Search results for: chronic fatigue syndrome

Authors: Ayhan Eymirli, Sila N. Usta

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The aim of this study is the comparison of the cyclic fatigue resistance of EndoArt Gold (EAG, Inci Dental, Istanbul, Turkey), EndoArt Blue (EAB, Inci Dental, Istanbul, Turkey), ProTaper Universal (PTU, Dentsply Tulsa Dental Specialties), and ProTaper Gold (PTG, Dentsply Tulsa Dental Specialties) files at body temperature. Twelve instruments of each EAG, EAB, PTU, PTG file system were included in this study. All selected files were rotated in the artificial canals, which have a 60° angle and a 5-mm radius of curvature until fracture occurred. The time to fracture (Ttf) was measured in seconds by a chronometer in the control panel that presents in the cyclic fatigue testing device when a fracture was detected visually and/or audibly. The lengths of the fractured fragments (FL) were also measured with a digital microcaliper. The data of Ttf and FL were analyzed using Kruskal-Wallis, one-way ANOVA and post hoc Bonferroni tests at the 5% significance level. There was a statistically significant difference among the file systems (p < 0.05). EAB had the statistically highest fatigue resistance, and PTU had the statistically lowest fatigue resistance (p < 0.05). PTG system had a statistically higher FL means than EAB and PTU file systems (p < 0.05). EAB had the greatest cyclic fatigue resistance amongst the other file systems. It can be stated that heat treatments may be a factor that increases fatigue resistance.

Keywords: cyclic fatigue resistance, Endo art blue, Endo art gold, pro taper gold, pro taper universal

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Authors: Djamel Djeghader, Bachir Redjel

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The composite materials of glass fibers can be used as a repair material for damage elements under repeated stresses, and in various environments. A cyclic bending characterization of a glass/polyester composite material was carried out with consideration of the period of immersion in water. These tests describe the behavior of materials and identify the mechanical fatigue characteristics using the Wohler Curve for different immersion time: 0, 90, 180 and 270 days in water. These curves are characterized by a dispersion in the lifetimes were modeled by straight whose intercepts are very similar and comparable to the static strength. This material deteriorates fatigue at a constant rate, which increases with increasing immersion time in water at a constant speed. The endurance limit seems to be independent of the immersion time in the water.

Keywords: fatigue, composite, glass, polyester, immersion, wohler

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Authors: Bremmy Laksono, Nurul Qomarilla, Riksa Parikrama, Dyan K. Nugrahaeni, Willyanti Soewondo, Dadang S. H. Effendi, Eriska Rianti, Arlette S. Setiawan, Ine Sasmita, Risti S. Primanti, Erna Kurnikasari, Yunia Sribudiani

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Down syndrome is a chromosomal abnormality of chromosome 21 which can appear in man or woman. Maternal age and paternal age, history of radiation are the common risk factors. This study was conducted to observe risk factors which related as causes of Down syndrome. In this case control study using purposive sampling technique, 84 respondents were chosen from Cell Culture and Cytogenetics Laboratory patients in Faculty of Medicine, Universitas Padjadjaran, Indonesia. They were used as study samples and divided into 42 Down syndrome cases and 42 control respondents. This study used univariate and bivariate analysis (chi-square). Samples population were West Java residents, the biggest province in Indonesia in number of population. The results showed maternal age, paternal age, history of radiation exposure and family history were not significantly related to Down syndrome baby. Moreover, all of those factors also did not contribute to the risk of having a child with Down syndrome in patients at Cell Culture and Cytogenetics Laboratory, Faculty of Medicine, Universitas Padjadjaran. Therefore, we should investigate other risk factors of Down syndrome in West Java population.

Keywords: down syndrome, family history, maternal age, paternal age, risk factor

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Authors: S. M. C. Kelly, M. Goulden

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Introduction: Chronic Pancreatitis is an increasing problem worldwide. Pain is the main symptom and the main reason for hospital readmission following diagnosis, despite the use of strong analgesics including opioids. Ketamine infusions reduce pain in complex regional pain syndrome and other neuropathic pain conditions. Our centre has trialed the use of ketamine infusions in patients with chronic pancreatitis. We have evaluated this service to assess whether ketamine reduces emergency department admissions and analgesia requirements. Methods: This study collected retrospective data from 2010 in all patients who received a ketamine infusion for chronic pain secondary to a diagnosis of chronic pancreatitis. The day-case ketamine infusions were initiated in theatre by an anaesthetist, with standard monitoring and the assistance of an anaesthetic practitioner. A bolus dose of 0.5milligrams/kilogram was given in theatre. The infusion of 0.5 milligrams/kilogram per hour was then administered over a 6 hour period in the theatre recovery area. A study proforma detailed the medical history, analgesic use and admissions to hospital. Patients received a telephone follow up consultation. Results: Over the last eight years, a total of 30 patients have received intravenous ketamine infusions, with a total of 92 ketamine infusions being administered. 53% of the patients were male with the average age of 47. A total of 27 patients participated with the telephone consultation. A third of patients reported a reduction in hospital admissions with pain following the ketamine infusion. Analgesia requirements were reduced by an average of 48.3% (range 0-100%) for an average duration of 69.6 days (range 0-180 days.) Discussion: This service evaluation illustrates that ketamine infusions can reduce analgesic requirements and the number of hospital admissions in patients with chronic pancreatitis. In the light of increasing pressures on Emergency departments and the increasing evidence of the dangers of long-term opioid use, this is clearly a useful finding. We are now performing a prospective study to assess the long-term effectiveness of ketamine infusions in reducing analgesia requirements and improving patient’s quality of life.

