The energetics of migration and reproduction of dusky Canada geese (Branta canadensis occidentalis)

Adult female Dusky Canada Geese were studied on the Copper River Delta, Alaska and in the Willamette Valley, Oregon during April through July, 1977 to 1979. Objectives of the research were to: 1) determine the chronology of use of protein and energy reserves in relation to four periods of reproduction defined as the migration, prelaying, egg laying and incubation periods, and 2) to assess the role of food in meeting energy requirements during these four periods. During the study, 162 geese were collected for composition analysis. Endogenous lipids were heavily utilized during migration, egg laying and incubation. Endogenous protein was important during egg laying and incubation. Food supplied about half of the energy requirements calculated for the migration period, all needs during prelaying, over 75% during egg laying and about one third of energy requirements during incubation. Food was most important for supplementing high' protein needs of laying geese and both protein and energy needs of geese during the last third of the incubation period when endogenous reserves were depleted. Although northern nesting geese have been assumed to be largely independent of food during prelaying through incubation, it was suggested that food is in fact proximately important, influencing both clutch size and patterns of energy use during incubation. Ultimately, the timing of nesting and clutch size of northern nesting geese may have evolved in response to the need for an optimal food supply about two-thirds of the way through incubation

Problems in Interpreting Unusually Large Burrows

Although marine burrows of unusually large dimensions have long been known in certain areas, they are probably much more widespread in the rock record than is generally recognized. Such burrows constitute a heterogeneous group, having little in common other than exceptional size. Yet their size alone unites them in difficulty of interpretation: e.g., densely spaced-dwelling burrows of combined dwelling-escape burrows as much as 12 cm in diameter and 5 m long; vertical dwelling burrows only 0.5 cm in diameter but up to 9 m long; possible escape structures as much as 24 cm in diameter and 3 m long, subsequently penetrated in some cases by secondary burrow-like structures. Numerous special problems are encountered in the study and interpretation of burrows of these extreme dimensions: (1) field exposure and accessibility, so that the full extent, or a large part, of the structures can be studied; (2) preservation of the burrows in continuity, not merely in places where they pass through certain beds or within concretion horizons; (3) the fossilization barrier ; our knowledge of comparable modern structures of similar dimensions or of the animals responsible for them is negligible; and (4) the possibility that certain of these unusual structures were formed by physical rather than organic processes; again, our criteria for comparisons are limited. The examples selected by us—from the Permian of Montana, Idaho, and Wyoming, the Cretaceous and Paleocene of northwestern Europe, and the Pleistocene of North Carolina—are intended primarily (1) to call additional attention to such intriguing structures, and (2) to illustrate some of the problems involved in interpreting their origin and function. Hopefully, future work will solve many of these problems

The Periodic Standing-Wave Approximation: Overview and Three Dimensional Scalar Models

The periodic standing-wave method for binary inspiral computes the exact numerical solution for periodic binary motion with standing gravitational waves, and uses it as an approximation to slow binary inspiral with outgoing waves. Important features of this method presented here are: (i) the mathematical nature of the ``mixed'' partial differential equations to be solved, (ii) the meaning of standing waves in the method, (iii) computational difficulties, and (iv) the ``effective linearity'' that ultimately justifies the approximation. The method is applied to three dimensional nonlinear scalar model problems, and the numerical results are used to demonstrate extraction of the outgoing solution from the standing-wave solution, and the role of effective linearity.Comment: 13 pages RevTeX, 5 figures. New version. A revised form of the nonlinearity produces better result

Spectral Classification and Luminosity Function of Galaxies in the Las Campanas Redshift Survey

We construct a spectral classification scheme for the galaxies of the Las Campanas Redshift Survey (LCRS) based on a principal component analysis of the measured galaxy spectra. We interpret the physical significance of our six spectral types and conclude that they are sensitive to morphological type and the amount of active star formation. In this first analysis of the LCRS to include spectral classification, we estimate the general luminosity function, expressed as a weighted sum of the type-specific luminosity functions. In the R-band magnitude range of -23 < M <= -16.5, this function exhibits a broad shoulder centered near M = -20, and an increasing faint-end slope which formally converges on an alpha value of about -1.8 in the faint limit. The Schechter parameterization does not provide a good representation in this case, a fact which may partly explain the reported discrepancy between the luminosity functions of the LCRS and other redshift catalogs such as the Century Survey (Geller et al. 1997). The discrepancy may also arise from environmental effects such as the density-morphology relationship for which we see strong evidence in the LCRS galaxies. However, the Schechter parameterization is more effective for the luminosity functions of the individual spectral types. The data show a significant, progressive steepening of the faint-end slope, from alpha = +0.5 for early-type objects, to alpha = -1.8 for the extreme late-type galaxies. The extreme late-type population has a sufficiently high space density that its contribution to the general luminosity function is expected to dominate fainter than M = -16. We conclude that an evaluation of type-dependence is essential to any assessment of the general luminosity function.Comment: 21 pages (LaTeX), 7 figures (Postscript). To appear in the Astrophysical Journal. The discussion of environmental dependence of luminosity functions has been shortened; the material from the earlier version now appears in a separate manuscript (astro-ph/9805197

The use of interpretive phenomenological analysis in couple and family therapy research

This article proposes a research methodology that is newer to the field of couple and family therapy research called Interpretive Phenomenological Analysis (IPA). Researchers exploring couple and family therapy research continue to establish the efficacy of couple and family interventions in a context that favors a positivist view of phenomena. This research continues to be critical for establishing the role of couple and family therapy in the field of mental health as well as further clarifying which interventions are best for specific clinical issues and when. IPA offers researchers the opportunity to explore how couples and families make meaning of their experiences from an intersubjective perspective. Meaning making is central to understanding couples and families as well as part of the many clinical approaches to working with couples and families. Despite the importance of meaning, few research methodologies allow for this central concept in couple and family therapy to be the focus of exploration. The following article outlines one such methodology and the possible use of IPA in couple and family therapy research

Association of Genetic Variants With Primary Open-Angle Glaucoma Among Individuals With African Ancestry.

