A mucous secretion in the malpighian tubes of a neotropical bumblebee,Bombus atratus Franklin

Summary A filamentous secretion composed of carboxylated and sulfated acid glycosaminoglycans (AGAG), neutral polysaccharides, and protein(s) appears in the lumen of the Malpighian tubes of the fully grown larvae of the bumblebee,Bombus atratus Franklin. A well-ordered macromolecular array was demonstrated specially for the carboxylated AGAG components of this secretion, based on their linear dichroism and birefringence properties. It is suggested that the carboxylated AGAG macromolecules can acquire a helical conformation when present at the lumen of the organ. The mucous secretion elaborated by the Malpighian tubes ofB. atratus is excreted from the larvae in the form of condensed filaments. Its function remains unclear. Globules with concentric lamination containing protein and neutral polysaccharides were seen detaching from the apical border of the epithelial cells of the Malpighian tubes of the fully grown larvae. It could not be established whether they contribute for the elaboration of the filamentous secretion. Morphologically similar globules have been assumed in some other insect groups to originate from cytolysomes. Urate crystals surrounded by a halo of calcium granules were also found in the lumen of the Malpighian tubes ofB. atratus.     

Four new species of <Emphasis Type="Italic">Justicia</Emphasis> (Acanthaceae) from the Caatinga biome of Bahia,Brazil

A survey of the tribe Justicieae from the Caatinga biome, in the State of Bahia, revealed the following four new species of Justicia (Acanthaceae): J. angustissima, J. attenuata, J. chlamidocalyx and J. jacuipensis. J. attenuata and J. jacuipensis are known only from the types; the latter is considered Critically Endangered (CR) because the area where it was collected has been flooded since the construction of the Pedra do Cavalo dam and the region around this area has been extensively disturbed. J. angustissima and J. chlamidocalyx were found in six locations. They have a wide distribution in Central Bahia and the conservation status of both species should be classified as Least Concern (LC). The four species are described and illustrations and comments are provided.     

Life cycle inventory and impact assessment for an asphalt pavement road construction—a case study in Brazil

The International Journal of Life Cycle Assessment - Currently, there are no life cycle impact data available on the construction of road infrastructure in Brazil. This study aimed to determine...     

Electrified bioreactors: the next power-up for biometallurgical wastewater treatment

Over the past decades, biological treatment of metallurgical wastewaters has become commonplace. Passive systems require intensive land use due to their slow treatment rates, do not recover embedded resources and are poorly controllable. Active systems however require the addition of chemicals, increasing operational costs and possibly negatively affecting safety and the environment. Electrification of biological systems can reduce the use of chemicals, operational costs, surface footprint and environmental impact when compared to passive and active technologies whilst increasing the recovery of resources and the extraction of products. Electrification of low rate applications has resulted in the development of bioelectrochemical systems (BES), but electrification of high rate systems has been lagging behind due to the limited mass transfer, electron transfer and biomass density in BES. We postulate that for high rate applications, the electrification of bioreactors, for example, through the use of electrolyzers, may herald a new generation of electrified biological systems (EBS). In this review, we evaluate the latest trends in the field of biometallurgical and microbial-electrochemical wastewater treatment and discuss the advantages and challenges of these existing treatment technologies. We advocate for future research to focus on the development of electrified bioreactors, exploring the boundaries and limitations of these systems, and their validity upon treating industrial wastewaters.     

Change with age of feulgen-DNA values in the blood-sucking insect,Triatoma infestans klug

Summary Feulgen-DNA values were evaluated cytophotometrically in the Malpighian tubes of T. infestans at the nymphal, adult and ageing life periods. In all cases the total nuclear Feulgen-DNA contents were found to be distributed within the 32C and 64C classes. However, part of the Feulgen-DNA values is shifted to lower intervals in ageing insects, as compared with nymphal and adult individuals, promoted by decrease in Feulgen-DNA values of the euchromatins. Changed response to Feulgen reaction due to some aging-induced alteration in DNP complexes, and/or breaks and loss of DNA in the euchromatins, as part of the senescence process, are ascribed to be responsible for such phenomenon.     

Hyperepilithics—An overlooked life form of vascular plants on tropical vertical rock walls

Vascular epiphytes are a characteristic life form in many tropical regions and often occur growing on bare rocks. South America has the highest diversity. Here, we describe a neglected life form: hyperepilithics adapted and restricted to growing on vertical (inclination above 70°) and bare rock walls without having roots intruding the substrate. Hyperepilithics are in particular present on Brazilian inselbergs and dominated by highly specialized Bromeliaceae, mainly of the genera Stigmatodon, Tillandsia and Alcantarea, whereas Orchidaceae surprisingly has a low representation. An overview of this habitat, the life form hyperepilithics and a comparison with similar paleotropical habitats (mainly inselbergs in Western/Eastern Africa and India) are provided. Attention is drawn to hyperepilithics as a most promising and not yet exploited source for a sustainable urban ‘vertical gardening’, for example in tropical megacities.