205 research outputs found
Thermal Energy Generation in the Earth
We show that a recently introduced class of electromagnetic composite
particles can explain some discrepancies in observations involving heat and
helium released from the earth. Energy release during the formation of the
composites and subsequent nuclear reactions involving the composites are
described that can quantitatively account for the discrepancies and are
expected to have implications in other areas of geophysics, for example, a new
picture of heat production and volcanism in the earth is presented.Comment: 11 pages, 7 figure
On the exact electric and magnetic fields of an electric dipole
We derive from Jefimenko's equations a multipole expansion in order to obtain
the exact expressions for the electric and magnetic fields of an electric
dipole with an arbitrary time dependence. A few comments are also made about
the usual expositions found in most common undergraduate and graduate textbooks
as well as in the literature on this topic
Ernst Freund as Precursor of the Rational Study of Corporate Law
Gindis, David, Ernst Freund as Precursor of the Rational Study of Corporate Law (October 27, 2017). Journal of Institutional Economics, Forthcoming. Available at SSRN: https://ssrn.com/abstract=2905547, doi: https://dx.doi.org/10.2139/ssrn.2905547The rise of large business corporations in the late 19th century compelled many American observers to admit that the nature of the corporation had yet to be understood. Published in this context, Ernst Freund's little-known The Legal Nature of Corporations (1897) was an original attempt to come to terms with a new legal and economic reality. But it can also be described, to paraphrase Oliver Wendell Holmes, as the earliest example of the rational study of corporate law. The paper shows that Freund had the intuitions of an institutional economist, and engaged in what today would be called comparative institutional analysis. Remarkably, his argument that the corporate form secures property against insider defection and against outsiders anticipated recent work on entity shielding and capital lock-in, and can be read as an early contribution to what today would be called the theory of the firm.Peer reviewe
Historia de un campamento del Horizonte Medio de Huarmey, Perú (PV35-4)
Se presenta el estudio de un campamento temporal del Horizonte Medio situado en el desierto costero peruano al norte del valle de Huarmey. Se ha excavado la parte central del mismo pues presentaba la mayor cantidad de basura y dos fogones. Se ha podido establecer a base de la cerámica encontrada, que el sitio corresponde al Horizonte Medio 3. Los artefactos hallados son muy pocos, lo que es lógico dada la corta ocupación del sitio. Sin embargo se ha podido estudiar los abundantes restos botánicos y animales asà como los fecales de llama que estaban acumulados en el lugar. También se ha encontrado coprolitos humanos. De ambos se ha realizado el examen polÃnico. Además de los excrementos humanos se ha efectuado el análisis del contenido de plantas y animales asà como el parasitológico.Cet article étudie un campement temporaire de l’Horizon Moyen situé dans le désert côtier péruvien au nord de la vallée de Huarmey. La partie centrale du site a été choisie pour les fouilles car elle offrait la plus grande quantité de déchets ainsi que deux foyers. Il a été établi que le site correspondait à l’Horizon Moyen 3 grâce à la céramique qui y fut trouvée. Peu d’outillage a été trouvé en raison de la courte occupation du site, mais les restes abondants d’animaux et botaniques ainsi que les restes fécaux de llamas et humains accumulés sur le site ont fourni de précieuses indications. Les résultats des examens polliniques des coprolithes ainsi que les analyses du contenu de plantes, animaux et parasytes présents dans les coprolithes humains sont présentés ici.This is a study of a Middle Horizon temporary campsite located in the peruvian north coastal desert of the Huarmey Valley. The excavation was undertaken in the central part of the site since it contained the largest quantity debris and evidence of two bonfires. Its age was established using pieces of ceramic found on the site. A few artifacts were founded, probably due to the brief occupancy of the site, but were able to study the abundant botanical and animal remains, as well as llama and human coprolites. We present the results of tests for pollen in both the llama and human coprolites, as well as of tests for plant, animal, and parasite content in the human fecal remains are presented here
Does Time Since Immigration Modify Neighborhood Deprivation Gradients in Preterm Birth? A Multilevel Analysis
