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排序方式: 共有234条查询结果,搜索用时 31 毫秒
1.
Aram A. Yengoyan 《American anthropologist》2002,104(1):334-339
On Durkheim's Elementary Forms of Religious Life. N. J. Allen. W. S. F. Pickering. and W. Watts Miller. eds. New York: Routledge, 1998. 224 pp.
Marcel Mauss:. Centenary Tribute. Wendy James and N. J. Allen. eds. New York: Berghahn Press, 1998. 260 pp.
Taboo, Truth, and Religion: Franz Baermann Steiner Selected Writings, vol. 1. Jeremy Adler and Richard Fardon. eds. New York: Berghahn Books, 1999. 279 pp.
Orientpolitik, Value, and Civilisation: Franz Baermann Steiner Selected Writings, vol. 2. Jeremy Adler and Richard Fardon. eds. New York: Berghahn Books, 1999. 296 pp. 相似文献
Marcel Mauss:. Centenary Tribute. Wendy James and N. J. Allen. eds. New York: Berghahn Press, 1998. 260 pp.
Taboo, Truth, and Religion: Franz Baermann Steiner Selected Writings, vol. 1. Jeremy Adler and Richard Fardon. eds. New York: Berghahn Books, 1999. 279 pp.
Orientpolitik, Value, and Civilisation: Franz Baermann Steiner Selected Writings, vol. 2. Jeremy Adler and Richard Fardon. eds. New York: Berghahn Books, 1999. 296 pp. 相似文献
2.
Donatella Zona Peter M. Lafleur Koen Hufkens Beniamino Gioli Barbara Bailey George Burba Eugénie S. Euskirchen Jennifer D. Watts Kyle A. Arndt Mary Farina John S. Kimball Martin Heimann Mathias Göckede Martijn Pallandt Torben R. Christensen Mikhail Mastepanov Efrén López-Blanco Albertus J. Dolman Roisin Commane Charles E. Miller Josh Hashemi Lars Kutzbach David Holl Julia Boike Christian Wille Torsten Sachs Aram Kalhori Elyn R. Humphreys Oliver Sonnentag Gesa Meyer Gabriel H. Gosselin Philip Marsh Walter C. Oechel 《Global Change Biology》2023,29(5):1267-1281
Long-term atmospheric CO2 concentration records have suggested a reduction in the positive effect of warming on high-latitude carbon uptake since the 1990s. A variety of mechanisms have been proposed to explain the reduced net carbon sink of northern ecosystems with increased air temperature, including water stress on vegetation and increased respiration over recent decades. However, the lack of consistent long-term carbon flux and in situ soil moisture data has severely limited our ability to identify the mechanisms responsible for the recent reduced carbon sink strength. In this study, we used a record of nearly 100 site-years of eddy covariance data from 11 continuous permafrost tundra sites distributed across the circumpolar Arctic to test the temperature (expressed as growing degree days, GDD) responses of gross primary production (GPP), net ecosystem exchange (NEE), and ecosystem respiration (ER) at different periods of the summer (early, peak, and late summer) including dominant tundra vegetation classes (graminoids and mosses, and shrubs). We further tested GPP, NEE, and ER relationships with soil moisture and vapor pressure deficit to identify potential moisture limitations on plant productivity and net carbon exchange. Our results show a decrease in GPP with rising GDD during the peak summer (July) for both vegetation classes, and a significant relationship between the peak summer GPP and soil moisture after statistically controlling for GDD in a partial correlation analysis. These results suggest that tundra ecosystems might not benefit from increased temperature as much as suggested by several terrestrial biosphere models, if decreased soil moisture limits the peak summer plant productivity, reducing the ability of these ecosystems to sequester carbon during the summer. 相似文献
3.
