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The burden of common perinatal mental disorders (CPMD) in low-and-middle-income countries is substantially higher than high-income countries, with low levels of detection, service provision and treatment in resource-constrained settings. We describe the development of an ultra-short screening tool to detect antenatal depression, anxiety disorders and maternal suicidal ideation.
A sample of 376 women was recruited at a primary-level obstetric clinic. Five depression and anxiety symptom-screening questionnaires, demographics and psychosocial risk questionnaires were administered. All participants were assessed with the Mini-International Neuropsychiatric Interview (MINI), a structured, diagnostic interview. Screening tool items were analysed against diagnostic data using multiple logistic regression and receiver operating curve (ROC) analysis.
The prevalence of MINI-defined major depressive episode (MDE) and/or anxiety disorders was 33%. Overall, 18% of participants expressed suicidal ideation and behaviour, 54% of these had no depression or anxiety diagnosis. Multiple logistic regression identified four screening items that were independently predictive of MDE and anxiety disorders, investigating depressed mood, anhedonia, anxiety symptoms and suicidal ideation. ROC analysis of these combined items yielded an area under the curve of 0.83 (95% CI 0.78–0.88). A cut-off score of 2 or more offered a sensitivity of 78% and specificity of 82%.
This novel screening tool is the first measure of CPMD developed in South Africa to include depressed mood, anxiety symptoms and suicidal ideation. While the tool requires further investigation, it may be useful for the early identification of mental health symptoms and morbidity in the perinatal period.
Background: The NIH Toolbox - Cognition Battery (NIHTB-CB) is a computerized cognitive assessment designed for clinical research that is administered in-person. Here, we explored the feasibility and validity of a novel video-conference protocol for administering the NIHTB-CB. Since our protocol required repeated assessments, we further explored the NIHTB-CB’s practice effect. Methods: Twenty-five healthy participants completed the NIHTB-CB under two separate conditions four weeks apart. The standard condition followed the recommended administration protocol, whereas the video-conference condition had the examiner and participant in separate rooms but able to communicate over video-conference. A linear mixed-model analysis was performed to explore the fixed effect of testing condition and time on NIHTB-CB performance. Results: Across all three NIHTB-CB composite scores (total, fluid and crystallized cognition) no significant fixed effect of administration condition was found. A significant practice effect was observed for the fluid and total cognition composite scores over a 29.0 (± 2.1) day test-retest interval. Conclusions: Our novel video-conference protocol for the NIHTB-CB is equivalent to the standard protocol in healthy participants, and may provide a solution for researchers seeking to engage study participants at remote sites. If the NIHTB-CB is used longitudinally to monitor patients, corrections for repeated measures may be required.
Hand, foot, and mouth disease (HFMD), usually a self-limiting illness for young children, could cause a significant burden for parents because it can take up to 1–2 weeks for a sick child to recover. We conducted a two-wave longitudinal study over one summer peak season (May–July 2014) of HFMD to examine parents’ HFMD-related risk perceptions and protective responses. In total, 618 parents with at least one child aged ⩽12 years, recruited using randomly-dialled household telephone calls completed the baseline survey interview, 452 of whom subsequently completed the follow-up survey. Around two-thirds of participants perceived the chance of their child being infected by HFMD was ‘zero/very small/small’ but the likelihood of being hospitalized once infected was ‘somewhat likely/likely/very likely’. At follow-up, 82% reported washing child's hands frequently (Hygiene), 16% would keep their child away from school if HFMD cases were identified in school (Distancing) and 23% were ‘very likely/certainly’ to take the child for HFMD vaccination if available (Vaccination). Anticipated regret was consistently the strongest predictor for Hygiene (OR 3.34), and intention of Distancing (OR 2.58) and Vaccination (OR 3.16). Interventions focusing on anticipated regret may be effective to promote protective behaviour against HFMD among parents for their children.
