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101.
Moon Jisook; Chen May; Gandhy Shruti U.; Strawderman Myla; Levitsky David A.; Maclean Kenneth N.; Strupp Barbara J. 《Canadian Metallurgical Quarterly》2010,124(3):346
In addition to mental retardation, individuals with Down syndrome (DS) also develop the neuropathological changes typical of Alzheimer's disease (AD) and the majority of these individuals exhibit dementia. The Ts65Dn mouse model of DS exhibits key features of these disorders, including early degeneration of cholinergic basal forebrain (CBF) neurons and impairments in functions dependent on the two CBF projection systems; namely, attention and explicit memory. Herein, we demonstrate that supplementing the maternal diet with excess choline during pregnancy and lactation dramatically improved attentional function of the adult trisomic offspring. Specifically, the adult offspring of choline-supplemented Ts65Dn dams performed significantly better than unsupplemented Ts65Dn mice on a series of 5 visual attention tasks, and in fact, on some tasks did not differ from the normosomic (2N) controls. A second area of dysfunction in the trisomic animals, heightened reactivity to committing an error, was partially normalized by the early choline supplementation. The 2N littermates also benefited from increased maternal choline intake on 1 attention task. These findings collectively suggest that perinatal choline supplementation might significantly lessen cognitive dysfunction in DS and reduce cognitive decline in related neurodegenerative disorders such as AD. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
102.
Gigliola Lusvardi Gianluca Malavasi Ledi Menabue Shruti Shruti 《Materials science & engineering. C, Materials for biological applications》2013,33(6):3190-3196
A gallium containing glass 45.7SiO2·24.1Na2O·26.6CaO·2.6P2O5·1.0Ga2O3 (referred to as “Ga1.0”) and a parent Ga-free glass 46.2SiO2·24.3Na2O·26.9CaO·2.6P2O5 (hereinafter represented as “H”), corresponding to Bioglass® 45S5, were functionalized with Tetraethoxysilane (TEOS) and (3-Aminopropyl)triethoxysilane (APTS) in order to improve their ability to bond with biomolecules, such as drugs, proteins, and peptides. Functionalization with TEOS and APTS promoted the increment in OH groups and formation of NH2 groups on the glass surface, respectively. The presence of OH or NH2 groups was investigated by means of IR spectroscopy and elemental analysis. Moreover, in vitro study of these functionalized glasses was performed in simulated body fluid (SBF) so as to investigate the effect of functionalization on the bioactive behavior of H and Ga1.0. The results showed that the functionalization was obtained along with maintaining their bioactivity. The surfaces of both functionalized glasses were covered by a layer of apatite within 30 days of SBF immersion. In addition, CaCO3 was also identified on the surface of APTS functionalized glasses. However, no gallium release was detected during SBF soaking. 相似文献
103.
Passive, stand-alone, direct methanol fuel cells require a pressure management system that releases CO2 produced in the anode chamber. However, this must be done without allowing the methanol fuel to escape. In this paper, two siloxane membranes are investigated and shown to selectively vent CO2 from the anode chamber. The addition of hydrophobic additives, 1,6-divinylperfluorohexane and 1,9-decadiene, improved the selectivity of the siloxane membranes. The best performing CO2 vent was obtained with 50:50 wt% poly(1-trimethyl silyl propyne) and 1,6-divinylperfluorohexane. 相似文献
104.
Development of angle indexes for soil moisture estimation, dry matter detection and land-cover discrimination 总被引:3,自引:0,他引:3
Shruti Khanna Alicia Palacios-Orueta Michael L. Whiting David Riaño 《Remote sensing of environment》2007,109(2):154-165
A new index was proposed to estimate soil and vegetation moisture based on NIR (858 nm) and SWIR (1240 and 1640 nm) MODIS bands. The Shortwave Angle Slope Index (SASI) parameterizes the general shape of the NIR-SWIR part of the spectrum. We expand on the novel approach used to develop SASI by proposing another index, the Angle at NIR (ANIR). We use laboratory and simulation datasets to validate the ability of SASI to estimate soil and vegetation moisture, and evaluate the advantage for using both SASI and ANIR as land-cover discrimination tools. Our results demonstrate that SASI is a good indicator of soil and vegetation moisture. ANIR shows promise in discriminating dry plant matter from soil and quantifying the amount of dry matter irrespective of changes in soil moisture or green vegetation. When SASI is combined with ANIR, discrimination between soil, dry plant matter, and low to high amounts of green vegetation is significantly improved. Angle indexes are an exciting new way to engineer indexes that contain valuable environmental information not accessible from other indexes. 相似文献
105.
The focus of this work is to study the efficacy of TCP’s flow control algorithm on mobile devices. Specifically, we identify the design limitations of the algorithm when operating in environments, such as smartphones and tablets, where flow control assumes greater importance because of device resource limitations. We then propose an adaptive flow control (AFC) algorithm for TCP that relies not just on the available buffer space but also on the application read-rate at the receiver. We show, using \(NS2\) simulations, that AFC can provide considerable performance benefits over classical TCP flow control. 相似文献
106.
