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The photoelectric effect is not truly instantaneous but exhibits attosecond delays that can reveal complex molecular dynamics1–7. Sub-femtosecond-duration light pulses provide the requisite tools to resolve the dynamics of photoionization8–12. Accordingly, the past decade has produced a large volume of work on photoionization delays following single-photon absorption of an extreme ultraviolet photon. However, the measurement of time-resolved core-level photoionization remained out of reach. The required X-ray photon energies needed for core-level photoionization were not available with attosecond tabletop sources. Here we report measurements of the X-ray photoemission delay of core-level electrons, with unexpectedly large delays, ranging up to 700 as in NO near the oxygen K-shell threshold. These measurements exploit attosecond soft X-ray pulses from a free-electron laser to scan across the entire region near the K-shell threshold. Furthermore, we find that the delay spectrum is richly modulated, suggesting several contributions, including transient trapping of the photoelectron owing to shape resonances, collisions with the Auger–Meitner electron that is emitted in the rapid non-radiative relaxation of the molecule and multi-electron scattering effects. The results demonstrate how X-ray attosecond experiments, supported by comprehensive theoretical modelling, can unravel the complex correlated dynamics of core-level photoionization.

Identifying multiple rival reaction products and transient species formed during ultrafast photochemical reactions and determining their time-evolving relative populations are key steps toward understanding and predicting photochemical outcomes. Yet, most contemporary ultrafast studies struggle with clearly identifying and quantifying competing molecular structures/species among the emerging reaction products. Here, we show that mega-electronvolt ultrafast electron diffraction in combination with ab initiomolecular dynamics calculations offer a powerful route to determining time-resolvedpopulations of the various isomeric products formed after UV (266 nm) excitation of the five-membered heterocyclic molecule 2(5H)-thiophenone. This strategy provides experimental validation of the predicted high (∼50%) yield of an episulfide isomer containing a strained three-membered ring within ∼1 ps of photoexcitation and highlights the rapidity of interconversion between the rival highly vibrationally excited photoproducts in their ground electronic state.

The accuracy and stability of laser are influenced not only by external environmental factors but also by the laser internal structure, heat source, input source, etc., resulting in four-degree-of-freedom (4-DOF) laser disturbances. In this study, to reduce the laser disturbances and improve laser quality, a 4-DOF fast steering mirror (FSM) with double Porro prisms, which is driven by a voice coil motor (VCM), was designed for a laser compensation system. The 4-DOF FSM addressed the limitations of commercial laser compensation systems by achieving a shorter optical path length, reducing the number of components, and simplifying the setup of laser compensation systems at various positions. Furthermore, it enhanced the static and dynamic performance of a 4-DOF FSM proposed in a previous study. Finite element analysis was conducted to analyze both the electromagnetic structure and mechanical structure of the proposed 4-DOF FSM. Furthermore, a mathematical model was established for its motion dynamics, ensuring that its static and dynamic performance satisfied the conditions of compensating laser disturbances. Finally, a PID closed-loop control was established for the 4-DOF FSM laser compensation system. By comparing the differences before and after laser compensation using the 4-DOF FSM, the compensatory function of the 4-DOF laser compensation system was validated, achieving real-time compensation for laser disturbances.

Understanding the origin of electron–phonon coupling in lead halide perovskites is key to interpreting and leveraging their optical and electronic properties. Here we show that photoexcitation drives a reduction of the lead–halide–lead bond angles, a result of deformation potential coupling to low-energy optical phonons. We accomplish this by performing femtosecond-resolved, optical-pump–electron-diffraction-probe measurements to quantify the lattice reorganization occurring as a result of photoexcitation in nanocrystals of FAPbBr3. Our results indicate a stronger coupling in FAPbBr3than CsPbBr3. We attribute the enhanced coupling in FAPbBr3to its disordered crystal structure, which persists down to cryogenic temperatures. We find the reorganizations induced by each exciton in a multi-excitonic state constructively interfere, giving rise to a coupling strength that scales quadratically with the exciton number. This superlinear scaling induces phonon-mediated attractive interactions between excitations in lead halide perovskites.

Pump–probe experiments with subfemtosecond resolution are the key to understanding electronic dynamics in quantum systems. Here we demonstrate the generation and control of subfemtosecond pulse pairs from a two-colour X-ray free-electron laser. By measuring the delay between the two pulses with an angular streaking diagnostic, we characterize the group velocity of the X-ray free-electron laser and show control of the pulse delay down to 270 as. We confirm the application of this technique to a pump–probe measurement in core-ionized para-aminophenol. These results reveal the ability to perform pump–probe experiments with subfemtosecond resolution and atomic site specificity.

Intense attosecond X-ray pulses are key for ultrafast nonlinear spectroscopy and diffractive imaging. Here we demonstrate the generation of terawatt-scale isolated attosecond pulses with a two-stage cascaded X-ray free-electron laser. These pulses have a median energy in excess of 100 μJ in the soft X-ray region. The temporal profile is characterized with an angular streaking measurement, revealing a maximum peak power of 1.1 TW. Our data show an increase in the average peak power of attosecond X-ray pulses by one order of magnitude over previous reported results and provide strong evidence of soliton-like superradiant behaviour in the X-ray regime.

