222 research outputs found
Notes on counter-orbiting globular clusters in the Milky Way
It is argued that Galactic globular clusters rotating retrograde may originate from prograde globular clusters that change their angular momenturm due to gravitational perturbations from the Magellanic Cloud galaxies. It is shown that those galactic globular clusters with orbits near the Lagrangiane point of the system "Milky Way - Maggellanic Clouds" can change the sign of their angular momentum in few Gyr time scale
Cosmological information in the redshift-space bispectrum
We use the Fisher-matrix formalism to investigate whether the galaxy bispectrum in redshift space, B, contains additional cosmological information with respect to the power spectrum, P. We focus on a Euclid-like survey and consider cosmological models dominated by dark energy and cold dark matter with Gaussian primordial perturbations. After discussing the phenomenology of redshift-space distortions for the bispectrum, we derive an expression for the cross-covariance between B and P at leading order in perturbation theory. Our equation generalizes previous results that did not consider binning in the orientation of wavevector triangles with respect to the line of sight. By considering Fourier modes with wavenumbe
ΠΠΏΡΠ΅Π΄Π΅Π»Π΅Π½ΠΈΠ΅ ΠΊΠΎΠΎΡΠ΄ΠΈΠ½Π°Ρ ΠΏΠΎΠ»ΡΠ·ΠΎΠ²Π°ΡΠ΅Π»Ρ Π² ΡΠΏΡΡΠ½ΠΈΠΊΠΎΠ²ΡΡ Π½Π°Π²ΠΈΠ³Π°ΡΠΈΠΎΠ½Π½ΡΡ ΡΠΈΡΡΠ΅ΠΌΠ°Ρ
ΠΠ°ΠΏΡΠΎΠΏΠΎΠ½ΠΎΠ²Π°Π½ΠΎ ΡΠΈΡΡΠ΅ΠΌΡ Π»ΡΠ½ΡΠΉΠ½ΠΈΡ
Π°Π»Π³Π΅Π±ΡΠ°ΡΡΠ½ΠΈΡ
ΡΡΠ²Π½ΡΠ½Ρ Π·Π° Π΄ΠΎΠΏΠΎΠΌΠΎΠ³ΠΎΡ ΡΠΊΠΎΡ ΠΌΠΎΠΆΠ½Π° Π²ΠΈΠ·Π½Π°ΡΠ°ΡΠΈ ΠΊΠΎΠΎΡΠ΄ΠΈΠ½Π°ΡΠΈ ΠΊΠΎΡΠΈΡΡΡΠ²Π°ΡΠ° ΡΠ° ΠΏΠΎΠΏΡΠ°Π²ΠΊΡ ΡΡΠ·Π½ΠΈΡΡ ΡΠ°ΡΡΠ² Π³ΠΎΠ΄ΠΈΠ½Π½ΠΈΠΊΡΠ² ΡΡΠΏΡΡΠ½ΠΈΠΊΠ° ΡΠ° ΠΊΠΎΡΠΈΡΡΡΠ²Π°ΡΠ° Π² ΡΡΠΏΡΡΠ½ΠΈΠΊΠΎΠ²ΠΈΡ
Π½Π°Π²ΡΠ³Π°ΡΡΠΉΠ½ΠΈΡ
ΡΠΈΡΡΠ΅ΠΌΠ°Ρ
.In satellite navigation systems (SNS) the userβs and satellitesβ coordinates and the difference between the satellite and the user clocks are connected by the system of nonlinear equations of pseudo-distances between satellites and the user. The usage of these equations in calculations is not convenient. Therefore, for