Search results for: random search
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 3878

Search results for: random search

2048 Effects of Internet Addiction on Students’ Academic Performance among Some Tertiary Institutions in Oyo State, Nigeria

Authors: Mujidat Lola Olugbode

Abstract:

This study investigates the effects of internet addiction on academic performance among students in some tertiary institutions in Oyo State, Nigeria. A descriptive survey research design was adopted for the study. Two research questions and two hypotheses were answered and tested. The population of the study comprised of all students in five tertiary institutions in Oyo State, Nigeria. Simple random sampling technique was used to select 2550 participants (respondents) from the institutions used for the study, this constituted the sample for the study. The instruments used for data collection was a self-constructed questionnaire on Internet Addiction and Students Academic Performance (IAASAP). The reliability coefficient of the instrument was 0.77. Data collected were analyzed using frequency and percentages, Pearson Product Moment Correlation coefficient (PPMCC) and t-test analysis. The results showed that the students in tertiary institutions in Oyo State were occasionally addicted to internet use. The study also revealed a positive correlation between internet addiction and academic performance. The findings also showed that there was significant difference in the internet addiction between male and female Students. Based on the above findings, the researchers recommended among others that government, educators, parents, counselors, teachers should help redirect the internet use toward academics to ensure greater academic performance.

Keywords: internet, addiction, internet addiction, academic performance, tertiary institution, students

Procedia PDF Downloads 62
2047 Streamline Marketing Strategies for Survival of Librarianship in Developing Countries in the 21st Century: A Study Related to Sri Lanka

Authors: Wilfred Jeyatheese Jeyaraj

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Considering the current digital age, Library Marketing, in its entirety, has evolved to elucidate the importance of falling back to the roots of searching for tangible and intangible resources, traversing through pages and references to acquire the required knowledge needs with proper guidance. With the turn of the century, the present generation has deeply entrenched their virtual presence, browsing via search engines for all their information needs. Not fully realizing the adverse effects of the materials available digitally, the authenticity of such resources cannot be verified. So a user might be led to believe false misdirected data. This paper tends to elucidate the prominent strategies to market Sri Lankan libraries in a proper manner so as to captivate a large user base making them aware that all resources and materials that they access without guidance outside the libraries are also available within the libraries with added guidance towards accessing the right data. The main contemplation here is to focus on getting more users to visit libraries in person to copiously apprehend the importance of browsing for materials with the proper direction. The current library marketing strategies in Sri Lankan libraries need to be streamlined to align with the best interest of acquiring the present generations to visit libraries in person to reap its benefits.

Keywords: accessibility, librarianship, marketing, Sri Lanka

Procedia PDF Downloads 283
2046 Meningeal Hemangiopericytoma in an HIV-Positive Patient: A Case Report and Review of Literature

Authors: Roland Benedict Reyes, Marc Edsel Ayes, Regina Berba, Cybele Lara Abad

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Background: Three AIDS-defining malignancies have been associated with the human immunodeficiency virus (HIV): Kaposi’s sarcoma, non-Hodgkin’s lymphoma, and cervical carcinoma. However, new cases of non-AIDS defining malignancies also have been increasingly associated with HIV. One of these is a rare intracranial malignancy, meningeal hemangiopericyotma. Case Description: A 32-year old HIV-positive male, not on highly active antiretroviral therapy, was admitted to our hospital due to generalized weakness and sudden onset hearing loss. Cranial MRI was done, which revealed a temporal nodule with the following considerations: granuloma, meningioma or metastases. A craniotomy was performed and the mass excised. Results from the biopsy showed meningeal hemangiopericytoma. The patient was then started on antiretroviral therapy (Lamivudine, Tenofovir, and Efavirenz) and was discharged for radiation therapy and metastatic work-up as an outpatient. On follow-up seven months later, metastatic work up revealed multiple hepatic foci not previously documented suggestive of metastasis short of biopsy sampling. Conclusions: This case of an intracranial hemangiopericytoma in an HIV-positive patient is the second case thus far presented, based on our systematic and extensive search of the literature.

Keywords: Hemangiopericytoma, Human Immunodeficiency Virus, Meningeal hemangiopericytoma, Neoplasm

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2045 Development of Geo-computational Model for Analysis of Lassa Fever Dynamics and Lassa Fever Outbreak Prediction

Authors: Adekunle Taiwo Adenike, I. K. Ogundoyin

Abstract:

Lassa fever is a neglected tropical virus that has become a significant public health issue in Nigeria, with the country having the greatest burden in Africa. This paper presents a Geo-Computational Model for Analysis and Prediction of Lassa Fever Dynamics and Outbreaks in Nigeria. The model investigates the dynamics of the virus with respect to environmental factors and human populations. It confirms the role of the rodent host in virus transmission and identifies how climate and human population are affected. The proposed methodology is carried out on a Linux operating system using the OSGeoLive virtual machine for geographical computing, which serves as a base for spatial ecology computing. The model design uses Unified Modeling Language (UML), and the performance evaluation uses machine learning algorithms such as random forest, fuzzy logic, and neural networks. The study aims to contribute to the control of Lassa fever, which is achievable through the combined efforts of public health professionals and geocomputational and machine learning tools. The research findings will potentially be more readily accepted and utilized by decision-makers for the attainment of Lassa fever elimination.

