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In recent years, researchers in pre-Hispanic Central America have used new approaches that greatly amplify and enhance evidence of plants and their uses. This paper presents a case study from Puerto Escondido, located in the lower Ulúa River valley of Caribbean coastal Honduras. We demonstrate the effectiveness of using multiple methods in concert to interpret ethnobotanical practice in the past. By examining chipped-stone tools, ceramics, sediments from artifact contexts, and macrobotanical remains, we advance complementary inquiries. Here, we address botanical practices “in the home,” such as foodways, medicinal practices, fiber crafting, and ritual activities, and those “close to home,” such as agricultural and horticultural practices, forest management, and other engagements with local and distant ecologies. This presents an opportunity to begin to develop an understanding of ethnoecology at Puerto Escondido, here defined as the dynamic relationship between affordances provided in a botanical landscape and the impacts of human activities on that botanical landscape.
Common bean (Phaseolus vulgaris L.) is perhaps the most important grain legume in sub-Saharan Africa (SSA) smallholder systems for food security and household income. Although a wide choice of varieties is available, smallholder farmers in western Kenya realize yields that are low and variable since they operate in risky production environments. Significant seasonal variations exist in rainfall and severity of pests and diseases. This situation is worsened by the low and declining soil fertility, coupled with low capacity of farmers to purchase production inputs such as fertilizers, fungicides and insecticides, and land scarcity. The objective of this study was to investigate whether growing multiple-bean varieties instead of a single variety can enable farmers enhance yield stability over seasons and ensure food security. Five common bean varieties were evaluated in multiple farms for 11 seasons at Kapkerer in Nandi County, western Kenya. Data were collected on grain yield, days to 50% flowering and major diseases. In addition, daily rainfall was recorded throughout the growing seasons. The five varieties were combined in all possible ways to create 31 single- and multiple-bean production strategies. The strategies were evaluated for grain yield performance and yield stability over seasons to determine the risk of not attaining a particular yield target. Results indicated that cropping multiple-bean varieties can be an effective way for reducing production risks in heterogeneous smallholder systems. Yield stability can be greatly enhanced across diverse environments, leading to improved food security, especially for the resource-poor smallholder farmers operating in risk-prone environments. Although the results show that some of the single-bean variety strategies were high yielding, their yield stability was generally lower than those of multiple strategies. Resource-poor risk averse farmers can greatly increase the probability of exceeding their yield targets by cropping multiple-bean varieties with relatively low yields but high grain yield stability. Trading-off high grain yield for yield stability might be an important strategy for minimizing bean production risks.
This study examined effects of risk factors in multiple domains measured in preschool and kindergarten on age 6 depression symptoms, and on changes in symptom levels between ages 4 and 6. Two models were examined in a large, diverse (N = 796) community sample of children and parents. Risk variables included SES, stress, conflict, parental depression, parental hostility, support, scaffolding, child negative affect (NA), effortful control (EC), sensory regulation (SR), and attachment security. Model 1 included effects of risk factors at ages 4 and 5 on child depression symptoms at age 6. Model 2 also included depression symptoms at all three ages to examine changes in these symptoms. Model 1 revealed that age 4 and 5 parental depression, NA, EC, and SR predicted age 6 child depression levels, Several age 4 variables had indirect pathways to age 6 depression via age 5 EC. Model 2 revealed that preschool depression was the only age 4 variable, and EC and SR were the only age 5 variables that significantly predicted increases in age 6 depression. These findings highlight the role of self-regulation in child depression and suggest that targeting self-regulation may be an effective prevention and intervention strategy.
This study examines factors associated with satisfaction with oral pills and injectables among past users in Kenya based on a baseline survey for the 2-year prospective longitudinal study Improving Measurement of Unintended Pregnancy and Unmet Need for Family Planning conducted in 2016. Married women aged 15–39 years were interviewed using a structured questionnaire that captured information on reproduction, contraceptive knowledge and beliefs and attitudes towards contraception in general and towards specific methods. A multivariate logistic regression analysis was used to examine factors that influenced satisfaction with oral pills and injectables among past users in one urban site (Nairobi slums) and one predominantly rural site (Homa Bay in western Kenya). Results showed that dissatisfaction with pills and injectables is common among past users in both rural and urban Kenya (ranging from 39% to 56%). The distinctive contribution of the study lies in its ability to relate method-specific beliefs to overall satisfaction. Perception of effectiveness, ease of use and safety for long-term use had statistically significant influences on satisfaction with pills in both urban and rural sites while partner’s approval was only important in Nairobi. For injectables, the perception of safety for long-term use was significant in the urban but not the rural site. Unlike pills, the belief that members of a woman’s social network had used a method and found it satisfactory was a particularly powerful influence on satisfaction (AOR=2.8 in rural and 3.2 in urban). Perception of accessibility and fears about infertility were not found to be statistically associated with satisfaction for either pills or injectables. Surprisingly, the effects of all perceived contraceptive attributes were the same for major socio-demographic strata of the populations. The findings underscore the need for targeted counselling and community-based communication interventions to address negative and erroneous perceptions about family planning methods.
