Stabilized high-power laser system for the gravitational wave detector advanced LIGO

An ultra-stable, high-power cw Nd:YAG laser system, developed for the ground-based gravitational wave detector Advanced LIGO (Laser Interferometer Gravitational-Wave Observatory), was comprehensively characterized. Laser power, frequency, beam pointing and beam quality were simultaneously stabilized using different active and passive schemes. The output beam, the performance of the stabilization, and the cross-coupling between different stabilization feedback control loops were characterized and found to fulfill most design requirements. The employed stabilization schemes and the achieved performance are of relevance to many high-precision optical experiments

Cryptotomography: reconstructing 3D Fourier intensities from randomly oriented single-shot diffraction patterns

We reconstructed the 3D Fourier intensity distribution of mono-disperse prolate nano-particles using single-shot 2D coherent diffraction patterns collected at DESY's FLASH facility when a bright, coherent, ultrafast X-ray pulse intercepted individual particles of random, unmeasured orientations. This first experimental demonstration of cryptotomography extended the Expansion-Maximization-Compression (EMC) framework to accommodate unmeasured fluctuations in photon fluence and loss of data due to saturation or background scatter. This work is an important step towards realizing single-shot diffraction imaging of single biomolecules.Comment: 4 pages, 4 figure

Stable Hydrogen Isotope Analysis of Bat Hair as Evidence for Seasonal Molt and Long-Distance Migration

Although hoary bats (Lasiurus cinereus) are presumed to be migratory and capable of long-distance dispersal, traditional marking techniques have failed to provide direct evidence of migratory movements by individuals. We measured the stable hydrogen isotope ratios of bat hair (∂Dh) and determined how these values relate to stable hydrogen isotope ratios of precipitation (∂Dp). Our results indicate that the major assumptions of stable isotope migration studies hold true for hoary bats and that the methodology provides a viable means of determining their migratory movements. We present evidence that a single annual molt occurs in L. cinereus prior to migration and that there is a strong relationship between ∂Dh and ∂Dp during the molt period. This presumably reflects the incorporation of local ∂Dp into newly grown hair. Furthermore, we present evidence that individual hoary bats are capable of traveling distances in excess of 2,000 km and that hair is grown at a wide range of latitudes and elevations. Stable hydrogen isotope analysis offers a promising new tool for the study of bat migration

Stable Hydrogen Isotope Analysis of Bat Hair as Evidence for Seasonal Molt and Long-Distance Migration

Although hoary bats (Lasiurus cinereus) are presumed to be migratory and capable of long-distance dispersal, traditional marking techniques have failed to provide direct evidence of migratory movements by individuals. We measured the stable hydrogen isotope ratios of bat hair (∂Dh) and determined how these values relate to stable hydrogen isotope ratios of precipitation (∂Dp). Our results indicate that the major assumptions of stable isotope migration studies hold true for hoary bats and that the methodology provides a viable means of determining their migratory movements. We present evidence that a single annual molt occurs in L. cinereus prior to migration and that there is a strong relationship between ∂Dh and ∂Dp during the molt period. This presumably reflects the incorporation of local ∂Dp into newly grown hair. Furthermore, we present evidence that individual hoary bats are capable of traveling distances in excess of 2,000 km and that hair is grown at a wide range of latitudes and elevations. Stable hydrogen isotope analysis offers a promising new tool for the study of bat migration

Dual-mode of insulin action controls GLUT4 vesicle exocytosis

Insulin releases an intracellular brake and promotes fusion pore expansion to translocate GLUT4 vesicles, and switches vesicle trafficking between distinct exocytic circuits

GEO 600 and the GEO-HF upgrade program: successes and challenges

The German-British laser-interferometric gravitational wave detector GEO 600 is in its 14th year of operation since its first lock in 2001. After GEO 600 participated in science runs with other first-generation detectors, a program known as GEO-HF began in 2009. The goal was to improve the detector sensitivity at high frequencies, around 1 kHz and above, with technologically advanced yet minimally invasive upgrades. Simultaneously, the detector would record science quality data in between commissioning activities. As of early 2014, all of the planned upgrades have been carried out and sensitivity improvements of up to a factor of four at the high-frequency end of the observation band have been achieved. Besides science data collection, an experimental program is ongoing with the goal to further improve the sensitivity and evaluate future detector technologies. We summarize the results of the GEO-HF program to date and discuss its successes and challenges

First recorded introduction of the milliped order Stemmiulida (Eugnatha: Nematophora): Potential establishment in Florida, USA, and new records from Mexico; northward range extension into southern Tamaulipas

Based on two “uni-ocellate” females, the world’s first introductions of the milliped order Stemmiulida are recorded from Florida, United States (US). One individual was collected in 1976 in Gainesville, Alachua County (Co.)., in northcentral peninsular Florida, and the other was taken in 1991 some 408 km (255 mi) to the south-southeast in Pompano Beach, Broward Co. The absence of further individuals and additional samples suggests that the introductions did not result in viable populations, and stemmiulidans are not presently established in the state; the Gainesville site was reinvestigated in 2012 without finding additional specimens. New records from Mexico include the first from Chiapas, Oaxaca, Tabasco, Yucatan, San Luis Potosí, and Tamaulipas states, with the northernmost ordinal locality now becoming Rancho del Cielo, northwest of Gómez Farias, in the last. A northward range expansion of about 460 km (288 mi) from the previous limit, Xalapa, Veracruz, the site lies a mere 40 km (25 mi) south of the Tropic of Cancer and only some 320 km (200 mi) south of the Rio Grande and the US border at McAllen, Hidalgo Co., Texas. Indigenous Stemmiulida are not expected in the forested Rio Grande Valley of southernmost Texas, but their occurrence in the adjoining Mexican state renders such a discovery more plausible than before

The conservation status of the world’s freshwater molluscs

With the biodiversity crisis continuing unchecked, we need to establish levels and drivers of extinction risk, and reassessments over time, to effectively allocate conservation resources and track progress towards global conservation targets. Given that threat appears particularly high in freshwaters, we assessed the extinction risk of 1428 randomly selected freshwater molluscs using the IUCN Red List Categories and Criteria, as part of the Sampled Red List Index project. We show that close to one-third of species in our sample are estimated to be threatened with extinction, with highest levels of threat in the Nearctic, Palearctic and Australasia and among gastropods. Threat levels were higher in lotic than lentic systems. Pollution (chemical and physical) and the modification of natural systems (e.g. through damming and water abstraction) were the most frequently reported threats to freshwater molluscs, with some regional variation. Given that we found little spatial congruence between species richness patterns of freshwater molluscs and other freshwater taxa, apart from crayfish, new additional conservation priority areas emerged from our study. We discuss the implications of our findings for freshwater mollusc conservation, the adequacy of a sampled approach and important next steps to estimate trends in freshwater mollusc extinction risk over time

Reaction of Cinnamoyl Chloride with a Dialkylcadmium Reagent

It was demonstrated that a dialkylcadmium reagent would successfully react with the unsaturated acid chloride, cinnamoyl chloride, under both ordinary conditions and at 0 ° in the presence of ferric chloride to give the alkyl styryl ketone in yields of 54% and 46% respectively. The nbutyl styryl ketone obtained in the reaction displayed infrared absorbtion at 5.92 μ (C=O) and at 6.04 μ (C=C). The dipole moment was found to be 3.16 D in benzene solution at 25°