Forward-looking versus recursive-dynamic modeling in climate policy analysis: A comparison

This paper develops a multi-regional general equilibrium model for climate policy analysis based on the latest version of the MIT Emissions Prediction and Policy Analysis (EPPA) model. We develop two versions so that we can solve the model either as a fully inter-temporal optimization problem (forward-looking, perfect foresight) or recursively. The standard EPPA model on which these models are based is solved recursively, and it is necessary to simplify some aspects of it to make inter-temporal solution possible. The forward-looking capability allows one to better address economic and policy issues such as borrowing and banking of GHG allowances, efficiency implications of environmental tax recycling, endogenous depletion of fossil resources, international capital flows, and optimal emissions abatement paths among others. To evaluate the solution approaches, we benchmark each version to the same macroeconomic path, and then compare the behavior of the two versions under a climate policy that restricts greenhouse gas emissions. We find that the energy sector and CO(2) price behavior are similar in both versions (in the recursive version of the model we force the inter-temporal theoretical efficiency result that abatement through time should be allocated such that the CO(2) price rises at the interest rate.) The main difference that arises is that the macroeconomic costs are substantially lower in the forward-looking version of the model, since it allows consumption shifting as an additional avenue of adjustment to the policy. On the other hand, the simplifications required for solving the model as an optimization problem, such as dropping the full vintaging of the capital stock and fewer explicit technological options, likely have effects on the results. Moreover, inter-temporal optimization with perfect foresight poorly represents the real economy where agents face high levels of uncertainty that likely lead to higher costs than if they knew the future with certainty. We conclude that while the forward-looking model has value for some problems, the recursive model produces similar behavior in the energy sector and provides greater flexibility in the details of the system that can be represented. (C) 2009 Elsevier B.V. All rights reserved.

The Development of Science Education Research in Brazil and Contributions from the History and Philosophy of Science

Over the last 50 years a new research area, science education research, has arisen and undergone singular development worldwide. In the specific case of Brazil, research in science education first appeared systematically 40 years ago, as a consequence of an overall renovation in the field of science education. This evolution was also related to the political events taking place in the country. We will use the theoretical work of Rene Kaes on the development of groups and institutions as a basis for our discussion of the most important aspects that have helped the area of science education research develop into an institution and kept it operating as such. The growth of this area of research can be divided into three phases: The first was related to its beginning and early configurations; the second consisted of a process of consolidation of this institution; and the third consists of more recent developments, characterised by a multiplicity of research lines and corresponding challenges to be faced. In particular, we will analyse the special contributions to this study gleaned from the field known as the history and philosophy of science.

Participatory assessment of rural livelihoods in the Central Highlands of Vietnam

There is a need for improved monitoring and evaluation (M&E) of participatory research with smallholder farmers, in particular to help differentiate between different types of farm household with different needs. This paper reports some of the results of a study to develop participatory M&E tools for the Forages for Smallholders Project in Southeast Asia, focusing on an upland commune in central Vietnam with a highly diverse crop-livestock system. Participatory rural appraisal techniques were used within a rural livelihoods framework to assess the differing livelihoods of poor, average, and better-off households. There were found to be marked differences between households, particularly in human resources, landholdings, and cattle numbers, affecting the livelihood strategies pursued. The improved understanding of livelihood strategies was gained in a cost-effective way and could be readily used by project participants to monitor the impacts of the introduced forages within the commune, enabling better focusing of the participatory research process on the needs and circumstances of poor farmers. (C) 2003 Elsevier Ltd. All rights reserved.

Fragmentation of a Neotropical migratory fish population by a century-old dam

Loss of connectivity in impounded rivers is among the impacts imposed by dams, and mitigation measures such as fish passages might not accomplish their purpose of reestablishing an efficient bi-directional gene flow in the fish populations affected. As a consequence, fish populations remain fragmented, and a new interpopulational structure may develop, with increased risk of reduced genetic diversity and stochastic extinction. In order to evaluate the effects of the Gavio Peixoto Dam, which was constructed almost a century ago on the Jacar,-Gua double dagger u River in the Upper Parana River basin, Brazil, a comparative morphometric study was undertaken on the populations of the Neotropical migratory characid fish Salminus hilarii living up- and downstream of this dam. Population dynamics, spatial segregation, and habitat use by different age classes were monitored for 2 years. We found that segregation caused by the dam and long periods with no efficient connection by fish passages have led to fragmentation and interpopulational structuring of S. hilarii, as revealed by canonical variable analysis of morphometric features. The fish populations occupying the up- and downstream sections have succeeded in performing short-distance reproductive migrations in the main river and tributaries, have found suitable habitats for completing their life cycle, and have been able to maintain distinct small-sized populations so far.

