Search results for: methods for inverse problems
Commenced in January 2007
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Paper Count: 20024

Search results for: methods for inverse problems

6584 Experimental and Computational Investigations on the Mitigation of Air Pollutants Using Pulsed Radio Waves

Authors: Gangadhara Siva Naga Venkata Krishna Satya Narayana Swamy Undi

Abstract:

Particulate matter (PM) pollution in ambient air is a major environmental health risk factor contributing to disease and mortality worldwide. Current air pollution control methods have limitations in reducing real-world ambient PM levels. This study demonstrates the efficacy of using pulsed radio wave technology as a distinct approach to lower outdoor particulate pollution. Experimental data were compared with computational models to evaluate the efficiency of pulsed waves in coagulating and settling PM. Results showed 50%+ reductions in PM2.5 and PM10 concentrations at the city scale, with particle removal rates exceeding gravity settling by over 3X. Historical air quality data further validated the significant PM reductions achieved in test cases. Computational analyses revealed the underlying coagulation mechanisms induced by the pulsed waves, supporting the feasibility of this strategy for ambient particulate control. The pulsed electromagnetic technology displayed robustness in sustainably managing PM levels across diverse urban and industrial environments. Findings highlight the promise of this advanced approach as a next-generation solution to mitigate particulate air pollution and associated health burdens globally. The technology's scalability and energy efficiency can help address a key gap in current efforts to improve ambient air quality.

Keywords: particulate matter, mitigation technologies, clean air, ambient air pollution

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6583 Cycle-Oriented Building Components and Constructions Made from Paper Materials

Authors: Rebecca Bach, Evgenia Kanli, Nihat Kiziltoprak, Linda Hildebrand, Ulrich Knaack, Jens Schneider

Abstract:

The building industry has a high demand for resources and at the same time is responsible for a significant amount of waste created worldwide. Today's building components need to contribute to the protection of natural resources without creating waste. This is defined in the product development phase and impacts the product’s degree of being cycle-oriented. Paper-based materials show advantage due to their renewable origin and their ability to incorporate different functions. Besides the ecological aspects like renewable origin and recyclability the main advantages of paper materials are its light-weight but stiff structure, the optimized production processes and good insulation values. The main deficits from building technology’s perspective are the material's vulnerability to humidity and water as well as inflammability. On material level, those problems can be solved by coatings or through material modification. On construction level intelligent setup and layering of a building component can improve and also solve these issues. The target of the present work is to provide an overview of developed building components and construction typologies mainly made from paper materials. The research is structured in four parts: (1) functions and requirements, (2) preselection of paper-based materials, (3) development of building components and (4) evaluation. As part of the research methodology at first the needs of the building sector are analyzed with the aim to define the main areas of application and consequently the requirements. Various paper materials are tested in order to identify to what extent the requirements are satisfied and determine potential optimizations or modifications, also in combination with other construction materials. By making use of the material’s potentials and solving the deficits on material and on construction level, building components and construction typologies are developed. The evaluation and the calculation of the structural mechanics and structural principals will show that different construction typologies can be derived. Profiles like paper tubes can be used at best for skeleton constructions. Massive structures on the other hand can be formed by plate-shaped elements like solid board or honeycomb. For insulation purposes corrugated cardboard or cellulose flakes have the best properties, while layered solid board can be applied to prevent inner condensation. Enhancing these properties by material combinations for instance with mineral coatings functional constructions mainly out of paper materials were developed. In summary paper materials offer a huge variety of possible applications in the building sector. By these studies a general base of knowledge about how to build with paper was developed and is to be reinforced by further research.

Keywords: construction typologies, cycle-oriented construction, innovative building material, paper materials, renewable resources

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6582 Neural Changes Associated with Successful Antidepressant Treatment in Adolescents with Major Depressive Disorder

Authors: Dung V. H. Pham, Kathryn Cullen

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Introduction: 40% of adolescents with major depression (MDD) are unresponsive to 1st line antidepressant treatment. The neural mechanism underlying treatment-responsive and treatment-resistant depression in adolescent are unclear. Amygdala is important for emotion processing and has been implicated in mood disorders. Past research has shown abnormal amygdala connectivity in adolescents with MDD. This research study changes in amygdala resting-state functional connectivity to find neural correlates of successful antidepressant treatment. Methods: Thirteen adolescents aged 12-19 underwent rfMRI before and after 8-week antidepressant treatment and completed BDI-II at each scan. A whole-brain approach, using anatomically defined amygdala ROIs (1) identified brain regions that are highly synchronous with the amygdala, (2) correlated neural changes with changes in overall depression and specific symptom clusters within depression. Results: Some neural correlates were common across domains: (1) decreased amygdala RSFC with the default mode network (posterior cingulate, precuneus) is associated with improvement in overall depression and many symptom clusters, (2) increased amygdala RSFC with fusiform gyrus is associated with symptom improvement across many symptom clusters. We also found unique neural changes associated with symptom improvement in each symptom cluster. Conclusion: This is the first preliminary study that looks at neural correlates of antidepressant treatment response to overall depression as well as different clusters of symptoms of depression. The finding suggests both overlapping and distinct neural mechanisms underlying improvement in each symptom clusters within depression. Some brain regions found are also implicated in MDD among adults in previous literature.

Keywords: depression, adolescents, fMRI, antidepressants

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6581 Antihyperglycaemic and Antihyperlipidemic Activities of Pleiogynium timorense Seeds and Identification of Bioactive Compounds

Authors: Ataa A. Said, Elsayed A. Abuotabl, Gehan F. Abdel Raoof, Khaled Y. Mohamed

Abstract:

The aim of this study is to evaluate antihyperglycaemic and antihyperlipidemic activities of Pleiogynium timorense (DC.) Leenh (Anacardiaceae) seeds as well as to isolate and identify the bioactive compounds. Antihyperglycaemic effect was evaluated by measuring the effect of two dose levels (150 and 300 mg/kg) of 70% methanol extract of Pleiogynium timorense seeds on blood glucose level when administered 45 minutes before glucose loading. In addition, the effect of the plant extract on the lipid profile was determined by measuring serum total lipids (TL), total cholesterol (TC), triglycerides (TG), high density lipoprotein cholesterol (HDL-C) and low density lipoprotein cholesterol (LDL-C). Furthermore, the bioactive compounds were isolated and identified by chromatographic and spectrometric methods.The results showed that the methanolic extract of the seeds significantly reduced the levels of blood glucose,(TL), (TC), (TG) and (LDL-C) but no significant effect on (HDL-C) comparing with control group. Furthermore, four phenolic compound were isolated which were identified as; catechin, gallic acid, para methoxy benzaldehyde and pyrogallol which were isolated for the first time from the plant. In addition sulphur -containing compound (sulpholane) was isolated for the first time from the plant and from the family. To our knowledge, this is the first study about antihyperglycaemicand antihyperlipidemic activities of the seeds of Pleiogyniumtimorense and its bioactive compounds. So, the methanolic extract of the seeds of Pleiogynium timorense could be a step towards the development of new antihyperglycaemic and antihyperlipidemic drugs.

