Manipulating Hubbard-type Coulomb blockade effect of metallic wires embedded in an insulator

Correlated states have emerged in low-dimensional systems owing to enhanced Coulomb interactions.Elucidating these states requires atomic-scale characterization and delicate control capabilities.Herein,spectroscopic imaging-scanning tunneling microscopy was employed to investigate the correlated states residing in 1D electrons of the monolayer and bilayer MoSe2 mirror twin boundary(MTB).The Coulomb energies,determined by the wire length,drive the MTB into two types of ground states with distinct...     

Inhibition of Wnt activity improves peri-implantation development of somatic cell nuclear transfer embryos

Somatic cell nuclear transfer(SCNT) can reprogram differentiated somatic cells into totipotency.Although pre-implantation development of SCNT embryos has greatly improved,most SCNT blastocysts are still arrested at the peri-implantation stage,and the underlying mechanism remains elusive.Here,we develop a 3D in vitro culture system for SCNT peri-implantation embryos and discover that persistent Wnt signals block the naive-to-primed pluripotency transition of epiblasts with aberrant H3K27me3 occup...     

A Study on Human-Computer Interaction Mechanism in an Intelligent Tutoring System

Discussion is a common and important learning process. Involvement of a virtual agent can provide adaptive support for the discussion process. Argumentative knowledge construction is beneficial to learners’ acquisition of knowledge,but the effectiveness of argumentative scaffolding in existing studies is not consistent. Based on an intelligent discussion system, a total of 47 undergraduate students took part in the experiment and they were assigned to three different conditions: content-related plus content-independent scaffolding condition, content-related scaffolding condition, and the control condition. Under the content-related and content-independent scaffolding condition, the computer agent provided an idea from semantically different categories (content-related scaffolding) according to the automatic categorization of the current contributions, and further inquired the participants about their attitudes and reasons (content-independent scaffolding). Under the condition of content-related scaffolding condition, the virtual agent only provided semantically different viewpoints. Under the control condition, the subjects expressed their opinion independently without the participation of the virtual agent. Findings revealed that compared with the control group, when the virtual agent provided semantically different ideas (content-related scaffolding), the discussion breadth (number of categories) was improved and the subjects felt that they had a more comprehensive understanding of the problem. Compared with the content-related scaffolding condition, when the virtual agent provided semantically different ideas and further asked about the attitudes and reasons, the subjects expressed more agreement with these views, but mentioned fewer categories during the discussion. This study suggests that the content-related scaffolding can facilitate the cognitive processing effect relevant to the topic of discussion. When the content independent scaffolding is added, it can promote the argumentative processing, but may have a negative effect on the cognitive processing related to the topic discussed.     

Switching Phenomena of CuTCNQ Induced Mainly by the Interaction among Microcrystaline Grains

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Intestinal microflora in rats with ischemia／reperfusion liver injury

Objectives:To investigate the intestinal microflora status related to ischemia/reperfusion(I/R)liver injury and explorethe possible mechanism.Methods:Specific pathogen free grade Sprague-Dawley rats were randomized into three groups:Controlgroup(n=8),sham group(n=6)and I/R group(n=10).Rats in the control group did not receive any treatment,rats in the I/R groupwere subjected to 20 min of liver ischemia,and rats in the sham group were only subjected to sham operation.Twenty-two hourslater,the rats were sacrificed and liver enzymes and malondialdehyde(MDA),superoxide dismutase(SOD),serum endotoxin,intestinal bacterial counts,intestinal mucosal histology,bacterial translocation to mesenteric lymph nodes,liver,spleen,andkidney were studied.Results:Ischemia/reperfusion increased liver enzymes,MDA,decreased SOD,and was associated withplasma endotoxin elevation in the I/R group campared to those in the sham group.Intestinal Bifidobacteria and Lactobacillidecreased and intestinal Enterobacterium and Enterococcus     

邓小平教育思想与高校政治思想教育

粉碎“四人帮”以后,高等学校面临着拨乱反正和恢复、发展教育的任务。恢复高考制度以后,大批经受过“文化大革命”、经受过上山下乡艰苦生活锻炼的学生,进入了高等学府。他们十分珍惜这来之不易的学习机会,学习非常自觉刻苦,学习热情空前高涨。我在清华工作的时候,深切地体会到了那几届学生的努力。“十年动乱”给学生带来思想上的创伤是不可低估的。在拨乱反正的初期,学生的思想比较混乱。“文革”带来的灾难、党过去的部分错误,造成部分学生对党的领导和社会主义制度的怀疑,究竟党能不能领导,社会主义有没有优越性,不少人感到困惑,甚至产…     

A critical review of mineral-microbe interaction and co-evolution:mechanisms and applicationsOA

Mineral-microbe interactions play important roles in environmental change,biogeochemical cycling of elements and formation of ore deposits.Minerals provide both beneficial(physical and chemical protection,nutrients,and energy) and detrimental(toxic substances and oxidative pressure) effects to microbes,resulting in mineral-specific microbial colonization.Microbes impact dissolution,transformation and precipitation of minerals through their activity,resulting in either genetically controlled or m...     

Master Embroiderers Dedicated to Solitary Pursuit of Art

Hefang Street in Hangzhou, capital city of southeast Zhejiang Province, is full of hustle and bustle, with a multitude of shops and crowds of visitors. Walk around the street corner and you will get to a quiet alley named ＂Anrong Alley＂ where Chen Shuiqin＇s embroidery studio is based. In this two-storey building, I met Ms. Chen and her disciples Yu Zhiyin and Jin Jiahong. They were embroidering on cloth attentively. The small studio was almost occupied by embroidery screens. On the window side is a row of wooden embroidery frames. Several girls coming to learn embroidery skills from different places around the country were busy with their works.     

Electrically function-switchable magnetic domain-wall memory

Versatile memory is strongly desired for end users,to protect their information in the information era.In particular,bit-level switchable memory that can be switched from rewritable to read-only function would allow end users to prevent important data being tampered with.However,no such switchable memory has been reported.We demonstrate that the rewritable function can be converted into read-only function by applying a sufficiently large current pulse in a U-shaped domain-wall memory,which compr...