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1.
Polit Q ; 93(2): 316-325, 2022.
Article in English | MEDLINE | ID: mdl-35600738

ABSTRACT

Crises like the Covid-19 pandemic place an added premium on the social contract underpinning principal-agent relations in representative democracies, which relies, at a fundamental level, on conditional trust judgements by those without power in those with decision-making authority to act in their better interests. Existing studies of political trust during the pandemic suggest that it has been both a symptom of government activity as well as a cause of its success or failure. Presenting original longitudinal data collected from UK citizens at the start of the pandemic and again twenty months later, the article teases apart these dynamics and their implications. It shows, for example, that the public became less trusting and more distrusting of politicians during this unique moment, and that these trends are strongly linked to performance evaluations of the UK government as well as public compliance with mandatory and non-mandatory policies such as vaccination and mask wearing.

2.
Br Politics ; 17(2): 185-209, 2022.
Article in English | MEDLINE | ID: mdl-38624596

ABSTRACT

Entrenched inequalities in political participation have made the questions of who participates and when, why, or how some of the most frequently asked and researched in political science. Building on existing comparative research, this article focuses on civic education in English secondary schools and, in particular, the ability of related interventions to close participation gaps normally seen by sex, ethnicity and socio-economic status. Analysing original survey data collected from more than 350 students in 17 maintained secondary schools located in six regions of England, this article evaluates the impact of four types of civic education (curricula lessons; open classroom climate; participatory activities; and political contact) on three participatory outcomes (expressive political behaviours; voting intentions; and anticipated high-intensity participation). Descriptive and inferential analyses suggest (a) cumulative quantities of civic education are positively associated with youth political participation; (b) open classroom climate may close known inequalities in young people's expressive and electoral participation whilst political contact with politicians and political institutions may widen those inequalities; and (c) civic education may currently accelerate inequalities in young people's political ambition. These findings raise important and immediate challenges for policy-makers who are concerned with improving young people's civic engagement in England and elsewhere. Supplementary Information: The online version contains supplementary material available at 10.1057/s41293-021-00186-4.

3.
Emotion ; 16(6): 897-902, 2016 09.
Article in English | MEDLINE | ID: mdl-27148848

ABSTRACT

Visceral states like thirst, hunger, and fatigue can alter motivations, predictions, and even memory. Across 3 studies, we demonstrate that such "hot" states can also shift moral standards and increase dishonest behavior. Compared to participants who had just eaten or who had not yet exercised, hungry and thirsty participants were more likely to behave dishonestly to win a prize. Consistent with the specificity of motivation that is characteristic of visceral states, participants were only more likely to cheat for a prize that could alleviate their current deprived state (such as a bottle of water). Interestingly, this increase in dishonest behavior did not seem to be driven by an increase in the perceived monetary value of the prize. (PsycINFO Database Record


Subject(s)
Deception , Decision Making/ethics , Fatigue/physiopathology , Hunger/physiology , Motivation/ethics , Thirst/physiology , Adult , Female , Humans , Male , Morals , Young Adult
4.
J Neurointerv Surg ; 7(11): 855-60, 2015 Nov.
Article in English | MEDLINE | ID: mdl-25200246

ABSTRACT

OBJECTIVE: Aneurysmal subarachnoid hemorrhage (aSAH) is a devastating illness with nationwide mortality rates reaching almost 50% within the first 30 days. A study was undertaken to evaluate how treatment modality, physical findings, and geo-demography contribute to the outcome of these cases, including complications and disposition status. METHODS: All cases of aSAH in the fiscal year of 2012 (July 2011-June 2012) at the Medical University of South Carolina and Palmetto Health Richland were studied. These healthcare facilities represent 88.5% of aneurysm treatment in the state of South Carolina. Information including aneurysm properties, Hunt-Hess grade, Fisher grade, and symptoms occurring at and after admission were analyzed. RESULTS: 131 patients (94 women and 37 men) with aSAH were treated. 92.4% of cases were treated endovascularly, with more than a third of all cases using balloon-assisted coiling. Hypertension, tobacco use, and hyperlipidemia were the most prevalent comorbidities. Headache, followed by hydrocephalus, motor disturbance, and nausea/vomiting were the most common presenting symptoms. The most common adverse event occurring after hospital admission was acute respiratory failure followed by urinary tract infection, hydrocephalus, and vasospasm. 42.0% were discharged home and nine patients (6.9%) died during hospitalization. CONCLUSIONS: Previously established risk factors such as hypertension and smoking were identified as the most prevalent comorbidities, with disparity between subgroups, particularly women and African Americans. Endovascular treatment was the primary modality of treatment. Mortality rates were lower than previously reported.


