8,502 research outputs found
Surface energy from order parameter profile: At the QCD phase transition
The order parameter profile between coexisting confined and plasma regions at the quantum chromodynamic (QCD) phase transition is constructed. The dimensionless combination of the surface energy (Sigma) and the correlation length (Zeta) is estimated to be Sigma Zeta 3 approximately equals 0.8
Identification of Cirrus over Wausau during the 1986 FIRE IFO from ground-based radiometer data
The potential of using irradiation data to indicate episodes of cirrus cloudiness during the daylight hours is explored. Thresholds separating cirrus from other clouds and clear skies are determined using four days of irradiation data, hourly weather observations, sky photographs, sky video, and occasional lidar observations. Data were gathered during the First International Satellite Cloud Climatology Program (ISCCP) Regional Experiment (FIRE) Intensive Field Observations (IFO) cirrus project. Thresholds are tested using data from the remaining 17 days of the IFO. Cirrus episodes are defined as intervals when the sky cover is primarily cirrus. Measurements of incoming shortwave and near infrared full hemispheric and diffuse irradiation, and atmospheric infrared irradiation were made at Wausau, Wisconsin Municipal Airport. Data were collected between October 13 and November 2, 1986 and are one minute averages of ten second samples. Data from October 23 and from October 27 to 29 were used for threshold determination. Using weather observations, lidar output, photographs and video, sky conditions were grouped into three categories: noncirrus cloudy, cirrus, and clear. Irradiation data from all periods falling under each of the sky categories were then examined and thresholds denoting a change from one sky category to another were determined. Variables with only a small amount of overlap between sky categories were selected as key indicators
FIRE extended time/limited area observations at Palisades, New York
Downwelling shortwave and longwave irradiation are being continuously monitored at Palisades, New York as part of the First International Satellite Cloud Climatology Project (ISCCP) Regional Experiment (FIRE) Extended Time/Limited Area Initiative. In addition, fisheye (180 degree) sky photographs are taken at the times of NOAA 9 and LANDSAT satellite overpasses on select days, particularly when cirrus clouds are present. Measurements of incoming shortwave (0.28 to 2.80 microns) hemispheric and diffuse, hemispheric near infrared (0.7 to 2.80 microns), and downwelling hemispheric infrared (4.0 to 50.0 microns) irradiation have been made from a rooftop location on the grounds of the Lamont-Doherty Geological Observatory since December 1986. The three Eppley Precision Spectral Pyranometers and the Eppley Pyrgeometer used to measure these variables were calibrated with Colorado State University instruments at Madison, Wisconsin as part of the FIRE Intensive Laboratory. Pyrgeometer output contains an adjustment for body temperature but not for dome temperature. Data are transmitted to a Campbell CR-21 Digital Recorder, where one minute averages of ten second samples are stored and subsequently dumped to a cassette recorder. Using a Campbell C-20 Cassette Interface, these data are transferred to an Apple Macintosh computer for analysis and for archiving on floppy disks. In addition to the raw irradiances collected, variables derived from these data are generated and stored. These include: the ratio of near infrared irradiation to visible irradiation and the fraction of the full shortwave irradiation which is diffuse; and will soon include: shortwave transmissivity and optical depth in the shortwave. Sky photographs are taken with an Olympus OM2-N 35 mm camera and are timed to be coincident with overpassing NOAA and LANDSAT satellites. Palisades is within the field of view of the NOAA 9 daily in the middle to late afternoon. The satellite viewing angle is within 45 degrees of nadir over Palisades on approximately half of the passes
Impact of cirrus on the surface radiative environment at the FIRE ETLA Palisades, NY site
FIRE Extended Time Limited Area (ETLA) observations provide year round information critical to gaining a better understanding of cloud/climate interactions. The Lamont/Rutgers team has participated in the ETLS program through the collection and analysis of shortwave and longwave downwelling irradiances at Palisades, NY. These data are providing useful information on surface radiative fluxes with respect to sky condition, solar zenith angle and season. Their utility extends to the calibration and validation of cloud/radiative models and satellite cloud and radiative retrievals. The impact cirrus clouds have on the surface radiative environment is examined using Palisades ETLA information on atmospheric transmissivities and downwelling longwave fluxes for winter and summer cirrus and clear sky episodes in 1987