Keywords: geo-computational model, lassa fever dynamics, lassa fever, outbreak prediction, nigeria

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2044 Ingini Seeds: A Qualitative Study on Its Use in Water Purification in the Dry Zone of Sri Lanka

Authors: Iranga Weerakkody, Palitha Sri Geegana Arachchige, Dasith Tilakaratna

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The aim of this research is to study how folk wisdom can be applied to assist in the process of purification of water. This is qualitative research, and by random sampling, it is focused on to the dry zone of Sri Lanka. The research limitation has been set to the use of Ingini seeds (Strychnos potatorum) to purify water. Here the research is based on connecting traditional knowledge regarding water purification using Ingini seeds to modern times and the advantages and disadvantages of using Ingini seeds to purify water sources. Ingini seeds have been used among villagers of the dry zone to purify water for a long time by methods such as planting Ingini plants around water sources and depositing seeds covered with a cotton cloth inside wells. Crushed Ingini seeds have been put into clay water pots to reduce the hardness of water, as well as the number of impurities present in the water. This shows that Ingini seeds have a property that is successful in precipitating dissolved impurities in water. Ingini seeds are also used to precipitate solid impurities in herbal wine. The advantages of using Ingini seeds are that it can be obtained naturally from the ecology without an additional cost and that it is completely organic forest produce. Another specialty is that in practices, it is used to treat kidney stones and other water-related diseases affecting the kidneys.

Keywords: folklife, Ingini seeds, Strychnos potatorum, organic forest produce, water purification

Procedia PDF Downloads 192
2043 Human-Tiger Conflict in Chitwan National Park, Nepal

Authors: Abishek Poudel

Abstract:

Human-tiger conflicts are serious issues of conflicts between local people and park authority and the conflicting situation potentially play negative role in park management. The study aimed (1) To determine the trend and nature of human-tiger conflicts (2) To understand people's perception and mitigation measures towards tiger conservation. Both primary and secondary information were used to determine human- tiger conflicts in Chitwan National Park. Systematic random sampling with 5% intensity was done to collect the perception of the villagers regarding human-tiger conflicts. The study sites were selected based on frequencies of incidences of human attacks and livestock depredation viz. Rajahar and Ayodhyapuri VDCs respectively. The trend of human casualties by tiger has increased in last five year whereas the trend of livestock has decreased. Reportedly, between 2008 and 2012, tigers killed 22 people, injured 10 and killed at least 213 livestock. Conflict was less common in the park and more intense in the sub-optimal habitats of Buffer Zone. Goat was the most vulnerable livestock followed by cattle. The livestock grazing and human intrusion into tiger habitat were the causes of conflicts. Developing local stewardship and support for tiger conservation, livestock insurance, and compensation policy simplification may help reduce human-tiger conflicts.

Keywords: livestock depredation, sub optimal habitat, human-tiger, local stewardship

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2042 Guadua Bamboo as Eco-Friendly Element in Interior Design and Architecture

Authors: Sarah Noaman

Abstract:

Utilizing renewable resources has become extensive solution for most problems in Egypt nowadays. It plays role in environmental issues such as energy crisis, lake of natural resources and climate change. This paper focuses on the importance of working with the key concepts of creating eco-friendly spaces in Egypt by using traditional perennial plants, such as Guadua bamboo as renewable resources in structures manufacture. Egypt is in critical need to search for alternative raw materials. Thus, this paper focuses on studying the usage of neglected yet affordable materials, such as Guadua bamboo in light weight structures and digital fabrication. Guadua bamboo has been cultivated throughout in tropical and subtropical areas. In Egypt, they exist in many rural areas where people try to control their growth by using pesticides as it serves no economic purpose. This paper aims to discuss the usage of Guadua bamboo either in its original state or after fabrication in the context of interior design and architecture. The results will show the applicability of using perennial plants as complementary materials in the manufacturing processes; also the conclusion will focus the lights on the importance of re-forming shallow water plants in interior design and architecture.

Keywords: digital fabrication, Guadua bamboo, zero-waste material, sustainable material, interior architecture

Procedia PDF Downloads 151
2041 Fundamental Problems in the Operation of the Automotive Parts Industry Small and Medium Businesses in the Greater Bangkok and Perimeter

Authors: Thepnarintra Praphanphat

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The purposes of this study were to: 1) investigate operation conditions of SME automotive part industry in Bangkok and vicinity and 2) to compare operation problem levels of SME automotive part industry in Bangkok and vicinity according to the sizes of the enterprises. Samples in this study included 196 entrepreneurs of SME automotive part industry in Bangkok and vicinity derived from simple random sampling and calculation from R. V. Krejcie and D. W. Morgan’s tables. Research statistics included frequency, percentage, mean, standard deviation, and T-test. The results revealed that in general the problem levels of SME automotive part industry in Bangkok and vicinity were high. When considering in details, it was found that the problem levels were high at every aspect, i.e. personal, production, export, finance, and marketing respectively. The comparison of the problem levels according to the sizes of the enterprises revealed statistically significant differences at .05. When considering on each aspect, it was found that the aspect with the statistical difference at .05 included 5 aspects, i.e. production, marketing, finance, personal, and export. The findings also showed that small enterprises faced more severe problems than those of medium enterprises.