Subject(s)
Outcome Assessment, Health Care , Subarachnoid Hemorrhage , Black or African American/ethnology , Aneurysm, Ruptured/complications , Aneurysm, Ruptured/epidemiology , Female , Humans , Incidence , Male , Middle Aged , Risk Factors , Severity of Illness Index , Sex Factors , Socioeconomic Factors , South Carolina/epidemiology , Subarachnoid Hemorrhage/epidemiology , Subarachnoid Hemorrhage/mortality , Subarachnoid Hemorrhage/pathology , Subarachnoid Hemorrhage/therapy
5.
Int J Geriatr Psychiatry ; 24(8): 829-36, 2009 Aug.
Article in English | MEDLINE | ID: mdl-19551696

ABSTRACT

BACKGROUND: Structural abnormalities of the anterior cingulate cortex (ACC) may interfere with the interaction of cortical and limbic networks involved in emotional regulation and contribute to chronic depressive syndromes in the elderly. This study examined the relationship of regional anterior cingulate cortical volumes with treatment remission of elderly depressed patients. We hypothesized that patients who failed to remit during a 12-week controlled treatment trial of escitalopram would exhibit smaller anterior cingulate gray matter volumes than patients who remitted. METHODS: The participants were 41 non-demented individuals with non-psychotic major depression. After a 2-week single-blind placebo period, subjects who still had a Hamilton Depression Rating Scale (HDRS) of 18 or greater received escitalopram 10 mg daily for 12 weeks. Remission was defined as a HDRS score of 7 or below for at least 2 consecutive weeks. The patient sample consisted of 22 depressed patients who achieved remission during the study and 19 depressed patients who remained symptomatic. High-resolution magnetization-prepared rapidly acquired gradient echo (MPRAGE) sequences were acquired on a 1.5 T scanner and regional ACC volumes were manually outlined (dorsal, rostral, anterior subgenual, and posterior subgenual). RESULTS: Repeated measure analyses revealed that patients who failed to remit following escitalopram treatment had smaller dorsal and rostral anterior cingulate gray matter volumes than patients who remitted, whereas subgenual cortical volumes did not differ between the groups. CONCLUSIONS: Structural abnormalities of the dorsal and rostral anterior cingulate may perpetuate late-life depression.


Subject(s)
Depressive Disorder, Major/pathology , Gyrus Cinguli/pathology , Aged , Analysis of Variance , Antidepressive Agents, Second-Generation/therapeutic use , Citalopram/therapeutic use , Depressive Disorder, Major/drug therapy , Humans , Magnetic Resonance Imaging , Middle Aged , Organ Size , Remission Induction , Risk Factors , Single-Blind Method
6.
J Cardiovasc Transl Res ; 2(1): 30-8, 2009 Mar.
Article in English | MEDLINE | ID: mdl-20559967

ABSTRACT

Nanoparticles are increasingly used to label cells to track them by imaging or to quantify them in vivo. However, normal cellular uptake mechanisms are inadequate to load cells with tracking label. We propose a simple method to coat nanoparticles, such as monocrystalline iron oxide nanoparticle (MION), with the transfection agent polylysine in order to facilitate rapid, uniform, and heavy labeling of fibroblasts. The method is based on commercially available reagents, requires no more than 1 h of laboratory contact time, and can be accomplished safely without a chemical hood. A suspension of MION was treated by addition of solid sodium periodate to oxidize glucose residues of dextran and introduced aldehyde groups to the dextran coat surrounding MION's crystalline magnetite core. After a 30-min incubation to effect oxidation, unreacted periodate was quenched with glycerol. The preparation was dialyzed to remove reactants and diluted to a final concentration of 2 mg Fe/ml. Poly-L-lysine was added to the oxidized MION (MION-A) to form reversible covalent Schiff base linkages. The resulting conjugate, a polylysine iron oxide nano-particle is abbreviated PLION. NIH3T3 fibroblasts labeled with either MION, MION-A, or MION plus polylysine showed minimal uptake of iron while cells labeled with PLION acquired a brown hue demonstrating strong labeling with iron. Microscopic assessment of iron labeling was confirmed using Prussian blue staining. In some cells, the concentration of iron was sufficiently high and localized to suggest association with cytoplasmic vacuoles. The nucleus of the cell was not labeled. Cell labeling increased when the ratio of polylysine to MION increased and with increasing amount of PLION.