Keywords: antihyperglycaemic, bioactive compounds, phenolic, Pleiogynium timorense, seeds

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6580 Distribution of Phospholipids, Cholesterol and Carotenoids in Two-Solvent System during Egg Yolk Oil Solvent Extraction

Authors: Aleksandrs Kovalcuks, Mara Duma

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Egg yolk oil is a concentrated source of egg bioactive compounds, such as fat-soluble vitamins, phospholipids, cholesterol, carotenoids and others. To extract lipids and other fat-soluble nutrients from liquid egg yolk, a two-step extraction process involving polar (ethanol) and non-polar (hexane) solvents were used. This extraction technique was based on egg yolk bioactive compounds polarities, where non-polar compound was extracted into non-polar hexane, but polar in to polar alcohol/water phase. But many egg yolk bioactive compounds are not strongly polar or non-polar. Egg yolk phospholipids, cholesterol and pigments are amphipatic (have both polar and non-polar regions) and their behavior in ethanol/hexane solvent system is not clear. The aim of this study was to clarify the behavior of phospholipids, cholesterol and carotenoids during extraction of egg yolk oil with ethanol and hexane and determine the loss of these compounds in egg yolk oil. Egg yolks and egg yolk oil were analyzed for phospholipids (phosphatidylcholine (PC) and phosphatidylethanolamine (PE)), cholesterol and carotenoids (lutein, zeaxanthin, canthaxanthin and β-carotene) content using GC-FID and HPLC methods. PC and PE are polar lipids and were extracted into polar ethanol phase. Concentration of PC in ethanol was 97.89% and PE 99.81% from total egg yolk phospholipids. Due to cholesterol’s partial extraction into ethanol, cholesterol content in egg yolk oil was reduced in comparison to its total content presented in egg yolk lipids. The highest amount of lutein and zeaxanthin was concentrated in ethanol extract. The opposite situation was observed with canthaxanthin and β-carotene, which became the main pigments of egg yolk oil.

Keywords: cholesterol, egg yolk oil, lutein, phospholipids, solvent extraction

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6579 Energy Strategies for Long-Term Development in Kenya

Authors: Joseph Ndegwa

Abstract:

Changes are required if energy systems are to foster long-term growth. The main problems are increasing access to inexpensive, dependable, and sufficient energy supply while addressing environmental implications at all levels. Policies can help to promote sustainable development by providing adequate and inexpensive energy sources to underserved regions, such as liquid and gaseous fuels for cooking and electricity for household and commercial usage. Promoting energy efficiency. Increased utilization of new renewables. Spreading and implementing additional innovative energy technologies. Markets can achieve many of these goals with the correct policies, pricing, and regulations. However, if markets do not work or fail to preserve key public benefits, tailored government policies, programs, and regulations can achieve policy goals. The main strategies for promoting sustainable energy systems are simple. However, they need a broader recognition of the difficulties we confront, as well as a firmer commitment to specific measures. Making markets operate better by minimizing pricing distortions, boosting competition, and removing obstacles to energy efficiency are among the measures. Complementing the reform of the energy industry with policies that promote sustainable energy. Increasing investments in renewable energy. Increasing the rate of technical innovation at each level of the energy innovation chain. Fostering technical leadership in underdeveloped nations by transferring technology and enhancing institutional and human capabilities. promoting more international collaboration. Governments, international organizations, multilateral financial institutions, and civil society—including local communities, business and industry, non-governmental organizations (NGOs), and consumers—all have critical enabling roles to play in the problem of sustainable energy. Partnerships based on integrated and cooperative approaches and drawing on real-world experience will be necessary. Setting the required framework conditions and ensuring that public institutions collaborate effectively and efficiently with the rest of society are common themes across all industries and geographical areas in order to achieve sustainable development. Powerful tools for sustainable development include energy. However, significant policy adjustments within the larger enabling framework will be necessary to refocus its influence in order to achieve that aim. Many of the options currently accessible will be lost or the price of their ultimate realization (where viable) will grow significantly if such changes don't take place during the next several decades and aren't started right enough. In any case, it would seriously impair the capacity of future generations to satisfy their demands.

Keywords: sustainable development, reliable, price, policy

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6578 Single Atom Manipulation with 4 Scanning Tunneling Microscope Technique

Authors: Jianshu Yang, Delphine Sordes, Marek Kolmer, Christian Joachim

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Nanoelectronics, for example the calculating circuits integrating at molecule scale logic gates, atomic scale circuits, has been constructed and investigated recently. A major challenge is their functional properties characterization because of the connecting problem from atomic scale to micrometer scale. New experimental instruments and new processes have been proposed therefore. To satisfy a precisely measurement at atomic scale and then connecting micrometer scale electrical integration controller, the technique improvement is kept on going. Our new machine, a low temperature high vacuum four scanning tunneling microscope, as a customer required instrument constructed by Omicron GmbH, is expected to be scaling down to atomic scale characterization. Here, we will present our first testified results about the performance of this new instrument. The sample we selected is Au(111) surface. The measurements have been taken at 4.2 K. The atomic resolution surface structure was observed with each of four scanners with noise level better than 3 pm. With a tip-sample distance calibration by I-z spectra, the sample conductance has been derived from its atomic locally I-V spectra. Furthermore, the surface conductance measurement has been performed using two methods, (1) by landing two STM tips on the surface with sample floating; and (2) by sample floating and one of the landed tips turned to be grounding. In addition, single atom manipulation has been achieved with a modified tip design, which is comparable to a conventional LT-STM.

