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Background Early repolarization in the anterior ECG leads (ERV2–4) is considered to be a sign of right ventricular (RV) remodeling, but its etiology and importance are unclear. Methods A total of 243 top-level endurance-trained athletes (ETA; 183 men and 60 women, weekly training hours: 15–20) and 120 leisure-time athletes (LTA; 71 men and 49 women, weekly training hours: 5–6) were investigated. The ERV2–4 sign was evaluated concerning type of sport, gender, transthoracic echocardiographic parameters, and ECG changes, which can indicate elevated RV systolic pressure [left atrium enlargement (LAE), right atrium enlargement (RAE), RV conduction defect (RVcd)]. Results Stroke volume and left ventricular mass were higher in ETAs vs. LTAs in both genders (p 2–4 sign was significantly higher in men than in women [p = 0.000, odds ratio (OR) = 36.4] and in ETAs than in LTAs (p = 0.000). The highest ERV2–4 prevalence appeared in the most highly trained triathlonists and canoe and kayak paddlers (OR = 13.8 and 5.2, respectively). Within the ETA group, the post-exercise LAE, RAE, and RVcd changes developed more frequently in cases with than without ERV2–4 (LAE: men: p p p p 2–4 sign (OR = 4.0, 3.7, and 3.8, respectively). Conclusions According to these results, ERV2–4 develops mainly in male ETAs due to long-lasting and repeated endurance training. The ERV2–4 sign indicates RV’s adaptation to maintain higher compensatory pulmonary pressure and flow during exercise but its danger regarding malignant arrhythmias is unclear.

Progressive supranuclear palsy (PSP) is a degenerative movement disorder involving gradual deterioration and death of specific brain areas. Extrapyramidal features (losing balance, frequent falls, and paralysis of vertical gaze) make daily life difficult for the individual. Novel rehabilitation techniques complementary to human or robotic rehabilitation methods in such cases are emerging. Repetitive transcranial magnetic stimulation (rTMS) is such a tool, which began to be used in the rehabilitation of motor disorders. We observed positive effects of rTMS (over the motor cortex area, 1.0 sec–1, 20 min per day, for 5 days) on the motor functions in a PSP case using a mechanography approach (pre- and post-treatment goniometry and dynamometry). The respective measurements showed that rTMS led to noticeable increases in the angles of most tested movements of the upper and lower limbs of the patient and in the forces developed during such movements.

High power laser science and engineering 8, e24 (2020). doi:10.1017/hpl.2020.23, Published by Cambridge Univ. Press, Cambridge

The Petawatt Field Synthesizer (PFS) under construction at the Max-Planck Institute for Quantum Optics is an optical parametric chirped pulse amplification (OPCPA) system designed to generate few-cycle pulses with petawatt-scale peak power [1, 2]. Such pulses are of high interest for laser-matter interaction experiments, for example for the generation of isolated attosecond pulses with unprecedented efficiency [3]. Here we report on the current performance and upgrade plans of the OPCPA chain of PFS.

Lymph node (LN) infiltration by neoplastic process involves important changes in lymph node immune microenvironment. In particular, regulatory T cells (Treg) seem to have a key role in altering the immunoediting function of the immune system which leads to the elusion of the tumor from immune surveillance. In this study, we evaluate the expression of T-cell markers in CD4+ and CD8+ subsets from tumor-positive and tumor-negative lymph nodes from the same, advanced stage breast cancer patient. The study was carried out on 3 patients and similar results were obtained. Flow cytometric analysis of CD8+ cells demonstrated a significant difference in the expression of CD25, CD45RA, CD45RO, and GITRL (Glucocorticoid-Induced TNF receptor-Related ligand). Flowcytometric analysis of CD4+ cells demonstrated a significant difference in the expression of GITR (Glucocorticoid-Induced TNF receptor-Related), CD25, FoxP3 (Forkhead box P3), CD28, and CD45RA. Multiple staining allowed the identification of two Treg subpopulations, CD4+CD25highGITR+CD127−/low and CD4+CD25lowGITR+CD127+ cells, proving that both are increased in the positive nodes in comparison with the negative nodes from the same patient. We identified for the first time the CD4+CD25lowGITR+CD127+ Treg subpopulation in cancer, and the 2.6 fold increase in positive LN suggests that this Treg subpopulation could be a key player in metastasis. We also found GITRL expression in the CD8 lymphocytes, which may also contribute to the changes of metastatic lymph node microenvironment. These findings make both GITR and GITRL good possible co-candidates for future therapeutical intervention against metastasis and perhaps also as disease evolution biomarkers.

