239 research outputs found
242. Analiza ekspresji EGFR i angiogenezv w utkaniu niedrobnokomórkowego raka płuc oraz związku z czasem przeżycia pacjentów w stadiach zaawansowania klinicznego I-IIIA
Cel pracyWciąż niezadowalające wskaźniki przeżycia pacjentów z rakiem płuca, mimo radykalnego leczenia operacyjnego, skłaniają do poszukiwań nowych czynników prognostycznych. Wiadomym jest, że receptor naskórkowego czynnika wzrostu (EGFR) wpływa na wzrost komórek guza i jego progresję, jak również tworzenie przerzutów – głównie poprzez oddziaływanie na tworzenie nowych naczyń krwionośnych. Jego prognostyczna rola u pacjentów z niedrobnokomórkowym rakiem płuca (NRP) jest niejasna. Natomiast gęstość naczyń krwionośnych (GNK), będąca miernikiem angiogenezy w guzie, jest podawana jako marker prognostyczny w wielu nowotworach. Celem naszego badania była ocena zależności między ekspresją EGFR i GNK w utkaniu guza nowotworowego a przeżyciem pacjentów z NRP.Materiał i metodyBadaniem objęto 75 pacjentów z NRP w stadiach zaawansowania klinicznego I-IIIA. Wycinki z guza pobierano z materiału operacyjnego, utrwalonego w formalinie. Na uzyskanych skrawkach parafinowych wykonywano odczyny immunohistochemiczne z zastosowaniem monoklonalnego przeciwciała przeciw receptorowi naskórkowego czynnika wzrostu oraz monoklonalnego przeciwciała przeciw CD31.WynikiWśród 75 pacjentów było 5 kobiet (6.7%) i 70 mężczyzn (93.3%) w wieku od 42 lat do 74 lat (średnio 59 lat). W badanej grupie chorych stwierdzono raka płaskonabłonkowego u 53 pacjentów (70.7%), gruczolakoraka u 11 chorych (14.7%) i raka wielkokomórkowego także u 11 pacjentów. Analizując uzyskane dane nie stwierdzono istotności statystycznej między ekspresją EGFR i czasem przeżycia pacjentów. Również GNK nie miała istotnego wpływu na przeżycie pacjentów. Jedynie stan węzłów chłonnych (cecha N; p<0.05), typ histologiczny raka (p<0.001) oraz wiek (p<0.05) w badanej grupie chorych miały istotny statystycznie wpływ na czas przeżycia.WnioskiUzyskane w tym badaniu wyniki nie są zgodne z wynikami innych doniesień mówiących o tym, że ekspresja EGFR i GNK w NRP mogą być traktowane jako czynniki prognostyczne. Należy jednak podkreślić, że analizowana grupa pacjentów była mała, a większość chorych (59 pacjentów, 78.7%) znajdowała się w stadium znacznego zaawansowania nowotworu
A versatile panel of reference gene assays for the measurement of chicken mRNA by quantitative PCR
Quantitative real-time PCR assays are widely used for the quantification of mRNA within avian experimental samples. Multiple stably-expressed reference genes, selected for the lowest variation in representative samples, can be used to control random technical variation. Reference gene assays must be reliable, have high amplification specificity and efficiency, and not produce signals from contaminating DNA. Whilst recent research papers identify specific genes that are stable in particular tissues and experimental treatments, here we describe a panel of ten avian gene primer and probe sets that can be used to identify suitable reference genes in many experimental contexts. The panel was tested with TaqMan and SYBR Green systems in two experimental scenarios: a tissue collection and virus infection of cultured fibroblasts. GeNorm and NormFinder algorithms were able to select appropriate reference gene sets in each case. We show the effects of using the selected genes on the detection of statistically significant differences in expression. The results are compared with those obtained using 28s ribosomal RNA, the present most widely accepted reference gene in chicken work, identifying circumstances where its use might provide misleading results. Methods for eliminating DNA contamination of RNA reduced, but did not completely remove, detectable DNA. We therefore attached special importance to testing each qPCR assay for absence of signal using DNA template. The assays and analyses developed here provide a useful resource for selecting reference genes for investigations of avian biology
The Large Array Survey Telescope -- System Overview and Performances
The Large Array Survey Telescope (LAST) is a wide-field visible-light
telescope array designed to explore the variable and transient sky with a high
cadence. LAST will be composed of 48, 28-cm f/2.2 telescopes (32 already
installed) equipped with full-frame backside-illuminated cooled CMOS detectors.
