Estimation of evapotranspiration in the Mu Us Sandland of China

Evapotranspiration (ET) was estimated from 1981–2005 over Wushen County located in the Mu Us Sandland, China, by applying the Advection-Aridity model, which is based on the complementary relationship hypothesis. We used National Oceanic and Atmospheric Administration (NOAA) Advanced Very High Resolution Radiometer (AVHRR), Moderate Resolution Imaging Spectroradiometer (MODIS), and meteorological data. Our results show that the estimated daily ET was about 4.5% higher than measurements using an Eddy Covariance (EC) system after forcing energy balance closure over an alfalfa field from 22 July 2004 to 23 August 2004. At a regional scale, the estimated monthly ET was about 8.7% lower than measurements using the EC system after forcing energy balance closure over an alfalfa field in August 2004. These results were about 3.0% higher than ET measurements by microlysimeter over sand dunes during June 1988. From 1981 to 2005, the average annual ET and precipitation levels were 287 mm and 336 mm, respectively, in Wushen County. The average annual ET varied from 230 mm in western parts of Wushen County to 350 mm in eastern parts of the county. Both inter-annual and seasonal variations in ET were substantial in Wushen County. The annual ET was 200–400 mm from 1981–2005, and the seasonal pattern of ET showed a single peak distribution. The cumulative ET during the June–September 2004 period was 250 mm, which was 87% of the total annual ET. The annual ET, precipitation, and the maximum Normalized Difference Vegetation Index (NDVI<sub>max</sub>) showed positive correlations temporally and spatially

The design and investigation of nanocomposites containing dimeric nematogens and liquid crystal gold nanoparticles with plasmonic properties showing a nematic-nematic phase transition (Nᵤ-Nₓ/Ntb)

The construction of liquid crystal compositions consisting of the dimeric liquid crystal, CB_C9_CB (cyanobiphenyl dimer = 1",9"-bis(4-cyanobiphenyl-4'-yl)nonane), and the range of nematic systems is explored. The materials include a laterally functionalized monomer, which was used to construct a phase diagram with CB_C9_CB, as well as one laterally linked dimer liquid crystal material and two liquid crystal gold nanoparticle (LC-Au-NPs) systems. For the Au-NP-LCs, the NP diameters were varied between ~3.3 nm and 10 nm. Stable mixtures that exhibit a nematic-nematic phase transition are reported and were investigated by POM (polarizing optical microscopy), DSC (differential scanning calorimetry) and X-ray diffraction studies

On the Convergence of Ritz Pairs and Refined Ritz Vectors for Quadratic Eigenvalue Problems

For a given subspace, the Rayleigh-Ritz method projects the large quadratic eigenvalue problem (QEP) onto it and produces a small sized dense QEP. Similar to the Rayleigh-Ritz method for the linear eigenvalue problem, the Rayleigh-Ritz method defines the Ritz values and the Ritz vectors of the QEP with respect to the projection subspace. We analyze the convergence of the method when the angle between the subspace and the desired eigenvector converges to zero. We prove that there is a Ritz value that converges to the desired eigenvalue unconditionally but the Ritz vector converges conditionally and may fail to converge. To remedy the drawback of possible non-convergence of the Ritz vector, we propose a refined Ritz vector that is mathematically different from the Ritz vector and is proved to converge unconditionally. We construct examples to illustrate our theory.Comment: 20 page

Analysis of genetic diversity and construction of core collection of local mulberry varieties from Shanxi Province based on ISSR marker

Genetic diversity of 73 local mulberry varieties from Shanxi Province were screened using ISSR markers, with l5 primers combinations selected for their reproducibility and polymorphism. 129 bands were amplified, of which 115 bands showed polymorphism and the ratio of polymorphism bands was 89.15%. Nei’s genetic similarity coefficients ranged from 0.5891 to 0.9457 with an average of 0.7674. The observed number of alleles of each loci, effective number of alleles of each loci, Nei’s gene diversity, Shannon’s information index were 1.8915, 1.4771, 0.2780 and 0.4197, respectively. Clustering results showed that the 73 varieties could be divided into three different groups and nine subgroups. By using stepwise clustering and random methods and the modified heuristic algorithm, 21 core collections were constructed and the ratio of core collection was 28.77%. The result of t-test to the parameters (the number effective of alleles, Nei's genetic diversity index and Shannon's information index) showed that there was not significant difference between the core collection and initial sample with the exception of the number of observed alleles, that is, the core collection could well represent the initial sample.Key words: Mulberry, germplasm resource, genetic diversity, ISSR, cluster analysis, core collection

