Natural Science

Preparation of lignin derivatives and their application as protease adsorbent

基于Kriging模型的地面气温空间插值研究

This paper aims to describe spatial interpolation methods to estimate surface air temperatures (SATs). The SAT at a particular location where SAT observations are not available is estimated through a Kriging interpolation between SAT measurements from 192 meteorological sites at which daily SAT observations have been obtained. A temporal de-trending method based on a Fourier series is used to model and remove the annual trend in original data in order to ensure the stationarity of de-trended data from which kriging parameters are determined. Furthermore, a spatial or surface de-trending in terms of geographic coordinates including altitude, latitude and longitude of each location is adopted in a Kriging model. Besides a Kriging model, an inverse distance weighting (IDW) interpolation method is tested as a comparison. The accuracies of both spatial interpolation approaches are assessed by calculating and comparing their mean absolute error (MAE) and root mean square error (RMSE) when taking each meteorological site as the target location in a cross-validation procedure. The results show that the Kriging model performs better than the IDW method at 174 sites. In addition, the temporal and spatial de-trending methods make the main contribution to the accurate capture of spatial correlations of SATs in the study area in a Kriging process

Letter Ruling 00-15: The Meaning of "Reasonable Transportation Charges"

The effect of plant population density (PPD) and root-induced leaf cytokinin on the compensatory growth of potted corn seedlings during post-drought rewatering was investigated. The study design comprised four treatments: (1) wetness with low PPD, (2) wetness with high PPD, (3) rewatering with low PPD, and (4) rewatering with high PPD. Results showed that drought stress restrained the growth of corns. By contrast, rewatering enhanced the net photosynthetic rate and growth of corns. During the 8 days of rewatering, compensatory growth during post-drought rewatering occurred in corns with high PPD; however, such compensatory growth did not occur in corns with low PPD. Zeatin riboside concentrations in leaves and xylem saps were significantly higher under rewatering treatment than those under wet treatment. High leaf cytokinin concentration accelerated corn growth. The coefficients of variation and Gini-coefficient of wet treatment were significantly higher than those of rewatering treatment under high PPD, demonstrating that intense intraspecific competition occurred in the wet treatment. Extreme intraspecific competition negatively affected net photosynthetic rate. In brief, the interactions between root-induced leaf cytokinin and weak intraspecific competition promoted the compensatory growth under high PPD

ARF1 and GBF1 Generate a PI4P-Enriched Environment Supportive of Hepatitis C Virus Replication

Cellular levels of phosphatidylinositol 4-phosphate (PI4P) have been shown to be upregulated during RNA replication of several viruses, including the HCV replicon model. However, whether PI4P is required in an infectious HCV model remains unknown. Moreover, it is not established whether the host transport machinery is sequestered by the generation of PI4P during HCV infection. Here we found that PI4P was enriched in HCV replication complexes when Huh7.5.1 cells were infected with JFH1. HCV replication was inhibited upon overexpression of the PI4P phosphatase Sac1. The PI4P kinase PI4KIII$\beta$ was also found to be required for HCV replication. Moreover, the vesicular transport proteins ARF1 and GBF1 colocalized with PI4KIIIβ and were both required for HCV replication. During authentic HCV infection, PI4P plays an integral role in virus replication.Version of Recor

Measurement of the quadratic Zeeman shift of ^{85}Rb hyperfine sublevels using stimulated Raman transitions

We demonstrate a technique for directly measuring the quadratic Zeeman shift using stimulated Raman transitions.The quadratic Zeeman shift has been measured yielding [delta][nju] = 1296.8 +/-3.3 Hz/G^{2} for magnetically insensitive sublevels (5S1/2, F = 2,mF = 0 -> 5S1/2, F = 3,mF = 0) of ^{85}Rb by compensating the magnetic eld and cancelling the ac Stark shift. We also measured the cancellation ratio of the differential ac Stark shift due to the imbalanced Raman beams by using two pairs of Raman beams ([sigma]^{+}, [sigma]^{+}) and it is 1:3.67 when the one-photon detuning is 1.5 GHz in the experiment

RNA Viral Community in Human Feces: Prevalence of Plant Pathogenic Viruses

The human gut is known to be a reservoir of a wide variety of microbes, including viruses. Many RNA viruses are known to be associated with gastroenteritis; however, the enteric RNA viral community present in healthy humans has not been described. Here, we present a comparative metagenomic analysis of the RNA viruses found in three fecal samples from two healthy human individuals. For this study, uncultured viruses were concentrated by tangential flow filtration, and viral RNA was extracted and cloned into shotgun viral cDNA libraries for sequencing analysis. The vast majority of the 36,769 viral sequences obtained were similar to plant pathogenic RNA viruses. The most abundant fecal virus in this study was pepper mild mottle virus (PMMV), which was found in high concentrations—up to 10(9) virions per gram of dry weight fecal matter. PMMV was also detected in 12 (66.7%) of 18 fecal samples collected from healthy individuals on two continents, indicating that this plant virus is prevalent in the human population. A number of pepper-based foods tested positive for PMMV, suggesting dietary origins for this virus. Intriguingly, the fecal PMMV was infectious to host plants, suggesting that humans might act as a vehicle for the dissemination of certain plant viruses

catena-Poly[[octa­aqua­bis­(μ4-benzene-1,3,5-tricarboxyl­ato)trizinc] tetra­hydrate]

In the title compound, {[Zn3(C9H3O6)2(H2O)8]·4H2O}n, there are two crystallographically independent ZnII ions. One presents a trigonal-bipyramidal coordination geometry defined by five O atoms [three from two carboxyl­ate groups of two benzene-1,3,5-tricarboxyl­ate (BTC) ligands and the other two deriving from three water mol­ecules], while the other lies on an inversion centre and exists in a slightly distorted octa­hedral coordination geometry defined by six O atoms (two from two carboxyl­ate groups of two BTC ligands and the others from four water mol­ecules). A three-dimensional framework is further strengthened via O—H⋯O hydrogen-bonding inter­actons

Topological states constructed by two different trivial quantum wires

The topological states of the two-leg and three-leg ladders formed by two trivial quantum wires with different lattice constants are theoretically investigated. For the symmetric nearest-neighbor intra-chain hopping two-leg ladder, the inversion symmetry topological insulator phase with two degenerate topological edge states appears. When the inversion symmetry is broken, the topological insulators with one or two topological edge states of different energies and topological metals with edge states embedded in the bulk states could emerge dependent on the filling factor. The topological origin of these topological states in the two-leg ladders is the topological properties of the Chern insulators and Chern metals. According to the arrangement of two trivial quantum wires, we construct two types of three-leg ladders. Each type of the three-leg ladder could be divided into one trivial subspace and one topological nontrivial subspace by unitary transformation. The topological nontrivial subspace corresponds to the effective two-leg ladder model. As the filling factor changes, the system could be in topological insulators or topological metals phases. These rich topological states in the two-leg and three-leg ladders could be confirmed by current experimental techniques