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In lekking systems, females can observe both male courtship displays and fights. It has been theorized that male-male agonism may function as a display, giving females more information about mate quality. However, males in many species, such as Greater Sage-grouse, often fight when females are absent, and can even attack during copulation attempts in seeming conflict with females’ choices.Traditional correlational approaches are inadequate to distinguish the underlying mechanisms of social interaction and can result in misleading associations between fighting and mating events. Using observations from a wild population, we posit a novel Relational Event Model that incorporates temporal dependencies of events among a network of individuals. We investigate how fighting among male sage-grouse predicts events such as future fights, copulation solicitations, and interrupted copulations.Our analysis reveals that fighting’s primary function is not to impress females. Indeed, males are less likely to start and more likely to leave fights with females present, plausibly to avoid entanglement in conflict that reduces availability to mate. Moreover, being drawn into these latter viscous cycles of combat and retribution constitutes a significant risk associated with initiating attacks on other males. However, fighting serves other roles, e.g., to deter copulation interruptions and rebuff competitors. Our findings suggest that social systems that regulate conflict and promote females’ choice based on display are likely fundamental to the stable evolution of leks.

Current state-of-the-art fission product separations frequently involve multiple independent separation columns and sample manipulation processes; to couple these processes together, multiple evaporation and transposition steps are often required. The addition of these steps results in lengthy separation times, increased analysis costs, the potential for sample loss, and release of radioactive contamination. We report a new semiautomated method for the rapid separation of U, Zr, Mo, Ba, Sr, Te, and lanthanide fission products from irradiated uranium samples. Chemical yields for U, Zr, Ba, Sr, Te and the lanthanides from less than 3-day old uranium fission product samples are consistently greater than 90%, while those of Mo are greater than 70%. This method minimizes the use and addition of oxidation and reduction reagents that often cause issues with retention and separation. Uranium dissolution and fission product separations using this single-pass method are achievable in under 2 h, representing a significant improvement over traditional gravimetric uranium fission product separation procedures.

Analytical methods for separating individual lanthanide elements from each other are needed to support various scientific fields. This work reports a systematic evaluation of analytical separations using Eichrom Industries Ln resin and simple peristaltic pump fed low-pressure chromatography columns. Systematic studies of isocratic elutions over a range of acid concentrations (0.10 to 0.25 M HNO3) and column lengths (15 to 45 cm) show that with careful selection of the separation conditions baseline separation of the majority of the lanthanide elements can be achieved, with the exception Nd, Pr, Pm and Ce which co-elute at low acid concentrations. The employment of a novel Ce3+/Ce4+ oxidation–reduction approach using NaBrO3 and ascorbic acid enables isolation of Ce, however baseline separation of Nd, Pr and Pm could not be accomplished using Ln resin, simple acids, and low-pressure chromatography. A method for rapid separation and preconcentration of fission product lanthanides is also reported based upon the optimized conditions identified in this work; the separation approach enables isolation of lanthanide isotopes in high purity and chemical yield, with final elution fraction volumes of 4 mLs

Plant-soil feedbacks (PSFs) mediate plant community dynamics and may plausibly facilitate plant invasions. Microbially mediated PSFs are defined by plant effects on soil microbes and subsequent changes in plant performance (responses), both positive and negative. For microbial interactions to benefit invasive plants disproportionately, native and invasive plants must either (1) have different effects on and responses to soil microbial communities or (2) only respond differently to similar microbial communities. In other words, invasive plants do not need to cultivate different microbial communities than natives if they respond differently to them. However, effects and responses are not often explored separately, making it difficult to determine the underlying causes of performance differences. We performed a reciprocal-transplant PSF experiment with multiple microbial inhibition treatments to determine how native and non-native lineages of Phragmites australis affect and respond to soil bacteria, fungi, and oomycetes. Non-native Phragmites is a large, fast-growing, cosmopolitan invasive plant, whereas the North American native variety is comparatively smaller, slower growing, and typically considered a desirable wetland plant. We identified the effects of each plant lineage on soil microbes using DNA meta-barcoding and linked plant responses to microbial communities. Both Phragmites lineages displayed equally weak, insignificant PSFs. We found evidence of slight differential effects on microbial community composition, but no significant differential plant responses. Soils conditioned by each lineage differed only slightly in bacterial community composition, but not in fungal composition. Additionally, native and non-native Phragmites lineages did not significantly differ in their response to similar soil microbial communities. Neither lineage appreciably differed when plant biomass was compared between those grown in sterile and live soils. Targeted microbial inhibitor treatments revealed both lineages were negatively impacted by soil bacteria, but the negative response was stronger in non-native Phragmites. These observations were opposite of expectations from invasion theory and imply that the success of non-native Phragmites, relative to the native lineage, does not result from its interaction with soil microorganisms. More broadly, quantifying plant effects on, and responses to soil microbes separately provides detailed and nuanced insight into plant-microbial interactions and their role in invasions, which could inform management outcomes for invasive plants.

