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The disc-seal single screw pump (DSSP) used in the field of high viscosity oily sludge transport has a huge advantage. However, there is no research on the pressurization characteristics of the DSSP at present, which makes its application limited. In view of this, the pressurization process mathematical model of the DSSP was established based on the geometric model of the pump. By using this model, the pressurization characteristics of DSSP and the influence of working parameters on the pressurization process were studied combined with the principle of back-flow pressurization. Analysis results show that the instantaneous pressurization process could be realized mainly depending on the reflux pressurization from the outlet chamber to the pressurization chamber when the screw rotor rotating angle is located at -5° to +5°. The pressure in the pressurization chamber will increase with the increase of working parameters which include inlet pressure, outlet pressure, screw rotation velocity and dynamic viscosity of fluid medium in the area of flow-back pressurization. The screw rotation velocity and the viscosity of the conveying medium have significant effects on the peak pressure in the pressurization chamber, and the peak pressure in the pressurization chamber is proportional to the screw rotation velocity and the dynamic viscosity coefficient of the conveying medium. The proportional coefficient between the peak pressure and the screw rotation velocity is 6.29×104. The proportional coefficient between the peak pressure and the dynamic viscosity of the conveying medium is 6.28×106.

In some cases Metformin (MF) produces intestinal discomfort and increased risk of dysbiosis. We developed a novel astragalus compound oral solution (termed "OS") and investigated effects of treatments with OS alone or in combination with metformin (MF) in a type 2 diabetes (T2D) mouse model. OS can treat T2D in mice. OS, in comparison with MF (OS + MF), was more effective in improving HDL, ALT, hepatic glycogen, and GSH-px levels, and in protecting several organs simultaneously. Gut microbiota composition and diversity were significantly better for OS and OS + MF than for MF. Helicobacter, Oscillospira, Mucispirillum, Dehalobacterium, Anaerotruncus, Subdoligranulum, Akkermansia, Allobaculum, and Ochrobactrum were significantly correlated with FBG, liver function indicators, and islet cell areas. Our findings suggest that OS applied in combination with MF promoted health in the T2D mouse model through effects on 192 related targets to regulate glucose and lipid metabolism, protect organs, and improve gut microbiota composition

Compared to traditional air freezing, immersion chilling and freezing shows an improvement in the freezing effect on meat quality, but it is not known whether this advantage persists over longer storage periods. Therefore, the objective of the current study was to compare the effects of immersion chilling and freezing (ICF) and traditional air freezing (TAF) on the physical and chemical indexes in beef longissimus muscle during a storage period of 150 days. In the current study, the longissimus muscle from Luxi cattle (aged 20–24 months) was analyzed, with samples independently frozen by ICF and TAF. After the core temperature was frozen to below −18 degrees by the two chilling methods, samples were transferred to a −18 degrees cold room for further storage. During the storage period, physical and chemical indexes, mainly including color and texture qualities, total volatile base nitrogen (TVB‐N) and peroxide value (POV) were measured and comparatively analyzed at several fixed time points. A higher freezing rate was observed in ICF (5.124 cm/h) than in TAF (0.194 cm/h), and better microstructure was observed in ICF treatment. Besides, peak force values and total energy values were significantly lower in the TAF group than in the ICF group during the first 45 days of freezing storage time (p, Freezing is one of the most effective ways to preserve the quality of beef and is used to minimize the product loss. Many studies have demonstrated that the immersion chilling and freezing shows good improvement on the freezing effect of meat quality; however, it is not known whether this advantage will still exist in a longer storage period. The aim of current study was to explore the effects of different freezing methods, including the immersion chilling and freezing (ICF) and traditional air freezing (TAF), on the physical and chemical indexes in beef longissimus muscle during a period of 150‐day storage.

Background Crime researchers often use publicly available geocoding services to obtain crime locations and conduct subsequent analysis. The quality of these geocoding platforms has not been extensively investigated, especially in the crime research field. The match rate is often employed for this purpose, but this measures only absolute performance at a specified scale and cannot reflect the performance of a platform at different accuracy levels. By expanding match rate to multiple scales, we compared the quality of publicly available geocoding services in China. Methods In this study, we develop a set of evaluation metrics by clarifying the definition of the match rate and considering the multiscale characteristics of geocoding errors. To interpret the geocoding errors of addresses, the positional errors are classified into more detailed types in accordance with their topological relationships with mapping units. Using burglary addresses recorded in N city, the quality of the geocoding services provided by four mainstream online geocoding services in China are compared based on these metrics. Results The match rates of the four geocoding platforms are high enough to maintain the burglary distribution patterns at the subdistrict and district levels but cannot satisfy this need at the building level. Three of the four platforms can geocode enough addresses for spatial analysis at the community level, while Tencent cannot. For commercial addresses, the match rates of the four platforms for residential addresses cannot satisfy the needs of burglary mapping at the building level but can satisfy these needs at any other level. For residential addresses, Tencent is the only platform that cannot provide satisfactory results for community-level mapping. For gated community-level mapping, Baidu and Tianditu can provide marginally satisfactory results. Based on the accuracy levels provided by each platform, the applicability of the results at each level are further analyzed. Conclusions Although this study is limited by address type and data volume, the results suggest users to select appropriate geocoding service based on mapping unit sizes and address types. The results can also help users determine whether the geocoding result at certain accuracy level meet their needs. This research also provides guidance for address-based users beyond crime analysis.

