K-means non-uniform-quantization digital-analog radio-over-fiber scheme for THz-band photonics-aided wireless fronthaul.

We propose a non-uniform-quantization digital-analog radio-over-fiber (NUQ-DA-RoF) scheme based on an advanced K-means NUQ algorithm and demonstrate it experimentally in a 2-m 300-GHz photonics-aided wireless fronthaul system. Results show that the NUQ-DA-RoF scheme achieves a SNR gain of ∼1.9 dB compared to the uniform-quantization DA-RoF (UQ-DA-RoF) at an equivalent Common Public Radio Interface equivalent data rate (CPRI-EDR). Remarkably, the NUQ-DA-RoF scheme exhibits an ∼1.6-dB power sensitivity enhancement over the UQ-DA-RoF at the 256-QAM SNR threshold. These findings highlight the advantages of the NUQ-DA-RoF scheme over UQ-DA-RoF in terms of power budget and SNR improvement, suggesting promising prospects for future radio access networks and wireless fronthaul.

Microfluidics identify moso bamboo and henon bamboo by leaf protoplast subpopulations with single-cell analysis.

Current techniques identifying herbal medicine species require marker labeling or lack systematical accuracy (expert authentication). There is an emerging interest in developing an accurate and label-free tool for herbal medicine authentication. Here, a high-resolution microfluidic-based method is developed for identifying herbal species by protoplast subpopulations. Moso bamboo and henon bamboo are used as a model to be differentiated based on protoplast. Their biophysical properties factors are characterized to be 7.09 (± 0.39) × 108 V/m2 and 6.54 (± 0.26) × 108 V/m2, respectively. Their biophysical distributions could be distinguished by the Cramér-von Mises criterion with a 94.60% confidence level. The subpopulations of each were compared with conventional flow cytometry indicating the existence of subpopulations and the differences between the two species. The subsets divided by a biophysical factor of 8.05(± 0.51) × 108 V/m2 suggest good consistency with flow cytometry. The work demonstrated the possibility of microfluidics manipulation on protoplast for medication safety use taking advantage of dielectrophoresis. The device is promising in developing a reliable and accurate way of identifying herbal species with difficulties in authentication.

The Chinese version of the general benefit finding scale (GBFS): Psychometric properties in a sample of college students.

BACKGROUND: Benefit finding has become a central construct in the evolution of positive psychology and attracted attention in recent literature. This study aimed to translate and validate the General Benefit Finding Scale (GBFS) in Chinese college students. METHODS: Forward- and back-translation of the GBFS was followed by the assessment of semantic equivalence and content validity. A sample of 589 college students was recruited in China to conduct reliability and validity analysis. The construct validity was assessed using exploratory (EFA) and confirmatory factor analysis (CFA). Concurrent validity was assessed using Pearson's correlation coefficients of the GBFS with the Perceived Stress Scale (PSS) and World Health Organization-Five Well-Being (WHO-5). Internal consistency and two-week test-retest reliability were also evaluated. RESULTS: The content validity index for each item ranged from 0.83 to 1.00. EFA revealed a six-factor model, which exhibited acceptable goodness of fit in CFA (standardized root mean square residual = 0.031, root mean square error of approximation = 0.059, goodness-of-fit index = 0.860, comparative fit index = 0.904, Tucker-Lewis index = 0.890, chi-squared/degree of freedom = 2.07). The concurrent validity of the GBFS was supported by its statistically significant correlations with PSS (r = -0.271, p<0.001) and WHO-5 (r = 0.354, p<0.001). Moreover, the internal consistency for the overall scale was satisfactory, with Cronbach's α coefficient of 0.93 and McDonald's omega reliability of 0.94. The test-retest reliability was 0.82. CONCLUSIONS: Although the Chinese version of GBFS was examined in a homogeneous convenience sample of college students, it provides a reliable and valid instrument for assessing benefit finding in the Chinese context.

Enantioselective Nickel-Electrocatalyzed Reductive Propargylic Carboxylation with CO2.