Sexual conflict over the indirect benefits of mate choice may arise when traits in one sex limit the ability of the other sex to freely choose mates but when these coercive traits are not necessarily directly harmful (i.e. forced fertilization per se). Although we might hypothesize that females can evolve resistance in order to retain the indirect, genetic benefits (reflected in offspring attractiveness) of mating with attractive males, up to now it has been difficult to evaluate potential underlying mechanisms. Traditional theoretical approaches do not usually conceptually distinguish between female preference for male mating display and female resistance to forced fertilization, yet sexual conflict over indirect benefits implies the simultaneous action of all of these traits. Here, we present an integrative theoretical framework that draws together concepts from both sexual selection and sexual conflict traditions, allowing for the simultaneous coevolution of displays and preferences, and of coercion and resistance. We demonstrate that it is possible for resistance to coercion to evolve in the absence of direct costs of mating to preserve the indirect benefits of mate choice. We find that resistance traits that improve the efficacy of female mating preference can evolve as long as females are able to attain some indirect benefits of mating with attractive males, even when both attractive and unattractive males can coerce. These results reveal new evolutionary outcomes that were not predicted by prior theories of indirect benefits or sexual conflict.

A 40-item short form version (ASPA-SF) of the Adult Scale of Parental Attachment (ASPA; Snow et al. 2005) was constructed with a focus on instrument item selection, factor structure, and psychometric properties. The ASPA is a self-report measure that assesses individuals’ perceptions of patterns of relating based on their relationships with both mother and father figures in childhood. An exploratory factor analysis (EFA), involving archived responses from the original work on developing the ASPA, supported the 5 factors of Safe, Dependent, Parentified, Fearful, and Distant in the ASPA-SF. Further verification of the ASPA-SF was established through confirmatory factor analysis (CFA) and validity was determined in relation to the Parental Bonding Instrument (PBI; Parker et al. in British Journal of Medical Psychology, 52, 1–10, 1979) with a separate group of 250 respondents.

Idaho National Laboratory (INL) is a nuclear research facility located in southeastern Idaho, USA; over the course of its operational history, INL has operated 52 reactors and 1 reactor fuel reprocessing facility. To determine the extent to which previous nuclear operations at INL have impacted local environmental carbon-14 (14C) concentrations, tree and soil samples from the INL desert and surrounding areas were collected, combusted, and analyzed by Accelerator Mass Spectrometry (AMS). Transport models of the plumes from the Advanced Test Reactor Facility (ATR) and the Idaho Chemical Processing Plant (ICPP) suggest the historic annual integrated plume distributions from each of these source terms was most likely in the northeast-southwest direction, with very little ground contact from stack emissions in the immediate vicinity of the facilities and maximum estimated ground contact arising ∼400–1000 m to the northeast/southwest from each facility. 14C data from annual growth ring data from trees located immediately adjacent to the ATR, INL’s Central Facilities Area (CFA), and Mud Lake, Idaho (ML) are in statistical agreement with regional nuclear weapons testing fallout backgrounds. Surface soil samples taken near a low level radioactive disposal facility and downwind from the ICPP show percent modern carbon (pMC) values ranging from 28 ± 2 to 92 ± 4, suggesting a mixture of aged and modern background carbon containing materials. Taken together, these data suggest that 14C in the INL region is predominantly derived from a mixture of aged and modern background sources (e.g. nuclear weapons testing fallout), with insignificant contributions from INL source terms.

