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In most of the worlds' distinct cultures, children – from toddlerhood – eagerly volunteer to help others with their chores. Laboratory research in child psychology supports the claim that the helper “stage” is biologically based. This Element examines the development of helping in varied cultural contexts, in particular, reviewing evidence for supportive environments in the ethnographic record versus an environment that extinguishes the drive to be helpful in WEIRD children. In the last section, the benefits of the helper stage are discussed, specifically the development of an ability to work and learn collaboratively.
This paper studies the Cascajal Block, a serpentinite artifact with an Olmec text dating to ca. 1000–900 b.c. (Rodríguez Martínez et al. 2006a). It introduces a new line drawing made possible by the detailed documentation carried out by Carrasco and Englehardt, presents a distributional analysis of the inscription in order to assess the sign inventory proposed by Rodríguez Martínez et al. (2006a) and revised by Mora-Marín (2009), and, most significantly, suggests that certain irregularities in the patterns of sign co-occurrence raised by previous authors (Justeson 2012; Macri 2006) are consistent with spelling practices in logosyllabic scripts, showing that the script is linguistically motivated. The work by Carrasco and Englehardt (2015) on the identification and analysis of sign pairings as likely diphrastic kennings is highlighted as crucial to establishing semantic controls needed for any attempt at decipherment; a new, repeated pairing is proposed, consisting of the PELT-PAW signs. Finally, this paper assesses how the various models for the reading formatting and direction of the text could impact the proposed hypotheses.
Introduced species can have strong ecological, social and economic effects on their non-native environment. Introductions of megafaunal species are rare and may contribute to rewilding efforts, but they may also have pronounced socio-ecological effects because of their scale of influence. A recent introduction of the hippopotamus Hippopotamus amphibius into Colombia is a novel introduction of a megaherbivore onto a new continent, and raises questions about the future dynamics of the socio-ecological system into which it has been introduced. Here we synthesize current knowledge about the Colombian hippopotamus population, review the literature on the species to predict potential ecological and socio-economic effects of this introduction, and make recommendations for future study. Hippopotamuses can have high population growth rates (7–11%) and, on the current trajectory, we predict there could be 400–800 individuals in Colombia by 2050. The hippopotamus is an ecosystem engineer that can have profound effects on terrestrial and aquatic environments and could therefore affect the native biodiversity of the Magdalena River basin. Hippopotamuses are also aggressive and may pose a threat to the many inhabitants of the region who rely upon the Magdalena River for their livelihoods, although the species could provide economic benefits through tourism. Further research is needed to quantify the current and future size and distribution of this hippopotamus population and to predict the likely ecological, social and economic effects. This knowledge must be balanced with consideration of social and cultural concerns to develop appropriate management strategies for this novel introduction.
Disasters pose a documented risk to mental health, with a range of peri- and post-disaster factors (both pre-existing and disaster-precipitated) linked to adverse outcomes. Among these, increasing empirical attention is being paid to the relation between disasters and violence.
This study examined self-reported experiences of assault or violence victimisation among communities affected by high, medium, and low disaster severity following the 2009 bushfires in Victoria, Australia. The association between violence, mental health outcomes and alcohol misuse was also investigated.
Participants were 1016 adults from high-, medium- and low-affected communities, 3–4 years after an Australian bushfire disaster. Rates of reported violence were compared by areas of bushfire-affectedness. Logistic regression models were applied separately to men and women to assess the experience of violence in predicting general and fire-related post-traumatic stress disorder, depression and alcohol misuse.
Reports of experiencing violence were significantly higher among high bushfire-affected compared with low bushfire-affected regions. Analyses indicated the significant relationship between disaster-affectedness and violence was observed for women only, with rates of 1.0, 0 and 7.4% in low, medium and high bushfire-affected areas, respectively. Among women living in high bushfire-affected areas, negative change to income was associated with an increased likelihood of experiencing violence (odds ratio, 4.68). For women, post-disaster violence was associated with more severe post-traumatic stress disorder and depression symptoms.
Women residing within high bushfire-affected communities experienced the highest levels of violence. These post-disaster experiences of violence are associated with post-disaster changes to income and with post-traumatic stress disorder and depression symptoms among women. These findings have critical implications for the assessment of, and interventions for, women experiencing or at risk of violence post-disaster.
