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This study was conducted to determine the effects of feeding frequency on the growth, serum biochemical parameters, antioxidant status and hepatic growth hormone (GH), insulin-like growth factor I (IGF-I), lipoprotein lipase (LPL) and hepatic lipase (HL) gene expression levels of juvenile largemouth bass (Micropterus salmoides) reared in an in-pond raceway recirculating culture system (IPRS). Fish (initial body weight 5.0 ± 0.4 g) were hand-fed with a commercial diet under one of three different feeding frequency treatments (2, 3 or 4 meals/day) for 120 days. The results indicated that no significant differences were observed in the final body weight, weight gain and specific growth rate of fish fed different feeding frequencies on 30 days and 60 days (P > 0.05). Fish fed 2 times/day had higher growth than that fed 4 times/day on 90 days but had higher growth than those fed 3 and 4 times/day on 120 days. No significant differences were found in serum alanine aminotransferase (ALT), aspartate transaminase (AST), alkaline phosphatase (ALP) activities, total protein (TP), lysozyme and triglyceride (TG) content, hepatic total antioxidant capacity (T-AOC), glutathione peroxidase (GSH-PX) activities and malondialdehyde (MDA) content among fish fed different feeding frequency (P > 0.05). Serum glucose (Glu) content and catalase (CAT) activity decreased, while total cholesterol (TC) content increased with increasing feeding frequency. Fish fed 2 times/day had higher hepatic total superoxide dismutase (T-SOD) than that fed 4 times/day on 60 days, 90 days and 120 days (P

Supplemental Material, sj-pdf-1-ang-10.1177_00033197221082712 for Long-Term Blood Pressure Exposure From Childhood and Early Vascular Aging in Midlife: A 30-Year Prospective Cohort Study by Yu Yan, Yu Cao, Qiong Ma, Keke Wang, Yueyuan Liao, Yue Sun, Chen Chen, Jiawen Hu, Wenling Zheng, Chao Chu, Yang Wang, and Jianjun Mu in Angiology

The Chinese mitten crab, Eriocheir sinensis (H. Milne Edwards), is an important economic aquaculture species in China. It is very popular within Chinese consumers for the abundant nutrition and delicious taste. It has been widely cultured and had great yield recently; yet, the short available time of E. sinensis cannot satisfy consumers’ increasing demanding. Thus the overwintering cultivation of E. sinensis has become one problem to urgently await development. Aiming to find the optimal stocking density and time for overwintering rearing E. sinensis using net cages embedded in a circulating pond aquaculture system, in the present study, we analyzed the variations in growth performance, death rate, physiological status, and nutrient contents of E. sinensis at different stocking densities over time periods. The death rate increased significantly after rearing for 90 days, while medium stocking density had a slight advantage than other densities. Interestingly, E. sinensis had no significant weight loss during overwintering period regardless of stocking densities. Our findings suggested that the optimal stocking density is around 21.88 kg/m2 in case of overwintering cultivation less than 90 days; while a medium density of 15.63 kg/m2 is more suitable for longer term overwintering cultivation (more than 90 days). In any case, the optimal overwintering rearing of E. sinensis should not beyond the 2rd, April. We can barely found difference caused by stocking density in activity of digestive enzymes, antioxidant status, or gene expression of hsp70; however, their levels were fluctuant over rearing time. Moreover, we found no significant variation in muscular amino acids composition, but a rising ratio of PUFA/SFA, as well as increased levels of C20:4 and C20:5 in edible tissues after 105-days overwintering cultivation, suggesting an improved nutritional value and eating quality of E. sinensis. Our results provide a reference standard for the overwintering cultivation of E. sinensis. Keywords: Eriocheir sinensis, Stocking density, Cumulative survival rate, Fatty acids, Antioxidant status

Abstract oTo satisfy the requirement of large telescope, a large aperture focal plane shutte r with aperture size of 3 200mm was researched and designed to realize, which could be star ted and stopped in a relative short time with precise position, and also the blades could open and close at the same time at any orientation. Timing-belts and stepper motors were adopted as the drive mechanism. Velocity and position of the stepper motors were controlled by the PWM pulse generated by DSP. Exponential curve is applied to control the velocity of the stepper motors to make the shutter start and stop in a short time. The closing/open time of shutter is 0.2s, which meets the performance requirements of large telescope properly. Keywords olarge telescope; shutter; timing-belt, aperture size, closing/open time OMT12-OM100-18 1. INTRODUCTION With the requirement of a large telescope, a large aperture focal plane shutter which is mounted before the CCD is needed, while Camera exposure shutters with apertures in excess of 100 mm are hard to find on the ¯market °. Traditional shutters can be generally assorted to two categories by framework, lamina-type shutter and center-type shutter. The mechanism of lamina-type shutter is motor drive each lamina move by linkage mechanism, which is usually used in camera. The mechanism of center-type shutter is electromagnet control the movement of each blade by linkage mechanism ewhich is mostly used in telescope with small aperture. A ll kinds of shutters can't be simply enlarged with the similar framework. Shutter technology abroad leads us, their structure are complicated, and BONN shutter is famous among them, while the dimension can't satisfy our need. And most shutters abroad used in each large telescope are specifically designed according to different dimensional limitation and speed requirement. They are practically unavailable to our telescope. We have to design a shutter of the whole dimension less than 3 500mm and thinner than 20mm with aperture of 3 200mm, and the open/close time less than 0.2s.