2,668 research outputs found
How to harness the full potential of integrated catchment management as a pathway to sustainability
Water resource management authorities globally are increasingly adopting regional ecosystem approaches and reflexive governance as pathways to sustainable development (Paton et al., 2004; Vos et al.,2006). An integrated collaborative approach to natural resource management at the catchment scale is a strong theme in the recent literature (e.g., Lovell et al. 2002; Painter & Memon, 2008). New Zealandâs Resource Management Act (RMA), enacted in 1991, is a devolved planning mandate forintegrated natural resource management exercised by elected regional councils. The territorial jurisdiction of regional councils established in 1988 was purposely defined on the basis of groups of large water catchments (including groundwater aquifers) to facilitate an integrated approach to natural resource management. Integrated management of water allocation, water quality and related land management are primary functions of regional councils. However, regional councils have shied away from exercising their devolved integrated water planning mandate at the subregional catchment scale. Instead, provisions of first generation regional water plans tend to be framed region-wide in scope. In some plans, water quality and quantity issues are addressed separately with limited linkages, a reflection of poor integration
Electrically driven photon emission from individual atomic defects in monolayer WS2.
Quantum dot-like single-photon sources in transition metal dichalcogenides (TMDs) exhibit appealing quantum optical properties but lack a well-defined atomic structure and are subject to large spectral variability. Here, we demonstrate electrically stimulated photon emission from individual atomic defects in monolayer WS2 and directly correlate the emission with the local atomic and electronic structure. Radiative transitions are locally excited by sequential inelastic electron tunneling from a metallic tip into selected discrete defect states in the WS2 bandgap. Coupling to the optical far field is mediated by tip plasmons, which transduce the excess energy into a single photon. The applied tip-sample voltage determines the transition energy. Atomically resolved emission maps of individual point defects closely resemble electronic defect orbitals, the final states of the optical transitions. Inelastic charge carrier injection into localized defect states of two-dimensional materials provides a powerful platform for electrically driven, broadly tunable, atomic-scale single-photon sources
Effect of environmental conditions on the distribution of Pacific mackerel (Scomber japonicus) larvae in the California Current system
We modeled the probability of capturing Pacif ic mackerel
(Scomber japonicus) larvae as a function of environmental variables for the Southern California Bight (SCB) most years from 1951 through 2008 and Mexican waters offshore of
Baja California from 1951 through 1984. The model exhibited acceptable fit, as indicated by the area under a receiver-operating-characteristic curve of 0.80 but was inconsistent
with the zero catches that occurred frequently in the 2000s. Two types of spawners overlapped spatially within the survey area: those that exhibited peak spawning during
April in the SCB at about 15.5°C and a smaller group that exhibited peak spawning in August near Punta Eugenia, Mexico, at 20°C or greater. The SCB generally had greater zooplankton than Mexican waters but less appropriate (lower) geostrophic f lows. Mexican waters generally
exhibited greater predicted habitat quality than the SCB in cold years. Predicted quality of the habitat in the SCB was greater from the 1980s to 2008 than in the earlier years of the survey primarily because temperatures and geostrophic flows were more appropriate for larvae. However, stock
size the previous year had a larger effect on predictions than any environmental variable, indicating that larval Pacific mackerel did not fully occupy the suitable habitat during most years
Epistemic Two-Dimensionalism and Arguments From Epistemic Misclassification
According to Epistemic Two-Dimensional Semantics (E2D), expressions have a counterfactual intension and an epistemic intension. Epistemic intensions reflect cognitive significance such that sentences with necessary epistemic intensions are a priori. We defend E2D against an influential line of criticism: arguments from epistemic misclassification. We focus in particular on the arguments of Speaks [2010] and Schroeter [2005]. Such arguments conclude that E2D is mistaken from (i) the claim that E2D is committed to classifying certain sentences as a priori, and (ii) the claim that such sentences are a posteriori. We aim to show that these arguments are unsuccessful as (i) and (ii) undercut each other. One must distinguish the general framework of E2D from a specific implementation of it. The framework is flexible enough to avoid commitment to the apriority of any particular sentence; only specific implementations are so committed. Arguments from epistemic misclassification are therefore better understood as arguments for favouring one implementation of E2D over another, rather than as refutations of E2D
ONETEP + TOSCAM: uniting dynamical mean field theory and linear-scaling density functional theory
We introduce the unification of dynamical mean field theory (DMFT) and
linear-scaling density functional theory (DFT), as recently implemented in
ONETEP, a linear-scaling DFT package, and TOSCAM, a DMFT toolbox. This code can
account for strongly correlated electronic behavior while simultaneously
including the effects of the environment, making it ideally suited for studying
complex and heterogeneous systems containing transition metals and lanthanides,
such as metalloproteins. We systematically introduce the necessary formalism,
which must account for the non-orthogonal basis set used by ONETEP. In order to
demonstrate the capabilities of this code, we apply it to carbon
monoxide-ligated iron porphyrin and explore the distinctly quantum-mechanical
character of the iron electrons during the process of photodissociation.Comment: Contains 46 pages and 12 figures, including 5 pages of supplementary
