Search Results (52)

A series of problems, such as material damage and charge trap, can be caused when GaN HEMT power devices are subjected to high field stress in the off-state. The reliability of GaN HEMT power devices affects the safe operation of the entire power electronic system and seriously threatens the stability of the equipment. Therefore, it is particularly important to study the damage mechanism of GaN HEMT power devices under high field conditions. This work studies the degradation of Cascode GaN HEMT power devices under off-state high-field stress and analyzes the related damage mechanism. It is found that the high field stress in the off-state will generate a positive charge trap in the oxide layer of the MOS device in the cascade structure. Moreover, defects occur in the barrier layer and buffer layer of GaN HEMT devices, and the threshold voltage of Cascode GaN HEMT power devices is negatively shifted, and the transconductance is reduced. This study provides an important theoretical basis for the reliability of GaN HEMT power devices in complex and harsh environments. Full article

Background: In non-metastatic deficient mismatch repair (dMMR) colorectal cancer (CRC), traditional prognostic factors, such as pN staging, often fail to distinguish patient outcomes effectively. Methods: This retrospective study included a cohort of 792 dMMR CRC patients who underwent surgical treatment without neoadjuvant chemoradiotherapy or immunotherapy. Traditional prognostic factors were compared with lymph node-based models (NLN, LNR, LOODS) for their ability to predict overall survival (OS) and disease-free survival (DFS). Results: The study demonstrated that traditional factors, such as histologic type, differentiation, and vascular invasion, had limited predictive value in dMMR CRC. Furthermore, the pN stage failed to effectively distinguish between pN1 and pN2 for both OS (p = 0.219) and DFS (p = 0.095). Conversely, LOODS demonstrated superior performance over traditional pN staging in predicting both OS and DFS (p < 0.001). A prognostic model combining LOODS with age exhibited superior predictive performance compared with the traditional TN staging system. Conclusions: LOODS was identified as a more effective independent prognostic factor compared with traditional pN staging, enabling more precise stratification of pN+ patients in non-metastatic dMMR CRC, highlighting its potential utility in guiding postoperative treatment and optimizing therapeutic strategies. Full article

Background: Rice bacterial leaf blight, caused by the Gram-negative bacterium Xanthomonas oryzae pv. Oryzae (Xoo), significantly impacts rice production. To address this disease, research efforts have focused on discovering and utilizing novel disease-resistant genes and examining their functional mechanisms. Methods and Results: In this study, a variety of bacterial strains were utilized. CX28-3, AX-11, JC12-2, and X10 were isolated from the high-altitude japonica rice-growing region on the Yunnan Plateau. Additionally, PXO61, PXO86, PXO99, and PXO339, sourced from the International Rice Research Institute (IRRI), were included in the analysis. To evaluate the resistance characteristics of Haonuoyang, artificial leaf cutting and inoculation methods were applied. Results indicated that Haonuoyang exhibited broad-spectrum resistance. Additionally, to explore the genetic mechanisms of resistance, the TFAIII-type transcription factor OsZFPH was cloned from Haonuoyang using PCR amplification. The subcellular localization method identified the precise location of the OsZFPH gene within the cell. The expression of OsZFPH was induced by Xoo stress. The overexpression of OsZFPH resulted in increased activities of enzymes, including SOD, CAT, and POD, while silencing the gene led to reduced enzyme activities. Furthermore, the hormones SA (salicylic acid), JA (jasmonic acid), and GA (gibberellin) were shown to positively regulate the gene expression. Protein interactions with OsZFPH were verified through a yeast two-hybrid system and BiFC technology. Hap5, which aligned with the sequence of Haonuoyang, was found to belong to a haplotype consisting of Jingang 30, 40 resequenced rice varieties, 18 Oryza rufipogon, and 29 Oryza granulata. Conclusions: The findings of this study emphasize the vital role of OsZFPH in rice resistance to bacterial leaf blight. The identification of broad-spectrum resistance in Haonuoyang and the understanding of OsZFPH gene functions provide valuable insights for the future development of rice varieties with improved resistance to this destructive disease. Full article

