spatial information. Continuously dominant dense stands over a large area were formed into a single class, such as dense, fragmented stands with clear stands. Low shrublands formations and high wooded shrublands are well individualized but with some confusion with enclaves for the former. Overall, a visual evaluation of the classification shows that the classification reflects the actual spatial state of the study area at the landscape level.

Keywords: forest, oaks, remote sensing, diversity, shrublands

Procedia PDF Downloads 99
996 Organizational Stress in Women Executives

Authors: Poornima Gupta, Sadaf Siraj

Abstract:

The study examined the organizational causes of organizational stress in women executives and entrepreneurs in India. This was done so that mediation strategies could be developed to combat the organizational stress experienced by them, in order to retain the female employees as well as attract quality talent. The data for this research was collected through the self- administered survey, from the women executives across various industries working at different levels in management. The research design of the study was descriptive and cross-sectional. It was carried out through a self-administered questionnaire filled in by the women executives and entrepreneurs in the NCR region. Multistage sampling involving stratified random sampling was employed. A total of 1000 questionnaires were distributed out of which 450 were returned and after cleaning the data 404 were fit to be considered for analyses. The overall findings of the study suggested that there were various job-related factors that induce stress. Fourteen factors were identified which were a major cause of stress among the working women by applying Factor analysis. The study also assessed the demographic factors which influence the stress in women executives across various industries. The findings show that the women, no doubt, were stressed by organizational factors. The mean stress score was 153 (out of a possible score of 196) indicating high stress. There appeared to be an inverse relationship between the marital status, age, education, work experience, and stress. Married women were less stressed compared to single women employees. Similarly, female employees 29 years or younger experienced more stress at work. Women having education up to 12th standard or less were more stressed compared to graduates and post graduates. Women who had spent more than two years in the same organization perceived more stress compared to their counterparts. Family size and income, interestingly, had no significant impact on stress. The study also established that the level of stress experienced by women across industries differs considerably. Banking sector emerged as the industry where the women experienced the most stress followed by Entrepreneurs, Medical, BPO, Advertising, Government, Academics, and Manufacturing, in that order. The results contribute to the better understanding of the personal and economic factors surrounding job stress and working women. It concludes that the organizations need to be sensitive to the women’s needs. Organizations are traditionally designed around men with the rules made by the men for the men. Involvement of women in top positions, decision making, would make them feel more useful and less stressed. The invisible glass ceiling causes more stress than realized among women. Less distinction between the men and women colleagues in terms of giving responsibilities, involvement in decision making, framing policies, etc. would go a long way to reduce stress in women.

Keywords: women, stress, gender in management, women in management

Procedia PDF Downloads 238
995 Increased Efficiency during Oxygen Carrier Aided Combustion of Municipal Solid Waste in an Industrial Scaled Circulating Fluidized Bed-Boiler

Authors: Angelica Corcoran, Fredrik Lind, Pavleta Knutsson, Henrik Thunman

Abstract:

Solid waste volumes are at current predominately deposited on landfill. Furthermore, the impending climate change requires new solutions for a sustainable future energy mix. Currently, solid waste is globally utilized to small extent as fuel during combustion for heat and power production. Due to its variable composition and size, solid waste is considered difficult to combust and requires a technology with high fuel flexibility. One of the commercial technologies used for combustion of such difficult fuels is circulating fluidized beds (CFB). In a CFB boiler, fine particles of a solid material are used as 'bed material', which is accelerated by the incoming combustion air that causes the bed material to fluidize. The chosen bed material has conventionally been silica sand with the main purpose of being a heat carrier, as it transfers heat released by the combustion to the heat-transfer surfaces. However, the release of volatile compounds occurs rapidly in comparison with the lateral mixing in the combustion chamber. To ensure complete combustion a surplus of air is introduced, which decreases the total efficiency of the boiler. In recent years, the concept of partly or entirely replacing the silica sand with an oxygen carrier as bed material has been developed. By introducing an oxygen carrier to the combustion chamber, combustion can be spread out both temporally and spatially in the boiler. Specifically, the oxygen carrier can take up oxygen from the combustion air where it is in abundance and release it to combustible gases where oxygen is in deficit. The concept is referred to as oxygen carrier aided combustion (OCAC) where the natural ore ilmenite (FeTiO3) has been the oxygen carrier used. The authors have validated the oxygen buffering ability of ilmenite during combustion of biomass in Chalmers 12-MWth CFB boiler in previous publications. Furthermore, the concept has been demonstrated on full industrial scale during combustion of municipal solid waste (MSW) in E.ON’s 75 MWth CFB boiler. The experimental campaigns have showed increased mass transfer of oxygen inside the boiler when combustion both biomass and MSW. As a result, a higher degree of burnout is achieved inside the combustion chamber and the plant can be operated at a lower surplus of air. Moreover, the buffer of oxygen provided by the oxygen carrier makes the system less sensitive to disruptions in operation. In conclusion, combusting difficult fuels with OCAC results in higher operation stability and an increase in boiler efficiency.

Keywords: OCAC, ilmenite, combustion, CFB

Procedia PDF Downloads 224
994 The Inverse Problem in Energy Beam Processes Using Discrete Adjoint Optimization

Authors: Aitor Bilbao, Dragos Axinte, John Billingham

Abstract:

The inverse problem in Energy Beam (EB) Processes consists of defining the control parameters, in particular the 2D beam path (position and orientation of the beam as a function of time), to arrive at a prescribed solution (freeform surface). This inverse problem is well understood for conventional machining, because the cutting tool geometry is well defined and the material removal is a time independent process. In contrast, EB machining is achieved through the local interaction of a beam of particular characteristics (e.g. energy distribution), which leads to a surface-dependent removal rate. Furthermore, EB machining is a time-dependent process in which not only the beam varies with the dwell time, but any acceleration/deceleration of the machine/beam delivery system, when performing raster paths will influence the actual geometry of the surface to be generated. Two different EB processes, Abrasive Water Machining (AWJM) and Pulsed Laser Ablation (PLA), are studied. Even though they are considered as independent different technologies, both can be described as time-dependent processes. AWJM can be considered as a continuous process and the etched material depends on the feed speed of the jet at each instant during the process. On the other hand, PLA processes are usually defined as discrete systems and the total removed material is calculated by the summation of the different pulses shot during the process. The overlapping of these shots depends on the feed speed and the frequency between two consecutive shots. However, if the feed speed is sufficiently slow compared with the frequency, then consecutive shots are close enough and the behaviour can be similar to a continuous process. Using this approximation a generic continuous model can be described for both processes. The inverse problem is usually solved for this kind of process by simply controlling dwell time in proportion to the required depth of milling at each single pixel on the surface using a linear model of the process. However, this approach does not always lead to the good solution since linear models are only valid when shallow surfaces are etched. The solution of the inverse problem is improved by using a discrete adjoint optimization algorithm. Moreover, the calculation of the Jacobian matrix consumes less computation time than finite difference approaches. The influence of the dynamics of the machine on the actual movement of the jet is also important and should be taken into account. When the parameters of the controller are not known or cannot be changed, a simple approximation is used for the choice of the slope of a step profile. Several experimental tests are performed for both technologies to show the usefulness of this approach.

Keywords: abrasive waterjet machining, energy beam processes, inverse problem, pulsed laser ablation

Procedia PDF Downloads 265
993 Sustainable Development and Modern Challenges of Higher Educational Institutions in the Regions of Georgia

Authors: Natia Tsiklashvili, Tamari Poladashvili

Abstract:

Education is one of the fundamental factors of economic prosperity in all respects. It is impossible to talk about the sustainable economic development of the country without substantial investments in human capital and investment into higher educational institutions. Education improves the standard of living of the population and expands the opportunities to receive more benefits, which will be equally important for both the individual and the society as a whole. There are growing initiatives among educated people such as entrepreneurship, technological development, etc. At the same time, the distribution of income between population groups is improving. The given paper discusses the scientific literature in the field of sustainable development through higher educational institutions. Scholars of economic theory emphasize a few major aspects that show the role of higher education in economic growth: a) Alongside education, human capital gradually increases which leads to increased competitiveness of the labor force, not only in the national but also in the international labor market (Neoclassical growth theory), b) The high level of education can increase the efficiency of the economy, investment in human capital, innovation, and knowledge are significant contributors to economic growth. Hence, it focuses on positive externalities and spillover effects of a knowledge-based economy which leads to economic development (endogenous growth theory), c) Education can facilitate the diffusion and transfer of knowledge. Hence, it supports macroeconomic sustainability and microeconomic conditions of individuals. While discussing the economic importance of education, we consider education as the spiritual development of the human that advances general skills, acquires a profession, and improves living conditions. Scholars agree that human capital is not only money but liquid assets, stocks, and competitive knowledge. The last one is the main lever in the context of increasing human competitiveness and high productivity. To address the local issues, the present article researched ten educational institutions across Georgia, including state and private HEIs. Qualitative research was done by analyzing in-depth interweaves of representatives from each institution, and respondents were rectors/vice-rectors/heads of quality assurance service at the institute. The result shows that there is a number of challenges that institution face in order to maintain sustainable development and be the strong links to education and the labor market. Mostly it’s contacted with bureaucracy, insufficient finances they receive, and local challenges that differ across the regions.

