217 research outputs found

    Communicating risk under high uncertainty: developing cross-disciplinary knowledge

    Get PDF
    The primary purpose of this Special Issue is to coalesce different perspectives on the theme of ‘Communicating Risk Under High Uncertainty’ from across a range of subject areas. These areas include environmental studies, international relations, engineering, sociology, psychology, media studies, the health sciences, criminology and anthropology. By bringing different perspectives together, we anticipate that commonalities and points of concurrence will help to identify cross-disciplinary synergies and provide opportunities to explore the potential for a more holistic understanding of risk communication in the academy and beyond

    Wavelet phase evaluation extended to digital speckle patterninterferometry

    Get PDF
    A wavelet algorithm developed to improve metrology based on electronic speckle pattern intérferometry (ESPI) is presented. The wavelet algorithm is based on the calculation of the continuous wavelet transform of a modulated speckle correlation fringes .The Paul wavelet is used , the extraction of the maximum scales of the modulus of the wavelet transform leads simply to the phase gradient distribution. The advantage of the method is to provide phase distribution, with a high accuracy, from a single interferogram without unwrapping step.A wavelet algorithm developed to improve metrology based on electronic speckle pattern intérferometry (ESPI) is presented. The wavelet algorithm is based on the calculation of the continuous wavelet transform of a modulated speckle correlation fringes .The Paul wavelet is used , the extraction of the maximum scales of the modulus of the wavelet transform leads simply to the phase gradient distribution. The advantage of the method is to provide phase distribution, with a high accuracy, from a single interferogram without unwrapping step

    Channeling Effects in Direct Dark Matter Detectors

    Full text link
    The channeling of the ion recoiling after a collision with a WIMP changes the ionization signal in direct detection experiments, producing a larger signal than otherwise expected. We give estimates of the fraction of channeled recoiling ions in NaI (Tl), Si and Ge crystals using analytic models produced since the 1960's and 70's to describe channeling and blocking effects. We find that the channeling fraction of recoiling lattice nuclei is smaller than that of ions that are injected into the crystal and that it is strongly temperature dependent.Comment: 8 pages, 12 figures, To appear in the Proceedings of the sixth International Workshop on the Dark Side of the Universe (DSU2010) Leon, Guanajuato, Mexico 1-6 June 201

    Template-Directed Ligation of Peptides to Oligonucleotides

    Get PDF
    Synthetic oligonucleotides and peptides have enjoyed a wide range of applications in both biology and chemistry. As a consequence, oligonucleotide-peptide conjugates have received considerable attention, most notably in the development of antisense constructs with improved pharmacological properties. In addition, oligonucleotide-peptide conjugates have been used as molecular tags, in the assembly of supramolecular arrays and in the construction of encoded combinatorial libraries. To make these chimeric molecules more accessible for a broad range of investigations, we sought to develop a facile method for joining fully deprotected oligonucleotides and peptides through a stable amide bond linkage. Furthermore, we wished to make this ligation reaction addressable, enabling one to direct the ligation of specific oligonucleotide and peptide components.To confer specificity and accelerate the rate of the reaction, the ligation process was designed to be dependent on the presence of a complementary oligonucleotide template

    Daily modulation due to channeling in direct dark matter crystalline detectors

    Full text link
    The channeling of the ion recoiling after a collision with a WIMP in direct dark matter crystalline detectors produces a larger scintillation or ionization signal than otherwise expected. Channeling is a directional effect which depends on the velocity distribution of WIMPs in the dark halo of our Galaxy and could lead to a daily modulation of the signal. Here we compute upper bounds to the expected amplitude of daily modulation due to channeling using channeling fractions that we obtained with analytic models in prior work. After developing the general formalism, we examine the possibility of finding a daily modulation due to channeling in the data already collected by the DAMA/NaI and DAMA/LIBRA experiments. We find that even the largest daily modulation amplitudes (of the order of 10% in some instances) would not be observable for WIMPs in the standard halo in the 13 years of data taken by the DAMA collaboration. For these to be observable the DAMA total rate should be 1/40 of what it is or the total DAMA exposure should be 40 times larger. The daily modulation due to channeling will be difficult to measure in future experiments. We find it could be observed for light WIMPs in solid Ne, assuming no background.Comment: 29 pages, 15 figures. v3: version accepted by PRD. Minor corrections made, corrected Eq. 12 and 13 and Figs. 2, 3.a, and 4.a, corrected Eqs. 27-38 by a factor of 2, added the observability condition for solid N

    Siting of HIV/AIDS diagnostic equipment in South Africa: a case study in locational analysis

