A compilation of known QSOs for the Gaia mission

Quasars are essential for astrometric in the sense that they are spatial stationary because of their large distance from the Sun. The European Space Agency (ESA) space astrometric satellite Gaia is scanning the whole sky with unprecedented accuracy up to a few muas level. However, Gaia's two fields of view observations strategy may introduce a parallax bias in the Gaia catalog. Since it presents no significant parallax, quasar is perfect nature object to detect such bias. More importantly, quasars can be used to construct a Celestial Reference Frame in the optical wavelengths in Gaia mission. In this paper, we compile the most reliable quasars existing in literatures. The final compilation (designated as Known Quasars Catalog for Gaia mission, KQCG) contains 1843850 objects, among of them, 797632 objects are found in Gaia DR1 after cross-identifications. This catalog will be very useful in Gaia mission

A novel multifunctional biomedical material based on polyacrylonitrile:preparation and characterization

Wet spun microfibers have great potential in the design of multifunctional controlled release materials. Curcumin (Cur) and vitamin E acetate (Vit. E Ac) were used as a model drug system to evaluate the potential application of the drug-loaded microfiber system for enhanced delivery. The drugs and polyacrylonitrile (PAN) were blended together and spun to produce the target drug-loaded microfiber using an improved wet-spinning method and then the microfibers were successfully woven into fabrics. Morphological, mechanical properties, thermal behavior, drug release performance characteristics, and cytocompatibility were determined. The drug-loaded microfiber had a lobed “kidney” shape with a height of 50 ~ 100 μm and width of 100 ~ 200 μm. The addition of Cur and Vit. E Ac had a great influence on the surface and cross section structure of the microfiber, leading to a rough surface having microvoids. X-ray diffraction and Fourier transform infrared spectroscopy indicated that the drugs were successfully encapsulated and dispersed evenly in the microfilament fiber. After drug loading, the mechanical performance of the microfilament changed, with the breaking strength improved slightly, but the tensile elongation increased significantly. Thermogravimetric results showed that the drug load had no apparent adverse effect on the thermal properties of the microfibers. However, drug release from the fiber, as determined through in-vitro experiments, is relatively low and this property is maintained over time. Furthermore, in-vitro cytocompatibility testing showed that no cytotoxicty on the L929 cells was found up to 5% and 10% respectively of the theoretical drug loading content (TDLC) of curcumin and vitamin E acetate. This study provides reference data to aid the development of multifunctional textiles and to explore their use in the biomedical material field

Effects of the endoparasitoid Cotesia chilonis (Hymenoptera: Braconidae) parasitism, venom, and calyx fluid on cellular and humoral immunity of its host Chilo suppressalis (Lepidoptera: Crambidae) larvae

AbstractThe larval endoparasitoid Cotesia chilonis injects venom and bracoviruses into its host Chilo suppressalis during oviposition. Here we study the effects of the polydnavirus (PDV)-carrying endoparasitoid C. chilonis (Hymenoptera: Braconidae) parasitism, venom and calyx fluid on host cellular and humoral immunity, specifically hemocyte composition, cellular spreading, encapsulation and melanization. Total hemocyte counts (THCs) were higher in parasitized larvae than in unparasitized larvae in the late stages following parasitization. While both plasmatocyte and granulocyte fractions and hemocyte mortality did not differ between parasitized and unparasitized hosts, in vitro spreading behavior of hemocytes was inhibited significantly by parasitism throughout the course of parasitoid development. C. chilonis parasitism suppressed the encapsulation response and melanization in the early stages. Venom alone did not alter cellular immune responses, including effects on THCs, mortality, hemocyte composition, cell spreading and encapsulation, but venom did inhibit humoral immunity by reducing melanization within 6h after injection. In contrast to venom, calyx fluid had a significant effect on cell spreading, encapsulation and melanization from 6h after injection. Dose–response injection studies indicated the effects of venom and calyx fluid synergized, showing a stronger and more persistent reduction in immune system responses than the effect of either injected alone

The Modulatory Role of CYP3A4 in Dictamnine-Induced Hepatotoxicity

Dictamni Cortex (DC) has been reported to be associated with acute hepatitis in clinic and may lead to a selective sub-chronic hepatotoxicity in rats. Nevertheless, the potent toxic ingredient and the underlying mechanism remain unknown. Dictamnine (DTN), the main alkaloid from DC, possesses a furan ring which was suspected of being responsible for hepatotoxicity via metabolic activation primarily by CYP3A4. Herein, the present study aimed to evaluate the role of CYP3A4 in DTN-induced liver injury. The in vitro results showed that the EC50 values in primary human hepatocytes (PHH), L02, HepG2 and NIH3T3 cells were correlated with the CYP3A4 expression levels in corresponding cells. Furthermore, the toxicity was increased in CYP3A4-induced PHH by rifampicin, and CYP3A4 over-expressed (OE) HepG2 and L02 cells. Contrarily, the cytotoxicity was decreased in CYP3A4-inhibited PHH and CYP3A4 OE HepG2 and L02 cells inhibited by ketoconazole (KTZ). In addition, the hepatotoxicity of DTN in enzyme induction/inhibition mice was further investigated in the aspects of biochemistry, histopathology, and pharmacokinetics. Administration of DTN in combination with KTZ resulted in attenuated liver injury, including lower alanine transaminase and aspartate transaminase activities and greater AUC and Cmax of serum DTN, whereas, pretreatment with dexamethasone aggravated the injury. Collectively, our findings illustrated that DTN-induced hepatotoxicity correlated well with the expression of CYP3A4, namely inhibition of CYP3A4 alleviated the toxicity both in vitro and in vivo, and induction aggravated the toxicity effects

