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Purpose Antimicrobial resistance is a major concern that we are facing nowadays. This is due to antibiotic misuse and bacteria developing resistance to the commonly used antibiotics. This may lead to increased mortality and consumption of country resources. Implementation of an antimicrobial stewardship program [ASP] can limit the use of unnecessary antibiotics and subsequently decrease the infection rates with better patient outcome. We aimed to control antibiotic misuse, reduce infection rate, decrease drug costs, and reduce length of hospital stay in the ICU. Methods We conducted a prospective study on the surgical neonatal ICU [SNICU] over a period of 6 months divided into pre-implementation phase, followed by an ASP phase, in which we applied the antibiotic guidelines approved by the ASP committee. Data were collected in the two phases and analyzed for demographics, compliance with guidelines, prescribed antibiotics, lab investigations, surgical site infection [SSI], length of stay and patient outcome. Results Compliance to the guidelines was encountered in 86% and SSI rate decreased to 20%. Days of Therapy (DOT) per 1000 patient days showed a significant decrease in Ampicillin Sulbactam by 296 (p = 0.024), Imipenem by 220.34 (p = 0.024) and Vancomycin by 287.34 (p = 0.048). Drug cost showed a 1185.97 EGP decrease in the ASP period compared to the pre-implementation period (p = 0.714). Average LOS decreased in the ASP period by a mean difference of 2.5 (p = 0.027). Conclusion ASP implementation can control antibiotic misuse, decrease the medical care expenses and improve patient outcome. Type of study Clinical research paper. Level of evidence Level one.

The continuous increase in the level of greenhouse gas (GHG) emissions and the increase in fuel prices are the main driving force to utilize various source of renewable energy. Among the clean energy technologies, solar energy is recognized as one of the most promising choice since it is free and provides clean and environmentally friendly energy. The objective of this paper is to improve the heating capabilities of evacuated tubes solar cookers that operates based on a closed loop thermosyphon action, and utilize thermal oil as the heating medium. Two identical evacuated tube solar cookers have been designed and built to study the influence of inserting metallic wires or nanographene particles on the thermal performance of the cooker. Also, the study was based on the thermal transfer of natural convection of the thermal oil movement within the evacuated tubes. The metallic wires and the nanographene particles are inserted inside the evacuated tube, which is filled with the heat exchange oil. One cooker is always tested without any modifications, i.e. taken as a reference point. The other cooker is the developed cooker, i.e. with wires or particles. Steel, aluminum and copper wires have been examined, and the number of wires has been varied between 5, 10 and 15. It has been found that the copper wires improve the rate of heat transfer compared with steel wires, aluminum wires and the nanographene particles. It has been also obtained that there is a critical number of wires, i.e. 10 wires, above that the rate of heat transfer by natural convection decreases and this is due to the increased friction which resists the natural convection currents. Finally, adding nanographene particles increases the viscosity of the oil, which increases the resistance to natural convection currents and consequently decreases the rate of heat transfer by natural convection.

Al/ZnO: Al heterojunction was fabricated by depositing ZnO: Al film on Al substrate by spray pyrolysis technique at 220 °C substrate temperature. XRD, SEM and EDAX techniques were used to study the properties of thin films. Heterojunction properties were studied by I–V and C–V measurements. The fabricated Al/ZnO: Al junctions were rectifying in character. The room temperature ideality factors of Al/ZnO: Al junctions are found to vary from 2.56 to 5.45. The reverse saturation currents are 5.21 × 10−9, 1.35 × 10−6, 1.99 × 10−6, 9.99 × 10−7 and 1.02 × 10−7 A for Al/ZnO: Al junctions. Junction forward current depends on doping concentrations and temperature, whereas reverse saturation current remains independent for Al concentration. The built-in-potential calculated from capacitance for Al/ZnO: Al junctions are 2.74, 2.60, 2.0, 2.50 and 2.43 V corresponding to 1, 2, 3, 4 and 5 mol% of Al. X-ray diffraction study confirmed that the films are polycrystalline, orientated in (0 0 2) plane. Scanning electron microscopy study confirmed circular ring patterns with inside ribbon type structure for Al doped ZnO films.

