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Space flight produces an extreme environment with unique stressors, but little is known about how our body responds to these stresses. While there are many intractable limitations for in-flight space research, some can be overcome by utilizing gene knockout-disease model mice. Here, we report how deletion of Nrf2, a master regulator of stress defense pathways, affects the health of mice transported for a stay in the International Space Station (ISS). After 31 days in the ISS, all flight mice returned safely to Earth. Transcriptome and metabolome analyses revealed that the stresses of space travel evoked ageing-like changes of plasma metabolites and activated the Nrf2 signaling pathway. Especially, Nrf2 was found to be important for maintaining homeostasis of white adipose tissues. This study opens approaches for future space research utilizing murine gene knockout-disease models, and provides insights into mitigating space-induced stresses that limit the further exploration of space by humans., Using Nrf2 knockout mice, Suzuki, Uruno, Yumoto et al. show that space travel activates Nrf2 signaling, which contributes to the weight gain of mice by regulating fat metabolism of white adipose tissues. This study provides insights into potential interventions to mitigate stresses that accompany space travels.

IL-17A is a proinflammatory cytokine produced by many types of innate immune cells and Th17 cells and is involved in the elimination of extracellularly growing microorganisms, yet the role of this cytokine in the host defense against intracellularly growing microorganisms is not well known. Cryptococcus deneoformans is an opportunistic intracellular growth fungal pathogen that frequently causes fatal meningoencephalitis in patients with impaired immune responses. In the current study, we analyzed the role of IL-17A in the host defense against C. deneoformans infection. IL-17A was quickly produced by γδT cells at an innate immune phase in infected lungs. In IL-17A gene–disrupted mice, clearance of this fungal pathogen and the host immune response mediated by Th1 cells were significantly accelerated in infected lungs compared with wild-type mice. Similarly, killing of this fungus and production of inducible NO synthase and TNF-α were significantly enhanced in IL-17A gene–disrupted mice. In addition, elimination of this fungal pathogen, Th1 response, and expression of IL-12Rβ2 and IFN-γ in NK and NKT cells were significantly suppressed by treatment with rIL-17A. The production of IL-12p40 and TNF-α from bone marrow–derived dendritic cells stimulated with C. deneoformans was significantly suppressed by rIL-17A. In addition, rIL-17A attenuated Th1 cell differentiation in splenocytes from transgenic mice highly expressing TCR for mannoprotein 98, a cryptococcal Ag, upon stimulation with recombinant mannoprotein 98. These data suggest that IL-17A may be involved in the negative regulation of the local host defense against C. deneoformans infection through suppression of the Th1 response.

Summary: The Keap1-Nrf2 system plays a central role in the oxidative stress response; however, the identity of the reactive oxygen species sensor within Keap1 remains poorly understood. Here, we show that a Keap1 mutant lacking 11 cysteine residues retains the ability to target Nrf2 for degradation, but it is unable to respond to cysteine-reactive Nrf2 inducers. Of the 11 mutated cysteine residues, we find that 4 (Cys226/613/622/624) are important for sensing hydrogen peroxide. Our analyses of multiple mutant mice lines, complemented by MEFs expressing a series of Keap1 mutants, reveal that Keap1 uses the cysteine residues redundantly to set up an elaborate fail-safe mechanism in which specific combinations of these four cysteine residues can form a disulfide bond to sense hydrogen peroxide. This sensing mechanism is distinct from that used for electrophilic Nrf2 inducers, demonstrating that Keap1 is equipped with multiple cysteine-based sensors to detect various endogenous and exogenous stresses. : The Keap1-Nrf2 system plays a central role in the oxidative stress response. Suzuki et al. show that the H2O2 sensor of Keap1 is distinct from those used for electrophilic inducers. Keap1 exploits Cys226, Cys613, and Cys622/624 residues for sensing H2O2, and these residues set up an elaborate fail-safe mechanism. Keywords: Keap1, Nrf2, reactive cysteine residues, oxidative stress response

Heterogeneous Integration is evolving to acquire finer resolution and larger devices to leverage the advantages provided by More-than-Moore manufacturing and packaging technologies that can help maximize the efficiency and increase the bandwidth of high performance computing systems. Advanced Packaging with submicron Redistribution Layers (RDL) and large package sizes is one of solutions that can help enable complex Heterogeneous Integration designs for applications including Artificial Intelligence (AI), 5G communication and autonomous driving. For systems requiring large package sizes, Panel Level Packaging (PLP) can offer efficiency and cost advantages over Wafer Level Packaging (WLP). PLP however poses unique technical challenges including the requirement to realize uniform submicron patterning across the entire rectangular panel. To meet this challenge, Canon developed the first patterning exposure tool or stepper that is capable of submicron resolution on 500 mm panels. This new panel exposure tool is equipped with wide-field projection optics that offer a large $\mathrm{52}\ \text{mm}\times \mathrm{68}\ \text{mm}$ image field and 0.24 NA that is optimum for submicron resolution. The stepper also features a newly developed panel handling system for processing up to $\mathrm{515}\times \mathrm{515}\ \text{mm}$ panels. In this paper, we will report on evaluation results of fine patterning for a mass-production panel level packaging process using the new submicron resolution panel stepper. We will also discuss current fine-PLP status, challenges and solutions. One topic of our study is patterning uniformity. In 2020, we reported patterning uniformity improvement technology using a glass substrate. This study attempts to apply the technology described in 2020 to improve pattern uniformity on Copper Clad Laminate (CCL) substrates that are widely used in printed circuit board (PCB) manufacturing. In addition, we will report on results of studies of stitching capability and alignment accuracy on substrates with die placement error. Our study also explored warped panel handling including the development of a multi-vacuum line chucking system.

