Soil loss tolerance （/） is the maximum rate of annual soil erosion that is tolerated and still allows a high level of crop productivity to be sustained economically and indefinitely. In the black soil region of Nort...Soil loss tolerance （/） is the maximum rate of annual soil erosion that is tolerated and still allows a high level of crop productivity to be sustained economically and indefinitely. In the black soil region of Northeast China, an empirically determined, default Tvalue of 200 （t/km2.a） is used for designing land restoration strategies for different types of soils. The ob- jective of this study was to provide a methodology to calculate a quantitative T for different black soil species. A field investigation was conducted to determine the typical soil profiles of 21 black soil species in the study area and a quantitative methodology based on a modified soil productivity index model was established to calculate the Tvalues. These values, which varied from 68 t/km2.a to 358 t/km2-a, yielded an average Tvalue of 141 t/km2.a for the 21 soil species. This is 29.5% lower than the current national standard T value. Two significant factors that influenced the T value were soil thickness and vulnerability to erosion. An acceptable reduction rate of soil productivity over a planned time period of 1% is recommended as necessary for maintaining long-term sustainable soil productivity. Compared with the cur- rently used of regional unified standard T value, the proposed method, which determines T using specific soil profile indices, has more practical implications for effective, sustainable management of soil and water conservation.展开更多
Purpose:The aim of the study was to examine the influence of the surgical approach for robot-assisted laparoscopic prostatectomy(RALP)on long-term urinary continence status in the era of self-reported functional statu...Purpose:The aim of the study was to examine the influence of the surgical approach for robot-assisted laparoscopic prostatectomy(RALP)on long-term urinary continence status in the era of self-reported functional status measures using the Expanded Prostate Cancer Index Composite 26.Materials and methods:This is a prospective evaluation of 232 patients undergoing RALP between September,2019 and September,2020.Urinary continence status and postoperative incontinence(pad usage)were evaluated 12 months after RALP using Expanded Prostate Cancer Index Composite 26 questionnaires.Patients were categorized according to their surgical approach and outcome into the following groups:successful nerve sparing(NS),primarily without nerve sparing(prim.NNS),and no nerve sparing by secondary resection(NNS by SR).The median levels of their questionnaire outcomes were evaluated and compared using the Wilcoxon rank sum test with continuity correction.Results:Urinary continence status 12 months after RALP differed significantly between the NS and prim.NNS(p=0.0071)and the NS and NNS by SR(p=0.0076)groups.There was no significant difference between the prim.NNS and NNS by SR(p=0.53)groups.Pad usage 12 months after RALP had no significant difference with regard to SR of the neurovascular bundle(p=0.14).Conclusions:Patient-reported outcomes of long-term urinary continence status seem to show no difference in postoperative continence,regardless of whether a non-nerve-sparing result was planned or reached through SR.Instead,preservation of neurovascular bundle seems to lead to better long-term continence rates.展开更多
基金Supported by National Science Foundation of China(40672172,40972166)Major State Basic Research Development Program of China(973 Program)(2010CB428804)+1 种基金the Major Science and Technology Program for Water Pollution Control and Treatment(2009ZX07212-003)the Major Science and Technology Program of Beijing(D09040903700801)
基金Foundation： National Natural Science Foundation of China, No.40671111 No.41101267 Nonprofit Sector Special Funds of the Ministry of Water Resources of China, No.2010332030
文摘Soil loss tolerance （/） is the maximum rate of annual soil erosion that is tolerated and still allows a high level of crop productivity to be sustained economically and indefinitely. In the black soil region of Northeast China, an empirically determined, default Tvalue of 200 （t/km2.a） is used for designing land restoration strategies for different types of soils. The ob- jective of this study was to provide a methodology to calculate a quantitative T for different black soil species. A field investigation was conducted to determine the typical soil profiles of 21 black soil species in the study area and a quantitative methodology based on a modified soil productivity index model was established to calculate the Tvalues. These values, which varied from 68 t/km2.a to 358 t/km2-a, yielded an average Tvalue of 141 t/km2.a for the 21 soil species. This is 29.5% lower than the current national standard T value. Two significant factors that influenced the T value were soil thickness and vulnerability to erosion. An acceptable reduction rate of soil productivity over a planned time period of 1% is recommended as necessary for maintaining long-term sustainable soil productivity. Compared with the cur- rently used of regional unified standard T value, the proposed method, which determines T using specific soil profile indices, has more practical implications for effective, sustainable management of soil and water conservation.
文摘Purpose:The aim of the study was to examine the influence of the surgical approach for robot-assisted laparoscopic prostatectomy(RALP)on long-term urinary continence status in the era of self-reported functional status measures using the Expanded Prostate Cancer Index Composite 26.Materials and methods:This is a prospective evaluation of 232 patients undergoing RALP between September,2019 and September,2020.Urinary continence status and postoperative incontinence(pad usage)were evaluated 12 months after RALP using Expanded Prostate Cancer Index Composite 26 questionnaires.Patients were categorized according to their surgical approach and outcome into the following groups:successful nerve sparing(NS),primarily without nerve sparing(prim.NNS),and no nerve sparing by secondary resection(NNS by SR).The median levels of their questionnaire outcomes were evaluated and compared using the Wilcoxon rank sum test with continuity correction.Results:Urinary continence status 12 months after RALP differed significantly between the NS and prim.NNS(p=0.0071)and the NS and NNS by SR(p=0.0076)groups.There was no significant difference between the prim.NNS and NNS by SR(p=0.53)groups.Pad usage 12 months after RALP had no significant difference with regard to SR of the neurovascular bundle(p=0.14).Conclusions:Patient-reported outcomes of long-term urinary continence status seem to show no difference in postoperative continence,regardless of whether a non-nerve-sparing result was planned or reached through SR.Instead,preservation of neurovascular bundle seems to lead to better long-term continence rates.
