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91.
Andrew Fairbairn Eleni Asouti Julie Near Danièle Martinoli 《Vegetation History and Archaeobotany》2002,11(1-2):41-54
Analysis of charred plant macro-remains, including wood charcoals, cereals, seeds, tubers and fruits from the Neolithic site
of ?atalh?yük has indicated complex patterns of plant resource use and exploitation in the Konya plain during the early Holocene.
Evidence presented in this paper shows that settlement location was not dictated by proximity to high quality arable land
and direct access to arboreal resources (firewood, timber, fruit producing species). A summary of the patterns observed in
sample composition and species representation is outlined here together with preliminary interpretations of these results
within their broader regional context.
Received September 4, 2001 / Accepted April 9, 2002 相似文献
92.
Kim E. Haworth Ira Islam Matthew Breen Wendy Putt Eleni Makrinou Matthew Binns David Hopkinson Yvonne Edwards 《Mammalian genome》2001,12(8):622-629
We describe the construction of a dog embryonic head/neck cDNA library and the isolation of the dog homolog of the Treacher
Collins Syndrome gene, TCOF1. The protein shows a similar three-domain structure to that described for human TCOF1, but the dog gene lacks exon 10 and
contains two exons not present in the human sequence. In addition, exon 19 is differentially spliced in the dog. How these
structural differences relate to TCOF1 phosphorylation is discussed. Isolation of a genomic clone allowed the exon/intron
boundaries to be characterized and the dog TCOF1 gene to be mapped to CF Chr 4q31, a region syntenic to human Chr 5. Genetic analysis of DNA of dogs from 13 different breeds
identified nine DNA sequence variants, three of which gave rise to amino acid substitutions. Grouping dogs according to head
type showed that a C396T variant, leading to a Pro117Ser substitution, is associated with skull/face shape in our dog panel.
The numbers are small, but the association between the T allele and brachycephaly, broad skull/short face, was highly significant
(p= 0.000024). The short period of time during which the domestic dog breeds have been established suggests that this mutation
has arisen only once in the history of dog domestication.
Received: 12 January 2001 / Accepted: 1 April 2001 相似文献
93.
S Takada T Magira M Yamamura 《Biochemical and biophysical research communications》1989,160(2):711-714
To investigate the effect of histone H1 on DNA primase activity, partially purified DNA primase from mouse FM3A cells was used. It was found that histone H1 dose dependently inhibited DNA primase. Interestingly phosphorylation of histone H1 reduced the inhibitory activity of the histone. However, de-phosphorylation of the phosphorylated histone H1 resumed the inhibitory activity of DNA primase. These findings lead us to the assumption that phosphorylation and de-phosphorylation of histone may regulate the cell cycle by controlling DNA synthesis through reverse inhibition of DNA primase. 相似文献
94.
Cognitive functions are stored in the connectome, the wiring diagram of the brain, which exhibits non-random features, so-called motifs. In this work, we focus on bidirectional, symmetric motifs, i.e. two neurons that project to each other via connections of equal strength, and unidirectional, non-symmetric motifs, i.e. within a pair of neurons only one neuron projects to the other. We hypothesise that such motifs have been shaped via activity dependent synaptic plasticity processes. As a consequence, learning moves the distribution of the synaptic connections away from randomness. Our aim is to provide a global, macroscopic, single parameter characterisation of the statistical occurrence of bidirectional and unidirectional motifs. To this end we define a symmetry measure that does not require any a priori thresholding of the weights or knowledge of their maximal value. We calculate its mean and variance for random uniform or Gaussian distributions, which allows us to introduce a confidence measure of how significantly symmetric or asymmetric a specific configuration is, i.e. how likely it is that the configuration is the result of chance. We demonstrate the discriminatory power of our symmetry measure by inspecting the eigenvalues of different types of connectivity matrices. We show that a Gaussian weight distribution biases the connectivity motifs to more symmetric configurations than a uniform distribution and that introducing a random synaptic pruning, mimicking developmental regulation in synaptogenesis, biases the connectivity motifs to more asymmetric configurations, regardless of the distribution. We expect that our work will benefit the computational modelling community, by providing a systematic way to characterise symmetry and asymmetry in network structures. Further, our symmetry measure will be of use to electrophysiologists that investigate symmetry of network connectivity. 相似文献
95.
