Modulating the Morphological Features of Hydrothermally Derived Nickel Cobaltite for Supercapacitor Application: Role of Precursor Anions.

Morphologically engineered porous electrodes show great promise in energy applications as they exhibit improved electrochemical activity owing to increased electrical conductivity, increased surface area, and a shorter path length for ion transport. Herein, the role of precursors (chlorides, acetates and nitrates) on the crystallinity and textural features of Nickel Cobaltite, obtained by the controlled precipitation through hydrothermal synthesis, is studied. The synthesis yielded urchin like structures with morphological variations in substructures based on the precursor anion types. The surface area values obtained for nickel cobaltite derived from the chloride (NCO-C), nitrate (NCO-N), and acetate precursors (NCO-A) were 30,110 and 115 m2 g-1 , confirming the influence of anions on the textural features. The time dependant electrolyte (2 M KOH) infiltration behaviour on the electrode surfaces based on contact angle measurements is invoked to correlate its morphological and textural attributes with the electrolyte transport kinetics. The electrochemical performances were derived from cyclic voltammetry, galvanostatic charge discharge analysis and impedance measurements. The electrolyte infiltration studies established a dependence on the precursor anion. NCO-A facilitated faster electrolyte infiltration time of 7800 ms compared to 16200 ms and 54,000 ms for NCO-N and NCO-C electrodes, respectively. Furthermore, NCO-A exhibited a greater specific capacitance of 802 F g-1 than NCO-N (500 F g-1 ) and NCO-C (342 F g-1 ). The morphology modulation coupled with optimal porosity led to conducive pathways for reversible electrolyte infiltration resulting in increased capacitive contribution in NCO-A. The study revealed that the size of intercalating anions exercised a significant impact on the morphological and electrochemical features, signifying the importance of synthetic approaches in determining the functional properties of electrode materials.

Degradation-Dependent Controlled Delivery of Doxorubicin by Glyoxal Cross-Linked Magnetic and Porous Chitosan Microspheres.

Glyoxal cross-linked porous magnetic chitosan microspheres, GMS (∼170 µm size), with a tunable degradation profile were synthesized by a water-in-oil emulsion technique to accomplish controlled delivery of doxorubicin (DOX), a chemotherapeutic drug, to ensure prolonged chemotherapeutic effects. The GMS exhibit superparamagnetism with saturation magnetization, M s = 7.2 emu g-1. The in vitro swelling and degradation results demonstrate that a swelling plateau of GMS is reached at 24 h, while degradation can be modulated to begin at 96-120 h by formulating the cross-linked network using glyoxal. MTT assay, live/dead staining, and F-actin staining (actin/DAPI) validated the cytocompatibility of GMS, which further assured good drug loading capacity (35.8%). The release mechanism has two stages, initiated by diffusion-inspired release of DOX through the swollen polymer network (72 h), which is followed by a disintegration-tuned release profile (>96 h) conferring GMS a potential candidate for DOX delivery.

Sodium silicate-derived aerogels: effect of processing parameters on their applications.

Inorganic silica aerogels derived from sodium silicate are voluminous three-dimensional open networks with exceptional properties such as a density as low as ∼100 kg m-3, high porosity (∼99%), low thermal conductivity (∼0.01 W m-1 K-1), high specific surface area (∼1000 m2 g-1), low refractive index (∼1.05) and high optical transmittance (∼95%) depending on their preparation conditions. They are processed through the sol-gel route, which is a reliable methodology to produce high-grade porous materials. Ambient pressure drying has been developed as a low-cost route for the preparation of sodium silicate-derived aerogels, overcoming the difficulties with the use of organosilane precursors and super critical drying. Silica aerogels can be hydrophobic or hydrophilic depending on their synthetic procedure and surface silanol groups. Owing to their unusual properties, these inorganic aerogels have been applied in both commercial and high-tech engineering applications such as thermal insulation, separation, coatings, optics, nuclear particle detection, sensing, and catalysis. This review provides information on the unique features of a wide array of silica aerogels and their potential applications and recent developments in the field of science and technology.

Surface modification induced enhanced CO2 sorption in cucurbit[6]uril, an organic porous material.

The CO2 adsorption properties of an organic macrocycle, cucurbit[6]uril (CB[6]), have been evaluated through experimental and theoretical studies. Quantum mechanical calculations show that CB[6] is capable of adsorbing the CO2 molecule selectively within its cavity relative to nitrogen. Adsorption experiments at 298 K and at 1 bar pressure gave a CO2 adsorption value of 1.23 mmol g-1 for the unmodified material. Significant enhancements in the CO2 adsorption capacity of the material were experimentally demonstrated through surface modification using physical and chemical methods. Ethanolamine (EA) modified CB[6] provided an excellent sorption selectivity value of 121.4 for CO2/N2 at 323 K and is unique with respect to its discrimination potential between CO2 and N2. The chemical nature of the interaction between CO2 and amine is shown to be the primary mechanism for the enhanced CO2 absorption performance.

