Effective Area Research Articles

Study on mode properties of GaAs based hybrid plasmonic terahertz waveguide

Abstract The Terahertz (THz) field is emerging with the goal of addressing the critical challenges associated with achieving high data rates and rapid communication. In this study, a hybrid plasmonic THz waveguide has been designed and analyzed operating in 2.5-3.5 THz frequency range. The waveguide is constructed using GaAs (Gallium Arsenide) as the high refractive index core, surrounded by AlAs (Aluminium Arsenide), Ag (Silver) and placed on an HDPE (high-density polyethylene) substrate. Graphene is strategically positioned between HDPE layer to enhance light confinement. The mode properties of the designed waveguide that have been simulated using multiphysics simulations of finite element method shows unique characteristics. The observations of the simulated results at 2.5 to 3.5 THz, shows the effective refractive index of 3.79, effective mode area of 1.88 mm2, birefringence of 0.2, dispersion of 0.10 ps/THz/cm, mode field diameter of 15.8 mm, beat length of 123 mm, confinement loss 1.79 x 10-9 mm-1 has been obtained. These features make the proposed waveguide suitable for applications in photonic integrated circuits for THz communications.

Direct Affinity Ligand Immobilization onto Bare Iron Oxide Nanoparticles Enables Efficient Magnetic Separation of Antibodies.

Magnetic separation is a promising alternative to chromatography for enhancing the downstream processing (DSP) of monoclonal antibodies (mAbs). However, there is a lack of efficient magnetic particles for successful application. Aiming to fill this gap, we demonstrate the suitability of bare iron oxide nanoparticles (BION) with physical site-directed immobilization of an engineered Protein A affinity ligand (rSpA) as an innovative magnetic material. The rSpA ligand contains a short peptide tag that enables the direct and stable immobilization onto the uncoated BION surface without commonly required laborious particle activation. The resulting BION@rSpA have beneficial characteristics outperforming conventional Protein A-functionalized magnetic particles: a simple, fast, low-cost synthesis, a particle size in the nanometer range with a large effective specific surface area enabling large immunoglobulin G (IgG) binding capacity, and a high magnetophoretic velocity advantageous for fast processing. We further show rapid interactions of IgG with the easily accessible rSpA ligands. The binding of IgG to BION@rSpA is thereby highly selective and not impeded by impurity molecules in perfusion cell culture supernatant. Regarding the subsequent acidic IgG elution from BION@rSpA@IgG, we observed a hampering pH increase caused by the protonation of large iron oxide surfaces after concentrating the particles in 100 mM sodium acetate buffer. However, the pH can be stabilized by adding 50 mM glycine to the elution buffer, resulting in recoveries above 85% even at high particle concentrations. Our work shows that BION@rSpA enable efficient magnetic mAb separation and could help to overcome emerging bottlenecks in DSP.

The SRG/eROSITA All-Sky Survey: SRG/eROSITA cross-calibration with Chandra and XMM-Newton using galaxy cluster gas temperatures

