Stratigraphy and Whole-Rock Amino Acid Geochronology of Key Holocene and Last Interglacial Carbonate Deposits in the Hawaiian Islands

We evaluated the utility of whole-rock amino acid racemization as a method for the stratigraphic correlation and dating of carbonate sediments in the Hawaiian Islands. D-alloisoleucine/L-isoleucine (A/I) ratios were determined for carbonate sand and sandstone samples from 25 localities in the archipelago. The superposition of A/I ratios within stratigraphic sections and the regional concordance of ratios within geological formations support the integrity of the method. To correlate the A/I ratios with an absolute chronology, comparisons were made with previously published uranium series dates on corals and with 14C dates on carbonate sand and organic material, including several new dates reported herein. The A/I mean from four marine isotope stage (MIS) 5e U-series calibration sites was 0.505 ± 0.027 (n = 11), and 12 "test sites" of previously uncertain or speculative geochronological age yielded an A/I mean of 0.445 ± 0.058 (n = 17). Similarly, extensive Holocene dunes on Moloka'i and Kaua'i were correlated by a mean A/I ratio of 0.266 ± 0.022 (n = 8) and equated with a 14C bulk sediment mean age of 8600 yr B.P. Our results indicate that the eolian dunes currently exposed in various localities in the Islands originated primarily during two major periods of dune formation, the last interglacial (MIS 5e) and the early Holocene (MIS 1). MIS 5e and MIS 1 A/I ratios from the Hawaiian Islands show close agreement with previous whole-rock studies in Bermuda and the Bahamas. We discuss these results in terms of their relevance to models of lithospheric flexure and to imposing constraints on the time frame for the extinction of fossil birds

Determinants of hypertension in West Africa: Contribution of anthropometric and dietary factors to urban-rural and socioeconomic gradients

The determinants of hypertension in West Africa have not been well defined. The authors sampled 598 participants aged 45 years or more from a recent population-based survey in southwest Nigeria (190 rural men and women, 205 urban poor men and women, and 203 retired railway workmen). The estimated mean age was 61 (10) years. Mean pressures were low relative to westernized societies: systolic blood pressure = 124 (24) mmHg, diastolic blood pressure = 72 (13) mmHg. Both men and women were remarkably lean: body mass index = 21.3 (3.6) and 23.0 (5.2) kg/m2, respectively. Hypertension prevalence increased across the gradient from rural farmers to urban poor to railway workers: 14, 25, and 29 percent, respectively, had a blood pressure of 140/90 mmHg or greater, and 3, 11, and 14 percent, respectively, had a blood pressure of 160/95 mmHg or greater (p for trend \u3c 0.01 for both cutpoints). On the basis of a 24-hour urine sample, daily electrolyte excretion was 110 (57) mEq of sodium and 46 (24) mEq of potassium. Mean sodium:potassium ratio was 2.6 (1.0) and was higher among the urban residents (p \u3c 0.01) and correlated with systolic and diastolic pressures (r = 0.16-0,18, p \u3c 0.01). These findings provide quantitative estimates of the impact of known hypertension risk factors in West Africa and demonstrate the basis for increased prevalence with urbanization and associated economic and dietary change. These results also provide support for recommendations for prevention in West Africa and provide a benchmark against which to compare populations in the African diaspora

Taking Inventory of the Creative Behavior Inventory: An Item Response Theory Analysis of the CBI

The original 90-item Creative Behavior Inventory (CBI) was a landmark self-report scale in creativity research, and the 28-item brief form developed nearly 20 years ago continues to be a popular measure of everyday creativity. Relatively little is known, however, about the psychometric properties of this widely used scale. In the current research, we conduct a detailed psychometric investigation into the 28-item CBI by applying methods from item response theory using a sample of 2,082 adults. Our investigation revealed several strengths of the current scale: excellent reliability, suitable dimensionality, appropriate item difficulty, and reasonably good item discrimination. Several areas for improvement were highlighted as well: (1) the four-point response scale should have fewer options; (2) a handful of items showed gender-based differential item functioning, indicating some gender bias; and (3) local dependence statistics revealed clusters of items that are redundant and could be trimmed. These analyses support the continued use of the CBI for assessing engagement in everyday creative behaviors but suggest that the CBI could benefit from thoughtful revision

Structure of the southern Keweenawan rift from COCORP surveys across the Midcontinent Geophysical Anomaly in northeastern Kansas

