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To evaluate the dosimetric accuracy for small field proton irradiation relevant for pre-clinical in vivo studies using clinical infrastructure and technology. In this context additional beam collimation and range reduction was implemented.The clinical proton beam line employing pencil beam scanning (PBS) was adapted for the irradiation of small fields at shallow depths. Cylindrical collimators with apertures of 15, 12, 7 and 5mm as well as two different range shifter types, placed at different distances relative to the target, were tested: a bolus range shifter (BRS) attached to the collimator and a clinical nozzle mounted range shifter (CRS) placed at a distance of 72cm from the collimator. The Monte Carlo (MC) based dose calculation engine implemented in the clinical treatment planning system (TPS) was commissioned for these two additional hardware components. The study was conducted with a phantom and cylindrical target sizes between 2 and 25mm in diameter following a dosimetric end-to-end test concept.The setup with the CRS provided a uniform dose distribution across the target. An agreement of better than5% between the planned dose and the measurements was obtained for a target with 3mm diameter (collimator 5mm). A 2mm difference between the collimator and the target diameter (target being 2 mm smaller than the collimator) sufficed to cover the whole target with the planned dose in the setup with CRS. Using the BRS setup (target 8mm, collimator 12mm) resulted in non-homogeneous dose distributions, with a dose discrepancy of up to 10% between the planned and measured doses.The clinical proton infrastructure with adequate beam line adaptations and a state-of-the-art TPS based on MC dose calculations enables small animal irradiations with a high dosimetric precision and accuracy for target sizes down to 3mm.

The size distribution characteristics of the Saharan dust that is transported and deposited over many countries in the West African atmospheric environment (5°N) during the months of November to March, known locally as the Harmattan, have been determined over a 9-year period between 1996 and 2005, using a location in central Ghana (6° 40′N, 1° 34′W) as the reference geographical point. The particle size distributions and concentrations are discussed. Within the particle size range measured, the average inter-annual mass concentrations during the winter months ranged from 140 μg m − 3 to 1200 μg m − 3 while the average number concentrations varied between 24 cm − 3 and 63 cm − 3 . The measured particle concentrations outside the winter period were consistently less than 10 cm − 3 . The ground-based particle measuring equipment used did not provide for distinguishing the smoke fraction (due to bush fires and biomass burning) from the Saharan dust. These values therefore correspond to the total dust loads. The size range covered by the particle counter was 0.5 μm–25 μm. In spite of the strong daily and inter-annual variations in particle concentration, the overall dust mean particle diameter over the 9-year period was found to be 1.5 μm. The particle size distributions exhibited the typical distribution pattern for atmospheric aerosols with a coarse mode diameter situated at about 3.5 μm. The control exerted on the dust incursions and the particle concentrations by both the Inter-Tropical Convergence Zone (ITCZ) and the North Atlantic Oscillation (NAO) are highlighted. The experimental results reported in this study will be of value in validating satellite based observations and simulation models of the African dust plume during winter.

This paper presents the behaviour of aerosol size distributions and number concentrations with respect to specific meteorological conditions, deduced from experiments conducted over a period of 3 yr, in the Mediterranean coastal zone. Specific meteorological conditions, “East” wind and “Mistral” wind lead to specific size distributions and total number concentrations. In an “East” wind situation (steady winds, weak sunniness, high humidity), the size distributions are characterized by only accumulation and coarse particle modes. “Mistral” wind situations (gusty winds, strong sunniness, low humidity), lead to greater concentrations and the corresponding size distributions are often characterized by an Aitken peak but no accumulation peak. After a specific time-lag which depends on the particle size and meteorological conditions, the concentrations of coarse particles are well correlated with the wind velocity. In case of high “Mistral” winds, particles in the Aitken range and the wind velocity also are well correlated. It seems likely that the wind, by bursting small bubbles at the sea-air interface, is the major generation mechanism for these particles.

