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Non-stoichiometric lead free polycrystalline Sr0.8Sn0.2Bi1.75Sm0.25Nb2O9 (SSBSN) ferroelectric ceramics were synthesized through conventional solid step route method by incorporating ball milling and microwave sintering method. X-ray diffraction along with the Rietveld refinement technique confirms the single-phase orthorhombic structure with A21 crystal symmetry. Additionally, the short-range ordering was confirmed by Raman spectroscopy. Doping induced crystallite size and strain were further calculated from the Williamson-Hall plot, which comes around 150 nm and 1.48 × 10–3 respectively. A plate like morphology with an average grain size of 0.41 μm was confirmed by scanning electron microscopy (SEM). A diffuse type ferroelectric to paraelectric phase transition was recorded at 395 °C, mostly arising due to structural heterogeneity at the inter-ferroelectric phase boundary. The temperature and frequency-dependent dielectric measurement of SSBSN ceramic reveal a Maxwell–Wagner relaxation, with prominent dielectric loss in a low frequency regime perhaps due to the generation of leakage current in the SSBSN system. Frequency dependent ac conductivity indicates the polaron assisted hopping mechanism in SSBSN, which further obeys Jonscher’s formulation. The intra and intergranular contributions to impedance in SSBSN ceramics were probed by the complex impedance spectroscopy (CIS) technique. A non-Debye type relaxation mechanism in SSBSN ceramics was indicated by the Cole–Cole plot, whereas the conduction mechanism and transport properties were briefly studied using modulus spectroscopy. [ABSTRACT FROM AUTHOR]

Introduction: The misfortunate incident of formation of a urogenital fistula remains a major challenge for surgical urologists worldwide. Such fistulae may not be a life-threatening problem, but surely the women face demoralization, social boycott and even divorce and separation. The fistula may be vaginal, recto-vaginal or a combination of the two. The World Health Organization (WHO) has estimated that in the developing nations, nearly 5 million women annually suffer severe morbidity with obstetric fistulae being the foremost on the list. The objective of our study was to enunciate the patient demography, patient profile, incidence, type of surgery, as well as the long-term outcomes encountered in the management of all types of genital fistulae at a tertiary care centre. Materials and Methods: 50 consecutive patients, attending the outpatient department with urogenital fistulae, were studied during the period of 5 years from July 2005 to July 2009. All female patients with complaints of urinary incontinence and fecal incontinence and dribbling, patients having a history of obstructed labor, radiotherapy, instrumental delivery, foreign body or trauma and with a history of hysterectomy (abdominal/ vaginal) and lower segment caesarean section (LSCS) were included. A thorough urological examination included a dye study using methylene blue, Renal function tests, X-ray KUB and intravenous urography (IVU). Cystoscopy along with examination under anaesthesia (EUA) were done to assess the actual extent of injury. All patients were subjected to appropriate surgical interventions via the same combination of surgeons . Post operatively, prophylactic antibiotics were administered to all patients and patients were managed till discharge and followed thereafter via regular outpatient visits for a period of 3 years. Results: Age of patients ranged from 21 to 40 years. 64% patients hailed from rural areas, 76% were from the lower socio-economic strata, 40% illiterate and 69% were short Statured. Vesico vaginal fistulae (VVF) was seen in 64% cases of which 50% were due to obstructed labor, 19% cases post LSCS and 31% cases post total abdominal hysterectomy (TAH). 68% of urogenital fistulae were between 1 to 3 cms. We obtained a 75% cure rate in UVF, 87.5% cure rate in RVF while a 93.75% cure rate was observed in patients with VVF. 76% of all patients were cured while 8% had a recurrence, probably due to the large size of fistula. Conclusion : Genital fistula is preventable, yet it remains a significant cause of morbidity among females of reproductive age group. Despite facilities available, certain conditions like physical, social, economic, illiteracy, and a very casual attitude towards maternal health and children birth practices limit utilization of services for women. It is important that the modern health care providers should be aware of these aspects, so that they can recognize services that are appropriate and acceptable to the people. Thus, one must agree that in cases of urogenital fistulae, "prevention is better than cure".

