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The objective of this study was to discriminate thyroid and parathyroid tissues using Raman spectroscopy combined with an improved support vector machine (SVM) algorithm. In thyroid surgery, there is a risk of inadvertently removing the parathyroid glands. At present, there is a lack of research on using Raman spectroscopy to discriminate parathyroid and thyroid tissues. In this article, samples were obtained from 43 individuals with thyroid and parathyroid tissues for Raman spectroscopy analysis. This study employed partial least squares (PLS) to reduce dimensions of data, and three optimization algorithms are used to improve the classification accuracy of SVM algorithm model in spectral analysis. The results show that PLS‐GA‐SVM algorithm has higher diagnostic accuracy and better reliability. The sensitivity of this algorithm is 94.67% and the accuracy is 94.44%. It can be concluded that Raman spectroscopy combined with the PLS‐GA‐SVM diagnostic algorithm has significant potential for discriminating thyroid and parathyroid tissues. [ABSTRACT FROM AUTHOR]

An improved model predictive control (MPC) with Luenberger state observer is proposed in this article for LC‐coupling hybrid active power filter (LC‐HAPF). Traditionally, the implementation of MPC for LC‐HAPF requires additional sensors to measure coupling capacitor voltage, thereby increases the system cost and reduces reliability. The existence of one‐step sampling delay in practice will also affect the final compensation performance. To relax these problems, both continuous and discrete models are deduced first. Then, the Luenberger observer is utilized based on the discrete model to mitigate the steady‐state error without additional sensors. In addition, the sampling delay compensation is provided by improving the prediction horizon. Finally, the effectiveness of the improved MPC for LC‐HAPF is verified by experiment results, indicating that the proposed method has fast dynamic response and low steady‐state error. [ABSTRACT FROM AUTHOR]

Micro-nano scale 3D printing is attracting attention as an alternative manufacturing method for a variety of applications in electronic information, biomedical, and sensing devices. Localized electrochemical deposition (LECD) based on nanopipettes is naturally superior and economical for the manufacturing of high-freedom, impurity-free metal conductors. However, flexible printing sacrifices roughness and straightness. Therefore, the present study initially establishes a simulation model for LECD and subsequently analyzes the key factors that influence the quality and stability of the deposited structure. Furthermore, an effective solution is proposed to enhance the surface quality. Second, a constant deposition current control method based on fuzzy proportional-intergral-derivaite (PID) is proposed to effectively suppress the fluctuation and improve the stability and quality of the deposited structure. Finally, compared with the open-loop control method, the proposed constant current control method can reduce the radial fluctuation of the copper pillar structure by 87%, and effectively improve the surface quality of the structure. The proposed method provides a new idea to carry out LCED-based 3D printing with high resolution at the micro-nano scale. [ABSTRACT FROM AUTHOR]

Accurately determining the solubility of ethane in oil‐based mud is crucial for assessing the severity of gas kicks and implementing appropriate well control procedures. The key factors influencing the solubility of ethane gas in oil‐based drilling fluids include the content of base oil, pressure, temperature, and the viscosity of the drilling fluid. This study aims to test the solubility of high‐purity ethane in oil‐based mud under simulated downhole conditions in a 5000 m deep well. The test covers a temperature range of 40–140°C and a partial pressure range of 0.17–5.92 MPa. The effects of temperature, pressure, base oil content, and drilling fluid viscosity on the solubility of ethane are analyzed using various experimental data processing methods. The results show that the variation in ethane solubility with pressure and temperature is nearly linear within the specified ranges. Furthermore, the impact of pressure (1.24–2.78%/MPa) on solubility is approximately 50 times greater than that of temperature (−0.013 to −0.049%/°C) in oil‐based drilling mud. Additionally, ethane's solubility decreases as the drilling fluid's viscosity increases. The ethane solubility in 80% and 90% oil‐based muds is roughly 1.6 times and 2.0 times higher than in 70% oil‐based mud under the same testing conditions. Models for predicting ethane solubility have been developed using screening procedures and statistical regression. These models can be incorporated into gas–liquid flow models to analyze flow behavior during gas kicks. [ABSTRACT FROM AUTHOR]

Background: The effective therapeutic approach is still an unmet need for patients diagnosed with both lung cancer and interstitial lung disease (ILD). This is primarily due to the possible risk of ILD exacerbation caused by surgery or radiotherapy. The current study aimed to investigate the efficacy and safety of local ablative therapy (LAT) for this specific population. Methods: Consecutive patients with non-small cell lung cancer (NSCLC) and ILD who received LAT between January 2018 and August 2022 were enrolled, and propensity score matching (PSM) was utilized to match the non-ILD group. The primary endpoint was recurrence-free survival (RFS), and secondary endpoints included overall survival (OS), adverse events (AEs) and hospital length of stay (HLOS). Results: The PSM algorithm yielded matched pairs in the ILD group (n = 25) and non-ILD group (n = 72) at a ratio of 1:3. There were no statistically significant differences in RFS (median 16.4 vs. 18 months; HR = 1.452, p = 0.259) and OS (median: not reached vs. 47.9 months; HR = 1.096, p = 0.884) between the two groups. Meanwhile, no acute exacerbation of ILD was observed in the ILD group. However, the incidence of pneumothorax, especially pneumothorax requiring chest tube drainage, was significantly higher (36.0% vs. 11.2%, p = 0.005) among patients with NSCLC and co-existing ILD, which resulted in longer HLOS (p = 0.045). Conclusion: Although ILD was associated with a higher incidence of pneumothorax, the efficacy of LAT for NSCLC patients with ILD was comparable to those without ILD, suggesting that LAT might be a reliable and effective treatment option for this population, particularly in the early stage. [ABSTRACT FROM AUTHOR]

