Probing neutrino oscillations in supersymmetric models at the Large Hadron Collider

The lightest supersymmetric particle may decay with branching ratios that correlate with neutrino oscillation parameters. In this case the CERN Large Hadron Collider (LHC) has the potential to probe the atmospheric neutrino mixing angle with sensitivity competitive to its low-energy determination by underground experiments. Under realistic detection assumptions, we identify the necessary conditions for the experiments at CERN's LHC to probe the simplest scenario for neutrino masses induced by minimal supergravity with bilinear R parity violation.

Chemical analyses confirm a rare case of seed dispersal by bees

It has been suggested that dispersal of seeds of Coussapoa asperifolia magnifolia could have endozoochoric dispersal by frugivorous birds and monkeys because the fruits are red when ripe, or exozoochoric dispersal, because the exocarp is mucilaginous and sticky. However, our field observations showed only stingless bees collecting the exocarp with seeds of C. asperifolia magnifolia, which are used for building and repairing their nests, from which the plants sprout. This paper aimed to determine the fruit chemical composition, since we postulated that C. asperifolia magnifolia is neither consumed by birds nor monkeys due to being very sticky and apparently resinous. Apolar extract analyses revealed the fruits are not resinous but extremely rich in waxes ( mainly esterified triglycerides), and polar extract analyses revealed the sugar content to be close to the sensorial minimum level. This probably accounts for why only stingless bees are seen visiting fruits and dispersing seeds.

Description of the Immatures of Workers of the Weaver Ant, Camponotus textor (Hymenoptera: Formicidae)

The weaver ants Camponotus textor (Forel) (Hymenoptera: Formicidae) are native to Central and South America, where they use their larvae to build silken nests by sewing tree leaves together. Few Studies have been conducted with this species, and little is known about the morphology of their larvae. Tie present paper estimated the number of larval instars of C. textor and presents a detailed morphological description of each immature stage based on light and electron microscopic observations. The number of larval in stars was estimated as four based oil the frequency distribution of larval head widths. Tic larvae of this species presented some typical characteristics of Camponotus (Mayr) larvae: body shape `pogonomyrmecoid`, ten pairs of spiracles, antennae with three sensilla, conspicuous `chiloscleres` on the labrum, and mature larvae with pronounced labial pseudopalps. Unprecedented characteristics would include: great diversity of body hair types, and `camponotoid` mandibles but with four medial denticles. This information can aid biological and taxonomic studies with these ants, and may be useful for ant systematics.

Pycnoscelus surinamensis (Linnaeus, 1758) (Blaberoidea: Blaberidae), a cockroach with a possible association with the ant Brachymyrmex cordemoyi Forel, 1895 (Hymenoptera: Formicidae) and which may be exhibiting a domiciliation trend.

In the present paper, we report on the occurrence of the cockroach Pycnoscelus surinamensis (Linnaeus, 1758) in Brachymyrmex cordemoyi Forel, 1895 nests, indicating a possible symbiosis between these two species. Also, the finding of intradomicile P. surinamensis nymphs may indicate this species is extending its habitat to human habitations, i.e. changing its ecological category from peridomestic to domestic.

Intraspecific queen parasitism in a highly eusocial bee

Insect societies are well-known for their advanced cooperation, but their colonies are also vulnerable to reproductive parasitism. Here, we present a novel example of an intra-specific social parasitism in a highly eusocial bee, the stingless bee Melipona scutellaris. In particular, we provide genetic evidence which shows that, upon loss of the mother queen, many colonies are invaded by unrelated queens that fly in from unrelated hives nearby. The reasons for the occurrence of this surprising form of social parasitism may be linked to the fact that unlike honeybees, Melipona bees produce new queens in great excess of colony needs, and that this exerts much greater selection on queens to seek alternative reproductive options, such as by taking over other nests. Overall, our results are the first to demonstrate that queens in highly eusocial bees can found colonies not only via supersedure or swarming, but also by infiltrating and taking over other unrelated nests.

Determination of in situ uniaxial compressive strength of coal seams based on geophysical data

The central issue for pillar design in underground coal mining is the in situ uniaxial compressive strength (sigma (cm)). The paper proposes a new method for estimating in situ uniaxial compressive strength in coal seams based on laboratory strength and P wave propagation velocity. It describes the collection of samples in the Bonito coal seam, Fontanella Mine, southern Brazil, the techniques used for the structural mapping of the coal seam and determination of seismic wave propagation velocity as well as the laboratory procedures used to determine the strength and ultrasonic wave velocity. The results obtained using the new methodology are compared with those from seven other techniques for estimating in situ rock mass uniaxial compressive strength.

