Context:
Inadequate vitamin D status is common within elderly populations and may be implicated in the etiology of autoimmune disease and inflammation. Few studies have investigated the relationship ...between vitamin D status and age-related immune dysfunction in humans.
Objective:
The aim of this study was to investigate the association between vitamin D status and immune markers of inflammation in a large sample of older adults.
Design, Setting, and Participants:
An observational investigation of 957 Irish adults (>60 years of age) recruited in Northern Ireland (55°N latitude) as part of the Trinity Ulster Department of Agriculture aging cohort study.
Main Outcome Measure:
We measured serum 25-hydroxyvitamin D (25(OH)D) by liquid chromatography tandem mass spectrometry and serum cytokines IL-6, TNF-α, IL-10, and C-reactive protein (CRP) by ELISA.
Results:
Concentrations of IL-6, CRP, and the ratios of IL-6 to IL-10 and CRP to IL-10 were significantly higher in individuals with deficient (<25 nmol/L) serum 25(OH)D compared with those with sufficient (>75 nmol/L) status after adjustment for age, sex, and body mass index (P < .05). Vitamin D status was a significant predictor of the IL-6 to IL-10 cytokine ratio, and those participants defined as deficient were significantly more likely to have an IL-6 to IL-10 ratio >2:1 compared with those defined as sufficient.
Conclusions:
This study demonstrated significant associations between low vitamin D status and markers of inflammation (including the ratio of IL-6 to IL-10) within elderly adults. These findings suggest that an adequate vitamin D status may be required for optimal immune function, particularly within the older adult population.
ABSTRACT
The Andromeda Galaxy is home to the annually erupting recurrent nova (RN) M 31N 2008-12a (12a); the first nova found to host a nova super-remnant (NSR). An NSR is an immense structure ...surrounding a RN, created from many millions of eruptions sweeping up material in the local environment to form a shell tens of parsecs across. Theory has demonstrated that NSRs should be found around all recurrent novae (RNe), even those systems with long periods between eruptions. Befittingly, the second NSR was found around the Galactic classical (and long suspected recurrent) nova, KT Eridani. In this Paper, we aim to find more of these phenomena through conducting the first ever survey for NSRs in M 31 and the Large Magellanic Cloud (LMC). We find that the surroundings of fourteen RNe in M 31 as well as the surroundings of the four RNe in the LMC do not show any evidence of vast parsec-scale structures in narrow-band (H α and ${\rm S\, {\small II}}$) images, unlike the one clearly seen around 12a, and therefore conclude that observable NSRs are either rare structures, or they are too faint (or small) to be detected in our existing data sets. Yet, the NSR surrounding 12a would also likely to have been overlooked in our study if it were approximately one magnitude fainter. Searches for NSRs around other RNe ‘masquerading’ as classical novae may prove to be fruitful as would whole surveys of other Local Group galaxies.
ABSTRACT
A nova super-remnant (NSR) is an immense structure associated with a nova that forms when frequent and recurrent nova (RN) eruptions sweep up surrounding interstellar medium (ISM) into a ...high-density and distant shell. The prototypical NSR, measuring over 100 pc across, was discovered in 2014 around the annually erupting nova M 31N 2008-12a. Hydrodynamical simulations demonstrated that the creation of a dynamic NSR by repeated eruptions transporting large quantities of ISM is not only feasible but that these structures should exist around all novae, whether the white dwarf (WD) is increasing or decreasing in mass. But it is only the RN with the highest WD masses and accretion rates that should host observable NSRs. KT Eridani is, potentially, the eleventh RNe recorded in the Galaxy and is also surrounded by a recently unveiled H α shell tens of parsecs across, consistent with an NSR. Through modelling the nova ejecta from KT Eri, we demonstrate that such an observable NSR could form in approximately 50 000 yr, which fits with the proper motion history of the nova. We compute the expected H α emission from the KT Eri NSR and predict that the structure might be accessible to wide-field X-ray facilities.
