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Abstract: In this paper, we report results obtained from laser assisted three-dimensional (3-D) atom probe tomography (APT) on wüstite (Fe1−x O). Oxides are generally insulating and hence hard to analyse in conventional electrical assisted APT. To overcome this problem, femtosecond laser pulses are used instead of voltage pulses. Here we discuss some aspects of pulsed laser field evaporation and optimization of parameters to achieve better chemical accuracy. [Copyright &y& Elsevier]

Bilateral congenital mid ureteric stenosis is a very rare entity causing hydroureteronephrosis. The pathophysiology and aetiology of this condition is uncertain. Congenital functional obstruction of the mid ureter has only 17 reported cases, that too of unilateral pathology. We report a case of an 11-year-old male child who was presented with left sided lump in abdomen since one year. On bilateral retrograde ureteropyelography (RGP), bilateral mid ureteric stenosis was documented at the level of pelvic brim. Tc99m Diethylene Triamine Pentacaetic Acid (DTPA) scan showed non functioning left kidney and decreased function and retention on right side. We did a left nephroureterectomy and uretero-ureterostomy without tapering over a Double-J stent (DJ), with excision of stenosed segment on right side. Pathological review of the ureteric segments of both sides revealed proximal dilatation with non-specific thickening of the muscular wall of the stenosed segments of ureter. The differential diagnosis must additionally include ureteral valves and fibro epithelial polyps. Important role of intravenous pyelography in such cases must be emphasized to localize the pathology site. In addition, retrograde ureteropyelography is essential in management of this anomaly to delineate the stenosed segment of the ureter preoperatively, so that the surgeon can be well prepared with final plan of management.

Austenitic stainless steel D9 is a candidate for Generation IV nuclear reactor structural materials due to its enhanced irradiation tolerance and high-temperature creep strength compared to conventional 300-series stainless steels. But, like other austenitic steels, D9 is susceptible to irradiation-induced clustering of Ni and Si, the mechanism for which is not well understood. This study utilizes atom probe tomography (APT) to characterize the chemistry and morphology of Ni-Si nanoclusters in D9 following neutron or proton irradiation to doses ranging from 5-9 displacements per atom (dpa) and temperatures ranging from 430-683 °C. Nanoclusters form only after neutron irradiation and exhibit classical coarsening with increasing dose and temperature. The nanoclusters have Ni 3 Si stoichiometry in a Ni core-Si shell structure. This core-shell structure provides insight into a potentially unique nucleation and growth mechanism-nanocluster cores may nucleate through local, spinodal-like compositional fluctuations in Ni, with subsequent growth driven by rapid Si diffusion. This study underscores how APT can shed light on an unusual irradiation-induced nanocluster nucleation mechanism active in the ubiquitous class of austenitic stainless steels.

Soft X-ray spectromicroscopy at the O K-edge, U N 4,5 -edges and Ce M 4,5 -edges has been performed on focused ion beam sections of spent nuclear fuel for the first time, yielding chemical information on the sub-micrometer scale. To analyze these data, a modification to non-negative matrix factorization (NMF) was developed, in which the data are no longer required to be non-negative, but the non-negativity of the spectral components and fit coefficients is largely preserved. The modified NMF method was utilized at the O K-edge to distinguish between two components, one present in the bulk of the sample similar to UO 2 and one present at the interface of the sample which is a hyperstoichiometric UO 2+x species. The species maps are consistent with a model of a thin layer of UO 2+x over the entire sample, which is likely explained by oxidation after focused ion beam (FIB) sectioning. In addition to the uranium oxide bulk of the sample, Ce measurements were also performed to investigate the oxidation state of that fission product, which is the subject of considerable interest. Analysis of the Ce spectra shows that Ce is in a predominantly trivalent state, with a possible contribution from tetravalent Ce. Atom probe analysis was performed to provide confirmation of the presence and localization of Ce in the spent fuel., (open access.)

Atom probe tomography (APT), a 3D microscopy technique, has great potential to reveal atomic scale compositional variations, such as those associated with irradiation damage. However, obtaining accurate compositional quantification by APT for high bandgap materials is a longstanding challenge, given the sensitivity to field evaporation parameters and inconsistent behaviors across different oxides. This study investigates the influence of APT laser energy and specimen base temperature on compositional accuracy in single crystal thoria (ThO 2 ). ThO 2 has a broad range of applications, including advanced nuclear fuels, sensors, lasers and scintillators, electrodes, catalysis, and photonics and optoelectronics. The expected stoichiometry of ThO 2 is achieved at APT base temperature of 24 K and laser energy of 100 pJ. To overcome mass resolution limitations associated with significant thermal tails, Bayesian methods are applied to deconvolute ion identity within the mass spectra. This approach affirms that the parameters chosen are appropriate for APT analysis of ThO 2 ., (Copyright © 2020. Published by Elsevier B.V.)

