Time Dependence of the Electron and Positron Components of the Cosmic Radiation Measured by the PAMELA Experiment between July 2006 and December 2015.

Cosmic-ray electrons and positrons are a unique probe of the propagation of cosmic rays as well as of the nature and distribution of particle sources in our Galaxy. Recent measurements of these particles are challenging our basic understanding of the mechanisms of production, acceleration, and propagation of cosmic rays. Particularly striking are the differences between the low energy results collected by the space-borne PAMELA and AMS-02 experiments and older measurements pointing to sign-charge dependence of the solar modulation of cosmic-ray spectra. The PAMELA experiment has been measuring the time variation of the positron and electron intensity at Earth from July 2006 to December 2015 covering the period for the minimum of solar cycle 23 (2006-2009) until the middle of the maximum of solar cycle 24, through the polarity reversal of the heliospheric magnetic field which took place between 2013 and 2014. The positron to electron ratio measured in this time period clearly shows a sign-charge dependence of the solar modulation introduced by particle drifts. These results provide the first clear and continuous observation of how drift effects on solar modulation have unfolded with time from solar minimum to solar maximum and their dependence on the particle rigidity and the cyclic polarity of the solar magnetic field.

An anomalous positron abundance in cosmic rays with energies 1.5-100 GeV.

Antiparticles account for a small fraction of cosmic rays and are known to be produced in interactions between cosmic-ray nuclei and atoms in the interstellar medium, which is referred to as a 'secondary source'. Positrons might also originate in objects such as pulsars and microquasars or through dark matter annihilation, which would be 'primary sources'. Previous statistically limited measurements of the ratio of positron and electron fluxes have been interpreted as evidence for a primary source for the positrons, as has an increase in the total electron+positron flux at energies between 300 and 600 GeV (ref. 8). Here we report a measurement of the positron fraction in the energy range 1.5-100 GeV. We find that the positron fraction increases sharply over much of that range, in a way that appears to be completely inconsistent with secondary sources. We therefore conclude that a primary source, be it an astrophysical object or dark matter annihilation, is necessary.

New measurement of the antiproton-to-proton flux ratio up to 100 GeV in the cosmic radiation.

A new measurement of the cosmic-ray antiproton-to-proton flux ratio between 1 and 100 GeV is presented. The results were obtained with the PAMELA experiment, which was launched into low-Earth orbit on-board the Resurs-DK1 satellite on June 15th 2006. During 500 days of data collection a total of about 1000 antiprotons have been identified, including 100 above an energy of 20 GeV. The high-energy results are a tenfold improvement in statistics with respect to all previously published data. The data follow the trend expected from secondary production calculations and significantly constrain contributions from exotic sources, e.g., dark matter particle annihilations.

[Adequate gas exchange in two-sided and combined surgeries on thoracic and abdominal organs].

Method of combined artificial lung ventilation during simultaneous two-sided operations on the lungs was studied in 60 patients. This method is based on traditional ALV with parameters calculated according to functional state of the patient's respiratory system, and additional high-frequency jet pulmonary ventilation. The developed method was not accompanied by any severe disorders of gas exchange and mechanics of ventilation.

[Surgical approach in bilateral and combined echinococcosis of the lung].

One hundred and two patients aged from 4 to 65 years with echinococcosis were treated. Solitary cysts in both lungs were diagnosed in 69 patients, multiple cysts -- in 33 patients. In 10 cases small and middle cysts were in the upper parts of both lungs. These patients underwent one-stage operation consisting in lateral thoracotomy, removing of the cyst from one lung, incision of retrosternal mediastinal pleura, removing of the cyst from the second lung, drainage of pleural cavity. Fifteen patients with combined echinococcosis of the upper lobe of the right lung and liver were operated with another one-stage surgical method through thoracotomy in the third and sixth or seventh intercostal space. These methods are characterized by low traumaticity, decreased number of postoperative complications and hospital stay.

[Experience in the surgical treatment of chronic suppurative lung disease in children]. / Opyt khirurgicheskogo lecheniia khronicheskikh nagnoitel'nykh zabolevanii legkikh u detei.

UNLABELLED: Operations were performed on 750 children with cystic hypoplasia and dysontogenetic and acquired bronchiectases. The operation volume: pulmonectomy, lobectomy, combined resections, resection of pulmonary tissue with extirpation of bronchi, extirpation of bronchi. COMPLICATIONS: atelectasis, pneumonia, intrapleural hemorrhage were encountered in 87 (11.6%) children. Six (0.8%) children died. Recurrent or residual bronchiectases were found in 27 children, 18 underwent a second operation. Recurrences were encountered mainly in children with dysontogenetic bronchiectases.