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This study investigated the distributions of heavy metals (Cd, Cu, Hg, Ni, Pb, and Zn) in agricultural soils near coal-fired power plants in Taean and Seocheon, South Korea, considering wind direction and distance from the plants. Additionally, pollution assessment for these heavy metals was conducted using the geoaccumulation index (I geo ) and enrichment factor. Results showed that heavy metal concentrations in the studied soil samples were below Korean environmental criteria for agricultural soil (Cd: 4, Cu: 150, Hg: 4, Ni: 100, Pb: 200, and Zn: 300 mg/kg). However, a significant proportion of samples exceeded average levels found in uncontaminated soils. Spatial distribution analysis revealed higher concentrations of Cd and Pb southwest of the Taean plant, influenced by prevailing northeast winds. In Seocheon, soils within 4 km of the plant exhibited elevated levels of Cd and Ni, suggesting coal combustion as a potential contamination source. Pollution assessment indicated that Cd and Pb in soils near both thermal power plants were more enriched by artificial activity compared to agricultural soils in control areas. Sequential extraction results showed that heavy metals in soils within 4 km of the Seocheon plant had higher proportions of exchangeable to organic-associated forms than soils beyond 4 km, indicating a risk of high bioavailability near emission sources. This study highlights the significant impact of coal-fired power plant emissions on soil contamination, emphasizing the need for continuous monitoring and management. Environmental policies should consider wind patterns and proximity to emission sources to effectively mitigate contamination risks., Competing Interests: Declarations. Conflict of interests: The authors have no relevant financial or nonfinancial interests to disclose., (© 2024. The Author(s), under exclusive licence to Springer Nature B.V.)

High triplet (T1) energy exciplex hosts show great potential for accelerating high efficiency and a prolonged lifetime for stable blue phosphorescent organic light-emitting diodes (PhOLEDs). However, achieving high efficiency and device stability simultaneously in PhOLEDs is hard-fought due to the lack of a stable host with high triplet energy and better charge balance ability. To address this issue, herein, we developed two electron transport (ET) n-type host materials, namely 9-(4-(6-cyanodibenzo[b,d]furan-2-yl)pyridin-2-yl)-9H-carbazole-3-carbonitrile (CNCzPyDFCN) and 9-(2-(8-cyanodibenzo[b,d]furan-2-yl)pyridin-4-yl)-9H-carbazole-3-carbonitrile (CNDFPyCzCN). The molecules were designed via quantum chemical/molecular dynamics (QC/MD) simulation methods. As a result, both ET n-type hosts achieved a high T1 of >2.96 eV and appropriate HOMO/LUMO energy level for outstanding electron-transporting properties. Furthermore, it was clarified that an exciplex was formed between our n-type hosts and p-type host 2,2′-di(9H-carbazol-9-yl)-1,1′-biphenyl (oCBP). Consequently, PhOLEDs were fabricated by introducing both exciplex systems and a blue phosphorescent emitter (CN–Ir). In particular, the device using oCBP:CNCzPyDFCN shows a high external quantum efficiency (EQE) of over 29% and a device lifetime of LT50 33.9 h at an initial luminescence of 1000 cd m−2 with a low turn-on voltage. Thus, exciplex study with a high T1 host is a promising technology for long-term stable blue PhOLEDs. [ABSTRACT FROM AUTHOR]

This study analyses the impact of process parameters on Glass Fiber Reinforced Polymer (GFRP) components produced through conventional drilling on a CNC drilling machine (VMC). GFRP's challenging machinability is due to its high strength-to-weight ratio, durability, and customizable mechanical properties. The study aims to minimize kerf angles in drilled holes, identifying optimal parameter combinations based on Signal-to-Noise ratios. The best combination of parameters that used to reduce the value of the kerf angle was considered at 2,800 RPM spindle speed and 1,200 mm/rev feed rate. The experimental work reveals that the spindle speed significantly affects the kerf angle, while the feed rate and spindle speed both influence the variation in the kerf angle and show the best results at the ideal values of the two parameters. The study details an analysis of the process parameters of drilled holes on kerf angle in multiple holes in the specimen, applying Taguchi's design of experiments and analysis of variance. Comparison of findings was made with existing literature on determination of the importance of spindle speed and feed rate for the determination of kerf angle. The best results were obtained when all these parameters set to the ideal values, where the minimum angular kerf of 0.1145° was observed. [ABSTRACT FROM AUTHOR]

