191 research outputs found
The functional significance of dental and mandibular reduction in Homo: A catarrhine perspective.
The reduction in dental size and mandibular robusticity is regarded as a major trend in human evolution, traditionally considered the result of the peculiar extra-oral food processing skills of Homo. The use of stone tools and fire would have allowed our ancestors to chew softer food in smaller bite size, thus relaxing the selective pressures to keep a large dentition and a robust lower jaw. This perspective assumes that differences in dental size and mandibular robusticity in hominins represent functional dissimilarities. This study uses a catarrhine comparative approach to test this fundamental assumption of the hypotheses on dental and mandibular reduction in Homo. A sample of extant catarrhines and fossil hominins was used to test for correlations between dental size, mandibular robusticity, and dietary proxies, the latter include diet quality, diet heterogeneity, feeding time, and microwear variables. The effects of phylogeny and body size were considered. Findings support the association between technological developments in Homo and reduction in incisor size and mandibular corpus robusticity, though not for premolar, molar size, and symphyseal robusticity. These results challenge the functional interpretation of postcanine reduction and symphyseal changes in the genus Homo
Chandra Observations of the Cl1604 Supercluster at z=0.9: Evidence for an Overdensity of Active Galactic Nuclei
We present the results of Chandra observations of the Cl1604 supercluster at
z~0.9. The system is the largest structure mapped at redshifts approaching
unity, containing at least eight spectroscopically confirmed galaxy clusters
and groups. Using two 50-ksec ACIS-I pointings we examine both the X-ray point
source population and the diffuse emission from individual clusters in the
system. We find a 2.5\sigma excess of point sources detected in the hard band
(2-10 keV) relative to the number of sources found in blank fields observed by
Chandra. No such excess is observed in the soft band (0.5-2 keV). The hard-band
source density is 1.47 times greater than that of a blank field, in agreement
with the previously reported correlation between overdensity amplitude and
cluster redshift. Using a maximum likelihood technique we have matched 112 of
the 161 detected X-ray point sources to optical counterparts and found 15
sources that are associated with the supercluster. All 15 sources have
rest-frame luminosities consistent with emission from active galactic nuclei
(AGN). We find that the supercluster AGN largely avoid the densest regions of
the system and are instead distributed on the outskirts of massive clusters or
within poorer clusters and groups. We have also detected diffuse emission from
two of the eight clusters and groups in the system, clusters Cl1604+4304 and
Cl1604+4314. The systems have bolometric luminosities of 1.43x10^44 and
8.20x10^43 h70^-2 erg s^-1 and gas temperatures of 3.50 (+1.82-1.08) and 1.64
(+0.65-0.45) keV, respectively. Using updated velocity dispersions, we compare
the properties of these systems to the cluster scaling relations followed by
other X-ray and optically selected galaxy clusters at high redshift.Comment: 24 pages, 14 figures, submitted to Ap
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Spatially Resolved Study of Backscattering in the Quantum Spin Hall State
Challenges in Columbia River Fisheries Conservation: A Response to Duda et al.
The salmonid fisheries of the Columbia River Basin (CRB) have enormous socioeconomic, cultural, and ecological importance to numerous diverse stakeholders (eg state, federal, tribal, nonprofit), and there are a wide array of opinions and perspectives on how these fisheries should be managed. Although we appreciate Duda et al.\u27s commentary, it offers only one perspective of many in this context. The objective of our paper (Hand et al. 2018) was to provide justification for “the importance of social–ecological perspectives when communicating conservation values and goals, and the role of independent science in guiding management policy and practice for salmonids in the CRB”. However, we did not intend to strictly advocate for a single course of action, and the available space within our paper\u27s Panel 1 limited us from engaging in a thorough ecological debate
LSST Science Book, Version 2.0
A survey that can cover the sky in optical bands over wide fields to faint
magnitudes with a fast cadence will enable many of the exciting science
opportunities of the next decade. The Large Synoptic Survey Telescope (LSST)
will have an effective aperture of 6.7 meters and an imaging camera with field
of view of 9.6 deg^2, and will be devoted to a ten-year imaging survey over
20,000 deg^2 south of +15 deg. Each pointing will be imaged 2000 times with
fifteen second exposures in six broad bands from 0.35 to 1.1 microns, to a
total point-source depth of r~27.5. The LSST Science Book describes the basic
parameters of the LSST hardware, software, and observing plans. The book
discusses educational and outreach opportunities, then goes on to describe a
broad range of science that LSST will revolutionize: mapping the inner and
outer Solar System, stellar populations in the Milky Way and nearby galaxies,
the structure of the Milky Way disk and halo and other objects in the Local
Volume, transient and variable objects both at low and high redshift, and the
properties of normal and active galaxies at low and high redshift. It then
turns to far-field cosmological topics, exploring properties of supernovae to
z~1, strong and weak lensing, the large-scale distribution of galaxies and
baryon oscillations, and how these different probes may be combined to
constrain cosmological models and the physics of dark energy.Comment: 596 pages. Also available at full resolution at
http://www.lsst.org/lsst/sciboo
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Prevalence of Potentially Inappropriate Medication use in older drivers
Background
Potentially Inappropriate Medication (PIM) use has been studied in a variety of older adult populations across the world. We sought to examine the prevalence and correlates of PIM use in older drivers.
