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Over the past several decades, satellite ocean color remote sensing has greatly improved our understanding of the biogeochemical properties of the global ocean. Particulate organic nitrogen (PON) refers to the nitrogen contained in biological or other debris particles, and it plays important roles in the ecosystem functions and biogeochemical processes of the marine biology. However, few studies have focused on the satellite retrieval of oceanic PON concentrations. With an attempt to fill the gap, this study aimed to explore the feasibility of retrieving oceanic PON concentrations from remote sensing data, determine the bio-optical proxies for satellite PON retrievals, and develop satellite oceanic PON retrieval models for the global ocean. In situ PON data collected over the global ocean and Moderate-resolution Imaging Spectroradiometer (MODIS) Level-3 products were used. Three different types of models were tested: (1) apparent optical property (AOP)-based models, 2) inherent optical property (IOP)-based models, and 3) biological property-based models. Results showed that ocean color remote sensing could be used for oceanic PON concentration retrieval in the global ocean, and AOP-based models calibrated produced better fitting performance than the other two types; models based on blue-to-green band ratio (BG) and normalized difference nitrogen index (NDNI) produced comparable and better fitting and validation performance; and IOP-based and biological property-based models produced lower but also acceptable performance. With the PON models developed, the monthly variations of PON concentrations in the global ocean were also explored. In further studies, PON models will be used to explore oceanic PON spatiotemporal variations and the underlying driving forces.

The complex bone regeneration microenvironment puts high demands on orthopedic implants. The implants are not only desired to satisfy the meeting of the biomechanical properties, but should also possess capabilities to promote osseointegration and bone immune regulation. PEEK is a promising polymeric material for bone implants due to its suitable mechanical properties that well match natural cortical bone tissue. However, its inert biological properties limit its application. As a newly-developed bioactive polysaccharides complex, strontium Eucommia ulmoides polysaccharides (EUP-Sr) has been proved to have capabilities including promoting osteogenesis and regulating bone immunity. In this study, in order to improve the bioactivities of PEEK, we introduce EUP-Sr to the PEEK surface via polydopamine-based coating and form a bioactive PEEK named DPEEK@EUP-Sr. The as-fabricated DPEEK@EUP-Sr was systematically investigated through scanning electron microscopy, X-ray photoelectron spectroscopy, water contact angle analysis to verify the successful introduction of EUP-Sr to PEEK, and in vitro biological experiments including cell proliferation and RT-PCR analysis suggested that the DPEEK@EUP-Sr can effectively promote the proliferation of preosteoblast MC3T3-E1, and exhibit significant anti-inflammation and osteogenesis effects, and so should be beneficial for osteointegration between bone and implants.

Additional file 1: Part I. Detailed information about the main tree species in Guizhou. Table S1. Forest type, dominant tree species (group) (DTSG), and their cover areas in Guizhou in 2016. Part II. Reconstruction of the past forest stand spatial distribution during 1990–2016. Part III. Assumptions for net annual biomass growth increment. Part IV. Detailed parameters for forest carbon (C) stocks estimation in Guizhou using customised CBM-CFS3 model. Table S2. Volume-to-stemwood biomass model parameters by DTSG. Table S3. Multinomial logit model parameters of for fitting proportions of biomass in stemwood, bark, branches and foliage to total tree biomass by DTSG. Table S4. Bamboo biomass per unit area in stemwood, branches, foliage, coarse roots and fine roots at different age. Table S5. Economic forest and shrub forest biomass per unit area in stemwood, other wood, foliage and roots. Table S6. C content values by dominant tree species. Table S7. Decomposition parameters to simulate DOM dynamics. Table S8. Turnover rates of stemwood, other wood, foliage and roots biomass by forest types. Table S9. Default initial values for belowground slow C density on non-forest land (0-100 cm). Table S10. Age group division for DTSG in general arbour forest. Table S11. Age group division for DTSG in short-rotation plantation, and fast-growing/high-yield plantation. Table S12. Age group division for bamboo species. Table S13. Harvest age of DTSG in public welfare forest. Table S14. Harvest age of DTSG in timber plantation. Table S15. Annual C stock and C density of each DTSG in Guizhou from 1990 to 2016. Table S16. Disturbance matrices in Guizhou. Fig. S1. Guizhou spatial unit distribution. Part V. Annual temperature trend during 1990–2016 in Guizhou.

