Search

Graphical Abstract:

Fast and accurate electrothermal characterization of superconducting fault current limiters (SFCLs) is critically important for their performance evaluation. At the design stage of the SFCL, simulation is needed to validate the feasibility of the idea before fabrication. The most popular simulation models are the finite-element models, thermal electrical analogy (TEA), equivalent circuit model, and the finite difference method. However, all those four models are time consuming either in preparing stage or in running stage. In this article, we propose an artificial-intelligence-driven model to achieve fast calculation and monitoring of SFCL. In this article, a surrogate model was presented to estimate the resistance and temperature of SFCL, under different fault scenarios. These scenarios include different fault duration, voltages, maximum prospective fault current, and different operating temperatures. The TEA was used to electrothermally simulate the SFCL under different fault scenarios. Then, temperatures of different layers in SFCL as well as the total resistance of SFCL were collected. Afterwards, a feed forward neural network (FFNN) was used for SFCL characterization. The data of fault scenarios were fed into FFNN as inputs while temperature and resistance were considered as outputs. Also, to show the superiority of FFNNs, two other intelligent methods were used for surrogate modeling of SFCL. Results showed that FFNN had more than 98% accuracy for estimating different electrothermal parameters of SFCL. This intelligent surrogate model is a step forward toward developing digital twin for SFCL in future cryo-electric aircraft.

Improving the quality and shelf life of wheat bread using controlled novel sourdoughs is a promising biotechnology process. In the present study, after molecular identification of the selected antifungal predominant lactic acid bacteria (LAB) isolated from fermented acorn, the isolate was used as starter culture to produce controlled fermented acorn (CFA). Then the characteristics of wheat bread containing non-fermented acorn, controlled and spontaneously fermented acorn were evaluated in terms of textural properties, antioxidant capacity, in situ antifungal activity and overall acceptability in comparison with the control. Sequencing results of the PCR products led to the identification of Pediococcus acidilacticias the selected antifungal LAB isolate. The effect of controlled fermentation on production of bioactive ingredients from acorn was also verified using GC/MS analysis. Crumb texture profile analysis revealed the significant effect (P< 0.05) of acorn substitution on crumb hardness, porosity and loaf specific volume. DPPH radical scavenging activity was remarkably increased after addition of CFA. Surface growth of A. flavuson wheat bread containing CFA was also significantly lower than the other samples. Sensory acceptance of the supplemented bread didn’t show significant difference with control. Accordingly, wheat bread enrichment with CFA, not only improve its quality and shelf life but also increase its safety and techno-functionality characteristics.

Municipal and industrial effluents contain metal ions that can cause diseases due to disturbances in the body’s metabolic and enzymatic processes. Given its simplicity and high efficiency, researchers have recently focused on adsorption using modified nanoadsorbents as one of the methods of removing heavy metals from effluents. In this study, a carbon nanostructure was first synthesized from common reed and modified with an amino acid. Based on screening in the Design Expert software, parameters affecting the adsorption process included pH, adsorbent dose, temperature, and contact time, respectively, which were optimized using the response surface methodology (RSM). The results showed that under optimal conditions, the maximum adsorption capacity was 126 mg lead per gram of adsorbent. Besides, the adsorption kinetic studies were performed using quasi-first-order and quasi-second-order models. The results showed that the quasi-second-order model, with a higher regression coefficient (R2= 0.9997), fit the experimental data better than the quasi-first-order model. The isothermal studies also indicated the good fit of the Langmuir model, with a coefficient of determination of 0.9996.

In the present study, composite filaments were produced by PLA with and without 1 wt% Mg particles. DSC results show that the presence of Mg reduces the crystallinity and increases the melting temperature. Extruded filaments were used to produce tensile samples by 3D printing. The mechanical properties of 3D printed samples were compared with monolithic and micro-sized samples. The monolithic samples show inferior strength and ductility compared to 3D-printed samples, which feature aligned polymer chains. The micro-sized samples show superior mechanical properties compared to the large samples by having fewer potential failure points. 3D-printed samples were also produced by various infill orientations (0o, 45o, ±45o, and 90o), and the samples were tested for biodegradation in SBF solution. The 0o, infill orientation presented the highest mechanical properties before and after the immersion test. The 90oinfill orientation samples were the most damaged samples by degradation. Microstructure studies show crevice corrosion is responsible for severe damage to the 90oinfill orientation samples. Mg in the crevice forms and locks a local alkaline environment, accelerating degradation.

