Dominance of positivity of the Green's function associated to a perturbed polyharmonic dirichlet boundary value problem by pointwise estimates

Magdeburg, Univ., Fak. für Mathematik, Diss., 2015

Reward- and attention-related determinants of color selection in human visual cortex

Magdeburg, Univ., Fak. für Naturwiss., Diss., 2015

Determinants of global color-based attention : insights from electromagnetic brain recording in humans

Otto-von-Guericke-Universität Magdeburg, Fakultät für Naturwissenschaften, Univ., Dissertation, 2015

Optimal control of a Stefan problem with gradient-based methods in FEniCS

Otto-von-Guericke-Universität Magdeburg, Fakultät für Mathematik, Masterarbeit, 2016

Morphological phylogeny of the bat genus Platyrrhinus Saussure, 1860 (Chiroptera: Phyllostomidae) with the description of four new species / Paul M. Velazco.

n.s. no.105(2005)

Comparative study of wax glands in four Meliponini bees (Hymenoptera, Apidae) producing different quantities of wax

The developmental degree of the wax glands was compared in four Meliponini bees, that produce different quantities of wax. The histological data and height average of the wax epithelium during the time in which the maximum production of wax is expected, are in accordance with the rates of wax produced by the species. In Lestrimelitta limao (Smith, 1863) a species which has cleptobiotic habits, and frequently rob wax from the attacked colonies, the height of wax epithelium was the lowest among the studied species. The cells seem to show an abnormal vacuolated cytoplasm, in the phase in which they would be producing wax.

Estrutura floral das angiospermas usadas por Heliconius erato phyllis (Lepidoptera, Nymphalidae) no Rio Grande do Sul, Brasil

A field survey of flowering plants used as food resource by the adults of Heliconius erato phyllis (Fabricius, 1775) was carried out in four sites located in Rio Grande do Sul state, Brazil. Samples were taken in preserved areas of the Atlantic Rain and Myrtaceae forests, an Eucalyptus plantation, and an urban park. Adult feeding frequencies on flowers were registered monthly from December 1996 to May 1997, on plants located on previously marked 200 m long transects. Flowers on which H. erato phyllis fed in the field were collected, drawn and morphometrically characterized. Feeding was registered on flowers of twenty-three species, of which seventeen are new records for H. erato in Brazil . The use of a given plant varied among localities, as a function of its corresponding abundance. The most visited flowers were those of Lantana camara L. and Stachytarpheta cayennensis (Rich.) Vahl, followed by Dahliapinnata Voss in the urban site. The data suggest the existence of size and shape convergence between the proboscis and the small, tubular flowers upon which H. eratophyllis feeds. They also indicate that H. eratophyllis adults have an opportunistic nectar feeding / pollen gathering habit, using several of those flowers available in a given time and locality that fit such a morphometrical pattern. Since plant species of both primitive and derived families are used, there is no indication that phylogenetic constraints play a major role in this association, nor that color of flowers, growth pattern or size of the plants are relevant in determining their use by H. erato phyllis.

Late Mogollon communities: four sites of the Tularosa phase, western New Mexico / [by] Paul S. Martin, John B. Rinaldo [and] Eloise R. Barter.

v.49:no.1(1957)

Rare fishes of the deep-sea genus Halieutopsis : a review with descriptions of four new species (Lophiiformes; Ogcocephalidae) : a contribution in celebration of the distinguished scholarship of Robert F. Inger on the occasion of his sixty-fifth birthday /

n.s. no.44(1988)

Temperature, urbanization and body color polymorphism in South Brazilian populations of Drosophila kikkawai (Diptera, Drosophilidae)

Body color polymorphism of urban populations of cosmopolite fly Drosophila kikkawai Burla, 1954 was investigated in relation to its possible association with environmental temperature. Samples of D. kikkawai were collected in spring, summer, autumn and winter between 1987 to 1988, in zones with different levels of urbanization in the southern Brazilian city of Porto Alegre, Rio Grande do Sul. A clear association was observed between darker flies and both seasons with low temperatures and areas of low urbanization (where temperature is generally lower than in urbanized areas). Results of preliminary laboratory experiments involving six generations of flies grown in chambers at temperatures of 17º and 25ºC confirmed this tendency to a relationship between body color and temperature, with allele frequency of the main gene involved in body pigmentation changing over time.