Artificial neural networks analysis of Sao Paulo subway tunnel settlement data

Artificial neural networks have been used to analyze a number of engineering problems, including settlement caused by different tunneling methods in various types of ground mass. This paper focuses on settlement over shotcrete- supported tunnels on Sao Paulo subway line 2 (West Extension) that were excavated in Tertiary sediments using the sequential excavation method. The adjusted network is a good tool for predicting settlement above new tunnels to be excavated in similar conditions. The influence of network training parameters on the quality of results is also discussed. (C) 2007 Elsevier Ltd. All rights reserved.

Substratum choice for nesting in male Nile tilapia Oreochromis niloticus

Four substrata were offered to groups of adult Nile tilapia Oreochromis niloticus (one male and two females) simultaneously: pure sand, a mixture of sand and shells, stones and no substratum. The results showed that males chose to dig nests in a lighter and more homogeneous substratum.

Increased expression of fructan 1-exohydrolase in rhizophores of Vernonia herbacea during sprouting and exposure to low temperature

Rhizophores of Vernonia herbacea, an Asteraceae found in the Brazilian Cerrado, store high amounts of fructans that vary in composition over the phenological cycle. Fructan 1-exohydrolase (1-FEH) activity is detectable during the sprouting phase, mainly in the proximal regions of rhizophores, of plants induced to sprout by defoliation and/or cold storage. We found an increase in 1-FEH gene expression during natural and induced sprouting and further enhancement through low-temperature treatment. Furthermore, a comparative analysis of 1-FEH gene expression in different regions of the rhizophores during the transition from dormancy to sprouting is presented. Transcripts were detected mainly in the proximal region, coinciding with high 1-FEH activity and a high concentration of free fructose. Low temperature promoted the accumulation of fructans of a low degree of polymerization (DP) and enhanced 1-FEH activity and gene expression. It is hypothesized that a set of 1-FEH proteins acts in two different ways during fructan mobilization: (1) by hydrolyzing fructo-oligosaccharides and -polysaccharides in sprouting plants (naturally or induced) for carbon supply and (2) by hydrolyzing preferably fructo-polysaccharides under low temperature to maintain the oligosaccharide pool for plant cold acclimation. (C) 2010 Elsevier GmbH. All rights reserved.

Cloning, characterization and functional analysis of a 1-FEH cDNA from Vernonia herbacea (Vell.) Rusby

Variations in the inulin contents have been detected in rhizophores of Vernonia herbacea during the phenological cycle. These variations indicate the occurrence of active inulin synthesis and depolymerization throughout the cycle and a role for this carbohydrate as a reserve compound. 1-Fructan exohydrolase (1-FEH) is the enzyme responsible for inulin depolymerization, and its activity has been detected in rhizophores of sprouting plants. Defoliation and low temperature are enhancer conditions of this 1-FEH activity. The aim of the present work was the cloning of this enzyme. Rhizophores were collected from plants induced to sprout, followed by storage at 5C. A full length 1-FEH cDNA sequence was obtained by PCR and inverse PCR techniques, and expressed in Pichia pastoris. Cold storage enhances FEH gene expression. Vh1-FEH was shown to be a functional 1-FEH, hydrolyzing predominantly -2,1 linkages, sharing high identity with chicory FEH sequences, and its activity was inhibited by 81 in the presence of 10 mM sucrose. In V. herbacea, low temperature and sucrose play a role in the control of fructan degradation. This is the first study concerning the cloning and functional analysis of a 1-FEH cDNA of a native species from the Brazilian Cerrado. Results will contribute to understanding the role of fructans in the establishment of a very successful fructan flora of the Brazilian Cerrado, subjected to water limitation and low temperature during winter.

