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81.
Near-infrared (NIR) spectroscopic analysis of noncrystalline polyols and saccharides (e.g., glycerol, sorbitol, maltitol,
glucose, sucrose, maltose) was performed at different temperatures (30–80°C) to elucidate the effect of glass transition on
molecular interaction. Transmission NIR spectra (4,000–12,000 cm−1) of the liquids and cooled-melt amorphous solids showed broad absorption bands that indicate random configuration of molecules.
Heating of the samples decreased an intermolecular hydrogen-bonding OH vibration band intensity (6,200–6,500 cm−1) with a concomitant increase in a free and intramolecular hydrogen-bonding OH group band (6,600–7,100 cm−1). Large reduction of the intermolecular hydrogen-bonding band intensity at temperatures above the glass transition (T
g) of the individual solids should explain the higher molecular mobility and lower viscosity in the rubber state. Mixing of
the polyols with a high T
g saccharide (maltose) or an inorganic salt (sodium tetraborate) shifted both the glass transition and the inflection point
of the hydrogen-bonding band intensity to higher temperatures. The implications of these results for pharmaceutical formulation
design and process monitoring (PAT) are discussed. 相似文献
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Nakamura K Ikeda S Matsuo T Hirata A Takehara M Hiyama T Kawamura F Kusaka I Tsuchiya T Kuroda T Yabe I 《Biochimica et biophysica acta》2011,1808(4):1103-1107
Bacillus subtilis is a representative Gram-positive bacterium. In aerobic conditions, this bacterium can generate an electrochemical potential across the membrane with aerobic respiration. Here, we developed the patch clamp method to analyze the respiratory chain in B. subtilis. First, we prepared giant protoplasts (GPs) from B. subtilis cells. Electron micrographs and fluorescent micrographs revealed that GPs of B. subtilis had a vacuole-like structure and that the intravacuolar area was completely separated from the cytoplasmic area. Acidification of the interior of the isolated and purified vacuole-like structure, due to H(+) translocation after the addition of NADH, revealed that they consisted of everted cytoplasmic membranes. We called these giant provacuoles (GVs) and again applied the patch clamp technique. When NADH was added as an electron donor for the respiratory system, a significant NADH-induced current was observed. Inhibition of KCN and 2-heptyl-4-hydroxyquinoline-N-oxide (HQNO) demonstrated that this current is certainly due to aerobic respiration in B. subtilis. This is the first step for more detailed analyses of respiratory chain in B. subtilis, especially H(+) translocation mechanism. 相似文献
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The effect of NADP+ on light-induced steady-state redox changes of membrane-bound cytochromes was investigated in membrane fragements prepared from the blue-green algae Nostoc muscorum (Strain 7119) that had high rates of electron transport from water to NADP+ and from an artificial electron donor, reduced dichlorophenolindophenol (DCIPH2) to NDAP+. The membrane fragments contained very little phycocyanin and had excellent optical properties for spectrophotometric assays. With DCIPH2 as the electron donor, NADP+ had no effect on the light-induced redox changes of cytochromes: with or without NADP+, 715- or 664-nm illumination resulted mainly in the oxidation of cytochrome f and of other component(s) which may include a c-type cytochrome with an alpha peak at 549nm. With 664 nm illumination and water as the electron donor, NADP+ had a pronounced effect on the redox state of cytochromes, causing a shift toward oxidation of a component with a peak at 549 nm (possibly a c-type cytochrome), cytochrome f, and particularly cytochrome b559. Cytochrome b559 appeared to be a component of the main noncyclic electron transport chain and was photooxidized at physiological temperatures by Photosystem II. This photooxidation was apparent only in the presence of a terminal acceptor (NADP+) for the electron flow from water. 相似文献
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Geographical distribution of morphological abnormalities and wing color pattern modifications of the pale grass blue butterfly in northeastern Japan 下载免费PDF全文
Atsuki Hiyama Wataru Taira Mayo Iwasaki Ko Sakauchi Raj Gurung Joji M. Otaki 《Entomological Science》2017,20(1):100-110
The pale grass blue butterfly Zizeeria maha has been used as an environmental indicator to evaluate the biological impacts of the Fukushima nuclear accident. A high morphological abnormality rate (AR) of this butterfly was detected in 2011 from radioactively contaminated areas at 37–38°N. However, the geographical AR distribution has not been documented for the entirety of northeastern Japan. Additionally, the geographical distribution of the wing color pattern modification rate (MR) of temperature‐shock type remains undocumented. Here, we collected adult butterflies from many localities in northeastern Japan in 2014 and examined the local AR and MR. Both AR and MR were generally low throughout the 44 local populations surveyed. Latitudinal AR and MR distributions indicated a gap zone at approximately 39°N. The mean AR and the mean MR of the populations south of the gap zone were low (AR = 3.0%, MR = 1.1%), whereas those of the northern populations were relatively high (AR = 10.6%, MR =10.3%). Logistic regression analyses revealed that abnormalities and modifications were associated with temperature‐related variables. We conclude that abnormalities and modifications are generally rare, but that their rates are higher in the northern populations than in the southern ones. These results, along with evidence from other studies, strongly suggest that the high AR detected in 2011 from contaminated areas was induced by anthropogenic radioactive mutagens. This study presents a basic dataset of the current wildlife state of Z. maha in northeastern Japan, which facilitates a future use of this butterfly species as an environmental indicator. 相似文献
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