Search results for: burn wounds

Authors: S. S. Pathak, M. A. Borkar, S. S. Patel

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To compare Healing Effects of an Ayurvedic Preparation and Silver Sulfadiazine on burn wounds in Albino Rats. Methods: Albino rats– 30 male / female rats weighing between 150-200 g were used in the study. They were individually housed and maintained on normal diet and water ad libitum. Partial thickness burn wounds were inflicted, on overnight-starved animals under pentobarbitone (30mg/kg, i.p.) anaesthesia, by pouring hot molten wax at 80oC into a plastic cylinder of 300 mm2 circular openings placed on the shaven back of the animal. Apart from the drugs under investigation no local/ systemic chemotherapeutic cover will be provided to animals. All the animals were assessed for the percentage of wound contraction, signs of infection, scab formation and histopathological examination. Results: Percentage of wound healing was significantly better in the test ointment group compared to the standard. Signs of infection were observed in more animals in the test ointment group compared to the standard. Scab formation also took place earlier in the test ointment group compared to standard. Epithelial regeneration and healing profile was better in the test ointment compared to the standard. Moreover the test ointment group did not show any raised margins in the wound or blackish discoloration as was observed in silver sulfadiazine group. Conclusion: The burn wound healing effect of the ayurvedic ointment under study is better in comparison to standard therapy of silver sulfadiazine. The problem of infection encountered with the test ointment can be overcome by changing the concentrations and proportions of the ingredients in the test ointment which constitutes the further plan of the study.

Keywords: Ayurvedic test ointment, burn wounds, Silver sulfadiazine.

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Authors: M.A. Calin, D. Voicu, M.R. Calin, D. Savastru, D. Manea

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In this paper we evaluated the efficacy of photodynamic treatment of infected wounds on pig animal model by diffuse reflectance spectrometry. The study was conducted on fifteen wounds contaminated with Staphylococcus aureus bacteria that were incubated for 30 min with methylene blue solution (c = 3.3 x 10-3 M) and exposed to laser radiations (λ = 670 nm, P = 15 mW) for 15 min. The efficiency of photodynamic inactivation of bacteria was evaluated by microbiological exams and diffuse reflectance spectrometry. The results of the microbiological exams showed that the bacterial concentration has decreased from 6.93±0.138 logCFU/ml to 3.12±0.108 logCFU/ml. The spectral examination showed that the diffuse reflectance of wounds contaminated with Staphylococcus aureus has decreased from 5.06±0.036 % to 3.36±0.025 %. In conclusion, photodynamic therapy is an effective method for the treatment of infected wounds and there is a correlation between the CFU count and diffuse reflectance.

Keywords: photodynamic inactivation, bacteria, pigs, wounds

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Authors: J. O. Akinyele, R. W. Salim, K. O. Oikelome, O. T. Olateju

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Rice Husk (RH) is the major byproduct in the processing of paddy rice. The management of this waste has become a big challenge to some of the rice producers, some of these wastes are left in open dumps while some are burn in the open space, and these two actions have been contributing to environmental pollution. This study evaluates an alternative waste management of this agricultural product for use as a civil engineering material. The RH was burn in a controlled environment to form Rice Husk Ash (RHA). The RHA was mix with lateritic clay at 0, 2, 4, 6, 8, and 10% proportion by weight. Chemical test was conducted on the open burn and controlled burn RHA with the lateritic clay. Physical test such as particle size distribution, Atterberg limits test, and density test were carried out on the mix material. The chemical composition obtained for the RHA showed that the total percentage compositions of Fe2O3, SiO2 and Al2O3 were found to be above 70% (class “F” pozzolan) which qualifies it as a very good pozzolan. The coefficient of uniformity (Cu) was 8 and coefficient of curvature (Cc) was 2 for the soil sample. The Plasticity Index (PI) for the 0, 2, 4, 6, 8. 10% was 21.0, 18.8, 16.7, 14.4, 12.4 and 10.7 respectively. The work concluded that RHA can be effectively used in hydraulic barriers and as a stabilizing agent in soil stabilization.

Keywords: Rice husk ash, pozzolans, paddy rice, lateritic clay.

