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Using texts from online blogs, this study aimed to analyze the effect of perceived characteristics of a place in the virtual space and their influence on its economic performance. Specifically, this study analyzed old retail space (traditional markets) in Seoul by empirically examining the relationship among the perceived characteristics, economic performances, and the physical and operative conditions of the markets’ facilities. The perceived characteristics by the bloggers were analyzed by the text-mining of the blog posts. Next, the associations among the multiple factors including the perceived characteristics, economic measures, were analyzed by PLS-SEM. Three types of characteristics were found from the texts: (a) value shopping, (b) novelty & food, and (c) affective sentiments. Among them, novelty & food have significant positive effects on annual sales growth and the vacancy reduction rates of the markets. The improved physical condition also had a positive direct effect on annual sales growth, which can be partially explained by its positive mediating effects on Novelty & Food. The operating condition had no significant relationship with the perceived characteristics but had significant effects on the four economic measures. The results imply that renovation projects could diminish certain characteristics of the space (i.e., affective sentiments), but it enhanced other place characteristics (i.e., food and novelty) following economic gains. 相似文献
3.
菜地不同施氮量下N2O逸出量的研究 总被引:11,自引:1,他引:11
用田间原位密闭气室法和乙炔抑制原状土柱培养法 ,研究了蔬菜地不同施氮量下 N2 O的逸出量。结果表明 ,在一定施氮量范围内 ,N2 O通量随施肥量的增加而上升 ;除最高施肥量 (N4 50 )外 ,N2 O占 (N2 +N2 O)的比率随施肥量的增加而增加。在施肥水平低时 ,氮素的损失以 N2 为主 ,当施肥量高于 30 0 kg/ hm2后 ,则以 N2 O为主。 2 m土体中 NO3- N分析结果表明 ,试验结束时对照和 N4 50 处理土壤剖面中有 NO3- N累积 ,其余各个处理氮素都存在一定程度的损失 ,其中损失量最大的是 N1 50 处理 ,与 N2 O逸出量的趋势相一致。 N2 O逸出量占肥料 N总用量的 0 .15 %~ 0 .6 6 % ,肥料逸出量占土壤 N2 O总逸出量的 39.0 %~ 70 .3% ,且在施氮水平低于 N30 0 以下时 ,N2 O逸出量有随施肥量增加而上升的趋势 相似文献
4.
Knut Wiik Vollset Randi Ingebjørg Krontveit Peder A Jansen Bengt Finstad Bjørn Torgeir Barlaup Ove Tommy Skilbrei Martin Krkošek Pål Romunstad Arnfinn Aunsmo Arne J Jensen Ian Dohoo 《Fish and Fisheries》2016,17(3):714-730
Parasites can, in theory, have large impacts on the survival of fish populations. One method to evaluate such impacts on anadromous species is to apply manipulative field experiments in which parallel groups of antiparasitically treated and non‐treated fish are simultaneously released and then subsequently recaptured as returning adults. A systematic review and meta‐analysis on all such Norwegian studies on Salmo salar provided a data set for the time period 1996 to 2011 on 118 release groups comprising 657 624 fish released and 3989 recaptured. The overall risk ratio (RR) was estimated to be 1.18 (95% CI: 1.07–1.30). The effect varied strongly between groups, (Higgins I2 = 40.1%). Over 70% of this heterogeneity could be explained by the release location, time period and baseline survival. The most important predictor variable was baseline survival. In groups with low recapture in the control group (low baseline survival), the effect of treatment was high (RR = 1.7), while in groups with high recapture in the control group (high baseline survival), there was no effect of treatment (RR ~ 1.00). The most prevalent parasite in the region affected by the drugs administered was Lepeophtheirus salmonis. Hence, the meta‐analysis supports the hypothesis that L. salmonis contributes to the mortality of S. salar during outward migration. However, the effect of treatment was not consistent, but was evidently strongly modulated by other risk factors. The results suggest that the population‐level effects of parasites cannot be estimated independently of other factors affecting the marine survival of S. salar. 相似文献
5.
