Functional evaluation of the urinary tract by duplex Doppler ultrasonography in patients with acute renal colic

Purpose: To determine the role of duplex Doppler ultrasonography (DDU) in Patients with acute unilateral renal obstruction. Subjects And Methods:A total of 161 Patients with suspected renal colic due to urolithiasis were evaluated by DDU followed by intravenous urography (IVU). The mean intra-arterial resistive index (RI) and the difference of mean resistive index between both kidneys (delta RI) were determined for each person. An RI value of ≥0.70 and a delta RI value of ≥0.06 were taken as the discriminatory threshold for obstruction. IVU results were considered the reference standard against which renal DDU findings were compared. Results: IVU showed both kidneys to be normal in 51 Patients and with unilateral ureteric obstruction in 110 Patients. The mean RI for obstructed kidneys was 0.67 (0.048), which was significantly higher (P-value Conclusion: Delta RI is more sensitive and specific than RI in acute renal obstruction. However, due to relatively low sensitivity for detection of partial obstruction, DDU cannot replace IVU as the standard imaging technique

SnO2-SiO2 1D Core-Shell Nanowires Heterostructures for Selective Hydrogen Sensing

SnO2 is one of the most employed n-type semiconducting metal oxide in chemo-resistive gas-sensing although it presents serious limitations due to a low selectivity. Herein, the authors introduce 1D SnO2-SiO2 core-shell nanowires (CSNWs). The amorphous SiO2-shell layer with varying thicknesses (1.8–10.5 nm) is grown onto the SnO2 nanowires (NWs) by atomic layer deposition (ALD). SiO2-coated SnO2 CSNWs show a dramatic improvement of the selectivity towards hydrogen. Moreover, the sensing-response is strongly correlated to the thickness of the SiO2-shell and the working temperature. The SnO2-SiO2 CSNWs sensor with a 4.8-nm SiO2 shell thickness exhibits the best selectivity and sensitivity, having ca. 7-fold higher response toward hydrogen compared to bare-SnO2 NWs. The selectivity and enhanced sensing-response are related to the masking effect of the SiO2 shell and an increase in the width of the electron-depletion-layer due to a strong electronic coupling between the SnO2 core and SiO2 coating, respectively.Peer Reviewe

A fully automatized method for the unambiguous wavelength-by-wavelength determination of the thickness and optical property of a very thin film with a transparent range

Spectroscopic ellipsometry is a powerful method with high surface sensitivity that can be used to monitor the growth of even sub-monolayer films. However, analysis of ultrathin films is complicated by the correlation between the dielectric constant and thickness. This problem is usually resolved by fixing one or the other value, limiting the information that can be extracted. Here, we propose a method to determine unambiguously the refractive index, extinction coefficient, and thickness of a film when a transparent range is available in the energy range investigated. We decompose the analysis in three steps. First, the thickness of the film is determined from the transparent range of the film. Then, knowing the thickness of the layer, an initial estimation of the refractive index and extinction coefficient is made based on a first-order Taylor expansion of the ellipsometric ratio. Finally, using this estimation, a numerical iteration is done to ensure convergence of the fit toward the solution. A theoretical example of the method is given for two different thicknesses of TiO2 films. Finally, the method is applied to the experimental data measured during the atomic layer deposition of a thin film of Hf0.5Zr0.5O2 grown on Si. The thickness, refractive index, and extinction coefficient are retrieved with high precision (respectively, 0.01 and 0.002) in the energy range of 3.5–6.5 eV. A detailed analysis is presented on the accuracy of the retrieved values and their dependency on random and systematic errors for different energy ranges

Experience of managing acute pancreatitis in a surgical unit of a tertiary care hospital

Objective: To study the etiology, diagnosis, treatment and complications of acute pancreatitis in a tertiary care hospital.  Methodology: Study Design: It was a descriptive study. The study was conducted at Surgical Unit of Benazir Bhutto Hospital (BBH) Rawalpindi from 1st January 2014 to 31 July 2017.  All the patients who presented in emergency with abdominal symptoms and diagnosed as a case of acute pancreatitis were included in the study. All the data of gender, age, serum amylase & lipase, etiology, CT severity index, Ranson’s criteria, complications, mortality and management were noted on a predesigned proforma. Percentages and frequencies were calculated for all the data by SPSS 21 version. Results: Total 161 patients were included in the study, with 60.9% females and 39.1% males. Maximum patients 31% were from age group of 26 to 40  years of age and minimum 1.2% from 71 to 85 years. Gall stones were the major cause of the disease contributing 67% of cases.  At admission Ranson’s score of the maximum patients 32.2% had total score of 1, While only 1.2% had moderate pancreatitis.  After 48 hours of admission 24.2% had 2 score while only 1.2%had severe pancreatitis.  The radiological CT severity index 82.6% patients had mild pancreatitis while1.2% patients had severe disease. 93.1% patients were managed conservatively, 1.9%  patients went Cystogastrostomy, 1.2% patients needed Exploratory laparotomy and  1.2% patients went for Pancreatic Necrosectomy.  On calculating the morbidity 67.7% patients had no significant morbidity. 32.3% had complications including pleural effusion, ascites, pancreatic necrosis, pseudo cyst formation, shock, acute renal failure and multi organ failure.  Overall mortality rate was  3.7%. Conclusion: Acute pancreatitis in our set up is mainly due to gall stones. A multidisciplinary approach, measurement of severity of disease with computerized tomography scan and Ranson’s scoring system is always helpful in disease management and its complications. Key Words : Acute pancreatitis, Gall stones, Ranson’s scoring, Pancreatic necrosis, Pseudocyst