Keywords: automotive part industry, operation problems, SME, Perimeter

Procedia PDF Downloads 382
2040 Statistical Randomness Testing of Some Second Round Candidate Algorithms of CAESAR Competition

Authors: Fatih Sulak, Betül A. Özdemir, Beyza Bozdemir

Abstract:

In order to improve symmetric key research, several competitions had been arranged by organizations like National Institute of Standards and Technology (NIST) and International Association for Cryptologic Research (IACR). In recent years, the importance of authenticated encryption has rapidly increased because of the necessity of simultaneously enabling integrity, confidentiality and authenticity. Therefore, at January 2013, IACR announced the Competition for Authenticated Encryption: Security, Applicability, and Robustness (CAESAR Competition) which will select secure and efficient algorithms for authenticated encryption. Cryptographic algorithms are anticipated to behave like random mappings; hence, it is important to apply statistical randomness tests to the outputs of the algorithms. In this work, the statistical randomness tests in the NIST Test Suite and the other recently designed randomness tests are applied to six second round algorithms of the CAESAR Competition. It is observed that AEGIS achieves randomness after 3 rounds, Ascon permutation function achieves randomness after 1 round, Joltik encryption function achieves randomness after 9 rounds, Morus state update function achieves randomness after 3 rounds, Pi-cipher achieves randomness after 1 round, and Tiaoxin achieves randomness after 1 round.

Keywords: authenticated encryption, CAESAR competition, NIST test suite, statistical randomness tests

Procedia PDF Downloads 314
2039 Multivariate Control Chart to Determine Efficiency Measurements in Industrial Processes

Authors: J. J. Vargas, N. Prieto, L. A. Toro

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Control charts are commonly used to monitor processes involving either variable or attribute of quality characteristics and determining the control limits as a critical task for quality engineers to improve the processes. Nonetheless, in some applications it is necessary to include an estimation of efficiency. In this paper, the ability to define the efficiency of an industrial process was added to a control chart by means of incorporating a data envelopment analysis (DEA) approach. In depth, a Bayesian estimation was performed to calculate the posterior probability distribution of parameters as means and variance and covariance matrix. This technique allows to analyse the data set without the need of using the hypothetical large sample implied in the problem and to be treated as an approximation to the finite sample distribution. A rejection simulation method was carried out to generate random variables from the parameter functions. Each resulting vector was used by stochastic DEA model during several cycles for establishing the distribution of each efficiency measures for each DMU (decision making units). A control limit was calculated with model obtained and if a condition of a low level efficiency of DMU is presented, system efficiency is out of control. In the efficiency calculated a global optimum was reached, which ensures model reliability.

Keywords: data envelopment analysis, DEA, Multivariate control chart, rejection simulation method

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2038 Evaluation of the Impact of Information and Communications Technology (ICT) on the Accuracy of Preliminary Cost Estimates of Building Projects in Nigeria

Authors: Nofiu A. Musa, Olubola Babalola

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The study explored the effect of ICT on the accuracy of Preliminary Cost Estimates (PCEs) prepared by quantity surveying consulting firms in Nigeria for building projects, with a view to determining the desirability of the adoption and use of the technological innovation for preliminary estimating. Thus, data pertinent to the study were obtained through questionnaire survey conducted on a sample of one hundred and eight (108) quantity surveying firms selected from the list of registered firms compiled by the Nigerian Institute of Quantity Surveyors (NIQS), Lagos State Chapter through systematic random sampling. The data obtained were analyzed with SPSS version 17 using student’s t-tests at 5% significance level. The results obtained revealed that the mean bias and co-efficient of variation of the PCEs of the firms are significantly less at post ICT adoption period than the pre ICT adoption period, F < 0.05 in each case. The paper concluded that the adoption and use of the Technological Innovation (ICT) has significantly improved the accuracy of the Preliminary Cost Estimates (PCEs) of building projects, hence, it is desirable.

Keywords: accepted tender price, accuracy, bias, building projects, consistency, information and communications technology, preliminary cost estimates

Procedia PDF Downloads 426
2037 The Use of Emergency Coronary Angiography in Patients Following Out-Of-Hospital Cardiac Arrest and Subsequent Cardio-Pulmonary Resuscitation

Authors: Scott Ashby, Emily Granger, Mark Connellan

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Objectives: 1) To identify if emergency coronary angiography improves outcomes in studies examining OHCA from assumed cardiac aetiology? 2) If so, is it indicated in all patients resuscitated following OHCA, and if not, who is it indicated for? 3) How effective are investigations for screening for the appropriate patients? Background: Out-of-hospital cardiac arrest is one of the leading mechanisms of death, and the most common causative pathology is coronary artery disease. In-hospital treatment following resuscitation greatly affects outcomes, yet there is debate over the most effective protocol. Methods: A literature search was conducted over multiple databases to identify all relevant articles published from 2005. An inclusion criterion was applied to all publications retrieved, which were then sorted by type. Results: A total of 3 existing reviews and 29 clinical studies were analysed in this review. There were conflicting conclusions, however increased use of angiography has shown to improve outcomes in the majority of studies, which cover a variety of settings and cohorts. Recommendations: Currently, emergency coronary angiography appears to improve outcomes in all/most cases of OHCA of assumed cardiac aetiology, regardless of ECG findings. Until a better tool for screening is available to reduce unnecessary procedures, the benefits appear to outweigh the costs/risks.