Ichnology and sedimentology of a tide‐influenced delta in the Ordovician from the northeastern Alborz range of Iran (Kopet Dagh region)
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Aram Bayet‐Goll Carlos Neto de Carvalho 《Lethaia: An International Journal of Palaeontology and Stratigraphy》2016,49(3):327-350
The Middle–Late Ordovician Ghelli Formation in the Kopet Dagh region northeastern Alborz range of Iran is composed of siliciclastic rocks deposited in a variety of turbidite to marginal marine environments (deep marine clastic fan and related environments and prodelta, distal delta front, proximal delta front and distributary channels). The ichnology of the middle member of the Ghelli Formation is here reported. Combined sedimentological and ichnological analysis allows recognition of a tide‐influenced deltaic succession in the middle member of the Ghelli Formation consisting of three main facies associations: lower distributary channels, delta front and prodelta facies. Twenty‐two ichnogenera have been identified in this marginal marine succession: Arenicolites, Arthrophycus, Bergaueria, Chondrites, Conichnus, Cruziana, Cylindrichnus, Didymaulichnus, Diplichnites, Diplocraterion, Helminthopsis, Gyrochorte, Lockeia, Macaronichnus, Monomorphichnus, Palaeophycus, Planolites, Rosselia, Rusophcus, Skolithos, Teichichnus and ?Scolicia. Their distribution is clearly linked with lithofacies and depositional palaeoenvironments. The ichnological analysis reveals that the trace fossil suites developed in these environments indicate low diversity and low to moderate abundance of burrows, poor development of tiering and sporadic distribution. Low ichnodiversity and low bioturbation intensities with higher bioturbation clusters consist of facies‐crossing ichnogenera, and the impoverishment of suspension‐feeding trophic types indicates ‘stressed’, non‐archetypal expression of the Cruziana ichnofacies. The periodic higher intensities of bioturbation due to variations in hydrodynamic regimes of tidal currents reflect the archetypal of the Cruziana ichnofacies (and rare Skolithos ichnofacies). 相似文献
4.
KS Lee RN Kim BH Yoon DS Kim SH Choi DW Kim SH Nam A Kim A Kang KH Park JE Jung SH Chae HS Park 《Bioinformation》2012,8(11):532-534
Recently, next generation sequencing (NGS) technologies have led to a revolutionary increase in sequencing speed and costefficacy. Consequently, a vast number of contigs from many recently sequenced bacterial genomes remain to be accurately mapped and annotated, requiring the development of more convenient bioinformatics programs. In this paper, we present a newly developed web-based bioinformatics program, Bacterial Genome Mapper, which is suitable for mapping and annotating contigs that have been assembled from bacterial genome sequence raw data. By constructing a multiple alignment map between target contig sequences and two reference bacterial genome sequences, this program also provides very useful comparative genomics analysis of draft bacterial genomes. AVAILABILITY: The database is available for free at http://mbgm.kribb.re.kr. 相似文献
5.
6.
Qiang Xu Aram Chang Alexandra Tolia Daniel L. Minor 《Journal of molecular biology》2013,425(2):378-394
Calmodulin (CaM) is an important regulator of Kv7.x (KCNQx) voltage-gated potassium channels. Channels from this family produce neuronal M currents and cardiac and auditory IKS currents and harbor mutations that cause arrhythmias, epilepsy, and deafness. Despite extensive functional characterization, biochemical and structural details of the interaction between CaM and the channel have remained elusive. Here, we show that both apo-CaM and Ca2 +/CaM bind to the C-terminal tail of the neuronal channel Kv7.4 (KCNQ4), which is involved in both hearing and mechanosensation. Interactions between apo-CaM and the Kv7.4 tail involve two C-terminal tail segments, known as the A and B segments, whereas the interaction between Ca2 +/CaM and the Kv7.4 C-terminal tail requires only the B segment. Biochemical studies show that the calcium dependence of the CaM:B segment interaction is conserved in all Kv7 subtypes. X-ray crystallographic determination of the structure of the Ca2 +/CaM:Kv7.4 B segment complex shows that Ca2 +/CaM wraps around the Kv7.4 B segment, which forms an α-helix, in an antiparallel orientation that embodies a variation of the classic 1-14 Ca2 +/CaM interaction motif. Taken together with the context of prior studies, our data suggest a model for modulation of neuronal Kv7 channels involving a calcium-dependent conformational switch from an apo-CaM form that bridges the A and B segments to a Ca2 +/CaM form bound to the B-helix. The structure presented here also provides a context for a number of disease-causing mutations and for further dissection of the mechanisms by which CaM controls Kv7 function. 相似文献
7.
Applications of a new subspace clustering algorithm (COSA) in medical systems biology 总被引:1,自引:0,他引:1
Doris Damian Matej Orešič Elwin Verheij Jacqueline Meulman Jerome Friedman Aram Adourian Nicole Morel Age Smilde Jan van der Greef 《Metabolomics : Official journal of the Metabolomic Society》2007,3(1):69-77
A novel clustering approach named Clustering Objects on Subsets of Attributes (COSA) has been proposed (Friedman and Meulman,
(2004). Clustering objects on subsets of attributes. J. R. Statist. Soc. B 66, 1–25.) for unsupervised analysis of complex data sets. We demonstrate its usefulness in medical systems biology studies.
