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1.
This paper asks whether the technological development of a nation reduces the inter‐regional hierarchy in knowledge flow. We examine two scenarios that are the alternative to each other. The first is what we call the globalization of regional innovation system/weakening of inter‐regional hierarchy scenario: As many regions develop their niches in the global economy, the national “anchor” region loses its relative importance as the importer and distributor of new knowledge, rendering the domestic inter‐regional hierarchy less significant as a result. The second scenario is the globalization of national innovation system/persistence of inter‐regional hierarchy. The nation’s traditional anchor region becomes even more active in importing technology and distributing it to other regions of the country. To test which scenario is closer to reality, we employ social network metrics to analyse inter‐regional technology diffusion networks using Chinese patent licensing data for the 1998–2013 period. Our findings support the second scenario, showing that the influence of the traditional anchor region persists in the hierarchical network structure as new cities enter the network. We found five anchor regions: the three usual suspects—Beijing, Shanghai and Shenzhen—plus two that were slightly less expected—Dongguan and Suzhou.  相似文献   
2.
The medical records of 23 dogs that underwent medial canthoplasty for treatment of epiphora were reviewed. The most prevalent breed encountered was the shih tzu. Other affected breeds included the Pekingese, Maltese, toy poodle, and pug. All dogs had epiphora associated with medial canthal trichiasis and/or entropion. Other ocular abnormalities included conjunctivitis, keratitis, pigmentary keratitis, corneal ulceration, globe prolapse, and nasal fold trichiasis. After medial canthoplasty, the epiphora resolved in all dogs.  相似文献   
3.
This study investigated the effect of dietary nutmeg oil (NO) on growth performance, blood parameters, lipid peroxidation and heat shock protein (HSP) 70 expression in Korean native chicken (KNC) reared under hot temperature. We allocated 273 meat‐type KNCs (Hanhyup3, 4‐week‐old, body weight [BW] = 539.93 ± 1.75 g) to the following three treatments with seven replicate pens (13 birds/pen) per treatment. Three treatment diets were as follows: (a) Control, basal diet without NO supplementation; (b) NO 250; and (c) NO 500, basal diet supplemented with 250 and 500 ppm NO respectively. Diets and water were provided ad libitum throughout the 6‐week feeding trial. During overall period (0–6 weeks), no differences (p > 0.05) were observed in BW gain (BWG), feed intake (FI) and feed conversion rate (FCR) among treatments. However, the FI at 0–3 weeks decreased (p < 0.05) quadratically with increasing NO levels. Most blood parameters did not differ (p > 0.05) among treatments, although the monocyte level of the NO 500 group was considerably lower (p > 0.05) than that of the other groups. Furthermore, dietary NO did not affect serum triglyceride, cholesterol, total protein, albumin, calcium, phosphorus and alanine aminotransferase (ALT) levels (p > 0.05); however, it linearly decreased serum aspartate aminotransferase (AST) level (p < 0.05). Additionally, serum malondialdehyde (MDA) concentration decreased (p < 0.05) and heart MDA concentration was lower (p = 0.08) with increasing dietary NO supplementation. After a 3‐hr heat (35°C) challenge, the rectal temperature (RT) reduced (p < 0.05) linearly with increasing NO levels. Dietary NO did not affect liver HSP70 (p > 0.05) gene expression. In conclusion, NO potentially enhanced the ability of chickens to alleviate heat stress. Furthermore, our findings suggest that lipid oxidation inhibition by dietary NO likely mediated the enhanced heat‐stress tolerance of the chickens.  相似文献   
4.
This study was performed to evaluate the effects of conditioned media (CM) from human amniotic epithelial cells (HAECs) on the corneal wound healing process. Eighteen rabbits (36 eyes) were used and randomly assigned to three groups according treatment: CM from HAECs (group 1), vehicle alone (group 2), and saline (group 3). Corneal alkali injuries were induced with 1 N sodium hydroxide. Each reagent used for treatment evaluation was injected into the dorsal bulbar subconjunctiva and the area of the corneal epithelial defect was measured every other day. Two animals from each group were euthanized at a time on days 3, 7, and 15, and the cornea was removed for histological examination. The sum of the epithelial defect areas measured on day 0 to day 6 as well as day 0 to day 14 in group 1 was significantly smaller than those of other groups. Histological examination revealed that the group 1 corneas had less inflammatory cell infiltration and showed more intact epithelial features compared to the other groups. These results suggest that CM from HAECs promote corneal wound healing in rabbits.  相似文献   
5.
Kim  Do-Hoon  Seo  Ju-Nam  Kim  Hyung-Seok  Lee  Kyounghoon 《Fisheries Science》2012,78(3):743-751
In this study, changes in total factor productivity of 12 Korean offshore fisheries between 1997 and 2009 were estimated through the Malmquist productivity index, which is a nonparametric method. Also, the cause of such changes in productivity of each fishery was analyzed more specifically by segmenting into factors for technological progress and technical efficiency. As a result of this analysis, the total factor productivity change of the entire offshore fisheries was −6.0 %. Changes in the technical efficiency and technological level factors, respectively, contributed 0.2 and −6.2 % to this rate of decrease in total factor productivity; that is, inactivity of technological progress led to the decrease in productivity of the offshore fisheries. In addition, technological progress and technical efficiency were found to differently influence the change in total factor productivity of each fishery. In order for each fishery to improve productivity, better rational fisheries management policies by the government and efforts by the fishing industry and individual fishing business units must accompany factors that promote productivity increase.  相似文献   
6.