Introduction: Majority of burn injuries occur in developing world. There have been many advances in burn care management. But this advance comes at a price of ever increasing burn sequel of scarring. Burn scar contractures, in spite of being preventable, continue to be a common reality in our world. This paper aims to evaluate the lacunae in burn care leading to formation of contractures, to evaluate common sites of contractures, practice of advising splintage and anti-deformity positioning., Procedure: This retrospective observational study was conducted over a period of six years (January 2010-December 2015) at a tertiary Burn unit in Mumbai (India). The records of burn contracture patients were scrutinized to obtain the data regarding patient's socio-demographic profile, details of burn injury, splinting and exercises advised and details of surgeries required. Data was tabulated and analysed., Results: There was a significantly lower prevalence of advice regarding splinting, mobilization exercises and pressure garments. The prevalence of early surgery was also found to be low., Conclusions: Attempt has been made to identify the factors affecting the prevalence of burn scar contractures. Authors recommend that efforts be made for improving the knowledge of the treating doctors. Also, efforts should be made to increase awareness of burn prevention and emergent management., (Copyright © 2019 Elsevier Ltd and ISBI. All rights reserved.)

Background: Wounds have since long, contributed majorly to the health-care burden. Infected long-standing non-healing wounds place many demands on the treating surgeon and are devastating for the patients physically, nutritionally, vocationally, financially, psychologically and socially. Acetic acid has long been included among agents used in the treatment of infected wounds. In this study, we have evaluated the use of acetic acid for topical application in the treatment of infected wounds., Materials and Methods: A total of 100 patients with infected wounds were treated with topical application of 1% acetic acid as dressing material after appropriate cleaning. A specimen of wound swab was collected before first application and further on days 3, 7, 10 and 14. Daily dressings of wounds were done similarly. Minimum inhibitory concentration (MIC) of acetic acid against various organisms isolated was determined., Results: The patients treated ranged between 9 and 60 years, with the mean age 33 years. Nearly 70% of patients were male. Aetiologies of wounds: infective 35, diabetic 25, trauma 20, burns 10, venous ulcers 5 and infected graft donor site 5. Various microorganisms isolated include Pseudomonas aeruginosa (40%), Staphylococcus aureus (2%), Acinetobacter (12%), Escherichia Coli (5%), Proteus mirabilis (3%), Klebsiella (18%), methicillin-resistant S. aureus (10%), Streptococcus (2%) and Enterococcus (1%), Citrobacter (1%). Few wounds (6%) also isolated fungi. About 28%, 64% and 8% of patients isolated no growth on culture after 7, 14 and 21 days, respectively. MIC of all isolated organisms was ≤0.5%., Conclusion: pH of the wound environment plays a pivotal role in wound healing. Acetic acid with concentration of 1% has shown to be efficacious against wide range of bacteria as well as fungi, simultaneously accelerating wound healing. Acetic acid is non-toxic, inexpensive, easily available and efficient topical agent for effective elimination of wound infections caused due to multi-drug resistant, large variety of bacteria and fungus., Competing Interests: There are no conflicts of interest.

The transfer of autologous fat has been performed since the 1890s; however, its popularity has increased owing to better understanding of fat harvesting and processing techniques. In this article, fat grafting procedure has been used to correct posttraumatic facial deformities in 25 cases. As healing of grafted fat is unpredictable, we have used longer follow-up of 2 years. Evaluation was performed using facial photographs and MRI scans. Scientific literature describes an absorption rate ranging from 20 to 90%. High fat graft resorption rates have been attributed to traumatic handling of the graft during harvest, processing, and injection. Various processing techniques have been suggested. The goal of these techniques is to obtain greater adipocyte cell survival and, consequently, more reliable clinical results. In our study, we have used syringe aspiration and low-speed centrifuge for processing of fat which has resulted in good clinical outcomes.

Background: Indian noses are broader and lack projection as compared to other populations, hence very often need augmentation, that too by large volume. Costal cartilage remains the material of choice in large volume augmentations and repair of complex primary and secondary nasal deformities. One major disadvantage of costal cartilage grafts (CCG) which offsets all other advantages is the tendency to warp and become distorted over a period of time. We propose a simple technique to overcome this menace of warping., Materials and Methods: We present the data of 51 patients of rhinoplasty done using CCG with counterbalancing technique over a period of 4 years., Results: No evidence of warping was found in any patient up to a maximum follow-up period of 4 years., Conclusion: Counterbalancing is a useful technique to overcome the problem of warping. It gives liberty to utilize even unbalanced cartilage safely to provide desired shape and use the cartilage without any wastage.

Background. Xanthogranulomatous inflammation is an uncommon affection of the female genital tract. The youngest case reported of xanthogranulomatous salpingooophoritis in literature was by Shilpa et al. in 2013 in an eighteen-year-old female. Case Report. We report a case of 2-year-old female child with right-sided xanthogranulomatous salpingooophoritis presented as mass in abdomen. This is a case report of the youngest documented case of xanthogranulomatous salpingooophoritis in literature. As per abdominal examination, there was generalized distention of abdomen and a mass was palpable which was arising out of pelvis more on the right side. The ultrasonography (USG) abdomen and pelvis revealed a thick-walled mass measuring 9.2 cm × 6.0 cm × 7.6 cm in pelvis. We did right salpingooophorectomy of the patient. On histopathology, the diagnosis of xanthogranulomatous salpingooophoritis was confirmed. Conclusion. Clinical presentation, radiological appearance, and gross features of xanthogranulomatous lesions of ovary can mimic neoplastic lesions and lead to misdiagnosis. Though, it is very rare in pediatric age group, xanthogranulomatous salpingooophoritis as one of the differential diagnoses should be kept in mind while dealing with tuboovarian masses in this age group.