66 research outputs found
Study on the Spatial Dynamic Change of Tidal Flat in the Pearl River Estuary from 1990 to 2020
This paper Based on GIS and remote sensing analysis methods, it uses multi-source remote sensing data to obtain the coastal mudflat change and land cover/land use change data of the the Pearl River Estuary Bay Area in 1990, 2005 and 2020. This paper studies the temporal and spatial change characteristics of the coastline in the the Pearl River Estuary Bay Area in three periods, the temporal and spatial pattern change of land use, and the relationship between the two, and summarizes their change rule and causes
Lonicera japonica polysaccharides attenuate ovalbumin-induced allergic rhinitis by regulation of Th17 cells in BALB/c mice
Lonicera japonica Thunb. has been widely used as food ingredients and healthy drinks in the Asian countries,
which was reported to possess some good activities. However, it remains unknown in the immunomodulation of
Lonicera japonica polysaccharides (LJP) on allergic rhinitis (AR). This study aimed to investigate the impact of
LJP on ovalbumin-induced AR in BALB/c mice model. LJP significantly inhibited AR symptoms and eosinophil
number in nasal mucosa. Besides, the increased serum levels of IgE, TNF-α, IL-1β and IL-17 were markedly
decreased when AR mice were treated with LJP. The mRNA expression levels of IL-4, IL-5, IL-6, IL-17, IL-23,
ROR-γt and STAT3 in OVA group were increased, and SOCS3 was reduced, while LJP inhibited the changes. The
present study indicated that LJP suppressed the inflammatory response in AR sensitized by ovalbumin, showing
that LJP has the potential to treat AR through the regulation of Th17 cells
Metagenomic Sequencing Identifies Highly Diverse Assemblages of Dinoflagellate Cysts in Sediments From Ships\u27 Ballast Tanks
Ships\u27 ballast tanks have long been known as vectors for the introduction of organisms. We applied next-generation sequencing to detect dinoflagellates (mainly as cysts) in 32 ballast tank sediments collected during 2001-2003 from ships entering the Great Lakes or Chesapeake Bay and subsequently archived. Seventy-three dinoflagellates were fully identified to species level by this metagenomic approach and single-cell polymerase chain reaction (PCR)-based sequencing, including 19 toxic species, 36 harmful algal bloom (HAB) forming species, 22 previously unreported as producing cysts, and 55 reported from ballast tank sediments for the first time (including 13 freshwater species), plus 545 operational taxonomic units (OTUs) not fully identified due to a lack of reference sequences, indicating tank sediments are repositories of many previously undocumented taxa. Analyses indicated great heterogeneity of species composition among samples from different sources. Light and scanning electron microscopy and single-cell PCR sequencing supported and confirmed results of the metagenomic approach. This study increases the number of fully identified dinoflagellate species from ballast tank sediments to 142 (\u3e 50% increase). From the perspective of ballast water management, the high diversity and spatiotemporal heterogeneity of dinoflagellates in ballast tanks argues for continuing research and stringent adherence to procedures intended to prevent unintended introduction of non-indigenous toxic and HAB-forming species
Gender-Role Based Differences in Time Allocation: A Case Study of Shenzhen, China
Previous studies on daily time allocation have shed light on individuals\u2019 trade-offs regarding time allocation within a fixed time budget. However, interpersonal interactions of time allocation with a social network are far from being understood, largely due to limited research in this area. Further, few studies have focused on residents of China, whose population is largest in the world and whose culture is quite different from western countries. Using the data collected from 261 households in Shenzhen, this study applies structural equations models to investigate time allocation of male and female household heads on the weekday and weekend. The results show clear household activity roles of Chinese residents: men are dominant in out-of-home activities, but women dominate in-home activities. This study also offers some insightful interpersonal interactions of activity participation between household heads
Optical Imaging of Visual Cortical Responses Evoked by Transcorneal Electrical Stimulation With Different Parameters
