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1.
This study investigated how urban cultural and economic tolerance affects urban innovative capacities based on China's prefecture‐level cities. Several tolerance indices, including ratios of migrants, rental housing, gay people, and private economies were introduced and the cities’ tolerance scores were measured using factor analysis. The results show that cities with higher cultural and economical tolerant scores were agglomerated in three metropolitan areas in China's southeastern coastal region. The spatial regression model demonstrates that urban cultural and economic tolerance increases urban innovation output and promotes innovation capacities. We also introduced the crime rate as an instrumental variable and found that the effect of tolerance on innovation remains robust. Our study suggests it is important for the Chinese government to establish an open and tolerant environment to attract migrants, creative artists, and entrepreneurs to foster urban vitality and improve urban innovative capacities.  相似文献   
2.
角质蜡质是植物在长期的生态适应过程中进化形成的一类次生代谢产物,广泛参与了植物抗逆、抵御病虫害侵染等诸多抗性生理过程。角质蜡质在植物-病原互作中发挥了重要作用,是植物抗病机制的重要组成部分。随着分子生物学的发展,人们对植物角质蜡质代谢及其抗病机理的认知不断深入。本研究综述了植物角质蜡质生物合成与其抗病机理的最新研究进展并对未来研究提出展望。目前,植物角质蜡质的抗性机理研究主要集中于组成型抗性和诱导型抗性2类。角质蜡质作为角质层主要成分,一方面可作为组成型抗性成分发挥物理抗性(物理屏障)和化学抗性(抑菌)作用;另一方面,也可作为诱导型抗性成分发挥作用,诱导产生的角质蜡质单体除了作为角质层主要成分发挥物理抗性外,也可作为信号分子或者诱导子激活下游的抗性反应进而发挥其化学抗性功能。未来可侧重于对角质蜡质诱导抗性机理的深入阐释,进一步丰富植物化学生态学研究理论体系。此外,基于角质蜡质的诱导抗性作用,可开发角质蜡质类生物农药(植物免疫诱导剂),为植物病害防控提供新思路。图1参71  相似文献   
3.
Conflicting information has been published regarding the cause of a valentine‐shaped cardiac silhouette in dorsoventral or ventrodorsal thoracic radiographs in cats. The purpose of this retrospective, cross‐sectional study was to test the hypothesis that the valentine shape is primarily due to left atrial enlargement. Images for cats with a radiographic valentine‐shaped cardiac silhouette and full echocardiography examination were retrieved and independently reviewed. A subjective scoring system was used to record severity of radiographic valentine shape. Subjective radiographic evidence of left atrial enlargement in a radiographic lateral projection and a final diagnosis based on medical records were also recorded. A total of 81 cats met inclusion criteria. There was a strong positive correlation (P < 0.001) between echocardiographic left atrial size and severity of radiographic valentine shape. There was no effect of echocardiographic right atrial size on the severity of valentine shape, except when concurrent with severe left atrial enlargement. In this situation, right atrial enlargement increased the likelihood of observing a severe valentine shape. There was no effect of right atrial enlargement on the shape of the cardiac silhouette when left atrial enlargement was absent or only mild to moderate. There was no correlation between the category of final diagnosis of cardiac disease and the severity of valentine shape. Findings from this study supported the hypothesis that a valentine‐shaped cardiac silhouette in radiographs is due primarily to left atrial enlargement in cats, with right atrial enlargement only impacting the shape if concurrent with severe left atrial enlargement.  相似文献   
4.

Background

Hereditary ataxias with similar phenotypes were reported in the Smooth-Haired Fox Terrier, the Jack Russell Terrier and the Parson Russell Terrier. However, segregation analyses showed differing inheritance modes in these breeds. Recently, molecular genetic studies on the Russell group of terriers found independent mutations in KCNJ10 and CAPN1, each associated with a specific clinical subtype of inherited ataxia. The aim of this study was to clarify whether or not Smooth-Haired Fox Terriers with hereditary ataxia and dogs of other related breeds harbor either of the same mutations. A sub goal was to update the results of KCNJ10 genotyping in Russell group terriers.

