Lithofacies belonging to mud-flat and palustrine deposits (lake margin) in the Miocene of the Madrid Basin (Spain) have been studied. Four lithofacies corresponding to mud flat (1 and 3) and ...palustrine (2 and 4) deposits have been differentiated. Units 1 and 3 consist mainly of mudstones and carbonates (calcretes and diolocretes). The clay fraction is dominated by trioctahedral smectite (up to 79%) with illite and kaolinite as minor components. The d(060) spacing value shows reflections at 1.52 and 1.50 Å indicating also the presence of dioctahedral phyllosilicates. Unit 2 consists predominantly of lutites (claystones), locally with carbonate and chert nodules. The clay fraction is dominated by sepiolite (up to 96%) with variable contents of smectite and subordinate illite. The d(060) spacing value shows reflections at 1.51 and 1.52 Å indicating trioctahedral clay minerals. Unit 4 consists mostly of carbonates (limestones) with mudstone and lutite inserts. The clay fraction shows different contents of sepiolite, palygorskite and dioctahedral smectite. The analysis of a selection of trace elements (Cr, Co, Th, La, Sc) has allowed us to determine the characteristics of the source area as dioritic, somewhat different from those of the nearby materials from the Batallones sector. Sepiolite shows FWHM values ranging between 0.68 and 1.10 (2θ), indicating “low crystallinity sepiolite”. Differences in the conditions of formation of magnesian smectite and palygorskite have been observed in the mud-flat and palustrine deposits. The formation of sepiolite mainly by neoformation in palustrine deposits with different hydrochemistry is remarkable, leading to differences in fibre size and crystallinity of the fibrous clay mineral. Authigenic transformation processes from previous Al-rich phases would be responsible for the formation of saponite and palygorskite in mud flat and palustrine environments, with different pH conditions.
The commercial feasibility of alkaline-exchange membrane fuel cells and electrolyzers passes by the development of hydrogen oxidation and evolution reaction (HOR/HER) catalysts featuring an activity ...and/or cost advantage over platinum, which remains the most active metal for these processes. Among these alternatives, Pd appears as a promising candidate, since its price is typically 2-3 fold lower than that of Pt. With this motivation, the first section of this study displays our attempts at quantifying the kinetic parameters of the HOR/HER on bulk Pd in 0.1 M NaOH, which were prevented by the simultaneous absorption of hydrogen into bulk palladium. We succeeded at circumventing this issue by depositing Pd-adlayers on a polycrystalline Au-substrate by galvanic displacement of underpotentially-deposited Cu or by electrochemical plating of Pd2+. The resulting surfaces appear to consist of three-dimensional Pd-structures of an unknown thickness that we believe to scale with the palladium coverage, θPd/Au. This last parameter is inversely proportional to the HOR/HER-activity of the Pd-on-Au surfaces, in agreement with numerous theoretical and experimental studies in acid media that correlate this effect to the tensile strain induced by the Au-substrate on the Pd-lattice.
Tuning the surface structure at the atomic level is of primary importance to simultaneously meet the electrocatalytic performance and stability criteria required for the development of ...low-temperature proton-exchange membrane fuel cells (PEMFCs). However, transposing the knowledge acquired on extended, model surfaces to practical nanomaterials remains highly challenging. Here, we propose 'surface distortion' as a novel structural descriptor, which is able to reconciliate and unify seemingly opposing notions and contradictory experimental observations in regards to the electrocatalytic oxygen reduction reaction (ORR) reactivity. Beyond its unifying character, we show that surface distortion is pivotal to rationalize the electrocatalytic properties of state-of-the-art of PtNi/C nanocatalysts with distinct atomic composition, size, shape and degree of surface defectiveness under a simulated PEMFC cathode environment. Our study brings fundamental and practical insights into the role of surface defects in electrocatalysis and highlights strategies to design more durable ORR nanocatalysts.
