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Free flap reconstruction for postoperative tissue defects in oral and maxillofacial tumors is a critical component of reconstructive surgery. Identifying risk factors for flap necrosis is essential for improving surgical outcomes and patient quality of life. A retrospective study was conducted on patients who underwent free flap reconstruction between January 2020 and December 2023. Patients were included if they had comprehensive medical records and at least a six-month follow-up. We excluded those with a history of flap necrosis, uncontrolled systemic diseases, non-adherence to postoperative care, or concurrent malignancy treatments. Data on demographics, comorbidities, flap characteristics, and operative details were collected and analyzed using univariate analysis and logistic regression tests. Univariate analysis did not find a significant correlation between flap necrosis and factors such as hyperlipidemia, lymph node metastasis, or flap type. However, diabetes mellitus, oral infections, and albumin levels below 35 g/L were significantly associated with flap necrosis. Multivariate logistic regression showed diabetes mellitus increased the odds of flap necrosis by approximately ninefold, and oral infection increased it by over tenfold. Diabetes mellitus, oral infection, and low albumin levels are significant risk factors for flap necrosis in free flap reconstruction after oral and maxillofacial surgery. Prompt identification and management of these factors are crucial to mitigate the risk of flap necrosis. [ABSTRACT FROM AUTHOR]

In this Letter, an enhancement mode (E-mode) β-Ga2O3 metal-oxide-semiconductor field-effect transistor (MOSFET) with quasi-two-dimensional channel was reported, and the channel mobility of 147.5 cm2/(V·s) is achieved. Low damage etching technology and low Ohmic contact resistance technology are introduced. As a result, the E-mode transistor demonstrates a maximum drain to source current (ID) of 230.5 mA/mm, a peak transconductance (Gm) of 54.2 mS/mm, a current gain cut-off frequency (fT) of 18 GHz, and a power gain cut-off frequency (fMAX) of 42 GHz. Additionally, a positive threshold voltage (VT) of 1.65 V, a breakdown voltage (VBK) of 420 V, and a specific on-resistance (RON,SP) of 1.24 mΩ·cm2 are achieved. Moreover, a fMAX × VBK of 17.64 THz·V and a fT × VBK of 7.56 THz·V are found to be a close value so far to the theoretical limit of β-Ga2O3. This device leads to excellent radio frequency (RF) characteristics, which paved the way for future millimeter-wave RF power electronics applications with β-Ga2O3 MOSFET. [ABSTRACT FROM AUTHOR]

This Letter reports two kinds of oxygen-containing plasma treated β-Ga2O3 Schottky barrier diodes (SBDs), including N2O plasma treatment and O2 plasma treatment, and the SBD without plasma is prepared for comparison. I–V characteristics, breakdown characteristics, and trap state characteristics of three devices have been studied. It is found that the turn-on voltage of SBDs with N2O plasma can reduce to 0.6 V, and the better current density of 750 A/cm2 and an on-resistance of 3.5 mΩ cm2 are obtained after the N2O plasma treatment. Moreover, the breakdown voltage of SBDs with N2O plasma is 50.2% higher than the conventional one, whose value reaches 323 V. In addition, the trap states' characteristics of the devices are studied, which show that the oxygen-containing plasma can reduce the deep level trap states density partly in the anode region, which can improve the surface quality effectively. [ABSTRACT FROM AUTHOR]

A β-Ga2O3 Schottky barrier diode (SBD) with a p-type NiOx guard ring was fabricated, and the reverse leakage and subthreshold leakage current reduction was found at high temperatures from temperature-dependent I–V characteristics. The functional mechanisms of NiOx as edge termination on leakage reduction were studied. NiOx can increase the barrier height and passivate the defects at the interface, resulting in the suppression of subthreshold leakage and elimination of current crowding effect confirmed by a thermal emission microscope. From the temperature-dependent x-ray photoelectron spectroscopy characteristics, more holes generated to deplete Ga2O3 at higher temperatures were found. It leads to reduce the reverse leakage current. The small-polaron transportation in NiOx is proposed to argue the implausibility of the leakage conduction in NiOx. This work will offer critical physical insight and a valuable route for developing low-leakage Ga2O3 SBDs. [ABSTRACT FROM AUTHOR]

