Cadmium Content of South African Table Wines

Red and white South African table wines from the major wine producing districts were analysed for cadmium content. Only three wines had a slightly higher concentration than 0,010 mg/ t The average cadmium concentration was 0,003 mg/ f, and no relationship between cadmium content and origin could be determined

Observation of light dragging in rubidium vapor cell

We report on the experimental demonstration of light dragging effect due to atomic motion in a rubidium vapor cell. We found that the minimum group velocity is achieved for light red-shifted from the center of the atomic resonance, and that the value of this shift increases with decreasing group velocity, in agreement with the theoretical predictions by Kocharovskaya, Rostovtsev, and Scully [Phys. Rev. Lett. {\bf 86}, 628 (2001)].Comment: 4 pages 4 figures, submitted to PR

Surgical reconstruction of Northern Uganda war victims.

Background: Aid groups estimate that since 1086 when the war conflicts in Northern Uganda started, over 30,000 people have died in the insurgency and over 20,000 people have remained maimed. Arising from the conflict, innocent civilians have had their limbs, lips, eyes, ears, noses, breasts, fingers and toes cut off.Patients and Methods: Between 2004 and 2005, a total of 34 victims of the Northern Uganda war, underwent reconstructive surgery. Most of the patients were treated from the local hospitals of Lira, Gulu and Kitgum.Results: Between 2004 and 2006, the Plastic Surgery team of Mulago hospital rehabilitated 34 victims of the northern war. Of these 23 were females and 11 were males. Most of these people had suffered severe disfigurements which necessitated multiple staged reconstructive procedures on them. The majority of the reconstructive operations were on the lips despite the fact that many victims had also suffered from mutilation of other body parts.Conclusion: Effects of the insurgency on individuals, families and communities included: Increased burden on health care delivery Hospital capacity overwhelmed with few doctors and nurses available Increased number of traumatised people Increased number of war causalities Population maimed with body parts cut off Increased dependency of local population on hand outs from government and relief agencies.Hence the need to strive for peaceful resolution of the Northern Uganda war conflict

Congenital pseudarthrosis of the tibia - treatment with free valcusarised fibular grafts

Congenital pseudarthrosis is uncommon. We report on a series of 4 patients treated by means of free vascularised fibular grafts. Complications encountered were graft fracture, delayed union and angulation deformities. Modifications in the surgical technique i=proved later results. We recommend wide excision of pathological bone, bridging of the defect by free vascularised fibular grafts and rigid fixation

Congenital pseudarthrosis of the tibia : treatment with free vascularised fibular grafts

CITATION: Smith, C. S. F., Zeeman, V. R. B. J. & Wade, W. J. 1993. Congenital pseudarthrosis of the tibia : treatment with free vascularised fibular grafts. South African Medical Journal, 83:750-752.The original publication is available at http://www.samj.org.zaCongenital pseudarthrosis is uncommon. We report on a series of 4 patients treated by means of free vascularised fibular grafts. Complications encountered were graft fracture, delayed union and angulation deformities. Modifications in the surgical technique improved later results. We recommend wide excision of pathological bone, bridging of the defect by free vascularised fibular grafts and rigid fixation.Publisher’s versio

Nitrous oxide net exchange in a beech dominated mixed forest in Switzerland measured with a quantum cascade laser spectrometer

International audienceNitrous oxide fluxes were measured at the Lägeren CarboEurope IP flux site over the multi-species mixed forest dominated by European beech and Norway spruce. Measurements were carried out during a four-week period in October?November 2005 during leaf senescence. Fluxes were measured with a standard ultrasonic anemometer in combination with a quantum cascade laser absorption spectrometer that measured N2O, CO2, and H2O mixing ratios simultaneously at 5 Hz time resolution. To distinguish insignificant fluxes from significant ones it is proposed to use a new approach based on the significance of the correlation coefficient between vertical wind speed and mixing ratio fluctuations. This procedure eliminated roughly 56% of our half-hourly fluxes. Based on the remaining, quality checked N2O fluxes we quantified the mean efflux at 0.8 ± 0.4 ?mol m?2 h?1 (mean ± standard error). Most of the contribution to the N2O flux occurred during a 6.5-h period starting 4.5 h before each precipitation event. No relation with precipitation amount could be found. Visibility data representing fog density and duration at the site indicate that wetting of the canopy may have as strong an effect on N2O effluxes as does below-ground microbial activity. It is speculated that above-ground N2O production from the senescing leaves at high moisture (fog, drizzle, onset of precipitation event) may be responsible for part of the measured flux. In comparison with the annual CO2 budget of ?342 g C m?2 yr?1 it is estimated that concurrent N2O fluxes offset at least 5% of the greenhouse forcing reduction via net CO2 uptake

Metabolic profiles of six African cultivars of cassava (Manihot esculenta Crantz) highlight bottlenecks of root yield

Open Access Article; Published online: 17 Jan 2020Cassava is an important staple crop in sub‐Saharan Africa, due to its high productivity even on nutrient poor soils. The metabolic characteristics underlying this high productivity are poorly understood including the mode of photosynthesis, reasons for the high rate of photosynthesis, the extent of source/sink limitation, the impact of environment, and the extent of variation between cultivars. Six commercial African cassava cultivars were grown in a greenhouse in Erlangen, Germany, and in the field in Ibadan, Nigeria. Source leaves, sink leaves, stems and storage roots were harvested during storage root bulking and analyzed for sugars, organic acids, amino acids, phosphorylated intermediates, minerals, starch, protein, activities of enzymes in central metabolism and yield traits. High ratios of RuBisCO:phosphoenolpyruvate carboxylase activity support a C3 mode of photosynthesis. The high rate of photosynthesis is likely to be attributed to high activities of enzymes in the Calvin–Benson cycle and pathways for sucrose and starch synthesis. Nevertheless, source limitation is indicated because root yield traits correlated with metabolic traits in leaves rather than in the stem or storage roots. This situation was especially so in greenhouse‐grown plants, where irradiance will have been low. In the field, plants produced more storage roots. This was associated with higher AGPase activity and lower sucrose in the roots, indicating that feedforward loops enhanced sink capacity in the high light and low nitrogen environment in the field. Overall, these results indicated that carbon assimilation rate, the K battery, root starch synthesis, trehalose, and chlorogenic acid accumulation are potential target traits for genetic improvement

Quantized Rotation of Atoms From Photons with Orbital Angular Momentum

We demonstrate the coherent transfer of the orbital angular momentum of a photon to an atom in quantized units of hbar, using a 2-photon stimulated Raman process with Laguerre-Gaussian beams to generate an atomic vortex state in a Bose-Einstein condensate of sodium atoms. We show that the process is coherent by creating superpositions of different vortex states, where the relative phase between the states is determined by the relative phases of the optical fields. Furthermore, we create vortices of charge 2 by transferring to each atom the orbital angular momentum of two photons.Comment: New version, 4 pages and 3 figures, accepted for publication in Physical Review Letter

Relativistic Effects of Light in Moving Media with Extremely Low Group Velocity

A moving dielectric medium acts as an effective gravitational field on light. One can use media with extremely low group velocities [Lene Vestergaard Hau et al., Nature 397, 594 (1999)] to create dielectric analogs of astronomical effects on Earth. In particular, a vortex flow imprints a long-ranging topological effect on incident light and can behave like an optical black hole.Comment: Physical Review Letters (accepted