The rapid advancement of human stem cell research and its expansion into emerging areas has resulted in an escalation of ethical challenges associated with these studies. As a result, there has been a corresponding increase in both the volume and complexity of institutional ethics reviews, coupled with higher expectations for the quality of the review process. In response to these challenges, this standard provides a comprehensive outline of the fundamental principles, content, types, and procedures of ethics review, specifically focusing on non-clinical human stem cell research. Its purpose is to provide clear operational and procedural guidelines, as well as recommendations, for the ethics review of such studies. The document was originally published by the Chinese Society for Cell Biology on August 30, 2022. It is our hope that the publication of these guidelines will facilitate the integration of ethical considerations and evaluations in a structured manner throughout the entire process of stem cell research, ultimately fostering a healthy and orderly development of the field. [ABSTRACT FROM AUTHOR]

'General requirements for the production of extracellular vesicles derived from human stem cells' is the first guideline for stem cells derived extracellular vesicles in China, jointly drafted and agreed upon by experts from the Chinese Society for Stem Cell Research. This standard specifies the general requirements, process requirements, packaging and labelling requirements and storage requirements for preparing extracellular vesicles derived from human stem cells, which is applicable to the research and production of extracellular vesicles derived from stem cells. It was originally released by the China Society for Cell Biology on 30 August 2022. We hope that the publication of this guideline will promote institutional establishment, acceptance and execution of proper protocols, and accelerate the international standardisation of extracellular vesicles derived from human stem cells. [ABSTRACT FROM AUTHOR]

In this paper, an open‐circuit fault‐tolerant topology of LC‐coupling hybrid active power filter (LC‐HAPF) and its control strategy are proposed at the switch level, which can greatly improve the reliability of the system. The proposed structure has a contactor between the midpoint of each bridge arm and the negative bus of the dc‐link capacitor. When a single‐phase fault occurs, the proposed LC‐HAPF can be reconstructed into a three‐phase four‐switch system to compensate for the harmonic and reactive power, while the power quality compensation effect is hardly affected. When a two‐phase fault occurs, the operation of the normal bridge arm is not affected, and the two faulty bridge arms can suppress harmonic current and compensate for a fixed reactive power through the passive filters. When the bridge arms all fail, the whole device acts as a passive filter to suppress the harmonic current of the load and to compensate for reactive power as well. Finally, the effectiveness of the proposed topology and its control strategy is verified by simulation and experiment results. In this paper, an open‐circuit fault‐tolerant topology of LC‐coupling hybrid active power filter (LC‐HAPF) and its control strategy are proposed at the switch level, which can greatly improve the reliability of the system. The proposed structure has a contactor between the midpoint of each bridge arm and the negative bus of the dc‐link capacitor. [ABSTRACT FROM AUTHOR]

Axially chiral N-arylindoles bearing a stereogenic C-N axis are unique important scaffolds in natural products, advance materials, pharmaceuticals and privileged chiral ligands or catalysts. Herein, we report the direct synthesis of C-N axially chiral N-arylindoles through a Pd-catalyzed free amine-directed atroposelective C-H olefination enabled by a spiro phosphoric acid (SPA) ligand. A wide range of enantioenriched N-aromatic amine indoles were obtained in high yields with good enantioselectivities (35 examples, up to 91% yield and up to 96% ee). The chiral products with free amine group offer an effective functional handle for down-stream diversity-oriented synthesis. [ABSTRACT FROM AUTHOR]

Background: Isolated congenital bilateral absence of vas deferens (iCBAVD) in men results in obstructive azoospermia and is mainly caused by pathogenic variants in cystic fibrosis transmembrane conductance regulator (CFTR) or adhesion G protein‐coupled receptor G2 (ADGRG2). Methods: The next‐generation sequencing (NGS) was used to screen the mutations in the proband, and Sanger sequencings were performed to validate the compound heterozygous variant of CFTR in his family members. Protein structure simulation was performed to discover the potential pathological mechanism. Results: This study reported novel compound heterozygous CFTR mutations (NM:000492.4, Intron: 5T; c.3965_3969dupTTGGG: p.R1325Gfs*5) in two brothers with obstructive azoospermia. The compound heterozygous CFTR mutations were first screened out by NGS in an infertile male patient who exhibited iCBAVD from a nonconsanguineous Chinese family. Histological analysis of the testicular biopsy from this patient revealed normal spermatogenesis and mature spermatozoa were observed in the seminiferous tubules. Surprisingly, the same compound heterozygous CFTR mutations were also observed in his brothers who also exhibited iCBAVD, with their parents being a heterozygous carrier for the mutations, as verified by Sanger sequencing. Protein structure simulation revealed that these mutations potentially led to impaired ATP‐binding ability of CFTR. Conclusion: We identified novel compound heterozygous CFTR mutations in two brothers and summarized the literature regarding CFTR mutation and male infertility. Our study may contribute to the genetic diagnosis of iCBAVD and future genetic counseling. [ABSTRACT FROM AUTHOR]

