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Notes: A kinetic Monte Carlo method has been developed for the simulation of interfacecontrolled solid-state transformations to overcome timescale limitations associated with otheratomistic simulation methods. In the simulation method the atoms can take place on sites from(at least) two intertwining crystal lattices. To enable the atoms to also take positions betweenthe ideal lattice sites, a collection of randomly placed sites can be included. These ‘randomsites’ have a realistic chance to be occupied at the location of the transformation interface andthus allow for irregularities in the atomic structure of the transformation interface. The atomsmove by independent, thermally activated jumps. The activation energy for the atomic jumpscan be determined for every jump separately based on the arrangement of the neighbouringatoms. The simulation method has been used to study the interface mobility in the austenite toferrite transformation in iron for different interface orientations. The results obtained indicatethat the excess volume associated with the interface plays a key role for the activation enthalpyfor the interface mobility. The rate controlling process is the rearrangement of free space at theinterface by series of (unfavourable) jumps by different atoms to create a path from the parentto the product phase

Notes: Abstract The hydrozoans Maeotias inexspectata Ostroumoff, 1896 and Blackfordia virginica Mayer, 1910, believed to be native to the Black Sea (i.e. Sarmatic) and resident in a variety of estuarine habitats worldwide, were found as introduced species in the Petaluma River and Napa River, California, in 1992 and 1993. These rivers are mostly-estuarine tributaries that flow into north San Francisco Bay. Both species appeared to be well-established in this brackishwater habitat. Salinities at the collection sites were about 11‰ during the summer, rising to nearly 20‰ in the early autumn and falling to near 0‰ in the winter. Large numbers of all sizes of both species of medusae were observed and collected, indicating that the hydroid stages of the life cycles of the two are also well-established in these rivers. In the Petaluma River, populations of both species were at maximum in late July, with numbers of individuals declining through August and into September; the Napa River was sampled only in October, and at that time only B. virginica was found. Examination of full guts of M. inexspectata and B. virginica medusae revealed that both species had fed nearly exclusively on small crustaceans, principally barnacle nauplii, copepods and their eggs and nauplii, and crab zoea larvae (M. inexspectata only). All the M. inexspectata medusae were males, indicating that the population has probably developed from the introduction of perhaps only a single male polyp or polyp bud. In spite of its inability to reproduce sexually, this population appears to be maintained by the prodigious ability of the polyp to bud and reproduce asexually, and is fully capable of invading additional low-salinity habitats from its present Petaluma River site. Male and female B. virginica medusae were collected in both the Petaluma River and the Napa River, indicating that B. virginica may have been introduced by either the polyp or medusa stage (or both), but that multiple individuals (of both sexes) must have arrived from another port in one or more invasions. As indicated for M. inexspectata, the B. virginica population will also probably seed new populations in San Francisco Bay and elsewhere. Based on its cnidome as well as the morphology of both medusa and polyp, M. inexspectata has been reclassified by moving it from the family Olindiidae, Limnomedusae, to the family Moerisiidae, Anthomedusae.

Notes: Summary  A 68-year old patient presented with increasing right-sided weakness, dysarthria, pyrexia and a deteriorating general condition. CT and MRI showed about 20 round hyperdense lesions with peripheral enhancment of contrast material up to 1.5 cm in diameter.  Antibiotic triple-therapy using ceftriaxone, gentamycin and metronidazole for 39 days and followed by antibiotic double-therapy using ceftriaxone and metronidazole for a further 22 days resulted in a radiologically proven reduction of the abscesses to very small remnants which disappeared completely during the follow-up period of two years. Simultaneously the general condition of the patient improved significantly. Repeated attempts at isolation of bacteria, fungi, protozoa and parasites from a subdural empyema failed, The histological examination of an abscess, which was entirely removed on occipital craniotomy, showed a structure resembling actinomycosis.

Notes: SUMMARY 1. Negative effects of zooplankton on the availability of phosphorus (P) for phytoplankton as a result of the retention of nutrients in zooplankton biomass and the sedimentation of exoskeletal remains after moulting, have been recently proposed.2. In a mesocosm study, the relative importance of these mechanisms was tested for the freshwater cladoceran Daphnia hyalina×galeata. A total of 13 mesocosm bags was suspended in a mesotrophic German lake during summer 2000 and fertilised with inorganic P in order to obtain a total nitrogen to total P ratio closer to the Redfield ratio. D. hyalina×galeata was then added at a logarithmically scaled density gradient of up to 40 ind. L−1. Zooplankton densities, dissolved inorganic, particulate organic (seston 〈100 μm), as well as total nutrient concentrations were monitored. Additionally, nutrient concentrations of sediment water removed from the bottom of the mesocosm bags via a manual pump were determined.3. Seston carbon (C), seston P and total P were significantly negatively correlated with Daphnia densities. The amount of particulate P (∼5–6 μg P L−1) sequestered from the seston compartment by Daphnia corresponded roughly to the increase of zooplankton biomass (population growth). Soluble reactive phosphorous (SRP) was at all times high (∼25–35 μg P L−1) and possibly unavailable to phytoplankton as a result of P adsorption to calcite during a calcite precipitation event (whiting). P concentrations determined in sediment water were generally 〈60 μg P m−2 and thus never exceeded 1% of the total amount of P bound in particulate matter of the overlying water column.4. Seston C : P ratios followed a polynomial second-order function: At Daphnia densities 〈40 ind. L−1 a positive linear relationship was evident, which is explained by the stronger reduction of P compared with C in seston, and transfer of seston P to zooplankton. Highest seston C : P ratios of ∼300 : 1 were observed at Daphnia densities of ∼30–50 ind. L−1, which is in agreement with proposed threshold values limiting Daphnia reproductive growth. At Daphnia densities 〉40–50 ind. L−1 C : P ratios were decreased because of the strong reduction of seston C at close to constantly low seston P-values of ∼3–4 μg P L−1.5. At least for Daphnia, it may be concluded that – unlike population growth – the sedimentation of faecal pellets and carapaces after moulting seem negligible processes in pelagic phosphorus dynamics.