bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cloud and Radiative Characteristics of Tropical Deep Convective Systems in Extended Cloud Objects from CERES Observations
Authors: Eitzen Zachary A. , Xu Kuan-Man , Wong Takmeng 
Published: July 2009

Abstract
The physical and radiative properties of tropical deep convective systems for the period from January to August 1998 are examined with the use of Clouds and the Earth’s Radiant Energy System Single-Scanner Footprint (SSF) data from the Tropical Rainfall Measuring Mission satellite. Deep convective (DC) cloud objects are contiguous regions of satellite footprints that fulfill the DC criteria (i.e., overcast footprints with cloud optical depths &gt;10 and cloud-top heights &gt;10 km). Extended cloud objects (ECOs) start with the original cloud object but include all other cloudy footprints within a rectangular box that completely covers the original cloud object. Most of the non-DC footprints are overcast but have optical depths and/or cloud-top heights that are too low to fit the DC criteria. The histograms of cloud physical and radiative properties are analyzed according to the size of the ECO and the SST of the underlying ocean.
Larger ECOs are associated with greater magnitudes of large-scale upward motion, which supports stronger convection for larger sizes of ECOs. This leads to shifts toward higher values in the DC distributions of cloud-top height, albedo, condensate water path, and cloud optical depth. However, non-DC footprints become less reflective with increasing ECO size, as the longer-lived large convective systems have more time to develop thin cirrus anvils. The proportion of DC footprints remains fairly constant with size. The proportion of DC footprints also remains nearly constant with SST within a given size class, although the number of footprints per object increases with SST for large objects. As SSTs increase, there is a decrease in the proportion of updraft water that goes into detrainment, causing the non-DC distributions of albedo, condensate water path, and cloud optical depth to shift toward lower values. The all-cloud distributions of cloud-top temperature and outgoing longwave radiation (OLR) shift toward lower values as SST increases owing to the increase in convective instability with SST. Both the DC and non-DC distributions of cloud-top temperature do not change much with satellite precession cycle, supporting the fixed anvil temperature hypothesis of Hartmann and Larson. When a joint histogram is formed from the cloud-top pressures and cloud optical depths of the ECOs, it is very similar to the corresponding histogram of the deep convective weather state obtained by cluster analysis of International Satellite Cloud Climatology Project data.
Vertical Heating Structures Associated with the MJO as Characterized by TRMM Estimates, ECMWF Reanalyses, and Forecasts: A Case Study during 1998/99 Winter
Authors: Jiang Xianan , Waliser Duane E. , Olson William S. , Tao Wei-Kuo , L’Ecuyer Tristan S. , Li Jui-Lin , Tian Baijun , Yung Yuk L. , Tompkins Adrian M. , Lang Stephen E. , Grecu Mircea 
Published: July 2009

Abstract
The Madden–Julian oscillation (MJO) is a fundamental mode of the tropical atmosphere variability that exerts significant influence on global climate and weather systems. Current global circulation models, unfortunately, are incapable of robustly representing this form of variability. Meanwhile, a well-accepted and comprehensive theory for the MJO is still elusive. To help address this challenge, recent emphasis has been placed on characterizing the vertical structures of the MJO. In this study, the authors analyze vertical heating structures by utilizing recently updated heating estimates based on the Tropical Rainfall Measuring Mission (TRMM) from two different latent heating estimates and one radiative heating estimate. Heating structures from two different versions of the European Centre for Medium-Range Weather Forecasts (ECMWF) reanalyses/forecasts are also examined. Because of the limited period of available datasets at the time of this study, the authors focus on the winter season from October 1998 to March 1999.
The results suggest that diabatic heating associated with the MJO convection in the ECMWF outputs exhibits much stronger amplitude and deeper structures than that in the TRMM estimates over the equatorial eastern Indian Ocean and western Pacific. Further analysis illustrates that this difference might be due to stronger convective and weaker stratiform components in the ECMWF estimates relative to the TRMM estimates, with the latter suggesting a comparable contribution by the stratiform and convective counterparts in contributing to the total rain rate. Based on the TRMM estimates, it is also illustrated that the stratiform fraction of total rain rate varies with the evolution of the MJO. Stratiform rain ratio over the Indian Ocean is found to be 5% above (below) average for the disturbed (suppressed) phase of the MJO. The results are discussed with respect to whether these heating estimates provide enough convergent information to have implications on theories of the MJO and whether they can help validate global weather and climate models.
Basinwide Integrated Volume Transports in an Eddy-Filled Ocean
Authors: Kanzow T. , Johnson H. L. , Marshall D. P. , Cunningham S. A. , Hirschi J. J.-M. , Mujahid A. , Bryden H. L. , Johns W. E. 
Published: July 2009