The serious impact of Alternaria alternata on jujube black spot disease has seriously affected the quality and yield of jujube, constraining the sustainable development of the jujube industry. The purpose of this study was to isolate and screen highly effective biocontrol strains of jujube black spot disease from jujube rhizosphere soil. Thirty-three soil samples were collected from four regions in southern Xinjiang. The strains with antagonistic effects were isolated and screened by the dilution spread method and plate confrontation method and identified by morphological, physiological, and biochemical characteristics, as well as 16S rDNA, gyrB, and rpoB gene sequences. Indoor and field efficacy experiments were conducted to determine their biocontrol effect. A total of 110 strains with antibacterial activity were selected, and one strain, Bacillus velezensis 26-8, with a stable antagonistic effect was further tested. Biological characteristic experiments showed that strain 26-8 could grow at NaCl concentrations of 0.5–10% and pH 4.0–9.0. The biocontrol experiment results showed that Bacillus velezensis 26-8 could achieve an 89.83% control effect against black spot disease. In conclusion, strain 26-8 has good salt and alkali tolerance, exerts a good control effect on jujube black spot disease, and is worthy of further study. Full article

The large-scale storage and stable supply of oil products are essential for national energy security and economic development. As the economy expands and energy demands rise, centralized storage and supply systems become increasingly vital for ensuring the efficiency and reliability of oil product distribution. However, large oil storage depots present substantial safety risks. In the event of fires, explosions, or other accidents, emergency response efforts face stringent demands and challenges. To enhance the emergency response capabilities of oil storage and transportation bases (OSTBs), this paper proposes an innovative approach that integrates the improved analytic hierarchy process (IAHP) with the Entropy Weight Method (EMW) to determine the combined weights of various indices. This approach reduces the subjective bias associated with the traditional analytic hierarchy process (AHP). The emergency response capabilities of OSTBs are subsequently evaluated through fuzzy comprehensive analysis. An empirical study conducted on an OSTB in the Zhoushan archipelago quantitatively assesses its emergency preparedness. The results show that the base excels in pre-incident prevention, demonstrates robust preparedness and response capabilities, and exhibits moderate recovery abilities after incidents. These findings provide a theoretical foundation for reducing the likelihood of accidents, enhancing emergency response efficiency, and mitigating the severity of consequences. Practical recommendations are also offered based on the results. Full article

GaN HEMT devices are sensitive to the single event effect (SEE) caused by heavy ions, and their reliability affects the safe use of space equipment. In this work, a Ge ion (LET = 37 MeV·cm²/mg) and Bi ion (LET = 98 MeV·cm²/mg) were used to irradiate Cascode GaN power devices by heavy ion accelerator experimental device. The differences of SEE under three conditions: pre-applied electrical stress, different LET values, and gate voltages are studied, and the related damage mechanism is discussed. The experimental results show that the pre-application of electrical stress before radiation leads to an electron de-trapping effect, generating defects within the GaN device. These defects will assist in charge collection so that the drain leakage current of the device will be enhanced. The higher the LET value, the more electron–hole pairs are ionized. Therefore, the charge collected by the drain increases, and the burn-out voltage advances. In the off state, the more negative the gate voltage, the higher the drain voltage of the GaN HEMT device, and the more serious the back-channel effect. This study provides an important theoretical basis for the reliability of GaN power devices in radiation environments. Full article

Drainage pipes are often positioned downstream of embankments to mitigate pore pressure, thereby reducing the risk of dam failure. Considering that the size of drainage pipes is much smaller than that of embankment dams, directly discretizing the drainage pipes will generate a huge number of elements. Therefore, this paper proposes a seepage element containing drainage pipes. In this element, the permeability of the drainage pipe is taken as the third type of permeable conductivity condition, and it is considered in the energy functional. The governing equations for the steady-state and the transient seepage element containing drainage pipe are derived using the variational principle, and the infiltration matrix, equivalent nodal seepage array, and water storage matrix of the seepage element containing drainage pipe are obtained. In conjunction with the user-defined element module UEL of ABAQUS 2016 software, the established seepage element containing drainage pipe is programmed. The accuracy and efficiency of the proposed seepage element containing drainage pipe are verified through seepage field simulations of three examples. Finally, the influence of the permeable conductivity of drainage pipes on the pressure reduction effect is investigated, providing a reference for the layout of drainage pipes in embankment defense systems. Full article

