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摘要：

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  2-Propenoic acid, 2-[1-(3,3-dimethylcyclohexyl)ethoxy]-2-methylpropyl ester; a safety assessment based on RIFM's criteria.
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  A safety assessment based on 7 human health endpoints plus environmental.
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  All endpoints were cleared using target data, read-across, and/or TTC.

关键词： 子痫前期   胎儿宫内生长受限   IGF-1   PAPP-A   VEGF  

摘要： 目的:探讨子痫前期孕妇血清胰岛素样生长因子-1(Insulin-like growth factor-1,IGF-1)、妊娠相关血浆蛋白A(Pregnancy-associated plasma protein A,PAPP-A)、血管内皮生长因子(Vascular endothelial growth factor,VEGF)水平及其联合检测对子痫前期孕妇发生胎儿宫内生长受限(Fetal growth restriction,FGR)的预测价值。方法:回顾性选取2023年1月至2024年1月郸城县妇幼保健院收治的86例子痫前期孕妇为子痫前期组,根据生产时是否发生FGR分为发生组、未发生组;另选取同期正常孕检的86例健康孕妇为健康对照组,比较各组血清IGF-1、PAPP-A、VEGF水平;分析上述血清指标与子痫前期孕妇发生FGR的相关性;分析上述血清指标对子痫前期孕妇发生FGR的早期预测效能。结果:子痫前期组血清IGF-1、PAPP-A、VEGF水平低于健康对照组(P<0.05);发生组上述血清指标低于未发生组(P<0.05);上述血清指标与子痫前期孕妇发生FGR呈负相关(P<0.05);上述血清指标联合检测预测子痫前期孕妇发生FGR的曲线下面积(Area under curve,AUC)高于上述指标单独预测值(P<0.05)。结论:血清IGF-1、PAPP-A、VEGF水平与子痫前期孕妇发生FGR关系密切,各指标联合检测对子痫前期孕妇发生FGR具有较高的早期预测效能。

关键词： 樱桃番茄   MA包装   1-MCP   贮藏保鲜   品质变化  

摘要： 樱桃番茄采后呼吸强度大、水分蒸发快,易出现软化、腐烂、营养流失等问题,货架期短,严重限制了其流通销售。本研究以千禧品种樱桃番茄为试验材料,设置对照组(CK,无包装)、PE包装组、PVC包装组、PE包装加1-MCP处理组、PVC包装加1-MCP处理组5个处理,在温度10±1℃、相对湿度85%~90%的条件下贮藏21d,每3天取样测定失重率、硬度、腐烂率、可溶性固形物含量、相对电导率、维生素C含量、丙二醛含量等指标,对比不同处理的保鲜效果。结果表明:MA包装结合1-MCP处理能显著延缓樱桃番茄的采后衰老进程,其中PE包装加1-MCP处理的保鲜效果最优,贮藏21d时失重率仅为1.52%,腐烂率7%,硬度保持在2.49kg·cm^(-2),可溶性固形物含量6.29%,维生素C保留率达到46.5%,显著优于其他处理组;其次为PVC包装加1-MCP处理,单独PE包装的效果优于单独PVC包装。本研究结果可为樱桃番茄采后保鲜技术的实际应用提供参考,有效降低采后损失。

关键词： NO2 gas sensor application   2D materials   X-ray photoelectron spectroscopy   HRTEM   Chemo-resistive sensors  

摘要：

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  Single-crystal Ta-doped WSe₂ (Ta_xW_1−xSe₂) enables highly sensitive NO₂ detection at room temperature.
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  Ta_xW_1−xSe₂ devices achieve a strong sensing response (∼200%) at 100 ppb NO₂.
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  Ultralow-concentration detection down to 25 ppb with ∼80% response is demonstrated.
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  Ta_0.002W_0.998Se₂ exhibits the highest sensitivity and optimal sensing performance.

