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Halo models and halo occupation distributions (HODs) are important tools to model the galaxy and matter distribution. We present and assess a new method for constraining the parameters of HODs using the gravitational lensing shear around galaxy pairs, galaxy-galaxy-galaxy-lensing (G3L). In contrast to galaxy-galaxy-lensing, G3L is sensitive to correlations between the per-halo numbers of galaxies from different populations. We use G3L to probe these correlations and test the default hypothesis that they are negligible. We derive a halo model for G3L and validate it with realistic mock data from the Millennium Simulation and a semi-analytic galaxy model. Then, we analyse public data from the Kilo-Degree Survey (KiDS), the VISTA Infrared Kilo-Degree Galaxy Survey (VIKING) and data from the Galaxy And Mass Assembly Survey (GAMA) to infer the HODs of galaxies at $z<0.5$ in five different stellar mass bins between $10^{8.5}h^{-2} M_\odot$ and $10^{11.5}h^{-2} M_\odot$ and two colours (red and blue), as well as correlations between satellite numbers. The analysis recovers the true HODs in the simulated data within the $68\%$ credibility range. The inferred HODs vary significantly with colour and stellar mass. There is also strong evidence ($>3\sigma$) for correlations, increasing with halo mass, between the numbers of red and blue satellites and galaxies with stellar masses below $10^{10} \Msun. Possible causes of these correlations are the selection of similar galaxies in different samples, the survey flux limit, or physical mechanisms like a fixed ratio between the satellite numbers of distinct populations. The decorrelation for halos with smaller masses is probably an effect of shot noise by low-occupancy halos. The inferred HODs can be used to complement galaxy-galaxy-lensing or galaxy clustering HOD studies or as input to cosmological analyses and improved mock galaxy catalogues., Comment: 20 pages + Appendix, 14 Figures. Submitted to Astronomy & Astrophysics. Abstract is abridged

Background: In DR Congo, South Kivu is among cities most affected by Covid 19 with its dense population and common mass movement. This study aimed at investigating the population beha­vior and practices during the spread period of Corona in South Kivu, East of Democratic Republic of Congo.Subjects dan Method: A cross-sectional analytical study was undertaken in South Kivu province and included 800 hundred individuals. The survey questionnaire was designed and comprised information on independent variables including socio-demographic and socioeconomic para­meters, travel history of individuals, and person's history of COVID-19 comorbidity factors. These data were used to explain the depen­dent variable which was the population behavior and practices which was linked to the COVID-19 positivity or negativity. A rapid test of the COVID-19 antigen for people suspected of having cough and fever followed by RT-PCR tests was conducted. Statistical analyses were performed under R, version 3.5.1.Results: Results indicate three categories of people depending on their behavior and practices during the COVID-19. These include the negative group, those who contracted the disease and knew their serological status, and those who did not know their serological status. The behavior of these categories varied with age, education level, income, and their geographical location. Variable behaviors have been adopted, including lack of action, prayer, self-medication, lifestyle change, and change in feeding. Efforts to control the spread of the disease entailed two most commonly used barriers: wearing a mask (95%) and frequent hand washing (94%). In the COVID-19 infected category, type 1 individuals developed the most characteristic symptoms of COVID-19, mainly cough, asthenia, fever, and headache. Types 2 and 3 individuals were less likely to engage in any of the behaviors associated with COVID-19 because they have fewer comorbidities and have developed fewer of the symptoms characteristi

Busulfan and cyclophosphamide (BuCy) is a frequently used myeloablative conditioning regimen for allogeneic hematopoietic cell transplantation (allo-HCT). Theoretical considerations and pharmacological data indicate that application of busulfan prior to subsequent cyclophosphamide (BuCy) may trigger liver toxicity. Reversing the order of application to cyclophosphamide-busulfan (CyBu) might be preferable, a hypothesis supported by animal data and retrospective studies. We performed a prospective randomized trial to determine impact of order of application of Bu and Cy before allo-HCT in 70 patients with hematological malignancy, 33 patients received BuCy and 37 CyBu for conditioning. In the short term, there were minimal differences in liver toxicity favoring CyBu over BuCy, significant only for alanine amino transferase at day 30 (p = 0.03). With longer follow-up at 4 years, non-relapse mortality (6% versus 27%, p = 0.05) was lower and survival (63% versus 43%, p = 0.06) was higher with CyBu compared to BuCy. Other outcomes, such as engraftment (p = 0.21), acute and chronic graft-versus-host disease (p = 0.40; 0.36), and relapse (p = 0.79), were similar in both groups. We prospectively show evidence that the order of application of Cy and Bu in myeloablative conditioning in allo-HCT patients has impact on outcome.

Several semi-analytic models (SAMs) try to explain how galaxies form, evolve and interact inside the dark matter large-scale structure. These SAMs can be tested by comparing their predictions for galaxy-galaxy-galaxy-lensing (G3L), which is weak gravitational lensing around galaxy pairs, with observations. We evaluate the SAMs by Henriques et al. (2015; H15) and by Lagos et al. (2012; L12), implemented in the Millennium Run, by comparing their predictions for G3L to observations at smaller scales than previous studies and also for pairs of lens galaxies from different populations. We compare the G3L signal predicted by the SAMs to measurements in the overlap of the Galaxy And Mass Assembly survey (GAMA), the Kilo-Degree Survey (KiDS), and the VISTA Kilo-degree Infrared Galaxy survey (VIKING), splitting lens galaxies into two colour and five stellar-mass samples. Using an improved G3L estimator, we measure the three-point correlation of the matter distribution for mixed lens pairs with galaxies from different samples, and unmixed lens pairs with galaxies from the same sample. Predictions by the H15 SAM agree with the observations for all colour-selected and all but one stellar-mass-selected sample with 95% confidence. Deviations occur for lenses with stellar masses below $9.5h^{-2}\mathrm{M}_\odot$ at scales below $0.2h^{-1}\mathrm{Mpc}$. Predictions by the L12 SAM for stellar-mass selected samples and red galaxies are significantly higher than observed, while the predicted signal for blue galaxy pairs is too low. The L12 SAM predicts more pairs of small stellar-mass and red galaxies than the H15 SAM and the observations, as well as fewer pairs of blue galaxies. Likely explanations are different treatments of environmental effects by the SAMs and different models of the initial mass function. We conclude that G3L provides a stringent test for models of galaxy formation and evolution., Comment: 14 pages, 8 figures, replaced with version accepted to Astronomy & Astrophysics after considering referees comments

