松嫩平原自然宜垦性及耕地后备资源开发潜力

［目的］为保障我国粮食安全，为耕地后备资源的合理开发利用提供科学依据，同时完善中国区域耕地后备资源自然开发潜力方面的研究。［方法］文章从自然适宜性的角度出发，选取了地形、气候、土地类型和土壤4个方面15个评价因子，采用层次分析、专家打分等方法确定评价因子权重，构建松嫩平原宜垦性评价指标体系。［结果］（1）1980—2015年松嫩平原自然宜垦性整体较好，最适宜垦区与较适宜垦区占松嫩平原面积的5068%，分布在松嫩平原腹地大部地区，中部、中北部、中南部等地；(2)松嫩平原已开垦耕地资源中，持续利用耕地占松嫩平原面积的4814%，空间上与宜垦程度高值区高度吻合；(3)新增耕地占区域面积的126%，以中度适宜垦区和较适宜垦区为主；(4)松嫩平原耕地后备资源占松嫩平原土地面积的1556%，在松嫩平原西部地区、中部和东北部地区均有分布，耕地后备资源中度及以上宜垦区占后备资源总量的7465%。［结论］目前大庆市和白城市可开发耕地后备资源最为丰富，但其中轻度及不适宜开垦区所占比例大，开发难度较大； 松原市可开发资源相对丰富且开垦难度小。     

Nowcasting South African gross domestic product using a suite of statistical models

Given lags in the release of data, a central bank must ‘nowcast’ current gross domestic product (GDP) using available quarterly or higher frequency data to understand the current state of economic activity. This paper uses various statistical modelling techniques to draw on a large number of series to nowcast South African GDP. We also show that GDP volatility has increased markedly over the last 5 years, making GDP forecasting more difficult. We show that all the models developed, as well as the Reserve Bank's official forecasts, have tended to overestimate GDP growth over this period. However, several of the statistical nowcasting models we present in this paper provide competitive nowcasts relative to the official Reserve Bank and market analysts' nowcasts.     

基于BD-GIS耦合模型的北京奥林匹克 森林公园景观优化策略研究

随着城市人口的增加和人们健康意识的增强，近年 来城市公园的使用率呈现迅速上升趋势。手机等智能电子设备 的高速发展，使人们可以在户外运动中监测自身活动轨迹、距 离和能量消耗等。以北京奥林匹克森林公园为例，通过手机 信令、微博、百度POI等大数据与GIS技术结合，构建依托大 数据的GIS耦合模型，从游人的行为需求出发对公园的慢跑游 线、景点热度、游人空间分布等进行使用后量化评价，并针对 问题提出北京奥林匹克森林公园的景观优化策略。结果显示大 数据与GIS的结合可以为公园的景观优化提供客观且理性的整 改依据，从而更科学地指导城市公园的景观提升。     

苯醚甲环唑在猕猴桃中的残留动态及安全性评价

为摸清猕猴桃中有毒有害物质的残留动态,确保出口产品质量安全符合主要贸易国官方要求,本文采用气相色谱-质谱法,测定施药后不同时期苯醚甲环唑在猕猴桃果实中的残留量,并依据残留消解动态,按照欧盟和日本食品安全卫生标准,对10%苯醚甲环唑水分散粒剂的使用安全性进行评价。结果表明,苯醚甲环唑在猕猴桃中的残留量随着时间的推移逐渐下降,动态曲线符合一级动力学方程C_t=0.5359e^-0.184t,半衰期为3.767 d,属易消解农药;按照欧盟和日本猕猴桃农药最大残留限量要求,10%苯醚甲环唑水分散粒剂按照推荐剂量单次施药,10天后采摘食用是安全的。     

The Evolving Structure of Chinese R&D Funding and its Implications for the Productivity of Agricultural Biotechnology Research

China’s research and development (R&D) policy has changed considerably over recent decades, and great changes occurred in 2006 when the main programme objective of China’s R&D changed from the 863 Programme and 973 Programme to the National Science and Technology Major Project. One topic that has drawn extensive attention is whether the investment reform improved R&D productivity in China. Using a unique panel dataset from 160 universities, this paper examines the effect of the investment reform on productivity improvement in China’s agricultural biotechnology sector. We use a panel count data model with a dynamic feedback mechanism to model the knowledge production process. Strong evidence indicates that the investment reform greatly contributes to knowledge output production in China’s agricultural biotechnology sector. We also find that the input quality is more important than the absolute quantity; human research capacity exhibits the greatest contribution to the output of patents; past knowledge accumulation helps produce more patents; and entry barriers to patent production exist in China’s agricultural biotechnology sector. Moreover, the patent explosion in China may have been largely caused by improvements in the human capital input quality.     

新时代中国城市土地集约利用若干问题的再认识

研究目的：基于中国城市土地集约利用研究现状，面向新时代要求，重新审视与厘清城市土地集约利用理论认知、评价标准、影响机制和优化调控等基本问题，为中国土地集约利用的理论完善和实践创新提供支撑。研究方法：理论分析法和推理演绎法。研究结果：（1）城市土地集约利用在理论认知上应由“三个阶段”转向“三个时期”；（2）城市土地利用集约度的评价标准应由静态指标转向动态耦合；（3）城市土地集约利用的影响机制研究应由封闭区域转向关联传导；（4）城市土地集约利用优化调控策略应由极限集约转向最优集约。研究结论：进入新时代，城市土地集约利用理论上可实现“不增地，多增效”甚至“地减量，效增加”，未来相关研究应重点关注存量和减量规划中建设用地与经济发展之间关系的变化特征，以及国土空间规划与土地利用计划管理改革下新的城市土地集约利用问题。国家相关规程中的集约评价标准须结合区域发展阶段进行“匹配性”修正，政策制定要考虑区域间的“关联性”和“传导性”进行精准化设计，治理方案应按照最优集约度的“动态性”进行差异化调控。     

Budget impact analysis of secukinumab versus adalimumab in the treatment of ankylosing spondylitis

Background: Biologic treatments have enhanced the treatment outcomes of patients with active ankylosing spondylitis (AS). Until recently, TNF-alpha-inhibitors have been the only biologics approved for the treatment of active AS. The objective of this study was to assess the potential financial impact of the first non-TNF-alpha biologic secukinumab (fully human IL-17A-inhibitor) vs adalimumab (TNF-alpha-inhibitor) in the treatment of AS in Finland.