Scandium-47 (

In August 2005 Hurricane Katrina hit the Louisiana and Mississippi Gulf Coast Regions. Throughout history, mental health professionals have primarily focused on adults as the identified victims of natural disasters. More recently, mental health professionals are focused on integrating mental health services to children and adolescents. This article discusses the impact natural disasters have on children, and the related traumatic stress response and post traumatic stress disorder often experienced by children. Treating children can be complicated and a developmentally appropriate intervention is needed. Evidenced-based research has shown play therapy to be a developmentally effective intervention with traumatised children. This article presents two case studies of play therapy with children affected by Hurricane Katrina.

Journal of Instrumentation 15(09), P09004 (2020). doi:10.1088/1748-0221/15/09/P09004, For the Phase-II Upgrade of the ATLAS Detector [1], its Inner Detector, consisting of silicon pixel, silicon strip and transition radiation sub-detectors, will be replaced with an all new 100% silicon tracker, composed of a pixel tracker at inner radii and a strip tracker at outer radii. The future ATLAS strip tracker will include 11,000 silicon sensor modules in the central region (barrel) and 7,000 modules in the forward region (end-caps), which are foreseen to be constructed over a period of 3.5 years. The construction of each module consists of a series of assembly and quality control steps, which were engineered to be identical for all production sites. In order to develop the tooling and procedures for assembly and testing of these modules, two series of major prototyping programs were conducted: an early program using readout chips designed using a 250 nm fabrication process (ABCN-250) [2,2] and a subsequent program using a follow-up chip set made using 130 nm processing (ABC130 and HCC130 chips). This second generation of readout chips was used for an extensive prototyping program that produced around 100 barrel-type modules and contributed significantly to the development of the final module layout. This paper gives an overview of the components used in ABC130 barrel modules, their assembly procedure and findings resulting from their tests., Published by Inst. of Physics, London

Scandium-47 (47Sc) is of high value for targeted radiotherapy and theranostics; we report a novel, cost-effective approach to produce high-purity 47Sc via photonuclear reactions with natural vanadium. Irradiation at 20 MeV photon end-point energy produces >99.998% pure 47Sc, while irradiation at 38 MeV produces 98.8 ± 1.6% pure 47Sc. Experimental data suggest producing greater than 100 mCi (3700 MBq) of 47Sc using this approach may be feasible. Future research into refinement and scale-up to support pre-clinical research is recommended.

Study Objective To evaluate for a dose-response relationship in the association between progestins used for non-contraceptive indications (e.g., endometriosis) and venous thromboembolism (VTE). Design Nested case-control study. Setting The IBM® MarketScan® Databases include routinely collected inpatient, outpatient, and pharmacy claims data among privately insured individuals in the US. Patients or Participants Records of 45 million women aged 15-49 years old were evaluated from 2009-2018. Cases with VTE (n=21,405) were identified by validated ICD-9/10 codes and excluded for recent pregnancy, recent estrogen prescription, or indications for ultra-high dose progestins (e.g., endometrial intraepithelial neoplasia). Controls (n=107,025) were individually age-matched 5:1 by risk set sampling. Interventions N/A. Measurements and Main Results Oral progestin exposures and covariates were defined by prescription claims and ICD-9/10 codes, respectively, within 1 year before the index date. Multivariate conditional logistic regression models determined odds ratios with 95% confidence intervals adjusted for VTE risk factors. The dose-response relationship was assessed by two separate exploratory analyses. The first analysis compared new and chronic use with non-use. The second analysis evaluated progestin exposure as a weighted average daily dose. Significance was set at p Conclusion Non-contraceptive progestins are associated with increased VTE risk. This study provides the first assessment and support of the dose-response relationship. Clinicians should consider using the lowest effective dose to balance risks and benefits.

