I'm a celebrity, get me into politics: the political celebrity and the celebrity politician

This chapter discusses the political celebrity and the celebrity politician

X-Ray Wakes in Abell 160

`Wakes' of X-ray emission have now been detected trailing behind a few (at least seven) elliptical galaxies in clusters. To quantify how widespread this phenomenon is, and what its nature might be, we have obtained a deep (70 ksec) X-ray image of the poor cluster Abell 160 using the ROSAT HRI. Combining the X-ray data with optical positions of confirmed cluster members, and applying a statistic designed to search for wake-like excesses, we confirm that this phenomenon is observed in galaxies in this cluster. The probability that the detections arise from chance is less than 0.0038. Further, the wakes are not randomly distributed in direction, but are preferentially oriented pointing away from the cluster centre. This arrangement can be explained by a simple model in which wakes arise from the stripping of their host galaxies' interstellar media due to ram pressure against the intracluster medium through which they travel.Comment: 7 pages, 7 figures, accepted for publication in MNRA

Promoting Sustainable Pro-Poor Growth in Rwandan Agriculture: What are the Policy Options?

In 2000, as part of its strategy for growth and poverty reduction, the Government of Rwanda set a goal to increase per capita income from US$230 to US$900 and halve the incidence of poverty by 2020. Two years after those targets were established Rwanda's first Poverty Reduction Strategy Paper (PRSP) projected that GDP growth in the range of 6 to 7 percent would be needed over the long term for those targets to be realized. The principal sources of growth in the short to medium term were to be the agriculture and manufacturing sectors, with agricultural projected to start at 5.2 percent and accelerate over the period due to productivity improvements. Manufacturing growth was projected to rise sharply to 11.5 percent, based on the expansion of manufacturing capacity in agro-processing, and then slow to a more sustainable level of 7 percent. Between 1995 and 2005, real GDP grew at an average annual rate of 10 percent as the economy recovered from the effects of the 1994 genocide. Real GDP growth is now slowing, however. Between 2001 and 2005, average annual GDP growth averaged only 5.2 percent. If growth continues below 6 percent, this will be insufficient to reach Government's development targets. Government therefore needs to quickly put in place policies to accelerate growth. Transforming the agriculture sector will be a critical element of any growth strategy. Agriculture accounts for 35-40 percent of GDP, and employs around 80 percent of the population. It is also the main source of foreign exchange, and is the primary source of inputs for the manufacturing sector. Yet agricultural growth has been disappointing. Between 2001 and 2005, agricultural growth averaged 4.2 percent per year, below the target range of 5 to 8 percent set out in the PRSP. In recognition of the need to stimulate further sustained growth in agriculture, the government is now poised to identify and prioritize the key interventions. This paper aims to assist government in prioritizing the key measures by examining how the level of agricultural growth needed to achieve the government's policy objectives can be achieved. Some in Rwanda advocate the promotion of export crops, both traditional export crops (e.g., coffee, tea, pyrethrum, hides and skins) and non-traditional export crops (e.g., cut flowers, fruits, vegetables, essential oils, vanilla, silk, macadamia). Others argue that agricultural growth can best be stimulated in the short- to medium-term by increasing productivity in food staples, both crops and livestock. This debate mirrors those ongoing in many other developing countries, in sub-Saharan Africa and elsewhere. An economy-wide, multi-market model (REMM) was developed to test the likely payoffs to alternative agricultural development strategies. The REMM is disaggregated to the sub-national (provincial) level and includes 30 agricultural sectors (commodities) and two aggregate non-agricultural sectors. Eight household types are identified within each province according to size of landholding and gender of household head. The economy-wide model is linked to a micro-simulation model that includes all households sampled in a nationally representative survey (19992001 Household Living Condition Survey). The macro-micro linkage framework permits assessment of the likely impacts of alternative policy scenarios on growth, incomes and poverty, and food security at national, sub-national, and household group levels. The model was first used to simulate a base run scenario representing the "business as usual" option, under which agricultural and non-agricultural growth are assumed to continue along current trends. Alternative growth scenarios were later evaluated relative to this baseline. The modelling results show that business as usual is not an option if Rwanda is to meet its national development targets, including the Millennium Development Goals (MDGs) and the targets agreed to under the New Economic Partnership for Africa's Development (NEPAD). The base run scenario highlights that a continuation of current policies will bring about a modest reduction in the national poverty rate, but the absolute number of people living below the poverty line will increase because of population growth. Food self-sufficiency at the national level will be eroded in the face of demographic pressure and rising food imports. The simulations conducted using the REMM indicate that rapid and sustainable growth in Rwanda's agricultural sector is achievable only if the productivity, profitability, and competitiveness of agriculture is improved. Therefore, the priority measures identified focus on increasing investments in land and water resources, strengthening extension, promoting the performance of both domestic and export markets. Key to this will be strengthening support to producer organizations. The simulations produced a number of insights to inform policy design: - Agriculture has the potential to be a leading engine of growth for Rwanda's economy over the short to medium term - Within agriculture, the main drivers of growth will be food staples, including livestock. - Staple-led growth is more pro-poor than export-led growth. - Growth in staples will reduce the nation's food deficit, but it will not eliminate imports of all commodities. - Growth in agricultural exports will help to reduce the total trade deficit, but it will not be able to eliminate it completely. - Agricultural growth will contribute to the attainment of the first MDG of halving poverty by 2015, but agricultural growth alone will not to be sufficient. These findings from Rwanda are relevant for the many other developing countries, in sub-Saharan Africa and also in other regions, in which policy makers are struggling to unlock the power of agriculture to serve as a driver of growth and poverty reduction. In recent years, much attention has focused on boosting agricultural growth by promoting the development of high-value export crops. The REMM simulation results serve as a reminder that in agrarian economies in which a large proportion of rural households continue to engage in production of food staples destined for home consumption, investments aimed at raising the productivity of food staples are likely to have a much greater impact in the short to medium term in fostering broad-based, pro-poor growth.Environmental Economics and Policy, International Development,