Keywords: higher education, higher educational institutions, sustainable development, regions, Georgia

Procedia PDF Downloads 72
992 A Theoretical Approach of Tesla Pump

Authors: Cristian Sirbu-Dragomir, Stefan-Mihai Sofian, Adrian Predescu

Abstract:

This paper aims to study Tesla pumps for circulating biofluids. It is desired to make a small pump for the circulation of biofluids. This type of pump will be studied because it has the following characteristics: It doesn’t have blades which results in very small frictions; Reduced friction forces; Low production cost; Increased adaptability to different types of fluids; Low cavitation (towards 0); Low shocks due to lack of blades; Rare maintenance due to low cavity; Very small turbulences in the fluid; It has a low number of changes in the direction of the fluid (compared to rotors with blades); Increased efficiency at low powers.; Fast acceleration; The need for a low torque; Lack of shocks in blades at sudden starts and stops. All these elements are necessary to be able to make a small pump that could be inserted into the thoracic cavity. The pump will be designed to combat myocardial infarction. Because the pump must be inserted in the thoracic cavity, elements such as Low friction forces, shocks as low as possible, low cavitation and as little maintenance as possible are very important. The operation should be performed once, without having to change the rotor after a certain time. Given the very small size of the pump, the blades of a classic rotor would be very thin and sudden starts and stops could cause considerable damage or require a very expensive material. At the same time, being a medical procedure, the low cost is important in order to be easily accessible to the population. The lack of turbulence or vortices caused by a classic rotor is again a key element because when it comes to blood circulation, the flow must be laminar and not turbulent. The turbulent flow can even cause a heart attack. Due to these aspects, Tesla's model could be ideal for this work. Usually, the pump is considered to reach an efficiency of 40% being used for very high powers. However, the author of this type of pump claimed that the maximum efficiency that the pump can achieve is 98%. The key element that could help to achieve this efficiency or one as close as possible is the fact that the pump will be used for low volumes and pressures. The key elements to obtain the best efficiency for this model are the number of rotors placed in parallel and the distance between them. The distance between them must be small, which helps to obtain a pump as small as possible. The principle of operation of such a rotor is to place in several parallel discs cut inside. Thus the space between the discs creates the vacuum effect by pulling the liquid through the holes in the rotor and throwing it outwards. Also, a very important element is the viscosity of the liquid. It dictates the distance between the disks to achieve a lossless power flow.

Keywords: lubrication, temperature, tesla-pump, viscosity

Procedia PDF Downloads 165
991 Non-Melanoma Skin Cancer of Cephalic Extremity – Clinical and Histological Aspects

Authors: Razvan Mercut, Mihaela Ionescu, Vlad Parvanescu, Razvan Ghita, Tudor-Gabriel Caragea, Cristina Simionescu, Marius-Eugen Ciurea

Abstract:

Introduction: Over the past years, the incidence of non-melanoma skin cancer (NMSC) has continuously increased, being one of the most commonly diagnosed carcinomasofthe cephalic extremity. NMSC regroups basal cell carcinoma (BCC), squamous cell carcinoma (SCC), Merkel cell carcinoma, cutaneous lymphoma, and sarcoma. The most common forms are BCC and SCC, both still implying a significant level of morbidity due to local invasion (especially BCC), even if the overall death rates are declining. The objective of our study was the evaluation of clinical and histological aspects of NMSC for a group of patients with BCC and SCC, from Craiova, a south-western major city in Romania. Materialand method: Our study lot comprised 65 patients, with an almost equal distribution of sexes, and ages between 23-91 years old (mean value±standard deviation62.61±16.67), all treated within the Clinic of Plastic Surgery and Reconstructive Microsurgery, Clinical Emergency County Hospital Craiova, Romania, between 2019-2020. In order to determine the main morphological characteristics of both studied cancers, we used paraffin embedding techniques, with various staining methods:hematoxylin-eosin, Masson's trichrome stain with aniline blue, and Periodic acid-schiffAlcian Blue. The statistical study was completed using Microsoft Excel (Microsoft Corp., Redmond, WA, USA), with XLSTAT (Addinsoft SARL, Paris, France). Results: The overall results of our study indicate that BCC accounts for 67.69% of all NMSC forms; SCC covers 27.69%, while 4.62% are representedby other forms. The most frequent site is the nose for BCC (27.69%, 18 patients), being followed by preauricular regions, forehead, and periorbital areas. For patients with SCC, tumors were mainly located at lips level (66.67%, 12 patients). The analysis of NMSC histological forms indicated that nodular BCC is predominant (45.45%, 20 patients), as well as ulcero-vegetant SCC (38.89%, 7 patients). We have not identified any topographic characteristics or NMSC forms significantly related to age or sex. Conclusions: The most frequent NMSC form identified for our study lot was BCC. The preferred location was the nose for BCC. For SCC, the oral cavity is the most frequent anatomical site, especially the lips level. Nodular BCC and ulcero-vegetant SCC were the most commonly identified histological types. Our findings emphasize the need for periodic screening, in order to improve prevention and early treatment for these malignancies.

Keywords: non-melanoma skin cancer, basal cell carcinoma, squamous cell carcinoma, histological

Procedia PDF Downloads 165
990 Influence of Thermal Ageing on Microstructural Features and Mechanical Properties of Reduced Activation Ferritic/Martensitic Grades

Authors: Athina Puype, Lorenzo Malerba, Nico De Wispelaere, Roumen Petrov, Jilt Sietsma

Abstract:

Reduced Activation Ferritic/Martensitic (FM) steels like EUROFER are of interest for first wall application in the future demonstration (DEMO) fusion reactor. Depending on the final design codes for the DEMO reactor, the first wall material will have to function in low-temperature mode or high-temperature mode, i.e. around 250-300°C of above 550°C respectively. However, the use of RAFM steels is limited up to a temperature of about 550°C. For the low-temperature application, the material suffers from irradiation embrittlement, due to a shift of ductile-to-brittle transition temperature (DBTT) towards higher temperatures upon irradiation. The high-temperature response of the material is equally insufficient for long-term use in fusion reactors, due to the instability of the matrix phase and coarsening of the precipitates at prolonged high-temperature exposure. The objective of this study is to investigate the influence of thermal ageing for 1000 hrs and 4000 hrs on microstructural features and mechanical properties of lab-cast EUROFER. Additionally, the ageing behavior of the lab-cast EUROFER is compared with the ageing behavior of standard EUROFER97-2 and T91. The microstructural features were investigated with light optical microscopy (LOM), electron back-scattered diffraction (EBSD) and transmission electron microscopy (TEM). Additionally, hardness measurements, tensile tests at elevated temperatures and Charpy V-notch impact testing of KLST-type MCVN specimens were performed to study the microstructural features and mechanical properties of four different F/M grades, i.e. T91, EUROFER97-2 and two lab-casted EUROFER grades. After ageing for 1000 hrs, the microstructures exhibit similar martensitic block sizes independent on the grain size before ageing. With respect to the initial coarser microstructures, the aged microstructures displayed a dislocation structure which is partially fragmented by polygonization. On the other hand, the initial finer microstructures tend to be more stable up to 1000hrs resulting in similar grain sizes for the four different steels. Increasing the ageing time to 4000 hrs, resulted in an increase of lath thickness and coarsening of M23C6 precipitates leading to a deterioration of tensile properties.

