Improved interface passivation by optimizing a polysilicon film under different hydrogen dilution in N-type TOPCon silicon solar cells

The passivation properties of a polysilicon (poly-Si) thin film are the key for improving the photovoltaic performance of TOPCon silicon solar cells. In this work, we investigate the influence of the poly-Si microstructure on the interface passivation and photovoltaic performance in TOPCon solar cells. The poly-Si thin films are prepared from phosphorus-doped hydrogenated microcrystalline silicon (μc-Si:H) layers deposited via plasma enhanced chemical vapor deposition (PECVD) under different hydrogen dilutions and recrystallized by high temperature post-deposition annealing. The results revealed that, as the hydrogen dilution ratio increases, the microstructure of the pre-deposited films transforms from an amorphous phase to a microcrystalline phase. Meanwhile, the effective minority carrier lifetime of the symmetrically passivated contact structure shows a maximum value of 1.75 ms, implying that the efficient passivation at the c-Si interface is obtained which is mainly attributed to the joint enhancement of the improved field effect passivation from poly-Si films and the reduced defects density on the silicon surface. Consequently, the devices displayed excellent rectification behavior with a rectifying ratio of 3 × 10⁵, ascribed to the enhanced carrier transport with the high quality poly-Si film pre-deposited in the initial region of structural transition. Correspondingly, the obvious improvement of TOPCon solar cell performance was achieved, exhibiting an optimized conversion efficiency of 17.91%. The results provide an optimal design scheme for enhancing the photovoltaic properties of the TOPCon silicon solar cells.

The efficient passivation at the c-Si interface, and thus the enhanced photovoltaic performance in TOPCon silicon solar cells are obtained by appropriate hydrogen dilution of poly-Si film.     

大学生理想自我与现实自我差异问卷的编制

目的 编制大学生理想自我与现实自我差异问卷.方法 参考国内外文献,结合开放式调查和心理咨询实践,从心理健康角度编制大学生理想自我与现实自我差异问卷.结果 经因素分析,问卷由人际、品性、学业、情绪、家庭、魅力6个因素构成,累积解释率为54.18%,内部一致性信度和重测信度均在0.80以上.验证性因素分析表明,该问卷的理论结构模型拟合良好,CFI、NNFI均达到0.90以上,RMSEA小于0.08.结论 自编问卷具有良好的信度、效度,可用于大学生理想自我与现实自我差异的测量.     

Mixed Adenoneuroendocrine Carcinoma of the Gallbladder

Mixed adenoneuroendocrine carcinoma rarely occurs in the gallbladder. Most cases of cholecystic mixed adenoneuroendocrine carcinoma have been reported from Asia, North American, and Europe; however, there is scarce literature available on this tumor in other populations. Here, we report a case of mixed adenoneuroendocrine carcinoma in a Melanoderm woman who was initially suspected to have gallbladder cancer. No specific symptoms or abnormal blood test results were observed preoperatively. Magnetic resonance imaging revealed a 7-cm hypointense mass in the gallbladder fossa, which invaded the surrounding liver segments. Radical cholecystectomy, partial liver resection, and regional lymphadenectomy were performed. Finally, she was diagnosed as mixed adenoneuroendocrine carcinoma of the gallbladder upon postoperative pathological examination and immunohistochemical staining. She received six cycles of systemic chemotherapy and somatostatin treatment and survived 21 months after surgery. Our case highlights the fact that mixed adenoneuroendocrine carcinoma of the gallbladder can occur in African populations as well. Surgical approach combined with adjuvant chemotherapy and somatostatin treatment may contribute a relatively good survival outcome.     

布鲁氏菌病血清学诊断研究进展

本文综述了16种布鲁氏菌病血清学诊断方法,并对其优、缺点进行了分析.     

