Spacecraft sample collection and subsurface excavation of asteroid (101955) Bennu.

Carbonaceous asteroids, such as (101955) Bennu, preserve material from the early Solar System, including volatile compounds and organic molecules. We report spacecraft imaging and spectral data collected during and after retrieval of a sample from Bennu's surface. The sampling event mobilized rocks and dust into a debris plume, excavating a 9-meter-long elliptical crater. This exposed material is darker, spectrally redder, and more abundant in fine particulates than the original surface. The bulk density of the displaced subsurface material was 500 to 700 kilograms per cubic meter, which is about half that of the whole asteroid. Particulates that landed on instrument optics spectrally resemble aqueously altered carbonaceous meteorites. The spacecraft stored 250 ± 101 grams of material, which will be delivered to Earth in 2023.

Decoding crystallography from high-resolution electron imaging and diffraction datasets with deep learning.

While machine learning has been making enormous strides in many technical areas, it is still massively underused in transmission electron microscopy. To address this, a convolutional neural network model was developed for reliable classification of crystal structures from small numbers of electron images and diffraction patterns with no preferred orientation. Diffraction data containing 571,340 individual crystals divided among seven families, 32 genera, and 230 space groups were used to train the network. Despite the highly imbalanced dataset, the network narrows down the space groups to the top two with over 70% confidence in the worst case and up to 95% in the common cases. As examples, we benchmarked against alloys to two-dimensional materials to cross-validate our deep-learning model against high-resolution transmission electron images and diffraction patterns. We present this result both as a research tool and deep-learning application for diffraction analysis.

Implementation of focused ion beam (FIB) system in characterization of nuclear fuels and materials.

Beginning in 2007, a program was established at the Idaho National Laboratory to update key capabilities enabling microstructural and micro-chemical characterization of highly irradiated and/or radiologically contaminated nuclear fuels and materials at scales that previously had not been achieved for these types of materials. Such materials typically cannot be contact handled and pose unique hazards to instrument operators, facilities, and associated personnel. Over the ensuing years, techniques have been developed and operational experience gained that has enabled significant advancement in the ability to characterize a variety of fuel types including metallic, ceramic, and coated particle fuels, obtaining insights into in-reactor degradation phenomena not achievable by any other means. The following article describes insights gained, challenges encountered, and provides examples of unique results obtained in adapting dual beam FIB technology to nuclear fuels characterization.

Female-selective abortion in Asia: patterns, policies, and debates.

Since the early 1980s, the use of sex-selective abortion increased in many Asian contexts. Estimates indicate that several million female fetuses were aborted in the last two decades of the twentieth century. This article takes a currently unusual approach for a cultural anthropologist in pursuing cross-national comparisons of trends in sex-selective abortion. The risks involved in such an approach are taken in the hope that it will yield insights not gained through localized analysis. After reviewing the available evidence on female-selective abortion, I discuss features of Asian culture that support strong son preference. Next I review the related issues of increased technological availability for prenatal sex selection and national policies about sex selection. Last, I consider several positions on female-selective abortion and how cultural anthropology may contribute to understanding the global context and consequences of prenatal gender discrimination.

Ovarian tumors in rats induced by chronic 2,3,7,8-tetrachlorodibenzo-p-dioxin treatment.

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is a multispecies reproductive toxicant, and it has been recently classified by IARC as a known human carcinogen. Here, we report that TCDD promotes the development of ovarian tumors in an initiation-promotion model in female Sprague Dawley rats. Rats were initiated with diethylnitrosamine (DEN) or vehicle at 70 days of age. Starting 2 or 18 weeks after initiation, rats were exposed biweekly to TCDD at a daily average dose of 125 ng/kg/day for 14, 30, or 60 weeks continuously or for 30 weeks plus withdrawal periods of 16 or 30 weeks. Fifteen of 76 (20%) rats initiated with DEN and promoted with TCDD for various lengths of time developed ovarian sex cord-stromal tumors of Sertoli cell type, whereas no ovarian tumors developed in 86 rats used as vehicle controls or that received DEN alone or TCDD alone. The highest tumor incidence occurred in 6 of 14 rats (43%) after 60 weeks of continuous TCDD after DEN initiation. One of six rats developed a tumor by 30 weeks of exposure. Because most effects of TCDD can be attributed to its activation of the aryl hydrocarbon receptor (AhR), the presence and localization of AhR was determined in the rat ovary and in the ovarian tumors by reverse transcription-PCR, immunohistochemistry, and in situ hybridization. AhR was localized to oocytes, granulosa and thecal cells of growing follicles, surface epithelial cells, and epithelial cells lining single tubules in ovaries from adult control Sprague Dawley rats. Neoplastic cells in the ovarian tumors were also positive for both AhR message and protein. These results indicate that the ability of TCDD to cause ovarian tumors is dependent on initiation, length of promotion, and age of the animal when exposed and evaluated. The tumor type induced by TCDD in this experimental system is the same histological subtype as that reported from an early study of youngsters exposed during an industrial accident in Seveso, Italy.

