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Line intensities of H2CO are analyzed between 1148.4 and 1192.8 cm-1 by taking into account the Coriolis interaction involving the ν4 and ν6 fundamentals. Finally two intensity parameters can be significantly determined: ∂μy/∂q4=0.0592±0.0018 D and ∂μx/∂q6=0.0772±0.0019 D. From these results, the ‘‘deperturbed’’ band strenghts can be calculated: S04=20.9±1.3 cm‘u-2 atm-1 and S06=38.0±1.9 cm-2 atm-1 at T=297 K. [ABSTRACT FROM AUTHOR]

Spontaneous pneumothorax is one cause of aeronautical unfitness in flight personnel, because of the risk of recurrence in flight, making it an issue of flight safety. Specific treatment is required for fighter pilots, pilots flying single-pilot and pilots in professional training: surgical synthesis via video-thoracoscopy is obligatory from the first episode. Considering the exposure to an accumulation of aeronautical factors that are likely to encourage pneumothorax recurrence in flight, it is apical pleurectomy together with abrasion of the remaining pleura and resection of bullae/blebs that is required for fighter pilots to allow them to recover aeronautical fitness unrestrictedly. For all other categories of flight personnel, treatment is no different from that of the common patient. Knowledge of these treatment specifics is essential, to avoid unnecessary systematic surgical indication for all flight personnel, or jeopardise professional fitness in some of them due to inappropriate treatment., (Copyright © 2010 Elsevier Masson SAS. All rights reserved.)

Introduction: Because of its excellent negative predictive value for diagnosing coronary stenoses, multislice computed tomography (MSCT) may be a way to assess the absence of significant coronary stenosis. We discussed its place in aeromedical decision-making for aircrew members with a low level of cardiovascular risk factors and acquired left bundle branch block (LBBB)., Methods and Results: During the period 2002-2004, 12 male aircrew members (mean age: 42.9 yr) with acquired LBBB were admitted to our cardiovascular and aeronautical department. The exploration of LBBB was classical, including an electrophysiological study, the usual coronary angiography, and MSCT. All the morphological explorations of the coronary tree were normal., Discussion: In addition to complex electrophysiological mechanisms, coronary artery disease (CAD) is suspected, but remains infrequent in some EKG findings such as acquired LBBB, especially for patients with low cardiovascular risk factors as demonstrated with our aircrew members. However, in aerospace medicine the expert needs to prove the absence of CAD. The use of standard examinations (exercise stress test, stress myocardial scintigraphy, etc.) is controversial because of artifacts and a conventional coronary angiography is necessary. According to previous studies, including using a validated technique in our department (with 16-slice computed tomography), the excellent negative predictive value of MSCT (97 to 99%) may be a way to avoid invasive exploration during the investigation of a newly acquired LBBB in aviators with low cardiovascular risk.

The electrocardiographic appearances and the significance of right bundle branch block were described at the beginning of the 20th century. Typical appearances include prolongation > 0.12 s of the QRS complex, RR' or rR' or Rr' appearances in V1 and widened S waves in the leads exploring the left ventricle (SI, aVL, V5 and V6). A delay in the appearance of the intrinsic deflection > 0.08 s may also be observed in the right precordial leads and negative T waves with ST depression may be seen in V1 and sometimes in V2. Left axis deviation of the QRS complex greater than - 45 degrees suggests associated left anterior hemiblock. Right axis deviation beyond + 120 degrees is equivocal. The principal differential ECG diagnosis is the Brugada syndrome, a familial arrhythmogenic autosomal dominant cardiomyopathy of variable penetration. This diagnosis is suggested when ECG abnormalities are observed in patients with a personal or family history of sudden death. Right bundle branch block only seems to have haemodynamic consequences in cardiac failure with associated asynchrony of the left ventricle or in certain cases of right ventricular dilatation encountered in congenital heart disease. The prognosis of right bundle branch block in the absence of underlying cardiac disease is good but it may be poor in other cases, particularly coronary artery disease. Moreover, the prognosis of right bundle branch block to complete atrioventricular block is rare in the absence of associated cardiac disease.

