A tailored biocompatible neural interface for long term monitoring in neural networks

Neural interface electrodes that can record from neurons in the brain for long periods of time will be of great importance to unravel how the brain accomplishes its functions. However, current electrodes usually cause significant glia reactions and loss of neurons within the adjacent brain parenchyma. To address this challenge, a novel, polymer-based neural probe, with protrusions tailored to the target tissue, was developed to investigate which probe properties affect the development of a glial scar and neuronal cell death surrounding probes. After many cycles of testing – refinements, promising recordings of neural activity were obtained in both cerebellum and cortex cerebri (papers I-III). In paper IV, we evaluated the importance of mechanical flexibility and demonstrated that probe flexibility has a significant impact on the astroglial scar, but not on the loss of neurons nearby. Moreover, by embedding the dummy probes in a gelatin matrix that dissolves shortly following implantation, neuronal cell death surrounding chronically (6 weeks) implanted electrodes was, for the first time, abolished. In paper V, sensory processing in primary somatosensory cortex during an episode of hyperalgesia was monitored using implanted neural interfaces in order to further evaluate the probe functionality and usefulness in neurophysiological research. By tracking the development of primary and secondary hyperalgesia as well as allodynia in the sensory cortex, we demonstrate the usefulness of our new neural interface and its capability to differentially and simultaneously record neural signals in different cortical laminae in awake freely moving animals

The discrepancy between dynamical and theoretical mass in the triplet-system 2MASS J10364483+1521394

We combine new Lucky Imaging astrometry from NTT/AstraLux Sur with already published astrometry from the AstraLux Large M-dwarf Multiplicity Survey to compute orbital elements and individual masses of the 2MASS J10364483+1521394 triple system belonging to the Ursa-Major moving group. The system consists of one primary low-mass M-dwarf orbited by two less massive companions, for which we determine a combined dynamical mass of $M_{\rm{B}+\rm{C}}= 0.48 \pm 0.14\ M_\odot$. We show from the companions relative motions that they are of equal mass (with a mass ratio of$1.00 \pm 0.03$), thus$0.24 \pm 0.07\ M_\odot$individually, with a separation of$3.2 \pm 0.3\ $AU and conclude that these masses are significantly higher ($30\%$) than what is predicted by theoretical stellar evolutionary models. The biggest uncertainty remains the distance to the system, here adopted as$20.1 \pm 2.0$pc based on trigonometric parallax, whose ambiguity has a major impact on the result. With the new observational data we are able to conclude that the orbital period of the BC pair is$8.41^{+0.04}_{-0.02}\ $years.Comment: 9 pages, 7 figures, accepted for publication in Astronomy & Astrophysic

Spectral characterization of newly detected young substellar binaries with SINFONI

We observe 14 young low-mass substellar objects in young moving groups using the SINFONI IFS with LGS-AO to detect and characterize 3 candidate binary systems. Together with the adopted young moving group ages we employ isochrones from substellar evolutionary models to estimate individual masses for the binaries. We find 2MASS J15104786-2818174 to be part of the $\approx 30 - 50$ Myr Argus moving group and composed of a $34 - 48\,M_{\rm Jup}$ primary brown dwarf with spectral type M$9\gamma$ and a fainter $15 - 22\, M_{\rm Jup}$ companion, separated by $\approx 100$ mas. 2MASS J22025794-5605087 is identified as an almost equal-mass binary in the AB Dor moving group, with a projected separation of $\approx 60$ mas. Both components share spectral type M$9\gamma/\beta$, which with the adopted age of $120 - 200$ Myr yields individual masses between $50 - 68\,M_{\rm Jup}$. The observations of 2MASS J15474719-2423493 are of lesser quality and we obtain no spectral characterization for the target, but resolve two components separated by $\approx 170$ mas which with the predicted young field age of $30 - 50$ Myr yields individual masses below $20\,M_{\rm Jup}$. Out of the 3 candidate binary systems, 2MASS J22025794-5605087 has unambiguous spectroscopic signs of being a bona-fide binary, while the other two will require second-epoch confirmation. The small projected separations between the binary components corresponds to physical separations of $\approx 4 - 7$ AU, allowing for astrometric monitoring of just a few years in order to generate constrained orbital fits and dynamical masses for the systems. In combination with their young ages, these binaries will prove to be excellent benchmarks for calibrating substellar evolutionary models down to a very low-mass regime.Comment: 17 pages, 14 figure

Modelling and experimental verification of more efficient power harvesting by coupled piezoelectric cantilevers

A new piezoelectric energy harvester design is proposed in order to achieve a wider bandwidth without compromising energy conversion efficiency. By coupling two cantilevers where the tip of the bottom one is attached to the base of the upper one, the simulated harvester will have a wider bandwidth and higher power output compared with two simulated single tuned single cantilevers. This is a compact design, using only half the area compared to two parallel single cantilevers at the price of a small increase in height. The measured coupled harvester has approximately 1.7 times higher energy output than the combination of two measured tuned single cantilevers achieved by a coupling with less mechanical damping. With an improved coupling the power output is increased to 2.3 times higher than two single tuned cantilevers

Islet Transplantation to the Anterior Chamber of the Eye—A Future Treatment Option for Insulin-Deficient Type-2 Diabetics? A Case Report from a Nonhuman Type-2 Diabetic Primate

10.1177/0963689720913256Cell Transplantation2

Wide-field mosaics of the corneal subbasal nerve plexus in Parkinson’s disease using in vivo confocal microscopy

