Fishing experiments with frame nets in Hirakud reservoir, Orissa

Experiments conducted with frame nets of sizes 1.0 m, 1.25 m 1.5 m, 1.75 m and 2.0 m in Hirakud reservoir showed that the net with 1.75 m frame gave the highest catches

Comparative efficiency of frame nets and trammel nets

Fishing experiments were conducted simultaneously with frame nets and trammel nets in the Hirakud Reservoir and the results indicated the relative superiority of frame nets, whose catch rate was two times more than that of the trammel nets

Effect of hanging coefficient on the efficiency of frame net

Comparative fishing experiments with frame nets of 0.4 and 0.5 hanging coefficients were conducted. Results indicate that net with hanging coefficient of 0.4 as more effective for better catch

Coloured gill nets for reservoir fishing

Experimental fishing with different coloured nets has shown that white net yields better catch. The efficiency of the coloured nets was in the order yellow, grey, green and blue. Though there is little evidence to show some species preference to a particular colour, the results were not conclusive as the analysis of variance indicated that interaction between species and colour is significant only at 5% level

Effect of variation in mesh size on trawl efficiency

Result of comparative fishing trials with a bulged belly design with three different mesh ranges in the body and wing to study the effect of mesh size difference on the performance of gear is discussed. While there is no significant difference in catch rate, predictably the 40 mm mesh size trawl fared wen when small sized fish like anchovies formed the major catch. The trawls with 60 and 80 mm mesh size gave better horizontal spread at a lower resistance showing savings in fuel

The evolution of non-small cell lung cancer metastases in TRACERx

Metastatic disease is responsible for the majority of cancer-related deaths. We report the longitudinal evolutionary analysis of 126 non-small cell lung cancer (NSCLC) tumours from 421 prospectively recruited patients in TRACERx who developed metastatic disease, compared with a control cohort of 144 non-metastatic tumours. In 25% of cases, metastases diverged early, before the last clonal sweep in the primary tumour, and early divergence was enriched for patients who were smokers at the time of initial diagnosis. Simulations suggested that early metastatic divergence more frequently occurred at smaller tumour diameters (less than 8 mm). Single-region primary tumour sampling resulted in 83% of late divergence cases being misclassified as early, highlighting the importance of extensive primary tumour sampling. Polyclonal dissemination, which was associated with extrathoracic disease recurrence, was found in 32% of cases. Primary lymph node disease contributed to metastatic relapse in less than 20% of cases, representing a hallmark of metastatic potential rather than a route to subsequent recurrences/disease progression. Metastasis-seeding subclones exhibited subclonal expansions within primary tumours, probably reflecting positive selection. Our findings highlight the importance of selection in metastatic clone evolution within untreated primary tumours, the distinction between monoclonal versus polyclonal seeding in dictating site of recurrence, the limitations of current radiological screening approaches for early diverging tumours and the need to develop strategies to target metastasis-seeding subclones before relapse

The evolution of lung cancer and impact of subclonal selection in TRACERx

Lung cancer is the leading cause of cancer-associated mortality worldwide. Here we analysed 1,644 tumour regions sampled at surgery or during follow-up from the first 421 patients with non-small cell lung cancer prospectively enrolled into the TRACERx study. This project aims to decipher lung cancer evolution and address the primary study endpoint: determining the relationship between intratumour heterogeneity and clinical outcome. In lung adenocarcinoma, mutations in 22 out of 40 common cancer genes were under significant subclonal selection, including classical tumour initiators such as TP53 and KRAS. We defined evolutionary dependencies between drivers, mutational processes and whole genome doubling (WGD) events. Despite patients having a history of smoking, 8% of lung adenocarcinomas lacked evidence of tobacco-induced mutagenesis. These tumours also had similar detection rates for EGFR mutations and for RET, ROS1, ALK and MET oncogenic isoforms compared with tumours in never-smokers, which suggests that they have a similar aetiology and pathogenesis. Large subclonal expansions were associated with positive subclonal selection. Patients with tumours harbouring recent subclonal expansions, on the terminus of a phylogenetic branch, had significantly shorter disease-free survival. Subclonal WGD was detected in 19% of tumours, and 10% of tumours harboured multiple subclonal WGDs in parallel. Subclonal, but not truncal, WGD was associated with shorter disease-free survival. Copy number heterogeneity was associated with extrathoracic relapse within 1 year after surgery. These data demonstrate the importance of clonal expansion, WGD and copy number instability in determining the timing and patterns of relapse in non-small cell lung cancer and provide a comprehensive clinical cancer evolutionary data resource