Cytochrome P450 (CYP) 1A1 participates in the activation as well as detoxification of environmental pollutants such as aromatic
hydrocarbons. This CYP form is also efficiently induced by aromatic hydrocarbons. The presence of CYP 1A1 in the brain might
thus be of physiological and toxicological importance. In the present investigation on rainbow trout, the distribution of
7-ethoxyresorufin-O-deethylase (EROD) activity, a cytochrome CYP 1A1 catalyzed reaction, was measured in whole tissue homogenates
from brain parts. In control fish, a relatively high activity was found in the rainbow trout olfactory bulb compared to the
other brain parts. Although an EROD induction (3 to 7-fold) by β-naphthoflavone (BNF) was recorded in all brain parts from
the rainbow trout, the highest induced activity was measured in the olfactory bulbs. To ascertain the distribution of EROD
activity in cells, whole brain tissue was subfractionated by differential centrifugation. The fractionation scheme separated
mitochondria (P2 fraction) and microsomes (P3 fraction) as determined by marker enzymes and electron microscopy. In control
rainbow trout, a low EROD activity could be measured in the P2 fraction. BNF induced the EROD activity in both P2 and P3 fractions.
Western blotting showed the induction by BNF of a protein band in the P2 and P3 fractions with a molecular mass around 58,000
when highly specific anti-cod CYP 1A1 antibodies were used. ELISA measurements confirmed the induction of CYP 1A1 protein
in the rainbow trout brain subcellular fractions. 相似文献
6.
Molecular tracing confirms that infection with infectious pancreatic necrosis virus follows the smolt from hatchery to grow‐out farm 下载免费PDF全文
Anja B. Kristoffersen Magnus Devold Vidar Aspehaug Ove Gjelstenli Olav Breck Britt Bang Jensen 《Journal of fish diseases》2018,41(10):1601-1607
Infectious pancreatic necrosis (IPN) is an important restraint to production of salmonids in aquaculture globally. In order to implement efficacious mitigation strategies for control of this disease, it is important to understand infection routes under current production systems. IPN virus has been shown to be transmitted vertically in Rainbow trout, from broodstock to fingerlings in hatcheries, and there is circumstantial evidence suggesting that vertical transmission can also occur in Atlantic salmon, in addition to horizontal transmission between grow‐out fish in farms. In this study, we show that the smolt carries infection with IPN from hatchery to the marine farm. We do this by comparing sequences from fish groups taken both in hatcheries and on corresponding marine grow‐out farms. We use statistical analysis to prove that sequences obtained from the same fish group in both hatchery and marine farm are more similar than sequences obtained from random fish groups on hatcheries and marine farms. 相似文献
7.
Torben A. Bonde Tommy Nielsen Morten Miller Jan Sørensen 《Biology and Fertility of Soils》2001,34(3):179-184
Seasonal dynamics of in situ gross nitrogen (N) mineralization rates were measured using the 15N-NH4+ isotope dilution method in a Danish soil subjected to four different agricultural practices (set aside, barley, winter wheat and clover). Results were compared to arginine ammonification in the soil samples measured as NH4+ production following addition of excess (1 mM) arginine. In the set aside, barley, winter wheat and clover soils the average annual rates of gross N mineralization (0.29, 0.60, 1.34 and 1.75 µg NH4+-N g-1 day-1, respectively) and arginine ammonification activity (0.21, 0.55, 0.88, and 1.33 µg NH4+-N g-1 h-1, respectively) were well correlated. Furthermore, the seasonal variations of gross N mineralization and arginine ammonification activities were very similar, showing rapid responses to rainfall and generally higher activities in wetted soils. As tested in the laboratory, the arginine ammonification activity correlated well with heterotrophic microbial respiration activity (CO2 production) in soil samples and further displayed a simple, one-component Michaelis-Menten kinetics with a high affinity for arginine (Km value of 48 µM LJ µM) as determined from non-linear parameter estimation. This indicated that arginine ammonification activity was primarily due to microorganisms, and the activity was also shown to be at a minimum in sterile soil samples. All evidence thus supported that our standard assay of arginine ammonification activity provides a good index of gross N mineralization rates by the microorganisms in soil under in situ conditions. 相似文献
8.
