RESUMEN
The characteristics of ammonia volatilization and nitrous oxide emission from a paddy soil were examined under 9-year application of different slow/controlled release urea with the common large granule urea (U) as the control. The results showed that compared with the control, all slow/controlled release urea treatments, except 25.8% increase of ammonia volatilization under 1% 3,4-dimethylpyrazole phosphate (DMPP)+U, could decrease the ammonia volatilization. Polymer coated urea (PCU) dominated the highest reduction of 73.4% compared to U, followed by sulfur coated urea (SCU) (72.2%), 0.5% N-(N-butyl) thiophosphoric triamide (NBPT)+1% DMPP+U (71.9%), 1% hydroquinone (HQ)+3% dicyandiamide (DCD)+U (46.9%), 0.5% NBPT+U (43.2%), 1% HQ +U (40.2%), 3% DCD+U (25.5%), and the ammonia volatilization under different slow/controlled release urea treatments were statistically lower than that of U (P<0.05). 1% DMPP+U caused the lowest emission of N2O under different slow/controlled release urea treatments. The slow/controlled release urea also had a significant potential of N2O emission reduction: 1% DMPP+U showed the highest reduction of 74.9% compared to U, followed by PCU (62.1%), 1% HQ+3% DCD+U (54.7%), 0.5% NBPT+1% DMPP+U (42.2%), 3% DCD+U (35.9%), 1% HQ +U (28.9%), 0.5% NBPT+U (17.7%), SCU (14.5%), and N2O emissions under different slow/controlled release urea treatments were statistically lower than that of U (P<0.05). The comprehensive analysis showed that 0.5% NBPT+1% DMPP+U, SCU and PCU had similar effects on decreasing the ammonia volatilization and N2O emission and were remarkably better than the other treatments. The slow release urea with the combination of urease and nitrification inhibitors should be the first choice for reducing N loss and environmental pollution in paddy field, in view of the higher costs of coated urea fertilizers.
Asunto(s)
Agricultura , Amoníaco/análisis , Fertilizantes , Óxido Nitroso/análisis , Suelo/química , Urea/administración & dosificación , Guanidinas , Oryza , Ureasa , VolatilizaciónRESUMEN
OBJECTIVE: To explore the reduction and clinical effect in the near future of percutaneous K-wire relative poking reduction techniques for difficult to reduction of complex insert and forward angulation femoral neck fracture. METHODS: The clinical data of traumatic femoral neck fractures treated in our hospital from January 2012 to September 2015 were retrospective analysis, 15 patients with skeletal traction and distal elevation still can not eliminate the fracture angulation deformity were treated by percutaneous K-wire relative poking reduction technique to correct the angular and using cannulated screw fixation, including 5 males and 10 females, aged from 44 to 72 years with an average of 60.06 years old. The fractures were Garden type III. The reduction effect was evaluated according to Garden alignment index and clinical evaluation in the near future outcome was assessed according to Harris Hip Score. RESULTS: All patients were healed by first intention without pulmonary infection and deep vein thrombosis. The patients were followed up for 6 months to 3 years, all the fractures healed, and 1 case had limited necrosis of the femoral head. According to Garden alignment index, 14 cases were level I reducation, and 1 case was level II. Limb shortening was 1 to 5 mm with an average of (2.73±1.37) mm. Functional evaluation according to Harris score standard, at the latest follow-up the average value of pain, function, deformity and joint activity were 42.1±2.5, 37.2±4.6, 3.2±0.5, 4.1±0.3, the total average value was 86.6±9.5;13 cases were excellent, 1 case was good, 1 case was poor. CONCLUSIONS: Percutaneous K-wire relative poking reduction technique to correct the difficult to reduction of complex insert and forward angulation of the femoral neck fracture is simple, repeatable, and achieve the precision of the reset;the effect of blood supply of the hip joint is small, which provides favorable conditions for fracture healing.
Asunto(s)
Fracturas del Cuello Femoral/cirugía , Fijación Interna de Fracturas/métodos , Adulto , Anciano , Tornillos Óseos , Hilos Ortopédicos , Femenino , Fracturas del Cuello Femoral/clasificación , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Tracción , Resultado del TratamientoRESUMEN
OBJECTIVE: To analyze the cause of the postoperative shortening in distal radius fractures and to find treatment strategies to enhance the reduction effect of distal radius fracture and long-term efficacy. METHODS: From June 2005 to January 2009, 46 patients with distal radius fractures were treated by surgical operation including 17 males and 29 females,ranging from 27 to 90 years old with an average age of 48 years. All fractures were reduced satisfactory with smooth articular surface. The postoperative radial shortening was analyzed. RESULTS: All patients were followed-up for 6 to 24 months with an average of 14 months. Among them, 12 patients had radial shortening. The causes of postoperative radial shortening includes: (1) patients older than 60 years; (2) severe osteoporosis; (3) preoperative displacement and comminuted fractures; (4) inappropriate fixation methods; (5) inadequate bone graft; (6) premature load. CONCLUSION: The key points to enhance the treatment outcomes include precise judgement of the fracture type and bone quality, sufficient bone graft, firmly fixed after anatomical reduction and an appropriate plan for early loadless functional exercise. Traumatic arthritis may be avoided or delayed if the above-mentioned six causes can be taken into consideration or preventive measures can be taken.