Arsenic in the Water, Soil Bedrock, and Plants of the Ester Dome Area of Alaska

Concentrations of arsenic as large as 10 ppm (200 times the safe limit for drinking water) occur in the groundwater of a mineralized residential area near Fairbanks. Bedrock of the area contains 750 ppm As, primarily as arsenopyrite and scorodite. The oxygen-poor groundwater is enriched in As(III) and ferrous iron while the surface waters are iron free and contain less than 50 ppb As(V). Arsenic is removed from the water by coprecipitation with ferric hydroxide. Some iron-rich stream sediments contain as much as 1,400 ppm arsenic. The distribution of arsenic in the groundwater is controlled by the distribution of arsenic in the bedrock. The arsenic content of the B soil horizon over mineralized veins is about 150 ppm, while that over barren rock is 30 ppm. The vegetation over the veins is not significantly enriched in arsenic. Lettuce, radishes and tomatoes grown with arsenic-rich water (5 ppm) contain 16, 8 and 1 ppm As, respectively; these amounts are significantly greater than plants not treated with arsenic. Preliminary studies by state and federal health agencies show no detrimental effects on the health of persons drinking these arsenic-rich waters.The work upon which this publication is based was supported in part by funds provided by the Office of Water Research and Technology (Project B-037-ALAS, Agreement No. 14-34-0001-8056), U.S. Department of the Interior, Washington, D.C., as authorized by the Water Research and Development Act of 1978

Teachers\u27 attitudes toward the inclusion of young children with special needs into regular early childhood classes

All children have special abilities and special needs that make them unique individuals. Most teachers work with children who have a wide range of abilities and learning styles. Early childhood teachers are no exception. They may have children enrolled in their classrooms who have subtle learning disabilities, significant physical, mental or emotional problems, high intelligence, or conditions which limit speech and motor development. Teachers may not have been taught that the continuum of development is similar for all children, but that timetables may vary. This thesis examines staff attitudes toward the placement of young children with special needs into regular daycare or preschool classes – a philosophy called inclusion. Most early childhood professionals have preservice training in either regular or special education. In the real world, people\u27s abilities are not so well defined; why then should teacher training be separated into two distinct categories? Do teachers with regular education backgrounds feel prepared to work with children who are developing atypically in some areas? What are teachers prepared to teach? What are they not prepared to teach? How do they manage their classrooms? Do they know what to do and how to do it? To find answers to these and other questions, this researcher reviewed current literature relevant to inclusion, particularly for inclusion at the preschool level. The literature abounds with research which shows that regular education teachers tend to have a sparse background in teaching techniques and strategies for particular special needs. They may lack assessment skills and be unaware of signals which can point to problems. They may not have been taught that the continuum of development is similar for all children, but that individual timetables may vary. This study surveyed staff attitudes toward inclusion m three different areas. These areas include attitudes toward inclusion, preservice and inservice training, and collaboration. Thirty-nine female teachers, employed at one of five selected early childhood centers, participated in the survey. They answered a five point Likert scale questionnaire with 27 questions pertaining to each of the three areas noted. Responses were organized and tallied to yield mean scores and standard deviations for each cluster of questions. Comparisons between centers were determined from results of paired t-tests. This study yielded overall results toward the positive side, although responses ranged through all five points on the scale

Tightness of the skin over the feet and lower limbs associated with haemosiderosis

No Abstract

Extending the Globular Cluster System-Halo Mass Relation to the Lowest Galaxy Masses

High mass galaxies, with halo masses $M_{200} \ge 10^{10} M_{\odot}$, reveal a remarkable near-linear relation between their globular cluster (GC) system mass and their host galaxy halo mass. Extending this relation to the mass range of dwarf galaxies has been problematic due to the difficulty in measuring independent halo masses. Here we derive new halo masses based on stellar and HI gas kinematics for a sample of nearby dwarf galaxies with GC systems. We find that the GC system mass--halo mass relation for galaxies populated by GCs holds from halo masses of $M_{200} \sim 10^{14} M_{\odot}$ down to below $M_{200}$ $\sim 10^9 M_{\odot}$, although there is a substantial increase in scatter towards low masses. In particular, three well-studied ultra diffuse galaxies, with dwarf-like stellar masses, reveal a wide range in their GC-to-halo mass ratios. We compare our GC system--halo mass relation to the recent model of El Badry et al., finding that their fiducial model does not reproduce our data in the low mass regime. This may suggest that GC formation needs to be more efficient than assumed in their model, or it may be due to the onset of stochastic GC occupation in low mass halos. Finally, we briefly discuss the stellar mass-halo mass relation for our low mass galaxies with GCs, and we suggest some nearby dwarf galaxies for which searches for GCs may be fruitful.Comment: 16 pages, 5 figures, accepted for publication in MNRA

Age Estimates for Galaxies in Groups

We discuss recent developments on the age and metallicity distribution for early type galaxies in different environments.Comment: 4 pages, Latex, 2 figures, submitted to IAU 17

