A study of the omega equation for diagnosing vertical motions at ocean fronts

Estimation of vertical velocity is a key issue for understanding ocean physics and transport of biogeochemical tracers. We examine the accuracy of estimating vertical velocity in fronts with the omega equation. The diagnostic performance of the omega equation is evaluated by using vertical velocities obtained from simulation of frontal instabilities in a primitive equation model as a reference. We use two traditional quasigeostrophic methods in which the flow is either a geostrophic flow computed from density or a nondivergent flow derived from vorticity and also test two new formulations: a quasigeostrophic method using the total flow field and the semigeostrophic omega equation. Results show that all four formulations correctly diagnose the vertical velocity pattern. However, estimates provided by the traditional quasigeostrophic formulations have systematic bias. In contrast, the two new techniques, which are practically equivalent, produce unbiased vertical velocity diagnostic at fronts. These results point out the importance of including higher order dynamics than quasigeostrophy to take into account the ageostrophic advection in the front. Since adequate filtering of ADCP data is not yet available to obtain a suitable total flow, the semigeostrophic omega equation is proposed as the most valuable tool to compute vertical velocities from high resolution density measurements

Toward the predictability of meteotsunamis in the Balearic Sea using regional nested atmosphere and ocean models

Meteotsunamis are oceanic waves that possess tsunami‐like characteristics but are meteorological in origin. In the western Mediterranean, travelling atmospheric pressure oscillations generate these long oceanic surface waves that can become amplified and produce strong seiche oscillations inside harbors. We analyze a June 2006 meteotsunami event in Ciutadella harbor (Menorca Island, Spain), studying numerically the phenomenon during its full life cycle, from the early atmospheric stages to the atmosphere‐ocean resonant phase and the final highly amplified harbor oscillation. The Weather Research Forecast (WRF) atmospheric model adequately reproduces the development of a convective nucleus and also reproduces the induced atmospheric pressure oscillations moving at a speed of 27 m/s. The oceanic response is studied using the Regional Ocean Modeling System (ROMS), forced by the WRF pressure field. It shows an inverse barometer wave front in the open ocean progressively amplified through resonant interactions in the different shelf and coastal regions. The predictive capability of this new WRF/ROMS modeling approach is then discussed.This work has been partially funded by COOL (CTM2006‐12072/MAR), ECOOP (CTM2007‐31006E) and SOCIB Modeling Facility whose support is gratefully acknowledged

Role of high mobility group box protein 1 (HMGB1) in peripheral blood from patients with multiple sclerosis

Altres ajuts: The authors thank the 'Red Española de Esclerosis Múltiple (REEM)' sponsored by the 'Fondo de Investigación Sanitaria' (FIS), Ministry of Science and Innovation, Spain, and the 'Ajuts per donar Suport als Grups de Recerca de Catalunya,' sponsored by the 'Agència de Gestió d'Ajuts Universitaris i de Recerca' (AGAUR), Generalitat de Catalunya, Spain.High mobility group box protein 1 (HMGB1) is a transcriptional regulator that is receiving increasing attention in autoimmune disorders including multiple sclerosis (MS). Here, we investigated the role of HMGB1 in the peripheral blood compartment from MS patients. HMGB1 mRNA expression levels were determined by PCR in peripheral blood mononuclear cells (PBMC) of 29 healthy controls and 57 untreated MS patients (26 with relapsing-remitting MS - RRMS, 13 with secondary progressive MS - SPMS, and 18 with primary progressive MS - PPMS). HMGB1 protein levels were measured by ELISA in serum samples from 18 HC and 37 untreated MS patients (13 with RRMS, 14 with SPMS, and 10 with PPMS). HMGB1 expression levels were increased in PBMC from the whole MS group compared with controls (P = 0.03). Further stratification of the MS group revealed higher expression levels in PBMC from patients with relapse-onset MS, and differences were statistically significant for RRMS patients compared with PPMS patients and controls (P = 4 × 10 −5 and P = 0.005, respectively) and also for SPMS patients compared with PPMS patients (P = 0.001). HMGB1 serum levels were increased in the whole MS group compared with controls (P = 2 × 10 −4). In MS clinical forms, the highest HMGB1 serum levels were observed in RRMS patients, and differences were statistically significant compared to PPMS patients (P = 5 × 10 −5), SPMS patients (P = 0.001), and controls (P = 0.001). These results point to a role of HMGB1 mRNA and protein levels as disease activity biomarkers to discriminate the more inflammatory relapse-onset MS forms, particularly RRMS, from the less inflammatory PPMS form of the disease. The online version of this article (doi:10.1186/s12974-015-0269-9) contains supplementary material, which is available to authorized users

Optic Nerve Topography in Multiple Sclerosis Diagnosis

To assess the added value of the optic nerve region (by using visual evoked potentials [VEPs]) to the current diagnostic criteria. From the Barcelona clinically isolated syndrome (CIS) cohort, patients with complete information to assess dissemination in space (DIS), the optic nerve region, and dissemination in time at baseline (n = 388) were selected. Modified DIS (modDIS) criteria were constructed by adding the optic nerve to the current DIS regions. The DIS and modDIS criteria were evaluated with univariable Cox proportional hazard regression analyses with the time to the second attack as the outcome. A subset of these patients who had at least 10 years of follow-up or a second attack occurring within 10 years (n = 151) were selected to assess the diagnostic performance. The analyses were also performed according to CIS topography (optic neuritis vs non-optic neuritis). The addition of the optic nerve as a fifth region improved the diagnostic performance by slightly increasing the accuracy (2017 DIS 75.5%, modDIS 78.1%) and the sensitivity (2017 DIS 79.2%, modDIS 82.3%) without lowering the specificity (2017 DIS 52.4%, modDIS 52.4%). When the analysis was conducted according to CIS topography, the modDIS criteria performed similarly in both optic neuritis and non-optic neuritis CIS. The addition of the optic nerve, assessed by VEP, as a fifth region in the current DIS criteria slightly improves the diagnostic performance because it increases sensitivity without losing specificity

