With the rapid economic growth, the concept of digital economy and sustainable development has gradually become the main task facing our country. This paper constructs the evaluation system of the development level of digital economy and the comprehensive index of regional sustainable development by the entropy weight method, uses the two-way fixed effect model to explore the influence mechanism of digital economy on the sustainable development of the Yangtze River Delta region.
This study aims to explore the design and application of a learning achievement evaluation model, in order to improve the quality of teaching in the field of education and promote student development. This article starts with the importance of constructing a learning effectiveness evaluation model, and then clarifies the basic concepts and related theories of learning effectiveness evaluation, providing theoretical support for subsequent model design. In the model design section of learning effectiveness evaluation, propose the model design principles, indicator selection, and construction process to ensure the accuracy and comparability of the evaluation model construction. In the application and evaluation section of the learning effectiveness evaluation model, the application and evaluation methods of the main models in practical teaching were explored. Finally, the issues that need to be noted in the design process of the evaluation model were proposed in order to design a more high-quality evaluation system and promote the improvement of education quality.
Plum (Prunus domestica) is a seasonal nutraceutical fruit rich in many functional food nutrients such as vitamin C, antioxidants, total phenolic content, and minerals. Recently, researchers have focused on improvised technologies for the retention of bioactive compounds during the processing of perishable fruits; plum is one of these fruits. This study looked at how the percentage of moisture content and percentage of acidity were affected by conventional drying and osmotic dehydration. Total phenolic content (mg GA/100 g of plum), total anthocyanin content (mg/100 g), and vitamin C (mg/100 g) Conventional drying of fruit was carried out at 80.0 ℃ for 5 h. At various temperatures (45.0 ℃, 50.0 ℃, and 55.0 ℃) and hypertonic solution concentrations (65.0 B, 70.0 B, and 75.0 B), the whole fruit was osmotically dehydrated. It was observed that the osmotically treated fruit retains more nutrients than conventionally dried fruit. The total phenolic content of fruit significantly increased with the increase in process temperature. However, vitamin C and total anthocyanin content of the fruit decreased significantly with process temperature, and hypertonic solution concentration was observed. Hence, it was concluded that osmodehydration could be employed for nutrient retention in plum fruit over conventional drying. This process needs to be further refined, improvised, and optimised for plum processing.
The present study demonstrates the effect of direct solar drying (DSD) and hot air drying (HAD) on the quality attributes of Fuji apple slices. DSD samples took a longer time (150–180 min) to dry and simultaneously reached higher equilibrium moisture content at the end of rehydration than HAD samples. DSD samples have higher rehydration ability, dry matter holding capacity, and water absorption capacity than HAD samples. Among several empirical models, the Weibull model is the best fit with higher R2 (0.9977), lower root mean square (0.0029), and chi-square error (0.0031) for describing the rehydration kinetics. Rehydrated HAD samples showed better color characteristics than DSD in terms of overall color change, chroma, and hue angle values. Whereas the hardness and chewiness of rehydrated DSD samples were better than HAD samples because of higher dry matter holding capacity in DSD. Apart from color retention, the DSD samples showed better rehydration capacity and a good texture upon rehydration than HAD slices.
Beta macrocarpa, Guss is an interesting species showing very low germination rates. The leading objectives of this work were to investigate the dormancy mechanism and to find methods to break dormancy in order to achieve rapid, uniform and high germination. Macro and micro-morphologic analyses were performed by stereo microscopy and scanning electron microscopy showed two fruit coats. The yellow external coat or persistent perianth coat (PPC) was accrescent with 5 erect segments contiguous to the operculum of the seed capsule. This coat forms spongy layers (50 to 300 µm thick) that could be eliminated manually. The narrow internal coat or pericarp or achene coat (AC) forms woody joined seed capsules, each presenting a pressed operculum that cannot be manually opened. This coat was not adherent to seeds and was composed of compressed cells (50 to 200 µm thick) which form pockets for salt cristal. Seeds were lentiform (1 to 2 mm diameter and 0.5 to 0.8 mm thick) and highly fragile. The embryo was whitish surrounded peripherally by the perisperm with two highly developed cotyledons and radical. Polyphenol concentrations in both coats showed that after 4 months of collection, total polyphenol concentrations were 4-fold higher in the pericarp than in the persistent perianth. However, after one year, this parameter decreases significantly in the pericarp, whereas, it increases to a larger extent in the perianth. Different germination tests indicated that the pericarp provides a chemical and a physical resistance to seed germination during the first 4 months of the experiment after collection. The chemical dormancy was released to higher levels of total polyphenol compounds that inhibited seed germination and seedling growth. However, the physical dormancy was associated with the hardness of this intern coat which caused a mechanical resistance to radicle emergence. After one year of storage, total polyphenol pericarp concentration decreased notably, and chemical resistance disappeared, whereas the physical one persisted. Consequently, one year of storage pericarp removal is sufficient to break this exogenous dormancy.
Copyright © by EnPress Publisher. All rights reserved.