Breast cancer with bone metastasis accounts for serious cancer-associated pain which significantly reduces the quality of life of affected patients and promotes cancer progression. However, effective treatment using nanomedicine remains a formidable challenge owing to poor drug delivery efficiency to multiple cancer lesions and inappropriate management of cancer-associated pain. In this study, using engineered macrophage membrane (EMM) and drugs loaded nanoparticle, we constructed a biomimetic nanoplatform (EMM@DJHAD) for the concurrent therapy of bone metastatic breast cancer and associated pain. Tumor tropism inherited from EMM provided the targeting ability for both primary and metastatic lesions. Subsequently, the synergistic combination of decitabine and JTC801 boosted the lytic and inflammatory responses accompanied by a tumoricidal effect, which transformed the tumor into an ideal decoy for EMM, resulting in prolonged troop migration toward tumors. EMM@DJHAD exerted significant effects on tumor suppression and a pronounced analgesic effect by inhibiting μ-opioid receptors in bonemetastasismousemodels.Moreover, the nanoplatformsignificantly reduced the severe toxicity induced by chemotherapy agents. Overall, this biomimetic nanoplatform with good biocompatibility may be used for the effective treatment of breast cancer with bone metastasis. [ABSTRACT FROM AUTHOR]

The number of layers of 2D materials is of great significance for regulating the performance of nanoelectronic devices and optoelectronic devices, where the optimal thickness of the target sample should be determined before further physical research or device manufacturing steps. At present, a variety of different optical technologies have been proposed to determine the thickness of samples by using the relationship between the number of layers and optical properties, including optical contrast, optical imaging, Raman spectra, photoluminescence spectra, nonlinear spectra, near-field optical imaging, ellipsometry spectra, and hyperspectral imaging. In the past decade, the rapidly growing number of 2D materials and their heterostructures has exceeded the capacity of traditional experimental and computational methods. In recent years, machine learning (ML) is emerging as a powerful tool to support such traditional methods, which brings new opportunities to tap the potential of optical technology in a more perspicacious way. The application of optical technology has greatly facilitated the acquisition of optical information of materials, while ML algorithms provide a fast, high-throughput, and intelligent way to complete back-end data processing and inference. A profound integration of conventional optical technologies and ML algorithms significantly helps 2D materials progress in basic studies and practical applications and further promotes industrial manufacturing. [ABSTRACT FROM AUTHOR]

The development of a noble-metal-free cocatalyst is of great significance for boosting photocatalytic H2 evolution performance. Herein, SnSe2 is developed as a cocatalyst to in situ attachment on the surface of sulfur defect rich ZnIn2S4 (Vs-ZIS) via a simple hydrothermal method. Owing to the intimate atomic-level interface and the different work function between Vs-ZIS and SnSe2, a particular Ohmic junction with internal electric field is formed in Vs-ZIS/SnSe2, which facilitates the electrons in Vs-ZIS transfer to SnSe2 and participate in H2 evolution reaction rapidly. Moreover, the abundant S vacancies also benefit the separation of photocarriers in Vs-ZIS/SnSe2. The optimized Vs-ZIS/SnSe2 photocatalyst performs a high H2 evolution rate of 29.34mmol h-1 g-1 under visible light (p >420 nm) and an apparent quantum efficiency of 12.25% at 420 nm. Herein, constructive model on developing effective cocatalyst is afforded, and expediting photocarriers transfer through interfacial modulating. [ABSTRACT FROM AUTHOR]

In this article, a constant false alarm rate (CFAR) detection algorithm based on the fractional Fourier transform (FRFT) and orthogonal projection (OP) is proposed. With a low signal‐to‐clutter ratio (SCR), the radar returns of sea‐surface small targets are often submerged by sea clutter. The FRFT can accumulate target energy in the optimal order. Meanwhile, the OP suppresses the sea clutter in a projection space in the FRFT domain, thus enhancing the output SCR. The FRFT and the OP are in conjunction with the CFAR to realise target detection, which is referred to as the FRFT‐OP‐CFAR. For the FRFT‐OP‐CFAR detector, the most important is the selection of the optimal order p $p$ and the calculation of the OP operator ψx⊥ ${\boldsymbol{\psi }}_{x}^{\perp }$. The experimental results show that the proposed FRFT‐OP‐CFAR has a better clutter suppression and detection performance than some detectors in the authors' comparison. [ABSTRACT FROM AUTHOR]

Rare-earth (RE) ion doped crystalline materials have a wide spectrum of applications in lasers, amplifiers, sensors, as well as classical and quantum information processing. The incorporation of RE ions into integrated photonics holds great promise for enriching the designer’s toolbox with a view to addressing key performance features not available in existing photonic integration platforms. RE-ion-doped thin-film LiNbO3 (also called RE-ion-doped lithium-niobate-on-insulator, RE:LNOI), which inherits nearly all the material advantages as well as nanophotonic integration from the LNOI technology, meets the urgent demands for chip-integrated laser sources, optical amplifiers, and quantum memories based on LNOI photonics. In this article, a timely review is provided on the development of RE:LNOI photonics in terms of ion-doping techniques, chip-integrated lasers, and amplifiers, as well as low-temperature optical characterizations for quantum photonics. To conclude, some well-noted topics that may shape the future directions in lithium–niobate integrated photonics are discussed. [ABSTRACT FROM AUTHOR]