Keywords: out of hospital cardiac arrest, coronary angiography, resuscitation, emergency medicine

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2036 Adjunct Placement in Educated Nigerian English

Authors: Juliet Charles Udoudom

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In nonnative language use environments, language users have been known to demonstrate marked variations both in the spoken and written productions of the target language. For instance, analyses of the written productions of Nigerian users of English have shown inappropriate sequencing of sentence elements resulting in distortions in meaning and/or other problems of syntax. This study analyses the structure of sentences in the written production of 450 educated Nigerian users of English to establish their sensitivity to adjunct placement and the extent to which it exerts on meaning interpretation. The respondents were selected by a stratified random sampling technique from six universities in south-south Nigeria using education as the main yardstick for stratification. The systemic functional grammar analytic format was used in analyzing the sentences selected from the corpus. Findings from the analyses indicate that of the 8,576 tokens of adjuncts in the entire corpus, 4,550 (53.05%) of circumstantial adjuncts were appropriately placed while 2,839 (33.11%) of modal adjuncts occurred at appropriate locations in the clauses analyzed. Conjunctive adjunct placement accounted for 1,187 occurrences, representing 13.84% of the entire corpus. Further findings revealed that prepositional phrases (PPs) were not well construed by respondents to be capable of realizing adjunct functions, and were inappropriately placed.

Keywords: adjunct, adjunct placement, conjunctive adjunct, circumstantial adjunct, systemic grammar

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2035 Emotional Intelligence and General Self-Efficacy as Predictors of Career Commitment of Secondary School Teachers in Nigeria

Authors: Moyosola Jude Akomolafe

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Career commitment among employees is crucial to the success of any organization. However, career commitment has been reported to be very low among teachers in the public secondary schools in Nigeria. This study, therefore, examined the contributions of emotional intelligence and general self-efficacy to career commitment of among secondary school teachers in Nigeria. Descriptive research design of correlational type was adopted for the study. It made use of stratified random sampling technique was used in selecting two hundred and fifty (250) secondary schools teachers for the study. Three standardized instruments namely: The Big Five Inventory (BFI), Emotional Intelligence Scale (EIS), General Self-Efficacy Scale (GSES) and Career Commitment Scale (CCS) were adopted for the study. Three hypotheses were tested at 0.05 level of significance. Data collected were analyzed through Multiple Regression Analysis to investigate the predicting capacity of emotional intelligence and general self-efficacy on career commitment of secondary school teachers. The results showed that the variables when taken as a whole significantly predicted career commitment among secondary school teachers. The relative contribution of each variable revealed that emotional intelligence and general self-efficacy significantly predicted career commitment among secondary school teachers in Nigeria. The researcher recommended that secondary school teachers should be exposed to emotional intelligence and self-efficacy training to enhance their career commitment.

Keywords: career commitment, emotional intelligence, general self-efficacy, secondary school teachers

Procedia PDF Downloads 387
2034 The Relation between Vitamin C and Oral Health

Authors: Mai Ashraf Talaat

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Background: Vitamin C (ascorbic acid) is an essential nutrient for the development and repair of all body tissues. It can be obtained from a healthy diet or through supplementation. Due to its importance, vitamin C has become a mainstay in the treatment and prevention of many diseases and in maintaining immune, skin, bone and overall health. This review article aims to discuss the studies and case reports conducted to evaluate the effect of Vitamin C on oral health and the recent advances in oral medicine that involve the use of vitamin C. Data/Sources: The review was conducted for clinical studies, case reports and published literature in the English language that addresses this topic. An extensive search in the electronic databases of PubMed, PubMed Central, Web of Science, National Library of Medicine and ResearchGate was performed. Conclusion: Vitamin C is thought to treat periodontal diseases and gingival enlargement. It also affects biofilm formation and therefore, it helps in reducing caries incidence. Recently, vitamin C mesotherapy has been used to treat inflamed gingiva, bleeding gums and gingival hyperpigmentation. More research and randomized controlled trials are needed on this specific topic for more accurate judgment. Clinical significance: A minimally invasive approach - the usage of vitamin C in dental care could drastically reduce the need for surgical intervention.

Keywords: oral health, periodontology, vitamin C, Gingivitis

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2033 Valuation of Entrepreneurship Education (EE) Curriculum and Self-Employment Generation among Graduates of Tertiary Institutions in Edo State, Nigeria

Authors: Angela Obose Oriazowanlan

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Despite the introduction of Entrepreneurship education into the Nigerian University curriculum to prepare graduates for self-employment roles in order to abate employment challenges, their unemployment rate still soars high. The study, therefore, examined the relevance of the curriculum contents and its delivery mechanism to equip graduates with appropriate entrepreneurial skills prior to graduation. Four research questions and two hypotheses guided the study. The survey research design was adopted for the study. An infinite population of graduates of a period of five years with 200 sample representatives using the simple random sampling technique was adopted. A 45-item structured questionnaire was used for data gathering. The gathered data thereof was anlysed using the descriptive statistics of mean and standard deviation, while the formulated hypotheses were tested with Z-score at 0.5 level of significance. The findings revealed, among others, that graduates acquisition of appropriate entrepreneurial skills for self-employment generation is low due to curriculum deficiencies, insufficient time allotment, and the delivery mechanism. It was recommended, among others, that the curriculum should be reviewed to improve its relevancy and that sufficient time should be allotted to enable adequate teaching and learning process.

