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In the present study, Stainless steel 316L (SS316L) cylindrical specimens were fabricated at two different build orientations and two different laser powers using Laser powder bed fusion process (LPBF). Microstructural characterization such as XRD, SEM, EBSD analysis and tensile testing were carried out on fabricated specimens in stress relieved condition to understand the anisotropic behavior of LPBF printed specimens. Horizontally oriented specimens showed higher tensile strength when compared to vertically oriented specimens for both laser powers. XRD and EBSD phase maps did not reveal the presence of any secondary phases. However, build orientation and laser power affected the crystallite size of the samples. Bimodal grain structure comprising coarse columnar grains and fine equiaxed grains were observed from the micrographs. With variation in build orientation, there was a significant change in the average grain size of the specimens. High dislocation density was observed in horizontally oriented samples built at low laser power because of dislocation annihilation that can occur at high temperatures. However, EBSD analysis revealed random weak crystallographic texture which does not vary significantly with laser power or build orientation. Variation in grain size, grain morphology, sub-grain features and dislocation density are the reasons for the anisotropic tensile behavior observed in LPBF printed SS316L coupons in stress relieved condition. [ABSTRACT FROM AUTHOR]

Purpose: To study the effect of rosuvastatin 40 mg (initiated 7 days prior to surgery) in patients undergoing valve replacement (VR) for rheumatic mitral valve disease on left ventricular (LV) strain and biomarker release kinetics. Methods: In this randomized study, cardiac biomarkers viz. troponin I (TnI), Creatine kinase MB (CK-MB), N-terminal pro B-type natriuretic peptide (NTPBNP) were measured before surgery; and 8, 24 and 48 h postoperatively. Global LV (circumferential, global circumferential strain (GCS); longitudinal, GLS; radial, global radial strain (GRS)) strains were measured preoperatively; and 48 h and 30 days postoperatively. Results: Following VR, Global Longitudinal Strain (GLS), Global Circumferential Strain (GCS) and Global Radial Strain (GRS) declined at 48 h in both statin loaded (SL) and non loaded (NL) groups. The %decline in strain was significantly lower in SL group (% change in GLS 35.8% vs 38.8%, GCS 34% vs 44.1%, GRS 45.7% vs 52.6%; p < 0.001). All strain values improved at 30 days with higher improvement in SL group (GLS -15.92 ± 2.00% vs -12.6 ± 1.66%, GCS -15.12 ± 2.93% vs -13.04 ± 2.44%; GRS 22.12 ± 6.85% vs 19.32 ± 6.48%). While TnI, CKMB, NTPBNP increased following surgery, values at 8, 24 and 48 h were lower in the SL vs. NL group. Mean change (baseline to peak biomarker value) was also significantly lower in SL group. The SL group had shorter hospital and Intensive Care Unit (ICU) stay. On Receiver Operating Characteristic Curve (ROC) analysis, baseline GCS ≤ 14% best predicted postoperative 30 day Left Ventricular Ejection Fraction (LVEF) ≤ 50%. Conclusion: Pre-operative high dose rosuvastatin was "cardioprotective" with favorable effect on LV global strain and release kinetics of biomarkers. These cut-offs (described for the first time for rheumatic VR) can be used as prognostic predictors. [ABSTRACT FROM AUTHOR]

The use of focused assessment with sonography for trauma (FAST) examination in pediatric blunt abdominal trauma (BAT) has not been well accepted because of its poor sensitivity. We aim to determine whether the FAST combined with elevated liver enzymes, i.e., aspartate transaminase (AST), could be used as a better screening tool for intra-abdominal injury (IAI) in pediatric BAT and develop a new prediction model. A case series analysis was performed among pediatric patients (age < 18 years) with BAT, presenting to a level-1 trauma center. Data on patient demographics, vital signs, mechanism of injury, FAST finding, contrast-enhanced computed tomography (CECT) scan of the abdomen, and serum AST levels, were collected. Multiple logistic regression (MLR) was used to develop a prediction model for IAI. Overall, 499 children were identified. FAST was positive in 72 patients, whereas 69 patients had IAI in a CECT. FAST alone had a sensitivity of 76.8%. FAST examination's negative predictive value (NPV) and negative likelihood ratio (NLR) were 95.8% and 0.24, respectively. Combining FAST and AST levels led to an increase in sensitivity to 91.3%, NPV to 97.9%. The NLR decreased to 0.1, which was clinically more relevant. In the MLR model, the odds ratios for the presence of IAI were significant for FAST and AST levels. Hence, FAST and AST levels were included in the new 'F-AST score'. A score of one was assigned for FAST positive and zero for FAST negative. AST level < 90 U/L was assigned a score of zero and > 90 U/L as one. Aggregate F-AST score ranged from 0 to 2. The receiver's operating characteristics (ROC) analysis showed the F-AST score to be very accurate with an area under the ROC curve of 0.905. Pediatric patients with a F-AST score of 0 (negative FAST and AST < 90 U/L) may be observed rather than subjected to CT scan radiation risk. [ABSTRACT FROM AUTHOR]

Conventionally, routes of vascular access commonly include femoral and radial arteries with brachial, ulnar and subclavian arteries being rarely used for coronary interventions. Non-femoral arterial access is being increasingly preferred to minimise groin puncture site complications, prolonged immobilization and duration of hospital stay. However, radial artery cannulation is also fraught with fears of tortuosity, loops, vascular spasm, perforation, pseudoaneurysm formation, arm hematoma and arterial occlusion. In contemporary practice when most of the coronary procedures are being done via transradial access, encountering one of the above-mentioned hurdles often forces the operator to switchover to femoral access. Here, we explore the rationale, feasibility, operational logistics, clinical implications and future directions for using simultaneous radio-ulnar arterial access in the same extremity. [ABSTRACT FROM AUTHOR]