3,253 research outputs found
Barriers to recovery and recommendations for change: the Pennsylvania Consensus Conference on psychiatry\u27s role.
OBJECTIVE: Recovery has emerged over the past decade as a dominant theme in public mental health care.
METHODS: The 2006 Pennsylvania Consensus Conference brought together 24 community psychiatrists to explore the barriers they experienced in promoting recovery and their recommendations for change.
RESULTS: Twelve barriers were identified and classified into one of three categories: psychiatry knowledge, roles, and training; the need to transform public mental health systems and services; and environmental barriers to opportunity. Participants made 22 recommendations to address these barriers through changes in policies, programs, and psychiatric knowledge and practice.
CONCLUSIONS: The recommendations identify areas for change that can be accomplished through individual psychiatrist action and organized group efforts
Are 90% of deaths from cancer caused by metastases?
Numerous publications have stated that metastases are responsible for 90% of cancer deaths, but data underlying this assertion has been lacking. Our objective was to determine what proportions of cancer deaths are caused by metastases. Population‐based data from the Cancer Registry of Norway for the years 2005‐2015 was analyzed. We compared all deaths in the Norwegian population where a cancer diagnosis was registered as cause of death. Deaths caused by cancer, with and without metastases, were analyzed, by sex and tumor group. For solid tumors, 66.7% of cancer deaths were registered with metastases as a contributing cause. Proportions varied substantially between tumor groups. Our data support the idea that the majority of deaths from solid tumors are caused by metastases. Thus, a better understanding of the biology of metastases and identification of druggable targets involved in growth at the metastatic site is a promising strategy to reduce cancer mortality.publishedVersio
Singlet levels of the NV centre in diamond
The characteristic transition of the NV- centre at 637 nm is between
and triplet states. There are also
intermediate and singlet states, and the
infrared transition at 1042 nm between these singlets is studied here using
uniaxial stress. The stress shift and splitting parameters are determined, and
the physical interaction giving rise to the parameters is considered within the
accepted electronic model of the centre. It is established that this
interaction for the infrared transition is due to a modification of
electron-electron Coulomb repulsion interaction. This is in contrast to the
visible 637 nm transition where shifts and splittings arise from modification
to the one-electron Coulomb interaction. It is also established that a dynamic
Jahn-Teller interaction is associated with the singlet state,
which gives rise to a vibronic level 115 above the
electronic state. Arguments associated with this level are
used to provide experimental confirmation that the is the
upper singlet level and is the lower singlet level.Comment: 19 pages, 6 figure
Summary of a Crew-Centered Flight Deck Design Philosophy for High-Speed Civil Transport (HSCT) Aircraft
Past flight deck design practices used within the U.S. commercial transport aircraft industry have been highly successful in producing safe and efficient aircraft. However, recent advances in automation have changed the way pilots operate aircraft, and these changes make it necessary to reconsider overall flight deck design. Automated systems have become more complex and numerous, and often their inner functioning is partially or fully opaque to the flight crew. Recent accidents and incidents involving autoflight system mode awareness Dornheim, 1995) are an example. This increase in complexity raises pilot concerns about the trustworthiness of automation, and makes it difficult for the crew to be aware of all the intricacies of operation that may impact safe flight. While pilots remain ultimately responsible for mission success, performance of flight deck tasks has been more widely distributed across human and automated resources. Advances in sensor and data integration technologies now make far more information available than may be prudent to present to the flight crew
Cross-over studies underestimate energy compensation:The example of sucrose-versus sucralose-containing drinks
AbstractThe vast majority of preload-test-meal studies that have investigated the effects on energy intake of disguised nutrient or other food/drink ingredient manipulations have used a cross-over design. We argue that this design may underestimate the effect of the manipulation due to carry-over effects. To test this we conducted comparable cross-over (n = 69) and parallel-groups (n = 48) studies testing the effects of sucrose versus low-calorie sweetener (sucralose) in a drink preload on test-meal energy intake. The parallel-groups study included a baseline day in which only the test meal was consumed. Energy intake in that meal was used to control for individual differences in energy intake in the analysis of the effects of sucrose versus sucralose on energy intake on the test day. Consistent with our prediction, the effect of consuming sucrose on subsequent energy intake was greater when measured in the parallel-groups study than in the cross-over study (respectively 64% versus 36% compensation for the 162 kcal difference in energy content of the sucrose and sucralose drinks). We also included a water comparison group in the parallel-groups study (n = 24) and found that test-meal energy intake did not differ significantly between the water and sucralose conditions. Together, these results confirm that consumption of sucrose in a drink reduces subsequent energy intake, but by less than the energy content of the drink, whilst drink sweetness does not increase food energy intake. Crucially, though, the studies demonstrate that study design affects estimated energy compensation
Autocatalytic plume pinch-off
A localized source of buoyancy flux in a non-reactive fluid medium creates a
plume. The flux can be provided by either heat, a compositional difference
between the fluid comprising the plume and its surroundings, or a combination
of both. For autocatalytic plumes produced by the iodate-arsenous acid
reaction, however, buoyancy is produced along the entire reacting interface
between the plume and its surroundings. Buoyancy production at the moving
interface drives fluid motion, which in turn generates flow that advects the
reaction front. As a consequence of this interplay between fluid flow and
chemical reaction, autocatalytic plumes exhibit a rich dynamics during their
ascent through the reactant medium. One of the more interesting dynamical
features is the production of an accelerating vortical plume head that in
certain cases pinches-off and detaches from the upwelling conduit. After
pinch-off, a new plume head forms in the conduit below, and this can lead to
multiple generations of plume heads for a single plume initiation. We
investigated the pinch-off process using both experimentation and simulation.
