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Optics Express Mar 2020In this study, the characterization of Hydrogen Chloride (HCl) seasonal variations and inter-annual linear trend are presented for the first time over the polluted...
In this study, the characterization of Hydrogen Chloride (HCl) seasonal variations and inter-annual linear trend are presented for the first time over the polluted region at Hefei (117°10'E, 31°54'N), China. The time series of HCl were retrieved by the mid-infrared (MIR) solar spectra recorded by the ground-based high-resolution Fourier transform infrared spectroscopy (FTIR) between July, 2015 and April, 2019. The magnitude of HCl reaches a peak in January (2.70 ± 0.16) × 10 molecules*cm and a minimum in September (2.27 ± 0.09) × 10 molecules*cm. The four-year time series of HCl total column show a negative linear trend of (-1.83 ± 0.13) %. The FTIR data are compared with GEOS-Chem data in order to evaluate the performance of the GEOS-Chem model to simulate HCl. In general, total column FTIR data and GEOS-Chem model data are in a good agreement with a correlation coefficient of 0.82. GEOS-Chem model data present a good agreement with FTIR data in seasonal variation and inter-annul trend. The maximum differences occur in January and April with mean differences of 4%-6%. We also present HCl time series observed by 6 NDACC stations (Bremen, Toronto, Rikubetsu, Izana, Reunion.maido, Lauder) in low-middle-latitude sites of the northern and southern hemispheres and Hefei stations in order to investigate the seasonal and annual trends of HCl in low-middle-latitude sites. The HCl total column at the northern hemisphere stations reached the maximum in the late winter or early spring and the minimum in the early winter or late autumn. In general, the seasonal variations of HCl over Hefei is similar to that in other northern hemisphere mid-latitude FTIR stations.
PubMed: 32225437
DOI: 10.1364/OE.384377 -
The Linacre Quarterly Nov 2019Questions of life and death are primarily philosophical questions, as philosopher Robert Spaemann argues. Spaemann argues that "brain death" is philosophically...
UNLABELLED
Questions of life and death are primarily philosophical questions, as philosopher Robert Spaemann argues. Spaemann argues that "brain death" is philosophically unsatisfactory as a definition of death, and as the exclusive criterion for determining death, for two main reasons: first, because it attempts to annul the basic perceptions of the ordinary person in regard to death. Second, because the cause of life and unity in a living being cannot be reduced to the brain. This essay is an explication of Spaemann's contribution to the "brain death" question, which consists in illuminating the philosophical issues at stake.
SUMMARY
This article presents Robert Spaemann's philosophical case that "brain death" suffices neither as a definition of death nor as the sole criterion of death.
PubMed: 32431430
DOI: 10.1177/0024363919876391 -
Scientific Reports Mar 2020Ecological degradation impedes sustainable development in Southwest China, and artificial afforestation has been a key strategy of the Government of China to effectively...
Ecological degradation impedes sustainable development in Southwest China, and artificial afforestation has been a key strategy of the Government of China to effectively curb it. However, the water consumed by large-scale afforestation has a huge impact on water supply in Southwest China, which also arise a new challenge causing severe drought here recently. In order to determine the impact of artificial afforestation on the region, this study conducts spatiotemporal, abrupt change, and correlation and regression analyses. Results show that although water resources fluctuate, they exhibit a general declining trend. Especially after 2000, water resources showed a significant downward trend. In terms of spatial tendency, there has been an obvious decrease in water resources in the Sichuan Basin, the mountainous region of eastern Chongqing, and the Yunnan-Guizhou Plateau. Due to extensive afforestation and vegetation cover growth, there has been an increase in most trends of forest-shrub ecosystems, resulting in substantially enhanced evapotranspiration effects. The uptake of water by afforestation in Southwest China could reach 40.42 billion m, which is equivalent to 10.69% of its annul available water supply (1980-2015). Generally, afforestation disrupts the water balance of the region. This study recommends substituting afforestation for natural restoration or, at the very least, selecting vegetation that requires less water for the restoration of the ecological environment of Southwest China, which provide scientific method for regional sustainable development.
PubMed: 32139773
DOI: 10.1038/s41598-020-61108-w -
Proceedings of the National Academy of... Oct 2015The complement system has evolved to annul pathogens, but its improper regulation is linked with diseases. Efficient regulation of the system is primarily provided by a...
