Search results for: lower-body negative pressure
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 8326

Search results for: lower-body negative pressure

2026 Oxide Based Memristor and Its Potential Application in Analog-Digital Electronics

Authors: P. Michael Preetam Raj, Souri Banerjee, Souvik Kundu

Abstract:

Oxide based memristors were fabricated in order to establish its potential applications in analog/digital electronics. BaTiO₃-BiFeO₃ (BT-BFO) was employed as an active material, whereas platinum (Pt) and Nb-doped SrTiO₃ (Nb:STO) were served as a top and bottom electrodes, respectively. Piezoelectric force microscopy (PFM) was utilized to present the ferroelectricity and repeatable polarization inversion in the BT-BFO, demonstrating its effectiveness for resistive switching. The fabricated memristors exhibited excellent electrical characteristics, such as hysteresis current-voltage (I-V), high on/off ratio, high retention time, cyclic endurance, and low operating voltages. The band-alignment between the active material BT-BFO and the substrate Nb:STO was experimentally investigated using X-Ray photoelectron spectroscopy, and it attributed to staggered heterojunction alignment. An energy band diagram was proposed in order to understand the electrical transport in BT-BFO/Nb:STO heterojunction. It was identified that the I-V curves of these memristors have several discontinuities. Curve fitting technique was utilized to analyse the I-V characteristic, and the obtained I-V equations were found to be parabolic. Utilizing this analysis, a non-linear BT-BFO memristors equivalent circuit model was developed. Interestingly, the obtained equivalent circuit of the BT-BFO memristors mimics the identical electrical performance, those obtained in the fabricated devices. Based on the developed equivalent circuit, a finite state machine (FSM) design was proposed. Efforts were devoted to fabricate the same FSM, and the results were well matched with those in the simulated FSM devices. Its multilevel noise filtering and immunity to external noise characteristics were also studied. Further, the feature of variable negative resistance was established by controlling the current through the memristor.

Keywords: band alignment, finite state machine, polarization inversion, resistive switching

Procedia PDF Downloads 122
2025 Effect of Helical Flow on Separation Delay in the Aortic Arch for Different Mechanical Heart Valve Prostheses by Time-Resolved Particle Image Velocimetry

Authors: Qianhui Li, Christoph H. Bruecker

Abstract:

Atherosclerotic plaques are typically found where flow separation and variations of shear stress occur. Although helical flow patterns and flow separations have been recorded in the aorta, their relation has not been clearly clarified and especially in the condition of artificial heart valve prostheses. Therefore, an experimental study is performed to investigate the hemodynamic performance of different mechanical heart valves (MHVs), i.e. the SJM Regent bileaflet mechanical heart valve (BMHV) and the Lapeyre-Triflo FURTIVA trileaflet mechanical heart valve (TMHV), in a transparent model of the human aorta under a physiological pulsatile right-hand helical flow condition. A typical systolic flow profile is applied in the pulse-duplicator to generate a physiological pulsatile flow which thereafter flows past an axial turbine blade structure to imitate the right-hand helical flow induced in the left ventricle. High-speed particle image velocimetry (PIV) measurements are used to map the flow evolution. A circular open orifice nozzle inserted in the valve plane as the reference configuration initially replaces the valve under investigation to understand the hemodynamic effects of the entered helical flow structure on the flow evolution in the aortic arch. Flow field analysis of the open orifice nozzle configuration illuminates the helical flow effectively delays the flow separation at the inner radius wall of the aortic arch. The comparison of the flow evolution for different MHVs shows that the BMHV works like a flow straightener which re-configures the helical flow pattern into three parallel jets (two side-orifice jets and the central orifice jet) while the TMHV preserves the helical flow structure and therefore prevent the flow separation at the inner radius wall of the aortic arch. Therefore the TMHV is of better hemodynamic performance and reduces the pressure loss.

Keywords: flow separation, helical aortic flow, mechanical heart valve, particle image velocimetry

Procedia PDF Downloads 161
2024 Diagnosis of the Hydrological and Hydrogeological Potential in the Mancomojan Basin for Estimations of Offer and Demand

Authors: J. M. Alzate, J. Baena

Abstract:

This work presents the final results of the ‘Diagnosis of the hydrological and hydrogeological potential in the Mancomojan basin for estimations of offer and demand’ with the purpose of obtaining solutions of domestic supply for the communities of the zone of study. There was realized the projection of population of the paths by three different scenes. The highest water total demand appears with the considerations of the scene 3, with a total demand for the year 2050 of 59.275 m3/year (1,88 l/s), being the path San Francisco the one that exercises a major pressure on the resource with a demand for the same year of the order of 31.189 m3/year (0,99 l/s). As for the hydrogeological potential of the zone and as alternative of supply of the studied communities, the stratigraphic columns obtained of the geophysical polls do not show strata saturated with water that could be considered to be a potential source of supply for the communities. The water registered in the geophysics tests presents very low resistances what indicates that he presents ions, this water meets in the rock interstices very thin granulometries which indicates that it is a water of constitution, and the flow of this one towards more permeable granulometries is void or limited. The underground resource that is registered so much in electrical vertical polls (SEV) as in tomography and that is saturating rocks of thin granulometry (clays and slimes), was demonstrated by content of ions, which is consistent with the abundant presence of plaster and the genesis marinades with transition to continental of the geological units in the zone. Predominant rocks are sedimentary, sandy rocks of grain I die principally, in minor proportion were observed also sandstones of thick grain to conglomerate with clastic rock of quartz, chert and siltstone of the Formation Mess and sandstones (of thin, average and thick grain) alternating with caps conglomerate whose thickness is, in general, between 5 and 15 cm, the nodules of sandstones are frequent with the same composition of the sandstones that contain them, in some cases with calcareous and crossed stratification of the formation Sincelejo Miembro Morroa.

Keywords: hydrological, hydrogeological potential, geotomography, vertical electrical sounding (VES)

Procedia PDF Downloads 247
2023 The New Far-Right: The Social Construction of Hatred against the Contemporary Islamic Community in Multicultural Australia

Authors: Angel Adams

Abstract:

In Australia, the contemporary social construction of hatred against the Islamic community was facilitated through the mainstream media. Australian public figures who have depicted Muslims and Islam not only as potential terrorists but also as incompatible with the country’s values and identities have helped to increase the level of fear against the Islamic community, leading sympathetic far-right movements to shift discussions towards anti-Islamic and anti-Muslim rhetoric. Political opportunities combined with a socially constructed narrative of fear of the ‘other’, introduced during the White Australia Policy of 1901, has allowed extreme and radical far-right movements to justify hate against the contemporary Australian Islamic community. This study aims to answer the following question: How does Australia’s founding provide a fertile environment to the spread of hatred against the contemporary Islamic community? The paper demonstrates that a forged social construct of grievances concerning the Islamic community in Australia has led to a surge in supply of far-right activism to combat what has become a perceived ‘national threat’. In essence, Australia’s history of a fear of the ‘other’ brings challenges to a multicultural society, and can potentially lead to a more unstable socio-political environment where abuse and violence are normalized and more likely to develop. Furthermore, the paper aims to bring a more nuanced understanding of what is considered ‘new far-right’ discourses with shared anti-Islam and anti-Muslim agendas in Australia. The political opportunity structures theory was the mechanism used to determine how new forms of far-right groups have become more mainstream in Australia. Previous studies on far-right groups in Australia have relied on qualitative data, but further empirical research in this area is sorely needed. Above all, this paper clarifies how hatred against minorities can have a negative impact on wider communities and allow a global narrative of ‘us’ versus ‘them’ to erupt from the fringes of society in Australia.

