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Zusammenfassung Es werden zwei neue Arten der Gattung Hansenula, H. panis und H. nivea, beschrieben, die der Verfasser aus Sauerteig (Hefe) gezüchtet hat, wie er zum Brotbacken im Haushalt verwendet wird. In solchem Sauerteig werden Hansenula-Formen zahlreich gefunden.  相似文献   
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Forest vegetation is known to increase hillslope stability by reinforcing soil shear resistance and by influencing hydrologic conditions of soil. Although the importance of plant root systems for hillslope stability has received considerable attention in recent years, the quantification of such an effect needs more investigation. In this paper, we present a synthesis of the data gathered in the last 5 years for some species in different locations of the Alps and Prealps of Lombardy (Northern Italy) with the aim to increase our knowledge on root tensile strength and on Root Area Ratio distribution within the soil. Concerning root tensile strength we developed tensile strength–diameter relationships for eight species: green alder (Alnus viridis(Chaix) D.C.), beech (Fagus sylvatica L.), red willow (Salix purpurea L.), goat willow (Salix caprea L.), hazel (Corylus avellana L.), European ash (Fraxinus excelsior L.), Norway spruce (Picea abies (L.) Karst.) and European larch (Larix decidua Mill.). Results show a great variability among the different species and also for the same species. In general, however, root strength (in terms of tension) tends to decrease with diameter according to a power law, as observed by other Authors. Comparing the power law fitting curves for the considered species, it can be observed that they fall in a relatively narrow band, with the exception of hazel, which appears the most resistant. Concerning the evaluation of root distribution within the soil we estimated the Root Area Ratio (the ratio between the area occupied by roots in a unit area of soil) according to its depth for five species (beech, Norway spruce, European larch, mixed hazel and ash) in three locations of Lombardy. Results show that there is a great variability of root density for the same species well as for different points at the same locality. The general behaviour of root density, in any case, is to decrease with depth according to a gamma function for all the studied species. The results presented in this paper contribute to expanding the knowledge on root resistance behaviour and on root density distribution within the soil. The studied location have allowed the implementation of soil–root reinforcement models and the evaluation of the vegetation contribution to soil stability.  相似文献   
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Food availability may influence primates’ home range size and use. Understanding this relationship may facilitate the design of conservation strategies. We aimed to determine how fruit availability influences the ranging patterns of a group of northern pig-tailed macaques (Macaca leonina) living around the visitor center of Khao Yai National Park, Thailand. We predicted that macaques would increase their range during low fruit abundance periods to gather high-quality food and that they would go where there are more fruits or more fruits of particular species. We also predicted that human food, linked to human presence, would attract the macaques. We followed the macaques and recorded their diet and movements within their home range. We superimposed a grid on kernels defining the monthly home range surface to compare spatially macaques’ travel and the availability of fruits measured on botanical transects. Our results showed that the macaques increased their monthly home range in March, probably to obtain newly available fruits. During high fruit abundance seasons, they spent more time near particular fruit species. In August and September, although fruits became rare again, macaques kept their home range large, perhaps to find enough fruits as supplies dwindled. Finally, from October to February, they decreased their monthly home range size while consuming human food, a high-quality item. In conclusion, the macaques used several ranging strategies according to fruit availability. However, we think that, without human food, macaques would tend to increase their range during low fruit abundance periods, as predicted.  相似文献   
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Biofouling is one of the challenges that can strongly affect the finfish farm economy. Although several studies on biofouling in aquaculture have been conducted in the Mediterranean Sea, they focused on specific taxa or were limited to a particular period of sampling. The present study investigated for the first time the development, composition and variation in a biofouling community in a finfish farm with immersion time, season and depth. The results indicate that all these factors influence biofouling succession and recruitment. Moreover, the species that had a crucial role in structuring the community and in the farm cleaning activities were the ascidian Styela plicata and the bivalve Mytilus galloprovincialis. Compared with the literature data, the results highlight the heterogeneity in the composition of the biofouling present in the Mediterranean Sea. Moreover, such knowledge of the biofouling community could provide important information about management efforts and the costs that farmers will face when siting new fish farms.  相似文献   
