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A laser probe <sup>40</sup>Ar /<sup>39</sup>Ar and INAA investigation of four Apollo granulitic breccias
Infrared laser probe 40Ar/39Ar geochronology, instrumental neutron activation analysis (INAA) and analytical electron microscopy have been performed on four 0.5 x 1.0 x 0.3 cm polished rock tiles of Apollo 16 and 17 granulitic breccias (60035, 77017, 78155, and 79215). Pyroxene thermometry indicates that these samples were re-equilibrated and underwent peak metamorphic sub-solidus recrystallization at
1000 – 1100°C, which resulted in homogeneous mineral compositions and granoblastic textures.
40Ar/39Ar data from this study reveal that three samples (60035, 77017, and 78155) have peak metamorphic ages of ~4.1 Ga. Sample 79215 has a peak metamorphic age of 3.9 Ga, which may be related to Serenitatis basin formation. All four samples contain moderately high concentrations of meteoritic siderophiles. Enhanced siderophile contents in three of the samples provide evidence for projectile
contamination of their target lithologies occurring prior to peak metamorphism.
Post-peak metamorphism, low-temperature (<300ºC) events caused the partial resetting of argon in the two finer-grained granulites (60035 and 77017). These later events did not alter the mineralogy or texture of the rocks, but caused minor brecciation and the partial release of argon from plagioclase. Interpretation of the low-temperature data indicates partial resetting of the argon systematics to as young as 3.2 Ga for 60035 and 2.3 Ga for 77017. Cosmic ray exposure ages range from 6.4 to ~339 Ma.
Our results increase the amount of high-precision data available for the granulitic breccias and lunar highlands crustal samples. The results demonstrate the survival of pre-Nectarian material on the lunar surface and document the effects of contact metamorphic and impact processes during the pre-Nectarian Epoch, as well as the low-temperature partial resetting of ages by smaller impact events after 3.9 Ga.
The mineralogy and chemical composition of these rocks, as well as exhumation constraints, indicate that the source of heat for metamorphism was within kilometres of the surface via burial beneath impact melt sheets or hot ejecta blankets
Inner speech and clarity of self-concept in thought disorder and auditory-verbal hallucinations
Eighty patients and thirty controls were interviewed using one interview that promoted personal disclosure and another about everyday topics. Speech was scored using the Thought, Language and Communication scale (TLC). All participants completed the Self-Concept Clarity Scale (SCCS) and the Varieties of Inner Speech Questionnaire (VISQ). Patients scored lower than comparisons on the SCCS. Low scores were associated the disorganized dimension of TD. Patients also scored significantly higher on condensed and other people in inner speech, but not on dialogical or evaluative inner speech. The poverty of speech dimension of TD was associated with less dialogical inner speech, other people in inner speech, and less evaluative inner speech. Hallucinations were significantly associated with more other people in inner speech and evaluative inner speech. Clarity of self-concept and qualities of inner speech are differentially associated with dimensions of TD. The findings also support inner speech models of hallucinations
Ecosystem services bundles:challenges and opportunities for implementation and further research
Background : the concept of ‘ecosystem services bundles’, i.e. ecosystem services that repeatedly appear together across space and/or time, has been developed and refined as part of an integrated approach to assess interactions between ecosystem services. Nevertheless, published evidence of actual use of bundles in decision-making is lacking. In the light of this gap, a review of what bundle approaches have shown and what they can bring to decision-making is timely. Method : we conducted two separate systematic reviews. The first one addressed emerging issues within what we identify as the diverse utilisation and definition of the concept of ‘bundle’ in the literature. The second one focused on papers dealing with bundles as sets of consistently associated services. Review Synthesis : the review first highlights that the confusion surrounding the term ‘bundle’ in ecosystem services literature threatens to weaken the potential for analysis of bundles to inform decision-making. Then, thanks to the review of peer-reviewed papers that detect bundles as sets of consistently associated services, we analyse the diversity of methodological choices and we detail the interactions observed between different ecosystem services across the literature. We also show that landscape features, socio-economic conditions and institutional factors are all potential drivers for the occurrence of specific bundles in a landscape. Discussion : overall, it appears that the analysis of bundles provides an opportunity to enhance policy effectiveness. Nevertheless, the methodological challenges linked to the identification and interpretation of bundles call for careful and reflective study designs. We anticipate that this review will lead to a better understanding by scientists and practitioners of the potential for bundle studies to inform decision-making
Implicit beliefs of disability and elite sport: the para-athlete experience
The purpose of this study was to explore the implicit beliefs and underlying motivational processes of para-athletes, and how these beliefs influenced perceptions of sport performance, as well as challenge the dominant social stereotypes that misconstrue disability as inability. Utilising a qualitative research design, semi-structured interviews were conducted with five elite para-athletes from various sporting backgrounds and analysed from a psychosocial perspective according to the procedures of theoretical thematic analysis. To invoke greater emotional tone and depth, participant-created visual data were used to supplement the initial thematic analysis. Three themes associated with the implicit beliefs of para-athletes were identified and termed, (1) on being disabled, (2) achieving is believing and (3) accepting differences or being indifferent. These themes illustrated how participants had to accept the ‘fixed’ nature of their disability first, before they could work towards overcoming its limitations. Through continuously adapting and adjusting their strategies to address setbacks as they occurred, the process of accepting limitations and overcoming setbacks led to increased feelings of self-efficacy and competence, which consequently led to the dominant incremental beliefs participants held
