Search results for: bone fracture risk
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 7201

Search results for: bone fracture risk

6091 Establishment of a Nomogram Prediction Model for Postpartum Hemorrhage during Vaginal Delivery

Authors: Yinglisong, Jingge Chen, Jingxuan Chen, Yan Wang, Hui Huang, Jing Zhnag, Qianqian Zhang, Zhenzhen Zhang, Ji Zhang

Abstract:

Purpose: The study aims to establish a nomogram prediction model for postpartum hemorrhage (PPH) in vaginal delivery. Patients and Methods: Clinical data were retrospectively collected from vaginal delivery patients admitted to a hospital in Zhengzhou, China, from June 1, 2022 - October 31, 2022. Univariate and multivariate logistic regression were used to filter out independent risk factors. A nomogram model was established for PPH in vaginal delivery based on the risk factors coefficient. Bootstrapping was used for internal validation. To assess discrimination and calibration, receiver operator characteristics (ROC) and calibration curves were generated in the derivation and validation groups. Results: A total of 1340 cases of vaginal delivery were enrolled, with 81 (6.04%) having PPH. Logistic regression indicated that history of uterine surgery, induction of labor, duration of first labor, neonatal weight, WBC value (during the first stage of labor), and cervical lacerations were all independent risk factors of hemorrhage (P <0.05). The area-under-curve (AUC) of ROC curves of the derivation group and the validation group were 0.817 and 0.821, respectively, indicating good discrimination. Two calibration curves showed that nomogram prediction and practical results were highly consistent (P = 0.105, P = 0.113). Conclusion: The developed individualized risk prediction nomogram model can assist midwives in recognizing and diagnosing high-risk groups of PPH and initiating early warning to reduce PPH incidence.

Keywords: vaginal delivery, postpartum hemorrhage, risk factor, nomogram

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6090 External Validation of Risk Prediction Score for Candidemia in Critically Ill Patients: A Retrospective Observational Study

Authors: Nurul Mazni Abdullah, Saw Kian Cheah, Raha Abdul Rahman, Qurratu 'Aini Musthafa

Abstract:

Purpose: Candidemia was associated with high mortality in the critically ill patients. Early candidemia prediction is imperative for preemptive antifungal treatment. This study aimed to externally validate the candidemia risk prediction scores by Jameran et al. (2021) by identifying risk factors of acute kidney injury, renal replacement therapy, parenteral nutrition, and multifocal candida colonization. Methods: This single-center, retrospective observational study included all critically ill patients admitted to the intensive care unit (ICU) in a tertiary referral center from January 2018 to December 2023. The study evaluated the candidemia risk prediction score performance by analysing the occurrence of candidemia within the study period. Patients’ demographic characteristics, comorbidities, SOFA scores, and ICU outcomes were analyzed. Patients who were diagnosed with candidemia prior to ICU admission were excluded. Results: A total of 500 patients were analyzed with 2 dropouts due to incomplete data. Validation analysis showed that the candidemia risk prediction score has a sensitivity of 75.00% (95% CI: 59.66-86.81), specificity of 65.35% (95% CI: 60.78-69.72), positive predictive value of 17.28, and negative predictive value of 96.44. The incidence of candidemia was 8.86%, with no significant differences in demographics or comorbidities except for higher SOFA scoring in the candidemia group. The candidemia group showed significantly longer ICU, hospital LOS, and higher ICU in-hospital mortality. Conclusion: This study concluded the candidemia risk prediction score by Jameran et al. (2021) had good sensitivity and a high negative prediction value. Thus, the risk prediction score was validated for candidemia prediction in critically ill patients.

Keywords: Candidemia, intensive care, acute kidney injury, clinical prediction rule, incidence

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6089 Biodiversity Affects Bovine Tuberculosis (bTB) Risk in Ethiopian Cattle: Prospects for Infectious Disease Control

Authors: Sintayehu W. Dejene, Ignas M. A. Heitkönig, Herbert H. T. Prins, Zewdu K. Tessema, Willem F. de Boer

Abstract:

Current theories on diversity-disease relationships describe host species diversity and species identity as important factors influencing disease risk, either diluting or amplifying disease prevalence in a community. Whereas the simple term ‘diversity’ embodies a set of animal community characteristics, it is not clear how different measures of species diversity are correlated with disease risk. We, therefore, tested the effects of species richness, Pielou’s evenness and Shannon’s diversity on bTB risk in cattle in the Afar Region and Awash National Park between November 2013 and April 2015. We also analysed the identity effect of a particular species and the effect of host habitat use overlap on bTB risk. We used the comparative intradermal tuberculin test to assess the number of bTB infected cattle. Our results suggested a dilution effect through species evenness. We found that the identity effect of greater kudu - a maintenance host – confounded the dilution effect of species diversity on bTB risk. bTB infection was positively correlated with habitat use overlap between greater kudu and cattle. Different diversity indices have to be considered together for assessing diversity-disease relationships, for understanding the underlying causal mechanisms. We posit that unpacking diversity metrics is also relevant for formulating control strategies to manage cattle in ecosystems characterized by seasonally limited resources and intense wildlife-livestock interactions.

Keywords: evenness, diversity, greater kudu, identity effect, maintenance hosts, multi-host disease ecology, habitat use overlap

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6088 Machine Learning Analysis of Eating Disorders Risk, Physical Activity and Psychological Factors in Adolescents: A Community Sample Study

Authors: Marc Toutain, Pascale Leconte, Antoine Gauthier

Abstract:

Introduction: Eating Disorders (ED), such as anorexia, bulimia, and binge eating, are psychiatric illnesses that mostly affect young people. The main symptoms concern eating (restriction, excessive food intake) and weight control behaviors (laxatives, vomiting). Psychological comorbidities (depression, executive function disorders, etc.) and problematic behaviors toward physical activity (PA) are commonly associated with ED. Acquaintances on ED risk factors are still lacking, and more community sample studies are needed to improve prevention and early detection. To our knowledge, studies are needed to specifically investigate the link between ED risk level, PA, and psychological risk factors in a community sample of adolescents. The aim of this study is to assess the relation between ED risk level, exercise (type, frequency, and motivations for engaging in exercise), and psychological factors based on the Jacobi risk factors model. We suppose that a high risk of ED will be associated with the practice of high caloric cost PA, motivations oriented to weight and shape control, and psychological disturbances. Method: An online survey destined for students has been sent to several middle schools and colleges in northwest France. This survey combined several questionnaires, the Eating Attitude Test-26 assessing ED risk; the Exercise Motivation Inventory–2 assessing motivations toward PA; the Hospital Anxiety and Depression Scale assessing anxiety and depression, the Contour Drawing Rating Scale; and the Body Esteem Scale assessing body dissatisfaction, Rosenberg Self-esteem Scale assessing self-esteem, the Exercise Dependence Scale-Revised assessing PA dependence, the Multidimensional Assessment of Interoceptive Awareness assessing interoceptive awareness and the Frost Multidimensional Perfectionism Scale assessing perfectionism. Machine learning analysis will be performed in order to constitute groups with a tree-based model clustering method, extract risk profile(s) with a bootstrap method comparison, and predict ED risk with a prediction method based on a decision tree-based model. Expected results: 1044 complete records have already been collected, and the survey will be closed at the end of May 2022. Records will be analyzed with a clustering method and a bootstrap method in order to reveal risk profile(s). Furthermore, a predictive tree decision method will be done to extract an accurate predictive model of ED risk. This analysis will confirm typical main risk factors and will give more data on presumed strong risk factors such as exercise motivations and interoceptive deficit. Furthermore, it will enlighten particular risk profiles with a strong level of proof and greatly contribute to improving the early detection of ED and contribute to a better understanding of ED risk factors.

