Search results for: association rule mining
Commenced in January 2007
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Edition: International
Paper Count: 4020

Search results for: association rule mining

3450 Association of AGT (M268T) Gene Polymorphism in Diabetes and Nephropathy in Pakistan

Authors: Syed M. Shahid, Rozeena Shaikh, Syeda N. Nawab, Abid Azhar

Abstract:

Diabetes mellitus (DM) is a prevalent non-communicable disease worldwide. DM may lead to many vascular complications like hypertension, nephropathy, retinopathy, neuropathy and foot infections. Pathogenesis of diabetic nephropathy (DN) is implicated by the polymorphisms in genes encoding the specific components of renin angiotensin aldosterone system (RAAS) which include angiotensinogen (AGT), angiotensin-II receptor and angiotensin converting enzyme (ACE) genes. This study was designed to explore the possible association of AG (M268T) polymorphism in the patients of diabetes and nephropathy in Pakistan. Study subjects included 100 controls, 260 diabetic patients without renal insufficiency and 190 diabetic nephropathy patients with persistent albuminuria. Fasting blood samples were collected from all the subjects after getting institutional ethical approval and informed consent. The biochemical estimations, PCR amplification and direct sequencing for the specific region of AGT gene was carried out. A significantly high frequency of TT genotype and T allele of AGT (M268T) was observed in the patients of diabetes with nephropathy as compared to controls and diabetic patients without any known renal impairment. The TT genotype and T allele of AGT (M268T) polymorphism may be considered as a genetic risk factor for the development and progression of nephropathy in diabetes. Further cross sectional population studies would be of help to establish and confirm the observed possible association of AGT gene variations with development of nephropathy in diabetes.

Keywords: RAAS, AGT (M268T), diabetes, nephropathy

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3449 Integrating Data Mining within a Strategic Knowledge Management Framework: A Platform for Sustainable Competitive Advantage within the Australian Minerals and Metals Mining Sector

Authors: Sanaz Moayer, Fang Huang, Scott Gardner

Abstract:

In the highly leveraged business world of today, an organisation’s success depends on how it can manage and organize its traditional and intangible assets. In the knowledge-based economy, knowledge as a valuable asset gives enduring capability to firms competing in rapidly shifting global markets. It can be argued that ability to create unique knowledge assets by configuring ICT and human capabilities, will be a defining factor for international competitive advantage in the mid-21st century. The concept of KM is recognized in the strategy literature, and increasingly by senior decision-makers (particularly in large firms which can achieve scalable benefits), as an important vehicle for stimulating innovation and organisational performance in the knowledge economy. This thinking has been evident in professional services and other knowledge intensive industries for over a decade. It highlights the importance of social capital and the value of the intellectual capital embedded in social and professional networks, complementing the traditional focus on creation of intellectual property assets. Despite the growing interest in KM within professional services there has been limited discussion in relation to multinational resource based industries such as mining and petroleum where the focus has been principally on global portfolio optimization with economies of scale, process efficiencies and cost reduction. The Australian minerals and metals mining industry, although traditionally viewed as capital intensive, employs a significant number of knowledge workers notably- engineers, geologists, highly skilled technicians, legal, finance, accounting, ICT and contracts specialists working in projects or functions, representing potential knowledge silos within the organisation. This silo effect arguably inhibits knowledge sharing and retention by disaggregating corporate memory, with increased operational and project continuity risk. It also may limit the potential for process, product, and service innovation. In this paper the strategic application of knowledge management incorporating contemporary ICT platforms and data mining practices is explored as an important enabler for knowledge discovery, reduction of risk, and retention of corporate knowledge in resource based industries. With reference to the relevant strategy, management, and information systems literature, this paper highlights possible connections (currently undergoing empirical testing), between an Strategic Knowledge Management (SKM) framework incorporating supportive Data Mining (DM) practices and competitive advantage for multinational firms operating within the Australian resource sector. We also propose based on a review of the relevant literature that more effective management of soft and hard systems knowledge is crucial for major Australian firms in all sectors seeking to improve organisational performance through the human and technological capability captured in organisational networks.

Keywords: competitive advantage, data mining, mining organisation, strategic knowledge management

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3448 Prevalence and Distribution of Verocytotoxigenic Escherichia coli (Vtec) Non-O157 Serotypes in Cattle in Abuja, Nigeria

Authors: S. I. Enem, S. I. Oboegbulem

Abstract:

Objective: The most frequently implicated E. coli serotype causing haemorrhagic colitis and haemorrhagic uraemic syndrome (HUS) is VTEC 0157. However, non-O157 VTEC is now known to be as prevalent as VETC O157 infection (or even more) in most parts of the world. The objective of the study was to establish the occurrence of non-O157 VTEC serotypes in cattle in the Federal Capital Territory (FCT) Abuja, Nigeria. The level of significance of the infection with sex, age and season were also tested. Methods: The study was carried out in the FCT, Abuja, Nigeria which is located between latitude 8o and 90 25` North of the equator and longitude 60 45` and 7045` East of the Greenwich meridian. The cross sectional epidemiological method and multi-staged sampling technique were used in this study. Samples were collected from the freshly voided faeces of both apparently healthy and diarrhoeic cattle in selected abattoirs and cattle herds. Enriched samples were analyzed bacteriologically and biochemically after which they were characterised using commercially prepared latex agglutination test kits. Results: A total of 718 faecal samples from cattle were analyzed for the presence of VTEC non-O157. Thirty eight (5.23%) were positive for non-O157. There was no significant association (p > 0.05) between sex and infection with non-O157 VTEC in cattle. There was a significant association (P < 0.05) between age and infection with non-O157 VTEC in cattle. Calves were more associated than the adults. There was also a significant association (P < 0.05) between season and infection with non-O157 VTEC in cattle. The dry season was more associated than the wet season. Conclusion: The study established the occurrence and prevalence of non-O157 VTEC in cattle in FCT, Abuja, Nigeria. As a major food animal in Nigeria, infection in cattle provides an epidemiological causal association to the infection in humans. The result showed that warmer seasons (dry season) stimulate the presence of VTEC infection in animals and thus, as a consequence, increases the number of human cases. The prevalence was also higher in younger calves (< 6 months) probably as a result of undeveloped immune system.

