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81.
82.
In the years 2003 and 2004 we have observed an about 70 hectare large area in the Düsseltal, the eastern part of the Neandertal in North Rhine-Westphalia. There we collected on trees, bushes and herbs and found about 150 microfungi of which some are new for Germany or the entire world. E.g.: Pseudocercospora populigena N. ALE-AGHA, U. BRAUN & G.B. FEIGE on Populus berolinensis; Vialaea insculpta (FR.) SACC. on Ilex aquifolium L.; Passalora amelopsidis (PECK.) U. BRAUN on Parthenocissus quinquefolia (L.) PLANCH.: Pleiochaeta setosa (KIRCHN.) HUGHES on Genista angelica L.; Cercospora mercurialis PASS. on Mercurialis perennis L. (new for NRW); Pleurocytospora vestita PETRAK on Ribes aureum PURSH.; Gonatobotrys simplex CORDA on Lolium perenne L.; Phomatospora berckleyi SACC. on Dactylis glomerata L. and so on. All specimens are located in the Herbarium ESS, Mycotheca Parva collection G.B. Feige & N. Ale-Agha.  相似文献   
83.
During our investigation on microfungi in North Rhine Westphalia in the years 2002 and 2003 we were able to collect and identify some new and rare species of microfungi as parasites and saprophytes on wild and ornamental plants. Some of these like Erysiphe elevata (BURILL.) U. BRAUN & S. TAKAMATSU COMB. NOV. [=Microsphaera elevata BURILL.] on Catalpa bignonioides WALT., Erysiphe syringae-japonicae (U. BRAUN) U. BRAUN & S. TAKAMATSU [= Microsphaera syringae-japonicae U. BRAUN, M. aceris BUNKINA. KOMAROVSKIE CHTENIYA, Erysiphe acerina U. BRAUN & S. TAKAMATSU] on Acer campestre L. and Acer barinerve L., Mycosphaerella iridis (DESM.) SCHROET., Ectostroma iridis FR. and Volutella melaloma BERK. & BR on Iris pseudacorus L., Puccinia doronicella P. SYD. & SYD. on Doronicum columnae TEN., Ascochyta lamiorum SACC. S.L. I=A. phlomidis BUB. & WROB.) on Phlomis tuberosa L., Colletotrichum gloeosporides (PENZ.) SACC. on Passiflora coerulea L., Oidium hortensiae JOERST on Hydrangea macrophylla (THUNB.) SER., Puccinia horiana P. HENN. on Chrysanthemum vulgare (L.) BERNH., Lophodermium pinastri (SCHRAD.) CHEV., Leptostroma pinorum SACC., Sclerophoma pythiophila (CDA) HOHN., Lichenoconium boreale (KARST.) PETRAK. & SYD., Anthostomella formosa KIRSCHST. and Sphaeropsis sapinae (FR.) DYKO & SUTTON on Pinus nigra L. are new for Germany. All samples are located in the Herbarium ESS Mycotheca Parva, Collection G.B. Feige/N. Ale-Agha.  相似文献   
84.
Plasmonics - A facile and sensitive spectroscopic detection method for the detection of cobalt ion was introduced by the use of the surface plasmon resonance of silver nanotriangles (AgTrngs)....  相似文献   
85.
Chronic inhalation of quartz particles has been implicated in lung diseases including silicosis and cancer. The aim of this study was to investigate whether quartz particles affect gap junctional intercellular communication (GJIC) in rat lung epithelial cells (RLE-6TN). Here, we demonstrate that exposure of RLE-6TN cells to subtoxic doses of DQ12 standard quartz resulted in an up to 55% reduction of GJIC, as determined in a dye transfer assay. We show that connexin-43 (Cx43) is the major connexin responsible for intercellular communication in these lung epithelial cells and that exposure to quartz particles induces a significant internalization of Cx43. Downregulation of GJIC was attenuated by N-acetyl cysteine, suggesting the involvement of reactive oxygen species and/or cellular thiol homeostasis in the regulation of GJIC. Furthermore, an inhibitor of activation of extracellular signal-regulated kinases prevented the loss of GJIC in cells exposed to DQ12 quartz, although no direct phosphorylation of Cx43 upon exposure to DQ12 was detected.  相似文献   
86.
