Indole-tethered ynones form an intramolecular electron donor-acceptor complex that can undergo visible-light-induced charge transfer to promote thiyl radical generation from thiols. This initiates a ...novel radical chain sequence, based on dearomatising spirocyclisation with concomitant C-S bond formation. Sulfur-containing spirocycles are formed in high yields using this simple and mild synthetic protocol, in which neither transition metal catalysts nor photocatalysts are required. The proposed mechanism is supported by various mechanistic studies, and the unusual radical initiation mode represents only the second report of the use of an intramolecular electron donor-acceptor complex in synthesis.
Indole-tethered ynones form an intramolecular electron donor-acceptor complex that can undergo visible-light-induced charge transfer to promote thiyl radical generation from thiols.
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IJS, KILJ, NUK, UL, UM, UPUK
We describe the results of a search for time variability of the fine structure constant alpha using absorption systems in the spectra of distant quasars. Three large optical data sets and two 21 cm ...and mm absorption systems provide four independent samples, spanning approximately 23% to 87% of the age of the universe. Each sample yields a smaller alpha in the past and the optical sample shows a 4 sigma deviation: Delta alpha/alpha = -0.72+/-0.18 x 10(-5) over the redshift range 0.5<z<3.5. We find no systematic effects which can explain our results. The only potentially significant systematic effects push Delta alpha/alpha towards positive values; i.e., our results would become more significant were we to correct for them.
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CMK, CTK, FMFMET, IJS, NUK, PNG, UM
The goal of the Complex Trait Consortium is to promote the development of resources that can be used to understand, treat and ultimately prevent pervasive human diseases. Existing and proposed mouse ...resources that are optimized to study the actions of isolated genetic loci on a fixed background are less effective for studying intact polygenic networks and interactions among genes, environments, pathogens and other factors. The Collaborative Cross will provide a common reference panel specifically designed for the integrative analysis of complex systems and will change the way we approach human health and disease.
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DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
A systematic review and meta-analysis were conducted to determine the efficacy of selective dry-cow antimicrobial therapy compared to blanket therapy (all quarters/all cows). Controlled trials were ...eligible if any of the following were assessed: incidence of clinical mastitis during the first 30 DIM, frequency of intramammary infection (IMI) at calving, or frequency of IMI during the first 30 DIM. From 3480 identified records, nine trials were data extracted for IMI at calving. There was an insufficient number of trials to conduct meta-analysis for the other outcomes. Risk of IMI at calving in selectively treated cows was higher than blanket therapy (RR = 1.34, 95% CI = 1.13, 1.16), but substantial heterogeneity was present (I2 = 58%). Subgroup analysis showed that, for trials using internal teat sealants, there was no difference in IMI risk at calving between groups, and no heterogeneity was present. For trials not using internal teat sealants, there was an increased risk in cows assigned to a selective dry-cow therapy protocol, compared to blanket treatment, with substantial heterogeneity in this subgroup. However, the small number of trials and heterogeneity in the subgroup without internal teat sealants suggests that the relative risk between treatments may differ from the determined point estimates based on other unmeasured factors.
Cognitive sequelae often occur after acute carbon monoxide poisoning. This double-blind, randomized trial assigned subjects either to three sessions in a hyperbaric-oxygen chamber or to one ...normobaric-oxygen treatment plus two sessions of exposure to normobaric room air, all administered within 24 hours after the end of exposure to carbon monoxide. Cognitive sequelae six weeks later were less frequent among persons who received hyperbaric-oxygen therapy (25.0 percent) than among those who received normobaric-oxygen treatment (46.1 percent, P=0.007). Differences were sustained 12 months after the episode of acute carbon monoxide poisoning.
The results of this double-blind trial support the use of hyperbaric oxygen.
Carbon monoxide poisoning is a serious health problem
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resulting in approximately 40,000 visits to the emergency department annually in the United States.
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Unfavorable cognitive sequelae (problems with memory, attention or concentration, and affect) can occur immediately after exposure and persist or can be delayed, but they generally occur within 20 days after carbon monoxide poisoning.
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Cognitive sequelae lasting one month
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or more
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appear to occur in 25 to 50 percent of patients with loss of consciousness or with carboxyhemoglobin levels greater than 25 percent.
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The recommended treatment for acute carbon monoxide poisoning . . .
Introduction. The aim of this study was to determine the prevalence of burnout, and of associated factors, amongst family doctors (FDs) in European countries. Methodology. A cross-sectional survey of ...FDs was conducted using a custom-designed and validated questionnaire which incorporated the Maslach Burnout Inventory Human Services Survey (MBI-HSS) as well as questions about demographic factors, working experience, health, lifestyle and job satisfaction. MBI-HSS scores were analysed in the three dimensions of emotional exhaustion (EE), depersonalization (DP) and personal accomplishment (PA). Results. Almost 3500 questionnaires were distributed in 12 European countries, and 1393 were returned to give a response rate of 41%. In terms of burnout, 43% of respondents scored high for EE burnout, 35% for DP and 32% for PA, with 12% scoring high burnout in all three dimensions. Just over one-third of doctors did not score high for burnout in any dimension. High burnout was found to be strongly associated with several of the variables under study, especially those relative to respondents’ country of residence and European region, job satisfaction, intention to change job, sick leave utilization, the (ab)use of alcohol, tobacco and psychotropic medication, younger age and male sex. Conclusions. Burnout seems to be a common problem in FDs across Europe and is associated with personal and workload indicators, and especially job satisfaction, intention to change job and the (ab)use of alcohol, tobacco and medication. The study questionnaire appears to be a valid tool to measure burnout in FDs. Recommendations for employment conditions of FDs and future research are made, and suggestions for improving the instrument are listed.