An efficient dehydrogenation catalyst is crucial for the application of ammonia borane (NH3BH3, AB) as a solid chemical hydrogen storage material. In this work, a kind of nitrogen-doped rice husk activated carbon (N-RHC) was prepared by roasting melamine and rice husk at high temperature under nitrogen atmosphere. With N-RHC as the support, the rice husk-based carbon supported ruthenium catalyst (Ru/N-RHC) was prepared through impregnation with the RuCl3solution and its catalytic performance in the hydrolysis of ammonia borane to produce hydrogen was investigated. The results indicate that the Ru/N-RHC catalyst with a Ru loading of 5% performs excellently in the hydrolysis of ammonia borane; the reaction turnover frequency (TOF) reaches 83.71 min−1and the apparent activation energy decreases from 88.9 to 64.9 kJ/mol under light irradiation. In addition, the hydrogen production rate is positively correlated with the content of ammonia borane and catalyst.

The aim of this study was to investigate the prevalence of nutritional risk and malnutrition through the Nutrition Risk Screening, Nutrition Status Assessment, and Nutrition Support Action (NRASA) protocol. A total of 325 140 patients were screened, and 59 122 adults (19.31%) and 9154 children (48.38%) were considered to be “at nutritional risk.” The prevalence of nutritional risk was 18.60% (306 220 patients) based on Nutritional Risk Screening 2002 (NRS2002), and 95.62% (2687 patients) by the Mini-Nutritional Assessment Short-Form (MNA-SF). Almost 67% of 23 805 adult patients were identified to be malnourished. The prevalence of malnutrition was 47.34% (6227 patients) based upon the Subjective Global Assessment (SGA), 69.86% (2687 patients) by the Mini-Nutritional Assessment (MNA) and 97.92% (7689 patients) by the Patient-Generated Subjective Global Assessment (PG-SGA). The NRASA protocol showed that the nutritional care process can be successfully implemented to confer adequate and timely nutritional therapy for malnourished patients.

Eicosapentaenoic acid (EPA) has been reported to play an anti‐inflammatory and antioxidative stress role in a series of human diseases, including major depressive disorder. However, its exact mechanism is still largely unknown. Mouse BV‐2 cells were treated with lipopolysaccharide (LPS) to induce an in vitro inflammatory cell model of depression. Cytotoxic effects were assessed with MTT and lactate dehydrigebase release assays. Cytokine mediators were elevated by western blot and enzyme‐linked immunosorbent assays. Autophagy‐relators were determined by immunofluorescence and western blot analyses. Interaction relationships among molecules were evaluated utilizing chromatin immunoprecipitation and dual luciferase assays. Methylated miR‐29a‐3p was detected via methylation‐specific polymerase chain reaction. EPA treatment at 60 μM had no cytotoxic effects on BV2 cells and significantly inhibited the LPS‐induced inflammatory response and NLRP3 inflammasome but activated autophagy, while all these effects were reversed by the autophagy inhibitor 3‐MA. Importantly, miR‐29a‐3p exhibited a role similar to that of EPA in LPS‐treated BV2 cells. Mechanistically, EPA treatment elevated miR‐29a‐3p by repressing its promoter methylation. MAPK8 was a direct target of miR‐29a‐3p. Inhibition of miR‐29a‐3p greatly diminished the regulatory roles mediated by EPA in LPS‐treated BV2 cells, while these roles were further impeded after MAPK8 silencing. To conclude, our data demonstrated that EPA treatment alleviated LPS‐induced NLRP3 inflammasomes by activating autophagy via regulation of miR‐29a‐3p/MAPK8 signaling, which further elucidates the potential antidepressant mechanism of EPA.

Blockchain is regarded as a mainstream technology by corporate leaders, who believe it will drive a new generation of business models. The trends of digital innovation have accelerated corporate blockchain technology adoptions, but when it comes to its applications, numerous barriers still exist that must be carefully addressed. In contrast to past decades, data gathering with the help of information technology has switched from being an expensive to an inexpensive process. It brings users sufficient messages, but also incurs the information overload problem. To combat this, a fusion framework integrated FRST-PSO and fuzzy DEMATEL is introduced herein. It assists users in identifying essential information and depicting the opaque relationships among criteria. The findings indicate that improvement priority, which runs in the order of regulatory environment, blockchain development talent, system integration, and function and reliability based on the magnitude of the impact, serves as a reference for the blockchain technology adoption to facilitate/solidify a firm's competitive edges.

This research presents the contribution of profitability and asset utilization to a firm's value generation from a financial market viewpoint via slack-based measure network data envelopment analysis (SBM-NDEA). Despite its superiority in performance measurement, SBM-NDEA has a limitation when confronted with new added datasets as it lacks predictive ability. To overcome this, the authors integrate twin support vector machine into it. A manager's attitude toward risks also plays an essential role in efficiency improvement and value generation, but numerical messages do not convey such information. Textual messages with elastic natures thus bring information beyond just numerical messages. To assist users in quantifying risk types, the authors introduced an advanced text analyzer to conjecture a manager's attitude toward each risk. The results show that the performance evaluation model with forecasting capability can shift the manager's role from monitoring the past to planning the future. This study also demonstrates that the model with textual information reaches superior forecasting performance.

