WIYN Open Cluster Study. XXXVIII. Stellar Radial Velocities in the Young Open Cluster M35 (NGC 2168)

We present 5201 radial-velocity measurements of 1144 stars, as part of an ongoing study of the young (150 Myr) open cluster M35 (NGC 2168). We have observed M35 since 1997, using the Hydra Multi-Object Spectrograph on the WIYN 3.5m telescope. Our stellar sample covers main-sequence stars over a magnitude range of 13.0<V<16.5 (1.6 - 0.8 Msun) and extends spatially to a radius of 30 arcminutes (7 pc in projection at a distance of 805 pc or 4 core radii). Due to its youth, M35 provides a sample of late-type stars with a range of rotation periods. Therefore, we analyze the radial-velocity measurement precision as a function of the projected rotational velocity. For narrow-lined stars (v sin i < 10 km/s), the radial velocities have a precision of 0.5 km/s, which degrades to 1.0 km/s for stars with v sin i = 50 km/s. The radial-velocity distribution shows a well-defined cluster peak with a central velocity of -8.16 +/- 0.05 km/s, permitting a clean separation of the cluster and field stars. For stars with >=3 measurements, we derive radial-velocity membership probabilities and identify radial-velocity variables, finding 360 cluster members, 55 of which show significant radial- velocity variability. Using these cluster members, we construct a color-magnitude diagram for our stellar sample cleaned of field star contamination. We also compare the spatial distribution of the single and binary cluster members, finding no evidence for mass segregation in our stellar sample. Accounting for measurement precision, we place an upper limit on the radial-velocity dispersion of the cluster of 0.81 +/- 0.08 km/s. After correcting for undetected binaries, we derive a true radial-velocity dispersion of 0.65 +/- 0.10 km/s.Comment: accepted for publication in A

Corneal Refractive Surgery in Patients with History of Optic Neuritis

Purpose The purpose of this study was to evaluate the risk of recurrence of optic neuritis after corneal refractive surgery in patients with a history of optic neuritis and to examine the safety and efficacy of the procedure in this population. Methods This was a retrospective chart review of patients with a history of optic neuritis who underwent laser-assisted in situ keratomileusis (LASIK) or photorefractive keratectomy (PRK) at a single tertiary center from June 1996 to December 2014. Fifteen eyes of 14 patients were included in this study. Visual acuity before and after the surgery was recorded. Patients were followed-up for over five years postoperatively for the recurrence of optic neuritis. Results The average LogMAR best corrected visual acuity (BCVA) preoperatively was 0.12 ± 0.19 (–0.10 to 0.60) and postoperatively was 0.06 ± 0.10 (–0.10 to 0.30). No eyes lost lines of BCVA. The average LogMAR uncorrected distance visual acuity (UDVA) after surgery was 0.12 ± 0.13 (0.00 to 0.48). Twenty-eight percent of patients reached a UDVA of 20/20 or better after refractive surgery. Optic neuritis recurred in 3/15 (20%) eyes and 3/14 patients (21%). Conclusion While corneal refractive procedures appear safe in patients with a history of optic neuritis, our data suggest that their efficacy may be reduced

Corneal Refractive Surgery in Patients with History of Optic Neuritis

Purpose: The purpose of this study was to evaluate the risk of recurrence of optic neuritis after corneal refractive surgery in patients with a history of optic neuritis and to examine the safety and efficacy of the procedure in this population. Methods: This was a retrospective chart review of patients with a history of optic neuritis who underwent laser-assisted in situ keratomileusis (LASIK) or photorefractive keratectomy (PRK) at a single tertiary center from June 1996 to December 2014. Fifteen eyes of 14 patients were included in this study. Visual acuity before and after the surgery was recorded. Patients were followed-up for over five years postoperatively for the recurrence of optic neuritis. Results: The average LogMAR best corrected visual acuity (BCVA) preoperatively was 0.12 ± 0.19 (–0.10 to 0.60) and postoperatively was 0.06 ± 0.10 (–0.10 to 0.30). No eyes lost lines of BCVA. The average LogMAR uncorrected distance visual acuity (UDVA) after surgery was 0.12 ± 0.13 (0.00 to 0.48). Twenty-eight percent of patients reached a UDVA of 20/20 or better after refractive surgery. Optic neuritis recurred in 3/15 (20%) eyes and 3/14 patients (21%). Conclusion: While corneal refractive procedures appear safe in patients with a history of optic neuritis, our data suggest that their efficacy may be reduced