Methods
We applied the American Geriatrics Society 2015 Beers Criteria to baseline data collected from the “brown-bag” review of medications for participants of the Longitudinal Research on Aging Drivers (LongROAD) study to examine the prevalence and correlates of PIM use in a geographically diverse, community-dwelling sample of older drivers (n = 2949). Proportions of participants who used one or more PIMs according to the American Geriatrics Society 2015 Beers Criteria, and estimated odds ratios (ORs) and 95% confidence intervals (CIs) of PIM use associated with participant characteristics were calculated.
Results
Overall, 18.5% of the older drivers studied used one or more PIM. The most commonly used therapeutic category of PIM was benzodiazepines (accounting for 16.6% of the total PIMs identified), followed by nonbenzodiazepine hypnotics (15.2%), antidepressants (15.2%), and first-generation antihistamines (10.5%). Compared to older drivers on four or fewer medications, the adjusted ORs of PIM use were 2.43 (95% CI 1.68–3.51) for those on 5–7 medications, 4.19 (95% CI 2.95–5.93) for those on 8–11 medications, and 8.01 (95% CI 5.71–11.23) for those on ≥12 medications. Older drivers who were female, white, or living in urban areas were at significantly heightened risk of PIM use.
Conclusion
About one in five older drivers uses PIMs. Commonly used PIMs are medications known to impair driving ability and increase crash risk. Implementation of evidence-based interventions to reduce PIM use in older drivers may confer both health and safety benefits.
Trial registration
Not applicable
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Prevalence of Potentially Inappropriate Medication use in older drivers
Abstract
Background
Potentially Inappropriate Medication (PIM) use has been studied in a variety of older adult populations across the world. We sought to examine the prevalence and correlates of PIM use in older drivers.
Methods
We applied the American Geriatrics Society 2015 Beers Criteria to baseline data collected from the “brown-bag” review of medications for participants of the Longitudinal Research on Aging Drivers (LongROAD) study to examine the prevalence and correlates of PIM use in a geographically diverse, community-dwelling sample of older drivers (n = 2949). Proportions of participants who used one or more PIMs according to the American Geriatrics Society 2015 Beers Criteria, and estimated odds ratios (ORs) and 95% confidence intervals (CIs) of PIM use associated with participant characteristics were calculated.
Results
Overall, 18.5% of the older drivers studied used one or more PIM. The most commonly used therapeutic category of PIM was benzodiazepines (accounting for 16.6% of the total PIMs identified), followed by nonbenzodiazepine hypnotics (15.2%), antidepressants (15.2%), and first-generation antihistamines (10.5%). Compared to older drivers on four or fewer medications, the adjusted ORs of PIM use were 2.43 (95% CI 1.68–3.51) for those on 5–7 medications, 4.19 (95% CI 2.95–5.93) for those on 8–11 medications, and 8.01 (95% CI 5.71–11.23) for those on ≥12 medications. Older drivers who were female, white, or living in urban areas were at significantly heightened risk of PIM use.
Conclusion
About one in five older drivers uses PIMs. Commonly used PIMs are medications known to impair driving ability and increase crash risk. Implementation of evidence-based interventions to reduce PIM use in older drivers may confer both health and safety benefits.