UNLABELLED To clarify whether the higher E/A quotient of male athletes is a favourable change in the intrinsic relaxation properties of the left ventricle. METHODS Peak early (E) and atrial blood flow velocities (A) were assessed by Doppler echocardiography at rest in 1237 males (939 athletes) in Hungary. Data were collected between 1993 – 2009. Relationship between E/A and resting heart rate (HR), was determined by linear regression analysis. RESULTS The E/A decreased with age, the rate of decrease was slower in the physically trained subjects, except in children. In children, adolescent-young and young adult subjects E/A against HR equations of the athletic and nonathletic groups were similar, differences between the means were only due to the differences of the HR. In the 31 – 44 yr old males, the intercepts of the athletes' regression lines were higher. The oldest (>44 yr) active subjects showed a significant regression while sedentary males did not. CONCLUSIONS The HR-independent beneficial effect of regular physical training on the diastolic function manifests itself at the older ages. The impact of resting HR should always be taken into consideration when assessing intergroup differences in the E/A ratio, especially when studying the effect of exercise training upon cardiac function.

Sudden cardiac death (SCD) of athletes usually occurs during warm-up or shortly after training. At this point sympathetic tone is still elevated but oxygen demand does not differ from resting levels. It is supposed not to have a primarily ischemic origin but most likely relates to repolarization abnormalities which can be associated with intracellular cAMP level caused by increased sympathetic tone. The mediators of sympathetic nervous system are the catecholamines (epinephrin, norepinephrin). Measuring QT-dispersion can show the repolarization's inhomogeneity. 27 elite soccer players, 28 triathletes and 29 non-trained control person took part in our study. It was recorded cardiac ultrasound, an ECG and taken blood before and after exercise. We found significantly higher QT-dispersion and catecholamines in soccer players compared to the triathletes and the controls. However the soccer players did not show larger athlete's heart than the triathletes. After exercise the increased repolarization inhomogeneity persisted in soccer players, but in triathletes it decreased. Increased sympathetic tone in athletes can enhance arrhythmia propensity. Our data may explain why the soccer players die of sudden cardiac death most commonly in Europe.

Importance of the athlete's heart has been arisen in the last decades.ulConsequences of the sedentary way of life are the most threatening through the impairments of the cardiovascular system. Endurance performance is mostly limited by the characteristics of the athlete's heart. Sudden death of the athletes is always associated with cardiac disorders./ulMain characteristics of the athlete's heart can be divided into morphologic, functional and regulatory ones.ulThe main morphologic characteristics are the physiologic left ventricular (LV) hypertrophy and a richer coronary capillary network. The functional adaptation contains a better systolic and diastolic function, modified metabolism and electric characteristics. The most easily detected modification is the better LV diastolic function. Adaptation of the cardiac regulation is manifested mostly by a lower heart rate (HR)./ulSummarizing: the athlete's heart is an enlarged but otherwise normal heart characterized by a low heart rate, an increased pumping capacity, and a greater ability to deliver oxygen to skeletal muscle.

Characteristics of the athlete's heart have been investigated mostly in the left ventricle (LV); reports referring to the right ventricle (RV) have only appeared recently. The aim of the present study was to compare the training effects on RV and LV in elite male endurance athletes. To this end, echocardiography was conducted in 52 elite endurance athletes (A) and in 25 non-athletes (NA). Differences between A and NA in the morphology was more marked in the RV (body-size-matched (rel.)) long axis diastolic diameter (RVLADd): 63.4 ± 6.3 vs. 56.4 ± 6.3; rel. short axis diastolic diameter (RVSADd): 27.3 ± 3.6 vs. 23.6 ± 2.7 mm/m, RV diastolic area 28 ± 5.0 vs. 21.3 ± 4.3 cm2 in all cases, p < 0.001) than in the LV (rel. LVLADd: 63.8 mm/m ± 5.6 vs. 60.7 mm/m ± 6.6, p < 0.05, rel.LVSADd 37.8 ± 3.1 vs. 35.3 ± 2.4, no difference). In the athletes ratios of peak early to late diastolic filling velocity (2.07 ± 0.51 vs. 1.75 ± 0.36, p < 0.01), the TDI-determined E'/A' ratio in the septal (1.89 ± 0.55 vs. 1.62 ± 0.55, p < 0.05) and lateral (2.62 ± 0.72, vs. 2.18 ± 0.87, p < 0.001) walls were significantly higher than in NA only in the LV. Results indicate that in male endurance athletes morphologic adaptation is similar or slightly stronger in the RV than in the LV, functional adaptation seems to be stronger in the LV.