Estágios de desenvolvimento gonadal de fêmeas do camarão-barba-ruça (Artemesia longinaris - Decapoda: Penaeidae)

The stages of gonadal development for the female of "barba-ruça" shrimp (Artemesia longinaris Bate, 1888) were characterized based on histological analysis. Four stages (immature, almost mature, ripe and spawned) were determined according to the structure and arrangement of cells in the ovary. Each stage corresponds macroscopically to a characteristic color, except stages I (immature) and IV (spawned), in which colors are very similar and can be distinguished only microscopically. The chromatic scale varies from white/translucent (stage I), neutral green (almost mature) to dark green (ripe). The mean size of cells was 56.9 µm (±3.5) (stage I), 127 µm (±2.6) (stage II) and 183 µm (±1.91) (stage III). The size frequency of cells was polimodal, and different cell stages were observed in ripe ovary, suggesting the occurrence of multiple spawning. The chromatic scale developed is an important tool for laboratory analysis, and can be easily used to identify the gonadal stages.

Composition of the family Didelphidae Gray, 1821 (Didelphoidea:Marsupialia), with a review of the morphology and behavior of the included four-eyed pouched opossums of the genus Philander Tiedemann, 1808 /

n.s. no.86(1997)

Spatio-temporal variation of the pink shrimp Farfantepenaeus paulensis (Crustacea, Decapoda, Penaeidae) associated to the seasonal overture of the sandbar in a subtropical lagoon

On the southern Brazilian coast, the penaeid pink shrimp Farfantepenaeus paulensis (Pérez-Farfante, 1967) is intensively captured by both artisanal and industrial fisheries. In the Ibiraquera Lagoon, artisanal fishing of juvenile stocks has declined sharply over the last 15 years. The traditional management methods used by fishermen are no longer sustainable due to conflicts with the demands of tourism and weak environmental and public agencies. The dynamics of the timing of the artificial opening and natural reformation of a sandbar across the mouth of the lagoon are regarded as a central socio-ecological problem. We evaluated the abundance and biomass variation of F. paulensis throughout the year and along a spatial gradient measured from the sandbar into the lagoon. We also explored the influence of opening the sandbar on the shrimp population. Samples were collected monthly from February 2004 to February 2005, using a 27 mm mesh cast net, in four different areas, with three sites being sampled per area. Small numbers of large shrimps were captured in the upper area, while greater biomass and abundance of small shrimps were observed near the sandbar, suggesting the role of the inner area as a refuge for growing. The highest records for biomass and abundance were recorded during warm months, regardless if the lagoon was open or closed by the sandbar. The Ibiraquera Lagoon could be more productive for fishermen if the sandbar opening was coincident to the period of natural post-larvae influx. Furthermore, coastal stocks could be improved by opening the sandbar again during summer in conjunction with fishing quotas.

Calliphorid fly (Diptera, Calliphoridae) attraction to different colored traps in the Tingua Biological Reserve, Rio de Janeiro, Brazil

The present study intended to analyze calliphorid attraction to traps painted in a variety of colors and the calliphorid constancy index in the Tingua Biological Reserve, Rio de Janeiro state, Brazil. The Diptera were collected monthly in the Reserve, between 2002 and 2005, totaling 24 samplings. Four traps containing sardines as bait were painted olive green, blood red, black, or white and exposed for 48 h at four equidistant points, 50 m from each other. To determine the calliphorid species constancy, the Bodenheirmer constancy index was used throughout the study. To analyze differences in the total abundance between species and in their color selection, an ANCOVA test with a significance level of 5 % and a Tukey post-test were used, considering the categories species and color as cofactors and climatic variables as co-variables (temperature, relative humidity and precipitation), since the samples were collected over two years. 10,444 insects were captured. Of these, 56 % belonged to the Calliphoridae family, totaling 13 species, with the most frequent species being Laneela nigripes (28.5 %), Hemilucilia semidiaphana (17 %), and Mesembrinella sp. (16.4 %). The other species had frequencies lower than 12 %. Nine species were considered constant, two accessories, and two accidental. The data indicated that the most frequent species presented significant differences between themselves concerning abundance over the captured months, however, the Tukey post-test indicated differences only between a few of them. The black trap presented the higher relative calliphorid frequency (27.34 %), followed by green (25 %), red (24.0 %), and white (23.7 %), although the species abundance in the different colored traps did not differ significantly among themselves. Therefore, there was no Calliphorid flies preference for any of the tested colors.