Racialized Sexual Discrimination (RSD), also referred to as "sexual racism," is widely reported among young sexual minority Black men (YSMBM). Though RSD is driven in part by sexual scripts and racial stereotypes, little is known about YSMBM's experiences with RSD with respect to their sexual positioning roles. Using data from a cross-sectional web-survey of YSMBM (N = 726), a multivariate Kruskal Wallis test was conducted comparing YSMBM who identified as mostly bottom, versatile, or mostly top, on the degree to which they were affected by four RSD experiences, as well as the frequency with which they encountered these experiences. Men identifying as mostly bottom reported significantly stronger negative reactions to same-race rejection and encountering sexual role assumptions than men identifying as mostly top. Men identifying as versatile encountered same-race rejection significantly more frequently than men identifying as mostly top. Men identifying as mostly bottom encountered White superiority significantly more frequently than men identifying as mostly top. RSD may impact YSMBM differentially based on sexual position. These findings may have implications for culturally competent clinical practice, as well as analytic implications (e.g., estimating more complex statistical models) for sexual racism research, which remains an important yet underexamined field in the health sciences. [ABSTRACT FROM AUTHOR]

Currently, exciplex-type thermally activated delayed fluorescence (TADF) materials are emerging as a promising strategy for optimizing organic light-emitting devices (OLEDs). However, achieving highly efficient multi-color OLEDs based on exciplexes remains a formidable challenge. Herein, a deep-blue fluorescent emitter, named BOBTFB, endowed with a benzene (B), 5,9-dioxa-13b-boranaphtho[3,2,1-de]anthracen (BO) and trifluoromethylbenzene (TFB) as the bridged core, electron-acceptor moiety, and π-spacer, respectively, was designed and synthesized. Employing BOBTFB as an identical exciplex acceptor and pairing it with distinct electron donors (TCTA, TAPC and m-MTDATA), blue, green and yellow exciplex-based solution-processed OLEDs have been obtained for the first time with emission peaks located at 470 nm, 510 and 564 nm, respectively. Notably, the yellow device exhibited an exceptionally low turn-on voltage (Von) of 2.2 V, a maximum current efficiency (CEmax) of 38.83 cd A−1, and a maximum external quantum efficiency (EQEmax) of 12.18%, respectively, which results from the low non-radiative transition rate and fast radiative transition rate of the BOBTFB:m-MTDATA forming exciplex. Moreover, the combination of TCTA:m-MTDAT:BOBTFB results in an exciplex white OLED with an EQEmax of 1.49%, a maximum color rendering index (CRI) of 82 and CIE coordinates of (0.23, 0.33), respectively. As far as we know, this work is the first reported utilization of an identical electron acceptor for solution-processed multi-color OLEDs. [ABSTRACT FROM AUTHOR]

The transcriptional cascade and regulatory loop play crucial roles in regulating plant-specialized metabolite biosynthesis. Capsaicinoids are unique to the genus Capsicum and confer a pungent flavor to its fruits. However, the transcriptional regulation of capsaicinoid biosynthesis remains largely unknown. In this study, two AP2/ERF transcription factors (TFs), CaERF102 and CaERF111, were characterized for their role in the capsaicinoid biosynthesis process. Expression analysis of two ERFs and capsaicinoid biosynthetic genes (CBGs) suggested that they were associated with capsaicinoid biosynthesis. Both ERFs encode nuclear-localized proteins and function as transcriptional activators through their C-terminal activation motifs. The two ERF TFs participated in capsaicinoid biosynthesis by directly activating the promoters of key CBGs, and this activation was significantly enhanced when CaMYC2 was co-expressed. Moreover, CaERF102 and CaERF111 were found to interact with CaMYC2. This study helps elucidate the AP2/ERF TF regulatory network that governs capsaicinoid biosynthesis in Capsicum species. [ABSTRACT FROM AUTHOR]

