•This paper explores imperfect demand-return correlation in closed-loop supply chains.•We measure inventory performance and production smoothing in both flows of materials.•Correlated returns improve ...performance, independent returns are detrimental.•We suggest and compare two control structures for the recoverable inventory.•Parallel return inventory control policy outperforms the alternative and the push policy.
Several studies have determined that product returns positively impact on the dynamics of hybrid manufacturing-remanufacturing systems, provided that they are perfectly correlated with demand. By considering imperfect correlation, we observe that intrinsic variations of returns may dramatically deteriorate the operational performance of these closed-loop supply chains. To cope with such added complexity, we propose a structure for controlling the reverse flow through the recoverable stock. The developed mechanism, in the form of a prefilter, is designed to leverage the known positive consequences of the deterministic component of the returns and to buffer the harmful impact of their stochastic component. We show that this outperforms both the benchmark push system and a baseline solution consisting of regulating all the returns. Consequently, we demonstrate that the operation of the production system is greatly smoothed and inventory is better managed. By developing a new framework for measuring the dynamics of closed-loop supply chains, we show that a significant reduction in the net stock, manufacturing, and remanufacturing variances can be achieved, which undoubtedly has implications both for stock reduction and production stabilization. Thus, the known benefits of circular economy models are strengthened, both economically and environmentally.
The site-specific management is the technology that considers the natural variability within the same field of factors related to crop growth to improve its management practices such that the ...agricultural treatments are varied for field's small production zones saving resources and environment, and improving crop quality and size. Since site-specific decisions are not far from the Fourth Industrial Revolution and the concept of processes automation, this work addresses improving the process of spatial variability analysis and thus supporting management decisions by developing a system-entitled EGYPADS-based on the Internet of Things and its enabling technologies. EGYPADS automates data collection, zones delineation according to their land suitability evaluation, and maps generation. The paper addresses a case study of potato crop in a specific area in Egypt, El-Salhia, in which eighty-five sites were chosen as main dataset for the modeling process during different stages of crop growth. Three management zones were recognized of the selected field based on the differentiation in their land suitability characteristics, representing about 5%, 65%, and 30% of the total area, respectively. The structure, screens, and services of EGYPADS are described in this paper. EGYPADS offered services include: management zones delineation using absolute and virtual coordinates, Land Suitability Assessment (LSA), data entry from field in real-time as well as from excel sheets, saving maps in suitable format for variable rate application, real-time and historical data processing, centralized management, and flexible formulation of events and related actions. The implementation of EGYPADS was verified. The system dynamically produces non-contiguous isobands, each representing a specific range of parameter values, and can be properly exported for use by other programs or smart machinery. It was proven that EGYPADS supports more than one land with different geometry, area, location, and number of nodes. EGYPADS was compared with the traditional LSA method, and was found to produce similar management zones.
Background
Cystic fibrosis (CF) is an autosomal recessive disease. It affects multiple organ systems, including the liver, leading to CF‐related liver disease (CFLD). It was noted that CFLD in ...Egyptian children with CF is more common than in non‐Egyptian people with CF (pwCF). This study aimed to determine the incidence of CFLD and the potential risk factors for developing CFLD in Egyptian children. The correlation between CFLD and the various genotypes prevalent in Egyptian CF children will be discussed. In addition, comparison of CFLD in Egyptian and non‐Egyptian CF patients will be presented.
Methods
This cross‐sectional study included 50 pwCF from Ain Sham University's Pediatric Pulmonology Clinic in Children's Hospital, Cairo, Egypt. The sweat chloride test and genetic studies were done at the time of diagnosis. Additionally, all subjects underwent detailed history taking, laboratory investigations, clinical assessment, and pelvic abdominal ultrasound for evaluation of hepatic involvement.
Results
One‐third of the Egyptian children with CF were found to have liver disease. The following independent risk factors for developing CFLD were identified as: male sex, severe genetic mutation (class I and II), long duration of CF disease, early onset of the CF, pancreatic insufficiency, as well as history of meconium ileus. In addition, diabetes mellitus and severe lung disease were proven to significantly increase the risk of developing CFLD.
Conclusion
CFLD is common in Egyptian pwCF. CFLD's risk factors are similar to other reported research from other countries in the region.
The d0 ferromagnetism through hole induction can be realized in oxide perovskites. The electronic and magnetic properties of AZrO3 (A = K, Rb, and Cs) cubic perovskites have been computationally ...analyzed using generalized gradient approximation (GGA) and modified Becke-Johnson (mBJ) potentials. From the evaluation of tolerance factor, volume optimization, formation energy, and phonon dispersion, their structural, magnetic, and dynamical stabilities in the ferromagnetic cubic phase have been verified. Additionally, Blackman's and Every's diagrams ensure their elastic stability without any symmetry-breaking phase transitions. The three-dimensional surfaces of elastic moduli and acoustic wave velocities indicate the degree of anisotropy in these perovskites. The compounds become more ductile for larger alkali cations. The band structures from both functionals confirm that the localized magnetic moments around oxygen atoms arise only from the exchange spin splitting of O-2p orbitals. The integer magnetic moment of 1 μB and complete spin polarization implies the presence of half-metallic ferromagnetism. Among the proposed compounds, the predicted mean-field curie temperature of CsZrO3 is above room temperature and may serve as optimal magnetic layers in spin-valve sensors and magnetic tunnel junctions.
