Search results for: hospital room/wards
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 3493

Search results for: hospital room/wards

1483 A Comparative Study Mechanical Properties of Polytetrafluoroethylene Materials Synthesized by Non-Conventional and Conventional Techniques

Authors: H. Lahlali F. El Haouzi, A.M.Al-Baradi, I. El Aboudi, M. El Azhari, A. Mdarhri

Abstract:

Polytetrafluoroethylene (PTFE) is a high performance thermoplastic polymer with exceptional physical and chemical properties, such as a high melting temperature, high thermal stability, and very good chemical resistance. Nevertheless, manufacturing PTFE is problematic due to its high melt viscosity (10 12 Pa.s). In practice, it is by now well established that this property presents a serious problem when the classical methods are used to synthesized the dense PTFE materials in particularly hot pressing, high temperature extrusion. In this framework, we use here a new process namely spark plasma sintering (SPS) to elaborate PTFE samples from the micro metric particles powder. It consists in applying simultaneous electric current and pressure directly on the sample powder. By controlling the processing parameters of this technique, a series of PTFE samples are easy obtained and associated to remarkably short time as is reported in an early work. Our central goal in the present study is to understand how the non conventional SPS affects the mechanical properties at room temperature. For this end, a second commercially series of PTFE synthesized by using the extrusion method is investigated. The first data according to the tensile mechanical properties are found to be superior for the first set samples (SPS). However, this trend is not observed for the results obtained from the compression testing. The observed macro-behaviors are correlated to some physical properties of the two series of samples such as their crystallinity or density. Upon a close examination of these properties, we believe the SPS technique can be seen as a promising way to elaborate the polymer having high molecular mass without compromising their mechanical properties.

Keywords: PTFE, extrusion, Spark Plasma Sintering, physical properties, mechanical behavior

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1482 Physical-Mechanical Characteristics of Monocrystalline Si1-xGex(X 0,02) Solid Solutions

Authors: I. Kurashvili, A. Sichinava, G. Bokuchava, G. Darsavelidze

Abstract:

Si-Ge solid solutions (bulk poly- and monocrystalline samples, thin films) are characterized by high perspectives for application in semiconductor devices, in particular, optoelectronics and microelectronics. In this light complex studying of structural state of the defects and structural-sensitive physical properties of Si-Ge solid solutions depending on the contents of Si and Ge components is very important. Present work deals with the investigations of microstructure, electrophysical characteristics, microhardness, internal friction and shear modulus of Si1-xGex(x≤0,02) bulk monocrystals conducted at a room temperatures. Si-Ge bulk crystals were obtained by Czochralski method in [111] crystallographic direction. Investigated monocrystalline Si-Ge samples are characterized by p-type conductivity and carriers concentration 5.1014-1.1015cm-3, dislocation density 5.103-1.104cm-2, microhardness according to Vickers method 900-1200 Kg/mm2. Investigate samples are characterized with 0,5x0,5x(10-15) mm3 sizes, oriented along [111] direction at torsion oscillations ≈1Hz, multistage changing of internal friction and shear modulus has been revealed in an interval of strain amplitude of 10-5-5.10-3. Critical values of strain amplitude have been determined at which hysteretic changes of inelastic characteristics and microplasticity are observed. The critical strain amplitude and elasticity limit values are also determined. Tendency to decrease of dynamic mechanical characteristics is shown with increasing Ge content in Si-Ge solid solutions. Observed changes are discussed from the point of view of interaction of various dislocations with point defects and their complexes in a real structure of Si-Ge solid solutions.

Keywords: Microhardness, internal friction, shear modulus, Monocrystalline

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1481 Biomarkers in a Post-Stroke Population: Allied to Health Care in Brazil

Authors: Michael Ricardo Lang, AdriéLle Costa, Ivana Iesbik, Karine Haag, Leonardo Trindade Buffara, Oscar Reimann Junior, Chelin Auswaldt Steclan

Abstract:

Stroke affects not only the individual, but has significant impacts on the social and family context. Therefore, it is necessary to know the peculiarities of each region, in order to contribute to regional public health policies effectively. Thus, the present study discusses biomarkers in a post-stroke population, admitted to a stroke unit (U-stroke) of reference in the southern region of Brazil. Biomarkers were analyzed, such as age, length of stay, mortality rate, survival time, risk factors and family history of stroke in patients after ischemic stroke. In this studied population, comparing men and women, it was identified that men were more affected than women, and the average age of women affected was higher, as they also had the highest mortality rate and the shortest hospital stay. The risk factors identified here were according to the global scenario; with SAH being the most frequent and those associated with sedentary lifestyle in women the most frequent (dyspilipidemia, heart disease and obesity). In view of this, the importance of studies that characterize populations regionally is evident, strengthening the strategic planning of policies in favor of health care.

Keywords: biomarkers, sex, stroke, stroke unit, population

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1480 Fear and Anxiety among School Age Children Undergoing Dental Treatment in an Oral Health Unit

Authors: Maha Ibrahim Mohamed Khalifa

Abstract:

Background: Dental fear and anxiety lead to avoidance of dental treatment and deterioration of oral health. Aim of the study: To assess the levels of fear and anxiety among school-age children undergoing dental treatment. Setting: The study was conducted in Outpatient Dental Clinics at Benha Teaching Hospital. Research design: A descriptive research design was utilized to conduct the study. Sample: A purposive sample of 60 school-age children and their mothers attending at the previously mentioned setting was included. Tools: Three tools were used: Tool one: A structured interviewing questionnaire for Personal characteristics of children and their mothers. Tool two: Dental Subscale of Children's Fear Survey Schedule (CFSS-DS). Tool three: Modified Dental Anxiety Scale (MDAS). Results: It was illustrated that more than two-fifths (43.3%) of children had maximum fear and more than half of children (53.3%) had maximal anxiety. Conclusion: Many school-age children undergoing dental treatment suffer from high levels of fear and anxiety. Recommendations: The study recommended further research should be conducted to assess levels of fear and anxiety among children undergoing dental treatments and preferable nursing interventions for reducing their fears and anxieties.

