Sensitivity of an image plate system in the XUV (60 eV < E < 900 eV)

Phosphor imaging plates (IPs) have been calibrated and proven useful for quantitative x-ray imaging in the 1 to over 1000 keV energy range. In this paper we report on calibration measurements made at XUV energies in the 60 to 900 eV energy range using beamline 6.3.2 at the Advanced Light Source at Lawrence Berkeley National Laboratory. We measured a sensitivity of ~25 plus or minus 15 counts/pJ over the stated energy range which is compatible with the sensitivity of Si photodiodes that are used for time-resolved measurements. Our measurements at 900 eV are consistent with the measurements made by Meadowcroft et al. at ~1 keV.Comment: 7 pages, 2 figure

Village Baseline Study: Site Analysis Report for Usambara – Lushoto, Tanzania (TZ0105)

The village baseline study of Kwang’wenda village in the CCAFS benchmark Lushoto site, Tanzania took place from April 27 to 29, 2011. Focus group discussions were conducted separately for men and women. Population growth and agriculture intensification have led to encroachment onto the forest areas, reduction in riparian vegetation, cultivation along the riverbank, and soil fertility depletion on the farmland. The overall area under farming has increased but individual farms have become smaller and production per unit area has reduced due to land subdivision. The community’s vision of the future includes the conservation and expansion of the forest area by planting more trees and enforcing restrictions on illegal logging. It also calls for promoting agroforestry systems in the farmlands and allowing riverine vegetation to mature, in order to ensure clean waters in the rivers. The discussion groups identified 32 organisations, and 60% of them were involved in food security assistance, prioritizing food availability. Radio is the most significant source of information on agriculture in the village. Men were better informed about and interacted with groups that operated beyond the locality, while women were more aware of and engaged in groups that operated within the community but had limited operational capacity

Search for the Hypothetical pi -> mu x Decay

The KARMEN collaboration has reported the possible observation of a hitherto unknown neutral and weakly interacting particle x, which is produced in the decay pi -> mu + x with a mass m(x) = 33.9 MeV. We have searched for this hypothetical decay branch by studying muons from pion decay in flight with the LEPS spectrometer at the piE3 channel at PSI and find branching ratios BR(pi- to mu- anti-x) < 4e-7 and BR(pi+ to mu+ x) < 7e-8 (95\% C.L.). Together with the limit BR > 2e-8 derived in a recent theoretical paper our result would leave only a narrow region for the existence of x if it is a heavy neutrino.Comment: 10 pages, TeX (uses epsf), 3 Postscript figures uu-encode

Village Baseline Study: Site Analysis Report for Makueni – Wote, Kenya (KE0202)

The village baseline study of Kithoni village in the CCAFS benchmark site of Makueni, Kenya took place from June 11th – 14th, 2012. Focus group discussions were conducted separately for men and women. The village is in a marginal landscape and is food insecure. Frequent droughts and crop failures plague the area. The biggest constraint to agricultural production is the shortage of water. Land holdings have become increasingly smaller due to the increase in human population. The government has to frequently provide relief food during times of crisis. There are many organisations operating in the village, but there is a lack of concerted efforts between them, particularly those working in food security and natural resource management. Very few organisations are working on the food crisis situation in the area, although this is a frequently recurring issue. Networks of information for agricultural advice are based mainly on the radio and friends/neighbours. All the organisations mentioned as providing information are those that operate beyond the locality. There is potential to link these organisations with community groups and individuals especially to develop a feedback mechanism so that the flow of information is two-way. The FM stations can also be supplied with a wider range of information to disseminate. However, this must be in line with the community needs which should be established beforehand

Village Baseline Study: Site Analysis Report for Xai Xai, Zongoene Village, Bairro 1, Mozambique

This is the report of the village baseline study of Zongoene Village, Bairro 1, in the CCAFS benchmark site of Xai Xai, Mozambique in May 2013 to complement an earlier household baseline survey done in the same village. Zongoene village is located by the coast at the mouth of the Limpopo River where there are extensive wetlands along with forests and sand dunes. The village is divided into five sections: Bairro 1, Bairro 2, Bairro 3, Bairro 4 and Bairro 5. Zongoene is the result of a government resettlement program that brought people together to ease service provision. Nonetheless, the level and quality of services remain very low with roads in bad condition, local schools poorly built and lacking water, one hospital with insufficient staff and resources, and nascent electrical availability. The concentrated and expanding population is also increasing pressures on the environment as demand for food and farmland grows