We explore an alternative method to the usual shear correlation function approach for the estimation of aperture mass statistics in weak lensing survey data. Our approach builds on the direct estimator method of Schneider (1998). In this paper, to test and validate the methodology, we focus on the aperture mass dispersion. After computing the signal and noise for a weighted set of measured ellipticites we show how the direct estimator can be made into a linear order algorithm that enables a fast and efficient computation. We then investigate the applicability of the direct estimator approach in the presence of a real survey mask with holes and chip gaps. For this we use a large ensemble of full ray-tracing mock simulations. By using various weighting schemes for combining information from different apertures we find that inverse variance weighting the individual aperture estimates with an aperture completeness greater than 70 per cent coverage yields an answer that is in close agreement with the standard correlation function approach. We then apply this approach to the CFHTLenS as pilot scheme and find that our method recovers to high accuracy the Kilbinger (2013) result for the variance of both the E and B mode signal, after we correct the catalogue for the shear bias in the lensfit algorithm for pairs closer than 9". We then explore the cosmological information content of the direct estimator using the Fisher information approach. We show that there is a only modest loss in cosmological information from the rejection of apertures that are of low completeness. This method unlocks the door to fast and efficient methods for recovering higher order aperture mass statistics in linear order operations., Comment: 26 pages, 15 figures. Submitted to MNRAS, comments welcome. v2: updated MNRAS template

We present a mitigation strategy to reduce the impact of non-linear galaxy bias on the joint `$3 \times 2 $pt' cosmological analysis of weak lensing and galaxy surveys. The $\Psi$-statistics that we adopt are based on Complete Orthogonal Sets of E/B Integrals (COSEBIs). As such they are designed to minimise the contributions to the observable from the smallest physical scales where models are highly uncertain. We demonstrate that $\Psi$-statistics carry the same constraining power as the standard two-point galaxy clustering and galaxy-galaxy lensing statistics, but are significantly less sensitive to scale-dependent galaxy bias. Using two galaxy bias models, motivated by halo-model fits to data and simulations, we quantify the error in a standard $3 \times 2$pt analysis where constant galaxy bias is assumed. Even when adopting conservative angular scale cuts, that degrade the overall cosmological parameter constraints, we find of order $1 \sigma$ biases for Stage III surveys on the cosmological parameter $S_8 = \sigma_8(\Omega_{\rm m}/0.3)^{\alpha}$. This arises from a leakage of the smallest physical scales to all angular scales in the standard two-point correlation functions. In contrast, when analysing $\Psi$-statistics under the same approximation of constant galaxy bias, we show that the bias on the recovered value for $S_8$ can be decreased by a factor of $\sim 2$, with less conservative scale cuts. Given the challenges in determining accurate galaxy bias models in the highly non-linear regime, we argue that $3 \times 2$pt analyses should move towards new statistics that are less sensitive to the smallest physical scales., Comment: 14 pages, 13 figures, accepted to be published in MNRAS

Electrical breakdown in the oxidized barrier of hydrogen-terminated and thus surface-conductive diamond devices is a limiting factor in the fabrication of nanoscale structures. Possible applications as a free electron source as well as the electron transport across the potential barrier are investigated in this work. We report on a reduced effective barrier height due to an inhomogeneous potential landscape and a new field-dependent optical absorption feature at this interface. A new defect level is proposed that is formed at the hydrogen-/oxygen-terminated interface., Elektrische Leckströme über die Potentialbarriere von Wasserstoff-terminiertem und somit oberflächen-leitfähigem Diamant limitieren derzeit die Miniaturisierung entsprechender Diamantbauteile. In dieser Arbeit wird ein Einsatz dieser Oberfläche als freie Elektronenquelle untersucht und zusätzlich der elektrische Transport über die Sauerstoff-terminierte Potentialbarriere. Eine inhomogene Potentiallandschaft ist sowohl verantwortlich für eine reduzierte Barrierenhöhe als auch für die Feldabhängigkeit einer neuen optischen Absorptionsbande. Dies wird ermöglicht durch einen neuen Defekt am Übergang von Wasserstoff- zu Sauerstoff-Terminierung.

Galaxy models predict a tight relation between the clustering of galaxies and dark matter on cosmological scales, but predictions differ notably in the details. We used this opportunity and tested two semi-analytic models by the Munich and Durham groups with data from the Canada-France-Hawaii Telescope Lensing Survey (CFHTLenS). For the test we measured the scale-dependent galaxy bias factor $b(k)$ and correlation factor $r(k)$ from linear to non-linear scales of $k\approx10\,h\,\rm Mpc^{-1}$ at two redshifts $\bar{z}=0.35,0.51$ for galaxies with stellar mass between $5\times10^9$ and $3\times10^{11}\,h_{\rm 70}^{-2}\,{\rm M}_\odot$. Our improved gravitational lensing technique accounts for the intrinsic alignment of sources and the magnification of lens galaxies for better constraints for the galaxy-matter correlation $r(k)$. Galaxy bias in CFHTLenS increases with $k$ and stellar mass, it is colour-dependent, revealing the individual footprints of galaxy types. Despite a reasonable model agreement for the relative change with both scale and galaxy properties, there is a clear conflict for $b(k)$ with no model preference: the model galaxies are too weakly clustered. This may flag a model problem at $z\gtrsim0.3$ for all stellar masses. As in the models, however, there is a high correlation $r(k)$ between matter and galaxy density on all scales, and galaxy bias is typically consistent with a deterministic bias on linear scales. Only our blue and low-mass galaxies of about $7\times10^9\,h_{\rm 70}^{-2}\,{\rm M}_\odot$ at $\bar{z}=0.51$ show, contrary to the models, a weak tendency towards a stochastic bias on linear scales where $r_{\rm ls}=0.75\pm0.14\,{\rm(stat.)}\pm0.06\,{\rm(sys.)}$. This result is of interest for cosmological probes, such as $E_{\rm G}$, that rely on a deterministic galaxy bias., Comment: 17+13(Appendix) pages, 13+6 figures; Figs. A.1-A.4 are key figures; accepted by A&A, in press; Monte-Carlo realisations of $b(k)$ and $r(k)$ will be provided as online material on http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A

Electrical breakdown at hydrogen/oxygen interfaces is limiting the use of nanoscaled diamond devices for the control of optically active defect centers. In this work electron transport across an oxygen-terminated potential barrier in a hydrogen-terminated surface conductive diamond is investigated. We analyze temperature-dependent current-voltage characteristics for different barrier widths and report on a reduced effective barrier height compared to theoretical expectations. This is ascribed to an inhomogeneous potential landscape, as observed by Kelvin probe and conductive force microscopy. Furthermore, we use photocurrent spectroscopy to discuss possible transport processes and identify a field dependent absorption feature. A defect state involved in transport across the barrier is proposed at the hydrogen-oxygen barrier approximately 1eV above the valence band maximum. The new understanding enabled by our work may help to overcome the current limitations of diamond surface electronics.