Much effort has been devoted to the development of supramolecular hydrogels due to their broad applications and conveniently controllable properties. Here, we demonstrate a novel supramolecular host–guest hydrogel, which is constructed by the host γ-CD complexed with the guest 1-(4-carboxybenzyl)-4,4′-bipyridinium chloride (1+·Cl–) through the π···π interaction, hydrogen bonding, and host–guest interactions. The supramolecular hydrogel [1+@γ-CD]nexhibits reversible electron transfer photochromic behavior and photomodulable fluorescence. The excellent photochromic and fluorescence properties support the practical utility of the supramolecular hydrogel as a visual display and anti-counterfeiting material.

Aging involves tissue and cell potential dysfunction characterized by stem cell senescence and extracellular matrix microenvironment (ECM) alteration. Chondroitin sulfate (CS), found in the ECM of normal cells and tissues, aids in maintaining tissue homeostasis. Here, CS-derived biomaterial (CSDB) from sturgeon is extracted to investigate its antiaging effect in senescence-accelerated mouse prone-8 (SAMP8) mice and elucidate the underlying mechanism of its action. Although CSDB has been widely extracted from different sources and used as a scaffold, hydrogel, or drug carrier for the treatment of various pathological diseases, CSDB has not yet been used as a biomaterial for the amelioration of senescence and aging features. In this study, the extracted sturgeon CSDB showed a low molecular weight and comprised 59% 4-sulfated CS and 23% 6-sulfated CS. In an in vitrostudy, sturgeon CSDB promoted cell proliferation and reduced oxidative stress to inhibit stem cell senescence. In an ex vivostudy, after oral CSDB treatment of SAMP8 mice, the stem cells were extracted to analyze the p16Ink4a and p19Arf gene-related pathways, which were inhibited and then SIRT-1 gene expression was upregulated to reprogram stem cells from a senescence state for retarding aging. In an in vivostudy, CSDB also restored the aging-phenotype-related bone mineral density and skin morphology to prolong longevity. Thus, sturgeon CSDB may be useful for prolonging healthy longevity as an anti-aging drug.

Direct visualization of ultrafast coupling between charge carriers and lattice degrees of freedom in photoexcited semiconductors has remained a long-standing challenge and is critical for understanding the light-induced physical behaviour of materials under extreme non-equilibrium conditions. Here we obtain a direct visualization of the structural dynamics in monocrystalline 2D perovskites. We achieve this by monitoring the evolution of wavevector-resolved ultrafast electron diffraction intensity following above-bandgap high-density photoexcitation. Our analysis reveals a light-induced ultrafast reduction in antiferro-distortion resulting from a strong interaction between the electron–hole plasma and perovskite lattice, which induces an in-plane octahedra rotation towards a more symmetric phase. Correlated ultrafast spectroscopy performed at the same carrier density as ultrafast electron diffraction reveals that the creation of a dense electron–hole plasma triggers the relaxation of lattice distortion at shorter timescales by modulating the crystal cohesive energy. Finally, we show that the interaction between carrier gas and lattice can be altered by tailoring the rigidity of the 2D perovskite by choosing an appropriate organic spacer layer.

The formation of 1:1 and 2:1 inclusion complexes between the hosts cyclodextrins (α-, β-, and γ-CD) and the guest 1-(4-carboxybenzyl)-4-[2-(4-pyridyl)vinyl]pyridinium chloride (guest CPP+·Cl–) was demonstrated by NMR spectroscopy. The inclusion complexes CPP+@α-CD, CPP+@β-CD and CPP+@γ-CD2display photochromic properties from pale yellow to red in the solid state. The electron-spin resonance (ESR) spectroscopic data of the CPP+@γ-CD2suggest that the photochromic behavior arises from the generation of the free radicals. The CPP+@γ-CD2can be easily coated on the filter paper and used in erasable inkless printing and anticounterfeiting. Most importantly, the mixture of CPP+@γ-CD2and 1+@β-CD (an inclusion complex previously reported, whose color after irradiation was blue) also can be coated on the filter paper, and the color of printing on the filter paper is tunable by controlling the mass proportions of CPP+@γ-CD2and 1+@β-CD.

Sublethal concentrations of insecticides can affect the population dynamics of insects by inducing changes in their reproductive traits; however, the underlying molecular mechanisms remain unclear. In previous transcriptomic experiments, triazophos was found to promote SfTOR transcription. Therefore, in this study, two representative insecticides, thiamethoxam (inhibiting reproduction) and triazophos (stimulating reproduction), were selected to evaluate the transcription of the key genes involved in the target of rapamycin (TOR) and juvenile hormone (JH) pathways under stress in Sogatella furcifera. The results showed that thiamethoxam could significantly inhibit the transcription of SfRheb, SfTOR, SfS6K, and SfHMGR, whereas triazophos significantly promoted the transcription of SfRheb, SfTOR, SfS6K, SfHMGR, SfMet, and SfKr-h1. Moreover, RNA interference (RNAi) technology was used to target and silence TOR signaling pathway-related genes. The results showed that RNAi-mediated silencing of SfRheb, SfTOR, and SfS6K significantly inhibited ovarian development and fecundity. The transcription of JH signaling pathway-related genes (i.e., SfHMGR, SfFAMeT, SfMet, and SfKr-h1) and SfVg was significantly inhibited. However, the effects of SfRheb and SfTOR silencing on female reproduction were partially mitigated by the JH analog methoprene. These results indicate that the TOR signaling pathway can regulate the JH signaling pathway and SfVg transcription. In addition, insecticide stress can influence the transcription of TOR signaling pathway-related genes and transduction of stress signals via the JH signaling pathway, thereby affecting the transcription of SfVg and ultimately regulating reproduction in females.

