An understanding of the climatic controls on precipitation
δ
18O is required to interpret isotopic records of paleoclimate and paleoaltimetry. However, variations in precipitation
δ
18O in time and ...space are only poorly known in northern Central America. To test the hypothesis that precipitation and surface water
δ
18O values are dominated by temporal and spatial amount effects, we analyzed
δ
18O in surface waters collected from Guatemala and Belize, and in precipitation from the Global Network for Isotopes in Precipitation database for Veracruz, Mexico, and San Salvador, El Salvador. Herein we show that the dominant controls on
δ
18O values of precipitation and surface waters are fairly simple. Temporally, the dominant control on precipitation
δ
18O values is the amount effect, whereby there is an inverse correlation between rainfall amount and
δ
18O. Precipitation
δ
18O values decrease by 1.24‰ per 100 mm increase of monthly rainfall. Spatially, only two variables – distance from the coast and mean catchment altitude – explain 84% of the surface water
δ
18O variability. Surface water
δ
18O values show an altitude effect of −
1.9 to −
2.4‰ km
−
1
and a continental effect of 0.69‰ per 100 km once corrected for altitude effects. A decrease in surface water
δ
18O by 3 to 4‰ from the Caribbean Sea to the Pacific Ocean is evident as an isotopic rain shadow on the Pacific slope. Our data also show that river waters in this humid tropical environment are good proxies for
δ
18O values of precipitation in northern Central America. The Guatemala/Belize surface water line is defined as
δD
=
8.0
×
δ
18O
+
8.7, which is similar to the meteoric water line at San Salvador of
δD
=
8.1
×
δ
18O
+
10.9. Spatial variability in
δ
18O values is interpreted to reflect 1) progressive rainout of Caribbean-sourced air masses upon traverse of Central America, and 2) the temperature-dependent equilibrium fractionation between vapor and condensate related to the altitude effect. The data show that the northeast trade winds are the dominant moisture source to Central America, mixing with Pacific-derived moisture west of the cordilleran divide.
Stomach content analysis (SCA) and more recently stable isotope analysis (SIA) integrated with isotopic mixing models have become common methods for dietary studies and provide insight into the ...foraging ecology of seabirds. However, both methods have drawbacks and biases that may result in difficulties in quantifying inter-annual and species-specific differences in diets. We used these two methods to simultaneously quantify the chick-rearing diet of Chinstrap (Pygoscelis antarctica) and Gentoo (P. papua) penguins and highlight methods of integrating SCA data to increase accuracy of diet composition estimates using SIA. SCA biomass estimates were highly variable and underestimated the importance of soft-bodied prey such as fish. Two-source, isotopic mixing model predictions were less variable and identified inter-annual and species-specific differences in the relative amounts of fish and krill in penguin diets not readily apparent using SCA. In contrast, multi-source isotopic mixing models had difficulty estimating the dietary contribution of fish species occupying similar trophic levels without refinement using SCA-derived otolith data. Overall, our ability to track inter-annual and species-specific differences in penguin diets using SIA was enhanced by integrating SCA data to isotopic mixing modes in three ways: 1) selecting appropriate prey sources, 2) weighting combinations of isotopically similar prey in two-source mixing models and 3) refining predicted contributions of isotopically similar prey in multi-source models.
The COVID-19 pandemic has increased healthcare workers' (HCWs) risk for posttraumatic stress disorder (PTSD). Although subthreshold PTSD symptoms (PTSS) are common and increase vulnerability for ...health impairments, they have received little attention. We examined the prevalence of subthreshold PTSS and their relationship to physical health symptoms and sleep problems among HCWs during the pandemic's second wave (01/21–02/21). Participants (N = 852; 63.1% male; Mage = 38.34) completed the Short-Form PTSD Checklist (SF-PCL), the Cohen-Hoberman Inventory of Physical Symptoms, and the PROMIS Sleep-Related Impairment-Short-Form 4a. We created three groups with the SF-PCL: scores ≥11 = probable PTSD (5.5%); scores between 1 and 10 = subthreshold PTSS (55.3%); scores of 0 = no PTSS (39.2%). After controlling for demographics, occupational characteristics, and COVID-19 status, HCWs with subthreshold PTSS experienced greater physical health symptoms and sleep problems than HCWs with no PTSS. While HCWs with PTSD reported the greatest health impairment, HCWs with subthreshold PTSS reported 88% more physical health symptoms and 36% more sleep problems than HCWs with no PTSS. Subthreshold PTSS are common and increase risk for health impairment. Interventions addressing HCWs' mental health in response to the COVID-19 pandemic must include subthreshold PTSS to ensure their effectiveness.
