A search for concentric rings with unusual variance in the 7-year WMAP temperature maps using a fast convolution approach

We present a method for the computation of the variance of cosmic microwave background (CMB) temperature maps on azimuthally symmetric patches using a fast convolution approach. As an example of the application of the method, we show results for the search for concentric rings with unusual variance in the 7-year WMAP data. We re-analyse claims concerning the unusual variance profile of rings centred at two locations on the sky that have recently drawn special attention in the context of the conformal cyclic cosmology scenario proposed by Penrose (2009). We extend this analysis to rings with larger radii and centred on other points of the sky. Using the fast convolution technique enables us to perform this search with higher resolution and a wider range of radii than in previous studies. We show that for one of the two special points rings with radii larger than 10 degrees have systematically lower variance in comparison to the concordance LambdaCDM model predictions. However, we show that this deviation is caused by the multipoles up to order l=7. Therefore, the deficit of power for concentric rings with larger radii is yet another manifestation of the well-known anomalous CMB distribution on large angular scales. Furthermore, low variance rings can be easily found centred on other points in the sky. In addition, we show also the results of a search for extremely high variance rings. As for the low variance rings, some anomalies seem to be related to the anomalous distribution of the low-order multipoles of the WMAP CMB maps. As such our results are not consistent with the conformal cyclic cosmology scenario.Comment: 12 pages, 11 figures, 1 table. Published in MNRAS. This research was supported by the Agence Nationale de la Recherche (ANR-08-CEXC-0002-01

CMB temperature lensing power reconstruction

We study reconstruction of the lensing potential power spectrum from CMB temperature data, with an eye to the Planck experiment. We work with the optimal quadratic estimator of Okamoto and Hu, which we characterize thoroughly in application to reconstruction of the lensing power spectrum. We find that at multipoles L<250 our current understanding of this estimator is biased at the 15% level by beyond-gradient terms in the Taylor expansion of lensing effects. We present the full lensed trispectrum to fourth order in the lensing potential to explain this effect. We show that the low-L bias, as well as a previously known bias at high-L, is relevant to the determination of cosmology and must be corrected for in order to avoid significant parameter errors. We also investigate the covariance of the reconstructed power, finding broad correlations of ~0.1%. Finally, we discuss several small improvements which may be made to the optimal estimator to mitigate these problems.Comment: straightforward bias mitigation on pg. 14, matches version accepted by PR

Ocena wyników postępowania terapeutycznego chorych leczonych endowaskularnie z powodu tętniaka mózgu

Introduction. Intracranial aneurysm is the most common type of brain vascular defects. Their treatment is based on excluding vascular malformation from circulation. Endovascular methods are being performed more and more often.Aim. Evaluation of the results of therapeutic management of patients treated endovascularly for cerebral aneurysm.Material and Methods. The study involved 49 patients with a diagnosed brain aneurysm qualified for endovascular treatment (embolization, stent). Standardized research tools were used: GCS, H&amp;H, GOS, SWF. The examination was carried out twice on one patient: on the day of admission and discharge from the ward. The collected material was statistically processed.Results. Most of the respondents were women — 74%. Almost 61% of patients had non-cracked aneurysm. In 41% embolization was performed, and in 39% embolization with a stent. The aneurysm site was associated with the GCS score at discharge χ²(8) = 15.64; p &lt; 0.05; V = 0.40. Marital status was associated with SWF in the assessment 2: χ²(9) = 19.18; p &lt; 0.05; V = 0.36. The state of consciousness of the patients had no significant impact on the scope of their functioning: GCS Z = 0.42; p = 0.675 and SWF Z = 0.40; p = 0.689.Conclusions. The clinical condition of patients with cerebral aneurysm varies depending on the stage of treatment, admission mode and type of aneurysm. Only the professional situation and marital status of the examined persons influenced the functional state and the final assessment of patients’ treatment. (JNNN 2020;9(1):3–11)Wstęp. Tętniak tętnic wewnątrzczaszkowych to najczęstszy rodzaj wad naczyniowych mózgu. Leczenie ich opiera się na wyłączeniu malformacji naczyniowej z krążenia. Coraz częściej wykonywane są metody endowaskularne.Cel. Ocena wyników postępowania terapeutycznego chorych leczonych endowaskularnie z powodu tętniaka mózgu.Materiał i metody. W badaniach uczestniczyło 49 pacjentów z rozpoznanym tętniakiem mózgu, zakwalifikowanych do leczenia endowaskularnego (embolizacja, stent). Zastosowano standaryzowane narzędzia badawcze: GCS, H&amp;H, GOS, SWF. Badanie zostało przeprowadzone dwukrotnie u jednego pacjenta: w dniu przyjęcia i wypisu z oddziału. Zebrany materiał opracowano statystycznie.Wyniki. Większość badanych stanowiły kobiety — 74%. Tętniak niepęknięty miało 61% pacjentów. U 41% wykonano embolizację, a u 39% embolizację ze stentem. Miejsce tętniaka było powiązane z oceną GCS przy wypisie χ²(8) = 15,64; p &lt; 0,05; V = 0,40. Stan cywilny był powiązany ze SWF w ocenie 2: χ²(9) = 19,18; p &lt; 0,05; V = 0,36. Stan przytomności chorych nie miał istotnego wpływu na zakres ich funkcjonowania: GCS Z = 0,42; p = 0,675 i SWF Z = 0,40; p = 0,689.Wnioski. Stan kliniczny chorych z tętniakiem mózgu zmienia się w zależności od etapu leczenia, trybu przyjęcia i rodzaju tętniaka. Tylko sytuacja zawodowa i stan cywilny badanych osób wpływały na stan funkcjonalny i końcową ocenę leczenia pacjentów. (PNN 2020;9(1):3–11

Can one reconstruct masked CMB sky?