Role of precursors on the photophysical properties of carbon nitride and its application for antibiotic degradation.

In this paper, we provide a comprehensive evaluation of graphitic carbon nitride (C3N4) powders derived from the four different precursors melamine, cyanamide, thiourea, and urea for the photocatalytic degradation of tetracycline (TC) antibiotic under sunlight irradiation. The powders were synthesized by employing the conventional thermal decomposition method. The synthesized powders were examined using different characterization tools for evaluating the photophysical properties. The degradation profile revealed that urea-derived C3N4 showed the highest activity while melamine-derived C3N4 showed the least activity. The TC degradation efficiency of the photocatalyst was found to be influenced more by the surface area values despite extended absorption by melamine in the visible light region. Stability tests on urea-derived C3N4 and others were checked by four runs of TC degradation under sunlight irradiation. The synthesized C3N4 powders also confirmed the dominance of urea-derived powders for cyclic stability.

Graphene Oxide Sheathed ZIF-8 Microcrystals: Engineered Precursors of Nitrogen-Doped Porous Carbon for Efficient Oxygen Reduction Reaction (ORR) Electrocatalysis.

Nitrogen containing mesoporous carbon obtained by the pyrolysis of graphene oxide (GO) wrapped ZIF-8 (Zeolitic Imidazolate Frameworks-8) micro crystals is demonstrated to be an efficient catalyst for the oxygen reduction reaction (ORR). ZIF-8 synthesis in the presence of GO sheets helped to realize layers of graphene oxide over ZIF-8 microcrystals and the sphere-like structures thus obtained, on heat treatment, transformed to highly porous carbon with a nitrogen content of about 6.12% and surface area of 502 m2/g. These catalysts with a typical micromeso porous architecture exhibited an onset potential of 0.88Vvs RHE in a four electron pathway and also demonstrated superior durability in alkaline medium compared to that of the commercial Pt/C catalyst. The N-doped porous carbon derived from GO sheathed ZIF-8 core-shell structures could therefore be employed as an efficient electrocatalyst for fuel cell applications.

Hydrophobic and Metallophobic Surfaces: Highly Stable Non-wetting Inorganic Surfaces Based on Lanthanum Phosphate Nanorods.

Metal oxides, in general, are known to exhibit significant wettability towards water molecules because of the high feasibility of synergetic hydrogen-bonding interactions possible at the solid-water interface. Here we show that the nano sized phosphates of rare earth materials (Rare Earth Phosphates, REPs), LaPO4 in particular, exhibit without any chemical modification, unique combination of intrinsic properties including remarkable hydrophobicity that could be retained even after exposure to extreme temperatures and harsh hydrothermal conditions. Transparent nanocoatings of LaPO4 as well as mixture of other REPs on glass surfaces are shown to display notable hydrophobicity with water contact angle (WCA) value of 120° while sintered and polished monoliths manifested WCA greater than 105°. Significantly, these materials in the form of coatings and monoliths also exhibit complete non-wettability and inertness towards molten metals like Ag, Zn, and Al well above their melting points. These properties, coupled with their excellent chemical and thermal stability, ease of processing, machinability and their versatile photo-physical and emission properties, render LaPO4 and other REP ceramics utility in diverse applications.

Laparoscopic pyelolithotomy: An emerging tool for complex staghorn nephrolithiasis in high-risk patients.

OBJECTIVES: To evaluate the effectiveness of laparoscopic pyelolithotomy (LP) for staghorn stones (>3-4 cm) in patients with chronic liver disease or coronary artery disease. PATIENTS AND METHODS: In all, 49 patients underwent LP; they were divided into four groups, with stones in group 1 in the renal pelvis only, in group 2 in the renal pelvis and one calyx, in group 3 in the renal pelvis and two calyces, and in group 4, in the renal pelvis and more than two calyces. Patient demography, stone characteristics, surgical outcomes and complications were evaluated. RESULTS: The mean stone-free rate in one session was 90% among all groups. The mean (SD) stone size was 4.27 (1.72) cm. The stone-free rate decreased with greater stone burden, but the operative time, estimated blood loss and need for ancillary procedures increased with stone burden. No blood transfusion was required and one patient each in groups 2 and 4 had a urine leak. CONCLUSION: LP provides acceptable results in complex cases for managing renal stone disease with a larger stone burden in high-risk situations.

Bifunctional lanthanum phosphate substrates as novel adsorbents and biocatalyst supports for perchlorate removal.