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Authors: S. Moustafa El Shanawany, I. Labib Salem, F. Mohamed Magdy Badr El Dine, H. Tag El Deen Abd Allah

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Thermal injuries remain a global health problem and a common issue encountered in forensic pathology. They are a devastating cause of morbidity and mortality in children and adults especially in developing countries, causing permanent disfigurement, scarring and grievous hurt. Burns have always been a matter of legal concern in cases of suicidal burns, self-inflicted burns for false accusation and homicidal attempts. Assessment of burn injuries as well as rating permanent disabilities and disfigurement following thermal injuries for the benefit of compensation claims represents a challenging problem. This necessitates the development of reliable scoring systems to yield an expected likelihood of permanent disability or fatal outcome following burn injuries. The study was designed to identify the risk factors of mortality in acute burn patients and to evaluate the applicability of FLAMES (Fatality by Longevity, APACHE II score, Measured Extent of burn, and Sex) and BOBI (Belgian Outcome in Burn Injury) model scores in predicting the outcome. The study was conducted on 100 adult patients with acute burn injuries admitted to the Burn Unit of Alexandria Main University Hospital, Egypt from October 2014 to October 2015. Victims were examined after obtaining informed consent and the data were collected in specially designed sheets including demographic data, burn details and any associated inhalation injury. Each burn patient was assessed using both BOBI and FLAMES scoring systems. The results of the study show the mean age of patients was 35.54±12.32 years. Males outnumbered females (55% and 45%, respectively). Most patients were accidently burnt (95%), whereas suicidal burns accounted for the remaining 5%. Flame burn was recorded in 82% of cases. As well, 8% of patients sustained more than 60% of total burn surface area (TBSA) burns, 19% of patients needed mechanical ventilation, and 19% of burnt patients died either from wound sepsis, multi-organ failure or pulmonary embolism. The mean length of hospital stay was 24.91±25.08 days. The mean BOBI score was 1.07±1.27 and that of the FLAMES score was -4.76±2.92. The FLAMES score demonstrated an area under the receiver operating characteristic (ROC) curve of 0.95 which was significantly higher than that of the BOBI score (0.883). A statistically significant association was revealed between both predictive models and the outcome. The study concluded that both scoring systems were beneficial in predicting mortality in acutely burnt patients. However, the FLAMES score could be applied with a higher level of accuracy.

Keywords: BOBI, Burns, FLAMES, scoring systems, outcome.

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Authors: Catherine Portelli

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Felines, such as Panthera tigris, Panthera leo and Puma concolor, have become common residents in animal parks and zoos. They often sustain injuries from other felines within the same, or adjacent enclosures and from playing with items of enrichment and structures of the enclosure itself. These open wounds, and their treatments, are often challenging in veterinary practice, where feline-specific studies are lacking. This study is based on the author’s clinical experience gained while working at local animal parks in the past five years, and current evidence of hydrocolloid dressing applied to other species. Hydrocolloid dressing is used for secondary healing of chronic and acute wounds, where there is a considerable amount of tissue loss. The patients included in this study were sedated using medetomidine and ketamine every three to four days, for wound treatment and bandage change. Comparative studies of different techniques of open wound management will improve the healing process of exotic felines in the future by decreasing the time of recovery and incidence of other complications. Such studies will also aid with treatment of injuries sustained in wild felines, such as foot hold trap and bite wounds, found in natural conservation areas and wild animal sanctuaries.

Keywords: Felines, hydrocolloid dressing, open wound, secondary healing.

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Authors: Jefrey Pilusa, Tumisang Seodigeng

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This research discusses a South African case study for the potential of utilizing refuse-derived fuel (RDF) obtained from non-burn treatment of health care risk waste (HCRW) as potential feedstock for green energy production. This specific waste stream can be destroyed via non-burn treatment technology involving high-speed mechanical shredding followed by steam or chemical injection to disinfect the final product. The RDF obtained from this process is characterised by a low moisture, low ash, and high calorific value which means it can be potentially used as high-value solid fuel. Due to the raw feed of this RDF being classified as hazardous, the final RDF has been reported to be non-infectious and can blend with other combustible wastes such as rubber and plastic for waste to energy applications. This study evaluated non-burn treatment technology as a possible solution for on-site destruction of HCRW in South African private and public health care centres. Waste generation quantities were estimated based on the number of registered patient beds, theoretical bed occupancy. Time and motion study was conducted to evaluate the logistics viability of on-site treatment. Non-burn treatment technology for HCRW is a promising option for South Africa, and successful implementation of this method depends upon the initial capital investment, operational cost and environmental permitting of such technology; there are other influencing factors such as the size of the waste stream, product off-take price as well as product demand.

Keywords: Autoclave, disposal, fuel, incineration, medical waste.

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Authors: B. Roostaii, H. Kazeminejad, S. Khakshournia

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The evolution of volume porosity previously obtained by using the existing low temperature high burn-up gaseous swelling model with progressive recrystallization for UO₂ fuel is utilized to study the degradation of irradiated UO₂ thermal conductivity calculated by the FRAPCON model of thermal conductivity. A porosity correction factor is developed based on the assumption that the fuel morphology is a three-phase type, consisting of the as-fabricated pores and pores due to intergranular bubbles whitin UO₂ matrix and solid fission products. The predicted thermal conductivity demonstrates an additional degradation of 27% due to porosity formation at burn-up levels around 120 MWd/kgU which would cause an increase in the fuel temperature accordingly. Results of the calculations are compared with available data.

