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In the wake of the COVID-19 outbreak, China implemented emergency epidemic prevention and control measures, which played a positive role in economic and social development as well as the containment of the epidemic. Based on stock trading data from February 2020 to December 2022, this paper examines the impact of these measures on the stock returns of A-share listed companies. The findings of the study indicate that social distancing and health measures generally increase stock market returns, despite the varying magnitude of their effects. In addition, the analysis of two aspects, namely the listed sectors and the industry response analysis, further corroborates the main conclusion that social distancing policies have a more pronounced effect on the stock market. The study helps investors understand how the stock market responds to government announcements and enables policymakers to further explore the impact of policy responses during major public health events and their influence on economic and social welfare. [ABSTRACT FROM AUTHOR]

A new species Sinosenecio yangii D.G. Zhang & Q. Zhou (Asteraceae, Senecioneae) from Guizhou Province, China, is described and illustrated based on its morphological characteristics and molecular evidence. It closely resembles S. confervifer and S. guangxiensis, the former in the scapigerous habit and smooth and glabrous achene surface, the latter in the calyculate involucre and purple abaxial leaf surface, and both in the shape and indumentum of leaf lamina, but differs markedly from the latter two in having fewer capitula and epappose achenes. Phylogenetic analysis based on nrITS and ndhC-trnV sequences shows that this new species belongs to the S. latouchei clade and is sister to S. guangxiensis with moderate support. [ABSTRACT FROM AUTHOR]

Osteoporotic fractures, also known as fragility fractures, are prevalent in the elderly and bring tremendous social burdens. Poor bone quality, weak repair capacity, instability, and high failure rate of internal fixation are main characteristics of osteoporotic fractures. Osteoporotic bone defects are common and need to be repaired by appropriate materials. Proximal humerus, distal radius, tibia plateau, calcaneus, and spine are common osteoporotic fractures with bone defect. Here, the consensus from the Osteoporosis Group of Chinese Orthopaedic Association concentrates on the epidemiology, characters, and management strategies of common osteoporotic fractures with bone defect to standardize clinical practice in bone repair of osteoporotic fractures. [ABSTRACT FROM AUTHOR]

The eastern Liaoning Province of China has rich morphological diversity in walnut fruit, which is beneficial for selecting promising characters for marketability purposes. However, only a few reports have addressed morphological diversity in this region. In this study, J. mandshurica nuts and kernels from six geographical provenances were assessed for morphological traits, such as nut longitudinal diameter, nut lateral diameter, nut transverse diameter, mean diameter, nut weight, kernel weight, shell thickness, nut sutural thickness, kernel percentage, and index of roundness. Morphological traits proved to be quite variable and showed differences both within and among the geographical provenances. The frequency distribution of the traits had single peaks and followed a normal distribution. Principal component analysis revealed that 81.062% of the total variance was explained by the first three components. An unweighted PGM with averaging cluster analysis divided the geographical provenances into two groups; cluster I, containing five geographical provenances, and cluster II, containing only one. The study highlighted that the traits related to nut weight were of importance for discrimination, and Fushun is the optimal geographical provenance for breeding and selection. This study could provide a basis and reference for further understanding of the genetic resources of Juglans mandshurica fruit types. [ABSTRACT FROM AUTHOR]

An innovatory approach for determining grinding media ratio and sizes to optimize fraction compositions of grinding products was created based on the principle of grinding dynamics by the single fraction tests, which were conducted with the ore from Yongping Copper mine (China) in a discontinuous conical ball mill (D × L 360 × 160 mm, China), and the results show that the optimal ball size for +8 mm fraction, −8 + 5 mm fraction, −5 + 0.45 mm fraction and −0.3 + 0.2 mm fraction are Φ70 mm, Φ60 mm, Φ50 mm and Φ30 mm, respectively. Furthermore this approach was supported from the point of view of collision energy between ore and media by discrete element method (DEM), wtih results illustrating that the materials are more active with the highest tangential collision energy with 2.23 J. In addition, the comparable tests of the full fraction feed were conducted with media system determined by this method, with the grinding technical efficiency 71.71%, being 7.61 and 1.63 percentage points higher than that under the scheme on site and the other scheme. Furthermore, applicability and feasibility were proved to be tremendously positive through the industrial tests, and results of industrial tests show that unit media consumption and unit energy consumption are reduced by 0.56 kW·h and 0.072 kg/t, respectively, what's more, not only the production capacity is promoted by 1.04 t/h, but also concentrate indexes are also improved with grade and recovery being increased by 1.01 and 2.61 percentage points compared with that before the test. This method is extremely promising and novel and could be used in most beneficiation plants to optimize the media system of ball mill to elevate indexes and promote production in all probability. [Display omitted] • An approach, for determining grinding media ratio and size, based on grinding kinetics was created. • The energy consumption, such as unit power and media consumption, was saved. • The grinding efficiency and the production capability was enhanced. • The concentrate indexed, the grade and recovery of concentrate were improved. [ABSTRACT FROM AUTHOR]

To study and model changes in the development of pak choi (Brassica rapa ssp. chinensisMakino), three pak choi cultivars--Xinxiaqing No. 5 (Xinxiaqing 5), Haiqing, and Huawang--were grown in a modern greenhouse. Four structural parameters, including leaf length, leaf width, and plant height and width, were measured regularly every 3 days. The results showed that the changes in plant height and width, and leaf length and width of the three cultivars followed sigmoidal trends. Logistical regression models {Y = K/[1 + (K - L0)/L0 × exp(-r × t)]; Y = K/[1 + (K - L0)/L0 × exp(2r × rad)]} of the leaf length and width accumulated with growth days and with accumulated radiation fit the actual data very well, with the correlation coefficient R² all greater than 0.98. The R² values of the plant width accumulation models were all greater than 0.93, whereas the R2 values of the plant height regression models were not robust. In this study, the regression models of changes in plant height and width, and leaf length and width of pak choi were used to study the changes of morphological characteristics and analyze the change rules of pak choi growth and development. [ABSTRACT FROM AUTHOR]