Recent interest in preventing the development of osteoporosis has focused on the regulation of redox homeostasis. However, the action of lycopene (LYC), a strong natural antioxidant compound, on osteoporotic bone loss remains largely unknown. Here, we show that oral administration of LYC to OVX rats for 12 weeks reduced body weight gain, improved lipid metabolism, and preserved bone quality. In addition, LYC treatment inhibited ROS overgeneration in serum and bone marrow in OVX rats, and in BMSCs upon H₂O₂ stimulation, leading to inhibiting adipogenesis and promoting osteogenesis during bone remodeling. At the molecular level, LYC improved bone quality via an increase in the expressions of FoxO1 and Runx2 and a decrease in the expressions of PPARγ and C/EBPα in OVX rats and BMSCs. Collectively, these findings suggest that LYC attenuates osteoporotic bone loss through promoting osteogenesis and inhibiting adipogenesis via regulation of the FoxO1/PPARγ pathway driven by oxidative stress, presenting a novel strategy for osteoporosis management. Full article

Air DTH (Down-The-Hole) hammer percussion drilling (vibration percussion drilling) has proven to be a highly efficient geothermal drilling technique, and percussion fractures near the wellbore benefit geothermal energy development in many ways (such as hydraulic fracturing, perforation, etc.). However, no research has been done on the mechanism of fracture-increasing and permeation-increasing in granite pore walls by air DTH hammer percussion drilling. This article: (1) using an air drilling test device, an air DTH hammer whole bit impact rock fragmentation test was conducted on granite in an atmospheric environment; (2) dyeing experiments, CT scanning, and 3D reconstruction modeling were used to characterize and identify wellbore cracks; (3) research the strength, porosity, and permeability changes of granite wellbore through mechanical and permeability testing experiments; and (4) numerical simulation of impact stress waves using particle flow code (PFC) 6.0 software to demonstrate the rationality of impact experimental results. The results show that the air DTH hammer impact can induce micro-cracks in the wellbore, and the distribution of cracks is regionalized, mainly due to the attenuation of the impact stress wave. The numerical results are consistent with the experimental results. The average strength of granite decreased by 16.5%, the average porosity increased by 9.5%, the average permeability increased by 63.3%, the porosity increased from 0.0025% to 0.03%, and the porosity increased by about 12 times under the air DTH Hammer percussion drilling. The above results provide the theoretical basis and experimental proof for the ability of air DTH hammer drilling to produce wellbore cracks and improve wellbore permeability. The presented experimental results can be a useful reference for building numerical models. Full article

Self-powered photodetectors have the advantages of high sensitivity, sustainability, and small size and have become a research hotspot in advanced optoelectronic systems. However, the low output photocurrent density seriously hinders the practical application of ferroelectric self-powered photodetectors. Herein, the high-efficiency photoelectric detection performance of the Bi_1-xHo_xFeO₃ ferroelectric self-powered photodetector is realized by doping Ho. The responsivity (R) and detectivity (${\mathrm{D}}^{\mathrm{*}}$) can reach 0.0159 A/W and 1.94 × 10¹¹ Jones under monochromatic light with a wavelength of 900 nm. Meanwhile, the R and ${\mathrm{D}}^{\mathrm{*}}$ can reach 0.022 A/W and 2.65 × 10¹¹ Jones under sunlight. These excellent photodetection performances are attributed to the high short-circuit current density (J_sc). When the Ho content is 6%, the output photocurrent reaches up to 0.81 mA/cm². The systematic structure and photo-electric characteristic analysis suggest that the decrease in the band gap leads to the generation of a larger photocurrent while the ferroelectric polarization is reduced slightly. This work provides a new way to obtain high-performance self-powered photodetectors. Full article

One of the challenges of using Time-of-Flight (ToF) sensors for dimensioning objects is that the depth information suffers from issues such as low resolution, self-occlusions, noise, and multipath interference, which distort the shape and size of objects. In this work, we successfully apply a superquadric fitting framework for dimensioning cuboid and cylindrical objects from point cloud data generated using a ToF sensor. Our work demonstrates that an average error of less than 1 cm is possible for a box with the largest dimension of about 30 cm and a cylinder with the largest dimension of about 20 cm that are each placed 1.5 m from a ToF sensor. We also quantify the performance of dimensioning objects using various object orientations, ground plane surfaces, and model fitting methods. For cuboid objects, our results show that the proposed superquadric fitting framework is able to achieve absolute dimensioning errors between 4% and 9% using the bounding technique and between 8% and 15% using the mirroring technique across all tested surfaces. For cylindrical objects, our results show that the proposed superquadric fitting framework is able to achieve absolute dimensioning errors between 2.97% and 6.61% when the object is in a horizontal orientation and between 8.01% and 13.13% when the object is in a vertical orientation using the bounding technique across all tested surfaces. Full article