calculation of the userβs coordinates and the difference between clocks in SNS the linearized by Taylor series expansion and rejection of members of the second order of smallness equations are used. Thus the calculation of these variables is carried out by iterations. By algebraic manipulations it is possible to transform the system of nonlinear equations of pseudo-distances between satellites and the user into a system of linear equations about the coordinates of the user and the difference between the satellitesβ and the userβs clocks. Application of the method of iteration is not required. Therefore, the application of such a system of linear equations will reduce the number and the count of these variables.ΠΡΠ΅Π΄Π»ΠΎΠΆΠ΅Π½Π° ΡΠΈΡΡΠ΅ΠΌΠ° Π»ΠΈΠ½Π΅ΠΉΠ½ΡΡ
Π°Π»Π³Π΅Π±ΡΠ°ΠΈΡΠ΅ΡΠΊΠΈΡ
ΡΡΠ°Π²Π½Π΅Π½ΠΈΠΉ Ρ ΠΏΠΎΠΌΠΎΡΡΡ ΠΊΠΎΡΠΎΡΠΎΠΉ ΠΌΠΎΠΆΠ½Π° ΠΎΠΏΡΠ΅Π΄Π΅Π»ΡΡΡ ΠΊΠΎΠΎΡΠ΄ΠΈΠ½Π°ΡΡ ΠΏΠΎΠ»ΡΠ·ΠΎΠ²Π°ΡΠ΅Π»Ρ ΠΈ ΠΏΠΎΠΏΡΠ°Π²ΠΊΡ ΡΠ°Π·Π½ΠΎΡΡΠΈ Π²ΡΠ΅ΠΌΠ΅Π½ ΡΠ°ΡΠΎΠ² ΡΠΏΡΡΠ½ΠΈΠΊΠ° ΠΈ ΠΏΠΎΠ»ΡΠ·ΠΎΠ²Π°ΡΠ΅Π»Ρ Π² ΡΠΏΡΡΠ½ΠΈΠΊΠΎΠ²ΡΡ
Π½Π°Π²ΠΈΠ³Π°ΡΠΈΠΎΠ½Π½ΡΡ
ΡΠΈΡΡΠ΅ΠΌΠ°Ρ
The halo bispectrum as a sensitive probe of massive neutrinos an baryon physics
The power spectrum has been a workhorse for cosmological studies of large-scale structure. However, the present-day matter distribution is highly non-Gaussian and significant cosmological information is also contained in higher order correlation functions. Meanwhile, baryon physics (particularly active galactic nucleus feedback) has previously been shown to strongly affect the two-point statistics but there has been limited exploration of its effects on higher order functions to date. Here, we use the BAHAMAS suite of cosmological hydrodynamical simulations to explore the effects of baryon physics and massive neutrinos on the halo bispectrum. In contrast to matter clustering which is suppressed by baryon physics, we find that the halo clustering is typically enhanced. The strength of the effect and the scale over which it extends depends on how haloes are selected. On small scales (β kβ³1 