Keywords: low temperature ultra-high vacuum four scanning tunneling microscope, nanoelectronics, point contact, single atom manipulation, tunneling resistance

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6577 Outcomes Following Overcorrecting Minus Lens Therapy for Intermittent Distance Exotropia

Authors: Alasdair Warwick, Luna Dhir

Abstract:

Aim: To ascertain the efficacy of overcorrecting minus lens therapy in intermittent distance exotropia. Methods: Retrospective audit of all intermittent distance exotropia patients seen in the Chelsea and Westminster Hospital pediatric eye clinic between 1st January 2014 and 1st March 2016. Change in LogMAR visual acuity, stereopsis, near and distance angles of deviation, as well as the proportions of patients converting to exophoria or undergoing strabismus surgery, were recorded. Results: 22 patients were identified, 45% male, mean age 5 years (range 0.6 to 18.5 years). The median overminus prescription was -1.0 dioptres (range -0.5 to -1.75 dioptres) and mean follow-up was 15 months (range 3 to 54 months). Visual acuity, near and distance angles of deviation improved but were not statistically significant: -0.15 LogMAR, -0.2 prism dioptres and -1.2 prism dioptres respectively (p>0.05). However, a significant change in stereopsis was observed: -74'' (p<0.01). 27% underwent strabismus surgery and 36% converted to exophoria whilst wearing their overminus prescription. Conclusions: Overcorrecting minus lens therapy is an effective therapy for intermittent distance exotropia. There was no deterioration in visual acuity and a significant improvement in stereopsis was seen in our cohort, with many patients converting to an exophoria. The proportion of patients requiring strabismus surgery was comparable to other studies. Further, follow-up is needed to ascertain long-term outcomes.

Keywords: exotropia, overcorrecting minus lens, refraction, strabismus

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6576 Value Relevance of Good Governance: A Study on Listed Companies in the UK

Authors: Ashiqul Amin Khan, Mohsin Ul Amin Khan

Abstract:

The aim of this research is to find the relationship between good governance and shareholder wealth maximisation. The concept of good governance has become more objective in nature over time through various regulations, professionalisation, and practices. This has led to a number of methods for scoring and ranking corporate governance practices. Since shareholder wealth maximisation remains the key corporate goal for managers and governors alike, the effect of good governance in increasing the value of corporations is commented to be an important aspect. In measuring the value relevance of good governance, statistical measures of various yields of listed companies in the UK have been used in this research. Yields reflect required returns on investments from different investment tenets. Historical yields, calculated using historical fundamental data of such companies, reflect expected yields to a great extent. These yields, in turn, reflect the expected risk premium and growth associated with the stocks of the companies. Using fundamental data, the yields have been adjusted to reflect the risk premium required by the investors along various value paradigms. Good governance should naturally lead to lower required risk premium since good corporate governance provided assurance to the investors in terms of sustainability of future performance and desired financial conduct. This, in turn, increases the wealth of stockholders. The findings of this research confirm such nature of the relationship between good governance and value of the company in the long run.

Keywords: corporate governance, good governance practices, short-termism, shareholder value relevance, wealth maximisation, yield

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6575 Phosphate Sludge Ceramics: Effects of Firing Cycle Parameters on Technological Properties and Ceramic Suitability

Authors: Mohamed Loutou, Mohamed Hajjaji, Mohamed Ait Babram, Mohammed Mansori, Rachid Hakkou, Claude Favotto

Abstract:

More than 26,4 million tons of phosphates are produced by the phosphates industries in Morocco (2010), generating huge amounts of sludge by flocculation during the ore beneficiation. They way are stored at the end of the process in open air ponds. Its accumulation and storage may have an impact on several scales such as ground water and human being. For this purpose, an efficient way to use it the field of the ceramic is proposed. The as received sludge and a clay-rich sediment have been studied in terms of chemical, mineralogical and micro-structural side using various analytical methods. Several formulations have been performed by mixing the sludge with the binder shaped in the form of granules. After being dried at 105 °C, the samples were heated in the range of 900-1200 °C. As well as the ceramic properties (firing shrinkage, water absorption, total porosity and compressive strength) the micro structure has been investigated using X-ray diffraction, scanning electron microscopy and Fourier transform infrared spectroscopy. The relations between properties and the operating factors were formulated using the design of experiments (DOE). Gehlenite was the only phase neo-formed in the sintering samples. SEM micrographs revealed the presence of nano metric stains. Based on RSM results, all factors had positive effects on Firing shrinkage, compressive strength and total porosity. However, they manifested opposite effects on density and water absorption.

Keywords: phosphate sludge, clay, ceramic properties, granule

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6574 Organ Donation after Medical Aid in Dying: A Critical Study of Clinical Processes and Legal Rules in Place

Authors: Louise Bernier

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Under some jurisdictions (including Canada), eligible patients can request and receive medical assistance in dying (MAiD) through lethal injections, inducing their cardiocirculatory death. Those same patients can also wish to donate their organs in the process. If they qualify as organ donors, a clinical and ethical rule called the 'dead donor rule' (DDR) requires the transplant teams to wait after cardiocirculatory death is confirmed, followed by a 'no touch' period (5 minutes in Canada) before they can proceed with organ removal. The medical procedures (lethal injections) as well as the delays associated with the DDR can damage organs (mostly thoracic organs) due to prolonged anoxia. Yet, strong scientific evidences demonstrate that operating differently and reconsidering the DDR would result in more organs of better quality available for transplant. This idea generates discomfort and resistance, but it is also worth considering, especially in a context of chronic shortage of available organs. One option that could be examined for MAiD’ patients who wish and can be organ donors would be to remove vital organs while patients are still alive (and under sedation). This would imply accepting that patient’s death would occur through organ donation instead of lethal injections required under MAiD’ legal rules. It would also mean that patients requesting MAiD and wishing to be organ donors could aspire to donate better quality organs, including their heart, an altruistic gesture that carries important symbolic value for many donors and their families. Following a patient centered approach, our hypothesis is that preventing vital organ donation from a living donor in all circumstance is neither perfectly coherent with how legal mentalities have evolved lately in the field of fundamental rights nor compatible with the clinical and ethical frameworks that shape the landscape in which those complex medical decisions unfold. Through a study of the legal, ethical, and clinical rules in place, both at the national and international levels, this analysis raises questions on the numerous inconsistencies associated with respecting the DDR with patients who have chosen to die through MAiD. We will begin with an assessment of the erosion of certain national legal frameworks that pertain to the sacred nature of the right to life which now also includes the right to choose how one wishes to die. We will then study recent innovative clinical protocols tested in different countries to help address acute organ shortage problems in creative ways. We will conclude this analysis with an ethical assessment of the situation, referring to principles such as justice, autonomy, altruism, beneficence, and non-malfeasance. This study will build a strong argument in favor of starting to allow vital organ donations from living donors in countries where MAiD is already permitted.

