Search results for: materials chemistry
747 Dual-Phase High Entropy (Ti₀.₂₅V₀.₂₅Zr₀.₂₅Hf₀.₂₅) BxCy Ceramics Produced by Spark Plasma Sintering
Authors: Ana-Carolina Feltrin, Daniel Hedman, Farid Akhtar
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High entropy ceramic (HEC) materials are characterized by their compositional disorder due to different metallic element atoms occupying the cation position and non-metal elements occupying the anion position. Several studies have focused on the processing and characterization of high entropy carbides and high entropy borides, as these HECs present interesting mechanical and chemical properties. A few studies have been published on HECs containing two non-metallic elements in the composition. Dual-phase high entropy (Ti₀.₂₅V₀.₂₅Zr₀.₂₅Hf₀.₂₅)BxCy ceramics with different amounts of x and y, (0.25 HfC + 0.25 ZrC + 0.25 VC + 0.25 TiB₂), (0.25 HfC + 0.25 ZrC + 0.25 VB2 + 0.25 TiB₂) and (0.25 HfC + 0.25 ZrB2 + 0.25 VB2 + 0.25 TiB₂) were sintered from boride and carbide precursor powders using SPS at 2000°C with holding time of 10 min, uniaxial pressure of 50 MPa and under Ar atmosphere. The sintered specimens formed two HEC phases: a Zr-Hf rich FCC phase and a Ti-V HCP phase, and both phases contained all the metallic elements from 5-50 at%. Phase quantification analysis of XRD data revealed that the molar amount of hexagonal phase increased with increased mole fraction of borides in the starting powders, whereas cubic FCC phase increased with increased carbide in the starting powders. SPS consolidated (Ti₀.₂₅V₀.₂₅Zr₀.₂₅Hf₀.₂₅)BC0.5 and (Ti₀.₂₅V₀.₂₅Zr₀.₂₅Hf₀.₂₅)B1.5C0.25 had respectively 94.74% and 88.56% relative density. (Ti₀.₂₅V₀.₂₅Zr₀.₂₅Hf₀.₂₅)B0.5C0.75 presented the highest relative density of 95.99%, with Vickers hardness of 26.58±1.2 GPa for the borides phase and 18.29±0.8 GPa for the carbides phase, which exceeded the reported hardness values reported in the literature for high entropy ceramics. The SPS sintered specimens containing lower boron and higher carbon presented superior properties even though the metallic composition in each phase was similar to other compositions investigated. Dual-phase high entropy (Ti₀.₂₅V₀.₂₅Zr₀.₂₅H₀.₂₅)BxCy ceramics were successfully fabricated in a boride-carbide solid solution and the amount of boron and carbon was shown to influence the phase fraction, hardness of phases, and density of the consolidated HECs. The microstructure and phase formation was highly dependent on the amount of non-metallic elements in the composition and not only the molar ratio between metals when producing high entropy ceramics with more than one anion in the sublattice. These findings show the importance of further studies about the optimization of the ratio between C and B for further improvements in the properties of dual-phase high entropy ceramics.Keywords: high-entropy ceramics, borides, carbides, dual-phase
Procedia PDF Downloads 166746 Alveolar Ridge Preservation in Post-extraction Sockets Using Concentrated Growth Factors: A Split-Mouth, Randomized, Controlled Clinical Trial
Authors: Sadam Elayah
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Background: One of the most critical competencies in advanced dentistry is alveolar ridge preservation after exodontia. The aim of this clinical trial was to assess the impact of autologous concentrated growth factor (CGF) as a socket-filling material and its ridge preservation properties following the lower third molar extraction. Materials and Methods: A total of 60 sides of 30 participants who had completely symmetrical bilateral impacted lower third molars were enrolled. The short-term outcome variables were wound healing, swelling and pain, clinically assessed at different time intervals (1st, 3rd & 7th days). While the long-term outcome variables were bone height & width, bone density and socket surface area in the coronal section. Cone beam computed tomography images were obtained immediately after surgery and three months after surgery as a temporal measure. Randomization was achieved by opaque, sealed envelopes. Follow-up data were compared to baseline using Paired & Unpaired t-tests. Results: The wound healing index was significantly better in the test sides (P =0.001). Regarding the facial swelling, the test sides had significantly fewer values than the control sides, particularly on the 1st (1.01±.57 vs 1.55 ±.56) and 3rd days (1.42±0.8 vs 2.63±1.2) postoperatively. Nonetheless, the swelling disappeared within the 7th day on both sides. The pain scores of the visual analog scale were not a statistically significant difference between both sides on the 1st day; meanwhile, the pain scores were significantly lower on the test sides compared with the control sides, especially on the 3rd (P=0.001) and 7th days (P˂0.001) postoperatively. Regarding long-term outcomes, CGF sites had higher values in height and width when compared to Control sites (Buccal wall 32.9±3.5 vs 29.4±4.3 mm, Lingual wall 25.4±3.5 vs 23.1±4 mm, and Alveolar bone width 21.07±1.55vs19.53±1.90 mm) respectively. Bone density showed significantly higher values in CGF sites than in control sites (Coronal half 200±127.3 vs -84.1±121.3, Apical half 406.5±103 vs 64.2±158.6) respectively. There was a significant difference between both sites in reducing periodontal pockets. Conclusion: CGF application following surgical extraction provides an easy, low-cost, and efficient option for alveolar ridge preservation. Thus, dentists may encourage using CGF during dental extractions, particularly when alveolar ridge preservation is required.Keywords: platelet, extraction, impacted teeth, alveolar ridge, regeneration, CGF
Procedia PDF Downloads 59745 Knowledge, Attitude and Practices of Contraception among the Married Women of Reproductive Age Group in Selected Wards of Dharan Sub-Metropolitan City
Authors: Pratima Thapa
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Background: It is very critical to understand that awareness of family planning and proper utilization of contraceptives is an important indicator for reducing maternal and neonatal mortality and morbidity. It also plays an important role in promoting reproductive health of the women in an underdeveloped country like ours. Objective: To assess knowledge, attitude and practices of contraception among married women of reproductive age group in selected wards of Dharan Sub-Metropolitan City. Materials and methods: A cross-sectional descriptive study was conducted among 209 married women of reproductive age. Simple random sampling was used to select the wards, population proportionate sampling for selecting the sample numbers from each wards and purposive sampling for selecting each sample. Semi-structured questionnaire was used to collect data. Descriptive and inferential statistics were used to interpret the data considering p-value 0.05. Results: The mean ± SD age of the respondents was 30.01 ± 8.12 years. Majority 92.3% had ever heard of contraception. Popular known method was Inj. Depo (92.7%). Mass media (85.8%) was the major source of information. Mean percentage score of knowledge was 45.23%.less than half (45%) had adequate knowledge. Majority 90.4% had positive attitude. Only 64.6% were using contraceptives currently. Misbeliefs and fear of side effects were the main reason for not using contraceptives. Education, occupation, and total income of the family was associated with knowledge regarding contraceptives. Results for Binary Logistic Regression showed significant correlates of attitude with distance to the nearest health facility (OR=7.97, p<0.01), education (OR=0.24, p<0.05) and age group (0.03, p<0.01). Regarding practice, likelihood of being current user of contraceptives increased significantly by being literate (OR=5.97, p<0.01), having nuclear family (OR=4.96, p<0.01), living in less than 30 minute walk distance from nearest health facility (OR=3.34, p<0.05), women’s participation in decision making regarding household and fertility choices (OR=5.23, p<0.01) and husband’s support on using contraceptives (OR=9.05, p<0.01). Significant and positive correlation between knowledge-attitude, knowledge-practice and attitude-practice were observed. Conclusion: Results of the study indicates that there is need to increase awareness programs in order to intensify the knowledge and practices of contraception. The positive correlation indorses that better knowledge can lead to positive attitude and hence good practice. Further, projects aiming to increase better counselling about contraceptives, its side effects and the positive effects that outweighs the negative aspects should be enrolled appropriately.Keywords: attitude, contraceptives, knowledge, practice
Procedia PDF Downloads 252744 Analysis of Autoantibodies to the S-100 Protein, NMDA, and Dopamine Receptors in Children with Type 1 Diabetes Mellitus
Authors: Yuri V. Bykov, V. A. Baturin
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Aim of the study: The aim of the study was to perform a comparative analysis of the levels of autoantibodies (AAB) to the S-100 protein as well as to the dopamine and NMDA receptors in children with type 1 diabetes mellitus (DM) in therapeutic remission. Materials and methods: Blood serum obtained from 42 children ages 4 to 17 years (20 boys and 22 girls) was analyzed. Twenty-one of these children had a diagnosis of type 1 DM and were in therapeutic remission (study group). The mean duration of disease in children with type 1 DM was 9.6±0.36 years. Children without DM were included in a group of "apparently healthy children" (21 children, comparison group). AAB to the S-100 protein, the dopamine, and NMDA receptors were measured by ELISA. The normal range of IgG AAB was specified as up to 10 µg/mL. In order to compare the central parameters of the groups, the following parametric and non-parametric methods were used: Student's t-test or Mann-Whitney U test. The level of significance for inter-group comparisons was set at p<0.05. Results: The mean levels of AAB to the S-100B protein were significantly higher (p=0.0045) in children with DM (16.84±1.54 µg/mL) when compared with "apparently healthy children" (2.09±0.05 µg/mL). The detected elevated levels of AAB to NMDA receptors may indicate that in children with type 1 DM, there is a change in the activity of the glutamatergic system, which in its turn suggests the presence of excitotoxicity. The mean levels of AAB to dopamine receptors were higher (p=0.0082) in patients comprising the study group than in the children of the comparison group (40.47±2.31 µg/mL and 3.91±0.09 µg/mL). The detected elevated levels of AAB to dopamine receptors suggest an altered activity of the dopaminergic system in children with DM. This can also be viewed as indirect evidence of altered activity of the brain's glutamatergic system. The mean levels of AAB to NMDA receptors were higher in patients with type 1 DM compared with the "apparently healthy children," at 13.16±2.07 µg/mL and 1.304±0.05 µg/mL, respectively (p=0.0021). The elevated mean levels of AAB to the S-100B protein may indicate damage to brain tissue in children with type 1 DM. A difference was also detected between the mean values of the measured AABs, and this difference depended on the duration of the disease: mean AAB values were significantly higher in patients whose disease had lasted more than five years. Conclusions: The elevated mean levels of AAB to the S-100B protein may indicate damage to brain tissue in the setting of excitotoxicity in children with type 1 DM. The discovered elevation of the levels of AAB to NMDA and dopamine receptors may indicate the activation of the glutamatergic and dopaminergic systems. The observed abnormalities indicate the presence of central nervous system damage in children with type 1 DM, with a tendency towards the elevation of the levels of the studied AABs with disease progression.Keywords: autoantibodies, brain damage, children, diabetes mellitus