Keywords: fear, anxiety, children, dental treatment

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1479 Unveiling the Self-Assembly Behavior and Salt-Induced Morphological Transition of Double PEG-Tailed Unconventional Amphiphiles

Authors: Rita Ghosh, Joykrishna Dey

Abstract:

PEG-based amphiphiles are of tremendous importance for its widespread applications in pharmaceutics, household purposes, and drug delivery. Previously, a number of single PEG-tailed amphiphiles having significant applications have been reported from our group. Therefore, it was of immense interest to explore the properties and application potential of PEG-based double tailed amphiphiles. Herein, for the first time, two novel double PEG-tailed amphiphiles having different PEG chain lengths have been developed. The self-assembly behavior of the newly developed amphiphiles in aqueous buffer (pH 7.0) was thoroughly investigated at 25 oC by a number of techniques including, 1H-NMR, and steady-state and time-dependent fluorescence spectroscopy, dynamic light scattering, transmission electron microscopy, atomic force microscopy, and isothermal titration calorimetry. Despite having two polar PEG chains both molecules were found to have strong tendency to self-assemble in aqueous buffered solution above a very low concentration. Surprisingly, the amphiphiles were shown to form stable vesicles spontaneously at room temperature without any external stimuli. The results of calorimetric measurements showed that the vesicle formation is driven by the hydrophobic effect (positive entropy change) of the system, which is associated with the helix-to-random coil transition of the PEG chain. The spectroscopic data confirmed that the bilayer membrane of the vesicles is constituted by the PEG chains of the amphiphilic molecule. Interestingly, the vesicles were also found to exhibit structural transitions upon addition of salts in solution. These properties of the vesicles enable them as potential candidate for drug delivery.

Keywords: double-tailed amphiphiles, fluorescence, microscopy, PEG, vesicles

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1478 Acute Kidney Injury in Severe Trauma Patients: Clinical Presentation and Risk Factor Analysis

Authors: Inkyong Yi

Abstract:

Acute kidney injury (AKI) in trauma patients is known to be associated with multiple factors, especially shock and consequent inadequate renal perfusion, yet its clinical presentation is little known in severe trauma patients. Our aim was to investigate the clinical presentation of acute kidney injury and its outcome in severe trauma patients at a level I trauma center. A total of 93 consecutive adult trauma patients with an injury severity score (ISS) of more than 15 were analyzed retrospectively from our Level I trauma center data base. Patients with direct renal injury were excluded. Patients were dichotomized into two groups, according to the presence of AKI. Various clinical parameters were compared between two groups, with Student’s T test and Mann-Whitney’s U test. The AKI group was further dichotomized into patients who recovered within seven days, and those who required more than 7days for recovery or those who did not recover at all. Various clinical parameters associated with outcome were further analyzed. Patients with AKI (n=33, 35%) presented with significantly higher age (61.4±17.3 vs. 45.4±17.3, p < 0.0001), incidence of comorbidities (hypertension; 51.5% vs. 13.3%, OR 6.906 95%CI 2.515-18.967, diabetes; 27.3% vs. 6.7%, OR 5.250, 95%CI 1.472-18.722), odds of head and neck trauma (69.7% vs. 41.7%, OR 3.220, 95%CI 1.306-7.942) and presence of shock during emergency room care (66.7% vs 21.7% OR 7.231, 95%CI, 2.798-18.687). Among AKI patients, patients who recovered within 1 week showed lower peak lactate (4.7mmol/L, 95%CI 2.9-6.5 vs 7.3mmol/L, 95%CI 5.0-9.6, p < 0.0287), lesser units of transfusion during first 24 hours (pRBC; 20.4unit, 95%CI 12.5-28.3 vs. 58.9unit, 95%CI 39.4-78.5, p=0.0003, FFP; 16.6unit, 95%CI 6.8-26.4 vs. 56.1unit, 95%CI 26.9-85.2, p=0.0027). In severe trauma patients, patients with AKI showed different clinical presentations and worse outcomes. Initial presence of shock and higher DIC profiles may be important risk factors for AKI in severe trauma patients. In patients with AKI, peak lactate level and amounts of transfusion are related to recovery.

Keywords: acute kidney injury, lactate, transfusion, trauma

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1477 Effectiveness of Homoeopathic Medicine Conium Maculatum 200 C for Management of Pyuria

Authors: Amir Ashraf

Abstract:

Homoeopathy is an alternative system of medicine discovered by German physician Samuel Hahnemann in 1796. It has been used by several people for various health conditions globally for more than last 200 years. In India, homoeopathy is considered as a major system of alternative medicine. Homoeopathy is found effective in various medical conditions including Pyuria. Pyuria is the condition in which pus cells are found in urine. Homoeopathy is very useful for reducing pus cells, and homeopathically potentized Conium Mac (Hemlock) is an important remedy commonly used for reducing pyuria. Aim: To reduce the amount pus cells found in urine using Conium Mac 200C. Methods: Design. Small N Design. Samples: Purposive Sampling with 5 cases diagnosed as pyuria. Tools: Personal Data Schedule and ICD-10 Criteria for Pyuria. Techniques: Potentized homoeopathic medicine, Conium Mac 200th potency is used. Statistical Analysis: The statistical analyses were done using non-parametric tests. Results: There is significant pre/post difference has been identified. Conclusion: Homoeopathic potency, Conium Mac 200 C is effective in reducing the increased level of pus cells found in urine samples.

Keywords: homoeopathy, alternative medicine, Pyuria, Conim Mac, small N design, non-parametric tests, homeopathic physician, Ashirvad Hospital, Kannur

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1476 Clinical Outcomes of Neonates Born to COVID-19 Positive Mothers in a Tertiary Level Private Hospital

Authors: Patricia Abigail B. Miranda, Imelda A. Luna

Abstract:

Introduction: COVID-19 infection is a novel viral illness that began as a local epidemic in December 2019 in Wuhan, China which quickly emerged into a pandemic by February 2020. The virus causes a spectrum of signs and symptoms, ranging from mild upper respiratory symptoms to acute respiratory distress syndrome, which may lead to death. Among children and neonates, those afflicted with the disease may present asymptomatically or with mild symptoms. To date, there has been limited local data that describes the outcomes of the growing number of COVID-19 cases, specifically in neonates. Methods: A cross-sectional study was conducted to determine the outcomes of neonates born to COVID-19 Positive Mothers from March 2020 until June 2022. The prevalence of COVID-19 among these neonates was also determined. Results: COVID-positive prevalence after 24 hours of life is at 8%, while prevalence after 48 hours among those who still underwent testing was at 13.51%. Moreover, among those COVID-19-negative neonates who had symptoms, they mostly presented with tachypnea (5.7%). The prevalence of complications among COVID-19-negative neonates delivered to COVID-19-positive mothers is 22.7%. Conclusion: Neonates born to COVID-19-positive mothers who yielded positive COVID-19 results are generally asymptomatic. Moreover, there are no associated mortalities among those who yielded positive results.