Keywords: altruism, autonomy, dead donor rule, medical assistance in dying, non-malfeasance, organ donation

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6573 The Effects of Prolonged Social Media Use on Student Health: A Focus on Computer Vision Syndrome, Hand Pain, and Headaches and Mental Status

Authors: Augustine Ndudi Egere, Shehu Adamu, Esther Ishaya Solomon

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As internet accessibility and smartphones continue to increase in Nigeria, Africa’s most populous country, social media platforms have become ubiquitous, causing students of 18-25 age brackets to spend more time on social media. The research investigated the impact of prolonged social media use on the physical health of students, with a specific focus on computer vision syndrome, hand pain, headaches and mental status. The study adopted a mixed-methods approach combining quantitative surveys to gather statistical data on usage patterns and symptoms, along with qualitative interviews into the experiences and perceptions of medical practitioners concerning cases under study within the geopolitical region. The result was analyzed using Regression analysis. It was observed that there is a significant correlation between social media usage by the students in the study age bracket concerning computer vision syndrome, hand pain, headache and general mental status. The research concluded by providing valuable insights into potential interventions and strategies to mitigate the adverse effects of excessive social media use on student well-being and recommends, among others, that educational institutions, parents, and students themselves collaborate to implement strategies aimed at promoting responsible and balanced use of social media.

Keywords: social media, student health, computer vision syndrome, hand pain, headaches, mental staus

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6572 Survival Outcomes Related to Treatment Modalities in Patients with Oropharyngeal Squamous Cell Carcinoma

Authors: Danni Cheng

Abstract:

Purpose:Surgicallyinclusive treatment(SIT)isthemajor treatment fororopharyngealsquamouscellcarcinoma (OPSCC) in Eastern countries, while nonsurgical treatments(NSTs) are the priority treatment in Western countries. The preferred treatmentsforOPSCC patients remaindebated. Methods:Atotalof 153 consecutive OPSCC casesdiagnosed between 2009 and 2019inWCH, and 15,400 OPSCC cases from SEER database (2000-2017) were obtained. Clinical characteristics, treatments, and survival outcomes were retrospectively collected. We conductedKaplan-Meier curves univariate and multivariate analysis to compare the prognosis of OPSCC patients in WCH, SEER Asian, and SEER all ethnic population by different treatment modalities,HPVstatus, ages, and TNM stages. Results: The 5-year overall survival rate was 59% in WCH, 64% in the SEER all ethnic and 67% in SEER Asian group. In both univariate and multivariate analysis, SIT was observed as a consistent benefit factor for OPSCC patients in all three populations when classified by genders, tumor stages, and HPV status. Patients who underwent SIT had significantly better survival outcomes than those who received NSTsin WCH, SEER Asian, and SEER all ethnic groups. HPV positive status was the beneficial factor of OPSCC patients in all three groups. Besides, male patients had worse survival outcomes in both WCH and SEER Asian group, whereas male patients had better outcomes in the SEER all ethnic group. Conclusion: In contrast to nowadaysNSTs are the first-line therapiesfor OPSCC, our ten-year real-world data and SEER data indicated that OPSCC patients who underwent SIT had better prognosis than NSTs.

Keywords: OPSCC, survival outcome, SEER, treatment modalities

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6571 Exploring the Intricate Microbiology of Street Cuisine: Delving into Potential Dangers in Order to Enhance Safety and Quality

Authors: Raana Babadi Fathipour

Abstract:

Street foods hold a significant place in the tapestry of socioeconomic and cultural norms, beloved across the globe. Serving as a convenient and affordable option for city dwellers seeking nourishment, these culinary delights also serve as a vital source of income for vendors, particularly women. Additionally, street food acts as a mirror reflecting traditional local customs and practices, an element that draws tourists to experience the authenticity of a culture firsthand. Despite its many virtues, concerns have emerged regarding the microbiological safety of street food worldwide. Often prepared and sold in subpar conditions without proper oversight or regulation, street food has become synonymous with potential health risks. The presence of elevated levels of fecal indicator bacteria and various pathogens in these unregulated delicacies further perpetuates anxieties surrounding their consumption. This analysis delves into the intricate microbiological intricacies inherent in street food, shedding light on the pertinent safety concerns and prevalent pathogens. Additionally, it elaborates on the worldwide standing of this vital economic endeavor. Moreover, it advocates for the adoption of molecular detection techniques over conventional culture-based methods to gain a more comprehensive grasp of the true microbial risks posed by street cuisine. Acknowledgment marks the initial step towards resolving any given issue.

Keywords: foodborne pathogens, microbiological safety, street food, viruses

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6570 Household Socioeconomic Factors Associated with Teenage Pregnancies in Kigali City, Rwanda

Authors: Dieudonne Uwizeye, Reuben Muhayiteto

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Teenage pregnancy is a challenging problem for sustainable development due to restrictions it poses to socioeconomic opportunities for young mothers, their children and families. Being unable to take appropriate economic and social responsibilities, teen mothers get trapped into poverty and become economic burden to their family and country. Besides, teenage pregnancy is also a health problem because children born to very young mothers are vulnerable with greater risk of illnesses and deaths, and teenage mothers are more likely to be exposed to greater risk of maternal mortality and to other health and psychological problems. In Kigali city, in Rwanda, teenage pregnancy rate is currently high and its increase in recent years is worrisome. However, only individual factors influencing the teenage pregnancy tend to be the basis of interventions. It is important to understand the important socioeconomic factors at the household level that are associated with teenage pregnancy to help government, parents, and other stakeholders to appropriately address the problem with sustainable measures. This study analyzed secondary data from the Fifth Rwanda Demographic and Health Survey (RDHS-V 2014-2015) conducted by the National Institute of Statistics of Rwanda (NISR). The aim was to examine household socio-economic factors that are associated with incidence of teenage pregnancies in Kigali city. In addition to descriptive analysis, Pearson’s Chi Square and Binary Logistic Regression were used in the analysis. Findings indicate that marital status and age of household head, number of members in a household, number of rooms used for sleeping, educational level of the household head and household's wealth are significantly associated with teenage pregnancy in Rwanda ( p< 0.05). It was found that teenagers living with parents, those having parents with higher education and those from richer families are less likely to become pregnant. Age of household head was pinpointed as factor to teenage pregnancy, with teenage-headed households being more vulnerable. The findings also revealed that household composition correlates with the probability of teenage pregnancy (p < 0.05) with teenagers from households with less number of members being more vulnerable. Regarding the size of the house, the study suggested that the more rooms available in households, the less incidences of teenage pregnancy are likely to be observed (p < 0.05). However, teenage pregnancy was not significantly associated with physical violence among parents (p = 0.65) and sex of household heads (p = 0.52), except in teen-headed households of which female are predominantly heads. The study concludes that teenage pregnancy remains a serious social, economic and health problem in Rwanda. The study informs government officials, parents and other stakeholders to take interventions and preventive measures through community sex education, policies and strategies to foster effective parental guidance, care and control of young girls through meeting their necessary social and financial needs within households.