With the increasing development of integrated energy systems and the continuous promotion of integrated demand response (IDR) research, residential users with a large amount of demand response resources are drawing more and more widespread attention. In order to fully exploit the IDR potential of residential users and analyse the influence of user comfort and consumer psychology (UCCP) on IDR, the optimised operation study of load aggregator (LA) based on UCCP-IDR model is proposed. Firstly, a selforganising map algorithm for clustering is introduced, from which various types of users with differentiated consumption psychology are obtained. Secondly, user comfort and consumption psychology are taken into account to establish a user curtailable, shiftable and transformable load model. Thirdly, the user IDR optimisation model is established based on the load model considering the user response uncertainty. Finally, based on the optimisation strategy of user IDR, the total energy demand of LA is obtained, and thus the optimal operation model of LA equipment is established. The analysis shows that the proposed strategy can provide a more reliable and targeted integrated demand response strategy for residential users, and achieve a win--win situation for both LA and residential users. [ABSTRACT FROM AUTHOR]

Background: Primary cutaneous amyloidosis (PCA) is apruritic and potentially disfiguring disorder; this disease is usually diagnosed clinically due to its common occurrence. However, for cases with atypical presentations or for those physicians not familiar with PCA, the diagnosis can be a challenge. Objective: To observe the characteristics of PCA under dermoscopy and reflectance confocal microscopy (RCM) in order to gain experience and reference for clinicians to facilitate diagnosis. Methods: The typical lesions of 110 patients with primary cutaneous amyloidosis were observed by dermoscopy and RCM, and scanning results were recorded. Thirty patients followed by complete excision for histopathological analysis. Results: A total of 110 patients with clinically diagnosed PCA were enrolled. Forty‐seven patients had lesions consistent with macular amyloidosis and 63 with lichen amyloidosus. The dermoscopic findings of PCA shared a common feature, each 'macule' was composed of a central hub pattern surrounded by brownish pigmentation, The pattern of the central hub could be brown, white, scar‐like and structureless area. RCM features of total patients consisted of dermal papilla present cloud‐like agglomerate which are high refractive index. Conclusions: Dermoscopy and reflectance confocal microscopy can be used in the diagnosis of PCA, which can provide a basis for doctors to diagnose. [ABSTRACT FROM AUTHOR]

Bud development influences shoot branching and the plasticity and adaptability of plants. To explore the differences of post-embryonic development of different types of buds, shoots originated from adventitious buds and axillary buds of cuttings in two populations of balsam poplar (Populus balsamifera L.) were investigated for differences in leaf morphology, photosynthetic and growth characteristics, and the effects of a carbonic anhydrase (CA) inhibitor on CA activity, photosynthesis and mesophyll conductance (gm). The results showed that axillary buds produced ovate first few leaves and longer shoots while adventitious buds produced lanceolate first few leaves with higher specific leaf area (SLA). There were no significant differences in leaf area-based photosynthetic rate (An), maximum carboxylation rate (Vcmax), and maximum electron transport rate (Jmax) between shoots originated from the two bud types. Based on the principal component analysis, shoots of adventitious bud origin grouped on daytime respiration and SLA, while cuttings from axillary buds clustered toward the opposite direction of quantum yield and light saturation point. Shoots originated from different types of buds had different growth rates and biomass, but the direction of the differences varied with the population of the mother tree. The two populations differed in An, gm, and relationships between CA, An, and gm. There were differences in post-embryonic growth traits of shoots from axillary buds and those from adventitious buds, which may be an adaptive strategy for regeneration under different light conditions. [ABSTRACT FROM AUTHOR]

Background: To investigate the roles of the lysyl oxidase-like 1 (loxl1) gene in zebrafish eye development and the potency of loxl1 deficiency in mimicking the ocular manifestations of exfoliation syndrome (XFS). Methods: CRISPR/Cas9 technology was used to generate a frameshift coding deletion in zebrafish loxl1. Expression profiles and ocular manifestations of the wildtype, heterozygous mutant (loxl1+/-) and homozygous mutant (loxl1-/-) zebrafish were analysed in a range of developmental stages from zebrafish larvae to dissected adult zebrafish eyes. Results: The loxl1 deficiency caused zonular bundling disorders in juvenile zebrafish and accumulation of pearl-like particles adhering to the adult zebrafish zonule. The bundles appeared to lack form and were thinner in both loxl1+/- and loxl1-/- zebrafish compared with the wildtype (p < 0.01 for all Bonferroni post-hoc analyses). The zonule of loxl1-/- zebrafish appeared stretched, ragged and torn, with isolated fibres also detected. The particles in loxl1-/- zebrafish were more numerous (counts: 92.33 ± 10.02/100 µm2 vs. 58.33 ± 5.03/100 µm2, p = 0.006), but smaller in size (diameter: 0.21 ± 0.03 µm vs. 0.43 ± 0.04 µm, p = 0.002) compared with those in loxl1+/-. Transmission electron microscopy revealed thinning or even loss of elastic lamina in loxl1+/- Bruch's membrane (BM) (thickness of elastic lamina: 92.94 ± 18.19 nm in the wildtype vs 35.65 ± 14.76 nm in loxl1+/-, p = 0.003). The breakage of BM was observed in loxl1-/-. Conclusions: The loxl1-/- zebrafish is a promising animal model of XFS zonular pathology. [ABSTRACT FROM AUTHOR]

