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Digital ulcers (DU) are one of the most common and debilitating manifestations of vasculopathy in systemic sclerosis (SSc). Their prevention is important in order to improve patients' outcome and as a result of the economic impact they have on society. Randomised controlled studies have demonstrated that bosentan, an endothelin receptor antagonist, reduces the appearance of new DU. The aim of this retrospective study was to evaluate the occurrence of DU in a group of patients receiving long-term bosentan treatment for pulmonary arterial hypertension associated with SSc (PAH-SSc). Patients with PAH-SSc and treated with bosentan for at least 6 months ( n = 30) were evaluated. Thirty patients with SSc not treated with bosentan, but matched for sex, age, disease duration and cutaneous form of SSc, were considered as a control group. The occurrence of DU, defined as loss of tissue of varying degrees in the epidermis, dermis and subcutaneous tissue, was determined in the bosentan-treated and untreated groups. Mean duration of bosentan treatment was 3.6 years. DU were detected in six patients in the bosentan-treated group (20.0 %) and 16 patients (53.3 %) in the untreated group ( p = 0.0015). There were no significant differences in demographic or clinical characteristics between patients with or without DU at study end. The occurrence of DU in patients with PAH-SSc receiving long-term bosentan treatment was significantly lower than in untreated patients. The results from this long-term observational study provide valuable information on management of patients with PAH-SSc. [ABSTRACT FROM AUTHOR]

Abstract: In the framework of a research program to investigate air staging applied to swirling flames, an experimental investigation aimed at studying pollutant emissions is reported. Staged combustion is accepted as an effective way to reduce nitrogen oxides in gas turbine combustors and, in the present study, is applied to a swirled flame fueled by natural gas, to analyze the potential for further reducing nitrogen oxides emissions in a coaxial, non-premixed combustor under overall lean conditions. The results indicate that the full benefits of air staged combustion in swirling flames depend mainly on the method of fuel injection. The most common method of axial injection of a premixed jet into a co-axial swirling airflow does not realize the required fast mixing. By radial injection of the premixed first stage in the secondary co-axial airflow, more efficient and faster centrifugal mixing is achieved, and hence shorter residence time and higher combustion intensity. This fuel injection strategy results in a more stable flame and dramatic reduction of NO x emissions when the first stage equivalence ratio is approaching the stoichiometric value. Still photographs of the flame and isothermal flow patterns are also reported to help correlate flame morphology and mixing features with nitrogen oxides emission. [Copyright &y& Elsevier]

Background Pulmonary arterial hypertension (PAH) is a life-threatening and debilitating complication of several connective tissue diseases. We aimed to evaluate the effects of long-term treatment with bosentan, an oral dual endothelin ETA/ETB receptor antagonist, in a cohort of patients with PAH related to connective tissue diseases. Material and methods In the present prospective, noncontrolled study, 13 patients (nine with systemic sclerosis, two with systemic lupus erythematosus, one with mixed connective tissue disease and one with overlap syndrome including scleroderma and myositis), mostly nonresponders to prostanoids therapy, were treated for 1 year with bosentan. Cardiac haemodynamics and the diagnosis of PAH were performed by Doppler ultrasound examination. Exercise capacity was assessed by 6-min walking test at baseline and at 3, 6 and 12 months of therapy. Results During bosentan treatment, progressive improvement of exercise capacity was observed. Walk distance increased in seven patients, remained unchanged in three and slightly decreased in three patients. A progressive significant decrease of right ventricular systolic pressure was also observed, whereas pulmonary artery mean pressure remained unchanged. Adverse effects related to bosentan (elevation of hepatic aminotransferases) were noted in two patients. Conclusion Long-term treatment with bosentan was effective in improving exercise capacity and pulmonary haemodynamics in patients with PAH related to connective tissue diseases. [ABSTRACT FROM AUTHOR]