OBJECTIVE -- To determine the efficacy of oolong tea for lowering plasma glucose in type 2 diabetic patients in Miaoli, Taiwan. RESEARCH DESIGN AND METHODS -- A total of 20 [...]

This article investigates the maximum spreading of ferrofluid droplets impacting on a hydrophobic surface under nonuniform magnetic fields. A generalized model for scaling the maximum spreading is developed. It is observed that, if the magnetic field strength is zero, a ferrofluid droplet not only demonstrates similar spreading dynamics as the water droplet but also obeys the same scaling law for the maximum spreading factor. Therefore, this article emphasizes the effects of magnetic field strength. In this regard, a dimensionless parameter (Nm) is introduced as the ratio between inertial force and Kelvin force, with an assumption that the kinetic energy mainly transforms to thermal energy. This parameter allows us to rescale all experimental data on a single curve with the Padé approximant, which is applicable to a wide range of impact velocities and magnetic field strengths.

Background: Colorectal cancer (CRC) is the fourth most prevalent cancer in the world. However, the molecular mechanism underlying CRC is largely unknown. Objective: To explore the pathogenic mechanism of CRC and to facilitate better diagnosis and treatment of this disease. Methods: Differentially expressed miRNAs (DEMs) and genes (DEGs) in CRC vs. Control samples from the miRNA expression data in GSE115513 and the miRNA and mRNA expression data in the TCGA-COAD dataset were screened, followed by the construction of the miRNAmRNA regulatory network. Functional and pathway enrichment analysis, protein-protein interaction (PPI) analysis, and survival analysis were then performed for these DEGs and DEMs. Results: We identified 64 DEMs from the GSE115513 dataset and 265 DEMs and 2218 DEGs from the TCGA-COAD dataset. miR-27a-3p was a hub DEM with the highest degree in the miRNA-mRNA network, while GRIN2B and PCDH10 were hub DEGs targeted by multiple miRNAs, including miR-27a-3p. SNAP25 and GRIN2B were also hub DEGs with the highest degree of interactions in the PPI network. These DEMs and DEGs were significantly enriched in multiple KEGG pathways, including proteoglycans expression and cAMP signaling pathway in cancer. Finally, seven DEGs, including FJX1 Dsc2, and hsa-miR-375, were revealed to be correlated with CRC prognosis. Conclusion: Aberrant expressions of genes and miRNAs were involved in the pathogenesis of CRC, probably by regulating proteoglycans expression and cAMP signaling. miR-27a-3p, PCDH10, GRIN2B, FJX1, Dsc2, and hsa-miR-375 were identified as potential targets for understanding the pathogenic mechanism of CRC. In addition, FJX1, Dsc2 and hsa-miR-375 were identified as potential predictive markers for CRC prognosis.

Water is one of the most important, yet least understood, liquids in nature. Many anomalous properties of liquid water originate from its well-connected hydrogen bond network1, including unusually efficient vibrational energy redistribution and relaxation2. An accurate description of the ultrafast vibrational motion of water molecules is essential for understanding the nature of hydrogen bonds and many solution-phase chemical reactions. Most existing knowledge of vibrational relaxation in water is built upon ultrafast spectroscopy experiments2–7. However, these experiments cannot directly resolve the motion of the atomic positions and require difficult translation of spectral dynamics into hydrogen bond dynamics. Here, we measure the ultrafast structural response to the excitation of the OH stretching vibration in liquid water with femtosecond temporal and atomic spatial resolution using liquid ultrafast electron scattering. We observed a transient hydrogen bond contraction of roughly 0.04 Å on a timescale of 80 femtoseconds, followed by a thermalization on a timescale of approximately 1 picosecond. Molecular dynamics simulations reveal the need to treat the distribution of the shared proton in the hydrogen bond quantum mechanically to capture the structural dynamics on femtosecond timescales. Our experiment and simulations unveil the intermolecular character of the water vibration preceding the relaxation of the OH stretch.

The effects of single-stage solution treatment (SST), enhanced solution treatment (EST), high-temperature pre-precipitation (HTPP) and multi-stage solution treatment (MST) on the microstructure, mechanical properties and corrosion resistance of the as-extruded 7055 aluminium alloy (AA7055) helical profile were investigated using differential scanning calorimetry (DSC), optical microscopy (OM), scanning electron microscopy (SEM), electron back-scattered diffraction (EBSD) and transmission electron microscopy (TEM). It was observed that EST and MST could promote the dissolution of the second-phase particles compared with the traditional SST, and the intergranular phases were distinctly discontinuously distributed after HTPP and MST. There was obvious difference in the main texture type and texture strength for the alloy after different solid solution treatments. HTPP could improve the corrosion resistance of the alloy by regulating the intergranular phases, but the mechanical properties were severely weakened. While the good corrosion resistance of the alloy could be obtained by MST without obvious strength loss. As a result, the MST is an ideal solid solution treatment scheme for AA7055.

