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81.
Xinghao Hu Byeonghwa Lim Sri Ramulu Torati Junjia Ding Valentine Novosad Mi‐Young Im Venu Reddy Kunwoo Kim Eunjoo Jung Asif Iqbal Shawl Eunjoo Kim CheolGi Kim 《Small (Weinheim an der Bergstrasse, Germany)》2018,14(25)
The precise delivery of biofunctionalized matters is of great interest from the fundamental and applied viewpoints. In spite of significant progress achieved during the last decade, a parallel and automated isolation and manipulation of rare analyte, and their simultaneous on‐chip separation and trapping, still remain challenging. Here, a universal micromagnet junction for self‐navigating gates of microrobotic particles to deliver the biomolecules to specific sites using a remote magnetic field is described. In the proposed concept, the nonmagnetic gap between the lithographically defined donor and acceptor micromagnets creates a crucial energy barrier to restrict particle gating. It is shown that by carefully designing the geometry of the junctions, it becomes possible to deliver multiple protein‐functionalized carriers in high resolution, as well as MCF‐7 and THP‐1 cells from the mixture, with high fidelity and trap them in individual apartments. Integration of such junctions with magnetophoretic circuitry elements could lead to novel platforms without retrieving for the synchronous digital manipulation of particles/biomolecules in microfluidic multiplex arrays for next‐generation biochips. 相似文献
82.
Tejaswi Thunugunta Aswath Channa Reddy Shivashankara Kodthalu Seetharamaiah Laxman Ramanna Hunashikatti Satisha Gowdra Chandrappa Narayana Cherukatu Kalathil Lakshmana Reddy Dhoranapalli Chinnappa Reddy 《IET nanobiotechnology / IET》2018,12(6):706
The increasing use of nanoparticles and their occurrence in the environment has made it imperative to elucidate their impact on the environment. Although several studies have advanced the authors’ understanding of nanoparticle–plant interactions, their knowledge of the exposure of plants to nanoparticles and their effects on edible crop plants remain meager and is often paradoxical. The aim of this study was to increase their knowledge on the effect of zinc oxide (ZnO) nanoparticles on eggplant seed germination and seedling growth. ZnO nanoparticles had a negative effect on the growth of eggplant in plant tissue‐culture conditions, as the growth of seedlings decreased with the increase in the concentration of ZnO nanoparticles. In contrast, ZnO nanoparticles enhanced eggplant growth under greenhouse conditions. The accumulation of ZnO nanoparticles in various parts of eggplant was observed through scanning electron microscopy of both plant tissue‐culture and greenhouse‐raised eggplant seedlings. To the best of their knowledge, this is the first study to report on ZnO nanoparticle accumulation in eggplant and its effect on seed germination and seedling growth.Inspec keywords: crops, zinc compounds, scanning electron microscopy, II‐VI semiconductors, nanoparticles, agriculture, cellular biophysics, nanofabricationOther keywords: plant tissue‐culture, greenhouse‐raised eggplant seedlings, ZnO nanoparticle accumulation, seedling growth, ZnO nanoparticles, nanoparticle–plant interactions, zinc oxide nanoparticles, eggplant seed germination, eggplant growth, ZnO 相似文献
83.
Hongche Liu Tsai-Hong Hong Martin Herman Ted Camus Rama Chellappa 《Computer Vision and Image Understanding》1998,72(3):271-286
There have been two thrusts in the development of optical flow algorithms. One has emphasized higher accuracy; the other faster implementation. These two thrusts, however, have been independently pursued, without addressing the accuracy vs efficiency trade-offs. Although the accuracy–efficiency characteristic is algorithm dependent, an understanding of a general pattern is crucial in evaluating an algorithm as far as real-world tasks are concerned, which often pose various performance requirements. This paper addresses many implementation issues that have often been neglected in previous research, including temporal filtering of the output stream, algorithms' flexibility, and robustness to noise, subsampling, etc. Their impacts on accuracy and/or efficiency are emphasized. We present a survey of different approaches toward the goal of higher performance and present experimental studies on accuracy vs efficiency trade-offs. A detailed analysis of how this trade-off affects algorithm design is manifested in a case study involving two state-of-the-art optical flow algorithms: a gradient and a correlation-based method. The goal of this paper is to bridge the gap between the accuracy- and the efficiency-oriented approaches. 相似文献
84.