This research investigates a new coordination strategy for both isolated single-area and interconnected multi-area microgrids (MGs) using a modified virtual rotor-based derivative technique supported ...with Jaya optimizer based on balloon effect modulation (BE). Accordingly, the main concept of BE is to assist the classic Jaya to be more sensitive and trackable in the event of disturbances, as well as to provide optimum integral gain value on the secondary frequency controller adaptively for both suggested MGs. The proposed modified virtual rotor mechanism is consisting of virtual inertia and virtual damping that are added as a tertiary controller within proposed MGs considering full participation of the inverter-based energy storage systems. The proposed virtual rotor mechanism is consisting of virtual inertia and virtual damping that are added as a tertiary controller within proposed MGs to emulate the reduction in system inertia and the enhanced damping properties. Several nonlinearities were proposed in this work such as a dead band of governor, generation rate constraints, and communication time-delay are considered within the dynamic model of the suggested MGs. In addition, the proposed design of multi-area MGs takes the interval time-varying communication delays into account for stability conditions. In this study, A comparative study using unimodal (i.e., Sphere) and multimodal (i.e., Rastrigin) benchmark test functions are conducted to validate the proposed direct adaptive Jaya-based BE. Furthermore, Wilcoxon's rank-signed non-parametric statistical test using a pairwise comparison was performed at a 5 % risk level to judge whether the proposed algorithm output varies from those of the other algorithms in a statistically significant manner. Thence, the superiority and effectiveness of the proposed method have also been verified against a variety of other metaheuristics optimization techniques, including classic electro-search, particle swarm, multi-objective seagull, and Jaya optimizers. In addition, an operative performance is assessed against the conventional integral controller, coefficient diagram method, and classic Jaya with/without virtual inertia. The final findings emphasize the superiority of the proposed direct adaptive Jaya-based BE supported by a modified virtual rotor and state better performance and stability compared to existing controllers.
The Acrylamide is a toxic compound generated under oxidative stress arising from intracellular ROS production and induced toxicity. It is frequently used in industry and generated through the heating ...of tobacco and foods high in carbohydrates. The exact mechanism of its toxicity is still unclear. In this study, an extract of the peels of pomegranate (
L.), a nutritious and visually appealing fruit with a diverse bioactive profile, was examined for its potential anti-apoptotic, antioxidant, and anti-inflammatory effects. A total of 40 adult male Wistar rats were allocated into four groups of 10 rats each: Group 1 was a negative-control group (CNT) and received normal saline; Group 2 was a positive-control acrylamide group and received acrylamide orally at a dose of 20 mg/kg/bw; in Group 3, the rats were supplemented with pomegranate-peel extract (P.P; 150 mg/kg/bw) orally on a daily basis for 3 weeks, administered simultaneously with the acrylamide treatment described for Group 2; Group 4 was a protective group, and the animals received the pomegranate-peel extract and acrylamide as stated for Groups 2 and 3, with the pomegranate-peel extract (P.P. extract) administered 1 week earlier than the acrylamide. The results indicate that acrylamide exposure increased the serum levels of AST, ALT, creatinine, interleukin-1 beta, and interleukin-6 in an extraordinary manner. In addition, it increased the lipid peroxidation marker malondialdehyde (MDA) and simultaneously weakened antioxidant biomarker activities (SOD, GSH, and catalase) and reduced the levels of interleukin-10. The pomegranate-peel extract was shown to reduce the inflammatory blood markers of interleukin-1 beta and IL-6. Glutathione peroxidase, superoxide dismutase, catalase, and interleukin-10 were all significantly elevated in comparison to the acrylamide-treatment group as a result of the significant reduction in MDA levels induced by the P.P extract. In addition, the pomegranate-peel extract normalized the cyclooxygenase-2 (COX2), transforming growth factor-beta 1 (TGF-β1), and caspase-3 levels, with a significant upregulation of the mRNA expression of heme oxygenase-1 (HO-1), nuclear factor erythroid 2 (Nrf2), and Bcl-2. Therefore, these data reveal that pomegranate peel has anti-inflammatory, antiapoptotic, free-radical-scavenging, and powerful antioxidant activity that protects against acrylamide toxicity.
