Electrical activation of optical transitions to parity-forbidden dark excitonic states in individual carbon nanotubes is reported. We examine electric-field effects on various excitonic states by ...simultaneously measuring photocurrent and photoluminescence. As the applied field increases, we observe an emergence of new absorption peaks in the excitation spectra. From the diameter dependence of the energy separation between the new peaks and the ground state of E 11 excitons, we attribute the peaks to the dark excited states which became optically active due to the applied field. Field-induced exciton dissociation can explain the photocurrent threshold field, and the edge of the E 11 continuum states has been identified by extrapolating to zero threshold.
This phase I study was designed to examine the maximum tolerated dose (MTD), the dose-limiting toxicities (DLTs), the recommended dose (RD) for phase II, and the pharmacokinetics of NK105, a new ...polymeric micelle carrier system for paclitaxel (PTX). NK105 was administered as a 1-h intravenous infusion every 3 weeks, without antiallergic premedication. The starting dose was 10 mg m(-2), and the dose was escalated according to the accelerated titration method. Nineteen patients were recruited. The tumour types treated included pancreatic (n=11), bile duct (n=5), gastric (n=2), and colonic (n=1) cancers. Neutropenia was the most common haematological toxicity. A grade 3 fever developed in one patient given 180 mg m(-2). No other grades 3 or 4 nonhaematological toxicities, including neuropathy, was observed during the entire study period. DLTs occurred in two patients given 180 mg m(-2) (grade 4 neutropenia lasting for more than 5 days). Thus, this dose was designated as the MTD. Grade 2 hypersensitivity reactions developed in only one patient given 180 mg m(-2). A partial response was observed in one patient with pancreatic cancer. The maximum concentration (C(max)) and area under the concentration (AUC) of NK105 were dose dependent. The plasma AUC of NK105 at 150 mg m(-2) was approximately 15-fold higher than that of the conventional PTX formulation. NK105 was well tolerated, and the RD for the phase II study was determined to be 150 mg m(-2) every 3 weeks. The results of this phase I study warrant further clinical evaluation.
Vernalization, the requirement of a long exposure to low temperatures to induce flowering, is an essential adaptation of plants to cold winters. We have shown recently that the vernalization gene ...VRN-1 from diploid wheat Triticum monococcum is the meristem identity gene APETALA1, and that deletions in its promoter were associated with spring growth habit. In this study, we characterized the allelic variation at the VRN-1 promoter region in polyploid wheat. The Vrn-A1a allele has a duplication including the promoter region. Each copy has similar foldback elements inserted at the same location and is flanked by identical host direct duplications (HDD). This allele was found in more than half of the hexaploid varieties but not among the tetraploid lines analyzed here. The Vrn-A1b allele has two mutations in the HDD region and a 20-bp deletion in the 5' UTR compared with the winter allele. The Vrn-A1b allele was found in both tetraploid and hexaploid accessions but at a relatively low frequency. Among the tetraploid wheat accessions, we found two additional alleles with 32 bp and 54 bp deletions that included the HDD region. We found no size polymorphisms in the promoter region among the winter wheat varieties. The dominant Vrn-A1 allele from two spring varieties from Afghanistan and Egypt (Vrn-A1c allele) and all the dominant Vrn-B1 and Vrn-D1 alleles included in this study showed no differences from their respective recessive alleles in promoter sequences. Based on these results, we concluded that the VRN-1 genes should have additional regulatory sites outside the promoter region studied here.