Galaxy cluster gas temperatures ($T$) play a crucial role in many cosmological and astrophysical studies. However, it has been shown that $T$ measurements can significantly vary between different X-ray telescopes. These $T$ biases can propagate to several cluster applications in which $T$ can be used, such as measuring hydrostatic cluster masses and constraining the angular variation of cosmological parameters. Thus, it is important to accurately cross-calibrate X-ray instruments to account for systematic biases. In this work, we present the cross-calibration between Spectrum Roentgen Gamma/eROSITA (SRG/eROSITA) and Chandra /ACIS and between SRG/eROSITA and XMM-Newton /EPIC using for the first time a large sample of galaxy cluster $T$. To do so, we used the first eROSITA All-Sky Survey data and the preliminary extremely expanded HIgh FLUx Galaxy Cluster Sample, a large X-ray flux-limited cluster catalog. We spectroscopically measured X-ray $T$ for 186 independent cluster regions with both SRG/eROSITA and Chandra /ACIS in a self-consistent way for three energy bands: 0.7-7 keV (full), 0.5-4 keV (soft), and 1.5-7 keV (hard). We did the same with SRG/eROSITA and XMM-Newton /EPIC for 71 different cluster regions and all three bands. We find that SRG/eROSITA measures systematically lower $T$ than the other two instruments, with hotter clusters deviating more than cooler ones. For the full band, SRG/eROSITA returns 20$<!PCT!>$ and 14$<!PCT!>$ lower $T$ than Chandra /ACIS and XMM-Newton /EPIC, respectively, when the two other instruments each measure $k_ B T 3$ keV. The discrepancy respectively increases to 38<!PCT!> and 32<!PCT!> when Chandra /ACIS and XMM-Newton /EPIC each measure $k_ B T 10$ keV. On the other hand, the discrepancy becomes milder for low-$T$ galaxy groups. Moreover, a broken power law fit demonstrated that there is a break at the SRG/eROSITA- Chandra /ACIS scaling relation at $k_ B T 1.7-2.7$ keV, depending on the energy band. The soft band shows a marginally lower discrepancy compared to the full band. In the hard band, the cross-calibration of SRG/eROSITA and the other instruments show very strong differences. We tested several possible systematic biases (such as multiphase cluster gas, Galactic absorption, non-Gaussian scatter, and selection effects) to identify the reason behind the cross-calibration discrepancies, but none could significantly alleviate the tension. For now, it is most likely that the systematically lower SRG/eROSITA $T$ can be attributed to systematic effective area calibration uncertainties; however, the exact role of multiphase cluster gas in the observed $T$ discrepancies needs to be further investigated. Furthermore, we provide conversion factors between SRG/eROSITA Chandra /ACIS, and XMM-Newton /EPIC $T$ that will be beneficial for future cluster studies that combine SRG/eROSITA $T$ with data from other X-ray instruments. Finally, we also provide conversion functions between the official eRASS1 cluster catalog $T$ and the equivalent core and core-excised Chandra /ACIS and XMM-Newton /EPIC $T$.

Plant-based zinc nanoflowers assisted molecularly imprinted polymer for the design of an electrochemical sensor for selective determination of abrocitinib

The first electrochemical sensor application in the literature is described for the sensitive and selective determination of the selective Janus kinase (JAK)-1 inhibitor abrocitinib (ABR). ABR is approved by the U.S. Food and Drug Administration (FDA) for the treatment of atopic dermatitis. The molecularly imprinted polymer (MIP)-based sensor was designed to incorporate zinc nanoflower (ZnNFs)-graphene oxide (GO) conjugate (ZnNFs@GO), synthesized from the root methanolic extract (RME) of the species Alkanna cappadocica Boiss. et Bal. to improve the porosity and effective surface area of the glassy carbon electrode (GCE). Furthermore, the MIP structure was prepared using ABR as a template molecule, 4-aminobenzoic acid (4-ABA) as a functional monomer, and other additional components. Scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR) were used to characterize the surface and structure of the synthesized nanomaterial and MIP-based surface. Among the electrochemical methods, cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) were preferred for detailed electrochemical characterization, and differential pulse voltammetry (DPV) was preferred for all other electrochemical measurements using 5.0 mM [Fe(CN)6]3–/4– solution as the redox probe. The MIP-based sensor, which was the result of a detailed optimization phase, gave a linear response in the 1.0 × 10–13 – 1.0 × 10–12 M range in standard solution and serum sample. The obtained limit of detection (LOD) and limit of quantification (LOQ) values and recovery studies demonstrated the sensitivity, accuracy, and applicability of the sensor. Selectivity, the most important feature of the MIP-based sensor, was verified by imprinting factor calculations using ibrutinib, ruxolitinib, tofacitinib, zonisamide, and acetazolamide.Graphical

Gold nanosheet modified electrode with reduced impedance for electrophysiological recordings

In neurophysiological recording, reducing electrode impedance is crucial for enhancing the signal-to-noise ratio and achieving the desired spatial resolution. This study presents an approach to improve the performance of Au/Cr/glass electrodes by incorporating synthesized gold nanosheets without the need for additional adhesive material. We characterized the performance of the modified electrodes using electrochemical impedance spectroscopy and equivalent circuit analysis. Our findings showed an 81% reduction in mean impedance for the modified electrode, which was 0.85 kΩ at 1 kHz, compared to the unmodified electrode at 4.5 kΩ, an improvement attributed to the higher effective surface area of the modified electrode. Additionally, Scanning electron microscopy observations of PC12 cells cultured on the modified electrodes indicated favorable cell elongation and interaction with the rough surface. Stability studies indicated acceptable performance of the modified electrodes in solution environments. These results suggest that surface modification of electrodes with gold nanosheets could be a promising strategy for enhancing neural interface applications.

