The Potential Benefits and Risks to the Environment in Using Bio-energy

Given the scarcity of oil reserves, renewable sources of energy have become important. The Brazilian government has established standards and policies to foment the use of bio-energy. Bio-fuels have widespread use and have been inserted into the national energy matrix to help sustainable development. It is necessary to establish the effectiveness of these government initiatives in preserving ecology; otherwise environmental harm such as the loss of biodiversity will increase. The objective of this paper is to identify and analyse, from a systems point of view, the potential benefits and risks to the environment which may arise from the use of bio-energy; whether its production is in agreement with the Brazilian constitution and whether its environmental impact is beneficial when it is exploited economically. It also examines the legal aspects of the National Energy Policy and the introduction of bio-diesel. We conclude that the place of bio-fuel in the Brazilian and the world’s energy matrix is irreversible and furthermore, that its role will increase sharply in the future.     

Reproductive biology of two species of Hyalella Smith, 1874 (Crustacea: Amphipoda: Hyalellidae) from southern Brazil

Reproduction is a critical event in the life cycle of animals, and a high amount of energy is allocated to it. The aim of this study was to characterize the reproductive biology of two recently described species of Hyalella from the north-east region of state of Rio Grande do Sul in southern Brazil. The specimens were collected during 12 months from a stream source (Hyalella georginae) and from a water reservoir (H. gauchensis), in Palmeira das Missões municipality, state of Rio Grande do Sul. Upon sampling, ovigerous females and pairs in precopulatory behaviour were separated into microtubes. In the laboratory, the cephalothorax length (CL in mm) of all specimens was measured. Male size at onset of sexual maturity was larger than that of the females, in both species. There was a correlation between the size of paired males and females: larger males carried larger females, in both Hyalella species. Precopulatory pairs were found throughout the year; however, H. georginae had a higher frequency in spring, and H. gauchensis in autumn. There was a positive correlation between the CL of ovigerous females and the number of eggs/juveniles. A reduction in the number of eggs throughout the embryonic development was observed in H. georginae. The average fecundity of H. georginae was significantly higher than H. gauchensis. The differences between the reproductive biology of these species may be related to the physical and environmental conditions at which they are exposed in their habitats.     

Breeding biology of the Sayaca Tanager (Thraupis sayaca) in southeast Brazil

ABSTRACT

Thraupis is a genus of the American endemic Thraupidae (subfamily Thraupinae), comprising seven species that inhabit tropical forests to urban centres. The Sayaca Tanager (Thraupis sayaca) is a disturbance-tolerant species of high representativeness in plant-frugivore networks, but information on its breeding biology is scarce and often restricted to non-systematic surveys. We studied the breeding biology of the T. sayaca, following 39 active nests in a periurban area of southeast Brazil during two breeding seasons (2017/2018, 2018/2019). The breeding season ranged from early September to middle December, and the nests were placed in native and exotic plants and human buildings (nest height above ground: 3.35 ± 1.73 m, mean ± SD). Only females incubated and brooded, but both adults built the nests, fed the nestlings, and removed their faecal sacs. Clutch size was 2.86 ± 0.38 eggs and nest attentiveness was 71.2%. The incubation and nestling periods were, respectively, 13.4 and 17.4 days. Males and females did not differ on nestling provisioning and nest sanitation rates. Nestling provisioning (13.35 ± 6.25 trips/hour) increased with nestling age, while mean brooding time was 37.2% and decreased with nestling age. Apparent nest success was 38.7%, and nest survival according to the Mayfield method was 27.2%. Five nests (20.8%) were parasitised by the Shiny cowbird (Molothrus bonariensis), and we recorded five events of nest-site reuse. We concluded that the most remarkable breeding traits of T. sayaca in comparison with close-related tanagers are the use of anthropogenic nest sites, the higher clutch size and number of feeding trips, and the longer nestling period.     

Heterospecific mating between distantly related species of stink bugs and its evolutionary implications

The copulatory process in animals is preceded by a series of integrated communication processes which are often under selection to guarantee species-specific courtship and copula. However, individuals of species supposedly in reproductive isolation frequently copulate in nature, which has sparked the attention of evolutionary biologists for decades. While studies on this topic have strongly focused on recently diverged species or populations, few instances of heterospecific copula between distantly related species are known. Here we report an intriguing case of interspecific copula between two distantly related species of stink bugs in nature. We replicated this observation in laboratory conditions and revealed an asymmetric relation: males of Chinavia obstinata copulated with females of C. erythrocnemis but the reverse combination did not occur. We propose a series of hypotheses to explain our observations in the light of the current knowledge on mate recognition and reproductive isolation in stink bugs, considering the potential pre- and postcopulatory barriers involved. Once these two species have probably evolved in allopatry and contacted secondarily, the absence of directional selection against mating signals differentiation is a probable process. We argue that similarities in genital shape and size, most likely a result of convergent evolution, may have played a fundamental role in guaranteeing that these species achieved proper coupling.     

Filamentous bodies in human glomerulonephritis

Filamentous bodies have been identified in the glomerular cells of human kidney biopsies. These structures have a close morphological resemblance to ciliary rootlets, although the cells of the glomerular tuft only occasionally bear cilia. Their significance could be, as for cilia, of a cellular disdifferentiation of a pathological cellular proliferation.     

Identification of Megaselia scalaris (Loew, 1866) (Diptera: Phoridae) in mummified human body from Itacambira (MG), Brazil,using scanning electron microscopy and cuticular hydrocarbons

Insect puparia were found adhered to the ribs and other tissues in the abdominal cavity of a natural male mummy found in Itacambira (State of Minas Gerais, Brazil) dating to the Colonial Period. They were collected for identification by scanning electron microscopy, and for comparison of several morphological features with those described in the literature. The puparia were found open and dorsoventrally flattened, making it difficult to visualize the dorsal projections. The tegument is covered by tapered spines and contains rows of small tubercles on the dorsal and lateral regions of the puparium. The posterior spiracle consists of four parallel openings arranged in pairs. These results are indicative that the specimens belong to the species Megaselia scalaris (Loew, 1866) (Diptera: Phoridae). Additionally, cuticular hydrocarbons of the puparia were analysed by gas chromatography coupled to mass spectrometry and compared with the profile of M. scalaris reared in the laboratory.     

世界各国巨型机发展概况

以全球前500台超级计算机(TOP500)评选结果为依据，简述了世界各国巨型机的发展概况，以及我国在巨型计算机发展方面与发达国家的差距。     

生物电脑的最新进展

评述了半导体芯片计算机的致命弱点，综述了生物电脑的基本工作原理、应用前景以及最新进展。     

盲人《视唱练耳》教学探究

运用二十年来从事特殊教育本科视唱练耳教学的成功经验，把对盲人视唱练耳教学采用的、与普通高等院校音乐专业不同的教学方案，从教学课时安排、教学环节、教学实践、教学内容等方面作了认真细致的研究与总结，并对视唱练耳教学的链接与相关课程的安排作出了有意义的讨论。