bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evaluation of key microphysical parameters in three‐dimensional cloud‐model simulations using aircraft and multiparameter radar data
Authors: Brown Philip R. A. , Swann Hugh A. 
Published: October 2008

AbstractA 3‐d numerical model is being used for the development of improved parametrizations of convective transport processes in climate and numerical weather‐prediction models. In common with similar cloud‐resolving models, it uses a 3‐phase bulk‐water parametrization of the microphysical processes. the comparison of results from such models with observed case‐studies represents an important step in their development and a key activity of the Global Energy and Water Cycle Experiment Cloud System Study.This paper presents observations and model results from the case of a weakly convective precipitating cloud that occurred on 22 June 1990 over central southern England. the cloud was observed by both an instrumented research aircraft and a dual‐polarization radar. the combination of these measurements provides information on the dominant precipitation particle types, their density, number concentration, and characteristic size, and enables the identification of key microphysical processes. the observations were used to provide guidance on the numerical values of some of the variable parameters in the microphysics scheme. Observed values of No,G, the intercept parameter for graupel, lay in the range 104 to 107 m−4. the comparison of observed radar reflectivities with those calculated from in situ particle size spectra suggests that the density of rimed precipitation particles decreased from around 0.5 g cm−3 in the most intense precipitation to around 0.1 g cm−3 towards the cloud edges.A number of model sensitivity studies were performed to examine the impact of changes in these parameters on the model cloud and precipitation fields. For this case‐study, it was found that the total surface precipitation was generally insensitive to such changes, varying by less than 10%. Reductions of 35% occurred for model runs in which the graupel fall speed was reduced and for a model run with only ‘warm‐rain’ microphysics. Much larger variations in the range 50‐100% occurred in the total cloud ice and snow contents.The modelling study identifies a number of differences between runs which could not be resolved owing to the lack of in situ data in certain regions of the cloud. Some of the requirements for improved observational methods and procedures are discussed.
Convective destabilization by a tropopause fold diagnosed using potential‐vorticity inversion
Authors: Griffiths Morwenna , Thorpe Alan J. , Browning Keith A. 
Published: October 2008

AbstractThere is observational evidence to suggest that at the time tropopause folds in extra‐tropical cyclones are descending into the mid troposphere there is frequently a destablization of the lower troposphere to moist convection. Here we consider the dynamical reasons for such a linkage using so‐called potential vorticity (PV) attribution concepts. In particular PV inversion is used to find the wind shear attributable to the tropopause fold itself. Then this shear is used to quantify the tendency to generate regions of potential instability. For an observed case of a modest tropopause fold it is found that the PV anomaly contained in the tropopause fold contributed substantially to the instantaneous convective destabilization in the sense of increasing the potential instability. Indeed, at some locations, it overcame a tendency to stabilize by the atmosphere without the fold. On the other hand, only a fraction of the region with increased potential instability experienced sufficient large‐scale ascent to lead to convection and it remains to be seen whether folds in general make a significant contribution to the generation of potential instability that can actually be realized. The importance of tropopause folds, or indeed of tropopause depressions in general in the context of convection, is that their small horizontal scale has the potential to focus and amplify any convective destabilization locally. This may account for the localization of outbreaks of severe convective weather which it is important to forecast accurately. Currently numerical weather‐prediction models often do not handle these small scales very accurately.
Influence of the Indian summer monsoon on ENSO
Authors: Kirtman Ben P. , Shukla J. 
Published: October 2008