Variations in the microstructural morphology with building direction during selective laser melting (SLM) result in the anisotropic mechanical properties of the specimens, while heat treatment effectively reduces this anisotropy. The degree of anisotropy of the material can be assessed by calculating the variance (σ) of the mechanical properties (strength, hardness) at different building directions at different temperatures. In this work, the effects of heat treatment temperatures (450°, 750 °C, and 1050 °C) and building directions (0°, 45°, 60°, and 90°) on the microstructure, hardness, and tensile properties of selective laser melting (SLM) SS316L were investigated. Unheated SLM SS316L specimens exhibit significant anisotropy (σUTS = 16.67, σUE = 9.60, and σHV = 9.60), while heat treatment effectively reduces this anisotropy. As the heat treatment temperature increases, the melt pool boundaries disappear and grains become uniform at 750 °C, significantly reducing the anisotropy of the mechanical properties (σUTS = 14.65, σUE = 4.33, σHV = 6.72). At 1050 °C, the grain size increases slightly, resulting in a minor rise in anisotropy (σUTS = 14.93, σUE = 4.97, σHV = 8.39) compared to that seen at 750 °C. After heat treatment, the SLM SS316L specimen heated at 450 °C shows the lowest anisotropy. Notably, the specimens built in the 0° direction and heated at 450 °C exhibit finer sub-grains and enhanced mechanical properties, achieving a hardness of 244.43 HV, a tensile strength of 655.85 MPa, and an elongation of 21.25%. [ABSTRACT FROM AUTHOR]

Biogenic amines (BAs), produced in fish and seafood due to microbial contamination, pose significant health risks. This study introduces a novel ratiometric fluorescent probe, synthesized by integrating rhodamine 6G(R6G) and gold nanoparticles (AuNCs), for the sensitive and specific detection of BAs. The probe operates on the principle of BAs hydrolysis, catalyzed by diamine oxidase, to produce hydrogen peroxide (H2O2), which selectively quenches the fluorescence of AuNCs at 620 nm, while the fluorescence of R6Gat 533 nm remains unaffected. The ratio of I620/I553 demonstrated excellent linearity with a wide dynamic range (1–1000 μM) and a low detection limit of 0.1 μM. Validation using grass carp samples showed high recovery rates (97.57% to 104.29%), confirming the probe's efficacy and potential for practical application in food safety monitoring. [ABSTRACT FROM AUTHOR]

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We develop a new scattering-based framework for the holographic encryption of analog and digital signals. The proposed methodology, termed 'differential sensing', involves encryption of a wavefield image by means of two hard-to-guess, complex and random scattering media, namely, a background and a total (background plus scatterer) medium. Unlike prior developments in this area, not one but two scattering media are adopted for scrambling of the probing wavefields (as encoded, e.g. in a suitable ciphertext hologram) and, consequently, this method offers enhanced security. In addition, while prior works have addressed methods based on physical imaging in the encryption phase followed by computational imaging in the decryption stage, we examine the complementary modality wherein encryption is done computationally while decryption is done analogically, i.e. via the materialization of the required physical imaging system comprising the ciphertext hologram and the two unique (background and total) media. The practical feasibility of the proposed differential sensing approach is examined with the help of computer simulations incorporating multiple scattering. The advantages of this method relative to the conventional single-medium approach are discussed for both analog and digital signals. The paper also develops algorithms for the required in situ holography as well as a new wavefield-nulling-based approach for scattering-based encryption with envisioned applications in real-time customer validation and secure communication. [ABSTRACT FROM AUTHOR]

