Fusion of indigenous knowledge and gamma spectrometry for soil mapping to support knowledge-based extension in Tanzania

Food shortages often threaten central Tanzania. Sustainable action adapted to local environmental conditions is desperately needed. In the framework of the TransSEC project, two food value chains in the Dodoma region of Tanzania were inspected in order to make propositions for improvement , spanning from soil preparation to product consumption. Therefore, soil mapping approaches were required to obtain rapid and reliable information. This would enable local farmers to participate in the development of upgrading strategies and extensionists to develop recommendations that take local soil conditions into account. In this study, a combination of participatory soil mapping and gamma ray spectrometry-assisted transect mapping was applied to establish local soil maps of two villages in the Dodoma region. Participatory mapping included key informant interviews, group discussions and transect walks. Local farmers indicated reference profiles for local soil types. Their gamma radiation signatures delivered base information for further soil exploration and soil unit delineation in the field. Finally, high resolution satellite images were used to establish the village soil maps. This approach allows capture of the major soil differences within a village territory and reduction of the costs of chemical analyses. Challenges were soil unit separation with gamma ray spectrometry due to erosional redistribution processes at the surface, correct translation of specific terms from local tongues as well as variable individual soil knowledge of local participants. Ultimately, the combination of local soil knowledge with innovative scientific mapping yielded quick results with sufficient spatial resolution for extension work.     

Elastic Space: Latent Formations in Fashion and Architecture

In search of an architectural response to shifting contemporary environments, the paper investigates the notion of latency in the related fields of sartorial fashion and architecture. The paper unfolds the possibility of a material and phenomenal elasticity that facilitates responsive architecture through a re-coding and re-contextualization of user, occupation and space.     

Radikalabfang. III [1] ESR-spektroskopische Untersuchung von Radikalreaktionen eines bicyclischen 1-Hydroxy-3-imidazolin-3-oxids [2]

Spin Trapping. III. Studies of Radical Reactions of a Bicyclic 1-Hydroxy-3-imidazoline-3-oxide Radical addition reactions to the nitrono group and the oxidation of the 8-hydroxy-1,4,5,7-tetramethyl-6,8-diazabicyclo[3.2.1]oct-6-en-6-oxide 2b were investigated by e.s.r.-spectroscopy. Oxidation of 2b by Ag₂O, PbO₂, hydrogenperoxide, tert.-butoxy and benzoyloxy radicals, respectively, yields a bicyclic nitroxide with typical a(N)-value (1,9 mT). Testing a wide range of carbon-centered radicals we did not find, however, any spin adducts in contrast to the literature. Only H-atoms are found to add to the nitrone function of 2b giving a bicyclic nitroxide 4b (R′ = H) with a(N)-value of 1,4 mT, a(H_ax) = 2,4 mT. The relationship between a ring-chain tautomerism of 2 as previously described and the formation of radicals has been demonstrated by radical reactions of derivatives of ring opened isomers 5b .     

Reaktionen des 2,6-Di-tert.-butyl-4-(N-tert.-butylnitrono)-phenoxyradikals

Reactions of the 2,6-Di-tert.-butyl-4-(N-tert.-butylnitrono)-phenoxyl Radical The title compound, a phenoxyl radical containing a nitrono group, reacts with alcohols and tert.-butylhydroperoxide yielding phenol and products of secondary radical solvent reactions. The reactions with lead tetraacetate, tert.-butoxy and 2-cyanoisopropyl radicals give high yields of cyclohexadienone adducts ( 6, 7 and 10 ) containing unchanged nitrono function. The reaction with dibenzoylperoxide, however, leads to the modification of the nitrono group yielding the N-benzoyloxycarboxamide ( 8 ). In the acidic decomposition of the tert.-butoxy radical adduct we suggest a nitrenium ion ( 16 ) as an intermediate.     

Gaschromatographische Untersuchung stereoisomerer Cyclotrideca-1,5,9-triene

Gas Chromatographic Investigation of Stereoisomeric Cyclotrideca-1,5,9-trienes Using achiral phases of different polarity in capillary gas chromatography on the one hand and a chiral cyclodextrine phase on the other hand it is demonstrated, that a ring-enlargement sequence starting from (E, E, Z)-cyclododeca-1,5,9-triene yields five of the six theoretically possible isomeric cyclotrideca-1,5,9-trienes and (E, Z)-trans-bicyclo[10.1.0]trideca- 4,8-diene. With all achiral phases only three of the isomeric trienes and the bicyclic isomer were separated from each other; (E, Z, E)- and (Z, E, Z)-cyclotrideca-1,5,9-triene are eluated in only one (the fifth) peak, these isomers were separated on the cyclodextrine phase. Moreover, this chiral phase separates the enantiomers of the bicyclic isomer.     

