1,970 research outputs found
Kulturschutz â Arbeitszeitbedarf beim Einsatz von Netzen
The product quality requirements of modern outdoor vegetable cultivation are becoming
more stringent and increasing importance is also attached to a defined guarantee
of yield. These demands may be satisfied by using protective netting.
The working methods employed in practice and the process technology hardly differ.
The differences between individual variants - 1 to 7% per net â are therefore relatively
low, as is the size degression. An average of 1.3 manpower-minutes per m are required
for the complete process. The time requirement per net is about 26.7 min., 13 min.
of which are needed for placement and 11.1 min. for removal. The difference is made
up by transportation to and from the field and loading the nets.
Covering the crop takes up 48 % or almost half the total working time requirement.
Removing the nets accounts for 42 %. 10 % is used in driving to and from the field for
placement and in loading the rolls or bales of netting before placement and after
removal. There is no additional transportation time, as the nets are carried as part of
the relevant transport to and from the field. Removal involves no extra journey times if
the netting is removed from the crop immediately prior to harvesting, the journey to
and from the field then being calculated as part of the working time requirement for
harvesting
Early-Stage Progression of Breast Cancer
Breast cancer can be defined as a group of diseases with heterogeneous origins, molecular profiles and behaviors characterized by uncontrolled proliferation of cells within the mammary tissue. Around one in eight women in the US will develop breast cancer in their lifetime, making it the second most frequently diagnosed cancer behind skin cancer [1]. In 2015, an estimated 231,840 cases of invasive carcinoma were diagnosed, and over 40,000 deaths were caused by breast cancer which accounts for almost 7% of all cancer mortality each year. In 2015, 60,290 cases of in situ breast cancer were diagnosed, representing over 14% of all new cancer cases among women and men. The steep increase in diagnosis of earlyâstage breast cancer over the past 10âyears is believed to be a result of more frequent mammography. However, since over half of these in situ lesions will not progress to invasive breast cancer, controversies have arisen about approaches to treatment and prevention of progression of earlyâstage in situ breast cancer. Understanding the mechanisms of transition of normal breast to in situ preâneoplastic lesions and invasive breast cancer is currently a major focus of breast cancer research with implications for preventive and clinical management of breast cancer. In this review, we give an overview of current knowledge on the molecular and pathological changes that occur during earlyâstage progression of breast cancer and describe some of the current models that are used to study this process
The NASA Ames Research Center one- and two-dimensional stratospheric models. Part 2: The two-dimensional model
The two-dimensional model of stratospheric constituents is presented in detail. The derivation of pertinent transport parameters and the numerical solution of the species continuity equations, including a technique for treating the stiff differential equations that represent the chemical kinetic terms, and appropriate methods for simulating the diurnal variations of the solar zenith angle and species concentrations are discussed. Predicted distributions of tracer constituents (ozone, carbon 14, nitric acid) are compared with observed distributions
The AIB1/NCOA3/SRC-3 Oncogene
A member of the NCOA/SRC/p160 co-activator family, AIB1 is amplified and overexpressed in multiple cancer types, notably breast, ovarian, and pancreatic cancer. Common to all members of the NCOA/SRC/p160 family are bHLH-PAS, receptor interaction, and CBP/p300 interacting activation domains. The protein acts as a scaffold to support the transcriptional activity of many DNA binding transcription factors, such as the ER, AP-1, E2F, NFÎșB, and TEADs. In doing so, the multi-domain protein facilitates chromatin remodeling and oncogenic gene transcription. Further, the AIB1Î4 isoform promotes tumorigenesis and metastasis through interaction with chromatin in the nucleus or at the periphery of the cell. Pathologically, AIB1 promotes the transformation of normal tissue to cancerous lesions in multiple diseases, and loss delays progression. AIB1 has also been implicated in cancer recurrence and pharmacological resistance. We will discuss the structure and isoforms of AIB1, the physiological consequences of its interaction with transcription factors and hormone receptors, and clinical significance of the protein
Environmental effects of SPS: The middle atmosphere
The heavy lift launch vehicle associated with the solar power satellite (SPS) would deposit in the upper atmosphere exhaust and reentry products which could modify the composition of the stratosphere, mesosphere, and lower ionosphere. In order to assess such effects, atmospheric model simulations were performed, especially considering a geographic zone centered at the launch and reentry latitudes
VLA OH and H I Zeeman Observations of the NGC 6334 Complex
We present OH and H I Zeeman observations of the NGC 6334 complex taken with
the Very Large Array. The OH absorption profiles associated with the complex
are relatively narrow (del-v_FWHM ~ 3 km s^1) and single-peaked over most of
the sources. The H I absorption profiles contain several blended velocity
components. One of the compact continuum sources in the complex (source A) has
a bipolar morphology. The OH absorption profiles toward this source display a
gradient in velocity from the northern continuum lobe to the southern continuum
lobe; this velocity gradient likely indicates a bipolar outflow of molecular
gas from the central regions to the northern and southern lobes. Magnetic
fields of the order of 200 microG have been detected toward three discrete
continuum sources in the complex. Virial estimates suggest that the detected
magnetic fields in these sources are of the same order as the critical magnetic
fields required to support the molecular clouds associated with the sources
against gravitational collapse.Comment: 14 pages, 9 postscript figures, accepted for publication in the
Astrophysical Journal (ApJ), tentatively scheduled for vol. 533, Apr. 20,
2000; also available at
http://www.pa.uky.edu/~sarma/RESEARCH/aps_research.htm
Bayesian High-Redshift Quasar Classification from Optical and Mid-IR Photometry
We identify 885,503 type 1 quasar candidates to i<22 using the combination of
optical and mid-IR photometry. Optical photometry is taken from the Sloan
Digital Sky Survey-III: Baryon Oscillation Spectroscopic Survey
(SDSS-III/BOSS), while mid-IR photometry comes from a combination of data from
the Wide-Field Infrared Survey Explorer (WISE) "ALLWISE" data release and
several large-area Spitzer Space Telescope fields. Selection is based on a
Bayesian kernel density algorithm with a training sample of 157,701
spectroscopically-confirmed type-1 quasars with both optical and mid-IR data.
