762 research outputs found
The Robber Flies (Diptera: Asilidae) of the Albany Pinebush
The Albany Pinebush, a pitch pine-scrub oak sand barrens, was examined for robber flies and the results compared to historical records found in the New York State Museum, Albany. Thirty-six species were recorded of which seventeen were new records. Two species, Cyrtopogon laphriformis and Promachus bastardii, last recorded in 1914 and 1931, respectively, were not located in the survey
Responsive glyco-poly(2-oxazoline)s: synthesis, cloud point tuning, and lectin binding
A new sugar-substituted 2-oxazoline monomer was prepared using the copper-catalyzed alkyne-azide cycloaddition (CuAAC) reaction. Its copolymerization with 2-ethyl-2-oxazoline as well as 2-(dec-9-enyl)-2-oxazoline, yielding well-defined copolymers with the possibility to tune the properties by thiol-ene "click" reactions, is described. Extensive solubility studies on the corresponding glycocopolymers demonstrated that the lower critical solution temperature behavior and pH-responsiveness of these copolymers can be adjusted in water and phosphate-buffered saline (PBS) depending on the choice of the thiol. By conjugation of 2,3,4,6-tetra-O-acetyl-1-thio-beta-D-glucopyranose and subsequent deprotection of the sugar moieties, the hydrophilicity of the copolymer could be increased significantly, allowing a cloud-point tuning in the physiological range. Furthermore, the binding capability of the glycosylated copoly(2-oxazoline) to concanavalin A was investigated
Absolute Energy Measurements with Superconducting Transition-Edge Sensors for Muonic X-ray Spectroscopy at 44 keV
Superconducting transition-edge sensor (TES) microcalorimeters have great
utility in x-ray applications owing to their high energy resolution, good
collecting efficiency and the feasibility of being multiplexed into large
arrays. In this work, we develop hard x-ray TESs to measure the absolute
energies of muonic-argon (-Ar) transition lines around 44 keV and 20 keV.
TESs with sidecar absorbers of different heat capacities were fabricated and
characterized for their energy resolution and calibration uncertainty. We
achieved ~ 1 eV absolute energy measurement accuracy at 44 keV, and < 12 eV
energy resolution at 17.5 keV
CFH, C3 and ARMS2 Are Significant Risk Loci for Susceptibility but Not for Disease Progression of Geographic Atrophy Due to AMD
Age-related macular degeneration (AMD) is a prevalent cause of blindness in Western societies. Variants in the genes encoding complement factor H (CFH), complement component 3 (C3) and age-related maculopathy susceptibility 2 (ARMS2) have repeatedly been shown to confer significant risks for AMD; however, their role in disease progression and thus their potential relevance for interventional therapeutic approaches remains unknown. Here, we analyzed association between variants in CFH, C3 and ARMS2 and disease progression of geographic atrophy (GA) due to AMD. A quantitative phenotype of disease progression was computed based on longitudinal observations by fundus autofluorescence imaging. In a subset of 99 cases with pure bilateral GA, variants in CFH (Y402H), C3 (R102G), and ARMS2 (A69S) are associated with disease (P = 1.6x10(-9), 3.2x10(-3), and P = 2.6x10(-12), respectively) when compared to 612 unrelated healthy control individuals. In cases, median progression rate of GA over a mean follow-up period of 3.0 years was 1.61 mm(2)/year with high concordance between fellow eyes. No association between the progression rate and any of the genetic risk variants at the three loci was observed (P>0.13). This study confirms that variants at CFH, C3, and ARMS2 confer significant risks for GA due to AMD. In contrast, our data indicate no association of these variants with disease progression which may have important implications for future treatment strategies. Other, as yet unknown susceptibilities may influence disease progression
A Tabletop X-Ray Tomography Instrument for Nanometer-Scale Imaging: Integration of a Scanning Electron Microscope with a Transition-Edge Sensor Spectrometer
X-ray nanotomography is a powerful tool for the characterization of nanoscale
materials and structures, but is difficult to implement due to competing
requirements on X-ray flux and spot size. Due to this constraint,
state-of-the-art nanotomography is predominantly performed at large synchrotron
facilities. Compact X-ray nanotomography tools operated in standard analysis
laboratories exist, but are limited by X-ray optics and destructive sample
preparation techniques. We present a laboratory-scale nanotomography instrument
that achieves nanoscale spatial resolution while changing the limitations of
conventional tomography tools. The instrument combines the electron beam of a
scanning electron microscope (SEM) with the precise, broadband X-ray detection
of a superconducting transition-edge sensor (TES) microcalorimeter. The
electron beam generates a highly focused X-ray spot in a metal target, while
the TES spectrometer isolates target photons with high signal-to-noise. This
combination of a focused X-ray spot, energy-resolved X-ray detection, and
unique system geometry enable nanoscale, element-specific X-ray imaging in a
compact footprint. The proof-of-concept for this approach to X-ray
nanotomography is demonstrated by imaging 160 nm features in three dimensions
in a Cu-SiO2 integrated circuit, and a path towards finer resolution and
enhanced imaging capabilities is discussed.Comment: The following article has been submitted to Physical Review Applie
Y-Chromosome Variation in Hominids: Intraspecific Variation Is Limited to the Polygamous Chimpanzee
The original publication is available at www.plosone.orgBackground: We have previously demonstrated that the Y-specific ampliconic fertility genes DAZ (deleted in azoospermia)
and CDY (chromodomain protein Y) varied with respect to copy number and position among chimpanzees (Pan troglodytes).