Magnification changes the observed number counts of galaxies on the sky. This biases the observed tangential shear profiles around galaxies, the so-called galaxy-galaxy lensing (GGL) signal, and the related excess mass profile. Correspondingly, inference of physical quantities, such as the mean mass profile of halos around galaxies, are affected by magnification effects. We use simulated shear and galaxy data of the Millennium Simulation to quantify the effect on shear and mass estimates from magnified lens and source number counts. The former are due to the large-scale matter distribution in the foreground of the lenses, the latter are caused by magnification of the source population by the matter associated with the lenses. The GGL signal is calculated from the simulations by an efficient fast-Fourier transform that can also be applied to real data. The numerical treatment is complemented by a leading-order analytical description of the magnification effects, which is shown to fit the numerical shear data well. We find the magnification effect is strongest for steep galaxy luminosity functions and high redshifts. For a lens redshift of $z_\mathrm{d}=0.83$, a limiting magnitude of $22\,\mathrm{mag}$ in the $r$-band and a source redshift of $z_\mathrm{s}=0.99$, we find that a magnification correction changes the shear profile up to $45\%$ and the mass is biased by up to $55 \%$. For medium-redshift galaxies the relative change in shear and mass is typically a few percent. As expected, the sign of the bias depends on the local slope of the lens luminosity function $\alpha_\mathrm{d}$, where the mass is biased low for $\alpha_\mathrm{d}<1$ and biased high for $\alpha_\mathrm{d}>1$. Whereas the magnification effect of sources is rarely than more $1\%$, the statistical power of future weak lensing surveys warrants correction for this effect., Comment: this version fixes a typo in the prefactor of equation (14)

Galaxy-galaxy-galaxy lensing (G3L) is a powerful tool for constraining the three-point correlation between the galaxy and matter distribution and thereby models of galaxy evolution. We propose three improvements to current measurements of G3L: (i) a weighting of lens galaxies according to their redshift difference, (ii) adaptive binning of the three-point correlation function, and (iii) accounting for the effect of lens magnification by the cosmic large-scale structure. Improvement (i) is designed to improve the precision of the G3L measurement, whereas improvements (ii) and (iii) remove biases of the estimator. We further show how the G3L signal can be converted from angular into physical scales. The improvements were tested on simple mock data and simulated data based on the Millennium Run with an implemented semi-analytic galaxy model. Our improvements increase the signal-to-noise ratio by 35 % on average at angular scales between 0.1 arcmin and 10 arcmin and physical scales between $0.02$ and $2 \, h^{-1}\, \textrm{Mpc}$. They also remove the bias of the G3L estimator at angular scales below 1 arcmin, which was originally up to 40 %. The signal due to lens magnification is approximately 10 % of the total signal., Comment: 15 pages, 10 figures, replaced by revised version accepted for A&A after addressing referees comments

Carbon capture and storage (CCS) is required in order to reduce the impact of fossil fuel burning on global warming and the resulting climate change. The use of CCS technology offers much promise in regard to the capture of major levels of waste carbon dioxide produced from the burning of fossil fuels for electricity generation and from industrial processes. Crucial to the development of CCS technology is the need for improved decision-making tools to underpin sustainable investment and associated policy initiatives for CCS technology and infrastructure. Consequently, this paper provides the results from the techno-economic analysis of CCS. This includes regression modelling of the levelized cost of electricity for power generation via combined cycle gas turbine both with and without CCS. In order to inform future research in the area, a supporting CCS research agenda has been formulated.

Microthermometric measurements of a synthetic high-density (984 kg/m-3) water inclusion in quartz revealed that only part of the super-cooled liquid water (L) transforms to solid ice Ih upon ice nucleation (L → ice Ih + L). While ice nucleation occurs in the ice Ih stability field at –41 °C and 28 MPa the pressure increases instantaneously to 315 MPa into the ice II stability field. At this point, both phases, liquid water and ice Ih are metastable. The coexistence of these two phases was confirmed by Raman spectroscopy and could be traced down to –80 °C. The pressure along this low-temperature metastable extension of the ice Ih melting curve was determined by means of the frequency shift of the ice Ih peak position using both the O–H stretching band around 3100 cm-1 and the lattice translational band around 220 cm-1. At –80 °C and 466 MPa the super-cooled ice Ih melting curve encounters the homogeneous nucleation limit (TH) and the remaining liquid water transformed either to metastable ice IV (ice Ih + L→ ice Ih + ice IV) oroccasionally to metastable ice III (ice Ih + L→ ice Ih + ice III). The nucleation of ice IV resulted in a pressure drop of about 180 MPa. Upon subsequent heating the pressure develops along a slightly negatively sloped ice Ih-ice IV equilibrium line terminating in a triple point at –32.7 °C and 273 MPa, where ice IV melts to liquid water (ice Ih + ice IV → ice Ih + L). Hitherto existing experimental data of the ice IV melting curve (ice IV → L) were found to be in line with the observed ice Ih-ice IV-liquid triple point. If, on the other hand, ice III nucleated at –80 °C (instead of ice IV) the associated pressure drop was about 260 MPa. The ice Ih-ice III-liquid triple point was determined at –22.0 °C and 207 MPa (ice Ih + ice III → ice Ih + L), which is in agreement wit

