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English writing is gaining more attention in all stages of English teaching. However, teaching in Chinese senior high school is not satisfactory, and consequently, students are bored of learning. Hence, this study aims to explore what factors repress high school students from learning English writing. Motivation is the key to success in English learning. Therefore, inspiring students’ learning motivation is of great importance in guiding English writing teaching. This study first discusses the meaning and types of motivation, analyzes the role of motivation in English writing learning, and proposes strategies in the background of the new curriculum standards based on modern educational theory. The findings suggested that making students understand the social value of English writing and helping them to set appropriate learning goals can lead them to have more impetus for English writing learning. Moreover, the findings reinforced the importance of task-based learning strategies to stimulate students’ interest in learning. Also, using student feedback correctly to improve teachers’ assessment strategies and carrying out extracurricular activities helps reinforce and supplement knowledge, enabling students to stay motivated to learn English writing.

With the rapid development of internet technology, online shopping has brought great convenience to people’s lives. As an impartment group of online consumption, college students bring a large amount of express packaging waste. However, colleges and universities lack an effective express packaging recycling mechanism, which results in a double waste of economic and environmental benefits. We collected relevant data from some universities in Wuhan through interviews and questionnaires, and analyzed consumers wishes, express packaging disposal measures and influencing factors through Logistic regression and SWOT methods. Finally, it summarizes the existing problems in the recycling and utilization of express packaging in colleges and universities in Wuhan and puts forward feasible suggestions. We have proposed an efficient dual-track express packaging recycling system for colleges and universities, which includes an information platform and smart recycling boxes to achieve environmental protection and recycling, and it is expected to be promoted in the whole society.

Background Hemicellulose acts as one factor contributing to the recalcitrance of lignocellulose that prevents cellulases to degrade the cellulose efficiently even in low quantities. Supplement of hemicellulases can enhance the performance of commercial cellulases in the enzymatic hydrolyses of lignocellulose. Kluyveromyce marxianus is an attractive yeast for cellulosic ethanol fermentation, as well as a promising host for heterologous protein production, since it has remarkable thermotolerance, high growth rate, and broad substrate spectrum etc. In this study, we attempted to coordinately express multiple hemicellulases in K.marxianus through a 2A-mediated ribosome skipping to self-cleave polyproteins, and investigated their capabilities for saccharification and ethanol production from corncobs. Results Two polycistronic genes IMPX and IMPαX were constructed to test the self-cleavage of P2A sequence from the Foot-and-Mouth Disease virus (FMDV) in K.marxianus. The IMPX gene consisted of a β-mannanase gene M330 (without the stop codon), a P2A sequence and a β-xylanase gene Xyn-CDBFV in turn. In the IMPαX gene, there was an additional α-factor signal sequence in frame with the N-terminus of Xyn-CDBFV. The extracellular β-mannanase activities of the IMPX and IMPαX strains were 21.34 and 15.50 U/mL, respectively, but the extracellular β-xylanase activity of IMPαX strain was much higher than that of the IMPX strain, which was 136.17 and 42.07 U/mL, respectively. Subsequently, two recombinant strains, the IXPαR and IMPαXPαR, were constructed to coordinately and secretorily express two xylantic enzymes, Xyn-CDBFV and β-D-xylosidase RuXyn1, or three hemicellulolytic enzymes including M330, Xyn-CDBFV and RuXyn1. In fed-batch fermentation, extracellular activities of β-xylanase and β-xylosidase in the IXPαR strain were 1664.2 and 0.90 U/mL. Similarly, the IMPαXPαR strain secreted the three enzymes, β-mannanase, β-xylanase, and β-xylosidase, with the activities of 159.8, 2210.5, and 1.25 U/mL, respectively. Hemicellulolases of both strains enhanced the yields of glucose and xylose from diluted acid pretreated (DAP) corncobs when acted synergistically with commercial cellulases. In hybrid saccharification and fermentation (HSF) of DAP corncobs, hemicellulases of the IMPαXPαR strain increased the ethanol yield by 8.7% at 144 h compared with the control. However, both ethanol and xylose yields were increased by 12.7 and 18.2%, respectively, at 120 h in HSF of aqueous ammonia pretreated (AAP) corncobs with this strain. Our results indicated that coordinate expression of hemicellulolytic enzymes in K. marxianus promoted the saccharification and ethanol production from corncobs. Conclusions The FMDV P2A sequence showed high efficiency in self-cleavage of polyproteins in K. marxianus and could be used for secretory expression of multiple enzymes in the presence of their signal sequences. The IMPαXPαR strain coexpressed three hemicellulolytic enzymes improved the saccharification and ethanol production from corncobs, and could be used as a promising strain for ethanol production from lignocelluloses.