Harmonic distortions—especially in current waveform—are the inherent nature of any power system, such as urban grids, wind farms, electric aircraft, and other electrified transportation units, that could change the ac loss value in high-temperature superconducting (HTS) cables. The aim is to investigate the impact of nonsinusoidal currents with different integer harmonics, interharmonics, and subharmonics on the ac loss characteristics of a 22.9 kV, 50 MVA HTS cable. This was accomplished by using an equivalent circuit model (ECM). To do so, current waveforms containing different harmonic components were passed to the ECM of HTS cable. For evaluating the impact of distorted current waveforms on the ac loss of the HTS cable, the ECM was validated by means of finite-element method (FEM) in tape level. The results of validation phase have shown good agreement between the ac loss value derived by ECM and those calculated by FEM published in the literature. The results showed that when current waveform was distorted by harmonics, the value of ac loss was changed significantly with respect to the variations of harmonic phase angle, order, and amplitude. Results also indicated that fifth harmonic order has the highest impact on the ac loss value and could increase 6%–80% of ac loss in comparison to pure sinusoidal current. Subharmonics and interharmonics could also increase the ac loss value to maximum 88% and 64% higher than that of sinusoidal condition.

Fault-tolerant current-limiting (FTCL) high-temperature superconducting (HTS) transformers are promising components for playing a role in renewable energy integrated modern power systems. In this article, the impact of different insulation materials and cryogenic coolant fluids on the electro-thermal characteristic of an MW-scale FTCL-HTS transformer is investigated. For this purpose, an equivalent circuit model (ECM) is established to characterize the temperature, recovery time, and fault tolerability of FTCL-HTS transformer under different conditions. The proposed ECM is firstly validated using experimental results of a typical HTS transformer. After that the model is developed for a 50 MVA, 132 kV/13.8 kV HTS transformer. In order to add fault tolerance capability to the 50 MVA HTS transformer, three strategies were considered in this article. In the first strategy, the effect of three insulation materials (including Kapton tapes, Nomex papers, and Acrylated Urethane solid insulation) covering HTS tapes was investigated on fault performance. The second strategy was changing cryogenic fluid to liquid hydrogen instead of liquid nitrogen. As for the last strategy, the impacts of thickness and material properties of stabilizer in HTS tape were investigated on the maximum temperature and recovery time of HTS transformer. Results show that by using these strategies, the maximum temperature of HTS tape of transformer winding under a short circuit fault was reduced.

In the present study nine successive ARB cycles were applied on double-layer 1 mm aluminum sheets following three different routes; normal, reverse and cross. Severely deformed sheets were studied by XRD and EBSD to show the evolution of crystallographic textures, while mechanical properties are characterized by micro-tensile and micro-hardness tests. Results indicate that changing the route significantly affects the formation of crystallographic texture components in the structure, leading to different macro mechanical properties. As the asymmetry increases in the strain route, the intensity of the texture components reduces by 57% from as-received structure to the most asymmetric ARBed sample, i.e., cross route. The difference is attributed to different activated slip system in each route. The higher the asymmetry of the route, the lesser the necessity for the cross-slip, and the more the dynamic recrystallization in the structure. Hence, the finest grains happen to form in Normal ARBed sample. The same mechanism is responsible for higher strength (36%) and hardness (32%) observed in Normal ARBed sample. However, the change of route also lowers the bond strength in Cross and Reverse ARBed samples, weakening them by almost 12% regarding the as-received sheet.

