Insights Into the Feeding Behaviors and Biomechanics of \u3ci\u3eVarroa destructor\u3c/i\u3e Mites on Honey Bee Pupae Using Electropenetrography and Histology

Feeding behaviors and biomechanics of female Varroa destructor mites are revealed from AC-DC electropenetrography (EPG) recordings of mites feeding from Apis mellifera honey bee pupae and histology of mite internal ingestion apparatus. EPG signals characteristic of arthropod suction feeding (ingestion) were identified for mites that fed on pupae during overnight recordings. Ingestion by these mites was confirmed afterwards by observing internally fluorescent microbeads previously injected into their hosts. Micrographs of internal ingestion apparatus illustrate the connection between a gnathosomal tube and a pharyngeal lumen, which is surrounded by alternating dilator and constrictor muscles. Inspection of EPG signals showed the muscularized mite pharyngeal pump operates at a mean repetition rate of 4.5 cycles/s to ingest host fluids. Separate feeding events observed for mites numbered between 23 and 33 over approximately 16 h of recording, with each event lasting ~10 s. Feeding events were each separated by ~2 min. Consecutive feeding events separated by either locomotion or prolonged periods of quiescence were grouped into feeding bouts, which ranged in number from one to six. Statistical analyses of EPG data revealed that feeding events were prolonged for mites having lower pharyngeal pump frequencies, and mites having prolonged feeding events went unfed for significantly more time between feeding events. These results suggest that mites may adjust behaviors to meet limitations of their feeding apparatus to acquire similar amounts of food. Data reported here help to provide a more robust view of Varroa mite feeding than those previously reported and are both reminiscent of, as well as distinct from, some other acarines and fluid-feeding insects

Distribution of the daily Sunspot Number variation for the last 14 solar cycles

The difference between consecutive daily Sunspot Numbers was analysed. Its distribution was approximated on a large time scale with an exponential law. In order to verify this approximation a Maximum Entropy distribution was generated by a modified version of the Simulated Annealing algorithm. The exponential approximation holds for the generated distribution too. The exponential law is characteristic for time scales covering whole cycles and it is mostly a characteristic of the Sunspot Number fluctuations and not of its average variation.Comment: Accepted for publication in Solar Physic

A transformação da educação em mercadoria no Brasil The transformation of education into commodity in Brazil

O presente artigo apresenta pesquisa que estuda as consequências perceptíveis do processo de penetração dos fundos financeiros na educação superior no Brasil e, posteriormente, a emissão de ações de instituições de ensino diretamente na bolsa de valores. Entre os resultados observados encontra-se o rápido crescimento das instituições que adotaram tal estratégia. A forma mais visível desse crescimento é a compra de outras instituições e seu aperfeiçoamento, por meio da implantação de uma gestão mais profissionalizada. Tal processo tem propiciado o crescimento acelerado de algumas instituições, generalizando a educação como uma mercadoria, assim como a tendencial oligopolização da oferta. Conclui-se afirmando que é cabível falar-se em uma financeirização da educação, posto que é o setor financeiro que assume a hegemonia na educação privada no país.<br>This paper presents a research on the noticeable consequences of the supply of private equities and venture capital in Brazilian Higher Education and of the subsequent going public of many teaching institutions. These are growing fast, mainly through the purchase of other schools, whose administration is professionalized. Such process has generalized both education as a commodity and the oligopolization of provision. It is thus possible to conclude that education has been financialized, since private education is nowadays hegemonic in Brazil