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Background: About 50% of non-small cell lung cancer (NSCLC) patients develop distant metastases following pulmonary resection. Currently, there are no reliable factors allowing for individual selection of high-risk patients for adjuvant systemic therapies.Methods: We assessed by quantitative reverse transcription PCR microRNA (miRNA) expression in 273 stage I-IIIA NSCLC samples. Expression of 677 miRNAs was evaluated in fresh-frozen tumour samples in the training cohort of 50 squamous cell carcinoma (SCC) patients who underwent curative surgery. Of those, 20 patients developed distant metastases, and 30 were free of recurrence for >4 years. In the second step, miRNAs with highest predictive value for distant relapse were re-evaluated in formalin-fixed paraffin-embedded material in an independent group of 134 stage I-IIIA SCC patients. Additionally, the same miRNAs were investigated in 89 lung adenocarcinoma (AC) patients and in normal lung parenchyma (NLP).Results: In the training cohort of SCC, six miRNAs were differently expressed in the non-recurrent vs recurrent groups and correlated with distant recurrence-free survival, however none reached the level of significance after correction for multiple testing. Of these six miRNAs, miR-662, -192 and -192* were confirmed as prognostic in the independent SCC cohort. Expression of miR-128, -10b, -502-3p and -192 differed between SCC and AC, and miR-128 and -192 - between NLP and NSCLC.Conclusions: We identified three new miRNAs predictive of distant relapse in operable SCC. Future miRNA studies should account for differences between NSCLC subtypes. [ABSTRACT FROM AUTHOR]

Thermal silver plating method by means of nanosilver-based paint could be an alternative to electrochemical processes. Electrochemical silver layering on aluminium is typically achieved with an intermediate layer, which provides very good adhesion of the layer to the aluminium surface but increases the resistance of the whole junction system. In the method of silver plating promoted by the authors, the intermediate layer is eliminated. The layer of silver paint was applied directly on the aluminium surface by spraying using aerograph. Procured silver layers, according to ISO 2409, prove proper adhesion to aluminium. The value of contact resistance with a pressure of 300 N cm−2 and current load of 200 A is 0.03 μΩ mm−2, which is comparable to the contact resistance of layers generated by electrochemical means. This new method decreases the level of toxic waste emission and therefore is less harmful for the natural environment. It is also cheaper and simpler than the electrochemical process. An additional advantage is the possibility of silver plating of the chosen surfaces with various shapes.

The Low Temperature Joining Technique (LTJT) using silver compounds enables to significantly increase the thermal conductivity between joined elements, which is much higher than for soldered joints. However, it also makes difficult to measure the thermal conductivity of the joint. The Laser Flash Analysis (LFA) is a non-intrusive method of measuring the temperature rise of one surface of a specimen after excitation with a laser pulse of its other surface. The main limitation of the LFA method is its standard computer software, which assumes the dimensions of a bonded component to be similar to those of the substrate, because it uses the standard Parker’s formula dedicated for one-dimensional heat flow. In the paper a special design of measured specimen was proposed, consisting of two copper plates of different size joined with the sintered silver layer. It was shown that heat properties of these specimens can also be measured after modifying the LFA method. The authors adapted these specimens by masking the false heat signal sourced from the uncovered plate area. Another adaptation was introducing a correcting factor of the heat travel distance, which was calculated with heat-flow simulations and placed into the Parker’s formula. The heat-flow simulated data were compared with the real LFA measurement results, which enabled estimation of the joint properties, e.g. its porosity.