FDG-PET Quantification of Lung Inflammation with Image-Derived Blood Input Function in Mice

Dynamic FDG-PET imaging was used to study inflammation in lungs of mice following administration of a virulent strain of Klebsiella (K.) pneumoniae. Net whole-lung FDG influx constant (Ki) was determined in a compartment model using an image-derived blood input function. Methods. K. pneumoniae (~3 x 105 CFU) was intratracheally administered to six mice with 6 other mice serving as controls. Dynamic FDG-PET and X-Ray CT scans were acquired 24 hr after K. pneumoniae administration. The experimental lung time activity curves were fitted to a 3-compartment FDG model to obtain Ki. Following imaging, lungs were excised and immunohistochemistry analysis was done to assess the relative presence of neutrophils and macrophages. Results. Mean Ki for control and K. pneumoniae infected mice were (5.1 ± 1.2) ×10−3 versus (11.4 ± 2.0) ×10−3 min−1, respectively, revealing a 2.24 fold significant increase (P = 0.0003) in the rate of FDG uptake in the infected lung. Immunohistochemistry revealed that cellular lung infiltrate was almost exclusively neutrophils. Parametric Ki maps by Patlak analysis revealed heterogeneous inflammatory foci within infected lungs. Conclusion. The kinetics of FDG uptake in the lungs of mice can be noninvasively quantified by PET with a 3-compartment model approach based on an image-derived input function

A new specie of Stenotabanus (Stenochlorops) (Diptera: Tabanidae) from Amazonas, Brazil, and a key to the subgenus

Description and figures are given tor Stenotabanus (Stenochlorops) bequaerti n. sp. from Amazonas, Brazil. Figures are included for paradoxus (Lutz) and vitripennis (Lutz), and a key to the subgenus is provided.Stenotabanus (Stenochlorops) bequaerti sp. n. do Amazonas, Brasil, é descrita e figurada. São incluídas figuras para vitripennis (Lutz) e paradoxus (Lutz) e uma chave é dada para o subgênero

Fungi in a Warmer World - Fungal diversity from the Peak Warming of the Miocene Climate Optimum as Recorded in the Latah Formation, Clarkia, Idaho, USA

Microfungi are a vital part of ecosystems as they help with key processes, such as carbon and nutrient cycling, especially through the actions of mycorrhizal and saprotrophic members (Nuñez Otaño et al., 2015, 2021; Willis et al., 2018). Microfungi can also be good indicators of plant biodiversity in an area because many fungal taxa are host-specific (Rutten et al., 2021; Francioli et al., 2021; Hu et al., 2021; Wijayawardene et al., 2022 ). Despite being crucial components in ecosystems, they are often overlooked. In the fossil record, microfungi have a high preservaon rate and they are often preserved close to the original substrate they were deposited in. This makes them an important proxy for understanding local past ecological and climatological conditions (Romero et al., 2021, O’Keefe et al., 2017). The Fungi in a Warmer World project seeks to use fossil fungal assemblages to study changes in biodiversity during the Miocene Climate Opmum (MCO), a period of peak warming that closely mirrors current and projected warming trends (Steinthorsdotter et al., 2021). The current atmospheric CO2 concentraon is around 420 ppm but is rapidly approaching the MCO average of 450-550 ppm (Steinthorsdotter et al., 2021).https://scholarworks.moreheadstate.edu/celebration_posters_2022/1045/thumbnail.jp

Macroscopic self standing SWCNT fibers as efficient electron emitters with very high emission current for robust cold cathodes

A novel of self-standing nanotube-based cold cathode is described. The electron emitter is a single macroscopic fibre spun from neat single wall carbon nanotubes and consists of an ensemble of nanotube bundles held together by van der Waals forces. Field emission measurements carried out using two different types of apparatus demonstrated the long working life of the realised cathode. The system is able to emit at very high current densities, up to 13 A/cm2, and shows very low values of both turn on and threshold field, 0.12 V/lm and 0.21 V/lm, respectively. Such easy to handle self-standing electron sources assure good performances and represent an enabling technology for a scalable production of cold cathodes. 2012 Elsevier Ltd. All rights reserved. 1. Introduction Due to a unique combination of properties, including high electrical and thermal conductivity, and high mechanical/ chemical/thermal stability, carbon nanotubes (CNTs) have been recognised as ideal candidate materials for application in microelectronics [1]. Moreover, the high aspect ratio characterising this intriguing material makes possible to significantly strengthen electric fields into the vicinity of nanotubes tips

Field Emission from Self-Assembled Arrays of Lanthanum Monosulfide Nanoprotrusions

The field emission properties of LaS nanoprotrusions called nanodomes, formed by pulsed laser deposition on porous anodic alumina films, have been analyzed with scanning anode field emission microscopy. The voltage necessary to produce a given field emission current is 3.5 times less for nanodomes than for thin films. Assuming the same work function for LaS thin films and nanoprotrusions, that is, 1 eV, a field enhancement factor of 5.8 is extracted for the nanodome emitters from Fowler-Nordheim plots of the field emission data. This correlates well with the aspect ratio of the tallest nanodomes observed in atomic force micrograph measurements

Temporal dynamics of aquatic communities and implications for pond conservation

Conservation through the protection of particular habitats is predicated on the assumption that the conservation value of those habitats is stable. We test this assumption for ponds by investigating temporal variation in macroinvertebrate and macrophyte communities over a 10-year period in northwest England. We surveyed 51 ponds in northern England in 1995/6 and again in 2006, identifying all macrophytes (167 species) and all macroinvertebrates (221 species, excluding Diptera) to species. The alpha-diversity, beta-diversity and conservation value of these ponds were compared between surveys. We find that invertebrate species richness increased from an average of 29. 5 species to 39. 8 species between surveys. Invertebrate gamma-diversity also increased between the two surveys from 181 species to 201 species. However, this increase in diversity was accompanied by a decrease in beta-diversity. Plant alpha-, beta and gamma-diversity remained approximately constant between the two periods. However, increased proportions of grass species and a complete loss of charophytes suggests that the communities are undergoing succession. Conservation value was not correlated between sampling periods in either plants or invertebrates. This was confirmed by comparing ponds that had been disturbed with those that had no history of disturbance to demonstrate that levels of correlation between surveys were approximately equal in each group of ponds. This study has three important conservation implications: (i) a pond with high diversity or high conservation value may not remain that way and so it is unwise to base pond conservation measures upon protecting currently-speciose habitats; (ii) maximising pond gamma-diversity requires a combination of late and early succession ponds, especially for invertebrates; and (iii) invertebrate and plant communities in ponds may require different management strategies if succession occurs at varying rates in the two groups