Keywords: acute-on-chronic pain, intravenous analgesia infusion, ketamine, pancreatitis

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Authors: Chia-Pei Chen, Yu-Ju Chen, Yu-Juei Hsu

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The prevalence and incidence of end-stage renal disease in Taiwan ranks the highest in the world. According to the statistical survey of the Ministry of Health and Welfare in 2019, kidney disease is the ninth leading cause of death in Taiwan. It leads to autonomic dysfunction, inflammatory response and symptom distress, and further increases the damage to the structure and function of the kidneys, leading to increased demand for renal replacement therapy and risks of cardiovascular disease, which also has medical costs for the society. If we can intervene in a feasible manual to effectively regulate the autonomic nerve function of CKD patients, reduce the inflammatory response and symptom distress. To prolong the progression of the disease, it will be the main goal of caring for CKD patients. This study aims to test the effect of heart rate variability biofeedback (HRVBF) on improving autonomic nerve function (Heart Rate Variability, HRV), inflammatory response (Interleukin-6 [IL-6], C reaction protein [CRP] ), symptom distress (Piper fatigue scale, Pittsburgh Sleep Quality Index [PSQI], and Beck Depression Inventory-II [BDI-II] ) in patients with chronic kidney disease. This study was experimental research, with a convenience sampling. Participants were recruited from the nephrology clinic at a medical center in northern Taiwan. With signed informed consent, participants were randomly assigned to the HRVBF or control group by using the Excel BINOMDIST function. The HRVBF group received four weekly hospital-based HRVBF training, and 8 weeks of home-based self-practice was done with StressEraser. The control group received usual care. We followed all participants for 3 months, in which we repeatedly measured their autonomic nerve function (HRV), inflammatory response (IL-6, CRP), and symptom distress (Piper fatigue scale, PSQI, and BDI-II) on their first day of study participation (baselines), 1 month, and 3 months after the intervention to test the effects of HRVBF. The results were analyzed by SPSS version 23.0 statistical software. The data of demographics, HRV, IL-6, CRP, Piper fatigue scale, PSQI, and BDI-II were analyzed by descriptive statistics. To test for differences between and within groups in all outcome variables, it was used by paired sample t-test, independent sample t-test, Wilcoxon Signed-Rank test and Mann-Whitney U test. Results: Thirty-four patients with chronic kidney disease were enrolled, but three of them were lost to follow-up. The remaining 31 patients completed the study, including 15 in the HRVBF group and 16 in the control group. The characteristics of the two groups were not significantly different. The four-week hospital-based HRVBF training combined with eight-week home-based self-practice can effectively enhance the parasympathetic nerve performance for patients with chronic kidney disease, which may against the disease-related parasympathetic nerve inhibition. In the inflammatory response, IL-6 and CRP in the HRVBF group could not achieve significant improvement when compared with the control group. Self-reported fatigue and depression significantly decreased in the HRVBF group, but they still failed to achieve a significant difference between the two groups. HRVBF has no significant effect on improving the sleep quality for CKD patients.

Keywords: heart rate variability biofeedback, autonomic nerve function, inflammatory response, symptom distress, chronic kidney disease

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Authors: Parul Garg

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Bouveret Syndrome is a rare presentation described as Gastric Outlet Obstruction secondary to Gallstone Ileus. Here we describe the 3-year progression of disease from cholelithiasis to gallstone ileus with relevant imaging findings. The patient was treated under an Upper Gastrointestinal Surgery service with surgical intervention in the form of a laparoscopic assisted procedure with midline laparotomy. She recovered well and was discharged 1 week post operatively. No complications occurred.

Keywords: Cholelithiasis, Bouveret syndrome, Gallstone Ileus, gastric outlet obstruction

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Authors: Birendra Kumar Jha, Mingma L. Sherpa, Binod Kumar Dahal

