Molecular dynamics simulations of mixtures of the protic ionic liquid ethylammonium nitrate (EAN) and the aprotic 1-ethyl-3-methylimidazolium tetrafluoroborate (EMIMBF
4
) are reported and the ...results are compared with experimental density and electrical conductivity measurements. Essentially ideal mixing of the ionic liquids is seen to take place by means of experimental and simulated excess molar volumes, whose very low values suggest a gradual transition between the structures of the two end constituents of the mixture. A weak dominance of the structure of the protic ionic liquid is nevertheless registered, due to a slight preferential formation of the network of hydrogen bonds, as reflected in the coordination number and the number of hydrogen bonds in the mixture. A novel conductivity curve showing pronounced deviations from the simple ideal mixing rule is reported, with three different regions defined by a local maximum - reflecting enhanced translational dynamics relative to ideal mixture behaviour - and a global minimum at intermediate concentrations. The physical origin of this behaviour is discussed along with the structure and single-particle dynamics of the mixture, and it is seen that these regions are defined by the onset of the formation of the EAN hydrogen bonded network (
x
EAN
= 0.2) and the virtual disappearance of the structure of the aprotic ionic liquid at
x
EAN
= 0.7. It is concluded that the delicate interplay between both networks has a deep effect on the placement and mobility of EMIM
+
cations in the mixture all throughout the different stages of the structural transition, which seems to be the driving force behind the reported transport properties of the mixture at intermediate to high EAN concentrations.
Molecular dynamics simulations of mixtures of the protic ionic liquid EAN and the aprotic EMIMBF
4
are reported and the results are compared with experimental density and electrical conductivity measurements.
Increased arterial stiffness has been shown to predict cardiovascular risk in hypertensive patients. Our objective was to evaluate the relationship between the ambulatory arterial stiffness index ...(AASI) and subclinical organ damage (SOD). The design was a cross-sectional study. Subjects included 554 hypertensive patients with and without drug treatment (mean age 57±12 years, 60.6% men). The AASI was defined as 1 minus the regression slope of diastolic over systolic blood pressure (BP) readings obtained from 24-h recordings. Renal damage was evaluated on the basis of glomerular filtration rate (GFR) and microalbuminuria; vascular damage was measured by carotid intima-media thickness (IMT) and ankle/brachial index (ABI); and cardiac damage was evaluated on the basis of the Cornell voltage-duration product (VDP) and left ventricular mass index. The mean AASI was 0.38±0.07 (0.39±0.07 in treated patients and 0.37±0.06 in nontreated subjects). The AASI showed a positive correlation with IMT (r=0.417, P<0.001) and Cornell VDP (r=0.188, P<0.001), and a negative correlation with GFR (r=-0.205, P=0.001) and the ABI. The variables associated with the presence of SOD were AASI (odds ratio (OR)=3.89) and smoking (OR=1.55). The variables associated with IMT were smoking and waist circumference, whereas those associated with GFR were AASI, body mass index and waist circumference. In turn, smoking, total cholesterol and glycosylated hemoglobin A1c were associated with the ABI. Increased AASI implies a greater presence of SOD in primary hypertensive patients with or without BP-lowering drug treatment.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
OBJECTIVE:To analyze the reliability and validity of a semiautomated tool for assessing retinal vessel caliber and to describe the relationship of measures taken to cardiovascular risk and target ...organ damage.
METHODS:A total of 210 patients aged 34–75 years were selected with retinography. Retinal photographs were digitized, and superior and inferior temporal vessels were measured in an area 0.5–1 disk diameter from the optic disc with semiautomated software arteriole/venule index (AVIx) calculator. AVIx was also estimated. Vascular damage was assessed using carotid intima–media thickness and pulse wave velocity, cardiac damage using Cornell voltage–duration product, renal damage using the glomerular filtration rate and microalbuminuria, and cardiovascular risk with the Framingham score.
RESULTS:Interobserver intraclass correlation coefficient (ICC) ranged from 0.96 95% confidence interval (CI) 0.94–0.97 to 0.99 (95% CI 0.98–0.99), and intraobserver ICC ranged from 0.97 (95% CI 0.94–0.98) to 0.99 (95% CI 0.99–0.99). In the Bland–Altman plot, the limit of interobserver agreement was −0.009 (0.066 to −0.086) in right AVIx and −0.001 (0.083 to −0.085) in left AVIx, whereas the limit of intraobserver agreement for overall AVIx was −0.005 (−0.057 to −0.047). Cardiovascular risk and albumin-creatinine ratio were higher in the first tertile of AVIx as compared with the other two (P < 0.05). In multiple regression, AVIx and venule caliber, but not artery caliber, behaved as predictors of cardiovascular risk and microalbuminuria.
CONCLUSION:This tool showed a high intraobserver and interobserver reliability, and results of the validity analysis agree with those from large studies in estimation of cardiovascular risk and evaluation of target organ damage.