The accretion of hydrogen onto a white dwarf star ignites a classical nova eruption
-a thermonuclear runaway in the accumulated envelope of gas, leading to luminosities up to a million times that of ...the Sun and a high-velocity mass ejection that produces a remnant shell (mainly consisting of insterstellar medium). Close to the upper mass limit of a white dwarf
(1.4 solar masses), rapid accretion of hydrogen (about 10
solar masses per year) from a stellar companion leads to frequent eruptions on timescales of years
to decades
. Such binary systems are known as recurrent novae. The ejecta of recurrent novae, initially moving at velocities of up to 10,000 kilometres per second
, must 'sweep up' the surrounding interstellar medium, creating cavities in space around the nova binary. No remnant larger than one parsec across from any single classical or recurrent nova eruption is known
, but thousands of successive recurrent nova eruptions should be capable of generating shells hundreds of parsecs across. Here we report that the most frequently recurring nova, M31N 2008-12a in the Andromeda galaxy (Messier 31 or NGC 224), which erupts annually
, is indeed surrounded by such a super-remnant with a projected size of at least 134 by 90 parsecs. Larger than almost all known remnants of even supernova explosions
, the existence of this shell demonstrates that the nova M31N 2008-12a has erupted with high frequency for millions of years.
ABSTRACT
The nova super-remnant (NSR) surrounding M 31N 2008-12a (12a), the annually erupting recurrent nova (RN), is the only known example of this phenomenon. As this structure has grown as a ...result of frequent eruptions from 12a, we might expect to see NSRs around other RNe; this would confirm the RN–NSR association and strengthen the connection between novae and type Ia supernovae (SN Ia) as NSRs centred on SN Ia provide a lasting, unequivocal signpost to the single degenerate progenitor type of that explosion. The only previous NSR simulation used identical eruptions from a static white dwarf (WD). In this Paper, we simulate the growth of NSRs alongside the natural growth/erosion of the central WD, within a range of environments, accretion rates, WD temperatures, and initial WD masses. The subsequent evolving eruptions create dynamic NSRs tens of parsecs in radius comprising a low-density cavity, bordered by a hot ejecta pile-up region, and surrounded by a cool high-density, thin, shell. Higher density environments restrict NSR size, as do higher accretion rates, whereas the WD temperature and initial mass have less impact. NSRs form around growing or eroding WDs, indicating that NSRs also exist around old novae with low-mass WDs. Observables such as X-ray and H α emission from the modelled NSRs are derived to aid searches for more examples; only NSRs around high accretion rate novae will currently be observable. The observed properties of the 12a NSR can be reproduced when considering both the dynamically grown NSR and photoionization by the nova system.
Abstract
New MMT/Hectospec spectroscopy centered on the galaxy cluster A2626 and covering a ∼1.8 deg
2
area out to
z
∼ 0.46 more than doubles the number of galaxy redshifts in this region. The ...spectra confirm four clusters previously identified photometrically. A2625, which was previously thought to be a close neighbor of A2626, is in fact much more distant. The new data show six substructures associated with A2626 and five more associated with A2637. There is also a highly collimated collection of galaxies and galaxy groups between A2626 and A2637 having at least three and probably four substructures. At larger scales, the A2626–A2637 complex is not connected to the Pegasus–Perseus filament.
Organic soils have low sorption capacities for phosphorus (P), and may pose a risk of P loss to water if P applications to these soils coincide with runoff events. Little is known about the magnitude ...of exports of P in overland flow following application of P fertiliser onto these soils, or on the influence of the frequency on P losses and persistence. The number of P fertiliser applications was surveyed across 39 commercial farms to assess current practice and inform the design of a rainfall runoff experiment to evaluate the effect of frequency of P applications on losses and persistence across time. Superphosphate (16% P) was applied in single (equivalent to 30 and 55 kg P ha−1 applied at day 0) and split (equivalent to 15 and 27.5 kg P ha−1 applied in two doses at days 0 and 55) applications to an organic soil inclined at a slope of 6% in a rainfall simulator experiment. The surface runoff of dissolved reactive phosphorus (DRP) was measured in controlled 30-min rainfall simulations conducted intermittently over an 85-day period. The DRP losses in surface runoff after the first rainfall event were 44.6 and 97.8 mg L−1 for single applications of 30 and 55 kg ha−1, respectively, and 13.3 and 21.8 mg L−1 for the same rates split in two doses, indicating that single P applications had disproportionately bigger impacts on losses than split applications. This supports the idea that frequent, but smaller, P applications can minimise the impact of fertilisation on waters. Dissolved reactive P concentrations remained significantly higher than those from the control samples until the end the experiment for almost all the P treatments, highlighting the long-lasting effects of added P and the elevated risk of P losses on organic soils. For climates with frequent rainfall events, which are likely to coincide with fertiliser applications, smaller but more frequent P applications can reduce the risk of P transfer as opposed to one single application.
