Display omitted
•Excellent inhibition efficiency is achieved well below the CMC.•XPS reveals interface chemistry as a function of corrosion inhibitor concentration.•Cl 2p XPS line shape of atomic ...chlorine suggests presence of interface heterogeneity.•No oxide or salt film is present on a well-inhibited carbon steel surface.
A combination of electrochemical measurement and interface analysis have been applied to characterise the interaction of OMID, an exemplar imidazoline-based corrosion inhibitor, with carbon steel in 1 M hydrochloric acid. Corrosion inhibition efficiency data indicate that excellent performance is achieved well below the critical micelle concentration. High resolution X-ray photoelectron spectra demonstrate that, as the corrosion rate decreases, the interface evolves towards one comprising OMID bound to film-free carbon steel. This latter result provides key input for those researchers attempting to predict corrosion inhibitor functionality through atomic scale interfacial modelling, and so identify next generation chemistries.
Objective:To identify the most frequent gender-specific suicide methods in Europe.Design:Proportions of seven predominant suicide methods utilised in 16 countries participating in the European ...Alliance Against Depression (EAAD) were reported in total and cross-nationally. Relative risk (RR) relating to suicide methods and gender was calculated. To group countries by pattern of suicide methods, hierarchical clustering was applied.Setting and participants:Data on suicide methods for 119 122 male and 41 338 female cases in 2000–4/5 from 16 EAAD countries, covering 52% of European population were obtained.Results:Hanging was the most prevalent suicide method among both males (54.3%) and females (35.6%). For males, hanging was followed by firearms (9.7%) and poisoning by drugs (8.6%); for females, by poisoning by drugs (24.7%) and jumping from a high place (14.5%). Only in Switzerland did hanging rank as second for males after firearms. Hanging ranked first among females in eight countries, poisoning by drugs in five and jumping from a high place in three. In all countries, males had a higher risk than females of using firearms and hanging and a lower risk of poisoning by drugs, drowning and jumping. Grouping showed that countries might be divided into five main groups among males; for females, grouping did not yield clear results.Conclusions:Research on suicide methods could lead to the development of gender-specific intervention strategies. Nevertheless, other approaches, such as better identification and treatment of mental disorders and the improvement of toxicological aid should be put in place.
Two cationic gemini surfactants having ester bonds between the hydrophobic tail and the cationic moiety have been synthesized. The ester bonds were either with the ester carbonyl group away from the ...positive charge (esterquat type arrangement) or facing the positive charge (betaine ester type arrangement). The chemical hydrolysis of the surfactants was investigated and compared with the hydrolysis of the corresponding monomeric surfactants. The betaine ester type of surfactants was found to hydrolyze much faster than the esterquat surfactants. It was also seen that above the critical micelle concentration the gemini surfactants were much more susceptible to alkaline hydrolysis than the corresponding monomeric surfactants. The biodegradation of the geminis and the monomeric surfactants were also studied. It was found that whereas the monomeric surfactants were rapidly degraded, the two gemini surfactants were more resistant to biodegradation and could not be classified as readily biodegradable. The 60% biodegradation was reached after 35–40 days. Thus, there was no correlation between rate of chemical hydrolysis and rate of biodegradation.
Base catalyzed hydrolysis of a gemini alkyl betainate surfactant may be accelerated through a neighboring group participation mechanism.
The peatland map of Europe Tanneberger, Franziska; Tegetmeyer, C; Busse, S ...
Mires and peat,
01/2017, Volume:
19, Issue:
22
Journal Article
Peer reviewed
Open access
Based on the ‘European Mires Book’ of the International Mire Conservation Group (IMCG), this article provides a composite map of national datasets as the first comprehensive peatland map for the ...whole of Europe. We also present estimates of the extent of peatlands and mires in each European country individually and for the entire continent. A minimum peat thickness criterion has not been strictly applied, to allow for (often historically determined) country-specific definitions. Our ‘peatland’ concept includes all ‘mires’, which are peatlands where peat is being formed. The map was constructed by merging national datasets in GIS while maintaining the mapping scales of the original input data. This ‘bottom-up’ approach indicates that the overall area of peatland in Europe is 593,727 km2. Mires were found to cover more than 320,000 km2 (around 54 % of the total peatland area). If shallow-peat lands (< 30 cm peat) in European Russia are also taken into account, the total peatland area in Europe is more than 1,000,000 km2 which is almost 10 % of the total surface area. Composite inventories of national peatland information, as presented here for Europe, may serve to identify gaps and priority areas for field survey, and help to cross-check and calibrate remote sensing based mapping approaches.