Keywords: prevalence, distribution, Verocytotoxigenic escherichia coli (VTEC), non-O157 serotypes, cattle

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3447 Use of Quasi-3D Inversion of VES Data Based on Lateral Constraints to Characterize the Aquifer and Mining Sites of an Area Located in the North-East of Figuil, North Cameroon

Authors: Fofie Kokea Ariane Darolle, Gouet Daniel Hervé, Koumetio Fidèle, Yemele David

Abstract:

The electrical resistivity method is successfully used in this paper in order to have a clearer picture of the subsurface of the North-East ofFiguil in northern Cameroon. It is worth noting that this method is most often used when the objective of the study is to image the shallow subsoils by considering them as a set of stratified ground layers. The problem to be solved is very often environmental, and in this case, it is necessary to perform an inversion of the data in order to have a complete and accurate picture of the parameters of the said layers. In the case of this work, thirty-three (33) Schlumberger VES have been carried out on an irregular grid to investigate the subsurface of the study area. The 1D inversion applied as a preliminary modeling tool and in correlation with the mechanical drillings results indicates a complex subsurface lithology distribution mainly consisting of marbles and schists. Moreover, the quasi-3D inversion with lateral constraint shows that the misfit between the observed field data and the model response is quite good and acceptable with a value low than 10%. The method also reveals existence of two water bearing in the considered area. The first is the schist or weathering aquifer (unsuitable), and the other is the marble or the fracturing aquifer (suitable). The final quasi 3D inversion results and geological models indicate proper sites for groundwaters prospecting and for mining exploitation, thus allowing the economic development of the study area.

Keywords: electrical resistivity method, 1D inversion, quasi 3D inversion, groundwaters, mining

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3446 Identifying Concerned Citizen Communication Style During the State Parliamentary Elections in Bavaria

Authors: Volker Mittendorf, Andre Schmale

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In this case study, we want to explore the Twitter-use of candidates during the state parliamentary elections-year 2018 in Bavaria, Germany. This paper focusses on the seven parties that probably entered the parliament. Against this background, the paper classifies the use of language as populism which itself is considered as a political communication style. First, we determine the election campaigns which started in the years 2017 on Twitter, after that we categorize the posting times of the different direct candidates in order to derive ideal types from our empirical data. Second, we have done the exploration based on the dictionary of concerned citizens which contains German political language of the right and the far right. According to that, we are analyzing the corpus with methods of text mining and social network analysis, and afterwards we display the results in a network of words of concerned citizen communication style (CCCS).

Keywords: populism, communication style, election, text mining, social media

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3445 Sexting Phenomenon in Educational Settings: A Data Mining Approach

Authors: Koutsopoulou Ioanna, Gkintoni Evgenia, Halkiopoulos Constantinos, Antonopoulou Hera

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Recent advances in Internet Computer Technology (ICT) and the ever-increasing use of technological equipment amongst adolescents and young adults along with unattended access to the internet and social media and uncontrolled use of smart phones and PCs have caused social problems like sexting to emerge. The main purpose of the present article is first to present an analytic theoretical framework of sexting as a recent social phenomenon based on studies that have been conducted the last decade or so; and second to investigate Greek students’ and also social network users, sexting perceptions and to record how often social media users exchange sexual messages and to retrace demographic variables predictors. Data from 1,000 students were collected and analyzed and all statistical analysis was done by the software package WEKA. The results indicate among others, that the use of data mining methods is an important tool to draw conclusions that could affect decision and policy making especially in the field and related social topics of educational psychology. To sum up, sexting lurks many risks for adolescents and young adults students in Greece and needs to be better addressed in relevance to the stakeholders as well as society in general. Furthermore, policy makers, legislation makers and authorities will have to take action to protect minors. Prevention strategies based on Greek cultural specificities are being proposed. This social problem has raised concerns in recent years and will most likely escalate concerns in global communities in the future.

Keywords: educational ethics, sexting, Greek sexters, sex education, data mining

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3444 Heart Failure Identification and Progression by Classifying Cardiac Patients

Authors: Muhammad Saqlain, Nazar Abbas Saqib, Muazzam A. Khan

Abstract:

Heart Failure (HF) has become the major health problem in our society. The prevalence of HF has increased as the patient’s ages and it is the major cause of the high mortality rate in adults. A successful identification and progression of HF can be helpful to reduce the individual and social burden from this syndrome. In this study, we use a real data set of cardiac patients to propose a classification model for the identification and progression of HF. The data set has divided into three age groups, namely young, adult, and old and then each age group have further classified into four classes according to patient’s current physical condition. Contemporary Data Mining classification algorithms have been applied to each individual class of every age group to identify the HF. Decision Tree (DT) gives the highest accuracy of 90% and outperform all other algorithms. Our model accurately diagnoses different stages of HF for each age group and it can be very useful for the early prediction of HF.

Keywords: decision tree, heart failure, data mining, classification model

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3443 Selective Extraction Separation of Vanadium and Chromium in the Leaching/Aqueous Solution with Trioctylamine

Authors: Xiaohua Jing

Abstract:

Efficient extraction for separation of V and Cr in the leaching/aqueous solution is essential to the reuse of V and Cr in the V-Cr slag. Trioctylamine, a common tertiary amine extractant, with some good characters (e.g., weak base, insoluble in water and good stability) different from N1923, was investigated in this paper. The separation factor of Cr and V can be reached to 230.71 when initial pH of the aqueous solution is 0.5, so trioctylamine can be used for extracting Cr from the leaching/aqueous solution contained V and Cr. The highest extraction percentages of Cr and V were 98.73% and 90.22% when the initial pH values were 0.5 and 1.5, respectively. Via FT-IR spectra of loaded organic phase and trioctylamine, the hydrogen bond association mechanism of extracting V and Cr was investigated, which was the same with the way of extracting the two metals with primary amine N1923.

Keywords: selective extraction, trioctylamine, V and Cr, separation factor, hydrogen bond association

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3442 Thrombophilic Risk Factors and Pregnancy Complications

Authors: Hanan Azzam1, Nashwa Abousamra1, Amany Mansour1, Yaser Abd El-dayem2, , Solafa Elsharawy1

Abstract:

