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With the aim of resolving the threshold voltage drift problem of the silicon carbide metal-oxide-semiconductor field-effect transistor (SiC mosfet), which is caused by traps, this article presents a study of the laws for the different traps that affect threshold voltage drift and also clarifies the details of the trap that leads to the SiC mosfet threshold voltage drift. First, based on use of the transient current method for trap characterization, we eliminate the interference from the SiC bulk traps, and the time constant spectrum of the gate oxide trap is then obtained accurately. Second, the effects of the different traps on the threshold voltage are studied by filling or releasing the charges from traps with different time constants. The main trap time constant that leads to the SiC mosfet threshold voltage drift is revealed to be 300 ms, whereas the other trap only affects the current and hardly contributes to the threshold voltage drift. Finally, based on the activation energies of the different traps, it is inferred that the trapping mechanism of the traps are the trap-assisted tunneling effect and the hot electron emission effect, and the corresponding trap types are identified as the oxide trap and the interface trap, respectively.

This paper presents a newly developed high-performance mobile single-photon ionization time-of-flight mass spectrometry (M-SPI-TOFMS) system for on-line analysis and stereoscopic monitoring of complex gas mixtures. The system is designed for stereoscopic imaging to map the distribution of volatile organic compounds (VOCs) and trace their emission sources in urban areas and industrial parks. It mainly consists of a SPI-TOFMS instrument, a customized commercial vehicle, a meteorological five-parameter monitor with GPS, a high-power generator, and an uninterruptible power supply. The SPI technique, using a 118 nm VUV lamp, can ionize compounds with an ionization potential below 10.78 eV. Mass spectra obtained using this technique show the profiles of various VOCs and some inorganic compounds. The VOCs composition information and mobile location data are simultaneously sent to the GIS software. In GIS software, this data is used for real-time stereoscopic imaging of VOC distribution and precise tracking of VOC movement. The system can achieve a spatial data resolution of 0.69 mm at 25 km/h due to the microsecond detection speed of the M-SPI-TOFMS instrument. The laboratory test provides a rapid overview characterization of benzene, toluene, and xylene. The M-SPI-TOFMS has limits of detection and mass resolution of 33.7 pptv and 1060, respectively. Several field applications were carried out using M-SPI-TOFMS at various locations to identify VOC sources near different factories. The M-SPI-TOFMS system has a navigation monitoring speed of 25 km/h with a time resolution of 1 s. The widespread use of this system will provide accurate data to support environmental management departments in formulating VOCs pollution control policies and improving control efficiency.

We explore the extent to which differences in countries' formal and informal institutions reduce cross-border leveraged buyout transactions and the potential influence these same institutions have on how private equity (PE) investors choose to enter these transactions. Although institutional differences have frequently been viewed as barriers to cross-border investment, we find evidence that these same differences may motivate a PE firm's decision to enter the transaction with a syndicate of firms rather than undertaking the transaction on their own. Cultural differences between a PE firm and the target nation are significantly related to the choice to enter the deal via a multinational syndicate. The varying nationalities within the syndicate contribute to enhanced familiarity, with average institutional distances between the syndicate and target firms being significantly lower than for single-PE-1ed deals. Overall, deals undertaken by syndicates are more likely to be successfully completed and require less time in negotiation. These results persist even after accounting for selection bias with regard to target country choice. We explore whether other features of the syndicate are responsible for improved deal outcomes, such as repeated transactions with the same partners, but find no evidence that this is the case. KEYWORDS Institutional Environment, Leveraged Buyouts, Private Equity, Syndicates, 1 | INTRODUCTION Successful corporate reorganization is difficult in any environment, but undertaking this task in a cross-border context is particularly challenging. From the investor's perspective, the formal and informal [...]

High-quality protein–ligand complex structures provide the basis for understanding the nature of noncovalent binding interactions at the atomic level and enable structure-based drug design. However, experimentally determined complex structures are scarce compared with the vast chemical space. In this study, we addressed this issue by constructing the BindingNet data set via comparative complex structure modeling, which contains 69,816 modeled high-quality protein–ligand complex structures with experimental binding affinity data. BindingNet provides valuable insights into investigating protein–ligand interactions, allowing visual inspection and interpretation of structural analogues’ structure–activity relationships. It can also be used for evaluating machine-learning-based scoring functions. Our results indicate that machine learning models trained on BindingNet could reduce the bias caused by buried solvent-accessible surface area, as we previously found for models trained on the PDBbind data set. We also discussed strategies to improve BindingNet and its potential utilization for benchmarking the molecular docking methods and ligand binding free energy calculation approaches. The BindingNet complements PDBbind in constructing a sufficient and unbiased protein–ligand binding data set and is freely available at http://bindingnet.huanglab.org.cn.

Advanced two-dimensional (2D) MXenes have been extensively researched as electrode materials for flexible supercapacitors due to their excellent electronic performance and flexibility. Herein, a facile and effective approach is adopted to synthesize a polypyrrole@bacterial cellulose/MXene (PPy@BC/MXene) hybrid film through a plunge-freezing and vacuum-assisted filtration self-assembly strategy. We have constructed an ordered “building frame structure” with MXene as the “beam and slab” and polypyrrole@bacterial cellulose (PPy@BC) as the “pillar.” Benefiting from this vertical bridge, rapid interlaminar electroconductivity, unimpeded ion diffusion channels, and sufficient reactivity, the synthesized PPy@BC/MXene-25% electrode has achieved a high specific capacitance of 807 F g–1at 0.05 mA cm–2and a capacitance retention of 97.51% after 10 000 cycles at 20 mA cm–2. Besides, PPy@BC/MXene-25% exhibits high strain at break (∼10.8%) and high tensile strength (∼310 MPa). Moreover, the asymmetric microsupercapacitor PPy@BC/MXene-25%//MXene is assembled with PPy@BC/MXene-25% as the anode, which presents an average capacity of 464 F g–1at 0.05 mA cm–2. The specific energy density of the PPy@BC/MXene-25%//MXene capacitor has achieved 135.3 μWh cm–2at a power density of 435.4 μW cm–2at 0.5 mA cm–2. The novel approach exploits a new way to design conductive freestanding flexible electrodes with significantly enhanced electrochemical properties.

