363 research outputs found
Urban society and the English Revolution : the archaeology of the new Jerusalem
The English Revolution has long been a defining subject of English historiography, with a large and varied literature that reflects continuing engagement with the central themes of civil conflict, and deep-rooted social, political and religious change. By contrast, this period has failed to catch the imagination of archaeologists. This research seeks to understand the world of the English Revolution through its material expression in English towns. Identifying the material expressions of the period is central to developing an archaeological understanding of the period. The clearest material expressions are found, in the fortifications that were built to protect towns, the destruction that was wrought on towns and in the reconstruction of the material world of English towns. Towns, like any other artefact, have their meanings. These meanings are multivalent and ever shifting, defined by the interaction of their material fabric and those who experience it. As these meanings change over time, they can be traced through the structures and artefacts of the town, and through the myths and legends that accrete on them. Understanding the interactions of material, myth and memory allows archaeologists to understand the true meaning of the urban built environment to generate a deeper and more nuanced understanding of the nature of the English urban culture of the period. Towns were fundamental to the English imagination as much as they were economically, politically or socially important. The English Revolution sits at the heart of the accepted conception of historical archaeology, but has been curiously neglected by historical archaeologists. The cultural conflict of this period embodies the themes that are central to historical archaeology, and nowhere is this more apparent than in urban culture.EThOS - Electronic Theses Online ServiceGBUnited Kingdo
GM1 promotes TrkA-mediated neuroblastoma cell differentiation by occupying a plasma membrane domain different from TrkA
Recently, we highlighted that the ganglioside GM1 promotes neuroblastoma cells differentiation by activating the TrkA receptor through the formation of a TrkA\u2013GM1 oligosaccharide complex at the cell surface. To study the TrkA\u2013GM1 interaction, we synthesized two radioactive GM1 derivatives presenting a photoactivable nitrophenylazide group at the end of lipid moiety, 1 or at position 6 of external galactose, 2; and a radioactive oligosaccharide portion of GM1 carrying the nitrophenylazide group at position 1 of glucose, 3. The three compounds were singly administered to cultured neuroblastoma Neuro2a cells under established conditions that allow cell surface interactions. After UV activation of photoactivable compounds, the proteins were analyzed by PAGE separation. The formation of cross-linked TrkA\u2013GM1 derivatives complexes was identified by both radioimaging and immunoblotting. Results indicated that the administration of compounds 2 and 3, carrying the photoactivable group on the oligosaccharide, led to the formation of a radioactive TrkA complex, while the administration of compound 1 did not. This underlines that the TrkA\u2013GM1 interaction directly involves the GM1 oligosaccharide, but not the ceramide. To better understand how GM1 relates to the TrkA, we isolated plasma membrane lipid rafts. As expected, GM1 was found in the rigid detergent-resistant fractions, while TrkA was found as a detergent soluble fraction component. These results suggest that TrkA and GM1 belong to separate membrane domains: probably TrkA interacts by \u2018flopping\u2019 down its extracellular portion onto the membrane, approaching its interplay site to the oligosaccharide portion of GM1. (Figure presented.)
Are Amphipod invaders a threat to the regional biodiversity? Conservation prospects for the Loire River
The impact of invasions on local biodiversity is well established, but their impact on regional biodiversity has so far been only sketchily documented. To address this question, we studied the impact at various observation scales (ranging from the microhabitat to the whole catchment) of successive arrivals of non-native amphipods on the amphipod assemblage of the Loire River basin in France. Amphipod assemblages were studied at 225 sites covering the whole Loire catchment. Non-native species were dominant at all sites in the main channel of the Loire River, but native species were still present at most of the sites. We found that the invaders have failed to colonize most of tributaries of the Loire River. At the regional scale, we found that since the invaders first arrived 25 years ago, the global amphipod diversity has increased by 33% (from 8 to 12 species) due to the arrival of non-native species. We discuss the possibility that the lack of any loss of biodiversity may be directly linked to the presence of refuges at the microhabitat scale in the Loire channel and in the tributaries, which invasive species have been unable to colonize. The restoration of river quality could
increase the number of refuges for native species, thus
reducing the impact of invader
A Scalable Neuro-inspired Robot Controller Integrating a Machine Learning Algorithm and a Spiking Cerebellar-like Network
Catalase vs Peroxidase Activity of a Manganese(II) Compound: Identification of a Mn(III)-(μ-O)2-Mn(IV) Reaction Intermediate by Electrospray Ionization Mass Spectrometry and Electron Paramagnetic Resonance Spectroscopy
Herein, we report reactivity studies of the mononuclear water-soluble complex [Mn(II)(HPClNOL)(η1-NO3)(η2-NO3)]
1, where HPClNOL ) 1-(bis-pyridin-2-ylmethyl-amino)-3-chloropropan-2-ol, toward peroxides (H2O2 and tertbutylhydroperoxide).
Both the catalase (in aqueous solution) and peroxidase (in CH3CN) activities of 1 were evaluated
using a range of techniques including electronic absorption spectroscopy, volumetry (kinetic studies), pH monitoring
during H2O2 disproportionation, electron paramagnetic resonance (EPR), electrospray ionization mass spectrometry
in the positive ion mode [ESI(+)-MS], and gas chromatography (GC). Electrochemical studies showed that 1 can
be oxidized to Mn(III) and Mn(IV). The catalase-like activity of 1 was evaluated with and without pH control. The
results show that the pH decreases when the reaction is performed in unbuffered media. Furthermore, the activity
of 1 is greater in buffered than in unbuffered media, demonstrating that pH influences the activity of 1 toward H2O2.
