784 research outputs found

    Radiative decays of mesons in the NJL model

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    We revisit the theoretical predictions for anomalous radiative decays of pseudoscalar and vector mesons. Our analysis is performed in the framework of the Nambu-Jona-Lasinio model, introducing adequate parameters to account for the breakdown of chiral symmetry. The results are comparable with those obtained in previous approaches.Comment: 19 pages incl. 4 figure

    The Ideal Mixing Departure in Vector Meson Physics

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    In this work we study the departure for the ideal ϕ−ω\phi-\omega mixing angle in the frame of the Nambu-Jona-Lasinio model. We have shown that in that context, the flavour symmetry breaking is unable to produce the shifting in the mixing angle. We introduce a nonet symmetry breaking in the neutral vector sector to regulate the non-strange content of the ϕ\phi meson. The phenomenon is well reproduced by our proposal.Comment: 12 pages incl. 1 figur

    First-order phase transition from hypernuclear matter to deconfined quark matter obeying new constraints from compact star observations

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    We reconsider the problem of the hyperon puzzle and its suggested solution by quark deconfinement within the two-phase approach to hybrid compact stars with recently obtained hadronic and quark matter equations of state. For the hadronic phase we employ the hypernuclear equation of state from the lowest order constrained variational method and the quark matter phase is described by a sufficiently stiff equation of state based on a color superconducting nonlocal Nambu-Jona-Lasinio model with constant (model nlNJLA) and with density-dependent (model nlNJLB) parameters. We study the model dependence of the phase transition obtained by a Maxwell construction. Our study confirms that also with the present set of equations of state quark deconfinement presents a viable solution of the hyperon puzzle even for the new constraint on the lower limit of the maximum mass from PSR J0740+6620. In this work we provide with model nlNJLB for the first time a hybrid star EoS with an intermediate hypernuclear matter phase between the nuclear and color superconducting quark matter phases, for which the maximum mass of the compact star reaches 2.2 M⊙2.2~M_\odot, in accordance with most recent constraints. In model nlNJLA such a phase cannot be realised because the phase transition onset is at low densities, before the hyperon threshold density is passed. We discuss possible consequences of the hybrid equation of state for the deconfinement phase transition in symmetric matter as it will be probed in future heavy-ion collisions at FAIR, NICA and corresponding energy scan programs at the CERN and RHIC facilities.Comment: 37 pages, 13 figures, 1 table, references added, text and figures revised, version accepted for publication in Phys. Rev.

    Bayesian analysis of multimessenger M-R data with interpolated hybrid EoS

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    We introduce a family of equations of state (EoS)for hybrid neutron star (NS) matter that is obtained by atwo-zone parabolic interpolation between a soft hadronicEoS at low densities and a set of stiff quark matter EoSat high densities within a finite region of chemical potentialsμH < μ < μQ. Fixing the hadronic EoS as the APRone and choosing the color-superconducting, nonlocal NJLmodel with two free parameters for the quark phase, we performBayesian analyses with this two-parameter family ofhybrid EoS. Using three different sets of observational constraintsthat include the mass of PSR J0740+6620, the tidaldeformability for GW170817, and the mass-radius relationfor PSR J0030+0451 from NICER as obligatory (set 1), whileset 2 uses the possible upper limit on themaximummass fromGW170817 as an additional constraint and set 3 instead ofthe possibility that the lighter object in the asymmetric binarymerger GW190814 is a neutron star. We confirm that in anycase, the quark matter phase has to be color superconductingwith the dimensionless diquark coupling approximately fulfillingthe Fierz relation ηD = 0.75 and the most probablesolutions exhibiting a proportionality between ηD and ηV , thecoupling of the repulsive vector interaction that is requiredfor a sufficiently largemaximummass.We used theBayesiananalysis to investigate with the method of fictitious measureaments the consequences of anticipating different radii for themassive 2 M PSR J0740+6220 for the most likely equationof state. With the actual outcome of the NICER radius measurementon PSR J0740+6220 we could conclude that for themost likely hybrid star EoS would not support a maximummass as large as 2.5 M so that the event GW190814 was abinary black hole merger.Fil: Ayriyan, Alexander. Laboratory of Information Technologies; Rusia. A. Alikhanyan National Laboratory; Armenia. Dubna State University; RusiaFil: Blaschke, David. University of Wroclaw; Polonia. Bogoliubov Laboratory for Theoretical Physics; Rusia. National Research Nuclear University; RusiaFil: Grunfeld, Ana Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Comisión Nacional de Energía Atómica; ArgentinaFil: Alvarez Castillo, D. E.. Bogoliubov Laboratory for Theoretical Physics; Rusia. Henryk Niewodniczanski Institute of Nuclear Physics; PoloniaFil: Grigorian, H.. A. Alikhanyan National Laboratory; Armenia. Yerevan State University; Armenia. Laboratory of Information Technologies; RusiaFil: Abgaryan, V.. Laboratory of Information Technologies; Rusia. A. Alikhanyan National Laboratory; Armenia. Peoples’ Friendship University of Russia; Rusi