materia
Hinode Calibration for Precise Image Co-alignment between SOT and XRT (November 2006 -- April 2007)
To understand the physical mechanisms for activity and heating in the solar
atmosphere, the magnetic coupling from the photosphere to the corona is an
important piece of information from the Hinode observations, and therefore
precise positional alignment is required among the data acquired by different
telescopes. The Hinode spacecraft and its onboard telescopes were developed to
allow us to investigate magnetic coupling with co-alignment accuracy better
than 1 arcsec. Using the Mercury transit observed on 8 November 2006 and
co-alignment measurements regularly performed on a weekly basis, we have
determined the information necessary for precise image co-alignment and have
confirmed that co-alignment better than 1 arcsec can be realized between Solar
Optical Telescope (SOT) and X-Ray Telescope (XRT) with our baseline
co-alignment method. This paper presents results from the calibration for
precise co-alignment of CCD images from SOT and XRT.Comment: 8 pages, 9 figures, accepted for publication in PASJ (Hinode Special
issue
Recycled water causes no salinity or toxicity issues in Napa vineyards
In response to Napa Sanitation District's interest in expanding its delivery of recycled
water to vineyards for irrigation, we conducted a feasibility study to assess the
suitability of the water for this use. We adopted two approaches: comparing the water
quality characteristics of the recycled water with those of other local sources of
irrigation water, and evaluating soil samples from a vineyard that was irrigated for
8 years with the recycled water. Results indicate that the quality of the recycled
water is suitable for irrigation, and also that long-term accumulation of salts and
toxic ions have not occurred in the vineyards studied and are unlikely to occur. Nutrients
in the recycled water may be beneficial to vineyards, though the levels of nitrogen
may need to be reduced by planting cover crops in some vineyards
Left hemisphere dominance for bilateral kinematic encoding in the human brain.
Neurophysiological studies in humans and nonhuman primates have revealed movement representations in both the contralateral and ipsilateral hemispheres. Inspired by clinical observations, we ask if this bilateral representation differs for the left and right hemispheres. Electrocorticography was recorded in human participants during an instructed-delay reaching task, with movements produced with either the contralateral or ipsilateral arm. Using a cross-validated kinematic encoding model, we found stronger bilateral encoding in the left hemisphere, an effect that was present during preparation and was amplified during execution. Consistent with this asymmetry, we also observed better across-arm generalization in the left hemisphere, indicating similar neural representations for right and left arm movements. Notably, these left hemisphere electrodes were centered over premotor and parietal regions. The more extensive bilateral encoding in the left hemisphere adds a new perspective to the pervasive neuropsychological finding that the left hemisphere plays a dominant role in praxis
Spatially Resolved Ultraviolet Spectroscopy of the Great Dimming of Betelgeuse
The bright supergiant, Betelgeuse (Alpha Orionis, HD 39801) experienced a
visual dimming during 2019 December and the first quarter of 2020 reaching an
historic minimum 2020 February 713. During 2019 September-November, prior to
the optical dimming event, the photosphere was expanding. At the same time,
spatially resolved ultraviolet spectra using the Hubble Space Telescope/Space
Telescope Imaging Spectrograph revealed a substantial increase in the
ultraviolet spectrum and Mg II line emission from the chromosphere over the
southern hemisphere of the star. Moreover, the temperature and electron density
inferred from the spectrum and C II diagnostics also increased in this
hemisphere. These changes happened prior to the Great Dimming Event. Variations
in the Mg II k-line profiles suggest material moved outwards in response to the
passage of a pulse or acoustic shock from 2019 September through 2019 November.
It appears that this extraordinary outflow of material from the star, likely
initiated by convective photospheric elements, was enhanced by the coincidence
with the outward motions in this phase of the 400 day pulsation cycle.
These ultraviolet observations appear to provide the connecting link between
the known large convective cells in the photosphere and the mass ejection event
that cooled to form the dust cloud in the southern hemisphere imaged in 2019
December, and led to the exceptional optical dimming of Betelgeuse in 2020
February.Comment: 11 pages, 8 figures, Astrophysical Journal, accepte
ACR Appropriateness CriteriaÂź Non-Spine Bone Metastases
Bone metastases are a common clinical problem, affecting many types of cancer patients. The presence of tumor in bone can cause significant morbidity including pain, neurological dysfunction, hypercalcemia, and pathological fracture leading to functional loss. The optimal treatment of a patient with bone metastases depends on many factors, including evaluation of the patient's goals of care, performance status, mechanical stability of the affected bone, life expectancy, and overall extent of disease. Treatment options may include radiotherapy, systemic therapies, surgical stabilization, medical pain management, and radiopharmaceuticals. Ideal management of bone metastases requires a coordinated multidisciplinary approach among diagnostic radiologists, radiation oncologists, medical oncologists, orthopedic surgeons, pain specialists, physiatrists, and palliative care specialists. The American College of Radiology Appropriateness Criteria? are evidence-based guidelines for specific clinical conditions that are reviewed every 3 years by a multidisciplinary expert panel. The guidelines development and review include an extensive analysis of current medical literature from peer-reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances where evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/140118/1/jpm.2014.9395.pd
- âŠ