Slope Values Research Articles

Microstructure and Thermal Cyclic Behavior of FeNiCoAlTaB High-Entropy Alloy

This study investigates the grain morphology, microstructure, magnetic properties and shape memory properties of an Fe41.265Ni28.2Co17Al11Ta2.5B0.04 (at%) high-entropy alloy (HEA) cold-rolled to 98%. The EBSD results show that the texture intensities of the samples annealed at 1300 °C for 0.5 or 1 h are 2.45 and 2.82, respectively. This indicates that both samples were formed without any strong texture. The grain morphology results show that the grain size increased from 356.8 to 504.6 μm when the annealing time was increased from 0.5 to 1 h. The large grain size improved the recoverable strain due to a reduction in the grain constraint. As a result, annealing was carried out at 1300 °C/1 h for the remainder of the study. The hardness decreased at 24 h, then increased again at 48 h; this phenomenon was related to the austenite finish temperature. Thermo-magnetic analysis revealed that the austenite finish temperature increased when the samples were aged at 600 °C for between 12 and 24 h. When the aging time was prolonged to 48 h, the austenite finish temperature value decreased. X-ray diffraction (XRD) demonstrated that the peak of the precipitates emerged and intensified when the aging time was increased from 12 to 24 h at 600 °C. From the three-point bending shape memory test, the samples aged at 600 °C for 12 and 24 h had maximum recoverable strains of 2% and 3.6%, respectively. The stress–temperature slopes of the austenite finish temperature were 10.3 MPa/°C for 12 h and 6 MPa/°C for 24 h, respectively. Higher slope values correspond to lower recoverable strains.

Feasibility of indocyanine green fluorescence imaging to predict biliary complications in living donor liver transplantation: A pilot study.

Liver transplantation (LT) is now a critical, life-saving treatment for patients with liver cirrhosis or hepatocellular carcinoma. Despite its significant benefits, biliary complications (BCs) continue to be a major cause of postoperative morbidity. This study evaluates the fluorescence intensity (FI) of the common bile duct (CBD) utilizing near-infrared indocyanine green (ICG) imaging, and examines its association with the incidence of BCs within three months post-LT. This investigation analyzed data from nine living donor LT (LDLT) recipients who were administered 0.05 mg/kg of ICG prior to bile duct anastomosis. Real-time perfusion of the CBD was recorded for three minutes using an ICG camera, and FI was quantified using Image J (National Institutes of Health). Key parameters assessed included F max, F1/2 max, T1/2 max, and the slope (F max/T max) to evaluate the fluorescence response. BCs occurred in two out of nine patients. These two patients exhibited the longest T1/2 max values, which were linked with lower slope values, implicating a potential relationship between extended T1/2 max, reduced slope, and the occurrence of postoperative BCs. The study indicates that ICG fluorescence imaging may serve as an effective tool for assessing bile duct perfusion in LDLT patients. While the data suggest that an extended T1/2 max and lower slope may correlate with an increased risk of BCs, further validation through larger studies is required to confirm the predictive value of ICG fluorescence imaging in this setting.

Effects of Topography on Vegetation Coverage Changes in Rural Areas Under Multi-scale Scenarios

