264 research outputs found

    Measuring galaxy cluster masses with CMB lensing using a Maximum Likelihood estimator: Statistical and systematic error budgets for future experiments

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    We develop a Maximum Likelihood estimator (MLE) to measure the masses of galaxy clusters through the impact of gravitational lensing on the temperature and polarization anisotropies of the cosmic microwave background (CMB). We show that, at low noise levels in temperature, this optimal estimator outperforms the standard quadratic estimator by a factor of two. For polarization, we show that the Stokes Q/U maps can be used instead of the traditional E- and B-mode maps without losing information. We test and quantify the bias in the recovered lensing mass for a comprehensive list of potential systematic errors. Using realistic simulations, we examine the cluster mass uncertainties from CMB-cluster lensing as a function of an experiment's beam size and noise level. We predict the cluster mass uncertainties will be 3 - 6% for SPT-3G, AdvACT, and Simons Array experiments with 10,000 clusters and less than 1% for the CMB-S4 experiment with a sample containing 100,000 clusters. The mass constraints from CMB polarization are very sensitive to the experimental beam size and map noise level: for a factor of three reduction in either the beam size or noise level, the lensing signal-to-noise improves by roughly a factor of two.Comment: 28 pages, 5 figures: figs 2, 3 updated, references added: accepted for publication in JCA

    Compaction control and related stress–strain behaviour of off-shore land reclamations with calcareous sands

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    AbstractWhen constructing off-shore land reclamations, one aims to ensure that the final soil mass fulfills certain minimal criteria related to shear strength, stiffness and resistance against liquefaction. In general, these characteristics improve with increasing density of the soil mass, which means that the above criteria are usually condensed into a single one: ‘adequate densification’.Quality control of reclamation constructions therefore focuses on the latter. Technical requirements are written based on one single parameter: the relative density Dr. On the site, this parameter is commonly determined indirectly using correlations with the cone penetration resistance qc, making the CPT the main tool for quality control.The paper presents data gathered during the design and construction of an off-shore land reclamation using calcareous sands. For this specific project, density control had to be done through the use of CPT.Calibration chamber tests were performed to establish the CPT qc–Dr correlation for the specific soil material. This correlation was used to analyse CPT results during construction of the site in order to determine the quality of compaction.In a further stage, an elaborate laboratory study was performed to establish additional correlations between soil parameters and the stress–strain parameters. Furthermore, seismic CPT tests were executed on the site to test the relevance of the laboratory correlations and the ‘relative density approach’ in general.It is shown that off-shore land reclamations have a very erratic stress-history, due to the different processes of depositing the soil material and the various densification methods. This stress-history is of great importance in the stress–strain behaviour of the site. Results also suggest that the CPT does not provide enough data to reliably predict soil stiffness when dealing with crushable materials. Specifically, in situ measurements show that there is no direct correlation between the small strain shear modulus G0 and qc

    Cucurbit[n]uril binding of platinum anticancer complexes

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    The encapsulation of cisplatin by cucurbit[7]uril (Q[7]) and multinuclear platinum complexes linked via a 4,4â€Č-dipyrazolylmethane (dpzm) ligand by Q[7] and cucurbit[8]uril (Q[8]) has been studied by NMR spectroscopy and molecular modelling. The NMR studies suggest that some cisplatin binds in the cucurbituril cavity, while cis-[PtCl(NH3)2(H2O)]+ only binds at the portals. Alternatively, the dpzm-linked multinuclear platinum complexes are quantitatively encapsulated within the cavities of both Q[7] and Q[8]. Upon encapsulation, the non-exchangeable proton resonances of the multinuclear platinum complexes show significant upfield shifts in 1H NMR spectra. The H3/H3* resonances shift upfield by 0.08 to 0.55 ppm, the H5/H5* shift by 0.9 to 1.6 ppm, while the methylene resonances shift by 0.74 to 0.88 ppm. The size of the resonance shift is dependent on the cavity size of the encapsulating cucurbituril, with Q[7] encapsulation producing larger shifts than Q[8]. The upfield shifts of the dpzm resonances observed upon cucurbituril encapsulation indicate that the Q[7] or Q[8] is positioned directly over the dpzm linking ligand. The terminal platinum groups of trans-[{PtCl(NH3)2}2ÎŒ-dpzm]2+ (di-Pt) and trans-[trans-{PtCl(NH3)2}2-trans-{Pt(dpzm)2(NH3)2}]4+ (tri-Pt) provide a barrier to the on and off movement of cucurbituril, resulting in binding kinetics that are slow on the NMR timescale for the metal complex. Although the dpzm ligand has relatively few rotamers, encapsulation by the larger Q[8] resulted in a more compact di-Pt conformation with each platinum centre retracted further into each Q[8] portal. Encapsulation of the hydrolysed forms of di-Pt and tri-Pt is considerably slower than for the corresponding Cl forms, presumably due to the high-energy cost of passing the +2 platinum centres through the cucurbituril portals. The results of this study suggest that cucurbiturils could be suitable hosts for the pharmacological delivery of multinuclear platinum complexe

