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61.
Advances in molecular imaging modalities have accelerated the diagnosis and treatment of human diseases. However, tumors less than 1 cm in size still remain difficult to localize by conventional means because of the difficulty in specific targeting/delivery to the tumor site. Furthermore, high nonspecific uptake in the major organs and persistent background retention results in low tumor-to-background ratio. The targeting and therapy of gastrointestinal stromal tumors (GIST) using nonsticky and renal clearable theranostic nanoparticles (a.k.a. H-Dots) are demonstrated. H-Dots not only target GIST for image-guided surgery, but also tailor the fate of anticancer drugs such as imatinib (IM) to the tumor site resulting in efficient treatment of unresectable GIST. In addition, H-Dots can monitor targetability, pharmacokinetics, and drug delivery, while also showing therapeutic efficacy in GIST-bearing xenograft mice following surgical resection. More importantly, IM loaded H-Dots exhibit lower uptake into the immune system, improved tumor selectivity, and increased tumor suppression compared to free IM, which accumulates in the spleen/liver. Precisely designed H-Dots can be used as a promising theranostic nanoplatform that can potentially reduce the side effects of conventional chemotherapies.  相似文献   
62.
Multimedia Tools and Applications - We developed a robust ball-position-measurement system that can be used for actual football games. It measures the positions of a ball by integrating tracking...  相似文献   
63.
Multiple melting behavior of poly(butylene-2,6-naphthalate) (PBN) was studied with X-ray analysis and differential scanning calorimetry (DSC). Double endothermic peaks L and H attributed to the α-form crystal modification, a small peak attributed to the β-form crystal modification, and a new shoulder peak S at a lower temperature of peak H appeared in the DSC melting curves. Wide-angle X-ray diffraction patterns of the samples isothermally crystallized at 200 and 220 °C were obtained at a heating rate of 1 K min−1, successively. In this heating process, change of crystal structure and increase of quantity of the β-form crystallites could not be observed up to the final melting. With increasing temperature, the diffraction intensity decreased gradually and then increased distinctly before a steep decrease due to the final melting. The X-ray analysis clearly proved the melt-recrystallization during heating. The β-form crystal modification was formed during slow heating process in the high temperature region.  相似文献   
64.
Nanostructuring is known to be an effective method to improve thermoelectric performance but, generally, it requires complex procedures and much labor. In the present study, self-assembled nanometer-sized composite structures of silicon (Si) and chromium disilicide (CrSi2) were easily fabricated by the rapid solidification of a melt with a eutectic composition. Ribbon-like samples were obtained with a dominant nanostructure of fine aligned lamellae with a spacing range of 20–35 nm. The thermoelectric power factor of the ribbon was observed to be 1.2 mW/mK2 at room temperature and reached 3.0 mW/mK2 at 773 K. The thermal conductivity was 65% lower than that of a bulk eutectic sample. The results suggest that this method is promising for fabricating an effective nanostructure for thermoelectric performance.  相似文献   
65.
The Mycobacterium tuberculosis Ser/Thr kinase PknB is implicated in the regulation of bacterial cell growth and cell division. The intracellular kinase function of PknB is thought to be triggered by peptidoglycan (PGN) fragments that are recognized by the extracytoplasmic domain of PknB. The PGN in the cell wall of M. tuberculosis has several unusual modifications, including the presence of N-glycolyl groups (in addition to N-acetyl groups) in the muramic acid residues and amidation of d -Glu in the peptide chains. Using synthetic PGN fragments incorporating these diverse PGN structures, we analyzed their binding characters through biolayer interferometry (BLI), NMR spectroscopy, and native mass spectrometry (nMS) techniques. The results of BLI showed that muropeptides containing 1,6-anhydro-MurNAc and longer glycan chains exhibited higher binding potency and that the fourth amino acid of the peptide stem, d -Ala, was crucial for protein recognition. Saturation transfer difference (STD) NMR spectroscopy indicated the major involvement of the stem peptide region in the PASTA-PGN fragment binding. nMS suggested that the binding stoichiometry was 1:1. The data provide the first molecular basis for the specific interaction of PGN with PknB and firmly establish PGNs as the effective ligands of PknB.  相似文献   
66.