Procedia PDF Downloads 84743 Medical Complications in Diabetic Recipients after Kidney Transplantation
Authors: Hakan Duger, Alparslan Ersoy, Canan Ersoy
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Diabetes mellitus is the most common etiology of end-stage renal disease (ESRD). Also, diabetic nephropathy is the etiology of ESRD in approximately 23% of kidney transplant recipients. A successful kidney transplant improves the quality of life and reduces the mortality risk for most patients. However, patients require close follow-up after transplantation due to medical complications. Diabetes mellitus can affect patient morbidity and mortality due to possible effects of immunosuppressive therapy on glucose metabolism. We compared the frequency of medical complications and the outcomes in diabetic and non-diabetic kidney transplant recipients. Materials and Methods: This retrospective study conducted in 498 patients who underwent kidney transplant surgery at our center in 10-year periods. The patients were divided into two groups: diabetics (46 ± 10 year, 26 males, 16 females) and non-diabetics (39 ± 12 year, 259 males, 197 females). The medical complications, graft functions, causes of graft loss and death were obtained from medical records. Results: There was no significant difference between recipient age, duration of dialysis, body mass index, gender, donor type, donor age, dialysis type, histories of HBV, HCV and coronary artery disease between two groups. The history of hypertension in diabetics was higher (69% vs. 36%, p < 0.001). The ratios of hypertension (50.1% vs. 57.1%), pneumonia (21.9% vs. 20%), urinary infection (16.9% vs. 20%), transaminase elevation (11.5% vs. 20%), hyperpotasemia (14.7% vs. 17.1%), hyponatremia (9.7% vs. 20%), hypotension (7.1% vs. 7.9%), hypocalcemia (1.4% vs. 0%), thrombocytopenia (8.6% vs. 8.6%), hypoglycemia (0.7% vs. 0%) and neutropenia (1.8% vs. 0%) were comparable in non-diabetic and diabetic groups, respectively. The frequency of hyperglycaemia in diabetics was higher (8.6% vs. 54.3%, p < 0.001). After transplantation, primary non-function (3.4% vs. 2.6%), delayed graft function (25.1% vs. 34.2%) and acute rejection (7.3% vs. 10.5%) ratios of in non-diabetic and diabetic groups were similar, respectively. Hospitalization durations in non-diabetics and diabetics were 22.5 ± 17.5 and 18.7 ± 13 day (p=0.094). Mean serum creatinine levels in non-diabetics and diabetics were 1.54 ± 0.74 and 1.52 ± 0.62 mg/dL at 6th month. Forty patients had graft loss. The ratios of graft loss and death in non-diabetic and diabetic groups were 8.2% vs. 7.1% and 7.1% vs. 2.6% (p > 0.05). There was no significant relationship between graft and patient survivals with the development of medical complication. Conclusion: As a result, medical complications are common in the early period. Hyperglycaemia was frequently seen following transplantation due to the effects of immunosuppressant regimens. However, the frequency of other medical complications in diabetic patients did not differ from non-diabetic one. The most important cause of death is still infections. The development of medical complications during the first 6 months did not significantly affect transplant outcomes.Keywords: kidney transplantation, diabetes mellitus, complication, graft function
Procedia PDF Downloads 324742 A Simulation-Based Investigation of the Smooth-Wall, Radial Gravity Problem of Granular Flow through a Wedge-Shaped Hopper
Authors: A. F. Momin, D. V. Khakhar
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Granular materials consist of particulate particles found in nature and various industries that, due to gravity flow, behave macroscopically like liquids. A fundamental industrial unit operation is a hopper with inclined walls or a converging channel in which material flows downward under gravity and exits the storage bin through the bottom outlet. The simplest form of the flow corresponds to a wedge-shaped, quasi-two-dimensional geometry with smooth walls and radially directed gravitational force toward the apex of the wedge. These flows were examined using the Mohr-Coulomb criterion in the classic work of Savage (1965), while Ravi Prakash and Rao used the critical state theory (1988). The smooth-wall radial gravity (SWRG) wedge-shaped hopper is simulated using the discrete element method (DEM) to test existing theories. DEM simulations involve the solution of Newton's equations, taking particle-particle interactions into account to compute stress and velocity fields for the flow in the SWRG system. Our computational results are consistent with the predictions of Savage (1965) and Ravi Prakash and Rao (1988), except for the region near the exit, where both viscous and frictional effects are present. To further comprehend this behaviour, a parametric analysis is carried out to analyze the rheology of wedge-shaped hoppers by varying the orifice diameter, wedge angle, friction coefficient, and stiffness. The conclusion is that velocity increases as the flow rate increases but decreases as the wedge angle and friction coefficient increase. We observed no substantial changes in velocity due to varying stiffness. It is anticipated that stresses at the exit result from the transfer of momentum during particle collisions; for this reason, relationships between viscosity and shear rate are shown, and all data are collapsed into a single curve. In addition, it is demonstrated that viscosity and volume fraction exhibit power law correlations with the inertial number and that all the data collapse into a single curve. A continuum model for determining granular flows is presented using empirical correlations.Keywords: discrete element method, gravity flow, smooth-wall, wedge-shaped hoppers
Procedia PDF Downloads 76741 Nanoliposomes in Photothermal Therapy: Advancements and Applications
Authors: Mehrnaz Mostafavi
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Nanoliposomes, minute lipid-based vesicles at the nano-scale, show promise in the realm of photothermal therapy (PTT). This study presents an extensive overview of nanoliposomes in PTT, exploring their distinct attributes and the significant progress in this therapeutic methodology. The research delves into the fundamental traits of nanoliposomes, emphasizing their adaptability, compatibility with biological systems, and their capacity to encapsulate diverse therapeutic substances. Specifically, it examines the integration of light-absorbing materials, like gold nanoparticles or organic dyes, into nanoliposomal formulations, enabling their efficacy as proficient agents for photothermal treatment Additionally, this paper elucidates the mechanisms involved in nanoliposome-mediated PTT, highlighting their capability to convert light energy into localized heat, facilitating the precise targeting of diseased cells or tissues. This precise regulation of light absorption and heat generation by nanoliposomes presents a non-invasive and precisely focused therapeutic approach, particularly in conditions like cancer. The study explores advancements in nanoliposomal formulations aimed at optimizing PTT outcomes. These advancements include strategies for improved stability, enhanced drug loading, and the targeted delivery of therapeutic agents to specific cells or tissues. Furthermore, the paper discusses multifunctional nanoliposomal systems, integrating imaging components or targeting elements for real-time monitoring and improved accuracy in PTT. Moreover, the review highlights recent preclinical and clinical trials showcasing the effectiveness and safety of nanoliposome-based PTT across various disease models. It also addresses challenges in clinical implementation, such as scalability, regulatory considerations, and long-term safety assessments. In conclusion, this paper underscores the substantial potential of nanoliposomes in advancing PTT as a promising therapeutic approach. Their distinctive characteristics, combined with their precise ability to convert light into heat, offer a tailored and efficient method for treating targeted diseases. The encouraging outcomes from preclinical studies pave the way for further exploration and potential clinical applications of nanoliposome-based PTT.Keywords: nanoliposomes, photothermal therapy, light absorption, heat conversion, therapeutic agents, targeted delivery, cancer therapy
Procedia PDF Downloads 85740 Selective Separation of Amino Acids by Reactive Extraction with Di-(2-Ethylhexyl) Phosphoric Acid
Authors: Alexandra C. Blaga, Dan Caşcaval, Alexandra Tucaliuc, Madalina Poştaru, Anca I. Galaction
