Experimental demonstration of energy-chirp control in relativistic electron bunches using a corrugated pipe.

The first experimental study is presented of a corrugated wall device that uses wakefields to remove a linear energy correlation in a relativistic electron beam (a "dechirper"). Time-resolved measurements of both longitudinal and transverse wakefields of the device are presented and compared with simulations. This study demonstrates the feasibility to employ a dechirper for precise control of the beam phase space in the next generation of free-electron-lasers.

Evidence of high harmonics from echo-enabled harmonic generation for seeding x-ray free electron lasers.

Echo-enabled harmonic generation free electron lasers hold great promise for the generation of fully coherent radiation in x-ray wavelengths. Here we report the first evidence of high harmonics from the echo-enabled harmonic generation technique in the realistic scenario where the laser energy modulation is comparable to the beam slice energy spread. In this experiment, coherent radiation at the seventh harmonic of the second seed laser is generated when the energy modulation amplitude is about 2-3 times the slice energy spread. The experiment confirms the underlying physics of echo-enabled harmonic generation and may have a strong impact on emerging seeded x-ray free electron lasers that are capable of generating laserlike x rays which will advance many areas of science.

Demonstration of the echo-enabled harmonic generation technique for short-wavelength seeded free electron lasers.

We report the first experimental demonstration of the echo-enabled harmonic generation technique, which holds great promise for generation of high-power, fully coherent short-wavelength radiation. In this experiment, coherent radiation at the 3rd and 4th harmonics of the second seed laser is generated from the so-called beam echo effect. The experiment confirms the physics behind this technique and paves the way for applying the echo-enabled harmonic generation technique for seeded x-ray free electron lasers.

[Effectiveness of the management of spinal problems with UMLP-07].

The UMLP-07 system for multifactorial treatment of the spinal column allows for the performance of various therapeutic procedures including relaxation of muscular-ligamentous structures by correction of their anatomical configuration due to flowability of the large mass of glass balls. The balls radioactively heated to the work temperature exhibit high thermal capacity and deeply warm up spinal structures thereby activating metabolic repair processes. Hinge elements of head and leg supports allow for controlled traction of the spine by elimination of functional blocks. Moreover, the balls produce acupuncture-like effect on biologically active points at the back of the body. Courses of therapy for the treatment of degenerative and dystrophic changes in the spine based on the use of UMLP-07 help to alleviate pain, correct asymmetry of right and left leg loading, improve dorsolumbar muscle hypertone, increase mobility of the spinal column.

Using the beam-echo effect for generation of short-wavelength radiation.

We propose to use the mechanism of an echo effect previously observed in hadron accelerators for up-frequency conversion of density modulation in an electron beam. We show that, for generation of high harmonics, this method is much more efficient in comparison with the currently used approach. A one-dimensional model of the effect is developed which allows us to optimize the amplitude of the modulation for a given harmonic number.

Future possibilities of the Linac Coherent Light Source.

A study of the potential for the development of the Linac Coherent Light Source (LCLS) beyond the specifications of the baseline design is presented. These future developments include delivery of X-ray pulses in the 1 fs regime, extension of the spectral range, increase of the FEL power, exploitation of the spontaneous emission, and a more flexible time structure. As this potential is exploited, the LCLS can maintain its role as a world-leading instrument for many years beyond its commissioning in 2008 and initial operation as the world's first X-ray free-electron laser.

Femtosecond and subfemtosecond x-ray pulses from a self-amplified spontaneous-emission-based free-electron laser.

We propose a novel method to generate femtosecond and subfemtosecond photon pulses in a free-electron laser by selectively spoiling the transverse emittance of the electron beam. Its merits are simplicity and ease of implementation. When the system is applied to the Linac Coherent Light Source, it can provide x-ray pulses the order of 1 fs in duration containing about 10(10) transversely coherent photons.

Ponderomotive laser acceleration and focusing in vacuum for generation of attosecond electron bunches.

A novel approach for the generation of ultrabright attosecond electron bunches is proposed, based on acceleration in vacuum, by a short laser pulse. The laser-pulse profile is tailored such that the electrons are both focused and accelerated by the ponderomotive force of the light. Using time-averaged equations of motion, analytical criteria for optimal regime of acceleration are found. It is shown that for realistic laser parameters, a beam with up to 10(6) particles and normalized transverse and longitudinal emittances <10(-8) m can be produced.

[The development of the syndrome of congestive parenchymatous organs under conditions of short-term hypokinesia]. / Razvitie sindroma zastoinykh parenkhimatoznykh organov v usloviiakh kratkovremennoi gipokinezii.

Five series of head-down (-10 degrees to -30 degrees, up to 18 hr) tilt tests were performed with participation of 65 healthy male subjects. The ultrasonic technique was used to investigate the liver, spleen, pancreas, kidney, and the main abdominal vessels, i.e. aorta in the abdomen and superior mesenteric artery, interior caval, portal, and splenic veins. A few hours of HDT already brought about a complex of load-deprivation reflexes (the syndrome of stagnant parenchymal organs) characterized by a prolonged venous congestion in the abdominal organs-vessels system, increases in sizes and blood filling of the liver, spleen, pancreas, kidney, and the main arteries and veins in this hemodynamic region. This was the first time when increases in pancreas including its head, body and tail, and the abdominal blood vessels were quantified at the beginning of adaptation to HDT. The load-deprivation reflexes arising in this period were hemodynamic by nature. Considering the significant functional strain of the abdominal organs and vessels and particularly the limited control of excessive blood flow towards the pancreas and kidneys, there is a good reason to look into the ways to improve the existing countermeasures against the consequences of immobilization for humans both in general clinic and preventive medicine, and in short- and long-term space missions.

[From present day aviation medicine to aviation anthropologic ecology of the future]. / Ot aviatsionnoi meditsiny nastoiashchego k aviatsionnoi antropoekologii budushchego.

Rationale is given to the proposition that aviation medicine including psychophysiology and ergonomics is a peculiar kind of aviation anthropoecology as a variety of the present-day integrative science of human. This is grounded, firstly, on analysis of any scientific finding of aviation medicine in the light of two principles of the contemporary occupational medicine, i.e. human health and reasonable risk (which is an equivalent of safety) and, secondly, systemic study from this angle of all, from molecular to social, levels of the biological integration man of flying.

Influence of bisphosphonates on calcium metabolism and bone tissue during simulation of the physiological effects of microgravity.

At present a significant experience has been gathered in experimental and clinical use of synthetic derivatives of bisphosphonic acid. Purpose of our study was to investigate the effects of bisphosphonates on calcium metabolism and bone tissue in humans and animals under the conditions simulating the physiological effects of microgravity. In a series of experiments with animals the effectiveness of various preparations and treatment plans was compared Action of 1-hydroxyethyliden-1, 1-bisphosphonic acid (EHBP, xydiphon) on calcium metabolism and bone tissue in human was the subject of experiments with long-term head-down tilt (HDT).

[Advancement and goals of the aviation human engineering]. / Dostizheniia i zadachi aviatsionnoi ergonomiki.

Analyzed were the efforts of the State Scientific-Research Test Institute of Aviation and Space Medicine to weigh and account the human factor in designing and upgrading avionics and aviation machinery. Described are the policy of human engineering support to the development, evaluation, and operation of aviation machinery, and the benefits from the human factor knowledge to the specifications for aviation machinery and allowance for the psychophysiological aptitudes of human on different phases of development of ergatic aviation systems. Outlined is the mainstream of ergonomic enhancement of the quality and safety, and humanization of the activities of different aviation specialists.