Keywords: eating disorders, risk factors, physical activity, machine learning

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6087 Serum Granulocyte Colony Stimulating Factor is a Potent Stimulator of Hematopoeitic Progenitor Cells Mobilization in Trauma Hemorrhagic Shock

Authors: Manoj Kumar, Sujata Mohanty, D. N. Rao, Arul Selvi, Sanjeev K. Bhoi

Abstract:

Background: Hematopoietic progenitor cells (HPC) mobilized from bone marrow to peripheral blood has been observed in severe trauma and hemorrhagic shock patients. Granulocyte-colony stimulating factor (G-CSF) is a potent stimulator that mobilized HPC from bone marrow to peripheral blood. Objective: Our aim of the study was to investigate the serum G-CSF levels and correlate with HPC and outcome. Methods: Peripheral blood sample from 50 hemorrhagic shock patients was collected on arrival for determination of G-CSF and peripheral blood HPC (PBHPC) and compared with healthy control (n=15). Determination of serum levels of G-CSF by sandwich ELISA and PBHPC by Sysmex XE-2100. Data were categorized by age, sex, Injury Severity Score (ISS), and laboratory data was prospectively collected. Data are expressed as mean±SD and median (min, max). Results: Significantly increased the serum level of G-CSF (264.8 vs. 79.1 pg/ml) and peripheral blood HPC (0.1 vs. 0.01 %) in the T/HS patients when compared with control group. Conclusions: Our studies suggest serum G-CSF elevated in T/HS patients. The elevated in G-CSF was also associated with mobilization of HPC from BM to peripheral blood HPC. Increased the levels of G-CSF in T/HS may play a significant role in the alteration of the hematopoietic compartment.

Keywords: granulocyte colony stimulating factor, G-CSF, hematopoietic progenitor cells, HPC, trauma hemorrhagic shock, T/HS, outcome

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6086 Risking Injury: Exploring the Relationship between Risk Propensity and Injuries among an Australian Rules Football Team

Authors: Sarah A. Harris, Fleur L. McIntyre, Paola T. Chivers, Benjamin G. Piggott, Fiona H. Farringdon

Abstract:

Australian Rules Football (ARF) is an invasion based, contact field sport with over one million participants. The contact nature of the game increases exposure to all injuries, including head trauma. Evidence suggests that both concussion and sub-concussive traumas such as head knocks may damage the brain, in particular the prefrontal cortex. The prefrontal cortex may not reach full maturity until a person is in their early twenties with males taking longer to mature than females. Repeated trauma to the pre-frontal cortex during maturation may lead to negative social, cognitive and emotional effects. It is also during this period that males exhibit high levels of risk taking behaviours. Risk propensity and the incidence of injury is an unexplored area of research. Little research has considered if the level of player’s (especially younger players) risk propensity in everyday life places them at an increased risk of injury. Hence the current study, investigated if a relationship exists between risk propensity and self-reported injuries including diagnosed concussion and head knocks, among male ARF players aged 18 to 31 years. Method: The study was conducted over 22 weeks with one West Australian Football League (WAFL) club during the 2015 competition. Pre-season risk propensity was measured using the 7-item self-report Risk Propensity Scale. Possible scores ranged from 9 to 63, with higher scores indicating higher risk propensity. Players reported their self-perceived injuries (concussion, head knocks, upper body and lower body injuries) fortnightly using the WAFL Injury Report Survey (WIRS). A unique ID code was used to ensure player anonymity, which also enabled linkage of survey responses and injury data tracking over the season. A General Linear Model (GLM) was used to analyse whether there was a relationship between risk propensity score and total number of injuries for each injury type. Results: Seventy one players (N=71) with an age range of 18.40 to 30.48 years and a mean age of 21.92 years (±2.96 years) participated in the study. Player’s mean risk propensity score was 32.73, SD ±8.38. Four hundred and ninety five (495) injuries were reported. The most frequently reported injury was head knocks representing 39.19% of total reported injuries. The GLM identified a significant relationship between risk propensity and head knocks (F=4.17, p=.046). No other injury types were significantly related to risk propensity. Discussion: A positive relationship between risk propensity and head trauma in contact sports (specifically WAFL) was discovered. Assessing player’s risk propensity therefore, may identify those more at risk of head injuries. Potentially leading to greater monitoring and education of these players throughout the season, regarding self-identification of head knocks and symptoms that may indicate trauma to the brain. This is important because many players involved in WAFL are in their late teens or early 20’s hence, may be at greater risk of negative outcomes if they experience repeated head trauma. Continued education and research into the risks associated with head injuries has the potential to improve player well-being.

Keywords: football, head injuries, injury identification, risk

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6085 Histopathological and Biochemical Evaluation of Hydroxyurea-Induced Hepato-Pulmonary Toxicity and Lymphoid Necrosis in Rats

Authors: Samah Oda, Asmaa Khafaga, Mohammed Hashim, Asmaa Khamis

Abstract:

Toxicity of hydroxyurea (HU), a treatment for certain tumors, polycythemia, and thrombocytosis, was evaluated in rats in one-month toxicity study. Sixty male albino rats were equally classified into four groups. Rats received daily oral gavage of HU in 0, 250, 500, and 750 mg/kg b.wt. Chemical and histopathological assessment of liver, lung, spleen, and bone marrow was performed at 10, 20, and 30 days of the experiment. No significant change was reported in alanine aminotransferase (ALT), aspartate aminotransferase (AST), globulin, and albumin/ globulin ratio during the experiment. Significant decreases in alkaline phosphatase (ALP) and total albumin were reported in rats received 500 and 750 mg/kg b.wt of HU. In addition, total cholesterol level increased significantly after 10 days; however, it significantly decreased after 20 and 30 days of the experiment. Moreover, hepatocytic vacuolation and necrosis with portal inflammatory infiltrates were reported along experimental periods. Pulmonary congestion, hemorrhage, interstitial mononuclear infiltration, peribronchitis, and bronchial epithelial necrosis were also reported. Severe lymphocytic necrosis in spleen and severe loss of hematopoietic cells and replacement with corresponding adipose tissue in bone marrow tissues was demonstrated. In conclusion, HU could be able to induce severe dose and time-dependent hepato-pulmonary toxicity and lymphoid depression in rats.