Ocean thermal energy has attracted much attention for its huge potential resources. It's proved that an ocean thermal energy conversion (OTEC) cycle system using ammonia ejectors is beneficial to improve the cycle efficiency. Thus, the performance of an ammonia ejector is studied numerically in this paper. Effects of working conditions which occurred inside the ammonia ejector, like primary flow pressure (1.3-2.1 MPa), secondary flow pressure (0.45-0.65 MPa), and back pressure (0.5-1.05 MPa), on the mixing process and flow phenomenon, are discussed in detail. The results demonstrate that the entrainment ratio of ammonia ejector ranging from 0.35-0.65 increases with decreasing primary flow pressure at the critical working mode, while the reverse is true for the critical back pressure. Two small vortexes are formed near the ejector wall due to the boundary layer separation when the ejector works at the subcritical or critical mode. These vortexes reduce the effective area and flow rate of the secondary flow. The Ma contours are nearly the same in the nozzle and mixing zone for the critical and subcritical mode, but distributions of Ma vary dramatically in the diffuser corresponding to the variation of secondary series of oblique shock. [ABSTRACT FROM AUTHOR]

The performance of praseodymium-doped indium gallium oxide (PrIGO) as the channel layer of thin-film transistors (TFTs) is widely investigated. The TFTs with Pr doping exhibit a remarkable suppression of the light-induced instability including a negligible photoresponse and significant enhancement in negative gate bias stress under illumination (NBITS). The structure, chemical composition, and oxygen vacancy concentration of PrIGO films are analyzed by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS), respectively. In addition, the low-frequency noise test is introduced to analyze the variation of trap density with Pr doping. The results indicate that the trap states induced by Pr doping facilitate the capture of free electrons by positively charged oxygen vacancies under illumination, which leads to the suppression of photoinduced carriers in the conduction band. [ABSTRACT FROM AUTHOR]

The fermented feed has been identified as a potential alternative to antibiotics in feeds that markedly affects gut health and growth performance of pigs. Two recent studies performed in our laboratory investigated that the fermented corn-soybean meal (fermented feed, FF) improved the gut health of pigs. This study was conducted to determine the effect of a FF on the carcass, meat quality, muscle fatty acids profile, muscle amino acid and antioxidant ability of grower-finisher pigs. In this study, a total of 48 crossbred barrows (Duroc × Landrace × Large White) were randomly divided into 2 treatments with unfermented corn-soybean diet (Ctrl) and FF diet. Compared with control pigs fed a standard diet, the results showed that FF significantly increased the muscle colour of redness and significantly reduced muscle moisture loss rate. Furthermore, FF significantly increased the content of aromatic amino acids such as aspartic acid, glutamic acid and alanine. More importantly, FF increased monounsaturated fatty acid and polyunsaturated fatty acid content. Collectively, FF could be a promising feed strategy in improving meat quality and nutritional value in grower-finisher pig. [ABSTRACT FROM AUTHOR]

An efficient Lewis base catalytic protocol to biologically important trifluoromethylated pyrazolines and pyrazoles is developed through triazene-heterocyclic alkene cycloaddition reactions of an array of oxa-/aza-benzonorbornadienes and coumarins with CF3CHN2. This triazene-heterobicyclic alkene cycloaddition procedure features good functional group tolerance, scaffold diversity, and feasible late-stage functionalization of some representative natural products. [ABSTRACT FROM AUTHOR]

C-N bond formation is crucial for the preparation of synthetic organic nitrogen-containing heterocyclic compounds. This work provides a facile and highly efficient strategy (ca. ∼92%) for the synthesis of quinazoline compounds, which involves tandem C-H/N-H bond functionalization using metal-free conditions without the need for an external oxidant. Meanwhile, the reaction system exhibits good functional group tolerance and a wide substrate scope. Furthermore, our corresponding isotope tracking experiments have shown that dimethyl sulfoxide acts as a carbon source. Finally, this work affords a new strategy toward the further design and synthesis of heteroaromatic rings. [ABSTRACT FROM AUTHOR]

Porcine pancreas lipase (PPL) was immobilized on magnetic multiwalled carbon nanotubes successfully for the synthesis of substituted 2H-chromenes. The catalytic activity of immobilized PPL was much higher than that of free PPL. Effects of reaction medium, temperature, and enzyme dosage were also investigated. Under optimum reaction conditions (acetylacetone (1 mmol), salicylaldehyde (1 equivalent), methanol (10 equivalent), and immobilized PPL (protein content: 30 mg; 65 °C; DMF 5 mL; 5 H), the immobilized PPL showed an excellent catalytic performance on the synthesis of substituted 2H-chromenes. Moreover, the immobilized PPL exhibited satisfactory thermostability, operational simplicity, and reusability in this reaction. [ABSTRACT FROM AUTHOR]

