Physiological Responses of Different Kinds of Vegetable Seedlings to Polycyclic Aromatic Hydrocarbons Stress

This study was conducted to explore the effects of polycyclic aromatic hydrocarbons (PAHs) on the growth and physiological characteristics of vegetable seedlings.Cucumber,Chinese cabbage and radish were cultured under the stress of 16 PAHs at different concentrations of 0.3,0.6 and 0.9 mg/L,respectively,with the seedlings cultured without PAHs as the control,to study the growth and physiological responses of various vegetable seedlings under PAHs stress.The results showed that the leaf width,fresh weight,CAT activity and POD activity of cucumber and the chlorophyll b content and CAT activity of radish reached the minimum values when treated with 0.3 mg/L PAHs.When the treatment concentration was 0.6 mg/L,the POD activity of cucumber,the vitamin C content of Chinese cabbage and the MDA content of radish were the smallest.The dry weight of cucumber,the fresh weight of Chinese cabbage and the fresh weight and POD activity of radish reached the minimums under the treatment of 0.9 mg/L PAHs.Different concentrations of PAHs could promote the synthesis and photosynthesis of chlorophyll in cucumber and Chinese cabbage leaves and the vitamin C content in radish.With the increase of PAHs treatment concentration,the MDA contents of cucumber and Chinese cabbage were on the increase,and reached the maximums under the treatment of 0.9 mg/L PAHs.One of the reasons why different kinds of vegetable seedlings have different physiological responses to PAHs may be related to the differences in the amount of PAHs absorbed by different leaf structures.

Generalized Pose Decoupled Network for Unsupervised 3D Skeleton Sequence-Based Action Representation Learning

Human action representation is derived from the description of human shape and motion.The traditional unsupervised 3-dimensional(3D)human action representation learning method uses a recurrent neural network(RNN)-based autoencoder to reconstruct the input pose sequence and then takes the midlevel feature of the autoencoder as representation.Although RNN can implicitly learn a certain amount of motion information,the extracted representation mainly describes the human shape and is insufficient to describe motion information.Therefore,we first present a handcrafted motion feature called pose flow to guide the reconstruction of the autoencoder,whose midlevel feature is expected to describe motion information.The performance is limited as we observe that actions can be distinctive in either motion direction or motion norm.For example,we can distinguish“sitting down”and“standing up”from motion direction yet distinguish“running”and“jogging”from motion norm.In these cases,it is difficult to learn distinctive features from pose flow where direction and norm are mixed.To this end,we present an explicit pose decoupled flow network(PDF-E)to learn from direction and norm in a multi-task learning framework,where 1 encoder is used to generate representation and 2 decoders are used to generating direction and norm,respectively.Further,we use reconstructing the input pose sequence as an additional constraint and present a generalized PDF network(PDF-G)to learn both motion and shape information,which achieves state-of-the-art performances on large-scale and challenging 3D action recognition datasets including the NTU RGB+D 60 dataset and NTU RGB+D 120 dataset.

Ag@polydopamine-functionalized borate ester-linked chitosan hydrogel integrates monitoring with wound healing for epidermal sensor

Flexible sensors are promising candidates in personalized healthcare,while desired sensors that allow implantation for biomedical applications with optimal sensing and favorable biological properties remain challenges.Here,a multifunctional hydrogel sensor was developed with gallic acid-modified chitosan(CSGA)and 3-carboxyphenylboronic acid-modified chitosan(CSPBA)by encapsulating Agdecorated polydopamine(Ag@PDA)nanoparticles,namely Ag@PDA-(CSPBA/CSGA).The optimized hydrogel sensor showed desired sensitivity(gauge factor=2.49),a rapid response/recovery time of 263 ms and good durability.Due to the presence of abundant reactive groups within Ag@PDA-(CSPBA/CSGA),the hydrogel sensor exhibited a comprehensive performance of self-healing,tissue adhesiveness,antioxidative activity,and antibacterial effects against Escherichia coli(92.76%)and Staphylococcus aureus(98.08%).Moreover,the hydrogel sensor could be utilized as a wound dressing,facilitating accelerated wound closure and tissue regeneration.Both subtle activities and large-scale movements could be monitored and distinguished by the hydrogel sensor.This study provides a promising epidermal sensor that offers multifunctionality for health monitoring and wound management.