The traditional optical flow method is based on the assumption of spatial consistency of the optical flow field. It is easy to reduce the tracking quality and even lead to the loss of target tracking in the areas of image feature missing, boundary and occlusion. A semi-dense optical flow method is proposed to realise stable tracking of image features. Firstly, the feature points are preserved by calculating the pixel points with large change of pixel gradient in the image; Secondly, according to the principle of grey level invariance, the grey level difference function between the corresponding feature points of adjacent frames is constructed; Finally, the gradient descent principle is used to optimise the grey difference function and realise the accurate matching of feature points of adjacent frames. The results show that compared with the traditional LK optical flow method, this algorithm can effectively improve the feature tracking capability, and at the same time can effectively retain the useful information in the image. Compared with the traditional feature point matching method, the algorithm presented in this paper has an efficient operation rate.

We employ few-femtosecond extreme ultraviolet (XUV) transient absorption spectroscopy to reveal simultaneously the intra- and interband carrier relaxation and the light-induced structural dynamics in nanoscale thin films of layered 2H-MoTe2semiconductor. By interrogating the valence electronic structure via localized Te 4d(39–46 eV) and Mo 4p(35–38 eV) core levels, the relaxation of the photoexcited hole distribution is directly observed in real time. We obtain hole thermalization and cooling times of 15 ± 5 fs and 380 ± 90 fs, respectively, and an electron–hole recombination time of 1.5 ± 0.1 ps. Furthermore, excitations of coherent out-of-plane A1g(5.1 THz) and in-plane E1g(3.7 THz) lattice vibrations are visualized through oscillations in the XUV absorption spectra. By comparison to Bethe–Salpeter equation simulations, the spectral changes are mapped to real-space excited-state displacements of the lattice along the dominant A1gcoordinate. By directly and simultaneously probing the excited carrier distribution dynamics and accompanying femtosecond lattice displacement in 2H-MoTe2within a single experiment, our work provides a benchmark for understanding the interplay between electronic and structural dynamics in photoexcited nanomaterials.

Using in situ electron diffraction techniques, we demonstrate that femtosecond optical excitation above a threshold fluence of the amorphous, as-deposited, phase change material Ge2Sb2Te5creates large, 100 μm scale single crystals. This is 2 orders of magnitude larger than previously reported grains synthesized via photoexcitation. Transmission electron microscopy shows that these large crystals are dewetted regions with a face-centered cubic structure. Energy-dispersive X-ray spectroscopy indicates that the crystals have the same composition as the initial amorphous phase. We present a theoretical model which shows that this arises from a crossover from a nucleation-dominated crystallization regime to a growth-dominated crystallization regime, and we show that the measured grain size is consistent with Johnson–Mehl–Avrami–Kolmogorov (JMAK) crystallization theory for temperatures near the melting temperature. The ability to grow macroscopic single crystals from an amorphous material, and on arbitrary amorphous substrates, opens up a large area of potential applications, as well as new opportunities for tuning the nucleation, growth, and switching characteristics of phase-change materials.

The inspection of Friedel’s law in ultrafast electron diffraction (UED) is important to gain a comprehensive understanding of material atomic structure and its dynamic response. Here, monoclinic gallium telluride (GaTe), as a low-symmetry, layered crystal in contrast to many other 2D materials, is investigated by mega-electronvolt UED. Strong out-of-phase oscillations of Bragg peak intensities are observed for Friedel pairs, which does not obey Friedel’s law. As evidenced by the preserved mirror symmetry and supported by both kinematic and dynamic scattering simulations, the intensity oscillations are provoked by the lowest-order longitudinal acoustic breathing phonon. Our results provide a generalized understanding of Friedel’s law in UED and demonstrate that by designed misalignment of surface normal and primitive lattice vectors, coherent lattice wobbling and effective shear strain can be generated in crystal films by laser pulse excitation, which is otherwise hard to achieve and can be further utilized to dynamically tune and switch material properties.

Study design: A pre-post observational study. Objectives: To evaluate the safety and feasibility of a new rehabilitation robotic device for assisting individuals with lower extremity motor complete lesions following spinal cord injury (SCI). Setting: Three hospitals in Sichuan Province, China. Methods: Individuals aged 15–75 years with an SCI between vertebrae six (T6) and lumbar 1 (L1) and complete motor paralysis participated in an exoskeletal-assisted walking (EAW) programme (2 weeks, 5 days/week, 30 min/day). Data were collected pre-, mid- (week 1) and post-intervention (week 2). Results: Twenty-eight individuals (mean age = 41.3, 71% males) participated in the EAW programme. The distance walked during the 6-min walking test (6MWT) increased relative to that at baseline, during week 1 (13.0 ± 5.3 m) and week 2 (16.2 ± 5.3 m) when wearing the exoskeleton. The walking speed during the 10-m walking test (10MWT) increased from 0.039 ± 0.016 to 0.045 ± 0.016 m/s. The Hoffer walking ability grade, the Spinal Cord Independence Measure (SCIM), and the Walking Index for SCI II (WISCI II) changed after 2 weeks of EAW. No improvement in lower extremity motor score (LEMS) was observed. The rates of adverse events and serious adverse events were 21% and 4%, respectively. Conclusions: The EAW programme with the new robotic exoskeleton provided potential meaningful improvements in mobility for individuals with SCI and had few adverse events.

