bluuebunny/crossref_metadata_2025_split huggingface dataset:
Climatology of Surface Meteorology, Surface Fluxes, Cloud Fraction, and Radiative Forcing over the Southeast Pacific from Buoy Observations
Authors: Ghate Virendra P. , Albrecht Bruce A. , Fairall Christopher W. , Weller Robert A. 
Published: June 2009

Abstract
A 5-yr climatology of the meteorology, including boundary layer cloudiness, for the southeast Pacific region is presented using observations from a buoy located at 20°S, 85°W. The sea surface temperature and surface air temperature exhibit a sinusoidal seasonal cycle that is negatively correlated with surface pressure. The relative humidity, wind speed, and wind direction show little seasonal variability. But the advection of cold and dry air from the southeast varies seasonally and is highly correlated with the latent heat flux variations. A simple model was used to estimate the monthly cloud fraction using the observed surface downwelling longwave radiative flux and surface meteorological parameters. The annual cycle of cloud fraction is highly correlated to that of S. A. Klein: lower-tropospheric stability parameter (0.87), latent heat flux (−0.59), and temperature and moisture advection (0.60). The derived cloud fraction compares poorly with the International Satellite Cloud Climatology Project (ISCCP)-derived low-cloud cover but compares well (0.86 correlation) with ISCCP low- plus middle-cloud cover. The monthly averaged diurnal variations in cloud fraction show marked seasonal variability in the amplitude and temporal structure. The mean annual cloud fraction is lower than the mean annual nighttime cloud fraction by about 9%. Annual and diurnal cycles of surface longwave and shortwave cloud radiative forcing were also estimated. The longwave cloud radiative forcing is about 45 W m−2 year-round, but, because of highly negative shortwave cloud radiative forcing, the net cloud radiative forcing is always negative with an annual mean of −50 W m−2.
Dissecting the Pressure Field in Tidal Flow past a Headland: When Is Form Drag “Real”?
Authors: Warner Sally J. , MacCready Parker 
Published: June 2009

Abstract
In the few previous measurements of topographic form drag in the ocean, drag that is much larger than a typical bluff body drag estimate has been consistently found. In this work, theory combined with a numerical model of tidal flow around a headland in a channel gives insight into the mechanisms that create form drag in oscillating flow situations. The total form drag is divided into two parts: the inertial drag, which is derived from a local potential flow solution, and the separation drag, which accounts for flow features such as eddies. The inertial drag can have a large magnitude, yet it cannot do work on the flow because its phase is in quadrature with the velocity. The separation drag has a magnitude that is nearly equal to the bluff body drag and accounts for all of the energy removed from the flow by the topography. In addition, the dependence of the form drag on the tidal excursion distance and the aspect ratio of the headlands were determined with a series of numerical experiments. This theory explains why form drag can be so large in the ocean, and it provides a method for separating the pressure field into the parts that can and cannot extract energy from the flow.
Differences in Draft Core Statistics from the Wet to Dry Spell over Gadanki, India (13.5°N, 79.2°E)
Authors: Rao T. Narayana , Uma K. N. , Satyanarayana T. Mohan , Rao D. Narayana 
Published: June 2009

AbstractThe Indian mesosphere–stratosphere–troposphere (MST) radar observations during the passage of 37 convective systems are utilized to investigate the characteristics of vertical air velocity w in different convection categories (shallow, deep, and decaying) and also the differences in draft core statistics from the wet to dry spell. The radar and optical rain gauge measurements show pronounced differences in core statistics (in terms of their vertical structure, draft strength, size, number, and the elevation angle) and surface rainfall characteristics from the dry to wet spell. The shallow convective cores are preponderant in the dry spell. Composite w profiles, retrieved from all deep cases and also from individual convection cases, depict an upper-tropospheric peak in the wet spell and a bimodal distribution (peaks at 5 and 11–13 km) in the dry spell, illustrating that they are characteristic features of wet and dry spells. The average vertical extents of the cores are nearly equal (about 8 km) in both spells of the monsoon; however, the core-base (and top) altitudes are different. In both wet and dry spells, the composite w profile for all cores show similar vertical variation to that of for updraft cores, while the composite w for downdraft cores do not show much variation with altitude, indicating that the updraft cores dictate the vertical structure of composite w. The core size varies considerably (a factor of 2) with altitude in both spells of the monsoon. Although nearly equal in the lower troposphere in both phases of the monsoon, the core size is larger by 1–2 km in the dry spell in the middle and upper troposphere. Consistent with the longer lifetime (bigger core size) of cores in the dry spell, the cores are more inclined (with a mean elevation angle of 30°) in the dry spell. The surface rainfall distribution is wider and has large number of intense rainfall rates in the wet spell. The mean rainfall rate for the wet spell is also larger by a factor of 2, consistent with earlier studies.
Surgical Correction of Limb Malalignment for Instability of the Patella
Authors: Paulos Lonnie , Swanson Stephen C. , Stoddard Gregory J. , Barber-Westin Sue 
Published: June 2009

