Search results for: significant stressed zone
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 18232

Search results for: significant stressed zone

17542 The Effects of Molecular and Climatic Variability on the Occurrence of Aspergillus Species and Aflatoxin Production in Commercial Maize from Different Agro-climatic Regions in South Africa

Authors: Nji Queenta Ngum, Mwanza Mulunda

Abstract:

Introduction Most African research reports on the frequent aflatoxin contamination of various foodstuffs, with researchers rarely specifying which of the Aspergillus species are present in these commodities. Numerous research works provide evidence of the ability of fungi to grow, thrive, and interact with other crop species and focus on the fact that these processes are largely affected by climatic variables. South Africa is a water-stressed country with high spatio-temporal rainfall variability; moreover, temperatures have been projected to rise at a rate twice the global rate. This weather pattern change may lead to crop stress encouraging mold contamination with subsequent mycotoxin production. In this study, the biodiversity and distribution of Aspergillus species with their corresponding toxins in maize from six distinct maize producing regions with different weather patterns in South Africa were investigated. Materials And Methods By applying cultural and molecular methods, a total of 1028 maize samples from six distinct agro-climatic regions were examined for contamination by the Aspergillus species while the high performance liquid chromatography (HPLC) method was applied to analyse the level of contamination by aflatoxins. Results About 30% of the overall maize samples were contaminated by at least one Aspergillus species. Less than 30% (28.95%) of the 228 isolates subjected to the aflatoxigenic test was found to possess at least one of the aflatoxin biosynthetic genes. Furthermore, almost 20% were found to be contaminated with aflatoxins, with mean total aflatoxin concentration levels of 64.17 ppb. Amongst the contaminated samples, 59.02% had mean total aflatoxin concentration levels above the SA regulatory limit of 20ppb for animals and 10 for human consumption. Conclusion In this study, climate variables (rainfall reduction) were found to significantly (p<0.001) influence the occurrence of the Aspergillus species (especially Aspergillus fumigatus) and the production of aflatoxin in South Africa commercial maize by maize variety, year of cultivation as well as the agro-climatic region in which the maize is cultivated. This included, amongst others, a reduction in the average annual rainfall of the preceding year to about 21.27 mm, and, as opposed to other regions whose average maximum rainfall ranged between 37.24 – 44.1 mm, resulted in a significant increase in the aflatoxin contamination of maize.

Keywords: aspergillus species, aflatoxins, diversity, drought, food safety, HPLC and PCR techniques

Procedia PDF Downloads 76
17541 Pharmacognostic, Phytochemical and Antibacterial Activity of Beaumontia Randiflora

Authors: Narmeen Mehmood

Abstract:

The current study was conducted to evaluate the pharmacognostic parameters, phytochemical analysis and antibacterial activity of the plant. Microscopic studies were carried out to determine various Pharmacognostic parameters. Section cutting of the leaf was also done. The study of the ariel parts of Beaumontia grandiflora resulted in the identification of fatty acids mixture and unsaponifiable matters. For the separation of various constituents of the plant, successive solvent extraction was carried out in a laboratory. Material and Methods: The study was carried out with all three extracts of Beaumontia grandiflora i.e. Petroleum ether, Chloroform and Methanol. For the separation of various constituents of the plant, successive solvent extraction was carried out in the laboratory. Raw data containing the measured zones of inhibition in mm was tabulated. Results: The microscopic studies showed the presence of Upper epidermis in surface view, Part of Lamina in section view, cortical parenchyma in longitudinal view, Parenchyma with collapsed tissues, Parenchyma Cells, Epidermal cells with a part of covering trichome, starch granules, reticulated thickened vessels, Transverse Section of leaf of Beaumontia grandiflora showed Upper Epidermis, Lower Epidermis, Hairs, Vascular Bundles, Parenchyma. Phytochemical analysis of leaves of Beaumontia grandiflora indicates that Alkaloids are present. There is a possibility of the presence of some bioactive components in the crude extracts due to which it shows strong activity. Petroleum ether extract shows a greater zone of inhibition at low concentrations. Conclusion: The alkaloids possess good antibacterial activity so the presence of alkaloids may be responsible for the antibacterial activity observed in the crude organic extract of Beaumontia grandiflora.

Keywords: successive solvent extraction, zone of inhibitions., microscopy, phytochemical analysis

Procedia PDF Downloads 21
17540 Torsional Rigidities of Reinforced Concrete Beams Subjected to Elastic Lateral Torsional Buckling

Authors: Ilker Kalkan, Saruhan Kartal

Abstract:

Reinforced concrete (RC) beams rarely undergo lateral-torsional buckling (LTB), since these beams possess large lateral bending and torsional rigidities owing to their stocky cross-sections, unlike steel beams. However, the problem of LTB is becoming more and more pronounced in the last decades as the span lengths of concrete beams increase and the cross-sections become more slender with the use of pre-stressed concrete. The buckling moment of a beam mainly depends on its lateral bending rigidity and torsional rigidity. The nonhomogeneous and elastic-inelastic nature of RC complicates estimation of the buckling moments of concrete beams. Furthermore, the lateral bending and torsional rigidities of RC beams and the buckling moments are affected from different forms of concrete cracking, including flexural, torsional and restrained shrinkage cracking. The present study pertains to the effects of concrete cracking on the torsional rigidities of RC beams prone to elastic LTB. A series of tests on rather slender RC beams indicated that torsional cracking does not initiate until buckling in elastic LTB, while flexural cracking associated with lateral bending takes place even at the initial stages of loading. Hence, the present study clearly indicated that the un-cracked torsional rigidity needs to be used for estimating the buckling moments of RC beams liable to elastic LTB.

Keywords: lateral stability, post-cracking torsional rigidity, uncracked torsional rigidity, critical moment

Procedia PDF Downloads 236
17539 The Passive Recipient – How the Pupil Comes across in Local Swedish Health Policy Documents

Authors: Zofia Hammerin, Goran Basic, Disa Bergnehr

Abstract:

Ever since the Ottawa charter in 1986, health promotion through schools has been stressed across the globe. Both in the global and national discourse, schools are made responsible not only for providing education but also for working with pupil health and well-being. In Sweden, where the study is set, it is emphasized in national directives that promoting pupil health should be part of the school practice. Since the Swedish school system is decentralized, these directives need to be interpreted and recontextualized locally. This study aims to explore how the student comes across in Swedish local health policy documents. The data consists of 37 such documents called student health plans collected from different high schools throughout Sweden. The analysis was inspired by critical discourse analysis, and tentative results are divided into two main themes; the invisible actor and the passive recipient. The pupil is largely invisible in the documents, and the discourse instead focuses on school health service staff and, to some extent, the teachers. When the pupils are visible, they mainly come across as passive recipients of health promoting actions. Since participation, taking action, and feeling empowered are key aspects of health promotion, the findings could impact the pupils’ possibilities for health and well-being.