Despite the growing interest in the potential electrochemical applications of both aluminium and ionic liquids in batteries, the microstructure of mixtures of trivalent salts and these dense ionic ...environments is completely unknown. In this work, the solvation of Al
3+
cations in highly dense ionic solvents is investigated. For this purpose, molecular dynamics simulations of mixtures of a protic ionic liquid, ethylammonium nitrate (EAN), with aluminium nitrate (Al(NO
3
)
3
), both in bulk and confined between graphene walls, are performed. Several structural quantities of the system are calculated for different salt concentrations, such as densities, radial distribution functions, structure factors, coordination numbers and hydrogen bonds for the bulk mixture and ionic density profiles for the confined ones. Moreover, vibrational density of states is calculated for the salt cations, both in bulk and when close to the walls. The results obtained are analyzed and compared to those for mixtures of EAN with monovalent and divalent salts, in order to probe the influence of the salt cation charge on the system's properties. Finally,
ab initio
density functional theory calculations were performed in order to analyze the structure of the Al
3+
-ligand complexes, and their predictions for the Raman spectrum are compared both to the corresponding experimental one and the one coming from molecular dynamics simulations. According to our calculations, Al(NO
3
)
6
3−
octahedral complexes do not significantly change the microstructure of the mixtures relative to those of Mg
2+
-based ones.
Nanostructured solvation of Al
3+
in an EAN ionic liquid, forming octahedral complexes with nitrate anions.
Despite the growing interest in the potential electrochemical applications of both aluminium and ionic liquids in batteries, the microstructure of mixtures of trivalent salts and these dense ionic ...environments is completely unknown. In this work, the solvation of Al3+ cations in highly dense ionic solvents is investigated. For this purpose, molecular dynamics simulations of mixtures of a protic ionic liquid, ethylammonium nitrate (EAN), with aluminium nitrate (Al(NO3)3), both in bulk and confined between graphene walls, are performed. Several structural quantities of the system are calculated for different salt concentrations, such as densities, radial distribution functions, structure factors, coordination numbers and hydrogen bonds for the bulk mixture and ionic density profiles for the confined ones. Moreover, vibrational density of states is calculated for the salt cations, both in bulk and when close to the walls. The results obtained are analyzed and compared to those for mixtures of EAN with monovalent and divalent salts, in order to probe the influence of the salt cation charge on the system's properties. Finally, ab initio density functional theory calculations were performed in order to analyze the structure of the Al3+-ligand complexes, and their predictions for the Raman spectrum are compared both to the corresponding experimental one and the one coming from molecular dynamics simulations. According to our calculations, Al(NO3)63- octahedral complexes do not significantly change the microstructure of the mixtures relative to those of Mg2+-based ones.
To analyse the relationship between various parameters derived from ambulatory blood pressure monitoring (ABPM) and vascular, cardiac and renal target organ damage.
A cross-sectional, descriptive ...study. It included 353 patients with short-term or recently diagnosed hypertension.
ABPM, carotid intima-media thickness (IMT), Cornell voltage-duration product (Cornell VDP), glomerular filtration rate and albumin/creatinine ratio to assess vascular, cardiac and renal damage.
Two hundred and twenty-three patients (63.2%) were males, aged 56.12+/-11.21 years. The nocturnal fall in blood pressure was 11.33+/-8.41, with a dipper pattern in 49.0% (173), nondipper in 30.3% (107), extreme dipper in 12.7% (45) and riser in 7.9% (28). The IMT was lower in the extreme dipper (0.716+/-0.096 mm) and better in the riser pattern (0.794+/-0.122 mm) (P<0.05). The Cornell VDP and albumin/creatinine ratio were higher in the riser pattern (1818.94+/-1798.63 mm/ms and 140.78+/-366.38 mg/g, respectively) than in the other patterns. In the multivariate analysis after adjusting for age, sex and antihypertensive treatment, with IMT as dependent variable the 24-h pulse pressure (beta = 0.003), with Cornell VDP the rest pulse pressure (beta = 12.04), and with the albumin/creatinine ratio the percentage of nocturnal fall in systolic blood pressure (beta = -3.59), the rest heart rate (beta = 1.83) and the standard deviation of 24-h systolic blood pressure (beta = 5.30) remain within the equation.
The estimated pulse pressure with ABPM is a predictor of vascular and cardiac organ damage. The nocturnal fall and the standard deviation in 24-h systolic blood pressure measured with the ABPM is a predictor of renal damage.
