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121.
Zaiqiao Meng Hong Shen Huimin Huang Wei Liu Jing Wang Arun Kumar Sangaiah 《Information processing & management》2018,54(6):1277-1291
Search result diversification is an effective way to tackle query ambiguity and enhance result novelty. In the context of large information networks, diversifying search result is also critical for further design of applications such as link prediction and citation recommendation. In previous work, this problem has mainly been tackled in a way of implicit query intent. To further enhance the performance on attributed networks, we propose a novel search result diversification approach via nonnegative matrix factorization. Our approach encodes latent query intents as well as nodes as representation vectors by a novel nonnegative matrix factorization model, and the diversity of the results accounts for the query relevance and the novelty w.r.t. these vectors. To learn the representation vectors of nodes, we derive the multiplicative updating rules to train the nonnegative matrix factorization model. We perform a comprehensive evaluation on our approach with various baselines. The results show the effectiveness of our proposed solution, and verify that attributes do help improve diversification performance. 相似文献
122.
Computer-based approaches to balancing chemical equations are discussed. Out of 13 methods surveyed, 6 are based on matrix, 2 are interactive programs, 1 is a stand alone system, 1 is developed in algorithm in Basic, 1 is based on design engineering, 1 is written in HyperCard, and 1 prepared for the World Wide Web. Features in addition to balancing chemical equations include the following: solve possible reactions from a list of molecules and ions, determine the number of independent chemical reactions, calculate yields, predict mass relationships, and balance rare reactions. Research and development issues are addressed. 相似文献
123.
Manorama Swain Truptirekha Swain Binoy Kumar Mohanty 《Indian journal of clinical biochemistry : IJCB》2005,20(1):9-17
Background: Autoimmune thyroid disease (AITD), a common organ specific autoimmune disorder is seen mostly in women between
30–50 yrs of age. Thyroid autoimmunity can cause several forms of thyroiditis ranging from hypothyroidism (Hashimoto’s thyroiditis)
to hyperthyroidism (Graves’Disease). Prevalence rate of autoimmune mediated hypothyroidism is about 0.8 per 100 and 95% among
them are women. Graves’ disease is about one tenth as common as hypothyroidism and tends to occur more in younger individuals.
Both these disorders share many immunologic features and the disease may progress from one state to other as the autoimmune
process changes. Genetic, environmental and endogenous factors are responsible for initiation of thyroid autoimmunity. At
present the only confirmed genetic factor lies in HLA complex (HLA DR-3) and the T cell regulatory gene (CTLA 4). A number
of environmental factors like viral infection, smoking, stress & iodine intake are associated with the disease progression.
The development of antibodies to thyroid peroxidase (TPO) thyroglobulin (TG) and Thyroid stimulating hormone receptor (TSH
R) is the main hallmark of AITD. Circulating T Lymphocytes are increased in AITD and thyroid gland is infiltrated with CD4+
and CD8+ T Cells. Wide varieties of cytokines are produced by infiltrated immune cells, which mediate cytotoxicity leading
to thyroid cell destruction. Circulating antibodies to TPO and TG are measured by immunofluorescense, hemagglutination, ELISA
& RIA. TSHR antibodies of Graves’ disease can be measured in bioassays or indirectly in assays that detect antibody binding
to the receptor. 相似文献
124.
Ajay Kumar 《Resonance》2011,16(1):61-64
According to similarity property principle, structurally similar molecules tend to have similar properties. Similar molecules
exhibit similar biological activities. However, there is no hard and fast rule that the compounds with similar chemical structure
will have similar functions. There are several compounds of similar chemical structure with significantly different biological
actions and activities. Structure similarity of natural products can be investigated using Tanimoto coefficient and Euclidean
distance measurements. To do this, the molecules are decomposed into smaller fragments, and a dictionary, of the fragments
are prepared. Using the dictionary, 2D fingerprints are formed. With the fingerprints Tanimoto coefficient and Euclidean distance
are quantitated. 相似文献
125.
126.
The living system on earth is largely using oxygen for burning metabolic fuel for energy. The toxicity of oxygen is largely due to the formation of free radicals in living systems. Stress is also responsible for the generation of free radicals. The evidence for the involvement of free radicals and oxidative injury in producing metabolic disturbance, maladjustment and many diseases has been accumulating since long. It is largely believed that the root cause of many chronic diseases is stress induced free radicals and resultant oxidative injury. 相似文献
127.
128.
Vashist SK Kaur I Bajpai RP Bharadwaj LM Tewari R Raiteri R 《Journal of Zhejiang University. Science. B》2006,7(9):683-685
We report an important observation that the surface conductivity of antibody layer immobilized on polylysine-coated glass
substrate decreases upon the formation of complex with their specific antigens. This change in conductivity has been observed
for both monoclonal and polyclonal antibodies. The conductance of monoclonal mouse IgG immobilized on polylysine-coated glass
substrate changed from 1.02×10−8 Ω−1 to 1.41×10−11 Ω−1 at 10 V when complex is formed due to the specific biomolecular interactions with rabbit anti-mouse IgG F(ab′)2. Similar behavior was observed when the same set up was tested in two clinical assays: (1) anti-Leishmania antigen polyclonal
antibodies taken from Kala Azar positive patient serum interacting with Leishmania promastigote antigen, and (2) anti-p21
polyclonal antibodies interacting with p21 antigen. The proposed concept can represent a new immunodiagnostic technique and
may have wide ranging applications in biosensors and nanobiotechnology too. 相似文献
129.
Sanyal N Pramanik SK Pal R Chowdhury A 《Journal of Zhejiang University. Science. B》2006,7(3):202-208
Two sulfonylurea herbicides, metsulfuron methyl (Ally 20 WP) and chlorimuron ethyl (Classic 25 WP) were evaluated for their dissipation bchaviour in alluvial, coastal saline and laterite soils under laboratory incubated condition at 60% water holding capacity of soils and 30 ℃ temperature was maintained. In field study herbicides were applied twice for the control of grasses, annual and perennials broad leaves weeds and sedges in rice, wheat and soybean to find out the residual fate of both the herbicides on different matrices of respective crops after harvest. Extraction and clean up methodologies for the herbicides were standardized and subsequently analyzed by HPLC. The study revealed that the half-lives of metsulfuron methyl and chlorimuron ethyl ranged from 10.75 to 13.94 d irrespective of soils and doses applied. Field trials with rice, wheat and soybean also revealed that these two herbicides could safely be recommended for application as no residues were detected in the harvest samples. 相似文献
130.
Goswami BK Pandey RK Rathour KS Bhattacharya C Singh L 《Journal of Zhejiang University. Science. B》2006,7(11):873-875
INTRODUCTION Tomato (Lycopersicon esculentum, Mill.), an important vegetable crop is heavily attacked by root knot nematode, Meloidogyne spp. For the manage-ment of root knot nematodes although chemical nematicides were used till 1982, due to their high cost, toxic effect on beneficial soil borne microorganism and carcinogenic effect on human beings alternative approaches are practiced mainly through eco-friendly means like biological control agents, organic amendments, etc. (Singh and … 相似文献