Keywords: health promotion, high school, student, sweden

Procedia PDF Downloads 101
17538 Sewage Sludge Management: A Case Study of Monrovia, Montserrado County, Liberia

Authors: Victor Emery David Jr, Md S. Hossain

Abstract:

Sewage sludge management has been a problem faced by most developing cities as in the case of Monrovia. The management of sewage sludge in Monrovia is still in its infant stage. The city is still struggling with poor sanitation, clogged pipes, shortage of septic tanks, lack of resources/human capacity, inadequate treatment facilities, open defecation, the absence of clear guidelines, etc. The rapid urban population growth of Monrovia has severely stressed Monrovia’s marginally functional urban WSS system caused by the civil conflict which led to break down in many sectors as well as infrastructure. The sewerage system which originally covered 17% of the population of Monrovia was down to serving about 7% because of bursts and blockages causing backflows in other areas. Prior to the Civil War, the average water production for Monrovia was about 68,000 m3/day but has now dropped to about 10,000 m3/day. Only small parts of Monrovia currently have direct access to the piped water supply while most areas depend on trucked water delivered to community collection points or household tanks, and/or on water from unprotected dug wells or hand pumps. There are only two functional treatment plants; The Fiamah Treatment plant and the White Plains Treatment Plant.

Keywords: Fiamah Treatment plant, management, Monrovia/Montserrado County, sewage, sludge

Procedia PDF Downloads 289
17537 Strategic Analysis of Hospitality Marketing Driven by Culture in Historical City: Comparable Case Studies in Tainan City

Authors: Tsung-Han Lin, Chia-Han Yang

Abstract:

Recently, it’s obvious that many hotels not only provide customized service, but offer local culture to give customers different experiences. Luxury decoration and fancy equipment are not enough anymore. Customers expect that hotels not just as an accommodation, but connecting to their trips. Therefore, culture becomes significant when developing marketing strategy for hotels. Tainan, located in south of Taiwan, is the city full of culture that some hospitality industries promote their hotels exactly base on culture. Historic Tainan (台南; táinán), is a city of ancient monuments, delicious food and, above all, temples: there are more gods worshipped and more festivals and rituals observed in Tainan than in any other place in Taiwan. The oldest and most absorbing parts of Tainan are historic Anping, on the west side of town by the sea, and the cultural zones in the heart of the old city; the latter were created specifically to make things easier for visitors, with city information, signs and maps tailored to each zone and well-marked in English. The Chihkan, Dong-an Fang, Five Canals and Confucius Temple cultural zones contain the richest concentration of sights – reckon on spending at least two days to do them justice. As a result, the study aims to analyze the significance of culture on marketing strategies and C and H two hotels in Tainan city as case studies conducting the comparison of cultural marketing and experience marketing to provide a framework for hotels to develop their marketing strategies.

Keywords: cultural marketing, hospitality, historical city, Tainan city

Procedia PDF Downloads 451
17536 Competition in Petroleum Extraction and the Challenges of Climate Change

Authors: Saeid Rabiei Majd, Motahareh Alvandi, Bahareh Asefi

Abstract:

Extraction of maximum natural resources is one of the common policies of governments, especially petroleum resources that have high economic and strategic value. The incentive to access and maintain profitable oil markets for governments or international oil companies, causing neglects them to pay attention to environmental principles and sustainable development, which in turn drives up environmental and climate change. Significant damage to the environment can cause severe damage to citizens and indigenous people, such as the compulsory evacuation of their zone due to contamination of water and air resources, destruction of animals and plants. Hawizeh Marshes is a common aquatic and environmental ecosystem along the Iran-Iraq border that also has oil resources. This marsh has been very rich in animal, vegetative, and oil resources. Since 1990, the political motives, the strategic importance of oil extraction, and the disregard for the environmental rights of the Iraqi and Iranian governments in the region have caused 90% of the marshes and forced migration of indigenous people. In this paper, we examine the environmental degradation factors resulting from the adoption of policies and practices of governments in this region based on the principles of environmental rights and sustainable development. Revision of the implementation of the government’s policies and natural resource utilization systems can prevent the spread of climate change, which is a serious international challenge today.

Keywords: climate change, indigenous rights, petroleum operation, sustainable development principles, sovereignty on resources

Procedia PDF Downloads 111
17535 Growth of Nitella in Response to Cesium Exposure: Implication for Phytoremediation

Authors: Harun Rashid, Keerthi S. S. Atapaththu, Takashi Asaeda

Abstract:

Cesium (Cs) induced growth and stress response of Nitella were studied after exposure to four concentration of the metal; i.e. 0 (control), 0.001, 0.01, and 0.1 ppm Cs in growth media. Each treatment with three replicates were randomly allocated to 12 glass beakers in a complete randomize design and the experiment was continued for 30 days. At the end of the experiment, shoot length, cesium content, total chlorophyll, and plant stress response were compared. Anti-oxidant enzyme activities (peroxidase, catalase, and ascorbic peroxidase) and the concentration of H2O2 were measured to check plant stress. The longest shoot was found in control treatment (0 ppm Cs) and the shoot length of plants exposed to 0.001 ppm was statistically similar to that of control. Concentration of cesium in plants grown at 0.001, 0.01, and 0.1 ppm were significantly higher than those in control treatments. The antioxidant enzymes activities of plants exposed to cesium were significantly higher than those grown without any Cs (control). An elevated level of H2O2 concentration was also observed in former groups of plants. Further, the reduction in chlorophyll concentration and chlorophyll fluorescence in response to cesium exposure indicated the chronically damaged photosynthetic efficiency in cesium stressed Nitella.