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Background: The metabolic syndrome is emerging as a major public health concern in the world. Urbanization, surplus energy uptake, compounded by decreased physical activities, and increasing obesity are the major factors contributing to the epidemic of metabolic syndrome worldwide. However, prevalence of metabolic syndrome and its risk factors are little studied in Terai region of Nepal. The objectives of this research were to estimate the prevalence and to identify the risk factors of metabolic syndrome among adults in Terai region of Nepal. Method: We used a community based cross sectional study design. A total of 225 adults (age: 18 to 80 years) were selected from three district of Terai region of Nepal using cluster sampling by camp approach. IDF criteria (central obesity with any two of following four factors: triglycerides ≥ 150 mg/dl or specific treatment for lipid abnormality, reduced HDL, raised blood pressure and raised fasting plasma glucose or previously diagnosed type 2 diabetes) were used to assess metabolic syndrome. Interview, physical and clinical examination, measurement of fasting blood glucose and lipid profile were conducted for all participants. Chi-square test and multivariable logistic regression were employed to explore the risk factors of metabolic syndrome. Result: The overall prevalence of metabolic syndrome was 70.7%. Hypertension, increased fasting blood sugar, increased triglycerides and decreased HDL were observed in 50.7%, 32.4%, 41.8% and 79.1% of the subjects respectively. Socio-economic and behavioral risk factors significantly associated with metabolic syndrome were gender male (OR=2.56, 955 CI: 1.42-4.63; p=0.002), in service or retired from service (OR=3.72, 95% CI: 1.72-8.03; p=0.001) and smoking (OR= 4.10, 95% CI: 1.19-14.07; p=0.016). Conclusion: Higher prevalence of Metabolic syndrome along with presence of behavioral risk factors in Terai region of Nepal likely suggest lack of awareness and health promotion activities for metabolic syndrome and indicate the need to promote public health programs in this region to maintain quality of life.

Keywords: metabolic syndrome, Nepal, prevalence, risk factors, Terai

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Authors: Harish Ramesh Babu, Marco Böcker, Mario Raddatz, Sebastian Henkel, Horst Biermann, Uwe Gampe

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Thermal power machines are subjected to cyclic loading conditions under elevated temperatures. At these extreme conditions, the durability of the components has a significant influence. The material mechanical behaviour has to be known in detail for a failsafe construction. For this study a nickel-based alloy is considered, the deformation and fatigue behaviour of the material is analysed under cyclic loading. A viscoplastic model is used for calculating the deformation behaviour as well as to simulate the rate-dependent and cyclic plasticity effects. Finally, the cyclic deformation results of the finite element simulations are compared with low cycle fatigue (LCF) experiments.

Keywords: complex low cycle fatigue, elevated temperature, fe-simulation, viscoplastic

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Authors: Mohit Chauhan, Atul Narayan

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Moisture damage is the continuous deterioration of asphalt concrete mixtures by the loss of adhesive bond between the asphalt binder and aggregates, or loss of cohesive bonds within the asphalt binder in the presence of moisture. Moisture has been known to either cause or exacerbates distresses in asphalt concrete pavements. Since moisture would often retain for a relatively long duration at the bottom of asphalt concrete layer, the movement of traffic loading in this saturated condition would cause excess stresses or strains within the mixture. This would accelerate the degradation of the adhesion and cohesion within the mixture and likely to contribute the development of fatigue cracking in asphalt concrete pavements. In view of this, it is important to investigate the effect of moisture on the fatigue behavior of asphalt concrete mixtures. In this study, changes in fatigue characteristics after moisture conditioning were evaluated by conducting four-point beam fatigue tests on dry and moisture conditioned specimens. For this purpose, mixtures with two different types of binders were prepared and saturated with moisture using 700 mm Hg vacuum. Beam specimens, in this way, were taken to a saturation level of 65-75 percent. After preconditioning specimens in this degree of saturation and 60°C for a period of 24 hours, they were subjected to four point beam fatigue tests in strain-controlled mode with a strain amplitude of 400 microstrain. The results were then compared with the fatigue test results obtained with beam specimens that were not subjected to moisture conditioning. Test results show that the conditioning reduces both fatigue life and initial flexural stiffness of specimen significantly. The moisture conditioning was also found to increase the rate of reduction of flexural stiffness. Moreover, it was observed that the fatigue life ratio (FLR), the ratio of the fatigue life of the moisture conditioned sample to that of the dry sample, is significantly lower than the flexural stiffness ratio (FSR). The study indicates that four-point bending test is an appropriate tool with FLR and FSR as the potential parameters for moisture-sensitivity evaluation.

Keywords: asphalt concrete, fatigue cracking, moisture damage, preconditioning

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Authors: Hiroshi Ikeda

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In this research, a questionnaire survey was conducted to measure nap, drowsiness and fatigue of drivers who work long shifts, to discuss about the work environment and health conditions for taxi and bus drivers who work at night time. The questionnaire sheet used for this research was organized into the following categories: tension/tiredness, drowsiness while driving, and the nap situation during night-time work. The number of taxi drivers was 127 and the number of bus drivers was 40. Concerning the results of a comparison of nap hours of taxi and bus drivers, the taxi drivers’ nap hours are overwhelmingly shorter, and also the frequency of drivers who feel drowsiness is higher. The burden on bus drivers does not change because of the system of a two-driver rotation shift. In particular, the working environment of the taxi driver may lead to greater fatigue accumulation than the bus driver’s environment.

Keywords: bus and taxi, drowsiness, fatigue, nap

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Authors: Mozhgan Aliakbari, Sara Moridpour

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In recent years, much attention has been given to truck drivers’ fatigue management. Long working hours negatively influence truck drivers’ physiology, health, and safety. However, there is little empirical research in the heavy vehicle transport sector in Australia to identify the influence of working hours’ management on drivers’ fatigue and consequently, on the risk of crashes and injuries. There is no national legislation regulating the number of hours or kilometres travelled by truck drivers. Consequently, it is almost impossible to define a standard number of hours or kilometres for truck drivers in a safety management system. This paper reviews the existing studies concerning safe system interventions such as tachographs in relation to fatigue caused by long working hours. This paper also reviews the literature to identify the influence of frequency of rest breaks on the reduction of work-related road transport accidents involving trucks. A framework is presented to manage truck drivers’ fatigue, which may result in the reduction of injuries and fatalities involving heavy vehicles.