Each telescope provides a field of view (FoV) of 7.4 deg^2 with 1.25
arcsec/pix, while the system FoV is 355 deg^2 in 2.9 Gpix. The total collecting
area of LAST, with 48 telescopes, is equivalent to a 1.9-m telescope. The
cost-effectiveness of the system (i.e., probed volume of space per unit time
per unit cost) is about an order of magnitude higher than most existing and
under-construction sky surveys. The telescopes are mounted on 12 separate
mounts, each carrying four telescopes. This provides significant flexibility in
operating the system. The first LAST system is under construction in the
Israeli Negev Desert, with 32 telescopes already deployed. We present the
system overview and performances based on the system commissioning data. The Bp
5-sigma limiting magnitude of a single 28-cm telescope is about 19.6 (21.0), in
20 s (20x20 s). Astrometric two-axes precision (rms) at the bright-end is about
60 (30)\,mas in 20\,s (20x20 s), while absolute photometric calibration,
relative to GAIA, provides ~10 millimag accuracy. Relative photometric
precision, in a single 20 s (320 s) image, at the bright-end measured over a
time scale of about 60 min is about 3 (1) millimag. We discuss the system
science goals, data pipelines, and the observatory control system in companion
publications.Comment: Submitted to PASP, 15p
Very-high-energy γ -Ray Emission from Young Massive Star Clusters in the Large Magellanic Cloud
The Tarantula Nebula in the Large Magellanic Cloud is known for its high star formation activity. At its center lies the young massive star cluster R136, providing a significant amount of the energy that makes the nebula shine so brightly at many wavelengths. Recently, young massive star clusters have been suggested to also efficiently produce very high-energy cosmic rays, potentially beyond PeV energies. Here, we report the detection of very-high-energy γ-ray emission from the direction of R136 with the High Energy Stereoscopic System, achieved through a multicomponent, likelihood-based modeling of the data. This supports the hypothesis that R136 is indeed a very powerful cosmic-ray accelerator. Moreover, from the same analysis, we provide an updated measurement of the γ-ray emission from 30 Dor C, the only superbubble detected at TeV energies presently. The γ-ray luminosity above 0.5 TeV of both sources is (2–3) × 1035 erg s−1. This exceeds by more than a factor of 2 the luminosity of HESS J1646−458, which is associated with the most massive young star cluster in the Milky Way, Westerlund 1. Furthermore, the γ-ray emission from each source is extended with a significance of >3σ and a Gaussian width of about 30 pc. For 30 Dor C, a connection between the γ-ray emission and the nonthermal X-ray emission appears likely. Different interpretations of the γ-ray signal from R136 are discussed
The Vanishing of the Primary Emission Region in PKS 1510-089
In 2021 July, PKS 1510-089 exhibited a significant flux drop in the high-energy γ-ray (by a factor 10) and optical (by a factor 5) bands and remained in this low state throughout 2022. Similarly, the optical polarization in the source vanished, resulting in the optical spectrum being fully explained through the steady flux of the accretion disk and the broad-line region. Unlike the aforementioned bands, the very-high-energy γ-ray and X-ray fluxes did not exhibit a significant flux drop from year to year. This suggests that the steady-state very-high-energy γ-ray and X-ray fluxes originate from a different emission region than the vanished parts of the high-energy γ-ray and optical jet fluxes. The latter component has disappeared through either a swing of the jet away from the line of sight or a significant drop in the photon production efficiency of the jet close to the black hole. Either change could become visible in high-resolution radio images
COMAP Early Science: III. CO Data Processing
We describe the first season COMAP analysis pipeline that converts raw
detector readouts to calibrated sky maps. This pipeline implements four main
steps: gain calibration, filtering, data selection, and map-making. Absolute
gain calibration relies on a combination of instrumental and astrophysical
sources, while relative gain calibration exploits real-time total-power
variations. High efficiency filtering is achieved through spectroscopic
common-mode rejection within and across receivers, resulting in nearly
uncorrelated white noise within single-frequency channels. Consequently,
