586 research outputs found
Spectrally tunable magnetic nanoparticles designed for distribution/recollection applications
The comprehensive goal of this research is the synthesis and characterization of nanomaterials that are spectrally tunable in terms of their electromagnetic signal, are robust, magnetic (allowing their piloted movement), and have the potential to be functionalized for the detection of CBRNE threats. Various chemical methods were utilized for synthesis of magnetic (iron) and luminescent rare earth (RE) components, and their mixtures. Effects of integrating an iron core into RE luminescent lattices (excited by UV, emit in the VIS) were investigated. The determination of the optimum balances between magnetic and luminescent components such that the magnetism was maximized while maintaining acceptable fluorescence integrity will be discussed. The emphasis of this work is focused on developing a distributed sensor suitable for use in the terrestrial environment. The robust properties of using a RE luminescent shell would allow the particles to be resistant to photobleaching. Additionally the chemical stability of the RE shell would allow operation in a variety of pH conditions. The magnetic core will ultimately allow the distributed particles to be recollected
Detection of a Pair Density Wave State in UTe
Although UTe is a very promising candidate material to embody bulk
topological superconductivity, its superconductive order-parameter
remains unknown. Many diverse forms for
are physically possible because, in uranium-based heavy
fermion materials, strongly hybridized flat bands of composite fermions
generate highly complex interactions. Moreover, in such materials intertwined
density waves of spin (SDW), charge (CDW) and pairs (PDW) may interpose, with
the latter state exhibiting spatially modulating superconductive
order-parameter , electron pair density and pairing
energy-gap. Hence, the newly discovered CDW state in UTe motivates the
exciting prospect that a PDW state may exist in this material. To search for a
PDW in UTe, we visualize the pairing energy-gap with -scale
energy-resolution made possible by superconductive STM tips at subkelvin
temperatures. We detect three PDWs, each with peak-peak gap modulations circa
10 and at incommensurate wavevectors that are
indistinguishable from the wavevectors of the prevenient
CDW. Concurrent visualization of the UTe superconductive PDWs and the
non-superconductive CDWs reveals that every :
pair is registered to each other spatially, but with a relative phase
. From these observations, and given UTe as a
spin-triplet superconductor, the PDW state detected here should be a
spin-triplet pair density wave. While such states do exist in superfluid
He, for superconductors they are unprecedented.Comment: 37 pages, 13 figure
Clinical translation of a click-labeled 18F-octreotate radioligand for imaging neuroendocrine tumors
© 2016 by the Society of Nuclear Medicine and Molecular Imaging, Inc. We conducted the first-in-human study of 18F-fluoroethyl triazole [Tyr3] octreotate (18F-FET-βAG-TOCA) in patients with neuroendocrine tumors (NETs) to evaluate biodistribution, dosimetry, and safety. Despite advances in clinical imaging, detection and quantification of NET activity remains a challenge, with no universally accepted imaging standard. Methods: Nine patients were enrolled. Eight patients had sporadic NETs, and 1 had multiple endocrine neoplasia type 1 syndrome. Patients received 137-163 MBq (mean ± SD, 155.7 ± 8 MBq) of 18F-FET-βAG-TOCA. Safety data were obtained during and 24 h after radioligand administration. Patients underwent detailed wholebody PET/CT multibed scanning over 4 h with sampling of venous bloods for radioactivity and radioactive metabolite quantification. Regions of interest were defined to derive individual and mean organ residence times; effective dose was calculated with OLINDA 1.1. Results: All patients tolerated 18F-FET-βAG-TOCA with no adverse events. Over 60% parent radioligand was present in plasma at 60 min. High tumor (primary and metastases)-to-background contrast images were observed. Physiologic distribution was seen in the pituitary, salivary glands, thyroid, and spleen, with low background distribution in the liver, an organ in which metastases commonly occur. The organs receiving highest absorbed dose were the gallbladder, spleen, stomach, liver, kidneys, and bladder. The calculated effective dose over all subjects (mean ± SD) was 0.029 ± 0.004 mSv/MBq. Conclusion: The favorable safety, imaging, and dosimetric profile makes 18F-FET-βAGTOCA a promising candidate radioligand for staging and management of NETs. Clinical studies in an expanded cohort are ongoing to clinically qualify this agent
Evaluation of SmartStax and SmartStax PRO Maize against Western Corn Rootworm and Northern Corn Rootworm: Efficacy and Resistance Management
Background: Cases of western corn rootworm (WCR) field-evolved resistance to Cry3Bb1 and other corn rootworm (CRW) control traits have been reported. Pyramid products expressing multiple CRW traits can delay resistance compared to single trait products. We used field studies to assess the pyramid CRW corn products, SmartStax (expressing Cry3Bb1 and Cry34Ab1/Cry35Ab1) and SmartStax PRO (expressing Cry3Bb1, Cry34Ab1/Cry35Ab1 and DvSnf7), at locations with high WCR densities and possible Cry3Bb1 resistance, and to assess the reduction in adult emergence attributable to DvSnf7 and other traits. Insect resistance models were used to assess durability of SmartStax and SmartStax PRO to WCR resistance.
