Correlation study of temporal and emission properties of quiescent magnetars

We measured temporal and emission properties of quiescent magnetars using archival Chandra and XMM-Newton data, produced a list of the properties for 17 magnetars, and revisited previously suggested correlations between the properties. Our studies carried out with a larger sample, better spectral characterizations, and more thorough analyses not only confirmed previously-suggested correlations but also found new ones. The observed correlations differ from those seen in other neutron-star populations but generally accord with magnetar models. Specifically, the trends of the intriguing correlations of blackbody luminosity ($L_{\rm BB}$) with the spin-inferred dipole magnetic field strength ($B_{\rm S}$) and characteristic age ($\tau_{\rm c}$) were measured to be $L_{\rm BB}\propto B_{\rm S}^{1.5}$ and $L_{\rm BB}\propto \tau_{\rm c}^{-0.6}$, supporting the twisted magnetosphere and magnetothermal evolution models for magnetars. We report the analysis results and discuss our findings in the context of magnetar models.Comment: 19 pages, 4 figures, accepted for publication in JKA

Facile electrodeposition of high-density CuCo2O4 nanosheets as a high-performance Li-ion battery anode material

High-density CuCo2O4 nanosheets are grown on Ni foam using electrodeposition followed by air annealing for a Li-ion battery anode. The anode exhibits a high discharge capacity of 1244 mAh/g at 0.1 A/g (82% coulombic efficiency) and excellent high-rate performance with 95% capacity retention (1100 mAh/g after 200 cycles at 1 A/g). The outstanding battery performance of the CuCo2O4 anode is attributed to its binder-free direct contact to the current collector and high-density nanosheet morphology. The present experimental findings demonstrate that the electrodeposited binder-free CuCo2O4 material may serve as a safe, low-cost, long-cycle life anode for Li-ion batteries

Chaperone-like protein DAY plays critical roles in photomorphogenesis.

Photomorphogenesis, light-mediated development, is an essential feature of all terrestrial plants. While chloroplast development and brassinosteroid (BR) signaling are known players in photomorphogenesis, proteins that regulate both pathways have yet to be identified. Here we report that DE-ETIOLATION IN THE DARK AND YELLOWING IN THE LIGHT (DAY), a membrane protein containing DnaJ-like domain, plays a dual-role in photomorphogenesis by stabilizing the BR receptor, BRI1, as well as a key enzyme in chlorophyll biosynthesis, POR. DAY localizes to both the endomembrane and chloroplasts via its first transmembrane domain and chloroplast transit peptide, respectively, and interacts with BRI1 and POR in their respective subcellular compartments. Using genetic analysis, we show that DAY acts independently on BR signaling and chlorophyll biogenesis. Collectively, this work uncovers DAY as a factor that simultaneously regulates BR signaling and chloroplast development, revealing a key regulator of photomorphogenesis that acts across cell compartments

Model of undisturbed ground temperature in Northampton, Massachusetts

Climate change is a serious problem caused by fossil fuels. This has led to a global trend of using renewable energies such as geothermal energy, solar energy, and wind energy, as alternatives to fossil fuels. In reaction to climate change, Smith College is respond- ing with their 2030 Carbon Neutrality Plan for carbon mitigation. For thermal loads, Smith College has the on-site District Energy Plan, which involves installing geother- mal heat exchangers on campus. In order to optimize geothermal systems, we need to understand how heat exchangers interact with the ground, hence the need for the undisturbed ground temperature model. The undisturbed ground temperature model was found by calibrating the uncali- brated distributed temperature sensing (DTS) temperature data with a power fit. The undisturbed ground temperature model was found by averaging the calibrated temper- ature data by cable length. The model was then validated with the continental gradient and by using temperature data from different dates and times

CEO Political Ideology and Risk Factor Disclosure

I examine whether and how CEO political ideology affects risk factor disclosure. Since 2005, the Securities and Exchange Commission (SEC) has required U.S. firms to disclose risk factors in their 10-K filings. While prior studies document that this required disclosure increases the information content of financial reports, there is limited evidence on how Chief Executive Officer (CEO) personality traits influence risk factor disclosure. In this paper, I focus on CEOs\u27 political ideology to proxy for their personality traits. Using CEOs\u27 personal political contributions data to capture their political ideology, I find that firms with Republican-leaning CEOs provide less risk factor information than non-Republican-leaning CEOs. Moreover, I show that firms with Republican-leaning CEOs are less likely to use uncertain tone than non-Republican-leaning CEOs. Cross-sectional analyses reveal that these findings are stronger when the CEO has more power over corporate decision-making. I provide empirical evidence that CEO political ideology impacts risk factor disclosure

N-6-methyladenosine-modified RNA acts as a molecular glue that drives liquid-liquid phase separation in plants