Revealing the characteristics of vegetation coverage change and the effects of topography on vegetation coverage change in rural areas since the reform and opening up has direct implications for further understanding of human-land coupling processes and resource and environmental changes and provides a reference for ecological environment protection in rural revitalization. Using the Taihua Town in Yixing City, Jiangsu Province, as a rural case study, we revealed the basic features of rural vegetation coverage change from 1986 to 2020. Furthermore, using 0.25 km2（scenario 1）, 0.50 km2（scenario 2）, and 1.00 km2 （scenario 3） as scale scenarios in the study area, both the single and comprehensive topographic effects on vegetation coverage change were explored. The study produced several important results： ① Vegetation coverage in the study area generally maintained an upward trend from 1986 to 2020, during which the spatial pattern of vegetation coverage distribution was generally high in the southeast and southwest and low in the north （northwest）. During this period, the vegetation coverage in the study area increased from 74.15% to 83.44%, and the spatial pattern of vegetation coverage distribution generally remained similar. ② Under the multi-scale scenarios, the vegetation coverage distribution in the study area generally maintained a similar spatial pattern from 1986 to 2020, excepting a few local differences. Under the same-scale scenario, Moran's index of vegetation coverage in the study area was higher in 2020 than in 1986. Taking scenario 1 as an example, Moran's index of vegetation coverage in the study area increased from 0.603 to 0.652 between 1986 and 2020. ③ Under the multi-scale scenarios, from 1986 to 2020, vegetation coverage in the study area generally maintained an upward trend with increase of elevation, slope, and topographic relief. As an example of the vegetation coverage change with elevation, in scenario 1 in 2020, the vegetation coverage in the study area increased from 64.50% in the area with elevations of 0-50 m to 98.77% in the area with elevations above 350 m. ④ Under the multi-scale scenarios, the comprehensive topographic effects on mean vegetation coverage change in the study area from 1986 to 2020 showed that elevation, slope, and topographic relief all had positive effects, and their effects were greater in scenario 3 than in scenario 2 and then in scenario 1 for the same topographic factor. According to the comprehensive topographic effects on mean vegetation coverage change in the study area from 1986 to 2020, the equation simulation coefficients of elevation under scenarios 1, 2, and 3 were 0.271, 0.281, and 0.283, respectively. The respective slope values were 0.283, 0.289, and 0.294, and the topographic relief values were 0.283, 0.292, and 0.295. This suggests that the scale variation has impacts on the comprehensive topographic effects. The results of this study are valuable for understanding the changes in the rural ecological environment under multi-scale scenarios since the reform and opening up.

Boosting the Performance of Alkaline Anion Exchange Membrane Water Electrolyzer with Vanadium-Doped NiFe2O4.

Developing efficient, economical, and stable catalysts for the oxygen evolution reaction is pivotal for producing large-scale green hydrogen in the future. Herein, a vanadium-doped nickel-iron oxide supported on nickel foam (V-NiFe2O4/NF) is introduced, and synthesized via a facile hydrothermal method as a highly efficient electrocatalyst for water electrolysis. X-ray photoelectron and absorption spectroscopies reveal a synergistic interaction between the vanadium dopant and nickel/iron in the host material, which tunes the electronic structure of NiFe2O4 to increase the number of electrochemically active sites. The V-NiFe2O4/NF electrode exhibited superior electrochemical performance, with a low overpotential of 186mV at a current density of 10mAcm-2, a Tafel slope value of 54.45mV dec-1, and minimal charge transfer resistance. Employing the V-NiFe2O4/NF electrode as an anode in an alkaline anion exchange membrane water electrolyzer single-cell, a cell voltage of 1.711V is required to achieve a high current density of 1.0 Acm-2. Remarkably, the cell delivered an energy conversion efficiency of 73.30% with enduring stability, making it a promising candidate for industrial applications.

Personalized auricular vagus nerve stimulation: beat-to-beat deceleration dominates in systole-gated stimulation during inspiration - a pilot study

Neuromodulation comes into focus as a non-pharmacological therapy with the vagus nerve as modulation target. The auricular vagus nerve stimulation (aVNS) has emerged to treat chronic diseases while re-establishing the sympathovagal balance and activating parasympathetic anti-inflammatory pathways. aVNS leads still to over and under-stimulation and is limited in therapeutic efficiency. A potential avenue is personalization of aVNS based on time-varying cardiorespiratory rhythms of the human body. In the pilot study, we propose personalized cardiac-gated aVNS and evaluate its effects on the instantaneous beat-to-beat intervals (RR intervals). Modulation of RR is expected to reveal the aVNS efficiency since the efferent cardiac branch of the stimulated afferent vagus nerve governs the instantaneous RR. Five healthy subjects were subjected to aVNS. Each subject underwent two 25-min sessions. The first session started with the non-gated open-loop aVNS, followed by the systole-gated closed-loop aVNS, then the non-gated, diastole-gated, and non-gated aVNS, each for 5min. In the second session, systole and diastole gated aVNS were interchanged. Changes in RR are analysed by comparing the prolongation of RR intervals with respect to the proceeding RR interval where aVNS took place. These RR changes are considered as a function of the personalized stimulation onset, the stimulation angle starting with R peak. The influence of the respiration phases is considered on the cardiovagal modulation. The results show that the systole-gated aVNS tends to prolong and shorten RR when stimulated after and before the R peak, respectively. The later in time is the stimulation onset within the diastole-gated aVNS, the longer tends to be the subsequent RR interval. The tendency of the RR prolongation raises with increasing stimulation angle and then gradually levels off with increasing delay of the considered RR interval from the one where aVNS took place. The slope of this rise is larger for the systole-gated than diastole-gated aVNS. When considering individual respiration phases, the inspiratory systole-gated aVNS seems to show the largest slope values and thus the largest cardiovagal modulatory capacity of the personalized time-gated aVNS. This pilot study indicates aVNS capacity to modulate the heartbeat and thus the parasympathetic activity which is attenuated in chronic diseases. The modulation is highest for the systole-gated aVNS during inspiration.

