105,812 research outputs found
Flexible composite membrane Patent
Flexible composite membrane structure impervious to extremely reactive chemicals in rocket propellant
The WHO Global Code of Practice on the International Recruitment of Health Personnel: The Evolution of Global Health Diplomacy
The May 2010 adoption of the World Health Organization Global Code of Practice on the International Recruitment of Health Personnel created a global architecture, including ethical norms and institutional and legal arrangements, to guide international cooperation and serve as a platform for continuing dialogue on the critical problem of health worker migration. Highlighting the contribution of non-binding instruments to global health governance, this article describes the Code negotiation process from its early stages to the formal adoption of the final text of the Code. Detailed are the vigorous negotiations amongst key stakeholders, including the active role of non-governmental organizations. The article emphasizes the importance of political leadership, appropriate sequencing, and support for capacity building of developing countries’ negotiating skills to successful global health negotiations. It also reflects on how the dynamics of the Code negotiation process evidence an evolution in global health negotiations amongst the WHO Secretariat, civil society, and WHO Member States
Polarizability of molecular hydrogen
Static dipole electric polarizabilities of molecular hydroge
Recommended from our members
Addressing barriers to learning: In the classroom and schoolwide.
IntroductionPublic education is at a crossroads. Moving in new directions is imperative. Just tweaking and tinkering with old ideas is a recipe for disaster.Continuing challenges confronting public education highlight why moving school improvement policy and practice in new directions is imperative. With a view to enhancing graduation rates and successful transitions to post-secondary opportunities and well-being, pressing challenges include:Increasing equity of opportunity for every student to succeed, narrowing the achievement gap, and countering the school to prison pipeline Reducing unnecessary referrals for special assistance and special education; Improving school climate and retaining good teachers Reducing the number of low performing schools.As education leaders well know, meeting these challenges requires making sustainable progress inimproving supports for specific subgroups (e.g., English Learners, immigrant newcomers, lagging minorities, homeless students, students with disabilities) increasing the number of disconnected students who re-engage in classroom learning and thus improving attendance, reducing disruptive behaviors (e.g., including bullying and sexual harassment), and decreasing suspensions and dropouts increasing family and community engagement with schools responding effectively when schools experience crises events and preventing crises whenever possible.In some schools, continuous progress related to these concerns is being made. For many districts, however, sustainable progress remains elusive – and will continue to be so as long as the focus of school improvement policy and practice is mainly on improving instruction. Efforts to expand the use of instructional technology, develop new curriculum standards, make teachers more accountable, and improve teacher preparation and licensing all have merit; but they are insufficient for addressing the many everyday barriers to learning and teaching that interfere with effective student engagement in classroom instruction.Most policy makers and administrators know that good instruction delivered by highly qualified teachers cannot ensure that all students have an equal opportunity to succeed at school.Even the best teacher can’t do the job alone. Teachers need student and learning supports in the classroom and schoolwide in order to personalize instruction and provide special assistance when students manifest learning, behavior, and emotional problems. Unfortunately, school improvement plans continue to give short shrift to these critical matters.We recognize, as did a Carnegie Task Force on Education, that school systems are not responsible for meeting every need of their students. But as the task force stressed: when the need directly affects learning, the school must meet the challenge.The most pressing challenge is to enhance equity of opportunity by fundamentally improving how schools address barriers to learning and teaching. The future of public education depends on moving in new directions to accomplish this.Now is the time to fundamentally transform how schools address factors that keep too many students from doing well at school. And while transformation is never easy, pioneering work across the country is showing the way. Trailblazers are redeploying existing funds allocated for addressing barriers to learning and weaving these together with the invaluable resources that can be garnered by collaboration with other agencies and with community stakeholders, family members, and students themselves.The first step in moving forward is to escape old ideas. The second step is to incorporate a new vision in school improvement planning for addressing barriers to learning and teaching and re-engaging disconnected students. Our analyses envision a plan that designs and develops a unified, comprehensive, and equitable system of student and learning supports. The third step is to develop a strategic plan for systemic change, scale-up, and sustainability.This book highlights each of these matters. We invite you to join us in the quest to enhance equity of opportunity for all students to succeed at school and beyond. And we look forward to hearing from you about moving schools forward to make the rhetoric of the Every Student Succeeds Act a reality
Fabrication of lightweight Si/SiC LIDAR mirrors
A new, chemical vapor deposition (CVD) process was developed for fabricating lightweight, polycrystalline silicon/silicon-carbide (Si/SiC) mirrors. The process involves three CVD steps: (1) to produce the mirror faceplate; (2) to form the lightweight backstructure, which is deposited integral to the faceplate; and (3) to deposit a layer of optical-grade material, e.g., Si, onto the front surface of the faceplate. The mirror figure and finish are fabricated into the faceplate
