Conventional Counterparts Research Articles

Enhancing Solar Thermal Efficiency: PCM Integration for Compact Energy Storage Systems

The optimal utilization of solar energy presents a challenge in meeting round-the-clock hot water demands while accommodating limited space in modern architectural designs. Solar collectors, operating solely during daylight hours and weather-dependent, necessitate efficient energy storage to meet evening and morning peak hot water consumption in households. Current architectural trends, marked by smaller boiler rooms, further compound the challenge of integrating conventional solar tanks, emphasizing the critical need for compact energy storage solutions. Addressing this challenge, this paper proposes a ground-breaking solution: a solar tank infused with phase change material (PCM). This innovative tank design not only boasts smaller dimensions but also significantly higher heat capacity compared to conventional counterparts. Crucially, the PCM solar tank enables solar collectors to operate at lower temperatures, potentially elevating the overall efficiency of the solar collector system. The proposed storage system comprises two synergistic heat-absorbing units: a solar water heater and a PCM-based heat storage unit. While the solar water heater fulfills the daytime hot water supply, the PCM storage unit accumulates and retains heat throughout the day, ensuring continuous hot water availability during night hours and overcast periods. Leveraging small cylinders filled with paraffin, serving as the PCM, integrated with solar collectors maximizes solar energy absorption and storage. This paper meticulously compares the performance of the PCM-based thermal energy storage system with conventional sensible heat storage systems, presenting insightful conclusions derived from the comparative analysis. The findings underscore the remarkable efficiency and efficacy of the PCM-based solution in meeting the challenges posed by solar energy intermittency and limited space constraints, offering a promising avenue for sustainable and efficient solar energy utilization in residential settings.

Sensory attributes and quality perception of red natural wines: a comparative study in Spain and France

Although the definition of natural wine remains contested and still lacks official recognition, it can be broadly described as a wine made with organic or biodynamic grapes without oenological additives in the cellar and minimal intervention in all winemaking stages. Despite growing interest in natural wines, uncertainty prevails about their sensory and quality attributes among both consumers and experts. In light of this research gap, this study aims to determine, first, if there are specific sensory dimensions allowing to differentiate natural wine as a wine category from conventional wines; second, if this sensory dimension affects the perception of the quality; and third, to characterise the physicochemical differences in terms of basic oenological parameters between natural wines and their conventional counterparts. To do so, 24 red wines (12 self-defined as natural and 12 conventional wines) were sensory and chemically characterised. The sensory evaluation was first carried out by winemakers from Spain. It consisted of a descriptive task (labelled sorting task) followed by a quality evaluation under two conditions: with and without information regarding the production method. A second panel of French experts carried out the same quality assessment, also with and without information. The aim was to find out whether expectations existed linked to each type of wine and to explore potential cross-cultural effects. The results of the labelled sorting task showed that natural wines tended to be different from conventional wines, but the difference was not clear-cut. However, natural wines were perceived to be of lower quality than their conventional counterparts, both with and without the information provided, regardless of the origin of winemakers. Results of the chemical analysis showed that natural wines presented higher values for volatile and total acidity and turbidity, while they had lower values for total and free sulphur. The study points to the existence of sensory dimensions with an impact on overall quality associated with the production method.

Comparative Meta-Analysis of Minimally Invasive and Conventional Approaches for Caries Removal in Permanent Dentition.

Background and Objectives: Addressing deep carious lesions poses significant challenges in daily dental practice due to the inherent complexity of their treatment. Traditionally, complete removal of carious tissues has been the norm, potentially leading to pulp tissue exposure and subsequent pulpitis. In contemporary dentistry, there is a growing preference for minimally invasive techniques, such as selective removal, offering a more conservative approach with enhanced predictability and success rates. Materials and Methods: Our study commenced with a comprehensive systematic review. After that, we performed a meta-analysis focused exclusively on randomized controlled trials involving permanent dentition. Our investigation incorporated seven selected articles, which scrutinized success rates and the incidence of pulp exposure in minimally invasive techniques (MIT) versus conventional techniques (CT). Statistical analysis employed U Mann-Whitney and Wilcoxon tests to interpret the results. Results: Although the difference did not reach statistical significance, MIT demonstrated marginally superior success rates compared to CT. Furthermore, MIT exhibited a lower percentage of pulp exposure when contrasted with CT. However, due to the limited sample size, statistical significance for this difference could not be established. Conclusions: Minimally invasive techniques for caries removal emerge as a conservative and promising approach to safeguard pulp tissues in comparison to conventional techniques. The need for additional randomized controlled trials is emphasized to unequivocally establish the superior success rates of these procedures over their conventional counterparts.

