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Ecuador has reported as main insect pests in lemon: Phyllocnistis citrella Stainton (Lepidoptera: Gracillariidae), Aleurothrixus floccosus Maskel (Hemiptera: Aleyrodidae), Toxoptera aurantii Boyer de Fonscolombe (Homoptera: Aphididae); natural enemies of these pests, is presented as an alternative for biological control. The objective was to assess the population dynamics of the main lemon pests and their parasitoids in the towns of Colón and Riochico, province of Manabí, Ecuador. The collected samples were analyzed with the R software V3.4.2. Bivariate analyzes were carried out comparing the population of pests and their parasitoids by localities, the assumption of normality was verified with Kolmogorov-Smirnov tests for the total number of individuals of pest populations and the percentage of parasitoids, the independent samples t-test was used and Pearson's correlation analysis was performed for the populations of pests and their parasitoids. Five species of parasitoids were identified in two localities: Encarsia nigricephala (Hymenoptera: Aphelinidae) and Eretmocerus sp. (Hymenoptera: Aphelinidae) corresponded to A. floccosus; Aphidius sp. (Hymenoptera: Braconidae) with Diaretus sp. (Hymenoptera: Braconidae) were found in T. aurantii; and A. citrícola Logvinovskaya (Hymenoptera: Encyrtidae) for P. citrella. There was no correlation between P. citrella and A. citricola in the localities evaluated. For the jurisdiction of Riochico, a significant correlation of -0.706 was reached between A. floccosus and E. nigricephala In the town of Colón, a significant direct correlation of 0.672 was observed between the parasitoids E. nigricephala and Eretmocerus sp. In addition, a significant correlation was obtained between the population of T. aurantii and the parasitoid Diaretus sp., whose value was - 0.624 for the town of Riochico. [ABSTRACT FROM AUTHOR]

The key factor in creating value in companies and banks is the capital structure and financing method so that companies are moving towards creating value through debt control and the use of proper financing. Therefore, the present study was conducted to investigate the effect of financial leverage on the stock price volatility trend in listed companies in Tehran Stock Exchange for the period 2011-2018 using systematic elimination method. The results of data analysis showed that financial leverage capital has significant effect on the trend of stock price volatility in listed companies in Tehran Stock Exchange. [ABSTRACT FROM AUTHOR]

This research was conducted in two fields of Ipomoea purpurea (L.) Roth on the cliffs of Miraflores-Lima: "San Martín" and "Armendáriz", with the objectives to determine the population fluctuation of Tetranychus sp. and Euseius stipulates (Athias-Henriot) on the leaves of I. purpurea, and to determine the effect of the release of E. stipulatus into the Tetranychus sp. population. The evaluation lasted one year, from October 2013 to October 2014. The methodology consisted in dividing each sector into five areas and evaluating weekly and randomly, 20 leaves (upper and lower side), for a total of 100 leaves per sector. The higher infestation occurred in San Martin, with a density of 74.9 mites per leaf at 24.1 °C and 76.4% of relative humidity. In the Armendáriz sector, Tetranychus sp. presence was lower, with a density of 11.2 individuals / leaf at 23.7 °C and at 76.3% of relative humidity. In general, the higher peaks of Tetranychus sp. occur in summer when temperatures are higher and their cycles are shorter. Nevertheless, it was demonstrated that it has a damaging affect all year. Through the liberations, the predator action of E. stipulatus over the different stadiums of Tetranychus sp. was successfully demonstrated. [ABSTRACT FROM AUTHOR]

The availability of the variable space-temporal in the description hydrographic is fundamental in the climatization, hydrological studies e prevention of environmental risks. The objective of this work is to discuss the rainfall distribution in the Madeira River basin, verifying it's areas of greatest and/or least water potential. The watershed of the Madeira River is located in the north of Brazil, most influential of the Amazon, with rains of 1650-3050 mm and very diverse soil. The rainfall data comes from ANA and the SST data was acquired from NOAA. The positive SST anomalies for the Pacific were verified, and in these same waters, negative values (SST). In the Atlantic Ocean it is observed the years of Positive and Negative Dipole. The rainiest quarter is January (300.6 mm), February (291.8 mm) and March (286.8 mm) and the least rainy is June (47.0 mm), July (29.4 mm) and August (36.7 mm). In the rainy season (Nov-Abr) the water supply is favored in the low course of the Madeira river. The dry season (Mai-Out) is characterized by a hydrological deficit. The lowest rains are south-southwest (1,120.5-1868.7 mm). In the central region of (1,868.7-2,192.6 mm). The major rain are concentrated to the northeast (2,501,1- 3,087,3 mm). The upstream flows (Rio Beni) presented in the majority of the period peaks superior to 4000 m³/s. The impact that rainfall causes on the water supply of a basin is crucial for the preservation of this environmental reservoir, since it influences in several sectors in the socioeconomic sphere. [ABSTRACT FROM AUTHOR]