脑心通胶囊对冠心病无症状心肌缺血病人血管内皮依赖性舒张功能的影响

目的探讨脑心通胶囊治疗冠心病无症状心肌缺血(SMI)的疗效及其对血管内皮依赖性舒张功能的影响。方法随机将68例冠心病SMI病人分为两组,治疗组35例在常规药物治疗基础上加用脑心通胶囊治疗,对照组33例仅用常规药物治疗。治疗前后进行动态心电图及彩色多普勒超声检测,对缺血及血管内皮依赖性舒张功能的相关指标作对比观察。结果两组治疗12周后S,T段压低伴有症状的次数及其持续时间与无症状的ST段压低及其持续时间均有明显减少及缩短,与治疗前比较有统计学意义(P<0.05或P<0.01),治疗后两组比较也有统计学意义(P<0.05)。治疗组治疗后血管内皮依赖性舒张功能指标明显改善(P<0.01),与对照组比较差异亦有统计学意义(P<0.01)。用药期间病人无严重不良反应。结论脑心通胶囊对冠心病无症状心肌缺血有显著疗效,且能改善血管内皮依赖性舒张功能。     

Hepatitis B virus directly promotes collagen I expression of LX-2 cells without infection in vitro

Aim: To investigate direct effects of hepatitis B virus (HBV) on collagen type I in vitro. Methods: Collagen type I were measured after LX‐2 cell cultured with purified or serum HBV for 12, 24 and 48 h. Furthermore, evidence of HBV infection to LX‐2 were detected, and different inhibitors were used to identify pathways regulating collagen I expression. Results: The 3 × 10⁵ IU/mL purified/serum HBV increased collagen type I mRNA expression by 2.2‐/3.2‐ and 1.3‐/1.5‐fold at 24 and 48 h, respectively. Collagen type I protein in the supernatant of purified/serum HBV group also increased compared to the control group (408.0 ± 8.0/384.4 ± 6.8 vs 262.7 ± 15.7 ng/mL, P < 0.05). However, the 3 × 10⁷ IU/mL purified/serum HBV increased collagen type I expression similar to that of 3 × 10⁵ IU/mL, while 3 × 10³ IU/mL group showed no effect. Human HBV immunoglobulin alleviated HBV‐induced collagen I expression, but no evidence of HBV infection was found. Neutralization of transforming growth factor beta, tumor necrosis factor alpha, platelet‐derived growth factor, extracellular signal‐regulated kinase and TGF‐β receptor had no obvious inhibitory effects; only inhibition of p38 mitogen‐activated protein kinase decreased collagen type I mRNA expression by 0.5‐/0.4‐ and 0.4‐/0.3‐fold at 24 and 48 h, respectively. It reduced collagen type I protein in the purified/serum HBV group for 48 h (252.1 ± 14.1/251.7 ± 18.8 vs 403.9 ± 4.9/385.0 ± 4.2 ng/mL, P < 0.05). Conclusion: HBV directly promotes collagen type I expression of LX‐2 cells without infection in vitro.     

The sensing mechanism of a flavone-based ESIPT fluorescent chemodosimeter for selective recognition towards fluoride: a theoretical

The sensing mechanism of 3-hydroxyflavone-based (3-HF) fluorescent chemodosimeter 3-triisopropylsilylflavone (3-TPSF) for detecting fluoride (F⁻) has been theoretically investigated. The calculated Laplacian bond order confirms that the Si–O bond of 3-TPSF is the reaction site of F⁻. The free energy barrier of 18.33 kcal mol⁻¹ indicates that F-triggered desilylation reaction can occur and then form the anionic state of 3-HF (3-HF⁻) with a fluorescence peak at 545 nm. 3-HF⁻ captures H⁺ of the mixed aqueous medium to be transformed into 3-HF with an intramolecular hydrogen bond (O₁–H⋯O₂). The energy barrier of 1.86 kcal mol⁻¹ in the S₁ state obtained from the constructed potential energy curves confirms that the excited state intramolecular proton transfer (ESIPT) in 3-HF occurs to form a tautomer structure, which produces a long-wavelength emission of 549 nm. The fluorescence emitted from both 3-HF⁻ and 3-HF agrees with the experimental value of 530 nm appearing after adding F⁻. Charge transfer analyses indicate that the extent of intramolecular charge transfer in 3-HF⁻ is more intense than that of 3-TPSF, which induces a large Stokes shift of 180 nm. Therefore, the sensing mechanism is attributed to the combination of a large charge transfer feature and ESIPT that are caused by desilylation reaction. The significant fluorescence change makes 3-TPSF a chemodosimeter for detecting F⁻.