Trypanosoma cruzi: The effects of zinc supplementation in the immune response during the course of experimental disease

Zinc is an essential nutritional component required for normal development and maintenance of immune functions. The possible effects of zinc in upregulating the host immune response during the acute and chronic phases of experimental Chagas` disease were evaluated. In young, infected and Zn-supplemented animals, higher concentrations of IFN-gamma and NO were observed. During the chronic phase, decreased concentrations of NO and IFN-gamma were found for older infected animals that received Zn supplementation. For young animals, hearts from Zn-supplemented groups displayed reduced inflammatory infiltrate, heart weight and number of amastigote burdens. For older, infected and Zn-supplemented animals amastigote nests were absent with reduced inflammatory cell infiltrate. This study identifies a potentially novel therapeutic approach that could control the parasite load during acute phase of disease, consequently preventing the deleterious, parasite-elicited responses observed during chronic phase. (C) 2008 Elsevier Inc. All rights reserved.

Histopathological Changes in the Placentas and Fetuses of Mice Infected with Trypanosoma cruzi Isolated from the Myotis nigricans nigricans Bat

Histopathological changes and placental transmission were studied in the late stages of pregnancy in mice infected with a strain of Trypanosoma cruzi, isolated from a Myolis nigricans nigricans bat. Large amastigote nests were observed in uterine muscles, as well as in decidual and endothelial placental cells. In addition, persistent coagulative and fibrotic Vascular degeneration was observed. Large amastigote burdens were found in giant cells, spongioblasts and endothelial cells within the labyrinthine layer. Transplacental transmission was confirmed in 30% of the fetuses examined, in which amastrigote nests were seen only in striated muscle. During tire acute phase, intrauterine development was impaired as the result of parasitic invasion of the placenta, and fetal mortality rose to 10%. (C) 2008 Elsevier Ltd. All rights reserved.

Economic , Educational and Conservation Benefits of Sea Turtle Based Ecotourism: A Study Focused on Mon Repos

The study examines the economic, educational and conservation values of sea turtle-based ecotourism in Australia. The centre-piece of this research is a case study undertaken at the Mon Repos Conservation Park located near the town of Bundaberg, Queensland. Each year from mid-November to end of March, thousands of visitors visit Mon Repos Conservation Park to view sea turtles either nesting on the one km stretch of beach or to see hatchlings emerge from their nests and march on to the sea or both. As a result of this activity there are considerable economic benefits to the Bundaberg region during the sea turtle season. The study examines the economic impact of sea turtle viewing at Mon Repos to the region. The study assesses the recreational value of sea turtle viewing. Furthermore, sea turtle-based ecotourism also provides educational and conservation benefits that are important for the protection and conservation of sea turtles, especially in Australia. The study specifies the extent of the educational impact and conservation appreciation of sea turtle viewing at Mon Repos Conservation Park. As a background to the study, Mon Repos visitors’ profile and socio-economic data of visitors are provided. In order to conduct this study, 1,200 survey forms were distributed, out of which 519 usable responses were obtained.

Nest temperature and respiratory gases during natural incubation in the broad-shelled river turtle, Chelodina expansa (Testudinata : Chelidae)

Temperature was monitored in three natural nests, and oxygen and carbon dioxide partial pressure monitored in one natural nest of the broad-shelled river turtle, Chelodina expansa, throughout incubation. Nest temperature decreased after nest construction in autumn, remained low during winter and gradually increased in spring to a maximum in summer. In a nest where temperature was recorded every hour, temperature typically fluctuated through a 2 degrees C cycle on a daily basis throughout the entire incubation period, and the nest always heated faster than it cooled. Oxygen and carbon dioxide partial pressures in this nest were similar to soil oxygen and carbon dioxide partial pressures for the first 5 months of incubation, but nest respiratory gas tensions deviated from the surrounding soil over the last three months of incubation. Nest respiratory gas tensions were not greatly different from those in the atmosphere above the ground except after periods of rain. After heavy rain during the last 3 months of incubation the nest became moderately hypoxic (P-O2 similar to 100 Torr) and hypercapnic (P-CO2 similar to 50 Torr) for several successive days. These short periods of hypoxia and hypercapnia were not lethal.

Bird responses at inherent and induced edges in the Murray Mallee, South Australia. 2. Nest predation as an edge effect

We assayed nest predation as an edge effect, using artificial ground nests, at inherent (naturally occurring) and induced (human-created) edges, in the Murray Mallee, South Australia. Nests were constructed at distances between 0-120 m away from habitat edges. The relative predation rate on nests generally increased close to induced edges with a significant difference (P < 0.05) recorded for two out of five experiments. Predation rate at inherent edges was similar from the edge to the interior, and was lower than that recorded at induced edges. Our results suggest that increased predator numbers, activity or efficiency at locating nests occurred close to the induced edges at our study sites.