    No full text
    This paper describes a practical application of locational analysis to the siting of HIV/AIDS diagnostic equipment in laboratories across South Africa. Classical location analytical techniques were extended to ensure that laboratories are sited as close as possible to major centres of demand from hospitals and clinics. A particular advantage of the modified set covering algorithm developed is that choices between laboratory sites are made in a transparent manner. In order to find appropriate numbers and ideal placement of CD4 laboratories, runs were undertaken for various scenarios based on maximum travel time from health facilities to laboratory sites. Results demonstrated to decision makers showed close comparisons with pilot review projects undertaken in four health districts of South Africa. The research has potential to impact health care delivery to HIV sufferers in the poorest rural regions of the country

    Properties of Contextual Memory Formed in the Absence of αCaMKII Autophosphorylation

    Get PDF
    The alpha-isoform of calcium/calmodulin-dependent kinase II (αCaMKII) is a major synaptic kinase that undergoes autophosphorylation after NMDA receptor activation, switching the kinase into a calcium-independent activity state. This αCaMKII autophosphorylation is essential for NMDA receptor-dependent long-term potentiation (LTP), induced by a single tetanus, in hippocampal area CA1 and in neocortex. Furthermore, the αCaMKII autophosphorylation is essential for contextual long-term memory (LTM) formation after a single training trial but not after a massed training session. Here, we show that in the absence of αCaMKII autophosphorylation contextual fear conditioning is hippocampus dependent and that multi-tetanus-dependent late-LTP cannot be induced in hippocampal area CA1. Furthermore, we show that in the absence of αCaMKII autophosphorylation contextual LTM persists for 30 days, the latest time point tested. Additionally, contextual, but not cued, LTM formation in the absence of αCaMKII autophosphorylation appears to be impaired in 18 month-old mice. Taken together, our findings suggest that αCaMKII autophosphorylation-independent plasticity in the hippocampus is sufficient for contextual LTM formation and that αCaMKII autophosphorylation may be important for delaying age-related impairments in hippocampal memory formation. Furthermore, they propose that NMDA receptor-dependent LTP in hippocampal area CA1 is essential for contextual LTM formation after a single trial but not after massed training. Finally, our results challenge the proposal that NMDA receptor-dependent LTP in neocortex is required for remote contextual LTM

    Risk of first and recurrent stroke in childhood cancer survivors treated with cranial and cervical radiation therapy.

    Get PDF
    PurposeTo assess, in a retrospective cohort study, rates and predictors of first and recurrent stroke in patients treated with cranial irradiation (CRT) and/or cervical irradiation at ≤18 years of age.Methods and materialsWe performed chart abstraction (n=383) and phone interviews (n=104) to measure first and recurrent stroke in 383 patients who received CRT and/or cervical radiation at a single institution between 1980 and 2009. Stroke was defined as a physician diagnosis and symptoms consistent with stroke. Incidence of first stroke was number of first strokes per person-years of observation after radiation. We used survival analysis techniques to determine cumulative incidence of first and recurrent stroke.ResultsAmong 325 subjects with sufficient follow-up data, we identified 19 first strokes (13 ischemic, 4 hemorrhagic, 2 unknown subtype) occurring at a median age of 24 years (interquartile range 17-33 years) in patients treated with CRT. Imaging was reviewed when available (n=13), and the stroke was confirmed in 12. Overall rate of first stroke was 625 (95% confidence interval [CI] 378-977) per 100,000 person-years. The cumulative incidence of first stroke was 2% (95% CI 0.01%-5.3%) at 5 years and 4% (95% CI 2.0%-8.4%) at 10 years after irradiation. With each 100-cGy increase in the radiation dose, the stroke hazard increased by 5% (hazard ratio 1.05; 95% CI 1.01-1.09; P=.02). We identified 6 recurrent strokes; 5 had available imaging that confirmed the stroke. Median time to recurrence was 15 months (interquartile range 6 months-3.2 years) after first stroke. The cumulative incidence of recurrent stroke was 38% (95% CI 17%-69%) at 5 years and 59% (95% CI 27%-92%) at 10 years after first stroke.ConclusionCranial irradiation puts childhood cancer survivors at high risk of both first and recurrent stroke. Stroke prevention strategies for these survivors are needed

    Comparative Effectiveness of mRNA-1273 and BNT162b2 COVID-19 Vaccines Among Older Adults: Systematic Literature Review and Meta-Analysis Using the GRADE Framework

