We report a case of severe burn injury in a 42-year-old pregnant patient referred to our hospital's burn unit after experiencing a scald burn injury that burned her neck, chest, trunk, abdomen and ...limbs. The patient had burn wounds distributed on her neck, all four extremities, the chest and abdomen, with a total burn area of 46.5%. The burn wounds were treated with surgical debridement and then covered with silver sulfadiazine and damp gauze. The patient's wounds were treated every three days. The patient delivered a healthy baby full-term through a spontaneous, vaginal delivery. After delivery, the amniotic membrane from the patient was used as an amniotic membrane graft and was planted on the patient's chest, right arm and right thigh. The amniotic membrane in this patient helped to accelerate the preparation of the wound bed for skin grafting. Split-thickness skin grafts were then used on the wounds and the patient was discharged from the hospital one week later. Patients that present with burn injuries during pregnancy require intense monitoring and careful management from a multidisciplinary team. A collaborative effort needs to be made in order to plan the best outcome for the mother and fetus. Precise and early resuscitation is the first step to treating such cases. The administration of fluids should be titered based on the patient's hemodynamic condition and urine output. Wound management can also be optimized using the amniotic membrane as a temporary dressing before skin grafting.
In industrial application,unintentional manufacturing line troubles often consequence in heating raw materials excessively,in terms of either time or temperature.One of the effects of such occurrence ...is a product with a variation of prior austenite grain size,even if after the heat treatment the end result is the same,martensite.The variation of the prior austenite grain size is believed to vary the end results of the martensite.This undesirable variation includes the variation of fatigue resistance,impact strength,yield strength,hardness,etc.This research studies the effect of the prior austenite grain size on the morphology of the martensite microstructure.The results show that within the typical industrial application of temperature and holding time set up,as holding time or the temperature increases,the prior austenite average diameter increases.The block and packet sizes in the martensite also increase.The variation of mechanical property dependence on the grain size is indeed due to the different characteristics reflected in the martensite morphology.With respect to the same area,smaller grain has more blocks and packets,which agrees with higher dislocation density verified with transmission electron microscopic evaluation.
Cattle and buffalo have different characteristic in utilizing of feed protein. The differences of utilization will impact on N excretion in feces and urine which are potential to increase ...environmental contamination. Therefore, it was necessary to evaluate the N emission factor and to determine the specific management that suitable for each commodity species. Total of 26 individual data were obtained from 2 studies in nitrogen balance trials (11 heads of cattle and 15 heads of buffalo). All data were observed from total collection method. The value of nitrogen content in feces and urine were analyzed by Kjedhal method. The parameters observed in this study were nitrogen intake, nitrogen faeces and urine. The data were analyzed using t-test. The results showed that higher N intake/metabolic BW, the higher N excretion, both of urine and feces on buffalo and cattle. In the same intake/metabolic BW, buffalo excreted higher feces than cattle. However, different result was shown in N urine excretion. N urine excretion on buffalo was lower than cattle. N intake/metabolic BW has positive and strong correlation with all N feces excretion (r = 0.89) but low correlation with all N urine excretion (r = 0.36). It can be concluded that buffalo was more environmentally friendly than cattle due to lower nitrogen urine excretion.
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► Continuum mechanics based approximation is too often unsatisfactory for real material’s problems. ► Deterministic analyses often produce inconclusive, or conflicting, in estimating ...the fatigue life of a component. ► Cracks are described better with fractal mathematics than with Euclidean mathematics. ► Possibility of the applications of probabilistic and fractal fracture mechanics is predicted.
Continuum mechanics-based approximation is too often unsatisfactory for solution of real material problems especially in experimental as well as computational fatigue applications. Various methods of classical-deterministic analyses often produce inconclusive or conflicting estimates of the fatigue life of a component. In addition, the classical Griffith–Irwin–Orowan concept that assumed the phenomena based on homeomorphism mathematics cannot be developed any closer to the experimental results anymore. It has already reached its saturation point. This note discusses the fundamental reasons of the limitations of classical fracture mechanics and subsequently predicts alternatives. Application of classical fracture mechanics to engineering problems is discussed along with possible alternatives employing probabilistic and fractal fracture mechanics in materials engineering.
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► This technical note discusses about traditional rule of mixture and homogenization. ► The techniques were applied to austenitic steel with possible configuration of nine phases. ► ...It was found that the homogenization technique was capable in capturing the orthotropic characteristics of austenite.
This is a technical note highlighting a method on how to perform averaging the elastic properties. The drawback of the traditional rule of mixture (ROM) is briefly discussed. The technique considers the effect of morphology based on classical continuum mechanics, taking the advantages of fracture mechanics. As an example, a model that simulates the possible configuration of constituting phases commonly found in austenite microstructure is chosen. The result is compared with traditional ROM. It is found that although similar, the result is better due to the stress amplification that is accommodated in the method, unlike the traditional ROM, which merely considers only the volumetric ratio.
