Miniature standoff Raman probe for neurosurgical applications

Removal of intrinsic brain tumors is a delicate process, where a high degree of specificity is required to remove all of the tumor tissue without damaging healthy brain. The accuracy of this process can be greatly enhanced by intraoperative guidance. Optical biopsies using Raman spectroscopy are a minimally invasive and lower-cost alternative to current guidance methods. A miniature Raman probe for performing optical biopsies of human brain tissue is presented. The probe allows sampling inside a conventional stereotactic brain biopsy system: a needle of length 200 mm and inner diameter of 1.8 mm. By employing a miniature stand-off Raman design, the probe removes the need for any additional components to be inserted into the brain. Additionally, the probe achieves a very low internal silica background while maintaining good collection of Raman signal. To illustrate this, the probe is compared with a Raman probe that uses a pair of optical fibers for collection. The miniature stand-off Raman probe is shown to collect a comparable number of Raman scattered photons, but the Raman signal to background ratio is improved by a factor of five at Raman shifts below ∼500  cm−1. The probe’s suitability for use on tissue is demonstrated by discriminating between different types of healthy porcine brain tissue

Culicidae (diptera: Culicomorpha) from the central brazilian amazon: Nhamundá and abacaxis rivers

Mosquito fauna (Culicidae) from remote areas along the geographical limits of the State of Amazonas were assessed by employing CDC, Shannon, Malaise and Suspended traps, together with net sweeping and immature collections. Two hundred and six collections were performed in seven localities along the Nhamundá and Abacaxis Rivers, State of Amazonas, Brazil, during May and June 2008. The northernmost locality was 120 km from Nhamundá, whereas the southernmost locality was 150 km from the mouth of the Abacaxis River. The 5,290 mosquitoes collected are distributed in 16 genera, representing 109 different species, of which eight are new distributional records for the State of Amazonas. Furthermore, there are nine morphospecies which may represent undescribed new taxa, five of which are also new records for the State of Amazonas. Culex presented the highest number of species and the largest number of individuals. Anopheles, which represents 3% of the total sample, had the second highest number of species, followed by Wyeomyia. Psorophora and Aedes, represent the third and fourth largest number of individuals. The most abundant species was Cx. (Mel.) vaxus Dyar, 1920 followed by Cx. (Mel.) eknomios Forattini & Sallum, 1992, Cx. (Cux.) mollis Dyar & Knab, 1906, Cx. (Mel.) theobaldi Lutz, 1904, and Cx. (Cux.) declarator Dyar & Knab, 1906. The epidemiological and ecological implications of mosquito species found are discussed and are compared with other mosquito inventories from the Amazon region. The results presented represent the largest standardized inventory of mosquitoes of the Nhamundá and Abacaxis rivers, with the identification of 118 species level taxa distributed in seven localities, within four municipalities (Nhamundá, Maués, Borba, Nova Olinda do Norte), of which we have only few or no records in the published literature. © 2013 Sociedade Brasileira de Zoologia

CFD study of Jet Impingement Test erosion using Ansys Fluent® and OpenFOAM®

The initial aim of this study was to compare OpenFoam and Ansys Fluent in order to verify OpenFoam’s Lagrangian Library and erosion capabilities. However, it was found that previous versions of Fluent have been providing wrong results for the discrete phase and the differences with the latest version (Ansys Fluent 15) are shown. A Submerged Jet Impingement Test is an effective method for studying erosion created by solid particles entrained in a liquid. When considering low particle concentrations a Lagrangian modeling of the particulate phase is a reasonable approach. Proper linkage between OpenFOAM’s Lagrangian library and the solver pimpleFoam for incompressible transient flows allows two-phase simulations to be undertaken for comparison with Ansys Fluent with the aim of verifying OpenFoam’s accuracy. Steady state convergence for the fluid flow is first accomplished and the results are compared, confirming a good agreement between the two packages. A transient simulation was then set up and spherical particles incorporated into the fluid flow. An assessment of the two codes’ discrete phase models was carried out, focusing on the differences between impact angles and velocities yielded at the impingement plate’s surface employing a similar strategy to that outlined first by Hattori et al. (2008) and later by Gnanavelu et al. (2009, 2011). In the comparison of OpenFoam with the latest version of Fluent, the main differences between the injection models are highlighted and the coupling possibilities between phases are taken into consideration. Agreement between trends for both impact angles and velocities is satisfactory when the last version of the commercial package is considered and the average discrepancy between numerical values is very low, verifying OpenFoam’s Lagrangian library. Two different Jet Impingement Test configurations are also compared and the differences highlighted

Acervo de mosquitos (Diptera, Culicidae) de Nelson L. Cerqueira na Coleção de Invertebrados do Instituto Nacional de Pesquisas da Amazônia, Manaus, Brasil

The Nelson L. Cerqueira Mosquito Collection (Diptera, Culicidae) in the Invertebrate Collection of the Instituto Nacional de Pesquisas da Amazonia, Manaus, Brazil. The discovery of mosquito specimens that belonged to Nelson L. Cerqueira, which are being deposited in the Instituto Nacional de Pesquisas da Amazonia Invertebrate Collection, is reported. The collection contains 2,046 adult specimens and 387 slide preparations representing 261 species, 22 genera, including 51 paratypes of 34 species. More than 90% of the specimens were collected in Brazil of which half are from the State of Amazonas. A list of the species represented in this collection is provided indicating the number of specimens for each type of preparation and the collecting localities. The type specimens are also listed including their label data and other pertinent information