23 research outputs found
Immune response and production perfomance in piglets vaccinated at 15 and 21 days old against circovirus infection
A global experiment on motivating social distancing during the COVID-19 pandemic
Finding communication strategies that effectively motivate social distancing continues to be a global public health priority during the COVID-19 pandemic. This cross-country, preregistered experiment (n = 25,718 from 89 countries) tested hypotheses concerning generalizable positive and negative outcomes of social distancing messages that promoted personal agency and reflective choices (i.e., an autonomy-supportive message) or were restrictive and shaming (i.e., a controlling message) compared with no message at all. Results partially supported experimental hypotheses in that the controlling message increased controlled motivation (a poorly internalized form of motivation relying on shame, guilt, and fear of social consequences) relative to no message. On the other hand, the autonomy-supportive message lowered feelings of defiance compared with the controlling message, but the controlling message did not differ from receiving no message at all. Unexpectedly, messages did not influence autonomous motivation (a highly internalized form of motivation relying on one’s core values) or behavioral intentions. Results supported hypothesized associations between people’s existing autonomous and controlled motivations and self-reported behavioral intentions to engage in social distancing. Controlled motivation was associated with more defiance and less long-term behavioral intention to engage in social distancing, whereas autonomous motivation was associated with less defiance and more short- and long-term intentions to social distance. Overall, this work highlights the potential harm of using shaming and pressuring language in public health communication, with implications for the current and future global health challenges
A global experiment on motivating social distancing during the COVID-19 pandemic
Significance
Communicating in ways that motivate engagement in social distancing remains a critical global public health priority during the COVID-19 pandemic. This study tested motivational qualities of messages about social distancing (those that promoted choice and agency vs. those that were forceful and shaming) in 25,718 people in 89 countries. The autonomy-supportive message decreased feelings of defying social distancing recommendations relative to the controlling message, and the controlling message increased controlled motivation, a less effective form of motivation, relative to no message. Message type did not impact intentions to socially distance, but people’s existing motivations were related to intentions. Findings were generalizable across a geographically diverse sample and may inform public health communication strategies in this and future global health emergencies.
Abstract
Finding communication strategies that effectively motivate social distancing continues to be a global public health priority during the COVID-19 pandemic. This cross-country, preregistered experiment (n = 25,718 from 89 countries) tested hypotheses concerning generalizable positive and negative outcomes of social distancing messages that promoted personal agency and reflective choices (i.e., an autonomy-supportive message) or were restrictive and shaming (i.e., a controlling message) compared with no message at all. Results partially supported experimental hypotheses in that the controlling message increased controlled motivation (a poorly internalized form of motivation relying on shame, guilt, and fear of social consequences) relative to no message. On the other hand, the autonomy-supportive message lowered feelings of defiance compared with the controlling message, but the controlling message did not differ from receiving no message at all. Unexpectedly, messages did not influence autonomous motivation (a highly internalized form of motivation relying on one’s core values) or behavioral intentions. Results supported hypothesized associations between people’s existing autonomous and controlled motivations and self-reported behavioral intentions to engage in social distancing. Controlled motivation was associated with more defiance and less long-term behavioral intention to engage in social distancing, whereas autonomous motivation was associated with less defiance and more short- and long-term intentions to social distance. Overall, this work highlights the potential harm of using shaming and pressuring language in public health communication, with implications for the current and future global health challenges
A global experiment on motivating social distancing during the COVID-19 pandemic
Finding communication strategies that effectively motivate social distancing continues to be a global public health priority during the COVID-19 pandemic. This cross-country, preregistered experiment (n = 25,718 from 89 countries) tested hypotheses concerning generalizable positive and negative outcomes of social distancing messages that promoted personal agency and reflective choices (i.e., an autonomy-supportive message) or were restrictive and shaming (i.e. a controlling message) compared to no message at all. Results partially supported experimental hypotheses in that the controlling message increased controlled motivation (a poorly-internalized form of motivation relying on shame, guilt, and fear of social consequences) relative to no message. On the other hand, the autonomy-supportive message lowered feelings of defiance compared to the controlling message, but the controlling message did not differ from receiving no message at all. Unexpectedly, messages did not influence autonomous motivation (a highly-internalized form of motivation relying on one’s core values) or behavioral intentions. Results supported hypothesized associations between people’s existing autonomous and controlled motivations and self-reported behavioral intentions to engage in social distancing: Controlled motivation was associated with more defiance and less long-term behavioral intentions to engage in social distancing, whereas autonomous motivation was associated with less defiance and more short- and long-term intentions to social distance. Overall, this work highlights the potential harm of using shaming and pressuring language in public health communication, with implications for the current and future global health challenges
The first record of <i>mcr-1</i> gene for colistin resistance in pigs from Serbia: should we be worried?
