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Nanoscale SnO2, SnS2 and SnO2/SnS2 were synthesized by hydrothermal treatment method and characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Brunauer-Emmett-Teller (BET), Barrett-Joyner-Halenda (BJH) and UV-vis spectra. The photocatalytic activity of SnO2, SnS2 and SnO2/SnS2 were tested with Enrofloxacin antibiotic. The tetragonal and hexagonal SnO2 and SnS2 phase was confirmed through XRD, respectively. The photocatalytic results indicated that the SnO2/SnS2 enhanced the photocatalytic activity and could be effectively used as photocatalyst for degradation of Enrofloxacin antibiotic pollutant. The results of antibacterial experiment under visible light irradiation demonstrate that the SnO2/SnS2 nanocomposite exhibit enhanced antibacterial efficiency compared with pure SnO2 and SnS2. The antifungal activity of the nanoscale SnO2, SnS2 and SnO2/SnS2 against Candida albicans was assessed using the disc-diffusion susceptibility tests. It was seen that the antifungal activity of SnO2/SnS2 nanocomposite is higher than the pure SnO2 and SnS2 toward pathogenic C. albicans.

Background: Nowadays task sharing is a way to optimize utilization of human resources for health. This study was designed to assess the effect of task sharing, mutually between midwives and Family Health Workforces (FHWs), on the number of needed staff across the Iranian Health Posts. Methods: The workload and required number of midwives and FHWs in a Health Post were calculated and compared in two different scenarios of task division using a combined approach for estimating the number of required staff. In the first scenario, the midwives and FHWs provide their specialized services and in the second one, using mutual task sharing, a midwife provides all services traditionally delivered by FHWs and each FHW provides prenatal care in addition to the special tasks. Sensitivity analysis was performed to estimate the effects of different hypotheses. Results: By applying mutual task sharing, the required number of staff for Health Posts was one midwife and two FHWs for a standard population of 12,500; one FHW less than that when no task sharing was applied. Sensitivity analysis illustrated that the number of needed staff is the same in both scenarios when different demographic, epidemiologic, cultural and organizational conditions were applied. Conclusion: Task sharing can reduce the required number of health workers which increases efficiency and productivity at health facilities. However, apart from a need to consider quality, acceptability, and feasibility of care, increasing efficiency must be judged against the contextual circumstances.

We present a case of a 59-y-old woman who had undergone cholecystectomy and was subsequently found to have an abscess within the gallbladder fossa. A hepatobiliary scan using (99m)Tc-diisopropyliminodiacetic acid demonstrated the characteristic rim sign, a photopenic defect surrounded by a rim of mildly increased activity immediately adjacent to the gallbladder fossa. The rim sign was thought to be the result of reactive inflammation in the hepatic tissue adjacent to a postoperative abscess within the gallbladder fossa.

N-, S-, and C-doped SnO2 nanoparticles were synthesized via a precipitation method and were characterized by X-ray diffractometer (XRD), X-ray photoelectron spectra (XPS), scanning electron microscopy (SEM), Transmission Electron Microscope (TEM), UV–vis diffuse reflectance spectral (UV–vis DRS) and Brunauer–Emmett–Teller (BET) techniques. The photocatalytic activities of these SnO2 samples were investigated with methyl orange as the organic pollutant under UV light illumination. UV–vis spectroscopy demonstrated that dopants N,S,C-species can shift the absorption edge to the near UV and visible light region. N,S,C-SnO2 nanoparticles achieved the best photocatalytic efficiency and the most optimal doping ratio was 3 (T/S). The degradation of methyl orange by N,S,C-SnO2 nanoparticles fitted well with the Langmuir–Hinshelwood kinetics model. The results of subsequent experiments indicate that enhanced adsorption ability of light and high separation rate of photo induced charge carriers all play an major role in promotion of photocatalytic activity of N,S,C-SnO2 nanoparticles.

Drinking water resources may be contaminated with Ethidium Bromide (EtBr) which is commonly used in molecular biology laboratories for DNA identification in electrophoresis. Carbon nanotubes are expected to play an important role in sensing, pollution treatment and separation techniques. In this study adsorption of Ethidium Bromide on single-walled carbon nanotubes (SWCNTs) and carboxylate group functionalized single-walled carbon nanotube (SWCNT-COOH) surfaces have been investigated by UV–vis spectrophotometer. The effect of contact time, initial concentration and temperature were investigated. The adsorbents exhibits high efficiency for EtBr adsorption and equilibrium can be achieved in 6 and 3 min for SWCNTs and SWCNT-COOH, respectively. The effect of temperature on adsorption of EtBr by toward adsorbents shows the process in this research has been endothermic. The results showed that the equilibrium data were well described by the Langmuir isotherm model, with a maximum adsorption capacity of 0.770 and 0.830 mg/g for SWCNTs and SWCNT-COOH, respectively. The adsorption of EtBr on SWCNT-COOH is more than SWCNTs surfaces. A comparison of kinetic models was evaluated for the pseudo first-order, pseudo second-order models. Pseudo second-order was found to agree well with the experimental data.