Short communication: The preruminant calf as a model for characterizing the effects of vitamin D status in the neonate

The objective of this study was to evaluate the feasibility of using the preruminant dairy calf as a model for evaluating effects of vitamin D status in the neonate. Because the newborn calf can be sustained during the first weeks of life solely on a fluid diet having a defined composition, has documented nutritional requirements, and is minimally affected by repeated samplings of peripheral blood, it has the potential to serve as a model for characterizing nutrient-specific effects on the growth and health of the neonate. Colostrum-fed Holstein bull calves (n = 13) entered the trial at approximately 4 d of age. All calves were fed a custom-formulated milk replacer devoid of vitamin D. Plasma 25-hydroxyvitamin D₃ concentrations in all calves were determined on a regular basis beginning at d 0. Using this information, low- and high-status groups of calves were established by subcutaneous administration of 25-hydroxyvitamin D₃. To maintain targeted plasma 25-hydroxyvitamin D₃ concentrations in low (<30 ng/mL) and high (>60 ng/mL) vitamin D-status calves, low-status calves (n = 6) received a total of 8,600 IU (2,225 IU/wk) of vitamin D during the experimental period and high-status calves (n = 7) received 54,000 IU (13,500 IU/wk). Concentrations of 25-hydroxyvitamin D₃ in low-status calves averaged 27 ng/mL, compared with 78 ng/mL in high-status calves, and were less at all sampling times from d 7 to d 28. Concentrations of 1,25-dihydroxyvitamin D₃ and 25-hydroxyvitamin D₃ were not correlated. Calcium, magnesium, and phosphorous concentrations were unaffected by 25-hydroxyvitamin D₃ administration; however, plasma calcium and 1,25-dihydroxyvitamin D₃ concentrations were correlated. Calcium and magnesium concentrations decreased with age but remained within normal ranges for dairy cattle. These results indicate that it is possible to predictably control vitamin D status over a 28-d period and suggest that the preruminant calf might be useful as a model for studying effects of vitamin D on growth, development, and immune function in the neonate.     

The profound impact of negative power law noise on statistical estimation

This paper investigates the profound impact of negative power law (neg-p) noise-that is, noise with a power spectral density L_p(f) ? | f |^p for p < 0 - on the ability of practical implementations of statistical estimation or fitting techniques, such as a least squares fit (LSQF) or a Kalman filter, to generate valid results. It demonstrates that such neg-p noise behaves more like systematic error than conventional noise, because neg-p noise is highly correlated, non-stationary, non-mean ergodic, and has an infinite correlation time ?_c. It is further demonstrated that stationary but correlated noise will also cause invalid estimation behavior when the condition T ? ?_c is not met, where T is the data collection interval for estimation. Thus, it is shown that neg-p noise, with its infinite ?_c, can generate anomalous estimation results for all values of T, except in certain circumstances. A covariant theory is developed explaining much of this anomalous estimation behavior. However, simulations of the estimation behavior of neg-p noise demonstrate that the subject cannot be fully understood in terms of covariant theory or mean ergodicity. It is finally conjectured that one must investigate the variance ergodicity properties of neg-p noise through the use of 4th order correlation theory to fully explain such simulated behavior.     

Two- and three-dimensional transient melt-flow simulation in vapour-pressure-controlled Czochralski crystal growth

Flow and thermal properties associated with semiconductor melt flow in an axisymmetric crucible container are studied numerically. Axisymmetric and three-dimensional computational solutions are obtained using a standard-Galerkin, finite-element solver. The crucible and crystal are optionally rotated, and the influence of gravity (through buoyancy) is accounted for via a Boussinesq approximation in the controlling Navier–Stokes equations. The results indicate a strong dependence of the flow on both rotation and buoyancy. Results for axisymmetric flows, computed with both flat and curved geometries, are presented first, and strongly suggest that rotation of crystal and crucible in the same direction (iso-rotation) is most favourable for producing a desired convexity for the crystal/melt interface. Three-dimensional results are then presented for higher Reynolds numbers, and, in particular, reveal that for iso-rotation under moderate buoyancy, the flow undergoes a switch from a steady 2D state to an unsteady 3D state, and that the temperature becomes non-trivially advected by the flow beneath the crystal. Further evidence reveals however, that on a time scale more appropriate to the crystal growth process, the (time-averaged) flow has a weaker three-dimensionality, in relation to the mean axisymmetric part, and there is only slight distortion to the temperature field beneath the crystal. A detailed examination of the instability properties is also made, revealing the underlying nonlinear mode interaction and associated frequency responses around the bifurcation point.