Keywords: Irradiation-induced recrystallization, matrix swelling, porosity evolution, UO2 thermal conductivity.

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Authors: Amany S. Youssef, Suzan A.M. El Feky, Samy A. El-Asser, Rasha A.M. Abd Allah

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Surgical site infections (SSIs) are the most common nosocomial infection in surgical patients resulting in significant increases in postoperative morbidity and mortality. The commonly causative bacteria developed resistance to virtually all antibiotics available. The aim of this study was to isolation and identification the most common bacteria that cause SSIs in Medical Research Institute, and to compare their sensitivity to selected group of antibiotics and natural products (garlic, oregano, olive, and Nigella sativa oils). The isolated pathogens collected from infected surgical wounds were identified, and their sensitivities to the antibiotics commonly available for clinical use, and also to the different concentrations of the used natural products were investigated. The results indicate to the potential therapeutic effect of the tested natural products in treatment of surgical wound infections.

Keywords: Surgical wounds, multi-resistant bacteria, bacterial sensitivity, natural oils.

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Authors: Dmitriy Yu. Korulkin, Raissa A. Muzychkina

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The article represents the results of clinical researches of composite herbal medicinal product based on essential oils of Sedum plants growing in Kazakhstan in commercial reserves at the territory of Kazakhstan. The results of comparative analysis are represented in obstetric-gynecologic practice during combined therapy for postnatal complications, inflammatory infiltrates in the area of surgical wounds including wounds after caesarean section.

Keywords: Anti-inflammatory, bioactive substances, essential oils, isolation, Sedum L., wound healing.

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Authors: Geun-Il Park, Jae-Won Lee, Dou-Youn Lee, Jung-Won Lee, Kwang-Wook Kim, Kee-Chan Song

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Thermochemcial characteristics of powder fabricated using oxidation treatment of spent PWR fuel and SIMFUEL were evaluated for recycling of spent fuel such as DUPIC process. Especially, the influence of spent fuel burn-ups on the powder fabrication characteristics was experimentally evaluated, ranging from 27,300 to 65,000 MWd/tU. Densities of powder manufactured from an oxidation, OREOX and the milling processes at the same process conditions were compared as a function of the fuel burn-ups respectively. Also, based on chemical analysis results, homogeneity of fissile elements in oxidized powder was confirmed.

Keywords: Spent PWR fuel, DUPIC, Oxidation, OREOX, Powder, Chemical analysis

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Authors: M. Sreedhar Babu, Vishal Garg, S. B. Akella, Shibu Clement, N. K. S Rajan

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Producer gas is a biomass derived gaseous fuel which is extensively used in internal combustion engines for power generation application. Unlike the conventional hydrocarbon fuels (Gasoline and Natural gas), the combustion properties of producer gas fuel are much different. Therefore, setting of optimal spark time for efficient engine operation is required. Owing to the fluctuating tendency of producer gas composition during gasification process, the heat release patterns (dictating the power output and emissions) obtained are quite different from conventional fuels. It was found that, valve lift timing is yet another factor which influences the burn rate of producer gas fuel, and thus, the heat release rate of the engine. Therefore, the present study was motivated to estimate the influence of valve lift timing analytically (Wiebe model) on the burn rate of producer gas through curve fitting against experimentally obtained mass fraction burn curves of several producer gas compositions. Furthermore, Wiebe models are widely used in zero-dimensional codes for engine parametric studies and are quite popular. This study also addresses the influence of hydrogen and methane concentration of producer gas on combustion trends, which are known to cause dynamics in engine combustion.

Keywords: Combustion Duration, crank angle, mass fraction burnt, producer gas, wiebe combustion model, wide open throttle.

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Authors: A. Panacek, M. Kilianova, R. Prucek, V. Husickova, R. Vecerova, M. Kolar, L. Kvitek, R. Zboril

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In this work we describe the preparation of NanoSilver/methylcellulose hydrogel containing silver nanoparticles (NPs) for topical bactericidal applications. Highly concentrated dispersion of silver NPs as high as of 5g/L of silver with diameter of 10nm was prepared by reduction of AgNO₃ via strong reducing agent NaBH₄. Silver NPs were stabilized by addition of sodium polyacrylate in order to prevent their aggregation at such high concentration. This way synthesized silver NPs were subsequently incorporated into methylcellulose suspension at elevated temperature resulting in formation of NanoSilver/methylcellulose hydrogel when temperature cooled down to laboratory conditions. In vitro antibacterial activity assay proved high bactericidal and fungicidal efficiency of silver NPs alone in the form of dispersion as well as in the form of hydrogel against broad spectrum of bacteria and yeasts including highly multiresistant strains such as methicillin-resistant Staphylococcus aureus. A very low concentrations of silver as low as 0.84mg/L Ag in as-prepared dispersion gave antibacterial performance. NanoSilver/methylcellulose hydrogel showed antibacterial action at the lowest used silver concentration equal to 25mg/L. Such prepared NanoSilver/methylcellulose hydrogel represent promising topical antimicrobial formulation for treatment of burns and wounds.

