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Developing metal‐free carbon catalysts is critical to achieve the electrosynthesis of hydrogen peroxide (H2O2) via two‐electron oxygen reduction reaction (2e− ORR) using seawater as electrolyte. Herein, N‐rich doped carbon (NC) is synthesized by directly pyrolyzing guanine as both N and C sources, which can facilitate the formation of ultrahigh‐N dopant (up to 33.89 at.%), and their ratios. The NC obtained at 700 °C with hydrogenated pyridine‐N and pyrrole‐N (3:2) dopants exhibits a superior selectivity of H2O2 (up to 96%), high mass activity of 545.5 A g−1 at 0.2 V versus RHE and stable production of H2O2 with 16.8 molgcat−1h−1${\rm{mol}}\;{\rm{g}}_{{\rm{cat}}}^{ - 1}{{{\rm{h}}}^{ - 1}}$ in 0.5 M NaCl. In situ Fourier transform infrared spectrum analysis proves that hydrogenated pyridine‐N and pyrrole‐N dopants play a critical role in constructing metal‐free active sites for the synthesis of H2O2. Meanwhile, theoretical calculations further reveal that compared to non‐hydrogenated N dopants, hydrogenated pyridine and pyrrole N can tune the projected density of states of 2pz orbitals of their adjacent carbon atoms approaching Fermi Level, enhancing *OOH to H2O2 through 2e− ORR rather than H2O via 4e− ORR. This work provides new insights for developing metal‐free catalysts for efficient electrosynthesis of H2O2 using seawater resources as promising electrolytes. [ABSTRACT FROM AUTHOR]

ABSTRACT Bi‐based organic halides have attracted widespread attention as potential substitutes for lead‐based organic halide perovskites and have been explored and applied in many optoelectronic devices. The rational design of organic Bi‐based halides is a popular research topic. In this work, we used benzylammonium (BA) cations to synthesize BA3Bi2I9 (BBI) perovskite material and FA3Bi2I9 (FBI, FA [formamidinium]) as control. We observe that the benzene rings in BA cations overlap with each other due to the benzene rings Π‐Π conjugation in the crystal structure of BBI, which exhibits large interplanar spacing due to large BA ions. BBI has preferential orientation along the (020) crystal plane. Due to conjugation, scanning electron microscopy (SEM) and energy dispersive spectrometer (EDS) mapping images indicate that the surface of the BBI thin film is smoother and more uniform than that of the FBI thin film. We fabricated the device by growing thin films of BBI and FBI on ITO interdigital electrodes. The photodetector based on BBI SC exhibits stability and regularity with turning on/off of the light at different intensities (10, 20, 30, and 40 W m−2) and wavelengths (386, 397, 405, and 433 nm). The ultraviolet–visible (UV–vis) absorption and reflection spectrum analysis shows that BBI has a slightly wider bandgap than FBI. This study can provide some ideas for the design Π‐Π conjugation in organic metal halides. [ABSTRACT FROM AUTHOR]

Bimetallic single‐atom‐dimer (SAD) with unique electronic structures and adsorption properties presents exceptional catalytic performance owing to atomic‐level synergistic effects from direct bonding between different metal atoms. However, inherent characteristics of substrate present great challenges in their synthesis and mechanism investigation. Herein, a unique phosphorus modified atomic layer deposition (P‐ALD) strategy is designed to synthesize P‐anchored Pt–W dimers, overcoming substrate limitation (Pt1W1–P/C). Motivated introduction of atomic P site via ALD can effectively anchor one‐to‐one AB bimetallic dimer structure on various substrates, confirmed by X‐ray absorption spectroscopy (XAS). Density functional theory reveals an interatomic synergistic adsorption mechanism, with W as primary hydrogen adsorption site extending to Pt, optimizing hydrogen coverage, leading to 60‐fold increase in mass activity compared to commercial Pt/C in both acidic and alkaline electrolytes. Anion exchange membrane water electrolyzer with ultra‐low loading Pt1W1–P/C (50 µgPt cm−2) catalyst operates durability at 1000 mA cm−2 for 550 h with ultra‐low degradation of 38 µV h−1. Operando XAS confirms hydrogen adsorption pathway between atoms and remarkable self‐healing ability of P–Pt–W–O sites under all‐pH conditions. These findings extend the application domain of SAD to catalytic manufacturing methods and aid in designing advanced materials with multi‐atomic active sites. [ABSTRACT FROM AUTHOR]

Aim: To investigate the effects of high‐intensity interval training (HIIT) on periodontitis (PD) progression and behavioural outcomes. Materials and Methods: Forty‐eight Wistar rats were divided into four groups: non‐trained (NT); non‐trained with PD; HIIT with PD; and HIIT. The HIIT protocol, involving daily treadmill sessions, spanned 8 weeks, with PD induced by ligature after the 6th week. Behavioural tests were conducted to assess anxiety and memory. Post euthanasia, we evaluated the systemic inflammatory profile and oxidative stress markers in the hippocampus and amygdala. A morphological evaluation and elemental composition analysis of the mandibular alveolar bone were performed. Results: PD exacerbated alveolar bone level, bone surface damage and alterations in calcium and phosphorus percentages on the bone surface (p <.05), while HIIT attenuated these changes (p <.05). HIIT improved systemic inflammatory markers altered by PD (tumour necrosis factor [TNF]‐α, interleukin [IL]‐10, TNF‐α/IL‐10 and IL‐1β/IL‐10 ratios, p <.05). PD animals exhibited lower total antioxidant capacity and levels of thiobarbituric acid reactive substances in the amygdala and hippocampus, respectively (p <.05). HIIT maintained these parameters at levels similar to those in NT animals. HIIT improved anxiety and memory outcomes altered by PD (p <.05). Conclusions: HIIT attenuates systemic inflammation, anxiety and memory outcomes promoted by PD. [ABSTRACT FROM AUTHOR]

ABSTRACT Silicon nanopowders with nitrogen heterocyclic carbene (NHC) and butyl as stabilizing ligands were synthesized by bottom‐up chemical methods. Transmission electron microscopy (TEM) was used to obtain nanoparticle size distribution with 1.8–2.5‐nm average diameter. Optical characteristics (photoluminescence [PL] and infrared [IR] absorption spectra) of samples were investigated as fabricated and on different steps of irradiation by high‐energy 22.5‐MeV protons. The PL spectral changes are slightly different for two cases, but in general, we can see a decrease in luminescence amplitude with fluence growth up to 4·1014 cm−2, mainly for NHC‐stabilized nanosilicon. Main mechanisms of radiation‐induced changes in nanosilicon sample optical properties are discussed by the joint use of PL and IR spectra analysis. [ABSTRACT FROM AUTHOR]

A multi‐object silicon photonic spectrometer with N input ports is proposed and realized by integrating a multi‐channel passband optical filter (POF), a tunable narrow‐band optical filter as well as a calibration‐free N × 1 Mach–Zehnder switch (MZS) array. Here, the multi‐channel POF consisting of a multimode waveguide grating (MWG) and a mode (de)multiplexer is used to achieve a broadened working window and an enhanced dynamic range for the present spectrometer, while the narrow‐band optical filter is realized with a thermally‐tunable Euler micro‐ring resonator (EMR) for achieving a very high spectral resolution. The introduction of the N × 1 MZS enables the time‐division‐multiplexed (TDM) spectrum analysis for multiple objects. In this paper, a multi‐object silicon photonic spectrometer with 16 input ports is demonstrated with an on‐chip loss of less than 3 dB and inter‐channel crosstalk as low as −25 dB. This multi‐object spectrometer can be used to analyze the spectra of 16 objects one by one by setting the 16 × 1 MZS, the resolution is as high as 50 pm, and the working window is ≈84 nm. [ABSTRACT FROM AUTHOR]