This work describes a radiochemical separation procedure for the determination of gold (Au), platinum (Pt), tantalum (Ta), and tungsten (W) activation in the presence of fission products. Chemical separations result in a reduction in the minimum detectable activity by a factor of 287, 207, 141, and 471 for 182Ta, 187W, 197Pt, and 198Au respectively, with greater than 90% recovery for all elements. These results represent the highest recoveries and lowest minimum detectable activities for 182Ta, 187W, 197Pt, and 198Au from mixed fission-activation product samples to date, enabling considerable refinement in the measurement uncertainties for neutron fluences in highly complex sample matrices.

We provide the first description of nest architecture and composition, adult construction behavior, and egg characteristics for the genus Rhytipterna. We provide these data for a nest of the Rufous Mourner (Rhytipterna h. holerythra) found under construction and followed through clutch completion and subsequent failure at La Selva Biological Station, Heredia, Costa Rica. Given the historically labile taxonomic placement of the genus Rhytipterna, our observations provide important additional lines of evidence further supporting its affinity to Myiarchus within the Tyrannidae. We highlight our record of the incorporation of shed reptile skins in the nest lining, only the second instance of this nest character within Tyrannidae outside of the genus Myiarchus. The phylogenetic distribution of this specialized nesting trait suggests the possibility of a single origin near the base of the subclade Tyranninae. Received 29 August 2016. Accepted 30 November 2016.

Tantalum (Ta), hafnium (Hf), and tungsten (W) analyses from complex matrices require high purification of these analytes from each other and major/trace matrix constituents, however, current state-of-the-art Ta/Hf/W separations rely on traditional anion exchange approaches that show relatively similar distribution coefficient (Kd) values for each element. This work reports an assessment of three commercially available extraction chromatographic resins (TEVA, TRU, and UTEVA) for Ta/Hf/W separations. Batch contact studies show differences in Ta/Hf and Ta/W Kd values of up to 10 6 and 10 4 (respectively), representing an improvement of a factor of 100 and 300 in Ta/Hf and Ta/W Kd values (respectively) over AG1 × 4 resin. Variations in the Kd values as a function of HCl concentration for TRU resin show that this resin is well suited for Ta/Hf/W separations, with Ta/Hf, Ta/W, and W/Hf Kd value improvements of 10, 200, and 30 (respectively) over AG1 × 4 resin. Analyses of digested soil samples (NIST 2710a) using TRU resin and tandem TEVA-TRU columns demonstrate the ability to achieve extremely high purification (>99%) of Ta and W from each other and Hf, as well as enabling very high purification of Ta and W from the major and trace elemental constituents present in soils using a single chromatographic step.

Hydrocarbons produced via hydraulic fracturing of shale formations frequently contain elevated quantities of Technologically Enhanced Naturally Occurring Radioactive Materials (TENORM) that are difficult to dispose of and can be harmful to the environment. This research investigates the elemental composition of seven major shale formations at the bulk and microstructural scale to better understand the relationship between major naturally occurring radioactive elements (NORM) and organic phases within shales. Bulk mineralogy analysis was performed via powder X-ray diffraction to identify which shales were ideal for hydraulic stimulation based on the content of ductile and brittle minerals. To complement the XRD, Quantitative Evaluation of Minerals by Scanning Electron Microscopy (QEMSCAN®) was performed to identify non-crystalline phases and provide spatial mapping of the minerals through the shale samples. In addition, XRD and QEMSCAN were used to determine the total sulfur and carbonate content as this greatly contributes to the acidity of the shale and subsequently, U and Th migration. Select samples were characterized by scanning electron microscopy - energy dispersive x-ray spectroscopy (SEM/EDX) to reveal the presence of heavy metals (i.e. U, Pb) near hydrocarbon-rich regions of the shale. The NORM content and organic content were also correlated using gamma well logging.