The operation of large reservoirs significantly modifies flow–sediment regimes, and the reaches immediately downstream of the dams are the first to undergo responsive channel adjustments. Considering that the geomorphological responses are directly related to the flood control safety, channel stability and other sustainable functions of rivers, this paper explores the similarities and dissimilarities of the channel adjustments in the two reaches with gravel–sand beds immediately downstream of the Xiangjiaba reservoir and the Three Gorges Dam, respectively. The results show that major erosion primarily occurred during the initial years of reservoir impoundment. And then with the prominent reduction in washable sediment on the riverbed, the erosion intensity further weakened. It takes 6 to 13 years for the two reaches to reach a new state of relative equilibrium. In comparison, after the equilibrium state has been achieved, the reach with significant tributary sediment inflows exhibits alternating erosion and deposition dynamics, while the other remains relatively stable. The tributaries that transport a large amount of sediment during floods are the main sources of sediment deposition in the downstream reaches of the Xiangjiaba reservoir. However, the tributary inflow of the Qing River with low sediment concentrations has little impact on the riverbed evolution of the reaches from Yichang to Zhicheng immediately downstream of the Three Gorges Dam. These findings contribute to a deeper understanding of geomorphic adjustments near dams in response to upstream damming. [ABSTRACT FROM AUTHOR]

Multi-resonance thermally activated delayed fluorescence (MR-TADF) emitters have broad applications in organic light-emitting diodes (OLEDs). However, their device performance is often limited by the large conjugated planarity that makes them easily aggregate in the form of π–π stacking, resulting in aggregation-caused quenching (ACQ) and the formation of excimers, which reduce exciton utilization efficiency and color purity. To address these issues, large shielding units can be incorporated to prevent interchromophore interactions. In this study, we introduced 10,10-diphenyl-5,10-dihydro-dibenzo[b,e][1,4]azasiline (DPPASi), which contains a silicon atom, at the para-carbon position of a B-substituted phenyl ring as a steric group to synthesize the emitter BNSi. This modification successfully achieved a narrow-band blue emission at high doping ratios with a maximum external quantum efficiency (EQEmax) of 34.8% in the corresponding OLED device. Even at luminance levels of 1000 cd m−2, an impressive EQE of nearly 20% was maintained. This study provides valuable insights for designing efficient narrow band blue emitters by utilizing the steric effect. [ABSTRACT FROM AUTHOR]

High-accuracy gully erosion susceptibility maps play a crucial role in erosion vulnerability assessment and risk management. The principal purpose of the present research is to evaluate the predictive power of individual machine learning models such as random forest (RF), decision tree (DT), and support vector machine (SVM), and ensemble machine learning approaches such as stacking, voting, bagging, and boosting with k-fold cross validation resampling techniques for modeling gully erosion susceptibility in the Oued El Abid watershed in the Moroccan High Atlas. A dataset comprising 200 gully points, identified through field observations and high-resolution Google Earth imagery, was used, alongside 21 gully erosion conditioning factors selected based on their importance, information gain, and multi-collinearity analysis. The exploratory results indicate that all derived gully erosion susceptibility maps had a good accuracy for both individual and ensemble models. Based on the receiver operating characteristic (ROC), the RF and the SVM models had better predictive performances, with AUC = 0.82, than the DT model. However, ensemble models significantly outperformed individual models. Among the ensembles, the RF-DT-SVM stacking model achieved the highest predictive accuracy, with an AUC value of 0.86, highlighting its robustness and superior predictive capability. The prioritization results also confirmed the RF-DT-SVM ensemble model as the best. These findings highlight the superiority of ensemble learning models over individual ones and underscore their potential for application in similar geo-environmental contexts. [ABSTRACT FROM AUTHOR]