•A farm survey indicated that 40% of organic soils receive one fertiliser application.•The survey showed that mineral soils receive high numbers of fertiliser applications.•Mineral fertiliser was the predominant form of fertiliser used on farms.•Rainfall simulators examined impact of fertiliser applications on P in runoff.•Frequent, small applications of fertiliser minimise the possibility of P loss.
The costimulatory receptor 4-1BB is expressed on activated immune cells, including activated T cells. Antibodies targeting 4-1BB enhance the proliferation and survival of antigen-stimulated T cells ...in vitro and promote CD8 T cell-dependent anti-tumor immunity in pre-clinical cancer models. We found that T regulatory (Treg) cells infiltrating human or murine tumors expressed high amounts of 4-1BB. Intra-tumoral Treg cells were preferentially depleted by anti-4-1BB mAbs in vivo. Anti-4-1BB mAbs also promoted effector T cell agonism to promote tumor rejection. These distinct mechanisms were competitive and dependent on antibody isotype and FcγR availability. Administration of anti-4-1BB IgG2a, which preferentially depletes Treg cells, followed by either agonistic anti-4-1BB IgG1 or anti-PD-1 mAb augmented anti-tumor responses in multiple solid tumor models. An antibody engineered to optimize both FcγR-dependent Treg cell depleting capacity and FcγR-independent agonism delivered enhanced anti-tumor therapy. These insights into the effector mechanisms of anti-4-1BB mAbs lay the groundwork for translation into the clinic.
Display omitted
•Anti-4-1BB IgG2a depletes intratumoral Treg cells; IgG1 promotes CD8 T cell function•The efficacy of anti-4-1BB mIgG1 and anti-4-1BB mIgG2a depends on different FcγRs•Optimal tumor therapy requires sequential anti-4-1BB IgG2a and IgG1 or PD-1 blockade•Hinge-engineered anti-4-1BB mIgG2a/h2B mAb harnesses both mechanisms of action
Buchan et al. reveal dual anti-tumor activities for antibodies to the co-stimulatory receptor 4-1BB, which depend on antibody isotype and FcγR availability. Sequential scheduling of anti-4-1BB and checkpoint blockade mAbs, and antibodies engineered to harness both Treg cell depleting and effector cell agonism properties show potent anti-tumor activity in preclinical models, laying the groundwork for translation into the clinic.
Context.
Galaxy clusters are some of largest structures in the universe. These very dense environments tend to be home to higher numbers of evolved galaxies than found in lower-density environments. ...It is well known that dense environments can influence the evolution of galaxies through the removal of the neutral gas (H
I
) reservoirs that fuel star formation. It is unclear which environment has a stronger effect: the local environment (i.e., the substructure within the cluster), or the cluster itself.
Aims.
Using the new H
I
data from the Westerbork Coma Survey, we explore the average H
I
content of galaxies across the cluster comparing galaxies that reside in substructure to those that do not.
Methods.
We applied the Dressler–Shectman test to our newly compiled redshift catalogue of the Coma cluster to search for substructure. With so few of the Coma galaxies directly detected in H
I
, we used the H
I
stacking technique to probe the average H
I
content below what can be directly detected.
Results.
Using the Dressler–Shectman test, we find 15 substructures within the footprint of the Westerbork Coma Survey. We compare the average H
I
content for galaxies within substructure to those not in substructure. Using the H
I
stacking technique, we find that those Coma galaxies not detected in H
I
are more than 10–50 times more H
I
deficient than expected, which supports the scenario of an extremely efficient and rapid quenching mechanism. By studying the galaxies that are not directly detected in H
I
, we also find Coma to be more H
I
deficient than previously thought.
Metrics are investigated to help assess the performance of wireless sensors in buildings. Wireless sensor networks present tremendous opportunities for energy savings and improvement in occupant ...comfort in buildings by making data about conditions and equipment more readily available. A key barrier to their adoption, however, is the uncertainty among users regarding the reliability of the wireless links through building construction. Tests were carried out that examined three performance metrics as a function of transmitter–receiver separation distance, transmitter power level, and obstruction type. These tests demonstrated, via the packet delivery rate, a clear transition from reliable to unreliable communications at different separation distances. While the packet delivery rate is difficult to measure in actual applications, the received signal strength indication correlated well with the drop in packet delivery rate in the relatively noise-free environment used in these tests. The concept of an equivalent distance was introduced to translate the range of reliability in open field operation to that seen in a typical building, thereby providing wireless system designers a rough estimate of the necessary spacing between sensor nodes in building applications. It is anticipated that the availability of straightforward metrics on the range of wireless sensors in buildings will enable more widespread sensing in buildings for improved control and fault detection.
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