Solvothermal single‐pot synthesis of Pd‐Fe3O4@GO catalyst: Enhanced catalytic performance in Sonogashira coupling reactions

In this study, we present a new approach to synthesizing a magnetically separable Pd‐Fe3O4@GO catalyst using a simple single‐pot method. The catalyst was employed in Sonogashira coupling reactions, demonstrating excellent results. The catalyst was studied using a various characterization method, including X‐ray photoelectron spectroscopy (XPS), scanning electron microscope–energy‐dispersive X‐ray spectroscopy (SEM‐EDS) mapping, TEM, X‐ray diffraction (XRD), FTIR, and inductively coupled plasma mass spectrometry (ICP‐MS). Pd‐Fe3O4@GO exhibited superior catalytic activity compared with its conventional counterparts in phenylacetylene‐iodobenzene coupling reactions under copper co‐catalyzed‐free and ligand‐free conditions, with a higher turnover frequency (TOF) of 118.3 h−1. Optimized conditions yielded high yields for various substrates, including inactive aryl chloride and bromide substrates, emphasizing its versatility. Also, a reaction mechanism was proposed and a kinetic model was developed. The catalyst's green chemistry potential was highlighted because of its high efficiency, purity of products, recoverability, and ease of preparation. Moreover, Pd‐Fe3O4@GO demonstrated impressive stability through multiple recycling rounds without loss of functionality, making it a promising tool for sustainable chemical processes.

RoBUTCHER: A novel robotic meat factory cell platform

Automation is critically important for sustainability in meat production, where heavy reliance on human labour is a growing challenge. In this work, a novel robotic Meat Factory Cell (MFC) platform presents the opportunity for unconventional automation in pork meat processing, particularly abattoirs. Instead of following line-based approaches, which are the main option today, it uses robotics and Artificial Intelligence (AI) to perform complex cutting and manipulation operations on entire unchilled pork carcasses, with awareness of biological variation and deformation. The long-term goal of the MFC is to take a pork carcass as an input and produce seven primal outputs: hams, shoulders, saddle, belly and entire organ set. However, the MFC platform is under continuous development – therefore, this paper aims to demonstrate it through a specific use-case: shoulder removal. The system is evaluated based on data from testing and development sessions (June–November 2022), with a total of 34 attempted shoulder removals. Data regarding the MFCs’ ability to handle variation, in addition to success rate and process timing models are presented. Qualitative feedback from skilled butchers is also discussed. The authors propose that, as well as technical development of the platform, it is important to consider new ways of comparing unconventional systems with their conventional counterparts. Innovative manufacturing systems have more to offer than raw speed and volume; traits such as flexibility, robustness and scalability – particularly economic scalability – should play a prominent role. Future legislation and standards must also encourage innovation rather than hinder innovative robotics solutions.

Supported Ionic Liquid Membrane with Highly-permeable Polyamide Armor by In Situ Interfacial Polymerization for Durable CO2 Separation.

Supported ionic liquid membranes (SILMs), owing to their capacities in harnessing physicochemical properties of ionic liquid for exceptional CO2 solubility, have emerged as a promising platform for CO2 extraction. Despite great achievements, existing SILMs suffer from poor structural and performance stability under high-pressure or long-term operations, significantly limiting their applications. Herein, a one-step and in situ interfacial polymerization strategy is proposed to elaborate a thin, mechanically-robust, and highly-permeable polyamide armor on the SILMs to effectively protect ionic liquid within porous supports, allowing for intensifying the overall stability of SILMs without compromising CO2 separation performance. The armored SILMs have a profound increase of breakthrough pressure by 105% compared to conventional counterparts without armor, and display high and stable operating pressure exceeding that of most SILMs previously reported. It is further demonstrated that the armored SILMs exhibit ultrahigh ideal CO2/N2 selectivity of about 200 and excellent CO2 permeation of 78 barrers upon over 150h operation, as opposed to the full failure of CO2 separation performance within 36h using conventional SILMs. The design concept of armor provides a flexible and additional dimension in developing high-performance and durable SILMs, pushing the practical application of ionic liquids in separation processes.