Importance: Short-term infusions of single vasodilators, usually given in a fixed dose, have not improved outcomes in patients with acute heart failure (AHF). Objective: To evaluate the effect of a strategy that emphasized early intensive and sustained vasodilation using individualized up-titrated doses of established vasodilators in patients with AHF. Design, Setting, and Participants: Randomized, open-label blinded-end-point trial enrolling 788 patients hospitalized for AHF with dyspnea, increased plasma concentrations of natriuretic peptides, systolic blood pressure of at least 100 mm Hg, and plan for treatment in a general ward in 10 tertiary and secondary hospitals in Switzerland, Bulgaria, Germany, Brazil, and Spain. Enrollment began in December 2007 and follow-up was completed in February 2019. Interventions: Patients were randomized 1:1 to a strategy of early intensive and sustained vasodilation throughout the hospitalization (n = 386) or usual care (n = 402). Early intensive and sustained vasodilation was a comprehensive pragmatic approach of maximal and sustained vasodilation combining individualized doses of sublingual and transdermal nitrates, low-dose oral hydralazine for 48 hours, and rapid up-titration of angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, or sacubitril-valsartan. Main Outcomes and Measures: The primary end point was a composite of all-cause mortality or rehospitalization for AHF at 180 days. Results: Among 788 patients randomized, 781 (99.1%; median age, 78 years; 36.9% women) completed the trial and were eligible for primary end point analysis. Follow-up at 180 days was completed for 779 patients (99.7%). The primary end point, a composite of all-cause mortality or rehospitalization for AHF at 180 days, occurred in 117 patients (30.6%) in the intervention group (including 55 deaths [14.4%]) and in 111 patients (27.8%) in the usual care group (including 61 deaths [15.3%]) (absolute difference for the primary end

Galaxies are biased tracers of the matter density on cosmological scales. For future tests of galaxy models, we refine and assess a method to measure galaxy biasing as function of physical scale $k$ with weak gravitational lensing. This method enables us to reconstruct the galaxy bias factor $b(k)$ as well as the galaxy-matter correlation $r(k)$ on spatial scales between $0.01\,h\,{\rm Mpc^{-1}}\lesssim k\lesssim10\,h\,{\rm Mpc^{-1}}$ for redshift-binned lens galaxies below redshift $z\lesssim0.6$. In the refinement, we account for an intrinsic alignment of source ellipticities, and we correct for the magnification bias of the lens galaxies, relevant for the galaxy-galaxy lensing signal, to improve the accuracy of the reconstructed $r(k)$. For simulated data, the reconstructions achieve an accuracy of $3-7\%$ (68\% confidence level) over the above $k$-range for a survey area and a typical depth of contemporary ground-based surveys. Realistically the accuracy is, however, probably reduced to about $10-15\%$, mainly by systematic uncertainties in the assumed intrinsic source alignment, the fiducial cosmology, and the redshift distributions of lens and source galaxies (in that order). Furthermore, our reconstruction technique employs physical templates for $b(k)$ and $r(k)$ that elucidate the impact of central galaxies and the halo-occupation statistics of satellite galaxies on the scale-dependence of galaxy bias, which we discuss in the paper. In a first demonstration, we apply this method to previous measurements in the Garching-Bonn-Deep Survey and give a physical interpretation of the lens population., Comment: 31 pages, 16 figures; corrected typos in Eqs. (31), (34), and (36)

We compute the spherical-sky weak-lensing power spectrum of the shear and convergence. We discuss various approximations, such as flat-sky, and first- and second- order Limber equations for the projection. We find that the impact of adopting these approximations is negligible when constraining cosmological parameters from current weak lensing surveys. This is demonstrated using data from the Canada-France-Hawaii Telescope Lensing Survey (CFHTLenS). We find that the reported tension with Planck Cosmic Microwave Background (CMB) temperature anisotropy results cannot be alleviated. For future large-scale surveys with unprecedented precision, we show that the spherical second-order Limber approximation will provide sufficient accuracy. In this case, the cosmic-shear power spectrum is shown to be in agreement with the full projection at the sub-percent level for l > 3, with the corresponding errors an order of magnitude below cosmic variance for all l. When computing the two-point shear correlation function, we show that the flat-sky fast Hankel transformation results in errors below two percent compared to the full spherical transformation. In the spirit of reproducible research, our numerical implementation of all approximations and the full projection are publicly available within the package nicaea at http://www.cosmostat.org/software/nicaea., Comment: 17 pages, 5 figures, 2 tables. Matches published version (MNRAS, 2017, 472, 2126)

We present weak lensing constraints on the ellipticity of galaxy-scale matter haloes and the galaxy-halo misalignment. Using data from the Canada-France-Hawaii Telescope Lensing Survey (CFHTLenS), we measure the weighted-average ratio of the aligned projected ellipticity components of galaxy matter haloes and their embedded galaxies, fh, split by galaxy type. We then compare our observations to measurements taken from the Millennium Simulation, assuming different models of galaxy-halo misalignment. Using the Millennium Simulation, we verify that the statistical estimator used removes contamination from cosmic shear. We also detect an additional signal in the simulation, which we interpret as the impact of intrinsic shape-shear alignments between the lenses and their large-scale structure environment. These alignments are likely to have caused some of the previous observational constraints on fh to be biased high. From CFHTLenS, we find fh=−0.04±0.25 for early-type galaxies, which is consistent with current models for the galaxy-halo misalignment predicting fh ≃ 0.20. For late-type galaxies we measure $f_\mathrm{h}=0.69_{-0.36}^{+0.37}$ from CFHTLenS. This can be compared to the simulated results which yield fh ≃ 0.02 for misaligned late-type models

In weak gravitational lensing, weighted quadrupole moments of the brightness profile in galaxy images are a common way to estimate gravitational shear. We employ general adaptive moments (GLAM) to study causes of shear bias on a fundamental level and for a practical definition of an image ellipticity. The GLAM ellipticity has useful properties for any chosen weight profile: the weighted ellipticity is identical to that of isophotes of elliptical images, and in absence of noise and pixellation it is always an unbiased estimator of reduced shear. We show that moment-based techniques, adaptive or unweighted, are similar to a model-based approach in the sense that they can be seen as imperfect fit of an elliptical profile to the image. Due to residuals in the fit, moment-based estimates of ellipticities are prone to underfitting bias when inferred from observed images. The estimation is fundamentally limited mainly by pixellation which destroys information on the original, pre-seeing image. We give an optimized estimator for the pre-seeing GLAM ellipticity and quantify its bias for noise-free images. To deal with pixel noise, we consider a Bayesian approach where the posterior of the GLAM ellipticity can be inconsistent with the true ellipticity if we do not properly account for our ignorance about fit residuals. This underfitting bias is S/N-independent but changes with the pre-seeing brightness profile and the correlation or heterogeneity of pixel noise over the post-seeing image. Furthermore, when inferring a constant ellipticity or, more relevantly, constant shear from a source sample with a distribution of intrinsic properties (sizes, centroid positions, intrinsic shapes), an additional, now noise-dependent bias arises towards low S/N if incorrect priors for the intrinsic properties are used. We discuss the origin of this prior bias., Comment: 18 pages; 5 figures; accepted by A&A after major revision, especially of Sect. 3.3 that corrects the previous discussion on the bias by marginalization

