bluuebunny/crossref_metadata_2025_split huggingface dataset:
Continental Passive Microwave-Based Rainfall Estimation Algorithm: Application to the Amazon Basin
Authors: Biscaro Thiago S. , Morales Carlos A. 
Published: July 2008

AbstractThis paper presents a new statistical algorithm to estimate rainfall over the Amazon Basin region using the Tropical Rainfall Measuring Mission (TRMM) Microwave Imager (TMI). The algorithm relies on empirical relationships derived for different raining-type systems between coincident measurements of surface rainfall rate and 85-GHz polarization-corrected brightness temperature as observed by the precipitation radar (PR) and TMI on board the TRMM satellite. The scheme includes rain/no-rain area delineation (screening) and system-type classification routines for rain retrieval. The algorithm is validated against independent measurements of the TRMM–PR and S-band dual-polarization Doppler radar (S-Pol) surface rainfall data for two different periods. Moreover, the performance of this rainfall estimation technique is evaluated against well-known methods, namely, the TRMM-2A12 [the Goddard profiling algorithm (GPROF)], the Goddard scattering algorithm (GSCAT), and the National Environmental Satellite, Data, and Information Service (NESDIS) algorithms. The proposed algorithm shows a normalized bias of approximately 23% for both PR and S-Pol ground truth datasets and a mean error of 0.244 mm h−1 (PR) and −0.157 mm h−1 (S-Pol). For rain volume estimates using PR as reference, a correlation coefficient of 0.939 and a normalized bias of 0.039 were found. With respect to rainfall distributions and rain area comparisons, the results showed that the formulation proposed is efficient and compatible with the physics and dynamics of the observed systems over the area of interest. The performance of the other algorithms showed that GSCAT presented low normalized bias for rain areas and rain volume [0.346 (PR) and 0.361 (S-Pol)], and GPROF showed rainfall distribution similar to that of the PR and S-Pol but with a bimodal distribution. Last, the five algorithms were evaluated during the TRMM–Large-Scale Biosphere–Atmosphere Experiment in Amazonia (LBA) 1999 field campaign to verify the precipitation characteristics observed during the easterly and westerly Amazon wind flow regimes. The proposed algorithm presented a cumulative rainfall distribution similar to the observations during the easterly regime, but it underestimated for the westerly period for rainfall rates above 5 mm h−1. NESDIS1 overestimated for both wind regimes but presented the best westerly representation. NESDIS2, GSCAT, and GPROF underestimated in both regimes, but GPROF was closer to the observations during the easterly flow.
Radar Measurement of Rainfall with and without Polarimetry
Authors: Ulbrich Carlton W. , Atlas David 
Published: July 2008

Abstract
Raindrop size distributions (DSDs) for tropical convective storms are used to examine the relationships between the parameters of a gamma DSD, with special emphasis on their variation with the stage of the storm. Such a distinction has rarely been made before. Several storms from a variety of tropical locations are divided into storm stages according to the temporal dependence of their reflectivity factor Z, rainfall rate R, and median volume diameter D0. In most cases it is found that the DSD parameter D0 is approximately constant in time during the convective, or C, stage, which leads to a Z–R relation of the form Z = AR, that is, a linear relationship between Z and R. This finding implies the existence of equilibrium DSDs during the C stage. The convective stage is sometimes marked by pulsations in draft strength so that D0, R, and Z and associated values of the shape parameter μ decrease in a quasi-transition stage before increasing once more. Theoretical relations between the differential reflectivity ZDR and the ratio Z/R as functions of the DSD parameter μ are derived by assuming a gamma DSD and an accurate raindrop fall speed law. It is found that data derived from disdrometer observations lie along a μ = 5 isopleth for tropical continental C stages (Puerto Rico and Brazil) and along a μ = 12 isopleth for tropical maritime C stages [Tropical Ocean and Global Atmosphere Coupled Ocean–Atmosphere Response Experiment (TOGA COARE)]. Small values of μ that occur in the weak updraft intervals do not impact the rainfall measurements because they correspond to relatively small R. The latter features imply that the measurement of rainfall for the convective stages can be performed with standard polarimetry involving only two measurables rather than three, provided knowledge of μ is available a priori. A new rain parameter diagram is presented in which isopleths of the generalized number concentration and D0 are superimposed on the Z–R plot. It is proposed that it is possible to estimate D0 from climatological and observable storm structural features, which, with Z, provide estimates of R. Such an approach is necessary for use with conventional radars until polarimetric radars are more widely available.
Physical Modeling of Flow Field inside Urban Street Canyons
Authors: Li Xian-Xiang , Leung Dennis Y. C. , Liu Chun-Ho , Lam K. M. 
Published: July 2008