Experiments were performed using various concentrations of glycerol, in which
it was found that repeated pinch-off occurs exclusively in a specific
concentration range. Autocatalytic plume simulations revealed that pinch-off is
triggered by the appearance of accelerating flow in the plume conduit.Comment: 10 figures. Accepted for publication in Phys Rev E. See also
http://www.physics.utoronto.ca/nonlinear/papers_chemwave.htm
A Competing Values Framework for Analyzing Presentational Communication in Management Contexts
Communication specialists have long been interested in analyzing messages. More recently, they have stressed the need for evaluative tools that account for situational ex pectations and constraints. Drawing from the literature on organizational and managerial effectiveness, we constructed an empirical model applicable to presenta tional communication. Over 100 communication professors evaluated the relevance of descriptors for six different types of business presentations: three oral and three writ ten. Their judgments were used to create similarity scores, which were submitted to multidimensional scaling. A three-dimensional model emerged. This "competing values model" illustrates the dynamic interplay between the highly contrasting charac teristics of four general types of presentational communication: relational, information al, instructional, and transformational. In conclusion, we discuss the benefits of the model and suggest its usefulness as an evaluative tool, particularly for the training of managers.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/68906/2/10.1177_002194369102800303.pd
"Making Safety Happen" Through Probabilistic Risk Assessment at NASA
NASA is using Probabilistic Risk Assessment (PRA) as one of the tools in its Safety & Mission Assurance (S&MA) tool belt to identify and quantify risks associated with human spaceflight. This paper discusses some of the challenges and benefits associated with developing and using PRA for NASA human space programs. Some programs have entered operation prior to developing a PRA, while some have implemented PRA from the start of the program. It has been observed that the earlier a design change is made in the concept or design phase, the less impact it has on cost and schedule. Not finding risks until the operation phase yields much costlier design changes and major delays, which can result in discussions of just accepting the risk. Risk contributors identified by PRA are not just associated with hardware failures. They include but are not limited to crew fatality due to medical causes, the environment the vehicle and crew are exposed to, the software being used, and the reliability of the crew performing required actions. Some programs have entered operation prior to developing a PRA, and while PRA can still provide a benefit for operations and future design trades, the benefit of implementing PRA from the start of the program provides the added benefit of informing design and reducing risk early in program development. Currently, NASAs International Space Station (ISS) program is in its 20th year of on-orbit operations around the Earth and has several new programs in the design phase preparing to enter the operation phase all of which have active (or living) PRAs. These programs incorporate PRA as part of their Risk-Informed, Decision-Making (RIDM) process. For new NASA human spaceflight programs discussion begins with mission concept, establishing requirements, forming the PRA team, and continues through the design cycles into the operational phase. Several examples of PRA related applications and observed lessons are included
Natural versus forced convection in laminar starting plumes
A starting plume or jet has a well-defined, evolving head that is driven
through the surrounding quiescent fluid by a localized flux of either buoyancy
or momentum, or both. We studied the scaling and morphology of starting plumes
produced by a constant flux of buoyant fluid from a small, submerged outlet.
The plumes were laminar and spanned a wide range of plume Richardson numbers
Ri. Ri is the dimensionless ratio of the buoyancy forces to inertial effects,
and is thus our measurements crossed over the transition between
buoyancy-driven plumes and momentum-driven jets. We found that the ascent
velocity of the plume, nondimensionalized by Ri, exhibits a power law
relationship with Re, the Reynolds number of the injected fluid in the outlet
pipe. We also found that as the threshold between buoyancy-driven and
momentum-driven flow was crossed, two distinct types of plume head mophologies
existed: confined heads, produced in the Ri > 1 regime, and dispersed heads,
which are found in the Ri < 1 regime. Head dispersal is caused by a breakdown
of overturning motion in the head, and a local Kelvin-Helmholtz instability on
the exterior of the plume.Comment: 8 pages, 8 figures, accepted for publication in Physics of Fluids
(final version with corrections
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