Detecting subcropping mineralizations but also deeply buried mineralizations is one important goal in geochemical exploration. The identification of useful indicators for mineralization is a ...difficult task, as mineralization might be influenced by many factors, including location, investigated media and depth. Here, a statistical method is proposed which indicates chemical elements related to mineralization along a transect. Moreover, the method determines the potential area of the deposit along a transect. The identification is based on general additive models (GAMs) for the element concentrations across the spatial coordinate(s). The log-ratios of the GAM fits are taken to compute the curvature, where high and narrow curvature is supposed to indicate the mineralization area. By defining a measure for the quantification of high curvature, the log-ratios can be ranked, and elements can be identified that are indicative of the anomaly patterns.
The important goals of mineral exploration geochemistry are detection and identification of underlying mineralization. This paper deals with element concentration data analyzed of surface geochemical ...samples acquired from soil horizons or plants. A new unsupervised procedure is proposed for this purpose when the samples have been taken on a regular or irregular grid in the area under investigation. The methodology is based on Generalized Additive Model fits on element concentration data. Then new data points are taken of the surface of the smooth fits across the entire sampling area as a regular grid. Pairwise log-ratios of elements are then calculated of these points, and curvature of the log-ratio pairs is computed. High curvature indicates abrupt spatial changes, which could point at locations of mineralized zones. A measure called
c
-value evaluates the overall curvature and thus serves as an importance measure of a log-ratio pair. The methodology is tested on two real surface geochemical data sets collected in areas with known underlying mineralization, and the results confirm existing knowledge of the underlying mineralization.
Background: For improving health literacy (HL) by national and international public health policy, measuring population HL by a comprehensive instrument is needed. A short instrument, the HLS19-Q12 ...based on the HLS-EU-Q47, was developed, translated, applied, and validated in 17 countries in the WHO European Region. Methods: For factorial validity/dimensionality, Cronbach alphas, confirmatory factor analysis (CFA), Rasch model (RM), and Partial Credit Model (PCM) were used. For discriminant validity, correlation analysis, and for concurrent predictive validity, linear regression analysis were carried out. Results: The Cronbach alpha coefficients are above 0.7. The fit indices for the single-factor CFAs indicate a good model fit. Some items show differential item functioning in certain country data sets. The regression analyses demonstrate an association of the HLS19-Q12 score with social determinants and selected consequences of HL. The HLS19-Q12 score correlates sufficiently highly (r ≥ 0.897) with the equivalent score for the HLS19-Q47 long form. Conclusions: The HLS19-Q12, based on a comprehensive understanding of HL, shows acceptable psychometric and validity characteristics for different languages, country contexts, and methods of data collection, and is suitable for measuring HL in general, national, adult populations. There are also indications for further improvement of the instrument.
and purpose: It is unclear whether intravenous thrombolysis (IVT) outperforms early dual antiplatelet therapy (DAPT) in the acute setting of mild ischemic stroke. The aim of this study was to compare ...early safety and efficacy of IVT to DAPT.
Data of mild non-cardioembolic stroke patients with admission NIHSS <=3 who received IVT or early DAPT in the period 2018-2021 were extracted from a nationwide, prospective stroke unit registry. Study endpoints included symptomatic intracerebral hemorrhage (sICH), early neurological deterioration ≥4 NIHSS points (END), and 3-months functional outcome by modified Rankin Scale (mRS).
1195 mild stroke patients treated with IVT and 2625 treated with DAPT were included. IVT patients were younger (68.1 versus 70.8 years), had less hypertension (72.8% versus 83.5%), diabetes (19% versus 28.8%) and history of myocardial infarction (7.6% versus 9.2%) and slightly higher admission NIHSS scores (median 2 versus median 1) as compared to DAPT patients. After propensity score matching and multivariable adjustment, IVT was associated with sICH (4 (1.2%) vs 0), END (aOR 2.8, CI 1.1-7.5), and there was no difference in mRS 0-1 at 3 months (aOR 1.3, CI 0.7-2.6).
This analysis from a prospective nationwide stroke unit network indicates that IVT is not superior to DAPT in the setting of mild non-cardioembolic stroke and may eventually be associated with harm. Further research focusing on acute therapy of mild stroke is highly warranted.