Testing predictions of semi-analytic models of galaxy evolution against observations help to understand the complex processes that shape galaxies. We compare predictions from the Garching and Durham models implemented on the Millennium Run with observations of galaxy-galaxy lensing (GGL) and galaxy-galaxy-galaxy lensing (G3L) for various galaxy samples with stellar masses in the range 0.5 < (M_* / 10^10 M_Sun) < 32 and photometric redshift range 0.2 < z < 0.6 in the Canada-France-Hawaii Telescope Lensing Survey (CFHTLenS). We find that the predicted GGL and G3L signals are in qualitative agreement with CFHTLenS data. Quantitatively, the models succeed in reproducing the observed signals in the highest stellar mass bin (16 < ( M_* / 10^10 M_Sun) < 32) but show different degrees of tension for the other stellar mass samples. The Durham models are strongly excluded at the 95% confidence level by the observations as they largely over-predict the amplitudes of the GGL and G3L signals, probably because they predict too many satellite galaxies in massive halos., Comment: 9 pages, 8 figures, submitted to A&A. Comments welcome

One means by which Intolerance of Uncertainty (IU) purports to contribute to anxiety is by increasing Threat Perception (TP). This process was examined by comparing two different definitions of uncertainty: ambiguity versus unpredictability. N = 104 participants were measured for IU and then made worry and TP estimates for four different scenario types: Ambiguous Scenarios (where an outcome could be interpreted as threatening), Unpredictable Positive Scenarios (where a surprising and positive outcome was anticipated), as well as Positive and Negative Scenarios (with certain outcome). Both Ambiguous and Unpredictable Positive Scenarios more strongly predicted the relationship between IU and worry scores than (certain) Positive or Negative Scenarios. The relationship between IU and 'ambiguous worry' was largely explained by TP estimates, whereas the relationship between IU and 'Unpredictable Positive Worry' was largely independent of TP. Results suggest ambiguity and unpredictability are differentially explained by TP such that they produce different types of response. The authors argue ambiguity and unpredictability are explanatory components within IU.

The Kilo-Degree Survey (KiDS) is a multi-band imaging survey designed for cosmological studies from weak lensing and photometric redshifts. It uses the ESO VLT Survey Telescope with its wide-field camera OmegaCAM. KiDS images are taken in four filters similar to the SDSS ugri bands. The best-seeing time is reserved for deep r-band observations that reach a median 5-sigma limiting AB magnitude of 24.9 with a median seeing that is better than 0.7arcsec. Initial KiDS observations have concentrated on the GAMA regions near the celestial equator, where extensive, highly complete redshift catalogues are available. A total of 109 survey tiles, one square degree each, form the basis of the first set of lensing analyses, which focus on measurements of halo properties of GAMA galaxies. 9 galaxies per square arcminute enter the lensing analysis, for an effective inverse shear variance of 69 per square arcminute. Accounting for the shape measurement weight, the median redshift of the sources is 0.53. KiDS data processing follows two parallel tracks, one optimized for galaxy shape measurement (for weak lensing), and one for accurate matched-aperture photometry in four bands (for photometric redshifts). This technical paper describes how the lensing and photometric redshift catalogues have been produced (including an extensive description of the Gaussian Aperture and Photometry pipeline), summarizes the data quality, and presents extensive tests for systematic errors that might affect the lensing analyses. We also provide first demonstrations of the suitability of the data for cosmological measurements, and explain how the shear catalogues were blinded to prevent confirmation bias in the scientific analyses. The KiDS shear and photometric redshift catalogues, presented in this paper, are released to the community through http://kids.strw.leidenuniv.nl ., Comment: 37 pages. MNRAS, accepted. Minor updates with respect to first submission, including total number of survey tiles included. Catalogues are available at http://kids.strw.leidenuniv.nl

We present weak lensing constraints on the ellipticity of galaxy-scale matter haloes and the galaxy-halo misalignment. Using data from the Canada-France-Hawaii Telescope Lensing Survey (CFHTLenS), we measure the weighted-average ratio of the aligned projected ellipticity components of galaxy matter haloes and their embedded galaxies, $f_\mathrm{h}$, split by galaxy type. We then compare our observations to measurements taken from the Millennium Simulation, assuming different models of galaxy-halo misalignment. Using the Millennium Simulation we verify that the statistical estimator used removes contamination from cosmic shear. We also detect an additional signal in the simulation, which we interpret as the impact of intrinsic shape-shear alignments between the lenses and their large-scale structure environment. These alignments are likely to have caused some of the previous observational constraints on $f_\mathrm{h}$ to be biased high. From CFHTLenS we find $f_\mathrm{h}=-0.04 \pm 0.25$ for early-type galaxies, which is consistent with current models for the galaxy-halo misalignment predicting $f_\mathrm{h}\simeq 0.20$. For late-type galaxies we measure $f_\mathrm{h}=0.69_{-0.36}^{+0.37}$ from CFHTLenS. This can be compared to the simulated results which yield $f_\mathrm{h}\simeq 0.02$ for misaligned late-type models., Comment: 21 pages, 3 tables, 9 figures. This replacement matches the version accepted for publication in MNRAS

This thesis applies the historiography of the early modern public sphere to analyze the political literature which militated for curricular and structural reform of England’s universities during the Civil War and Interregnum (1642-1660). The writers considered, who represent the breadth of the political and confessional spectra, advanced a multitude of reform schemes that variably proposed to topple Aristotle from the curricula, replace Oxford and Cambridge with local trade schools and abolish the Bachelor of Divinity degree. Alumni of these institutions led the effort to restructure the institutions but managed to garner wide popular readership amongst individuals who had no experience of university education. This thesis argues that the learned authors manipulated the increasingly popular recognition of a public sphere in order to underline the political threats which scholarly publications, generic conventions and overall “pedantry” in the universities posed to the nascent commonwealth. It further examines how divergent conceptions of the public sphere divided the reformist literature and ultimately produced a body of conflicting proposals for positive reform. This interpretation of the university reform debate thereby challenges the accepted historiography that characterizes the Interregnum as a stable and unrevolutionary episode in the history of the universities.

