唤醒集体记忆的传统村落文化空间更新设计研究

历经城镇化的快速发展,乡村面貌非城非乡,暴露出文化空间缺失、集体记忆断层等问题。本文选取历史文化村落南焦村为更新试验点,直面为何与如何唤醒集体记忆两大核心,以“文化空间基因理论”为发力点,明晰特色资源要素的概念与分类;并在确定文化空间的典型样本后,结合融合共生的思想,遵循全链条的研究方法,实现理论与实践的有机结合,以期活化传统文化空间,唤醒村民的集体记忆,促进特色村镇的科学化保护与发展。

Development of image-based wheat spike counter through a Faster R-CNN algorithm and application for genetic studies

Spike number(SN) per unit area is one of the major determinants of grain yield in wheat. Development of high-throughput techniques to count SN from large populations enables rapid and cost-effective selection and facilitates genetic studies. In the present study, we used a deep-learning algorithm, i.e., Faster Region-based Convolutional Neural Networks(Faster R-CNN) on Red-Green-Blue(RGB) images to explore the possibility of image-based detection of SN and its application to identify the loci underlying SN. A doubled haploid population of 101 lines derived from the Yangmai 16/Zhongmai 895 cross was grown at two sites for SN phenotyping and genotyped using the high-density wheat 660 K SNP array.Analysis of manual spike number(MSN) in the field, image-based spike number(ISN), and verification of spike number(VSN) by Faster R-CNN revealed significant variation(P < 0.001) among genotypes, with high heritability ranged from 0.71 to 0.96. The coefficients of determination(R^(2)) between ISN and VSN was 0.83, which was higher than that between ISN and MSN(R^(2)= 0.51), and between VSN and MSN(R^(2)= 0.50). Results showed that VSN data can effectively predict wheat spikes with an average accuracy of 86.7% when validated using MSN data. Three QTL Qsnyz.caas-4 DS, Qsnyz.caas-7 DS, and QSnyz.caas-7 DL were identified based on MSN, ISN and VSN data, while QSnyz.caas-7 DS was detected in all the three data sets. These results indicate that using Faster R-CNN model for image-based identification of SN per unit area is a precise and rapid phenotyping method, which can be used for genetic studies of SN in wheat.

A long-term record(1995-2019)of the dynamics of land desertification in the middle reaches of Yarlung Zangbo River basin derived from Landsat data

Widespread desertification in the middle part of the Yarlung Zangbo River(YZR)basin is threatening the sustain-able development of this region.To capture this process,a method was proposed for large-scale desertification monitoring by using Landsat images from 1995 to 2019.The method used an integrated classification method combined with a hierarchical decision tree and nearest neighbor classifiers.The spatio-temporal dynamics of the desertification pattern were analyzed to assist in the detection of possible driving forces.Using validation samples collected from Google Earth high-resolution images and field investigations,the overall accuracy of the classification in 2019 was 92.3%with a Kappa coefficient of 0.84.The major results were:(1)total sandy land area in 2019 was 734.1 km^(2),which accounted for 3.7%of the study area,prominently distributed along the wide river valleys and inlets of tributaries with a strip and discontinuous pattern.Sandy land tends to be distributed in the southern aspect regions with lower elevations and that are closer to rivers;(2)sandy land areas showed two temporal stages:a gradual increase of 102.4 km^(2)from 1995 to 2015 and a large decrease of 106.8 km^(2)from 2015 to 2019;(3)newly increased sandy land was distributed in the YZR Valley,while the revegetation on sandy land occurred mainly in the Lhasa River basin and some regions in the YZR Valley;and(4)increased sandy land area of 142.1 km^(2)was mainly distributed in the southern band of the two rivers.Correspondingly,revegetation on sandy land was more effective on the northern banks of the river valleys.These findings provide guidance for implementing vegetation recovery on sandy lands and provide important insights for maintaining sustainable development.

Cyclophilin D as a potential therapeutic target of liver ischemia/reperfusion injury by mediating crosstalk between apoptosis and autophagy

Background:Liver ischemia/reperfusion(I/R)injury is a complex and multifactorial pathophysiological process.It is well recognized that the membrane permeability transition pore(mPTP)opening of mitochondria plays a crucial role in cell death after I/R injury.Cyclophilin D(CypD)is a critical positive regulator of mPTP.However,the effect of CypD on the pathogenesis of liver I/R injury and whether CypD is a potential therapeutic target are still unclear.Methods:We constructed liver-specific CypD knockout and AAV8-peptidyl prolyl isomerase F(PPIF)overexpression mice.Then,a 70%liver I/R injury model was established in mice,with 90 min of ischemia and 6 h of reperfusion.The liver function was detected by the level of serum glutamic pyruvic transaminase(alanine transaminase)and glutamic oxaloacetic transaminase(aspartate aminotransferase),the liver damage score and degree of necrosis were measured by hematoxylin and eosin(H&E)staining of liver tissues.Reactive oxygen species(ROS)staining,apoptosis,and autophagy-related molecules were used to detect apoptosis and autophagy during liver I/R.Results:The liver-specific knockout of CypD alleviated necrosis and dysfunction in liver I/R injury,by reducing the excessive production of ROS,and inhibiting cell apoptosis and autophagy.On the contrary,overexpression of CypD exacerbated I/R-induced liver damage.Conclusion:We found that the downregulation of CypD expression alleviated liver I/R injury by reducing apoptosis and autophagy through caspase-3/Beclin1 crosstalk;in contrast,the upregulation of CypD expression aggravated liver I/R injury.Therefore,interfering with the expression of CypD seems to be a promising treatment for liver I/R injury.