623 research outputs found
The Heider balance - a continuous approach
The Heider balance (HB) is investigated in a fully connected graph of
nodes. The links are described by a real symmetric array r(i,j), i,j=1,...,N.
In a social group, nodes represent group members and links represent relations
between them, positive (friendly) or negative (hostile). At the balanced state,
r(i,j)r(j,k)r(k,i)>0 for all the triads (i,j,k). As follows from the structure
theorem of Cartwright and Harary, at this state the group is divided into two
subgroups, with friendly internal relations and hostile relations between the
subgroups. Here the system dynamics is proposed to be determined by a set of
differential equations. The form of equations guarantees that once HB is
reached, it persists. Also, for N=3 the dynamics reproduces properly the
tendency of the system to the balanced state. The equations are solved
numerically. Initially, r(i,j) are random numbers distributed around zero with
a symmetric uniform distribution of unit width. Calculations up to N=500 show
that HB is always reached. Time to get the balanced state varies with the
system size N as N^{-1/2}. The spectrum of relations, initially narrow, gets
very wide near HB. This means that the relations are strongly polarized. In our
calculations, the relations are limited to a given range around zero. With this
limitation, our results can be helpful in an interpretation of somestatistical
data.Comment: 9 pages, 4 figures. Int. J. Mod. Phys. C (2005), in prin
The effect of intergroup contact on solidarity-based collective action is mediated by reductions in SDO
This paper explores the impact of positive and negative intergroup contact on advantaged group members’ willingness to engage in collective action on behalf of disadvantaged outgroups, and the meditational role of social dominance orientation (SDO) in this process. SDO captures an individuals’ ideological support for inequality. If contact is going to promote collective action to reduce inequality amongst the advantaged group, it must be expected to influence their ideological beliefs about hierarchy. In Study 1 only positive, and not negative contact was found to be associated with Whites’ support for the Black Lives Matter movement, mediated by reductions in SDO. In Study 2, both positive and negative contact were associated respectively, with more or less support for collective action to protect the rights of European immigrants during Brexit negotiations. While positive contact was associated with reduced SDO and more support for collective action amongst British nationals, negative contact was associated with increased SDO and lower support for collective action
Insulin resistance and insulin secretory dysfunction are independent predictors of worsening of glucose tolerance during each stage of type 2 diabetes development
WSTĘP. Chociaż wyniki prospektywnych prac wskazują, że zaburzenia działania i wydzielania insuliny zapowiadają wystąpienie cukrzycy typu 2, jednakże nie dostarczają one dostatecznych informacji o współudziale tych dwóch czynników w pogarszaniu tolerancji glukozy w różnych okresach rozwoju cukrzycy typu 2. Dlatego autorzy podjęli próbę niezależnej oceny wpływu zaburzeń wydzielania i działania insuliny na przejście od stanu prawidłowej tolerancji glukozy (NGT, normal glucose tolerance) do tolerancji nieprawidłowej (IGT, impaired glucose tolerance) i ze stanu IGT w cukrzycę.
MATERIAŁ I METODY. U 254 Indian Pima z NGT i u 145 z IGT autorzy badali stymulowane insuliną usuwanie glukozy (M) (klamra hiperinsulinowa), wielkość wydzielania insuliny w fazie wczesnej (AIR, acute insulin secretory response) (25-gramowy dożylny test tolerancji glukozy) i zawartość składników ciała (hydrodensytometria lub ilościowa radiografia cyfrowa). Czas obserwacji tych osób wynosił 0,5–13 lat.
WYNIKI. Po okresie obserwacji 4,4 ± 3,1 i 5,5 ± 3,4 lat u 79 (31%) osób, u których początkowo występowała NGT, rozwinęła się IGT, a u 64 (44%) osób z początkową IGT rozwinęła się cukrzyca. Analiza statystyczna przeprowadzona z uwzględnieniem wieku, płci i zawartości procentowej tłuszczu wskazała na niskie M i niskie AIR jako niezależne czynniki określające ryzyko przejścia od NGT do IGT (względne ryzyko [95% CI] dla 10. vs 90. percentyla: M 2,4 [1,2–4,7], p < 0,02; AIR 2,1 [1,1–4,1], p < 0,04), a dla przejścia IGT w cukrzycę (M 2,5 [1,3–5,0], p < 0,01; AIR 1,8 [0,99–3,3], p = 0,055).
