43,640 research outputs found
Varia carmina
No full text[Ergänzungen von Johann Bergmann]Impressum aus Kolophon: "... foelici fine consummatum Basileae opera & impensis Iohannis Bergman De Olpe Kalendas Maiis Anni &c. xcviii."Mit HolzschnittenV.d.Haegen: mit Beigaben von Thomas Beccadelli, S. Brant und J. Locher ; mit Zusätzen von Joh. BergmannDatum gemäss v.d.Haegen: 1.5. - (nach) 1.9.1496Sometimes found with 2 additional signatures, m and n the latter having the date 1 Sept. 1498 (Goff). GW records a variant (Pell 2187B). WoodcutsSignaturen: A-D⁸, E⁴F⁸-G⁴H⁸, I⁴, k⁴, a⁸, bc⁴, d-h⁸, i⁴, k-l⁸, m-n⁴, []
Kruppel-like factor 4 expression in normal and pathological human testes
No full textKrüppel-like factor 4 (KLF4) is a transcription factor involved in many cellular and developmental processes such as terminal differentiation of cells and carcinogenesis. Mice lacking KLF4 die post-natally due to skin barrier deficiencies and exhibit several additional cellular defects. The adult rodent testis expresses high levels of Klf4 mRNA. Using in situ hybridization, we previously localized most of the Klf4 mRNA to round spermatids in mice. Moreover, in rodent Sertoli cells, Klf4 is strongly inducible by FSH. Here, we show by northern blot analysis that the human testis also strongly expresses KLF4. Applying immunohistochemistry, we localized KLF4 protein to the nuclei of round spermatids during normal spermatogenesis stages II–IV. Analysing round spermatid maturation arrests, strong cytoplasmic staining could be seen in two samples. We failed to detect KLF4 in human Sertoli cells. Most human Leydig cells expressed KLF4 at high levels in the nucleus. However, some individual Leydig cells lacked KLF4, suggesting different functional states of the Leydig cells. The strong expression of KLF4 in the human testis and the importance of KLF4 in several mouse tissues suggest a significant role for KLF4 in the human testis. A first hint at a role for KLF4 during spermiogenesis could be the altered subcellular localization of the protein during arrested spermiogenesis.Behr, C. Deller, M. Godmann, T. Müller, M. Bergmann, R. Ivell and K. Stege
K-theory for group C*-algebras
No full textThese notes are based on a lecture course given by the first author in the Sedano Winter School on K-theory held in Sedano, Spain, on January 22-27th of 2007. They aim at introducing K-theory of C*-algebras, equivariant K-homology and KK-theory in the context of the Baum-Connes conjectur
Pollen and Pollinosis
No full textPollen grains only represent a small fraction of the total amount of the viable biological particles present in the air, but pollen are the most important aeroallergens in the outdoor environment. The analysis of pollen has traditionally been carried out by microscopy, which can be traced back to the 17th century. Modern advances in molecular analysis could improve information for allergy sufferers and health care professionals. Pollen allergy (pollinosis) was first described in the 19th century. The prevalence of respiratory diseases increased dramatically during the latter part of the 20th century and millions of individuals are now affected. A number of scientists devised equipment to examine airborne biological particles during the 19th century, but aerobiological monitoring only became standardized during the 20th century. Airborne pollen are routinely monitored in many parts of the world, such as North America and Europe, and the first limited network has also been created for monitoring airborne allergen concentrations. Monitoring of the environment is often based on a combination of measurements and model results. Source-based models can increase our knowledge of airborne pollen because they can explain situations and processes that are almost impossible to understand using observations alone
Grounding the Simulation of Iconic Gestures in Gesture Typology
No full textBergmann K, Kopp S, Rieser H. Grounding the Simulation of Iconic Gestures in Gesture Typology. In: Efthimiou E, Kouroupetroglou G, eds. Proceedings of the 9th International Gesture Workshop: Gestures in Embodied Communication and Human-Computer Interaction. Berlin/Heidelberg, Germany: Springer; 2011: 33-36
Towards an Architecture for Aligned Speech and Gesture Production
No full textKopp S, Bergmann K. Towards an Architecture for Aligned Speech and Gesture Production. In: Pelachaud C, André E, Chollet G, Karpouzis K, Pelé D, eds. Proceedings of the 7th International Conference on Intelligent Virtual Agents. Berlin/Heidelberg, Germany: Springer; 2007: 389-390
Search for eta(c) decays into pi pi and K(K)over-bar
No full textUsing 58 million J/psi) events taken with the BESII detector, a search for eta(c) CP violating decays into pi pi and K (K) over bar has been performed. No clear 77, signal is observed, and upper limits for B(eta(c) -> pi pi) and B(eta(c) -> K (K) over bar) are given at the 90% confidence level, B(J/psi -> gamma eta(c)) center dot B(eta(c) -> pi(+)pi(-)) < 1.1 x 10(-5), B(J/psi -> gamma eta(c)) center dot B(eta(c) -> pi(0)pi(0)) < 0.71 x 10(-5), B(J/psi -> gamma(eta c)) center dot B(eta(c) -> K+K-) < 0.96 x 10(-5), and B(J/psi -> gamma eta(c)) center dot B(eta(c) (KSKS0)-K-0) < 0.53 x 10(-5).Physics, Particles & FieldsSCI(E)1ARTICLE2337-3414
The dynamics of single spike-evoked adenosine release in the cerebellum
No full textThe purine adenosine is a potent neuromodulator in the brain, with roles in a number
of diverse physiological and pathological processes. Modulators such as adenosine are difficult
to study as once released they have a diffuse action (which can affect many neurones) and,
unlike classical neurotransmitters, have no inotropic receptors. Thus rapid postsynaptic currents
(PSCs) mediated by adenosine (equivalent to mPSCs) are not available for study. As a result
the mechanisms and properties of adenosine release still remain relatively unclear. We have
studied adenosine release evoked by stimulating the parallel fibres in the cerebellum. Using
adenosine biosensors combined with deconvolution analysis and mathematical modelling, we
have characterised the release dynamics and diffusion of adenosine in unprecedented detail.
By partially blocking K+ channels, we were able to release adenosine in response to a single
stimulus rather than a train of stimuli. This allowed reliable sub-second release of reproducible
quantities of adenosine with stereotypic concentration waveforms that agreed well with predictions
of a mathematical model of purine diffusion. We found no evidence for ATP release
and thus suggest that adenosine is directly released in response to parallel fibre firing and does
not arise from extracellular ATP metabolism. Adenosine release events showed novel short-term
dynamics, including facilitated release with paired stimuli at millisecond stimulation intervals
but depletion-recovery dynamics with paired stimuli delivered over minute time scales. These
results demonstrate rich dynamics for adenosine release that are placed, for the first time, on a
quantitative footing and show strong similarity with vesicular exocytosis
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