Rewarding the Location of Terms in Sentences to Enhance Probabilistic Information Retrieval

In most traditional retrieval models, the weight (or probability) of a query term is estimated based on its own distribution or statistics. Intuitively, however, the nouns are more important in information retrieval and are more often found near the beginning and the end of sentences. In this thesis, we investigate the effect of rewarding the terms based on their location in sentences on information retrieval. Particularly, we propose a kernel-based method to capture the term placement pattern, in which a novel Term Location retrieval model is derived in combination with the BM25 model to enhance probabilistic information retrieval. Experiments on five TREC datasets of varied size and content indicates that the proposed model significantly outperforms the optimized BM25 and DirichletLM in MAP over all datasets with all kernel functions, and excels compared to the optimized BM25 and DirichletLM over most of the datasets in P@5 and P@20 with different kernel functions

Changes of the Wetland Landscape and the Consequent Impacts on the Waterbirds in Western Songnen Plain

AbstractWetland have been shrinking rapidly in area and degrading in functioning. These all hold back the sustainable development of human communities and caused globe changes. Taken Western Songnen Plain as a case study, a series of landscape pattern metrics were selectively used to quantify the wetland changes. The correlation between the acreage losses of wetland and the number of waterbirds was studied based on the statistical data of waterbirds. The results showed that the wetlands had undergone substantial loss in area and fragmented during the nearly 50 years in the study area. The changes of the wetlands exerted impacts on the waterbirds which depend on the wetlands. The waterbirds changed in two ways: Waterbirds dropped rapidly in number at the first stage, then come down gently. Secondly, waterbirds declined gently in number at the first time period, then dropped rapidly. From the study, we concluded that wetlands had been shrinking in area and fragmented and partly accounted for decline and even extinctions of waterbirds during the nearly 50 years during the study period

Bis(4-amino-3,5-di-2-pyridyl-1,2,4-triazole-κ2 N 1,N 5)diaqua­zinc(II) dinitrate

The asymmetric unit of the title compound, [Zn(C12H10N6)2(H2O)2](NO3)2, contains one-half of the complex molecule and one NO3 − anion. The ZnII ion displays a distorted tetra­gonal-pyramidal geometry with four N atoms from two chelating 4-amino-3,5-di-2-pyridyl-1,2,4-triazole (2-bpt) lig­ands in the basal plane and one water mol­ecule occupying the apical site. Another water mol­ecule at the opposite of the apical site has a weak inter­action with the ZnII ion [Zn—O = 2.852 (5) Å]. The ZnII ion and the two water mol­ecules lie on a twofold rotation axis. An extensive system of hydrogen bonds involving the NH2 groups of the 2-bpt ligands, water mol­ecules and nitrate anions links all residues into a three-dimensional network

Cai and Ge, Nitrogen Contents and Its Distribution

Abstract: The nitrogen content of sugar beet plant was significantly positive correlated with nitrogen amount used. At the beginning of beet growing, the distribution of nitrogen was mainly in leaves, but later the distribution rate of nitrogen increased in roots. However, the distribution rate of nitrogen in leaves was still on high level when treated with high amount of nitrogen, which would be against the accumulation of sugar. The contents of phosphorous and potassium of beet plant were also significantly positive correlated with nitrogen amount used, and nitrogen has obvious interaction effect with phosphorus and potassium

Changes in sulfur in soybean rhizosphere soil and the response of microbial flora in a continuous cropping system mediated by Funneliformis mosseae

Soybean is an S-loving crop, and continuous cropping might cause soil sulfur shortage. The primary objectives of this study are to determine whether Funneliformis mosseae (F. mosseae) can enhance the content of available S in S-deficient soil and thereby improve the sulfur utilization rate in soybean. The experiment used Heinong 48 (HN48), a soybean variety with a vast planting area in Heilongjiang Province, and F. mosseae was inoculated in the soil of soybean that had been continuously cropped for 0 and 3 years. The results of the barium sulfur turbidimetric assay show that the sulfur content in the soil and soybean was reduced by continuous cropping and increased by inoculation with F. mosseae; the results of the macro-genome sequencing technology, show that the diversity and abundance of bacteria in the soil was decreased by continuous cropping and increased by inoculation with F. mosseae. The sulfur-oxidizing bacteria (SOB) activity and sulfur-related gene expression levels were lower in the continuous crop group compared to the control group and higher in the F.mosseae-inoculated group compared to the control group. Continuous cropping reduced the sulfur content and ratio of soybean rhizosphere soil, affecting soil flora activity and thus soybean growth; F. mosseae inoculation increased the sulfur content of soybean root-perimeter soil and plants, increased the diversity and abundance of rhizosphere soil microorganisms, increased the expression of genes for sulfur transport systems, sulfur metabolism, and other metabolic functions related to elemental sulfur, and increased the species abundance and metabolic vigor of most SOB. In summary, continuous cropping inhibits soil sulfur uptake and utilization in soybean while the inoculation with F. mosseae can significantly improve this situation. This study offers a theoretical research foundation for using AMF as a bio-fungal agent to enhance soil sulfur use. It also supports the decrease of chemical fertilizers, their substitution, and the protection of native soil

Metformin and Lactic Acidosis in Diabetic Patients

Metformin is the basic drug in the clinical treatment of Diabetes, often used in the treatment of Type 2 Diabetes Mellitus (T2DM).Its effect has been fully verified in the clinical treatment of T2DM. However, in the treatment of T2DM with metformin, there is still a certain probability of related lactic acidosis, and the fatality rate is high. Therefore, is the use of metformin drug treatment a direct risk factor for lactic acidosis in diabetic patients? This paper will review the hypoglycemic mechanism of metformin and related studies on lactic acidosis, so as to further explore the relationship between metformin and lactic acidosis in diabetic patients, and provide help and reference for metformin drugs in the clinical treatment of T2DM

Uncertainty-weighted Multi-tasking for T1ρT_{1\rho} and T2_2 Mapping in the Liver with Self-supervised Learning

Multi-parametric mapping of MRI relaxations in liver has the potential of revealing pathological information of the liver. A self-supervised learning based multi-parametric mapping method is proposed to map T$T_{1\rho}$ and T$_2$ simultaneously, by utilising the relaxation constraint in the learning process. Data noise of different mapping tasks is utilised to make the model uncertainty-aware, which adaptively weight different mapping tasks during learning. The method was examined on a dataset of 51 patients with non-alcoholic fatter liver disease. Results showed that the proposed method can produce comparable parametric maps to the traditional multi-contrast pixel wise fitting method, with a reduced number of images and less computation time. The uncertainty weighting also improves the model performance. It has the potential of accelerating MRI quantitative imaging

Hybrid Structure Based Tracking and Consensus for Multiple Motors

This paper investigates a hybrid structure based synchronous control strategy for multimotor system of shaftless-driven printing press. Many existing algorithms can obtain a stable synchronous system; however, the obtained stable system may encounter a large enough disturbance that can destroy the synchronization. Focusing on this challenging technological problem about how to receive more robust synchronization during steady-state process, this paper first proposes a state-dependent-switching based leader-following control approach, in which synchronization includes two parts, one associated with tracking control for all members, and the other one associated with consensus maintained among followers in the case that one follower loses synchronization with the leader during steady-state motion. By employing the algebra graph theory, matrix theory, and Lyapunov analysis, the convergence and stability of the given multimotor system are proved. Finally, simulation examples are presented to demonstrate the effectiveness and robustness of the theoretical results