RESUMO
The quality of bitumen directly affects road performance and road life. Traditional analytical methods-for wax content, softening point and penetration of bitumen are tedious and time-consuming. A new fast method, with which the three properties can be determined at same time, is proposed in this paper. The spectra of 220 bitumen were collected and their wax content, softening point and penetration data were determined according to the standard JTJ052-2000. The quantitative calibration models for wax content, softening point and penetration were established using partial least squares (PLS), with SECV 0.13, 0.88, 3.18 and SEP 0.14, 1.06, 3.90, less than the reproducibility error stipulated in the standard method. Three samples were in random selected to test the repeatability, the results met the precision requirement of the standard method. With its advantages of better repeatability, fast, easy operation, the new method can be used as an alternative for the determination of wax content, softening point and penetration of bitumen.
RESUMO
ABSTRACT: The efficacy of acupuncture in treating pain diseases has been recognized in clinical practice, and its mechanism of action has been a hot topic in academic acupuncture research. Previous basic research on acupuncture analgesia has focused mostly on the nervous system, with few studies addressing the immune system as a potential pathway of acupuncture analgesia. In this study, we investigated the effect of electroacupuncture (EA) on the ß-endorphins (ß-END) content, END-containing leukocyte type and number, sympathetic neurotransmitter norepinephrine (NE), and chemokine gene expression in inflamed tissues. To induce inflammatory pain, about 200 µL of complete Frester adjuvant (CFA) was injected into the unilateral medial femoral muscle of adult Wistar rats. Electroacupuncture treatment was performed for 3 days beginning on day 4 after CFA injection, with parameters of 2/100 Hz, 2 mA, and 30 minutes per treatment. The weight-bearing experiment and enzyme-linked immunosorbent assay showed that EA treatment significantly relieved spontaneous pain-like behaviors and increased the level of ß-END in inflamed tissue. Injection of anti-END antibody in inflamed tissue blocked this analgesic effect. Flow cytometry and immunofluorescence staining revealed that the EA-induced increase in ß-END was derived from opioid-containing ICAM-1 + /CD11b + immune cells in inflamed tissue. In addition, EA treatment increased the NE content and expression of ß2 adrenergic receptor (ADR-ß2) in inflammatory tissues and upregulated Cxcl1 and Cxcl6 gene expression levels. These findings provide new evidence for the peripheral analgesic effect of acupuncture treatment by recruiting ß-END-containing ICAM-1 + /CD11b + immune cells and increasing the ß-END content at the site of inflammation.