Keywords: Antimicrobial, burn, hydrogel, silver NPs.

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Authors: Fereshteh Shacheraghi, Mohammad Reza Shakibaie, Hanieh Noveiri

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Fourty one strains of ESBL producing P.aeruginosa which were previously isolated from burn patients in Kerman University general hospital, Iran were subjected to PCR, RFLP and sequencing in order to determine the type of extended spectrum β- lactamases (ESBL), the restriction digestion pattern and possibility of mutation among detected genes. DNA extraction was carried out by phenol chloroform method. PCR for detection of bla genes was performed using specific primer for each gene. Restriction Fragment Length Polymorphism (RFLP) for ESBL genes was carried out using EcoRI, NheI, PVUII, EcoRV, DdeI, and PstI restriction enzymes. The PCR products were subjected to direct sequencing of both the strands for identification of the ESBL genes.The blaCTX-M, blaVEB-1, blaPER-1, blaGES-1, blaOXA-1, blaOXA-4 and blaOXA-10 genes were detected in the (n=1) 2.43%, (n=41)100%, (n=28) 68.3%, (n=10) 24.4%, (n=29) 70.7%, (n=7)17.1% and (n=38) 92.7% of the ESBL producing isolates respectively. The RFLP analysis showed that each ESBL gene has identical pattern of digestion among the isolated strains. Sequencing of the ESBL genes confirmed the genuinety of PCR products and revealed no mutation in the restriction sites of the above genes. From results of the present investigation it can be concluded that blaVEB-1 and blaCTX-M were the most and the least frequently isolated ESBL genes among the P.aeruginosa strains isolated from burn patients. The RFLP and sequencing analysis revealed that same clone of the bla genes were indeed existed among the antibiotic resistant strains.

Keywords: ESBL genes, PCR, RFLP, Sequencing, P.aeruginosa

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Authors: Marzhan Baimurzayeva, Alibek Utyanov, Gulnar Shabdarbaeva, Damir Khussainov

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This article introduces the actual problem that is а study of proposed by the authors Hydrocele ointment in amino acids’ metabolism of cows’ blood in inflammation of traumatic origin. Hydrocele ointment has shown a positive effect on inflammatory process and amino acids’ metabolism of animals treated with the drug. Amino acid levels reached physiological parameters on the 10th day after treatment; in the control group this parameter was higher than normal.

Keywords: Amino acids, blood protein, Hydrocele ointment, inflammation, repair.

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Authors: Proud Arunrangsiwed

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This study analyzes the crisis management and image repair strategies during the crisis of Mahidol Wittayanusorn School (MWIT) library burning. The library of this school was burned by a 16-year-old-male student on June 6th, 2010. This student blamed the school that the lesson was difficult, and other students were selfish. Although no one was in the building during the fire, it had caused damage to the building, books and electronic supplies around 130 million bahts (4.4 million USD). This event aroused many discourses arguing about the education system and morality. The strategies which were used during crisis were denial, shift the blame, bolstering, minimization, and uncertainty reduction. The results of using these strategies appeared after the crisis. That was the numbers of new students, who registered for the examination to get into this school in the later years, have remained the same.

Keywords: School, crisis management, violence, image repair strategies, uncertainty, burn.

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Authors: Fridhi Hadia, Soua Wadhah, Hidouri Ammar, Omri Ahmed

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In this research, the effects of the engine parameters like compression ratios and steam injection on igniting timing and emission characteristics have been investigated numerically. The in-cylinder temperature and pressure at four different compression ratios have been compared with numerical results, and they show a good agreement with the published data. Two different fuels have been used in this study: Isooctane (IC₈H₁₈), and ethanol (C₂H₅OH). The increasing of the compression ratio (CR) advances the ignition timing, decreases the burn duration and increases the temperature and the pressure. The injection of water vapor lower than 40% decreased the peak temperature and slowed the combustion rate which leads to a lower NOx emission.

Keywords: Compression ratio, emission, HCCI engine, ignition timing, steam injection.

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Authors: Darren Thompson, Philip Morrow, Bryan Scotney, John Winder

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Patients with diabetes are susceptible to chronic foot wounds which may be difficult to manage and slow to heal. Diagnosis and treatment currently rely on the subjective judgement of experienced professionals. An objective method of tissue assessment is required. In this paper, a data fusion approach was taken to wound tissue classification. The supervised Maximum Likelihood and unsupervised Multi-Modal Expectation Maximisation algorithms were used to classify tissues within simulated wound models by weighting the contributions of both colour and 3D depth information. It was found that, at low weightings, depth information could show significant improvements in classification accuracy when compared to classification by colour alone, particularly when using the maximum likelihood method. However, larger weightings were found to have an entirely negative effect on accuracy.

