The radio active galactic nucleus (AGN) feedback in X-ray cool cores has been proposed as a crucial ingredient in the evolution of baryonic structures. However, it has long been known that strong ...radio AGNs also exist in 'noncool core' clusters, which brings up the question whether an X-ray cool core is always required for the radio feedback. In this work, we present a systematic analysis of brightest cluster galaxies (BCGs) and strong radio AGNs in 152 groups and clusters from the Chandra archive. All 69 BCGs with radio AGN more luminous than 2 X 1023 W Hz-1 at 1.4 GHz are found to have X-ray cool cores. BCG cool cores can be divided into two classes: the large cool core (LCC) class and the corona class. Small coronae, easily overlooked at z > 0.1, can trigger strong heating episodes in groups and clusters, long before LCCs are formed. Strong radio outbursts triggered by coronae may destroy embryonic LCCs and thus provide another mechanism to prevent the formation of LCCs. However, it is unclear whether coronae are decoupled from the radio feedback cycles as they have to be largely immune to strong radio outbursts. Our sample study also shows the absence of groups with a luminous cool core while hosting a strong radio AGN, which is not observed in clusters. This points to a greater impact of radio heating on low-mass systems than clusters. Few L 1.4 GHz > 1024 W Hz-1 radio AGNs (~16%) host an L 0.5-10 keV > 1042 erg s-1 X-ray AGN, while above these thresholds, all X-ray AGNs in BCGs are also radio AGNs. As examples of the corona class, we also present detailed analyses of a BCG corona associated with a strong radio AGN (ESO 137-006 in A3627) and one of the faintest coronae known (NGC 4709 in the Centaurus cluster). Our results suggest that the traditional cool core/noncool core dichotomy is too simple. A better alternative is the cool core distribution function, with the enclosed X-ray luminosity or gas mass.
Galaxy groups are the least massive systems where the bulk of baryons begin to be accounted for. Not simply the scaled-down versions of rich clusters following self-similar relations, galaxy groups ...are ideal systems to study baryon physics, which is important for both cluster cosmology and galaxy formation. We review the recent observational results on the hot gas in galaxy groups. The first part of this paper is on the scaling relations, including x-ray luminosity, entropy, gas fraction, baryon fraction and metal abundance. Compared to clusters, groups have a lower fraction of hot gas around the center (e.g. r < r2500), but may have a comparable gas fraction at large radii (e.g. r2500 < r < r500). Better constraints on the group gas and baryon fractions require sample studies with different selection functions and deep observations at r > r500 regions. The hot gas in groups is also iron-poor at large radii (0.3r500-0.7 r500). The iron content of the hot gas within the central regions (r < 0.3r500) correlates with the group mass, in contrast to the trend of the stellar mass fraction. It remains to be seen where the missing iron in low-mass groups is. In the second part, we discuss several aspects of x-ray cool cores in galaxy groups, including their difference from cluster cool cores, radio AGN heating in groups and the cold gas in group cool cores. Because of the vulnerability of the group cool cores to radio AGN heating and the weak heat conduction in groups, group cool cores are important systems to test the AGN feedback models and the multiphase cool-core models. At the end of the paper, some outstanding questions are listed.
Summary
Clonostachys rosea is a promising saprophytic filamentous fungus that belongs to phylum Ascomycota. Clonostachys rosea is widespread around the world and exists in many kinds of habitats, ...with the highest frequency in soil. As an excellent mycoparasite, C. rosea exhibits strong biological control ability against numerous fungal plant pathogens, nematodes and insects. These behaviours are based on the activation of multiple mechanisms such as secreted cell‐wall‐degrading enzymes, production of antifungal secondary metabolites and induction of plant defence systems. Besides having significant biocontrol activity, C. rosea also functions in the biodegradation of plastic waste, biotransformation of bioactive compounds, as a bioenergy sources and in fermentation. This mini review summarizes information about the biology and various applications of C. rosea and expands on its possible uses.
We propose a novel method to constrain turbulence and bulk motions in massive galaxies, galaxy groups, and clusters, exploring both simulations and observations. As emerged in the recent picture of ...top-down multiphase condensation, hot gaseous halos are tightly linked to all other phases in terms of cospatiality and thermodynamics. While hot halos (∼107 K) are perturbed by subsonic turbulence, warm (∼104 K) ionized and neutral filaments condense out of the turbulent eddies. The peaks condense into cold molecular clouds (<100 K) raining in the core via chaotic cold accretion (CCA). We show that all phases are tightly linked in terms of the ensemble (wide-aperture) velocity dispersion along the line of sight. The correlation arises in complementary long-term AGN feedback simulations and high-resolution CCA runs, and is corroborated by the combined Hitomi and new Integral Field Unit measurements in the Perseus cluster. The ensemble multiphase gas distributions (from the UV to the radio band) are characterized by substantial spectral line broadening ( v,los 100-200 ) with a mild line shift. On the other hand, pencil-beam detections (as H i absorption against the AGN backlight) sample the small-scale clouds displaying smaller broadening and significant line shifts of up to several 100 (for those falling toward the AGN), with increased scatter due to the turbulence intermittency. We present new ensemble v,los of the warm H +N ii gas in 72 observed cluster/group cores: the constraints are consistent with the simulations and can be used as robust proxies for the turbulent velocities, in particular for the challenging hot plasma (otherwise requiring extremely long X-ray exposures). Finally, we show that the physically motivated criterion C tcool/teddy 1 best traces the condensation extent region and the presence of multiphase gas in observed clusters and groups. The ensemble method can be applied to many available spectroscopic data sets and can substantially advance our understanding of multiphase halos in light of the next-generation multiwavelength missions.