Results: SmartStax significantly reduced root injury compared to non-CRW-trait controls at all but one location with measurable WCR pressure, while SmartStax PRO significantly reduced root injury at all locations, despite evidence of Cry3Bb1 resistance at some locations. The advantage of SmartStax PRO over SmartStax in reducing root damage was positively correlated with root damage on non-CRW-trait controls. DvSnf7 was estimated to reduce WCR emergence by approximately 80–95%, which modeling indicated will improve durability of Cry3Bb1 and Cry34Ab1/Cry35Ab1 compared to SmartStax.
Conclusion: The addition of DvSnf7 in SmartStax PRO can reduce root damage under high WCR densities and prolong Cry3Bb1 and Cry34Ab1/Cry35Ab1 durability
The Circadian Clock Protein BMAL1 Acts as a Metabolic Sensor In Macrophages to Control the Production of Pro IL-1β
The transcription factor BMAL1 is a clock protein that generates daily or circadian rhythms in physiological functions including the inflammatory response of macrophages. Intracellular metabolic pathways direct the macrophage inflammatory response, however whether the clock is impacting intracellular metabolism to direct this response is unclear. Specific metabolic reprogramming of macrophages controls the production of the potent pro-inflammatory cytokine IL-1β. We now describe that the macrophage molecular clock, through Bmal1, regulates the uptake of glucose, its flux through glycolysis and the Krebs cycle, including the production of the metabolite succinate to drive Il-1β production. We further demonstrate that BMAL1 modulates the level and localisation of the glycolytic enzyme PKM2, which in turn activates STAT3 to further drive Il-1β mRNA expression. Overall, this work demonstrates that BMAL1 is a key metabolic sensor in macrophages, and its deficiency leads to a metabolic shift of enhanced glycolysis and mitochondrial respiration, leading to a heightened pro-inflammatory state. These data provide insight into the control of macrophage driven inflammation by the molecular clock, and the potential for time-based therapeutics against a range of chronic inflammatory diseases
Luminous Red Galaxy Clustering at z~0.7 - First Results using AAOmega
We report on the AAT-AAOmega LRG Pilot observing run to establish the
feasibility of a large spectroscopic survey using the new AAOmega instrument.
We have selected Luminous Red Galaxies (LRGs) using single epoch SDSS
riz-photometry to i<20.5 and z<20.2. We have observed in 3 fields including the
COSMOS field and the COMBO-17 S11 field, obtaining a sample of ~600 redshift
z>=0.5 LRGs. Exposure times varied from 1 - 4 hours to determine the minimum
exposure for AAOmega to make an essentially complete LRG redshift survey in
average conditions. We show that LRG redshifts to i<20.5 can measured in
approximately 1.5hr exposures and present comparisons with 2SLAQ and COMBO-17
(photo-)redshifts. Crucially, the riz selection coupled with the 3-4 times
improved AAOmega throughput is shown to extend the LRG mean redshift from
z=0.55 for 2SLAQ to z=0.681+/- 0.005 for riz-selected LRGs. This extended range
is vital for maximising the S/N for the detection of the baryon acoustic
oscillations (BAOs). Furthermore, we show that the amplitude of LRG clustering
is s_0 = 9.9+/-0.7 h^-1 Mpc, as high as that seen in the 2SLAQ LRG Survey.
Consistent results for the real-space amplitude are found from projected and
semi-projected correlation functions. This high clustering amplitude is
consistent with a long-lived population whose bias evolves as predicted by a
simple ``high-peaks'' model. We conclude that a redshift survey of 360 000 LRGs
over 3000deg^2, with an effective volume some 4 times bigger than previously
used to detect BAO with LRGs, is possible with AAOmega in 170 nights.Comment: 12 pages, 7 figures, 8 tables, minor changes, matches published
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A review of wind turbine main-bearings: design, operation, modelling, damage mechanisms and fault detection
This paper presents a review of existing theory and practice relating to main-bearings for wind turbines. The mainbearing performs the critical role of supporting the turbine rotor, with replacements typically requiring its complete removal. The operational conditions and loading for wind turbine main-bearings deviate significantly from those of more conventional power plants and other bearings present in the wind turbine power-train, i.e. those in the gearbox and generator. This work seeks to thoroughly document current main-bearing theory in order to allow for appraisal of existing design and analysis practices, while also seeking to form a solid foundation for future research in this area. The most common main-bearing setups are presented along with standards for bearing selection and rating. Typical loads generated by a wind turbine rotor, and subsequently reacted at the main-bearing, are discussed. This is followed by the related tribological theories of lubrication, wear and associated failure mechanisms. Finally, existing techniques for bearing modeling, fault diagnosis and prognosis relevant to the main-bearing are presented
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