Hydrometeorological models are often evaluated and optimized on the basis of micrometeorological measurements. However, it has been known for more than three decades that surface measurements of sensible and latent he...Hydrometeorological models are often evaluated and optimized on the basis of micrometeorological measurements. However, it has been known for more than three decades that surface measurements of sensible and latent heat energy (LE) are systematically underestimated. We studied this problem using six years of eddy-correlation measurements for four fields (corn, soybean, and prairie) in central Iowa, USA. We recorded major components of the energy equation (i.e. net radiation, sensible heat flux, LE, and soil heat flux, photosynthesis), and indirectly estimated most of the minor components of energy balance (namely storage in the soil, canopy and air). Storage in the canopy was related to leaf area index (LAI) acquired from Moderate Resolution Imaging Spectrometer (MODIS). In this paper, a diagnostic approach is investigated where systematic error is identified first. Three dimensional (3D) plots of the residual of energy equation vs. potential variables indicated the imbalance was largest mainly during the cold non-growing season when the soil was dry. Correlations between energy balance residual (EBR) and energy components showed that soil storage was not precisely estimated. Finally, an a-posteriori analysis (constrained linear multiple regression (CMLR)) was conducted to quantify the contribution of major/minor components of the energy equation towards EBR. The result highlights that the contribution of pertinent components of energy to EBR is mainly controlled by prevailing monthly hydrometeorological conditions;however, precise quantification of causes of imbalance is site-specific. A comparison between the a-posteriori analysis technique and the Bowen-ratio method demonstrates that the Bowen-ratio basically presumes a higher level of underestimation in LE. The results obtained in this study suggest that a-posteriori analysis may offer a superior methodology to correct measured eddy-correlation measurements. Furthermore, the overall trends in the correction of LE measurements suggest that there is a potential展开更多
Post-instability arthropathy may commonly develop in high-risk patients with a history of recurrent glenohumeral instability,both with and without surgical stabilization.Classically related to anterior shoulder instab...Post-instability arthropathy may commonly develop in high-risk patients with a history of recurrent glenohumeral instability,both with and without surgical stabilization.Classically related to anterior shoulder instability,the incidence and rates of arthritic progression may vary widely.Radiographic arthritic changes may be present in up to two-thirds of patients after primary Bankart repair and 30%after Latarjet procedure,with increasing rates associated with recurrent dislocation history,prominent implant position,non-anatomic reconstruction,and/or lateralized bone graft placement.However,the presence radiographic arthrosis does not predict poor patient-reported function.After exhausting conservative measures,both joint-preserving and arthroplasty surgical options may be considered depending on a combination of patient-specific and anatomic factors.Arthroscopic procedures are optimally indicated for individuals with focal disease and may yield superior symptomatic relief when combined with treatment of combined shoulder pathology.For more advanced secondary arthropathy,total shoulder arthroplasty remains the most reliable option,although the clinical outcomes,wear characteristics,and implant survivorship remains a concern among active,young patients.展开更多
文摘Hydrometeorological models are often evaluated and optimized on the basis of micrometeorological measurements. However, it has been known for more than three decades that surface measurements of sensible and latent heat energy (LE) are systematically underestimated. We studied this problem using six years of eddy-correlation measurements for four fields (corn, soybean, and prairie) in central Iowa, USA. We recorded major components of the energy equation (i.e. net radiation, sensible heat flux, LE, and soil heat flux, photosynthesis), and indirectly estimated most of the minor components of energy balance (namely storage in the soil, canopy and air). Storage in the canopy was related to leaf area index (LAI) acquired from Moderate Resolution Imaging Spectrometer (MODIS). In this paper, a diagnostic approach is investigated where systematic error is identified first. Three dimensional (3D) plots of the residual of energy equation vs. potential variables indicated the imbalance was largest mainly during the cold non-growing season when the soil was dry. Correlations between energy balance residual (EBR) and energy components showed that soil storage was not precisely estimated. Finally, an a-posteriori analysis (constrained linear multiple regression (CMLR)) was conducted to quantify the contribution of major/minor components of the energy equation towards EBR. The result highlights that the contribution of pertinent components of energy to EBR is mainly controlled by prevailing monthly hydrometeorological conditions;however, precise quantification of causes of imbalance is site-specific. A comparison between the a-posteriori analysis technique and the Bowen-ratio method demonstrates that the Bowen-ratio basically presumes a higher level of underestimation in LE. The results obtained in this study suggest that a-posteriori analysis may offer a superior methodology to correct measured eddy-correlation measurements. Furthermore, the overall trends in the correction of LE measurements suggest that there is a potential
文摘Post-instability arthropathy may commonly develop in high-risk patients with a history of recurrent glenohumeral instability,both with and without surgical stabilization.Classically related to anterior shoulder instability,the incidence and rates of arthritic progression may vary widely.Radiographic arthritic changes may be present in up to two-thirds of patients after primary Bankart repair and 30%after Latarjet procedure,with increasing rates associated with recurrent dislocation history,prominent implant position,non-anatomic reconstruction,and/or lateralized bone graft placement.However,the presence radiographic arthrosis does not predict poor patient-reported function.After exhausting conservative measures,both joint-preserving and arthroplasty surgical options may be considered depending on a combination of patient-specific and anatomic factors.Arthroscopic procedures are optimally indicated for individuals with focal disease and may yield superior symptomatic relief when combined with treatment of combined shoulder pathology.For more advanced secondary arthropathy,total shoulder arthroplasty remains the most reliable option,although the clinical outcomes,wear characteristics,and implant survivorship remains a concern among active,young patients.
