Subjects: Biology >> Botany >> Applied botany submitted time 2020-08-02 Cooperative journals: 《广西植物》
Abstract：为解决木本切花植物帝萝花‘璀璨明珠’繁殖效率低的问题，以其幼嫩枝芽为外植体，研究不同基本培养基对长势的影响、不同激素种类和浓度对增殖和生根的效果，揭示了‘璀璨明珠’离体繁殖的生长特点，建立了高效的帝萝花‘璀璨明珠’组培快繁技术体系。结果表明：‘璀璨明珠’幼嫩枝芽消毒的方法是0.1%的升汞溶液浸泡12 min，污染率为21.5 %；外植体在WPM+ZT1 mg﹒L-1+NAA0.1 mg﹒L-1培养基上，侧芽萌发率为73%。增殖的最佳培养基为MS + BA0.4 mg﹒L-1 + NAA0.05 mg﹒L-1，增殖系数为6.63，增殖方式为侧芽增殖和植株基部丛生芽增殖; 生根的适宜培养基为MS + IBA 0.75 mg﹒L-1+ NAA 1 mg﹒L-1，生根率70%。生根瓶苗移栽于珍珠岩和细草炭体积比0.5﹕1的基质中，光照强度10 000～12 000 lx，空气湿度70%～80%下培养，60 d 后成活率可达72%。研究结果为帝萝花组培种苗的商业化生产提供了技术支撑，促进了该高档木本切花的推广、种植和产业化。
Subjects: Psychology >> Social Psychology submitted time 2020-03-27
Abstract： In December 2019, an outbreak of a novel coronavirus disease (COVID-19) occurred in Wuhan, Hubei province, China. COVID-19 is characterised by fever and severe acute respiratory symptoms in early stages, which can rapidly progress to acute respiratory distress syndrome that is associated with high mortality. As of 10 February 2020, 37.626 cases have been confirmed and COVID-19 has directly caused 1.016 deaths in China. The wide and rapid spread of COVID-19 has intensely captured public attention, leading to increased mental health stress. Timely mental health care and intervention during the outbreak of COVID-19 is urgently needed not only for confirmed or suspected patients and frontline medical workers, but also for the general public. Previous studies showed that affirmation of personal values can buffer psychological stress responses in various threat situations. The goal of the present study was to investigate whether an intervention involving reflection on personal values was capable of buffering psychological stress responses during the outbreak. We recruited 220 participants who completed a questionnaire on their personal values. Those in the self-affirmation group were asked to choose and write their thoughts and feelings of a personal value that made them feel important to themselves while those in the control condition were asked to do the same for a personal value that they thought was important to others. Both groups completed a Self-rating Anxiety Scale (SAS) and Beck Depression Inventory (BDI) prior to and 7 days after intervention. We used two-way repeated measures analysis of variance (ANOVA) to evaluate the buffer effect of value affirmation on stress responses with time of assessment as a within-subjects factor and intervention group as a between-subjects factor for anxiety and depression. Our results revealed a significant relationship between time and intervention for the reduction of anxiety. Further simple effect analysis demonstrated that the control group showed heightened levels of anxiety 7 days after intervention compared with before, whereas participants who affirmed their values did not show any increase. This effect remained significant after controlling for sex, age, educational level, and annual family income. However, no significant differences were found for depression. The present study demonstrates for the first time that an experimental intervention involving the affirmation of personal values can buffer psychological stress response during the COVID-19 epidemic. Specifically, participants who affirmed their values did not show increased levels of anxiety compared with control participants. Self-affirmation is easy to accomplish since it does not require professional guidance or a distinct environment and occupies little time, it would be a convenient strategy for the public to cope with psychological stress during the outbreak.