Background Although patients considered “successful” at longer-term follow-up no longer exhibited patellar instability, those with more severe malalignment issues had other, gradually worsening symptoms such as activity-related pain, crepitation, swelling with activities, and pain with weather changes. Hypothesis Improvement of patellar tracking by correction of the tubercle-sulcus angle and related ligament deficiencies will result in good to excellent results, regardless of the technique employed. Study Design Cohort study; Level of evidence, 3. Methods Twenty-five patients with dislocating patellae and significant lower leg deformity were treated; 12 patients (group 1) underwent a derotational high tibial osteotomy and 13 patients (group 2) underwent an Elmslie-Trillat-Fulkerson proximal-distal realignment. All were prospectively evaluated a minimum of 24 months postoperatively with a physical examination, validated outcome questionnaires, radiographs, and computerized axial tomography scans. Postoperative 3-dimensional bilateral gait analyses were performed on all subjects walking on a 3-dimensional force treadmill to measure stance kinematics, foot progression angle, knee flexion, knee valgus-varus, hip flexion, and patella angle. Contralateral limbs with similar preoperative alignment were used as controls. Results Group 1 patients significantly improved over their preoperative status in all primary subjective and functional outcome parameters, and were significantly better than group 2 patients. Group 2 patients improved, but not to the degree of group 1 patients. Gait analysis revealed group 1 patients had more symmetrical gait patterns, with less variability and less compensatory gait changes, than group 2 patients. Conclusion The original hypothesis proved to be incorrect. The simultaneous correction of ligament imbalance, excessive tubercle-sulcus angle, and lower limb torsional deformity produced significantly better results than conventional proximal-distal realignment.
Diagnosis of tuberculosis: principles and practice of using interferon-γ release assays (IGRAs)
Authors: Lalvani A. , Thillai M. 
Published: June 2009

Educational aimsTo provide an overview of T-cell interferon-γrelease assays (IGRAs) used for detection of tuberculosis (TB) infection.To outline how these tests can be used in clinical practice for the assessment of latent TB infection (LTBI) and active TB.SummaryOne in three people worldwide are infected withMycobacterium tuberculosis; the vast majority have latent infection. Tracking this latent reservoir is the cornerstone of TB control and prevention in the developed world [1]. But standard tools for diagnosis and prevention are more than 100 years old and inadequate to control the global TB epidemic [2]. However, the last decade has witnessed a major advance in the diagnosis ofM. tuberculosisinfection [3–5]. T-cell IGRAs are the first practical output of a decade of reinvigorated basic science research into TB and are now revolutionising diagnosis and screening of LTBI.
The pathogenesis of acute infection in COPD
Authors: Anzueto A. 
Published: June 2009

Educational aimsTo give an overview of the types of infectious agents involved in causing acute exacerbations of chronic obstructive pulmonary disease (COPD).To outline the mechanisms through which infectious agents drive exacerbations.To introduce the concept that mixed infections may increase the severity of exacerbations.SummaryA number of virulence factors have been associated with bacterial pathogens' propensity to cause exacerbations, and the genetic basis for these has begun to be examined. In addition, the acquisition of new strains of some bacteria has been associated with exacerbations. Viral nucleic acids are detected in about half of exacerbations, and several viruses are implicated, in particular rhinovirus. The manner in which these and other pathogens, individually and collectively, interact with the host merits further scrutiny if the prevention and treatment of acute COPD exacerbations are to be improved.
COPD guidelines in relation to infections: a critical analysis
Authors: Torres A. 
Published: June 2009