ICRAM (the International Campaign to Revitalise Academic Medicine): Agenda setting

Following die launch by the BMJ and others of the campaign to promote academic medicine, a working party of 20 medical academics from all over the world was convened to develop a plan of action.

In Vitro Antifungal Activity and Toxicity of Itraconazole in DMSA-PLGA Nanoparticles

Itraconazole (ITZ) is a drug used to treat various fungal infections and may cause side effects. The aim of this study was to develop and evaluate the in vitro activity of DMSA-PLGA nanoparticles loaded with ITZ against Paracoccidioides brasiliensis, as well as their cytotoxicity. Nanoparticles were prepared using the emulsification-evaporation technique and characterized by their encapsulation efficiency, morphology (TEM), size (Nanosight) and charge (zeta potential). Antifungal efficacy in P brasiliensis was determined by minimal inhibition concentration (MIC), and cytotoxicity using MU assay. ITZ was effectively incorporated in the PLGA-DMSA nanoparticles with a loading efficiency of 72.8 +/- 3.50%. The shape was round with a solid polymeric structure, and a size distribution of 174 +/- 86 nm (Average +/- SD). The particles were negatively charged. ITZ-NANO presented antifungal inhibition (MIC = 6.25 ug/mL) against P brasiliensis and showed lower in vitro cytotoxicity than free drug (ITZ).

Lipid microspheres loaded with antigenic membrane proteins of the Leishmania amazonensis as a potential biotechnology application

Lipid microspheres (LM) are excellent drug delivery or vaccines adjuvant systems and are relatively stable. The aim of this work is to develop and characterize a system that is able to encapsulate and present antigenic membrane proteins from Leishmania amazonensis. Membrane proteins are important for vaccine`s formulation because these proteins come in contact with the host cell first, triggering the cell mediated immune response. This is a useful tool to avoid or inactivate the parasite invasion. The LM are constituted by soybean oil (SO), dipalmitoylphosphatidilcholine (DPPC), cholesterol and solubilized protein extract (SPE). The particles formed presented an average diameter of 200 run, low polydispersion and good stability for a period of 30 days, according to dynamic light scattering assays. Isopycnic density gradient centrifugation of LM-protein showed that proteins and lipids floated in the sucrose gradient (5-50%w/v) suggesting that the LM-protein preparation was homogeneous and that the proteins are interacting with the system. The results show that 85% of SPE proteins were encapsulated in the LM. Studies of cellular viability of murine peritoneal macrophages show that our system does not present cytotoxic effect for the macrophages and still stimulates their NO production (which makes its application as a vaccine adjuvant possible). LM-protein loaded with antigenic membrane proteins from L. amazonensis seems to be a promising vaccine system for immunization against leishmaniasis. (C) 2009 Elsevier Inc. All rights reserved.

Cited2 is required both for heart morphogenesis and establishment of the left-right axis in mouse development

Establishment of the left-right axis is a fundamental process of vertebrate embryogenesis. Failure to develop left-right asymmetry leads to incorrect positioning and morphogenesis of numerous internal organs, and is proposed to underlie the etiology of several common cardiac malformations. The transcriptional modulator Cited2 is essential for embryonic development: Cited2-null embryos die during gestation with profound developmental abnormalities, including cardiac malformations, exencephaly and adrenal agenesis. Cited2 is also required for normal establishment of the left-right axis; we demonstrate that abnormal heart looping and right atrial and pulmonary isomerism are consistent features of the left-right-patterning defect. We show by gene expression analysis that Cited2 acts upstream of Nodal, Lefty2 and Pitx2 in the lateral mesoderm, and of Lefty1 in the presumptive floor plate. Although abnormal left-right patterning has a major impact on the cardiac phenotype in Cited2-null embryos, laterality defects are only observed in a proportion of these embryos. We have therefore used a combination of high-resolution imaging and three-dimensional (3D) modeling to systematically document the full spectrum of Cited2-associated cardiac defects. Previous studies have focused on the role of Cited2 in cardiac neural crest cell development, as Cited2 can bind the transcription factor Tfap2, and thus affect the expression of Erbb3 in neural crest cells. However, we have identified Cited2-associated cardiac defects that cannot be explained by laterality or neural crest abnormalities. In particular, muscular ventricular septal defects and reduced cell density in the atrioventricular (AV) endocardial cushions are evident in Cited2-null embryos. As we found that Cited2 expression tightly correlated with these sites, we believe that Cited2 plays a direct role in development of the AV canal and cardiac septa. We therefore propose that, in addition to the previously described reduction of cardiac neural crest cells, two other distinct mechanisms contribute to the spectrum of complex cardiac defects in Cited2-null mice; disruption of normal left-right patterning and direct loss of Cited2 expression in cardiac tissues.

