278 research outputs found
Within-host transmission strategies of transovarial, feminizing parasites of Gammarus duebeni
The amphipod Gammarus duebeni harbours several species of vertically transmitted, feminizing microsporidian parasites. G. duebeni were collected from 3 localities in the UK. Animals from Budle Bay, Northumberland, were infected with Octosporea effeminans, and those from Millport, Isle of Cumbrae and Fenham Flats, Northumberland were infected with microsporidia of the genus Nosema. We derived expected distributions of parasites per host embryonic cell by modelling parasite transmission as a multitype, Galton–Watson branching process. Parasite prevalence (proportion of females infected) was significantly heterogeneous among localities. Parasite burden in zygotes was much higher for females infected with Nosema than in animals infected with O. effeminans. There was no significant difference between localities in the number of Nosema in the zygotes. Comparison of models and data from 64-cell host embryos showed that the distributions of parasites per cell were consistent with the hypothesis that sorting of parasites into daughter cells is biased for at least 1 cell lineage. Host embryos infected with O. effeminans could expect to contain a growing number of parasites in each cell generation within such biased cell lineages; similar estimates for Nosema predict a decline in the number of parasites per cell within a biased lineage. We discuss the possibility that the 2 species of parasite may be employing different strategies in order to ensure transmission to the next host generation
Perceptual Pluralism
Perceptual systems respond to proximal stimuli by forming mental representations of distal stimuli. A central goal for the philosophy of perception is to characterize the representations delivered by perceptual systems. It may be that all perceptual representations are in some way proprietarily perceptual and differ from the representational format of thought (Dretske 1981; Carey 2009; Burge 2010; Block ms.). Or it may instead be that perception and cognition always trade in the same code (Prinz 2002; Pylyshyn 2003). This paper rejects both approaches in favor of perceptual pluralism, the thesis that perception delivers a multiplicity of representational formats, some proprietary and some shared with cognition. The argument for perceptual pluralism marshals a wide array of empirical evidence in favor of iconic (i.e., image-like, analog) representations in perception as well as discursive (i.e., language-like, digital) perceptual object representations
HadISDH: an updateable land surface specific humidity product for climate monitoring
HadISDH is a near-global land surface specific humidity monitoring product providing monthly means from 1973 onwards over large-scale grids. Presented herein to 2012, annual updates are anticipated. HadISDH is an update to the land component of HadCRUH, utilising the global high-resolution land surface station product HadISD as a basis. HadISD, in turn, uses an updated version of NOAA's Integrated Surface Database. Intensive automated quality control has been undertaken at the individual observation level, as part of HadISD processing. The data have been subsequently run through the pairwise homogenisation algorithm developed for NCDC's US Historical Climatology Network monthly temperature product. For the first time, uncertainty estimates are provided at the grid-box spatial scale and monthly timescale.
HadISDH is in good agreement with existing land surface humidity products in periods of overlap, and with both land air and sea surface temperature estimates. Widespread moistening is shown over the 1973–2012 period. The largest moistening signals are over the tropics with drying over the subtropics, supporting other evidence of an intensified hydrological cycle over recent years. Moistening is detectable with high (95%) confidence over large-scale averages for the globe, Northern Hemisphere and tropics, with trends of 0.089 (0.080 to 0.098) g kg−1 per decade, 0.086 (0.075 to 0.097) g kg−1 per decade and 0.133 (0.119 to 0.148) g kg−1 per decade, respectively. These changes are outside the uncertainty range for the large-scale average which is dominated by the spatial coverage component; station and grid-box sampling uncertainty is essentially negligible on large scales. A very small moistening (0.013 (−0.005 to 0.031) g kg−1 per decade) is found in the Southern Hemisphere, but it is not significantly different from zero and uncertainty is large. When globally averaged, 1998 is the moistest year since monitoring began in 1973, closely followed by 2010, two strong El Niño years. The period in between is relatively flat, concurring with previous findings of decreasing relative humidity over land
A Review of Recent Developments in Atomic Processes for Divertors and Edge Plasmas
The most promising concepts for power and particle control in tokamaks and
other fusion experiments rely upon atomic processes to transfer the power and
momentum from the edge plasma to the plasma chamber walls. This places a new
emphasis on processes at low temperatures (1-200 eV) and high densities
(10^20-10^22 m^-3). The most important atomic processes are impurity and
hydrogen radiation, ionization, excitation, recombination, charge exchange,
radiation transport, molecular collisions, and elastic scattering of atoms,
molecules and ions. Important new developments have occurred in each of these
areas. The best available data for these processes and an assessment of their
role in plasma wall interactions are summarized, and the major areas where
improved data are needed are reviewed.Comment: Preprint for the 11th PSI meeting, postscript with 22 figures, 40
page
Translation to practice: a randomised controlled study of an evidenced based booklet targeted at breast care nurses in the United Kingdom
BACKGROUND: In the United Kingdom (UK), it was documented that a problem of knowledge transfer existed within the speciality of breast-cancer care, thus depriving patients of receiving optimal care. Despite increasingly robust research evidence indicating recommendation of whole body exercise for people affected by breast cancer, commensurate changes to practice were not noted amongst breast-care nurses (BCNs).