Competing Adiabatic Thouless Pumps in Enlarged Parameter Spaces
The transfer of conserved charges through insulating matter via smooth
deformations of the Hamiltonian is known as quantum adiabatic, or Thouless,
pumping. Central to this phenomenon are Hamiltonians whose insulating gap is
controlled by a multi-dimensional (usually two-dimensional) parameter space in
which paths can be defined for adiabatic changes in the Hamiltonian, i.e.,
without closing the gap. Here, we extend the concept of Thouless pumps of band
insulators by considering a larger, three-dimensional parameter space. We show
that the connectivity of this parameter space is crucial for defining quantum
pumps, demonstrating that, as opposed to the conventional two-dimensional case,
pumped quantities depend not only on the initial and final points of
Hamiltonian evolution but also on the class of the chosen path and preserved
symmetries. As such, we distinguish the scenarios of closed/open paths of
Hamiltonian evolution, finding that different closed cycles can lead to the
pumping of different quantum numbers, and that different open paths may point
to distinct scenarios for surface physics. As explicit examples, we consider
models similar to simple models used to describe topological insulators, but
with doubled degrees of freedom compared to a minimal topological insulator
model. The extra fermionic flavors from doubling allow for extra gapping
terms/adiabatic parameters - besides the usual topological mass which preserves
the topology-protecting discrete symmetries - generating an enlarged adiabatic
parameter-space. We consider cases in one and three \emph{spatial} dimensions,
and our results in three dimensions may be realized in the context of
crystalline topological insulators, as we briefly discuss.Comment: 21 pages, 7 Figure
Heat and Mass Transfer in Cold Regions Soils
The work upon which this report is based was made possible by a cooperative
aid agreement between the U.S. Forest Service, Institute of Northern
Forestry, Fairbanks, Alaska, and the Institute of Water Resources, University
of Alaska. Contributions to this study were also made by the University of
California at Davis and Ohio State University. The collection of winter
data on pore pressures was made possible by a separate grant by the Office
of Water Research and Technology (project A-053 ALAS)
Hydrologic Properties of Subarctic Organic Soils
Completion Report
for
U. S. Forest Service
Institute of Northern Forestry
Cooperative Agreement No. 16 USC 581; 581a-581iThe need for understanding the natural system and how it responds
to various stresses is important; this is especially so in an environment
where the climate not only sustains permafrost, but develops
massive seasonal frost as well. Consequently, the role of the shallow
surface organic layer is also quite important. Since a slight change in
the soil thermal regime may bring about a phase change in the water or
ice, therefore, the system response to surface alterations such as
burning can be quite severe. The need for a better understanding of the
behavior and properties of the organic layer is, therefore, accentuated.
The central theme of this study was the examination of the hydrologic
and hydraulic properties of subarctic organic soils. Summarized
in this paper are the results of three aspects of subarctic organic soil
examinations conducted during the duration of the project. First, a
field site was set up in Washington Creek with the major emphasis on
measuring numerous variables of that soil system during the summer. The
greatest variations in moisture content occur in the thick organic soils
that exist at this site. Our major emphasis was to study the soil
moisture levels in these soils. This topic is covered in the first
major section, including associated laboratory studies. Those laboratory
studies include investigations of several hydraulic and hydrologic
properties of taiga organic and mineral soils. Second, some field data
on organic moisture levels was collected at the site of prescribed burns
in Washington Creek to ascertain the sustainability of fires as a function
of moisture levels. This portion of the study is described under the
second major heading. The last element of this study was a continued
application of the two-dimensional flow model that was developed in an
earlier study funded by the U. S. Forest Service, Institute of Northern
Forestry, and reported by Kane, Luthin, and Taylor (1975a).
Many of the results and concepts gathered in the field work were
integrated into the modeling effort, which is aimed at producing better
estimates of the hydrologic effects of surface disturbances in the black
spruce taiga subarctic ecosystem. This knowledge should also contribute
to better fire management decisions of the same system.The work upon which this report is based was made possible by a
cooperative aid agreement funded by the U. S. Forest Service, Institute
of Northern Forestry, Fairbanks, Alaska. Contribution to this study was
also made by Ohio State University
Ringing the Randall-Sundrum braneworld: metastable gravity wave bound states
In the Randall-Sundrum scenario, our universe is a 4-dimensional `brane'
living in a 5-dimensional bulk spacetime. By studying the scattering of bulk
gravity waves, we show that this brane rings with a characteristic set of
complex quasinormal frequencies, much like a black hole. To a bulk observer
these modes are interpreted as metastable gravity wave bound states, while a
brane observer views them as a discrete spectrum of decaying massive gravitons.
Potential implications of these scattering resonances are discussed.Comment: References and misc. comments added. "Implications" section expanded.
REVTeX4, 5 pages, 4 figure
Mesomorphic properties of alkoxybenzylidene- aminoacetophenones
Liquid crystal phase transitions in compounds of alkoxybenzylidene-aminoacetophene serie
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