A GaN high-electron-mobility transistor (HEMT) was simulated using the semiconductor simulation software Silvaco TCAD in this paper. By constructing a two-dimensional structure of GaN HEMT, combined with key models such as carrier mobility, the effects of a different state, different incidence position, different drain voltage, different LET values, and a different incidence angle on the single-event transient effect of GaN HEMT are simulated. LET stands for the linear energy transfer capacity of a particle, which refers to the amount of energy transferred by the particle to the irradiated substance on the unit path. The simulation results show that for GaN HEMTs, the single-event transient effect is more obvious when the device is in off-state than in on-state. The most sensitive location of GaN HEMTs to the single-event effect is in the region near the drain. The peak transient current increases with the increase in the drain bias and incident ion LET values. The drain charge collection time increases with the angle of incidence of heavy ion. Full article

Background: Low anterior resection syndrome (LARS) is a series of bowel dysfunction symptoms, including altered bowel frequency, irregular bowel rhythms, fecal incontinence, and constipation. LARS occurs in 80% of patients undergoing sphincter-preserving surgery, affecting patients’ quality of life along with social avoidance. Different measurements and treatments have been raised to deal with LARS, but no systematic standard has been developed. Objective and Methods: To promote the standardization of clinical trials and clinical management of LARS, this review summarizes the latest findings up until 2023 regarding the diagnostic criteria, assessment protocols, and treatment modalities for postoperative LARS in rectal cancer. Results: The diagnostic criteria for LARS need to be updated to the definition proposed by the LARS International Collaborative Group, replacing the current application of the LARS score. In both clinical trials and clinical treatment, the severity of LARS should be assessed using at least one symptom assessment questionnaire, the LARS score or MSKCC BFI, and at least one scale related to quality of life. Anorectal manometry, fecoflowmetry, endoscopic ultrasonography, and pelvic floor muscle strength testing are recommended to be adopted only in clinical trials. After analysis of the latest literature on LARS treatment, a stepwise classification model is established for the standardized clinical management of LARS. Patients with minor LARS can start with first-line treatment, including management of self-behavior with an emphasis on diet modification and medication. Lamosetron, colesevelam hydrochloride, and loperamide are common antidiarrheal agents. Second-line management indicates multi-mode pelvic floor rehabilitation and transanal irrigation. Patients with major LARS should select single or several treatments in second-line management. Refractory LARS can choose antegrade enema, neuromodulation, or colostomy. Conclusions: In clinical trials of LARS treatment between 2020 and 2022, the eligibility criteria and evaluation system have been variable. Therefore, it is urgent to create a standard for the diagnosis, assessment, and treatment of LARS. Failure to set placebos and differentiate subgroups are limitations of many current LARS studies. Randomized controlled trials comparing diverse therapies and long-term outcomes are absent, as well. Moreover, a new scale needs to be developed to incorporate the patient’s perspective and facilitate outpatient follow-up. Though the establishment of a stepwise classification model for LARS treatment here is indispensable, the refinement of the guidelines may be improved by more standardized studies. Full article

With the advantages of superior wear resistance, mechanical durability, and stability, the liquid–solid triboelectric nanogenerator (LS-TENG) has been attracting much attention in the field of energy harvesting and self-powered sensors. However, most of the studies on LS-TENG focused on device innovations, changes in solid materials, and the effect of solid properties on output performance, and there is a lack of studies on liquids, especially at the molecular level. A U-tube LS-TENG was assembled to conduct experiments, whereby the effects of molecular structures, including molecular composition, carbon chain length, functional groups and material properties on the output performance were investigated. The deuterium replacing hydrogen and the atomic compositions could not achieve the enhancement of the output performance. Whether the chemical functional groups improve the output performance of LS-TENG depends on the mating solid material. Hydroxyl and cyanogenic groups can improve the output performance for the FEP case, while amide and cyanogenic groups can improve the output performance for the PTFE case. The order of output performances for functional groups of four groups of liquids with both FEP and PTFE materials is also obtained. It was also found that the dielectric constant is not positively correlated with the output performance. The results of this study might provide a reference for the deeper study and application of LS-TENG. Full article