19 research outputs found
Trophodynamic and biogeochemistry in the annual sea-ice at Terra Nova Bay (Ross Sea, Antarctica).
Microbial functional genes enriched in the Xiangjiang River sediments with heavy metal contamination
Istituzioni, Diseguaglianza ed Economia Sommersa: quale relazione?
Quaderno 24/2008 Dipartimento di Scienze Economiche, Matematiche e Statistiche. Università di Foggi
Maximum aerobic power, lower limb explosive strength and isokinetic peak torque in chilenean professional and college soccer players
El fútbol es un deporte que solicita de acuerdo a sus caracterÃsticas fisiológicas, desempeño aeróbicoanaeróbico, además de fuerza y potencia muscular. Con el propósito de determinar caracterÃsticas funcionales en futbolistas profesionales Chilenos y compararlas con jugadores seleccionados universitarios, se obtuvo una muestra compuesta por 40 futbolistas profesionales y 19 seleccionados universitarios. Se determinó su Vo2 máx, Squat Jump (SJ), Counter Movement Jump (CMJ), Abalakov (ABAL) y el peak de torque isocinético para la extensión de rodilla a velocidades angulares de 60°/s, 180°/s y 300°/s. Los resultados arrojaron un Vo2 máx de 56,2±5,7 mlO2/min/kg, para los profesionales y de 50,4±4,06 mlO2/ min/kg para los universitarios (p<0,05). Para SJ el valor fue de 36,2±2,7 cm y 30,6±3,2 cm; para CMJ fue de 41,4±4,1cm y 35,8±3,5 cm; para ABAL fue de 48,5±4,6 cm y 41,6±3,7 cm para profesionales y universitarios respectivamente (p<0,05). El peak de torque promedio de las extremidades inferiores fue para 60°/s de 220,6±29,7 Nm y 195±30,5 Nm; para 180°/s de 148±18,7 Nm y 135,7±19,1 Nm; para 300°/s fue de 113,3±15,9 Nm y 101,8± 16,3 Nm para profesionales y universitarios respectivamente. Hubo diferencia significativa en 60°/s y 300°/s (p<0,05). Los valores de Vo2 máx se encuentran para los profesionales en el rango inferior reportado por otras investigaciones. Asà mismo ocurre con el peak de torque isocinético para 60°/s y 180°/s. En cuanto a los valores de SJ y CMJ, según los reportes de datos de C. Bosco, los jugadores están en un nivel similar a otros jugadores profesionales internacionales. En conclusión, para las variables estudiadas, los jugadores profesionales presentan en general mejores valores que los seleccionados universitarios. Sin embargo, en el contexto internacional, los valores de los profesionales son más bajos.Soccer is a sport that requires according to their physiological characteristics, aerobic-anaerobic performance, as well as muscle strength and power. To determine functional characteristics in Chilean professional soccer players and compare them with college soccer players, 40 professional soccer players and 19 college soccer players were evaluated. It was determined his Vo2 max, Squat Jump (SJ), Counter Movement Jump (CMJ), Abalakov (ABAL) and peak torque to the knee extension of isokinetic at speeds of 60 ° / s, 180 ° / s and 300 ° / S. The results showed a Vo2 max of 56.2 ± 5.7 mlO2/min/kg, for professionals and 50.4 ± 4.06 mlO2/min/kg for college players (p <0.05). For SJ value was 36.2 ± 2.7 cm, 30.6 ± 3.2 cm; for CMJ was 41.4 ± 4.1 cm, 35.8 ± 3.5 cm; for ABAL was 48 , 5 ± 4.6 ± 3.7 cm and 41.6 cm for professionals and college players respectively (p <0.05). The average peak torque of the lower extremities was to 60 ° / s 220.6 ± 29.7 Nm and 195 ± 30.5 Nm; to 180 ° / s was 148 ± 18.7 Nm and 135.7 ± 19.1 Nm; to 300 ° / s was 113.3 ± 15.9 Nm and 101.8 ± 16.3 Nm for professionals and college players respectively. There was a significant difference in 60 ° / s and 300 ° / s (p <0.05). Vo2 max values are for professionals in the lower range reported by other research. It also happens to the peak torque isokinetic to 60 ° / s and 180 ° / s. With regard to the values of SJ and CMJ, according to reports data C. Bosco, the players are at a level similar to other professional players. In conclusion, for the variables studied, professional players show highest values compared to college players. However, in the international context, the values of the professionals are lower.Sin financiaciónNo data 200
Molecular tools for the analysis of DNA in marine environments
2: 1-22 Spinger Verlag. Berlin
Monitoring groundwater characteristics by means of a multi-parametric probe and sampling device
Structural and functional properties of microbial communities in the annual sea-ice at Terra Nova Bay (Ross Sea – Antarctica).