Abstract
The flow characteristics inside urban street canyons were studied in a laboratory water channel. The approaching flow direction was horizontal and perpendicular to the street axis. The street width was adjusted to form street canyons of aspect ratios 0.5, 1.0, and 2.0. The velocity field and turbulent intensity were measured with a laser Doppler anemometer at various locations within the street canyons, which were used to elucidate the flow pattern inside the street canyons. It was found that the previous numerical modeling results are in good agreement with the current experimental results at most locations. For the street canyon of aspect ratio 0.5, which belongs to the wake interference flow regime, the mean and fluctuating velocity components were more difficult to measure as compared with the other two cases because of its more complicated flow pattern. Some guidelines for numerical modeling were developed based on the measurement results. The data presented in this paper can also be used as a comprehensive database for the validation of numerical models.
On the Role of Snow Cover in Depressing Air Temperature
Authors: Mote Thomas L. 
Published: July 2008

Abstract
This study empirically examines the role of snow depth on the depression of air temperature after controlling for effect of temperature changes above the boundary layer. In addition, this study examines the role of cloud cover, solar elevation angle, and maximum snow-covered albedo on the temperature depression due to snow cover. The work uses a new dataset of daily, gridded snow depth, snowfall, and maximum and minimum temperatures for North America from 1960 to 2000 in conjunction with 850-hPa temperature data for the same period from the NCEP–NCAR reanalysis, version 1. The 850-hPa temperatures are used as a control to remove the effect of temperature changes above the boundary layer on surface air temperatures. Findings from an analysis of variance demonstrate that snow cover can result in daily maximum (minimum) temperature depressions on average of 4.5°C (2.6°C) for snow depths greater than 10 cm over the grasslands of central North America, but temperature depressions average only 1.2°C (1.1°C) overall. The temperature depression of snow cover is shown to be reduced by increased cloud cover and decreased maximum albedo, which is indicative of denser forest cover. The role of snow melting on temperature depression is further explored by comparing days with maximum temperatures above or below freezing.
On the Dynamics of the Slope Current System along the West European Margin. Part I: Analytical Calculations and Numerical Simulations with Steady-State Forcing
Authors: Friocourt Yann , Drijfhout Sybren , Blanke Bruno 
Published: July 2008

Abstract
The dynamics of the baroclinic slope current system along the western European margin in the Bay of Biscay and along the northern Iberian Peninsula are investigated in two different models, one analytical and one numerical. Investigated here is the hypothesis that the steady-state slope current system is driven by the large-scale meridional density gradients. An analysis of the observed density fields evidences a four-layer structure with meridional gradients of alternate signs, which is also found in the numerical model. The linear analytical model of the continental margin shows that such a density structure is enough to obtain a steady-state four-layer slope current system comparable to the observed annual mean circulation. The slope currents result from a balance between bottom friction and meridional density gradients. The numerical simulation with an ocean general circulation model forced only by the large-scale density gradients at the lateral boundaries presents a four-layer slope current system similar to the circulation obtained in the analytical model. The study confirms that the large-scale meridional density gradients are the main driving mechanism for the steady-state slope current system; the large seasonality of these currents, however, requires a more extended model, which is discussed in a companion paper (Part II).
Rapidly Intensifying Hurricane Guillermo (1997). Part I: Low-Wavenumber Structure and Evolution
Authors: Reasor Paul D. , Eastin Matthew D. , Gamache John F. 
Published: July 2008