Higher-order, non-Gaussian aspects of the large-scale structure carry valuable information on structure formation and cosmology, which is complementary to second-order statistics. In this work we measure second- and third-order weak-lensing aperture-mass moments from CFHTLenS and combine those with CMB anisotropy probes. The third moment is measured with a significance of $2\sigma$. The combined constraint on $\Sigma_8 = \sigma_8 (\Omega_{\rm m}/0.27)^\alpha$ is improved by 10%, in comparison to the second-order only, and the allowed ranges for $\Omega_{\rm m}$ and $\sigma_8$ are substantially reduced. Including general triangles of the lensing bispectrum yields tighter constraints compared to probing mainly equilateral triangles. Second- and third-order CFHTLenS lensing measurements improve Planck CMB constraints on $\Omega_{\rm m}$ and $\sigma_8$ by 26% for flat $\Lambda$CDM. For a model with free curvature, the joint CFHTLenS-Planck result is $\Omega_{\rm m} = 0.28 \pm 0.02$ (68% confidence), which is an improvement of 43% compared to Planck alone. We test how our results are potentially subject to three astrophysical sources of contamination: source-lens clustering, the intrinsic alignment of galaxy shapes, and baryonic effects. We explore future limitations of the cosmological use of third-order weak lensing, such as the nonlinear model and the Gaussianity of the likelihood function., Comment: Accepted by MNRAS. 21 pages, 14 figues, 8 tables. The data is available at http://www.cfhtlens.org . The software used for the cosmological analysis can be downloaded from http://cosmopmc.info

The Balder, Grane and Ringhorne oil fields locate on the north-western flank of the Utsira High in the Norwegian sector of the North Sea. Reservoir sandstones deposited by gravity flows during the Palaeocene and Eocene Epochs originate from the East Shetland platform, to the West. The post-deposition effects of remobilization and injection are known to distort deposited sandstones creating irregular reservoir characteristics. It is also known that post-depositional processes are non-uniform, affecting sedimentary bodies variably. Low magnitude remobilization will cause minor geometrical distortion, whereas high magnitude deformation connects noncontemporaneous sands, destroying depositional geometries and potentially complicating hydrocarbon extraction. Cored section, wireline logs and 3D seismic data allow description of the reservoir interval. Wireline logs do not facilitate identification of post-depositional processes, as remobilized and injected sandstone posses a non-unique signature. Cored section, however, allows direct identification of remobilized and injected sandstones. Seismic data, when calibrated by cored section can identify remobilized and injected sandstones. However, injected sandstones observed in cored section in Balder and Ringhorne Fields is seismically unresolvable. Eighteen steep sided mounds are identified in the study area. Seismic geometries tentatively suggest Balder Field as having experience higher magnitude soft sediment deformation than Grane Field, which is of a higher magnitude than Ringhorne Field. Crosscutting seismic reflections emanate from crests and flanks of mounds in Balder Field and Grane Fields. Injected sandstones are identified in cored section in each of the field areas.

Identifying the emerging requirements for technology management will help organisations to prepare for the future and remain competitive. Indeed technology management as a discipline needs to develop and respond to societal and industrial needs as well as the corresponding technology challenges. Therefore, following a review of technology forecasting methodologies, a sector-based scenario planning approach has been used to derive the emerging requirements for technology management. This structured framework provided an analytical lens to focus on the requirements for managing technology in the healthcare, energy and higher education sectors over the next 5-10 years. These requirements include the need for new business models to support the adoption of technologies; integration of new technologies with existing delivery channels; management of technology options including R&D project management; technology standards, validation and interoperability; and decision-making tools to support technology investment.

Identifying the emerging requirements for technology management will help organisations to prepare for the future and remain competitive. Indeed technology management as a discipline needs to develop and respond to societal and industrial needs as well as the corresponding technology challenges. Therefore, following a review of technology forecasting methodologies, a sector-based scenario planning approach has been used to derive the emerging requirements for technology management. This structured framework provided an analytical lens to focus on the requirements for managing technology in the healthcare, energy and higher education sectors over the next 5-10 years. These requirements include the need for new business models to support the adoption of technologies; integration of new technologies with existing delivery channels; management of technology options including R&D project management; technology standards, validation and interoperability; and decision-making tools to support technology investment.

We present the Canada-France-Hawaii Telescope Lensing Survey (CFHTLenS) that accurately determines a weak gravitational lensing signal from the full 154 square degrees of deep multi-colour data obtained by the CFHT Legacy Survey. Weak gravitational lensing by large-scale structure is widely recognised as one of the most powerful but technically challenging probes of cosmology. We outline the CFHTLenS analysis pipeline, describing how and why every step of the chain from the raw pixel data to the lensing shear and photometric redshift measurement has been revised and improved compared to previous analyses of a subset of the same data. We present a novel method to identify data which contributes a non-negligible contamination to our sample and quantify the required level of calibration for the survey. Through a series of cosmology-insensitive tests we demonstrate the robustness of the resulting cosmic shear signal, presenting a science-ready shear and photometric redshift catalogue for future exploitation., Comment: MNRAS in press (accepted 15th August 2012), 21 pages with 12 figures. See http://www.cfhtlens.org for information about the upcoming CFHTLenS full data release

The gravitational lensing effect provides various ways to study the mass environment of galaxies. We investigate how galaxy-galaxy(-galaxy) lensing can be used to test models of galaxy formation and evolution. We consider two semi-analytic galaxy formation models based on the Millennium Run N-body simulation: the Durham model by Bower et al. (2006) and the Garching model by Guo et al. (2011). We generate mock lensing observations for the two models, and then employ Fast Fourier Transform methods to compute second- and third-order aperture statistics in the simulated fields for various galaxy samples. We find that both models predict qualitatively similar aperture signals, but there are large quantitative differences. The Durham model predicts larger amplitudes in general. In both models, red galaxies exhibit stronger aperture signals than blue galaxies. Using these aperture measurements and assuming a linear deterministic bias model, we measure relative bias ratios of red and blue galaxy samples. We find that a linear deterministic bias is insufficient to describe the relative clustering of model galaxies below ten arcmin angular scales. Dividing galaxies into luminosity bins, the aperture signals decrease with decreasing luminosity for brighter galaxies, but increase again for fainter galaxies. This increase is likely an artifact due to too many faint satellite galaxies in massive group and cluster halos predicted by the models. Our study shows that galaxy-galaxy(-galaxy) lensing is a sensitive probe of galaxy evolution., Comment: 11 pages, 8 figures, accepted in A&A

