37 research outputs found
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North American Fauna 64
Examination of the body covering of the northern fur seal at each stage of growth as well as variations and anomalies
Experiments in the marking of seals and sea-lions
This report reviews experiments in the marking, for study purposes, of seals, sea-lions, and fur seals in the North Atlantic, North Pacific, and Antarctic regions. Also discussed are the results of studies of the northern fur seal, especially the series from 1940 to 1049 carried out by U.S. Government agents on the Pribilof Islands, Alaska. (PDF contains 38 pages
Technique of spinal cord compression induced by inflation of epidural balloon catheter in rabbits (Oryctologus cuniculus): efficient and easy to use model
Analysis of shared heritability in common disorders of the brain
ience, this issue p. eaap8757 Structured Abstract INTRODUCTION Brain disorders may exhibit shared symptoms and substantial epidemiological comorbidity, inciting debate about their etiologic overlap. However, detailed study of phenotypes with different ages of onset, severity, and presentation poses a considerable challenge. Recently developed heritability methods allow us to accurately measure correlation of genome-wide common variant risk between two phenotypes from pools of different individuals and assess how connected they, or at least their genetic risks, are on the genomic level. We used genome-wide association data for 265,218 patients and 784,643 control participants, as well as 17 phenotypes from a total of 1,191,588 individuals, to quantify the degree of overlap for genetic risk factors of 25 common brain disorders. RATIONALE Over the past century, the classification of brain disorders has evolved to reflect the medical and scientific communities' assessments of the presumed root causes of clinical phenomena such as behavioral change, loss of motor function, or alterations of consciousness. Directly observable phenomena (such as the presence of emboli, protein tangles, or unusual electrical activity patterns) generally define and separate neurological disorders from psychiatric disorders. Understanding the genetic underpinnings and categorical distinctions for brain disorders and related phenotypes may inform the search for their biological mechanisms. RESULTS Common variant risk for psychiatric disorders was shown to correlate significantly, especially among attention deficit hyperactivity disorder (ADHD), bipolar disorder, major depressive disorder (MDD), and schizophrenia. By contrast, neurological disorders appear more distinct from one another and from the psychiatric disorders, except for migraine, which was significantly correlated to ADHD, MDD, and Tourette syndrome. We demonstrate that, in the general population, the personality trait neuroticism is significantly correlated with almost every psychiatric disorder and migraine. We also identify significant genetic sharing between disorders and early life cognitive measures (e.g., years of education and college attainment) in the general population, demonstrating positive correlation with several psychiatric disorders (e.g., anorexia nervosa and bipolar disorder) and negative correlation with several neurological phenotypes (e.g., Alzheimer's disease and ischemic stroke), even though the latter are considered to result from specific processes that occur later in life. Extensive simulations were also performed to inform how statistical power, diagnostic misclassification, and phenotypic heterogeneity influence genetic correlations. CONCLUSION The high degree of genetic correlation among many of the psychiatric disorders adds further evidence that their current clinical boundaries do not reflect distinct underlying pathogenic processes, at least on the genetic level. This suggests a deeply interconnected nature for psychiatric disorders, in contrast to neurological disorders, and underscores the need to refine psychiatric diagnostics. Genetically informed analyses may provide important "scaffolding" to support such restructuring of psychiatric nosology, which likely requires incorporating many levels of information. By contrast, we find limited evidence for widespread common genetic risk sharing among neurological disorders or across neurological and psychiatric disorders. We show that both psychiatric and neurological disorders have robust correlations with cognitive and personality measures. Further study is needed to evaluate whether overlapping genetic contributions to psychiatric pathology may influence treatment choices. Ultimately, such developments may pave the way toward reduced heterogeneity and improved diagnosis and treatment of psychiatric disorders
Mima Mounds: A Reply
Major Grant believes that gophers behave in one way, and we believe that they behave in another-or we admit that we do not know exactly how they behave. I have plainly stated (1947, PP. 293, 294) that our evidence is indirect; that we have not seen gophers building a giant mound; that we do not know whether mound building is a contemporary or a historic process; and that we do not know whether the stimulus for mound building is a hardpan or a high water table or both.
Our main contentions are that mounds of the Mima type occur only within the range of gophers, living or extirpated, and that only a living, adaptable force, not a physical agency, could have produced the Mima-type mounds out of widely varying materials and in widely varying environments from Mexico to Puget Sound. We note that Chapman Grant does not propose an alternative theory for the origin of the mounds
Benign Uses of Wildlife
During the Age of Environmental Awareness, which dawned in the late 1960\u27s, Americans turned to using wild animals more benignly(or in ways harmless both to individuals and populations) and less exploitatively. The evidence includes: new federal legislation reflecting a public shift toward benign uses, growth. of interest in \u27nongame\u27 wildlife, growth of interest in wildlife watching (rate of increase in number of camera safaris estimated at 32 % per annum in 7 recent years), growth in membership of animal-interest organizations (rate of increase estimated at 7.7% per annum in 15 recent years), and growth of interest in animal rights. Per capita participation in sports hunting, an activity which long represented the dominant use of wildlife, is decreasing. Popular sentiment, as distinct from zoological and economic considerations, increasingly influences wildlife use decisions
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Letter to H.B. Stenzel from Victor B. Scheffer on 1965-07-21
Jackson School of Geoscience
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North American Fauna 61
Systematic account of the results of a survey made in 1936 and 1937 to aid supervision of the Aleutian Islands National Wildlife Refuge