Metal nanocrystals exhibit important optoelectronic and photocatalytic functionalities in response to light. These dynamic energy conversion processes have been commonly studied by transient optical probes to date, but an understanding of the atomistic response following photoexcitation has remained elusive. Here, we use femtosecond resolution electron diffraction to investigate transient lattice responses in optically excited colloidal gold nanocrystals, revealing the effects of nanocrystal size and surface ligands on the electron–phonon coupling and thermal relaxation dynamics. First, we uncover a strong size effect on the electron–phonon coupling, which arises from reduced dielectric screening at the nanocrystal surfaces and prevails independent of the optical excitation mechanism (i.e.,inter- and intraband). Second, we find that surface ligands act as a tuning parameter for hot carrier cooling. Particularly, gold nanocrystals with thiol-based ligands show significantly slower carrier cooling as compared to amine-based ligands under intraband optical excitation due to electronic coupling at the nanocrystal/ligand interfaces. Finally, we spatiotemporally resolve thermal transport and heat dissipation in photoexcited nanocrystal films by combining electron diffraction with stroboscopic elastic scattering microscopy. Taken together, we resolve the distinct thermal relaxation time scales ranging from 1 ps to 100 ns associated with the multiple interfaces through which heat flows at the nanoscale. Our findings provide insights into optimization of gold nanocrystals and their thin films for photocatalysis and thermoelectric applications.

The quantum-mechanical motion of electrons in molecules and solids occurs on the sub-femtosecond timescale. Consequently, the study of ultrafast electronic phenomena requires the generation of laser pulses shorter than 1 fs and of sufficient intensity to interact with their target with high probability. Probing these dynamics with atomic-site specificity requires the extension of sub-femtosecond pulses to the soft X-ray spectral region. Here, we report the generation of isolated soft X-ray attosecond pulses with an X-ray free-electron laser. Our source has a pulse energy that is millions of times larger than any other source of isolated attosecond pulses in the soft X-ray spectral region, with a peak power exceeding 100 GW. This unique combination of high intensity, high photon energy and short pulse duration enables the investigation of electron dynamics with X-ray nonlinear spectroscopy and single-particle imaging, unlocking a path towards a new era of attosecond science.

Multi-stimuli-responsive chromic materials have immense potential for utilization. Herein, two supramolecular inclusion complexes were prepared by self-assembly of β-cyclodextrin (β-CD) with dialkylcarboxyl-substituted viologens, N,N′-di(3-carboxy-propyl)-4,4′-bipyridinium dichloride (CPV·Cl2) and N,N′-di(6-carboxy-hexyl)-4,4′-bipyridinium dibromide (CHV·Br2). The self-assembled inclusion complexes CPV2+@β-CD and CHV2+@β-CD2in the solid-state exhibited naked-eye photochromism, thermochromism, and electrochromism in response to multiple external stimuli including light, temperature, and electric field, respectively. Solid-state UV–vis diffuse reflectance and electron spin resonance (ESR) spectroscopy revealed that the observed photochromism, thermochromism and electrochromism are attributed to the formation of viologen free radicals induced by electron transfer under external stimuli. The excellent stimuli-response chromic properties of the title inclusion complexes support their practical utility in visual display, multiple anticounterfeiting, and multilevel information encryption.

Two-dimensional transition metal dichalcogenides (TMDs) draw strong interest in materials science, with applications in optoelectronics and many other fields. Good performance requires high carrier concentrations and long lifetimes. However, high concentrations accelerate energy exchange between charged particles by Auger-type processes, especially in TMDs where many-body interactions are strong, thus facilitating carrier trapping. We report time-resolved optical pump-THz probe measurements of carrier lifetimes as a function of carrier density. Surprisingly, the lifetime reduction with increased density is very weak. It decreases only by 20% when we increase the pump fluence 100 times. This unexpected feature of the Auger process is rationalized by our time-domain ab initio simulations. The simulations show that phonon-driven trapping competes successfully with the Auger process. On the one hand, trap states are relatively close to band edges, and phonons accommodate efficiently the electronic energy during the trapping. On the other hand, trap states localize around defects, and the overlap of trapped and free carriers is small, decreasing carrier-carrier interactions. At low carrier densities, phonons provide the main charge trapping mechanism, decreasing carrier lifetimes compared to defect-free samples. At high carrier densities, phonons suppress Auger processes and lower the dependence of the trapping rate on carrier density. Our results provide theoretical insights into the diverse roles played by phonons and Auger processes in TMDs, and generate guidelines for defect engineering to improve device performance at high carrier densities.

Over the past decades, Taiwan has achieved remarkable goals in air pollution reduction with the concentrations of several common air pollutants such as CO, NOx, PM10, PM2.5, and SO2going down. In contrast to these achievements, the mitigation of O3remains extremely tough due to the complexity of its formation process involving synergistic effects of precursor reductions and meteorological influences. During the local COVID-19 crises in Taiwan and the Level 3 alert in 2021, air pollutants directly emitted from the traffic such as CO and NOxpresent clear relationships with the drop of the recorded freeway traffic volume due to the alert, while PM10and PM2.5which are also relevant to the traffic do not show indications of being greatly influenced by the decrease of the traffic flow. Although road traffic is not regarded as a main source of SO2by current understanding, the unusual SO2variation patterns found in this study suggest a prolonged impact for months from the changes of travel behavior during the epidemic. In contrast, the epidemic did not exert influences on industrial SO2concentration which accounts for a large portion of total SO2in Taiwan, and a similar scenario is also seen in each type of O3monitoring. Although some results discussed in this study are not in line with current consensuses and understandings in terms of the nation of certain air pollutants, these findings may disclose new perspectives which could be a potential benefit to air quality improvement projects in the future.

