社区衰弱和肌少症老年人膳食营养干预的障碍和促进因素:质性 研究的meta整合

目的随着老龄化社会进程加速,老年人躯体衰弱和肌少症的患病率逐年上升,并带来诸多不良影响。膳食营养是防治躯体衰弱和肌少症的重要方式,但在社区环境中实施膳食营养干预受到诸多复杂因素影响。本综述旨在对相关研究中的促进和障碍因素进行系统综述,为制订相关健康管理方案提供参考。方法在Pub Med. .Web of Science 、Medline(Ovid). Embase(Ovid)和Cochrane Library 数据库进行检索,发表时间限定为建库至2023年1月。使用主题词和自由词组合完成检索。使用英国牛津大学循证医学中心质性研究质量评价工具(the Critical Appraisal Skills Program Qualiative Sudies Checklist)对 纳入研究进行质量评价。利用社会生态建模框架对提取的信息进行编码和分析。本综述方案已在PROSPERO注册(CRD42022381339)。结果共纳入10项研究。其中,4项研究仅进行营养相关干预,而膳食营养和运动干预相结合的有6项。根据社会生态模型,从个体特征、外部环境和干预措施3个层面对促进和障碍因素进行了总结,包含10个副主题。结论对社区中的躯体衰弱和肌少症老年人实施膳食营养干预措施时,应整合个人内部动机和外部支持,为参与者制订“量身定制”的干预方案,并最大程度地优化可利用的人力和物理资源。

Concentration of linoleic acid from cottonseed oil by starch complexation

The extraction of linoleic acid from fatty acids(FA) of the cottonseed oil using starch–FA complexes was developed for the first time. We showed that starch can form inclusion complexes of different strengths with FA and that the different strengths stem from the differences in chain length, degree of unsaturation, and position of double bonds of FA. The optimal separation conditions were determined as follows: The inclusion temperature is 69 °C, the inclusion time is 30 min, the starch/FA mass ratio is 10:1, and the ratio of the volume of methanol–water solution and the mass of FA is 18:1. Compared to urea inclusion complexation, starch complexation has milder reaction temperature and shorter reaction time. Under these conditions, linoleic acid can be concentrated from 38.9% to 70.04% by one-off extraction. Moreover, the experimental results demonstrate the almost perfect reusability of starch. These results show that starch complexation is a promising method that can be used to obtain highly concentrated linoleic acid from cottonseed oil.

Photoinhibition of Leaves with Different Photosynthetic Carbon Assimilation Characteristics in Maize (<i>Zea mays</i>)

Strong light decreases the rate of photosynthesis and assimilates production of crop plants. Plants with different carbon reduction cycles respond differently to strong light stress. However, variation in photoinhibition in leaves with different photosynthetic characteristics in maize is not clear. In this experiment, we used the first leaves (with an incomplete C4 cycle) and fifth leaves (with a complete C4 cycle) of maize plants as well as the fifth leaves (C3 cycle) of tobacco plants as a reference to measure the photosynthetic rate (PN) and chlorophyll a parameters under strong light stress. During treatment, PN, the maximal fluorescence (Fm), the maximal quantum yield of PSII photochemistry (Fv/Fm), and the number of active photosystem II (PSII) reaction centers per excited cross-section (RC/CSm) declined dramatically in all three types of leaves but to different degrees. PN, Fm, Fv/Fm, and RC/CSm were less inhibited by strong light in C4 leaves. The results showed that maize C4 leaves with higher rates of photosynthesis are more tolerant to strong light stress than incomplete C4 leaves, and the carbon reduction cycle is more important to photoprotection in C4 leaves, while state transition is critical in incomplete C4 leaves.

Highly efficient catalyzed by imidazolium-based dual-sulfonic acid functionalized ionic liquids for liquid phase Beckmann rearrangement:experiments and COSMO-RS calculations

A production technique with the high yield and environmentally friendly process need be developed forε-Caprolactam(CPL)in the chemical industry.This technology is highly desired to design and synthesize high--performance catalysts for liquid phase Beckmann rearrangement of cyclohexanone oxime(CHO)to CPL.In this work,3-methyl-1-(propyl-4-sulfonyl)imidazolium methanesulfonate([PHSO_(3)MIM][MSA])with highly efficient and excellent yield is synthesized successfully.When the optimum molar ratio of ZnCl_(2)over[PHSO_(3)MIM][MSA]was 0.02,it exhibits the high selectivity(94%)of CPL at 90℃for 1 h.Interestingly,Fourier-transform infrared(FT-IR)investigations show that the functional Br∅nsted-Lewis acidic types of ionic liquids(ILs)are formed by the uniformly distributed ZnCl_(2)and[PHSO_(3)MIM][MSA].In addition,the hydrogen bond(H-bond)is formed between CHO and ILs.After ten reaction cycles,no significant structure changes are observed in the recovered[PHSO_(3)MIM][MSA]-ZnCl_(2).The solubilities of ILs are predicted by using COSMO-RS model,the results show that[PHSO_(3)MIM][MSA]is a promising candidate for the liquid phase Beckmann rearrangement of CHO into CPL.Finally,a theoretical model of the H-bond interactions between ILs and CHO is further confirmed to support the advance of reaction mechanism.A feasible way is provided for the CPL production technique in the liquid phase Beckmann rearrangement reaction.

Exploring key developmental phases and phase-specific genes across the entirety of anther development in maize

Anther development from stamen primordium to pollen dispersal is complex and essential to sexual reproduction.How this highly dynamic and complex developmental process is controlled genetically is not well understood,especially for genes involved in specific key developmental phases.Here we generated RNA sequencing libraries spanning 10 key stages across the entirety of anther development in maize(Zea mays).Global transcriptome analyses revealed distinct phases of cell division and expansion,meiosis,pollen maturation,and mature pollen,for which we detected 50,245,42,and 414 phase-specific marker genes,respectively.Phase-specific transcription factor genes were significantly enriched in the phase of meiosis.The phase-specific expression of these marker genes was highly conserved among the maize lines Chang7-2 and W23,indicating they might have important roles in anther development.We explored a desiccationrelated protein gene,ZmDRP1,which was exclusively expressed in the tapetum from the tetrad to the uninucleate microspore stage,by generating knockout mutants.Notably,mutants in ZmDRP1 were completely male-sterile,with abnormal Ubisch bodies and defective pollen exine.Our work provides a glimpse into the gene expression dynamics and a valuable resource for exploring the roles of key phase-specific genes that regulate anther development.

Ferroelectricity in hBN intercalated double-layer graphene

Van der Waals(vdW)assembly of two-dimensional materials has long been recognized as a powerful tool for creating unique systems with properties that cannot be found in natural compounds[Nature 499,419(2013)].However,among the variety of vdW heterostructures and their various properties,only a few have revealed metallic and ferroelectric behaviour signatures[Sci.Adv.5,eaax5080(2019);Nature 560,336(2018)].Here we show ferroelectric semimetal made of double-gated double-layer graphene separated by an atomically thin crystal of hexagonal boron nitride.The structure demonstrates high room temperature mobility of the order of 10 m2·V^(−1)·s^(−1) and exhibits ambipolar switching in response to the external electric field.The observed hysteresis is reversible and persists above room temperature.Our fabrication method expands the family of ferroelectric vdW compounds and offers a promising route for developing novel phase-changing devices.A possible microscopic model of ferroelectricity is discussed.