Keywords: Classification, data fusion, diabetic foot, stereophotogrammetry, tissue colour.

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Authors: Pinfa Boonrong, Boonserm Kaewkamnerdpong

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As nanotechnology advances, the use of nanotechnology for medical purposes in the field of nanomedicine seems more promising; the rise of nanorobots for medical diagnostics and treatments could be arriving in the near future. This study proposes a swarm intelligence based control mechanism for swarm nanorobots that operate as artificial platelets to search for wounds. The canonical particle swarm optimization algorithm is employed in this study. A simulation in the circulatory system is constructed and used for demonstrating the movement of nanorobots with essential characteristics to examine the performance of proposed control mechanism. The effects of three nanorobot capabilities including their perception range, maximum velocity and respond time are investigated. The results show that canonical particle swarm optimization can be used to control the early version nanorobots with simple behaviors and actions.

Keywords: Artificial platelets, canonical particle swarm optimization, nanomedicine, nanorobot, swarm intelligence.

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Authors: Uzu-Kuei Hsu, Keh-Chin Chang, Joo-Guan Hang

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Carbon Deposits are often occurred inside the industrial coke oven during coking process. Accumulation of carbon deposits may cause a big issue, which seriously influences the coking operation. The carbon is burning off by injecting fresh air through pipes into coke oven which is an efficient way practically operated in industries. The burning off carbon deposition in coke oven performed by Computational Fluid Dynamics (CFD) method has provided an evaluation of the feasibility study. A three dimensional, transient, turbulent reacting flow simulation has performed with three different injecting air flow rate and another kind of injecting configuration. The result shows that injection higher air flow rate would effectively reduce the carbon deposits. In the meantime, the opened charging holes would suck extra oxygen from atmosphere to participate in reactions. In term of coke oven operating limits, the wall temperatures are monitored to prevent over-heating of the adiabatic walls during burn-off process.

Keywords: Coke oven, burning off, carbon deposits, carbon combustion, CFD.

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Authors: L. Lundgren, S. Brorsson, A-L Osvalder

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Participation in sporting activities can lead to injury. Sport injuries have been widely studied in many sports including the more extreme categories of aquatic board sports. Kitesurfing is a relatively new water surface action sport, and has not yet been widely studied in terms of injuries and stress on the body. The aim of this study was to get information about which injuries that are most common among kitesurfing participants, where they occur, and their causes. Injuries were studied using an international open web questionnaire (n=206). The results showed that many respondents reported injuries, in total 251 injuries to knee (24%), ankle (17%), trunk (16%) and shoulders (10%), often sustained while doing jumps and tricks (40%). Among the reported injuries were joint injuries (n=101), muscle/tendon damages (n=47), wounds and cuts (n=36) and bone fractures (n=28). Also environmental factors and equipment can influence the risk of injury, or the extent of injury in a hazardous situation. Conclusively, the information from this retrospective study supports earlier studies in terms of prevalence and site of injuries. Suggestively, this information should be used for to build a foundation of knowledge about the sport for development of applications for physical training and product development.

Keywords: Kitesurfing, injuries, injury cause, questionnaire.

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Authors: Ioan Rusu

Abstract:

In the operation of power transformers of 110 kV/MV from substations, these are traveled by fault current resulting from MV line damage. Defect electrical contacts are heated when they are travelled from fault currents. In the case of high temperatures when 135 °C is reached, the electrical insulating oil in the vicinity of the electrical faults comes into contact with these contacts releases gases, and activates the electrical protection. To avoid auto-flammability of electro-insulating oil, we designed a security system thermal of electrical contact defects by pouring fire-resistant polyurethane foam, mastic or mortar fire inside a cardboard electro-insulating cylinder. From practical experience, in the exploitation of power transformers of 110 kV/MT in oil electro-insulating were recorded some passing disconnecting commanded by the gas protection at internal defects. In normal operation and in the optimal load, nominal currents do not require thermal secure contacts inside electrical transformers, contacts are made at the fabrication according to the projects or to repair by solder. In the case of external short circuits close to the substation, the contacts inside electrical transformers, even if they are well made in sizes of Rcontact = 10^‑6 Ω, are subjected to short-circuit currents of the order of 10 kA-20 kA which lead to the dissipation of some significant second-order electric powers, 100 W-400 W, on contact. At some internal or external factors which action on electrical contacts, including electrodynamic efforts at short-circuits, these factors could be degraded over time to values in the range of 10^-4 Ω to 10^-5 Ω and if the action time of protection is great, on the order of seconds, power dissipation on electrical contacts achieve high values of 1,0 kW to 40,0 kW. This power leads to strong local heating, hundreds of degrees Celsius and can initiate self-ignition and burning oil in the vicinity of electro-insulating contacts with action the gas relay. Degradation of electrical contacts inside power transformers may not be limited for the duration of their operation. In order to avoid oil burn with gas release near electrical contacts, at short-circuit currents 10 kA-20 kA, we have outlined the following solutions: covering electrical contacts in fireproof materials that would avoid direct burn oil at short circuit and transmission of heat from electrical contact along the conductors with heat dissipation gradually over time, in a large volume of cooling. Flame retardant materials are: polyurethane foam, mastic, cement (concrete). In the normal condition of operation of transformer, insulating of conductors coils is with paper and insulating oil. Ignition points of its two components respectively are approximated: 135 °C heat for oil and 200 ⁰C for paper. In the case of a faulty electrical contact, about 10^-3 Ω, at short-circuit; the temperature can reach for a short time, a value of 300 °C-400 °C, which ignite the paper and also the oil. By burning oil, there are local gases that disconnect the power transformer. Securing thermal electrical contacts inside the transformer, in cardboard tube with polyurethane foams, mastik or cement, ensures avoiding gas release and also gas protection working.

