Efficient β-cell regeneration by a combination of neogenesis and replication following β-cell ablation and reversal of pancreatic duct ligation.

Achieving efficient β-cell regeneration is a major goal of diabetes research. Previously, we found that a combination of β-cell ablation and pancreatic duct ligation led to β-cell regeneration by direct conversion from α-cells. Here, we studied the effect of surgical reversal of the duct ligation, finding that there was a wave of β-cell replication following reversal. The combination of β-cell neogenesis prior to reversal of the duct ligation and β-cell replication following reversal resulted in efficient β-cell regeneration and eventual recovery of function. This provides an important proof of principle that efficient β-cell regeneration is possible, even from a starting point of profound β-cell ablation. This has important implications for efforts to promote β-cell regeneration

Comparison of outcomes in patients undergoing defibrillation threshold testing at the time of implantable cardioverter-defibrillator implantation versus no defibrillation threshold testing

Background: Inability to perform defibrillation threshold (DFT) testing during implantable cardioverter defibrillator (ICD) implantation due to co-morbidities may influence long-term survival. Methods: Retrospective review at The University of Michigan (1999-2004) identified 55 patients undergoing ICD implantation without DFT testing (“No-DFT group”). A randomly selected sample of patients (n = 57) undergoing standard DFT testing (“DFT group”) was compared in terms of appropriate shocks, clinical shock efficacy and all-cause mortality. Results: DFT testing was withheld due to hypotension, atrial fibrillation with inability to exclude left atrial thrombus, left ventricular thrombus, CHF and/or ischemia. The No-DFT group had a similar appropriate shock rate, but lower total survival (69.1% vs. 91.2%, p = 0.004) than the DFT group. The No-DFT group had a higher incidence of ventricular fibrillation (VF) episodes (9.1% vs. 3.1%, p = 0.037), and deaths attributable to VF (3 of 17 deaths vs. 0 of 5 deaths) compared to the DFT group. Multivariate analysis found a trend toward increased risk of death in the No-DFT group (HR 3.18, 95% CI 0.82-12.41, p = 0.095) after adjusting for baseline differences in gender distribution, NYHA class and prior CABG. Conclusions: In summary, overall mortality was higher in the No-DFT group. More deaths attributable to VF occurred in the No-DFT group. Thus, DFT testing should therefore remain the standard of care. Nevertheless, ICD therapy should not be withheld in patients who meet appropriate implant criteria simply on the basis of clinical scenarios that preclude routine DFT testing. (Cardiol J 2007; 14: 463-469

Feasibility of Ultraviolet Light Emitting Diodes as an Alternative Light Source for Photocatalysis

The objective of this study was to determine whether ultraviolet light emitting diodes (UV-LEDs) could serve as an alternative photon source efficiently for heterogeneous photocatalytic oxidation (PCO). An LED module consisting of 12 high-power UV-A LEDs was designed to be interchangeable with a UV-A fluorescent black light blue (BLB) lamp in a Silica-Titania Composite (STC) packed bed annular reactor. Lighting and thermal properties were characterized to assess the uniformity and total irradiant output. A forward current of (I(sub F)) 100 mA delivered an average irradiance of 4.0 m W cm(exp -2), which is equivalent to the maximum output of the BLB, but the irradiance of the LED module was less uniform than that of the BLB. The LED- and BLB-reactors were tested for the oxidization of 50 ppmv ethanol in a continuous flow-through mode with 0.94 sec space time. At the same irradiance, the UV-A LED reactor resulted in a lower PCO rate constant than the UV-A BLB reactor (19.8 vs. 28.6 nM CO2 sec-I), and consequently lower ethanol removal (80% vs. 91%) and mineralization efficiency (28% vs. 44%). Ethanol mineralization increased in direct proportion to the irradiance at the catalyst surface. This result suggests that reduced ethanol mineralization in the LED- reactor could be traced to uneven irradiance over the photocatalyst, leaving a portion of the catalyst was under-irradiated. The potential of UV-A LEDs may be fully realized by optimizing the light distribution over the catalyst and utilizing their instantaneous "on" and "off' feature for periodic irradiation. Nevertheless, the current UV-A LED module had the same wall plug efficiency (WPE) of 13% as that of the UV-A BLB. These results demonstrated that UV-A LEDs are a viable photon source both in terms of WPE and PCO efficiency