Keywords: Australia, Islamophobia, far-right, nationalism, political opportunity structures, political violence, social construction

Procedia PDF Downloads 119
2022 The Psychological Impact of War Trauma on Refugees

Authors: Anastasia Papachristou, Anastasia Ntikoudi, Vasileios Saridakis

Abstract:

The safety and health care needs of refugees have become an increasingly important issue all over the world especially during last few decades. Wars are the primary reason for refugees to leave their countries. Moreover, refugees are frequently exposed to a variety of stressors such as socioeconomic disadvantages, poverty, changes in family structure and functioning, losing social support, difficulty to access education, living in very crowded places, experiencing racism and isolation. This systematic review included research studies published between 2007-2017 from the search databases Medline, Scopus, Cinahl and PubMed, with keywords 'war survivors', 'war trauma', 'psychiatric disorders', 'refugees'. In order to meet the purpose of the systematic review, further research for complementary studies was conducted into the literature references of the research articles included in this study that would meet the criteria. Overall, 14 studies were reviewed and evaluated. The majority of them demonstrated that the most common psychiatric disorders observed among war refugees are post-traumatic stress disorder (PTSD), depression, anxiety and multiple somatic complaints. Moreover, significant relationship was shown between the number of traumatic events experienced by the refugees and sociodemographic features such as gender, age and previous family history of any psychological disorder. War violence is highly traumatic, causing multiple, long-term negative outcomes such as the aforementioned psychiatric disorders. The number of the studies reviewed in this systematic review is not representative of the problem and its significance. The need for care of the survivors and their families is vital. Further research is necessary in order to clarify the role of predictive factors in the development and maintenance of post-traumatic stress and the rest psychiatric disorders following war trauma. In conclusion, it is necessary to have large multicenter studies in the future in order to be able to draw reliable conclusions about the effects of war.

Keywords: psychiatric disorders, refugees, war survivors, war trauma

Procedia PDF Downloads 181
2021 Analysis of the Occurrence of Hydraulic Fracture Phenomena in Roudbar Lorestan Dam

Authors: Masoud Ghaemi, MohammadJafar Hedayati, Faezeh Yousefzadeh, Hoseinali Heydarzadeh

Abstract:

According to the statistics of the International Committee on Large Dams, internal erosion and piping (scour) are major causes of the destruction of earth-fill dams. If such dams are constructed in narrow valleys, the valley walls will increase the arching of the dam body due to the transfer of vertical and horizontal stresses, so the occurrence of hydraulic fracturing in these embankments is more likely. Roudbar Dam in Lorestan is a clay-core pebble earth-fill dam constructed in a relatively narrow valley in western Iran. Three years after the onset of impoundment, there has been a fall in dam behavior. Evaluation of the dam behavior based on the data recorded on the instruments installed inside the dam body and foundation confirms the occurrence of internal erosion in the lower and adjacent parts of the core on the left support (abutment). The phenomenon of hydraulic fracturing is one of the main causes of the onset of internal erosion in this dam. Accordingly, the main objective of this paper is to evaluate the validity of this hypothesis. To evaluate the validity of this hypothesis, the dam behavior during construction and impoundment has been first simulated with a three-dimensional numerical model. Then, using validated empirical equations, the safety factor of the occurrence of hydraulic fracturing phenomenon upstream of the dam score was calculated. Then, using the artificial neural network, the failure time of the given section was predicted based on the maximum stress trend created. The study results show that steep slopes of valley walls, sudden changes in coefficient, and differences in compressibility properties of dam body materials have caused considerable stress transfer from core to adjacent valley walls, especially at its lower levels. This has resulted in the coefficient of confidence of the occurrence of hydraulic fracturing in each of these areas being close to one in each of the empirical equations used.

Keywords: arching, artificial neural network, FLAC3D, hydraulic fracturing, internal erosion, pore water pressure

Procedia PDF Downloads 164
2020 NDVI as a Measure of Change in Forest Biomass

Authors: Amritansh Agarwal, Tejaswi Agarwal

Abstract:

Forest ecosystem plays very important role in the global carbon cycle. It stores about 80% of all above ground and 40% of all below ground terrestrial organic carbon. There is much interest in the extent of tropical forests and their rates of deforestation for two reasons: greenhouse gas contributions and the impact of profoundly negative biodiversity. Deforestation has many ecological, social and economic consequences, one of which is the loss of biological diversity. The rapid deployment of remote sensing (RS) satellites and development of RS analysis techniques in the past three decades have provided a reliable, effective, and practical way to characterize terrestrial ecosystem properties. Global estimates of tropical deforestation vary widely and range from 50,000 to 170,000 km2 /yr Recent FAO tropical deforestation estimates for 1990–1995 cite 116,756km2 / yr globally. Remote Sensing can prove to be a very useful tool in monitoring of forests and associated deforestation to a sufficient level of accuracy without the need of physically surveying the forest areas as many of them are physically inaccessible. The methodology for the assessment of forest cover using digital image processing (ERDAS) has been followed. The satellite data for the study was procured from USGS website in the digital format. While procuring the satellite data, care was taken to ensure that the data was cloud and aerosol free by making using of FLAASH atmospheric correction technique. The Normalized Difference Vegetation Index (NDVI) has been used as a numerical indicator of the reduction in ground biomass. NDVI = (near I.R - Red)/ (near I.R + Red). After calculating the NDVI variations and associated mean we have analysed the change in ground biomass. Through this paper we have tried to indicate the rate of deforestation over a given period of time by comparing the forest cover at different time intervals. With the help of remote sensing and GIS techniques it is clearly shows that the total forest cover is continuously degrading and transforming into various land use/land cover category.

Keywords: remote sensing, deforestation, supervised classification, NDVI change detection

Procedia PDF Downloads 381
2019 Identification and Classification of Medicinal Plants of Indian Himalayan Region Using Hyperspectral Remote Sensing and Machine Learning Techniques

Authors: Kishor Chandra Kandpal, Amit Kumar

Abstract:

The Indian Himalaya region harbours approximately 1748 plants of medicinal importance, and as per International Union for Conservation of Nature (IUCN), the 112 plant species among these are threatened and endangered. To ease the pressure on these plants, the government of India is encouraging its in-situ cultivation. The Saussurea costus, Valeriana jatamansi, and Picrorhiza kurroa have also been prioritized for large scale cultivation owing to their market demand, conservation value and medicinal properties. These species are found from 1000 m to 4000 m elevation ranges in the Indian Himalaya. Identification of these plants in the field requires taxonomic skills, which is one of the major bottleneck in the conservation and management of these plants. In recent years, Hyperspectral remote sensing techniques have been precisely used for the discrimination of plant species with the help of their unique spectral signatures. In this background, a spectral library of the above 03 medicinal plants was prepared by collecting the spectral data using a handheld spectroradiometer (325 to 1075 nm) from farmer’s fields of Himachal Pradesh and Uttarakhand states of Indian Himalaya. The Random forest (RF) model was implied on the spectral data for the classification of the medicinal plants. The 80:20 standard split ratio was followed for training and validation of the RF model, which resulted in training accuracy of 84.39 % (kappa coefficient = 0.72) and testing accuracy of 85.29 % (kappa coefficient = 0.77). This RF classifier has identified green (555 to 598 nm), red (605 nm), and near-infrared (725 to 840 nm) wavelength regions suitable for the discrimination of these species. The findings of this study have provided a technique for rapid and onsite identification of the above medicinal plants in the field. This will also be a key input for the classification of hyperspectral remote sensing images for mapping of these species in farmer’s field on a regional scale. This is a pioneer study in the Indian Himalaya region for medicinal plants in which the applicability of hyperspectral remote sensing has been explored.