Keywords: ageing experiments, EUROFER, ferritic/martensitic steels, mechanical properties, microstructure, T91

Procedia PDF Downloads 244
989 Geological Characteristics and Hydrocarbon Potential of M’Rar Formation Within NC-210, Atshan Saddle Ghadamis-Murzuq Basins, Libya

Authors: Sadeg M. Ghnia, Mahmud Alghattawi

Abstract:

The NC-210 study area is located in Atshan Saddle between both Ghadamis and Murzuq basins, west Libya. The preserved Palaeozoic successions are predominantly clastics reaching thickness of more than 20,000 ft in northern Ghadamis Basin depocenter. The Carboniferous series consist of interbedded sandstone, siltstone, shale, claystone and minor limestone deposited in a fluctuating shallow marine to brackish lacustrine/fluviatile environment which attain maximum thickness of over 5,000ft in the area of Atshan Saddle and recorded 3,500 ft. in outcrops of Murzuq Basin flanks. The Carboniferous strata was uplifted and eroded during Late Paleozoic and early Mesozoic time in northern Ghadamis Basin and Atshan Saddle. The M'rar Formation age is Tournaisian to Late Serpukhovian based on palynological markers and contains about 12 cycles of sandstone and shale deposited in shallow to outer neritic deltaic settings. The hydrocarbons in the M'rar reservoirs possibly sourced from the Lower Silurian and possibly Frasinian radioactive hot shales. The M'rar Formation lateral, vertical and thickness distribution is possibly influenced by the reactivation of Tumarline Strik-Slip fault and its conjugate faults. A pronounced structural paleohighs and paleolows, trending SE & NW through the Gargaf Saddle, is possibly indicative of the present of two sub-basins in the area of Atshan Saddle. A number of identified seismic reflectors from existing 2D seismic covering Atshan Saddle reflect M’rar deltaic 12 sandstone cycles. M’rar7, M’rar9, M’rar10 and M’rar12 are characterized by high amplitude reflectors, while M’rar2 and M’rar6 are characterized by medium amplitude reflectors. These horizons are productive reservoirs in the study area. Available seismic data in the study area contributed significantly to the identification of M’rar potential traps, which are prominently 3- way dip closure against fault zone. Also seismic data indicates the presence of a significant strikeslip component with the development of flower-structure. The M'rar Formation hydrocarbon discoveries are concentrated mainly in the Atshan Saddle located in southern Ghadamis Basin, Libya and Illizi Basin in southeast of Algeria. Significant additional hydrocarbons may be present in areas adjacent to the Gargaf Uplift, along structural highs and fringing the Hoggar Uplift, providing suitable migration pathways.

Keywords: hydrocarbon potential, stratigraphy, Ghadamis basin, seismic, well data integration

Procedia PDF Downloads 54
988 Epoxomicin Affects Proliferating Neural Progenitor Cells of Rat

Authors: Bahaa Eldin A. Fouda, Khaled N. Yossef, Mohamed Elhosseny, Ahmed Lotfy, Mohamed Salama, Mohamed Sobh

Abstract:

Developmental neurotoxicity (DNT) entails the toxic effects imparted by various chemicals on the brain during the early childhood period. As human brains are vulnerable during this period, various chemicals would have their maximum effects on brains during early childhood. Some toxicants have been confirmed to induce developmental toxic effects on CNS e.g. lead, however; most of the agents cannot be identified with certainty due the defective nature of predictive toxicology models used. A novel alternative method that can overcome most of the limitations of conventional techniques is the use of 3D neurospheres system. This in-vitro system can recapitulate most of the changes during the period of brain development making it an ideal model for predicting neurotoxic effects. In the present study, we verified the possible DNT of epoxomicin which is a naturally occurring selective proteasome inhibitor with anti-inflammatory activity. Rat neural progenitor cells were isolated from rat embryos (E14) extracted from placental tissue. The cortices were aseptically dissected out from the brains of the fetuses and the tissues were triturated by repeated passage through a fire-polished constricted Pasteur pipette. The dispersed tissues were allowed to settle for 3 min. The supernatant was, then, transferred to a fresh tube and centrifuged at 1,000 g for 5 min. The pellet was placed in Hank’s balanced salt solution cultured as free-floating neurospheres in proliferation medium. Two doses of epoxomicin (1µM and 10µM) were used in cultured neuropsheres for a period of 14 days. For proliferation analysis, spheres were cultured in proliferation medium. After 0, 4, 5, 11, and 14 days, sphere size was determined by software analyses. The diameter of each neurosphere was measured and exported to excel file further to statistical analysis. For viability analysis, trypsin-EDTA solution were added to neurospheres for 3 min to dissociate them into single cells suspension, then viability evaluated by the Trypan Blue exclusion test. Epoxomicin was found to affect proliferation and viability of neuropsheres, these effects were positively correlated to doses and progress of time. This study confirms the DNT effects of epoxomicin on 3D neurospheres model. The effects on proliferation suggest possible gross morphologic changes while the decrease in viability propose possible focal lesion on exposure to epoxomicin during early childhood.

Keywords: neural progentor cells, epoxomicin, neurosphere, medical and health sciences

Procedia PDF Downloads 404
987 Experiment-Based Teaching Method for the Varying Frictional Coefficient

Authors: Mihaly Homostrei, Tamas Simon, Dorottya Schnider

Abstract:

The topic of oscillation in physics is one of the key ideas which is usually taught based on the concept of harmonic oscillation. It can be an interesting activity to deal with a frictional oscillator in advanced high school classes or in university courses. Its mechanics are investigated in this research, which shows that the motion of the frictional oscillator is more complicated than a simple harmonic oscillator. The physics of the applied model in this study seems to be interesting and useful for undergraduate students. The study presents a well-known physical system, which is mostly discussed theoretically in high school and at the university. The ideal frictional oscillator is normally used as an example of harmonic oscillatory motion, as its theory relies on the constant coefficient of sliding friction. The structure of the system is simple: a rod with a homogeneous mass distribution is placed on two rotating identical cylinders placed at the same height so that they are horizontally aligned, and they rotate at the same angular velocity, however in opposite directions. Based on this setup, one could easily show that the equation of motion describes a harmonic oscillation considering the magnitudes of the normal forces in the system as the function of the position and the frictional forces with a constant coefficient of frictions are related to them. Therefore, the whole description of the model relies on simple Newtonian mechanics, which is available for students even in high school. On the other hand, the phenomenon of the described frictional oscillator does not seem to be so straightforward after all; experiments show that the simple harmonic oscillation cannot be observed in all cases, and the system performs a much more complex movement, whereby the rod adjusts itself to a non-harmonic oscillation with a nonzero stable amplitude after an unconventional damping effect. The stable amplitude, in this case, means that the position function of the rod converges to a harmonic oscillation with a constant amplitude. This leads to the idea of a more complex model which can describe the motion of the rod in a more accurate way. The main difference to the original equation of motion is the concept that the frictional coefficient varies with the relative velocity. This dependence on the velocity was investigated in many different research articles as well; however, this specific problem could demonstrate the key concept of the varying friction coefficient and its importance in an interesting and demonstrative way. The position function of the rod is described by a more complicated and non-trivial, yet more precise equation than the usual harmonic oscillation description of the movement. The study discusses the structure of the measurements related to the frictional oscillator, the qualitative and quantitative derivation of the theory, and the comparison of the final theoretical function as well as the measured position-function in time. The project provides useful materials and knowledge for undergraduate students and a new perspective in university physics education.

Keywords: friction, frictional coefficient, non-harmonic oscillator, physics education

Procedia PDF Downloads 179
986 Analysis of Epileptic Electroencephalogram Using Detrended Fluctuation and Recurrence Plots

Authors: Mrinalini Ranjan, Sudheesh Chethil

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Epilepsy is a common neurological disorder characterised by the recurrence of seizures. Electroencephalogram (EEG) signals are complex biomedical signals which exhibit nonlinear and nonstationary behavior. We use two methods 1) Detrended Fluctuation Analysis (DFA) and 2) Recurrence Plots (RP) to capture this complex behavior of EEG signals. DFA considers fluctuation from local linear trends. Scale invariance of these signals is well captured in the multifractal characterisation using detrended fluctuation analysis (DFA). Analysis of long-range correlations is vital for understanding the dynamics of EEG signals. Correlation properties in the EEG signal are quantified by the calculation of a scaling exponent. We report the existence of two scaling behaviours in the epileptic EEG signals which quantify short and long-range correlations. To illustrate this, we perform DFA on extant ictal (seizure) and interictal (seizure free) datasets of different patients in different channels. We compute the short term and long scaling exponents and report a decrease in short range scaling exponent during seizure as compared to pre-seizure and a subsequent increase during post-seizure period, while the long-term scaling exponent shows an increase during seizure activity. Our calculation of long-term scaling exponent yields a value between 0.5 and 1, thus pointing to power law behaviour of long-range temporal correlations (LRTC). We perform this analysis for multiple channels and report similar behaviour. We find an increase in the long-term scaling exponent during seizure in all channels, which we attribute to an increase in persistent LRTC during seizure. The magnitude of the scaling exponent and its distribution in different channels can help in better identification of areas in brain most affected during seizure activity. The nature of epileptic seizures varies from patient-to-patient. To illustrate this, we report an increase in long-term scaling exponent for some patients which is also complemented by the recurrence plots (RP). RP is a graph that shows the time index of recurrence of a dynamical state. We perform Recurrence Quantitative analysis (RQA) and calculate RQA parameters like diagonal length, entropy, recurrence, determinism, etc. for ictal and interictal datasets. We find that the RQA parameters increase during seizure activity, indicating a transition. We observe that RQA parameters are higher during seizure period as compared to post seizure values, whereas for some patients post seizure values exceeded those during seizure. We attribute this to varying nature of seizure in different patients indicating a different route or mechanism during the transition. Our results can help in better understanding of the characterisation of epileptic EEG signals from a nonlinear analysis.