Keywords: COVID-19, neonates, outcomes, clinical profile

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1475 Prime Mover Sizing for Base-Loaded Combined Heating and Power Systems

Authors: Djalal Boualili

Abstract:

This article considers the problem of sizing prime movers for combined heating and power (CHP) systems operating at full load to satisfy a fraction of a facility's electric load, i.e. a base load. Prime mover sizing is examined using three criteria: operational cost, carbon dioxide emissions (CDE), and primary energy consumption (PEC). The sizing process leads to consider ratios of conversion factors applied to imported electricity to conversion factors applied to fuel consumed. These ratios are labelled RCost, R CDE, R PEC depending on whether the conversion factors are associated with operational cost, CDE, or PEC, respectively. Analytical results show that in order to achieve savings in operational cost, CDE, or PEC, the ratios must be larger than a unique constant R Min that only depends on the CHP components efficiencies. Savings in operational cost, CDE, or PEC due to CHP operation are explicitly formulated using simple equations. This facilitates the process of comparing the tradeoffs of optimizing the savings of one criterion over the other two – a task that has traditionally been accomplished through computer simulations. A hospital building, located in Chlef, Algeria, was used as an example to apply the methodology presented in this article.

Keywords: sizing, heating and power, ratios, energy consumption, carbon dioxide emissions

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1474 The Associations of Family Support with Sexual Behaviour and Repeat Induced Abortion among Chinese Adolescents

Authors: Jiashu Shen

Abstract:

Background: The abortion rate has increased significantly, which is harmful especially to adolescents, making repeat induced abortion (RIA) among adolescents a social problem. This study aims to investigate the associations of family support with sexual behavior and repeat induced abortion among Chinese adolescents Methods: This study based on a national hospital-based sample with 945 girls aged 15-19 who underwent induced abortion in 43 hospitals. Multivariate logistic regressions were performed to estimated odds ratio for the risk factors. Results: Adolescences living with parents were less inclined to undergo RIA, especially if they were rural (adjusted odds ratio=0.48 95%CI 0.31-0.72) and local (adjusted odds ratio =0.39 95%=0.23-0.66). Those with parental financial support were likely to have less sexual partnersand take contraceptives more regularly. Those with higher self-perceived importance in family were more likely to take contraceptives during the first sexual intercourse in higher age, and with higher first abortion age and less sexual partners. Conclusion: In mainland China, living with parents, parental financial support, high self-perceived importance in family and adequate family sexuality communications may contribute to lower incidence of RIA.

Keywords: Chinese adolescent, family support, repeat induced abortion, sexual behavior

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1473 Evaluation of Patients' Satisfaction Aspects in Governmental Egyptian Emergency Departments

Authors: N. Rashed, Z. Aysha, M. Fakher

Abstract:

Patient satisfaction is one of the core objectives of health care facilities. It is difficult to evaluate patients response in the emergency setting. The current study aimed to evaluate patients and family aspects of satisfaction in both adult and pediatric emergency departments and their recommendations for improvement. Cross-section survey(Brief Emergency department Patient Satisfaction Scale (BEPSS), was translated and validated, then performed to evaluate patients satisfaction in two governmental hospitals Emergency departments. Three hundred patients and their families were enrolled in the study. The waiting time in the adult Emergency department ranged from (5 minutes to 120 minutes), and most admissions were at the morning shift while at the pediatric hospital the waiting time ranged from 5 minutes to 100 minutes) and most admissions were at the afternoon shift. The results showed that the main domain of satisfaction in BEPSS in the adult emergency department was respecting the patients family while in the pediatric emergency department, the main domain was the nursing care about treatment. The main recommendation of improvement in pediatric Emergency Department was modifying the procedures while in adult Emergency Department was improving the training of physicians.

Keywords: emergency, department-patient, satisfaction-adult-pediatric

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1472 Yawning and Cortisol as a Potential Biomarker for Early Detection of Multiple Sclerosis

Authors: Simon B. N. Thompson

Abstract:

Cortisol is essential to the regulation of the immune system and yawning is a pathological symptom of multiple sclerosis (MS). Electromyography activity (EMG) in the jaw muscles typically rises when the muscles are moved and with yawning is highly correlated with cortisol levels in healthy people. Saliva samples from 59 participants were collected at the start and after yawning, or at the end of the presentation of yawning-provoking stimuli, in the absence of a yawn, together with EMG data and questionnaire data: Hospital Anxiety and Depression Scale, Yawning Susceptibility Scale, General Health Questionnaire, demographic, health details. Exclusion criteria: chronic fatigue, diabetes, fibromyalgia, heart condition, high blood pressure, hormone replacement therapy, multiple sclerosis, stroke. Significant differences were found between the saliva cortisol samples for the yawners, t (23) = -4.263, p = 0.000, as compared with the non-yawners between rest and post-stimuli, which was non-significant. Significant evidence was found to support the Thompson Cortisol Hypothesis suggesting that rises in cortisol levels are associated with yawning. Further research is exploring the use of cortisol as an early diagnostic tool for MS. Ethics approval granted and professional code of conduct, confidentiality, and safety issues are approved therein.

Keywords: cortisol, multiple sclerosis, yawning, thompson cortisol hypothesis

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1471 Determination of Alkali Treatment Conditions Effects That Influence the Variability of Kenaf Fiber Mean Cross-Sectional Area

Authors: Mohd Yussni Hashim, Mohd Nazrul Roslan, Shahruddin Mahzan Mohd Zin, Saparudin Ariffin

Abstract:

Fiber cross-sectional area value is a crucial factor in determining the strength properties of natural fiber. Furthermore, unlike synthetic fiber, a diameter and cross-sectional area of natural fiber has a large variation along and between the fibers. This study aims to determine the main and interaction effects of alkali treatment conditions that influence kenaf bast fiber mean cross-sectional area. Three alkali treatment conditions at two different levels were selected. The conditions setting were alkali concentrations at two and ten w/v %; fiber immersed temperature at room temperature and 1000C; and fiber immersed duration for 30 and 480 minute. Untreated kenaf fiber was used as a control unit. Kenaf bast fiber bundle mounting tab was prepared according to ASTM C1557-03. The cross-sectional area was measured using a Leica video analyzer. The study result showed that kenaf fiber bundle mean cross-sectional area was reduced 6.77% to 29.88% after alkali treatment. From the analysis of variance, it shows that the interaction of alkali concentration and immersed time has a higher magnitude at 0.1619 compared to alkali concentration and immersed temperature interaction that was 0.0896. For the main effect, alkali concentration factor contributes to the higher magnitude at 0.1372 which indicated the decrease pattern of variability when the level changed from lower to the higher level. Then, it was followed by immersed temperature at 0.1261 and immersed time at 0.0696 magnitudes.

