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The minerals in the hydrothermal and cold seep system form at different temperatures and show responses to the laser power to varying degrees. Here, we focus on the heat-induced by laser to study thermal transformations of the chalcopyrite, covellite, pyrite, barite, and aragonite based on Raman spectroscopy. Chalcopyrite mainly transforms into hematite, and covellite mainly transforms into chalcocite with the increase of laser power. Interestingly, comparing with the previous study, the pyrite can transform to the marcasite firstly, and form hematite finally. We also find that high-temperature opaque chalcopyrite is more likely to occur thermal transformations due to the smaller absolute energy difference (|ΔE1|) based on the frontier orbital theory. In contrast, the oxysalt minerals won’t transform into new components under high laser power. However, the structure of the barite has been destroyed by the high laser power, while the more transparent aragonite is not affected by the high laser power due to the laser penetrates through the transparent aragonite crystal and causes little heat absorption. Finally, we established the minimum laser power densities for thermal transformations of these minerals formed under different environments. The above study provides a simple way to study the thermal transformations of minerals by the local heat-induced by laser and also enlightens us to identify the minerals phases precisely.

Background Nowadays, many cytotoxic anticancer drugs exhibit low solubility and poor tumor selectivity, which means that the drug formulation is very important. For example, in the case of paclitaxel (PTX), Cremophor EL ® (BASF, Ludwigshafen, Germany) needs to be used as a solubilizer in its clinical formulation (Taxol ® , Bristol-Myers Squibb, New York, NY), although it can cause serious side effects. Nanomicellar systems are promising carriers to resolve the above problems, and the polymer chosen is the key element. Methods In this study, a novel amphiphilic chitosan/vitamin E succinate (CS-VES) copolymer was successfully synthesized for self-assembling polymeric micelles. Proton nuclear magnetic resonance spectroscopy and infrared were used to characterize the molecular structure of the copolymer. The PTX-loaded CS-VES polymeric micelles (PTX-micelles) were characterized by dynamic light scattering, transmission electron microscopy, X-ray diffraction, and differential scanning calorimetry. Results The critical micelle concentration of CS-VES was about 12.6 μg/mL, with the degree of amino group substitution being 20.4%. PTX-micelles were prepared by a nanoprecipitation/dispersion technique without any surfactant being involved. PTX-micelles exhibited a drug loading as high as 21.37% and an encapsulation efficiency of 81.12%, with a particle size ranging from 326.3 to 380.8 nm and a zeta potential of +20 mV. In vitro release study showed a near zero-order sustained release, with 51.06%, 50.88%, and 44.35% of the PTX in the micelles being released up to 168 hours at three drug loadings of 7.52%, 14.09%, and 21.37%, respectively. The cellular uptake experiments, conducted by confocal laser scanning microscopy, showed an enhanced cellular uptake efficiency of the CS-VES micelles in MCF-7 cells compared with Taxol. The PTX-micelles exhibited a comparable but delayed cytotoxic effect compared with Taxol against MCF-7 cells, due to the sustained-release characteristics of the nanomicelles. More interestingly, blank nanomicelles based on CS-VES copolymer demonstrated significant cytotoxicity against MCF-7 cells. Conclusion The supramolecular micellar aggregates based on CS-VES copolymer is a promising nanocarrier and efficacy enhancer when used as an anticancer drug-delivery system.

An outbreak of enterically transmitted hepatitis occurred during 1996 among students at a vocational school. Viral fragments homologous to transfusion-transmitted virus (TTV) were detected in faeces. To elucidate the endemic status, an epidemiological survey and case follow-up after the outbreak were carried out. During and after the outbreak, virus carriers among staff were, respectively, 32.1% and 31.3% in serum, and 24.6% and 18.2% in faeces. After the last outbreak, attacks were still occurring among new students with an incidence of 2.4% in 1997 and 2.3% in 1998. There was also a small-scale outbreak in 1998 with a prevalence of 17.9%. On follow-up at 6 and 18 months after onset, alanine aminotransferase (ALT) elevation was found in 29.7% and 13.9% of patients. At 6 months, viral fragments were detected in serum in 78.1% and 46.7% of patients, with and without ALT elevation, respectively. At 18 months the corresponding figures were 55.6% and 19.2%, respectively. At the 18-month follow-up, viral fragments were detected in faeces in 29.6% and 19.3% of patients with and without ALT elevation. In conclusion, this disease might be transmitted from asymptomatic virus carriers. According to the laboratory data, both parenteral and non-parenteral transmissions are involved, and the faecal-oral route might be more important.