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Although research has shown that exposure to potentially traumatic and morally injurious events is associated with psychological symptoms among veterans, knowledge regarding functioning impacts remains limited.
A population-based sample of post-9/11 veterans completed measures of intimate relationship, health, and work functioning at approximately 9, 15, 21, and 27 months after leaving service. Moral injury, posttraumatic stress, and depression were assessed at ~9 months post-separation. We used Latent Growth Mixture Models to identify discrete classes characterized by unique trajectories of change in functioning over time and to examine predictors of class membership.
Veterans were assigned to one of four functioning trajectories: high and stable, high and decreasing, moderate and increasing, and moderate and stable. Whereas posttraumatic stress, depression, and moral injury associated with perpetration and betrayal predicted worse outcomes at baseline across multiple functioning domains, moral injury associated with perpetration and depression most reliably predicted assignment to trajectories characterized by relatively poor or declining functioning.
Moral injury contributes to functional problems beyond what is explained by posttraumatic stress and depression, and moral injury due to perpetration and depression most reliably predicted assignment to trajectories characterized by functional impairment over time.
Gene × environment (G × E) interactions in eating pathology have been increasingly investigated, however studies have been limited by sample size due to the difficulty of obtaining genetic data.
To synthesize existing G × E research in the eating disorders (ED) field and provide a clear picture of the current state of knowledge with analyses of larger samples.
Complete data from seven studies investigating community (n = 1750, 64.5% female) and clinical (n = 426, 100% female) populations, identified via systematic review, were included. Data were combined to perform five analyses: 5-HTTLPR × Traumatic Life Events (0–17 events) to predict ED status (n = 909), 5-HTTLPR × Sexual and Physical Abuse (n = 1097) to predict bulimic symptoms, 5-HTLPR × Depression to predict bulimic symptoms (n = 1256), and 5-HTTLPR × Impulsivity to predict disordered eating (n = 1149).
The low function (s) allele of 5-HTTLPR interacted with number of traumatic life events (P < .01) and sexual and physical abuse (P < .05) to predict increased likelihood of an ED in females but not males (Fig. 1). No other G × E interactions were significant, possibly due to the medium to low compatibility between datasets (Fig. 1).
Early promising results suggest that increased knowledge of G × E interactions could be achieved if studies increased uniformity of measuring ED and environmental variables, allowing for continued collaboration to overcome the restrictions of obtaining genetic samples.
Disclosure of interest
The authors have not supplied their declaration of competing interest.
Feed represents a substantial proportion of production costs in the dairy industry and is a useful target for improving overall system efficiency and sustainability. The objective of this study was to develop methodology to estimate the economic value for a feed efficiency trait and the associated methane production relevant to Canada. The approach quantifies the level of economic savings achieved by selecting animals that convert consumed feed into product while minimizing the feed energy used for inefficient metabolism, maintenance and digestion. We define a selection criterion trait called Feed Performance (FP) as a 1 kg increase in more efficiently used feed in a first parity lactating cow. The impact of a change in this trait on the total lifetime value of more efficiently used feed via correlated selection responses in other life stages is then quantified. The resulting improved conversion of feed was also applied to determine the resulting reduction in output of emissions (and their relative value based on a national emissions value) under an assumption of constant methane yield, where methane yield is defined as kg methane/kg dry matter intake (DMI). Overall, increasing the FP estimated breeding value by one unit (i.e. 1 kg of more efficiently converted DMI during the cow’s first lactation) translates to a total lifetime saving of 3.23 kg in DMI and 0.055 kg in methane with the economic values of CAD $0.82 and CAD $0.07, respectively. Therefore, the estimated total economic value for FP is CAD $0.89/unit. The proposed model is robust and could also be applied to determine the economic value for feed efficiency traits within a selection index in other production systems and countries.
In this cohort of Escherichia coli and Klebsiella spp hospital-onset bacteremia, isolated fluoroquinolone resistance had a larger relative impact on mortality than other phenotypic resistance patterns. This finding may support stewardship efforts targeting unnecessary fluoroquinolone use and increased attention from infection prevention and control departments.
