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Survival and growth of the native oyster Crassostrea gasar along the juvenile and adult phases were evaluated in three different stocking densities [low (D), medium (2D) and high (3D)] and in two grow-out systems (fixed and floating system). The fixed system consisted of a rack made with PVC, fixed from the bottom with wood sticks. The floating system consisted of floating bags suspended by a rack made with PVC and maintained submerged from the seawater surface by eight floats. Survival and shell height of oysters cultured after 30, 60 and 90 days were registered in each phase and in each grow-out system. Results showed that the grow-out system did not affect survival and growth of C. gasar in the juvenile and adult phases. The tested densities affected the survival of oysters cultured over time in both phases but did not affect oyster growth. At times analyzed, it was observed positive growth in juvenile oysters grow after 90 days of culture. However, in the adult phase, no growth was observed after 90 days of culture. Oyster yield was higher in the density 3D, in both juvenile and adult phases. These findings contributed to the development of the oyster C. gasar culture.(AU)

A sobrevivência e o crescimento da ostra nativa Crassostrea gasar nas fases juvenil e adulta foram avaliados sob três diferentes densidades de estocagem [baixa (D), média (2D) e alta (3D)] e dois sistemas de engorda (fixo e flutuante). O sistema fixo consistiu em uma mesa de PVC, fixada na parte inferior com varas de madeira. O sistema flutuante consistiu em travesseiros flutuantes suspensos por uma mesa de PVC e mantidas submersas da superfície da água do mar por oito flutuadores. Registraram-se sobrevivência e altura da concha de ostras cultivadas após 30, 60 e 90 dias, em cada fase (juvenil e adulta) e em cada sistema (fixo e flutuante). Os resultados mostraram que o sistema de engorda não afetou a sobrevivência e o crescimento de C. gasar nas fases juvenil e adulta. As densidades testadas afetaram a sobrevivência das ostras ao longo do tempo, em ambas as fases, mas não afetaram o crescimento em altura. Nos tempos analisados, ostras juvenis apresentaram crescimento após 90 dias de cultivo. Porém, na fase adulta, não foi observado crescimento após 90 dias de cultivo. A produção de ostras, foi maior na densidade 3D, nas fases juvenil e adulta. Os presentes achados contribuíram para o desenvolvimento do cultivo da ostra C. gasar.(AU)

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The project MONARPOP analysed the concentrations of semivolatile organic compounds (SVOCs) in two important sink compartments, needles of Norway spruce (Picea abies [L.] Karst.) and forest soil from 40 remote Alpine forest sites in Austria, Germany, Italy, Slovenia and Switzerland. In the present study the load of PCDD/F, PCB, PBDE, PAH, HCB, HCH and DDT in the Alps calculated on the basis of measured data are compared with their estimated emissions in the Alpine region. It comes out that the masses of the studied pollutants stored in the forests are higher than the corresponding emissions in the Alpine area indicating that the Alps are a sink for POPs advected from surrounding areas. It is assumed that local emissions of PCDD/F and PAH deriving from biomass burning are probably underestimated and that the pool of these pollutants in the forests represents the accumulation over some decades.

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Glasgow Coma Scale (GCS) scores on admission may be predictors of outcome in patients with brain injuries. This study correlated the outcomes of children with traumatic brain stem lesions with their initial GCS scores and morphological patterns of injury as shown on computed tomography (CT) or magnetic resonance (MR) imaging. During the last 16 years, we have treated 1,108 children with brain injuries. The entire series included only 21 (1.9%) children who had clinical signs of brain stem lesions with morphological correlates on CT or MR imaging. Clinical findings were assessed according to the GCS and compared with scores on the Glasgow Outcome Scale (GOS). Of these 21 children, 16 (76%) had morphological lesions seen on CT scans. In 5 (24%) of the children only the MR images revealed brain stem lesions and their CT scans were negative. Generalized severe brain swelling was present in 6 cases (28%). There was a significant difference in GOS scores between patients with initial GCS scores of 3 and 4 and those with GCS scores between 5 and 7 (P < 0.02). Children with intracranial pressure higher than 40 mmHg had poorer outcomes than patients whose intracranial pressure was lower, but the differences were not significant. Outcome did not correlate significantly with morphological patterns of injury or the presence of extracranial injuries. The GCS is a reliable indicator of severity of injury and of outcome in children with brain stem injuries. MR imaging was more sensitive than CT in detecting brain stem lesions.

