Using Emissions Trading to Regulate U.S. Greenhouse Gas Emissions: An Overview of Policy Design and Implementation Issues

In Kyoto in 1997, the US government agreed that between 2008 and 2012 it would limit average annual emissions of greenhouse gases (GHGs) to seven percent below 1990 levels. As participants in the climate policy debate consider various means by which limits on US GHG emissions might be undertaken in the wake of the Kyoto agreement, there is considerable interest but also some confusion about how a GHG trading program could be organized and operated in practice. In this paper we address several aspects of policy design for a US system, such as who and what is covered by regulation, the organization of the trading system, how carbon permits are allocated, and how a system could be initiated and changed over time. The paper synthesizes existing analyses and adds new insights concerning uncertainty, intertemporal consistency, market institutions, and interactions with the tax system. Our fundamental conclusion is that a domestic "cap-and-trade" system with homogeneous permits applied to control flows of fossil fuels "upstream" in the energy system (along with selective inclusion of other gases and CO2 "sinks"), with permits auctioned periodically by the government, has the most appeal of different trading systems on efficiency and distributional grounds, though it may suffer politically because of its close resemblance to a carbon tax. We identify auction mechanisms that appear to be feasible and efficient for carbon permit allocation. We further argue that while the private sector should bear the "external" risk of changes in total permit availability as a consequence of modifications in international agreements, and that an auctioned upstream program provides more protection against the "internal" risk of efficiency-reducing opportunism by government regulators than other trading mechanisms.

Geometry shapes evolution of early multicellularity

Organisms have increased in complexity through a series of major evolutionary transitions, in which formerly autonomous entities become parts of a novel higher-level entity. One intriguing feature of the higher-level entity after some major transitions is a division of reproductive labor among its lower-level units. Although it can have clear benefits once established, it is unknown how such reproductive division of labor originates. We consider a recent evolution experiment on the yeast Saccharomyces cerevisiae as a unique platform to address the issue of reproductive differentiation during an evolutionary transition in individuality. In the experiment, independent yeast lineages evolved a multicellular "snowflake-like'' cluster form in response to gravity selection. Shortly after the evolution of clusters, the yeast evolved higher rates of cell death. While cell death enables clusters to split apart and form new groups, it also reduces their performance in the face of gravity selection. To understand the selective value of increased cell death, we create a mathematical model of the cellular arrangement within snowflake yeast clusters. The model reveals that the mechanism of cell death and the geometry of the snowflake interact in complex, evolutionarily important ways. We find that the organization of snowflake yeast imposes powerful limitations on the available space for new cell growth. By dying more frequently, cells in clusters avoid encountering space limitations, and, paradoxically, reach higher numbers. In addition, selection for particular group sizes can explain the increased rate of apoptosis both in terms of total cell number and total numbers of collectives. Thus, by considering the geometry of a primitive multicellular organism we can gain insight into the initial emergence of reproductive division of labor during an evolutionary transition in individuality.Comment: 7 figure

Comparisons of crop yields using semi-organic and inorganic fertilizers

A series of experiments is described in which a semi-organic fertilizer is compared to the more widely used inorganic type. A semi-organic fertilizer contains a base of organic materials to which is added a mixture of inorganic salts to make up a suitable analysis. The results from three years field trials and certain greenhouse experiments are presented. Barley was used as the test crop in all experiments.Biomass production and nitrogen accumulation were studied in the field trials.In the field trials a greater stand density was produced using the semi-organic fertilizer as compared with an inorganic fertilizer and no-fertilizer treatment. This difference was evident from early in the season and was therefore attributed to relative success in germination and/or establishment. A high salt concentration in the soil water surrounding seeds has been shown to reduce the rate and final percentage germination for a wide variety of crops. The superior stand density produced on the semi-organic treatment was probably due to the lower osmotic effect produced by that fertilizer. The results of the greenhouse experiments supported this hypothesis. Field and greenhouse experiments were not analogous with respect to the emergence observed on the no fertilizer treatment.The pattern of nitrogen uptake was different on the two fertilizer treatments. Proportionally more nitrogen was absorbed later in the season by plants growing on'the semi-organic treatment. This led to a greater nitrogen content per head on the semi-organic treatment. Although there were significantly more heads per unit area on the semi-organic treatment there was no difference in the dry weight per head, this could be due to prolonged photosynthesis in the heads on this treatment. Total biomass production was similar on the two fertilized treatments but proportionally more of the weight was in the heads on the semi-organic treatment. There was a strong negative correlation, later in the season, between plant density and a) dry weight per plant and b) nitrogen content per plant on the inorganic fertilizer treatment but this was not so on the semi-organic fertilizer