Findings

Three Smooth-Haired Fox Terriers with hereditary ataxia and two Toy Fox Terriers with a similar phenotype were all homozygous for the KCNJ10 mutation. The same mutation was also found in a heterozygous state in clinically unaffected Tenterfield Terriers (n = 5) and, in agreement with previous studies, in Jack Russell Terriers, Parson Russell Terriers, and Russell Terriers.

Conclusions

A KCNJ10 mutation, previously associated with an autosomal recessive spinocerebellar ataxia in Jack Russell Terriers, Parson Russell Terriers, and Russell Terriers segregates in at least three more breeds descended from British hunting terriers. Ataxic members of two of these breeds, the Smooth-Haired Fox Terrier and the Toy Fox Terrier, were homozygous for the mutation, strengthening the likelihood that this genetic defect is indeed the causative mutation for the disease known as “hereditary ataxia” in Fox Terriers and “spinocerebellar ataxia with myokymia, seizures or both” in the Russell group of terriers.  相似文献   
5.
6.
Genome-wide association studies (GWAS) are useful to facilitate crop improvement via enhanced knowledge of marker-trait associations (MTA). A GWAS for grain yield (GY), yield components, and agronomic traits was conducted using a diverse panel of 239 soft red winter wheat (Triticum aestivum) genotypes evaluated across two growing seasons and eight site-years. Analysis of variance showed significant environment, genotype, and genotype-by-environment effects for GY and yield components. Narrow sense heritability of GY (h 2  = 0.48) was moderate compared to other traits including plant height (h 2  = 0.81) and kernel weight (h 2  = 0.77). There were 112 significant MTA (p < 0.0005) detected for eight measured traits using compressed mixed linear models and 5715 single nucleotide polymorphism markers. MTA for GY and agronomic traits coincided with previously reported QTL for winter and spring wheat. Highly significant MTA for GY showed an overall negative allelic effect for the minor allele, indicating selection against these alleles by breeders. Markers associated with multiple traits observed on chromosomes 1A, 2D, 3B, and 4B with positive minor effects serve as potential targets for marker assisted breeding to select for improvement of GY and related traits. Following marker validation, these multi-trait loci have the potential to be utilized for MAS to improve GY and adaptation of soft red winter wheat.  相似文献   
7.
Knowledge of the movement and habitat use of fishes is important in identifying and understanding the causes of population declines and predicting how populations are likely to respond to management interventions. In this study, radiotelemetry was used to examine the spring and summer movement and habitat use patterns of the freshwater catfish (Tandanus tandanus) in a remnant wetland to inform the development of recovery actions for this threatened species. Twenty‐one adult fish were tagged and released within Tahbilk Lagoon, Victoria, Australia, in September 2009. Fish were located every 1–2 weeks between September 2009 and February 2010, a period which coincides with the spawning period for the species. Eleven of the fish were also tracked every 2 h for 68 consecutive hours in December 2009 to examine diel movements. The study revealed that freshwater catfish make extensive use of cover (e.g. wood and macrophytes) and typically have limited ranges (median total linear range and 90% linear range 599 and 173 m respectively), although they occasionally moved more extensively (up to 1.5 km) between floodplain and riverine habitats. Fish moved over much greater areas at night compared with during the day. There was also evidence of sex‐specific variation in movement, with a trend for greater movement of female fish at night compared with males. The results of the study suggest that strategies that protect macrophyte and wood habitats and improve connectivity between riverine and floodplain habitats are likely to be important in maintaining and restoring remnant populations of this species.  相似文献   
8.
9.
