624 research outputs found
A preferred vision for administering secondary schools : a reflective essay
This reflective paper will address four areas, which are important components of a learning community. First, the importance of a positive school climate, and how this plays an integral part in the creation of the learning community. Second, to look at character education and a shift in discipline policies to help prepare students for our changing society. Third, a paradigm shift from extra curricular to co-curricular educational opportunities for our student body. Fourth, a look at educational leadership in developing the learning community
Using Large Databases of Groundwater Chemistry in the Northern Midwest USA: The Effects of Geologic and Anthropogenic Factors
Regional geochemical databases for the northern Midwest USA are being compiled to examine the various geogenic and anthropogenic factors that control the chemistry of groundwater. At the regional scale, variations are seen that are attributable to agricultural and urban effects, or to geologic factors. Examples of the former include enrichments of nitrate in groundwater, while examples of the latter mainly highlight geochemical differences between carbonate rocks and all other rock types in the region. This paper examines a few of these regional effects and the spatial scales at which they can be observe
Atrazine Degradation in a Small Stream in Iowa
A study was conducted during 1990 through an 11.2-km reach of Roberts Creek in northeastern Iowa to determine the fate of atrazine in a surface water environment. Water samples were collected at ~1-month intervals from April through November during stable low to medium flow conditions and analyzed for atrazine and two of its initial biotic degradation products, desethylatrazine and deisopropylatrazine. Samples were collected on the basis of a Lagrangian model of streamflow in order to sample the same parcel of water as it moved downstream. Atrazine concentrations substantially decreased (roughly 25-60% ) between water entering and exiting the study reach during four of the seven sampling periods. During these same four sampling periods, the concentrations of the two biotic atrazine degradation products were constant or decreasing downstream, suggesting an abiotic degradation process
Non-equilibrium dynamics of electron emission from cold and hot graphene under proton irradiation
Characteristic properties of secondary electrons emitted from irradiated
two-dimensional materials arise from multi-length and time-scale relaxation
processes that connect the initial non-equilibrium excited electron
distribution with their eventual emission. To understand these processes, which
are critical for using secondary electrons as high-resolution thermalization
probes, we combine first-principles real-time electron dynamics with modern
experiments. Our data for cold and hot proton-irradiated graphene shows
signatures of kinetic and potential emission and generally good agreement for
electron yields between experiment and theory. The duration of the emission
pulse is about 1.5 femtoseconds, indicating high time resolution when used as a
probe. Our newly developed method to predict kinetic energy spectra shows good
agreement with electron and ion irradiation experiments and prior models. We
find that lattice temperature significantly increases secondary electron
emission, whereas electron temperature has a negligible effect
Ultra-large polymer-free suspended graphene films
Due to its extraordinary properties, suspended graphene is a critical element
in a wide range of applications. Preparation methods that preserve the unique
properties of graphene are therefore in high demand. To date, all protocols for
the production of large graphene films have relied on the application of a
polymer film to stabilize graphene during the transfer process. However, this
inevitably introduces contaminations that have proven to be extremely
difficult, if not impossible, to remove entirely. Here we report the
polymer-free fabrication of suspended films consisting of three graphene layers
spanning circular holes of 150 m diameter. We find a high fabrication
yield, very uniform properties of the freestanding graphene across all holes as
well across individual holes. A detailed analysis by confocal Raman and THz
spectroscopy reveals that the triple-layer samples exhibit structural and
electronic properties similar to those of monolayer graphene. We demonstrate
their usability as ion-electron converters in time-of-flight mass spectrometry
and related applications. They are two orders of magnitude thinner than
previous carbon foils typically used in these types of experiments, while still
being robust and exhibiting a sufficiently high electron yield. These results
are an important step towards replacing free-standing ultra-thin carbon films
or graphene from polymer-based transfers with much better defined and clean
graphene.Comment: 9 pagers, 5 figure
Table-top soft x-ray source for XAS experiments with photon energies up to 350 eV
We present a table-top setup for femtosecond x-ray absorption spectroscopy
based on high harmonic generation (HHG) in noble gases. Using sub-millijoule
pump pulses at a central wavelength of 1550 nm broadband HHG in the range 70 to
350 eV was demonstrated. The HHG coherence lengths of several millimeters were
achieved by reaching the nonadiabatic regime of harmonic generation. NEXAFS
experiments on the boron K edge of a boron foil and a hexagonal BN (hBN) 2D
material demonstrate the capabilities of the setup
It became easier once I knew: Stakeholder perspectives for educating children and teenagers about their difference of sex development.
OBJECTIVE: Secrecy about a childs difference of sex development (DSD) can lead to internalized shame and stigma. We explored how teenagers and adults with DSD, parents, healthcare providers, and allied professionals value and perceive patient education. METHODS: Stakeholders (n = 110) completed qualitative semi-structured interviews. Relevant themes for educational content were queried and organized. RESULTS: Education was consistently identified as essential to successful outcomes. There was less consistency in how to educate patients. Disagreement existed regarding who should champion the education process. Participants believed medically relevant information should be shared gradually with attention to developmental capacity. Details were lacking regarding how much or what information to share. Participants noted that vetted resources were helpful. Benefits of sharing condition-specific information with patients included supporting their psychosocial development. Barriers included parental resistance to sharing information due to shame/stigma, and cultural and/or family dynamics. CONCLUSIONS: Stakeholders different perspectives regarding patient DSD education warrant future research to focus on the design, evaluation, and implementation of education-focused interventions. PRACTICE IMPLICATIONS: Healthcare providers are responsible for supporting the education of children and teenagers with DSD about their condition. When considering barriers, adopting a cultural or family systems framework can reduce parental resistance and promote open dialogue
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