An experimental search for variation in the fundamental coupling constants is strongly motivated by modern high-energy physics theories. Comparison of quasar (QSO) absorption-line spectra with ...laboratory spectra provides a sensitive probe for variability of the fine-structure constant, α, over cosmological time-scales. We have previously developed and applied a new method providing an order-of-magnitude gain in precision over previous optical astrophysical constraints. Here we extend that work by including new quasar spectra of damped Lyman-α absorption systems. We also reanalyse our previous lower-redshift data and confirm our initial results. The constraints on α come from simultaneous fitting of absorption lines of subsets of the following species: Mg-i, Mg-ii, Al-ii, Al-iii, Si-ii, Cr-ii, Fe-ii, Ni-ii and Zn-ii. We present a detailed description of our methods and results based on an analysis of 49 quasar absorption systems (towards 28 QSOs) covering the redshift range . There is statistical evidence for a smaller α at earlier epochs: The new and original samples are independent but separately yield consistent and significant non-zero values of . We summarize the results of a thorough investigation of systematic effects published in a companion paper. The value we quote above is the raw value, not corrected for any of these systematic effects. The only significant systematic effects so far identified, if removed from our data, would lead to a more significant deviation of from zero.
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BFBNIB, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UL, UM, UPUK
Winter climate is expected to change under future climate scenarios, yet the majority of winter ecology research is focused in cold-climate ecosystems. In many temperate systems, it is unclear how ...winter climate relates to biotic responses during the growing season. The objective of this study was to examine how winter weather relates to plant and animal communities in a variety of terrestrial ecosystems ranging from warm deserts to alpine tundra. Specifically, we examined the association between winter weather and plant phenology, plant species richness, consumer abundance, and consumer richness in 11 terrestrial ecosystems associated with the U.S. Long-Term Ecological Research (LTER) Network. To varying degrees, winter precipitation and temperature were correlated with all biotic response variables. Bud break was tightly aligned with end of winter temperatures. For half the sites, winter weather was a better predictor of plant species richness than growing season weather. Warmer winters were correlated with lower consumer abundances in both temperate and alpine systems. Our findings suggest winter weather may have a strong influence on biotic activity during the growing season and should be considered in future studies investigating the effects of climate change on both alpine and temperate systems.
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BFBNIB, FZAB, GIS, IJS, INZLJ, KILJ, NLZOH, NMLJ, NUK, OILJ, PNG, SAZU, SBCE, SBMB, UL, UM, UPUK, ZRSKP
A thorough understanding of gender differences in physical activity is critical to effective promotion of active living in older adults.
To examine gender and age differences in levels, types and ...locations of physical activity.
Cross-sectional observation.
Car-dependent urban and rural neighborhoods in Worcester County, Massachusetts, USA.
111 men and 103 women aged 65 years and older.
From 2012 to 2014, participants were queried on type, frequency and location of physical activity. Participants wore an accelerometer for 7 consecutive days.
Compared to women, men had a higher mean daily step count (mean (SD) 4385 (2122) men vs. 3671(1723) women, p=0.008). Men reported higher frequencies of any physical activity and moderate-to-vigorous physical activity, and a lower frequency of physical activity inside the home. Mean daily step counts and frequency of physical activity outside the home decreased progressively with age for both men and women. Women had a sharper decline in frequencies of self-reported physical activity. Men had a significant decrease in utilitarian walking, which women did not (p=0.07). Among participants who reported participation in any physical activity (n=190), more women indicated exercising indoors more often (59% vs. 44%, p=0.04). The three most commonly cited locations for physical activity away from home for both genders were streets or sidewalks, shopping malls, and membership-only facilities (e.g., YMCA or YWCA). The most common types of physical activity, performed at least once in a typical month, with over 40% of both genders reporting, included light housework, brisk walking, leisurely walking, and stretching.
Levels, types and location preferences of physical activity differed substantially by gender. Levels of physical activity decreased progressively with age, with greater decline among women. Consideration of these gender differences is necessary to improve the effectiveness of active living promotion programs among older adults.
A systematic review and network meta-analysis were conducted to assess the relative efficacy of internal or external teat sealants given at dry-off in dairy cattle. Controlled trials were eligible if ...they assessed the use of internal or external teat sealants, with or without concurrent antimicrobial therapy, compared to no treatment or an alternative treatment, and measured one or more of the following outcomes: incidence of intramammary infection (IMI) at calving, IMI during the first 30 days in milk (DIM), or clinical mastitis during the first 30 DIM. Risk of bias was based on the Cochrane Risk of Bias 2.0 tool with modified signaling questions. From 2280 initially identified records, 32 trials had data extracted for one or more outcomes. Network meta-analysis was conducted for IMI at calving. Use of an internal teat sealant (bismuth subnitrate) significantly reduced the risk of new IMI at calving compared to non-treated controls (RR = 0.36, 95% CI 0.25-0.72). For comparisons between antimicrobial and teat sealant groups, concerns regarding precision were seen. Synthesis of the primary research identified important challenges related to the comparability of outcomes, replication and connection of interventions, and quality of reporting of study conduct.
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