Chorologische phänomene in Wasserpflanzengesellschaften Mitteleuropas

On the basis of three selected examples chorological phenomena in waterplant communities of central, east and southern Europe are represented. Species of the Atlantic-oceanic floral element of the order Juncetalia bulbosi, like Pilularia globulifera, Eleocharis multicaulis and Deschampsia setacea are growing in markedly secondary sites near their eastern border, i.e. in the Lusatian district of central Europe, especially in sand, gravel and clay pits as well as in residue lakes of opencast mines. As a result of intensive recent human activities numerous new sites are being established now causing an expansion of their distribution area. With decreasing oceanity from the central part to the eastern border of the area a change in the floristic-sociological structure of the relevant plant communities and in the hydrochemical composition of the respective water bodies takes place. In western Europe the species grow in soft water poor in minerals, in the eastern part (central Europe) in mineral-rich, hard water with calcium and sulphate.At present Ceratophyllum submersum has a high frequency in the northeastern area in Mecklenburg. The sites are morainic lakes (kettle holes) and small waters and ponds near settlements, which are enriched in minerals and nitrales in consequence of the intensive agricultural use of inorganic fertilizers. Moreover the waters are alkaline and rich in minerals, especially bicarbonate and possess a high range of total hardness. The example of eight different sites of Aldrovanda vesiculosa illustrates a striking change of its diagnostic value in its disjunct north-south distribution. In the northern part of central Europe Aldrovanda is found in the communities of the Utricularietea intermedio-minoris, both in waters with a low acidity rich in sulphate and in alkaline waters rich in bicarbonate (Sphagno-Utricularion and Scorpidio-Utricularion respectively). In southern central Europe and in southeastern Europe Aldrovanda occurs in Lemnetea and Potametea communities. In northeastern Poland Aldrovanda is found together with Hydrilla verticillata, Chara mentosa, Myriophyllum verticillatum and Scorpidium scorpioides.

Die Sippennomenklatur richtet sich nach Rothmaler et al. (1970).     

Synchronous Elicitation of Development in Root Caps Induces Transient Gene Expression Changes Common to Legume and Gymnosperm Species

Root cap development in cereals and legumes is self-regulated by a repressor that accumulates in the extracellular environment, and immersing the root tip into water results in renewed cap development. By exploiting this phenomenon, root cap mitosis and differentiation can be synchronously induced among populations. In Pisum sativum L., messenger RNA (mRNA) differential display revealed changes in expression of approximately 1% of the sample mRNA population within minutes of induced cap turnover. This profile changes sequentially over a period of 30 min, then stabilizes. Microarray analysis of Medicago truncatula root caps confirmed changes in expression of approximately 1% of the target population, within minutes. A cell specific marker for cap turnover exhibited the same temporal and spatial expression profile in the gymnosperm species Norway spruce (Picea abies) as in pea. Induced cap development provides a means to profile cell-specific gene expression among phylogenetically diverse species from the early moments of mitosis and cellular differentiation.     

High productivity of wheat intercropped with maize is associated with plant architectural responses

Mixed cultivation of crops often results in increased production per unit land area, but the underlying mechanisms are poorly understood. Plants in intercrops grow differently from plants in single crops; however, no study has shown the association between plant plastic responses and the yield advantage. Here, we assessed the productivity of wheat–maize intercropping as compared to sole wheat and sole maize, and the associated differences in wheat shoot and leaf traits. In two field experiments, intercrop wheat and maize were both grown in alternating strips consisting of six rows of wheat and two rows of maize. The traits of wheat plants in border rows of the strips were compared to the traits of plants in the inner rows as well as those in sole wheat. Leaf development, chlorophyll concentration and azimuth, as well as the final leaf and ear sizes, tiller dynamics of wheat and yield components of both crops were determined. The relative densities of wheat and maize in the intercrop were 0.33 and 0.67, respectively, but the corresponding relative yields compared to the respective monocultures were 0.46 for wheat and 0.77 for maize. Compared to wheat plants in the inner rows of the intercrop strips as well as in the monoculture, border‐row wheat plants in the intercrop strips had (a) more tillers owing to increased tiller production and survival, and thus more ears, (b) larger top leaves on the main stem and tillers, (c) higher chlorophyll concentration in leaves, (d) greater number of kernels per ear and (e) smaller thousand‐grain weight. Grain yield per metre row length of border‐row wheat was 141% higher than the sole wheat, and was 176% higher than the inner‐row wheat. The results demonstrate the importance of plasticity in architectural traits for yield advantage in multispecies cropping systems.     