Keywords: natural fiber, kenaf bast fiber bundles, alkali treatment, cross-sectional area

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1470 An Assessment of the Hip Muscular Imbalance for Patients with Rheumatism

Authors: Anthony Bawa, Konstantinos Banitsas

Abstract:

Rheumatism is a muscular disorder that affects the muscles of the upper and lower limbs. This condition could potentially progress to impair the movement of patients. This study aims to investigate the hip muscular imbalance in patients with chronic rheumatism. A clinical trial involving a total of 15 participants, made up of 10 patients and 5 control subjects, took place in KATH Hospital between August and September. Participants recruited for the study were of age 54 ± 8years, weight 65± 8kg, and height 176 ± 8cm. Muscle signals were recorded from the rectus femoris, and vastus lateralis on the right and left hip of participants. The parameters used in determining the hip muscular imbalances were the maximum voluntary contraction (MVC%), the mean difference, and hip muscle fatigue levels. The mean signals were compared using a t-test, and the metrics for muscle fatigue assessment were based on the root mean square (RMS), mean absolute value (MAV) and mean frequency (MEF), which were computed between the hip muscles of participants. The results indicated that there were significant imbalances in the muscle coactivity between the right and left hip muscles of patients. The patients’ MVC values were observed to be above 10% when compared with control subjects. Furthermore, the mean difference was seen to be higher with p > 0.002 among patients, which indicated clear differences in the hip muscle contraction activities. The findings indicate significant hip muscular imbalances for patients with rheumatism compared with control subjects. Information about the imbalances among patients will be useful for clinicians in designing therapeutic muscle-strengthening exercises.

Keywords: muscular, imbalances, rheumatism, Hip

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1469 Positive effect of Cu2+ and Ca2+ on the Thermostability of Bambara Groundnut Peroxidase A6, and its Catalytic Efficiency Toward the Oxidation of 3,3,5,5 -Tetramethyl Benzidine

Authors: Yves Mann Elate Lea Mbassi, Marie Solange Evehe Bebandoue, Wilfred Fon Mbacham

Abstract:

Improving the catalytic performance of enzymes has been a long-standing theme of analytical biochemistry research. Induction of peroxidase activity by metals is a common reaction in higher plants. We thought that this increase in peroxidase activity may be due, on the one hand, to the stimulation of the gene expression of these enzymes but also to a modification of their chemical reactivity following the binding of some metal ions on their active site. We tested the effect of some metal salts (MgCl₂, MnCl₂, ZnCl₂, CaCl₂ and CuSO₄) on the activity and thermostability of peroxidase A6, a thermostable peroxidase that we discovered and purified in a previous study. The chromogenic substrate used was 3,3′,5,5′-tetramethylbenzidine. Of all the metals tested for their effect on A6, only magnesium and copper had a significant effect on the activity of the enzyme at room temperature. The Mann-Whitney test shows a slight inhibitory effect of activity by the magnesium salt (P = 0.043), while the activity of the enzyme is 5 times higher in the presence of the copper salt (P = 0.002). Moreover, the thermostability of peroxidase A6 is increased when calcium and copper salts are present. The activity in the presence of CaCl₂ is 8 times higher than the residual activity of the enzyme alone after incubation at 80°C for 10 min and 35 times higher in the presence of CuSO4 under the same conditions. In addition, manganese and zinc salts slightly reduce the thermostability of the enzyme. The activity and structural stability of peroxidase A6 can clearly be activated by Cu₂+, which therefore enhance the oxidation of 3,3′,5,5′-tetramethylbenzidine, which was used in this study as a chromogenic substrate. Ca₂+ likely has a more stabilizing function for the catalytic site.

Keywords: peroxidase activity, copper ions, calcium ions, thermostability

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1468 Surface Nanostructure Developed by Ultrasonic Shot Peening and Its Effect on Low Cycle Fatigue Life of the IN718 Superalloy

Authors: Sanjeev Kumar, Vikas Kumar

Abstract:

Inconel 718 (IN718) is a high strength nickel-based superalloy designed for high-temperature applications up to 650 °C. It is widely used in gas turbines of jet engines and related aerospace applications because of its good mechanical properties and structural stability at elevated temperatures. Because of good performance ratio and excellent process capability, this alloy has been used predominantly for aeronautic engine components like compressor disc and compressor blade. The main precipitates that contribute to high-temperature strength of IN718 are γʹ Ni₃(Al, Ti) and mainly γʹʹ (Ni₃ Nb). Various processes have been used for modification of the surface of components, such as Laser Shock Peening (LSP), Conventional Shot Peening (SP) and Ultrasonic Shot Peening (USP) to induce compressive residual stress (CRS) and development of fine-grained structure in the surface region. Surface nanostructure by ultrasonic shot peening is a novel methodology of surface modification to improve the overall performance of structural components. Surface nanostructure was developed on the peak aged IN718 superalloy using USP and its effect was studied on low cycle fatigue (LCF) life. Nanostructure of ~ 49 to 73 nm was developed in the surface region of the alloy by USP. The gage section of LCF samples was USPed for 5 minutes at a constant frequency of 20 kHz using StressVoyager to modify the surface. Strain controlled cyclic tests were performed for non-USPed and USPed samples at ±Δεt/2 from ±0.50% to ±1.0% at strain rate (ė) 1×10⁻³ s⁻¹ under reversal loading (R=‒1) at room temperature. The fatigue life of the USPed specimens was found to be more than that of the non-USPed ones. LCF life of the USPed specimen at Δεt/2=±0.50% was enhanced by more than twice of the non-USPed specimen.

Keywords: IN718 superalloy, nanostructure, USP, LCF life

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1467 A Preliminary Report of HBV Full Genome Sequencing Derived from Iranian Intravenous Drug Users

Authors: Maryam Vaezjalali, Koroush Rahimian, Maryam Asli, Tahmineh Kandelouei, Foad Davoodbeglou, Amir H. Kashi

Abstract:

Objectives: The present study was conducted to assess the HBV molecular profiles including genotypes, subgenotypes, subtypes & mutations in hepatitis B genes. Materials/Patients and Methods: This study was conducted on 229 intravenous drug users who referred to three Drop- in-Centers and a hospital in Tehran. HBV DNA was extracted from HBsAg positive serum samples and amplified by Nested PCR. HBV genotype, subgenotypes, subtype and genes mutation were determined by direct sequencing. Phylogenetic tree was constructed using neighbor- joining (NJ) method. Statistical analyses were carried out by SPSS 20. Results: HBV DNA was found in 3 HBsAg positive cases. Phylogenetic tree of derived HBV DNAs showed the existence of genotype D (subgenotype D1, subtype ayw2). Also immune escape mutations were determined in S gene. Conclusion: There were a few variations and genotypes and subtypes among infected intravenous drug users. This study showed the predominance of genotype D among intravenous drug users. Our study concurs with other reports from Iran, that all showing currently only genotype D is the only detectable genotype in Iran.