Observations on population fluctuations of Pinnaspis aspidistrae (Signoret), Fiorinia fioriniae (Targioni Tozzetti), Chrysomphalus aonidum (Linnaeus) and their parasitoids in avocado's crop located in the Agrarian University of La Molina were made. Plots were divided into five sectors, in which five trees were selected randomly in which 200 leaves (face and underside) were evaluated in stratums (middle and lower third) every week from July 16th to December 17th, 2014. The highest population of P. aspidistrae were observed in the face of the leaves in the lower third, while the highest population of F. fioriniae were detected at the underside of the leaves. Chrysomphalus aonidum was observed in the face and the underside of the leaves from the middle and lower third, their population being higher on the face of the leaves. The highest levels were recorded in September in all the cases. Aphytis sp. group chrysomphali, Encarsia lounsburyi (Berlese & Paoli) and Encarsia citrina (Craw) were identified as the parasitoids of C. aonidum, Encarsia lounsburyi (Berlese & Paoli) as parasitoid of F. fioriniae and Arrenophagus sp. as P. aspidistrae's parasitoid. [ABSTRACT FROM AUTHOR]

The article presents the results to evaluate the algorithm load balancing own LCM of MPLS to be used as load distributing through various links on switched networks generalized multiprotocol label (GMPLS), this in order to avoid saturating primary data transport route between the source and destination. The methodology used included the implementation of the algorithm in C + + to evaluate their performance in discrete event simulator NS-2 and from the results generate an optimization proposal that would raise their performance. It can be noted from the metrics evaluated (throughput, jitter, level balancing and stability) that LCM is a good candidate as a distributor do load used in GMPLS infrastructure. [ABSTRACT FROM AUTHOR]

The phenomena of alteration of a digital signal that interfere with optimal performance, are present regardless of the number of filters, or dynamic elements electronic devices of high quality and environmental isolates that are available. Because of this, it is essential to have a proper technical management in managing the changes that may occur to the original signal. To correct and align the tax rates on incoming teams high order multiplexing is the applicability of the principles of positive justification or insertion of bits or voids that regulate this speed read-write. On the other hand, data transmission, we have a phenomenon known as jitter or jitter, even causing a shift in the ideal position of the bit received with reference to their nominal flanks, which leads to an inaccuracy final signal from the original income. No digital system must be presumed as immune to these changes. [ABSTRACT FROM AUTHOR]

The Scolytinae insects are commonly known as bark or ambrosial beetles because of their feeding habits. Among them, some species restrict their reproductive activity to a host plant or a small number of them, whereas others are highly polyphagous. In order to evaluate the population dynamics of Scolytinae species, populations of Xyleborus ferrugineus and X. affinis in ecosystems from Tabasco, Mexico were studied. The study was carried out from November 2010-July 2011, February 2010-January 2011 and 2007. The trapping methods used were alcohol traps, light traps and direct capture on their host plants. A total of 688 specimens of X. ferrugineus and 3 911 specimens of X. affinis were collected. The population dynamics of X. ferrugineus showed low size population in the studied ecosystems, without any marked seasonality. The highest population sizes were recorded both in dry season (March-May) and rainy season (September-December). Unlike the populations of X. ferrugineus, those of X. affinis were more abundant and showed the highest peaks during the rainy seasons (except in May at the Botanical Garden "José Narciso Rovisora"). Alcohol and light traps can be complementary methods for monitoring the populations of these types of insects. They occur most of the year and theirs population dynamics depends on food resources availability as well as environmental factors such as temperature and humidity. Judging by the observed abundance it is suggested that X. affinis has been adapted and exploited resources in a better way than X. ferrugineus in those ecosystems. Correlations between abundance and climatic factors had both positive and negative values. The results reflect the behavior of populations. However, a detail assessment of the biological and abiotic factors that influence the fluctuations of these insects is required. [ABSTRACT FROM AUTHOR]