Master athletes have higher miR-7, SIRT3 and SOD2 expression in skeletal muscle than age-matched sedentary controls.

Regular physical exercise has health benefits and can prevent some of the ageing-associated muscle deteriorations. However, the biochemical mechanisms underlying this exercise benefit, especially in human tissues, are not well known. To investigate, we assessed this using miRNA profiling, mRNA and protein levels of anti-oxidant and metabolic proteins in the vastus lateralis muscle of master athletes aged over 65 years and age-matched controls. Master athletes had lower levels of miR-7, while mRNA or protein levels of SIRT3, SIRT1, SOD2, and FOXO1 levels were significantly higher in the vastus lateralis muscle of master athletes compared to muscles of age-matched controls. These results suggest that regular exercise results in better cellular metabolism and antioxidant capacity via maintaining physiological state of mitochondria and efficient ATP production and decreasing ageing-related inflammation as indicated by the lower level of miR-7 in master athletes

Seasonal patterns and relationships among coccidian infestations, measures of oxidative physiology, and immune function in free-living house sparrows over an annual cycle

Temporal variation in oxidative physiology and its associated immune function may occur as a result of changes in parasite infection over the year. Evidence from field and laboratory studies suggests links between infection risk, oxidative stress, and the ability of animals to mount an immune response; however, the importance of parasites in mediating seasonal change in physiological makeup is still debated. Also, little is known about the temporal consistency of relationships among parasite infestation, markers of oxidative status and immune function in wild animals, and whether variation in oxidative measures can be viewed as a single integrated system. To address these questions, we sampled free-living house sparrows (Passer domesticus) every 2 mo over a complete year and measured infestation with coccidian parasites as well as nine traits that reflect condition, oxidative physiology, and immune function. We found significant seasonal variation in coccidian infestation and in seven out of nine condition and physiological variables over the year. However, we found little support for parasite-mediated change in condition, oxidative physiology, and immune functions in house sparrows. In accordance with this, we found no temporal consistency in relationships between the intensity of infestation and physiology. Among measures of oxidative physiology, antioxidants (measured as the total antioxidant capacity and the concentration of uric acid in the plasma) and oxidative damage (measured through the level of malondialdehyde in plasma) positively and consistently covaried over the year, while no such associations were found for the rest of traits (body mass, total glutathione, and leukocyte numbers). Our results show that natural levels of chronic coccidian infection have a limited effect on the seasonal change of physiological traits, suggesting that the variation of the latter is probably more affected by short-term disturbances, such as acute infection and/or season-specific stress stimuli

Certified reference materials for radionuclides in Bikini Atoll sediment (IAEA-410) and Pacific Ocean sediment (IAEA-412)

The preparation and characterization of certified reference materials (CRMs) for radionuclide content in sediments collected offshore of Bikini Atoll (IAEA-410) and in the open northwest Pacific Ocean (IAEA-412) are described and the results of the certification process are presented. The certified radionuclides include: 40K, 210Pb (210Po), 226Ra, 228Ra, 228Th, 232Th, 234U, 238U, 239Pu, 239+240Pu and 241Am for IAEA-410 and 40K, 137Cs, 210Pb (210Po), 226Ra, 228Ra, 228Th, 232Th, 235U, 238U, 239Pu, 240Pu and 239+240Pu for IAEA-412. The CRMs can be used for quality assurance and quality control purposes in the analysis of radionuclides in sediments, for development and validation of analytical methods and for staff training

Po accumulation by components of the Black Sea ecosystem

The naturally occurring radionuclide 210Po was determined in different components of the Black Sea ecosystem. The specific activity of 210Po in water in the open part of the sea was about 1Bq ⋅ m-3. The range of 210Po specific activity in bottom sediments was 4.5–500 Bq ⋅ kg-1 dry weight depending on their type, area and depth of collection. The highest values were found in the NW part of the Black Sea. Sediment distribution coefficients (Kd) of 210Po for bottom sediments, calculated on a dry weight basis, varied from 0.5 × 104 to 5 × 105. The levels of 210Po specific activity in molluscs and pelagic fishes anchovy and sprat were the highest among the investigated species of the Black Sea biota. Concentration factors (CF) of 210Po, estimated on a wet weight basis, reached 1.5 × 103 for macrophytes, 4 × 103 for total zooplankton, 103–104 for the entire fishes depending on their ecological groups affiliation and (0.7–6.0) × 104 for molluscs. So, the ability of the Black Sea biota to accumulate the natural radionuclide 210Po is comparable with that of similar species from others marine and oceanic areas