AbstractHistorical records (approximately 100 years) of Indian summer monsoon rainfall and El Niño/Southern Oscillation (ENSO) indices show a strong negative correlation. This negative correlation is strongest for east Pacific sea surface temperature anomalies (SSTA) that occur during the months of December through to March, which is about three to six months immediately following the monsoon season (June to September). Based on this correlation, one is tempted to speculate that monsoon variability affects ENSO variability. However, it is well known that ENSO is phase locked to the annual cycle in that the largest SSTA occur at the end of the calendar year. In other words, an ENSO which originated well before the summer monsoon season will have its peak amplitude at the end of the calendar year. The purpose of this study is to explain the impact of the monsoon which has a strong seasonal preference on ENSO which has a life cycle of about 4 years.First, a 50‐year atmospheric general‐circulation model simulation with climatological SST is examined to determine the tropical Pacific wind‐stress anomalies that are associated with a variable monsoon but that are also independent of SST variability in the tropical Pacific. Using simple statistical techniques, it is found that a weak (strong) monsoon results in a weakening (strengthening) of the trade winds over the tropical Pacific. To examine how these 'monsoon‐forced wind‐stress anomalies' in the tropical Pacific affect ENSO, simulations were made with a simple coupled model that does not include the effects of a variable monsoon. The effects of the monsoon are then added in the coupled model by either specifying the strength of the monsoon or by parametrizing the strength of the monsoon in terms of the coupled‐model simulated SSTA in the east Pacific. Based on these coupled simulations, a variable monsoon enhances the ENSO variability, particularly three to six months after the monsoon ends, and can also serve as a trigger mechanism for ENSO. It is found that an ongoing warm (cold) ENSO event is made even warmer (colder) by a weak (strong) monsoon. Similarly, warm (cold) events are weakened by a strong (weak) monsoon. These results also reproduce the observed lag/lead ENSO‐monsoon relation where the maximum negative correlation between the monsoon and the SSTA in the east Pacific occurs 3‐6 months after the monsoon season.
On the vertical velocity in an isentropic layer
Authors: Verkley W. T. M. 
Published: October 2008

AbstractWe investigate the dynamics of an isentropic layer of air, governed by the hydrostatic primitive equations. In such a layer the horizontal velocity is independent of height if this is assumed to be the case at some initial time. From the mass‐conservation equation in pressure coordinates it follows that ω, the material derivative of the pressure, varies linearly with pressure. From the mass‐conservation equation in height coordinates the vertical velocity ω is obtained. The resulting expression is shown to be in accordance with Richardson's equation for the vertical velocity in a general hydrostatic atmosphere, when particularized to an isentropic layer.
Consensus building in the planning process: Benefits from a “hard” modeling approach
Authors: Winch Graham W. 
Published: October 2008

AbstractThis article examines the role that building and using a system dynamics model plays in developing consensus within management teams facing key strategic decisions: A shared view emerges within the team as individual views of the company, its industry, and the socioeconomic climate are articulated and compared. Examples are given based on two actual consulting assignments in which differing views concerning the competitive environment and the general business outlook initially pointed to quite different strategies. The emergence of consensus was considered a major benefit in addition to the forecasts and quantitative evaluations the model provided. In its analysis and examples, this article emphasizes both the “hard” benefits of forecasts and an objective framework for quantitative evaluations and the “soft” benefits of building consensus within management teams.
A compiler for parsing schemata
Authors: Gómez‐Rodríguez C. , Vilares J. , Alonso M. A. 
Published: October 2008

AbstractWe present a compiler that can be used to automatically obtain efficient Java implementations of parsing algorithms from formal specifications expressed as parsing schemata. The system performs an analysis of the inference rules in the input schemata in order to determine the best data structures and indexes to use, and to ensure that the generated implementations are efficient. The system described is general enough to be able to handle all kinds of schemata for different grammar formalisms, such as context‐free grammars and tree‐adjoining grammars, and it provides an extensibility mechanism allowing the user to define custom notational elements. This compiler has proven very useful for analyzing, prototyping and comparing natural‐language parsers in real domains, as can be seen in the empirical examples provided at the end of the paper. Copyright © 2008 John Wiley & Sons, Ltd.
An action potential‐induced and ryanodine sensitive calcium transient dynamically regulates transmitter release at synapses between Lymnaea neurons
Authors: Dunn T.W. , Montgomery E.A. , Syed N.I. 
Published: October 2008