    Interventions for raising breast cancer awareness in women

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    Background: Breast cancer continues to be the most commonly diagnosed cancer in women globally. Early detection, diagnosis and treatment of breast cancer are key to better outcomes. Since many women will discover a breast cancer symptom themselves, it is important that they are breast cancer aware i.e. have the knowledge, skills and confidence to detect breast changes and present promptly to a healthcare professional.Objectives: To assess the effectiveness of interventions for raising breast cancer awareness in women.Search methods: We searched the Cochrane Breast Cancer Group's Specialised Register (searched 25 January 2016), Cochrane Central Register of Controlled Trials (CENTRAL; 2015, Issue 12) in the Cochrane Library (searched 27 January 2016), MEDLINE OvidSP (2008 to 27 January 2016), Embase (Embase.com, 2008 to 27 January 2016), the World Health Organization’s International Clinical Trials Registry Platform (ICTRP) search portal and ClinicalTrials.gov (searched 27 Feburary 2016). We also searched the reference lists of identified articles and reviews and the grey literature for conference proceedings and published abstracts. No language restriction was applied.Selection criteriaRandomised controlled trials (RCTs) focusing on interventions for raising women’s breast cancer awareness i.e. knowledge of potential breast cancer symptoms/changes and the confidence to look at and feel their breasts, using any means of delivery, i.e. one-to-one/group/mass media campaign(s).Data collection and analysis: Two authors selected studies, independently extracted data and assessed risk of bias. We reported the odds ratio (OR) and 95% confidence intervals (CIs) for dichotomous outcomes and mean difference (MD) and standard deviation (SD) for continuous outcomes. Since it was not possible to combine data from included studies due to their heterogeneity, we present a narrative synthesis. We assessed the quality of evidence using GRADE methods.Main results: We included two RCTs involving 997 women: one RCT (867 women) randomised women to receive either a written booklet and usual care (intervention group 1), a written booklet and usual care plus a verbal interaction with a radiographer or research psychologist (intervention group 2) or usual care (control group); and the second RCT (130 women) randomised women to either an educational programme (three sessions of 60 to 90 minutes) or no intervention (control group).Knowledge of breast cancer symptoms: In the first study, knowledge of non-lump symptoms increased in intervention group 1 compared to the control group at two years postintervention, but not significantly (OR 1.1, 95% CI 0.7 to 1.6; P = 0.66; 449 women; moderate-quality evidence). Similarly, at two years postintervention, knowledge of symptoms increased in the intervention group 2 compared to the control group but not significantly (OR 1.4, 95% CI 0.9 to 2.1; P = 0.11; 434 women; moderate-quality evidence). In the second study, women’s awareness of breast cancer symptoms had increased one month post intervention in the educational group (MD 3.45, SD 5.11; 65 women; low-quality evidence) compared to the control group (MD −0.68, SD 5.93; 65 women; P &lt; 0.001), where there was a decrease in awareness.Knowledge of age-related risk: In the first study, women’s knowledge of age-related risk of breast cancer increased, but not significantly, in intervention group 1 compared to control at two years postintervention (OR 1.8; 95% CI 0.9 to 3.5; P &lt; 0.08; 447 women; moderate-quality evidence). Women's knowledge of risk increased significantly in intervention group 2 compared to control at two years postintervention (OR 4.8, 95% CI 2.6 to 9.0; P &lt; 0.001; 431 women; moderate-quality evidence). In the second study, women’s perceived susceptibility (how at risk they considered themselves) to breast cancer had increased significantly one month post intervention in the educational group (MD 1.31, SD 3.57; 65 women; low-quality evidence) compared to the control group (MD −0.55, SD 3.31; 65 women; P = 0.005), where a decrease in perceived susceptibility was noted.Frequency of Breast Checking: In the first study, no significant change was noted for intervention group 1 compared to control at two years postintervention (OR 1.1, 95% CI 0.8 to 1.6; P = 0.54; 457 women; moderate-quality evidence). Monthly breast checking increased, but not significantly, in intervention group 2 compared to control at two years postintervention (OR 1.3, 95% CI 0.9 to 1.9; P = 0.14; 445 women; moderate-quality evidence). In the second study, women’s breast cancer preventive behaviours increased significantly one month post intervention in the educational group (MD 1.21, SD 2.54; 65 women; low-quality evidence) compared to the control group (MD 0.15, SD 2.94; 65 women; P &lt; 0.045).Breast Cancer Awareness: Women’s overall breast cancer awareness did not change in intervention group 1 compared to control at two years postintervention (OR 1.8, 95% CI 0.6 to 5.30; P = 0.32; 435 women; moderate-quality evidence) while overall awareness increased in the intervention group 2 compared to control at two years postintervention (OR 8.1, 95% CI 2.7 to 25.0; P &lt; 0.001; 420 women; moderate-quality evidence). In the second study, there was a significant increase in scores on the Health Belief Model (that included the constructs of awareness and perceived susceptibility) at one month postintervention in the educational group (mean 1.21, SD 2.54; 65 women) compared to the control group (mean 0.15, SD 2.94; 65 women; P = 0.045).Neither study reported outcomes relating to motivation to check their breasts, confidence to seek help, time from breast symptom discovery to presentation to a healthcare professional, intentions to seek help, quality of life, adverse effects of the interventions, stages of breast cancer, survival estimates or breast cancer mortality rates.Authors' conclusions: Based on the results of two RCTs, a brief intervention has the potential to increase women’s breast cancer awareness. However, findings of this review should be interpreted with caution, as GRADE assessment identified moderate-quality evidence in only one of the two studies reviewed. In addition, the included trials were heterogeneous in terms of the interventions, population studied and outcomes measured. Therefore, current evidence cannot be generalised to the wider context. Further studies including larger samples, validated outcome measures and longitudinal approaches are warranted

