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Fatemeh Lashkari Ebrahim Bagheri Ali A. Ghorbani 《Information processing & management》2019,56(3):733-755
Traditional information retrieval techniques that primarily rely on keyword-based linking of the query and document spaces face challenges such as the vocabulary mismatch problem where relevant documents to a given query might not be retrieved simply due to the use of different terminology for describing the same concepts. As such, semantic search techniques aim to address such limitations of keyword-based retrieval models by incorporating semantic information from standard knowledge bases such as Freebase and DBpedia. The literature has already shown that while the sole consideration of semantic information might not lead to improved retrieval performance over keyword-based search, their consideration enables the retrieval of a set of relevant documents that cannot be retrieved by keyword-based methods. As such, building indices that store and provide access to semantic information during the retrieval process is important. While the process for building and querying keyword-based indices is quite well understood, the incorporation of semantic information within search indices is still an open challenge. Existing work have proposed to build one unified index encompassing both textual and semantic information or to build separate yet integrated indices for each information type but they face limitations such as increased query process time. In this paper, we propose to use neural embeddings-based representations of term, semantic entity, semantic type and documents within the same embedding space to facilitate the development of a unified search index that would consist of these four information types. We perform experiments on standard and widely used document collections including Clueweb09-B and Robust04 to evaluate our proposed indexing strategy from both effectiveness and efficiency perspectives. Based on our experiments, we find that when neural embeddings are used to build inverted indices; hence relaxing the requirement to explicitly observe the posting list key in the indexed document: (a) retrieval efficiency will increase compared to a standard inverted index, hence reduces the index size and query processing time, and (b) while retrieval efficiency, which is the main objective of an efficient indexing mechanism improves using our proposed method, retrieval effectiveness also retains competitive performance compared to the baseline in terms of retrieving a reasonable number of relevant documents from the indexed corpus. 相似文献
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Fatemeh Moghaddam Tabrizi Firouz Ghaderi Pakdel 《Indian journal of clinical biochemistry : IJCB》2014,29(2):174-180
Concentrations of various trace elements are altered during pregnancy with changes in the mother’s physiology and the requirements of growing fetus. The aim of the present longitudinal study was to learn the changes of micronutrients Iron (Fe), Calcium (Ca), zinc (Zn) Magnesium (Mg) and copper (Cu) of pregnant woman and their relations with newborns levels. Serum levels of iron, calcium, zinc, magnesium and copper of 162 pregnant women and their newborns were determined by an inductively couple plasma mass spectrometer (ICP/MS). The results showed that majority (41 %) of pregnant women were in age group 26–36 years 55 % had high school and diploma levels of education and the total income ranged between 3 and 5 Rials million per month There was significant difference in iron levels during first, second and third trimesters, 76.0 ± 17.8, 63.5 ± 15.2 and 70.1 ± 14.4 μg/dl respectively. Significant difference was shown in zinc levels 79.5 ± 15, 74.5 ± 16.1, and 65.3 ± 14.9 μg/dl during three trimesters. Copper levels during pregnancy were significantly different (130.9 ± 43.5, 172.0 ± 38.94, 193.2 ± 28.5 μg/dl. The serum levels of calcium and magnesium during pregnancy were constant (Ca: 8.96 ± 0.48, 8.86 ± 0.47, 8.91 ± 0.42 mg/dl and Mg: 2.10 ± 0.21, 2.08 ± 0.28, 2.09 ± 0.29 mg/dl). Results showed that 13 % of pregnant women had hypocalcaemia and hypomagnesaemia. Thirty eight percent and 42 % of pregnant women had iron and zinc deficiency respectively. In this study, unlike zinc, no pregnant women were found deficient in serum copper levels. Calcium, iron, zinc, copper and magnesium levels in the newborn’s cord blood were 8.93 ± 0.43, 106.0 ± 26.1, 85.35 ± 16.6, 57.04 ± 13.8 and 1.99 ± 0.27 mg/dl respectively. In the present study the levels of iron and zinc in cord blood were higher than the levels of iron and zinc in maternal serum. The mean level of copper in cord blood serum in the current study was lower than maternal values. The mean serum calcium and magnesium in the serum cord blood and in the serum of the pregnant women were similar. 相似文献
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Seyed Ebrahim Alavi Hamidreza Mansouri Maedeh Koohi Moftakhari Esfahani Fatemeh Movahedi Azim Akbarzadeh Mohsen Chiani 《Indian journal of clinical biochemistry : IJCB》2014,29(2):150-153