Endurable IGZO/SnSx/IGZO Heterojunction Phototransistor Arrays for Image Sensors.

Optoelectronic devices require stable operation to detect repetitive visual information. In this study, endurable arrays based on heterojunction phototransistors composed of indium-gallium-zinc oxide (IGZO) with a low dark current and tin sulfide (SnSx) capable of absorbing visible light are developed for image sensors. The tandem structure of IGZO/SnSx/IGZO (ISI) enables stable operation under repetitive exposure to visible light by improving the transport ability of the photoexcited carriers through mitigated trap sites and their separation into each IGZO layer. Additionally, the structure promotes recombination by confining the holes. Therefore, the optimal ISI phototransistors exhibit a photoresponsivity of 514.50 A/W and a detectivity of 1.31 × 109 Jones under red light (635 nm) of 1 mW/mm2 and endurable time-dependent photoresponse characteristics, including a slope value of 1.66 × 10-11, without the persistent photoconductivity phenomenon under green light (532 nm) at a frequency of 50 mHz for over 4,000 s. Furthermore, image sensing characteristics of the 6 × 6 arrays based on ISI phototransistors for image sensors are demonstrated by sequentially applying "4" and "2" digit numbers. These technologies contribute to the development of endurable oxide-based optoelectronic devices and provide valuable perspectives on the utility of next-generation image sensors.

Kinetics of the effect of the auricular heart point on the pressure-volume curve of the digital pulse

Introduction: The Heart auricular point has been shown to modify the characteristics of the digital pulse wave experimentally. However, kinetic studies have yet to widely evaluate its cardiovascular effects. The objective of this study was to propose an acukinetic model of the Heart auricular point effect using polynomial linear interpolation or spline. Methods: The digital volume pulse was recorded in healthy subjects. A photoplethysmography transducer was placed on the index finger of the right hand. The signal was modulated and amplified using the MP150 amplifier processor. A continuous 70-s recording was taken consisting of a 30-s baseline (1–30 s), a 10-s transacupuncture (31–40 s), and a 30-s post acupuncture periods (41–70 s). Participants received acupuncture at the Heart point of the right ear. The needle was inserted to a depth of approximately 3 mm, with no additional stimulation; and remained inserted for 10 s. Derivatives and integrals of each pulse cycle during transacupuncture periods were solved. The peak slope values and area under the curve of the transacupuncture period were used to construct an interpolated curve. Results: Analysis of spline curves during the transacupuncture period showed a decrease in their values in the initial period of auriculopuncture stimulation, with a recovery in the second part. These results may indicate that auriculopuncture initially reduced cardiac output, possibly causing a secondary sympathetic response mediated by baroreceptors. Conclusion: These results may indicate that auriculopuncture initially reduced cardiac output, possibly causing a secondary sympathetic response mediated by baroreceptors.

Estimation of the High-Frequency Feature Slope in Gravitational Wave Signals from Core Collapse Supernovae Using Machine Learning

We conducted an in-depth exploration of the use of different machine learning (ML) for regression algorithms, including Linear, Ridge, LASSO, Bayesian Ridge, Decision Tree, and a variety of Deep Neural Network (DNN) architectures, to estimate the slope of the high-frequency feature (HFF), a prominent emergent feature found in the gravitational wave (GW) signals of core collapse supernovae (CCSN). We created a data set of CCSN GW signals generated by an analytical model that mimics the characteristics of the signals obtained from numerical simulations, particularly the HFF. This enabled us to simulate a wide range of HFF slope values and analyze their properties. We opted to employ ML for regression techniques, particularly a supervised learning approach, to analyze the data set due to the parameter chosen for estimating the slope of the HFF. This type of architecture is ideal for this purpose as it can detect the connections between input and output data. In addition, it is suitable for handling high-dimensional input data and produces efficient results with low computational cost. We evaluated the efficiency and performance of the ML algorithms using a set of metrics to measure their ability to accurately predict the HFF slope within the data set. The results showed that a DNN algorithm for regression exhibits the highest accuracy in estimating the slope of the HFF.