Based on the requirements of microgrids and Uninterruptible Power Supply systems, an MJ-class energy storage device is necessary to enhance the stability of microgrids during power interruptions and outages. This study focuses on optimizing the design routines of an MJ-class Superconducting Magnetic Energy Storage (SMES) unit using an intelligent optimization method known as Non-dominated Sorting Genetic Algorithm II. SMES units are among the potential storage devices for future power systems. However, due to their cooling cost, weight, and energy density, they have not yet been commercialized for power system applications. In this regard, this study discusses the impact of considering mechanical, economic, magnetoelectric, and physical objective functions during the design optimization of MJ-class SMES, as novel design functions for SMES units. The following objective functions were employed: maximization of energy density, minimization of total weight, minimization of total cooling cost, and minimization of maximum applied strain. Different loading factors were also analyzed to demonstrate their importance in the final design of SMES. This has been conducted to show how loading factor could change the final design of the SMES units. Here, loading factor is considered as the ratio of operational current to the critical current of the high temperature superconducting tapes. Results indicate that considering all the objective functions during the optimization process of SMES leads to a more realistic final design, presenting an SMES unit with a feasible structure for operation and manufacturing. Additionally, the increase in loading factor was found to reduce the heat load, increase the maximum applied strain, and raise the weight of the SMES. This underscores the significance of considering this parameter during the design process of SMES. Finally, the results of analytical model used for design of SMES have been compared with finite element results to validate the model used in this study.

Introduction: This retrospective study aimed to investigate the association between hormonal maintenance therapy and progression-free survival (PFS) in advanced (stage 3 or 4) epithelial ovarian cancer patients who achieved complete clinical remission with first-line chemotherapy. Methods: The study included 64 advanced HGSOC patients who received Tamoxifen, Letrozole or sequential Tamoxifen followed by Letrozole as maintenance therapy versus no maintenance treatment. The primary outcome measure was progression-free survival (PFS) at 12 and 24 months. The association between patients’ characteristics and PFS was also analyzed. Results: Tamoxifen and Letrozole were the most commonly used maintenance treatments. The mean PFS was 20.56 ± 11.48 months. The study found that Letrozole played a significant role in prolonging PFS compared to Tamoxifen, sequential Tamoxifen followed by Letrozole or no maintenance group. The frequency of PFS at 12 and 24 months was also reported, with Letrozole showing a better effect in the long term “P= 0.006”. The majority of patients did not have significant toxicities whilst on Letrozole or Tamoxifen. Conclusion: Hormonal therapy can be an effective maintenance treatment option for advanced ovarian cancer, and Letrozole may be a preferred option for prolonging PFS in advanced HGSOC patients.

•Predominant antifungal LAB from amaranth sourdough was used as starter culture.•Controlled fermented amaranth and purslane powder were added to wheat bread.•Application of the sourdough improved textural features and reduced mold growth.•Supplemented wheat breads with purslane powder received higher sensory scores.

Renewable energy sources, elastic loads, and purposeful manipulation of meter readings challenge the monitoring and control of today’s power systems (PS). In this context, fast and robust state estimation (SE) is timely and of major importance to maintaining a comprehensive view of the system in real-time. Conventional PSSE solvers typically entail minimizing a nonlinear and nonconvex least-squares cost using e.g., the Gauss-Newton method. Those iterative solvers however, are sensitive to initialization and may converge to local minima. To overcome these hurdles, the present paper draws recent advances on image denoising to put forth a novel PSSE formulation with a data-driven regularization term capturing a deep neural network (DNN) prior. For the resultant regularized PSSE objective, a “Gauss-Newton-type” alternating minimization solver is developed first. To accommodate real-time monitoring, a novel end-to-end DNN is constructed subsequently by unrolling the proposed alternating minimization solver. The deep PSSE architecture can further account for the power network topology through a graph neural network (GNN) based prior. To further endow the physics-based DNN with robustness against bad data, an adversarial DNN training method is put forth. Numerical tests using real load data on the IEEE 118-bus benchmark system showcase the improved estimation and robustness performance of the proposed scheme compared with several state-of-the-art alternatives.

•FTCL HTS transformer is analysed under a system level approach in a standard grid.•Two fault scenarios in two microgrids with distributed generators are considered.•Significant reduction in temperature of HTS windings due to insulation is observed.•Remarkable ability of FTCL HTS transformer under post-fault overloading.•No burnout of windings under long-duration faults, in both fault scenarios.