Multistimuli‐responsive color‐changing materials have potential applications in areas such as chemical sensing and anti‐counterfeiting. In this work, a fluoro‐phenyl‐acetyl‐substituted viologen derivative (FPAV·Cl2) is synthesized, which can form a supramolecular inclusion complex with cucurbit[7]uril (Q[7]) via self‐assembly. Significantly, the resulting inclusion complex FPAV2+@Q[7] in the solid‐state exhibits visual color changes in response to multiple external stimuli including light, heat, and vapors of ammonia and organic amines. The electron spin resonance (ESR) and ultraviolet–visible (UV–vis) spectra analysis reveals that the photochromic, thermochromic, and vapochromic behavior of FPAV2+@Q[7] is due to the generation of FPAV+• free radicals resulting from electron transfer. Furthermore, in the solid‐state, FPAV2+@Q[7] shows controllable fluorescence regulated by its chromic process. Based on the multi stimuli‐responsive color‐changes and fluorescence properties of FPAV2+@Q[7], its practical applications in erasable inkless printing, multiple anti‐counterfeiting processes, visible ammonia/organic amines detection, and information encryption are demonstrated. The supramolecular strategy of encapsulating viologen derivatives into macrocycles provides a general method for fabricating multi stimuli‐responsive chromic materials with multiple practical applications. [ABSTRACT FROM AUTHOR]

Mn2(C2H6N6)4(NO3)4·2H2O (Mn) as one of the energetic coordination complexes was chosen for high‐pressure research. In this work, Mn was analyzed by in situ Raman scattering, infrared absorption, and synchrotron angle‐dispersive X‐ray diffraction (ADXRD) technologies up to ~20 GPa at room temperature. The vibrational modes of Mn at ambient pressure were comprehensively resolved based on the experimental results. Detailed spectral analyses revealed that Mn underwent three pressure‐induced phase transitions at 0.5, 2.5, and 5.7 GPa, respectively. ADXRD experiments confirmed the existence of these three phase transitions in Raman and infrared spectra analyses. Based on the analysis of the vibrational spectra and the changes of lattice parameters under pressure, it can be considered that the deformation of the 3‐hydrazino‐4‐amino‐1, 2, 4‐triazole (HATr) ligand led to the first phase transition, and the distortion of the triazole ring induced the second phase transition, and the rearrangement of the hydrogen bonds resulted in the third phase transition. In addition, it can be inferred from Raman spectra and ADXRD data that Mn may have experienced the abnormal expansion during the first phase transition. This work may lay the foundation for further investigating the structure and properties of energetic coordination complexes under pressure. [ABSTRACT FROM AUTHOR]

In this work, 2,2‐bis(3‐amino‐4‐hydroxyphenyl) hexafluoropropane (APAF) was used as the fixed diamine monomer, and 4,4′‐(hexafluoroisopropylidene) diphthalic anhydride (6FDA), 4,4′‐oxydiphthalic anhydride (ODPA), 3,3′,4,4′‐biphenyltetracarboxylic diandhydride (BPDA) and pyromellitic dianhydride (PMDA) were selected as four different dianhydride monomers, respectively, to prepare the thermally rearranged polybenzoxazole (TR‐PBO) gas separation membranes with different structures via a thermal rearrangement reaction at 450°C. The microstructure of TR‐PBO membranes was investigated using X‐ray diffraction and positron annihilation spectroscopy. All the TR‐PBO membranes exhibit bimodal free volume structure, containing ultramicropores (<0.7 nm) and micropores (<2 nm) with size of 3.6–4.6 and 7.6–8.4 Å, respectively. As the steric hindrance of the bridging groups in the dianhydride monomers increases, the radius and number of pores in the membranes increases, leading to an increase in fractional free volume (FFV). The pure gas permeation test shows a positive correlation between gas permeability and FFV in the TR‐PBO membranes, indicating that an increase in FFV is favorable for the diffusion of gas molecules. Particularly, the ultramicropores play a decisive role on the gas selectivity. All the TR‐PBO membranes exhibit excellent gas permeaselectivity. Among them, the H2/CH4 separation performance of APAF‐6FDA and APAF‐ODPA membranes approaches the 2008 Robeson upper bound, which is due to the high number of both micropores and ultramicropores. Our results demonstrate that the free volume structure of polymer membranes can be designed by selecting monomers with different structures and utilizing thermal rearrangement reactions, allowing for the preparation of gas separation membranes with high permeability and selectivity. [ABSTRACT FROM AUTHOR]

Objective: Deep brain stimulation (DBS) is a promising approach for the treatment of epilepsy. However, the optimal target for DBS and underlying mechanisms are still not clear. Here, we compared the therapeutic effects of DBS on distinct septal subregions, aimed to find the precise targets of septal DBS and related mechanisms for the clinical treatment. Methods: Assisted by behavioral test, electroencephalography (EEG) recording and analyzing, selectively neuronal manipulation and immunohistochemistry, we assessed the effects of DBS on the three septal subregions in kainic acid (KA)‐induced mouse seizure model. Results: DBS in the medial septum (MS) not only delayed generalized seizure (GS) development, but reduced the severity; DBS in the vertical diagonal band of Broca (VDB) only reduced the severity of GS, while DBS in the horizontal diagonal band of Broca (HDB) subregion showed no anti‐seizure effect. Notably, DBS in the MS much more efficiently decreased abnormal activation of hippocampal neurons. EEG spectrum analysis indicated that DBS in the MS and VDB subregions mainly increased the basal hippocampal low‐frequency (delta and theta) rhythm. Furthermore, ablation of cholinergic neurons in the MS and VDB subregions blocked the anti‐seizure and EEG‐modulating effects of septal DBS, suggesting the seizure‐alleviating effect of DBS was dependent on local cholinergic neurons. Significance: DBS in the MS and VDB, rather than HDB, attenuates hippocampal seizure by activation of cholinergic neurons‐augmented hippocampal delta/theta rhythm. This may be of great therapeutic significance for the clinical treatment of epilepsy with septal DBS. Plain Language Summary: The optical target of deep brain stimulation in the septum is still not clear. This study demonstrated that stimulation in the medial septum and vertical diagonal band of Broca subregions, but not the horizontal diagonal band of Broca, could alleviate hippocampal seizure through cholinergic neurons‐augmented hippocampal delta/theta rhythm. This study may shed light on the importance of precise regulation of deep brain stimulation therapy in treating epileptic seizures. [ABSTRACT FROM AUTHOR]

Emulsions in the form of creams, lotions, gels or foams are the most widely used personal care formulations to improve the condition and feel of the skin. Achieving an optimal balance between their performance, effectiveness and sensory profile is essential, with the sensory profile being a key factor in consumer satisfaction and the success of these products in the market. Well‐established methods using highly trained and semi‐trained panels (e.g. Spectrum descriptive analysis, Flash Profile method, Quantitative Descriptive Analysis method and ‘Check‐all‐that‐apply’) are available and commonly used for the sensory assessment of personal care products. Nevertheless, a common drawback among all these methods is their inherent cost, both in terms of financial resources and time requirements. In recent years, research studies have emerged to address this limitation by investigating potential correlations between tactile sensory attributes and instrumental data associated with the physical characteristics of topical formulations. In other words, significant efforts have been invested in the development of robust instrumental methods specifically designed to accurately predict the sensory description that a panel of assessors could establish. These methods are not only faster, cheaper and more objective compared to traditional sensory testing, but they can also be applied to formulations that have not undergone extensive safety and toxicological testing. This review summarizes the most relevant findings, trends and current challenges in predicting tactile sensory attributes of personal care emulsions based on instrumental parameters. [ABSTRACT FROM AUTHOR]