Keywords: household socio-economic factors, Rwanda, Rwanda demographic and health survey, teenage pregnancy

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6569 Effects of Swimming Exercise Training on Persistent Pain in Rats after Thoracotomy

Authors: Shao-Cyuan Yewang, Yu-Wen Chen

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Background: Exercise training is well known to alleviate chronic pain syndromes improve of chronic pain. This study investigated the effect of swimming exercise training on thoracotomy and rib retraction-induced allodynia. Methods: Male Sprague Dawley rats that received animal model of persistent postthoracotomy pain. All rats were divided into three groups: sham operations group (Sham), thoracotomy and rib retraction group (TRR), and TRR with swimming exercise training for 90min/day, 7 days a week for 4 weeks (TRR-SEW). The sham group did not receive retraction of the ribs. Thus, they received a pleural incision. The levels of mechanical and cold allodynia were measured by von Frey and acetone test. Results: In von Frey test, the level of mechanical allodynia in the TRR group was significantly higher than the sham group. The level of mechanical allodynia in the TRR-SEW group was significantly lower than the TRR group. In acetone test, the level of cold allodynia in the TRR group was significantly higher than the sham group. The level of cold allodynia in the TRR-SEW group was significantly lower than the TRR group. Conclusions: These results suggest that swimming exercise training decreases persistent postthoracotomy pain caused by TRR surgery. It may provide one of the new therapeutic effects of swimming exercise training could alleviate persistent postthoracotomy pain.

Keywords: chronic pain, thoracotomy pain, swimming, von Frey test, acetone test

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6568 Improving the Teaching of Mathematics at University Using the Inverted Classroom Model: A Case in Greece

Authors: G. S. Androulakis, G. Deli, M. Kaisari, N. Mihos

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Teaching practices at the university level have changed and developed during the last decade. Implementation of inverted classroom method in secondary education consists of a well-formed basis for academic teachers. On the other hand, distance learning is a well-known field in education research and widespread as a method of teaching. Nonetheless, the new pandemic found many Universities all over the world unprepared, which made adaptations to new methods of teaching a necessity. In this paper, we analyze a model of an inverted university classroom in a distance learning context. Thus, the main purpose of our research is to investigate students’ difficulties as they transit to a new style of teaching and explore their learning development during a semester totally different from others. Our teaching experiment took place at the Business Administration department of the University of Patras, in the context of two courses: Calculus, a course aimed at first-year students, and Statistics, a course aimed at second-year students. Second-year students had the opportunity to attend courses in the university classroom. First-year students started their semester with distance learning. Using a comparative study of these two groups, we explored significant differences in students’ learning procedures. Focused group interviews, written tests, analyses of students’ dialogues were used in a mixed quantity and quality research. Our analysis reveals students’ skills, capabilities but also a difficulty in following, non-traditional style of teaching. The inverted classroom model, according to our findings, offers benefits in the educational procedure, even in a distance learning environment.

Keywords: distance learning, higher education, inverted classroom, mathematics teaching

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6567 A Survey on General Health Status of Paddy Field Workers in Mazandaran Province Using the GHQ-28 Questionnaire

Authors: Sharifirad M., Poursaeed A., Lashgarara F., Mirdamadi S. M.

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Introduction: Paddy farming has been reported as one of the most important causes of non-fatal injuries and occupational accidents among farmers. The ignorance of the health of farmers can cause harm to farmers and lead to disability. As a result, these health consequences can result in less exploitation and economic growth in households. Therefore, this study aimed to determine the general health status of paddy field workers in Mazandaran province, Iran. Materials & Methods: This cross-sectional descriptive study evaluated 384 paddy farmers in Mazandaran province, Iran, who were selected using stratified random sampling. The required data were collected using the standard questionnaire of GHQ-28 with four domains of somaticsymptoms, anxiety and insomnia, social dysfunction, and symptoms of depression. The obtained data were then analyzed using SPSS software (version 25) through Spearman, Kendall, Mann-Whitney, and Kruskal-Wallis tests. Findings: The highest number of participants in this study was in the age group of 50-59 years, with a mean age of 46.9 years. According to the results, the total general health score was obtained at 64.3% for the subjects. Moreover, the scores of four areas of general health were determined at 91.1% (depression symptoms), 73.4% (social dysfunction), 48.7% (anxiety symptoms and insomnia), and 47.1% (somatic symptoms) in descending order. Discussions& Conclusions: The general health of the studied population was not in a good range. In addition, the most observed disorder in the general health of paddy farmers was related to the symptoms of depression, followed by somatic symptoms.