Keywords: evaluation of entrepreneurship education (EE) curriculum, self-employment generation, graduates of tertiary institutions, Edo state, Nigeria

Procedia PDF Downloads 98
2032 A Lean Manufacturing Profile of Practices in the Metallurgical Industry: A Methodology for Multivariate Analysis

Authors: M. Jonathan D. Morales, R. Ramón Silva

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The purpose of this project is to carry out an analysis and determine the profile of actual lean manufacturing processes in the Metropolitan Area of Bucaramanga. Through the analysis of qualitative and quantitative variables it was possible to establish how these manufacturers develop production practices that ensure their competitiveness and productivity in the market. In this study, a random sample of metallurgic and wrought iron companies was applied, following which a quantitative focus and analysis was used to formulate a qualitative methodology for measuring the level of lean manufacturing procedures in the industry. A qualitative evaluation was also carried out through a multivariate analysis using the Numerical Taxonomy System (NTSYS) program which should allow for the determination of Lean Manufacturing profiles. Through the results it was possible to observe how the companies in the sector are doing with respect to Lean Manufacturing Practices, as well as identify the level of management that these companies practice with respect to this topic. In addition, it was possible to ascertain that there is no one dominant profile in the sector when it comes to Lean Manufacturing. It was established that the companies in the metallurgic and wrought iron industry show low levels of Lean Manufacturing implementation. Each one carries out diverse actions that are insufficient to consolidate a sectoral strategy for developing a competitive advantage which enables them to tie together a production strategy.

Keywords: production line management, metallurgic industry, lean manufacturing, productivity

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2031 The Impact of Efflux Pump Inhibitor on the Activity of Benzosiloxaboroles and Benzoxadiboroles against Gram-Negative Rods

Authors: Agnieszka E. Laudy, Karolina Stępien, Sergiusz Lulinski, Krzysztof Durka, Stefan Tyski

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1,3-dihydro-1-hydroxy-2,1-benzoxaborole and its derivatives are a particularly interesting group of synthetic agents and were successfully employed in supramolecular chemistry medicine. The first important compounds, 5-fluoro-1,3-dihydro-1-hydroxy-2,1-benzoxaborole and 5-chloro-1,3-dihydro-1-hydroxy-2,1-benzoxaborole were identified as potent antifungal agents. In contrast, (S)-3-(aminomethyl)-7-(3-hydroxypropoxy)-1-hydroxy-1,3-dihydro-2,1-benzoxaborole hydrochloride is in the second phase of clinical trials as a drug for the treatment of Gram-negative bacterial infections of the Enterobacteriaceae family and Pseudomonas aeruginosa. Equally important and difficult task is to search for compounds active against Gram-negative bacilli, which have multi-drug-resistance efflux pumps actively removing many of the antibiotics from bacterial cells. We have examined whether halogen-substituted benzoxaborole-based derivatives and their analogues possess antibacterial activity and are substrates for multi-drug-resistance efflux pumps. The antibacterial activity of 1,3-dihydro-3-hydroxy-1,1-dimethyl-1,2,3-benzosiloxaborole and 10 halogen-substituted its derivatives, as well as 1,2-phenylenediboronic acid and 3 synthesised fluoro-substituted its analogs, were evaluated. The activity against the reference strains of Gram-positive (n=5) and Gram-negative bacteria (n=10) was screened by the disc-diffusion test (0.4 mg of tested compounds was applied onto paper disc). The minimal inhibitory concentration values and the minimal bactericidal concentration values were estimated according to The Clinical and Laboratory Standards Institute and The European Committee on Antimicrobial Susceptibility Testing recommendations. During the minimal inhibitory concentration values determination with or without phenylalanine-arginine beta-naphthylamide (50 mg/L) efflux pump inhibitor, the concentrations of tested compounds ranged 0.39-400 mg/L in the broth medium supplemented with 1 mM magnesium sulfate. Generally, the studied benzosiloxaboroles and benzoxadiboroles showed a higher activity against Gram-positive cocci than against Gram-negative rods. Moreover, benzosiloxaboroles have the higher activity than benzoxadiboroles compounds. In this study, we demonstrated that substitution (mono-, di- or tetra-) of 1,3-dihydro-3-hydroxy-1,1-dimethyl-1,2,3-benzosiloxaborole with halogen groups resulted in an increase in antimicrobial activity as compared to the parent substance. Interestingly, the 6,7-dichloro-substituted parent substance was found to be the most potent against Gram-positive cocci: Staphylococcus sp. (minimal inhibitory concentration 6.25 mg/L) and Enterococcus sp. (minimal inhibitory concentration 25 mg/L). On the other hand, mono- and dichloro-substituted compounds were the most actively removed by efflux pumps present in Gram-negative bacteria mainly from Enterobacteriaceae family. In the presence of efflux pump inhibitor the minimal inhibitory concentration values of chloro-substituted benzosiloxaboroles decreased from 400 mg/L to 3.12 mg/L. Of note, the highest increase in bacterial susceptibility to tested compounds in the presence of phenylalanine-arginine beta-naphthylamide was observed for 6-chloro-, 6,7-dichloro- and 6,7-difluoro-substituted benzosiloxaboroles. In the case of Escherichia coli, Enterobacter cloacae and P. aeruginosa strains at least a 32-fold decrease in the minimal inhibitory concentration values of these agents were observed. These data demonstrate structure-activity relationships of the tested derivatives and highlight the need for further search for benzoxaboroles and related compounds with significant antimicrobial properties. Moreover, the influence of phenylalanine-arginine beta-naphthylamide on the susceptibility of Gram-negative rods to studied benzosiloxaboroles indicate that some tested agents are substrates for efflux pumps in Gram-negative rods.

