Super massive black holes at the centres of galaxies can cycle through periods of activity and quiescence. Characterising the duty cycle of active galactic nuclei (AGN) is crucial for understanding ...the impact of the energy they release on the host galaxy. For radio AGN, this can be done by identifying dying (remnant) and restarted radio galaxies from their radio spectral properties. Using the combination of the images at 1400 MHz produced by Apertif, the new phased-array feed receiver installed on the Westerbork Synthesis Radio Telescope, and images at 150 MHz provided by LOFAR, we have derived resolved spectral index images (at a resolution of ~15 arcsec) for all the sources within an approximately 6 deg
2
area of the Lockman Hole region. In this way, we were able to select 15 extended radio sources with emission (partly or entirely) characterised by extremely steep spectral indices (steeper than 1.2). These objects represent cases of radio sources in the remnant or the restarted phases of their life cycle. Our findings confirm that these objects are not as rare as previously thought, suggesting a relatively fast cycle. They also show a variety of properties that can be relevant for modelling the evolution of radio galaxies. For example, the restarted activity can occur while the remnant structure from a previous phase of activity is still visible. This provides constraints on the duration of the “off” (dying) phase. In extended remnants with ultra-steep spectra at low frequencies, the activity likely stopped a few hundred megayears ago, and they correspond to the older tail of the age distribution of radio galaxies, in agreement with the results of simulations of radio source evolution. We find remnant radio sources with a variety of structures (from double-lobed to amorphous), possibly suggesting different types of progenitors. The present work sets the stage for exploiting the powerful tool of low-frequency spectral index studies of extended sources by taking advantage of the large areas common to the LOFAR and the Apertif surveys.
We used wide-area surveys over 39 deg2 by the HerMES (Herschel Multi-tiered Extragalactic Survey) collaboration, performed with the Herschel
Observatory SPIRE multiwavelength camera, to estimate the ...low-redshift, 0.02 < z < 0.5, monochromatic luminosity functions (LFs) of galaxies at 250, 350 and 500 μm. Within this redshift interval, we detected 7087 sources in five independent sky areas, ∼40 per cent of which have spectroscopic redshifts, while for the remaining objects photometric redshifts were used. The SPIRE LFs in different fields did not show any field-to-field variations beyond the small differences to be expected from cosmic variance. SPIRE flux densities were also combined with Spitzer photometry and multiwavelength archival data to perform a complete spectral energy distribution fitting analysis of SPIRE detected sources to calculate precise k-corrections, as well as the bolometric infrared (IR; 8–1000 μm) LFs and their low-z evolution from a combination of statistical estimators. Integration of the latter prompted us to also compute the local luminosity density and the comoving star formation rate density (SFRD) for our sources, and to compare them with theoretical predictions of galaxy formation models. The LFs show significant and rapid luminosity evolution already at low redshifts, 0.02 < z < 0.2, with L
$_{\text{IR}}^{\ast } \propto (1+z)^{6.0\pm 0.4}$
and
$\Phi _{\text{IR}}^{\ast } \propto (1+z)^{-2.1\pm 0.4}$
, L
$_{250}^{\ast } \propto (1+z)^{5.3\pm 0.2}$
and
$\Phi _{250}^{\ast } \propto (1+z)^{-0.6\pm 0.4}$
estimated using the IR bolometric and the 250 μm LFs, respectively. Converting our IR LD estimate into an SFRD assuming a standard Salpeter initial mass function and including the unobscured contribution based on the UV dust-uncorrected emission from local galaxies, we estimate an SFRD scaling of SFRD0 + 0.08z, where SFRD0 ≃ (1.9 ± 0.03) × 10−2 M⊙ Mpc−3 is our total SFRD estimate at z ∼ 0.02.
Abstract
Immunotherapy by blockade of the PD-1/PD-L1 checkpoint demonstrated amazing tumor response in advanced cancer patients including head and neck squamous cell carcinoma (HNSCC). However, the ...majority of HNSCC patients still show little improvement or even hyperprogression. Irradiation is currently investigated as synergistic treatment modality to immunotherapy as it increases the number of T-cells thereby enhancing efficacy of immunotherapy. Apart from this immunogenic context a growing amount of data indicates that PD-L1 also plays an intrinsic role in cancer cells by regulating different cellular functions like cell proliferation or migration. Here, we demonstrate opposing membrane localization of PD-L1 in vital and apoptotic cell populations of radioresistant (RR) and radiosensitive (RS) HNSCC cell lines up to 72 h after irradiation using flow cytometry. Moreover, strong PD-L1 expression was found in nuclear and cytoplasmic cell fractions of RR. After irradiation PD-L1 decreased in nuclear fractions and increased in cytoplasmic fractions of RR cells. In contrast, RS cell lines did not express PD-L1, neither in the nucleus nor in cytoplasmic fractions. Additionally, overexpression of PD-L1 in RS cells led to a proportional increase of vital PD-L1 positive cells after irradiation. Moreover, co-immunoprecipitation experiments revealed an interaction between Akt-1 and PD-L1, mostly in irradiated RR cells compared to RS cells suggesting a differential influence of PD-L1 on cell signaling. In summary, our data imply the need for different therapeutic strategies dependent on the molecular context in which PD-L1 is embedded.