Keywords: general-health, mazandaran, paddyfield

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6566 Heightening Pre-Service Teachers’ Attitude towards Learning and Metacognitive Learning through Information and Communication Technology: Pre-Service Science Teachers’ Perspective

Authors: Abiodun Ezekiel Adesina, Ijeoma Ginikanwa Akubugwo

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Information and Communication Technology, ICT can heighten pre-service teachers’ attitudes toward learning and metacognitive learning; however, there is a dearth of literature on the perception of the pre-service teachers on heightening their attitude toward learning and metacognitive learning. Thus, this study investigates the perception of pre-service science teachers on heightening their attitude towards learning and metacognitive learning through ICT. Two research questions and four hypotheses guided the research. A mixed methods research was adopted for the study in concurrent triangulation type of integrating qualitative and quantitative approaches to the study. The cluster random sampling technique was adopted to select 250 pre-service science teachers in Oyo township. Two self-constructed instruments: Heightening Pre-service Science Teachers’ Attitude towards Learning and Metacognitive Learning through Information and Communication Technology Scale (HPALMIS, r=.73), and an unstructured interview were used for data collection. Thematic analysis, frequency counts and percentages, t-tests, and analysis of variance were used for data analysis. The perception level of the pre-service science teachers on heightening their attitude towards learning and metacognitive learning through ICT is above average, with the majority perceiving that ICT can enhance their thinking about their learning. The perception was significant (mean=92.68, SD=10.86, df=249, t=134.91, p<.05). The perception was significantly differentiated by gender (t=2.10, df= 248, p<.05) in favour of the female pre-service teachers and based on the first time of ICTs use (F(5,244)= 9.586, p<.05). Lecturers of science and science related courses should therefore imbibe the use of ICTs in heightening pre-service teachers’ attitude towards learning and metacognitive learning. Government should organize workshops, seminars, lectures, and symposia along with professional bodies for the science education lecturers to keep abreast of the trending ICT.

Keywords: pre-service teachers’ attitude towards learning, metacognitive learning, ICT, pre-service teachers’ perspectives

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6565 Conservative Treatment Versus Percutaneous Wire Fixation in treatment of Distal Radial Fracture in Elderly

Authors: Abdelfatah Elsenosy, Mahmoud Ebrahim

Abstract:

Background: Distal radius fractures are commonly encountered in orthopedic practice, especially in elderly patients. A number of clinical papers have supported the idea that anatomic restoration of the distal end of the radius is essential to gain superior results. Aim and objectives: The aim of the study is to systematically review the literature for the management of distal end radius in elderly persons (conservative treatment versus percutaneous wire fixation) as regards radiological and functional outcomes. Subjects and methods: Studies were identified from the Medline, Cochrane, EMBASE, and Google Scholar databases were searched until 2019 using combinations of the following search terms: distal radius fracture, conservative treatment, non-operative treatment, and nonsurgical treatment, surgical treatment, operative, elderly, and older. Reference lists of relevant studies were manually searched. Results: There was no statistical significance difference between CI and PKF groups’ frequency of complication in all of the selected studies. Based on the results, we recommend more analysis regarding every parameter of the radiographic and functional results and specific complications related to each fixation need to be accomplished, which requires more Randomized controlled trials (RCTs) with high quality. Conclusion: Surgical treatment seems to be more effective distal radius fracture compared with conservative treatment when the radiographic outcomes were analyzed, and no significant differences were detected in the functional outcomes and complication rate.

Keywords: radius, fracture, surgical, RCTs, conservative, radiographic, outcomes, orthopedic

Procedia PDF Downloads 138
6564 Modeling Local Warming Trend: An Application of Remote Sensing Technique

Authors: Khan R. Rahaman, Quazi K. Hassan

Abstract:

Global changes in climate, environment, economies, populations, governments, institutions, and cultures converge in localities. Changes at a local scale, in turn, contribute to global changes as well as being affected by them. Our hypothesis is built on a consideration that temperature does vary at local level (i.e., termed as local warming) in comparison to the predicted models at the regional and/or global scale. To date, the bulk of the research relating local places to global climate change has been top-down, from the global toward the local, concentrating on methods of impact analysis that use as a starting point climate change scenarios derived from global models, even though these have little regional or local specificity. Thus, our focus is to understand such trends over the southern Alberta, which will enable decision makers, scientists, researcher community, and local people to adapt their policies based on local level temperature variations and to act accordingly. Specific objectives in this study are: (i) to understand the local warming (temperature in particular) trend in context of temperature normal during the period 1961-2010 at point locations using meteorological data; (ii) to validate the data by using specific yearly data, and (iii) to delineate the spatial extent of the local warming trends and understanding influential factors to adopt situation by local governments. Existing data has brought the evidence of such changes and future research emphasis will be given to validate this hypothesis based on remotely sensed data (i.e. MODIS product by NASA).

Keywords: local warming, climate change, urban area, Alberta, Canada

Procedia PDF Downloads 336
6563 Gas Chromatography Coupled to Tandem Mass Spectrometry and Liquid Chromatography Coupled to Tandem Mass Spectrometry Qualitative Determination of Pesticides Found in Tea Infusions

Authors: Mihai-Alexandru Florea, Veronica Drumea, Roxana Nita, Cerasela Gird, Laura Olariu

Abstract:

The aim of this study was to investigate the residues of pesticide found in tea water infusions. A multi-residues method to determine 147 pesticides has been developed using the QuEChERS (Quick, Easy, Cheap, Effective, Rugged, Safe) procedure and dispersive solid phase extraction (d-SPE) for the cleanup the pesticides from complex matrices such as plants and tea. Sample preparation was carefully optimized for the efficient removal of coextracted matrix components by testing more solvent systems. Determination of pesticides was performed using GC-MS/MS (100 of pesticides) and LC-MS/MS (47 of pesticides). The selected reaction monitoring (SRM) mode was chosen to achieve low detection limits and high compounds selectivity and sensitivity. Overall performance was evaluated and validated according to DG-SANTE Guidelines. To assess the pesticide residue transfer rate (qualitative) from dried tea in infusions the samples (tea) were spiked with a mixture of pesticides at the maximum residues level accepted for teas and herbal infusions. In order to investigate the release of the pesticides in tea preparations, the medicinal plants were prepared in four ways by variation of water temperature and the infusion time. The pesticides from infusions were extracted using two methods: QuEChERS versus solid-phase extraction (SPE). More that 90 % of the pesticides studied was identified in infusion.

Keywords: tea, solid-phase extraction (SPE), selected reaction monitoring (SRM), QuEChERS

Procedia PDF Downloads 204
6562 A Static Android Malware Detection Based on Actual Used Permissions Combination and API Calls

Authors: Xiaoqing Wang, Junfeng Wang, Xiaolan Zhu

Abstract:

Android operating system has been recognized by most application developers because of its good open-source and compatibility, which enriches the categories of applications greatly. However, it has become the target of malware attackers due to the lack of strict security supervision mechanisms, which leads to the rapid growth of malware, thus bringing serious safety hazards to users. Therefore, it is critical to detect Android malware effectively. Generally, the permissions declared in the AndroidManifest.xml can reflect the function and behavior of the application to a large extent. Since current Android system has not any restrictions to the number of permissions that an application can request, developers tend to apply more than actually needed permissions in order to ensure the successful running of the application, which results in the abuse of permissions. However, some traditional detection methods only consider the requested permissions and ignore whether it is actually used, which leads to incorrect identification of some malwares. Therefore, a machine learning detection method based on the actually used permissions combination and API calls was put forward in this paper. Meanwhile, several experiments are conducted to evaluate our methodology. The result shows that it can detect unknown malware effectively with higher true positive rate and accuracy while maintaining a low false positive rate. Consequently, the AdaboostM1 (J48) classification algorithm based on information gain feature selection algorithm has the best detection result, which can achieve an accuracy of 99.8%, a true positive rate of 99.6% and a lowest false positive rate of 0.