AbstractThe notion that calcium released through ryanodine receptors effects presynaptic neurotransmitter release is gaining acceptance with the observation that this calcium does indeed contribute to both action potential‐evoked and spontaneous transmitter release in a variety of preparations. However, the dynamics of this calcium release and its impact on transmitter release has not yet been fully elucidated. Moreover, in contrast to vertebrate synapses, much less is known about the involvement of ryanodine receptors in the regulation of transmitter release at invertebrate synapses. In this study, we reconstructed specific synapses between individually identifiable preand postsynaptic neurons from Lymnaea to demonstrate that although ryanodine reduces the amplitude of the action potential‐induced calcium transient, it does not however, alter the resting calcium level. These data suggest that action potential‐induced calcium release through ryanodine receptors is fast and highly dynamic and in turn regulates transmitter release at reconstructed synapses between Lymnaea neurons. This study thus provides direct evidence that a dynamic ryanodine receptor‐mediated calcium transient occurs with the presynaptic action potential. Synapse 63:61–68, 2009. © 2008 Wiley‐Liss, Inc.
Altered netrin‐1 receptor expression in dopamine terminal regions following neonatal ventral hippocampal lesions in the rat
Authors: Flores Cecilia , Bhardwaj Sanjeev K. , Labelle‐Dumais Cassandre , Srivastava Lalit K. 
Published: October 2008

AbstractNeonatal ventral hippocampal (nVH) lesions in rats, which model certain features of schizophrenia, alter dopamine (DA)‐mediated behaviors in adulthood. The precise mechanisms underlying these effects remain elusive; however, neuronal reorganization within the medial prefrontal cortex (mPFC) has been suggested. Netrins are developmental cues that organize brain wiring, including the mesocorticolimbic DA circuitry. We showed recently that the netrin‐1 receptors DCC and UNC5H are highly expressed by DA neurons and that variation in DCC levels during development lead to profound changes in mesocorticolimbic DA function and behavior in adulthood. We hypothesized that changes in netrin‐1 receptor function could be one of the mechanisms producing enduring changes in DA function in nVH‐lesioned animals. To begin to explore this idea, we examined the effects of nVH lesions on DCC and UNC5H expression in brain regions receiving robust DA innervation; the mPFC, striatum, and nucleus accumbens (NAcc) at three developmental time points; 3 days after lesion, before puberty and during early adulthood. Expression was also examined in the cerebellar simple lobule; a brain region deprived of DA innervation. Neonatal VH lesions produced dynamic changes in DCC expression in the mPFC and NAcc. The direction and magnitude of these changes depended on the developmental age and brain region examined and were specific to regions receiving DA innervation. Although further studies are required to understand the functional significance of these changes, these results raise the interesting possibility that nVH lesions, and perinatal insults in general, may exert their neuronal reorganizational effects by modulating netrin‐1 function. Synapse 63:54–60, 2009. © 2008 Wiley‐Liss, Inc.
Predictors of outcome in a cohort of women with chronic pelvic pain – A follow‐up study
Authors: Weijenborg Philomeen Th. M. , Le Kuile Moniek M. , Gopie Jessica P. , Spinhoven Philip 
Published: October 2008

ABSTRACTBackground: Chronic pelvic pain (CPP) in women is a long‐lasting condition.Aims: To explore changes in pain intensity, adjustment to pain, pain appraisal and coping strategies as well as to evaluate whether baseline pain appraisals and coping strategies and their changes were associated with outcome in the long term.Methods: A follow‐up study was conducted on all consecutive women who had visited a CPP‐team of a university hospital. After an average period of 3.2 years 64% of them (N=84) completed questionnaires at baseline and follow‐up.Results: A reduction in pain intensity (p<.001, d=.6), improvement in adjustment to pain (SF‐36 Physical Component Summary (p<.001, d=.4) and depressive symptoms (p<.01, d=.2)), as well as a reduction in catastrophizing pain (p<.01, d=.4) and an increase in perceived pain control (p<.01, d=.3) were observed. Neither biographic nor clinical variables were related with these changes. Pain appraisal and coping strategies at baseline did not predict changes from baseline in pain intensity. However, baseline levels of perceived pain control correlated with a change in depressive symptoms (r=−.27, p<.05), also after adjustment for pain intensity at baseline (r=−.28, p<.05). Changes from baseline in levels of catastrophizing pain were associated with changes in pain intensity (r=.44, p<.01), SF‐36 Physical Component Summary (r=−.34, p<.01) and depressive symptoms (r=.71, p<.01).Conclusion: At a 3 year follow‐up, improvement in pain intensity in women with CPP was not associated with baseline pain appraisals and coping strategies. A reduction in catastrophizing was related to better outcome in the long term.
Oral micronized progesterone for prevention of preterm birth
Authors: Rai Pushpanjali , Rajaram Shalini , Goel Neerja , Ayalur Gopalakrishnan Radhika , Agarwal Rachna , Mehta Sumita 
Published: October 2008