Thermoelectric cooler with embedded teardrop-shaped milli-channel heat sink for electronics cooling

Thermoelectric coolers (TECs) offer a site-specific, on-demand, and solid-state thermal management solution for on-chip electronics cooling. To maximize their cooling performance, it is essential to integrate an effective heat exchanger, such as microchannels, on the TEC’s hot side. However, traditional microchannel heat sinks pose challenges, including the necessity for high-cost equipment and the manifestation of deleterious parasitic contact thermal resistance with the TEC. Recent studies have demonstrated the superior performance of teardrop-shaped microchannels compared to their conventional counterparts, yet their effectiveness at the milli-scale remains unexplored. In this work, through systematic numerical simulations across nine milli-channels with distinct variable cross-sections, we propose a teardrop-shaped milli-channel heat sink designed for fabrication through cost-effective mechanical machining. The optimized teardrop-shaped milli-channel exhibits a superior overall thermo-hydraulic performance evaluation factor (PEC) of approximately 1.8 with respect to its rectangular cross-sectional counterpart. Furthermore, we seamlessly embed the designed milli-channel heat sink into the substrate of the TEC to mitigate the parasitic contact thermal resistance. Measurements on the TEC embedded with the teardrop-shaped milli-channel heat sink show that the cold end temperature reaches a minimum value of −18.6 °C at an optimal input electrical current of 3.5 A and an inlet coolant flow velocity of 0.2 m/s. This temperature represents an improvement of approximately 3.5 °C and 4.4 °C compared to the TEC with an attached teardrop-shaped milli-channel and a conventional water block heat sink, respectively, under identical operating conditions. Additionally, a prototype TEC cooling system with the embedded teardrop-shaped milli-channel for high-power field-effect transistor (FET) cooling is demonstrated. Operating at an input electrical current of 3.5 A and an inlet flow velocity of 0.6 m/s, our proposed TEC cooling system achieves a steady-state working temperature of 51.3 °C for the FET at a high heat flux of 75 kW/m2, outperforming the TEC with an attached teardrop-shaped milli-channel and a conventional water block heat sink by approximately 1.4 °C and 2 °C, respectively.

Zinc oxide and ferric oxide nanoparticles combination increase plant growth, yield, and quality of soybean under semiarid region

Zinc (Zn) and iron (Fe) malnutrition are global health challenges that need immediate attention. Hence, to address these issues, a two-pronged approach involving the development and application of novel Zn and Fe products for crop fertilization may be a potential solution. Therefore, zinc oxide (ZnO) (∼13.2 nm) and ferric oxide (Fe2O3) (∼15 nm) nanoparticles (NPs) were synthesized and characterized. Seven nutrients treatments viz, control, ZnO- NPs (25 mg kg−1), Fe2O3-NPs (25 mg kg−1), ZnO + Fe2O3-NPs (25 mg kg−1each), ZnSO4 (55.8 mg kg−1), FeSO4 (60.4 mg kg−1) and ZnSO4+ FeSO4 (55.8 and 60.4 mg kg−1) were arranged in five-time replicated Completely Randomized Design model to test the effectiveness of ZnO and Fe2O3 NPs in two soybean cultivars over conventional zinc sulfate (ZnSO4) and ferrous sulfate (FeSO4) fertilizers. The results indicated that the photosynthetic rate (Pn) and chlorophyll content increased (33.9–86.2%) significantly at the flowering stage with ZnO and Fe2O3 NPs applications, compared to their conventional counterparts. Likewise, the combined application of ZnO and Fe2O3 NPs reduced H2O2 production by 17–19% and increased the superoxide dismutase (SOD) and catalase (CAT) activities by 15–17% and 9.6–11.4% over the combined use of ZnSO4 and FeSO4, respectively. The normalized difference vegetation index (NDVI) showed an increase of 6.9–44.2% under ZnO and Fe2O3 NPs, as well as ZnSO4 and FeSO4. Furthermore, the combined application of NPs enhanced soybean seed yield by 4.6–18.3% compared to conventional Zn and Fe fertilizers. Concerning seed Zn and Fe density, conjoint application of ZnO and Fe2O3 NPs increases Zn by 1.8–2.2-fold and Fe by 19.22–22.58% over the combined application of Zn SO4 and FeSO4, respectively. While the application of NPs significantly decreased seed phytic acid concentrations by 7.3–59.9% compared to the control. These findings suggest that the combined application of ZnO and Fe2O3 NPs effectively enhances soybean productivity, seed nutrient density, and overall produce quality. Therefore, the combined application of ZnO and Fe2O3 -NPs in soybean can be a potential approach for sustainable soybean production and to reduce/arrest Zn and Fe malnutrition in a growing population.