The application of machine learning (ML) is increasingly growing in biomedical sciences. This study aimed to evaluate factors associated with type 2 diabetes mellitus (T2DM) and compare the performance of ML methods in identifying individuals with the disease in an Iranian setting. Using the baseline data from Fasa Adult Cohort Study (FACS) and in a sex‐stratified manner, we studied factors associated with T2DM by applying seven different ML methods including Logistic Regression (LR), Support Vector Machine (SVM), Random Forest (RF), K‐Nearest Neighbours (KNN), Gradient Boosting Machine (GBM), Extreme Gradient Boosting (XGB) and Bagging classifier (BAG). We further compared the performance of these methods; for each algorithm, accuracy, precision, sensitivity, specificity, F1 score, and Area Under Curve (AUC) were calculated. 10,112 participants were recruited between 2014 and 2016, of whom 1246 had T2DM at baseline. 4566 (45%) participants were males, aged between 35 and 70 years. For males, age, sugar consumption, and history of hospitalization were the most weighted variables regarding their importance in screening for T2DM using the GBM model, respectively; these variables were sugar consumption, urine blood, and age for females. GBM outperformed other models for both males and females with AUC of 0.75 (0.69–0.82) and 0.76 (0.71–0.80), and F1 score of 0.33 (0.27–0.39) and 0.42 (0.38–0.46), respectively. GBM also showed a sensitivity of 0.24 (0.19–0.29) and a specificity of 0.98 (0.96–1.0) in males and a sensitivity of 0.38 (0.34–0.42) and specificity of 0.92 (0.89–0.95) in females. Notably, close performance characteristics were detected among other ML models. GBM model might achieve better performance in screening for T2DM in a south Iranian population. Gradient Boosting Machine model might achieve better performance in screening for T2DM in a south Iranian population.

The aim of this paper was to present design procedure of High Temperature Superconducting (HTS) cables to for Space-Based Solar Power (SBSP) application. SBSP is a promising technology that can deliver an infinite amount of clean and eco-friendly energy back to the Earth. To deliver the harvested solar energy to the power systems on Earth, efficient energy transmission is critically important. To address the challenges of conventional power cables, an ideal solution would be using HTS cables. In this research, the design procedure of a Direct Current (DC) HTS cable considering electromagnetic, thermal, and cost constraints were presented. The study considered a 2MW bipolar DC HTS cable in five operational temperatures: 20K, 30K, 50K, 65K, and 77K. The results were showed that the cost and weight of the designed HTS cables were increased by operational temperature increase. However, the cooling cost of HTS cable in higher temperatures, was less than lower temperatures. Also, the total efficiency of the HTS cable and cooling system were increased, when operational temperatures were changed from 20K to 77K, from 99.70% to 99.97%, respectively. The next steps of this study would be fault performance analysis of designed HTS cables and optimization of the HTS cables, based on the different objective functions.

In the present work, carboxymethyl cellulose-based bionanocomposite hydrogel beads with diverse concentration ratios of Fe3O4-Zeolite were produced and used for the removal of Imidacloprid from an aqueous solution. Optimization of various factors such as Imidacloprid initial concentration, adsorbent dosage, pH solution, and sonicating time (42kHz) affecting Imidacloprid removal was evaluated by response surface methodology (RSM). The optimum values for these parameters were obtained at 38mgL-1, 1.9gL-1, 7, and 19min, respectively. The adsorption process of Imidacloprid by CMC/Fe3O4-Zeolite20 is multilayer adsorption (Jossens model) and was controlled by internal and external diffusion (double-exponential model). Additionally, the study of the ultrasonic effect on Imidacloprid removal performance showed that the ultrasound combined with adsorption significantly reduces the equilibration time. Also, the adsorption and desorption study showed that the adsorbent with high stability in adsorption performance was recycled in 6 cycles without a significant reduction in adsorption efficiency. And finally, the removal performance of CMC/Fe3O4-Zeolite20 was studied on the real wastewater samples and confirmed the feasibility of adsorbent for practical applications in industrial purposes.