While geobotanists have long used plant occurrence to locate subsurface resources, none have utilised floristic surveys as evidence in models of mineral potential. Here, we combine plant species distributions with terrain metrics to produce predictive models showing the probability of bauxite presence. We identified nineteen taxa with statistically significant associations with known bauxite deposits and identified eleven terrain metrics from previous studies. We grouped variables into three variable sets (floristic, topographic, and topo-flora) and produced mineral potential models for each using four algorithms or approaches: (a) a generalised linear model (GLM); (b) random forest (RF); (c) maxent (ME); and (d) a heterogenous stacking ensemble (GLM-RF-ME). Overall, the random forest model outperformed all algorithms including the ensemble based on the area under the curve (AUC) metric. The floristic set of variables outperformed the topographic set (AUC: 0.86 v 0.82). However, together they had the greatest predictive capacity (AUC: 0.89). Six taxa, including Banksia grandis, Leucopogon verticillatus, and Persoonia longifolia, were indicators of bauxite presence, while five other taxa, including Xanthorrhoea preissii and Hypocalymma angustifolium, were associated with bauxite absence. Important topographic variables were topographic wetness, landscape position, and valley depth, which characterised bauxite locations as being well drained, in the upper slope positions of subdued hills, and at some distance from valleys. The addition of floristic surveys provides a new line of evidence about the overlying botanical life that tolerates, accumulates, or avoids bauxite or associated minerals. As opposed to drilling, both datasets can be collected and interrogated at low cost and without impact to the surrounding environment. These data are valuable additions to future applications of mineral potential modelling. [ABSTRACT FROM AUTHOR]

This paper reviews the field of cascaded metasurfaces, which are advanced optical devices formed by stacking or serially arranging multiple metasurface layers. These structures leverage near-field and far-field electromagnetic (EM) coupling mechanisms to enhance functionalities beyond single-layer metasurfaces. This review comprehensively discusses the physical principles, design methodologies, and applications of cascaded metasurfaces, focusing on both static and dynamic configurations. Near-field-coupled structures create new resonant modes through strong EM interactions, allowing for efficient control of light properties like phase, polarization, and wave propagation. Far-field coupling, achieved through greater interlayer spacing, enables traditional optical methods for design, expanding applications to aberration correction, spectrometers, and retroreflectors. Dynamic configurations include tunable devices that adjust their optical characteristics through mechanical motion, making them valuable for applications in beam steering, varifocal lenses, and holography. This paper concludes with insights into the potential of cascaded metasurfaces to create multifunctional, compact optical systems, setting the stage for future innovations in miniaturized and integrated optical devices. [ABSTRACT FROM AUTHOR]

The evaluation and diagnosis of altered mental status in the pregnant or postpartum patient largely parallels the approach used for any other patient; however, there are several critical differences including that some neuroobstetric diagnoses require emergent delivery of the fetus. Being familiar with the physiological changes and medical complications of pregnancy and delivery is therefore essential. This review first addresses pregnancy-specific disorders that may result in altered mental status, such as the hypertensive disorders of pregnancy and pregnancy-related metabolic and endocrinopathies. The focus then shifts to the complex physiologic changes in pregnancy and how these changes contribute to the distinct epidemiology of pregnancy-related cerebrovascular complications like intracranial hemorrhage, ischemic stroke, and reversible cerebral vasoconstriction syndrome. Medical disorders that are not unique to pregnancy, such as infections and autoimmune conditions, may present de novo or worsen during pregnancy and the peripartum period and require a thoughtful approach to diagnosis and management. Finally, the unique nervous system complications of obstetric anesthesia are explored. In each section, there is a focus not only on diagnosis and syndrome recognition but also on the emergent treatment needed to reverse these complications, bearing in mind the unique physiology of the pregnant patient. [ABSTRACT FROM AUTHOR]

High-temperature (15-37°C) aging can shorten the tenderizing time of beef; however, the use of constant temperature heating can lead to microbial spoilage. This study tested radiofrequency (RF) tenderization (RF-T) to find the appropriate conditions for the aging-like effect of beef without microbial spoilage. After subjecting beef to 22 h RF-T with four different cooling temperatures (15, 5, -10, and -20°C), the proliferated aerobic bacteria on the surface showed a concentration of 6-6.2 log CFU/g at -10 and -20°C, lower than 7-7.5 log CFU/g at 15 and 5°C. When beef was treated with 25 W/kg RF heating power for 48 h RF-T, the estimated reduction rate of the sliced shear force (SSF) and the increase rate of glutamic acid based on the weight before RF-T were 22.6% and 1.51-fold, which were greater than 19.6% and 1.37-fold with 20 W/kg, and 11.0% and 1.11-fold with 15 W/kg. The optimal specific RF heating power was calculated as 30 W/kg from the results' extrapolation. When processed for 48 h under optimal conditions (30 W/kg specific RF heating power, -20°C cooling air), the tenderization rate and the increased rates of free amino acids based on the weight before RF-T of beef reached over 20% and 1.5-fold with 5.22 log CFU/g aerobic bacteria, which was lesser than the Korean regulation value of 6.7 log CFU/g (5 × 10 6  CFU/g). Therefore, RF-T could be proposed as a promising high-temperature tenderization method with lowered risk of microbial spoilage. PRACTICAL APPLICATION: We showed that lowering the chamber temperature during RF-T was effective in surface drying and inhibiting aerobic bacteria. RF-T for 24-48 h with 30 W/kg specific RF heating power had an aging-like effect given tenderization and increase in FAAs. Moreover, by providing the matching circuit and impedance during RF-T, this method could be industrially reproducible., (© 2023 Institute of Food Technologists.)