Abstract
The temporal evolution of the strength of the Atlantic Meridional Overturning Circulation (AMOC) in the subtropical North Atlantic is affected by both remotely forced, basin-scale meridionally coherent, climate-relevant transport anomalies, such as changes in high-latitude deep water formation rates, and locally forced transport anomalies, such as eddies or Rossby waves, possibly associated with small meridional coherence scales, which can be considered as noise. The focus of this paper is on the extent to which local eddies and Rossby waves when impinging on the western boundary of the Atlantic affect the temporal variability of the AMOC at 26.5°N. Continuous estimates of the AMOC at this latitude have been made since April 2004 by combining the Florida Current, Ekman, and midocean transports with the latter obtained from continuous density measurements between the coasts of the Bahamas and Morocco, representing, respectively, the western and eastern boundaries of the Atlantic at this latitude.
Within 100 km of the western boundary there is a threefold decrease in sea surface height variability toward the boundary, observed in both dynamic heights from in situ density measurements and altimetric heights. As a consequence, the basinwide zonally integrated upper midocean transport shallower than 1000 m—as observed continuously between April 2004 and October 2006—varies by only 3.0 Sv (1 Sv ≡ 106 m3 s−1) RMS. Instead, upper midocean transports integrated from western boundary stations 16, 40, and 500 km offshore to the eastern boundary vary by 3.6, 6.0, and 10.7 Sv RMS, respectively.
The reduction in eddy energy toward the western boundary is reproduced in a nonlinear reduced-gravity model suggesting that boundary-trapped waves may account for the observed decline in variability in the coastal zone because they provide a mechanism for the fast equatorward export of transport anomalies associated with eddies impinging on the western boundary. An analytical model of linear Rossby waves suggests a simple scaling for the reduction in thermocline thickness variability toward the boundary. Physically, the reduction in amplitude is understood as along-boundary pressure gradients accelerating the fluid and rapidly propagating pressure anomalies along the boundary. The results suggest that the local eddy field does not dominate upper midocean transport or AMOC variability at 26.5°N on interannual to decadal time scales.
Simultaneous Estimation of Microphysical Parameters and the Atmospheric State Using Simulated Polarimetric Radar Data and an Ensemble Kalman Filter in the Presence of an Observation Operator Error
Authors: Jung Youngsun , Xue Ming , Zhang Guifu 
Published: July 2009