Citation: Ma Z, Cao P, Sun P, et al. Optical imaging of visual cortical responses evoked by transcorneal electrical stimulation with different parameters. Invest Ophthalmol Vis Sci. 2014;55:5320-5331. DOI: 10.1167/iovs.14-14600 PURPOSE. The use of phosphenes evoked by transcorneal electrical stimulation (TcES) has been proposed as a means of residual visual function evaluation and candidate selection before implantation of retinal prostheses. Compared to the subjective measures, measurement of neuronal activity in visual cortex can objectively and quantitatively explore their response properties to electrical stimulation. The purpose of this study was to investigate systematically the properties of cortical responses evoked by TcES. METHODS. The visual cortical responses were recorded using a multiwavelength optical imaging of intrinsic signals (OIS) combining with electrophysiological recording by a multichannel electrode array. The effects of different parameters of TcES on cortical responses, including the changes of hemoglobin oxygenation and cerebral blood volume, were examined. RESULTS. We found consistent OIS activation regions in visual cortex after TcES, which also showed strong evoked field potentials according to electrophysiological results. The OIS response regions were located mainly in cortical areas representing peripheral visual field. The extent of activation areas and strength of intrinsic signals were increased with higher current intensities and longer pulse widths, and the largest responses were acquired in the frequency range 10 to 20 Hz. CONCLUSIONS. Use of TcES through the ERG-jet corneal electrode may preferentially activate peripheral retina. Revealing the hemodynamic changes in visual cortex occurred after electrical stimulation can contribute to comprehension of neurophysiological underpinnings underlying prosthetic vision. This study provided an objective foundation for optimizing parameters of TcES and would bring considerable benefits in the application of TcES for assessment and screening in patients
Effects of different three-dimensional electrodes on epiretinal electrical stimulation by modeling analysis
Robust estimation of bacterial cell count from optical density
Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals <1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data
Analytical Methods of Voltage Stability in Renewable Dominated Power Systems: A Review
The ongoing development of renewable energy and microgrid technologies has gradually transformed the conventional energy infrastructure and upgraded it into a modernized system with more distributed generation and localized energy storage options. Compared with power grids utilizing synchronous generation, inverter-based networks cannot physically provide large amounts of inertia, which means that more advanced and extensive studies regarding stability considerations are required for such systems. Therefore, appropriate analytical methods are needed for the voltage stability analysis of renewable-dominated power systems, which incorporate a large number of inverters and distributed energy sources. This paper provides a comprehensive literature review of voltage stability analyses of power systems with high levels of renewable energy penetration. A series of generalized evaluation schemes and improvement methods relating to the voltage stability of power systems integrated with various distributed energy resources are discussed. The existing voltage stability analysis methods and corresponding simulation verification models for microgrids are also reviewed in a systematic manner. The traditional and improved voltage stability analysis methods are reviewed according to the microgrid operation mode, the types of distributed generators, and the microgrid configurations. Moreover, the voltage stability indices, which play a crucial role in voltage stability assessments, are critically evaluated in terms of the applicable conditions. The associated modeling and simulation techniques are also presented and discussed. This contribution presents guidelines for voltage stability analysis and instability mitigation methods for modern renewable-rich power systems
The Empirical Analysis of Environmental Regulation’s Spatial Spillover Effects on Green Technology Innovation in China
Green technology innovation is one of the driving forces of industrial structure upgrading. This innovation is thought to be related to environmental regulation. The study uses panel data for 30 Chinese provinces and cities from 2009 to 2020 and presents a comprehensive research-based explanation of how environmental regulations impact green innovation. This study employs the spatial Durbin model to analyze the spillover effect of the region. The results show that the total impact of environmental regulations is 0.223%, of which the direct effect is 0.099%. This impact includes the effects of both formal and informal environmental regulation. It indicates that ecological regulations significantly enhance green technology innovation. Furthermore, the spatial spillover effect is significantly positive at the 1% level with a coefficient of 0.124. Such spillover effects represent a learning effect of regional environmental regulation. Based on the results, the study suggests a few policy measures based on the detailed outcomes
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