The present study examined a cascade model of age 4 and 5 contextual, parent, parenting, and child factors on symptoms of oppositional defiant disorder (ODD) at age 6 in a diverse community sample of 796 children. Contextual factors include socioeconomic status, family stress, and conflict; parent factors included parental depression; parenting factors included parental hostility, support, and scaffolding skills; child factors included child effortful control (EC), negative affect (NA), and sensory regulation. Direct effects of age 5 conflict, hostility, scaffolding, EC, and NA were found. Significant indirect, cascading effects on age 6 ODD symptom levels were noted for age 4 socioeconomic status via age 5 conflict and scaffolding skills; age 4 parental depression via age 5 child NA; age 4 parental hostility and support via age 5 EC; age 4 support via age 5 EC; and age 4 attachment via age 5 EC. Parenting contributed to EC, and the age 5 EC effects on subsequent ODD symptom levels were distinct from age 5 parental contributions. Scaffolding and ODD symptoms may have a reciprocal relationship. These results highlight the importance of using a multidomain model to examine factors associated with ODD symptoms early in the child's grammar school years.
Health is an important aspect of individuals’ lives as they age. The aim of this study was to examine the relationship of sociodemographic factors, diagnosed chronic health conditions, and current depression with attitudes to aging in midlife.
A cross-sectional baseline analysis was conducted on the first 300 participants from the Canterbury Health, Ageing and Life Course study in New Zealand, a stratified randomized community longitudinal study of adults recruited between 49 and 51 years. Attitudes were measured using the Attitudes to Aging Questionnaire (AAQ) and analyzed with a range of prevalent diagnosed chronic conditions, current depression, and sociodemographic variables.
Individuals perceived their physical aging more negatively after a diagnosis of hypertension, arthritis or asthma. Diagnosed lifetime depression and anxiety, and current depression, showed strong relationships with attitudes to aging across domains. After controlling for sociodemographic factors and current depression, individuals with diagnosed hypertension, arthritis, asthma, lifetime depression or anxiety continued to report significantly more negative attitudes to aging. Current depression showed the strongest associations with attitudes to aging and mediated relationships of health on attitudes to aging.
Physical and mental health are related to attitudes to aging. Most chronic conditions examined are significantly associated with attitudes toward aging in the physical change domain. Diagnosed lifetime depression and anxiety, and current depression, are negatively related across attitudinal domains. Individuals can feel positive about aging while experiencing poorer health, but this is more difficult in the presence of low mood.
Paleoethnobotanical analyses of samples excavated at Los Naranjos, Honduras, provide an unprecedented record of the diversity of plants used at an early center with monumental architecture and sculpture dating between 1000 and 500 B.C. and contribute to understandings of early village life in Mesoamerica. Los Naranjos is the major site adjacent to Lake Yojoa, where analysis of an important pollen core suggests very early clearing of the landscape and shifts in the relative prevalence of certain plants over time, including increases in maize. Our results from starch grain, phytolith, and macrobotanical analysis complicate interpretation of previous pollen core dates, suggesting that maize was not as central as expected to the early inhabitants of the settlement. Moreover, with identification of macrobotanical remains recovered from flotation of sediments and extraction of microbotanical remains from adhering sediments and the surfaces of obsidian tools, we can compare the potential of each analysis in interpretations of plant use. No single method would have allowed recovery and identification of all the plants documented across sample types. The presence of botanical residues on the obsidian tools provides direct evidence of processing. Even in the small sample analyzed, we can recognize tools used exclusively for culinary processing, tools used only for non-culinary tasks, and multi-purpose tools.
We investigated an increase in Trichosporon asahii isolates among inpatients. We identified 63 cases; 4 involved disseminated disease. Trichosporon species was recovered from equipment cleaning rooms, washbasins, and fomites, which suggests transmission through washbasins. Patient washbasins should be single-patient use only; adherence to appropriate hospital disinfection guidelines was recommended.
Genetic factors can play a key role in the multiple level of analyses approach to understanding the development of child psychopathology. The present study examined gene–environment correlations and Gene × Environment interactions for polymorphisms of three target genes, the serotonin transporter gene, the D4 dopamine receptor gene, and the monoamine oxidase A gene in relation to symptoms of anxiety, depression, and oppositional behavior. Saliva samples were collected from 175 non-Hispanic White, 4-year-old children. Psychosocial risk factors included socioeconomic status, life stress, caretaker depression, parental support, hostility, and scaffolding skills. In comparison with the short forms (s/s, s/l) of the serotonin transporter linked polymorphic repeat, the long form (l/l) was associated with greater increases in symptoms of oppositional defiant disorder in interaction with family stress and with greater increases in symptoms of child depression and anxiety in interaction with caretaker depression, family conflict, and socioeconomic status. In boys, low-activity monoamine oxidase A gene was associated with increases in child anxiety and depression in interaction with caretaker depression, hostility, family conflict, and family stress. The results highlight the important of gene–environment interplay in the development of symptoms of child psychopathology in young children.