AIM: To evaluate the effect of a targeted booklet, Exercise and Breast Cancer: A Booklet for Breast-Care Nurses, on changes in knowledge, reported practice, and attitudes of BCNs in the UK.
METHOD: A prospective, experimental approach was used for designing a pre- and post-test randomised controlled study. Comparisons of knowledge, reported practice, and attitudes based on responses to a questionnaire were made at two time-points in two groups of BCNs (control and experimental). The unit of randomisation and analysis was hospital clusters of BCNs. The sample comprised 92 nurses from 62 hospitals. Analysis consisted of descriptive statistics and clustered regression techniques: clustered logistic regression for knowledge items, clustered linear regression for knowledge scores, ologit for attitude and reported practice items, and clustered multiple regression for paired and multiple variable analysis.
RESULTS: A statistically significant increase in knowledge and changes in reported practice and attitudes were found. Robust variables affecting knowledge acquisition were: promotion of health, promotion of exercise, and understanding how exercise can reduce cancer-related fatigue.
DISCUSSION: The study has shown that evidence-based printed material, such as an information booklet, can be used as an effective research dissemination method when developed for needs, values, and context of a target audience.
CONCLUSIONS: This practical approach to research dissemination could be replicated and applied to other groups of nurses.</p
An overview of jets and outflows in stellar mass black holes
In this book chapter, we will briefly review the current empirical
understanding of the relation between accretion state and and outflows in
accreting stellar mass black holes. The focus will be on the empirical
connections between X-ray states and relativistic (`radio') jets, although we
are now also able to draw accretion disc winds into the picture in a systematic
way. We will furthermore consider the latest attempts to measure/order jet
power, and to compare it to other (potentially) measurable quantities, most
importantly black hole spin.Comment: Accepted for publication in Space Science Reviews. Also to appear in
the Space Sciences Series of ISSI - The Physics of Accretion on to Black
Holes (Springer Publisher
Multiwavelength studies of MHD waves in the solar chromosphere: An overview of recent results
The chromosphere is a thin layer of the solar atmosphere that bridges the
relatively cool photosphere and the intensely heated transition region and
corona. Compressible and incompressible waves propagating through the
chromosphere can supply significant amounts of energy to the interface region
and corona. In recent years an abundance of high-resolution observations from
state-of-the-art facilities have provided new and exciting ways of
disentangling the characteristics of oscillatory phenomena propagating through
the dynamic chromosphere. Coupled with rapid advancements in
magnetohydrodynamic wave theory, we are now in an ideal position to thoroughly
investigate the role waves play in supplying energy to sustain chromospheric
and coronal heating. Here, we review the recent progress made in
characterising, categorising and interpreting oscillations manifesting in the
solar chromosphere, with an impetus placed on their intrinsic energetics.Comment: 48 pages, 25 figures, accepted into Space Science Review
B7-H3-redirected chimeric antigen receptor T cells target glioblastoma and neurospheres
Background: The dismal survival of glioblastoma (GBM) patients urgently calls for the development of new treatments. Chimeric antigen receptor T (CAR-T) cells are an attractive strategy, but preclinical and clinical studies in GBM have shown that heterogeneous expression of the antigens targeted so far causes tumor escape, highlighting the need for the identification of new targets. We explored if B7-H3 is a valuable target for CAR-T cells in GBM. Methods: We compared mRNA expression of antigens in GBM using TCGA data, and validated B7-H3 expression by immunohistochemistry. We then tested the antitumor activity of B7-H3-redirected CAR-T cells against GBM cell lines and patient-derived GBM neurospheres in vitro and in xenograft murine models. Findings: B7-H3 mRNA and protein are overexpressed in GBM relative to normal brain in all GBM subtypes. Of the 46 specimens analyzed by immunohistochemistry, 76% showed high B7-H3 expression, 22% had detectable, but low B7-H3 expression and 2% were negative, as was normal brain. All 20 patient-derived neurospheres showed ubiquitous B7-H3 expression. B7-H3-redirected CAR-T cells effectively targeted GBM cell lines and neurospheres in vitro and in vivo. No significant differences were found between CD28 and 4-1BB co-stimulation, although CD28-co-stimulated CAR-T cells released more inflammatory cytokines. Interpretation: We demonstrated that B7-H3 is highly expressed in GBM specimens and neurospheres that contain putative cancer stem cells, and that B7-H3-redirected CAR-T cells can effectively control tumor growth. Therefore, B7-H3 represents a promising target in GBM. Fund: Alex's Lemonade Stand Foundation; Il Fondo di Gio Onlus; National Cancer Institute; Burroughs Wellcome Fund
Solubilization of Proteins in 2DE: An Outline
Protein solubilization for two-dimensional electrophoresis (2DE) has to break
molecular interactions to separate the biological contents of the material of
interest into isolated and intact polypeptides. This must be carried out in
conditions compatible with the first dimension of 2DE, namely isoelectric
focusing. In addition, the extraction process must enable easy removal of any
nonprotein component interfering with the isoelectric focusing. The constraints
brought in this process by the peculiar features of isoelectric focusing are
discussed, as well as their consequences in terms of possible solutions and
limits for the solubilization process
Classification, expression pattern and comparative analysis of sugarcane expressed sequences tags (ESTs) encoding glycine-rich proteins (GRPs)
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