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Tan, Qing

Publications and source records attributed to Tan, Qing.

A compendium of multi-omics data illuminating host responses to lethal human virus infections

Human infections caused by viral pathogens trigger a complex gamut of host responses that limit disease, resolve infection, generate immunity, and contribute to severe disease or death. Here, we present experimental methods and multi-omics data capture approaches representing the global host response to infection generated from 45 individual experiments involving human viruses from the Orthomyxoviridae, Filoviridae, Flaviviridae, and Coronaviridae families. Analogous experimental designs were implemented across human or mouse host model systems, longitudinal samples were collected over defined time courses, and global multi-omics data (transcriptomics, proteomics, metabolomics, and lipidomics) were acquired by microarray, RNA sequencing, or mass spectrometry analyses. For comparison, we have included transcriptomics datasets from cells treated with type I and type II human interferon. Raw multi-omics data and metadata were deposited in public repositories, and we provide a central location linking the raw data with experimental metadata and ready-to-use, quality-controlled, statistically processed multi-omics datasets not previously available in any public repository. This compendium of infection-induced host response data for reuse will be useful for those endeavouring to understand viral disease pathophysiology and network biology.

60 APPLIED LIFE SCIENCES↗

Hypergraph Models of Biological Networks to Identify Genes Critical to Pathogenic Viral Response

Motivation: Representing biological networks as graphs is a powerful approach to reveal underlying patterns, signatures, and critical components from high-throughput biomolecular data. However, graphs do not natively capture the multi-way relationships present among genes and proteins in biological systems such as protein complexes, metabolic reactions, and signal transduction pathways. Hypergraphs are generalizations of graphs that naturally model multi-way interactions in data, and we therefore seek to understand how they can more faithfully identify, and potentially predict, complex relationships in genomic expression data sets. Results: We compiled a novel data set of transcriptional host response to pathogenic viral infections and formulated relationships between genes as a hypergraph where hyperedges are differentially expressed genes and vertices represent conditions. We find that hypergraph betweenness centrality is a superior method for identification of genes important to viral response when compared with graph centrality. Our results demonstrate the utility of using hypergraphs to represent complex biological systems, and highlight potentially interesting biological results about host response to highly pathogenic viruses.

systems biology, hypergraph, viral infection, biol↗

Surface Integrity and Oxidation of a Powder Metallurgy Ni-Based Superalloy Treated by Laser Shock Peening

Laser shock peening is a mechanical surface treatment which can induce large compressive residual stresses and microstructural changes in the material by using repetitive shocks from laser pulses. In this work, the surface integrity (surface microstructure, topography, hardness and residual stress) of a laser shock peening treated powder metallurgy Ni-based superalloy was investigated. Laser shock peening treatment introduces large plastic deformation especially at a depth of about 100 μm from the surface, which increases the local hardness. The residual stress from the surface to the interior of the sample was investigated by synchrotron X-ray diffraction. The maximum compressive stress reaches 400 MPa at the surface, while the depth of the compressive stress is about 0.7 mm. Lastly, the oxidation behavior of the treated and untreated samples was evaluated by thermal exposure at 700°C for 312 h. The LSP treatment decreased the thickness of oxide layer, thereby showing improved oxidation resistance.

36 MATERIALS SCIENCE↗

A brittle fracture mechanism in thermally aged duplex stainless steels revealed by in situ high-energy X-ray diffraction

A direct relationship between the microstructural evolution and macroscopic fracture behaviors of a thermally aged (at 475 °C for 400 h) duplex stainless steel (DSS) has been established with experimental results from atom probe tomography (APT), nanoindentation and in situ synchrotron-based high-energy X-ray diffraction (HE-XRD). Furthermore, the APT experiments demonstrate that ferrite in DSS spinodally decomposes into Cr-enriched and Cr-depleted domains during thermal aging, which leads to a severe hardening effect in ferrite. The lattice strain development during deformation acquired with the in situ HE-XRD measurements confirms the cleavage fracture of α{110} and α{200} ferrite grains aligned perpendicular to loading direction. The thermally aged DSS can be readily fractured by connecting the cleavage cracks in ferrite. Conclusively, the spinodal-decomposition-induced hardening in ferrite and the premature failure of ferrite control the final brittle fracture in the aged DSS.