Experimental and numerical investigation of the triple concentric-tube heat exchanger with inserted ribs has been carried out. The purpose is to evaluate the performance characteristics of the triple tube heat exchanger with rib inserts. The investigation key design parameters involve water mass flow rate, flow pattern, temperature variation, rib height and rib pitch. Numerical CFD modeling is developed using FLUENT commercial code and validation criteria is done to extend the study parameters with extra ranges. The results revealed that, the insertion of ribs to the inner annulus fluid flow of the triple tube heat exchanger participate a significant enhancement of the convective heat transfer. Higher performance index is obtained at higher rib pitch and lower rib height. A set of empirical expressions with the dimensionless design parameters have been predicted based on the obtained data.

The experimental and numerical investigations of the triple concentric-tube heat exchanger are presented with particular reference to double tube heat exchanger. The purpose is to present a clear view on the thermo-fluid characteristics of this type of heat exchangers with different key design parameters leading to design optimization. Three fluids being considered are chilled water in inner tube, hot water in inner annulus, and normal tap water in outer annulus. Numerical CFD model is developed using a finite volume discretization method. The numerical model is validated and then extended to cover more extra design parameters. Four flow patterns are conducted of counter current, co-current, counter current with co-current and co-current with counter current flow. Correlations of Nusselt number, friction factor and heat exchanger effectiveness with the dimensionless design parameters are also presented. The triple tube heat exchanger contributes higher heat exchanger effectiveness and more energy saving compared with double tube heat exchanger per unit length.

In this work, an experimental study on energy saving for air conditioning application has been conducted. Heat Pipe Heat Exchanger (HPHX) was installed between the fresh air and return air streams to cool the fresh air before entering the air handing unit. Three test sections of wickless HPHX of different pipe diameters were tested. The studied test section inner diameters were 7.9, 10.2 and 16.56 mm. The study was conducted at different fresh air inlet temperatures to check the effect of ambient temperature on fresh air cooling. The mass flow rate ratio between return and fresh air was chosen to be 1, 1.5, 2 and 3. The obtained results indicated that the effectiveness of HPHX, the ratio of actual rate of heat transfer by HPHX to the maximum possible heat transfer rate between the two air streams, increases with the increase of fresh air inlet temperature, the ratio between return and fresh air mass flow rate, and heat pipe diameter. An energy reduction of about 30% was resulted due to inserting a wickless HPHX in the system with inner diameter 10.2 mm, average fresh air inlet temperature 35 °C and equal masses of fresh and return air streams. Economic analysis showed that the energy-saving decreases electrical consumption cost with a payback period of about three years with lifetime about 20 years.

In this study, accurate and convenient prediction models of tubular solar still performance, expressed as hourly production, were developed by utilizing machine learning. Based on experimental data, the models were developed and compared, such as classical artificial neural network with/without Baysian optimization, random forest with/without Baysian optimization, and traditional multilinear regression. Before applying Bayesian optimization, both random forest and artificial neural network predict hourly production. But the superiority of random forest is well behaved with insignificant error. The prediction performance of random forest, artificial neural network and multilinear regression were calculated as 0.9758, 0.9614, 0.9267 for determination coefficients, and 5.21%, 7.697%, 10.911% for mean absolute percentage error, respectively. Additionally, when applying Bayesian optimization for searching most appropriate hyper parameters, the performance of artificial neural network was significantly improved by 35%. Moreover, optimization findings revealed that random forest was less sensitive to hyper parameters than artificial neural network. Based on the robustness performance and high accuracy, the random forest is recommended in predicting production of tubular solar still.

Deposits of salts and extraneous materials occur during water desalination by heating, forming an insulating layer, which is known as fouling. Fouling reduces the rate of heat transfer between the heating medium and the water, subsequently decreases the desalination efficiency gradually and sometimes can lead to operation failure. The thermal shock is a fouling mitigation technique in water desalination units, which could be due to sudden decrease or increase in the heat transfer process. The objective of this research is to study the removal of fouling layers by the thermal shock in case of (i) smooth tubes, (ii) rough tubes and (iii) finned-rough tubes. It has been found that it is possible to remove the fouling layer by the thermal shock technique in case of smooth and rough tubes, but not in case of finned tubes. The thermal shock blows off the fouling layer in case of plain tubes, and the fouling process resumes after the thermal shock without any delays, i.e. no more induction period. Fins assist the sticking of crystals to the heat exchanger tubes and prevent its removal by thermal shock. Fins act as a heat sink during the thermal shock, which reduces the dissipation of heat to the surrounding water, i.e. cooling of the tubes, and prevent cracking of the fouling layer.