Effects of harvest moisture and bale wrapping on forage quality and mold formation in orchardgrass (Dactylis glomerata L.) hay have not been investigated. The objectives of this study were to determine the effects of initial bale moisture and plastic wrapping on temperature, forage quality (protein, fiber components, and digestible energy), and mold formation in large round-baled orchardgrass hay. In all, 40 round bales of mature orchardgrass hay measuring 1.2 × 1.5 m2 were baled at three different moisture ranges (eight bales per treatment): 124 to 166 g/kg (low moisture); 180 to 232 g/kg (intermediate moisture); and 259 to 337 g/kg (high moisture). Selected bales within each moisture range were individually wrapped in plastic (16 bales), and temperature sensors were placed in each bale for up to 10 weeks. The lowest (P ≤ .01) maximum temperature and heating degree-day accumulations were observed when initial bale moisture content was 124 g/kg or when hay was wrapped, regardless of initial moisture content. In 2008 and 2009, all wrapped hays resulted in similar forage quality (P ≤ .14) and mold counts (P = .94) compared with 124 g/kg moisture hay. Hay baled at 166 g/kg resulted in fiber (P ≥ .82) and mold (P = .21) components similar to higher moisture bales. Mold counts for hay baled at 166 g/kg and 124 g/kg moisture were 24.8 × 106 and 2.7 × 104 CFU/g, respectively, demonstrating that large round bales are prone to molding at relatively low moisture concentrations. Maintenance of forage quality and reduction in mold growth were achieved by baling dry (124 g/kg moisture) or wrapping round bales of orchardgrass hay up to 337 g/kg moisture.  相似文献   
10.
Summary Incense cedar heartwood infected by the pocket rot fungus Polyporus amarus was subjected to microtensile testing and miscroscopical examination to determine effects of this fungus upon wood substance adjacent to advanced decay pockets. Although springwood of the annual ring nearest the decay pocket in some samples had a slightly lower tensile strength than springwood from the same ring but a distance from the pocket, the difference was not statistically significant. Microscopical examination revealed the presence of small, sparse bore holes and hyphae in approximately the same number inside and outside the advanced decay pockets, and in discolored regions of incipient decay. A few bore holes and hyphae were found in specimens from what was macroscopically considered to be sound wood. Polarized illumination revealed no evidence of diffusion of cellulolytic enzymes from the hyphae in regions other than within advanced decay pockets, but the small numbers of hyphae and bore holes observed in decay pockets indicated that considerable enzyme diffusion might be necessary for decay to procede. The data suggest that possible alteration of physical, mechanical, and chemical properties in wood substance surrounding decay pockets need not be a significant factor for consideration in utilization of pecky incense cedar.
Zusammenfassung Kernholz von Zeder (Libocedrus decurrens), das von Polyporus amarus befallen worden war, wurde Mikro-Zugfestigkeitsprüfungen und einer mikroskopischen Durchmusterung unterworfen. Es sollten die Auswirkungen dieses Pilzbefalles auf jene Teile der Holzsubstanz geprüft werden, die unmittelbar an die Befallsstellen angrenzen. Das Frühholz eines Jahrringes, das einer Befallsstelle am nächsten lag, zeigte zwar bei einigen Proben eine geringfügig niedrigere Zugfestigkeit als das Frühholz desselben Jahrringes, das aber von der Befallsstelle weiter entfernt lag. Die Unterschiede waren jedoch statistisch nicht signifikant. Die mikroskopische Durchmusterung deckte das Vorhandensein von kleinen, etwas zerstreut liegenden Bohrlöchern und Hyphen auf, in etwa gleichgroßer Anzahl innerhalb und außerhalb der Stellen fortgeschrittenen Befalls und in den verfärbten Bereichen des beginnenden Befalls. Einige wenige Bohrlöcher und Hyphen wurden ferner in Proben festgetsellt, die bei makroskopischer Betrachtung gesund erschienen. Im polarisierten Licht ließ sich keine Diffusion von aus Hyphen stammenden celluloitischen Enzymen außerhalb der Befallsbereiche beobachten. Die wenigen Hyphen und Bohrlöcher, die in den Befallsstellen beobachtet werden konnten, gaben aber einen Hinweis darauf, daß bei der Ausbreitung eine beträchtliche Enzymdiffusion stattfinden muß. Die ermittelten Werte weisen darauf hin, daß die möglicherweise eintretende Änderung der physikalischen, mechanischen und chemischen Eigenschaften des Holzes in unmittelbarer Umgebung der Befallsstellen als wichtige Faktoren bei der Verarbeitung dieses Holzes beachtet werden müssen.


Presented at the 1968 Forest Products Research Society Annual Meeting.  相似文献   
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