Individual organisms on land and in the ocean sequester massive amounts of the carbon emitted into the atmosphere by humans. Yet the role of ecosystems as a whole in modulating this uptake of carbon is less clear. Here, we study several different mechanisms by which climate change and ecosystems could interact. We show that climate change could cause changes in ecosystems that reduce their capacity to take up carbon, further accelerating climate change. More research on – and better governance of – interactions between climate change and ecosystems is urgently required.
Eta Carinae is the most massive active binary within 10,000 light-years. While famous for the largest non-terminal stellar explosion ever recorded, observations reveal a supermassive (∼120 M⊙) binary consisting of an LBV and either a WR or extreme O star in a very eccentric orbit (e=0.9) with a 5.54-year period. Dramatic changes across multiple wavelengths are routinely observed as the stars move about in their highly elliptical orbits, especially around periastron when the hot (∼40 kK) companion star delves deep into the denser and much cooler (∼15 kK) extended wind photosphere of the LBV primary. Many of these changes are due to a dynamic wind-wind collision region (WWCR) that forms between the stars, plus expanding radiation-illuminated fossil WWCRs formed one, two, and three 5.54-year orbital cycles ago. These fossil WWCRs have been spatially and spectrally resolved by the Hubble Space Telescope/Space Telescope Imaging Spectrograph (HST/STIS) at multiple epochs, resulting in data cubes that spatially map Eta Carinae’s innermost WWCRs and follow temporal changes in several forbidden emission lines (e.g. [Fe iii] 4659 Å, [Fe ii] 4815 Å) across the 5.54-year cycle. We present initial results of 3D time-dependent hydrodynamical and radiative-transfer simulations of the Eta Carinae binary and its WWCRs with the goal of producing synthetic data cubes of forbidden emission lines for comparison to the available HST/STIS observations. Comparison of the theoretical models to the observations reveals important details about the binary’s orbital motion, photoionization properties, and recent (5–15year) mass loss history. Such an analysis also provides a baseline for following future changes in Eta Carinae, essential for understanding the late-stage evolution of a nearby supernova progenitor. Our modeling methods can also be adapted to a number of other colliding wind binary systems (e.g. WR 140) that are scheduled to be studied with future observatories (e.g. the James Webb Space Telescope).
Ion flow in charged nanopores is strongly influenced by the ratio of the Debye length to the pore radius. We investigate the asymptotic behaviour of solutions to the Poisson–Nernst–Planck (PNP) system in narrow pore like geometries and study the influence of the pore geometry and surface charge on ion transport. The physical properties of real pores motivate the investigation of distinguished asymptotic limits, in which either the Debye length and pore radius are comparable or the pore length is very much greater than its radius This results in a quasi-one-dimensional (1D) PNP model, which can be further simplified, in the physically relevant limit of strong pore wall surface charge, to a fully 1D model. Favourable comparison is made to the two-dimensional (2D) PNP equations in typical pore geometries. It is also shown that, for physically realistic parameters, the standard 1D area averaged PNP model for ion flow through a pore is a very poor approximation to the (real) 2D solution to the PNP equations. This leads us to propose that the quasi-1D PNP model derived here, whose computational cost is significantly less than 2D solution of the PNP equations, should replace the use of the 1D area averaged PNP equations as a tool to investigate ion and current flows in ion pores.
This study aimed to compare the quality of beef from suckler bulls raised on a high-energy concentrate ration and slaughtered at different carcass weights (CW)/ages. In total, 42 spring-born, Charolais and Limousin-sired, weaned suckler bulls were provided with a finishing diet of ad libitum concentrates and grass silage until they reached target CW of 340, 380 and 420 kg. Intramuscular fat (IMF) content tended (P<0.06) to be higher for 420 kg CW than for 380 and 340 kg CW. Sensory tenderness was lower (P<0.001) for 420 kg CW than for 380 and 340 kg CW. Juiciness was higher (P<0.05) for 420 kg CW than for 380 kg CW. Flavour liking was higher (P<0.05) for 420 and 380 kg CW (which did not differ) than for 340 kg CW. Overall, an increase in CW resulted in a slight increase in IMF content which could be responsible for the increase in juiciness and flavour liking of the beef. An increase in CW led to a decrease in the tenderness of the beef even though the overall liking of the beef was not affected.