Keywords: hydroxyurea, hepato-pulmonary toxicity, lymphoid depression, histopathology

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6084 Climate Risk Perception and Trust – Presence of a Social Trap for Willingness to Act in Favour of Climate Mitigation and Support for Renewables: A Cross-sectional Study of Four European Countries

Authors: Lana Singleton

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Achieving a sufficient global solution to climate change seems elusive through disappointing climate agreements and lack of cooperation. However, is this reluctance of coordination deep rooted on a more individual, societal level within countries due to a fundamental lack of social and institutional trust? The risks of climate change are illustrious and widely accepted, yet responses on an individual level are also largely inadequate. This research looks to further investigate types of trust, risk perception of climate change, and their interaction to build a greater understanding of whether a social trap (Rothstein, 2005) – where an absence of trust can overwhelm an individuals’ risk perception and result in minimal action despite knowing the dangers of no action – exists and where it is more prevalent. Presence of the social trap will be analysed for willingness to act in favour of climate change mitigation as well as attitude (acceptance) of different types of renewable energy forms. Using probit models with cross-sectional survey data on four developed European countries (UK, France, Germany, and Norway), we find evidence of the social trap in the aggregated data model, which highlights the importance of social trust regarding willingness to act in favour of climate mitigation as there is a high probability of action regardless of risk perception of climate change when social trust is high. In contrast, the same is not true for renewables, as interactions were mainly insignificant, although there were interesting findings involving institutional trust, gender, and country specific results for particular renewables.

Keywords: climate risk, renewables, risk perception, social trap, trust, willingness to act

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6083 Landslide Hazard Zonation and Risk Studies Using Multi-Criteria Decision-Making and Slope Stability Analysis

Authors: Ankit Tyagi, Reet Kamal Tiwari, Naveen James

Abstract:

In India, landslides are the most frequently occurring disaster in the regions of the Himalayas and the Western Ghats. The steep slopes and land use in these areas are quite apprehensive. In the recent past, many landslide hazard zonation (LHZ) works have been carried out in the Himalayas. However, the preparation of LHZ maps considering temporal factors such as seismic ground shaking, seismic amplification at surface level, and rainfall are limited. Hence this study presents a comprehensive use of the multi-criteria decision-making (MCDM) method in landslide risk assessment. In this research, we conducted both geospatial and geotechnical analysis to minimize the danger of landslides. Geospatial analysis is performed using high-resolution satellite data to produce landslide causative factors which were given weightage using the MCDM method. The geotechnical analysis includes a slope stability check, which was done to determine the potential landslide slope. The landslide risk map can provide useful information which helps people to understand the risk of living in an area.

Keywords: landslide hazard zonation, PHA, AHP, GIS

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6082 The Descending Genicular Artery Perforator Free Flap as a Reliable Flap: Literature Review

Authors: Doran C. Kalmin

Abstract:

The descending genicular artery (DGA) perforator free flap provides an alternative to free flap reconstruction based on a review of the literature detailing both anatomical and clinical studies. The descending genicular artery (DGA) supplies skin, muscle, tendon, and bone located around the medial aspect of the knee that has been used in several pioneering reports in reconstructing defects located in various areas throughout the body. After the success of the medial femoral condyle flap in early studies, a small number of studies have been published detailing the use of the DGA in free flap reconstruction. Despite early success in the use of the DGA flap, acceptance within the Plastic and Reconstructive Surgical community has been limited due primarily to anatomical variations of the pedicle. This literature review is aimed at detailing the progression of the DGA perforator free flap and its variations as an alternative and reliable free flap for reconstruction of composite defects with an exploration into both anatomical and clinical studies. A literature review was undertaken, and the progression of the DGA flap is explored from the early review by Acland et al. pioneering the saphenous free flap to exploring modern changes and studies of the anatomy of the DGA. An extensive review of the literature was undertaken that details the anatomy and its variations, approaches to harvesting the flap, the advantages, and disadvantages of the DGA perforator free flap as well as flap outcomes. There are 15 published clinical series of DGA perforator free flaps that incorporate cutaneous, osteoperiosteal, cartilage, osteocutaneous, osteoperiosteal and muscle, osteoperiosteal and subcutaneous and tendocutatenous. The commonest indication for using a DGA free flap was for non-union of bone, particularly that of the scaphoid whereby the medial femoral condyle could be used. In the case series, a success rate of over 90% was established, showing that these early studies have had good success with a wide range of tissue transfers. The greatest limitation is the anatomical variation of the DGA and therefore, the challenges associated with raising the flap. Despite the variation in anatomy and around 10-15% absence of the DGA, the saphenous artery can be used as well as the superior medial genicular artery if the vascular bone is required as part of the flap. Despite only a handful of anatomical and clinical studies describing the DGA perforator free flap, it ultimately provides a reliable flap that can include a variety of composite structure used for reconstruction in almost any area throughout the body. Although it has limitations, it provides a reliable option for free flap reconstruction that can routinely be performed as a single-stage procedure.

Keywords: anatomical study, clinical study, descending genicular artery, literature review, perforator free flap reconstruction

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6081 The Impacts of the Sit-Stand Workplace Intervention on Cardiometabolic Risk

Authors: Rebecca M. Dagger, Katy Hadgraft, Matthew Teggart, Peter Angell

Abstract:

Background: There is a growing body of evidence that demonstrates the association between sedentary behaviour, cardiometabolic risk and all-cause mortality. Since full time working adults spend approximately 8 hours per day in the workplace, interventions to reduce sedentary behaviour at work may alleviate some of the negative health outcomes associated with sedentary behaviour. The aims of this pilot study were to assess the impacts of using a Sit-Stand workstation on markers of cardiometabolic health in a cohort of desk workers. Methods: Twenty eight participants were recruited and randomly assigned to a control (n=5 males, 9 females, mean age 37 years ± 9.4 years) or intervention group (n= 5 males, 9 females, mean age 42 years ± 12.7 years). All participants attended the labs on 2 occasion’s pre and post intervention, following baseline measurements the intervention participants had the Sit Stand Workstations (Ergotron, USA) installed for a 10 week intervention period. The Sit Stand workstations allow participants to stand or sit at their usual workstation and participants were encouraged to the use the desk in a standing position at regular intervals throughout the working day. Cardiometabolic risk markers assessed were body mass, body composition (using bio impedance analysis; Tanita, Tokyo), fasting blood Total Cholesterol (TC), lipid profiles (HDL-C, LDL-C, TC: HDL-C ratio), triglycerides and fasting glucose (Cholestech LDX), resting systolic and diastolic blood pressure and resting heart rate. ANCOVA controlling for baseline values was used to assess the group difference in changes in risk markers between pre and post intervention. Results: The 10 week intervention was associated with significant reductions in some cardiometabolic risk factors. There were significant group effects on change in body mass (F (1,25)=5.915, p<0.05), total body fat percentage (F(1,25)=12.615, p<0.01), total fat mass (F (1,25)=6.954, p<0.05), and systolic blood pressure (F (1,25)=5.012, p<0.05). There were no other significant group effects on changes in other cardiometabolic risk markers. Conclusion: This pilot study highlights the importance of reducing sedentary behaviour in the workplace for reduction in cardiometabolic risk markers. Further research is required to support these findings.

Keywords: sedentary behaviour, caridometabolic risk, evidence, risk makers

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6080 Prevalence Of High-Risk Obstructive Sleep Apnoea by Berlin Questionnaire in Patients with Type 2 Diabetes Mellitus: A Study from Tertiary Care Hospital

Authors: Leela Lakshmi Sai Srinivas Parasa, Pushpavalli Naidu, Bhaskar Kambhampati

Abstract:

Background: Obstructive Sleep Apnea (OSA) is a common but underdiagnosed sleep disorder characterized by repeated upper airway collapse during sleep. It frequently coexists with Type 2 Diabetes Mellitus (T2DM), a chronic metabolic condition with significant global and national health implications. The interplay between these conditions increases the risk of severe complications such as stroke, hypertension, and cardiovascular diseases. Understanding the prevalence of high-risk OSA in T2DM patients is essential for improving clinical outcomes and guiding public health interventions. Objective: This study aimed to assess the prevalence of high-risk OSA among T2DM patients using the Berlin questionnaire and to identify demographic and clinical predictors of risk. Methodology: This cross-sectional study of 100 patients with Type2 diabetes was undertaken at a tertiary care hospital in India for a period of 2 months. OSA was evaluated using the Berlin questionnaire. Diabetes mellitus was diagnosed according to WHO criteria as fasting blood sugar level > 7 mmol/L or random blood sugar >126 mg/dl on 2 separate occasions. Particulars of patients were recorded following which detailed history and physical examination were done. Data was analyzed using spss version 21. Results: The prevalence of high-risk OSA was 72% among the study population. The mean age was 54.9 +- 12.47 years. Age groups were divided into 3 groups (less than 50, 50-65, and greater than 65) The highest prevalence was observed in the 50-65 age group, accounting for 59.7% of high-risk cases. Gender distribution revealed a higher proportion of high-risk females (88.46%) compared to males (66.21%). Normal-weight individuals (BMI 18.5–24.9 kg/m²) represented 74.02% of high-risk OSA cases, while overweight individuals (BMI 25–29.9 kg/m²) accounted for 65.21%. Additionally, 90.9% of hypertensive patients were identified as high-risk for OSA. Conclusion: The study highlights a high prevalence of OSA risk among T2DM patients, especially those with hypertension and those in the middle-aged group. These findings emphasize the importance of routine OSA screening and tailored interventions for diabetic patients to reduce associated health risks. Proactive management can help mitigate the compounded effects of these two conditions, improving overall patient outcomes and reducing the burden on healthcare systems.

Keywords: obstructive sleep apnea, type 2 diabetes mellitus, berlin questionnaire, prevalence, hypertension

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6079 Relation of Cad/Cam Zirconia Dental Implant Abutments with Periodontal Health and Final Aesthetic Aspects; A Systematic Review

Authors: Amin Davoudi

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Aim: New approaches have been introduced to improve soft tissue indices of the dental implants. This systematic review aimed to investigate the effect of computer-aided design and computer-assisted manufacture (CAD/CAM) zirconia (Zr) implant abutments on periodontal aspects. Materials and Methods: Five electronic databases were searched thoroughly based on prior defined MeSH and non-MeSH keywords. Clinical studies were collected via hand searches in English language journals up to September 2020. Interproximal papilla stability, papilla recession, pink and white esthetic score (PES, WES), bone and gingival margin levels, color, and contour of soft tissue were reviewed. Results: The initial literature search yielded 412 articles. After the evaluation of abstracts and full texts, six studies were eligible to be screened. The study design of the included studies was a prospective cohort (n=3) and randomized clinical trial (n=3). The outcome was found to be significantly better for Zr than titanium abutments, however, the studies did not show significant differences between stock and CAD/CAM abutments. Conclusion: Papilla fill, WES, PES, and the distance from the contact point to dental crest bone of adjacent tooth and inter-tooth–implant distance were not significantly different between Zr CAD/CAM and Zr stock abutments. However, soft tissue stability and recession index were better in Zr CAD/CAM abutments.

Keywords: zirconia, CADCAM, periodental, implant

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6078 Ecological and Health Risk Assessment of the Heavy Metal Contaminant in Surface Soils around Effurun Market

Authors: A. O. Ogunkeyede, D. Amuchi, A. A. Adebayo

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Heavy metal contaminations in soil have received great attention. Anthropogenic activities such as vehicular emission, industrial activities and constructions have resulted in elevated concentration of heavy metals in the surface soils. The metal particles can be free from the surface soil when they are disturbed and re-entrained in air, which necessitated the need to investigate surface soil at market environment where adults and children are present on daily basis. This study assesses concentration of heavy metal pollution, ecological and health risk factors in surface soil at Effurun market. 8 samples were collected at household material (EMH), fish (EMFs), fish and commodities (EMF-C), Abattoir (EMA 1 & 2), fruit sections (EMF 1 & 2) and lastly main road (EMMR). The samples were digested and analyzed in triplicate for contents of Lead (Pb), Nickel (Ni), Cadmium (Cd) and Copper (Cu). The mean concentration of the Pb mg/kg (112.27 ± 1.12) and Cu mg/kg (156.14 ± 1.10) were highest in the abattoir section (EMA 1). The mean concentrations of the heavy metal were then used to calculate the ecological and health risk for people within the market. Pb contamination at EMMR, EMF 2, EMFs were moderately while Pb shows considerable contamination at EMH, EMA 1, EMA 2 and EMF-C sections of the Effurun market. The ecological risk factor varies between low to moderate pollution for Pb and EMA 1 has the highest potential ecological risk that falls within moderate pollution. The hazard quotient results show that dermal exposure pathway is the possible means of heavy metal exposure to the traders while ingestion is the least sources of exposure to adult. The ingestion suggested that children around the EMA 1 have the highest possible exposure to children due to hand-to-mouth and object-to-mouth behaviour. The results further show that adults at the EMA1 will have the highest exposure to Pb due to inhalation during burning of cow with tyre that contained Pb and Cu. The carcinogenic risk values of most sections were higher than acceptable values, while Ni at EMMR, EMF 1 & 2, EMFs and EMF-C sections that were below the acceptable values. The cancer risk for inhalation exposure pathway for Pb (1.01E+17) shows a significant level of contamination than all the other sections of the market. It suggested that the people working at the Abattoir were very prone to cancer risk.