PD-L1 addresses different signaling axes in RS and RR cell lines depending on its localization. Cytoplasmic/nuclear location of Akt-1 binding PD-L1 might lead to enhanced survival and radioresistancy. In the future, combination therapies for tumor cells with different characteristics are required.
Purpose
The purpose of this study was to: (1) test the hypothesis that HTO improves articular cartilage composition in the medial compartment without adversely affecting the lateral compartment and ...patella, and; (2) explore associations between knee alignment and cartilage composition after surgery.
Methods
3T MRI and standing radiographs were obtained from 34 patients before and 1-year after HTO. Articular cartilage was segmented from T2 maps. Mechanical axis angle (MAA), posterior tibial slope, and patellar height were measured from radiographs. Changes in T2 and radiographic measures were assessed using paired
t
tests, and associations were assessed using Pearson correlation coefficients.
Results
The mean (SD) MAA before and after HTO was − 6.5° (2.4) and 0.6° (3.0), respectively. There was statistically significant shortening mean (95%CI) of T2 in the medial femur − 2.8 ms (− 4.2; − 1.3),
p
< 0.001 and medial tibia − 2.2 ms (− 3.3; − 1.0),
p
< 0.001, without changes in the lateral femur − 0.5 ms (− 1.6; 0.6),
p
= 0.3, lateral tibia 0.2 ms (− 0.8; 1.1),
p
= NS, or patella 0.5 ms (− 1.0; 2.1),
p
= NS). Associations between radiographic measures and T2 were low. 23% of the increase in lateral femur T2 was explained by postoperative posterior tibial slope (
r
= 0.48).
Conclusion
Performing medial opening wedge HTO without overcorrection improves articular cartilage composition in the medial compartment of the knee without compromising the lateral compartment or the patella. Although further research is required, these results suggest HTO is a disease structure-modifying treatment for knee OA.
PKS 1718−649 is one of the closest and most comprehensively studied candidates of a young active galactic nucleus (AGN) that is still embedded in its optical host galaxy. The compact radio structure, ...with a maximal extent of a few parsecs, makes it a member of the group of compact symmetric objects (CSO). Its environment imposes a turnover of the radio synchrotron spectrum towards lower frequencies, also classifying PKS 1718−649 as gigahertz-peaked radio spectrum (GPS) source. Its close proximity has allowed the first detection of extended X-ray emission in a GPS/CSO source with Chandra that is for the most part unrelated to nuclear feedback. However, not much is known about the nature of this emission. By co-adding all archival Chandra data and complementing these datasets with the large effective area of XMM-Newton, we are able to study the detailed physics of the environment of PKS 1718−649. Not only can we confirm that the bulk of the ≲kiloparsec-scale environment emits in the soft X-rays, but we also identify the emitting gas to form a hot, collisionally ionized medium. While the feedback of the central AGN still seems to be constrained to the inner few parsecs, we argue that supernovae are capable of producing the observed large-scale X-ray emission at a rate inferred from its estimated star formation rate.
To evaluate the desire for parenthood and reproductive outcomes of young cervical cancer survivors who underwent fertility-sparing surgery or fertility preservation procedures for invasive cervical ...cancer.
All women <45 years who underwent fertility-sparing treatment for invasive cervical cancer in a tertiary referral center in the Netherlands between January 2009 and January 2020 were identified. Fertility-sparing treatment options included Vaginal Radical Trachelectomy (VRT) for patients with early-stage disease and fertility preservation techniques (FP) when requiring Radical Hysterectomy (RH) or chemoradiotherapy. Data on reproductive intentions – and outcomes were retrieved from medical files and questionnaires.
75 patients were identified of whom 34 underwent VRT, 9 RH and 32 had (chemo)radiotherapy. 26 patients started FP of whom 23 (88.5%) successfully preserved fertility through cryopreservation of embryos, oocytes and ovarian tissue. After a median follow-up of 49 months, 5 patients developed recurrent disease and died. Reproductive outcomes were retrieved in 58 patients. 89.6% maintained their desire for parenthood after cancer treatment. Following VRT, we report a pregnancy rate of 61.9% among the patients attempting conception (n = 24). 15 patients conceived 21 pregnancies which resulted in 15 live-births, yielding a live-birth rate of 75.0%. Following RH or (chemo)radiotherapy, 3 surrogate pregnancies were established (21.4%) using frozen-thawed material with good neonatal outcomes.
Many cervical cancer survivors maintain the desire to become parents eventually. In early-stage disease, VRT shows good reproductive outcomes without compromising oncological safety. For those requiring gonadotoxic treatment fertility preservation and gestational surrogacy provides a promising alternative for achieving a biological offspring.