This article provides an overview of the effects of land-use on the fluxes of carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) and from peatlands in the Nordic countries based on the field ...data from about 100 studies. In addition, this review aims to identify the gaps in the present knowledge on the greenhouse gas (GHG) balances associated with the land-use of these northern ecosystems. Northern peatlands have accumulated, as peat, a vast amount of carbon from the atmosphere since the last glaciation. However, the past land-use and present climate have evidently changed their GHG balance. Unmanaged boreal peatlands may act as net sources or sinks for CO2 and CH4 depending on the weather conditions. Drainage for agriculture has turned peatlands to significant sources of GHGs (mainly N2O and CO2). Annual mean GHG balances including net CH4, N2O and CO2 emissions are 2260, 2280 and 3140 g CO2 eq. m−2 (calculated using 100 year time horizon) for areas drained for grass swards, cereals or those left fallow, respectively. Even after cessetion of the cultivation practices, N2O and CO2 emissions remain high. The mean net GHG emissions in abandoned and afforested agricultural peatlands have been 1580 and 500 g CO2 eq. m−2, respectively. Peat extraction sites are net sources of GHGs with an average emission rate of 770 g CO2 eq. m−2. Cultivation of a perennial grass (e.g., reed canary grass) on an abandoned peat extraction site has been shown to convert such a site into a net sink of GHGs (−330 g CO2 eq. m−2). In contrast, despite restoration, such sites are known to emit GHGs (mean source of 480 g CO2 eq. m−2, mostly from high CH4 emissions). Peatland forests, originally drained for forestry, may act as net sinks (mean −780 g CO2 eq. m−2). However, the studies where all three GHGs have been measured at an ecosystem level in the forested peatlands are lacking. The data for restored peatland forests (clear cut and rewetted) indicate that such sites are on average a net sink (190 g CO2 eq. m−2). The mean emissions from drained peatlands presented here do not include emissions from ditches which form a part of the drainage network and can contribute significantly to the total GHG budget. Peat soils submerged under water reservoirs have acted as sources of CO2, CH4 and N2O (mean annual emission 240 g CO2 eq. m−2). However, we cannot yet predict accurately the overall greenhouse gas fluxes of organic soils based on the site characteristics and land-use practices alone because the data on many land-use options and our understanding of the biogeochemical cycling associated with the gas fluxes are limited.
Adsorption of a series of ethoxylated cationic surfactants at model surfaces of alkanethiol self-assembled monolayers was studied by the surface plasmon resonance technique. Model surfaces were ...tailor-made by choosing alkanethiols or mixtures of alkanethiols with methyl, hydroxyl, carboxyl, and trimethylammonium groups in terminal position. The ethoxylated and quaternized cationic surfactants having from 2 to 18 oxyethylene units, showed a decrease in adsorbed amount with increasing oxyethylene chain length for both hydrophobic and hydrophilic surfaces. On a negatively charged surface, containing carboxylate groups, the surfactant with only two oxyethylene groups adsorbed strongly due to electrostatic attraction and the adsorption increased with increasing amount of surface carboxylate groups. This work shows the usefulness of self-assembled alkanethiols on gold as a tool for performing surfactant adsorption studies on surfaces with variable hydrophobicity and charge.
Increased oxidative stress and myocyte apoptosis co-exist in the remote non-infarcted myocardium (RM) following a large myocardial infarction. We proposed that these phenomena are causally related.
...On day 3 after induction of myocardial infarction, Sprague-Dawley rats were randomized to receive probucol and pyrrolidine dithiocarbamate (MI-T), or vehicle only (MI) for 7 weeks. Control rats (C) received vehicle. At 7 weeks, lipidperoxidation within the RM was assessed by measuring thiobarbituric acid reactive substances, which were significantly increased in MI vs. C, while MI-T was not different from C. There was a significant increase in cardiac myocytes positive for in situ TdT-UTP nick-end labeling within the RM in MI vs. C, which was inhibited in MI-T. Furthermore, internucleosomal DNA fragmentation was clearly demonstrated on agarose gels from RM in the MI group, while it was much less apparent on gels from RM in the C and MI-T groups. Western blot analysis showed a significant increase in p53, Bax and caspase-3 protein expression within the RM of MI vs. C, all of which were inhibited in the MI-T group. Furthermore, there was evidence for an increase in caspase-3 activity within the RM from MI vs. C, which was normalized in the MI-T group.
Long-term treatment with the antioxidants probucol and pyrrolidine dithiocarbamate attenuates oxidative stress, myocyte apoptosis, caspase-3 like activity and the expression of p53, bax and caspase-3 within RM in rats after a large myocardial infarction.
