1,030 research outputs found
A reply to âRanging Behavior Drives Parasite Richness: A More Parsimonious Hypothesisâ
This preprint has been reviewed and recommended by Peer Community In Ecology (https://dx.doi.org/10.24072/pci.ecology.100001).
In a recent article, Bicca-Marques and Calegaro-Marques [Bicca-Marques JC, Calegaro-Marques C (2016) Ranging behavior drives parasite richness: A more parsimonious hypothesis. American Journal of Primatology 78: 923â927.] discussed the putative assumptions related to an interpretation we provided regarding an observed positive relationship between weekly averaged parasite richness of a group of mandrills (Mandrillus sphinx) and their daily path lengths (DPL), published earlier in the same journal [Brockmeyer T, Kappeler PM, Willaume E, Benoit L, Mboumba S, Charpentier MJE (2015) Social organization and space use of a wild mandrill (Mandrillus sphinx) group. American Journal of Primatology 77: 1036â1048.]. In our article, we proposed, inter alia, that âthe daily travels of mandrills could be seen as a way to escape contaminated habitats on a local scaleâ. In their article, Bicca-Marques and Calegaro-Marques proposed an alternative mechanism that they considered to be more parsimonious. In their view, increased DPL also increases exposure to novel parasites from the environment. In other words, while we proposed that elevated DPL may be a consequence of elevated parasite richness, they viewed it as a cause. We are happy to see that our study attracted so much interest that it evoked a public comment. We are also grateful to Bicca-Marques and Calegaro-Marques for pointing out an obvious alternative scenario that we failed to discuss and for laying out several key factors and assumptions that should be addressed by future studies examining the links between parasite risk and group ranging. We use this opportunity to advance this discourse by responding to some of the criticisms raised in their discussion of our article. In this reply, we briefly contextualize the main object of criticism. We then discuss the putative parsimony of the two competing scenarios
Distorted Copulas: Constructions and Tail Dependence
Given a copula C, we examine under which conditions on an order isomorphism Ï of [0, 1] the distortion C Ï: [0, 1]2 â [0, 1], C Ï(x, y) = Ï{C[Ïâ1(x), Ïâ1(y)]} is again a copula. In particular, when the copula C is totally positive of order 2, we give a sufficient condition on Ï that ensures that any distortion of C by means of Ï is again a copula. The presented results allow us to introduce in a more flexible way families of copulas exhibiting different behavior in the tails
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Potential Therapeutic Competition in Community-Living Older Adults in the U.S.: Use of Medications That May Adversely Affect a Coexisting Condition
OBJECTIVE: The 75% of older adults with multiple chronic conditions are at risk of therapeutic competition (i.e. treatment for
one condition may adversely affect a coexisting condition). The objective was to determine the prevalence of potential
therapeutic competition in community-living older adults.
METHODS: Cross-sectional descriptive study of a representative sample of 5,815 community-living adults 65 and older in the
U.S, enrolled 2007â2009. The 14 most common chronic conditions treated with at least one medication were ascertained
from Medicare claims. Medication classes recommended in national disease guidelines for these conditions and used by
â„2% of participants were identified from in-person interviews conducted 2008â2010. Criteria for potential therapeutic
competition included: 1) well-acknowledged adverse medication effect; 2) mention in disease guidelines; or 3) report in a
systematic review or two studies published since 2000. Outcomes included prevalence of situations of potential therapeutic
competition and frequency of use of the medication in individuals with and without the competing condition.
RESULTS: Of 27 medication classes, 15 (55.5%) recommended for one study condition may adversely affect other study
conditions. Among 91 possible pairs of study chronic conditions, 25 (27.5%) have at least one potential therapeutic
competition. Among participants, 1,313 (22.6%) received at least one medication that may worsen a coexisting condition;
753 (13%) had multiple pairs of such competing conditions. For example, among 846 participants with hypertension and
COPD, 16.2% used a nonselective beta-blocker. In only 6 of 37 cases (16.2%) of potential therapeutic competition were
those with the competing condition less likely to receive the medication than those without the competing condition.
CONCLUSIONS: One fifth of older Americans receive medications that may adversely affect coexisting conditions. Determining
clinical outcomes in these situations is a research and clinical priority. Effects on coexisting conditions should be considered
when prescribing medications.This is the publisherâs final pdf. The published article is copyrighted by the author(s) and published by the Public Library of Science. The published article can be found at: https://doi.org/10.1371/journal.pone.008944
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Higher groundwater levels in western Europe characterize warm periods in the Common Era.