A new landslide detection approach using the combination of the normalized difference moisture index and slope classification analysis

ABSTRACT Landslides are the most common natural disasters that are often found in tropical and mountainous areas. This study aimed to identify the potency of the combination of the normalized difference moisture index (NDMI) and slope analysis in the Cameron Highlands region of Pahang State, Malaysia. Thus, four years (2014, 2017, 2020, and 2022) of time series analysis of Landsat 8 images were applied to generate NDMI, normalized difference vegetation index (NDVI), and land surface temperature (LST) for landslide detection. The extraction of NDMI and slope values was carried out in a GIS environment. Finally, the accuracy of the model was measured using the kappa statistic based on the ground truth data. The results revealed that landslides were detected in around 2,234 ha of the study area. Most of the landslides occurred in the northern and western parts, which corresponded with steep slopes (>55%) and low NDMI (<0.1). The LST had a notable impact on slope stability, where landslide areas tended to have a high temperature. There was an increase in LST of about 3°C in the study period. The change from forest areas to built-up areas was one of the contributors to the land temperature increasing in the Cameron Highlands area.

Impact of the Metal-Organic Frameworks Polymorphism on the Electrocatalytic Properties of CeO2 toward Oxygen Evolution.

Hydrogen (H2) is a viable alternative as a sustainable energy source, however, new highly efficient electrocatalysts for water splitting are still a research challenge. In this context, metal-organic frameworks (MOFs)-derived nanomaterials are prominent high-performance electrocatalysts for hydrogen production, especially in the oxygen evolution reaction (OER). Here, a new synthesis of two cerium oxide (CeO2) electrocatalysts using Ce-succinates MOFs as templates is proposed. The cerium succinates polymorphs ([Ce2(Succ)3(H2O)2], Succ = succinate ligand) were obtained via hydrothermal reaction and room temperature crystallization, adopting monoclinic (C/2c) and triclinic (P1̅) crystalline structures, respectively, confirmed by X-ray diffraction (XRD). MOFs-Ce were also characterized by infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM). CeO2 electrocatalysts were obtained via MOFs-Ce calcination at 350 °C in air, and characterized by XRD with Rietveld refinement, HRTEM, SEM, FT-IR, and Raman spectroscopy, UV-vis spectroscopy, X-ray photoelectron spectroscopy. Electrocatalytic performances were investigated in KOH 1.0 M solution, and overpotentials were η = 326 mV (for CeO2 (H) from monoclinic MOF-Ce) and η = 319 mV (for CeO2 (RT) from the triclinic MOF-Ce) for a current density of 10 mAcm-2. The Tafel slope values show the adsorption of intermediate oxygenated species as the rate-determining step. The high values of double-layer capacitance, the presence of oxygen vacancies, and low charge transfer resistance agree with the high performance in OER. Additionally, the materials were stable for up to 24 h, according to chronopotentiometry results.

Investigating Rainfall Patterns in South Singhbhum: A Non-parametric Approach Utilizing Mann-Kendall Tests and Sen's Slope Estimator

Aims: The South Singhbhum region is a physical region that experiences monsoon climate and frequent tropical cyclones and has global importance because of its abundant mineral resources like iron, manganese and its mining activities. The agricultural practices mainly depend on rainfall as it is a hilly area. For that reason, sustainable management is necessary to fulfill ecological, industrial, and community water requirements. So, the investigation carried out in this study focuses on the analysis of rainfall patterns within the South Singhbhum region by utilizing non-parametric statistical methodologies with the objective of identifying any discernible trends and variations that have occurred over time. Place and Duration of Study: South Singhbhum region of Odisha is extended between latitude to and longitude to . The area spread over on 45 blocks of Eight district in Odisha, India. The duration of time extended from 2008 to 2022. Methodology: The Mann-Kendall (MK) test is utilized to effectively detect the presence of monotonic trends within both the annual and seasonal rainfall datasets. Furthermore, the sequential Mann-Kendall (S-MK) test is employed to provide a comprehensive understanding of the temporal progression of these identified trends. The Sen's slope estimator is applied to accurately quantify the magnitude of the observed changes in rainfall patterns. Results: The annual study shows a steady declining trend from 2008 to 2021, with a Sen's Slope of 2.0376 and a Z value of 1.0949. However, March is the only month with a positive trend, as seen by its Sen's Slope of 3.0328 and Z value of 1.9708. There are significant variances in Sen's Slope values, which show disparities in the amount of changes, even if negative trends are common. The steepest negative slope is in July (-3.554), and the highest slope is in August (8.981). The S-MK Test was used to determine the start time of the South Singhbhum Region's annual rainfall time series, which revealed statistically declining patterns. It has been observed that the area's rainfall tendency varies frequently. In 2009, 2011, 2017, and 2019, the lines in the u(t) and u'(t) graphs intersect. The rainfall series experienced a reduction from 2008 to 2009, a rise from 2009 to 2011, a decrease from 2011 to 2017, another increase from 2017 to 2019, and a decline starting in 2019. Conclusion: The findings demonstrate that the South Singhbhum Region's rainfall patterns are trending negatively, which makes it clear that quick implementation of comprehensive water resource management methods is necessary to support sustainable development initiatives in the near future.