In patients with type 2 diabetes, the prevalence of hypertension is higher than in non-diabetic subjects. Despite the high cardiovascular risk involving hypertension in these patients, its prevalence ...and control are not well known. The aims of this study were: to estimate the hypertension prevalence, awareness, treatment and control in Spanish adults with type 2 diabetes attended in Primary Care; and to analyse its time trend from 2003 to 2009. A serial cross-sectional study from 2003 to 2009 was performed in 21 Primary Care Centres in Madrid. The study population comprised all patients with diagnosed type 2 diabetes in their computerised medical history. Overall annual prevalence during the period 2003-2009 was calculated from and according to sex and age groups. Linear trend tests, regression lines and coefficients of determination were used. In 2003 89.78% (CI 87.92-91.64) of patients with type 2 diabetes suffered hypertension and 94.76% (CI: 92.85-96.67) in 2009. This percentage was greater for women and for patients over 65 years old. 30% of patients suffered previously undiagnosed hypertension in 2003 and 23.1% in 2009. 97% of diagnosed patients received pharmacological treatment and 28.79% reached the blood pressure objective in 2009. The average number of antihypertensive drugs taken was 2.72 in 2003 and 3.27 in 2009. Only 5.2% of patients with type 2 diabetes show blood pressure levels below 130/80 mmHg. Although significant improvements have been achieved in the diagnosis and control of hypertension in people with type 2 diabetes, these continue to remain far from optimum.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Paralogues pairs are more frequently observed in eels (Anguilla sp.) than in other teleosts. The paralogues often show low phylogenetic distances; however, they have been assigned to the third round ...of whole genome duplication (WGD), shared by all teleosts (3R), due to their conserved synteny. The apparent contradiction of low phylogenetic difference and 3R conserved synteny led us to study the duplicated gene complement of the freshwater eels. With this aim, we assembled de novo transcriptomes of two highly relevant freshwater eel species: The European (Anguilla anguilla) and the Japanese eel (Anguilla japonica). The duplicated gene complement was analysed in these transcriptomes, and in the genomes and transcriptomes of other Actinopterygii species. The study included an assessment of neutral genetic divergence (4dTv), synteny, and the phylogenetic origins and relationships of the duplicated gene complements. The analyses indicated a high accumulation of duplications (1217 paralogue pairs) among freshwater eel genes, which may have originated in a WGD event after the Elopomorpha lineage diverged from the remaining teleosts, and thus not at the 3R. However, very similar results were observed in the basal Osteoglossomorpha and Clupeocephala branches, indicating that the specific genomic regions of these paralogues may still have been under tetrasomic inheritance at the split of the teleost lineages. Therefore, two potential hypotheses may explain the results: i) The freshwater eel lineage experienced an additional WGD to 3R, and ii) Some duplicated genomic regions experienced lineage specific rediploidization after 3R in the ancestor to freshwater eels. The supporting/opposing evidence for both hypotheses is discussed.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Implementation of a standardized language in Nursing Care Plans (SNCP) allows for increased efficiency in nursing data management. However, the potential relationship with patientś health outcomes ...remains uncertain. The aim of this study was to evaluate the effectiveness of SNCP implementation, based on North American Nursing Diagnosis Association (NANDA) and Nursing Interventions Classification (NIC), in the improvement of metabolic, weight, and blood pressure control of Type 2 Diabetes Mellitus (T2DM) patients.
A two-year prospective follow-up study, in routine clinical practice conditions. 31 primary health care centers (Spain) participated with 24,124 T2DM outpatients. Data was collected from Computerized Clinical Records; SNCP were identified using NANDA and NIC taxonomies. Descriptive and ANCOVA analyses were conducted.
18,320 patients were identified in the Usual Nursing Care (UNC) group and 5,168 in the SNCP group. At the two-year follow-up, the SNCP group improved all parameters except LDL cholesterol and diastolic blood pressure. We analyzed data adjustming by the baseline value for these variables and variables with statistically significant differences between groups at baseline visit. Results indicated a lowering of all parameters except HbA1c, but a statistically significant reduction was only observed with diastolic blood pressure results. However, the adjusted reduction of diastolic blood pressure is of little clinical relevance. Greater differences of control values for diastolic blood pressure, HbA1c, LDL-cholesterol and Body Mass Index were found in the SNCP group, but only reached statistical significance for HbA1c. A greater proportion of patients with baseline HbA1c ≥7 decreased to <7% at the two-year follow-up in the SNCP group than in the UNC group (16.9% vs. 15%; respectively; p = 0.01).
Utilization of SNCP was helpful in achieving glycemic control targets in poorly controlled patients with T2DM (HbA1c ≥7%). Diastolic blood pressure results were slightly improved in the SNCP group compared to the UNC group.
ClinicalTrials.gov NCT01482481.
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Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Two major challenges that impede fuel cell technology breakthrough are the insufficient activity of the electrocatalysts for the oxygen reduction reaction and their degradation during operation, ...caused by the potential‐induced corrosion of their carbon‐support upon fuel cell operation. Unsupported electrocatalysts derived from tailored noble‐metal nanostructures are superior to the conventional carbon‐supported Pt nanoparticle catalysts and address these barriers by fine‐tuning the surface composition and eliminating the support. Herein, recent efforts and achievements in the design, synthesis and characterization of unsupported electrocatalysts are reviewed, paying special attention to noble‐metal aerogels, nano/meso‐structured thin films and template‐derived metal nanoarchitectures. Their electrocatalytic performances for oxygen reduction are compared and discussed, and examples of successful catalyst transfer to polymer electrolyte fuel cells are highlighted. This report aims to demonstrate the potential and challenges of implementing unsupported catalysts in fuel cells, thereby providing a perspective on the further development of these materials.
Unsupported electrocatalysts derived from tailored noble metal nanostructures emerged as a promising catalyst candidate for fuel cells due to the elimination of support corrosion. Recent advances in the design, synthesis and characterization of carbon‐free electrocatalysts are summarized. Their electrocatalytic performances for oxygen reduction are compared and discussed, and examples of successful catalyst transfer to polymer electrolyte fuel cells are highlighted.