关键词： 血管形成   甲基结合蛋白1   人脐静脉内皮细胞   血管内皮生长因子A   细胞增殖   细胞迁移  

摘要： 目的探讨甲基结合蛋白1(MBD1)对人脐静脉内皮细胞(HUVECs)增殖、迁移以及血管形成的影响。方法设置MBD1敲低(sh-MBD1)组和对照(sh-NC)组。使用靶向人MBD1基因shRNA LV3(H1/GFP&Puro)-MBD1-HOMO-270的慢病毒液和携带Scramble shRNA的慢病毒液LV3(H1/GFP&Puro)-NC感染HUVECs细胞,使用嘌呤霉素筛选感染成功的细胞。通过实时定量PCR(RT-qPCR)以及蛋白质印迹检测MBD1基因的沉默效率。通过CCK-8和克隆形成实验检测细胞增殖情况,流式细胞术检测细胞周期改变,细胞划痕实验以及Transwell实验检测细胞迁移速度,血管形成实验检测MBD1对HUVECs的血管形成能力的影响,免疫荧光检测MBD1对HUVECs中血管内皮生长因子A(VEGFA)表达的影响。结果成功构建MBD1敲低的HUVECs;与sh-NC组相比,sh-MBD1组细胞的增殖能力、增殖指数以及迁移能力显著降低(P<0.0001);sh-MBD1组细胞体外生成的血管总长度、血管闭合环路以及血管分支点均低于sh-NC组细胞(P<0.01);sh-MBD1组细胞中VEGFA表达量较对照细胞显著降低(P<0.0001)。结论MBD1促进人脐静脉内皮细胞增殖、迁移和血管形成,且促进作用可能通过调控VEGFA的表达实现。

关键词： 1,3-Propanediol   Activated carbon   Chitosan   Clostridium butyricum   Dynamic metabolic flux analysis   Lactic acid  

摘要： The anaerobic fermentation of crude glycerol to 1,3-propanediol by Clostridium butyricum is energetically favorable due to the low stirring rate and unsterilized fermentation environment. However, its efficiency is severely limited by the accumulation of acid by-products. Although metabolic engineering is commonly employed to overcome such challenges, the inherent oxygen sensitivity of C. butyricum significantly hinders genetic modification and metabolic analysis under the required conditions. Therefore, we adopted an alternative strategy of supplementing renewable materials to regulate by-products formation and improve the 1,3-propanediol concentration. Among them, chitosan could reduce the concentration of most by-products, increasing the concentration and yield of 1,3-propanediol to 53.55 g/L and 0.57 g/g. At the same time, activated carbon could achieve co-production of 1,3-propanediol (62.12 g/L) and lactic acid (38.74 g/L) through selective adsorption of by-products. Combined with the adsorption equation-assisted dynamic metabolic flux analysis developed in this work, we demonstrated the by-product regulation produces more NADH and brings dynamic balance to the reducing power. This work offers enlightenment and reference for a similar production process, which is of great potential to reduce the concentration of most by-products in future large-scale 1,3-propanediol production.

关键词： Analog front end   Chopper   Dual-Phase-Ping-Pong auto-zero   Programmable instrumentation amplifier   Sigma-Delta modulator  

摘要： An analog front-end (AFE) with a 500-Hz bandwidth and a signal-to-noise and distortion ratio (SNDR) of 98.1 dB is presented for biological signal acquisition. To reduce structural complexity, the proposed dual-amplifier programmable gain instrumentation amplifier (PGIA) integrates the functions of instrumentation amplifier (IA) and programmable gain amplifier (PGA). To minimize the offset voltage and 1/f noise of the PGIA, dual-phase ping-pong auto-zero (DPAZ) and chopper stabilization techniques are employed. Compared to traditional input-offset and output-offset storage techniques, the DPAZ method not only doubles the signal bandwidth but also eliminates signal-path capacitance and relaxes the stability requirements for operational amplifiers. Moreover, the chopper technique is applied to the first-stage integrator of a second-order cascade of integrators feedback (CIFB) Sigma-Delta modulator (SDM), effectively overcoming the limitations of AFE accuracy caused by offset voltage and 1/f noise. The proposed AFE is designed with 0.18-μm CMOS and occupies an active area of 0.237 mm². Simulation results show that under 1.8-V supply, the DPAZ technique reduces the average offset voltage of the PGIA from 28.2 μV to 3.02 μV, and the root mean square (RMS) equivalent input-referred noise (IRN) voltage within 500-Hz bandwidth decreases from 9.9 μV to 1.64 μV. At a sampling rate of 1.024 MHz, an oversampling ratio (OSR) of 1024, and an input signal level of −5 dBFS, the SNDR of the SDM with the chopper technique improves from 97.7 dB to 99.4 dB with negligible additional power consumption, achieving a FoM_SNDR of 166.5 dB.