Keywords: Power transformer, oil insulatation, electric contacts, gases, gas relay.

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Authors: Magda Bădescu, Daniela Jitaru, C.Grigoraş, L.Bădescu, I. Topala, Manuela Ciocoiu

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The purpose of our study was to compare spontaneous re-epithelisation characteristics versus assisted re-epithelisation. In order to assess re-epithelisation of the injured skin, we have imagined and designed a burn wound model on Wistar rat skin. Our aim was to create standardised, easy reproducible and quantifiable skin lesions involving entire epidermis and superficial dermis. We then have applied the above mentioned therapeutic strategies to compare regeneration of epidermis and dermis, local and systemic parameter changes in different conditions. We have enhanced the reepithelisation process under a moist atmosphere of a polyurethane wound dress modified with helium non-thermal plasma, and with the aid of direct cold-plasma treatment respectively. We have followed systemic parameters change: hematologic and biochemical parameters, and local features: oxidative stress markers and histology of skin in the above mentioned conditions. Re-epithelisation is just a part of the skin regeneration process, which recruits cellular components, with the aid of epidermal and dermal interaction via signal molecules.

Keywords: Plasma medicine, re-epithelisation and tissue regeneration

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Authors: Siyamak Ziyaei, Siti Khalijah Mazlan, Petros Lappas

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Compressed natural gas (CNG) is primarily composed of methane (CH4), and has a lower carbon to hydrogen ratio than other hydrocarbon fuels such as gasoline (C8H18) and diesel (C12H23). Consequently, it has the potential to reduce CO2 emissions compared to conventional fuels. Although Natural Gas (NG) has environmental advantages compared to other hydrocarbon fuels, its main component, CH4, burns at a slower rate compared to the conventional fuels. A higher pressure and leaner cylinder environment will unravel the slow burn characteristic of CH4. Lean combustion and high compression ratios are well-known methods for increasing the efficiency of internal combustion engines. In order to achieve successful a CNG lean combustion in Spark Ignition (SI) engines, a strong ignition system is essential to avoid engine misfires, especially in ultra-lean conditions. Turbulent Jet Ignition (TJI) is an ignition system that employs a pre-combustion chamber to ignite the lean fuel mixture in the main combustion chamber using a fraction of the total fuel per cycle. TJI enables ultra-lean combustion by providing distributed ignition sites through orifices. The fast burn rate provided by TJI enables the ordinary SI engine to be comparable to other combustion systems such as Homogeneous Charge Compression Ignition (HCCI) or Controlled Auto-Ignition (CAI) in terms of thermal efficiency, through the increased levels of dilution without the need of sophisticated control systems. Due to the physical geometry of TJI, which contains small orifices that connect the pre-chamber to the main chamber, providing the right mixture of fuel and air has been identified as a key challenge due to the insufficient amount of air that is pushed into the pre-chamber during each compression stroke. There is also the problem of scavenging which contributed to the factors that reduces the TJI performance. Combustion residual gases such as CO2, CO and NOx from the previous combustion cycle dilute the pre-chamber fuel-air mixture preventing rapid combustion in the pre-chamber. An air-controlled active TJI is presented in this paper in order to address these issues. By supplying air into the pre-chamber at a sufficient pressure, residual gases are exhausted, and the air-fuel ratio is controlled within the pre-chamber, thereby improving the quality of the combustion. An investigation of the 3D combustion characteristics of a CNG-fueled SI engine using a direct injection fuelling strategy employing an air channel in the prechamber is presented in this paper. Experiments and simulations were performed at the Worldwide Mapping Point (WWMP) at 1500 revolutions per minute (rpm), 3.3 bar Indicated Mean Effective Pressure (IMEP), using only conventional spark plugs as a baseline. With a validated baseline engine simulation, the settings were set for all simulation scenarios at λ=1. Following that, the pre-chambers with and without an auxiliary fuel supply were simulated. In the study of (DI-CNG) SI engine, active TJI was observed to perform better than passive TJI and conventional  spark plug ignition. In conclusion, the active pre-chamber with an air channel demonstrated an improved thermal efficiency (ηth) over other counterparts and conventional spark ignition systems.