Our progressive transition from a society energetically dependent on fossil fuels towards one relying on renewable sources requires novel, environmentally friendly energy conversion and storage ...concepts. Hydrogen is widely regarded as an energy carrier that could circumvent this need, particularly in sight of the foreseeable spread of fuel cell cars that would use this “renewable H2”. The latter would be produced using electrolyzers, which in their better established form cannot fulfill the targeted H2-price due to the low current densities (<0.5Acmgeom−2) associated to their liquid electrolyte. Alternatively, devices based on proton- and anion-exchange membranes are currently under development, and a new kind of co-electrolysis cell in which CO2 is reduced into hydrocarbons is also envisaged. Electrocatalysts play a crucial role in all of these systems, but the interplay between their surface and the reaction medium (in the so-called interface) is often overlooked in the quest towards better performance. With this motivation, this review discusses the current knowledge of the interfacial catalysis of the three (co-)electrolysis relevant reactions (i.e., the evolution of H2 and O2, and the reduction of CO2). From this, we identify pH and surface oxidation state as the key electrolyte- and surface-related parameters for which further understanding could lead to improved kinetics, and propose strategies for the tentative design of better electrocatalysts.
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•Penetration of Renewable Power Sources calls for flexible energy storage options.•Water and CO2 (co-)electrolysis will help to shape future energy systems.•Interfacial aspects of the reactions determine device efficiency and selectivity.
Computerized Clinical Records, which are incorporated in primary health care practice, have great potential for research. In order to use this information, data quality and reliability must be ...assessed to prevent compromising the validity of the results.The aim of this study is to validate the diagnosis of hypertension and diabetes mellitus in the computerized clinical records of primary health care, taking the diagnosis criteria established in the most prominently used clinical guidelines as the gold standard against which what measure the sensitivity, specificity, and determine the predictive values.The gold standard for diabetes mellitus was the diagnostic criteria established in 2003 American Diabetes Association Consensus Statement for diabetic subjects. The gold standard for hypertension was the diagnostic criteria established in the Joint National Committee published in 2003.
A cross-sectional multicentre validation study of diabetes mellitus and hypertension diagnoses in computerized clinical records of primary health care was carried out. Diagnostic criteria from the most prominently clinical practice guidelines were considered for standard reference.Sensitivity, specificity, positive and negative predictive values, and global agreement (with kappa index), were calculated. Results were shown overall and stratified by sex and age groups.
The agreement for diabetes mellitus with the reference standard as determined by the guideline was almost perfect (κ=0.990), with a sensitivity of 99.53%, a specificity of 99.49%, a positive predictive value of 91.23% and a negative predictive value of 99.98%.Hypertension diagnosis showed substantial agreement with the reference standard as determined by the guideline (κ=0.778), the sensitivity was 85.22%, the specificity 96.95%, the positive predictive value 85.24%, and the negative predictive value was 96.95%. Sensitivity results were worse in patients who also had diabetes and in those aged 70 years or over.
Our results substantiate the validity of using diagnoses of diabetes and hypertension found within the computerized clinical records for epidemiologic studies.
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Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
ObjectivesTo validate the diagnoses of acute myocardial infarction (AMI) and stroke recorded in electronic medical records (EMR) and to estimate the population prevalence of both diseases in people ...aged ≥18 years.DesignCross-sectional validation study.Setting45 primary care centres.ParticipantsSimple random sampling of diagnoses of AMI and stroke (International Classification of Primary Care-2 codes K75 and K90, respectively) registered by 55 physicians and random age-matched and sex-matched sampling of the records that included in primary care EMRs in Madrid (Spain).Primary and secondary outcome measuresSensitivity, specificity, positive and negative predictive values and overall agreement were calculated using the kappa statistic. Applied gold standards were ECGs, brain imaging studies, hospital discharge reports, cardiology reports and neurology reports. In the case of AMI, the ESC/ACCF/AHA/WHF Expert Consensus Document was also used. Secondary outcomes were the estimated prevalence of both diseases considering the sensitivity and specificity obtained (true prevalence).ResultsThe sensitivity of a diagnosis of AMI was 98.11% (95% CI, 96.29 to 99.03), and the specificity was 97.42% (95% CI, 95.44 to 98.55). The sensitivity of a diagnosis of stroke was 97.56% (95% CI, 95.56 to 98.68), and the specificity was 94.51% (95% CI, 91.96 to 96.28). No differences in the results were found after stratification by age and sex (both diseases). The prevalence of AMI and stroke was 1.38% and 1.27%, respectively.ConclusionThe validation results show that diagnoses of AMI and stroke in primary care EMRs constitute a helpful tool in epidemiological studies. The prevalence of AMI and stroke was lower than 2% in the population aged over 18 years.
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