Canine adenovirus type 1 (CAdV‐1) is responsible for infectious canine hepatitis. The disease has been described in captive American black bear (Ursus americanus) and European brown bear (Ursus ...arctos arctos), with just one recently reported case in a cub of a free‐ranging brown bear (Ursus arctos horribilis) from Alaska. The aim of this work is to summarize findings related to presence and associated mortality of CAdV‐1 in 21 free‐ranging Cantabrian brown bears (Ursus arctos arctos) submitted to necropsy in Asturias and Castilla y León (northwestern Spain) from 1998 to 2018. On the basis of the anatomopathological findings and laboratory results three free‐ranging brown bears died due to infectious canine hepatitis, which is to our knowledge the first description of death due to this disease in free‐ranging bears in Europe. Gross lesions consisted of petechial haemorrhages and congestion in different internal organs, haemorrhagic fluid in internal cavities, friable and yellowish liver and thickening of gall bladder. Microscopic lesions were observed mainly in liver, kidney and brain and consisted of multifocal necrosis of cells with presence of basophilic intranuclear inclusions. Immunohistochemical (IHC) and real‐time polymerase chain reaction (qPCR) techniques were used to assess the presence of CAdV‐1 in paraffin‐embedded liver samples. Viral antigens were detected by IHC labelling within hepatocytes and Küppfer cells in the three animals. The presence of viral DNA was confirmed by qPCR in one of them. In order to evaluate the circulation of CAdV‐1 in brown bears, a retrospective study was performed using both IHC and qPCR techniques in 11 and 12 additional brown bears, respectively. An extra brown bear was found positive by IHC. This study shows that CAdV‐1 surveillance of brown bears and sympatric carnivores should be considered as major concern for the monitoring the population evolution throughout time in this endangered species.
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BFBNIB, DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UILJ, UKNU, UL, UM, UPUK
To evaluate the usefulness of the diagnostic tests recommended by the European Society of Hypertension/Cardiology Guidelines (ESH-ESC 2007) in hypertensive patients classified as being at low or ...moderate risk, analyzing the change to high risk classification and the characteristics associated with such change.
A cross-sectional study was made in 391 patients aged between 30 and 80 years recently diagnosed with arterial hypertension in the Primary Care setting. The criteria of the 2007 ESH-ESC Guidelines were followed for the evaluation of risk factors, subclinical organ damage, cardiovascular disease and cardiovascular risk. In addition to the routine tests, echocardiography, carotid ultrasound, albumin/creatinine ratio, estimated glomerular filtration rate, ankle-brachial index, pulse wave velocity and retinography were used. We established four levels of testing performed for risk classification.
Using the routine tests to evaluate risk (level 1), 218 (55.8%) patients were classified as being at high risk. Of the 173 patients classified as presenting low or moderate risk, the ankle-brachial index, albumin/creatinine ratio and glomerular filtration rate were determined (level 2), and 18 patients (10.4%) were classified as being at high risk. With echocardiography and carotid ultrasound (level 3), another 16 patients (10%) were raised to high risk. Finally, with pulse wave velocity and retinography (level 4), 10 additional patients (5%) were classified as presenting high risk. Patients with increased blood pressure, advanced age and women showed a 4.28-fold (95%CI: 2.01-9.16), 3.54-fold (95%CI: 1.61-7.77) and 1.36-fold (95%CI: 0.62-3.00) higher probability of being reclassified to high cardiovascular risk, respectively.
With the non-routine tests, 25.4% of the low or moderate risk patients were reclassified as presenting high risk.
•Mixtures of ethylammonium nitrate ionic liquid and inorganic salts.•Influence of cation valence on physicochemical properties.•Structure determined by ion packing, hydrogen bonding, electrostatic ...and van der Waals forces.•Solid-like structures in the polar regions determine concentration dependence of physical properties.•Long-lived cation anion aggregates formed in the bulk mixtures.
We report a systematic study of the effect of salt concentration and its cation valence on several equilibrium and transport properties of mixtures of the model protic ionic liquid ethylammonium nitrate with monovalent (LiNO3), divalent (Mg(NO3)2 and Ca(NO3)2), and trivalent (Al(NO3)3) salts. These properties, determined by appropriate experimental techniques, include density, sound velocity, refractive index, surface tension, conductivity and viscosity. Single-particle dynamics and radial distribution functions were also analyzed by means of molecular dynamics simulations. The temperature dependence of the conductivity was studied in the Vogel-Fulcher-Tammann framework, and we obtained effective activation energies, fragility indexes, and Vogel temperatures. In addition, we performed a high-temperature Arrhenius analysis and we calculated the activation energies of both conductivity and viscosity. Finally, the exponents of the fractional Walden rule for the different mixtures were obtained and the ionicities and fragilities of the systems were analyzed, proving that all the mixtures are subionic and fragile. The distortion of the network of hydrogen bonds characteristic of protic ionic liquids and the formation of long-lived anionic aggregates composed of the cations of the added salt and the nitrate anions in their first solvation shell were found to have a deep impact on the analyzed properties. The role of the surface charge density of the salt cations on the structure and transport properties of the solutions is detailedly analyzed and related to solvation of salt species in the polar nanoregions of the ionic liquid (nanostructured solvation).
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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