5,550 research outputs found
Red-sequence galaxies with young stars and dust: The cluster Abell 901/902 seen with COMBO-17
We report the discovery of a rich component of dusty star-forming galaxies
contaminating the red-sequence in the supercluster system comprising Abell
901a, 901b and A902 at redshift ~0.17. These galaxies do not fit into the
colour-density relation, because their preferred habitat is different from that
of regular red-sequence galaxies, which are typically dust-poor, old and
passively evolving. The dusty red galaxies prefer the medium-density outskirts
of clusters while being rare in both the low-density field and the high-density
cluster cores. This new result is based on the information content in the
medium-band photometry of the COMBO-17 survey. The photo-z accuracy of the ~800
brightest cluster galaxies is <0.01 and of the order of the velocity dispersion
of the cluster. This enables us to select a rich and clean cluster sample, in
which we can trace age-sensitive and dust-sensitive spectral features
independently with the detailed medium-band SED data. We find the red colour of
the dusty galaxies to be a result of dust extinction combined with relatively
old stellar ages. We speculate that the dusty red galaxies could either be a
product of minor mergers between established old red cluster galaxies with
infalling blue field galaxies, or mark a period in the internal transformation
of blue field galaxies into red cluster galaxies, which is triggered by the
environmental influences experienced during cluster infall.Comment: accepted version, only minor changes and typos corrected, 17 pages in
A&A print forma
Antibody validation of immunohistochemistry for biomarker discovery: Recommendations of a consortium of academic and pharmaceutical based histopathology researchers
As biomarker discovery takes centre-stage, the role of immunohistochemistry within that process is increasing. At the same time, the number of antibodies being produced for ‘‘research use’’ continues to rise and it is important that antibodies to be used as biomarkers are validated for specificity and sensitivity before use. This guideline seeks to provide a stepwise approach for the validation of an antibody for immunohistochemical assays, reflecting the views of a consortium of academic and pharmaceutical based histopathology researchers. We propose that antibodies are placed into a tier system, level 1–3, based on evidence of their usage in immunohistochemistry, and that the degree of validation required is proportionate to their place on that tier
Deprivation based inequality in NOx emissions in England
Inequality in air pollution exposure is an established problem globally; this study evaluates inequality in NOx emissions in England. NOx is a class of air pollutants with a detrimental impact on human health. Emissions of NOx in 2019 from the major source sectors across England were linked to deprivation data from the English Indices of Multiple Deprivation (IMD) using Lower layer Super Output Areas (LSOAs). The median NOx emissions in the most deprived decile of LSOAs was 16 tonnes per km2 per year compared with 7.0 in the least deprived. A linear regression model to account for the whole dataset showed higher inequality, with emissions of 19 tonnes per km2 per year NOx for the most deprived decile and 7.3 for the least deprived. All major emission sources, such as transport, domestic combustion, point sources and industry showed deprivation-based inequality. Geographic classifications such as region, city and Rural Urban Classification were shown to have inequalities within them, and the differences between them were shown to drive national inequality. Inequalities in the distribution of NOx emissions persisted at all levels of population density. Less densely populated, typically rural, areas had lower absolute emissions, but the highest emissions-based inequality due to point sources disproportionately affecting more deprived areas
Movement of forest-dependent dung beetles through riparian buffers in Bornean oil palm plantations
ABSTRACT Fragmentation of tropical forests is increasing globally, with negative impacts for biodiversity. In Southeast Asia, expansion of oil palm agriculture has caused widespread deforestation, forest degradation, and fragmentation. Persistence of forest-dependent species within these fragmented landscapes is likely to depend on the capacity of individuals to move between forest patches. In oil palm landscapes, riparian buffers along streams and rivers are potential movement corridors, but their use by moving animals is poorly studied. We examined how six dung beetle species traversed riparian buffers connected to a continuous forest reserve area within an oil palm plantation in Sabah, Malaysian Borneo. We used a mark-release-recapture study and a new Bayesian Joint Species Movement Modelling (JSMM) approach, extended to a continuous capture process model. Dung beetle species were fairly generalist in their habitat use, but two species showed a statistically-supported preference for riparian buffer forest over oil palm, and one species showed a strong preference for forest reserve over riparian buffer, indicating the importance of forested areas within oil palm landscapes for some species. A land-use change simulation indicated that the loss of riparian buffers in oil palm will result in reduced movement by forest-dependent species. Synthesis and applications: Our results provide evidence for the use of riparian buffers in oil palm plantations for forest-dependent dung beetle species, strengthening the case for their retention, restoration, and re-establishment. Furthermore, our study demonstrates the wider applicability of the Joint Species Movement Modelling (JSMM) framework to assess movement behaviour of species in fragmented landscapes, a vital tool for future forest and landscape management and conservation prioritisation exercises.Peer reviewe