Keywords: antioxidant enzymes, cesium, growth, Nitella, oxidative stress

Procedia PDF Downloads 425
17534 A Novel Hybrid Lubri-Coolant for Machining Difficult-to-Cut Ti-6Al-4V Alloy

Authors: Muhammad Jamil, Ning He, Wei Zhao

Abstract:

It is a rough estimation that the aerospace companies received orders of 37000 new aircraft, including the air ambulances, until 2037. And titanium alloys have a 15% contribution in modern aircraft's manufacturing owing to the high strength/weight ratio. Despite their application in the aerospace and medical equipment manufacturing industry, still, their high-speed machining puts a challenge in terms of tool wear, heat generation, and poor surface quality. Among titanium alloys, Ti-6Al-4V is the major contributor to aerospace application. However, its poor thermal conductivity (6.7W/mK) accumulates shear and friction heat at the tool-chip interface zone. To dissipate the heat generation and friction effect, cryogenic cooling, Minimum quantity lubrication (MQL), nanofluids, hybrid cryogenic-MQL, solid lubricants, etc., are applied frequently to underscore their significant effect on improving the machinability of Ti-6Al-4V. Nowadays, hybrid lubri-cooling is getting attention from researchers to explore their effect regarding the hard-to-cut Ti-6Al-4V. Therefore, this study is devoted to exploring the effect of hybrid ethanol-ester oil MQL regarding the cutting temperature, surface integrity, and tool life. As the ethanol provides -OH group and ester oil of long-chain molecules provide a tribo-film on the tool-workpiece interface. This could be a green manufacturing alternative for the manufacturing industry.

Keywords: hybrid lubri-cooling, surface roughness, tool wear, MQL

Procedia PDF Downloads 83
17533 Quantity, Quality and Water Productivity of Mulberry Leaf Influenced by Different Methods, Levels of Irrigation and Mulching in Eastern Dry Zone of Karnataka, India

Authors: Chengalappa Seenappa, Narayanappa Devkumar, Narayanappa Nagaraja

Abstract:

Mulberry leaf is the major economic component in sericulture and quality of leaf produced per unit area has a direct effect on quality of cocoon. Among all the agronomical inputs, irrigation water has highest impact on mulberry leaf quantity and quality. The water productivity in sericulture in the country is inadequate and inefficient though India has the largest irrigated area. There is a need of proper irrigation methods and conservation practices to ensure efficiency and economy in water use. Hence, this field experiment was conducted at College of Sericulture, Chintamani, Chickaballapur district, Karnataka, India during 2013 and 2014 to know the quantity, quality and water productivity of mulberry influenced by different methods, levels of irrigation and mulching in Eastern Dry Zone (EDZ) of Karnataka, India. The results revealed that the mulberry leaf quantity, quality and water productivity were significantly influenced by different methods, levels of irrigation and mulching. Subsurface drip irrigation at 0.8 CPE (Cumulative Pan Evaporation) recorded higher leaf yield, chlorophyll, relative water, protein content and water productivity (42857 kg ha-1 yr-1, 8.54, 65.80%, 22.27% and 364.41 kg hacm-1, respectively) than surface drip at 1.0 CPE (38809 kg ha-1 yr-1, 7.34, 62.76%, 17.75% and 264 10 kg hacm-1, respectively) and micro spray jet at 1.0 CPE (39931 kg ha-1 yr-1, 7.96, 63.50%, 19.00%, 35617 kg ha-1 yr-1 and 271.83 kg hacm-1, respectively). Mulching treatment recorded maximum leaf yield, chlorophyll, relative water, protein content and water productivity (38035 kg ha-1 yr-1, 7.12, 62.11%, 16.14% and 330 kg hacm-1, respectively) compared to without mulching. These results clearly indicated that subsurface drip irrigation at lower level of irrigation (0.8 CPE) and mulching increased the quantity, quality and water productivity of mulberry leaf than surface drip and micro spray jet irrigation at higher level of irrigation (1.0 CPE) by saving 20 per cent of water. Therefore, in the coming days subsurface drip irrigation in mulberry cultivation may be more appropriate to realise higher yield, quality and water productivity in EDZ of Karnataka, India.

Keywords: subsurface drip irrigation, mulching, water productivity, mulberry

Procedia PDF Downloads 269
17532 Impact of Climate Variability on Household's Crop Income in Central Highlands and Arssi Grain Plough Areas of Ethiopia

Authors: Arega Shumetie Ademe, Belay Kassa, Degye Goshu, Majaliwa Mwanjalolo

Abstract:

Currently the world economy is suffering from one critical problem, climate change. Some studies done before identified that impact of the problem is region specific means in some part of the world (temperate zone) there is improvement in agricultural performance but in some others like in the tropics there is drastic reduction in crop production and crop income. Climate variability is becoming dominant cause of short-term fluctuation in rain-fed agricultural production and income of developing countries. The purely rain-fed Ethiopian agriculture is the most vulnerable sector to the risks and impacts of climate variability. Thus, this study tried to identify impact of climate variability on crop income of smallholders in Ethiopia. The research used eight rounded unbalanced panel data from 1994- 2014 collected from six villages in the study area. After having all diagnostic tests the research used fixed effect method of regression. Based on the regression result rainfall and temperature deviation from their respective long term averages have negative and significant effect on crop income. Other extreme devastating shocks like flood, storm and frost, which are sourced from climate variability, have significant and negative effect on crop income of households’. Parameters that notify rainfall inconsistency like late start, variation in availability at growing season, and early cessation are critical problems for crop income of smallholder households as to the model result. Given this, impact of climate variability is not consistent in different agro-ecologies of the country. Rainfall variability has similar impact on crop income in different agro-ecology, but variation in temperature affects cold agro-ecology villages negatively and significantly, while it has positive effect in warm villages. Parameters that represent rainfall inconsistency have similar impact in both agro-ecologies and the aggregate model regression. This implies climate variability sourced from rainfall inconsistency is the main problem of Ethiopian agriculture especially the crop production sub-sector of smallholder households.