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Neural stem cells (NSCs) are self-renewing cells that can differentiate into multiple neural lineages and repopulate regions of the brain after injury. We have investigated the role of endocannabinoids (eCBs), endogenous cues that modulate neuronal functions including neurogenesis, and their receptors CB1 and CB2 in mouse NSCs. Real-time PCR and Western blot analyses indicated that CB1 is present at higher levels than CB2 in NSCs. The eCB anandamide (AEA) or the CB1-specific agonist ACEA enhanced NSC differentiation into neurons, but not astrocytes and oligodendrocytes, whereas the CB2-specific agonist JWH133 was ineffective. Conversely, the effect of AEA was inhibited by CB1, but not CB2, antagonist, corroborating the specificity of the response. CB1 activation also enhanced maturation of neurons, as indicated by morphometric analysis of neurites. CB1 stimulation caused long-term inhibition of the ERK1/2 pathway. Consistently, pharmacological inhibition of the ERK1/2 pathway recapitulated the effects exerted by CB1 activation on neuronal differentiation and maturation. Lastly, gene array profiling showed that CB1 activation augmented the expression of genes involved in neuronal differentiation while decreasing that of stemness genes. These results highlight the role of CB1 in the regulation of NSC fate and suggest that its activation may represent a pro-neuronal differentiation signal.  相似文献   
18.
Leuciscine fishes represent an important component of freshwater ichthyofauna endemic to northern Mediterranean areas. This lineage shows high intra-specific morphological variability and exhibits high levels of hybridization, two characteristics that contribute to systematic uncertainties, misclassification of taxa and, potentially, the mismanagement of biodiversity. This study focused on brook chub, Squalius lucumonis, an endemic taxon of Central Italy. The taxonomic status of this species has long been questioned, and a hybrid origin from sympatric leusciscines (S. squalus x Rutilus rubilio, or S. squalus x Telestes muticellus) has been hypothesised. A phenotypic (evaluating shape and meristic counts) and genetic (using mitochondrial and nuclear markers) investigation of these four taxa was conducted to test species delimitation in sympatric areas and to evaluate the taxonomic status of S. lucumonis. One hundred and forty-five individuals of all four taxa were collected within streams of the lowest portion of the Tiber River basin and analysed; this region encompasses a large portion of the S. lucumonis distribution. The different morphological and genetic approaches were individually examined, compared, and then combined in a quantitative model to both investigate the limits of each approach and to identify cases of misclassification. The results obtained confirm the cladogenetic non-hybrid origin of S. lucumonis, highlight the need for immediate conservation actions and emphasise the value of an integrated approach in the study of leuciscines evolution.  相似文献   
19.
Abstract

Systemic sclerosis (SSc) is a multisystem autoimmune disease: characterised from the clinical side by progressive vasculopathy and fibrosis of the skin and different organs and from the biochemical side by fibroblast deregulation with excessive production of collagen and increased expression of nicotinamide adenine dinucleotide phosphate oxidase 4 (NOX4). The latter contributes to an overproduction of reactive oxygen species that through an autocrine loop maintains NOX4 in a state of activation. Reactive oxygen and nitrogen species are implicated in the origin and perpetuation of several clinical manifestations of SSc having vascular damage in common; attempts to dampen oxidative and nitrative stress through different agents with antioxidant properties have not translated into a sustained clinical benefit. Objective of this narrative review is to describe the origin and clinical implications of oxidative and nitrative stress in SSc, with particular focus on the central role of NOX4 and its interactions, to re-evaluate the antioxidant approaches so far used to limit disease progression, to appraise the complexity of antioxidant treatment and to touch on novel pathways elements of which may represent specific treatment targets in the not so distant future.  相似文献   
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