Two-dimensional quantum droplets in binary quadrupolar condensates

Abstract We study the stability and characteristics of two-dimensional (2D) quasi-isotropic quantum droplets (QDs) of fundamental and vortex types, formed by binary Bose-Einstein condensate with magnetic quadrupole-quadrupole interactions (MQQIs). The magnetic quadrupoles are built as pairs of dipoles and antidipoles polarized along the x-axis. The MQQIs are induced by applying an external magnetic field that varies along the x-axis. The system is modeled by the Gross-Pitaevskii equations including the MQQIs and Lee-Huang-Yang correction to the mean-field approximation. Stable 2D fundamental QDs and quasi-isotropic vortex QDs with topological charges S ≤ 4 are produced by means of the imaginary-time-integration method for configurations with the quadrupoles polarized parallel to the system’s two-dimensional plane. Effects of the norm and MQQI strength on the QDs are studied in detail. Some results, including an accurate prediction of the effective area, chemical potential, and peak density of QDs, are obtained in an analytical form by means of the Thomas-Fermi approximation. Collisions between moving QDs are studied by means of systematic simulations.

Research of biomimetic corrugation on the blade flutter suppression in large-scale wind turbine systems

Abstract Aiming at the blade flutter of large horizontal-axis wind turbines, a method by utilizing biomimetic corrugation to suppress blade flutter is first proposed. By extracting the dragonfly wing corrugation, the biomimetic corrugation airfoil is constructed, finding that mapping corrugation to the airfoil pressure side has better aerodynamic performance. The influence of corrugation type, amplitude λ, and intensity on airfoil flutter is analyzed using orthogonal experiment, which determines that the λ has the greatest influence on airfoil flutter. Based on the drag coefficient flutter index δ, the optimal airfoil flutter suppression effect is obtained when the type is III, λ=0.6, and intensity is denser (n=13). The effective corrugation layout area in the chord direction is determined to be the leading edge, and the δ of corrugation airfoil is reduced by 5.049%, compared to the original airfoil. The application of this corrugation to NREL 15 MW wind turbine 3D blades is studied, and the influence of corrugation layout length in the blade span direction on the suppressive effect is analyzed by fluid-structure interaction. It is found that when the layout length is 0.85R, the safety margin Sf reaches a maximum value of 0.3431 Hz, which is increased 2.940%. The results show that the biomimetic corrugated structure proposed in this paper can not only improve the aerodynamic performance by changing the local flow field on the surface of the blade, but also increase the structural stiffness of the blade itself, and achieve the effect of flutter suppression.

Numerical Analysis of Optical Properties Using Octagonal Shaped Ge15As15Se17Te53 Chalcogenide Photonic Crystal Fiber

A novel Ge15As15Se17Te53 chalcogenide-based photonic crystal fiber with an octagonal cladding was designed which exhibits low confinement loss and high nonlinearity. The dispersion properties were investigated over a wide wavelength range of up to 11 µm. Based on preliminary simulation results, three fibers with suitable characteristic quantities are proposed for supercontinuum generation. Among these fibers, fiber #F1 (Ʌ = 3.1 µm, d/Ʌ = 0.3) exhibits all-normal dispersion with a small value of −0.374 ps/[nm.km]. At the same time, the highest nonlinear coefficient of 2876.861 W−1.km−1 at the pump wavelength of 5.45 µm is also found. The #F2 fiber (Ʌ= 4.5 µm, d/Ʌ = 0.3) has anomalous flat dispersion with one zero dispersion wavelength. This fiber has the smallest dispersion and lowest confinement loss values of 0.281 ps/[nm.km] and 1.360×10−9 at 5.7 µm pump wavelength, respectively. With the anomalous dispersion, #F3 fiber (Ʌ = 3.5 µm, d/Ʌ = 0.3) offers a small effective mode area of 20.892 µm2 and a low confinement loss of 4.974×10−8 dB/m at 5.25 µm wavelength. The proposed fibers can be a low peak power, broadband supercontinuum source, suitable for application fields such as optical communication and biomedical sensors.