Keywords: antibacterial activity, benzosiloxaboroles, efflux pumps, phenylalanine-arginine beta-naphthylamide

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2030 The Effect of Enamel Surface Preparation on the Self-Etch Bonding of Orthodontic Tubes: An in Vitro Study

Authors: Fernandes A. C. B. C. J., de Jesus V. C., Sepideh N., Vilela OFGG, Somarin K. K., França R., Pinheiro F. H. S. L.

Abstract:

Objective: The purpose of this study was to look at the effect of pre-treatment of enamel with pumice and/or 37% phosphoric acid on the shear bond strength (SBS) of orthodontic tubes bonded to enamel while simultaneously evaluating the efficacy of orthodontic tubes bonded by self-etch primer (SEP). Materials and Methods: 39 of the crown halves were divided into 3 groups at random. Group, I was the control group utilizing both prophy paste and the conventional double etching pre-treatment method. Group II excluded the use of prophy paste prior to double etching. Group III excluded the use of both prophy paste and double etching and only utilized SEP. Bond strength of the orthodontic tubes was measured by SBS. One way ANOVA and Tukey’s HSD test were used to compare SBS values between the three groups. The statistical significance was set to p<0.05. Results: The difference in SBS values of groups I (36.672 ± 9.315 Mpa), II (34.242 ± 9.986 Mpa), and III (39.055 ± 5.565) were not statistically significant (P<0.05). Conclusion: This study suggested that the use of prophy paste or pre-acid etch of the enamel surface did not provide a statistically significant difference in SBS between the three groups.

Keywords: shear bond strength, orthodontic bracket, self-etch primer, pumice, prophy

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2029 Analyzing the Effects of Supply and Demand Shocks in the Spanish Economy

Authors: José M Martín-Moreno, Rafaela Pérez, Jesús Ruiz

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In this paper we use a small open economy Dynamic Stochastic General Equilibrium Model (DSGE) for the Spanish economy to search for a deeper characterization of the determinants of Spain’s macroeconomic fluctuations throughout the period 1970-2008. In order to do this, we distinguish between tradable and non-tradable goods to take into account the fact that the presence of non-tradable goods in this economy is one of the largest in the world. We estimate a DSGE model with supply and demand shocks (sectorial productivity, public spending, international real interest rate and preferences) using Kalman Filter techniques. We find the following results. First of all, our variance decomposition analysis suggests that 1) the preference shock basically accounts for private consumption volatility, 2) the idiosyncratic productivity shock accounts for non-tradable output volatility, and 3) the sectorial productivity shock along with the international interest rate both greatly account for tradable output. Secondly, the model closely replicates the time path observed in the data for the Spanish economy and finally, the model captures the main cyclical qualitative features of this economy reasonably well.

Keywords: business cycle, DSGE models, Kalman filter estimation, small open economy

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2028 Building a Performance Outline for Health Care Workers at Teaching Hospitals, Nigeria: The Role of Different Leadership Styles

Authors: Osuagwu Justine Ugochukwu

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Investigating the effects of transformational and transactional leadership styles on the performance of healthcare employees at the University Teaching Hospital (UNTH) in Enugu, Nigeria, was the goal of the research. The respondents were asked to fill out a structured questionnaire. The respondents were chosen using a straightforward random sampling technique and consisted of 370 health workers at the hospital. The result of the analysis revealed that transactional and transformational leadership style has a positive while ambidextrous leadership has a negative effect on healthcare workers' performance in UNTH, Enugu. Therefore, the management of public hospitals that have the capacity to change their top management approach to leadership styles will gain substantial support from their employees’ thereby increasing organizational commitment and performance among health workers. This will have remarkable social implications, one of which is a change in the work culture and attitude of medical personnel from the seemingly anti-community of patients to friendly engagement and treatment of patients leading to a harmonious coexistence among these individuals in society. Investigating ambidextrous leadership and the use of nonparametric analysis is unique and has brought brand-new knowledge to leadership literature.

Keywords: workers performance, transformational leadership, transactional leadership, governance quality, ambidextrous leadership

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2027 Fuel Quality of Biodiesel from Chlorella protothecoides Microalgae Species

Authors: Mukesh Kumar, Mahendra Pal Sharma

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Depleting fossil fuel resources coupled with serious environmental degradation has led to the search for alternative resources for biodiesel production as a substitute of Petro-diesel. Currently, edible, non-edible oils and microalgal plant species are cultivated for biodiesel production. Looking at the demerits of edible and non-edible oil resources, the focus is being given to grow microalgal species having high oil productivities, less maturity time and less land requirement. Out of various microalgal species, Chlorella protothecoides is considered as the most promising species for biodiesel production owing to high oil content (58 %), faster growth rate (24–48 h) and high biomass productivity (1214 mg/l/day). The present paper reports the results of optimization of reaction parameters of transesterification process as well as the kinetics of transesterification with 97% yield of biodiesel. The measurement of fuel quality of microalgal biodiesel shows that the biodiesel exhibit very good oxidation stability (O.S) of 7 hrs, more than ASTM D6751 (3 hrs) and EN 14112 (6 hrs) specifications. The CP and PP of 0 and -3 °C are finding as per ASTM D 2500-11 and ASTM D 97-12 standards. These results show that the microalgal biodiesel does not need any enhancement in O.S & CFP and hence can be recommended to be directly used as MB100 or its blends into diesel engine operation. Further, scope is available for the production of binary blends using poor quality biodiesel for engine operation.

