68,958 research outputs found
Fluid quality in a self-pressurized container discharge line
Quality of cryogenic fluids in vertical discharge line during draining of saturated liquid from self-pressurized containe
Primitive erythropoiesis in early chick embryogenesis. II. Correlation between hemoglobin synthesis and the mitotic history.
Primitive erythroblasts in the circulating blood of the chick embryo continue to divide while synthesizing hemoglobin (Hb). Hb measurements on successive generations of erythroblasts show that there is a progressive increase in the Hb content of both interphase and metaphase cells. Furthermore, for any given embryo the Hb content of metaphase cells is always significantly greater than that of interphase cells. The distribution of Hb values for metaphase cells suggests that there are six Hb classes corresponding to the number of cell cycles in the proliferative phase. The location of erythroblasts in the cell cycle was determined by combining Feulgen cytophotometry with thymidine radioautography on the same cells. Measurements of the Hb content for erythroblasts in different compartments of the cell cycle (G1, S, G2, and M) show a progressive increase through the cycle. Thus, the amount of Hb per cell is a function of the number of cell divisions since the initiation of Hb synthesis and, to a lesser degree, the stage of the cell cycle. Earlier generations of erythroblasts synthesize Hb at a faster rate than the terminal generation. Several models have been proposed to explain these findings
Teleporting bipartite entanglement using maximally entangled mixed channels
The ability to teleport entanglement through maximally entangled mixed states
as defined by concurrence and linear entropy is studied. We show how the
teleported entanglement depends on the quality of the quantum channel used, as
defined through its entanglement and mixedness, as well as the form of the
target state to be teleported. We present new results based on the fidelity of
the teleported state as well as an experimental set-up that is immediately
implementable with currently available technology.Comment: 8 pages, 7 figures, RevTeX4, Accepted for publication in the IJQI
special issue on Distributed Quantum Information Processin
Field Effect Transistors on Rubrene Single Crystals with Parylene Gate Insulator
We report on fabrication and characterization of the organic field effect
transistors (OFETs) on the surface of single crystals of rubrene. The parylene
polymer film has been used as the gate insulator. At room temperature, these
OFETs exhibit the p-type conductivity with the field effect mobility up to 1
cm^2/Vs and the on/off ratio ~ 10^4. The temperature dependence of the mobility
is discussed.Comment: 3 page
The credibility of health economic models for health policy decision-making: the case of population screening for abdominal aortic aneurysm
<i>Objectives</i>: To review health economic models of population screening for abdominal aortic aneurysm (AAA) among elderly males and assess their credibility for informing decision-making.
<i>Methods</i>: A literature review identified health economic models of ultrasound screening for AAA. For each model focussing on population screening in elderly males, model structure and input parameter values were critically appraised using published good practice guidelines for decision analytic models.
<i>Results</i>: Twelve models published between 1989 and 2003 were identified. Converting costs to a common currency and base year, substantial variability in cost-effectiveness results were revealed. Appraisals carried out for the nine models focusing on population screening showed differences in their complexity, with the simpler models generating results most favourable to screening. Eight of the nine models incorporated two or more simplifying structural assumptions favouring screening; uncertainty surrounding these assumptions was not investigated by any model. Quality assessments on a small number of parameters revealed input values varied between models, methods used to identify and incorporate input data were often not described, and few sensitivity analyses were reported.
<i>Conclusions</i>: Large variation exists in the cost-effectiveness results generated by AAA screening models. The substantial number of factors potentially contributing to such disparities means that reconciliation of model results is impossible. In addition, poor reporting of methods makes it difficult to identify the most plausible and thus most useful model of those developed
Does the Sun shrink with increasing magnetic activity?
It has been demonstrated that frequencies of f-modes can be used to estimate
the solar radius to a good accuracy. These frequencies have been used to study
temporal variations in the solar radius with conflicting results. The variation
in f-mode frequencies is more complicated than what is assumed in these
studies. If a careful analysis is performed then it turns out that there is no
evidence for any variation in the solar radius.Comment: To appear in Astrophys.
The Scaling Mindset â Shifting from Problems to Solutions. Insights from the Review of CCAFS Scaling Activities, 2019
In the frame of the review of CCAFS scaling activities in 2019, 21 project leaders and âimplementers were interviewed about their scaling processes, touching a series of aspects that had been identified as crucial and/or critical by earlier research. Results were analysed with a systemic approach, to draw organisational learnings. The findings were validated with CCAFS core team during their Scaling Workshop in Madrid, May 2019, in which the Core Team also prioritized its programmatic areas of response.
This working paper captures the main insights and learnings from both the interviews on project level, followed by the resultsâ analysis. It then summarized the Core Team workshopâs main discussion points and shortly outlines the programmatic areas of response that CCAFS identified.
The learnings and insights on the realities of scaling agricultural innovations presented in this working paper can provide a rich basis for further synthesis and/or deeper research on the different aspects of innovation development and scaling
Electrophoretic deposition of gradated oxidation resistant coatings on tantalum-10 tungsten alloy
Material selection and electrophoretic deposition studies of high temperature oxidation resistant coatings on tantalum-10 tungsten allo
Development of oxidation resistant coatings for use above 3500 deg F
Physical property evaluation of oxidation resistant coating materials for high temperature protection of tantalum-base alloy
Groundwater characteristics at Seabee Hook, Cape Hallett, Antarctica
Seabee Hook is a low lying gravel spit adjacent to Cape Hallett, northern Victoria Land, in the Ross Sea region of Antarctica and hosts an AdĂŠlie penguin (Pygoscelis adeliae) rookery. Dipwells were inserted to monitor changes in depth to, and volume of, groundwater and tracer tests were conducted to estimate aquifer hydraulic conductivity and groundwater velocity. During summer (NovemberâFebruary), meltwater forms a shallow, unconfined, aquifer perched on impermeable ice cemented soil. Groundwater extent and volume depends on the amount of snowfall as meltwater is primarily sourced from melting snow drifts. Groundwater velocity through the permeable gravel and sand was up to 7.8 m dayâ1, and hydraulic conductivities of 4.7 Ă 10â4 m sâ1 to 3.7 Ă 10â5 m sâ1 were measured. The presence of the penguin rookery, and the proximity of the sea, affects groundwater chemistry with elevated concentrations of salts (1205 mg Lâ1 sodium, 332 mg Lâ1 potassium) and nutrients (193 mg Lâ1 nitrate, 833 mg Lâ1 ammonia, 10 mg Lâ1 total phosphorus) compared with groundwater sourced away from the rookery, and with other terrestrial waters in Antarctica
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