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Using supercritical carbon dioxide (S-CO2) Brayton cycle instead of the traditional steam Rankine cycle is a promising technique to enhance the coal-fired power generation efficiency. Researchers from all over the world are actively designing and exploring efficient S-CO2 coal-fired power plants in recent years with great efforts made to overcome the significant technical challenges in the cycle layouts of S-CO2 and its specific thermal integration with coal-fired heat resources. This paper provides a detailed review of the research progress on the coal-fired power generation using S-CO2 Brayton cycles. The basic knowledge of S-CO2 properties, the promising S-CO2 power cycles and the conceptual designs for S-CO2 coal-fired power plants are comprehensively summarized, with some key issues in the constructing process and the corresponding engineering solutions being emphatically discussed. Based on the current achievements, the overall technical and economic evaluations on the S-CO2 coal-fired power system are figured out. Furthermore, the specific integration applications of S-CO2 cycles with different coal firing devices and modes including pulverized coal combustion, circulating fluidized bed combustion, oxy-coal combustion, pressurized fluidized bed combustion, chemical looping combustion are discussed. Finally, the main challenges requiring further studies are highlighted.

This paper discusses the efforts to shrink the micro-bump pitch to $20\ \mu\mathrm{m}$ and then $10\ \mu\mathrm{m}$ with solder micro-bumps for silicon-on-silicon 3D assembly by leveraging alternate solder diffusion barrier metals and tuning the assembly process to realize both good yield and reliable interconnects. Specifically in this paper, the assembly process challenges are detailed and the impact of our barrier metal assessment and process optimization to resolve these technical challenges are discussed through the study of solder joint reliability results using internal $20 \mu \mathrm{m}$ pitch and $10\ \mu\mathrm{m}$ pitch solder micro-bump test-vehicles (TV).

// Qianqian Hou 1, * , Fei Liao 1, * , Shouyue Zhang 1, * , Duyu Zhang 1, * , Yan Zhang 2 , Xueyan Zhou 1 , Xuyang Xia 1 , Yuanxin Ye 8 , Hanshuo Yang 3 , Zhaozhi Li 1 , Leiming Wang 4 , Xi Wang 5 , Zhigui Ma 6 , Yiping Zhu 6 , Liang Ouyang 3 , Yuelan Wang 1 , Hui Zhang 7 , Li Yang 3 , Heng Xu 1, 8 , Yang Shu 1 1 Department of Laboratory Medicine, Precision Medicine Center, State Key Laboratory of Biotherapy and Precision Medicine Key Laboratory of Sichuan Province, West China Hospital, Sichuan University and Collaborative Innovation Center, Chengdu, Sichuan, China 2 Department of Thoracic Oncology, Cancer Center, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China 3 State Key Laboratory of Biotherapy, West China Hospital, Sichuan University and Collaborative Innovation Center, Chengdu, Sichuan, China 4 Department of Molecular Biology, Baylor College of Medicine, Houston, Texas, USA 5 Department of Microbiology, Immunology and Molecular Genetics, University of California at Los Angles, Los Angles, California, USA 6 Department of Pediatric Hematology/Oncology, West China Second Hospital, Sichuan University, Chengdu, Sichuan, China 7 Department of Pharmaceutical Sciences, St. Jude Children’s Research Hospital, Memphis, TN, USA 8 Department of Laboratory Medicine, Research Center of Clinical Laboratory Medicine, West China Hospital, Sichuan University, Chengdu, Sichuan, China * These authors contributed equally to this work Correspondence to: Heng Xu, email: xuheng81916@scu.edu.cn Yang Shu, email: shuyang1986@gmail.com Keywords: GATA3, acute lymphoblastic leukemia, tissue-specific regulation network, microarray datasets Received: February 21, 2017 Accepted: March 11, 2017 Published: March 21, 2017 ABSTRACT GATA3 polymorphisms were reported to be significantly associated with susceptibility of pediatric B-lineage acute lymphoblastic leukemia (ALL), by impacting on GATA3 expression. We noticed that ALL-related GATA3 polymorphism located around in the tissue-specific enhancer, and significantly associated with GATA3 expression. Although the regulatory network of GATA3 has been well reported in T cells, the functional status of GATA3 is poorly understood in B-ALL. We thus conducted genome-wide gene expression association analyses to reveal expression associated genes and pathways in nine independent B-ALL patient cohorts. In B-ALL patients, 173 candidates were identified to be significantly associated with GATA3 expression, including some reported GATA3 -related genes (e.g., ITM2A ) and well-known tumor-related genes (e.g., STAT4 ). Some of the candidates exhibit tissue-specific and subtype-specific association with GATA3 . Through overexpression and down-regulation of GATA3 in leukemia cell lines, several reported and novel GATA3 regulated genes were validated. Moreover, association of GATA3 expression and its targets can be impacted by SNPs (e.g., rs4894953), which locate in the potential GATA3 binding motif. Our findings suggest that GATA3 may be involved in multiple tumor-related pathways (e.g., STAT/JAK pathway) in B-ALL to impact leukemogenesis through epigenetic regulation.