A simple explanation for the low impact of border control as a countermeasure to the spread of an infectious disease

A simple model for the effect of border control or travel restrictions is proposed. It can be used to predict the corresponding results in quite complex disease spread models and has the advantage of providing easy qualitative understanding of the effects of this kind of intervention.     

美皮康在骨科外固定架患者护理中的应用

目的:探讨美皮康应用于外固定架针孔换药方式的临床效果。方法:将骨科50例四肢骨折行外固定架固定的患者随机分成实验组24例和对照组26例。实验组以美皮康有边型敷料换药,对照组以临床常用的络合碘纱布条进行换药,比较两组每天更换敷料频次,外固定针孔及周围皮肤红肿、渗出情况,护士更换污染床单被套频次及护士满意度。结果:实验组每天更换敷料频次少于对照组(P<0.05),外固定针孔及周围皮肤红肿、渗出等情况,实验组均优于对照组(P<0.05),实验组中护士更换污染床单被套频次明显少于对照组(P<0.05),护士满意度高于对照组(P<0.05)。结论:美皮康对保护骨科外固定针孔的治疗效果优于传统络合碘纱布条换药,对预防外固定针道感染有效,同时减轻护士维持床单位整洁、减少床单被套的更换频次,提高护士的满意度。     

广西中越边境喀斯特地区叶附生苔类植物物种多样性研究

为了解日益恶化的喀斯特环境下叶附生苔类植物的分布状况,对广西中越边境喀斯特地区叶附生苔类植物多样性展开调查。结果表明,广西中越边境喀斯特地区有叶附生苔类植物5科15属43种,其中,九洲疣鳞苔(Cololejeunea yakusimensis)、巴氏薄鳞苔(Leptolejeunea balansae)、斯氏唇鳞苔(Cheilolejeunea streimannii)、麦氏细鳞苔(Lejeunea micholitzii)、巨齿细鳞苔(L.kodamae)和纤细细鳞苔(L.exilis)为广西苔藓植物新记录。该地区叶附生苔类植物区系具有热带性质和东亚分布特点。与邻近地区比较,该地区叶附生苔类植物与贵州茂兰的亲缘关系和区系关系最紧密。该地区叶附生苔类植物分布随海拔增加呈增加趋势。那坡老虎跳保护区、龙州和宁明弄岗保护区以及靖西龙邦镇风水林是叶附生苔类植物分布最丰富的地区,因此,建议应对这些地区的叶附生苔类植物进行优先保护。     

Corticolous bryophytes in microphyll fern forests of south-east Queensland: distribution on Antarctic beech (Nothofagus moorei)

Fine-scale variation in corticolous bryophyte communities was examined on the lower trunk of Antarctic beech (Nothofagus moorei) trees within microphyll fern forests of south-east Queensland. Analysis of the variation revealed that the composition and structure of the community altered with both the height above ground level and the direction of exposure. Patterns of distribution were thought to primarily reflect changes in the moisture availability on and around the basal trunk of Nothofagus moorei trees and the degree of desiccation tolerance exhibited by the various taxa.     

吡喃阿霉素联合化疗癌症的有效性与安全性

目的：探讨以吡喃阿霉素（THP）为主的联合化疗方案治疗恶性肿瘤的疗效与安全性。方法：以THP与其他2～3种抗癌药物联合治疗84例各类恶性肿。统计近期疗效,观察THP所致的心脏毒性发生率和其他并发症。结果：完全缓解14例,部分缓解30例、稳定36例,无效5例,总有效率52.38%。67例出现各类不良反应126例次,但程度均较轻。结论：以THP为主的联合化疗方案治疗恶性肿瘤疗效明显,毒性反应程度较轻。     

Multicellular scale front-to-rear polarity in collective migration

Collective cell migration does not only reflect the migration of cells at a similar speed and in the same direction, it also implies the emergence of new properties observed at the level of the cell group. This collective behavior relies on interactions between the cells and the establishment of a hierarchy amongst cells with leaders driving the group of followers. Here, we make the parallel between the front-to-rear polarity axis in single cell and the front-to-rear multicellular-scale polarity of a migrating collective which established through exchange of biochemical and mechanical information from the front to the rear and vice versa. Such multicellular-scale polarity gives the migrating group the possibility to better sense and adapt to energy, biochemical and mechanical constraints and facilitates migration over long distances in complex and changing environments.     

Rap1 Negatively Regulates the Hippo Pathway to Polarize Directional Protrusions in Collective Cell Migration

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