This work focused on the fabrication of p-type ZnO material by Ag–N co-doping using spray pyrolysis technique and the characterization of structural, surface morphology and opto-electrical properties. Hall measurements reveal that Ag–N co-doped ZnO thin films are p-type materials and highest mobility is obtained for 2.5 mol% of Ag doping, keeping the concentration of N unchanged. The resistivity of the films depends on doping level and shows a minimum value (ρ ~ 1.59 Ω-cm) with a carrier concentration of 4.09 × 10 16 cm − 3 for 2.5 mol% of Ag doping at the deposition temperature of 400 °C. X-ray diffraction study shows a single phase of ZnO up to 2.5 mol% of Ag doping level and after that a phase of silver oxide arises, which confirms that 2.5 mol% of Ag doping level is the optimum condition. The aging effect does not affect the p-type characteristics of the Ag–N co-doped ZnO films.

The nano-structural Al-doped ZnO thin films of different morphologies deposited on glass substrate were successfully fabricated at substrate temperature of 350 °C by an inexpensive spray pyrolysis method. The structural, electrical, optical and photoluminescence properties were investigated. X-ray diffraction study revealed the crystalline wurtzite (hexagonal) structure of the films with nano-grains. Scanning electron microscopy (SEM) micrographs indicated the formation of a large variety of nano-structures during film growth. The spectral absorption of the films occurred at the absorption edge of ∼410 nm. In the present study, the optical band gap energy 3.28 eV of ZnO decreased gradually to 3.05 eV for 4 mol% of Al doping. The deep level activation energy decreased and carrier concentrations increased substantially with increasing doping. Exciting with the energy 3.543 eV (λ=350 nm), a narrow and a broad characteristic photoluminescence peaks that correspond to the near band edge (NBE) and deep level emissions (DLE), respectively emerged.

While conversion of stable renal transplant recipients (RTR) from calcineurin inhibitors (CNI) to sirolimus (SRL) is safe and effective, it is still under investigation for recent, high-risk cases. We studied the long-term effects of conversion of high-risk subjects maintained on a CNI, mycophenolate mofetil, plus steroid regimen to SRL, mycophenolate mofetil, plus steroid on graft and patient outcomes. We retrospectively reviewed the first 100 RTR converted to SRL treatment over approximately 5 years. The main indications for conversion were biopsy-proven acute rejection (BPAR), CNI toxicity, CNI elimination, and acute-tubular necrosis (ATN). Exclusion criteria were limited to bone marrow suppression. The overall mean +/- SD age was 38.5 +/- 15.6 years, including pediatric and geriatric age groups. Mean +/- SD body mass index (BMI) was 28.99 +/- 8.0 and 40% had a BMI30. There were 40% RTR from deceased donors and 60% showed 4 to 6 HLA mismatches. Preconversion total BPAR and steroid-resistant rejection incidences were 35% and 14%, respectively. Mean +/- SD time to start of SRL was 11.9 +/- 22.8 months posttransplantation. Proteinuria2 g/d, leukopenia, and hyperlipidemia increased significantly after conversion (P = .001, P = .0003, and P = .0001, respectively). Patient and graft survivals were 95% and 90%, respectively. There was significant improvement in graft function postconversion (P.0001). There was a high incidence of side effects and cases of SRL discontinuation. Multivariate analysis demonstrated the influence of bone marrow suppression, obesity, hyperlipidemia, nutritional status, proteinuria, and graft function on graft and patient outcomes. We concluded that conversion from CNI to SRL was effective among high-risk RTR, but with a high incidence of adverse events during long-term follow-up.

Introduction Invasive fungal sinusitis is a rare but often fatal infection in immunocompromised patients. Aggressive antifungal treatment is mandatory, but is not without risk. Caspofungin, an antifungal agent that is a member of the echinocandin family, an inhibitor of glucan synthesis in the fungal wall, is active against Aspergillus and Candidae infections. Although it works on the fungal wall, it does not affect mammalian cells; hence, its toxicity is minimal. Case Summary This report describes a case of invasive Aspergillus sinusitis in a kidney transplant recipient with diabetes mellitus. The infection involved the apex of the right orbit causing optic nerve compression. The patient was treated with transnasal endoscopic decompression of the optic nerve and intravenous AmBisome (liposomal amphotericin B) for 2 weeks without clinical improvement. The combination of caspofungin and AmBisome administered for another 2 weeks yielded partial improvement. The AmBisome had to be discontinued due to deterioration of renal and hepatic function, but the patient completed a further 7-week course of caspofungin alone. Retro-orbital biopsy confirmed a complete response to treatment; the patient’s renal and hepatic function returned to normal. Conclusion This case indicates that caspofungin is effective to treat invasive Aspergillus sinusitis in kidney transplant recipients. This agent is well tolerated and safe with respect to renal and hepatic function.

