Wear resistance evaluation of cryogenically treated AISI–H11 steel: An optimization approach

112-125The consequences of key process parameters of cryogenic treatment (i.e. holding time and temperature) on the average coefficient of friction and wear rate in dry sliding condition at different level of load (60, 80, 100, 120 & 140 N) and sliding velocity (0.628, 0.942, 1.257, 1.571 & 1.885 m/s) have been explored through cubic regression mathematical modeling technique. An average error of 1% and 9.9% has been observed in the experimental and model given values for coefficient of friction and wear rate. Mathematical model equation capability is within the range of 95% confidence level. Moreover, desirability function approach has been employed to find out the process parameter to have lower wear resistance. Worn out samples have been examined with field emission scanning electron microscope (FESEM) and reveals that the operative mechanism for wear is delaminating and rupturing of matrix

Optimization of friction and wear characteristics of varied cryogenically treated hot die steel grade AISI-H13 under dry condition

Abstract Cryogenic treatment (CT) is a relatively new field, which has emerged during the last three decades of the twentieth century. However, its impact on material shaping and making tool life, and enhancement of their mechanical properties are quite remarkable. The selection of appropriate process parameters for CT is essential for cost reduction and optimum productivity. This study focuses on the influence of key parameters of CT cycles (i.e., soaking temperature and duration) on the friction and wear behavior of AISI H13 hot die steel under dry sliding conditions against hardened and tempered AISI D3 cold work tool steel (counter face) at varying sliding speeds and loads. Mathematical models have been developed for wear rate, the average coefficient of friction, and maximum contact temperature using the Box-Cox methodology. The developed mathematical models have been validated by comparing with the experimental results. Moreover, the optimum values of the process parameter have been employed to maximize the output and validate the same by confirmation of the experiments. To the best of our knowledge, this is the first study that demonstrates the modeling and optimization of sliding friction and wear characteristics of AISI H13 under varied CT cycles

Anesthetic management of primary hyperparathyroidism: A role rarely noticed and appreciated so far

Endocrine surgeries have been on the rise for the last few years. During surgery, endocrine disorders present unique challenges to the endocrinologist and to the attending anesthesiologist. The endocrine, electrolyte and metabolic disturbances resulting from such disorders can have a profound effect on the normal human physiological milieu. Surgery of parathyroid glands is no exception and is associated with a multiple challenges during pre-, intra-, and post-operative period. Pre-op examination and optimization is essential so as to prevent any intra-op or post-op complications. The most striking electrolyte disturbance during parathyroid surgery is the imbalance of calcium levels in the body and the main emphasis during the entire peri-operative period revolves around the maintenance of normal serum calcium levels. The present article review in depth the various anesthetic considerations and implications during parathyroid surgery with an emphasis on pre-op preparation for elective and emergency surgery

Improvement of tribological behavior of H-13 steel by optimizing the cryogenic-treatment process using evolutionary algorithms

The effect of soaking temperature and duration of cryogenic treatment cycles were investigated for the hot die steel AISI-H13 to improve its wear resistance. The amount of wear, average friction coefficient, and maximum local contact temperature were investigated against the AISI D3 cold work tool steel (hardened and tempered) used as counter-surface for five conditions – varying the loading and sliding speed. Sliding parameter has great influence over wear rate when is compared to load effects. The wear detected on the surface analyzed is adhesive wear produced by deformation lips, surface cracks and fractured ridges. To achieve an increase of efficiency, Particle Swarm Optimization is preferred as it showed lower deviation than Bacteria Foraging Optimization in optimized results