Astigmatic correction with implantation of a light adjustable vs monofocal lens: a single site analysis of a randomized controlled trial

AIM To evaluate the light adjustable lens (LAL) vs a standard monofocal lens in achieving target astigmatic refraction and improving postoperative uncorrected distance visual acuity (UDVA). METHODS This randomized controlled clinical trial included 40 patients with pre-existing astigmatism and visually significant cataract. Twenty-eight patients received the LAL and 12 control patients received a monofocal intraocular lens (IOL) after cataract extraction at a single institution. The patients with the LAL underwent adjustment by ultraviolet (UV) light postoperatively plus subsequent lock-in procedures and all patients returned to clinic for follow up of study parameters at 6, 9, and 12mo. Manifest refraction, distance visual acuity, and adverse events were recorded at each visit. RESULTS The mean cylinder before adjustment in eyes with the LAL was -0.89±0.58 D (-2.00 to 0.00 D) and -0.34±0.34 D (-1.25 to 0.00 D) after lock-in (P=1.68x10−8). The mean cylinder in patients with the monofocal lens was -1.00±0.32 D (-1.50 to -0.50 D) at 17-21d postoperatively, which was statistically different from the LAL cylinder post lock-in (P=1.43x10−6). UDVA in the LAL group was 20/20 or better in 79% of patients post lock-in with good stability over 12mo compared with 33% of the control patients with UDVA of 20/20 or better. CONCLUSION These results demonstrate that the LAL is more effective in achieving target refractions and improving postoperative UDVA in patients with pre-existing corneal astigmatism than a standard monofocal lens

Nanoliter Reactors Improve Multiple Displacement Amplification of Genomes from Single Cells

Since only a small fraction of environmental bacteria are amenable to laboratory culture, there is great interest in genomic sequencing directly from single cells. Sufficient DNA for sequencing can be obtained from one cell by the Multiple Displacement Amplification (MDA) method, thereby eliminating the need to develop culture methods. Here we used a microfluidic device to isolate individual Escherichia coli and amplify genomic DNA by MDA in 60-nl reactions. Our results confirm a report that reduced MDA reaction volume lowers nonspecific synthesis that can result from contaminant DNA templates and unfavourable interaction between primers. The quality of the genome amplification was assessed by qPCR and compared favourably to single-cell amplifications performed in standard 50-μl volumes. Amplification bias was greatly reduced in nanoliter volumes, thereby providing a more even representation of all sequences. Single-cell amplicons from both microliter and nanoliter volumes provided high-quality sequence data by high-throughput pyrosequencing, thereby demonstrating a straightforward route to sequencing genomes from single cells

Revisiting histories of anti-racist thought and activism

This piece reconsiders histories of anti-racist thought and practice, including the linkages between anti-racisms and other traditions of liberatory thought. We argue that anti-racism should be understood as a strand in radical thought linking internationalism, institutional critique and street activism, in the process interfeeding with other social movements. The traditions of anti-racist thought discussed in this special issue exemplify these cross-cutting influences

Expression and trans-specific polymorphism of self-incompatibility RNases in Coffea (Rubiaceae)

