Electrochromic properties of a poly(dithienylfuran) derivative featuring a redox-active dithiin unit

A teraryl monomer containing a 1,4-dithiin-furan central unit has been synthesised and characterised by single crystal X-ray crystallography. The di(thienyl)furan monomer 11 was successfully polymerised electrochemically and shown to possess a lower electrochemical band gap than its terthiophene analogue (1.97 eV cf. 2.11 eV). The electrochromic properties of this polymer proved to be superior to PEDOT, with fast switching and reversible colour transformation at high colour contrast (CE = 212 cm(2) C-1 cf. 183 cm(2) C-1 for PEDOT at 95% optical switch)

Is graphene on copper doped?

Angle-resolved photoemission spectroscopy (ARPES) and X-ray photoemission spectroscopy have been used to characterise epitaxially ordered graphene grown on copper foil by low-pressure chemical vapour deposition. A short vacuum anneal to 200 °C allows observation of ordered low energy electron diffraction patterns. High quality Dirac cones are measured in ARPES with the Dirac point at the Fermi level (undoped graphene). Annealing above 300 °C produces n-type doping in the graphene with up to 350 meV shift in Fermi level, and opens a band gap of around 100 meV. Dirac cone dispersion for graphene on Cu foil after vacuum anneals (left: 200 °C, undoped; right: 500 °C, n-doped). Centre: low energy electron diffraction from graphene on Cu foil after 200 °C anneal. Data from Antares (SOLEIL)

Tracking circadian rhythms of bone mineral deposition in murine calvarial organ cultures

Osteoblasts, which orchestrate the deposition of small apatite crystals through the expression of nucleating proteins, have been shown to also express clock genes associated with the circadian signaling pathway. We hypothesized that protein‐mediated bone mineralization may be linked to circadian oscillator mechanisms functioning in peripheral bone tissue. In this study, Per1 expression in ex vivo neonatal murine calvaria organ cultures was monitored for 6 days using a Per1 ‐ luciferase transgene as a bioluminescent indicator of clock function. Fluctuations in Per1 expression had a period of 25 ± 4 hours ( n  = 14) with early expression at CT09:59 ± 03:37 (CT = circadian time). We also established the kinetics of mineral deposition in developing bone by using noninvasive Raman microscopy to track mineral accumulation in calvarial tissue. The content and quality of newly deposited mineral was continually examined at the interparietal bone/fontanel boundary for a period of 6 days with 1‐hour temporal resolution. Using this approach, mineralization over time exhibited bursts of mineral deposition followed by little or no deposition, which was recurrent with a periodicity of 26.8 ± 9.6 hours. As many as six near‐daily mineralization events were observed in the calvaria before deposition ceased. Earliest mineralization events occurred at CT16:51 ± 03:45, which is 6 hours behind Per1 expression. These findings are consistent with the hypothesis that mineralization in developing bone tissue is regulated by a local circadian oscillator mechanism.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/99084/1/jbmr1924.pd

Pressure evolution of electron dynamics in the superconducting kagome metal CsV3_3Sb5_5

The coexistence of the charge-density wave (CDW) and superconducting phases and their tunability under external pressure remains one of the key points in understanding the electronic structure of $A$V$_3$Sb$_5$ ($A$ = K, Rb, Cs) kagome metals. Here, we employ synchrotron-based infrared spectroscopy assisted by density-functional calculations to study the pressure evolution of the electronic structure at room temperature up to 17 GPa experimentally. The optical spectrum of CsV$_3$Sb$_5$ is characterized by the presence of localized carriers seen as a broad peak at finite frequencies in addition to the conventional metallic Drude response. The pressure dependence of this low-energy peak reflects the re-entrant behavior of superconductivity and may be interpreted in terms of electron-phonon coupling, varying with the growth and shrinkage of the Fermi surface. Moreover, drastic modifications in the low-energy interband absorptions are observed upon the suppression of CDW. These changes are related to the upward shift of the Sb2 $p_x+p_y$ band that eliminates part of the Fermi surface around the $M$-point, whereas band saddle points do not move significantly. These observations shed new light on the mixed electronic and lattice origin of the CDW in CsV$_3$Sb$_5$

Not So Fast: Swimming Behavior of Sailfish during Predator–Prey Interactions using High-Speed Video and Accelerometry

Billfishes are considered among the fastest swimmers in the oceans. Despite early estimates of extremely high speeds, more recent work showed that these predators (e.g., blue marlin) spend most of their time swimming slowly, rarely exceeding 2 m s(-1). Predator-prey interactions provide a context within which one may expect maximal speeds both by predators and prey. Beyond speed, however, an important component determining the outcome of predator-prey encounters is unsteady swimming (i.e., turning and accelerating). Although large predators are faster than their small prey, the latter show higher performance in unsteady swimming. To contrast the evading behaviors of their highly maneuverable prey, sailfish and other large aquatic predators possess morphological adaptations, such as elongated bills, which can be moved more rapidly than the whole body itself, facilitating capture of the prey. Therefore, it is an open question whether such supposedly very fast swimmers do use high-speed bursts when feeding on evasive prey, in addition to using their bill for slashing prey. Here, we measured the swimming behavior of sailfish by using high-frequency accelerometry and high-speed video observations during predator-prey interactions. These measurements allowed analyses of tail beat frequencies to estimate swimming speeds. Our results suggest that sailfish burst at speeds of about 7 m s(-1) and do not exceed swimming speeds of 10 m s(-1) during predator-prey interactions. These speeds are much lower than previous estimates. In addition, the oscillations of the bill during swimming with, and without, extension of the dorsal fin (i.e., the sail) were measured. We suggest that extension of the dorsal fin may allow sailfish to improve the control of the bill and minimize its yaw, hence preventing disturbance of the prey. Therefore, sailfish, like other large predators, may rely mainly on accuracy of movement and the use of the extensions of their bodies, rather than resorting to top speeds when hunting evasive prey

In Situ Transfection by Controlled Release of Lipoplexes Using Acoustic Droplet Vaporization

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/133565/1/adhm201600008_am.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/133565/2/adhm201600008.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/133565/3/adhm201600008-sup-0001-S1.pd