In this paper, the transport characteristics of saliva droplets produced by coughing are examined in a calm indoor environment. Three subjects are studied, with results indicating that more than 6.7 mg of saliva is expelled at speeds of up to 22 m/s during each individual cough, and that saliva droplets can travel further than 2 m. In addition, the dispersion processes of saliva droplets of different diameters expelled during coughing are analyzed using the Lagrangian equation. The results indicate that the transport characteristics of saliva droplets due to coughing change with size. The effects of gravity or inertia on droplets of 30 μm or less are negligible due to their small sizes, and therefore their transport is mostly influenced by the indoor flow field. Droplets of 50–200 μm, which are significantly affected by gravity, fall as the flow-field weakens. Droplets of 300 μm or more, which are affected more by inertia than gravity, fall difficultly. Moreover, the analytical results also indicate that the droplets’ transport is greatly influenced by the spatial relationship between the air-conditioner and the subjects. Finally, based on the experimental and analytical results, droplet infection by saliva droplets due to coughing is examined.  相似文献   
67.
This study targets environmental load reduction in hot and humid regions. It reveals the effects that porous residential buildings have on the natural ventilation performance and, consequently, the cooling load reduction. Two residential building models, namely a model with a void ratio of 0% and a model with a void ratio of 50%, are evaluated using computational fluid dynamics (CFD) analysis and thermal and airflow network analysis. The analysis on components of the heat load indicates that improvements in the natural ventilation performance would significantly reduce the cooling load.  相似文献   
68.
Well size-controlled copper fine particles (diameter: 100-300?nm) were used as the inner electrode material of multilayered ceramic capacitors (MLCCs). The particles were dispersed in terpineol to form a printing paste with 50?wt% copper particles. The MLCC precursor modules prepared by the layer-by-layer printing of copper and BaTiO(3) particles were cosintered. Detailed observation of the particles, paste, and MLCCs before and after sintering was carried out by electron microscopy. The sintering temperature of Cu-MLCC was as low as 960?°C. The permittivity of these MLCCs was successfully measured with the copper inner layers.  相似文献   
69.
A novel quantitative and specific method for detection of buckwheat, a known food allergen, in diverse food materials was developed by using a unique internal standard to compensate for the variability in DNA extraction and amplification efficiencies. The method was based on a real-time PCR targeting the internal transcribed spacer region of Fagopyrum spp. and was designed to detect both cultivated and wild buckwheat, because wild buckwheat might be potentially allergenic. As the internal standard material, ground seeds of statice (Limonium sinuatum) were added to food samples prior to DNA extraction, and the amount of statice DNA measured by real-time PCR was used to standardize the buckwheat content. Statice, an ornamental plant, was chosen as the internal standard material because it was readily available and was inferred to be least likely to be commingled in foods. The specificity of the PCR system was tested against commonly used food materials of plant origin. Quantitative results expressed in buckwheat protein concentrations (mean +/- standard deviation) for various food samples prepared to contain 10 ppm (wt/wt) of buckwheat flour (corresponding to 1.2-microg/g [ppm] buckwheat protein) ranged from 0.7 +/- 0.2 (rice) to 0.9 +/- 0.4 (wheat) and for 100-ppm (wt/wt) samples (12-microg/g [ppm] buckwheat protein) from 7.7 +/- 1.0 (pepper) to 9.8 +/- 0.5 (wheat) microg/g (ppm). The method's accuracy, sensitivity, and specificity were considered sufficient for detection of buckwheat contamination at the level required for compliance with the Japanese Food Allergen Labeling Regulation.  相似文献   
70.
External Al2O3 scale formation behavior by a diffusion aluminizing process on Nb and Nb–X (X?=?Mo, Re, and Ta) alloys with different oxygen solubilities was investigated. The oxygen content in Nb and Nb–X alloys was controlled by oxygen diffusion treatment at 1,100?°C using Nb/NbO mixture. Nb–aluminide, NbAl3 and Nb2Al, layers were developed on the low-oxygen Nb substrate by an aluminum diffusion treatment using Al/Al2O3/NH4Cl mixture at 1,100?°C; whereas an adhesive Al2O3 scale developed on the Nb substrate with higher oxygen content. The alloy oxygen content decreased by an addition of Ta, Mo and Re, in this order, and the decrease in alloy oxygen content resulted in the transition of Al2O3 formation from external scale to internal precipitates. This transition was not observed when low Al activity powder mixture, Ni50Al/Al2O3/NH4Cl, was used for Al diffusion process, and only external Al2O3 scale was developed on all samples. In the present study, the effects of oxygen solubility limit, oxygen content, and the activity of Al in diffusion process on the formation of Al2O3 scale will be discussed.  相似文献   
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