Based on the requirements of deep sealing and profile control for the excellent temperature and salt resistance on polyacrylamide microspheres, the Poly‐AM/AMPS was prepared depends on aqueous solution polymerization method to improving oil and gas recovery efficiency in low‐permeability and heterogeneous reservoirs resulted by water channeling. The key technical parameters were established through single‐factor experimental methods, and the chemical structure was studied by infrared spectrum analysis (FTIR), energy spectrum analysis, and x‐ray diffraction analysis, and then the thermal stability was investigated depends on the thermogravimetric (TG) and differential thermogravimetric (DTG) distribution curves, moreover, the particle size and distribution, microstructure, and surface morphology were further studied. As a result, the results confirmed that the molecular structure of Poly‐AM/AMPS meets the expected design, and the quality retention rate at 800°C is 17.4%, the median particle size of Poly‐AM/AMPS particles is 35.88 μm, and the particle size distribution range is about 1.94–497.8 μm. Further, the Poly‐AM/AMPS was modified by maleic anhydride, sodium styrenesulfonate, and dimethyl diallyl ammonium chloride through conventional functional strengthening and modification, modified by nano‐SiO2, GO, and S‐CaCO3 through nano‐functional strengthening and modification. Additionally, the functional strengthening and modification mechanism was studied depends on the FTIR, TG, and DTG methods. [ABSTRACT FROM AUTHOR]

We propose a new class of high‐order time‐marching schemes with dissipation control and unconditional stability for parabolic equations. High‐order time integrators can deliver the optimal performance of highly accurate and robust spatial discretizations such as isogeometric analysis. The generalized‐α$$ \alpha $$ method delivers unconditional stability and second‐order accuracy in time and controls the numerical dissipation in the discrete spectrum's high‐frequency region. We extend the generalized‐α$$ \alpha $$ methodology to obtain high‐order time marching methods with high accuracy and dissipation control in the discrete high‐frequency range. Furthermore, we maintain the original stability region of the second‐order generalized‐α$$ \alpha $$ method in the new higher‐order methods; we increase the accuracy of the generalized‐α$$ \alpha $$ method while keeping the unconditional stability and user‐control features on the high‐frequency numerical dissipation. The methodology solves k>1,k∈ℕ$$ k>1,k\in \mathbb{N} $$ matrix problems and updates the system unknowns, which correspond to higher‐order terms in Taylor expansions to obtain (3/2k)th$$ \left(3/2k\right)\mathrm{th} $$‐order method for even k$$ k $$ and (3/2k+1/2)th$$ \left(3/2k+1/2\right)\mathrm{th} $$‐order for odd k$$ k $$. A single parameter ρ∞$$ {\rho}^{\infty } $$ controls the high‐frequency dissipation, while the update procedure follows the formulation of the original second‐order method. Additionally, we show that our method is A‐stable, and for ρ∞=0$$ {\rho}^{\infty }=0 $$ we obtain an L‐stable method. Furthermore, we extend this strategy to analyze the accuracy order of a generic method. Lastly, we provide numerical examples that validate our analysis of the method and demonstrate its performance. First, we simulate heat propagation; then, we analyze nonlinear problems, such as the Swift–Hohenberg and Cahn–Hilliard phase‐field models. To conclude, we compare the method to Runge–Kutta techniques in simulating the Lorenz system. [ABSTRACT FROM AUTHOR]

Capillary force self‐assembly (CFSA) technology unfolds great potential in the fabrication of functional micro/nanostructures. To date, most self‐assembly methods focus on monolithic microstructure manipulation yet it remains a challenge to achieve precise localized control over the CFSA process of micro/nanostructures. Herein, a light‐regulated CFSA is proposed to realize the localized precise control of microstructures, leveraging on the synergistic effect of photothermally‐responsive hydrogel and self‐assembly technique. The micropillars with asymmetric cross‐linking densities can readily prepare by applying a rationally designed laser and laser‐exposing dosage, thereby realizing the on‐demand steering of their bending directions. Significantly, owing to the giant capillary force deriving from the evaporating water, above micropillars can successfully assemble into highly‐ordered chiral structures. Simulation coupling with fundamental hydrodynamics enables to shed light on the light steering principle over pillar's actuations. Last, on the basis of vortical dichroism spectra analysis, the chiral characteristics of light‐regulated self‐assembly including the chiral as well as the achiral self‐assembled microstructures are successfully deployed. This strategy provides an avenue for fabricating the localized controllable self‐assembly at the microscale and will bloom the field over metamaterials, microsensors, chiral optics, and so on. [ABSTRACT FROM AUTHOR]

Summary: Diatoms are a diverse group of phytoplankton usually dominating areas characterized by rapidly shifting light conditions. Because of their high growth rates and interesting biochemical profile, their biomass is considered for various commercial applications. This study aimed at identifying strains with superior growth in a photobioreactor (PBR) by screening the natural intraspecific diversity of ecotypes isolated from different habitats. We investigated the effect of PBR light fluctuating on a millisecond scale (FL, simulating the light in a PBR) on 19 ecotypes of the diatom Skeletonema marinoi isolated from the North Sea–Baltic Sea area.We compare growth, pigment ratios, phylogeny, photo‐physiological variables and photoacclimation strategies between all strains and perform qPCR and absorption spectra analysis on a subset of strains.Our results show that the ecotypes responded differently to FL, and have contrasting photo‐physiological and photoprotective strategies. The strains from Kattegat performed better in FL, and shared common photoacclimation and photoprotection strategies that are the results of adaptation to the specific light climate of the Kattegat area.The strains that performed better with FL conditions had a high light (HL)‐acclimated phenotype coupled with unique nonphotochemical quenching features. Based on their characteristics, three strains were identified as good candidates for growth in PBRs. [ABSTRACT FROM AUTHOR]

When compared to traditional seismic data acquisition, irregular blended acquisition significantly promotes the acquisition efficiency. Yet, the blending noise of subsampled blended data introduces new obstacles for the subsequent processing of seismic data. Due to the predictability of linear events in the frequency–space domain, the constructed Hankel matrices exhibit low‐rank characteristics. However, the blending noise of subsampled blended data increases the rank, so deblending and interpolation can be implemented via rank‐reduction algorithms such as the singular spectrum analysis. The significant computing cost of the singular value decomposition, however, makes the traditional singular spectrum analysis inefficient. An alternative algorithm, known as the randomized singular spectrum analysis, employs the randomized singular value decomposition instead of the traditional singular value decomposition for rank‐reduction. The randomized singular spectrum analysis significantly enhances the efficiency of the decomposition process, particularly when dealing with large Hankel matrices. There still remains some random noise when using the singular spectrum analysis or randomized singular spectrum analysis for subsampled blended data, because the noise subspace and signal subspace are coupled together. Thus, we incorporate a damping operator into the randomized singular value decomposition and propose a novel damped randomized singular spectrum analysis method. The damped randomized singular spectrum analysis combines the advantages of the randomized singular value decomposition and the damping operator to enhance the computational efficiency and suppress the remaining noise. Moreover, an iterative projected gradient descent strategy is introduced to achieve deblended and interpolated seismic data for subsequent processing. Examples from synthetic data and field data are used to demonstrate the effectiveness and superiority of the proposed damped randomized singular spectrum analysis method, which enhances the accuracy and efficiency during simultaneous deblending and interpolation. [ABSTRACT FROM AUTHOR]

Aims: Liquid biopsy (LBx)‐based next‐generation sequencing (NGS) of circulating tumour DNA (ctDNA) can facilitate molecular profiling of haematopoietic neoplasms (HNs), particularly when tissue‐based NGS is infeasible. Methods and Results: We studied HN LBx samples tested with FoundationOne Liquid CDx, FoundationOne Liquid, or FoundationACT between July 2016 and March 2022. We identified 271 samples: 89 non‐Hodgkin lymphoma (NHL), 43 plasma‐cell neoplasm (PCN), 41 histiocytoses, 27 myelodysplastic syndrome (MDS), 25 diffuse large B‐cell lymphoma (DLBCL), 22 myeloproliferative neoplasm (MPN), 14 Hodgkin lymphoma (HL), and 10 acute myeloid leukaemia (AML). Among 73.4% with detectable pathogenic alterations, median maximum somatic allele frequency (MSAF) was 16.6%, with AML (36.2%), MDS (19.7%), and MPN (44.5%) having higher MSAFs than DLBCL (3.9%), NHL (8.4%), HL (1.5%), PCN (2.8%), and histiocytoses (1.8%) (P = 0.001). LBx detected characteristic alterations across HNs, including in TP53, KRAS, MYD88, and BTK in NHLs; TP53, KRAS, NRAS, and BRAF in PCNs; IGH in DLBCL; TP53, ATM, and PDCD1LG2 in HL; BRAF and MAP2K1 in histiocytoses; TP53, SF3B1, DNMT3A, TET2, and ASXL1 in MDS; JAK2 in MPNs; and FLT3, IDH2, and NPM1 in AML. Among 24 samples, the positive percent agreement by LBx was 75.7% for variants present in paired buffy coat, marrow, or tissues. Also, 75.0% of pairs exhibited alterations only present on LBx. These were predominantly subclonal (clonal fraction of 3.8%), reflecting the analytical sensitivity of LBx. Conclusion: These data demonstrate that LBx can detect relevant genomic alterations across HNs, including at low clonal fractions, suggesting a potential clinical utility for identifying residual or emerging therapy‐resistant clones that may be undetectable in site‐specific tissue biopsies. [ABSTRACT FROM AUTHOR]

