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This paper assesses the impact of changing the available multiple process plans of a job type in a production order on mean tardiness using simulation based genetic algorithm approach. A restart scheme as suggested in the literature is embedded into genetic algorithm in order to prevent premature convergence. An algorithm is developed to select a job type that becomes a candidate in order to change the available multiple process plans. Three case studies of varying sizes have been considered to assess the performance of job shop with an objective to minimise mean tardiness. Results indicate that by changing the available multiple process plans of a job type in a production order assists in reducing mean tardiness of a production order. In addition, selecting the best process plan among available multiple process plans on the basis of minimum total production time criterion for a job type does not yield optimal schedule. [ABSTRACT FROM AUTHOR]

A seven-year-old child with an airgun pellet injury to the upper part of the anterior chest wall was transported in a state of shock from a nearby hospital to this trauma centre. The nature and site of injury associated with engorged neck veins, hypotension, pulsus paradoxus and an enlarged liver suggested the possibility of acute pericardial tamponade. On arrival in the emergency room the child had a brief period of cardiac arrest revived by basic resuscitation procedures. Pericardiocentesis was negative in the emergency room. Emergency median sternotomy with pericardiotomy was done to relieve the tamponade which was peroperatively diagnosed to be due to a tear in the pulmonary artery close to its origin. Early clinical diagnosis, rapid surgical intervention in the operating room and efficient anaesthetic management within the ‘Golden Hour’ saved life. It is believed that this is the first report of survival of a paediatric patient with a gunshot penetrating trauma to the pulmonary artery leading to cardiac tamponade and a brief period of cardiac arrest. [ABSTRACT FROM AUTHOR]

The present paper identifies the different process parameters that effect the cutting speed and surface roughness in wire electrical discharge machining of Titanium-6-2-4-2 (HSTR aerospace alloy), which is so far not reported in the literature. It also identifies optimal process parameter combination for simultaneous optimization of cutting speed and surface roughness to be presented as a guideline for machining of Titanium-6-2-4-2. Box-Behnken design and response surface methodology are used to plan and analyse the experiments. Six control factors viz. Pulse on time, pulse off time, peak current, spark gap set voltage, wire feed, and wire tension are chosen as process parameters to study the performance of the process in terms of cutting speed and surface roughness. The recommended optimal parameter combinations have been verified by conducting confirmation experiments. [ABSTRACT FROM AUTHOR]

Background: When using morphine as the sole analgesic during conduct of anesthesia, the fear of its adverse postoperative effects primarily sedation and respiratory depression may impede adequate dosing and analgesia. Aim and Objectives: This audit aims to explore the dosing schedules of morphine used during general anesthesia in our institution and to analyze whether the fear of major side effects leads to suboptimal dosing of morphine with inadequate pain relief. Materials and Methods: All subjects scheduled for surgery under general anesthesia wherein morphine was used exclusively for intraoperative analgesia were included in the audit. The audit proforma was completed by the attending anesthesiologist wherein the study period extended from beginning of anesthesia to immediate postoperative period. Result: The study population comprised of 158 patients having mean age 33 ± 14 years and mean weight 52 ± 14 kg. The dose of morphine administered at induction varied widely from 0.05 to 0.3 mg/kg i.v. The VAS (Visual Analogue Scale) score in immediate postoperative period varied from 0 to 10 (mean 1.7 ± 2.0) and sedation score from 1 to 5 (mean 3.94 ± 1.05). Inadequate analgesia with a VAS score =4 was seen in 15% patients. Morphine dosage of >0.1 mg/kg was associated with highly significant increase in quality of postoperative analgesia with VAS score <4, and an increase in sedation with sedation score =3 (P value < 0.01). However, none of the patients required active intervention for cardiorespiratory support. Conclusion: The practice of dosing morphine in our institution is highly variable with doses ranging from 0.05 to 0.3 mg/ kg. This results in inadequate analgesia in 15% patients in postoperative period. Titrating the dose of morphine to expected pain levels inflicted upon by surgical procedures may result in better pain control and less sedated patients postoperatively. [ABSTRACT FROM AUTHOR]

