99 research outputs found
Nota sobre les roques hipabissals de la Serra de Tramuntana de Mallorca: algunes característiques petrogràfiques y geoquímiques
Some diabase and more leucocratic dykes found in Mallorca demonstrate the existence of subvolcanic or hypoabyssal on this island. All these outcrops are always found inside the triassic materials, and and thus may be directly related to the upper triassic volcanism. Although some of the studied rocks have evident alkaline affinities (with ne and ol in the CIPW norm), others display greater diversity, from transitional (with ol and hy ) to subalkaline types (with hy and Q in the norm)
Las rocas hipoabisales hercinianas y tardi-hercinianas del sector centro-oriental del sinclinal de Llavorsí (Pirineo Central)
Los materiales silricos, devnicos que constituyen el sinclinal de Llavors (Pirineo central) estn atravesados por dos grupos principales de rocas gneas hipoabisales. El primer grupo esta formado por rocas de composicin bsica e intermedis afectadas por un metamorfismo herciniano de grado muy bajo y forman parte, por tanto, de un episodio magmtico bsico anterior a las deformaciones principales hercinianas. Las transformaciones secundarias sufridas por estas rocas impiden deducir, apartir del estudio de 10s elementos mayores, su pertenencia a una serie ignea determinada si bien pueden distinguirse claramente dos asociaciones con distintas relaciones Mg/Fe. El segundo grupo, claramente postectnico, est constituido nicamente por rocas cidas (felsitas y prfidos granticos y granodioriticos), relacionadas aparentemente con el plutonismo calcoalcalino tardi-herciniano
A chemical approximation to the modal QAPF and normative Q' (F')-ANOR classification of the igneous rocks based on their SiO2-CaO-K2O content
Magmas can form plutonic or volcanic rocks of the same chemical composition. The modal composition of the plutonic rocks can be quantified but in the case of volcanic rocks this is not always possible, because of its aphanitic texture and presence of glass. These characteristics prevent a mineralogical classification in equivalent diagrams for both types of rocks. To resolve this problem, the IUGS recommends the use of chemical TAS diagram in cases where obtaining the modal composition is not possible, in an attempt to adjust its nomenclature to that represented in the QAPF modal diagram. A best approximation is obtained with the normative diagram Q'(F')-ANOR in which the anorthite and the orthoclase are used as a discriminating factor. In this work, the chemical SiO2-100·CaO/(CaO+K2O) diagram is presented, which largely reproduces the aforementioned normative classification but in a simplified form since it uses only three discriminating chemical components (SiO2, CaO and K2O). The delimitation and nomenclature of the fields has been undertaken empirically using as an example the normative diagram and plotting the analyses of typical igneous rocks. The approximate limit of silica saturation has been drawn as a straight line joining the feldspathic compositions, between orthoclase and anorthit
Comparative study of the classification of plutonic and volcanic rocks using the normative Q' (F')-ANOR and chemical SiO2-100·CaO/(CaO+K2O) diagrams
To obtain a classification of igneous rocks, compatible with the QAPF classification, in the absence of modal analyses, a chemical diagram using the same discriminating elements as the Q'(F')-ANOR normative diagram has been proposed. These elements, Si, Ca and K, are essential constituents of quartz, feldspars and feldspathoids. The different proportions between these minerals are the basis of the QAPF modal classification but also those of the normative classification Q'(F')-ANOR. The chemical diagram SiO2100·CaO/(CaO+K2O) uses these same elements but with the important difference that they are treated as independent variables. This characteristic allows igneous rocks to be classified with a nomenclature equivalent to that obtained by modal analyses, using only Si, Ca and K analytical data. The plotting of a set of representative plutonic and volcanic rocks reveals a remarkable concordance between both diagrams. However, some discrepancies and overlaps occur in the subsaturated fields due to the inability of the method to determine whether the lower silica content is due to the presence of olivine or feldspathoids. The samples selected belong to igneous series from diverse geotectonic areas , thus helping to evaluate the results in a global context
Procesos de mezcla incompleta entre un magma granodiorítico y una intrusión diorítica parcialmente consolidada en Llafranc (Cordillera Litoral Catalana, NE de la Península Ibérica)
La presencia de rocas intrusivas heterogéneas originadas por mezcla de magmas es frecuente en distintos ámbitos geológicos. En este trabajo se estudian los posibles procesos que han dado lugar a la formación de las cuarzodioritas hercinianas de Llafranc. La morfología de los contactos entre las zonas granodioríticas y cuarzodioríticas y la distribución de los fenocristales sugieren que se produjo una inyección de magma granodiorítico, en una intrusión cuarzodiorítica parcialmente consolidada pero aún con fluidez suficiente para mezclarse de forma limitada. La evolución conjunta de los dos magmas a temperaturas decrecientes genera una secuencia en la tipología de los contactos que empieza con contactos difusos curvilíneos, con marcado intercambio de fases minerales, y acaba con contactos netos, rectilíneos sin intercambio cristalino apreciabl
Roques ígnies i magmes
En el document s'introdueixen els conceptes bàsics sobre la definició i l'origen de les roques ígnies i els magmes i la seva ubicació espacial i temporal
Las hornblenditas,gabros y dioritas del Macizo del Montnegre (Barcelona, Cordilleras costero catalanas)