Motivated by the discovery of several pulsating, extremely low-mass white dwarfs (ELM WDs, mass M 0.18 M ) that likely have WD companions, this paper discusses binary formation models for these ...systems. ELM WDs are formed using angular momentum losses by magnetic braking. Evolutionary models are constructed using the Modules for Experiments in Stellar Astrophysics (MESA), with ELM WD progenitors in the range 1.0 Md/M 1.5 and WD companions in the range 0.4 Ma/M 0.9. A prescription to reduce magnetic braking for thin surface convection zones is included. Upon the thinning of the evolved donor envelope, the donor star shrinks out of contact and mass transfer (MT) ceases, revealing the ELM WD. Systems with low masses have previously been suggested as possible AM CVNs. Systems with high masses, up to the limit M 0.18 M at which shell flashes occur on the WD cooling track, tend to expand out to orbital periods Porb 15 hr. In between this range, ELM WDs may become pulsators both as pre-WDs and on the WD cooling track. Brickhill's criterion for convective mode driving is used to estimate the location of the blue edge of the g-mode instability strip. In the appendix, we show that the formation of an ELM WD by unstable MT or a common-envelope event is unlikely. Stable Roche-lobe overflow with conservative MT produces only M 0.2 M .
Spinocerebellar ataxia (SCA) comprises a large group of heterogeneous neurodegenerative disorders inherited in an autosomal dominant fashion. It is characterized by progressive cerebellar ataxia with ...oculomotor dysfunction, dysarthria, pyramidal signs, extrapyramidal signs, pigmentary retinopathy, peripheral neuropathy, cognitive impairment and other symptoms. It is classified according to the clinical manifestations or genetic nosology. To date, 40 SCAs have been characterized, and include SCA1–40. The pathogenic genes of 28 SCAs were identified. In recent years, with the widespread clinical use of next‐generation sequencing, the genes underlying SCAs, and the mutants as well as the affected phenotypes were identified. These advances elucidated the phenotype–genotype relationship in SCAs. We reviewed the recent clinical advances, genetic features and phenotype–genotype correlations involving each SCA and its differentiation. The heterogeneity of the disease and the genetic diagnosis might be attributed to the regional distribution and clinical characteristics. Therefore, recognition of the phenotype–genotype relationship facilitates genetic testing, prognosis and monitoring of symptoms.
Abstract Background Programmed death-ligand 1 (PD-L1) expression has been suggested as a potential predictive biomarker of response to anti-PD-1/PD-L1 therapy. In this study, we investigated whether ...the expression of PD-L1 in tumour cells is affected by neoadjuvant concurrent chemoradiotherapy (CCRT) or chemotherapy in oesophageal squamous cell carcinoma. Patients and methods Between 2004 and 2014, we collected the medical records of locally advanced oesophageal cancer patients consecutively diagnosed and treated with neoadjuvant CCRT or chemotherapy, followed by curative resection. PD-L1 expression in acquired tissue specimens was evaluated by immunohistochemistry using the H-score. The changes in PD-L1 expression between paired samples were evaluated and we also analysed PD-L1 expression in surgical tumour specimens to evaluate its prognostic role. Results Twenty-eight paired tumour tissues that were acquired before and after neoadjuvant therapy were available: 19 patients with CCRT and 9 with chemotherapy before complete oesophagectomy. The PD-L1 H-score increased significantly from baseline tumour tissues to surgical tumour tissues after neoadjuvant CCRT ( P = 0.007, median H-score from 28 to 52), whereas it decreased significantly after neoadjuvant chemotherapy ( P = 0.048, median H-score from 53 to 22). In a total of 73 patients, including 45 additional cases for the prognosis analysis, patients with higher PD-L1 H-scores (≥20) had poorer overall survival (median 16.7 versus 32.9 months, P = 0.02) than those with lower H-scores (<20). Conclusions PD-L1 expression in tumour cells increased in oesophageal cancer patients who received neoadjuvant CCRT. Further studies with more cases are necessary to validate these findings.
Abstract Background The plasma protease factor XIa (FXIa) has become a target of interest for therapeutics designed to prevent or treat thrombotic disorders. Methods We used a solution-based, ...directed evolution approach called systematic evolution of ligands by exponential enrichment (SELEX) to isolate RNA aptamers that target the FXIa catalytic domain. Results Two aptamers, designated 11.16 and 12.7, were identified that bound to previously identified anion binding and serpin bindings sites on the FXIa catalytic domain. The aptamers were non-competitive inhibitors of FXIa cleavage of a tripeptide chromogenic substrate and of FXIa activation of factor IX. In normal human plasma, aptamer 12.7 significantly prolonged the aPTT clotting time. Conclusions The results show that novel inhibitors of FXIa can be prepared using SELEX techniques. RNA aptamers can bind to distinct sites on the FXIa catalytic domain and noncompetitively inhibit FXIa activity toward its primary macromolecular substrate factor IX with different levels of potency. Such compounds can be developed for use as therapeutic inhibitors.
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