An information states blackboard as an intelligent querying interface for snow and avalanche data
We present the graph-based querying paradigm used in the Regional Avalanche Information and Forecasting System (RAIFoS) for the collection and analysis of snow and weather related physical parameters in the Swiss Alps. The querying paradigm relies upon the issue of interactively
constructing a semantically valid query graph on an Information States Blackboard as guided by meta-data elements standing for interpretations of conceptual model, data values and/or operations. The meta-data elements constitute the terms of a meta-data-driven query language
(MDDQL) the interpretation of which is done interactively relying on a kind of finite state automaton
Unkooperatives Kind bei Narkoseeinleitung: Theorie und Praxis
Zusammenfassung: Perioperative Angst und daraus resultierende mangelnde Kooperation bei der Narkoseeinleitung sind ein häufiges Problem in der Kinderanästhesie. Das Ausmaß der Angst hängt von verschiedenen kindlichen, aber auch von elterlichen Faktoren, dem Anästhesieteam sowie der kinderfreundlichen Atmosphäre und Infrastruktur des Krankenhauses ab. Neben einer Prämedikation gibt es verschiedene nichtpharmakologische Maßnahmen, um die kindliche Angst zu reduzieren und damit die Narkoseeinleitung zu erleichtern. Bleibt das Kind trotz aller vorbereitenden Maßnahmen weiterhin unkooperativ, muss grundsätzlich unter Berücksichtigung verschiedener Kriterien entschieden werden, ob der Eingriff, falls medizinisch vertretbar, verschoben wird oder ob die Narkoseeinleitung unter Anwendung von körperlichem Zwang durchgeführt werden sol
Rotordynamic coefficients and leakage flow of parallel grooved seals and smooth seals
Based on Childs finite length solution for annular plain seals an extension of the bulk flow theory is derived to calculate the rotordynamic coefficients and the leakage flow of seals with parallel grooves in the stator. Hirs turbulent lubricant equations are modified to account for the different friction factors in circumferential and axial direction. Furthermore an average groove depth is introduced to consider the additional circumferential flow in the grooves. Theoretical and experimental results are compared for the smooth constant clearance seal and the corresponding seal with parallel grooves. Compared to the smooth seal the direct and cross-coupled stiffness coefficients as well as the direct damping coefficients are lower in the grooved seal configuration. Leakage is reduced by the grooving pattern
Drosophila Cyclin D/Cdk4 Requires Hif-1 Prolyl Hydroxylase to Drive Cell Growth
AbstractThe Drosophila cyclin-dependent protein kinase complex Cyclin D/Cdk4 induces cell growth (accumulation of mass) as well as proliferation (cell cycle progression). To understand how CycD/Cdk4 promotes growth, we performed a screen for modifiers of CycD/Cdk4-driven overgrowth in the eye. Loss-of-function mutations in Hif-1 prolyl hydroxylase (Hph), an enzyme involved in the cellular response to hypoxic stress, dominantly suppress the growth but not the proliferation function of CycD/Cdk4. hph mutant cells are defective for growth, and, remarkably, ectopic expression of Hph is sufficient to increase cellular growth. Epistasis analysis places Hph downstream of CycD/Cdk4. Overexpressed CycD/Cdk4 causes an increase in Hph protein in tissues where Hph induces growth, suggesting a mechanism whereby Hph levels are regulated posttranscriptionally in response to CycD/Cdk4. Our data suggest that Hph, in addition to its function in hypoxic response, is a regulator of cellular growth and that it is a key mediator for CycD/Cdk4
Complete Wetting of Gluons and Gluinos
Complete wetting is a universal phenomenon associated with interfaces
separating coexisting phases. For example, in the pure gluon theory, at
an interface separating two distinct high-temperature deconfined phases splits
into two confined-deconfined interfaces with a complete wetting layer of
confined phase between them. In supersymmetric Yang-Mills theory, distinct
confined phases may coexist with a Coulomb phase at zero temperature. In that
case, the Coulomb phase may completely wet a confined-confined interface.
Finally, at the high-temperature phase transition of gluons and gluinos,
confined-confined interfaces are completely wet by the deconfined phase, and
similarly, deconfined-deconfined interfaces are completely wet by the confined
phase. For these various cases, we determine the interface profiles and the
corresponding complete wetting critical exponents. The exponents depend on the
range of the interface interactions and agree with those of corresponding
condensed matter systems.Comment: 15 pages, 5 figure
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