Thinking the unthinkable: Imagining an ‘un-American,’ Girl-friendly, Women- and Trans-Inclusive Alternative for Baseball

The purpose of this article is twofold: to capture the injustice inherent in the gendered bifurcation of baseball and softball via the prism of critical feminist sport studies; and to begin to imagine a girl-friendly/women-and trans-inclusive future for baseball that is less fertile for cooptation into post-911 United States security state discourses. In this article I link the "unthinkability" of the occupational segregation of baseball in North America to the dominance of the ideology of the two sex system and European disasporic morality. To illustrate the extent of this occupational segregation via the gendered bifurcation of baseball and softball, I draw on feminist sport studies to examine the exemplars or "texts" of three Canadian brother/sister baseball softball duos: Jason Bay and Lauren Bay Regula; Brett and Danielle Lawrie; and Mathew and Katie Reyes

Meta-classification of remote sensing reflectance to estimate trophic status of inland and nearshore waters

Common aquatic remote sensing algorithms estimate the trophic state (TS) of inland and nearshore waters through the inversion of remote sensing reflectance (Rrs ()) into chlorophyll-a (chla) concentration. In this study we present a novel method that directly inverts Rrs () into TS without prior chla retrieval. To successfully cope with the optical diversity of inland and nearshore waters the proposed method stacks supervised classification algorithms and combines them through meta-learning. We demonstrate the developed methodology using the waveband configuration of the Sentinel-3 Ocean and Land Colour Instrument on 49 globally distributed inland and nearshore waters (567 observations). To assess the performance of the developed approach, we compare the results with TS derived through optical water type (OWT) switching of chla retrieval algorithms. Meta-classification of TS was on average 6.75% more accurate than TS derived via OWT switching of chla algorithms. The presented method achieved 90% classification accuracies for eutrophic and hypereutrophic waters and was 12% more accurate for oligotrophic waters than derived through OWT chla retrieval. However, mesotrophic waters were estimated with lower accuracy from both our developed method and through OWT chla retrieval (52.17% and 46.34%, respectively), highlighting the need for improved base algorithms for low - moderate biomass waters. Misclassified observations were characterised by highly absorbing and/or scattering optical properties for which we propose adaptations to our classification strategy

Verticalization of bacterial biofilms

Biofilms are communities of bacteria adhered to surfaces. Recently, biofilms of rod-shaped bacteria were observed at single-cell resolution and shown to develop from a disordered, two-dimensional layer of founder cells into a three-dimensional structure with a vertically-aligned core. Here, we elucidate the physical mechanism underpinning this transition using a combination of agent-based and continuum modeling. We find that verticalization proceeds through a series of localized mechanical instabilities on the cellular scale. For short cells, these instabilities are primarily triggered by cell division, whereas long cells are more likely to be peeled off the surface by nearby vertical cells, creating an "inverse domino effect". The interplay between cell growth and cell verticalization gives rise to an exotic mechanical state in which the effective surface pressure becomes constant throughout the growing core of the biofilm surface layer. This dynamical isobaricity determines the expansion speed of a biofilm cluster and thereby governs how cells access the third dimension. In particular, theory predicts that a longer average cell length yields more rapidly expanding, flatter biofilms. We experimentally show that such changes in biofilm development occur by exploiting chemicals that modulate cell length.Comment: Main text 10 pages, 4 figures; Supplementary Information 35 pages, 15 figure

Burkholderia Type VI Secretion Systems Have Distinct Roles in Eukaryotic and Bacterial Cell Interactions

Bacteria that live in the environment have evolved pathways specialized to defend against eukaryotic organisms or other bacteria. In this manuscript, we systematically examined the role of the five type VI secretion systems (T6SSs) of Burkholderia thailandensis (B. thai) in eukaryotic and bacterial cell interactions. Consistent with phylogenetic analyses comparing the distribution of the B. thai T6SSs with well-characterized bacterial and eukaryotic cell-targeting T6SSs, we found that T6SS-5 plays a critical role in the virulence of the organism in a murine melioidosis model, while a strain lacking the other four T6SSs remained as virulent as the wild-type. The function of T6SS-5 appeared to be specialized to the host and not related to an in vivo growth defect, as ΔT6SS-5 was fully virulent in mice lacking MyD88. Next we probed the role of the five systems in interbacterial interactions. From a group of 31 diverse bacteria, we identified several organisms that competed less effectively against wild-type B. thai than a strain lacking T6SS-1 function. Inactivation of T6SS-1 renders B. thai greatly more susceptible to cell contact-induced stasis by Pseudomonas putida, Pseudomonas fluorescens and Serratia proteamaculans—leaving it 100- to 1000-fold less fit than the wild-type in competition experiments with these organisms. Flow cell biofilm assays showed that T6S-dependent interbacterial interactions are likely relevant in the environment. B. thai cells lacking T6SS-1 were rapidly displaced in mixed biofilms with P. putida, whereas wild-type cells persisted and overran the competitor. Our data show that T6SSs within a single organism can have distinct functions in eukaryotic versus bacterial cell interactions. These systems are likely to be a decisive factor in the survival of bacterial cells of one species in intimate association with those of another, such as in polymicrobial communities present both in the environment and in many infections

Acquired Type III Secretion System Determines Environmental Fitness of Epidemic Vibrio parahaemolyticus in the Interaction with Bacterivorous Protists

