Analysis of a risk based model for the growth of AIDS infection

Several models for the spread of AIDS within a homosexual community have been proposed that incorporate biased mixing of different risk groups. A simple model is presented that captures many of the features of these more complex models. Analytical expressions are derived for the time to the state of maximum infection (SMI) in a particular risk group, the proportion infected at SMI, and the number of infected individuals as the group approaches SMI. These results agree qualitatively with numerical simulations of the model

What Good Is Good-morning? (There\u27s More Good In Good-night !)

With Ukulele arrangement. Contains advertisements and/or short musical examples of pieces being sold by publisher.https://digitalcommons.library.umaine.edu/mmb-vp/6995/thumbnail.jp

Epigenetic regulation of Dlg1, via Kaiso, alters mitotic spindle polarity and promotes intestinal tumourigenesis

Both alterations to the epigenome and loss of polarity have been linked to cancer initiation, progression and metastasis. It has previously been demonstrated that loss of the epigenetic reader protein Kaiso suppresses intestinal tumourigenesis in the Apc+/min mouse model, in which altered polarity plays a key role. Thus, we investigated the link between Kaiso deficiency, polarity and suppression of intestinal tumourigenesis. We used Kaiso deficient mice to conditionally delete Apc within the intestinal epithelia and demonstrated up-regulation of the spindle polarity genes Dlg1 and Dlgap1. To understand the role of Dlg1 we generated Villin-creApc+/minDlg1flx/flx Kaiso-/y mice to analyse gene expression, survival, tumour burden and spindle orientation. In vivo analysis of the Dlg1 deficient intestine revealed improper orientation of mitotic spindles and a decreased rate of cellular migration. Loss of Dlg1 decreased survival in Apc+/min mice, validating its role as a tumour suppressor in the intestine. Significantly the increased survival of Apc+/minKaisoy/- mice was shown to be dependent on Dlg1 expression. Taken together this data indicates that maintenance of spindle polarity in the intestinal crypt requires appropriate regulation of Dlg1 expression. As Dlg1 loss leads to incorrect spindle orientation and a delay in cells transiting the intestinal crypt. We propose that the delayed exit from the crypt increases the window in which spontaneous mutations can become fixed, producing a 'tumour-permissive' environment, without an increase in mutation rate. Implications: Loss of mitotic spindle polarity delays the exit of cells from the intestinal crypt and promotes a tumourigenic environment

Bourgeois ambivalence: a comparative investigation of Thomas Mann’s Der Zauberberg and T. S. Eliot’s The Waste Land

The thesis explores important similarities and differences between responses to bourgeois society in Thomas Mann’s Der Zauberberg (1924) and T. S. Eliot’s The Waste Land (1922). It examines these texts’ presentations of the shifting morality of bourgeois culture, the prevailing sense of paralysis and fragmentation at the beginning of the twentieth century, and compares the authors’ use of allusions to myth, and their explorations of concepts of time. However, by considering the ambivalent responses to bourgeois society as they are presented within these texts, and a selection of Mann and Eliot’s other creative and critical works, the thesis also highlights significant differences in the authors’ responses to bourgeois society, which are indicative of the broader divergent traditions in which they positioned themselves. Eliot subscribes to a tradition based upon the framework of the Christian faith, and the classical literary canon, with an ‘impersonal’ approach to artistic creation. By contrast, Mann places the German ‘burgher’ at the core of the tradition to which he subscribes, emphasising personality, and favouring a humanistic approach, which values the individual’s capacity for ethical judgement based on reason. This framework demonstrates that the thematic similarities and common allusions in Mann and Eliot’s creative works are underscored by radically different authorial approaches and belief systems

The roles of segmental and tandem gene duplication in the evolution of large gene families in Arabidopsis thaliana