Keywords: android, API Calls, machine learning, permissions combination

Procedia PDF Downloads 321
6561 “By Failing To Prepare, We Prepare to Fail”: Inadequate Preparedness in Disaster Relief Nursing

Authors: Mary Holstein

Abstract:

Objective: The aim of this study was to evaluate nurse leader confidence in emergency management and disaster preparedness in the state of Texas. My project was a replication study of a survey conducted in 2022 by Reedy et al, for members of the Northwest Organization for Nurse Leaders (NONL). Background: In 2022, the American Association of Colleges of Nursing (AACN) approved new essentials for academic nursing education programs to demonstrate competencies in disaster management, yet no integration of such information into nursing curriculum had been reported in the literature. Research replicated by members of the Texas Organization for Nursing Leadership suggested significant gaps in nurse leader confidence across roles and in structured education that prepares nurse leaders across the spectrum of experience to lead in a crisis. Methods: An exploratory, cross-sectional survey used a sample of 86 RNs who were members of TONL. Results: Results replicated comparable results with significant variance in nurse leader confidence across roles, experience, and previous disaster-related education. Positive associations regarding nurse leaders' confidence in managing disasters were obvious with more advanced positions, further education, and mandatory training. Conclusions: Nursing leaders in Texas lack mandatory and structured education to prepare for emergency and disaster management. The call for mandatory emergency management training and disaster preparedness for nurse leaders remains unmet.

Keywords: confidence, disaster, education, emergency

Procedia PDF Downloads 53
6560 Comparison of Corneal Curvature Measurements Conducted with Tomey AO-2000® and the Current Standard Biometer IOL Master®

Authors: Mohd Radzi Hilmi, Khairidzan Mohd Kamal, Che Azemin Mohd Zulfaezal, Ariffin Azrin Esmady

Abstract:

Purpose: Corneal curvature (CC) is an important anterior segment parameter. This study compared CC measurements conducted with two optical devices in phakic eyes. Methods: Sixty phakic eyes of 30 patients were enrolled in this study. CC was measured three times with the optical biometer and topography-keratometer Tomey AO-2000 (Tomey Corporation, Nagoya, Japan), then with the standard partial optical coherence interferometry (PCI) IOL Master (Carl Zeiss Meditec, Dublin, CA) and data were statistically analysed. Results: The measurements resulted in a mean CC of 43.86 ± 1.57 D with Tomey AO-2000 and 43.84 ± 1.55 D with IOL Master. Distribution of data is normal, and no significance difference in CC values was detected (P = 0.952) between the two devices. Correlation between CC measurements was highly significant (r = 0. 99; P < 0.0001). The mean difference of CC values between devices was 0.017 D and 95% limit of agreement was -0.088 to 0.12. Duration taken for measurements with the standard biometer IOL Master was longer (55.17 ± 2.24 seconds) than with Tomey AO-2000 (39.88 ± 2.38 seconds) in automatic mode. Duration of manual measurement with Tomey AO-2000 in manual mode was the shortest (28.57 ± 2.71 seconds). Conclusion: In phakic eyes, CC measured with Tomey AO-2000 and IOL Master showed similar values, and high correlation was observed between these two devices. This shows that both devices can be used interchangeably. Tomey AO-2000 is better in terms of faster to operate and has its own topography systems.

Keywords: corneal topography, corneal curvature, IOL Master, Tomey AO2000

Procedia PDF Downloads 374
6559 Effect of Two Types of Shoe Insole on the Dynamics of Lower Extremities Joints in Individuals with Leg Length Discrepancy during Stance Phase of Walking

Authors: Mansour Eslami, Fereshte Habibi

Abstract:

Limb length discrepancy (LLD), or anisomeric, is defined as a condition in which paired limbs are noticeably unequal. Individuals with LLD during walking use compensatory mechanisms to dynamically lengthen the short limb and shorten the long limb to minimize the displacement of the body center of mass and consequently reduce body energy expenditure. Due to the compensatory movements created, LLD greater than 1 cm increases the odds of creating lumbar problems and hip and knee osteoarthritis. Insoles are non-surgical therapies that are recommended to improve the walking pattern, pain and create greater symmetry between the two lower limbs. However, it is not yet clear what effect insoles have on the variables related to injuries during walking. The aim of the present study was to evaluate the effect of internal and external heel lift insoles on pelvic kinematic in sagittal and frontal planes and lower extremity joint moments in individuals with mild leg length discrepancy during the stance phase of walking. Biomechanical data of twenty-eight men with structural leg length discrepancy of 10-25 mm were collected while they walked under three conditions: shoes without insole (SH), with internal heel lift insoles (IHLI) in shoes, and with external heal lift insole (EHLI). The tests were performed for both short and long legs. The pelvic kinematic and joint moment were measured with a motion capture system and force plate. Five walking trials were performed for each condition. The average value of five successful trials was used for further statistical analysis. Repeated measures ANCOVA with Bonferroni post hoc test were used for between-group comparisons (p ≤ 0.05). In both internal and external heel lift insoles (IHLI, EHLI), there was a significant decrease in the peak values of lateral and anterior pelvic tilts of the long leg, hip, and knee moments of a long leg and ankle moment of short leg (p ≤ 0.05). Furthermore, significant increases in peak values of lateral and anterior pelvic tilt of short leg in IHLI and EHLI were observed as compared to Shoe (SH) condition (p ≤ 0.01). In addition, a significant difference was observed between the IHLI and EHLI conditions in peak anterior pelvic tilt of long leg and plantar flexor moment of short leg (p=0.04; p= 0.04 respectively). Our findings indicate that both IHLI and EHLI can play an important role in controlling excessive pelvic movements in the sagittal and frontal planes in individuals with mild LLD during walking. Furthermore, the EHLI may have a better effect in preventing musculoskeletal injuries compared to the IHLI.

