114 research outputs found
Nesting Biology and Fungiculture of the Fungus-Growing Ant, Mycetagroicus cerradensis: New Light on the Origin of Higher Attine Agriculture
The genus Mycetagroicus is perhaps the least known of all fungus-growing ant genera, having been first described in 2001 from museum specimens. A recent molecular phylogenetic analysis of the fungus-growing ants demonstrated that Mycetagroicus is the sister to all higher attine ants (Trachymyrmex, Sericomyrmex, Acromyrmex, Pseudoatta, and Atta), making it of extreme importance for understanding the transition between lower and higher attine agriculture. Four nests of Mycetagroicus cerradensis near Uberlândia, Minas Gerais, Brazil were excavated, and fungus chambers for one were located at a depth of 3.5 meters. Based on its lack of gongylidia (hyphal-tip swellings typical of higher attine cultivars), and a phylogenetic analysis of the ITS rDNA gene region, M. cerradensis cultivates a lower attine fungus in Clade 2 of lower attine (G3) fungi. This finding refines a previous estimate for the origin of higher attine agriculture, an event that can now be dated at approximately 21–25 mya in the ancestor of extant species of Trachymyrmex and Sericomyrmex
Studies of Zγ production in association with a high-mass dijet system in pp collisions at √s=8 TeV with the ATLAS detector
The production of a Z boson and a photon in association with a high-mass dijet system is studied using 20.2 fb −1 of proton-proton collision data at a centre-of-mass energy of s=8 TeV recorded with the ATLAS detector in 2012 at the Large Hadron Collider. Final states with a photon and a Z boson decaying into a pair of either electrons, muons, or neutrinos are analysed. Electroweak and total pp → Zγjj cross-sections are extracted in two fiducial regions with different sensitivities to electroweak production processes. Quartic couplings of vector bosons are studied in regions of phase space with an enhanced contribution from pure electroweak production, sensitive to vector-boson scattering processes VV → Zγ. No deviations from Standard Model predictions are observed and constraints are placed on anomalous couplings parameterized by higher-dimensional operators using effective field theory.[Figure not available: see fulltext.]
Evidence for a Novel Marine Harmful Algal Bloom: Cyanotoxin (Microcystin) Transfer from Land to Sea Otters
“Super-blooms” of cyanobacteria that produce potent and environmentally persistent biotoxins (microcystins) are an emerging global health issue in freshwater habitats. Monitoring of the marine environment for secondary impacts has been minimal, although microcystin-contaminated freshwater is known to be entering marine ecosystems. Here we confirm deaths of marine mammals from microcystin intoxication and provide evidence implicating land-sea flow with trophic transfer through marine invertebrates as the most likely route of exposure. This hypothesis was evaluated through environmental detection of potential freshwater and marine microcystin sources, sea otter necropsy with biochemical analysis of tissues and evaluation of bioaccumulation of freshwater microcystins by marine invertebrates. Ocean discharge of freshwater microcystins was confirmed for three nutrient-impaired rivers flowing into the Monterey Bay National Marine Sanctuary, and microcystin concentrations up to 2,900 ppm (2.9 million ppb) were detected in a freshwater lake and downstream tributaries to within 1 km of the ocean. Deaths of 21 southern sea otters, a federally listed threatened species, were linked to microcystin intoxication. Finally, farmed and free-living marine clams, mussels and oysters of species that are often consumed by sea otters and humans exhibited significant biomagnification (to 107 times ambient water levels) and slow depuration of freshwater cyanotoxins, suggesting a potentially serious environmental and public health threat that extends from the lowest trophic levels of nutrient-impaired freshwater habitat to apex marine predators. Microcystin-poisoned sea otters were commonly recovered near river mouths and harbors and contaminated marine bivalves were implicated as the most likely source of this potent hepatotoxin for wild otters. This is the first report of deaths of marine mammals due to cyanotoxins and confirms the existence of a novel class of marine “harmful algal bloom” in the Pacific coastal environment; that of hepatotoxic shellfish poisoning (HSP), suggesting that animals and humans are at risk from microcystin poisoning when consuming shellfish harvested at the land-sea interface
Association between shift work, salivary cortisol levels, stress and fatigue in nurses: integrative review
A malacological survey in the Manso Power Plant, State of Mato Grosso, Brazil: new records of freshwater snails, including transmitters of schistosomiasis and exotic species
Introduction: Schistosomiasis is a parasitic disease of public health concern in Brazil, and the construction of hydroelectric
dams, in addition to increasing permanent human settlement and tourism, has created conditions suitable for the establishment of
mollusks that can transmit schistosomiasis. Such areas require a number of actions to prevent the establishment of schistosomiasis.