Three methods for prevention of perioperative spasm of the internal mammary artery were compared in 78 patients undergoing coronary artery bypass grafting. In group 1, internal mammary artery pedicles were divided distally, clamped, and placed under the upper sternum submerged in papaverine solution (1.5 mg/ml). In group 2, as in group 1 but before clamping, 2 ml of heparinized blood with 1.5 mg/ml papaverine added was injected into the vessel lumen. In group 3 treatment was as in group 2, but heparinized blood with papaverine was injected a second time just before extracorporeal bypass was begun. In a univariate analysis free flow from dilated internal mammary arteries was not significantly different among the groups (group 1, 58 ml/min; group 2, 82 ml/min; group 3, 68 ml/min; p < 0.1). When free flow from dilated internal mammary arteries was the dependent variable in a regression analysis, the use of intraluminal papaverine, high blood pressure during flow measurement, and high initial blood flow were predictors of high flow (all p < 0.01). Morphometric measurements on the resected distal portion of the dilated internal mammary arteries disclosed less folding of the internal elastic lamina and a larger luminal area in groups 2 and 3 compared with respective findings in group 1 (1.21 mm2 and 1.42mm2 versus 0.77 mm2; p < 0.02). Mechanical vessel wall injury occurred in 8 of 52 internal mammary arteries treated with intraluminal papaverine. Intraluminal papaverine solution injected once or twice in addition to external papaverine exposure therefore provides a better blood flow rate and distal dilation than mere submersion in papaverine solution, but at a considerable risk of mechanical wall injury. (J THORAC CARDIOVASC SURG 1995;110: 697-703)

The synthesis of a series of tricyclic quinoxalines is described. These compounds exhibit good affinity for both the strychnine-insensitive glycine site of the NMDA receptor and the AMPA receptor.

The design and synthesis of a bifunctional reagent, 1 , is described. This compound binds to beta-pleated sheet protein structures, while providing a complexation site for ferrous ion. These immobilized ions may be used to generate reactive, diffusible chemical species at or near the protein surface.

The first results of three campaigns of measurements of marine and atmospheric aerosols realised on the Mediterranean coast are presented. The data obtained by two particle counters and the chemical analysis of the aerosols are studied in relation to meteorological data. The number of particles collected and their chemical composition are linked to the direction and the speed of the wind.

A new optical probe has been designed, tested, calibrated and used in a bubbly two-phase flow. The probe is based on the principle of light scattering at an angle of ninety degrees from an incident laser beam. The errors inherent in such a technique are reviewed and evaluated. The calibration curve shows that the output voltage is proportional to the square of the bubble diameter. A first test is presented in a real bubbly flow produced by the action of wave-breaking in an air-sea interaction simulating facility.

Osmate(VI) esters chelated with optically active trans -N,N,N′ ,N′-tetramethyl-l,2-cyclohexanediamine are useful derivatives for enantiomeric identification of sub-milligram quantities of glycols by 1H NMR spectroscopy.

A series of 266 patients with closed renal injuries is presented. The majority (60 per cent) had minor injuries, without capsular tears or extension into the collecting system. None was operated upon for the renal injury and there was no death from the renal injury itself. Major injuries were recorded in 80 patients in whom there were capsular tears and/or extension into the collecting system. Of these, 33 were operated upon, with 3 deaths, all from associated injuries. The remaining 47 patients were not operated upon; 6 of these died, all from associated injuries. Gross injuries with shattered kidney or injury to the renal vessels were present in 19 patients (7 per cent), of whom 11 died, 8 from the renal injury. The diagnostic value of selective renal angiography is stressed. Injury to kidneys that were already diseased was rare but a renal sarcoma was missed. Non-function of the injured kidney was the commonest late complication and this occurred in 3 patients. Other late sequelae seemed to be very uncommon.

Acetylheliosupine, which has previously been isolated from Cynoglossum officinale and Myosotis sylvatica , is shown to be acetylated at the seco