Keywords: carcinogenic, ecological, heavy metal, risk

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6077 An Inherent Risk to Damage the Popliteus Tendon by Some Femoral Component Designs: A Pilot Study in Indian Knees

Authors: Rajendra Kanojia

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Femoral components with inbuilt rotation require thicker flexion resection of the lateral femoral condyle and could potential risk to damage the popliteus tendon especially in the smaller Asian knees. We prospectively evaluated 10 patients with bilateral varus osteoarthritis knee to size the cuts and their location in relation to the popliteus tendon. Two different types of implant were used on either side, one side requires resection in 3° external rotation (group A) and other side femoral component with inbuilt external roation (group B). We had popliteus tendon injury in 3 knees all from group B. Risk of damaging the popliteus tendon was found higher in group B.

Keywords: popliteaus tendon injury, TKA, orthopaedic surgery, biomechanics and clinical applications

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6076 Multiaxial Fatigue in Thermal Elastohydrodynamic Lubricated Contacts with Asperities and Slip

Authors: Carl-Magnus Everitt, Bo Alfredsson

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Contact mechanics and tribology have been combined with fundamental fatigue and fracture mechanics to form the asperity mechanism which supplies an explanation for the surface-initiated rolling contact fatigue damage, called pitting or spalling. The cracks causing the pits initiates at one surface point and thereafter they slowly grow into the material before chipping of a material piece to form the pit. In the current study, the lubrication aspects on fatigue initiation are simulated by passing a single asperity through a thermal elastohydrodynamic lubricated, TEHL, contact. The physics of the lubricant was described with Reynolds equation and the lubricants pressure-viscosity relation was modeled by Roelands equation, formulated to include temperature dependence. A pressure dependent shear limit was incorporated. To capture the full phenomena of the sliding contact the temperature field was resolved through the incorporation of the energy flow. The heat was mainly generated due to shearing of the lubricant and from dry friction where metal contact occurred. The heat was then transported, and conducted, away by the solids and the lubricant. The fatigue damage caused by the asperities was evaluated through Findley’s fatigue criterion. The results show that asperities, in the size of surface roughness found in applications, may cause surface initiated fatigue damage and crack initiation. The simulations also show that the asperities broke through the lubricant in the inlet, causing metal to metal contact with high friction. When the asperities thereafter moved through the contact, the sliding provided the asperities with lubricant releasing the metal contact. The release of metal contact was possible due to the high viscosity the lubricant obtained from the high pressure. The metal contact in the inlet caused higher friction which increased the risk of fatigue damage. Since the metal contact occurred in the inlet it increased the fatigue risk more for asperities subjected to negative slip than positive slip. Therefore the fatigue evaluations showed that the asperities subjected to negative slip yielded higher fatigue stresses than the asperities subjected to positive slip of equal magnitude. This is one explanation for why pitting is more common in the dedendum than the addendum on pinion gear teeth. The simulations produced further validation for the asperity mechanism by showing that asperities cause surface initiated fatigue and crack initiation.

Keywords: fatigue, rolling, sliding, thermal elastohydrodynamic

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6075 Impact of Lobular Carcinoma in situ on Local Recurrence in Breast Cancer Treated with Breast Conservation Therapy: A Systematic Review and Meta-Analysis

Authors: Christopher G. Harris, Guy D. Eslick

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Purpose: Lobular carcinoma in situ (LCIS) is a known risk factor for breast cancer of unclear significance when detected in association with invasive carcinoma. This meta-analysis aims to determine the impact of LCIS on local recurrence risk for individuals with breast cancer treated with breast conservation therapy to help guide appropriate treatment strategies. Methods: We identified relevant studies from five electronic databases. Studies were deemed suitable for inclusion where they compared patients with invasive breast cancer and concurrent LCIS to those with breast cancer alone, all patients underwent breast conservation therapy (lumpectomy with adjuvant radiation therapy), and local recurrence was evaluated. Recurrence data were pooled by use of a random effects model. Results: From 1488 citations screened by our search, 8 studies were deemed suitable for inclusion. These studies comprised of 908 cases and 10638 controls. Median follow-up time was 90 months. There was a significantly increased overall risk of local breast cancer recurrence for individuals with LCIS in association with breast cancer following breast conservation therapy [pOR 1.87; 95% CI 1.14-3.04; p = 0.012]. The risk of local recurrence was non-significantly increased at 5 [pOR 1.09; 95% CI 0.48-2.48; p = 0.828] and 10 years [pOR 1.90; 95% CI 0.89-4.06; p = 0.096]. Conclusions: Individuals with LCIS in association with invasive breast cancer have an increased risk of local recurrence following breast conservation therapy. This supports consideration of aggressive local control of LCIS by way of completion mastectomy or re-excision for certain high-risk patients.

Keywords: breast cancer, breast conservation therapy, lobular carcinoma in situ, lobular neoplasia, local recurrence, meta-analysis

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6074 Anemia Maternal in Pregnancy as a Risk Factor of Low Birth Weight: A Systematic Review

Authors: Herlena Hayati, Diyan Reni Jayathi, Hairida Anggun, Citra Amelia

Abstract:

This systematic review research is aimed to find out anemia maternal during pregnancy as a risk factor of low birth weight. This research was done by searching some journals which have associated to maternal anemia during pregnancy with low birth weight that had been published in journal accreditation and scopus index. Study literature that researcher had been done by March – April 2016 through online library of UI. The journals that had been selected according to inclusive criteria and exclusive criteria had been through the critial appraisal process. This systematic review towards 4 journals that had been selected and published showed the significant result statistically that anemia maternal is one of the risk factors which causes low birth weight. Anemia maternal on the first-trimester pregnancy showed significant association with low birth weight. Moderate anemia and severe anemia also showed significant association with low birth weight. Meanwhile, mild anemia doesn’t have an association with low birth weight. The conclusion of this study is anemia maternal (as an independent risk factor) have an influence towards low birth weight.

