6,891 research outputs found

    The third moment of quadratic Dirichlet L-functions

    Full text link
    We study the third moment of quadratic Dirichlet L-functions, obtaining an error term of size O(X3/4+ε)O(X^{3/4 + \varepsilon}).Comment: 27 pages. v2: modified a remark on p.

    Secondary Breast Augmentation: Managing Each Case

    Get PDF
    Breast augmentation is one of the most regularly performed interventions requiring reoperation in aesthetic surgery. For this reason, it involves a greater chance for complications. In this report, the authors aim to provide young plastic surgeons with guidelines based on their experience for responding to each of these complications, to explain the causes and ways of avoiding them, and to show how they can be treated when they occur

    Four cycles of paclitaxel and carboplatin as adjuvant treatment in early-stage ovarian cancer: a six-year experience of the Hellenic Cooperative Oncology Group

    Get PDF
    BACKGROUND: Surgery can cure a significant percentage of ovarian carcinoma confined to the pelvis. Nevertheless, there is still a 10–50% recurrence rate. We administered paclitaxel/carboplatin as adjuvant treatment in early-stage ovarian carcinoma. METHODS: Patients with stages Ia or Ib, Grade 2 or 3 and Ic to IIb (any grade) were included. Patients were treated with 4 cycles of Paclitaxel 175 mg/m(2 )and Carboplatin [area under the curve (AUC) 6 (Calvert Formula)] every 3 weeks. RESULTS: Sixty-nine patients with no residual disease following cytoreductive surgery and minimal or modified surgical staging were included in this analysis. Grade 3 or 4 neutropenia occured in 29.9% of patients, while neutropenic fever was reported in 4.5%. Neurotoxicity (all Grade 1 or 2) was reported in 50% of cases. Median follow-up was 62 months. 5-year overall survival (OS) and relapse-free survival (RFS) were: 87% (95% confidence intervals [CI]: 78–96) and 79% (95% CI: 69–89), respectively. Significantly fewer patients with stages Ic-IIb and tumor grade 2 or 3 achieved a 5-year RFS than patients with only one of these two factors (73% vs 92%, p = 0.03). CONCLUSION: Paclitaxel/Carboplatin chemotherapy is a safe and effective adjuvant treatment in early-stage ovarian carcinoma. Patients with stages Ic-IIb and tumor grade 2 or 3 may benefit from more extensive treatment

    Scintillator-based ion beam profiler for diagnosing laser-accelerated ion beams

    Get PDF
    Next generation intense, short-pulse laser facilities require new high repetition rate diagnostics for the detection of ionizing radiation. We have designed a new scintillator-based ion beam profiler capable of measuring the ion beam transverse profile for a number of discrete energy ranges. The optical response and emission characteristics of four common plastic scintillators has been investigated for a range of proton energies and fluxes. The scintillator light output (for 1 MeV > Ep < 28 MeV) was found to have a non-linear scaling with proton energy but a linear response to incident flux. Initial measurements with a prototype diagnostic have been successful, although further calibration work is required to characterize the total system response and limitations under the high flux, short pulse duration conditions of a typical high intensity laser-plasma interaction

    Callous-unemotional traits, low cortisol reactivity and physical aggression in children: findings from the Wirral Child Health and Development Study

    Get PDF
    Callous-unemotional (CU) traits are thought to confer risk for aggression via reduced amygdala responsivity to distress cues in others. Low cortisol reactivity is thought to confer risk for aggression via reduced arousal and this effect may be confined to boys. We tested the hypothesis that the association between childhood CU traits and aggression would be greatest in the absence of the inhibitory effects of cortisol reactivity, and that this effect would be sex dependent. Participants were 283 members of a stratified subsample within an epidemiological longitudinal cohort (WCHADS). Cortisol reactivity to a social stressor was assessed at 5 years. CU traits were reported by mothers at 5 years, and physical aggression by mothers and teachers at age 7. Results showed that CU traits were associated with elevated aggression at 7 years controlling for earlier aggression. There was no main effect of cortisol reactivity on regression. The association between CU traits and aggression was moderated by cortisol reactivity (p = .011) with a strong association between CU traits and aggression in the presence of low reactivity, and a small and non-significant association in the presence of high reactivity. This association was further moderated by child sex (p = .041) with the joint effect of high CU traits and low cortisol reactivity seen only in boys (p = .016). We report first evidence that a combined deficit in inhibitory processes associated with CU traits and low cortisol reactivity increases risk for childhood aggression, in a sex-dependent manner

    Assortment optimisation under a general discrete choice model: A tight analysis of revenue-ordered assortments

    Full text link
    The assortment problem in revenue management is the problem of deciding which subset of products to offer to consumers in order to maximise revenue. A simple and natural strategy is to select the best assortment out of all those that are constructed by fixing a threshold revenue π\pi and then choosing all products with revenue at least π\pi. This is known as the revenue-ordered assortments strategy. In this paper we study the approximation guarantees provided by revenue-ordered assortments when customers are rational in the following sense: the probability of selecting a specific product from the set being offered cannot increase if the set is enlarged. This rationality assumption, known as regularity, is satisfied by almost all discrete choice models considered in the revenue management and choice theory literature, and in particular by random utility models. The bounds we obtain are tight and improve on recent results in that direction, such as for the Mixed Multinomial Logit model by Rusmevichientong et al. (2014). An appealing feature of our analysis is its simplicity, as it relies only on the regularity condition. We also draw a connection between assortment optimisation and two pricing problems called unit demand envy-free pricing and Stackelberg minimum spanning tree: These problems can be restated as assortment problems under discrete choice models satisfying the regularity condition, and moreover revenue-ordered assortments correspond then to the well-studied uniform pricing heuristic. When specialised to that setting, the general bounds we establish for revenue-ordered assortments match and unify the best known results on uniform pricing.Comment: Minor changes following referees' comment

    ‘I think that’s bad' : lay normativity and perceived barriers to employment in primary teaching in the UK

    Get PDF
    This article reports the results of a small-scale study into undergraduates’ perceptions of possible barriers to obtaining employment within primary teaching in the UK. The investigation focused upon barriers related to accent and gender. The study sample was a group of final-year undergraduates on an Education Studies degree at a university in South Wales. The study employed a threepart theoretical framework, drawing upon the work of Bourdieu, Andrew Sayer’s discussion of lay normativity and Nancy Fraser’s theory of two-dimensional social justice, to analyse the students’ perceptions of (in)justice deriving from perceived barriers. Results from seven focus groups indicated the students perceived employment-related impediments from processes of misrecognition and maldistribution in primary teaching recruitment. However, the students held complex views on these issues. The majority also voiced discourses which, it could be argued, serve to further the reproduction of such processes of maldistribution and misrecognition

    Occasional errors can benefit coordination

    Get PDF
    The chances solving a problem that involves coordination between people are increased by introducing robotic players that sometimes make mistakes. This finding has implications for real-world coordination problems
    corecore