•The majority of cervical cancer survivors desiring fertility-sparing treatment, maintain their desire for parenthood after cancer treatment.•For patients with early-stage disease, vaginal radical trachelectomy shows good reproductive outcomes.•For patients requiring (chemo)radiotherapy, fertility preservation is successful in the majority of patients.•Gestational surrogacy with frozen-thawed material enables those without a (functional) uterus to have a genetic offspring.
Background
Anemia and hypoalbuminemia (HA) are acknowledged independent risk factors for morbidity and mortality in geriatric patients and are associated with nutritional status and frailty. Data ...exist regarding the association between albumin and frailty, anemia and frailty as well as frailty and nutritional status; however, there is a lack of information on the association between HA, anemia and nutritional status in older people.
Patients and methods
This study retrospectively analyzed 626 patients admitted to a German geriatrics department (average age 81.1 years, 68.2 % female and 31.8 % male) for anemia and HA. Data from the comprehensive geriatric assessment (CGA) and from the mini-nutritional assessment (MNA) were available in all patients.
Results
Patients with anemia suffered significantly more often from HA (
p
< 0.001) than patients without anemia, with an odds ratio (OR) of 1.99 (95 % confidence interval CI: 1.2-3.2) and of 5.41 (CI 95 %: 2.3-12.6) in patients at risk for malnutrition and in malnourished patients, respectively. A moderately significant association was seen between hemoglobin (Hb) and albumin values (Pearson’s correlation
r
= 0.330;
p
< 0.001) as well as between albumin values and the Barthel index (Spearman’s correlation
r
= 0.210;
p
< 0.001).
Conclusion
Anemia appears to be a risk factor for HA in inpatients with malnutrition and the observed association between albumin and Hb warrants further research. Geriatric inpatients with anemia should be evaluated in terms of the presence of malnutrition risk and HA.
Abstract
Delayed Hydride Cracking (DHC) is a failure mechanism that occurs in Zr alloys under certain conditions of hydrogen concentration, temperature and stress gradient. In service, hydrogen ...produced by corrosion reaction can be incorporated in Zr alloys and if the solid solubility is exceeded, hydrogen precipitates as zirconium hydride. The presence of a stress concentrator, such as a crack, generates the hydrogen diffusion and precipitation to the high stress zone beginning the DHC process. In this work, in-situ DHC tests in air at 250°C were performed at ANTARES, the neutron imaging facility of the FRM-II reactor. Samples of Zr2.5%Nb produced from extruded tubes and pressure tubes were studied using a stress rig specially modified to perform DHC tests in the neutron beam. H redistribution during mechanical testing was followed in-situ by registering the changes in neutron transmission. The results were compared with the images obtained by light optical microscopy after the tests. The results highlight the capabilities of neutron imaging to analyze time-dependent H distribution during DHC crack growth.
Abstract
Zirconium (Zr) alloys are widely used in nuclear power plants as fuel cladding and are susceptible to hydrogen (H) degradation. For long operational service, Zr-based components can suffer a ...mechanism known as Delayed Hydride Cracking (DHC) associated to an increase of the crack propagation velocity by the re-orientation and precipitation of Zr hydride. In this process, the H mobility has a great influence. In the present work, the isothermal diffusion of H in Zr-2.5%Nb specimens obtained from a CANDU pressure tube were studied at consecutive temperatures of 300°C, 350°C, 375°C and 400°C. H content and mobility were quantified by in-situ neutron imaging experiments performed on ANTARES, the cold neutron imaging facility of FRM II. The time evolution of the H concentration across the specimen allowed the determination of diffusion coefficients, and an assessment of the limitations of existing models commonly used to describe H diffusion.
Background
Given the demographic changes, the need for effective geriatric intervention is obvious. Geriatric care aims to maintain the highest possible level of independence and quality of life and ...to reduce the risk of need for care.
Objectives
This study investigated the benefits of geriatric care on functional performance, mobility and cognition.
Material and methods
This study involved a retrospective analysis of clinical data from 646 patients. At hospital admission and discharge functional status was assessed using the Barthel index. Mobility was evaluated by means of the Tinetti test and cognition by the mini-mental state examination (MMSE). A follow-up was conducted on 112 patients 2–5 months after hospital discharge. Statistical analysis included t-tests including Cohen's d for effect size and multivariate regression analysis.
Results
The mean age of the study population was 81.1 ± 7.1 years including 439 women (68 %) and 207 men (32 %). There were significant average improvements for activities of daily living (ADL), mobility and cognition comparing discharge and admission scores. For functional and mobility status, effect sizes were medium to high. Regression analyses showed that ADL improvement was predicted by functional, mobile and cognitive status at admission. Follow-up analyses revealed a high percentage of former patients still living at home and an overall maintenance of ADL levels.
Conclusion
Geriatric patients seem to experience long-term improvements during geriatric treatment, which appears to fulfill its aim of recovering independence. For a better understanding of relevant factors for the recreation of geriatric patients, further research is needed, e.g. with respect to the impact of the nutritional status.
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