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In order to solve the two structural problems of trapped oil and large flow ripple in gear pump and based on transmission advantages of cycloid gear and its forming principle，tooth number and radius factor of rolling circle which can best reflect pump performance are taken as structural parameters of cycloidal tooth profile，central angle，radius factor and pressure angle of addendum arc functional parameters of gear pump，a cycloid tooth profile with a contact ratio of 1 is constructed in a reverse way and the structural problem of large flow ripple of original single gear pair is solved by the construction of double gear pairs and minimization of ripple coefficient. All results show that the reverse design method of cycloidal tooth profile is simple and accurate，and can be directly used by general engineers； the contact ratio of a single gear pair is 1 to ensure that gear pump has no trapped oil phenomenon； the axial dislocation assembly of double gear pairs with special angle of π divided by tooth number is easy to be realized，and axial comprehensive contact ratio is 2 to ensure transmission stability of cycloidal gear pair； minimum number of teeth is 6 and there is no root cutting phenomenon； compared with single gear pair，an about 75% ripple improvement rate is seen in double gear pair and the optimal tooth profile parameters based on the minimization of ripple factor can be directly applied to the production practice，etc. The aim is to provide a theoretical basis for further research and development of low flow ripple gear pump without trapped oil.

Abstract Background Glycolate is an important α-hydroxy carboxylic acid widely used in industrial and consumer applications. The production of glycolate from glucose in Escherichia coli is generally carried out by glycolysis and glyoxylate shunt pathways, followed by reduction to glycolate. Glycolate accumulation was significantly affected by nitrogen sources and isocitrate dehydrogenase (ICDH), which influenced carbon flux distribution between the tricarboxylic acid (TCA) cycle and the glyoxylate shunt, however, the mechanism was unclear. Results Herein, we used RNA-Seq to explore the effects of nitrogen sources and ICDH knockout on glycolate production. The Mgly534 strain and the Mgly624 strain (with the ICDH deletion in Mgly534), displaying different phenotypes on organic nitrogen sources, were also adopted for the exploration. Though the growth of Mgly534 was improved on organic nitrogen sources, glycolate production decreased and acetate accumulated, while Mgly624 achieved a balance between cell growth and glycolate production, reaching 0.81 g glycolate/OD (2.6-fold higher than Mgly534). To further study Mgly624, the significant changed genes related to N-regulation, oxidative stress response and iron transport were analyzed. Glutamate and serine were found to increase the biomass and productivity respectively. Meanwhile, overexpressing the arginine transport gene argT accelerated the cell growth rate and increased the biomass. Further, the presence of Fe2+ also speeded up the cells growth and compensated for the lack of reducing equivalents. Conclusion Our studies identified that ICDH knockout strain was more suitable for glycolate production. RNA-Seq provided a better understanding of the ICDH knockout on cellular physiology and glycolate production.

Wolf Pack Algorithm (WPA) is a swarm intelligence algorithm that simulates the food searching process of wolves. It is widely used in various engineering optimization problems due to its global convergence and computational robustness. However, the algorithm has some weaknesses such as low convergence speed and easily falling into local optimum. To tackle the problems, we introduce an improved approach called OGL-WPA in this work, based on the employments of Opposition-based learning and Genetic algorithm with Levy's flight. Specifically, in OGL-WPA, the population of wolves is initialized by opposition-based learning to maintain the diversity of the initial population during global search. Meanwhile, the leader wolf is selected by genetic algorithm to avoid falling into local optimum and the round-up behavior is optimized by Levy's flight to coordinate the global exploration and local development capabilities. We present the detailed design of our algorithm and compare it with some other nature-inspired metaheuristic algorithms using various classical test functions. The experimental results show that the proposed algorithm has better global and local search capability, especially in the presence of multi-peak and high-dimensional functions.

Fair skins are traditionally viewed as beautiful in Eastern regions of the world, and whitening effect is therefore eternally pursued. The aim of this study was to evaluate the whitening effectiveness of a traditional Chinese medicine (TCM) formula using laser Doppler technology. In addition, a melanin and erythema meter (Mexameter MX18/MPA-9, Courage&Kahazaka) and VISIA facial imaging booth (VISIA-CR, Canfield) were used to establish parallel comparisons. Pre- and post-treatment results showed that the TCM formula exhibits the best skin whitening effect. This was followed in effectiveness by the vitamin C group. The negative control and blank groups showed no whitening effect. The obtained results indicated that skin micro-circulation was enhanced in the TCM formula group. Therefore,this method could provide sufficient nutritive substances to fibroblasts and collagen, which in turn remove cell metabolic waste and other harmful substances such as superoxide anion in a timely manner. This improves the overall health of skin cells.

Abstract Geographical, environmental and pollution conditions affect facial skin health, but their effects on skin appearance have not been elucidated. This study aimed to describe the skin barrier and skin tone characteristics of Chinese subjects according to lifestyle and environmental conditions using in vitro measurements. In total, 1092 women aged 22–42 years were recruited from 7 representative Chinese cities. Eight skin parameters (hydration, sebum, pH, transdermal water loss, individual type angle, melanin index, erythema index, yellowness) were measured using noninvasive instruments; individual lifestyle data were also collected. Data on four meteorological factors (air temperature, relative humidity, sunshine duration, wind speed) and seven air pollution indicators (air quality index, fine particulate matter, breathable particulate matter, sulfur dioxide, nitrogen dioxide, carbon monoxide and ozone) were collected in each city from the China Meteorological Administration. Facial skin characteristics differed significantly between cities. Facial skin barrier characteristics and skin tones showed regional differences, with a better skin barrier associated with the western region, as indicated by high skin hydration and sebum secretion and a low pH value. According to the value of transdermal water loss, lighter and darker skin tones were found in the western and southern regions, respectively. Environmental conditions affected facial skin status. Air pollution induced facial skin issues, with fine particulate matter and nitrogen dioxide contributing the most. Individual lifestyles affected the facial skin barrier and skin tone.

