In order to analyse the gender disparities in scientific research output in the field of economics, this paper selected the Web of Science database as the source database. We collected and screened ...257,642 articles written by 130,397 authors from 1933 to 2017 in the field of economics. In this study, we use mathematical statistics and bibliometrics indexes to quantitatively analyse the gap between male and female authors in many aspects, including the output and influence in different level of journals and institutions, the dynamic evolution of output and influence and collaboration modes with gender disparities. In addition, we have analyzed the disparities in output and influence of male and female authors among different countries. The results show that male authors dominate in the economics research field according to their high output and influence. However, female authors also show advantage when it comes to the research influence. Finally, we conducted a dynamic analysis of the contribution and collaboration of men and women over the course of their careers, and our findings again demonstrate the importance of women’s participation in scientific collaboration. This study can provide an insight of gender different in economics research.
The aging residential reconstruction has become an important influence factor of people's livelihood and economic development in Northeast China. In order to better meet the requirements of the aging ...transformation of Northeast China, this paper proposes a virtual three-dimensional model construction method based on this mobile communication technology. The design of residential aging adaptation transformation is the process of transforming and updating the original buildings. It is also one of the means of modern building energy saving. With the continuous development of virtual three-dimensional model, based on the regional characteristics of Northeast China, this paper puts forward the design idea of virtual three-dimensional model for aging transformation of residential buildings in Northeast China, which makes up for the deficiency of virtual three-dimensional model technology in the original building facade reconstruction design. This paper improves the old-age transformation method of the northeast area, makes it more concise and real, and improves the efficiency of the aging suitable transformation of the northeast area.
Plant height is an important grain yield-associated trait in maize. To date, few genes related to plant height have been characterized in maize. To better understand the genetic mechanisms of plant ...height in maize, we revealed the transcriptional changes of three dwarf mutants compared to the wild type. By ethyl methane sulfonate treatment of the wild-type maize cultivar PH6WC, we obtained three dwarfs—PH6WCdwarf1 (pd1), PH6WCdwarf2 (pd2), and PH6WCdwarf3 (pd3)—and their plant heights were reduced by 42%, 38%, and 24%, respectively. RNA-Seq data suggested that 1641 differentially expressed genes (DEGs) overlapped with each other among the three dwarfs at the seedling stage. Further analysis showed that the DEGs were divided into four groups with different expression patterns. Functional analysis revealed that these DEGs were commonly enriched in 47 GO terms mainly involved in cytokinesis, hormone, and energy metabolism pathways. Among them, An1, involved in the GA biosynthesis pathway, and mutations in An1 result in reduced plant height. EREB182 encodes ethylene-responsive element binding protein 2, which is critical for internode elongation. Microtubule-related genes Zmtub2, Zmtub3, Zmtub5, Zmtub6, and TUBG2 were commonly enriched among the three comparisons. Previous studies have shown that mutations in microtubule-associated genes cause the dwarf phenotype. However, nearly half of the common DEGs had no functional information, such as Zm00001d000107, Zm00001d000279, etc., implying their novel and specific functions in maize. Overall, this study identifies several potential plant height-related genes and contributes to linking genetic resources with maize breeding.
•A novel interpretation of scientific collaboration patterns is proposed from the perspective of symbiosis.•Quantitative metrics for the degree of symbiosis and the dynamics of scientific ...collaboration are taken into account to exploit the structure and evolution of collaboration patterns.•Empirical studies indicate that our symbiosis based framework can interpret very well the developmental and evolutionary trajectories of scientific collaboration.
Based on complementarity in terms of factors such as skill and knowledge, researchers might build long-term partnerships with one another during their scientific careers. It has been shown that such relationships have a significant positive impact on researchers’ scientific performance. However, the preferential connection mechanism in collaboration networks actually suggests the unequal positions of participants in the process of scientific collaboration. This study argues that this phenomenon is very similar to the symbiosis function in the natural world. Hence, this work provides a novel interpretation of scientific collaboration patterns from the perspective of symbiosis. In more detail, long-term collaboration relationships are investigated based on the scope of an academician dataset with multiple fields and an economic dataset. With the aid of a quantitative metric for symbiosis degree, six meta-patterns of the short-term evolution of symbiosis degree are proposed. Furthermore, by exploring the evolution of meta-patterns, four scientific collaboration patterns are summarized according to the common characteristics as follows: leading growth, continuous leadership, chasing each other, and standing on equal footing. Extensive experimental results on an academician dataset with multiple fields show that the collaboration network evolution of four collaboration patterns is consistent with our summarized characteristics based on symbiosis. This indicates that our symbiosis-based framework can be used to effectively interpret the developmental and evolutionary trajectories of scientific collaboration.
