Foreign Economic Policy Formulation & Implementation in China: China-ASEAN Free Trade Agreement

Ph.DDOCTOR OF PHILOSOPH

Altered intestinal microbiota enhances adenoid hypertrophy by disrupting the immune balance

IntroductionAdenoid hypertrophy (AH) is a common upper respiratory disorder in children. Disturbances of gut microbiota have been implicated in AH. However, the interplay of alteration of gut microbiome and enlarged adenoids remains elusive.Methods119 AH children and 100 healthy controls were recruited, and microbiome profiling of fecal samples in participants was performed using 16S rRNA gene sequencing. Fecal microbiome transplantation (FMT) was conducted to verify the effects of gut microbiota on immune response in mice.ResultsIn AH individuals, only a slight decrease of diversity in bacterial community was found, while significant changes of microbial composition were observed between these two groups. Compared with HCs, decreased abundances of Akkermansia, Oscillospiraceae and Eubacterium coprostanoligenes genera and increased abundances of Bacteroides, Faecalibacterium, Ruminococcus gnavus genera were revealed in AH patients. The abundance of Bacteroides remained stable with age in AH children. Notably, a microbial marker panel of 8 OTUs were identified, which discriminated AH from HC individuals with an area under the curve (AUC) of 0.9851 in the discovery set, and verified in the geographically different validation set, achieving an AUC of 0.9782. Furthermore, transfer of mice with fecal microbiota from AH patients dramatically reduced the proportion of Treg subsets within peripheral blood and nasal-associated lymphoid tissue (NALT) and promoted the expansion of Th2 cells in NALT.ConclusionThese findings highlight the effect of the altered gut microbiota in the AH pathogenesis

Ultra-broadband near-field Josephson microwave microscopy

Advanced microwave technologies constitute the foundation of a wide range of modern sciences, including quantum computing, microwave photonics, spintronics, etc. To facilitate the design of chip-based microwave devices, there is an increasing demand for state-of-the-art microscopic techniques capable of characterizing the near-field microwave distribution and performance. In this work, we integrate Josephson junctions onto a nano-sized quartz tip, forming a highly sensitive microwave mixer on-tip. This allows us to conduct spectroscopic imaging of near-field microwave distributions with high spatial resolution. Leveraging its microwave-sensitive characteristics, our Josephson microscope achieves a broad detecting bandwidth of up to 200 GHz with remarkable frequency and intensity sensitivities. Our work emphasizes the benefits of utilizing the Josephson microscope as a real-time, non-destructive technique to advance integrated microwave electronics

The oyster genome reveals stress adaptation and complexity of shell formation

The Pacific oyster Crassostrea gigas belongs to one of the most species-rich but genomically poorly explored phyla, the Mollusca. Here we report the sequencing and assembly of the oyster genome using short reads and a fosmid-pooling strategy, along with transcriptomes of development and stress response and the proteome of the shell. The oyster genome is highly polymorphic and rich in repetitive sequences, with some transposable elements still actively shaping variation. Transcriptome studies reveal an extensive set of genes responding to environmental stress. The expansion of genes coding for heat shock protein 70 and inhibitors of apoptosis is probably central to the oyster's adaptation to sessile life in the highly stressful intertidal zone. Our analyses also show that shell formation in molluscs is more complex than currently understood and involves extensive participation of cells and their exosomes. The oyster genome sequence fills a void in our understanding of the Lophotrochozoa. © 2012 Macmillan Publishers Limited. All rights reserved

Recent Advances in Bacterial Persistence Mechanisms

The recurrence of bacterial infectious diseases is closely associated with bacterial persisters. This subpopulation of bacteria can escape antibiotic treatment by entering a metabolic status of low activity through various mechanisms, for example, biofilm, toxin–antitoxin modules, the stringent response, and the SOS response. Correspondingly, multiple new treatments are being developed. However, due to their spontaneous low abundance in populations and the lack of research on in vivo interactions between persisters and the host’s immune system, microfluidics, high-throughput sequencing, and microscopy techniques are combined innovatively to explore the mechanisms of persister formation and maintenance at the single-cell level. Here, we outline the main mechanisms of persister formation, and describe the cutting-edge technology for further research. Despite the significant progress regarding study techniques, some challenges remain to be tackled

Application of Digital Image Correlation Technique for the Damage Characteristic of Rock-like Specimens under Uniaxial Compression

The damage and degradation are the main influence factors of the instability of rock mass engineering. In this paper, the damage and deformation characteristics of the rock-like samples are investigated under the uniaxial compression test, and the advanced digital image correlation (DIC) device is devoted to full-field deformation data acquisition on the sample surface. Based on the full-field deformation data, a new damage variable is proposed by the principal strain standard deviation to characterize the uniaxial compression damage process of the rock-like samples. The results show that the newly presented damage variable can be utilized for the quantitative characterization of the sample damage. According to the characteristics of the damage variable, the damage evolution process of the rock-like specimens under uniaxial compression can be divided into four stages: initial damage closure stage, linear elastic damage stage, elastic-plastic damage stage, and plastic damage stage. From the stress-strain curve, the cut-off point from elastic to plastic deformation of the rock-like specimen is also the turning point from micro to macro damage; after the point, the apparent initial damage starts to occur on the sample surface; furthermore, the damage of the specimen is accelerated in the plastic damage stage. When the overall damage variable reaches 0.5 or the damage variable of strain localization zone reaches 0.8, the macro crack forms, and the bearing capacity of the rock-like specimen decreases rapidly. The findings are of great significance to the prediction of the damage process of rock mass engineering by digital image correlation

Geodiversity characterization of the Danxiashan UNESCO Global Geopark of China

The Danxiashan UNESCO Global Geopark (Danxiashan UGGp) is located in Shaoguan, northern Guangdong Province of South China, and was approved as such by the Global Geoparks Network in 2004. It is an ideal site for geodiversity and geoheritage studies as well as a centre for geoeducation owing to its importance in understanding the geodynamics of South China during late Mesozoic and being the most representative danxia landscape (a red beds landscape characterized by well-developed cliffs and developed dominantly on hard conglomerates and sandstones) in the humid subtropical climate of China. The methods of field investigation and literature reviews were applied to document geodiversity characterization of the Danxiashan. The study area is characterized predominately by well-developed Late Cretaceous red beds deposited in alluvial fan and desert environments within a faulted continental basin. The red beds were uplifted during the Himalayan orogenic cycle (ca. 40 Ma to present) and dissected by faulting and jointing to form prominent escarpments and a variety of erosional landforms in tandem with weathering, water erosion and rockfalls. The danxia landscape of Danxiashan is composed of mesas, peaks, cliffs, canyons, rock walls and pillars with dominant bedrock of reddish conglomerates and sandstones. It is designated as the World Heritage ‘China Danxia’ with other five sites in South China owing to its exceptionally beautiful and distinctive landscape as well as diversified geological features and landforms. As one of the earliest and best developed geoparks in China, an assessment and summary of the geodiversity of Danxiashan sets a practical example in formulating long-term strategies in geotourism and geoeducation for geopark development in China and other countries