Spatio-Temporal Change of LakeWater Extent in Wuhan Urban Agglomeration Based on Landsat Images from 1987 to 2015

Urban lakes play an important role in urban development and environmental protection for the Wuhan urban agglomeration. Under the impacts of urbanization and climate change, understanding urban lake-water extent dynamics is significant. However, few studies on the lake-water extent changes for the Wuhan urban agglomeration exist. This research employed 1375 seasonally continuous Landsat TM/ETM+/OLI data scenes to evaluate the lake-water extent changes from 1987 to 2015. The random forest model was used to extract water bodies based on eleven feature variables, including six remote-sensing spectral bands and five spectral indices. An accuracy assessment yielded a mean classification accuracy of 93.11%, with a standard deviation of 2.26%. The calculated results revealed the following: (1) The average maximum lake-water area of the Wuhan urban agglomeration was 2262.17 km2 from 1987 to 2002, and it decreased to 2020.78 km2 from 2005 to 2015, with a loss of 241.39 km2 (10.67%). (2) The lake-water areas of loss of Wuhan, Huanggang, Xianning, and Xiaogan cities, were 114.83 km2, 44.40 km2, 45.39 km2, and 31.18 km2, respectively, with percentages of loss of 14.30%, 11.83%, 13.16%, and 23.05%, respectively. (3) The lake-water areas in the Wuhan urban agglomeration were 226.29 km2, 322.71 km2, 460.35 km2, 400.79 km2, 535.51 km2, and 635.42 km2 under water inundation frequencies of 5%–10%, 10%–20%, 20%–40%, 40%–60%, 60%–80%, and 80%–100%, respectively. The Wuhan urban agglomeration was approved as the pilot area for national comprehensive reform, for promoting resource-saving and environmentally friendly developments. This study could be used as guidance for lake protection and water resource management

Performance assessment for the integrated green-gray-blue infrastructure under extreme rainfall scenarios

Synergistic allocation of urban stormwater infrastructure is critical to flood risk prevention and control under extreme rainfall events. This study focuses on the interaction regularity of green, gray, and blue infrastructure in the process of runoff retention and discharge under extreme rainfall scenarios. Three strategies, namely, gray infrastructure, green-gray infrastructure, and green-gray-blue infrastructure, are proposed to analyze the effectiveness of different scenarios on flood risk control capabilities of urban drainage systems and to determine the key influencing factors of the three strategies. The results show that green-gray-blue infrastructure demonstrates synergy in improving the efficiency of urban drainage systems. Under gravity drainage conditions, the backwater jacking caused by high river water levels has a certain impact on the smooth discharge of stormwater runoff in urban drainage systems. This case study identified a sensitive range in the influence of water level on runoff control and drainage function and an adaptive range in which the flood increases slightly with the water level increase. These present notable rules in improving the synergistic effect of blue infrastructure in the integrated urban green-gray-blue infrastructure system

Bleomycin Loaded Magnetite Nanoparticles Functionalized by Polyacrylic Acid as a New Antitumoral Drug Delivery System

Objective. To prepare, characterize, and analyze the release behavior of bleomycin-loaded magnetite nanoparticles (BLM-MNPs) coated with polyacrylic acid (PAA) as a new drug delivery system that can be specifically distributed in the tumor site. Methods. BLM-MNPs coated with PAA were prepared using a solvothermal approach. The particles were characterized using scanning electron microscope (SEM), vibrating sample magnetometer (VSM), and Fourier transform infrared spectroscopy (FTIR). The loading and release behaviors of BLM-MNPs were examined by a mathematical formula and in vitro release profile at pH 7.5. Results. The sphere Fe 3 O 4 nanoparticles with the size of approximately 30 nm exhibit a saturation magnetization of 87 emu/g. The noncoordinated carboxylate groups of PAA confer on the good dispersibility in the aqueous solution and lead to a good loading efficiency of BLM reaching 50% or higher. Approximately 98% of immobilized BLM could be released within 24 h, of which 22.4% was released in the first hour and then the remaining was released slowly and quantitatively in the next 23 hours. Conclusion. BLMMNPs were prepared and characterized successfully. The particles show high saturation magnetization, high drug loading capacity, and favorable release property, which could contribute to the specific delivery and controllable release of BLM, and the BLM-MNPs could be a potential candidate for the development of treating solid tumors