A fully automatized method for the unambiguous wavelength-by-wavelength determination of the thickness and optical property of a very thin film with a transparent range

Spectroscopic ellipsometry is a powerful method with high surface sensitivity that can be used to monitor the growth of even sub-monolayer film. However, the analysis of ultrathin films is complicated by the correlation of the dielectric constant and the thickness. This problem is usually resolved by fixing one or the other value, limiting the information that can be extracted. Here, we propose a method to determine unambiguously the refractive index, extinction coefficient and thickness of a film when a transparent range is available in the energy range investigated. We decompose the analysis in three steps. First, the thickness of the film is determined from the transparent range of the film. Then, knowing the thickness of the layer, an initial estimation of the refractive index and extinction coefficient is made based on a first-order Taylor expansion of the ellipsometric ratio. Finally, using this estimation, a numerical regression is done to ensure the convergence of the fit towards the solution. A theoretical example of the method is given for two different thicknesses of TiO2 films. Finally, the method is applied to the experimental data measured during the atomic layer deposition of a thin film of Hf0.5Zr0.5O2 grown on Si. The thickness, refractive index and extinction coefficient are retrieved with a high precision in the energy range of 3.5 - 6.5 eV. A detailed analysis is presented on the accuracy of the retrieved values and their dependency on random and systematic errors for different energy ranges

An institutional review of transarterial embolization in haemorrhagic urological emergencies

OBJECTIVE: To review the effectiveness of therapeutic transarterial embolization in controlling phagic urological emergencies irrespective of the cause of emergencies. METHODS: Thirty-seven vascular angiographies were performed in 32 patients (19 males and 13 females, age range 19-70 years) who were referred with haemorrhagic urological emergencies to Aga Khan University Hospital\u27s angiography suite from July 2005 to June 2010. Embolization was performed with coils, polyvinyl alcohol particles, N-Butyl cyanoacrylate glue and gel foam according to the clinical indication. Data on clinical indication, technique, site and type of bleeding lesions were obtained from a retrospective review of medical records. Success rate, clinical outcome and complications of the procedure were analysed. RESULTS: Indications of procedure included iatrogenic injury (16), Renal mass on clinical examination and imaging (4), haematuria with pseudoaneurysm on examination (3), haematuria with no known cause (3), post traumatic renovascular injury (2) Renal arteriovenous fistulas (2), Carcinoma of prostate (1) and pelvic arteriovenous (AV) fistula (1). Twenty four patients underwent successful endovascular control of bleeding. Eight examinations were negative for active extravasation, two of whom showed haemorrhage in second session and were embolized. Two sessions were needed in two patients at different time intervals. Complication as dislodgement of coil in distal profunda femoris artery was seen in one patient with no significant obstruction to flow. CONCLUSION: Transarterial renal angioembolisation is a safe and effective therapeutic tool for managing haematuria or haemorrhage in urological emergencies. Wherever and whenever indicated it should be the first preferred treatment modality

Microbial Contamination in Drinking Water of Saggiyan-Lahore, Pakistan

The present study was carried to evaluate the physico-chemical parameters and microbial contamination of drinking water in the area of Saggiyan, Lahore. The tested water samples (S1-S30) were found to contain 199.6-402 mg/L TDS, 196-260 ppm EC, 196-260 ppm Hardness, 0.8-17 NTU turbidity, 169-290 mg/L alkalinity, 0-0.1 ppb arsenic and 0-0.1 ppm fluoride contents. 95% of the water samples were found contaminated with fecal coliforms while 27% of the samples had shown the presence of E. coli. Though the physico-chemical parameters of most water samples were found in the safe limits of WHO, however, the presence of microbial contamination rendered it non-suitable for drinking purposes

Gas Sensing of NiO-SCCNT Core–Shell Heterostructures

Hierarchical core–shell (C–S) heterostructures composed of a NiO shell deposited onto stacked‐cup carbon nanotubes (SCCNTs) are synthesized by atomic layer deposition (ALD). A film of NiO particles (0.80–21.8 nm in thickness) is uniformly deposited onto the inner and outer walls of the SCCNTs. The electrical resistance of the samples is found to increase of many orders of magnitude with the increasing of the NiO thickness. The response of NiO–SCCNT sensors toward low concentrations of acetone and ethanol at 200 °C is studied. The sensing mechanism is based on the modulation of the hole‐accumulation region in the NiO shell layer upon chemisorption of the reducing gas molecules. The electrical conduction mechanism is further studied by the incorporation of an Al2O3 dielectric layer at NiO and SCCNT interfaces. The investigations on NiO–Al2O3–SCCNT, Al2O3–SCCNT, and NiO–SCCNT coaxial heterostructures reveal that the sensing mechanism is strictly related to the NiO shell layer. The remarkable performance of the NiO–SCCNT sensors toward acetone and ethanol benefits from the conformal coating by ALD, large surface area of the SCCNTs, and the optimized p‐NiO shell layer thickness followed by the radial modulation of the space‐charge region. Peer Reviewe