Moyo Vol. VII N 1

Durica, Paul. Editor\u27s Letter . 4 Lemke, Angelica. Paxil, Effexor, and Prozac, Oh My! Is Depression Awareness Day Going Too Far? 5. Frey, Randall. Just Be: How to Make Money Without Really Doing Anything . 6. Purks, Robert. 007, Missing The Action. Dalton\u27s Bond Reconsidered . 7. Stine, Alison. Hatching A masterpiece: Jeffery Hatcher Talks of Writing, Melville, Woody Allen, and Denison . 8. Levine, Robert. Dial DU For Murder: Cinema Student Shuffles Off The Mortal Coil, and Finds it an Acquired Taste . 13. Almirall, Sarah. Dial DU For Murder: Cinema Student Shuffles Off The Mortal Coil, and Finds it an Acquired Taste, Photographs . 13. Werne, Kirsten. Back in the Day (Mom and Pop Alums Reflect on the Sixties Social Scene) . 18. Kohlbecker, Matthew. Between a Rock and a Hard Place (A Geological Excursion Into the Wilds of Canada) . 20. Lammont, Jean. Where\u27s Waldon? Comments on the Homestead . 21. Frey, Randall. Me Experimenting with Berry Beer . 25. Frey, Randall. Shoes for Mr. Jordan . 28. Porcheddu, Fred. My Late Adolescence . 30. Combe, Clayton. The Modern Guinea Pig . 31

Porównanie wyników leczenia u pacjentów poddawanych lub niepoddawanych ocenie progu defibrylacji w czasie wszczepienia kardiowertera-defibrylatora

Wstęp: Brak możliwości przeprowadzenia oceny progu defibrylacji (DFT) podczas implantacji kardiowertera-defibrylatora (ICD) ze względu na występowanie współistniejących chorób może wpływać na przeżywalność w obserwacji odległej. Metody: W retrospektywnym przeglądzie przeprowadzonym na University of Michigan (1999-2004) zidentyfikowano 55 pacjentów, u których przeprowadzono implantację ICD bez oceny DFT. Grupę tą porównano pod względem występowania uzasadnionych wyładowań, ich klinicznej skuteczności oraz całkowitej śmiertelności z losowo wybraną grupą osób (n = 57), u których przeprowadzono standardową ocenę DFT. Wyniki: Oceny DFT nie dokonywano z powodu niskiej wartości ciśnienia tętniczego, migotania przedsionków z niemożnością wykluczenia skrzepliny w lewym przedsionku, skrzepliny w lewej komorze, zastoinowej niewydolności serca i/lub niedokrwienia. W grupie bez oceny DFT liczba uzasadnionych wyładowań była podobna, natomiast łączne przeżycie mniejsze (69,1% vs. 91,2%; p = 0,004) niż w grupie poddawanej ocenie DFT. W grupie bez oceny DFT stwierdzono większą częstość incydentów migotania komór (VF; 9,1% vs. 3,1%; p = 0,037) i zgonów z powodu VF (3 spośród 17 zgonów vs. 0 spośród 5 zgonów) ni¿ w grupie poddawanej ocenie DFT. W analizie wielozmiennej wykazano trend w kierunku zwiększonego ryzyka zgonów w grupie bez oceny DFT [iloraz hazardu (HR) 3,18; 95% przedział ufności (CI) 0,82–12,41; p = 0,095] po uwzględnieniu początkowych różnic rozkładu płci, klasy czynnościowej według Nowojorskiego Towarzystwa Kardiologicznego (NYHA) oraz wcześniejszego pomostowania tętnic wieńcowych. Wnioski: Całkowita śmiertelność była większa w grupie bez oceny DFT, gdzie wystąpiło więcej zgonów, które można było przypisywać VF. Ocena DFT powinna więc pozostać standardem postępowania. Mimo to nie należy rezygnować z leczenia za pomocą ICD u pacjentów, którzy spełniają kryteria implantacji, jeżeli jedynym powodem tego miałoby być występowanie sytuacji klinicznych wykluczających ocenę DFT