For the reaction of 1 with H2O2, EPR and ESI(+)-MS have led to the identification of the intermediate [Mn(III)Mn(IV)(μ-
O)2(PClNOL)2]+. The peroxidase activity of 1 was also evaluated by monitoring cyclohexane oxidation, using H2O2
or tert-butylhydroperoxide as the terminal oxidants. Low yields (<7%) were obtained for H2O2, probably because it
competes with 1 for the catalase-like activity. In contrast, using tert-butylhydroperoxide, up to 29% of cyclohexane
conversion was obtained. A mechanistic model for the catalase activity of 1 that incorporates the observed lag
phase in O2 production, the pH variation, and the formation of a Mn(III)-(μ-O)2-Mn(IV) intermediate is proposed
Association of intronic variants of the KCNAB1 gene with lateral temporal epilepsy.
The KCNAB1 gene is a candidate susceptibility factor for lateral temporal epilepsy (LTE) because of its functional interaction with LGI1, the gene responsible for the autosomal dominant form of LTE. We investigated association between polymorphic variants across the KCNAB1 gene and LTE. The allele and genotype frequencies of 14 KCNAB1 intronic SNPs were determined in 142 Italian LTE patients and 104 healthy controls and statistically evaluated. Single SNP analysis revealed one SNP (rs992353) located near the 3'end of KCNAB1 slightly associated with LTE after multiple testing correction (odds ratio=2.25; 95% confidence interval 1.26-4.04; P=0.0058). Haplotype analysis revealed two haplotypes with frequencies higher in cases than in controls, and these differences were statistically significant after permutation tests (Psim=0.047 and 0.034). One of these haplotypes was shown to confer a high risk for the syndrome (odds ratio=12.24; 95% confidence interval 1.32-113.05) by logistic regression analysis. These results support KCNAB1 as a susceptibility gene for LTE, in agreement with previous studies showing that this gene may alter susceptibility to focal epilepsy
Distributed cerebellar plasticity implements generalized multiple-scale memory components in real-robot sensorimotor tasks
The cerebellum plays a crucial role in motor learning and it acts as a predictive controller. Modeling it and embedding it into sensorimotor tasks allows us to create functional links between plasticity mechanisms, neural circuits and behavioral learning. Moreover, if applied to real-time control of a neurorobot, the cerebellar model has to deal with a real noisy and changing environment, thus showing its robustness and effectiveness in learning. A biologically inspired cerebellar model with distributed plasticity, both at cortical and nuclear sites, has been used. Two cerebellum-mediated paradigms have been designed: an associative Pavlovian task and a vestibulo-ocular reflex, with multiple sessions of acquisition and extinction and with different stimuli and perturbation patterns. The cerebellar controller succeeded to generate conditioned responses and finely tuned eye movement compensation, thus reproducing human-like behaviors. Through a productive plasticity transfer from cortical to nuclear sites, the distributed cerebellar controller showed in both tasks the capability to optimize learning on multiple time-scales, to store motor memory and to effectively adapt to dynamic ranges of stimuli.This work was supported by grants of European Union: REALNET (FP7-ICT270434) and Human Brain Project (HBP-604102)
Triangles and tetrahedra: metal directed self-assembly of metallo-supramolecular structures incorporating bis-b-diketonato ligands
Intérêt écologique des galeries de drainage
Artificial subterranean habitats can be of important ecological interest. Draining galleries
are a typology of artificial springs with underground development characterized by an almost horizontal
tunnel that penetrates the side of a slope, to catch the subterranean water and bring it outward. They are a
very ancient spring catching technique and provide interesting unstudied subterranean habitats. In this study
we surveyed 18 draining galleries in NW Italy. We provide specific environmental data that can help to
support broad conclusions on the ecological features and value of these habitats. We found that they house
permanent waterbodies, have lengths up to 120 m, are characterized by climatic conditions similar to those
of natural caves. We collected several taxa of organisms, adapted to subterranean life as well as coming from
outside environment, which find inside draining galleries shelter, roosting and breeding sites. We tested the
role of accessibility in determining galleries biodiversity and we found that the latter is scarcely affected.
From a conservationist point of view draining galleries can have important ecological value, particularly in
areas devoid of natural subterranean habitatsLes environnements souterrains artificiels peuvent être très intéressants d'une point de vue écologique. Les galeries drainantes sont des sources artificielles avec un développement hypogé constitué par une galerie presque
horizontale qui s'étend à l'intérieur d'un relief. Il s'agit d'une technique de captage très ancienne qui a créé des habitats souterrains non ou peu étudiés et qui sont potentiellement très intéressants d'un point de vue écologique. Nous avons étudié 18 galeries drainantes dans le nord-ouest
de l'Italie. Nous présentons des données écologiques spécifiques qui peuvent aider à formuler des conclusions générales sur les caractéristiques écologiques de ces habitats hypogés. Les galeries drainantes, qui dans la région d'étude atteignent 120 m de longueur, offrent la présence de
biotopes humides permanents et ont des caractéristiques climatiques semblables à celles des grottes. Elles constituent des refuges et des sites de reproduction tant à des organismes typiques de la faune cavernicole qu'à beaucoup de taxons provenant de l'extérieur. Nous n'avons pas observé
d'influence statistiquement significative de l'accessibilité des sites sur leur niveau de biodiversité. Du point de vue de la conservation les galeries de drainage présentent une valeur écologique certaine, surtout dans les zones dépourvues d'environnements souterrains naturels
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