How Gamification Affordances Drive Micro Public Welfare

Nowadays, micro public welfare has become a popular way for citizens to help disadvantaged people and protect our environment. And Internet enterprises have developed gamified MiniApps on their online platforms in order to attract users to perform micro public welfare behaviors. In such gamified MiniApps, users’ perceived gamification affordances the gamified elements offer will satisfy their psychological goals and motivate their micro public welfare behaviors. Based on goal-framing theory, we explore how gamification affordances help users achieve their psychological goals and explain how users’ psychological goals drive them take part in micro public welfare. To test our research questions, we collected 205 questionnaires and used SmartPLS to test the structural equation model we built. Finally, we find out autonomy support and visibility of achievement can realize users’ psychological goals including hedonic goal, gain goal and normative goal respectively, while competition and interaction satisfy their gain goal positively

Spatio-Temporal Change of LakeWater Extent in Wuhan Urban Agglomeration Based on Landsat Images from 1987 to 2015

Urban lakes play an important role in urban development and environmental protection for the Wuhan urban agglomeration. Under the impacts of urbanization and climate change, understanding urban lake-water extent dynamics is significant. However, few studies on the lake-water extent changes for the Wuhan urban agglomeration exist. This research employed 1375 seasonally continuous Landsat TM/ETM+/OLI data scenes to evaluate the lake-water extent changes from 1987 to 2015. The random forest model was used to extract water bodies based on eleven feature variables, including six remote-sensing spectral bands and five spectral indices. An accuracy assessment yielded a mean classification accuracy of 93.11%, with a standard deviation of 2.26%. The calculated results revealed the following: (1) The average maximum lake-water area of the Wuhan urban agglomeration was 2262.17 km2 from 1987 to 2002, and it decreased to 2020.78 km2 from 2005 to 2015, with a loss of 241.39 km2 (10.67%). (2) The lake-water areas of loss of Wuhan, Huanggang, Xianning, and Xiaogan cities, were 114.83 km2, 44.40 km2, 45.39 km2, and 31.18 km2, respectively, with percentages of loss of 14.30%, 11.83%, 13.16%, and 23.05%, respectively. (3) The lake-water areas in the Wuhan urban agglomeration were 226.29 km2, 322.71 km2, 460.35 km2, 400.79 km2, 535.51 km2, and 635.42 km2 under water inundation frequencies of 5%–10%, 10%–20%, 20%–40%, 40%–60%, 60%–80%, and 80%–100%, respectively. The Wuhan urban agglomeration was approved as the pilot area for national comprehensive reform, for promoting resource-saving and environmentally friendly developments. This study could be used as guidance for lake protection and water resource management

Zn-based batteries for energy storage

Zn-based electrochemistry is considered to be the most promising alternative to Li-ion batteries due to its abundant reserves and cost-effectiveness. In addition, aqueous electrolytes are more convenient to be used in Zn-based batteries due to their good compatibility with Zn-chemistry, thereby reducing cost and improving safety. Furthermore, Zn2+/Zn couples involve two-electron redox chemistry, which can provide higher theoretical energy capacity and energy density. Based on this, a series of Zn-based battery systems, including Zn-ion batteries, Zn-air batteries, and Zn-based redox flow batteries, have received more and more research attention. Here, the fundamentals and recent advances in Zn-based rechargeable batteries are presented, along with perspectives on further research directions

An analysis of typical and atypical MRI findings of brain lesions in multiple sclerosis: a 82 cases report