Upper Ordovician (Katian) strata of the Lake Simcoe region of Ontario record a spectacularly diverse and abundant echinoderm fauna known as the Brechin Lagerstätte. Despite recognition as the most taxonomically diverse Katian crinoid paleocommunity, the Brechin Lagerstätte has received relatively little taxonomic study since Frank Springer published his classic monograph on the “Kirkfield fauna” in 1911.
Using a new collection of exceptionally preserved material, we evaluate all dicyclic inadunate crinoids occurring in the Brechin Lagerstätte, which is predominantly comprised of cladids (Eucladida and Flexibilia). We document 15 species across 11 genera, including descriptions of two new genera and four new species. New taxa include Konieckicrinus brechinensis n. gen. n. sp., K. josephi n. gen. n. sp., Simcoecrinus mahalaki n. gen. n. sp., and Dendrocrinus simcoensis n. sp.
Although cladids are not commonly considered major components of the Early Paleozoic Crinoid Macroevolutionary Fauna, which is traditionally conceived as dominated by disparids and diplobathrid camerates, they are the most diverse major lineage of crinoids occurring in the Brechin Lagerstätte. This unexpected result highlights the important roles of specimen-based taxonomy and systematic revisions in the study of large-scale diversity patterns.
Measuring the elastic and plastic properties with nanoindentation is predicated on the indentation not fracturing the material. In this study, an unloading curve analysis is used to identify indentation-induced fracture in brittle molecular organic crystals to define conditions, where properties measurements are accurate, and for calculating the toughness. Single crystals of cyclotetramethylene tetranitramine (HMX) and idoxuridine were indented from 1 to 300 mN with indenter probes of varying acuity to identify fracture initiation loads. Idoxuridine displayed no fracture up to and at 100 mN, with fracture occurrence then seen at an increasing rate until every indentation made induced fracture at 300 mN. HMX displayed no fracture up to and at 4 mN, with fracture then occurring at an increasing rate until every sample fractured at 8 mN. The toughness of HMX and idoxuridine is ≈0.28 ≈ 0.4–0.5 MPa/m1/2, respectively.
Increasing weed control costs and limited herbicide options threaten vegetable crop profitability. Traditional interrow mechanical cultivation is very effective at removing weeds between crop rows. However, weed control within the crop rows is necessary to establish the crop and prevent yield loss. Currently, many vegetable crops require hand weeding to remove weeds within the row that remain after traditional cultivation and herbicide use. Intelligent cultivators have come into commercial use to remove intrarow weeds and reduce cost of hand weeding. Intelligent cultivators currently on the market such as the Robovator, use pattern recognition to detect the crop row. These cultivators do not differentiate crops and weeds and do not work well among high weed populations. One approach to differentiate weeds is to place a machine-detectable mark or signal on the crop (i.e., the crop has the mark and the weed does not), thereby facilitating weed/crop differentiation. Lettuce and tomato plants were marked with labels and topical markers, then cultivated with an intelligent cultivator programmed to identify the markers. Results from field trials in marked tomato and lettuce found that the intelligent cultivator removed 90% more weeds from tomato and 66% more weeds from lettuce than standard cultivators without reducing yields. Accurate crop and weed differentiation described here resulted in a 45% to 48% reduction in hand-weeding time per hectare.
Multiproxy analysis of two sediment cores recovered from lagos Morrenas 3C and Ditkebi, located in the páramo of Costa Rica's Chirripó National Park, was undertaken to develop multidecadal-scale reconstructions of late Holocene fire regimes for the region. Analysis of macroscopic charcoal and sediment geochemistry (C%, N%, δ13C, δ15N, and C/N ratios) documents periodic burning of the páramo in Chirripó National Park during the past ~1700 yr. The charcoal records provide evidence of high fire frequency between AD ~560 and 720 and between AD ~980 and 1230. Severe fire episodes are reflected by a rapid increase in the flux of carbon (C) and nitrogen (N) from the surrounding catchment because of the volatilization of páramo vegetation. Additionally, δ15N, which sharply increases following local fire events, captures postfire changes in nutrient loading and, likely, the decadal-scale rate of postfire recovery of páramo vegetation. The consistently high δ13C and C/N values observed between AD ~700 and 1100 suggest an expansion of Muhlenbergia, a native C4 grass growing near shore, suggesting that the interval between AD ~700 and 1100, broadly corresponding to the Terminal Classic Drought and Medieval Climate Anomaly, was characterized by a decrease in effective moisture and temperature.