Monolithic fully-controlled HEMT bidirectional power switch with merged Schottky barrier diodes and p-GaN gate transistors for ultra-low turn-on voltage and high threshold voltage

A monolithic fully-controlled high electron mobility transistor (HEMT) bidirectional power switch (FC-HEMT BPS) is studied and implemented for ultra-low turn-on voltage and high threshold voltage. The alternately embedded recess Schottky barrier diodes with p-GaN gate HEMTs in the common active region is a distinctive feature of the proposed device. The FC-HEMT BPS is a sophisticated device with two independent gate controls, capable of operating in four distinct modes. Its flexibility in managing current and voltage in the first and third quadrants makes it versatile for a range of applications in power electronics. The proposed device offers notable advantages over conventional counterparts, including reduced turn-on voltage V ON-D of ∼0.4 V in diode modes and the elimination of turn-on voltage V ON-B (i.e. 0 V) in bidirectional conduction mode. These features make it a promising solution for efficient power electronics applications.

Antibacterial biofilm efficacy of calcium hydroxide loaded on Gum Arabic nanocarrier: an in-vitro study

BackgroundAn innovative intracanal medication formulation was introduced in the current study to improve the calcium hydroxide (Ca(OH)2) therapeutic capability against resistant Enterococcus faecalis (E. faecalis) biofilm. This in-vitro study aimed to prepare, characterize, and evaluate the antibacterial efficiency of Ca(OH)2 loaded on Gum Arabic (GA) nanocarrier (Ca(OH)2-GA NPs) and to compare this efficiency with conventional Ca(OH)2, Ca(OH)2 nanoparticles (NPs), GA, and GA NPs.Materials and methodsThe prepared nanoparticle formulations for the tested medications were characterized using Transmission Electron Microscope (TEM) and Fourier-Transform Infrared Spectroscopy (FTIR). 141 human mandibular premolars were selected, and their root canals were prepared. Twenty-one roots were then sectioned into 42 tooth slices. All prepared root canals (n = 120) and teeth slices (n = 42) were divided into six groups according to the intracanal medication used. E. faecalis was inoculated in the samples for 21 days to form biofilms, and then the corresponding medications were applied for 7 days. After medication application, the residual E. faecalis bacteria were assessed using CFU, Q-PCR, and SEM. Additionally, the effect of Ca(OH)2-GA NPs on E. faecalis biofilm genes (agg, ace, and efaA) was investigated using RT-PCR. Data were statistically analyzed at a 0.05 level of significance.ResultsThe synthesis of NPs was confirmed using TEM. The results of the FTIR proved that the Ca(OH)2 was successfully encapsulated in the GA NPs. Ca(OH)2-GA NPs caused a significant reduction in the E. faecalis biofilm gene expression when compared to the control (p < 0.001). There were significant differences in the E. faecalis CFU mean count and CT mean values between the tested groups (p < 0.001) except between the Ca(OH)2 and GA CFU mean count. Ca(OH)2-GA NPs showed the least statistical E. faecalis mean count among other groups. SEM observation showed that E. faecalis biofilm was diminished in all treatment groups, especially in the Ca(OH)2-GA NPS group when compared to the control group.ConclusionsCa(OH)2 and GA nanoparticles demonstrate superior anti-E. faecalis activity when compared to their conventional counterparts. Ca(OH)2-GA NPs showed the best antibacterial efficacy in treating E. faecalis biofilm. The tested NP formulations could be considered as promising intracanal medications.

