Integrating Supervised and Unsupervised Classification Methods to Develop a More Accurate Land Cover Classification

The classification and mapping of land cover provides fundamental information about the characteristics, activities, and status of specific areas on the earth\u27s surface. The quality of the final classification is critical in providing accurate information for ecologists and resource managers in decision-making and for developing a landscape-level understanding of an ecosystem. A land cover classification was developed for 5 research watersheds in Garland and Saline counties in Arkansas using 2002 LANDSAT7 Enhanced Thematic Mapper Plus (ETM+) satellite imagery. The supervised classification was based upon 146 training areas identified from reference data and then applied to the imagery using the maximum likelihood classification algorithm. The unsupervised classification used an Iterative Self-Organizing Data Analysis Techniques (ISODATA) algorithm to classify the imagery into 300 spectral classes which then were identified from reference data. Data from 171 field locations were used to assess the accuracy of the final classifications using an error matrix. The supervised classification had an overall accuracy of 74.85% compared to 40.94% for the unsupervised classification. However, the dense canopy pine plantation class, which comprises 10.69% of the total area of the watersheds (1,216.69 ha), was more accurately classified in the unsupervised classification (64.29%) than the supervised classification (43.86%). The unsupervised classification of dense canopy pine plantation was incorporated into the supervised classification to produce a final integrated classification with an improved overall accuracy of 76.61%. We found that, where greater accuracy is desired, both classification methods should be used and the results integrated to utilize each method\u27s strengths

Quenched chirality in RbNiCl3_3

The critical behaviour of stacked-triangular antiferromagnets has been intensely studied since Kawamura predicted new universality classes for triangular and helical antiferromagnets. The new universality classes are linked to an additional discrete degree of freedom, chirality, which is not present on rectangular lattices, nor in ferromagnets. However, the theoretical as well as experimental situation is discussed controversially, and generic scaling without universality has been proposed as an alternative scenario. Here we present a careful investigation of the zero-field critical behaviour of RbNiCl$_3$, a stacked-triangular Heisenberg antiferromagnet with very small Ising anisotropy. From linear birefringence experiments we determine the specific heat exponent $\alpha$ as well as the critical amplitude ratio $A^+/A^-$. Our high-resolution measurements point to a single second order phase transition with standard Heisenberg critical behaviour, contrary to all theoretical predictions. From a supplementary neutron diffraction study we can exclude a structural phase transition at T$_N$. We discuss our results in the context of other available experimental results on RbNiCl$_3$ and related compounds. We arrive at a simple intuitive explanation which may be relevant for other discrepancies observed in the critical behaviour of stacked-triangular antiferromagnets. In RbNiCl$_3$ the ordering of the chirality is suppressed by strong spin fluctuations, yielding to a different phase diagram, as compared to e.g.\@ CsNiCl$_3$, where the Ising anisotropy prevents these fluctuations

Low dimensional ordering and fluctuations in methanol-β\beta-hydroquinone-clathrate studied by X-ray and neutron diffraction

Methanol-$\beta$-hydroquinone-clathrate has been established as a model system for dielectric ordering and fluctuations and is conceptually close to magnetic spin systems. In X-ray and neutron diffraction experiments, we investigated the ordered structure, the one-dimensional (1D) and the three-dimensional (3D) critical scattering in the paraelectric phase, and the temperature dependence of the lattice constants. Our results can be explained by microscopic models of the methanol pseudospin in the hydroquinone cage network, in consistency with previous dielectric investigations

Using a Geographical Information System to Evaluate Contributing Factors to Deer-Vehicle Collisions

An expanding human population combined with a growing white-tailed deer (Odocoifeus virginianus) population has resulted in an increase of deer-vehicle collisions in Arkansas. In response to this increase, we are using spatially explicit datasets integrated within a geographic information system (GIS) to identify county-level and site-specific factors contributing to deer-vehicle collisions. County-level information, such as human population densities /urbanization, deer density indices, and road densities, is being evaluated for use in identifying potential aggregations of deer-vehicle collisions. Site-specific information being evaluated includes physical factors such as landcover composition and arrangement, topography, and road characteristics. By incorporating these multi-scale data sets in a GIS, spatial intersections of variables indicating potential current or future hotspots of deer-vehicle collisions can be identified and mapped. This information can then be used to aid administrators and natural resource managers in identifying locations where deer-vehicle collisions may be concentrated

Root cortex development is fine-tuned by the interplay of MIGs, SCL3 and DELLAs during arbuscular mycorrhizal symbiosis

Root development is a crucial process that determines the ability of plants to acquire nutrients, adapt to the substrate and withstand changing environmental conditions. Root plasticity is controlled by a plethora of transcriptional regulators that allow, in contrast to tissue development in animals, post-embryonic changes that give rise to new tissue and specialized cells. One of these changes is the accommodation in the cortex of hyperbranched hyphae of symbiotic arbuscular mycorrhizal (AM) fungi, called arbuscules. Arbuscule-containing cells undergo massive reprogramming to coordinate developmental changes with transport processes. Here we describe a novel negative regulator of arbuscule development, MIG3. MIG3 induces and interacts with SCL3, both of which modulate the activity of the central regulator DELLA, restraining cortical cell growth. As in a tug-of-war, MIG3-SCL3 antagonizes the function of the complex MIG1-DELLA, which promotes the cell expansion required for arbuscule development, adjusting cell size during the dynamic processes of the arbuscule life cycle. Our results in the legume plant Medicago truncatula advance the knowledge of root development in dicot plants, showing the existence of additional regulatory elements not present in Arabidopsis that fine-tune the activity of conserved central modules