A central question in neural tissue engineering is how the tissue-engineered nerve (TEN) translates detailed transcriptional signals associated with peripheral nerve regeneration into meaningful biological processes. Here, we report a skin-derived precursor-induced Schwann cell (SKP-SC)-mediated chitosan/silk fibroin-fabricated tissue-engineered nerve graft (SKP–SCs-TEN) that can promote sciatic nerve regeneration and functional restoration nearly to the levels achieved by autologous nerve grafts according to behavioral, histological, and electrophysiological evidence. For achieving better effect of neuroregeneration, this is the first time to jointly apply a dynamic perfusion bioreactor and the ascorbic acid to stimulate the SKP-SCs secretion of extracellular matrix (ECM). To overcome the limitation of traditional tissue-engineered nerve grafts, jointly utilizing SKP-SCs and their ECM components were motivated by the thought of prolongating the effect of support cells and their bioactive cues that promote peripheral nerve regeneration. To further explore the regulatory model of gene expression and the related molecular mechanisms involved in tissue engineering-aided peripheral nerve regeneration, we performed a cDNA microarray analysis of gene expression profiling, a comprehensive bioinformatics analysis and a validation study on the grafted segments and dorsal root ganglia tissues. A wealth of transcriptomic and bioinformatics data has revealed complex molecular networks and orchestrated functional regulation that may be responsible for the effects of SKP-SCs-TEN on promoting peripheral nerve regeneration. Our work provides new insights into transcriptomic features and patterns of molecular regulation in nerve functional recovery aided by SKP-SCs-TEN that sheds light on the broader possibilities for novel repair strategies of peripheral nerve injury.

Prenatal molecular genetic testing for familial variants that cause inherited disorders has been performed for decades and is accepted as standard of care. However, the spectrum of genes considered for prenatal testing is expanding because of genetic testing for hereditary cancer risk (HCR) and inclusion of conditions with associated cancer risk in carrier screening panels. A few of these disorders, such as ataxia telangiectasia and Bloom syndrome, include increased cancer risk as part of the phenotype, already meet professional guidelines for prenatal testing, and may be associated with increased cancer risk in heterozygous carriers. In addition, recent studies implicate heterozygosity for variants in lysosomal storage disease genes in HCR etiology. Currently, there is no specific professional guidance regarding prenatal testing for HCR. To determine the prevalence of such testing, we reviewed 1345 consecutive prenatal specimens received in our laboratory for familial variant-specific testing and identified 65 (4.8%) with a known or likely HCR component, plus 210 (15.6%) for lysosomal storage disease. These specimens were classified into five distinct categories for clarity and to enable evaluation. Our experience assessing prenatal specimens for variants associated with HCR, with or without a constitutional phenotype, provides metrics for and contributes to the points to consider in prenatal testing for HCR.

This study explores the mechanism of action of Danhongqing formula (DHQ), a compound-based Chinese medicine formula, in the treatment of cholestatic liver fibrosis.

Passive acoustic mapping (PAM) has emerged as a valuable imaging modality for monitoring the cavitation activity in focused ultrasound therapies. When it comes to imaging in the human abdomen, convex arrays are preferred due to their large acoustic window. However, existing PAM methods for convex arrays rely on the computationally expensive delay-and-sum (DAS) operation limiting the image reconstruction speed when the field-of-view (FOV) is large. In this work, we propose an efficient and frequency-selective PAM method for convex arrays. This method is based on projecting the helical wave spectrum (HWS) between cylindrical surfaces in the imaging field. Both the in silico and in vitro experiments showed that the HWS method has comparable image quality and similar acoustic cavitation source localization accuracy as the DAS-based methods. Compared to the frequency-domain and time-domain DAS methods, the time-complexity of the HWS method is reduced by one order and two orders of magnitude, respectively. A parallel implementation of the HWS method realized millisecond-level image reconstruction speed. We also show that the HWS method is inherently capable of mapping microbubble (MB) cavitation activity of different status, i.e., no cavitation, stable cavitation, or inertial cavitation. After compensating for the lens effects of the convex array, we further combined PAM formed by the HWS method and B-mode imaging as a real-time dual-mode imaging approach to map the anatomical location where MBs cavitate in a liver phantom experiment. This method may find use in applications where convex arrays are required for cavitation activity monitoring in real time.

Abstract: Objective: To evaluate and describe CT and endoscopic imaging findings in patients with pathologically confirmed gastrointestinal tract lymphangiomas. Methods: Findings from imaging examinations in 6 patients with pathologically confirmed lymphangioma were retrospectively reviewed (computed tomographic images obtained in 6 patients and endoscopic images obtained in 4 patients were available for review). Two radiologists evaluated lesion location, size, shape, edge, number, attenuation, the thickness of capsule wall and the degree of enhancement through PACS or workstation. Results: Lymphangiomas in gastrointestinal tract showed similar features in CT imaging: Contrast-enhanced CT scan showed the oval submucosal masses with homogeneous low attenuation. The lymphangioma appeared as a well-defined, smoothly marginated and non-enhancing cystic mass with intact overlying intestinal mucosa. In one case, the lymphangiomas were multiple with volvulus. Remarkably, CT imaging showed 2 patients with intussusception due to the mass. Endoscopic photographs manifested multiple colplanate mucosal protrusions in the gastric wall or intestinal wall. One case showed submucosal pedunculated proliferative lesion with adenomatous surface. Conclusions: Lymphangiomas exhibited typical appearances that reflected their cystic pathologic features. They showed similar features in CT imaging: well-demarcated, non-enhancing, homogeneous low attenuation cystic masses with intact overlying mucosa. Endoscopic photographs showed submucosal masses with distension of overlying mucosal vessels.

Big data and bursting cloud computing technologies have facilitated an increasing trend of outsourcing data-driven services to the cloud, where the reverse kNN (RkNN) query is a popularly outsourced query service. The RkNN query aims to retrieve objects having the query object as kNN and widely applied in the product recommendation. Considering privacy concerns, the outsourced query services are demanded to protect data privacy, and consequently a series of privacy-preserving query solutions have been put forth. Nevertheless, RkNN query over high-dimensional data has not been studied to date. In this work, we design the first efficient and privacy-preserving RkNN query scheme over encrypted high-dimensional data, named PHRkNN. Specifically, we first introduce a pivot filter condition for the RkNN query and utilize it to deliberately design a pivot filter R-tree (PFR-tree) to organize the high-dimensional dataset such that the RkNN query has sublinear query efficiency. Then, we propose our PHRkNN scheme by designing some homomorphic encryption based private algorithms and applying them to privately achieve PFR-tree based RkNN query. After that, we propose an oblivious PHRkNN scheme on the basis of the PHRkNN scheme by designing a private random tree permutation (PRTP) algorithm to protect the access pattern privacy. The security of our PHRkNN scheme and oblivious PHRkNN scheme is proved by the simulation-based security analysis. The performance is verified through computational costs and communication overheads evaluation.