Keywords: himalaya, hyperspectral remote sensing, machine learning; medicinal plants, random forests

Procedia PDF Downloads 191
2018 Research on Low interfacial Tension Viscoelastic Fluid Oil Displacement System in Unconventional Reservoir

Authors: Long Long Chen, Xinwei Liao, Shanfa Tang, Shaojing Jiang, Ruijia Tang, Rui Wang, Shu Yun Feng, Si Yao Wang

Abstract:

Unconventional oil reservoirs have the characteristics of strong heterogeneity and poor injectability, and traditional chemical flooding technology is not effective in such reservoirs; polymer flooding in the production of heavy oil reservoirs is difficult to handle produced fluid and easy to block oil wells, etc. Therefore, a viscoelastic fluid flooding system with good adaptability, low interfacial tension, plugging, and diverting capabilities was studied. The viscosity, viscoelasticity, surface/interfacial activity, wettability, emulsification, and oil displacement performance of the anionic Gemini surfactant flooding system were studied, and the adaptability of the system to the reservoir environment was evaluated. The oil displacement effect of the system in low-permeability and high-permeability (heavy oil) reservoirs was investigated, and the mechanism of the system to enhance water flooding recovery was discussed. The results show that the system has temperature resistance and viscosity increasing performance (65℃, 4.12mPa•s), shear resistance and viscoelasticity; at a lower concentration (0.5%), the oil-water interfacial tension can be reduced to ultra-low (10-3mN/m); has good emulsifying ability for heavy oil, and is easy to break demulsification (4.5min); has good adaptability to reservoirs with high salinity (30000mg/L). Oil flooding experiments show that this system can increase the water flooding recovery rate of low-permeability homogeneous and heterogeneous cores by 13% and 15%, respectively, and can increase the water-flooding recovery rate of high-permeability heavy oil reservoirs by 40%. The anionic Gemini surfactant flooding system studied in this paper is a viscoelastic fluid, has good emulsifying and oil washing ability, can effectively improve sweep efficiency, reduce injection pressure, and has broad application in unconventional reservoirs to enhance oil recovery prospect.

Keywords: oil displacement system, recovery factor, rheology, interfacial activity, environmental adaptability

Procedia PDF Downloads 111
2017 Early and Mid-Term Results of Anesthetic Management of Minimal Invasive Coronary Artery Bypass Grafting Using One Lung Ventilation

Authors: Devendra Gupta, S. P. Ambesh, P. K Singh

Abstract:

Introduction: Minimally invasive coronary artery bypass grafting (MICABG) is a less invasive method of performing surgical revascularization. Minimally invasive direct coronary artery bypass (MIDCAB) provides many anesthetic challenges including one lung ventilation (OLV), managing myocardial ischemia, and pain. We present an early and midterm result of the use of this technique with OLV. Method: We enrolled 62 patients for analysis operated between 2008 and 2012. Patients were anesthetized and left endobronchial tube was placed. During the procedure left lung was isolated and one lung ventilation was maintained through right lung. Operation was performed utilizing off pump technique of coronary artery bypass grafting through a minimal invasive incision. Left internal mammary artery graft was done for single vessel disease and radial artery was utilized for other grafts if required. Postoperative ventilation was done with single lumen endotracheal tube. Median follow-up is 2.5 years (6 months to 4 years). Results: Median age was 58.5 years (41-77) and all were male. Single vessel disease was present in 36, double vessel in 24 and triple vessel disease in 2 patients. All the patients had normal left ventricular size and function. In 2 cases difficulty were encounter in placement of endobronchial tube. In 1 case cuff of endobronchial tube was ruptured during intubation. High airway pressure was developed on OLV in 1 case and surgery was accomplished with two lung anesthesia with low tidal volume. Mean postoperative ventilation time was 14.4 hour (11-22). There was no perioperative and 30 day mortality. Conversion to median sternotomy to complete the operation was done in 3.23% (2 out of 62 patients). One patient had acute myocardial infarction postoperatively and there were no deaths during follow-up. Conclusion: MICABG is a safe and effective method of revascularization with OLV in low risk candidates for coronary artery bypass grafting.

Keywords: MIDCABG, one lung ventilation, coronary artery bypass grafting, endobronchial tube

Procedia PDF Downloads 411
2016 Green Synthesis and Characterization of Zinc Oxide Nanoparticles Using Neem (Azadirachta Indica) Leaf Extract and Investigation of Its Antibacterial Activities

Authors: Emineh Tsegahun Gedif

Abstract:

Zinc oxide nanoparticles (ZnO NPs) have garnered significant attention due to their diverse applications encompassing catalytic, optical, photonic, and antibacterial properties. In this study, we successfully synthesized zinc oxide nanoparticles using a rapid, environmentally benign, and cost-effective method. Neem (Azadirachta indica) leaf extract served as the reducing agent for Zn (NO₃)₂.6H2O solution under optimized conditions (pH = 9). Qualitative screening techniques and FT-IR Spectroscopy confirmed the presence of active biomolecules such as flavonoids, phenolic groups, alkaloids, terpenoids, and tannins within the Neem leaf extract, both before and after reduction. The formation of ZnO NPs was visually evident through a distinct color change from colorless to light yellow. The biosynthesized nanoparticles underwent comprehensive characterization through UV-visible, FT-IR, and XRD spectroscopies. The reduction process proved to be straightforward and user-friendly, with UV-visible spectroscopy demonstrating a surface plasmon resonance (SPR) at 321 nm, unequivocally confirming the ZnO NP formation. X-ray diffraction analysis elucidated the crystal structure, revealing an average particle size of approximately 20 nm using Scherrer's equation based on the line width of the plane. Furthermore, the synthesized zinc oxide nanoparticles were evaluated for their antimicrobial properties against both Gram-positive and Gram-negative bacteria. The results showcased significant inhibitory activity, with the highest zone of inhibition observed against Escherichia coli (15 mm) and comparatively lower activity against Staphylococcus aureus. This research underscores the potential of Neem leaf extract-mediated synthesis of ZnO NPs as an eco-friendly and effective approach for various applications, including antibacterial agents.

