Thermal evaporation technique has been used to fabricate a hybrid heterojunction Al/p-Si/CuPc/Au photodiode by deposition of a CuPc thin film onto a p-Si substrate. The dark
I
–
V
curves exhibit ...diode-like behavior. The impedance characteristics of the Al/p-Si/CuPc/Au hybrid heterojunction were examined using complex impedance spectroscopy. In the investigated device, the activation energies have been obtained from Arrhenius plotting of two relaxation processes. The Cole–Cole plot and the electrical conductivity were reported and showed that the heterostructure possesses a negative temperature coefficient of resistance. The excess minority carrier lifetimes, the diffusion coefficients and the mobilities of charge carriers at two interfaces were calculated and interpreted. From the impedance spectra analysis, the band profile of the studied device can be fully determined.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, SIK, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Continuum robots are complex structures that require sophisticated modeling and control methods to achieve accurate position and motion tracking along desired trajectories. They are highly coupled, ...nonlinear systems with multiple degrees of freedom that pose a significant challenge for conventional approaches. In this paper, we propose a system dynamic model based on the Euler-Lagrange formulation with the assumption of piecewise constant curvature (PCC), where we accounts for the elasticity and gravity effects of the continuum robot. We also develop and apply a particle swarm optimization (PSO) algorithm to optimize the parameters of our developed controllers: an inverse dynamic proportional integral derivative (PID) controller and an inverse dynamic fuzzy logic controller (FLC), where we use the integral time of absolute error (ITAE) as the objective function for the PSO algorithm. We validate our proposed model and optimized controllers through different designed trajectories, simulated using our developed unique animated MATLAB simulation. The results show that the PSO-PID controller improves the rise time, overshoot percentage, and settling time by 16.3%, 31.1%, and 64.9%, respectively, compared to the PID controller without PSO. The PSO-FLC controller shows the best performance among all controllers, with a settling time of 0.7 s and a rise time of 0.4 s, leading to the highest level of precision in trajectory tracking. The ITAE error for the PSO-FLC controller is 11.4% and 29.9% lower than that of the PSO-PID and FLC controllers, respectively.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Experimental study has been carried out to investigate performance parameters, emissions, cylinder pressure, exhaust gas temperature (
T
exhaust) and engine wall temperatures (
T
wall) for direct ...injection diesel engine. Tests were conducted for sunflower oil (S100) and 20% jojoba oil
+
80% pure diesel fuel (B20) in comparison to pure diesel fuel with different engine speeds. S100 and B20 were selected for the study because of its being widely used in Egypt and in the world. Also, series of tests are conducted at same previous conditions with different percentage of exhaust gas recirculation (EGR) from 0% to 12% of inlet mass of air fresh charge. Results indicate that S100 or B20 gives lower brake thermal efficiency (
η
B), brake power (BP), brake mean effective pressure (BMEP), and higher brake specific fuel consumption (BSFC) due to lower heating value compared to pure diesel fuel. S100 or B20 gives lower NO
X
concentration due to lower gas temperature. S100 or B20 gives higher
T
wall and
T
exhaust due to incomplete combustion inside engine cylinder. S100 or B20 gives higher CO and CO
2 concentrations due to higher carbon/hydrogen ratio. The position of maximum pressure (
P
max) change for pure diesel fuel is earlier than for S100 or B20. The results show that S100 or B20 are promising as alternative fuel for diesel engine. The utilization of vegetable oils does not require a significant modification of existing engines. This can be seen as the main advantage of vegetable oils. The main disadvantages of biodiesel fuels are high viscosity, drying with time, thickening in cold conditions, flow and atomization characteristics.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
We identified the near-full-genome sequence (29,908 nt, >99%) of Middle East respiratory syndrome coronavirus (MERS-CoV) from a nasal swab specimen from a dromedary camel in Egypt. We found that ...viruses genetically very similar to human MERS-CoV are infecting dromedaries beyond the Arabian Peninsula, where human MERS-CoV infections have not yet been detected.