The value of a nomogram based on 18F-FDG PET/CT metabolic parameters and metabolic heterogeneity in predicting distant metastasis in gastric cancer.

To investigate the value of metabolic parameters and metabolic heterogeneity from pretreatment deoxy-2-[fluorine-18]-fluoro-D-glucose positron emission tomography/computed tomography (18F-FDG PET/CT) in predicting distant metastasis in gastric cancer. Eighty-six patients with pathologically confirmed gastric adenocarcinoma were included in this study. All patients underwent a whole-body 18F-FDG PET/CT scan before treatment. Clinicopathologic and imaging data were collected, including metabolic parameters such as maximum standardized uptake value (SUVmax), mean standardized uptake value (SUVmean), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) of the primary gastric cancer lesions. Heterogeneity index (HI)-1 was expressed as the absolute value of the linear regression slopes between the MTVs at different SUVmax thresholds (40%×SUVmax, 80%×SUVmax), while HI-2 was expressed as the difference between SUVmax and SUVmean. Patients were randomly divided into training and validation cohorts at a 7:3 ratio. The correlation between the above parameters and distant metastasis in gastric cancer was analyzed using the training cohort. A nomogram prediction model was then established and later verified with the validation cohort. Finally, decision curve analysis was used to evaluate the clinical utility of the model. This study included 86 patients with gastric cancer, with 60 (69.8%) in the training cohort and 26 (30.2%) in the validation cohort. There was no significant difference in the balanced comparison between both cohorts (all P>.05). Among all patients, 31 (36.0%) developed distant metastasis, while 55 (64.0%) did not. In patients who developed distant tumor metastasis, carcinoembryonic antigen, carbohydrate antigen (CA)12-5, CA19-9, CA72-4, MTV, TLG, and HI-1 were significantly higher than in patients without distant metastasis (all P<.05). Multivariate logistic regression analysis identified CA72-4 (OR: 1.151, 95% CI: 1.020-1.300, P=.023) and HI-1 (OR: 1.647, 95% CI: 1.063-2.553, P=.026) as independent risk factors for predicting distant metastasis in gastric cancer. The nomogram constructed from this analysis exhibited high predictive efficacy in the training (AUC: 0.874, 95% CI: 0.766-0.983) and validation (AUC: 0.915, 95% CI: 0.790-1.000) cohorts, providing a net clinical benefit for patients. HI-1 is an independent risk factor for predicting distant metastasis in gastric cancer. A comprehensive prediction model combining HI-1 with the tumor marker CA72-4 can increase the net clinical benefit for patients.

Optimizing tilt angle of PV modules for different locations using isotropic and anisotropic models to maximize power output