In comparison, seven Y-chromosomal lineages of the bonobo (Pan paniscus), the chimpanzee’s closest living relative,
showed no variation. We extend our earlier comparative investigation to include an analysis of the intraspecific variation of
these genes in gorillas (Gorilla gorilla) and orangutans (Pongo pygmaeus), and examine the resulting patterns in the light of
the species’ markedly different social and mating behaviors.
Methodology/Principal Findings: Fluorescence in situ hybridization analysis (FISH) of DAZ and CDY in 12 Y-chromosomal
lineages of western lowland gorilla (G. gorilla gorilla) and a single lineage of the eastern lowland gorilla (G. beringei graueri)
showed no variation among lineages. Similar findings were noted for the 10 Y-chromosomal lineages examined in the
Bornean orangutan (Pongo pygmaeus), and 11 Y-chromosomal lineages of the Sumatran orangutan (P. abelii). We validated
the contrasting DAZ and CDY patterns using quantitative real-time polymerase chain reaction (qPCR) in chimpanzee and
bonobo.
Conclusion/Significance: High intraspecific variation in copy number and position of the DAZ and CDY genes is seen only in
the chimpanzee. We hypothesize that this is best explained by sperm competition that results in the variant DAZ and CDY
haplotypes detected in this species. In contrast, bonobos, gorillas and orangutans—species that are not subject to sperm
competition—showed no intraspecific variation in DAZ and CDY suggesting that monoandry in gorillas, and preferential
female mate choice in bonobos and orangutans, probably permitted the fixation of a single Y variant in each taxon. These
data support the notion that the evolutionary history of a primate Y chromosome is not simply encrypted in its DNA
sequences, but is also shaped by the social and behavioral circumstances under which the specific species has evolved.Funded by the Deutsche Forschungsgemeinschaft (SCHE 214/8)Publisher's versio
Affective Reactions Influence Investment Decisions: Evidence from a Laboratory Experiment With Taxation
Why small-quantity lipid-based nutrient supplements should be integrated into comprehensive strategies to prevent child undernutrition in nutritionally vulnerable populations : response to Gupta et al.’s commentary
We write in response to the commentary by Gupta et al. (2023) on small-quantity lipid-based nutrient supplements (SQ-LNS) for infants and young children 6 to 24 months of age, which was prompted by the recent brief guidance note from UNICEF (2023) explaining when, why and how SQ-LNS are being prioritized as part of their package of preventive actions to combat early childhood malnutrition. The UNICEF document was disseminated shortly after publication of a correspondence in Nature Food (Aguayo et al. 2023), authored by nutrition leaders from several organizations, that summarized the evidence on the benefits of SQ-LNS and called for this intervention to be scaled up and integrated into programs for populations in which child undernutrition is prevalent and dietary quality is very poor. We agree with Gupta et al. that child malnutrition is the result of many factors and there is no single “quick fix” or “magic bullet”. In fact, the above-cited documents state clearly and frequently that provision of SQ-LNS is not a stand-alone intervention and must be integrated into comprehensive strategies to improve infant and young child feeding (IYCF), including the promotion of dietary diversity, as well as other actions needed to prevent malnutrition. SQ-LNS are intended for vulnerable populations who lack access to an affordable, nutritionally adequate complementary feeding diet and have high rates of stunting, wasting and mortality. In such populations, we agree with Gupta et al. that IYCF messages alone are not enough. This is precisely why SQ-LNS were originally developed
Measurement of the cosmic ray spectrum above eV using inclined events detected with the Pierre Auger Observatory
A measurement of the cosmic-ray spectrum for energies exceeding
eV is presented, which is based on the analysis of showers
with zenith angles greater than detected with the Pierre Auger
Observatory between 1 January 2004 and 31 December 2013. The measured spectrum
confirms a flux suppression at the highest energies. Above
eV, the "ankle", the flux can be described by a power law with
index followed by
a smooth suppression region. For the energy () at which the
spectral flux has fallen to one-half of its extrapolated value in the absence
of suppression, we find
eV.Comment: Replaced with published version. Added journal reference and DO
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