In grass-based beef production systems (PS), early maturing (EM) breed types may be preferable to late maturing (LM) breed types in achieving adequate carcass fat cover. Biochemical and organoleptic characteristics of muscle from suckler bulls were investigated in EM and LM (n=28/breed) assigned to one of two PS (ad libitum concentrates and grass silage to slaughter (C) or ad libitum silage plus 2 kg concentrate daily during winter followed by 99 days at pasture and then an indoor finishing period on C (GSPC)) in a 2 breed type×2 PS factorial arrangement of treatments. Bulls were managed to have a common target carcass weight of 380 kg. Intramuscular fat (IMF) content was higher (P<0.05) for EM than LM, and for C than GSPC bulls. Collagen solubility was higher (P<0.05) for C than GSPC bulls. Lactate dehydrogenase (LDH) and phosphofructokinase activities were higher (P<0.05) for LM than EM. Isocitrate dehydrogenase activity and the Type I myosin heavy chain (MyHC) proportion were higher (P<0.05) for EM than LM. The LDH activity and the Type IIX MyHC proportion were higher (P<0.05) for C than GSPC bulls. Sensory ratings for tenderness and juiciness were higher (P<0.01) for beef from EM than LM while sensory ratings for tenderness, flavour liking and overall liking were higher (P<0.001) for C than for GSPC bulls. Differences in sensory quality were largely eliminated when adjusted for IMF. Overall, carcass fat scores, IMF and sensory scores were higher in EM than LM and in C than GSPC bulls but most differences in sensory quality could be attributed to differences in IMF.
Eta Carinae is one of the most massive observable binaries. Yet determination of its orbital and physical parameters is hampered by obscuring winds. However the effects of the strong, colliding winds changes with phase due to the high orbital eccentricity. We wanted to improve measures of the orbital parameters and to determine the mechanisms that produce the relatively brief, phase-locked minimum as detected throughout the electromagnetic spectrum. We conducted intense monitoring of the He ii λ4686 line in η Carinae for 10 months in the year 2014, gathering ~300 high S/N spectra with ground- and space-based telescopes. We also used published spectra at the FOS4 SE polar region of the Homunculus, which views the minimum from a different direction. We used a model in which the He ii λ4686 emission is produced by two mechanisms: a) one linked to the intensity of the wind-wind collision which occurs along the whole orbit and is proportional to the inverse square of the separation between the companion stars; and b) the other produced by the ‘bore hole’ effect which occurs at phases across the periastron passage. The opacity (computed from 3D SPH simulations) as convolved with the emission reproduces the behavior of equivalent widths both for direct and reflected light. Our main results are: a) a demonstration that the He ii λ4686 light curve is exquisitely repeatable from cycle to cycle, contrary to previous claims for large changes; b) an accurate determination of the longitude of periastron, indicating that the secondary star is ‘behind’ the primary at periastron, a dispute extended over the past decade; c) a determination of the time of periastron passage, at ~4 days after the onset of the deep light curve minimum; and d) show that the minimum is simultaneous for observers at different lines of sight, indicating that it is not caused by an eclipse of the secondary star, but rather by the immersion of the wind-wind collision interior to the inner wind of the primary.
ι Orionis is a massive binary system consisting of O9III + B1 III/IV stars. Though the system has been well studied, much about its fundamental properties have been difficult to determine. In this paper we report on the discovery of the heartbeat phenomenon in ι Orionis making it the most massive heartbeat system currently known. Using this phenomenon we have found empirical values for the masses and radii of both components. Moreover, we report the detection of tidally induced oscillations in an O-type star for the first time. These discoveries open a new avenue for exploring asteroseismology in massive stars.