Keywords: zinc oxide nanoparticles (ZnO NPs), bioreducing agent, green synthesis, antibacterial activity

Procedia PDF Downloads 51
2015 Forest Policy and Its Implications on Private Forestry Development: A Case Study in Rautahat District, Nepal

Authors: Dammar Bahadur Adhikari

Abstract:

Community forestry in Nepal has got disproportionately high level of support from government and other actors in forestry sector. Even though master plan for forestry sector (1989) has highlighted community and private forestry as one component, the government policies and other intervention deliberately left out private forestry in its structure and programs. The study aimed at providing the pathway for formulating appropriate policies to address need of different kind of forest management regimes in Rautahat district, Nepal. The key areas the research focused were assessment of current status of private forestry, community forest users' understanding on private forestry; criteria for choosing species of private forestry and factors affecting establishment of private forestry in the area. Qualitative and quantitative data were collected employing questionnaire survey, rapid forest assessment and key informant interview. The study found out that forest policies are imposed due to intense pressure of exogenous forces than due to endogenous demand. Most of the local people opine that their traditional knowledge and skills are not sufficient for private forestry and hence need training on the matter. Likewise, local use, market value and rotation dictate the choice of species for plantation in private forests. Currently district forest office is the only government institution working in the area of private forestry all other governmental and non-governmental organizations have condoned. private forestry. Similarly, only permanent settlers in the area are found to establish private forests other forest users such as migrants and forest encroachers follow opportunistic behavior to meet their forest product need from community and national forests. In this regard, the study recommends taking appropriate step to support other forest management system including private forestry provide community forestry the benefits of competition as suggested by Darwin in 18th century, one and half century back and to help alleviate poverty by channelizing benefits to household level.

Keywords: community forest, forest management, poverty, private forest, users’ group

Procedia PDF Downloads 326
2014 Influence of the Moisture Content on the Flowability of Fine-Grained Iron Ore Concentrate

Authors: C. Lanzerstorfer, M. Hinterberger

Abstract:

The iron content of the ore used is crucial for the productivity and coke consumption rate in blast furnace pig iron production. Therefore, most iron ore deposits are processed in beneficiation plants to increase the iron content and remove impurities. In several comminution stages, the particle size of the ore is reduced to ensure that the iron oxides are physically liberated from the gangue. Subsequently, physical separation processes are applied to concentrate the iron ore. The fine-grained ore concentrates produced need to be transported, stored, and processed. For smooth operation of these processes, the flow properties of the material are crucial. The flowability of powders depends on several properties of the material: grain size, grain size distribution, grain shape, and moisture content of the material. The flowability of powders can be measured using ring shear testers. In this study, the influence of the moisture content on the flowability for the Krivoy Rog magnetite iron ore concentrate was investigated. Dry iron ore concentrate was mixed with varying amounts of water to produce samples with a moisture content in the range of 0.2 to 12.2%. The flowability of the samples was investigated using a Schulze ring shear tester. At all measured values of the normal stress (1.0 kPa – 20 kPa), the flowability decreased significantly from dry ore to a moisture content of approximately 3-5%. At higher moisture contents, the flowability was nearly constant, while at the maximum moisture content the flowability improved for high values of the normal stress only. The results also showed an improving flowability with increasing consolidation stress for all moisture content levels investigated. The wall friction angle of the dust with carbon steel (S235JR), and an ultra-high molecule low-pressure polyethylene (Robalon) was also investigated. The wall friction angle increased significantly from dry ore to a moisture content of approximately 3%. For higher moisture content levels, the wall friction angles were nearly constant. Generally, the wall friction angle was approximately 4° lower at the higher wall normal stress.

Keywords: iron ore concentrate, flowability, moisture content, wall friction angle

Procedia PDF Downloads 303
2013 Buy-and-Hold versus Alternative Strategies: A Comparison of Market-Timing Techniques

Authors: Jonathan J. Burson

Abstract:

With the rise of virtually costless, mobile-based trading platforms, stock market trading activity has increased significantly over the past decade, particularly for the millennial generation. This increased stock market attention, combined with the recent market turmoil due to the economic upset caused by COVID-19, make the topics of market-timing and forecasting particularly relevant. While the overall stock market saw an unprecedented, historically-long bull market from March 2009 to February 2020, the end of that bull market reignited a search by investors for a way to reduce risk and increase return. Similar searches for outperformance occurred in the early, and late 2000’s as the Dotcom bubble burst and the Great Recession led to years of negative returns for mean-variance, index investors. Extensive research has been conducted on fundamental analysis, technical analysis, macroeconomic indicators, microeconomic indicators, and other techniques—all using different methodologies and investment periods—in pursuit of higher returns with lower risk. The enormous variety of timeframes, data, and methodologies used by the diverse forecasting methods makes it difficult to compare the outcome of each method directly to other methods. This paper establishes a process to evaluate the market-timing methods in an apples-to-apples manner based on simplicity, performance, and feasibility. Preliminary findings show that certain technical analysis models provide a higher return with lower risk when compared to the buy-and-hold method and to other market-timing strategies. Furthermore, technical analysis models tend to be easier for individual investors both in terms of acquiring the data and in analyzing it, making technical analysis-based market-timing methods the preferred choice for retail investors.

Keywords: buy-and-hold, forecast, market-timing, probit, technical analysis

Procedia PDF Downloads 85
2012 Structural and Functional Characterization of the Transcriptional Regulator Rv1176 of Mycobacterium tuberculosis H37Rv

Authors: Vikash Yadav, Ashish Arora

Abstract:

Microorganisms have self-defense mechanisms to protect themselves from toxic environments. Phenolic acid decarboxylase(pad) is responsible for the defense against toxicity caused by phenolic acids, converting them into less toxic vinyl derivatives. The transcription of the pad gene is regulated by a negative transcription factor, phenolic acid decarboxylase regulators (PadR), in a substrate-inducible manner. The PadR family members share the conserved DNA-binding features and interact with the operator DNA using a winged helix-turn-helix (wHTH) motif, which contains a three-helix motif and a β-stranded wing. The members of this family function as transcriptional regulators that are involved in various cellular survival processes, such as toxin production, detoxification, multidrug resistance, antibiotic biosynthesis, and carbon catabolism. Rv1176 of Mycobacterium tuberculosis H37Rv has been assigned to the PadR family protein that remains to be structurally and functionally uncharacterized. To reveal the structural mechanism by which Rv1176 could regulates effector-responsive transcription, several experiments were performed, including Electrophoretic Mobility Shift Assay (EMSA) for DNA protein interaction, differential scanning calorimetry (DSC) and Differential Scanning Fluorimetry (DSF) for temperature and ligand-dependent protein stability, Circular Dichroism (CD) spectroscopy for secondary structure analysis. Further, to evaluate the functional role of Rv1176, the intracellular survival of recombinant M. smegmatis was examined in murine macrophage cell line J774A.1 and different stressed conditions like oxidative, pH, and nutritive stress. All these studies demonstrated that Rv1176 could behave as a transcription regulator and its expression in recombinant M. smegmatis increases intracellular survival.