Keywords: drug users, genotype, HBV, phylogenetic tree

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1466 BiFeO3-CoFe2O4-PbTiO3 Composites: Structural, Multiferroic and Optical Characteristics

Authors: Nidhi Adhlakha, K. L. Yadav

Abstract:

Three phase magnetoelectric (ME) composites (1-x)(0.7BiFeO3-0.3CoFe2O4)-xPbTiO3 (or equivalently written as (1-x)(0.7BFO-0.3CFO)-xPT) with x variations 0, 0.30, 0.35, 0.40, 0.45 and 1.0 were synthesized using hybrid processing route. The effects of PT addition on structural, multiferroic and optical properties have been subsequently investigated. A detailed Rietveld refinement analysis of X-ray diffraction patterns has been performed, which confirms the presence of structural phases of individual constituents in the composites. Field emission scanning electron microscopy (FESEM) images are taken for microstructural analysis and grain size determination. Transmission electron microscopy (TEM) analysis of 0.3CFO-0.7BFO reveals the average particle size to be lying in the window of 8-10 nm. The temperature dependent dielectric constant at various frequencies (1 kHz, 10 kHz, 50 kHz, 100 kHz and 500 kHz) has been studied and the dielectric study reveals that the increase of dielectric constant and decrease of average dielectric loss of composites with incorporation of PT content. The room temperature ferromagnetic behavior of composites is confirmed through the observation of Magnetization vs. Magnetic field (M-H) hysteresis loops. The variation of magnetization with temperature indicates the presence of spin glass behavior in composites. Magnetoelectric coupling is evidenced in the composites through the observation of the dependence of the dielectric constant on the magnetic field, and magnetodielectric response of 2.05 % is observed for 45 mol% addition of PT content. The fractional change of magnetic field induced dielectric constant can also be expressed as ∆ε_r~γM^2 and the value of γ is found to be ~1.08×10-2 (emu/g)-2 for composite with x=0.40. Fourier transformed infrared (FTIR) spectroscopy of samples is carried out to analyze various bonds formation in the composites.

Keywords: composite, X-ray diffraction, dielectric properties, optical properties

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1465 Heart Rate Variability Responses Pre-, during, and Post-Exercise among Special Olympics Athletes

Authors: Kearney Dover, Viviene Temple, Lynneth Stuart-Hill

Abstract:

Heart Rate Variability (HRV) is the beat-to-beat variation in adjacent heartbeats. HRV is a non-invasive measure of the autonomic nervous system (ANS) and provides information about the sympathetic (SNS) and parasympathetic (PNS) nervous systems. The HRV of a well-conditioned heart is generally high at rest, whereas low HRV has been associated with adverse outcomes/conditions, including congestive heart failure, diabetic neuropathy, depression, and hospital admissions. HRV has received very little research attention among individuals with intellectual disabilities in general or Special Olympic athletes. Purpose: 1) Having a longer post-exercise rest and recovery time to establish how long it takes for the athletes’ HRV components to return to pre-exercise levels, 2) To determine if greater familiarization with the testing processes influences HRV. Participants: Two separate samples of 10 adult Special Olympics athletes will be recruited for 2 separate studies. Athletes will be between 18 and 50 years of age and will be members of Special Olympics BC. Anticipated Findings: To answer why the Special Olympics athletes display poor cardiac responsiveness to changes in autonomic modulation during exercise. By testing the cortisol levels in the athletes, we can determine their stress levels which will then explain their measured HRV.

Keywords: 6MWT, autonomic modulation, cortisol levels, intellectual disability

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1464 Skin Manifestations in Children With Inborn Errors of Immunity in a Tertiary Care Hospital in Iran

Authors: Zahra Salehi Shahrbabaki, Zahra Chavoshzadeh, Fahimeh Abdollahimajd, Samin Sharafian, Tolue Mahdavi, Mahnaz Jamee

Abstract:

Background: Inborn errors of immunity (IEIs) are monogenic diseases of the immune the system with broad clinical manifestations. Despite the increasing genetic advancements, the diagnosis of IEIs still leans on clinical diagnosis. Dermatologic manifestations are observed in a large number of IEI patients and can lead to proper approach, prompt intervention and improved prognosis. Methods: This cross-sectional study was carried out between 2018 and 2020 on IEIs at a Children's tertiary care center in Tehran, Iran. Demographic details (including age, sex, and parental consanguinity), age at onset of symptoms and family history of IEI with were recorded. Results :212 patients were included. Cutaneous findings were reported in (95 ,44.8%) patients. and 61 of 95 (64.2%) reported skin lesions as the first clinical presentation. Skin infection (69, 72.6%) was the most frequent cutaneous manifestation, followed by an eczematous rash (24, 25 %). Conclusions: Skin manifestations are common feature in IEI patients and can be readily recognizable by healthcare providers. This study tried to provide information on prognostic consequences.

Keywords: primary immuno deficiency, inborn errror of metabolism, skin manifestation, skin infection

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1463 A Refrigerated Condition for the Storage of Glucose Test Strips at Health Promoting Hospitals: An Implication for Hospitals with Limited Air Conditioners

Authors: Wanutchaya Duanginta, Napaporn Apiratmateekul, Tippawan Sangkaew, Sunaree Wekinhirun, Kunchit Kongros, Wanvisa Treebuphachatsakul

Abstract:

Thailand has a tropical climate with an average outdoor ambient air temperature of over 30°C, which can exceed manufacturer recommendations for the storage of glucose test strips. This study monitored temperature and humidity at actual sites of five sub-district health promoting hospitals (HPH) in Phitsanulok Province for the storage of glucose test strips in refrigerated conditions. Five calibrated data loggers were placed at the actual sites for glucose test strip storage at five HPHs for 8 weeks between April and June. For the stress test, two lot numbers of glucose test strips, each with two glucose meters, were kept in a plastic box with desiccants and placed in a refrigerator with the temperature calibrated to 4°C and at room temperature (RT). Temperature and humidity in the refrigerator and at RT were measured every hour for 30 days. The mean temperature for storing test strips at the five HPHs ranged from 29°C to 33°C, and three of the five HPHs (60%) had a mean temperature above 30°C. The refrigerator temperatures were 3.8 ± 2.0°C (2.0°C to 6.5°C), and relative humidity was 51 ± 2% (42 to 54%). The maximum of blood glucose testing by glucose meters when the test strips were stored in a refrigerator were not significantly different (p > 0.05) from unstressed test strips for both glucose meters using amperometry-GDH-PQQ and amperometry-GDH-FAD principles. Opening the test strip vial daily resulted in higher variation than when refrigerated after a single-use. However, the variations were still within an acceptable range. This study concludes that glucose tested strips can be stored in plastic boxes in a refrigerator if it is well-controlled for temperature and humidity. Storage of glucose-tested strips in the refrigerator during hot and humid weather may be useful for HPHs with limited air conditioners.