Verified of leakage loss, birefringence, nonlinear parameters and total number of modes in silica/silica doped and plastic fibers for fiber system efficiency improvement

Abstract This paper has clarified verified of leakage loss, birefringence, nonlinear parameters and total number of modes in silica/silica doped and plastic fibers for fiber system efficiency improvement. The signal power loss is demonstrated with silica/silica doped/plastic fibers at various ambient temperatures. The estimated number of fiber modes is clarified in the core against silica/silica doped/plastic fiber core radius. The fiber birefringence is studied against silica/silica doped/plastic fiber core radius. The silica/silica doped/plastic fibers effective refractive index is clarified versus ambient temperature variations. The nonlinear parameter is demonstrated based silica doped fiber against the dopant concentration ratio with different temperature variations. The effective area cross section is studied based silica doped fiber against the dopant concentration ratio with different temperature variations. The predicted fiber loss is demonstrated against the fiber operating wavelength for silica glass fibers/silica doped fibers/plastic fibers. As well as the predicted fiber loss is clarified and studied versus fiber core radius for silica glass/silica doped/plastic fibers.

Dividing active and passive particles in nonuniform nutrient environments

Abstract To explore the coupling between a growing population of microorganisms such as E. coli and a nonuniform nutrient distribution, we formulate a minimalistic model. It consists of active Brownian particles that divide and grow at a nutrient-dependent rate following the Monod equation. The nutrient concentration obeys a diffusion equation with a consumption term and a point source. In this setting the heterogeneity in the nutrient distribution can be tuned by the diffusion coefficient. 

In particle-based simulations, we demonstrate that passive and weakly active particles form proliferation-induced clusters when the nutrient is localized, without relying on further mechanisms such as chemotaxis or adhesion. In contrast, strongly active particles disperse in the whole system during their lifetime and no clustering is present. The steady population is unaffected by activity or nonuniform nutrient distribution and only determined by the ratio of nutrient influx and bacterial death. However, the transient dynamics strongly depends on the nutrient distribution and activity. Passive particles in almost uniform nutrient profiles display a strong population overshoot, with clusters forming all over the system. In contrast, when slowly diffusing nutrients remain centred around the source, the bacterial population quickly approaches the steady state due to its strong coupling to the nutrient. Conversely, the population overshoot of highly active particles becomes stronger when the nutrient localisation increases. We successfully map the transient population dynamics onto a uniform model where the effect of the nonuniform nutrient and bacterial distributions are rationalized by two effective areas.

Active Adaptive Strategies of Mallard Feet in Response to Changes in Wetness and Compactness of the Sand Terrain.

Mallards (Anas platyrhynchos) exhibit exceptional locomotive abilities in diverse terrains, such as beaches, swamps, and tidal flats. This capability is primarily attributed to their unique webbed toe structure and cooperative locomotion posture of their feet. Therefore, this study aims to further delve into the active adaptive strategies of mallard feet in response to diverse external environmental conditions. Six adult male mallards were selected for this research. Their locomotion on sandy surfaces with differing wetness levels and varying degrees of compaction were captured using a high-speed camera, and analysis of instantaneous and continuous changes in the primary joint angles of the mallards' feet, including the toe-webbed opening and closing angles, the tarsometatarsal-phalangeal joint (TMTPJ), and the intertarsal joint (ITJ). It was found that on loose sandy surfaces, increasing wetness expanded the ground contact area of the mallards' feet. This led to greater flexion at the TMTPJ joint during mid-stance, accompanied by decreased flexion of the ITJ during touch-down and mid-stance. Conversely, on compacted sand, increasing wetness resulted in a reduced foot effect area and lessened ITJ flexion at both touch-down and mid-stance. Furthermore, on looser sand, the ground contact area of the mallards' feet decreased, with an increase in ITJ buckling at touch-down. During the swing phase, sand wetness and compactness effected minimally on the feet of the mallards. On dry and loose sand ground, mallards will contract their second and fourth toes with webbing upon ground contact, covering and compacting the sand beneath while increasing ITJ flexion to mitigate sinking. This adaptation reduces the energy expended on sand and enhances body stability. In wet and compacted sand conditions, mallards expand their second and fourth toes upon ground contact and reduce ITJ flexion. Therefore, this coordinated foot and ITJ locomotion offers mallards a natural advantage when moving on various environmental media.

