191 research outputs found

    From risk to fairness

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    Kadcyla is a drug that extends the life of breast cancer patients by an average of 6 mo. It also happens to be incredibly expensive. The United Kingdom’s National Health Service sparked controversy when it refused to provide this drug to patients, citing its low cost effectiveness. Cases like this raise the question of how societies should make distributive decisions. Should we maximize utility or should we aim to improve the lives of the least fortunate, even if doing so is costly for everyone else? The influential philosopher John Rawls tackled this dilemma by framing fair distributive decisions as a kind of gamble (1). Rawls famously argued that we should choose the kind of society we would all prefer if our choice was made from behind a “veil of ignorance” — that is, under conditions of complete uncertainty about where we would end up. He held that people should make such choices by following a risk-averse “maximin” strategy of maximizing the minimum possible outcome for themselves and others. Echoing Rawls’s theory, new research by Kameda et al. (2) links risk and fairness by showing that preferences about risk and about distribution may arise from common psychological and neural substrates

    Relaxation Dynamics of Electronically Excited C60− in o-Dichlorobenzene and Tetrahydrofuran Solution

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    The ultrafast response of singly negatively charged C60 fullerene in solution has been investigated by femtosecond pump-probe absorption spectroscopy and transient anisotropy in the visible and near-infrared region. Pump excitation within the near-infrared band demonstrates that this spectral feature can be described as avibrational progression associated with asingle electronic transition. Relaxation of the first electronically excited state occurs primarily by internal conversion with atime constant of 3ps, slightly depending on the solvents, tetrahydrofuran or o-dichlorobenzene, and also on the excitation wavelength. An excitation of the second electronically excited state around 530nm leads to an ultrafast internal conversion to the first excited state with apulse-limited time constant of less than 100fs. As aminor channel, stimulated emission in the spectral regime of 1150-1300nm was observed from the first electronically excited state both after near-infrared and visible excitation. After internal conversion to the electronic ground state, C60− dissipates its excess internal energy into the solvent on alonger timescale of 40-70ps. The transient anisotropy associated with directly populating the first excited state reveals an ultrafast component decaying within 100fs, which is attributed to ultrafast vibrational motions, conceivably arising from excited state pseudorotatio

    Intersystem Crossing Rates in Photoexcited Rose Bengal: Solvation versus Isolation

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    We compare the intersystem crossing rate, kISC, of Rose Bengal (RB) in an aqueous pH 12 solution with the corresponding relaxation rates of four different RB-derived anion and dianion species isolated in the gas phase: the doubly deprotonated dianion ([RB-2H]2–), the singly deprotonated monoanion ([RB-H]−), and the corresponding singly negatively charged sodium and cesium adducts ([RB-2H + Na]− and [RB-2H + Cs]−, respectively). Each of them was probed following photoexcitation of their first singlet excited states (S1) at or near room temperature. The solution was studied by transient absorption spectroscopy, whereas the mass-selected anions were characterized by time-resolved photoelectron spectroscopyall with ca. 50 femtosecond temporal resolution. [RB-H]− shows an S1 lifetime of ca. 80 ps; the solution ensemble, thought to consist primarily of solvated dianion chromophores, shows a similar lifetime of ca. 70 ps. By contrast, the isolated dianion, [RB-2H]2–, has a much longer lifetime. Superimposed on S1 decay attributable mainly to intersystem crossing, all four isolated anions also show some rapid oscillatory features of the transient photoelectron signal on a 4–5 ps timescale after excitation. Interestingly, an analogous phenomenon is also seen in the transient absorption measurements. We attribute it to a librational oscillation as the S1 state, initially populated in the S0 geometry, relaxes into its excited state equilibrium structure. Some implications of these observations for RB photophysics and interpretation of solution measurements are discussedalso in terms of density functional theory and time-dependent density functional theory calculations of ground and excited states

    Phase‐Dependent Long Persistent Phosphorescence in Coumarin‐Phosphine‐Based Coinage Metal Complexes

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    A coumarin functionalized aminodiphosphine has been introduced as a bidentate ligand in coinage metal chemistry. Mono-, di-, and trimetallic copper and silver complexes were synthesized with this ligand. The hybrid character of the ligand led to compounds with rich luminescence properties. These include coumarin-based blue fluorescence, observed as a sole emission in solution at room temperature, and green phosphorescence, which is efficient at low temperatures and dominates the spectra of the metal complexes. In the rigid environment of frozen solutions, the green phosphorescence shows an unusually long (for metal complexes) decay on the seconds timescale in high quantum yield. In addition, a red phosphorescence, which may be assigned to the triplet state localized in the phosphine-M3_{3}Cl2_{2} (M=Cu, Ag), is observed for the trinuclear complexes at low temperature. Neither the second-long phosphorescence nor the red emission is observed for the coumarin ligand, thus they must be a result of the coordination to coinage metal clusters. The excited states in these compounds were also investigated by femtosecond transient absorption spectroscopy and quantum chemical calculations

    Mental Contrasting With Implementation Intentions Reduces Drinking When Drinking Is Hazardous: An Online Self-Regulation Intervention

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    Introduction. Drinking alcohol has detrimental health consequences, and effective interventions to reduce hazardous drinking are needed. The self-regulation intervention of Mental Contrasting with Implementation Intentions (MCII) promotes behavior change across a variety of health behaviors. In this study, we tested if online delivery of MCII reduced hazardous drinking in people who were worried about their drinking. Method. Participants (N = 200, female = 107) were recruited online. They were randomized to learn MCII or solve simple math problems (control). Results. Immediately after the intervention, participants in the MCII condition (vs. control) reported an increased commitment to reduce drinking. After 1 month, they reported having taken action measured by the Readiness to Change drinking scale. When drinking was hazardous (Alcohol Use Disorders Identification Test ≥ 8, n = 85), participants in the MCII condition indicated a decreased number of drinking days, exp(β) = 0.47, CI (confidence interval) [−1.322, −.207], p = .02, and drinks per week, exp(β) = 0.57, CI [0.94, 5.514], p = .007, compared with the control condition. Discussion. These findings demonstrate that a brief, self-guided online intervention (Mdn = 28 minutes) can reduce drinking in people who worry about their drinking. Our findings show a higher impact in people at risk for hazardous drinking. Conclusion. MCII is scalable as an online intervention. Future studies should test the cost-effectiveness of the intervention in real-world settings

    Sex-specific innate immune selection of HIV-1 in utero is associated with increased female susceptibility to infection

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    Female children and adults typically generate more efficacious immune responses to vaccines and infections than age-matched males, but also suffer greater immunopathology and autoimmune disease. We here describe, in a cohort of>170 in utero HIV-infected infants from KwaZulu-Natal, South Africa, fetal immune sex differences resulting in a 1.5-2-fold increased female susceptibility to intrauterine HIV infection. Viruses transmitted to females have lower replicative capacity (p=0.0005) and are more type I interferon-resistant (p=0.007) than those transmitted to males. Cord blood cells from females of HIV-uninfected sex-discordant twins are more activated (p=0.01) and more susceptible to HIV infection in vitro (p=0.03). Sex differences in outcome include superior maintenance of aviraemia among males (p=0.007) that is not explained by differential antiretroviral therapy adherence. These data demonstrate sex-specific innate immune selection of HIV associated with increased female susceptibility to in utero infection and enhanced functional cure potential among infected males. Sex differences in the immune response to vaccines and infections have been well described in children and adults. Here the authors describe, in a cohort of 177 HIV-infected infants, innate immune sex differences in fetal life that increase female susceptibility to intrauterine HIV infection and increase the chances of subsequent HIV remission in infected males
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