In this letter, a Sigmoid-shaped curve is proposed to enhance the contrast between blood vessels and static tissue in optical coherence tomography angiography. Different from the conventional parabolic curve, the Sigmoid-shaped function biases the decorrelation histogram towards both ends, which suppresses the static tissue background as well as enhances the flow signal in the blood vessels region. An intensity mask is generated to remove the decorrelation signal at the noise level and then the filtering method is used to improve the image quality. A white diffuse plate has been used and verified to remove the static background deeper when our method is applied, and the z-axis range of static signal increases from $27.3~\mu $ m to $31.9~\mu $ m, indicating the extent of decorrelation has been improved by 17%. We demonstrate that the contrast of vascular image of the mouse ear has been improved from 32.6 to 43.1, compared with the conventional decorrelation method.

The emergence of cloud computing enables various healthcare institutions to outsource pre-diagnostic models and provide timely and convenient services for patients. However, healthcare institutions and patients have serious concerns about potential privacy leakage as cloud servers cannot be fully trusted. In this paper, a privacy-preserving cloud-assisted medical pre-diagnosis scheme, named NAIAD, is proposed, where patients can securely query the outsourced model and obtain their pre-diagnostic results. Specifically, the pre-diagnostic model is constructed on $k$k-Nearest Neighbor ($k$kNN), and Mahalanobis Distance (MD) is chosen as the similarity metric to achieve high accuracy. Accordingly, a secure MD-based comparison method (SMDC) is designed based on a matrix encryption technique. The method is a basic module of NAIAD that enables cloud servers to compare encrypted medical records and achieve privacy-preserving $k$kNN-based pre-diagnosis with linear complexity. To further improve the computational efficiency, medical records are first clustered and encrypted to construct a hierarchical index tree, then patients can query the tree to speed up the query process. Detailed security analysis indicates NAIAD can resist closeness-same-pattern chosen-plaintext attack, and extensive experiments on real-world and synthetic databases demonstrate NAIAD has high query efficiency and pre-diagnosis accuracy.

Intrauterine adhesion is a major cause of female reproductive disorders. Although we and others uncontrolled pilot studies showed that treatment with autologous bone marrow stem cells made a few patients with severe intrauterine adhesion obtain live birth, no large sample randomized controlled studies on this therapeutic strategy in such patients have been reported so far. To verify if the therapy of autologous bone marrow stem cells-scaffold is superior to traditional treatment in moderate to severe intrauterine adhesion patients in increasing their ongoing pregnancy rate, we conducted this randomized controlled clinical trial. Totally 195 participants with moderate to severe intrauterine adhesion were screened and 152 of them were randomly assigned in a 1:1 ratio to either group with autologous bone marrow stem cells-scaffold plus Foley balloon catheter or group with only Foley balloon catheter (control group) from February 2016 to January 2020. The per-protocol analysis included 140 participants: 72 in bone marrow stem cells-scaffold group and 68 in control group. The ongoing pregnancy occurred in 45/72 (62.5%) participants in the bone marrow stem cells-scaffold group which was significantly higher than that in the control group (28/68, 41.2%) (RR=1.52, 95%CI 1.08–2.12, P=0.012). The situation was similar in live birth rate (bone marrow stem cells-scaffold group 56.9% (41/72) vs.control group 38.2% (26/68), RR=1.49, 95%CI 1.04–2.14, P=0.027). Compared with control group, participants in bone marrow stem cells-scaffold group showed more menstrual blood volume in the 3rd and 6th cycles and maximal endometrial thickness in the 6th cycle after hysteroscopic adhesiolysis. The incidence of mild placenta accrete was increased in bone marrow stem cells-scaffold group and no severe adverse effects were observed. In conclusion, transplantation of bone marrow stem cells-scaffold into uterine cavities of the participants with moderate to severe intrauterine adhesion increased their ongoing pregnancy and live birth rates, and this therapy was relatively safe.

Objective: Summarize and analyze the characteristics of patients with Multiple Endocrine Neoplasia type 1 (MEN-1) who were diagnosed with malignant tumors that do not belong to MEN-1 components. Methods: Clinical data from patients with MEN-1 who visited Peking Union Medical College Hospital between April 2012 and April 2022 were collected. We compared the clinical characteristics of patients with malignant tumors outside of their MEN-1 components to those without additional tumors. MEN-1 gene testing was performed on most of these patients using Sanger sequencing, whole-exome sequencing, or MLPA. Results: A total of 221 MEN-1 patients were diagnosed, of which 23 (10.40%) were found to have malignant tumors that did not belong to MEN-1 components, including papillary thyroid carcinoma (PTC) (4.52%), breast cancer (1.81%), urologic neoplasms (1.35%), primary hepatic carcinoma (PCC) (0.09%), meningeal sarcoma (0.05%), glioblastoma (0.05%), cervical cancer (0.05%), and lung carcinoma (0.05%). MEN-1 gene mutations were identified in 11 patients, including missense mutations, frameshift mutations, and splice mutations. The prevalence of each endocrine neoplasm, particularly gastroenteropancreatic neuroendocrine tumor, was higher in MEN-1 patients with other malignant tumors compared to MEN-1 patients without malignant tumors. Conclusion: Our retrospective study revealed a higher incidence of non-MEN-1 component malignant tumors in MEN-1 patients, especially breast cancer, PTC, and urologic neoplasms. These patients also exhibit more severe clinical phenotypes of MEN-1.