Study Objective We evaluated the impact of opening a Level I Trauma Center on quality measures in GynES. The primary outcome was the time elapsed between case request and patient arrival to the operating room (R:R time). Design This retrospective cohort study compared cases in 2017 (pre-intervention) to 2019 (post-intervention) in a convenience sample. Setting Urban academic tertiary-care hospital, single institution. Patients or Participants Women were included (n=228) if they presented to the Emergency Department and underwent GynES for one of the three indications: ectopic pregnancy, miscarriage, or adnexal torsion. Interventions The intervention period in 2018 included modernizing the Emergency Department, instituting a surgical priority classification system (R:R time targets: A Measurements and Main Results Two reviewers assigned priority class retrospectively for pre-intervention cases (Kappa=0.60). A third reviewer adjudicated discrepancies. R:R time was assessed by difference of means [95% CI] and percent compliant with targets using Welch's T-Test and Fisher's Exact Test (alpha=0.05), respectively. Interrupted time series logistic regression evaluated for secular trends. When compared to 2017 (n=111), R:R time in 2019 (n=117) was significantly reduced for class A cases (-42min [-67 to -17min], p=0.02) and class B cases (-59min [-99 to -20min], p=0.004). Overall compliance significantly improved from 50% to 71%, p=0.002. Logistic regression did not find confounding from pre-intervention trends. Patient and case characteristics were similar except for insurance mix, p=0.04. Conclusion Implementation of a Level I Trauma Center and surgical priority classification system significantly reduced delays for the most urgent gynecologic emergency surgeries.

Study Objective To assess changes in performance characteristics of the initial diagnoses established during a gynecologic consult for PUL after implementation of overnight formal ultrasound. Design This retrospective cohort study compares pre-intervention (2017) and post-intervention (2019) periods in a convenience sample. Setting Urban academic tertiary-care hospital, single institution. Patients or Participants Reproductive-aged women were included if they underwent a gynecologic consult for symptomatic PUL in the Emergency Department during after-hours (18:00-08:00). A total of 325 of 810 (40%) screened patients met inclusion criteria. For primary outcome analysis, 97 of 147 (66%) patients in 2017 and 111 of 178 (63%) patients in 2019 completed follow-up to final diagnosis. Interventions Overnight formal ultrasound was implemented Monday through Friday night in 2018 and was performed before or during a gynecologic consult. Measurements and Main Results Primary outcomes were gynecologic consult performance characteristics (eg- sensitivity, specificity, and predictive values). Quality measures relevant to early diagnosis of EP were also investigated. Descriptive statistics and significance were calculated using T-Test, Fisher's Exact, or Chi-square where appropriate (alpha=0.05). Fewer patients at the initial consult were discharged with a diagnosis of PUL, from 55% in 2017 to 30% in 2019, p=0.0002. Accurate initial diagnosis of EP increased from 52% to 76% of all EP, p=0.046. Positive predictive value for initial EP diagnosis improved from 79% to 97%, p=0.047. Populations were similar in baseline characteristics, admission for observation, and management of EP. Conclusion Overnight formal ultrasound increased accurate diagnosis of EP at the initial consult. Ongoing quality assessment should be considered for emergency gynecologic care.

Distribution coefficient (Kd) data provides the analyst with a powerful set of tools for designing elemental chemical separations. While considerable Kd data exists in the literature for traditional anion and cation exchange resins, a comprehensive Kd study for the majority of the periodic table has not been published to date for several newer Eichrom extraction chromatographic resins. Kd values for the sorption of 41 different of elements on TEVA, TRU, UTEVA, and Diphonix resin were determined in this work. The power of Kd data in designing chemical separations is then demonstrated through development of separation methods for several challenging chemical separations including U/Mo/Te, Zr/Nb/Mo, and Cd isolation. Separation methodologies are finally applied to soil samples, where the ability for each separation to perform under complex matrix conditions is evaluated.

Global and regional releases of 14C have resulted from nuclear weapons testing activities; assessment of the chemical behavior and mechanisms of environmental transport and deposition of this radionuclide can assist remediation strategy development efforts and provide insights into global carbon cycling processes. This work reports a systematic evaluation of 14C in surface soils taken from the Nevada National Security Site. Surface soil samples are derived from above- and underground test locations, with underground test sites representing a range from near complete containment to uncontrolled radioactive releases. Only one surface soil taken from a underground test location (i.e. the Baneberry shot) shows elevated 14C concentrations (319 ± 9 pMC) in addition to elevated concentrations of 137Cs, 60Co and 152Eu above regional backgrounds. Surface soils from above-ground test locations show extremely high 14C content (~1000 to 10,000 pMC); elevated concentrations of 152Eu and 60Co for these soils are also observed, with 137Cs at or below background levels. Taken together, these data suggest that 14C in surface soils from above-ground tests is primarily derived from in-situ neutron activation of the native soil material, whereas 14C in surface soils from underground tests may be from either recondensed particulate material or soil activation.