Protein crosslinks occur endogenously such as modifications by ubiquitinlike proteins for signaling, or exogenously through genetically encoded chemical crosslinkers (GECX) for studying elusive protein-protein interactions. However, it remains challenging to identify these protein crosslinks efficiently at the proteomic scale. Herein, software OpenUaa is developed for identifying protein crosslinks generated by genetically encoded unnatural amino acids and endogenous protein conjugation. OpenUaa features inclusive and open search capability, dramatically improving identification sensitivity and coverage. Integrating GECX with OpenUaa, the direct interactome of thioredoxin is identified in Escherichia coli cells, yielding 289 crosslinked peptides and corresponding to 205 direct binding protein of thioredoxin. These identified direct binders provide evidence for thioredoxin's regulation of redox state and mitochondria energy metabolism. When identifying endogenous conjugation of small ubiqtin-like modifier (SUMO), OpenUaa also markedly improves coverage of SUMOylated peptides by ?92%, revealing new SUMO targets. GECX-OpenUaa will enable efficient identification of direct interactomes of various proteins in live cells. [ABSTRACT FROM AUTHOR]

Thrust testing units with a piezoelectric dynamometer have unique traits such as excessive stiffness, tremendous measurement accuracy, dynamic performance and no hysteresis. These are widely used in the applications requiring force/thrust measurements in the aerospace industry and high‐end tool condition monitoring. The performance of these units is necessary to be evaluated. In this study, an improved layout of six‐degree of freedom force/thrust measurement stand is proposed and analysed theoretically and experimentally. The measurement stand is a structural component to measure six components of force, such as axial force/thrust (FX, FY, and FZ) and other components (MX, MY, and MZ). Test stand consists of seven piezoelectric sensors in two sections. The front part consists of four piezoelectric force sensors, while the rear part consists of three sensors. The rear section is hexagonal, with three sensors mounted at 120°. The measurement stand can measure the principal force/thrust up to 50,000 N. A mathematical model is derived for every sensor against forces in all directions. To calibrate the stand, a calibration platform is designed and fabricated. The calibration platform can generate a range of forces/moments. Calibration experiments verifies that the measurement stand is fairly functional to measure variety of forces/moments with high repeatability. [ABSTRACT FROM AUTHOR]

This study presents an analysis method of harmonic interaction characteristics between direct-drive wind turbines (DDWTs) based on αβ coordinates and the relative gain array (RGA). First, considering the digital delay of inverters, the capacitive current feedback active damping is applied to suppress the resonance of LCL filter, and the output current of DDWT is regulated by quasi-proportional resonant controller in the αβ coordinates and then combined with the topology of the directdrive wind farm (DDWF), the transfer function matrix of the DDWF is established. Second, based on the RGA principle, the relationship between parameters and harmonic interaction characteristics is quantitatively analysed. The results show that with the proportional coefficient increasing, the degree of negative interaction between DDWTs is strengthened, which increases the harmonic content in the negative interaction frequency band. However, the increase of resonance coefficient and number of DDWTs will weaken the degree of negative interaction. In addition, with the increase of capacitive current feedback coefficient and grid inductance, the interaction frequency gradually decreases. Finally, the DDWF model is built both on Matlab/Simulink and StarSim + PXI hardware-in-the-loop platform to verify the analytical results. The harmonic interaction characteristics can be used to guide the parameter design of DDWTs, so as to optimise power quality of the wind farm. [ABSTRACT FROM AUTHOR]

This study provides the design, control and comparative analysis of the proposed LCLC coupling hybrid active power filter (LCLC-HAPF). Compared with the conventional L filter coupling active power filters (APFs), LC filter and LCL filter coupling HAPFs (LC-HAPFs and LCL-HAPFs), the proposed LCLC-HAPF provides better switching frequency harmonics elimination, lower dc-link voltage rating and switching loss. Although the LCLC-HAPF has some advantages, two main challenges will still be confronted in practical implementations. Those are stability problems caused by resonance of LCLC filter, and parameter design for the LCLC filter. In this study, a new active damping method is proposed to overcome the high order resonance problem existing in the proposed LCLC-HAPF. After that, the stability analysis and parameter design are given for the proposed LCLC-HAPF. Finally, the effectiveness of the proposed LCLC-HAPF topology is validated through both simulation and experimental studies in comparison with the conventional APFs and HAPFs. [ABSTRACT FROM AUTHOR]