• The CNTs coated with various Ni-based NiM nanoalloys are CVD grown on the graphene nanoscrolls to form unique carbon material scaffold. • The electrons of encapsulated NiM nanoalloys can traverse through the CNT to the outmost loading (CoP) by electron traversing effect. • Due to the varying d-electron orbital characteristic of NiMs, the encapsulated various nims can weaken the interactions of the outmost CoP with H* and push the downshift of the d-band center to different degrees to optimize the HER activity. • The catalytic performance of the outmost CoP can be optimized by changing the encapsulated metal nanoparticles in the unique carbon material scaffold, which is a novel d-band center control engineering strategy for HER. Attaining a highly efficient and inexpensive electrocatalyst is significant for the hydrogen evolution reaction (HER) but still challenging nowadays. The transition-metal phosphides (TMPs) catalysts with platinum-like electronic structures are a potential candidate for the HER, but those are prone to be strongly bound with hydrogen intermediates (H*), resulting in sluggish HER kinetics. Herein we report a unique hybrid structure of CoP anchored on graphene nanoscrolls@carbon nano tubes (CNTs) scaffold (Ni M @C-CoP) encapsulating various Ni M (M =Zn, Mo, Ni, Co) bimetal nanoalloy via chemical vapor deposition (CVD) growth of CNT on graphene nanoscrolls followed by the impregnation of cobalt precursors and phosphorization for efficiently electrocatalytic hydrogen evolution. CoP nanoparticles mainly scattered at the tip of CNT branches which exhibited the analogical ''Three-layer core-shell'' structures. Experiments and density functional theory(DFT) calculations consistently disclose that the encapsulated various NiMs can offer different numbers of electrons to weaken the interactions of outmost CoP with H* and push the downshift of the d -band center to different degrees as well as stabilize the outmost CoP nanoparticles to gain catalytic stability via the electron traversing effect. The electrocatalytic HER activity can be maximumly enhanced with low overpotentials of 78 mV (alkaline) and 89 mV (acidic) at a current density of 10 mA/cm2 and sustained at least 24 h especially for NiZn@C-CoP catalyst. This novel system is distinct from conventional three-layer heterostructure, providing a specially thought of d -band center control engineering strategy for the design of heterogeneous catalysts and expanding to other electrocatalysts, energy storage, sensing, and other applications. Herein we report a unique hybrid structure of CoP anchored on graphene nanoscrolls@CNTs scaffold (NiM@C-CoP) encapsulating varying NiM (M=Zn, Mo, Ni, Co) bimetal nanoalloy for efficiently electrocatalytic hydrogen evolution. Experiments and density functional theory calculations consistently disclose that the encapsulated NiMs can weaken the interactions of outmost CoP with H* and push the downshift of the d-band center to different degrees via the electron traversing effect. [Display omitted] [ABSTRACT FROM AUTHOR]

In engineering application, the saturation voltage drop ( $V_{\text {CE}}$ ) method is widely used for junction temperature prediction. However, it is difficult to characterize the peak temperature by the virtual junction temperature measured by the $V_{\text {CE}}$ method. In this article, the reasons why the virtual junction temperature is lower than the peak junction temperature were explained by analyzing the internal current distributions of the module for different temperature distributions. Using an equivalent model composed of discrete devices, the virtual junction temperatures for different temperature distributions and measuring currents were measured. The current-weighted temperatures for different measuring currents were also calculated using the branch current. The virtual junction temperature and current-weighted temperature were compared and investigated in combination with simulation results under ideal conditions. The variation law of the virtual junction temperature with the sense current and the temperature distribution was determined, which will aid in the measurement of the junction temperature in engineering.

The advance of cloud computing has driven an emerging trend of outsourcing the rapidly growing data and query services to a powerful cloud for easing the local storage and computing pressure. Meanwhile, when taking data privacy into account, data are usually outsourced to the cloud in an encrypted form. As a result, query services have to be performed over the encrypted data. Among all kinds of query services, the reverse kNN query is highly popular in various applications, such as taxi dispatching and targeted push of multimedia information, but its privacy has not received sufficient attention. To our best knowledge, many existing privacy-preserving reverse kNN query schemes still have some limitations on the query result accuracy, dataset privacy, and flexible support for the choice of the query object and the parameter k. Aiming at addressing these limitations, in this paper, we propose an efficient and privacy-preserving reverse kNN query scheme over encrypted data, named PRkNN. Specifically, we first design a modified M-tree (MM-tree) to index the dataset and further present an MM-Tree based reverse kNN query algorithm in the filter and refinement framework. Then, we leverage the lightweight matrix encryption to carefully design a filter predicate encryption scheme (FPE) and a refinement predicate encryption scheme (RPE); and propose our PRkNN scheme by applying them to protect the privacy of the MM-Tree based reverse kNN query algorithm. Detailed security analysis shows that FPE and RPE schemes are selectively secure, and our PRkNN scheme can preserve both query privacy and dataset privacy. In addition, we conduct extensive experiments to evaluate the performance of our scheme, and the results demonstrate that our scheme is efficient.

Designing high-performance carbonous electrodes for capacitive deionization with remarkable salt adsorption capacity (SAC) and outstanding salt adsorption rate (SAR) is quite significant yet challenging for brackish water desalination. Herein, a unique gelation-assisted strategy is proposed to tailor two-dimensional B and N-enriched carbon nanosheets (BNCTs) for efficient desalination. During the synthesis process, boric acid and polyvinyl alcohol were cross-linked to form a gelation template for the carbon precursor (polyethyleneimine), which endows BNCTs with ultrathin thickness (∼2 nm) and ultrahigh heteroatoms doping level (14.5 atom % of B and 14.8 atom % of N) after freeze-drying and pyrolysis. The laminar B, N-doped carbon enables an excellent SAC of 42.5 mg g–1and fast SAR of 4.25 mg g–1min–1in 500 mg L–1NaCl solution, both of which are four times as much as those of activated carbon. Moreover, the density functional theory (DFT) calculation demonstrates that the dual doping of B and N atoms firmly enhances the adsorption capacity of Na+, leading to a prominent chemical SAC for brackish water. This work paves a new way to rationally integrate both conducive surface morphology and systematic effects of B, N doping to construct high-efficiency carbonaceous electrodes for desalination.

