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2.
Maritime Spatial Planning (MSP) needs to incorporate spatial information on human impacts. As human activities and uses increase in marine and coastal waters around the world, pressures in ecosystems are also increasing, leading to multiple adverse effects on different species and habitats. The European Directive on MSP aims to achieve an integrated approach to marine governance, whilst securing and maintaining the healthy status of marine and coastal waters, in accordance with the Marine Strategy Framework Directive. The latter requires Member States to develop assessments not only on pressures and impacts, but also on the state of the marine environment and then take measures towards reaching a Good Environmental Status by 2020.The Portuguese Maritime Spatial Plan – Plano de Ordenamento do Espaço Marítimo (POEM) was developed between 2009 and 2012. In 2014 a law establishing the Basis for the Spatial Planning and Management of the National Maritime Space was enacted and in 2015 the framework for the elaboration of a new national Maritime Spatial Plan, named Situation Plan, was established. Portugal will face, in the next five years, the challenge of planning and managing its marine space, whilst promoting its sustainable use and protection.This study adapted a cumulative effects assessment model to understand how the impacts from multiple threats affect the marine and coastal ecosystems and, how this information can be used to improve the management process. Information was gathered on intensity and distribution of activities and uses for the Portuguese continental subdivision marine area, quantified and mapped their cumulative impacts in marine ecosystems, and overlapped with the POEM. Results show that impacts are spreading from the coast up to the Contiguous Zone. Higher scores appear in Transitional and Coastal Waters in the north (Viana do Castelo/Figueira da Foz), centre (Peniche/Setúbal) and south (Lagos/Faro). In some areas with higher ranks, statutes of nature conservation are already in place, but potential activities may still occur on top of existing ones. This study shows that the adapted model is a helpful tool to clarify ocean planning, identify areas of potential conflicts among users and support the decision making process. 相似文献
3.
T. Phanitchat C. Apiwathnasorn S. Sungvornyothin Y. Samung S. Dujardin J.‐P. Dujardin S. Sumruayphol 《Medical and veterinary entomology》2019,33(4):476-484
Wing geometry helps to identify mosquito species, even cryptic ones. On the other hand, temperature has a well‐known effect on insect metric properties. Can such effects blur the taxonomic signal embedded in the wing? Two strains of Aedes albopictus (laboratory and field strain) were examined under three different rearing temperatures (26, 30 and 33 °C) using landmark‐ and outline‐based morphometric approaches. The wings of each experimental line were compared with Aedes aegypti. Both approaches indicated similar associations between wing size and temperature. For the laboratory strain, the wing size significantly decreased as the temperature increased. For the field strain, the largest wings were observed at the intermediate temperature. The two morphometric approaches describing shape showed different sensibilities to temperature. For both strains and sexes, the landmark‐based approach disclosed significant wing shape changes with temperature changes. The outline‐based approach showed lesser effects, detecting significant changes only in laboratory females and in field males. Despite the size and shape changes induced by temperature, the two strains of Ae. albopictus were always distinguished from Ae. aegypti. The present study confirms the lability of size. However, it also suggests that, despite environmentally‐induced variation, the architecture of the wing still provides a strong taxonomic signal. 相似文献
4.
Takashi Nagai 《人类与生态风险评估》2014,20(3):641-657
An algal population growth model integrated with toxicokinetics was developed for assessing the effect of pesticides on population dynamics. This model is a simple one-compartment, first-order kinetic model in which toxicity (growth inhibition and mortality) depends on the intracellular effective concentration of a pesticide at a target site. The model's parameters were derived using an experimental study that investigated the effects of pretilachlor, bensulfuron-methyl, pentoxazone, and quinoclamine on the growth, mortality, and subsequent population recovery of the green alga Pseudokirchneriella subcapitata. Modeled and measured trajectories of algal population dynamics agreed well. The effect on population recovery was underestimated by the model that ignored the toxicokinetics. The four tested herbicides had a variety of toxicity characteristics and physicochemical properties, indicating the wide range of the model's applicability. Moreover, the developed model and the obtained model's parameters were extrapolated to predict long-term algal population dynamics under time-varying herbicide exposure. The calculated integral biomass lost compared with the control was considered a quantitative index of the population-level ecological risk. The model's prediction showed that the same exposure level (peak concentration is equivalent to EC50) indicated much different population-level effect depending on the herbicide. 相似文献
5.
Forest density expressing the stocking status constitutes the major stand physiognomic parameter of Indian forest. Density
and age are often taken as surrogate to structural and compositional changes that occur with the forest succession. Satellite
remote sensing spectral response is reported to provide information on structure and composition of forest stands. The various
vegetation indices are also correlated with forest canopy closure. The paper presents a three way crown density model utilizing
the vegetation indices viz., advanced vegetation index, bare soil index and canopy shadow index for classification of forest
crown density. The crop and water classes which could not be delineated by the model were finally masked from normalized difference
vegetation index and TM band 7 respectively. The rule based approach has been implemented for land use and forest density
classification. The broad land cover classification accuracy has been found to be 91.5%. In the higher forest density classes
the classification accuracy ranged between 93 and 95%, whereas in the lower density classes it was found to be between 82
and 85%. 相似文献
6.