The exploitation of carbon dioxide (CO2) as a sustainable, plentiful, and harmless C1 source for the catalytic synthesis of enantioenriched carboxylic acids has long been acknowledged as a pivotal task in synthetic chemistry. Herein, we present a current-driven nickel-catalyzed reductive carboxylation reaction with CO2 fixation, facilitating the formation of C(sp3)-C(sp2) bonds by circumventing the handling of moisture-sensitive organometallic reagents. This electroreductive protocol serves as a practical platform, paving the way for the synthesis of enantioenriched propargylic carboxylic acids (up to 98% enantiomeric excess) from racemic propargylic carbonates and CO2. The efficacy of this transformation is exemplified by its successful utilization in the asymmetric total synthesis of (S)-arundic acid, (R)-PIA, (S)-chizhine D, (S)-cochlearin G, and (S,S)-alexidine, thereby underscoring the potential of asymmetric electrosynthesis to achieve complex molecular architectures sustainably.

Electrochemical-induced solvent-tuned selective C(sp3)-H bond activation towards the synthesis of C3-functionalized chromone derivatives.

An unprecedented solvent-tuned electrochemical method for selective C(sp3)-H bond activation towards the synthesis of C3 functionalized chromone derivatives has been developed. This electrosynthesis protocol provides an efficient and green way to access various C3-functionalized chromones by avoiding traditionally employed transition metals and high temperatures. The swappable chemoselectivity was controlled mainly by altering the solvent and the current. A plausible reaction mechanism has been proposed with the help of radical capture and cyclic voltammetry experiments.

Adaptively resettable microfluidic patch for sweat rate and electrolytes detection.

Skin-interfaced microfluidic patch has become a reliable device for sweat collection and analysis. However, the intractable problems of emptying the microchannel for reuse, and the channel's volumetric capacity limited by the size of the patch, directly hinder the practical application of sweat sensors. Herein, we report an adaptively resettable microfluidic sweat patch (Art-Sweat patch) capable of continuously monitoring both sweat rate (0.2-4.0 µL min-1) and total ionic charge concentration (10-200 mmol L-1). We develop a platform with a vertical and horizontal microchannel combined strategy, enabling repeatedly filling sweat and emptying the microchannel for autonomously resetting and detecting. The variation in the emptied volume is designed to be adaptively identified by the sensor, resulting in enhanced stability and an enlarged volumetric capacity of over 300 µL. By integrating with self-designed wireless transmission modules, the proposed Art-Sweat patch shows product-level wearability and high performance in monitoring variations in regional sweat rate and concentration for hydration status assessment.

Delta-sigma modulation supporting the 4194304QAM dual polarization signal at the W-band transmission over a 4.6†km wireless distance.

In this Letter, we propose a dual-polarized coherent millimeter-wave system based on differential delta-sigma modulation (D-DSM) intended for long-distance wireless transmission in the W-band. The proposed system can transmit polarization-division-multiplexed (PDM) D-DSM signals with modulation orders up to 4194304QAM over a wireless channel for 4.6 km at a signal baud rate of 20 G. After 4.6 km of wireless transmission, we successfully achieve a bit error rate (BER) lower than the hard-decision forward error correction (HD-FEC) of 3.8 × 10-3 for 34.51 Gbit/s PDM-524288QAM and a BER lower than the soft-decision forward error correction (SD-FEC) of 4.2 × 10-2 for 32.23 Gbit/s PDM-4194304QAM.

Electrochemical multicomponent [2+2+1] cascade cyclization of enaminones and primary amines towards the synthesis of 4-acylimidazoles.

An electrochemical multicomponent [2+2+1] cascade cyclization of enaminones and primary amines towards the synthesis of 4-acylimidazoles has been developed. In an undivided cell, enaminones and primary amines can smoothly participate in this reaction to provide a series of 1,2-disubstituted 4-acylimidazoles at room temperature. The reaction avoids the use of both transition-metal catalysts and oxidation reagents, which makes it more sustainable and renewable.

Subtypes of nursing students' volunteer motivation in COVID-19: a latent profile analysis.