In the present study, paclitaxel was archaeosomed to reduce side effects and improve its therapeutic index. Carriers have made a big evolution in treatment of many diseases in recent years. Lipid carriers are of special importance among carriers. Archaeosome is one of the lipid carriers. Paclitaxel is one of the drugs used to treat breast cancer which has some unwanted side effects despite its therapeutic effects. Archaeosomes were extracted from methanogenic archi bacteria and synthesized with a certain ratio of paclitaxel in PBS. The mean diameter of archaeosomal paclitaxel was measured by Zeta sizer instrument, Drug releasing of archaeosomal paclitaxel was examined within 26 h which results showed that the most drug releasing occurs during first 3 h. The cytotoxicity effect of archaeosomal paclitaxel on breast cancer’s cell line was evaluated by MTT assay which results showed that the cytotoxicity effect of archaeosomal paclitaxel on breast cancer’s cell line is more than that of the standard paclitaxel formulation. The results indicated that new drug delivery of paclitaxel using archaeosome, increases the therapeutic index of the drug. 相似文献
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Seyed Kazem Bagherpour Doun Sohrab Halal Khor Dardi Qujeq Hasan Ebrahimi Shahmabadi Seyed Ebrahim Alavi Fatemeh Movahedi Azim Akbarzadeh 《Indian journal of clinical biochemistry : IJCB》2014,29(2):242-245
Cisplatinum (Cispt) is an anti-cancer drug with a low level of solubility. One of Cispt’s solvents is dimethyl sulfoxide (DMSO) which can be substituted with chlorine of drug as Cispt’s solvent. Applying such a solvent in biological studies is impossible due to intense reduction in activity. On the other hand, it is specified that Cispt’s stability is increased in aqueous media by increasing sodium chloride (NaCl) concentration up to 0.9 %. Consequently, we intended to study the effect of DMSO on cytotoxicity of Cispt in presence of sodium. MTT assay was employed to study cytotoxicity effect of Cispt + NaCl + DMSO and Cispt + DMSO on G-292 cell line. Cytotoxicity in dilutions of 300 and 9 (p < 0.01) of Cispt in Cispt + NaCl + DMSO formulation was equal to 78 and 7 %. These values were estimated 79 and 18 % for Cispt + DMSO formulation and 79 and 24 % for free drug. IC50 values demonstrated reduction of 45 % in cytotoxicity of Cispt in Cispt + DMSO formulation. Studying chemical structure of Cispt and Cispt dissolved in DMSO showed that NaCl cannot inhibit inactivating effect of DMSO on Cispt and effect of this solvent on Cispt is independent from presence of NaCl. Results represented that using NaCl does not result in stability and keeping cytotoxicity properties of Cispt in DMSO. Findings suggest more studies for using DMSO as a solvent of Cispt. 相似文献
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The purpose of this study is to test the mediating role of teachers?? self-efficacy beliefs in the relationship between sources of efficacy information and students achievement. For achieving this aim, this study suggests two alternative models, tested by Structural equation modeling (SEM) technique. In the first model, sources of efficacy information and teachers?? sense of self-efficacy independently influenced student achievement. In second model, we examined a dependent 2-factor model, consisting of: (a) antecedent variable: sources of efficacy information, (b) mediator variable: teachers?? sense of self-efficacy, and (c) criterion variable: student??s achievement. Among 284 teachers who participated in this study, Sources of the Self-Efficacy Inventory (SOSI) and Teachers?? Sense of Efficacy Scale (TSES) were distributed. Findings of this study indicated that between two suggested models, the dependent model showed the best overall fit to the data. In this model, teachers?? self-efficacy had mediational role between sources of teachers?? self-efficacy and student??s achievement. 相似文献
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Maedeh Koohi Moftakhari Esfahani Seyed Ebrahim Alavi Fatemeh Movahedi Fatemeh Alavi Azim Akbarzadeh 《Indian journal of clinical biochemistry : IJCB》2013,28(4):358-360
Regarding that the breast cancer is the most prevalent disease among women, paclitaxel, an anti-cancer drug, could be used in treatment of this disease. As paclitaxel has adverse effects, it was used of nanoliposome drug delivery technology in order to reduce adverse effects and improve drug efficacy. Certain ratios of phosphatidylcholine, cholesterol and paclitaxel were synthesized to prepare nanoliposomal paclitaxel. Using Zeta sizer device, the mean diameter of nanoliposomal paclitaxel was obtained 421.4 nm and its encapsulation efficiency was 91.3 %. By dialysis, drug release in nanoliposome paclitaxel formulation within 28 h was studied which was 5.53 %. This study showed that cytotoxicity effect of nanoliposomal paclitaxel is more than that of the standard form. 相似文献
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Ahmad Sadeghi Iran Baghban Fatemeh Bahrami Ahmad Ahmadi Peter Creed 《International Journal for Educational and Vocational Guidance》2011,11(1):29-38
A short 33-item form of the Career Development Inventory was validated on a sample of 310 Iranian high school students. Factor
analysis indicated that attitude and cognitive subscale items loaded on their respective factors, and that internal reliability
coefficients at all levels were satisfactory to good. Support for validity was demonstrated by associations in the expected
direction for career decidedness and career decision-making self-efficacy. This short form of the inventory shows promise
as a measure of career maturity with students from a non-Western country. 相似文献
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