Liquid-like condensates are organized by multivalent intrinsically disordered proteins and RNA molecules. We here demonstrate that N-6-methyladenosine (m(6)A)-modified RNA is widespread in establishing diverse plant cell condensates. Several m(6)A-reader proteins contain putative prion-like domains, and the ect2/3/4 mutant exhibited reduced formation of key nuclear and cytoplasmic condensates in Arabidopsis.N

Fast Electrically Driven Capillary Rise Using Overdrive Voltage

Enhancement of response speed (or reduction of response time) is crucial for the commercialization of devices based on electrowetting (EW), such as liquid lenses and reflective displays, and presents one of the main challenges in EW research studies. We demonstrate here that an overdrive EW actuation gives rise to a faster rise of a liquid column between parallel electrodes, compared to a DC EW actuation. Here, DC actuation is actually a simple applied step function, and overdrive is an applied step followed by reduction to a lower voltage. Transient behaviors and response time (i.e., the time required to reach the equilibrium height) of the rising liquid column are explored under different DC and overdrive EW actuations. When the liquid column rises up to a target height by means of an overdrive EW, the response time is reduced to as low as 1/6 of the response time using DC EW. We develop a theoretical model to simulate the EW-driven capillary rise by combining the kinetic equation of capillary flow (i.e., Lucas-Washburn equation) and the dynamic contact angle model considering contact line friction, contact angle hysteresis, contact angle saturation, and the EW effect. This theoretical model accurately predicts the outcome to within a 5% error in regard to the rising behaviors of the liquid column with a low viscosity, under both DC EW and overdrive actuation conditions, except for the early stage (<about 20 ms).1165sciescopu

High-Crystalline Regioregular Polymer Semiconductor by Thermal Treatment for Thickness Tolerance Organic Photovoltaics

To successfully develop a regioregular polymer, poly[4,8-bis(5-(2-hexyldecyl)thiophen-2-yl)benzo[1,2-b:4,5-b &apos;]dithiophene][5,5 &apos;-bis(7-(4-(2-butyloctyl)thiophen-2-yl)-6-fluorobenzo[c][1,2,5]thiadiazol-4-yl)-2,2 &apos;-bithiophene] (PDBD-FBT), a symmetric monomer synthesized in high yield by tin homo-coupling reactions. PDBD-FBT is suitable as a donor material in organic photovoltaics (OPVs) because it shows high crystallinity and strong face-on packing properties. These properties were amplified by thermal annealing (TA). This causes a power conversion efficiency (PCE) enhancement in PDBD-FBT-based OPVs. Using PDBD-FBT as a polymer donor and 2,2 &apos;-((2Z,2 &apos; Z)-((12,13-bis(2-heptylundecyl)-3,9-diundecyl-12,13-dihydro-[1,2,5]thiadiazolo[3,4-e]thieno[2 &apos;&apos;,3 &apos;&apos;:4 &apos;,5 &apos;]thieno[2 &apos;,3 &apos;:4,5]pyrrolo[3,2-g]thieno[2 &apos;,3 &apos;:4,5]thieno[3,2-b]indole-2,10-diyl)bis(methanylylidene))bis(5,6-difluoro-3-oxo-2,3-dihydro-1H-indene-2,1-diylidene))dimalononitrile (Y6-HU) as an electron acceptor, a PCE of 7.91% was achieved without any additive and TA at optimized active layer film thickness of approximately 100 nm. After TA, a PCE of 12.53% was achieved with a 58% increase compared with the reference devices. Owing to the strong crystallinities, trap-assisted recombination occurs by excessively formed grain boundaries; however, efficient exciton dissociation sufficiently covers these drawbacks. Even in the approximately 340 nm-thick film condition, this tendency is more pronounced (73% PCE enhancement is observed from 6.17% to 10.69% of PCE in the without and with TA devices, respectively). Our study demonstrates that it is possible to manufacture thickness-insensitive OPVs based on regioregular polymers with strong crystallinity and face-on characteristics, thereby providing a solution to the thickness variation of large-area organic solar cell modules

Coordination modulated passivation for stable organic-inorganic perovskite solar cells

Despite the recent exceptional rise in power conversion efficiency of perovskite solar cells (PSCs), surface defects and ion migration related instability are still present in PSCs. The chain length and binding energy of the passivation material play important roles in defect passivation, ion migration, moisture stability, and device-performance improvement. We synthesized three sulfonated ammonium compounds and investigated the ef-fect of post-passivation with these compounds on ion-migration and stability. New materials with high binding energy include octylamine (OA) functionalized with sulfanilic acid (OAS), p-toluenesulfonic acid (OAT), and camphorsulfonic acid (OAC). The passivation improves power conversion efficiency (PCE) from 21.06% for the control to 24.37% for the devices treated with OAC. The champion device&apos;s hysteresis index decreased to 0.01 compared to 0.11 for the control device, which is the lowest reported so far. Furthermore, the passivated perovskite films retain over 85% of their initial PCE under 60% relative humidity for 1,600 h, and the device with OAC maintains over 90% of its initial operational long-term device stability without encapsulation for 600 h under 1 sun-illumination