285 research outputs found
Feeding behavior of brown trout, Salmo trutta fario, during spawning season in four rivers of Lar National Park, Iran
Brown trout, Salmo trutta fario, has a wide range of distribution in the north of Iran and in Karaj, Lighvanchai and Karun Rivers, but there is no report about its feeding behavior in some water resources including the Lar Natural Park. In order to study feeding behavior of this fish during spawning season, a survey was carried out in the rivers of Elarm, Aab-Sefid, Kamardasht and Delichayi in fall 2008. A total of 140 individuals of brown trout were caught by cast net and electro fishing. Mean weight and length of the samples were 130±79.5 g and 216.9±39 mm, respectively. The age of fish was 2 to 6 years and mean age was 3.02±1.3. The mean relative gut length (RLG) of samples was 0.86±1. It was found that brown trout fed on various preys (32 animal groups), that Chironomidae (88.6%), Simulidae (60%), Baetidae (51.4%) and Tipulidae (50%) have had the most frequency in the gut of brown trout. The proportion of food consumed by trout was Diptera 91.5% (Chironomidae pupa and larvae 85.8%), Coleoptera 6.4% and others 2.1%. Cannibalism was seen scarcely. In conclusion, brown trout consumes a wide range of food items in its spawning season. Therefore, it can be classified as euryphagous and carnivaorou
FLUVIAL LIMESTONE TUFFS FROM THE S. PORTUGAL (LOULE-TAVIRA) AND N. MOROCCO (TETUAN): COMPARISON AND ENVIRONMENTAL IMPLICATIONS
Limestone tuff deposits precipitated in fluvial environments are widespread in the northern Morocco and the S Portugal. These deposits represent environmental conditions prone for the carbonate precipitation mainly in areas of Mesozoic limestone substratum with active water seepage from the aquifers.
The mesoscopic and microscopic characteristics of tuff deposits from Tetouan (Morocco) and Loule and Tavira (Portugal) are very alike; namely on deposit types (e.g. phytoherm barriers; banded limestones with abundant vegetation macro-remains; carbonates precipitation as cement of some early alluvial conglomerates or interbedded alluvial deposits). The common textural features and macro-facies (e.g. banded calcite in regular layers ; moldic porosity; textures resulting from carbonate precipitation mediated by bacteriological activity) point to a similar origin of these limestone tuffs on both sides of Gibraltar Strait despite their slightly different climatic conditions that are influenced by the active inflow of surface Atlantic water towards the Mediterranean (for the Tetouan region) and by the Azores anticyclone (for the Loulé-Tavira region). The field observations show that the limestone tuffs precipitation is nowadays residual and radiocarbon dating of Portuguese deposits points to a chronological framework for their formation starting in the beginning of the post-Younger Dryas climatic recovery and ending around 2.5 ky BP. The oxygen stable isotopes data show a gradual change in the tuffs isotopic signature through the time interval during which the system remained active, without any particular record of climate events such as the 8.2 ka.
The available data and those from monitored modern pluvial characteristics allow the speculation on the parameters controlling the limestone tuffs deposition on both northern and southern sides of the Gibraltar Strait during the Holocene. The carbonate deposition on fluvial systems, such as the studied ones, probably depends on the precipitation / evaporation balance leading to the availability and turbulence of the flowing water along the streams.
Acknowledgments: This works was done with the financial support of the FCT Proc. 441.00 CNRST- MARROCOS and PTDC/CTE-GIX/117608/2010 projects and the SFRH/BD/62323/2009 grant
The Indirect Search for Dark Matter with IceCube
We revisit the prospects for IceCube and similar kilometer-scale telescopes
to detect neutrinos produced by the annihilation of weakly interacting massive
dark matter particles (WIMPs) in the Sun. We emphasize that the astrophysics of
the problem is understood; models can be observed or, alternatively, ruled out.