DNA methylation plays a significant role in many diseases. Age-related macular degeneration (AMD) is a leading cause of vision loss for people aged 50 years and above, but the etiology and pathogenesis are largely unknown. This study aimed to identify the aberrantly methylated differentially expressed genes (DEGs) in AMD and predict the related pathways on the basis of public data. Aberrant methylation can influence the functions of key genes by altering their expression. Here, we found out DEGs by overlapping public microarray data (GSE29801 and GSE102952). Functional and enrichment analyses of selected genes were performed using the DAVID database. Subsequently, protein–protein interaction (PPI) networks were constructed by using STRING and visualized in cytoscape to determine hub genes. Finally, we collected AMD patients’ blood samples to identify the methylation statuses of these hub genes by using methylated DNA immunoprecipitation. In total, 156 hypermethylation-low expression genes and 127 hypomethylation-high expression genes were predicted. The hypermethylation-low expression genes were enriched in biological processes of response to cardiac conduction, ATP binding, and cell–cell junction assembly. The top 5 hub genes of the PPI network were HSP90AA1, HSPA1L, HSPE1, HSP90B1, and NOP56. Meanwhile, the hypomethylation-high expression genes were enriched in the biological processes of response to positive regulation of the MAPK cascade, actin cytoskeleton reorganization, dentate gyrus development, and cell migration. The top 5 hub genes of this PPI network were PIK3R1, EZR, IGF2, SLC2A1, and CDKN1C. Moreover, the methylation statuses of NOP56, EZR, IGF2, SLC2A1, CDKN1C were confirmed to be altered in the blood of AMD patients. This study indicated possible aberrantly methylated DEGs and differentially expressed pathways in AMD by bioinformatics analysis, providing novel insights for unraveling the pathogenesis of AMD. Hub genes, including NOP56, EZR, IGF2, SLC2A1, CDKN1C, might serve as aberrant methylation-based candidate biomarkers for AMD in future applications.

The industry has witnessed the adoption of the flip chip for its low cost, small form factor, high performance, and great I/O flexibility. As three-dimensional (3D) packaging technology moves to the forefront, the flip chip to wafer integration, which is also a silicon-to-silicon assembly, is gaining more and more popularity. No flow underfill is of special interest for the wafer level flip chip assembly, as it can dramatically reduce the process time and the cost per package, due to the reduction in the number of process steps as well as the dispenser and cure oven that would otherwise be necessary for the standard capillary underfill process. This paper introduces the development of a no flow underfill process for a sub-100 micron pitch flip chip to CSP wafer level assembly. Challenges addressed include the no flow underfill reflow profile study, underfill dispense amount study, chip floating control, underfill voiding reduction, and yield improvement. Also, different no flow underfill candidates were investigated to determine the best performing processing material.

The industry has witnessed the adoption of flip chip for its low cost, small form factor, high performance and great I/O flexibility. As the Three Dimensional (3D) packaging technology moves to the forefront, the flip chip to wafer integration, which is also a silicon to silicon assembly, is gaining more and more popularity. Most flip chip packages require underfill to overcome the CTE mismatch between the die and substrate. Although the flip chip to wafer assembly is a silicon to silicon integration, the underfill is necessary to overcome the Z-axis thermal expansion as well as the mechanical impact stresses that occur during shipping and handling. No flow underfill is of special interest for the wafer level flip chip assembly as it can dramatically reduce the process time as well as bring down the average package cost since there is a reduction in the number of process steps and the dispenser and cure oven that would be necessary for the standard capillary underfill process. Chip floating and underfill outgassing are the most problematic issues that are associated with no flow underfill applications. The chip floating is normally associated with the size/thickness of the die and volume of the underfill dispensed. The outgassing of the no flow underfill is often induced by the reflow profile used to form the solder joint. In this paper, both issues will be addressed. A very thin, fine pitch flip chip and 2x2 Wafer Level CSP tiles are used to mimic the assembly process at the wafer level. A chip floating model will be developed in this application to understand the chip floating mechanism and define the optimal no flow underfill volume needed for the process. Different reflow profiles will be studied to reduce the underfill voiding as well as improve the processing yield. The no flow assembly process developed in this paper will help the industry understand better the chip floating and voiding issues regarding the no flow underfill applications. A stable, high yield, fine pitch flip chip no flow underfill assembly process that will be developed will be a very promising wafer level assembly technique in terms of reducing the assembly cost and improving the throughput.

The hydrothermal treatment (HT) is an effective method to remove chlorine from chlorinated wastes under mild conditions. However, the alkali was required to improve the dechlorination efficiency. Meanwhile, the alkalis contents removed was necessary to realize the clean and highly efficient utilization of coal. This work was trying to investigate the feasibility of simultaneously removal alkalis and chlorine by co-hydrothermal treatment of PVC and high-alkali coal. The effect of operating conditions including the HT temperature, the holding time and particle sizes of coal on the dechlorination efficiency (DE) of PVC during the HT process was experimentally studied in this work. The results show that the DE increased with the rise of: 1) particle sizes (0.054~0.22mm), 2) holding time (30~90 min) and 3) temperature (240~300 °C). In detail, under 300 °C and 60min of holding time, the 85.18% of DE with first PS was lower than the 93.93% of DE with second PS and 100% of DE with third PS. The organic chlorine mainly transferred into chloridion in aqueous solution in HT process. All the results indicate that it is a prospective way to simultaneously removal alkalis and chlorine by co-hydrothermal treatment of chlorinated wastes and high-alkali coal.

Market demand is increasing for even higher packaging densities, smaller size, lower cost, and more heterogeneous functionality. As a result, three dimensional (3D) packaging has emerged as a leading packaging solution. This paper introduces a 3D Wafer Level CSP packaging architecture that provides a cost effective, rapid time to market alternative to emerging 3D die to wafer integration technologies.