Keywords: fatigue, time management, trucks, traffic safety

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Authors: Sana Ilyas

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Parry-Romberg syndrome is a rare condition clinically defined by slowly progressive atrophy of the skin and soft tissues. This usually effects one side of the face, although a few cases have been documented of bilateral presentation. It is more prevalent in females and usually affects the left side of the face. The syndrome can also be accompanied by neurological abnormalities. It usually occurs in the first two decades of life with a variable rate of progression. The aetiology is unknown, and the disease eventually stabilises. The treatment options usually involve surgical management. The least invasive of these options is the management of facial asymmetry, associated with Parry Romberg syndrome, through the use of tissue fillers. This paper will review the existing literature on the management of Parry Romberg syndrome with tissue filler. Aim: The aim of the study is to explore the current published literature for the management of Parry Romberg syndrome with fillers. It is to assess the development that has been made in this method of management, its benefits and limitations, and its effectiveness for the management of Parry Romberg syndrome. Methodology: There was a thorough assessment of the current literature published on this topic. PubMed database was used for search of the published literature on this method of the management. Papers were analysed and compared with one another to assess the success and limitation of the management of Parry Romberg with dermal fillers Results and Conclusion: Case reports of the use of tissue fillers discuss the varying degrees of success with the treatment. However, this procedure has it’s limitation, which are discussed in the paper in detail. However, it is still the least invasive of all the surgical options for the management of Parry Romberg Syndrome, and therefore, it is important to explore this option with patients, as they may be more comfortable with pursuingtreatment that is less invasive and can still improve their facial asymmetry

Keywords: dermal fillers, facial asymmetry, parry romberg syndrome, tissue fillers

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Authors: Nikfarid Lida, Maryam Rassouli, Leili Borimnejad, Hamid Alavi Majd

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Purpose: Chronic sorrow is experienced by mothers of children with cancer. It is a multidimensional concept and is experienced by mothers in different ways depends on their various contexts. Little is known about the concept of chronic sorrow in mothers of children with cancer living in Iran. This study aimed to clarify the concept and explain lived experiences of chronic sorrow in Iranian mothers of children with cancer. Methods: In this hermeneutic phenomenological study, 8 mothers of children with cancer participated in semi structured in-depth interviews about their experiences of chronic sorrow. Interviews continued until data saturation was reached. All interviews were recorded, transcribed, analyzed, and interpreted using 7 steps of the Dickelman et al’s phenomenological approach. Results: Three main themes emerged from mothers’ experiences of chronic sorrow related to child’s cancer. These main themes were ‘climbing up shaky rocks,’ ‘fear and hope,’ and ‘continuous role changing.’ Each of these themes consisted of several subthemes. Conclusion: There are similarities in experiencing chronic sorrow by mothers of children with chronic diseases in different societies. However some experiences are unique in Iranian mothers of children with cancer.

Keywords: cancer, children, mothers, Iran, phenomenology

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Authors: James M. Geidner

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Objective: The purpose of this meta-analysis was to examine the evidence for the effectiveness of exercise interventions on reducing metabolic components in children and/or adolescents diagnosed with Paediatric Metabolic Syndrome. Methods: A computerized search was made from four databases: PubMed, PsycInfo, SPORTDiscus, Cochrane Central Register. The analysis was restricted to children and adolescents with metabolic syndrome examining the effect of exercise interventions on metabolic components. Effect size and 95% confidence interval were calculated and the heterogeneity of the studies was estimated using Cochran’s Q-statistic and I2. Bias was assessed using multiple tools and statistical analyses. Results: Thirteen studies, consisting of 19 separate trials, were selected for the meta-analysis as they fulfilled the inclusion criteria (n=908). Exercise interventions resulted in decreased waist circumference, systolic blood pressure, diastolic blood pressure, fasting glucose, insulin resistance, triglycerides, and High-Density Lipoprotein Cholesterol (HDL-C). Conclusions: This meta-analysis provides insights into the effectiveness of exercise interventions on markers of Paediatric Metabolic Syndrome in children and adolescents.

Keywords: metabolic syndrome, syndrome x, pediatric, meta-analysis

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Authors: Yu-Wen Lin, Li-Ni Liu

