The giant elliptical galaxy NGC 1275, at the centre of the Perseus cluster, is surrounded by a well-known giant nebulosity of emission-line filaments, which are plausibly in excess of 10(8) years ...old. The filaments are dragged out from the centre of the galaxy by radio-emitting 'bubbles' rising buoyantly in the hot intracluster gas, before later falling back. They act as markers of the feedback process by which energy is transferred from the central massive black hole to the surrounding gas. The mechanism by which the filaments are stabilized against tidal shear and dissipation into the surrounding extremely hot (4 x 10(7) K) gas has been unclear. Here we report observations that resolve thread-like structures in the filaments. Some threads extend over 6 kpc, yet are only 70 pc wide. We conclude that magnetic fields in the threads, in pressure balance with the surrounding gas, stabilize the filaments, so allowing a large mass of cold gas to accumulate and delay star formation.
Use of biomass is crucial for a sustainable supply of chemicals and fuels for future generations. Compared to fossil feedstocks, biomass is more functionalized and requires defunctionalisation to ...make it suitable for use. Deoxygenation is an important method of defunctionalisation. While thermal deoxygenation is possible, high energy input and lower reaction selectivity makes it less suitable for producing the desired chemicals and fuels. Catalytic deoxygenation is more successful by lowering the activation energy of the reaction, and when designed correctly, is more selective. Catalytic deoxygenation can be performed in various ways. Here we focus on decarboxylation and decarbonylation. There are several classes of catalysts: heterogeneous, homogeneous, bio- and organocatalysts and all have limitations. Homogeneous catalysts generally have superior selectivity and specificity but separation from the reaction is cumbersome. Heterogeneous catalysts are more readily isolated and can be utilised at high temperatures, however they have lower selectivity in complex reaction mixtures. While bio-catalysts can operate at ambient temperatures, the volumetric productivity is lower. Therefore it is not always apparent in advance which catalyst is the most suitable in terms of conversion and selectivity under optimal process conditions. Here we compare classes of catalysts for the decarboxylation and decarbonylation of biobased molecules and discuss their limitations and advantages. We mainly focus on the activity of the catalysts and find there is a strong correlation between specific activity (turn over frequency) and temperature for metal based catalysts (homogeneous or heterogeneous). Thus one is not more active than the other at the same temperature. Alternatively, enzymes have a higher turnover frequency but drawbacks (low volumetric productivity) should be overcome.
During decarboxylation and decarbonylation of biomass the activity of homogeneous and heterogeneous catalysts is mainly determined by temperature not by its nature; enzymes display higher activity.
The hot intra-cluster medium (ICM) permeating galaxy clusters and groups is not pristine, as it has been continuously enriched by metals synthesised in Type Ia (SNIa) and core-collapse (SNcc) ...supernovae since the major epoch of star formation (z ≃ 2–3). The cluster/group enrichment history and mechanisms responsible for releasing and mixing the metals can be probed via the radial distribution of SNIa and SNcc products within the ICM. In this paper, we use deep XMM-Newton/EPIC observations from a sample of 44 nearby cool-core galaxy clusters, groups, and ellipticals (CHEERS) to constrain the average radial O, Mg, Si, S, Ar, Ca, Fe, and Ni abundance profiles. The radial distributions of all these elements, averaged over a large sample for the first time, represent the best constrained profiles available currently. Specific attention is devoted to a proper modelling of the EPIC spectral components, and to other systematic uncertainties that may affect our results. We find an overall decrease of the Fe abundance with radius out to ~0.9 r500 and ~0.6 r500 for clusters and groups, respectively, in good agreement with predictions from the most recent hydrodynamical simulations. The average radial profiles of all the other elements (X) are also centrally peaked and, when rescaled to their average central X/Fe ratios, follow well the Fe profile out to at least ~0.5 r500. As predicted by recent simulations, we find that the relative contribution of SNIa (SNcc) to the total ICM enrichment is consistent with being uniform at all radii, both for clusters and groups using two sets of SNIa and SNcc yield models that reproduce the X/Fe abundance pattern in the core well. In addition to implying that the central metal peak is balanced between SNIa and SNcc, our results suggest that the enriching SNIa and SNcc products must share the same origin and that the delay between the bulk of the SNIa and SNcc explosions must be shorter than the timescale necessary to diffuse out the metals. Finally, we report an apparent abundance drop in the very core of 14 systems (~32% of the sample). Possible origins of these drops are discussed.