Colistin is being used as a last-resort drug to treat infections caused by multidrug-resistant (MDR) bacteria in humans. In veterinary medicine, colistin has been used for the treatment and prevention of infectious diseases. In the first study of mcr genes by multiplex PCR in healthy pigs from Serbia, we discovered mcr-1 in 4.85% out of 350 fecal samples. The presence of mcr-1 gene was detected on three farms located less than 100 km apart from each other, predominantly in piglet samples. The results point to the necessity of monitoring of colistin resistance and the mcr genes in food producing animals as well as restricting colistin usage on farms
Electrocatalysis by nanoparticles - Oxygen reduction on Ebonex/Pt electrode
The oxygen reduction reaction was studied in 0.5 mol dm-3 HClO4 solution on an electrode based on Ebonex-supported platinum electrocatalyst applied on rotation Au disk electrode (Au/Ebonex/Pt). Pt catalyst was prepared by impregnation method from 2-propanol solution of Pt(NH3)2(NO2)2 and Ebonex powder. Ebonex support (non-stoichiometric mixture of titanium oxides) was characterized by: X-ray diffraction, energy dispersive X-ray spectroscopy and BET techniques. The synthesized catalyst was analysed by TEM technique. The kinetics of oxygen reduction reaction on the Ebonex/Pt catalyst shows a significant enhancement in comparison with the same on polycrystalline Pt. Only a single Tafel slope of -0.106 V dec-1 is observed and the first-rate determining step in direct four-electron reduction is proposed as a main partway in the whole range of potential. The absence of PtOH layer, that inhibits oxygen reduction on polycrystalline Pt, was discussed through synergetic effect into the catalyst as a consequence of the interactions of Pt nanoparticles with Ebonex, on one hand, and, through the d-band coupling model where the surface reactivity is given by the energy shift of the surface d-states with respect to the Fermi level, on the other hand
Electrocatalytic activity of nano-sized Ebonex/Pt for underpotential deposition of hydrogen
The underpotential deposition of hydrogen was studied in 0.5 mol dm(-3) HClO4 solution on an electrode based on Ebonex-supported platinum electrocatalyst spread on rotation Au disk electrode (Ebonex/Pt). Pt catalyst was prepared by the impregnation method from 2-propanol solution of Pt(NH3)(2)(NO2)(2) and Ebonex powder. Ebonex support (nonstoichiometric mixture of titanium oxides) was characterized by: X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDX) and BET techniques. The synthesized catalyst was analyzed by TEM technique. Voltammetric profiles at the Ebonex/Pt catalyst surface in 0.5 mol dm(-3) HClO4 aqueous solution obtained at different temperatures with the evaluation of the temperature effect on the reversible adsorption of the H-upd state are presented and the thermodynamic state functions for H adatom adsorption process are calculated. The chemisorptive energy strength of the Ebonex/Pt-H state is estimated in order to establish the relationship between the surface structure and the electrocatalytic activity of Ebonex/Pt electrode and compare it to the one for smooth polycrystalline Pt
Characterization of a surface modified carbon cryogel and a carbon supported Pt catalyst
A carbon cryogel, synthesized by carbonization of a resorcinol/formaldehyde cryogel and oxidized in nitric acid, was used as catalyst support for Pt nano-particles. The Pt/C catalyst was prepared by a modified polyol synthesis method in an ethylene glycol (EG) solution. Characterization by nitrogen adsorption showed that the carbon cryogel support and the Pt/C catalyst were mesoporous materials with high specific surface areas (SBET > 400 m2 g-1) and large mesoporous volumes. X-Ray diffraction of the catalyst demonstrated the successful reduction of the Pt precursor to metallic form. TEM Images of the Pt/C catalyst and Pt particle size distribution showed that the mean Pt particle size was about 3.3 nm. Cyclic voltammetry (CV) experiments at various scan rates (from 2 to 200 mV s-1) were performed in 0.5 mol dm-3 HClO4 solution. The large capacitance of the oxidized carbon cryogel electrode, which arises from a combination of the double-layer capacitance and pseudocapacitance, associated with the participation of surface redox-type reactions was demonstrated. For the oxidized carbon cryogel, the total specific capacitance determined by 1/C vs. ν0.5 extrapolation method was found to be 386 F g-1. The hydrogen oxidation reaction at the investigated Pt/C catalyst proceeded as an electrochemically reversible, two-electron direct discharge reaction