Evolving the biobehavioral family model: the fit of attachment.

The 1993 Biobehavioral Family model (BBFM) posits that family relational patterns and biobehavioral reactivity interact so as to influence the physical and psychological health of the children. The revised 1999 BBFM incorporates parent-child attachment as a pivotal construct. The current study tests the 1999 BBFM by predicting, in asthmatic children, that child perception of parental relationship quality, triangulation of child in marital conflict, and parent-child security of relatedness will be associated with hopelessness and vagal activation (one mechanism of airway compromise in asthma). In this study, 22 children with asthma (11 males/11 females, aged 8 to 16), watched, alone, an emotionally challenging movie, then engaged in family discussion tasks (problem solving, loss, conflict, cohesion) and completed the Children's Perception of Interparental Scale, the Relatedness Questionnaire, The Multidimensional Scale of Anxiety in Children, and the Hopelessness Scale for Children. Heart rate variability, measured at baseline and throughout the movie and family tasks, was used to compute respiratory sinus arrhythmia (RSA)--an inferential measure of vagal activation. The child's perception of parental conflict showed trends of association with triangulation and insecure father-child relatedness. Triangulation and hopelessness also were associated with insecure father-child relatedness, all of which were associated with vagal activation. Insecure mother-child relatedness was correlated only with hopelessness. Anxiety was not related to any variables. These findings lend support to the 1999 BBFM, and suggest a key role for parent-child attachment.

The influence of parent-child relatedness on depressive symptoms in children with asthma: tests of moderator and mediator models.

OBJECTIVE: To examine the influence of parent-child relationship quality on the association between illness-related functional status and depressive symptoms in children with asthma. METHODS: Questionnaire data were collected from the child, caregiver, and physician. Fifty-five children with asthma (8-17 years of age), their caregivers, and physicians participated. RESULTS: Regression analyses suggest that patterns of mother-child relatedness (secure vs. insecure) mediate the relationship between functional status and depressive symptoms. CONCLUSIONS: The parent-child relationship may be an important pathway by which illness influences symptoms of depression in children with asthma. This study suggests that impaired functional status does not directly contribute to symptoms of depression, but rather influences the parent-child relationship in ways that may promote the development of depressive symptoms in the child.

Differences in kinetics of induction and reversibility of TCDD-induced changes in cell proliferation and CYP1A1 expression in female Sprague-Dawley rat liver.

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is a potent tumor promoter in two-stage initiation-promotion models and induces cell proliferation and development of enzyme-altered hepatic foci. It is believed that increased cell proliferation is a necessary step in carcinogenesis. Therefore, the analysis of the effect of TCDD on cell proliferation in rat liver may aid in the understanding of the mechanism of hepatocarcinogenesis induced by TCDD. The aim of this study was to investigate the time course and reversibility of cell proliferation in non-initiated and diethylnitrosamine-initiated female rats exposed biweekly to a daily averaged dose of 125 ng TCDD/kg/day for up to 60 weeks. In addition we evaluated the suitability of different dose metrics for the evaluation of TCDD-induced changes in cell proliferation and CYP1A1 enzyme induction. Cell proliferation was measured as the incorporation of 5-bromo-2'-deoxyuridine (BrdU) into hepatocytes undergoing replicative DNA synthesis. Mean BrdU labeling indices in TCDD-treated animals were not increased over controls after 14 weeks exposure, but were increased 8- and 2-fold after 30 and 60 weeks' treatment respectively, despite similar liver levels of TCDD at all these times (23-30 p.p.b.). In comparison, CYP1A1 activity, as measured by ethoxyresorufin deethylase activity, was significantly induced at all times points analyzed. Sixteen weeks following cessation of TCDD treatment, labeling indices were still significantly elevated over controls, but after 30 weeks of withdrawal, labeling indices were no different from controls, indicating that TCDD-induced changes in cell proliferation were reversible. Dosimetric analysis indicated that rat liver tissue burden was suitable for prediction of CYP1A1 expression but not cell proliferation and that the area under the curve was unsuitable for prediction of both TCDD-induced changes in CYP1A1 expression and cell proliferation.

Use of solid phase extraction disks for the GC-MS analysis of acidic and neutral herbicides in drinking water.