Examples of metabolomics analyses are described as well as the unsupervised clustering based on the study of disease pathology
and intervention effects in rats and humans. In comparison to principal components analysis and hierarchical clustering based
on Euclidean distance, COSA shows an enhanced capability to trace partial similarities in groups of objects enabling a new
discovery approach in systems biology as well as offering a unique approach to reveal common denominators of complex multi-factorial
diseases in animal and human studies.
Doris Damian, Matej Orešič, and Elwin Verheij contributed equally to this work. 相似文献
8.
Macrophages are a major cellular component of innate immunity and are mainly known to have phagocytic activity. In the tumor microenvironment (TME), they can be differentiated into tumor-associated macrophages (TAMs). As the most abundant immune cells in the TME, TAMs promote tumor progression by enhancing angiogenesis, suppressing T cells and increasing immunosuppressive cytokine production. N-myc downstream-regulated gene 2 (NDRG2) is a tumor suppressor gene, whose expression is down-regulated in various cancers. However, the effect of NDRG2 on the differentiation of macrophages into TAMs in breast cancer remains elusive. In this study, we investigated the effect of NDRG2 expression in breast cancer cells on the differentiation of macrophages into TAMs. Compared to tumor cell-conditioned medium (TCCM) from 4T1-mock cells, TCCM from NDRG2-overexpressing 4T1 mouse breast cancer cells did not significantly change the morphology of RAW 264.7 cells. However, TCCM from 4T1-NDRG2 cells reduced the mRNA levels of TAM-related genes, including MR1, IL-10, ARG1 and iNOS, in RAW 264.7 cells. In addition, TCCM from 4T1-NDRG2 cells reduced the expression of TAM-related surface markers, such as CD206, in peritoneal macrophages (PEM). The mRNA expression of TAM-related genes, including IL-10, YM1, FIZZ1, MR1, ARG1 and iNOS, was also downregulated by TCCM from 4T1-NDRG2 cells. Remarkably, TCCM from 4T1-NDRG2 cells reduced the expression of PD-L1 and Fra-1 as well as the production of GM-CSF, IL-10 and ROS, leading to the attenuation of T cell-inhibitory activity of PEM. These data showed that compared with TCCM from 4T1-mock cells, TCCM from 4T1-NDRG2 cells suppressed the TAM differentiation and activation. Collectively, these results suggest that NDRG2 expression in breast cancer may reduce the differentiation of macrophages into TAMs in the TME. 相似文献
9.
Aram A. Yengoyan 《American anthropologist》1998,100(1):181-184
Arguments about Aborigines: Australia and the Evolution of Social Anthropology, L. R. Hiatt Cambridge: Cambridge University Press, 1996. 225 pp.
What the Bones Say: Tasmanian Aborigines, Science, and Domination. John J. Cove. Ottawa, Canada: Carleton University Press, 1995. 221 pp. 相似文献
What the Bones Say: Tasmanian Aborigines, Science, and Domination. John J. Cove. Ottawa, Canada: Carleton University Press, 1995. 221 pp. 相似文献
10.
Synergistic Impact of Solvent and Polymer Additives on the Film Formation of Small Molecule Blend Films for Bulk Heterojunction Solar Cells
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Caitlin McDowell Maged Abdelsamie Kui Zhao Detlef‐M. Smilgies Guillermo C. Bazan Aram Amassian 《Liver Transplantation》2015,5(18)
The addition of polystyrene (PS), a typical insulator, is empirically shown to increase the power conversion efficiencies (PCEs) of a solution‐deposited bulk heterojunction (BHJ) molecular blend film used in solar cell fabrication: p‐DTS(FBTTh2)2/PC71BM. The performance is further improved by small quantities of diiodooctane (DIO), an established solvent additive. In this study, how the addition of PS and DIO affects the film formation of this bulk heterojunction blend film are probed via in situ monitoring of absorbance, thickness, and crystallinity. PS and DIO additives are shown to promote donor crystallite formation on different time scales and through different mechanisms. PS‐containing films retain chlorobenzene solvent, extending evaporation time and promoting phase separation earlier in the casting process. This extended time is insufficient to attain the morphology for optimal PCE results before the film sets. Here is where the presence of DIO comes into play: its low vapor pressure further extends the time scale of film evolution and allows for crystalline rearrangement of the donor phase long after casting, ultimately leading to the best BHJ organization. 相似文献