49 research outputs found
Microfluidic synthesis of monodisperse and size-tunable CsPbBr3 supraparticles
The highly controlled, microfluidic template-assisted self-assembly of CsPbBr3 nanocrystals into spherical supraparticles is presented, achieving precise control over average supraparticle size through the variation of nanocrystal concentration and droplet size; thus facilitating the synthesis of highly monodisperse, sub-micron supraparticles (with diameters between 280 and 700 nm)
Bear bile: dilemma of traditional medicinal use and animal protection
Bear bile has been used in Traditional Chinese Medicine (TCM) for thousands of years. Modern investigations showed that it has a wide range of pharmacological actions with little toxicological side effect and the pure compounds have been used for curing hepatic and biliary disorders for decades. However, extensive consumption of bear bile made bears endangered species. In the 1980's, bear farming was established in China to extract bear bile from living bears with "Free-dripping Fistula Technique". Bear farming is extremely inhumane and many bears died of illness such as chronic infections and liver cancer. Efforts are now given by non-governmental organizations, mass media and Chinese government to end bear farming ultimately. At the same time, systematic research has to be done to find an alternative for bear bile. In this review, we focused on the literature, laboratory and clinical results related to bear bile and its substitutes or alternative in English and Chinese databases. We examined the substitutes or alternative of bear bile from three aspects: pure compounds derived from bear bile, biles from other animals and herbs from TCM. We then discussed the strategy for stopping the trading of bear bile and issues of bear bile related to potential alternative candidates, existing problems in alternative research and work to be done in the future
Analysis of the Henze precipitate from the blood cells of the ascidian Phallusia mammillata.
The Henze precipitate, a peculiar blue-green microparticulate obtained by lysis of the blood cells of the ascidian Phallusia mammillata (Protochordata), was investigated with atomic force microscopy (AFM), scanning electron microscopy (SEM) and X-ray microanalysis. The precipitate was collected from the Henze solution, an unstable red-brown product obtained by treating blood with distilled water, whose degradation yields a characteristic blue-green product. The microparticulates measured 50–100 µm in diameter and appeared irregular in shape. SEM examination showed smooth, roughly round boundaries. The microparticulate surface examined with AFM appeared as an irregular matrix formed by 70–320-nm-wide mammillate composites, including and embedding small (500–800 nm wide) crystal-like multilayered formations. X- ray analysis showed that the elements present in these same precipitates were mainly C, Si, Al and O. The microparticulate composition appeared close to those of natural waxes or lacquers, embedding amorphous silicates and/or other Si–Al components. The unusual occurrence of Si in ascidian blood and its role are discussed
ELEMENTAL COMPOSITION OF INCISORS IN NOVA SCOTIA MOOSE: EVALUATION OF A POPULATION WITH ABNORMAL INCISOR BREAKAGE
This study compared the concentrations of major and trace elements in the enamel of incisors from moose (Alces alces andersoni) in Cape Breton Highlands, where the incidence of incisor tooth breakage was believed to be unusually high, and moose in southwest Nova Scotia (A. a. americana) where there was no evidence of breakage. Our goal was to determine which elements, if any, might be related to the incisor breakage in moose from Cape Breton Highlands. There was a positive relationship between age and frequency of incisor breakage, and most moose had a broken I2 incisor by 4 years of age in the Cape Breton Highlands. We analyzed I2 incisors for 51 trace elements with Inductively Coupled Plasma-Mass Spectrometry. Concentrations of 8 elements, including barium, beryllium, cadmium, cobalt, lead, tin, strontium, and yttrium, were lower (P < 0.05) in incisors from Cape Breton Highlands; gallium had a higher concentration. Reduced intake of barium, beryllium, and strontium is linked to depressed growth and reduced calcification of bones and teeth
Rapid identification of long-chain polyunsaturated fatty acids in a marine extract by HPLC-MS using data-dependent acquisition
The collision-induced dissociation (CID) of a range of deprotonated fatty acid standards was studied using linear ion trap mass spectrometry. Neutral losses of 78, 98, and 136 Da were consistently observed for fatty acids with five or more double bonds. Comparison of the MS/MS spectra of docosahexaenoic acid (DHA) and universally C-13-labeled DHA allowed the molecular formulas for these neutral losses to be determined as C6H6, C5H6O2, and C8H8O2. Knowledge of fatty acid fragmentation processes was then applied to identify fatty acids from a sea anemone, Aiptasia pulchella, and dinoflagellate symbiont, Symbiodinium sp. extract Using HPLC-MS, fatty acids were separated and analyzed by tandem mass spectrometry in data dependent acquisition mode. Neutral loss chromatograms for 78, 98, and 136 Da allowed the identification of long chain fatty acids with five or more double bonds. On the basis of precursor ion m/z ratios, chain length and degree of unsaturation for these fatty acids were determined. The application of this technique to an Aiptasia sp. Symbiodinium sp lipid extract enabled the identification of the unusual, long chain fatty acids 24:6, 26:6, 26:7, 28:7, and 28:8 during a single 40 min HPLC-MS analysis