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In order to determine the effectiveness of gamma knife (GK) radiosurgery in patients with malignant melanoma metastases, the authors conducted a prospective multicenter study. Forty-five patients with a total of 96 lesions were treated and followed to measure survival time, tumor control rate, and Karnofsky Performance Scale (KPS) score. The mean survival time was 8.7 months (median 4.2 months), and tumor control was achieved in 86% of lesions. When obtained, the median preoperative KPS of 80 was maintained at a median of 80 post-GK treatment. The authors found GK treatment for metastases of malignant melanoma to be highly effective in controlling tumor growth. Survival rates obtained after GK treatment were found to be superior to historically obtained data concerning external beam radiotherapy follow up. Radiosurgery with the GK can therefore be considered a good primary treatment option for metastatic brain disease of malignant melanoma.

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This paper presents a compression scheme for digital still images, by using the Kohonen's neural network algorithm, not only for its vector quantization feature, but also for its topological property. This property allows an increase of about 80% for the compression rate. Compared to the JPEG standard, this compression scheme shows better performances (in terms of PSNR) for compression rates higher than 30.

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The aim of our study was to asses the effects of feeding emissions of a plant producing metals from heavy metal-containing ore upon the humoral immunity in sheep. Three-year-old sheep of the Wallachian breed were included in an experiment and they were divided into two groups. The experimental group (5 animals) was administered emission-containing (prevailingly Cu and Zn) capsules for 3 weeks at a dose amounting to the twofold and during week four the threefold of the daily intake of sheep bred in the exposed area. The animals were subcutaneously immunized with ovalbumin (OVA, SIGMA A 5503) in 10% alhydrogel at a dose of 2 mg/100 kg l.w. In weekly intervals, blood samples were analyzed for specific antibody and total immunoglobulin levels. In both groups, OVA antibody formation was most pronounced in the 3rd and 5th weeks of observation. It was significantly (P < 0.01) higher in the experimental animals than in the controls (1.021, 0.641 and 1.138 vs. 0.435, 0.265 and 0.673 in the 3rd, 4th and 5th weeks, respectively). In the experimental group, total immunoglobulin concentrations slightly increased from 33.5 U ZST (starting value) to 38.72 U ZST (final value). As to the total immunoglobulin levels, no significant differences were determined between the two groups. It can be seen from the results that short-term administration of emissions promotes increased specific OVA antibody formation and a slight increase in total immunoglobulin levels. At the same time the ELISA method was proved to be suitable for specific antibody detection as a part of humoral immunity assessment.

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During the period of one year, from the 21. 4. 1992 to 21. 4. 1993, a total of 201 radiosurgical sessions on 181 patients were performed with the first Austrian Gamma-unit in Graz. 42% of radiosurgical sessions were undertaken for malignomas, 20% for meningiomas, 11.5% for vascular malformations, 9% for neurinomas, 8.5% for low grade astrocytomas and glomus jugulare tumours, 5% for sellar and suprasellar lesions, and 4% for functional disorders. Dose plan data for all the lesions treated are shown. Clinical and imaging data of the first year which are available for 120 patients (66%) are presented and discussed.

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Kohonen maps are self-organizing neural networks that classify and quantify n-dimensional data into a one- or two-dimensional array of neurons. Most applications of Kohonen maps use simulations on conventional computers, eventually coupled to hardware accelerators or dedicated neural computers. The small number of different operations involved in the combined learning and classification process, however, makes the Kohonen model particularly suited to a dedicated VLSI implementation, taking full advantage of the parallelism and speed that can be obtained on the chip. A fully analog implementation of a one-dimensional Kohonen map, with on-chip learning and refreshment of on-chip analog synaptic weights, is proposed. The small number of transistors in each cell allows a high degree of parallelism in the operations, which greatly improves the computation speed compared to other implementations. The storage of analog synaptic weights, based on the principle of current copiers, is emphasized. It is shown that this technique can be used successfully for the realization of VLSI Kohonen maps.