The Qinghai-Tibetan Plateau, with low precipitation, low oxygen partial pressure, and temperatures routinely dropping below −30 °C in winter, presents several physiological challenges to its fauna. Yet it is home to many endemic mammalian species, including the plateau pika (Ochotona curzoniae). How these small animals that are incapable of hibernation survive the winter is an enigma. Measurements of daily energy expenditure (DEE) using the doubly labeled water method show that pikas suppress their DEE during winter. At the same body weight, pikas in winter expend 29.7% less than in summer, despite ambient temperatures being approximately 25 °C lower. Combined with resting metabolic rates (RMRs), this gives them an exceptionally low metabolic scope in winter (DEE/RMRt = 1.60 ± 0.30; RMRt is resting metabolic rate at thermoneutrality). Using implanted body temperature loggers and filming in the wild, we show that this is achieved by reducing body temperature and physical activity. Thyroid hormone (T(3) and T(4)) measurements indicate this metabolic suppression is probably mediated via the thyroid axis. Winter activity was lower at sites where domestic yak (Bos grunniens) densities were higher. Pikas supplement their food intake at these sites by eating yak feces, demonstrated by direct observation, identification of yak DNA in pika stomach contents, and greater convergence in the yak/pika microbiotas in winter. This interspecific coprophagy allows pikas to thrive where yak are abundant and partially explains why pika densities are higher where domestic yak, their supposed direct competitors for food, are more abundant.

Background: Dendrobium officinale Kimura et Migo is a traditional functional food and medicinal plant in China. Due to low natural regeneration rates, habitat destruction, excessive collection and commercial trade, D. officinale is severely threatened, and commercial artificial-sheltered cultivation has been massively used to meet the needs of the market. Aim: To comprehensively compare the accumulation of nutritional compounds during 3-5 years of introduced, artificial-sheltered cultivation from southern to northern China.Methods: D. officinale of the same species were artificially cultivated in the southern traditional cultivation area, Anhui and the new northern cultivation area, Beijing. First, samples were collected in the third, fourth, and fifth years of growth, and nutritional quality indexes, including polysaccharides, alkaloids, flavonoids and total phenolic content, were determined. Second, an untargeted metabolomics method was used to investigate metabolic variations in D. officinale stems between Anhui and Beijing cultures in the fifth year.Results: After comparing the nutrient accumulation in different growing years, the idea harvest time was found in the third growing year in both cultivation areas. Of them, the contents of polysaccharides, flavonoids and total polyphenol were higher in cultivation in Anhui than Beijing, but the accumulation of alkaloid content was much lower in Anhui. The highest amount of polysaccharides of Dendrobium officinale was found in the three-year cultivation in Anhui, which reached 515.75 mg/g. When metabolites were analysed, a total of 272 metabolites were detected in the current study, including 27 up-regulated and 73 down-regulated metabolites in D. officinale cultivated in Beijing compared with samples from Anhui. Conclusion: D. officinale artificially and transplanted cultivated from southern to northern China showed some significant differences in the accumulation of nutrient compounds. Planting in northern China has some specific advantages, but the overall nutritional value is not as good as planting in southern China. Our study contributes to a better understanding of the nutrient profiles of D. officinale through artificial cultivation in different areas.

Molecular dynamics simulations of droplets in gas forced vortexes by applying a virtual rotational potential were presented. The result showed that the flow field scale of the simulation performed can reflect the macroscopic characteristics. The trajectories of water droplets are longer than that of oil droplets within a certain radius of flow field. A droplet trajectory model was proposed to predict droplet behavior. The study continued to investigate droplet collisions. It was observed that the large oil droplet and the downwind small water droplets produced near head-on, highly off-centre and scraping-adhering collisions, forming stable two-phase interfaces. The slight changes of the interfaces between water and oil droplets under the action of rotating flow field can be reflected by van der Waals interaction. The intermolecular hydrogen bonds form when two water droplets collide. Our study provides a new idea for further understanding of droplet collision in gas flow field.