Self-incompatibility (SI) is widespread in the angiosperms, but identifying the biochemical components of SI mechanisms has proven to be difficult in most lineages. Coffea (coffee; Rubiaceae) is a genus of old-world tropical understory trees in which the vast majority of diploid species utilize a mechanism of gametophytic self-incompatibility (GSI). The S-RNase GSI system was one of the first SI mechanisms to be biochemically characterized, and likely represents the ancestral Eudicot condition as evidenced by its functional characterization in both asterid (Solanaceae, Plantaginaceae) and rosid (Rosaceae) lineages. The S-RNase GSI mechanism employs the activity of class III RNase T2 proteins to terminate the growth of "self" pollen tubes. Here, we investigate the mechanism of Coffea GSI and specifically examine the potential for homology to S-RNase GSI by sequencing class III RNase T2 genes in populations of 14 African and Madagascan Coffea species and the closely related self-compatible species Psilanthus ebracteolatus. Phylogenetic analyses of these sequences aligned to a diverse sample of plant RNase T2 genes show that the Coffea genome contains at least three class III RNase T2 genes. Patterns of tissue-specific gene expression identify one of these RNase T2 genes as the putative Coffea S-RNase gene. We show that populations of SI Coffea are remarkably polymorphic for putative S-RNase alleles, and exhibit a persistent pattern of trans-specific polymorphism characteristic of all S-RNase genes previously isolated from GSI Eudicot lineages. We thus conclude that Coffea GSI is most likely homologous to the classic Eudicot S-RNase system, which was retained since the divergence of the Rubiaceae lineage from an ancient SI Eudicot ancestor, nearly 90 million years ago.United States National Science Foundation [0849186]; Society of Systematic Biologists; American Society of Plant Taxonomists; Duke University Graduate Schoolinfo:eu-repo/semantics/publishedVersio

WIYN Open Cluster Study. XLVIII. The Hard-Binary Population of NGC 188

(abridged) We present an in-depth study of the hard-binary population of the old (7 Gyr) open cluster NGC 188. The main-sequence solar-type hard binaries in NGC 188 are nearly indistinguishable from similar binaries in the Galactic field. We find a global solar-type main-sequence hard-binary frequency in NGC 188 of 29 +/- 3 % for binaries with periods less than 10^4 days. For main-sequence hard binaries in the cluster we observe a log-period distribution that rises towards our detection limit, a roughly Gaussian eccentricity distribution centered on e = 0.35 (for binaries with periods longer than the circularization period), and a secondary-mass distribution that rises towards lower-mass companions. Importantly, the NGC 188 blue straggler binaries show significantly different characteristics than the solar-type main sequence binaries in NGC 188. We observe a blue straggler hard-binary frequency of 76 +/- 19 %, three times that of the main sequence. The blue straggler binary eccentricity - log period distribution is distinct from that of the main sequence at the 99% confidence level, with the majority of the blue straggler binaries having periods of order 1000 days and lower eccentricities. The secondary-mass distribution for these long-period blue straggler binaries is narrow and peaked with a mean value of about 0.5 Msun. Predictions for mass-transfer products are most closely consistent with the binary properties of these NGC 188 blue stragglers, which comprise two-thirds of the blue straggler population. Additionally we compare the NGC 188 binaries to those evolved within the sophisticated Hurley et al. (2005) N-body open cluster simulation. We find that additional simulations with initial conditions that are better motivated by observations are necessary to properly investigate the dynamical evolution of a rich binary population in open clusters like NGC 188.Comment: 23 pages, 22 figures, accepted for publication in A

Global estimates of mortality associated with long-term exposure to outdoor fine particulate matter.

Exposure to ambient fine particulate matter (PM2.5) is a major global health concern. Quantitative estimates of attributable mortality are based on disease-specific hazard ratio models that incorporate risk information from multiple PM2.5 sources (outdoor and indoor air pollution from use of solid fuels and secondhand and active smoking), requiring assumptions about equivalent exposure and toxicity. We relax these contentious assumptions by constructing a PM2.5-mortality hazard ratio function based only on cohort studies of outdoor air pollution that covers the global exposure range. We modeled the shape of the association between PM2.5 and nonaccidental mortality using data from 41 cohorts from 16 countries-the Global Exposure Mortality Model (GEMM). We then constructed GEMMs for five specific causes of death examined by the global burden of disease (GBD). The GEMM predicts 8.9 million [95% confidence interval (CI): 7.5-10.3] deaths in 2015, a figure 30% larger than that predicted by the sum of deaths among the five specific causes (6.9; 95% CI: 4.9-8.5) and 120% larger than the risk function used in the GBD (4.0; 95% CI: 3.3-4.8). Differences between the GEMM and GBD risk functions are larger for a 20% reduction in concentrations, with the GEMM predicting 220% higher excess deaths. These results suggest that PM2.5 exposure may be related to additional causes of death than the five considered by the GBD and that incorporation of risk information from other, nonoutdoor, particle sources leads to underestimation of disease burden, especially at higher concentrations