Keywords: anemia maternal, low birth weight, pregnancy, systematic review

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6073 The Conditionality of Financial Risk: A Comparative Analysis of High-Tech and Utility Companies Listed on the Shenzhen Stock Exchange (SSE)

Authors: Joseph Paul Chunga

Abstract:

The investment universe is awash with a myriad of financial choices that investors have to opt for, which principally culminates into a duality between aggressive or conservative approaches. Howbeit, it is pertinent to emphasize that the investment vehicles with an aggressive approach tend to take on more risk than the latter group in an effort to generate higher future returns for their respective investors. This study examines the conditionality effect that such partiality in financing has on the High-Tech and Public Utility companies listed on the Shenzhen Stock Exchange (SSE). Specifically, it examines the significance of the relationship between capitalization ratios of Total Debt Ratio (TDR), Degree of Financial Leverage (DFL) and profitability ratios of Earnings per Share (EPS) and Returns on Equity (ROE) on the Financial Risk of the two industries. We employ a modified version of the Panel Regression Model used by Rahman (2017) to estimate the relationship. The study finds that there is a significant positive relationship between the capitalization ratios on the financial risk of Public Utility companies more than High-Tech companies and a substantial negative relationship between the profitability ratios and the financial risk of the former than the latter companies. This then spells an important insight for prospective investors with regards to the volatility of earnings of such companies.

Keywords: financial leverage, debt financing, conservative firms, aggressive firms

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6072 Bacterial Cellulose/Silver-Doped Hydroxyapatite Composites for Tissue Engineering Application

Authors: Adrian Ionut Nicoara, Denisa Ionela Ene, Alina Maria Holban, Cristina Busuioc

Abstract:

At present, the development of materials with biomedical applications is a domain of interest that will produce a full series of benefits in engineering and medicine. In this sense, it is required to use a natural material, and this paper is focused on the development of a composite material based on bacterial cellulose – hydroxyapatite and silver nanoparticles with applications in hard tissue. Bacterial cellulose own features like biocompatibility, non-toxicity character and flexibility. Moreover, the bacterial cellulose can be conjugated with different forms of active silver to possess antimicrobial activity. Hydroxyapatite is well known that can mimic at a significant level the activity of the initial bone. The material was synthesized by using an ultrasound probe and finally characterized by several methods. Thereby, the morphological properties were analyzed by using Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM). Because the synthesized material has medical application in restore the tissue and to fight against microbial invasion, the samples were tested from the biological point of view by evaluating the biodegradability in phosphate-buffered saline (PBS) and simulated body fluid (SBF) and moreover the antimicrobial effect was performed on Gram-positive bacterium Staphylococcus aureus, Gram-negative bacterium Escherichia coli, and fungi Candida albicans. The results reveal that the obtained material has specific characteristics for bone regeneration.

Keywords: bacterial cellulose, biomaterials, hydroxyapatite, scaffolds materials

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6071 Risk Factors and Regional Difference in the Prevalence of Fecal Carriage Third-Generation Cephalosporin-Resistant E. Coli in Taiwan

Authors: Wan-Ling Jiang, Hsin Chi, Jia-Lu Cheng, Ming-Fang Cheng

Abstract:

Background: Investigating the risk factors for the fecal carriage of third-generation cephalosporin-resistant E.coli could contribute to further disease prevention. Previous research on third-generation cephalosporin-resistant prevalence in children in different regions of Taiwan is limited. This project aims to explore the risk factors and regional differences in the prevalence of third-generation cephalosporin-resistant and other antibiotic-resistant E. coli in the northern, southern, and eastern regions of Taiwan. Methods: We collected data from children aged 0 to 18 from community or outpatient clinics from July 2022 to May 2023 in southern, northern, and eastern Taiwan. The questionnaire was designed to survey the characteristics of participants and possible risk factors, such as clinical information, household environment, drinking water, and food habits. After collecting fecal samples and isolating stool culture with E.coli, antibiotic sensitivity tests and MLST typing were performed. Questionnaires were used to analyze the risk factors of third-generation cephalosporin-resistant E. coli in the three different regions of Taiwan. Results: In the total 246 stool samples, third-generation cephalosporin-resistant E.coli accounted for 37.4% (97/246) of all isolates. Among the three different regions of Taiwan, the highest prevalence of fecal carriage with third-generation cephalosporin-resistant E.coli was observed in southern Taiwan (42.7%), followed by northern Taiwan (35.5%) and eastern Taiwan (28.4%). Multi-drug resistant E. coli had prevalence rates of 51.9%, 66.3%, and 37.1% in the northern, southern, and eastern regions, respectively. MLST typing revealed that ST131 was the most prevalent type (11.8%). The prevalence of ST131 in northern, southern, and eastern Taiwan was 10.1%, 12.3%, and 13.2%, respectively. Risk factors analysis identified lower paternal education, overweight status, and non-vegetarian diet as statistical significance risk factors for third-generation cephalosporin-resistant E.coli. Conclusion: The fecal carriage rates of antibiotic-resistant E. coli among Taiwanese children were on the rise. This study found regional disparities in the prevalence of third-generation cephalosporin-resistant and multi-drug-resistant E. coli, with southern Taiwan having the highest prevalence. Lower paternal education, overweight, and non-vegetarian diet were the potential risk factors of third-generation cephalosporin-resistant E. coli in this study.

Keywords: Escherichia coli, fecal carriage, antimicrobial resistance, risk factors, prevalence

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6070 An Ecological Systems Approach to Risk and Protective Factors of Sibling Conflict for Children in the United Kingdom

Authors: C. A. Bradley, D. Patsios, D. Berridge

Abstract:

This paper presents evidence to better understand the risk and protective factors related to sibling conflict and the patterns of association between sibling conflict and negative adjustment outcomes by incorporating additional familial and societal factors within statistical models of risk and adjustment. It was conducted through the secondary analysis of a large representative cross-sectional dataset of children in the UK. The original study includes proxy interviews for young children and self-report interviews for adolescents. The study applies an ecological systems framework for the analyses. Hierarchical regression models assess risk and protective factors and adjustment outcomes associated with sibling conflict. Interactions reveal differential effect between contextual risk factors and the social context of influence. The general pattern of findings suggested that, although factors affecting likelihood of experiencing sibling conflict were often determined by child age, some remained consistent across childhood. These factors were often conditional on each other, reinforcing the importance of an ecological framework. Across both age-groups, sibling conflict was associated with siblings closer in age; male sibling groups; most advantaged socio-economic group; and exposure to community violence, such as witnessing violent assault or robbery. The study develops the evidence base on the influence of ethnicity and socio-economic group on sibling conflict by exploring interactions between social context. It also identifies key new areas of influence – such as family structure, disability, and community violence in exacerbating or reducing risk of conflict. The study found negative associations between sibling conflict and young children’s mental well-being and adolescents' mental well-being and anti-social behaviour, but also more context specific associations – such as sibling conflict moderating the negative impact of adversity and high risk experiences for young children such as parental violence toward the child.

