514 research outputs found
Geosocial Graph-Based Community Detection
We apply spectral clustering and multislice modularity optimization to a Los
Angeles Police Department field interview card data set. To detect communities
(i.e., cohesive groups of vertices), we use both geographic and social
information about stops involving street gang members in the LAPD district of
Hollenbeck. We then compare the algorithmically detected communities with known
gang identifications and argue that discrepancies are due to sparsity of social
connections in the data as well as complex underlying sociological factors that
blur distinctions between communities.Comment: 5 pages, 4 figures Workshop paper for the IEEE International
Conference on Data Mining 2012: Workshop on Social Media Analysis and Minin
Multislice Modularity Optimization in Community Detection and Image Segmentation
Because networks can be used to represent many complex systems, they have
attracted considerable attention in physics, computer science, sociology, and
many other disciplines. One of the most important areas of network science is
the algorithmic detection of cohesive groups (i.e., "communities") of nodes. In
this paper, we algorithmically detect communities in social networks and image
data by optimizing multislice modularity. A key advantage of modularity
optimization is that it does not require prior knowledge of the number or sizes
of communities, and it is capable of finding network partitions that are
composed of communities of different sizes. By optimizing multislice modularity
and subsequently calculating diagnostics on the resulting network partitions,
it is thereby possible to obtain information about network structure across
multiple system scales. We illustrate this method on data from both social
networks and images, and we find that optimization of multislice modularity
performs well on these two tasks without the need for extensive
problem-specific adaptation. However, improving the computational speed of this
method remains a challenging open problem.Comment: 3 pages, 2 figures, to appear in IEEE International Conference on
Data Mining PhD forum conference proceeding
Le kitâb-khâna de ‘Abd al-‘Azîz Khân (1645-1680) et le mécénat de la peinture à Boukhara
Il y a quelques années encore, la peinture de l’école de Boukhara au XVIIe siècle était pratiquement inconnue. Peut-être l’une des premières études scientifiques de cette école a-t-elle été fournie par le descriptif de la Khamsa de 1671, conservée à Dublin, dans le catalogue publié par Arberry et ses collaborateurs en 1961. Du reste, il est étonnant de constater le grand nombre de manuscrits de Boukhara acquis par Alfred Chester Beatty entre 1920 et 1965, époque pendant laquelle ces manuscrit..
Farhad le peintre : à propos des ateliers de peinture de Boukhara à l’époque de ‘Abd al-‘Aziz Khan, 1645-1680
Voici quelques années, un article écrit par O.F. Akimushkin et A. A. Ivanov donnait à connaître l’école de peinture de Boukhara à travers un texte jusque-là quasiment inconnu des historiens de l’art, le Moḥiṭ al-tavârikh de Mohammad Amin Bokhari. Cet article fournit – outre la traduction du passage concernant les ateliers de peinture à l’époque de Sobhan Qoli Khan (1680-1702) – quantité de documents concernant la peinture et les arts du livre à Boukhara dans la deuxième moitié du XVIIe siècle..
Papiers de l'Iran et de l'Inde : archéologies impalpables de témoins discrets
Actes de la journée d’étude du 22 septembre 2017, organisée par L’HiCSA (Histoire Culturelle et Sociale de l’Art) de l'Université Paris I Panthéon-Sorbonne et le département des restaurateurs de l'Institut National du Patrimoine.International audienc
Farhad le peintre : à propos des ateliers de peinture de Boukhara à l’époque de ‘Abd al-‘Aziz Khan, 1645-1680
Voici quelques années, un article écrit par O.F. Akimushkin et A. A. Ivanov donnait à connaître l’école de peinture de Boukhara à travers un texte jusque-là quasiment inconnu des historiens de l’art, le Moḥiṭ al-tavârikh de Mohammad Amin Bokhari. Cet article fournit – outre la traduction du passage concernant les ateliers de peinture à l’époque de Sobhan Qoli Khan (1680-1702) – quantité de documents concernant la peinture et les arts du livre à Boukhara dans la deuxième moitié du XVIIe siècle..