In searching for a WIMP with spin-independent interactions with ordinary
matter, IceCube is only competitive with direct detection experiments if the
WIMP mass is sufficiently large. For spin-dependent interactions IceCube
already has improved the best limits on spin-dependent WIMP cross sections by
two orders of magnitude. This is largely due to the fact that models with
significant spin-dependent couplings to protons are the least constrained and,
at the same time, the most promising because of the efficient capture of WIMPs
in the Sun. We identify models where dark matter particles are beyond the reach
of any planned direct detection experiments while being within reach of
neutrino telescopes. In summary, we find that, even when contemplating recent
direct detection results, neutrino telescopes have the opportunity to play an
important as well as complementary role in the search for particle dark matter.Comment: 17 pages, 10 figures, published in the New Journal of Physics 11
105019 http://www.iop.org/EJ/abstract/1367-2630/11/10/105019, new version
submitted to correct Abstract in origina
LEĂOMYOSARCOME UTERIN DE PRESENTATION INHABITUELLE
UtĂ©rin Leiomyosarcoma is rare [1.5]. It is likely conjunctiva and developed at the expense of mesenchymal elements of the myometrium. The uterus bicornis united cervical represents 39% of all uterine malformations [8]. The prevalence of these abnormalities is estimated at 0.5%. The association leĂŻomyosarcoma and uterine malformation still very exceptional. The purpose of our work is to study the unique combination from the clinical, paraclinical, pathological, and evolving therapeutic.Le lĂ©iomyosarcome utĂ©rin est une tumeur maligne, rare [1,5].Elle est de nature conjonctive et dĂ©veloppĂ©e aux dĂ©pens des Ă©lĂ©ments mĂ©senchymateux du myomĂštre. LâutĂ©rus bicorne uni cervical reprĂ©sente 39% de lâensemble des malformations utĂ©rines [8]. La prĂ©valence de ces malformations est estimĂ©e Ă 0,5%. Lâassociation leĂŻomyosarcome utĂ©rin et malformation utĂ©rine reste trĂšs exceptionnelle et ce du fait que la malformation utĂ©rine est de diagnostic prĂ©coce Ă un Ăąge jeune contrairement au leiomyosarcome utĂ©rin qui survient chez des femmes dâĂąge avancĂ©. Le but de notre travail est dâĂ©tudier Ă partir de notre observation cette association exceptionnelle sur le plan clinique, paraclinique, anatomopathologique, thĂ©rapeutique et Ă©volutif
Effects of moderate- vs. high-intensity interval training on physical fitness, enjoyment, and affective valence in overweight/obese female adolescents: a pre-/post-test study
OBJECTIVE
The aim of this study was to compare the effects of 12-week moderate-intensity interval training (MIIT) vs. high-intensity interval training (HIIT) on body composition, physical fitness, and psychological valence in overweight/obese (OW/OB) female adolescents.
PATIENTS AND METHODS
Thirty-eight OW/OB female students were randomized into HIIT (n=13), MIIT (n=13) or control (n=12) groups. The participants underwent a 12-week interval-training program at 100% to 110% and 60% to 75% of maximal aerobic speed for HIIT and MIIT, respectively. The control group kept their usual physical activity without completing the training program. Pre- and post-training measurements were performed to assess body composition, aerobic capacity, and anaerobic performance (using selected tests evaluating speed, jumping ability, and strength). Ratings of perceived exertion and the feeling scale were evaluated every three weeks. Enjoyment was measured at the end of the program. A two-way analysis of variance with repeated measurements was applied to test for "groupĂtime" interactions for body composition, physical fitness, and affective variables.
RESULTS
Significant "groupĂtime" interactions were detected for aerobic and anaerobic performance, body composition indices, and the feeling scale. HIIT resulted in more noticeable improvements in body composition and physical performance than MIIT, while no significant changes were found in the control group. Throughout the program, the feeling score has progressively increased in the MIIT group but decreased in the HIIT group. Ratings of the perceived exertion have increased in both groups, more noticeably in the HIIT group. At the end of the program, the MIIT group showed a higher enjoyment score.