Process planning and scheduling are the two important manufacturing functions involved in any shop floor activities. As functional integration is essential to realize the benefits of computer integrated manufacturing, a scheme for integration of process planning and scheduling has been introduced in this paper. The proposed scheme can be implemented in a company with existing process planning and scheduling departments when multiple process plans remain available on the shop floor. It consists of two main modules, introduced in detail in this paper. They are process plan selection module and scheduling module. [ABSTRACT FROM AUTHOR]

This paper presents investigation of surface veracity of Wire EDM machined surfaces of Al / ZrO 2 (p) - MMC obtained utilizing the optimal parametric combinations. The effect of process parameters on the desired performance characteristics, i.e., minimum spark gap (SG), maximum material removal rate (MRR) and minimum surface roughness [SR( R a & R t )], is also presented. The second-order numerical expressions developed by response surface methodology (RSM) are used as a function in.M file. Genetic Algorithm and Direct Search Toolbox of MATLAB ® are utilized to identify the multi-objective optimum set of the process parameters for the desired performance characteristics. In the present paper, surface veracity aspects that include surface defects and thickness of recast layer are investigated for the machined surfaces obtained after Wire EDM to achieve the desired optimum performance characteristics. From the investigation, it can safely be concluded that for the Wire EDM of Al / ZrO 2 (p) - MMC s, lower parameter setting values of pulse width and short pulse time along with higher parameter setting value of time between pulses are desirable from the view point of good surface veracity of the machined surfaces as well as to obtain low average recast layer thickness ( Rl tavg ). The Rl tavg decreases as weight fraction of ZrO 2 (p) increases in Al / ZrO 2 (p) - MMC from 5 to 15%. The investigation of surface veracity of the Wire EDM obtained surfaces will provide the significant guidelines to the production engineers to plan the need of subsequent operations to improve the surface veracity and further the life of the products fabricated using these MMCs. [ABSTRACT FROM AUTHOR]

This paper presents an experimental investigation of the machining characteristics and the effect of wire electrical discharge machine process parameters during machining of newly developed Al/10 % ZrO metal matrix composite (MMC). The MMC is fabricated by liquid-melt stir casting process and then solution heat treated (T6). The hardness and tensile strength of the solution heat-treated samples are 138.7 BHN and 472.66 MPa, respectively. Central composite design of response surface methodology (RSM) is used to design the experiment and is performed to investigate the effects of process parameters such as pulse width, time between pulses, servo control mean reference voltage, short pulse time, wire feed rate and wire mechanical tension on performance measures such as surface roughness and cutting velocity (CV). Mathematical models are developed to predict the results for performance characteristics well in advance. Desirability function approach is used to find the optimal parametric combination for single-objective optimization as well as for multi-objective optimization. The CV 8.1235 mm/min. and surface roughness 1.2549 μm indicate that the developed MMC can be successfully machined by wire EDM. Additivity test and confirmation test are performed to validate the mathematical model and to confirm the optimal parametric combinations developed by RSM, respectively. Mechanical properties investigation and successful machining indicate that this material can be used in the aerospace industries. [ABSTRACT FROM AUTHOR]

Background. This study aimed to evaluate and compare total cost of sevoflurane and propofol for 1.0 MAC-hour of anaesthesia, employing three anaesthetic techniques. Methods. Adult patients scheduled for surgical procedures under general anaesthesia anticipated to last approximately an hour were randomized into three groups (n = 15 each), to receive anaesthesia using one of the following techniques: low flow technique involving induction with propofol, followed by sevoflurane delivered using initial fresh gas flows of 6 L/min tillMAC reached 1.0 and then reduced to 0.5 L/min; alternatemethod of low flow entailing only a difference in fresh gas flow rates beingmaintained at 1 L/min throughout; the third technique involving use of sevoflurane for both induction and maintenance of anaesthesia. Results. Cost of sevoflurane to maintain 1 MAC-hour of anaesthesia was clinically least with low flow anaesthesia, though statistically similar amongst the three techniques. Once the cost of propofol used for induction in two of the three groups was added to that of sevoflurane, cost incurred was least with the technique using sevoflurane both for induction and maintenance of anaesthesia, as compared to low flow and alternative low flow techniques, a 26% and 32% cost saving, respectively (P < 0.05). [ABSTRACT FROM AUTHOR]