Immigrants’ health is jointly influenced by their pre- and post-migration exposures, but how these two influences operate with increasing duration of residence has not been well-researched. We aimed to examine how the influence of maternal country of birth and neighborhood deprivation effects, if any, change over time since migration and how neighborhood effects among immigrants compare with those observed in the Canadian-born population. Birth data from Ontario hospital records (2002–2007) were linked with an official Canadian immigration database (1985–2000). The outcome measure was preterm birth. Neighborhoods were ranked according to a neighborhood deprivation index developed for Canadian urban areas and collapsed into tertiles of approximately equal size. Time since immigration was measured from the date of arrival to Canada to the date of delivery, ranging from 1 to 22 years. We used cross-classified random effect models to simultaneously account for the membership of births (N = 83,233) to urban neighborhoods (N = 1,801) and maternal countries of birth (N = 168). There were no differences in preterm birth between neighborhood deprivation tertiles among immigrants with less than 15 years of residence. Among immigrants with 15 years of stay or more, the adjusted absolute risk difference (ARD%, 95% confidence interval) between high-deprived (tertile 3) and low-deprived (tertile 1) neighborhoods was 1.86 (0.68, 2.98), while the ARD% observed among the Canadian-born (N = 314,237) was 1.34 (1.11, 1.57). Time since migration modifies the neighborhood deprivation gradient in preterm birth among immigrants living in Ontario cities. Immigrants reached the level of inequalities in preterm birth observed at the neighborhood level among the Canadian-born after 14 years of stay, but neighborhoods did not influence preterm birth among more recent immigrants, for whom the maternal country of birth was more predictive of preterm birth
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Common genetic variants in the CLDN2 and PRSS1-PRSS2 loci alter risk for alcohol-related and sporadic pancreatitis
Pancreatitis is a complex, progressively destructive inflammatory disorder. Alcohol was long thought to be the primary causative agent, but genetic contributions have been of interest since the discovery that rare PRSS1, CFTR, and SPINK1 variants were associated with pancreatitis risk. We now report two significant genome-wide associations identified and replicated at PRSS1-PRSS2 (1×10-12) and x-linked CLDN2 (p < 1×10-21) through a two-stage genome-wide study (Stage 1, 676 cases and 4507 controls; Stage 2, 910 cases and 4170 controls). The PRSS1 variant affects susceptibility by altering expression of the primary trypsinogen gene. The CLDN2 risk allele is associated with atypical localization of claudin-2 in pancreatic acinar cells. The homozygous (or hemizygous male) CLDN2 genotype confers the greatest risk, and its alleles interact with alcohol consumption to amplify risk. These results could partially explain the high frequency of alcohol-related pancreatitis in men – male hemizygous frequency is 0.26, female homozygote is 0.07
Convergent genetic and expression data implicate immunity in Alzheimer's disease
Background
Late–onset Alzheimer's disease (AD) is heritable with 20 genes showing genome wide association in the International Genomics of Alzheimer's Project (IGAP). To identify the biology underlying the disease we extended these genetic data in a pathway analysis.
Methods
The ALIGATOR and GSEA algorithms were used in the IGAP data to identify associated functional pathways and correlated gene expression networks in human brain.
Results
ALIGATOR identified an excess of curated biological pathways showing enrichment of association. Enriched areas of biology included the immune response (p = 3.27×10-12 after multiple testing correction for pathways), regulation of endocytosis (p = 1.31×10-11), cholesterol transport (p = 2.96 × 10-9) and proteasome-ubiquitin activity (p = 1.34×10-6). Correlated gene expression analysis identified four significant network modules, all related to the immune response (corrected p 0.002 – 0.05).
Conclusions
The immune response, regulation of endocytosis, cholesterol transport and protein ubiquitination represent prime targets for AD therapeutics
Rare coding variants in PLCG2, ABI3, and TREM2 implicate microglial-mediated innate immunity in Alzheimer's disease
We identified rare coding variants associated with Alzheimer’s disease (AD) in a 3-stage case-control study of 85,133 subjects. In stage 1, 34,174 samples were genotyped using a whole-exome microarray. In stage 2, we tested associated variants (P<1×10-4) in 35,962 independent samples using de novo genotyping and imputed genotypes. In stage 3, an additional 14,997 samples were used to test the most significant stage 2 associations (P<5×10-8) using imputed genotypes. We observed 3 novel genome-wide significant (GWS) AD associated non-synonymous variants; a protective variant in PLCG2 (rs72824905/p.P522R, P=5.38×10-10, OR=0.68, MAFcases=0.0059, MAFcontrols=0.0093), a risk variant in ABI3 (rs616338/p.S209F, P=4.56×10-10, OR=1.43, MAFcases=0.011, MAFcontrols=0.008), and a novel GWS variant in TREM2 (rs143332484/p.R62H, P=1.55×10-14, OR=1.67, MAFcases=0.0143, MAFcontrols=0.0089), a known AD susceptibility gene. These protein-coding changes are in genes highly expressed in microglia and highlight an immune-related protein-protein interaction network enriched for previously identified AD risk genes. These genetic findings provide additional evidence that the microglia-mediated innate immune response contributes directly to AD development
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