Abstract Introduction The velocities of the lateral shear waves (Vs; m s−1 ) generated by an acoustic radiation force impulse (ARFI) correlate with Young's modulus. Therefore, ARFI can be used as a ...new method to evaluate tissue elasticity. The aim of this study was to investigate the safety of ARFI imaging and the differences in placental elasticity in complicated cases. Methods The study population included 115 patients between 26 and 41 weeks gestation, who were divided into three groups, namely normal, fetal growth restriction (FGR) and pregnancy-induced hypertension (PIH). After delivery, the Vs values of the placenta were measured ex vivo . After ARFI imaging, microscopic examination was performed, the Vs values were compared among the three groups and the relationship between the Vs values and neonatal birthweight Z -score was investigated. Results No histological changes were noted even after ARFI imaging. The Vs values in the FGR group were significantly higher than those in the normal group (1.94 ± 0.74 and 1.31 ± 0.35 m s−1 , respectively; p < 0.05). The Vs values demonstrated a significant negative correlation with the Z -score. Moreover, as the Z -score became lower, the Vs values became higher in the range of Z -scores under −0.5 standard deviation (SD). Discussion We speculate that the increased Vs values in the FGR group may have been caused by histological changes, and that a more severe FGR might result in increased Vs values. Conclusion ARFI imaging was observed to have no apparent histological damage to the placental tissue. Ex vivo placentas from the FGR group were significantly more firm. Moreover, Vs values and Z -scores of birthweight had a significant negative correlation. Additional investigations are needed about the utility of this method for the evaluation of placental function in vivo.
The two main trends in the progress of ultrawide-band/high-frequency photodetectors (PD's), improving the bandwidth-efficiency product and obtaining a high saturation current, are reviewed. With ...respect to achieving large bandwidth-efficiency, the limiting factors and potentials of edge-coupled (waveguide, waveguide-fed, traveling-wave, periodic-traveling-wave), resonant-cavity, and refracting-facet photodiodes, as well as the avalanche photodiode are discussed. Regarding high-saturation current, the author estimated how much the space-charge effect limits the saturation current and two ways to reduce the space-charge effect are outlined. One way is to distribute the photocarriers along the edge-coupled PD's and the other is to increase the carrier velocity using a uni-traveling carrier structure. The waveguide-photodiode-based technologies that we have developed are also presented; namely the design and fabrication of a 100-GHz waveguide photodiode (WGPD), uni-traveling carrier WGPD, 60-GHz packaging, and a 20-GHz large-core WGPD for planar lightwave circuit integration. A 50-Gb/s receiver opto-electronic integrated circuit technology based on the WGPD is also presented.
RECK is a novel tumour suppressor gene that negatively regulates matrix metalloproteinases (MMPs) and inhibits tumour invasion, angiogenesis and metastasis. In the present study, we investigated the ...effects of epigallocatechin-3-gallate (EGCG), a major polyphenol in green tea, on the methylation status of the RECK gene and cancer invasion in oral squamous cell carcinoma cell lines. Our results showed that treatment of oral cancer cells with EGCG partially reversed the hypermethylation status of the RECK gene and significantly enhanced the expression level of RECK mRNA. Inhibition of MMP-2 and MMP-9 levels was also observed in these cells after treatment with EGCG. Interestingly, EGCG significantly suppressed cancer cell-invasive ability by decreasing the number of invasive foci (P<0.0001) as well as invasion depth (P<0.005) in three-dimensional collagen invasion model. Although further investigation is required to assess the extent of contribution of RECK on MMPs to the suppression of invasive behaviour, these results support the conclusion that EGCG plays a key role in suppressing cell invasion through multiple mechanisms, possibly by demethylation effect on MMP inhibitors such as RECK.
Increasing accuracy of the theory and experiment of the n=2 ^{3}P fine structure of helium has allowed for increasingly precise tests of quantum electrodynamics (QED), determinations of the ...fine-structure constant α, and limitations on possible beyond the standard model physics. Here we present a 2 ppb measurement of the J=1 to J=0 interval. The measurement is performed using frequency-offset separated-oscillatory fields. Our result of 29 616 955 018(60) Hz represents a landmark for helium fine-structure measurements, and, for the first time, will allow for a 1-ppb determination of the fine-structure constant when QED theory for the interval is improved.
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