ABSTRACTThis paper studies high-temperature creep deformation of Mg retort tubes considering the decarburisation of steel. A material model was developed for finite element modelling that relates the activation energy of steel in the steady-state creep rate equation (Q) to its carbon content. Carbon content was described as a function of radial position along the retort thickness (r) and service time (t). The time-dependent activation energy, Q(C(r,t)), was incorporated in the steady-state creep equation. The FEM results of the decarburising model were compared to those of the non-decarburising model and an actually failed retort for verification. The newly developed model presents more accurate results compared to the constant material model (non-decarburising). The FE model was used to predict the effects of various process parameters (temperature, internal pressure, and furnace carbon activity) and geometric parameters (retort diameter and thickness) on the creep deformation of retorts.

Purpose:Few studies have summarized findings for the effect of metformin on obesity indices. Therefore, we aimed to conduct a systematic review and meta-analysis on the effect of metformin on obesity indices among children and adolescents.Methods:Relevant articles published up to September 2018 were searched in SCOPUS, Medline, and Google Scholar using appropriate keywords. All clinical trials that examined the effect of metformin on obesity indices in children and adolescents were included.Results:Overall, 38 studies, including 2199 participants (39.75% male and 60.25% female), were included. The pooled results indicated that metformin significantly reduced BMI [weighted mean difference (WMD): −1.07 kg/m2; 95% confidence interval (CI): −1.43 to −0.72]. Same findings were found for waist circumference (WC) (WMD: −1.93 cm; 95% CI: −2.69 to −1.16). Metformin also reduced body weight in all participants (WMD: −2.51 kg; 95% CI: −3.14 to −1.89). Moreover, it reduced body fat mass in patients with overweight or obesity (WMD: −1.90%; 95% CI: −3.25 to −0.56) and chronic diseases (WMD: −1.41%; 95% CI: −2.23 to −0.58), but not among those with growth problems. Metformin therapy did not affect lean body mass (LBM) in patients with overweight or obesity and growth problems; however, it reduced LBM in patients with chronic diseases (WMD: −1.49 kg; 95% CI: −2.69 to −0.30).Conclusions:We found a significant reduction in BMI, body weight, WC, and fat mass following administration with metformin. However, the effect of metformin on LBM was not significant. Further studies are required to confirm these findings.

A multi-strategic approach was used to manufacture functional bread with health and safety promoting effects. Firstly, predominant LAB strains isolated from mature spontaneous rice bran sourdough (RBS) were screened based on their radical-scavenging activities. Then the selected isolate was identified by a PCR based method. After that, the inhibitory effects of the LAB isolate on Aspergillus nigerand Penicillium verrucosumwere investigated. Subsequently, the optimized formulation of the controlled RBS (fermented with this isolate as starter culture) along with pumpkin puree was determined based on antioxidant capacity of the product using response surface methodology (RSM). The sequencing results led to the identification of the LAB isolate as Lactobacillus plantarum. In vitro antifungal activities of the LAB isolate were also approved.Furthermore, the results revealed that controlled RBS and pumpkin puree synergistically improved the techno-functional properties of the product in terms of hardness, overall acceptability as well as antioxidant capacity. Mould growth on bread containing controlled RBS was significantly (P< 0.05) lower than the control. According to these results, simultaneous application of the controlled RBS along with pumpkin puree in bread roll is important from technological, sensorial and functional viewpoints in processing of this product. Furthermore, controlled RBS along with pumpkin puree can be used as fiber rich supplements in bread making to produce a clean label food, and to develop not only a safer but also an innovative bakery product.