Keywords: Turbulent Jet Ignition, Active Air Control Turbulent Jet Ignition, Pre-chamber ignition system, Active and Passive Pre-chamber, thermal efficiency, methane combustion, internal combustion engine combustion emissions.

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Authors: M R Asadi, G Torkaman, M Hedayati

Abstract:

We evaluated the effect of sensory (direct current (DC), 600μA) and motor (monophasic current, pulse duration 300μs, 100 Hz, 2.5-3mA) intensities of cathodal electrical stimulation (ES) current to release VEGF and biomechanical properties of wound. 54 male Sprague-dawley rats were randomly assigned into one control and two experimental groups. A full thickness skin incision was made on animals- dorsal region. The experimental groups received ES for 1h/day and every other day. VEGF expression was measured in skin on the 7th day after surgical incision and tensile strength was measured on 21st day. On the 7th day, the values of skin VEGF in the sensory group were significantly greater than those of the other groups (p < 0.05). Sensory and Motor intensity stimulation, can not improve the biomechanical properties of the repaired wounds. It seems the mechanical environment induced by sensory and motor intensity of electrical stimulation, could not simulate the role of normal daily stress and strain to maturation of collagen fibers and their cross links. Further work is needed to determine the relationship between VEGF expression after ES and its effect on tensile strength of healed wound.

Keywords: Biomechanical properties Direct current, Monophasic current, Skin, VEGF

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Authors: Abbas Alli Taghipoor Bafghi, Hosein Bakhoda, Fateme Khodaei Chegeni

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An experimental investigation is carried out to establish the performance characteristics of a compression ignition engine while using cerium oxide nanoparticles as additive in neat diesel and diesel-biodiesel blends. In the first phase of the experiments, stability of neat diesel and diesel-biodiesel fuel blends with the addition of cerium oxide nanoparticles is analyzed. After series of experiments, it is found that the blends subjected to high speed blending followed by ultrasonic bath stabilization improves the stability. In the second phase, performance characteristics are studied using the stable fuel blends in a single cylinder four stroke engine coupled with an electrical dynamometer and a data acquisition system. The cerium oxide acts as an oxygen donating catalyst and provides oxygen for combustion. The activation energy of cerium oxide acts to burn off carbon deposits within the engine cylinder at the wall temperature and prevents the deposition of non-polar compounds on the cylinder wall results reduction in HC emissions. The tests revealed that cerium oxide nanoparticles can be used as additive in diesel and diesel-biodiesel blends to improve complete combustion of the fuel significantly.

Keywords: Diesel engine, cerium oxide, diesel-biodiesel blends, nanoparticles.

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Authors: M. Sivakumar, D. Chamundeeswari

Abstract:

Glycosmis pentaphylla is one of the medicinally important plants belonging to the family Rutaceae, commonly known as “Anam or Panal” in Tamil. Traditionally, leaves are useful in fever, hepatopathy, eczema, skin disease, helminthiasis, wounds, and erysipelas. The fruits are sweet and are useful in vitiated conditions of vata, kapha, cough, and bronchitis. The roots are good for facial inflammations, rheumatism, jaundice, and anemia. The preliminary phytochemical investigations indicated the presence of alkaloids, terpenoids, flavonoids, tannins, sugar, glycoside, and phenolic compounds. In the present study, the root part of Glycosmis pentaphylla was used, and the root was collected from Western Ghats of South India. The root was sun/shade dried and pulverized to powder in a mechanical grinder. The powder was successively extracted with various solvents, and the ethyl acetate extract of Glycosmis pentaphylla has been subjected to the GC-MS analysis. Amongst the 46 chemical constituents identified from this plant, three major phytoconstituents were reported for the first time. Marmesin, a furanocumarin compound with the chemical structure 7H-Furo (3,2-G) (1)Benzopyran-7-one,2,3–dihydro–2 - (1-Hydroxy-1methylethyl)-(s) is one of the three compounds identified for the first time at the concentration of 11-60% in ethyl acetate extract of Glycosmis pentaphylla. Others include, Beta.-Fagarine (4.71%) and Paverine (13.08%).

Keywords: Ethyl acetate extract, Glycosmis pentaphylla, GC-MS analysis, phytochemicals.