In this article, we propose a double reconfigurable intelligent surface (RIS)‐aided ambient backscatter communication (AmBC) network combined with non‐orthogonal multiple access (NOMA) technology, which not only successfully assists the base station (BS) in connecting with the cell edge user, but also enhances backscatter communication rate, energy efficiency, and spectrum efficiency. In an effort to obtain the highest backscatter communication rate, we design a RIS and BS‐based resource allocation problem which is solved by determining the optimal phase shifts of RISs and the optimal power allocation for signals of NOMA users. We break it down into two smaller challenges in order to discover the best solution. For one thing, we iterate the optimal phase shifts between the two RIS combinations using an alternating optimization technique. For another, the bisection method is used to provide the NOMA user with the ideal power allocation. Finally, the results of the simulation substantiate the viability of the proposed scheme. [ABSTRACT FROM AUTHOR]

Compared with Group VIB transition metal dichalcogenides (TMDs), Group IVB TMDs, specifically ZrX2, have exhibited superior carrier mobility, rendering them highly promising for developing innovative electron devices. The application of high‐pressure has been identified as an effective approach for altering the physical properties of TMDs by manipulating their lattice and electronic structures. This subject has attracted considerable attention within the scientific community. In this investigation, in situ high‐pressure Raman scattering and UV‐visible absorption spectra analysis are conducted to examine the lattice and electronic structural changes in multilayer ZrS2. Raman spectroscopy analysis reveals two phase transitions occurring at 3.65 and 10.95 GPa. Concurrently, the optical absorption findings reveal a distinct transformation in both the optical energy gap and Urbach energy at 3.34 GPa, highlighting the accompanying lattice and electronic structural changes in ZrS2 under high‐pressure. Moreover, these lattice and electronic structural changes are found to be irreversible, indicating the potential utility of compressed ZrS2 in optoelectronic devices. [ABSTRACT FROM AUTHOR]

Although the potential of Raman Optical Activity (ROA) spectroscopy in the field of organic and inorganic materials research has been well demonstrated, its practical application is still limited. This work shows historical background, current state of the art and challenges of ROA spectroscopy facing scientists today. Expectations and development prospects for the coming years are also discussed. Efforts have already been made to improve but also to properly interpret the ROA signal when the ROA technique is combined with other spectroscopies (i.e., ROA/Electronic Circular Dichroism and ROA/Circularly Polarized Luminescence). The paper shows how to intensify the ROA effect to shorten the spectrum accumulation time, control possible artefacts and support the analysis of ROA spectra with actual and new theoretical approaches. However, the challenge is to increase the interest in this technique among the academic community, develop reliable protocols and adapt them for practical use. National and international research networks can significantly contribute to the growth of methodologies and standardization in areas in which the ROA has so far been little used. This paper presents a perspective vision for the future progress of ROA alongside other chiroptical methods. [ABSTRACT FROM AUTHOR]

Rank‐reduction‐based simultaneous random noise attenuation and three‐dimensional seismic‐data interpolation has recently become a hot topic in reflection seismology. However, the rank of traditional methods is fixed without considering the variation of signal‐to‐noise ratio on different frequency components, leading to serious residual noise and further affecting the following processing and interpretation tasks. In addition, traditional methods also heavily rely on the application of singular value decomposition technique for rank reduction, which is proven to be computationally expensive for large‐scale data. Thus, a fast‐adaptive rank‐reduction method is proposed in this study. First, the information entropy theory is introduced to adaptively select the optimal rank at various frequencies by calculating the increment of singular entropy. Second, we propose a fast Random Block Krylov algorithm and a subspace multiplexing technique to replace the singular value decomposition algorithm used in traditional methods. The proposed method can significantly improve computational efficiency and yield better seismic‐data reconstruction performance than traditional methods. Applications of the proposed approach on both synthetic and field seismic data demonstrate its superior performance over a well‐known rank‐reduction‐based method, that is the random multi‐channel singular spectrum analysis, in terms of recovered signal‐to‐noise ratio and visual view. [ABSTRACT FROM AUTHOR]

Ocean bottom seismometer data usually contain a large amount of random noise, which seriously reduces the signal‐to‐noise ratio of the data and affects subsequent imaging. Hence, random noise attenuation is one of the most essential steps in ocean bottom seismometer data processing. In this paper, a novel approach is proposed to attenuate the marine seismic random noise of ocean bottom seismometers based on a six‐dense‐layer denoising autoencoder. We input the t−x$t-x$ domain data into the denoising autoencoder, the encoder compresses the signal and noise and extracts the main features and the decoder finally reconstructs the denoised data with the same dimension as the input. In this approach, because few raw labelled examples are available, we first constructed the pretraining, training and test data sets by patch processing. Then, we pretrained the encoder based on clean synthetic seismic data through unsupervised learning and pretrained the decoder based on noisy synthetic seismic data through supervised learning. Next, the pretrained model was fine‐tuned with the encoder–decoder on a raw seismic data set in an unsupervised manner. Finally, we used the model to attenuate the random noise in raw ocean bottom seismometer data for testing. Synthetic and raw examples are used to compare the f−x$f-x$ deconvolution, multichannel singular spectrum analysis, deep denoising autoencoder and substep deep denoising autoencoder approaches. Experimental tests demonstrate that the proposed method has higher processing efficiency and precision. [ABSTRACT FROM AUTHOR]

Analysis of the spectrum of inelastically scattered electrons in XPS has been used for decades to determine the structure of materials on the nanoscale. Using the higher photon energies available in HAXPES, the method was recently shown to determine structures rather accurately with a more than 100 nm probing depth. In this paper, these HAXPES applications are briefly reviewed. Only two parameters are required for the analysis, namely, the inelastic mean free path and the cross section for inelastic electron scattering. We also discuss in detail how these parameters are best selected. [ABSTRACT FROM AUTHOR]

Compared with Group VIB transition metal dichalcogenides (TMDs), Group IVB TMDs, specifically ZrX2, have exhibited superior carrier mobility, rendering them highly promising for developing innovative electron devices. The application of high‐pressure has been identified as an effective approach for altering the physical properties of TMDs by manipulating their lattice and electronic structures. This subject has attracted considerable attention within the scientific community. In this investigation, in situ high‐pressure Raman scattering and UV‐visible absorption spectra analysis are conducted to examine the lattice and electronic structural changes in multilayer ZrS2. Raman spectroscopy analysis reveals two phase transitions occurring at 3.65 and 10.95 GPa. Concurrently, the optical absorption findings reveal a distinct transformation in both the optical energy gap and Urbach energy at 3.34 GPa, highlighting the accompanying lattice and electronic structural changes in ZrS2 under high‐pressure. Moreover, these lattice and electronic structural changes are found to be irreversible, indicating the potential utility of compressed ZrS2 in optoelectronic devices. [ABSTRACT FROM AUTHOR]