Eleni Karali Beat Brunner Ruth Doherty Anna M. Hersperger Mark D. A. Rounsevell 《Human ecology: an interdisciplinary journal》2013,41(6):915-926
Identifying and interpreting the heterogeneity of farmer behaviour is becoming increasingly important in support of policy- and decision-making goals. This paper explores whether observed differences in farming practices can be interpreted from the heterogeneity of farmer behaviour. Farmer attitudes and objectives were analysed using a combination of principal components and cluster analysis applied to responses to statements in a telephone-based survey. Respondents were classified into four profiles; business-oriented, lifestylers, multifunctionalists and traditionalists. Each profile differed in terms of farm management practices, the amount of land farmers either managed or owned, the existence of successors and the importance placed on household members in providing information. The results suggest that knowledge of farmer behavioural profiles could support more targeted policy development that accounts for alternative farmer goals. However, similarities were also found between the profiles, suggesting that farmer behaviour would be better interpreted as a dynamic set of identities, rather than as static profiles. 相似文献
96.
Eleni?Petsalaki Maria?Dandoulaki George?ZachosEmail authorView authors OrcID profile 《Chromosoma》2018,127(4):461-473
Formation of stable kinetochore-microtubule attachments is essential for accurate chromosome segregation in human cells and depends on the NDC80 complex. We recently showed that Chmp4c, an endosomal sorting complex required for transport protein involved in membrane remodelling, localises to prometaphase kinetochores and promotes cold-stable kinetochore microtubules, faithful chromosome alignment and segregation. In the present study, we show that Chmp4c associates with the NDC80 components Hec1 and Nuf2 and is required for optimal NDC80 stability and Hec1-Nuf2 localisation to kinetochores in prometaphase. However, Chmp4c-depletion does not cause a gross disassembly of outer or inner kinetochore complexes. Conversely, Nuf2 is required for Chmp4c kinetochore targeting. Constitutive Chmp4c kinetochore tethering partially rescues cold-stable microtubule polymers in cells depleted of the endogenous Nuf2, showing that Chmp4c also contributes to kinetochore-microtubule stability independently of regulating Hec1 and Nuf2 localisation. Chmp4c interacts with tubulin in cell extracts, and binds and bundles microtubules in vitro through its highly basic N-terminal region (amino acids 1–77). Furthermore, the N-terminal region of Chmp4c is required for cold-stable kinetochore microtubules and efficient chromosome alignment. We propose that Chmp4c promotes stable kinetochore-microtubule attachments by regulating Hec1–Nuf2 localisation to kinetochores in prometaphase and by binding to spindle microtubules. These results identify Chmp4c as a novel protein that regulates kinetochore-microtubule interactions to promote accurate chromosome segregation in human cells. 相似文献
97.
Zoumpopoulou Georgia Tzouvanou Alexandra Mavrogonatou Eleni Alexandraki Voula Georgalaki Marina Anastasiou Rania Papadelli Marina Manolopoulou Eugenia Kazou Maria Kletsas Dimitris Papadimitriou Konstantinos Tsakalidou Effie 《Probiotics and antimicrobial proteins》2018,10(2):313-322
Probiotics and Antimicrobial Proteins - The increased consumers’ interest on the positive role of food in wellbeing and health underscores the need to determine new probiotic microorganisms.... 相似文献
98.
Aromatic amino-acid side chains are essential components for the structure and function of proteins. We present herein a set of NMR experiments for time-efficient resonance assignment of histidine and tyrosine side chains in uniformly 13C/15N-labeled proteins. The use of band-selective 13C pulses allows to deal with linear chains of coupled spins, thus avoiding signal loss that occurs in branched spin systems during coherence transfer. Furthermore, our pulse schemes make use of longitudinal 1H relaxation enhancement, Ernst-angle excitation, and simultaneous detection of 1H and 13C steady-state polarization to achieve significant signal enhancements. 相似文献
99.
Morgane Sonia Thion Donovan Low Aymeric Silvin Jinmiao Chen Pauline Grisel Jonas Schulte-Schrepping Ronnie Blecher Thomas Ulas Paola Squarzoni Guillaume Hoeffel Fanny Coulpier Eleni Siopi Friederike Sophie David Claus Scholz Foo Shihui Josephine Lum Arlaine Anne Amoyo Anis Larbi Sonia Garel 《Cell》2018,172(3):500-516.e16