Effect of Phosphine on Coke Formation during Steam Cracking of Propane.

In conventional steam cracking feedstocks, contaminants such as sulfur, phosphine, and heavy metal components, present in trace levels, are believed to affect coke formation on high temperature alloys. To gain an understanding of the role of phosphine coking rates on 25/35, CrNi and Al-containing reactor materials were determined in a plug flow reactor during cracking of a propane feedstock doped with ppb levels of PH3 in the presence of DMDS. The presence of phosphine decreased the asymptotic coking rates by more than 20%, while it had a smaller influence on the catalytic coking rate. The coking rate was more severely reduced for the 25/35 CrNi alloy in comparison to the Al-containing alloy. The ppm levels of phosphine did not affect the olefin yields nor the production of undesired carbon monoxide. The morphology of the coked alloys were studied using an off-line Scanning Electron Microscope with Energy Dispersive X-ray detector (SEM with EDX) images of coked coupons. Two types of coke morphology are observed, i.e., filamentous coke with DMDS as an additive and globular coke in the presence of phosphine. The effect of phosphine on the material has a positive impact on the oxide scale homogeneity of 25/35 CrNi alloy, whereas the Al-containing alloy remained unchanged.

Sociodemographic and Clinical Profiles of Patients with Irritable Bowel Syndrome: A Cross-sectional, Multi-centric, Epidemiological Study in India.

AIMS: Irritable bowel syndrome (IBS) is a functional gastrointestinal disorder characterized by impaired gut-brain interaction. Considering the paucity of evidence in the Indian setting, the current study was conducted to determine the sociodemographics, clinical profiles, management practices, and patients' perception among newly diagnosed patients with IBS. METHODS: This was a cross-sectional, single-visit, observational, non-interventional, epidemiological study conducted across 12 centres. The primary objective was evaluation of sociodemographic and clinical profiles. The key secondary objective was assessment of gastrointestinal symptom severity including evaluation of anxiety and depression using the hospital anxiety and depression scale (HADS) scores. Knowledge, attitude, and practices (KAP) were evaluated as an exploratory objective. RESULTS: Out of 300 enrolled patients, 120 (40%) were aged 31-45 years (mean age: 38.55±12.45 years), and 204 were men (68%). Overall, 40% of patients belonged to the upper-middle-class, with a Kuppuswamy score of 16-25. Most patients (91%) did not work in night shifts. Only 13% of patients performed more than recommended physical activity. Stress and food were the leading triggers for IBS (29%). Abdominal pain and diarrhoea as cardinal symptoms were reported by 43.3% and 33.0% patients, respectively. Borderline abnormal anxiety and depression were reported by 21.3% and 26.7% of patients, respectively. KAP assessment revealed that 56.0% of patients had poor knowledge, 26.3% had moderate knowledge, and 17.7% had good knowledge about IBS; nevertheless, 43% of patients maintained high levels of precaution towards managing symptoms. CONCLUSION: Given the limited knowledge about IBS in India among newly diagnosed patients, strategies to enhance awareness about the condition are warranted.

Exploring the convergence of knowledge, attitudes, and practice towards mental illness among nurses in South India: A cross-sectional analysis.

Mental illness is a leading cause of global morbidity. Over 10% of the Indian population experience a mental health disorder yet deficits in knowledge and negative attitudes towards metal illness limit early identification and treatment. We explored the relationship among knowledge, attitudes and practice among generalist nurses working at a large tertiary care hospital in South India. Participants demonstrated positive attitudes and sufficient knowledge about mental illness, yet these variables did not predict practice when presented with a patient case scenario of postpartum depression-related mental distress in a non-psychiatric inpatient setting. Findings warrant application-based pedagogies to facilitate nurses' enhanced recognition and treatment of patients experiencing mental distress in non-psychiatric settings.

Effect of Long-Term High Temperature Oxidation on the Coking Behavior of Ni-Cr Superalloys.