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Amino acids are valuable chemical products used in in human foods, in animal feed additives and in the pharmaceutical field. Recently, there has been a noticeable rise of amino acids utilization throughout the world to include their use as raw materials in the production of various industrial chemicals: oil gelating agents (amino acid-based surfactants) to recover effluent oil in seas and rivers and poly(amino acids), which are attracting attention for biodegradable plastics manufacture. The amino acids can be obtained by biosynthesis or from protein hydrolysis, but their separation from the obtained mixtures can be challenging. In the last decades there has been a continuous interest in developing processes that will improve the selectivity and yield of downstream processing steps. The liquid-liquid extraction of amino acids (dissociated at any pH-value of the aqueous solutions) is possible only by using the reactive extraction technique, mainly with extractants of organophosphoric acid derivatives, high molecular weight amines and crown-ethers. The purpose of this study was to analyse the separation of nine amino acids of acidic character (l-aspartic acid, l-glutamic acid), basic character (l-histidine, l-lysine, l-arginine) and neutral character (l-glycine, l-tryptophan, l-cysteine, l-alanine) by reactive extraction with di-(2-ethylhexyl)phosphoric acid (D2EHPA) dissolved in butyl acetate. The results showed that the separation yield is controlled by the pH value of the aqueous phase: the reactive extraction of amino acids with D2EHPA is possible only if the amino acids exist in aqueous solution in their cationic forms (pH of aqueous phase below the isoeletric point). The studies for individual amino acids indicated the possibility of selectively separate different groups of amino acids with similar acidic properties as a function of aqueous solution pH-value: the maximum yields are reached for a pH domain of 2–3, then strongly decreasing with the pH increase. Thus, for acidic and neutral amino acids, the extraction becomes impossible at the isolelectric point (pHi) and for basic amino acids at a pH value lower than pHi, as a result of the carboxylic group dissociation. From the results obtained for the separation from the mixture of the nine amino acids, at different pH, it can be observed that all amino acids are extracted with different yields, for a pH domain of 1.5–3. Over this interval, the extract contains only the amino acids with neutral and basic character. For pH 5–6, only the neutral amino acids are extracted and for pH > 6 the extraction becomes impossible. Using this technique, the total separation of the following amino acids groups has been performed: neutral amino acids at pH 5–5.5, basic amino acids and l-cysteine at pH 4–4.5, l-histidine at pH 3–3.5 and acidic amino acids at pH 2–2.5.Keywords: amino acids, di-(2-ethylhexyl) phosphoric acid, reactive extraction, selective extraction
Procedia PDF Downloads 422739 Nondestructive Electrochemical Testing Method for Prestressed Concrete Structures
Authors: Tomoko Fukuyama, Osamu Senbu
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Prestressed concrete is used a lot in infrastructures such as roads or bridges. However, poor grout filling and PC steel corrosion are currently major issues of prestressed concrete structures. One of the problems with nondestructive corrosion detection of PC steel is a plastic pipe which covers PC steel. The insulative property of pipe makes a nondestructive diagnosis difficult; therefore a practical technology to detect these defects is necessary for the maintenance of infrastructures. The goal of the research is a development of an electrochemical technique which enables to detect internal defects from the surface of prestressed concrete nondestructively. Ideally, the measurements should be conducted from the surface of structural members to diagnose non-destructively. In the present experiment, a prestressed concrete member is simplified as a layered specimen to simulate a current path between an input and an output electrode on a member surface. The specimens which are layered by mortar and the prestressed concrete constitution materials (steel, polyethylene, stainless steel, or galvanized steel plates) were provided to the alternating current impedance measurement. The magnitude of an applied electric field was 0.01-volt or 1-volt, and the frequency range was from 106 Hz to 10-2 Hz. The frequency spectrums of impedance, which relate to charge reactions activated by an electric field, were measured to clarify the effects of the material configurations or the properties. In the civil engineering field, the Nyquist diagram is popular to analyze impedance and it is a good way to grasp electric relaxation using a shape of the plot. However, it is slightly not suitable to figure out an influence of a measurement frequency which is reciprocal of reaction time. Hence, Bode diagram is also applied to describe charge reactions in the present paper. From the experiment results, the alternating current impedance method looks to be applicable to the insulative material measurement and eventually prestressed concrete diagnosis. At the same time, the frequency spectrums of impedance show the difference of the material configuration. This is because the charge mobility reflects the variety of substances and also the measuring frequency of the electric field determines migration length of charges which are under the influence of the electric field. However, it could not distinguish the differences of the material thickness and is inferred the difficulties of prestressed concrete diagnosis to identify the amount of an air void or a layer of corrosion product by the technique.Keywords: capacitance, conductance, prestressed concrete, susceptance
Procedia PDF Downloads 406738 Pesticide Use Practices among Female Headed Households in the Amhara Region, Ethiopia
Authors: Birtukan Atinkut Asmare, Bernhard Freyer, Jim Bingen
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Though it is possible to transform the farming system towards a healthy, sustainable, and toxic-free food system by reducing pesticide use both in the field and postharvest, pesticides, including those that have been banned or severely restricted from use in developed countries, are indiscriminately used in African agriculture. Drawing on social practice theory, this study is about pesticide use practices in smallholder farms and its adverse impacts on women’s health and the environment, with reference to Africa, with an empirical focus on Ethiopia. Data have been collected via integrating diverse quantitative and qualitative approaches such as household surveys (n= 318), focus group discussions (n=6), field observations (n=30), and key informant interviews (n=18), with people along the pesticide value chain, including sellers and extension workers up to women farmers. A binary logistic regression model was used to investigate the factors that influence the adoption of personal protective equipment among female headed households. The findings show that Female-headed households carried out risky and unsafe practices from pesticide purchasing up to disposal, largely motivated by material elements (such as labor, income, time, and the provisioning system) but were notably shaped by competences (skills and knowledge), and meanings (norms, values, rules, and shared ideas). The main meaning or material aspect for pesticide purchasing were the perceptions of efficacy on pests, diseases, and weeds (65%), cost and availability in smaller quantities (60.7%), and a woman’s available time and mobility (58.9%). Pesticide hazards to human health or the environment seem not to be relevant for most female headed households. Unsafe practices of pesticide use among women led to the loss of biodiversity and ecosystem degradation, let alone their and family’s health. As the regression results show, the significant factors that influenced PPE adoption among female headed households were age and retailer information (p < 0.05). In line with the empirical finding, in addition to changing individual competences through advisory services and training, a foundational shift is needed in the sociocultural environment (e.g., policy, advisory), or a change in the meanings (social norms), where women are living and working.Keywords: biodiversity, competences, ecosystems, ethiopia, female headed households, materials, meanings, pesticide purchasing, pesticide using, social practice theory
Procedia PDF Downloads 65737 Effect of Enzymatic Hydrolysis and Ultrasounds Pretreatments on Biogas Production from Corn Cob
Authors: N. Pérez-Rodríguez, D. García-Bernet, A. Torrado-Agrasar, J. M. Cruz, A. B. Moldes, J. M. Domínguez
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World economy is based on non-renewable, fossil fuels such as petroleum and natural gas, which entails its rapid depletion and environmental problems. In EU countries, the objective is that at least 20% of the total energy supplies in 2020 should be derived from renewable resources. Biogas, a product of anaerobic degradation of organic substrates, represents an attractive green alternative for meeting partial energy needs. Nowadays, trend to circular economy model involves efficiently use of residues by its transformation from waste to a new resource. In this sense, characteristics of agricultural residues (that are available in plenty, renewable, as well as eco-friendly) propitiate their valorisation as substrates for biogas production. Corn cob is a by-product obtained from maize processing representing 18 % of total maize mass. Corn cob importance lies in the high production of this cereal (more than 1 x 109 tons in 2014). Due to its lignocellulosic nature, corn cob contains three main polymers: cellulose, hemicellulose and lignin. Crystalline, highly ordered structures of cellulose and lignin hinders microbial attack and subsequent biogas production. For the optimal lignocellulose utilization and to enhance gas production in anaerobic digestion, materials are usually submitted to different pretreatment technologies. In the present work, enzymatic hydrolysis, ultrasounds and combination of both technologies were assayed as pretreatments of corn cob for biogas production. Enzymatic hydrolysis pretreatment was started by adding 0.044 U of Ultraflo® L feruloyl esterase per gram of dry corncob. Hydrolyses were carried out in 50 mM sodium-phosphate buffer pH 6.0 with a solid:liquid proportion of 1:10 (w/v), at 150 rpm, 40 ºC and darkness for 3 hours. Ultrasounds pretreatment was performed subjecting corn cob, in 50 mM sodium-phosphate buffer pH 6.0 with a solid: liquid proportion of 1:10 (w/v), at a power of 750W for 1 minute. In order to observe the effect of the combination of both pretreatments, some samples were initially sonicated and then they were enzymatically hydrolysed. In terms of methane production, anaerobic digestion of the corn cob pretreated by enzymatic hydrolysis was positive achieving 290 L CH4 kg MV-1 (compared with 267 L CH4 kg MV-1 obtained with untreated corn cob). Although the use of ultrasound as the only pretreatment resulted detrimentally (since gas production decreased to 244 L CH4 kg MV-1 after 44 days of anaerobic digestion), its combination with enzymatic hydrolysis was beneficial, reaching the highest value (300.9 L CH4 kg MV-1). Consequently, the combination of both pretreatments improved biogas production from corn cob.Keywords: biogas, corn cob, enzymatic hydrolysis, ultrasound
Procedia PDF Downloads 261736 Expression of Ki-67 in Multiple Myeloma: A Clinicopathological Study
Authors: Kangana Sengar, Sanjay Deb, Ramesh Dawar
