Improved nitrogen reduction activity of NbSe2 tuned by edge chirality

Efficient catalysts for the electroreduction of N₂ to NH₃ are of paramount importance for sustainable ammonia production. Recently, it was reported that NbSe₂ nanosheets exhibit an excellent catalytic activity for nitrogen reduction under ambient conditions. However, existing theoretical calculations suggested an overpotential over 3.0 V, which is too high to interpret the experimental observations. To reveal the underlying mechanism of the high catalytic activity, in this work, we assessed NbSe₂ edges with different chirality and Se vacancies by using first principles calculations. Our results show that N₂ can be efficiently reduced to NH₃ on a pristine zigzag edge via the enzymatic pathway with an overpotential of 0.45 V. Electronic structure analysis demonstrates that the N₂ molecule is activated by the back-donation mechanism. The efficient tuning of the local chemical environments by edge chirality provides a promising approach for catalyst design.

The zigzag edge of the NbSe₂ monolayer exhibits an overpotential as low as 0.45 V along the enzymatic pathway.     

不同公式计算角膜屈光术后白内障患者IOL屈光度的准确性比较

目的：对比观察5种人工晶状体(IOL)计算公式在角膜屈光术后白内障患者IOL屈光度计算中的准确性。

方法：前瞻性系列病例研究。收集2021-09/2023-03就诊于济南明水眼科医院的既往行角膜屈光手术矫正近视的白内障患者23例34眼,其中准分子角膜切削术(PRK)手术史1例1眼,准分子原位角膜磨镶术(LASIK)术后22例33眼。白内障术前采用IOL Master 700测量眼生物学参数; Pentacam眼前节分析系统测量角膜真实净屈光力(TNP); 眼前节OCT测量净角膜屈光力(NCP)、角膜后表面屈光力、角膜厚度(CCT)。采用Shammas公式、Haigis-L公式、Potvin-Hill Pentacam公式、OCT公式、Barrett True K公式进行IOL度数计算后综合选择合适的IOL度数。术后1 mo在客观验光的基础上行主觉验光获得术后实际屈光状态,根据术后验光结果计算5种公式的屈光预测误差(RPE),其绝对值为屈光绝对误差(RAE),比较RPE与0的差异及不同公式间RPE、RAE的差异,并统计RAE≤0.5 D、≤1.0 D的眼数所占百分比。

结果：5种公式计算所得的RPE与0比较均无差异(均P>0.05)。5种计算公式的RPE、RAE整体无差异(F=0.554,P=0.696; H=4.402,P=0.354); Potvin-Hill Pentacam公式、Barrett True K公式的RAE在≤0.5 D内的眼占比分别为26眼(76%)、24眼(71%),在≤1.0 D内的眼占比均为33眼(97%)。

结论：Barrett True K 公式、Potvin-Hill Pentacam公式在角膜屈光术后白内障患者IOL屈光度计算中表现出较高的预测性。由于此类人群角膜屈光力存在差异,IOL度数计算问题仍需要进一步研究,临床上建议多种公式综合考虑。     

细针穿刺肝脏孤立性坏死结节的临床病理特征

目的研究B超下穿刺肝孤立性坏死结节的临床及病理学特点。方法收集32例肝孤立性坏死结节的临床资料,并在光镜下观察其细针穿刺组织病理形态,同时复习相关文献。结果本组男性21例,女性11例,平均年龄46.8岁,结节直径0.8~4.0 cm,临床及影像学缺少特异表现,光镜下结节中央为凝固性坏死,坏死外周围绕着一层弹力纤维及胶原组织,伴少数炎细胞浸润,结节周围的肝细胞基本正常。结论肝孤立性坏死结节是一种少见的非肿瘤性结节状病变,对B超引导下穿刺标本进行组织病理学观察能够准确诊断。     

A Novel Herbal Extract Blend Product Prevents Particulate Matters-Induced Inflammation by Improving Gut Microbiota and Maintaining the Integrity of the Intestinal Barrier

Air pollutants of PM2.5 can alter the composition of gut microbiota and lead to inflammation in the lung and gastrointestinal tract. The aim of this study was to evaluate the protective effect of a novel herbal extract blend, FC, composed of Lonicera japonica extract, Momordica grosvenori extract, and broccoli seed extract, on PM2.5-induced inflammation in the respiratory and intestinal tract. A549 cells and THP-1 cells, as well as C57BL/6 mice, were stimulated with PM2.5 to establish in vitro and in vivo exposure models. The models were treated with or without FC. The expression of inflammatory cytokines and tight junction proteins were studied. Proteomic analysis was performed to elucidate mechanisms. Mouse feces were collected for gut microbiota analysis. FC was shown to modulate the upregulation of pro-inflammatory cytokines mRNA expression in A549 and THP-1 cells and downregulated tight junction proteins mRNA expression in A549 cells due to PM2.5 stimulation. In animal models, the decreased expression of the anti-inflammatory factor il-10, tight junction protein ZO-1, and the elevated expression of COX-2 induced by PM2.5 were improved by FC intervention, which may be associated with zo-1 and cox-2 signaling pathways. In addition, FC was shown to improve the gut microbiota by increasing the abundance of beneficial bacteria.     