Bull beef production is traditionally based on high concentrate rations fed indoors. Inclusion of grazed grass, which is generally a cheaper feed, would decrease the cost of bull beef production, but may affect beef quality. Accordingly, the organoleptic quality and composition of beef from continental-sired suckler bulls (n=126) assigned to either ad libitum concentrates to slaughter (C), grass silage (GS) ad libitum for 120 days followed by C (GSC) or GS followed by 100 days at pasture and then C (GSPC) and slaughtered at target carcass weights (CW) of 360, 410 or 460 kg was examined. Tenderness, flavour liking and overall liking were lower (P<0.05) for GSPC than for C and GSC. Intramuscular fat content and soluble collagen proportion were lower (P<0.05) for GSPC than GSC which was lower (P<0.05) than C. Soluble collagen proportion was lower (P<0.05) for 460 kg than 410 kg CW, which was lower (P<0.05) than 360 kg CW. Inclusion of a grazing period decreased the ratings of tenderness, flavour liking and overall liking, but age of the bulls at slaughter had no clear influence on sensory characteristics.
The synthetic auxin herbicides, aminocyclopyrachlor and clopyralid, control dicotyledonous weeds in turf. Clippings of turfgrass treated with synthetic auxin herbicides have injured off-target plants exposed to herbicide-laden clippings. Labels of aminocyclopyrachlor and clopyralid recommend that clippings of treated turfgrass remain on the turf following a mowing event. Alternative uses for synthetic auxin-treated turfgrass clippings are needed because large quantities of clippings on the turf surface interfere with the functionality and aesthetics of golf courses, athletic fields, and residential turf. A white clover bioassay was conducted to determine the persistence and bioavailability of aminocyclopyrachlor and clopyralid in turfgrass clippings. Aminocyclopyrachlor and clopyralid were each applied at 79 g ae ha−1 to mature tall fescue at 56, 28, 14, 7, 3.5, and 1.75 d before clipping collection (DBCC). Clippings were collected, and the treated clippings were recycled onto adjacent white clover plots to determine herbicidal persistence and potential for additional weed control. Clippings of tall fescue treated with aminocyclopyrachlor produced a nonlinear regression pattern of response on white clover. Calculated values for 50% response (GR50) for visual control, for normalized difference vegetative index (NDVI), and for reduction in harvested biomass were 20.5, 17.3, and 18.7 DBCC, respectively, 8 wk after clippings were applied. Clippings of tall fescue treated with clopyralid did not demonstrate a significant pattern for white clover control, presumably because clopyralid was applied at a less-than-label rate. The persistence and bioavailability of synthetic auxin herbicides in clippings harvested from previously treated turfgrass creates the opportunity to recycle clippings for additional weed control.
Lutein and zeaxanthin are xanthophyll carotenoids present in highly pigmented vegetables and fruits. Lutein is selectively accumulated in the brain relative to other carotenoids. Recent evidence has linked lutein to cognition in older adults, but little is known about lutein in young children, despite structural brain development. We determined lutein intake using FFQ, one 24 h recall and three 24 h recalls, plasma lutein concentrations and their association with cognition in 160 children 5·6–5·9 years of age, at low risk for neurodevelopmental delay. Plasma lutein was skewed, with a median of 0·23 (2·5th to 95th percentile range 0·11–0·53) µmol/l. Plasma lutein showed a higher correlation with lutein intake estimated as the average of three 24 h recalls (r 0·479; P = 0·001), rather than one 24 h recall (r 0·242; P = 0·003) or FFQ (r 0·316; P = 0·001). The median lutein intake was 697 (2·5th to 95th percentile range 178–5287) µg/d based on three 24 h recalls. Lutein intake was inversely associated with SFA intake, but dietary fat or SFA intakes were not associated with plasma lutein. No associations were found between plasma lutein or lutein intake and any measure of cognition. While subtle independent effects of lutein on child cognition are possible, separating these effects from covariates making an impact on both child diet and cognition may be difficult.