The Milky Way's circular velocity curve between 4 and 14 kpc from APOGEE data

We measure the Milky Way's rotation curve over the Galactocentric range 4 kpc <~ R <~ 14 kpc from the first year of data from the Apache Point Observatory Galactic Evolution Experiment (APOGEE). We model the line-of-sight velocities of 3,365 stars in fourteen fields with b = 0 deg between 30 deg < l < 210 deg out to distances of 10 kpc using an axisymmetric kinematical model that includes a correction for the asymmetric drift of the warm tracer population (\sigma_R ~ 35 km/s). We determine the local value of the circular velocity to be V_c(R_0) = 218 +/- 6 km/s and find that the rotation curve is approximately flat with a local derivative between -3.0 km/s/kpc and 0.4 km/s/kpc. We also measure the Sun's position and velocity in the Galactocentric rest frame, finding the distance to the Galactic center to be 8 kpc < R_0 < 9 kpc, radial velocity V_{R,sun} = -10 +/- 1 km/s, and rotational velocity V_{\phi,sun} = 242^{+10}_{-3} km/s, in good agreement with local measurements of the Sun's radial velocity and with the observed proper motion of Sgr A*. We investigate various systematic uncertainties and find that these are limited to offsets at the percent level, ~2 km/s in V_c. Marginalizing over all the systematics that we consider, we find that V_c(R_0) 99% confidence. We find an offset between the Sun's rotational velocity and the local circular velocity of 26 +/- 3 km/s, which is larger than the locally-measured solar motion of 12 km/s. This larger offset reconciles our value for V_c with recent claims that V_c >~ 240 km/s. Combining our results with other data, we find that the Milky Way's dark-halo mass within the virial radius is ~8x10^{11} M_sun.Comment: submitted to Ap

LSST: from Science Drivers to Reference Design and Anticipated Data Products

(Abridged) We describe here the most ambitious survey currently planned in the optical, the Large Synoptic Survey Telescope (LSST). A vast array of science will be enabled by a single wide-deep-fast sky survey, and LSST will have unique survey capability in the faint time domain. The LSST design is driven by four main science themes: probing dark energy and dark matter, taking an inventory of the Solar System, exploring the transient optical sky, and mapping the Milky Way. LSST will be a wide-field ground-based system sited at Cerro Pach\'{o}n in northern Chile. The telescope will have an 8.4 m (6.5 m effective) primary mirror, a 9.6 deg$^2$ field of view, and a 3.2 Gigapixel camera. The standard observing sequence will consist of pairs of 15-second exposures in a given field, with two such visits in each pointing in a given night. With these repeats, the LSST system is capable of imaging about 10,000 square degrees of sky in a single filter in three nights. The typical 5$\sigma$ point-source depth in a single visit in $r$ will be $\sim 24.5$ (AB). The project is in the construction phase and will begin regular survey operations by 2022. The survey area will be contained within 30,000 deg$^2$ with $\delta<+34.5^\circ$, and will be imaged multiple times in six bands, $ugrizy$, covering the wavelength range 320--1050 nm. About 90\% of the observing time will be devoted to a deep-wide-fast survey mode which will uniformly observe a 18,000 deg$^2$ region about 800 times (summed over all six bands) during the anticipated 10 years of operations, and yield a coadded map to $r\sim27.5$. The remaining 10\% of the observing time will be allocated to projects such as a Very Deep and Fast time domain survey. The goal is to make LSST data products, including a relational database of about 32 trillion observations of 40 billion objects, available to the public and scientists around the world.Comment: 57 pages, 32 color figures, version with high-resolution figures available from https://www.lsst.org/overvie