Trial registration
Not applicable.https://deepblue.lib.umich.edu/bitstream/2027.42/152209/1/12877_2019_Article_1287.pd
ProsCan for Couples: Randomised controlled trial of a couples-based sexuality intervention for men with localised prostate cancer who receive radical prostatectomy
Background: Prostate cancer is the most common male cancer in the Western world. The most substantial long term morbidity from this cancer is sexual dysfunction with consequent adverse changes in couple and intimate relationships. Research to date has not identified an effective way to improve sexual and psychosocial adjustment for both men with prostate cancer and their partners. As well, the efficacy and cost effectiveness of peer counselling as opposed to professional models of service delivery has not yet been empirically tested. This paper presents the design of a three arm randomised controlled trial (peer vs. nurse counselling vs. usual care) that will evaluate the efficacy of two couples-based sexuality interventions (ProsCan for Couples: Peer support vs. nurse counselling) on men's and women's sexual and psychosocial adjustment after surgical treatment for localised prostate cancer; in addition to cost-effectiveness. Methods/design: Seventy couples per condition (210 couples in total) will be recruited after diagnosis and before treatment through urology private practices and hospital outpatient clinics and randomised to (1) usual care; (2) eight sessions of peer-delivered telephone support with DVD education; and (3) eight sessions of oncology nurse-delivered telephone counselling with DVD education. Two intervention sessions will be delivered before surgery and six over the six months post-surgery. The intervention will utilise a cognitive behavioural approach along with couple relationship education focussed on relationship enhancement and helping the couple to conjointly manage the stresses of cancer diagnosis and treatment. Participants will be assessed at baseline (before surgery) and 3, 6 and 12 months post-surgery. Outcome measures include: Sexual adjustment; unmet sexuality supportive care needs; attitudes to sexual help seeking; psychological adjustment; benefit finding and quality of life. Discussion: The study will provide recommendations about the efficacy of peer support vs. nurse counselling to facilitate better sexual and couple adjustment after prostate cancer as well as recommendations on whether the interventions represent efficient health service delivery
Active Zone Protein Bassoon Co-Localizes with Presynaptic Calcium Channel, Modifies Channel Function, and Recovers from Aging Related Loss by Exercise
The P/Q-type voltage-dependent calcium channels (VDCCs) are essential for synaptic transmission at adult mammalian neuromuscular junctions (NMJs); however, the subsynaptic location of VDCCs relative to active zones in rodent NMJs, and the functional modification of VDCCs by the interaction with active zone protein Bassoon remain unknown. Here, we show that P/Q-type VDCCs distribute in a punctate pattern within the NMJ presynaptic terminals and align in three dimensions with Bassoon. This distribution pattern of P/Q-type VDCCs and Bassoon in NMJs is consistent with our previous study demonstrating the binding of VDCCs and Bassoon. In addition, we now show that the interaction between P/Q-type VDCCs and Bassoon significantly suppressed the inactivation property of P/Q-type VDCCs, suggesting that the Ca2+ influx may be augmented by Bassoon for efficient synaptic transmission at NMJs. However, presynaptic Bassoon level was significantly attenuated in aged rat NMJs, which suggests an attenuation of VDCC function due to a lack of this interaction between VDCC and Bassoon. Importantly, the decreased Bassoon level in aged NMJs was ameliorated by isometric strength training of muscles for two months. The training increased Bassoon immunoreactivity in NMJs without affecting synapse size. These results demonstrated that the P/Q-type VDCCs preferentially accumulate at NMJ active zones and play essential role in synaptic transmission in conjunction with the active zone protein Bassoon. This molecular mechanism becomes impaired by aging, which suggests altered synaptic function in aged NMJs. However, Bassoon level in aged NMJs can be improved by muscle exercise
Development of Risk Prediction Equations for Incident Chronic Kidney Disease
IMPORTANCE ‐ Early identification of individuals at elevated risk of developing chronic kidney disease
could improve clinical care through enhanced surveillance and better management of underlying health
conditions.
OBJECTIVE – To develop assessment tools to identify individuals at increased risk of chronic kidney
disease, defined by reduced estimated glomerular filtration rate (eGFR).
DESIGN, SETTING, AND PARTICIPANTS – Individual level data analysis of 34 multinational cohorts from
the CKD Prognosis Consortium including 5,222,711 individuals from 28 countries. Data were collected from April, 1970 through January, 2017. A two‐stage analysis was performed, with each study first
analyzed individually and summarized overall using a weighted average. Since clinical variables were often differentially available by diabetes status, models were developed separately within participants
with diabetes and without diabetes. Discrimination and calibration were also tested in 9 external
cohorts (N=2,253,540).
EXPOSURE Demographic and clinical factors.
MAIN OUTCOMES AND MEASURES – Incident eGFR <60 ml/min/1.73 m2.
RESULTS – In 4,441,084 participants without diabetes (mean age, 54 years, 38% female), there were
660,856 incident cases of reduced eGFR during a mean follow‐up of 4.2 years. In 781,627 participants
with diabetes (mean age, 62 years, 13% female), there were 313,646 incident cases during a mean
follow‐up of 3.9 years. Equations for the 5‐year risk of reduced eGFR included age, sex, ethnicity, eGFR,
history of cardiovascular disease, ever smoker, hypertension, BMI, and albuminuria. For participants
with diabetes, the models also included diabetes medications, hemoglobin A1c, and the interaction
between the two. The risk equations had a median C statistic for the 5‐year predicted probability of
0.845 (25th – 75th percentile, 0.789‐0.890) in the cohorts without diabetes and 0.801 (25th – 75th
percentile, 0.750‐0.819) in the cohorts with diabetes. Calibration analysis showed that 9 out of 13 (69%)
study populations had a slope of observed to predicted risk between 0.80 and 1.25. Discrimination was
similar in 18 study populations in 9 external validation cohorts; calibration showed that 16 out of 18
(89%) had a slope of observed to predicted risk between 0.80 and 1.25.
CONCLUSIONS AND RELEVANCE – Equations for predicting risk of incident chronic kidney disease
developed in over 5 million people from 34 multinational cohorts demonstrated high discrimination and
variable calibration in diverse populations
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