357 research outputs found
Putting Archaeology and Anthropology into Schools: A 2019 Update
Our 2012 article, “Putting Anthropology Into Schools,” argued that integrating anthropology and archaeology into K-12 schools must involve teacher preparation, state certification requirements, and in-service training. National anthropology and archaeology organizations’ decades-long push for the integration of their disciplines into schools was outlined but assessed as relatively limited compared to successful efforts in psychology, sociology, and economics. Some progress did occur, traced primarily to the National Science Foundation and other funders, alongside committed individuals with well-developed curriculum materials. Our 2019 publication includes the original article followed by an UPDATE outlining developments since 2012. Reports from the National Academies and the American Anthropological Association are discussed alongside efforts bythe Society for American Archaeology and the Archaeological Institute of America. Highlights also include initiatives to align anthropology and archaeology with national standards and global education goals; online resources for teachers and homeschooling parents; and informal, out-of-school opportunities including museum programs
Plasmonic nanoantenna design and fabrication based on evolutionary optimization
Nanoantennas for light enhance light-matter interaction at the nanoscale
making them useful in optical communication, sensing, and spectroscopy. So far
nanoantenna engineering has been largely based on rules derived from the radio
frequency domain which neglect the inertia of free metal electrons at optical
frequencies causing phenomena such as complete field penetration, ohmic losses
and plasmon resonances. Here we introduce a general and scalable evolutionary
algorithm that accounts for topological constrains of the fabrication method
and therefore yields unexpected nanoantenna designs exhibiting strong light
localization and enhancement which can directly be "printed" by focused-ion
beam milling. The fitness ranking in a hierarchy of such antennas is validated
experimentally by two-photon photoluminescence. Analysis of the best antennas'
operation principle shows that it deviates fundamentally from that of classical
radio wave-inspired designs. Our work sets the stage for a widespread
application of evolutionary optimization to a wide range of problems in nano
photonics.Comment: 3 figures; please see the supplementary information for additional
dat
HCl and ClO in activated Arctic air; first retrieved vertical profiles from TELIS submillimetre limb spectra
The first profile retrieval results of the Terahertz and submillimeter Limb Sounder (TELIS) balloon instrument are presented. The spectra are recorded during a 13-h balloon flight on 24 January 2010 from Kiruna, Sweden. The TELIS instrument was mounted on the MIPAS-B2 gondola and shared this platform with the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) and the mini- Differential Optical Absorption Spectroscopy (mini-DOAS) instruments. The flight took place within the Arctic vortex at an altitude of ≈34 km in chlorine activated air, and both active (ClO) and inactive chlorine (HCl) were measured over an altitude range of respectively ≈16–32 km and ≈10– 32 km. In this altitude range, the increase of ClO concentration levels during sunrise has been recorded with a temporal resolution of one minute. During the daytime equilibrium, a maximum ClO level of 2.1±0.3 ppbv has been observed at an altitude of 23.5 km. This equilibrium profile is validated against the ClO profile by the satellite instrument Microwave Limb Sounder (MLS) aboard EOS Aura. HCl profiles have been determined from two different isotopes – H35Cl and H37Cl – and are also validated againstMLS. The precision of all profiles is well below 0.01 ppbv and the overall accuracy is therefore governed by systematic effects. The total uncertainty of these effects is estimated to be maximal 0.3 ppbv for ClO around its peak value at 23.5 km during the daytime equilibrium, and for HCl it ranges from 0.05 to 0.4 ppbv, depending on altitude. In both cases the main uncertainty stems from a largely unknown non-linear response in the detector
Visualising text co-occurrence networks
We present a tool for automatically generating a visual summary of unstructured text data retrieved from documents, web sites or social media feeds. Unlike tools such as word clouds, we are able to visualise structures and topic relationships occurring in a document. These relationships are determined by a unique approach to co-occurrence analysis. The algorithm applies a decaying function to the distance between word pairs found in the original text such that words regularly occurring close to each other score highly, but even words occurring some distance apart will make a small contribution to the overall co-occurrence score. This is in contrast to other algorithms which simply count adjacent words or use a sliding window of fixed size. We show, with examples, how the network generated can be presented in tree or graph format. The tree format allows for the user to interact with the visualisation and expand or contract the data to a preferred level of detail. The tool is available as a web application and can be viewed using any modern web browse
ATF3 expression improves motor function in the ALS mouse model by promoting motor neuron survival and retaining muscle innervation
