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Definitive radiotherapy refers to delivery of large doses, typically 48-62 Gray, of ionizing radiation over several weeks using a daily or alternate-day fractionation schedule. The impact of definitive radiotherapy alone on haematopoiesis in tumour-bearing dogs is unknown. Medical records from 103 dogs receiving definitive 60Cobalt teletherapy for cancer over a 5-year period were reviewed for signalment, tumour type and location, total radiotherapy dose and fractionation scheme. Complete blood count data were collected before, halfway through, and at the end of radiation treatment, and analysed for changes associated with patient variables. The results demonstrate significant reductions in haematocrit, total white blood cell count, neutrophils, eosinophils, monocytes, lymphocytes and platelets occurred during definitive radiotherapy but remained within laboratory reference intervals. These data are important for anticipation of toxicity associated with combinations of radiotherapy and chemotherapy in dogs but do not support the routine monitoring of haematology parameters during definitive radiotherapy. [ABSTRACT FROM AUTHOR]

A model for predicting the accumulated rotation of stiff piles under random two-way loading is presented. The model is based on a strain superposition rule similar to Miner's rule and uses rainflow-counting to decompose a random time-series of varying loads into a set of simple load reversals. The method is consistent with the work of LeBlanc (2010) and is supported by 1 laboratory tests. An example is given for an offshore wind turbine indicating that accumulated pile rotation during the life of the turbine is dominated by the worst expected load. [ABSTRACT FROM AUTHOR]

The driven monopile is currently the preferred foundation type for most offshore wind farms. While the static capacity of the monopile is important, a safe design must also address issues of accumulated rotation and changes in stiffness after long-term cyclic loading. Design guidance on this issue is limited. To address this, a series of laboratory tests were conducted where a stiff pile in drained sand was subjected to between 8000 and 60 000 cycles of combined moment and horizontal loading. A typical design for an offshore wind turbine monopile was used as a basis for the study, to ensure that pile dimensions and loading ranges were realistic. A complete non-dimensional framework for stiff piles in sand is presented, and applied to interpret the test results. The accumulated rotation was found to be dependent on relative density, and was strongly affected by the characteristics of the applied cyclic load. Particular loading characteristics were found to cause a significant increase in the accumulated rotation. The pile stiffness increased with number of cycles, which contrasts with the current methodology where static load-displacement curves are degraded to account for cyclic loading. Methods are presented to predict the change in stiffness and the accumulated rotation of a stiff pile due to long-term cyclic loading. The use of the methods developed is demonstrated for a typical full-scale monopile. [ABSTRACT FROM AUTHOR]

Résumé Nous rapportons l’observation d’un érythème pigmenté fixe bulleux à l’hydroxyzine et réactivité croisée avec les dérivés de la pipérazine chez une femme de 72 ans. La patiente présentait une apparition récente de bulles flasques sur fonds érythémateux des mains, des pieds et du flanc. Des macules pigmentées arrondies de grande taille étaient notées. Le diagnostic d’érythème pigmenté fixe bulleux était évoqué. Le seul médicament introduit récemment était l’hydroxyzine. À l’interrogatoire, il y avait plusieurs épisodes similaires après la prise de fluoroquinolones et d’antihistaminiques (levocétirizine et cétirizine) ; la loratadine et la desloratadine étaient bien tolérées. L’histologie montrait des nécroses kératinocytaires compatibles avec un érythème pigmenté fixe bulleux. Les tests épicutanés réalisés avec l’hydroxyzine, la cétirizine, la levocétirizine et les fluoroquinolones (concentration à 30 % dans l’eau et dans la vaseline) étaient négatifs aux lectures successives à 48, 72 et 96 heures tant au niveau des séquelles pigmentées qu’au niveau de la peau saine. Le diagnostic d’un érythème pigmenté fixe bulleux à ces différentes molécules était tout de même retenu et une carte contre-indiquant ces molécules était remise à la patiente. Quelques mois plus tard, une prise accidentelle de levocétirizine avant la réalisation d’un scanner avec injection provoquait une nouvelle poussée bulleuse de toutes les lésions séquellaires de l’érythème pigmenté fixe. We report a case of hydroxyzine-induced fixed drug eruption and cross-reactivity with piperazine derivatives. A 72-year-old woman presented with a recent onset of flaccid bullae over erythematous patches on her hands, feet and back; large rounded pigmented patches were noted. A diagnosis of bullous fixed drug eruption was raised. The only drug she began taking recently was hydroxyzine. Her past medical history included similar episodes after taking fluoroquinolones and antihistamines (levocetirizine and cetirizine); desloratadine and loratadine had been well tolerated. A histological examination of her skin showed keratinocyte necrosis compatible with a bullous fixed drug eruption. Patch-tests performed with hydroxyzine, cetirizine, levocetirizine and fluoroquinolones (concentration at 30% in water and in vaseline) were negative in successive readings at 48, 72 and 96 hours, both in pigmented scars and in healthy skin. These diverse molecules were nevertheless held responsible for the bullous fixed drug eruptions. For this reason, a document listing these drugs as contraindicated was given to the patient. A few months later, the fortuitous injection of levocetirizine before having a CT scan caused a new bullous eruption, with all the typical lesions of a fixed drug eruption. [ABSTRACT FROM AUTHOR]