India: Domestic Issues, Strategic Dynamics, and U.S. Relations

[Excerpt] President Barack Obama’s Administration has sought to build upon the deepened U.S. engagement with India begun by President Bill Clinton in 2000 and expanded upon during much of the past decade under President G.W. Bush. This “U.S.-India 3.0” diplomacy was most recently on display in July 2011, when the second U.S.-India Strategic Dialogue session saw a large delegation of senior U.S. officials visit New Delhi to discuss a broad range of global and bilateral issues. Many analysts view the U.S.-India relationship as being among the world’s most important in coming decades and see potentially large benefits to be accrued through engagement on many convergent interests. Bilateral initiatives are underway in all areas, although independent analysts in both countries worry that the partnership has lost momentum in recent years. Outstanding areas of bilateral friction include obstacles to bilateral trade and investment, including in the high-technology sector; outsourcing; the status of conflict in Afghanistan; climate change; and stalled efforts to initiate civil nuclear cooperation. India is the world’s most populous democracy and remains firmly committed to representative government and rule of law. Its left-leaning Congress Party-led ruling national coalition has been in power for more than seven years under the leadership of Prime Minister Manmohan Singh, an Oxford-trained economist. New Delhi’s engagement with regional and other states is extensive and reflects its rising geopolitical status. The national economy has been growing rapidly—India’s is projected to be the world’s third-largest economy in the foreseeable future—yet poor infrastructure, booming energy demand, and restrictive trade and investment practices are seen to hamper full economic potential. Despite the growth of a large urban middle-class, India’s remains a largely rural and agriculture-based society, and is home to some 500-600 million people living in poverty. This report will be updated periodically

Adenosine A1 receptor activation mediates the developmental shift at layer 5 pyramidal cell synapses and is a determinant of mature synaptic strength

During the first postnatal month glutamatergic synapses between layer 5 pyramidal cells in the rodent neocortex switch from an immature state exhibiting high probability of neurotransmitter release, large unitary amplitude and synaptic depression to a mature state with decreased probability of release, smaller unitary amplitude and synaptic facilitation. Using paired recordings, we demonstrate that the developmental shift in release probability at synapses between rat somatosensory layer 5 thick-tufted pyramidal cells is due to a higher and more heterogeneous activation of presynaptic adenosine A1 receptors. Immature synapses under control conditions exhibited distributions of CV, failure rate and release probability that were almost coincident with the A1 receptor blocked condition; however, mature synapses under control conditions exhibited much broader distributions that spanned those of both the A1 receptor agonised and antagonised conditions. Immature and mature synapses expressed A1 receptors with no observable difference in functional efficacy and therefore the heterogeneous A1 receptor activation seen in the mature neocortex is due to increased adenosine concentrations that vary between synapses. Given the central role demonstrated for A1 receptor activation in determining synaptic amplitude and the statistics of transmission between mature layer 5 pyramidal cells, the emplacement of adenosine sources and sinks near the synaptic terminal could constitute a novel form of long-term synaptic plasticity

Severe intellectual disability: systematic review of the prevalence and nature of presentation of unipolar depression

Background The diagnosis of depression in severe and profound intellectual disability is challenging. Without adequate skills in verbal self-expression, standardized diagnostic criteria cannot be used with confidence. The purpose of this systematic review was to investigate the assessment and diagnosis of unipolar depression in severe and profound intellectual disability. The review aimed to examine the methods used to assess for depression. The secondary aim was to explore the frequency and symptoms of depression. Methods The PRISMA (2009) Checklist for systematic review was followed, and a search of electronic databases was undertaken. Nine studies were included in the qualitative synthesis from over 2000 records identified. Results The quality of the studies was assessed and scored, with a wide range of results. Individual studies scored between 2 and 7 of a maximum possible score of 8. The diagnostic tools utilized by each of the studies were assessed and compared. Conclusions In terms of the methods used to assess for depression, results were varied. This was due to the heterogeneous nature of the individual study designs. The Aberrant Behaviour Checklist consistently showed promise, in particular when combined with other instruments or clinical examination. Qualitative analysis of the selected studies has shown a wide variation in the quality of primary research in this field, with more required to make firm conclusions regarding the diagnosis, frequency and presentation of depression in severe and profound intellectual disability