•Subthreshold PTSS impact over half of healthcare workers.•A dose-response relationship exists between PTSD status and health impairment.•Subthreshold PTSS linked to 88% more health symptoms/36% more sleep problems.
Recently, the US FDA and Association of American Feed Control Officials approved Black Soldier Fly larvae (BSFL) as a feed ingredient for poultry. The objectives of this work were 1) to evaluate the ...nutritional profile of BSFL oil and meal in laying hens, and 2) measure the impact of the BSFL treatments on hen performance and egg quality. In 2 experiments, BSFL oil and meal were fed to replicate hens from 43 to 47 wk and from 51 to 55 wk of age. The hens were fed isocaloric, isonitrogenous diets with 3 treatment levels of BSFL oil (1.5, 3, and 4.5%, Exp. 1) or BSFL meal (8, 16 and 24%, Exp. 2). Data were analyzed by one-factor ANOVA for the main effect of diet and Tukey's multiple comparison for mean separation when significant. Exp. 1 results suggest BSFL oil could readily substituted for soybean oil with commercial hens at inclusion levels up to 4.5%. ADFI, BW, egg production, FCR, and egg weight were not impacted by the oil treatments (P > 0.05). Yolk color among hens fed the BSFL oil was greater averaging 7.88 compared to 7.37 from Control hen eggs (P = 0.0001). Exp. 2 diet formulation replaced soybean oil and meal with BSFL meal, and some additional corn was used in the higher BSFL diets. Diet amino acid balance at the highest level of inclusion (24% BSFL meal) indicates arginine and tryptophan are limiting and ADFI, BW and egg production were reduced (P < 0.05). Egg production averaged 85.14% for the Control, 8 and 16% BSFL meal hens and was significantly greater than hens fed 24% meal at 77.01%. However, 8 and 16% BSFL meal levels had no negative impact on performance and were not significantly different than the Controls. Yolk color was again higher among the meal treatments compared to the control (P = 0.0351). These experiments indicate that BSFL oil and meal can be used as dietary energy, protein and amino acids for hen maintenance, egg production and yolk coloration, although there may be upper limits of dietary inclusion.
Unusual self‐assembly behavior is observed for a range of hydrophilic homopolymers. This self‐assembly behavior is contrary to the expected behavior of such hydrophilic polymers and instead mimics ...more commonly reported amphiphilic block copolymers. It is proposed that the unique combination of hydrophobic end groups at both the α and ω chain end accounts for this unusual self‐assembly behavior. Complex internal polymer micelles are spontaneously formed when hydrophilic homopolymer polyelectrolytes and neutral polymers (with a weight fraction of the hydrophobic end groups <10 wt%) are directly dissolved in water. The homopolymers, poly2‐(diethylamino)ethyl methacrylate, poly(N‐isopropylacrylamide), and poly(ethoxyethylacrylate) are synthesized by reversible addition–fragmentation chain‐transfer (RAFT) polymerization using S′‐1‐dodecyl‐(S′)‐(α,α′‐dimethyl‐α″‐acetic acid) trithiocarbonate (DDMAT) and its derivatives as chain transfer agents (CTAs). A range of polyelectrolyte homopolymers with different terminal groups are designed and synthesized, which under acidic aqueous solution direct the self‐assembly to form well‐defined nanostructures. This assembly behavior was also observed for neutral polymers, and it was determined that the structure of the hydrophobic end groups (and thus choice of RAFT CTA) are very important in facilitating this unusual self‐assembly behavior of hydrophilic homopolymers. It is proposed that the functionality of commonly used CTAs such as DDMAT, can affect the solution association of the resultant homopolymers and can in fact afford ABA′ type polymers, which can undergo self‐assembly to form higher‐order nanostructures.
The remarkable effect of end groups on the self‐assembly of RAFT hydrophilic homopolymers is explored. These hydrophobically end‐functionalized homopolymers assemble in solution to afford well‐defined aggregates, which are characterized by dynamic and static light scattering and transmission electron microscopy.
Cancer patients who are parents show concerns about their ability to parent following diagnosis, and their adolescent and young adult (AYA) children have a need for improved cancer communication ...within the family. However, psychosocial support for families affected by parental cancer is not routinely available. This study explores the implementation of the Parent Support Worker (PSW) role, as part of a new cross sector model of care to support parent patients, their partners, and AYA children.