h Mpcβ1, dominated by satellites of groups/clusters), we find that the bispectrum is highly sensitive to the efficiency of star formation and feedback, making it an excellent testing ground for galaxy formation models. We show that the effects of feedback and the effects of massive neutrinos are largely separable (independent of each other) and that massive neutrinos strongly suppress the halo bispectrum on virtually all scales up to the free-streaming length (apart from the smallest scales, where baryon physics dominates). The strong sensitivity of the bispectrum to neutrinos on the largest scales and galaxy formation physics on the smallest scales bodes well for upcoming precision measurements from the next generation of wide-field surveys
ΠΠ½Π°Π»ΠΈΠ· ΠΈΠ½ΡΡΡΡΠΌΠ΅Π½ΡΠ°Π»ΡΠ½ΡΡ ΠΏΠΎΠ³ΡΠ΅ΡΠ½ΠΎΡΡΠ΅ΠΉ ΠΌΠΎΡΡΠΎΠ²ΠΎΠ³ΠΎ ΠΊΠΎΠΌΠΌΡΡΠ°ΡΠΎΡΠ° ΡΠΈΡΠΎΡΠ½ΠΎ-ΠΈΠΌΠΏΡΠ»ΡΡΠ½ΠΎΠ³ΠΎ ΠΌΠΎΠ΄ΡΠ»ΡΡΠΎΡΠ° ΡΠΎΠΊΠ°
Π ΠΎΠ·Π³Π»ΡΠ½ΡΡΠΎ ΡΠ½ΡΡΡΡΠΌΠ΅Π½ΡΠ°Π»ΡΠ½Ρ ΠΏΠΎΡ
ΠΈΠ±ΠΊΠΈ Π΅Π»Π΅ΠΊΡΡΠΎΠ½Π½ΠΎΠ³ΠΎ ΠΏΡΠ΅ΡΠΈΠ·ΡΠΉΠ½ΠΎΠ³ΠΎ ΠΌΠΎΡΡΠΎΠ²ΠΎΠ³ΠΎ ΠΊΠΎΠΌΡΡΠ°ΡΠΎΡΠ° ΡΠ· ΡΡΠ°Π±ΡΠ»ΡΠ·Π°ΡΡΡΡ ΡΡΡΡΠΌΡ, ΠΊΠΎΡΡΠΈΠΉ Π²ΠΈΠΊΠΎΡΠΈΡΡΠΎΠ²ΡΡΡΡΡΡ Π² ΡΠΈΡΠΎΡΠ½ΠΎ-ΡΠΌΠΏΡΠ»ΡΡΠ½ΠΈΡ
ΠΌΠΎΠ΄ΡΠ»ΡΡΠΎΡΠ°Ρ
. ΠΡΠΈΠ²Π΅Π΄Π΅Π½ΠΎ Π²ΠΈΡΠ°Π· Π΄Π»Ρ ΠΎΡΡΠ½ΠΊΠΈ Π²ΠΊΠ°Π·Π°Π½ΠΈΡ
ΠΏΠΎΡ
ΠΈΠ±ΠΎΠΊ, ΡΠΊΡ Π½Π°Π΄Π°ΡΡΡ ΡΠ°ΠΊΠΎΠΆ ΠΌΠΎΠΆΠ»ΠΈΠ²ΡΡΡΡ Π²ΠΈΠ·Π½Π°ΡΠΈΡΠΈ Π²ΠΈΠΌΠΎΠ³ΠΈ Π΄ΠΎ ΠΏΠΎΡ
ΠΈΠ±ΠΎΠΊ ΠΏΠ°ΡΠ°ΠΌΠ΅ΡΡΡΠ² Π΅Π»Π΅ΠΊΡΡΠΎΠ½Π½ΠΈΡ
ΠΊΠΎΠΌΠΏΠΎΠ½Π΅Π½ΡΡΠ² ΠΊΠΎΠΌΡΡΠ°ΡΠΎΡΠ°.There are considered instrumental errors of electronic, precision bridge switcher with current stabilization, which is used in width-pulse modulators. There is made an expression for specified errors estimation, which is giving also a possibility to determine requirements parameter errors of electronic switcherβs components.Π Π°ΡΡΠΌΠΎΡΡΠ΅Π½Ρ ΠΈΠ½ΡΡΡΡΠΌΠ΅Π½ΡΠ°Π»ΡΠ½ΡΠ΅ ΠΏΠΎΠ³ΡΠ΅ΡΠ½ΠΎΡΡΠΈ ΡΠ»Π΅ΠΊΡΡΠΎΠ½Π½ΠΎΠ³ΠΎ, ΠΏΡΠ΅ΡΠΈΠ·ΠΈΠΎΠ½Π½ΠΎΠ³ΠΎ, ΠΌΠΎΡΡΠΎΠ²ΠΎΠ³ΠΎ ΠΊΠΎΠΌΠΌΡΡΠ°ΡΠΎΡΠ° ΡΠΎ ΡΡΠ°Π±ΠΈΠ»ΠΈΠ·Π°ΡΠΈΠ΅ΠΉ ΡΠΎΠΊΠ°, ΠΊΠΎΡΠΎΡΡΠΉ ΠΈΡΠΏΠΎΠ»ΡΠ·ΡΠ΅ΡΡΡ Π² ΡΠΈΡΠΎΡΠ½ΠΎ-ΠΈΠΌΠΏΡΠ»ΡΡΠ½ΡΡ
ΠΌΠΎΠ΄ΡΠ»ΡΡΠΎΡΠ°Ρ
. ΠΡΠΈΠ²Π΅Π΄Π΅Π½ΠΎ Π²ΡΡΠ°ΠΆΠ΅Π½ΠΈΠ΅ Π΄Π»Ρ ΠΎΡΠ΅Π½ΠΊΠΈ ΡΠΊΠ°Π·Π°Π½Π½ΡΡ
