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The pore structure of coal affects spontaneous combustion to a certain extent. The pore structure of the coal body will be altered after prolonged waterlogging and is highly susceptible to spontaneous combustion in the presence of elevated ground temperatures. To study the pore structure changes in the coal body after immersion and drying. The coal samples from the Jinjitan coal mine in Yulin, Shaanxi Province, the Tangkou coal mine in Jining, Shandong Province, and the Gaojiapu coal mine in Shaanxi Province were scanned by electron microscopy and low-temperature nitrogen adsorption experiments. This study indicates that after water immersion, the fracture pores of the coal body are developed, the morphology changes, and the percentage of pore fracture area increases significantly. With the increase in immersion time, the pore types of Coal samples A and C did not change, being delicate necked bottle-shaped pores and open, permeable pores, respectively. Coal sample B pore type developed from impermeable pores to open pores. The cumulative pore volume of coals from all three areas increased for the same pore size. The contribution of micropores to the BET specific surface area and total BJH pore volume was more significant than the original coal samples. The specific surface area of A90, B30, and C60 was larger than that of the other coal samples for the soaking time, so it can be assumed that A90, B30, and C60 have a higher propensity for spontaneous combustion. Underwater immersion, the pore type of coal samples from coal mines in Northwest China did not change, but the pore types of coal samples from coal mines in East China changed. Therefore, the pore structure of gas coal was easily changed underwater dissolution. [ABSTRACT FROM AUTHOR]

Seaweed aquaculture is vital in protecting the marine eco-environment and mitigating climate change. China generates more than half of the world's total seaweed production. However, despite multiple local studies, accurate and reliable information on broad-scale seaweed farms is still scarce. Using an object-based method to classify 3 m spatial resolution Planet Scope images along offshore China, a total of 129,494 ha of cultured seaweed was identified and delineated with an overall accuracy of 95.70% and a KAPPA index of 0.912, respectively. Then, a seaweed map in offshore China in 2018–2019 was developed. The results provided basic information about seaweed farms in China. The approach reported in this work is accurate and efficient, which can be used to replace the conventional method to obtain the culture seaweed information. This study can be of reference for mapping seaweed on a broader or global scale. [ABSTRACT FROM AUTHOR]

Sea surface temperature (SST) is an important oceanography attribute that has been used to study ocean climatic conditions, ocean dynamics and air-sea interactions. In the present work, the Bayesian maximum entropy (BME) method was used to interpolate a FY-3 C /VIRR satellite dataset in the region with coordinates 120°-150°W and 45°-60°S and during January 2020. A novel approach of constructing valuable soft data was developed by combining BME interpolation with highly correlated SST day and night data differences. The BME interpolation accuracy was assessed by cross-validation, and the results showed that the average RMSE (root mean squared error) was 0.700 and the average bias was 0.441°C. Furthermore, using the Argo data as a basis of comparison, the coverage and accuracy of the BME interpolation of the FY-3 C/VIRR satellite SST dataset were compared numerically with those of the Ordinary Kriging (OK) interpolation of the FY-3 C/VIRR satellite SST dataset and the Optimum Interpolation Sea Surface Temperature (OISST) of the AVHRR satellite SST dataset. It was found that BME had the best SST interpolation performance among the three methods with the lowest average bias and the largest correlation coefficient. Although OISST had a full product coverage rate overall (due to its use of more perfect treatment means), BME's coverage rate (97.5%) considerably improved that of the FY-3 C/VIRR SST data. Also, both the BME and OK products maintained a 12hrs temporal resolution and a 0.05 decimal degrees longitude/latitude spatial resolution, which is an improvement over OISST data with a 24hrs time resolution and a 0.25 decimal degrees longitude/latitude spatial resolution. Another advantage of BME is that because of its broad theoretical support its performance in practice can be improved further as more knowledge sources become available (which can only be incorporated by BME). [ABSTRACT FROM AUTHOR]

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Mutated COX-2 has become the new molecular marker of aspirin resistance. However, there is still a technical 'bottleneck' for direct and sensitive detection of circulating COX-2 mutant gene. In this work, we reported a simple and ultrasensitive electrochemical method for COX-2–765G/C (rs20417) detection for the first time. Polyallylamine (PAA) functionalised Pt nanostructures with long-spined sea urchin-like morphology (Pt-LSSUs@PAA) was synthesised by a simple chemical method for the construction of nano-sensing interface. Ru(NH3)63+ is used as a primary electron acceptor that is electrostatically attracted to peptide nucleic acid modified electrodes and Fe(CN)63− is introduced into the redox system as secondary electron acceptor to regenerate Ru3+ after electrochemical reduction for multiple redox cycles. Different pulse voltammetry was applied to record the electrochemical signals. Under optimal conditions, the DNA sensors showed a wide linear relationship, from 10 fM to 1 nM, with detection limits of 3.3 fM (S/N = 3). This study will provide the basis for the precise use of aspirin, and it has important guiding value for individual drug testing of cardiovascular disease. [ABSTRACT FROM AUTHOR]

