FD-TD calculation with composite materials. Application to C160 aircraft measurements

In a frequency domain in which a material thickness is smaller than the skin depth, a formalism based on the sheet impedance concept was developed and introduced in the FD-TD (finite difference-time domain) code ALICE. The predictive capabilities of the 3D code was evaluated by comparison to analytical and experimental data. The following subject areas are covered: low frequency electromagnetic penetration of loaded apertures; FD-TD modeling; and in-flight experiment modeling

FD-TD numerical simulation of an entire lightning strike on the C160 aircraft

Experimental transient electromagnetic field measurements were performed on a Transall C160 aircraft during in-flight lightning strikes. The data allow a test of the predictive capabilities of a three dimensional time domain finite difference code (ALICE) developed at ONERA in order to investigate lightning-aircraft interactions. Using a transfer function technique in the 3D code, it is shown that a bi-leader attached to an aircraft can be simulated by a linear model, and so the electromagnetic fields can be calculated anywhere on the vehicle. Comparison of experimental and numerical results were made for several lightning strikes. Skin current density and electromagnetic field distributions are discussed in detail

Impact of sheep grazing on juvenile sea bass, Dicentrarchus labrax L., in tidal salt marshes

The diet of young of the year sea bass, Dicentrarchus labrax L., from sheep grazed and ungrazed tidal salt marshes were com-pared qualitatively and quantitatively in Mont Saint-Michel Bay. In areas without grazing pressure, the vegetation gradient changes from a pioneer Puccinellia maritima dominated community at the tidal ¯at boundaries through a Atriplex portulacoides dominated community in the middle of the marsh to a mature Elymus pungens dominated community at the landward edge. The A. portula-coides community is highly productive and provides important quantities of litter which provides a habitat and good supply to substain high densities of the detrivorous amphipod Orchestia gammarellus. In the grazed areas, the vegetation is replaced by P. maritima communities, a low productive grass plant, and food availability and habitat suitability are reduced for O. gammarellus. Juvenile sea bass colonise the salt marsh at ¯ood during 43% of the spring tides which inundate the salt marsh creeks. They forage inside the marsh and feed mainly on O. gammarellus in the ungrazed marshes. In grazed areas, this amphipod is replaced by other species and juvenile sea bass consume less food from the marsh. This illustrates a direct effect of a terrestrial herbivore on a coastal food web, and suggests that management of salt marsh is complex and promotion of one component of their biota could involve reductions in other species

Lethal junctional epidermolysis bullosa in heavy horses in France

Cinq cas d’épidermolyse huileuse jonctionnelle léthale ( Epitheliogenesis imperfecta ) ont été diagnostiqués au début de l’année 1989 dans deux races de cheval de trait en France. Les études anatomo-cliniques, ultra-structurales et génétiques montrent qu’il s'agit d’une affection héréditaire à déterminisme autosomal récessif analogue à l’épidermolyse huileuse jonctionnelle léithale décrite par Herlitz chez l'homme car le clivage de la jonction dermo-épidermique se situe au- dessus de la basale, au sein de la Lamina lucida. Il s’agit des premiers cas de cette maladie décrits chez le cheval en France.Five cases of junctional epidermolysis bullosa ( Epitheliogenis imper fecta) have been diagnosed since the beginning of 1989 in two draught- horse breeds in France. Anatomo-clinical, ultrastructural and genetic studies indicate that it is an hereditary disease due to an autosomal recessive gene similar to the lethal form of junctional epidermolysis bullosa descri bed by Herlitz in the child, as the cleft of the dermo-epidermal junction is located under the basal membrane, in the Lamina lucida. These are the first cases of this disease described in France in the horse

Educational needs of health professionals working in rheumatology in Europe

Objective: To explore the availability of postgraduate education for health professionals (HPs) working in rheumatology in Europe, and their perceived educational needs and barriers for participation in current educational offerings. Methods: Structured interviews were conducted with national representatives of rheumatology HPs’ organisations and an online survey among individual HPs was disseminated through existing EULAR networks (10 languages including English). These comprised questions on: availability of postgraduate education, familiarity with EULAR and its educational offerings, unmet needs regarding the contents and mode of delivery and potential barriers to participate in education (0-10 scales). Results: According to 17 national representatives, postgraduate rheumatology education was most common for nurses, physical and occupational therapists. There were 1041 individual responses to the survey, of whom 48% completed all questions. More than half (56%) were familiar with EULAR as an organisation, whereas less than 25% had attended the EULAR congress or was familiar with EULAR online courses. Educational needs regarding contents were highest for “inflammatory arthritis” and “connective tissue diseases” and regarding modes of delivery for “courses organised in own country” and “online courses”. Important barriers to participation included lack of “resources”, “time” and “English language skills”. Overall, there was considerable variation in needs and barriers among countries . Conclusions: There is a lack of postgraduate rheumatology education for HPs in most countries. There are opportunities to raise awareness regarding EULAR educational offerings and to develop courses provided in HPs’ own country, tailored to national needs and barriers and taking language barriers into consideration

Concomitant sinus histiocytosis with massive lymphadenopathy (Rosai-Dorfman Disease) and diffuse large B-cell lymphoma: a case report

IntroductionSinus histiocytosis with massive lymphadenopathy, also known as Rosai-Dorfman Disease, is a rare and benign source of lymphadenopathy first described in 1969, which mimics neoplastic processes. This disease commonly presents in children and young adults with supra-diaphragmatic lymphadenopathy or extranodal lesions consisting of tissue infiltrates composed of a polyclonal population of histiocytes. Since its description greater than 400 cases have been described, sometimes in patients with a variety of treated and untreated neoplastic diseases. However, the literature contains reports of only 19 cases of Rosai-Dorfman Disease in association with lymphomas, Hodgkin's or non-Hodgkin's. The majority of these cases have the two diagnoses, malignant lymphoma and Rosai-Dorfman Disease, separated in time. Interestingly, infradiaphragmatic lymphadenopathy was a feature in the majority of previously reported cases of Rosai-Dorfman Disease and non-Hodgkin's lymphoma.Case presentationThis report provides details of a case with co-existing sinus histiocytosis with massive lymphadenopathy and diffuse large B cell non-Hodgkin's lymphoma. This case is the fifth described case of simultaneous Rosai-Dorfman Disease and concurrent non-Hodgkin's lymphoma. Unfortunately, the diagnosis of a clinically aggressive diffuse large B cell lymphoma was made at autopsy. The aggressive biological behavior of the diffuse large B cell lymphoma in this patient may have been related to the underlying immune dysregulation believed to be part of the pathophysiology of Rosai-Dorfman Disease.ConclusionTaken together this report and the preceding reports of Rosai-Dorfman Disease and non-Hodgkin's lymphoma suggests that in cases with a diagnosis of Rosai-Dorfman Disease in the setting of prominent infradiaphragmatic lymphadenopathy, clinicians should maintain a high index of suspicion for the presence of occult non-Hodgkin's lymphoma especially if the clinical course is atypical for classic Rosai-Dorfman Disease