AbstractObjectiveTo evaluate oral micronized progesterone (OMP) to prevent preterm birth (PTB).MethodsA randomized, double‐blind, placebo‐controlled trial of 150 women with at least one PTB who received 100 mg of OMP or placebo twice a day from recruitment (18–24 weeks) until 36 weeks or delivery.ResultsPTB occurred in 29 (39.2%) women in the OMP group (n = 74) compared with 44 (59.5%) in the control group (n = 74, P = 0.002). Mean gestational age at delivery was higher in the OMP group (36.1 vs 34.0 weeks, P < 0.001). Fewer preterm births occurred between 28 and 31 weeks plus 6 days in the OMP group (RR 0.20; 95% CI, 0.05–0.73, P < 0.001). Neonatal age at delivery (34 vs 32 weeks, P < 0.001), birth weight (2400 vs 1890 g, P < 0.001), NICU stay (> 24 h, P < 0.001), and Apgar scores (P < 0.001) were more favorable in the OMP group, and fewer neonatal deaths occurred (3 vs 7, P = 0.190).ConclusionOMP reduced the risk of PTB between 28 and 31 weeks plus 6 days, NICU admissions, and neonatal morbidity and mortality in high risk patients.
An unusual case of warfarin-induced pinna skin necrosis
Authors: Del Pero M Martinez , Verma S , Espeso A , Griffiths M , Jani P 
Published: October 2008

AbstractIntroduction:Warfarin-induced skin necrosis is a rare but recognised complication of this drug. The condition predominantly affects the breasts, buttocks and thighs of obese, peri-menopausal women. We present the case of a patient with the condition in an unusual site, and we discuss the management challenges involved.Case report:An 82-year-old man presented to the ENT department with a diagnosis of pinna haematoma. There was no history of trauma or infection. The patient was taking warfarin long-term for recurrent deep vein thrombosis. Two weeks prior to admission, the patient had had a loading course of warfarin following surgery. Multiple clinical teams were involved in treatment. The only abnormal laboratory investigation was a low protein S level; biopsy showed skin necrosis.Conclusion:In this case, the unusual presentation created diagnostic confusion, and may have precipitated aggressive surgical debridement. However, a more conservative management strategy was used, which we would recommend in future.
Spontaneous intracranial hypotension presenting to the ENT surgeon: case report
Authors: Street S , Fagan P , Roche J 
Published: October 2008

AbstractObjective:To highlight a case of spontaneous intracranial hypotension presenting to the ENT surgeon.Method:We present a case report and a review of the literature concerning spontaneous intracranial hypotension.Results:Spontaneous intracranial hypotension is a rare diagnosis, particularly to the ENT surgeon. We report a patient with tinnitus, hearing loss and headache, symptoms suggestive of an ENT diagnosis such as Ménière's disease or vestibular schwannoma. However, magnetic resonance imaging revealed the characteristic findings of spontaneous intracranial hypotension. The patient's symptoms resolved, except for a mild residual tinnitus, with conservative management alone.Conclusion:This case highlights the importance of considering spontaneous intracranial hypotension as a differential diagnosis of certain ENT symptoms.
Simulation of optical breakdown in nitrogen by focused short laser pulses of 1064 nm wavelength
Authors: Tartar G. , Ranner H. , Winter F. , Wintner E. 
Published: October 2008