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Introduction: Fatigue is the most common symptoms experienced by cancer patients undergoing chemotherapy. Patients receiving anticancer therapies develop a higher proportion of fatigue compared with patients who do not receive anticancer therapies. Fatigue has significant impacts on quality of life, daily activities, mood status, and social behaviors. A warm-water footbath (WWF) at 41℃ promotes circulation and removes metabolites resulting in improving sleep and relieving fatigue. The aim of this study is to determine the effectiveness of WWF for relieving fatigue with cancer patients undergoing chemotherapy. Materials and Methods: This is a single-center, prospective, quasi-experimental design study in the oncology ward in Taiwan. Participants in this study were assigned to WWF group as experimental group and standard care group as a control group by purposive sampling. In the WWF group, the participants were asked to soak their feet in 42-43℃ water 15 minutes for consecutive 6 days at one day before chemotherapy. Each participant was evaluated for fatigue level by the Taiwanese version of the Brief Fatigue Inventory (BFI-T). BFI-T was completed for consecutive 8 days of the study. The primary outcome was compared the BFI-T score of WWF group to the standard care group. Results: There were 60 participants enrolled in this study. Thirty participants were assigned to WWF group and 30 participants were assigned to standard care group. Both groups have comparable characteristic. The BFI-T scores of both groups were increased associated with the days of chemotherapy. The highest BFI-T scores of both groups were on the day 4 of chemotherapy. The BFI-T scores of both groups were decreased since day 5 and significantly decreased in WWF group on day 5 compared to standard care group (4.17 vs. 5.7, P ＜ .05). At the end of the study the fatigue at its worse were significantly decreased in WWF group (2.33 vs. 4.37, P ＜ .001). There was no adverse event reported in this study. Conclusion: WWF is an easy, safe, non-invasive, and relatively inexpensive nursing intervention for improving fatigue of cancer patients undergoing chemotherapy. In summary, this study shows the WWF is a simple complementary care method, and it is effective for improving and relieving fatigue in a short time. Through improving fatigue is a way to enhance the quality of life which is important for cancer patients undergoing chemotherapy. Larger prospective randomized controlled trial and long-term effectiveness and outcomes of WWF should be performed to confirm this study.

Keywords: chemotherapy, warm-water footbath, fatigue, Taiwanese version of the brief fatigue inventory

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Authors: Abdul-Monim Batiha

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Aim: The aim of this study were to correlate Jordanian cancer patients’ quality of life and fatigue with selected variables (age, sex, religion, marital status, level of education, type of cancer, number of people living in the same household, type of radiotherapy, dose of radiotherapy, and hemoglobin level). Background: Radiotherapy and chemotherapy remain devastating agents that altered patients’ normal lives. Methods: A correlational design was used in this study to 80 cancer patients and required radiotherapy treatment using a convenience sampling procedure. Results: No significant differences were found in the relationship between quality of life scores and selected variables. A significant negative relationship was found between quality of life scores and the side effects of radiotherapy treatment. Significant positive relationships were found between fatigue scores measured by Piper Fatigue Scale and cancer complications, and radiotherapy side effects. Conclusion: Cancer patients’ quality of life and fatigue are affected by radiotherapy’s side effects and cancer complications. Implications for Nursing: Nurses should try to prevent and manage the negative side effects of radiotherapy and complications of cancer. Such an initiative would serve to design specific nursing interventions that have the potential to help patients enjoy their lives and perform their activities.

Keywords: cancer patients, piper fatigue scale, fatigue, quality of life, radiotherapy

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Authors: John Gaber, Youssef Ahmed, Hossam A.Gabbar, Jing Ren

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Nuclear Power Plant (NPP) operators have a large responsibility on their shoulders. They must allow the plant to generate a high amount of energy while inspecting and maintaining the safety of the plant. This type of occupation comes with high amounts of mental fatigue, and a small mistake can have grave consequences. Electroencephalography (EEG) is a method of gathering the electromagnetic waves emitted by a human brain. We propose a safety system by monitoring brainwaves for signs of mental fatigue. This requires an analysis of the tasks and mental models of the NPP operator, as well as risk factors on mental fatigue and attention that NPP operators face when performing their tasks. The brain waves generated from experiencing mental fatigue can then be monitored for. These factors are analyzed, developing an EEG-based monitoring system, which aims to alert NPP operators when levels of mental fatigue and attention start affecting their performance in task completion.

Keywords: EEG, power plant operator, psychology, task analysis

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Authors: Piyas Palit, Urbi Pal, Jitendra Mathur, Santanu Das

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Bearing is an important machinery part in the industry. When bearings fail to meet their expected life the consequences are increased downtime, loss of revenue and missed the delivery. This article describes the failure of a gearbox bearing in rolling contact fatigue. The investigation consists of visual observation, chemical analysis, characterization of microstructures using optical microscopes and hardness test. The present study also considers bearing life as well as the operational condition of bearings. Surface-initiated rolling contact fatigue, leading to a surface failure known as pitting, is a life-limiting failure mode in many modern machine elements, particularly rolling element bearings. Metallography analysis of crack propagation, crack morphology was also described. Indication of fatigue spalling in the ferrography test was also discussed. The analysis suggested the probable reasons for such kind of failure in operation. This type of spalling occurred due to (1) heavier external loading condition or (2) exceeds its service life.

Keywords: bearing, rolling contact fatigue, bearing life

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Authors: H. Pasternak, A. Chwastek

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The paper describes the results from a research project about repair of welds. The repair was carried out by grinding the flawed seams and re-welding them. The main task was to determine the FAT classes of original state and after repair of seams according to the assessment procedures, such as nominal, structural and effective notch stress approach. The first part shows the results of the tests, the second part encloses numerical analysis and evaluation of results to determine the fatigue strength classes according to three assessment procedures.