Incidence of drug-drug interactions (DDIs) has been widely reported; however, such reports in pediatric oncology patients still remain scarce. We studied frequency and demographic correlates of moderate and major DDIs at a pediatric oncology ward in Isfahan, Iran. All pediatric oncology patients admitted to the Omid hospital during a 6-month period (2017) who received at least 2 anticancer or non-anticancer drugs concomitantly were included in our study. Potential DDIs between anticancer and non-anticancer drugs during hospitalization was identified using Lexi-Interact on-line software. We detected 194 DDIs with moderate or major severity for our included 115 patients. Mechanistically, most of DDIs (56.4%) were pharmacodynamic. Systematic use of corticosteroids (82.0%), antimetabolites (77.0%), and antiemetic drugs (69.5%) were the most frequent medication classes responsible for detected DDIs. The interaction between aminoglycosides and the third generation cephalosporins was the most common (13.9%) non-anticancer DDI. The only identified interaction between 2 anticancer drugs was doxorubicin with cyclophosphamide. Age, sex, and the number of administered medications were associated with DDIs. Potential moderate or major DDIs occur frequently among pediatric cancer patients. More studies are needed to assess clinical and economic implications of DDIs in pediatric oncology patients.

In the present research, polyaniline is used as a conducting polymer and polyvinyl alcohol is also used as a biopolymer, because of its mechanical properties and suitable processability. Also, silver nanoparticles are considered as a reinforcing agent of thermal stability, mechanical and antibacterial properties to prepare polyaniline-polyvinyl alcohol-silver nanocomposite. The synthesis of polyaniline-polyvinyl alcohol composite and polyaniline-polyvinyl alcohol-silver nanocomposite is performed through addition of polyaniline and silver in polyvinyl alcohol solution. In order to review thermal, mechanical and antibacterial properties of synthesized composite and nanocomposites, components with different weight rates are used. The obtained results from thermogravimetric analysis (TGA) tests also indicate promotion of thermal stability of polyaniline-polyvinyl alcohol-silver nanocomposite compared with pure polyvinyl alcohol in temperatures above 400°C. The results of Fourier-transform infrared (FTIR) spectroscopy revealed the presence of polyaniline, polyvinyl alcohol and silver in the structure of polyaniline-polyvinyl alcohol-silver triple nanocomposite film. The obtained results from a review of antibacterial properties showed that polyaniline-polyvinyl alcohol-silver nanocomposites have antibacterial effects on two different types of Gram-positive and Gram-negative bacteria. The obtained results from a review of mechanical properties of nanocomposites showed that the greatest value of tensile strength (13.8 MPa) belonged to polyaniline-polyvinyl alcohol-silver (88%/9%/3% w/w) nanocomposites. Therefore, this is determined as an optimal triple nanocomposite. In addition, scanning electron microscopy (SEM) coupled with an energy dispersive X-ray (EDX) system was used to characterize the composition and structure of polyaniline-polyvinyl alcohol-silver nanocomposite film.

In this study, microstructural evolution and mechanical properties of commercial purity titanium after a combined equal channel angular pressing (ECAP) and warm caliber rolling (WCR) was investigated. The ECAP process was applied to enhance the hardness and strength of the specimen by decreasing the grain size and producing UFG microstructure. WCR was applied to reduce cross-section and increase the ductility of the ECAPed specimens. Results show that WCR reduces the work-hardening rate by increasing grain size and also increases elongation and workability while it reduces the yield and ultimate tensile strength. It has been shown that the strength ratio ($${{\sigma_{UTS} } \mathord{\left/ {\vphantom {{\sigma_{UTS} } {\sigma_{y} }}} \right. \kern-0pt} {\sigma_{y} }}$$ σUTSσy ) and strain ratio ($${{\varepsilon_{UTS} } \mathord{\left/ {\vphantom {{\varepsilon_{UTS} } {\varepsilon_{t} }}} \right. \kern-0pt} {\varepsilon_{t} }}$$ εUTSεt ) of the processed samples are comparatively larger than all previously post processed ECAPed materials at lower temperatures.

In this work, improving the abrasion–corrosion behavior of gray cast iron used in centrifugal pumps was studied. These pumps are usually made of gray cast iron (BS:1452Gr220) and are repaired by Shielded Metal Arc Welding (SMAW). Three different typical welding electrodes including Ni electrode (DIN8563), Carbon Steel electrode (DIN1913), and Hardening electrode (DIN8555) were used to compare the weldability of the base metal. Microstructural differences for three types of electrodes were studied and forming of different phases was analyzed. Corrosion and abrasion tests were conducted and related to welding conditions. Experimental results showed that using Ni substrate electrode reduce the unwanted phases (martensitic and carbides). Furthermore, in comparison with the base metal, the abrasion behavior of all weldments was improved. It was also determined that the carbon steel electrode has a higher corrosion resistance in zero-resistance ammeter (ZRA) test compared to other electrodes.