Background: Inherited thrombophilias are a heterogenous group of conditions which have been implicated in a variety of pregnancy complications. More recently, deficiency of protein Z (PZ) has been liked to pregnancy complications, including preterm delivery. Aim: We designed this study to evaluate the association of inherited thrombophilias including [Protein C (PC), Protein S (PS), Anti thrombin III (ATIII) deficiency and activated protein C (APC) resistance] and protein Z deficiency with a variety of pregnancy complications. Patients and Methods: 60 women with different pregnancy complications, including 20 patients with preeclampsia, 20 patients with intrauterine growth resistance (IUGR), and 20 patients with intrauterine fetal death (IUFD), in addition to 30 healthy pregnant women were recruited for the present study. PC and free PS antigen, ATIII activity, modified functional APC-resistance, and PZ levels were determined. Results: There was no significant association between inherited thrombophilias and complicated pregnancies as regards PC deficiency (p=1.0), AT III and PS deficiency (p=0.312), and APC-resistance (P=0.083). PZ was significantly associated with complicated pregnancies (p=0.012). Patients with protein Z levels below 1.5 µg/ml were considered deficient. Accordingly, we demonstrated protein Z deficiency in 30% of complicated pregnancies (RR 6.0, 95% CI 1.29-27.90;p=0.022), 20% of preeclampsia (RR 3.5, 95% CI 0.57 – 21.28; P = 0.174), 40% of IUGR (RR 9.3 95% CI 1.72-50.61; P = 0.010) and 30% of IUFD (RR 6, 95% CI 1.07 – 33.64; P = 0.042). Conclusions: These findings indicate the absence of association of inherited thrombophilias, including PC, PS, AT III deficiency, and APC resistance with pregnancy complications. However, PZ deficiency is associated with increased risk of pregnancy complications, especially intrauterine growth restriction and intrauterine fetal death.

Keywords: protein C, protein S, thrombophelia, pregnancy, protein Z

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3441 Association of Sleep Duration and Insomnia with Body Mass Index Among Brazilian Adults

Authors: Giovana Longo-Silva, Risia Cristina Egito de Menezes, Renan Serenini, Márcia de Oliveira Lima, Júlia Souza de Melo, Larissa de Lima Soares

Abstract:

Introduction: Sleep duration and quality have been increasingly recognized as important factors affecting overall health and well-being, including their potential impact on body weight and composition. Previous research has shown inconsistent results regarding the association between sleep patterns and body mass index (BMI), particularly among diverse populations such as Brazilian adults. Understanding these relationships is crucial for developing targeted interventions to address obesity and related health issues. Objective: This study aimed to investigate the association between sleep duration, insomnia, and BMI among Brazilian adults using data from a large national survey focused on chronic nutrition and sleep habits. Materials and Methods: The study included 2050 participants from a population-based virtual survey. BMI was calculated using self-reported weight and height measurements. Participants also reported usual bedtime and wake time on weekdays and weekends and whether they experienced symptoms of insomnia. The average sleep duration across the entire week was calculated as follows: [(5×sleep duration on weekdays) + (2×sleep duration on weekends)]/7. Linear regression analyses were conducted to assess the association between sleep duration, insomnia, and BMI, adjusting for potential confounding factors, including age, sex, marital status, physical exercise duration, and diet quality. Results: After adjusting for confounding variables, the study found that BMI decreased by 0.19 kg/m² for each additional hour of sleep duration (95% CI = -0.37, -0.02; P = 0.03). Conversely, individuals with insomnia had a higher BMI, with an increase of 0.75 kg/m² (95% CI = 0.28, 1.22; P = 0.002) compared to those without insomnia. Conclusions: The findings suggest a significant association between sleep duration, insomnia, and BMI among Brazilian adults. Longer sleep duration was associated with lower BMI, while insomnia was associated with higher BMI. These results underscore the importance of considering sleep patterns in strategies aimed at preventing and managing obesity in this population. Further research is needed to explore the underlying mechanisms and potential interventions targeting sleep-related factors to promote healthier body weight outcomes.

Keywords: sleep, obesity, chronobiology, nutrition

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3440 Proliferative Effect of Some Calcium Channel Blockers on the Human Embryonic Kidney Cell Line

Authors: Lukman Ahmad Jamil, Heather M. Wallace

Abstract:

Introduction: Numerous epidemiological studies have shown a positive as well as negative association and no association in some cases between chronic use of calcium channel blockers and the increased risk of developing cancer. However, these associations were enmeshed with controversies in the absence of laboratory based studies to back up those claims. Aim: The aim of this study was to determine in mechanistic terms the association between the long-term administration of nifedipine and diltiazem and increased risk of developing cancer using the human embryonic kidney (HEK293) cell line. Methods: Cell counting using the Trypan blue dye exclusion and 3-4, 5-Dimethylthiazol-2-yl-2, 5-diphenyl-tetrazolium bromide (MTT) assays were used to investigate the effect of nifedipine and diltiazem on the growth pattern of HEK293 cells. Protein assay using modified Lowry method and analysis of intracellular polyamines concentration using Liquid Chromatography – Tandem Mass Spectrometry (LC-MS) were performed to ascertain the mechanism through which chronic use of nifedipine increases the risk of developing cancer. Results: Both nifedipine and diltiazem significantly increased the proliferation of HEK293 cells dose and time dependently. This proliferative effect after 24, 48 and 72-hour incubation period was observed at 0.78, 1.56 and 25 µM for nifedipine and 0.39, 1.56 and 25 µM for diltiazem, respectively. The increased proliferation of the cells was found to be statistically significantly (p<0.05). Furthermore, the increased proliferation of the cells induced by nifedipine was associated with the increase in the protein content and elevated intracellular polyamines concentration level. Conclusion: The chronic use of nifedipine is associated with increased proliferation of cells with concomitant elevation of polyamines concentration and elevated polyamine levels have been implicated in many malignant transformations and hence, these provide a possible explanation on the link between long term use of nifedipine and development of some human cancers. Further studies are needed to evaluate the cause of this association.

Keywords: cancer, nifedipine, polyamine, proliferation

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3439 Sino-Africa Trade Ties: The Curse of African Minerals: Tweaking the Corporate Scorecard to Benefit the Mining Village Communities

Authors: Donald Ouko

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For decades, Africa has been home to several foreign companies doing business in various sectors. In recent years, China has consistently positioned itself as a development partner powerhouse among African nations. However, this has not been felt as equally beneficial to the local communities where the partnerships bloom in extractives trading. This paper explores the impact of Chinese involvement in mining on the local communities in three African countries, the factors that enable the sector to thrive amid the impacts, and what could be done differently for the local communities to experience a different outcome. It suggests alternative terms of engagement that aim at transparency, accountability, and anti-corruption to ensure inclusive social and economic development, and sound governance both at state and corporate levels.