Keywords: adjustment, conflict, ecological systems, family systems, risk and protective factors, sibling

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6069 Flood Hazard and Risk Mapping to Assess Ice-Jam Flood Mitigation Measures

Authors: Karl-Erich Lindenschmidt, Apurba Das, Joel Trudell, Keanne Russell

Abstract:

In this presentation, we explore options for mitigating ice-jam flooding along the Athabasca River in western Canada. Not only flood hazard, expressed in this case as the probability of flood depths and extents being exceeded, but also flood risk, in which annual expected damages are calculated. Flood risk is calculated, which allows a cost-benefit analysis to be made so that decisions on the best mitigation options are not based solely on flood hazard but also on the costs related to flood damages and the benefits of mitigation. The river ice model is used to simulate extreme ice-jam flood events with which scenarios are run to determine flood exposure and damages in flood-prone areas along the river. We will concentrate on three mitigation options – the placement of a dike, artificial breakage of the ice cover along the river, the installation of an ice-control structure, and the construction of a reservoir. However, any mitigation option is not totally failsafe. For example, dikes can still be overtopped and breached, and ice jams may still occur in areas of the river where ice covers have been artificially broken up. Hence, for all options, it is recommended that zoning of building developments away from greater flood hazard areas be upheld. Flood mitigation can have a negative effect of giving inhabitants a false sense of security that flooding may not happen again, leading to zoning policies being relaxed. (Text adapted from Lindenschmidt [2022] "Ice Destabilization Study - Phase 2", submitted to the Regional Municipality of Wood Buffalo, Alberta, Canada)

Keywords: ice jam, flood hazard, flood risk river ice modelling, flood risk

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6068 PrEP and Risk: Challenges for an Emerging Sanitary Pact

Authors: Roberto Rubem Silva-Brandao, Aurea Maria Zollner Ianni

Abstract:

This article discusses the use and the incorporation of Pre-exposure Prophylaxis for HIV (PrEP) within a risk society context. Considering contemporary social theoreticians, we discuss implications of biotechnological uses for health enhancement. Firstly, we explore examples of biological manipulation and its consequences of use on given ecological dynamics, particularly taking into account other Sexually Transmitted Infections. In addition, we discuss how HIV resistance cases occurred with people on PrEP and its possible consequences on population-based interventions. Moreover, we present recent studies that analyze biological modifications on bodies of those who are on consistent use of PrEP, and how these body modifications are addressed on common practices of Public Health. Secondly, we present our theoretical references, which are intended to the analysis that situates our contemporary society in the reflexive stage of modernization. We discuss limits of biological use by individuals and how this can fabric feelings of freedom and autonomy within the individualization process and health. Finally, we argue that biotechnological uses on health, specifically on Public Health, tackling the risk aspects of its application, shows that another sanitary pact is needed.

Keywords: PrEP, public health, social sciences, risk society

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6067 Fuzzy Inference System for Risk Assessment Evaluation of Wheat Flour Product Manufacturing Systems

Authors: Yas Barzegaar, Atrin Barzegar

Abstract:

The aim of this research is to develop an intelligent system to analyze the risk level of wheat flour product manufacturing system. The model consists of five Fuzzy Inference Systems in two different layers to analyse the risk of a wheat flour product manufacturing system. The first layer of the model consists of four Fuzzy Inference Systems with three criteria. The output of each one of the Physical, Chemical, Biological and Environmental Failures will be the input of the final manufacturing systems. The proposed model based on Mamdani Fuzzy Inference Systems gives a performance ranking of wheat flour products manufacturing systems. The first step is obtaining data to identify the failure modes from expert’s opinions. The second step is the fuzzification process to convert crisp input to a fuzzy set., then the IF-then fuzzy rule applied through inference engine, and in the final step, the defuzzification process is applied to convert the fuzzy output into real numbers.

Keywords: failure modes, fuzzy rules, fuzzy inference system, risk assessment

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6066 Numerical and Experimental Investigation of Fracture Mechanism in Paintings on Wood

Authors: Mohammad Jamalabadi, Noemi Zabari, Lukasz Bratasz

Abstract:

Panel paintings -complex multi-layer structures consisting of wood support and a paint layer composed of a preparatory layer of gesso, paints, and varnishes- are among the category of cultural objects most vulnerable to relative humidity fluctuations and frequently found in museum collections. The current environmental specifications in museums have been derived using the criterion of crack initiation in an undamaged, usually new gesso layer laid on wood. In reality, historical paintings exhibit complex crack patterns called craquelures. The present paper analyses the structural response of a paint layer with a virtual network of rectangular cracks under environmental loadings using a three-dimensional model of a panel painting. Two modes of loading are considered -one induced by one-dimensional moisture response of wood support, termed the tangential loading, and the other isotropic induced by drying shrinkage of the gesso layer. The superposition of the two modes is also analysed. The modelling showed that minimum distances between cracks parallel to the wood grain depended on the gesso stiffness under the tangential loading. In spite of a non-zero Poisson’s ratio, gesso cracks perpendicular to the wood grain could not be generated by the moisture response of wood support. The isotropic drying shrinkage of gesso produced cracks that were almost evenly spaced in both directions. The modelling results were cross-checked with crack patterns obtained on a mock-up of a panel painting exposed to a number of extreme environmental variations in an environmental chamber.

Keywords: fracture saturation, surface cracking, paintings on wood, wood panels

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6065 Chemotactic Behaviour of Human Mesenchymal Stem Cells in Response to Silicate Substituted Hydroxyapatite