Природный радионуклид ²¹⁰Po в моллюсках Чёрного моря

Исследована способность 5 видов моллюсков Чёрного моря, обитающих в Cевасто-польских бухтах, аккумулировать ²¹⁰Po. Концентрации ²¹⁰Ро в этих гидробионтах варьируют в широких пре-делах и зависят от типа их питания. Самые высокие из них определены в гигантской устрице, а самые низкие – в нане. Аккумулирование ²¹⁰Po мидиями зависит от сырой массы их мягких тканей (WW), стадий репродуктивного цикла и условий обитания. Подобные зависимости отмечены для гигантской устрицы. Коэффициент накопления (CF) ²¹⁰Po для черноморских моллюсков варьирует от 7x10³ до 5.6x10⁴, что находится в согласии с усреднёнными данными для моллюсков из других регионов Мирового океана (3x10⁴).²¹⁰Po accumulation by five species of the Black Sea molluscs inhabiting the Sevastopol bays was studied. ²¹⁰Ро concentrations in investigated mollusks vary widely and depend on the type of their nutrition. The highest concentration was found in the Far-Eastern giant oyster and the lowest one – in nana. ²¹⁰Po accumulation by the Black Sea mussels depends on their individual wet weight (WW), the stages of maturity of the gonads and inhabitancy condition. Such dependences were found for the Far-Eastern giant oyster. Concentration Factors (CF) of ²¹⁰Po for the Black Sea molluscs vary from 7x10³ to 5.2x10⁴. This is in good agreement with World Ocean average value for ²¹⁰Po CF for molluscs which equals 3x10⁴

Goffin's Cockatoos (Cacatua goffiniana) Can Solve a Novel Problem After Conflicting Past Experiences

Novel problems often partially overlap with familiar ones. Some features match the qualities of previous situations stored in long-term memory and therefore trigger their retrieval. Using relevant, while inhibiting irrelevant, memories to solve novel problems is a hallmark of behavioral flexibility in humans and has recently been demonstrated in great apes. This capacity has been proposed to promote technical innovativeness and thus warrants investigations of such a mechanism in other innovative species. Here, we show that proficient tool—users among Goffin's cockatoos—an innovative tool—using species—could use a relevant previous experience to solve a novel, partially overlapping problem, even despite a conflicting, potentially misleading, experience. This suggests that selecting relevant experiences over irrelevant experiences guides problem solving at least in some Goffin's cockatoos. Our result supports the hypothesis that flexible memory functions may promote technical innovations

STM and STS investigation of few wall carbon nanotubes containing non-hexagonal carbon rings

International audienceWe performed scanning tunneling microscopy (STM) measurements on few wall carbon nanotubes that exhibited changing diameter. Such change in the diameter may occur if non-hexagonal carbon ring configurations are introduced in the nanotube walls. A few-walled nanotube knee of 4 degrees, with different diameter values on the two sides of the knee was imaged by STM. Theoretical model structures [J. Han et al., Phys. Rev. B 57 (1998) 14983] of single wall carbon nanotubes show that a bend of 4° may occur when a pentagonal and a heptagonal carbon ring is incorporated side by side in the hexagonal nanotube structure (i.e. "fused defect"). Scanning tunneling spectroscopic (STS) measurements show that additional electronic states are present in the energy gap in the region where the bend occurs. We also performed STS measurements on a single-wall nanotube with a conical tip. In agreement with theory, the results show that the energy gap in the tapered end is larger than in the nanotub