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101.
Hemendra Basu Steven Pernecky Aditi Sengupta George U. Liepa 《Journal of the American Oil Chemists' Society》2006,83(12):985-997
At the present time the primary cause of death of most Americans is cardiovascular disease. Approximately 20 million Americans
are currently being treated with some form of statin drugs as a means to lower their blood cholesterol levels, and many of
these same people also consume some combination of omega-3 FA, aspirin, and alcohol/red wine because of clinical data indicating
that each of these, taken alone, seems to improve mortality. Recent studies with omega-3 FA have demonstrated a positive impact
on mortality from coronary heart disease as well as from “all causes,” and this article compares their metabolic benefits
with those of aspirin, alcohol/red wine, and statin drugs. The article suggests that these four compounds may have synergistic
qualities and that clinical trials to study this possibility are warranted. 相似文献
102.
Thiolated starch-coated iron oxide nanoparticles containing curcumin were developed to investigate their cytotoxicity on lymphocytes and cancer cell lines. These nanoparticles were prepared using different concentrations of thiolated starch to study the effect of polymer coating on various properties of nanoparticles, namely, yield percentage, particle size, drug encapsulation, etc. Zeta potential confirmed the stability of nanoparticles. The nanoparticles with 5% polymer coating showed drug encapsulation efficiency up to 78%, while loading efficiency was higher than 80%. The cytotoxicity assay revealed excellent compatibility of the system with lymphocyte cells while considerable amount of cytotoxicity on cancer cell lines. 相似文献
103.
Aspect category detection (ACD) is an important subtask of aspect-based sentiment analysis (ABSA). It is a challenging problem due to subjectivity involved in categorization, as well as the existence of overlapping classes. Among various approaches that have been applied to ACD include rule-based approaches along with other machine learning approaches, and most of them are statistical in nature. In this article, we have used an association rule-based approach. To deal with the statistical limitation of association rules, we proposed a hybridized rule-based approach that combines association rules with the semantic association. For semantic associations, we have used the notion of word-embeddings. Experiments were performed on SemEval dataset, a standard benchmark dataset for aspect categorization in the restaurant domain. We observed that semantic associations can complement statistical association and improve the accuracy of classification. The proposed method performs better than several state-of-the-art methods. 相似文献
104.
Liang Zhu Xiong Peng Shun‐Li Shang Michael T. Kwasny Tawanda J. Zimudzi Xuedi Yu Nayan Saikia Jing Pan Zi‐Kui Liu Gregory N. Tew William E. Mustain Michael Yandrasits Michael A. Hickner 《Advanced functional materials》2019,29(26)
Although the peak power density of anion exchange membrane fuel cells (AEMFCs) has been raised from ≈0.1 to ≈1.4 W cm?2 over the last decade, a majority of AEMFCs reported in the literature have not been demonstrated to achieve consistently high performance and steady‐state operation. Poly(olefin)‐based AEMs with fluorine substitution on the aromatic comonomer show considerably higher dimensional stability compared to samples that do not contain fluorine. More importantly, fluorinated poly(olefin)‐based AEMs exhibit high hydroxide conductivity without excessive hydration due to a new proposed mechanism where the fluorinated dipolar monomer facilitates increased hydroxide dissociation and transport. Using this new generation of AEMs, a stable, high‐performance AEMFC is operated for 120 h. When the fuel cell configuration is subjected to a constant current density of 600 mA cm?2 under H2/O2 flow, the cell voltage declines only 11% (from 0.75 to 0.67 V) for the first 20 h during break‐in and the cell voltage loss is low (0.2 mV h?1) over the subsequent 100 h of cell testing. The ease of synthesis, potential for low‐cost commercialization, and remarkable ex situ properties and in situ performance of fluoropoly(olefin)‐based AEM renders this material a benchmark membrane for practical AEMFC applications. 相似文献
105.
Saifur Rahman Helen K. Saikia 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2013,17(7):1253-1262
In this paper, t-norm based intuitionistic fuzzy submodules are defined, and their various properties are investigated. We also show that if an intuitionistic fuzzy set of a module is an intuitionistic fuzzy submodule with respect to a t-norm, then it is also an intuitionistic fuzzy submodule with respect to the annihilation t-norm. We investigate the nature of intuitionistic fuzzy submodules of a module with the help of their respective cut sets. We obtain some results based on (α, β)-level sets and t-norm based α-cut sets of an intuitionistic fuzzy submodule with respect to a t-norm T. 相似文献
106.
Raghavendar Chikkonda Arun Ravindran Sumeer Saikia Akhil Raman Thankamani Sathyanathan Arout Chelvane Angappane Subramanian James Raju Kanakkappillavila Chinnayya Ramesh Babu Gangineni 《应用聚合物科学杂志》2021,138(11):50018
Ferroelectric switching dynamics of polyvinylidene fluoride (PVDF) thin films in Cu or (Ag/Cu)/PVDF/Cu capacitors are explored by varying PVDF film thickness, applied electric field amplitude (4.35–87.5 MV/m) and frequency (100 mHz–200 Hz). Comprehending spontaneous polarization and its dependence upon interfaces, an electric field is critical for organic ferroelectric memory devices. In this article, quasi-static current–voltage, and polarization–electric field measurements are used to explain the relationship between the coercive field, signal amplitude, and frequency. The observed coercivity enhancement at lower PVDF film thicknesses and with rising frequencies of the applied signal is discussed with Kolmogorov-Avrami-Ishibashi domain nucleation and growth model. The relation between domain growth and the top electrode layer is further discussed from the exponent parameters. 相似文献
107.