BACKGROUND: Most genes in Arabidopsis thaliana are members of gene families. How do the members of gene families arise, and how are gene family copy numbers maintained? Some gene families may evolve primarily through tandem duplication and high rates of birth and death in clusters, and others through infrequent polyploidy or large-scale segmental duplications and subsequent losses. RESULTS: Our approach to understanding the mechanisms of gene family evolution was to construct phylogenies for 50 large gene families in Arabidopsis thaliana, identify large internal segmental duplications in Arabidopsis, map gene duplications onto the segmental duplications, and use this information to identify which nodes in each phylogeny arose due to segmental or tandem duplication. Examples of six gene families exemplifying characteristic modes are described. Distributions of gene family sizes and patterns of duplication by genomic distance are also described in order to characterize patterns of local duplication and copy number for large gene families. Both gene family size and duplication by distance closely follow power-law distributions. CONCLUSIONS: Combining information about genomic segmental duplications, gene family phylogenies, and gene positions provides a method to evaluate contributions of tandem duplication and segmental genome duplication in the generation and maintenance of gene families. These differences appear to correspond meaningfully to differences in functional roles of the members of the gene families

Measurement of alcohol craving

Despite considerable research activity and application in treatment, the construct of craving remains poorly understood. We propose that cravings and urges are cognitive-emotional events in time, characterised by frequency, duration, intensity and salience. Commonly used measures of alcohol craving are reviewed, and their strengths and weaknesses identified. Most measures confound craving with behaviors, or with separable cognitive phenomena such as expectancies, intentions, or perceived behavioral control. These confounds have limited our advances in understanding the determinants and consequences of craving. Based on the criteria applied in this review, among the better performing multi-item measures are the Penn Alcohol Craving Scale and Obsessive subscale of the Obsessive-Compulsive Drinking Scale. Optimal assessment strategies are likely to involve daily assessments of peak intensity of cravings, desires or urges and of the frequency and duration of craving episodes. Of particular interest are measures of intensity at times when individuals are at risk of drinking or of other functional impacts from craving

Utilitarian Collective Choice and Voting

In his seminal Social Choice and Individual Values, Kenneth Arrow stated that his theory applies to voting. Many voting theorists have been convinced that, on account of Arrow’s theorem, all voting methods must be seriously flawed. Arrow’s theory is strictly ordinal, the cardinal aggregation of preferences being explicitly rejected. In this paper I point out that all voting methods are cardinal and therefore outside the reach of Arrow’s result. Parallel to Arrow’s ordinal approach, there evolved a consistent cardinal theory of collective choice. This theory, most prominently associated with the work of Harsanyi, continued the older utilitarian tradition in a more formal style. The purpose of this paper is to show that various derivations of utilitarian SWFs can also be used to derive utilitarian voting (UV). By this I mean a voting rule that allows the voter to score each alternative in accordance with a given scale. UV-k indicates a scale with k distinct values. The general theory leaves k to be determined on pragmatic grounds. A (1,0) scale gives approval voting. I prefer the scale (1,0,-1) and refer to the resulting voting rule as evaluative voting. A conclusion of the paper is that the defects of conventional voting methods result not from Arrow’s theorem, but rather from restrictions imposed on voters’ expression of their preferences. The analysis is extended to strategic voting, utilizing a novel set of assumptions regarding voter behavior

Acting out when psychosocial safety climate is low: understanding why middle-level managers experience upward mistreatment

IntroductionUpward mistreatment, despite being under studied, is an influential phenomenon affecting middle managers’ well-being and performance. The work environment hypothesis of bullying proposes that an undesirable work context is the main cause of workplace bullying, suggesting the importance of creating an anti-mistreatment climate, that is, psychosocial safety climate (PSC). In this study, we argue that upward bullying and aggression are unsafe behaviors, a “retaliation” by employees resulting from their unsafe work context.MethodsUsing a large-scale multisource sample collected from 123 organizations, 6,658 middle managers and 34,953 employees, we examined the relationship between collective PSC, individual-perceived PSC and middle managers’ experience of upward mistreatment.ResultsSingle-level and multi-level modeling results suggested that PSC is an important element in reducing the likelihood of upward bullying and aggression, in turn, protecting managers’ well-being. More importantly, upward bullying is a way that employees act out when there is an undesirable working context.DiscussionFuture research on workplace mistreatment should examine PSC and upward mistreatment. Interventions provided should focus on improving PSC which could in turn preventing upward mistreatment, thereby improving psychosocial safety for both employees and middle managers to prevent negative actions