Two PSWs, social workers and healthcare staff (n = 26) from three hospitals participated in audio-recorded, semi-structured interviews about implementation of the PSW role. Template Analysis and Normalization Process Theory were used to analyze the interviews. Data on PSW service activity and referrals of AYA to support from a community organization were analyzed using descriptive statistics.
Eleven themes categorized into enablers and barriers of implementation were identified. Regarding acceptability of the role, three enablers (social workers' understanding of the PSW role increasing, easy and prompt access of staff and parent patients to PSWs, satisfaction with the PSW role) and one barrier (communication related confusion and frustration about the PSW role) were identified. Additionally, three enablers (the PSW role fills gaps in parenting-focused support and continuity of care, the PSW role alleviates social workers' workload, negotiation helped to define responsibilities) and one barrier (fear of social work roles to be overtaken by PSWs) for appropriateness of the role were found. Finally, two enablers of feasibility of the role (PSWs and social workers co-managing the work, higher confidence from hospital staff to talk about children in the family) and one barrier (lack of systematic identification and referral processes) were identified. Across hospitals, the number of referrals of AYA children to the community organization increased between 2.7 and 12 times nine months post-introduction of the service.
Established in response to identified gaps in oncology care for parents with cancer, their partners and AYA children, a novel cross-sector model of care was acceptable, appropriate, and feasible. Barriers and enablers to implementation identified in this study need to be considered when designing and implementing similar services.
Stable isotope analyses of zooarchaeological material can be used to examine ecological variability in exploited species at centennial to millennial scales. Climate change is a notable driver of ...marine ecosystem change, although historical fishing is also likely to have impacted past marine systems. Fishing removes the oldest and largest individuals and may thereby result in shorter trophic pathways and reduced niche width of predatory fish species. In the current study we examine the trophic niche of Atlantic cod, haddock and Atlantic wolffish, in the last millennium using δ
C and δ
N values of bone collagen. We report a lower trophic level of Atlantic cod and haddock but higher level of wolffish in present times, following centuries at consistent and higher trophic levels of Atlantic cod. This results in a concurrent converging trophic niche of the demersal fish. We suggest that the current data set provides a valuable historical baseline facilitating interpretation of current variability in the trophic ecology of northern demersal fish.
This review aimed to (1) summarise the psychosocial needs of children/adolescents (0–18 years) with a parent with cancer across the illness trajectory (diagnosis to bereavement) and (2) evaluate ...existing interventions for this population. Medline, CINAHL, PsychInfo, EMBASE and Social Work s were systematically searched for articles published from 1985 to 2015. Of 98 full text articles retrieved, 12 reported on children's psychosocial needs, and 12 intervention studies were identified. Each article was appraised in accordance with the Mixed Method Appraisal Tool. Three factors emerged as critical to consider in future intervention development: (1) Children need age‐appropriate information about their parent's cancer; (2) Children require support communicating with parents, family members and health professionals and (3) Children need an environment where they feel comfortable sharing positive/negative emotions and can have their experiences normalised among peers. All intervention studies reported at least one positive outcome, however, only five reported significant improvements in child/family functioning based on validated quantitative measure/s. Variability in study design and quality, combined with considerable heterogeneity in intervention characteristics and outcome variables limited the conclusions, which could be drawn. Therefore, further carefully designed and scientifically evaluated interventions for children facing a parent's cancer diagnosis are clearly warranted.
To characterize the skin-associated fungal microbiota (mycobiota) in dogs, and to evaluate the influence of body site, individual dog or health status on the distribution of fungi, next-generation ...sequencing was performed targeting the internal transcribed spacer region. A total of 10 dogs with no history of skin disease were sampled at 10 distinct body sites consisting of haired and mucosal skin, and 8 dogs with diagnosed skin allergies were sampled at six body sites commonly affected by allergic disease. Analysis of similarities revealed that body site was not an influencing factor on membership or structure of fungal communities in healthy skin; however, the mucosal sites were significantly reduced in fungal richness. The mycobiota from body sites in healthy dogs tended to be similar within a dog, which was visualized in principle coordinates analysis (PCoA) by clustering of all sites from one dog separate from other dogs. The mycobiota of allergic skin was significantly less rich than that of healthy skin, and all sites sampled clustered by health status in PCoA. Interestingly, the most abundant fungi present on canine skin, across all body sites and health statuses, were Alternaria and Cladosporium—two of the most common fungal allergens in human environmental allergies.
The skin-associated fungal microbiota were characterized in healthy dogs and those with skin allergies using next-generation sequencing, and the authors identified significant influences of the dog and health status on the distribution and diversity of fungal communities.
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