食物源抗便秘因子保健机理的研究进展

功能性便秘有不同亚型,患者病情复杂且难以根治,因此对症摄入食物源抗便秘因子是功能性便秘患者最佳的日常养护手段。但目前食物源抗便秘因子的研究仍在起步阶段,系统地进行分型分类、深入了解各类型因子的保健机理、全面掌握抗便秘功效评价方法将有助于食物源抗便秘因子的深入研究及抗便秘功能食品的开发。本文提出了食物源抗便秘因子的分型分类方法,推测各类型抗便秘因子存在的对症便秘类型。基于上述两点判断,本文对不同类型食物源抗便秘因子保健机理进行总结论述,对目前采用的抗便秘功效评价方法进行汇总,针对目前食物源抗便秘因子研究存在的问题及未来食物源抗便秘因子的发展方向进行了展望,以期为该领域后续的深入研究提供参考。     

吡虫啉对意大利蜜蜂学习行为的影响

[目的]吡虫啉是一种新烟碱类杀虫剂,它作用于昆虫的烟碱型乙酰胆碱受体。通过喙伸反应研究了亚致死剂量吡虫啉对意大利蜜蜂工蜂学习行为的影响。[方法]喙伸反应(PER)是研究学习行为的经典方法。吡虫啉以0.1、0.15、0.65 ng/蜂3种剂量滴蜜蜂背板,最高浓度为室内毒力测定LD5值的1/10。[结果]0.65 ng/蜂剂量吡虫啉滴背板后,蜜蜂对稀糖水的敏感性显著降低。0.15、0.65 ng/蜂剂量吡虫啉对蜜蜂学习行为有影响。研究结果表明亚致死剂量吡虫啉对蜜蜂的学习行为有影响。[结论]喙伸反应试验可应用于亚致死剂量农药对蜜蜂学习行为的研究中。     

A fluorescent probe for the determination of Ce4+ in aqueous media

A rhodamine-based probe bearing an N,N-dimethylaniline unit was developed as a fluorescent chemodosimeter for Ce⁴⁺ in aqueous media. Importantly, the sensor can selectively respond to Ce⁴⁺ over other commonly coexistent metal ions (such as La³⁺, Ce³⁺, Pr³⁺, Nd³⁺, Sm³⁺, Eu³⁺, Gd³⁺, Er³⁺, Tb³⁺, Ho³⁺, Tm³⁺, Yb³⁺, Lu³⁺, Y³⁺) in aqueous media with a rapid response time. The system, which utilizes an irreversible Ce⁴⁺-promoted oxidation reaction, responds instantaneously at room temperature with linear proportionality to the amount of Ce⁴⁺.     

A counter electrode of multi-wall carbon nanotubes decorated with tungsten sulfide used in dye-sensitized solar cells

Multi-wall carbon nanotubes decorated with tungsten sulfide (MWCNTs-WS₂) were synthesized by using a hydrothermal method, and used as a low-cost platinum-free counter electrode for dye-sensitized solar cell (DSSC). Cyclic voltammetry and electrochemical impedance spectroscopy characterizations indicate that the counter electrode has a high catalytic activity for the reduction of triiodide to iodide and a low charge transfer resistance at the electrolyte–electrode interface. A DSSC based on this counter electrode achieves a high power conversion efficiency of 6.41% under a simulated solar illumination of 100 mW cm⁻² (AM 1.5). This efficiency is comparable to 6.56% for a DSSC with Pt counter electrode.     

