Investigations into the burning-out of organic substances in the ceramic body

Pressed compacts were made of spray dried alumina containing water soluble polyvinyl alcohol or cellulose derivative binder. The burning out of organic binder on gradual heating was investigated by visual and microscopic observations of the cross section and by thermogravimetry. Burning out proceeds inward from the peripheries, gradually reducing the size of the black core, which first consists of a dark boundary layer and later turns uniformly black with a sharp boundary. A detailed mechanism of the burning out process between and within the spray dried granules is observed under the microscope. Oxygen atmosphere accelerates the burning out process

Temporal Change Enhancement in Multispectral Images Remotely Sensed from Satellites

The application of principal components analysis to multispectral satellite images is a routine way to present the data in false-color composite images. These composite images include a very high percentage of available information and have no correlation between the displayed colors. The transformation of multispectral image data into its principal components is also an effective way to separate image information from noise. This paper describes a procedure for temporal change enhancement which exploits both the decorrelation and noise isolation properties of the principal components transformation. Using simulated temporal change, this procedure was demonstrated to be more effective than the standard procedures described in the literature. Simulated temporal change as low as one percent of original pixel brightness was easily seen. Changes of less than one percent were difficult to simulate because of integer roundoff. However, a one percent change was sufficient to measure the relative effectiveness of each procedure considered

Tropical Forest Protection, Uncertainty, and the Environmental Integrity of Carbon Mitigation Policies

Tropical forests are estimated to release approximately 1.7 PgC per year as a result of deforestation. Avoiding tropical deforestation could potentially play a significant role in carbon mitigation over the next 50 years if not longer. Many policymakers and negotiators are skeptical of our ability to reduce deforestation effectively. They fear that if credits for avoided deforestation are allowed to replace fossil fuel emission reductions for compliance with Kyoto, the environment will suffer because the credits will not reflect truly additional carbon storage. This paper considers the nature of the uncertainties involved in estimating carbon stocks and predicting deforestation. We build an empirically based stochastic model that combines data from field ecology, geographical information system (GIS) data from satellite imagery, economic analysis and ecological process modeling to simulate the effects of these uncertainties on the environmental integrity of credits for avoided deforestation. We find that land use change, and hence additionality of carbon, is extremely hard to predict accurately and errors in the numbers of credits given for avoiding deforestation are likely to be very large. We also find that errors in estimation of carbon storage could be large and could have significant impacts. We find that in Costa Rica, nearly 42% of all the loss of environmental integrity that would arise from poor carbon estimates arises in one life zone, tropical wet. This suggests that research effort might be focused in this life zone.climate, economics, carbon sequestration, uncertainty, policy, tropics

Carbon Dynamics and Land-Use Choices: Building a Regional-Scale Multidisciplinary Model

Policy enabling tropical forests to approach their potential contribution to global-climate-change mitigation requires forecasts of land use and carbon storage on a large scale over long periods. In this paper, we present an integrated modeling methodology that addresses these needs. We model the dynamics of the human land-use system and of C pools contained in each ecosystem, as well as their interactions. The model is national scale, and is currently applied in a preliminary way to Costa Rica using data spanning a period of over fifty years. It combines an ecological process model, parameterized using field and other data, with an economic model, estimated using historical data to ensure a close link to actual behavior. These two models are linked so that ecological conditions affect land-use choices and vice versa. The integrated model predicts land use and its consequences for C storage for policy scenarios. These predictions can be used to create baselines, reward sequestration, and estimate the value in both environmental and economic terms of including C sequestration in tropical forests as part of the efforts to mitigate global climate change. The model can also be used to assess the benefits from costly activities to increase accuracy and thus reduce errors and their societal costs.carbon, sequestration, climate change, land use, modelling

Polar observations of electron density distribution in the Earth's magnetosphere. 2. Density profiles

International audienceUsing spacecraft potential measurements of the Polar electric field experiment, we investigate electron density variations of key plasma regions within the magnetosphere, including the polar cap, cusp, trough, plasmapause, and auroral zone. The statistical results were presented in the first part of this study, and the present paper reports detailed structures revealed by individual satellite passes. The high-altitude (> 3 RE) polar cap is generally one of the most tenuous regions in the magnetosphere, but surprisingly, the polar cap boundary does not appear as a steep density decline. At low altitudes (1 RE) in summer, the polar densities are very high, several 100 cm-3 , and interestingly, the density peaks at the central polar cap. On the noonside of the polar cap, the cusp appears as a dense, 1?3° wide region. A typical cusp density above 4 RE distance is between several 10 cm-3 and a few 100 cm-3 . On some occasions the cusp is crossed multiple times in a single pass, simultaneously with the occurrence of IMF excursions, as the cusp can instantly shift its position under varying solar wind conditions, similar to the magnetopause. On the nightside, the auroral zone is not always detected as a simple density cavity. Cavities are observed but their locations, strengths, and sizes vary. Also, the electric field perturbations do not necessarily overlap with the cavities: there are cavities with no field disturbances, as well as electric field disturbances observed with no clear cavitation. In the inner magnetosphere, the density distributions clearly show that the plasmapause and trough densities are well correlated with geomagnetic activity. Data from individual orbits near noon and midnight demonstrate that at the beginning of geomagnetic disturbances, the retreat speed of the plasmapause can be one L-shell per hour, while during quiet intervals the plasmapause can expand anti-earthward at the same speed. For the trough region, it is found that the density tends to be an order of magnitude higher on the day-side (~1 cm-3) than on the nightside (~0.1?1 cm-3), particularly during low Kp