In the bridge maintenance management decision, the health evaluation on bridge structure is far more than determination of abnormal index exceed fixed threshold, or evaluation on damage status and carrying capacity, the on-site human inspection should also be paid attention. In order to achieve more accurate and reliable health status evaluation result, it needs to take full advantage of various information and parameter. The D-S evidence information fusion was used in the paper to present comprehensive bridge health evaluation method. It fuses bridge operation status using abnormal status identification, bridge durability with residual life estimation, as well as human inspection rating, to arrive at health evaluation. The actual application examples to verify the method is also provided.

The bridge structure abnormality recognition is one of the key steps of its health assessment. Using novelty detection technique based on BP neural network, the method to identify and locate abnormal bridge status was presented. It uses non-training-data in the original sample data to generate novelty indicator and determines threshold. If the difference between detection status indicator and normal value is larger than the threshold, the structure status is determined changed. The method adapts stepwise partition identification method. The method firstly determines damage position within a small range and then analyzes sensor data in detail, so as to locate specific position. The measured data on T beam model verifies the method can accurately carry out status identification and locate cracking position under cracking load conditions.

A low temperature controlled annealing technique was utilized to improve the performance of vertical β-gallium oxide (β-Ga2O3) Schottky barrier diodes (SBDs) in this work. The nickel is diffused into Ga2O3, and NiO was formed at the interface between the anode and semiconductor generating p–n junction after low temperature annealing. Simultaneously, the trap state density of interface Ni/Ga2O3 as well as the carbon bonded with oxygen on the surface was reduced, which was proved by the capacitance and conductance measurements and x-ray photoelectron spectroscopic analysis, respectively. Combined the decreased saturation current density by three orders of magnitude from 1.21 × 10−6 to 9.27 × 10−8 and 5.12 × 10−9 A/cm2 and larger breakdown voltage from 220 to 270 V owing to the optimized interface and the formation of NiO, a low temperature annealing technique makes certain effective improvement for vertical β-Ga2O3 SBDs via interface engineering. [ABSTRACT FROM AUTHOR]

PbZr0.2Ti0.8O3 (PZT) gate insulator with the thickness of 30 nm is grown by pulsed laser deposition (PLD) in AlGaN/GaN metal–insulator–semiconductor high electron mobility transistors (MIS-HEMTs). The ferroelectric effect of PZT AlGaN/GaN MIS-HEMT is demonstrated. The polarization charge in PZT varies with different gate voltages. The equivalent polarization charge model (EPCM) is proposed for calculating the polarization charge and the concentration of two-dimensional electron gas (2DEG). The threshold voltage (Vth) and output current density (IDS) can also be obtained by the EPCM. The theoretical values are in good agreement with the experimental results and the model can provide a guide for the design of the PZT MIS-HEMT. The polarization charges of PZT can be modulated by different gate-voltage stresses and the Vth has a regulation range of 4.0 V. The polarization charge changes after the stress of gate voltage for several seconds. When the gate voltage is stable or changes at high frequency, the output characteristics and the current collapse of the device remain stable. [ABSTRACT FROM AUTHOR]