This study provides Class III evidence that IVT is not superior to dual antiplatelet therapy in patients with acute mild (NIHSS<=3) non-cardioembolic stroke. The study lacks the statistical precision to exclude clinically important superiority of either therapy.
Background and Purpose Studies on mechanical thrombectomy (MT) in acute ischemic stroke (AIS) patients with preexisting disability are limited. We aimed to compare the outcomes of MT versus best ...medical treatment (BMT) in these patients. Methods In the nationwide Austrian registry and Swiss monocentric registry, we identified 462 AIS patients with pre-stroke disability (modified Rankin Scale mRS score ≥3) and acute large vessel occlusion. The primary outcome was returning to pre-stroke mRS or better at 3 months. Secondary outcomes were early neurological improvement (National Institutes of Health Stroke Scale score improvement ≥8 at 24 to 48 hours), 3-month mortality, and symptomatic intracerebral hemorrhage (sICH). Multivariable regression models and propensity score matching (PSM) were used for statistical analyses. Results Compared with the BMT group (n=175), the MT group (n=175) had younger age, more severe strokes, and lower pre-stroke mRS, but similar proportion of receiving intravenous thrombolysis. MT was associated with higher odds of returning to baseline mRS or better at 3 months (adjusted odds ratio aOR, 2.5; 95% confidence interval CI, 1.39 to 4.47), early neurological improvement (aOR, 2.62; 95% CI, 1.41 to 4.88), and lower risk of 3-month mortality (aOR, 0.29; 95% CI, 0.18 to 0.49). PSM analysis showed similar findings. MT was not associated with an increased risk of sICH (4.0% vs. 2.1% in all patients; 4.2% vs. 2.4% in the PSM cohort). Conclusions MT in patients with pre-stroke mRS ≥3 might improve the 3-month outcomes and short-term neurological impairment, suggesting that pre-stroke disability alone should not be a reason to withhold MT, but that individual case-by-case decisions may be more appropriate.
Introduction:
To date, risk assessment of suffering ischemic and hemorrhagic stroke in individuals under oral anticoagulation (OAC) is limited to hospital-based cohorts and patients with atrial ...fibrillation.
Patients and methods:
Through the combination of three individual datasets, (1) the population-based Tyrolean Stroke Pathway database, prospectively documenting all (unselected) stroke patients in the entire federal state of the Tyrol and (2) nation-wide prescription data, detailing each reimbursed prescription in Austria as well as (3) the Austrian Stroke Unit Registry, a nation-wide registry comprising data on all patients admitted to any of the 38 stroke units in Austria, we assessed risk of stroke in patients with prior oral anticoagulation and compared characteristics of patients taking direct oral anticoagulants and Vitamin-K-Antagonists.
Results:
In Austria, oral anticoagulant prescription reimbursements increased from 292,475 in 2015 to 389,407 in 2021. In the Tyrol, prior oral anticoagulation treatment was evident in 586 of 3861 (15.2%) patients with ischemic and 131 of 523 (25.0%) with hemorrhagic stroke, with 20% and 35% of those stroke patients respectively having prior oral anticoagulation due to other indications than non-valvular atrial fibrillation. Considering prescription rates, treatment with direct oral anticoagulants was associated with a reduced stroke risk compared to Vitamin-K-Antagonists, especially in ischemic (1.05% vs 0.62%; RR 0.59, p < 0.001) but also in hemorrhagic stroke, even if less pronounced (0.21% vs 0.14%; RR 0.68, p = 0.06). In Austria, prior intake of direct oral anticoagulants was associated with lower risk of suffering acute large vessel occlusion stroke (RR 0.79, p = 0.003).
Discussion and conclusions:
One in seven patients suffering ischemic and one in four suffering hemorrhagic stroke had prior oral anticoagulation treatment. Both ischemic and hemorrhagic strokes are less frequent in those with direct oral anticoagulant intake compared to those taking Vitamin-K-Antagonists. Establishment of clear standard operating procedures on how to best care for acute stroke patients with oral anticoagulation is essential.