BACKGROUND: One factor that influences nursing students' decision to engage in volunteer activities is volunteer motivation. It is important to understand the motivations of nursing students to volunteer. However, the majority of current studies have concentrated on the present level of nursing students' motivation to volunteer. OBJECTIVES: To identify subgroups of nursing students' volunteer motivation and its influential factors. METHODS: From January to February 2022, a cross-sectional online study was conducted, and 2569 nursing students from 10 provinces in China were recruited. Participants completed the General Information Questionnaire, Volunteer Functional Inventory (VFI), Perceived Stress Scale (PSS) and Perceived Social Support Scale (PSSS). We explore the categories and characteristics of volunteer motivation using latent profile analysis. Then, we determined factors that affect undergraduate nursing students' volunteer motivation using multinomial logistic regression. RESULTS: The volunteer motivation score of the nursing students was 77.65 (15.22). The study found that volunteer motivation could be divided into three categories: low-low protective volunteer motivation group (9.3%), general-high career values volunteer motivation group (37.5%), and high volunteer motivation group (53.2%). Perceived social support scale score, perceived stress scale score, gender, and grade significantly influenced the volunteer motivation of nursing students in different categories (both P < 0.05). Women were more likely to have higher motivation to volunteer than men, and fourth-year nursing students were more likely to be in general-high career values volunteer motivation group. CONCLUSIONS: The study highlights the significant heterogeneity in volunteer motivation among nursing students. Higher volunteer motivation was associated with higher perceived social support and lower perceived stress. In addition, gender and academic year were significant influencing factors. Nursing educators should develop targeted volunteer management plans based on the typological characteristics of the population to motivate nursing students to volunteer and promote the development of individual physical and mental health and social well-being. TRIAL REGISTRATION: The survey was approved by the Biomedical Ethics Committee of the Department of Medicine, Xi'an Jiaotong University (No. 2022-0006).

Toward Smart, Flexible, and Omnidirectional Self-Powered Photodetection by an All-Solution-Processed In2O3/Pbl2 Heterojunction.

Amorphous In2O3 film is emerging as a promising oxide semiconductor for next-generation electronics and optoelectronics owing to high mobility and wide band gap. However, the persistent photocurrent phenomenon and high carrier concentration in amorphous In2O3 film are challenging the photodetection performances, resulting in a long response time and low Ilight/Idark ratio. In this work, the In2O3/PbI2 heterojunction is constructed by an all-solution synthesis process to inhibit the persistent photocurrent phenomenon and large dark current. Benefiting from the built-in electric field at the heterojunction interface, the In2O3/PbI2 heterojunction photodetector exhibits excellent self-powered photodetection performances with an ultralow dark current of 10-12 A, a high Ilight/Idark ratio of 104, and fast response times of 0.6/0.6 ms. Furthermore, the entire solution synthesis process and amorphous characteristics enable the fabrication of an In2O3/PbI2 heterojunction photodetector on arbitrary substrates to realize specific functions. When configured onto the polyimide substrate, the In2O3/PbI2 heterojunction photodetector shows excellent mechanical flexibility, bending endurance, and photoresponse stability. When implanted onto the transparent substrate, the In2O3/PbI2 heterojunction photodetector exhibits an outstanding omnidirectional self-powdered photodetection performance and imaging capability. All results pave the way for an all-solution-processed amorphous In2O3 film in advanced high-performance photodetectors.

A "One Arrow Three Eagle" Strategy to Improve CM-272 Primed Bladder Cancer Immunotherapy.

Immunotherapy using an immune-checkpoint blockade has significantly improved its therapeutic effects. CM-272, which is a novel epigenetic inhibitor of G9a, induces immunogenic cell death (ICD) for recovering the sensitivity to anti-PD-1 antibodies; however, the efficacy of CM-272 is greatly limited by promoting the transcription activity of HIF-1α to form a hypoxic environment. Here, a Fe3+ -based nanoscale metal-organic framework (MIL-53) is used to load CM-272 (ultra-high loading rate of 56.4%) for realizing an MIL-53@CM-272 nanoplatform. After entering bladder cancer cells, Fe3+ not only promotes the decomposition of H2 O2 into O2 for O2 -compensated sonodynamic therapy but reduces the high level of glutathione in the tumor microenvironment (TME) for enhancing reactive oxygen species, including ferroptosis and apoptosis. MIL-53 carriers can be degraded in response to the TME, accelerating the release of CM-272, which helps achieve the maximum effectiveness in an O2 -sufficient TME by attenuating drug resistance. Furthermore, MIL-53@CM-272 enhances dendritic cell maturation and synergistically combines it with an anti-programmed cell death protein 1 antibody during the study of immune-related pathways in the transcriptomes of bladder cancer cells using RNA-seq. This study presents the first instance of amalgamating nanomedicine with CM-272, inducing apoptosis, ferroptosis, and ICD to achieve the "one arrow three eagle" effect.