This is the published version. Copyright 1984 American Geophysical Union. All Rights Reserved.COCORP profiling across the midcontinent geophysical anomaly in northeastern Kansas reveals structural basins and other features of the Precambrian Keweenawan rift buried beneath the Phanerozoic cover. The 40-km-wide main basin is asymmetric, with a maximum depth of 3 km on the east and 8 km on the west. The basin fill is characterized by a lower layered sequence of strong continuous west dipping reflectors which may be correlated with Middle Keweenawan interbedded volcanic and clastic rocks exposed along the MGA in the Lake Superior region. Overlying this layered sequence is a zone of weak, discontinuous reflectors correlated here with the predominantly clastic rocks characteristic of the Upper Keweenawan sequence near Lake Superior. A second tilted but shallower basin lies to the east of the main basin and appears to be filled predominantly with clastic sedimentary rocks. The character of the seismic data, the seismic velocity distribution, and gravity modeling suggest that mafic intrusions lie beneath the main rift basin. Normal faults associated with the rift dip at moderate angles to the east. Palinspastic reconstruction indicates that the rift basin formed by the rotation of fault bounded blocks during crustal extension. Although reactivation of preexisting structures appears to have occurred in many other rifts profiled by COCORP, the evidence is inconclusive on this point in the case of the Kansas data. The structures mapped by COCORP surveys in Kansas and elsewhere suggest that asymmetric sequences of layered reflectors are characteristic, and perhaps diagnostic, of rift basin deposits in general

An Innovative Interactive Modeling Tool to Analyze Scenario-Based Physician Workforce Supply and Demand

Effective physician workforce management requires that the various organizations comprising the House of Medicine be able to assess their current and future workforce supply. This information has direct relevance to funding of graduate medical education. We describe a dynamic modeling tool that examines how individual factors and practice variables can be used to measure and forecast the supply and demand for existing and new physician services. The system we describe, while built to analyze the pathologist workforce, is sufficiently broad and robust for use in any medical specialty. Our design provides a computer-based software model populated with data from surveys and best estimates by specialty experts about current and new activities in the scope of practice. The model describes the steps needed and data required for analysis of supply and demand. Our modeling tool allows educators and policy makers, in addition to physician specialty organizations, to assess how various factors may affect demand (and supply) of current and emerging services. Examples of factors evaluated include types of professional services (3 categories with 16 subcategories), service locations, elements related to the Patient Protection and Affordable Care Act, new technologies, aging population, and changing roles in capitated, value-based, and team-based systems of care. The model also helps identify where physicians in a given specialty will likely need to assume new roles, develop new expertise, and become more efficient in practice to accommodate new value-based payment model

Is Fire a Disturbance in Grasslands?

Many grasslands, and in particular the tallgrass prairies of North America, are generally thought to be maintained by periodic fire. Semantic disagreement among researchers, however, threatens to hamper discussion of fire as an ecological force in grassland ecosystems. Some authors emphasize that fires are disturbances (or perturbations) since these fires disrupt or alter ecosystem states, trends, and dynamics (e.g., accumulating nitrogen is volatilized, plant and animal communities change in composition). Other researchers point out that, because these fire-induced disruptions and alterations can maintain the status quo of the ecosystem (e. g., prevent it from becoming woodland), it is the lack of fire rather than fire itself that should be considered a disturbance. We argue that, since both points of view are useful, there is little to be gained by labeling loosely either fire or the lack thereof as a disturbance in grassland ecosystems

Understanding workflow in telehealth video visits: Observations from the IDEATel project

AbstractHome telemedicine is an emerging healthcare paradigm that has the potential to transform the treatment of chronic illness. The purpose of this paper is to: (1) develop a theoretical and methodological framework for studying workflow in telemediated clinician–patient encounters drawing on a distributed cognition approach and (2) employ the framework in an in-depth analysis of workflow in the IDEATel project, a telemedicine program for older adults with diabetes. The methods employed in this research included (a) videotaped observations of 27 nurse–patient encounters and (b) semi-structured interviews with participants. The analyses were used to provide a descriptive analysis of video visits, understand the mediating role of different technologies and to characterize the ways in which artifacts and representations are used to understand the state of the patient. The study revealed barriers to productive use of telehealth technology as well as adaptations that circumvented such limitations. This research has design implications for: (a) improving the coordination of communication and (b) developing tools that better integrate and display information. Although home telemedicine programs will differ in important respects, there are invariant properties across such systems. Explicating these properties can serve as a needs requirement analysis to develop more effective systems and implementation plans

