A global dataset of the fraction of absorbed photosynthetically active radiation for 1982-2022.

The fraction of absorbed photosynthetically active radiation (FPAR) is an essential biophysical parameter that characterizes the structure and function of terrestrial ecosystems. Despite the extensive utilization of several satellite-derived FPAR products, notable temporal inconsistencies within each product have been underscored. Here, the new generation of the GIMMS FPAR product, GIMMS FPAR4g, was developed using a combination of a machine learning algorithm and a pixel-wise multi-sensor records integration approach. PKU GIMMS NDVI, which eliminates the orbital drift and sensor degradation issues, was used as the data source. Comparisons with ground-based measurements indicate root mean square errors ranging from 0.10 to 0.14 with R-squared ranging from 0.73 to 0.87. More importantly, our product demonstrates remarkable spatiotemporal coherence and continuity, revealing a persistent terrestrial darkening over the past four decades (0.0004 yr-1, p < 0.001). The GIMMS FPAR4g, available for half-month intervals at a spatial resolution of 1/12° from 1982 to 2022, promises to be a valuable asset for in-depth analyses of vegetation structures and functions spanning the last 40 years.

Comment on "Recent global decline of CO2 fertilization effects on vegetation photosynthesis".

Wang et al. (Research Articles, 11 December 2020, p. 1295) reported a large decrease in CO2 fertilization effect (CFE) across the globe during the period 1982­2015 and suggested that ecosystem models underestimate the rate of CFE decline. We find that their claims are artifacts of incorrect processing of satellite data and problematic methods for deriving and comparing CFE between satellite data and model simulations.

Delayed total hip arthroplasty after failed treatment of acetabular fractures: an 8- to 17-year follow-up study.

BACKGROUND: Delayed total hip arthroplasty (THA) is a reliable procedure following failed treatment of acetabular fractures. The aim of the present study was to evaluate the influence of the type of fracture treatment and modern ceramic bearing on the clinical outcomes of delayed THA. METHODS: Between January 1997 and January 2008, 33 patients (33 hips) underwent cementless THA after failed acetabular fractures. Twenty-one were initially treated by open reduction internal fixation (ORIF) and 12 had non-ORIF. Joint articulation was either conventional metal-on-polyethylene (MOP) or ceramic-on-ceramic (COC). Intraoperative measures and preoperative and follow-up clinical, radiological, and functional outcomes were compared between the ORIF and non-ORIF groups. RESULTS: Surgery duration, blood loss, and transfusion requirement were greater in the ORIF group than in the non-ORIF group (p < 0.05). Significant improvement in Harris Hip Scores was seen post-surgery in both groups. However, a significant difference in the mean Harris Hip Score was not observed between the two groups (p = 0.57). Six patients in the ORIF group required acetabular reconstructive procedures to address bony defects compared to seven patients in the non-ORIF group (p = 0.09). The rate of anatomical restoration was 58.3% (7/12) in the non-ORIF group and 42.9% (9/21) in the ORIF group (p = 0.12). Radiolucent lines were observed in the MOP group and none in the COC group. Overall survival rate was similar in both groups (p = 0.85): 89.3% in the ORIF group and 87.5% in the non-ORIF group. CONCLUSION: Delayed THA with previous acetabular fractures is a challenging procedure. Initial fracture treatment does not influence the outcome of delayed THA, and modern ceramic bearing has promising results in the long-term follow-up.

[Mid-term effectiveness of large-head metal-on-metal total hip arthroplasty].

Objective: To explore the mid-term effectiveness of large-head metal-on-metal total hip arthroplasty (THA). Methods: A retrospective analysis was made on the clinical date of 40 patients (43 hips) who were treated with the large-head metal-on-metal THA between April 2009 and June 2010. There were 18 males (20 hips) and 22 females (23 hips) with an average age of 55.1 years (range, 20-85 years). Unilateral hip was involved in 37 cases and bilateral hips in 3 cases. The disease causes included osteonecrosis of the femoral head in 14 cases (15 hips), osteoarthritis in 6 cases (7 hips), rheumatoid arthritis in 4 cases (4 hips), femoral neck fracture in 4 cases (4 hips), and developmental dysplasia of the hip in 12 cases (13 hips). Before operation, the Harris score and University of California Los Angeles (UCLA) score were 38.51±5.62 and 4.21±1.43, respectively. The visual analogue scale (VAS) score was 6.78±0.95. Results: All patients were followed up 6.7-8.3 years (mean 7.5 years). All incisions healed primarily and no neurovascular injury, infection, and hip dislocation occurred. At last follow-up, the Harris score and UCLA score were 93.33±3.21 and 7.32±1.45, respectively, showing significant differences when compared with preoperative scores ( t=51.753, P=0.000; t=23.232, P=0.000). The thigh pain occurred in 3 cases (3 hips) in whom the inflammatory pseudotumor of soft tissues was found in 1 case (1 hip). Postoperative X-ray films showed that the acetabular abduction angle and anteversion angle were (46.5±3.2)° and (14.8±3.6) °, respectively. The initial stability of femoral stem prosthesis was excellent in 39 hips and good in 4 hips according to Mulliken standard. Osteolysis occurred in 2 hips and revision was performed in 1 hip of secondary loosening of prosthesis. The rest patients had no prosthesis loosening or sinking. Conclusion: The mid-term effectiveness of large-head mental-on-mental THA in treatment of the terminal diseases of hips are good.