Keywords: detrended fluctuation, epilepsy, long range correlations, recurrence plots

Procedia PDF Downloads 161
985 Mapping Forest Biodiversity Using Remote Sensing and Field Data in the National Park of Tlemcen (Algeria)

Authors: Bencherif Kada

Abstract:

In forest management practice, landscape and Mediterranean forest are never posed as linked objects. But sustainable forestry requires the valorization of the forest landscape and this aim involves assessing the spatial distribution of biodiversity by mapping forest landscaped units and subunits and by monitoring the environmental trends. This contribution aims to highlight, through object-oriented classifications, the landscaped biodiversity of the National Park of Tlemcen (Algeria). The methodology used is based on ground data and on the basic processing units of object-oriented classification that are segments, so-called image-objects, representing a relatively homogenous units on the ground. The classification of Landsat Enhanced Thematic Mapper plus (ETM+) imagery is performed on image objects, and not on pixels. Advantages of object-oriented classification are to make full use of meaningful statistic and texture calculation, uncorrelated shape information (e.g., length-to-width ratio, direction and area of an object, etc.) and topological features (neighbor, super-object, etc.), and the close relation between real-world objects and image objects. The results show that per object classification using the k-nearest neighbor’s method is more efficient than per pixel one. It permits to simplify the content of the image while preserving spectrally and spatially homogeneous types of land covers such as Aleppo pine stands, cork oak groves, mixed groves of cork oak, holm oak and zen oak, mixed groves of holm oak and thuja, water plan, dense and open shrub-lands of oaks, vegetable crops or orchard, herbaceous plants and bare soils. Texture attributes seem to provide no useful information while spatial attributes of shape, compactness seem to be performant for all the dominant features, such as pure stands of Aleppo pine and/or cork oak and bare soils. Landscaped sub-units are individualized while conserving the spatial information. Continuously dominant dense stands over a large area were formed into a single class, such as dense, fragmented stands with clear stands. Low shrublands formations and high wooded shrublands are well individualized but with some confusion with enclaves for the former. Overall, a visual evaluation of the classification shows that the classification reflects the actual spatial state of the study area at the landscape level.

Keywords: forest, oaks, remote sensing, biodiversity, shrublands

Procedia PDF Downloads 10
984 The Features of the Synergistic Approach in Marketing Management to Regional Level

Authors: Evgeni Baratashvili, Anzor Abralava, Rusudan Kutateladze, Nino Pailodze, Irma Makharashvili, Larisa Takalandze

Abstract:

Sinergy as a neological term is reflected in modern sciences. It can be found in the various fields of science including the humanities and technical sciences. Among them are biology and medicine, philology, economy and etc. Synergy is the received surplus of marginal high total effect of the groups, consolidated by one common idea, received through endeavored applies of their combined tools, via obtained effect of the separate independent actions of the groups. In the conditions of market economy, according the terms of new communication terminology, synergy effects on management and marketing successfully as well as on purity defense of native language. The well-known scientist’s and public figure’s Academician I. Prangishvili’s works are especially valuable in this aspect. In our opinion the entropy research is linked to his name in our country. In modern economy, the current qualitative changes shows us that the most number of factors and issues have been regrouped. They have a great influence and even define the economic development. The declining abilities of traditional recourses of economic growth have been related on the use of their physical abilities and their moving closer to the edge. Also it is related on the reduced effectiveness, which at the same time increases the expenditures. This means that the leading must be the innovative process system of products and services in the economic growth model. In our opinion the above mentioned system is distinguished with the synergistic approach. It should be noted that the main components of the innovative system are technological, scientific and scientific-technical, social-organizational, managerial and cognitive changes. All of them are reflected on scientific works and inventions in the proper dosages, in know-how and material source. At any stage they create the reproduction cycle. The innovations are different from each other by technologies, origination, design, innovation and quality, subject-content structure, by the the spread of economic processes and the impact of the level of it’s distribution. We have presented a generalized statement of an innovative approach, which is not a single act of innovation but it is also targeted system of the development, implementation, reconciling-exploitation, production, diffusion and commercialization of news. The innovative approaches should be considered as the creation of news, in-depth process of creativity as an innovative alternative to the realization of innovative and entrepreneurial efforts and measures, in order to meet the requirements of the permanent process.

Keywords: economic development, leading process, neological term, synergy

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983 MCD-017: Potential Candidate from the Class of Nitroimidazoles to Treat Tuberculosis

Authors: Gurleen Kour, Mowkshi Khullar, B. K. Chandan, Parvinder Pal Singh, Kushalava Reddy Yumpalla, Gurunadham Munagala, Ram A. Vishwakarma, Zabeer Ahmed

Abstract:

New chemotherapeutic compounds against multidrug-resistant Mycobacterium tuberculosis (Mtb) are urgently needed to combat drug resistance in tuberculosis (TB). Apart from in-vitro potency against the target, physiochemical properties and pharmacokinetic properties play an imperative role in the process of drug discovery. We have identified novel nitroimidazole derivatives with potential activity against mycobacterium tuberculosis. One lead candidates, MCD-017, which showed potent activity against H37Rv strain (MIC=0.5µg/ml) and was further evaluated in the process of drug development. Methods: Basic physicochemical parameters like solubility and lipophilicity (LogP) were evaluated. Thermodynamic solubility was determined in PBS buffer (pH 7.4) using LC/MS-MS. The partition coefficient (Log P) of the compound was determined between octanol and phosphate buffered saline (PBS at pH 7.4) at 25°C by the microscale shake flask method. The compound followed Lipinski’s rule of five, which is predictive of good oral bioavailability and was further evaluated for metabolic stability. In-vitro metabolic stability was determined in rat liver microsomes. The hepatotoxicity of the compound was also determined in HepG2 cell line. In vivo pharmacokinetic profile of the compound after oral dosing was also obtained using balb/c mice. Results: The compound exhibited favorable solubility and lipophilicity. The physical and chemical properties of the compound were made use of as the first determination of drug-like properties. The compound obeyed Lipinski’s rule of five, with molecular weight < 500, number of hydrogen bond donors (HBD) < 5 and number of hydrogen bond acceptors(HBA) not more then 10. The log P of the compound was less than 5 and therefore the compound is predictive of exhibiting good absorption and permeation. Pooled rat liver microsomes were prepared from rat liver homogenate for measuring the metabolic stability. 99% of the compound was not metabolized and remained intact. The compound did not exhibit cytoxicity in hepG2 cells upto 40 µg/ml. The compound revealed good pharmacokinetic profile at a dose of 5mg/kg administered orally with a half life (t1/2) of 1.15 hours, Cmax of 642ng/ml, clearance of 4.84 ml/min/kg and a volume of distribution of 8.05 l/kg. Conclusion : The emergence of multi drug resistance (MDR) and extensively drug resistant (XDR) Tuberculosis emphasize the requirement of novel drugs active against tuberculosis. Thus, the need to evaluate physicochemical and pharmacokinetic properties in the early stages of drug discovery is required to reduce the attrition associated with poor drug exposure. In summary, it can be concluded that MCD-017 may be considered a good candidate for further preclinical and clinical evaluations.