Tunable Contacts of Bi2 O2 Se Nanosheets MSM Photodetectors by Metal-Assisted Transfer Approach for Self-Powered Near-Infrared Photodetection.

Owing to the Fermi pinning effect arose in the metal electrodes deposition process, metal-semiconductor contact is always independent on the work function, which challenges the next-generation optoelectronic devices. In this work, a metal-assisted transfer approach is developed to transfer Bi2 O2 Se nanosheets onto the pre-deposited metal electrodes, benefiting to the tunable metal-semiconductor contact. The success in Bi2 O2 Se nanosheets transfer is contributed to the stronger van der Waals adhesion of metal electrodes than that of growth substrates. With the pre-deposited asymmetric electrodes, the self-powered near-infrared photodetectors are realized, demonstrating low dark current of 0.04 pA, high Ilight /Idark ratio of 380, fast rise and decay times of 4 and 6 ms, respectively, under the illumination of 1310 nm laser. By pre-depositing the metal electrodes on polyimide and glass, high-performance flexible and omnidirectional self-powered near-infrared photodetectors are achieved successfully. This study opens up new opportunities for low-dimensional semiconductors in next-generation high-performance optoelectronic devices.

Silk Fibroin-Regulated Nanochannels for Flexible Hydrovoltaic Ion Sensing.

The evaporation-induced hydrovoltaic effect based on ion-selective nanochannels can theoretically be employed for high-performance ion sensing; yet, the indeterminate ion-sensing properties and the acquisition of high sensing performance are rarely explored. Herein, a controllable nanochannel regulation strategy for flexible hydrovoltaic devices with highly sensitive ion-sensing abilities is presented across a wide concentration range. By multiple dip-coating of silk fibroin (SF) on an electrospinning nylon-66 nanofiber (NNF) film, the surface polarity enhancement, the fibers size regulation with a precision of ≈25 nm, and the nanostructure firm binding are achieved simultaneously. The resultant flexible freestanding hydrovoltaic device exhibits an open circuit voltage up to 4.82 V in deionized water, a wide ion sensing range of 10-7 to 100 m, and ultrahigh sensitivity as high as 1.37 V dec-1, which is significantly higher than the sensitivity of the traditional solid-contact ion-selective electrodes (SC-ISEs). The fabricated flexible ion-sensitive hydrovoltaic device is successfully applied for wearable human sweat electrolyte sensing and for environmental trace-ion monitoring, thereby confirming the potential application of the hydrovoltaic effect for ion sensing.

Enantio- and Diastereodivergent N-Heterocyclic Carbene/Nickel Dual-Catalyzed Umpolung Propargylic Substitutions of Enals.

The creation of full stereoisomers of an organic compound comprising multiple contiguous stereocenters with simultaneous control over both relative and absolute configurations remains a significant challenge in synthetic chemistry. Using a cooperative catalysis strategy, we established an N-heterocyclic carbene/nickel-catalyzed enantio- and diastereodivergent propargylation reaction to access 3,3'-disubstituted oxindoles, enabling the incorporation of internal alkyne functionality and the introduction of a single quaternary or vicinal quaternary/tertiary stereogenic center. By selecting the appropriate combination of catalyst chirality, all four potential stereoisomers of α-quaternary propargylated oxindoles were synthesized in a predictable and precise way with remarkable yields, diastereoselectivities, and enantioselectivities from identical starting materials. The synthetic utility of this method was demonstrated in the concise asymmetric total synthesis of (-)-debromoflustramine B and (-)-C(ß-Me)-debromoflustramine B.

