Reactive mass transport modelling of a three-dimensional vertical fault zone with a finger-like convective flow regime

For a three-dimensional vertically-oriented fault zone, we consider the coupled effects of fluid flow, heat transfer and reactive mass transport, to investigate the patterns of fluid flow, temperature distribution, mineral alteration and chemically induced porosity changes. We show, analytically and numerically, that finger-like convection patterns can arise in a vertically-oriented fault zone. The onset and patterns of convective fluid flow are controlled by the Rayleigh number which is a function of the thermal properties of the fluid and the rock, the vertical temperature gradient, and the height and the permeability of the fault zone. Vigorous fluid flow causes low temperature gradients over a large region of the fault zone. In such a case, flow across lithological interfaces becomes the most important mechanism for the formation of sharp chemical reaction fronts. The degree of rock buffering, the extent and intensity of alteration, the alteration mineralogy and in some cases the formation of ore deposits are controlled by the magnitude of the flow velocity across these compositional interfaces in the rock. This indicates that alteration patterns along compositional boundaries in the rock may provide some insights into the convection pattern. The advective mass and heat exchanges between the fault zone and the wallrock depend on the permeability contrast between the fault zone and the wallrock. A high permeability contrast promotes focussed convective flow within the fault zone and diffusive exchange of heat and chemical reactants between the fault zone and the wallrock. However, a more gradual permeability change may lead to a regional-scale convective flow system where the flow pattern in the fault affects large-scale fluid flow, mass transport and chemical alteration in the wallrocks

Infrared regime of SU(2) with one adjoint Dirac flavor

SU(2) gauge theory with one Dirac flavor in the adjoint representation is investigated on a lattice. Initial results for the gluonic and mesonic spectrum, static potential from Wilson and Polyakov loops, and the anomalous dimension of the fermionic condensate from the Dirac mode number are presented. The results found are not consistent with conventional confining behavior, pointing instead tentatively towards a theory lying within or very near the onset of the conformal window, with the anomalous dimension of the fermionic condensate in the range 0.9≲γ∗≲0.95. The implications of our work for building a viable theory of strongly interacting dynamics beyond the standard model are discussed.

Challenges in the participatory assessment of sustainable management practices in dryland ecosystems under regime shifts

Regime shifts, defined as a radical and persistent reconfiguration of an ecosystem following a disturbance, have been acknowledged by scientists as a very important aspect of the dynamic of ecosystems. However, their consideration in land management planning remains marginal and limited to specific processes and systems. Current research focuses on mathematical modeling and statistical analysis of spatio-temporal data for specific environmental variables. These methods do not fulfill the needs of land managers, who are confronted with a multitude of processes and pressure types and require clear and simple strategies to prevent regime shift or to increase the resilience of their environment. The EU-FP7 CASCADE project is looking at regime shifts of dryland ecosystems in southern Europe and specifically focuses on rangeland and forest systems which are prone to various land degradation threats. One of the aims of the project is to evaluate the impact of different management practices on the dynamic of the environment in a participatory manner, including a multi-stakeholder evaluation of the state of the environment and of the management potential. To achieve this objective we have organized several stakeholder meetings and we have compiled a review of management practices using the WOCAT methodology, which enables merging scientific and land users knowledge. We highlight here the main challenges we have encountered in applying the notion of regime shift to real world socio-ecological systems and in translating related concepts such as tipping points, stable states, hysteresis and resilience to land managers, using concrete examples from CASCADE study sites. Secondly, we explore the advantages of including land users’ knowledge in the scientific understanding of regime shifts. Moreover, we discuss useful alternative concepts and lessons learnt that will allow us to build a participatory method for the assessment of resilient management practices in specific socio-ecological systems and to foster adaptive dryland management.

The relationship between leadership practices and a medication safety regime

Errors in healthcare are commonplace and have significant impact on mortality, morbidity, and costs. Other high-risk industries are credited with strong safety records. These successes are due in part to a strong, committed organizational culture and their leadership. A consistent pattern of effective leadership behaviors; creating change, establishing a vision and strategic actions, and enabling and inspiring the organization's members to act, is present in these high-risk industries. This research examined the relationship between leadership practices and a medication safety regime. The hypothesis is strong leadership practices have a positive relationship with the degree of sophistication of a medication safety program (safety performance). Leadership was used as a surrogate for organizational culture and was measured in this research through the Kouzes and Posner's Leadership Practices Inventory. The Institute of Medicine's 14 Selected Strategies to Improve Medication Safety was used to measure the development of a medication safety regime. Leadership practices towards safety were assessed by surveying 2,478 critical care Registered Nurses in the greater Houston area. A response rate of 19% was achieved. Thirteen hospitals participated in the medication safety regime assessment. Data from 386 RN respondents from 53 institutions provided an overall description of unit (ICU) and organization (hospital) leader's practices towards safety. There is some recognition of the medical error problem and that leaders exhibit moderate levels of leadership practices to promote safety. There were no differences noted in unit and hospital leaders' behaviors, with the exception that unit leaders promote change and enable staff to act more often than hospital leaders. There were no statistically significant relationships between overall leadership, or individual leadership practices and the organization's safety performance. There was a significant relationship between leadership and safety performance when other factors in organizational culture were considered. Teaching and Magnet hospitals also exhibited stronger behaviors towards safety. Organizational culture, as measured by academic affiliation and Magnet recognition, is strongly related to safety performance as measured by the degree of development of a medication safety regime. ^