With a half-life of 3.85(5) d, the fission product $^{127}\mathrm{Sb}$ is potentially useful for the characterization of fallout debris that would be collected for forensic analysis following a hypothetical nuclear event. The $\ensuremath{\beta}$ decay of $^{127}\mathrm{Sb}$ has many characteristic $\ensuremath{\gamma}$-ray lines, however, the majority of decay strength is concentrated in the three strongest lines near 686, 473, and 784 keV, based on low-precision spectroscopic measurements from decades ago. In a new measurement of $^{127}\mathrm{Sb}\phantom{\rule{4pt}{0ex}}\ensuremath{\beta}$ decay, obtained from radiochemical separations of U photofission products, we show that the energies of the 686 and 784 lines are actually shifted lower by 0.8 and 1.1 keV, respectively. Such large discrepancies in the nuclear data inhibit accurate isotopic analyses and have important implications, for example, on the assessment of fission debris that might be collected in the days following a nuclear event. Therefore, a new evaluation of $^{127}\mathrm{Sb}\phantom{\rule{4pt}{0ex}}\ensuremath{\beta}$ decay and appropriate revisions to the various nuclear databases are warranted. This paper reports a new set of $\ensuremath{\gamma}$-ray energies and relative intensities corresponding to $^{127}\mathrm{Sb}$ decay.

International audience; AbstractA radiochemical method for producing 82Se sources with an ultra-low level of contamination of natural radionuclides (40K, decay products of 232Th and 238U) has been developed based on cation-exchange chromatographic purification with reverse removal of impurities. It includes chromatographic separation (purification), reduction, conditioning (which includes decantation, centrifugation, washing, grinding, and drying), and 82Se foil production. The conditioning stage, during which highly dispersed elemental selenium is obtained by the reduction of purified selenious acid (H2SeO3) with sulfur dioxide (SO2) represents the crucial step in the preparation of radiopure 82Se samples. The natural selenium (600 g) was first produced in this procedure in order to refine the method. The technique developed was then used to produce 2.5 kg of radiopure enriched selenium (82Se). The produced 82Se samples were wrapped in polyethylene (12 μm thick) and radionuclides present in the sample were analyzed with the BiPo-3 detector. The radiopurity of the plastic materials (chromatographic column material and polypropylene chemical vessels), which were used at all stages, was determined by instrumental neutron activation analysis. The radiopurity of the 82Se foils was checked by measurements with the BiPo-3 spectrometer, which confirmed the high purity of the final product. The measured contamination level for 208Tl was 8–54 μBq/kg, and for 214Bi the detection limit of 600 μBq/kg has been reached.

Determination of environmental tungsten (W) is inhibited by a lack of reference materials and practical methods to remove isobaric and radiometric interferences. We present a method that evaluates the potential use of commercially available sediment, Basalt Columbia River-2 (BCR-2), as a quality control standard for W. Tungsten concentrations determined using neutron activation analysis (NAA) and mass spectrometry are in statistical agreement at the significance level α = 0.05 (92 ± 4 ng g−1 for NAA and 100 ± 7 ng g−1 for mass spectrometry). These results indicate that BCR-2 may be suitable as a quality control standard for future studies.

