Asymmetric expression of CA2 and CA13 linked to calcification in the bilateral mandibular condyles cause crossed beaks in chickens

Crossed beak is a complex mode of inheritance with prevalence ranging from 0.2 to 7.4% in at least 12 chicken strains worldwide.To reveal the intrinsic factors causing crossed beaks,genes expression patterns in bilateral mandibular condyle between affected and normal birds were characterized by RNA sequencing analysis in the present studies.Crossed beak was induced by short length of unilateral mandibular ramus,and a total of 110differentially expressed genes were up-or down-regulated in the affected(short)mandibular condyle side as compared to the normal side.Carbonic anhydrase 2(CA2)and Carbonic anhydrase 13(CA13)were enriched in the carbonate dehydratase activity,and high-expressed in mandibular condyle and osteoblasts(P<0.05).However,both were low-expressed in short mandibular condyle side of affected birds(P<0.05).The carbonate dehydratase inhibitor experiments confirmed that there is positive association between the calcification and carbonic anhydrase isoenzymes.Quantitative analysis with cetylpyridinium chloride showed a decrease in calcification when the cells were transfected with an anti-CA13 shRNA.Our research suggested that CA2 and CA13 are down-calcified in shortside mandibular condyle,and caused mandibular ramus to grow slowly.CA2 and CA13 have the critical role in crossed beaks by regulating calcification of mandibular condyle.

Monochromatic green light stimulation during incubation shortened the hatching time via pineal function in White Leghorn eggs

Background:Effect of monochromatic green light illumination on embryo development has been reported in chickens.The avian pineal gland is an important photo-endocrine organ formed by a mediodorsal protrusion during embryonic development.However,the involvement of pineal gland in the light transduction process remains to be elucidated.In the present study,we investigated the influence of monochromatic green light on hatching time and explored the possible mechanism via pineal function.Results:A total of 600 eggs of White Leghorn(Shaver strain)were incubated under photoperiods of either 12 h of light and 12 h of darkness using monochromatic green light(12L:12D group)or 24 h of darkness(0L:24D group)for 18 d.Compared to 0L:24D group,the green light stimulation shortened the hatching time without extending the hatch window or impairing hatchability.The liver of embryos incubated in the 12L:12D light condition was heavier than those of the 0L:24D group on d 21 post incubation which may be linked to the observed increase in the serum concentration of insulin-like growth factor 1(IGF-1);primary secretion of the liver.Histological structure analysis of pineal gland demonstrated that the light stimulation increased follicle area,wall thickness and lumen area on d 10 and d 12 post incubation.Rhythmic function analysis demonstrated that three clock related genes(brain and muscle ARNT-like-1,BMAL1;circadian locomotor output cycles kaput,CLOCK;and cryptochrome-1,CRY1)and a melatonin rate-limiting enzyme related gene(arylalkylamine N-acetyltransferase,AANAT)were rhythmically expressed in the pineal gland of the 12L:12D group,but not in the 0L:24D group.Simultaneously,the light stimulation also increased the concentration of melatonin(MT),which was linked to hepatocyte proliferation and IGF-1 secretion in previous studies.Conclusions:The 12L:12D monochromatic green light stimulation during incubation shortened hatching time without impairing hatching performance.Pineal gland’s early histological development and maturation of its rhythmic function were accelerated by the light stimulation.It may be the key organ in the photo-endocrine axis that regulates embryo development,and the potential mechanism could be through enhanced secretion of MT in the 12L:12D group which promotes the secretion of IGF-1.

Model for seawater fouling and effects of temperature,flow velocity and surface free energy on seawater fouling

A kinetic model was proposed to predict the seawater fouling process in the seawater heat exchangers.The new model adopted an expression combining depositional and removal behaviors for seawater fouling based on the Kern–Seaton model.The present model parameters include the integrated kinetic rate of deposition(k d)and the integrated kinetic rate of removal(k r),which have clear physical signi ficance.A seawater-fouling monitoring device was established to validate the model.The experimental data were well fitted to the model,and the parameters were obtained in different conditions.SEM and EDX analyses were performed after the experiments,and the results show that the main components of seawater fouling are magnesium hydroxide and aluminum hydroxide.The effects of surface temperature,flow velocity and surface free energy were assessed by the model and the experimental data.The results indicate that the seawater fouling becomes aggravated as the surface temperature increased in a certain range,and the seawater fouling resistance reduced as the flow velocity of seawater increased.Furthermore,the effect of the surface free energy of metals was analyzed,showing that the lower surface free energy mitigates the seawater fouling accumulation.

