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21.
The assessment of the harmfulness of moulding and core sands is mainly based on investigations of compositions of gases emitted by liquid casting alloys during the mould pouring. The results of investigations of moulding sands obtained under industrial conditions are presented in this paper. A unique research stand was designed and built for this aim. It allowed us to determine emissions of gases at individual stages of casting a mass up to 50 kg. This approach enables simulation of foundry conditions. Moulding sands bound by organic binders (phenol-formaldehyde; furan), inorganic binders and green sand, were subjected to investigations. The composition of gases that evolved during the individual stages, pouring, cooling and knocking out, was tested each time, and the contents of Polycyclic Aromatic Hydrocarbons (PAHs) and benzene, toluene, ethylbenzene, and xylenes (BETX) were analysed. Investigations indicated that the emission of gases from sands with inorganic binders is negligible when compared with the emission of gases from sands with organic binders. The emission of gases from green sand is placed in the middle of the scale. As an example: the sand with furan resin emitted 84 mg of BTEX (in recalculation for 1 kg of sand) while from sands with inorganic binders there was a maximum of 2.2 mg (for 1 kg of sand). In the case of sands with inorganic binders, MI and MC sands indicated comparable and very low emissions of gases from the PAHs group, at the level of 0.018 mg and 0.019 mg for 1 kg of sand, respectively. The higher emission of PAHs from MG sand is the result of its different way of hardening (a binder was of an organic character) than of sands MI and MC.  相似文献   
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Splenectomy is considered standard surgical therapy in hereditary spherocytosis. The procedure is indicated in patients with severe anemia, recurrent hemolytic, and aplastic crises. The aim of the study was to assess treatment outcomes in patients with hereditary spherocytosis who underwent total or partial laparoscopic splenectomy. Fifteen patients aged 4–17 yr underwent laparoscopic splenectomy from 2009 to 2012. Partial and total splenectomies were performed (five and 10 children, respectively). Hematologic parameters, liver function tests, and splenic volume before and after the surgery were analyzed retrospectively. Total follow‐up was 1–30 months. Hospitalization and operating time were similar in both groups. In partial splenectomy group, branches of splenic arteries gave better blood supply than short gastric vessels. In both groups, hematologic parameters were improved. Postoperative markedly elevated platelet count was maintained up to 6 months, and after that, platelet count gradually decreased to normal values. Bilirubin level was decreased in early postoperative period; however, it increased later to achieve levels lower than in preoperative period. No severe general infections were observed in both groups. Laboratory parameters (hemoglobin and bilirubin concentrations and RBC) after the surgery improved in all patients, and the effect was maintained during 12 months of follow‐up. Platelet count increased significantly after the surgery and was maintained at high levels during the next 6 months. However, it returned to preoperative levels within a year after the surgery. Our study showed that partial splenectomy was not inferior to total splenectomy. However, full assessment requires longer follow‐up and larger group of patients.  相似文献   
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Nervous system disorders are among the most severe disorders. Significant breakthroughs in contemporary clinical practice may provide brain-computer interfaces (BCIs) and neuroprostheses (NPs). The aim of this article is to investigate the extent to which the ethical considerations in the clinical application of brain-computer interfaces and associated threats are being identified. Ethical considerations and implications may significantly influence further development of BCIs and NPs. Moreover, there is significant public interest in supervising this development. Awareness of BCIs’ and NPs’ threats and limitations allow for wise planning and management in further clinical practice, especially in the area of long-term neurorehabilitation and care.  相似文献   
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Correction for ‘A novel biomass-based support (Starbon) for TiO2 hybrid photocatalysts: a versatile green tool for water purification’ by Juan Carlos Colmenares et al., RSC Adv., 2013, 3, 20186–20192.

The authors regret that the Experimental section (2.2 Preparation of hybrid TiO2-based carbonaceous materials) of the original article requires a small correction. There was apparently some minor arithmetic error involved in the calculation of the nominal mass percentage of TiO2 which was deposited on carbonaceous carbon materials. The nominal mass percentage of TiO2 deposited on carbonaceous carbon materials was calculated incorrectly (should be 20.9 wt% TiO2 instead of 25 wt% TiO2). It should be recognized that this error does not affect any discussion and conclusions reported in this publication. However, this correction is necessary to determine the nominal mass percentage of TiO2 which was deposited on carbon materials and improve the quality of this scientific publication.The Royal Society of Chemistry apologises for these errors and any consequent inconvenience to authors and readers.  相似文献   
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