Materials and methods: In this model-based budget impact analysis, patients were treated either with secukinumab (150?mg) or adalimumab (40?mg). The number of patients and market share of different biologics were based on national reimbursement registry data. Adalimumab was the most commonly used biologic treatment for AS, and in the base case analysis all adalimumab patients are assumed to switch to secukinumab. Response rates were based on a matching-adjusted indirect comparison between secukinumab and adalimumab. Patients not achieving response were switched to another biologic treatment.

Results: Treating AS patients with secukinumab instead of adalimumab leads to potential savings of 18.2 million euros within a 5-year time period. The total costs within the follow-up time were 59.5 million euros and 77.7 million euros with and without secukinumab, respectively. According to sensitivity analyses, a higher adoption rate of secukinumab corresponds to higher potential savings.

Conclusions: Secukinumab is a cost-saving treatment option compared with adalimumab in the treatment of AS in Finland. More patients could be treated with a biologic by allocating resources more efficiently.     

Spatial and temporal analyses of potential land use conflict under the constraints of water resources in the middle reaches of the Heihe River

With the rapid urbanization in China, land resources are becoming increasingly scarce. Identifying and resolving land use conflict is essential for reasonably using land resources and achieving land sustainability. Taking the middle reaches of the Heihe River as an example, we included the constraints of local water resources to construct a multi-criteria evaluation system for assessing land use competitiveness in 2000 and 2015 based on land use, socio-economic, and nighttime light data. By comparing the competitiveness of cultivated land, construction land and ecological land, we then derived the spatiotemporal patterns of potential land use conflicts. Actual land use changes supported the hypothesis that land use tended to convert into the type with higher competitiveness at areas with intense conflict, which better indicated that our assessment model was effective. The results showed that the potential land use conflict was more acute in the central and northwest but weak in the southeast and northeast, and its pattern showed a significantly positive spatial autocorrelation. The conflict between cultivated land and construction land was most prominent and mainly occurred in the transitional zone from urban to rural areas. Rapid urban development and water shortage were the main causes of the potential land use conflict. Assessing land use multi-functions and making a tradeoff among ecological, economic, and social services will be an effective way to guide future land use to solve land use conflict. Our research provides scientific evidence for sustainable land use planning and management in the arid areas.     

乡村振兴背景下浙江省绿色农业发展评价研究*——基于农业资源综合利用的视角

［目的］在系统梳理浙江省绿色农业发展进程基础上，文章从农业资源综合利用的视角，基于经济社会发展、资源减量投入、资源循环利用和资源环境安全4个维度构建绿色农业综合评价指标体系，并评价浙江省绿色农业发展水平。［方法］借鉴BPEIR概念模型构建浙江绿色农业生产系统概念模型和评价指标体系，采用灰色关联分析法并结合宏观统计数据，从动态视角评价了2002—2016年浙江省绿色农业发展状况，并静态比较2015年浙江省11个地级市农业绿色发展的基本状况。［结果］浙江省绿色农业资源综合利用指数呈波动上升趋势，在不同的发展阶段，农业资源综合利用指数也呈现出规律性变化； 浙北地区绿色农业资源综合利用指数明显高于浙南地区； 杭州、嘉兴、宁波位居前三，金华市绿色农业资源综合利用指数最低。［结论］浙江绿色农业发展水平呈不断上升趋势，不同地区差异明显； 实行差异发展、完善政策体系、提高质量品牌、强化科技支撑是推进浙江农业绿色发展的关键。     

An evaluation of contemporary China’s land use policy – The Link Policy: A case study from Ezhou,Hubei Province

Economic reform in China has resulted in rapid urbanisation over the past three decades, changing the urban and rural landscape dramatically. A large amount of farmland was developed, leading to conflict between construction demand and farmland protection. In response, the “Link Policy” was proposed in 2005 that seeks to concurrently preserve farmland while providing for urban expansion through land exchange. The effectiveness of the Link Policy has not been systematically investigated. The purpose of this study is to analyse and evaluate outcomes of the Link Policy objectives from both a participant and investigator’s interpretive perspective. Ezhou, the first experimental city to implement the Link Policy in Hubei Province in central China, was selected as a case study area. Eight different communities in Ezhou were visited and 160 semi-structured interviews were conducted with resettled rural residents in March 2016. A combination of interviews and investigator field observations were used to evaluate the Link Policy objectives. The results show that participants recognize and support improving rural living conditions and coordinating urban-rural development, but the Link Policy failed to achieve the objectives of preserving farmland, protecting farmers’ land use rights and interests, and facilitating agricultural production. Participants perceived concentrated resettlement communities to be more efficient in land use compared to more expansive rural settlements, but vacant apartments for commercial use in resettlement areas account for a large proportion of land suggesting inefficiency in the land exchanges. We suggest policy changes to achieve more successful implementation of the Link Policy.