Brantsaeter AL Haugen M Rasmussen SE Alexander J Samuelsen SO Meltzer HM 《Public health nutrition》2007,10(8):838-847
OBJECTIVE: To validate a new food-frequency questionnaire (FFQ) for measuring the intake of fruit, vegetables and tea reported by women participating in the Norwegian Mother and Child Cohort Study (MoBa). DESIGN: Intake of fruits, vegetables and tea estimated by the FFQ was compared with urinary flavonoid excretion, plasma carotenoid concentration and intake measured by a 4-day weighed food diary (FD). The triangular method was applied to calculate FFQ validity coefficients using two independent biomarkers. SETTING AND SUBJECTS: One hundred and nineteen women participating in MoBa. RESULTS: The FFQ estimate of fruit intake was significantly correlated with urine phloretin (r = 0.33), citrus fruit/juice with urine hesperetin (r = 0.44), cooked vegetables with plasma alpha-carotene (r = 0.37), and tea with urine kaempferol (r = 0.41) (P < 0.01 for all). On average, 60% of the participants fell into the same or adjacent quintiles when classified by FFQ and biomarkers. Significant correlations between the FFQ and FD were found for fruit (r = 0.39), vegetables (r = 0.34), juices (r = 0.50) and tea (r = 0.53). The FFQ validity coefficient was 0.65 for citrus fruit/juice and 0.59 for cooked vegetables as calculated by the triangular method. CONCLUSIONS: The validation study shows that the MoBa FFQ can be used to estimate fruit, juice, vegetable and tea intake in pregnant Norwegian women, and to rank individuals within the distribution. 相似文献
9.
Jiménez-Escrig A Dragsted LO Daneshvar B Pulido R Saura-Calixto F 《Journal of agricultural and food chemistry》2003,51(18):5540-5545
Artichoke (Cynara scolymus L.), an edible vegetable from the Mediterranean area, is a good source of natural antioxidants such as vitamin C, hydroxycinnamic acids, and flavones. The antioxidant activity of aqueous-organic extracts of artichoke were determined using three methods: (a) free radical 2,2-diphenyl-1-picrylhydrazyl (DPPH(*)) scavenging, (b) ferric-reducing antioxidant power (FRAP), and (c) inhibition of copper(II)-catalyzed in vitro human low-density lipoprotein (LDL) oxidation. In addition, the present study was performed to investigate the ability of the edible portion of artichoke to alter in vivo antioxidative defense in male rats using selected biomarkers of antioxidant status. One gram (dry matter) had a DPPH(*) activity and a FRAP value in vitro equivalent to those of 29.2 and 62.6 mg of vitamin C and to those of 77.9 and 159 mg of vitamin E, respectively. Artichoke extracts showed good efficiency in the inhibition in vitro of LDL oxidation. Neither ferric-reducing ability nor 2,2'-azinobis(3-ethylbenzothiazolin-6-sulfonate) radical scavenging activity was modified in the plasma of the artichoke group with respect to the control group. Among different antioxidant enzymes measured (superoxide dismutase, gluthatione peroxidase, gluthatione reductase, and catalase) in erythrocytes, only gluthatione peroxidase activity was elevated in the artichoke group compared to the control group. 2-Aminoadipic semialdehyde, a protein oxidation biomarker, was decreased in plasma proteins and hemoglobin in the artichoke-fed group versus the control group. In conclusion, the in vitro protective activity of artichoke was confirmed in a rat model. 相似文献
10.
Yevheniya Volchko Jenny Norrman Lars Rosèn Tommy Norberg 《Journal of Soils and Sediments》2014,14(11):1850-1860