The charge transfer mechanism of the g-C3N4/MoS2heterojunction is still disputed. Some regard it as a type I pathway, some regard it as a type II pathway, and still some regard it as a Z-scheme pathway. Especially, the results obtained by density functional theory (DFT) calculations are not totally in agreement. Here, we constructed four g-C3N4/MoS2heterojunctions on the basis of the aperture alignment modes of g-C3N4and MoS2. Their morphology and photocatalytic activity were investigated via first-principles and excited state dynamics simulations. By systemically comparing the interfacial binding energy and electronic structure (e.g., band structure, electrostatic potential, and band edge positions) of g-C3N4/MoS2heterojunctions, we found that both type I and type II band alignment structures could be obtained. Moreover, the calculated lifetimes of interlayer photogenerated electrons and holes show that type II g-C3N4/MoS2tends to favor a general type II pathway rather than a Z-scheme pathway. This study could provide a deep understanding of the photocatalytic mechanism of g-C3N4/MoS2van der Waals heterostructures, which will be of great use for applications in photocatalysis.

Electrochemiluminescence (ECL) imaging, as an optical technology, has been developed at full tilt in the field of life science and nanomaterials. However, the relatively low ECL intensity or the high co-reactant concentration needed in the electrochemical reaction blocks its practical application. Here, we developed an ECL imaging system based on the rGO-TiO2–xcomposite material, where the co-reactant, reactive oxygen species (ROS), is generated in situ under the synergetic effect of of ultrasound (US) and electric irradiation. The rGO-TiO2–xcomposites facilitate the separation of electron (e–) and hole (h+) pairs and inhibit recombination triggered by external US irradiation due to the high electroconductivity of rGO and oxygen-deficient structures of TiO2, thus significantly boosting ROS generation. Furthermore, the increased defects on rGO accelerate the electron transfer rate, improving the electrocatalytic performance of the composite and forming more ROS. This high ultrasonic–electric synergistic efficacy is demonstrated through the enhancement of photon emission. Compared with the luminescence intensity triggered by US irradiation and electric field, an enhancement of ∼20-fold and 10-fold of the US combined with electric field-triggered emission is observed from this composite. Under the optimized conditions, using dopamine (DA) as a model target, the sensitivity of the US combined ECL strategy for detection of DA is two orders of magnitude higher than that of the ECL method. The successful detection of DA at low concentrations makes us believe that this strategy provides the possibility of applying ECL imaging for cellular single-molecule analysis and cancer therapy.

Repeated homoploid hybrid speciation (HHS) events with the same parental species have rarely been reported. In this study, we used population transcriptome data to test paraphyly and HHS events in the conifer Picea brachytyla. Our analyses revealed non-sister relationships for two lineages of P. brachytyla, with the southern lineage being placed within the re-circumscribed P. likiangensisspecies complex (PLSC) and P. brachytyla sensu stricto(s.s.) consisted solely of the northern lineage, forming a distinct clade that is paratactic to both the PLSC and P. wilsonii. Our phylogenetic and coalescent analyses suggested that P. brachytylas.s. arose from HHS between the ancestor of the PLSC before its diversification and P. wilsoniithrough an intermediate hybrid lineage at an early stage and backcrossing to the ancestral PLSC. Additionally, P. purpureashares the same parents and an extinct lineage with P. brachytylas.s. but backcrossing to the other parent, P. wilsoniiat a later stage. We reveal the first case that backcrossing to different parents of the same extinct hybrid lineage produced two different hybrid species. Our results highlight the existence of more reticulate evolution during species diversification in the spruce genus and more complex homoploid hybrid events than previously identified.

The study aims to search for green, non-toxic bio-based plasticizers to replace traditional o-benzene petroleum-based plasticizers used in polyvinyl chloride films for automotive interior decoration. Three bio-based plasticizers – epoxy, polyester, and citrate were chosen and characterized based on refractive index, viscosity, and plasticizing efficiency. The three types of bio-based plasticizers were then applied to PVC films for automotive interiors. The odor rating, emission properties test, tensile test, dynamic thermomechanical test, low-temperature fatigue resistance test, and heat performance test were used to characterize the polyvinyl chloride film’s application properties. The results showed that the properties of epoxy plasticizer and polyester plasticizer are very close to those of traditional o-benzene petroleum-based plasticizers. In particular, polyvinyl chloride films prepared from polyester plasticizers have advantages in mechanical properties. The strength, elongation, and elasticity characteristics of PVC films plasticized with polyester bio-based plasticizer are 8.77 MPa, 533.92%, and 129.74 Nm, respectively. While the PVC films plasticized with epoxy bio-based plasticizer has an excellent heat resistance and aging resistance, with an initial gel temperature of 185.668 °C. However, the polyvinyl chloride film prepared with citrate plasticizer does not meet the requirements for application in automotive interiors due to its poor emission performance.

Purpose: To retrospectively summarize the clinical features of acromegaly complicated with fulminant pituitary apoplexy and analyze the prognostic factors to guide early identification and timely treatment of such patients. Methods: A retrospective analysis was carried out to summarize the clinical manifestations, hormone changes, imaging, treatment and follow-up of ten patients with acromegaly complicated with fulminant pituitary apoplexy admitted to our hospital from February 2013 to September 2021. Results: The mean age of the ten patients (five males and five females) at the time of pituitary apoplexy was 37.1 ± 13.4 years old. There were nine cases with sudden severe headaches and five cases with visual impairment. All patients had pituitary macroadenomas, of which six cases with Knosp grade ≥3. The level of GH/IGF-1 hormone after pituitary apoplexy was lower compared with pre-apoplexy, and 1 patient reached biochemical remission spontaneously. Seven patients underwent transsphenoidal pituitary surgery after apoplexy and one patient was treated with long-acting somatostatin analog. The biochemical remission rate was 37.5% in eight patients immediately after treatment and 50% at the last follow-up. Patients with Knosp grade ≥3 were less likely to achieve biochemical remission than those with Knosp grade <3 (16.7% vs. 100%, p= 0.048), and patients who achieved biochemical remission had a smaller maximum tumor diameter [20.1 (20.1,28.0) mm vs. 44.0 (44.0,60) mm, p= 0.016]. Conclusion: Acromegaly complicated with fulminant pituitary apoplexy remains a diagnostic and therapeutic challenge.

Emerging studies have suggested an essential role of fibroblast metabolic reprogramming in the pathogenesis of arthrofibrosis. The metabolic modulator metformin appears to be a therapeutic candidate for fibrotic disorders. However, whether metformin could alleviate arthrofibrosis has not been defined. In this study we have determined if treatment with metformin has beneficial effect on arthrofibrosis and its underlying mechanism.