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DOBA, IZUM, KILJ, NUK, ODKLJ, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Curcumin is a poorly water-soluble drug that is used for the treatment of inflammations, tumors, wound healing antioxidant and other diseases. In the current manuscript, it is successfully formulated ...into proniosome gels. The proniosomes are readily hydrated into niosomal formulations using warm water. Proniosomes were prepared using nonionic surfactants (tween 80, span 60) either solely or in combinations with cholesterol. The produced niosomal formulations were homogenous in size with vesicular sizes >343 and <1800 nm. The encapsulation efficiency percentage "EE%" of curcumin in niosomal formulations was different according to niosomal composition. It increased up to 99.74% in formulations of tween 80/Chol of 200 μmole/mL lipid concentration. Span 60/chol niosomes showed decreased curcumin EE%. Niosomal formulations showed increased SSTF and PC with enhancement ratios of more than 20-fold compared with curcumin suspension form. Kinetically, niosomes fitted to the Korsemeyer-Peppas model with non-Fickian transport according to their calculated n-values where curcumin suspension form showed Korsemeyer-Peppas kinetics with Fickian transport. Niosomal formulations deposited higher curcumin amounts in the skin compared with the suspension form. The best niosomal formulation (F9) was used for niosomal gel and emulgel fabrication. Finally, the anti-inflammatory activity of curcumin in various formulations was evaluated using a rat hind paw edema method and the % of swelling was 17.5% following 24 h in group treated with curcumin niosomal emulgel. In conclusion, this study suggests that the developed niosomal emulgel could significantly enhance the anti-inflammatory effect of curcumin and be an efficient carrier for the transdermal delivery of the drug.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Caffeine (Caf) is a natural central nervous system stimulant categorized by the US Food and Drug Administration as a safe drug and its maximal amount in soft drinks has been approximately determined ...to be lower than 200 mg L
−1
. It is the world's most extensively used legal and unregulated psychoactive medication. A simple, low cost, sensitive and selective electrochemical method for the detection of Caf was developed using zeolite (Zeo) mixed with multi-walled carbon nanotube (MWCNTs) to give a modified carbon paste electrode (CPE) in a surfactant improved medium with sodium dodecyl sulfate (ZMWCNTMCPE/SDS) and carrying out cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and square wave voltammetry (SWV) measurements. Scanning electron microscopy (SEM) was also used to characterize the surface. The influence of varying the concentration
versus
the anodic current of Caf gives two linear ranges, the first is from 1.0 × 10
−5
to 1.0 × 10
−4
mol L
−1
, with a correlation coefficient of 0.9878, and the second is from 1.0 × 10
−4
to 5.0 × 10
−4
mol L
−1
. The limits of detection and quantitation were found to be 7.5 × 10
−8
and 2.5 × 10
−7
mol L
−1
respectively. The results show that the new sensor can be used to quantify Caf in black tea, coffee,
Nescafé
, Pepsi cola, diluted energetic drink samples, in real samples and Panadol extra pharmaceutical tablets. Satisfactory recoveries for all of the samples were obtained between 99.51% and 102.19% with relative standard deviations of 1.7-5.1%.
Caffeine (Caf) is a natural central nervous system stimulant categorized by the US Food and Drug Administration as a safe drug and its maximal amount in soft drinks has been approximately determined to be lower than 200 mg L
−1
.
A newly competitive electrochemical sensor for nicotine (NIC) detection was successfully achieved. Nano-TiO2 with a carbon paste electrode (CPE) were used for the sensor construction, where Nano-TiO2 ...was considered as one of the richest and highly variable class of materials. The sensor showed electrocatalytic activity in both aqueous and micellar media toward the oxidation of NIC at Britton–Robinson (B–R) buffer solution (4×10−2M) of pH range (2.0–8.0) containing (1.0mM) sodium dodecylsulfate (SDS) using cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) techniques. Scanning electron microscope (SEM) and Energy Dispersive X-Ray Analysis (EDX) techniques were also used. The linear range of detection for NIC using the new Nano-TiO2 Modified Carbon Paste sensor (NTMCP) was detected using diffrential pulse voltammetry (DPV) technique and it was found between 2×10−6M and 5.4×10−4M with a detection limit of 1.34×10−8M. The obtained results clarified the simplicity, high sensitivity and selectivity of the new NTMCPE for nicotine determination in real cigarettes and urine samples.