Objective. The area under the concentration-time curve of cyclosporine microemulsion is the best measure of the absorption and beneficial effects in renal transplant recipients. We sought to determine the best method of monitoring cyclosporine levels in these patients. Methods. Prospective evaluation of peak cyclosporine blood levels and area under the curve monitoring were performed for 1 year in 65 renal transplant recipients (study group). Cyclosporine trough levels and peak cyclosporine blood levels were correlated with the calculated area under the curve. Cyclosporine trough levels were monitored in equal numbers of matched controls. Results. There were no significant differences in the incidence of acute rejection, cyclosporine nephrotoxicity, proteinuria, serum creatinine levels, or graft and patient outcomes between the groups (P = .1). Peak cyclosporine blood levels guided by calculating the area under the curve were found to be 27% to 32% lower than previously reported. The correlation coefficient was 90% for peak cyclosporine blood levels (P

Background Renal allograft transplantation with multiple arteries (MRA) was always avoided as much as possible as it is technically demanding and carries a higher MSK for complications. This was a single-center study to explore the graft outcomes of kidney transplantation with MRA. Patients and Methods We retrospectively reviewed the medical records of 35 patients who received kidney grafts with MRA for the surgical technique, surgical complications, graft function, and graft survival. The results were compared with those achieved in recipients of kidney grafts with a single renal artery (SRA). Results Of 35 grafts, there were 2 renal arteries in 30 grafts, and 3 renal arteries in 5 grafts. In the MRA group, there were 7 instances of surgical complications, the mean serum creatinine levels were 122, 139, and 156 μmol/L at 1 month, 1 year, and 5 years, respectively, and the actuarial graft survival rates were 94.3%, 88.6%, and 83% at 1, 5, and 10 years, respectively. In the SRA group, there were 56 instances of surgical complications, the mean serum creatinine levels were 115, 121, and 141 μmol/L at 1 month, 1 year, and 5 years, respectively, and the actuarial graft survival rates were 93.7%, 88.1%, and 84.4% at 1, 5, and 10 years, respectively. Conclusion Although transplantation of MRA grafts might carry a relatively higher risk for complications, it is justified because it gives results comparable with those achieved in SRA.

The prevalence of inflammatory bowel disease (IBD) after renal transplantation is affected by the immune tolerance and the modality of immunosuppression. Mycophenolate mofetil (MMF) may have a promoting effect on the development of posttransplantation erosive enterocolitis and a Crohn's disease-like pattern of colitis. We have presented a 40-year-old man with end-stage renal disease due to chronic glomerulonephritis who commenced hemodialysis for 2 months before receipt of a live unrelated renal transplant. He developed early posttransplantation diabetes mellitus and an anti graft rejection episode, which responded to a methylprednisolone pulse and OKT3 treatment. His immunosuppressive regimen included prednisolone, MMF, and tacrolimus. Three years after transplantation, he developed mild constitutional symptoms, mouth ulcerations, and chronic intermittent bloody diarrhea. Colonoscopy showed active segmental colitis with aphthous ulcers, involving the proximal descending colon and the splenic flexure. Colonic biopsies showed distended and branched crypts in the ascending colon, moderate active chronic colitis with regenerative atypia, skipping appearance, and ulceration in the splenic flexure and descending colon. The edematous crypts were associated with ulcerations in the sigmoid colon and rectum. The features were highly suggestive of Crohn's disease. He was successfully treated with high-dose steroids and 5-aminosalicylic acid. Subsequently, he developed chronic transplant glomerulopathy and restarted hemodialysis. We concluded that de novo Crohn's disease may develop in renal transplant recipients despite immunosuppressive therapy especially with MMF immunosuppression.

Previous efforts in the simulation of crop-irrigation systems have been reviewed and carefully examined. A model based on the system dynamics approach of Forrester has been developed to assist farmers in determining the date and volume of water to apply to each field and the expected yields. The model effectively takes into account the feedback loops and non-linearity inherent in the real world system. The model has been based on a water balance of soil moisture, evapotranspiration, irrigation, precipitation and deep percolation, and the grain yield has been predicted. The validity of the model has been tested using experimental data of wheat grown in a lysimeter. The predicted soil moistures, cumulative evapotranspirations and grain yields were in good agreement with the actual observed values for different treatments of irrigation.