A fundamental pattern in ecology is that smaller organisms are more abundant than larger organisms. This pattern is known as the individual size distribution (ISD), which is the frequency distribution of all individual body sizes in an ecosystem.The ISD is described by a power law and a major goal of size spectra analyses is to estimate the exponent of the power law, λ. However, while numerous methods have been developed to do this, they have focused almost exclusively on estimating λ from single samples.Here, we develop an extension of the truncated Pareto distribution within the probabilistic modelling language Stan. We use it to estimate multiple λs simultaneously in a hierarchical modelling approach.The most important result is the ability to examine hypotheses related to size spectra, including the assessment of fixed and random effects, within a single Bayesian generalized mixed model. While the example here uses size spectra, the technique can also be generalized to any data that follow a power law distribution. [ABSTRACT FROM AUTHOR]

Built‐up land changes along slope gradients (BCSG) are widespread globally, driven by natural environmental and socio‐economic variations. This process has profound effects on vegetation cover and is closely related to the United Nations Sustainable Development Goals. However, the mechanisms involved in the BCSG remain to be elucidated, and the impacts of BCSG on vegetation cover need to be quantified. The BCSG from 1990 to 2020 was described through slope spectrum analysis by taking the Three Gorges Reservoir Area (TGRA) as an example. Then, the Normalized Difference Vegetation Index (NDVI) was used as an indicator of vegetation cover, and its influence by BCSG was explored through a multiple linear regression model. The built‐up land in the TGRA from 1990 to 2020 was first dominated by slope climbing (SC) and then by horizontal expansion, and the intensity of built‐up land SC showed a general trend of weakening over time. During the 30 years, the intensity of built‐up land SC weakened and then strengthened in townships with mainly intermountain plains, while gradually decreasing in townships with mainly hills and townships with mainly mountains. Socio‐economic factors, natural factors, and regional special events drive the BCSG in TGRA. Built‐up land SC in the TGRA will have a negative impact on NDVI but to a progressively lesser degree from 1990 through 2020. The built‐up land SC in townships with mainly hills and mountains has a negative effect on NDVI. The built‐up land SC in townships with mainly intermountain plains has a positive impact on NDVI. These results can provide a scientific basis for formulating reasonable vertical management policies for built‐up land and help reduce the ecological risks caused by land development. [ABSTRACT FROM AUTHOR]

The response spectrum method has gained widespread acceptance in practical applications owing to its favorable compromise between accuracy and practical efficiency. The method predicts the peak responses of multi‐degree‐of‐freedom (MDOF) systems by combining modal responses. The Square Root of the Sum of Squares (SRSS) and Complete Quadratic Combination (CQC) rules are commonly used for modal combinations. However, it has been widely known that these rules have limitations in accurately predicting responses influenced by higher modes and cross‐modal correlations. To improve the accuracy of the response spectrum analysis method for building structures, this paper proposes a Deep learning‐based modal Combination (DC) rule by introducing modal contribution coefficients predicted by a deep neural network (DNN) model. The DC rule enhances prediction accuracy by considering the characteristics of ground motion and the dynamic properties of a structural system. The DC rule provides more accurate predictions than the conventional rules, particularly for irregular response spectra and responses affected by higher modes. The efficiency and applicability of the DC rule are demonstrated by numerical investigations of multistory shear buildings and steel frame structures with regular and irregular shapes. The source codes, data, and trained models are available for download at https://github.com/tyongkim/ERD2. [ABSTRACT FROM AUTHOR]

Vertical extensions of existing buildings can be realized through Intermediate Isolation System (IIS): the extension, equipped with a base isolation system on the rooftop of the existing building, can work as a mass damper, thus reducing the seismic demand on the old structure. The idea proposed in this paper is to predict the elastic or inelastic response of the existing structure in the IIS configuration by means of the results of simple linear analyses. Parametric response spectrum analyses are performed on simplified two degree‐of‐freedom models by varying the mass ratio and the periods of both the existing building and the new isolated vertical extension. So‐called IIS design spectra are derived, and the results are provided as design charts. Given the period of the existing building and the mass ratio, the period of the new isolated vertical extension is selected to obtain the required/desired response of the existing building. For existing buildings working in the elastic field, the designer can derive the response of the existing building by utilizing the IIS design spectra as design charts. For existing building working in the inelastic field, the design charts can still be adopted, though within a more complex procedure, which accounts for two limit behaviors that the extended building exhibits in the inelastic field. The outlined design procedure is applied to some case studies and validated through the comparison with the results of nonlinear time history analyses. [ABSTRACT FROM AUTHOR]

We propose a mean field game model to study the stability of production adjustment by extending a kind of linear quadratic Gaussian game in large population systems. First, we present the model's equilibrium solutions by a backward HJB equation and a forward FPK equation. Second, we employ the local perturbation method to transform the nonlinear problem into a linear one to study the solutions' stability. Third, we use the spectrum and contraction analyses to study the stationary solutions' linear stability. At last, we validate the results by the numerical simulation. The results show that the additional cost coefficient and noise intensity affect the system's stability. If the additional cost coefficient and the noise intensity are large enough for firms to change their outputs, then firms will try to reduce their production adjustment and remain stable long-term. [ABSTRACT FROM AUTHOR]

The light transmittance measurement method, which is used to characterize smoke characteristic signal of solid rocket motor plume, can provide important reference for development and design of low smoke characteristic signal solid propellants and motors. The light transmittance measurement method of solid rocket motor plume based on laser modulation spectrum analysis is proposed in this paper. By using a 405 nm laser as the light source and a narrow‐band filter detection method, the influence of plume radiation on the measurement of light transmittance of solid rocket motor plume smoke can be minimized. Additionally, combined with the laser modulation spectrum analysis technology, the signal amplitude is selected by the laser modulation frequency to improve the signal‐to‐noise ratio of the signal. Compared with the laser constant current measuring mode, laser high‐frequency modulation measuring mode with spectrum analysis effectively improves the optical transmittance measurement accuracy. Based on this, a solid rocket motor plume smoke transmittance test system is developed to measure the plume smoke of standard test motors with different propellants and combustion chamber pressures. The results demonstrate that the system can effectively measure the light transmittance of the plume smoke. The light transmittance of solid rocket motor plume can be increased by reducing the aluminum content of solid propellant or increasing the pressure of the combustion chamber. Thus, this research provides an effective measuring tool for evaluating smoke concentration of solid rocket motor plume, which is beneficial to develop low smoke characteristic signal solid propellants and motors. [ABSTRACT FROM AUTHOR]

Erythrocyte rheological properties contribute to the dynamic regulation of vascular resistance to flow shear force, facilitating blood delivery from the heart to peripheral tissues. Despite improved physical performance, the effects of eccentric cycling training (ECT) on erythrocyte rheological characteristics remain unclear. This study investigates the distinct effects of ECT and concentric cycling training (CCT) on muscular hemodynamic and erythrocyte rheological responses to exercise. Thirty‐nine sedentary healthy males were randomly assigned to either ECT (n = 13) or CCT (n = 13) at 45%–70% of the maximal workload for 30 min/day, 5 days/week for 6 weeks, or to a control group (n = 13) that did not receive any exercise intervention. A graded exercise test (GXT) was performed before and after the intervention. Muscular hemodynamic and erythrocyte rheological responses to the GXT were determined by near‐infrared spectroscopy and ektacytometry, respectively. Both ECT and CCT significantly enhanced perfusion (Δ[THb]VL) and O2 extraction (Δ[HHb]VL) in vastus lateralis during GXT. Before training, an acute GXT significantly reduced erythrocyte deformability and increased aggregability, whereas after 6 weeks of either ECT or CCT, the extent of erythrocyte rheological changes caused by GXT was diminished. Moreover, CCT elicited higher improvements in cardiac output (CO), VO2, and work‐rate at peak performance than ECT. In hierarchical regression, the change of maximal CO was the most influential factor affecting VO2max following CCT. In contrast, enhanced VO2max was significantly associated with Δ[HHb]VL and erythrocyte aggregability/deformability in ECT. Although CCT is superior to ECT for increasing aerobic capacity, either ECT or CCT effectively enhances aerobic efficiency by improving muscular hemodynamic and erythrocyte rheological responses to exercise. Highlights: Although concentric cycling training (CCT) is superior to eccentric cycling training (ECT) for increasing aerobic capacity, the two regimens effectively enhance aerobic efficiency by improving hemodynamic or/and hemorheological response(s) to exercise.ECT increases blood O2 delivery to and utilization by contracting muscles, while having lower exertional cardiovascular demand compared to CCT.Cardiac hemodynamic function is the most dominant factor affecting the change of aerobic capacity caused by CCT.Muscular hemodynamic and erythrocyte rheological functions are meaningfully associated with aerobic efficiency mediated by ECT. [ABSTRACT FROM AUTHOR]