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Introduction: Ki-67 can be a useful marker in determining proliferative activity in patients with multiple myeloma (MM). However, using Ki-67 alone results in the erroneous inclusion of non-myeloma cells leading to false high counts. We have used Dual IHC (immunohistochemistry) staining with Ki-67 and CD138 to enhance specificity in assessing proliferative activity of bone marrow plasma cells. Aims and objectives: To estimate the proportion of proliferating (Ki-67 expressing) plasma cells in patients with MM and correlation of Ki-67 with other known prognostic parameters. Materials and Methods: Fifty FFPE (formalin fixed paraffin embedded) blocks of trephine biopsies of cases diagnosed as MM from 2010 to 2015 are subjected to H & E staining and Dual IHC staining for CD 138 and Ki-67. H & E staining is done to evaluate various histological parameters like percentage of plasma cells, pattern of infiltration (nodular, interstitial, mixed and diffuse), routine parameters of marrow cellularity and hematopoiesis. Clinical data is collected from patient records from Medical Record Department. Each of CD138 expressing cells (cytoplasmic, red) are scored as proliferating plasma cells (containing a brown Ki¬67 nucleus) or non¬proliferating plasma cells (containing a blue, counter-stained, Ki-¬67 negative nucleus). Ki-67 is measured as percentage positivity with a maximum score of hundred percent and lowest of zero percent. The intensity of staining is not relevant. Results: Statistically significant correlation of Ki-67 in D-S Stage (Durie & Salmon Stage) I vs. III (p=0.026) and ISS (International Staging System) Stage I vs. III (p=0.019), β2m (p=0.029) and percentage of plasma cells (p < 0.001) is seen. No statistically significant correlation is seen between Ki-67 and hemoglobin, platelet count, total leukocyte count, total protein, albumin, S. calcium, S. creatinine, S. LDH, blood urea and pattern of infiltration. Conclusion: Ki-67 index correlated with other known prognostic parameters. However, it is not determined routinely in patients with MM due to little information available regarding its relevance and paucity of studies done to correlate with other known prognostic factors in MM patients. To the best of our knowledge, this is the first study in India using Dual IHC staining for Ki-67 and CD138 in MM patients. Routine determination of Ki-67 will help to identify patients who may benefit with more aggressive therapy. Recommendation: In this study follow up of patients is not included, and the sample size is small. Studying with larger sample size and long follow up is advocated to prognosticate Ki-67 as a marker of survival in patients with multiple myeloma.Keywords: bone marrow, dual IHC, Ki-67, multiple myeloma
Procedia PDF Downloads 136735 Estimation of Morbidity Level of Industrial Labour Conditions at Zestafoni Ferroalloy Plant
Authors: M. Turmanauli, T. Todua, O. Gvaberidze, R. Javakhadze, N. Chkhaidze, N. Khatiashvili
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Background: Mining process has the significant influence on human health and quality of life. In recent years the events in Georgia were reflected on the industry working process, especially minimal requirements of labor safety, hygiene standards of workplace and the regime of work and rest are not observed. This situation is often caused by the lack of responsibility, awareness, and knowledge both of workers and employers. The control of working conditions and its protection has been worsened in many of industries. Materials and Methods: For evaluation of the current situation the prospective epidemiological study by face to face interview method was conducted at Georgian “Manganese Zestafoni Ferroalloy Plant” in 2011-2013. 65.7% of employees (1428 bulletin) were surveyed and the incidence rates of temporary disability days were studied. Results: The average length of a temporary disability single accident was studied taking into consideration as sex groups as well as the whole cohort. According to the classes of harmfulness the following results were received: Class 2.0-10.3%; 3.1-12.4%; 3.2-35.1%; 3.3-12.1%; 3.4-17.6%; 4.0-12.5%. Among the employees 47.5% and 83.1% were tobacco and alcohol consumers respectively. According to the age groups and years of work on the base of previous experience ≥50 ages and ≥21 years of work data prevalence respectively. The obtained data revealed increased morbidity rate according to age and years of work. It was found that the bone and articulate system and connective tissue diseases, aggravation of chronic respiratory diseases, ischemic heart diseases, hypertension and cerebral blood discirculation were the leading among the other diseases. High prevalence of morbidity observed in the workplace with not satisfactory labor conditions from the hygienic point of view. Conclusion: According to received data the causes of morbidity are the followings: unsafety labor conditions; incomplete of preventive medical examinations (preliminary and periodic); lack of access to appropriate health care services; derangement of gathering, recording, and analysis of morbidity data. This epidemiological study was conducted at the JSC “Manganese Ferro Alloy Plant” according to State program “ Prevention of Occupational Diseases” (Program code is 35 03 02 05).Keywords: occupational health, mining process, morbidity level, cerebral blood discirculation
Procedia PDF Downloads 420734 A Reduced Ablation Model for Laser Cutting and Laser Drilling
Authors: Torsten Hermanns, Thoufik Al Khawli, Wolfgang Schulz
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In laser cutting as well as in long pulsed laser drilling of metals, it can be demonstrated that the ablation shape (the shape of cut faces respectively the hole shape) that is formed approaches a so-called asymptotic shape such that it changes only slightly or not at all with further irradiation. These findings are already known from the ultrashort pulse (USP) ablation of dielectric and semiconducting materials. The explanation for the occurrence of an asymptotic shape in laser cutting and long pulse drilling of metals is identified, its underlying mechanism numerically implemented, tested and clearly confirmed by comparison with experimental data. In detail, there now is a model that allows the simulation of the temporal (pulse-resolved) evolution of the hole shape in laser drilling as well as the final (asymptotic) shape of the cut faces in laser cutting. This simulation especially requires much less in the way of resources, such that it can even run on common desktop PCs or laptops. Individual parameters can be adjusted using sliders – the simulation result appears in an adjacent window and changes in real time. This is made possible by an application-specific reduction of the underlying ablation model. Because this reduction dramatically decreases the complexity of calculation, it produces a result much more quickly. This means that the simulation can be carried out directly at the laser machine. Time-intensive experiments can be reduced and set-up processes can be completed much faster. The high speed of simulation also opens up a range of entirely different options, such as metamodeling. Suitable for complex applications with many parameters, metamodeling involves generating high-dimensional data sets with the parameters and several evaluation criteria for process and product quality. These sets can then be used to create individual process maps that show the dependency of individual parameter pairs. This advanced simulation makes it possible to find global and local extreme values through mathematical manipulation. Such simultaneous optimization of multiple parameters is scarcely possible by experimental means. This means that new methods in manufacturing such as self-optimization can be executed much faster. However, the software’s potential does not stop there; time-intensive calculations exist in many areas of industry. In laser welding or laser additive manufacturing, for example, the simulation of thermal induced residual stresses still uses up considerable computing capacity or is even not possible. Transferring the principle of reduced models promises substantial savings there, too.Keywords: asymptotic ablation shape, interactive process simulation, laser drilling, laser cutting, metamodeling, reduced modeling
Procedia PDF Downloads 208733 Bi-Component Particle Segregation Studies in a Spiral Concentrator Using Experimental and CFD Techniques
Authors: Prudhvinath Reddy Ankireddy, Narasimha Mangadoddy
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Spiral concentrators are commonly used in various industries, including mineral and coal processing, to efficiently separate materials based on their density and size. In these concentrators, a mixture of solid particles and fluid (usually water) is introduced as feed at the top of a spiral channel. As the mixture flows down the spiral, centrifugal and gravitational forces act on the particles, causing them to stratify based on their density and size. Spiral flows exhibit complex fluid dynamics, and interactions involve multiple phases and components in the process. Understanding the behavior of these phases within the spiral concentrator is crucial for achieving efficient separation. An experimental bi-component particle interaction study is conducted in this work utilizing magnetite (heavier density) and silica (lighter density) with different proportions processed in the spiral concentrator. The observation separation reveals that denser particles accumulate towards the inner region of the spiral trough, while a significant concentration of lighter particles are found close to the outer edge. The 5th turn of the spiral trough is partitioned into five zones to achieve a comprehensive distribution analysis of bicomponent particle segregation. Samples are then gathered from these individual streams using an in-house sample collector, and subsequent analysis is conducted to assess component segregation. Along the trough, there was a decline in the concentration of coarser particles, accompanied by an increase in the concentration of lighter particles. The segregation pattern indicates that the heavier coarse component accumulates in the inner zone, whereas the lighter fine component collects in the outer zone. The middle zone primarily consists of heavier fine particles and lighter coarse particles. The zone-wise results reveal that there is a significant fraction of segregation occurs in inner and middle zones. Finer magnetite and silica particles predominantly accumulate in outer zones with the smallest fraction of segregation. Additionally, numerical simulations are also carried out using the computational fluid dynamics (CFD) model based on the volume of fluid (VOF) approach incorporating the RSM turbulence model. The discrete phase model (DPM) is employed for particle tracking, thereby understanding the particle segregation of magnetite and silica along the spiral trough.Keywords: spiral concentrator, bi-component particle segregation, computational fluid dynamics, discrete phase model