ALS is a fatal neurodegenerative disease characterized by a progressive loss of motor neurons and atrophy of distal axon terminals in muscle, resulting in loss of motor function. Motor end plates denervated by axonal retraction of dying motor neurons are partially reinnervated by remaining viable motor neurons; however, this axonal sprouting is insufficient to compensate for motor neuron loss. Activating transcription factor 3 (ATF3) promotes neuronal survival and axonal growth. Here, we reveal that forced expression of ATF3 in motor neurons of transgenic SOD1G93A ALS mice delays neuromuscular junction denervation by inducing axonal sprouting and enhancing motor neuron viability. Maintenance of neuromuscular junction innervation during the course of the disease in ATF3/SOD1G93A mice is associated with a substantial delay in muscle atrophy and improved motor performance. Although disease onset and mortality are delayed, disease duration is not affected. This study shows that adaptive axonal growth-promoting mechanisms can substantially improve motor function in ALS and importantly, that augmenting viability of the motor neuron soma and maintaining functional neuromuscular junction connections are both essential elements in therapy for motor neuron disease in the SOD1G93A mice. Accordingly, effective protection of optimal motor neuron function requires restitution of multiple dysregulated cellular pathways.link_to_OA_fulltex
The Impact of Language Barriers on Documentation of Informed Consent at a Hospital with On-Site Interpreter Services
Discrete element modelling of scaled railway ballast under triaxial conditions
The aim of this study is to demonstrate the use of tetrahedral clumps to model scaled railway ballast using the discrete element method (DEM). In experimental triaxial tests, the peak friction angles for scaled ballast are less sensitive to the confining pressure when compared to full-sized ballast. This is presumed to be due to the size effect on particle strength, whereby smaller particles are statistically stronger and exhibit less abrasion. To investigate this in DEM, the ballast is modelled using clumps with breakable asperities to produce the correct volumetric deformation. The effects of the quantity and properties of these asperities are investigated, and it is shown that the strength affects the macroscopic shear strength at both high and low confining pressures, while the effects of the number of asperities diminishes with increasing confining pressure due to asperity breakage. It is also shown that changing the number of asperities only affects the peak friction angle but not the ultimate friction angle by comparing the angles of repose of samples with different numbers of asperities
Empirical Models of Transitions between Coral Reef States: Effects of Region, Protection, and Environmental Change
There has been substantial recent change in coral reef communities. To date, most analyses have focussed on static patterns or changes in single variables such as coral cover. However, little is known about how community-level changes occur at large spatial scales. Here, we develop Markov models of annual changes in coral and macroalgal cover in the Caribbean and Great Barrier Reef (GBR) regions
Thermal Stress and Coral Cover as Drivers of Coral Disease Outbreaks
Very little is known about how environmental changes such as increasing temperature affect disease dynamics in the ocean, especially at large spatial scales. We asked whether the frequency of warm temperature anomalies is positively related to the frequency of coral disease across 1,500 km of Australia's Great Barrier Reef. We used a new high-resolution satellite dataset of ocean temperature and 6 y of coral disease and coral cover data from annual surveys of 48 reefs to answer this question. We found a highly significant relationship between the frequencies of warm temperature anomalies and of white syndrome, an emergent disease, or potentially, a group of diseases, of Pacific reef-building corals. The effect of temperature was highly dependent on coral cover because white syndrome outbreaks followed warm years, but only on high (>50%) cover reefs, suggesting an important role of host density as a threshold for outbreaks. Our results indicate that the frequency of temperature anomalies, which is predicted to increase in most tropical oceans, can increase the susceptibility of corals to disease, leading to outbreaks where corals are abundant
Regional Decline of Coral Cover in the Indo-Pacific: Timing, Extent, and Subregional Comparisons
A number of factors have recently caused mass coral mortality events in all of the world's tropical oceans. However, little is known about the timing, rate or spatial variability of the loss of reef-building corals, especially in the Indo-Pacific, which contains 75% of the world's coral reefs.We compiled and analyzed a coral cover database of 6001 quantitative surveys of 2667 Indo-Pacific coral reefs performed between 1968 and 2004. Surveys conducted during 2003 indicated that coral cover averaged only 22.1% (95% CI: 20.7, 23.4) and just 7 of 390 reefs surveyed that year had coral cover >60%. Estimated yearly coral cover loss based on annually pooled survey data was approximately 1% over the last twenty years and 2% between 1997 and 2003 (or 3,168 km(2) per year). The annual loss based on repeated measures regression analysis of a subset of reefs that were monitored for multiple years from 1997 to 2004 was 0.72 % (n = 476 reefs, 95% CI: 0.36, 1.08).The rate and extent of coral loss in the Indo-Pacific are greater than expected. Coral cover was also surprisingly uniform among subregions and declined decades earlier than previously assumed, even on some of the Pacific's most intensely managed reefs. These results have significant implications for policy makers and resource managers as they search for successful models to reverse coral loss
- …