Retinoblastoma is the most common primary intraocular tumor of childhood with >95% survival rates in the US. Traditional therapy for retinoblastoma often included enucleation (removal of the eye). While much is known about the visual, physical, and cognitive ramifications of enucleation, data are lacking about survivors' perception of how this treatment impacts overall quality of life.
Qualitative analysis of an open-ended response describing how much the removal of an eye had affected retinoblastoma survivors' lives and in what ways in free text, narrative form.
Four hundred and four retinoblastoma survivors who had undergone enucleation (bilateral disease = 214; 52% female; mean age = 44, SD = 11) completed the survey. Survivors reported physical problems (n = 205, 50.7%), intrapersonal problems (n = 77, 19.1%), social and relational problems (n = 98, 24.3%), and affective problems (n = 34, 8.4%) at a mean of 42 years after diagnosis. Three key themes emerged from survivors' responses; specifically, they (1) continue to report physical and intrapersonal struggles with appearance and related self-consciousness due to appearance; (2) have multiple social and relational problems, with teasing and bullying being prominent problems; and (3) reported utilization of active coping strategies, including developing more acceptance and learning compensatory skills around activities of daily living.
Significance of results
This study suggests that adult retinoblastoma survivors treated with enucleation continue to struggle with a unique set of psychosocial problems. Future interventions can be designed to teach survivors more active coping skills (e.g., for appearance-related issues, vision-related issues, and teasing/bullying) to optimize survivors' long-term quality of life.
The retention of meltwater in the accumulation area of the Greenland ice sheet and other Arctic ice masses buffers their contribution to sea level change. However, sustained warming also results in impermeable ice layers or ‘ice slabs’ that seal the underlying pore space. Here, we use a 1-D, physically based, high-resolution model to simulate the surface mass balance (SMB), percolation, refreezing, ice layer formation and runoff from across the high-elevation area of Devon Ice Cap, Canada, from 2001 to 2016. We vary the thickness of the ‘impermeable’ ice layer at which underlying firn becomes inaccessible to meltwater. Thick near-surface ice layers are established by an initial deep percolation, the formation of decimetre ice layers and the infilling of interleaving pore space. The cumulative SMB increases by 48% by varying impermeable layer thickness between 0.01 and 5 m. Within this range we identify narrower range (0.25–1 m) that can simulate both the temporal variability in SMB and the observed near-surface density structure. Across this range, cumulative SMB variation is limited to 6% and 45–49% of mass retention takes place within the annually replenished snowpack. Our results indicate cooler summers after intense mid-2000s warming have led to a partial replenishment of pore space.
Identification of individuals with clinically significant aggressive behavior is critical for the prevention and management of human aggressive behavior. A previous population-based taxometric study reported that the Diagnostic and Statistical Manual of Mental Disorders-4th Edition (DSM-IV) intermittent explosive disorder (IED) belongs to its own discrete class (taxon) rather than existing along a continuum.
This study sought to extend previous population-based findings in a clinical research sample of adults with DSM-5 IED (n = 346), adults with non-aggressive DSM-5 disorders (n = 293), and adults without any DSM-5 disorder (n = 174), using standardized assessments of DSM-5 diagnoses, aggression, and other related measures not available in past studies.
Analyses revealed a taxonic latent structure that overlapped with the DSM-5 diagnosis of IED. Within the sample, taxon group members had higher scores on a variety of measures of psychopathology than did the complement members of the sample. Comorbidity of other diagnoses with IED did not affect these results.
These findings support the proposition that DSM-5 IED represents a distinct behavioral disorder rather than the severe end of an aggressive behavior continuum.
Early behaviors that differentiate later biomarkers for psychopathology can guide preventive efforts while also facilitating pathophysiological research. We tested whether error-related negativity (ERN) moderates the link between early behavior and later psychopathology in two early childhood phenotypes: behavioral inhibition and irritability. From ages 2 to 7 years, children (n = 291) were assessed longitudinally for behavioral inhibition (BI) and irritability. Behavioral inhibition was assessed via maternal report and behavioral responses to novelty. Childhood irritability was assessed using the Child Behavior Checklist. At age 12, an electroencephalogram (EEG) was recorded while children performed a flanker task to measure ERN, a neural indicator of error monitoring. Clinical assessments of anxiety and irritability were conducted using questionnaires (i.e., Screen for Child Anxiety Related Disorders and Affective Reactivity Index) and clinical interviews. Error monitoring interacted with early BI and early irritability to predict later psychopathology. Among children with high BI, an enhanced ERN predicted greater social anxiety at age 12. In contrast, children with high childhood irritability and blunted ERN predicted greater irritability at age 12. This converges with previous work and provides novel insight into the specificity of pathways associated with psychopathology.