Source term attribution of environmental contamination following the Fukushima Daiichi Nuclear Power Plant (FDNPP) disaster is complicated by a large number of possible similar emission source terms (e.g. FDNPP reactor cores 1–3 and spent fuel ponds 1–4). Cesium isotopic analyses can be utilized to discriminate between environmental contamination from different FDNPP source terms and, if samples are sufficiently temporally resolved, potentially provide insights into the extent of reactor core damage at a given time. Rice, soil, mushroom, and soybean samples taken 100–250 km from the FDNPP site were dissolved using microwave digestion. Radiocesium was extracted and purified using two sequential ammonium molybdophosphate-polyacrylonitrile columns, following which 135Cs/137Cs isotope ratios were measured using thermal ionization mass spectrometry (TIMS). Results were compared with data reported previously from locations to the northwest of FDNPP and 30 km to the south of FDNPP. 135Cs/137Cs isotope ratios from samples 100–250 km to the southwest of the FDNPP site show a consistent value of 0.376 ± 0.008. 135Cs/137Cs versus 134Cs/137Cs correlation plots suggest that radiocesium to the southwest is derived from a mixture of FDNPP reactor cores 1, 2, and 3. Conclusions from the cesium isotopic data are in agreement with those derived independently based upon themore » event chronology combined with meteorological conditions at the time of the disaster. In conclusion, cesium isotopic analyses provide a powerful tool for source term discrimination of environmental radiocesium contamination at the FDNPP site. For higher precision source term attribution and forensic determination of the FDNPP core conditions based upon cesium, analyses of a larger number of samples from locations to the north and south of the FDNPP site (particularly time-resolved air filter samples) are needed. Published in 2016. This article is a U.S. Government work and is in the public domain in the USA.« less

(135)Cs/(137)Cs isotopic analyses represent an important tool for studying the fate and transport of radiocesium in the environment; in this work the (135)Cs/(137)Cs isotopic composition in environmental samples taken from across Europe is reported. Surface soil and vegetation samples from western Russia, Ukraine, Austria, and Hungary show consistent aged thermal fission product (135)Cs/(137)Cs isotope ratios of 0.58 ± 0.01 (age corrected to 1/1/15), with the exception of one sample of soil-moss from Hungary which shows an elevated (135)Cs/(137)Cs ratio of 1.78 ± 0.12. With the exception of the outlier sample from Hungary, surface soil/vegetation data are in quantitative agreement with values previously reported for soils within the Chernobyl exclusion zone, suggesting that radiocesium at these locations is primarily composed of homogenous airborne deposition from Chernobyl. Seawater samples taken from the Irish Sea show (135)Cs/(137)Cs isotope ratios of 1.22 ± 0.11 (age corrected to 1/1/15), suggesting aged thermal fission product Cs discharged from Sellafield. The differences in (135)Cs/(137)Cs isotope ratios between Sellafield, Chernobyl, and global nuclear weapons testing fallout indicate that (135)Cs/(137)Cs isotope ratios can be utilized to discriminate between and track radiocesium transport from different nuclear production source terms, including major emission sources in Europe.

The integration of graphene and 2D materials into device technologies requires a detailed understanding of how intrinsic and extrinsic forces impact their properties, as well as the development of engineering strategies to vary their properties for a specific response. In this paper we describe and review our efforts for hybridizing graphene in different ways so as to modify or enhance a range of properties. This hybridization comes in the form of chemical or electronic modification for use in applications ranging from chem/bio sensors to nanoelectronics. We discuss results on exploiting chemistry and defects in graphene for chemical vapor sensing, on hybridizing graphene with fluorine atoms for potential use in nanoelectronics, and on electronically hybridizing graphene in multilayer stacks that give rise to new optical and surface properties.

Aeolian and pluvial processes represent important mechanisms for the movement of actinides and fission products at the Earth's surface. Soil samples taken in the early 1970's near a Department of Energy radioactive waste disposal site (the Subsurface Disposal Area, SDA, located in southeastern Idaho) provide a case study for studying the mechanisms and characteristics of environmental actinide and (137)Cs transport in an arid environment. Multi-component mixing models suggest actinide contamination within 2.5 km of the SDA can be described by mixing between 2 distinct SDA end members and regional nuclear weapons fallout. The absence of chemical fractionation between (241)Am and (239+240)Pu with depth for samples beyond the northeastern corner and lack of (241)Am in-growth over time (due to (241)Pu decay) suggest mechanical transport and mixing of discrete contaminated particles under arid conditions. Occasional samples northeast of the SDA (the direction of the prevailing winds) contain anomalously high concentrations of Pu with (240)Pu/(239)Pu isotopic ratios statistically identical to those in the northeastern corner. Taken together, these data suggest flooding resulted in mechanical transport of contaminated particles into the area between the SDA and a flood containment dike in the northeastern corner, following which subsequent contamination spreading in the northeastern direction resulted from wind transport of discrete particles.

