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We present a hybrid device platform for creating an electrically reconfigurable metasurface formed by the integration of plasmonic nanostructures with phase-change material germanium antimony telluride (GST). By changing the phase of GST from amorphous to crystalline through Joule heating, a large range of responses from the metasurface can be achieved. Furthermore, by using the intermediate phases of GST, the metasurface can interact with the incident light in both over-coupling and under-coupling regimes, leading to an inherently broadband response. Through a detailed investigation of the nature of the fundamental modes, we demonstrate that changing the crystalline phase of the GST at the pixel-level enables an effective control over the key properties (i.e., amplitude, phase, and polarization) of incident light. This leads to the realization of a broadband electrically tunable multifunctional metadevice enabling beam switching, focusing, steering, and polarization conversion. Such a hybrid structure offers a high-speed, broadband, and nonvolatile reconfigurable paradigm for electrically programmable optical devices such as switches, holograms, and polarimeters.

Nonlinear metasurfaces with high conversion efficiencies have been vastly investigated. However, strong dynamic tunability of such devices is limited in conventional passive plasmonic and dielectric material platforms. Germanium antimony telluride (GST) is a promising phase-change chalcogenide for the reconfiguration of metamaterials due to strong nonvolatile changes of the real and imaginary parts of the refraction index through amorphous-crystalline phase change. The orderly structured GST has an even higher potential in tunable second-harmonic generation (SHG) with a non-centrosymmetric crystal structure at the crystalline phase, while the amorphous phase of GST does not exhibit bulk second-order nonlinearity. Here, we experimentally demonstrate SHG switches by actively controlling the crystalline phase of GST for a GST-based hybrid metasurface featuring a gap-surface plasmon resonance, and a quarter-wave asymmetric Fabry–Perot (F–P) cavity incorporating GST. We obtain SHG switches with modulation depths as high as ∼ 20 dB for the wavelengths at the on-state resonance. We also demonstrate the feasibility of multi-level SHG modulation by leveraging three controlled GST phases, i.e., amorphous, semi-crystalline, and crystalline, for the gap-surface plasmon hybrid device, which features stronger light–matter interaction and has higher resonant SHG efficiencies than the asymmetric F–P cavity device at respective GST phases. This research reveals that GST-based dynamic SHG switches can be potentially employed in practical applications, such as microscopy, optical communication, and photonic computing in the nonlinear regime.

Rapidly growing demands for high-performance computing, powerful data processing, and big data necessitate the advent of novel optical devices to perform demanding computing processes effectively. Due to its unprecedented growth in the past two decades, the field of meta-optics offers a viable solution for spatially, spectrally, and/or even temporally sculpting amplitude, phase, polarization, and/or dispersion of optical wavefronts. In this review, we discuss state-of-the-art developments, as well as emerging trends, in computational metastructures as disruptive platforms for spatial optical analog computation. Two fundamental approaches based on general concepts of spatial Fourier transformation and Green’s function (GF) are discussed in detail. Moreover, numerical investigations and experimental demonstrations of computational optical surfaces and metastructures for solving a diverse set of mathematical problems (e.g., integrodifferentiation and convolution equations) necessary for on-demand information processing (e.g., edge detection) are reviewed. Finally, we explore the current challenges and the potential resolutions in computational meta-optics followed by our perspective on future research directions and possible developments in this promising area.

Nanophotonics has garnered intensive attention due to its unique capabilities in molding the flow of light in the subwavelength regime. Metasurfaces (MSs) and photonic integrated circuits (PICs) enable the realization of mass-producible, cost-effective, and efficient flat optical components for imaging, sensing, and communications. In order to enable nanophotonics with multipurpose functionalities, chalcogenide phase-change materials (PCMs) have been introduced as a promising platform for tunable and reconfigurable nanophotonic frameworks. Integration of non-volatile chalcogenide PCMs with unique properties such as drastic optical contrasts, fast switching speeds, and long-term stability grants substantial reconfiguration to the more conventional static nanophotonic platforms. In this review, we discuss state-of-the-art developments as well as emerging trends in tunable MSs and PICs using chalcogenide PCMs. We outline the unique material properties, structural transformation, and thermo-optic effects of well-established classes of chalcogenide PCMs. The emerging deep learning-based approaches for the optimization of reconfigurable MSs and the analysis of light-matter interactions are also discussed. The review is concluded by discussing existing challenges in the realization of adjustable nanophotonics and a perspective on the possible developments in this promising area.