This paper reports on a freshwater malacological survey carried out in the geographical area of the Manso Power Plant.
Methods: Mollusks were collected in 18 municipalities in the State of Mato Grosso between February 2002 and February
2004 (qualitative study) and from April 2009 to February 2011 (quantitative study). Results: Thirty-one species of mollusks
were collected, including newly recorded species (Antillorbis nordestensis and Burnupia ingae). In addition, the geographic
distributions of known species, including Biomphalaria straminea, a snail vector of Schistosoma mansoni, were expanded.
A total of 4,507 specimens were collected in the APM Manso reservoir (Usina Hidrelétrica de Aproveitamento Múltiplo de
Manso) during the quantitative study, and Biomphalaria amazonica was found in six of the 10 localities analyzed. The Afroasiatic
species Melanoides tuberculata, introduced after February 2009, was the dominant species (relative abundance 94.96%).
Conclusions: The study area is epidemiologically important due to the occurrence of B. straminea and B. amazonica, which are
vectors of schistosomiasis, and M. tuberculata, a snail host of Centrocestus formosanus, which is responsible for centrocestiasis
transmission. Observations of M. tuberculata and the exotic freshwater clams Corbicula fluminea and Corbicula largillierti raise
concerns about biodiversity
Evaluation of interventions on road traffic injuries in Peru: a qualitative approach
<p>Abstract</p> <p>Background</p> <p>Evaluation of interventions on road traffic injuries (RTI) going beyond the assessment of impact to include factors underlying success or failure is an important complement to standard impact evaluations. We report here how we used a qualitative approach to assess current interventions implemented to reduce RTIs in Peru.</p> <p>Methods</p> <p>We performed in-depth interviews with policymakers and technical officers involved in the implementation of RTI interventions to get their insight on design, implementation and evaluation aspects. We then conducted a workshop with key stakeholders to analyze the results of in-depth interviews, and to further discuss and identify key programmatic considerations when designing and implementing RTI interventions. We finally performed brainstorming sessions to assess potential system-wide effects of a selected intervention (Zero Tolerance), and to identify adaptation and redesign needs for this intervention.</p> <p>Results</p> <p>Key programmatic components were consistently identified that should be considered when designing and implementing RTI interventions. They include effective and sustained political commitment and planning; sufficient and sustained budget allocation; training, supervision, monitoring and evaluation of implemented policies; multisectoral participation; and strong governance and accountability. Brainstorming sessions revealed major negative effects of the selected intervention on various system building blocks.</p> <p>Conclusions</p> <p>Our approach revealed substantial caveats in current RTI interventions in Peru, and fundamental negative effects on several components of the sectors and systems involved. It also highlighted programmatic issues that should be applied to guarantee an effective implementation and evaluation of these policies. The findings from this study were discussed with key stakeholders for consideration in further designing and planning RTI control interventions in Peru.</p
Isolating the effects of precipitation, soil conditions, and litter quality on leaf litter decomposition in lowland tropical forests
ORIGEM, RAMIFICAÇÃO E DISTRIBUIÇÃO DA ARTÉRIA CELÍACA EM CANÁRIOS-DA-TERRA (Sicalis flaveola)
Proposta de um modelo de avaliação da atenção pública à saúde bucal da criança
O objetivo deste estudo foi propor um modelo para a avaliação da qualidade da atenção à saúde bucal da criança. O marco conceitual para a elaboração da matriz avaliativa foi composto por estudos de avaliação de serviços de atenção à saúde bucal no Brasil e em outros países, e levantamento e revisão das políticas públicas vigentes relacionadas à saúde da criança no Brasil. A qualidade da gestão municipal na atenção básica da saúde bucal infantil foi avaliada sob duas dimensões: Gestão e Provimento. Na primeira, foram dispostas duas subdimensões: articulação e recursos, e na segunda, mais duas subdimensões: promoção e prevenção, e diagnóstico e tratamento. A matriz de avaliação ficou composta por nove indicadores na dimensão de Gestão e nove na dimensão de Provimento. Os indicadores foram elaborados em oficinas com especialistas. O modelo tem condições de ser aplicado em municípios com diferentes portes populacionais, e permite identificar os pontos nos quais os gestores devem aperfeiçoar suas ações
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