Conformational Preferences of 3-(Dimethylazinoyl)propanoic Acid as a Function of pH and Solvent; Intermolecular versus Intramolecular Hydrogen Bonding

The conformational equilibrium of 3-(dimethylazinoyl)propanoic acid (DMAPA, azinoyl = N^+(O^−) has a weak pH-dependence in D_2O, with a slight preference for trans in alkaline solutions. The acid ionization constants of the protonated amine oxide and carboxylic functional groups as determined by NMR spectroscopy were 7.9 × 10^(−4) and 6.3 × 10^(−6), respectively. The corresponding value of K_1/K_2 of 1.3 × 10^2 is not deemed large enough to provide experimental NMR evidence for a significant degree of intramolecular hydrogen bonding in D_2O. Conformational preferences of DMAPA are mostly close to statistical (gauche/trans = 2/1) in other protic solvents, e.g., alcohols. However, the un-ionized form of DMAPA appears to be strongly intramolecularly hydrogen-bonded and gauche in aprotic solvents

Globally Distributed Energetic Neutral Atom Maps for the "Croissant" Heliosphere

A recent study by Opher et al. (2015) suggested the heliosphere has a "croissant" shape, where the heliosheath plasma is confined by the toroidal solar magnetic field. The "croissant" heliosphere is in contrast to the classically accepted view of a comet-like tail. We investigate the effect of the "croissant" heliosphere model on energetic neutral atom (ENA) maps. Regardless of the existence of a split tail, the confinement of the heliosheath plasma should appear in ENA maps. ENA maps from the Interstellar Boundary Explorer (IBEX) have shown two high latitude lobes with excess ENA flux at higher energies in the tail of the heliosphere. These lobes could be a signature of the confinement of the heliosheath plasma, while some have argued they are caused by the fast/slow solar wind profile. Here we present ENA maps of the "croissant" heliosphere, focusing on understanding the effect of the heliosheath plasma collimation by the solar magnetic field while using a uniform solar wind. We incorporate pick-up ions (PUIs) into our model based on Malama et al. (2006) and Zank et al. (2010). We use the neutral solution from our MHD model to determine the angular variation of the PUIs, and include the extinction of PUIs in the heliosheath. In the presence of a uniform solar wind, we find that the collimation in the "croissant" heliosphere does manifest itself into two high latitude lobes of increased ENA flux in the downwind direction.Comment: 14 pages, 1 table, 7 figures, Accepted for publication in Ap