ΠΏΠΎΠ³ΡΠ΅ΡΠ½ΠΎΡΡΠ΅ΠΉ, Π΄Π°ΡΡΠ΅Π΅ ΡΠ°ΠΊΠΆΠ΅ Π²ΠΎΠ·ΠΌΠΎΠΆΠ½ΠΎΡΡΡ ΠΎΠΏΡΠ΅Π΄Π΅Π»ΠΈΡΡ ΡΡΠ΅Π±ΠΎΠ²Π°Π½ΠΈΡ ΠΊ ΠΏΠΎΠ³ΡΠ΅ΡΠ½ΠΎΡΡΡΠΌ ΠΏΠ°ΡΠ°ΠΌΠ΅ΡΡΠΎΠ² ΡΠ»Π΅ΠΊΡΡΠΎΠ½Π½ΡΡ
ΠΊΠΎΠΌΠΏΠΎΠ½Π΅Π½ΡΠΎΠ² ΠΊΠΎΠΌΠΌΡΡΠ°ΡΠΎΡΠ°
Neurology
Contains reports on eight research projects.U.S. Navy (Office of Naval Research (Nonr-1841(70))U. S. Public Health Service (MH-06175-02)U. S. Air Force (AF49(638)-1313)U. S. Public Health Service (B-3055-4)U. S. Public Health Service (B-3090-4
Targeting and killing of glioblastoma with activated T cells armed with bispecific antibodies
Abstract
Background
Since most glioblastomas express both wild-type EGFR and EGFRvIII as well as HER2/neu, they are excellent targets for activated T cells (ATC) armed with bispecific antibodies (BiAbs) that target EGFR and HER2.
Methods
ATC were generated from PBMC activated for 14βdays with anti-CD3 monoclonal antibody in the presence of interleukin-2 and armed with chemically heteroconjugated anti-CD3Γanti-HER2/neu (HER2Bi) and/or anti-CD3Γanti-EGFR (EGFRBi). HER2Bi- and/or EGFRBi-armed ATC were examined for in vitro cytotoxicity using MTT and 51Cr-release assays against malignant glioma lines (U87MG, U118MG, and U251MG) and primary glioblastoma lines.
Results
EGFRBi-armed ATC killed up to 85% of U87, U118, and U251 targets at effector:target ratios (E:T) ranging from 1:1 to 25:1. Engagement of tumor by EGFRBi-armed ATC induced Th1 and Th2 cytokine secretion by armed ATC. HER2Bi-armed ATC exhibited comparable cytotoxicity against U118 and U251, but did not kill HER2-negative U87 cells. HER2Bi- or EGFRBi-armed ATC exhibited 50β80% cytotoxicity against four primary glioblastoma lines as well as a temozolomide (TMZ)-resistant variant of U251. Both CD133β and CD133+ subpopulations were killed by armed ATC. Targeting both HER2Bi and EGFRBi simultaneously showed enhanced efficacy than arming with a single BiAb. Armed ATC maintained effectiveness after irradiation and in the presence of TMZ at a therapeutic concentration and were capable of killing multiple targets.