Keywords: climate variability, crop income, household, rainfall, temperature

Procedia PDF Downloads 376
17531 An Ethnographic Study: Ineffective Management of a Social Enterprise

Authors: Sylvia Acquah

Abstract:

The assumption that social enterprises are empowering has strong theoretical support, but empirical verification is anecdotal at best. Social enterprises blend social goal with an enterprising idea and therefore in theory these enterprises should provide meaningful jobs that are empowering. Whether jobs created are meaningful, or whether these organizations are practicing social entrepreneurship remains unexplored key questions. This paper addresses these key questions through a comprehensive literature review and an ethnographical study of a Domiciliary Home Care Social Enterprise in the UK. The social entrepreneurs, management and 9 staff members were observed, interviewed and achieves were reviewed and analyzed. In this study, the social entrepreneur’s vision was lost in transition during management change and the organization was only identified as a social enterprise by name. The organization that was set up to tackle lack of continuity in care and create a family of independent carers, was eventually closed down overnight and subjected to investigation by social services and the local council. Also, the ineffectiveness of the organization led to staff being stressed and without the support of the management to help rectify the issues; staff started displaying symptoms of burnout. Social enterprise managers should not only focus on profit maximization or generation, but should equally live up to the core tenets of the enterprise and effectively communicate and gain buy-in of all employees for any changes. Further, there ought to be an independent organization that regulates social enterprises to ensure that they are adhering to their social goals.

Keywords: ethnography, carer, social, enterprise

Procedia PDF Downloads 317
17530 The Use of Geographic Information System for Selecting Landfill Sites in Osogbo

Authors: Nureni Amoo, Sunday Aroge, Oluranti Akintola, Hakeem Olujide, Ibrahim Alabi

Abstract:

This study investigated the optimum landfill site in Osogbo so as to identify suitable solid waste dumpsite for proper waste management in the capital city. Despite an increase in alternative techniques for disposing of waste, landfilling remains the primary means of waste disposal. These changes in attitudes in many parts of the world have been supported by changes in laws and policies regarding the environment and waste disposal. Selecting the most suitable site for landfill can avoid any ecological and socio-economic effects. The increase in industrial and economic development, along with the increase of population growth in Osogbo town, generates a tremendous amount of solid waste within the region. Factors such as the scarcity of land, the lifespan of the landfill, and environmental considerations warrant that the scientific and fundamental studies are carried out in determining the suitability of a landfill site. The analysis of spatial data and consideration of regulations and accepted criteria are part of the important elements in the site selection. This paper presents a multi-criteria decision-making method using geographic information system (GIS) with the integration of the fuzzy logic multi-criteria decision making (FMCDM) technique for landfill suitability site evaluation. By using the fuzzy logic method (classification of suitable areas in the range of 0 to 1 scale), the superposing of the information layers related to drainage, soil, land use/land cover, slope, land use, and geology maps were performed in the study. Based on the result obtained in this study, five (5) potential sites are suitable for the construction of a landfill are proposed, two of which belong to the most suitable zone, and the existing waste disposal site belonged to the unsuitable zone.

Keywords: fuzzy logic multi-criteria decision making, geographic information system, landfill, suitable site, waste disposal

Procedia PDF Downloads 142
17529 Effect of Question Answer Relationship (QARs) in Science Reading on the Academic Achievement of Students in Biology

Authors: Helen Ngozi Ibe, Chimmuanya Ezere

Abstract:

The study investigated the effect of Question Answer Relationships (QARs) in science reading on secondary school students’ achievement in Biology in Owerri Education Zone II of Imo State. The study adopted a quasi-experimental design and was guided by two research questions and two hypotheses. The sample comprised of 67 SS2 Biology students. The sample was drawn using random sampling technique. One researcher made instrument titled: Biology Achievement Test (BAT) was used for collecting the data of the study. The reliability of the instrument was established using Kuder Richardson formula (KR-20) which yielded a reliability index of 0.85 and Cronbach alpha for the BSIRS with an index of 0.71. Research questions were answered using mean and standard deviation. T-test statistics was used to test the hypotheses at 0.05 level of significance. The major findings are that students exposed to QARs strategy in science reading had higher achievement mean scores in biology than students in the control group; there is no significant difference between the achievement mean scores of male and female students exposed to QARs. The researchers recommended that science teachers should teach students the Question Answer Relationship reading strategy and that science students should endeavour to use the question - answer relationship reading strategy in classroom and individual science reading in order to enhance high academic achievement in the subjects being read.

Keywords: academic achievement, biology, science reading, question-answer relationship

Procedia PDF Downloads 124
17528 Rebalancing Your Workforce Post-COVID - A Leadership Framework for Unlocking Performance and Strengthen Resilience

Authors: Thomas Seemann, Melanie Seemann

Abstract:

The work environment has changed considerably due to the COVID pandemic. A growing body of empirical research shows that employees feel increasingly stressed and anxious. They consider themselves more detached from the organization they work for than previously. Organizations need to readjust their leadership practices to cope with this situation and rebuild work motivation and resilience. We propose a leadership tool that focuses on two key dimensions, which we call the "task channel" and the "energy channel." Managing the task channel comprises balancing the challenge [C] of a task and the corresponding skill set [S] of the individual performing the task. Recent research findings shed light on how to balance these two factors and create optimal work conditions in the workplace. Managing the energy channel comprise balancing the workload [WL] of an employee and his/her capacity to work [CW]. This ensures that the mid-term and long-term effectiveness of employees is maintained and energy depletion, fatigue, and burn-out are prevented. Organizations can actively apply strategies to leverage wellsprings and effectively reenergize their workforce. Thinking through and acting upon these factors will provide leaders with the insights they need to maximize their people's performance and, at the same time, establish a more mindful workplace.