Objective To analyse the typical and atypical magnetic resonance imaging (MRI) findings of brain multiple sclerosis (MS) lesions in Chinese MS patients. Methods MRI findings of 82 Chinese MS patients who fulfilled McDonald criteria were reviewed retrospectively. The analysis items included the distribution, size, number, shape, intensity and enhancement of all lesions on head MRI. Results The typical MRI findings of these patients were as follow: 1) most lesions were located at periventricle area (62 cases, 75.61%) and the deep part of supratentorial white matter (55 cases, 67.07%); 2) there were over 10 lesions in 62 cases (75.61%); 3) the lesions were predominantly ≤ 1 cm (62 cases, 75.61%), and the next were > 5 cm (23 cases, 28.05%); 4) intensity and enhancement features presented T1WI iso ⁃ or hypo ⁃ intensity, T2WI hyperintensity, and proton density weighted image (PDWI) lesions intensity higher than water in the ventricle; the black hole appeared in various size and mostly with round or patchy shape; nodular enhancement was more often seen in lesions smaller than 1 cm and ring⁃like in middle size lesions; peripheral or irregular enhancement was popular for big lesions and arc ⁃ like for subcortical lesions. In the atypical MRI findings: 1) lesions were large [maximum diameter > 5 cm (23 cases, 28.05%)]; 2) lesion enhancement was remarkable and last longer; 3) brain stem lesions were more common (61 cases, 74.39%). Conclusion Multiple and small lesions at periventricle area or deep white matter are the typical MRI findings for MS. Deformation due to MS lesions, micro⁃ black hole at convex or line⁃shape black hole at periventricle, arc ⁃ like enhancement for juxtacortical lesions or enhancement beside the temporal horn are improtant in the diagnosis of MS. Big lesions with remarkable enhancement and prevalent in brain stem are the findings in Chinese MS patients which are different from American or European MS cases. DOI：10.3969/j.issn.1672-6731.2011.03.01

The Application of Bacillus subtilis for Adhesion Inhibition of Pseudomonas and Preservation of Fresh Fish

Inhibiting the growth of spoilage bacteria, such as Pseudomonas spp., is key to reducing spoilage in fish. The mucus adhesion test in vitro showed that the adhesion ability of Bacillus subtilis was positively correlated with its inhibition ability to Pseudomonas spp. In vivo experiments of tilapia showed that dietary supplementation with B. subtilis could reduce the adhesion and colonization of Pseudomonas spp. in fish intestines and flesh, as well as reduce total volatile basic nitrogen (TVB-N) production. High throughput and metabolomic analysis showed treatment with B. subtilis, especially C6, reduced the growth of Pseudomonas spp., Aeromonas spp., Fusobacterium spp., and Enterobacterium spp., as well as aromatic spoilage compounds associated with these bacteria, such as indole, 2,4-bis(1,1-dimethylethyl)-phenol, 3-methyl-1-butanol, phenol, and 1-octen-3-ol. Our work showed that B. subtilis could improve the flavor of fish by changing the intestinal flora of fish, and it shows great promise as a microecological preservative

Bleomycin Loaded Magnetite Nanoparticles Functionalized by Polyacrylic Acid as a New Antitumoral Drug Delivery System

Objective. To prepare, characterize, and analyze the release behavior of bleomycin-loaded magnetite nanoparticles (BLM-MNPs) coated with polyacrylic acid (PAA) as a new drug delivery system that can be specifically distributed in the tumor site. Methods. BLM-MNPs coated with PAA were prepared using a solvothermal approach. The particles were characterized using scanning electron microscope (SEM), vibrating sample magnetometer (VSM), and Fourier transform infrared spectroscopy (FTIR). The loading and release behaviors of BLM-MNPs were examined by a mathematical formula and in vitro release profile at pH 7.5. Results. The sphere Fe3O4 nanoparticles with the size of approximately 30 nm exhibit a saturation magnetization of 87 emu/g. The noncoordinated carboxylate groups of PAA confer on the good dispersibility in the aqueous solution and lead to a good loading efficiency of BLM reaching 50% or higher. Approximately 98% of immobilized BLM could be released within 24 h, of which 22.4% was released in the first hour and then the remaining was released slowly and quantitatively in the next 23 hours. Conclusion. BLM-MNPs were prepared and characterized successfully. The particles show high saturation magnetization, high drug loading capacity, and favorable release property, which could contribute to the specific delivery and controllable release of BLM, and the BLM-MNPs could be a potential candidate for the development of treating solid tumors

Development and application of lightning flashover limited equipment for 220 kV AC transmission line

In order to solve the operation problems of traditional lightning protection equipment (for example, line arrester and parallel gap) for 220 kV AC transmission line, a novel lightning protection equipment – lightning flashover limited equipment for 220 kV AC transmission line – has been developed successfully, which owns the advantages of line arrester and parallel gap. Technical parameters, and electrical and mechanical performances are researched through theoretical calculation and experimental verification, and an installation structure of new split type is designed. The results show that the lightning flashover limited equipment has good electrical and mechanical performance and meets insulation, tensile, and bending requirements. By now, more than 200 sets of lightning flashover limited equipment for 220 kV AC transmission line have been applied on lines in four provinces of China. About 2 years of operating experience show that all the sets of lightning flashover limited equipment work safely and reliably