Cyanobacteria have numerous biotechnological applications in the environment, industry, pharmaceutics, food, feed, and energy which is why future cascading biorefineries are believed to employ cyanobacteria as their feedstock. The present study evaluated the potential of a newly isolated cyanobacterium for its applications in the multiproduct biorefinery. Based on morphology and the gene sequence of 23S rRNA, the strain was identified as Trichocoleus desertorum. Various abiotic growth factors including light, pH, and nutrients were optimized to achieve enhanced biomass production using various wastewaters as low-cost growth media. Accordingly, a 2.24-fold to 6.97-fold higher biomass production (gL-1) and biomass productivity of 0.86 gL-1d-1with a CO2fixation rate of 1.576 gL-1d-1was achieved when cultured in synthetic wastewater. Besides, the impact of wastewater cultivation was studied on the biosynthesis of valuable metabolites including proteins, carbohydrates, lipids, and pigments. Accordingly, the lipid content of the wastewater-cultivated strain was increased from 24 to 30%, and protein content was increased from 27 to 46%. The lipids were trans-esterified to biodiesel which was turned out to be good quality biodiesel, as revealed through GC-MS analysis. Additionally, the wastewater-cultivated strain produced 117.35 mgg-1(11.73 % of the total dried biomass) of phycobilin in response to nutrient manipulation, where phycocyanin was shown to be the most prominent pigment with a yield of 94.7 mgg-1, which covered 80% of the total pigments. These remarkable features reflected the promising potential of this strain to be employed as a feedstock in the multiproduct biorefinery.

Uveal melanoma (UM) is the most common primary intraocular malignancy in adults. However, challenges in early diagnosis, high risk of liver metastasis, and lack of effective targeted therapy lead to poor prognosis and high mortality of UM. Therefore, generating an effective molecular tool for UM diagnosis and targeted treatment is of great significance. In this study, a UM-specific DNA aptamer, PZ-1, was successfully developed, which could specifically distinguish molecular differences between UM cells and noncancerous cells with nanomolar-range affinity and presented excellent recognition ability for UM in vivo and clinical UM tissues. Subsequently, the binding target of PZ-1 on UM cells was identified as JUP (junction plakoglobin) protein, which held great potential as a biomarker and therapeutic target for UM. Meanwhile, the strong stability and internalization capacity of PZ-1 were also determined, and a UM-specific aptamer-guided “nanoship” was engineered to load and selectively release doxorubicin (Dox) to targeted UM cells, with lower toxicity to nontumor cells. Taken together, the UM-specific aptamer PZ-1 could serve as a molecular tool to discover the potential biomarker for UM and to achieve the targeted therapy of UM.

Plasmonic nanostructures have shown immense potential in photocatalysis because of their distinct photochemical properties associated with tunable photoresponses and strong light–matter interactions. The introduction of highly active sites is essential to fully exploit the potential of plasmonic nanostructures in photocatalysis, considering the inferior intrinsic activities of typical plasmonic metals. This review focuses on active site-engineered plasmonic nanostructures with enhanced photocatalytic performance, wherein the active sites are classified into four types (i.e., metallic sites, defect sites, ligand-grafted sites, and interface sites). The synergy between active sites and plasmonic nanostructures in photocatalysis is discussed in detail after briefly introducing the material synthesis and characterization methods. Active sites can promote the coupling of solar energy harvested by plasmonic metal to catalytic reactions in the form of local electromagnetic fields, hot carriers, and photothermal heating. Moreover, efficient energy coupling potentially regulates the reaction pathway by facilitating the excited state formation of reactants, changing the status of active sites, and creating additional active sites using photoexcited plasmonic metals. Afterward, the application of active site-engineered plasmonic nanostructures in emerging photocatalytic reactions is summarized. Finally, a summary and perspective of the existing challenges and future opportunities are presented. This review aims to deliver some insights into plasmonic photocatalysis from the perspective of active sites, expediting the discovery of high-performance plasmonic photocatalysts.

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Changes in the electrical properties and trap characteristics of flexible low-temperature polysilicon thin-film transistors (TFTs) under the application of uniaxial bending strains and during repetitive bending cycles were investigated. When the bending strain increased, the transfer curve showed a negative shift, the output current decreased, and the subthreshold slope increased. After the bending strains were removed, the electrical performance showed recovery behavior, but the device performance could not return fully to its original state. The devices were also subjected to repetitive bending cycles. The transfer curves showed a positive shift after $10^{{4}}$ bending cycles and the output current increased. Using the transient current method, it was established that the detrapping time constant of the traps decreased and the peak amplitudes increased as a result of both the bending strain and the bending cycles. However, while the trap activation energy was not changed by static bending, it did decrease after the repetitive bending cycles. Both the changes in the electrical properties and the time constant spectra confirm that the trap state density increased as a result of the bending processes. However, the different trapping behaviors contributed to different degradations in the device’s electrical properties.

Image segmentation is important in improving the diagnostic capability of ultrasound computed tomography (USCT) and photoacoustic computed tomography (PACT), as it can be included in the image reconstruction process to improve image quality and quantification abilities. Segmenting the imaged object out of the background using image domain methods is easily complicated by low contrast, noise, and artifacts in the reconstructed image. Here, we introduce a new signal domain object segmentation method for USCT and PACT which does not require image reconstruction beforehand and is automatic, robust, computationally efficient, accurate, and straightforward. We first establish the relationship between the time-of-flight (TOF) of the received first arrival waves and the object’s boundary which is described by ellipse equations. Then, we show that the ellipses are tangent to the boundary. By looking for tangent points on the common tangent of neighboring ellipses, the boundary can be approximated with high fidelity. Imaging experiments of human fingers and mice cross sections showed that our method provided equivalent or better segmentations than the optimal ones by active contours. In summary, our method greatly reduces the overall complexity of object segmentation and shows great potential in eliminating user dependency without sacrificing segmentation accuracy. The method can be further seamlessly incorporated into algorithms for other processing purposes in USCT and PACT, such as high-quality image reconstruction.

