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Neural precursor cells derived from induced pluripotent stem cells exhibit reduced susceptibility to infection with a neurotropic coronavirus.
The present study examines the susceptibility of mouse induced pluripotent stem cell-derived neural precursor cells (iPSC-NPCs) to infection with the neurotropic JHM strain of mouse hepatitis virus (JHMV). Similar to NPCs derived from striatum of day 1 postnatal GFP-transgenic mice (GFP-NPCs), iPSC-derived NPCs (iPSC-NPCs) are able to differentiate into terminal neural cell types and express MHC class I and II in response to IFN-γ treatment. However, in contrast to postnatally-derived NPCs, iPSC-NPCs express low levels of carcinoembryonic antigen-cell adhesion molecule 1a (CEACAM1a), the surface receptor for JHMV, and are less susceptible to infection and virus-induced cytopathic effects. The relevance of this in terms of therapeutic application of NPCs resistant to viral infection is discussed
A Guide to the Attorney-Client Privilege and Work Product Doctrine for Tax Practitioners
The Influence of Epidermal Windows on the Light Environment Within the Leaves of Six Succulents
This is the publisher's official version. It is also available electronically from: http://dx.doi.org/10.1093/jxb/ern105.An omni-directional fibre optic microprobe was used
to measure the quantity and quality of light within the
leaves of six succulents having epidermal windows,
three species having a subterranean growth habit
(Haworthia truncata, Lithops olivacea, and Opthalmophyllum
longum) and three growing above ground
(Peperomia dolabriformis, P. graveolens, and the
sprawling vine Senecio rowleyanus). Although light
levels at most locations inside the leaves of all species
were high, near those incident on the window surfaces,
light levels inside the leaves of the two species of
Peperomia often greatly exceeded incident light levels,
indicating considerable light scattering and focusing
by the leaf tissue. The spectral quality of light inside
the leaves of all taxa reflected the absorption properties
of chlorophyll, with most of the photons in the
green wavelengths. Light quality and quantity inside
the leaves did not correlate with the growth habit of the
plants, the size of the window (as a proportion of the
total leaf area), or location inside the leaf, although
light levels generally declined and wavelengths increased
deeper in the leaves. Application of reflective
tape to the windows reduced internal light levels in
L. olivacea and S. rowleyanus, although reductions
were not always statistically significant. Although light
levels throughout the leaves of P. graveolens were
substantially and significantly reduced as a result of
the application of reflective tape to its windows, the
light levels even at the basal chlorenchyma on the
abaxial side of the leaf remained high. In all species
investigated, the levels of near-infrared radiation inside
the leaves were surprisingly high, yet also declined
deeper inside the succulent leaves. This nearinfrared
radiation may add to the heat load of these
* To whom correspondence should be addressed. E-mail: [email protected]
plants. Furthermore, application of reflective tape to
the windows also reduced the amount of near-infrared
radiation inside the leaves of the three succulents
examined. These results led to a novel, testable
hypothesis that may help to explain previous findings
that application of reflective tape to the windows of the
leaves of these succulents did not effect a reduction in
photosynthetic activity
Integrated soil and weed management production systems for perennial food crops
Several alternative weed management tactics for strawberry and grape production were tested for their effects on weed control, crop yield and soil quality enhancement
Surface Stability in Drylands is Influenced by Dispersal Strategy of Soil Bacteria
Microbial adaptations for survival and dispersal may directly influence landscape stability and potential for dust emission in drylands where biological soil crusts (biocrusts) protect mineral soil surfaces from wind erosion. In the Lake Eyre basin of central Australia we operated a wind tunnel on sandy soils and collected the liberated material, which was subjected to DNA sequencing to identify the microbial community composition. Microbial composition of entrained dust was compared with that of the source sand dune soil in addition to nearby claypan and nebkha soils, and water channels which together form a recycling sediment transport system. Wind was found to preferentially liberate 359 identified taxa from sand dunes whereas 137 identified taxa were found to resist wind erosion. Water channel communities included many taxa in common with the soil samples. We hypothesise that the ease with which soil microbes become airborne is often linked to whether the organism is adapted for dispersal by wind or vegetative growth, and that biocrust organisms found in water channels may sometimes use a fluvial dispersal strategy which exploits rare flooding events to rapidly colonise vast pans which are common in drylands. We explain likely geomorphic implications of microbial dispersal strategies which are a consequence of organisms engineering the environment to provide their particular needs. By identifying microbes fitting expectations for these dispersal strategies based on differential abundance analyses, we provide a new perspective for understanding the role of microbiota in landscape stability.NERC grant ref NE/K011464/
Time-Dependence of the Mass Accretion Rate in Cluster Cooling Flows
We analyze two time-dependent cluster cooling flow models in spherical
symmetry. The first assumes that the intracluster gas resides in a static
external potential, and includes the effects of optically thin radiative
cooling and mass deposition. This corresponds to previous steady-state cooling
flow models calculated by White & Sarazin (1987). Detailed agreement is found
between steady-state models and time-dependent models at fixed times in the
simulations. The mass accretion rate is found either to increase or remain
nearly constant once flows reach a steady state. The time rate of change of the
accretion rate is strongly sensitive to the value of the mass deposition
parameter q, but only mildly sensitive to the ratio beta of gravitational
binding energy to gas temperature. We show that previous scaling arguments
presented by Bertschinger (1988) and White (1988) are valid only for mature
cooling flows with weak mass deposition (q ~< 1). The second set of models
includes the effects of a secularly deepening cluster potential and secondary
infall of gas from the Hubble flow. We find that such heating effects do not
prevent the flows from reaching a steady state within an initial central
cooling time.Comment: 22 pages (AASTeX) with 16 EPS figures; accepted for publication in
The Astrophysical Journa
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