Remote sensing is the main approach to map aquatic vegetation, and classification tree (CT) is superior to various classification methods. Based on previous studies, modified CT can be developed from traditional CT by adjusting the thresholds based on the statistical relationship between spectral features to classify different images without ground-truth data. However, no studies have yet employed this method to resolve marine vegetation. In this study, three Gao-Fen 1 satellite images obtained on 30 January 2014, 5 November 2014 and 21 January 2015 were selected, and two features were then employed to extract macroalgae farms. Results show that the overall accuracies of traditional CTs for three images are 92.0, 94.2 and 93.9%, respectively, whereas those of the two corresponding modified CTs for images obtained on 21 January 2015 and 5 November 2014 are 93.1 and 89.5%, respectively. This indicates modified CTs can map macroalgae with multi-date imagery and monitor their spatiotemporal distribution in coastal environments. [ABSTRACT FROM AUTHOR]

China's 55 non-Han ethnic minority groups were at least in part politically and institutionally 'invented' by China's ethnic classification project, and also through the effects of the system of continuous population census. This paper investigates population change of the non-Han ethnic minorities (NHEMs) over the past six decades. The number of NHEMs as a whole tripled from 1953 to 2010. However, growth has differed among individual groups and in different time periods. The population of some groups has fluctuated while that of others has grown steadily, regardless of the size of the groups. As a whole, since 2000 the growth rate of NHEMs has been lower than that of the Han Chinese, and the population of 13 NHEM groups has begun to decline. A growing number of people belonging to ethnic minorities have switched their ethnic identities to Han. This has especially been the case for NHEM youth. The change in ethnic minority populations has been influenced by dynamic interactions among demographic factors, ethnic identification as well as political, economic and policy changes. [ABSTRACT FROM AUTHOR]

Macroalgae plays an important role in coastal ecosystems. The accurate delineation of macroalgae areas is important for environmental management. This study compared the pixel- and object-based methods using Gaofen satellite no. 2 image to explore an efficient classification approach. Expert system rules and nearest neighbour classifier were adopted for object-based classification, whereas maximum likelihood classifier was implemented in the pixel-based approach. Normalized difference vegetation index, normalized difference water index, mean value of the blue band and geometric characteristics were selected as features to distinguish macroalgae farms by considering the spectral and spatial characteristics. Results show that the object-based method achieved a higher overall accuracy and kappa coefficient than the pixel-based method. Moreover, the object-based approach displayed superiority in identifying Porphyra class. These findings suggest that the object-based method can delineate macroalgae farming areas efficiently and be applied in the future to monitor the macroalgae farms with high spatial resolution imagery. [ABSTRACT FROM AUTHOR]

Tourism has been a dynamic and potential industry in China in the recent two decades. However, the rapid development of tourism has caused tremendous ecological pressure. Evaluation of tourism carrying capacity is imperative to have a comprehensive understanding of tourism’s development and sustainability. Ecological footprint (EF) analysis was applied to quantitatively assess the ecological carrying capacity of tourism in the Zhoushan Municipality during the years 2010–2014, and geospatial technologies were used for regional analysis. Results showed that the tourism EF (TEF) and local EF slowly increased between 2010 and 2014. TEF accounted for a remarkable proportion over this five-year period and reached 20–30% of the regional EF. Amongst the four sub-regions, Dinghai appeared to have a relatively large deficit, whereas Shengsi presented a great ecological carrying capacity surplus, thereby revealing a remarkable local imbalance of development. Although the TEF of Zhoushan was slightly over its carrying capacity, the per capital EF of residents remained below average national and global levels. Proper planning and development of tourism at the regional level are suggested as a sound strategy for sustainable development of the Zhoushan Municipality. [ABSTRACT FROM AUTHOR]

National boundaries and border cities have been transformed globally. This is partly due to neoliberal globalisation, the continuous formation of a ‘borderless world’ and partly to the global ‘war on terror’. Darwin, the capital city of the Northern Territory (NT), is on the northern coast of Australia, bordering its overseas Asian neighbours. Far away from the main Australian population centres in the south, the city grows slowly, relying mainly on Australian government investments, infrastructure, and the incorporation of defence programs in the north. The rise of Asia, as well as Australia's increasing economic reliance on Asia, has created new opportunities for Darwin's growth. The development of Asian economies has resulted in growing global investment in resource extraction in NT. Asia, though, has been seen as a key threat in the modern history of Australia. This national sensitivity is underpinned by the global ‘war on terror’ in which Australia is deeply involved. Australia has tight border control regimes and a growing military presence on the northern border area. This paper examines how these co-existing but contradictory dynamics have reshaped the urban development of Darwin City. The consequential social and spatial patterns are identified and discussed. [ABSTRACT FROM AUTHOR]