Suravi Chakrabarty Shruti Choudhary Arpit Doshi Fa‐Qiang Liu Rishabh Mohan Manasa P. Ravindra Dhruv Shah Xun Yang Fraser F. Fleming 《Advanced Synthesis \u0026amp; Catalysis》2014,356(10):2135-2196
Isonitriles are delicately poised chemical entities capable of being coaxed to react as nucleophiles or electrophiles. Directing this tunable reactivity with metal and non‐metal catalysts provides rapid access to a large array of complex nitrogenous structures ideally functionalized for medicinal applications. Isonitrile insertion into transition metal complexes has featured in numerous synthetic and mechanistic studies, leading to rapid deployment of isonitriles in numerous catalytic processes, including multicomponent reactions (MCR). Covering the literature from 1990–2014, the present review collates reaction types to highlight reactivity trends and allow catalyst comparison.
107.
M. S. Kaiser P. M. G. Nambissan M. K. Banerjee A. Sachdeva P. K. Pujari 《Journal of Materials Science》2007,42(8):2618-2629
Positron annihilation spectroscopy (PAS), comprising of both positron lifetime and coincidence Doppler broadening measurements,
has been employed for studying the phase decomposition behaviour of scandium doped Al–6Mg alloys. Micro structural and age
hardening studies have also been conducted to substantiate the explanation of the results of PAS. Samples with scandium concentration
ranging from 0 to 0.6 wt.% have been studied. The measured positron lifetimes of undoped alloy reveal that GP zones are absent
in the as-prepared Al–6Mg alloy. The observed positron lifetimes and the results of coincidence Doppler broadening measurements
largely stem from the entrap of positrons at the interface between aluminium rich primary dendrites and the magnesium enriched
interdendritic eutectic mixture of Mg5Al8 (β) and the primary solid solution of aluminium (α). The study also provides evidence of the formation of scandium vacancy
complexes in Al–6Mg alloys doped with scandium upto a concentration of 0.2 wt.%. However such complex formation ceases to
continue beyond 0.2 wt.% Sc; instead, the formation of fine coherent precipitates of Al3Sc is recorded in the as prepared alloy containing 0.6 wt.% scandium. The positron annihilation studies coupled with CDBS
have also corroborated with the fact that the fine coherent precipitates of Al3Sc are formed upon annealing the Al–6Mg alloys doped with scandium of concentration 0.2 wt.% and above. Transmission electron
microscopic studies have provided good evidence of precipitate formation in annealed Al–6Mg–Sc alloys. Elevated temperature
annealing leads to dissociation of the scandium-vacancy complexes, thereby leading to the enhancement of the mobility of magnesium
atoms. This has facilitated fresh nucleation and growth of Mg5Al8 precipitates in the above alloys at 673 K. 相似文献
108.
The post-harvest shelf life of maximum of fruits and vegetables is very limited due to their perishable nature. In India more then 20-25 percent of fruits and vegetables are spoiled before utilization. Despite being the world's second largest producer of fruits and vegetables, in India only 1.5 percent of the total fruits and vegetables produced are processed. Maximum amounts of fruit and vegetable juices turn bitter after extraction due to conversion of chemical compounds. In spite of being under utilized, the utilization of highly nutritive fruits and vegetables is very limited due to high acidity, astringency, bitterness, and some other factors. While improving flavor, palatability, and nutritive and medicinal value of various fruit juices such as aonla, mango, papaya, pineapple, citrus, ber, pear, apple, watermelon, and vegetables including bottle gourd, carrot, beet root, bitter gourd, medicinal plants like aloe vera and spices can also be used for juice blending. All these natural products are valued very highly for their refreshing juice, nutritional value, pleasant flavor, and medicinal properties. Fruits and vegetables are also a rich source of sugars, vitamins, and minerals. However, some fruits and vegetables have an off flavor and bitterness although they are an excellent source of vitamins, enzymes, and minerals. Therefore, blending of two or more fruit and vegetable juices with spices extract for the preparation of nutritive ready-to-serve (RTS), beverages is thought to be a convenient and economic alternative for utilization of these fruits and vegetables. Moreover, one could think of a new product development through blending in the form of a natural health drink, which may also serve as an appetizer. The present review focuses on the blending of fruits, under-utilized fruits, vegetables, medicinal plants, and spices in appropriate proportions for the preparation of natural fruit and vegetable based nutritive beverages. 相似文献
109.
Manju Arora Anupama Sachdeva Vandna Luthra R. P. Tandon R. P. Pant 《Integrated ferroelectrics》2013,141(1):144-151
Nanocrystalline PLZT thin films of composition Pb1-xLaxZr0.52Ti0.48 (x = 0, 2, 5%) were deposited on silicon substrates by sol-gel process using lead acetate trihydrate, lanthanum nitrate hydrate, zirconium propoxide and titanium propoxide as lead, lanthanum, zirconium and titanium precursor materials. Experimental studies have been made on solitary waves in 2 mol% lanthanum doped sol-gel derived lead zirconate titanate thin films. The solitary waves are generated under the influence of external alternating electric field, which has the same frequency as the external field. These solitary waves propagate through the thin film upto its boundary and then reflect back. The magnitude of the solitary waves attenuates as they move away from the electrodes and their phase reverses on reflection. For certain frequencies of the external electric field, solitary waves exhibit resonance effect. Distortion in hysteresis loops has been demonstrated on the basis of solitary waves propagation in the film having different electrode area. 相似文献
110.