Keywords: EMSA, Mycobacterium tuberculosis, PadR family protein, transcriptional regulator

Procedia PDF Downloads 62
2011 LTF Expression Profiling Which is Essential for Cancer Cell Proliferation and Metastasis, Correlating with Clinical Features, as Well as Early Stages of Breast Cancer

Authors: Azar Heidarizadi, Mahdieh Salimi, Hossein Mozdarani

Abstract:

Introduction: As a complex disease, breast cancer results from several genetic and epigenetic changes. Lactoferrin, a member of the transferrin family, is reported to have a number of biological functions, including DNA synthesis, immune responses, iron transport, etc., any of which could play a role in tumor progression. The aim of this study was to investigate the bioinformatics data and experimental assay to find the pattern of promoter methylation and gene expression of LTF in breast cancer in order to study its potential role in cancer management. Material and Methods: In order to evaluate the methylation status of the LTF promoter, we studied the MS-PCR and Real-Time PCR on samples from patients with breast cancer and normal cases. 67 patient samples were conducted for this study, including tumoral, plasma, and normal tissue adjacent samples, as well as 30 plasma from normal cases and 10 tissue breast reduction cases. Subsequently, bioinformatics analyses such as cBioPortal databases, string, and genomatix were conducted to disclose the prognostic value of LTF in breast cancer progression. Results: The analysis of LTF expression showed an inverse relationship between the expression level of LTF and the stages of tissues of breast cancer patients (p<0.01). In fact, stages 1 and 2 had a high expression in LTF, while, in stages 3 and 4, a significant reduction was observable (p < 0.0001). LTF expression frequently alters with a decrease in the expression in ER⁺, PR⁺, and HER2⁺ patients (P < 0.01) and an increase in the expression in the TNBC, LN¯, ER¯, and PR- patients (P < 0.001). Also, LTF expression is significantly associated with metastasis and lymph node involvement factors (P < 0.0001). The sensitivity and specificity of LTF were detected, respectively. A negative correlation was detected between the results of level expression and methylation of the LTF promoter. Conclusions: The altered expression of LTF observed in breast cancer patients could be considered as a promotion in cell proliferation and metastasis even in the early stages of cancer.

Keywords: LTF, expression, methylation, breast cancer

Procedia PDF Downloads 42
2010 Child Labor and Injury Occurrence in Nicaragua: A Gender Perspective Analysis

Authors: Cristina Domínguez, Steven N. Cuadra

Abstract:

Aims: The aims of this study are: 1) to describe the occurrence and estimate the risk of suffering injuries of any kind, especially work-related injuries, in rural children working in agricultural activities and in urban children working on the street 2) to explore factors that might be associated with the occurrence of work-related injuries among child workers such as gender, school attendance, and performance of household chore. Method: We performed a crossectional study among working children in agricultural activities (120) and on the street (108) and in non-working referents (140) in 2019. We investigated self-reported injuries during the last 12 months, with focus on work-related injuries. Incidence rate, rate ratios, and 95% CI were calculated by Poisson regression. Results: Agricultural workers have a higher incidence of work-related injuries (2.1 per 1000 person-days) than children working on the street (1.8 per 1000 person-days). However, when considering girl’s unpaid work at home, girls had higher occurrence. Girls had a 30% increase on the risk of suffering work related injuries compared to boys. Performing household chore and attending school were the major predictors of injury occurrence. Discussion: Our data suggest If such partial and full-time girl’s housework is taken into account, there would be little or no variation between the sexes with regard to injuries occurrence, and the incidence rate of work related injuries among girls could even exceed that of boys A greater understanding of the interaction of factors related to how child workers spend their time, and its impact on children’s health, is needed in order to identify feasible and appropriate strategies to reduce the negative effect of work on children when elimination of child labor is not reachable in the short term. Clearly, gender aspects on child labor may allow for more effective targeting of prevention efforts.

Keywords: injuries, child labor, agricultural work, gender

Procedia PDF Downloads 114
2009 Correlations among Their Characteristics and Determination of Some Morphological Characteristics of Perennial Ryegrass Genotypes

Authors: Abdullah Özköse, Ahmet Tamkoç

Abstract:

This study aimed to determine some plant characteristics of perennial ryegrass (Lolium perenne L.) genotypes collected from the natural flora of Ankara and correlations between these characteristics. In order to evaluate for breeding purposes according to Turkey's environmental conditions, perennial ryegrass plants collected from natural pasture of Ankara at 2004 were utilized. The collected seeds of plants were sown in pots and seedlings were prepared in greenhouse. Seedlings were transplanted to the experimental field at 50x50 cm intervals in Randomized Complete Blocks Design in 2005. Data were obtained from the observations and measurements of 568 perennial ryegrasses in 2007 and 2008. Perennial ryegrass plants’ in the spring re-growth time, color, density, growth habit, tendency to inflorescences, time of inflorescence, plant height, length of upper internode, spike length, leaf length, leaf width, leaf area, leaf shape, number of spikelets per spike, seed yield per spike, and 1000 grain weight were investigated and correlation analyses were made on the data. Correlation coefficients were estimated between all paired combinations of the traits. The yield components exhibited varying trends of association among themselves. Seed yield per spike showed significant and positive association with number of spikelets per spike, 1000 grain weight, plant height, length of upper internode, spike length, leaf length, leaf width, leaf area and color, but significant and negative association with growth habit and in the spring re-growth time spring.

Keywords: correlation, morphological traits, Lolium perenne

Procedia PDF Downloads 441
2008 Mother as Troubles Teller: A Discourse Analytic Case Study of Mother-Adolescent Daughter Interaction

Authors: Domenica L. DelPrete

Abstract:

Viewed as a type of rapport-talk, troubles telling is a common conversational practice among female friends who wish to establish connection, show empathy, or share a disconcerting experience. This study shows how troubles talk between a mother and her adolescent daughter has a different interactional outcome. Specifically, it reveals how discursive interaction with an adolescent daughter becomes increasingly volatile when the mother steps out of the role of nurturer and into the role of troubles teller. Naturally occurring interactions between a mother and her 15-year-old daughter were videotaped in their family home over a two-week period. The data were primarily analyzed from an interactional sociolinguistic perspective, using conversation analytic techniques for transcriptions and discursive analysis. The following questions guided this research: (1) How are troubles telling discursively accomplished in the everyday talk of a mother and her adolescent daughter? and (2) What topic prompts the mother to engage in troubles talk? The data show that the mother engages her daughter in troubles to talk on issues related to body image and physical appearance and does so by (1) repeated questioning, (2) not accepting the daughter’s response as adequate, and (3) proffering self-deprecation. Findings reveal that engaging an adolescent daughter in a conversational practice reserved for female friendship groups creates a negative connection and relational disharmony. Since 'telling one’s troubles' assumes an egalitarian relationship between individuals, mother’s trouble telling creates a peer-like interaction that the adolescent daughter repeatedly resists. This study also proposes a discursive consciousness raising, which hopes to enhance communication between mothers and daughters by revealing the signals that show an adolescent daughter’s unwillingness to participate in troubles talk. Being in tune to these cues may prompt mothers to hesitate before pursuing a topic that will not garner the positive interactional outcome they seek.