This review outlines problems and progress in development of solution-processed organic light-emitting diodes (SOLEDs) in industry and academia. Solution processing has several advantages such as low consumption of materials, low-cost processing, and large-area manufacturing. However, use of a solution process entails complications, such as the need for solvent resistivity and solution-processable materials, and yields SOLEDs that have limited luminous efficiency, severe roll-off characteristics, and short lifetime compared to OLEDs fabricated using thermal evaporation. These demerits impede production of practical SOLED displays. This review outlines the industrial demands for commercial SOLEDs and the current status of SOLED development in industries and academia, and presents research guidelines for the development of SOLEDs that have high efficiency, long lifetime, and good processability to achieve commercialization., (© 2023 Wiley-VCH GmbH.)

Bioscaffolds with characteristics of the tumor microenvironment is an important substrate to support the formation of multicellular tumor spheroids (MCTS). Conventional biomaterials promote MCTS formation using tumor extracellular matrix (ECM) components and exogenous growth factors, but lack individualized tumor cell niche construction which may restricts cell biology and drug discovery research. Herein, an ECM mimicked fiber composite dual-network hydrogel (FCDNG) was constructed. The 3D nanofibrous framework was introduced into the hydrogel by a "dispersion-swelling" method and an alginate/platelet-rich plasma (PRP) dual-network hydrogel was constructed by a simple "one-step" activation process. The scaffold can well control the physicochemical conditions that mimic the ECM structure and biomimetic mechanical properties. The fibrin formed by PRP can promote tumor cell proliferation, angiogenesis and cancer stem cell enrichment. Meanwhile, FCDNG has suitable degradation properties to meet the matrix remodeling requirements during the formation of MCTS. Tumor cells cultured in FCDNG had enhanced tumor stemness, proliferation, and resistance to chemotherapeutic agents, and thus providing an effective strategy for clinical drug evaluation. [ABSTRACT FROM AUTHOR]

Two lignin model compounds, eugenol (Eu) or 2-methoxy-4-propylphenol (MPP), were esterified with a protonating acetic acid (AcA), H2SO4 catalyst and water. Initial product analysis showed a high related number of the unspecific process species of Eu reactions. Therefore, research was continued only with MPP. Temperature, equivalent MPP/AA molar ratio and quantified H2SO4 mass amount were varied, reactants were monitored, and it was determined that the functionalisation's best conditions were 130 °C, indicated total contained MPP/AA 1:3 and 1 mol% rate-increasing H2SO4. Yields exceed 15 mol%. Other H+ donors, HCl or p-toluene-sulfonic acid, were used, but resulted in lower yields (2 mol% or less). Afterwards, MPP esterification was attempted with five bio-based molecules, but only levulinic acid produced a measurable ester value (4 mol%). Two enzymes, lipase from Rhyzopus oryzae or immobilized lipase B from Candida antarctica, were also applied, not forming products. A micro-kinetic system representation was developed, based on a proposed elementary mechanism, which revealed the comparable activation energy of MPP substitution, catalysed by H2SO4. Barrier (24 kJ mol–1) was less than that with H-beta (zeolite) (39 kJ mol–1), while higher than that with AmberLite XAD 16 (resin) (10 kJ mol–1). [ABSTRACT FROM AUTHOR]