97 research outputs found
Sellafield Thermal Treatment Trials Using Advanced Joule Heated Ceramic Melter Technology -WM-10110
ABSTRACT The viability of thermal treatment using vitrification to immobilize two types of Sellafield intermediate level wastes (ILW) has been successfully demonstrated in proof-of-concept trials. The testing employed a type of Joule Heated Ceramic Melter (JHCM) technology that incorporates active mixing of the melt pool. Melt pool mixing improves heat and mass transport, increases waste processing rates, thereby reducing systems size and/or operating duration, and therefore overall treatment costs. Simulants for two Sellafield ILW streams-a Magnox sludge and a sand/clinoptilolite ion exchange waste slurry-were developed for testing in this work. Glass formulations were developed and tested for each of the two ILW streams. Acceptable glass formulations that met all processability and product quality constraints were selected for testing on a small-scale continuously-fed vitrification system. Two tests of nominally 50-hour duration were completed. Data were collected to characterize operating conditions, processing rates, and glass and off-gas compositions for mass balance. Key performance objectives included minimum nonactive additives; maximum volume reduction for the wastes; maximum retention of radionuclide and chemotoxic elements; minimal secondary wastes that require other processing; maximum passivation and stabilization of wastes; and meeting product compliance requirements. Test results demonstrate that vitrification using JHCM technology is well suited to immobilize the two Sellafield waste streams tested. The required system size and operating duration are well within the realm of prior experience of this technology. The technology offers the potential to significantly reduce lifecycle cost because the high volume reductions minimize the volume of treated wastes to be disposed, while the glass waste form offers superior waste form performance compared to almost all alternatives
Bipartite binding and partial inhibition links DEPTOR and mTOR in a mutually antagonistic embrace.
The mTORC1 kinase complex regulates cell growth, proliferation, and survival. Because mis-regulation of DEPTOR, an endogenous mTORC1 inhibitor, is associated with some cancers, we reconstituted mTORC1 with DEPTOR to understand its function. We find that DEPTOR is a unique partial mTORC1 inhibitor that may have evolved to preserve feedback inhibition of PI3K. Counterintuitively, mTORC1 activated by RHEB or oncogenic mutation is much more potently inhibited by DEPTOR. Although DEPTOR partially inhibits mTORC1, mTORC1 prevents this inhibition by phosphorylating DEPTOR, a mutual antagonism that requires no exogenous factors. Structural analyses of the mTORC1/DEPTOR complex showed DEPTOR's PDZ domain interacting with the mTOR FAT region, and the unstructured linker preceding the PDZ binding to the mTOR FRB domain. The linker and PDZ form the minimal inhibitory unit, but the N-terminal tandem DEP domains also significantly contribute to inhibition
Capturing the Surface Texture and Shape of Pollen: A Comparison of Microscopy Techniques
Research on the comparative morphology of pollen grains depends crucially on the application of appropriate microscopy techniques. Information on the performance of microscopy techniques can be used to inform that choice. We compared the ability of several microscopy techniques to provide information on the shape and surface texture of three pollen types with differing morphologies. These techniques are: widefield, apotome, confocal and two-photon microscopy (reflected light techniques), and brightfield and differential interference contrast microscopy (DIC) (transmitted light techniques). We also provide a first view of pollen using super-resolution microscopy. The three pollen types used to contrast the performance of each technique are: Croton hirtus (Euphorbiaceae), Mabea occidentalis (Euphorbiaceae) and Agropyron repens (Poaceae). No single microscopy technique provided an adequate picture of both the shape and surface texture of any of the three pollen types investigated here. The wavelength of incident light, photon-collection ability of the optical technique, signal-to-noise ratio, and the thickness and light absorption characteristics of the exine profoundly affect the recovery of morphological information by a given optical microscopy technique. Reflected light techniques, particularly confocal and two-photon microscopy, best capture pollen shape but provide limited information on very fine surface texture. In contrast, transmitted light techniques, particularly differential interference contrast microscopy, can resolve very fine surface texture but provide limited information on shape. Texture comprising sculptural elements that are spaced near the diffraction limit of light (∼250 nm; NDL) presents an acute challenge to optical microscopy. Super-resolution structured illumination microscopy provides data on the NDL texture of A. repens that is more comparable to textural data from scanning electron microscopy than any other optical microscopy technique investigated here. Maximizing the recovery of morphological information from pollen grains should lead to more robust classifications, and an increase in the taxonomic precision with which ancient vegetation can be reconstructed
Delineating ADHD and bipolar disorder: A comparison of clinical profiles in adult women
OBJECTIVE: Overlapping symptoms can make the diagnostic differentiation of attention-deficit/hyperactivity disorder (ADHD) and bipolar disorder (BD) challenging in adults using current clinical assessments. This study sought to determine if current clinical measures delineate ADHD from BD in adults, comparing relative levels of ADHD, BD and emotional lability (EL) symptoms.
METHODS: Sixty adult women with ADHD, BD or controls were compared on self-report and interview measures for ADHD symptoms, mania, depression, EL, and impairment.
RESULTS: ADHD interview measures and self-ratings of ADHD symptoms best discriminated between ADHD and BD. Self-report measures of EL and depression showed non-specific enhancement in both clinical groups. BD-specific items may distinguish BD from ADHD if a retrospective time-frame is adopted.
CONCLUSIONS: Using measures which capture specific symptoms of ADHD and chronicity/episodicity of symptoms facilitates the delineation of ADHD from BD in adult women
Towards Equitable, Diverse, and Inclusive science collaborations: The Multimessenger Diversity Network
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