RESUMO
Carbon export efficiency is a key indicator of the capacity of biological pump, but the controlling mechanism of the efficiency remains unclear. Our findings revealed that interannual variations in seasonal carbon export efficiency are determined by direct factors including riverine nutrient fluxes, stratification, residence time. These direct factors are finally attributed to two indirect factors (human activities and climate change). We quantified the absolute contributions of direct and indirect factors to carbon export efficiency. The results showed that the carbon export efficiency in the northern Gulf of Mexico in spring (summer; autumn; winter) was driven by human activities, which accounted for an absolute contribution of 16.02% (7.20%; 4.00%; 8.49%, respectively) through riverine nutrient fluxes, and by climate change, which accounted for an absolute contribution of 33.51% (21.43%; 25.73%; 15.80%, respectively) through stratification and water residence time. Moreover, carbon export efficiency could be predicted by MEI of 8 months earlier.
Assuntos
Carbono , Mudança Climática , Estações do Ano , Golfo do México , Carbono/metabolismo , Monitoramento Ambiental , Ciclo do Carbono , Água do Mar/químicaRESUMO
INTRODUCTION AND OBJECTIVES: The occurrence of hepatocellular carcinoma (HCC) is not entirely clear at present. This study comprehensively described the landscape of genetic aberrations in Chinese HCC patients using next-generation sequencing (NGS) and investigated the association of genetic aberrations with clinicopathological characteristics and prognosis. MATERIALS AND METHODS: The clinicopathological data of 78 HCC patients undergoing surgery were retrospectively analyzed. The genomic DNA extracted from tumor samples was detected using a NGS-based gene panel. RESULTS: Mutations in TP53 (55%), TERT (37%), MUC16 (29%) and CTNNB1 (27%) were most common in HCC. The co-occurrences between frequently mutated genes occurring ≥10% were relatively common in HCC. Forty-eight (61.5%) cases harbored DNA damage repair gene mutations, mainly including PRKDC (11.5%), SLX4 (9.0%), ATM (7.7%), MSH6 (7.7%), and PTEN (6.4%), and 39 (50.0%) patients had at least one actionable mutation. FH amplification (odds ratio: 3.752, 95% confidence interval: 1.170-12.028, p=0.026) and RB1 mutations (odds ratio: 13.185, 95% confidence interval: 1.214-143.198, p=0.034) were identified as the independent risk factors for early postoperative recurrence in HCC. CONCLUSIONS: Our study provides a novel insight into the genomic profiling of Chinese HCC patients. FH amplification and RB1 mutations may be associated with an increased risk of early postoperative recurrence in HCC.