An analytical procedure was developed in which thirteen herbicides (10 acidic and 3 neutral compounds) may be extracted from drinking water samples using solid phase extraction disks and subsequently analyzed by gas chromatography-mass spectrometry. Using 8 replicate samples consisting of reagent water fortified with nanogram quantities of each herbicide, the average percent recoveries and method detection limits were determined for each analyte. The method was found to be suitable for the determination of individual herbicides in drinking water at concentrations of approximately 10 ng/L.

Social class, gender and intrahousehold food allocations to children in South Asia.

In the 1980s research on gender-biased food distribution to children within the household in South Asia yielded important findings. Many studies report evidence of substantial discrimination against daughters, but others do not. This paper reviews research of the 1980s with attention to social differentiation in gender bias. My hypothesis is that different results concerning gender bias in intrahousehold allocations are expectable, given variations in gender hierarchy throughout South Asia. Results of the review indicate that seemingly "contradictory" results are often accurate reflections of social status differences within South Asia that create varying female health and nutritional outcomes.

Influence of specific emotional states on autonomic reactivity and pulmonary function in asthmatic children.

OBJECTIVE: Research relating depression/hopelessness to cholinergic activation suggests the hypothesis that sad emotional states evoke patterns of autonomic reactivity that predispose to cholinergically mediated airway constriction in asthma. A corollary hypothesis is that positive (e.g., happy) emotional states evoke opposing effects. The purpose of the current study is to assess whether specific emotional states (sadness and happiness) can be reliably induced, physiologically differentiated, and related to asthma-relevant physiologic (autonomic) reactivity and pulmonary function in asthmatic children. METHOD: Twenty-four children, aged 8 to 17 years, with moderate to severe asthma, viewed the movie E.T., The Extra-Terrestrial while having their heart and respiration rate and oxygen saturation continuously recorded. Specific scenes were identified and preselected to evoke sadness, happiness, and a mixture of happiness and sadness. Self-report of emotion and indices of physiologic response were analyzed for these targeted scenes. RESULTS: Sadness was associated with greater heart rate variability and instability of oxygen saturation compared with happiness, with mixed results for mixed happiness and sadness. CONCLUSION: Results support sadness as evoking patterns of autonomic influence consistent with cholinergically mediated airway constriction. Happiness appears to effect autonomic patterns that would tend to relieve airway constriction.

Predominance of dense low-density lipoprotein particles predicts angiographic benefit of therapy in the Stanford Coronary Risk Intervention Project.

BACKGROUND: LDL particles differ in size and density. Individuals with LDL profiles that peak in relatively small, dense particles have been reported to be at increased risk of coronary artery disease. We hypothesized that response to coronary disease therapy in such individuals might differ from response in individuals whose profiles peak in larger, more buoyant LDL. We examined this hypothesis in the Stanford Coronary Risk Intervention Project, an angiographic trial that compared multifactorial risk-reduction intervention with the usual care of physicians. METHODS AND RESULTS: For 213 men, a bimodal frequency distribution of peak LDL density (g/mL) determined by analytical ultracentrifugation was used to classify baseline LDL profiles as "buoyant mode" (density < or = 1.0378) or "dense mode" (density > 1.0378). Coronary disease progression after 4 years was assessed by rates of change (mm/y, negative when arteries narrow) of minimum artery diameter. Rates for buoyant-mode subjects were -0.038 +/- 0.007 (mean +/- SEM) in usual care (n = 65) and -0.039 +/- 0.010 in intervention (n = 56; P = .6). Rates for dense-mode subjects were -0.054 +/- 0.012 in usual care (n = 51) and -0.008 +/- 0.009 in intervention (n = 41, P = .007). Lipid changes did not account for this difference in angiographic response. CONCLUSIONS: Different types of LDL profile may predict different-responses to specific therapies, perhaps because metabolic processes determine both LDL profiles and responses to therapies.

Increased oxidative DNA damage in livers of 2,3,7,8-tetrachlorodibenzo-p-dioxin treated intact but not ovariectomized rats.

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is a more potent hepatocarcinogen in female than in male or ovariectomized rats. A possible mechanism for this increased sensitivity is through enhanced metabolic activation of estrogens by TCDD-induced enzymes leading to oxidative damage in the cell. As a marker for oxidative DNA damage, 8-oxo-deoxyguanosine (8-oxo-dG) was quantitated in livers of intact and ovariectomized Sprague-Dawley rats chronically treated with TCDD (125 ng/kg per day) with and without diethylnitrosamine as initiator. Elevated levels of 8-oxo-dG were detected in a significantly greater number of the intact compared to ovariectomized TCDD-treated rats. Expression of CYP1B1 mRNA, a newly identified cytochrome P450 with proposed estrogen hydroxylase activity, was highly induced by TCDD. The results are consistent with the hypothesis that increased metabolism of endogenous estrogens to catechols by TCDD-induced enzymes may lead to increased oxidative DNA damage and hence contribute to TCDD-mediated hepatocarcinogenicity in female rats.