Keywords: law and society, social development, corporate governance, China-Africa ties, human rights, socio-economic development, accountability, transparency

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3438 Association of Hypoxia-Inducible Factor-1α in Patients with Chronic Obstructive Pulmonary Diseases

Authors: Kriti Upadhyay, Ashraf Ali, Puja Sohal, Randeep Guleria

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Background: In Chronic Obstructive Pulmonary diseases (COPD) pathogenesis oxidative stress plays an important role. Hypoxia-Inducible factor (HIF-1α) is a dimeric protein complex which Functions as a master transcriptional regulator of the adaptive response to hypoxiaand is a risk factor that increases when oxidative stress triggers. The role ofHIF-1αin COPD due to smoking is lacking. Aim: This study aims to evaluate the role of HIF-1α in smoker COPD patients comparing its association with diseases severity. Method: In this cross-sectional study, we recruited 87 subjects, 57 were smokers with COPD,15 were smokers without COPD and other 15 were non-smoker healthy controls. The mean age was 54.6± 9.32 (cases 57.08±8.15; controls 50.0± 9.8). There were 62%smokers, 25% non-smokers,7% tobacco chewers and 6% ex-smokers. Enzyme-linked immune sorbent assay (ELISA) method was used for analyzing serum samples wherein HIF-1α was analyzed by Sandwich-ELISA. Results: In smoker COPD patients, a significantly higher HIF-1α level showed positive association with hypoxia, smoking status and severity of disease (p=0.03). The mean value of HIF-1α was not significantly different in smokers without COPD and healthy controls. Conclusion: It is found that HIF-1α level was increased in smoker COPD, but not in smokers without COPD. This suggests that development of COPD drive the HIF-1α pathway and it correlates with the severity of diseases.

Keywords: COPD, chronic obstructive pulmonary diseases, smokers, nonsmokers, hypoxia

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3437 Evaluating Gene-Gene Interaction among Nicotine Dependence Genes on the Risk of Oral Clefts

Authors: Mengying Wang, Dongjing Liu, Holger Schwender, Ping Wang, Hongping Zhu, Tao Wu, Terri H Beaty

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Background: Maternal smoking is a recognized risk factor for nonsyndromic cleft lip with or without cleft palate (NSCL/P). It has been reported that the effect of maternal smoking on oral clefts is mediated through genes that influence nicotine dependence. The polymorphisms of cholinergic receptor nicotinic alpha (CHRNA) and beta (CHRNB) subunits genes have previously shown strong associations with nicotine dependence. Here, we attempted to investigate whether the above genes are associated with clefting risk through testing for potential gene-gene (G×G) and gene-environment (G×E) interaction. Methods: We selected 120 markers in 14 genes associated with nicotine dependence to conduct transmission disequilibrium tests among 806 Chinese NSCL/P case-parent trios ascertained in an international consortium which conducted a genome-wide association study (GWAS) of oral clefts. We applied Cordell’s method using “TRIO” package in R to explore G×G as well as G×E interaction involving environmental tobacco smoke (ETS) based on conditional logistic regression model. Results: while no SNP showed significant association with NSCL/P after Bonferroni correction, we found signals for G×G interaction between 10 pairs of SNPs in CHRNA3, CHRNA5, and CHRNB4 (p<10-8), among which the most significant interaction was found between RS3743077 (CHRNA3) and RS11636753 (CHRNB4, p<8.2×10-12). Linkage disequilibrium (LD) analysis revealed only low level of LD between these markers. However, there were no significant results for G×ETS interaction. Conclusion: This study fails to detect association between nicotine dependence genes and NSCL/P, but illustrates the importance of taking into account potential G×G interaction for genetic association analysis in NSCL/P. This study also suggests nicotine dependence genes should be considered as important candidate genes for NSCL/P in future studies.

Keywords: Gene-Gene Interaction, Maternal Smoking, Nicotine Dependence, Non-Syndromic Cleft Lip with or without Cleft Palate

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3436 Critical Parameters of a Square-Well Fluid

Authors: Hamza Javar Magnier, Leslie V. Woodcock

Abstract:

We report extensive molecular dynamics (MD) computational investigations into the thermodynamic description of supercritical properties for a model fluid that is the simplest realistic representation of atoms or molecules. The pair potential is a hard-sphere repulsion of diameter σ with a very short attraction of length λσ. When λ = 1.005 the range is so short that the model atoms are referred to as “adhesive spheres”. Molecular dimers, trimers …etc. up to large clusters, or droplets, of many adhesive-sphere atoms are unambiguously defined. This then defines percolation transitions at the molecular level that bound the existence of gas and liquid phases at supercritical temperatures, and which define the existence of a supercritical mesophase. Both liquid and gas phases are seen to terminate at the loci of percolation transitions, and below a second characteristic temperature (Tc2) are separated by the supercritical mesophase. An analysis of the distribution of clusters in gas, meso- and liquid phases confirms the colloidal nature of this mesophase. The general phase behaviour is compared with both experimental properties of the water-steam supercritical region and also with formally exact cluster theory of Mayer and Mayer. Both are found to be consistent with the present findings that in this system the supercritical mesophase narrows in density with increasing T > Tc and terminates at a higher Tc2 at a confluence of the primary percolation loci. The expended plot of the MD data points in the mesophase of 7 critical and supercritical isotherms in highlight this narrowing in density of the linear-slope region of the mesophase as temperature is increased above the critical. This linearity in the mesophase implies the existence of a linear combination rule between gas and liquid which is an extension of the Lever rule in the subcritical region, and can be used to obtain critical parameters without resorting to experimental data in the two-phase region. Using this combination rule, the calculated critical parameters Tc = 0.2007 and Pc = 0.0278 are found be agree with the values found by of Largo and coworkers. The properties of this supercritical mesophase are shown to be consistent with an alternative description of the phenomenon of critical opalescence seen in the supercritical region of both molecular and colloidal-protein supercritical fluids.

Keywords: critical opalescence, supercritical, square-well, percolation transition, critical parameters.

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3435 Educational Attainment Inequalities in Depressive Symptoms in More Than 100 000 Individuals in Europe

Authors: Adam Chlapecka, Anna Kagstrom, Pavla Cermakova

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Background: Increasing educational attainment (EA) could decrease the occurrence of depression. We investigated the relationship between EA and depressive symptoms in older individuals across four European regions. Methods: We studied 108 315 Europeans (54 % women, median age 63 years old) from the Survey on Health, Ageing and Retirement in Europe assessing EA (7 educational levels based on ISCED classification); and depressive symptoms (≥ 4 points on EURO-D scale). Logistic regression estimated the association between EA and depressive symptoms, adjusting for sociodemographic and health-related factors; testing for sex/age/region and education interactions. Results: Higher EA was associated with lower odds of depressive symptoms, independent of sociodemographic and health-related factors. A threshold of the lowest odds of depressive symptoms was detected at the first stage of tertiary education (OR 0.60; 95% CI 0.55-0.65; p<0.001; relative to no education). Central and Eastern Europe showed the strongest association (OR for high vs. low education 0.37; 95% CI 0.33-0.40; p<0.001) and Scandinavia the weakest (OR for high vs. low education 0.69; 95% CI 0.60-0.80; p<0.001). The association was strongest amongst younger individuals. There was a sex and education interaction only within Central and Eastern Europe. Conclusion: The level of EA is reflected in later-life depressive symptoms, suggesting that supporting individuals in achieving EA, and considering those with lower EA at increased risk for depression, could lead to the decreased burden of depression across the life course. Further educational support in Central and Eastern Europe may decrease the higher burden of depressive symptoms in women.