Shifting prey distributions due to global warming are expected to generate dramatic ecosystem-wide changes in trophic structure within Arctic marine ecosystems. Yet a relatively poor understanding of contemporary Arctic food webs makes it difficult to predict the consequences of such changes for Arctic predators. Doing so requires quantitative approaches that can track contemporary changes in predator diets through time, using accurate, well-defined methods. Here we use fatty acids (FA) to quantify differences in consumer diet using permutational multivariate analysis of variance tests that characterize spatial and temporal changes in consumer FA signatures. Specifically we explore differences in Greenland shark (Somniosus microcephalus) FA to differentiate their potential trophic role between Svalbard, Norway and Cumberland Sound, Canada. Greenland shark FA signatures revealed significant inter-annual differences, probably driven by varying seal and Greenland halibut responses to environmental conditions such as the NAO, bottom temperature, and annual sea-ice extent. Uncommon FA were also found to play an important role in driving spatial and temporal differences in Greenland shark FA profiles. Our statistical approach should facilitate quantification of changing consumer diets across a range of marine ecosystems.
Why should intellectual historians care about children? Until recently, the answer was that adults’ ideas about children matter, particularly for the history of education and the history of conceptions of the family, but children's ideas are of little significance. Beginning with Philippe Ariès in the 1960s, historians took to exploring how and why adults’ ideas about children changed over time. In these early histories of childhood, young people figured as consumers of culture and objects of socialization, but not as producers or even conduits of ideas.
Secretory immunoglobulin A (IgA) plays a critical role in gut mucosal immune defense. Initially provided by breastmilk, IgA production by the infant gut is gradually stimulated by developing gut microbiota. This study reports associations between infant fecal IgA concentrations 4 months after birth, breastfeeding status and other pre/postnatal exposures in 47 infants in the Canadian Healthy Infant Longitudinal Development cohort. Breastfed infants and first-born infants had higher median fecal IgA concentrations (23.11 v. 9.34 µg/g protein, P<0.01 and 22.19 v. 8.23 µg/g protein, P=0.04). IgA levels increased successively with exclusivity of breastfeeding (β-coefficient, 0.37, P<0.05). This statistical association was independent of maternal parity and household pets. In the absence of breastfeeding, female sex and pet exposure elevated fecal IgA to levels found in breastfed infants. In addition to breastfeeding, infant fecal IgA associations with pre/postnatal exposures may affect gut immunity and risk of allergic disease.
Designing materials for performance in high-radiation fields can be accelerated through a carefully chosen combination of advanced multiscale modeling paired with appropriate experimental validation. The studies reported in this work, the combined efforts of six universities working together as the Consortium on Cladding and Structural Materials, use that approach to focus on improving the scientific basis for the response of ferritic–martensitic steels to irradiation. A combination of modern modeling techniques with controlled experimentation has specifically focused on improving the understanding of radiation-induced segregation, precipitate formation and growth under radiation, the stability of oxide nanoclusters, and the development of dislocation networks under radiation. Experimental studies use both model and commercial alloys, irradiated with both ion beams and neutrons. Transmission electron microscopy and atom probe are combined with both first-principles and rate theory approaches to advance the understanding of ferritic–martensitic steels.
The 2013 multistate outbreaks contributed to the largest annual number of reported US cases of cyclosporiasis since 1997. In this paper we focus on investigations in Texas. We defined an outbreak-associated case as laboratory-confirmed cyclosporiasis in a person with illness onset between 1 June and 31 August 2013, with no history of international travel in the previous 14 days. Epidemiological, environmental, and traceback investigations were conducted. Of the 631 cases reported in the multistate outbreaks, Texas reported the greatest number of cases, 270 (43%). More than 70 clusters were identified in Texas, four of which were further investigated. One restaurant-associated cluster of 25 case-patients was selected for a case-control study. Consumption of cilantro was most strongly associated with illness on meal date-matched analysis (matched odds ratio 19·8, 95% confidence interval 4·0–∞). All case-patients in the other three clusters investigated also ate cilantro. Traceback investigations converged on three suppliers in Puebla, Mexico. Cilantro was the vehicle of infection in the four clusters investigated; the temporal association of these clusters with the large overall increase in cyclosporiasis cases in Texas suggests cilantro was the vehicle of infection for many other cases. However, the paucity of epidemiological and traceback information does not allow for a conclusive determination; moreover, molecular epidemiological tools for cyclosporiasis that could provide more definitive linkage between case clusters are needed.
We investigated a mixed outbreak of Legionnaires' disease (LD) and Pontiac fever (PF) at a military base to identify the outbreak's environmental source as well as known legionellosis risk factors. Base workers with possible legionellosis were interviewed and, if consenting, underwent testing for legionellosis. A retrospective cohort study collected information on occupants of the buildings closest to the outbreak source. We identified 29 confirmed and probable LD and 38 PF cases. All cases were exposed to airborne pathogens from a cooling tower. Occupants of the building closest to the cooling tower were 6·9 [95% confidence interval (CI) 2·2–22·0] and 5·5 (95% CI 2·1–14·5) times more likely to develop LD and PF, respectively, than occupants of the next closest building. Thorough preventive measures and aggressive responses to outbreaks, including searching for PF cases in mixed legionellosis outbreaks, are essential for legionellosis control.