Abstract
The structure and evolution of rapidly intensifying Hurricane Guillermo (1997) is examined using airborne Doppler radar observations. In this first part, the low-azimuthal-wavenumber component of the vortex is presented. Guillermo’s intensification occurred in an environmental flow with 7–8 m s−1 of deep-layer vertical shear. As a consequence of the persistent vertical shear forcing of the vortex, convection was observed primarily in the downshear left quadrant of the storm. The greatest intensification during the ∼6-h Doppler observation period coincided with the formation and cyclonic rotation of several particularly strong convective bursts through the left-of-shear semicircle of the eyewall. Some of the strongest convective bursts were triggered by azimuthally propagating low-wavenumber vorticity asymmetries. Mesoscale budget analyses of axisymmetric angular momentum and relative vorticity within the eyewall are presented to elucidate the mechanisms contributing to Guillermo’s structural evolution during this period. The observations support a developing conceptual model of the rapidly intensifying, vertically sheared hurricane in which shear-forced mesoscale ascent in the downshear eyewall is modulated by internally generated vorticity asymmetries yielding episodes of anomalous intensification.
A Comparison of the Atmospheric Response to ENSO in Coupled and Uncoupled Model Simulations
Authors: Jha Bhaskar , Kumar Arun 
Published: July 2008

Abstract
In the Atmospheric Model Intercomparison Project (AMIP) simulations the sea surface temperatures (SSTs) are specified and the oceanic evolution consistent with air–sea interaction is not included. This omission could lead to errors in the atmospheric response to SSTs. At the same time, the AMIP experimental setup is well suited for investigating many aspects of climate variability (e.g., the attribution of the interannual atmospheric variability) and continues to be extensively used. As coupled El Niño–Southern Oscillation (ENSO) SST variability is a dominant factor in determining the predictable component of the observed interannual atmospheric variability, the difference in the atmospheric response to ENSO SSTs between AMIP and coupled simulations is investigated. The results indicate that the seasonal atmospheric response to ENSO between coupled and uncoupled integrations is similar, and the inclusion of oceanic evolution consistent with air–sea interaction does not play a dominant role. The analysis presented in this paper is one step toward assessing differences in atmospheric response to SSTs in coupled and uncoupled simulations, and is required to correctly interpret the results of AMIP simulations.
Contributions of Convectively Coupled Equatorial Rossby Waves and Kelvin Waves to the Real-Time Multivariate MJO Indices
Authors: Roundy Paul E. , Schreck Carl J. , Janiga Matthew A. 
Published: July 2008

Abstract
The real-time multivariate (RMM) Madden–Julian oscillation (MJO) indices have been widely applied to diagnose and track the progression of the MJO. Although it has been well demonstrated that the MJO contributes to the leading signals in these indices, the RMM indices vary erratically from day to day. These variations are associated with noise in the outgoing longwave radiation (OLR) and wind data used to generate the indices. This note demonstrates that some of this “noise” evolves systematically and is associated with other types of propagating modes that project onto the RMM eigenmodes. OLR and zonal wind data are filtered in the wavenumber–frequency domain for the MJO, convectively coupled equatorial Rossby (ER) waves, and convectively coupled Kelvin waves. The filtered data are then projected onto the RMM modes. An example phase space associated with these projections is presented. Linear regression is then applied to isolate the wave signals from random variations in the same bands of the wavenumber–frequency domain, and the regressed data are projected onto the RMM EOFs. Results demonstrate the magnitudes of the contributions of the systematically evolving signals associated with these waves to variations in the RMM principal components, and how these contributions vary with the longitude of the active moist deep convection coupled to the waves.
Correlation between DJ-1 levels in the cerebrospinal fluid and the progression of disabilities in multiple sclerosis patients
Authors: Hirotani M , Maita C , Niino M , Iguchi-Ariga SM , Hamada S , Ariga H , Sasaki H 
Published: July 2008