Polar observations of electron density distribution in the Earth's magnetosphere. 1. Statistical results

International audienceForty-five months of continuous spacecraft potential measurements from the Polar satellite are used to study the average electron density in the magnetosphere and its dependence on geomagnetic activity and season. These measurements offer a straightforward, passive method for monitoring the total electron density in the magnetosphere, with high time resolution and a density range that covers many orders of magnitude. Within its polar orbit with geocentric perigee and apogee of 1.8 and 9.0 RE, respectively, Polar encounters a number of key plasma regions of the magnetosphere, such as the polar cap, cusp, plasmapause, and auroral zone that are clearly identified in the statistical averages presented here. The polar cap density behaves quite systematically with season. At low distance (~2 RE), the density is an order of magnitude higher in summer than in winter; at high distance (>4 RE), the variation is somewhat smaller. Along a magnetic field line the density declines between these two altitudes by a factor of 10?20 in winter and by a factor of 200?1000 in summer. A likely explanation for the large gradient in the summer is a high density of heavy ions that are gravitationally bound in the low-altitude polar cap. The geomagnetic effects are also significant in the polar cap, with the average density being an order of magnitude larger for high Kp; for an individual case, the polar cap density may increase even more dramatically. The plasma density in the cusp is controlled primarily by the solar wind variables, but nevertheless, they can be characterized to some extent in terms of the Kp index. We also investigate the local time variation of the average density at the geosynchronous distance that appears to be in accordance with previous geostationary observations. The average density decreases with increasing Kp at all MLT sectors, except at 14?17 MLT, where the average density remains constant. At all MLT sectors the range of the density varies by more than 3 orders of magnitude, since the geostationary orbit may cut through different plasma regions, such as the plasma sheet, trough, and plasmasphere

Malpractice Cases in Wound Care and a Legal Concept: Special Defense

There is no doubt that in today’s practice of emergency medicine it is imperative to be familiar with how the law relates to administrative and clinical practice. It is my pleasure to announce, as section editor, the new Legal Medicine section of the Western Journal of Emergency Medicine. It is anticipated that the articles will cover a variety of areas and cases in the law. Some articles may focus on a particular disease or entity, with representative malpractice cases, and clinical caveats. Other articles may focus on legal concepts that enter the arena of emergency medicine. I have provided brief examples of each of these in this initial manuscript. Other articles could also cover original research related to law such as the standard of care in a given clinical situation or legal concepts such as consent, do-not-resuscitate, and AMA among others. I am hopeful that it will be of great interest to the readers. We welcome submissions and contributions for consideration

Striking the Balance: US Army Force Posture in Europe, 2028—A Study Sponsored by the Office of the Secretary of the Army

Within the context of Europe, the US Army must develop a force posture that best navigates the tensions between deterring or defeating armed conflict at an acceptable cost, successfully competing below armed conflict, and maintaining global responsiveness and institutional flexibility through the global operating model and dynamic force employment. While Russia’s economy, and consequently military capability will likely shrink over the next 10 years, which can make them more dangerous as the Kremlin continues to try to punch above its weight. The ideal force posture needs to accomplish a range of on-going and contingency missions and also be adaptive enough to remain viable despite any number of potential swings in resources, military balance, or the domestic politics of allies. This study recommends five possible strategic approaches and specifies what conditions and priorities optimize each. The principal investigators recommend investing in a multidomain alliance. This strategic approach enables the joint force and multinational partners to get the most of their capabilities and makes the best use of the Army’s top modernization priorities, such as long-range fires in a way that alters the strategic balance of a theater to avert a potentially catastrophic, albeit low probability, scenario of armed conflict. More importantly, this strategic approach is far more stable in a crisis, as it does not place policymakers in having to rush this critical, escalatory capability into theater at a moment of high tension. Moreover, invest in a multidomain alliance has the flexibility to allow a later build-up of heavy forces if conditions still warrant.https://press.armywarcollege.edu/monographs/1906/thumbnail.jp

VLF and HF Plasma Waves Associated with Spread-F Plasma Depletions Observed on the C/NOFS Satellite

The C/NOFS spacecraft frequently encounters structured plasma depletions associated with equatorial spread-F along its trajectory that varies between 401 km perigee and 867 km apogee in the low latitude ionosphere. We report two classes of plasma waves detected with the Vector Electric Field Investigation (VEFI) that appear when the plasma frequency is less than the electron gyro frequency, as is common in spread-F depletions where the plasma number density typically decreases below 10(exp 4)/cu cm. In these conditions, both broadband VLF waves with a clear cutoff at the lower hybrid frequency and broadband HF waves with a clear cutoff at the plasma frequency are observed. We interpret these waves as "hiss-type" emissions possibly associated with the flow of suprathermal electrons within the inter-hemispherical magnetic flux tubes. We also report evidence of enhanced wave "transients" sometimes embedded in the broader band emissions that are associated with lightning sferics detected within the depleted plasma regions that appear in both the VLF and HF data. Theoretical implications of these observations are discussed

Revealing charge-tunneling processes between a quantum dot and a superconducting island through gate sensing

We report direct detection of charge-tunneling between a quantum dot and a superconducting island through radio-frequency gate sensing. We are able to resolve spin-dependent quasiparticle tunneling as well as two-particle tunneling involving Cooper pairs. The quantum dot can act as an RF-only sensor to characterize the superconductor addition spectrum, enabling us to access subgap states without transport. Our results provide guidance for future dispersive parity measurements of Majorana modes, which can be realized by detecting the parity-dependent tunneling between dots and islands.Comment: 6 pages, 4 figures, supplemental material included as ancillary fil