Simulating complex biological and physiological systems and predicting their behaviours under different conditions remains challenging. Breaking systems into smaller and more manageable modules can address this challenge, assisting both model development and simulation. Nevertheless, existing computational models in biology and physiology are often not modular and therefore difficult to assemble into larger models. Even when this is possible, the resulting model may not be useful due to inconsistencies either with the laws of physics or the physiological behaviour of the system. Here, we propose a general methodology for composing models, combining the energy-based bond graph approach with semantics-based annotations. This approach improves model composition and ensures that a composite model is physically plausible. As an example, we demonstrate this approach to automated model composition using a model of human arterial circulation. The major benefit is that modellers can spend more time on understanding the behaviour of complex biological and physiological systems and less time wrangling with model composition.  相似文献   
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88.
Arid and semi‐arid areas constitute a prominent feature of the earth today, especially in Asia and Africa. Their formation started in the middle Miocene with increased stepwise aridification since the Pliocene. This aridification had strong ecological and evolutionary consequences and not only led to fragmentation of moist‐adapted biota, but also fostered the evolution of arid‐adapted taxa from mesic ancestors and triggered speciation within arid areas. The open‐habitat chats, a clade within Saxicolinae (Aves, Muscicapidae), constitute one of the most significant arid‐adapted passerine groups of Africa and Eurasia. Here, we present a temporal and spatial framework for the diversification of open‐habitat chats, using probabilistic approaches for the reconstruction of their biogeographic history based on a time‐calibrated multilocus molecular phylogenetic hypothesis. The diversification of open‐habitat chats was initiated in the late Miocene at around 7.4 Ma, most likely in sub‐Saharan Africa. Southern Africa and the Horn of Africa acted as centres of diversification and biogeographic expansion. From the latter area, the Arabo‐Sindic region and subsequently further parts of Eurasia and North Africa were colonized. The colonization history out of sub‐Saharan Africa contrasts with that of several other songbird clades, where a biogeographic expansion from Eurasia or northern Africa to southern Africa was prevalent. Habitat fragmentation through forest expansions during intermittent wetter periods in Africa influenced diversification in several clades. However, phases of increased aridity, with hyperarid regions acting as drivers of vicariance, seem to have also been important in radiations of the Arabo‐Sindic region and the Horn of Africa during the Pleistocene. Different processes such as colonization of new areas followed by vicariance or speciation across ecotones might have played a role throughout the radiation of open‐habitat chats.  相似文献   
89.
90.
In this study, the possibility of keratin extraction from wool and feather by an enzymatic treatment along with a reducing agent has been investigated. The effects of different parameters, that is, enzyme loading, type of substrate and surfactant, hydrolysis time, and reducing agent concentration, have been examined in order to optimize the enzymatic hydrolysis. The optimal condition for maximum keratin extraction was attained by making use of 1 g/L sodium dodecyl sulfate (an anionic surfactant) and 2.6% (v/v) protease (Savinase), along with 8.6 and 6.4 g/L sodium hydrogen sulfite (a reducing agent) for wool and feathers, respectively, at liquor to fiber ratio of 25 mL/g for 4 hr. The obtained results indicated higher degradation of wool fiber in comparison with feathers, which might be due to the higher hydrophilic nature of the former. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) patterns revealed that the molecular weights of the extracted proteins from wool and feather were lower than those for the untreated fibers. Scanning electron micrographs showed fibers fibrillation and degradation upon enzymatic treatment. Besides, Fourier-transform infrared (FTIR) spectra indicated no evident changes in the chemical structure of the hydrolyzed fibers. However, wool and feather remainders were mostly composed of α-helix and β-sheets conformations, respectively.  相似文献   
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