Empirical Analysis of Credit Risk Regime Switching and Temporal Conditional Default Correlation in Credit Default Swap Valuation: The Market liquidity effect

In this paper, we extend the debate concerning Credit Default Swap valuation to include time varying correlation and co-variances. Traditional multi-variate techniques treat the correlations between covariates as constant over time; however, this view is not supported by the data. Secondly, since financial data does not follow a normal distribution because of its heavy tails, modeling the data using a Generalized Linear model (GLM) incorporating copulas emerge as a more robust technique over traditional approaches. This paper also includes an empirical analysis of the regime switching dynamics of credit risk in the presence of liquidity by following the general practice of assuming that credit and market risk follow a Markov process. The study was based on Credit Default Swap data obtained from Bloomberg that spanned the period January 1st 2004 to August 08th 2006. The empirical examination of the regime switching tendencies provided quantitative support to the anecdotal view that liquidity decreases as credit quality deteriorates. The analysis also examined the joint probability distribution of the credit risk determinants across credit quality through the use of a copula function which disaggregates the behavior embedded in the marginal gamma distributions, so as to isolate the level of dependence which is captured in the copula function. The results suggest that the time varying joint correlation matrix performed far superior as compared to the constant correlation matrix; the centerpiece of linear regression models.

OS Planos Municipais de Educaçao no Tocantins : Arqueologia dos processos de construçao e perspectivas de regime de colaboraçao e da gestao democrática

O trabalho apresenta resultados de pesquisa acerca das políticas de educaçao no Brasil, do princípio regime de colaboraçao e da gestao da educaçao, apresentando, neste momento, aspectos da trajetória sociopolítica da elaboraçao ou adequaçao dos Planos Municipais de Educaçao (PMEs), deflagrada em 2013 pelo MEC/SASE, com as possibilidades de efetivaçao do regime de colaboraçao e da gestao democrática. Sua abordagem é qualitativa, de caráter teórico-empírico e exploratório, abarcando a documentaçao relativa aos PMEs dos Municípios. No Tocantins, até o início do ano de 2014, um georreferenciamento demonstra que dos 139 Municípios, apenas seis elaboraram seus PMEs. Neste contexto, predomina a visao de administraçao municipal restrita às suas instituiçoes escolares e ao tempo de sua gestao, sem relaçao ou articulaçao com metas nacionais comuns com vistas à materializaçao do Sistema Nacional de Educaçao. Deste processo, destaca-se o significativo movimento sociopolítico em torno do planejamento da educaçao no século XXI, enfrentado o desafio de definir o objetivo comum da educaçao brasileira. Entretanto, há ideias que merecem ser investigadas, como a sua concepçao de gestao e planejamento e as formas de colaboraçao estabelecidas

OS Planos Municipais de Educaçao no Tocantins : Arqueologia dos processos de construçao e perspectivas de regime de colaboraçao e da gestao democrática

O trabalho apresenta resultados de pesquisa acerca das políticas de educaçao no Brasil, do princípio regime de colaboraçao e da gestao da educaçao, apresentando, neste momento, aspectos da trajetória sociopolítica da elaboraçao ou adequaçao dos Planos Municipais de Educaçao (PMEs), deflagrada em 2013 pelo MEC/SASE, com as possibilidades de efetivaçao do regime de colaboraçao e da gestao democrática. Sua abordagem é qualitativa, de caráter teórico-empírico e exploratório, abarcando a documentaçao relativa aos PMEs dos Municípios. No Tocantins, até o início do ano de 2014, um georreferenciamento demonstra que dos 139 Municípios, apenas seis elaboraram seus PMEs. Neste contexto, predomina a visao de administraçao municipal restrita às suas instituiçoes escolares e ao tempo de sua gestao, sem relaçao ou articulaçao com metas nacionais comuns com vistas à materializaçao do Sistema Nacional de Educaçao. Deste processo, destaca-se o significativo movimento sociopolítico em torno do planejamento da educaçao no século XXI, enfrentado o desafio de definir o objetivo comum da educaçao brasileira. Entretanto, há ideias que merecem ser investigadas, como a sua concepçao de gestao e planejamento e as formas de colaboraçao estabelecidas