The phase matching between the propagating fundamental and nonlinearly generated waves plays an important role in the efficiency of the nonlinear frequency conversion in macroscopic crystals. However, in nanoscale samples, such as nanoplasmonic structures, the phase-matching condition is often ignored due to the sub-wavelength nature of the materials. Here, we first show that the phase matching of the lattice plasmon modes at the fundamental and second-harmonic frequencies in a plasmonic nanoantenna array can effectively enhance the surface-enhanced second-harmonic generation. Additionally, a significant enhancement of the second-harmonic generation is demonstrated using stationary band-edge lattice plasmon modes with zero phase.

Abstract When studying the working memory (WM), the ‘slot model’ and the ‘resource model’ are two main theories used to describe how information retention occurs. The slot model shows that WM capacity consists of a certain number of predefined slots available for information storage. This theory explains that there is a binary condition during information recall in which information is either wholly maintained within a slot or forgotten. The resource model has a resolution-based approach, suggesting a continuous resource able to be distributed among a number of items in WM capacity. Recently hybrid models have been introduced, suggesting that WM may not strictly conform to only one model. Accordingly, to understand the relationship between two of the most widely used paradigms in WM evaluation, we implemented a correlational assessment in two different psychophysics tasks, an analog recall paradigm with sequential bar presentation and a delayed match-to-sample (DMS) task with checkerboard stimuli. Our study revealed significant correlations between WM performance in the DMS task and recall error, precision, and sources of errors in the sequential paradigm. Overall, the findings emphasize the importance of considering both tasks in understanding WM processes, as they shed light on the debate between the slot and resource models by revealing overlapping elements in both theories and the tasks used to evaluate WM capacity.

Abstract Background Kinase-impaired class III BRAF mutations have recently received attention as a possible prognostic factor and therapeutic target. Class III BRAF variants differ from class I and class II mutations in terms of mechanism of pathway activation and therapeutic vulnerabilities. Genomic landscape analyses of tumors in large real-world cohorts represent a great opportunity to further characterize tumor-related molecular events and treatment vulnerabilities, however, such data is not yet available for tumors with BRAF class III mutations. Methods We investigated the pan-cancer genomic landscape of BRAF class III mutations in 376,302 patients. Patients had comprehensive genomic profiling either by FoundationOne® or FoundationOne®CDx from formalin-fixed, paraffin embedded tissue biopsies. 2 patient cases that harbored BRAF class III mutations who demonstrated dramatic response to anti-EGFR treatment were presented. Results BRAF class III mutations are likely to co-occur with RAF1, NRAS and HRAS alterations, while concomitant KRAS alterations were rare. Moreover, we found that alterations that predict resistance to anti-EGFR agents were significantly less common in tumors harboring BRAF class III mutations, which is of great importance as anti-EGFR therapies are a potential targeted treatment option in these tumors. Discussion Our findings suggest a heterogenous interplay of oncogenic alterations in BRAF class III mutated tumors and have important implications for the molecular mechanisms of carcinogenesis while revealing potential therapeutic vulnerabilities. Highlights Tumors harboring BRAF class III (BRAF vIII) mutations comprise a novel subset with distinct genomic heterogeneity. BRAF vIII mutations may sensitize tumors to anti-EGFR treatments. BRAF vIII alterations show significantly less co-occurrence with alterations that predict resistance to anti-EGFR agents. Rare tumors with limited therapy options should be screened for BRAF vIII mutations as they may benefit from anti-EGFR agents.

Abstract We demonstrate two general classes of magnetophoretic transistors, called the “trap” and the “repel-and-collect” transistors, capable of switching single magnetically labeled cells and magnetic particles between different paths in a microfluidic chamber. Compared with prior work on magnetophoretic transistors operating in a two-dimensional in-plane rotating field, the use of a tri-axial magnetic field has the fundamental advantages of preventing particle cluster formation and better syncing of single particles with the general operating clock. We use finite element methods to investigate the energy distribution on the chip surface and to predict the particle behavior at various device geometries. We then fabricate the proposed transistors and compare the experimental results with the simulation predictions. We found that with gate electrical currents of ~ 40 mA for a transistor with proper geometry, complete switching of magnetic particles with diameters in the range of 8–15 μm is achieved. We show that the device is reliable and works well at different magnetic field strengths (50–100 Oe) and frequencies (0.05–0.5 Hz). We also employed an image processing code with a trained convolutional neural network to automate the proposed transistors for identifying and sorting particles with various sizes and magnetic susceptibilities with accuracies higher than 98%. The proposed transistors can be used in designing novel magnetophoretic circuits for important applications in biomedical microdevices and single-cell biology.