Ethnic variations have previously been identified in the duration of untreated psychosis (DUP) and pathways into psychiatric services. These have not been examined in the context of early intervention services, which may alter these trajectories.
To explore ethnic differences in the nature and duration of pathways into early intervention services.
In a naturalistic cohort study, data were collected for 1024 individuals with psychotic disorders accepted for case management by eight London early intervention services.
Duration of untreated psychosis was prolonged in the White British group compared with most other ethnic groups. White British individuals were more likely to make contact with their general practitioner and less likely to be seen within emergency medical services. All Black patient groups were more likely than their White British counterparts to experience involvement of criminal justice agencies.
Variations continue to exist in how and when individuals from different ethnic groups access early intervention services. These may account for disparities in DUP.
The electronic structure of delta plutonium (δ-Pu) and plutonium compounds is investigated using photoelectron spectroscopy (PES). Results for δ-Pu show a small component of the valence electronic structure which might reasonably be associated with a 5f6 configuration. PES results for PuTe are used as an indication for the 5f6 configuration due to the presence of atomic multiplet structure. Temperature dependent PES data on δ-Pu indicate a narrow peak centered 20 meV below the Fermi energy and 100 meV wide. The first PES data for PuCoIn5 indicate a 5f electronic structure more localized than the 5fs in the closely related PuCoGa5. There is support from the PES data for a description of Pu materials with an electronic configuration of 5f5 with some admixture of 5f6 as well as a localized/delocalized 5f5 description.
Many metallic actinide systems host partially filled 5f electrons in the low-energy spectrum. Consequently, they exhibit diverse quantum mechanical phenomena such as magnetism, superconductivity, a mysterious hidden-order phase, or heavy-fermion behavior. Here we present results of a unified theoretical method based on the self-consistent GW formalism for the electronic many-body self-energy. We calculate the dynamic electronic correlation spectra starting from materials specific first-principles electronic band-structure. In particular, we present results for four isostructural intermetallic actinides PuCoIn5, PuCoGa5, PuRhGa5, and UCoGa5. A common underlying property of these materials is a strong spin–orbit coupling split band structure that enables substantial spin fluctuations. In a feedback effect on the electronic structure they create electronic ‘hot spots’, where the single-particle spectral weight is maximum, resulting in a universal peak-dip-hump feature. These results are in good agreement with experiments, suggesting that actinides are adequately described by the intermediate Coulomb interaction regime, where both itinerant (peak) and localized (hump) features coexist.
The electronic structure of Pu materials is examined using photoelectron spectroscopy. For delta-phase Pu metal as well as PuCoGa5 and PuIn3, the 5f electrons appear to be at the threshold between localized and itinerant character. A mixed level model computational scheme is used which results in non-magnetic solutions for the electronic structure and agrees well with the photoemission measurements. Several other computational schemes are assessed against photoemission results for delta Pu. Additional insight is provided by O2 and H2 dosing of the delta Pu samples and consideration of surface effects. The experimental and computational results are consistent with the 5f electrons in Pu materials exhibiting a dual nature with some fraction of the 5f levels localized and not participating in the bonding while the other fraction of 5f character is involved in bonding and hybridization with the conduction electrons.
The 5f electronic states in elemental Pu and Pu compounds exhibit elements of both itinerant and localized behavior. Several first-principles calculations have been presented to describe this balance, differing in the manner in which electron correlation is included in the calculation. This paper describes a calculations performed with the Mixed Level Model (MLM), presenting calculated results for the two Pu compounds, PuRhGa5 and PuCoGa5. The MLM results are compared with other calculations and the differences discussed.
Optical and photoelectron spectroscopies using VUV and Soft X-ray photons are powerful tools for studies of elemental and compound actinides. Large changes in the relative atomic cross sections of the 5f, 6d and sp electrons allow decomposition of the character of the valence bands using photoemission. Resonant enhancement of photoelectrons and Auger electrons at the 5d core threshold further aids the decomposition and gives a measure of elemental specificity. Angle-resolved photoemission can be used to map the momentum dependence of the electronic states. The large changes in relative cross section with photon energy yields further details when the mapping is done at equivalent points in multiple zones. Spectra for well understood rare earth materials will be presented to establish spectral characteristics for known atomic character initial states. These signatures will be applied to the case of USb to investigate f-d hybridization near the Fermi level.