Keywords: depression, education, epidemiology, Europe

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3434 Association of Glutathione S-transferase M1 and T1 Gene Polymorphisms with Vitiligo in Saudi Population

Authors: Ghaleb Bin Huraib, Fahad Al Harthi, Mohammad Mustafa, Abdulrahman Al-Asmari

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Introduction: Vitiligo is an acquired pigmentary skin disorder with the regional disappearance of melanocytes. Vitiligo affects 0.1 to 2% of the global population, and the incidence varies substantially depending on ethnicity. Glutathione S-transferase (GST) is a multigene family of enzymes that detoxify oxidative stress products. The oxidative stress-related GSTM1/GSTT1 genes deletion may cause epidermal melanocytes destruction and the development of vitiligo. Hence, the present study aimed to investigate the association of GST gene polymorphisms with vitiligo in the Saudi population, if any. Materials and Methods: The present study includes 129 vitiligo cases and 130 age-matched healthy controls. The proportion of male and female patients with vitiligo is almost equal. The multiplex polymerase chain reaction (PCR) method was used for polymorphic analysis. Results: Increased odds of generalized vitiligo was observed with the null genotypes of GSTT1- gene (OR = 1.91, 95% CI = 1.07-3.42, p = 0.019). The possible genetic combinations of GSTM1/GSTT1 and their genotypic distribution showed the frequency of GSTM1+/GSTT1+ 62/130 (47.69%) and GSTM1-/GSTT1+ 52/130 (40.00%) were higher in controls than in cases 44/129 (34.11%), 43/129 (33.34%), respectively while GSTM1+/GSTT1- and GSTM1-/GSTT1- null genotypes were higher 22/129 (17.05%) and 20/129 (15.50%) in vitiligo patients as compared to controls 11/130 (8.46%), 5/130 (3.84%), respectively. The strength of association of different genetic combinations with cases have shown GSTM1+/GSTT1- (OR = 2.81, 95% CI = 1.24-6.40, p = 0.009) and GSTM1-/GSTT1- (OR = 5.63, 95% CI = 1.96 - 16.16, p = 0.0004) were significantly higher in vitiligo cases as compared to controls. We did not observe any significant association of age and gender of patients with GST gene polymorphisms. Conclusions: The GSTT1-, GSTM1+/GSTT1- and GSTM1-/GSTT1- null genotypes were significantly associated with vitiligo. These genetic polymorphisms may be the associative genetic risk factor for vitiligo among Saudis. It could be used as a genetic marker for screening vitiligo patients among Saudis. Further studies on GSTs gene polymorphism in larger sample sizes from different geographical areas and ethnicity are needed to strengthen the present findings.

Keywords: vitiligo, GSTM1, GSTT1, gene polymorphism, oxidative stress

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3433 Recidivism in Brazil: Exploring the Case of the Association of Protection and Assistance to Convicts Methodology

Authors: Robyn Heitzman

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The traditional method of punitive justice in Brazil has failed to prevent high levels of recidivism. Combined with overcrowding, a lack of resources, and human rights abuses, the conventional prison approach in Brazil is being questioned; one alternative approach is the association of protection and assistance to convicts (APAC) method. Justice -according to the principles of the APAC methodology- is served through education, reformation, and human development. The model has reported relatively low levels of recidivism and has been internationally recognised for its progress. Through qualitative research such as interviews and case studies, this paper explains why, applying the theory of restorative justice, the APAC methodology yields lower rates of recidivism compared to the traditional models of prisons in Brazil. 

Keywords: Brazil, justice, prisons, restorative

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3432 Neural Networks Models for Measuring Hotel Users Satisfaction

Authors: Asma Ameur, Dhafer Malouche

Abstract:

Nowadays, user comments on the Internet have an important impact on hotel bookings. This confirms that the e-reputation issue can influence the likelihood of customer loyalty to a hotel. In this way, e-reputation has become a real differentiator between hotels. For this reason, we have a unique opportunity in the opinion mining field to analyze the comments. In fact, this field provides the possibility of extracting information related to the polarity of user reviews. This sentimental study (Opinion Mining) represents a new line of research for analyzing the unstructured textual data. Knowing the score of e-reputation helps the hotelier to better manage his marketing strategy. The score we then obtain is translated into the image of hotels to differentiate between them. Therefore, this present research highlights the importance of hotel satisfaction ‘scoring. To calculate the satisfaction score, the sentimental analysis can be manipulated by several techniques of machine learning. In fact, this study treats the extracted textual data by using the Artificial Neural Networks Approach (ANNs). In this context, we adopt the aforementioned technique to extract information from the comments available in the ‘Trip Advisor’ website. This actual paper details the description and the modeling of the ANNs approach for the scoring of online hotel reviews. In summary, the validation of this used method provides a significant model for hotel sentiment analysis. So, it provides the possibility to determine precisely the polarity of the hotel users reviews. The empirical results show that the ANNs are an accurate approach for sentiment analysis. The obtained results show also that this proposed approach serves to the dimensionality reduction for textual data’ clustering. Thus, this study provides researchers with a useful exploration of this technique. Finally, we outline guidelines for future research in the hotel e-reputation field as comparing the ANNs with other technique.

Keywords: clustering, consumer behavior, data mining, e-reputation, machine learning, neural network, online hotel ‘reviews, opinion mining, scoring

Procedia PDF Downloads 137
3431 Power System Stability Enhancement Using Self Tuning Fuzzy PI Controller for TCSC

Authors: Salman Hameed

Abstract:

In this paper, a self-tuning fuzzy PI controller (STFPIC) is proposed for thyristor controlled series capacitor (TCSC) to improve power system dynamic performance. In a STFPIC controller, the output scaling factor is adjusted on-line by an updating factor (α). The value of α is determined from a fuzzy rule-base defined on error (e) and change of error (Δe) of the controlled variable. The proposed self-tuning controller is designed using a very simple control rule-base and the most natural and unbiased membership functions (MFs) (symmetric triangles with equal base and 50% overlap with neighboring MFs). The comparative performances of the proposed STFPIC and the standard fuzzy PI controller (FPIC) have been investigated on a multi-machine power system (namely, 4 machine two area system) through detailed non-linear simulation studies using MATLAB/SIMULINK. From the simulation studies it has been found out that for damping oscillations, the performance of the proposed STFPIC is better than that obtained by the standard FPIC. Moreover, the proposed STFPIC as well as the FPIC have been found to be quite effective in damping oscillations over a wide range of operating conditions and are quite effective in enhancing the power carrying capability of the power system significantly.