36 MATERIALS SCIENCE↗

In situ high-energy X-ray diffraction investigation of the micromechanical behavior of Fe-0.1C-10Mn-0/2Al steel at room and elevated temperatures

The micromechanical behavior of medium-Mn transformation-induced-plasticity (TRIP) steels with nominal chemical compositions of Fe-0.1C-10Mn (mass%) (0Al steel) and Fe-0.1C-10Mn-2Al (mass%) (2Al steel) fabricated by intercritical annealing 600 degrees C for 1 h and 650 degrees C for 1 h, respectively, was investigated using in situ high-energy X-ray diffraction (HE-XRD) with uniaxial tensile tests at 25 degrees C and 100 degrees C. We found that Liiders band propagation promoted lower volume fraction of austenite transformation to martensite in 0Al steel than 2Al steel at 25 degrees C while higher volume fraction of austenite transformation to martensite in 0Al steel than 2Al steel at 100 degrees C. Portevin-Le Chatelier (PLC) band propagation promoted higher volume fraction of austenite transformation to martensite in 0Al steel than 2Al steel during deformation at 25 degrees C and 100 degrees C. Moreover, the addition of Al obviously suppresses the formation of intermediate epsilon martensite during tensile deformation, thus the zigzag change in lattice strain of austenite was completely depressed in 2Al steel. Due to the controlled stability of metastable austenite, the 2Al steel demonstrated the best combination of ultimate tensile strength and total elongation at 25 degrees C.

36 MATERIALS SCIENCE↗

Implementing Nationally Determined Contributions: Building Energy Policies in India’s Mitigation Strategy

The Nationally Determined Contributions (NDCs) are allowing countries to examine options for reducing emissions through a range of domestic policies. Here we use the Global Change Assessment Model to demonstrate the potential impacts of energy policies and discuss strategies to implement India’s NDC with a focus on the buildings sector. Buildings are the largest end-use sector globally, and building energy consumption is expected to increase as income grows in developing countries. We find that implementing a range of energy efficiency policies robustly can reduce total Indian building energy use by 22% and lower total Indian carbon dioxide emissions by 9% in 2050 compared to the business as usual scenario. Among various policies, energy codes for new buildings can result in the most significant savings. For all energy efficiency policies, well-coordinated, consistent implementation is critical, which requires coordination across different departments and agencies, improving capacity of stakeholders, and developing appropriate institutions to facilitate policy implementation. Renewable energy deployment can also reduce carbon emissions from buildings, and incentives in the short term are important to ensuring strong market uptake. Effective development and implementation of building energy policies could help avoid lock-in of carbon-intensive infrastructure, while improving living standards and generating health benefits.

Yu, Sha↗

Manipulating Band Structure through Reconstruction of Binary Metal Sulfide for High‐Performance Thermoelectrics in Solution‐Synthesized Nanostructured Bi 13 S 18 I 2

Abstract Reconstructing canonical binary compounds by inserting a third agent can significantly modify their electronic and phonon structures. Therefore, it has inspired the semiconductor communities in various fields. Introducing this paradigm will potentially revolutionize thermoelectrics as well. Using a solution synthesis, Bi 2 S 3 was rebuilt by adding disordered Bi and weakly bonded I. These new structural motifs and the altered crystal symmetry induce prominent changes in electrical and thermal transport, resulting in a great enhancement of the figure of merit. The as‐obtained nanostructured Bi 13 S 18 I 2 is the first non‐toxic, cost‐efficient, and solution‐processable n‐type material with z T =1.0.

Xu, Biao↗

Integrating Band Structure Engineering with All-Scale Hierarchical Structuring for High Thermoelectric Performance in PbTe System

We investigated PbTe 1-x Se x -2%Na-y%SrTe system and report a high ZT of 2.3 at 923 K for PbTe 0.85 Se 0.15 -2%Na-4%SrTe. This is achieved by performing electronic band structures modifications as well as all-scale hierarchical structuring and combining the two effects. We find that high ZTs in PbTe 0.85 Se 0.15 -2%Na-4%SrTe are possible at all temperature from 300K to 873K with an average ZT ave of 1.23. The high performance in PbTe 1-x Se x -2%Na-y%SrTe could be achieved by either choosing PbTe-2Na-4SrTe or PbTe 0.85 Se 0.15 -2Na as a matrix. At room temperature the carrier mobility shows negligible variations as SrTe fraction is increased, however the lattice thermal conductivity is significantly reduced from ~ 1.1 Wm-1K-1 to ~ 0.82 Wm -1 K -1 when 5.0 % SrTe is added. The lattice thermal conductivity at 923 K decreases from ~ 0.59 Wm-1K-1 to ~ 0.43 Wm -1 K -1 . The power factor maxima of PbTe 1-x Se x -2Na-4SrTe shift systematically to higher temperature with rising Se fractions due to bands divergence. The maximum power factors reach ~ 27 μWcm -1 K -2 , ~ 30 μWcm -1 K -2 , ~ 31 μWcm -1 K -2 for the x = 0, 0.05, and 0.15 samples peak at 473K, 573K and 623K,

36 MATERIALS SCIENCE↗