Keywords: environmental stressed test, thermal stressed test, quality control, point-of-care testing

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1462 Environmental Fatigue Analysis for Control Rod Drive Mechanisms Seal House

Authors: Xuejiao Shao, Jianguo Chen, Xiaolong Fu

Abstract:

In this paper, the elastoplastic strain correction factor computed by software of ANSYS was modified, and the fatigue usage factor in air was also corrected considering in water under reactor operating condition. The fatigue of key parts on control rod drive mechanisms was analyzed considering the influence of environmental fatigue caused by the coolant in the react pressure vessel. The elastoplastic strain correction factor was modified by analyzing thermal and mechanical loads separately referring the rules of RCC-M 2002. The new elastoplastic strain correction factor Ke(mix) is computed to replace the original Ke computed by the software of ANSYS when evaluating the fatigue produced by thermal and mechanical loads together. Based on the Ke(mix) and the usage cycle and fatigue design curves, the new range of primary plus secondary stresses was evaluated to obtain the final fatigue usage factor. The results show that the precision of fatigue usage factor can be elevated by using modified Ke when the amplify of the primary and secondary stress is large to some extent. One approach has been proposed for incorporating the environmental effects considering the effects of reactor coolant environments on fatigue life in terms of an environmental correction factor Fen, which is the ratio of fatigue life in air at room. To incorporate environmental effects into the RCCM Code fatigue evaluations, the fatigue usage factor based on the current Code design curves is multiplied by the correction factor. The contribution of environmental effects to results is discussed. Fatigue life decreases logarithmically with decreasing strain rate below 10%/s, which is insensitive to strain rate when temperatures below 100°C.

Keywords: environmental fatigue, usage factor, elastoplastic strain correction factor, environmental correction

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1461 Rapid-Access Multispecialty Nurse-Led Tongue Tie Service: A Retrospective Evaluation of Cost-Effectiveness

Authors: Jia Yin Tan, Daniel Rambei, Kate Mann, Samuel price, Ahmed Aboelela

Abstract:

Introduction: Breastfeeding is a complex process, influenced by various factors. Tongue-tie may lead to breastfeeding difficulties due to an inability to suck effectively, causing sore nipples and poor infant weight gain. In the UK, most frenotomies on infants are performed by doctors, nurses, health visitors or midwives. Objectives: Evaluation of safety and efficacy of a multispecialty nurse-led rapid access tongue-tie service at Sheffield Children’s Hospital, run jointly by the ENT and paediatric surgery departments. Methodology: A retrospective observational study, including all patients attending the ENT and paediatric surgery nurse-led tongue tie clinics between 1/10/2021 and 30/09/2022. Results: During the study period there were 1135 referrals for frenotomy, with a mean of 15 days between referral to clinic episode. 86.8% of referred patients underwent frenotomy, with a complication rate of 0.1% and revision rate of 5.4%. Conclusions: Our findings suggest that our rapid access nurse-led outpatient tongue tie service is safe and efficacious, with low complication and revision rates. This suggests a potential for developing a community-based service, allowing safe and effective care closer to home.

Keywords: tongue tie, frenotomy, cost, nurse-led

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1460 Meningeal Hemangiopericytoma in an HIV-Positive Patient: A Case Report and Review of Literature

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

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

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

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1459 Distribution of Gamma-Radiation Levels in Core Sediment Samples in Gulf of İzmir, Eastern Aegean Sea, Turkey

Authors: D. Kurt, İ. F. Barut, Z. Ü. Yümün, E. Kam

Abstract:

After development of the industrial revolution, industrial plants and settlements have spread widely on the sea coasts. This concentration also brings environmental pollution in the sea. This study focuses on the Gulf of İzmir where is located in West of Turkey and it is a fascinating natural gulf of the Eastern Aegean Sea. Investigating marine current sediment is extremely important to detect pollution. Natural radionuclides’ pollution of the marine environment which is also known as a significant environmental anxiety. Ground drilling cores (the depth of each sediment is variant) were collected from the Gulf of İzmir’s four different locations which were Karşıyaka, İnciraltı, Çeşmealtı and Bayraklı. These sediment cores were put in preserving bags with weight around 1 kg, and they were dried at room temperature in a week for moisture removal. Then, they were sieved with 1 mm sieve holes, and finally these powdered samples were relocation to polyethylene Marinelli beakers of 100 ml versions. Each prepared sediment was waited to reach radioactive equilibrium between uranium and thorium for 40 days. Gamma spectrometry measurements were settled using a HPG (High- Purity Germanium) semiconductor detector. Semiconductor detectors are very good at separating power of the energy, they are easily able to differentiate peaks that are pretty close to each other. That is why, gamma spectroscopy’s usage is common for the determination of the activities of U - 238, Th - 232, Ra - 226, Cr - 137 and K - 40 in Bq kg⁻¹. In this study, the results display that the average concentrations of activities’ values are in respectively; 2.2 ± 1.5 Bq/ kg⁻¹, 0.98 ± 0.02 Bq/ kg⁻¹, 8 ± 0.96 Bq/ kg⁻¹, 0.93 ± 0.14 Bq/ kg⁻¹, and 76.05 ± 0.93 Bq/ kg⁻¹. The outcomes of the study are able to be used as a criterion for forthcoming research and the obtained data would be pragmatic for radiological mapping of the precise areas.