Understanding the effects of climate and anthropogenic stresses on distribution variability of Setipinna taty in the Yellow Sea

Setipinna taty is one of the pivotal fishes in the Yellow Sea large marine ecosystem, and detecting and analyzing changes in the patterns of its distribution under multiple stresses is important in understanding its population dynamics and potential shifts in its ecological role. In this study, eight alternative spatio-temporal models were developed for S. taty using the Vector Autoregressive Spatio-Temporal (VAST) framework to analyse winter trawl survey data in the Yellow Sea from 2001–2021. These models included different combinations of local sea temperature, climate index and fishing pressure as explanatory variables. The model selected, based on Akaike's Information Criterion (AIC) and spatio-temporal variation explanation rate, indicated that the spatio-temporal distribution patterns of the population were driven by a combination of local temperature, climatic pressure, and fishing intensity. Among these factors, sea temperature is purportedly the most important driver. Results from the chosen model showed that the effective area occupied by the population decreased significantly during the study period (p<0.05). Prior to 2010, the climate and marine environment were relatively stable, and distribution changes were consistent with the basin model (BM, supported by density-dependent habitat selection theory), that individuals move to preferred habitats as biomass declines under fishing pressure (i.e. S. taty individuals were concentrated within the core distribution area as biomass declines). The climate and its driving oceanographic conditions (temperature) changed significantly after 2010 and, as a result, population distribution changes became complex (non-significant relationship between abundance and distribution area) and were no longer supported by BM, corresponding to a significant northward shift of the center of gravity (p<0.05) and a northward expansion of the northern population boundary. Our study highlights the synergistic drive of multiple stresses on spatio-temporal distribution patterns of the S. taty population. Future research should focus on developing a mechanistic understanding of the synergies between climate and anthropogenic stresses and how they affect population dynamics (distribution patterns), which is key to the successful management of the S. taty fishery and other fisheries in this ecosystem.

Examining the typical hemodynamic performance of nearly 3000 modern surgical aortic bioprostheses.

The objective of this analysis was to assess the normal haemodynamic performance of contemporary surgical aortic valves at 1 year postimplant in patients undergoing surgical aortic valve replacement (SAVR) for significant valvular dysfunction. By pooling data from four multicentre studies, this study will contribute to a better understanding of the effectiveness of SAVR procedures, aiding clinicians and researchers in making informed decisions regarding valve selection and patient management. Echocardiograms were assessed by a single core laboratory. Effective orifice area (EOA), dimensionless velocity index (DVI), mean aortic gradient, peak aortic velocity, and stroke volume were evaluated. The cohort included 2958 patients. Baseline age in the studies ranged from 70.1 ± 9.0 to 83.3 ± 6.4 years, and STS risk of mortality was 1.9 ± 0.7 to 7.5 ± 3.4%. Twenty patients who had received a valve model implanted in fewer than 10 cases were excluded. Ten valve models (all tissue valves; N = 2938 patients) were analyzed. At 1 year, population mean EOA ranged from 1.46 ± 0.34 to 2.12 ± 0.59 cm2, and DVI, from 0.39 ± 0.07 to 0.56 ± 0.15. The mean gradient ranged from 8.6 ± 3.4 to 16.1 ± 6.2 mmHg with peak aortic velocity of 1.96 ± 0.39 to 2.65 ± 0.47 m/s. Stroke volume was 75.3 ± 19.6 to 89.8 ± 24.3 mL. This pooled cohort is the largest to date of contemporary surgical aortic valves with echocardiograms analyzed by a single core lab. Overall haemodynamic performance at 1 year ranged from good to excellent. These data can serve as a benchmark for other studies and may be useful to evaluate the performance of bioprosthetic surgical valves over time.

Albumin-derived perfluorodecalin-based hybrid systems with developed effective surfaces aimed at biomedical application

The study aims to approach a coating layer based on alginate functionalized with albumin nanocoated oxygenating factor, constituting a safe and even contact surface with epithelial cells in system components for medical devices to support maintaining the human lung cells’ function. The alginate coating layer with incorporated albumin-coated oxygenating element was designed (ALG_Alb-PFD). As an oxygenating factor, perfluorodecalin was applied at three saturation levels with oxygen: 0%, 21%, and 100%. The studies were performed on human adenocarcinoma A549 cell lines derived from human lung epithelial cells cultured in configuration with the designed coatings. Scanning electron microscopy, flow cytometry, and fluorescence microscopy were applied to evaluate cell function and the system morphology. AFM and SEM-EDX characterized the coating layer material. The designed coating ensured the viability of human lung cells cultured on the coating layer during 10 days of culture. An oxygenating factor presence was confirmed by SEM-EDX analysis of the ALG_Alb-PFD. However, no significant discrepancies were noted between the coatings with different saturation levels after 10 days of culture. Moreover, the AFM-analyzed profiles of the coating surface confirmed/indicated the formation of additional elements in the coating due to using an oxygenating element, which increases the effective contact area with cells. The platform based on alginate with the developed surface of contact of oxygenating factor incorporated within the coating layer ensures the sustained growth and morphology of the human lung cells, which can be considered a therapeutic element of system components of medical devices for maintaining human lung cells’ function.

