Distribution of Soil Organic Carbon Fractions as Related to Land Use and Management in the Loess Plateau, Northern China

Organic C in the soil is not a uniform material but rather a complex mixture of plant, animal and microbial residues at different stages of decomposition (Post and Kwon 2000). So the dynamics of soil organic carbon (SOC) is usually described by dividing total SOC into different fractions (Six et al. 2002). Of all the different fractions, density defined fractions (light- and heavy fractions) may relate better to specific functions or processes (O’Hara et al. 2006), and the changes in SOC due to land use and management may be partly explained by the way C is allocated in these different SOC fractions (Tan et al. 2007). Previous research in the Loess Plateau of northern China indicate that, compared with the grassland restored from cropping, continuous tillage and proper management in cropland increased SOC storage in the lower soil horizons (Li et al. 2008). This study was conducted to investigate the distribution of light- and heavy fractions of SOC under cropland and grassland, aiming to better understand how the density fractions of SOC were affected by the land use conversion

Block Chain based Searchable Symmetric Encryption

The mechanism for traditional Searchable Symmetric Encryption is pay-then-use. That is to say, if a user wants to search some documents that contain special keywords, he needs to pay to the server firstly, then he can enjoy search service. Under this situation, these kinds of things will happen: After the user paying the service fees, the server may either disappear because of the poor management or returning nothing. As a result, the money that the user paid cannot be brought back quickly. Another case is that the server may return incorrect document sets to the user in order to save his own cost. Once such events happen, it needs the arbitration institution to mediate which will cost a long time. Besides, to settle the disputes the user has to pay to the arbitration institution. Ideally, we deeply hope that when the user realizes the server has a tendency to cheat in the task of searching, he can immediately and automatically withdraw his money to safeguard his right. However, the existing SSE protocols cannot satisfy this demand. To solve this dilemma, we find a compromised method by introducing the block chain into SSE. Our scheme achieves three goals stated below. Firstly, when the server does not return any thing to user after he gets the search token, the user can get some compensation from the server, because the server can infer some important information from the Index and this token. Besides, the user also doesn\u27t pay the service charge. Secondly, if the documents that the server returns are false, the server cannot receive service fees, meanwhile, he will be punished. Lastly, when the user receives some bitcoin from server at the beginning, he may terminate the protocol. Under this situation, the server is a victim. In order to prevent such thing from happening, the server will broadcast a transaction to redeem his pledge after an appointed time

Betulinic acidのラット静脈虚血進行抑制効果について

Background/Objectives: Betulinic acid is a component of a Chinese traditional herb that upregulates endothelial nitric oxide (NO) synthase (eNOS) and reduces NADPH expression. Increased production of reactive oxygen species (ROS) and reactive nitrogen species (RNS) after cerebral arterial ischemia is a major cause of neuronal damage. Local venous ischemia can arise that slowly damages surrounding brain tissue during surgical procedures. The present study investigated the effects on infarct size when betulinic acid was administered after inducing two-vein occlusion (2VO) with a slowly developing lesion in rats. Methods: We elicited 2VO in 18 male Wistar rats by the photochemical thrombosis of two adjacent cortical veins combined with KCL-induced cortical spreading depression (CSD). The rats were then randomized into groups (n=9 each) to receive either dimethyl sulfoxide (DMSO) vehicle (control) or betulinic acid (30mg/kg/day; n=9) by daily gavage for seven days, and then infarct volume and 3-nitrotyrosine expression were assessed. Results: Daily administration of betulinic acid for seven days significantly reduced infarct volume from 3.81 ± 0.7 to 1.90 ± 0.3mm³ (p=0.017). Physiological data and regional cerebral blood flow did not significantly differ between the two groups during the study. We found 3-nitrotyrosine expression within the border zone of the infarct area and cleaved caspase-3 only within the lesion at the ipsilateral hemisphere in both groups. However, 3-nitrotyrosine/caspase-3 expression did not significantly differ at any time between the groups. Conclusions: Betulinic acid reduced neuronal damage in a rat model of cerebral venous ischemia.博士（医学）・乙第1460号・令和2年6月30

Plant C, N, P Stoichiometry Was Effected with Nitrogen Deposition on the Loess Plateau, China

The mass ratio of C:N:P (Carbon: Nitrogen: Phosphorus) in plant tissue can reflect the utilization efficiency of these basic elements (Piao et al. 2005). Additionally, the N:P ratio in plant tissue can be used to detect nutrient limita-tions as N, P or both are most often the driving force for ecosystem development and change (Koerselman and Meuleman 1996). N deposition has been increasing dramatically and it has great influence on the productivity, stability and nutrient supply conditions in the terrestrial and aquatic ecosystem in recent years (Wang and Yu 2008). Many scholars have focused on the C:N:P stoichiometry of individual plant or the whole plant communities which were based on weighted average of important key species and their element contents, rather than by collecting bio-mass samples of all the plants in the community level. Moreover, less is known of the effects of N deposition on C:N:P stoichiometry characteristics of plant communities, especially the grasslands of the Loess Plateau. An experiment was set to study the effects of N deposition on C, N,P stoichiometry characteristics by simulating N deposition by way of N addition

Human rights violations in organ procurement practice in China

Over 90% of the organs transplanted in China before 2010 were procured from prisoners. Although Chinese officials announced in December 2014 that the country would completely cease using organs harvested from prisoners, no regulatory adjustments or changes in China’s organ donation laws followed. As a result, the use of prisoner organs remains legal in China if consent is obtained