The Yellow River flow has decreased substantially in recent decades, and the river often dried up in the lower reach and failed to reach the sea. Climate change and human disruption have been suggested as major causes of the flow reduction, but quantification of their relative contribution is challenging due to limited instrumental records and disturbance by dams. Here we use a basin‐wide tree ring network to reconstruct the Yellow River flow for the past 1,200 years and show that the flow exhibits marked amplitude variations that are closely coupled to the hydrological mean state swings at multidecadal to centennial timescales. Recent flow should have increased to the highest level of the past 1,200 years if there were no human disruption. However, human activities have caused a loss of nearly half of natural flow since the late 1960s and are the main culprit for recent downstream flow reduction.

BackgroundPosterior instrumentation after deformity correction is an important method for reconstruction of spinal stability in the management of lumbar tuberculosis (TB). However, the commonly used methods include both long- and short-segment fixation of normal motor units. There has been no report regarding affected-vertebrae fixation of lumbar TB.MethodsData from 135 patients with lumbar TB who underwent posterior instrumentation and either affected-vertebrae fixation or short-segment fixation using a combined posterior and anterior approach were retrospectively reviewed. Among these patients, 71 cases were treated with affected-vertebrae fixation, and 64 cases were treated with short-segment fixation. Debridement, bone grafting, deformity correction, and decompression were performed within all affected segments. Operative times, intra-operative blood loss, TB cure rates, bone graft fusion rates, degree of deformity correction, neurological function, pain recovery, and complications were analyzed.ResultsComparing affected-vertebrae fixation vs. short-segment fixation groups, respectively, the number of the affected segments was 107 vs. 98; average number of affected segments was 1.51 vs. 1.53; total number of fixed segments was 107 vs. 226; average number of fixed segments was 1.51 vs. 3.53; average blood loss was 726.2 ml vs. 948.5 ml; average operative time was 210.4 min vs. 270.3 min; and average hospitalization costs were 29,000 RMB vs. 42,000 RMB (all p values < 0.05). In the affected-vertebrae fixation vs. short-segment fixation groups, respectively, TB cure rates were 82.61% vs. 84.62% at 6 months after operation and 97.83% vs. 97.44% at 5 years after operation; bone fusion rates were 86.96% vs. 87.18% at 6 months after operation and 97.83% vs. 97.66% at 5 years after operation; average number of degrees of Cobb’s angle correction were 13.1° vs. 13.7°; average correction losses were 1.9° vs. 1.4°; and complication rates were 12.04% vs. 12.97% (all p values > 0.05).ConclusionUnder strict surgical indications, posterior instrumentation on affected-vertebrae is a safe, effective, and feasible fixation method in the treatment of lumber TB.

February-April drought strongly affects agriculture and socio-economics in southeastern China, yet its long-term variability has not been assessed due to the shortness of instrumental records. In this study, we reported a 168-year tree-ring width chronology from a steep, low-elevation site with thin soil layers in the Xianxia Mountains, southeastern China. Contrary to the existing chronologies that are mostly temperature sensitive, this chronology contained a strong February-April precipitation signal, indicating great potential for tree-ring based precipitation reconstructions in southeastern China. The reconstruction explained 47.8% of the instrumental variance during 1951-2012. The full reconstruction indicated that there were 3 dry periods

Long-term, high-resolution proxy records containing cold season temperature signals are scarce on the southeastern Tibetan Plateau (TP), limiting our understanding of regional climate and the potential driving forces. In this study, we present a nearly three centuries long reconstruction of winter (December-February) mean temperature for the central Hengduan Mountains, southeastern TP. The reconstruction is derived from a composite tree-ring width chronology of Pinus yunnanensis Franch from two high elevation sites (> 3000 meters above sea level). Our reconstruction passes all standard calibration-verification schemes and explains nearly 73% of the variance of the original instrumental data. However, we were constrained to calibrate our full period (1718-2013) reconstruction of December-February mean temperature on the calibration period from 1959-1992 only, due to a decrease in temperature sensitivity of tree-ring index exhibited after 1992. Spatial correlation analysis shows that our reconstruction represents large-scale temperature variations in southwest China and the eastern TP. Our reconstructed December-February mean temperature shows a close association with the Atlantic Multidecadal Oscillation (AMO) over the past three centuries, with warm (cold) periods coinciding with the positive (negative) phases of the AMO. This persistent relationship suggests that the AMO may have been a key driver of multidecadal winter temperature variations on the southeastern TP.

Objective: The present study investigated the clinical significance of mannose-binding lectin 2 (MBL2), cluster of differentiation 14 (CD14) and tumour necrosis factor-α (TNF-α) gene polymorphisms in patients with spinal tuberculosis (TB) in Chinese population. Methods: A total of 240 patients with spinal TB were enrolled in the present study from May 2013 to August 2016 at Hangzhou Red Cross Hospital. A total of 150 age- and sex-matched healthy subjects were enrolled as controls. The genomic DNA was extracted from the peripheral blood of all subjects, and the MBL2, CD14 and TNF-α gene polymorphisms were detected by direct DNA sequencing. Results: (1) Compared with controls, patients with spinal TB exhibited a significantly higher frequency of the XY genotype at the −221G>C polymorphism as well as the Q allele and PQ genotype or an association with the QQ genotype at the +4C>T polymorphism in the MBL2 gene. (2) Compared with controls, patients with spinal TB exhibited a significantly higher frequency of the T allele and TT genotype or an association with the CT genotype at the −159C>T polymorphism in the CD14 gene. (3) Compared with controls, patients with spinal TB exhibited a significantly higher frequency of the T allele and the CT genotype or an association with the TT genotype at the TNF-857 polymorphism in the TNF-α gene. Conclusion: The −221G>C polymorphism of MBL2, the −159C>T polymorphism of CD14 and the TNF-857 polymorphism of TNF-α are risk factors for spinal TB and may be involved in the development of spinal TB in the Chinese population. These factors are indicators of susceptibility to spinal TB and require clinical attention.