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[Objective] This study aimed to explore the potential damage of non-grain conversion of cultivated land on soil health, and provide a scientific basis for evaluating the impact of non-grain conversion on land productivity and ecological functions. [Methods] 80 surface soil samples were randomly collected from six types of non-grain conversion land, including facility vegetable field, orchard, poplar forest, grassland, highway landscape forest, and fallow land, and the control farmland in the rural-urban fringe area of Xuzhou City through field survey, sampling analysis, model evaluation, and statistical analysis. A total of 23 indicators of soil physical, chemical, and biological properties, as well as heavy metal pollution were measured to construct the cultivated land health assessment model, to explore the impact of non-grain conversion on land productivity and soil health. [Results] The results show that: (1) Non-grain conversion significantly changed soil physio-chemical and biological characteristics. The activities of cellulose disaccharide hydrolase, alkaline phosphatase, and bacterial diversity index in non-grain conversion soil were significantly lower than those in the soil of the control site (P < 0.05). The soil organic matter content (27.92-36.33 g·kg-1), total phosphorus (0.89-1.54 g·kg-1), available phosphorus (186.82-307.01 mg·kg-1), available potassium (199.09-305.03 mg·kg-1), and total nitrogen and nitrate nitrogen content in facility vegetable plots were the highest, and there were significant differences (P < 0.05) compared to the other five non-grain conversion land use types; (2) Compared to the farmland control site, the six types of non-grain conversion land use have led to some imbalance of different soil functions including productivity, water retention and purification, carbon sequestration, nutrient cycling, and biodiversity, even resulting in a suboptimal health state; (3) The structural equation model fitting result shows that soil nutrients, enzyme activity, biodiversity, and heavy metal pollution index dominated the soil health differentiation of non-grain conversion sites. [Conclusion] Non-grain conversion had an impact on cultivated land health, while there were considerable differences in health damage among different land uses. The results provide some reference for targeted management of non-grain conversion of farmland and safeguarding food security.

Problemistic search literature has long sought to understand which responses firms adopt when addressing performance shortfalls. Studies have typically considered certain responses and focused on established decision rules to examine search directions, thereby, implicitly assuming that all responses considered are workable solutions to performance shortfalls. Conversely, we argue that variations in decision-makers' beliefs about the effectiveness of particular responses in improving firm performance play an important role. These beliefs, alongside evidence supporting them, determine which specific responses firms adopt. To test this argument, we focus on two types of search solutions represented by research and development (R&D) intensity and philanthropic donation intensity. Based on 2009–2018 data collected from publicly listed Chinese firms, we find that, when decision-makers agree on the effectiveness of R&D, the positive relationship between performance shortfalls and R&D intensity strengthens; whereas when they agree on the effectiveness of corporate social responsibility (CSR), the negative relationship between performance shortfalls and donation intensity weakens. The effects of shared beliefs on the effectiveness of R&D and CSR are stronger when they are supported by relevant evidence—that is, when there is a stronger correlation between R&D or CSR on the one hand and firm performance on the other. [ABSTRACT FROM AUTHOR]

Ischemic stroke (IS), usually caused due to an abrupt blockage of an artery, is the leading cause of disability and the second leading cause of death worldwide. The association of the C-reactive protein (CRP) gene (s3093059 T/C and rs1205 C/T) polymorphisms and IS susceptibility has been widely studied, but the results remain inconsistent. Our study aimed to assess the association between CRP gene (s3093059 T/C and rs1205 C/T) polymorphisms and IS risk. PubMed, Embase, Cochrane Library, Web of Science, China National Knowledge Infrastructure, and WanFang databases were searched up to April 2022 to identify eligible studies. The Newcastle-Ottawa scale (NOS) score was calculated to assess study quality. The odd ratios (ORs) with a 95% confidence interval (CI) were calculated to assess the association between CRP gene (rs3093059 T/C and rs1205 C/T) polymorphisms and IS risk. Eighteen case–control studies with 6339 cases and 29580 controls were identified. We found that CRP (s3093059 T/C and rs1205 C/T) polymorphism was not significantly associated with the risk of IS in any genetic model (recessive model: OR 1.00, 95% CI 0.79–1.26; OR 1.06, 95% CI 0.90–1.25). When stratified analysis by country, genotype method, source of controls, and NOS score, still no statistically significant association was found. Our study indicated that the CRP (rs3093059 T/C and rs1205 C/T) polymorphisms were not associated with the susceptibility to IS.

Background: Perform computed tomography (CT) three-dimensional (3D) mapping analysis of the ipsilateral olecranon tip to determine its suitability as an autograft for unrepairable coronoid fractures. Methods: CT was evaluated using Mimics 13.0 and 3-matic software (Materialise, Inc., Leuven, Belgium). Coronoid fracture fragment was measured from the medial sublime tubercle to the halfway point of the proximal radioulnar joint. Ipsilateral olecranon tip graft was measured at the equivalent height of the coronoid fragment and the angle of graft "cut" necessary to match the coronoid fragment was measured. The overall width of each graft site was measured in thirds and the congruity of surface geometry was measured by overlapping both fragments. The ipsilateral olecranon tip lateral facet which rotates to become the coronoid medial facet was also measured. Results: The olecranon tip and coronoid fragments were similar in average maximum height and width. The average angle of graft cut needed to match the coronoid fragment was 86°. The average difference between the medial facet of the coronoid and lateral facet of the olecranon was <2 mm. Discussion: The ipsilateral olecranon tip can be harvested through the same surgical incision and function as a local autograft during reconstruction of unrepairable coronoid fractures. [ABSTRACT FROM AUTHOR]

To reduce the mining of high-grade magnesite and solve the environmental pollution caused by magnesite tailings, magnesite tailings were used to produce MgO expansion agent (MEA), and a detailed study of its performance was carried out in this study. Firstly, the effects of different calcination times on the calcination products, the specific surface area, and the activity of MEA were analyzed. Then, the MEA produced by calcinating at 950 °C for 1 h was taken as the research object, and the effects of its content on the expansion performance, compressive strength, and flexural strength of the mortar were studied. The results showed that the decomposition of magnesite tailings after high-temperature calcination produced MEA, and the longer the calcination time, the lower the activity. The calcined tailings could compensate for the shrinkage of the mortar, and the expansion increased with the increase in curing temperature. What is more, when the content was less than 8%, the hydration of MEA filled the pores and improved the compactness, so the strength of the mortar increased with the increase in the expansion agent content. When the dosage was greater than 8%, excessive expansion increased the porosity, causing harmful expansion of the mortar and damaging its integrity, leading to a decrease in strength. Fly ash reduced the expansion of mortar, and after adding 30% fly ash, the expansion decreased by 20.0–36.1%, and the ability to suppress expansion decreased with the increase in curing temperature. [ABSTRACT FROM AUTHOR]