Procedia PDF Downloads 59732 Exploring the Correlation between Body Constitution of an Individual as Per Ayurveda and Gut Microbiome in Healthy, Multi Ethnic Urban Population in Bangalore, India
Authors: Shalini TV, Gangadharan GG, Sriranjini S Jaideep, ASN Seshasayee, Awadhesh Pandit
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Introduction: Prakriti (body-mind constitution of an individual) is a conventional, customized and unique understanding of which is essential for the personalized medicine described in Ayurveda, Indian System of Medicine. Based on the Doshas( functional, bio humoral unit in the body), individuals are categorized into three major Prakriti- Vata, Pitta, and Kapha. The human gut microbiome hosts plenty of highly diverse and metabolically active microorganisms, mainly dominated by the bacteria, which are known to influence the physiology of an individual. Few researches have shown the correlation between the Prakriti and the biochemical parameters. In this study, an attempt was made to explore any correlation between the Prakriti (phenotype of an individual) with the Genetic makeup of the gut microbiome in healthy individuals. Materials and methods: 270 multi-ethnic, healthy volunteers of both sex with the age group between 18 to 40 years, with no history of antibiotics in the last 6 months were recruited into three groups of Vata, Pitta, and Kapha. The Prakriti of the individual was determined using Ayusoft, a software designed by CDAC, Pune, India. The volunteers were subjected to initial screening for the assessment of their height, weight, Body Mass Index, Vital signs and Blood investigations to ensure they are healthy. The stool and saliva samples of the recruited volunteers were collected as per the standard operating procedure developed, and the bacterial DNA was isolated using Qiagen kits. The extracted DNA was subjected to 16s rRNA sequencing using the Illumina kits. The sequencing libraries are targeting the variable V3 and V4 regions of the 16s rRNA gene. Paired sequencing was done on the MiSeq system and data were analyzed using the CLC Genomics workbench 11. Results: The 16s rRNA sequencing of the V3 and V4 regions showed a diverse pattern in both the oral and stool microbial DNA. The study did not reveal any specific pattern of bacterial flora amongst the Prakriti. All the p-values were more than the effective alpha values for all OTUs in both the buccal cavity and stool samples. Therefore, there was no observed significant enrichment of an OTU in the patient samples from either the buccal cavity or stool samples. Conclusion: In healthy volunteers of multi-ethnicity, due to the influence of the various factors, the correlation between the Prakriti and the gut microbiome was not seen.Keywords: gut microbiome, ayurveda Prakriti, sequencing, multi-ethnic urban population
Procedia PDF Downloads 125731 Enhancing Tower Crane Safety: A UAV-based Intelligent Inspection Approach
Authors: Xin Jiao, Xin Zhang, Jian Fan, Zhenwei Cai, Yiming Xu
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Tower cranes play a crucial role in the construction industry, facilitating the vertical and horizontal movement of materials and aiding in building construction, especially for high-rise structures. However, tower crane accidents can lead to severe consequences, highlighting the importance of effective safety management and inspection. This paper presents an innovative approach to tower crane inspection utilizing Unmanned Aerial Vehicles (UAVs) and an Intelligent Inspection APP System. The system leverages UAVs equipped with high-definition cameras to conduct efficient and comprehensive inspections, reducing manual labor, inspection time, and risk. By integrating advanced technologies such as Real-Time Kinematic (RTK) positioning and digital image processing, the system enables precise route planning and collection of safety hazards images. A case study conducted on a construction site demonstrates the practicality and effectiveness of the proposed method, showcasing its potential to enhance tower crane safety. On-site testing of UAV intelligent inspections reveals key findings: efficient tower crane hazard inspection within 30 minutes, with a full-identification capability coverage rates of 76.3%, 64.8%, and 76.2% for major, significant, and general hazards respectively and a preliminary-identification capability coverage rates of 18.5%, 27.2%, and 19%, respectively. Notably, UAVs effectively identify various tower crane hazards, except for those requiring auditory detection. The limitations of this study primarily involve two aspects: Firstly, during the initial inspection, manual drone piloting is required for marking tower crane points, followed by automated flight inspections and reuse based on the marked route. Secondly, images captured by the drone necessitate manual identification and review, which can be time-consuming for equipment management personnel, particularly when dealing with a large volume of images. Subsequent research efforts will focus on AI training and recognition of safety hazard images, as well as the automatic generation of inspection reports and corrective management based on recognition results. The ongoing development in this area is currently in progress, and outcomes will be released at an appropriate time.Keywords: tower crane, inspection, unmanned aerial vehicle (UAV), intelligent inspection app system, safety management
Procedia PDF Downloads 35730 Assessment of the Change in Strength Properties of Biocomposites Based on PLA and PHA after 4 Years of Storage in a Highly Cooled Condition
Authors: Karolina Mazur, Stanislaw Kuciel
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Polylactides (PLA) and polyhydroxyalkanoates (PHA) are the two groups of biodegradable and biocompatible thermoplastic polymers most commonly utilised in medicine and rehabilitation. The aim of this work is to determine the changes in the strength properties and the microstructures taking place in biodegradable polymer composites during their long-term storage in a highly cooled environment (i.e. a freezer at -24ºC) and to initially assess the durability of such biocomposites when used as single-use elements of rehabilitation or medical equipment. It is difficult to find any information relating to the feasibility of long-term storage of technical products made of PLA or PHA, but nonetheless, when using these materials to make products such as casings of hair dryers, laptops or mobile phones, it is safe to assume that without storing in optimal conditions their degradation time might last even several years. SEM images and the assessment of the strength properties (tensile, bending and impact testing) were carried out and the density and water sorption of two polymers, PLA and PHA (NaturePlast PLE 001 and PHE 001), filled with cellulose fibres (corncob grain – Rehofix MK100, Rettenmaier&Sohne) up to 10 and 20% mass were determined. The biocomposites had been stored at a temperature of -24ºC for 4 years. In order to find out the changes in the strength properties and the microstructure taking place after such a long time of storage, the results of the assessment have been compared with the results of the same research carried out 4 years before. Results shows a significant change in the manner of fractures – from ductile with developed surface for the PHA composite with corncob grain when the tensile testing was performed directly after the injection into a more brittle state after 4 years of storage, which is confirmed by the strength tests, where a decrease of deformation is observed at point of fracture. The research showed that there is a way of storing medical devices made out of PLA or PHA for a reasonably long time, as long as the required temperature of storage is met. The decrease of mechanical properties found during tensile testing and bending for PLA was less than 10% of the tensile strength, while the modulus of elasticity and deformation at fracturing slightly rose, which may implicate the beginning of degradation processes. The strength properties of PHA are even higher after 4 years of storage, although in that case the decrease of deformation at fracturing is significant, reaching even 40%, which suggests its degradation rate is higher than that of PLA. The addition of natural particles in both cases only slightly increases the biodegradation.Keywords: biocomposites, PLA, PHA, storage
Procedia PDF Downloads 259729 The Microstructural and Mechanical Characterization of Organo-Clay-Modified Bitumen, Calcareous Aggregate, and Organo-Clay Blends
Authors: A. Gürses, T. B. Barın, Ç. Doğar
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Bitumen has been widely used as the binder of aggregate in road pavement due to its good viscoelastic properties, as a viscous organic mixture with various chemical compositions. Bitumen is a liquid at high temperature and it becomes brittle at low temperatures, and this temperature-sensitivity can cause the rutting and cracking of the pavement and limit its application. Therefore, the properties of existing asphalt materials need to be enhanced. The pavement with polymer modified bitumen exhibits greater resistance to rutting and thermal cracking, decreased fatigue damage, as well as stripping and temperature susceptibility; however, they are expensive and their applications have disadvantages. Bituminous mixtures are composed of very irregular aggregates bound together with hydrocarbon-based asphalt, with a low volume fraction of voids dispersed within the matrix. Montmorillonite (MMT) is a layered silicate with low cost and abundance, which consists of layers of tetrahedral silicate and octahedral hydroxide sheets. Recently, the layered silicates have been widely used for the modification of polymers, as well as in many different fields. However, there are not too much studies related with the preparation of the modified asphalt with MMT, currently. In this study, organo-clay-modified bitumen, and calcareous aggregate and organo-clay blends were prepared by hot blending method with OMMT, which has been synthesized using a cationic surfactant (Cetyltrymethylammonium bromide, CTAB) and long chain hydrocarbon, and MMT. When the exchangeable cations in the interlayer region of pristine MMT were exchanged with hydrocarbon attached surfactant ions, the MMT becomes organophilic and more compatible with bitumen. The effects of the super hydrophobic OMMT onto the micro structural and mechanic properties (Marshall Stability and volumetric parameters) of the prepared blends were investigated. Stability and volumetric parameters of the blends prepared were measured using Marshall Test. Also, in order to investigate the morphological and micro structural properties of the organo-clay-modified bitumen and calcareous aggregate and organo-clay blends, their SEM and HRTEM images were taken. It was observed that the stability and volumetric parameters of the prepared mixtures improved significantly compared to the conventional hot mixes and even the stone matrix mixture. A micro structural analysis based on SEM images indicates that the organo-clay platelets dispersed in the bitumen have a dominant role in the increase of effectiveness of bitumen - aggregate interactions.Keywords: hot mix asphalt, stone matrix asphalt, organo clay, Marshall test, calcareous aggregate, modified bitumen