    Neorealism: unifying cognition and environment

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    APA ProofsRecent trends in psychology have revealed increasing discontent toward representational explanations of behavior. However, whether these trends have the conceptual resources to address the full range of cognitive phenomena remains unclear. Here, I defend neorealism (Holt, 1914) as the missing philosophical link between radically embodied cognitive science and a more encompassing psychology. Neorealism identifies cognitive contents, however subjective or unreal in appearance, with portions or cross sections of the objective environment. These portions are extended in time and they sustain causal and historical relations to current behavior. I sketch how neorealist concepts can help psychologists to address phenomena such as dreams and imagery in fully environmental terms

    The novel lncRNA BlackMamba controls the neoplastic phenotype of ALK- anaplastic large cell lymphoma by regulating the DNA helicase HELLS.

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    The molecular mechanisms leading to the transformation of anaplastic lymphoma kinase negative (ALK-) anaplastic large cell lymphoma (ALCL) have been only in part elucidated. To identify new culprits which promote and drive ALCL, we performed a total transcriptome sequencing and discovered 1208 previously unknown intergenic long noncoding RNAs (lncRNAs), including 18 lncRNAs preferentially expressed in ALCL. We selected an unknown lncRNA, BlackMamba, with an ALK- ALCL preferential expression, for molecular and functional studies. BlackMamba is a chromatin-associated lncRNA regulated by STAT3 via a canonical transcriptional signaling pathway. Knockdown experiments demonstrated that BlackMamba contributes to the pathogenesis of ALCL regulating cell growth and cell morphology. Mechanistically, BlackMamba interacts with the DNA helicase HELLS controlling its recruitment to the promoter regions of cell-architecture-related genes, fostering their expression. Collectively, these findings provide evidence of a previously unknown tumorigenic role of STAT3 via a lncRNA-DNA helicase axis and reveal an undiscovered role for lncRNA in the maintenance of the neoplastic phenotype of ALK-ALCL

    CMB Polarization B-mode Delensing with SPTpol and Herschel

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    We present a demonstration of delensing the observed cosmic microwave background (CMB) B-mode polarization anisotropy. This process of reducing the gravitational-lensing generated B-mode component will become increasingly important for improving searches for the B modes produced by primordial gravitational waves. In this work, we delens B-mode maps constructed from multi-frequency SPTpol observations of a 90 deg2^2 patch of sky by subtracting a B-mode template constructed from two inputs: SPTpol E-mode maps and a lensing potential map estimated from the Herschel\textit{Herschel} 500 Όm500\,\mu m map of the CIB. We find that our delensing procedure reduces the measured B-mode power spectrum by 28% in the multipole range 300<ℓ<2300300 < \ell < 2300; this is shown to be consistent with expectations from theory and simulations and to be robust against systematics. The null hypothesis of no delensing is rejected at 6.9σ6.9 \sigma. Furthermore, we build and use a suite of realistic simulations to study the general properties of the delensing process and find that the delensing efficiency achieved in this work is limited primarily by the noise in the lensing potential map. We demonstrate the importance of including realistic experimental non-idealities in the delensing forecasts used to inform instrument and survey-strategy planning of upcoming lower-noise experiments, such as CMB-S4.Comment: 17 pages, 10 figures. Comments are welcome

    Measurements of the Temperature and E-Mode Polarization of the CMB from 500 Square Degrees of SPTpol Data

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    We present measurements of the EE-mode polarization angular auto-power spectrum (EEEE) and temperature-EE-mode cross-power spectrum (TETE) of the cosmic microwave background (CMB) using 150 GHz data from three seasons of SPTpol observations. We report the power spectra over the spherical harmonic multipole range 50<ℓ≀800050 < \ell \leq 8000, and detect nine acoustic peaks in the EEEE spectrum with high signal-to-noise ratio. These measurements are the most sensitive to date of the EEEE and TETE power spectra at ℓ>1050\ell > 1050 and ℓ>1475\ell > 1475, respectively. The observations cover 500 deg2^2, a fivefold increase in area compared to previous SPTpol analyses, which increases our sensitivity to the photon diffusion damping tail of the CMB power spectra enabling tighter constraints on \LCDM model extensions. After masking all sources with unpolarized flux >50>50 mJy we place a 95% confidence upper limit on residual polarized point-source power of Dℓ=ℓ(ℓ+1)Cℓ/2π<0.107 ΌK2D_\ell = \ell(\ell+1)C_\ell/2\pi <0.107\,\mu{\rm K}^2 at ℓ=3000\ell=3000, suggesting that the EEEE damping tail dominates foregrounds to at least ℓ=4050\ell = 4050 with modest source masking. We find that the SPTpol dataset is in mild tension with the ΛCDM\Lambda CDM model (2.1 σ2.1\,\sigma), and different data splits prefer parameter values that differ at the ∌1 σ\sim 1\,\sigma level. When fitting SPTpol data at ℓ<1000\ell < 1000 we find cosmological parameter constraints consistent with those for PlanckPlanck temperature. Including SPTpol data at ℓ>1000\ell > 1000 results in a preference for a higher value of the expansion rate (H_0 = 71.3 \pm 2.1\,\mbox{km}\,s^{-1}\mbox{Mpc}^{-1} ) and a lower value for present-day density fluctuations (σ8=0.77±0.02\sigma_8 = 0.77 \pm 0.02).Comment: Updated to match version accepted to ApJ. 34 pages, 17 figures, 6 table