Conclusion
High-grade gliomas are suitable for specific targeting by armed ATC. These data, together with additional animal studies, may provide the preclinical support for the use of armed ATC as a valuable addition to current treatment regimens
Euclid: Forecasts for k-cut 3Γ2 Point Statistics
Modelling uncertainties at small scales, i.e. high k in the power spectrum P(k), due to baryonic feedback, nonlinear structure growth and the fact that galaxies are biased tracers poses a significant obstacle to fully leverage the constraining power of the Euclid wide-field survey. k-cut cosmic shear has recently been proposed as a method to optimally remove sensitivity to these scales while preserving usable information. In this paper we generalise the k-cut cosmic shear formalism to 3Γ2 point statistics and estimate the loss of information for different k-cuts in a 3Γ2 point analysis of the Euclid data. Extending the Fisher matrix analysis of Euclid Collaboration: Blanchard et al. (2019), we assess the degradation in constraining power for different k-cuts. We find that taking a k-cut at 2.6 h Mpcβ»ΒΉ yields a dark energy Figure of Merit (FOM) of 1018. This is comparable to taking a weak lensing cut at β=5000 and a galaxy clustering and galaxy-galaxy lensing cut at β=3000 in a traditional 3Γ2 point analysis. We also find that the fraction of the observed galaxies used in the photometric clustering part of the analysis is one of the main drivers of the FOM. Removing 50% (90%) of the clustering galaxies decreases the FOM by 19% (62%). Given that the FOM depends so heavily on the fraction of galaxies used in the clustering analysis, extensive efforts should be made to handle the real-world systematics present when extending the analysis beyond the luminous red galaxy (LRG) sample
Euclid: The importance of galaxy clustering and weak lensing cross-correlations within the photometric Euclid survey
Context. The data from the Euclid mission will enable the measurement of the angular positions and weak lensing shapes of over a billion galaxies,
with their photometric redshifts obtained together with ground-based observations. This large dataset, with well-controlled systematic effects, will
allow for cosmological analyses using the angular clustering of galaxies (GCph) and cosmic shear (WL). For Euclid, these two cosmological probes
will not be independent because they will probe the same volume of the Universe. The cross-correlation (XC) between these probes can tighten
constraints and is therefore important to quantify their impact for Euclid.
Aims. In this study, we therefore extend the recently published Euclid forecasts by carefully quantifying the impact of XC not only on the
final parameter constraints for different cosmological models, but also on the nuisance parameters. In particular, we aim to decipher the amount
of additional information that XC can provide for parameters encoding systematic effects, such as galaxy bias, intrinsic alignments (IAs), and
knowledge of the redshift distributions.
Methods. We follow the Fisher matrix formalism and make use of previously validated codes. We also investigate a different galaxy bias model,
which was obtained from the Flagship simulation, and additional photometric-redshift uncertainties; we also elucidate the impact of including the
XC terms on constraining these latter.
Results. Starting with a baseline model, we show that the XC terms reduce the uncertainties on galaxy bias by βΌ17% and the uncertainties on IA
by a factor of about four. The XC terms also help in constraining the Ξ³ parameter for minimal modified gravity models. Concerning galaxy bias,
we observe that the role of the XC terms on the final parameter constraints is qualitatively the same irrespective of the specific galaxy-bias model
used. For IA, we show that the XC terms can help in distinguishing between different models, and that if IA terms are neglected then this can lead
to significant biases on the cosmological parameters. Finally, we show that the XC terms can lead to a better determination of the mean of the
photometric galaxy distributions.
Conclusions. We find that the XC between GCph and WL within the Euclid survey is necessary to extract the full information content from the data
in future analyses. These terms help in better constraining the cosmological model, and also lead to a better understanding of the systematic effects
that contaminate these probes. Furthermore, we find that XC significantly helps in constraining the mean of the photometric-redshift distributions,
but, at the same time, it requires more precise knowledge of this mean with respect to single probes in order not to degrade the final βfigure of
meritβ
- β¦