A hypothalamic channel-system in the inferior lobes of a trigger-fish (Rhinecanthus aculeatus, Balistidae)

In the course of a general investigation of the optic system in some trigger-fishes, a hypothalamic, ventricular channel-system with pores, leading to the outside of the brain, has been discovered in the inferior lobes ofRhinecanthus aculeatus (Balistidae). A description of the morphological relations of the channel-system to the blood-vessel-supply and the cranium suggests that the organ-systems involved form a functional unit. The possibility of a hormone-producing system is discussed in the light of physiological and ecological aspects

Esparsette (Onobrychis viciifolia) als mögliche Futterpflanze zur Kontrolle von Magen-Darm-Strongyliden bei Schafen

In der Schaf- und Ziegenhaltung stellt der Befall mit Magen-Darm-Strongyliden (MDS) einen wesentlichen Problemfaktor für die Tiergesundheit dar. Klinische und subklinische Erkrankungen können von erheblicher wirtschaftlicher Relevanz sein. Eine zunehmende Resistenzentwicklung gegen seit langem eingesetzte Anthelminthika hat derzeit einen intensivierten Einsatz dieser Wirkstoffe zur Folge und verschärft das Problem somit zusätzlich. Die Entwicklung und Bereitstellung komplementärer Kontrollstrategien könnte zu einer erheblichen Reduktion des Anthelminthika-Einsatzes beitragen. Eine mögliche Strategie stellt der Einsatz tanninhaltiger Futterpflanzen dar. Wir beschreiben Ergebnisse aus einem in vivo Versuch zur antiparasitischen Wirkung von Esparsettenheu und Esparsettensilage (6,2 % und 4,4 % Tannine / Trockensubstanz) gegen Haemonchus contortus und Cooperia curticei in experimentell infizierten Lämmern. Nach 16-tägiger Fütterung mit Esparsettenheu war die H. contortus Wurmbürde im Vergleich zu einer isoproteisch und isoenergetisch gefütterten Kontrollgruppe (0,1 % Tannine / Trockensubstanz) um 53 % reduziert (P < 0,05). Es konnte gezeigt werden, dass Lämmer, die mit Esparsettenheu gefüttert wurden, bereits 10 Tage nach Versuchsbeginn 44 % (P < 0,05) weniger H. contortus Eier pro Gramm Kot (EpG) ausschieden als die Kontrolltiere. Bei Versuchsende (16 Tage nach Fütterungsbeginn) war die H. contortus Eiausscheidung im Vergleich zur Kontrolle um 58 % reduziert (P < 0,01). Die Tagesgewichtszunahme der Lämmer in der Esparsettenheu-Gruppe war im Vergleich zur Kontrollgruppe tendenziell besser (163 g/Tag und 96 g/Tag; P = 0,07). Die Fütterung mit Esparsettensilage reduzierte die H. contortus Eiausscheidung verglichen mit der Kontrolle um 48 %. Dieses Resultat war allerdings nicht signifikant (P = 0,075). Im Vergleich zu den Kontrollgruppen wurde die C. curticei Eiausscheidung durch Esparsettenheu um 74 % (P < 0,001) und durch Esparsettensilage um 81 % (P < 0,001) reduziert. Es handelt sich bei dieser Studie um die erste, welche die für den Praxiseinsatz wichtige Verwendung einer konservierten, tanninhaltigen Futterpflanze gezielt gegen H. contortus und C. curticei untersucht

Stochasticity from function -- why the Bayesian brain may need no noise

An increasing body of evidence suggests that the trial-to-trial variability of spiking activity in the brain is not mere noise, but rather the reflection of a sampling-based encoding scheme for probabilistic computing. Since the precise statistical properties of neural activity are important in this context, many models assume an ad-hoc source of well-behaved, explicit noise, either on the input or on the output side of single neuron dynamics, most often assuming an independent Poisson process in either case. However, these assumptions are somewhat problematic: neighboring neurons tend to share receptive fields, rendering both their input and their output correlated; at the same time, neurons are known to behave largely deterministically, as a function of their membrane potential and conductance. We suggest that spiking neural networks may, in fact, have no need for noise to perform sampling-based Bayesian inference. We study analytically the effect of auto- and cross-correlations in functionally Bayesian spiking networks and demonstrate how their effect translates to synaptic interaction strengths, rendering them controllable through synaptic plasticity. This allows even small ensembles of interconnected deterministic spiking networks to simultaneously and co-dependently shape their output activity through learning, enabling them to perform complex Bayesian computation without any need for noise, which we demonstrate in silico, both in classical simulation and in neuromorphic emulation. These results close a gap between the abstract models and the biology of functionally Bayesian spiking networks, effectively reducing the architectural constraints imposed on physical neural substrates required to perform probabilistic computing, be they biological or artificial

Understanding Variation in Sets of N-of-1 Trials.

