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Laboratory capture, isolation and analysis of microparticles in aerogel: Preparation for the return of Stardust
We present observations from the laboratory capture of particles in aerogel. The paper focuses on a possible extraction technique and the bulk mineral characterization of the captured material using non-destructive analytical techniques
Gravitational Baryogenesis
We show that a gravitational interaction between the derivative of the Ricci
scalar curvature and the baryon-number current dynamically breaks CPT in an
expanding universe and, combined with baryon-number-violating interactions, can
drive the universe towards an equilibrium baryon asymmetry that is
observationally acceptable.Comment: Revtex4, 4 pages, two figure
High stakes lies: Police and non-police accuracy in detecting deception
This is an Accepted Manuscript of an article published by Taylor & Francis in Psychology, Crime and Law on 26 June 2014 available online: http://wwww.tandfonline.com/10.1080/1068316X.2014.935777To date, the majority of investigations in to accuracy in detecting deception have used low stakes lies as stimulus materials, and findings from these studies suggest that people are generally poor at detecting deception. The research presented here utilised real life, high stakes lies as stimulus materials, to investigate the accuracy of police and non-police observers in detecting deception. It was hypothesised that both police and non-police observers would achieve above chance levels of accuracy in detecting deception, that police officers would be more accurate at detecting deception than non-police observers, that confidence in veracity judgements would be positively related to accuracy, and that consensus judgements would predict veracity. 107 observers (70 police officers and 37 non-police participants) watched 36 videos of people lying or telling the truth in an extremely high stakes, real life situation. Police observers achieved mean accuracy in detecting deception of 72%, non-police observers achieved 68% mean accuracy, and confidence in veracity judgements were positively related to accuracy. Consensus judgements correctly predicted veracity in 92% of cases.ESRC grant number ES/I013288/
Cost-Effectiveness of Skin Surveillance Through a Specialized Clinic for Patients at High Risk of Melanoma
Purpose
Clinical guidelines recommend that people at high risk of melanoma receive regular surveillance to
improve survival through early detection. A specialized High Risk Clinic in Sydney, Australia was
found to be effective for this purpose; however, wider implementation of this clinical service requires evidence of cost-effectiveness and data addressing potential overtreatment of suspicious
skin lesions.
Patients and Methods
A decision-analytic model was built to compare the costs and benefits of specialized surveillance
compared with standard care over a 10-year period, from a health system perspective. A high-risk
standard care cohort was obtained using linked population data, comprising the Sax Institute’s 45
and Up cohort study, linked to Medicare Benefits Schedule claims data, the cancer registry, and
hospital admissions data. Benefits were measured in quality-adjusted life-years gained. Sensitivity
analyses were undertaken for all model parameters.
Results
Specialized surveillance through the High Risk Clinic was both less expensive and more effective
than standard care. The mean saving was A5,564 to $8,092) per patient, and the
mean quality-adjusted life-year gain was 0.31 (95% CI, 0.27 to 0.35). The main drivers of the differences were detection of melanoma at an earlier stage resulting in less extensive treatment and
a lower annual mean excision rate for suspicious lesions in specialized surveillance (0.81; 95% CI,
0.72 to 0.91) compared with standard care (2.55; 95% CI, 2.34 to 2.76). The results were robust
when tested in sensitivity analyses.
