Experimental Study on Key Techniques for Indoor Cultivation of Sprout Vegetables in Families

This paper introduced the advantages of planting sprout vegetables in family rooms,expounded assembly principle of indoor cultivating device and the key techniques for indoor cultivating sprout vegetables in families.In the experiment,we assembled a set of indoor cultivating device for sprout vegetables,and summarized the indoor cultivating techniques of sprout vegetables in families.The indoor planting device was suitable for family members to cultivate sprout vegetables in the living rooms,kitchen,balcony and other corner space by using their spare time.It could not only provide high-quality vegetables for families,but also beautify the indoor environments of family rooms,and increase the oxygen content in rooms.This set of indoor cultivating device and techniques was suitable for planting various sprout vegetables(e.g.radish seedling,water spinach seedling,pea seedling,pine willow seedling,sunflower seedling and various bean seedlings,etc.).This is a set of high-efficient spatial planting technique in families,and also an effective way to increase organic vegetable supply for family.

Tyrosine promotes anthocyanin biosynthesis in pansy(Viola×wittrockiana)by inducing ABA synthesis

Viola×wittrockiana(pansy)is an important ornamental plant,particularly during winter and spring.In previous studies,we found that the tyrosine decarboxylase gene of pansy(VwTYDC)was expressed differently in blotched and non-blotched areas of pansy petals,suggesting that tyrosine may have a role in anthocyanin biosynthesis.In this study,we found that virus-induced gene silencing of VwTYDC caused an accumulation of pink pigmentation in pansy petals.Likewise,exogenous tyrosine treatment(TYRT)induced the formation of black stripes in nonblotched petal areas.Metabolome analysis indicated that the contents of two anthocyanins,cyanidin-3-O-glucoside and cyanidin-3-O-rutinoside,increased significantly in the TYRT areas.RT-qPCR results revealed that the anthocyanin-related genes VwHCT,VwC3′H,VwCHS,and VwUGT were upregulated in the same areas.Transcriptome analysis revealed that four genes involved in the abscisic acid(ABA)biosynthesis pathway(VwNCED,VwABA2,VwAAO3,and VwCYP707A)were significantly upregulated in the same TYRT areas.ABA content was measured by ESI-HPLCMS/MS,and ABA content was significantly higher in TYRT areas than in control areas.In addition,when exogenous ABA was spread onto nonblotched petal areas,anthocyanin biosynthesis genes were upregulated just as with tyrosine.Thus,transcriptome and metabolite analyses revealed a possible novel regulatory network for anthocyanin biosynthesis in which tyrosine induces ABA synthesis and ABA then promotes anthocyanin biosynthesis in pansy petals.

Street Stall Economy in China in the COVID-19 Era:Dilemmas and the International Experience of Promoting the Normalization of Street Stall Economy

Compared with those major policies that need to be practiced over the years,the street stall economy is more like a special means after the epidemic,resulting in a“short and brilliant”heat.Nevertheless,the street stall economy revives is facing several dilemmas.This paper reveals the dilemma of the prosperity and development of the stall economy before and after the epidemic,followed by the international experience and enlightenment of promoting the normalization of street stall economy,ranging from street vendor’s legal status and road administrative promotion to street food safety and environmental protection.To sum up,employment is the foundation of people’s livelihood and the source of wealth,hence,stall economy plays an indispensable role to create a win-win working world and promote the formation of a sustainable economic.

Reinforcement Learning-Based Dynamic Order Recommendation for On-Demand Food Delivery

On-demand food delivery(OFD)is gaining more and more popularity in modern society.As a kernel order assignment manner in OFD scenario,order recommendation directly influences the delivery efficiency of the platform and the delivery experience of riders.This paper addresses the dynamism of the order recommendation problem and proposes a reinforcement learning solution method.An actor-critic network based on long short term memory(LSTM)unit is designed to deal with the order-grabbing conflict between different riders.Besides,three rider sequencing rules are accordingly proposed to match different time steps of the LSTM unit with different riders.To test the performance of the proposed method,extensive experiments are conducted based on real data from Meituan delivery platform.The results demonstrate that the proposed reinforcement learning based order recommendation method can significantly increase the number of grabbed orders and reduce the number of order-grabbing conflicts,resulting in better delivery efficiency and experience for the platform and riders.

Efficient conversion of aromatic and phenylpropanoid alcohols to acids by the cascade biocatalysis of alcohol and aldehyde dehydrogenases

Benzyl and phenylpropanoid acids are widely used in organic synthesis of fine chemicals,such as pharmaceuticals and condiments.However,biocatalysis of these acids has received less attention than chemical synthesis.One of the main challenges for biological production is the limited availability of alcohol dehydrogenases and aldehyde dehydrogenases.Environmental microorganisms are potential sources of these enzymes.In this study,129 alcohol dehydrogenases and 42 aldehyde dehydrogenases from Corynebacterium glutamicum,Pseudomonas aeruginosa,and Bacillus subtilis were identified and explored with various benzyl and phenylpropanoid alcohol and aldehyde substrates,among which four alcohol dehydrogenases and four aldehyde dehydrogenases with broad substrate specificity and high catalytic activity were obtained.Moreover,a cascade whole-cell catalytic system including ADH-90,ALDH-40,and the NAD(P)H oxidase LreNox was established,which showed high efficiency in converting cinnamyl alcohol and p-methylbenzyl alcohol into the respective carboxylic acids.Remarkably,this biocatalytic system can be easily scaled up to gram-level production,facilitating preparation purposes.