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Copper has become one of the most important heavy metal pollutants in the environment because of its wide application and high toxicity, but research on water quality criteria (WQCs) on copper is limited, especially the derivation of seawater WQC. In addition, the toxicity of copper in the seawater system is affected by various environmental factors. Therefore, establishing a WQC that meets the characteristics of the regional environment is a top priority. The correlations between four factors of temperature, salinity, pH, dissolved organic carbon (DOC) and the toxic effect values of copper were analyzed in this study, and the temperature was determined as the most influential factor among the four factors in the Bohai Sea. A specific correlation between temperature and the toxic effects of copper was identified, and WQCs were derived based on the identified correlation and the variations of the Bohai Sea's temperature in different seasons by species sensitivity distribution (SSD) method. Under the condition of the winter, spring, autumn, and summer with an average water temperature of 0.09, 15.96, 17.83, and 24.87 °C, the obtained short-term water quality criteria (SWQCs) were 44.29, 4.70, 4.31, and 3.33 μg/L; the long-term water quality criteria (LWQCs) were 18.14, 1.93, 1.77 and 1.36 μg/L. The findings indicated the importance of introducing specific environmental conditions during the derivation process. This work could provide valuable information for pollution prevention and aquatic life protection in the Bohai Sea and provide a valuable reference for the derivation of criteria in other regions alike.

The design of "data structure" online teaching platform is described in detail based on the character and requirements of "data structure" course. We discuss the choice of development tools, system architecture, and function module designs for the design of the platform. The design and use of this learning platform will improve inefficiency of traditional classroom teaching, and provide a tool to help students' self-learning and cultivate innovative spirit.

This paper is states that training the students’ ability, combine with the course characters of the C programming language, and from the system of practice teaching, advance design of the content, the methods of practice teaching practice to do the deep exploration, the teaching effect is significant .

Methods currently used for the quantitative determination of total lipids and fatty acid composition in plant require solvent extraction. This study examined the solvent extraction of purple medic seed oil. Results varied with different extraction conditions. The effects of temperature, extraction time, sample size and solvent type on the extraction efficiency and oil quality were studied. The amount of extract collected was highest when ether absolute was used as a solvent for solvent extraction.

Trichoderma reesei (teleomorph Hypocrea jecorina) is an industrially important filamentous fungus for glycoside hydrolases production, with its xylanolytic enzymes widely applied in many areas. However, the molecular mechanisms underlying xylanase expression are still insufficiently understood. In particular, the effect of sugar transporter on the induction of xylanase expression is unclear. In this work, we identified a novel major facilitator transporter TrSTR1 that is capable of transporting xylose by using a xylose utilization system in Saccharomyces cerevisiae. In T. reesei, TrSTR1 is essential for the utilization of d-xylose, l-arabinose, and even their downstream metabolites D-xylitol and L-arabitol. TrSTR1 is also involved in the induction of xylanase expression since both the xylanase activity and extracellular protein concentration in the Tu6△str1 strain were decreased, which further confirmed by a qRT-PCR analysis of the transcript levels of the key transcriptional regulators. Our observations provide new insights into connections between pentose utilization and xylanase production in T. reesei.

Consider the weighted p(t)-Laplacian ordinary system {-(w(t)|u'(t)|p(t)-2u'(t))' + w(t)f(t,u(t)) = 0 in (a,b), u(a) = u(b) = 0, where f ∈ C([a,b] × RN,RN), w∈C([a,b],R), p∈C([a,b],R) and p(t) > 1 for t ∈[a,b]. It is proved that if ∃R > 0 such that 〈f(t,u),u〉 ≥ 0, ∀t∈[a,b], ∀u∈RN with |u| = R, then the problem has a solution u such that |u(t)| ≤ R for t ∈ [a, b]. As a corollary of this result, taking w(t) = tn-1, we obtain the existence of the radial solutions for the elliptic systems. Our result generalized the corresponding results obtained by Hartman and Mawhin.

It is quite difficult to isolate total RNA from Aquilaria sinensis due to the complexity of its secondary metabolites. In order to obtain the high-quality RNA, we investigated sampling method and RNA extraction from both normal and agilawood tissues of the plant.Five methods such as modified CTAB-LiCl method, modified CTAB-LiCl method with no water-bath, SDS-acid phenol method, modified guanidinium thiocyanate-CTAB method and EASYspin RN09 RNA isolation kit were used to extract RNA from leaves, branches, white wood samples, agilawood samples of A. sinensis, respectively.Total RNA was stable for 5 hours at room temperature after extracted from A. sinensis branches. EASYspin RN09 RNA isolation kit was the best extraction method for the leaf while modified guanidinium thiocyanate-CTAB method was the best for the other samples.A great quantity of RNAs can be isolated from samples of white wood and agilawood wood, respectively. Their ratios of 28S : 18S are in the range of 1.2 - 1.4 and RINs are between 6.8 - 7.5. These RNAs can be applied in transcriptome sequencing.