Optogenetic control of nerve growth

Due to the limited regenerative ability of neural tissue, a diverse set of biochemical and biophysical cues for increasing nerve growth has been investigated, including neurotrophic factors, topography, and electrical stimulation. In this report, we explore optogenetic control of neurite growth as a cell-specific alternative to electrical stimulation. By investigating a broad range of optical stimulation parameters on dorsal root ganglia (DRGs) expressing channelrhodopsin 2 (ChR2), we identified conditions that enhance neurite outgrowth by three-fold as compared to unstimulated or wild-type (WT) controls. Furthermore, optogenetic stimulation of ChR2 expressing DRGs induces directional outgrowth in WT DRGs co-cultured within a 10 mm vicinity of the optically sensitive ganglia. This observed enhancement and polarization of neurite growth was accompanied by an increased expression of neural growth and brain derived neurotrophic factors (NGF, BDNF). This work highlights the potential for implementing optogenetics to drive nerve growth in specific cell populations.Charles Stark Draper Laboratory (University Research and Development Grant)National Science Foundation (U.S.). Materials Research Science and Engineering Centers (Program) (Award DMR-0819762)National Science Foundation (U.S.) (CAREER Award CBET-1253890)Simons FoundationKorean Government Scholarship Program for Study Oversea

'Sent down? Called up?': Exploring the roller coaster of loans and re-assignments in professional hockey

Athletes constantly face transitions in their sporting careers, which can influence the quality of their performance and well-being. The purpose of the study is to explore professional hockey players’ lived experiences with being called up and sent down in organizations. For example, an athlete can play in the National Hockey League (NHL) and is then sent down to their affiliated team in the American Hockey League (AHL) for a variety of reasons. The study utilized a phenomenological approach to understand athletes lived experiences with being called up and sent down, this allowed the researcher to move beyond brief descriptions toward understanding this specific transition athletes face. Semi-structured interviews were audio-recorded and transcribed verbatim, which occurred with six current hockey players (five current professional athletes and one competitive athlete). Data-analysis followed a two-phase process analysis to determine themes and patterns within each interview and then compared patterns across interviews to see what is common across interviews. The results were presented in three clusters such as the performance and well-being of an athlete, external influences on career, and interpretations of experiences. Further research is needed to explore the impact that loaning can have on an athlete and their well-being

Chandra Smells a RRAT: X-ray Detection of a Rotating Radio Transient

"Rotating RAdio Transients" (RRATs) are a newly discovered astronomical phenomenon, characterised by occasional brief radio bursts, with average intervals between bursts ranging from minutes to hours. The burst spacings allow identification of periodicities, which fall in the range 0.4 to 7 seconds. The RRATs thus seem to be rotating neutron stars, albeit with properties very different from the rest of the population. We here present the serendipitous detection with the Chandra X-ray Observatory of a bright point-like X-ray source coincident with one of the RRATs. We discuss the temporal and spectral properties of this X-ray emission, consider counterparts in other wavebands, and interpret these results in the context of possible explanations for the RRAT population.Comment: 5 pages, 2 b/w figures, 1 color figure. To appear in the proceedings of "Isolated Neutron Stars", Astrophysics & Space Science, in pres

Bioelectronic medicines: a research roadmap

Realizing the vision of a new class of medicines based on modulating the electrical signalling patterns of the peripheral nervous system needs a firm research foundation. Here, an interdisciplinary community puts forward a research roadmap for the next 5 years

The Host Galaxy and Redshift of the Repeating Fast Radio Burst FRB 121102

The precise localization of the repeating fast radio burst (FRB 121102) has provided the first unambiguous association (chance coincidence probability $p\lesssim3\times10^{-4}$) of an FRB with an optical and persistent radio counterpart. We report on optical imaging and spectroscopy of the counterpart and find that it is an extended ($0.6^{\prime\prime}-0.8^{\prime\prime}$) object displaying prominent Balmer and [OIII] emission lines. Based on the spectrum and emission line ratios, we classify the counterpart as a low-metallicity, star-forming, $m_{r^\prime} = 25.1$ AB mag dwarf galaxy at a redshift of $z=0.19273(8)$, corresponding to a luminosity distance of 972 Mpc. From the angular size, the redshift, and luminosity, we estimate the host galaxy to have a diameter $\lesssim4$ kpc and a stellar mass of $M_*\sim4-7\times 10^{7}\,M_\odot$, assuming a mass-to-light ratio between 2 to 3$\,M_\odot\,L_\odot^{-1}$. Based on the H$\alpha$ flux, we estimate the star formation rate of the host to be $0.4\,M_\odot\,\mathrm{yr^{-1}}$ and a substantial host dispersion measure depth $\lesssim 324\,\mathrm{pc\,cm^{-3}}$. The net dispersion measure contribution of the host galaxy to FRB 121102 is likely to be lower than this value depending on geometrical factors. We show that the persistent radio source at FRB 121102's location reported by Marcote et al (2017) is offset from the galaxy's center of light by $\sim$200 mas and the host galaxy does not show optical signatures for AGN activity. If FRB 121102 is typical of the wider FRB population and if future interferometric localizations preferentially find them in dwarf galaxies with low metallicities and prominent emission lines, they would share such a preference with long gamma ray bursts and superluminous supernovae.Comment: 12 pages, 3 figures, Published in ApJ Letters. V2: Corrected mistake in author lis

Campaigning During COVID-19: How Texas Republicans Navigated the 2020 Election

The COVID-19 pandemic caused major disruptions to political campaigns during the 2020 election. There was a stark contrast between how the two major parties approached campaigning during COVID-19, including the election in Texas, a deep red state that some thought might present opportunities for Democratic Party candidates. Using interviews with 13 campaign operatives, this study examines how Republican candidates in Texas navigated their campaigns in the context of a pandemic. Our results suggest the unique context of campaigning during COVID-19 gave Republicans key advantages over Democrats. Decisions to embrace a more organic, bottom-up approach led to more flexible campaign strategies. Democratic Party candidates followed the lead of Joe Biden’s presidential campaign and mostly refrained from direct voter contact, like door knocking. Through experimentation, many Republican campaigns felt comfortable embracing a ground game and deployed complete field operations. Consultants argued this played an important role in helping Texas Republicans exceed expectations

BBF RFC 112: Synthetic Biology Open Language (SBOL) Version 2.1.0

BBF RFC 112 (the SBOL 2.1.0 standard) replaces BBF RFC 108 (the SBOL 2.0 standard), as well as the minor update SBOL 2.0.1.The Synthetic Biology Open Language (SBOL) has been developed as a standard to support the specification and exchange of biological design information