Effect of heat treatment on the ATPase activity of various sarcoplasmic reticulum preparations.

Ca2+-stimulated ATPase activity of sarcoplasmic reticulum (SR) preparations is activated after a short period of preincubation at temperatures between 40 and 45 degrees C, but for temperatures higher than 48 degrees C pronounced denaturation is observed. Heat denaturation is decreased if Mg2+ or K+ are present during heat treatment.     

New findings of Hexalona-branch representatives in Brazil,with a description of Prenda gen. nov. (Crustacea: Anomopoda: Aloninae)

Altogether, Coronatella and Hexalona-branches are considered the main lineages of Aloninae – a subfamily of common bottom-dwelling microcrustaceans in freshwater environments. Although the taxonomic features of Brazilian members of the Hexalona-branch have been summarised for species from the costata-group and affinis-group, a revision of other widely distributed species in the world is still lacking in this country. The aim of this paper was to study the morphology of Brazilian populations from the guttata-group and intermedia-group, and to describe a new genus from the Hexalona-branch. The parthenogenetic females of Alona cf. guttata from Brazil have similar morphology when compared to data from the literature, but the armature of the terminal claw of its males seems to be different from those of Alona guttata sensu stricto, Alona barbulata and Alona werestschagini. The intermedia-group is formed by Alona elisae sp. nov., which seems to be endemic to the Cerrado of Brazil Central, and Alona isabellae sp. nov., which is widely distributed in Brazil; this species has a labral keel armed with 2–4 setulae, and postabdomen with setulae of lateral fascicles longer than the level of marginal denticles, morphological traits that differentiate it from Alona elisae sp. nov. Another endemic species from the Hexalona-branch is Prenda arvensis gen. nov. and sp. nov., which has two main head pores, a reduced seta on endite 1 of the first limb, sixth limb is a wide lobe. The potential of biodiversity from the Hexalona-branch from Brazil is still underestimated, and a global revision of the guttata-group and intermedia-group is very important for the progress of Aloninae taxonomy and systematics.

http://zoobank.org/urn:lsid:zoobank.org:pub:0A2E4A30-0C9C-43E8-8E72-1DEDA6AFF3C3     

Nest architecture in polydomous grass-cutting ants (Acromyrmex balzani)

Acromyrmex balzani is a grass-cutting ant species frequently found in Cerrado areas. However, little is known about the architecture of the polydomous nests of this ant. Fifteen A. balzani nests located in a cerrado region in Botucatu, São Paulo, Brazil, were studied. The polydomous nests were studied in three ways. First, we investigated the architecture in nests moulded with cement and without moulding. Second, we performed an aggressiveness test among workers in different subnests and nests. Third, we excavated the nest and collected the colony to measure the population, verifying the existence or not of a queen in all nests. A cement mould was made of seven nests to permit better visualization of internal structures such as chambers and tunnels. Eight nests were excavated without moulding and white neutral talc was used to highlight the parts of the nests. After excavation, the depth and dimensions (length, width and height) of the chambers were measured. The results showed that the nests had a single entrance hole whose structure consisted of straw and other plant residues in winter. Mounds of loose soil, if present, were found 6–48 cm from the hole. The number of chambers containing fungus ranged from one to five, with the first being found a few centimetres beneath the ground surface (4 cm) and the last up to a maximum depth of 160 cm. The length of the tunnels ranged from 12 to 28 cm. These tunnels were built in a vertical or inclined position, leading to the chambers. No waste chambers were found, with the waste being deposited externally. Additionally, the polydomous nests contained one to eight subnests. In the aggressiveness test, when concolonial workers were confronted, no aggressiveness was observed. In contrast, when allocolonial workers were confronted, there was a high incidence of aggression among them. Excavation of polydomous nests showed only one queen for each polydomous nest, i.e. subnests with a single queen. Our study contributes to a better understanding of the so far unknown nest architecture of the polydomous grass-cutting ant A. balzani.     

Can We Predict the Financial Markets Based on Google's Search Queries?

We look into the interaction of Google's search queries and several aspects of international equity markets. Using a novel methodology for selecting words and a vector autoregressive modeling approach, we study whether the search queries of finance‐related words can have an impact on returns, volatility of returns and traded volume in four different English‐speaking countries. We identify several words whose search frequency is associated with changes in the dependent variables. In particular, we find that increases in search queries including the word stock predict increased volatility and decreased index returns over the next week. On top of that, we investigate the performance of a market‐timing strategy based on the search frequency of this word and benchmark it against random words from the Word‐Net database and a naive buy‐and‐hold strategy. The results of this empirical application are positive and particularly stronger during the global crisis of 2009. Copyright © 2016 John Wiley & Sons, Ltd.     

Action of some compounds on the adenosine triphosphate pool ofStreptococcus faecalis

Résumé Les auteurs étudient le contenu en ATP chez leStreptococcus faecalis, après l'addition de glucose et en présence de diverses substances. Les effets les plus évidents ont été ceux du dicumarol augmentant la valeur de la constante d'entrée et la quantité de l'ATP; du 2,4-dinitrophénol augmentant les 2 constantes (d'entrée et de décomposition); de l'arsénate réduisant la quantité de l'ATP; de l'azide augmentant la constante de décomposition; et de Ja gramicidine qui augmente non seulement la constante de décomposition mais réduit aussi la quantité de l'ATP dans le «pool».     

Vesicles carrying nuclear material in matureCyprinus carpio erythrocytes

Zusammenfassung Chromatinhaltige feulgenpositive Bläschen wurden im Cytoplasma der Erythrocyten vonCyprinus carpio gefunden. Sie haben ihren Ursprung in den unmittelbar an der Kernmembran anliegenden Mitochondrien, die während der Chromatinaufnahme allmählich ihre Struktur verlieren.

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The authors wish to thank Mrs.Vera Mondin Weisz and Mr.C. A. Gonçalves Silva for their technical assistance and Mrs.Sibylle Heller for her editorial aid and translation. This research has been supported by the Conselho Nacional de Pesquisas (Proc. No. 10112/71) and Fundo Especial de Despesas do Instituto Butantan.     

Effect of high anodic polarization on the passive layer properties of superduplex stainless steel friction stir welds at different chloride electrolyte pH values and temperatures

The conditions used for friction stir welding of duplex stainless steels determine the resulting mechanical and corrosion performance of the material.This study investigates the corrosion resistance of UNS S32750 and S32760 superduplex stainless steels(SDSSs)joined by friction stir welding,employing cyclic polarization,Mott–Schottky,and microscopy techniques for analysis.The microscopy images indicated the presence of a deleterious intermetallic phase after electrolytic etching of S32760,as well as decreased corrosion resistance.The presence of molybdenum in the steels promoted better passive behavior at low pH.The Mott–Schottky curves revealed p-n heterojunction behavior of the passive oxide.Images acquired after the polarization test by scanning electron microscopy showed higher passivation propensity with increases of temperature and pH.