The weak gravitational lensing distortion of distant galaxy images (defined as sources) probes the projected large-scale matter distribution in the Universe. To improve quality in the 3D mass mapping using 3D-lensing, we combine the lensing information with the spatial clustering of a population of galaxies that trace the matter density with a known galaxy bias (defined as tracers). For our minimum variance estimator, merely all the second-order bias of the tracers has to be known, which can in principle be self-consistently constrained in the data by lensing techniques. This synergy introduces a new noise component because of the stochasticity in the matter-tracer density relation. We give a description of the stochasticity noise in the Gaussian regime, and we investigate the estimator characteristics analytically. We apply the estimator to a mock survey based on the Millennium Simulation. The estimator linearly mixes the individual lensing mass and tracer number density maps into a combined smoothed mass map. The weighting in the mix depends on the S/N of the individual maps and the correlation, $r$, between the matter and galaxy density. The weight of the tracers can be reduced by hand. For moderate mixing, the S/N in the mass map improves by a factor $\sim2-3$ for $r\gtrsim0.4$; the systematic offset between a true and apparent mass peak distance ($z$-shift bias) in a lensing-only map is eliminated, even for weak correlations of $r\sim0.4$. If the second-order bias of tracer galaxies can be determined, the synergy technique potentially provides an option to improve redshift accuracy and completeness of the lensing 3D mass map. However,the estimator's performance on sub-degree, non-Gaussian scales depends on all details in the galaxy bias mechanism and, hence, its accuracy on the choice of the tracer population.[abridged], Comment: 15 pages, 8 figures, language corrections, A&A in press

With the availability of galaxy distance indicators in weak lensing surveys, lensing tomography can be harnessed to constrain the three-dimensional (3D) matter power spectrum over a range of redshift and physical scale. By combining galaxy-galaxy lensing and galaxy clustering, this can be extended to probe the 3D galaxy-matter and galaxy-galaxy power spectrum or, alternatively, galaxy biasing parameters. To achieve this aim, this paper introduces and discusses minimum variance estimators and a more general Bayesian approach to statistically invert a set of noisy tomography 2-point correlation functions, measured within a confined opening angle. Both methods are constructed such that they probe deviations of the power spectrum from a fiducial power spectrum, thereby enabling both a direct comparison of theory and data, and in principle the identification of the physical scale and redshift of deviations. By devising a new Monte Carlo technique, we quantify the measurement noise in the correlators for a fiducial survey, and test the performance of the inversion techniques. We conclude that a shear tomography analysis of near future weak lensing surveys promises fruitful insights into the effect of baryons on the nonlinear matter power spectrum at z<~0.3 around k~2 h/Mpc, and into galaxy biasing (z<~0.5). However, a proper treatment of anticipated systematics -- not included in the mock analysis but discussed here -- is likely to reduce the signal-to-noise in the analysis so that a robust assessment of the 3D matter power spectrum probably asks for a survey area of at least 1000 sdeg. [Abridged], Comment: 17 pages, 11 figures, accepted for publication by A&A; latest update is subject to language corrections

Third-order galaxy-galaxy lensing (G3L) is a next generation galaxy-galaxy lensing technique that either measures the excess shear about lens pairs or the excess shear-shear correlations about lenses. It is clear that these statistics assess the three-point correlations between galaxy positions and projected matter density. For future applications of these novel statistics, we aim at a more intuitive understanding of G3L to isolate the main features that possibly can be measured. We construct a toy model ("isolated lens model"; ILM) for the distribution of galaxies and associated matter to determine the measured quantities of the two G3L correlation functions and traditional galaxy-galaxy lensing (GGL) in a simplified context. The ILM presumes single lens galaxies to be embedded inside arbitrary matter haloes that, however, are statistically independent ("isolated") from any other halo or lens position. In the ILM, the average mass-to-galaxy number ratio of clusters of any size cannot change. GGL and galaxy clustering alone cannot distinguish an ILM from any more complex scenario. The lens-lens-shear correlator in combination with second-order statistics enables us to detect deviations from a ILM, though. This can be quantified by a difference signal defined in the paper. We demonstrate with the ILM that this correlator picks up the excess matter distribution about galaxy pairs inside clusters. The lens-shear-shear correlator is sensitive to variations among matter haloes. In principle, it could be devised to constrain the ellipticities of haloes, without the need for luminous tracers, or maybe even random halo substructure. [Abridged], Comment: 14 pages, 3 figures, 1 table, accepted by A&A; some "lens-shear-shear" were falsely "lens-lens-shear"

Context. Gravitational lensing is one of the leading tools in understanding the dark side of the Universe. The need for accurate, efficient and effective methods which are able to extract this information along with other cosmological parameters from cosmic shear data is ever growing. COSEBIs, Complete Orthogonal Sets of E-/B-Integrals, is a recently developed statistical measure that encompasses the complete E-/B-mode separable information contained in the shear correlation functions measured on a finite angular range. Aims. The aim of the present work is to test the properties of this newly developed statistics for a higher-dimensional parameter space and to generalize and test it for shear tomography. Methods. We use Fisher analysis to study the effectiveness of COSEBIs. We show our results in terms of figure-of-merit quantities, based on Fisher matrices. Results. We find that a relatively small number of COSEBIs modes is always enough to saturate to the maximum information level. This number is always smaller for 'logarithmic COSEBIs' than for 'linear COSEBIs', and also depends on the number of redshift bins, the number and choice of cosmological parameters, as well as the survey characteristics. Conclusions. COSEBIs provide a very compact way of analyzing cosmic shear data, i.e., all the E-/B-mode separable second-order statistical information in the data is reduced to a small number of COSEBIs modes. Furthermore, with this method the arbitrariness in data binning is no longer an issue since the COSEBIs modes are discrete. Finally, the small number of modes also implies that covariances, and their inverse, are much more conveniently obtainable, e.g., from numerical simulations, than for the shear correlation functions themselves., Comment: 17 pages, 15 figures