Searching for new anti-poisoning Pt-based catalysts with enhanced activity for alcohol oxidation is the key in direct alcohol fuel cells (DAFCs). However, in the traditional strategy for designing bimetallic or multimetallic alloy is still difficult to achieve a satisfactory heterogeneous electrocatalyst because the activity often depends on only the surface atoms. Herein, we fabricate the multicomponent active sites by creating a sulfide structure on 1D PtNiCo trimetallic nanowires (NWs), to give a PtNiCo/NiCoS interface NWs (IFNWs). Owing to the presence of sulfide interfaces, the PtNiCo/NiCoS IFNWs enable an impressive methanol/ethanol oxidation reaction (MOR/EOR) performance and excellent anti-CO poisoning tolerance. They have the MOR and EOR mass activities of 2.25 Amg-1 Pt and 1.62 Amg-1 Pt, around 1.26, 3.21 and 1.46, 2.96 times higher than those of PtNiCo NWs and commercial Pt/C, respectively. CO-stripping and XPS measurements further demonstrate that the new interfacial structure and optimal bonding of Pt-CO can result in accelerating the removal of surface adsorbed carbonaceous intermediates. Moreover, such a unique structure has also demonstrated a much-improved ability for the electrochemical detection of some important molecules (H2O2 and NH2NH2). [ABSTRACT FROM AUTHOR]

Silicic igneous rocks in the oceanic crust provide insights into the formation of proto-continental crust, which can be investigated by studying rare silicic rocks within ophiolite complexes. This study focuses on plagiogranites that crop out as lenses and blocks in the northeast Jiangxi ophiolite (NJO), located in the eastern segment of the Neoproterozoic Jiangnan Orogen, southern China. The plagiogranites yield a mean SHRIMP U-Pb zircon crystallization age of ca. 995Ma and also record a late thermal event at ca. 220 Ma. The plagiogranites have high Na, very low K, and highly variable rare earth element (REE) concentrations from extremely depleted total REEs to strong enrichment in light REEs. Some samples have adakitic characteristics. Zircons from the plagiogranites have positive eHf(t) values (9.96 to 16.6) and mantle-like δ18O values (5.13 ± 0.21?), indicating a juvenile crustal or mantle source. Based on REE modeling, we propose a two-stage model for the formation of the geochemically variable NJO plagiogranites: (1) High-REE adakitic magmas plagiogranites were generated by 20% partial melting of basaltic oceanic crust; and (2) subsequent fractional crystallization (up to 50%) of these magmas and crystal accumulation produced the low-REE plagiogranites. Our results show that granitic magmas can become highly differentiated in an oceanic setting. The diversity of silicic rocks in the oceanic crust is mainly the result of partial melting of subducted basaltic rocks and subsequent differentiation rather than just fractional crystallization of basaltic magmas. [ABSTRACT FROM AUTHOR]

Trait-based approaches applied to community assembly have led to a considerable advance in understanding the drivers that underlie community dynamics. However, species respond to environmental conditions based on traits, and the role of intraspecific trait variability (ITV) in community assembly during succession has not been studied in detail. Here, we explored the effects of environmental conditions on plant trait composition and tested the role of ITV on understanding the assembly processes throughout a longterm forest succession on the Loess Plateau of China. Thirty plots were established across six successional stages, and 15 functional traits of 210 species were measured. Rao's quadratic entropy of each community with and without accounting for ITV was calculated and then compared with random expectation to evaluate the community functional structure. A structural equation model was used to determine the effects of soil abiotic factors on community functional structure. Community functional structure based on multiple traits transitioned from a stochastic pattern in the early community to a significantly overdispersed pattern in the latest climax community, mainly driven by the increasing niche differentiation of plant height and seed mass. In contrast, community functional structure for most chemical and structure traits showed a neutral but increasing clustering pattern throughout succession. We found that consideration of intraspecific variability did not result in the misreading of the assembly process along a successional gradient; consideration of intraspecific variability only increased the divergence of traits for the latest climax community. Soil NH4-N was an especially important factor that influenced community functional structure and ITV during succession. Our results suggest a change in the dominant assembly mechanism from stochastic to deterministic processes and a strong environmental modification that drives community assembly during a long-term forest succession. Ignoring ITV (except for plant height) may be acceptable in understanding community assembly along a local secondary forest succession in a semiarid ecosystem, such as the Loess Plateau. [ABSTRACT FROM AUTHOR]

The photoperiod sensitivity of rice (Oryza sativa L.) cultivars plays an important role in rice growth and yield formation. To ascertain the different effects of sowing dates on spikelet formation for different photoperiod-sensitive genotypes, 10 sowing dates were selected to assess differences in spikelet differentiation and degeneration for photoperiod-sensitive cultivars yongyou 538 (YY538) and xiushui134 (XS134) and photoperiod- insensitive cultivar chujing27 (CJ27). The yield of the cultivars differed significantly among different sowing dates and was primarily influenced by the spikelet number per panicle. With different sowing dates, shorter daylengths, and increasing temperatures significantly shortened the duration from sowing to heading for YY538 and XS134, while that of CJ27 was less changed and influenced by the average temperature. Rice growth duration was the primary factor limiting dry matter accumulation (DMA), which was correlated with the number of differentiated spikelets (NDS) and the proportion of degenerated spikelets (PGS) in photoperiod-sensitive varieties. High temperature weather with a relatively large temperature gap and strong solar radiation promoted spikelet differentiation in all three cultivars. Extremely high and low temperatures aggravated spikelet degeneration, but YY538 and XS134 were not exposed to low temperatures because their duration of growth was shortened to a greater extent than that of CJ27 with late sowing dates. Under different sowing dates, the NDS and PGS were evaluated by partial least squares regression (PLSR) with DMA, rice growth duration, temperature, and solar radiation. These results provide a reference for sowing date adjustment with climate changes in different regions. [ABSTRACT FROM AUTHOR]