Subject(s)
Fibroblasts/metabolism , Metal Nanoparticles , Molecular Imaging/methods , Polylysine/chemical synthesis , Animals , Biological Transport , Ferrosoferric Oxide/chemical synthesis , Ferrosoferric Oxide/metabolism , Indicators and Reagents/chemical synthesis , Kinetics , Mice , Microscopy , NIH 3T3 Cells , Nanoparticles , Oxidation-Reduction , Polylysine/metabolism
7.
J Cardiovasc Transl Res ; 1(3): 217-20, 2008 Sep.
Article in English | MEDLINE | ID: mdl-20559922

ABSTRACT

Tracking cells in regenerative medicine is becoming increasingly important for basic cell therapy science, for cell delivery optimization and for accurate biodistribution studies. This report describes nanoparticles that utilize stable-isotope metal labels for multiple detection technologies in preclinical studies. Cells labeled with nanoparticles can be imaged by electron microscopy, fluorescence, and magnetic resonance. The nanoparticle-labeled cells can be quantified by neutron activation, thereby allowing, with the use of standard curves, the determination of the number of labeled cells in tissue samples from in vivo sources. This report describes the characteristics of these nanoparticles and methods for using these nanoparticles to label and track cells.


Subject(s)
Cell Movement , Cell Transplantation , Nanoparticles , Regenerative Medicine/methods , Animals , Cell Line , Fluorescent Dyes , Magnetic Resonance Imaging , Mice , Microscopy, Electron , NIH 3T3 Cells , Neutron Activation Analysis , Rhodamines , Tomography, X-Ray Computed
8.
Bioorg Med Chem Lett ; 15(24): 5558-61, 2005 Dec 15.
Article in English | MEDLINE | ID: mdl-16236512

ABSTRACT

A family of differentially substituted poly(ethyleneglycol) building blocks has been assembled from commercially available material. Their utility is demonstrated by formation of amino acid conjugates, image contrast agents, gold nanoparticles, and functional antibody conjugates. Application in the cellular trafficking of antitumoral agent conjugates is expected.


Subject(s)
Polyethylene Glycols/chemistry , Amino Acids/chemistry , Animals , Antibodies/chemistry , Antineoplastic Agents/pharmacokinetics , Binding Sites , Biological Transport , Goats , Immunoglobulin G , Polyethylene Glycols/pharmacokinetics
10.
Biol Bull ; 204(3): 318-26, 2003 Jun.
Article in English | MEDLINE | ID: mdl-12807708

ABSTRACT

The deep-sea red crab Chaceon quinquedens is a commercially important crustacean on the Atlantic continental shelf and slope of North America. To assess genetic subdivision in C. quinquedens, we examined the nucleotide sequence of the mitochondrial 16S rDNA gene and the internal transcribed spacers (ITS) of the nuclear ribosomal repeat in samples from southern New England and the Gulf of Mexico. We compared those data to sequences from two congeners, a sympatric species from the Florida coast, C. fenneri, and an allopatric eastern Atlantic species, C. affinis. The 16S rDNA data consisted of 379 aligned nucleotides obtained from 37 individuals. The greatest genetic difference among geographical groups or nominal species was between C. quinquedens from southern New England and C. quinquedens from the Gulf of Mexico. Haplotypes from these two groups had a minimum of 10 differences. All 11 C. fenneri samples matched the most common haplotype found in C. quinquedens from the Gulf of Mexico, and this haplotype was not detected in C. quinquedens from southern New England. The three haplotypes of C. affinis were unique to that recognized species, but those haplotypes differed only slightly from those of C. fenneri and C. quinquedens from the Gulf of Mexico. Based on 16S rDNA and ITS data, genetic differences between C. quinquedens from southern New England and the Gulf of Mexico are large enough to conclude that these are different fishery stocks. Our results also indicate that the designation of morphological species within the commercially important genus Chaceon is not congruent with evolutionary history. The genetic similarity of C. affinis from the eastern Atlantic and C. quinquedens from the Gulf of Mexico suggests these trans-Atlantic taxa share a more recent common history than the two populations of "C. quinquedens" that we examined.