Lattice-mismatch-free construction of III-V/chalcogenide core-shell heterostructure nanowires.

Growing high-quality core-shell heterostructure nanowires is still challenging due to the lattice mismatch issue at the radial interface. Herein, a versatile strategy is exploited for the lattice-mismatch-free construction of III-V/chalcogenide core-shell heterostructure nanowires by simply utilizing the surfactant and amorphous natures of chalcogenide semiconductors. Specifically, a variety of III-V/chalcogenide core-shell heterostructure nanowires are successfully constructed with controlled shell thicknesses, compositions, and smooth surfaces. Due to the conformal properties of obtained heterostructure nanowires, the wavelength-dependent bi-directional photoresponse and visible light-assisted infrared photodetection are realized in the type-I GaSb/GeS core-shell heterostructure nanowires. Also, the enhanced infrared photodetection is found in the type-II InGaAs/GeS core-shell heterostructure nanowires compared with the pristine InGaAs nanowires, in which both responsivity and detectivity are improved by more than 2 orders of magnitude. Evidently, this work paves the way for the lattice-mismatch-free construction of core-shell heterostructure nanowires by chemical vapor deposition for next-generation high-performance nanowire optoelectronics.

Potassium status and the risk of type 2 diabetes, cardiovascular diseases, and mortality: a meta-analysis of prospective observational studies.

Epidemiological evidence on the association between potassium and cardiometabolic outcomes remains controversial. This study aimed to examine associations of dietary intake and blood and urinary levels of potassium with risk of type 2 diabetes, cardiovascular disease (CVD), and mortality. Relevant prospective studies were retrieved through a comprehensive search of four electronic databases up to July 1, 2023. Random-effects models were used to pool the study-specific relative risks (RRs) and 95% confidence intervals (CIs). Fifty-six studies were included in this meta-analysis. A higher intake of potassium was significantly associated with a 16% lower risk of CVD (RR: 0.84, 95% CI: 0.78-0.90). Similar inverse associations were also observed between potassium intake and mortality. Each 1.0 g/d increment in potassium intake was associated with a decreased risk of CVD (RR: 0.85, 95% CI: 0.80-0.91) and all-cause mortality (RR: 0.93, 95% CI: 0.88-0.99). For blood and urinary potassium levels, higher level of blood potassium increased the risk of all-cause mortality by 23% (RR: 1.23, 95% CI: 1.11-1.36). The association of blood potassium levels with mortality was nonlinear (Pnon-linearit<0.001). However, urinary potassium levels were inversely associated with the risk of all-cause mortality (RR: 0.84, 95% CI: 0.76-0.93). Our findings support the benefits of moderate potassium consumption for primary prevention of chronic diseases and premature death.

Effect of Alloying Elements on the Short-Range Orders and Atomic Diffusion Behavior of Liquid Al-9Si Cast Alloys.

To investigate the influence of alloying elements (Zn, Mg, and Cu) on the structural and dynamical properties of liquid Al-9Si alloy, we conducted ab initio molecular dynamics (AIMD) simulations. Our results indicate that the structure of Al-Si-M ternary alloys is determined with a combination of atomic radii and mixing enthalpy, while the dynamic properties are primarily influenced by electronic structure of the alloying elements. Specifically, the addition of Cu promotes the formation of Al-Cu short-range order (SRO), while Zn has a higher propensity for Zn-Zn SRO. The Al-Cu SRO in liquid alloy may serve as the precursor for the Al2Cu reinforcing phase in Al-Si-Cu alloys. Upon the addition of Mg, a greater number of relatively stable perfect and distorted icosahedral structures, as well as hcp and bcc ordered structures with lower energies, are observed. Additionally, the presence of Mg leads to a reduction in the atomic diffusion rates of Al and Si, while Cu and Zn exhibit complex diffusion behavior influenced by the presence of Si atoms.

The Predictive Value of Serum NT-proBNP on One-Year All-Cause Mortality in Geriatrics Hip Fracture: A Cohort Study.

