Understanding the function of fat metabolism during differentiation of human preadipocytes to fully developed fat tissue has been the aim of various studies in the past decades. Due to the lack of ...suitable human cell culture lines, experimental research predominantly focused on rodent models and nonhuman cell culture systems. Here, we demonstrate that a human preadipocyte cell line SGBS is well suited to examine differential expression of the Acyl-CoA binding protein (ACBP) during adipogenesis. The Acbp gene expresses various alternative high- and low-abundant transcript variants encoding ACBP protein isoforms, which play a central role in fat metabolism. Whereas the low-abundant transcript Acbp-1G is downregulated during SGBS adipogenesis, the high-abundant and well established transcripts Acbp-1A (1) and -1B are moderately (2-4-fold) upregulated. In contrast, the alternative high-abundant transcript Acbp-1C is strongly (29-fold) upregulated at mRNA and protein level indicating that particularly ACBP-1C functions in lipogenic processes during fat cell differentiation in humans.
The effects of temperature (4–20°C), relative humidity (RH, 0–100%), pH (3–7), availability of nutrients (0–5 g/l sucrose) and artificial light (0–494 μmol/m2/s) on macroconidial germination of ...Fusarium graminearum were studied. Germ tubes emerged between 2 and 6 h after inoculation at 100% RH and 20°C. Incubation in light (205 ± 14 μmol/m/s) retarded the germination for approximately 0.5 h in comparison with incubation in darkness. The times required for 50% of the macroconidia to germinate were 3.5 h at 20°C, 5.4 h at 14°C and 26.3 h at 4°C. No germination was observed after an incubation period of 18 h at 20°C in darkness at RH less than 80%. At RH greater than 80%, germination increased with humidity. Germination was observed when macroconidia were incubated in glucose (5 g/l) or sucrose (concentration range from 2.5 × 10−4 to 5 g/l) whereas no germination was observed when macroconidia were incubated in sterile deionized water up to 22 h. Macroconidia germinated quantitatively within 18 h at pH 3–7. Repeated freezing (−15°C) and thawing (20°C) water agar plates with either germinated or non‐germinated macroconidia for up to five times did not prevent fungal growth after thawing. However, the fungal growth rate of mycelium was negatively related to the number of freezing events the non‐germinated macroconidia experienced. The fungal growth rate of mycelium was not significantly affected by the number of freezing events the germinated spores experienced. Incubation of macroconidia at low humidity (0–53% RH) suppressed germination and decreased the viability of the spores.
Nitrogen dioxide (NO2) is one of the main data products measured by the Tropospheric Monitoring Instrument (TROPOMI) on the Sentinel-5 Precursor (S5P) satellite, which combines a high signal-to-noise ...ratio with daily global coverage and high spatial resolution. TROPOMI provides a valuable source of information to monitor emissions from local sources such as power plants, industry, cities, traffic and ships, and variability of these sources in time. Validation exercises of NO2 v1.2–v1.3 data, however, have revealed that TROPOMI's tropospheric vertical column densities (VCDs) are too low by up to 50 % over highly polluted areas. These findings are mainly attributed to biases in the cloud pressure retrieval, the surface albedo climatology and the low resolution of the a priori profiles derived from global simulations of the TM5-MP chemistry model.This study describes improvements in the TROPOMI NO2 retrieval leading to version v2.2, operational since 1 July 2021. Compared to v1.x, the main changes are the following. (1) The NO2-v2.2 data are based on version-2 level-1b (ir)radiance spectra with improved calibration, which results in a small and fairly homogeneous increase in the NO2 slant columns of 3 % to 4 %, most of which ends up as a small increase in the stratospheric columns. (2) The cloud pressures are derived with a new version of the FRESCO cloud retrieval already introduced in NO2-v1.4, which led to a lowering of the cloud pressure, resulting in larger tropospheric NO2 columns over polluted scenes with a small but non-zero cloud coverage. (3) For cloud-free scenes a surface albedo correction is introduced based on the observed reflectance, which also leads to a general increase in the tropospheric NO2 columns over polluted scenes of order 15 %. (4) An outlier removal was implemented in the spectral fit, which increases the number of good-quality retrievals over the South Atlantic Anomaly region and over bright clouds where saturation may occur. (5) Snow/ice information is now obtained from ECMWF weather data, increasing the number of valid retrievals at high latitudes.On average the NO2-v2.2 data have tropospheric VCDs that are between 10 % and 40 % larger than the v1.x data, depending on the level of pollution and season; the largest impact is found at mid and high latitudes in wintertime. This has brought these tropospheric NO2 closer to Ozone Monitoring Instrument (OMI) observations. Ground-based validation shows on average an improvement of the negative bias of the stratospheric (from -6 % to -3 %), tropospheric (from -32 % to -23 %) and total (from -12 % to -5 %) columns. For individual measurement stations, however, the picture is more complex, in particular for the tropospheric and total columns.