Keywords: discursive interaction, maternal roles, mother-daughter interaction, troubles telling

Procedia PDF Downloads 115
2007 Antibacterial Studies on Cellulolytic Bacteria for Termite Control

Authors: Essam A. Makky, Chan Cai Wen, Muna Jalal, Mashitah M. Yusoff

Abstract:

Termites are considered as important pests that could cause severe wood damage and economic losses in urban, agriculture and forest of Malaysia. The ability of termites to degrade cellulose depends on association of gut cellulolytic microflora or better known as mutual symbionts. With the idea of disrupting the mutual symbiotic association, better pest control practices can be attained. This study is aimed to isolate cellulolytic bacteria from the gut of termites and carry out antibacterial studies for the termite. Confirmation of cellulase activity is done by qualitative and quantitative methods. Impacts of antibiotics and their combinations, as well as heavy metals and disinfectants, are conducted by using disc diffusion method. Effective antibacterial agents are then subjected for termite treatment to study the effectiveness of the agents as termiticides. 24 cellulolytic bacteria are isolated, purified and screened from the gut of termites. All isolates were identified as Gram-negative with either rod or cocci in shape. For antibacterial studies result, isolates were found to be 100% sensitive to 4 antibiotics (rifampicin, tetracycline, gentamycin, and neomycin), 2 heavy metals (cadmium and mercury) and 3 disinfectants (lactic acid, formalin, and hydrogen peroxide). 22 out of 36 antibiotic combinations showed synergistic effect while 15 antibiotic combinations showed an antagonistic effect on isolates. The 2 heavy metals and 3 disinfectants that showed 100% effectiveness, as well as 22 antibiotic combinations, that showed synergistic effect were used for termite control. Among the 27 selected antibacterial agents, 12 of them were found to be effective to kill all the termites within 1 to 6 days. Mercury, lactic acid, formalin and hydrogen peroxide were found to be the most effective termiticides in which all termites were killed within 1 day only. These effective antibacterial agents possess a great potential to be a new application to control the termite pest species in the future.

Keywords: antibacterial, cellulase, termicide, termites

Procedia PDF Downloads 456
2006 Hierarchical Manganese and Nickel Selenide based Ultra-efficient Electrode Material for All-Solid-State Asymmetric Supercapacitors with Extended Energy Efficacy

Authors: Siddhant Srivastav, Soumyaranjan Mishra, Sumanta Kumar Meher

Abstract:

Researchers are attempting to develop extremely efficient electrochemical energy storage technologies as a result of the phenomenal advancement of portable electronic devices. Because of their improved electrical conductivity and narrower band gap, transition metal selenide-based nanostructures have piqued the interest of many researchers in this field. Based on this concept, we present a simple anion exchange hydrothermal synthesis method for synthesizing manganese and nickel based selenide (Mn/NiSe2) nanostructure for use in all-solid-state asymmetric supercapacitors. According to the comprehensive physicochemical characterizations, the material has lowly crystalline properties, a distinct porous microstructure, and a significant bonding contact between the metal and the selenium. The electrochemical investigations of the Mn/NiSe2 electrode material revealed supercapacitive charge discharge properties, excellent electro-kinetic reversibility, and minimal charge transfer resistance (Rct). Furthermore, the all-solid-state asymmetric supercapacitor device assembled using Mn/NiSe2 as positive electrode, nitrogen doped reduced graphene oxide (N-rGO) as negative electrode, and PVA-KOH gel as electrolyte/separator exhibit good redox behaviour, excellent charge-discharge properties with negligible voltage (IR) drop, and lower impedance characteristics. The solid state asymmetric supercapacitor device (Mn/NiSe2||N-rGO) demonstrated the power density of ultra-capacitors and the energy density of rechargeable batteries. Conclusively, the Mn/NiSe2 has been proposed as a potential outstanding electrode material for the next generation of all-solid-state asymmetric supercapacitors.

Keywords: anion exchange, asymmetric supercapacitor, supercapacitive charge-discharge, voltage drop

Procedia PDF Downloads 84
2005 Simulation of Concrete Wall Subjected to Airblast by Developing an Elastoplastic Spring Model in Modelica Modelling Language

Authors: Leo Laine, Morgan Johansson

Abstract:

To meet the civilizations future needs for safe living and low environmental footprint, the engineers designing the complex systems of tomorrow will need efficient ways to model and optimize these systems for their intended purpose. For example, a civil defence shelter and its subsystem components needs to withstand, e.g. airblast and ground shock from decided design level explosion which detonates with a certain distance from the structure. In addition, the complex civil defence shelter needs to have functioning air filter systems to protect from toxic gases and provide clean air, clean water, heat, and electricity needs to also be available through shock and vibration safe fixtures and connections. Similar complex building systems can be found in any concentrated living or office area. In this paper, the authors use a multidomain modelling language called Modelica to model a concrete wall as a single degree of freedom (SDOF) system with elastoplastic properties with the implemented option of plastic hardening. The elastoplastic model was developed and implemented in the open source tool OpenModelica. The simulation model was tested on the case with a transient equivalent reflected pressure time history representing an airblast from 100 kg TNT detonating 15 meters from the wall. The concrete wall is approximately regarded as a concrete strip of 1.0 m width. This load represents a realistic threat on any building in a city like area. The OpenModelica model results were compared with an Excel implementation of a SDOF model with an elastic-plastic spring using simple fixed timestep central difference solver. The structural displacement results agreed very well with each other when it comes to plastic displacement magnitude, elastic oscillation displacement, and response times.

Keywords: airblast from explosives, elastoplastic spring model, Modelica modelling language, SDOF, structural response of concrete structure

Procedia PDF Downloads 116
2004 Time to Pancreatic Surgery after Preoperative Biliary Drainage in Periampullary Cancers: A Systematic Review and Meta‑Analysis

Authors: Maatouk Mohamed, Nouira Mariem, Hamdi Kbir Gh, Mahjoubi M. F., Ben Moussa M.

Abstract:

Background and aim: Preoperative biliary drainage (PBD) has been introduced to lower bilirubin levels and to control the negative effects of obstructive jaundice in patients with malignant obstructive jaundice undergoing pancreaticoduodenectomy (PD). The optimal time interval between PBD and PD is still not clear. Delaying surgery by 4 to 6 weeks is the commonly accepted practice. However, delayed PD has been shown to decrease the rate of resection and adversely affect the tumor grading and prognosis. Thus, the purpose of our systematic review and meta-analysis was to evaluate the optimal period for PBD prior to PD: short or prolonged in terms of postoperative morbidity and survival outcomes. Methods: Trials were searched in PubMed, Science Direct, Google Scholar, and Cochrane Library until November 2022. Studies using PBD in patients with malignant obstructive jaundice that compared short duration group (SDG) (surgery performed within 3-4 weeks) with prolonged duration group (PDG) (at least 3-4 weeks after PBD) were included in this study. The risk of bias was assessed using the Rob v2 and Robins-I tools. The priori protocol was published in PROSPERO (ID: CRD42022381405). Results: Seven studies comprising 1625 patients (SDG 870, PDG 882) were included. All studies were non-randomized, and only one was prospective. No significant differences were observed between the SDG and PDG in mortality (OR= 0.59; 95% CI [0.30, 1.17], p=0.13), major morbidity (Chi² = 30.28, p <0.00001; I² = 87%), pancreatic fistula (Chi² = 6.61, p = 0.25); I² = 24%), post pancreatectomy haemorrhage (OR= 1.16; 95% CI [0.67, 2.01], p=0.59), positive drainage culture (OR= 0.36; 95% CI [0.10, 1.32], p=0.12), septic complications (OR= 0.78; 95% CI [0.23, 2.72], p=0.70), wound infection (OR= 0.08, p=0.07), operative time (MD= 0.21; p=0.21). Conclusion: Early surgery within 3 or 4 weeks after biliary drainage is both safe and effective. Thus, it is reasonable to suggest early surgery following PBD for patients having resectable periampullary cancers.