Educational aimsTo define the importance of exacerbations in COPD and chronic bronchitis.To assess current guidelines for the treatment of COPD exacerbations.To outline current antibiotic treatments and treatment periods for exacerbations.SummaryChronic obstructive pulmonary disease (COPD) exacerbations have been associated with an increased risk of mortality and currently available therapies for exacerbations show only limited beneficial effects. Bacterial infections caused by pathogens are the predominant cause of acute exacerbations in COPD and chronic bronchitis. Current guidelines suggest a correlation between forced expiratory volume in 1 s (FEV1) and the type of infecting pathogen and that purulence of sputum is one of the most important factors associated with the presence of a bacterial infection. Antibiotics are recommended for patients with exacerbations and sputum purulence. However, resistance to antibiotics is increasing, especially in southern Europe. To reduce the risk of resistance, shorter treatment periods can be implemented for patients with mild-to-moderate exacerbations.
Patient–ventilator interaction during noninvasive ventilation: practical assessment and theoretical basis
Authors: Nava S. , Carlucci A. , Ceriana P. 
Published: June 2009

SummarySynchrony refers to the agreement between the patient's own (neural) and the ventilator's (mechanical) inspiratory and expiratory time. Noninvasive ventilation (NIV) is a semi-open system, which means air leaks are common. This greatly affects patient synchrony. In addition to air leaks, there are other factors that affect patient–ventilator mismatching. This review will focus on NIV and on the main forms of asynchrony and mismatching, their causes and methods to eventually identify these problems from the flow and pressure signals.
Noninvasive ventilation as an adjunct to exercise training in patients with chronic respiratory disease
Authors: Piper A.J. , Menadue C. 
Published: June 2009

Educational aimsTo describe the potential benefits of noninvasive positive-pressure ventilation (NIV) as an adjunct to exercise training in selected patients with chronic obstructive pulmonary disease (COPD) or chest wall restriction.To outline the mechanisms by which NIV may improve exercise performance in selected patients with COPD or chest wall restriction.To identify characteristics of patients with chronic respiratory disease who are more likely to respond to NIV-assisted training.To highlight major practical considerations for implementing NIV-assisted training in an individual with COPD or chest wall restriction.SummarySevere exertional dyspnoea is a major impediment to physical activity and adversely affects quality of life for many individuals with chronic respiratory disease. Although exercise can improve cardiorespiratory and peripheral muscle responses, training at sufficient intensity and duration may be difficult for the very breathless, deconditioned patient. Consequently, strategies to optimise training for such individuals are gaining interest. NIV is one such option and there is a growing body of evidence outlining its benefits in selected patients. However, the technique is not without its constraints and problems. An understanding of the mechanisms underlying improvements in exercise performance with NIV-assisted training is important in targeting appropriate candidates for intervention and identifying the best therapy to achieve the maximum benefit.
Cross-study analysis of genomic data defines the ciliate multigenic epiplasmin family: strategies for functional analysis in Paramecium tetraurelia
Authors: Damaj Raghida , Pomel Sébastien , Bricheux Geneviève , Coffe Gérard , Viguès Bernard , Ravet Viviane , Bouchard Philippe 
Published: June 2009

