2,984 research outputs found
Aquatic Invasive Species Change Ecosystem Services from the World\u27s Largest Wild Sockeye Salmon Fisheries in Alaska
This study combines a multi-method approach to structured expert judgment with market valuation to forecast fisheries damages from introduced invasive species. The method is applied to a case study of Alaska’s first submersed aquatic invasive plant, Elodea spp., threatening Alaska’s salmon fisheries. Assuming that Elodea spp. remains unmanaged, estimated mean damages to commercial sockeye fisheries aggregated across Alaska amount to a potential 577 million annually (5.1 billion cumulatively over the next 100 years reaching $400 million after 10 years. Results from the expert elicitation indicate that there is a 35% chance of positive net benefits associated with the believed positive effects of Elodea spp. on sockeye salmon (Oncorhynchus nerka). Despite the potential for positive net gains, the magnitude of the most probable damage estimate may justify substantial investment in keeping productive freshwater systems free of aquatic invasive species. The damage estimate for Alaska is significantly larger than similar estimates in the Great Lakes where ecosystems are already impaired by multiple aquatic invasive species, underscoring the value of keeping functioning ecosystems with global market value productive. This study is the first to estimate ecosystem service loss associated with introduction of an aquatic invasive species to freshwater habitat that supports the world’s most valuable wild sockeye salmon fisheries. Important policy implications related to natural resource management and efficient allocation of scarce resources are discusse
Anesthesia for thoracic surgery in infants and children
The management of infants and children presenting for thoracic surgery poses a variety of challenges for anesthesiologists. A thorough understanding of the implications of developmental changes in cardiopulmonary anatomy and physiology, associated comorbid conditions, and the proposed surgical intervention is essential in order to provide safe and effective clinical care. This narrative review discusses the perioperative anesthetic management of pediatric patients undergoing noncardiac thoracic surgery, beginning with the preoperative assessment. The considerations for the implementation and management of one-lung ventilation (OLV) will be reviewed, and as will the anesthetic implications of different surgical procedures including bronchoscopy, mediastinoscopy, thoracotomy, and thoracoscopy. We will also discuss pediatric-specific disease processes presenting in neonates, infants, and children, with an emphasis on those with unique impact on anesthetic management
Probing hyperbolic polaritons using infrared attenuated total reflectance micro-spectroscopy
Hyperbolic polariton modes are highly appealing for a broad range of
applications in nanophotonics, including surfaced enhanced sensing,
sub-diffractional imaging and reconfigurable metasurfaces. Here we show that
attenuated total reflectance micro-spectroscopy (ATR) using standard
spectroscopic tools can launch hyperbolic polaritons in a Kretschmann-Raether
configuration. We measure multiple hyperbolic and dielectric modes within the
naturally hyperbolic material hexagonal boron nitride as a function of
different isotopic enrichments and flake thickness. This overcomes the
technical challenges of measurement approaches based on nanostructuring, or
scattering scanning nearfield optical microscopy. Ultimately, our ATR approach
allows us to compare the optical properties of small-scale materials prepared
by different techniques systematicallyComment: 13 pages 4 figure
White-matter abnormalities in brain during early abstinence from methamphetamine abuse
Previous studies revealed microstructural abnormalities in prefrontal white matter and corpus callosum of long-term abstinent chronic methamphetamine abusers. In view of the importance of the early abstinence period in treatment retention, we compared 23 methamphetamine-dependent subjects abstinent from methamphetamine for 7–13 days with 18 healthy comparison subjects. As certain metabolic changes in the brain first manifest after early abstinence from methamphetamine, it is also possible that microstructural white-matter abnormalities are not yet present during early abstinence.
Using diffusion tensor imaging at 1.5 T, fractional anisotropy (FA) was measured in prefrontal white matter at four inferior–superior levels parallel to the anterior commissure–posterior commissure (AC–PC) plane. We also sampled FA in the corpus callosum at the midline and at eight bilateral, fiber-tract sites in other regions implicated in effects of methamphetamine.