Purpose

Sulfamethazine (SMT) is increasingly detected in environmental matrices due to its versatile use as antibiotics. We aimed to investigate the benefits and roles of steam activation of biochars with respect to SMT sorption kinetics and equilibrium sorption.

Materials and methods

Biochars were produced from burcucumber plant and tea waste using a pyrolyzer at a temperature of 700 °C for 2 h. The biochar samples were treated with 5 mL min?1 of steam for an additional 45 min for post-synthesis steam activation. The SMT sorption on the unmodified and steam activated biochars were compared.

Results and discussion

The time taken to reach equilibrium was significantly less for steam activated biochars (~4 h) than non-activated biochars (>24 h). Up to 98 % of SMT could be removed from aqueous solutions by steam activated biochars. The sorption kinetic behaviors were well described by the pseudo-second model and SMT sorption rates of steam activated biochars (k 2?~?1.11–1.57 mg g?1 min?1) were significantly higher than that of the unmodified biochars (k 2?~?0.04–0.11 mg g?1 min?1) because of increased availability of accessible porous structure with averagely larger pore diameters. Moreover, the equilibrium sorption on the unmodified biochars was significantly influenced by increasing solution pH (~30–50 % reduction) because of speciation change of SMT, whereas steam activated biochars manifested much stronger sorption resilience against pH variation (~2–4 % reduction only) because the enhanced porosity offset the effect of unfavorable electrostatic repulsion.

Conclusions

The observed features of steam activated biochars would render their applications more versatile and reliable in field throughout changeable environmental conditions.
  相似文献   
7.
To determine the immune responses in pigs to hog cholera virus after treatment with an ionized alkali mineral complex (IAMC), 40 healthy pigs (28-32 days old) from a commercial swine farm were purchased and housed into 4 groups (n=10 each). All pigs were vaccinated intramuscularly (1 ml) with an attenuated live hog cholera virus (HCV, LOM strain) at 28-32 days old and challenged with a virulent hog cholera virus at 8 weeks after vaccination. Each group was treated with PowerFeel sprayed diet as 0.05% (w/w) in a final concentration (T-1, n=10), a diet mixed with SuperFeed as 3% (w/w) in a final concentration (T-2, n=10), or a diluted PowerFeel solution (1:500, v/v) as drinking water (T-3, n=10), respectively. A group (n=10) served as a non-treated control. Proportions of expressing CD2+ and CD8+ cells increased significantly (p<, 0.05) at 8-week post-application. Mean antibody titers of each group against HCV gradually increased to higher levels after vaccination and with challenge of the virulent virus. In conclusion, the IAMC-treated diets can be helpful for the improvement of growth in pigs with proper vaccination program, while the IAMC-treated diets have no effects on the clinical protection against hog cholera.  相似文献   
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10.
An 8-week feeding experiment was conducted to investigate the effects of different dietary macronutrient level and feeding frequency on the growth, feed utilization, and body composition of juvenile rockfish. Triplicate groups of fish (body weight of 4.1 g) were fed the experimental diets containing either high levels of carbohydrate (HC, 35%), lipid (HL, 13%), or protein (HP, 55%) at different feeding frequencies (twice daily, once daily, and once every 2 days). Weight gain was affected by feeding frequency but not by dietary composition. Weight gain of fish fed the diets once every 2 days was significantly (P < 0.05) lower than that of other groups. Daily feed intake and energy intake were affected by both dietary composition and feeding frequency. Daily feed intake of fish fed the HC diet was significantly (P < 0.05) higher than that of fish fed the HL and HP diets at the same feeding frequency. Feed efficiency and protein efficiency ratio were affected by both dietary composition and feeding frequency and decreased with increasing feeding frequency in the same dietary composition. Feed efficiency and protein efficiency ratio of fish fed the HC diet were significantly (P < 0.05) lower than those of fish fed the HL diet at the same feeding frequency. Whole-body lipid content of fish fed the HL diet was significantly (P < 0.05) higher than that of fish fed the HC and HP diets at the same feeding frequency. These results indicate that an increase of dietary lipid level compared with dietary carbohydrate level may have the advantage of a protein-sparing effect at same feeding frequency, and a once-daily feeding regime is more effective than twice daily or one feeding every 2 days to improve growth performance of juvenile rockfish grown from 4 to 21 g.  相似文献   
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