The research based on attachment has shown that patterns of relating with primary caregivers in childhood and adolescence influence a person into adulthood, especially with regard to interpersonal relationships, including sexual intimacy. This study utilized a measure of adult parental attachment style to determine whether the perception of one’s patterns of relating with parental figures in childhood and one’s sexual attitudes are associated with unwanted sexual experiences, ranging from consensual unwanted sex and verbal coercion to more severe forms of coercion, including substance-related and physical coercion. The sample included 488 male and female college students, primarily in the age range of emerging adulthood. Analysis involved canonical correlation, which showed that individuals with avoidant parental attachment styles reported more occurrences of unwanted sex, with gender differences moderating the types of unwanted sex experienced. Of the sexual attitudes, permissiveness emerged as the strongest indicator of unwanted sexual experiences, at times interacting with avoidant attachment. Gender was a moderating variable. The authors conclude with practical implications and suggestions for future research.

135Cs/137Cs isotope ratios can provide the age, origin and history of environmental Cs contamination. Relatively high precision 135Cs/137Cs isotope ratio measurements from samples containing femtogram quantities of 137Cs are needed to accurately track contamination resuspension and redistribution following environmental 137Cs releases; however, mass spectrometric analyses of environmental samples are limited by the large quantities of ionization inhibitors and isobaric interferences which are present at relatively high concentrations in the environment. We report a new approach for Cs purification from environmental samples. An initial ammonium molybdophosphate-polyacrylonitrile (AMP-PAN) column provides a robust, selective method for extracting Cs under a wide variety of sample matrices and mass loads. Application of a novel cation exchange separation approach using AMP-PAN results in more than two orders of magnitude greater Cs/Rb separation factors than commercially available strong cation exchangers. Final sample purification using a microcation column (AG50W resin) enables consistent 2–4% (2σ) measurement errors for samples containing 3–6000 fg 137Cs, representing the highest precision 135Cs/137Cs ratio measurements currently reported for soil samples at the femtogram level.

We describe an aggressive interaction between the extremely rare Jocotoco Antpitta (Grallaria ridgelyi) and a close relative, the Chestnut-naped Antpitta (Grallaria nuchalis). Since first discovered in 1997, ecological information about the Jocotoco Antpitta has begun to accrue; however, much remains to be learned about this rare species in its limited native range. The observations described here advance our knowledge of the behavioral ecology of this elusive species and contribute more broadly to our knowledge of interspecific competition in antpittas in general. We show that in avian systems in which playback experiments fail to detect competition, competition may still be prevalent, in this case manifesting in a nonvocal, physically aggressive interaction. We also raise new questions about the potential for temporal variation in interspecific competition in grallariids due to increased resource demands during nestling provisioning.

Although robust chemical vapor detection by chemielectric point sensors remains as a largely unmet challenge at present, the best performance to date and the most likely avenue for future progress is with sensor designs in which the transductive element is a disordered nanostructured material. We here review the evidence for this claim, with illustrations drawn from recent work on sensors made from gold nanoparticles, carbon nanotubes, and reduced graphene oxide nanoplatelets. These examples can be regarded as being prototypical of disordered nanostructured films formed of primitive objects that are nanoscopic in 3-D, 2-D, and 1-D, respectively.

We evaluated the effect of different forms of singing on cardiorespiratory physiology, and we aimed at disentangling the role of breathing from that of vocal production. Cardiorespiratory recordings were obtained from 20 healthy adults at rest and during: a) singing of familiar slow songs as in the standard form of Western culture; b) improvised vocalization of free vowel sounds, known as toning. To disentangle the role of breathing from that of vocal production, we compared the vocal conditions with matched breathing-only conditions. Toning significantly improved heart rate variability, ventilatory efficiency and slowed respiration to almost exactly six breaths per minute (p