AbstractBackgroundThe sub-membranous skeleton of the ciliateParamecium, the epiplasm, is composed of hundreds of epiplasmic scales centered on basal bodies, and presents a complex set of proteins, epiplasmins, which belong to a multigenic family. The repeated duplications observed in theP. tetraureliagenome present an interesting model of the organization and evolution of a multigenic family within a single cell.ResultsTo study this multigenic family, we used phylogenetic, structural, and analytical transcriptional approaches. The phylogenetic method defines 5 groups of epiplasmins in the multigenic family. A refined analysis by Hydrophobic Cluster Analysis (HCA) identifies structural characteristics of 51 epiplasmins, defining five separate groups, and three classes. Depending on the sequential arrangement of their structural domains, the epiplasmins are defined as symmetric, asymmetric or atypical. The EST data aid in this classification, in the identification of putative regulating sequences such as TATA or CAAT boxes. When specific RNAi experiments were conducted using sequences from either symmetric or asymmetric classes, phenotypes were drastic. Local effects show either disrupted or ill-shaped epiplasmic scales. In either case, this results in aborted cell division.Using structural features, we show that 4 epiplasmins are also present in another ciliate,Tetrahymenathermophila. Their affiliation with the distinctive structural groups ofParameciumepiplasmins demonstrates an interspecific multigenic family.ConclusionThe epiplasmin multigenic family illustrates the history of genomic duplication inParamecium. This study provides a framework which can guide functional analysis of epiplasmins, the major components of the membrane skeleton in ciliates. We show that this set of proteins handles an important developmental information inParameciumsince maintenance of epiplasm organization is crucial for cell morphogenesis.
Characterisation of atypical enteropathogenic E. coli strains of clinical origin
Authors: Tennant Sharon M , Tauschek Marija , Azzopardi Kristy , Bigham Andrea , Bennett-Wood Vicki , Hartland Elizabeth L , Qi Weihong , Whittam Thomas S , Robins-Browne Roy M 
Published: June 2009

Abstract

Background
Enteropathogenic E. coli (EPEC) is a prominent cause of diarrhoea, and is characterised in part by its carriage of a pathogenicity island: the locus for enterocyte effacement (LEE). EPEC is divided into two subtypes according to the presence of bundle-forming pili (BFP), a fimbrial adhesin that is a virulence determinant of typical EPEC (tEPEC), but is absent from atypical EPEC (aEPEC). Because aEPEC lack BFP, their virulence has been questioned, as they may represent LEE-positive Shiga toxin-producing E. coli (STEC) that have lost the toxin-encoding prophage, or tEPEC that have lost the genes for BFP. To determine if aEPEC isolated from humans in Australia or New Zealand fall into either of these categories, we undertook phylogenetic analysis of 75 aEPEC strains, and compared them with reference strains of EPEC and STEC. We also used PCR and DNA hybridisation to determine if aEPEC carry virulence determinants that could compensate for their lack of BFP.

Results
The results showed that aEPEC are highly heterogeneous. Multilocus sequence typing revealed that 61 of 75 aEPEC strains did not belong to known tEPEC or STEC clades, and of those that did, none expressed an O:H serotype that is frequent in tEPEC or STEC strains associated with disease. PCR for each of 18 known virulence-associated determinants of E. coli was positive in less than 15% of strains, apart from NleB which was detected in 30%. Type I fimbriae were expressed by all aEPEC strains, and 12 strains hybridised with DNA probes prepared from either bfpA or bfpB despite being negative in the PCR for bfpA.

Conclusion
Our findings indicate that clinical isolates of aEPEC obtained from patients in Australia or New Zealand are not derived from tEPEC or STEC, and suggest that functional equivalents of BFP and possibly type I fimbriae may contribute to the virulence of some aEPEC strains.
Growth and development of the placenta in the capybara (Hydrochaeris hydrochaeris)
Authors: Kanashiro Claudia , Santos Tatiana C , Miglino Maria Angelica , Mess Andrea M , Carter Anthony M 
Published: June 2009

Abstract

Background
The guinea pig is an attractive model for human pregnancy and placentation, mainly because of its haemomonochorial placental type, but is rather small in size. Therefore, to better understand the impact of body mass, we studied placental development in the capybara which has a body mass around 50 kg and a gestation period of around 150 days. We paid attention to the development of the lobulated arrangement of the placenta, the growth of the labyrinth in the course of gestation, the differentiation of the subplacenta, and the pattern of invasion by extraplacental trophoblast.

Methods
Material was collected from six animals at pregnancy stages ranging from the late limb bud stage to mid gestation. Methods included latex casts, standard histology, immunohistochemistry for cytokeratin, vimentin, alpha-smooth muscle actin, and proliferating cell nuclear antigen as well as transmission electron microscopy.