Keywords: mycobacterium tuberculosis, pharmacokinetics, physicochemical properties, hepatotoxicity

Procedia PDF Downloads 440
982 Selection of Qualitative Research Strategy for Bullying and Harassment in Sport

Authors: J. Vveinhardt, V. B. Fominiene, L. Jeseviciute-Ufartiene

Abstract:

Relevance of Research: Qualitative research is still regarded as highly subjective and not sufficiently scientific in order to achieve objective research results. However, it is agreed that a qualitative study allows revealing the hidden motives of the research participants, creating new theories, and highlighting the field of problem. There is enough research done to reveal these qualitative research aspects. However, each research area has its own specificity, and sport is unique due to the image of its participants, who are understood as strong and invincible. Therefore, a sport participant might have personal issues to recognize himself as a victim in the context of bullying and harassment. Accordingly, researcher has a dilemma in general making to speak a victim in sport. Thus, ethical aspects of qualitative research become relevant. The plenty fields of sport make a problem determining the sample size of research. Thus, the corresponding problem of this research is which and why qualitative research strategies are the most suitable revealing the phenomenon of bullying and harassment in sport. Object of research is qualitative research strategy for bullying and harassment in sport. Purpose of the research is to analyze strategies of qualitative research selecting suitable one for bullying and harassment in sport. Methods of research were scientific research analyses of qualitative research application for bullying and harassment research. Research Results: Four mane strategies are applied in the qualitative research; inductive, deductive, retroductive, and abductive. Inductive and deductive strategies are commonly used researching bullying and harassment in sport. The inductive strategy is applied as quantitative research in order to reveal and describe the prevalence of bullying and harassment in sport. The deductive strategy is used through qualitative methods in order to explain the causes of bullying and harassment and to predict the actions of the participants of bullying and harassment in sport and the possible consequences of these actions. The most commonly used qualitative method for the research of bullying and harassment in sports is semi-structured interviews in speech and in written. However, these methods may restrict the openness of the participants in the study when recording on the dictator or collecting incomplete answers when the participant in the survey responds in writing because it is not possible to refine the answers. Qualitative researches are more prevalent in terms of technology-defined research data. For example, focus group research in a closed forum allows participants freely interact with each other because of the confidentiality of the selected participants in the study. The moderator can purposefully formulate and submit problem-solving questions to the participants. Hence, the application of intelligent technology through in-depth qualitative research can help discover new and specific information on bullying and harassment in sport. Acknowledgement: This research is funded by the European Social Fund according to the activity ‘Improvement of researchers’ qualification by implementing world-class R&D projects of Measure No. 09.3.3-LMT-K-712.

Keywords: bullying, focus group, harassment, narrative, sport, qualitative research

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981 Investigations into the in situ Enterococcus faecalis Biofilm Removal Efficacies of Passive and Active Sodium Hypochlorite Irrigant Delivered into Lateral Canal of a Simulated Root Canal Model

Authors: Saifalarab A. Mohmmed, Morgana E. Vianna, Jonathan C. Knowles

Abstract:

The issue of apical periodontitis has received considerable critical attention. Bacteria is integrated into communities, attached to surfaces and consequently form biofilm. The biofilm structure provides bacteria with a series protection skills against, antimicrobial agents and enhances pathogenicity (e.g. apical periodontitis). Sodium hypochlorite (NaOCl) has become the irrigant of choice for elimination of bacteria from the root canal system based on its antimicrobial findings. The aim of the study was to investigate the effect of different agitation techniques on the efficacy of 2.5% NaOCl to eliminate the biofilm from the surface of the lateral canal using the residual biofilm, and removal rate of biofilm as outcome measures. The effect of canal complexity (lateral canal) on the efficacy of the irrigation procedure was also assessed. Forty root canal models (n = 10 per group) were manufactured using 3D printing and resin materials. Each model consisted of two halves of an 18 mm length root canal with apical size 30 and taper 0.06, and a lateral canal of 3 mm length, 0.3 mm diameter located at 3 mm from the apical terminus. E. faecalis biofilms were grown on the apical 3 mm and lateral canal of the models for 10 days in Brain Heart Infusion broth. Biofilms were stained using crystal violet for visualisation. The model halves were reassembled, attached to an apparatus and tested under a fluorescence microscope. Syringe and needle irrigation protocol was performed using 9 mL of 2.5% NaOCl irrigant for 60 seconds. The irrigant was either left stagnant in the canal or activated for 30 seconds using manual (gutta-percha), sonic and ultrasonic methods. Images were then captured every second using an external camera. The percentages of residual biofilm were measured using image analysis software. The data were analysed using generalised linear mixed models. The greatest removal was associated with the ultrasonic group (66.76%) followed by sonic (45.49%), manual (43.97%), and passive irrigation group (control) (38.67%) respectively. No marked reduction in the efficiency of NaOCl to remove biofilm was found between the simple and complex anatomy models (p = 0.098). The removal efficacy of NaOCl on the biofilm was limited to the 1 mm level of the lateral canal. The agitation of NaOCl results in better penetration of the irrigant into the lateral canals. Ultrasonic agitation of NaOCl improved the removal of bacterial biofilm.

Keywords: 3D printing, biofilm, root canal irrigation, sodium hypochlorite

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980 A Comparison of qCON/qNOX to the Bispectral Index as Indices of Antinociception in Surgical Patients Undergoing General Anesthesia with Laryngeal Mask Airway

Authors: Roya Yumul, Ofelia Loani Elvir-Lazo, Sevan Komshian, Ruby Wang, Jun Tang

Abstract:

BACKGROUND: An objective means for monitoring the anti-nociceptive effects of perioperative medications has long been desired as a way to provide anesthesiologists information regarding a patient’s level of antinociception and preclude any untoward autonomic responses and reflexive muscular movements from painful stimuli intraoperatively. To this end, electroencephalogram (EEG) based tools including BIS and qCON were designed to provide information about the depth of sedation while qNOX was produced to inform on the degree of antinociception. The goal of this study was to compare the reliability of qCON/qNOX to BIS as specific indicators of response to nociceptive stimulation. METHODS: Sixty-two patients undergoing general anesthesia with LMA were included in this study. Institutional Review Board (IRB) approval was obtained, and informed consent was acquired prior to patient enrollment. Inclusion criteria included American Society of Anesthesiologists (ASA) class I-III, 18 to 80 years of age, and either gender. Exclusion criteria included the inability to consent. Withdrawal criteria included conversion to the endotracheal tube and EEG malfunction. BIS and qCON/qNOX electrodes were simultaneously placed on all patients prior to induction of anesthesia and were monitored throughout the case, along with other perioperative data, including patient response to noxious stimuli. All intraoperative decisions were made by the primary anesthesiologist without influence from qCON/qNOX. Student’s t-distribution, prediction probability (PK), and ANOVA were used to statistically compare the relative ability to detect nociceptive stimuli for each index. Twenty patients were included for the preliminary analysis. RESULTS: A comparison of overall intraoperative BIS, qCON and qNOX indices demonstrated no significant difference between the three measures (N=62, p> 0.05). Meanwhile, index values for qNOX (62±18) were significantly higher than those for BIS (46±14) and qCON (54±19) immediately preceding patient responses to nociceptive stimulation in a preliminary analysis (N=20, * p= 0.0408). Notably, certain hemodynamic measurements demonstrated a significant increase in response to painful stimuli (MAP increased from 74 ±13 mm Hg at baseline to 84 ± 18 mm Hg during noxious stimuli [p= 0.032] and HR from 76 ± 12 BPM at baseline to 80 ± 13 BPM during noxious stimuli [p=0.078] respectively). CONCLUSION: In this observational study, BIS and qCON/qNOX provided comparable information on patients’ level of sedation throughout the course of an anesthetic. Meanwhile, increases in qNOX values demonstrated a superior correlation to an imminent response to stimulation relative to all other indices

Keywords: antinociception, BIS, general anesthesia, LMA, qCON/qNOX

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979 Applying the Quad Model to Estimate the Implicit Self-Esteem of Patients with Depressive Disorders: Comparing the Psychometric Properties with the Implicit Association Test Effect

Authors: Yi-Tung Lin

Abstract:

Researchers commonly assess implicit self-esteem with the Implicit Association Test (IAT). The IAT’s measure, often referred to as the IAT effect, indicates the strengths of automatic preferences for the self relative to others, which is often considered an index of implicit self-esteem. However, based on the Dual-process theory, the IAT does not rely entirely on the automatic process; it is also influenced by a controlled process. The present study, therefore, analyzed the IAT data with the Quad model, separating four processes on the IAT performance: the likelihood that automatic association is activated by the stimulus in the trial (AC); that a correct response is discriminated in the trial (D); that the automatic bias is overcome in favor of a deliberate response (OB); and that when the association is not activated, and the individual fails to discriminate a correct answer, there is a guessing or response bias drives the response (G). The AC and G processes are automatic, while the D and OB processes are controlled. The AC parameter is considered as the strength of the association activated by the stimulus, which reflects what implicit measures of social cognition aim to assess. The stronger the automatic association between self and positive valence, the more likely it will be activated by a relevant stimulus. Therefore, the AC parameter was used as the index of implicit self-esteem in the present study. Meanwhile, the relationship between implicit self-esteem and depression is not fully investigated. In the cognitive theory of depression, it is assumed that the negative self-schema is crucial in depression. Based on this point of view, implicit self-esteem would be negatively associated with depression. However, the results among empirical studies are inconsistent. The aims of the present study were to examine the psychometric properties of the AC (i.e., test-retest reliability and its correlations with explicit self-esteem and depression) and compare it with that of the IAT effect. The present study had 105 patients with depressive disorders completing the Rosenberg Self-Esteem Scale, Beck Depression Inventory-II and the IAT on the pretest. After at least 3 weeks, the participants completed the second IAT. The data were analyzed by the latent-trait multinomial processing tree model (latent-trait MPT) with the TreeBUGS package in R. The result showed that the latent-trait MPT had a satisfactory model fit. The effect size of test-retest reliability of the AC and the IAT effect were medium (r = .43, p < .0001) and small (r = .29, p < .01) respectively. Only the AC showed a significant correlation with explicit self-esteem (r = .19, p < .05). Neither of the two indexes was correlated with depression. Collectively, the AC parameter was a satisfactory index of implicit self-esteem compared with the IAT effect. Also, the present study supported the results that implicit self-esteem was not correlated with depression.