Although it is well known that water is essential for human homeostasis and survival, only recently have we begun to understand its role in the maintenance of brain function. Herein, we integrate emerging evidence regarding the effects of both dehydration and additional acute water consumption on cognition and mood. Current findings in the field suggest that particular cognitive abilities and mood states are positively influenced by water consumption. The impact of dehydration on cognition and mood is particularly relevant for those with poor fluid regulation, such as the elderly and children. We critically review the most recent advances in both behavioural and neuroimaging studies of dehydration and link the findings to the known effects of water on hormonal, neurochemical and vascular functions in an attempt to suggest plausible mechanisms of action. We identify some methodological weaknesses, including inconsistent measurements in cognitive assessment and the lack of objective hydration state measurements as well as gaps in knowledge concerning mediating factors that may influence water intervention effects. Finally, we discuss how future research can best elucidate the role of water in the optimal maintenance of brain health and function.
Crystal plasticity finite element method is a useful tool to investigate the anisotropic mechanical behaviors as well as the microstructure evolution of metallic materials and it is widely used on single crystals and polycrystalline materials. However, grain boundary involved mechanisms are barely included in the polycrystalline models, and modeling the interaction between the dislocation and the grain boundaries in polycrystalline materials in a physically consisstent way is still a long-standing, unsolved problem. In our analysis, a dislocation density based crystal plasticity finite element model is proposed, and the interaction between the dislocation density and the grain boundaries is included in the model kinematically. The model is then applied to Al bicrystals under 10% compression to investigate the effects of grain boundary character, e.g. grain boundary misorientation and grain boundary normal, on the stress state and the microstructure evolution. The modeling results suggest a reasonable correspondence with the experimental result and the grain boundary character plays a crucial role in the stress concentration and dislocation patterning.
This prospective cohort study explored the effects of prenatal and postpartum depression on breastfeeding and the effect of breastfeeding on postpartum depression.
The Edinburgh Postpartum Depression Scale (EPDS) was administered to 145 women at the first, second and third trimester, and at the neonatal period and 3 months postpartum. Self-report exclusive breastfeeding since birth was collected at birth and at 3, 6 and 12 months postpartum. Data analyses were performed using repeated-measures ANOVAs and logistic and multiple linear regressions.
Depression scores at the third trimester, but not at 3 months postpartum, were the best predictors of exclusive breastfeeding duration (β = −0.30, t = −2.08, p < 0.05). A significant decrease in depression scores was seen from childbirth to 3 months postpartum in women who maintained exclusive breastfeeding for ⩾3 months (F1,65 = 3.73, p < 0.10, ηp2 = 0.05).
These findings suggest that screening for depression symptoms during pregnancy can help to identify women at risk for early cessation of exclusive breastfeeding, and that exclusive breastfeeding may help to reduce symptoms of depression from childbirth to 3 months postpartum.
The thiophenes alpha-terthienyl and methyl-alpha-terthienyl are found in many species of the family Asteraceae and are highly phototoxic to mosquito larvae. These compounds and a synthetic analogue, cyano-alpha-terthienyl, controlled Aedes intrudens Dyar (Diptera: Culicidae) larvae at application rates between 10 and 40 g per hectare in field trials. These concentrations are similar to those currently used with chemical control agents. Piperonyl butoxide, a synergist used with pyrethrin, greatly increased the mortality of mosquito larvae at low application rates of the most potent phototoxin, cyano-alpha-terthienyl.Although we have demonstrated previously that these phototoxic defences are effective against some phytophagous insects, more recently we studied insects that are able to feed on a phototoxic plant, in order to examine modes of resistance to phototoxins. Chrysolina spp. (Coleoptera: Chrysomelidae) larvae are susceptible to phototoxicity but avoid it by feeding on Hypericum perforatum L. (Hypericaceae) at dawn and by hiding during the day. Chrysolina adults avoid phototoxicity by the presence of opaque cuticles that block the sunlight. First-instar larvae of Anaitis plagiata (L.) (Lepidoptera: Geometridae) avoid feeding on the glands that contain the phototoxin. Later-instar larvae feed on the entire leaf, yet are not susceptible to phototoxicity, indicating they have biochemical defenses against photo-induced damage.