In this introduction to the Journal of Raman Spectroscopy special issue "Advanced Raman procedures applied to natural/cultural heritage and forensic questions: Mobile set‐up, data treatment and associated techniques," the aim is to assess the state of the art in the field and to highlight potential new perspectives. The novel approaches employed in the published papers are described and can be grouped as such: application of multivariate statistical analysis to Raman spectra, use of mobile instrumentations directly in situ for both cultural and forensic contexts, tackling with optics and spectral range issues, and coupling with mobile instrumentations based on different analytical techniques. [ABSTRACT FROM AUTHOR]

Chemical states of carbon in terrestrial (meta) sediments and carbonaceous chondrites gather attention as a geothermometer. As a nondestructive analytical method, Raman spectroscopy has been widely used to study their electronic properties, crystallinity, and structural defects through so‐called D and G bands. For the analysis of Raman spectra, a common problem is coexistence of a fluorescence background, which should be subtracted prior to the peak‐fitting analysis. However, we recently faced a problem that the band shape noticeably changed depending on the background function assumed although the background seemed to be well subtracted at a first glance regardless of the choice of the background function. For the application of the Raman spectroscopy as a geothermometer, a standard background subtraction method must be established to suppress the arbitrariness. In the present study, Raman spectra of seven carbon‐containing natural samples, whose background intensities were significantly different, were measured, and their background shape was evaluated by first‐, second‐, and third‐order polynomials. The results indicated that the third‐order polynomial was necessary and sufficient as a standard background function. Importantly, although lower order polynomials seem to successfully fit the background at a first glance, they falsely caused dispersion of the shoulder band shape. [ABSTRACT FROM AUTHOR]

Identification of similar and dissimilar spectra is an important part of analyzing X‐ray photoelectron spectroscopy (XPS) images. Cluster analysis (CA) is a commonly used exploratory data analysis (EDA) method that groups similar spectra in a data set. CA can be performed in either an agglomerative fashion, for example, using Ward's method, which involves successively linking together/clustering the most similar spectra in a data set, or in a divisive fashion, for example, using the K‐means approach, which involves partitioning all the data into a specified number of clusters. In this note, we show the application of CA to an XPS image dataset. The use of Ward's method identified two major clusters in the image, where one of the clusters appeared as two subclusters. The K‐means image based on two clusters agrees well with previous analyses of the same image. The average spectra corresponding to clusters helped confirm the assignments made by the CA algorithms, as did a multivariate curve resolution (MCR) analysis of the interior region identified in our cluster analysis. "Elbow" plots can help determine the number of clusters to keep in K‐means clustering. The combination of the agglomerative and divisive forms of CA, where the first informs the second, can be effective in revealing the structures of XPS image datasets. The Procrustean bed is a metaphor for overfitting and underfitting in EDA. [ABSTRACT FROM AUTHOR]

Nano‐scale laser beam size and its shape information are essential parameters in most optics‐based precision measurements and nano‐scale material processing. It is also quite challenging to measure nano‐size optical beams accurately for both open experiments and at compact workplace of microscope due to various instrumental factors. Outside of the visible spectrum, usually wavelength‐sensitive fluorescence markers and composite materials are used to read the laser beam profile. In this article, a cost‐effective carbon nano‐particles (CNPs) film has been developed from candle soot. Furthermore, the developed bio‐carbon soot film is encapsulated with optically transparent composite polymer on aqueous media to measure sub‐micron size spot of a low‐power laser. Field emission scanning electron microscopy, optical spectrum analysis, Fourier transform infrared spectroscopy, UV‐visible spectroscopy, differential scanning calorimetry and thermogravimetric analysis techniques have been performed to characterize the developed CNPs film and optimized its functionality. The fabricated film has been used to measure sub‐micron laser beam size. Due to the wide absorption spectrum of the developed bio‐CNPs film, the sensitivity region for measurement lies within both visible and beyond the visible spectrum. [ABSTRACT FROM AUTHOR]

This study investigates the impact of atmospheric cold plasma on locust bean gum (LBG) rheology using a multi‐pin configuration. LBG undergoes plasma treatment at 30 kV for durations of 10, 20, and 30 min. Evaluation of color attributes and total color difference revealed enhancements in LBG post‐plasma treatment. The linear viscoelastic region, determined at a 0.5% strain, demonstrated improved storage modulus (G′) and loss modulus (G″) concerning frequency compared to the control. Additionally, viscosity and shear stress displayed an inverse relationship with increasing shear rate, indicating the pseudoplastic nature of LBG samples. Consistent trends in G′ and G″ values of treated LBG were observed across three temperature stages, except for the 30 kV and 10 min. Infrared spectra analysis of plasma‐treated LBG samples indicated the preservation of most polysaccharide groups, with no significant peak alterations. Overall, cold plasma treatment modifies LBG rheology, making it suitable for diverse food applications. [ABSTRACT FROM AUTHOR]

Taking the megacity of Beijing as an example, a short‐time Fourier transform (STFT) method was employed to extract the multi‐timescale evolution pattern of the canopy urban heat island intensity (CUHII) during 2000–2020. The STFT of CUHII showed a close relationship between the evolution of the CUHII in Beijing and the background meteorological forcing at intra‐annual, weather and intra‐daily scales. The intra‐annual‐scale spectrum of CUHII exhibited an increasing trend with obvious seasonal variation of the canopy urban heat island (CUHI). The intra‐daily‐scale spectrum of CUHII showed an increasing trend with the nighttime CUHI developing faster. Increasing Western Pacific Subtropical High intensity can enhance the seasonal and diurnal fluctuations of CUHII. The weather‐scale spectrum of CUHII is controlled by weather system evolution, showing that the frequency of cold/heat waves (CWs/HWs) in Beijing was significantly negatively correlated with the weather‐scale spectral intensity of the CUHII. CWs and HWs can increase the CUHII for a long duration. Plain Language Summary: The canopy urban heat island (CUHI) phenomenon can affect human health and the ecological environment, and its multi‐timescale variability brings great uncertainty to the study of urban climates worldwide. In this study, taking the megacity of Beijing as an example, a novel short‐time Fourier transform (STFT) method was used to extract the multi‐timescale pattern of the CUHI intensity (CUHII) during 2000–2020. The STFT of CUHII showed a close relationship between the CUHI and the background meteorological forcing at intra‐annual, weather and intra‐daily scales. The intra‐annual spectrum of CUHII showed an increasing trend with a V‐shaped mode. The local climatic backgrounds of different cities can lead to differences in the seasonal development of the CUHI. The intra‐daily spectrum of CUHII showed an increasing trend due to the asymmetry in the day/night development of the CUHI. Increasing Western Pacific Subtropical High Intensity can enhance the seasonal and diurnal fluctuations of CUHII. The weather‐scale spectrum of CUHII was mainly controlled by weather system evolution, showing that cold waves and heat waves can increase the CUHII over a long duration. Our findings indicate that the evolution of CUHII is a nonlinear and complex process that is directly related to multi‐timescale background climate forcing. Key Points: Using a short‐time Fourier transform to study the multi‐timescale evolution of the canopy urban heat island intensity (CUHII)Close relationships existed between CUHII and the background meteorological forcing at intra‐annual, intra‐daily, and weather scalesThe frequency of cold/heat waves in Beijing showed a significant negative correlation with the weather‐scale spectral intensity of the CUHII [ABSTRACT FROM AUTHOR]

