3,773 research outputs found
Optical Monitoring of the Seyfert Galaxy NGC 4151 and Possible Periodicities in the Historical Light Curve
We report B, V, and R band CCD photometry of the Seyfert galaxy NGC 4151
obtained with the 1.0-m telescope at Weihai Observatory of Shandong University
and the 1.56-m telescope at Shanghai Astronomical Observatory from 2005
December to 2013 February. Combining all available data from literature, we
have constructed a historical light curve from 1910 to 2013 to study the
periodicity of the source using three different methods (the Jurkevich method,
the Lomb-Scargle periodogram method and the Discrete Correlation Function
method). We find possible periods of P_1=4\pm0.1, P_2=7.5\pm0.3 and
P_3=15.9\pm0.3 yr.Comment: 8 pages, 5 figures, Accepted by Research in Astronomy and
Astrophysic
Disodium dihydrogen pyridine-2,3,5,6-tetraÂcarboxylÂate trihydrate
In the title compound, 2Na+·C9H3NO8
2−·3H2O, the asymmetric unit consists of two Na+ cations, one dihydrogen pyridine-2,3,5,6-tetraÂcarboxylÂate dianion (H2pdtc2−) and three water molÂecules coordinated to the Na+ cations. The configuration of the anion is stabilized by intramolecular O—H⋯O hydrogen bonding between vicinal carboxylate/carboxy groups. The Na+ cations are bridged by the H2pdtc2− dianions, generating layers extending infinitely in sheets parallel to (001), and further pillared by the water molÂecule linkers to build up a three-dimensional framework
Recommended from our members
Low-Level Saturated Fatty Acid Palmitate Benefits Liver Cells by Boosting Mitochondrial Metabolism via CDK1-SIRT3-CPT2 Cascade.
Saturated fatty acids (SFAs) (the "bad" fat), especially palmitate (PA), in the human diet are blamed for potential health risks such as obesity and cancer because of SFA-induced lipotoxicity. However, epidemiological results demonstrate a latent benefit of SFAs, and it remains elusive whether a certain low level of SFAs is physiologically essential for maintaining cell metabolic hemostasis. Here, we demonstrate that although high-level PA (HPA) indeed induces lipotoxic effects in liver cells, low-level PA (LPA) increases mitochondrial functions and alleviates the injuries induced by HPA or hepatoxic agent carbon tetrachloride (CCl4). LPA treatment in mice enhanced liver mitochondrial activity and reduced CCl4 hepatotoxicity with improved blood levels of aspartate aminotransferase (AST), alanine transaminase (ALT), and mitochondrial aspartate transaminase (m-AST). LPA-mediated mitochondrial homeostasis is regulated by CDK1-mediated SIRT3 phosphorylation, which in turn deacetylates and dimerizes CPT2 to enhance fatty acid oxidation. Thus, an advantageous effect is suggested by the consumption of LPA that augments mitochondrial metabolic homeostasis via CDK1-SIRT3-CPT2 cascade
Effect of Paris polyphylla extract on second-degree burns in rats
Purpose: To investigate the healing effect of Paris polyphylla extract (PPE) on second-degree burns in rats.Methods: Male Sprague Dawley (SD) rats, weighing 200 – 220 g, were subjected to deep seconddegree skin burns by electrical scald instrument. The animals were divided into three groups as follows: (1) second-degree burn model (control) group, (2) burn model treated with 1 % silver sulfadiazine (SSD) group, and (3) burn model treated with 120 mg·mL-1 PPE group. On days 3, 7 and 14 following the administration of the drug/extract, wound area and histopathological changes in rat epidermis were evaluated for the three groups. The minimum inhibitory concentration (MIC) of PPE on Staphyloccocus aureus, Pseudomonas aeruginosa and Escherichia coli were also assessed.Results: On day 14, the mean wound area of PPE treatment group (0.21 ± 0.04 cm2) was significantly smaller than that of the control rats (2.78 ± 0.18 cm2, p < 0.01). Histological results indicate that inflammatory cells disappeared and were replaced by new granulation tissue in the group treated with 120 mg·mL-1 PPE by day 14. Compared with SSD group rats, the inflammatory cells and fibroblast and granulation tissues of burnt rats with burns and treated with 120 mg·mL-1 PPE decreased significantly. The antibacterial data revealed that the MIC of PPE against S. aureus, P. aeruginosa and E. coli was 2.35, 8.2 and 4.70 mg·mL-1, respectively.Conclusion: Paris polyphylla is an effective medicinal herb that holds promise for the treatment of second-degree burns.Keywords: Paris polyphylla, Second-degree burns, Wound healing, Antibacterial, Inflammatory cells, Granulation tissues, Silver sulfadiazin
- …