Keywords: resilience, motivation, employee engagement, leadership

Procedia PDF Downloads 131
17527 Boundary Layer Control Using a Magnetic Field: A Case Study in the Framework of Ferrohydrodynamics

Authors: C. F. Alegretti, F. R. Cunha, R. G. Gontijo

Abstract:

This work investigates the effects of an applied magnetic field on the geometry-driven boundary layer detachment flow of a ferrofluid over a sudden expansion. Both constitutive equation and global magnetization equation for a ferrofluid are considered. Therefore, the proposed formulation consists in a coupled magnetic-hydrodynamic problem. Computational simulations are carried out in order to explore, not only the viability to control flow instabilities, but also to evaluate the consistency of theoretical aspects. The unidirectional sudden expansion in a ferrofluid flow is investigated numerically under the perspective of Ferrohydrodynamics in a two-dimensional domain using a Finite Differences Method. The boundary layer detachment induced by the sudden expansion results in a recirculating zone, which has been extensively studied in non-magnetic hydrodynamic problems for a wide range of Reynolds numbers. Similar investigations can be found in literature regarding the sudden expansion under the magnetohydrodynamics framework, but none considering a colloidal suspension of magnetic particles out of the superparamagnetic regime. The vorticity-stream function formulation is implemented and results in a clear coupling between the flow vorticity and its magnetization field. Our simulations indicate a systematic decay on the length of the recirculation zone as increasing physical parameters of the flow, such as the intensity of the applied field and the volume fraction of particles. The results all are discussed from a physical point of view in terms of the dynamical non-dimensional parameters. We argue that the decrease/reduction in the recirculation region of the flow is a direct consequence of the magnetic torque balancing the action of the torque produced by viscous and inertial forces of the flow. For the limit of small Reynolds and magnetic Reynolds parameters, the diffusion of vorticity balances the diffusion of the magnetic torque on the flow. These mechanics control the growth of the recirculation region.

Keywords: boundary layer detachment, ferrofluid, ferrohydrodynamics, magnetization, sudden expansion

Procedia PDF Downloads 203
17526 Effects of the Compressive Eocene Tectonic Phase in the Bou Kornine-Ressas-Messella Structure and Surroundings (Northern Tunisia)

Authors: Aymen Arfaoui, Abdelkader Soumaya

Abstract:

The Messalla-Ressas-Bou Kornine (MRB) and Hammamet Korbous (HK) major trending North-South fault zones provide a good opportunity to show the effects of the Eocene compressive phase in northern Tunisia. They acted as paleogeographical boundaries during the Mesozoic and belonged to a significant strike-slip corridor called the «North-South Axis,» extending from the Saharan platform at the South to the Gulf of Tunis at the North. Our study area is situated in a relay zone between two significant strike-slip faults (HK and MRB), separating the Atlas domain from the Pelagian Block. We used a multidisciplinary approach, including fieldwork, stress inversion, and geophysical profiles, to argue the shortening event that affected the study region. The MRB and HK contractional duplex is a privileged area for a local stress field and stress nucleation. The stress inversion of fault slip data reveals an Eocene compression with NW-SE trending SHmax, reactivating most of the ancient Mesozoic normal faults in the region. This shortening phase is represented in the MRB belt by an angular unconformity between the Upper Eocene over various Cretaceous strata. The stress inversion data reveal a compressive tectonic with an average NW-SE trending Shmax. The major N-S faults are reactivated under this shortening as sinistral oblique faults. The orientation of SHmax deviates from NW-SE to E-W near the preexisting deep faults of MRB and HK. This E-W stress direction generated the emerging overlap of Ressas-Messella and blind thrust faults in the Cretaceous deposits. The connection of the sub-meridian reverse faults in depth creates "flower structures" under an E-W local compressive stress. In addition, we detected a reorientation of the SHmax into an N-S direction in the central part of the MRB - HK contractional duplex, creating E-W reverse faults and overlapping zones. Finally, the Eocene compression constituted the first major tectonic phase which inverted the Mesozoic preexisting extensive fault system in Northern Tunisia.

Keywords: Tunisia, eocene compression, tectonic stress field, Bou Kornine-Ressas-Messella

Procedia PDF Downloads 71
17525 Gas While Drilling (GWD) Classification in Betara Complex; An Effective Approachment to Optimize Future Candidate of Gumai Reservoir

Authors: I. Gusti Agung Aditya Surya Wibawa, Andri Syafriya, Beiruny Syam

Abstract:

Gumai Formation which acts as regional seal for Talang Akar Formation becomes one of the most prolific reservoir in South Sumatra Basin and the primary exploration target in this area. Marine conditions were eventually established during the continuation of transgression sequence leads an open marine facies deposition in Early Miocene. Marine clastic deposits where calcareous shales, claystone and siltstones interbedded with fine-grained calcareous and glauconitic sandstones are the domination of lithology which targeted as the hydrocarbon reservoir. All this time, the main objective of PetroChina’s exploration and production in Betara area is only from Lower Talang Akar Formation. Successful testing in some exploration wells which flowed gas & condensate from Gumai Formation, opened the opportunity to optimize new reservoir objective in Betara area. Limitation of conventional wireline logs data in Gumai interval is generating technical challenge in term of geological approach. A utilization of Gas While Drilling indicator initiated with the objective to determine the next Gumai reservoir candidate which capable to increase Jabung hydrocarbon discoveries. This paper describes how Gas While Drilling indicator is processed to generate potential and non-potential zone by cut-off analysis. Validation which performed by correlation and comparison with well logs, Drill Stem Test (DST), and Reservoir Performance Monitor (RPM) data succeed to observe Gumai reservoir in Betara Complex. After we integrated all of data, we are able to generate a Betara Complex potential map and overlaid with reservoir characterization distribution as a part of risk assessment in term of potential zone presence. Mud log utilization and geophysical data information successfully covered the geological challenges in this study.

Keywords: Gumai, gas while drilling, classification, reservoir, potential

Procedia PDF Downloads 355
17524 Evaluation of the Effects of Lead on Some Physiological and Hormonal Biomarkeurs among Workers

Authors: Mansouri Ouarda, Adbdennour Cherif, Boukarma Ziad

Abstract:

Environmental and biological monitoring are used for the evaluation of exposure to industrial chemicals, and provide a tool for assessing workers’ exposure to chemicals. The organs or tissues where the first biological effects can be observed with increasing amounts of lead toxicity. This study aims at evaluating the effect of the metal element-trace; lead, on the sex hormones in male workers, exposed to this metal on the level of the manufacturing plant of lead accumulators. The results indicate a significant reduction of the testosterone concentration in exposed workers compared to the control. However, the rate of LH was strongly increased at the individuals exposed to Pb. A significant difference concerning the rate of FSH, the hormone Prolactin and cortisol was recorded. The indicators of the lead poisoning indicate a very highly significant increase in the value of Pbs which vary between (142-796 µg/L) among which 50% of the workers present a high lead poisoning and the value of PPZ which vary between (43-554µg/L). The biochemical parameters show a significant increase in the rate of the créatinine, the urea and the acid urique. The hepatic results show no significant differentiation in the rate of TGO and TGP between both groups of study. However the rates of the enzyme phosphatase alkaline, triglyceride, and cholesterol a significant difference were registered.