The optimal integration of Photovoltaic (PV) systems into an electric grid is dependent upon the total output power of the PV system. To optimize the output power of a PV system, the modules must be positioned at an optimal tilt angle (OTA) to maximize the absorption of solar radiations. This research focused on a mathematical model to optimize incident solar radiation. The proposed model is used to determine the OTA and evaluate its impact on the optimum configuration and power output capacity using MATLAB for six cities located in different temperature zones across Pakistan. The isotropic and anisotropic models have been used to calculate the total solar radiations (HT) on a sloped surface. During the summer season, all four selected models present similar findings in terms of the monthly average daily solar radiations on the tilted surface. During the winter season, the anisotropic models performed better than the isotropic models. The anisotropic model achieved a 14.82% energy increase in January and a 0.16% increase in June compared to the isotropic model. We present monthly and annual OTA calculated from the anisotropic model. The OTA has been determined for the HT across slope values ranging from 0° to 90° with a 1° resolution. The monthly OTA using anisotropic model for the Faisalabad, Lahore, Multan, RYK, Islamabad and Karachi ranges from 7° to 54°, 7° to 53°, 6° to 52°, 5° to 52°, 10° to 58° and 1° to 50° and the annual OTA for cities has been calculated to be 30.5°, 30.25°, 29.33°, 28.66°, 33.34° and 25.5° respectively. Utilizing the OTA calculated from the selected model, a PV array with a rated power of 52.200 kW has been used to analyze the system performance. The annual average output power at the monthly OTA results in gains of 8.83%, 9.40%, 9.78%, 9.77%, 9.82%, and 9.91% compared to the annual OTA. This research study is particularly beneficial for researchers and the industry in deploying PV systems across different climatic zones of Pakistan, intending to maximize output power while minimizing energy costs.

Construction of δ-FeOOH/NiMn2S4 heterointerface for efficient alkaline oxygen evolution reaction

Alkaline water electrolysis driven by sustainable energy is a viable approach for large-scale green hydrogen production. The development of non-precious metal-based electrocatalysts that combine high activity and stability for the alkaline oxygen evolution reaction (OER) is of great importance. In this work, we design and construct a δ-FeOOH/NiMn2S4/NF heterointerface using a solvothermal/calcination process followed by a facile successive ionic layer adsorption reaction (SILAR) treatment. Experimental tests indicate that the formation of the heterogeneous interface between the δ-FeOOH and the NiMn2S4 creates a good electron transport channel for an efficient electrocatalytic process and improves the charge transfer kinetics. As a result, the prepared δ-FeOOH/NiMn2S4/NF exhibits a low overpotential of 210 mV at 10 mA cm−2 and a low Tafel slope value of 46.6 mV dec−1, and satisfactory stability with a 92.9 % retention after 72 h of OER operation at around 100 mA cm−2. In situ Raman and in-situ attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR) tests show that the introduction of δ-FeOOH inhibits the oxidation of Ni2+ to Ni3+ and stabilizes the Ni-S bond to prevent its auto-oxidation, leads to an increase in the electrocatalytic OER activity.

DETERMINATION OF SOLAR REFLECTION COEFFICIENTS (ALBEDO) FROM SATELLITE IMAGES USING GOOGLE EARTH ENGINE PLATFORM

In many models calculating solar radiation, a combination of physical measurements and mathematical models is used to achieve results close to reality. In these calculations, the slope values and shading effects in the region being analyzed are often disregarded. Mathematical models such as ArcGIS's Area Solar Radiation (ASR) can calculate shading effects on three-dimensional surfaces. When solar radiation models are computed in three dimensions, accounting for solar rays reflected from the ground, in addition to atmospheric reflections, will increase accuracy. This study aimed to determine the surface reflectance coefficients that should be added in three-dimensional radiation models. In literature, general assumptions exist for surface reflectance coefficients, which represent very broad average values. However, this study aimed to establish precise albedo values for all land classes and surfaces. An area of approximately 1600 km² located in the mountainous region south of Karaman was chosen as the test area. This area was chosen in Karaman province because, as is known, this region has high solar energy potential. Sentinel 2A satellite images with a spatial resolution of 10 meters were used for both summer and winter seasons through the Google Earth Engine (GEE) platform. For the summer and winter applications, the albedo value for snowy surfaces was calculated as 0.86, while for light-colored buildings, it was 0.36 for summer and 0.28 for winter. Although examples were provided for some land classes, the study ultimately determined albedo values for all land surfaces without differentiation between classes.

Evaluation of Peripheral Circulatory Changes Following Hydrotherapy and Controlled Physical Training in Patients with Atherosclerotic Lower Limb Ischemia.