En relación con los granitos tardihercínicos calcoalcalinos del Macizo del Montnegre aparecen rocas ultrabásicas-básicas a intermedias. Las más básicas son hornblenditas olivínicas, con espinela, clinopiroxeno, ortopiroxeno, anfíboles de varios tipos y flogopita. Hay además melagabros-gabros hornbléndicos y leucogabros, estos últimos con anfíbol minoritario. Las rocas más ácidas son cuarzodioritas y cuarzomonzodioritas biotítico-hornbléndicas, con cristales relictos de clinopiroxeno y ortopiroxeno. El contenido máximo en anortita de la plagioclasa en las dioritas es tan alto como en los gabros. Toda la asociación muestra una evolución típicamente calcoalcalina, pero las hornblenditas y algunos gabros podrían haberse formado a partir de diferentes tipos de magmas básicos. Las cuarzodioritas serían rocas híbridas, con participación de un magma más básico y otro más ácido. El primero estaría saturado en clinopiroxeno y ortopiroxeno, además de en plagioclasa de composición bitownita, y el otro magma sería más ácido
Primely generated refinement monoids
We extend both Dobbertin's characterization of primely generated regular refinement monoids and Pierce's characterization of primitive monoids to general primely generated refinement monoids.The first-named author was partially supported by DGI MINECO
MTM2011-28992-C02-01, by FEDER UNAB10-4E-378 "Una manera de hacer Europa", and by the Comissionat per Universitats i Recerca de la Generalitat de Catalunya. The second-named author was partially supported by the DGI and European Regional Development Fund, jointly, through Project MTM2011-28992-C02-02, and by PAI III grants FQM-298 and P11-FQM-7156 of the Junta de Andalucía
Accuracy of online survey assessment of mental disorders and suicidal thoughts and behaviors in Spanish university students. Results of the WHO World Mental Health- International College Student initiative
Objective
To assess the accuracy of WMH-ICS online screening scales for evaluating four common mental disorders (Major Depressive Episode[MDE], Mania/Hypomania[M/H], Panic Disorder[PD], Generalized Anxiety Disorder[GAD]) and suicidal thoughts and behaviors[STB] used in the UNIVERSAL project.
Methods
Clinical diagnostic reappraisal was carried out on a subsample of the UNIVERSAL project, a longitudinal online survey of first year Spanish students (18-24 years old), part of the WHO World Mental Health-International College Student (WMH-ICS) initiative. Lifetime and 12month prevalence of MDE, M/H, PD, GAD and STB were assessed with the Composite International Diagnostic Interview-Screening Scales [CIDI-SC], the Self-Injurious Thoughts and Behaviors Interview [SITBI] and the Columbia-Suicide Severity Rating Scale [C-SSRS]. Trained clinical psychologists, blinded to responses in the initial survey, administered via telephone the Mini-International Neuropsychiatric Interview [MINI]. Measures of diagnostic accuracy and McNemar chi(2) test were calculated. Sensitivity analyses were conducted to maximize diagnostic capacity.
Results
A total of 287 students were included in the clinical reappraisal study. For 12-month and lifetime mood disorders, sensitivity/specificity were 67%/88.6% and 65%/73.3%, respectively. For 12-month and lifetime anxiety disorders, these were 76.8%/86.5% and 59.6%/71.1%, and for 12-month and lifetime STB, 75.9%/94.8% and 87.2%/86.3%. For 12-month and lifetime mood disorders, anxiety disorders and STB, positive predictive values were in the range of 18.1-55.1% and negative predictive values 90.2-99.0%; likelihood ratios positive were in the range of 2.1-14.6 and likelihood ratios negative 0.1-0.6. All outcomes showed adequate areas under the curve [AUCs] (AUC> 0.7), except M/H and PD (AUC = 0.6). Post hoc analyses to select optimal diagnostic thresholds led to improved concordance for all diagnoses (AUCs> 0.8).
Conclusion
The WMS-ICS survey showed reasonable concordance with the MINI telephone interviews performed by mental health professionals, when utilizing optimized cut-off scores. The current study provides initial evidence that the WMS-ICS survey might be useful for screening purposes
A multiple stakeholder multicriteria decision analysis in diabetic macular edema management: the MULTIDEX‑EMD study
Background The clinical and economic management of retinal diseases has become more complex following the introduction of new intravitreal treatments. Multicriteria decision analysis (MCDA) ofers the potential to overcome the challenges
associated with traditional decision-making tools.
Objectives A MCDA to determine the most relevant criteria to decision-making in the management of diabetic macular edema (DME) based on the perspectives of multiple stakeholders in Spain was developed. This MCDA was termed the MULTIDEX-EMD study.
Methods Nineteen stakeholders (7 physicians, 4 pharmacists, 5 health authorities and health management experts, 1 psychologist, and 2 patient representatives) participated in this three-phase project. In phase A, an advisory board defned all of the criteria that could infuence DME treatment decision-making. These criteria were then screened using a discrete choice experiment (DCE) (phase B). Next, a multinomial logit model was ftted by applying the backward elimination algorithm (relevant criteria: p value<0.05). Finally, the results were discussed in a deliberative process (phase C).
Results Thirty-one criteria were initially defned (phase A) and grouped into 5 categories: efcacy/efectiveness, safety, organizational and economic impact, patient-reported outcomes, and other therapeutic features. The DCE results (phase B) showed that 10 criteria were relevant to the decision-making process for a 50- to 65-year-old DME patient: mean change in best corrected visual acuity (p value<0.001), percentage of patients with an improvement of ≥15 letters (p value<0.001), efect duration per administration (p value=0.008), retinal detachment (p value<0.001), endophthalmitis (p value=0.012), myocardial infarction (p value<0.001), intravitreal hemorrhage (p value=0.021), annual treatment cost per patient (p value=0.001), health-related quality of life (HRQoL) (p value=0.004), and disability level (p value=0.021).
Conclusions From a multi-stakeholder perspective, the selection of an appropriate treatment for DME patients should guarantee patient safety and maximize the visual acuity improvement and treatment efect duration. It should also contribute to system sustainability by being afordable, it should have a positive impact on HRQoL, and it should prevent disability
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