In vivo confocal microscopy (IVCM) is a non-invasive imaging technique facilitating real-time acquisition of images from the live cornea and its layers with high resolution (1-2 mu m) and high magnification (600 to 800-fold). IVCM is extensively used to examine the cornea at a cellular level, including the subbasal nerve plexus (SBNP). IVCM of the cornea has thus gained intense interest for probing ophthalmic and systemic diseases affecting peripheral nerves. One of the main drawbacks, however, is the small field of view of IVCM, preventing an overview of SBNP architecture and necessitating subjective image sampling of small areas of the SBNP for analysis. Here, we provide a high-quality dataset of the corneal SBNP reconstructed by automated mosaicking, with an average mosaic image size corresponding to 48 individual IVCM fields of view. The mosaic dataset represents a group of 42 individuals with Parkinsons disease (PD) with and without concurrent restless leg syndrome. Additionally, mosaics from a control group (n = 13) without PD are also provided, along with clinical data for all included participants.Funding Agencies|Hofgrens fond, NEURO Sweden; Deutsche Forschungsgemeinschaft (DFG, German Research Foundation)German Research Foundation (DFG) [273371152]</p

Energieeffizientes Fahren 2014 (EFA2014) - 2. Projektphase Erhöhung der Reichweite von Elektrofahrzeugen: Abschlussbericht

In AP 1.4 wurde ein Verfahren zur Schaltzeitprognose verkehrsabhängiger Lichtsignalanlagen entwickelt, welches auf eine Vielzahl weiterer Lichtsignalanlagen anwendbar ist. Weiterhin wurden (AP.1.4.5) im Bereich der spurgenauen Ortung, die auf Basis von GPS ermittelten Positionen durch Fusion mit anderen Sensordaten, wie der axialen Beschleunigungen und den Drehraten um die Fahrzeughochachse sowie der Einbeziehung einer digitalen Karte (Digital Enhanced Map), diese hinsichtlich einer Spurdetektion weiterhin verbessert. Im Bereich der Datenübertragung (LSA-Fzg.) konnte die erste Teilstrecke von der Verkehrsmanagementzentrale zum Serviceprovider im Labor untersucht werden. In AP 2.1 wurde eine auf der optimalen Steuerung basierte Methode zum Energiemanagement von seriellen Hybriden entwickelt. Die optimale Ansteuerung von Motor-Start-Stopp, Gangwahl und Momentenaufteilung wird modellprädiktiv unter Beachtung des Kraftstoffverbrauchs und der Schademissionen berechnet. Nach Anpassung auf praktische Randbedingungen, lässt sich diese Methode in zukünftigen Hybridfahrzeugen als optimales Energiemanagement nutzen. Die in AP 3.1 entwickelte Softwareumgebung zur gekoppelten Fahrzeug und Verkehrssimulation wurde an Beispielszenarien getestet. Für ein Modell der Versuchsstrecke wurde umfangreiche Analysen des Ampelassistenzfunktion in komplexen Verkehrsszenarien durchgeführt. Für eine Variation verschiedener Parameter, wie Wirkreichweite, Verkehrsstärke, usw. konnten Aussagen über das Potential getroffen werden. In Zusammenarbeit mit AP 3.3 wurde ein Ampelassistenzsystem und die Ansteuerung des Active-Force-Feedback Pedals im Demonstrator implementiert. In AP 3.3 wurde ein Konzept zur Darstellung von LSA-Daten im Fahrzeug erarbeitet. Dieses wurde in einem Versuchsträger umgesetzt. Dazu wurde der Versuchsträger hardwareseitig ertüchtigt, und für die Untersuchung verschiedener Varianten der Darstellung eingesetzt.:I. Versionsübersicht 4 II. Kurze Darstellung 5 1. Aufgabenstellung 5 2. Voraussetzungen 6 3. Planung und Ablauf des Vorhabens 7 4. Wissenschaftlicher und technischer Stand 8 5. Bekannte Konstruktionen, Verfahren und Schutzrechte 9 6. verwendete Fachliteratur und Informations- und Dokumentationsdienste 9 7. Zusammenarbeit mit anderen Stellen 10 III. Eingehende Darstellung 11 1. Arbeitsinhalte und erzielte Ergebnisse 11 AP 1.4: Datenmanagement 11 AP 2.1: Range-Extender-Betriebsstrategien 40 AP 3.1: Fahrstrategie 63 AP 3.3: Mensch-Maschine-Interface 73 2. Nutzen der Ergebnisse 81 3. Fortschritt bei anderen Stellen 82 4. Veröffentlichungen und studentische Arbeiten 83 Vorträge 83 Publikationen 83 Studentische Arbeiten 84 IV. Literaturverzeichnis 8

XPR1 mediates the pancreatic B-cell phosphate flush

Glucose-stimulated insulin secretion is the hallmark of the pancreatic β-cell, a critical player in the regulation of blood glucose concentration. In 1974, the remarkable observation was made that an efflux of intracellular inorganic phosphate (P ) accompanied the events of stimulated insulin secretion. The mechanism behind this "phosphate flush," its association with insulin secretion, and its regulation have since then remained a mystery. We recapitulated the phosphate flush in the MIN6m9 β-cell line and pseudoislets. We demonstrated that knockdown of XPR1, a phosphate transporter present in MIN6m9 cells and pancreatic islets, prevented this flush. Concomitantly, XPR1 silencing led to intracellular P accumulation and a potential impact on Ca signaling. XPR1 knockdown slightly blunted first-phase glucose-stimulated insulin secretion in MIN6m9 cells, but had no significant impact on pseudoislet secretion. In keeping with other cell types, basal P efflux was stimulated by inositol pyrophosphates, and basal intracellular P accumulated following knockdown of inositol hexakisphosphate kinases. However, the glucose-driven phosphate flush occurred despite inositol pyrophosphate depletion. Finally, while it is unlikely that XPR1 directly affects exocytosis, it may protect Ca signaling. Thus, we have revealed XPR1 as the missing mediator of the phosphate flush, shedding light on a 45-year-old mystery