The service time of an industrial cracker is strongly dependent on the long-term coking behavior and microstructure stability of the reactor coil alloy. Super alloys are known to withstand temperatures up to even 1400 K. In this work, several commercially available alloys have been first exposed to a long term oxidation at 1423 K for 500 h, so-called metallurgic aging. Subsequently, their coking behavior was evaluated in situ in a thermogravimetric setup under ethane steam cracking conditions (Tgasphase = 1173 K, Ptot = 0.1 MPa, XC2H6 = 70%, continuous addition of 41 ppmw S/HC of DMDS, dilution δ = 0.33 kgH2O/kgHC) and compared with their unaged coking behavior. The tested samples were also examined using scanning electron microscopy and energy diffractive X-ray for surface and cross-section analysis. The alloys characterized by increased Cr-Ni content or the addition of Al showed improved stability against bulk oxidation and anti-coking behavior after application of metallurgic aging due to the formation of more stable oxides on the top surface.

Comparison of Macintosh laryngoscope and C-MAC video laryngoscope for intubation in lateral position.

BACKGROUND AND AIMS: Endotracheal intubation is conventionally performed when the patient is in supine position. It may be required to secure airway in laterally positioned patient. Tracheal intubation in lateral position seems to be difficult because the laryngeal view is compromised. Hence, C-MAC video laryngoscope (Karl Storz, Germany), a newer device using a modified macintosh blade may be useful for intubation in lateral position. MATERIAL AND METHODS: A total of 100 American Society of Anesthesiologists Grade I and II patients, randomly allotted to C-MAC or direct laryngoscopy group. Patients with difficult airway were excluded. After induction of anesthesia, patient was put in right-lateral position and intubation was carried out by consultant who is well-versed in using C-MAC laryngoscope. Time for intubation, number of attempts, Modified Cormack - Lehane grade, mucosal injury, and external laryngeal manipulation applied were noted. STATISTICAL ANALYSIS: Demographics and baseline airway assessments were analyzed using summary statistics. Unpaired t-test was used to assess intubation time. Number of attempts, esophageal intubation, dental injury, mucosal injury, use of stylet, and application of external laryngeal manipulation were analyzed using Chi-square test. RESULTS: Overall intubation success rate was 100%. The time taken in C-MAC group was 24.8 ± 8.5 s and in direct group was 33.8 ± 9.12 s. The number of intubation attempts was not significant. Cormack - Lehane grade was better with C-MAC laryngoscope. Mucosal injury and use of external laryngeal manipulation was more in direct group. CONCLUSION: C-MAC is better than Macintosh laryngoscope for intubation in lateral position.

Fiberoptic intubation through laryngeal mask airway for management of difficult airway in a child with Klippel-Feil syndrome.

The ideal airway management modality in pediatric patients with syndromes like Klippel-Feil syndrome is a great challenge and is technically difficult for an anesthesiologist. Half of the patients present with the classic triad of short neck, low hairline, and fusion of cervical vertebra. Numerous associated anomalies like scoliosis or kyphosis, cleft palate, respiratory problems, deafness, genitourinary abnormalities, Sprengel's deformity (wherein the scapulae ride high on the back), synkinesia, cervical ribs, and congenital heart diseases may further add to the difficulty. Fiberoptic bronchoscopy alone can be technically difficult and patient cooperation also becomes very important, which is difficult in pediatric patients. Fiberoptic bronchoscopy with the aid of supraglottic airway devices is a viable alternative in the management of difficult airway in children. We report a case of Klippel-Feil syndrome in an 18-month-old girl posted for cleft palate surgery. Imaging of spine revealed complete fusion of the cervical vertebrae with hypoplastic C3 and C6 vertebrae and thoracic kyphosis. We successfully managed airway in this patient by fiberoptic intubation through classic laryngeal mask airway (LMA). After intubation, we used second smaller endotracheal tube (ETT) to stabilize and elongate the first ETT while removing the LMA.

Novel method to differentiate 3T3 L1 cells in vitro to produce highly sensitive adipocytes for a GLUT4 mediated glucose uptake using fluorescent glucose analog.

