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Radiosonde data are valuable to the research community because they provide observations for multiple decades and can be used to validate model output. However radiosonde data often suffer from quality issues, which has undermined their credibility. Therefore, corrections for biases and changepoints are needed to remedy the situation. Homogenization of monthly radiosonde specific humidity (q) from the 1970s to the present has been performed on selected stations over the Southwest Pacific (SWP) at three pressure levels (i.e. 850, 700 and 500 hPa). A three-step procedure involving (1) adjustments for two sampling biases, (2) detecting secular changepoints (i.e. discontinuities) using both statistical techniques and metadata validation, and (3) an innovative break size estimate approach, has been implemented to achieve this aim. In the last step, a discontinuity-free pseudo-q is constructed from saturated specific humidity qs which itself is derived from an already homogenized temperature (T) time series. This pseudo-q serves as a reference that not only distinguishes artificial from natural changepoints but also helps to estimate the magnitudes of the discontinuity. On the decadal time scale, the adjusted q (qadj) exhibits spatially more consistent moistening at the 850 hPa level over most of the region and a contrast at 500 hPa between the moistening in the tropics and a drying in the subtropical South Pacific. Mean regional trend estimates are ∼1.8% (850 hPa), −0.2% (700 hPa) and 1.3% (500 hPa) per decade. A climatological comparison with the three latest reanalysis products – CFSR, ERA-Interim and MERRA, suggests the reanalyses have significant negative biases over Southeast Asia (SEA) at all three levels. Over Australia the biases are negative at 850 hPa while positive at 500 hPa. The reanalysis products tend to be more similar among themselves in the estimates of q, as compared to the radiosonde measurements of q and qadj. The homogenized radiosonde q, when assimilated into reanalysis, is likely to lead to a more realistic model of the hydrological cycle.

As part of an international intercomparison project, the weak temperature gradient (WTG) and damped gravity wave (DGW) methods are used to parameterize large-scale dynamics in a set of cloud-resolving models (CRMs) and single column models (SCMs). The WTG or DGW method is implemented using a configuration that couples a model to a reference state defined with profiles obtained from the same model in radiative-convective equilibrium. We investigated the sensitivity of each model to changes in SST, given a fixed reference state. We performed a systematic comparison of the WTG and DGW methods in different models, and a systematic comparison of the behavior of those models using the WTG method and the DGW method. The sensitivity to the SST depends on both the large-scale parameterization method and the choice of the cloud model. In general, SCMs display a wider range of behaviors than CRMs. All CRMs using either the WTG or DGW method show an increase of precipitation with SST, while SCMs show sensitivities which are not always monotonic. CRMs using either the WTG or DGW method show a similar relationship between mean precipitation rate and column-relative humidity, while SCMs exhibit a much wider range of behaviors. DGW simulations produce large-scale velocity profiles which are smoother and less top-heavy compared to those produced by the WTG simulations. These large-scale parameterization methods provide a useful tool to identify the impact of parameterization differences on model behavior in the presence of two-way feedback between convection and the large-scale circulation.

As part of an international intercomparison project, a set of single column models (SCMs) and cloud-resolving models (CRMs) are run under the weak temperature gradient (WTG) method and the damped gravity wave (DGW) method. For each model, the implementation of the WTG or DGW method involves a simulated column which is coupled to a reference state defined with profiles obtained from the same model in radiative-convective equilibrium. The simulated column has the same surface conditions as the reference state and is initialized with profiles from the reference state. We performed systematic comparison of the behavior of different models under a consistent implementation of the WTG method and the DGW method and systematic comparison of the WTG and DGW methods in models with different physics and numerics.\ud \ud CRMs and SCMs produce a variety of behaviors under both WTG and DGW methods. Some of the models reproduce the reference state while others sustain a large-scale circulation which results in either substantially lower or higher precipitation compared to the value of the reference state. CRMs show a fairly linear relationship between precipitation and circulation strength. SCMs display a wider range of behaviors than CRMs. Some SCMs under the WTG method produce zero precipitation. Within an individual SCM, a DGW simulation and a corresponding WTG simulation can produce different signed circulation.\ud \ud When initialized with a dry troposphere, DGW simulations always result in a precipitating equilibrium state. The greatest sensitivities to the initial moisture conditions occur for multiple stable equilibria in some WTG simulations, corresponding to either a dry equilibrium state when initialized as dry or a precipitating equilibrium state when initialized as moist. Multiple equilibria are seen in more WTG simulations for higher SST. In some models, the existence of multiple equilibria is sensitive to some parameters in the WTG calculations.

INTRODUCTION Fibreoptic bronchoscopy (FB) is an important diagnostic examination in paediatric pulmonology. In 2002 the Paediatric Pulmonology and Allergy Club undertook a retrospective study to establish the current status of fibreoptic bronchoscopy among its members. METHODS In 2001 sixty five paediatric pulmonologists carried out an average of 116 examinations (+/- 111) in 35 paediatric centres. FB was performed either in an operating theatre (15 centres), a dedicated bronchoscopy suite (6 centres) or an endoscopy suite shared with gastro-enterologists (7 centres). Other examinations were performed in areas dedicated to, or associated with intensive care. General anaesthesia was routinely used in 18 centres. The others used sedation including an equimolar mixture of oxygen and nitrous oxide in 14 centres. Ten centres performed less than 50 examinations, 12 between 51 and 100, 4 between 101 and 200 and 8 centres more than 200 in the year. Seventy two per cent of the children were less than 6 years old. The washing and disinfection procedures were manual in 20 centres and automatic in 15. RESULTS Three principal indications were reported: persistent wheezing, suspicion of a foreign body and ventilatory difficulties. Cough, desaturation and fever were the most frequently reported side effects. CONCLUSIONS This is the first survey in paediatric pulmonology in France. It shows a wide variation in the practice of fibreoptic bronchoscopy in children.