Genome analyses of marine microbial communities have revealed the widespread occurrence of genomic islands (GIs), many of which encode for protein secretion machineries described in the context of bacteria-eukaryote interactions. Yet experimental support for the specific roles of such GIs in aquatic community interactions remains scarce. Here, we test for the contribution of type III secretion systems (T3SS) to the environmental fitness of epidemic Vibrio parahaemolyticus. Comparisons of V. parahaemolyticus wild types and T3SS-defective mutants demonstrate that the T3SS encoded on genome island VPaI-7 (T3SS-2) promotes survival of V. parahaemolyticus in the interaction with diverse protist taxa. Enhanced persistence was found to be due to T3SS-2 mediated cytotoxicity and facultative parasitism of V. parahaemolyticus on coexisting protists. Growth in the presence of bacterivorous protists and the T3SS-2 genotype showed a strong correlation across environmental and clinical isolates of V. parahaemolyticus. Short-term microcosm experiments provide evidence that protistan hosts facilitate the invasion of T3SS-2 positive V. parahaemolyticus into a coastal plankton community, and that water temperature and productivity further promote enhanced survival of T3SS-2 positive V. parahaemolyticus. This study is the first to describe the fitness advantage of GI-encoded functions in a microbial food web, which may provide a mechanistic explanation for the global spread and the seasonal dynamics of V. parahaemolyticus pathotypes, including the pandemic serotype cluster O3:K6, in aquatic environments

Magnetic resonance imaging indicators of blood-brain barrier and brain water changes in young rats with kaolin-induced hydrocephalus

<p>Abstract</p> <p>Background</p> <p>Hydrocephalus is associated with enlargement of cerebral ventricles. We hypothesized that magnetic resonance (MR) imaging parameters known to be influenced by tissue water content would change in parallel with ventricle size in young rats and that changes in blood-brain barrier (BBB) permeability would be detected.</p> <p>Methods</p> <p>Hydrocephalus was induced by injection of kaolin into the cisterna magna of 4-week-old rats, which were studied 1 or 3 weeks later. MR was used to measure longitudinal and transverse relaxation times (T1 and T2) and apparent diffusion coefficients in several regions. Brain tissue water content was measured by the wet-dry weight method, and tissue density was measured in Percoll gradient columns. BBB permeability was measured by quantitative imaging of changes on T1-weighted images following injection of gadolinium diethylenetriamine penta-acetate (Gd-DTPA) tracer and microscopically by detection of fluorescent dextran conjugates.</p> <p>Results</p> <p>In nonhydrocephalic rats, water content decreased progressively from age 3 to 7 weeks. T1 and T2 and apparent diffusion coefficients did not exhibit parallel changes and there was no evidence of BBB permeability to tracers. The cerebral ventricles enlarged progressively in the weeks following kaolin injection. In hydrocephalic rats, the dorsal cortex was more dense and the white matter less so, indicating that the increased water content was largely confined to white matter. Hydrocephalus was associated with transient elevation of T1 in gray and white matter and persistent elevation of T2 in white matter. Changes in the apparent diffusion coefficients were significant only in white matter. Ventricle size correlated significantly with dorsal water content, T1, T2, and apparent diffusion coefficients. MR imaging showed evidence of Gd-DTPA leakage in periventricular tissue foci but not diffusely. These correlated with microscopic leak of larger dextran tracers.</p> <p>Conclusions</p> <p>MR characteristics cannot be used as direct surrogates for water content in the immature rat model of hydrocephalus, probably because they are also influenced by other changes in tissue composition that occur during brain maturation. There is no evidence for widespread persistent opening of BBB as a consequence of hydrocephalus in young rats. However, increase in focal BBB permeability suggests that periventricular blood vessels may be disrupted.</p

Simultaneous recording of evoked potentials and T2*-weighted MR images during somatosensory stimulation of rat

Somatosensory evoked potentials (SEP) and T2*-weighted nuclear magnetic resonance (NMR) images were recorded simultaneously during somatosensory stimulation of rat to investigate the relationship between electrical activation of the brain tissue and the signal intensity change in functional NMR imaging. Electrical forepaw stimulation was performed in Wistar rats anesthetized with -chloralose. SEPs were recorded with calomel electrodes at stimulation frequencies of 1.5, 3, 4.5, and 6 Hz. At the same time, T2*-weighted imaging was performed, and the signal intensity increase during stimulation was correlated with the mean amplitude of the SEP. Both the stimulation-evoked signal intensity increase in T2*-weighted images and the amplitude of SEPs were dependent on the stimulation frequency, with the largest signals at a stimulation frequency of 1.5 Hz and decreasing activations with increasing frequencies. The feasibility of simultaneous, artifact-free recordings of T2*-weighted NMR images and of evoked potentials is proved. Furthermore, the study demonstrates - in the intact brain - the validity of functional magnetic resonance imaging for estimating the intensity of electrocortical activation

Coup d'oeil sur le Paraguay

A view of Paraguay. Paraguay is situated in South America, covers 406.500 km2 and has a population of 3.500.000 inhabitants. The river Paraguay divides the land in two different areas : Eastern Paraguay with sub-tropical and rather humid climate and Western Paraguay (Chaco), a semi-arid expanse. The most important economic sector is farming, especially ranching and cotton cultivation. Yet, the agricultural resources are still underexploited and the knowledge of the environment should be deepened