Keywords: cyclic loading, fatigue crack, post-weld treatment, seams’ repair

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Authors: Sung-Uk Wee, Chang-Sung Seok, Jae-Mean Koo, Jeong-Min Lee

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Gas turbine blade is important part of power plant, so it is necessary to evaluate gas turbine reliability. For better heat efficiency, inlet temperature of gas turbine has been elevated more and more so gas turbine blade is exposed to high-temperature environment. Then, higher inlet temperature affects mechanical behavior of the gas turbine blade, so it is necessary that evaluation of mechanical property of gas turbine blade at high-temperature environment. In this study, tensile test and fatigue test were performed at various high temperature, and fatigue life was predicted by Coffin-Manson equation at each temperature. The experimental results showed that gas turbine blade has a lower elastic modulus and shorter fatigue life at higher temperature.

Keywords: gas turbine blade, tensile test, fatigue life, stress-strain

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Authors: Deepika Sudevan, Patrick Rozycki, Laurent Gornet

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This paper presents the experimental identification of the fatigue limit for pristine and impacted Carbon Fiber Reinforced Epoxy polymer (CFRP) woven composites based on the relatively new self-heating methodology for composites. CFRP composites of [0/90]8 and quasi isotropic configurations prepared using hand-layup technique are subjected to low energy impacts (20 J energy) simulating a barely visible impact damage (BVID). Runway debris strike, tool drop or hailstone impact can cause a BVID on an aircraft fuselage made of carbon composites and hence understanding the post-impact fatigue response of CFRP laminates is of immense importance to the aerospace community. The BVID zone on the specimens is characterized using X-ray Tomography technique. Both pristine and impacted specimens are subjected to several blocks of constant amplitude (CA) fatigue loading keeping R-ratio a constant but with increments in the mean loading stress after each block. The number of loading cycles in each block is a subjective parameter and it varies for pristine and impacted CFRP specimens. To monitor the temperature evolution during fatigue loading, thermocouples are pasted on the CFRP specimens at specific locations. The fatigue limit is determined by two strategies, first is by considering the stabilized temperature in every block and second is by considering the change in the temperature slope per block. The results show that both strategies can be adopted to determine the fatigue limit in both pristine and impacted CFRP composites.

Keywords: CFRP, fatigue limit, low energy impact, self-heating, WRM

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Authors: Mehwish Azam, Muhammad Imran, Humaira Jabeen, Sumreen Begum, Rashida Qasim

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Background: Metabolic syndrome is a cluster of metabolic risk factors including obesity, glucose intolerance, insulin resistance, dyslipidemia and hypertension. Metabolic syndrome in obese and type 2 diabetic subjects increases the risk of cardiovascular diseases (CVD). Globally, the prevalence of metabolic syndrome ranges from 10%-50% and in Pakistan ranges from 18%-46%. The objective of the present study is to estimate the prevalence of metabolic syndrome (MS) in obese type 2 diabetic subjects by using International Diabetes Federation (IDF) and National Cholesterol Education Program-Adult Treatment Panel III (NCEP-ATP III) definitions. Methods: Obese type 2 diabetic subjects and normal healthy subjects of both genders were selected from diabetic clinics and hospitals of various localities of Karachi, Pakistan. The frequency of metabolic syndrome was estimated by the proposed definitions of IDF and NCEP-ATP III. Results: The prevalence of metabolic syndrome using International Diabetes Federation (IDF) definition in obese type 2 diabetic subjects was 85.7%. It is significantly higher (p<0.05) in females (47.1%) as compared to males (38.6%). While, using National Cholesterol Education Program-Adult Treatment Panel III (NCEP-ATP III) definition the overall prevalence of metabolic syndrome in obese type 2 diabetic subjects was 75.7%, the prevalence is significantly higher (p<0.05) in females (45.7%) than males (30.0%). Conclusion: It is concluded that, the overall prevalence of metabolic syndrome is increasing significantly in obese type 2 diabetic subjects by using IDF and NCEP–ATP III definitions. Therefore, it is need to initiate the preventive measures by arranging public awareness programmes to highlight the significance of a healthy lifestyle and emphasis should be given to reduce weight, increase physical activity, and increase intake of healthy low-glycemic-index foods.

Keywords: metabolic syndrome, diabetes mellitus, obesity, IDF, NCEP-ATP III

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Authors: Yu-Ching Huang

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Background: Delivery bridges the antepartum and postpartum period. Subsequent fatigue can affect indices, including postpartum recovery and life quality. Milk secretion, breastfeeding quality, and newborn participation may be compromised. Correspondingly, using proper pushing skills during the second stage of labor has the potential to effectively reduce postpartum fatigue and enhance birth satisfaction in new mothers. Purpose: To compare the effects of using different pushing skills on maternal pushing perception, postpartum fatigue, and birth satisfaction. Methodology: The present study used a descriptive research approach and recruited 382 participants from a medical center in northern Taiwan. Data were collected using a structured questionnaire, which included a demographic and obstetrics information datasheet, the Labor Pushing Experience Scale, a fatigue scale, and a birth satisfaction scale. Research Results: Using pushing skills (including upright position [t= 2.28, p < .05] and delayed pushing [t= -1.98, p < .05] during the second stage of labor was shown to enhance birth satisfaction in participants. Additionally, open glottis pushing ( t = 5.46, p < .001) resulted in a mean duration of second-stage labor that was 17.67 minutes less than that achieved using Valsalva pushing. Moreover, a better perceived pushing experience was associated with lower perceived postpartum fatigue (r = .46, p < .05) and higher birth satisfaction (r = -.16, p < .05). Finally, postpartum fatigue perception was negatively associated with birth satisfaction (r = -.16, p < .05). Conclusion and Clinical Application: The findings suggest that midwives should advocate that women adopt upright positions, delayed pushing, and open glottis pushing during the second stage of labor in order to enhance their birth satisfaction.