This paper presents the fabrication process of Al/ZrO 2(p)-metal matrix composite (MMC) by liquid stir casting technique. The paper also presents an experimental investigation of the machining characteristics and the effect of wire electrical discharge machining (WEDM) process parameters during machining of newly developed Al/ZrO 2(p) MMC. Experiments have been carried out to investigate the effects of input parameters such as dielectric conductivity, pulse width, pulse off time, maximum feed rate, servo control mean reference voltage, pulse on time, wire feed rate, wire mechanical tension and dielectric injection pressure on performance measures like spark gap and material removal rate. The optimal setting of parameters has been determined through experiments planned, conducted and analyzed using Taguchi method. L 36-mixed orthogonal array (2 1 × 3 8) has been selected to design the experiments. The significant process parameters have also been identified and their effects on performance measures have been studied in detail. The results obtained have been validated by conducting the confirmation experiments. Yield strength of the fabricated MMC has been found to be 88.3 MPa. The newly developed MMC can be machined effectively by WEDM and can be used in aerospace industries. [ABSTRACT FROM AUTHOR]

Background: Leprosy is an ideal human disease to study T cell regulation as patients show correlation between cytokine skewed Th1-Th2 responses and clinical forms of the disease. The Role of transcription factors on the modulation of Th1 and Th2 responses by M. leprae antigens has not been adequately studied. In the present study, we studied the effect of M. leprae antigens on transcription factors STAT-4, STAT-6 and CREB and their correlation with Th1/Th2 cell mediated immune responses in leprosy.Methods: Leprosy patients of both categories of tuberculoid leprosy (BT/TT) and lepromatous leprosy (BL/LL) were selected from the OPD of NJ1L & OMD, (ICMR), Agra and healthy individuals (H) were chosen from the staff and students working in the institute. Peripheral blood mononuclear cells (PBMCs) of the study subjects were stimulated with M. leprae antigens (WCL, MLSA, and PGL-1). Sandwich ELISA was done in the culture supernatants of healthy and leprosy patients to detect IL-4, IL-10 and IFN-γ. Further, expression of IFN-γ and IL-4 and activation of STAT4, STAT6 and CREB transcription factors in CD4+ T cell with or without stimulation of M. leprae antigens was investigated by flow cytometry.Results: Lepromatous leprosy patients showed significantly lower IFN-γ and higher IL-4 levels in culture supernatant and significantly low expression of IFN-γ and higher expression of IL-4 by CD4+ T cells than healthy individuals with or without antigenic stimulation. Antigenic stimulation significantly increased IL-10 in BL/LL patients but not in BT/TT patients or healthy individuals. PGL-1 stimulation led to significantly higher activation of STAT-6 in BT/TT and BL/LL patients in comparison to healthy individuals. All the three antigens led to activation of CREB in healthy and BT/TT patients but not in BL/LL patients.Conclusion: Our findings show that M. leprae antigens differentially modulate activation of T cell transcription factors STAT-4/STAT-6 and CREB. These transcription factors are well known to regulate Th1 and Th2 mediated immune response which in turn could play vital role in the clinical manifestations of leprosy. These observations may help to determine how these T cell transcription factors affect the development of immune dysfunction and whether these new pathways have a role in immunomodulation in intracellular diseases like leprosy and TB. [ABSTRACT FROM AUTHOR]