Clinical actionability of comprehensive genomic profiling for management of rare or refractory cancers

Background. The frequency with which targeted tumor sequencing results will lead to implemented change in care is unclear. Prospective assessment of the feasibility and limitations of using genomic sequencing is critically important. Methods. A prospective clinical study was conducted on 100 patients with diverse-histology, rare, or poor-prognosis cancers to evaluate the clinical actionability of a Clinical Laboratory Improvement Amendments (CLIA)-certified, comprehensive genomic profiling assay (FoundationOne), using formalin-fixed, paraffin-embedded tumors. The primary objectives were to assess utility, feasibility, and limitations of genomic sequencing for genomically guided therapy or other clinical purpose in the setting of a multidisciplinary molecular tumor board. Results. Of the tumors from the 92 patients with sufficient tissue, 88 (96%) had at least one genomic alteration (average 3.6, range 0–10). Commonly altered pathways included p53 (46%), RAS/RAF/MAPK (rat sarcoma; rapidly accelerated fibrosarcoma; mitogen-activated protein kinase) (45%), receptor tyrosine kinases/ligand (44%), PI3K/AKT/mTOR (phosphatidylinositol-4,5-bisphosphate 3-kinase; protein kinase B; mammalian target of rapamycin) (35%), transcription factors/regulators (31%), and cell cycle regulators (30%). Many low frequency but potentially actionable alterations were identified in diverse histologies. Use of comprehensive profiling led to implementable clinical action in 35% of tumors with genomic alterations, including genomically guided therapy, diagnostic modification, and trigger for germline genetic testing. Conclusion. Use of targeted next-generation sequencing in the setting of an institutional molecular tumor board led to implementable clinical action in more than one third of patients with rare and poor-prognosis cancers. Major barriers to implementation of genomically guided therapy were clinical status of the patient and drug access. Early and serial sequencing in the clinical course and expanded access to genomically guided early-phase clinical trials and targeted agents may increase actionability. Implications for Practice: Identification of key factors that facilitate use of genomic tumor testing results and implementation of genomically guided therapy may lead to enhanced benefit for patients with rare or difficult to treat cancers. Clinical use of a targeted next-generation sequencing assay in the setting of an institutional molecular tumor board led to implementable clinical action in over one third of patients with rare and poor prognosis cancers. The major barriers to implementation of genomically guided therapy were clinical status of the patient and drug access both on trial and off label. Approaches to increase actionability include early and serial sequencing in the clinical course and expanded access to genomically guided early phase clinical trials and targeted agents

Universality of the Ising Model on Sphere-like Lattices

We study the 2D Ising model on three different types of lattices that are topologically equivalent to spheres. The geometrical shapes are reminiscent of the surface of a pillow, a 3D cube and a sphere, respectively. Systems of volumes ranging up to O($10^5$) sites are simulated and finite size scaling is analyzed. The partition function zeros and the values of various cumulants at their respective peak positions are determined and they agree with the scaling behavior expected from universality with the Onsager solution on the torus ($\nu=1$). For the pseudocritical values of the coupling we find significant anomalies indicating a shift exponent $\neq 1$ for sphere-like lattice topology.Comment: 24 pages, LaTeX, 8 figure

Calibration and performance of the Galileo solid-state imaging system in Jupiter orbit

The solid-state imaging subsystem (SSI) on the National Aeronautics and Space Administration’s (NASA’s) Galileo Jupiter orbiter spacecraft has successfully completed its 2-yr primary mission exploring the Jovian system. The SSI has remained in remarkably stable calibration during the 8-yr flight, and the quality of the returned images is exceptional. Absolute spectral radiometric calibration has been determined to 4 to 6% across its eight spectral filters. Software and calibration files are available to enable radiometric, geometric, modulation transfer function (MTF), and scattered light image calibration. The charge-coupled device (CCD) detector endured the harsh radiation environment at Jupiter without significant damage and exhibited transient image noise effects at about the expected levels. A lossy integer cosine transform (ICT) data compressor proved essential to achieving the SSI science objectives given the low data transmission rate available from Jupiter due to a communication antenna failure. The ICT compressor does introduce certain artifacts in the images that must be controlled to acceptable levels by judicious choice of compression control parameter settings. The SSI team’s expertise in using the compressor improved throughout the orbital operations phase and, coupled with a strategy using multiple playback passes of the spacecraft tape recorder, resulted in the successful return of 1645 unique images of Jupiter and its satellites