•A newly competitive electrochemical modified sensor was done for nicotine determination.•TiO2-Nanoparticles Chemically deposited on a carbon paste electrode (CPE).•The detection limit is 1.34×10−8M.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
The use of potent fungal mixed cultures is a promising technique for the biodegradation of crude oil. Four isolates of fungi, namely, Alternaria alternata (AA-1), Aspergillus flavus (AF-3), ...Aspergillus terreus (AT-7), and Trichoderma harzianum (TH-5), were isolated from date palm soil in Saudi Arabia. The mixed fungal of the four isolates have a powerful tool for biodegradation up to 73.6% of crude oil (1%, w/v) in 14 days. The fungal consortium no. 15 containing the four isolates (1:1:1:1) performed significantly better as a biodegradation agent than other consortium in a variety of environmental factors containing crude oil concentration, incubation temperature, initial pH, biodegradation time and the salinity of the medium. The fungal consortium showed better performance in the biodegradation of normal alkanes (n-alkanes) than that of the polycyclic aromatic hydrocarbons (PAHs); the biodegradation efficiency of normal alkanes of the fungal consortium (67.1%) was clearly high than that of the PAHs (56.8%).
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•Electrochemical detection of Caf was achieved using CPE modified with Cobalt oxide nanoparticles.•The best performance of the sensor was obtained in the presence of SDS ...surfactant.•The sensor can be applied for real sample analysis with acceptable recoveries and no noticeable interference.•The proposed electrochemical sensor has a limit of detection of 0.16 μmol L–1.
Caffeine (Caf) is one of the most widespread compounds in food components, beverages and medicines, which drives us to find a simple, fast and convenient method for its determination. The promising Nano-Cobalt (II, III) oxide modified carbon paste (NCOMCP) sensor was fabricated and applied to the sensitive determination of Caf in both aqueous (0.01 mol L−1 H2SO4) and micellar media (0.5 mmol L−1 sodium dodecylsulfate, SDS). Surface characterization was performed utilizing scanning electron microscopy (SEM) and energy dispersive analysis of X-rays (EDX). The electrochemical behavior of Caf was studied by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and chronoamperometry (CA). From these experiments, the apparent diffusion coefficient (Dapp) and catalytic rate constant (kcat) were evaluated to be 4.2 × 10-5 cm2 s-1 and 1.92 × 103 mol−1 L-2 s-1, respectively. Caf can be detected in a concentration range between 5.0 and 600 μmol L−1, with a limit of detection (LOD) of 0.016 μmol L−1, as determined from the calibration plot obtained using differential pulse voltammetry (DPV). The sensor was applicable for Caf sensing in several commercial real samples with recoveries ranging from 98.9% to 101.9%. It exhibited good selectivity in the presence of common interferences.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Sheep are considered one of the main sources of animal protein in Egypt and the producers of sheep mutton eagers to find biological criteria for selecting fast-growing lambs that reach market weight ...early. Therefore, the present study aimed to find a link between the expression profile of selected candidate genes with growth performance and carcass traits of Barki lambs. Thirty-eight Barki lambs were kept and fed individually after weaning till 12 months of age and were divided into 3 groups according to growth performance (fast, intermediate, and slow-growing). Three samples were taken from different body tissues (eye muscle, liver, and fat tail) of each group, directly during slaughtering and stored at − 80 °C until RNA isolation. Real-time PCR was used to profile selected candidate genes (RPL7, CTP1, FABP4, ADIPOQ, and CAPN3) and GAPDH was used as a housekeeping gene. The results indicated that the final body weight was significantly (
P
≤ 0.05) greater in the fast (49.9 kg) and intermediate (40.7 kg) compared to slow-growing animals (30.8 kg). The hot carcass weight was heavier (
P
≤ 0.05) in the fast and intermediate-growing (24.57 and 19.07 kg) than slow-growing lambs (15.10 kg). The blood profiles of T3 and T4 hormones in addition to other parameters such as total protein, total lipids, and calcium level showed no clear variations among different experimental groups. At the molecular level, our data demonstrated upregulation of genes involved in protein biosynthesis (RPL7), fatty acid oxidation (CPT1), and lipolysis (FABP4) in the fast and intermediate-growing lambs in all studied tissues which facilitate protein accretion, energy expenditure, and fatty acid partitioning required for muscle building up. Moreover, the expression profile of the gene involved in muscle development (CAPN3) was increased in fast and intermediate-growing compared to slow-growing lambs in order to support muscle proper development. On the other hand, a candidate gene involved in lipogenesis (ADIPOQ) was expressed similarly in fat and liver tissues; however, its expression was increased in muscles of fast and intermediate-growing lambs compared to slow-growing animals. In conclusion, the current study indicated that the expression profile of genes involved in metabolic activities of liver, muscle, and adipose tissue is linked with the growth performance of lambs although no variations were detected in blood parameters. This provides an evidence for the importance of co-expression of these genes in body tissues to determine the final body weight and carcass characteristics of Barki sheep.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
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