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21.
Warm or cool ambient temperatures during winter generate plasticity in the within‐year timing of oviposition or breeding phenology shifts through the use of a reaction norm in many riverine ectotherms, but within‐year timing of oviposition in Hynobius kimurae (Caudata: Hynobiidae) is predicted to be constant at different water temperatures of a mountain stream. To clarify this difference, by experimentally controlling water temperatures from fall to spring and thus changing durations of aquatic hibernation and dates of oviposition, we determined whether oviposition is more advanced when water temperatures increase earlier than usual or is more delayed when water temperatures increase later than usual. Oviposition was more delayed than usual with earlier exposure to high water temperatures during spring and was earlier than usual with exposing to higher water temperatures during hibernation. Days from submergence to oviposition were responsive to cumulative daily water temperatures from submergence to oviposition within a population. A rate of increase in days from submergence to oviposition was different between populations but was constant within a population even if minimal water temperatures varied each year. When running a program of a Markov chain Monte Carlo generalized linear mixed model for Bayesian computation to interpret confounding effects, neither different treatments nor different years statistically affected days from submergence to oviposition. These results suggest that a biological clock exits for days from submergence to oviposition in H. kimurae, which could allow survival in situations with either warmer or cooler environments. 相似文献
22.
研究盐渍榨菜在流通过程中环境因素:流通温度、流通湿度、光照强度、流通时间作用下的品质变化规律,采用响应面法得出各因素对盐渍榨菜品质影响,并确定相应的数学模型,从而得出影响因素与榨菜品质变化的关系. 相似文献
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Rana Mustafa Yue He Youn Young Shim Martin J. T. Reaney 《International Journal of Food Science & Technology》2018,53(10):2247-2255
Aquafaba, the viscous liquid resulting from cooking chickpeas in water is typically discarded. However, this solution is now widely used by the vegan community as an egg replacement that adds texture to food products, such as mayonnaise, pudding, ice cream and baked goods. Sponge cake was prepared with either egg white or aquafaba derived from ten different brands of canned chickpea and the texture and colour were compared. Aquafaba obtained from each chickpea can produced foam which differed in both properties and stability. In addition, aquafaba from some brands provided comparable foam volume and stability to that achieved with egg white. The colour and texture of sponge cake made with either egg white or aquafaba were similar and acceptable, but cakes prepared with aquafaba were less springy, and less cohesive than cake that included egg white. Based on our results, it appears that aquafaba has potential to replace egg white in eggless cake recipes. 相似文献
26.
Dental caries is a highly prevalent disease caused by colonisation of tooth surfaces by cariogenic bacteria, such as Streptococcus sobrinus and Streptococcus salivarius. Reducing initial adherence of such bacteria to teeth may delay onset of caries. Many foods, such as milk, can inhibit microbial adherence. In this investigation, the effect of untreated (UT) and enzyme-treated (ET) dairy powders on adherence of S. sobrinus and S. salivarius to hydroxylapatite (HA), an analogue of tooth enamel, was examined. Untreated (UT) acid whey protein concentrate (AWPC) 80 inhibited streptococcal adherence to phosphate-buffered saline-coated HA (PBS-HA) and saliva-coated HA (S-HA) by >80% at ?31.25 μg mL−1. UT sweet WPC80, buttermilk powder and cream powder also significantly reduced adherence (P < 0.05). Enzyme-treatment of all dairy powders reduced their anti-adhesion activity. However, ET sweet WPC80 significantly inhibited growth of these streptococci (P < 0.05) at ?0.6 mg mL−1. Therefore, dairy powders may reduce progression of dental caries by their anti-adhesion and/or antibacterial activity. 相似文献
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REFLICS: Real-time flow imaging and classification system 总被引:1,自引:0,他引:1
Sadahiro Iwamoto David M. Checkley Jr. Mohan M. Trivedi 《Machine Vision and Applications》2001,13(1):1-13
An accurate analysis of a large dynamic system like our oceans requires spatially fine and temporally matched data collection
methods. Current methods to estimate fish stock size from pelagic (marine) fish egg abundance by using ships to take point
samples of fish eggs have large margins of error due to spatial and temporal undersampling. The real-time flow imaging and
classification system (REFLICS) enhances fish egg sampling by obtaining continuous, accurate information on fish egg abundance
as the ship cruises along in the area of interest. REFLICS images the dynamic flow with a progressive-scan area camera (60
frames/s) and a synchronized strobe in backlighting configuration. Digitization and processing occur on a dual-processor Pentium
II PC and a pipeline-based image-processing board. REFLICS uses a segmentation algorithm to locate fish-egg-like objects in
the image and then a classifier to determine fish egg, species, and development stage (age). We present an integrated system
design of REFLICS and performance results. REFLICS can perform in real time (60 Hz), classify fish eggs with low false negative
rates on real data collected from a cruise, and work in harsh conditions aboard ships at sea. REFLICS enables cost-effective,
real-time assessment of pelagic fish eggs for research and management.
Received: 12 April 2000 / Accepted: 6 July 2000 相似文献
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用结英期蚕豆苗(荚果可供采青豆食用)植株上30厘米左右之嫩梢制作的叶蛋白饲料,适口性良好.用4%的蚕豆苗叶蛋白饲料等量取代产蛋鸡饲粮中的鱼粉(1.5%)和焙炒大豆(2.5%)时,对产蛋鸡的生产性能无明显影响(P>0.05),但极显著地改善了蛋黄色泽等级(P<0.01)、降低了软破蛋率,从而显著地改善了鸡蛋品质,提高了养鸡经济效益. 相似文献
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在螳螂孵化前,调查了螳螂卵囊在柞蚕场中的水平分布格局。经卡平方检验和5种聚集指标的测定结果表明,螳螂卵囊的空间分布型属于聚集分布中的负二项分布,即在柞林间的分布特点表现为极不均匀的嵌纹分布,种群中个体在发生概率上是不相同的,样方内一个个的存在,增加了同样方内其他个体发生的概率。 相似文献