Wound healing and hyper-hydration - a counter intuitive model
Winters seminal work in the 1960s relating to providing an optimal level of moisture to aid wound healing (granulation and re-epithelialisation) has been the single most effective advance in wound care over many decades. As such the development of advanced wound dressings that manage the fluidic wound environment have provided significant benefits in terms of healing to both patient and clinician. Although moist wound healing provides the guiding management principle confusion may arise between what is deemed to be an adequate level of tissue hydration and the risk of developing maceration. In addition, the counter-intuitive model ‘hyper-hydration’ of tissue appears to frustrate the moist wound healing approach and advocate a course of intervention whereby tissue is hydrated beyond what is a normally acceptable therapeutic level. This paper discusses tissue hydration, the cause and effect of maceration and distinguishes these from hyper-hydration of tissue. The rationale is to provide the clinician with a knowledge base that allows optimisation of treatment and outcomes and explains the reasoning behind wound healing using hyper-hydration
The new resilience of emerging and developing countries: systemic interlocking, currency swaps and geoeconomics
The vulnerability/resilience nexus that defined the interaction between advanced and developing economies in the post-WWII era is undergoing a fundamental transformation. Yet, most of the debate in the current literature is focusing on the structural constraints faced by the Emerging and Developing Countries (EDCs) and the lack of changes in the formal structures of global economic governance. This paper challenges this literature and its conclusions by focusing on the new conditions of systemic interlocking between advanced and emerging economies, and by analysing how large EDCs have built and are strengthening their economic resilience. We find that a significant redistribution of ‘policy space’ between advanced and emerging economies have taken place in the global economy. We also find that a number of seemingly technical currency swap agreements among EDCs have set in motion changes in the very structure of global trade and finance. These developments do not signify the end of EDCs’ vulnerability towards advanced economies. They signify however that the economic and geoeconomic implications of this vulnerability have changed in ways that constrain the options available to advanced economies and pose new challenges for the post-WWII economic order
Optimizing the vertebrate vestibular semicircular canal: could we balance any better?
The fluid-filled semicircular canals (SCCs) of the vestibular system are used
by all vertebrates to sense angular rotation. Despite masses spanning seven
decades, all mammalian SCCs are nearly the same size. We propose that the SCC
represents a sensory organ that evolution has `optimally designed'. Four
geometric parameters are used to characterize the SCC, and `building materials'
of given physical properties are assumed. Identifying physical and
physiological constraints on SCC operation, we find that the most sensitive SCC
has dimensions consistent with available data.Comment: 4 pages, 3 figure
Cooperative Extension Work in Aroostook County, Maine, Annual Report, December 1, 1966-November 30, 1967
Redox Properties of Mixed Methyl/Vinylferrocenyl Monolayers on Si(111) Surfaces
We report the redox properties of Si(111) surfaces functionalized with a mixed monolayer of vinylferrocenyl and methyl moieties that have been characterized using spectroscopic, electrical, and electrochemical techniques. The silicon was functionalized using reaction conditions analogous to those of hydrosilylation, but instead of a H-terminated Si surface, a chlorine-terminated Si precursor surface was used to produce the linked vinyl-modified functional group. The functionalized surfaces were characterized by time-resolved photoconductivity decay, X-ray photoelectron spectroscopy, electrochemical measurements, and photoelectrochemical measurements. The functionalized Si surface was well passivated, exhibited high surface coverage and few remaining reactive Si atop sites, had a very low surface recombination velocity, and displayed little initial surface oxidation. The surface was stable toward atmospheric and electrochemical oxidation. The surface coverage of vinylferrocene (or fluorostyrene) was controllably varied from 0 up to 30% of a monolayer. Interfacial charge transfer to the attached ferrocene group was relatively rapid, and a photovoltage of 0.4 V was generated upon illumination of functionalized n-type silicon surfaces in CH_(3)CN
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