A recent paper in this journal by Chen and Chen has used computer simulations to examine a number of approaches to analysing sets of n-of-1 trials. We have examined such designs using a more theoretical approach based on considering the purpose of analysis and the structure as regards randomisation that the design uses. We show that different purposes require different analyses and that these in turn may produce quite different results. Our approach to incorporating the randomisation employed when the purpose is to test a null hypothesis of strict equality of the treatment makes use of Nelder's theory of general balance. However, where the purpose is to make inferences about the effects for individual patients, we show that a mixed model is needed. There are strong parallels to the difference between fixed and random effects meta-analyses and these are discussed

Studenten am Hausärzte-Kongress in Arosa

Medizinstudenten an einem Hausärztekongress? Vor 10 Jahren noch undenkbar, heute eine Realität. Dieser Beitrag schildert kurz die Entwicklung des «Studentenprojekts » am H ausärzte-Kongress Arosa und zeigt, dass ein innovatives Weiterbildungsformat auch bei angehenden Ärzten Interesse wecken kann

Transmission resonances and supercritical states in a one dimensional cusp potential

We solve the two-component Dirac equation in the presence of a spatially one dimensional symmetric cusp potential. We compute the scattering and bound states solutions and we derive the conditions for transmission resonances as well as for supercriticality.Comment: 10 pages. Revtex 4. To appear in Phys Rev.

Neonatal immune tolerance induction to allow long-term studies with an immunogenic therapeutic monoclonal antibody in mice

The purpose of this study is to test the feasibility of neonatal immune tolerance induction in mice to enable long-term pharmacokinetic studies with immunogenic therapeutic monoclonal antibodies (mAb). Neonatal immune tolerance was induced by transfer of a mAb to neonatal mice via colostrum from nursing mother mice treated with two subcutaneous doses of a tolerogen starting within the first 24 h after delivery. Adalimumab and efalizumab were administered as tolerogens at various dose levels. Tolerance induction was evaluated in the offspring after reaching adulthood at 8 weeks of age. After a single intravenous injection of the same mAb as used for tolerance induction, the pharmacokinetics of the mAb and formation of anti-drug antibodies (ADA) in plasma were assessed using ELISA. Tolerance induction to adalimumab was achieved in a maternal dose-dependent manner. Adalimumab immune-tolerant offspring showed a slower adalimumab clearance (4.24 ± 0.32 mL/day/kg) as compared to the control group (12.09 ± 3.81 mL/day/kg). In the control group, accelerated clearance started 7 days after adalimumab dosing, whereas immune- tolerant offspring showed a log-linear terminal concentration-time course. In the offspring, the absence of predose ADA levels was indicative of successful tolerance induction. The second test compound efalizumab was not immunogenic in mice under our experimental conditions. Overall, the present study demonstrated the suitability of neonatal immune tolerance induction for a 4-week single dose study in adult mice with a human therapeutic mAb that is otherwise immunogenic in laboratory animals

Charge order at the frontier between the molecular and solid states in Ba3NaRu2O9

We show that the valence electrons of Ba3NaRu2O9, which has a quasi-molecular structure, completely crystallize below 210 K. Using an extended Hubbard model, we show that the charge ordering instability results from long-range Coulomb interactions. However, orbital ordering, metal-metal bonding and formation of a partial spin gap enforce the magnitude of the charge separation. The striped charge order and frustrated hcp lattice of Ru2O9 dimers lead to competition with a quasi-degenerate charge-melted phase under photo-excitation at low temperature. Our results establish a broad class of simple metal oxides as models for emergent phenomena at the border between the molecular and solid states.Comment: Minor changes, with supporting information. To appear in Phys. Rev. Let