Keywords: cognitive modeling, implicit association test, implicit self-esteem, quad model

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978 Radar on Bike: Coarse Classification based on Multi-Level Clustering for Cyclist Safety Enhancement

Authors: Asma Omri, Noureddine Benothman, Sofiane Sayahi, Fethi Tlili, Hichem Besbes

Abstract:

Cycling, a popular mode of transportation, can also be perilous due to cyclists' vulnerability to collisions with vehicles and obstacles. This paper presents an innovative cyclist safety system based on radar technology designed to offer real-time collision risk warnings to cyclists. The system incorporates a low-power radar sensor affixed to the bicycle and connected to a microcontroller. It leverages radar point cloud detections, a clustering algorithm, and a supervised classifier. These algorithms are optimized for efficiency to run on the TI’s AWR 1843 BOOST radar, utilizing a coarse classification approach distinguishing between cars, trucks, two-wheeled vehicles, and other objects. To enhance the performance of clustering techniques, we propose a 2-Level clustering approach. This approach builds on the state-of-the-art Density-based spatial clustering of applications with noise (DBSCAN). The objective is to first cluster objects based on their velocity, then refine the analysis by clustering based on position. The initial level identifies groups of objects with similar velocities and movement patterns. The subsequent level refines the analysis by considering the spatial distribution of these objects. The clusters obtained from the first level serve as input for the second level of clustering. Our proposed technique surpasses the classical DBSCAN algorithm in terms of geometrical metrics, including homogeneity, completeness, and V-score. Relevant cluster features are extracted and utilized to classify objects using an SVM classifier. Potential obstacles are identified based on their velocity and proximity to the cyclist. To optimize the system, we used the View of Delft dataset for hyperparameter selection and SVM classifier training. The system's performance was assessed using our collected dataset of radar point clouds synchronized with a camera on an Nvidia Jetson Nano board. The radar-based cyclist safety system is a practical solution that can be easily installed on any bicycle and connected to smartphones or other devices, offering real-time feedback and navigation assistance to cyclists. We conducted experiments to validate the system's feasibility, achieving an impressive 85% accuracy in the classification task. This system has the potential to significantly reduce the number of accidents involving cyclists and enhance their safety on the road.

Keywords: 2-level clustering, coarse classification, cyclist safety, warning system based on radar technology

Procedia PDF Downloads 64
977 Examining the Investment Behavior of Arab Women in the Stock Market

Authors: Razan Salem

Abstract:

Gender plays a vital role in the stock markets because men and women differ in their behavior when investing in stocks. Accordingly, the role of gender differences in investment behavior is an increasingly important strand in the field of behavioral finance research. The investment behaviors of women relative to men have been examined in the behavioral finance literature, mainly for comparison purposes. Women's roles in the stock market have not been examined in the behavioral finance literature, however, particularly with respect to the Arab region. This study aims to contribute towards a better understanding of the investment behavior of Arab women (in regards to their risk tolerance, investment confidence, and investment literacy levels) relative to Arab men; using a sample from Arab women and men investors living in Saudi Arabia and Jordan. In order to achieve the study's main aim, the researcher used non-parametric tests, as Mann-Whitney U test, along with frequency distribution analysis to analyze the study’s primary data. The researcher distributed close-ended online questionnaires to a sample of 550 Arab male and female individuals investing in stocks in both Saudi Arabia and Jordan. The results confirm that the sample Arab women invest less in stocks compared to Arab men due to their risk-averse behaviors and limited confidence levels. The results also reveal that due to Arab women’s very low investment literacy levels, they fear from taking the risk and invest often in stocks relative to Arab men. Overall, the study’s main variables (risk tolerance, investment confidence, and investment literacy levels) have a combined effect on the investment behavior of Arab women and their limited participation in the stock market. Hence, this study is one of the very first studies that indicate the combined effect of the three main variables (which are usually studied separately in the existing literature) on the investment behavior of women, particularly Arab women. This study makes three important contributions to the growing literature on gender differences in investment behavior. First, while the behavioral finance literature documents evidence on gender differences in investment behaviors in many developed countries, there are very limited studies that investigate such differences in Arab countries. Arab women investors, generally, are ignored from the behavioral finance literature due probably to cultural barriers and data collection difficulties. Thus, this study extends the literature to include Arab women and their investment behaviors when trading stock relative to Arab men. Moreover, the study associates women investment literacy and confidence levels with their financial risk behaviors and participation in the stock market. This study provides direct evidence on Arab women's investment behaviors when trading stocks. Overall, studying Arab women investors is important to investigate whether the investment behavior identified for Western women investors are also found in Arab women investors.

Keywords: Arab women, gender differences, investment behavior, stock markets

Procedia PDF Downloads 164
976 Pooled Analysis of Three School-Based Obesity Interventions in a Metropolitan Area of Brazil

Authors: Rosely Sichieri, Bruna K. Hassan, Michele Sgambato, Barbara S. N. Souza, Rosangela A. Pereira, Edna M. Yokoo, Diana B. Cunha

Abstract:

Obesity is increasing at a fast rate in low and middle-income countries where few school-based obesity interventions have been conducted. Results of obesity prevention studies are still inconclusive mainly due to underestimation of sample size in cluster-randomized trials and overestimation of changes in body mass index (BMI). The pooled analysis in the present study overcomes these design problems by analyzing 4,448 students (mean age 11.7 years) from three randomized behavioral school-based interventions, conducted in public schools of the metropolitan area of Rio de Janeiro, Brazil. The three studies focused on encouraging students to change their drinking and eating habits over one school year, with monthly 1-h sessions in the classroom. Folders explaining the intervention program and suggesting the participation of the family, such as reducing the purchase of sodas were sent home. Classroom activities were delivered by research assistants in the first two interventions and by the regular teachers in the third one, except for culinary class aimed at developing cooking skills to increase healthy eating choices. The first intervention was conducted in 2005 with 1,140 fourth graders from 22 public schools; the second, with 644 fifth graders from 20 public schools in 2010; and the last one, with 2,743 fifth and sixth graders from 18 public schools in 2016. The result was a non-significant change in BMI after one school year of positive changes in dietary behaviors associated with obesity. Pooled intention-to-treat analysis using linear mixed models was used for the overall and subgroup analysis by BMI status, sex, and race. The estimated mean BMI changes were from 18.93 to 19.22 in the control group and from 18.89 to 19.19 in the intervention group; with a p-value of change over time of 0.94. Control and intervention groups were balanced at baseline. Subgroup analyses were statistically and clinically non-significant, except for the non-overweight/obese group with a 0.05 reduction of BMI comparing the intervention with control. In conclusion, this large pooled analysis showed a very small effect on BMI only in the normal weight students. The results are in line with many of the school-based initiatives that have been promising in relation to modifying behaviors associated with obesity but of no impact on excessive weight gain. Changes in BMI may require great changes in energy balance that are hard to achieve in primary prevention at school level.

