492 research outputs found
Distribution of the birds of the Philippines: biogeography and conservation priorities
The Philippine islands hold a concentration of species diversity and endemism of global
importance, yet few studies have analyzed biogeographic patterns or attempted to
prioritize areas for conservation within the archipelago. We analyzed distributions of 386
species on 28 Philippine islands and island groups, documenting intense concentration of
species richness, especially of endemic species, on the two largest islands, Mindanao and
Luzon. Factors identified as influencing species richness included island area, maximum
elevation, and Pleistocene patterns of connection and isolation. Reserve systems were
developed based on heuristic complementarity algorithms, and compared with the
existing Integrated Protected Areas (IPAS) system in the country, showing that IPAS is
an impressive first step towards protecting avian diversity in the country. Addition of
presently proposed reserves on Palawan and Mindoro would make IPAS a near-optimal
reserve design, at least at the level of island representation. Important challenges remain,
however, with regard to design of reserve systems within islands to represent complete
island avifaunas
Constitutive phosphorylation of MDC1 physically links the MRE11–RAD50–NBS1 complex to damaged chromatin
The MRE11–RAD50–Nijmegen breakage syndrome 1 (NBS1 [MRN]) complex accumulates at sites of DNA double-strand breaks (DSBs) in microscopically discernible nuclear foci. Focus formation by the MRN complex is dependent on MDC1, a large nuclear protein that directly interacts with phosphorylated H2AX. In this study, we identified a region in MDC1 that is essential for the focal accumulation of the MRN complex at sites of DNA damage. This region contains multiple conserved acidic sequence motifs that are constitutively phosphorylated in vivo. We show that these motifs are efficiently phosphorylated by caseine kinase 2 (CK2) in vitro and directly interact with the N-terminal forkhead-associated domain of NBS1 in a phosphorylation-dependent manner. Mutation of these conserved motifs in MDC1 or depletion of CK2 by small interfering RNA disrupts the interaction between MDC1 and NBS1 and abrogates accumulation of the MRN complex at sites of DNA DSBs in vivo. Thus, our data reveal the mechanism by which MDC1 physically couples the MRN complex to damaged chromatin
Methane Mitigation:Methods to Reduce Emissions, on the Path to the Paris Agreement
The atmospheric methane burden is increasing rapidly, contrary to pathways compatible with the goals of the 2015 United Nations Framework Convention on Climate Change Paris Agreement. Urgent action is required to bring methane back to a pathway more in line with the Paris goals. Emission reduction from “tractable” (easier to mitigate) anthropogenic sources such as the fossil fuel industries and landfills is being much facilitated by technical advances in the past decade, which have radically improved our ability to locate, identify, quantify, and reduce emissions. Measures to reduce emissions from “intractable” (harder to mitigate) anthropogenic sources such as agriculture and biomass burning have received less attention and are also becoming more feasible, including removal from elevated-methane ambient air near to sources. The wider effort to use microbiological and dietary intervention to reduce emissions from cattle (and humans) is not addressed in detail in this essentially geophysical review. Though they cannot replace the need to reach “net-zero” emissions of CO2, significant reductions in the methane burden will ease the timescales needed to reach required CO2 reduction targets for any particular future temperature limit. There is no single magic bullet, but implementation of a wide array of mitigation and emission reduction strategies could substantially cut the global methane burden, at a cost that is relatively low compared to the parallel and necessary measures to reduce CO2, and thereby reduce the atmospheric methane burden back toward pathways consistent with the goals of the Paris Agreement
Illawarra Born cross-generational health study: feasibility of a multi-generational birth cohort study
Background: There is a strong interest in the concept of developmental origins of health and disease and their influence on various factors from cradle to grave . Despite the increasing appreciation of this lifelong legacy across the human life course, many gaps remain in the scientific understanding of mechanisms influencing these formative phases. Cross-generational susceptibility to health problems is emerging as a focus of research in the context of birth cohort studies. The primary aim of the Illawarra Born study is to make scientific discoveries associated with improving health and wellbeing across the lifespan, with a particular focus on preventable chronic diseases, especially mental health. This birth cohort study will follow and collect data from three cohorts representing different stages across the lifespan: infants, adults (parents) and older adults (grandparents). The multi-generational, cross-sectional and longitudinal design of this birth cohort study supports a focus on the contributions of genetics, environment and lifestyle on health and wellbeing. The feasibility of conducting a multi-generational longitudinal birth cohort project was conducted through a small pilot study.