Trypanosomatids represent the causative agents of major diseases in humans, livestock and plants, with inevitable suffering and economic hardship as a result. They are also evolutionarily highly divergent organisms, and the many unique aspects of trypanosome biology provide opportunities in terms of identification of drug targets, the challenge of exploiting these putative targets and, at the same time, significant scope for exploration of novel and divergent cell biology. We can estimate from genome sequences that the degree of divergence of trypanosomes from animals and fungi is extreme, with perhaps one third to one half of predicted trypanosome proteins having no known function based on homology or recognizable protein domains/architecture. Two highly important aspects of trypanosome biology are the flagellar pocket and the nuclear envelope, where in silico analysis clearly suggests great potential divergence in the proteome. The flagellar pocket is the sole site of endo- and exocytosis in trypanosomes and plays important roles in immune evasion via variant surface glycoprotein (VSG) trafficking and providing a location for sequestration of various invariant receptors. The trypanosome nuclear envelope has been largely unexplored but, by analogy with higher eukaryotes, roles in the regulation of chromatin and most significantly, in controlling VSG gene expression are expected. Here we discuss recent successful proteomics-based approaches towards characterization of the nuclear envelope and the endocytic apparatus, the identification of conserved and novel trypanosomatid-specific features, and the implications of these findings.
The stress—strain behaviour of metallic and polymer thin films are measured using a spherical indenter. A modification of the Hertzian analysis enables the elastic to plastic transition to be analyzed so that the variation of mean pressure versus depth can be calculated. The stress—strain behaviour is then calculated from the mean indentation strain using a relationship proposed by Tabor[l]. Observations of high precision load displacement data generated with a UMIS—2000 instrument are analyzed on the basis of the simple analysis developed. The measured values are compared with simulated data for the same materials.
Composite materials have found a number of structural applications, but their use in the electronics industry has been relatively limited. As the function of electroceramic composites are better understood, we can expect this picture to change. In this paper some of the piezoelectric composite sensor and actuator studies carried out in our laboratory during the past decade will be reviewed. The ideas that provide a basic understanding of functional composites have previously been discussed . This paper describes recent advances in the processing and properties of composites possessing 0-3, 1-3, and 2-2 connectivity made of polymers, metals and ferroelectric ceramics. The introduction of open spaces in the previous connectivity patterns allows the development of new designs of several piezoelectric composites with connectivity patterns of 0(0)-3, 1(0)-3, 2(0)-2-2, and 2-0-2. As in most electronic systems that are developed with improved properties a push toward lower cost and smaller sizes of the piezoelectric ceramics, together with improved reliability and performance occurs. The piezocomposites with open spaces in their structures clearly demonstrate the growth of the functional ceramics into the field of the smart ceramics as the materials for the beginning of the next century.
The surface properties of diamond-like carbon (DLC) films deposited by a vacuum arc technique on smooth silicon wafers are presented with specific emphasis given to stiction reduction in microelectromechanical systems (MEMS). The low deposition temperatures afforded by the vacuum arc technique should allow for easy integration of the DLC films into the current fabrication process of typical surface micromachines by means of a standard lift-off processing technique. Using X-ray photoelectron spectroscopy (XPS), contact angle analysis, and atomic force microscopy (AFM), the surface chemistry, microroughness, hydrophobicity, and adhesion forces of DLC-coated Si(100) surfaces were measured and correlated to the measured water contact angles. DLC films were found to be extremely smooth and possess a water contact angle of 87°, which roughly corresponds to a surface energy of 22 mJ/m2. It is shown that the pull-off forces measured by AFM correlate well with the predicted capillary forces. Pull-off forces are reduced on DLC surfaces by about a factor of five compared to 10 nN pull-off forces measured on the RCA-cleaned silicon surfaces. In the absence of meniscus forces, the overall adhesion force is expected to decrease by over an order of magnitude to the van der Waals attractive force present between two DLC-coated surfaces- To further improve the surface properties of DLC, films were exposed to a fluorine plasma which increased the contact angle to 99° and lowered the pull-off force by approximately 20% over that obtained with as-deposited DLC. The significance of these results is discussed with respect to stiction reduction in micromachines.