The rearing period has a key influence on the later performance of cattle, affecting future fertility and longevity. Producers usually aim to breed replacement heifers by 15 months to calve at 24 months. An age at first calving (AFC) close to 2 years (23 to 25 months) is optimum for economic performance as it minimises the non-productive period and maintains a seasonal calving pattern. This is rarely achieved in either dairy or beef herds, with average AFC for dairy herds usually between 26 and 30 months. Maintaining a low AFC requires good heifer management with adequate growth to ensure an appropriate BW and frame size at calving. Puberty should occur at least 6 weeks before the target breeding age to enable animals to undergo oestrous cycles before mating. Cattle reach puberty at a fairly consistent, but breed-dependent, proportion of mature BW. Heifer fertility is a critical component of AFC. In US Holsteins the conception rate peaked at 57% at 15 to 16 months, declining in older heifers. Wide variations in growth rates on the same farm often lead to some animals having delayed first breeding and/or conception. Oestrous synchronisation regimes and sexed semen can both be used but unless heifers have been previously well-managed the success rates may be unacceptably low. Altering the nutritional input above or below those needed for maintenance at any stage from birth to first calving clearly alters the average daily gain (ADG) in weight. In general an ADG of around 0.75 kg/day seems optimal for dairy heifers, with lower rates delaying puberty and AFC. There is some scope to vary ADG at different ages providing animals reach an adequate size by calving. Major periods of nutritional deficiency and/or severe calfhood disease will, however, compromise development with long-term adverse consequences. Infectious disease can also cause pregnancy loss/abortion. First lactation milk yield may be slightly lower in younger calving cows but lifetime production is higher as such animals usually have good fertility and survive longer. There is now extensive evidence that as long as the AFC is >23 months then future performance is not adversely influenced. On the other hand, delayed first calving >30 months is associated with poor survival. Underfeeding of young heifers reduces their milk production potential and is a greater problem than overfeeding. Farmers are more likely to meet the optimum AFC target of 23 to 25 months if they monitor growth rates and adjust feed accordingly.
Synthetic auxin herbicides are widely utilized in golf course settings for selective broadleaf weed control. Aminocyclopyrachlor (AMCP) is a newly registered pyrimidine carboxylic acid with similar chemical mode-of-action and structure to triclopyr (TRIC) and clopyralid (CLPY). Off-target injury on terrestrial plants has been documented following exposure to turfgrass clippings previously treated with TRIC and CLPY. Management practices on golf courses can distribute turfgrass clippings into water bodies; however, research has not evaluated the bioavailability of synthetic auxin residues from turfgrass clippings to aquatic and riparian plants within these environments. A bioassay study was conducted to determine the response of alligatorweed and parrotfeather to tall fescue clippings previously treated with synthetic auxin herbicides. Previously treated AMCP and TRIC + CLPY clippings were placed into growth containers mimicking a lentic system containing both alligatorweed and parrotfeather. Results indicated all herbicide treated clippings induced significant growth responses to alligatorweed and parrotfeather growth compared to a nontreated mulch and nontreated control. Alligatorweed control was greater from AMCP clippings treated 14, 7, 3, and 1 DBCC (49, 60, 90, and 80%, respectively) than comparative TRIC + CLPY clippings (33, 25, 37, and 64%, respectively) at 10 weeks after treatment (WAT). Parrotfeather control was greater from AMCP clippings (57 to 87%) than TRIC + CLPY clippings (9 to 63%) collected from all days before clipping collection (DBCC) timings when evaluated 6 WAT. At 10 WAT, greater parrotfeather control and shoot reduction was observed from AMCP than TRIC + CLPY clippings when treated 14, 7, and 3 DBCC. Based on these data, synthetic auxin residues can become bioavailable to aquatic and riparian plants within aqueous environments.