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881.
The main purpose of this study was the development of an impact evaluation model to effectively assess and map possible ecological impacts due to a dam construction on habitats and species from the nearest Natura 2000 sites. A new approach has been developed in order to assess and map possible impacts on habitats due to a dam construction at both construction and operation phase. This methodology includes procedures in order to assess impacts and by calculating evaluation scores. Using Geographical Information Systems (GIS) evaluation scores were assigned to grouped habitat regions at construction and operation dam phase. The construction may affect the presence of the species Lutra at the site near the river but will have no effect at the area where the dam basin and the Natura 2000 site intersect. The other species are not expected to be affected from the dam construction. During the operation phase, the presence of water will influence species like Bombina in a very positive way. The dam operation itself will not have negative effects on the rest of habitats but due to the presence of water, factors like a possible increase on traffic and population may affect negatively the habitats especially near the village areas. The proposed methodology offers an alternative point of view on impact assessment and it is expected to serve as become a valuable tool for decision makers to evaluate potential impacts to threatened species and habitats due to a technical project at construction and operation phase.  相似文献   
882.

Background, aim and scope  

Assuming that the goal of social life cycle assessment (SLCA) is to assess damage and benefits on its ‘area of protection’ (AoP) as accurately as possible, it follows that the impact pathways, describing the cause effect relationship between indicator and the AoP, should have a consistent theoretical foundation so the inventory results can be associated with a predictable damage or benefit to the AoP. This article uses two concrete examples from the work on SLCA to analyse to what extent this is the case in current practice. One considers whether indicators included in SLCA approaches can validly assess impacts on the well-being of the stakeholder, whereas the other example addresses whether the ‘incidence of child labour’ is a valid measure for impacts on the AoPs.  相似文献   
883.
884.
Uridine 5′‐diphosphate (UDP)‐glucose is transported into the lumen of the endoplasmic reticulum (ER), and the Arabidopsis nucleotide sugar transporter AtUTr1 has been proposed to play a role in this process; however, different lines of evidence suggest that another transporter(s) may also be involved. Here we show that AtUTr3 is involved in the transport of UDP‐glucose and is located at the ER but also at the Golgi. Insertional mutants in AtUTr3 showed no obvious phenotype. Biochemical analysis in both AtUTr1 and AtUTr3 mutants indicates that uptake of UDP‐glucose into the ER is mostly driven by these two transporters. Interestingly, the expression of AtUTr3 is induced by stimuli that trigger the unfolded protein response (UPR), a phenomenon also observed for AtUTr1, suggesting that both AtUTr1 and AtUTr3 are involved in supplying UDP‐glucose into the ER lumen when misfolded proteins are accumulated. Disruption of both AtUTr1 and AtUTr3 causes lethality. Genetic analysis showed that the atutr1 atutr3 combination was not transmitted by pollen and was poorly transmitted by the ovules. Cell biology analysis indicates that knocking out both genes leads to abnormalities in both male and female germ line development. These results show that the nucleotide sugar transporters AtUTr1 and AtUTr3 are required for the incorporation of UDP‐glucose into the ER, are essential for pollen development and are needed for embryo sac progress in Arabidopsis thaliana.  相似文献   
885.
Alternative splicing (AS) of precursor mRNAs is a widespread phenomenon in plants; however, many questions, especially regarding its regulation and functional implications, remain to be elucidated. In vertebrates, polypyrimidine tract‐binding proteins (PTBs) have been identified as key splicing factors influencing splice site selection and orchestrating coordinated splicing programmes during developmental processes. Here, we analysed three PTB homologues from Arabidopsis thaliana and provide evidence for their gene regulatory potential based on AS and a splicing‐independent mechanism. Our data reveal that Arabidopsis PTB homologues are subject to extensive auto‐ and cross‐regulation via AS‐coupled nonsense‐mediated decay, thereby establishing a basis for interlinking their expression. Furthermore, the multiple modes of action of Arabidopsis PTB homologues are reflected in their subcellular localization in the nucleus, cytosol and processing bodies. This work provides insight into the regulation of AS in plants and highlights the regulatory potential of the multifunctional plant PTB homologues, which might have important implications in diverse biological processes.  相似文献   
886.
887.
The synthesis of a series of novel macrocyclic compounds designed to target blood coagulation Factor XIa is described. The compounds were evaluated for their inhibition of a small set of serine proteases. Several compounds displayed modest activity and good selectivity for Factor XIa. Within the series, a promising lead structure for developing novel macrocyclic inhibitors of thrombin was identified.  相似文献   
888.
Nicotinamides of benzyl-substituted 4-aminopiperidines and their seven-membered analogs of generic structure 2 and 2′ have been discovered as potent and selective SST5 antagonists. The activity (Ki) ranges from 2.4 to 436 nM. Most compounds exhibit decent physicochemical properties and follow a clear SAR pattern. Interestingly enough, the receptor is strongly enantiodiscriminating and binds in the amino-azepane-series only the (R)-enantiomer.  相似文献   
889.
A series of macrocyclic peptidic BACE-1 inhibitors was designed. While potency on BACE-1 was rather high, the first set of compounds showed poor brain permeation and high efflux in the MDRI–MDCK assay. The replacement of the secondary benzylamino group with a phenylcyclopropylamino group maintained potency on BACE-1, while P-glycoprotein-mediated efflux was significantly reduced and brain permeation improved. Several compounds from this series demonstrated acute reduction of Aβ in human APP-wildtype transgenic (APP51/16) mice after oral administration.  相似文献   
890.
Replacement of a secondary amide with an N-acyl or N-sulfonyl gem-disubstituted azacyle in a series of CCR5 antagonists led to the identification of compounds with excellent in vitro HIV antiviral activity and increased intrinsic membrane permeability.  相似文献   
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