The Protective Effect of Cordymin, a Peptide Purified from the Medicinal Mushroom Cordyceps sinensis, on Diabetic Osteopenia in Alloxan-Induced Diabetic Rats

The aim of this study was to investigate the protective effect of cordymin on diabetic osteopenia in alloxan-induced diabetic rats and the possible mechanisms involved. The diabetic rats received daily intraperitoneal injection with cordymin (20, 50, and 100 mg/kg/day) for 5 weeks. Cordymin could restore the circulating blood glucose, glycosylated hemoglobin (HbA1c), serum alkaline phosphatase (ALP), tartrate resistant acid phosphatase (TRAP), and insulin levels in a dose-dependent manner. Also, the treatment of diabetic rats with cordymin could partially reverse the β cells death and decrease the total antioxidant status (TAOS) in the diabetic rats. The results may directly and indirectly account for the possible mechanism of the beneficial effect of cordymin on diabetic osteopenia, which was confirmed with the increased bone mineral content (BMC) and bone mineral density (BMD) in diabetic rats (P<0.05). All those findings indicate that cordymin may play a protective role in diabetic osteoporosis

Fully Band Resolved Scattering Rate in MgB2 Revealed by Nonlinear Hall Effect and Magnetoresistance Measurements

We have measured the normal state temperature dependence of the Hall effect and magnetoresistance in epitaxial MgB2 thin films with variable disorders characterized by the residual resistance ratio RRR ranging from 4.0 to 33.3. A strong nonlinearity of the Hall effect and magnetoresistance have been found in clean samples, and they decrease gradually with the increase of disorders or temperature. By fitting the data to the theoretical model based on the Boltzmann equation and ab initio calculations for a four-band system, for the first time, we derived the scattering rates of these four bands at different temperatures and magnitude of disorders. Our method provides a unique way to derive these important parameters in multiband systems.Comment: 4 pages, 4 figure

The global progress on the non-point source pollution research from 2012 to 2021: a bibliometric analysis

Background: With effective control of point source pollution, non-point source (NPS) pollution has been widely concerned as the primary reason for the improvement of global water environmental quality. Some bibliometric analysis related to NPS pollution has been carried out before the mid-2010s. Analyzing the research status and hot issues of NPS pollution in the past decade is important for guiding the control and management of NPS pollution in the future. Results: A bibliometric analysis was conducted based on 3407 publications retrieved from the Web of Science during 2012–2021. China, USA and UK were the most productive countries. Sci. Total Environ, Environ. Sci. Pollut. Res, and Water were the most productive journals. The NPS pollutant, pollution types, driving forces, technology and the research object were retrieved from the keywords analysis. The common NPS pollutants of nitrogen, phosphorus, and heavy metals grabbed the highest attention, while the emerging contaminants have attracted increased attention. The migration and transformation of agricultural NPS pollution and urban NPS pollution driven by climate change and land use change were hot issues related to NPS pollution studies. Technologies related to the combination of 3S technology (RS, GIS, and GPS) and NPS pollution models, the sustainable control technologies, the technology of accurate traceability and automatic monitoring, and the comprehensive management plan were the important research areas related to NPS pollution. Although the research locations were mostly concentrated in the surface water and groundwater, the ocean and drinking water have great potential for future research. Conclusions: This study illustrates the global focuses related to NPS pollution during 2012–2021 according to analyzing the publication outputs, source journals, source country, author, institution and the high-frequency keywords. Results demonstrated that the migration and transformation mechanism and ecological risk assessment for heavy metals and emerging pollutants, accurate traceability techniques, sustainable ecological restoration control techniques, and marine pollution have attracted rising attention. Additionally, developing countries will have a higher interest in NPS pollution in the future, because developed countries have already made great progress in controlling NPS pollution

Development of a 1-THz 4th-harmonic gyrotron

A design of a 1-THz 4th Harmonic Gyrotron is proposed in this paper. Fourth harmonic interaction is adopted to lower the strength of the external magnet. The magnet can be as low as 10T. Such a low-intensity magnetic field can be easily proposed by a superconduct magnet, which make the generation of continuous waves at 1 THz possible. Seeing that the mode competition is extremely fierce, a large orbit gun is employed as the driven source. An 80-kV, 0.7-A electron beam is injected into the interaction circuit to excite the fourth-harmonic electromagnetic waves. According to the cold dispersive diagram, the TE4, 8 mode of the cylindrical waveguide is selected as the operating mode to further suppress the mode competition induced by the fundamental modes, the 2nd harmonic modes and the 3rd harmonic modes. It could be inferred based on the multi-mode time-domain theory that an output power of 1.15 kW can be achieved. The scheme diagram for the hot test is proposed. The LOG is chosen as the electron gun. Particular structure is employed for improving the output efficiency in the interaction circuit