37 research outputs found
Resource Heterogeneity Moderates the Biodiversity-Function Relationship in Real World Ecosystems
Numerous recent studies have tested the effects of plant, pollinator, and predator diversity on primary productivity, pollination, and consumption, respectively. Many have shown a positive relationship, particularly in controlled experiments, but variability in results has emphasized the context-dependency of these relationships. Complementary resource use may lead to a positive relationship between diversity and these processes, but only when a diverse array of niches is available to be partitioned among species. Therefore, the slope of the diversity-function relationship may change across differing levels of heterogeneity, but empirical evaluations of this pattern are lacking. Here we examine three important functions/properties in different real world (i.e., nonexperimental) ecosystems: plant biomass in German grasslands, parasitism rates across five habitat types in coastal Ecuador, and coffee pollination in agroforestry systems in Indonesia. We use general linear and structural equation modeling to demonstrate that the effect of diversity on these processes is context dependent, such that the slope of this relationship increases in environments where limiting resources (soil nutrients, host insects, and coffee flowers, respectively) are spatially heterogeneous. These real world patterns, combined with previous experiments, suggest that biodiversity may have its greatest impact on the functioning of diverse, naturally heterogeneous ecosystems
Tumor-associated Endo180 requires stromal-derived LOX to promote metastatic prostate cancer cell migration on human ECM surfaces
Magnetic resonance imaging (MRI) contrast agents for tumor diagnosis
10.1260/2040-2295.4.1.23Journal of Healthcare Engineering4123-4
Endo180 modulation by bisphosphonates and diagnostic accuracy in metastatic breast cancer
We thank the patients who participated in this study; Professor Gerry Thomas and the Imperial College Healthcare NHS Trust, Human Biomaterials Resource Centre (Tissue Bank); Professor Clare M Isacke (Institute of Cancer Research, London) for Endo180 antibodies; Dr Richard Harvey (Department of Medical Oncology, Imperial College Healthcare NHS Trust) for CA 15-3 antigen measurement. The Division of Cancer at Imperial College London, Imperial College Healthcare NHS Trust is an Experimental Cancer Medicine Centre (ECMC) supported by funds from Cancer Research UK and the Department of Health (C37/A7283) and forms part of Imperial Cancer Research UK Centre (C42671/A12196). CP is recipient of a CRUK Clinician Scientist award. JW is The Flow Foundation Professor of Oncology at Imperial College London. MPC and GK were supported by donations from Tony and Rita Gallagher and Imperial College NHS Healthcare Trust Special Trustees (to JW and JS). MPC was funded by The Rosetrees Trust (Grant JS16/M59; to JW and JS). A-VF was funded by Fundação para a CiĂȘncia e Tecnologia fellowship (project supervisor: JS) and Imperial College NHS Healthcare Special Trustees (to JW and JS). MR-T was funded by the Association of International Cancer Research (Grant 08-0803 to JS)
Multi-messenger observations of a binary neutron star merger
On 2017 August 17 a binary neutron star coalescence candidate (later designated GW170817) with merger time 12:41:04 UTC was observed through gravitational waves by the Advanced LIGO and Advanced Virgo detectors. The Fermi Gamma-ray Burst Monitor independently detected a gamma-ray burst (GRB 170817A) with a time delay of ~1.7 s with respect to the merger time. From the gravitational-wave signal, the source was initially localized to a sky region of 31 deg2 at a luminosity distance of 40+8-8 Mpc and with component masses consistent with neutron stars. The component masses were later measured to be in the range 0.86 to 2.26 Mo. An extensive observing campaign was launched across the electromagnetic spectrum leading to the discovery of a bright optical transient (SSS17a, now with the IAU identification of AT 2017gfo) in NGC 4993 (at ~40 Mpc) less than 11 hours after the merger by the One- Meter, Two Hemisphere (1M2H) team using the 1 m Swope Telescope. The optical transient was independently detected by multiple teams within an hour. Subsequent observations targeted the object and its environment. Early ultraviolet observations revealed a blue transient that faded within 48 hours. Optical and infrared observations showed a redward evolution over ~10 days. Following early non-detections, X-ray and radio emission were discovered at the transientâs position ~9 and ~16 days, respectively, after the merger. Both the X-ray and radio emission likely arise from a physical process that is distinct from the one that generates the UV/optical/near-infrared emission. No ultra-high-energy gamma-rays and no neutrino candidates consistent with the source were found in follow-up searches. These observations support the hypothesis that GW170817 was produced by the merger of two neutron stars in NGC4993 followed by a short gamma-ray burst (GRB 170817A) and a kilonova/macronova powered by the radioactive decay of r-process nuclei synthesized in the ejecta
