Can targeted defense elicitation improve seaweed aquaculture?

Diseases increasingly threaten aquaculture of kelps and other seaweeds. At the same time, protection concepts that are based upon application of biocides are usually not applicable, as such compounds would be rapidly diluted in the sea, causing ecological damage. An alternative concept could be the application of immune stimulants to prevent and control diseases in farmed seaweeds. We here present a pilot study that investigated the effects of oligoalginate elicitation on juvenile and adult sporophytes of Saccharina japonica cultivated in China and on adult sporophytes of Saccharina latissima cultivated in Germany. In two consecutive years, treatment with oligoalginate clearly reduced the detachment of S. japonica juveniles from their substrate curtains during the nursery stage in greenhouse ponds. Oligoalginate elicitation also decreased the density of endobionts and the number of bacterial cells on sporophytes of S. latissima that were cultivated on sea-based rafts. However, the treatment increased the susceptibility of kelp adults to settlement of epibionts (barnacles in Germany and filamentous algal epiphytes in China). In addition, oligoalginate elicitation accelerated the aging of S. japonica adults. Based upon these findings, oligoalginate elicitation could be a feasible way to provide “environmentally friendly” protection of kelp juveniles in nurseries. The same treatment causes not only beneficial, but also unwanted effects in adult kelp sporophytes. Therefore, it is not recommended as a treatment after the juvenile stage is completed. Future tests with other elicitors and other cultivated seaweed species may allow for the development of more feasible applications of targeted defense elicitation in seaweed aquaculture

Design of ideological and political teaching case of analytical chemistry based on EDTA Titrator

Under the background of ideological and political education in the curriculum, according to the requirements of talent training in applied universities, the authors take the analytical chemistry curriculum as the implementation carrier of ideological and political education. Taking case teaching as an innovative means, a teaching case with EDTA as coordination titrant was designed. Based on the explanation of the principle that metal ions and coordination atoms coordinate to form stable compounds in Lewis acid-base theory, the ideological and political education was effectively combined with the teaching point of analytical chemistry knowledge, and the reason why EDTA had wide adaptability was proposed. From the perspective of ideological and political education, the teaching designs carried out with values education as the main line. The curriculum not only imparted professional knowledge, but also guided students' values. A reasonable teaching design can realize the educational goal of the same frequency resonance between professional courses and ideological and political education

Design of ideological and political teaching case of analytical chemistry based on EDTA Titrator

Under the background of ideological and political education in the curriculum, according to the requirements of talent training in applied universities, the authors take the analytical chemistry curriculum as the implementation carrier of ideological and political education. Taking case teaching as an innovative means, a teaching case with EDTA as coordination titrant was designed. Based on the explanation of the principle that metal ions and coordination atoms coordinate to form stable compounds in Lewis acid-base theory, the ideological and political education was effectively combined with the teaching point of analytical chemistry knowledge, and the reason why EDTA had wide adaptability was proposed. From the perspective of ideological and political education, the teaching designs carried out with values education as the main line. The curriculum not only imparted professional knowledge, but also guided students' values. A reasonable teaching design can realize the educational goal of the same frequency resonance between professional courses and ideological and political education

Estimation of Time-Frequency Muscle Synergy in Wrist Movements

Muscle synergy analysis is a kind of modularized decomposition of muscles during exercise controlled by the central nervous system (CNS). It can not only extract the synergistic muscles in exercise, but also obtain the activation states of muscles to reflect the coordination and control relationship between muscles. However, previous studies have mainly focused on the time-domain synergy without considering the frequency-specific characteristics within synergy structures. Therefore, this study proposes a novel method, named time-frequency non-negative matrix factorization (TF-NMF), to explore the time-varying regularity of muscle synergy characteristics of multi-channel surface electromyogram (sEMG) signals at different frequency bands. In this method, the wavelet packet transform (WPT) is used to transform the time-scale signals into time-frequency dimension. Then, the NMF method is calculated in each time-frequency window to extract the synergy modules. Finally, this method is used to analyze the sEMG signals recorded from 8 muscles during the conversion between wrist flexion (WF stage) and wrist extension (WE stage) movements in 12 healthy people. The experimental results show that the number of synergy modules in wrist flexion transmission to wrist extension (Motion Conversion, MC stage) is more than that in the WF stage and WE stage. Furthermore, the number of flexor and extensor muscle synergies in the frequency band of 0–125 Hz during the MC stage is more than that in the frequency band of 125–250 Hz. Further analysis shows that the flexion muscle synergies mostly exist in the frequency band of 140.625–156.25 Hz during the WF stage, and the extension muscle synergies appear in the frequency band of 125–156.25 Hz during the WE stage. These results can help to better understand the time-frequency features of muscle synergy, and expand study perspective related to motor control in nervous system