Keywords: fuel quality, methyl ester yield, microalgae, transesterification

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2026 Attribute Based Comparison and Selection of Modular Self-Reconfigurable Robot Using Multiple Attribute Decision Making Approach

Authors: Manpreet Singh, V. P. Agrawal, Gurmanjot Singh Bhatti

Abstract:

From the last decades, there is a significant technological advancement in the field of robotics, and a number of modular self-reconfigurable robots were introduced that can help in space exploration, bucket to stuff, search, and rescue operation during earthquake, etc. As there are numbers of self-reconfigurable robots, choosing the optimum one is always a concern for robot user since there is an increase in available features, facilities, complexity, etc. The objective of this research work is to present a multiple attribute decision making based methodology for coding, evaluation, comparison ranking and selection of modular self-reconfigurable robots using a technique for order preferences by similarity to ideal solution approach. However, 86 attributes that affect the structure and performance are identified. A database for modular self-reconfigurable robot on the basis of different pertinent attribute is generated. This database is very useful for the user, for selecting a robot that suits their operational needs. Two visual methods namely linear graph and spider chart are proposed for ranking of modular self-reconfigurable robots. Using five robots (Atron, Smores, Polybot, M-Tran 3, Superbot), an example is illustrated, and raking of the robots is successfully done, which shows that Smores is the best robot for the operational need illustrated, and this methodology is found to be very effective and simple to use.

Keywords: self-reconfigurable robots, MADM, TOPSIS, morphogenesis, scalability

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2025 The Impact of Democratic Leadership on Job Satisfaction Among Teachers in South Hebron Directorate Schools

Authors: Mohammad Mahmoud Rjoob

Abstract:

This study aimed to explore the impact of democratic leadership on job satisfaction among teachers in the South Hebron Directorate schools. The study was applied to a random sample representing the study population of teachers in the South Hebron Directorate of Education, with a sample size of 301 teachers from 12 schools. The researcher adopted the descriptive approach as it is the most suitable for the nature of this study, and a questionnaire was used as a tool for data collection and measuring various variables. The study recommended the importance of enhancing the concept of democratic leadership in schools to boost teachers' morale and improve the quality of the educational process. It also encouraged the adoption of democratic leadership styles by administrations, educational areas, and new principals due to their positive and effective impact on job performance. Additionally, the study suggested providing training courses for school principals and new teachers on how to apply the principles of democratic leadership that contribute to creating a positive educational environment and enhance the spirit of cooperation to achieve the school's goals. Finally, the study called for granting school principals more authority and powers to increase their ability to effectively deal with challenges and problems, which contributes to improving the educational process and enhances teachers' job satisfaction.

Keywords: democratic leadership, job satisfaction, teachers, South Hebron Directorate Schools

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2024 Controller Design for Highly Maneuverable Aircraft Technology Using Structured Singular Value and Direct Search Method

Authors: Marek Dlapa

Abstract:

The algebraic approach is applied to the control of the HiMAT (Highly Maneuverable Aircraft Technology). The objective is to find a robust controller which guarantees robust stability and decoupled control of longitudinal model of a scaled remotely controlled vehicle version of the advanced fighter HiMAT. Control design is performed by decoupling the nominal MIMO (multi-input multi-output) system into two identical SISO (single-input single-output) plants which are approximated by a 4th order transfer function. The algebraic approach is then used for pole placement design, and the nominal closed-loop poles are tuned so that the peak of the µ-function is minimal. As an optimization tool, evolutionary algorithm Differential Migration is used in order to overcome the multimodality of the cost function yielding simple controller with decoupling for nominal plant which is compared with the D-K iteration through simulations of standard longitudinal manoeuvres documenting decoupled control obtained from algebraic approach for nominal plant as well as worst case perturbation.

Keywords: algebraic approach, evolutionary computation, genetic algorithms, HiMAT, robust control, structured singular value

Procedia PDF Downloads 138
2023 An Optimal Approach for Full-Detailed Friction Model Identification of Reaction Wheel

Authors: Ghasem Sharifi, Hamed Shahmohamadi Ousaloo, Milad Azimi, Mehran Mirshams

Abstract:

The ever-increasing use of satellites demands a search for increasingly accurate and reliable pointing systems. Reaction wheels are rotating devices used commonly for the attitude control of the spacecraft since provide a wide range of torque magnitude and high reliability. The numerical modeling of this device can significantly enhance the accuracy of the satellite control in space. Modeling the wheel rotation in the presence of the various frictions is one of the critical parts of this approach. This paper presents a Dynamic Model Control of a Reaction Wheel (DMCR) in the current control mode. In current-mode, the required current is delivered to the coils in order to achieve the desired torque. During this research, all the friction parameters as viscous and coulomb, motor coefficient, resistance and voltage constant are identified. In order to model identification of a reaction wheel, numerous varying current commands apply on the particular wheel to verify the estimated model. All the parameters of DMCR are identified by classical Levenberg-Marquardt (CLM) optimization method. The experimental results demonstrate that the developed model has an appropriate precise and can be used in the satellite control simulation.