Keywords: hormons, parameters, physilogical, Pbs, PPZ

Procedia PDF Downloads 377
17523 Investigation of the Growth Kinetics of Phases in Ni–Sn System

Authors: Varun A Baheti, Sanjay Kashyap, Kamanio Chattopadhyay, Praveen Kumar, Aloke Paul

Abstract:

Ni–Sn system finds applications in the microelectronics industry, especially with respect to flip–chip or direct chip, attach technology. Here the region of interest is under bump metallization (UBM), and solder bump (Sn) interface due to the formation of brittle intermetallic phases there. Understanding the growth of these phases at UBM/Sn interface is important, as in many cases it controls the electro–mechanical properties of the product. Cu and Ni are the commonly used UBM materials. Cu is used for good bonding because of fast reaction with solder and Ni often acts as a diffusion barrier layer due to its inherently slower reaction kinetics with Sn–based solders. Investigation on the growth kinetics of phases in Ni–Sn system is reported in this study. Just for simplicity, Sn being major solder constituent is chosen. Ni–Sn electroplated diffusion couples are prepared by electroplating pure Sn on Ni substrate. Bulk diffusion couples prepared by the conventional method are also studied along with Ni–Sn electroplated diffusion couples. Diffusion couples are annealed for 25–1000 h at 50–215°C to study the phase evolutions and growth kinetics of various phases. The interdiffusion zone was analysed using field emission gun equipped scanning electron microscope (FE–SEM) for imaging. Indexing of selected area diffraction (SAD) patterns obtained from transmission electron microscope (TEM) and composition measurements done in electron probe micro−analyser (FE–EPMA) confirms the presence of various product phases grown across the interdiffusion zone. Time-dependent experiments indicate diffusion controlled growth of the product phase. The estimated activation energy in the temperature range 125–215°C for parabolic growth constants (and hence integrated interdiffusion coefficients) of the Ni₃Sn₄ phase shed light on the growth mechanism of the phase; whether its grain boundary controlled or lattice controlled diffusion. The location of the Kirkendall marker plane indicates that the Ni₃Sn₄ phase grows mainly by diffusion of Sn in the binary Ni–Sn system.

Keywords: diffusion, equilibrium phase, metastable phase, the Ni-Sn system

Procedia PDF Downloads 307
17522 Protection Plan of Medium Voltage Distribution Network in Tunisia

Authors: S. Chebbi, A. Meddeb

Abstract:

The distribution networks are often exposed to harmful incidents which can halt the electricity supply of the customer. In this context, we studied a real case of a critical zone of the Tunisian network which is currently characterized by the dysfunction of its plan of protection. In this paper, we were interested in the harmonization of the protection plan settings in order to ensure a perfect selectivity and a better continuity of service on the whole of the network.

Keywords: distribution network Gabes-Tunisia, continuity of service, protection plan settings, selectivity

Procedia PDF Downloads 510
17521 The Dependence of Carbonate Pore Geometry on Fossils: Examples from Zechstein, Poland

Authors: Adam Fheed

Abstract:

Carbonate porosity can be deceptive in the aspect of hydrocarbon exploration due to pore geometry variations, which are to some extent controlled by fossils. Therefore, the main aim of this paper was to assess the dependence of pore geometry and reservoir quality on fossils. The Permian Zechstein Limestone (Ca1) carbonates from the Brońsko Reef, located on the Wolsztyn Ridge in West Poland, were examined. Seventy meters of drill cores were described along with well log examination and transmitted-light microscope research. The archival porosity-permeability data was utilized to calibrate the well logs and look for the potential petrophysical trends. Several organism assemblages were recognized in the reef. Its bottom was colonized by the branched bryozoans which were fragmented and dissolved leaving poorly connected molds. Subsequently, numerous bivalves and gastropods appeared and their shells were heavily dissolved to form huge, albeit poorly communicated caverns. Such pores were also typical for local brachiopod occurrences. Although the caverns were widespread, and probably linked to the meteoric dissolution or freshwater flushing, severe anhydrite cementation has destroyed the majority of pores. Close to the top of Ca1, near the center of the reef, the fossil-rich zone comprising fenestrate bryozoans, extremely abundant encrusting foraminifers, bivalves, brachiopods, gastropods and ostracods, was identified. The zone contained extremely frequent dissolution channels formed within former shells of foraminifers, which had previously encrusted the bryozoans. The deposition of Ca1 strata has ultimately terminated with a poorly porous and generally impermeable stromatolitic layer containing scarce fossils. In general, the permeability of the reef rocks studied turned out to be the highest under the presence of foraminifer-related channels. In such cases, it frequently approached 100 mD. The presence of channels and other pores gave the average effective porosity derived from shallow resistivity and helium porosimetry of around 16 and 18 %, respectively. The highest porosity (over 18 %), often co-occurring with relatively low permeability (chiefly below 20 mD) was noted for the bottommost zone of the reef, represented by branched bryozoans. This is probably owing to a large amount of unconnected bryozoan-related molds. It was concluded that fossils played a major role in porosity formation and controlled the pore geometry significantly. While the dissolution of bivalves and brachiopods resulted in cavernous porosity formation, numerous molds were typically related with the alteration of branched bryozoans, gastropods and ostracods. Importantly, the bendy dissolution channels after the encrusting foraminifers appeared to be decisive in improving reservoir quality – specifically when permeability is considered. Acknowledgment: The research was financed by the Polish National Science Centre’s project No. UMO-2016/23/N/ST10/00350.