By using DFT simulations employing the GGA/PBE and LDA/CA-PZ approximations, the effects of the Hubbard U correction on the crystal structure, electronic properties, and chemical bands of the cubic ...phase (Pm3¯m) of STO were investigated. Our findings showed that the cubic phase (Pm3¯m) STO’s band gaps and lattice parameters/volume are in reasonably good accordance with the experimental data, supporting the accuracy of our model. By applying the DFT + U method, we were able to obtain band gaps that were in reasonably good agreement with the most widely used experimental band gaps of the cubic (Pm3¯m) phase of STO, which are 3.20 eV, 3.24 eV, and 3.25 eV. This proves that the Hubbard U correction can overcome the underestimation of the band gaps induced by both GGA/PBE and LDA/CA-PZ approximations. On the other hand, the Sr-O and Ti-O bindings appear predominantly ionic and covalent, respectively, based on the effective valence charges, electron density distribution, and partial density of states analyses. In an attempt to enhance the performance of STO for new applications, these results might also be utilized as theoretical guidance, benefitting from our precise predicted values of the gap energies of the cubic phase (Pm3¯m).
Acute kidney injury is a common problem in dogs and is associated with significant morbidity and mortality. So, the present study aimed to evaluate symmetric dimethylarginine (SDMA) and Doppler ...ultrasonography including resistive index (RI) in the diagnosis of acute kidney injury in dogs. Ten healthy mongrel dogs were injected with gentamicin sulfate 10% at the dose of 30 mg/kg body weight daily for 10 days for induction of acute kidney injury. Clinical, biochemical, ultrasonographic, and Doppler ultrasonographic examinations and urinalysis were performed for all dogs on 0 day before induction, on the 5th day, and on the 10th day of induction. The results of the current study showed significant increase in plasma level of SDMA, serum urea, creatinine, phosphorus, and potassium and a significant decrease in serum sodium, calcium, and chloride on the 5th day and 10th day of induction, and there was an increase in renal cortical echogenicity of the right and left kidney compared to adjacent liver and spleen, respectively. RI value showed a significant increase on the 5th day and 10th day of induction. The present study showed that SDMA is a sensitive and promising biomarker for diagnosis of acute kidney injury in dogs compared to routine biomarkers; also, the RI of Doppler ultrasonography is useful for early identifying acute kidney injury when the only observable change is an increase in cortical echogenicity.
Microwave-assisted, facile, fast and one pot method is reported for synthesis of ternary hybrids material containing manganese cobaltite (MnCo2O4) nanoparticles (MCO NPs) wrapped by microwave ...exfoliated-reduced graphene oxide nanosheets (ME-rGO NSs) for improved supercapacitor electrode materials. In synthesized ME-rGO NSs wrapped MCO NPs (GW-MCO) ternary hybrids material, MCO NPs are completely wrapped by ME-rGO NSs and provides a conductive scaffold constructed from wrinkled ME-rGO NSs. Owning to this unique GW-MCO ternary hybrids formation, the used ME-rGO NSs possesses high surface area (391.76 m2/g) with suitable pore size distribution, which can effectively accommodate the electrolyte ions migration inside hybrids. The interconnected GW-MCO ternary hybrids conducting network, as an adhesive, can maintain structural stability and promote charge transport by encapsulating agglomerated nanosized MCO NPs. The structural and morphological studies of synthesized GW-MCO ternary hybrids was characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), transmission electron microscopy (TEM), Raman spectra, thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS) and Brunauer-Emmett-Teller (BET) surface area. Moreover, the GW-MCO ternary hybrids based electrode for supercapacitor delivers a high specific capacitance of 562 F/g (20 mV/s) and excellent long-term cycle stability (remain 92.3% after 2000 cycles). This study provides a new, simple and fast approach to wrap different kind of metal oxide NPs by ME-rGO NSs to fabricate electrode material for high performance supercapacitor.
Shipping is a significant contributor to global greenhouse gas (GHG) and air pollutant emissions. These emissions mainly come from using diesel fuel for power generation. In this paper, the natural ...gas is proposed as an alternative marine fuel to be used instead of conventional marine diesel oil. Numerical analysis of environmental and economic benefits of the natural gas-diesel dual-fuel engine is carried out. As a case study, a container ship of class A7 owned by Hapag-Lloyd has been investigated. The results show that the proposed dual-fuel engine achieves environmental benefits for reducing carbon dioxide (CO
2
), nitrogen oxides (NOx), sulfur oxides (SOx), particulate matter (PM), and carbon monoxide (CO) emissions by 20.1%, 85.5%, 98%, 99%, and 55.7% with cost effectiveness of 109, 840, 9864, 27761, and 4307 US$/ton, respectively. The results show that the conversion process to the dual-fuel engine will comply with the current and future IMO regulations regarding air pollutant emissions. On the other hand, using the proposed dual-fuel engine on the container ship will improve the ship energy efficiency index by 29.6 % with annual fuel cost saving of 4.77 million US dollars.
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