Introduction: End-stage renal disease (ESRD) patients who need long-term hemodialysis often have dialysis fistulas created. Due to their long-term patency, high flow rates, and ability to be cannulated repeatedly, arteriovenous fistulas (AVFs) are the preferred access method. AVF creation connects an arm artery and vein to increase blood pressure and flow to the vein, which widens for hemodialysis. DUS (Doppler ultrasound) is the only diagnostic imaging method that simultaneously displays an area's anatomy (B-mode imaging) and blood supply (Color and Doppler imaging). Material and methods: The study was conducted on 40 patients at a department of surgery in central India from January to December 2022. Patients were divided into two groups: one with preoperative color doppler and the other based on clinical findings alone. Measurements were taken using the Aloka Prosound a-10 duplex machine, with the cephalic vein and brachial and radial arteries being measured. Result: 19 males and 21 females in Group A and 56.1 in Group B were enrolled. The study compared vascular access surgery patients with and without preoperative Doppler ultrasound scans. Age, sex, smoking status, and residence did not differ between groups. Vascular access was significantly different between the two groups. Group A had 75% left upper limb VA and 25% contralateral VA, while Group B had 65% left upper limb VA and 35% contralateral VA. Both groups had mostly urban non-smokers. Both groups had the most comorbidities: hypertension and hypercholesterolemia. Preoperative Doppler ultrasound scans improved vascular access surgery vessel selection. DUS and surgery showed significant differences in artery and vein diameter. DUS and clinical evaluations yielded 14 and 11 mature AVF, respectively. 12 DUS-functional and 8 clinical-functional. Statistical difference. DM and HTN comorbidities increased failure rate. Conclusion: The study analyzed the impact of preoperative duplex mapping for arterial and venous system and found that it reduces the failure rates in AV access surgery. The study compared the outcomes of AV access surgery based on clinical versus duplex method and found that the duplex method had a lower failure rate. The causes of early failure rates were also examined. The study identified the risk group that requires definite preoperative duplex mapping, which includes patients over 50 years old, female patients, and patients with comorbidities. However, the measurement by duplex scan is subject to operatordependent errors. [ABSTRACT FROM AUTHOR]

Featured Application: Use bio-based fertilisers as a replacement for mineral fertiliser or slurry manure. The refinement level of bio-based fertilisers (BBFs) can influence environmental and agronomic performance. This study analyses the environmental and agronomic effect of different BBFs on potato growing in sandy soil. A less refined product (liquid fraction of digestate (LFD)), two refined products (ammonium sulphate (AS) and potassium concentrate (KC)), and mineral fertilizer (MF) are compared by conducting: (i) a nitrogen (N) incubation experiment where the N release rate of the BBFs is determined, (ii) a greenhouse gas emission experiment where N2O, CO2, and CH4 emissions after BBF application are measured, (iii) a pot experiment where the nutrient fertiliser replacement value (NFRV) of the BBF is calculated, and (iv) a full-scale field trial where the potato quality and quantity and the remaining N residues in the soil after harvest are assessed. The N release rate and the NFRV of AS (142 ± 19% and 1.13, respectively) was higher compared with the LFD (113 ± 24% and 1.04) and MF (105 ± 16% and 1.00). Lowest N2O emissions were observed after the application of the less refined product (0.02 ± 0.01 per 100 g N applied) and highest for MF urea (0.11 ± 0.02 per 100 g N applied). In the full-scale field trial, no significant difference in potato yield was observed in the plots that received manure in combination with BBF or MF. This study showed that all three BBFs can safely be used in potato growing on sandy soils. However, the adoption of BBFs can be stimulated by (i) solving the practical issues that occurred during the application of LFD, (ii) making sure BBFs are on the list of RENURE materials so they can legally replace mineral fertiliser, and (iii) reducing the surplus of slurry manure to stimulate the use and fair pricing of BBF products. [ABSTRACT FROM AUTHOR]

Dual‐peak electrocaloric effect (ECE) exists over a broad range significantly below Curie temperature in co‐mixed SrBi1.98La0.02Nb2–xTaxO9 (SBLNT) compositions exhibiting diffused phase transition. The indirect measurement method is used to study the influence of defect‐modified potential barrier distributions on the ECE of lead‐free SBLNT ceramics. Variation in isothermal entropy change and adiabatic temperature change with varying tantalum (Ta) content signify effects of morphology and impact of altered potential barriers in the parent lattice without involving structural phase transition. A unique appearance of twin‐peak positive–negative ECE in equally doped SrBi1.98La0.02Nb‐TaO9 matrix is attributed to doping‐induced formation of polar nanoregions and distinct dipole switching mechanisms controlled by evenly distributed Nb–Ta potential barriers in SBLNT lattice. Higher doping concentration reduces porosity and promotes electric polarization, thereby the relative cooling power gradually increases with increasing Ta at Nb sites. [ABSTRACT FROM AUTHOR]

Hume‐Rothery rules along with Vegard's law form the basis of systematic doping variation resulting into similar changes in unit cell parameters and volume. Many recent reports have highlighted positive–negative departure from Vegard's law in binary semiconducting systems and a few oxide alloys as well. The current work targets investigations on the missing response of bismuth molybdate on low tungsten doping onto molybdenum sites (Bi2Mo1−xWxO6). Bismuth molybdate and bismuth tungstate have been widely reported for lattice oxygen migration‐driven photocatalytic response and pressure‐sensitive Raman scattering. Octahedral tilting in low‐tungsten‐doped Bi2Mo0.94W0.06O6 carries an interesting lattice oxygen folding toward a–c plane. As a result, unit cell polarity increases drastically and becomes a source for intense Raman scattering phase that is normally observable at pressures around 8.3 GPa. An interesting departure from Vegard's law behavior at around 5–6% tungsten doping confirms nearly identical unit cell structure rather than mix unit cell‐based alloy formation. [ABSTRACT FROM AUTHOR]