Keywords: gamma, Gulf of İzmir (Eastern Aegean Sea-Turkey), natural radionuclides, pollution

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1458 Data-Driven Approach to Predict Inpatient's Estimated Discharge Date

Authors: Ayliana Dharmawan, Heng Yong Sheng, Zhang Xiaojin, Tan Thai Lian

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To facilitate discharge planning, doctors are presently required to assign an Estimated Discharge Date (EDD) for each patient admitted to the hospital. This assignment of the EDD is largely based on the doctor’s judgment. This can be difficult for cases which are complex or relatively new to the doctor. It is hypothesized that a data-driven approach would be able to facilitate the doctors to make accurate estimations of the discharge date. Making use of routinely collected data on inpatient discharges between January 2013 and May 2016, a predictive model was developed using machine learning techniques to predict the Length of Stay (and hence the EDD) of inpatients, at the point of admission. The predictive performance of the model was compared to that of the clinicians using accuracy measures. Overall, the best performing model was found to be able to predict EDD with an accuracy improvement in Average Squared Error (ASE) by -38% as compared to the first EDD determined by the present method. It was found that important predictors of the EDD include the provisional diagnosis code, patient’s age, attending doctor at admission, medical specialty at admission, accommodation type, and the mean length of stay of the patient in the past year. The predictive model can be used as a tool to accurately predict the EDD.

Keywords: inpatient, estimated discharge date, EDD, prediction, data-driven

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1457 Uterine Leiomyomas and Urological Complications

Authors: Dharshini Selvarajah, Nicula Lui, Karen Kong

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Background: Uterine fibroids are a common benign gynaecologic neoplasm in reproductive-aged women. Fibroids may become symptomatic in a vast majority of nulliparous women. Their diagnosis and management is often coordinated between gyneacologists, radiologists and urologists depending on the anatomical location, growth, size and the fibroids sarcomatous evolvement. Some patients may develop obstructive uropathy symptoms, either uni or bilateral secondary urethral obstruction causing hydronephrosis. Uterine artery emoblisation (UAE) has previously shown to effectively resolve symptoms as well as relieve urethral obstruction and resolve the hydronephrosis. UAE has now established itself as an organ preserving and minimally invasive procedure in the management of symptomatic uterine fibroids. It is a safe and effective alternative to hysterectomy for resolving fibroid related pressure symptoms. The case presented examines the clinical manifestations and impact of uterine fibroids on the urinary tract system. The therapeutic options to relieve the urological symptoms as well as preserve fertility are explored and presented. Case: The case is a 29-year-old Nepalese female admitted to hospital with recurrent urosepsis with multiresistant organisms. This was on a background of an enlarged uterus (measuring 17cm x11cm) with multiple subserosal, intramural and exophytic fibroids- causing external ureteric compression. She had bilateral ureteric stents insitu and required bilateral right and left nephrostomies during repeated episodes of urosepsis and bilateral ureteric obstruction. The left nephrostomy was removed a month prior to admission and her most recent CT KUB demonstrated hypofunctioning ureteric stents with bilateral hydronephrosis. Options of hysterectomy versus uterine artery emoblisation (UAE) were extensively explored. The patient was keen to preserve fertility. Risks associated with UAE such as expulsion of the submucosal component of the fibroids and the possibilities of sepsis in the setting of ongoing ureteric colonisation were particularly high. The patient opted to trial UAE even though the risks of recurrent hospital admissions with urosepsis were going to be particularly high. In the event, the uterus fails to shrink adequately enough to relieve the obstructed ureters a hysterectomy would inevitably be required in future. Day 3 post UAE the patient developed fevers, was hypotensive and tachycardic post-receiving prophylactic meropenem and fluconazole pre emoblisation. She was noted to have a CRP of 293 with the most recent urine culture during this time growing Candida albicans. The patient was recommenced on oral fluconazole and IV meropenem, with good effect. Her repeat renal tract ultrasound post-UAE showed ongoing marked left hydronephrosis relatively unchanged from the scan one month prior to the procedure, however the right-sided hydronephrosis had resolved. The patient was discharged on a 2-week course of antibiotics. The patient will have a repeat renal tract ultrasound and MRI of the ureters to re-evaluate the degree of hydronephrosis and progress- this was unavailable at the time of abstract submission and will be presented at the conference. Conclusion: Fibroids are a common benign tumour of the uterus and can frequently impact the lower urinary system resulting in significant uropathy. They often enlarge and compress the urinary bladder, urethra and lower end of the ureters. The effectiveness of UAE as a fertility preserving option is described.

Keywords: Uterine leiomyomas and urological complications, uterine artery embolisation for fibroids, Uterine fibroids and complications, Management of uterine fibroids

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1456 Role of Dedicated Medical Social Worker in Fund Mobilisation and Economic Evaluation in Ovarian Cancer: Experience from a Tertiary Referral Centre in Eastern India

Authors: Aparajita Bhattacharya, Mousumi Dutta, Zakir Husain, Dionne Sequeira, Asima Mukhopadhyay

Abstract:

Background: Tata Medical Centre (TMC), Kolkata is a major cancer referral centre in Eastern India and neighbouring countries providing state of the art facilities; however, it is a non-profit organisation with patients requiring to pay at subsidised rates. Although a system for social assessment and applying for governmental/ non-governmental (NGO) funds is in place, access is challenging. Amongst gynaecological cancers (GC), ovarian cancer (OC) is associated with the highest treatment cost; majority of which is required at the beginning when complex surgery is performed and funding arrangements cannot be made in time. We therefore appointed a dedicated Medical Social Worker (MSW) in 2016, supported by NGO for GC patients in order to assist patients/family members to access/avail these funds more readily and assist in economic evaluation for both direct and opportunity costs. Objectives: To reflect on our experience and challenges in collecting data on economic evaluation of cancer patients and compare success rates in achieving fund mobilization after introduction of MSW. Methods: A Retrospective survey. Patients with OC and their relatives were seen by the MSW during the initial outpatients department visit and followed though till discharge from the hospital and during follow-up visits. Assistance was provided in preparing the essential documents/paperwork/contacts for the funding agencies including both governmental (Chief-Minister/Prime-Minister/President) and NGO sources. In addition, a detailed questionnaire was filled up for economic assessment of direct/opportunity costs during the entire treatment and 12 months follow up period which forms a part of the study called HEPTROC (Health economic evaluation of primary treatment for ovarian cancer) developed in collaboration with economics departments of Universities. Results: In 2015, 102 patients were operated for OC; only 16 patients (15.68 %) had availed funding of a total sum of INR 1640000 through the hospital system for social assessment. Following challenges were faced by majority of the relatives: 1. Gathering important documents/proper contact details for governmental funding bodies and difficulty in following up the current status 3. Late arrival of funds. In contrast in 2016, 104 OC patients underwent surgery; the direct cost of treatment was significantly higher (median, INR 300000- 400000) compared to other GCs (n=274). 98/104 (94.23%) OC patients could be helped to apply for funds and 90/104(86.56%) patients received funding amounting to a total of INR 10897000. There has been a tenfold increase in funds mobilized in 2016 after the introduction of dedicated MSW in GC. So far, in 2017 (till June), 46/54(85.18%) OC patients applied for funds and 37/54(68.51%) patients have received funding. In a qualitative survey, all patients appreciated the role of the MSW who subsequently became the key worker for patient follow up and the chief portal for patient reported outcome monitoring. Data collection quality for the HEPTROC study was improved when questionnaires were administered by the MSW compared to researchers. Conclusion: Introduction of cancer specific MSW can expedite the availability of funds required for cancer patients and it can positively impact on patient satisfaction and outcome reporting. The economic assessment will influence fund allocation and decision for policymaking in ovarian cancer. Acknowledgement: Jivdaya Foundation Dallas, Texas.