Conclusion
Specialized surveillance was a cost-effective strategy for the management of individuals at high risk
of melanoma. There were also fewer invasive procedures in specialized surveillance compared with
standard care in the community
Improving subjective perception of personal cancer risk: systematic review and meta-analysis of educational interventions for people with cancer or at high risk of cancer
BACKGROUND: Newly diagnosed patients with cancer require education about the disease, the available treatments and potential consequences of treatment. Greater understanding of cancer risk has been found to be associated with greater health-related quality of life, improved psychological adjustment and greater health-related behaviours. The aim of this sytematic review was to assess the effectiveness of educational interventions in improving subjective cancer risk perception and to appraise the quality of the studies. METHODS: We conducted a systematic review and meta-analysis of randomised controlled trials (RCTs) and prospective observational studies. Eligible studies were identified via Medline, PsycINFO, AMED, CINAHL and Embase databases. After screening titles and abstracts, two reviewers independently assessed the eligibility of 206 full-text articles. RESULTS: Forty papers were included in the review; the majority of studies were conducted among breast cancer patients (n = 29) and evaluated the effect of genetic counselling on personal perceived risk (n = 25). Pooled results from RCTs (n = 12) showed that, both in the short and long term, educational interventions did not significantly influence risk perception level (standardised mean difference 0.05, 95% CI -0.24-0.34; p = 0.74) or accuracy (odds ratio = 1.96, 95% CI: 0.61-6.25; p = 0.26). Only one RCT reported a short-term difference in risk ratings (p = 0.01). Of prospective observational studies (n = 28), many did demonstrate changes in the level of perceived risk and improved risk accuracy and risk ratings in both the short and long term. However, only one (of three) observational studies reported a short-term difference in risk ratings (p < = 0.003). CONCLUSION: Further development and investigation of educational interventions using good quality, RCTs are warranted
SU(3) family symmetry and neutrino bi-tri-maximal mixing
The observed large mixing angles in the lepton sector may be the first signal
for the presence of a non-Abelian family symmetry. However, to obtain the
significant differences between the mixing of the neutrino and charged fermion
sectors, the vacuum expectation values involved in the breaking of such a
symmetry in the two sectors must be misaligned. We investigate how this can be
achieved in models with an SU(3) family symmetry consistent with an underlying
GUT. We show that such misalignment can be achieved naturally via the see-saw
mechanism. We construct a specific example in which the vacuum (mis)alignment
is guaranteed by additional symmetries. This model generates a fermion mass
structure consistent with all quark and lepton masses and mixing angles.
Neutrino mixing is close to bi-tri-maximal mixing.Comment: References added; typos correcte
Non-Existence of Black Holes in Certain Spacetimes
Assuming certain asymptotic conditions, we prove a general theorem on the
non-existence of static regular (i.e., nondegenerate) black holes in spacetimes
with a negative cosmological constant, given that the fundamental group of
space is infinite. We use this to rule out the existence of regular negative
mass AdS black holes with Ricci flat scri. For any mass, we also rule out a
class of conformally compactifiable static black holes whose conformal infinity
has positive scalar curvature and infinite fundamental group, subject to our
asymptotic conditions. In a limited, but important, special case our result
adds new support to the AdS/CFT inspired positive mass conjecture of Horowitz
and Myers.Comment: 17 pages, Latex. Typos corrected, minor changes to the text. Accepted
for publication in Classical and Quantum Gravit
Effects of vessel traffic on relative abundance and behaviour of cetaceans : the case of the bottlenose dolphins in the Archipelago de La Maddalena, north-western Mediterranean sea
Acknowledgements This study was part of the Tursiops Project of the Dolphin Research Centre of Caprera, La Maddalena. Financial and logistical support was provided by the Centro Turistico Studentesco (CTS) and by the National Park of the Archipelago de La Maddalena. We thank the Natural Reserve of Bocche di Bonifacio for the support provided during data collection. The authors thank the numerous volunteers of the Caprera Dolphin Research Centre and especially Marco Ferraro, Mirko Ugo, Angela Pira and Maurizio Piras whose assistance during field observation and skills as a boat driver were invaluable.Peer reviewedPostprin
Explaining global surface aerosol number concentrations in terms of primary emissions and particle formation
We use observations of total particle number concentration at 36 worldwide sites and a global aerosol model to quantify the primary and secondary sources of particle number. We show that emissions of primary particles can reasonably reproduce the spatial pattern of observed condensation nuclei (CN) (R2=0.51) but fail to explain the observed seasonal cycle at many sites (R2=0.1). The modeled CN concentration in the free troposphere is biased low (normalised mean bias, NMB=−88%) unless a secondary source of particles is included, for example from binary homogeneous nucleation of sulfuric acid and water (NMB=−25%). Simulated CN concentrations in the continental boundary layer (BL) are also biased low (NMB=−74%) unless the number emission of anthropogenic primary particles is increased or an empirical BL particle formation mechanism based on sulfuric acid is used. We find that the seasonal CN cycle observed at continental BL sites is better simulated by including a BL particle formation mechanism (R2=0.3) than by increasing the number emission from primary anthropogenic sources (R2=0.18). Using sensitivity tests we derive optimum rate coefficients for this nucleation mechanism, which agree with values derived from detailed case studies at individual sites
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