A REVIEW ON NANOSPONGES A REVIEW ON NANOSPONGES: A BOON TO TARGETED DRUG DELIVERY FOR ANTICANCER DRUG

In recent decades, the rise in the investigation of new drugs had made health-care system expensive compared to conventional drug delivery systems and techniques. The present drug delivery systems have become highly productive and are growing fast. Majority of the anticancer agent has low water solubility resulting in multistep synthetic routes that require higher selectivity and specificity that can cause difficulty in the development of the formulation. Nanosponges (NSs) are branched cyclodextrin (CD) polymeric systems which have proven to be a boon in the pharmaceutical and biomedical fields. Different kinds of NSs based on different types of CDs and crosslinkers are used for developing of new drug formulations from the past few years for various applications in health care. Nanotechnology has overcome the issues regarding the drug solubility, stability, and other parameters and has attained success in achieving of sustained release, increased activity, improved permeability, delivery of nucleoprotein, the stimuli-responsive release of the drug, and improved drug bioavailability. There is a huge eruption of research on NSs for cancer treatment. Multiple anticancer moieties have been developed, taking into account the pharmacological and physicochemical perspective of the drug to develop a NS formulation. Our target in this review is to catch an efficient and far-reaching NSs for malignancy cancer treatment announced until now. This survey will give a perfect stage for providing details for researchers taking a shot at using new polymers for improving the treatment of the disease using nanotechnology. The present article provides details regarding antineoplastic molecules and provides ideas on CD-based NSs specifically using curcumin, tamoxifen, resveratrol, quercetin, oxygen-NSs, temozolomide, doxorubicin, and 5-fluorouracil (5-FU), and erlotinib (ETB) glutathione

Challenging aspects of and solutions to diagnosis, prevention, and management of hypoglycemia in critically ill geriatric patients

There is a worldwide pandemic of diabetes. Also there is a gradual and steady increase in the elderly population. Often clinicians are faced with managing dysglycemia in the elderly with underlying sepsis and multiple comorbidities. This predisposes the elderly to potentially increased chances of hypoglycemia in inpatient settings. This article reviews the altered renal physiology and its effects in the management of dysglycemia in the elderly population. It also emphasizes the role of renal insufficiency and sepsis as the main etiological factors for hypoglycemia in both diabetics and nondiabetics in the inpatient settings

Management of diabetes in the elderly with canagliflozin: A newer hypoglycemic drug on the horizon.

Canagliflozin is the first available oral inhibitor of sodium/glucose cotransporter 2 (SGLT2) in the market. At the outset it sounds excellent for the use in the elderly diabetic population, because of its minimal tendency to cause hypoglycemia. However, the clinician needs to exercise caution as it needs to be dosed renally. The clinician needs to be circumspect about potential drug interactions, especially when there is an underlying chronic kidney disease (CKD) and congestive heart failure (CHF). Also its use is best avoided in people who are predisposed to genital mycotic and urinary tract infections (UTI)

Polypharmacy and potentially inappropriate medication use as the precipitating factor in readmissions to the hospital

Background and Aim: Readmission to the hospital within 30 days of discharge from the hospital is a common occurrence. Congestive heart failure is the most common cause of readmissions in the hospital. We hypothesized that irrespective of the admission diagnosis polypharmacy and potentially inappropriate use of medications (PIM) leads to readmissions within 30 days of discharge from the hospital. Materials and Methods: A retrospective study was carried out by reviewing the hospital records of 414 patients who were readmitted to the hospital within 30 days of discharge from the hospital between January 2008 and December 2009. The data was stratified to see which patients were on polypharmacy and/or on PIM. Polypharmacy was defined as use of more than 5 medications. PIM was defined as per the modified Beers criteria. Day 0 was defined as the day of discharge and day1 was defined as the day-after Admission to the hospital. Statistical analysis was carried out using a two-way analysis of variance (ANOVA) on the data to see if polypharmacy and/or PIM was related to readmission within 30 days of discharge irrespective of admission diagnosis. Results: Polypharmacy was related to hospital readmission at day 1 and day 0, however inappropriate drug use was found to be not related at any day. Polypharmacy and PIM combined had a positive correlation to readmission only on days 1 and 0 and it was statistically significant. The use of minimal and appropriate use of drugs was statistically significant compared to polypharmacy and PIM use. Conclusions: Polypharmacy and PIM are under recognized cause of readmissions to the hospital

Clinical and critical care concerns in severely ill obese patient

The incidence of obesity has acquired an epidemic proportion throughout the globe. As a result, increasing number of obese patients is being presented to critical care units for various indications. The attending intensivist has to face numerous challenges during management of such patients. Almost all the organ systems are affected by the impact of obesity either directly or indirectly. The degree of obesity and its prolong duration are the main factors which determine the harmful effect of obesity on human body. The present article reviews few of the important clinical and critical care concerns in critically ill obese patients