925 research outputs found
Project environmental microbiology as related to planetary quarantine
The viability and dry heat resistance of indigenous microflora associated with small soil particles were investigated. An aluminum boat TDT CUP-TSA solid media system was developed for the analyses; a complete description of the technique is included. Data cited here were obtained using analyses of individual soil particles. Detailed particle viability profiles for dry heat effects were determined for Kennedy Space Center soil. At 110 C at least some particles retained viability through a heating period of between 8 and 16 hours. Single particles heated at 125 C for 80 minutes or longer did not show evidence of viability under test conditions. Preliminary aerobic, mesophilic plate counts of the 74-88 micron m soil fraction yielded mean values of 16.2 organisms per dark particle and 2.6 organisms per light particle. Heat treatment of particles in a dry atmosphere did not appear to increase the rate of inactivation for in situ soil particle microflora
Environmental microbiology as related to planetary quarantine Semiannual progress report, 1 Jun. - 30 Nov. 1969
Survival of bacterial spores under various temperature and humidity conditions related to planetary quarantin
Dry heat effects on survival of indigenous soil particle microflora and particle viability studies of Kennedy Space Center soil
Research efforts were concentrated on attempts to obtain data concerning the dry heat resistance of particle microflora in Kennedy Space Center soil samples. The in situ dry heat resistance profiles at selected temperatures for the aggregate microflora on soil particles of certain size ranges were determined. Viability profiles of older soil samples were compared with more recently stored soil samples. The effect of increased particle numbers on viability profiles after dry heat treatment was investigated. These soil particle viability data for various temperatures and times provide information on the soil microflora response to heat treatment and are useful in making selections for spacecraft sterilization cycles
Generalization of a theorem of Gonchar
Let be two complex manifolds, let be two
nonempty open sets, let (resp. ) be an open subset of
(resp. ), and let be the 2-fold cross
Under a geometric condition on the boundary sets and we show that
every function locally bounded, separately continuous on continuous on
and separately holomorphic on
"extends" to a function continuous on a "domain of holomorphy" and
holomorphic on the interior of Comment: 14 pages, to appear in Arkiv for Matemati
Lipschitzness of the Lempert and Green functions
Necessary and sufficient conditions for Lipschitzness of the Lempert and
Green functions are found in terms of their boundary behaviors.Comment: minor change
Interactions between thresholds and spatial discretizations of snow: insights from estimates of wolverine denning habitat in the Colorado Rocky Mountains
Thresholds can be used to interpret environmental data in a way
that is easily communicated and useful for decision-making purposes.
However, thresholds are often developed for specific data products and time
periods, changing findings when the same threshold is applied to datasets or
periods with different characteristics. Here, we test the impact of
different spatial discretizations of snow on annual estimates of wolverine
denning opportunities in the Colorado Rocky Mountains, defined using a snow
water equivalent (SWE) threshold (0.20 m) and threshold date (15 May) from
previous habitat assessments. Annual potential wolverine denning area (PWDA)
was thresholded from a 36-year (1985–2020) snow reanalysis model with
three different spatial discretizations: (1) 480 m grid cells (D480), (2) 90 m
grid cells (D90), and (3) 480 m grid cells with implicit representations of
subgrid snow spatial heterogeneity (S480). Relative to the D480 and S480
discretizations, D90 resolved shallower snow deposits on slopes between 3050
and 3350 m elevation, decreasing PWDA by 10 %, on average. In years with
warmer and/or drier winters, S480 discretizations with subgrid
representations of snow heterogeneity increased PWDA, even within grid cells
where mean 15 May SWE was less than the SWE threshold. These simulations
increased PWDA by upwards of 30 % in low-snow years, as compared to the
D480 and D90 simulations without subgrid snow heterogeneity. Despite PWDA
sensitivity to different snow spatial discretizations, PWDA was controlled
more by annual variations in winter precipitation and temperature. However,
small changes to the SWE threshold (±0.07 m) and threshold date
(±2 weeks) also affected PWDA by as much as 82 %. Across these
threshold ranges, PWDA was approximately 18 % more sensitive to the SWE
threshold than the threshold date. However, the sensitivity to the threshold
date was larger in years with late spring snowfall, when PWDA depended on
whether modeled SWE was thresholded before, during, or after spring snow
accumulation. Our results demonstrate that snow thresholds are useful but
may not always provide a complete picture of the annual variability in
snow-adapted wildlife denning opportunities. Studies thresholding
spatiotemporal datasets could be improved by including (1) information about
the fidelity of thresholds across multiple spatial discretizations and (2) uncertainties related to ranges of realistic thresholds.</p
On a local characterization of pseudoconvex domains
Pseudoconvexity of a domain in is described in terms of the
existence of a locally defined plurisubharmonic/holomorphic function near any
boundary point that is unbounded at the point
Entire curves avoiding given sets in C^n
Let be a proper closed subset of and
at most countable (). We give conditions
of and , under which there exists a holomorphic immersion (or a proper
holomorphic embedding) with .Comment: 10 page
Exhausting domains of the symmetrized bidisc
We show that the symmetrized bidisc may be exhausted by strongly linearly
convex domains. It shows in particular the existence of a strongly linearly
convex domain that cannot be exhausted by domains biholomorphic to convex ones.Comment: 6 page
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