Table of Contents Abstract Introduction Methods Results Discussion Conclusion References Abstract Objective: Epidemiological research can assist with clinical practice and service planning, and can also help to generate hypotheses about [...]

The light-induced selective population of short-lived far-from-equilibrium vibration modes is a promising approach for controlling ultrafast and irreversible structural changes in functional nanomaterials. However, this requires a detailed understanding of the dynamics and evolution of these phonon modes and their coupling to the excited-state electronic structure. Here, we combine femtosecond mega-electronvolt electron diffraction experiments on a prototypical layered material, MoTe2, with non-adiabatic quantum molecular dynamics simulations and ab initioelectronic structure calculations to show how non-radiative energy relaxation pathways for excited electrons can be tuned by controlling the optical excitation energy. We show how the dominant intravalley and intervalley scattering mechanisms for hot and band-edge electrons leads to markedly different transient phonon populations evident in electron diffraction patterns. This understanding of how tuning optical excitations affect phonon populations and atomic motion is critical for efficiently controlling light-induced structural transitions of optoelectronic devices.

The deterioration in a corporation's profitability not only threatens its interests and sustainable development but also causes tremendous losses to other investors. Hence, constructing an effective pre-warning model for performance forecasting is an urgent requirement. Most previous studies only analyzed monetary-based ratios, but merely considering such ratios does not depict the full perspective of a corporation's business conditions. This study thus extends monetary-based ratios to non-monetary-based ratios and aggregates them through the analytic network process (ANP) with a risk-adjusted strategy to establish performance ranks of corporations. Analyzing a corporation's business relationships can help it to react to changes in the market and improve profit margins, as it draws upon such relationship networks for the transfer of scarce resources and knowledge. We believe that no current study adopts such a method to construct a forecasting model. To fill this gap in the literature, this study implements the social network (SN) technique to examine a corporation's competitive edge from seemingly noisy big media data, which are subsequently fed into an artificial intelligence (AI)-based technique to construct the model. The introduced model, examined through real-life cases under numerous conditions, offers a promising alternative for performance forecasting. [ABSTRACT FROM AUTHOR]

ObjectivePatient related clinical factors and intracranial aneurysms (IAs) at different locations may lead to statistical bias when investigating the rupture risk of IAs. Thus the purpose of this study was to identify the morphological parameters that are related to the rupture of mirror posterior communicating artery aneurysms (PComAAs).MethodsBetween August 2011 and July 2017, 68 patients with mirror PComAAs and aneurysmal subarachnoid hemorrhage were diagnosed by CT angiography at three medical centers. Morphological characteristics for PComAAs included bifurcation, shape, neck width, width, depth, maximum size, flow angle, parent vessel diameter, aspect ratio (AR), depth/width ratio, bottleneck factor, and size ratio (SR). Multiple logistic regression analysis was performed to determine the independent risk factors for rupture. Receiver operating characteristic curve analysis was performed to obtain the optimal thresholds.ResultsAR (OR 5.623) and SR (OR 5.570) were more commonly observed in the ruptured cohort. The threshold values of AR and SR were 0.98 and 1.21, respectively.ConclusionsMirror PComAAs are a useful model to investigate the rupture risk of PComAAs. AR (≥0.98) and SR (≥1.21) are better predictors of ruptured PComAAs.

Femtosecond carrier recombination in PbI2is measured using tabletop high-harmonic extreme ultraviolet (XUV) transient absorption spectroscopy and ultrafast electron diffraction. XUV absorption from 45 to 62 eV measures transitions from the iodine 4d core level to the conduction-band density of states. Photoexcitation at 400 nm creates separate and distinct transient absorption signals for holes and electrons, separated in energy by the 2.4 eV band gap of the semiconductor. The shape of the conduction band, and therefore the XUV absorption spectrum, is temperature-dependent, and nonradiative recombination converts the initial electronic excitation into thermal excitation within picoseconds. Ultrafast electron diffraction (UED) is used to measure the lattice temperature and confirm the recombination mechanism. The XUV and UED results support a second-order recombination model with a rate constant of 2.5 × 10–9cm3/s.

In ocean engineering, the applications are usually related to a free surface which brings so many interesting physical phenomena (e.g. water waves, impacts, splashing jets, etc.). To model these complex free surface flows is a tough and challenging task for most computational fluid dynamics (CFD) solvers which work in the Eulerian framework. As a Lagrangian and meshless method, smoothed particle hydrodynamics (SPH) offers a convenient tracking for different complex boundaries and a straightforward satisfaction for different boundary conditions. Therefore SPH is robust in modeling complex hydrodynamic problems characterized by free surface boundaries, multiphase interfaces or material discontinuities. Along with the rapid development of the SPH theory, related numerical techniques and high-performance computing technologies, SPH has not only attracted much attention in the academic community, but also gradually gained wide applications in industrial circles. This paper is dedicated to a review of the recent developments of SPH method and its typical applications in fluid-structure interactions in ocean engineering. Different numerical techniques for improving numerical accuracy, satisfying different boundary conditions, improving computational efficiency, suppressing pressure fluctuations and preventing the tensile instability, etc., are introduced. In the numerical results, various typical fluid-structure interaction problems or multiphase problems in ocean engineering are described, modeled and validated. The prospective developments of SPH in ocean engineering are also discussed.