Porous lanthanum phosphate substrates, obtained by an environmentally benign colloidal forming process employing methyl cellulose, are reported here as excellent adsorbents of perchlorate with >98% efficiency and with 100% reusability. Additionally, the effectiveness of such substrates as biocatalyst supports that facilitate biofilm formation of perchlorate reducing microbes (Serratia marcescens NIIST 5) is also demonstrated for the first time. The adsorption of perchlorate ions is attributed to the pore structure of lanthanum phosphate substrate and the microbial attachment is primarily ascribed to its intrinsic hydrophobic property. Lanthanum phosphate thus emerges as a dual functional material that possesses an integrated adsorption/bioremediation property for the effective removal of ClO4(-) which is an increasingly important environmental contaminant.

Renal Cell Carcinoma Associated with Xp11.2 Translocation/TFE3 Gene Fusion: A Rare Case Report with Review of the Literature.

Introduction. The recently recognized renal cell carcinomas associated with Xp11.2 translocations are rare tumors predominantly reported in children. Chromosome Xp11.2 translocation results in gene fusion related to transcription factor E3 (TFE3) that plays an important role in proliferation and survival. Case Report. Herein, we present two cases of a TFE3 translocation-associated RCC in young female adults, one detected incidentally and the other one presenting with gross hematuria. Tumor is characterized by immunohistochemistry and a literature review with optimal treatment regimen is presented. Discussion. Xp11.2 translocation RCCs in adult patients are associated with advanced stages, large tumors, and extracapsular disease and usually have an aggressive clinical course. Conclusion. In TFE3 RCC, the genetic background may not only contribute to tumorigenesis, but also determine the response to chemotherapy and targeted therapy. Therefore it is necessary to diagnose this tumor entity accurately. Because of the small number of TFE3 gene fusion-related renal tumors described in the literature, the exact biologic behavior and impact of current treatment modalities remain to be uncertain.

Laparoscopic adrenal surgery in children: Lessons from a single centre experience.

PURPOSE: Although commonly performed in adults, laparoscopic adrenalectomy in children is performed only in centres with advanced laparoscopic expertise. MATERIALS AND METHODS: This is a retrospective analysis of laparoscopic adrenalectomies performed at a single centre between January 2003 and May 2010. After preoperative evaluation with biochemical assays and radiologic imaging, surgery was performed by using the lateral transabdominal approach in all patients. RESULTS: Ten laparoscopic adrenalectomies (including three bilateral) were performed in seven children, with a mean age of 9.6 years. The tumours ranged from 2 - 7 cms in size. The operative durations were 75 - 130 minutes (unilateral) and 250 - 270 minutes (bilateral). Operative blood loss was minimal. There were no open conversions, but terminal hand assistance was required in one large right pheochromocytoma. The postoperative hospital stay ranged from 3 - 10 days. The final pathological diagnoses included pheochromocytoma, hyperplasia and neuroblastoma. Follow-up at 24 - 87 months was uneventful. CONCLUSION: With adequate experience in laparoscopy, it is possible to perform adrenalectomy in selected children.

Adult presentation of congenital ectopic vas deferens insertion into ureter with unilateral renal agenesis.

Congenital vas deferens-ureteral connection is known to cause epididymitis and scrotal infections in infancy and childhood. Embryologically, the anomaly results from an abnormal high origin of the ureteric bud on the mesonephric duct with a resultant long common excretory duct being incompletely absorbed into the bladder. This report describes a rare adult presentation in a 20-year-old man where evaluation with ultrasonograms, isotope renogram, magnetic resonance imaging scans and cystoscopy with retrograde instillation of contrast into the right ureter confirmed aberrant insertion of vas deferens into the ureter associated with ureterocele and ipsilateral renal agenesis.

Concomitant laparoscopic urological procedures: Does it contribute to morbidity?