Studies on the chemical and biological properties of annual pack ice at a coastal station in Terra Nova Bay (74°41.72'S, 164°11.63'E) were carried out during austral spring at 3-day intervals from 5 November to 1 December 1997. Temporal changes of
nutrient concentrations, algal biomasses, taxonomic composition, photosynthetic pigment spectra and P±E relationships were studied. Quantity, composition and degradation rates of organic matter in the intact sea ice were also investigated. In addition, microcosm experiments were carried out to evaluate photosynthetic and photo-acclimation processes of the sympagic flora in relation to different light regimes. High concentrations
of ammonia were measured in four ice-cores (weighted
mean values of the cores ranged from 4.3 ± 1.9 uM to
7.2 ± 3.4 uM), whereas nitrate and phosphate displayed
high concentrations (up to 35.9 uM and 7.6 uM, respectively) only in the bottom layer (135±145 cm depth).
Particulate carbohydrate and protein concentrations in
the intact sea ice ranged from 0.5 to 2.3 mg l-1 and 0.2 to 2.0 mg l-1, respectively, displaying a notable accumulation of organic matter in the bottom colored layer, where bacterial enzymatic activities also reached the highest values. Aminopeptidase activity was extremely high (up to 19.7 uM l-1 h-1 ± 0.05 in the bottom layer),suggesting a rapid turnover rate of nitrogen-enriched
organic compounds (e.g. proteins). By contrast, bacterial secondary production was low, suggesting that only a very small fraction of mobilized organic matter was converted into bacterial biomass (<0.01%o). The sympagic autotrophic biomass (in terms of chlorophaeopigments) of the bottom layer was high, increasing
during the sampling period from 680 to 2480 lg l-1.
Analyses of pigments performed by HPLC, as well as microscope observations, indicated that diatoms dominated bottom communities. The most important species were Amphiprora sp. and Nitschia cfr. stellata. Bottom sympagic communities showed an average PB max of 0.12 mgC mg Chl-1 and low hotoadaptation index (Ek = 18 uE m-2 s-1, Em = 65 uE m-2 s-1). Results of the microcosm experiment also indicated that communities were photo-oxidized when irradiance exceeded
100 uE m-2 s-1. This result suggests that microautotrophs inhabiting sea ice might have a minor role in the pelagic algal blooms
Imbalance between phytoplankton production and bacterial C demand in relation to mucilage formation in the Northern Adriatic Sea.
Microbial loop malfunctioning in the annual sea ice at Terra Nova Bay (Antarctica)
We investigated organic carbon quantity and
biochemical composition, prokaryotic abundance, biomass
and carbon production in the annual and platelet sea ice of
Terra Nova Bay (Antarctica), as well as the downward
fluxes of organic matter released by melting ice during
early spring. Huge amounts of biopolymeric C accumulated
in the bottom layer of the ice column concomitantly
with the early spring increase in sympagic algal biomass.
Such organic material, mostly accounted for by autotrophic
biomass, was characterised by a high food quality and was
rapidly exported to the sea bottom during sea ice melting.
Prokaryote abundance (up to 1.3 9 109 cells L-1) and
extracellular enzymatic activities (up to 24.3 lM h-1 for
amino-peptidase activity) were extremely high, indicating
high rates of organic C degradation in the bottom sea ice.
Despite this, prokaryote C production values were very low
(range 5\u201330 ng C L-1 h-1), suggesting that most of the
degraded organic C was not channelled into prokaryote
biomass. In the platelet ice, we found similar organic C
concentrations, prokaryote abundance and biomass values
and even higher extracellular enzymatic activities, but
values of prokaryote C production (range 800\u2013
4,200 ng C L-1 h-1) were up to three orders of magnitude
higher than in the intact bottom sea ice. Additional field
and laboratory experiments revealed that the dissolved
organic material derived from algae accumulating in the
bottom sea ice significantly reduced prokaryote C production,
suggesting the presence of a potential allopathic
control of sympagic algae on prokaryote growth