Subject(s)
Brachyura/genetics , Genetic Variation , Phylogeny , Animals , Atlantic Ocean , Base Sequence , Body Weights and Measures , DNA Primers , DNA, Mitochondrial/genetics , DNA, Ribosomal/genetics , Geography , Haplotypes/genetics , Molecular Sequence Data , Sequence Analysis, DNA
12.
Evolution ; 48(3): 549-563, 1994 Jun.
Article in English | MEDLINE | ID: mdl-28568250

ABSTRACT

Excirolana braziliensis is a dioecious marine isopod that lives in the high intertidal zone on both sides of tropical America. It lacks a dispersal phase and displays a remarkable degree of genetic divergence even between localities less than 1 km apart. Nine populations of this nominal species from both sides of the Isthmus of Panama and one population of the closely allied species, Excirolana chamensis, from the eastern Pacific were studied for 2 yr for allozymic temporal variation in 13 loci and for 3 to 4 yr for morphological variation in nine characters. The genetic and morphological constitution of 9 out of 10 populations remained stable. Allele frequencies at two loci and overall morphology in a tenth beach occupied by E. braziliensis changed drastically and significantly between 1986 and 1988. The change in gene frequency is too great to explain by genetic drift occurring during a maximum of 14 generations regardless of assumed effective population size; drift is also unlikely to have caused observed changes in morphology. Selective survival of a previously rare genotype is more plausible but still not probable. The most credible explanation is that the resident population at this locality became extinct and that the beach was recolonized by immigrants from another locality. Such infrequent episodes of extinction and recolonization from a single source may account for the large amount of genetic divergence between local populations of E. braziliensis. However, the low probability of large temporal genetic change even in a species such as this, in which gene flow between local demes is limited and generation time is short, suggests that a single sample through time is usually adequate for reconstructing the genetic history of populations.

13.
Evolution ; 48(3): 530-548, 1994 Jun.
Article in English | MEDLINE | ID: mdl-28568259

ABSTRACT

Excirolana braziliensis is a dioecious marine isopod that lives in the high intertidal zone of sandy beaches on both sides of Central and South America. It possesses no larval stage and has only limited means of adult dispersal. Indirect estimates of gene flow have indicated that populations from each beach exchange less than one propagule per generation. Multivariate morphometrics have discovered three morphs of this species in Panama, two of them closely related and found on opposite sides of Central America ("C morph" in the Caribbean and "C' morph" in the eastern Pacific), the third found predominantly in the eastern Pacific ("P morph"). Though the P and C' morphs are seldom found on the same beach, they have overlapping latitudinal ranges in the eastern Pacific. A related species, Excirolana chamensis, has been described from the Pacific coast of Panama. Each beach contains populations that remain morphologically and genetically stable, but a single drastic change in both isozymes and morphology has been documented. We studied isozymes and multivariate morphology of 10 populations of E. braziliensis and of one population of E. chamensis. Our objective was to assess the degree of genetic and morphological variation, the correlation of divergence on these two levels of integration, the phylogenetic relationships between morphs, and the possible contributions of low vagility, low gene flow, and occasional extinction and recolonization to the genetic structuring of populations. Genetic distance between the P morph, on one hand, and the other two morphotypes of E. braziliensis, on the other, was as high as the distance between E. braziliensis and E. chamensis. Several lines of evidence agree that E. chamensis and the P morph had diverged from other morphs of E. braziliensis before the rise of the Panama Isthmus separated the C and C' forms, and that the P morph constitutes a different species. A high degree of genetic differentiation also exists between populations of the same morph. On the isozyme level, every population can be differentiated from every other on the basis of at least one diagnostically different locus, regardless of geographical distance or morphological affiliation. Morphological and genetic distances between populations are highly correlated. However, despite the high degree of local variation, evolution of E. braziliensis as a whole has not been particularly rapid; divergence between the C and C' morphs isolated for 3 million yr by the Isthmus of Panama is not high by the standard of within-morph differentiation or by comparison with other organisms similarly separated. Alleles that are common in one population may be absent from another of the same morph, yet they appear in a different morph in a separate ocean. The high degree of local differentiation, the exclusive occupation of a beach by one genotype with rare arrival of foreign individuals that cannot interbreed freely with the residents, the genetic stability of populations with infrequent complete replacement by another genetic population, and the sharing by morphs of polymorphisms that are not shared by local populations, all suggest a mode of evolution concentrated in rare episodes of extinction and recolonization, possibly coupled with exceptional events of gene flow that help preserve ancestral variability in both oceans.

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