AIM: With advancement in minimal access surgery two laparoscopic procedures can be combined together shortening the total hospital stay, decreasing morbidity and overall reduced cost. Combining two laparoscopic procedures in a single session has been reported in general surgery. Very few articles are available in literature with regard to combined urological laparoscopic surgeries. This article retrospectively analyses the outcomes of multiple laparoscopic procedures performed in a single stage at our centre. MATERIALS AND METHODS: Patients undergoing simultaneous procedures from May 2003 to Jan 2009 were included in the study. Patients were categorised into three groups according to the primary urological organ involved, for better comparison with the control group. Diseases involving the adrenals gland were grouped in (group 1), kidney (group 2) and renal collecting system/ureter (group 3). All patients had one urological procedure for either of the above-mentioned organs combined with another surgical procedure. Similarly three control groups were chosen according to the primary urological organ involved (group 1c- unilateral laparoscopic adrenalectomy, group 2c- unilateral laparoscopic radical nephrectomy and group 3c- unilateral laparoscopic ureterolithotomy) for comparative study. The operative details, hospital stay and complications were analysed. RESULTS: Thirty-two patients underwent 64 laparoscopic procedures under single anaesthesia. The most common procedure in this series was laparoscopic adrenalectomy (n=34) followed by laparoscopic nephrectomy (n=13). Group 1 patients had a prolonged operative time ( P=0.012) and hospital stay ( P=0.025) when compared with group 1c. However, blood loss was comparable in both the groups. Patients in groups 2 and 3 had comparable operative times, blood loss and recovery period with respect to their controls. Intraoperatively, the end tidal carbon dioxide levels were within permissible limits. All procedures were completed using the laparoscopic approach, without any conversion. CONCLUSIONS: Simultaneous laparoscopic procedures can be done for urological diseases in selected patients with the advantages of single anaesthesia and hospital admission without increasing the morbidity.

Laparoscopic assisted dismembered pyeloplasty in children: intermediate results.

To study the results of an innovative minimally invasive technique of performing dismembered pyeloplasty in children. Using 5 mm camera and 3 mm working ports, the ureteropelvic junction (UPJ) is mobilized by a transperitoneal laparoscopic technique. The UPJ is brought out through a tiny flank incision and a standard dismembered pyeloplasty is performed over a double J stent. Between October 2003 and January 2005, 13 children underwent laparoscopic assisted dismembered pyeloplasty. Indications, operative duration, hospital stay, preoperative and postoperative isotope renogram parameters were analyzed. The children were in the age range of 3 months to 6 years-three were right sided and ten were left sided. Only three were symptomatic while the remaining ten were detected to have UPJ obstruction during evaluation for antenatally detected hydronephrosis. Mean operative duration was 104.2 min (range 80-150 min) with no significant difference in the two patients with crossing vessels. Incision was smaller than 2 cms in all and the average postoperative hospital stay was 3.2 days (range 2-5 days). Follow-up ranging from 28 to 44 months showed reduction in hydronephrosis and improvement in renal function of all the operated units. Isotope renogram in only one patient showed equivocal slopes and prolonged half clearance times though no further surgical intervention was required. This technique has results comparable to that of open pyeloplasty and hence, maybe considered a good option for surgeons making the transition to laparoscopic pyeloplasty.

Supracostal access for percutaneous nephrolithotomy: less morbid, more effective.

OBJECTIVES: The aim of this research was to study the success and morbidity of supracostal access for percutaneous nephrolithotomy (PCNL), as it is often avoided for fear of complications. MATERIALS AND METHODS: Between July 2000 and May 2007, 565 patients underwent PCNL, of whom 110 had a supracostal access. All procedures were performed in a single sitting under general anesthesia. Data were analyzed prospectively for indications, stone clearance rates, and preoperative and postoperative complications. RESULTS: Indications for supracostal access included large pelvic stones in 39 patients, partial or complete staghorn stones in 32, calyceal stones with major stone bulk above the level of 12th rib in 35, and upper ureteric stones in four. Patients' ages ranged between 13 and 71 years (mean 44.2 years). Fifty-six cases were left sided and 54 right sided, whereas 103 (93.6%) were radiopaque stones. All tracts were in the 11th intercostal space, though one had an additional tract in the tenth space. Single-tract access was used in 101 cases (91.8%), but nine (8.2%) required a second tract. Overall stone clearance rate with PCNL monotherapy was 86.4%, and this increased to 97.3% with secondary procedures. Overall complication rate was 11.8% and included hydrothorax/hemothorax in ten, perinephric collection in one, infection/sepsis in two, and excessive bleeding in two. Postoperative hospital stay ranged from 2 to 15 days. CONCLUSIONS: The supracostal approach gives high stone clearance rates with acceptable morbidity rates and should be attempted in selected cases. Complications when present may be managed easily with conservative measures.

Solitary fibrous tumour of prostate: evaluation and management of a rare tumour.

Solitary fibrous tumours, which are commonly described as arising from the pleura, are rarely seen in the lower urinary tract. Although malignant changes have been reported, these tumours are usually benign. This case report discusses the radiological features, management strategy and histopathology of a solitary fibrous tumour arising from the prostate.

Azathioprine-induced squamous cell carcinoma of the kidney.

Immunosuppressive therapy with azathioprine has been documented to cause squamous cell carcinoma (SCC) at various sites. We report possibly the first case of SCC of the kidney in a young male who received azathioprine for a long time. Discontinuation of azathioprine post-radical nephrectomy probably increased the patient's metastatic disease-free survival.