Methods/design: The purpose of this paper is to report on the feasibility and acceptability of the research protocol for a collaborative cross-generation health study in the community and test recruitment and outcome measures for the main study. This feasibility study included pregnant women who were intending to give birth in the Illawarra-Shoalhaven region in Eastern Australia. The area includes a large, regional referral hospital, with capacity to treat specialist and complex cases. Pregnant women were asked to participate in five data collection waves beginning at 22 weeks gestation and ending with a 6-month post-partum appointment. Recruitment was then extended, via the pregnant women, to also include fathers and maternal grandmothers.
Discussion: This feasibility study focused on the perinatal period and collected data across three multi-disciplinary domains including mental health, diet, exposures to toxins and the role of these in maternal and infant outcomes. Forty-one families participated in extensive data collection from 22 weeks gestation to 6-months post-partum. Factors impacting on viability and feasibility including recruitment solutions provide the basis for a large-scale study
Peripheral Determinants of Oxygen Utilization in Heart Failure With Preserved Ejection Fraction
The aim of this study was to determine the arteriovenous oxygen content difference (ΔAVO2) in adult subjects with and without heart failure with preserved ejection fraction (HFpEF) during systemic and forearm exercise. Subjects with HFpEF had reduced ΔAVO2. Forearm diffusional conductance for oxygen, a lumped conductance parameter that incorporates all impediments to the movement of oxygen from red blood cells in skeletal muscle capillaries into the mitochondria within myocytes, was estimated. Forearm diffusional conductance for oxygen was not different among adults with HFpEF, those with hypertension, and healthy control subjects; therefore, diffusional conductance cannot explain the reduced forearm ΔAVO2. Instead, adiposity was strongly associated with ΔAVO2, suggesting an active role for adipose tissue in reducing exercise capacity in patients with HFpEF
Using Geographic Information Systems to investigate variations in accessibility to ‘extended hours’ primary healthcare provision
There are ongoing policy concerns surrounding the difficulty in obtaining timely appointments to primary healthcare services and the potential impact on, for example, attendance at accident and emergency services and potential health outcomes. Using the case study of potential access to primary healthcare services in Wales, Geographic Information System (GIS)‐based tools that permit a consideration of population‐to‐provider ratios over space are used to examine variations in geographical accessibility to general practitioner (GP) surgeries offering appointment times outside of ‘core’ operating hours. Correlation analysis is used to explore the association of accessibility scores with potential demand for such services using UK Population Census data. Unlike the situation in England, there is a tendency for accessibility to those surgeries offering ‘extended’ hours of appointment times to be better for more deprived census areas in Wales. However, accessibility to surgeries offering appointments in the evening was associated with lower levels of working age population classed as ‘economically active’; that is, those who could be targeted beneficiaries of policies geared towards ‘extended’ appointment hours provision. Such models have the potential to identify spatial mismatches of different facets of primary healthcare, such as ‘extended’ hours provision available at GP surgeries, and are worthy of further investigation, especially in relation to policies targeted at particular demographic groups
The seasonal nitrogen cycle in Wilkinson Basin, Gulf of Maine, as estimated by 1-D biological model optimization
Author Posting. © Elsevier B.V., 2009. This is the author's version of the work. It is posted here by permission of Elsevier B.V. for personal use, not for redistribution. The definitive version was published in Journal of Marine Systems 78 (2009): 77-93, doi:10.1016/j.jmarsys.2009.04.001.The objective of this study was to fit a simple ecosystem model to climatological
nitrogen cycle data in the Gulf of Maine, in order to calibrate the biological model
for use in future 3-D modelling studies. First depth-dependent monthly climatologies
of nitrate, ammonium, chlorophyll, zooplankton, detritus and primary production
data from Wilkinson Basin, Gulf of Maine, were created. A 6-box nitrogen-based
ecosystem model was objectively fitted to the data through parameter optimization.