Objective This study evaluated the association between N-terminal prohormone of brain natriuretic peptide (NT-proBNP) concentration and one-year mortality in geriatric patients with intertrochanteric and femoral neck fractures receiving the operative treatment. Methods Consecutive age ≥65 years patients with hip fractures were screened between January 2015 and September 2019. Demographic and clinical characteristics of the patients were collected. The multivariate logistic regression models were used to identify the association between preoperative NT-proBNP concentrations and mortality. All analyses were performed using EmpowerStats and the R software. Result One thousand two hundred nineteen patients were included in the study. The average age was 79.73±6.65 years (range 66-99 years). The mean NT-proBNP concentration was 616.09±1086.85 ng/L (median 313.40 ng/L, range 16.09-20123.00 ng/L). The follow-up was 35.39±15.09 months (median 35.78 months, range 0.10-80.14 months). One hundred and eleven (9.1%) patients died within one year. After adjusting for confounding factors, multivariate logistic regression models showed a curved association between preoperative NT-proBNP concentration and one-year mortality. When the NT-proBNP concentration was below 1099 ng/L, the mortality increased by 10% (OR=1.10, 95%CI: 1.03-1.17, P=0.0025) when NT-proBNP increased by 100 ng/L. When the NT-proBNP concentration was above 1099 ng/L, the mortality did not increase anymore when NT-proBNP increased (OR=1.00, 95%CI: 0.99-1.02, P=0. 7786). Thus, NT-proBNP was a valuable indicator to predict high one-year mortality in practice. Conclusion The NT-proBNP concentrations were nonlinearly associated with mortality in elderly hip fractures with a saturation effect, and NT-proBNP was a risk indicator of all-cause mortality. A well-designed controlled trial to show the role of mortality by decreasing the concentration of NT-proBNP is needed in the future.

An Amorphous Native Oxide Shell for High Bias-Stress Stability Nanowire Synaptic Transistor.

The inhomogeneous native oxide shells on the surfaces of III-V group semiconductors typically yield inferior and unstable electrical properties metrics, challenging the development of next-generation integrated circuits. Herein, the native GaOx shells are profitably utilized by a simple in-situ thermal annealing process to achieve high-performance GaSb nanowires (NWs) field-effect-transistors (FETs) with excellent bias-stress stability and synaptic behaviors. By an optimal annealing time of 5 min, the as-constructed GaSb NW FET demonstrates excellent stability with a minimal shift of transfer curve (ΔVth ≈ 0.54 V) under a 60 min gate bias, which is far more stable than that of pristine GaSb NW FET (ΔVth ≈ 8.2 V). When the high bias-stress stability NW FET is used as the chargeable-dielectric free synaptic transistor, the typical synaptic behaviors, such as short-term plasticity, long-term plasticity, spike-time-dependent plasticity, and reliable learning stability are demonstrated successfully through the voltage tests. The mobile oxygen ion in the native GaOx shell strongly offsets the trapping states and leads to enhanced bias-stress stability and charge retention capability for synaptic behaviors. This work provides a new way of utilizing the native oxide shell to realize stable FET for chargeable-dielectric free neuromorphic computing systems.

PDM-OFDM 1-bit DSM 1024QAM/4096QAM signals at W-band transmission over 4.6-km wireless distance.

In this Letter, we propose the application of delta-sigma modulation (DSM) higher-order quadrature amplitude modulation (QAM) technology in long-distance transmission of W-band wireless communication, and demonstrate, for the first time to the best of our knowledge, the wireless transmission of millimeter wave signals in the W-band based on 1-bit DSM quantization using polarization-division-multiplexed orthogonal frequency division multiplexing (PDM-OFDM) 1024QAM/4096QAM for 4.6 km. We successfully achieved a bit error rate (BER) of 40-Gbit/s PDM-OFDM 1024QAM and 48-Gbit/s PDM-OFDM 4096QAM after 4.6-km wireless transmission, both lower than the soft decision forward error correction (SD-FEC) of 4.2 × 10-2. To the best of our knowledge, this is the first time that up to 4096QAM signals have been quantized and transmitted based on 1-bit DSM in a 4.6-km-long distance W-band millimeter wave system.