near-optimal but biased maps are produced by binning the filtered time stream
into pixelized maps; the corresponding signal bias transfer function is
estimated through simulations. Data selection is performed automatically
through a series of goodness-of-fit statistics, including and
multi-scale correlation tests. Applying this pipeline to the first-season COMAP
data, we produce a dataset with very low levels of correlated noise. We find
that one of our two scanning strategies (the Lissajous type) is sensitive to
residual instrumental systematics. As a result, we no longer use this type of
scan and exclude data taken this way from our Season 1 power spectrum
estimates. We perform a careful analysis of our data processing and observing
efficiencies and take account of planned improvements to estimate our future
performance. Power spectrum results derived from the first-season COMAP maps
are presented and discussed in companion papers.Comment: Paper 3 of 7 in series. 26 pages, 23 figures, submitted to Ap
COMAP Early Science: IV. Power Spectrum Methodology and Results
We present the power spectrum methodology used for the first-season COMAP
analysis, and assess the quality of the current data set. The main results are
derived through the Feed-feed Pseudo-Cross-Spectrum (FPXS) method, which is a
robust estimator with respect to both noise modeling errors and experimental
systematics. We use effective transfer functions to take into account the
effects of instrumental beam smoothing and various filter operations applied
during the low-level data processing. The power spectra estimated in this way
have allowed us to identify a systematic error associated with one of our two
scanning strategies, believed to be due to residual ground or atmospheric
contamination. We omit these data from our analysis and no longer use this
scanning technique for observations. We present the power spectra from our
first season of observing and demonstrate that the uncertainties are
integrating as expected for uncorrelated noise, with any residual systematics
suppressed to a level below the noise. Using the FPXS method, and combining
data on scales we estimate , the first direct 3D
constraint on the clustering component of the CO(1-0) power spectrum in the
literature.Comment: Paper 4 of 7 in series. 18 pages, 11 figures, as accepted in Ap
COMAP Early Science: V. Constraints and Forecasts at
We present the current state of models for the carbon monoxide (CO)
line-intensity signal targeted by the CO Mapping Array Project (COMAP)
Pathfinder in the context of its early science results. Our fiducial model,
relating dark matter halo properties to CO luminosities, informs parameter
priors with empirical models of the galaxy-halo connection and previous CO(1-0)
observations. The Pathfinder early science data spanning wavenumbers
-Mpc represent the first direct 3D constraint on the
clustering component of the CO(1-0) power spectrum. Our 95% upper limit on the
redshift-space clustering amplitude K greatly
improves on the indirect upper limit of K reported from the CO
Power Spectrum Survey (COPSS) measurement at Mpc. The COMAP
limit excludes a subset of models from previous literature, and constrains
interpretation of the COPSS results, demonstrating the complementary nature of
COMAP and interferometric CO surveys. Using line bias expectations from our
priors, we also constrain the squared mean line intensity-bias product,
K, and the cosmic molecular gas
density, Mpc (95% upper
limits). Based on early instrument performance and our current CO signal
estimates, we forecast that the five-year Pathfinder campaign will detect the
CO power spectrum with overall signal-to-noise of 9-17. Between then and now,
we also expect to detect the CO-galaxy cross-spectrum using overlapping galaxy
survey data, enabling enhanced inferences of cosmic star-formation and
galaxy-evolution history.Comment: Paper 5 of 7 in series. 17 pages + appendix and bibliography (30
pages total); 15 figures, 6 tables; accepted for publication in ApJ; v3
reflects the accepted version with minor changes and additions to tex
New trends in the economic systems management in the context of modern global challenges
New trends in the economic systems management in the context of modern global challenges: collective monograph / scientific edited by M. Bezpartochnyi, in 2 Vol. // VUZF University of Finance, Business and Entrepreneurship. – Sofia: VUZF Publishing House “St. Grigorii Bogoslov”, 2020. – Vol. 1. – 309 p
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