1,875 research outputs found
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How to distinguish climate sceptics, antivaxxers, and persistent sceptics: Evidence from a multi-country survey of public attitudes
Distrust in science has been linked to scepticism over both vaccines and climate change. We analyse the results of nationally representative online surveys administered in eight key countries critical to global efforts to mitigate climate change and COVID-19 (Australia, Brazil, China, India, Japan, South Africa, the UK and US). Consistent with previous studies, we find distrust in science is an important explanatory variable for the larger majority of sceptics, those who are sceptical of one or the other issue but not both, across the countries examined. However, the association is significantly weaker among the segment of hardcore persistent sceptics who are both climate sceptics and antivaxxers, instead we find that these individuals, who fit with the typical sceptic profile, are driven by an underlying distrust of elite institutions rather than a specific distrust of scientists. Our results imply that different communications strategies are needed for different types of sceptics
Inhibition of Cholinesterases by the Oximes P2AM and Toxogonin
The reversible inhibition of electric eel acetylcholinesterase
(EC 3.1.1.7) by P2AM (2-(hydroxyimino)methyl-1-methyl-pyridinium
chloride) and Toxogonin (1,1\u27-[oxybis(methylene)] bis(4-(hydroxyimino)
methyl-pyridinium) dichloride) was studied using ac.etylthiocholine
as substrate. Two techniques were applied for
measuring acetylthiocholine hydrolysis, the conventional spectrophotometric
and the stopped-flow (at 25 °c in 100 mM phosphate
buffer pH = 7.4).
The correlation between the degree of inhibition, and acetylthiocholine
and oxime concentrations fits a theoretical model which
postulates that the substrate and the inhibitor bind to two sites on
the enzyme: the catalytic site and an allosteric, substrate-inhibition,
site. The calculated dissociation constants for the two sites
are: 0.13 and 0.76 mM for P2AM, and 0.16 and 2.0 mM for Toxogonin.
The suggested model is an alternative to the hypothesis that
two types of binding occur within the catalytic site.
Horse serum cholinesterase and bovine erythrocyte acetylcholinesterase
are also inhibited by P2AM and Toxogonin to about
the same degree as the electric eel enzyme.
Acetylthiocholine reacts with P2AM and Toxogonin; assuming
that the reaction is bimolecular the corresponding rate constants
are 13.4 and 22.4 M-1 min-
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China's road to a global scientific powerhouse
Drawing on the wider 'catching up' literature, we examine the rapid growth in Chinese spending on science and technology, which, in spite of its growing infrastructure, remains heavily reliant on foreign inputs. We examine both the economic and political drivers behind China's scientific development, making a distinction between domestic investments and international technology trade. Firms provide over two-thirds of total R&D funding, most of which has been spent on 'high-tech' sectors for export production. The fastest growing research area is in environmental sciences and energy technology. China's technology imports are shifting away from 'technologies for production', towards 'technologies for innovation', encouraged by the national development strategy on enhancing scientific research capacities. In particular, we present evidence from China's imported technology contracts. Energy is the second largest sector after manufacturing in terms of imported technology contracts
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Political Ideology and Public Views of the Energy Transition in Australia and the UK
We explore the relationship between political ideology and public attitudes towards a range of energy technologies (namely: biomass, coal, shale (or coal seam) gas, natural gas, carbon capture and storage, hydroelectricity, nuclear, solar thermal and photovoltaic, wave and wind energy). Our empirical analysis draws on the results of two similar nationally representative public surveys that were conducted in Australia and the UK in 2017. Our findings suggest that political ideology is significantly associated with public attitudes towards energy technologies. Specifically, supporters of left-leaning political parties tend to be more supportive of renewables and opposed to biomass, shale (coal seam) gas, nuclear and fossil fuel energies compared to right-leaning individuals. We also create an alternative ideological proxy to capture the relative emphasis that parties place on the environment and economy and find that supporters of environmentally focused parties generally express similar energy preferences to left-leaning individuals and economy-focused respondents align with right-leaning attitudes. Our findings are robust to different choices of proxy