This paper evaluates the quality characteristics of existing versions of 3-arc-second SRTM and 1-arc-second GDEM over Anji County, Zhejiang, China using reference elevations from a high-quality 1:10 k topographic map. Results show that SRTM has higher accuracy (RMSE =12.44 m) than GDEM (RMSE=14.20 m for Version 1, 12.76 m for Version 2); however, unsatisfactory void filling and an overall 1/2 pixel shift exits in SRTM version 4.1. Although spurious elevations over omitted water bodies still persist, GDEM Version 2 demonstrated significant improvement over Version 1. Accuracies of both SRTM and GDEM decrease on steeper slopes. Aspect also influences both the magnitude and the sign of errors. DEM accuracy in non-forested areas is considerably higher than that in forested areas. SRTM version 4.1 and GDEM version 2 possessed actual spatial resolutions of 90 m, despite both of them failed to match their nominal accuracies. SRTM Version 4.1 could be the first choice, while ASTER GDEM Version 2 would be a good alternative for areas where extensive voids exist in SRTM. [ABSTRACT FROM PUBLISHER]

Satellite remote-sensing technology has shown promising results in characterizing the environment in which plants and animals thrive. Scientists, biologists, and epidemiologists are adopting remotely sensed imagery to compensate for the paucity of weather information measured by weather stations. With measured humidity from three stations as baselines, our study reveals that normalized difference vegetation index (NDVI) and atmospheric saturation deficit at the 780 hPa pressure level (DMODIS), both of which were derived from the Moderate Resolution Imaging Spectroradiometer (MODIS) sensor, were significantly correlated with station saturation deficits (Dstn) (r = 0.42–0.63,p < 0.001). These metrics have the potential to estimate saturation deficits over east Africa. Four to nine days of lags were found in the NDVI responding toDstn. For the daily estimation ofDstn,DMODISyielded better performance than the NDVI. However, both of them poorly explained variation in dailyDstnusing simple regression models (adj.R2 = 0.17–0.39). When the estimation temporal scale was changed to 16 days, performance was similar, and both were better than daily estimations. ForDstnestimation at coarser geographic scales, given that many factors such as soil, vegetation, slope, aspect, and wind speed might complicate NDVI response lags and model construction,DMODISis preferable as a proxy to saturation deficit over ground due to its simple relationship withDstn. [ABSTRACT FROM AUTHOR]

Darwin, the capital of the Northern Territory, is a port city located in Australia's Top End and facing Southeast Asia. The distance from Darwin to Australia's main economic centres of Sydney and Melbourne is almost the same as to Singapore. This central geographical location has inspired the development of the Port and the City of Darwin from time to time while being held back by its remoteness, and especially the lack of an efficient railway link to Australia's major southern centres. The Port of Darwin has been redeveloped with the vision of repositioning the City of Darwin as Australia's gateway to Asia which it was expected to achieve with the completion of the transcontinental railway link from Adelaide to Darwin. This paper analyses trade and cargo movements for the Port of Darwin between 2000 and 2009-5 years for each period before and after the availability of intermodal transport-and examines the processes by which transformation of the gateway is actually occurring. The evidence to date, however, suggests that the landbridge development has had little material effect in terms of trans-shipments and throughputs for the Port of Darwin. The volume of container trade and interstate export and import cargo that passes through the port has in fact declined since the availability of the transcontinental railway in 2005. [ABSTRACT FROM AUTHOR]

Mapping rice cropping areas with optical remote sensing is often a challenge in tropical and subtropical regions because of frequent cloud cover and rainfall during the rice growing season. Synthetic aperture radar (SAR) is a potential alternative for rice mapping because of its all-weather imaging capabilities. The recent Phased Array-type L-band SAR (PALSAR) sensor onboard the Advanced Land Observing Satellite (ALOS) acquires multipolarization and multitemporal images that are highly suitable for rice mapping. In this pilot study, we demonstrate the feasibility of this sensor in mapping the rice planting area in Zhejiang Province, southeast China. High-resolution ALOS/PALSAR images were acquired at three rice growing stages (transplanting, tillering and heading) and were applied in a support vector machine (SVM) classifier to map rice and other land use surfaces. The results show that, based on the 1:10 000 land use/land cover (LULC) survey map, the rice fields can be mapped with a conditional Kappa value of 0.87 and at user's and producer's accuracies of 90% and 76%, respectively. The large commission error primarily came from confusion between rice and dryland crops or orchards because of their similar backscatter amplitudes in the rice growing season. The relatively high rice mapping accuracy in this study indicates that the new ALOS/PALSAR data could provide useful information in rice cropping management in subtropical regions such as southeast China. [ABSTRACT FROM AUTHOR]