Research progress on the divergence and genetic basis of agronomic traits in xian and geng rice

The Asian cultivated rice Oryza sativa can be classified into two major subspecies:japonica/geng and indica/xian.There are large physiological and phenotypic differences between the two subspecies,with each having its advantages and disadvantages.Understanding the differences between xian and geng could provide a foundation for cultivar improvement based on hybridization between subspecies in order to synthesize favorable traits.We review the origin and domestication of xian and geng rice,compare their differences in terms of physiological and phenotypical traits,and describe the molecular mechanism differences between the subspecies.Based on this knowledge,we propose an ideal plant architecture of geng rice varieties for northern regions.

Studies on Ecological Monitoring of Plant Community and Plant Diversity in Shenzhen, Southern China

From Jan. 2013 to Nov. 2018, we carried out the investigation on vegetation studies in the ecological monitoring programs, Shenzhen and totally researched 170 plant communities of mountain areas etc., few areas of street regions and parks etc., for communities’ structural characteristics and plant diversity. We comparatively analyzed natural forests, semi-natural forest and artificial forest composition and structural characters and family, genus and species diversity level and the main affected factors. We also researched and analyzed these communities’ structural characteristics and pant diversity, comparatively analyzed natural forests, semi-natural forest and artificial forest composition and structural characters and family, genus and species diversity level, the main affected factors;researched and analyzed the relationship between plant community structure characteristics with the absorbing ability to PM2.5 pollutants. The result showed that the structure and plant diversity of natural forest were obviously better than artificial disturbed forest or artificial forest, the semi-natural forest was the middle level of the forests, In the indices of height, DBH, coverage and crow width etc. of tree layer, natural forests and semi-natural forests were obvious higher than that of artificial disturbed forest or artificial forest;in some forests of artificial disturbed forest or artificial forest, though their richness indices of family and genus were a slightly higher, but this contribution was majorly due to herb layer plants, and some shrub layer plants. Analyzing three kinds of communities, the number of tree layer species of natural forest was the largest, and their every α-diversity index value was the highest;these characteristics values of semi-natural forest were second, artificial disturbed forests or artificial forests were the lowest;in shrub layer, and herb layer, few α-diversity indices of artificial disturbed forest or artificial forest were a slightly higher than that of some natural forests, but the integral values of the diversity indices of natural forest and semi-natural forest were obviously higher than the former. The research showed that in the artificial disturbed forest or artificial forest, because there have some little scale clearing areas, so some pioneer plant species could enter the community and formed a temporarily increase of species diversity, however, these species major were some shrub and herb plants;but tree layer possessed obviously more, even surpassed several ten times biomass than shrub and herb layers. Therefore, the respects of maintain ecosystem stability and other ecological efficient have major and dominated position and so on;and then this community can be natural recovery and succession, those forementioned new entire plants shall withdraw from the community and are replaced by the original plants of the community;but this process has already caused the ecological efficient loss and ecosystem unstable. Above research results are better evidence and theory reference to the argument problems on that are natural forest and natural restoration forest biodiversity higher? or is artificial forest biodiversity higher? and or is more artificial disturbed forest higher? Our researches showed that used random investigation method set quadrats, and combined typical investigation method, the structural indices in the all layer of community and all diversity indices of tree, shrub and herb layers and the integral values were similar, same or usually these indices in the community which set 600 m2, 800 m2 total quatrat area were higher (α-diversity) than that of more than 3000 m2, 4000 m2 or 7000 m2, even more than 17,000 m2 total quadrat area of communities. These lots of researches further proved that according to minimum area method for vegetation survey, in subtropical region, using random investigation method combined with typical investigation set 400 m2 or 400 m2 - 500 m2 total quad

19世纪英国医学界对黑人精神形象的塑造及其影响

近代英帝国的扩张及黑奴贸易活动使英国医学界有更多接触和研究黑人等“有色人种”的机会。基于18世纪后期逐步兴起的“多源论”,以及对黑人“生理缺陷”的初步认知,英国医学界在19世纪依据颅相学、气质学和人种病理学等一系列更具歧视性的“种族科学”,对黑人的“精神缺陷”和“精神疾病”进行了构建与研究。这不仅推动了“多源论”的进一步兴起,也衍生出一种具有种族主义色彩的文明观念,使得黑人等“有色人种”被塑造为在生理和精神上皆有“缺陷”的“不文明”的“低等种族”。此类认知迎合了近代西方殖民者固有的种族偏见及扩张需求,在19世纪中后期进一步催生出一种替西方殖民扩张辩护的“文明使命”论,为西方殖民者奴役和支配“有色人种”提供了重要的理论依据。

先天性心脏病患儿全身麻醉下口腔治疗的术前风险评估

先天性心脏病是儿科常见的先天性疾病之一,对全身麻醉的安全性存在潜在的影响,该类患儿围术期处理的难度远大于非先心病患儿。本文通过查阅文献,对该类患儿口腔治疗的术前风险评估与管理进行总结,表明先心病患儿围术期风险与先心病的种类和严重程度相关,术前须从症状、体征、辅助检查、心血管专科医师的建议等多方面综合考量。