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We investigated the effects of different operating temperatures on the performance of transport critical current density, Jc, for MgB2 + 10 wt%C4H6O5MgB2/Fe wires. It was shown that the Jc values of the malic acid doped wires sintered at 900°C reached 104 Acm-2 at 20 K and 5 T. The Jc value extrapolated to 2 T and 20 K exceeds the practical level of 105 Acm-2. According to the Kramer plots, the pinning force, FK = Jc1/2 x B1/4, is expected to be a linear function of magnetic field B. The irreversibility field, Birr, at which extrapolated FK reaches zero, was 1.8 T at 32.8 K, 2.8 T at 30 K, 5.7 T at 25 K, 8.6 T at 20 K, and 12.5 T at 15 K, respectively.
We propose a novel stress sensing methods using water soluble, sugar-displaying quantum dot and digitonin-permeabilized semi-intact HeLa cells. The amount of GlcNAc-QDs (N-acetylglucosamine-displaying quantum dots) binding to heavy metal ion exposed cells was investigated by fluorescence intensity, and it increased in a dose-dependent manner. This result suggests that GlcNAc-QD could be applied for a new stress sensing probe.
Using a Cu(I)-catalyzed carbohydrate azide-alkynylphenylporphyrin cycloaddition (the so-called "click" chemistry), we have synthesized in high yields, a series of four new porphyrin-carbohydrate conjugates containing either one or four galactose or lactose moieties linked via triazole units to a meso-phenyl group of a TPP or tetrabenzoporphyrin (TBP) macrocycle. The time-dependent uptake and subcellular distribution of this series of porphyrin-carbohydrate conjugates were evaluated in human carcinoma HEp2 cells. While the three TPP conjugates accumulated to a similar extent within cells and localized mainly in the ER and endosomes, the TBP-galactose conju gate was the one most efficiently taken up by the HEp2 cells, accumulating approximately 5 times more than the TPP conjugates, and localized preferentially within the cell lysosomes.
Carbohydrates on cell surfaces play a crucial role in a wide variety of biological processes, including cell adhesion, recognition and signaling, viral and bacterial infection, inflammation and metastasis. However, owing to the large diversity and complexity of carbohydrate structure and nongenetically synthesis, glycoscience is the least understood field compared with genomics and proteomics. Although the structures and functions of carbohydrates have been investigated by various conventional analysis methods, the distribution and role of carbohydrates in cell membranes remain elusive. This review focuses on the developments and challenges of super-resolution imaging in glycoscience through introduction of imaging principle and the available fluorescent probes for super-resolution imaging, the labeling strategies of carbohydrates, and the recent applications of super-resolution imaging in glycoscience, which will promote the super-resolution imaging technology as a promising tool to provide new insights into the study of glycoscience.
This manuscript describes a general and simple method to carbon-coat quantum dots (QDs) using microwave-assisted technology. By coating QDs with carbohydrates, you extend their application for bioimaging (in vitro and in vivo) as the metal core is now shielded by a protective coating layer. XRD and TEM verified that nanoparticles were coated with a layer of carbon-based material (reduced sucrose). In addition, we demonstrated the versatility of this approach by coating other types of nanoparticles (i.e. gold). UV–Visible spectroscopic analysis presented a red shift in absorbance after carbon coating which further confirmed that the surface of these nanoparticles was modified. QDs emission wavelength was not altered but experienced an increase in intensity. The carbon-coated QDs and gold nanoparticles generated in this study measured 14 nm and 60 nm, respectively.
Some people think that carbon and sustainable development are not compatible. This textbook shows that carbon dioxide (CO2) from the air and bio-carbon from biomass are our best allies in the energy transition, towards greater sustainability. We pose the problem of the decarbonation (or decarbonization) of our economy by looking at ways to reduce our dependence on fossil carbon (coal, petroleum, natural gas, bitumen, carbonaceous shales, lignite, peat). The urgent goal is to curb the exponential increase in the concentration of carbon dioxide in the atmosphere and hydrosphere (Figures 1.1 and 1.2) that is directly related to our consumption of fossil carbon for our energy and materials The goal of the Paris agreement (United Nations COP 21, Dec. 12, 2015) of limiting the temperature increase to 1.5 degrees (compared to the pre-industrial era, before 1800) is becoming increasingly unattainable (Intergovermental Panel on Climate Change (IPCC), report of Aug. 6, 2021). On Aug. 9, 2021 Boris Johnson, prime minister of the United Kingdom, declared that coal needs to be consigned to history to limit global warming. CO2 has an important social cost…
The sun is the only source of renewable energy available to us, if geothermal energy is not taken into account. In the form of radiation (UV light, visible light, infrared light, Section 1.1) it sends us annually 178,000 terawatts (1 TW = 1012 W; unit of power 1 W = 1 J s–1 = 859.85 calories per hour), that is to say 15,000 times the energy consumed annually by humanity. Only 0.1% of the solar energy received by planet Earth is converted into plant biomass, i.e. 100 × 109 tons per year which corresponds to ca. 180 × 109 tons per year of CO2 captured from the atmosphere. This CO2 returns to the biosphere after the death of the plants. Consumption of fossil carbon emits ca. 35 × 109 tons of CO2 yearly. Biomass is the material produced by all living organisms (plants, animals, microorganisms, fungi)…