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Authors: J. R. Wang, H. T. Lin, H. C. Chang, W. K. Lin, W. Y. Li, C. Shih

Abstract:

This analysis of Kuosheng nuclear power plant (NPP) was performed mainly by TRACE, assisted with FRAPTRAN and FRAPCON. SNAP v2.2.1 and TRACE v5.0p3 are used to develop the Kuosheng NPP SPU TRACE model which can simulate the turbine trip without bypass transient. From the analysis of TRACE, the important parameters such as dome pressure, coolant temperature and pressure can be determined. Through these parameters, comparing with the criteria which were formulated by United States Nuclear Regulatory Commission (U.S. NRC), we can determine whether the Kuoshengnuclear power plant failed or not in the accident analysis. However, from the data of TRACE, the fuel rods status cannot be determined. With the information from TRACE and burn-up analysis obtained from FRAPCON, FRAPTRAN analyzes more details about the fuel rods in this transient. Besides, through the SNAP interface, the data results can be presented as an animation. From the animation, the TRACE and FRAPTRAN data can be merged together that may be realized by the readers more easily. In this research, TRACE showed that the maximum dome pressure of the reactor reaches to 8.32 MPa, which is lower than the acceptance limit 9.58 MPa. Furthermore, FRAPTRAN revels that the maximum strain is about 0.00165, which is below the criteria 0.01. In addition, cladding enthalpy is 52.44 cal/g which is lower than 170 cal/g specified by the USNRC NUREG-0800 Standard Review Plan.

Keywords: Turbine trip without bypass, Kuosheng NPP, TRACE, FRAPTRAN, SNAP animation.

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Authors: Mohammed Sharif, Donald Burn

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Large scale climate signals and their teleconnections can influence hydro-meteorological variables on a local scale. Several extreme flow and timing measures, including high flow and low flow measures, from 62 hydrometric stations in Canada are investigated to detect possible linkages with several large scale climate indices. The streamflow data used in this study are derived from the Canadian Reference Hydrometric Basin Network and are characterized by relatively pristine and stable land-use conditions with a minimum of 40 years of record. A composite analysis approach was used to identify linkages between extreme flow and timing measures and climate indices. The approach involves determining the 10 highest and 10 lowest values of various climate indices from the data record. Extreme flow and timing measures for each station were examined for the years associated with the 10 largest values and the years associated with the 10 smallest values. In each case, a re-sampling approach was applied to determine if the 10 values of extreme flow measures differed significantly from the series mean. Results indicate that several stations are impacted by the large scale climate indices considered in this study. The results allow the determination of any relationship between stations that exhibit a statistically significant trend and stations for which the extreme measures exhibit a linkage with the climate indices.

Keywords: flood analysis, low-flow events, climate change, trend analysis, Canada

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Authors: Zhiwen Yang, Jingyuan Li, Zhenkai Xie, Jian Ling, Jiguang Wang, Mengliang Li

Abstract:

To reflect the influence of after-treatment system retrofit and natural gas-fueled vehicle replace on exhaust emissions emitted by urban buses, a portable emission measurement system (PEMS) was employed herein to conduct real driving emission measurements. This study investigated the differences in particle number (PN), particle mass (PM), and nitrogen oxides (NOx) emissions from a China IV diesel bus retrofitted by catalyzed diesel particulate filter (CDPF), a China IV diesel bus, and a China V natural gas bus. The results show that both tested diesel buses possess markedly advantages in NOx emission control when compared to the lean-burn natural gas bus equipped without any NOx after-treatment system. As to PN and PM, only the DOC+CDPF retrofitting diesel bus exhibits enormous benefits on emission control related to the natural gas bus, especially the normal diesel bus. Meanwhile, the differences in PM and PN emissions between retrofitted and normal diesel buses generally increase with the increase in vehicle specific power (VSP). Furthermore, the differences in PM emissions, especially those in the higher VSP ranges, are more significant than those in PN. In addition, the maximum peak PN particle size (32 nm) of the retrofitted diesel bus was significantly lower than that of the normal diesel bus (100 nm). These phenomena indicate that the CDPF retrofitting can effectively reduce diesel bus exhaust particle emissions, especially those with large particle sizes.

Keywords: CDPF, diesel, natural gas, real-world emissions.

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Authors: Saleem Z. Ramadan

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A model is presented to find the optimal design of the mixed renewable warranty policy for non-repairable Weibull life products. The optimal design considers the conflict of interests between the customer and the manufacturer: the customer interests are longer full rebate coverage period and longer total warranty coverage period, the manufacturer interests are lower warranty cost and lower risk. The design factors are full rebate and total warranty coverage periods. Results showed that mixed policy is better than full rebate policy in terms of risk and total warranty coverage period in all of the three bathtub regions. In addition, results showed that linear policy is better than mixed policy in infant mortality and constant failure regions while the mixed policy is better than linear policy in ageing region of the model. Furthermore, the results showed that using burn-in period for infant mortality products reduces warranty cost and risk.

Keywords: Reliability, Mixed warranty policy, Optimization, Weibull Distribution.

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