BIOFRAG - a new database for analyzing BIOdiversity responses to forest FRAGmentation
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BIOFRAG â a new database for analyzing BIOdiversity responses to forest FRAGmentation
Habitat fragmentation studies have produced complex results that are challenging
to synthesize. Inconsistencies among studies may result from variation in
the choice of landscape metrics and response variables, which is often compounded
by a lack of key statistical or methodological information. Collating
primary datasets on biodiversity responses to fragmentation in a consistent and
flexible database permits simple data retrieval for subsequent analyses. We present
a relational database that links such field data to taxonomic nomenclature,
spatial and temporal plot attributes, and environmental characteristics. Field
assessments include measurements of the response(s) (e.g., presence, abundance,
ground cover) of one or more species linked to plots in fragments
within a partially forested landscape. The database currently holds 9830 unique
species recorded in plots of 58 unique landscapes in six of eight realms: mammals
315, birds 1286, herptiles 460, insects 4521, spiders 204, other arthropods
85, gastropods 70, annelids 8, platyhelminthes 4, Onychophora 2, vascular
plants 2112, nonvascular plants and lichens 320, and fungi 449. Three landscapes
were sampled as long-term time series (>10 years). Seven hundred and
eleven species are found in two or more landscapes. Consolidating the substantial
amount of primary data available on biodiversity responses to fragmentation
in the context of land-use change and natural disturbances is an essential
part of understanding the effects of increasing anthropogenic pressures on land.
The consistent format of this database facilitates testing of generalizations concerning
biologic responses to fragmentation across diverse systems and taxa. It
also allows the re-examination of existing datasets with alternative landscape
metrics and robust statistical methods, for example, helping to address pseudo-replication
problems. The database can thus help researchers in producing
broad syntheses of the effects of land use. The database is dynamic and inclusive,
and contributions from individual and large-scale data-collection efforts
are welcome.Keywords: Species turnover,
Data sharing,
Database,
Global change,
Landscape metrics,
Edge effects,
Forest fragmentation,
Matrix contrast,
Bioinformatic
J-PLUS: The Javalambre Photometric Local Universe Survey
The Javalambre Photometric Local Universe Survey (J-PLUS) is an ongoing 12-band photometric optical survey, observing thousands of square degrees of the Northern Hemisphere from the dedicated JAST/T80 telescope at the Observatorio Astrofisico de Javalambre (OAJ). The T80Cam is a camera with a field of view of 2 deg(2) mounted on a telescope with a diameter of 83 cm, and is equipped with a unique system of filters spanning the entire optical range (3500-10 000 angstrom). This filter system is a combination of broad-, medium-, and narrow-band filters, optimally designed to extract the rest-frame spectral features (the 3700-4000 angstrom Balmer break region, H delta, Ca H+K, the G band, and the Mg b and Ca triplets) that are key to characterizing stellar types and delivering a low-resolution photospectrum for each pixel of the observed sky. With a typical depth of AB similar to 21.25 mag per band, this filter set thus allows for an unbiased and accurate characterization of the stellar population in our Galaxy, it provides an unprecedented 2D photospectral information for all resolved galaxies in the local Universe, as well as accurate photo-z estimates (at the delta z/(1 + z) similar to 0.005-0.03 precision level) for moderately bright (up to r similar to 20 mag) extragalactic sources. While some narrow-band filters are designed for the study of particular emission features ([O II]/lambda 3727, H alpha/lambda 6563) up to z < 0.017, they also provide well-defined windows for the analysis of other emission lines at higher redshifts. As a result, J-PLUS has the potential to contribute to a wide range of fields in Astrophysics, both in the nearby Universe (Milky Way structure, globular clusters, 2D IFU-like studies, stellar populations of nearby and moderate-redshift galaxies, clusters of galaxies) and at high redshifts (emission-line galaxies at z approximate to 0.77, 2.2, and 4.4, quasi-stellar objects, etc.). With this paper, we release the first similar to 1000 deg(2) of J-PLUS data, containing about 4.3 million stars and 3.0 million galaxies at r < 21 mag. With a goal of 8500 deg(2) for the total J-PLUS footprint, these numbers are expected to rise to about 35 million stars and 24 million galaxies by the end of the survey