Samples of surface sediments from the Iranian coast of the Persian Gulf were examined to determine the levels and sources of 15 polycyclic aromatic hydrocarbons (PAHs). Samples were collected from 30 sampling sites and analyzed for PAHs by gas chromatography-mass spectrometry (GC-MS). Total concentrations of PAHs ranged from 93 to 4,077 ng g(-1) dry weight. The PAH composition from 30 sampling sites was dominated by four-ring PAH compounds. Molecular indices based on the ratios of PAH concentrations were used to differentiate PAHs from pyrolitic to petrogenic and mixed origins. The results suggested that the main sources of PAHs in sediments from the studied region were mixed pyrolitic and petrogenic. Furthermore, benthic organisms in most of the investigated areas were not at ecotoxicological risk, according to the results from the effects range low (ERL)/effects range median (ERM) techniques suggested by the US Sediment Quality Guidelines (SQGs).

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The present study was undertaken to develop an effective adsorbent and to study the adsorption of Ethidium bromide and Ethidium monoazide bromide from aqueous solution using the CuO nanoparticles. The characteristics of CuO nanoparticles were determined and found to have a surface area 89.59 m 2 /g. Operational parameters such as pH, contact time and adsorbent concentration, initial concentration and temperature were also studied. The amount of removal increases with the increase in pH from one to seven and reaches the maximum when the pH is nine. Adsorption data fitted well with the Langmuir, Freundlich and Florry–Huggins models. The results show that the best fit was achieved with the Langmuir isotherm equation with maximum adsorption capacities of 0.868 and 0.662 mg/g for Ethidium bromide and Ethidium monoazide bromide, respectively. The adsorption process was found to follow pseudo-second-order kinetics. The calculated thermodynamic parameters, namely Δ G , Δ H and Δ S showed that adsorption of Ethidium bromide and Ethidium monoazide bromide was spontaneous and endothermic under examined conditions.

The adsorption of ethidium bromide (EtBr) by single-walled carbon nanotubes (SWCNTs) and nanoscale of zero valent iron (NZVI) were investigated to assess its possible use as adsorbents. The effect of various factors, namely initial adsorbate concentration, adsorbent dosage, and contact time, were studied to identify adsorption capacity of SWCNTs and NZVI surfaces. The experiment demonstrated the maximum EtBr which was obtained at 5 min to attain equilibrium for SWCNTs and NZVI surfaces. Adsorption data were modeled with the Langmuir, Freundlichand, Temkin isotherms. Langmuir adsorption model was used for the mathematical description of the adsorption equilibrium, and the equilibrium data fitted very well with this model for both surfaces as adsorbents. The study showed that SWCNTs and NZVI surfaces could be used as new and efficient adsorbent materials for the removal of EtBr from aqueous solution. Also, the result showed that the SWCNTs were more effective than NZVI in the removal of EtBr from aqueous solution.

In the high volume general practitioner setting, there is a need for triaging clinical questions pertaining to specific patients into ones that are readily answered, and those that would more effectively and efficiently be answered by the subspecialist. In this way, the nuclear medicine consultation provides the general practitioner a physiologic imaging specialist's perspective for answering complex clinical questions. A formal nuclear medicine consultation can be a valuable tool in identifying a targeted molecular imaging approach to answering a specific clinical question and can prove useful in both appropriate diagnostic study selection as well as accurate image interpretation.

We present a case of a 79-year-old immunocompromised female admitted for abdominal pain and sepsis, who had an abdominal computed tomography (CT) showing distal gallbladder fundus wall thickening, pericholecystic edema, and a right posteroinferior hepatic abscess. Subsequent hepatobiliary scintigraphy with Tc-99m diisopropyliminodiacetic acid showed gallbladder filling of the proximal gallbladder fundus, yet no radiotracer filling of the distal gallbladder fundus. Further correlation with the initial CT showed a partial gallbladder stricture and a resultant altered morphology resembling a dumbbell-shaped gallbladder. Percutaneous cholangiogram also confirmed this dumbbell morphology. Nonfilling of radiotracer into the distal end of the dumbbell gallbladder correlating with CT findings of focal gallbladder inflammation indicated that there was a focal inflammation suggesting a distal dumbbell gallbladder cholecystitis. This case demonstrates a unique finding of focal inflammatory pathology involving an anatomic variant - the dumbbell-shaped gallbladder, and the challenges this anatomic variant presents in hepatobiliary scintigraphy image interpretation.

The removal of 4-Chloro-2-nitrophenol (4C2NP) from aqueous solutions using zero valent iron nanoparticles (nZVI) and Pd-doped zero valent iron nanoparticles (Pd-nZVI) was investigated in terms of initial pH, adsorbent dosage, contact time and temperature. The maximum adsorption occurred at the pH value of 5. The adsorbent studied exhibits high efficiency for 4C2NP adsorption and the equilibrium states could be achieved in 10 min in both the adsorbents. Equilibrium data were analyzed by two isotherms, namely the Freundlich isotherm and the Langmuir isotherm. The best fit to the data was obtained with the Langmuir isotherm. Adsorption kinetics data were modeled using the first order, the pseudo-first and pseudo-second order and Elovich equations. Results show that the pseudo-second order kinetics model was found to correlate the experimental data well.