Spin correlations and exchange in square lattice frustrated ferromagnets

The J1-J2 model on a square lattice exhibits a rich variety of different forms of magnetic order that depend sensitively on the ratio of exchange constants J2/J1. We use bulk magnetometry and polarized neutron scattering to determine J1 and J2 unambiguously for two materials in a new family of vanadium phosphates, Pb2VO(PO4)2 and SrZnVO(PO4)2, and we find that they have ferromagnetic J1. The ordered moment in the collinear antiferromagnetic ground state is reduced, and the diffuse magnetic scattering is enhanced, as the predicted bond-nematic region of the phase diagram is approached.Comment: 4 pages, 4 figure

Novel Polyoxometalate- Ionic Liquid with Antibacterial and Antifungal Properties. Feasibility of Its Implementation As a Multifunctional Thin Coating

The synthesis of hybrid materials, combining the properties of organic and inorganic components, results in composites with unique physical and chemical features. Polyoxometalates (POMs), i.e. inorganic anionic molecular metal oxides, are considered as promising future metallodrugs due to their antiviral, antitumoral and antibacterial activities. The combination of bulky organic cations with POMs results in composite ionic liquids (IL; melting point below 100°C) which combine the unique properties of both components. Pioneering studies have used composites of alkylammonium cations and POM anions for multifunctional water purification to remove toxic heavy materials, organic aromatics and microbes and for the inhibition of bio-corrosion on metal and stone surfaces due to coating formation.Fil: Enderle, Ana Gabriela. Universidad Nacional del Litoral; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Streb, C.. Universitat Ulm; AlemaniaFil: Bollini, Mariela. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Centro de Investigaciones en Bionanociencias "Elizabeth Jares Erijman"; ArgentinaFil: Culzoni, Maria Julia. Universidad Nacional del Litoral. Facultad de Bioquímica y Ciencias Biológicas. Departamento de Química. Cátedra de Química Analítica; ArgentinaFil: Mitchell, S. G.. Universidad de Zaragoza; EspañaFil: Franco Castillo, I.. Universidad de Zaragoza; España2019 AIChE Annual MeetingOrlandoEstados UnidosAmerican Institute of Chemical Engineer

Dominant ferromagnetism in the spin-1/2 half-twist ladder 334 compounds, Ba3Cu3In4O12 and Ba3Cu3Sc4O12

The magnetic properties of polycrystalline samples of Ba3Cu3In4O12 (In-334) and Ba3Cu3Sc4O12 (Sc-334) are reported. Both 334 phases have a structure derived from perovskite, with CuO4 squares interconnected to form half-twist ladders along the c-axis. The Cu-O-Cu angles, ~ 90o, and the positive Weiss temperatures indicate the presence of significant ferromagnetic (FM) interactions along the Cu ladders. At low temperatures, T < 20 K, sharp transitions in the magnetic susceptibility and heat capacity measurements indicate three-dimensional (3D) antiferromagnetic (AFM) ordering at TN. TN is suppressed on application of a field and a complex magnetic phase diagram with three distinct magnetic regimes below the upper critical field can be inferred from our measurements. The magnetic interactions are discussed in relation to a modified spin-1/2 FM-AFM model and the 334 half-twist ladder is compared to other 2-rung ladder spin-1/2 systems.Comment: 20 pages, 7 figure

Magnetic-field-induced spin excitations and renormalized spin gap of the underdoped superconductor La1.895_{1.895}Sr0.105_{0.105}CuO4_{4}

High-resolution neutron inelastic scattering experiments in applied magnetic fields have been performed on La$_{1.895}$Sr$_{0.105}$CuO$_{4}$ (LSCO). In zero field, the temperature dependence of the low-energy peak intensity at the incommensurate momentum-transfer $\mathbf{Q}^{\ }_{\mathrm{IC}}=(0.5,0.5\pm\delta,0),(0.5\pm\delta,0.5,0)$exhibits an anomaly at the superconducting$T^{\}_{c}$ which broadens and shifts to lower temperature upon the application of a magnetic field along the c-axis. A field-induced enhancement of the spectral weight is observed, but only at finite energy transfers and in an intermediate temperature range. These observations establish the opening of a strongly downward renormalized spin gap in the underdoped regime of LSCO. This behavior contrasts with the observed doping dependence of most electronic energy features.Comment: accepted for publication in Phys. Rev. Let

Population level effectiveness of implementing collaborative care management for depression

AbstractObjectiveCare management is feasible to deploy in routine care, and the depression outcomes of patients reached by this evidence-based practice are similar to those observed in randomized controlled trials. However, no studies have estimated the population level effectiveness of care management when deployed in routine care. Population level effectiveness depends on both reach into the target population and the clinical effectiveness for those reached.MethodThis multisite hybrid Type 3 effectiveness–implementation study employed a pre-post, quasi-experimental design. The study was conducted at 22 Veterans Affairs community-based outpatient clinics. Evidence-based quality improvement was used as the facilitation strategy to promote adoption. Medication possession ratios (MPRs) were calculated for 1558 patients with an active antidepressant prescription. Differences in treatment response rates at implementation and control sites were estimated from observed differences in MPR.ResultsReach into the target population at implementation sites was 10.3%. Patients at implementation sites had a significantly higher probability of having MPR≥0.9 than patients at control sites [odds ratio=1.38, confidence interval95=(1.07, 1.78), P=.01]. This increase in MPR was estimated to yield a 1% point increase in response rates.ConclusionsWhile depression care management improves outcomes for patients receiving services, low levels of reach can reduce overall population level effectiveness