Results
At the limb bud stage, the placenta was a pad of trophoblast covered by a layer of mesoderm from which fetal vessels were beginning to penetrate at folds in the surface. By 70 days, the placenta comprised areas of labyrinth (lobes) separated by interlobular areas. Placental growth resulted predominantly from proliferation of cellular trophoblast situated in nests at the fetal side of the placenta and along internally directed projections on fetal mesenchyme. Additional proliferation was demonstrated for cellular trophoblast within the labyrinth.
Already at the limb bud stage, there was a prominent subplacenta comprising cellular and syncytial trophoblast with mesenchyme and associated blood vessels. At 90 days, differentiation was complete and similar to that seen in other hystricognath rodents. Overlap of fetal vessels and maternal blood lacunae was confirmed by latex injection of the vessels. At all stages extraplacental trophoblast was associated with the maternal arterial supply and consisted of cellular trophoblast and syncytial streamers derived from the subplacenta.

Conclusion
All important characteristics of placental development and organization in the capybara resembled those found in smaller hystricognath rodents including the guinea pig. These features apparently do not dependent on body size. Clearly, placentation in hystricognaths adheres to an extraordinarily stable pattern suggesting they can be used interchangeably as models of human placenta.
Multisegmental spondylitis due to Tropheryma whipplei: Case report
Authors: Spoerl David , Bär Diego , Cooper Julian , Vogt Thomas , Tyndall Alan , Walker Ulrich A 
Published: June 2009

Abstract
We report a patient who presented with inflammatory back pain due to multisegmental spondylitis. Following a vertebral biopsy which failed to detect an infectious organism, the patient was treated with etanercept, a tumor necrosis factor (TNF)-α inhibitor, for suspected undifferentiated spondyloarthritis. The back pain worsened and the spondylitic lesions increased. Only in a vertebral rebiopsy with polymerase chain reaction (PCR) amplification of Tropheryma whipplei, the causative agent of Whipple's disease was identified. Tropheryma whipplei should be considered as a cause of spondylitis even with multisegmental involvement and in the absence of gastrointestinal symptoms. In this clinical setting, routine PCR for Tropheryma whipplei from vertebral biopsies is recommended.
Impaired Glucose-Induced Glucagon Suppression after Partial Pancreatectomy
Authors: Schrader Henning , Menge Bjoern A. , Breuer Thomas G. K. , Ritter Peter R. , Uhl Waldemar , Schmidt Wolfgang E. , Holst Jens J. , Meier Juris J. 
Published: June 2009

Introduction: The glucose-induced decline in glucagon levels is often lost in patients with type 2 diabetes. It is unclear whether this is due to an independent defect in α-cell function or secondary to the impairment in insulin secretion. We examined whether a partial pancreatectomy in humans would also impair postchallenge glucagon concentrations and, if so, whether this could be attributed to the reduction in insulin levels.
Patients and Methods: Thirty-six patients with pancreatic tumours or chronic pancreatitis were studied before and after approximately 50% pancreatectomy with a 240-min oral glucose challenge, and the plasma concentrations of glucose, insulin, C-peptide, and glucagon were determined.
Results: Fasting and postchallenge insulin and C-peptide levels were significantly lower after partial pancreatectomy (P &lt; 0.0001). Likewise, fasting glucagon concentrations tended to be lower after the intervention (P = 0.11). Oral glucose ingestion elicited a decline in glucagon concentrations before surgery (P &lt; 0.0001), but this was lost after partial pancreatectomy (P &lt; 0.01 vs. preoperative values). The loss of glucose-induced glucagon suppression was found after both pancreatic head (P &lt; 0.001) and tail (P &lt; 0.05) resection. The glucose-induced changes in glucagon levels were closely correlated to the respective increments in insulin and C-peptide concentrations (P &lt; 0.01).
Conclusions: The glucose-induced suppression in glucagon levels is lost after a 50% partial pancreatectomy in humans. This suggests that impaired α-cell function in patients with type 2 diabetes may also be secondary to reduced β-cell mass. Alterations in glucagon regulation should be considered as a potential side effect of partial pancreatectomies.