It is well known that decarburization has a bad effect on spring steel strength. This research presents a method to improve the product quality by means of recovering the decarburization layer. ...Unlike conventional methods, which usually use mechanical means, this method relies on a basic metallurgical principle, the process of diffusion. A carbon-rich layer is coated on the surface of the object. The object is then heat treated at conditions similar to the manufacturing process. To accomplish the objective, an experiment and a finite-element analysis (FEA) simulation were performed. The material chosen was a hypo-eutectoid steel with an excessive decarburization layer. The simulation was performed by digitizing the optical micrograph of decarburized raw materials and meshing the picture to get elements to start the analysis. Simple diffusion theory was then applied to the model. Various time parameters were used to simulate the redistribution of the carbon atoms. Comparable with the simulation, an experiment was also performed. The experiment began by coating a carbon-rich material onto decarburized raw material. The samples were then austenitized and subsequently either annealed or quenched. The state of the carbon restoration was then evaluated. The research concluded that the idea of carbon restoration can be implemented in the manufacturing process.
The use of fracture mechanics outside the area of mechanics, including materials science, is evidence that the concept is capable of handling failures involving almost any types of crack ...propagations. This paper outlines the simple method on how to use fracture mechanics concepts in coating study by using a concrete example that is easy to follow. The example presented here is the use of fracture mechanics to develop equation governing the blister propagation using the concept pioneered by Sih, the SED concept. Despite being simple, the method gives excellently good agreement with those available solutions derived by other methods.
We report a case of severe burn injury in a 42-year-old pregnant patient referred to our hospital's burn unit after experiencing a scald burn injury that burned her neck, chest, trunk, abdomen and ...limbs. The patient had burn wounds distributed on her neck, all four extremities, the chest and abdomen, with a total burn area of 46.5%. The burn wounds were treated with surgical debridement and then covered with silver sulfadiazine and damp gauze. The patient's wounds were treated every three days. The patient delivered a healthy baby full-term through a spontaneous, vaginal delivery. After delivery, the amniotic membrane from the patient was used as an amniotic membrane graft and was planted on the patient's chest, right arm and right thigh. The amniotic membrane in this patient helped to accelerate the preparation of the wound bed for skin grafting. Split-thickness skin grafts were then used on the wounds and the patient was discharged from the hospital one week later. Patients that present with burn injuries during pregnancy require intense monitoring and careful management from a multidisciplinary team. A collaborative effort needs to be made in order to plan the best outcome for the mother and fetus. Precise and early resuscitation is the first step to treating such cases. The administration of fluids should be titered based on the patient's hemodynamic condition and urine output. Wound management can also be optimized using the amniotic membrane as a temporary dressing before skin grafting.
One of the principles of radiation protection is optimizing radiation dose and image quality. Dose audits and optimization of head CT scans for the adult patient category have been carried out in ...Hospital A and Hospital B. The research at Hospital A started with a dose audit, revealing that the typical values of CTDIvol and DLP were above the IDRL, and optimization of patient radiation dose was necessary. The optimization strategy at Hospital A involved a gradual selection of exposure factor combinations. In the first stage, a manufactured dedicated water phantom scan was performed with voltage 80, 100, and 120 kVp variations while the current remained constant. Based on image quality evaluation using the Noise Power Spectrum (NPS) method, the lowest NPS was obtained at voltage 120 kV, which was 19,47 HU2mm2. In the second stage, using voltage 120 kVp, a head rando phantom scan was performed with variations of current 100, 150, 200, 250, 300, 350, 400, and 450 mAs. 40% of the radiologists chose the exposure factor combination voltage 120 kVp and current 350 mAs as the combination producing image with the most preferable quality. When comparing the voltage and current combinations before and after optimization with the IDRL, there was a decrease of 7.9% and 2.1% in CTDIvol and DLP. Meanwhile, the dose audit results at Hospital B revealed that the typical value of CTDIvol was already below the IDRL. Still, the typical value of DLP was above the IDRL, so optimization of patient radiation dose for patient-related parameters was necessary. The optimization strategy at Hospital B involved creating new protocols based on exposure factors obtained from image quality evaluation using the NPS method and the interpretation of radiologists. The optimization results with a comparison of four protocols showed that protocol 3 was the most optimal using the exposure factors: collimation 40 × 0.625, the pitch of 0.2, the scan time of 13.8 seconds, Dose Right Index of 25, voltage 120 kVp, and current 144 mAs. The implementation of this protocol contributed to a 67.7% reduction in CTDIvol and a 53.6% reduction in DLP compared to the IDRL. The research objective is to obtain the optimal combination of exposure factors with radiation dosage and image quality as an initial optimization implementation. Keywords: dose audit, radiation protection, optimization, diagnostic reference levels
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