Analysis of Compositional Variation and Source Characteristics of Water-Soluble Ions in PM2.5 during Several Winter-Haze Pollution Episodes in Shenyang, China

From 18 February to 13 March 2014 and from 17 December 2016 to 27 January 2017, an online analyzer for monitoring aerosols and gases (MARGA) and an online single particle aerosol mass spectrometer (SPAMS) were used to measure and analyze the concentrations and sources of water-soluble (WS) ions in PM10, PM2.5, and gases (NH3, HNO3, HCl), in Shenyang City, China. During the field campaign, nine haze episodes (or smog episodes, total 582 h) were identified, with 960 identified as non-haze periods. The average mass concentrations of PM2.5 and total water-soluble ions (TWSIs) in PM2.5 during haze episodes were 131 μg·m−3 and 77.2 μg·m−3, 2.3 times and 1.9 times the values in non-haze periods, respectively. The average mass concentration of TWSIs in PM2.5 was 55.9 μg·m−3 (accounting for 55.9% of PM2.5 mass loading), 37.6% of which was sulfate, 31.7% nitrate, 20.0% ammonium, 6.6% chloride, 1.9% potassium, 1.4% calcium, and 0.8% magnesium throughout the campaign. Concentrations of sulfate, nitrate, and ammonium (SNA) secondary pollution ions increased rapidly during haze episodes to as much as 2.2 times, 3.0 times, and 2.4 times higher than during non-haze periods, respectively. Diurnal variations during non-haze periods were significant, while complex pollution was insignificant. Based on changes in the backward trajectories and concentrations of WS ions, the hazy episodes were divided into three types: complex, coal-burning, and automobile exhaust pollution. All complex episodes had high concentrations and greater contributions of ammonium nitrate from complex and automobile exhaust pollution, while the contribution of ammonium sulfate from coal-burning pollution was greater than that of ammonium nitrate. The correlation coefficients among SNA species were very high in complex pollution, with nitrate and sulfate the main forms present. The results of principal component analysis (PCA) were related to emissions from burning coal for heating and from long-range transmission in winter. In the case of exhaust pollution, NO3− accounted for the highest percentage of PM2.5, and NH4+ was more closely related to NO3− than to SO42−. Coal-burning pollution was the most common type of pollution in Shenyang. The contribution of sulfate was higher than that of nitrate. Based on PCA, the contribution of coal-burning emissions varied from 36.7% to 53.6% due to industry, soil sources, and other factors

Experiment on the effects of oligo-alginate elicitation on juvenile and adult sporophytes of Saccharina japonica and Saccharina latissima

We here present data underlying a pilot study that investigated the effects of oligo-alginate elicitation on juvenile and adult sporophytes of Saccharina japonica cultivated in China and on adult sporophytes of Saccharina latissima cultivated in Germany. In two consecutive years, treatment with oligo-alginate clearly reduced the detachment of S. japonica juveniles from their substrate curtains during the nursery stage in greenhouse ponds (see data underlying Figure 1 https://doi.pangaea.de/10.1594/PANGAEA.896660). Oligo-alginate elicitation also decreased the density of endo-bionts on sporophytes of S. latissima that were cultivated on sea-based rafts (data underlying figure 3 https://doi.pangaea.de/10.1594/PANGAEA.896662). However, the treatment increased the susceptibility of kelp adults to settlement of epi-bionts (barnacles in Germany [data underlying figure 3 and data underlying figure 4 https://doi.pangaea.de/10.1594/PANGAEA.896662, https://doi.pangaea.de/10.1594/PANGAEA.896663] and filamentous algal epiphytes in China [data underlying figure 2 https://doi.pangaea.de/10.1594/PANGAEA.896661]). In addition, oligoalginate elicitation accelerated the aging of S. japonica adults [data underlying figure 2 https://doi.pangaea.de/10.1594/PANGAEA.896661]