Towards Designing Durable Sculptural Elements: Ensemble Learning in Predicting Compressive Strength of Fiber-Reinforced Nano-Silica Modified Concrete

Fiber-reinforced nano-silica concrete (FrRNSC) was applied to a concrete sculpture to address the issue of brittle fracture, and the primary objective of this study was to explore the potential of hybridizing the Grey Wolf Optimizer (GWO) with four robust and intelligent ensemble learning techniques, namely XGBoost, LightGBM, AdaBoost, and CatBoost, to anticipate the compressive strength of fiber-reinforced nano-silica concrete (FrRNSC) for sculptural elements. The optimization of hyperparameters for these techniques was performed using the GWO metaheuristic algorithm, enhancing accuracy through the creation of four hybrid ensemble learning models: GWO-XGBoost, GWO-LightGBM, GWO-AdaBoost, and GWO-CatBoost. A comparative analysis was conducted between the results obtained from these hybrid models and their conventional counterparts. The evaluation of these models is based on five key indices: R2, RMSE, VAF, MAE, and bias, addressing an objective assessment of the predictive models’ performance and capabilities. The outcomes reveal that GWO-XGBoost, exhibiting R2 values of (0.971 and 0.978) for the train and test stages, respectively, emerges as the best predictive model for estimating the compressive strength of fiber-reinforced nano-silica concrete (FrRNSC) compared to other models. Consequently, the proposed GWO-XGBoost algorithm proves to be an efficient tool for anticipating CSFrRNSC.

Revolutionizing Digital Signal Filters: A Breakthrough in Low-Power Multipliers

In the ever-evolving landscape of digital signal processing technology, the ubiquitous presence of digital signal filters has become a cornerstone across a myriad of domains including radar, computing, and communications. Amidst the relentless pursuit of more efficient solutions, a pivotal development emerges - the creation of a low-power multiplier tailored explicitly for digital signal filters. This innovation hinges upon the judicious selection of a carry-lookahead adder as a fundamental building block within the multiplier, ushering in enhancements that ripple through its operation. This transformative leap doesn't halt at the component level; it extends its reach further by delving into meticulous optimizations encompassing logic gate dimensions and set voltage parameters. These refinements, executed with precision, culminate in a substantial reduction in the energy consumption of the multiplier, effectively setting it apart from conventional counterparts. Remarkably, these advances don't merely remain theoretical; they find their footing in practical industry applications, thus birthing a new era in the creation of low-power digital signal filters. The profound implications of this development reverberate far and wide, notably benefiting the realm of low-power digital signal processing and its associated applications.

SslTransT: Self-supervised pre-training visual object tracking with Transformers

Transformer-based visual object tracking surpasses conventional CNN-based counterparts in superior performance but comes with additional computational overhead. Existing Transformer-based trackers rely on large-scale annotated data and longer training periods. To address this issue, we introduce a self-supervised pretext task, named target localization, which randomly crops the target and then pastes it onto various background images. The copy-paste-transform data augmentation strategy can composite sufficient training data and facilitate routine training. In addition, freezing the CNN backbone during pre-training and randomly adjusting template and search area factors further lead to faster training convergence. Extensive experiments both on public tracking benchmarks and real aircraft flight test videos demonstrate that our proposed tracker SslTransT significantly outperforms the baseline performance while requiring only half the training time. Furthermore, we apply SslTransT to a 6D pose measurement system based on vision and laser ranging, achieving excellent tracking results while running in real-time.

Bloch Point Quadrupole Constituting Hybrid Topological Strings Revealed with Electron Holographic Vector Field Tomography.

Topological magnetic (anti)skyrmions are robust string-like objects heralded as potential components in next-generation topological spintronics devices due to their low-energy manipulability via stimuli such as magnetic fields, heat, and electric/thermal current. While these 2D topological objects are widely studied, intrinsically 3D electron-spin real-space topology remains less explored despite its prevalence in bulky magnets. 2D-imaging studies reveal peculiar vortex-like contrast in the core regions of spin textures present in antiskyrmion-hosting thin plate magnets with S4 crystal symmetry, suggesting a more complex 3D real-space structure than the 2D model suggests. Here, holographic vector field electron tomography captures the 3D structure of antiskyrmions in a single-crystal, precision-doped (Fe0.63Ni0.3Pd0.07)3P (FNPP) lamellae at room temperature and zero field. These measurements reveal hybrid string-like solitons composed of skyrmions with topological number W = -1 on the lamellae's surfaces and an antiskyrmion (W = + 1) connecting them. High-resolution images uncover a Bloch point quadrupole (four magnetic (anti)monopoles that are undetectable in 2D imaging) which enables the observed lengthwise topological transitions. Numerical calculations corroborate the stability of hybrid strings over their conventional (anti)skyrmion counterparts. Hybrid strings result in topological tuning, a tunable topological Hall effect, and the suppression of skyrmion Hall motion, disrupting existing paradigms within spintronics.