Advanced glycation end products (AGEs) are a series of stable compounds produced under non-enzymatic conditions by the amino groups of biomacromolecules and the free carbonyl groups of glucose or other reducing sugars commonly produced by thermally processed foods. AGEs can cause various diseases, such as diabetes, atherosclerosis, neurodegeneration, and chronic kidney disease, by triggering the receptors of AGE (RAGEs) in the human body. There is evidence that AGEs can also affect the different structures and physiological functions of the skin. However, the mechanism is complicated and cumbersome and causes various harms to the skin. This article aims to identify and summarise the formation and characteristics of AGEs, focussing on the molecular mechanisms by which AGEs affect the composition and structure of normal skin substances at different skin layers and induce skin issues. We also discuss prevention and inhibition pathways, provide a systematic and comprehensive method for measuring the content of AGEs in human skin, and summarise and analyse their advantages and disadvantages. This work can help researchers acquire a deeper understanding of the relationship between AGEs and the skin and provides a basis for the development of effective ingredients that inhibit glycation.

Abstract In recent years, studies of traditional medicinal plants have gradually increased worldwide because the natural sources and variety of such plants allow them to complement modern pharmacological approaches. As computer technology has developed, in silico approaches such as virtual screening and network analysis have been widely utilized in efforts to elucidate the pharmacological basis of the functions of traditional medicinal plants. In the process of new drug discovery, the application of virtual screening and network pharmacology can enrich active compounds among the candidates and adequately indicate the mechanism of action of medicinal plants, reducing the cost and increasing the efficiency of the whole procedure. In this review, we first provide a detailed research routine for examining traditional medicinal plants by in silico techniques and elaborate on their theoretical principles. We also survey common databases, software programs and website tools that can be used for virtual screening and pharmacological network construction. Furthermore, we conclude with a simple example that illustrates the whole methodology, and we present perspectives on the development and application of this in silico methodology to reveal the pharmacological basis of the effects of traditional medicinal plants.

Flotation machines and flotation columns are widely used as separation equipment for coal sludge. In order to obtain better flotation results for different particle sizes, the bubble distribution and size in the flow field need to be studied. In this paper, a novel three-phase fluidized bed flotation column (TFC) was designed, and the shear effect of liquid velocity (0.198 m/s, 0.226 m/s, and 0.254 m/s) and static bed height (0.1 m, 0.2 m, and 0.3 m) on the bubbles in the mineralized flow field region was investigated and evaluated for the formation of bubbles by shear in laboratory and semi-industrial experiments. The results show that the increase in filling bed height has a very obvious strengthening effect on the reduction of bubble diameter, and after the filling bed height reaches a certain value, the filling bed height will weaken the effect of apparent gas velocity on bubble diameter. The apparent gas velocity has different influencing effects on bubble diameter, and under conditions of low water velocity, the increase in the apparent gas velocity contributes to the reduction of bubble diameter. The conclusions of this study are expected to optimize the operating parameters of the flotation mineralization process and enrich the study of TFC, which can provide a reference for the design of future TFC studies. [ABSTRACT FROM AUTHOR]

Against the backdrop of cyclical fluctuations in the global economy, significant attention has been devoted to the resilience of urban economic systems in response to external shocks. Current academic understanding of the characteristics and primary types of urban economic resilience remains limited, with research in this area still at a preliminary stage. An in-depth analysis of the characteristics and patterns of economic resilience within urban systems could not only improve the understanding of urban economic resilience but also provide differentiated case studies for cities aiming to withstand future global financial crises. Based on this premise, Complex Adaptive Systems (CAS) theory is employed to analyze the potential factors influencing urban economic resilience. This study uses 54 county-level units in Jiangsu Province as empirical subjects, examining their economic resilience characteristics in response to the 2008 financial crisis across two dimensions: resistance and resilience. The study further analyzes five highly explanatory influencing factors to perform a grouping analysis of economic resilience among Jiangsu counties. The findings reveal that: 1) during the financial crisis, the level of impact across Jiangsu's county areas displayed a spatial pattern of "high in the south and low in the north;" 2) the agglomeration of enterprise entities and industrial diversity during the recovery period had a positive effect on county-level economic resilience; 3) the impact of foreign trade intensity on economic resilience varied across cities and stages, reflecting a dual role; 4) there exist two and five pathways to achieve high economic resilience during resistance and recovery periods, respectively, with close spatial proximity, industrial diversification, core industry agglomeration, and balanced trade flows emerging as critical elements for enhancing economic resilience. This study identifies a potential adaptive path for urban economic resilience: to counteract recessionary forces and stabilize fundamentals by developing sectors less impacted by shocks during the resistance period. During the recovery phase, diversifying industrial sectors can foster new industry strengths, reposition the urban economy, and enable dynamic structural adjustments to promote recovery and create new economic development.