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81.
The aerosphere is utilized by billions of birds, moving for different reasons and from short to great distances spanning tens of thousands of kilometres. The aerosphere, however, is also utilized by aviation which leads to increasing conflicts in and around airfields as well as en‐route. Collisions between birds and aircraft cost billions of euros annually and, in some cases, result in the loss of human lives. Simultaneously, aviation has diverse negative impacts on wildlife. During avian migration, due to the sheer numbers of birds in the air, the risk of bird strikes becomes particularly acute for low‐flying aircraft, especially during military training flights. Over the last few decades, air forces across Europe and the Middle East have been developing solutions that integrate ecological research and aviation policy to reduce mutual negative interactions between birds and aircraft. In this paper we 1) provide a brief overview of the systems currently used in military aviation to monitor bird migration movements in the aerosphere, 2) provide a brief overview of the impact of bird strikes on military low‐level operations, and 3) estimate the effectiveness of migration monitoring systems in bird strike avoidance. We compare systems from the Netherlands, Belgium, Germany, Poland and Israel, which are all areas that Palearctic migrants cross twice a year in huge numbers. We show that the en‐route bird strikes have decreased considerably in countries where avoidance systems have been implemented, and that consequently bird strikes are on average 45% less frequent in countries with implemented avoidance systems in place. We conclude by showing the roles of operational weather radar networks, forecast models and international and interdisciplinary collaboration to create safer skies for aviation and birds.  相似文献   
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In this report we show that human DNA Topoisomerase I (Top1) forms DNA-protein adducts with nicked and gapped DNA structures lacking a conventional Top1 cleavage site. The radioactively labeled crosslinking products were identified by SDS-gel electrophoresis. The chemical structure of the groups at 5' or 3' end of the nick does not have an effect on the formation of these covalent adducts. Therefore, all kinds of nicks, either directly induced by ionizing radiation or reactive oxygen species or indirectly induced in the course of base excision repair (BER) are targets for Top1 that competes with BER proteins and other nick-sensors. Top1-DNA covalent adducts formed in cells exposed to DNA damaging agents can promote genetic instability.  相似文献   
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Family Ascocystitidae, defined and established by Georges Ubaghs in 1967, includes a single genus, Ascocystites. This genus was described and figured for the first time by Barrande in 1887, from Bohemian specimens. Thereafter, specimens brought close to Ascocystites or assigned to this genus were described starting from samples collected in Bohemia in the Armorican Massif or in Portugal. The new specimens were collected in Morocco in the Eastern Anti-Atlas, within the formation of Izzeguirene of Caradoc age. The studied material includes several sandy slabes often containing many well-preserved and almost complete individuals. These levels gather individuals of various sizes, corresponding to various stages of development. The morphological study in progress should allow a specific attribution by comparison with the Bohemian and Armorican forms actually known. The Moroccan material has, in addition, the advantage of corresponding to associations of several Echinodermata groups, rich in individuals, allowing a taphonomic and possibly paleoenvironmental study. Biostratigraphically, Ascocystitidae are actually known between Middle (Armorican Massif and Portugal) and Upper Ordovician (Bohemia and now Morocco). The discovery of Ascocystitidae in the Moroccan Anti-Atlas extends their distribution, within gondwanian domain, during Middle and Upper Ordovician.  相似文献   
86.
Nutritional metabonomics: applications and perspectives   总被引:1,自引:0,他引:1  
Nowadays, nutrition focuses on improving health of individuals through diet. Current nutritional research aims at health promotion, disease prevention, and performance improvement. Modern analytical platforms allow the simultaneous measurement of multiple metabolites providing new insights in the understanding of the functionalities of cells and whole organisms. Metabonomics, "the quantitative measurement of the dynamic multiparametric metabolic response of living systems to pathophysiological stimuli or genetic modifications", provides a systems approach to understanding global metabolic regulations of organisms. This concept has arisen from various applications of NMR and MS spectroscopies to study the multicomponent metabolic composition of biological fluids, cells, and tissues. The generated metabolic profiles are processed by multivariate statistics to maximize the recovery of information to be correlated with well-determined stimuli such as dietary intervention or with any phenotypic data or diet habits. Metabonomics is thus uniquely suited to assess metabolic responses to deficiencies or excesses of nutrients and bioactive components. Furthermore, metabonomics is used to characterize the metabolic phenotype of individuals integrating genetic polymorphism, metabolic interactions with commensal and symbiotic partners such as gut microflora, as well as environmental and behavioral factors including dietary preferences. This paper reports several experimental key aspects in nutritional metabonomics, reviews its applications employing targeted and holistic approach analysis for the study of the metabolic responses following dietary interventions. It also reports the assessment of intra- and inter-individual variability in animal and human populations. The potentialities of nutritional metabonomics for the discovery of new biomarkers and the characterization of metabolic phenotypes are discussed in a context of their possible utilizations for personalized nutrition to provide health maintenance at the individual level.  相似文献   
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The functionalization of long chain alkylamine controlled-pore glass (CPG) with a 3-hydroxypropyl-(2-cyanoethyl)thiophosphoryl linker and its conversion to the support 7 has led to the synthesis of DNA oligonucleotides and their 3'- or (3',5')-conjugates. Indeed, CPG support 7 has been successfully employed in the synthesis of both native and fully phosphorothioated DNA 20-mers. Unlike conventional succinylated CPG supports, this distinctively functionalized support allows oligonucleotide deprotection and removal of the deprotection side products to proceed without releasing the oligonucleotide into the aqueous milieu. When freed from deprotection side products, the DNA oligonucleotide is thermolytically released from the support within 2 h under nearly neutral conditions (pH 7.2, 90 degrees C). The quality of these oligonucleotides is comparable to that of identical oligonucleotides synthesized from succinylated CPG supports in terms of shorter than full length oligonucleotide contaminants and overall yields. The versatility of the thermolytic CPG support 7 is further demonstrated by the synthesis of a DNA oligonucleotide (20-mer) and its conjugation with an azido and alkynyl groups at both 5'-and 3'-termini, respectively. The functionality of the (3',5')-heteroconjugated oligonucleotide 18 is verified by its circularization to the DNA oligonucleotide 19 under "click" chemistry conditions.  相似文献   
89.
Summary We have investigated the dynamics and structural behaviour of two antigenic peptides using 1H NMR. The two cyclic peptides mimic the antigenic site A of influenza haemagglutinin protein; they only differ in the way they were cyclized and in the size of their respective linkers. Homonuclear relaxation parameters extracted from a complete NOE matrix were interpreted in terms of local dynamics. A set of distance constraints was deduced from these parameters which allowed 3D models to be constructed using distance geometry. NOE back-calculation was used to check the validity of the final models. Strong variations of internal motion amplitude have been found in both peptides along their backbone. Motions with high amplitudes have been localized in the Gly-Pro-Gly sequence which forms a -turn in both structures.Abbreviations DSS 3-(trimethylsilyl)-1-propanesulfonic acid - D-loop aspartic acid loop - ELISA enzyme-linked immunoabsorbent assay - f.i.d free induction decay - HOHAHA homonuclear Hartmann-Hahn spectroscopy - HPLC high pressure liquid chromatography - K-loop lysine loop - NMR nuclear magnetic resonance - NOE nuclear Overhauser enhancement - NOESY nuclear Overhauser enhancement spectroscopy - r.m.s.d. root-mean-square deviation of atomic positions  相似文献   
90.