Late-rising CD4 T cells resolve mouse cytomegalovirus persistent replication in the salivary gland.

Conventional antiviral memory CD4 T cells typically arise during the first two weeks of acute infection. Unlike most viruses, cytomegalovirus (CMV) exhibits an extended persistent replication phase followed by lifelong latency accompanied with some gene expression. We show that during mouse CMV (MCMV) infection, CD4 T cells recognizing an epitope derived from the viral M09 protein only develop after conventional memory T cells have already peaked and contracted. Ablating these CD4 T cells by mutating the M09 genomic epitope in the MCMV Smith strain, or inducing them by introducing the epitope into the K181 strain, resulted in delayed or enhanced control of viral persistence, respectively. These cells were shown to be unique compared to their conventional memory counterparts; producing higher IFNγ and IL-2 and lower IL-10 levels. RNAseq analyses revealed them to express distinct subsets of effector genes as compared to classical CD4 T cells. Additionally, when M09 cells were induced by epitope vaccination they significantly enhanced protection when compared to conventional CD4 T cells alone. These data show that late-rising CD4 T cells are a unique memory subset with excellent protective capacities that display a development program strongly differing from the majority of memory T cells.

Genetically engineered IgG1 and nanobody oligomers acquire strong intrinsic CD40 agonism

ABSTRACT Most anti-CD40 antibodies show robust agonism only upon binding to FcγR+ cells, such as B cells, macrophages, or DCs, but a few anti-CD40 antibodies display also strong intrinsic agonism dependent on the recognized epitope and/or isotype. It is worth mentioning, however, that also the anti-CD40 antibodies with intrinsic agonism can show a further increase in agonistic activity when bound by FcγR-expressing cells. Thus, conventional antibodies appear not to be sufficient to trigger the maximum possible CD40 activation independent from FcγR-binding. We proved here the hypothesis that oligomeric and oligovalent anti-CD40 antibody variants generated by genetic engineering display high intrinsic, thus FcγR-independent, agonistic activity. We generated tetra-, hexa- and dodecavalent variants of six anti-CD40 antibodies and a CD40-specific nanobody. All these oligovalent variants, even when derived of bivalent antagonistic anti-CD40 antibodies, showed strongly enhanced CD40 agonism compared to their conventional counterparts. In most cases, the CD40 agonism reached the maximum response induced by FcγR-bound anti-CD40 antibodies or membrane CD40L, the natural engager of CD40. In sum, our data show that increasing the valency of anti-CD40 antibody constructs by genetic engineering regularly results in molecules with high intrinsic agonism and level out the specific limitations of the parental antibodies.

Risk and performance of Islamic and conventional banks under COVID-19 pandemic: Evidence from MENA region

PurposeThe aim of this study is to conduct a comparative analysis between Islamic and conventional banks in terms of whether Islamic banks was more or less resilient/risky than conventional counterparts to the pandemic shock. It also examines the role of capital in improving the performance and stability within the two banking systems.Design/methodology/approachThis study uses 82 banks from MENA (Middle East and North Africa) region for periods across 2011–2020, and employs a dynamic panel data approach to examine the resilience within both banking systems during the Covid-19 pandemic.FindingsThe results show that the Covid-19 pandemic has a negative impact on conventional banks' stability. However, Islamic banks performed better and were less risky than conventional ones. Banks with high-quality capital are more effective at controlling their risks and improving their performance during the pandemic.Practical implicationsThe results offer important financial observations and policy implications to many stakeholders engaging with banks. Actually, the findings of this study facilitate to the stakeholders and bankers to have an alluded picture about determinants of risk and performance. The results can be used by bankers’ policy decision-makers to improve and enhance their consideration for risk management, taking into consideration the type of banking systems.Originality/valueCompared to the various studies on the stability of Islamic and conventional banks, researchers have not sufficiently addressed the effect of the Covid-19 pandemic on risk and performance. Moreover, none of these studies has examined if Islamic banks was more or less resilient/risky than conventional counterparts to the pandemic shock. This leads the authors to identify the similarities and differences between two types of banks in the MENA region in a pandemic shock context.