Dynamic healing-assembly for biocompatible, biodegradable, stretchable and self-healing triboelectric nanogenerators

Triboelectric nanogenerators (TENGs) have great potential as power sources for on-skin and implantable electronics. However, most existing TENGs are not suitable for the above applications due to limited material choices, often characterized by rigidity, susceptibility to damage, biological incompatibility, and non-biodegradability. Herein, we developed a simple self-healing assembly strategy based on introducing dynamic Cu(II)-dimethylglyoxime-urethane groups into a biocompatible and biodegradable polyurethane elastomer, to simultaneously address the above obstacles. The coordination of Cu2+ with dynamic bonds significantly enhanced the mechanical properties of elastomer, resulting in a modulus of 9.4 MPa and toughness of 40.2 MJ/m3. These bonds also gave the elastomer skin-like self-healing capabilities, achieving a healing efficiency of 77.5 % at 80 °C. Subsequently, a highly stretchable and integrated triboelectric nanogenerator (Cu-POU TENG) with self-healing capabilities was developed. The Cu-POU TENG with an effective area of 1.5 × 1.5 cm2 produced an open-circuit voltage of 38 V in single-electrode mode. The Cu-POU TENG could restore its original electrical properties through self-healing after mechanical damage. Furthermore, the Cu-POU TENG exhibited biocompatibility and biodegradability, making it suitable for on-skin and implantable electronics. Notably, the Cu-POU TENG maintained a stable voltage output throughout the degradation process. The integration of self-healing feature enabled a sophisticated structure, allowing the Cu-POU TENG to function effectively as a motion sensor for tracking body movement. This Cu-POU TENG holds great potential for applications in on-skin and implantable electronics.

Broadband dispersion compensation and high birefringence photonic crystal fiber for CWDM/DWDM networks

In this study, we propose a new design based on photonic crystal fibers (PCFs) for broadband dispersion compensation in telecommunication networks. The proposed design has a hexagonal structure arrangement of air-holes rings of different diameters between the silica core and the cladding. The PCF properties like effective area, nonlinearity, dispersion slope, confinement loss, and birefringence are reported and discussed. For the best performance we present three designs A, B and C. Simulation results show that the three designs cover the six-telecommunication optical bands O-, E-, S-, C-, L- and U- bands (wavelengths ranging from 1260 to 1675 nm). Design A achieves a large negative dispersion value of about − 1716 ps/(nm.km) with relative dispersion slope equals to that of conventional single-mode optical fibers (SMFs) of about 0.0036 nm−1, which makes it very suitable for long-haul DWDM transmission systems. With a little modification in the core, designs B and C achieve much higher confinement ability and achieve a very large birefringence value for polarization mode dispersion and sensing applications. Design C is engineered to have exact opposite dispersion of SMF with zero dispersion at the wavelength 1310 nm, which makes it a promising design in CWDM transmission system. The numerical values have been investigated using the full vector finite element method.

Probabilistic stimulation mapping from intra-operative thalamic deep brain stimulation data in essential tremor.

Deep brain stimulation (DBS) is a therapy for Parkinson's disease (PD) and essential tremor (ET). The mechanism of action of DBS is still incompletely understood. Retrospective group analysis of intra-operative data recorded from ET patients implanted in the ventral intermediate nucleus of the thalamus (Vim) is rare. Intra-operative stimulation tests generate rich data and their use in group analysis has not yet been explored. &#xD;&#xD;Objective: To implement, evaluate, and apply a group analysis workflow to generate probabilistic stimulation maps (PSM) using intra-operative stimulation data from ET patients implanted in Vim. &#xD;&#xD;A group-specific anatomical template was constructed based on the Magnetic Resonance Imaging (MRI) scans of 6 ET patients and 13 PD patients. Intra-operative test data (total: n=1821) from the 6 ET patients was analyzed: patient-specific electric field simulations together with tremor assessments obtained by a wrist-based acceleration sensor were transferred to this template. Occurrence and weighted mean maps were generated. Voxels associated with symptomatic response were identified through a linear mixed model approach to form a PSM. Improvements predicted by the PSM were compared to those clinically assessed. Finally, the PSM clusters were compared to those obtained in a multicenter study using data from chronic stimulation effects in ET. &#xD;&#xD;Regions responsible for improvement identified on the PSM were in the posterior sub-thalamic area (PSA) and at the border between the Vim and ventro-oral nucleus of the thalamus (VO). The comparison with literature revealed a center-to-center distance of less than 5mm and an overlap score (Dice) of 0.4 between the significant clusters. &#xD;&#xD;Our workflow and intra-operative test data from 6 ET-Vim patients identified effective stimulation areas in PSA and around Vim and VO, affirming existing medical literature. This study supports the potential of probabilistic analysis of intra-operative stimulation test data to reveal DBS's action mechanisms and to assist surgical planning.

