Deep-tow magnetic anomaly study of the Pacific Jurassic Quiet Zone and implications for the geomagnetic polarity reversal timescale and geomagnetic field behavior

Author Posting. © American Geophysical Union, 2008. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research 113 (2008): B07110, doi:10.1029/2007JB005527.The Jurassic Quiet Zone (JQZ) is a region of low-amplitude magnetic anomalies whose distinctive character may be related to geomagnetic field behavior. We collected deep-tow magnetic profiles in Pigafetta Basin (western Pacific) where previous deep-tow data partially covered the JQZ sequence. Our goals were to extend the survey through the JQZ, examine anomaly correlations, and refine a preliminary geomagnetic polarity timescale (GPTS) model. We collected a series of closely spaced profiles over anomaly M34 and Ocean Drilling Program Hole 801C to examine anomaly correlation in detail, one profile in between previous profiles, and two long profiles extending the survey deeper into the JQZ. Anomaly features can be readily correlated except in a region of low-amplitude, short-wavelength anomalies in the middle of the survey area (“low-amplitude zone” or LAZ). The small multiprofile surveys demonstrate anomaly linearity, implying that surrounding anomalies are also linear and likely result from crustal recording of geomagnetic field changes. We constructed a GPTS model assuming that most anomalies result from polarity reversals. The polarity timescale is similar to the polarity sequences from previous studies, but its global significance is uncertain because of problems correlating anomalies in the LAZ and the ambiguous nature of the small JQZ anomalies. Overall anomaly amplitude decreases with age into the LAZ and then increases again, implying low geomagnetic field strength, perhaps related to a rapidly reversing field. Other factors that may contribute to the LAZ are interference of anomalies over narrow, crustal polarity zones and poorly understood local tectonic complexities.This research was supported by the National Science Foundation grants OCE-0099161 and OCE-0099237. Tominaga was partly supported by funds from the Jane and R. Ken Williams ’45 Chair in Ocean Drilling Science, Education, and Technology

Tetrameric Complexes of Human Histocompatibility Leukocyte Antigen (HLA)-G Bind to Peripheral Blood Myelomonocytic Cells

The nonclassical MHC class I molecule human histocompatibility leukocyte antigen (HLA)-G is selectively expressed on fetal trophoblast tissue at the maternal–fetal interface in pregnancy. It has long been suggested that HLA-G may inhibit maternal natural killer (NK) cells through interaction with particular NK cell receptors (KIRs). To investigate interactions of HLA-G, we constructed phycoerythrin-labeled tetrameric complexes of HLA-G refolded with a self-peptide. These HLA-G tetramers failed to bind to NK cells and cells transfected with CD94/NKG2 and killer immunoglobulin-like NK receptors. In contrast, HLA-G tetramers did bind to peripheral blood monocytes, staining a CD16+CD14mid subset with greater intensity. On transfectants, HLA-G tetramers bound to inhibitory immunoglobulin-like transcript (ILT)2 and ILT4 receptors. However, staining in the presence of antibodies reactive with ILT receptors revealed that the interaction of HLA-G tetramers with blood monocytes was largely due to binding to ILT4. These results suggest that the primary role of HLA-G may be the modulation of myelomonocytic cell behavior in pregnancy

Social exclusion of older persons: a scoping review and conceptual framework

As a concept, social exclusion has considerable potential to explain and respond to disadvantage in later life. However, in the context of ageing populations, the construct remains ambiguous. A disjointed evidence-base, spread across disparate disciplines, compounds the challenge of developing a coherent understanding of exclusion in older age. This article addresses this research deficit by presenting the findings of a two-stage scoping review encompassing seven separate reviews of the international literature pertaining to old-age social exclusion. Stage one involved a review of conceptual frameworks on old-age exclusion, identifying conceptual understandings and key domains of later-life exclusion. Stage two involved scoping reviews on each domain (six in all). Stage one identified six conceptual frameworks on old-age exclusion and six common domains across these frameworks: neighbourhood and community; services, amenities and mobility; social relations; material and financial resources; socio-cultural aspects; and civic participation. International literature concentrated on the first four domains, but indicated a general lack of research knowledge and of theoretical development. Drawing on all seven scoping reviews and a knowledge synthesis, the article presents a new definition and conceptual framework relating to old-age exclusion