The effects of reverse pulse electrical stress on the electrical and trapping properties of Depletion-Mode (D-Mode) GaN high-electron-mobility transistors (HEMTs) are investigated in this paper. The results of HEMT testing show that the device’s electrical characteristics in the OFF-state are degraded after reverse pulse electrical stress cycling, along with the gate-to-source reverse current and drain-to-source leakage current characteristics. In particular, three traps in the device are identified using the voltage-transient method, and the trapping effects in the HEMT are investigated after 70000 pulses of gate reverse electrical stress are applied. The sources of the traps identified in the study include interface traps near the surface of AlGaN or at the SiN interface (DP1), intrinsic defects such as N antisites in the GaN buffer (DP2), and traps in the gate-drain access region (DP3). Comparison with the transient voltage characteristics of the original device shows that the absolute amplitudes of the traps in the device increase after application of the electrical stress, thus indicating an increment in the trap density. It was found that DP1 remained unchanged before and after stress application, which may be the result of an inadequate surface passivation process. With regard to the other two traps, the electrical stress increases the trap density of DP2 and causes the emergence of DP3 as one new trap. These results may be useful in the design and application of AlGaN/GaN HEMTs. These results may be useful in the design and application of AlGaN/GaN HEMTs.

Background and aimsCurrent practice on Helicobacter pyloriinfection mostly focuses on individual-based care in the community, but family-based H. pylorimanagement has recently been suggested as a better strategy for infection control. However, the family-based H. pyloriinfection status, risk factors and transmission pattern remain to be elucidated.MethodsFrom September 2021 to December 2021, 10 735 families (31 098 individuals) were enrolled from 29 of 31 provinces in mainland China to examine family-based H. pyloriinfection, related factors and transmission pattern. All family members were required to answer questionnaires and test for H. pyloriinfection.ResultsAmong all participants, the average individual-based H. pyloriinfection rate was 40.66%, with 43.45% for adults and 20.55% for children and adolescents. Family-based infection rates ranged from 50.27% to 85.06% among the 29 provinces, with an average rate of 71.21%. In 28.87% (3099/10 735) of enrolled families, there were no infections; the remaining 71.13% (7636/10 735) of families had 1–7 infected members, and in 19.70% (1504/7636), all members were infected. Among 7961 enrolled couples, 33.21% had no infection, but in 22.99%, both were infected. Childhood infection was significantly associated with parental infection. Independent risk factors for household infection were infected family members (eg, five infected members: OR 2.72, 95% CI 1.86 to 4.00), living in highly infected areas (eg, northwest China: OR 1.83, 95% CI 1.57 to 2.13), and large families in a household (eg, family of three: OR 1.97, 95% CI 1.76 to 2.21). However, family members with higher education and income levels (OR 0.85, 95% CI 0.79 to 0.91), using serving spoons or chopsticks, more generations in a household (eg, three generations: OR 0.79, 95% CI 0.68 to 0.92), and who were younger (OR 0.57, 95% CI 0.46 to 0.70) had lower infection rates (p<0.05).ConclusionFamilial H. pyloriinfection rate is high in general household in China. Exposure to infected family members is likely the major source of its spread. These results provide supporting evidence for the strategic changes from H. pyloriindividual-based treatment to family-based management, and the notion has important clinical and public health implications for infection control and related disease prevention.

Potassium ions are widely involved in a series of physiological and biochemical processes of plants, which is of great significance to plant growth. High-affinity K+(HAK) transporter mainly absorbed and transported potassium in plants, but there are few studies on HAKgene in sugarcane. In this study, the coding region of high-affinity K+transporter genes were cloned from sugarcane and designated as ScHAK9, ScHAK10, ScHAK11(GenBank accession number: MG564720, MG564721, MG564722). Phylogenetic analysis results confirmed that ScHAK9and ScHAK11had the closest relationship with ZmHAK9and ZmHAK11(Zea mays), ScHAK10had the closest relationship with SbHAK10(Sorghum bicolor). In subcellular localization experiments, the fusion protein of ScHAK9 and ScHAK11 with green fluorescent protein was specifically localized in the cell membrane, but ScHAK10 green fluorescent protein was not detected, it was speculated to be expressed in Golgi apparatus. The gene expression level of ScHAKin different tissues of sugarcane at the growth periods was different, and the gene expression level of ScHAKgenes were up-regulated by the low-potassium and salt stress. Through the functional characterization experiments of ScHAKgenes in K+uptake-deficient yeasts, it was founded that ScHAKgenes possessed K+transporter activity. The study indicated that ScHAKgenes might mediate K+absorption through the cell membrane and might be participate in maintaining Na+/K+homeostasis in sugarcane under the adversity stress, and the development of plant organs is regulated by the potassium ions transport of ScHAKgenes.

Paraffin waxes (PW) are organic phase change materials (PCMs) that can be potentially applied for the storage/release of low-temperature latent heat and thermal management. However, they have serious liquid leakage and poor thermal conductivity, which greatly restrict their practical application. Although numerous studies have been conducted to address these problems, it is challenging to achieve phase change composites (PCCs) that are characterized by high thermal conductivity and excellent phase change behavior. Herein, we put forward a novel strategy for preparing expanded graphite (EG)/PW binary PCCs with EG loading varying in the range of 10–40 wt%. The method is developed by constructing graphite sheets with high orientation inside the PCCs following compression induction. The highly oriented graphite sheets provide channels for highly efficient heat transfer, which significantly improves the thermal conductivity of the resulting EG/PW PCCs. The in-plane thermal conductivities of the EG/PW PCCs are in the range of 10.7–49.7 W m−1 K−1under 10–40 wt% EG loading conditions, much larger than those of the previously reported EG/PW PCCs with the same EG content. The EG/PW composites also exhibit excellent compatibility, uniformity, thermostability, reliability, and phase change behaviors. These remarkable properties make the EG/PW composites promising for application in thermal management and heat storage. This work provides an efficient and generic strategy for designing and constructing high-efficiency heat transfer channels within the PCCs using sheet-shaped fillers with high thermal conductivity.

