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Experimental results on the nature-like fishway induced flow field and its relation to fish behaviour are presented. A rocky-ramp with 5% slope was built along a8.9mx0.9mx0.6m laboratory flume, and acoustic Doppler velocity measurements were taken in a grid with 186 points for low, middle, and high discharges. The flow is characterized applying spatial and point analysis techniques. Point analysis consistently shows that the boulder to boulder distance is small enough to disrupt turbulent coherent structures. At boulder wakes no predominance of sweep and ejection events occur, evidencing a good resting place for fish migration. The nature-like rocky-ramp offers a diversity of flow conditions controlled by the boulders geometry that might allow a variety of fishes to develop their preferred paths characterized by flow properties with different magnitudes depending on the particular species. Obtained results compare well with similar ones reported for other standard fishways. Key words: ADV, fish habitat, fish passage, flow, nature-like fishways, turbulence. Cet article presente les resultats d'experiences concernant le champ de courant induit dans une passe migratoire d'aspect naturel et sa relation avec le comportement des poissons. Une rampe rocheuse ayant une pente de5%aete construite le long d'un canal jaugeur de laboratoire mesurant 8,9 x 0,9 x 0,6 m; des mesures de vitesse ont ete prises au debitmetre acoustique selon une grille de 186 points a des debits faibles moyens et eleves. L'ecoulement est caracterise en appliquant des techniques d'analyse spatiale et par points. L'analyse par points montre de maniere uniforme que la distance de rocher a rocher est suffisamment petite pour perturber les structures coherentes de turbulence. Il n'y a aucune predominance de balayage et d'ejection dans les sillages des rochers, prouvant qu'il s'agit d'un bon endroit de repos pour les poissons en migration. La rampe rocheuse d'aspect naturel offre une diversite de conditions d'ecoulement controlees par la geometrie des rochers, ce qui pourrait permettre a plusieurs especes de poissons de developper leur chemin prefere selon les proprietes d'ecoulement de differentes amplitudes propres aux especes particulieres. Les resultats obtenus se comparent bien a d'autres resultats similaires rapportes pour d'autres passes migratoires standards. [Traduit par la Redaction] Mots-cles : debitmetre acoustique, habitat du poisson, passe migratoire, ecoulement, passes migratoires d'aspect naturel, turbulence., 1. Introduction Fishways are hydraulic structures enabling fish to negotiate river obstructions such as dams, weirs, and under-road culverts. According to their design, one can distinguish standard and nature-like fishways. [...]

This note presents the results of turbulence measurements in the impinging region of a circular jet of diameter d with a Reynolds number of 105 impinging on a smooth wall located at a distance H equal to 18.5d. Even though the impinging region starts approximately at x/H = 0.860 (where x is the distance from the nozzle), the mean velocity profiles were found to be similar for xlH up to about 0.930 when normalized by the local maximum value. The normalized profiles of the turbulent shear stress and normal stresses in the axial, radial, and circumferential directions were also found to be similar. The variation of the scales for these turbulence profiles was found to be gradual for x/H up to about 0.960 and then rapid near the impinging wall. The corresponding length scales also showed a similar type of variation. The measurements also show that turbulence in the impinging jet drops significantly very near the impinging wall. Key words: circular jet, impinging region, measurement, turbulence. Ceite note presenle les resultals de mesures de turbulence dans la region d'incidence d'un jet circulaire de diametre d et ayant un nombre de Reynolds de I05 frappant un mur lisse silue a une distance H egale a 18,5;/. Bien que la region de frappe debute a environ x/H = 0,86, les profils moyens de vitesse se sont reveles similaires pour un rapport x/H jusqu'a environ 0,93 lorsque normalise par la valeur maximale locale. Les profils normalises de la tension de Reynolds et les contraintes normales dans les directions axiales. radiales et circonferentielles se sont egalement revelees similaires. La variation des echelles de ces profils de turbulence se sont revelees graduelles pour un rapport x/H jusqu'a environ 0,96, puis rapide pres du mur de frappe. Les echelles de longueur correspondantes montrent egalement un type similaire de variation. Les mesures montrent que la turbulence dans les jets incidents chute de maniere importante lorsqu'ils sont tres pres du mur de frappe. Mots-cles: jet circulaire, region de frappe. mesure, turbulence., Introduction The impingement of a turbulent jet on a solid surface is important for a number of engineering applications, like jets issuing from hydraulic structures and impinging on erodible beds [...]

The effect of ion implantation including ion species (N(super +)(sub 2) and C(sub 3)H(super +)(sub 8)) and the fluences (1 X 10(super 14) -5 X10(super 15 ions/cm(super 2)) on the surface energy of ultrahigh molecular weight polyethylene (UHMWPE) was investigated. The total surface energy increases significantly after implanting the fluence of 1 X 10(super 14)ions/cm(super 2) regardless of ion species, then, the total surface energy slightly increases for N(super +)(sub 2) implanted UHMWPE and decreases slightly for C(sub 3)H(super +)(sub 8) ) implanted UHMWPE with a further increase of fluence.

OBJECTIVE: To compare the therapeutic effects of red peony root decoction, a compound traditional Chinese herbal medicine, and rhubarb in treating severe acute pancreatitis (SAP). METHODS: A total of 96 [...]

With the development of new emerging technologies, many objects in scientific research and engineering are of sub-micrometer and nanometer size, such as microelectronics, micro-electro-mechanical systems (MEMS), biomedicines, etc. Therefore, thermal conductivity measurements with sub-micrometer resolution are indispensable. This paper reports on the imaging of various micrometer and sub-micrometer size surface variations using a scanning thermal microscope (SThM). The thermal images show the contrasts indicating the differences of the local thermal conductivity in the sample. Thermal resistance circuits for the thermal tip temperature are developed to explain the heat transfer mechanism between the thermal tip and the sample and to explain the coupling between the local thermal conductivity and the topography in the test results. [ABSTRACT FROM AUTHOR]

Background: Elective frozen-embryo transfer has been shown to result in a higher live-birth rate than fresh-embryo transfer among anovulatory women with the polycystic ovary syndrome. It is uncertain whether frozen-embryo transfer increases live-birth rates among ovulatory women with infertility., Methods: In this multicenter, randomized trial, we randomly assigned 2157 women who were undergoing their first in vitro fertilization cycle to undergo either fresh-embryo transfer or embryo cryopreservation followed by frozen-embryo transfer. Up to two cleavage-stage embryos were transferred in each participant. The primary outcome was a live birth after the first embryo transfer., Results: The live-birth rate did not differ significantly between the frozen-embryo group and the fresh-embryo group (48.7% and 50.2%, respectively; relative risk, 0.97; 95% confidence interval [CI], 0.89 to 1.06; P=0.50). There were also no significant between-group differences in the rates of implantation, clinical pregnancy, overall pregnancy loss, and ongoing pregnancy. Frozen-embryo transfer resulted in a significantly lower risk of the ovarian hyperstimulation syndrome than fresh-embryo transfer (0.6% vs. 2.0%; relative risk, 0.32; 95% CI, 0.14 to 0.74; P=0.005). The risks of obstetrical and neonatal complications and other adverse outcomes did not differ significantly between the two groups., Conclusions: The live-birth rate did not differ significantly between fresh-embryo transfer and frozen-embryo transfer among ovulatory women with infertility, but frozen-embryo transfer resulted in a lower risk of the ovarian hyperstimulation syndrome. (Funded by the National Key Research and Development Program of China and the National Natural Science Foundation of China; Chinese Clinical Trial Registry number, ChiCTR-IOR-14005406 .).