Summary: The present study aimed to investigate the impact of TGase cross‐linking on the flavour characteristics, particularly focusing on its ability to reduce bitterness in enzymatically digested Alaska Pollock framework (APF) hydrolysates using Protease A 'Amano' 2SD (A2SD) and Protease A 'Amano' 6SD (A6SD). Electronic tongue results showed that the umami was enhanced, accompanied by a reduction in both bitterness and bitter aftertaste. The contents of glutamic acid (Glu) and nucleotides (AMP, IMP and GMP) exhibited significant differences among all treatment groups (P < 0.05). There was a notable increase in the types and relative concentrations of alcohols, ketones, alkanes and aldehydes in the cross‐linked APF enzymatic hydrolysate. The Fourier transform infrared spectroscopy, ultraviolet spectrum and fluorescence spectrum analyses indicate that TGase cross‐linking leads to a reduction in the exposure of hydrophobic amino acid residues. The surface hydrophobicity of HA2SD‐C and HA6SD‐C exhibited a significantly lower level compared with that of HA2SD and HA6SD. The present study presents an effective approach for mitigating the bitter taste of aquatic hydrolysate, thereby positively contributing to the advancement and utilisation of this valuable resource. [ABSTRACT FROM AUTHOR]

Objectives: To compare the filler weight percentage (wt%), filler and resin composition, flexural strength, modulus, and hardness of several 3D‐printed resins to direct and indirect restorative materials. Materials and Methods: Four 3D‐printed resins (C&B MFH, Ceramic Crown, OnX, and OnX Tough), one milled resin composite (Lava Ultimate), one conventional composite (Filtek Supreme), and one ceramic (IPS e.max CAD) were evaluated. Filler wt% was determined by the burned ash technique, and filler particle morphology and composition were analyzed by scanning electron microscopy and energy‐dispersive spectroscopy, respectively. Organic resin composition was analyzed by Fourier transform infrared spectroscopy. Three‐point bend flexural strength and modulus of the materials were determined by ISO 4049 or ISO 6872. Vickers microhardness was measured. Data were compared with a one‐way analysis of variance (ANOVA) and Tukey post hoc analysis. Linear regression analysis was performed for filler wt% versus flexural strength, modulus, and hardness. Results: 3D‐printed resins were composed of various sized and shaped silica fillers and various types of methacrylate resins. Significant differences were found among filler wt% with some materials around 3% (C&B MFH), others between 33% and 38% (OnX Tough and OnX), others around 50% (Ceramic Crown), and some around 72% (Filtek Supreme and Lava Ultimate). All 3D‐printed resins had significantly lower flexural strength, modulus, and hardness than the conventional and milled resin composites and ceramic material (p < 0.001). Filler wt% demonstrated a linear relationship with modulus (p = 0.013, R2 = 0.821) and hardness (p = 0.018, R2 = 0.787) but not flexural strength (p = 0.056, R2 = 0.551). Conclusions: 3D‐printed resins contain from 3% to 50% filler content. Filler wt% alone does not affect flexural strength, but strength may be affected by resin composition as well. Although the 3D‐printed resins had lower flexural strength, modulus, and hardness than milled and conventional composite and ceramic, they demonstrated nonbrittle plastic behavior. Clinical Significance: The properties of 3D‐printed resins vary based on their composition, which affects their clinical applications. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the effect of different hydrofluoric acid concentrations and etching times on the surface, chemical composition and microstructure of lithium disilicate. Material and Methods: Ninety specimens of pressed lithium disilicate (LDS) were obtained (IPS e.max Press, Rosetta SP and LiSi Press). The specimens of each material were divided in two groups according to the hydrofluoric acid concentration: 5% and 10% (n = 15/group), and subdivided according to the etching time: 20, 40 and 60 s (n = 5/group). Crystalline evaluations and chemical composition were performed through x‐ray diffraction (XRD) and energy‐dispersive x‐ray spectroscopy (EDS), respectively. Microstructural analyses were performed by scanning electron microscope (SEM), surface roughness (Ra), and material thickness removal evaluation. Thickness removal and Ra data were analyzed by ANOVA and Tukey test (p < 0.05). Results: XRD demonstrated characteristic peaks of lithium disilicate crystals, lithium phosphate and of a vitreous phase for all materials. EDS identified different compositions and SEM confirmed different surface responses to acid etching protocols. Material and etching time influenced Ra and material thickness removal (p < 0.05). Conclusion: Hydrofluoric acid concentration and etching time affect the surface characteristics of LDS differently. LiSi Press presented higher resistance to hydrofluoric acid etching compared to e.max Press and Rosetta SP. Clinical Significance: Applying the appropriate etching protocol is pivotal to avoid excessive material removal and to prevent jeopardize the mechanical and optical properties of the material. [ABSTRACT FROM AUTHOR]

The discovery of compounds with low thermal conductivity and the understanding of their microscopic mechanisms are of great challenges and scientific significance. Herein, we report a unique ternary sulfide compound, Cu3BiS3, in which all Cu atoms are coordinated within a two‐dimensional [CuS3] triangle plane. This local coordination leads to efficient out‐of‐plane phonon scattering and an ultralow thermal conductivity. Through DFT phonon spectrum calculations and analyses, we reveal that the lowest vibration frequency decreases from 2 THz for high‐dimensional [CuS4] tetrahedral coordinated Cu atoms in CuBiS2 (CN=4, with an average Cu−S bond length of 2.328 Å) to 1.5 THz for low‐dimensional [CuS3] triangular coordinated Cu atoms in Cu3BiS3 (CN=3, with a shorter Cu−S bond length of 2.285 Å). This is due to the out‐of‐plane thermal vibration of the Cu atoms in the latter. Consequently,Cu3BiS3 exhibits one of the lowest values of κlat (0.32 W/m K) among its peer, with a 36 % reduction compared to CuBiS2 (0.50 W/m K). This groundbreaking discovery highlights the significant role of 2D local coordination in reducing thermal conductivity through characteristic out‐of‐plane phonon scattering, while also contributing to a large Grüneisen parameter (2.06) in Cu3BiS3. [ABSTRACT FROM AUTHOR]

Background and Aims: Axonal forms of Charcot‐Marie‐Tooth disease (CMT) are classified as CMT2, distal hereditary motor neuropathy (dHMN) or hereditary sensory neuropathy (HSN) and can be caused by mutations in over 100 genes. We presently aimed to investigate for the first time the genetic landscape of axonal CMT in the Greek population. Methods: Sixty index patients with CMT2, dHMN or HSN were screened by a combination of Sanger sequencing (GJB1) and next‐generation sequencing custom‐made gene panel covering 24 commonly mutated genes in axonal CMT. Results: Overall, 20 variants classified as pathogenic or likely pathogenic were identified in heterozygous state in 20 index cases, representing 33.3% of the cohort. Of these, 14 were known pathogenic/likely pathogenic and six were designated as such according to ACMG classification, after in silico evaluation, testing for familial segregation and further literature review. The most frequently involved genes were GJB1 (11.7%), MPZ (5%) and MFN2 (5%), followed by DNM2 (3.3%) and LRSAM1 (3.3%). Single cases were identified with mutations in BSCL2, HSPB1 and GDAP1. Interpretation: A wide phenotypic variability in terms of severity and age of onset was noted. Given the limited number of genes tested, the diagnostic yield of the present panel compares favourably with studies in other European populations. Our study delineates the genetic and phenotypic variability of inherited axonal neuropathies in the Greek population and contributes to the pathogenicity characterization of further variants linked to axonal neuropathies. [ABSTRACT FROM AUTHOR]