Subjects: Psychology >> Cognitive Psychology submitted time 2020-01-03
Abstract： Reading comprehension is one of the most complex behaviors that we engage in on a regular basis. Decoding and language comprehension are two important components of reading comprehension. While up to now, little research has been devoted to directly explore the effects of phonological memory and central executive function on diverse reading comprehension components (decoding and language comprehension). In addition, the primary school stage is a critical period of development of children's reading ability and cognitive ability. However, few research has focused on the developmental changes in the relationship of phonological memory, central executive function and reading comprehension among children in different grades. Therefore, the purpose of this study is to examine the contribution of phonological memory and central executive function on decoding and language comprehension of children in different grade levels. Two hundred and fifty-six children completed Chinese Characters Reading, Chinese Word Reading, and Pseudo-Word Reading to investigate decoding ability, as well as a Listening Comprehension Test to exam language comprehension. Additionally, we used Digit Span and Non-word Span to measure children's phonological memory, and GO/NOGO task, Stroop task, Digit updating task and Digit shifting task to investigate children's central executive function. Correlation analysis and structural equation models (SEM) were used to investigate the effects of phonological memory and central executive function on decoding, language comprehension of children in different grades. Results indicated that, the effect of phonological memory and updating on decoding were significant. Also, the effect of updating and shifting on language comprehension were significant. On further analysis, we divided the four grades into two levels based on the reading stage theory, that third grade and fourth grade as one level, fifth grade and sixth grade as another level. In the third grade and fourth grade level, phonological memory and updating accuracy contributed to decoding. Moreover, updating accuracy and shifting cost predicted language comprehension. In the fifth grade and sixth grade level, only the effect of updating on decoding was significant.The results indicated that, the prediction of phonological memory on decoding disappeared as children progress through school. More importantly, we found that updating had a relatively stable contribution to decoding across grade levels. It revealed that different functions of working memory played different roles in reading, which seem that not all cognitive abilities are equally important in the reading process. Furthermore, phonological memory and central executive function produced different predictive effects in decoding and language comprehension as the grades grew. "
Subjects: Biology >> Botany >> Applied botany submitted time 2018-10-26 Cooperative journals: 《广西植物》
Abstract： Rhododendron is a world famous ornamental garden plant and has significant economic and ornamental value. Light has an important impact on the growth and development of Rhododendron. However, the studies on the demand and adaptability of Rhododendron are scarce. In order to understand the demand and adaptability of Rhododendron to light, 3-year-old plants of Rhododendron ‘Furnivall′s Daughter’ were used as materials and the effects of shading on leaf anatomical structure and photosynthesis were studied. The results showed that: the impact of light intensity on the stomata density of Rhododendron ‘Furnivall′s Daughter’ is not obvious, and the stomatal density ranged from 299.70 to 327.22 mm-2 . However, the stomatal size and the area of stomata apparatus were significantly influenced by light intensity. The plants of 100% and 30% full light intensity had the minimum and maximum stomatal size, respectively. As the light intensity decreased, the thickness of leaf, palisade tissue, sponge tissue, as well as the thickness of adaxial epidermis and abaxial epidermis decreased to improve the light use efficiency of leaves. The plasticity analysis showed that the plasticity index of mesophyll-related parameters such as leaf thickness, abaxial epidermis thickness, and the thickness of palisade and spongeb tissue were higher, while that of stomatal-related parameters such as stomatal density, stomatal length and width were lower, which indicated that mesophyll tissue plays a more important role in the process of adaption to different light environment. The analysis of light response curves and photosynthetic parameters showed that the plants of 100% full light intensity were inhibited and damaged by strong light, and the plants showed the lowest light saturation point (LSP), net photosynthetic rate (Pn), photosynthetic rate at light saturation point (Pmax), stomatal conductance (Gs) and transpiration rate (Tr). After shading treatments, the Pn, Pmax, Gs, Tr and light use efficiency (LUE) were improved. Compared with other shading treatments, the plants of 30% full light intensity not only had the lowest light compensation point (LCP), dark respiration rate (Rd) but also had the highest LSP, Pn, Pmax, Gs, Tr and LUE. The above results suggest that the optimum light intensity of Rhododendron ‘Furnivall′s Daughter’ in Kunming is about 30% full light intensity. In the cultivation and application of Rhododendron, we should take some shading measures to meet the optimum light conditions for its growth
Hits
Hits
Downloads
Comment