In parallel with the meteoric rise of mobile software, we are witnessing an alarming escalation in the number and sophistication of the security threats targeted at mobile platforms, particularly Android, as the dominant platform. While existing research has made significant progress towards detection and mitigation of Android security, gaps and challenges remain. This paper contributes a comprehensive taxonomy to classify and characterize the state-of-the-art research in this area. We have carefully followed the systematic literature review process, and analyzed the results of more than 300 research papers, resulting in the most comprehensive and elaborate investigation of the literature in this area of research. The systematic analysis of the research literature has revealed patterns, trends, and gaps in the existing literature, and underlined key challenges and opportunities that will shape the focus of future research efforts.

•Analytical formulations for critical current parameterization were presented.•Fuzzy logic were used to parameterize critical current.•Comparing to ANFIS and ANN, fuzzy logic has higher accuracy.•Accuracy and adaptability of fuzzy method is way better than analytical approaches.

There is a growing interest in the production of probiotics (PRO) enriched food and pharmaceutical products as personalized nutrition and/or medicines. Due to the limitations associated with PRO such as their survival and targeted delivery in food/gastrointestinal matrices, it is necessary to introduce the next-generation PRO (NGPs). Combined formulation of PRO and nanomaterials (NMs) as a promising progress in nano-biotechnology has interesting potential applications. These NMs as proper carrier or coating agents have pivotal importance in food/drug applications of NGPs. There are several case studies related to the unique and promising capabilities of NMs for targeted delivery, long-term viability and stability of PRO, as well as potent infection control by these essential microorganisms and engineering of the smart constructs with enhanced functionalities using these innovative valuable platforms. Furthermore, surface to volume ratio of the produced constructs and adhesion of the PRO onto the intestinal epithelial mucus can be improved using novel NMs. Although integration of PRO with nanostructured platforms has promising beneficial effects, there are some limitations such as potential inhibitory effect of NMs on metabolic activity of PRO that needs to be considered. Furthermore, potential interactions between NMs and food components, their potential side effects on gut hemostasis, as well as concerns about their toxicity and biosafety are important issues in this context. This review sought to present and discuss the most recent cutting-edge publications associated with capabilities of NMs to improve crucial functionalities of the NGPs for their essential and innovative applications.

In the present study, a layer-by-layer technique was used to prepare alginate-nisin (Alg-N) as coating layer to encapsulate a potential probiotic-protective lactic acid bacteria (LAB) isolate in order to improve its both survival and antibacterial activities in situ. The isolate was identified as Pediococcus acidilacticiaccording to the sequencing results of the PCR products. The mean size of Alg and Alg-N microcapsules was also equal to 762.63 and 501.77 μm, respectively based on the results of field emission scanning electron microscopy. In accordance with the zeta potential data, the Alg-N surrounding layer was confirmed. Furthermore, the Fourier transform infrared findings revealed the adsorption of nisin on the Alg beads. The antibacterial activity of the produced microcapsule on Staphylococcus aureus(100% inhibition) was significantly (P < 0.05) higher than that of the other foodborne bacteria studied. In addition, enhanced viability of the microencapsulated LAB in simulated gastrointestinal conditions and flavored milk, as well as its improved in situinhibitory effect on S. aureuswere verified.