The long-term outcomes of CIS patients in the Barcelona inception cohort : Looking back to recognize aggressive MS

Altres ajuts: This study has been funded by European Regional Development Fund and co-funded by Instituto Carlos III. It has also received support by a grant from Genzyme foundation (GENZYME-2015-01) granted to M.T. and from the 'Red Española de Esclerosis Múltiple (REEM)', which is sponsored by FIS, the Instituto de Salud Carlos III, the Ministry of Economy and Competitiveness in Spain, and the 'Ajuts per donar Suport als Grups de Recerca de Catalunya', which is sponsored by the 'Agència de Gestió d'Ajuts Universitaris i de Recerca' (AGAUR) of the Generalitat de Catalunya in Spain.To explore the long-term outcomes of patients with clinically isolated syndromes from the Barcelona cohort. We selected patients with a follow-up longer than 10 years to (1) estimate the risks of multiple sclerosis (MS) and disability accumulation according to the baseline number of T2 lesions and to compare treated versus untreated patients and early versus delayed treatment, and (2) to study baseline features of patients with aggressive MS (Expanded Disability Status Scale (EDSS) ⩾6.0 at 10 years). In all, 401 patients were included (mean follow-up of 14.4 (standard deviation of 2.9) years). A higher number of T2 lesions was associated with an earlier MS diagnosis and an earlier risk of irreversible disability. Early treatment was associated with a decreased risk of EDSS of 3.0: adjusted hazard ratio = 0.4, 95% confidence interval = (0.2, 0.7). Patients with aggressive MS differed in their baseline brain magnetic resonance images: The median (interquartile range) number of T2 lesions and contrast-enhancing lesions (CEL) was 71 (28-95) versus 7 (1-19) and 3 (1-24) versus 0 (0-1), respectively. The cut-offs that better classified patients with aggressive MS were 20 for T2 lesions and 2 for CEL. Although MS natural history is changing, a high lesion load at onset is helpful to identify patients at risk of presenting an aggressive MS

A proposed ecosystem-based management system for marine waters: linking the theory of environmental policy to the practice of environmental management

New coastal and marine management strategies have recently been developed in many countries and regions. From an ecosystem approach perspective, the aim of such strategies is the maintenance of ecosystem integrity while enabling the sustainable use of ecosystem goods and services. There is, however, a need for harmonized definitions and standardized processes to deal not only with the interjurisdictional and multidisciplinary complexities that are associated with such strategies but also with the extensive timelines and resources implicated in the planning and implementation of these strategies. The ecosystem-based management system proposed here is based on three pillars that facilitate the integration of an ecosystem approach to coastal and oceans policy development, regardless of the ecosystem or administrative scales. The managerial pillar is based on classical risk-management systems that incorporate environmental considerations and objectives within a continuous improvement cycle of adaptive management. The managerial pillar is supported by governance structures that provide oversight and thereby ensure that planning and implementation activities adhere to modern environmental principles. The information pillar ensures that data and scientific advice are based on current knowledge, and the participation pillar brings together communication and consultation requirements as indicated by the principles of the ecosystem approach

Management model, leadership and autonomy in Portuguese and Spanish public schools: a comparative analysis

The organisation of K-18 schools and the management function are similar in Portugal and Spain, although, in recent years, Portugal has surpassed Spain’s educational results. Based on the last international reports, this article compares the educational systems of both countries considering some variables related to the management model: (i) the general organisation of education in these stages, (ii) the characteristics of the teaching profession, including the process of recruitment and selection of teachers and principals, and (iii) the level of school autonomy and the type of management and leadership. Findings corroborated the existence of structural proximity in the governance of schools within the framework of a management model that is both centralized and participatory. However, there are differences in the permanency of educational laws, the duration of compulsory education, the grouping of schools, and the requirements to be a teacher. We conclude that the policies undertaken by Portugal to improve education (such as the extension of compulsory schooling, legislative stability, or the rethinking of the internal organization of schools) are succeeding and can serve as an example for Spain. Both countries could help principals become leaders for learning and improve their autonomy to favour changes in education.info:eu-repo/semantics/publishedVersio

Surface currents of the Ibiza Channel (October 2014)

In this document we describe a new application of DIVAnd (Data-Interpolating Variational Analysis, in n-dimensions) for high-frequency (HF) radar currents. DIVAnd is a tool to interpolate observations on a regular grid using the variational inverse method. We have extended DIVAnd to include additional dynamic constraints relevant to surface currents, including imposing a zero normal velocity at the coastline, imposing a low horizontal divergence of the surface currents, temporal coherence and simplified dynamics based on the Coriolis force and the possibility of including a surface pressure gradient. The impact of these constraints is evaluated by cross-validation using the HF radar surface current observations in the Ibiza Channel from the Balearic Islands Coastal Ocean Observing and Forecasting System (SOCIB). A small fraction of the radial current observations are set aside to validate the velocity reconstruction. The remaining radial currents from the two radar sites are combined to derive total surface currents using DIVAnd and then compared to the cross-validation data set and to drifter observations. The benefit of the dynamic constraints is shown relative to a variational interpolation without these dynamical constraints. The best results were obtained using the Coriolis force and the surface pressure gradient as a constraint which are able to improve the reconstruction from the Open-boundary Modal Analysis, a quite commonly used method to interpolate HF radar observations, once multiple time instances are considered together. This PiDoc is a summarized version of a paper in press at Ocean Dynamics (Barth et al, 2021)