Karin Schubert Dieter Reiml Jean-Pierre Accolas Franz Fiedler 《Archives of microbiology》1993,160(3):222-228
The primary structure of the peptidoglycan and the teichoic acids of two coryneform isolates from the surface flora of French cooked cheeses, CNRZ 925 and CNRZ 926, have been determined. In the peptidoglycan, meso-diaminopimelic acid was localized in position three of the peptide subunit. It contained an d-glutamyl-d-aspartyl interpeptide bridge, connecting meso-diaminopimelic acid and d-alanine residues of adjacent peptide subunits. The -carboxyl group of d-glutamic acid in position two of peptide subunits was substituted with glycine amide. The teichoic acid pattern and composition differed between the strains: both contained an erythritol teichoic acid and strain CNRZ 925 also contained an N-acetylglucosaminylphosphate polymer. The erythritol teichoic acids differed in terms of the quality and quantity of substituents, but they both had N,N-diacetyl-2,3-diamino-2,3-dideoxyglucuronic acid in common.Abbreviations DNP
dinitrophenyl
- Ery
erythritol
- Gal
galactose
- GlcN
glucosamine
- GlcNAc
N-acetylglucosamine
- GlcUANAc2
N,N-diacetyl-2,3-diamino-2,3-dideoxyglucuronic acid
- Hex UANAc2
N,N-diacetyl-2,3-diamino-2,3-dideoxyhexuronic
- acid
m-Dpm, meso-diaminopimelic acid
- Mur
muramic acid
- MurNAc
N-acetylmuramic acid 相似文献
7.
Hannes Flckner Michael Braxenthaler Peter Lackner Markus Jaritz Maria Ortner Manfred J. Sippl 《Proteins》1995,23(3):376-386
The prediction experiment reveals that fold recognition has become a powerful tool in structural biology. We applied our fold recognition technique to 13 target sequences. In two cases, replication terminating protein and prosequence of subtilisin, the predicted structures are very similar to the experimentally determined folds. For the first time, in a public blind test, the unknown structures of proteins have been predicted ahead of experiment to an accuracy approaching molecular detail. In two other cases the approximate folds have been predicted correctly. According to the assessors there were 12 recognizable folds among the target proteins. In our postprediction analysis we find that in 7 cases our fold recognition technique is successful. In several of the remaining cases the predicted folds have interesting features in common with the experimental results. We present our procedure, discuss the results, and comment on several fundamental and technical problems encountered in fold recognition. © 1995 Wiley-Liss, Inc. 相似文献
8.
继前面的工作把测试蛋白从三族扩大到十一族,寻求联配参数的普适“缺省值“;比较不同的主链曲率和挠率的计算方法,进一步确认主链的折红红分几何刻划方法的有效性;寻找有效的可变缺失突变惩罚函数的形式。结果表明,编制的蛋白质多重联配软件系统是满意的,可用于蛋白质三维结构预测。 相似文献
9.
Chen Xu Bing Wang Hailu Heng Jiangmei Huang Cuihong Wan 《Molecular & cellular proteomics : MCP》2022,21(4):100224
The filamentous cyanobacterium Anabaena sp. PCC 7120 can differentiate into heterocysts to fix atmospheric nitrogen. During cell differentiation, cellular morphology and gene expression undergo a series of significant changes. To uncover the mechanisms responsible for these alterations, we built protein–protein interaction (PPI) networks for these two cell types by cofractionation coupled with mass spectrometry. We predicted 280 and 215 protein complexes, with 6322 and 2791 high-confidence PPIs in vegetative cells and heterocysts, respectively. Most of the proteins in both types of cells presented similar elution profiles, whereas the elution peaks of 438 proteins showed significant changes. We observed that some well-known complexes recruited new members in heterocysts, such as ribosomes, diflavin flavoprotein, and cytochrome c oxidase. Photosynthetic complexes, including photosystem I, photosystem II, and phycobilisome, remained in both vegetative cells and heterocysts for electron transfer and energy generation. Besides that, PPI data also reveal new functions of proteins. For example, the hypothetical protein Alr4359 was found to interact with FraH and Alr4119 in heterocysts and was located on heterocyst poles, thereby influencing the diazotrophic growth of filaments. The overexpression of Alr4359 suspended heterocyst formation and altered the pigment composition and filament length. This work demonstrates the differences in protein assemblies and provides insight into physiological regulation during cell differentiation. 相似文献
10.
Alignments grow, secondary structure prediction improves. 总被引:12,自引:0,他引:12
Using information from sequence alignments significantly improves protein secondary structure prediction. Typically, more divergent profiles yield better predictions. Recently, various groups have shown that accuracy can be improved significantly by using PSI-BLAST profiles to develop new prediction methods. Here, we focused on the influences of various alignment strategies on two 8-year-old PHD methods. The following results stood out. (i) PHD using pairwise alignments predicts about 72% of all residues correctly in one of the three states: helix, strand, and other. Using larger databases and PSI-BLAST raised accuracy to 75%. (ii) More than 60% of the improvement originated from the growth of current sequence databases; about 20% resulted from detailed changes in the alignment procedure (substitution matrix, thresholds, and gap penalties). Another 20% of the improvement resulted from carefully using iterated PSI-BLAST searches. (iii) It is of interest that we failed to improve prediction accuracy further when attempting to refine the alignment by dynamic programming (MaxHom and ClustalW). (iv) Improvement through family growth appears to saturate at some point. However, most families have not reached this saturation. Hence, we anticipate that prediction accuracy will continue to rise with database growth. 相似文献