Foodborne diseases are a significant global public health concern due to their high prevalence, mortality, and economic losses. The aim of this study was to conduct a systematic review of identified foodborne pathogens and outbreaks in Iran over the past 23 years to provide an overview of the risk assessment and prevention approaches in the country. Using appropriate keywords and searching major databases, such as ScienceDirect, Scopus, PubMed, Google Scholar, and the Iranian Scientific Knowledge Database, we initially identified 4,740 articles. Finally, 328 articles were selected for evaluation. Among these articles, publications on Salmonella, Staphylococcus aureus, and Listeria were the most numerous. Poultry meat was found to be the main source of major foodborne pathogens in Iran, including Campylobacter (46.21%), Listeria monocytogenes (38.45), Salmonella (24.83%), and Yersinia enterocolitica (16.81%). Given the high prevalence of foodborne bacteria in Iranian foods, it is crucial to implement effective control measures to reduce the risk and burden of foodborne diseases. In particular, poultry meat, which poses a high risk for the occurrence of foodborne diseases in Iran, should be subjected to further risk assessment and control measures throughout the food chain.

There is currently no effective treatment strategy for recurrent/metastatic adenoid cystic carcinoma (R/M ACC). Furthermore, recent single-agent and combination immunotherapy trials have failed in unselected ACC cohorts, unlike non-ACC salivary gland cancers. Genomic profiling revealed no actionable targets but NOTCH1 and KDM6A frameshift and CTCF splice site mutations (no MYB/L fusion) with a low tumor mutational burden (TMB), microsatellite stable (MSS) and negative programmed death ligand 1 (PD-L1) were observed. We recommended an anti-programmed cell death protein 1 (anti-PD-1) plus anti-Cytotoxic T-lymphocyte-associated protein 4 (anti-CTLA-4) combination based on TMB 2-fold greater-than-median TMB in ACC, tumor harboring multiple immunogenic frameshift or splice site mutations, and PD-L1 negativity. Accordingly, we achieved a complete response in a radiotherapy (RT) and chemotherapy (CT)-refractory patient with locally recurrent lacrimal gland (LG) ACC and lung metastasis following personalized immunotherapy in combination with integrative therapeutics. Therefore, it is crucial to assess not only conventional immune biomarkers but also patient-specific parameters, especially in “immune-cold” cancer types.

Abstract Background In goat kids, choosing the appropriate age to administer the first dose of goat pox disease (GTP) vaccine requires knowing when maternal antibody decline concentrations. Objective Determine the persistence of maternal antibodies against goat pox virus (GTPV) in goat kids. Animals Twenty Saanen goat kids from birth to 120 days old. Methods In 2 groups, including: control (receiving colostrum from nonvaccinated does) and treatment (receiving colostrum from vaccinated does). On zero, 3, 7, 14, 21, 28, 42, 56, 70, 100 and 120 days after the birth, virus neutralization test was used to measure the serum concentration of antibodies against GTPV. Results At the age of 56 days, the first seronegative goat kids (n = 2) were recorded in the treatment group. At the age of 120 days, all the goat kids in the treatment group were seronegative. The average virus neutralization index (VNI) of the goat kids became negative at the age of 100 to 120 days. All goat kids in the control group were negative at all times. Conclusions and Clinical Importance One hundred to 120 days of the age seems to be the time to administer the first GTP vaccine in the goat kids with passive immunity against goat pox.

Summary: Introduction: Multiple Sclerosis (MS) is an immune-mediated central nervous system disorder, often accompanied by fatigue, which can be an initial symptom. Cocoa, rich in antioxidants like flavonoids, has previously reduced fatigue in chronic fatigue syndrome patients. This study aimed to assess cocoa's impact on fatigue in patients with relapsing-remitting MS (RRMS). Methods: This study was a double-blind, parallel placebo-controlled trial in patients with RRMS. A total number of 60 patients entered the study and were divided into intervention and control groups. The intervention group consumed 25 grams of cocoa daily, split into two 12.5-gram sachets, while the placebo group received 2.5 grams daily. Modified fatigue impact scale (MFIS) and Fatigue severity scale (FSS) questionnaires were filled at baseline, week 4, and week 8. Results: No significant changes were observed in FSS (P = 0.90) and MFIS (P = 0.37) during the interventions. No significant differences were observed in the questionnaire score changes between the two groups, except for the FSS decrease in the second four weeks (P < 0.05). FSS and MFIS were significantly correlated during different assessment times (P < 0.05). Both MFIS and FSS scores were correlated with Beck's depression inventory score. Conclusions: We indicated that FSS changed significantly after cocoa consumption in patients with RRMS. The FSS score of the cocoa group continued to decrease during the subsequent four weeks, unlike the placebo group. It appears that cocoa primarily affects physical fatigue rather than psychosocial or cognitive fatigue. While these results align with some prior studies, further research on larger populations is necessary to confirm these findings.