Abstract: The effects of hydrogen addition on a lean non-premixed natural gas swirl-stabilized flame were investigated. Fuel mixtures containing a volumetric fraction of hydrogen ranging from 0% up to 100% were burnt at ambient pressure with swirled air within a quartz chamber in a co-flow configuration. Tests were carried out keeping the sum of the volumetric fuels flow rate constant; thus, the fuel mixture mass flow rate, input thermal power and equivalence ratio decreased as hydrogen fraction was increased. The use of hydrogen-enriched natural gas mixtures allowed the burner to operate at overall leaner stable conditions as compared to the case of burning natural gas only; however, an increase in soot, and CO has also been observed. The flame structure was analyzed by still-color photographs and laser sheet visualization; laser Doppler velocimetry (LDV) and thermocouples were used to analyze the flow field and temperature distributions. Measurements of CO and were obtained by probing the exhaust gases and using gas analyzers, while soot was directly identified by the yellow luminosity in the flame photographs and estimated through spectral analysis of spontaneous flame emission. The present results revealed that hydrogen addition produced: (1) a shorter and narrowed blue flame located closer to the burner head, (2) a central highly luminous yellow plume extending above the visible blue zone, (3) a deeper fuel jet penetration inside the recirculating bubble, and (4) a monotonic increase of both CO and emissions for fractions ranging from 0% up to 80%. The latter behavior may be due to quenching of CO oxidation, related to the reduction in the size of the reaction zone, while the temperature increase observed near the flame front and close to the burner head promote the thermal production. The experimental results revealed that hydrogen addition extended the stability limits of a conventional natural gas non-premixed burner and evidenced a significant change in both the flame structure and the flow field. Improved fuel mixture injection strategies should be explored to improve mixing and minimize pollutant production, without affecting flame stability. [Copyright &y& Elsevier]

Purpose: To assess responsive neurostimulation (RNS) efficacy in pediatric patients with drug-resistant epilepsy, comparing response (≥ 50% reduction in seizure frequency) rates between patients with two or fewer seizure foci and those with multifocal or generalized epilepsy. This study seeks to address the gap in knowledge regarding RNS effectiveness in pediatric populations. Methods: A systematic review and meta-analysis included data from PubMed, Embase, and Web of Science through November 2023, including 17 retrospective studies and a case series of 24 patients from our practice for a total of 105 aggregated patients. The inclusion criteria of patients were age ≤ 18 and diagnosis of DRE. Exclusion criteria were nonhuman subjects and cases where RNS was not utilized to treat DRE. Study inclusion criteria were detailing the use of RNS and comparing patients with ≤ 2 foci with other focalities. Study exclusion criteria were failure to specify RNS lead placement or type of epilepsy. The risk of bias was assessed using the ROBINS-I tool for all non-randomized studies. Effect sizes and variances were aggregated to provide a comprehensive measure of RNS efficacy, and heterogeneity among the studies was assessed using I2 statistics and Cochran's Q test to evaluate the consistency of the findings. Statistical analyses were conducted using IBM SPSS. We analyzed demographics, epilepsy history, treatment outcomes, and RNS details using descriptive and inferential statistics, including Wilcoxon-Mann–Whitney, Fisher's exact, and chi-squared tests. This systematic review was not registered. Results: Seventeen retrospective studies and a single-institution case series, encompassing 105 pediatric patients, were analyzed. Effect sizes and confidence intervals were calculated to quantify treatment effects. Analyses revealed that RNS reduces seizure frequency across a spectrum of pediatric epilepsy syndromes, irrespective of the seizures' focal, multifocal, or generalized origins. The effectiveness of RNS was not influenced by the patient's sex, age at epilepsy onset, or presence of neurological and psychiatric comorbidities. Prior vagus nerve stimulation surgery and the presence of an epileptic syndrome were factors associated with a lower likelihood of near-complete seizure remission with RNS, underscoring the complexities of treating patients with generalized epilepsies or previous interventional failures. The necessity of further research into individualized surgical strategies for patients was underscored by the mixed results of comparisons of electrode characteristics with responder rates. Limitations of our study include its reliance on retrospective studies, which introduces potential bias and limits the ability to infer causality. Discussion: RNS is a safe and effective treatment in pediatric patients with DRE across demographic, comorbidity, and focality variability. FDA age and focality restrictions, along with patient and physician hesitancy, may be limiting the potential for effective treatment of pediatric DRE with RNS. Prospective randomized trials are recommended to validate these findings. [ABSTRACT FROM AUTHOR]