Keywords: preoperative biliary drainage, pancreatic cancer, pancreatic surgery, complication

Procedia PDF Downloads 55
2003 Assessment of Groundwater Chemistry and Quality Characteristics in an Alluvial Aquifer and a Single Plane Fractured-Rock Aquifer in Bloemfontein, South Africa

Authors: Modreck Gomo

Abstract:

The evolution of groundwater chemistry and its quality is largely controlled by hydrogeochemical processes and their understanding is therefore important for groundwater quality assessments and protection of the water resources. A study was conducted in Bloemfontein town of South Africa to assess and compare the groundwater chemistry and quality characteristics in an alluvial aquifer and single-plane fractured-rock aquifers. 9 groundwater samples were collected from monitoring boreholes drilled into the two aquifer systems during a once-off sampling exercise. Samples were collected through low-flow purging technique and analysed for major ions and trace elements. In order to describe the hydrochemical facies and identify dominant hydrogeochemical processes, the groundwater chemistry data are interpreted using stiff diagrams and principal component analysis (PCA), as complimentary tools. The fitness of the groundwater quality for domestic and irrigation uses is also assessed. Results show that the alluvial aquifer is characterised by a Na-HCO3 hydrochemical facie while fractured-rock aquifer has a Ca-HCO3 facie. The groundwater in both aquifers originally evolved from the dissolution of calcite rocks that are common on land surface environments. However the groundwater in the alluvial aquifer further goes through another evolution as driven by cation exchange process in which Na in the sediments exchanges with Ca2+ in the Ca-HCO3 hydrochemical type to result in the Na-HCO3 hydrochemical type. Despite the difference in the hydrogeochemical processes between the alluvial aquifer and single-plane fractured-rock aquifer, this did not influence the groundwater quality. The groundwater in the two aquifers is very hard as influenced by the elevated magnesium and calcium ions that evolve from dissolution of carbonate minerals which typically occurs in surface environments. Based on total dissolved levels (600-900 mg/L), groundwater quality of the two aquifer systems is classified to be of fair quality. The negative potential impacts of the groundwater quality for domestic uses are highlighted.

Keywords: alluvial aquifer, fractured-rock aquifer, groundwater quality, hydrogeochemical processes

Procedia PDF Downloads 183
2002 FEM Simulation of Tool Wear and Edge Radius Effects on Residual Stress in High Speed Machining of Inconel718

Authors: Yang Liu, Mathias Agmell, Aylin Ahadi, Jan-Eric Stahl, Jinming Zhou

Abstract:

Tool wear and tool geometry have significant effects on the residual stresses in the component produced by high-speed machining. In this paper, Coupled Eulerian and Lagrangian (CEL) model is adopted to investigate the residual stress in high-speed machining of Inconel718 with a CBN170 cutting tool. The result shows that the mesh with the smallest size of 5 um yields cutting forces and chip morphology in close agreement with the experimental data. The analysis of thermal loading and mechanical loading are performed to study the effect of segmented chip morphology on the machined surface topography and residual stress distribution. The effects of cutting edge radius and flank wear on residual stresses formation and distribution on the workpiece were also investigated. It is found that the temperature within 100um depth of the machined surface increases drastically due to the more friction heat generation with the contact area of tool and workpiece increasing when a larger edge radius and flank wear are used. With the depth further increasing, the temperature drops rapidly for all cases due to the low conductivity of Inconel718. Consequently, higher and deeper tensile residual stress is generated on the superficial. Furthermore, an increased depth of plastic deformation and compressive residual stress is noticed in the subsurface, which is attributed to the reduction of the yield strength under the thermal effect. Besides, the ploughing effect produced by a larger tool edge radius contributes more than flank wear. The magnitude variation of the compressive residual stress caused by various edge radius and flank wear have a totally opposite trend, which depends on the magnitude of the ploughing and friction pressure acting on the machined surface.

Keywords: Coupled Eulerian Lagrangian, segmented chip, residual stress, tool wear, edge radius, Inconel718

Procedia PDF Downloads 134
2001 Prevalence and Associated Factors of Overweight and Obesity in Children with Intellectual Disability: A Cross-Sectional Study among Chinese Children

Authors: Jing-Jing Wang, Yang Gao, Heather H. M. Kwok, Wendy Y. J. Huang

Abstract:

Objectives: Intellectual disability (ID) ranks among the top 20 most costly disorders. A child with ID creates a wide set of challenges to the individual, family, and society, and overweight and obesity aggravate those challenges. People with ID have the right to attain optimal health like the rest of the population. They should be given priority to eliminate existing health inequities. Childhood obesity epidemic and associated factors among children, in general, has been well documented, while knowledge about overweight and obesity in children with ID is scarce. Methods: A cross-sectional study was conducted among 524 Chinese children with ID (males: 68.9%, mean age: 12.2 years) in Hong Kong in 2015. Children’s height and weight were measured at school. Parents, in the presence of their children, completed a self-administered questionnaire at home about the children’s physical activity (PA), eating habits, and sleep duration in a typical week as well as parenting practices regarding children’s eating and PA, and their socio-demographic characteristics. Multivariate logistic regression estimated the potential risk factors for children being overweight. Results: The prevalence of overweight and obesity in children with ID was 31.3%, which was higher than their general counterparts (18.7%-19.9%). Multivariate analyses revealed that the risk factors of overweight and obese in children with ID included: comorbidity with autism, the maternal side being overweight or obese, parenting practices with less pressure to eat more, children having shorter sleep duration, longer periods of sedentary behavior, and higher intake frequencies of sweetened food, fried food, and meats, fish, and eggs. Children born in other places, having snacks more frequently, and having irregular meals were also more likely to be overweight or obese, with marginal significance. Conclusions: Children with ID are more vulnerable to being overweight or obese than their typically developing counterparts. Identified risk factors in this study highlight a multifaceted approach to the involvement of parents as well as the modification of some children’s questionable behaviors to help them achieve a healthy weight.