Funder: Projekt DEALHydroclimate, the interplay of moisture supply and evaporative demand, is essential for ecological and agricultural systems. The understanding of long-term hydroclimate changes is, however, limited because instrumental measurements are inadequate in length to capture the full range of precipitation and temperature variability and by the uneven distribution of high-resolution proxy records in space and time. Here, we present a tree-ring-based reconstruction of interannual to centennial-scale groundwater level (GWL) fluctuations for south-western Germany and north-eastern France. Continuously covering the period of 265-2017 CE, our new record from the Upper Rhine Valley shows that the warm periods during late Roman, medieval and recent times were characterized by higher GWLs. Lower GWLs were found during the cold periods of the Late Antique Little Ice Age (LALIA; 536 toâ~â660 CE) and the Little Ice Age (LIA; between medieval and recent warming). The reconstructed GWL fluctuations are in agreement with multidecadal North Atlantic climate variability derived from independent proxies. Warm and wet hydroclimate conditions are found during warm states of the Atlantic Ocean and positive phases of the North Atlantic Oscillation on decadal scales
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Genome-wide trans-ancestry meta-analysis provides insight into the genetic architecture of type 2 diabetes susceptibility.
To further understanding of the genetic basis of type 2 diabetes (T2D) susceptibility, we aggregated published meta-analyses of genome-wide association studies (GWAS), including 26,488 cases and 83,964 controls of European, east Asian, south Asian and Mexican and Mexican American ancestry. We observed a significant excess in the directional consistency of T2D risk alleles across ancestry groups, even at SNPs demonstrating only weak evidence of association. By following up the strongest signals of association from the trans-ethnic meta-analysis in an additional 21,491 cases and 55,647 controls of European ancestry, we identified seven new T2D susceptibility loci. Furthermore, we observed considerable improvements in the fine-mapping resolution of common variant association signals at several T2D susceptibility loci. These observations highlight the benefits of trans-ethnic GWAS for the discovery and characterization of complex trait loci and emphasize an exciting opportunity to extend insight into the genetic architecture and pathogenesis of human diseases across populations of diverse ancestry
Optimizing Retention in a Pragmatic Trial of CommunityâLiving Older Persons: The STRIDE Study
Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/155912/1/jgs16356.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/155912/2/jgs16356_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/155912/3/jgs16356-sup-0001-supinfo.pd
New genetic loci implicated in fasting glucose homeostasis and their impact on type 2 diabetes risk.
Levels of circulating glucose are tightly regulated. To identify new loci influencing glycemic traits, we performed meta-analyses of 21 genome-wide association studies informative for fasting glucose, fasting insulin and indices of beta-cell function (HOMA-B) and insulin resistance (HOMA-IR) in up to 46,186 nondiabetic participants. Follow-up of 25 loci in up to 76,558 additional subjects identified 16 loci associated with fasting glucose and HOMA-B and two loci associated with fasting insulin and HOMA-IR. These include nine loci newly associated with fasting glucose (in or near ADCY5, MADD, ADRA2A, CRY2, FADS1, GLIS3, SLC2A2, PROX1 and C2CD4B) and one influencing fasting insulin and HOMA-IR (near IGF1). We also demonstrated association of ADCY5, PROX1, GCK, GCKR and DGKB-TMEM195 with type 2 diabetes. Within these loci, likely biological candidate genes influence signal transduction, cell proliferation, development, glucose-sensing and circadian regulation. Our results demonstrate that genetic studies of glycemic traits can identify type 2 diabetes risk loci, as well as loci containing gene variants that are associated with a modest elevation in glucose levels but are not associated with overt diabetes
A Randomized Trial of a Physical Conditioning Program to Enhance the Driving Performance of Older Persons
BACKGROUND: As the number of older drivers increases, concern has been raised about the potential safety implications. Flexibility, coordination, and speed of movement have been associated with older driversâ on road performance. OBJECTIVE: To determine whether a multicomponent physical conditioning program targeted to axial and extremity flexibility, coordination, and speed of movement could improve driving performance among older drivers. DESIGN: Randomized controlled trial with blinded assignment and end point assessment. Participants randomized to intervention underwent graduated exercises; controls received home, environment safety modules. PARTICIPANTS: Drivers, 178, ageââ„â70Â years with physical, but without substantial visual (acuity 20/40 or better) or cognitive (Mini Mental State Examination score â„24) impairments were recruited from clinics and community sources. MEASUREMENTS: On-road driving performance assessed by experienced evaluators in dual-brake equipped vehicle in urban, residential, and highway traffic. Performance rated three ways: (1) 36-item scale evaluating driving maneuvers and traffic situations; (2) evaluatorâs overall rating; and (3) critical errors committed. Driving performance reassessed at 3Â months by evaluator blinded to treatment group. RESULTS: Least squares mean change in road test scores at 3Â months compared to baseline was 2.43 points higher in intervention than control participants (Pâ=â.03). Intervention drivers committed 37% fewer critical errors (Pâ=â.08); there were no significant differences in evaluatorâs overall ratings (Pâ=â.29). No injuries were reported, and complaints of pain were rare. CONCLUSIONS: This safe, well-tolerated intervention maintained driving performance, while controls declined during the study period. Having interventions that can maintain or enhance driving performance may allow clinicianâpatient discussions about driving to adopt a more positive tone, rather than focusing on driving limitation or cessation
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