Polypropylene (PP)/sepiolite nanocomposites were prepared using the melt blending technique. The effects of nano-sepiolite content on the mechanical property, thermal property, crystallinity, morphology and rheological property of PP/sepiolite nanocomposites were investigated. The organic modified sepiolites (OSep) were dispersed evenly in PP matrix after surface treatment. The addition of OSep improved the storage modulus and thermal stability, showing a strong interaction between OSep and PP matrix. With the increase of OSep content, the fluidity of PP/OSep composites first increased due to the lubrication of surface modifiers and then decreased due to the interaction between OSep and PP. The size of the toughening agent elastomer first increased and then decreased, and the impact notched strength of PP/Osep composites first decreased and then increased. The loading of OSep also reduced the crystallinity and shrinkage rate of PP. PP/OSep nanocomposites have potential applications in high-performance automotive lightweight materials.

Additional file 1: Table S1. Primer sequences used for qRT-PCR in this study.

This article presents a computer-aided design and computer-aided manufacturing (CAD-CAM) guiding device to facilitate the simultaneous preconditioning and cementation of multiunit porcelain laminate veneers (PLVs). The guiding device was designed from the digital cast of the PLVs and definitive cast assembly, with gingival margins 2 mm from the PLV margins and lingual perforations and milled from a transparent polymethyl methacrylate (PMMA) disk. The PLVs were seated in the guiding device during the preconditioning procedures and transferred to the abutment teeth with luting cement loaded on the intaglio surfaces. Excess resin cement was removed while the guiding device held the PLVs in place. This technique provides predictable, accurate, and efficient simultaneous preconditioning and cementing of PLVs.

Objective The aims of the present study were to observe the changes of cognitive function in a pilocarpine-induced rat model of epilepsy, and to investigate the effects of hippocampal low-frequency stimulation (Hip-LFS) on cognitive function in rats with pharmacoresistant epilepsy. Methods A total of 100 male Sprague Dawley rats were randomly selected to establish an epilepsy model. Rats with successfully induced epilepsy were injected intraperitoneally with phenobarbital and phenytoin for pharmacoresistance selection. The selected pharmacoresistant epileptic (PRE) rats were assigned to a pharmacoresistant control group (PRC group), or a group that received Hip-LFS (LFS group). The same number of rats with pharmacosensitive epilepsy formed the PSC group, and a normal control (NCR) group was included. A novel object recognition (NOR) test, and a Morris water maze (MWM) task were used to assess cognitive function in all groups. Results The epileptic rats showed decreased abilities of learning and memory compared with normal control. The rats in the LFS group displayed significantly shorter escape latency in place navigation, spent longer times in the target quadrant, and traveled longer distances on the platform in the spatial probe test than PRC group. In the NOR test, compared with the PRC group, the discrimination index of the LFS group was significantly increased. Compared with the PRC group, the average frequency and duration of seizures were also decreased in the LFS group. Conclusions The present pilocarpine-induced rat model of epilepsy showed impaired cognitive function, especially in rats with PRE. The Hip-LFS treatment could effectively improve the cognitive function of rats with PRE.