Taking the Quantum Eraser to the Abstract World

Youngs double slit experiment is one of the most celebrated achievements in quantum and classical optics; it provides experimental proof of the wave-particle duality of light. When the paths of the double slit are marked with orthogonal polarizations, the path information is revealed and no interference pattern is observed. However, the path information can be erased with a complimentary analysis of the polarization. Here we use hybrid entanglement between photons carrying orbital angular momentum and polarization to show that, just as in Young's experiment, the paths (OAM) marked with polarization do not lead to interference. However, when introducing the eraser (polarizer) which projects the polarization of one of the entangled photons onto a complementary polarization basis, the OAM (paths) are allowed to interfere, leading to the formation of azimuthal fringes whose frequency is proportional to the OAM content carried by the photon

Effects on the Function of Three Trophic Levels in Marine Plankton Communities under Stress from the Antifouling Compound Zinc Pyrithione

This study aimed to investigate functional responses of natural marine planktonic communities to stress from the antifouling compound zinc pyrithione (ZPT). Isotope labelling techniques (14C) were applied to study bacterial incorporation of leucine, photosynthetic activity of phytoplankton and grazing of labelled prey by zooplankton communities for 6 days after exposures to nominal concentrations of 0, 5, 25, 50 nM ZPT in a mesocosm experiment in Isefjord, Denmark. Significant direct effects were visible on chlorophyll α concentrations, which decreased in all exposed communities, to between 48 and 36% of control concentrations on Day 3, 1 day after the last exposure. Phytoplankton activities were also significantly affected on Day 3 with activities between 9 and 26% of control levels, as was zooplankton activities in the 25 and 50 nM exposures. In the 50 nM exposure the total community zooplankton activity was reduced to 25 ± 4%, and per individual to 46 ± 11% of control levels. Bacterial communities showed positive indirect effects with high activities (up to 183 ± 40%) due to higher amounts of available substrate from algal death. Pollution induced community tolerance analyses performed on phytoplankton and bacterial communities at the end of the experiment indicated a development of increased tolerance for phytoplankton in the 50 nM exposed communities, whereas there were no changes in tolerance in the bacterial communities. Multivariate analysis of the integrated functional response by the plankton communities revealed a significant difference (p \u3c 0.05) between exposed communities compared to controls in the first 3 days after last exposure and in the end of the experiment. The study provides evidence of diverse effects on the functions of marine plankton communities under stress from a pollutant. Direct effects lead to cascading indirect effects throughout the community, eventually causing different developments. Continuous exposure to ZPT could lead to severe long-term effects, causing more permanent changes in structure and function than observed here. The study demonstrates that it is possible to assess the functional effects of a stressor in a complex mesocosm system, and to determine effects in a complex plankton community, which were not predictable from laboratory studies

Knowledge, attitudes and practices of medical staff towards obesity management in patients with spinal cord injuries: an International survey of four western European countries

Objective: To (1) examine the opinions of medical staff working in spinal cord injury (SCI) centres (SCICs); (2) evaluate their knowledge, attitudes and practices towards obesity prevention and management; (3) report the number of beds and dietitians available at each SCIC. Methods: A 37-item questionnaire was sent to 23 SCICs in the UK, the Netherlands, Belgium and the Republic of Ireland between September 2012 and January 2013. Results: Eighteen SCICs returned the questionnaires for analysis. All respondents stated that they had an interest in obesity treatment but only 2.3% of the respondents received training in obesity management. Sixty-one percent of staff did not consider body mass index (BMI) to be appropriate for use in SCI patients and subsequently less than half of the respondents use BMI routinely. The majority of respondents reported that they are confident in dealing with overweight (74.5%) and obese (66.1%) SCI adults, less than half (44.1%) are confident in treating overweight and obese SCI children. Respondents also indicated the need for nationally adopted guidelines and a lack of physical activity provision. There were 17.5 whole-time equivalent (WTE) dietitians recorded in 22 SCICs, equivalent to 47.8 beds per WTE dietitians (range 10–420). Non-UK SCIC dietitians are significantly better resourced than in UK SCICs (beds per WTE dietitian: 36 vs 124, P=0.035). Conclusion: Medical staff expressed the need to participate in obesity prevention and management. Appropriate training should be considered for all medical staff and the development of specific weight management guidelines and dietetic provision should be considered

Zero Temperature Thermodynamics of Asymmetric Fermi Gases at Unitarity

The equation of state of a dilute two-component asymmetric Fermi gas at unitarity is subject to strong constraints, which affect the spatial density profiles in atomic traps. These constraints require the existence of at least one non-trivial partially polarized (asymmetric) phase. We determine the relation between the structure of the spatial density profiles and the T=0 equation of state, based on the most accurate theoretical predictions available. We also show how the equation of state can be determined from experimental observations.Comment: 10 pages and 7 figures. (Minor changes to correspond with published version.