Authors: Dinara Ikramova, Karin A. Hing, Simon C. F. Rawlinson

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Silicate-substituted hydroxyapatite (SiHA) has been shown to enhance bone regeneration in vivo compared with phase pure stoichiometric hydroxyapatite. Evidence suggests that substrate chemistry dependent formation of a permissive protein layer on the surface of synthetic bone graft substitute materials is key for bioactivity and cell attachment. However, little information is available on whether the substrate chemistry may affect cell migration and recruitment. The aim of this study is to investigate whether or not human Mesenchymal Stem Cells (hMSCs) exhibit a chemotactic response to SiHA porous granules and if it can be linked to either the ion exchange or protein sequestering and enrichment on the surface of the material. 150mg of SiHA granules with 80% total porosity and 20% strut porosity were incubated in 1ml of either Serum Free Media (SFM) or 10% Serum Containing Media (SCM) under static cell culture conditions (37°C, 5% CO2) in absence of cells. Protein sequestering and exchange of calcium, phosphate and silicate ions were analysed at 0.5, 1, 2, 4, 8, 16 and 24 hours with n=12 per time point. Migration of hMSCs in the presence of 150mg of SiHA granules was assessed over 24 hours using a modified transwell migration system in either SFM or SCM (n=6) with 30% serum containing media acting as a positive control. At 24 hours protein sequestering and ionic exchange were analysed, and the number of cells was quantified using a high throughput confocal microscope (IN Cell Analyser 6000). In acellular condition, both calcium and phosphate ion concentrations in media showed a decrease at 24 hours which was greater in SFM than in SCM. This suggests possible formation and precipitation of a bone like apatite on the surface of SiHA. Reduction in this activity observed in SCM indicates that the presence of serum proteins is interfering with the ion exchange at the material and media interface. Adsorbed protein levels showed fluctuation over time followed by sharp decrease at 24 hours, suggesting a possible protein rearrangement on the surface of the material. The ion analysis performed on SFM and SCM after 24-hour incubation with cells in the presence of granules showed a greater reduction in phosphate concentration in both SFM and SCM compared to phosphate levels in acellular condition. Silicate concentration in SCM increased from 1.6mM (absence of cells) to 5.1mM (presence of cells). This indicates that the cells are promoting the uptake of phosphate and release of silicate ions. No significant change was seen in levels of adsorbed proteins in the presence and absence of cells. Further analysis is required to determine whether the species of these proteins change over time. The analysis of cell migration after 24-hour incubation showed more cells migrating towards the granules, 12.7% in SFM and 8.3% in SCM, than in positive control, 4.5% in SFM and 3.6% in SCM respectively. These results suggest that SiHA has a chemotactic activity independent of serum proteins. A property which has not previously been demonstrated for a synthetic bone graft material.

Keywords: cell migration, hMSCs, SiHA, transwell migration system

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6064 Stability Bound of Ruin Probability in a Reduced Two-Dimensional Risk Model

Authors: Zina Benouaret, Djamil Aissani

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In this work, we introduce the qualitative and quantitative concept of the strong stability method in the risk process modeling two lines of business of the same insurance company or an insurance and re-insurance companies that divide between them both claims and premiums with a certain proportion. The approach proposed is based on the identification of the ruin probability associate to the model considered, with a stationary distribution of a Markov random process called a reversed process. Our objective, after clarifying the condition and the perturbation domain of parameters, is to obtain the stability inequality of the ruin probability which is applied to estimate the approximation error of a model with disturbance parameters by the considered model. In the stability bound obtained, all constants are explicitly written.

Keywords: Markov chain, risk models, ruin probabilities, strong stability analysis

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6063 Impact of Aging on Fatigue Performance of Novel Hybrid HMA

Authors: Faizan Asghar, Mohammad Jamal Khattak

Abstract:

Aging, in general, refers to changes in rheological characteristics of asphalt mixture due to changes in chemical composition over the course of construction and service life of the pavement. The main goal of this study was to investigate the impact of oxidation on fatigue characteristics of a novel HMA composite fabricated with a combination of crumb rubber (CRM) and polyvinyl alcohol (PVA) fiber subject to aging of 7 and 14 days. A flexural beam fatigue test was performed to evaluate several characteristics of control, CRM modified, PVA reinforced, and novel rubber-fiber HMA composite. Experimental results revealed that aging had a significant impact on the fatigue performance of novel HMA composite. It was found that a suitable proportion of CRM and PVA radically affected the performance of novel rubber-fiber HMA in resistance to fracture and fatigue cracking when subjected to long-term aging. The developed novel HMA composite containing 2% CRM and 0.2% PVA presented around 29 times higher resistance to fatigue cracking for a period of 7 days of aging. To develop a cumulative plastic deformation level of 250 micros, such a mixture required over 50 times higher cycles than control HMA. Moreover, the crack propagation rate was reduced by over 90%, with over 12 times higher energy required to propagate a unit crack length in such a mixture compared to conventional HMA. Further, digital imaging correlation analyses revealed a more twisted and convoluted fracture path and higher strain distribution in rubber-fiber HMA composite. The fatigue performance after long-term aging of such novel HMA composite explicitly validates the ability to withstand load repetition that could lead to an extension in the service life of pavement infrastructure and reduce taxpayers’ dollars spent.

Keywords: crumb rubber, PVA fibers, dry process, aging, performance testing, fatigue life

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6062 Cardiotoxicity Associated with Radiation Therapy: The Role of Bone Marrow Mesenchymal Cells in Improvement of Heart Function

Authors: Isalira Peroba Ramos, Cherley Borba Vieira de Andrade, Grazielle Suhett, Camila Salata, Paulo Cesar Canary, Guilherme Visconde Brasil, Antonio Carlos Campos de Carvalho, Regina Coeli dos Santos Goldenberg

Abstract:

Background: The therapeutic options for patients with cancer now include increasingly complex combinations of medications, radiation therapy (RT), and surgical intervention. Many of these treatments have important potential adverse cardiac effects and are likely to have significant effects on patient outcomes. Cell therapy appears to be promising for the treatment of chronic and degenerative diseases, including cardiomyopathy induced by RT, as the current therapeutic options are insufficient. Aims: To evaluate the potential of bone marrow mesenchymal cells (BMMCs) in radioinduced cardiac damage Methods: Female Wistar rats, 3 months old (Ethics Committee 054/14), were divided into 2 groups, non-treated irradiated group (IR n=15) and irradiated and BMMC treated (IRT n=10). Echocardiography was performed to evaluate heart function. After euthanasia, 3 months post treatment; the left ventricle was removed and prepared for RT-qPCR (VEGF and Pro Collagen I) and histological (picrosirius) analysis. Results: In both groups, 45 days after irradiation, ejection fraction (EF) was in the normal range for these animals (> 70%). However, the BMMC treated group had EF (83.1%±2.6) while the non-treated IR group showed a significant reduction (76.1%±2.6) in relation to the treated group. In addition, we observed an increase in VEGF gene expression and a decrease in Pro Collagen I in IRT when compared to IR group. We also observed by histology that the collagen deposition was reduced in IRT (10.26%±0.83) when compared to IR group (25.29%±0.96). Conclusions: Treatment with BMMCs was able to prevent ejection fraction reduction and collagen deposition in irradiated animals. The increase of VEGF and the decrease of pro collagen I gene expression might explain, at least in part, the cell therapy benefits. All authors disclose no financial or personal relationships with individuals or organizations that could be perceived to bias their work. Sources of funding: FAPERJ, CAPES, CNPq, MCT.

Keywords: mesenchymal cells, radioation, cardiotoxicity, bone marrow

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