Procedia PDF Downloads 233728 The Characterization and Optimization of Bio-Graphene Derived From Oil Palm Shell Through Slow Pyrolysis Environment and Its Electrical Conductivity and Capacitance Performance as Electrodes Materials in Fast Charging Supercapacitor Application
Authors: Nurhafizah Md. Disa, Nurhayati Binti Abdullah, Muhammad Rabie Bin Omar
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This research intends to identify the existing knowledge gap because of the lack of substantial studies to fabricate and characterize bio-graphene created from Oil Palm Shell (OPS) through the means of pre-treatment and slow pyrolysis. By fabricating bio-graphene through OPS, a novel material can be found to procure and used for graphene-based research. The characterization of produced bio-graphene is intended to possess a unique hexagonal graphene pattern and graphene properties in comparison to other previously fabricated graphene. The OPS will be fabricated by pre-treatment of zinc chloride (ZnCl₂) and iron (III) chloride (FeCl3), which then induced the bio-graphene thermally by slow pyrolysis. The pyrolizer's final temperature and resident time will be set at 550 °C, 5/min, and 1 hour respectively. Finally, the charred product will be washed with hydrochloric acid (HCL) to remove metal residue. The obtained bio-graphene will undergo different analyses to investigate the physicochemical properties of the two-dimensional layer of carbon atoms with sp2 hybridization hexagonal lattice structure. The analysis that will be taking place is Raman Spectroscopy (RAMAN), UV-visible spectroscopy (UV-VIS), Transmission Electron Microscopy (TEM), Scanning Electron Microscopy (SEM), and X-Ray Diffraction (XRD). In retrospect, RAMAN is used to analyze three key peaks found in graphene, namely D, G, and 2D peaks, which will evaluate the quality of the bio-graphene structure and the number of layers generated. To compare and strengthen graphene layer resolves, UV-VIS may be used to establish similar results of graphene layer from last layer analysis and also characterize the types of graphene procured. A clear physical image of graphene can be obtained by analyzation of TEM in order to study structural quality and layers condition and SEM in order to study the surface quality and repeating porosity pattern. Lastly, establishing the crystallinity of the produced bio-graphene, simultaneously as an oxygen contamination factor and thus pristineness of the graphene can be done by XRD. In the conclusion of this paper, this study is able to obtain bio-graphene through OPS as a novel material in pre-treatment by chloride ZnCl₂ and FeCl3 and slow pyrolization to provide a characterization analysis related to bio-graphene that will be beneficial for future graphene-related applications. The characterization should yield similar findings to previous papers as to confirm graphene quality.Keywords: oil palm shell, bio-graphene, pre-treatment, slow pyrolysis
Procedia PDF Downloads 76727 Growth Stimulating Effects of Aspilia africana Fed to Female Pseudo-Ruminant Herbivores (Rabbits) at Different Physiological States
Authors: Nseabasi Nsikakabasi Etim
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In recent times, there has been a significant shortfall in between the production and supply of animal protein to meet the ever increasing population. To meet the increasing demand for animal protein, there is a need to focus attention on the production of livestock whose nutritional requirement does not put much strain on the limited sources of feed ingredients to which men subscribe. An example of such livestock is the rabbit. Rabbit is a pseudo-ruminant herbivore which utilizes much undigested and unabsorbed feed materials as sources of nutrient for maintenance and production. Thus, this study was conducted to investigate the effects of feeding Aspilia africana as forage on the growth rates of female pseudo-ruminant herbivores (rabbits) at different physiological states. Thirty (30) Dutch breed rabbit does of 5–6 months of age were used for the experiment which was conducted in a completely randomized design for four months. The rabbits were divided into three treatment groups, ten does per treatment group; which consisted of mixed forages (Centrosema pubescent (200g), Panicum maximum (200g) and Ipomea batatas leaves (100g) without Aspilia africana (T1; control), fresh Aspilia africana (500g/dose/day) (T2) and wilted Aspilia africana (500g/dose/day) (T3). Rabbits in all treatment groups received the same concentrate (300g/animal/day) throughout the period of the study and mixed forages from the commencement of the experiment till the does kindled. After parturition, fresh and wilted Aspilia africana were introduced in treatments 2 and three respectively, whereas the control group continued on mixed forages throughout the study. The result of the study revealed that the initial average body weight of the rabbit does was 1.74kg. At mating and gestation periods, the body weights of the does in T2 was significantly higher (P<0.05) than the rest. There were no significant differences (P<0.05) in the body weights of does at kindling between the various treatment groups. During the physiological states of lactation, weaning and re-mating, the control group (T1) had significantly lower body weight than those of the treated groups (T2 and T3). Furthermore, T2 had significantly higher body weight than T3. The study revealed that Aspilia africana; mainly the fresh leaves have greater growth stimulating effects when fed to pseudo-ruminants (rabbits), thereby enhancing body weights of does during lactation and weaning.Keywords: Aspilia africana, herbivores, pseudo-ruminants, physiological states
Procedia PDF Downloads 680726 Determination of Identification and Antibiotic Resistance Rates of Serratia marcescens and Providencia Spp. from Various Clinical Specimens by Using Both the Conventional and Automated (VITEK2) Methods
Authors: Recep Keşli, Gülşah Aşık, Cengiz Demir, Onur Türkyılmaz
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Objective: Serratia species are identified as aerobic, motile Gram negative rods. The species Serratia marcescens (S. marcescens) causes both opportunistic and nosocomial infections. The genus Providencia is Gram-negative bacilli and includes urease-producing that is responsible for a wide range of human infections. Although most Providencia infections involve the urinary tract, they are also associated with gastroenteritis, wound infections, and bacteremia. The aim of this study was evaluate the antimicrobial resistance rates of S. marcescens and Providencia spp. strains which had been isolated from various clinical materials obtained from different patients who belongs to intensive care units (ICU) and inpatient clinics. Methods: A total of 35 S. marcescens and Providencia spp. strains isolated from various clinical samples admitted to Medical Microbiology Laboratory, ANS Research and Practice Hospital, Afyon Kocatepe University between October 2013 and September 2015 were included in the study. Identification of the bacteria was determined by conventional methods and VITEK 2 system (bio-Merieux, Marcy l’etoile, France) was used additionally. Antibacterial resistance tests were performed by using Kirby Bauer disc (Oxoid, Hampshire, England) diffusion method following the recommendations of CLSI. Results: The distribution of clinical samples were as follows: upper and lower respiratory tract samples 26, 74.2 % wound specimen 6, 17.1 % blood cultures 3, 8.5%. Of the 35 S. marcescens and Providencia spp. strains; 28, 80% were isolated from clinical samples sent from ICU. The resistance rates of S. marcescens strains against trimethoprim-sulfamethoxazole, piperacillin-tazobactam, imipenem, gentamicin, ciprofloxacin, ceftazidime, cefepime and amikacin were found to be 8.5 %, 22.8 %, 11.4 %, 2.8 %, 17.1 %, 40 %, 28.5 % and 5.7 % respectively. Resistance rates of Providencia spp. strains against trimethoprim-sulfamethoxazole, piperacillin-tazobactam, imipenem, gentamicin, ciprofloxacin, ceftazidime, cefepime and amikacin were found to be 10.2 %, 33,3 %, 18.7 %, 8.7 %, 13.2 %, 38.6 %, 26.7%, and 11.8 % respectively. Conclusion: S. marcescens is usually resistant to ampicillin, amoxicillin, amoxicillin/clavulanate, ampicillin/sulbactam, cefuroxime, cephamycins, nitrofurantoin, and colistin. The most effective antibiotic on the total of S. marcescens strains was found to be gentamicin 2.8 %, of the totally tested strains the highest resistance rate found against to ceftazidime 40 %. The lowest and highest resistance rates were found against gentamiycin and ceftazidime with the rates of 8.7 % and 38.6 % for Providencia spp.Keywords: Serratia marcescens, Providencia spp., antibiotic resistance, intensive care unit
Procedia PDF Downloads 238725 Ethiopia as a Tourist Destination: An Exploration of Italian Tourists’ Market Demand
Authors: Frezer Okubay Weldegebriel
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The tourism sector in Ethiopia plays a significant role in the national economy. The government is granting its pledge and readiness to develop this sector through various initiatives since to eradicate poverty and encourage economic development of the country is one of the Millennium Development plans. The tourism sector has been identified as one of the priority economic sectors by many countries, and the Government of Ethiopia has planned to make Ethiopia among the top five African destinations by 2020. Nevertheless, the international tourism demand for Ethiopia currently lags behind other African countries such as South Africa, Egypt, Morocco, Tanzania, and Kenya. Meanwhile, the number of international tourists’ arrival in Ethiopia is recently increasing even if it cannot be competitive with other African countries. Therefore, to offer demand-driven tourism products, the Ethiopian government, Tourism planners, Tour & Travel operators need to understand the important factors, which affect international tourists’ decision to visit Ethiopian destinations. This study was intended to analyze Italian Tourists Demand towards Ethiopian destination. The researcher aimed to identify the demand for Italian tourists’ preference to Ethiopian destinations comparing to the top East African countries. This study uses both qualitative and quantitative research methodology, and the data is manipulating through primary data collection method using questionnaires, interviews, and secondary data by reviewing books, journals, magazines, past researches, and websites. An active and potential Italian tourist cohort, five well-functioning tour operators based in Ethiopia for Italian tourists and professionals from Ethiopian Ministry of Tourism and Culture participated. Based on the analysis of the data collected through the questionnaire, interviews, and reviews of different materials, the study disclosed that the majority of Italian tourists have a high demand on Ethiopian Tourist destination. Historical and cultural interest, safety and security, the hospitality of the people and affordable accommodation coast are the main reason for them. However, some Italian tourists prefer to visit Kenya, Tanzania, and Uganda due to the fact that they are fascinated by adventure, safari and beaches, while Ethiopia cannot provide these attractions. Most Italian tourists have little information and practical experiences on Ethiopian tourism possibilities via a tour and travel companies. Moreover, the insufficient marketing campaign and promotion by Ethiopian Government and Ministry of Tourism could also contribute to the failure of Ethiopian tourism.Keywords: The demand of Italian tourists, Ethiopia economy, Ethiopia tourism destination, promoting Ethiopia tourism