The sensing mechanism of 3-hydroxyflavone-based (3-HF) fluorescent chemodosimeter 3-triisopropylsilylflavone (3-TPSF) for detecting fluoride (F⁻) has been theoretically investigated.     

Mechanical properties of an interpenetrating network poly(vinyl alcohol)/alginate hydrogel with hierarchical fibrous structures

Bioinspired hierarchical fibrous structures were constructed in an interpenetrating poly(vinyl alcohol, PVA)/alginate hydrogel network to improve its mechanical properties. The interpenetrating hydrogel network with hierarchical fibrous structures was prepared by combining the confined drying method and freeze–thaw method. First, Ca²⁺ cross-linked alginate formed a nano–micro hierarchical fibrous structure via the confined drying method. Then, PVA that was uniformly distributed among the Ca²⁺–alginate chains was cross-linked by hydrogen bonding via the freeze–thaw method, further dividing the hierarchical fibers into finer fibers. The results of a tensile test demonstrated that both the tensile stress and fracture energy improved by more than double after the introduction of 2 wt% PVA, achieving a combination of high strength (∼12.9 MPa), high toughness (∼13.2 MJ m⁻³) and large strain (∼161.4%). Cyclic tensile tests showed that a hysteresis loop existed on the loading–unloading curves of the hydrogel along the fibrous directions, and a good self-recovery property emerged after resting for a period of time. The hydrogel with hierarchical fibrous structures constructed by alginate and PVA can be employed in biomedical applications in the future.

The mechanical properties both along and perpendicular to the fibrous directions were improved more than double after the construction of hierarchically arranged fibrous structures in the interpenetrating network PVA/alginate hydrogel.     

Non‐synonymous alterations in AKR7A3 and ABCA6 correlate with bleeding in aged patients treated with rivaroxaban

Rivaroxaban is an oral anticoagulant that inhibits thrombin and blocks coagulation cascade through directly inactivating factors Xa. Despite rivaroxaban is widely used for prevention and treatment of venous thrombosis, and its common adverse reactions have been reported, including abnormal coagulation, mucosal hemorrhage, hematuria, and intracranial hemorrhage. To explore potential drivers of individual differences in adverse reactions induced by rivaroxaban, we performed whole‐exome sequencing and found that AKR7A3 rs1738023/rs1738025 and ABCA6 rs7212506 are susceptible sites for rivaroxaban‐related bleeding in aged patients treated with rivaroxaban. Gene functional annotation and signaling pathway enrichment indicated that homozygous mutations in AKR7A3 and ABCA6 might alter normal rivaroxaban transport and metabolism, and lead to continuous accumulation of activated drugs and toxic substances in vivo. Our results suggested that interindividual differences in bleeding events induced by rivaroxaban may be potentially driven by genetic alterations related to abnormal metabolism and transport of rivaroxaban.

Study Highlights

• WHAT IS THE CURRENT KNOWLEDGE ON THE TOPIC?

Although rivaroxaban has been wildly used for the prevention and treatment of prevent of deep vein thrombosis without requiring routine coagulation monitoring, the adverse events, such as bleeding following rivaroxaban treatment, has not been fully addressed.

• WHAT QUESTION DID THIS STUDY ADDRESS?

The correlation between genetic variations and rivaroxaban treatment‐induced side effects (e.g., bleeding).

• WHAT DOES THIS STUDY ADD TO OUR KNOWLEDGE?

The AKR7A3 rs1738023/rs1738025 and ABCA6 rs7212506 confer susceptibility to adverse reactions caused by rivaroxaban.

• HOW MIGHT THIS CHANGE CLINICAL PHARMACOLOGY AND TRANSLATIONAL SCIENCE?

This study identified AKR7A3 and ABCA6 genes involved in drug metabolism and transport associated with susceptibility to rivaroxaban‐related bleeding events, and provided supporting evidence for the prevention and treatment of anticoagulant‐caused adverse effects.