基于旅行费用法的衢州市柯城区“一村万树”工程生态旅游服务价值评估

生态旅游服务价值作为生态系统生产总值（Gross Ecosystem Product，GEP）的重要组成部分，是生态产品价值实现的重要途径。以衢州市柯城区"一村万树"实施区为研究区域，采用国际上普遍认可的旅行费用区间法（Travel Cost Interval Analysis，TCIA）进行了问卷调查，开展了生态旅游服务的价值核算；同时基于计量经济学原理构建了游客随机效用模型（Random Utility Model，RUM），探究了不同自然地理属性对游客生态旅游选址决策的影响。结果表明：（1）2018年"一村万树"实施区的生态旅游服务总价值约19.29亿元，单位面积生态旅游价值量为8.37万元/hm²；（2）2018年"一村万树"实施区的游客人均游憩价值为713.89元，只占整个柯城区人均游憩价值（1204.58元）的59.3%，说明其还有较大的生态产品价值实现提升空间；（3）柯城区游客人均游憩价值远高于当地文化旅游局提供的621.80元的旅游人均消费支出，说明游客时间成本和消费者剩余蕴含了丰富的潜在价值，需要在评估时予以考虑；（4）随机效用模型结果显示，目的地旅行费用与游客访问呈负相关，森林和湿地面积均与游客访问呈正相关，且湿地的相对贡献远高于森林。研究结果对"一村万树"实施区有针对性地进行生态保护、管理和开发具有指导意义，对提高GEP核算的准确性和探索生态产品价值实现的机制具有借鉴意义。     

超级植物糖棕

正人类的追求永无止境,总希望找到一些"超级植物",既能满足日常需要,又易于栽培收获,最好还能有一点文化寄托。这听上去有点不可思议,然而这样的"超级植物"还真的存在。古往今来,中国人找到了大豆和茶、北美原住民找到了玉米、安第斯山的居民找到了玛咖、埃塞俄比亚人找到了咖啡。最终这些超级植物     

Association between VDR Apal Polymorphism and Hip Bone Mineral Density Can Be Modified by Body Mass Index:A Study on Postmenopausal Chinese Women

Osteoporosis is a major public health problem for old people.Genetic factors are considered tobe major contributors to the pathogenesis of postmenopausal osteoporosis.The vitamin D receptor(VDR)gene is a prominent candidate gene for the regulation of postmenopausal bone mass;however,despite exten-sive studies,controversy remains regarding its association with postmenopausal body mineral density(BMD)variation.In this study,a total of 260 healthy postmenopausal Chinese women were genotyped at the VDRApaI locus using polymerase chain reaction(PCR)-restriction fragment length polymorphism (RFLP).Rawhip BMD was significantly associated with VDR ApaI polymorphism with and without adjusting for age(P=0.015 and 0.040,respectively).This genetic effect can explain 3.32% of hip BMD variation.However,the significant association vanished after correcting for both age and body mass index(BMI)(P=0.169).Inaddition,we observed a significant association between VDR ApaI polymorphism with unadjusted BMI(P=0.042)or BMI adjusted for age(P=0.049).The raw hip BMD was also found to be significantly corre-lated with BMI(r=0.517,P=0.0001),with BMI explaining 26.35% of the variation of hip BMD.All of thesefacts prompt us to conclude that the significant association between the VDR ApaI genotype and hip BMDmay be modified by BMI in postmenopausal Chinese women.Our findings may partially explain the earlierinconsistent association results concerning the VDR gene and BMD,and highlight the importance of incorpo-rating covariates such as BMI into osteoporosis association studies.     

The Modulation and Control of the Gecko''''s Foot Movement

1IntroductionAttachment is still a difficult problem in wall-climbing robotics.There are two main types ofattachment mechanisms for wall climbing robots.One issuction,which has major drawbacks.The mechanismrequires the contacting surface being smooth,otherwise itwill be ineffective.This limits adhesion of the suctioncup to relatively smooth,non-porous,non-crackedsurfaces.Another issue associated with suction adhesionis that this method requires time to develop enoughvacuum to generate suffici…     

adjuvant chemotherapy group, 56 patients received a

1%,26.6% and 27.7% respectively.there was no significant discrepancy(P>0.05).The 5-year survival in 3 or 4 cycles patients were 26.7% and the 5-year survival in 5 or 6 cycles patients were 28.9% .there was no significant discrepancy(P>0.05).Conclusion:Postoperative adjuvant chemotherapy with platinum-based regimen for 3 or 4 cycles can improve survival rate for stage Ⅲ NSCLC patients.Non-small-cell lung cancer; Surgery; Adjuvant chemotherapy; Survival rate0临床肿瘤学杂志Chinese Clinical Oncology19-21R734.2E0724E;E072_4潘泓;173-175长春瑞滨联合卡铂治疗老年晚期非小细胞肺癌胡兴胜;张湘茹;储大同; 中国医学科学院     

我国近海龟足3个地理群体比较转录组及环境适应性研究

龟足(Capitulum mitella)隶属于节肢动物门(Arthropoda)指茗荷科(Pollicipedidae)龟足属，广泛分布于亚热带及热带近海沿岸中高潮地带。由于龟足生存环境复杂多变，可能导致其不同地理群体形成与其生境相适应的特征。本研究基于高通量测序技术对浙江舟山、福建宁德和广东珠海3个典型海域的龟足进行比较转录组分析，并利用生物信息学方法探究3个地理群体对环境的适应机制。结果表明，3个地理群体间存在651个(广东珠海和福建宁德群体间)至3 738个(浙江舟山和福建宁德群体间)数量不等的差异表达基因(DEGs)，主要涉及核糖体合成、抗原加工与递呈、分子伴侣代谢通路。基因序列的非同义替换率(K_a)和同义替换率(K_s)之间的比例K_a/K_s，如果其超过1，则认为有正选择压力作用于该基因，基因正在快速进化。3个地理群体间龟足直系同源基因正选择压力分析结果显示，254个直系同源基因中有7个基因受到正选择压力，包括D-天冬氨酸酶基因(K_a/K_s=2.0...     

基因编辑技术对大肠杆菌yjjW基因点突变的两步法策略

[目的]为了实现对大肠杆菌靶基因的点突变,本研究将同源重组系统与CRISPR-Cas9技术相结合,探索一种高效、简捷的两步法策略.[方法]将靶基因的上下游同源臂和标记基因(amp)与pKOV质粒连接,获得pKOV-HR重组质粒.将pKOV-HR转化至大肠杆菌,借助其自身RecA重组系统,介导DNA发生同源重组,获得靶基...