Keywords: experimental modeling, friction parameters, model identification, reaction wheel

Procedia PDF Downloads 232
2022 Modelling of Filters CO2 (Carbondioxide) and CO (Carbonmonoxide) Portable in Motor Vehicle's Exhaust with Absorbent Chitosan

Authors: Yuandanis Wahyu Salam, Irfi Panrepi, Nuraeni

Abstract:

The increased of greenhouse gases, that is CO2 (carbondioxide) in atmosphere induce the rising of earth’s surface average temperature. One of the largest contributors to greenhouse gases is motor vehicles. Smoke which is emitted by motor’s exhaust containing gases such as CO2 (carbondioxide) and CO (carbon monoxide). Chemically, chitosan is cellulose like plant fiber that has the ability to bind like absorbant foam. Chitosan is a natural antacid (absorb toxins), when chitosan is spread over the surface of water, chitosan is able to absorb fats, oils, heavy metals, and other toxic substances. Judging from the nature of chitosan is able to absorb various toxic substances, it is expected that chitosan is also able to filter out gas emission from the motor vehicles. This study designing a carbondioxide filter in the exhaust of motor vehicles using chitosan as its absorbant. It aims to filter out gases in the exhaust so that CO2 and CO can be reducted before emitted by exhaust. Form of this reseach is study of literature and applied with experimental research of tool manufacture. Data collected through documentary studies by studying books, magazines, thesis, search on the internet as well as the relevant reference. This study will produce a filters which has main function to filter out CO2 and CO emissions that generated by vehicle’s exhaust and can be used as portable.

Keywords: filter, carbon, carbondioxide, exhaust, chitosan

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2021 An Assessment of the Impact of Safe Motherhood Initiative on Maternal Health of Women in Gumel Local Government Area of Jigawa State, Nigeria

Authors: Ahmed Mudi, Bala Zakar

Abstract:

The paper assesses the impact of safe motherhood initiative on maternal health of women in Gumel Local Government Area of Jigawa State. The work will specifically concentrate on the background on safe motherhood scheme and maternal health of women. The objective of this paper is to assess the level of safe motherhood scheme in Gumel local government area, to find out the level of maternal health in Gumel local government as well as to determine the impact of safe motherhood scheme on maternal health on women in Gumel Local Government Area Jigawa State. Various literature on the topic are reviewed, the paper adopts survey design and use questionnaire to collect data from the respondent. The study comprises 350 women selected from six rural communities in Gumel using random sampling techniques, and the data was analysed by simple frequency and percentage. The research concluded that safe motherhood initiative has a significant impact on the maternal health of women in Gumel Local Government Area of Jigawa State. Finally, suitable recommendations were given on how to improve the scheme to ensure better maternal health in the region.

Keywords: action, assessment, maternal health, safe motherhood, surgery

Procedia PDF Downloads 263
2020 Linkages between Postponement Strategies and Flexibility in Organizations

Authors: Polycarpe Feussi

Abstract:

Globalization, technological and customer increasing changes, amongst other drivers, result in higher levels of uncertainty and unpredictability for organizations. In order for organizations to cope with the uncertain and fast-changing economic and business environment, these organizations need to innovate in order to achieve flexibility. In simple terms, the organizations must develop strategies leading to the ability of these organizations to provide horizontal information connections across the supply chain to create and deliver products that meet customer needs by synchronization of customer demands with product creation. The generated information will create efficiency and effectiveness throughout the whole supply chain regarding production, storage, and distribution, as well as eliminating redundant activities and reduction in response time. In an integrated supply chain, spanning activities include coordination with distributors and suppliers. This paper explains how through postponement strategies, flexibility can be achieved in an organization. In order to achieve the above, a thorough literature review was conducted via the search of online websites that contains material from scientific journal data-bases, articles, and textbooks on the subject of postponement and flexibility. The findings of the research are found in the last part of the paper. The first part introduces the concept of postponement and its importance in supply chain management. The second part of the paper provides the methodology used in the process of writing the paper.

Keywords: postponement strategies, supply chain management, flexibility, logistics

Procedia PDF Downloads 191
2019 Awareness in the Code of Ethics for Nurse Educators among Nurse Educators, Nursing Students and Professional Nurses at the Royal Thai Army, Thailand

Authors: Wallapa Boonrod

Abstract:

Thai National Education Act 1999 required all educational institutions received external quality evaluation at least once every five years. The purpose of this study was to compare the awareness in the code of ethics for nurse educators among nurse educators, professional nurses, and nursing students under The Royal Thai Army Nurse College. The sample consisted of 51 of nurse educators 200 nursing students and 340 professional nurses from Army nursing college and hospital by stratified random sampling techniques. The descriptive statistics indicated that the nurse educators, nursing students and professional nurses had different levels of awareness in the 9 roles of nurse educators: Nurse, Reliable Sacrifice, Intelligence, Giver, Nursing Skills, Teaching Responsibility, Unbiased Care, Tie to Organization, and Role Model. The code of ethics for nurse educators (CENE) measurement models from the awareness of nurse educators, professional nurses, and nursing students were well fitted with the empirical data. The CENE models from them were invariant in forms, but variant in factor loadings. Thai Army nurse educators strive to create a learning environment that nurtures the highest nursing potential and standards in their nursing students.

Keywords: awareness of the code of ethics for nurse educators, nursing college and hospital under The Royal Thai Army, Thai Army nurse educators, professional nurses

Procedia PDF Downloads 449