Abstract
The impacts of polarimetric radar data on the estimation of uncertain microphysical parameters are investigated through observing system simulation experiments when the effects of uncertain parameters on the observation operators are also considered. Five fundamental microphysical parameters (i.e., the intercept parameters of rain, snow, and hail and the bulk densities of snow and hail) are estimated individually or collectively using the ensemble square root Kalman filter. The differential reflectivity ZDR, specific differential phase KDP, and radar reflectivity at horizontal polarization ZH are used individually or in combinations for the parameter estimation while the radial velocity and ZH are used for the state estimation. In the process, the parameter values estimated in the previous analysis cycles are used in the forecast model and in observation operators in the ensuing assimilation cycle. Analyses are first performed that examine the sensitivity of various observations to the microphysical parameters with and without observation operator error. The results are used to help interpret the filter behaviors in parameter estimation. The experiments in which either a single or all five parameters contain initial errors reveal difficulties in estimating certain parameters using ZH alone when observation operator error is involved. Additional polarimetric measurements are found to be beneficial for both parameter and state estimation in general. It is found that the polarimetric data are more helpful when the parameter estimation is not very successful with ZH alone. Between ZDR and KDP, KDP is found to produce larger positive impacts on parameter estimation in general while ZDR is more useful in the estimation of the intercept parameter of hail. In the experiments that attempt to correct errors in all five parameters, the filter fails to correctly estimate the snow intercept parameter and the density with or without polarimetric data, seemingly due to the small sensitivity of the observations to these parameters and complications involving the observation operator error. When these two snow parameters are not corrected during the estimation process, the estimations of the other three parameters and of all of the state variables are significantly improved and the positive impacts of polarimetric data are larger than that of a five-parameter estimation. These results reveal the significant complexity of the estimation problem for a highly nonlinear system and the need for careful sensitivity analysis. The problem is potentially more challenging with real-data cases when unknown sources of model errors are inevitable.
A Diagnostic Study of the Intensity of Three Tropical Cyclones in the Australian Region. Part II: An Analytic Method for Determining the Time Variation of the Intensity of a Tropical Cyclone*
Authors: Lajoie France , Walsh Kevin 
Published: July 2009

AbstractThe observed features discussed in Part I of this paper, regarding the intensification and dissipation of Tropical Cyclone Kathy, have been integrated in a simple mathematical model that can produce a reliable 15–30-h forecast of (i) the central surface pressure of a tropical cyclone, (ii) the sustained maximum surface wind and gust around the cyclone, (iii) the radial distribution of the sustained mean surface wind along different directions, and (iv) the time variation of the three intensity parameters previously mentioned. For three tropical cyclones in the Australian region that have some reliable ground truth data, the computed central surface pressure, the predicted maximum mean surface wind, and maximum gust were, respectively, within ±3 hPa and ±2 m s−1 of the observations. Since the model is only based on the circulation in the boundary layer and on the variation of the cloud structure in and around the cyclone, its accuracy strongly suggests that (i) the maximum wind is partly dependent on the large-scale environmental circulation within the boundary layer and partly on the size of the radius of maximum wind and (ii) that all factors that contribute one way or another to the intensity of a tropical cyclone act together to control the size of the eye radius and the central surface pressure.
Study of the Periodicities of Lightning Activity in Three Main Thunderstorm Centers Based on Schumann Resonance Measurements
Authors: Nieckarz Zenon , Zięba Stanisław , Kułak Andrzej , Michalec Adam 
Published: July 2009

Abstract
Time variations of lightning activity in the three main tropical thunderstorm centers located in the Maritime Continent (Pakistan, India, Southeast Asia, Indonesia, and Australia), Africa, and the Americas are analyzed using a lightning activity index IRS, which is calculated from the resonances of magnetic field in the extremely low frequency range—the Schumann resonances—which were observed at Hylaty station (Poland) in the time interval July 2005–May 2006. Power spectrum analysis of the IRS series is carried out for this time interval. The annual and semiannual variations are shown in all of the series together with the following characteristic periodicities: 45 (Madden–Julian oscillation), 17.6, 13.5, and 4.8 days, seen mainly in the series describing the lightning activity of the Maritime Continent. In addition, maps of the dynamical power spectrum are constructed. They present variability both in the values of characteristic periods 26–30, 17–22, 12–14, 9–10, and 5–7 days and in their duration. During the studied time interval, according to these indices, the African center was the most active, whereas the American and Maritime Continent centers showed a similar level of activity. The largest differences among the centers were observed in the summer months in the Northern Hemisphere.
Facilitating the participation of people with aphasia in research: a description of strategies
Authors: Dalemans Ruth , Wade Derick T , van den Heuvel Wim JA , de Witte Luc P 
Published: July 2009