Keywords: adolescents, obesity prevention, randomized controlled trials, school-based study

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975 The Impact of ESG Factors on Performance Measures in European Business

Authors: Raquel Pérez Estébanez

Abstract:

This research proposal seeks to delve into the intricate relationship between performance indicators and sustainability metrics within the realm of corporate entities. As businesses grapple with the imperative of sustainable practices, understanding how traditional performance metrics intersect with sustainability indicators becomes paramount. This study endeavours to unravel the dynamics of this relationship, aiming to illuminate ways in which these two sets of metrics can be harmoniously integrated to offer a comprehensive evaluation of a company's success while considering its environmental and societal impact. The integration of performance measures and sustainability metrics has become a focal point in contemporary business literature as companies strive to balance economic success with environmental and social responsibility. Performance indicators traditionally focus on financial metrics such as return on assets, return on equity and profitability. Sustainability metrics, on the other hand, encompass environmental, social, and governance (ESG) factors. The challenge lies in aligning these diverse metrics for a comprehensive assessment. Researches indicates a growing trend among corporations to incorporate sustainability metrics into their performance evaluations. However, challenges persist, with companies often struggling to integrate non-financial indicators seamlessly. The works of GRI (Global Reporting Initiative) and SASB (Sustainability Accounting Standards Board) propose frameworks for harmonizing financial and sustainability reporting. These frameworks emphasize the need for companies to disclose material sustainability information alongside traditional financial metrics. Several studies suggest that integrating sustainability metrics positively influences decision-making. Companies considering sustainability factors in decision-making exhibit improved long-term performance and risk management. Other researches highlights the increasing importance of sustainability metrics in shaping stakeholder perceptions. Investors, in particular, are placing greater emphasis on companies' environmental and social performance when making investment decisions. Industry-specific studies underscore the need for customized approaches to integration due to sector-specific challenges and opportunities. This suggests that a one-size-fits-all solution may not be applicable across diverse industries. While progress is evident, challenges persist, necessitating further research to refine integration frameworks, address industry-specific nuances, and assess the long-term impact on organizational performance and societal contributions.

Keywords: ESG, ROE, ROA, performance measures

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974 A Comparison between TM: TM Co Doped and TM: RE Co Doped ZnO Based Advanced Materials for Spintronics Applications; Structural, Optical and Magnetic Property Analysis

Authors: V. V. Srinivasu, Jayashree Das

Abstract:

Owing to the industrial and technological importance, transition metal (TM) doped ZnO has been widely chosen for many practical applications in electronics and optoelectronics. Besides, though still a controversial issue, the reported room temperature ferromagnetism in transition metal doped ZnO has added a feather to its excellence and importance in current semiconductor research for prospective application in Spintronics. Anticipating non controversial and improved optical and magnetic properties, we adopted co doping method to synthesise polycrystalline Mn:TM (Fe,Ni) and Mn:RE(Gd,Sm) co doped ZnO samples by solid state sintering route with compositions Zn1-x (Mn:Fe/Ni)xO and Zn1-x(Mn:Gd/Sm)xO and sintered at two different temperatures. The structure, composition and optical changes induced in ZnO due to co doping and sintering were investigated by XRD, FTIR, UV, PL and ESR studies. X-ray peak profile analysis (XPPA) and Williamson-Hall analysis carried out shows changes in the values of stress, strain, FWHM and the crystallite size in both the co doped systems. FTIR spectra also show the effect of both type of co doping on the stretching and bending bonds of ZnO compound. UV-Vis study demonstrates changes in the absorption band edge as well as the significant change in the optical band gap due to exchange interactions inside the system after co doping. PL studies reveal effect of co doping on UV and visible emission bands in the co doped systems at two different sintering temperatures, indicating the existence of defects in the form of oxygen vacancies. While the TM: TM co doped samples of ZnO exhibit ferromagnetism at room temperature, the TM: RE co doped samples show paramagnetic behaviour. The magnetic behaviours observed are supported by results from Electron Spin resonance (ESR) study; which shows sharp resonance peaks with considerable line width (∆H) and g values more than 2. Such values are usually found due to the presence of an internal field inside the system giving rise to the shift of resonance field towards the lower field. The g values in this range are assigned to the unpaired electrons trapped in oxygen vacancies. TM: TM co doped ZnO samples exhibit low field absorption peaks in their ESR spectra, which is a new interesting observation. We emphasize that the interesting observations reported in this paper may be considered for the improved futuristic applications of ZnO based materials.

Keywords: co-doping, electro spin resonance, microwave absorption, spintronics

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973 Co-Development of an Assisted Manual Harvesting Tool for Peach Palm That Avoids the Harvest in Heights

Authors: Mauricio Quintero Angel, Alexander Pereira, Selene Alarcón

Abstract:

One of the elements of greatest importance in agricultural production is the harvesting; an activity associated to different occupational health risks such as harvesting in high altitudes, the transport of heavy materials and the application of excessive muscle strain that leads to muscular-bone disorders. Therefore, there is an urgent necessity to improve and validate interventions to reduce exposition and risk to harvesters. This article has the objective of describing the co-development under the ergonomic analysis framework of an assisted manual harvesting tool for peach palm oriented to reduce the risk of death and accidents as it avoid the harvest in heights. The peach palm is a palm tree that is cultivated in Colombia, Perú, Brasil, Costa Rica, among others and that reaches heights of over 20 m, with stipes covered with spines. The fruits are drupes of variable size. For the harvesting of peach palm, in Colombia farmers use the “Marota” or “Climber”, a tool in a closed X shape built in wood, that has two supports adjusted at the stipe, that elevate alternately until reaching a point high enough to grab the bunch that is brought down using a rope. An activity of high risk since it is done at a high altitude without any type of protection and safety measures. The Marota is alternated with a rod, which as variable height between 5 and 12 Meters with a harness system at one end to hold the bunch that is lowered with the whole system (bamboo bunch). The rod is used from the ground or from the Marota in height. As an alternative to traditional tools, the Bajachonta was co-developed with farmers, a tool that employs a traditional bamboo hook system with modifications, to be able to hold it with a rope that passes through a pulley. Once the bunch is hitched, the hook system is detached and this stays attached to the peduncle of the palm tree, afterwards through a pulling force being exerted towards the ground by tensioning the rope, the bunch comes loose to be taken down using a rope and the pulley system to the ground, reducing the risk and efforts in the operation. The bajachonta was evaluated in tree productive zones of Colombia, with innovative farmers, were the adoption is highly probable, with some modifications to improve its efficiency and effectiveness, keeping in mind that the farmers perceive in it an advantage in the reduction of death and accidents by not having to harvest in heights.

Keywords: assisted harvesting, ergonomics, harvesting in high altitudes, participative design, peach palm

Procedia PDF Downloads 388
972 A Pilot Randomized Controlled Trial of a Physical Activity Intervention in a Low Socioeconomic Population: Focus on Mental Contrasting with Implementation Intentions

Authors: Shaun G. Abbott, Rebecca C. Reynolds, John B. F. de Wit

Abstract:

Low physical activity (PA) levels are a major public health concern in Australia. There is some evidence that PA interventions can increase PA levels via various methods, including online delivery. Low Socioeconomic Status (SES) people participate in less PA than the rest of the population, partly due to poor self-regulation behaviors associated with socioeconomic characteristics. Interventions that involve a particular method of self-regulation, Mental Contrasting with Implementation Intentions (MCII), has regularly achieved healthy behavior change, but few studies focus on PA behavior outcomes and no studies examining the effect of MCII on the PA behaviors of low SES people has been done. In this study, a pilot randomized controlled trial (RCT) will deliver MCII for PA behavior change to individuals of relative disadvantage for the first time. The current pilot study will predict sample size for a future full RCT and test the hypothesis that sedentary participants from areas of relative socioeconomic disadvantage of Sydney, who learn the MCII technique will be more physically active, have improved anthropometry and psychological indicators at the completion of a 12-week intervention compared to baseline and control. Eligible participants of relative socioeconomic disadvantage will be randomly assigned to either the ‘PA Information Plus MCII Intervention Group’ or a ‘PA Information-Only Control Group’. Both groups will attend a baseline and 12-week face-to-face consultation; where PA, anthropometric and psychological data will be gathered. The intervention group will be guided through an MCII session at the baseline appointment to establish a PA goal to aim to achieve over 12 weeks. Other than these baseline and 12-week consultations, all participant interaction will occur online. All participants will receive a ‘Fitbit’ accelerometer to record objectively. PA as a daily step count, along with a PA diary for the duration of the study. PA data will be recorded on a personalized online spreadsheet. Both groups will receive a standard PA information email at weeks 2, 4, and 8. The intervention group will also receive scripted follow-up online appointments to discuss goal progress. The current pilot study is in recruitment stage with findings to be presented at the conference in December if selected.

