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1.
Some reports demonstrated successful genome editing in pigs by one-step zygote microinjection of mRNA of CRISPR/Cas9-related components. Given the relatively long gestation periods and the high cost of housing, the establishment of a single blastocyst-based assay for rapid optimization of the above system is required. As a proof-of-concept, we attempted to disrupt a gene (GGTA1) encoding the α-1,3-galactosyltransferase that synthesizes the α-Gal epitope using parthenogenetically activated porcine oocytes. The lack of α-Gal epitope expression can be monitored by staining with fluorescently labeled isolectin BS-I-B4 (IB4), which binds specifically to the α-Gal epitope. When oocytes were injected with guide RNA specific to GGTA1 together with enhanced green fluorescent protein (EGFP) and human Cas9 mRNAs, 65% (24/37) of the developing blastocysts exhibited green fluorescence, although almost all (96%, 23/24) showed a mosaic fluorescent pattern. Staining with IB4 revealed that the green fluorescent area often had a reduced binding activity to IB4. Of the 16 samples tested, six (five fluorescent and one non-fluorescent blastocysts) had indel mutations, suggesting a correlation between EGFP expression and mutation induction. Furthermore, it is suggested that zygote microinjection of mRNAs might lead to the production of piglets with cells harboring various mutation types.  相似文献   
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Liquid marble (LM) is a droplet that is wrapped by hydrophobic solid particles, which behave as a non-wetting soft solid. Based on these properties, LM can be applied in fluidics and soft device applications. A wide variety of functional particles have been synthesized to form functional LMs. However, the formation of multifunctional LMs by integrating several types of functional particles is challenging. Here, a general strategy for the flexible patterning of functional particles on droplet surfaces in a patchwork-like design is reported. It is shown that LMs can switch their macroscopic behavior between a stable and active state on super-repellent surfaces in situ by jamming/unjamming the surface particles. Active LMs hydrostatically coalesce to form a self-sorted particle pattern on the droplet surface. With the support of LM handling robotics, on-demand cyclic activation–manipulation–coalescence–stabilization protocols by LMs with different sizes and particle types result in the reliable design of multi-faced LMs. Based on this concept, a single bi-functional LM is designed from two mono-functional LMs as an advanced droplet carrier.  相似文献   
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This paper describes the high performance of T-shaped-gate CMOS devices with effective channel lengths in the sub-0.1-μm region. These devices were fabricated by using selective W growth, which allows low-resistance gates smaller than 0.1 μm to be made without requiring fine lithography alignment. We used counter-doping to scale down the threshold voltage while still maintaining acceptable short-channel effects. This approach allowed us to make ring oscillators with a gate-delay time as short as 21 ps at 2 V with a gate length of 0.15 μm. Furthermore, we experimentally show that the high circuit speed of a sub-0.1-μm gate length CMOS device is mainly due to the PMOS device performance, especially in terms of its drivability  相似文献   
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By using the fluorescent calcium indicator fura-2, it was found that the concentration of free Ca2+ in the cytoplasm of Trypanosoma cruzi trypomastigotes incubated in the presence or absence of external calcium was maintained at very low levels (10-20 nM). When trypomastigotes were incubated in the presence of succinate and ATP and permeabilized with digitonin, they lowered the medium calcium concentration to a submicromolar level. In the presence of 1 microM FCCP the initial rate of Ca2+ sequestration by these permeabilized cells was very slow. When succinate alone was present, the initial rate of Ca2+ accumulation was slower than with ATP plus succinate, and the calcium set point was about 0.6 microM. The succinate dependence and FCCP sensitivity of the later Ca2+ uptake indicate that it may be exerted by the mitochondria. High concentrations of the tumor promoter thapsigargin slightly increased cytosolic Ca2+ in the presence of extracellular Ca2+ but had no effect on the FCCP- and oligomycin/antimycin A-insensitive Ca2+ pool. In addition, when used at those concentrations (4-20 microM), thapsigargin was shown to release Ca2+ from the mitochondria and to decrease the inner mitochondrial membrane potential of trypomastigotes and epimastigotes as measured using safranine O. Despite the presence of inositol phosphates as determined by [3H]inositol incorporation, no IP3-sensitive Ca2+ release could be detected in trypomastigotes.  相似文献   
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Oda  Yayoi  Abe  Tsuneyuki  Takano  Ruriko  Tatsuta  Amane  Nakamura  Minoru 《Behaviormetrika》2007,34(1):45-57

By using structural equations, we investigated the effect of chronic stress on salivary cortisol rhythm and proposed a causal model of chronic stress by using psychosocial and physiological data. First, 111 healthy workers (48 males, 63 females) completed questionnaires on chronic stress and lifestyle habits. Then, they provided saliva samples and answered questionnaires that were prepared to assess their psychological states 5 times (on waking up and at 10:00, 11:40, 14:00, and 16:00) on workdays. Structural equation modeling (SEM) revealed that chronic stress and longer commuting time resulted in sleep irregularities and this disrupted the cortisol circadian rhythm. This suggests that chronic stress disrupts the cortisol circadian rhythm even in healthy individuals, and sleep regularity mediates the effect of chronic stress on the cortisol rhythm.

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Automated camerawork for capturing desktop presentations   总被引:1,自引:0,他引:1  
A novel automated camera control method for capturing desktop presentations is introduced. Typical features and the camerawork of shots that appear frequently in TV programs are discussed. To realise those features in this automated video capturing system, the purpose of camerawork is classified from two points of view: target and aspect-of-target. Then, the correspondence between the classification and typical shots and camerawork is considered. A virtual-frame control algorithm based on this idea is proposed, and its implementation in a video production system. Results are shown that verify this method through two kinds of experiments, virtual video capturing using CG animations and real video capturing of real presentations.  相似文献   
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To investigate the molecular basis of altered expression of the H-cadherin gene, we used polymerase chain reaction-single strand conformation polymorphism and DNA sequencing to examine the H-cadherin gene in 48 primary breast cancers in which loss of the long arm of chromosome 16 had been detected. We identified no mutations other than somatic 5-bp deletion within the coding region in a single tumor. The very low frequency of mutation found in these experiments suggests that H-cadherin is usually not a primary target for carcinogenesis in human breast cancers, and that reduction of its expression is likely to be a consequence of some other genetic event(s).  相似文献   
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