Unilateral primitive agenesia of pulmonary artery is a rare congenital disorder. Experience of three hospital-based pulmonology pediatric units including eight children (three boys and five girls) with such anomaly is reported (11 years median follow-up, range 6 months to 10 years). Median age at diagnosis was 4 years. Clinical features included recurrent respiratory tract infections (75%), effort dyspnea (50%) and, curiously, asthmatic symptoms (75%). Diagnosis was evoked on chest X rays and confirmed by angiography in all cases. Agenesis of the right pulmonary artery was more frequent (five cases). Abnormal vascular ring was associated in two cases of agenesis of the left pulmonary artery. Pulmonary function tests were performed in six children, with bronchial obstruction in two. Regular clinical follow-up, up to adult age in four cases, showed no complication, such as hemoptysis or pulmonary hypertension in our patients.

We retrospectively analyzed the long-term outcome of idiopathic pulmonary hemosiderosis (IPH) in 15 children. IPH started at a mean age of 5 years, and the mean duration of follow-up was 17.2 years (range, 10-36 yr). Four patients developed immune disorders, 3 cases of rheumatoid polyarthritis or rheumatoid polyarthritis-like diseases and 1 case of celiac disease. Respiratory outcome showed that 3 patients had severe symptoms: 2 patients developed severe pulmonary fibrosis resulting in major chronic respiratory insufficiency, and 1 patient had severe asthma. Twelve patients (80%) had mild or no respiratory problems and were able to lead a normal life. According to chest X-ray and pulmonary function test data, 4 patients had normal chest X-ray and no evidence of restrictive syndrome, 6 patients had an interstitial pattern on chest X-ray and evidence of restrictive pattern, 1 patient had an interstitial pattern but normal lung function, and 1 patient had a normal chest X-ray but evidence of mixed obstructive and restrictive pattern. Our results show that long-term survival is possible in patients with IPH. Factors of poor prognosis seem to be the presence of antineutrophil cytoplasm antibodies (ANCA) or other autoantibodies. No other clinical or biological predictive factors for prolonged survival were found.

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RATIONALE: New treatment strategies are needed to improve airway clearance and reduce the morbidity and the time burden associated with cystic fibrosis (CF). OBJECTIVES: To determine whether long-term treatment with inhaled mannitol, an osmotic agent, improves lung function and morbidity. METHODS: Double-blind, randomized, controlled trial of inhaled mannitol, 400 mg twice a day (n = 192, "treated" group) or 50 mg twice a day (n = 126, "control" group) for 26 weeks, followed by 26 weeks of open-label treatment. MEASUREMENTS AND MAIN RESULTS: The primary endpoint was absolute change in FEV(1) from baseline in treated versus control groups, averaged over the study period. Secondary endpoints included other spirometric measurements, pulmonary exacerbations, and hospitalization. Clinical, microbiologic, and laboratory safety were assessed. The treated group had a mean improvement in FEV(1) of 105 ml (8.2% above baseline). The treated group had a relative improvement in FEV(1) of 3.75% (P = 0.029) versus the control group. Adverse events and sputum microbiology were similar in both treatment groups. Exacerbation rates were low, but there were fewer in the treated group (hazard ratio, 0.74; 95% confidence interval, 0.42-1.32; P = 0.31), although this was not statistically significant. In the 26-week open-label extension study, FEV(1) was maintained in the original treated group, and improved in the original control group to the same degree. CONCLUSIONS: Inhaled mannitol, 400 mg twice a day, resulted in improved lung function over 26 weeks, which was sustained after an additional 26 weeks of treatment. The safety profile was also acceptable, demonstrating the potential role for this chronic therapy for CF. Clinical trial registered with www.clinicaltrials.gov (NCT 00630812).

A simple framework to study the sensitivity of atmospheric boundary layer (ABL) models to the large-scale conditions and forcings is introduced. This framework minimizes the number of parameters necessary to describe the large-scale conditions, subsidence, and radiation. Using this framework, the sensitivity of the stationary ABL to the large-scale boundary conditions [underlying sea surface temperature (SST) and overlying humidity and temperature in the free troposphere] is investigated in large-eddy simulations (LESs). For increasing SST or decreasing free-tropospheric temperature, the LES exhibits a transition from a cloud-free, well-mixed ABL stationary state, through a cloudy, well-mixed stationary state and a stable shallow cumulus stationary state, to an unstable regime with a deepening shallow cumulus layer. For a warm SST, when increasing free-tropospheric humidity, the LES exhibits a transition from a stable shallow cumulus stationary state, through a stable cumulus-under-stratus stationary state, to an unstable regime with a deepening, cumulus-under-stratus layer. For a cool SST, when increasing the free-tropospheric humidity, the LES stationary state exhibits a transition from a cloud-free, well-mixed ABL regime, through a well-mixed cumulus-capped regime, to a stratus-capped regime with a decoupling between the subcloud and cloud layers. This dataset can be used to evaluate other ABL models. As an example, the sensitivity of a bulk model based on the mixing-line model is presented. This bulk model reproduces the LES sensitivity to SST and free-tropospheric temperature for the stable and unstable shallow cumulus regimes, but it is less successful at reproducing the LES sensitivity to free-tropospheric humidity for both shallow cumulus and well-mixed regimes.