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A comparison of public preferences for different low-carbon energy technologies: Support for CCS, nuclear and wind energy in the United Kingdom
Using a representative national survey in the United Kingdom, we investigated public attitudes towards different low-carbon technologies (carbon capture and storage (CCS), wind and nuclear power) and the factors influencing public support. Overall, we found that respondents were far more likely to support wind energy as their preferred means of mitigating climate change. Older people and those of a higher social grade are more supportive of nuclear power, while age and social grade do not significantly affect support for wind energy. Supporters of the Conservative Party were more likely to oppose wind power. Neither attitudes towards climate change nor environmental attitudes were found to influence public support for wind power or nuclear. Trust in information from environmental groups was associated with greater support for wind energy but lower support for nuclear power. Perceived cost and objective knowledge significantly influenced public support for all three technology types, that is, higher perceived costs and the poorer objective knowledge lead to lower public support. However, self-assessed knowledge did not influence public support. Many factors, including most of the tested demographic factors, did not affect support for any of the three technologies
Refinement of primary Si in hypereutectic Al-Si alloys by intensive melt shearing
Hypereutectic Al-Si based alloys are gaining popularity for applications where a combination of light weight and high wear resistance is required. The high wear resistance arising from the hard primary Si particles comes at the price of extremely poor machine tool life. To minimize machining problems while exploiting outstanding wear resistance, the primary Si particles must be controlled to a uniform small size and uniform spatial distribution. The current industrial means of refining primary Si chemically by the addition of phosphorous suffers from a number of problems. In the present paper an alternative, physical means of refining primary Si by intensive shearing of the melt prior to casting is investigated. Al-15wt%Si alloy has been solidified under varying casting conditions (cooling rate) and the resulting microstructures have been studied using microscopy and quantitative image analysis. Primary Si particles were finer, more compact in shape and more numerous with increasing cooling rate. Intensive melt shearing led to greater refinement and more enhanced nucleation of primary Si than was achieved by adding phosphorous. The mechanism of enhanced nucleation is discussed.EPSRC (grant EP/H026177/1)
The effects of combined magnesium and zinc supplementation on metabolic status in patients with type 2 diabetes mellitus and coronary heart disease
Background: The present research aimed to analyze the impacts of magnesium and zinc supplements on glycemic control, serum lipids, and biomarkers of oxidative stress and inflammation in patients suffering from coronary heart disease (CHD) and type 2 diabetes mellitus (T2DM). Methods: According to the research design, a randomized, double-blind, placebo-controlled trial has been implemented on 60 subjects suffering from CHD and T2DM. Therefore, participants have been randomly divided into 2 groups for taking placebo (n = 30) or 250 mg magnesium oxide plus 150 mg zinc sulfate (n = 30) for 12 weeks. Results: Magnesium and zinc significantly decreased fasting plasma glucose (FPG) (β - 9.44 mg/dL, 95 CI, - 18.30, - 0.57; P = 0.03) and insulin levels (β - 1.37 μIU/mL, 95 CI, - 2.57, - 0.18; P = 0.02). Moreover, HDL-cholesterol levels significantly enhanced (β 2.09 mg/dL, 95 CI, 0.05, 4.13; P = 0.04) in comparison to the placebo. There was an association between magnesium and zinc intake, and a significant decrease of C-reactive protein (CRP) (β - 0.85 mg/L, 95 CI, - 1.26, - 0.45; P < 0.001), a significant increase in total nitrite (β 5.13 μmol/L, 95 CI, 1.85, 8.41; P = 0.003) and total antioxidant capacity (TAC) (β 43.44 mmol/L, 95 CI, 3.39, 83.50; P = 0.03) when compared with placebo. Furthermore, magnesium and zinc significantly reduced the Beck Depression Inventory index (BDI) (β - 1.66; 95 CI, - 3.32, - 0.009; P = 0.04) and Beck Anxiety Inventory (BAI) (β - 1.30; 95 CI, - 2.43, - 0.16; P = 0.02) when compared with the placebo. Conclusions: In patients with T2DM and CHD, the 12-week intake of magnesium plus zinc had beneficial effects on FPG, HDL-cholesterol, CRP, insulin, total nitrite, TAC levels, and BDI and BAI score. This suggests that magnesium and zinc co-supplementation may be beneficial for patients with T2DM and CHD. Further studies on more patients and lasting longer are needed to determine the safety of magnesium and zinc co-supplementation. Trial registration: Current Controlled Trials http://www.irct.ir: IRCT20130211012438N31 at 11 May 2019 of registration. This study retrospectively registered. © 2020 The Author(s)
Mehanizam toksičnosti i detoksikacije organofosfornih spojeva s naglaskom na istraživanja u Hrvatskoj
This review comprises studies on the mechanisms of toxicity and detoxication of organophosphorus (OP) compounds done in Croatia in different research areas. One area is the synthesis of antidotes against OP poisoning and their in vivo testing in experimental animals. In vitro studies included in this review focus on the mechanisms of reversible inhibition of acetylcholinesterase (AChE) and butyrylcholinesterase (BChE), protection of cholinesterases from inhibition by OPs, and reactivation of phosphylated cholinesterases. The third area comprises distribution profiles of BChE and paraoxonase (PON) phenotypes in selected population groups and the detection of OPs and metabolites in humans. Finally, methods are described for the detection of OP compounds in human blood and other media by means of cholinesterase inhibitionPrikazana su istraživanja vođena u Hrvatskoj na različitim područjima mehanizma toksičnosti i detoksikacije organofosfornih (OP) spojeva. Jedno je područje sinteza antidota protiv otrovanja OP spojevima i testiranje in vivo antidota na eksperimentalnim životinjama. Istraživanja in vitro odnose se na mehanizam reverzibilne inhibicije acetilkolinesteraze (AChE) i buturilkolinesteraze (BChE), zaštitu kolinesteraza od inhibicije OP spojevima te reaktivaciju fosfiliranih kolinesteraza. Treće je područje distribucija fenotipova BChE i paraoksonaze (PON) u odabranim populacijama te detekcija OP spojeva i njihovih metabolita u ljudima. Na kraju su opisane metode detekcije OP spojeva u ljudskoj krvi i drugim medijima koje se osnivaju na inhibiciji kolinesteraza
The effect of berberine supplementation on obesity parameters, inflammation and liver function enzymes: A systematic review and meta-analysis of randomized controlled trials
Introduction: So far, no study has summarized the findings on the effects of berberine intake on anthropometric parameters, C-reactive protein (CRP) and liver enzymes. This systematic review and meta-analysis were done based upon randomized controlled trials (RCTs) to analyze the effects of berberine on anthropometric parameters, CRP and liver enzymes. Method: Following databases were searched for eligible studies published from inception to 30 July 2019: MEDLINE, EMBASE, Web of Science, Cochrane Library, PubMed and Google scholar. Necessary data were extracted. Data were pooled by the inverse variance method and expressed as mean difference with 95 Confidence Intervals (95 CI). Result: 12 studies were included. Berberine treatment moderately but significantly decreased body weight (WMD = �2.07 kg, 95 CI -3.09, �1.05, P < 0.001), body mass index (BMI) (WMD = �0.47 kg/m2, 95 CI -0.70, �0.23, P < 0.001), waist circumference (WC) (WMD = �1.08 cm, 95 CI -1.97, �0.19, P = 0.018) and C-reactive protein (CRP) concentrations (WMD = �0.42 mg/L, 95 CI -0.82, �0.03, P = 0.034). However, berberine intake did not affect liver enzymes, including alanine aminotransferase (ALT) (WMD = �1.66 I/U, 95 CI -3.98, 0.65, P = 0.160) and aspartate aminotransferase (AST) (WMD = �0.87 I/U, 95 CI -2.56, 0.82, P = 0.311). Conclusion: This meta-analysis found a significant reduction of body weight, BMI, WC and CRP levels associated with berberine intake which may have played an indirect role in improved clinical symptoms in diseases with metabolic disorders. Berberine administration had no significant effect on ALT and AST levels. © 2020 European Society for Clinical Nutrition and Metabolis
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