Keywords: implementation intentions, mental contrasting, motivation, pedometer, physical activity, socioeconomic

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971 The Concurrent Effect of Autistic and Schizotypal Traits on Convergent and Divergent Thinking

Authors: Ahmad Abu-Akel, Emilie De Montpellier, Sophie Von Bentivegni, Lyn Luechinger, Alessandro Ishii, Christine Mohr

Abstract:

Convergent and divergent thinking are two main components of creativity that have been viewed as complementary. While divergent thinking refers to the fluency and flexibility of generating new ideas, convergent thinking refers to the ability to systematically apply rules and knowledge to arrive at the optimal solution or idea. These creativity components have been shown to be susceptible to variation in subclinical expressions of autistic and schizotypal traits within the general population. Research, albeit inconclusively, mainly linked positive schizotypal traits with divergent thinking and autistic traits with convergent thinking. However, cumulative evidence suggests that these trait dimensions can co-occur in the same individual more than would be expected by chance and that their concurrent effect can be diametric and even interactive. The current study aimed at investigating the concurrent effect of these trait dimensions on tasks assessing convergent and divergent thinking abilities. We predicted that individuals with high positive schizotypal traits alone would perform particularly well on the divergent thinking task, whilst those with high autistic traits alone would perform particularly well on the convergent thinking task. Crucially, we also predicted that individuals who are high on both autistic and positive schizotypal traits would perform particularly well on both the divergent and convergent thinking tasks. This was investigated in a non-clinical sample of 142 individuals (Males = 45%; Mean age = 21.45, SD = 2.30), sufficient to minimally observe an effect size f² ≥ .10. Divergent thinking was evaluated using the Alternative Uses Task, and convergent thinking with the Anagrams Task. Autistic and schizotypal traits were respectively assessed with the Autism Quotient Questionnaire (AQ) and the Oxford-Liverpool Inventory of Feelings and Experiences (O-LIFE). Regression analyses revealed that the positive association of autistic traits with convergent thinking scores was qualified with an interaction with positive schizotypal traits. Specifically, positive schizotypal traits were negatively associated with convergent thinking scores when AQ scores were relatively low, but this trend was reversed when AQ scores were high. Conversely, the positive effect of AQ scores on convergent thinking progressively increased with increasing positive schizotypal traits. The results of divergent thinking task are currently being analyzed and will be reported at the conference. The association of elevated autistic and positive schizotypal traits with convergent thinking may represent a unique profile of creative thinkers who are able to simultaneously draw on trait-specific advantages conferred by autistic and positively schizotypal traits such as local and global processing. This suggests that main-effect models can tell an incomplete story regarding the effect of autistic and positive schizotypal traits on creativity-related processes. Future creativity research should consider their interaction and the benefits conferred by their co-presence.

Keywords: autism, schizotypy, convergent thinking, divergent thinking, comorbidity

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970 Genetic Diversity Analysis in Ecological Populations of Persian Walnut

Authors: Masoud Sheidai, Fahimeh Koohdar, Hashem Sharifi

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Juglans regia (L.) commonly known as Persian walnut of the genus Juglans L. (Juglandaceae) is one of the most important cultivated plant species due to its high-quality wood and edible nuts. The genetic diversity analysis is essential for conservation and management of tree species. Persian walnut is native from South-Eastern Europe to North-Western China through Tibet, Nepal, Northern India, Pakistan, and Iran. The species like Persian walnut, which has a wide range of geographical distribution, should harbor extensive genetic variability to adapt to environmental fluctuations they face. We aimed to study the population genetic structure of seven Persian walnut populations including three wild and four cultivated populations by using ISSR (Inter simple sequence repeats) and SRAP (Sequence related amplified polymorphism) molecular markers. We also aimed to compare the genetic variability revealed by ISSR neutral multilocus marker and rDNA ITS sequences. The studied populations differed in morphological features as the samples in each population were clustered together and were separate from the other populations. Three wild populations studied were placed close to each other. The mantel test after 5000 times permutation performed between geographical distance and morphological distance in Persian walnut populations produced significant correlation (r = 0.48, P = 0.002). Therefore, as the populations become farther apart, they become more divergent in morphological features. ISSR analysis produced 47 bands/ loci, while we obtained 15 SRAP bands. Gst and other differentiation statistics determined for these loci revealed that most of the ISSR and SRAP loci have very good discrimination power and can differentiate the studied populations. AMOVA performed for these loci produced a significant difference (< 0.05) supporting the above-said result. AMOVA produced significant genetic difference based on ISSR data among the studied populations (PhiPT = 0.52, P = 0.001). AMOVA revealed that 53% of the total variability is due to among population genetic difference, while 47% is due to within population genetic variability. The results showed that both multilocus molecular markers and ITS sequences can differentiate Persian walnut populations. The studied populations differed genetically and showed isolation by distance (IBD). ITS sequence based MP and Bayesian phylogenetic trees revealed that Iranian walnut cultivars form a distinct clade separated from the cultivars studied from elsewhere. Almost all clades obtained have high bootstrap value. The results indicated that a combination of multilpcus and sequencing molecular markers can be used in genetic differentiation of Persian walnut.

Keywords: genetic diversity, population, molecular markers, genetic difference

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969 Comparison between Experimental and Numerical Studies of Fully Encased Composite Columns

Authors: Md. Soebur Rahman, Mahbuba Begum, Raquib Ahsan

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Composite column is a structural member that uses a combination of structural steel shapes, pipes or tubes with or without reinforcing steel bars and reinforced concrete to provide adequate load carrying capacity to sustain either axial compressive loads alone or a combination of axial loads and bending moments. Composite construction takes the advantages of the speed of construction, light weight and strength of steel, and the higher mass, stiffness, damping properties and economy of reinforced concrete. The most usual types of composite columns are the concrete filled steel tubes and the partially or fully encased steel profiles. Fully encased composite column (FEC) provides compressive strength, stability, stiffness, improved fire proofing and better corrosion protection. This paper reports experimental and numerical investigations of the behaviour of concrete encased steel composite columns subjected to short-term axial load. In this study, eleven short FEC columns with square shaped cross section were constructed and tested to examine the load-deflection behavior. The main variables in the test were considered as concrete compressive strength, cross sectional size and percentage of structural steel. A nonlinear 3-D finite element (FE) model has been developed to analyse the inelastic behaviour of steel, concrete, and longitudinal reinforcement as well as the effect of concrete confinement of the FEC columns. FE models have been validated against the current experimental study conduct in the laboratory and published experimental results under concentric load. It has been observed that FE model is able to predict the experimental behaviour of FEC columns under concentric gravity loads with good accuracy. Good agreement has been achieved between the complete experimental and the numerical load-deflection behaviour in this study. The capacities of each constituent of FEC columns such as structural steel, concrete and rebar's were also determined from the numerical study. Concrete is observed to provide around 57% of the total axial capacity of the column whereas the steel I-sections contributes to the rest of the capacity as well as ductility of the overall system. The nonlinear FE model developed in this study is also used to explore the effect of concrete strength and percentage of structural steel on the behaviour of FEC columns under concentric loads. The axial capacity of FEC columns has been found to increase significantly by increasing the strength of concrete.

Keywords: composite, columns, experimental, finite element, fully encased, strength

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968 A Qualitative Exploration of the Socio-Cultural Determinants of Exclusive Breastfeeding Practice among Rural Mothers in Bindawa and Baure Local Government Areas, Katsina, North West Nigeria

Authors: Friday I. Joseph

Abstract:

Background: Nigeria has an under-five mortality rate that is 128 per 1000 live birth which is higher than the rate for the African region. Optimal breastfeeding practice has the potential to reduce under-five mortality by 13% in developing countries. However, documented exclusive breastfeeding rate in Nigeria from birth to six months is just 17%. Aim: To explore perceptions of the sociocultural factors that influence exclusive breastfeeding for six months among rural mothers in Bindawa and Baure Local Government Area (LGA), Katsina state, North West Nigeria, to inform policies, intervention or strategies to improve exclusive breastfeeding practice in Nigeria. Methods: The social constructionism-interpretivist epistemological approach informed the use of an exploratory study to understand mothers’ experiences and views. Twenty mothers, all from rural areas between 19-35 years old were conveniently sampled from two LGA in Katsina state, north –west Nigeria for semi-structured interviews. Sample size had representation of both Hausa and Fulani ethnic group. Thematic content analysis was utilized for analysis. Results: Three major themes emerged from the study: (1) Breastfeeding initiation - Immediate traditional newborn care practices, birth attendant, place of delivery, the perception of about colostrum determines how soon a mother initiate breastfeeding. (2) Exclusive breastfeeding and introduction of food-Motivation to sustain exclusive breastfeeding relies on the interplay between the obligation to perform traditional rites; mother’s awareness and family support. (3) Decision making about infant feeding – It is not independent of the influence of key social figures like the father, mother-in-law, traditional birth attendant and the health workers. Overall, in spite of awareness of exclusive breastfeeding benefits, mothers expressed concerns that they may not win their family support if they shared contrary views. Conclusions: Health promotion intervention should be tailored, taking cognizant and addressing the sociocultural barriers to the practice of optimal breastfeeding by a focused community and family-based participatory approach. Implementers of interventions should employ culture-sensitive approaches in community-based intervention.

Keywords: exclusive breastfeeding, perception, qualitative, sociocultural determinants

Procedia PDF Downloads 159