Background: People with aphasia are often excluded from research because of their communication impairments, especially when an investigation into the communication impairment is not the primary goal. In our research concerning social participation of people with aphasia, we wanted to include people with mild, moderate as well as severe aphasia. Aim: To suggest strategies and techniques for research in people with aphasia based upon experiences in conducting research in this group of people. Methods: We conducted a qualitative study and a quantitative study in people with aphasia concerning their social participation. In these studies different strategies were developed based upon the literature, conversations with people with aphasia and speech and language therapists, to facilitate the inclusion of people with aphasia, even those with severe communication problems. Several strategies were evaluated. The strategies used and our experiences are outlined in this report. Main contribution: It is possible to conduct research in this group. Several strategies were helpful to make this mission possible: the use of pre-structured diaries, the use of in-depth interviews with attention to non-verbal communication, the use of existing measurements, adjusted for people with aphasia by: using pictograms, placing one question per page, bolding the key concepts in the question, using large font, visualizing the answering possibilities in words and in pictures, reducing the question length, and excluding negatives in the question. Conclusion: Research in people with aphasia is possible when using strategies adjusted to the communicative impairment.
Gadolinium-enhancing or active T2 magnetic resonance imaging lesions in multiple sclerosis clinical trials?
Authors: Bonzano L , Roccatagliata L , Mancardi GL , Sormani MP 
Published: July 2009

Background The treatment effects in multiple sclerosis (MS) clinical trials are often estimated by monitoring disease activity by the count of “active” plaques on T2-weighted or gadolinium (Gd)-enhanced T1-weighted magnetic resonance imaging (MRI). Objective To evaluate the relationship between the treatment effects estimated on T2-weighted or Gd-enhanced T1-weighted MRI. Methods Data were extracted from published randomized clinical trials in relapsing-remitting MS with frequent MRI, reporting both active T2 and Gd-enhancing lesions. A regression analysis was performed between the treatment effects estimated on the two different MRI endpoints. Results A strong association was found between the treatment effect on Gd-enhancing lesions and on active T2 lesions (R2 = 0.93), and the treatment effect estimates were almost the same (slope = 0.96). Conclusion Defining either active T2 or Gd-enhancing lesions as MRI endpoint seems to be not crucial for monitoring MRI activity in MS clinical trials. The choice of the best MRI endpoint should be based on different considerations (e.g., sensitivity, reproducibility, time for assessment, safety, and patients’ comfort). Further monitoring active T2 lesions could allow less expensive trials, without requiring injection of Gd-based contrast agents.
Lower urinary tract dysfunction in acute disseminated encephalomyelitis
Authors: Panicker JN , Nagaraja D , Kovoor JME , Nair KPS , Subbakrishna DK 
Published: July 2009

Background Lower urinary tract dysfunction (LUTD) in multiple sclerosis has been well documented. However, its occurrence and outcome in acute disseminated encephalomyelitis (ADEM) has only been variably reported. Objective To evaluate LUTD in ADEM, correlation with other neurological deficits, and outcome. Methods Patients with ADEM having significant LUTD were evaluated. LUTD was evaluated by symptom analysis, ultrasonography, and urodynamics. Storage symptoms were managed using antimuscarinics and significant voiding dysfunction by catheterization. Results Of 61 patients, 20 (33%) had LUTD. Voiding dysfunction was more common and 16 patients were in urinary retention. Cystometry demonstrated detrusor overactivity in four patients and underactivity in four patients. Incontinence was reported more often in patients with frontoparietal white matter changes in MR imaging. LUTD was found to be associated with occurrence of paraparesis or tetraparesis, though did not predict functional outcome at discharge. At 3 months follow up, five patients continued to have LUTD and urgency and hesitancy were commonest symptoms. Conclusion LUTD is common in ADEM, especially in patients with lower limb pyramidal involvement and its causes multifactorial. Presence of LUTD does not influence the functional outcome of patients with ADEM. Recovery may be incomplete and symptoms may persist even after recovery of other neurological deficits.
Dose-dependent melanonychia by mitoxantrone
Authors: Reinsberger C , Meuth SG , Wiendl H 
Published: July 2009