Keywords: prevalence, risk factors, obesity, children with disability

Procedia PDF Downloads 120
2000 Exploring the Relationships between Cyberbullying Perceptions and Facebook Attitudes of Turkish Students

Authors: Yavuz Erdoğan, Hidayet Çiftçi

Abstract:

Cyberbullying, a phenomenon among adolescents, is defined as actions that use information and communication technologies such as social media to support deliberate, repeated, and hostile behaviour by an individual or group. With the advancement in communication and information technology, cyberbullying has expanded its boundaries among students in schools. Thus, parents, psychologists, educators, and lawmakers must become aware of the potential risks of this phenomenon. In the light of these perspectives, this study aims to investigate the relationships between cyberbullying perception and Facebook attitudes of Turkish students. A survey method was used for the study and the data were collected by “Cyberbullying Perception Scale”, “Facebook Attitude Scale” and “Personal Information Form”. For this purpose, study has been conducted during 2014-2015 academic year, with a total of 748 students with 493 male (%65.9) and 255 female (%34.1) from randomly selected high schools. In the analysis of data Pearson correlation and multiple regression analysis, multivariate analysis of variance (MANOVA) and Scheffe post hoc test has been used. At the end of the study, the results displayed a negative correlation between Turkish students’ Facebook attitudes and cyberbullying perception (r=-.210; p<0.05). In order to identify the predictors of students’ cyberbullying perception, multiple regression analysis was used. As a result, significant relations were detected between cyberbullying perception and independent variables (F=5.102; p<0.05). Independent variables together explain 11.0% of the total variance in cyberbullying scores. The variables that significantly predict the students’ cyberbullying perception are Facebook attitudes (t=-5.875; p<0.05), and gender (t=3.035; p<0.05). In order to calculate the effects of independent variables on students’ Facebook attitudes and cyberbullying perception MANOVA was conducted. The results of the MANOVA indicate that the Facebook attitudes and cyberbullying perception were significantly differed according to students’ gender, age, educational attainment of the mother, educational attainment of the father, income of the family and daily usage of internet.

Keywords: facebook, cyberbullying, attitude, internet usage

Procedia PDF Downloads 391
1999 The Role of Trust in Intention to Use Prescribed and Non-prescribed Connected Devices

Authors: Jean-michel Sahut, Lubica Hikkerova, Wissal Ben Arfi

Abstract:

The Internet of Things (IoT) emerged over the last few decades in many fields. Healthcare can significantly benefit from IoT. This study aims to examine factors influencing the adoption of IoT in eHealth. To do so, an innovative framework has been developed which applies both the Technology Acceptance Model (TAM) and the United Theory of Acceptance and Use of Technology (UTAUT) model and builds on them by analyzing trust and perceived-risk dimensions to predict intention to use IoT in eHealth. In terms of methodology, a Partial Least Approach Structural Equation Modelling was carried out on a sample of 267 French users. The findings of this research support the significant positive effect of constructs set out in the TAM (perceived ease of use) on predicting behavioral intention by adding the effects identified for UTAUT variables. This research also demonstrates how perceived risk and trust are significant factors for models examining behavioral intentions to use IoT. Perceived risk enhanced by the trust has a significant effect on patients’ behavioral intentions. Moreover, the results highlight the key role of prescription as a moderator of IoT adoption in eHealth. Depending on whether an individual has a prescription to use connected devices or not, ease of use has a stronger impact on adoption, while trust has a negative impact on adoption for users without a prescription. In accordance with the empirical results, several practical implications can be proposed. All connected devices applied in a medical context should be divided into groups according to their functionality: whether they are essential for the patient’s health and whether they require a prescription or not. Devices used with a prescription are easily accepted because the intention to use them is moderated by the medical trust (discussed above). For users without a prescription, ease of use is a more significant factor than for users who have a prescription. This suggests that currently, connected e-Health devices and online healthcare systems have to take this factor into account to better meet the needs and expectations of end-users.

Keywords: internet of things, Healthcare, trust, consumer acceptance

Procedia PDF Downloads 130
1998 Quality of Life among Female Sex Workers of Selected Organization of Pokhara: A Methodological Triangulation

Authors: Sharmila Dahal Paudel

Abstract:

Background: There are around twenty-four thousand to twenty-eight thousand Female Sex Workers in Nepal. FSWs are the vulnerable groups for sexually transmitted infections (STIs) and human immunodeficiency virus (HIV) infections which directly and indirectly ease to reduce the quality of life of such groups. Due to their highly marginalized status, FSWs in Nepal have limited access to information about reproductive health and safe sex practices. The objectives of the study are to assess the quality of life of female sex workers and the factors affecting them. Materials and Methods: A descriptive cross-sectional study with methodological triangulation was conducted among 108 FSWs on the basis of service record of selected organization of Pokhara valley. The complete enumerative sampling was used to select FSWs. Structured interview schedule, WHOQOL-BREF and in-depth questionnaire were used to collect the data. The descriptive and inferential statistics were used to interpret the result. Results: The mean age of participants were 23.44 years and the mean quality of life score was 174.06 ranging from 56.54 to 370.78. Among the domain scores, the mean score is highest in social domain (55.89) followed by physical (45.42), psychological (39.27) and the environmental (34.23). Regarding the association of QOL with socio-demographic, occupation and health-related variables, the multi-linear regression suggests that the satisfaction with occupation was highly significant with the total QOL score (B=-50.50, SE=10.46; p= <0.001) and there is negative relation between QOL and feeling of exploitation and facing STI problems. This means those who feels exploited have significantly less QOL comparing with those who did not feel the same. In correlation analysis, all the domains are positively co-related with each domain which is found to be significant at 1% level of significance. Conclusion: The highest mean score was in social domain, and the lowest is in environmental domain which suggests that the items included in environmental domains could not be utilized or hindrance were there.

Keywords: FSWs, HIV, QOL, WHOQOL-BREF

Procedia PDF Downloads 159
1997 Development of an Experimental Model of Diabetes Co-Existing with Metabolic Syndrome in Rats

Authors: Rajesh Kumar Suman, Ipseeta Ray Mohanty, Manjusha K. Borde, Ujjawala maheswari, Y. A. Deshmukh

Abstract:

Background: Metabolic syndrome encompasses cluster of risk factors for cardiovascular disease which includes abdominal obesity, dyslipidemia, hypertension, and hyperglycemia. The incidence of metabolic syndrome is on the rise globally. Objective: The present study was designed to develop a unique animal model that will mimic the pathological features seen in a large pool of individuals with diabetes and metabolic syndrome; suitable for pharmacological screening of drugs beneficial in this condition. Material and Methods: A combination of high fat diet (HFD) and low dose of streptozotocin (STZ) at 30, 35 and 40 mg/kg was used to induce metabolic syndrome co-existing with diabetes mellitus in Wistar rats. Results: The 40 mg/kg STZ produced sustained hyperglycemia and the dose was thus selected for our study to induce diabetes mellitus. Rat fed HFD (HF-DC) group showed significant (p < 0.001) increase in body weight on 4th and 7th week as compared with NC (Normal Control) group rats. However, the increase in body weight of HF-DC group rats was not sustained at the end of 10th weeks. Various components of metabolic syndrome such as dyslipidemia {(Increased Triglyceride, total Cholesterol, LDL Cholesterol and decreased HDL Cholesterol)}, diabetes mellitus (Blood Glucose, HbA1c, Serum Insulin, C-peptide), hypertension {Systolic Blood pressure (p < 0.001)} were mimicked in the developed model of metabolic syndrome co existing with diabetes mellitus. In addition significant cardiac injury as indicated by CPK-MB levels, artherogenic index, hs-CRP. The decline in hepatic function {(p < 0.01) increase in the level of SGPT (U/L)} and renal function {(increase in creatinine levels (p < 0.01)} when compared to NC group rats. The histopathological assessment confirmed presence of edema, necrosis and inflammation in Heart, Pancreas, Liver and Kidney of HFD-DC group as compared to NC. Conclusion: The present study has developed a unique rodent model of metabolic syndrome; with diabetes as an essential component.

Keywords: diabetes, metabolic syndrome, high fat diet, streptozotocin, rats

Procedia PDF Downloads 334