North Atlantic evidence for a for a unipolar icehouse climate state at the Eocene-Oligocene Transition
This is the final version. Available from Wiley via the DOI in this record.Earth’s climate transitioned from a warm unglaciated state to a colder glaciated ‘icehouse’
state during the Cenozoic. Extensive ice sheets were first sustained on Antarctica at the
Eocene-Oligocene Transition (EOT, ~34 Ma), but there is intense debate over whether
Northern Hemisphere ice sheets developed simultaneously at this time, or tens of millions
of years later. Here we report on EOT-age sediments that contain detrital sand from
Integrated Ocean Drilling Program (IODP) Sites U1406 and U1411 on the Newfoundland
margin. These sites are ideally located to test competing hypotheses of the extent of Arctic
glaciation, being situated in the North Atlantic’s 'iceberg alley' where icebergs, calved from
both the Greenland Ice Sheet today, and the Laurentide Ice Sheet during the Pleistocene,
are concentrated by the Labrador Current and deposit continentally-derived detritus. Here
we show that detrital sand grains present in these EOT-aged sediments from the
Newfoundland margin, initially interpreted to represent ice rafting, were sourced from the
mid-latitudes of North America. We find that these grains were transported to the western
North Atlantic by fluvial and downslope processes, not icebergs, and were subsequently
reworked and deposited by deep-water contour currents on the Newfoundland margin.
Our findings are inconsistent with the presence of extensive ice sheets on southern and
western Greenland, and the northeastern Canadian Arctic. This contradicts extensive
bipolar glaciation at the EOT. The unipolar icehouse arose because of contrasting
latitudinal continental configurations at the poles, requiring more intense Cenozoic
climatic deterioration to trigger extensive Northern Hemisphere glaciation.Royal Societ
Laboratory Focus on Improving the Culture of Biosafety: Statewide Risk Assessment of Clinical Laboratories That Process Specimens for Microbiologic Analysis
The Wisconsin State Laboratory of Hygiene challenged Wisconsin laboratories to examine their biosafety practices and improve their culture of biosafety. One hundred three clinical and public health laboratories completed a questionnaire-based, microbiology-focused biosafety risk assessment. Greater than 96% of the respondents performed activities related to specimen processing, direct microscopic examination, and rapid nonmolecular testing, while approximately 60% performed culture interpretation. Although they are important to the assessment of risk, data specific to patient occupation, symptoms, and travel history were often unavailable to the laboratory and, therefore, less contributory to a microbiology-focused biosafety risk assessment than information on the specimen source and test requisition. Over 88% of the respondents complied with more than three-quarters of the mitigation control measures listed in the survey. Facility assessment revealed that subsets of laboratories that claim biosafety level 1, 2, or 3 status did not possess all of the biosafety elements considered minimally standard for their respective classifications. Many laboratories reported being able to quickly correct the minor deficiencies identified. Task assessment identified deficiencies that trended higher within the general (not microbiology-specific) laboratory for core activities, such as packaging and shipping, direct microscopic examination, and culture modalities solely involving screens for organism growth. For traditional microbiology departments, opportunities for improvement in the cultivation and management of highly infectious agents, such as acid-fast bacilli and systemic fungi, were revealed. These results derived from a survey of a large cohort of small- and large-scale laboratories suggest the necessity for continued microbiology-based understanding of biosafety practices, vigilance toward biosafety, and enforcement of biosafety practices throughout the laboratory setting
cAMP increases junctional conductance and stimulates phosphorylation of the 27-kDa principal gap junction polypeptide.
Correction of Pulmonary Arteriovenous Malformation Using Image-Based Surgical Planning
The objectives of this study were to develop an image-based surgical planning framework that 1) allows for in-depth analysis of pre-operative hemodynamics by the use of cardiac magnetic resonance and 2) enables surgeons to determine the optimum surgical scenarios before the operation. This framework is tailored for applications in which post-operative hemodynamics are important. In particular, it is exemplified here for a Fontan patient with severe left pulmonary arteriovenous malformations due to abnormal hepatic flow distribution to the lungs. Patients first undergo cardiac magnetic resonance for 3-dimensional anatomy and flow reconstruction. After analysis of the pre-operative flow fields, the 3-dimensional anatomy is imported into an interactive surgical planning interface for the surgeon to virtually perform multiple surgical scenarios. Associated hemodynamics are predicted by the use of a fully validated computational fluid dynamic solver. Finally, efficiency metrics (e.g., pressure decrease and hepatic flow distribution) are weighted against surgical feasibility to determine the optimal surgical option
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