Lakes provide multiple functions to society through commerce,aesthetics,tourism,recreation and biodiversity conservation.Dredging occurs frequently in many lakes,rivers,harbors,or coastal areas to maintain adequate water depths for navigation,provide sand and gravel for construction and reclamation projects,or to remove contaminated sediment to improve water quality and restore the health of aquatic ecosystems.However,long-term and intensive dredging can also cause disturbances to aquatic ecosystems with adverse impacts.Dredging stirs up sediment,increases suspended sediment concentration and reduces water clarity.Thus,dredging alters the physical,chemical and biological properties of the aquatic environment,and further might affect the provision of lake functions.Dredging in Poyang Lake started in 2001.After the activity was banned from the Yangtze River,it increased in Poyang Lake because of the rapidly rising demand for sand in order to support construction in the lower Yangtze River economic zone.The benefits to the local economy are likely to further have persuaded the local government to allow and possibly promote dredging in this lake.Dredging in Poyang Lake was focused at the north of Songmen Mountain before 2010,while the activity has moved to the central parts of Poyang Lake during the most recent two years.However,the distribution of dredging in central Poyang Lake and its impact zone and intensity are not clear.This study,using multi-remote sensing images,aimed to describe the distribution of dredging activities in central Poyang Lake,and further analyze its impact on suspended sediment concentrations(SSC).The Landsat Thematic Mapper(TM) 5 captured on July 28,2011 was employed to identify the dredging-related vessels through visual interpretation.Moderate resolution imaging spectroradiometer(MODIS) images from the Terra satellite taken over the months July-August for three years(2009—2011) combined with a regression model were applied to retrieve the SSC in Poyang Lake,and the before-after-control-impact(BACI) method with three evaluated regions was used to assess the impact of dredging on SSC.Two dredging regions and more than 90 vessels were observed from the TM 5 image in the central Poyang Lake.The MODIS-based SSC values indicated that the SSC increased in the dredging regions and their downstream impact zones from 10 mg/L before dredging to 50 mg/L after the start of dredging.The BACI analyses confirmed that dredging increased the SSC in Poyang Lake by comparing an impacted region with a non-impacted region.Currently,many lakes around the world are suffering a number of problems caused by natural and/or human factors,which may hamper the sustainable developments of multiple lake functions.Remote sensing techniques may provide methods to obtain the spatio-temporal variations of these problems,which will help managers or researchers to analyze and understand the processes and mechanisms in lakes and make sound decisions for lake management.Poyang Lake is an important habitat for several rare or endangered species,such as the baiji(Lipotes vexillifer),Chinese sturgeon(Acipenser sinensis),white sturgeon(Acipenser transmontanus),and Yangtze finless porpoise(Neophocaena phocaenoides).The lake is reputed to be the most important habitat for wintering waterfowl in East Asia,and more than 95% of the Siberian crane(Grus leucogeranus) population winters here.Dredging has seriously affected directly or indirectly the survival of these rare or endangered species.There is an urgent need to balance the relationship between economic development and ecological conservation,minimize the negative effects of dredging and preserve the various productive,environmental and ecological functions provided by Poyang Lake.

Suspended sediment concentration (SSC) is one of important indicators for describing water quality, and obtaining its spatial and temporal distribution information is necessary for understanding, managing and protecting lake ecosystems. This study aimed to developed the Moderate-resolution Imaging Spectroradiometer (MODIS) image-based SSC retrieval model for Lake Poyang, used the model to predict the SSC of Lake Poyang during the flood period from 2000 to 2007, analyzed its spatial and temporal change characteristics and further discussed the causes to induce these changes. The results revealed that: the red band of MODIS Terra was significantly related to the SSC (R2= 0.92, s.e.=12.02mg/L, F=154.30, P0.001), and it may be applied to retrieve the SSC of Lake Poyang during the flood period. The SSC of Lake Poyang showed clear spatial and temporal distribution characteristics from 2000 to 2007, while the SSC had no clear change in the south, increased in the north and fluctuated largely in the centre of the lake. The dredging activities in the northern Lake Poyang was the main cause inducing the increased SSC in this region, and mixed with water backflow from the Yangtze River to Lake Poyang which resulted in the fluctuation of SSC in the centre. Non-significant change of sediments from Rivers Fuhe, Xinjiang and Raohe caused the non-significant change of SSC in the south lake.