We report an unusual case of a 43-year old female patient suffering from multiple sclerosis, who was treated with mitoxantrone. Few weeks after treatment initiation a hyperpigmentation of the patient’s left thumb and index was noted. Following dose-reduction (from 12 to 10 mg/m2) and over the further course of mitoxantrone treatment the discoloration slightly faded. Although mitoxantrone is known to cause hyperpigmentation of various tissues this is the first report of melanonychia without hyperpigmentation of other tissue. Albeit speculative, pathogenesis of selective melanonychia by mitoxantrone could involve selective activation of nail matrix melanocytes or endocrine disturbances involving melanocyte stimulating hormone.
Distinctive interactions of the Arabidopsis homolog of the 30 kD subunit of the cleavage and polyadenylation specificity factor (AtCPSF30) with other polyadenylation factor subunits
Authors: Rao Suryadevara , Dinkins Randy D , Hunt Arthur G 
Published: July 2009

Abstract

Background
The Arabidopsis ortholog of the 30 kD subunit of the mammalian Cleavage and Polyadenylation Specificity Factor (AtCPSF30) is an RNA-binding endonuclease that is associated with other Arabidopsis CPSF subunits (orthologs of the 160, 100, and 73 kD subunits of CPSF). In order to further explore the functions of AtCPSF30, the subcellular distribution of the protein was examined by over-expressing fusion proteins containing fluorescent reporters linked to different CPSF subunits.

Results
It was found that AtCPSF30 by itself localizes, not to the nucleus, but to the cytoplasm. AtCPSF30 could be found in the nucleus when co-expressed with AtCPSF160 or AtCPSF73(I), one of the two Arabidopsis orthologs of CPSF73. This re-directing of AtCPSF30 indicates that AtCPSF30 is retained in the nucleus via interactions with either or both of these other CPSF subunits. Co-expression of AtCSPF30 with AtCPSF100 altered the location, not of AtCPSF30, but rather of AtCPSF100, with these proteins residing in the cytoplasm. Deletion of plant-specific N- or C-terminal domains of AtCPSF30 abolished various of the interactions between AtCPSF30 and other CPSF subunits, suggesting that the plant CPSF complex assembles via novel protein-protein interactions.

Conclusion
These results suggest that the nuclear CPSF complex in plants is a dynamic one, and that the interactions between AtCPSF30 and other CPSF subunits are different from those existing in other eukaryotes.
Developmental changes in the expression of creatine synthesizing enzymes and creatine transporter in a precocial rodent, the spiny mouse
Authors: Ireland Zoe , Russell Aaron P , Wallimann Theo , Walker David W , Snow Rod 
Published: July 2009

AbstractBackgroundCreatine synthesis takes place predominately in the kidney and liver via a two-step process involving AGAT (L-arginine:glycine amidinotransferase) and GAMT (guanidinoacetate methyltransferase). Creatine is taken into cells via the creatine transporter (CrT), where it plays an essential role in energy homeostasis, particularly for tissues with high and fluctuating energy demands. Very little is known of the fetal requirement for creatine and how this may change with advancing pregnancy and into the early neonatal period. Using the spiny mouse as a model of human perinatal development, the purpose of the present study was to comprehensively examine the development of the creatine synthesis and transport systems.ResultsThe estimated amount of total creatine in the placenta and brain significantly increased in the second half of pregnancy, coinciding with a significant increase in expression of CrT mRNA. In the fetal brain, mRNA expression of AGAT increased steadily across the second half of pregnancy, although GAMT mRNA expression was relatively low until 34 days gestation (term is 38–39 days). In the fetal kidney and liver, AGAT and GAMT mRNA and protein expression were also relatively low until 34–37 days gestation. Between mid-gestation and term, neither AGAT or GAMT mRNA or protein could be detected in the placenta.ConclusionOur results suggest that in the spiny mouse, a species where, like the human, considerable organogenesis occurs before birth, there appears to be a limited capacity for endogenous creatine synthesis until approximately 0.9 of pregnancy. This implies that a maternal source of creatine, transferred across the placenta, may be essential until the creatine synthesis and transport system matures in preparation for birth. If these results also apply to the human, premature birth may increase the risk of creatine deficiency.