Display omitted
Carbon dioxide is commonly used as pH regulator in switchable surfactant systems and in the formation of alkyl ammonium-alkyl carbamate ion-pair. Its use to form a meta-stable anionic ...surfactant has been less explored and can impart a cleavable character to the amphiphile.
The reaction between CO2 and an alkylamine, N,N-di(propylamino)dodecylamine (Y12-amine), under alkaline pH conditions, produced a stable anionic carbamate-based surfactant (Y12-carbamate). By heating and exposure to N2, anionic Y12-carbamate could slowly be reverted into Y12-amine. The surface activity of Y12-amine and Y12-carbamate was investigated by surface tension measurements. To study the behavior of Y12-amine at the gas-water interface during CO2 exposure, we used the pendant drop technique with a sealed chamber where the gas composition could be controlled.
The Y12-carbamate had a higher CMC than Y12-amine at pH 12, and was also less surface active. The ion pair Y12-ammonium – Y12-carbamate, obtained at neutral pH, exhibited the lowest CMC and the highest surface activity. The interfacial formation of anionic Y12-carbamate induced an increase in surface tension. When CO2 was exchanged to N2, the migration from the bulk to the interface of Y12-amine induced a decrease in surface tension. The rate was dependent on the concentration of Y12-amine.
Overall, suicide rates in the Nordic region, Denmark, Finland, Iceland, Norway and Sweden, have declined in the past 40 years. The aim of this study was to determine trends in suicide mortality from ...2000 to 2018.
Data were obtained from official suicide statistics for men and women, 15 years and older. Gender and age groups in four calendar periods were analyzed using Joinpoint Estimated Regression Coefficient.
The crude regional suicide rate was 17.1, 2000-2004, decreased to 14.1 per 100,000 inhabitants in 2015-2018. Age-standardized rates are 13.6-11.3. The crude rate decreased by 19.5% (16.3% age-standardized), 19.3% for males and 20.5% for females. The largest decrease was found in Finland (34.9%), the smallest in Norway (1.4%). In males, the exception was an increased suicide rate among all Icelandic except 15-24-year olds, and in 45-64 year-old Norwegians. Among females, an increase was seen among 15-24-year olds in all countries except Iceland, in all age groups in Norway, and in 25-44-year olds in Sweden. In males, a decline of the suicide rated lower than 10% was noted in 25-44 olds in Norway and in 15-64 year-olds in Sweden.
A robust decrease was observed in the overall regional suicide rate in recent years. Exceptions are rising rates in Icelandic males, in Norwegian females, and the youngest female groups in all except Iceland. The small decline among middle-aged males in Norway and Sweden is of concern.
Objectives. This study was performed to determine the acute effect of cigarette smoking on proximal and distal epicardial condult and coronary resistance vessels.
Background. Cigarette smoking causes ...constriction of epicardial arteries and a decrease in coronary blood flow in patients with coronary artery disease, despite an increase in myocardial oxygen demand. The role of changes in resistance vessel tone in the acute coronary hemodynamic effect of smoking has not been examined.
Methods. Twenty-four long-term smokers were studied during cardiac catheterization after vasoactive medications had been discontinued. The effect of smoking one cigerette 10 to 15 mm long on proximal and distal conduit vessel segments was assessed before and immediately after smoking and at 5, 15 and 30 min after smoking (n = 8). To determine the effect of smoking on resistance vessels, coronary flow velocity was measured in a nonobstructed artery with a 3F intracoronary Doppler catheter before and for 5 min after smoking (n = 8). Eight patients were studied without smoking to control for spontaneous changes in conduit arterial diameter (n = 5) and vessel tone (n = 3).
Results. The average diameter of proximal coronary artery segments decreased from 2.56 ± 0.12 mm (mean ± SEM) before smoking to 2.41 ± 0.09 mm 5 min after amoking (−5 ± 2%, p < 0.05). Distal coronary diameter decreased from 1.51 ± 0.07 to 1.39 ± 0.06 mm (−8 ± 2%, p < 0.01). Marked focal vasoconstriction after smoking was observed in two patients. Coronary diameter returned to baseline by 30 min after smoking. There was no change in vessel diameter in control patients. Despite a significant increase in the heart rate-mean arterial pressure product, coronary flow velocity decreased by 7 ± 4% (p < 0.05) and coronary vascular increased by 21 ± 4% (p < 0.01) 5 min after smoking. There was no change in these variables in the control subjects.
Conclusions. Smoking causes immediate constrictioin of proximal and distil epicardial coronary arteries and an increase in coronay resistance vessel tone despite an increase in myocardial oxygen demand. These acute coronary hemodynamic effects may contribute to the adverse cardiovascular consequences of cigarette smoking.
PDF