Importance:Primary open-angle glaucoma presents with increased prevalence and a higher degree of clinical severity in populations of African ancestry compared with European or Asian ancestry. Despite this, individuals of African ancestry remain understudied in genomic research for blinding disorders. Objectives:To perform a genome-wide association study (GWAS) of African ancestry populations and evaluate potential mechanisms of pathogenesis for loci associated with primary open-angle glaucoma. Design, Settings, and Participants:A 2-stage GWAS with a discovery data set of 2320 individuals with primary open-angle glaucoma and 2121 control individuals without primary open-angle glaucoma. The validation stage included an additional 6937 affected individuals and 14 917 unaffected individuals using multicenter clinic- and population-based participant recruitment approaches. Study participants were recruited from Ghana, Nigeria, South Africa, the United States, Tanzania, Britain, Cameroon, Saudi Arabia, Brazil, the Democratic Republic of the Congo, Morocco, Peru, and Mali from 2003 to 2018. Individuals with primary open-angle glaucoma had open iridocorneal angles and displayed glaucomatous optic neuropathy with visual field defects. Elevated intraocular pressure was not included in the case definition. Control individuals had no elevated intraocular pressure and no signs of glaucoma. Exposures:Genetic variants associated with primary open-angle glaucoma. Main Outcomes and Measures:Presence of primary open-angle glaucoma. Genome-wide significance was defined as P &lt; 5 × 10-8 in the discovery stage and in the meta-analysis of combined discovery and validation data. Results:A total of 2320 individuals with primary open-angle glaucoma (mean [interquartile range] age, 64.6 [56-74] years; 1055 [45.5%] women) and 2121 individuals without primary open-angle glaucoma (mean [interquartile range] age, 63.4 [55-71] years; 1025 [48.3%] women) were included in the discovery GWAS. The GWAS discovery meta-analysis demonstrated association of variants at amyloid-β A4 precursor protein-binding family B member 2 (APBB2; chromosome 4, rs59892895T&gt;C) with primary open-angle glaucoma (odds ratio [OR], 1.32 [95% CI, 1.20-1.46]; P = 2 × 10-8). The association was validated in an analysis of an additional 6937 affected individuals and 14 917 unaffected individuals (OR, 1.15 [95% CI, 1.09-1.21]; P &lt; .001). Each copy of the rs59892895*C risk allele was associated with increased risk of primary open-angle glaucoma when all data were included in a meta-analysis (OR, 1.19 [95% CI, 1.14-1.25]; P = 4 × 10-13). The rs59892895*C risk allele was present at appreciable frequency only in African ancestry populations. In contrast, the rs59892895*C risk allele had a frequency of less than 0.1% in individuals of European or Asian ancestry. Conclusions and Relevance:In this genome-wide association study, variants at the APBB2 locus demonstrated differential association with primary open-angle glaucoma by ancestry. If validated in additional populations this finding may have implications for risk assessment and therapeutic strategies

Erratum to: Methods for evaluating medical tests and biomarkers

[This corrects the article DOI: 10.1186/s41512-016-0001-y.]

Evidence synthesis to inform model-based cost-effectiveness evaluations of diagnostic tests: a methodological systematic review of health technology assessments

Background: Evaluations of diagnostic tests are challenging because of the indirect nature of their impact on patient outcomes. Model-based health economic evaluations of tests allow different types of evidence from various sources to be incorporated and enable cost-effectiveness estimates to be made beyond the duration of available study data. To parameterize a health-economic model fully, all the ways a test impacts on patient health must be quantified, including but not limited to diagnostic test accuracy. Methods: We assessed all UK NIHR HTA reports published May 2009-July 2015. Reports were included if they evaluated a diagnostic test, included a model-based health economic evaluation and included a systematic review and meta-analysis of test accuracy. From each eligible report we extracted information on the following topics: 1) what evidence aside from test accuracy was searched for and synthesised, 2) which methods were used to synthesise test accuracy evidence and how did the results inform the economic model, 3) how/whether threshold effects were explored, 4) how the potential dependency between multiple tests in a pathway was accounted for, and 5) for evaluations of tests targeted at the primary care setting, how evidence from differing healthcare settings was incorporated. Results: The bivariate or HSROC model was implemented in 20/22 reports that met all inclusion criteria. Test accuracy data for health economic modelling was obtained from meta-analyses completely in four reports, partially in fourteen reports and not at all in four reports. Only 2/7 reports that used a quantitative test gave clear threshold recommendations. All 22 reports explored the effect of uncertainty in accuracy parameters but most of those that used multiple tests did not allow for dependence between test results. 7/22 tests were potentially suitable for primary care but the majority found limited evidence on test accuracy in primary care settings. Conclusions: The uptake of appropriate meta-analysis methods for synthesising evidence on diagnostic test accuracy in UK NIHR HTAs has improved in recent years. Future research should focus on other evidence requirements for cost-effectiveness assessment, threshold effects for quantitative tests and the impact of multiple diagnostic tests

Erratum to: Methods for evaluating medical tests and biomarkers

[This corrects the article DOI: 10.1186/s41512-016-0001-y.]