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Aerosol lidar sensing of the middle atmosphere (30-65 km) was carried out in Obninsk over a year. The sensing at two wavelengths of 355 and 532 nm enabled the separation of Rayleigh and aerosol scattering contributions in lidar signals. Increased aerosol content is found within the 60-65 km altitude range. Monthly average lidar sensing data are compared with measurements of the radio meteor echo in Obninsk and Kollm (Germany). The correspondence between the time variations in the data of two types is revealed, which indicates the meteor origin of the aerosol. Possible physical causes of the appearance of the aerosol layer observed are discussed. [ABSTRACT FROM AUTHOR]

We briefly overview the periodic atmospheric motions in the period range from 1 h to a few dozen days. It is shown that many oscillations recorded by vertical seismometers, gravimeters, strainmeters, and tilt-meters reflect these motions, namely, the harmonics of the thermal atmospheric tide, free waves in the atmosphere, and Madden-Julian oscillation in the atmosphere-ocean system. The state of the art in studying the effects of these motions on seismic activity is described. On the basis of yearlong measurements by a three-channel Streckeisen STS2 seismometer at Collm (51.3° N, 13.0° E), susceptibility of the horizontal movements of the seismometer's pendulum to the periodic atmospheric motions with periods exceeding 2 days is explored for the first time. The wavelet and Fourier spectra of the signals recorded by both horizontal channels and the vertical channel of the seismometer demonstrate common features which coincide with the spectral traits of the simultaneous variations in the surface air pressure. These features are associated with the atmospheric planetary-scale Rossby waves and Madden-Julian oscillation. [ABSTRACT FROM AUTHOR]

Background: The pneumoperitoneum is the crucial element in laparoscopic surgery. Different clinical problems are associated with this procedure, which has led to various modifications of the technique. The aim of this guideline is to define the scientifically proven standards of the pneumoperitoneum. Methods: Based on systematic literature searches (Medline, Embase, and Cochrane), an expert panel consensually formulated clinical recommendations, which were graded according to the strength of available literature evidence. Recommendations: Preoperatively, all patients should be assessed for the presence of cardiac, pulmonary, hepatic, renal, or vascular comorbidity. Presupposing appropriate perioperative measures and surgical technique, there is no reason to contraindicate pneumoperitoneum in patients with peritonitis or intraabdominal malignancy. During laparoscopy, monitoring of end tidal CO2 concentration is mandatory. The available data on closed- (Veress needle) and open-access techniques do not allow us to principally favor the use of either technique. Using 2 to 5-mm instead of 5 to 10-mm trocars improves cosmetic result and postoperative pain marginally. It is recommended to use the lowest intraabdominal pressure allowing adequate exposure of the operative field, rather than using a routine pressure. In patients with limited cardiac, pulmonary, or renal function, abdominal wall lifting combined with low-pressure pneumoperitoneum might be an alternative. Abdominal wall lifting devices have no clinically relevant advantages compared to low-pressure (5–7 mmHg) pneumoperitoneum. In patients with cardiopulmonary diseases, intra- and postoperative arterial blood gas monitoring is recommended. The clinical benefits of warmed, humidified insufflation gas are minor and contradictory. Intraoperative sequential intermittent pneumatic compression of the lower extremities is recommended for all prolonged laparoscopic procedures. For the prevention of postoperative pain a wide range of treatment options exists. Although all these options seem to reduce pain, the data currently do not justify a general recommendation. [ABSTRACT FROM AUTHOR]

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Focuses on a study which investigated the correlation between mesopause region winds and the north Atlantic oscillation. Connection between upper atmospheric dynamics and tropospheric parameters; Discussion on the mesopause region wind field and European winter tropospheric parameters; Conclusions.

In the past, experimental investigations as well as theoretical considerations have shown that within fronts and inversions wind shear and vertical temperature gradient adjust in such a way that the Richardson number is at its critical value. Results from aircraft measurements now suggest that the shear within moving cold fronts, warm fronts and inversions shows different behaviour because of the different mechanisms controlling the Richardson numbers. This leads to higher Richardson numbers, and therefore to lower amounts of wind shear within moving cold fronts when compared to warm fronts and inversions. [ABSTRACT FROM AUTHOR]