As a measurement of the residential population, the Census population ignores the mobility of the people. This weakness may be alleviated by the use of ambient population, derived from social media data such as tweets. This research aims to examine the degree in which geotagged tweets, in contrast to the Census population, can explain crime. In addition, the mobility of Twitter users suggests that tweets as the ambient population may have a spillover effect on the neighboring areas. Based on a yearlong geotagged tweets dataset, negative binomial regression models are used to test the impact of tweets derived ambient population, as well as its possible spillover effect on theft crimes. Results show: (1) Tweets count is a viable replacement of the Census population for spatial theft pattern analysis, (2) tweets count as a measure of the ambient population shows a significant spillover effect on thefts, while such spillover effect does not exist for the Census population, (3) the combination of tweets and its spatial lag outperforms the Census population in theft crime analyses. Therefore, the spillover effect of the tweets derived ambient population should be considered in future crime analyses. This finding may be applicable to other social media data as well.

The increasing ecological awareness and stringent requirements for environmental protection have led to the development of water lubricated journal bearings. For the investigation of water-lubricated journal bearings, a new structured mesh movement algorithm for the CFD model is developed and based on this method, the nonlinear transient hydrodynamic force model is established. Then, with consideration of velocity perturbation, a method to determine dynamic coefficients and linear hydrodynamic forces is promoted. After validation of static equilibrium position and stiffness coefficients, a comparative linear and nonlinear hydrodynamic force analysis of multiple grooves water-lubricated journal bearings (MGWJBs) is conducted. The calculation results indicate that the structured mesh movement algorithm is suitable for the dynamic characteristics investigation of water-lubricated journal bearings. And the comparative study shows that there is a considerable difference between the linear and nonlinear hydrodynamic forces of MGWJBs. Further investigation should be carried to evaluate the dynamic responses of rotor supported by MGWJBs under difference force models.

A hot spot refers to numerous crime incidents clustered in a limited space-time range. The near-repeat phenomenon suggests that every victimization might form a contagion-like pattern nearby in terms of both space and time. In this article, the near-repeat phenomenon is used to analyze the risk levels around hot spots. Utilizing a recent burglary dataset in N (a large city located in southeastern China), we examine the near-repeat phenomenon, the results of which we then use to test the contributions of hot spots. More importantly, we propose a temporal expanded near-repeat matrix to quantify the undulation of risk both before and after hot spots. The experimental results demonstrate that hot spots always form. Space-time areas of high risk are always variable in space and time. Regions in the vicinity of hot spots simultaneously share this higher risk. In general, crime risks around hot spots present as a wave diffusion process. The conclusions herein provide a detailed analysis of criminal patterns, which not only advances previous results but also provides valuable research results for crime prediction and prevention.

The purpose of this descriptive review was to delineate the current knowledge of bronchiectasis in terms of prevalence, burden of disease, pathophysiology, and management.The National Library of Medicines MEDLINE and PubMed database (2005-2013) were used to conduct a search using the keyword term "bronchiectasis". The references for articles being considered for inclusion were searched from additional sources such as conference proceedings.Criteria for inclusion of articles included data outlining epidemiology, pathogenesis, diagnosis, and evidence-based guidelines for management of bronchiectasis. In assessing the quality of the articles, factors such as size of the population studied, clinical setting of the study, and whether or not the studies were prospective or retrospective were taken into consideration. Review articles were also included in our data collection. RESULTS Despite many advances in modern medicine, bronchiectasis still remains a significant public health problem in developed countries and the developing world. It carries a significant burden worldwide in terms of morbidity and mortality, as well as financially to the affected population. In addition, bronchiectasis may associate with chronic airflow obstruction, regardless of smoking status.Bronchiectasis is a debilitating illness responsible for significant morbidity with a poor health-related quality of life. The condition has a substantial socioeconomic cost because both primary and secondary healthcare resources are frequently used and periods of sick leave are common.

Angiogenesis is a critical step for the growth and metastasis of solid tumors, and it is a major therapeutic target for the development of anti-angiogenics for cancer treatment. Thalidomide is reported to be an anti-angiogenic agent, which is currently in phase II clinical trials for the treatment of advanced malignancies. However, the mechanism of thalidomide in angiogenesis is not completely understood. This study was undertaken to investigate the effect of thalidomide on the expression of angiogenesis growth factors in human lung cancer cells. In this report, we show that thalidomide downregulated the mRNA and protein expression of basic fibroblast growth factor (bFGF) in the human lung adenocarcinoma cell line A549, and that the effect of thalidomide was time and concentration-dependent. In contrast, the expression of vascular endothelial growth factor (VEGF) by thalidomide in these cells was in two phases. The mRNA and protein expression of VEGF was increased in the lung cancer cells treated with 0.6-6 microg/ml thalidomide, while higher concentrations of thalidomide decreased VEGF levels significantly in these cells. These data suggest that the anti-angiogenic or antitumor activity of thalidomide may be partly mediated through the regulation of the levels of angiogenesis growth factors.