An investigation on magnetic susceptibility of hazardous saline-alkaline soils from the contaminated Hai River Basin, China

Magnetic susceptibility can provide rich environmental information, especially for hazardous heavy metals and saline-alkaline in the contaminated soils. Magnetic susceptibility in four vertical profiles from saline-alkaline soils in lower Hai River basin was investigated. Soil sites were extended from alluvial fan to coastal plain areas. They are aligned along a latitudinal strip. Magnetic parameters including low/high frequency susceptibility, frequency-dependent susceptibility was measured. Moreover, some standard pedological parameters such as pH value and organic matter content were also determined. The results showed that low frequency magnetic susceptibility values is very high at the surface and decreases with the profile to a low value. In all profiles from alluvial fan frequency-dependent susceptibility greater than 3% may suggest the presence of relatively more super-paramagnetic particles. Magnetic susceptibility showed obvious vertical distribution in alluvial fan higher than coastal plain. No significant correlations between organic matter, pH and low frequency magnetic susceptibility were found, while there is a negative correlation between organic matter and frequency-dependent susceptibility. A positive correlation between pH and frequency-dependent susceptibility was found in the study areas.     

补料分批培养生产2-酮基-D-葡萄糖酸的研究

研究了补糖对荧光假单胞菌(Pseudomonas fluorescens)AR4生产2-酮基-D-葡萄糖酸的影响,并在50kL发酵罐上进行了补料分批培养工业应用性试验。研究结果表明,采用补料分批培养方法,能有效提高发酵液中的产物浓度;开始补糖时发酵液中的残糖浓度以3%～6%为宜;补料分批培养方法及AR4菌株可用于2-酮基-D-葡萄糖酸的工业化规模生产中。     

A conceptual CSO emission model: SEWSIM

CSO emission is widely considered a significant pollution source to receiving waters in urban areas. The existing deterministic sewer models are not able to predict CSO emission effectively. In this study, a conceptual CSO emission model SEWSIM has been developed using a powerful programming package MATLAB and SIMULINK. A sewer system consisting of an impervious catchment and a sewer network is schematised as two linear dynamic reservoirs. The following physical processes are conceptually modelled: rainfall-runoff; surface solids buildup and washoff; sewer sediment erosion and deposition. The model is suitable for both event-based and continuous simulations. Some simulation results demonstrate that SEWSIM predicts pollution load of CSO emission more effectively than deterministic models.     

Application of near-infrared absorbing heptamethine cyanine dyes as sensitizers for zinc oxide solar cell

Novel near-infrared absorbing heptamethine cyanine dyes derived from indole, benzoxazole, benzothiazole, and quinoline were synthesized and examined as sensitizers for a zinc oxide solar cell. A 2-carboxyphenylthio-substituted indolium heptamethine cyanine dye showed incident photon-to-current efficiency (IPCE) of 4.17% at 804 nm.     

Synthesis of highly active cobalt molybdenum sulfide nanosheets by a one-step hydrothermal method for use in dye-sensitized solar cells

Cobalt molybdenum sulfide (Co_(1 ? x)Mo_xS₂, x = 2/3, 1/2, 1/3) nanocomposites with hierarchical nanosheet structure are prepared on the flexible titanium foils by a facile hydrothermal method and used as the counter electrode (CE) materials for the dye-sensitized solar cells (DSSCs). It is interesting that the first produced MoS₂ nanosheets play an important role as the template for the continuously growing of the Co_(1 ? x)Mo _x S₂ nanosheets. Otherwise, it will grow up into octahedral CoS₂ in the synthesis system without the Mo source. The Co_(1 ? x)Mo _x S₂ CE demonstrates higher catalytic activity for the reduction of triiodide to iodide than that of the MoS_2, and CoS₂ CEs due to the Co_(1 ? x)Mo _x S₂ CE with thinner hierarchical nanosheets offers more catalytic active sites and exhibits additional synergistic effect of the combination of Mo and Co. The DSSC with Co_1/2Mo_1/2S₂ CE achieves a photovoltaic conversion efficiency of 9.16%, which is higher than that of the MoS₂ (8.27%) and CoS₂ (7.18%) CEs and even higher than that of the platinum CE (8.49%) under full sunlight illumination (100 mW cm^?2, AM1.5 G).     

Full-convolution Siamese network algorithm under deep learning used in tracking of facial video image in newborns

The Journal of Supercomputing - This study was carried out with the aim of exploring the full-convolution Siamese network (SiamFC) in the application of neonatal facial video image tracking,...