DecAug: Out-of-Distribution Generalization via Decomposed Feature Representation and Semantic Augmentation

While deep learning demonstrates its strong ability to handle independent and identically distributed (IID) data, it often suffers from out-of-distribution (OoD) generalization, where the test data come from another distribution (w.r.t. the training one). Designing a general OoD generalization framework to a wide range of applications is challenging, mainly due to possible correlation shift and diversity shift in the real world. Most of the previous approaches can only solve one specific distribution shift, such as shift across domains or the extrapolation of correlation. To address that, we propose DecAug, a novel decomposed feature representation and semantic augmentation approach for OoD generalization. DecAug disentangles the category-related and context-related features. Category-related features contain causal information of the target object, while context-related features describe the attributes, styles, backgrounds, or scenes, causing distribution shifts between training and test data. The decomposition is achieved by orthogonalizing the two gradients (w.r.t. intermediate features) of losses for predicting category and context labels. Furthermore, we perform gradient-based augmentation on context-related features to improve the robustness of the learned representations. Experimental results show that DecAug outperforms other state-of-the-art methods on various OoD datasets, which is among the very few methods that can deal with different types of OoD generalization challenges.Comment: Accepted by AAAI202

On Inner Iterations in the Shift-Invert Residual Arnoldi Method and the Jacobi--Davidson Method

Using a new analysis approach, we establish a general convergence theory of the Shift-Invert Residual Arnoldi (SIRA) method for computing a simple eigenvalue nearest to a given target $\sigma$ and the associated eigenvector. In SIRA, a subspace expansion vector at each step is obtained by solving a certain inner linear system. We prove that the inexact SIRA method mimics the exact SIRA well, that is, the former uses almost the same outer iterations to achieve the convergence as the latter does if all the inner linear systems are iteratively solved with {\em low} or {\em modest} accuracy during outer iterations. Based on the theory, we design practical stopping criteria for inner solves. Our analysis is on one step expansion of subspace and the approach applies to the Jacobi--Davidson (JD) method with the fixed target $\sigma$ as well, and a similar general convergence theory is obtained for it. Numerical experiments confirm our theory and demonstrate that the inexact SIRA and JD are similarly effective and are considerably superior to the inexact SIA.Comment: 20 pages, 8 figure

Characterization of the Bafilomycin Biosynthetic Gene Cluster from Streptomyces lohii

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/96305/1/301_ftp.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/96305/2/cbic_201200743_sm_miscellaneous_information.pd

Present-day Geostress Characteristics of the Central Region of the 1605 Qiongshan M 7.5 Earthquake and their Implications for Regional Fault Activity

Continuous subsidence, which has occurred over more than 100 km2 of the Dongzhai Harbor area, northeast Hainan Island, is likely to be associated with tectonic movement arising from the 1605 Qiongshan M 7.5 earthquake. It is the only earthquake in the history of China to have caused large-scale land subsidence into the sea, and the disaster led to the sinking of 72 villages. To understand the dynamic environment of this subsidence, a 300-meter-deep borehole was established on the eastern side of the Puqian town on the east coast of Dongzhai Harbor. A series of 10 in-situ stress measurements and 4 impression orientation measurements were carried out by the hydraulic fracturing method in the borehole. The results show that the maximum horizontal principal stress, SH, is between 5.70 to 12.07 MPa, and the minimum horizontal principal stress, Sh, is between 4.13 to 8.16 MPa. Compared with the magnitude of in-situ stress in the South China coastal area, the magnitude of the in-situ stress for Dongzhai Harbor is considered to be of a medium to upper level. The maximum horizontal principal stress direction is in the northwest direction (33.96°NW). The maximum and minimum horizontal lateral pressure coefficient values are both greater than 1, which indicates that the stress field at the measured point is mainly horizontal, with the principal stress increasing with the depth. The NW-trending principal compressive stress is likely to be one of the dynamic sources of the activity of the Puqian - Qinglan fault and the subsidence of the Dongzhai Harbor graben