Keywords: genetic algorithm, power system stability, self-tuning fuzzy controller, thyristor controlled series capacitor

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3430 Q-Map: Clinical Concept Mining from Clinical Documents

Authors: Sheikh Shams Azam, Manoj Raju, Venkatesh Pagidimarri, Vamsi Kasivajjala

Abstract:

Over the past decade, there has been a steep rise in the data-driven analysis in major areas of medicine, such as clinical decision support system, survival analysis, patient similarity analysis, image analytics etc. Most of the data in the field are well-structured and available in numerical or categorical formats which can be used for experiments directly. But on the opposite end of the spectrum, there exists a wide expanse of data that is intractable for direct analysis owing to its unstructured nature which can be found in the form of discharge summaries, clinical notes, procedural notes which are in human written narrative format and neither have any relational model nor any standard grammatical structure. An important step in the utilization of these texts for such studies is to transform and process the data to retrieve structured information from the haystack of irrelevant data using information retrieval and data mining techniques. To address this problem, the authors present Q-Map in this paper, which is a simple yet robust system that can sift through massive datasets with unregulated formats to retrieve structured information aggressively and efficiently. It is backed by an effective mining technique which is based on a string matching algorithm that is indexed on curated knowledge sources, that is both fast and configurable. The authors also briefly examine its comparative performance with MetaMap, one of the most reputed tools for medical concepts retrieval and present the advantages the former displays over the latter.

Keywords: information retrieval, unified medical language system, syntax based analysis, natural language processing, medical informatics

Procedia PDF Downloads 135
3429 Heavy Metal Contamination of Mining-Impacted Mangrove Sediments and Its Correlation with Vegetation and Sediment Attributes

Authors: Jumel Christian P. Nicha, Severino G. Salmo III

Abstract:

This study investigated the concentration of heavy metals (HM) in mangrove sediments of Lake Uacon, Zambales, Philippines. The relationship among the studied HM (Cr, Ni, Pb, Cu, Cd, Fe) and the mangrove vegetation and sediment characteristics were assessed. Fourteen sampling plots were designated across the lake (10 vegetated and 4 un-vegetated) based on distance from the mining effluents. In each plot, three sediment cores were collected at 20 cm depth. Among the dominant mangrove species recorded were (in order of dominance): Sonneratia alba, Rhizophora stylosa, Avicennia marina, Excoecaria agallocha and Bruguiera gymnorrhiza. Sediment samples were digested with aqua regia, and the HM concentrations were quantified using Atomic Absorption Spectroscopy (AAS). Results showed that HM concentrations were higher in the vegetated plots as compared to the un-vegetated sites. Vegetated sites had high Ni (mean: 881.71 mg/kg) and Cr (mean: 776.36 mg/kg) that exceeded the threshold values (cf. by the United States Environmental Protection Agency; USEPA). Fe, Pb, Cu and Cd had a mean concentration of 2597.92 mg/kg, 40.94 mg/kg, 36.81 mg/kg and 2.22 mg/kg respectively. Vegetation variables were not significantly correlated with HM concentration. However, the HM concentration was significantly correlated with sediment variables particularly pH, redox, particle size, nitrogen, phosphorus, moisture and organic matter contents. The Pollution Load Index (PLI) indicated moderate to high pollution in the lake. Risk assessment and management should be designed in order to mitigate the ecological risk posed by HM. The need of a regular monitoring scheme for lake and mangrove rehabilitation programs and management should be designed.

Keywords: heavy metals, mangrove vegetation, mining, Philippines, sediment

Procedia PDF Downloads 160
3428 Investigation of Yard Seam Workings for the Proposed Newcastle Light Rail Project

Authors: David L. Knott, Robert Kingsland, Alistair Hitchon

Abstract:

The proposed Newcastle Light Rail is a key part of the revitalisation of Newcastle, NSW and will provide a frequent and reliable travel option throughout the city centre, running from Newcastle Interchange at Wickham to Pacific Park in Newcastle East, a total of 2.7 kilometers in length. Approximately one-third of the route, along Hunter and Scott Streets, is subject to potential shallow underground mine workings. The extent of mining and seams mined is unclear. Convicts mined the Yard Seam and overlying Dudley (Dirty) Seam in Newcastle sometime between 1800 and 1830. The Australian Agricultural Company mined the Yard Seam from about 1831 to the 1860s in the alignment area. The Yard Seam was about 3 feet (0.9m) thick, and therefore, known as the Yard Seam. Mine maps do not exist for the workings in the area of interest and it was unclear if both or just one seam was mined. Information from 1830s geological mapping and other data showing shaft locations were used along Scott Street and information from the 1908 Royal Commission was used along Hunter Street to develop an investigation program. In addition, mining was encountered for several sites to the south of the alignment at depths of about 7 m to 25 m. Based on the anticipated depths of mining, it was considered prudent to assess the potential for sinkhole development on the proposed alignment and realigned underground utilities and to obtain approval for the work from Subsidence Advisory NSW (SA NSW). The assessment consisted of a desktop study, followed by a subsurface investigation. Four boreholes were drilled along Scott Street and three boreholes were drilled along Hunter Street using HQ coring techniques in the rock. The placement of boreholes was complicated by the presence of utilities in the roadway and traffic constraints. All the boreholes encountered the Yard Seam, with conditions varying from unmined coal to an open void, indicating the presence of mining. The geotechnical information obtained from the boreholes was expanded by using various downhole techniques including; borehole camera, borehole sonar, and downhole geophysical logging. The camera provided views of the rock and helped to explain zones of no recovery. In addition, timber props within the void were observed. Borehole sonar was performed in the void and provided an indication of room size as well as the presence of timber props within the room. Downhole geophysical logging was performed in the boreholes to measure density, natural gamma, and borehole deviation. The data helped confirm that all the mining was in the Yard Seam and that the overlying Dudley Seam had been eroded in the past over much of the alignment. In summary, the assessment allowed the potential for sinkhole subsidence to be assessed and a mitigation approach developed to allow conditional approval by SA NSW. It also confirmed the presence of mining in the Yard Seam, the depth to the seam and mining conditions, and indicated that subsidence did not appear to have occurred in the past.

