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Background: Although growth differentiation factor 15 (GDF15) is known to increase with disease and is associated with low physical performance, the role of GDF15 in normal ageing is still not fully understood. Specifically, the influence of circulating GDF15 on impairments in maximal muscle power (a major contributor to functional limitations) and the underlying components has not been investigated. Methods: Data from 1305 healthy women and men aged 20 to 93 years from The Copenhagen Sarcopenia Study were analysed. Circulating levels of GDF15 and markers of inflammation (tumor necrosis factor-alpha, interleukin-6, and high-sensitivity C-reactive protein) were measured by ELISA (R&D Systems) and multiplex bead-based immunoassays (Bio-Rad). Relative (normalized to body mass), allometric (normalized to height squared), and specific (normalized to leg muscle mass) muscle power were assessed by the Nottingham power rig [leg extension power (LEP)] and the 30 s sit-to-stand (STS) muscle power test. Total body fat, visceral fat, and leg lean mass were assessed by dual energy X-ray absorptiometry. Leg skeletal muscle index was measured as leg lean mass normalized to body height squared. Results: Systemic levels of GDF15 increased progressively as a function of age in women (1.1 ± 0.4 pg·mL−1·year−1) and men (3.3 ± 0.6 pg·mL−1·year−1) (both P < 0.05). Notably, GDF15 increased at a faster rate from the age of 65 years in women (11.5 ± 1.2 pg·mL−1·year−1, P < 0.05) and 70 years in men (19.3 ± 2.3 pg·mL−1·year−1, P < 0.05), resulting in higher GDF15 levels in men compared with women above the age of 65 years (P < 0.05). Independently of age and circulatory markers of inflammation, GDF15 was negatively correlated to relative STS power (P < 0.05) but not LEP, in both women and men. These findings were mainly explained by negative associations of GDF15 with specific STS po

The essay addresses various forms of dialogue with F. M. Dostoevsky in the cycle of stories by Yuri Buida ‘The Osor’ins Chronicles’. The authors show that this dialogue is manifested through intertextual connections, allusions, details, narrative techniques defining the inner subplot of the cycle associated with the types of characters, philosophical problems inherent in Dostoevsky’s works (freedom and lack of freedom, crime and punishment, passion and lust), and also with the prophetic forebodings of the writer., El ensayo aborda diversas formas de diálogo con F. M. Dostoievski en el ciclo de historias de Yuri Buida "The Osor’ins Chronicles". Los autores muestran que este diálogo se manifiesta a través de conexiones intertextuales, alusiones, detalles, técnicas narrativas que definen la trama interna del ciclo asociado con los tipos de personajes, problemas filosóficos inherentes a las obras de Dostoievski (libertad y falta de libertad, crimen y castigo, pasión y lujuria), y también con los presentimientos proféticos del escritor.

Aim: Previous reports suggest that low-load muscle exercise performed under blood flow restriction (BFR) may lead to endurance adaptations. However, only few and conflicting results exist on the magnitude and timing of microvascular adaptations, overall indicating a lack of angiogenesis with BFR training. The present study, therefore, aimed to examine the effect of short-term high-frequency BFR training on human skeletal muscle vascularization. Methods: Participants completed 3 weeks of high-frequency (one to two daily sessions) training consisting of either BFR exercise [(BFRE) n = 10, 22.8 ± 2.3 years; 20% one-repetition maximum (1RM), 100 mmHg] performed to concentric failure or work-matched free-flow exercise [(CON) n = 8, 21.9 ± 3.0 years; 20% 1RM]. Muscle biopsies [vastus lateralis (VL)] were obtained at baseline, 8 days into the intervention, and 3 and 10 days after cessation of the intervention to examine capillary and perivascular adaptations, as well as angiogenesis-related protein signaling and gene expression. Results: Capillary per myofiber and capillary area (CA) increased 21-24 and 25-34%, respectively, in response to BFRE (P < 0.05-0.01), while capillary density (CD) remained unchanged. Overall, these adaptations led to a consistent elevation (15-16%) in the capillary-to-muscle area ratio following BFRE (P < 0.05-0.01). In addition, evaluation of perivascular properties indicated thickening of the perivascular basal membrane following BFRE. No or only minor changes were observed in CON. Conclusion: This study is the first to show that short-term high-frequency, low-load BFRE can lead to microvascular adaptations (i.e., capillary neoformation and changes in morphology), which may contribute to the endurance effects previously documented with BFR training. The observation of perivascular membrane thickening suggests that high-frequency BFRE may be associated with significant vascular stress.

Band structure calculations relevant to bis-ethylenedithio-tetrathiafulvalene-based charge transfer salts containing tris(oxalato)metallate anions, with generic formula (BEDT-TTF)4A[M(C2O4)3]·Solv, where A is a monovalent anion, M is a trivalent cation and Solv is a solvent, suggest that their Fermi surface is liable to achieve networks of compensated orbits coupled by magnetic breakdown. Even though this picture accounts for quantum oscillations spectra of a number of these compounds, puzzling results can be noticed in several cases, pointing to the possibility of Fermi surface reconstruction at low temperature.