Keywords: dissolution channels, fossils, Permian, porosity

Procedia PDF Downloads 85
17520 Agro-Morphological Traits Based Genetic Diversity Analysis of ‘Ethiopian Dinich’ Plectranthus edulis (Vatke) Agnew Populations Collected from Diverse Agro-Ecologies in Ethiopia

Authors: Fekadu Gadissa, Kassahun Tesfaye, Kifle Dagne, Mulatu Geleta

Abstract:

‘Ethiopian dinich’ also called ‘Ethiopian potato’ is one of the economically important ‘orphan’ edible tuber crops indigenous to Ethiopia. We evaluated the morphological and agronomic traits performances of 174 samples from Ethiopia at multiple locations using 12 qualitative and 16 quantitative traits, recorded at the correct growth stages. We observed several morphotypes and phenotypic variations for qualitative traits along with a wide range of mean performance values for all quantitative traits. Analysis of variance for each quantitative trait showed a highly significant (p<0.001) variation among the collections with eventually non-significant variation for environment-traits interaction for all but flower length. A comparatively high phenotypic and genotypic coefficient of variation was observed for plant height, days to flower initiation, days to 50% flowering and tuber number per hill. Moreover, the variability and coefficients of variation due to genotype-environment interaction was nearly zero for all the traits except flower length. High genotypic coefficients of variation coupled with a high estimate of broad sense heritability and high genetic advance as a percent of collection mean were obtained for tuber weight per hill, number of primary branches per plant, tuber number per hill and number of plants per hill. Association of tuber yield per hectare of land showed a large magnitude of positive phenotypic and genotypic correlation with those traits. Principal components analysis revealed 76% of the total variation for the first six principal axes with high factor loadings again from tuber number per hill, number of primary branches per plant and tuber weight. The collections were grouped into four clusters with the weak region (zone) of origin based pattern. In general, there is high genetic-based variability for ‘Ethiopian dinich’ improvement and conservation. DNA based markers are recommended for further genetic diversity estimation for use in breeding and conservation.

Keywords: agro-morphological traits, Ethiopian dinich, genetic diversity, variance components

Procedia PDF Downloads 190
17519 Experiences of Being a Manager in the Municipal Sector in Rural Northern Sweden

Authors: S. Asplund, J. Åhlin, S. Åström, B. M. Lindgren

Abstract:

The aim of this qualitative study was to describe experiences of work-related stress among highly stressed municipal employees in rural northern Sweden. We interviewed 15 employees in the municipal sector in rural northern Sweden using a semi-structured guide and subjected the interviews to qualitative content analysis. Under the main theme of Suffering Though Endless Chaos, we summarized four themes: facing incompatible interests and high demands due to lack of time and resources; feeling powerless, trapped, and ignored due to lack of control; feeling insufficient, insecure, and guilty due to challenging relations and high expectations; and struggling with consequences such as health problems, spillover effects on family life, and difficulty coping. Findings from this study suggest the importance of acknowledging suffering among municipal employees in a stressful work environment. An imbalance between job demands and resources is affecting both the health and family lives of employees and also their ability to work. It seems important to improve the work environment through supportive leadership, job control, and reasonable job demands to prevent stress, reduce suffering, and create a healthy organization.

Keywords: manager, municipal sector, occupational health, qualitative content analysis

Procedia PDF Downloads 84
17518 Insights into Kinematics and Basin Development through Palinspastic Reconstructions in Pull-Apart Basin Sunda Strait: Implication for the Opportunity of Hydrocarbon Exploration in Fore-Arc Basin, Western Indonesia

Authors: Alfathony Krisnabudhi, Syahli Reza Ananda, M. Edo Marshal, M. Maaruf Mukti

Abstract:

This study investigates the kinematics and basin development of pull-apart basin Sunda Strait based on palinspastic reconstructions of new acquired seismic reflection data to unravel hydrocarbon exploration opportunity in frontier area, fore-arc basin western Indonesia. We use more than 780 km seismic reflection data that cover whole basin. Structural patterns in Sunda Strait are dominated by northwest-southeast trending planar and listric-normal faults which appear to be graben and half-graben system. The main depocentre of this basin is East Semangko graben and West Semangko graben that are formed by overstepping of Sumatra Fault Zone and Ujungkulon Fault Zone. In father east, another depocentre is recognized as the Krakatau graben. The kinematic evolution started in Middle Miocene, characterized by the initiation of basement faulting with 0% to 7.00% extension. Deposition stratigraphic unit 1 and unit 2 started at 7.00% to 10.00% extension in Late Miocene and recognized as pre-transtensional deposit. The Plio-Pleistocene unit 3 and 4 were deposited as syn-transtensional deposit with 10.00% to 17.00% extension contemporaneously with the initiation of uplift NW-SE trending ridges due to the evolution of cross-basin fault in central basin and the development of en-echelon basin margin in a transtensional system. The control of sedimentation rate and basin subsidence cause the Neogene sediment to be very thick. We suggest that both controls allow thermal and pressure to generate hydrocarbon habitats in the pre-transtensional deposits. It is reinforced by stable kinematic evolution and interpretation of the deposition environment of pre-transtensional deposits that are deposited in the marine environment.

Keywords: kinematics, palinspastic, Sunda Strait, hydrocarbon exploration, fore-arc basin

Procedia PDF Downloads 182
17517 Combination of Lamotrigine and Duloxetine: A Potential Approach for the Treatment of Acute Bipolar Depression

Authors: Kedar S. Prabhavalkar, Nimmy Baby Poovanpallil

Abstract:

Lamotrigine is approved for maintenance treatment of bipolar I disorder. However, its role in the treatment of acute bipolar depression is not well clear. Its efficacy in the treatment of major depressive disorders including refractory unipolar depression suggested the use of lamotrigine as an augmentation drug for acute bipolar depression. The present study aims to evaluate and perform a comparative analysis of the therapeutic effects of lamotrigine, an epileptic mood stabilizer, when used alone and in combination with duloxetine in treating acute bipolar depression at different doses of lamotrigine. Male swiss albino mice were used. For evaluation of efficacy of combination, immobility period was analyzed 30 min after the treatment from forced swim and tail suspension tests. Further amount of sucrose consumed in sucrose preference test was estimated. The combination of duloxetine and lamotrigine showed potentiation of antidepressant activity in acute models. Decrease in immobility time and increase in the amount of sucrose consumption in stressed mice were higher in combined group compared to lamotrigine monotherapy group. Brain monoamine levels were also attenuated more with combination compared to monotherapy. Results of the present study suggest potential role of lamotrigine and duloxetine combination in the treatment of acute bipolar depression.