Low Energy Analyzing Powers in Pion-Proton Elastic Scattering

Analyzing powers of pion-proton elastic scattering have been measured at PSI with the Low Energy Pion Spectrometer LEPS as well as a novel polarized scintillator target. Angular distributions between 40 and 120 deg (c.m.) were taken at 45.2, 51.2, 57.2, 68.5, 77.2, and 87.2 MeV incoming pion kinetic energy for pi+ p scattering, and at 67.3 and 87.2 MeV for pi- p scattering. These new measurements constitute a substantial extension of the polarization data base at low energies. Predictions from phase shift analyses are compared with the experimental results, and deviations are observed at low energies.Comment: 15 pages, 4 figure

Village Baseline Study: Site Analysis Report for Chicualacuala, Maluana, Mozambique (MO0145)

This is the report of the village baseline study of Maluana village in the CCAFS benchmark site of Chicualacuala, Mozambique from May 5-12, 2013 to complement an earlier household baseline survey done in the same village

Time-resolved nuclear spin-dependent small-angle neutron scattering from polarised proton domains in deuterated solutions

Abstract.: We have investigated the process of dynamic proton polarisation by means of time-resolved polarised small-angle neutron scattering (SANS) on frozen solutions of EHBA-CrV molecules in glycerol-water mixtures as a function of the concentration of EHBA-CrV and for different degrees of deuteration of the solvent. In the EHBA-CrV complex, the spins of the 20 protons which surround the paramagnetic CrV can be oriented using the method of dynamic nuclear polarisation (DNP), thereby offering the possibility to create locally a nuclear spin-dependent contrast for SANS. The time constants which describe the build-up of polarisation around the paramagnetic centre and the subsequent diffusion of polarisation in the solvent were determined by analysing the temporal evolution of the nuclear polarisation, which in turn was obtained by fitting a core-shell model to the time-dependent SANS curves. The results on the spin dynamics obtained using the scattering function of a core-shell could be independently confirmed by evaluating the integrated SANS intensity. A thermodynamic one-centre model is presented which is able to reproduce the observed dependence of the proton polarisation times on the proton concentration of the solven

Trace-gas metabolic versatility of the facultative methanotroph Methylocella silvestris

The climate-active gas methane is generated both by biological processes and by thermogenic decomposition of fossil organic material, which forms methane and short-chain alkanes, principally ethane, propane and butane1, 2. In addition to natural sources, environments are exposed to anthropogenic inputs of all these gases from oil and gas extraction and distribution. The gases provide carbon and/or energy for a diverse range of microorganisms that can metabolize them in both anoxic3 and oxic zones. Aerobic methanotrophs, which can assimilate methane, have been considered to be entirely distinct from utilizers of short-chain alkanes, and studies of environments exposed to mixtures of methane and multi-carbon alkanes have assumed that disparate groups of microorganisms are responsible for the metabolism of these gases. Here we describe the mechanism by which a single bacterial strain, Methylocella silvestris, can use methane or propane as a carbon and energy source, documenting a methanotroph that can utilize a short-chain alkane as an alternative to methane. Furthermore, during growth on a mixture of these gases, efficient consumption of both gases occurred at the same time. Two soluble di-iron centre monooxygenase (SDIMO) gene clusters were identified and were found to be differentially expressed during bacterial growth on these gases, although both were required for efficient propane utilization. This report of a methanotroph expressing an additional SDIMO that seems to be uniquely involved in short-chain alkane metabolism suggests that such metabolic flexibility may be important in many environments where methane and short-chain alkanes co-occur

Classification of Light-Induced Desorption of Alkali Atoms in Glass Cells Used in Atomic Physics Experiments

We attempt to provide physical interpretations of light-induced desorption phenomena that have recently been observed for alkali atoms on glass surfaces of alkali vapor cells used in atomic physics experiments. We find that the observed desorption phenomena are closely related to recent studies in surface science, and can probably be understood in the context of these results. If classified in terms of the photon-energy dependence, the coverage and the bonding state of the alkali adsorbates, the phenomena fall into two categories: It appears very likely that the neutralization of isolated ionic adsorbates by photo-excited electron transfer from the substrate is the origin of the desorption induced by ultraviolet light in ultrahigh vacuum cells. The desorption observed in low temperature cells, on the other hand, which is resonantly dependent on photon energy in the visible light range, is quite similar to light-induced desorption stimulated by localized electronic excitation on metallic aggregates. More detailed studies of light-induced desorption events from surfaces well characterized with respect to alkali coverage-dependent ionicity and aggregate morphology appear highly desirable for the development of more efficient alkali atom sources suitable to improve a variety of atomic physics experiments.Comment: 6 pages, 1 figure; minor corrections made, published in e-Journal of Surface Science and Nanotechnology at http://www.jstage.jst.go.jp/article/ejssnt/4/0/4_63/_articl