Summary Background Middle East respiratory syndrome coronavirus (MERS-CoV) infection is associated with high mortality and has no approved antiviral therapy. We aimed to compare ribavirin and ...interferon alfa-2a treatment for patients with severe MERS-CoV infection with a supportive therapy only. Methods In this retrospective cohort study, we included adults (aged ≥16 years) with laboratory-confirmed MERS-CoV infection and pneumonia needing ventilation support, diagnosed between Oct 23, 2012, and May 1, 2014, at the Prince Sultan Military Medical City (Riyadh, Saudi Arabia). All patients received appropriate supportive care and regular clinical and laboratory monitoring, but patients diagnosed after Sept 16, 2013, were also given oral ribavirin (dose based on calculated creatinine clearance, for 8–10 days) and subcutaneous pegylated interferon alfa-2a (180 μg per week for 2 weeks). The primary endpoint was 14-day and 28-day survival from the date of MERS-CoV infection diagnosis. We used χ2 and Fischer's exact test to analyse categorical variables and the t test to analyse continuous variables. Findings We analysed 20 patients who received ribavirin and interferon (treatment group; initiated a median of 3 days range 0–8 after diagnosis) and 24 who did not (comparator group). Baseline clinical and laboratory characteristics were similar between groups, apart from baseline absolute neutrophil count, which was significantly lower in the comparator group (5·88 × 109 /L SD 3·95 vs 9·88 × 109 /L 6·63; p=0·023). 14 (70%) of 20 patients in the treatment group had survived after 14 days, compared with seven (29%) of 24 in the comparator group (p=0·004). After 28 days, six (30%) of 20 and four (17%) of 24, respectively, had survived (p=0·054). Adverse effects were similar between groups, apart from reduction in haemoglobin, which was significantly greater in the treatment group than in the comparator group (4·32 g/L SD 2·47 vs 2·14 g/L 1·90; p=0·002). Interpretation In patients with severe MERS-CoV infection, ribavirin and interferon alfa-2a therapy is associated with significantly improved survival at 14 days, but not at 28 days. Further assessment in appropriately designed randomised trials is recommended. Funding None.
Single-point incremental forming (SPIF) is a technology that allows incremental manufacturing of complex parts from a flat sheet using simple tools; further, this technology is flexible and ...economical. Measuring the forming force using this technology helps in preventing failures, determining the optimal processes, and implementing on-line control. In this paper, an experimental study using SPIF is described. This study focuses on the influence of four different process parameters, namely, step size, tool diameter, sheet thickness, and feed rate, on the maximum forming force. For an efficient force predictive model based on an adaptive neuro-fuzzy inference system (ANFIS), an artificial neural network (ANN) and a regressions model were applied. The predicted forces exhibited relatively good agreement with the experimental results. The results indicate that the performance of the ANFIS model realizes the full potential of the ANN model.
A novel magnetically recoverable copper catalyst was successfully fabricated through the immobilization of Cu(NO
3
)
2
on the surface of silica-coated magnetic Fe
3
O
4
nanoparticles (Fe
3
O
4
@SiO
2
...) functionalized with S-benzylisothiourea ligand. The Fe
3
O
4
@SiO
2
-SMTU-Cu nanocomposite was fully characterized by FT-IR spectroscopy, SEM, EDX, TGA, XRD, VSM, ASS and ICP-OES techniques. The Fe
3
O
4
@SiO
2
-SMTU-Cu nanocomposite exhibited high catalytic activity in the synthesis of biologically active quinazolines and amides. According to our research on the literature, this is the first report in the use of magnetic copper nanocatalyst for the synthesis of quinazolines. In this paper, we also presented tentative mechanisms for the synthesis of quinazolines and amides in the presence of catalytic amount of Fe
3
O
4
@SiO
2
-SMTU-Cu nanocomposite. This method gives notable advantages such as easy separation of the catalyst by external magnetic field; excellent yields, short reaction times, nontoxic metal catalyst, and simplicity of operation make this method a facile tool for the synthesis of quinazolines and amides.
Fe
3
O
4
@SiO
2
-SMTU-Cu as a new and efficient nanomagnetic catalyst for the synthesis of quinazolines and amides.
Three organotin complexes containing furosemide as a ligand (L), Ph₃SnL, Me₂SnL₂ and Bu₂SnL₂, were synthesized and characterized. Octahedral geometry was proposed for the Me₂SnL₂ and Bu₂SnL₂, while ...the Ph₃SnL complex has trigonal bipyramid geometry. The synthesized organotin complexes (0.5% by weight) were used as additives to improve the photostability of poly(vinyl chloride), PVC, (40 μm thickness) upon irradiation. The changes imposed on functional groups, weight loss and viscosity average molecular weight of PVC films were monitored. The experimental results show that the rate of photodegradation was reduced in the presence of the organotin additives. The quantum yield of the chain scission was found to be low (9.8 × 10(-7)) when Ph₃SnL was used as a PVC photostabilizer compared to controlled PVC (5.18 × 10(-6)). In addition, the atomic force microscope images for the PVC films containing Ph₃SnL₂ after irradiation shows a smooth surface compared to the controlled films. The rate of PVC photostabilization was found to be highest for Ph₃SnL followed by Bu₂SnL₂ and Me₂SnL₂. It has been suggested that the organotin complexes could act as hydrogen chloride scavengers, ultraviolet absorbers, peroxide decomposers and/or radical scavengers.
