Use of Hydration Inhibitors to Improve Bond Durability of Aluminum Adhesive Joints

An investigation is conducted of the mechanisms by which nitrilotris methylene phosphonic acid (NTMP) and related compounds are adsorbed onto oxidized aluminum surfaces to inhibit hydration and increase the durability of adhesive bonds formed with inhibitor-treated panels. P - O - Al bonds are identified as the basis of adsorption, and it is found that water initially adsorbed onto the etched aluminum surfaces is displaced by the NTMP. The hydration of the NTMP-treated surfaces occurs in three stages, namely the reverisble physisorption of water, the slow dissolution of NTMP followed by rapid hydration of the freshly exposed Al2O3 to AlOOH and further hydration of the surface to Al(OH)3. Five properties of an ideal inhibitor are identified

REGIONAL DIFFERENCES IN THE CONTRIBUTION OF OFF-FARM WORK TO INCOME INEQUALITY

This paper uses the concept of the Gini Coefficient and data from the 1991 Farm Costs and Returns Survey (FCRS) to measure the role of off-farm income and that of other income sources in the size distribution of farm operator households' total personal income. Disaggregated FCRS data by region and by level of participation in off-farm employment show that nonparticipating farm operator households have, as a group, higher income inequality than participating households. The results also indicate that, irrespective of the off-farm work status of the farm operator household, the distribution of income among households in the North Central region is least unequal and that in the West is most unequal.Labor and Human Capital,

Age Related Changes in Cerebrovascular Reactivity and Its Relationship to Global Brain Structure

ACKNOWLEDGMENTS This study was funded by Alzheimer’s Research UK (ARUK) and the Aberdeen Biomedical Imaging Centre, University of Aberdeen. GDW, ADM and CS are part of the SINASPE collaboration (Scottish Imaging Network - A Platform for Scientific Excellence www.SINAPSE.ac.uk). The authors thank Gordon Buchan, Baljit Jagpal, Nichola Crouch, Beverly Maclennan and Katrina Klaasen for their help with running the experiment and Dawn Younie and Teresa Morris for their help with recruitment and scheduling. We also thank the residents of Aberdeen and Aberdeenshire, and further afield, for their generous participation.Peer reviewedPublisher PD

The 15 years of comet photometry: A comparative analysis of 80 comets

In 1976, a program of narrowband photometry of comets was initiated that has encompassed well over 400 nights of observations. To date, the program has provided detailed information on 80 comets, 11 of which were observed during multiple apparitions. The filters (initially isolating CN, C2, and continuum and later including C3, OH, and NH) as well as the detectors used for the observations were changed over time, and the parameters adopted in the reduction and modeling of the data have likewise evolved. Accordingly, we have re-reduced the entire database and have derived production rates using current values for scalelengths and fluorescence efficiencies. Having completed this task, the results for different comets can now be meaningfully compared. The general characteristics that are discussed include ranges in composition (molecular production rate ratios) and dustiness (gas production compared with Af(rho)). Additionally an analysis of trends on how the production rates vary with heliocentric distance and on pre- and post-perihelion asymmetries in the production rates of individual comets. Possible taxonomic groupings are also described

The 13 November 1984 occultation of BD +08 deg 0471 by (1) Ceres

The 13 November 1984 occultation of BD +08 deg 0471 was discovered during a photographic search carried out with the 0.5 meter Carnegie Double Astrograph at Lick Observatory and the Lowell Observatory PDS microdensitometer. Such a search was stimulated by the curious fact that few favorably located occultations of AGK3 or SAO catalog starts by Ceres will occur during the 1980s. The occultation on 13 November, however, is a particularly good event. The star is 1000 cubic M in V, yielding a predicted drop at occultation of about 10%. Such a drop can be detected by small telescopes equipped with photoelectric photometers, but is too small to be seen visually. The track was predicted to cross the Caribbean, Florida, southern Texas, and Mexico. Based on this prediction, preparations were made to observe the event in Mexico using four portable occultation data systems

Sex differences in the association of photoperiod with hippocampal subfield volumes in older adults : A crosssectional study in the UK Biobank cohort

© 2020 The Authors. Brain and Behavior published by Wiley Periodicals, Inc.Peer reviewedPublisher PD

Fuzzy approximate entropy analysis of resting state fMRI signal complexity across the adult life span

Acknowledgment The authors would like to acknowledge the work of the International Consortium for Brain Mapping (ICBM) fMRI community in creating the resting state database and making it publicly available within the framework of the 1000 Functional Connectomes project (https://www.nitrc.org/projects/fcon_1000/). M.O. Sokunbi was supported by an MRC grant G1100629.Peer reviewedPreprin

Rap1 up-regulation and activation on plasma membrane regulates T cell adhesion

Rap1 and Ras are closely related GTPases that share some effectors but have distinct functions. We studied the subcellular localization of Rap1 and its sites of activation in living cells. Both GFP-tagged Rap1 and endogenous Rap1 were localized to the plasma membrane (PM) and endosomes. The PM association of GFP-Rap1 was dependent on GTP binding, and GFP-Rap1 was rapidly up-regulated on this compartment in response to mitogens, a process blocked by inhibitors of endosome recycling. A novel fluorescent probe for GTP-bound Rap1 revealed that this GTPase was transiently activated only on the PM of both fibroblasts and T cells. Activation on the PM was blocked by inhibitors of endosome recycling. Moreover, inhibition of endosome recycling blocked the ability of Rap1 to promote integrin-mediated adhesion of T cells. Thus, unlike Ras, the membrane localizations of Rap1 are dynamically regulated, and the PM is the principle platform from which Rap1 signaling emanates. These observations may explain some of the biological differences between these GTPases

N,N′-Bis(2,2,3,3,4,4,4-hepta­fluoro­butyl)naphthalene-1,4:5,8-tetra­carboximide

The title mol­ecule, C22H8F14N2O4, lies across a crystallographic inversion center with the naphthalene diimide core essentially planar (mean deviation from plane is 0.0583 Å). The CF2 groups in the perfluorobutyl chains are in an energetically favorable all trans conformation. In the crystal structure, mol­ecules are packed in slightly displaced layers so that the side chains overlap the aromatic naphthalene diimide rings, thus minimizing any possible π–π overlap

Disruption of the Cr2 Locus Results in a Reduction in B-1a Cells and in an Impaired B Cell Response to T-Dependent Antigen

AbstractCovalent attachment of activated products of the third component of complement to antigen enhances its immunogenicity, but the mechanism is not clear. This effect is mediated by specific receptors, mCR1 (CD35) and mCR2 (CD21), expressed primarily on B cells and follicular dendritic cells in mice. To dissect the role of mCR1 and mCR2 in the humoral response, we have disrupted the Cr2 locus to generate mice deficient in both receptors. The deficient mice (Cr2−/−) were found to have a reduction in the CD5+ population of peritoneal B-1 cells, although their serum IgM levels were within the range of normal mice. Moreover, Cr2−/− mice had a severe defect in their humoral response to T-dependent antigens that was characterized by a reduction in serum antibody titers and in the number and size of germinal centers within splenic follicles. Reconstitution of the deficient mice with bone marrow from MHC-matched Cr2+/+ donors corrected the defect, demonstrating that the defect was due to B cells themselves. These results indicate an obligatory role of B cell complement receptors in responses of the B cells to protein antigens