To investigate and specify the statistical properties of cosmological fields with particular attention to possible non-Gaussian features, accurate formulae for the bispectrum and the bispectrum covariance are required. The bispectrum is the lowest-order statistic providing an estimate for non-Gaussianities of a distribution, and the bispectrum covariance depicts the errors of the bispectrum measurement and their correlation on different scales. Currently, there do exist fitting formulae for the bispectrum and an analytical expression for the bispectrum covariance, but the former is not very accurate and the latter contains several intricate terms and only one of them can be readily evaluated from the power spectrum of the studied field. Neglecting all higher-order terms results in the Gaussian approximation of the bispectrum covariance. We study the range of validity of this Gaussian approximation for two-dimensional non-Gaussian random fields. For this purpose, we simulate Gaussian and non-Gaussian random fields, the latter represented by log-normal fields and obtained directly from the former by a simple transformation. From the simulated fields, we calculate the power spectra, the bispectra, and the covariance from the sample variance of the bispectra, for different degrees of non-Gaussianity \alpha, which is equivalent to the skewness on a given angular scale \theta g. We find that the Gaussian approximation provides a good approximation for \alpha<0.6 and a reasonably accurate approximation for \alpha< 1, both on scales >8\theta g. Using results from cosmic shear simulations, we estimate that the cosmic shear convergence fields are described by \alpha<0.7 at \theta g~4". We therefore conclude that the Gaussian approximation for the bispectrum covariance is likely to be applicable in ongoing and future cosmic shear studies., Comment: 8 pages, 12 figures, submitted to Astronomy and Astrophysics

BACKGROUND: Implantable cardioverter-defibrillators (ICDs) prevent sudden death from cardiac causes in selected patients but require the use of transvenous lead systems. To eliminate the need for venous access, we designed and tested an entirely subcutaneous ICD system. METHODS: First, we conducted two shortterm clinical trials to identify a suitable device configuration and assess energy requirements. We evaluated four subcutaneous ICD configurations in 78 patients who were candidates for ICD implantation and subsequently tested the best configuration in 49 additional patients to determine the subcutaneous defibrillation thresh old in comparison with that of the standard transvenous ICD. Then we evaluated the longterm use of subcutaneous ICDs in a pilot study, involving 6 patients, which was followed by a trial involving 55 patients. RESULTS: The best device configuration consisted of a parasternal electrode and a left lateral thoracic pulse generator. This configuration was as effective as a transvenous ICD for terminating induced ventricular fibrillation, albeit with a significantly higher mean (±SD) energy requirement (36.6±19.8 J vs. 11.1±8.5 J). Among patients who received a permanent subcutaneous ICD, ventricular fibrillation was successfully detected in 100% of 137 induced episodes. Induced ventricular fibrillation was converted twice in 58 of 59 patients (98%) with the delivery of 65J shocks in two consecutive tests. Clinically significant adverse events included two pocket infections and four lead revisions. After a mean of 10±1 months, the device had successfully detected and treated all 12 episodes of spontaneous, sustained ventricular tachyarrhythmia. CONCLUSIONS: In small, nonrandomized studies, an entirely subcutaneous ICD consistently detected and converted ventricular fibrillation induced during electrophysiological testing. The device also successfully detected and treated all 12 episodes of spontaneous, sustained ventricular tachyarrhythmia. (Clin

The kinetic parameters of the reduction of barium sulphate to barium sulphide using carbon monoxide fractions of 2.4–9.6% and temperatures of 850–1000 °C, using an isothermal thermogravimetric method, were obtained. This reaction has shown to be temperature and carbon monoxide concentration dependent. By variation in temperature, at constant CO fractions, an average activation energy of 149 (±10) kJ/mol was observed. By changing the CO fraction at constant temperature, it is suggested that the reduction reaction is first order in CO. An overall reaction rate equation is proposed

We present a tomographic cosmological weak lensing analysis of the HST COSMOS Survey. Applying our lensing-optimized data reduction, principal component interpolation for the ACS PSF, and improved modelling of charge-transfer inefficiency, we measure a lensing signal which is consistent with pure gravitational modes and no significant shape systematics. We carefully estimate the statistical uncertainty from simulated COSMOS-like fields obtained from ray-tracing through the Millennium Simulation. We test our pipeline on simulated space-based data, recalibrate non-linear power spectrum corrections using the ray-tracing, employ photometric redshifts to reduce potential contamination by intrinsic galaxy alignments, and marginalize over systematic uncertainties. We find that the lensing signal scales with redshift as expected from General Relativity for a concordance LCDM cosmology, including the full cross-correlations between different redshift bins. For a flat LCDM cosmology, we measure sigma_8(Omega_m/0.3)^0.51=0.75+-0.08 from lensing, in perfect agreement with WMAP-5, yielding joint constraints Omega_m=0.266+0.025-0.023, sigma_8=0.802+0.028-0.029 (all 68% conf.). Dropping the assumption of flatness and using HST Key Project and BBN priors only, we find a negative deceleration parameter q_0 at 94.3% conf. from the tomographic lensing analysis, providing independent evidence for the accelerated expansion of the Universe. For a flat wCDM cosmology and prior w in [-2,0], we obtain w<-0.41 (90% conf.). Our dark energy constraints are still relatively weak solely due to the limited area of COSMOS. However, they provide an important demonstration for the usefulness of tomographic weak lensing measurements from space. (abridged), Comment: 26 pages, 25 figures, matches version accepted for publication by Astronomy and Astrophysics

Combining redshift and galaxy shape information offers new exciting ways of exploiting the gravitational lensing effect for studying the large scales of the cosmos. One application is the three-dimensional reconstruction of the matter density distribution which is explored in this paper. We give a generalisation of an already known minimum-variance estimator of the 3-D matter density distribution that facilitates the combination of thin redshift slices of sources with samples of broad redshift distributions for an optimal reconstruction. We show how, in principle, intrinsic alignments of source ellipticities or shear/intrinsic alignment correlations can be accommodated, albeit these effects are not the focus of this paper. We describe an efficient and fast way to implement the estimator on a contemporary desktop computer. Analytic estimates for the noise and biases in the reconstruction are given. The bias -- a spread and shift of structures in radial direction -- can be expressed in terms of a radial PSF, comprising the limitations of the reconstruction due to source shot-noise and the unavoidably broad lensing kernel. We conclude that a 3-D mass-density reconstruction on galaxy cluster scales is feasible but, for foreseeable surveys, a map with a S/N>~3 threshold is limited to structures with M200>~10^14 Msol/h, or 7x10^14 Msol/h, at low to moderate redshifts (z=0.1 or 0.6). However, we find that a heavily smoothed full-sky map of the very large-scale density field may also be possible as the S/N of reconstructed modes increases towards larger scales. Future improvements of the method can be obtained by including higher-order lensing information (flexion) which could also be implemented into our algorithm. [ABRIDGED], Comment: 22 pages, 13 figures, accepted by MNRAS