Non-detection of L-band Line Emission from the Exoplanet HD189733b

We attempt to confirm bright non-local thermodynamic equilibrium (non-LTE) emission from the exoplanet HD 189733b at 3.25 μm, as recently reported by Swain et al. based on observations at low spectral resolving power (λ/δλ ≈ 30). Non-LTE emission lines from gas in an exoplanet atmosphere will not be significantly broadened by collisions, so the measured emission intensity per resolution element must be substantially brighter when observed at high spectral resolving power. We observed the planet before, during, and after a secondary eclipse event at a resolving power λ/δλ = 27, 000 using the NIRSPEC spectrometer on the Keck II telescope. Our spectra cover a spectral window near the peak found by Swain et al., and we compare emission cases that could account for the magnitude and wavelength dependence of the Swain et al. result with our final spectral residuals. To model the expected line emission, we use a general non-equilibrium formulation to synthesize emission features from all plausible molecules that emit in this spectral region. In every case, we detect no line emission to a high degree of confidence. After considering possible explanations for the Swain et al. results and the disparity with our own data, we conclude that an astrophysical source for the putative non-LTE emission is unlikely. We note that the wavelength dependence of the signal seen by Swain et al. closely matches the 2ν_2 band of water vapor at 300 K, and we suggest that an imperfect correction for telluric water is the source of the feature claimed by Swain et al

A Search for a Sub-Earth Sized Companion to GJ 436 and a Novel Method to Calibrate Warm Spitzer IRAC Observations

We discovered evidence for a possible additional 0.75 R_Earth transiting planet in the NASA EPOXI observations of the known M dwarf exoplanetary system GJ 436. Based on an ephemeris determined from the EPOXI data, we predicted a transit event in an extant Spitzer Space Telescope 8 micron data set of this star. Our subsequent analysis of those Spitzer data confirmed the signal of the predicted depth and at the predicted time, but we found that the transit depth was dependent on the aperture used to perform the photometry. Based on these suggestive findings, we gathered new Warm Spitzer Observations of GJ 436 at 4.5 microns spanning a time of transit predicted from the EPOXI and Spitzer 8 micron candidate events. The 4.5 micron data permit us to rule out a transit at high confidence, and we conclude that the earlier candidate transit signals resulted from correlated noise in the EPOXI and Spitzer 8 micron observations. In the course of this investigation, we developed a novel method for correcting the intrapixel sensitivity variations of the 3.6 and 4.5 micron channels of the Infrared Array Camera (IRAC) instrument. We demonstrate the sensitivity of Warm Spitzer observations of M dwarfs to confirm sub-Earth sized planets. Our analysis will inform similar work that will be undertaken to use Warm Spitzer observations to confirm rocky planets discovered by the Kepler mission.Comment: 22 pages, 8 figures, accepted for publication in PAS

Workshop on Mars Sample Return Science

Martian magnetic history; quarantine issues; surface modifying processes; climate and atmosphere; sampling sites and strategies; and life sciences were among the topics discussed

Automation of a Positron-emission Tomography (PET) Radiotracer Synthesis Protocol for Clinical Production.

The development of new positron-emission tomography (PET) tracers is enabling researchers and clinicians to image an increasingly wide array of biological targets and processes. However, the increasing number of different tracers creates challenges for their production at radiopharmacies. While historically it has been practical to dedicate a custom-configured radiosynthesizer and hot cell for the repeated production of each individual tracer, it is becoming necessary to change this workflow. Recent commercial radiosynthesizers based on disposable cassettes/kits for each tracer simplify the production of multiple tracers with one set of equipment by eliminating the need for custom tracer-specific modifications. Furthermore, some of these radiosynthesizers enable the operator to develop and optimize their own synthesis protocols in addition to purchasing commercially-available kits. In this protocol, we describe the general procedure for how the manual synthesis of a new PET tracer can be automated on one of these radiosynthesizers and validated for the production of clinical-grade tracers. As an example, we use the ELIXYS radiosynthesizer, a flexible cassette-based radiochemistry tool that can support both PET tracer development efforts, as well as routine clinical probe manufacturing on the same system, to produce [18F]Clofarabine ([18F]CFA), a PET tracer to measure in vivo deoxycytidine kinase (dCK) enzyme activity. Translating a manual synthesis involves breaking down the synthetic protocol into basic radiochemistry processes that are then translated into intuitive chemistry "unit operations" supported by the synthesizer software. These operations can then rapidly be converted into an automated synthesis program by assembling them using the drag-and-drop interface. After basic testing, the synthesis and purification procedure may require optimization to achieve the desired yield and purity. Once the desired performance is achieved, a validation of the synthesis is carried out to determine its suitability for the production of the radiotracer for clinical use