Objectives: The present study compared respiratory parameters between the two methods of airwayestablishment, ETT and LMA, for patients scheduled for orthopedic surgery with general anesthesia.Methods: This randomized double-blinded clinical trial was conducted on patients scheduled for electiveorthopedic surgery under general anesthesia, in Bandar Abbas, Iran, from January 2021 to December 2021.Using a random allocation table, the study participants were randomly divided into two groups, to employeither ETT (n=48) or LMA insertion (n=48). The study’s ultimate goal was to assess the respiratory parametersin 1, 3, 5, 10, and 15 minutes following intubation.Results: At all-time points, the average of peak airway pressure (P peak) and P plateau parameters in theETT group was much higher than the EMA group (p0.05).Conclusion: In terms of arterial oxygen saturation stability and at the same time providing respiratory dynamiccompliance, the LMA device outperformed the ETT.

Abstract The objective of this study was to synthesize a novel antibacterial and anticancer nanoformulation using aloe vera-derived carbon quantum dots (Cdot) and chromium-doped alumina nanoparticles (Al2O3:Cr/Cdot NPs) via a sol–gel method. X-ray diffraction (XRD) analysis confirmed crystalline NPs with a size range of 10–12 nm, while energy-dispersive X-ray spectroscopy (EDS) revealed their elemental composition without impurities. Fourier-transform infrared spectroscopy (FT-IR) indicated strong interactions between Cdot and Al2O3:Cr NPs, forming a robust heterostructure. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) images provided visual confirmation of monodisperse, spherical NPs, ensuring uniformity for further applications. Evaluation of reactive oxygen species (ROS) demonstrated superior generation of singlet oxygen and hydroxyl radicals by Al2O3:Cr/Cdot NPs, essential for photodynamic therapy. Minimum inhibitory concentration (MIC) tests revealed potent antibacterial activity against drug-resistant bacteria, inhibiting biofilm formation by 89% and 95% for MRSA and P. aeruginosa PAO1, respectively. Furthermore, the anticancer activity of Al2O3:Cr/Cdot NPs was assessed using C26 cells, demonstrating enhanced cytotoxicity upon UVA exposure. The NPs exhibited an inhibitory concentration (IC50) of 20 μg/mL without UVA exposure, decreasing to 10 μg/mL with UVA exposure, highlighting the synergistic effect of UVA light in enhancing cytotoxicity. Overall, these findings underscore the significant potential of Al2O3:Cr/Cdot NPs as multifunctional agents for addressing drug-resistant bacteria and advancing cancer therapy, offering promising avenues for nanomedicine research and development.

Abstract Aromatic compounds are known anti-amyloid aggregates. Their effect on amorphous aggregates of proteins is, however, less studied. We chose aromatic amino acids Trp, Tyr, and Phe, as well as another known stabilizer (i.e. Arg), as potential compatible solvents to be tested on Bacillus amyloliquefaciens alpha-amylase (BAA). Among these additives, Phe was the only one to be effective on the thermal inactivation and amorphous aggregation of BAA, while preserving its intrinsic activity. A concentration of 50 mM Phe was used to test its potential in counteracting the deleterious effect of BAA amorphous aggregates in vivo. After 21 days of daily subcutaneous injections of the native enzyme to mice, amorphous aggregates of BAA, as well as aggregates produced in presence of 50 mM Phe, the tissues located at the site of injection were studied histologically. Amorphous aggregates caused an increase in macrophages and lipid droplets. Serum levels of IL6 and TNF-α were also accordingly elevated and indicative of an inflammation state. Aggregates also resulted into increased levels of glucose, triglycerides and cholesterol, as well as liver enzymes SGOT and SGPT. On the other hand, the presence of Phe prevented this exacerbated inflammatory state and the subsequent impairment of biochemical parameters. In conclusion, Phe is an interesting compound for both stabilizing proteins and counteracting the pathological effect of amorphous aggregates.

Working memory plays an important role in learning since it serves as the buffer between past sensations and future behavior, making it essential to understand not only how we encode and recall sensory information in memory but also how we plan for its upcoming use. This study examined the effect of working memory training on vocabulary recall and retention of Iranian EFL learners using the dual N-back task technique. N-back requires the individual to remember an item that was presented a certain number of items previously. To this end, 50 EFL learners were randomly assigned to the experimental (n = 25) and control (n = 25) groups. The participants were taught 100 English words in 20 sessions. In each session, the experimental group also received a dual n-back task. After the treatment, immediate and delayed vocabulary posttests were administered. The obtained data were analyzed through two-way repeated-measures ANOVA and independent samples "t"-tests. The results showed that the experimental group outperformed the control group in target words' recall and retention.