This paper presents a summary of the measurements that were made during the heavily-instrumented Reactive Halogens in the Marine Boundary Layer (RHaMBLe) coastal study in Roscoff on the North West coast of France. It was clearly demonstrated that iodine-mediated coastal particle formation occurs, driven by daytime low tide emission of molecular iodine, I2, by macroalgal species fully or partially exposed by the receding waterline. Ultrafine particle concentrations strongly correlate with the rapidly recycled reactive iodine species, IO, produced at high concentrations following photolysis of I2. The heterogeneous macroalgal I2 sources lead to variable relative concentrations of iodine species observed by path-integrated and in situ measurement techniques. Apparent particle emission fluxes were associated with an enhanced apparent depositional flux of ozone, consistent with both a direct O3 deposition to macroalgae and involvement of O3 in iodine photochemistry and subsequent particle formation below the measurement height. The magnitude of the particle formation events was observed to be greatest at the lowest tides with higher concentrations of ultrafine particles growing to much larger sizes, probably by the condensation of anthropogenically-formed condensable material. At such sizes the particles should be able to act as cloud condensation nuclei at reasonable atmospheric supersaturations. [ABSTRACT FROM AUTHOR]

Time profiles of molecular iodine emissions from seven species of seaweed have been measured at high time resolution (7.5 s) by direct spectroscopic quantification of the gas phase I2 using broadband cavity enhanced absorption spectroscopy. Substantial differences were found between species, both in the amounts of I2 emitted when the plants were exposed to air and in the shapes of their emission time profiles. Two species of kelp, Laminaria digitata and Laminaria hyperborea, were found to be the most potent emitters, producing an intense burst of I2 when first exposed to air. I2 was also observed from Saccharina latissima and Ascophyllum nodosum but in lower amounts and with broader time profiles. I2 mixing ratios from two Fucus species and Dictyopteris membranacea were at or below the detection limit of the present instrument (25 pptv). A further set of experiments investigated the time dependence of I2 emissions and aerosol particle formation when fragments of L. digitata were exposed to desiccation in air, to ozone and to oligoguluronate stress factors. Particle formation occurred in all L. digitata stress experiments where ozone and light were present, subject to the I2 mixing ratios being above certain threshold amounts. Moreover, the particle number concentrations closely tracked variations in the I2 mixing ratios, confirming the results of previous studies that the condensable particle-forming gases derive from the photochemical oxidation of the plant's I2 emissions. This work also supports the theory that particle nucleation in the coastal atmosphere occurs in "hot-spot" regions of locally elevated concentrations of condensable gases: the greatest atmospheric concentrations of I2 and hence of condensable iodine oxides are likely to be above plants of the most efficiently emitting kelp species and localised in time to shortly after these seaweeds are uncovered by a receding tide. [ABSTRACT FROM AUTHOR]

Emissions from the dominant six macroalgal species in the coastal regions around Rosccoff, France, have been modelled to support the Reactive Halogens in the Marine Boundary Layer Experiment (RHaMBLE) campaign undertaken in September 2006. A 2-D model was used to explore the relationship between point and line measurements of molecular iodine concentrations, and total regional emissions, based on seaweed I2 emission rates measured in the laboratory. The relatively simple modelling technique has produced modelled point and line data, which compare quantitatively with campaign measurements, and provide a link between emission fields and the different measurement geometries used to quantify atmospheric I2 concentrations during RHaMBLE. During nightime, absolute concentrations in the region of 5 pptv are predicted and measured in the LP-DOAS measurements, with site concentrations predicted and measured up to 40 pptv, compatible with concentrations above Laminariales beds of approximately 2.5 ppbv. Daytime measured concentrations of I2 at site correlate with modelled production and transport processes, however complete recycling of photodissociated I2 is required in the model to quantitatively match measured concentrations. Additional local source terms are suggested to provide a feasible mechanism to account for this discrepancy. Total of I2 emissions over the 100 km² region around Roscoff are calculated as 1.5×1019 molecules per second during the lowest tides. [ABSTRACT FROM AUTHOR]