Super‐partnerships exist between scholars connected within densely‐knit collaboration networks. Understanding how such relationships affect scholars' careers is of great importance. In this paper, ...focusing on the longitudinal aspects of scientific collaboration, we analyze collaboration profiles from the egocentric perspective and use analytic extreme value thresholds to identify super‐partners. A total of 5722 pairs of super‐partners are found in the field of economics. The several interesting findings about super‐partners are summarized as follows. (1) The collaboration pattern of super‐partners can be divided into three types: the dual‐core, bridge, and triangle types. (2) Gender disparities are reflected in the collaboration among super‐partners, and the stability of super‐partnerships involving different combinations of genders displays different characteristics. The random‐effect model is constructed to explore the effect of a super‐partnership on both parties from the aspects of productivity and influence, which also shows gender disparities. (3) A super‐partnership contributes to above‐average productivity and citation impacts of the publication for three collaboration patterns, and the research improvement of the triangle type is the greatest among the three types. Overall, this paper explores the characteristics of super‐partners and the added value of a long‐term commitment, which provides quantitative insights into the effect on scientific collaboration associated with close collaboration.
Advanced and aggressive prostate cancer (PCa) depends on glutamine for survival and proliferation. We have previously shown that inhibition of glutaminase 1, which catalyzes the rate-limiting step of ...glutamine catabolism, achieves significant therapeutic effect; however, therapy resistance is inevitable. Here we report that while the glutamine carbon is critical to PCa survival, a parallel pathway of glutamine nitrogen catabolism that actively contributes to pyrimidine assembly is equally important for PCa cells. Importantly, we demonstrate a reciprocal feedback mechanism between glutamine carbon and nitrogen pathways which leads to therapy resistance when one of the two pathways is inhibited. Combination treatment to inhibit both pathways simultaneously yields better clinical outcome for advanced PCa patients.
Introduction of innovative biocatalytic processes offers great promise for applications in green chemistry. However, owing to limited catalytic performance, the enzymes harvested from nature's ...biodiversity often need to be improved for their desired functions by time-consuming iterative rounds of laboratory evolution. Here we describe the use of structure-based computational enzyme design to convert Bacillus sp. YM55-1 aspartase, an enzyme with a very narrow substrate scope, to a set of complementary hydroamination biocatalysts. The redesigned enzymes catalyze asymmetric addition of ammonia to substituted acrylates, affording enantiopure aliphatic, polar and aromatic β-amino acids that are valuable building blocks for the synthesis of pharmaceuticals and bioactive compounds. Without a requirement for further optimization by laboratory evolution, the redesigned enzymes exhibit substrate tolerance up to a concentration of 300 g/L, conversion up to 99%, β-regioselectivity >99% and product enantiomeric excess >99%. The results highlight the use of computational design to rapidly adapt an enzyme to industrially viable reactions.
Nanoscale metal organic frameworks (NMOFs) have become excellent drug carriers for the treatment of cancer or other diseases, due to the advantages of large surface area, high drug loading, tunable ...structure and easy functionalization, with potential application in the field of drug delivery. In this paper, UiO-66 NMOF was synthesized using terephthalic acid as organic ligand and zirconium chloride as metal salt, and then biocompatible chitosan (CS) and PEGylated chitosan (CS-g-mPEG)-decorated NMOFs as drug carriers were constructed by surface modification, using 5-FU as the drug model. The structures, size and morphology were characterized by IR, XRD, DLS, SEM and TEM respectively. The results showed that when the concentration was 0.0872 M, the molar ratio was 1:1 and the acetic acid amount was 2.9 mL, the average particle size of NMOFs was 145.60 nm and 171.73 nm, respectively. The drug loading capacity and encapsulation rate could reach 15.7% and 52.8%. The in vitro controlled drug release results indicated that the release rate accelerated with increasing temperature and decreasing initial amount, greatly reduced under acidic conditions, and the coating of CS and CS-g-mPEG on the surface of UiO-66 had the effect of controlling drug release, further improved the bioavailability of 5-FU. The decorated UiO-66 NMOFs show excellent biocompatibility as nanodrug carriers and can avoid rapid degradation under gastric acid, which are more suitable for oral drug delivery.
Fly ash-wasted glass based geopolymers were explored by hydrothermal hot pressing method. It could be used as high compressive strength materials, heat resistance materials, and solidification ...materials for fixing heavy metals.
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•Coal fly ash-waste glass based geopolymers were explored by HHP.•The geopolymers had high compressive strength and heat resistance abilities.•The geopolymers had good efficiency of encapsulating and fixing heavy metals.•It was a potential way for saving natural resources and protecting environment.
Hydrothermal hot pressing (HHP) was used to prepare high compressive strength fly ash-wasted glasses based geopolymers, which was subject to thermal analysis and the test of heat resistance as well as heavy metal solidification. Results showed that the geopolymers had good efficiency of encapsulating and fixing heavy metals. As for heavy metal element like Cu, Zn, Cd and Pb, the fixed efficiency reach at least 95%. Heat resistance test showed that the most mass-loss ratio of geopolymers was below 11.04% and the compressive strength was more than 55.27 MPa when it was calcined at 200–1000 °C for 2 h. During the calcining, geopolymers had gone through several main processes, including the evaporation of the free water, the bound water and constitutional water, the decomposition of carbonate, combustion of carbon, and crystallization reaction. XRD and FT-IR analysis showed that when calcined at 1000 °C, there produced several new crystallization phases with good heat resistance, including nepheline, kyanite, sillimanite. The improvement of this work does not only reflect that the hydrothermal hot pressing is featured by simple procedures, easy automation, timesaving and low cost, and also provide a long-term goal project, which could meet both demands: utilizing solid waste, saving resources and protecting the environment.
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