The complement system has evolved to annul pathogens, but its improper regulation is linked with diseases. Efficient regulation of the system is primarily provided by a family of proteins termed regulators of complement activation (RCA). The knowledge of precise structural determinants of RCA proteins critical for imparting the regulatory activities and the molecular events underlying the regulatory processes, nonetheless, is still limited. Here, we have dissected the structural requirements of RCA proteins that are crucial for one of their two regulatory activities, the cofactor activity (CFA), by using the Kaposi's sarcoma-associated herpesvirus RCA homolog Kaposica as a model protein. We have scanned the entire Kaposica molecule by sequential mutagenesis using swapping and site-directed mutagenesis, which identified residues critical for its interaction with C3b and factor I. Mapping of these residues onto the modeled structure of C3b-Kaposica-factor I complex supported the mutagenesis data. Furthermore, the model suggested that the C3b-interacting residues bridge the CUB (complement C1r-C1s, Uegf, Bmp1) and MG2 (macroglobulin-2) domains of C3b. Thus, it seems that stabilization of the CUB domain with respect to the core of the C3b molecule is central for its CFA. Identification of CFA-critical regions in Kaposica guided experiments in which the equivalent regions of membrane cofactor protein were swapped into decay-accelerating factor. This strategy allowed CFA to be introduced into decay-accelerating factor, suggesting that viral and human regulators use a common mechanism for CFA.
Topics: Complement C3b; Complement Factor I; Herpesvirus 8, Human; Humans; Models, Molecular; Multiprotein Complexes; Protein Structure, Quaternary; Protein Structure, Tertiary; Viral Proteins
PubMed: 26420870
DOI: 10.1073/pnas.1506449112 -
Materials Science & Engineering. C,... May 2021The recently proposed concept of quaternary bioreceptivity applies to substrates treated with coating materials and it is considered in the present study with the alga...
The recently proposed concept of quaternary bioreceptivity applies to substrates treated with coating materials and it is considered in the present study with the alga Bracteacoccus minor and the cyanobacterium Nostoc sp. onto granite specimens treated with ethyl silicate and nano-sized silica doped with different amounts of TiO (0, 0.5, 1 and 3 wt%). The findings showed a lack of correlation between the amount of TiO and the level of colonization (main bioreceptivity estimator) to the presence of cracks on the surface, which annul the biocidal power of TiO. Crack formation, which depends on the mechanical properties, greatly influences the bioreceptivity of the material. Thus, the cracks provided anchor points where water is retained, in turn strongly influencing the early stages of colonization kinetics, to a greater extent than the biocidal power of TiO, which will probably increase as the biofilm develops over the entire surface. In addition, although the cracks were more abundant and wider in the ethyl silicate-based consolidant, the nano-sized silica provided better anchoring points, making the material treated with the corresponding consolidant more bioreceptive.
Topics: Biofilms; Construction Materials; Ecosystem; Humans; Titanium
PubMed: 33947552
DOI: 10.1016/j.msec.2021.112058 -
Scientific Reports Oct 2018In this study, the horizontal eddy heat flux in the upper mixed-layer in the South China Sea (SCS) is derived from satellite-derived observational data of sea surface...
In this study, the horizontal eddy heat flux in the upper mixed-layer in the South China Sea (SCS) is derived from satellite-derived observational data of sea surface height anomalies and optimally interpolated sea surface temperature, as well as a reanalysis dataset of mixed-layer depth. The long-term heat flux shows a northward transport on the west side of the SCS, comparable with that in the Kuroshio extension with strong eddy activities. The eddy flux in the SCS has a prominent semi-annual cycle and becomes the strongest in winter and summer with the inflow flux in the south and the outflow in the northwest into the East China Sea through the Taiwan Strait. The semi-annual cycle is related to the strong semi-annul variabilities of the velocity and the temperature in areas southeast of Vietnam and in the northern SCS, respectively. In some areas of the SCS, the eddy heat flux can reach more than ~ 60% of the mean flow heat flux. The convergence of the eddy flux indicates that heat accumulates southeast of Vietnam, which may result in heat storage increases in the upper mixed-layer.
PubMed: 30341357
DOI: 10.1038/s41598-018-33803-2