One hundred participants (both male and female) aged between 39 and 79 years old (60.0 ± 11.6) were included in the analysis, all diagnosed with peripheral circulation disorders. The participants were assigned to two groups. The study group received 10 whirlpool treatments of the lower limbs and a personalized training program. The control group only participated in the training sessions. Pre- and post-intervention evaluations included impedance plethysmography and the six-minute walk test (6MWT). Assessing the results of local flow parameters, after the procedures, a statistically significant increase in the pulse wave amplitude (PAmpl, p < 0.001) and systolic slope (PSlope, p < 0.001) values was found, as well as a statistically significant decrease in the crest time (CT, p < 0.001) and propagation time (PT, p = 0.007) values in the study group, which indicates an improvement in blood flow in the peripheral circulation. Also, in the 6 min walk test, a statistically significant increase in the walking distance was noted in the study group after the procedures. Physical training, combined with whirlpool massage treatment, has a beneficial effect on improving peripheral blood flow assessed by impedance plethysmography, as well as patients' tolerance to physical exercise. The inclusion of hydrotherapy as part of cardiovascular rehabilitation protocols in patients with peripheral ischemia is a promising form of conservative treatment.

Measuring Speech Intelligibility with Romanian Synthetic Unpredictable Sentences in Normal Hearing.

Understanding speech in background noise is a challenging task for listeners with normal hearing and even more so for individuals with hearing impairments. The primary objective of this study was to develop Romanian speech material in noise to assess speech perception in diverse auditory populations, including individuals with normal hearing and those with various types of hearing loss. The goal was to create a versatile tool that can be used in different configurations and expanded for future studies examining auditory performance across various populations and rehabilitation methods. This study outlines the development of Romanian speech material for speech-in-noise testing, initially presented to normal-hearing listeners to establish baseline data. The material consisted of unpredictable sentences, each with a fixed syntactic structure, generated using speech synthesis from all Romanian phonemes. A total of 50 words were selected and organized into 15 lists, each containing 10 sentences, with five words per sentence. Two evaluation methods were applied in two sessions to 20 normal-hearing volunteers. The first method was an adaptive speech-in-noise recognition test designed to assess the speech recognition threshold (SRT) by adjusting the signal-to-noise ratio (SNR) based on individual performance. The intelligibility of the lists was further assessed at the sentence level to evaluate the training effect. The second method was used to obtain normative data for the SRT, defined as the SNR at which a subject correctly recognizes 50% of the speech material, as well as for the slope, which refers to the steepness of the psychometric function derived from threshold recognition scores measured at three fixed SNRs (-10 dB, -7 dB, and -4 dB) during the measurement phase. The adaptive method showed that the training effect was established after two lists and remained consistent across both sessions. During the measurement phase, the fixed SNR method yielded a mean SRT50 of -7.38 dB with a slope of 11.39%. These results provide reliable and comparable data, supporting the validity of the material for both general population testing and future clinical applications. This study demonstrates that the newly developed Romanian speech material is effective for evaluating speech recognition abilities in noise. The training phase successfully mitigated initial unfamiliarity with the material, ensuring that the results reflect realistic auditory performance. The obtained SRT and slope values provide valuable normative data for future auditory assessments. Due to its flexible design, the material can be further developed and extended to accommodate various auditory rehabilitation methods and diverse populations in future studies.

Nationwide trends in sadness, suicidal ideation, and suicide attempts among multicultural and monocultural adolescents in South Korea during the COVID-19 pandemic, 2011-2022.

Researches on themental health of Korean adolescents during COVID-19 have largely focused on thosefrom monocultural families, but there is limited data on sadness, suicidal ideation, and suicide attempts in multicultural adolescents. This nationwide serial cross-sectional study included 688,708 adolescents aged 12-18years who participated in the Korean Youth Risk Behavior Web-based Survey from 2011 to 2022. We compared and analyzed the prevalence of sadness, suicidal ideation, and suicide attempts among multicultural and monocultural adolescents. Multicultural adolescents were defined as those with at least one non-Korean parent. In 2021, the prevalence of sadness among multicultural adolescents was 31.86% [95% confidence interval (CI) 30.00-33.71], suicidal ideation 17.17% (15.74-18.61), and suicide attempts 4.25% (3.51-4.99). Among monocultural adolescents, the prevalence rates were 26.09% (25.50-26.69) for sadness, 12.41% (11.97-12.85) for suicidal ideation, and 1.92% (1.76-2.67) for suicide attempts. Adolescents from multicultural backgrounds were found to have higher rates of sadness, suicidal ideation, and suicide attempts. In the general population, these rates haddecreased during the pre-pandemic period but increasedafter the onset of the pandemicthen stabilized from 2020 to 2021. Female gender, smoking, alcohol use, and low school performance emerged as significant risk factors. However, no distinct risk factors specifically linked to suicide attempts were identified. Joinpoint regression analysis results aligned with the beta slope values in the main findings, reflecting a consistent pattern across both analyses. This study revealed thatsadness, suicidal ideation, and suicide attempts increasedduring the pandemic, reversing a pre-pandemic decline. Multicultural adolescents faced these issues more than monocultural ones, underlining the need for targeted public health measures to support at-risk adolescents during pandemics.