Edible beans are among the most important grain legumes consumed by humans. To provide new information on the antioxidant phenolics of edible beans, the antioxidant capacity, total phenolic content (TPC), and total flavonoid content (TFC) in both soluble and bound fractions of 42 edible beans from China were systematically evaluated, with main phenolic compounds identified and quantified in 10 beans possessing the highest TPC. Edible beans contained a wide range of total antioxidant capacity and TPC generally comparable with common grains, fruits, and vegetables, and their bound fractions had significant antioxidant capacity, TPC, and TFC. Red sword bean was found for the first time to show extremely high total antioxidant capacity (ferrous[II] at 235 ± 13.2 µmol/g and Trolox at 164 ± 10.5 µmol/g) and TPC (1767 ± 58.3 mg of GAE/100 g). Phenolic compounds such as catechin, ferulic acid, gallic acid, p-coumaric acid, and protocatechuic acid were widely detected in selected beans. A positive correlation was found between antioxidant capacity (ferric-reducing antioxidant power [FRAP] and Trolox equivalent antioxidant capacity [TEAC] values) and TPC, with correlation coefficient r= 0.974 (FRAP value versus TPC) and r= 0.914 (TEAC value versus TPC). Therefore, beans with high antioxidant capacity and phenolic content can be valuable sources of dietary natural antioxidants for the prevention of oxidative stress-related chronic diseases.

Soil salinity affects the expression of serine/arginine-rich (SR) genes and isoforms by alternative splicing, which in turn regulates the adaptation of plants to stress. We previously identified the cassava SCL and SR subfamilies, belonging to the SR protein family, which are extensively involved in responses to abiotic stresses. However, the post-transcriptional regulatory mechanism of cassava RS subfamily in response to salt stress remains to be explored. In the current study, we identified 37 genes of the RS subfamily from 11 plant species and systematically investigated the transcript levels of the RS40and RS31genes under diverse abiotic stress conditions. Subsequently, an analysis of the conserved protein domains revealed that plant RS subfamily genes were likely to preserve their conserved molecular functions and played critical functional roles in responses to abiotic stresses. Importantly, we found that overexpression of MeRS40in Arabidopsisenhanced salt tolerance by maintaining reactive oxygen species homeostasis and up-regulating the salt-responsive genes. However, overexpression of MeRS40gene in cassava reduced salt tolerance due to the depression of its endogenous gene expression by negative autoregulation of its own pre-mRNA. Moreover, the MeRS40 protein interacted with MeU1-70Ks (MeU1-70Ka and MeU1-70Kb) in vivoand vitro, respectively. Therefore, our findings highlight the critical role of cassava SR proteins in responses to salt stress in plants.

MXenes have the potential for efficient light-to-heat conversion in photothermal applications. To effectively utilize MXenes in such applications, it is important to understand the underlying nonequilibrium processes, including electron–phonon and phonon–phonon couplings. Here, we use transient electron and X-ray diffraction to investigate the heating and cooling of photoexcited MXenes at femtosecond to nanosecond time scales. Our results show extremely strong electron–phonon coupling in Ti3C2-based MXenes, resulting in lattice heating within a few hundred femtoseconds. We also systematically study heat dissipation in MXenes with varying film thicknesses, chemical surface terminations, flake sizes, and annealing conditions. We find that the thermal boundary conductance (TBC) governs the thermal relaxation in films thinner than the optical penetration depth. We achieve a 2-fold enhancement of the TBC, reaching 20 MW m–2K–1, by controlling the flake size or chemical surface termination, which is promising for engineering heat dissipation in photothermal and thermoelectric applications of the MXenes.

Extreme ultraviolet (XUV) absorption spectra of thin-film samples using high-harmonic light sources show periodic artifacts that align with the peaks and valleys in the spectrum of the incident XUV beam. We show that a major source of this error is the interaction of spatial chirp in the XUV beam with thickness variations in the film. This concept is demonstrated using a patterned silicon nitride film as well as semiconductor and transition metal complex films. Numerical simulations using the measured spatial chirp and sample morphology reproduce the artifacts in heterogeneous films nearly quantitatively. We use these simulations to place limits on the sample quality required for detailed studies of the electronic structure of transition metal complexes at the M_2,3 edge. Finally, we show that artifacts can be created in transient absorption spectroscopy for even flat samples due to the inhomogeneous distribution of excited states created by a Gaussian pump beam. The experiments are carried out in a semi-infinite neon gas cell at a phase-matching condition that gives a broad harmonic continuum.

To assess postoperative rhinological complaints, length of hospital stay and complications related to endoscopic, endonasal trans-sphenoidal procedures.

A PCR-ELISA method for detecting the glyphosate resistant transgenic soybean was established and optimized. The results showed that the key parameters of PCR-ELISA were as follows: the concentration of digoxin tag probe was 0.5 µmol · L−1, the time of hybridization reaction was 15 min and the chromogenic reaction should last for 30 min. The sensitivity and the repeatability of our PCR-ELISA method were evaluated, and the results showed that it could be detected when the concentration of DNA template from transgenic soybean samples was 0.01% or higher, and the coefficient of variation of this method was less than 5% in our research condition. These results suggested that PCR-ELISA method establishment in this study had good repeatability and high precision for detecting the transgenic soybean samples.