Alkali metal-O2 batteries, by coupling high-capacity alkali metal anodes with gaseous oxygen, possess extremely high gravimetric energy density that is comparable to gasoline and are potential energy storage technologies beyond lithium-ion batteries. The development of alkali metal-O2 batteries has achieved great progress in recent years, from materials to prototype devices and on fundamental mechanisms. The stability of alkali metal-O2 batteries is still poor, however, leading to a huge gap between laboratory research and commercial applications. A series of parasitic reactions result in the instability, which occur during electrochemical discharging and charging. The ubiquitous active oxygen species attack both the organic electrolyte and the carbon cathode, triggering various parasitic reactions. Meanwhile, dendrite growth and volume expansion upon repeated plating/stripping and O2 crossover severely limit the reversibility of alkali metal anodes. Here, an overview of the strategies against these issues is given to improve the stability of nonaqueous alkali metal-O2 batteries, which is discussed from three aspects: air cathodes, alkali metal anodes, and aprotic electrolytes. Furthermore, perspectives for future research of stable alkali metal-O2 batteries are outlined. [ABSTRACT FROM AUTHOR]

Lithium metal is the most promising anode material for next-generation batteries, owing to its high theoretical specific capacity and low electrochemical potential. However, the practical application of lithium metal batteries (LMBs) has been plagued by the issues of uncontrollable lithium deposition. The multifunctional nanostructured anode can modulate the initial nucleation process of lithium before the extension of dendrites. By combing the theoretical design and experimental validation, a novel nucleation strategy is developed by introducing sulfur (S) to graphene. Through first-principles simulations, it is found that S atom doping can improve the Li adsorption ability on a large area around the S doping positions. Consequently, S-doped graphene with five lithiophilic sites rather than a single atomic site can serve as the pristine nucleation area, reducing the uneven Li deposition and improving the electrochemical performance. Modifying Li metal anodes by S-doped graphene enables an ultralow overpotential of 5.5 mV, a high average Coulombic efficiency of 99% over more than 180 cycles at a current density of 0.5 mA cm-2 for 1.0 mAh cm-2, and a high areal capacity of 3 mAh cm-2. This work sheds new light on the rational design of nucleation area materials for dendrite-free LMB. [ABSTRACT FROM AUTHOR]

A Cobalt-catalyzed annulation of 3-aryl-1,2,4-oxadiazolones with 1,3-diynes has been developed, in which reaction temperature variation considerably affects the cyclization orientation and afforded structurely distinctive products in good yields and high regioselectivity. Additionally, the late-stage transformation of the cyclization products into N-containing heterocycles is also demonstrated. [ABSTRACT FROM AUTHOR]

The molecular structure of polymers has a great influence on their thermoelectric properties; however, the relationship between the molecular structure of a polymer and its thermoelectric properties remains unclear. In this work, two benzo[1,2-b:4,5-b']dithiophene (BDT)-based conjugated polymers are designed and synthesized, which contain alkyl side chains or polar side chains. The effects of the polymer side chain on the physicochemical properties are systematically investigated, especially the thermoelectric performance of the polymers after doping with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone and 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane. It is found that the BDT-based conjugated polymer with polar side chains exhibits good miscibility with the dopants, leading to higher thermoelectric properties than those of the polymer with alkyl side chains. This work can serve as a reference for the future design of high-performance organic thermoelectric polymers. [ABSTRACT FROM AUTHOR]

SHRIMP and LA–ICP–MS zircon U–Pb dating, Nd and Hf isotope analyses, 40Ar/39Ar geochronology, and whole‐rock geochemistry indicate three episodes of magmatism in the Dabaoshan ore district, South China: (1) Caledonian dacites (ca. 438 Ma); (2) Indosinian dolerites (ca. 210 Ma); and (3) Yanshanian granodiorites/porphyries (ca. 165 Ma) and basalts (ca. 147 Ma). Episode 1 dacites and episode 3 granodiorites/porphyries are enriched in Rb, Th, U, and LREEs and depleted in Nb, Ta, Sr, P, and Ti. The dacites may have been derived from partial melting of Mesoproterozoic–Paleoproterozoic crustal material, whereas the granodiorites/porphyries were derived mainly from partial melting of a late Mesoproterozoic crustal source with minor inputs of mantle material, according to whole‐rock εNd(t) and zircon εHf(t) values. The geochemical characteristics of episode 2 dolerites and episode 3 basalts, as well as their positive εNd(t) values (3.3–5.9 and 3.5–4.0, respectively), suggest a depleted mantle source. Taking into account the tectonic evolution of the South China Block, we suggest episode 1 dacites and episode 2 dolerites formed in an extensional setting that resulted from lithospheric delamination during the Caledonian intraplate orogeny and orogenic collapse during the Indosinian intraplate orogeny. Episode 3 granodiorites/porphyries and basalts formed in a back‐arc extensional setting in response to the westwards subduction of the Palaeo‐Pacific Plate beneath the South China Block. The timing of the three episodes of magmatism coincides roughly with the published ages of mineralization in the Dabaoshan ore district, suggesting a genetic relationship. [ABSTRACT FROM AUTHOR]