Keywords: lamotrigine, duloxetine, acute bipolar depression, augmentation

Procedia PDF Downloads 507
17516 Revealing the Potential of Geotourism and Geoheritage of Gedangsari Area, Yogyakarta

Authors: Cecilia Jatu, Adventino

Abstract:

Gedangsari is located in Gunungkidul, Yogyakarta Province, which has several criteria to be used as a new geosite object. The research area is located in the southern mountain zone of Java, composed of 5 rock formations with Oligocene up to Middle Miocene age. The purpose of this study is to reveal the potential of geotourism and the geoheritage to be proposed as a new geosite and to make a geosite map of Gedangsari. The research method used is descriptive data collection and which includes quantitative geological data collection, geotourism, and heritage sites, then supported by petrographic analysis, geological structure, geological mapping, and SWOT analysis. The geological data proved that Gedangsari consists of igneous rock (intrusion), pyroclastic rock, and sediment rock. This condition caused many varieties and particular geomorphological platform. Geotourism that include in Gedangsari are Luweng Sampang Canyon, Gedangsari Bouma Sequence, Watugajah Columnar Joint, Gedangsari Marine Fan Sediment, and Tegalrejo Waterfall. There is also Tegalrejo Village, which can be considered as geoheritage site because of its culture and batik traditional cloth. The results of the SWOT analysis, Gedangsari geosite must be developed and appropriately promoted in order to improve the existence. The development of geosite area will have a significant impact that improve the economic growth of the surrounding community and can be used by the government as base information for sustainable development. In addition, the making of an educational map about the geological conditions and geotourism location of the Gedangsari geosite can increase the people's knowledge about Gedangsari.

Keywords: Gedangsari, geoheritage, geotourism, geosite

Procedia PDF Downloads 122
17515 Mental Health Diagnosis through Machine Learning Approaches

Authors: Md Rafiqul Islam, Ashir Ahmed, Anwaar Ulhaq, Abu Raihan M. Kamal, Yuan Miao, Hua Wang

Abstract:

Mental health of people is equally important as of their physical health. Mental health and well-being are influenced not only by individual attributes but also by the social circumstances in which people find themselves and the environment in which they live. Like physical health, there is a number of internal and external factors such as biological, social and occupational factors that could influence the mental health of people. People living in poverty, suffering from chronic health conditions, minority groups, and those who exposed to/or displaced by war or conflict are generally more likely to develop mental health conditions. However, to authors’ best knowledge, there is dearth of knowledge on the impact of workplace (especially the highly stressed IT/Tech workplace) on the mental health of its workers. This study attempts to examine the factors influencing the mental health of tech workers. A publicly available dataset containing more than 65,000 cells and 100 attributes is examined for this purpose. Number of machine learning techniques such as ‘Decision Tree’, ‘K nearest neighbor’ ‘Support Vector Machine’ and ‘Ensemble’, are then applied to the selected dataset to draw the findings. It is anticipated that the analysis reported in this study would contribute in presenting useful insights on the attributes contributing in the mental health of tech workers using relevant machine learning techniques.

Keywords: mental disorder, diagnosis, occupational stress, IT workplace

Procedia PDF Downloads 288
17514 Working within the Zone of Proximal Development: Does It Help for Reading Strategy?

Authors: Mahmood Dehqan, Peyman Peyvasteh

Abstract:

In recent years there has been a growing interest in issues concerning the impact of sociocultural theory (SCT) of learning on different aspects of second/foreign language learning. This study aimed to find the possible effects of sociocultural teaching techniques on reading strategy of EFL learners. Indeed, the present research compared the impact of peer and teacher scaffolding on EFL learners’ reading strategy use across two proficiency levels. To this end, a pre-test post-test quasi-experimental research design was used and two instruments were utilized to collect the data: Nelson English language test and reading strategy questionnaire. Ninety five university students participated in this study were divided into two groups of teacher and peer scaffolding. Teacher scaffolding group received scaffolded help from the teacher based on three mechanisms of effective help within ZPD: graduated, contingent, dialogic. In contrast, learners of peer scaffolding group were unleashed from the teacher-fronted classroom as they were asked to carry out the reading comprehension tasks with the feedback they provided for each other. Results obtained from ANOVA revealed that teacher scaffolding group outperformed the peer scaffolding group in terms of reading strategy use. It means teacher’s scaffolded help provided within the learners’ ZPD led to better reading strategy improvement compared with the peer scaffolded help. However, the interaction effect between proficiency factor and teaching technique was non-significant, leading to the conclusion that strategy use of the learners was not affected by their proficiency level in either teacher or peer scaffolding groups.

Keywords: peer scaffolding, proficiency level, reading strategy, sociocultural theory, teacher scaffolding

Procedia PDF Downloads 381
17513 A Strategy to Oil Production Placement Zones Based on Maximum Closeness

Authors: Waldir Roque, Gustavo Oliveira, Moises Santos, Tatiana Simoes

Abstract:

Increasing the oil recovery factor of an oil reservoir has been a concern of the oil industry. Usually, the production placement zones are defined after some analysis of geological and petrophysical parameters, being the rock porosity, permeability and oil saturation of fundamental importance. In this context, the determination of hydraulic flow units (HFUs) renders an important step in the process of reservoir characterization since it may provide specific regions in the reservoir with similar petrophysical and fluid flow properties and, in particular, techniques supporting the placement of production zones that favour the tracing of directional wells. A HFU is defined as a representative volume of a total reservoir rock in which petrophysical and fluid flow properties are internally consistent and predictably distinct of other reservoir rocks. Technically, a HFU is characterized as a rock region that exhibit flow zone indicator (FZI) points lying on a straight line of the unit slope. The goal of this paper is to provide a trustful indication for oil production placement zones for the best-fit HFUs. The FZI cloud of points can be obtained from the reservoir quality index (RQI), a function of effective porosity and permeability. Considering log and core data the HFUs are identified and using the discrete rock type (DRT) classification, a set of connected cell clusters can be found and by means a graph centrality metric, the maximum closeness (MaxC) cell is obtained for each cluster. Considering the MaxC cells as production zones, an extensive analysis, based on several oil recovery factor and oil cumulative production simulations were done for the SPE Model 2 and the UNISIM-I-D synthetic fields, where the later was build up from public data available from the actual Namorado Field, Campos Basin, in Brazil. The results have shown that the MaxC is actually technically feasible and very reliable as high performance production placement zones.

Keywords: hydraulic flow unit, maximum closeness centrality, oil production simulation, production placement zone

Procedia PDF Downloads 329