CONCLUSIONS
Despite offering better body composition improvement and physical fitness enhancement, HIIT offered lesser enjoyment and affective valence than MIIT in OW/OB female adolescents. MIIT might be an alternative time-efficient protocol for improving health in this population
Modeling and Controlling Flow Transient in Pipeline Systems: Applied for Reservoir and Pump Systems Combined with Simple Surge Tank
When transient conditions (water hammer) exist, the life expectancy of the system can be adversely impacted, resulting in pump and valve failures and catastrophic pipe rupture. Hence, transient control has become an essential requirement for ensuring safe operation of water pipeline systems. To protect the pipeline systems from transient effects, an accurate analysis and suitable protection devices should be used. This paper presents the problem of modeling and simulation of transient phenomena in hydraulic systems based on the characteristics method. Also, it provides the influence of using the protection devices to control the adverse effects due to excessive and low pressure occuring in the transient. We applied this model for two main pipeline systems: Valve and pump combined with a simple surge tank connected to reservoir. The results obtained by using this model indicate that the model is an efficient tool for water hammer analysis. Moreover, using a simple surge tank reduces the unfavorable effects of transients by reducing pressure fluctuations
TeV Particle Astrophysics II: Summary comments
A unifying theme of this conference was the use of different approaches to
understand astrophysical sources of energetic particles in the TeV range and
above. In this summary I review how gamma-ray astronomy, neutrino astronomy and
(to some extent) gravitational wave astronomy provide complementary avenues to
understanding the origin and role of high-energy particles in energetic
astrophysical sources.Comment: 6 pages, 4 figures; Conference summary talk for "TeV Particle
Astrophysics II" at University of Wisconsin, Madison, 28-31 August 200
Impact of water application conditions on nitrogen leaching under furrow irrigation: Experimental and modelling approaches
Ultra-High Energy Cosmic Ray production in the polar cap regions of black hole magnetospheres
We develop a model of ultra-high energy cosmic ray (UHECR) production via
acceleration in a rotation-induced electric field in vacuum gaps in the
magnetospheres of supermassive black holes (BH). We show that if the poloidal
magnetic field near the BH horizon is misaligned with the BH rotation axis,
charged particles, which initially spiral into the BH hole along the equatorial
plane, penetrate into the regions above the BH "polar caps" and are ejected
with high energies to infinity. We show that in such a model acceleration of
protons near a BH of typical mass 3e8 solar masses is possible only if the
magnetic field is almost aligned with the BH rotation axis. We find that the
power of anisotropic electromagnetic emission from an UHECR source near a
supermassive BH should be at least 10-100 times larger then UHECR power of the
source. This implies that if the number of UHECR sources within the 100 Mpc
sphere is ~100, the power of electromagnetic emission which accompanies proton
acceleration in each source, erg/s, is comparable to the typical
luminosities of active galactic nuclei (AGN) in the local Universe. We also
explore the acceleration of heavy nuclei, for which the constraints on the
electromagnetic luminosity and on the alignment of magnetic field in the gap
are relaxed
Searches for Periodic Neutrino Emission from Binary Systems with 22 and 40 Strings of IceCube
Recent observations of GeV /TeV photon emission from several X-ray binaries have sparked a renewed interest in these objects as galactic particle accelerators. In spite of the available multi-wavelength data, their acceleration mechanisms are not determined, and the nature of the accelerated particles (hadrons or leptons) is unknown. While much evidence favors leptonic emission, it is very likely that a hadronic component is also accelerated in the jets of these binary systems. The observation of neutrino emission would be clear evidence for the presence of a hadronic component in the outflow of these sources. In this paper we look for periodic neutrino emission from binary systems. Such modulation, observed in the photon flux, would be caused by the geometry of these systems. The results of two searches are presented that differ in the treatment of the spectral shape and phase of the emission. The 'generic' search allows parameters to vary freely and best fit values, in a 'model-dependent' search, predictions are used to constrain these parameters. We use the IceCube data taken from May 31, 2007 to April 5, 2008 with its 22-string configuration, and from April 5, 2008 and May 20, 2009 with its 40-string configuration. For the generic search and the 40 string sample, we find that the most significant source in the catalog of 7 binary stars is Cygnus X-3 with a 1.8% probability after trials (2.10" sigma one-sided) of being produced by statistical fluctuations of the background. The model-dependent method tested a range of system geometries - the inclination and the massive star's disk size - for LS I+61 deg 303, no significant excess was found
- âŠ