The methamphetamine group exhibited lower FA in right prefrontal white matter above the AC–PC plane (11.9% lower; p = 0.007), in midline genu corpus callosum (3.9%; p = 0.019), in left and right midcaudal superior corona radiata (11.0% in both hemispheres, p’s = 0.020 and 0.016, respectively), and in right perforant fibers (7.3%; p = 0.025). FA in left midcaudal superior corona radiata was correlated with depressive and generalized psychiatric symptoms within the methamphetamine group.
The findings support the idea that methamphetamine abuse produces microstructural abnormalities in white matter underlying and interconnecting prefrontal cortices and hippocampal formation. These effects are already present during the first weeks of abstinence from methamphetamine and are linked to psychiatric symptoms assessed during this period
Global adoption of single-shot targeted intraoperative radiotherapy (TARGIT-IORT) for breast cancer – better for patients, better for health care systems
Introduction: TARGeted Intraoperative radioTherapy (TARGIT-IORT), developed in the late 1990s,
delivers radiotherapy targeted to the fresh tumour bed exposed immediately after lumpectomy for breast
cancer. Long-term results of the TARGIT-A trial found TARGIT-IORT during lumpectomy to be as
effective as whole breast radiotherapy, and led to significantly fewer deaths from non-breast cancer causes.
This paper documents its worldwide impact and provides interactive tools for clinicians and patients. /
Method: Each centre provided the number of patients treated using TARGIT-IORT. These data were
plotted on an interactive ‘My Google Map’. We also created an interactive web-based tool. Using the longterm outcomes from the TARGIT-A trial, we estimated the total savings in travel miles, time, carbon
footprint, and the number of deaths from other causes that might be prevented. /
Results: Data from 242 (93%) of the 260 centres treating patients from 35 countries were available. The
first was treated in 1998 at University College London. As of early 2020, at least 44752 women with breast
cancer have been treated with TARGIT-IORT. https://targit.org.uk/travel displays the Google-map of
centres with number of cases and the interactive tool that enables patients to find the nearest centre offering
TARGIT-IORT and their travel savings. Scaling the main benefits up to the already treated patients, >20
million miles of travel would have been saved, and about 2000 deaths prevented. /
Discussion: One can ascertain the number of patients treated with a novel treatment. These data show how
widely TARGIT-IORT has now been adopted and gives an indication of its beneficial worldwide impact
on a large number of women with breast cancer
Environmentally and behaviourally mediated co-occurrence of functional traits in bird communities of tropical forest fragments
Two major theories of community assembly - based on the assumption of limiting similarity' or 'habitat filtering', respectively - predict contrasting patterns in the spatial arrangement of functional traits. Previous analyses have made progress in testing these predictions and identifying underlying processes, but have also pointed to theoretical as well as methodological shortcomings. Here we applied a recently developed methodology for spatially explicit analysis of phylogenetic meta-community structure to study the pattern of co-occurrence of functional traits in Afrotropical and Neotropical bird species inhabiting forest fragments. Focusing separately on locomotory, dietary, and dispersal traits, we tested whether environmental filtering causes spatial clustering, or competition leads to spatial segregation as predicted by limiting similarity theory. We detected significant segregation of species co-occurrences in African fragments, but not in the Neotropical ones. Interspecific competition had a higher impact on trait co-occurrence than filter effects, yet no single functional trait was able to explain the observed degree of spatial segregation among species. Despite high regional variability spanning from spatial segregation to aggregation, we found a consistent tendency for a clustered spatial patterning of functional traits among communities in fragmented landscapes, particularly in non-territorial species. Overall, we show that behavioural effects, such as territoriality, and environmental effects, such as the area of forest remnants or properties of the landscape matrix in which they are embedded, can strongly affect the pattern of trait co-occurrence. Our findings suggest that trait-based analyses of community structure should include behavioural and environmental covariates, and we here provide an appropriate method for linking functional traits, species ecology and environmental conditions to clarify the drivers underlying spatial patterns of species co-occurrence
- …