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Fine-grained sediment (grain size under 2,000 µm) builds floodplains and deltas, and shapes the coastlines where much of humanity lives. However, a universal, physically based predictor of sediment flux for fine-grained rivers remains to be developed. Herein, a comprehensive sediment load database for fine-grained channels, ranging from small experimental flumes to megarivers, is used to find a predictive algorithm. Two distinct transport regimes emerge, separated by a discontinuous transition for median bed grain size within the very fine sand range (81 to 154 µm), whereby sediment flux decreases by up to 100-fold for coarser sand-bedded rivers compared to river with silt and very fine sand beds. Evidence suggests that the discontinuous change in sediment load originates from a transition of transport mode betweenmixed suspended bed load transport and suspensiondominated transport. Events that alter bed sediment size near the transition may significantly affect fluviocoastal morphology by drastically changing sediment flux, as shown by data from the Yellow River, China, which, over time, transitioned back and forth 3 times between states of high and low transport efficiency in response to anthropic activities. [ABSTRACT FROM AUTHOR]

The non-harmonious combination of insufficient water and excessive sediment causes many problems for the Yellow River. These problems include severe sedimentation in the Sanmenxia reservoir, the rising of the water level at Tongguan for a given discharge (1000 m³/s) and the rising of the bed level of the Lower Yellow River (LYR). How to lower the Tongguan Water Level (TGWL) and alleviate sedimentation in the LYR has become one of the most important issues in managing the Yellow River. This paper provides a summary of recent studies by authors on solving these key sediment problems in the Yellow River. [ABSTRACT FROM AUTHOR]

Previous research on runoff show flow and sediment movement in rivers, and river bed variations are usually separated. This paper from the point of view of the basin as a whole system, presents an integrated approach by combining runoff simulation with numerical model of sediment transport in rivers to simulate the whole processes of hydrological variables and flow-caused bed variations from the very upper part of the basin to the river mouth. To accomplish this purpose, BTOPMC, a rainfall-runoff model, and NUSTM-1D, a well-developed numerical model for sediment transport and river bed variations, are selected to form a combined model. The application of the proposed model to the lower Yellow River shows that it can properly simulate rainfall-caused runoff the change of suspended sediment concentration along the river, and river bed variation. [ABSTRACT FROM AUTHOR]

Purpose: Cetuximab in combination with chemotherapy is a standard-of-care first-line treatment regimen for patients with RAS wild-type (wt) metastatic colorectal cancer (mCRC); however, the efficacy of cetuximab plus leucovorin, fluorouracil, and oxaliplatin (FOLFOX) has never before been proven in a controlled and randomized phase III trial. To our knowledge, the TAILOR trial ( ClinicalTrials.gov identifier: NCT01228734) is the first randomized, multicenter, phase III study of the addition of cetuximab to first-line FOLFOX prospectively choosing a RAS wt population and thus providing confirmative data for the efficacy and safety of cetuximab plus FOLFOX versus FOLFOX alone., Patients and Methods: TAILOR is an open-label, randomized (1:1), multicenter, phase III trial in patients from China comparing FOLFOX-4 with or without cetuximab in RAS wt ( KRAS / NRAS , exons 2 to 4) mCRC. The primary end point of TAILOR was progression-free survival time; secondary end points included overall survival time, overall response rate, and safety and tolerability., Results: In the modified intent-to-treat population of 393 patients with RAS wt mCRC, adding cetuximab to FOLFOX-4 significantly improved the primary end point of progression-free survival time compared with FOLFOX-4 alone (hazard ratio, 0.69; 95% CI, 0.54 to 0.89; P = .004; median, 9.2 v 7.4 months, respectively), as well as the secondary end points of overall survival time (current assessment after 300 events: hazard ratio, 0.76; 95% CI, 0.61 to 0.96; P = .02; median, 20.7 v 17.8 months, respectively) and overall response rate (odds ratio, 2.41; 95% CI, 1.61 to 3.61; P < .001; 61.1% v 39.5%, respectively). Treatment was well tolerated, and there were no new or unexpected safety findings., Conclusion: The TAILOR study met all of its objectives and relevant clinical end points, confirming cetuximab in combination with FOLFOX as an effective standard-of-care first-line treatment regimen for patients with RAS wt mCRC.

Purpose: The phase III BEYOND trial was undertaken to confirm in a Chinese patient population the efficacy seen with first-line bevacizumab plus platinum doublet chemotherapy in globally conducted studies., Patients and Methods: Patients age ≥ 18 years with locally advanced, metastatic, or recurrent advanced nonsquamous non-small-cell lung cancer (NSCLC) were randomly assigned to receive carboplatin (area under the curve, 6) intravenously and paclitaxel (175 mg/m(2)) intravenously (CP) on day 1 of each 3-week cycle, for ≤ six cycles, plus placebo (Pl+CP) or bevacizumab (B+CP) 15 mg/kg intravenously, on day 1 of each cycle, until progression, unacceptable toxicity, or death. The primary end point was progression-free survival (PFS); secondary end points were objective response rate, overall survival, exploratory biomarkers, safety., Results: A total of 276 patients were randomly assigned, 138 to each arm. PFS was prolonged with B+CP versus Pl+CP (median, 9.2 v 6.5 months, respectively; hazard ratio [HR], 0.40; 95% CI, 0.29 to 0.54; P < .001). Objective response rate was improved with B+CP compared with Pl+CP (54% v 26%, respectively). Overall survival was also prolonged with B+CP compared with Pl+CP (median, 24.3 v 17.7 months, respectively; HR, 0.68; 95% CI, 0.50 to 0.93; P = .0154). Median PFS was 12.4 months with B+CP and 7.9 months with Pl+CP (HR, 0.27; 95% CI, 0.12 to 0.63) in EGFR mutation-positive tumors and 8.3 and 5.6 months, respectively (HR, 0.33; 95% CI, 0.21 to 0.53), in wild-type tumors. Safety was similar to previous studies of B+CP in NSCLC; no new safety signals were observed., Conclusion: The addition to bevacizumab to carboplatin/paclitaxel was well tolerated and resulted in a clinically meaningful treatment benefit in Chinese patients with advanced nonsquamous NSCLC., (© 2015 by American Society of Clinical Oncology.)