Keywords: kinematic, leg length discrepancy, shoe insole, walking

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6558 The Effect of Naringenin on the Apoptosis in T47D Cell Line of Breast Cancer

Authors: AliAkbar Hafezi, Jahanbakhsh Asadi, Majid Shahbazi, Alijan Tabarraei, Nader Mansour Samaei, Hamed Sheibak, Roghaye Gharaei

Abstract:

Background: Breast cancer is the most common cancer in women. In most cancer cells, apoptosis is blocked. As for the importance of apoptosis in cancer cell death and the role of different genes in its induction or inhibition, the search for compounds that can begin the process of apoptosis in tumor cells is discussed as a new strategy in anticancer drug discovery. The aim of this study was to investigate the effect of Naringenin (NGEN) on the apoptosis in the T47D cell line of breast cancer. Materials and Methods: In this experimental study in vitro, the T47D cell line of breast cancer was selected as a sample. The cells at 24, 48, and 72 hours were treated with doses of 20, 200, and 1000 µm of Naringenin. Then, the transcription levels of the genes involved in apoptosis, including Bcl-2, Bax, Caspase 3, Caspase 8, Caspase 9, P53, PARP-1, and FAS, were assessed using Real Time-PCR. The collected data were analyzed using IBM SPSS Statistics 24.0. Results: The results showed that Naringenin at doses of 20, 200, and 1000 µm in all three times of 24, 48, and 72 hours increased the expression of Caspase 3, P53, PARP-1 and FAS and reduced the expression of Bcl-2 and increased the Bax/Bcl-2 ratio, nevertheless in none of the studied doses and times, had not a significant effect on the expression of Bax, Caspase 8 and Caspase 9. Conclusion: This study indicates that Naringenin can reduce the growth of some cancer cells and cause their deaths through increased apoptosis and decreased anti-apoptotic Bcl-2 gene expression and, resulting in the induction of apoptosis via both internal and external pathways.

Keywords: apoptosis, breast cancer, naringenin, T47D cell line

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6557 Assessment of the Physical and Chemical Characteristics of Ugbogui River, Edo State, Nigeria

Authors: Iyagbaye O. Rich, Omoigberale O. Michael, Iyagbaye A. Louis

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The physical, chemical parameters and some trace contents of Ugbogui in Edo State, Nigeria were investigated from August 2015 to April 2016. Four stations were studied from upstream to downstream using standard methods. A total of thirty-three (33) physical and chemical characteristics and trace metal contents were examined; Air and water temperatures, depth, transparency, colour, turbidity, flow velocity, pH, total alkalinity, conductivity and dissolved solids etc. Other includes dissolved oxygen, oxygen saturation, biochemical oxygen demand, chloride, phosphate, sodium, nitrate, sulphate, potassium, calcium, magnesium, iron, lead, copper, zinc, nickel, cadmium, vanadium and chromium. Eleven (11) parameters exhibited clear seasonal variations. However, there were high significant differences (p < 0.01) in the values of depth, colour, total suspended solid, biochemical oxygen demand, chemical oxygen demand, chloride, bicarbonate, phosphate, sulphate, iron, manganese, zinc, copper, chromium and cadmium among the stations. The anthropogenic activities had negatively impacted at station 3 of the river, although most of the recorded values were still within permissible limits.

Keywords: anthropogenic activities, Nigeria, permissible limits, physical and chemical parameters, trace metal, water quality

Procedia PDF Downloads 120
6556 Preprocessing and Fusion of Multiple Representation of Finger Vein patterns using Conventional and Machine Learning techniques

Authors: Tomas Trainys, Algimantas Venckauskas

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Application of biometric features to the cryptography for human identification and authentication is widely studied and promising area of the development of high-reliability cryptosystems. Biometric cryptosystems typically are designed for patterns recognition, which allows biometric data acquisition from an individual, extracts feature sets, compares the feature set against the set stored in the vault and gives a result of the comparison. Preprocessing and fusion of biometric data are the most important phases in generating a feature vector for key generation or authentication. Fusion of biometric features is critical for achieving a higher level of security and prevents from possible spoofing attacks. The paper focuses on the tasks of initial processing and fusion of multiple representations of finger vein modality patterns. These tasks are solved by applying conventional image preprocessing methods and machine learning techniques, Convolutional Neural Network (SVM) method for image segmentation and feature extraction. An article presents a method for generating sets of biometric features from a finger vein network using several instances of the same modality. Extracted features sets were fused at the feature level. The proposed method was tested and compared with the performance and accuracy results of other authors.

Keywords: bio-cryptography, biometrics, cryptographic key generation, data fusion, information security, SVM, pattern recognition, finger vein method.

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6555 Regioselective Nucleophilic Substitution of the Baylis-Hillman Adducts with Iodine

Authors: Zahid Shafiq, Li Liu, Dong Wang, Yong-Jun Chen

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As synthetic organic methods are increasingly concerned with the growing importance of sustainable chemistry, iodine recently has emerged as an inexpensive, non-toxic, readily available and environmentally benign catalyst for various organic transformations to afford the corresponding products in high yields with high regio- and chemoselectivity. Iodine has found widespread applications in various organic synthesis such as Michael addition, coupling reaction and also in the multicomponent synthesis where it can efficiently activate C=C, C=O, C=N, and so forth. Iodine not only has been shown to be an efficient mild Lewis acid in various processes, but also due to its moderate nature, and water tolerance, reactions catalyzed by iodine can be effectively carried out in neutral media under very mild conditions. We have successfully described an efficient procedure for the nucleophilic substitution of the Baylis-Hillman (BH) adducts and their corresponding acetates with indoles to get α-substitution product using catalytic Silver Triflate (AgOTf) as Lewis acid. At this point, we were interested to develop an environmentally benign catalytic system to effect this substitution reaction and to avoid the use of metal Lewis acid as a catalyst. Since, we observed the formation of -product during the course of the reaction, we also became interested to explore the reaction conditions in order to control regioselectivity and to obtain both regioisomers. The developed methodology resulted in regioselective substitution products with controlled selectivity. Further, the substitution products were used to synthesize various Tri- and Tetracyclo Azepino indole derivatives via reductive amination.

Keywords: indole, regioselective, Baylis-Hillman, substitution

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