Keywords: second stage labor duration of pushing skill, pushing experience perception, postpartum fatigue, birth satisfaction

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Authors: Nancy Wilson

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In utero, fetal drug exposure is prevalent amongst birthing facilities. Assessment tools for neonatal abstinence syndrome (NAS) are often cumbersome and ill-fitting, harboring immense subjectivity. This paradox often leads the clinical assessor to be hypervigilant when assessing the newborn for subtle symptoms of NAS, often mistaken for normal newborn behaviors. As a quality improvement initiative, this project led to a more adaptable NAS tool termed eat, sleep, console (ESC). This function-based NAS assessment scores the infant based on the ability to accomplish three basic newborn necessities- to sleep, to eat, and to be consoled. Literature supports that ESC methodology improves patient and family outcomes while providing more cost-effective care.

Keywords: neonatal abstinence syndrome, neonatal opioid withdrawal, maternal substance abuse, pregnancy, and addiction, Finnegan neonatal abstinence syndrome tool, eat, sleep, console

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Authors: Meryem Abi-Ayad, Biagio Arcidiacono, Eusebio Chiefari, Daniela Foti, Mohamed Benyoucef, Antonio Brunetti

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Lipoprotein Lipase (LPL) is a key enzyme for lipid metabolism; its genetic polymorphism can be a candidate for modulating lipids parameters in metabolic syndrome. The objective of the present study was to determine whether lipoproteins lipase polymorphisMetS (LPL-HindIII) could be associated with moderate hypertriglyceridemia (secondary to metabolism syndrome). The polymorphism Hind III (rs320) was assessed by PCR-RFLP in 51 MetS patients and 17 healthy controls from the hospital in Tlemcen. The logistic regression analyses showed no significant association with Hind III genotype and hypertriglyceridemia (TG ≥ 1,5g/l or TG lower treatment) (P=0,455), metabolic syndrome (P=0,455), hypertension (P=0,802) and type 2 diabetes (P=0,144). In terms of plasma biomarkers, although not statistically significant, there was a difference in TG levels (P > 0,05), which was lowest among carriers of the homogenous mutant allele (H-). In this study, there was no association between the rare allele (H-) and disease protection, and between the frequent allele (H+) and disease prevalence (hypertriglyceridemia, metabolic syndrome, hypertension, type 2 diabetes).

Keywords: moderate secondary hypertriglyceridemia, metabolic syndrome, lipids, polymorphism lipoprotein lipase, HindIII(rs320)

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Authors: Morgan Dombroski, Alexis Hartman

Abstract:

Purpose: The present study aimed to explore factors related to overtraining within a female collegiate sample by analyzing the aftereffects of overtraining on athletes' physical and emotional well-being. Methods: 51 female collegiate athletes participated in a de-identified survey to assess factors related to overtraining. All survey questions were derived from the Recovery-Stress Questionnaire. Descriptive and bivariate correlations were conducted to test for significant factors related to the athletes' physical and emotional well-being relating to sports engagement. Results: Descriptive statistics indicated: 80.4% of athletes reported feeling tired from sport-related work, 72.5% reported parts of their body were aching, 47.1% reported feeling emotionally drained, and 37.3% reported feeling burnt out by sport. These findings were consistent with bivariate correlations, which yielded statistically significant findings between physical fatigue and emotional distress. Discussion: In a general sense, athletes increase their training to maximize their performance. The current study aimed to analyze how this training process can result in overtraining of female collegiate athletes, which in turn may negatively impact their physical and emotional functioning. Overtraining syndrome can occur as a maladaptive response to excessive exercise and inappropriate rest caused by systemic inflammation, which negatively affects the central nervous system. The physical manifestations of overtraining can then lead to depressed mood, fatigue, and neurohormonal changes in athletes. To remain competitive and high performing in sports, athletes partaking in excessive training can result in overtraining syndrome, athlete burnout, and compulsive exercise. Additionally, overtrained athletes were defined by displaying high levels of perfectionism, maladaptive coping, and training distress. The current study supported these findings, which yielded a strong correlation between physical and emotional functioning in the context of overtraining in sports. All in all, the environment revolving around sports and the intensity of training can be extremely stressful for athletes. There is a need to monitor athletes’ subjective responses to training, which will allow for early identification of at-risk athletes giving clinicians various opportunities to reduce the negative consequences of overtraining. By better understanding symptoms of emotional and physical fatigue, collegiate sports can become more aware of overtraining symptoms to prevent further detriment to female athletes' overall well-being.

