[1] The recalcitrant properties of black carbon (BC) grant it to be a significant pool of stable organic C (OC) in soils. Up to now, however, the longevity of BC under different climates is still unclear. In this study, we used BC samples from historical charcoal blast furnace sites to examine the stability of BC across a climatic gradient of mean annual temperatures (MAT) from 3.9 to 17.2°C. The results showed that OC concentration and OC storage in the BC-containing soils at a soil depth of 0-0.2 m were 9.0 and 4.7 times higher than those in adjacent soils, respectively. Organic C in the BC-containing soils was more stable, with a significantly lower amount of the labile OC fraction (4.4 mg g À1 OC versus 27.5 mg g À1 OC) and longer half-life of the recalcitrant OC fraction (59 years versus 9 years) than the adjacent soils determined by incubation experiments. The stability of BC was primarily due to its inherently recalcitrant chemical composition as suggested by short-term incubation and solid state 13 C nuclear magnetic resonance spectra of isolated BC particles. A significant negative relationship between OC storage and MAT further indicated that OC storage was decreased with warmer climate. However, the lack of a relationship between MAT and BC mineralization suggested that the stability of the remaining BC was similar between sites with very different MAT. Despite the fact that warming or cooling result in immediate consequences for BC stocks, it may have little impact on the stability of remaining BC over the period studied.
Electroacupuncture (EA) possesses various therapeutic effects, including alleviation of pain, reduction of inflammation and improvement of sleep disturbance. The mechanisms of EA on sleep improvement, however, remain to be determined. It has been stated in ancient Chinese literature that the Anmian (EX17) acupoint is one of the trigger points that alleviates insomnia. We previously demonstrated that EA stimulation of Anmian acupoints in rats during the dark period enhances non-rapid eye movement (NREM) sleep, which involves the induction of cholinergic activity in the nucleus tractus solitarius (NTS). In addition to cholinergic activation of the NTS, activation of the endogenous opioidergic system may also be a mechanism by which acupuncture affects sleep. Therefore, this study was designed to investigate the involvement of the NTS opioidergic system in EA-induced alterations in sleep. Our present results indicate that EA of Anmian acupoints increased NREM sleep, but not rapid eye movement sleep, during the dark period in rats. This enhancement in NREM sleep was dose-dependently blocked by microinjection of opioid receptor antagonist, naloxone, and the μ-opioid receptor antagonist, naloxonazine, into the NTS; administrations of δ-receptor antagonist, natrindole, and the κ-receptor antagonist, nor-binaltrophimine, however, did not affect EA-induced alterations in sleep. Furthermore, β-endorphin was significantly increased in both the brainstem and hippocampus after the EA stimuli, an effect blocked by administration of the muscarinic antagonist scopolamine into the NTS. Our findings suggest that mechanisms of EA-induced NREM sleep enhancement may be mediated, in part, by cholinergic activation, stimulation of the opiodergic neurons to increase the concentrations of β-endorphin and the involvement of the μ-opioid receptors.
Hematologic analyses are useful for the monitoring of animal health and diseases and for the differentiation of physiologic processes for clinicians and conservationists. In order to establish hematology reference values for the Chinese striped-necked [corrected] turtle (Ocadia sinensis) and to produce an accurate baseline of clinical laboratory data for O. sinensis with regard to sex and season, 50 (24 males and 26 females) adult captive individuals of O. sinensis were studied. Blood samples from the jugular veins of the turtles were collected in January, April, June, and November. Data were analyzed using repeated measures analysis of variance for significant (P < 0.05) variation by sex, season, and the interaction between sex and season. Significant sex differences were observed for the parameters of packed cell volume, eosinophil count, heterophils and monocytes ratio, total protein, albumin, uric acid, aspartate aminotransferase, alanine aminotransferase, triglycerides, cholesterol, and alkaline phosphatase. Marked seasonal variation was noted in all parameters except mean cell hemoglobin, monocytes and heterophils ratio, and creatinine. Differences between sexes and seasons were primarily associated with the reproductive cycle. Heterophils had a strong positive reaction and eosinophils had a moderate positive reaction to benzidine peroxidase stain. Thrombocytes had a positive reaction to periodic acid-Schiff stain. Surface morphologic study using scanning electron microscopy of blood cells showed that white blood cells of O. sinensis had no distinctive surface characteristics.
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