ED Cox H Diaz-Arauzo Q Huang MS Reddy C Ma B Harris R McKernan P Skolnick JM Cook 《Canadian Metallurgical Quarterly》1998,41(14):2537-2552
A pharmacophore and an alignment rule have previously been reported for BzR agonist ligands. The design and synthesis of 6-(propyloxy)-4-(methoxymethyl)-beta-carboline-3-carboxylic acid ethyl ester (6-PBC, 24, IC50 = 8.1 nM) was based on this pharmacophore. When evaluated in vivo this ligand exhibited anticonvulsant/anxiolytic activity but was devoid of the muscle relaxant/ataxic effects of "classical" 1,4-benzodiazepines (i.e., diazepam). Significantly, 6-PBC 24 also reversed diazepam-induced muscle relaxation in mice. The 3-substituted analogues 40-46 and 48 of 6-PBC 24 and Zk 93423 27(IC50 = 1 nM) were synthesized and evaluated in vitro to determine what affect these modifications would have on the binding affinity at recombinant BzR subtypes. With the exception of the 3-amino ligands 40 and 41, all the beta-carbolines were found to exhibit high binding affinity at BzR sites. The 3-propyl ether derivative 45 was also evaluated in vivo and found to be devoid of any proconvulsant or anticonvulsant activity at doses up to 40 mg/kg. The 6-(1-naphthylmethyloxy) and 6-octyloxy analogues 25, 26, 28, and 29 of 6-PBC 24 were synthesized to further evaluate the proposed alignment of agonists vs inverse agonists in the pharmacophore of the BzR. In addition, ligands 26 and 29 were designed to probe the dimensions of lipophilic pocket L3 at the agonist site. The activity of 29 was evaluated in vivo; however, this analogue elicited no pharmacological effects at doses up to 80 mg/kg. These and other related beta-carbolines were also examined in five recombinant GABAA receptor subtypes. Ligands 52-61 all exhibited moderate to high affinity at GABAA receptors containing alpha1 subunits. These ligands will be useful in further defining the pharmacophore at alpha1 beta3 gamma2 receptors. 相似文献
85.
The re-evaluation of previous and existing methods in materials processing is becoming ever more critical because of processing and starting materials cost factors. A study on the synthesis and properties investigation of hypereutectic Al–13.5Si–2.5Mg alloy reinforced with carbon chars using coconut shell as the organic precursor has been carried out. The low-cost, double compaction solid-state technique was used. Reinforcing the hypereutectic alloy with coconut shell char particles (size:<140 m) at 2 vol % and consolidating by reaction sintering at 600 °C in vacuum for 15 min, followed by near net-shape compaction at 250 MPa, increased the hardness of the alloy 6% while reducing its strength (UTS) by only 3%. The use of palm kernel shell char as the dispersed phase was found to yield identical results. At 2 vol % char, the mechanical properties, sintered density and dimensional changes were optimally found to be suitable for lightweight anti-friction electromechanical applications. Attempts to reinforce the alloy with 2 vol % coconut shell chars activated in CO2 reduced its strength in the range of 19 to 26% at different burn-off percentages. This is attributed to the higher amount of oxide products formed during the activation process. At 600 °C, formation of the brittle Al4C3 phase in the different sintered composites containing activated and unactivated chars was identified by X-ray studies. © 1998 Chapman & Hall 相似文献
86.
R. Venugopal R. P. Vijayalakshmi D. R. Reddy B. K. Reddy 《Journal of Materials Science》1996,31(15):4081-4085
Thin films of ZnSe
x
CdS1–x (t 0.6 m) over the entire range of x, were deposited on glass substrates at two temperatures, T
s (350 and 470 K) by vacuum evaporation. X-ray diffraction studies showed that all the films were polycrystalline in nature. Films prepared at 470 K were nearly stoichiometric. Grain size increased with substrate temperature, T
s. The electrical conductivity and Hall measurements were carried out by d.c. van der Pauw technique. Hall effect studies/hot probe test showed that all the films were of n-type conductivity. Hall mobility increased with T
s. In addition, mobilities increased with temperature in films of all compositions, indicating the dominance of grain-boundary scattering. Grain-boundary potentials were in range 0.03–0.06 eV. 相似文献
87.
