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Abstract Background The use of combustible vegetable waste in the manufacture of refractory insulating firebricks has a double advantage: making use of vegetable waste and decreasing the production cost of bricks. Results Ground date seeds were added to kaolin and grog at different ratios and their blend was mixed with water. The wet mixtures were shaped in steel molds, dried overnight at 90 °C and fired at 1200 °C for 2 h. The physical and mechanical properties of the fired bricks were determined and found to be incompatible with standard values. Small amounts of polystyrene beads and perlite were then added to decrease the bulk density and increase the crushing strength. A mixture composed of 6% date seed, 72.5% kaolin, 17.5% grog, 2.5% perlite and 1.5% polystyrene produced bricks that abided by Indian Standards 2042 requirements regarding their bulk density, porosity, crushing strength, percent linear change on reheat and thermal conductivity at 600 °C. Conclusions Date seeds have been successfully used as pore generating material in the preparation of Class B insulating firebricks, in a mixture with kaolin, grog and small amounts of polystyrene and perlite.

In the Ptch+/- mouse model for embryonal rhabdomyosarcoma (ERMS), we recently showed that oncogenic (onc) H-, K- or NRAS mutations do not influence tumor growth when induced at the advanced, full-blown tumor stage. However, when induced at the invisible ERMS precursor stage at 4 weeks of age, tumor development was enforced upon oncHRAS and oncKRAS but not by oncNRAS, which instead initiated tumor differentiation. These data indicate that oncRAS-associated processes differ from each other in dependency on the isoform and their occurrence during tumor development. Here, we investigated the outcome of oncNRAS induction at an earlier ERMS precursor stage at 2 weeks of age. In this setting, oncNRAS accelerates tumor growth because it significantly shortens the ERMS-free survival and increases the ERMS incidence. However, it does not seem to alter the differentiation of the tumors. It is also not involved in tumor initiation. Together, these data show that oncNRAS mutations can accelerate tumor growth when targeting immature ERMS precursors within a specific time window, in which the precursors are permissive to the mutation and show that oncNRAS-associated processes differ from each other in dependency on their occurrence during tumor development.

The development of skeletal muscle from immature precursors is partially driven by canonical WNT/β-catenin signaling. Rhabdomyosarcomas (RMS) are immature skeletal muscle-like, highly lethal cancers with a variably pronounced blockade of muscle differentiation. To investigate whether canonical β-catenin signaling in RMS is involved in differentiation and aggressiveness of RMS, we analyzed the effects of WNT3A and of a siRNA-mediated or pharmacologically induced β-catenin knock-down on proliferation, apoptosis and differentiation of embryonal and alveolar RMS cell lines. While the canonical WNT pathway was maintained in all cell lines as shown by WNT3A induced AXIN expression, more distal steps including transcriptional activation of its key target genes were consistently impaired. In addition, activation or inhibition of canonical WNT/β-catenin only moderately affected proliferation, apoptosis or myodifferentiation of the RMS tumor cells and a conditional knockout of β-catenin in RMS of Ptchdel/+ mice did not alter RMS incidence or multiplicity. Together our data indicates a subordinary role of the canonical WNT/β-catenin signaling for RMS proliferation, apoptosis or differentiation and thus aggressiveness of this malignant childhood tumor.