Visfatin reduces gap junction mediated cell-to-cell communication in proximal tubule-derived epithelial cells

Background/Aims: In the current study we examined if the adipocytokine, visfatin, alters connexin-mediated intercellular communication in proximal tubule-derived epithelial cells. Methods: The effects of visfatin (10-200ng/mL) on cell viability and cytotoxicity in HK2-cells were assessed by MTT, crystal violet and lactate dehydrogenase assays. Western blot analysis was used to confirm expression of Cx26, Cx40 and Cx43. The effect of visfatin (10-200ng/mL) on TGF-β1 secretion was confirmed by ELISA, and the effects of both TGF-β1 (2-10ng/mL) and visfatin (10-200ng/mL) on connexin expression were assessed by western blot. Functional intercellular communication was determined using transfer of Lucifer Yellow and paired-whole cell patch clamp electrophysiology. Results: In low glucose (5mM), visfatin (10-200ng/mL) did not affect membrane integrity, cytotoxicity or cell viability at 48hrs, but did evoke a concentration-dependent reduction in Cx26 and Cx43 expression. The expression of Cx40 was unaffected. At 48hrs, visfatin (10-200ng/mL) increased the secretion of TGF-β1 and the visfatin-evoked changes in connexin expression were mimicked by exogenous application of the pro-fibrotic cytokine (2-10ng/ml). Visfatin reduced dye transfer between coupled cells and decreased functional conductance, with levels falling by 63% as compared to control. Although input resistance was increased following visfatin treatment by 166%, the change was not significant as compared to control. The effects of visfatin on Cx-expression and cell-coupling were blocked in the presence of a TGF-β1 specific neutralizing antibody. Conclusions: The adipocytokine visfatin selectively evoked a non-toxic reduction in connexin expression in HK2-cells. The loss in gap-junction associated proteins was mirrored by a loss in functional conductance between coupled cells. Visfatin increased TGF-β secretion and the pattern of change for connexins expression was mimicked by exogenous application of TGF-β1. The effect of visfatin on Cx-expression and dye transfer were negated in the presence of a TGF-β1 neutralising antibody. These data suggest that visfatin reduces connexin-mediated intercellular communication in proximal tubule-derived epithelial cells via a TGF-β dependent pathway. © 2013 S. Karger AG, Base

The role of adenosine in the modulation of synaptic transmission and action potential firing of thick-tufted layer 5 pyramidal neurons

The actions of many neuromodulators induce changes in synaptic transmission and membrane excitability, and many of these effects are well documented in neurons across the CNS. Adenosine acts as a powerful modulator across the CNS and while its actions have been characterised in some neurons in the neocortex, its effects on excitatory transmission in layer 5 remain unstudied. Adenosine has been implicated in the modulation of spontaneous activity generated in the layer 5 excitatory network, thus understanding its actions in this area are of substantial importance. This study used a combined approach of paired intracellular recordings and quantitative modelling to investigate the actions of adenosine on thick-tufted layer 5 pyramidal neurons in the rat somatosensory cortex. Adenosine was found to powerfully suppress synaptic transmission between these neurons and the changes in synaptic dynamics could be precisely captured as a change only in probability of release in a simple phenomenological model. Recordings conducted at three post-natal ages provide evidence that an increased tone of endogenous adenosine is responsible for the previously described developmental shift in short-term dynamics and reliability of this synapse. The data illustrates both that this endogenous activation of A1 receptors is highly heterogeneous, with variation between neighbouring synapses, and that it plays a significant role in EPSP parameters observed at mature connections. An investigation into adenosine's post-synaptic actions using an approach that measures the neurons' I-V response to naturalistic current inputs demonstrates how adenosine's actions on membrane excitability translate to a strong suppression of spiking. Simultaneous dendritic and somatic recordings demonstrate that this effect is enhanced when current is injected from the dendrite and that back-propagating bursts of action potentials are selectively suppressed by adenosine. As a whole the work illustrates that the effects of adenosine can be well captured by mathematically tractable quantitative models