Optimization was based on weighted least squares with model-data misfits nondi-
mensionalized by assigned uncertainties in the monthly climatological estimates.
These uncertainties were estimated as the standard deviations of the raw data from
the 6-meter and monthly bin averages. On average the model fits the monthly means
almost within their assigned uncertainties.
Several statistics are examined to assess model-data misfit. Pattern statistics such
as the correlation coefficient lack practical significance when data errors are large
relative to the signal, as in this application. Thus Taylor diagrams were not found
to be useful. The RMSE and model bias normalized by the data error were found
to be the most useful skill metrics as they indicate whether the model fits the data
within its estimated error.
The optimal simulated nitrogen cycle budgets are presented, as an estimate of the
seasonal nitrogen cycle in Wilkinson Basin, and discussed in context of the available
data.Wilkinson Basin has spring and fall phytoplankton blooms, and strong summer
stratification with a deep chlorophyll maximum near 21 m, just above the nitracline.
The mean euphotic zone depth is estimated to be 25 m, relatively constant with
season. The model estimates annual primary production as 176 g C m−2 yr−1,
annual new production as 71 g C m−2 yr−1 and sinking PON fluxes of 9.7 and 4.7
g N m−2 yr−1 at 24 and 198 m respectively.
Areas for improvement in the biological model, the model optimization method,
and significant data gaps are identified.This work was supported by ONR, NSF, and NOAA grant to Dennis
McGillicuddy
Synovial tissue signatures enhance clinical classification and prognostic/treatment response algorithms in early inflammatory arthritis and predict requirement for subsequent biological therapy: results from the pathobiology of early arthritis cohort (PEAC)
Funding for PEAC MRC: Grant code 36661. Funding Infrastructure support to EMR, Arthritis Research UK Experimental Treatment Centre: Grant code 20022
Effects of Age on Optical Coherence Tomography Measurements of Healthy Retinal Nerve Fiber Layer, Macula, and Optic Nerve Head
Purpose—To determine the effects of age on global and sectoral peripapillary retinal nerve fiber
layer (RNFL), macular thicknesses and optic nerve head (ONH) parameters in healthy subjects using
optical coherence tomography (OCT).
Design—Retrospective, cross-sectional observational study.
Participants—226 eyes from 124 healthy subjects were included.
Methods—Healthy subjects were scanned using the Fast RNFL, Fast Macula, and Fast ONH scan
patterns on a Stratus OCT. All global and sectoral RNFL and macular parameters and global ONH
parameters were modeled in terms of age using linear mixed effects models. Normalized slopes were
also calculated by dividing the slopes by the mean value of the OCT parameter for inter-parameter
comparison.
Main Outcome Measures—Slope of each OCT parameter across age.
Results—All global and sectoral RNFL thickness parameters statistically significantly decreased
with increasing age, except for the temporal quadrant and clock hours 8-10, which were not statistically different from a slope of zero. Highest absolute slopes were in the inferior and superior
quadrant RNFL and clock hour 1 (superior nasal). Normalized slopes showed similar rate in all sectors
except for the temporal clock hours (8-10). All macular thickness parameters statistically
significantly decreased with increasing age, except for the central fovea sector, which had a slight
positive slope that was not statistically significant. The nasal outer sector had the greatest absolute
slope. Normalized macular slope in the outer ring was similar to the normalized slopes in the RNFL.
Normalized inner ring had shallower slope than the outer ring with similar rate in all quadrants. Disc
area remained nearly constant across the ages, but cup area increased and rim area decreased with
age, both of which were statistically significant.
Conclusions—Global and regional changes due to the effects of age on RNFL, macula and ONH
OCT measurements should be considered when assessing eyes over time.National Institutes of Health (U.S.) (R01-EY13178-09)National Institutes of Health (U.S.) (R01-EY11289-23)National Institutes of Health (U.S.) (P30-EY008098
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