Two-dimensional approximation for tidal dynamics in coastal aquifers: Capillarity correction

Most previous investigations on tide-induced watertable fluctuations in coastal aquifers have been based on one-dimensional models that describe the processes in the cross-shore direction alone, assuming negligible along-shore variability. A recent study proposed a two-dimensional approximation for tide-induced watertable fluctuations that took into account coastline variations. Here, we further develop this approximation in two ways, by extending the approximation to second order and by taking into account capillary effects. Our results demonstrate that both effects can markedly influence watertable fluctuations. In particular, with the first-order approximation, the local damping rate of the tidal signal could be subject to sizable errors.

Quantum analysis of the nondegenerate optical parametric oscillator with injected signal

In this paper we study the nondegenerate optical parametric oscillator with injected signal, both analytically and numerically. We develop a perturbation approach which allows us to find approximate analytical solutions, starting from the full equations of motion in the positive-P representation. We demonstrate the regimes of validity of our approximations via comparison with the full stochastic results. We find that, with reasonably low levels of injected signal, the system allows for demonstrations of quantum entanglement and the Einstein-Podolsky-Rosen paradox. In contrast to the normal optical parametric oscillator operating below threshold, these features are demonstrated with relatively intense fields.

Globalizing policy sociology in education: Working with Bourdieu

This paper uses Bourdieu to develop theorizing about policy processes in education and to extend the policy cycle approach in a time of globalization. Use is made of Bourdieu's concept of social field and the argument is sustained that in the context of globalization the field of educational policy has reduced autonomy, with enhanced cross-field effects in educational policy production, particularly from the fields of the economy and journalism. Given the social rather than geographical character of Bourdieu's concept of social fields, it is also argued that the concept can be, and indeed has to be, stretched beyond the nation to take account of the emergent global policy field in education. Utilizing Bourdieu's late work on the globalization of the economy through neo-liberal politics, we argue that a non-reified account of the emergent global educational policy field can be provided.

An evaluation of the evidence for linkages between mangroves and fisheries: A synthesis of the literature and identification of research directions

There is a widely held paradigm that mangroves are critical for sustaining production in coastal fisheries through their role as important nursery areas for fisheries species. This paradigm frequently forms the basis for important management decisions on habitat conservation and restoration of mangroves and other coastal wetlands. This paper reviews the current status of the paradigm and synthesises the information on the processes underlying these potential links. In the past, the paradigm has been supported by studies identifying correlations between the areal and linear extent of mangroves and fisheries catch. This paper goes beyond the correlative approach to develop a new framework on which future evaluations can be based. First, the review identifies what type of marine animals are using mangroves and at what life stages. These species can be categorised as estuarine residents, marine-estuarine species and marine stragglers. The marine-estuarine category includes many commercial species that use mangrove habitats as nurseries. The second stage is to determine why these species are using mangroves as nurseries. The three main proposals are that mangroves provide a refuge from predators, high levels of nutrients and shelter from physical disturbances. The recognition of the important attributes of mangrove nurseries then allows an evaluation of how changes in mangroves will affect the associated fauna. Surprisingly few studies have addressed this question. Consequently, it is difficult to predict how changes in any of these mangrove attributes would affect the faunal communities within them and, ultimately, influence the fisheries associated with them. From the information available, it seems likely that reductions in mangrove habitat complexity would reduce the biodiversity and abundance of the associated fauna, and these changes have the potential to cause cascading effects at higher trophic levels with possible consequences for fisheries. Finally, there is a discussion of the data that are currently available on mangrove distribution and fisheries catch, the limitations of these data and how best to use the data to understand mangrove-fisheries links and, ultimately, to optimise habitat and fisheries management. Examples are drawn from two relatively data-rich regions, Moreton Bay (Australia) and Western Peninsular Malaysia, to illustrate the data needs and research requirements for investigating the mangrove-fisheries paradigm. Having reliable and accurate data at appropriate spatial and temporal scales is crucial for mangrove-fisheries investigations. Recommendations are made for improvements to data collection methods that would meet these important criteria. This review provides a framework on which to base future investigations of mangrove-fisheries links, based on an understanding of the underlying processes and the need for rigorous data collection. Without this information, the understanding of the relationship between mangroves and fisheries will remain limited. Future investigations of mangrove-fisheries links must take this into account in order to have a good ecological basis and to provide better information and understanding to both fisheries and conservation managers.