Objectives DJ-1 plays a key role in the anti-oxidative stress function. Increasing evidence supports the role of oxidative stress in the pathogenesis of multiple sclerosis (MS). The aim of this study was to investigate whether the DJ-1 levels were increased in patients with MS and to examine its association with the progression of MS. Methods Quantitative immunoblot assays were performed to evaluate the DJ-1 level in serum and cerebrospinal fluid (CSF) collected from relapsing–remitting patients with MS ( n = 29), disease controls subjects ( n = 14), and healthy subjects ( n = 44). Results No significant difference was observed in the serum DJ-1 level among the patients with MS, disease controls, and healthy controls. However, the CSF DJ-1 levels were significantly higher in the patients with MS than in the disease control subjects ( P < 0.0001). A significant positive correlation was also found between the CSF DJ-1 levels and the Multiple Sclerosis Severity Score ( P < 0.005, r = 0.501). Conclusions These results show that the CSF DJ-1 levels are significantly increased in the CSF of patients with MS and that the CSF DJ-1 levels may be associated with the disease progression of MS. Therefore, DJ-1 possibly plays an important role in the pathogenesis of MS.
Canadian treatment optimization recommendations (TOR) as a predictor of disease breakthrough in patients with multiple sclerosis treated with interferon β-1a: analysis of the PRISMS study
Authors: Freedman MS , Forrestal FG 
Published: July 2008

BackgroundEarly intervention with an effective disease-modifying drug (DMD) offers the best chance of limiting the inflammatory process that contributes to irreversible axonal damage correlating with disability in multiple sclerosis (MS). It is equally important to ascertain fairly quickly whether patients are responding positively to the choice of therapy to allow time for either a treatment modification or a switch in treatment, a process we termed “treatment optimization”. Various treatment optimization recommendations (TOR) have been proposed to help decide when a patient taking an MS DMD might be showing a sub-optimal response. We have applied the clinical scheme proposed by the Canadian TOR to the patients involved in the Prevention of Relapses and disability by Interferon Subcutaneously in MS 4-year (PRISMS-4) study, who received interferon β-1a treatment for 4 years, with the TOR applied retrospectively at year 1.ObjectiveThe aim of this investigation was to examine whether these TOR were able to predict which patients would go on to develop disease breakthrough (defined as any relapses or disease progression), indicative of a sub-optimal response over the ensuing 3 years of study and therefore might have benefited from a change in treatment.ResultsWe found 39% of patients receiving therapy experienced either a medium or high level of concern of breakthrough after a year of treatment, and 89% of these patients went on to develop further breakthrough over years 2–4. Although 67% of the 61% of patients having no or low-level concern after a year of treatment also experienced further disease breakthrough, it was significantly less than the medium or high group.ConclusionThis study shows that the Canadian TOR may be an important tool for early treatment optimization.
Amphiboles from the Kola Superdeep Borehole: Fe3+ contents from
crystal-chemical analysis and Mössbauer spectroscopy
Authors: Uvarova Y. , Sokolova E. , Hawthorne F. C. , McCammon C. A. , Kazansky V. I. , Lobanov K. V. 
Published: July 2008

Abstract
The crystal structures of a suite of amphiboles from the Kola Superdeep
Borehole, Russia, have been refined to R values of ∼3% using single-crystal Mo-Kα
X-ray diffraction data. The same crystals used in the collection of the intensity
data were subsequently analysed by electron microprobe (EMP) and milliprobe
Mössbauer spectroscopy. Site populations were assigned from the results of
site-scattering refinement and stereochemical analysis, taking into account the
unit formula determined for each crystal. The
Fe3+/(Fe2++Fe3+)
values were derived (1) by least-squares refinement of the Mössbauer spectra, and
(2) SREF (Structure REFinement) by careful analysis of the mean bond lengths at
the M(2) site using two possible models for the
behaviour of Ti4+: (i) Ti4+ at
M(2); and (ii) Ti4+ at
M(1). The agreement between the SREF and
Mössbauer/EMP values for Fe3+ is very close for Ti4+ assigned
to M(2). This result indicates that the calculation of
Fe3+ contents in amphiboles from refined site populations
and <M(2)–O> distances are accurate. This paper
presents the first confirmation of this result.
An early metamorphic stage for the Variscan Ulten Zone gneiss (NE Italy): evidence from mineral inclusions in kyanite
Authors: Braga R. , Massonne H.-J. , Morten L. 
Published: July 2008