Derek J. Content, Ruby, Sapphire & Spinel: An Archaeological, Textual and Cultural Study, Part I: Text, Part II: The Babar-Content Collection
Présenté en deux volumes, cet ouvrage prend pour fondement l’étude de la collection de bijoux et de pierres précieuses réunie par l’auteur et par Riaz Babar (The Babar-Content Collection). Derek Content est par ailleurs connu non seulement en tant que marchand et expert en pierres précieuses, mais aussi comme collectionneur de camées et intailles antiques (voir Martin Henig, The Content Family Collection of Ancient Cameos, Oxford, Ashmoleam Museum, 1990). Le premier volume (intitulé Text) est..
Novel associations in disorders of sex development: findings from the I-DSD registry
Context:
The focus of care in disorders of sex development (DSD) is often directed to issues related to sex and gender development. In addition, the molecular etiology remains unclear in the majority of cases.<p></p>
Objective:
To report the range of associated conditions identified in the international DSD (I-DSD) Registry.<p></p>
Design, Setting, and Patients:
Anonymized data were extracted from the I-DSD Registry for diagnosis, karyotype, sex of rearing, genetic investigations, and associated anomalies. If necessary, clarification was sought from the reporting clinician.<p></p>
Results:
Of 649 accessible cases, associated conditions occurred in 168 (26%); 103 (61%) cases had one condition, 31 (18%) had two conditions, 20 (12%) had three conditions, and 14 (8%) had four or more conditions. Karyotypes with most frequently reported associations included 45,X with 6 of 8 affected cases (75%), 45,X/46,XY with 19 of 42 cases (45%), 46,XY with 112 of 460 cases (24%), and 46,XX with 27 of 121 cases (22%). In the 112 cases of 46,XY DSD, the commonest conditions included small for gestational age in 26 (23%), cardiac anomalies in 22 (20%), and central nervous system disorders in 22 (20%), whereas in the 27 cases of 46,XX DSD, skeletal and renal anomalies were commonest at 12 (44%) and 8 (30%), respectively. Of 170 cases of suspected androgen insensitivity syndrome, 19 (11%) had reported anomalies and 9 of these had confirmed androgen receptor mutations.<p></p>
Conclusions:
Over a quarter of the cases in the I-DSD Registry have an additional condition. These associations can direct investigators toward novel genetic etiology and also highlight the need for more holistic care of the affected person.<p></p>
T84-intestinal epithelial exosomes bear MHC class II/peptide complexes potentiating antigen presentation by dendritic cells: Function of intestinal epithelial exosomes
International audienceBackground and aims: Intestinal epithelial cells release antigen presenting vesicles (exosomes) bearing MHC class II/peptide complexes stimulating specific immune responses in vivo. To further characterize the role of human epithelial exosomes in antigen presentation, their capacity to load antigenic peptides, to bind immune target cells and to induce T cell activation was analyzed in vitro. Methods: The capacity of exosomes derived from the HLA-DR4 expressing, intestinal epithelial cell line T84, to load the HLA-DR4-specific peptide 3H-HSA 64-76 and to activate a HLA-DR4-restricted T cell hybridoma, was tested in the presence or absence of human monocyte-derived dendritic cells (DCs). Interaction of FITC-labeled exosomes with T cells and DCs was analyzed by flow cytometry and confocal microscopy. Results: T84-derived exosomes, enriched in CD9, CD81, CD82 and A33 antigen, were capable of binding specifically HSA 64-76 peptide on HLA-DR4 molecules and of interacting preferentially with DCs. HSA-loaded exosomes were unable to activate the T cell hybridoma directly, but induced a productive T cell activation through DCs. When HSA peptide was bound to exosomal HLA-DR4 molecules instead of in a soluble form, the threshold of peptide presentation by DCs was markedly decreased (x10-3). Conclusions: Exosomes released by intestinal epithelial cells bear exogenous peptides complexed to MHC class II molecules and interact preferentially with DCs, strongly potentiating peptide presentation to T cells. Epithelial exosomes constitute a powerful link between luminal antigens and local immune cells by mediating the transfer of tiny amounts of luminal antigenic information and facilitating immune surveillance at mucosal surfaces
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