Graphical abstract
Mineral exploration is increasingly challenging in inhabited areas. To evaluate the potential of soil analysis by pXRF (portable X-ray fluorescence) as a low-footprint exploration technique, we ...revisited a historic Sb district in an agricultural area and performed shallow-soil sampling (Ah and B horizons) along profiles across known veins to capture the endogenic geochemical anomaly signals. Despite an expected bias between pXRF measurements and laboratory analyses, the former effectively located the Sb veins, especially when using their multi-element capabilities. Composition data processing (CoDa) and horizon-selective sampling significantly improved the method’s efficiency. On-site measurements allow dynamic sampling and mapping, helping with faster, cost-effective sample selection for further laboratory investigations. Based on this case study, where similar geochemical patterns were obtained for both horizons, application of an on-site approach to a humic horizon can increase survey efficiency and decrease impacts.
Background: Intravenous thrombolysis (IVT) is an approved treatment for patients with acute ischemic stroke irrespective of sex. However, the current literature on sex differences in functional ...outcomes following IVT is inconsistent. So far, a number of studies - including a previous analysis based on data from the Austrian Stroke Unit Registry (ASUR) – detected significant sex-related differences in functional outcome, while others did not report any differences between women and men. In addition, currently there is a lack of data on how sex-related differences evolve over time. Aims: To assess time trends of sex-related differences in functional outcome of ischemic stroke in a large nationwide cohort and to investigate associations of patient characteristics with functional outcome post thrombolysis in women and men. These data will offer crucial insights into whether sex differences in functional outcome persist despite the large advances in acute stroke treatment. Methods: We analyzed retrospective data of consecutive patients with acute ischemic stroke treated with IVT in 39 stroke centers contributing to the ASUR between 2006 and 2021. We included patients over 18 years of age diagnosed with an acute ischemic stroke who received IVT and with available data on functional outcome at 3 months after treatment. The primary outcome parameter was favorable functional outcome (modified Rankin Scale (mRS) of 0-2) at 3 months. Multivariable logistic regression analysis was performed in the overall population and stratified by sex to assess associations of baseline characteristics with functional outcome. Results: Among 11840 patients receiving IVT, 2489/5503 (45.4%) women achieved favorable functional outcome compared to 3787/6337 (59.8%) men. Overall, female sex was a statistically significant predictor of functional outcome after thrombolysis, but additional predictors of outcome differed between women and men. Female sex was independently associated with decreased chances of achieving functional independency (adjOR 0.87, 95%CI 0.79-0.96, p=0.005) and we detected a statistically significant improvement in functional outcome over time only in men (year of treatment, adjOR (per year) 1.04, 95%CI 1.02-1.06, p<0.001) but not in women (adjOR (per year) 1.01, 95%CI 0.99-1.03, p=0.280). Hypertension, smoking, and longer or unknown onset-to-door times were statistically significant predictors of outcome only in male patients, whereas atrial fibrillation, prior myocardial infarction and longer door-to-needle times were significantly associated with outcome only in women. Conclusions: Sex differences in functional outcome after IVT for acute ischemic stroke are persisting over the past years. Results of our analysis can increase awareness and a resulting focus on sex differences in predictors of outcome could be helpful in mitigating these differences in the future by supporting a more individualized patient care in clinical routine. Follow-up analyses are needed to assess this potential impact and its effect in the future. Data access statement: Data from the Austrian Stroke Unit Registry can only be accessed by the employed statistician (DM), access inquiries have to be addressed to the registry’s academic review board.
Mineral exploration in biogeochemistry is related to the detection of anomalies in soil, which is driven by many factors and thus a complex problem. Mikšová, Rieser, and Filzmoser (2019b) have ...introduced a method for the identification of spatial patterns with increased element concentrations in samples along a linear sampling transect. This procedure is based on fitting Generalized Additive Models (GAMs) to the concentration data, and computing a curvature measure from the pairwise log-ratios of these fits. The higher the curvature, the more likely one or both elements of the pair indicate local mineralization. This method is applied on two geochemical data sets which have been collected specifically for the purpose of mineral exploration. The aim is to test the technique for its ability to identify pathfinder elements to detect mineralized zones, and to verify whether the method can indicate which sampling material is best suited for this purpose.
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