Background

Associations between alcohol consumption and cognitive function are discordant and data focusing on midlife exposure are scarce.

Objective

To estimate the association between midlife alcohol consumption and cognitive performance assessed 13 y later while accounting for comorbidities and diet.

Methods

3,088 French middle-aged adults included in the SU.VI.MAX (1994) study with available neuropsychological evaluation 13 y later. Data on alcohol consumption were obtained from repeated 24h dietary records collected in 1994–1996. Cognitive performance was assessed in 2007–2009 via a battery of 6 neuropsychological tests. A composite score was built as the mean of the standardized individual test scores (mean = 50, SD = 10). ANCOVA were performed to estimate mean differences in cognitive performance and 95% confidence intervals (CI).

Results

In women, abstainers displayed lower cognitive scores than did low-to-moderate alcohol drinkers (1 to 2 drinks/day) (mean difference = −1.77; 95% CI: −3.29, −0.25). In men, heavy drinkers (>3 drinks/day) had higher cognitive scores than did low-to-moderate (1 to 3 drinks/day) (mean difference = 1.05; 95% CI: 0.10, 1.99). However, a lower composite cognitive score was detected in male drinkers consuming ≥90 g/d (≈8 drinks/d). A higher proportion of alcohol intake from beer was also associated with lower cognitive scores. These associations remained significant after adjustment for diet, comorbidities and sociodemographic factors.

Conclusion

In men, heavy but not extreme drinking was associated with higher global cognitive scores. Given the known harmful effects of alcohol even in low doses regarding risk of cancer, the study does not provide a basis for modifying current public health messages.

Trial Registration

ClinicalTrials.gov NCT00272428  相似文献   
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