WNIOSKI. Zarówno zaburzenia w działaniu, jak i upośledzenie wydzielania insuliny są niezależnymi czynnikami zapowiadającymi pogorszenie tolerancji glukozy na każdym etapie rozwoju cukrzycy i oba powinny stanowić cel prewencji pierwotnej cukrzycy typu 2.OBJECTIVE. Although prospective studies indicate
that insulin resistance and insulin secretory dysfunction
predict type 2 diabetes, they provide limited
information on the relative contributions of both
abnormalities to worsening glucose tolerance at different
developmental stages of the disease. We therefore
assessed the predictive effect of insulin resistance
and insulin secretory dysfunction separately
for the progression from normal glucose tolerance
(NGT) to impaired glucose tolerance (IGT) and from
IGT to diabetes.
RESEARCH DESIGN AND METHODS. Insulin-stimulated
glucose disposal (M) (hyperinsulinemic clamp),
acute insulin secretory response (AIR) (25-g intravenous
glucose tolerance test), and body composition
(hydrodensitometry or dual-energy X-ray absorptiometry)
were measured in 254 Pima Indians with NGT
and in 145 Pima Indians with IGT, who were then
followed for 0.5–13 years.
RESULTS. After follow-ups of 4.4 ± 3.1 and 5.5 ± 3.4
years, 79 (31%) of the subjects with initial NGT had
developed IGT, and 64 (44%) of the subjects with initial
IGT had developed diabetes. In proportional-hazards
analyses with adjustment for age, sex, and percent
body fat, low M and low AIR were independent
predictors of both the progression from NGT to IGT
(relative hazards [95% CI] for 10th vs. 90th percentile:
M2.4 [1.2–4.7], P < 0.02; AIR 2.1 [1.1–4.1], P < 0.04)
and from IGT to diabetes (M2.5 [1.3–5.0], P < 0.01;
AIR 1.8 [0.99–3.3], P = 0.055).
CONCLUSIONS. During each stage of the development
of type 2 diabetes, insulin resistance and insulin secretory
dysfunction are independent predictors of
worsening glucose tolerance and are, therefore, both
targets for the primary prevention of the disease
Perceiving Mixed Valence Emotions Reduces Intergroup Dehumanization
To deny others’ humanity is one of the most heinous forms of intergroup prejudice. Given evidence that perceiving various forms of complexity in outgroup members reduces intergroup prejudice, we investigated across three experiments whether the novel dimension of emotional complexity, or outgroup members’ joint experience of mixed-valence emotions, would also reduce their dehumanization. Experiment 1 found that perceiving fictitious aliens’ experience of the same primary emotions (e.g., sadness) presented in mixed vs. non-mixed valence pairs led to reduced prejudice via attenuated dehumanization, i.e. attribution of uniquely human emotions. Experiment 2 confirmed these results, using an unfamiliar real-world group as an outgroup target. Experiment 3 used a familiar outgroup and found generally similar effects, reducing social distance through reduced dehumanization. These processes suggest that an alternate route to reduced dehumanizing of outgroups might involve presenting mixed valence emotions
Social Network Evolution during Long-term Migration: A comparison of three case studies in the South Wales region
Ten years after Poland joined the European Union (EU), a sizable number of the once considered short-term migrants that entered the United Kingdom (UK) post-2004 have remained. From the literature, it is known that when initially migrating, social networks, composed of family and friends, are used to facilitate migration. Later, migrants’ social networks may evolve to include local, non-ethnic members of the community. Through these networks, migrants may access new opportunities within the local economy. They also serve to socialise newcomers in the cultural modalities of life in the destination country. However, what if migrants’ social networks do not evolve or evolve in a limited manner? Is cultural integration still possible under these conditions? Using data collected from three case studies in the South Wales region –Cardiff, Merthyr Tydfil & Llanelli- from 2008-2012, the aim of this article is to compare Polish migrants’ social network usage, or lack thereof, over time. This comparison will be used to understand how these social networks can be catalysts and barriers for cultural integration. The findings point to the migrants’ varied use of their local social networks, which is dependent upon their language skill acquisition and their labour market mobility in the destination country
Use of an electronic administrative database to identify older community dwelling adults at high-risk for hospitalization or emergency department visits: The elders risk assessment index