Abstract. The clinical and physiologic features of 28 infants with Pierre Robin syndrome and those of 20 infants with various types of nasal obstruction were reviewed to determine whether different causes of upper airway obstructure may lead to a common syndrome. The patients had no significant differences in distribution of main clinical manifestations. Their features included cyanosis with respiratory distress, apneic spells, oropharyngeal dysphagia, vomiting, failure to thrive, cot pulmonale, brain damage, and sudden death during sleep. The common physiologic manifestation appeared to be an oropharyngeal obstruction caused by glossoptosis, which occurred mainly during wakefulness. Upper airway obstruction led to hypoxemia, which, in many instances, was not associated with hypercapnia and was not relieved by oxygen administration. It is concluded that regardless of a specific cause, any airway obstruction that results in a decreased inspiratory pressure overcoming the airway maintaining genioglossus action causes a glossoptosisapnea syndrome. [ABSTRACT FROM AUTHOR]

• Initial region (up to 2.5D) of a swirling unconfined jet investigated by Stereo PIV at Re = 21,800. • Proper orthogonal decomposition and phase averaging used to unveil the coherent structure. • Coherent structure composed by two co-winding helical vortices, fades away at about x/D = 1.5. • 3D structure reconstructed using iso-contours of phase averaged swirling strength. • 3D structure composed by two helical vortices both counter winding respect to the swirl direction. This work is focused on the near-exit region of a round isothermal free swirling jet to characterize the effect of swirl on the flow field and dominant coherent structures. Most of the work in this field investigated jets produced by vane swirl generators, whereas in our case an axial plus tangential swirl generator without a center-body was used. Stereoscopic PIV has been employed to capture the instantaneous flow field for Reynolds number equal to 21,800 and two swirl levels (0 and 1.4). A proper orthogonal decomposition (POD) applied to the instantaneous velocity vector fields allowed to identify the dominant flow structures associated with the precessing vortex core (PVC). The time coefficients of the most energetic first two POD modes were used to reconstruct the phase of the fluctuating motion in the swirling flow. The phase information was used to conditionally average the instantaneous velocity fields and swirl strength maps; this allowed to reconstruct the 3D structure of the PVC from the 2D data. Overlapping phase slots were used to improve the quality of the reconstructed 3D structure. The minima of negative swirling strength revealed the presence of two co-winding helical structures located in the inner and outer shear layers. The helical structures wind opposite to the base flow rotation and disappear at an axial location of approximately x / D = 1.5. Detailed analysis of the mean, phase averaged and POD modes velocity fields are also reported to further highlight the flow field features. The third and fourth transverse POD modes evidenced the presence of a m = 2 azimuthal wave buried in the dominant m = 1 wave; such wave belong to a vortex pair superimposed to the precessing vortex core. Close to the nozzle exit, the analysis of the coherent and random parts of the velocity fluctuations evidenced that the PVC slightly increases the stochastic velocity fluctuations, but the latter resulted to be more isotropic respect to the non-swirling case. Our results put into evidence that the combined application of PIV, POD and phase averaging techniques can provide detailed observations of coherent fluctuations induced by vortex precession. The latter can help to improve the understanding of PVC and VB and to find possible strategies to prevent/control their formation. Finally, they can be of interest to develop numerical models for the simulation of these complex flows. [ABSTRACT FROM AUTHOR]

Comments on an article published by Arnestad and colleagues which deals with dummy sucking and sudden infant death syndrome (SIDS). Hypothesis about dummies; Prevention of glossoptosis-apnoea in infants through non-nutritive sucking; Discussion on glossopexy as another prophylactic measure against sudden infant death syndrome.