In the distributed machine learning field, federated learning (FL) serves as a highly effective framework for dismantling data silos and integrating data from multiple sources. However, the flourishing of FL still encounters significant challenges, particularly in the realms of data security and information privacy. In recent years, plenty of privacy-preserving FL schemes have been proposed, yet few of them support global model confidentiality protection for the training server. In this paper, by combining Trusted Execution Environment (TEE) and homomorphic encryption, we propose a TEE-assisted federated logistic regression training scheme with model confidentiality protection, named TFLR. Specifically, we first formalize a cryptography-TEE hybrid security model under the multi-party cooperative computation scenario. Subsequently, within this hybrid security model, we design a series of secure computation protocols with semi-honest TEE to execute non-linear operations while maintaining the encryption form of global model parameters. Therefore, the global model of the training server can be well protected. In addition, TFLR incorporates a double masking technique, further fortifying the privacy of data owners' local updates. Detailed security analysis shows that TFLR is able to protect all sensitive information of data owners and the training server. Furthermore, we evaluate the performance of TFLR with real machine learning datasets, and the results substantiate that TFLR is indeed efficient. • A fine-grained Cryptography-TEE hybrid security model for multi-party cooperative computation scenario is defined. • A series of TEE-assisted secure computation protocols are designed to achieve secure and lossless non-linear operations. • A federated logistic regression training scheme with model confidentiality protection is constructed. • The efficiency of the proposed scheme is much higher than polynomial or alternative approximation based schemes. [ABSTRACT FROM AUTHOR]

Federated learning (FL), as a distributed machine learning paradigm, essentially promises that multiple parties can jointly train the model collaboratively without sharing local data. Recent research demonstrates that the adversary can deduce the sensitive data through shared model updates. To protect the data privacy of the participants, differential privacy (DP) is deployed in various FL scenarios due to the lightweight computational overhead. However, the trade-off between the availability and privacy of local models is the fundamental problem that needs to be solved in DP applications. In this paper, we propose a fine-grained and privacy-aware FL framework (iDP-FL) to enable training data and model parameters to satisfy confidentiality while markedly improving the model's prediction accuracy. Specifically, we first design an individualized perturbation noise (IPN) algorithm that adds different artificial noises dependent on the importance of each participant's model weight. Then, we propose a perturbation mechanism on the aggregator side, a DP protection method under the premise of loss function convergence, which prevents the global model parameters from being stolen by malicious adversaries. Moreover, to achieve lightweight protection throughout the learning, we present an advanced bilateral perturbation (ABP) protocol to perform iterative training. Theoretical analysis indicates that iDP-FL provides the DP guarantee, which yields superior prediction accuracy and excellent privacy-preserving with the same privacy level. Finally, extensive experiments conducted on real-world datasets demonstrate that our approach shows significant advantages with limited privacy budgets, especially at small privacy losses. [ABSTRACT FROM AUTHOR]

We developed an in situcoordination-driven spatially confined strategy for preparing near-infrared emissive gold nanoclusters encapsulated by fluorinated polymers (AuNCs@PF, λmax= 810 nm) with good stability and high quantum yields (27.7%), far higher than those previously reported for NIR AuNCs (>800 nm). Based on the stepwise enhancements including long blood circulation-induced passive tumor targeting, fluoro-enhanced tumor permeation, and tumor microenvironment (weak acid)-induced aggregation retention in cells, these AuNCs demonstrated bright and stable NIR fluorescence imaging ability in tumors. Additionally, the AuNCs@PF were capable of fluorine magnetic resonance imaging and computed tomographic imaging. The multimodal imaging of tumor-bearing mice clearly implied the potential of AuNCs@PF in biomedical fields.

The WE43 magnesium alloy was prepared by squeeze casting, and the influence of squeeze casting parameters on mechanical properties and corrosion resistance was studied and compared with gravity casting. The gravity cast WE43 alloy shows uneven grain size distribution, and some grains even greater than 90 µm. While, the grain size of the squeeze cast WE43 alloy is mainly distributed in 20–50 µm. The Mg12Nd2Y phase morphology changes from large lamellar to strips after squeeze casting, whereas Mg24Y5phase exhibits no obvious change. The yield strength, tensile strength, and elongation of the gravity cast WE43 alloy are 127 MPa, 157 MPa, and 6%, respectively, and 145 MPa, 193 MPa, and 9.1% for squeeze cast alloy. For the squeeze cast WE43 alloy, the average corrosion rate is 0.6056 mm·year−1according to immersion test results, and according to electrochemical measurements, the corrosion current density is 78.13 µA·cm−2, which is better than that of the gravity cast WE43 alloy. Compared with gravity casting, the grains and second phase of the WE43 alloy by squeeze casting are refined, and the mechanical properties and corrosion resistance are improved. This may expand the applications of the WE43 alloy.

It is undeniable that Internet of Things (IoT) in big data era can provide us with huge volumes of multi-dimensional data, transforming our society into a much more intelligent one. In order to fit for the multi-dimensional data processing in big data era, multi-dimensional range queries, especially over cloud platform, have received considerable attention in recent years. However, as the cloud server is not fully trustable, designing multi-dimensional range queries over encrypted data becomes a research trend, and many solutions have been proposed in the literature. Nevertheless, most existing solutions suffer from the leakage of the single-dimensional privacy, and such leakage would severely put the data at risk. Although a few existing works have addressed the problem of single-dimensional privacy, they are impractical in some real scenarios due to the issues of inefficiency, inaccuracy, and two-cloud-server requirement. Aiming at solving these issues, in this article, we propose a practical and privacy-preserving multi-dimensional range query (PRQ) scheme. Specifically, in our proposed PRQ scheme, we first index the multi-dimensional dataset with an R-tree and reduce R-tree based range queries to the problem of point intersection and range intersection. Then, by employing the lightweight matrix encryption technique, we design two novel algorithms for PRQ, i.e., multi-dimensional point intersection predicate encryption (PIPE) and multi-dimensional range intersection predicate encryption (RIPE), which can preserve the privacy of the proposed point intersection algorithm and range intersection algorithm, and further preserve the single-dimensional privacy of the proposed PRQ scheme. Detailed security analysis shows that our proposed PRQ scheme is indeed privacy-preserving. In addition, extensive simulations are conducted, and the results also demonstrate its efficiency.

ABSTRACTThis study examines the acculturation characteristics of Chinese students in the context of a multicultural classroom. The Chinese yin-yang philosophy is used to provide another dimension of interpretation and analysis in addition to Berry's acculturation strategy framework. Qualitative data over a five-year period reveal their changing psychological states in a multicultural classroom. Four stages of acculturation were identified: initial, contact, reflection, and change. At each stage, Chinese students dynamically react and change in the acculturation process, which is similar to the intertwining process of yinand yang, a metaphorical image seen in the Chinese yin-yang philosophy.