Lakes play multiple important functions in economics,tourism,recreation and biodiversity conservation, and the successful performances of these functions are to a great extent influenced by water quality or water clarity. Therefore,monitoring,protecting and improving water clarity are indispensable for keeping the sustainability of these lake functions.This paper,with Lake Poyang National Nature Reserve,China as a case study,aimed to study Landsat TM5 imageries-based retrieval model of water clarity.Using 6 images combined with 13 field meas- ured Secchi Disk Depths (SDD),we developed a regression model between the natural logarithm of SDD and the linear combination of the natural logarithms of TM blue and red bands,i.e.ln(SDD)=-4.016-0.722 In (blue)-0.587 ln( red),which could explain 88% of the SDD variation.12 sampling points were used to validate the developed model.The validating result showed the correlation coefficient between measured and retrieved value was 0.93 and the standard error was equal to 0.22 m.Therefore we believed reasonably that the model achieved an acceptable result.

In order to evaluate the results of Web Based Course on Case Based Learning (CBL) in the Prosthodontics Teaching. In the study, web based prosthodontics course with CBL method was applied to a group of students. And prosthodontics course with traditional teaching method was applied to another group of students. After the course, a questionnaire and an exam were fulfilled by each student. The questionnaire also included the participants attitudes toward the challenges through Web Based CBL course and the suggestion of the education reform. The results showed that there was statistically significant difference on the average scores between 2 groups of students (p

Through analyzing the principle of data sharing in the database system, this paper discusses the principle and method for integrating and sharing GIS data by data engine, introduces a way to achieve the high integration and sharing of GIS data on the basis of VCT in VC++, and provides the method for uniting VCT into RDBMS in order to implement a spatial database with object-oriented data model.

On the basis of an electronic map-based hypermedia data model (EMBHDM), this paper makes a study on the technologies of nonlinear storage, organization, management and browsing of information as well as organization of data on the basis of the relationship between multimedia information of electronic maps. This paper first analyzes some features of electronic maps and hypermedia technology, and then illustrates the creation of EMBHDM with some examples. The tests show that this model can efficiently organize and express multimedia data.

Recently, there have been growing interests in the highspeed multimode fiber (MMF) transmission for the use in the next-generation local area network (LAN). In this paper, a number of optical signal processing techniques are reviewed which allow to realize high-capacity multi-service MMF networks in the user environment.

The provision of food to breeding and migrating waterfowl is one of the major functions of submerged aquatic vegetation in shallow lakes. Vallisneria spiralis L. is a submerged aquatic plant species widely distributed within Jiangxi Poyang Lake National Nature Reserve, China. More than 95% of the world population of the endangered Siberian crane as well as significant numbers of Bewick's swan and swan goose over winter in this area, while foraging on the tubers of Vallisneria. The objective of this paper was to explore the possibility of estimating the aboveground biomass of Vallisneria in Dahuchi Lake using Landsat TM image. The relations between aboveground biomass and the bands of a Landsat TM image and their derived variables were investigated using uni- and multivariate linear and non-linear regression models. The results revealed significant but very weak relations between aboveground biomass and the remotely sensed variables. Hence Landsat TM imagery offered little potential to predict aboveground biomass of Vallisneria in this particular region. Possible reasons which could have caused these results were discussed, including: 1) the possible influence of suspended matter in the water; 2) the less accurate field sampling; 3) the limitations of spatial and spectral resolutions of Landsat TM image; 4) the methods used are not appropriate; 5) the homogeneously spatial distribution of aboveground biomass. We propose considering two alternative methods to improve the estimation of aboveground biomass of Vallisneria. First of all, results might be improved while combining alternative data sources (hyperspectral or high spatial resolution images) with innovative methods and more accurate sampling data; Secondly we propose assessing aboveground biomass while using productivity simulation models of submerged aquatic vegetation integrated with geographic information system (GIS) and remote sensing.