The construction of highway ecological landscape is an important part of highway entity and an iconic feature of scenic countryside and ecological garden city, which plays an important role in the process of achieving social and economic sustainable development. The efficient index system and method is a basic measurement for the assessment of the interior quality and its associated outer environment. By taking five arterial highways (G15, G228, G204, S334 and S335) in the territory of Nantong City, Jiangsu Province as the case, an evaluation system containing quantitative and qualitative indices was developed to deal with the ecological landscape quality. The system composed of 12 evaluation indices which were divided into three categories including ornamental value, ecological efficiency, and safety design. Based on the survey and calculation of the raw data, the variable matrix was established and analyzed with principal component (PC) analysis. The results showed that the equation of highway greening ecological evaluation score was H = 0.694xPCl +0.191 XPC2+0.115XPC3, and scores of 5 highways ranked in the ordination of G204 > G15 > S334 > G228 > S335. The results would provide methods and references for efficient evaluation of highway landscape. [ABSTRACT FROM AUTHOR]

Background: His bundle pacing (HBP) and left bundle branch pacing (LBBP) both provide physiologic pacing which maintain left ventricular synchrony. They both improve heart failure (HF) symptoms in atrial fibrillation (AF) patients. We aimed to assess the intra-patient comparison of ventricular function and remodeling as well as leads parameters corresponding to two pacing modalities in AF patients referred for pacing in intermediate term., Methods: Uncontrolled tachycardia AF patients with both leads implantation successfully were randomized to either modality. Echocardiographic measurements, New York Heart Association (NYHA) classification, quality-of-life assessments and leads parameters were obtained at baseline and at each 6-month follow up. Left ventricular function including the left ventricular endo-systolic volume (LVESV), left ventricular ejection fraction (LVEF) and right ventricular (RV) function quantified by tricuspid annular plane systolic excursion (TAPSE) were all assessed., Results: Consecutively twenty-eight patients implanted with both HBP and LBBP leads successfully were enrolled (69.1 ± 8.1 years, 53.6% male, LVEF 59.2% ± 13.7%). The LVESV was improved by both pacing modalities in all patients ( n = 23) and the LVEF was improved in patients with baseline LVEF at less than 50% ( n = 6). The TAPSE was improved by HBP but not LBBP ( n = 23)., Conclusion: In this crossover comparison between HBP and LBBP, LBBP was found to have an equivalent effect on LV function and remodeling but better and more stable parameters in AF patients with uncontrolled ventricular rates referred for atrioventricular node (AVN) ablation. HBP could be preferred in patients with reduced TAPSE at baseline rather than LBBP., (© 2023 JGC All rights reserved; www.jgc301.com.)

In order to assess the pollution of polycyclic aromatic hydrocarbons(PAHs) in a suburban farmland soil, 29 sampling sites were collected around Nanjing according to the grid method, and the contents of 15 different PAHs were determined. Acenaphthene(Ace) was not detected in any of the samples. The total content of PAHs in farmland soil ranged from 24.49 to 750.04 μg·kg -1 , with an average of 226.64 μg·kg -1 . The spatial distribution of high-ring PAHs, the main PAHs in the farmland soil, was similar to that of total PAHs. There was no significant correlation between PAHs and soil organic matter(SOM), pH, cation exchange capacity(CEC), and total nitrogen(TN), whereas bulk density and low ring PAHs were significantly correlated. The results of source apportionment show that the main source of PAHs in the farmland soil is a mixture of combustion and petroleum. The contamination severity index(CSI) index shows that the PAHs does not pose an ecological risk. The results of the health risk assessment show that there is no potential carcinogenic risk to children or adults, and the main sequence of exposure is skin contact>ingestion>inhalation.

Aim: The underlying mechanisms of chemoresistance-induced recurrence of ovarian carcinoma are largely unknown. The purpose of this study was to investigate the clinical significance of RAD51C and its role in ovarian tumorigenesis and progression., Methods: 60 cases of ovarian epithelial tumors (30 benign and 30 malignant tumors, respectively) were enrolled from 2014 to 2016. Immunohistochemistry was used to evaluate RAD51C expression in tumor tissues, and RT-PCR was employed to test RAD51C mRNA levels in SKOV3, A2780, and CAOV3 cell lines. Targeted knockdown of RAD51C was achieved with siRNA to explore the changes of cell proliferation, migration, and apoptosis., Results: RAD51C protein level in carcinoma tissues, especially in the high-grade group (P<0.001), was significantly higher than that of benign tumors and associated with pathological type, stage, and overall survival (P<0.05). Downregulation of RAD51C promoted apoptosis and decreased cell survival rate and migration., Conclusions: Our results supported that RAD51C contributes to the progression of ovarian carcinoma, suggesting its promising application as an independent prognostic marker for diagnosis and treatment., Competing Interests: None., (IJCEP Copyright © 2020.)