DY Graham R Genta DG Evans R Reddy JE Clarridge CA Olson AL Edmonds N Siepman 《Canadian Metallurgical Quarterly》1996,91(10):2120-2124
BACKGROUND: Omeprazole is known to have an effect on Helicobacter pylori in vivo. One opinion is that H. pylori "migrates" from the antrum to the corpus in response to omeprazole therapy. METHODS: To determine whether H. pylori migrates in response to omeprazole, we assessed the presence of H. pylori in the antrum and corpus in duodenal ulcer patients receiving omeprazole for 4 wk. Culture and histological examination of antral biopsies (Genta stain) were performed before patients received omeprazole, at the end of therapy, and 4-6 wk later. The end points were presence or absence of H. pylori and the number of H. pylori colonies per biopsy. RESULTS: Seventy-two patients had H. pylori in both the antrum and corpus at entry and 4-6 wk after ending therapy. Three general patterns were prevalent at the end of omeprazole therapy: antrum- and corpus-positive (54%), antrum-negative and corpus-positive (24%), both antrum- and corpus-negative (21%), and one patient had antrum-positive with corpus-negative (1%). Evaluation of the number of colonies per biopsy in those who remained H. pylori-positive in both the antrum and corpus throughout showed that the number of H. pylori decreased in both the antrum and corpus during therapy (507 +/- 60 vs. 225 +/- 51, p < 0.01 and 415 +/- 58 vs. 290 +/- 46 0.1) for antrum and corpus, respectively, and tended to return to pre-therapy levels 4-6 wk later. The number of H. pylori in the corpus also decreased in the antrum-negative and corpus-positive group during therapy with omeprazole (433 +/- 87 vs. 185 +/- 61, p < 0.05). In most of the patients studied, the number of H. pylori in the corpus was less posttreatment than it was pretreatment. The decrease in H. pylori load was also reflected in the development of false-negative urea breath tests. CONCLUSIONS: Omeprazole is detrimental to H. pylori in both the antrum and the corpus; migration from the antrum to the corpus in response to omeprazole is a myth. 相似文献
88.
In last years, Face recognition based on 3D techniques is an emergent technology which has demonstrated better results than
conventional 2D approaches. Using texture (180° multi-view image) and depth maps is supposed to increase the robustness towards
the two main challenges in Face Recognition: Pose and illumination. Nevertheless, 3D data should be acquired under highly
controlled conditions and in most cases depends on the collaboration of the subject to be recognized. Thus, in applications
such as surveillance or control access points, this kind of 3D data may not be available during the recognition process. This
leads to a new paradigm using some mixed 2D-3D face recognition systems where 3D data is used in the training but either 2D
or 3D information can be used in the recognition depending on the scenario. Following this concept, where only part of the
information (partial concept) is used in the recognition, a novel method is presented in this work. This has been called Partial
Principal Component Analysis (P2CA) since they fuse the Partial concept with the fundamentals of the well known PCA algorithm. This strategy has been proven
to be very robust in pose variation scenarios showing that the 3D training process retains all the spatial information of
the face while the 2D picture effectively recovers the face information from the available data. Furthermore, in this work,
a novel approach for the automatic creation of 180° aligned cylindrical projected face images using nine different views is
presented. These face images are created by using a cylindrical approximation for the real object surface. The alignment is
done by applying first a global 2D affine transformation of the image, and afterward a local transformation of the desired
face features using a triangle mesh. This local alignment allows a closer look to the feature properties and not the differences.
Finally, these aligned face images are used for training a pose invariant face recognition approach (P2CA). 相似文献
89.
Considerable research has been done on using information from multiple modalities, like hands, facial gestures or speech, for better interaction between humans and computers, and many promising human–computer interfaces (HCI) have been developed in recent years. However, most of the current HCI systems have a few drawbacks: firstly, they are highly dependent on the performance of individual sensors. S econdly, the information fusion process from these sensors tends to ignore the semantic nature of the modalities, which may reinforce or clarify each other over time. Finally, they are not robust enough at representing the imprecise nature of human gestures, since individual gestures are highly ambiguous in themselves. In this paper, we propose an approach for the semantic fusion of different input modalities, based on transferable belief models. We show that this approach allows for a better representation of the ambiguity involved in recognizing gestures. Ambiguity is resolved by combining the beliefs of the individual sensors on the input information, to form new extended concepts, based on a pre-defined domain specific knowledge base, represented by conceptual graphs. We apply this technique to a multimodal system consisting of a hand gesture recognition sensor and a brain computing interface. It is shown that the technique can successfully combine individual gestures obtained from the two sensors, to form meaningful concepts and resolve ambiguity. The advantage of this approach is that it is robust even if one of the sensors is inefficient or has no input. Another important feature is its scalability, wherein more input modalities, like speech or facial gestures, can be easily integrated into the system at minimal cost, to form a comprehensive HCI interface. 相似文献
90.