Procedia PDF Downloads 192724 Change of Bone Density with Treatments of Intravenous Zoledronic Acid in Patients with Osteoporotic Distal Radial Fractures
Authors: Hong Je Kang, Young Chae Choi, Jin Sung Park, Isac Kim
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Purpose: Osteoporotic fractures are an important among postmenopausal women. When osteoporotic distal radial fractures occur, osteoporosis must be treated to prevent the hip and spine fractures. Intravenous injection of Zoledronic acid is expected to improve preventing osteoporotic fractures. Many articles reported the effect of intravenous Zoledronic acid to BMD of the hip and spine fracture or non-fracture patients with low BMD. However, that with distal radial fractures has rarely been reported. Therefore, the authors decided to study the effect of Zoledronic acid in BMD score, bone union, and bone turnover markers in the patients who underwent volar plating due to osteoporotic distal radial fractures. Materials: From April 2018 to May 2022, postmenopausal women aged 55 years or older who had osteoporotic distal radial fractures and who underwent surgical treatment using volar plate fixation were included. Zoledronic acid (5mg) was injected intravenously between 3 and 5 days after surgery. BMD scores after 1 year of operation were compared with the initial scores. Bone turnover markers were measured before surgery, after 3 months, and after 1 year. Radiological follow-up was performed every 2 weeks until the bone union and at 1 year postoperatively. Clinical outcome indicators were measured one year after surgery, and the occurrence of side effects was observed. Result: Total of 23 patients were included, with a lumbar BMD T score of -2.89±0.2 before surgery to -2.27±0.3 one year after surgery (p=0.012) and a femoral neck BMD T score of -2.45±0.3 before surgery to -2.36±0.3 (p=0.041) after one year, and all were statistically significant. Measured as bone resorption markers, serum CTX-1 was 337.43±10.4 pg/mL before surgery, 160.86±8.7 pg/mL (p=0.022) after three months, and 250.12±12.7 pg/mL (p=0.031) after one year. Urinary NTX-1 was 39.24±2.2 ng/mL before surgery, 24.46±1.2 ng/mL (p=0.014) after three months and 30.35±1.6 ng/mL (p=0.042) after one year. Measured as bone formation markers, serum osteocalcin was 13.04±1.1 ng/mL before surgery, 8.84±0.7 ng/mL (p=0.037) after 3 months and 11.1±0.4 ng/mL (p=0.026) after one year. Serum bone-specific ALP was 11.24±0.9 IU/L before surgery, 8.25±0.9 IU/L (p=0.036) after three months, and 10.2±0.9 IU/L (p=0.027) after one year. All were statistically significant. All cases showed bone union within an average of 6.91±0.3 weeks without any signs of failure. Complications were found in 5 out of 23 cases (21.7%), such as headache, nausea, muscle pain, and fever. Conclusion: When Zoledronic acid was used, BMD was improved in both the spine and femoral neck. This may reduce the likelihood and subsequent morbidity of additional osteoporotic fractures. This study is meaningful in that there was no difference in the duration of bone union and radiological characteristics in patients with distal radial fractures administrated with intravenous BP early after the fractures, and improvement in BMD and bone turnover indicators was measured.Keywords: zeoldreonic acid, BMD, osteoporosis, distal radius
Procedia PDF Downloads 107723 Dependence of Androgen Status in Men with Primary Hypothyroidism on Duration and Condition of Compensation
Authors: Krytskyy T.
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Introduction: The role of androgen deficiency in men as a factor in the pathogenesis of many somatic diseases is unmistakable. The interaction of thyroid and sex hormones with hypothyroidism in men is still the subject of discussions. The purpose of the study is to assess the androgen status of men with primary hypothyroidism, depending on its duration and the state of compensation. Materials and methods: 45 men with primary hypothyroidism aged 35 to 60 years, as well as 25 healthy men, who formed a control group, were under supervision. A selection of men for examination was conducted in the process of outpatient and in-patient treatment at the endocrinology department of the University Hospital in Ternopil. The functional state of the pituitary-gonadal system was evaluated in order to characterize the androgen status of patients. The concentration of follicle stimulating hormone, luteinizing hormone, prolactin, thyroid-stimulating hormone was determined in blood with the help of enzyme-linked method. Also, the content of hormones: total testosterone, linking sex hormones globulin were determined. Results: Reduced total testosterone (TT) content was found in 42.2% of patients with hypothyroidism. Herewith in 17.8% of patients, blood TT levels were lower than 8.0 nmol / L, and in 11 (24.4%) men, the rate was in the range of 8.0 to 12.0 nmol / L. Based on the results of the determination of the content of free testosterone (FT), the frequency of laboratory hypogonadism in men with hypothyroidism was higher than the results of the determination of TT. The degree of compensation of hypothyroidism probably did not affect the average levels of gonadotropic and sex hormones. Conclusions: Reduced total testosterone content was found in 42.2% of patients with primary hypothyroidism. Herewith, in 17.8% of patients blood TT levels were lower than 8.0 nmol / L, which is a sign of absolute deficiency of testosterone, and in 24.4% of men the rate ranged from 8.0 to 12.0 nmol / l , indicating partial androgen deficiency. Linking sex hormones globulin levels were believed to be lower in 46.7% of patients with hypothyroidism compared to control group. The average levels of E2 in the examined patients did not significantly differ from the mean of control group. FSH, LH, and prolactin levels in men with hypothyroidism were within the normal age limits and probably did not differ from those of control group. The degree of compensation of hypothyroidism probably did not affect the average levels of gonadotropic and sex hormones. The mean LH content in the blood was significantly increased in men with a duration of hypothyroidism up to 5 years and did not differ from that of the control group and in men with a duration of hypothyroidism over 5 years. In men with hypothyroidism, a probable reduction in T / LH coefficient is found. The obtained data may indicate a combined lesion of the central and peripheral parts of the pituitary-gonadal system in men with hypothyroidism.Keywords: androgenic status, hypothyroidism, testosterone, linking sex hormones globulin
Procedia PDF Downloads 177722 Implementation of Correlation-Based Data Analysis as a Preliminary Stage for the Prediction of Geometric Dimensions Using Machine Learning in the Forming of Car Seat Rails
Authors: Housein Deli, Loui Al-Shrouf, Hammoud Al Joumaa, Mohieddine Jelali
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When forming metallic materials, fluctuations in material properties, process conditions, and wear lead to deviations in the component geometry. Several hundred features sometimes need to be measured, especially in the case of functional and safety-relevant components. These can only be measured offline due to the large number of features and the accuracy requirements. The risk of producing components outside the tolerances is minimized but not eliminated by the statistical evaluation of process capability and control measurements. The inspection intervals are based on the acceptable risk and are at the expense of productivity but remain reactive and, in some cases, considerably delayed. Due to the considerable progress made in the field of condition monitoring and measurement technology, permanently installed sensor systems in combination with machine learning and artificial intelligence, in particular, offer the potential to independently derive forecasts for component geometry and thus eliminate the risk of defective products - actively and preventively. The reliability of forecasts depends on the quality, completeness, and timeliness of the data. Measuring all geometric characteristics is neither sensible nor technically possible. This paper, therefore, uses the example of car seat rail production to discuss the necessary first step of feature selection and reduction by correlation analysis, as otherwise, it would not be possible to forecast components in real-time and inline. Four different car seat rails with an average of 130 features were selected and measured using a coordinate measuring machine (CMM). The run of such measuring programs alone takes up to 20 minutes. In practice, this results in the risk of faulty production of at least 2000 components that have to be sorted or scrapped if the measurement results are negative. Over a period of 2 months, all measurement data (> 200 measurements/ variant) was collected and evaluated using correlation analysis. As part of this study, the number of characteristics to be measured for all 6 car seat rail variants was reduced by over 80%. Specifically, direct correlations for almost 100 characteristics were proven for an average of 125 characteristics for 4 different products. A further 10 features correlate via indirect relationships so that the number of features required for a prediction could be reduced to less than 20. A correlation factor >0.8 was assumed for all correlations.Keywords: long-term SHM, condition monitoring, machine learning, correlation analysis, component prediction, wear prediction, regressions analysis