Liquid Guayule Natural Rubber,a Sustainable Processing Aid,Enhances the Processability,Durability and Dynamic Mechanical Properties of Rubber Composites

Petroleum-based oils are widely used as processing aids in rubber composites to improve processability but can adversely affect rubber composite performance and increase carbon footprint. In this research, liquid guayule natural rubber (LGNR), produced from guayule natural rubber, was used as a renewable processing aid to replace naphthenic oil (NO) in Hevea natural rubber, styrene-butadiene rubber (SBR) and guayule natural rubber (GNR) composites. The rheological properties, thermal stability, glass transition temperature, dynamic mechanical properties, aging, and ozone resistance of rubber composites with and without NO or LGNR were compared. Natural and synthetic rubber composites made with LGNR had similar processability to those made with NO, but had improved thermal stability, mechanical properties after aging, and ozone resistance. This was due to the strong LGNR–filler interaction and additional crosslinks formed between LGNR and the rubber matrices. The glass transition temperature of SBR composites was reduced by LGNR because of its increased molecular mobility. Thus, unlike NO, LGNR processing aid can simultaneously improve rubber composite durability, dynamic performance and renewability. The commercialization of LGNR has the potential to open a new sustainable processing-aid market.     

不同模式新辅助治疗食管癌的疗效分析

目的 探讨食管癌不同模式新辅助治疗的疗效分析。方法 回顾性分析2015年1月至2022年5月于安阳市肿瘤医院行新辅助治疗的食管鳞癌(ESCC)患者的资料,共纳入542例患者,其中放化疗(NCRT)组137例,化疗(NCT)组241例,免疫加化疗(NICT)组164例;女性198例,男性344例;≤65岁289例,＞65岁253例。首要研究终点包括主要病理缓解(MPR)率、病理完全缓解(pCR) 率,次要研究终点包括总生存(OS)、无进展生存(PFS)和安全性。生存分析采用Kaplan-Meier方法,并采用Log-rank检验进行组间比较。采用Cox比例风险回归模型进行预后因素分析。结果 NCRT组的MPR率和pCR率分别为66.4%(91/137)和35.8%(49/137),NCT组分别为35.3%(85/241)和6.6%(16/241),NICT组分别为63.4%(104/164)和31.1%(51/164)(χ²=1.67, P＜0.001)。NCRT组的1、2、3年的OS分别为89.8%、82.3%、72.3%,NCT组分别为85.9%、71.4%、61.4%,NICT组分别为91.9%、81.5%、77.8%,差异有统计学意义(χ²=9.20,P＜0.01);NCRT组的1、2、3年的PFS分别为81.5%、67.9%、66.6%,NCT组分别75.9%、61.0%、53.5%,NICT组分别为80.1%、65.5%、65.3%,差异有统计学意义(χ²=4.62,P＜0.05)。多因素分析显示,治疗方式、T分期、N分期是OS的独立影响因素(P＜0.05)。3组不良反应及术后并发症差异无统计学意义(P＞0.05)。结论 与NCT对比,NICT与NCRT有更高的pCR、MPR和生存获益,因此新辅助免疫可作为食管癌术前治疗手段之一,但仍需大型的随机对照研究进一步证实。     

超声诊断颌下腺炎的临床应用

目的探讨超声诊断颌下腺炎的临床应用价值。方法选取101例经手术证实的颌下腺炎的超声图像,分析颌下腺的大小、形态、内部回声及彩色血流情况。结果101例颌下腺炎中,急性炎症2例,慢性炎症99例,超声与手术病理结果符合率为98%。结论超声对颌下腺炎的诊断准确率较高,并能与颌下区占位性病变相鉴别。     

利妥昔单抗治疗难治性激素耐药型肾病综合征的疗效和安全性

目的:探讨利妥昔单抗(RTX)治疗儿童难治性激素耐药型肾病综合征(SRNS)的疗效和安全性。方法:回顾性分析2013年9月至2018年3月东部战区总医院儿科收治并接受RTX治疗的10例难治性SRNS患儿的临床资料。结果:10例患儿发病年龄(4.47±2.75)岁,男女各5例;5例(50%)肾活检为局灶节段性肾小球肾炎,...     

Study on the Material Properties of Microconcrete by Dynamic Model Test

As an important water conveying structure, the seismic safety of the hydraulic aqueduct has attracted considerable interest. Different from the general bridge structure, the seismic analysis of the aqueduct structure needs to consider its fluid–structure interaction. The existing numerical simulation methods cannot truly reflect the fluid–solid coupling mechanism. Therefore, scholars began to use shaking table tests to study the fluid–structure interaction mechanism. However, the research is immature, and it is mostly focused on the seismic response analysis, and there are few studies on the model test similarity ratio and model material properties. Based on this, in this paper, according to the requirements of the test similarity ratio, the orthogonal experiment was used to explore the influence of barite sand content, water–cement ratio, fine sand ratio, and lime ratio on the mechanical properties of microconcrete. The performance indicators of microconcrete under different mix ratios vary widely, with a minimum variation of 19% and a maximum of 102%. Barite sand has the most significant control effect on the density, and the water–cement ratio has the most significant control effect on the compressive strength and elastic modulus. The density variation range is 2.37–2.81 g/cm³, the cube compressive strength variation range is 18.37–36.94 MPa, and the elastic modulus variation range is 2.11 × 10⁴–3.28 × 10⁴ MPa. This study will provide certain evidence for the similarity ratio design and material selection of the scaled model test of the fluid–solid coupling structure.