RESUMO
To investigate the whole-reach nitrate (NO3--N) uptake dynamics in a headwater agricultural stream, we performed five pulse tracer additions of a reactive solute (as KNO3) and a conservative solute (as NaBr) in an agricultural drainage ditch in Hefei district, Chaohu Lake basin, from October 2016 to April 2017. The TASCC (tracer additions for spiraling curve characterization) approach and Michaelis-Menten (M-M) method were applied for the simulation of NO3--N uptake dynamics. Results showed that the ambient areal rate of total NO3--N uptake Uamb varied from 11.40 to 69.13 µg ·(m2 ·s)-1 with an average of 34.45 µg ·(m2 ·s)-1, and the ambient uptake velocity Vf-amb averaged 0.24 mm ·s-1 and varied from 0.07 to 0.43 mm ·s-1 across three well-mixed sub-reaches in the study. The ambient uptake length Sw-amb averaged 199.06 m with a range from 92.51 to 405.74 m, which was much smaller than the length of the drainage ditch (about 2.5 km), suggesting that the agricultural drainage ditch had a high potential for NO3--N retention. Generally, the M-M model fit the NO3--N uptake dynamics well, and the maximum uptake Umax ranged from 158 to 1280 µg ·(m2 ·s)-1 with a mean of 631.13 µg ·(m2 ·s)-1. The half saturation constant Km ranged from 0.16 to 5.52 mg ·L-1 with a mean of 1.46 mg ·L-1. According to correlation analysis, Sw-amb was negatively correlated with NO3--Namb, and Uambwas significantly positively correlated with NO3--Namb, while other nutrient spiraling metrics were not correlated with the NO3--N ambient concentration. Hydrological conditions had no distinct effect on the NO3--N retention, but both the width variability Фw and variability in cross-sectional area ФA were significantly correlated with most of the nutrient spiraling metrics, indicating that geomorphic features in the drainage ditch evidently impacted NO3--N uptake.
RESUMO
<p><b>OBJECTIVE</b>To observe the intervention effect of Leihong Granule (LG) in in-stent restenosis (ISR) after endovascular therapy for lower extremity arterial occlusive diseases (LEAOD).</p><p><b>METHODS</b>Recruited 80 LEAOD patients who successfully underwent endovascular therapy (balloon dilation and stent implantation) were randomly assigned to two groups, the control group and the LG group, 40 in each group. Patients in the control group received basic treatment, while those in the LG group additionally took LG for 3 months. Plasma levels of IL-10, IL-18, CRP, and the intima-media thickness (IMT) of lower extremity artery were observed in the two groups between and after treatment. The rate of stent patency, ABI, intermittent claudication, rest pain, and the incidence of amputation the two groups were recorded and observed in the two groups.</p><p><b>RESULTS</b>In the control group, serum levels of IL-10, IL-18, CRP, and IMT were significantly higher one month after surgery than before surgery (P < 0.05). There was no significant difference in serum levels of IL-10, IL-18, CRP, or IMT between the two groups before surgery (P > 0.05). These indices were obviously lower in the LG group than in the control group after surgery (P < 0.05). Compared with the control group, the incidence rates of intermittent claudication and the rest pain at 6 months and 12 months after surgery significantly decreased (P < 0.05). The stent patency rate at 6 months and 12 months after surgery, and ABI were significantly higher than those of the control group (P < 0.05). There was no statistical difference in the amputation rate between the two groups (P > 0.05).</p><p><b>CONCLUSION</b>LG might effectively improve ischemic symptoms of affected limbs possibly through lowering the ISR rate after endovascular therapy for LEAOD through preventing immunosuppressive actions.</p>