Optimal Indocyanine Green Dosage for Repetitive Angiography for Laparoscopic Colorectal Surgery.

Background and Objectives: This study aimed to determine the minimal effective dose of indocyanine green (ICG) required for accurately assessing colonic perfusion during laparoscopic colorectal surgery using a laser-assisted laparoscopic near-infrared (NIR) camera system. Materials and Methods: In 15 patients with colorectal cancer undergoing right hemicolectomy, the left branch of the middle colic artery was preserved, and ICG angiography was performed in the transverse colon. To determine the optimal ICG dose, experimental doses of 0.01, 0.02, 0.03, 0.04, and 0.05 mg of ICG per patient's body weight (kg) were administered intravenously in each group. Additionally, a conventional dose of 0.2 mg/kg was administered in the same patients more than 30 min after the initial dose. For quantitative analysis, the fluorescent expression region was extracted, and fluorescence intensity was analyzed using automatic image processing. Analysis accessibility, T1/2MAX, perfusion time ratio, slope, artificial intelligence (AI)-based perfusion pattern analysis, and washout time were measured in 150 detailed regions of interest in each image. Results: Group 1 (0.01 mg/kg) showed significantly lower accessibility rates for quantitative analysis (48.0%) compared with Groups 2-5 (84.7-100%). The mean slope value in Group 1 was 3.7, which fell below the acceptable threshold (>4) and was significantly lower than that of the other groups (p < 0.001). An acceptable AI-based perfusion pattern was 14.2% in Group 1, significantly lower than in Groups 2-5 (66.4-100%). Washout time was significantly faster with minimal doses compared with conventional doses (39.0 ± 15.8 s vs. 117.5 ± 4.9 s, respectively, p < 0.001). Conclusions: This study supports the use of minimal ICG doses, ranging from 0.02 to 0.05 mg/kg, to optimize repetitive ICG angiography using a laser-assisted laparoscopic NIR camera.

MXene-supported 2D bimetallic chalcogenide electrocatalyst: Enhanced electrochemical seawater splitting

Hydrogen energy holds immense potential for revolutionizing modern energy technologies. Seawater electrolysis is a promising strategy for hydrogen production; however, the lack of effective electrodes limits its widespread application. Therefore, developing high-performance, cost-effective catalysts for water splitting is essential for sustainable energy conversion. In this context, we report a novel hybrid bimetallic selenide (CoMoSe2) and MXene (Ti3C2Tx) electrocatalyst, which exhibits remarkable catalytic performance for seawater electrolysis. The CoMoSe2@Ti3C2Tx electrocatalyst demonstrates outstanding catalytic capabilities, achieving overpotentials of 82 mV for hydrogen evolution reaction (HER) and 329 mV for oxygen evolution reaction (OER) at a current density of 10 mA cm⁻2 in alkaline conditions. The Tafel slope values are 124 mV dec⁻1 for hydrogen evolution and 69 mV dec⁻1 for oxygen evolution, outperforming their individual components. The enhanced bifunctional catalytic performance of the hybrid catalyst is attributed to the synergistic effect of Mo atoms within the CoSe2 crystal structure, which modifies the electronic structure and lowers the chemisorption energies of hydrogen and oxygen intermediates. The abundance of oxygen vacancies provides more reactive active sites and improves electrical conductivity. Additionally, the CoMoSe2@Ti3C2Tx composite has demonstrated remarkable bifunctional electrocatalytic performance for seawater splitting, achieving 10 mA cm⁻2 at overpotentials of 161 mV for HER and 354 mV for OER in alkaline seawater. The Volmer-Heyrovsky mechanism drives the remarkable long-term stability of the catalyst. This novel approach contributes to sustainable energy solutions by providing a fresh avenue for the development of effective catalysts to produce hydrogen from seawater.