We present a new technique for choosing spatial regions for X-ray spectroscopy, called ‘contour binning’. The method chooses regions by following contours on a smoothed image of the object. In ...addition, we re-explore a simple method for adaptively smoothing X-ray images according to the local count rate, we term ‘accumulative smoothing’, which is a generalization of the method used by fadapt. The algorithms are tested by applying them to a simulated cluster data set. We illustrate the techniques by using them on a 50 ks Chandra observation of the Cassiopeia A supernova remnant. Generated maps of the object showing abundances in eight different elements, absorbing column density, temperature, ionization time-scale and velocity are presented. Tests show that contour binning reproduces surface brightness considerably better than other methods. It is particularly suited to objects with detailed spatial structure such as supernova remnants and the cores of galaxy clusters, producing aesthetically pleasing results.
One of the main effectors on the quality of life of living-kidney donors is postoperative fatigue. Caloric restriction (CR) and short-term fasting (STF) are associated with improved fitness and ...increased resistance to acute stress. CR/STF increases the expression of cytoprotective genes, increases immunomodulation via increased anti-inflammatory cytokine production, and decreases the expression of pro-inflammatory markers. As such, nutritional preconditioning by CR or STF represents a non-invasive and cost-effective method that could mitigate the effects of acute surgery-induced stress and postoperative fatigue. To investigate whether preoperative STF contributes to a reduction in fatigue after living-kidney donation, a randomized clinical trial is indicated.
We aim to determine whether 2.5 days of fasting reduces postoperative fatigue score in subjects undergoing living-kidney donation. In this randomized study, the intervention group will follow a preoperative fasting regime for 2.5 days with a low-dose laxative, while the control group will receive standard care. The main study endpoint is postoperative fatigue, 4 weeks after living-kidney donation. Secondary endpoints include the effect of preoperative fasting on postoperative hospital admission time, the feasibility of STF, and the postoperative recovery of donor and recipient kidney function. This study will provide us with knowledge of the feasibility of STF and confirm its effect on postoperative recovery.
Our study will provide clinically relevant information on the merits of caloric restriction for living-kidney donors and recipients. We expect to reduce the postoperative fatigue in living-kidney donors and improve the postoperative recovery of living-kidney recipients. It will provide evidence on the clinical merits and potential caveats of preoperative dietary interventions.
Netherlands Trial Register NL9262 . EudraCT 2020-005445-16 . MEC Erasmus MC MEC-2020-0778. CCMO NL74623.078.21.
Abstract
We present the first results from the Mapping Obscuration to Reionization with ALMA (MORA) survey, the largest Atacama Large Millimeter/submillimeter Array (ALMA) blank-field contiguous ...survey to date (184 arcmin
2
) and the only at 2 mm to search for dusty star-forming galaxies (DSFGs). We use the 13 sources detected above 5
σ
to estimate the first ALMA galaxy number counts at this wavelength. These number counts are then combined with the state-of-the-art galaxy number counts at 1.2 and 3 mm and with a backward evolution model to place constraints on the evolution of the IR luminosity function and dust-obscured star formation in the past 13 billion years. Our results suggest a steep redshift evolution on the space density of DSFGs and confirm the flattening of the IR luminosity function at faint luminosities, with a slope of
. We conclude that the dust-obscured component, which peaks at
z
≈ 2–2.5, has dominated the cosmic history of star formation for the past ∼12 billion years, back to
z
∼ 4. At
z
= 5, the dust-obscured star formation is estimated to be ∼35% of the total star formation rate density and decreases to 25%–20% at
z
= 6–7, implying a minor contribution of dust-enshrouded star formation in the first billion years of the universe. With the dust-obscured star formation history constrained up to the end of the epoch of reionization, our results provide a benchmark to test galaxy formation models, to study the galaxy mass assembly history, and to understand the dust and metal enrichment of the universe at early times.
In a 24‐month, multicenter, open‐label, randomized trial, 715 de novo kidney transplant recipients were randomized at 10–14 weeks to convert to everolimus (n = 359) or remain on standard calcineurin ...inhibitor (CNI) therapy (n = 356; 231 tacrolimus; 125 cyclosporine), all with mycophenolic acid and steroids. The primary endpoint, change in estimated glomerular filtration rate (eGFR) from randomization to month 12, was similar for everolimus versus CNI: mean (standard error) 0.3(1.5) mL/min/1.732 versus −1.5(1.5) mL/min/1.732 (p = 0.116). Biopsy‐proven acute rejection (BPAR) at month 12 was more frequent under everolimus versus CNI overall (9.7% vs. 4.8%, p = 0.014) and versus tacrolimus‐treated patients (2.6%, p < 0.001) but similar to cyclosporine‐treated patients (8.8%, p = 0.755). Reporting on de novo donor‐specific antibodies (DSA) was limited but suggested more frequent anti‐HLA Class I DSA under everolimus. Change in left ventricular mass index was similar. Discontinuation due to adverse events was more frequent with everolimus (23.6%) versus CNI (8.4%). In conclusion, conversion to everolimus at 10–14 weeks posttransplant was associated with renal function similar to that with standard therapy overall. Rates of BPAR were low in all groups, but lower with tacrolimus than everolimus.