Yb:YAG thin-disk lasers offer extraordinary output power, but systems delivering femtosecond pulses at a repetition rate of hundreds of kilohertz are scarce, even though this regime is ideal for ultrafast electron diffraction, coincidence imaging, attosecond science, and terahertz (THz) spectroscopy. Here we describe a regenerative Yb:YAG amplifier based on thin-disk technology, producing 800-fs pulses at a repetition rate adjustable between 50 and 400 kHz. The key design elements are a short regenerative cavity and fast-switching Pockels cell. The average output power is 130 W before the compressor and 100 W after compression, which at 300 kHz corresponds to pulse energies of 430 and 330 μJ, respectively. This is sufficient for a wide range of nonlinear conversions and broadening/compression schemes. As a first application, we use optical rectification in LiNbO₃ to produce 30-nJ single-cycle THz pulses with 6 W pump power. The electric field exceeds 10 kV/cm at a central frequency of 0.3 THz, suitable for driving structural dynamics or controlling electron beams.

In our previous review characteristics of the athlete’s heart were divided into three groups: morphologic (left ventricular (LV) hypertrophy, improved coronary circulation), functional (better diastolic function) and regulatory (lower heart rate (HR)) features. In the present review, the influences of the types of sports and the age on the athlete’s heart are discussed. Studies using echocardiographic, Doppler-echocardiographic, tissue Doppler imaging (TDI) and magnetic resonance imaging (MRI) results are mostly involved. The coronary circulation was investigated overwhelmingly in animal experiments. In the LV hypertrophy a major contributor is the increase of the LV wall thickness (WT) than that of the LV internal diameter (ID). A right ventricular (RV) hypertrophy can also be seen in athletes. Athletic features are induced mostly by endurance training. Approximately two years regular physical training is needed to develop characteristics of the athlete’s heart, hence, in the young children they are less marked. LV hypertrophy and lower HR are characteristic in young and adult athletes, but they are less marked in older ones. A richer coronary capillary network can develop mostly at a young age.

A simple and easy to implement technique for femtosecond pulse characterization is proposed and experimentally verified. It is based on the introduction of a known amount of dispersion (by controlling the number of passes through dispersive material) and subsequent recording of the spectral positions of second harmonic peaks obtained in a non-linear crystal. Such dependence allows for direct retrieval of the pulse spectral phase. The presented pulse characterization method is beneficial especially for broadband pulses, where the second harmonic spectrum exceeds the detection bandwidth of a single spectrometer.

We report on a newly-developed low-loss broadband high-dispersion mirrors which are capable of taking over the role of prisms and gratings in mJ-scale femtosecond chirped-pulse amplifiers. The compression of a 1.4 mJ chirped pulse in a DMC down to sub-20-fs is demonstrated.

Extreme Light Infrastructure (ELI), the first research facility hosting an exawatt class laser will be built with a joint international effort and form an integrated infrastructure comprised at last three branches: Attosecond Science (in Szeged, Hungary) designed to make temporal investigation at the attosecond scale of electron dynamics in atoms, molecules, plasmas and solids. High Field Science will be mainly focused on producing ultra intense and ultra short sources of electons, protons and ions, coherent and high energetic X rays (in Prague, Czech Republic) as well as laserbased nuclear physics (in Magurele, Romania). The location of the fourth pillar devoted to Extreme Field Science, which will explore laser-matter interaction up to the non linear QED limit including the investigation of vacuum structure and pair creation, will be decided after 2012. The research activities will be based on an incremental development of the light sources starting from the current high intensity lasers (APOLLON, GEMINI, Vulcan and PFS) as prototypes to achieve unprecedented peak power performance, from tens of petawatt up to a fraction of exawatt (1018 W). This last step will depend on the laser technology development in the above three sites as well as in current high intensity laser facilities.

The Petawatt‐Field‐Synthesizer (PFS) project at the Max‐Planck‐Institut fur Quantenoptik (Garching), aims at combining few‐cycle pulse durations with petawatt‐scale peak powers by using short pulses (on the few‐ps scale) for both seeding and pumping an optical parametric chirped pulse amplification (OPCPA) chain. Such a short‐pulse pumped OPCPA approach imposes very strict demands on the synchronization between the seed and the pump pulses, i.e. the timing jitter between the pulses has to be below the 100 fs‐level. We report on recent progress on the development of the PFS system, in particular about the investigation of the pump‐seed timing jitter. We have identified the grating stretcher/compressor setup of the pump laser chain as the main source of a temporal instability of about >200 fs rms and propose ways to eliminate this in order to allow for first short‐pusle pumped OPCPA experiments.