Android is the most popular platform for mobile devices. It facilitates sharing of data and services among applications using a rich inter-app communication system. While access to resources can be controlled by the Android permission system, enforcing permissions is not sufficient to prevent security violations, as permissions may be mismanaged, intentionally or unintentionally. Android’s enforcement of the permissions is at the level of individual apps, allowing multiple malicious apps to collude and combine their permissions or to trick vulnerable apps to perform actions on their behalf that are beyond their individual privileges. In this paper, we present COVERT, a tool for compositional analysis of Android inter-app vulnerabilities. COVERT’s analysis is modular to enable incremental analysis of applications as they are installed, updated, and removed. It statically analyzes the reverse engineered source code of each individual app, and extracts relevant security specifications in a format suitable for formal verification. Given a collection of specifications extracted in this way, a formal analysis engine (e.g., model checker) is then used to verify whether it is safe for a combination of applications—holding certain permissions and potentially interacting with each other—to be installed together. Our experience with using COVERT to examine over 500 real-world apps corroborates its ability to find inter-app vulnerabilities in bundles of some of the most popular apps on the market.

Catalyst coated membranes (CCMs) in polymer electrolyte fuel cells are subjected to mechanical stresses in the form of fatigue and creep that deteriorate the durability and lifetime of the cells. The present article aims to determine the effect of in-situ hygrothermal fatigue on the microstructure and mechanical properties of the CCM. The fatigue process is systematically explored by the application of two custom-developed accelerated mechanical stress test (AMST) experiments with periodic extraction of partially degraded CCMs. Cross sectional and top surface scanning electron microscope (SEM) images of the end-of-test CCMs reveal the formation of mechanically induced cracks and delamination due to cyclic tensile and compressive fatigue stress. Tensile and expansion tests are conducted at different stages of degradation to evaluate the evolution in the mechanical and hygrothermal properties of the CCM. The tensile test results indicate gradual reductions in final strain, ultimate tensile strength, and fracture toughness with increasing number of fatigue cycles. The decay in tensile properties is attributed to the microstructural damage and micro-cracks formed during the AMST. Moreover, it is shown that the hygrothermal expansion of the CCM is more sensitive to conditioning than mechanical degradation.

Regular durability testing of heavy duty fuel cell systems for transit bus application requires several thousand hours of operation, which is costly and time consuming. Alternatively, accelerated durability tests are able to generate failure modes observed in field operation in a compressed time period, by applying enhanced levels of stress. The objective of the present work is to design and validate an accelerated membrane durability test (AMDT) for heavy duty fuel cells under bus related conditions. The proposed AMDT generates bus relevant membrane failure modes in a few hundred hours, which is more than an order of magnitude faster than for regular duty cycle testing. Elevated voltage, temperature, and oxidant levels are used to accelerate membrane chemical stress, while relative humidity (RH) cycling is used to induce mechanical stress. RH cycling is found to significantly reduce membrane life-time compared to constant RH conditions. The role of a platinum band in the membrane is investigated and membranes with Pt bands demonstrate a considerable life-time extension under AMDT conditions, with minimal membrane degradation. Overall, this research serves to establish a benchmark AMDT that can rapidly and reliably evaluate membrane stability under simulated heavy duty fuel cell conditions.

The use of perforator flaps has allowed for the transfer of large amounts of soft tissue with decreased morbidity. For breast reconstruction, the deep inferior epigastric perforator flap, the superior and inferior gluteal artery perforator flaps, and the transverse upper gracilis flap are all options. The authors present an alternative source using posterior thigh soft tissue based on profunda artery perforators, termed the profunda artery perforator flap.

The bonding strength, and microstructures of Cu and Al couples using metallic powders as interlayer during transient liquid phase bonding (TLP bonding) were investigated. The interfacial morphologies and microstructures were studied by scanning electron microscopy equipped with energy dispersive X-ray spectroscopy, and X-ray diffraction. First, to explore the optimum bonding time and temperature, nine samples were bonded without interlayers in a vacuum condition. Mechanical test results indicated that bonding at 560°C in 20 min returns the highest bond strength (84% of Al). This bonding condition was used to join ten samples with powder interlayers. Powders were prepared by mixing different combinations of Cu, Al (+Fe nanoparticles) and Zn. In the bonding zone, different Cu9Al4, CuAl, and CuAl2intermetallic co-precipitate. The strongest bonding is formed in the sample with the 70Al (+Fe)-30Cu powder interlayer. Powder interlayers present thinner and more uniform intermetallic layers at the joint interface.