[en] The number of transcatheteral occulsion of abdominal arteries reported so far enables us to differentiate between complications, which are specific for the methods used, or which are organ-specific and material-specific. Among the complications specific for the methods concerned are: complications occuring in angiography; tumour embolism in the lung; transport of embolic material into the lung; transport of embolic material into the arteries of the lower half of the body; renal insufficiency; necrosis; and, finally, abscess formation. Among the organ-specific complications are: necrosis (especially of the spleen and in the operated upper gastro-intestinal tract); abscess formation (spleen, kidneys, liver); retroperitoneal phlegmones (kidney); relapsing haemorrhages (gastro-intestinal tract, kidneys); renal insufficiency (in case of pre-existing renal damage); hypertension (described so far as transient blood pressure increase only); hypertensive crisis (after renal artery occulsion for malignant hypertension); hepatic insufficiency and gallbladder infarction (in embolisation of the liver); transport of embolic material into adjacent arteris (in case of embolisation, into the vessels of the truncus coeliacus); and, finally, hypoglycaemia (in embolisation of the liver). Among the material-specific complications are: adhesion of the catheter tip to the vascular wall (Bucrylate); dislocation of Gianturco's spiral; allergic (anaphylactic) reaction to the embolic material (not described so far); recanalisation (in case of absorbable substances such as Fibrospum and Gelfoam); substitutive blood supply via the formation or extension of collaterals; necrosis in peripherally (capillary) occluding substances such as Bucrylate and Ethibloc; and, finally, abscess formation (in case of non-sterile embolic material). Some of these complications can be classified under more than one category. (orig./APR)

No abstract available

[en] The KTeV experiment at Fermilab is nearing the end of a year-long run to collect data on CP violation and rare kaon decays. I report on the status of this run and present preliminary results from several of the decay modes under study. A total of 5.7 million (before offline cuts) decays of the Re(ε^'/ε) statistics-limiting K_L⁰→π⁰π⁰ mode were collected. A search for light supersymmetric particles yielded a null result, excluding the existence of the R⁰ (gg) over a mass range of 1.2→4.6GeV/c² and a lifetime range of 2x10^-10→7x10^-4 seconds. I report on the first observation of the decay K_L⁰→π⁺π^-e⁺e^-, along with a preliminary branching ratio for this decay of (2.6±0.5)x10^-7. Finally, I report on an improved (preliminary) upper limit on the branching ratio for K_L⁰→π⁰ν bar ν of 1.8x10^-6 (90% c.l.). copyright 1997 American Institute of Physics

[en] We present here the results of new searches for anisotropy within the HiRes data set, including both monocular and stereo events with energies exceeding 1 EeV. We include the results of searches for pointlike excesses, including correlations with BL-Lacertae objects, as well as extended sources and dipole moments in the full-sky survey

[en] Anomalous defect interaction and amorphization of silicon crystals irradiated with 2 MeV Si⁺ beams are studied by transmission electron microscopy and optical reflection measurements. The results of these investigations show that the dose dependence of the defect production at irradiation temperatures above 400 K is determined by extreme defect interaction processes resulting in recombination and cluster formation of point defects (5 x 10₁₃ to 5 x 10₁₅ cm^-₂) and formation of stacking faults and dislocations (5 x 10₁₅ to 3 x 10₁₇ cm^-₂). The final amorphization represents a new mechanism originating from a dense dislocation network

[en] We present an overview of the most recent results from the High-Resolution Fly's Eye (HiRes) observatory. These include both monocular and stereo energy spectra, the results of a search for correlations between event arrival directions and active galactic nuclei, and new results on composition studies using airshower maximum.

[en] We report on the analysis of the rare decay K_L→μ⁺μ^-γ the 1997 data from the KTeV experiment at Fermilab. A total of 9327 candidate events are observed with 2.4% background, representing a factor of 40 increase in statistics over the current world sample. We find that B(K_L→μ⁺μ^-γ)=(3.62±0.04_stat±0.08_syst) x 10^-7. The form factor parameter α_K^* is measured to be α_K^*=-0.160^+0.026_-0.028. In addition, we make the first measurement of the parameter α from the D'Ambrosio-Isidori-Portoles form factor, finding α=-1.54±0.10. In that model, this α measurement limits the Cabibbo-Kobayashi-Maskawa parameter ρ>-0.2

[en] We report on a study of the decay K_L->e⁺e^-γγ carried out as a part of the KTeV/E799 experiment at Fermilab. The 1997 data yielded a sample of 1543 events, including an expected background of 56±8 events. An effective form factor was determined from the observed distribution of the e⁺e^- invariant mass. Using this form factor in the calculation of the detector acceptance, the branching ratio was measured to be B(K_L->e⁺e^-γγ,E_γ^*>5MeV)=(5.84±0.15(stat)±0.32(syst))x10^-7.

[en] We report on the first observation of the decay K_L→π⁰e⁺e^- γ by the KTeV E799 experiment at Fermilab. Based upon a sample of 48events with an estimated background of 3.6±1.1 events, we measure the K_L→π⁰e⁺e^- γ branching ratio to be (2.34±0.35±0.13) x 10^-8 . Our data agree with recent O(p⁶) calculations in chiral perturbation theory that include contributions from vector meson exchange through the parameter a_V . A fit was made to the K_L→π⁰e⁺e^- γ data for a_V with the result -0.67±0.21±0.12 , which is consistent with previous results from KTeV

[en] We observe 441 K_L->e⁺e^-e⁺e^- candidate events with a background of 4.2events and measure B(K_L->e⁺e^-e⁺ e^-)=[3.72±0.18(stat )±0.23(syst)]x 10^-8 in the KTeV/E799II experiment at Fermilab. Using the distribution of the angle between the planes of the e⁺e^- pairs, we measure the CP parameters β_CP=-0.23±0.09(stat )±0.02(syst) and γ_CP=-0.09±0.09(stat )±0.02(syst) . We also present the first detailed study of the e⁺e^- invariant mass spectrum in this decay mode