At present, the existing power mechanical gasoline engine fire pump is prone to large vibration during operation. Due to the lack of protection structure, long-term vibration will shorten the service life of the fire pump. Meanwhile, the upper end of the fire pump body is usually not set up with a protective structure, which is easily damaged by the extrusion and impact of objects. Therefore, a new type of protection device is designed in this paper, which plays a protective role by setting a relevant absorber at the lower end of the fire pump body, and at the same time, a buffer pad is arranged at the upper end of the cover to have the effect of buffering and shock absorption. To this end, this device has the function of reducing the damage to the fire pump body caused by the impact of heavy objects, improving the performance of the existing fire pump, and prolonging its service life.

UGD gene encodes UDP-glucose dehydrogenase (UGD) which is a key enzyme in the biosynthesis of cell wall, and it catalyses the irreversible oxidation of UDP-glucose (UDP-Glc) into UDP-glucuronic acid (UDP-GlcA). In cucumber, the expression level of CsUGD2 genes was higher in phloem tissues of pedicel and fruit than that in stalk. This study investigated the function of CsUGD2 in cucumber by different methods. Structure analysis indicated that CsUGD2 gene only has an exon with a length of 1,443 bp. Protein alignment suggested that UGD protein was highly conservative in different species. Phylogenetic analysis showed that CsUGD2 protein and CmoUGD2 protein form a same clade which is far away from UGDs in Arabidopsis . Real-time fluorescence quantitative analysis of CsUGD2 in different tissues of cucumber in the same period showed that CsUGD2 expressed highest in the root of cucumber. When we transformed CsUGD2 into wild type Arabidopsis , the roots of transgenic plants were shorter and the flowering time was delayed. These results suggested that CsUGD2 may play an important role in the development of cucumber roots and only act on the development of cucumber fruit when compared with other plants fruits. However, the role of CsUGD2 in regulating the growth and development process of cucumber need to further study. ********* In press - Online First . Article has been peer reviewed, accepted for publication and published online without pagination. It will receive pagination when the issue will be ready for publishing as a complete number ( Volume 47, Issue 1, 2019 ). The article is searchable and citable by Digital Object Identifier (DOI). DOI number will become active after the article will be included in the complete issue.

With the sudden outbreak and rapid spread of COVID-19, global economic development and social stability have been seriously affected. The virus mainly spreads infection among people on a large scale through the air. People are gradually focusing on how to use HVAC system, so that it can play a more efficient and positive role in epidemic prevention and control. Consequently, we designed an intelligent purification and disinfection apparatus for air-conditioning units. The apparatus integrates rapid virus detection and high-efficiency disinfection functions. It uses a modular design and different operating modes for different levels of epidemic periods. This apparatus is not only suitable for daily life, but also can meet the prevention and control requirements during the epidemic period, which takes the economy, energy saving, and environmental protection into account.

Wearable devices such as smartwatches have become popular. The accelerometer embedded in smartwatch can record the movement of hand, so that it may lead to privacy compromise when performing sensitive inputting on keyboard with hand wearing smartwatch. The existing inference attack collects smartwatch's accelerometer readings which correspond to the movement of hand when inputting a numeric password, then the inputted password can be inferred by applying classification and inference algorithm to the readings. However, there are two drawbacks in existing inference attack model. Firstly, the sample set is too large, but the attacker is difficult to access large-scale sample data in practice. In addition, the scale of candidate set of possible passwords is sometime too large. Aiming at the two drawbacks of existing inference attack, the optimized attack model proposed in this paper has introduced a correction process and a new inference algorithm. The experiment results show that the optimized attack model can effectively recognize victim's inputted numeric password with small samples and the scale of candidate set is relatively small.

Taking the Northwest Loess Plateau of Qianyang County and Xunyi County as the research object, its subordinate 4 administrative villages were investigated. The production and component of rural domestic waste as well as current situation of disposal were analyzed. Solutions have been proposed to solve the existence questions of current waste treatment process. Considering the geography, climate, economic and other factors, and using a variety of treatment methods, the economy with low cost and high maneuverability life garbage disposal model was raised for the same loess landform characteristics of northwest rural area.