Temperaturna zavisnost elektrohemijske redukcije kiseonika na nanočesticama platine na ugljeničnom nosaču
The temperature dependence of oxygen reduction reaction (ORR) was studied on highly dispersed Pt nanoparticles supported on a carbon cryo-gel. The specific surface area of the support was 517 m2 g-1, the Pt particles diameter was about 2.7 nm and the loading of the catalyst was 20 wt.%. The kinetics of the ORR at the Pt/C electrode was examined in 0.50 mol dm-3 HClO4 solution in the temperature range from 274 to 318 K. At all temperatures, two distinct E-log j regions were observed; at low current densities with a slope of -2.3RT/F and at high current densities with a slope of -2.3´2RT/F. In order to confirm the mechanism of oxygen reduction previously suggested at a polycrystalline Pt and a Pt/Ebonex nanostructured electrode, the apparent enthalpies of activation at selected potentials vs. the reversible hydrogen electrode were calculated in both current density regions. Although ∆H ≠a,1 gt ∆H ≠a,h , it was a,1 a, h found that the enthalpies of activation at the zero Galvani potential difference were the same and hence it could be concluded that the rate-determining step of the ORR was the same in both current density regions. The synthesized Pt/C catalyst showed a small enhancement in the catalytic activity for ORR in comparison to the polycrystalline Pt, but no change in the mechanism of the reaction.Kinetika reakcije redukcije kiseonika je ispitivana na nanočesticama platine dispergovanim na ugljeničnom nosaču, u 0,50 mol dm-3 HClO4, u temperaturnom intervalu od 278 do 318 K. Za sintezu Pt katalizatora (Pt/C) je primenjena modifikovana poliol metoda iz rastvora etilen glikola, dok je kao nosač korišćen ugljenični kriogel. Katalizator je okarakterisan primenom BET metode, difrakcije X-zraka (XRD) i transmisione elektronske mikroskopije (TEM). Kinetika reakcije redukcije kiseonika ispitivana je korišćenjem stacionarne polarizacione metode i metode ciklične voltametrije. Oblast malih gustina struje, na svim teperaturama, na krivoj polarizacije, karakteriše vrednost Tafelovog nagiba od -2.3RT/F, dok je u oblasti visokih gustina struje vrednost ovog nagiba -2.3x2RT/F. Određene su vrednosti prividne entalpije aktivacije na konstantnim potencijalima, za obe oblasti gustina struja, i njihova razlika iskazana za nulu Galvanijeve razlike potencijala. Potvrđeno je da je mehanizam redukcije kiseonika, kao i stupanj koji određuje ukupnu brzinu reakcije isti u obe oblasti gustina struja, a da je razlika u kinetici reakcije posledica razlike u zavisnosti adsorpcije reakcionih intermedijara od potencijala. Poređenjem katalitičke aktivnosti, izražene preko gustine struje po realnoj površini katalizatora, konstatovana je nešto veća aktivnost Pt/C katalizatora u odnosu na polikristalnu Pt
Pt/C doped by MoOx as the electrocatalyst for oxygen reduction and methanol oxidation
The oxidation of methanol and reduction of oxygen were studied on MoOx-Pt/C nano-catalysts prepared by the polyole method combined by MoOx post-deposition. The catalysts were characterized by TEM and EDX. The presented composition of the electrode is very similar to the nominal ones and post-deposited MoOx species block only a small fraction of the active Pt particle surface area. MoOx deposition on the carbon support can be ruled out from the EDX results and the low mobility of these oxides at corresponding conditions. The electrode catalytic activity in the electrooxidation of methanol and the reduction of oxygen was studied by steady-state voltammetry and cyclic voltammetry. MoOx-Pt/C catalyst exhibits higher catalytic activity than Pt/C for the oxygen reduction. The catalytic effect in oxidation of methanol is achieved only under potentiodynamic conditions, when poisoning species have no enough time to develop fully