Keywords: burnout, emotionally drained, overtraining, performance, well-being

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Authors: Chanhoe Kang, Changhyun Lee, Seock-Hee Jun, Yeong-Tae Oh

Abstract:

Offshore floating structure under the various environmental conditions maintains a fixed position by mooring system. Environmental conditions, vessel motions and mooring loads are applied to mooring lines as the dynamic tension. Because global responses of mooring system in deep water are specified as wave frequency and low frequency response, they should be calculated from the time-domain analysis due to non-linear dynamic characteristics. To take into account all mooring loads, environmental conditions, added mass and damping terms at each time step, a lot of computation time and capacities are required. Thus, under the premise that reliable fatigue damage could be derived through reasonable analysis method, it is necessary to reduce the analysis cases through the sensitivity studies and appropriate assumptions. In this paper, effects in fatigue are studied for spread mooring system connected with oil FPSO which is positioned in deep water of West Africa offshore. The target FPSO with two Mbbls storage has 16 spread mooring lines (4 bundles x 4 lines). The various sensitivity studies are performed for environmental loads, type of responses, vessel offsets, mooring position, loading conditions and riser behavior. Each parameter applied to the sensitivity studies is investigated from the effects of fatigue damage through fatigue analysis. Based on the sensitivity studies, the following results are presented: Wave loads are more dominant in terms of fatigue than other environment conditions. Wave frequency response causes the higher fatigue damage than low frequency response. The larger vessel offset increases the mean tension and so it results in the increased fatigue damage. The external line of each bundle shows the highest fatigue damage by the governed vessel pitch motion due to swell wave conditions. Among three kinds of loading conditions, ballast condition has the highest fatigue damage due to higher tension. The riser damping occurred by riser behavior tends to reduce the fatigue damage. The various analysis results obtained from these sensitivity studies can be used for a simplified fatigue analysis of spread mooring line as the reference.

Keywords: mooring system, fatigue analysis, time domain, non-linear dynamic characteristics

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Authors: Jan-Tore H. Horn, Jørgen Juncher Jensen

Abstract:

Uncertainties related to fatigue damage estimation of non-linear systems are highly dependent on the tail behaviour and extreme values of the stress range distribution. By using a combination of the First Order Reliability Method (FORM) and Monte Carlo simulations (MCS), the accuracy of the fatigue estimations may be improved for the same computational efforts. The method is applied to a bottom-fixed, monopile-supported large offshore wind turbine, which is a non-linear and dynamically sensitive system. Different curve fitting techniques to the fatigue damage distribution have been used depending on the sea-state dependent response characteristics, and the effect of a bi-linear S-N curve is discussed. Finally, analyses are performed on several environmental conditions to investigate the long-term applicability of this multistep method. Wave loads are calculated using state-of-the-art theory, while wind loads are applied with a simplified model based on rotor thrust coefficients.

Keywords: fatigue damage, FORM, monopile, Monte Carlo, simulation, wind turbine

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Authors: A. Khodadadi, Hasani, Salehi

Abstract:

The advantages of using modified asphalt binders are widely recognized—primarily, improved rutting resistance, reduced fatigue cracking and less cold-temperature cracking. Nanoclays are known to enhance the properties of many polymers. Nanoclays are used to improve modulus and tensile strength, flame resistance and thermal and structural properties of many materials. This paper intends to investigate the application and development of nano-technological concepts for bituminous materials and asphalt pavements. The application of nano clay on the fatigue life of asphalt pavement have not been yet thoroughly understood. In this research, two type of highway asphalt materials, dense Marshall specimens, with 2% nano clay and without nano clay, were employed for the fatigue behavior of the asphalt pavement.The effect of nano additive on the performance of flexible pavements has been investigated through the indirect tensile test for the samples prepared with 2% nano clay and without nano clay in four stress levels from 200–500 kPa. The primary results indicated samples with 2% nano clay have almost double or even more fatigue life in most of stress levels.

Keywords: Nano clay, Asphalt, fatigue life, pavement

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Authors: Hassan Shahmiri Barzoki

Abstract:

Background: Posttraumatic stress disorder (PTSD) is an abnormal physiologic and psychological reaction in person with severe traumatic history. In recent studies, the relationship between PTSD and some other disease apparently unrelated to psychological situations, such as cardiovascular diseases, diabetes, and metabolic syndrome, has been revealed. Thus, the aim of this study was to survey the prevalence of metabolic syndrome and mental health in PTSD patients. Methods: The research design was retrospective cohort study. Subjects were consisted of 142 Iran-Iraq war veterans with PTSD (age: 40-60 years), and the control group was consisted of 153 veterans without PTSD. Data was collected using questionnaires, physical exams and laboratory tests. Results: Prevalence of metabolic syndrome was 45.1%in PTSD group and 17% in control group. In addition, blood pressure, triglyceride and fasting blood sugar in PTSD group were significantly higher than control group (p<0.05). Also, PTSD patients had significant high rates of psychiatric disorders. Conclusion: PTSD patients are more prone to metabolic syndrome and psychiatric disorders than control group.

Keywords: mental health, metabolic syndrome, post traumatic stress disorder, patient

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