Returns to scale in the production of selected manufacturing sectors in China

AbstractIn the study on economic growth, international trade and economic geography, making different assumption on returns to scale may lead to stark difference in both theoretic conclusion and policy implication. A very important assumption supporting literatures in New Economic Geography is that production of manufacturing sector is characterized by increasing returns to scale. Around this assumption, much debate exists. There is no predominant conclusion from empirical study either. This study begins with a brief survey of the study on the assumption of returns to scale. Based on data from 17 selected sectors in manufacturing industry in China and using Diewert-Fox Model[1], returns to scale in the production of selected sectors in manufacturing industry in China is investigated. It is found that all of the selected sectors in manufacturing industry in China show increasing returns to scale, and most of those sectors experience modest negative or zero technical change, which implies that economic growth in Chinese manufacturing industry over the recent two decades has largely been driven by increasing returns to scale rather than technical progress

State diagram of spin-torque oscillator with perpendicular reference layer and planar field generation layer

The state diagram of spin-torque oscillator (STO) with perpendicular reference layer (REF) and planar field generation layer (FGL) was studied by a macrospin model and a micro-magnetic model. The state diagrams are calculated versus the current density, external field and external field angle. It was found that the oscillation in FGL could be controlled by current density combined with external field so as to achieve a wide frequency range. An optimized current and applied field region was given for microwave assisted magnetic recording (MAMR), considering both frequency and output field oscillation amplitude. The results of the macro-spin model were compared with those of the micro-magnetic model. The macro-spin model was qualitatively different from micro-magnetics and experimental results when the current density was large and the FGL was non-uniform

Evaluating and Analyzing Urban Renewal and Transformation Potential Based on AET Models: A Case Study of Shenzhen City

With the development of the urban economy and population growth, the demand for urban construction land continues to rise. Addressing the challenges of land protection and ecological security calls for the exploration of new approaches. This study emphasizes a sustainable solution by emphasizing in-depth exploration of existing land resources, moving away from the traditional “expanding the pie” model of urban development. Specifically, we selected land parcels in Shenzhen city from 2010 to 2020 that met the criteria for urban renewal and transformation as evaluation units, further categorized into residential, industrial, and commercial land for transformation. From multiple perspectives, including geological conditions, building conditions, agglomeration, social factors, and the degree of completeness of public facilities, we constructed an evaluation system comprising 23 indicators to quantify the potential for urban renewal of these units. Through the AET (AHP-EWM-TOPSIS) model analysis for assessing the potential of urban renewal and transformation, we classified the transformation parcels into different potential levels based on the optimized solutions from the model. Finally, we validated the results using the planned land units implemented in Shenzhen from 2010 to 2020, achieving an accuracy of 81% in matching the spatial distribution of potential levels with the actual situation. The comprehensive evaluation results from the model provide a basis for optimizing and enhancing sustainable urban renewal. This research contributes to the formulation of informed decisions and strategic urban development planning, enabling a more cautious and resource-efficient approach to address the challenges of urban expansion

Therapeutic and immunoregulatory effects of water-soluble alkaloids E2-a from Sophora moorcroftiana seeds as a novel potential agent against echinococcosis in experimentally protoscolex-infected mice

Abstract Novel compounds and more efficient treatment options are urgently needed for the treatment of cystic echinococcosis (CE), which is caused by Echinococcus granulosus. The decoction of Sophora moorcroftiana (Fabaceae) has been used to treat parasitosis for years in traditional Tibetan medicine. The aim of this study was to screen insecticidal water-soluble alkaloids from S. moorcroftiana seeds and evaluate the therapeutic effects against CE and the immune response induced by the alkaloidal fraction. Low polarity compounds (E2-a) were isolated from water-soluble alkaloid (E2) and matrine and sophocarpine were identified as major components. The E2-a fraction was more effective against protoscoleces than other constituents from S. moorcroftiana. After 20 weeks of secondary infection with protoscoleces, mice were orally treated with E2-a (100 mg/kg/day) for 6 weeks to evaluate therapeutic and immunoregulatory activities. Compared with the untreated group, E2-a treatment induced a significant reduction in cyst weight (mean 2.93 g) (p < 0.05) and an impaired ultrastructural modification of the cyst. Interestingly, the application of E2-a resulted in a significant increased frequency of CD3+CD4+ T-cell subsets and decreased frequency of CD3+PD-1+ T-cell subsets, compared with protoscolece-infected mice without treatment. The E2-a fraction of S. moorcroftiana can inhibit the cyst development of CE and boost the specific immune response by reducing the expression of PD-1 and accelerate the cytokine secretion of antigen-specific T-cells. All data suggest the E2-a fraction from S. moorcroftiana seeds may be used as a new potential therapeutic option against E. granulosus infection