AbstractA kinetic model of electron cascade growth in the electromagnetic field of a focused intense laser pulse as used for laser spark generation in gases has been numerically implemented in Visual C code. The effects considered comprise Drude absorption, diffusive kinetic and inelastic losses as well as (three-particle) electron recombination. The objectives were to illustrate the dynamic process of gas ionization, and to clarify the pressure dependence of known breakdown thresholds within a range of about 2 × 104 to 2 × 106 Pa of initial pressure. Two-dimensional (cylindric coordinates) simulations of the optical breakdown in nitrogen were conducted on a commercial PC, using constant values for the collision cross section (2 × 10−19 m2), prevalent electronic excitation states (~4.8 eV), and a laser wavelength of 1064 nm. A certain aerosol concentration on the order of 3 ppb was assumed in order to provide initial electrons for cascade growth. Exemplary results with laser pulse energy of 26 mJ, pulse duration of 14 ns and an 18 µm focal spot size illustrate the dynamic process of ionization within a very short time period of less than 0.5 ns. The kinetic energy of the electrons is found to increase sharply up to more than 100,000 K on breakdown. A series of simulations considered the minimum pulse energy of breakdown (MPE) under variation of initial pressure. Identical laser parameters as in experiments conducted previously were used and the results are in excellent agreement with respect to curve shapes, i.e., MPE ~1/p0.4 in the first experiment and MPE ~1/p0.3 in the second one. The absolute values lie within a factor of two, which is explained by model abstraction and input data uncertainties.
Political correctness and the American newspaper: the case of the Los Angeles Times Stylebook
Authors: Miles Jack 
Published: October 2008

ON DECEMBER 2, 1993, David Nyhan of the Boston Globe published an article entitled “The Thought Police Strike Again.” In a parody of novelist Raymond Chandler's immortal Los Angeles detective, Philip Marlowe, Nyhan wrote:“I was in my office, on the fringe of the ghetto, feeling gypped because a check had bounced, watching the crazy divorcée in the next office, a real babe who used to be a nifty co-ed before she married her hillbilly. He was a piece of white trash whose holy roller ancestors fought the Indians.
Effectiveness of influenza vaccination in the elderly in South Africa
Authors: van VUUREN A. , RHEEDER P. , HAK E. 
Published: October 2008

SUMMARYThis study primarily aimed to estimate the association between influenza vaccination and the occurrence of hospitalization for acute respiratory or cardiovascular diseases, or all-cause death during the influenza season in an elderly population in South Africa. We conducted a nested case-control study using data from a cohort of 45 522 elderly members of a private medical funding organization during the moderate 2004 influenza season. In 1282 (2·8%) subjects the combined outcome occurred and the influenza vaccination rate in controls was 15·4%. After adjustments for measured confounders, vaccination was associated with a statistically significant reduction of 19% (95% confidence interval 3·1–32·9) in the combined outcome. Post-hoc sensitivity analysis of the potential impact of potential healthy user bias showed that confounding, if present, could have caused this finding. Our data were inconclusive regarding the benefits of influenza vaccination in elderly persons in South Africa and given the low vaccine uptake, long-term follow-up is warranted.
Socioeconomic risk factors for bacteraemic pneumococcal pneumonia in adults
Authors: FLORY J. H. , JOFFE M. , FISHMAN N. O. , EDELSTEIN P. H. , METLAY J. P. 
Published: October 2008

SUMMARYDemographic and clinical risk factors are important in guiding vaccination policy for pneumococcal pneumonia. We present data on these variables from a population-based surveillance network covering adult bacteraemic pneumococcal pneumonia (BPP) in the Delaware Valley region from 2002 to 2004. Surveillance data were used with U.S. Census data and a community health survey to calculate stratified incidence rates. Missing data were handled using multiple imputation. Overall rates of adult BPP were 10·6 cases/100 000 person-years. Elevated rates were seen in the elderly (>65 years), Native Americans, African Americans, the less-educated (less than high-school education), the poor, smokers, and individuals with histories of asthma, cancer, or diabetes. Multivariable modelling suggested that income was more robustly associated with risk than African American race. Of methodological interest, this association was not apparent if census block-group median income was used as a proxy for self-reported income. Further research on socioeconomic risk factors for BPP is needed.