    Get PDF
    INTRODUCTION:The mRNA vaccines mRNA-1273 and BNT162b2 demonstrated high efficacy against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in phase 3 clinical trials, including among older adults. To inform coronavirus disease 2019 (COVID-19) vaccine selection, this systematic literature review (SLR) and meta-analysis assessed the comparative effectiveness of mRNA-1273 versus BNT162b2 in older adults. METHODS: We systematically searched for relevant studies reporting COVID-19 outcomes with mRNA vaccines in older adults aged ≥ 50 years by first cross-checking relevant published SLRs. Based on the cutoff date from a previous similar SLR, we then searched the WHO COVID-19 Research Database for relevant articles published between April 9, 2022, and June 2, 2023. Outcomes of interest were SARS-CoV-2 infection, symptomatic SARS-CoV-2 infection, severe SARS-CoV-2 infection, COVID-19–related hospitalization, and COVID-19–related death following ≥ 2 vaccine doses. Random effects meta-analysis models were used to pool risk ratios (RRs) across studies. Heterogeneity was evaluated using chi-square testing. Evidence certainty was assessed per GRADE framework. RESULTS:Twenty-four non-randomized real-world studies reporting clinical outcomes with mRNA vaccines in individuals aged ≥ 50 years were included in the meta-analysis. Vaccination with mRNA-1273 was associated with significantly lower risk of SARS-CoV-2 infection (RR 0.72 [95% confidence interval (CI) 0.64‒0.80]), symptomatic SARS-CoV-2 infection (RR 0.72 [95% CI 0.62‒0.83]), severe SARS-CoV-2 infection (RR 0.67 [95% CI 0.57‒0.78]), and COVID-19–related hospitalization (RR 0.65 [95% CI 0.53‒0.79]) but not COVID-19–related death (RR 0.80 [95% CI 0.64‒1.00]) compared with BNT162b2. There was considerable heterogeneity between studies for all outcomes (I2 > 75%) except death (I2 = 0%). Multiple subgroup and sensitivity analyses excluding specific studies generally demonstrated consistent results. Certainty of evidence across outcomes was rated as low (type 3) or very low (type 4), reflecting the lack of randomized controlled trial data. CONCLUSI0N: Meta-analysis of 24 observational studies demonstrated significantly lower risk of asymptomatic, symptomatic, and severe infections and hospitalizations with the mRNA-1273 versus BNT162b2 vaccine in older adults aged ≥ 50 years

    Constitutive Overexpression of Muscarinic Receptors Leads to Vagal Hyperreactivity

    Get PDF
    BACKGROUND: Alterations in muscarinic receptor expression and acetylcholinesterase (AchE) activity have been observed in tissues from Sudden Infant Death Syndrome (SIDS). Vagal overactivity has been proposed as a possible cause of SIDS as well as of vasovagal syncopes. The aim of the present study was to seek whether muscarinic receptor overexpression may be the underlying mechanism of vagal hyperreactivity. Rabbits with marked vagal pauses following injection of phenylephrine were selected and crossed to obtain a vagal hyperreactive strain. The density of cardiac muscarinic receptors and acetylcholinesterase (AchE) gene expression were assessed. Blood markers of the observed cardiac abnormalities were also sought. METHODOLOGY/PRINCIPAL FINDINGS: Cardiac muscarinic M(2) and M(3) receptors were overexpressed in hyperreactive rabbits compared to control animals (2.3-fold and 2.5-fold, respectively) and the severity of the phenylephrine-induced bradycardia was correlated with their densities. A similar overexpression of M(2) receptors was observed in peripheral mononuclear white blood cells, suggesting that cardiac M(2) receptor expression can be inferred with high confidence from measurements in blood cells. Sequencing of the coding fragment of the M(2) receptor gene revealed a single nucleotide mutation in 83% of hyperreactive animals, possibly contributing for the transcript overexpression. Significant increases in AchE expression and activity were also assessed (AchE mRNA amplification ratio of 3.6 versus normal rabbits). This phenomenon might represent a compensatory consequence of muscarinic receptors overexpression. Alterations in M(2) receptor and AchE expression occurred between the 5th and the 7th week of age, a critical period also characterized by a higher mortality rate of hyperreactive rabbits (52% in H rabbits versus 13% in normal rabbits) and preceeded the appearance of functional disorders. CONCLUSIONS/SIGNIFICANCE: The results suggest that cardiac muscarinic receptor overexpression plays a critical role in the development of vagal hyperreactivity, whereas AchE hyperactivity appears as a compensatory consequence of it. Since similar vagal disorders were observed recently by us in SIDS, muscarinic receptor overexpression could become a marker of risk of vasovagal syncopes and SIDS
    corecore