Of the quasar candidates, 733,713 lack spectroscopic confirmation (and 305,623
are objects that we have not previously classified as photometric quasar
candidates). These candidates include 7874 objects targeted as high probability
potential quasars with 3.5<z<5 (of which 6779 are new photometric candidates).
Our algorithm is more complete to z>3.5 than the traditional mid-IR selection
"wedges" and to 2.2<z<3.5 quasars than the SDSS-III/BOSS project. Number counts
and luminosity function analysis suggests that the resulting catalog is
relatively complete to known quasars and is identifying new high-z quasars at
z>3. This catalog paves the way for luminosity-dependent clustering
investigations of large numbers of faint, high-redshift quasars and for further
machine learning quasar selection using Spitzer and WISE data combined with
other large-area optical imaging surveys.Comment: 54 pages, 17 figures; accepted by ApJS Data for tables 1 and 2
available at
http://www.physics.drexel.edu/~gtr/outgoing/optirqsos/data/master_quasar_catalogs.011414.fits.bz2
and
http://www.physics.drexel.edu/~gtr/outgoing/optirqsos/data/optical_ir_quasar_candidates.052015.fits.bz
The VLA Galactic Plane Survey
The VLA Galactic Plane Survey (VGPS) is a survey of HI and 21-cm continuum
emission in the Galactic plane between longitude 18 degrees 67 degr. with
latitude coverage from |b| < 1.3 degr. to |b| < 2.3 degr. The survey area was
observed with the Very Large Array (VLA) in 990 pointings. Short-spacing
information for the HI line emission was obtained by additional observations
with the Green Bank Telescope (GBT). HI spectral line images are presented with
a resolution of 1 arcmin x 1 arcmin x 1.56 km/s (FWHM) and rms noise of 2 K per
0.824 km/s channel. Continuum images made from channels without HI line
emission have 1 arcmin (FWHM) resolution. VGPS images are compared with images
from the Canadian Galactic Plane Survey (CGPS) and the Southern Galactic Plane
Survey (SGPS). In general, the agreement between these surveys is impressive,
considering the differences in instrumentation and image processing techniques
used for each survey. The differences between VGPS and CGPS images are small, <
6 K (rms) in channels where the mean HI brightness temperature in the field
exceeds 80 K. A similar degree of consistency is found between the VGPS and
SGPS. The agreement we find between arcminute resolution surveys of the
Galactic plane is a crucial step towards combining these surveys into a single
uniform dataset which covers 90% of the Galactic disk: the International
Galactic Plane Survey (IGPS). The VGPS data will be made available on the World
Wide Web through the Canadian Astronomy Data Centre (CADC).Comment: Accepted for publication in The Astronomical Journal. 41 pages, 13
figures. For information on data release, colour images etc. see
http://www.ras.ucalgary.ca/VGP
Search for Interstellar Water in the Translucent Molecular Cloud toward HD 154368
We report an upper limit of 9 x 10^{12} cm-2 on the column density of water
in the translucent cloud along the line of sight toward HD 154368. This result
is based upon a search for the C-X band of water near 1240 \AA carried out
using the Goddard High Resolution Spectrograph of the Hubble Space Telescope.
Our observational limit on the water abundance together with detailed chemical
models of translucent clouds and previous measurements of OH along the line of
sight constrain the branching ratio in the dissociative recombination of H_3O+
to form water. We find at the level that no more than 30% of
dissociative recombinations of H_3O+ can lead to H_2O. The observed spectrum
also yielded high-resolution observations of the Mg II doublet at 1239.9 \AA
and 1240.4 \AA, allowing the velocity structure of the dominant ionization
state of magnesium to be studied along the line of sight. The Mg II spectrum is
consistent with GHRS observations at lower spectral resolution that were
obtained previously but allow an additional velocity component to be
identified.Comment: Accepted by ApJ, uses aasp
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