Procedia PDF Downloads 26721 A Mixed Finite Element Formulation for Functionally Graded Micro-Beam Resting on Two-Parameter Elastic Foundation
Authors: Cagri Mollamahmutoglu, Aykut Levent, Ali Mercan
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Micro-beams are one of the most common components of Nano-Electromechanical Systems (NEMS) and Micro Electromechanical Systems (MEMS). For this reason, static bending, buckling, and free vibration analysis of micro-beams have been the subject of many studies. In addition, micro-beams restrained with elastic type foundations have been of particular interest. In the analysis of microstructures, closed-form solutions are proposed when available, but most of the time solutions are based on numerical methods due to the complex nature of the resulting differential equations. Thus, a robust and efficient solution method has great importance. In this study, a mixed finite element formulation is obtained for a functionally graded Timoshenko micro-beam resting on two-parameter elastic foundation. In the formulation modified couple stress theory is utilized for the micro-scale effects. The equation of motion and boundary conditions are derived according to Hamilton’s principle. A functional, derived through a scientific procedure based on Gateaux Differential, is proposed for the bending and buckling analysis which is equivalent to the governing equations and boundary conditions. Most important advantage of the formulation is that the mixed finite element formulation allows usage of C₀ type continuous shape functions. Thus shear-locking is avoided in a built-in manner. Also, element matrices are sparsely populated and can be easily calculated with closed-form integration. In this framework results concerning the effects of micro-scale length parameter, power-law parameter, aspect ratio and coefficients of partially or fully continuous elastic foundation over the static bending, buckling, and free vibration response of FG-micro-beam under various boundary conditions are presented and compared with existing literature. Performance characteristics of the presented formulation were evaluated concerning other numerical methods such as generalized differential quadrature method (GDQM). It is found that with less computational burden similar convergence characteristics were obtained. Moreover, formulation also includes a direct calculation of the micro-scale related contributions to the structural response as well.Keywords: micro-beam, functionally graded materials, two-paramater elastic foundation, mixed finite element method
Procedia PDF Downloads 147720 The Staphylococcus aureus Exotoxin Recognition Using Nanobiosensor Designed by an Antibody-Attached Nanosilica Method
Authors: Hamed Ahari, Behrouz Akbari Adreghani, Vadood Razavilar, Amirali Anvar, Sima Moradi, Hourieh Shalchi
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Considering the ever increasing population and industrialization of the developmental trend of humankind's life, we are no longer able to detect the toxins produced in food products using the traditional techniques. This is due to the fact that the isolation time for food products is not cost-effective and even in most of the cases, the precision in the practical techniques like the bacterial cultivation and other techniques suffer from operator errors or the errors of the mixtures used. Hence with the advent of nanotechnology, the design of selective and smart sensors is one of the greatest industrial revelations of the quality control of food products that in few minutes time, and with a very high precision can identify the volume and toxicity of the bacteria. Methods and Materials: In this technique, based on the bacterial antibody connection to nanoparticle, a sensor was used. In this part of the research, as the basis for absorption for the recognition of bacterial toxin, medium sized silica nanoparticles of 10 nanometer in form of solid powder were utilized with Notrino brand. Then the suspension produced from agent-linked nanosilica which was connected to bacterial antibody was positioned near the samples of distilled water, which were contaminated with Staphylococcus aureus bacterial toxin with the density of 10-3, so that in case any toxin exists in the sample, a connection between toxin antigen and antibody would be formed. Finally, the light absorption related to the connection of antigen to the particle attached antibody was measured using spectrophotometry. The gene of 23S rRNA that is conserved in all Staphylococcus spp., also used as control. The accuracy of the test was monitored by using serial dilution (l0-6) of overnight cell culture of Staphylococcus spp., bacteria (OD600: 0.02 = 107 cell). It showed that the sensitivity of PCR is 10 bacteria per ml of cells within few hours. Result: The results indicate that the sensor detects up to 10-4 density. Additionally, the sensitivity of the sensors was examined after 60 days, the sensor by the 56 days had confirmatory results and started to decrease after those time periods. Conclusions: Comparing practical nano biosensory to conventional methods like that culture and biotechnology methods(such as polymerase chain reaction) is accuracy, sensitiveness and being unique. In the other way, they reduce the time from the hours to the 30 minutes.Keywords: exotoxin, nanobiosensor, recognition, Staphylococcus aureus
Procedia PDF Downloads 379719 Engineering Topology of Ecological Model for Orientation Impact of Sustainability Urban Environments: The Spatial-Economic Modeling
Authors: Moustafa Osman Mohammed
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The modeling of a spatial-economic database is crucial in recitation economic network structure to social development. Sustainability within the spatial-economic model gives attention to green businesses to comply with Earth’s Systems. The natural exchange patterns of ecosystems have consistent and periodic cycles to preserve energy and materials flow in systems ecology. When network topology influences formal and informal communication to function in systems ecology, ecosystems are postulated to valence the basic level of spatial sustainable outcome (i.e., project compatibility success). These referred instrumentalities impact various aspects of the second level of spatial sustainable outcomes (i.e., participant social security satisfaction). The sustainability outcomes are modeling composite structure based on a network analysis model to calculate the prosperity of panel databases for efficiency value, from 2005 to 2025. The database is modeling spatial structure to represent state-of-the-art value-orientation impact and corresponding complexity of sustainability issues (e.g., build a consistent database necessary to approach spatial structure; construct the spatial-economic-ecological model; develop a set of sustainability indicators associated with the model; allow quantification of social, economic and environmental impact; use the value-orientation as a set of important sustainability policy measures), and demonstrate spatial structure reliability. The structure of spatial-ecological model is established for management schemes from the perspective pollutants of multiple sources through the input–output criteria. These criteria evaluate the spillover effect to conduct Monte Carlo simulations and sensitivity analysis in a unique spatial structure. The balance within “equilibrium patterns,” such as collective biosphere features, has a composite index of many distributed feedback flows. The following have a dynamic structure related to physical and chemical properties for gradual prolong to incremental patterns. While these spatial structures argue from ecological modeling of resource savings, static loads are not decisive from an artistic/architectural perspective. The model attempts to unify analytic and analogical spatial structure for the development of urban environments in a relational database setting, using optimization software to integrate spatial structure where the process is based on the engineering topology of systems ecology.Keywords: ecological modeling, spatial structure, orientation impact, composite index, industrial ecology
Procedia PDF Downloads 52718 Refractory Cardiac Arrest: Do We Go beyond, Do We Increase the Organ Donation Pool or Both?
Authors: Ortega Ivan, De La Plaza Edurne
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Background: Spain and other European countries have implemented Uncontrolled Donation after Cardiac Death (uDCD) programs. After 15 years of experience in Spain, many things have changed. Recent evidence and technical breakthroughs achieved in resuscitation are relevant for uDCD programs and raise some ethical concerns related to these protocols. Aim: To rethink current uDCD programs in the light of recent evidence on available therapeutic procedures applicable to victims of out-of-hospital cardiac arrest (OHCA). To address the following question: What is the current standard of treatment owed to victims of OHCA before including them in an uDCD protocol? Materials and Methods: Review of the scientific and ethical literature related to both uDCD programs and innovative resuscitation techniques. Results: 1) The standard of treatment received and the chances of survival of victims of OHCA depend on whether they are classified as Non-Heart Beating Patients (NHBP) or Non-Heart-Beating-Donors (NHBD). 2) Recent studies suggest that NHBPs are likely to survive, with good quality of life, if one or more of the following interventions are performed while ongoing CPR -guided by suspected or known cause of OHCA- is maintained: a) direct access to a Cath Lab-H24 or/and to extra-corporeal life support (ECLS); b) transfer in induced hypothermia from the Emergency Medical Service (EMS) to the ICU; c) thrombolysis treatment; d) mobile extra-corporeal membrane oxygenation (mini ECMO) instituted as a bridge to ICU ECLS devices. 3) Victims of OHCA who cannot benefit from any of these therapies should be considered as NHBDs. Conclusion: Current uDCD protocols do not take into account recent improvements in resuscitation and need to be adapted. Operational criteria to distinguish NHBDs from NHBP should seek a balance between the technical imperative (to do whatever is possible), considerations about expected survival with quality of life, and distributive justice (costs/benefits). Uncontrolled DCD protocols can be performed in a way that does not hamper the legitimate interests of patients, potential organ donors, their families, the organ recipients, and the health professionals involved in these processes. Families of NHBDs’ should receive information which conforms to the ethical principles of respect of autonomy and transparency.Keywords: uncontrolled donation after cardiac death resuscitation, refractory cardiac arrest, out of hospital cardiac, arrest ethics
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