AbstractThe earlyP-Tevolution of a garnet-kyanite gneiss from the Variscan Ulten Zone has been defined by detailed petrographic observations leading to the detection of chlorite-epidote- and staurolite-bearing assemblages enclosed in kyanite porphyroblasts. Calculations ofP-Tpseudosections in the system NaCaKFeMgAlSiHO allowed us to constrain the evolution of these relics to the earliest metamorphic stages. The overall path shows aP-Tincrease to a peak of 11–12 kbar and 600–650°C followed by decompressional heating to 720°C and 9–10 kbar and final cooling at 7 kbar, 550–600°C. This clockwiseP-Tpath reflects crustal thickening and subsequent thermal decay related to the continental collision of the Variscan orogeny 330–340 Ma ago. Our study demonstrates that large kyanite porphyroblasts may preserve assemblages related to prograde metamorphic stages. As a result, the detection of mineral inclusions in kyanite can complement many similar studies on mineral suites hosted in garnet and zircon.
PRFdb: A database of computationally predicted eukaryotic programmed -1 ribosomal frameshift signals
Authors: Belew Ashton T , Hepler Nicholas L , Jacobs Jonathan L , Dinman Jonathan D 
Published: July 2008

Abstract

Background
The Programmed Ribosomal Frameshift Database (PRFdb) provides an interface to help researchers identify potential programmed -1 ribosomal frameshift (-1 PRF) signals in eukaryotic genes or sequences of interest.

Results
To identify putative -1 PRF signals, sequences are first imported from whole genomes or datasets, e.g. the yeast genome project and mammalian gene collection. They are then filtered through multiple algorithms to identify potential -1 PRF signals as defined by a heptameric slippery site followed by an mRNA pseudoknot. The significance of each candidate -1 PRF signal is evaluated by comparing the predicted thermodynamic stability (ΔG°) of the native mRNA sequence against a distribution of ΔG° values of a pool of randomized sequences derived from the original. The data have been compiled in a user-friendly, easily searchable relational database.

Conclusion
The PRFdB enables members of the research community to determine whether genes that they are investigating contain potential -1 PRF signals, and can be used as a metasource of information for cross referencing with other databases. It is available on the web at http://dinmanlab.umd.edu/prfdb.
Desflurane consumption during automated closed-circuit delivery is higher than when a conventional anesthesia machine is used with a simple vaporizer-O2-N2O fresh gas flow sequence
Authors: De Cooman Sofie , De Mey Nathalie , Dewulf Bram BC , Carette Rik , Deloof Thierry , Sosnowski Maurice , De Wolf Andre M , Hendrickx Jan FA 
Published: July 2008

Abstract

Background
The Zeus® (Dräger, Lübeck, Germany), an automated closed-circuit anesthesia machine, uses high fresh gas flows (FGF) to wash-in the circuit and the lungs, and intermittently flushes the system to remove unwanted N2. We hypothesized this could increase desflurane consumption to such an extent that agent consumption might become higher than with a conventional anesthesia machine (Anesthesia Delivery Unit [ADU®], GE, Helsinki, Finland) used with a previously derived desflurane-O2-N2O administration schedule that allows early FGF reduction.

Methods
Thirty-four ASA PS I or II patients undergoing plastic, urologic, or gynecologic surgery received desflurane in O2/N2O. In the ADU group (n = 24), an initial 3 min high FGF of O2 and N2O (2 and 4 L.min-1, respectively) was used, followed by 0.3 L.min-1 O2 + 0.4 L.min-1 N2O. The desflurane vaporizer setting (FD) was 6.5% for the first 15 min, and 5.5% during the next 25 min. In the Zeus group (n = 10), the Zeus® was used in automated closed circuit anesthesia mode with a selected end-expired (FA) desflurane target of 4.6%, and O2/N2O as the carrier gases with a target inspired O2% of 30%. Desflurane FA and consumption during the first 40 min were compared using repeated measures one-way ANOVA.

Results
Age and weight did not differ between the groups (P > 0.05), but patients in the Zeus group were taller (P = 0.04). In the Zeus group, the desflurane FA was lower during the first 3 min (P < 0.05), identical at 4 min (P > 0.05), and slightly higher after 4 min (P < 0.05). Desflurane consumption was higher in the Zeus group at all times, a difference that persisted after correcting for the small difference in FA between the two groups.

Conclusion
Agent consumption with an automated closed-circuit anesthesia machine is higher than with a conventional anesthesia machine when the latter is used with a specific vaporizer-FGF sequence. Agent consumption during automated delivery might be further reduced by optimizing the algorithm(s) that manages the initial FGF or by tolerating some N2 in the circuit to minimize the need for intermittent flushing.