Unlabelled: Multislice computed tomography (MSCT) is a non-invasive and validated technique to detect coronary stenoses. Some questions remain about its accuracy to detect coronary stenoses (CS), especially for asymptomatic patients (P) when a prior stress test isn't conclusive., Methods: MSCT was performed among 45 asymptomatic men (mean age: 58,3 +/- 16), with a high ten year risk of fatal cardiovascular disease (SCORE 2003 data for low-risk regions of Europe), without any previous coronary history and with previous non conclusive exercise testing. When significant (> 50%) CS was suspected at MSCT, an angiocoronarography (AC) was done., Results: Eighteen MSCT were normal, unsignificant CS (< 50%) were detected on 14 MSCT and significant coronary stenoses (SCS) for 13 P. Among this 13 P, 19 SCS were identified: 2 SCS of left main coronary artery (CA), 9 of the left descending CA, 6 of the right CA and 2 of the left circumflex CA. 13 CS were confirmed at AC. Finally, because of critical angiographic lesions +/- ischemia at nuclear tomoscintigraphy (NT), 9 P had coronary revascularization (7 catheter based, 2 surgical bypass), 4 P had medical treatment., Discussion: Benefits of this preliminary study are obvious: 9 coronary revascularization/45 P. However, the place of MSCT for the screening of CS is uncertain, but may be usefull as a complement for the screening of coronary arterial disease.

Aerobatics is an aerial sport which has many physiological constraints, principally cardiovascular, with a risk if not adapted of sudden mid-air incapacity which could jeopardise aviation safety, and thus justifies the selection and surveillance of pilots. The aeronautical constraints during flight are multiple, related to the environment traversed, how the aircraft functions and its movements. Those which cause accelerations (+G in particular) pose the problem of haemodynamic tolerance because they can induce loss of consciousness due to cerebral hypoxia. Tolerance of acceleration varies among individuals; it can be improved with training, certain protective manoeuvres, and is reduced by hypoxia, certain medications, dehydration and heat. Moreover, in aerobatics certain tricks require manoeuvres which reduce this tolerance to +G accelerations. This is the "push-pull" effect (&#95;G acceleration immediately followed by +G acceleration). This leads to a risk of sudden loss of consciousness with a load factor much lower than that which the pilot knows he is capable of tolerating. Besides the haemodynamic effects, the existence of an actual acceleration cardiomyopathy has been suggested but has not been proven in man. Finally, while changes in cardiac rhythm during accelerations are usual and relate to changes in vaso-sympathetic balance, ventricular and supra-ventricular rhythm disturbances are rare and are related to the intensity and duration of the acceleration.

The chloroquine is the mainly and most frequently drug used as antimalaric in the world, in spite of the extension of resistance phenomena. Besides, the chloroquine is also commonly indicated in rheumatology and dermatology as a chronic treatment of some connective tissue disease. The chloroquine has three main cardiovascular effect: membrane stabilizer, direct negative inotropic effect and direct arterial vasodilator. Thus, these cardiovascular iatrogenic effects of the chloroquine are important both through their potential frequency and seriousness. Personal clinical cases and medical review enables to identify the main effects, observed either with prophylactic, or curative, or even toxic dosages. The more often, there are some rhythm and conductance disorders, myocardiopathy, even sometimes vasoplegic shocks. A list of the commercial patent medicine including chloroquine enables to be aware, to prevent and to take into account the cardiovascular risks of a treatment newly set or carried on for long years.

The SiH2D2 asymmetric top has nine vibrational modes, five of them forming a pentad strongly perturbed by Coriolis interactions. High-level ab initio calculations of SiH2D2 have been performed which yield numerous spectroscopic parameters related to the harmonic and anharmonic force fields. The bending pentad comprising nu4(A1), nu7(B1), nu5(A2), nu9(B2), and nu3(A1) has been studied by high-resolution Fourier transform spectroscopy; the region 600-1050 cm-1 has been investigated with a resolution of ca. 4 x 10(-3) cm-1. Raman BOXCARS spectroscopy has been used for the infrared inactive nu5 band. The Raman apparatus function was 0.0054 cm-1. Assignments of about 4000 transitions including all bands have been made, mostly employing ground state combination differences techniques, and a global fit has been performed. The fundamentals nu4 (681.624 cm-1), nu7 (742.640 cm-1), nu5 (842.381 cm-1), nu9 (859.750 cm-1), and nu3 (942.741 cm-1) are strongly coupled by A-, B-, and C-type Coriolis interactions, and ab initio predictions of these interaction parameters were used to set up a network of interactions that was refined by the experimental data. The global standard deviation for the entire body of data is 7.1 x 10(-4) cm-1. Satisfactory synthetic spectra which are very sensitive to relative signs of dipole moment derivatives and Coriolis interaction constants were obtained with the guidance of ab initio calculations. Finally, fair to good agreement of experimental and ab initio calculated molecular parameters was obtained. For the first time, a complete analysis of the pentad of SiH2D2 in the 10-16 µm region has been carried out. A full set of rovibrational parameters is given for these five interacting levels, including first and second order Coriolis interaction constants. Copyright 1998 Academic Press.