Adipocytes play a vital role in glucose metabolism. 3T3 L1 pre adipocytes after differentiation to adipocytes serve as excellent in vitro models and are useful tools in understanding the glucose metabolism. The traditional approaches adopted in pre adipocyte differentiation are lengthy exercises involving the usage of IBMX and Dexamethasone. Any effort to shorten the time of differentiation and quality expression of functional differentiation in 3T3 L1 cells in terms of enhanced Insulin sensitivity has an advantage in the drug discovery process. Thus, there is a need to develop a new effective method of differentiating the pre adipocytes to adipocytes and to use such methods for developing efficacious therapeutic molecules. We observed that a combination of Dexamethasone and Troglitazone generated differentiated adipocytes over fewer days as compared to the combination of IBMX and Dexamethasone which constitutes the standard protocol followed in our laboratory. The experiments conducted to compare the quality of differentiation yielded by various differentiating agents indicated that the lipid droplet accumulation increased by 112 % and the GLUT4 mediated glucose uptake by 137 % in cells differentiated with Troglitazone and Dexamethasone than in cells differentiated traditionally. The comparative studies conducted for evaluating efficient measurable glucose uptake by GOPOD assay, radioactive (3)H-2-deoxy-D-glucose assay and by non-radioactive 6-NBDG (fluorescent analog of glucose) indicated that the non-radioactive method using 6-NBDG showed a higher signal to noise ratio than the conventional indirect glucose uptake method (GOPOD assay) and the radioactive (3)H-2-deoxy-D-glucose uptake method. Differentiated 3T3 L1 cells when triggered with 2.5 ng/mL of Insulin showed 3.3 fold more glucose uptake in non-radioactive method over the radioactive (3)H-2-deoxy-D-glucose uptake method. The results of this study have suggested that a combination of Dexamethasone and Troglitazone for 3T3 L1 cell differentiation helps in better quality differentiation over a short period of time with increased sensitivity to Insulin. The application of these findings for developing new methods of screening novel Insulin mimetics and for evaluating the immunological responses has been discussed.

Combined spinal epidural anesthesia for laparoscopic appendectomy in adults: A case series.

BACKGROUND: Laparoscopy is one of the most common surgical procedures and is the procedure of choice for most of the elective abdominal surgeries performed preferably under endotracheal general anesthesia. Technical advances in the field of laparoscopy have helped to reduce surgical trauma and discomfort, reduce anesthetic requirement resulting in shortened hospital stay. Recently, regional anaesthetic techniques have been found beneficial, especially in patients at a high risk to receive general anesthesia. Herewith we present a case series of laparoscopic appendectomy in eight American Society of Anaesthesiologists (ASA) I and II patients performed under spinal-epidural anaesthesia. METHODS: Eight ASA Grade I and II adult patients undergoing elective Laparoscopic appendectomy received Combined Spinal Epidural Anaesthesia. Spinal Anaesthesia was performed at L(2)-L(3) interspace using 2 ml of 0.5% (10 mg) hyperbaric Bupivacaine mixed with 0.5ml (25 micrograms) of Fentanyl. Epidural catheter was inserted at T(10)-T(11) interspace for inadequate spinal anaesthesia and postoperative pain relief. Perioperative events and operative difficulty were studied. Systemic drugs were administered if patients complained of shoulder pain, abdominal discomfort, nausea or hypotension. RESULTS: Spinal anaesthesia was adequate for surgery with no operative difficulty in all the patients. Intraoperatively, two patients experienced right shoulder pain and received Fentanyl, one patient was given Midazolam for anxiety and two were given Ephedrine for hypotension. The postoperative period was uneventful. CONCLUSION: Spinal anaesthesia with Hyperbaric Bupivacaine and Fentanyl is adequate and safe for elective laparoscopic appendectomy in healthy patients but careful evaluation of the method is needed particularly in compromised cardio respiratory conditions.

Traumatic fracture of posterior chamber intraocular lens.

An 18-year-old man developed a fracture in a single-piece polymethylmethacrylate posterior chamber (PC) intraocular lens (IOL) at the optic-haptic junction with dislocation of the IOL into the anterior chamber after a fist injury to the eye. The dislocated IOL was explanted and replaced with another PC IOL.