The CMB maps obtained by observations always possess domains which have to be masked due to severe uncertainties with respect to the genuine CMB signal. Cosmological analyses ideally use full CMB maps in order to get e.g. the angular power spectrum. There are attempts to reconstruct the masked regions at least at low resolutions, i.e. at large angular scales, before a further analysis follows. In this paper, the quality of the reconstruction is investigated for the ILC (7yr) map as well as for 1000 CMB simulations of the LambdaCDM concordance model. The latter allows an error estimation for the reconstruction algorithm which reveals some drawbacks. The analysis points to errors of the order of a significant fraction of the mean temperature fluctuation of the CMB. The temperature 2-point correlation function C(theta) is evaluated for different reconstructed sky maps which leads to the conclusion that it is safest to compute it on the cut-sky

Cross-correlation between PlanckPlanck CMB lensing potential and galaxy catalogues from HELP

We present the study of cross-correlation between Cosmic Microwave Background (CMB) gravitational lensing potential map released by the \textit{Planck} collaboration and photometric redshift galaxy catalogues from the \textit{Herschel} Extragalactic Legacy Project (HELP), divided into four sky patches: NGP, \textit{Herschel} Stripe-82, and two halves of SGP field, covering in total $\sim 660$ deg$^{2}$ of the sky. We estimate the galaxy linear bias parameter, $b_{0}$, from joint analysis of cross-power spectrum and galaxy auto-power spectrum using Maximum Likelihood Estimation technique to obtain values ranging from $0.70 \pm 0.01$ for SGP Part-2 to $1.02 \pm 0.02$ for SGP Part-1 field. We also estimate the amplitude of cross-correlation and find the values spanning from $0.67 \pm 0.18$ for SGP Part-2 to $0.80 \pm 0.23$ for SGP Part-1 field, respectively. For NGP and SGP Part-1 fields the amplitude is consistent with the expected value for the standard cosmological model within $\sim 1\,\sigma$, while for \textit{Herschel} Stripe-82 and SGP Part-2 we find the amplitude to be smaller than expected with $\sim 1.5\,\sigma$ and $\sim 2\,\sigma$ deviation, respectively. We perform several tests on various systematic errors to study the reason for the deviation, however, value of the amplitude turns out to be robust with respect to these errors. The only significant change in the amplitude is observed when we replace the minimum-variance CMB lensing map, used in the baseline analysis, by the lensing map derived from the CMB temperature map with deprojected thermal Sunyaev-Zeldovich signal.Comment: 15 pages, 13 figures, Published in MNRA

2D PbS Nanosheets Synthesis and Their Applications as Field Effect Transistors or Solar Cells

Two-dimensional, solution-processable semiconductor materials are interesting for low-cost electronic applications [1]. We demonstrate the synthesis of lead sulfide nanosheets and how their size, shape and height can be tuned by varying concentrations of pre-cursors, ligands and by varying the reaction temperature. Especially, the charge carrier confinement in the nanosheets' height adjustable from 2 to 20 nm has a decisive impact on their electronic properties. This is demonstrated by their use as conduction channel in a field effect transistor [2]. Recently we also showed that especially thin nanosheets show a high carrier multiplication (CM) efficiency [3] which could make them, through the confinement induced band gap and high photoconductivity, very attractive for application in photovoltaic devices. We are already able to manufacture photovoltaic devices out of single nanosheets which show promising results

2D PbS Nanosheets Synthesis and Their Applications as Field Effect Transistors or Solar Cells

Two-dimensional, solution-processable semiconductor materials are interesting for low-cost electronic applications [1]. We demonstrate the synthesis of lead sulfide nanosheets and how their size, shape and height can be tuned by varying concentrations of pre-cursors, ligands and by varying the reaction temperature. Especially, the charge carrier confinement in the nanosheets' height adjustable from 2 to 20 nm has a decisive impact on their electronic properties. This is demonstrated by their use as conduction channel in a field effect transistor [2]. Recently we also showed that especially thin nanosheets show a high carrier multiplication (CM) efficiency [3] which could make them, through the confinement induced band gap and high photoconductivity, very attractive for application in photovoltaic devices. We are already able to manufacture photovoltaic devices out of single nanosheets which show promising results

Cardioprotective effects of coffee

Coffee is one of the most consumed beverages among adults. Popular for its stimulant properties, it is also appreciated for its taste and is an essential part of many people's daily lives. Coffee, in addition to caffeine, contains macroelements such as sodium, potassium and magnesium, which ensure the proper functioning of the body, as well as polyphenols which are characterised by their anti-inflammatory properties. [1,2] Atrial fibrillation is the most common arrhythmia and caffeine is often considered a potential risk factor. [3] The purpose of this article is to evaluate current scientific reports on the relationship between coffee consumption and atrial fibrillation