6,316 research outputs found
Neuronal representation of visual motion and orientation in the fly medulla
No full textSpalthoff C, Gerdes R, Kurtz R. Neuronal representation of visual motion and orientation in the fly medulla. Frontiers in Neural Circuits. 2012;6:72.In insects, the first extraction of motion and direction clues from local brightness modulations is thought to take place in the medulla. However, whether and how these computations are represented in the medulla stills remain widely unknown, because electrical recording of the neurons in the medulla is difficult. As an effort to overcome this difficulty, we employed local electroporation in vivo in the medulla of the blowfly (Calliphora vicina) to stain small ensembles of neurons with a calcium-sensitive dye. We studied the responses of these neuronal ensembles to spatial and temporal brightness modulations and found selectivity for grating orientation. In contrast, the responses to the two opposite directions of motion of a grating with the same orientation were similar in magnitude, indicating that strong directional selectivity is either not present in the types of neurons covered by our data set, or that direction-selective signals are too closely spaced to be distinguished by our calcium imaging. The calcium responses also showed a bell-shaped dependency on the temporal frequency of drifting gratings, with an optimum higher than that observed in one of the subsequent processing stages, i.e., the lobula plate. Medulla responses were elicited by on- as well as off-stimuli with some spatial heterogeneity in the sensitivity for “on” and “off”, and in the polarity of the responses. Medulla neurons thus show similarities to some established principles of motion and edge detection in the vertebrate visual system
Dual citizenship as a path-dependent process
No full textFaist T, Gerdes J, Rieple B. Dual citizenship as a path-dependent process. COMCAD Arbeitspapiere - working papers, 7. Bielefeld: COMCAD - Center on Migration, Citizenship and Development; 2004
Ad Dignissimam Salutaremqve Passionis Christi Considerationem In Actu Oratorio-Valedictorio D. Februarii MDCCVIII. Hora Instituendam Nobilissimos Amplissimosque Musarum Maecenates, ... / invitat M. Godofrid. Steinbrecherus, Illustris Schol. Torgaviens. Rector [Scribeb. Torgav. A. O. R. Die XV. Kal. Martii M. DCC VIII.]
No full textAutopsie nach dem Ex. der ULB Sachsen-AnhaltVorlageform des Erscheinungsvermerks: Wittenbergæ, Litteris Christiani Gerdesii.Erscheinungsjahr wurde dem Textende entnomme
Theses Ivris Romani Atqve Germanici / Qvas Praeside D. Georgio Stephano Wiesandio Professore Institvtionvm Ordinario Cvriae Provincialis Scabinatvs Atqve Collegii Ivreconsvltorvm Assessore Die IV. April. A. S. R. MDCCLXXV. ... Pvblica Diseptatione Tvebitvr Christian. Lucas Cranach Bvdissa-Lvsatvs
No full textWittenberg, Univ., Jur. Diss., 1775Autopsie nach Exemplar der ULB Sachsen-AnhaltVorlageform des Erscheinungsvermerks: Vitembergae Ex Officina Gerdesina
Theses Ivris Romani / Qvas Praeside D. Georgio Stephano Wiesandio Professore Institvtionvm Ordinario Cvriae Provincialis Scabinatvs Atqve Collegii Ivre Consvltorvm Assessore Die XXVIII. Martii A. S. R. MDCCLXXV. ... Ad Disceptandvm Propoditvrvs Est Iacob. Ehrenfried Weber Bvdissa-Lvsatvs
No full textWittenberg, Univ., Jur. Diss., 1775Autopsie nach Exemplar der ULB Sachsen-AnhaltVorlageform des Erscheinungsvermerks: Vitembergae Ex Officina Gerdesiana
Lectori Benevolo Salutem Plurimam Dicit, Eundemqve Ad Orationem Inauguralem Amplissimi Honorum Theologicorum Candidati Reverenter, Et Officiose, Invitat Gottlieb VVernsdorfius, SS. Theol. Doct. & Prof. Publ. Ordin. Ædis OO. SS. Præpositus, Alumn. Saxo-Electoral. Inspector, Collegiique sui h. t. Decanus : [P. P. Dom. Lætare A. R. S. MD CC XII.]
No full textFingerprint nach Ex. der Bibl. der Franckeschen Stiftungen zu Halle, der SBB und der ULB Sachsen-AnhaltVorlageform des Kolophons: Vitembergæ, Litteris Christiani Gerdesii. - Erscheinungsjahr nach Datierung am Ende des Textes bestimm
Beschreiben und/oder Bewerten. Zur Einführung
No full textAhrens J, Beer R, Bittlingmayer UH, Gerdes J. Beschreiben und/oder Bewerten. Zur Einführung. In: Ahrens J, Beer R, Bittlingmayer UH, Gerdes J, eds. Beschreiben und/oder Bewerten I. Normativität in sozialwissenschaftlichen Forschungsfeldern. Münsteraner Schriften zur Soziologie. Vol 1. Münster: LIT; 2008: 9-74
Reseña de "From Ethnomathematics to art-design matrices and cyclic matrices" de Paulus Gerdes
No full textIn this review, we present the ethnomathematics investigations undertaken in the last three decades by Paulus Gerdes, a Mozambique mathematics educator. The author presents a variety of discussions with several examples that explains the relationship of mathematics to human activities. We present, among other things, the cyclic matrices and its interrelationships with the African cultural contexts, undoing the erroneous impression that mathematics can be seen disconnected from the feature, which makes the individuals in their socio-cultural environments. Gerdes shows us that there's mathematics in different cultures and this helps us to realize the beauty of the symmetries and patterns, in addition to allowing depth between mathematics and human actions in the art
Torgaviensium Votivi Applausus, Quibus Virum Juvenem Per-Eximum Atqve Doctissimum. Dominum Joh. Christianum Lieberwirth, Torgaviensem, S. S. Theologiæ Cultorem, Cum Homores Magistrales In Celeberrima Vitembergensium Academia Die XXIX Aprilis A. R. S. MDCCVI More institutoque Majorum capesseret, prosequebantur Patroni, Fautores Atque Amici
No full textGlückwunschgedichte auf Johann Christian Lieberwirth, Theologe, zur Magisterwürde, 29. Apr. 1706Autopsie nach dem Ex. der ULB Sachsen-AnhaltVorlageform des Erscheinungsvermerks: Vitembergæ, Typis Christiani Gerdesii
Book review: “From Ethnomathematics to art-design matrices and cyclic matrices” – Paulus Gerdes – Ed. UNESP, 2010
No full textIn this review, we present the ethnomathematics investigations undertaken in the last three decades by Paulus Gerdes, a Mozambique mathematics educator. The author presents a variety of discussions with several examples that explains the relationship of mathematics to human activities. We present, among other things, the cyclic matrices and its interrelationships with the African cultural contexts, undoing the erroneous impression that mathematics can be seen disconnected from the feature, which makes the individuals in their socio-cultural environments. Gerdes shows us that there's mathematics in different cultures and this helps us to realize the beauty of the symmetries and patterns, in addition to allowing depth between mathematics and human actions in the art
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