This study is removal of fluoride ion from aqueous solution by nano zero valent iron (nZVI). Effects of the factor variables (temperature, nZVI dose and pH) and their interactions on adsorption of fluoride ion were investigated by response surface methodology (RSM) based on Box-Behnken design (BBD). Optimized values of temperature, nZVI dose and pH for fluoride sorption were found as 313K, 0.5 g, and 4, respectively. The effect of initial fluoride concentration on the adsorption amount was investigated by a batch experiment. For study the fluoride removal mechanism, various adsorption isotherms such as Langmuir, Freundlich and Temkin were fitted. The results showed that the Freundlich isotherm gave high fit for fluoride adsorption. The time of adsorption reaction was rapid and subordinated pseudo-second-order kinetics. The values of thermodynamic parameters indicated that adsorption was spontaneous and endothermic in nature. The nano zero valent iron (nZVI) could be used as a potential adsorbent for fluoride ion containing aqueous solution.

Removal thermodynamics and desorption studies of some heavy metal ions such as Co(II), Cu(II) and Pb(II) by polymeric surfaces such as poly 2-hydroxyethyl methacrylate (PHEMA) and copolymer 2-hydroxyethyl methacrylate with monomer methyl methacrylate P(MMA-HEMA) as adsorbent surfaces from aqueous single solution were investigated with respect to the changes in pH of solution, adsorbent composition, contact time and temperature in the individual aqueous solution. The linear correlation coefficients of Langmuir and Freundlich isotherms were obtained and the results revealed that the Langmuir isotherm fitted the experiment results better than Freundlich isotherm. Using the Langmuir model equation, the monolayer removal capacity of PHEMA surface was found to be 0.7388, 0.8396 and 3.0367 mg/g for Co(II), Cu(ΙΙ) and Pb(II) ions and removal capacity of P(MMA-HEMA) was found to be 28.8442, 31.1526 and 31.4465 mg/g for Co(II), Cu(ΙΙ) and Pb(II) ions, respectively. Changes in the standard Gibbs free energy (ΔG0), standard enthalpy (ΔH0) and standard entropy (ΔS0) showed that the removals of mentioned ions onto PHEMA and P(MMA-HEMA) are spontaneous and exothermic at 293-323 K. The maximum desorption efficiency was 75.26% for Pb(II) using 0.100 M HNO3, 70.10% for Cu(II) using 0.100 M HCl, 59.20% for 0.100 M HCl 63.67% Co(II).

We present a case of a 70-year-old woman with severe peripheral arterial disease presenting with celiac artery in-stent thrombosis diagnosed by transesophageal echocardiography (TEE). Routine assessment of the visceral arteries is not performed in most TEE studies. A review of the literature shows that the celiac and superior mesenteric arteries can be successfully visualized during transgastric views of the abdominal aorta. We propose that two-dimensional and color Doppler echocardiography have several intrinsic advantages over computed tomography, magnetic resonance angiography and catheterization when assessing aortic and visceral arterial pathology.

Extramedullary plasmacytoma is rare in patients with diagnosed multiple myeloma. Soft tissue plasmacytoma of the gallbladder is particularly uncommon and has been described in only a handful of cases. Diagnosis of gallbladder plasmacytoma with fluorine 18-fluorodeoxyglucose (F18-FDG) positron emission tomography/computed tomography (PET/CT) has not previously been reported. We present a 65-year-old female with a history of multiple myeloma who underwent a restaging F18-FDG-PET/CT which showed a focal area of hypermetabolic activity, corresponding to a nodular lesion within the posterior gallbladder wall. The patient underwent successful cholecystectomy, with surgical pathology revealing gallbladder plasmacytoma. A follow-up scan was negative for active malignancy. This is a novel case of gallbladder plasmacytoma diagnosed on whole-body F18-FDG PET/CT – thus demonstrating the clinical value of this imaging modality in staging, restaging, and surveillance for patients with multiple myeloma.

Nitrogen and phosphorus compounds are very essentialelements for living organisms.However, when they aremore than needed, they can lead to eutrophication.The main purpose of this work is to kinetics study the possibilities for removal of ammonium ions from aqueous solutions by using multi-walled carbon nanotube (MWCNTs).The equilibrium time was found to be 35 min. Removal of ammonium ions was investigated using solutions with different concentrations in the range 100–140 mg/L. In this study adsorption of ammonium ions on multi-walled carbon nanotube surface has been investigated by UV-Vis spectrophotometer. The microstructure of carbon nanotubes were characterized using scanning electron microscopy (SEM).The kinetic rates were modeled by using the pseudo-first-order, pseudo-second-order, Intraparticle diffusion andElovich models. The pseudo-second-order model was found to explain the adsorption kinetics mosteffectively. It was also found that the pore diffusion played an important role in the ads...

This article has been withdrawn at the request of the author(s) and/or editor. The Editor apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at http://www.elsevier.com/locate/withdrawalpolicy .