AIMS: To evaluate the potential use of lemongrass essential oil vapour as an alternative for synthetic fungicides in controlling anthracnose of papaya. METHODS AND RESULTS: Lemongrass oil used in the ...study was characterized using gas chromatography‐flame ionization detection (GC‐FID) before it was tested against anthracnose of papaya in vitro and in vivo. The GC‐FID analysis showed that geranial (45·6%) and neral (34·3%) were the major components in lemongrass oil. In vitro study revealed that lemongrass oil vapour at all concentrations tested (33, 66, 132, 264 and 528 μl l⁻¹) suppressed the mycelial growth and conidial germination of Colletotrichum gloeosporioides. For the in vivo study, ‘Sekaki’ papaya were exposed to lemongrass oil fumigation (0, 7, 14, 28 μl l⁻¹) for 18 h and at room temperature for 9 days. Lemongrass oil vapour at the concentration of 28 μl l⁻¹was most effective against anthracnose of artificially inoculated papaya fruit while quality parameters of papaya were not significantly altered. CONCLUSIONS: This suggests that lemongrass oil vapour can control anthracnose disease development on papaya without affecting its natural ripening process. SIGNIFICANCE AND IMPACT OF THE STUDY: The potential practical application of this technology can reduce reliance on synthetic fungicides for the control of postharvest diseases in papaya.
This research demonstrates the utilization of newly designed advanced Ag/rGO/TiO2 ternary nanocomposite based photoanode for highly-efficient plasmonic dye-sensitized solar cells (PDSSCs). The ...Ag/rGO/TiO2 ternary nanocomposite was successfully synthesized by a facile solvothermal approach without deploying any hazardous agent. In order to achieve the higher power conversion efficiency of the PDSSCs, it was necessary to improve the electron injection rate and optical absorbance of the photoanodes. The nanocomposite was characterized by FE-SEM and TEM analyses, which disclosed that the ternary nanocomposite has been synthesized. The incorporation of Ag nanoparticles onto the TiO2 nanoparticles considerably improved the optical parameters because of the localized surface plasmon resonance (LSPR). XRD and EDX spectroscopic techniques were utilized to confirm the synthesis of Ag nanoparticles and rGO. Furthermore, thermal stability of the nanocomposite was investigated by thermal gravimetric analysis (TGA). Ag/rGO/TiO2 ternary nanocomposite based photoanode demonstrated an enhanced power change productivity of 6.87% in PDSSCs, which was 15% higher than that of the pure TiO2 nanoparticles based photoanode. In addition, an enhanced IPCE of 68% was also observed in comparison with the pure TiO2, which was found due to the remarkable conductivity of rGO.
•Newly designed advanced Ag/rGO/TiO2 ternary nanocomposite.•The Ag/rGO/TiO2 ternary nanocomposite was successfully synthesized by a facile solvothermal approach.•Ag/rGO/TiO2 ternary nanocomposite based photoanode demonstrated an enhanced power conversion efficiency of 6.87% in PDSSCs.
The studies about the effect of the graphene reinforcement ratio and machining parameters to improve the machining performance of Ti6Al4V alloy are still rare and incomplete to meet the Industry 4.0 ...manufacturing criteria. In this study, a hybrid adaptive neuro-fuzzy inference system (ANFIS) with a multi-objective particle swarm optimization method is developed to obtain the optimal combination of milling parameters and reinforcement ratio that lead to minimize the feed force, depth force, and surface roughness. For achieving this, Ti6Al4V matrix nanocomposites reinforced with 0 wt.%, 0.6 wt.%, and 1.2 wt.% graphene nanoplatelets (GNPs) are produced. Afterward, a full factorial approach was used to design experiments to investigate the effect of cutting speed, feed rate, and graphene nanoplatelets ratio on machining behaviour. After that, artificial intelligence based on ANFIS is used to develop prediction models as the fitness function of the multi-objective particle swarm optimization method. The experimental results showed that the developed models can obtain an accurate estimation of depth force, feed force, and surface roughness with a mean absolute percentage error of 3.87%, 8.56%, and 2.21%, respectively, as compared with experimentally measured outputs. In addition, the developed artificial intelligence models showed 361.24%, 35.05%, and 276.47% less errors for depth force, feed force, and surface roughness, respectively, as compared with the traditional mathematical models. The multi-objective optimization results from the new approach indicated that a cutting speed of 62 m/min, feed rate of 139 mm/min, and GNPs reinforcement ratio of 1.145 wt.% lead to the improved machining characteristics of GNPs reinforced Ti6Al4V matrix nanocomposites. Henceforth, the hybrid method as a novel artificial intelligent method can be used for optimizing the machining processes with complex relationships between the output responses.
