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Effects of Tillage and Crop Residue Management on Maize Yields and Net Returns in the Central Mexican Highlands Under Drought Conditions

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Pedosphere 2014年第4期24卷 476-486页

作者： R.ROMERO-PEREZGROVAS N.VERHULST D.DE LA ROSA V.HERNáNDEZ M.MAERTENS j.deckers B.GOVAERTS International Maize and Wheat Improvement Center(CIMMYT) P.O.Box 6-641Mexico D.F.06600(Mexico) Department of Earth and Environmental Sciences University of LeuvenCelestijnenlaan 200 ELeuven 3001(Belgium) Mathematics Research Center(CIMAT) Jalisco S/NValencianaGuanajuatoMexico CP 36240(Mexico)

In the subtropical highlands of Central Mexico, where the main crop is maize （Zea mays）, the conventional practice （CP） involves tillage, monoculture and residue removal, leading to soil degradation and unsustainable use of natural resources and agricultural inputs. Conservation agriculture （CA） has been proposed as a viable alternative in the region, based on reduction in tillage, retention of adequate levels of crop residues and soil surface cover and use of crop rotation. This study began in 2009 when the highlands of Central Mexico suffered from a prolonged drought during vegetative maize growth in july-August, providing an opportunity for the on-farm comparison of CA with CP under severe drought conditions which 21 climate change models projected to become more frequent. Under dry conditions, CA resulted in higher yields and net returns per hectare as early as the first and second years after adoption by farmers. As an average of 27 plots under farmers＇ management in 2009, the maize yields were 26% higher under CA （6.3 t ha-1） than under CP （5.0 t ha-l）. 2010 was close to a normal year in terms of rainfall so yields were higher than in 2009 for both practices; in addition, the yield difference between the practices was reduced to 19% （6.8 t ha-1 for CA vs. 5.7 t ha-1 for CP）. When all the 2009 and 2010 observations were analyzed in a modified stability analysis, CA had an overall positive effect of 3 838 Mexican Pesos ha-1 （320 $US ha-1） on net return and 1.3 t ha-1 on yield. After only one to two years of adoption by farmers on their fields, CA had higher yields and net returns under dry conditions that were even drier than those predicted by the analyzed 21 climate change models under a climate change scenario, emission scenario A2.

关键词： climate change conservation agriculture conventional practice emission scenario modified stability analysis

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连续波式多普勒在冠心病监护病房床旁测定肺毛楔嵌压的研究

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声学技术 1991年第3期 21-22页

作者：沈学东,Vletter W B,deckers j W,Roelandt jRTC 上海医科大学中山医院心血管病研究所荷兰Enasmus大学Dijkzigt医院胸科中心荷兰Enasmus大学Dijkzigt医院胸科中心荷兰Enasmus大学Dijkzigt医院胸科中心

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不同风险水平的稳定型冠状动脉疾病患者中培哚普利的治疗效应

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世界核心医学期刊文摘（心脏病学分册） 2006年第8期2卷 28-29页

作者： deckers j. W. Goedhart D. M. Boersma E. 王亭忠(译) 任付先(校) Department of Cardiology Thoraxcenter Erasmus University Medical Center Rotterdam Dr Molewaterplein 40 3015GD Rotterdam Netherlands 不详

Aims: Patients with stable coronary artery disease(CAD) are at increased risk. Estimation of individual risk is difficult. We developed a cardiovascular risk model based on the EUROPA study population and investigated whether benefit of long-term administration of the angiotensin-con- verting enzyme(ACE)-inhibitor perindopril was modified by risk level. Methods and results: A total of 12218 patients with stable CAD were treated with 8 mg perindopril or placebo. Baseline patient characteristics were assessed for association with 1091 cardiovascular deaths or non-fatal myocardial infarction(MI). Risk factors were age over 65 years, male gender [hazard ratio(HR) 1.2], previous MI(HR 1.5), previous stroke and/or peripheral vascular disease(HR 1.7), diabetes, smoking, angina(all HR 1.5), and high serum cholesterol and systolic blood pressure. Treatment benefit by perindopril was consistent among high, intermediate, and low risk patients(HRs 0.88, 0.68, and 0.83, respectively). Risk reduction was thus not modified by absolute risk level. Conclusion: Risk factors such as age, male gender, smoking, total cholesterol, and blood pressure continue to play an important role once clinical sequellae of coronary heart disease have developed. Patients at moderate-to-high risk because of uncontrolled risk factors and those with other indications for ACE-inhibitors have the most to gain from ACE-inhibition.

关键词：稳定型冠状动脉疾病胆固醇水平风险模型疾病患者治疗效应培哚普利 ACE抑制剂血管紧张素转换酶致死性心肌梗死 EUROPA

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在心脏科门诊患者中使用便携式心脏超声装置的评价

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世界核心医学期刊文摘（心脏病学分册） 2005年第7期1卷 26-26页

作者： Vourvouri E.C. Poldermans D. deckers j.W. j.R.T.C. Roelandt 赵登峰 Dr. Department of Cardiology Thoraxcentre-H 538 Erasmus MC Dr Molewaterplein 40 3015 GD Rotterdam Netherlands

Objective: To determine the diagnostic potential of a hand carried cardiac ultrasound(HCU) device(OptiGo, Philips Medical Systems) in a cardiology outpatient clinic and to compare the HCU diagnosis with the clinical diagnosis and diagnosis with a full featured standard echocardiography(SE) system. Methods: 300 consecutive patients took part in the study. The HCU examination was performed by an experienced echocardiographer before patients visited the cardiologist. The echocardiographer noted whether the HCU device was able to confirm or reject the referral diagnosis, which abnormality was detected, and whether SE investigation was necessary. Physical examination by a cardiologist followed and thereafter, whenever required, a complete study with an SE was carried out. The HCU data were compared with the clinical diagnosis of the cardiologist and the SE diagnosis in a blinded manner. Results: The cardiologist referred 203 of 300 patients for an SE study and 13 patients for transoesophageal echocardiography. In 84 patients no further examination was considered necessary. HCU echocardiography was able to confirm or reject the suspected clinical diagnosis in 159 of 203(78%) patients. In 44 of 203(22%) patients SE Doppler was needed. Agreement between the HCU device and the SE system for the detection of major abnormalities was excellent(98%). The HCU device missed 4%of the major findings. Among the 84 patients not referred for an SE, the HCU device detected unsuspected major abnormalities missed with the physical examination in 14(17%). Conclusion: Integration of an HCU device with the physical examination augments the yield of information.

关键词：心脏科临床诊断漏诊率盲法内科专家

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