Construction of the mosaic aluminophosphate zeotypes based on nonclassical crystallization and in situ selective etching strategies

Owing to short diffusion lengths and more accessible active sites, hierarchical zeolitic materials can substantially improve catalytic activities and lifetimes compared to the conventional counterparts. Here we develop a straightforward and mesopore-template-free strategy to prepare aluminophosphate-based LTA zeotypes with mosaic architectures and hierarchical porosities. The influence of synthesis parameters and time-dependent study on the crystallization process were studied comprehensively using multiple techniques. The results demonstrate that the mosaic architectures were formed based on nonclassical crystallization, i.e., phase transformation of a lamellar phase to aligned crystalline AlPO4-42 nanoparticles followed by crystal fusion, and in situ selective etching of grain boundaries and defects. Meanwhile, heteroatom-substituted AlPO4-42 zeotypes with the mosaic morphologies can also be synthesized, which show enhanced ideal adsorbed solution theory (IAST) selectivities and efficient dynamic separation performances in the CO2/N2 mixture. This work not only provides a novel mesoporogen-free strategy for the preparation of hierarchical zeotypes, but also sheds new insight into the crystallization pathway.

Design optimization of 3D-manufactured monolithic stage for biomedical polishing applications by neural artificial network and teaching learning studying based optimization algorithm

Ultra-precision polishing engineering is a current trend in ensuring the good surface quality for biomedical applications. In precision engineering, compliant mechanism, so-called monolithic mechanism, has an increasing trend in alternating conventional rigid counterparts which can be utilized for biomedical polishing application. Therefore, this article proposes an optimal design for the monolithic stage. The stage is employed in driving the polishing head. The stage is operated within from several millimeters to hundreds of millimeters. In this article, the stage was tended to guide the head to polish the biomedical samples. Hypercube sampling design is combined with finite element method to collect the data. The teaching learning-based optimization algorithm is firstly coupled with the artificial intelligence in modeling the behaviors of the stage (resonant frequency, displacement, strain energy, and stress). Next, the teaching learning studying based optimization algorithm is extended to search the optimal parameters of the stage. Three single objective optimization scenarios and two multiobjective optimization scenarios of the monolithic stage are conducted to show the effectiveness of the offered method. The predictors were well-formed by using the teaching learning-based optimization-coupled artificial neural network. The results found that the performance indicators (R and R2) are almost equal to one with the mean square error (MSE) and root MSE values are very small. The optimal results that the stage can work with a highest frequency of 760.7903 Hz, a largest stroke of 0.7325 mm (about 732.5 μm), and a strain energy of 2.5999 mJ. Meanwhile, the von Mises stress is almost much lower than the yield strength of AL 7075-T73. The designed method can effectively use in designing the stage. The stage can be fabricated by using selective laser melting additive manufacturing technology, and it can be employed to guide the polishing head for biomedical samples.

Gradient-descent noise whitening techniques for short-reach IM-DD optical interconnects with severe bandwidth limitation.

Bandwidth limitation in optoelectrical components and the chromatic dispersion-induced power fading phenomenon cause severe inter-symbol interference (ISI) in high-speed intensity modulation and direct detection (IM-DD) optical interconnects. While the equalizer implemented in the receiver's digital signal processing procedure can mitigate ISI, it also inevitably enhances the noise located in the decayed frequency region, known as equalization-enhanced colored noise (EECN). Additionally, the nonlinear impairments of the modulator and photodetector also deteriorate the performance of the IM-DD system, especially for high-order modulation formats. In this work, we propose a gradient-descent noise whitening (GD-NW) algorithm to address EECN and extend it by introducing nonlinear kernels to simultaneously mitigate EECN and nonlinear impairments. The proposed algorithms are compared with conventional counterparts in terms of the achievable baud rate and the receiver optical power sensitivity. As a proof-of-concept experiment, we validate the principles of the proposed algorithms by successfully transmitting 360-GBd on-off-keying (OOK) and 180-GBd 4-level pulse-amplitude-modulation (PAM-4) signals in the back-to-back case under a 62-GHz brick-wall bandwidth limitation. 280-GBd OOK and 150-GBd PAM-4 transmissions are also demonstrated over 1-km standard single-mode fiber with a bit error rate below 7% hard-decision forward error correction aided by the proposed approach.