The diet of most adults is low in fish and, therefore, provides limited quantities of the long-chain, omega-3 fatty acids (LCn-3FAs), eicosapentaenoic and docosahexaenoic acids (EPA, DHA). Since these compounds serve important roles in the brain, we sought to determine if healthy adults with low-LCn-3FA consumption would exhibit improvements in neuropsychological performance and parallel changes in brain morphology following repletion through fish oil supplementation.
In a randomized, controlled trial, 271 mid-life adults (30–54 years of age, 118 men, 153 women) consuming ⩽300 mg/day of LCn-3FAs received 18 weeks of supplementation with fish oil capsules (1400 mg/day of EPA and DHA) or matching placebo. All participants completed a neuropsychological test battery examining four cognitive domains: psychomotor speed, executive function, learning/episodic memory, and fluid intelligence. A subset of 122 underwent neuroimaging before and after supplementation to measure whole-brain and subcortical tissue volumes.
Capsule adherence was over 95%, participant blinding was verified, and red blood cell EPA and DHA levels increased as expected. Supplementation did not affect performance in any of the four cognitive domains. Exploratory analyses revealed that, compared to placebo, fish oil supplementation improved executive function in participants with low-baseline DHA levels. No changes were observed in any indicator of brain morphology.
In healthy mid-life adults reporting low-dietary intake, supplementation with LCn-3FAs in moderate dose for moderate duration did not affect neuropsychological performance or brain morphology. Whether salutary effects occur in individuals with particularly low-DHA exposure requires further study.
A novel disinfectant studied using an EPA protocol demonstrated sustained antimicrobial activity (ie, 3–5 log10 reduction) in 5 minutes after 24 hours for Staphylococcus aureus, vancomycin-resistant Enterococcus, Candida auris, carbapenem-resistant Escherichia coli and antibiotic-susceptible E. coli, and Enterobacter spp. Only ∼2 log10 reduction occurred with carbapenem-resistant Enterobacter spp and K. pneumoniae, and antibiotic-susceptible K. pneumoniae.
Despite much excellent work on the social roles that mousikê played in antiquity, aesthetic taste has been too little studied: that is, the preferences that different individuals possessed, and the way in which these preferences can be understood to relate to different kinds of identities. In an attempt to tease out some of these preferences in the early Imperial period, this article discusses one of the richest, though under-studied, texts for such topics: namely, Plutarch's Quaestiones convivales (QC), which represents intellectuals engaging with Greek poetry and music in a variety of sympotic contexts. For these educated individuals, mousikê and taste in it are treated as an intrinsic aspect and component of imperial paideia.
Team Strategies and Tools to Enhance Performance and Patient Safety (TeamSTEPPS™) is a tested strategy for improving communication and climate in hospitals. It is a promising but untested tool among school-based mental health teams. We examined the psychometric properties of the TeamSTEPPS Teamwork Perceptions Questionnaire (T-TPQ) and Teamwork Attitudes Questionnaire (T-TAQ) among 167 school mental health team members. Team members worked for one of five agencies in 33 K-8 urban public schools. Exploratory factor analyses and descriptive data are presented. For both the T-TPQ and T-TAQ, a unitary factor structure best fit the data for this sample. The T-TPQ and T-TAQ were not significantly correlated with one another and total scores did not significantly differ by staff role. Agencies differed in T-TAQ results, and one agency had lower T-TAQ total scores relative to other agencies. Results suggest that the factor structures are different among school mental health teams than among other healthcare providers.
Analysis of human remains and a copper band found in the center of a Late Archaic (ca. 5000–3000 cal BP) shell ring demonstrate an exchange network between the Great Lakes and the coastal southeast United States. Similarities in mortuary practices suggest that the movement of objects between these two regions was more direct and unmediated than archaeologists previously assumed based on “down-the-line” models of exchange. These findings challenge prevalent notions that view preagricultural Native American communities as relatively isolated from one another and suggest instead that wide social networks spanned much of North America thousands of years before the advent of domestication.