Evaluation of Soy Lecithin as Eco‐Friendly Biosurfactant Clathrate Hydrate Antiagglomerant Additive
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Hydrate plug formation is one of the most challenging problems in upstream oilfields. The most preferred option to prevent hydrate plug formation is the use of antiagglomerants in the oil/gas flowlines and in drilling fluids. Antiagglomerants do not prevent hydrate formation but restrict the hydrate crystals from agglomerating. In this study, experiments were conducted on of soy lecithin (biosurfactant) at different concentrations to measure its effectiveness as an antiagglomerant additive. In all the experiments, tetrahydrofuran (THF) hydrate was used, and to study the antiagglomerant efficiency of the additive, visual observation was utilized. Soy lecithin was compared with cetyltrimethylammonium bromide (CTAB), and the former was found as a good environmentally friendly antiagglomerant additive. Soy lecithin at 0.1 wt% in the experimental solution increased the agglomeration time of hydrate crystals by more than 1440 min and showed agglomeration state III at 1 °C. Soy lecithin at 0.01 wt% increased the agglomeration time of hydrate crystals to 1000 min. The effect of soy lecithin on the rheological characteristics and filtration properties of drilling fluid was also studied. Even at the highest concentration of 1.0 wt% soy lecithin and at a temperature of 1 °C, the rheological parameters of the drilling fluid remained within permissible limits. Soy lecithin was thus found to effectively restrict the agglomeration of hydrate crystals. 相似文献
108.
Aditi Jain Nandita Dasgupta Chidambaram Ramalingam 《Critical reviews in food science and nutrition》2018,58(2):297-317
Nanotechnology has seen exponential growth in last decade due to its unique physicochemical properties; however, the risk associated with this emerging technology has withdrawn ample attention in the past decade. Nanotoxicity is majorly contributed to the small size and large surface area of nanomaterials, which allow easy dispersion and invasion of anatomical barriers in human body. Unique physio-chemical properties of nanoparticles make the investigation of their toxic consequences intricate and challenging. This makes it important to have an in-depth knowledge of different mechanisms involved in nanomaterials's action and toxicity. Nano-toxicity has various effects on human health and diseases as they can easily enter into the humans via different routes, mainly respiratory, dermal, and gastrointestinal routes. This also limits the use of nanomaterials as therapeutic and diagnostic tools. This review focuses on the nanomaterial–cell interactions leading to toxicological responses. Different mechanisms involved in nanoparticle-mediated toxicity with the main focus on oxidative stress, genotoxic, and carcinogenic potential has also been discussed. Different methods and techniques used for the characterization of nanomaterials in food and other biological matrices have also been discussed in detail. Nano-toxicity on different organs—with the major focus on the cardiac and respiratory system—have been discussed. Conclusively, the risk management of nanotoxicity is also summarized. This review provides a better understanding of the current scenario of the nanotoxicology, disease progression due to nanomaterials, and their use in the food industry and medical therapeutics. Briefly, the required rules, regulations, and the need of policy makers has been discussed critically. 相似文献
109.
Perceptual hash functions are important for video authentication based on digital signature verifying the originality and integrity of videos. They derive hashes from the perceptual contents of the videos and are robust against the common content-preserving operations on the videos. The advancements in the field of scalable video coding call for efficient hash functions that are also robust against the temporal, spatial and bit rate scalability features of the these coding schemes. This paper presents a new algorithm to extract hashes of scalably coded videos using the 3D discrete wavelet transform. A hash of a video is computed at the group-of-frames level from the spatio-temporal low-pass bands of the wavelet-transformed groups-of-frames. For each group-of-frames, the spatio-temporal low-pass band is divided into perceptual blocks and a hash is derived from the cumulative averages of their averages. Experimental results demonstrate the robustness of the hash function against the scalability features and the common content-preserving operations as well as the sensitivity to the various types of content differences. Two critical properties of the hash function, diffusion and confusion, are also examined. 相似文献
110.
Nabajyoti Saikia 《Fuel》2006,85(2):264-271
Combustion residues generated from different incineration processes create major environmental problems because these materials contain high amounts of toxic substances. In this communication, we report the leaching behaviours of three residues along with their mineralogical compositions. Column leaching experiments at two different pH values were conducted to study the leaching behaviours. Leachants were analyzed to determine the pH, the concentrations of some toxic elements like Pb, Cr, As, Cd, Se, B, Mo and the volume of leachants passing through the columns. Raw and some treated residues were also characterized by XRD and SEM-EPMA techniques. We found that the concentrations of some toxic elements present in the residues as well as in the leachant fractions collected at different time intervals after leaching were very high. The amounts of soluble salts and toxic elements in the municipal solid waste incinerator (MSWI) ash were higher than those in the other two residues. The order of alkalinities of the three residues was: fly ash (FA)>MSWI ash>sewage sludge ash (SS ash). The final pH of the leachant was related to the volume of leachant passing through the column. Some leachant properties were related to the mineralogical compositions of the residues and to the secondary minerals formed during the leaching period. 相似文献