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61.
62.
Within the visual system, docosahexaenoic acid (DHA, 22:6n−3) is an important structural component for retinal photoreceptors and cortical gray matter. There is a marked decrease in
neural DHA accumulation in the face of DHA deficiency. DHA is accumulated at an accelerated rate during pregnancy, especially
in the third trimester. However, pregnant women in the US and Canada have dietary DHA intakes that are significantly below
the optimal level. The main objective of this study was to determine whether a DHA-functional food during pregnancy would
benefit infant visual acuity at four and six months of age measured behaviorally using the acuity card procedure (ACP). In
a randomized, longitudinal, double-blinded, and placebo-controlled trial, 30 pregnant women received either the DHA-functional
food (n = 16) or the placebo (n = 14). There were significant main effects for visual acuity at four months of age (P = 0.018). The mean acuity scores were 3.8 ± 1.1 cycles/degree in the DHA group versus 3.2 ± 0.7 cycles/degree in the placebo
group. At six months there were no group differences. Based on our results, we conclude that DHA supplemented during pregnancy
plays a role in the maturation of the visual system. 相似文献
63.
The optimal allocation of resources at the firm level to transform emergent technological invention into commercially successful products depends on the effective assessment and selection of projects. This study develops a multidisciplinary model for differentiating, prioritizing, and selecting investment in technological projects within an organization’s portfolio. Approaches from project portfolio and strategic technology management are integrated to explore how a particular product within a diverse project portfolio may be prioritized and developed. Our results suggest that the application of the suggested model to a portfolio of biotechnology projects may enhance the assessment of internal capabilities and external competitiveness, thereby providing a basis for firms to prioritize and preferentially allocate scarce resources within a portfolio of heterogeneous technologies. 相似文献
64.
Sayan Bhattacharyya Ilana Perelshtein Ofer Moshe Daniel H. Rich Aharon Gedanken 《Advanced functional materials》2008,18(11):1641-1653
The carbon‐encapsulated, Mn‐doped ZnSe (Zn1−xMnxSe@C) nanowires, nanorods, and nanoparticles are synthesized by the solvent‐free, one‐step RAPET (reactions under autogenic pressure at elevated temperature) approach. The aspect ratio of the nanowires/nanorods is altered according to the Mn/Zn atomic ratio, with the maximum being observed for Mn/Zn = 1:20. A 10–20 nm amorphous carbon shell is evidenced from electron microscopy analysis. The replacement of Zn by Mn in the Zn1−xMnxSe lattice is confirmed by the hyperfine splitting values in the electron paramagnetic resonance (EPR) experiments. Raman experiments reveal that the Zn1−xMnxSe core is highly crystalline, while the shell consists of disordered graphitic carbon. Variable‐temperature cathodoluminescence measurements are performed for all samples and show distinct ZnSe near‐band‐edge and Mn‐related emissions. An intense and broad Mn‐related emission at the largest Mn alloy composition of 19.9% is further consistent with an efficient incorporation of Mn within the host ZnSe lattice. The formation of the core/shell nanowires and nanorods in the absence of any template or structure‐directing agent is controlled kinetically by the Zn1−xMnxSe nucleus formation and subsequent carbon encapsulation. Mn replaces Zn mainly in the (111) plane and catalyzes the nanowire growth in the [111] direction. 相似文献
65.
The notion of bilattice was introduced by Ginsberg, and further examined by Fitting, as a general framework for many applications. In the present paper we develop proof systems, which correspond to bilattices in an essential way. For this goal we introduce the notion of logical bilattices. We also show how they can be used for efficient inferences from possibly inconsistent data. For this we incorporate certain ideas of Kifer and Lozinskii, which happen to suit well the context of our work. The outcome are paraconsistent logics with a lot of desirable properties. A preliminary version of this paper appears in Arieli and Avron (1994). 相似文献
66.
Pollard HB Srivastava M Eidelman O Jozwik C Rothwell SW Mueller GP Jacobowitz DM Darling T Guggino WB Wright J Zeitlin PL Paweletz CP 《Proteomics. Clinical applications》2007,1(9):934-952
Proteomics for clinical applications is presently in a state of transition. It has become clear that the classical approaches based on 2-DE and/or MS need to be complemented by different kinds of technologies. The well-known problems include sample complexity, sensitivity, quantitation, reproducibility, and analysis time. We suggest that the new technologies for clinical proteomics can be supported by antibody-centric protein microarray platforms. These platforms presently include antibody microarrays and lysate, or reverse capture/reverse phase protein microarrays. Other forms of these arrays are in less mature developmental stages, including ORF and self assembling protein microarrays. Bioinformatic support for interpreting these arrays is becoming more available as the whole field of systems biology begins to mature. The present set of applications for these platforms is profoundly focused on certain common cancers, immunology, and cystic fibrosis. However, we predict that many more disease entities will become studied as knowledge of the power and availability of these platforms becomes more widely established. We anticipate that these platforms will eventually evolve to accommodate label-free detection technologies, human genome-scale numbers of analytes, and increases in analytic and bioinformatic speeds. 相似文献
67.
68.
Given an LTL formula φ in negation normal form, it can be strengthened by replacing some of its literals with false. Given such a formula and a model M that satisfies it, vacuity and mutual vacuity attempt to find one or a maximal set of literals, respectively, with which φ can be strengthened while still being satisfied by M. We study the problem of finding the strongest LTL formula that satisfies M and is in the Boolean closure of strengthened versions of φ as defined above. This formula is stronger or equally strong to any formula that can be obtained by vacuity and mutual vacuity. We present our algorithms in the framework of lattice automata. 相似文献
69.
An Huang Haodong Liu Ofer Manor Ping Liu James Friend 《Advanced materials (Deerfield Beach, Fla.)》2020,32(14):1907516
Both powerful and unstable, practical lithium metal batteries have remained a difficult challenge for over 50 years. With severe ion depletion gradients in the electrolyte during charging, they rapidly develop porosity, dendrites, and dead Li that cause poor performance and, all too often, spectacular failure. Remarkably, incorporating a small, 100 MHz surface acoustic wave device (SAW) solves this problem. Providing acoustic streaming electrolyte flow during charging, the device enables dense Li plating and avoids porosity and dendrites. SAW-integrated Li cells can operate up to 6 mA cm−2 in a commercial carbonate-based electrolyte; omitting the SAW leads to short circuiting at 2 mA cm−2. The Li deposition is morphologically dendrite-free and close to theoretical density when cycling with the SAW. With a 245 µm thick Li anode in a full Li||LFP (LiFePO4) cell, introducing the SAW increases the uncycled Li from 145 to 225 µm, decreasing Li consumption from 41% to only 8%. A closed-form model is provided to explain the phenomena and serve as a design tool for integrating this chemistry-agnostic approach into batteries whatever the chemistry within. 相似文献
70.
Inspired by Hoare’s rule for recursive procedures, we present three proof rules for the equivalence between recursive programs. The first rule can be used for proving partial equivalence of programs; the second can be used for proving their mutual termination; the third rule can be used for proving the equivalence of reactive programs. There are various applications to such rules, such as proving equivalence of programs after refactoring and proving backward compatibility. 相似文献