<p>Abstract</p> <p>Background</p> <p>The prevention of recurrent hospitalizations in the frail elderly requires the implementation of high-intensity interventions such as case management. In order to be practically and financially sustainable, these programs require a method of identifying those patients most at risk for hospitalization, and therefore most likely to benefit from an intervention. The goal of this study is to demonstrate the use of an electronic medical record to create an administrative index which is able to risk-stratify this heterogeneous population.</p> <p>Methods</p> <p>We conducted a retrospective cohort study at a single tertiary care facility in Rochester, Minnesota. Patients included all 12,650 community-dwelling adults age 60 and older assigned to a primary care internal medicine provider on January 1, 2005. Patient risk factors over the previous two years, including demographic characteristics, comorbid diseases, and hospitalizations, were evaluated for significance in a logistic regression model. The primary outcome was the total number of emergency room visits and hospitalizations in the subsequent two years. Risk factors were assigned a score based on their regression coefficient estimate and a total risk score created. This score was evaluated for sensitivity and specificity.</p> <p>Results</p> <p>The final model had an AUC of 0.678 for the primary outcome. Patients in the highest 10% of the risk group had a relative risk of 9.5 for either hospitalization or emergency room visits, and a relative risk of 13.3 for hospitalization in the subsequent two year period.</p> <p>Conclusions</p> <p>It is possible to create a screening tool which identifies an elderly population at high risk for hospital and emergency room admission using clinical and administrative data readily available within an electronic medical record.</p
Heroes against homophobia: Does elevation uniquely block homophobia by inhibiting disgust?
Homophobia has decreased in past decades, but gut-level disgust towards gay men lingers. It has been suggested that disgust can be reduced by inducing its proposed opposite emotion, elevation. Elevation is elicited by witnessing self-sacrifice and other uncommon acts of moral goodness. Research suggests elevation might reduce homophobia, but only general elevation (not elevation specifically evoked by gay people) and general attitudes (rather than disgust) have been studied. Nor has elevation’s proposed specific effect on homophobia been differentiated from effects of related emotions, such as admiration or surprise. A series of news stories featuring either a gay man or a man of unspecified sexuality that were intended to elicit elevation, admiration, or surprise distinctly were pretested. We pre-registered the prediction that an elevation-inducing story would reduce negative attitudes by reducing disgust. In Study 1 (N = 593), participants who read elevation-inducing stories did not express more positive attitudes or less disgust towards gay men than those who read stories inducing admiration or surprise. The admiration stories elicited similar or lower levels of disgust than the elevation stories. Study 2 (N = 588), replicated the findings of Study 1 with improved stimuli and measures. Both studies suggest that elevation may not uniquely reduce homophobia, as elevation and admiration have similar effects on this prejudice
Human plasma and serum extracellular small RNA reference profiles and their clinical utility
Circulating extracellular RNAs (exRNAs) have the potential to serve as biomarkers for a wide range of medical conditions. However, limitations in existing exRNA isolation methods and a lack of knowledge on parameters affecting exRNA variability in human samples may hinder their successful discovery and clinical implementation. Using combinations of denaturants, reducing agents, proteolysis, and revised organic extraction, we developed an automated, high-throughput approach for recovery of exRNAs and exDNA from the same biofluid sample. We applied this method to characterize exRNAs from 312 plasma and serum samples collected from 13 healthy volunteers at 12 time points over a 2-month period. Small RNA cDNA library sequencing identified nearly twofold increased epithelial-, muscle-, and neuroendocrine-cell–specific miRNAs in females, while fasting and hormonal cycle showed little effect. External standardization helped to detect quantitative differences in erythrocyte and platelet-specific miRNA contributions and in miRNA concentrations between biofluids. It also helped to identify a study participant with a unique exRNA phenotype featuring a miRNA signature of up to 20-fold elevated endocrine-cell–specific miRNAs and twofold elevated total miRNA concentrations stable for over 1 year. Collectively, these results demonstrate an efficient and quantitative method to discern exRNA phenotypes and suggest that plasma and serum RNA profiles are stable over months and can be routinely monitored in long-term clinical studies
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