Aim: To examine the therapeutic effects of tocilizumab on experimental corneal transplantation and its effect on Treg/Th17 balance., Methods: Allograft corneal graft was performed between host Sprague Dawley and Wistar donor rats. The rats were randomly divided into four groups: normal, autograft, allograft, and allograft treated with tocilizumab. Kaplan-Meier was performed to draw the survival curve. The protein levels of interleukin-17A (IL-17A), vascular endothelial growth factor (VEGF), and forkhead box protein 3 (Foxp3) were measured by immunohistochemistry. The mRNA levels of IL-17A, VEGF, retinoid-related orphan receptor gammat (RORγt), interleukin-6 (IL-6) and Foxp3 were detected by reverse transcription real-time polymerase chain reaction (RT-PCR). The Treg and Th17 cells were investigated by flow cytometry., Results: The survival time of tocilizumab group was (24±1.27d) longer than that of allograft group (10±0.55d). Moreover, immunohistochemical examination revealed that IL-17A and VEGF protein levels in the allograft group were significantly higher than that of tocilizumab group ( P <0.01), while Foxp3 levels in the allograft group was significantly lower than that of the tocilizumab treated group ( P <0.001). Flow cytometry showed that the number of Th17 cells in allograft group was significantly higher than that in tocilizumab group ( P <0.001). Meanwhile, the number of Tregs was significantly lower than in tocilizumab group ( P <0.001). Simultaneously, Foxp3 mRNA expression level in corneal tissues of tocilizumab treated group was significantly higher than other groups ( P <0.001)., Conclusion: These findings suggest that tocilizumab may promote corneal allograft survival, possibly by modulating Treg-Th17 balance., (International Journal of Ophthalmology Press.)

The construction of highway ecological landscape is an important part of highway entity and an iconic feature of scenic countryside and ecological garden city, which plays an important role in the process of achieving social and economic sustainable development. The efficient index system and method is a basic measurement for the assessment of the interior quality and its associated outer environment. By taking five arterial highways (G15, G228, G204, S334 and S335) in the territory of Nantong City, Jiangsu Province as the case, an evaluation system containing quantitative and qualitative indices was developed to deal with the ecological landscape quality. The system composed of 12 evaluation indices which were divided into three categories including ornamental value, ecological efficiency, and safety design. Based on the survey and calculation of the raw data, the variable matrix was established and analyzed with principal component (PC) analysis. The results showed that the equation of highway greening ecological evaluation score was H=0.694&times;PC1+0.191&times;PC2+0.115&times;PC3, and scores of 5 highways ranked in the ordination of G204 > G15 > S334 > G228 > S335. The results would provide methods and references for efficient evaluation of highway landscape.

Purpose: To study the biocompatibility of a new polylactic acid-glycolic acid(PLGA)/fish skin collagen conjugated electrostatic spinning film., Methods: PLGA and medical-grade fish skin-I collagen were used as raw materials to prepare nanometer fiber films by conjugated electrostatic spinning technique. Mouse fibroblast L929 was used as a model to evaluate its cell and histocompatibility, which provided experimental basis for application in guided bone regeneration (GBR)., Results: Fibroblasts showed good adhesion and growth on the surface of fiber membrane; there were a large number of deep pseudopodias, which were arranged along the orientation of fibers., Conclusions: PLGA/fish skin collagen conjugated electrostatic spinning membrane is beneficial to fibroblast growth and is expected to be used for GBR.