Latest developments in the field of laser-wakefield accelerators (LWFAs) have led to relatively stable electron beams in terms of peak energy, charge, pointing and divergence from mmsized accelerators. Simulations and LWFA theory indicate that these beams have low transverse emittances and ultrashort bunch durations on the order of ∼ 10 fs. These features make LWFAs perfectly suitable for driving high-brightness X-ray undulator sources and free-electron lasers (FELs) on a university-laboratory scale.With the detection of soft-X-ray radiation from an undulator source driven by laser-wakefield accelerated electrons, we succeeded in achieving a first milestone on this path. The source delivers remarkably stable photon beams which is mainly due to the stable electron beam and our miniature magnetic quadrupole lenses, which significantly reduce its divergence and angular shot-to-shot variation. An increase in electron energy allows for compact, tunable, hard-Xray undulator sources. Improvements of the electron beams in terms of charge and energy spread will put table-top FELs within reach. © 2010 American Institute of Physids.

Quasi-monoenergetic, laser-driven electron beams of up to ∼ 200 MeV in energy have been generated from steady-state-flow gas cells [1], These beams are emitted within a low-divergence cone of 2.1 ± 0.5 mrad FWHM and feature unparalleled shot-to-shot stability in energy (2.5% rms), pointing direction (1.4 mrad rms) and charge (16% rms) owing to a highly reproducible plasma-density profile within the laser-plasma-interaction volume. Laser-wakefield acceleration (LWFA) in gas cells of this type constitutes a simple and reliable source of relativistic electrons with well defined properties, which should allow for applications such as the production of extreme-ultraviolet undulator radiation in the near future. © 2009 American Institute of Physics.

We report a novel implementation of chirped-pulse amplification (CPA) by dominantly using dispersive multilayer mirrors for chirp control. Our prototyp dispersive-mirror (DMC) compressor has been designed for a kHz Ti:sapphire amplifier and yielded--in a proof-of-concept study--millijoule-energy, sub-20-fs, 790-nm laser pulses with an overall throughput of approximately 90% and unprecedented spatio-temporal quality. Dispersive-mirror-based CPA permits a dramatic simplification of high-power lasers and affords promise for their advancement to shorter pulse durations, higher peak powers, and higher average powers with user-friendly systems.

This paper aims to numerically and experimentally study optical harmonic generation from solid fused silica targets. 1D particle-in-cell (PIC) simulation and pump-probe femtosecond technique are used to characterize the spectral, spatial, and temporal properties of the high-order harmonics. PIC code indicates that it is quite feasible that surface harmonics generated at laser intensities of 1020 W/cm2 can produce a train of or even single attosecond pulses in the 20-70 eV spectral range.

Chirped-pulse amplification (CPA) has become a common technique for damage-free amplification of the light pulses to TW-level or even higher. The standard CPA systems often use diffraction grating based stretchercompressor systems or bulk material as the stretcher and pairing double-prism as pulse compressors. Prism compressors are preferred over grating based systems, if the required stretching factor is small, because of their high throughput and smaller amount of higher-order dispersion. In case of a prism compressor, the amplified pulses enter positively chirped. The prism compressor introduces sufficient negative group-delay dispersion (GDD) due to the geometrical path, so that the pulses are slightly overcompressed (negatively chirped) before entering the last prism. The pulses then are finally compressed by the positive GDD of the bulk material while propagating through the last prism. Since the final compression takes place in bulk material, self-phase modulation (SPM) can occur even at modest pulse energies which in turn causes spectral narrowing in the compressed pulses (Fig. 1a) owing to the negative chirp of the pulses. Hybrid pulse compression (HPC) [1] was proposed to overcome this SPM in the prism material. Here, the pulses after the amplifier are overcompressed by increasing the prism separation. The pulses still maintain their negative chirp after the last prism and are finally compressed by the positive-dispersive mirrors (PDM). For high energy (and hence intensity) pulses, ever more negative chirp is required to avoid SPM. Therefore the required prism separation quickly becomes inconvenient and may even lead to spectral clipping in the second pair of prisms. Moreover, the increased prism separation also results in a change in the higher-order dispersion components, which in turn requires additional dispersion management.