Toward a more comprehensive medical anthropology: the case of adolescent psychopathology.

This article argues for a more comprehensive analytical approach in medical anthropology than is currently followed, one that combines attention to structural factors (political, economic, medical/psychiatric), experiential/symbolic expressions and meanings, and biological/bodily features of disorders. We show how subject matter that may be defined as "adolescent psychopathology" would be better understood by a comprehensive approach than by partial views. Three areas within adolescent psychopathology are chosen as illustrative: anorexia nervosa, dissociation, and social aggression. Each of these, like adolescence itself, is powerfully shaped by historical and contemporary cultural influences, and each implicates important theories in medical anthropology.

Steady-state nutrition of Pinus resinosa seedlings: response to nutrient loading, irrigation and hardening regimes.

To test effects of fertilization on late-season growth and nutrient content of container-grown red pine (Pinus resinosa Ait.), seedlings were subjected to a factorial combination of two fertilization regimes (exponentially increasing concentrations providing 25 (1N) and 75 (3N) mg N seedling(-1), respectively) and two irrigation regimes (well-watered and water-stressed) followed by drought-hardening or nonhardening. The fertilization treatments gave rise to steady-state nutrition in the seedlings during the prehardening phase. The 3N treatment increased macronutrient uptake significantly more than dry matter production, particularly in the roots, giving rise to what has been called luxury consumption of nutrients, or nutrient loading. Nutrient loading was higher in well-watered seedlings than in water-stressed seedlings. Among well-watered seedlings, relative growth rate of nutrient-loaded seedlings was more sensitive to drought during the hardening phase than that of nonloaded seedlings. However, when watering was resumed at the end of the hardening treatment, the relative growth rate of the nutrient-loaded seedlings (421%) exceeded that of the nonloaded seedlings (213%). Nitrogen accumulation was also higher in nutrient-loaded seedlings than in nonloaded seedlings during the post-hardening phase.

Psychophysiologic reactivity in asthmatic children: a cholinergically mediated confluence of pathways.

OBJECTIVE: The purpose of this study was to determine the suitability of a newly developed experimental paradigm, designed to assess relationships among emotional responsivity, physiologic (autonomic) reactivity, airway reactivity, and pulmonary function in asthmatic children under controlled conditions of ecologically valid emotional stimulation. METHOD: Twenty-four children, aged 8 through 17, with moderate to severe asthma viewed the movie, E.T., the Extra-Terrestrial, while having their heart and respiration rate and oxygen saturation continuously measured and recorded. Airway reactivity was assessed by the methacholine challenge test, and pre- and postmovie pulmonary function by spirometry. Self-report of emotion was recorded for targeted scenes. RESULTS: Findings indicated that emotional responsivity and physiologic reactivity to the movie were associated with increased airway reactivity and with decreased pulmonary function. CONCLUSIONS: The pattern of results suggests cholinergically mediated psychophysiologic pathways of emotional influence in the asthmatic process for some asthmatic children. A heuristic biopsychosocial model of these pathways is presented.

On poverty, child survival and gender: models and misperceptions.

PIP: Cross-cultural data on the association between economic development and child survival, especially gender-specific child survival, fail to provide universal support for two widely held assumption: poverty is the primary cause of excess infant and child mortality, and poverty reduction will reduce disparities between male and female infant and child survival. United Nations data for 1993 indicate infant mortality rates of 14/1000 in industrialized countries, 71/1000 for developing countries, and 114/1000 for the least developed countries. However, when the analysis is conducted on a nation-by-nation or regional level, striking non-fits between the development level and infant mortality rate emerge. For example, within the low human development countries category, the infant mortality rate ranges from 28/1000 in the Solomon Islands to 164/1000 in Afghanistan; moreover, in India, the lowest infant mortality rate exists in Kerala, a relatively poor state. These discrepancies reflect the inaccuracy of the assumption that increased economic resources are always used to raise the standard of living of children; additionally reflected is the enhanced child survival in socialist states such as Kerala that prioritize health services over military expenditures. Also inconsistent is evidence that development programs equalize household allocation of food and medial care to male and female children. In many cultures, especially those that require dowries, preferential treatment of sons is a form of poverty avoidance rather that a byproduct of poverty. Social policies that continue to be based on these two widely erroneous assumptions will fail to enhance child survival, especially that of female children.^ieng