Cellulose triacetate, thin film dielectric capacitor

Very thin films of cellulose triacetate are cast from a solution containing a small amount of high boiling temperature, non-solvent which evaporates last and lifts the film from the casting surface. Stretched, oriented, crystallized films have high electrical breakdown properties. Metallized films less than about 2 microns in thickness form self-healing electrodes for high energy density, pulsed power capacitors. Thicker films can be utilized as a dielectric for a capacitor

Cyanoresin, cyanoresin/cellulose triacetate blends for thin film, dielectric capacitors

Non-brittle dielectric films are formed by blending a cyanoresin such as cyanoethyl, hydroxyethyl cellulose (CRE) with a compatible, more crystalline resin such as cellulose triacetate. The electrical breakdown strength of the blend is increased by orienting the films by uniaxial or biaxial stretching. Blends of high molecular weight CRE with high molecular weight cyanoethyl cellulose (CRC) provide films with high dielectric constants

Cellulose triacetate, thin film dielectric capacitor

Very thin films of cellulose triacetate are cast from a solution containing a small amount of high boiling temperature, non-solvent which evaporates last and lifts the film from the casting surface. Stretched, oriented, crystallized films have high electrical breakdown properties. Metallized films less than about 2 microns in thickness form self-healing electrodes for high energy density, pulsed power capacitors. Thicker films can be utilized as a dielectric for a capacitor

Cyanoresin, cyanoresin/cellulose triacetate blends for thin film, dielectric capacitors

Non brittle dielectric films are formed by blending a cyanoresin such as cyanoethyl, hydroxyethyl cellulose (CRE) with a compatible, more crystalline resin such as cellulose triacetate. The electrical breakdown strength of the blend is increased by orienting the films by uniaxial or biaxial stretching. Blends of high molecular weight CRE with high molecular weight cyanoethyl cellulose (CRC) provide films with high dielectric constants

The GALEX View of "Boyajian's Star" (KIC 8462852)

The enigmatic star KIC 8462852, informally known as "Boyajian's Star", has exhibited unexplained variability from both short timescale (days) dimming events, and years-long fading in the Kepler mission. No single physical mechanism has successfully explained these observations to date. Here we investigate the ultraviolet variability of KIC 8462852 on a range of timescales using data from the GALEX mission that occurred contemporaneously with the Kepler mission. The wide wavelength baseline between the Kepler and GALEX data provides a unique constraint on the nature of the variability. Using 1600 seconds of photon-counting data from four GALEX visits spread over 70 days in 2011, we find no coherent NUV variability in the system on 10-100 second or months timescales. Comparing the integrated flux from these 2011 visits to the 2012 NUV flux published in the GALEX-CAUSE Kepler survey, we find a 3% decrease in brightness for KIC 8462852. We find this level of variability is significant, but not necessarily unusual for stars of similar spectral type in the GALEX data. This decrease coincides with the secular optical fading reported by Montet & Simon (2016). We find the multi-wavelength variability is somewhat inconsistent with typical interstellar dust absorption, but instead favors a R$_V$ = 5.0 $\pm$ 0.9 reddening law potentially from circumstellar dust.Comment: 8 pages, 4 figures, ApJ Accepte

Histological Transformation to Gliosarcoma With Combined BRAF/MEK Inhibition in BRAF V600E Mutated Glioblastoma

The identification of BRAF V600 mutation in multiple cancers beyond melanoma and the development of combined BRAF and MEK targeting agents have altered the landscape of tissue-agnostic precision oncology therapies with an impact on survival outcomes. Despite initial efficacy, resistance emerges, and it is pertinent to identify putative resistance mechanisms. We report a case of recurrent glioblastoma (GBM) harboring BRAF V600E alteration who initially responded to combined BRAF + MEK inhibition and subsequently developed treatment resistance by histological transformation to gliosarcoma and acquisition of oncogenic KRAS G12D and an NF1 L1083R mutation. This documented case represents an initial evidence of a developing phenomenon in cancer research as it provides the first evidence of an emergent KRAS G12D/NF1 L1083R aberration with histological transformation occurring concurrently with primary BRAF V600E-altered glioblastoma as a previously unrecognized acquired mechanism of resistance in the setting of combined BRAF and MEK inhibition. This novel finding not only sheds new light on the RAS/MAPK pathway but also highlights the potential for morphological transformation to gliosarcoma, underscoring the critical need for further investigation in this area

Fundamental parameters, integrated RGB mass loss and dust production in the Galactic globular cluster 47 Tucanae

Fundamental parameters and time-evolution of mass loss are investigated for post-main-sequence stars in the Galactic globular cluster 47 Tucanae (NGC 104). This is accomplished by fitting spectral energy distributions (SEDs) to existing optical and infrared photometry and spectroscopy, to produce a true Hertzsprung--Russell diagram. We confirm the cluster's distance as 4611 (+213, -200) pc and age as 12 +/- 1 Gyr. Horizontal branch models appear to confirm that no more RGB mass loss occurs in 47 Tuc than in the more-metal-poor omega Centauri, though difficulties arise due to inconsistencies between the models. Using our SEDs, we identify those stars which exhibit infrared excess, finding excess only among the brightest giants: dusty mass loss begins at a luminosity of ~ 1000 Lsun, becoming ubiquitous above 2000 Lsun. Recent claims of dust production around lower-luminosity giants cannot be reproduced, despite using the same archival Spitzer imagery.Comment: 22 pages, 17 figures, accepted ApJ