Keywords: economic evaluation, funding, medical social worker, ovarian cancer

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1455 Effect of High-Energy Ball Milling on the Electrical and Piezoelectric Properties of (K0.5Na0.5)(Nb0.9Ta0.1)O3 Lead-Free Piezoceramics

Authors: Chongtham Jiten, K. Chandramani Singh, Radhapiyari Laishram

Abstract:

Nanocrystalline powders of the lead-free piezoelectric material, tantalum-substituted potassium sodium niobate (K0.5Na0.5)(Nb0.9Ta0.1)O3 (KNNT), were produced using a Retsch PM100 planetary ball mill by setting the milling time to 15h, 20h, 25h, 30h, 35h and 40h, at a fixed speed of 250rpm. The average particle size of the milled powders was found to decrease from 12nm to 3nm as the milling time increases from 15h to 25h, which is in agreement with the existing theoretical model. An anomalous increase to 98nm and then a drop to 3nm in the particle size were observed as the milling time further increases to 30h and 40h respectively. Various sizes of these starting KNNT powders were used to investigate the effect of milling time on the microstructure, dielectric properties, phase transitions and piezoelectric properties of the resulting KNNT ceramics. The particle size of starting KNNT was somewhat proportional to the grain size. As the milling time increases from 15h to 25h, the resulting ceramics exhibit enhancement in the values of relative density from 94.8% to 95.8%, room temperature dielectric constant (εRT) from 878 to 1213, and piezoelectric charge coefficient (d33) from 108pC/N to 128pC/N. For this range of ceramic samples, grain size refinement suppresses the maximum dielectric constant (εmax), shifts the Curie temperature (Tc) to a lower temperature and the orthorhombic-tetragonal phase transition (Tot) to a higher temperature. Further increase of milling time from 25h to 40h produces a gradual degradation in the values of relative density, εRT, and d33 of the resulting ceramics.

Keywords: perovskite, dielectric, ceramics, high-energy milling

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1454 Burkholderia Cepacia ST 767 Causing a Three Years Nosocomial Outbreak in a Hemodialysis Unit

Authors: Gousilin Leandra Rocha Da Silva, Stéfani T. A. Dantas, Bruna F. Rossi, Erika R. Bonsaglia, Ivana G. Castilho, Terue Sadatsune, Ary Fernandes Júnior, Vera l. M. Rall

Abstract:

Kidney failure causes decreased diuresis and accumulation of nitrogenous substances in the body. To increase patient survival, hemodialysis is used as a partial substitute for renal function. However, contamination of the water used in this treatment, causing bacteremia in patients, is a worldwide concern. The Burkholderia cepacia complex (Bcc), a group of bacteria with more than 20 species, is frequently isolated from hemodialysis water samples and comprises opportunistic bacteria, affecting immunosuppressed patients, due to its wide variety of virulence factors, in addition to innate resistance to several antimicrobial agents, contributing to the permanence in the hospital environment and to the pathogenesis in the host. The objective of the present work was to characterize molecularly and phenotypically Bcc isolates collected from the water and dialysate of the Hemodialysis Unit and from the blood of patients at a Public Hospital in Botucatu, São Paulo, Brazil, between 2019 and 2021. We used 33 Bcc isolates, previously obtained from blood cultures from patients with bacteremia undergoing hemodialysis treatment (2019-2021) and 24 isolates obtained from water and dialysate samples in a Hemodialysis Unit (same period). The recA gene was sequenced to identify the specific species among the Bcc group. All isolates were tested for the presence of some genes that encode virulence factors such as cblA, esmR, zmpA and zmpB. Considering the epidemiology of the outbreak, the Bcc isolates were molecularly characterized by Multi Locus Sequence Type (MLST) and by pulsed-field gel electrophoresis (PFGE). The verification and quantification of biofilm in a polystyrene microplate were performed by submitting the isolates to different incubation temperatures (20°C, average water temperature and 35°C, optimal temperature for group growth). The antibiogram was performed with disc diffusion tests on agar, using discs impregnated with cefepime (30µg), ceftazidime (30µg), ciprofloxacin (5µg), gentamicin (10µg), imipenem (10µg), amikacin 30µg), sulfametazol/trimethoprim (23.75/1.25µg) and ampicillin/sulbactam (10/10µg). The presence of ZmpB was identified in all isolates, while ZmpA was observed in 96.5% of the isolates, while none of them presented the cblA and esmR genes. The antibiogram of the 33 human isolates indicated that all were resistant to gentamicin, colistin, ampicillin/sulbactam and imipenem. 16 (48.5%) isolates were resistant to amikacin and lower rates of resistance were observed for meropenem, ceftazidime, cefepime, ciprofloxacin and piperacycline/tazobactam (6.1%). All isolates were sensitive to sulfametazol/trimethoprim, levofloxacin and tigecycline. As for the water isolates, resistance was observed only to gentamicin (34.8%) and imipenem (17.4%). According to PFGE results, all isolates obtained from humans and water belonged to the same pulsotype (1), which was identified by recA sequencing as B. cepacia¸, belonging to sequence type ST-767. By observing a single pulse type over three years, one can observe the persistence of this isolate in the pipeline, contaminating patients undergoing hemodialysis, despite the routine disinfection of water with peracetic acid. This persistence is probably due to the production of biofilm, which protects bacteria from disinfectants and, making this scenario more critical, several isolates proved to be multidrug-resistant (resistance to at least three groups of antimicrobials), turning the patient care even more difficult.

Keywords: hemodialysis, burkholderia cepacia, PFGE, MLST, multi drug resistance

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