    Permian high-temperature metamorphism in the Western Alps (NW Italy)

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    During the late Palaeozoic, lithospheric thinning in part of the Alpine realm caused high-temperature low-to-medium pressure metamorphism and partial melting in the lower crust. Permian metamorphism and magmatism has extensively been recorded and dated in the Central, Eastern, and Southern Alps. However, Permian metamorphic ages in the Western Alps so far are constrained by very few and sparsely distributed data. The present study fills this gap. We present U/Pb ages of metamorphic zircon from several Adria-derived continental units now situated in the Western Alps, defining a range between 286 and 266 Ma. Trace element thermometry yields temperatures of 580-890°C from Ti-in-zircon and 630-850°C from Zr-in-rutile for Permian metamorphic rims. These temperature estimates, together with preserved mineral assemblages (garnet-prismatic sillimanite-biotite-plagioclase-quartz-K-feldspar-rutile), define pervasive upper-amphibolite to granulite facies conditions for Permian metamorphism. U/Pb ages from this study are similar to Permian ages reported for the Ivrea Zone in the Southern Alps and Austroalpine units in the Central and Eastern Alps. Regional comparison across the former Adriatic and European margin reveals a complex pattern of ages reported from late Palaeozoic magmatic and metamorphic rocks (and relics thereof): two late Variscan age groups (~330 and ~300 Ma) are followed seamlessly by a broad range of Permian ages (300-250 Ma). The former are associated with late-orogenic collapse; in samples from this study these are weakly represented. Clearly, dominant is the Permian group, which is related to crustal thinning, hinting to a possible initiation of continental rifting along a passive margin

    Synthesis and biological evaluation of dual action cyclo-RGD/SMAC mimetic conjugates targeting &#945;v&#946;3/&#945;v&#946;5 integrins and IAP proteins

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    The rational design, synthesis and in vitro biological evaluation of dual action conjugates 11-13, containing a tumour targeting, integrin a(v)beta(3)/a(v)beta(5) ligand portion and a pro-apoptotic SMAC mimetic portion (cyclo-RGD/SMAC mimetic conjugates) are reported. The binding strength of the two separate units is generally maintained by these dual action conjugates. In particular, the connection between the separate units (anchor points on each unit; nature, length and stability of the linker) influences the activity of each portion against its molecular targets (integrins a(v)beta(3)/a(v)beta(5) for cyclo-RGD, IAP proteins for SMAC mimetics). Each conjugate portion tolerates different substitutions while preserving the binding affinity for each target

    The p53 Codon 72 Pro/Pro Genotype Identifies Poor-Prognosis Neuroblastoma Patients: Correlation with Reduced Apoptosis and Enhanced Senescence by the p53-72P Isoform.

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    The p53 gene is rarely mutated in neuroblastoma, but codon 72 polymorphism that modulates its proapoptotic activity might influence cancer risk and clinical outcome. We investigated whether this polymorphism affects neuroblastoma risk and disease outcome and assessed the biologic effects of the p53-72R and p53-72P isoforms in p53-null cells. Comparison of 288 healthy subjects and 286 neuroblastoma patients revealed that the p53-72 polymorphism had no significant impact on the risk of developing neuroblastoma; however, patients with the Pro/Pro genotype had a shorter survival than those with the Arg/Arg or the Arg/Pro genotypes even in the stage 3 and 4 subgroup without MYCN amplification. By Cox regression analysis, the p53 Pro/Pro genotype seems to be an independent marker of poor prognosis (hazard ratio = 2.74; 95% confidence interval = 1.14\u20136.55, P = .014) together with clinical stage, MYCN status, and age at diagnosis. In vitro, p53-72P was less effective than p53-72R in inducing apoptosis and inhibiting survival of p53-null LAN-1 cells treated with etoposide, topotecan, or ionizing radiation but not taxol. By contrast, p53-72P was more effective in promoting p21-dependent accelerated senescence, alone or in the presence of etoposide. Thus, the p53-72 Pro/Pro genotype might be a marker of poor outcome independent of MYCN amplification, possibly improving risk stratification. Moreover, the lower apoptosis and the enhanced accelerated senescence by the p53-72P isoform in response to DNA damage suggest that patients with neuroblastoma with the p53-72 Pro/Pro genotype may benefit from therapeutic protocols that do not rely only on cytotoxic drugs that function, in part, through p53 activation
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