High‐resolution interference pattern images are vital for spatial heterodyne Raman spectroscopy to produce quality Raman spectra with a good signal‐to‐noise ratio. A sought‐after super‐resolution algorithm can enhance Raman interference pattern images, reducing reliance on expensive imaging sensors. This enables miniaturization and portability for point‐of‐care testing. This study proposes a generative adversarial network (GAN)‐based super‐resolution reconstruction algorithm explicitly designed for Raman interference patterns. Employing GAN adversarial training, the algorithm effectively reconstructs interference pattern images at higher resolution, improving Raman spectra signal‐to‐noise ratio. Considering Raman spectra analysis mainly focuses on characteristic peaks, a Raman characteristic peak‐focused network training scheme is used. For instance, acetaminophen is studied with two selected Raman characteristic peaks centered at 388 and 858 cm−1. These peaks are observed in Fourier transformed Raman spectra from corresponding low‐resolution interference pattern images obtained by down‐sampling high‐resolution ones by twofold and fourfold. The proposed GAN‐based algorithm successfully reconstructs low‐resolution interference patterns into high‐resolution ones, achieving high R‐square values (96.05% for twofold and 91.1% for fourfold). This innovation holds potential for point‐of‐care applications, like noninvasive blood glucose concentration measurements, enabling cost‐effective, portable Raman spectrometers with improved capabilities. [ABSTRACT FROM AUTHOR]

We introduce two novel nonparametric forecasting methods designed for functional time series (FTS), namely, functional singular spectrum analysis (FSSA) recurrent and vector forecasting. Our algorithms rely on extracted signals obtained from the FSSA method and innovative recurrence relations to make predictions. These techniques are model‐free, capable of predicting nonstationary FTS and utilize a computational approach for parameter selection. We also employ a bootstrap algorithm to assess the goodness‐of‐prediction. Through comprehensive evaluations on both simulated and real‐world climate data, we showcase the effectiveness of our techniques compared to various parametric and nonparametric approaches for forecasting nonstationary stochastic processes. Furthermore, we have implemented these methods in the Rfssa R package and developed a shiny web application for interactive exploration of the results. [ABSTRACT FROM AUTHOR]

On‐chip photonic filters are one of the most important elements for spectrum manipulation in various optical systems, including wavelength‐division multiplexing and spectrum analysis. Currently, it is still very challenging to achieve scalable photonic filters with flexibly‐designed bandwidths, low excess losses, flat tops, and ultra‐wide free‐spectral ranges (FSRs). Here an unprecedented silicon photonic filter is proposed and demonstrated with high performances by using apodised antisymmetric multimode subwavelength gratings (MSWGs) structures. For the present silicon photonic filter, the MSWGs enable the index engineering in the Bragg lattice, which easily manipulates the coupling coefficient, the local effective index, and the mode profile flexibly. As a result, the strong side lobes of the grating filter are efficiently suppressed, while the bandwidth can be designed flexibly and the FSR is free. The fabricated silicon photonic filter is FSR‐free and shows a low excess loss of <1 dB and a high sidelobe suppression ratio of 20–40 dB. [ABSTRACT FROM AUTHOR]

Although a wide variety of response spectrum methods have been developed to estimate peak horizontal building responses, much less attention has been devoted to study the applicability of those methods for the vertical direction or to develop new methods to estimate peak vertical building responses. Vertical building responses can be significant for structures located close to the earthquake rupture, and for buildings with fundamental period of vibration within the range of most energy content of the vertical component of the ground motion (typically 0.05 to 0.15 s). The frequency content of the vertical component is significantly different to that in the horizontal components; thus, it is not clear if previous methods are applicable. We present a new alternative response spectrum analysis (RSA) method to estimate absolute accelerations in the vertical direction, which is a modified version of a previously studied modal combination rule developed for the horizontal components of motion. This formulation is derived based on the use of modal absolute accelerations, and we compare it to the traditional complete quadratic combination (CQC). In the proposed method, we develop simplified equations to estimate the necessary correlation coefficients for the vertical direction which are calibrated to fit empirical correlations computed from the vertical response of single degree of freedom systems subjected to a set of 90 vertical components of recorded ground motions. We also compute these correlations by using an improved power spectral density (PSD) function, which is as an enhanced version of the modified Kanai‐Tajimi PSD to represent the frequency content in the vertical direction which differs from that in the horizontal direction. To evaluate the proposed modal combination rule, we compare the RSA results to those obtained using response history analyses (RHA) of peak responses for a simplified model consisting of a prismatic bar fixed only at one end, as well as for 2D frames. We show that the proposed modal combination rule can estimate peak building responses with higher accuracy than the commonly used CQC modal combination rule, for any general building configuration at any structural location. [ABSTRACT FROM AUTHOR]

Herein, an efficient methodology for the homogeneous manganese‐catalysed transfer hydrogenation of N‐heterocycles by using ammonia‐borane as a hydrogen source under mild reaction conditions is reported. Good to excellent isolated yields are achieved by applying a PNP manganese pincer complex. In the reaction, 1,2‐dihydroquinoline is detected as intermediate by NMR spectra analysis and deuterium labelling experiment. The catalytic reaction likely proceeded by an outer‐sphere pathway based on the bifunctional pincer complex. [ABSTRACT FROM AUTHOR]

A series of LaCaGaO4:xBi3+,yEu3+ (x = 0.002–0.04, y = 0.02–0.45) phosphors with adjustable emission colors were synthesized by high‐temperature solid‐state reaction. The samples were identified as pure phases by X‐ray diffraction and Rietveld refinement, and the crystal structures were analyzed in detail. The LaCaGaO4:xBi3+ phosphor shows an intense blue emission under near‐ultraviolet excitation, originating from the 3P1 → 1S0 transition. The spectrum analysis reveals that the Bi3+ ions occupy two luminescence centers in the LaCaGaO4 host and that energy transfer can occur. A model of the energy transfer between the Bi3+ and Eu3+ ions was also created and studied in detail. As the Eu3+‐concentration increased, the emission color of the LaCaGaO4:0.005Bi3+,yEu3+ phosphor changed from blue to pink to red. In addition, the fluorescence lifetime, quantum yield, thermal stability, and other properties of the phosphors were characterized and analyzed. Finally, two white light‐emitting diode devices with Ra values of 96.6 and 95 and correlated color temperatures of 4578 and 3324 K were fabricated, indicating the potential of phosphors for warm white lighting applications. [ABSTRACT FROM AUTHOR]

Microspectrometers have numerous applications in mobile optical sensing due to their dramatic advantages of compact size, light weight, and low power consumption. Reconstructive spectrometers, based on computational algorithms, have garnered considerable interest as they exhibit superior resolution or spectral bandwidth. However, existing reconstructive spectrometer designs face challenges in spectral applicability, algorithm robustness, and the resolution‐bandwidth limit. Here, a reconstructive spectrometer that utilizes a microring resonator (MRR) is proposed to achieve compressed sensing in hardware by decomposing an arbitrary continuous spectrum into a series of simple comb spectra. Owing to the presparse operation of the MRR, one needs to construct the comb spectra with a known line shape, only leaving the amplitude to be solved. Consequent random gratings measure the comb spectra, which are reconstructed with high robustness. Thanks to the independent engineering of spectral resolution and bandwidth, the approach breaks the traditional resolution‐bandwidth limit. A narrowband signal of a dual peak at 0.2 nm and a broadband spectrum with a large spectral bandwidth of 60 nm and 300 spectral channels using only eight physical channels is retrieved, achieving an ultrahigh reconstructive compression ratio of 37.5. This work opens up the possibility of on‐site spectral spectroscopy applications for the lab‐on‐a‐chip system. [ABSTRACT FROM AUTHOR]

In this paper, the role of the El Niño-Southern Oscillation (ENSO), measured by the Equatorial Southern Oscillation Index (EQSOI), is used to formally forecast the inflation and GDP growth rates of the United States, advanced (excluding the United States) and emerging countries, as well as the world economy (barring the United States). We rely on univariate and multivariate singular spectrum analyses (SSA), as well as mixed-frequency version of the latter since the EQSOI is monthly, while GDP is available only at quarterly frequency unlike monthly inflation rates. We find statistically significant evidence of the ability of the EQSOI in forecasting inflation and GDP growth rates of the four economic blocs, though there are exceptions in terms of forecasting gains associated with inflation rate of emerging economies and the growth rate of the United States. Our results have important implications for policymakers. [ABSTRACT FROM AUTHOR]