Transgenic expression of a viral oncoprotein exclusively in K14(+) epithelial cells results in peripheral but not central CD8 T cell tolerance

The role of thymic versus peripheral epithelial cells in the negative selection of the peptide-specific CD8 T cell repertoire is still largely unresolved. We have generated TCRb chain transgenic mice in which 20–35% of peripheral CD8 T cells recognize an epitope from a viral, nuclear oncoprotein (human papillomavirus type 16 E7) in the context ofMHC class I, H-2Db. When T cells from these transgenic mice develop through the thymus of a second transgenic mouse expressing E7 from a keratin 14 promoter, no major perturbation to thymic T cell development is observed over a 7 month period. In contrast, peripheral CD8 T cell responses in these same mice (E7TCRxK14E7 double transgenic) become reduced over time. This data suggests that peripheral tolerance mechanisms predominate over thymic negative selection in controlling CD8 T cell responses to this epithelial, nuclear oncoprotein.

Defective NF-kappaB Activation in Response to LPS in Type 1 Diabetes Dendritic Cells

Dendritic cells (DC) are the potent antigen presenting cells which modulate T cell responses to self or non-self antigens. DC play a significant role in the pathogenesis of autoimmune diseases, inflammation and infection, but also in the maintenance of tolerance. NF-kappaB, particularly RelB is a crucial pathway for myeloid DC differentiation and functional maturation. While the current paradigm is that mature, nuclear RelB+ DC prime T cells for immunity/autoimmunity and immature DC for tolerance, RelB-deficient mice paradoxically develop generalised systemic autoimmune inflammatory disease with myelopoiesis and splenomegaly. Previous studies suggested abnormal DC differentiation in healthy relatives of type 1 diabetes (t1dm) patients. Therefore, we compared NF- kB activation in monocyte-derived DC from t1dm and non-t1dm controls in response to LPS. While resting DC appeared normal, DC from 6 out of 7 t1dm patients but no t2dm or rheumatoid arthritis patients failed to translocate NF- kB subunits to the nucleus in response to LPS, along with a failure to up-regulate expression of cell surface CD40 and MHC class I. NF- kB subunit mRNA increased normally in t1dm DC after LPS. Both the classical or non-canonical NF- kB pathways were affected as both TNF-a and CD40 stimulation led to a similarly abnormal NF- kB response. In contrast, expression of phosphorylated p38 MAPK and pro-inflammatory cytokine production was intact. These abnormalities in NF- kB activation appear to be generally and specifically applicable at a post-translational level in t1dm, and have the capacity to profoundly influence immunoregulation in affected individuals.

Transfer of Cholesterol and Other Lipids From a Lipid Nanoemulsion to High-density Lipoprotein in Heart Transplant Patients

Background: Beyond the first year after a heart transplant (HT) procedure, patients often develop dyslipidemias, which may be implicated in the genesis of transplant coronary heart disease. High-density lipoprotein (HDL) has a several anti-atherogenic properties, but the status of HDL in HT patients is still controversial. Nonetheless, determination of HDL cholesterol concentration is not sufficient for evaluation of the overall HDL protective role. In this study, a fundamental functional property of HDL, the ability to simultaneously receive the major lipid classes, was tested in HT patients. Methods: Twenty HT patients and 20 healthy normolipidemic subjects paired for gender, age and body mass index were studied. Blood samples were collected after 12-hour fasting for determination of plasma lipids, glucose, paraxonase I (PON 1) activity, HDL diameter and transfer of labeled lipids from an artificial nanoemulsion to HDL. Results: Plasma triglycerides (159 +/- 63 vs 94 +/- 35 mg/dl) and glucose (104 +/- 20 vs 86 +/- 10 mg/dl) were greater in HT patients than in control subjects. HDL cholesterol was lower and HDL diameter was smaller in the HT group (HDL cholesterol: 44 +/- 11 vs 55 +/- 15 mg/dl; HDL diameter: 8.8 +/- 0.6 vs 9.0 +/- 1.2 nm). PON 1 activity did not differ (87 +/- 47 vs 75 +/- 37 nmol/min/ml). The transfer rates of free cholesterol and cholesteryl esters were diminished in HT patients (HT: 8.4 +/- 1.2% and 3.8 +/- 0.6%; controls: 9.7 +/- 1.9% and 4.7 +/- 1.2%, respectively). Conclusions: The transfer of free cholesterol and cholesteryl esters to HDL is diminished in HT patients; disturbance in the ability of HDL to receive lipids may affect the anti-atherogenic properties of the lipoprotein. J Heart Lung Transplant 2009;28:1075-80. Copyright (C) 2009 by the International Society for Heart and Lung Transplantation.