In a multicenter, open‐label, randomized trial of de novo kidney transplant recipients, conversion to everolimus at 10–14 weeks posttransplant is associated with similar renal function as in patients who continue to standard tacrolimus or cyclosporine therapy, with low rates of biopsy‐proven acute rejection in all groups, but lower rates with tacrolimus than everolimus.
We report a genome-wide association study (GWAS) of major depressive disorder (MDD) in 1221 cases from the Sequenced Treatment Alternatives to Relieve Depression (STAR*D) study and 1636 screened ...controls. No genome-wide evidence for association was detected. We also carried out a meta-analysis of three European-ancestry MDD GWAS data sets: STAR*D, Genetics of Recurrent Early-onset Depression and the publicly available Genetic Association Information Network-MDD data set. These data sets, totaling 3957 cases and 3428 controls, were genotyped using four different platforms (Affymetrix 6.0, 5.0 and 500 K, and Perlegen). For each of 2.4 million HapMap II single-nucleotide polymorphisms (SNPs), using genotyped data where available and imputed data otherwise, single-SNP association tests were carried out in each sample with correction for ancestry-informative principal components. The strongest evidence for association in the meta-analysis was observed for intronic SNPs in ATP6V1B2 (P=6.78 x 10⁻⁷), SP4 (P=7.68 x 10⁻⁷) and GRM7 (P=1.11 x 10⁻⁶). Additional exploratory analyses were carried out for a narrower phenotype (recurrent MDD with onset before age 31, N=2191 cases), and separately for males and females. Several of the best findings were supported primarily by evidence from narrow cases or from either males or females. On the basis of previous biological evidence, we consider GRM7 a strong MDD candidate gene. Larger samples will be required to determine whether any common SNPs are significantly associated with MDD.
We make a further study of the very deep Chandra observation of the X‐ray brightest galaxy cluster, A 426 in Perseus. We examine the radial distribution of energy flux inferred by the ...quasi‐concentric ripples in surface brightness, assuming they are due to sound waves, and show that it is a significant fraction of the energy lost by radiative cooling within the inner 75–100 kpc, where the cooling time is 4–5 Gyr, respectively. The wave flux decreases outward with radius, consistent with energy being dissipated. Some newly discovered large ripples beyond 100 kpc, and a possible intact bubble at 170 kpc radius, may indicate a larger level of activity by the nucleus a few 100 Myr ago. The distribution of metals in the intracluster gas peaks at a radius of about 40 kpc and is significantly clumpy on scales of 5 kpc. The temperature distribution of the soft X‐ray filaments and the hard X‐ray emission component found within the inner 50 kpc are analysed in detail. The pressure due to the non‐thermal electrons, responsible for a spectral component interpreted as inverse Compton emission, is high within 40 kpc of the centre and boosts the power in sound waves there; it drops steeply beyond 40 kpc. We find no thermal emission from the radio bubbles; in order for any thermal gas to have a filling factor within the bubbles exceeding 50 per cent, the temperature of that gas has to exceed 50 keV.
Copy number variants (CNVs) have a major role in the etiology of autism spectrum disorders (ASD), and several of these have reached statistical significance in case-control analyses. Nevertheless, ...current ASD cohorts are not large enough to detect very rare CNVs that may be causative or contributory (that is, risk alleles). Here, we use a tiered approach, in which clinically significant CNVs are first identified in large clinical cohorts of neurodevelopmental disorders (including but not specific to ASD), after which these CNVs are then systematically identified within well-characterized ASD cohorts. We focused our initial analysis on 48 recurrent CNVs (segmental duplication-mediated 'hotspots') from 24 loci in 31 516 published clinical cases with neurodevelopmental disorders and 13 696 published controls, which yielded a total of 19 deletion CNVs and 11 duplication CNVs that reached statistical significance. We then investigated the overlap of these 30 CNVs in a combined sample of 3955 well-characterized ASD cases from three published studies. We identified 73 deleterious recurrent CNVs, including 36 deletions from 11 loci and 37 duplications from seven loci, for a frequency of 1 in 54; had we considered the ASD cohorts alone, only 58 CNVs from eight loci (24 deletions from three loci and 34 duplications from five loci) would have reached statistical significance. In conclusion, until there are sufficiently large ASD research cohorts with enough power to detect very rare causative or contributory CNVs, data from larger clinical cohorts can be used to infer the likely clinical significance of CNVs in ASD.
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