Keywords: downhole investigation techniques, drilling, mine subsidence, yard seam

Procedia PDF Downloads 314
3427 Constructing a Semi-Supervised Model for Network Intrusion Detection

Authors: Tigabu Dagne Akal

Abstract:

While advances in computer and communications technology have made the network ubiquitous, they have also rendered networked systems vulnerable to malicious attacks devised from a distance. These attacks or intrusions start with attackers infiltrating a network through a vulnerable host and then launching further attacks on the local network or Intranet. Nowadays, system administrators and network professionals can attempt to prevent such attacks by developing intrusion detection tools and systems using data mining technology. In this study, the experiments were conducted following the Knowledge Discovery in Database Process Model. The Knowledge Discovery in Database Process Model starts from selection of the datasets. The dataset used in this study has been taken from Massachusetts Institute of Technology Lincoln Laboratory. After taking the data, it has been pre-processed. The major pre-processing activities include fill in missed values, remove outliers; resolve inconsistencies, integration of data that contains both labelled and unlabelled datasets, dimensionality reduction, size reduction and data transformation activity like discretization tasks were done for this study. A total of 21,533 intrusion records are used for training the models. For validating the performance of the selected model a separate 3,397 records are used as a testing set. For building a predictive model for intrusion detection J48 decision tree and the Naïve Bayes algorithms have been tested as a classification approach for both with and without feature selection approaches. The model that was created using 10-fold cross validation using the J48 decision tree algorithm with the default parameter values showed the best classification accuracy. The model has a prediction accuracy of 96.11% on the training datasets and 93.2% on the test dataset to classify the new instances as normal, DOS, U2R, R2L and probe classes. The findings of this study have shown that the data mining methods generates interesting rules that are crucial for intrusion detection and prevention in the networking industry. Future research directions are forwarded to come up an applicable system in the area of the study.

Keywords: intrusion detection, data mining, computer science, data mining

Procedia PDF Downloads 297
3426 Hydrogeological Appraisal of Karacahisar Coal Field (Western Turkey): Impacts of Mining on Groundwater Resources Utilized for Water Supply

Authors: Sukran Acikel, Mehmet Ekmekci, Otgonbayar Namkhai

Abstract:

Lignite coal fields in western Turkey generally occurs in tensional Neogene basins bordered by major faults. Karacahisar coal field in Mugla province of western Turkey is a large Neogene basin filled with alternation of silisic and calcerous layers. The basement of the basin is composed of mainly karstified carbonate rocks of Mesozoic and schists of Paleozoic age. The basement rocks are exposed at highlands surrounding the basin. The basin fill deposits forms shallow, low yield and local aquifers whereas karstic carbonate rock masses forms the major aquifer in the region. The karstic aquifer discharges through a spring zone issuing at intersection of two major faults. Municipal water demand in Bodrum city, a touristic attraction area is almost totally supplied by boreholes tapping the karstic aquifer. A well field has been constructed on the eastern edge of the coal basin, which forms a ridge separating two Neogene basins. A major concern was raised about the plausible impact of mining activities on groundwater system in general and on water supply well field in particular. The hydrogeological studies carried out in the area revealed that the coal seam is located below the groundwater level. Mining operations will be affected by groundwater inflow to the pits, which will require dewatering measures. Dewatering activities in mine sites have two-sided effects: a) lowers the groundwater level at and around the pit for a safe and effective mining operation, b) continuous dewatering causes expansion of cone of depression to reach a spring, stream and/or well being utilized by local people, capturing their water. Plausible effect of mining operations on the flow of the spring zone was another issue of concern. Therefore, a detailed representative hydrogeological conceptual model of the site was developed on the basis of available data and field work. According to the hydrogeological conceptual model, dewatering of Neogene layers will not hydraulically affect the water supply wells, however, the ultimate perimeter of the open pit will expand to intersect the well field. According to the conceptual model, the coal seam is separated from the bottom by a thick impervious clay layer sitting on the carbonate basement. Therefore, the hydrostratigraphy does not allow a hydraulic interaction between the mine pit and the karstic carbonate rock aquifer. However, the structural setting in the basin suggests that deep faults intersecting the basement and the Neogene sequence will most probably carry the deep groundwater up to a level above the bottom of the pit. This will require taking necessary measure to lower the piezometric level of the carbonate rock aquifer along the faults. Dewatering the carbonate rock aquifer will reduce the flow to the spring zone. All findings were put together to recommend a strategy for safe and effective mining operation.

Keywords: conceptual model, dewatering, groundwater, mining operation

Procedia PDF Downloads 401
3425 Research on the Correlation between College Students' Physical Fitness and Running Habits: Data Mining of Smart Phone Sports App

Authors: Mingming Guo, Xiaozan Wang

Abstract:

Introduction: The purpose of this study is to examine the correlation between the physical fitness of Chinese college students and their daily running habits (RH). Methods: A total of 718 college students from East China Normal University participated in this study (385 boys and 333 girls). Each participant participated in the Chinese Students’ Physical Fitness Test during the 2018-2019 school year. In addition, each student is also required to use the app to record all their running results during each run during the 2018-2019 school year. Researchers can query and export all running records through the app's management platform. Results: (1) The total number of kilometers run by the students showed a significant negative correlation with their vital capacity (VC), sitting body flexion (SBF), and long jump (LJ) (rᵥ

Keywords: college students, physical fitness, running habits, data mining

Procedia PDF Downloads 141
3424 Association Analysis of Putative Loci with Coronary Artery Disease

Authors: Asma Naseer Cheema, Attya Bhatti, Jabar Ali, John Peter

Abstract:

Background: High cholesterol levels, endothelial dysfunction, inefficient coagulation cascade and hyper inflammatory response all are the basis of coronary artery disease (CAD). Several studies are carried out to see the genetic influence of these factors on disease outcome. Objective: The objective of our study was to see the association of 10 putative loci with coronary artery disease in our population. Materials & Methods: We screened our population for 10 putative loci of CAD showing significant association (p < 5x10-8) with candidate genes (regulating the cholesterol metabolism, endothelial function, coagulation cascade and inflammatory response of body). Hardy-Weinberg equilibrium and linkage disequilibrium in cases and controls s were estimated separately. Approximately 5-10 ng of dried DNA in 384 well plate format was used to genotype each sample on the Sequenom iPLEX assay at University of Pittsburgh Genomics and Proteomics Core Laboratories. It was built on single-base primer extension with the MALDI-TOF MS detection possessing high sensitivity and specificity. The SNPs were genotyped through Taqman assay. Hardy Weinberg test was applied. The 10 SNPs were selected as genetic markers for this study (rs579459, rs1561198, rs2954029, rs1122608, rs17114036, rs9515203, rs10947789, rs7173743, rs2895811, rs2075650). Results: Mean age of the patient was 52 ± 11 years. Blood pressure and positive family history was found a significant risk factor for CAD. None of the selected SNPs showed significant association with coronary artery disease in our population (p>0.05). Conclusion: rs579459, rs1561198, rs2954029, rs1122608, rs17114036, rs9515203, rs10947789, rs7173743, rs2895811, rs2075650 are not significant genetic markers for CAD in our population.