After the launch of the Sentinel-5 Precursor satellite on 13 October 2017, its single payload, the TROPOspheric Monitoring Instrument (TROPOMI), was commissioned for 6 months. In this time the ...instrument was tested and calibrated extensively. During this phase the geolocation calibration was validated using a dedicated measurement zoom mode. With the help of spacecraft manoeuvres the solar angle dependence of the irradiance radiometry was calibrated for both internal diffusers. This improved the results that were obtained on the ground significantly. Furthermore the orbital and long-term stability was tested for electronic gains, offsets, non-linearity, the dark current and the output of the internal light sources. The CCD output gain of the UV, UVIS and NIR detectors shows drifts over time which can be corrected in the Level 1b (L1b) processor. In-flight measurements also revealed inconsistencies in the radiometric calibration and degradation of the UV spectrometer. Degradation was also detected for the internal solar diffusers. Since the start of the nominal operations (E2) phase in orbit 2818 on 30 April 2018, regularly scheduled calibration measurements on the eclipse side of the orbit are used for monitoring and updates to calibration key data. This article reports on the main results of the commissioning phase, the in-flight calibration and the instrument's stability since launch. Insights from commissioning and in-flight monitoring have led to updates to the L1b processor and its calibration key data. The updated processor is planned to be used for nominal processing from late 2020 on.
We report on the observation of Bragg scattering at 1D atomic lattices. Cold atoms are confined by optical dipole forces at the antinodes of a standing wave generated by the two counterpropagating ...modes of a laser-driven high-finesse ring cavity. By heterodyning the Bragg-scattered light with a reference beam, we obtain detailed information on phase shifts imparted by the Bragg scattering process. Being deep in the Lamb-Dicke regime, the scattered light is not broadened by the motion of individual atoms.
The Sentinel-5 Precursor satellite was successfully launched on 13 October 2017, carrying the Tropospheric Monitoring Instrument (TROPOMI) as its single
payload. TROPOMI is the next-generation ...atmospheric sounding instrument,
continuing the successes of GOME, SCIAMACHY, OMI, and OMPS, with higher
spatial resolution, improved sensitivity, and extended wavelength range. The
instrument contains four spectrometers, divided over two modules sharing a
common telescope, measuring the ultraviolet, visible, near-infrared, and
shortwave infrared reflectance of the Earth. The imaging system enables daily
global coverage using a push-broom configuration, with a spatial resolution
as low as 7×3.5 km2 in nadir from a Sun-synchronous orbit at
824 km and an Equator crossing time of 13:30 local solar time. This article reports the pre-launch calibration status of the TROPOMI payload
as derived from the on-ground calibration effort. Stringent requirements are
imposed on the quality of on-ground calibration in order to match the high
sensitivity of the instrument. A new methodology has been employed during the analysis of the obtained
calibration measurements to ensure the consistency and validity of the
calibration. This was achieved by using the production-grade Level 0 to 1b
data processor in a closed-loop validation set-up. Using this approach the
consistency between the calibration and the L1b product,
as well as confidence in the obtained calibration result, could be established. This article introduces this novel calibration approach and describes all
relevant calibrated instrument properties as they were derived before launch
of the mission. For most of the relevant properties compliance with the
calibration requirements could be established, including the knowledge of the
instrument spectral and spatial response functions. Partial compliance was
established for the straylight correction; especially the
out-of-spectral-band correction for the near-infrared channel needs future validation.
The absolute radiometric calibration of the radiance and irradiance
responsivity is compliant with the high-level mission requirements, but not
with the stricter calibration requirements as the available on-ground
validation shows. The relative radiometric calibration of the Sun port was
non-compliant. The non-compliant subjects will be addressed during the
in-flight commissioning phase in the first 6 months following launch.
The design of our source of negatively charged, intense and brilliant DC beams of polarized hydrogen and deuterium ions was motivated by the excellent performance of the HERMES atomic beam source and ...the successful operation of a polarized ion source at TUNL. Deviating from their 30
K atomic beam technology we combine an 80
K atomic beam source (ABS) with subsequent ionization in an electron cyclotron resonance (ECR) plasma. In a separate unit, negative ions are obtained by successive two electron pickup from cesium in a vapour jet target. Our ABS provides a flux of
6.4
×
10
16
atoms
/
s
for hydrogen and of about
5
×
10
16
atoms
/
s
for deuterium into a compression tube of 10
mm diameter and 100
mm length. Polarized negative
D
-
⇒
/
H
-
⇒
ion beams of about
9
μ
A
/
15
μ
A
with an emittance of
20
π
mm
rad
eV
have been observed. After tandem acceleration we have polarized beam intensity of
2
μ
A
on target of the Q3D spectrograph. The measured vector polarizations of the
D
⇒
and
H
⇒
ion beams are 72% and 67%, respectively, in accordance with expectations from source operation data. Using an external gas inlet for the ECR region, intense beams of unpolarized
1
H
-
,
2
D
-
,
3
He
-
, and
4
He
-
ions are obtained.
We demonstrate a two-dimensional magneto-optical trap (2D MOT) as a beam source for cold {sup 6}Li atoms. The source is side loaded from an oven operated at temperatures in the range 600 < or approx. ...T < or approx. 700 K. The performance is analyzed by loading the atoms into a three-dimensional MOT located 220 mm downstream from the source. The maximum recapture rate of {approx}10{sup 9} s{sup -1} is obtained for T{approx_equal}700 K and results in a total of up to 10{sup 10} trapped atoms. The recaptured fraction is estimated to be 30{+-}10% and limited by beam divergence. The most-probable velocity in the beam ({alpha}{sub z}) is varied from 18 to 70 m/s by increasing the intensity of a push beam. The source is quite monochromatic with a full width at half maximum velocity spread of 11 m/s at {alpha}{sub z}=36 m/s, demonstrating that side loading completely eliminates beam contamination by hot vapor from the oven. We identify depletion of the low-velocity tail of the oven flux as the limiting loss mechanism. Our approach is suitable for other atomic species.
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