Generic Syzygy Schemes

For a finite dimensional vector space G we define the k-th generic syzygy scheme Gensyz_k(G) by explicit equations. We show that the syzygy scheme Syz(f) of any syzygy in the linear strand of a projective variety X which is cut out by quadrics is a cone over a linear section of a corresponding generic syzygy scheme. We also give a geometric description of Gensyz_k(G) for k=0,1,2. In particular Gensyz_2(G) is the union of a Pl"ucker embedded Grassmannian and a linear space. From this we deduce that every smooth, non-degenerate projective curve C which is cut out by quadrics and has a p-th linear syzygy of rank p+3 admits a rank 2 vector bundle E with det E = O_C(1) and h^0(E) at least p+4.Comment: 12 Pages. This paper is a completely rewritten version of the first part of math.AG/0108078. It also contains several new result

Stress in seamen and non seamen employed by the same company

Objectives: The aim of this survey was to compare the level of professional stress among seamen – crew members - who work on French oceanographic vessels to the one of technicians and engineers from the oceanographic institute, who board the ships to operate special equipment during sea voyages. Results: two groups of subjects were included: 74 seamen and 74 non seamen, males of comparable ages were questioned. Results showed that there was no significant difference in strain at work and social support between them (41 seamen and 50 non seaman professionals who filled in the questionnaires). There was a very significant difference in the decision latitude: much lower level for seamen as compared to non seamen. 17% compared to zero percent of non seamen were ranked in the heavy strain/low decision latitude category regarded by Karasek as a high risk of stress (compared to 0% of non seaman professionals). 33% of seamen in this group reached a score that indicated psychical stress according to Langner’s total health test. Conclusion: The results of the survey show that the occupation of seamen includes specific elements regarded by Karasek as leading to a risk of stress. Method: Two questionnaires were used for collecting data: - Langner’s total health test (22 items) that investigates the level of psychical stress, - Karasek’s "Job Content Questionnaire" (38 items) used for investigation of strain at work, psychological pressure, decision latitude and social support. Data were processed by a statistical software : Sphinx, using Chi² test. Results: two groups of subjects were included: 74 seamen and 74 non seamen, males of comparable ages were questioned. Results showed that there was no significant difference in strain at work and social support between them (41 seamen and 50 non seaman professionals who filled in the questionnaires). There was a very significant difference in the decision latitude: much lower level for seamen as compared to non seamen. 17% compared to zero percent of non seamen were ranked in the heavy strain/low decision latitude category regarded by Karasek as a high risk of stress (compared to 0% of non seaman professionals). 33% of seamen in this group reached a score that indicated psychical stress according to Langner’s total health test. Conclusion: The results of the survey show that the occupation of seamen includes specific elements regarded by Karasek as leading to a risk of stress

Skin infection by Staphylococcus aureus in a fisherman: difficulty in continuing work on board

Background and aim: The aim of this study was to understand why an infectious skin disease due to colonisation by Staphylococcus aureus methi-S led to disembarkation of a fisherman for treatment and follow-up.Materials and methods: While discussing this case we have analysed different reasons why the studied fisherman could not be successfully treated on board.Results: A 42-year-old fisherman was first presented with skin lesions while fishing for hake. When the fisherman had developed a fever and exfoliative skin lesions on both hands, the ship’s captain called the radio-medical centre for the maritime consultation in Toulouse and for the advice on treatment. After 3 days on penicillin, the fever decreased, but the dermatitis became incapacitating. On his return to shore, the fisherman was hospitalised. Bacteriological swabs of the skin lesion showed colonisation with Staphylococcus aureus methi-S with presence of Panton Valentine leukocidin. Seven-day treatment witha follow-up of antibioticotherapy was necessary to resolve the skin eruption and obtain definitive apyrexia. Treatment ashore was advised because of difficulty in continuing manual work on board whilst suffering from significant skin lesions and also due to fear of contagion.Conclusions: Skin infection with Staphylococcus aureus methi-S with presence of Panton Valentine leukocidinis difficult to treat on board because of difficulty in carrying out manual work when hands are affected, and also due to slow improvement of dermatitis even when appropriate treatment is undergone. The maritime environment is also a risk factor for skin abrasion, which can lead to secondary colonisation of pathogenic bacteria

Syzygies of torsion bundles and the geometry of the level l modular variety over M_g

We formulate, and in some cases prove, three statements concerning the purity or, more generally the naturality of the resolution of various rings one can attach to a generic curve of genus g and a torsion point of order l in its Jacobian. These statements can be viewed an analogues of Green's Conjecture and we verify them computationally for bounded genus. We then compute the cohomology class of the corresponding non-vanishing locus in the moduli space R_{g,l} of twisted level l curves of genus g and use this to derive results about the birational geometry of R_{g, l}. For instance, we prove that R_{g,3} is a variety of general type when g>11 and the Kodaira dimension of R_{11,3} is greater than or equal to 19. In the last section we explain probabilistically the unexpected failure of the Prym-Green conjecture in genus 8 and level 2.Comment: 35 pages, appeared in Invent Math. We correct an inaccuracy in the statement of Prop 2.

Retroperitoneal Pelvic Solitary Fibrous Tumor With High Tracer Uptake in 68Ga-DOTATOC PET/CT: A Rare Differential Diagnosis of Paraganglioma.

International audienceWe report the case of a 27-year-old woman referred to our department for the characterization of a 7 × 6-cm left ischio-anal fossa mass by Ga-DOTATOC PET/CT. Several diagnoses were previously mentioned, in particular, myxoid sarcoma but also pelvic paraganglioma. Urinary methoxylated derivates and blood chromogranin A tests were negative. PET/CT showed a high Ga-DOTATOC uptake of the mass that was strongly consistent with paraganglioma diagnosis. Histopathological analysis surprisingly revealed a solitary fibrous tumor without aggressive criteria