Abstract: A method for the determination of cadmium and lead in apple and pear fruit juices by stripping chronopotentiometry (SCP) is described. The results obtained after previous digestion of the sample with concentrated sulphuric acid and dry-ashing (sample pretreatment procedure “A”) and after a treatment with concentrated hydrochloric acid followed by heating in hot water bath (sample pretreatment procedure “B”) were compared. The sample pretreatment procedures were tested on real fruit juice samples and all data confirmed that the efficiency of procedure A was greater than procedure B. In particular, for samples treated with procedure A, good linearity was obtained in the range of examined concentration as is shown by the determination coefficients that were 0.998 (n =4) for cadmium and 0.996 (n =4) for lead. Recoveries of 86–104% for cadmium and of 87–102% for lead were obtained from a sample spiked at different levels. The accuracy was also evaluated by means of a matching reference sample of spiked skim milk powder (BCR 150—Community Bureau of Reference) to prove the reliability of the method. The detection limits were 2.0ngg−1 for cadmium and 4.8ngg−1 for lead. The relative standard deviations (mean of nine determinations), evaluated on a real sample, were 7.8% and 6.5% respectively. The average content was in the range not detectable–3.0ngg−1 for cadmium and 8.2–21.3ngg−1 for lead. [Copyright &y& Elsevier]

Utrophin is highly homologous and structurally similar to dystrophin, and in gene delivery experiments in mdx mice was able to functionally replace dystrophin. We performed mini-utrophin gene transfer in Golden Retriever dogs with canine muscular dystrophy (CXMD). Unlike the mouse model, the clinicopathological phenotype of CXMD is similar to that of Duchenne muscular dystrophy (DMD). We injected an adenoviral vector expressing a synthetic utrophin into tibialis anterior muscles of newborn dogs affected with CXMD and examined transgene expression by RNA and protein analysis at 10, 30 and 60 days postinjection in cyclosporin-treated and -untreated animals. Immunosuppression by cyclosporin was required to mitigate the immune response to viral and transgene antigens. RT-PCR analysis showed the presence of the exogenous transcript in the muscle of cyclosporin-treated and -untreated animals. The transgenic utrophin was efficiently expressed at the extrajunctional membrane in immunosuppressed dogs and this expression was stable for at least 60 days. We found reduced fibrosis and increased expression of dystrophin-associated proteins (DAPs) in association with muscle areas expressing the utrophin minigene, indicating that mini-utrophin can functionally compensate for lack of dystrophin in injected muscles. For this reason, utrophin transfer to dystrophin-deficient muscle appears as a promising therapeutic approach to DMD.Gene Therapy (2003) 10, 750-757. doi:10.1038/sj.gt.3301941 [ABSTRACT FROM AUTHOR]

• Automatic detection of flow structure within schlieren images of supersonic flows. • Accurate Mach number measurements in moderately supersonic flows. • Accurate measurement of position and slope of simple waves and oblique shocks. • Quantitative application of schlieren technique in non-ideal compressible flows. • Experimental characterization of highly non-ideal supersonic flows. This paper presents a technique to automatically detect flow structures recorded in schlieren images of supersonic flows. The method provides position and local slope of the detected lines. Salient flow structures considered are shock waves, expansion fans and Mach waves. If the local flow direction is known, the technique provides local Mach number measurement. Moreover, the peculiarities of schlieren technique make the algorithm suitable for Mach measurements in flows where direct velocity measurements are challenged by difficult insemination and for which calibrated aerodynamic pressure probes are not available. The technique is applied to two test cases. In the first case study, the local Mach number is measured at the axis of a supersonic nozzle operated with siloxane vapor MDM. In the second test case, supersonic flow of MDM was analyzed around a diamond shaped airfoil providing the Mach number upstream/downstream oblique shocks/expansion fans and the slope of oblique shocks/fan edges. [ABSTRACT FROM AUTHOR]

Reports that surgery for radial artery pseudoaneurysm in children may be followed by growth retardation of the hand. Effect of inadequate blood flow; Color Doppler imaging; Non-operative management of uncomplicated pseudoaneurysm.

The article presents an abstract of the medical research paper "Long Term Neuroprotective Effects of Glycosaminoglycan-IGF-I Cotreatment in the Neuromuscular Disease of the Mnd Mouse." The paper shows that cotreatment of m/m mutant mice with GF-I and glycosaminoglycans (GAGs) prevented the onset of neuromuscular abnormalities, twitch tension loss, motor neuron decrease and the forelimb grip strength reduction.