    Reduction of circulating cholesterol and apolipoprotein levels during sepsis

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    Sepsis with multiple organ failure is frequently associated with a substantial decrease of cholesterol levels. This decrease of cholesterol is strongly associated with mortality suggesting a direct relation between inflammatory conditions and altered cholesterol homeostasis. The host response during sepsis is mediated by cytokines and growth factors, which are capable of influencing lipid metabolism. Conversely lipoproteins are also capable of modulating cytokine production during the inflammatory response. Therefore the decrease in circulating cholesterol levels seems to play a crucial role in the pathophysiology of sepsis. In this review the interaction between cytokines and lipid metabolism and its clinical consequences will be discussed

    The views of older women towards mammographic screening: a qualitative and quantitative study

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    Purpose: Mammographic screening has improved breast cancer survival in the screened age group. This improved survival has not been seen in older women (>70 years) where screening uptake is low. This study explores the views, knowledge and attitudes of older women towards screening. Methods: Women (>70) were interviewed about breast screening. Interview findings informed the development of a questionnaire which was sent to 1000 women (>70) to quantify their views regarding screening. Results: Twenty-six women were interviewed and a questionnaire designed. The questionnaire response rate was 48.3% (479/992). Over half (52.9%, 241/456) of respondents were unaware they could request mammography by voluntary self-referral and were unaware of how to arrange this. Most (81.5% 383/470) had not attended breast screening since turning 70. Most (75.6%, 343/454) felt screening was beneficial and would attend if invited. Most, (90.1%, 412/457) felt screening should be offered to all women regardless of age or health. Conclusions: There is a lack of knowledge about screening in older women. The majority felt that invitation to screening should be extended to the older age group regardless of age or health. The current under-utilised system of voluntary self referral is not supported by older women

    Options for early breast cancer follow-up in primary and secondary care : a systematic review

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    Background Both incidence of breast cancer and survival have increased in recent years and there is a need to review follow up strategies. This study aims to assess the evidence for benefits of follow-up in different settings for women who have had treatment for early breast cancer. Method A systematic review to identify key criteria for follow up and then address research questions. Key criteria were: 1) Risk of second breast cancer over time - incidence compared to general population. 2) Incidence and method of detection of local recurrence and second ipsi and contra-lateral breast cancer. 3) Level 1–4 evidence of the benefits of hospital or alternative setting follow-up for survival and well-being. Data sources to identify criteria were MEDLINE, EMBASE, AMED, CINAHL, PSYCHINFO, ZETOC, Health Management Information Consortium, Science Direct. For the systematic review to address research questions searches were performed using MEDLINE (2011). Studies included were population studies using cancer registry data for incidence of new cancers, cohort studies with long term follow up for recurrence and detection of new primaries and RCTs not restricted to special populations for trials of alternative follow up and lifestyle interventions. Results Women who have had breast cancer have an increased risk of a second primary breast cancer for at least 20 years compared to the general population. Mammographically detected local recurrences or those detected by women themselves gave better survival than those detected by clinical examination. Follow up in alternative settings to the specialist clinic is acceptable to women but trials are underpowered for survival. Conclusions Long term support, surveillance mammography and fast access to medical treatment at point of need may be better than hospital based surveillance limited to five years but further large, randomised controlled trials are needed
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