Spatial distribution of introduced brook trout Salvelinus fontinalis (Salmonidae) within alpine lakes: evidences from a fish eradication campaign

Brook trout Salvelinus fontinalis have been used worldwide to stock fishless alpine lakes, negatively affecting native biota. Understanding its spatial ecology in invaded ecosystems can provide information to interpret and contrast its ecological impact. We opportunistically used capture points of brook trout gillnetted during an eradication campaign to assess the distribution patterns of four unexploited populations inhabiting high-altitude lakes. The main eradication method implies the use of many gillnets with several mesh sizes, which are selective for different fish sizes. For each lake we drew six capture maps associated with as many different mesh sizes, and we tested whether the distance from the coastline (which in alpine lakes is a reliable proxy of the most important spatial gradients, e.g. depth, temperature, prey availability, lighting conditions) influences the proportion of captured fish belonging to different size classes and the number of fish captured by the nets with different mesh sizes. To interpret the results, we also provide a cartographic description of the lakes’ bathymetry and littoral microhabitats. We found (1) a negative relationship between brook trout distribution and the distance from the coastline in all of the size classes, lakes and mesh sizes; (2) that large brook trout can thrive in the lakes’ center, while small ones are limited to the littoral areas; and (3) that the distance from the coastline alone cannot explain all the differences in the catch densities in different parts of the lakes. As in their native range, introduced brook trout populations also have littoral habits. Microhabitats, prey availability and distance from the spawning ground are other likely factors determining the distribution patterns of brook trout populations introduced in alpine lakes. The obtained results also provide useful information on how to plan new eradication campaigns

Valuasi Sumberdaya Air (Studi Kasus Kawasan Mata Air Tataneyan di Kelurahan Kinilow I, Kecamatan Tomohon Utara, Kota Tomohon)

This study aims to determine how how big the valuations of water in the spring Tataneyan located in the Village Kinilow I, District of North Tomohon, Tomohon, by using the concept of economic valuation to calculate the value of the utilization of water resources directly or indirectly. This study was conducted from October to December 2016, using primary and secondary data with sampling technique simple random sampling method and the respondents as many as 30 people. Analysis of the data used is quantitative analysis to identify the value of the value of benefits in the area of water resources in the waters Tataneyan value direct use for domestic households and public bath are also value the presence of fish breeding and agricultural irrigation water spinach. The results showed that the area of the springs Tataneyan have a total economic benefit value of Rp. 1.586.715.372/year. By calculating the average value of the obtained surplus WTP consumers showed the overall consumer receives more benefits than the actual price that is able to pay in exploiting springs Tataneyan. The total value of economic benefits can be used as a reference for local communities in the utilization and management of water in the spring Tataneyan

Stochastic perturbations of convex billiards

We consider a strictly convex billiard table with C 2 boundary, with the dynamics subjected to random perturbations. Each time the billiard ball hits the boundary its reflection angle has a random perturbation. The perturbation distribution corresponds to the physical situation where either the scale of the surface irregularities is smaller than but comparable to the diameter of the reflected object, or the billiard ball is not perfectly rigid. We prove that for a large class of such perturbations the resulting Markov chain is uniformly ergodic, although this is not true in general.Fil: Markarian, R.. Universidad de la Republica. Facultad de Ingeniería; UruguayFil: Trivellato Rolla, Leonardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Investigaciones Matemáticas "Luis A. Santalo". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Matemáticas "Luis A. Santalo"; ArgentinaFil: Sidoravicius, V.. Jardim Botânico; BrasilFil: Tal, F. A.. Universidade de Sao Paulo; BrasilFil: Vares, M. E.. Universidade Federal do Rio de Janeiro; Brasi

Omineca Miner, January, 02, 1915

BACKGROUND AND AIMS: Immature platelet fraction (IPF) represents the quote of younger and larger sized circulating platelets, a potential marker of platelet reactivity and major cardiovascular events. We aimed to assess the relationship between IPF levels and the prevalence and extent of coronary artery disease (CAD) in patients undergoing coronary angiography. METHODS: A cohort of consecutive patients undergoing coronary angiography in a single centre were included. Significant CAD was defined as at least 1 vessel stenosis >50%, while severe CAD was defined as left main and/or three-vessel disease. IPF levels were measured at admission by routine blood cells count (A Sysmex XE-2100). RESULTS: We included 1789 patients, divided according to quartiles values of IPF. IPF levels were directly related to active smoke (p = 0.02), and non-acute coronary syndrome as indication to angiography (p < 0.001), higher levels of haemoglobin and uric acid (p < 0.001, respectively) and lower platelet count (p = 0.003). Angiographic features did not significantly differ according to quartiles values of IPF, but for a lower degree of TIMI flow in patients with a higher percentage of reticulated platelets (p = 0.01) and a higher rate of lesions involving bifurcations (p = 0.05). IPF levels did not affect the prevalence of CAD (77% vs. 82.2% vs. 79.1% vs. 75.6%, p = 0.34, adjusted OR [95% CI] = 0.93 [0.82-1.05], p = 0.22), nor of severe left main/three-vessel CAD (28.5% vs. 34.4% vs. 32.2% vs. 33.1%, p = 0.27; adjusted OR [95% CI] = 0.99 [0.90-1.1], p = 0.88). CONCLUSIONS: The present study shows that among patients undergoing coronary angiography, the immature platelet fraction (IPF) is not associated with the prevalence and extent of coronary artery disease, and, therefore, should not be overlooked as a marker of coronary atherosclerosis

Fixation for Distributed Clustering Processes

We study a discrete-time resource flow in $Z^d$, where wealthier vertices attract the resources of their less rich neighbors. For any translation-invariant probability distribution of initial resource quantities, we prove that the flow at each vertex terminates after finitely many steps. This answers (a generalized version of) a question posed by van den Berg and Meester in 1991. The proof uses the mass-transport principle and extends to other graphs