Keywords: CAD, genetic markers, loci, risk factors

Procedia PDF Downloads 371
3423 Effect of Spelling on Communicative Competence: A Case Study of Registry Staff of the University of Ibadan, Nigeria

Authors: Lukman Omobola Adisa

Abstract:

Spelling is rule bound in a written discourse. It, however, calls into question, when such convention is grossly contravened in a formal setting revered as citadel of learning, despite availability of computer spell-checker, human knowledge, and lexicon. The foregoing reveals the extent of decadence pervading education sector in Nigeria. It is on this premise that this study reviews the effect of spelling on communicative competence of the University of Ibadan Registry Staff. The theoretical framework basically evaluates diverse scholars’ views on communicative competence and how spelling influences the intended meaning of a word/ sentence as a result of undue infringement on grammatical (spelling) rule. Newsletter, bulletin, memo, and letter are four print materials purposively selected while the methodology adopted is content analysis. Similarly, five categories, though not limited to, through which spelling blunders are committed are considered: effect of spelling (omission, addition, and substitution); sound ( homophone); transposition (heading/body: content) and ambiguity (capitalisation, space, and acronym). Subsequently, the analyses, findings, and recommendations are equally looked into. Summarily, the study x-rays effective role(s) plays by spelling in enhancing communicative competence through appropriate usage of linguistic registers.

Keywords: communicative competence, content analysis, effect of spelling, linguistics registers

Procedia PDF Downloads 219
3422 Proteomic Evaluation of Sex Differences in the Plasma of Non-human Primates Exposed to Ionizing Radiation for Biomarker Discovery

Authors: Christina Williams, Mehari Weldemariam, Ann M. Farese, Thomas J. MacVittie, Maureen A. Kane

Abstract:

Radiation exposure results in dose-dependent and time-dependent multi-organ damage. Drug development of medical countermeasures (MCM) for radiation-induced injury occurs under the FDA Animal Rule because human efficacy studies are not ethical or feasible. The FDA Animal Rule requires the representation of both sexes and describes several uses for biomarkers in MCM drug development studies. Currently, MCMs are limited and there is no FDA-approved biomarker for any radiation injury. Sex as a variable is essential to identifying biomarkers and developing effective MCMs for acute radiation exposure (ARS) and delayed effects of acute radiation exposure (DEARE). These studies aim to address the death of information on sex differences that have not been determined by studies that included only male, single-sex cohorts. Studies have reported differences in radiosensitivity according to sex. As such, biomarker discovery for radiation-induced damage must consider sex as a variable. This study evaluated the plasma proteomic profile of Rhesus macaque non-human primates after different exposures and doses, as well as time points after radiation. Exposures and doses included total body irradiation between 5-7.5 Gy and partial body irradiation with 5% bone marrow sparing at 9, 9.5 and 10 Gy. Timepoints after irradiation included days 1, 3, 60, and 180, which encompassed both acute radiation syndromes and delayed effects of acute radiation exposure. Bottom-up proteomic analyses of plasma included equal numbers of males and females. In the control animals, few proteomic differences are observed between the sexes. In the irradiated animals, there are a few sex differences, with changes mostly consisting of proteins upregulated in the female animals. Multiple canonical pathways were upregulated in irradiated animals relative to the control animals when subjected to pathway analysis, but differential responses between the sexes are limited. These data provide critical baseline differences according to sex and establish sex differences in non-human primate models relevant to drug development of MCM under the FDA Animal Rule.

Keywords: ionizing radiation, sex differences, plasma proteomics, biomarker discovery

Procedia PDF Downloads 91
3421 The Association between Prior Antibiotic Use and Subsequent Risk of Infectious Disease: A Systematic Review

Authors: Umer Malik, David Armstrong, Mark Ashworth, Alex Dregan, Veline L'Esperance, Lucy McDonnell, Mariam Molokhia, Patrick White

Abstract:

Introduction: The microbiota lining epithelial surfaces is thought to play an important role in many human physiological functions including defense against pathogens and modulation of immune response. The microbiota is susceptible to disruption from external influences such as exposure to antibiotic medication. It is thought that antibiotic-induced disruption of the microbiota could predispose to pathogen overgrowth and invasion. We hypothesized that antibiotic use would be associated with increased risk of future infections. We carried out a systematic review of evidence of associations between antibiotic use and subsequent risk of community-acquired infections. Methods: We conducted a review of the literature for observational studies assessing the association between antibiotic use and subsequent community-acquired infection. Eligible studies were published before April 29th, 2016. We searched MEDLINE, EMBASE, and Web of Science and screened titles and abstracts using a predefined search strategy. Infections caused by Clostridium difficile, drug-resistant organisms and fungal organisms were excluded as their association with prior antibiotic use has been examined in previous systematic reviews. Results: Eighteen out of 21,518 retrieved studies met the inclusion criteria. The association between past antibiotic exposure and subsequent increased risk of infection was reported in 16 studies, including one study on Campylobacter jejuni infection (Odds Ratio [OR] 3.3), two on typhoid fever (ORs 5.7 and 12.2), one on Staphylococcus aureus skin infection (OR 2.9), one on invasive pneumococcal disease (OR 1.57), one on recurrent furunculosis (OR 16.6), one on recurrent boils and abscesses (Risk ratio 1.4), one on upper respiratory tract infection (OR 2.3) and urinary tract infection (OR 1.1), one on invasive Haemophilus influenzae type b (Hib) infection (OR 1.51), one on infectious mastitis (OR 5.38), one on meningitis (OR 2.04) and five on Salmonella enteric infection (ORs 1.4, 1.59, 1.9, 2.3 and 3.8). The effect size in three studies on Salmonella enteric infection was of marginal statistical significance. A further two studies on Salmonella infection did not demonstrate a statistically significant association between prior antibiotic exposure and subsequent infection. Conclusion: We have found an association between past antibiotic exposure and subsequent risk of a diverse range of infections in the community setting. Our findings provide evidence to support the hypothesis that prior antibiotic usage may predispose to future infection risk, possibly through antibiotic-induced alteration of the microbiota. The findings add further weight to calls to minimize inappropriate antibiotic prescriptions.

Keywords: antibiotic, infection, risk factor, side effect

Procedia PDF Downloads 227