To treat the stochastic wind nature, it is required to attain all available power from the wind energy conversion system (WECS). Therefore, several maximum power point tracking (MPPT) techniques are ...utilized. Among them, hill-climbing search (HCS) techniques are widely implemented owing to their various features. Regarding current HCS techniques, the rotor speed is mainly perturbed using predefined constants or objective functions, which makes the selection of step sizes a multifaceted task. These limitations are directly reflected in the overall dynamic WECS performance such as tracking speed, power fluctuations, and system efficiency. To deal with the challenges of the existing HCS techniques, this paper proposes a new adaptive HCS (AD-HCS) technique with self-adjustable step size using model reference adaptive control (MRAC) based on the PID controller. Firstly, the mechanical power fluctuations are detected, then the MRAC continuously optimizes the PID gains so as to generate an appropriate dynamic step size until harvesting the maximum power point (MPP) under the optimal tracking conditions. Looking specifically at the simulation results, the proposed AD-HCS technique exhibits low oscillations around the MPP and a small settling time. Moreover, WECS efficiency is increased by 5% and 2% compared to the conventional and recent HCS techniques, respectively. Finally, the studied system is confirmed over a 1.5 MW, gird-tied, double-fed induction generator (DFIG) WECS using MATLAB/Simulink.
Laser-powder bed fusion (L-PBF) process is a family of modern technologies, in which functional, complex (3D) parts are formed by selectively melting the metallic powders layer-by-layer based on ...fusion. The machining of L-PBF parts for improving their quality is a difficult task. This is because different component orientations (L-PBF-layer orientations) produce different quality of machined surface even though the same cutting parameters are applied. In this paper, stainless steel grade SS 316L parts from L-PBF were subjected to the finishing (milling) process to study the effect of part orientations. Furthermore, an attempt is made to suppress the part orientation effect by changing the layer thickness (LT) of the parts during the L-PBF process. L-PBF parts were fabricated with four different layer thicknesses of 30, 60, 80 and 100 μm to see the effect of the LT on the finish milling process. The results showed that the layer thickness of 60 μm has significantly suppressed the part orientation effect as compared to the other three-layer thicknesses of 30, 80 and 100 μm. The milling results showed that the three-layer thickness including 30, 80 and 100 μm presented up to a 34% difference in surface roughness among different part orientations while using the same milling parameters. In contrast, the layer thickness of 60 μm showed uniform surface roughness for the three-part orientations having a variation of 5-17%. Similarly, the three-layer thicknesses 30, 80 and 100 μm showed up to a 25%, 34% and 56% difference of axial force (Fa), feed force (Ff) and radial force (Fr), respectively. On the other hand, the part produced with layer thickness 60 μm showed up to 11%, 25% and 28% difference in cutting force components F
, F
and F
, respectively. The three-layer thicknesses 30, 80 and 100 μm in micro-hardness were found to vary by up to 14.7% for the three-part orientation. Negligible micro-hardness differences of 1.7% were revealed by the parts with LT 60 μm across different part orientations as compared to 6.5-14% variations for the parts with layer thickness of 30, 80 and 100 μm. Moreover, the parts with LT 60 μm showed uniform and superior surface morphology and reduced edge chipping across all the part orientations. This study revealed that the effect of part orientation during milling becomes minimum and improved machined surface integrity is achieved if the L-PBF parts are fabricated with a layer thickness of 60 μm.
•New fluorescence turn on cyanide detection assay employs disposable paper based sensing platform and user friendly mobile application for quantification of cyanide in water.•It is described that the ...facilitation of quantitative detection of CN− by custom-made image processing algorithm to standardize the detection methodology which recognize color codes providing CN detection as low as 10−12M.•The new algorithm is applicable to ordinary smart phone equipped with camera and transforms these devices into a quantitative cyanide detector.
An organometallic dye, europium tetrakis dibenzoylmethide triethylammonium (EuD4TEA) and gold nanoparticles (Au NPs) impregnated paper based sensor platform have been utilized for development of fluorescence turn-on cyanide assay in aqueous media. The ordinary filter paper with 6μ m pore size were employed as solid support that facilitates impregnation of EuD4TEA and gold nanoparticles and provides durability. Detection mechanism relying on two processes (i) dissolution of gold nanoparticles causing fluorescence recovery and (ii) ligand exchange of triethyl amine with CN group stimulating cyanide specific fluorescence enhancement. The paper platform exhibit naked eye distinguishable color transition upon CN− addition from 10−2 to 10−12M. To standardize the methodology a homemade image processing algorithm has been developed that enabling calibration of color change and quantify CN− concentration. The described algorithm is applicable to Android smart phones and facilitate transforming these devices into a quantitative cyanide detector. The overall methodology provides instrument free cyanide detection and therefore rapid control of water quality and safety at off-field conditions.
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