Halophiles and their adaptations: A comprehensive review on recent progress and prospects in biodesalination applications

AbstractWorldwide climate change, rising population, and industrialization have raised the global demand for freshwater. Desalinating brackish water has become a sustainable technology for drinking and agriculture to overcome global water scarcity. Thriving biodesalination technology has become more attractive and eco‐friendly than the present physicochemical desalination methods, which are expensive and energy‐intensive. Researchers are exploring the bioutilization of nature's potential for desalination using halophiles like haloarchaea, halobacteria, halophytic algae, and plants. Biomimetic desalination membranes have been developed, inspired by the desalination mechanism in animals. This comprehensive review explores recent advancements and potential applications of halophiles in biodesalination to exploit them effectively. It provides an overview of the opportunities and challenges associated with harnessing halophiles for the removal of salts from brackish and seawater sources. This review also focuses on insights into biomolecules produced by the halophilic microorganisms and halophytes in the desalination process. Understanding the mechanism of action of these biomolecules will edify the effective unexplored research areas in biomimicry and bioutilization to overcome the existing limitations in water treatment.

First integration of Ni barrier layer for enhanced threshold switching characteristics in Ag/HfO2-based TS device

Utilizing Ag/HfO2 with nickel (Ni) as a barrier layer, a novel threshold switching (TS) device is devised to overcome challenges such as low reliability, high threshold voltage, and high leakage current. Compared against an Ag/Ti/HfO2-based TS device, the Ag/Ni/HfO2-based TS device exhibits improved electrical characteristics: yield enhancement from 31.7 % to 40.0 %, enhanced endurance from ∼10 cycles to ∼300 cycles, and suppression in off-state current (IOFF) from 1.2 × 10−7 A to 5.2 × 10−10 A under a high compliance current (e.g., 10−4 A). The results obtained through transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDS), and atomic force microscopy (AFM) support the evidence of those accomplishments. Reducing the effective area of the TS device improves control over erratically generated filaments and the electric field within the switching layer, resulting in enhanced performance such as a reduced threshold voltage (VTH ∼0.35 V), minimized VTH variability (∼0.01 V), decreased a threshold current (ITH, i.e., the leakage current in the off-state before activation, ∼5.2 × 10−10 A), and maximum conductance (∼5.0 × 10−5 S) of low-resistance state. These findings suggest that the optimized Ag/Ni/HfO2-based TS device can serve as a practical solution for low-power applications.

Investigation of microfriction properties of graphene/AlCoCrFeNi high entropy alloy

Applying graphene (Gr) coatings to high-entropy alloys (HEA) is anticipated to enhance their tribological characteristics. The current understanding of the mechanism by which the Gr/HEA is enhanced at the atomic level is still limited. Molecular dynamics simulations revealed the mechanical behavior and strengthening mechanism of the Gr/AlCoCrFeNi HEA during nanoindentation and nanoscratch. The results demonstrate a substantial increase in the indentation hardness of the Gr/AlCoCrFeNi HEA by about 2.4 times. When Gr changed from a single layer to three layers, it further improved (3.2 times for a double layer and 3.9 times for three layers). At the same time, the friction coefficient is effectively reduced. Furthermore, the elevated in-plane stiffness of the Gr coating leads to an expansion of the effective loading area, resulting in increased Shockley dislocation and stair-rod dislocation density within the Gr/AlCoCrFeNi HEA, thereby amplifying the strain hardening effect and reducing subsurface damage. Qualitative experiments confirmed the excellent wear resistance of the Gr/HEA, and coating Gr increased the width of scratches, effectively confirming our simulation results. These findings provide valuable insights for the development and design of Gr/HEA composite coatings with enhanced mechanical properties.