More-than-Moore approaches to improve system performance have been a hot topic for a more than a decade as a way to maximize the efficiency and increase the bandwidth of high performance computing systems. Fan-Out packaging that realizes submicron Redistribution Lines (RDL) and large die sizes is one technology that can help enable complex heterogeneous integration for applications including Artificial Intelligence (AI) and autonomous driving. For systems requiring large package sizes, Panel Level Packaging (PLP) can offer efficiency and cost advantages over Wafer Level Packaging (WLP). PLP however poses unique technical challenges including the requirement to realize uniform submicron patterning across the entire rectangular panel. To meet this challenge, Canon developed the first patterning exposure tool (stepper) capable of submicron resolution on 500 mm panels. The panel exposure tool is equipped with wide-field projection optics that offer a large 52 mm × 68 mm image field and a 0.24 NA that is optimum for submicron resolution. The stepper also features an updated panel handling system for processing up to 515 × 515 mm panels. In this paper, we will report on our study of fine patterning on rectangular panels using the submicron resolution panel stepper and will introduce technology innovations supporting advanced heterogeneous integration. Our study researched photoresist material performance and slit-coating uniformity challenges we identified through collaboration with resist vendors and slit-coating equipment manufacturers. We will report on the results of our collaborative study and will discuss current and future PLP advantages, challenges and solutions.

High-Performance Computing (HPC) systems increasingly adopt Heterogeneous Integration (HI) technologies that utilize large substrates and high-resolution processes to facilitate die and chiplet. Fan-Out Wafer Level Packaging (FOWLP) and silicon interposers using high-density Redistribution Layers (RDL) can help maximize bandwidth and performance but HI roadmaps require improvements in resolution and lower costs to enable wide adoption of these More-than-Moore technologies. Panel based processes can provide cost advantages compared to wafer processes for fabrication of large interposers and Fan-Out packages. Panel based SiP processes however demand submicron resolution over a large field size and uniform exposure across large panels. To meet these challenges, Canon developed the first lithography exposure system capable of achieving submicron resolution on large panels. The new panel exposure tool targets 0.8 μm design rules and utilizes a new panel handling system and stage that allows processing of panels as large as 515 × 515 mm. The new panel exposure tool is equipped with a UL82 wide-field projection lens with a maximum Numerical Aperture (NA) of 0.24 and offers a 52 × 68 mm exposure field for large device fabrication without stitching adjacent shots. Fine-RDL lithography systems must provide a large Depth-of-Focus (DoF) to maintain pattern fidelity to maximize DoF, the new panel exposure tool applies die-by-die focus and tilt compensation and functions to compensate for panel warpage. Process factors related to DoF include panel flatness and photoresist materials and film uniformity. This paper details test results from a panel exposure system that confirms the feasibility and advantages of submicron panel processes. We also introduce additional challenges related to panel processes including slit-coater uniformity, photo resist materials and panel flatness. We will present data illustrating that new panel exposure tool can provide excellent resolution across large exposure fields on panels to enable HI innovation.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

More-than-Moore approaches to improving system performance have been a hot topic for a decade, starting with 3D-integration using Through-Silicon Vias (TSV) and silicon interposers. Today, Heterogeneous Integration (HI) technologies including Fan-Out Wafer-Level Packaging (FOWLP) with fine Redistribution Layers (RDL) are promising technologies that can deliver benefits not possible with More-Moore scaling alone.Fan-Out devices are required to meet the demands of advanced Graphics Processing Unit (GPU) and Field-Programmable Gate Arrays (FPGA) that require wideband interconnection with memory for Artificial Intelligence (AI) and autonomous driving. Next-generation devices require submicron RDL and large die sizes to enable high-performance computing using GPU and FPGA designs.For large die-size devices, Fan-out Panel Level Packaging (FOPLP) can offer efficiency and cost advantages compared to FOWLP, however FOPLP poses unique technical challenges including the requirement to realize uniform submicron patterning across the entire rectangular panel. To meet this challenge, Canon developed the first 500 mm panel size patterning exposure tool capable of submicron resolution.The new panel exposure tool is equipped with a wide-field projection optics that offer a wide image field (52 mm x 68 mm) and optimum 0.24 NA for sub-micron resolution and a newly developed panel handling system that handles up to 515 mm x 515 mm panels.Die-by-die focus and tilt compensation are necessary to realize submicron patterning and Canon’s panel exposure tools adopt a front-end i-line stepper, on-axis optical focus, tilt system for die-by-die focus and tilt measurement. Canon also developed a new panel stage that executes die-by-die focus and tilt compensation.Canon manufactured a debug tool and confirmed the new panel exposure tool advantages for submicron FOPLP high volume manufacturing and in this paper, we will report on the performance of the new submicron patterning panel exposure tool and will introduce technology innovations supporting advanced heterogeneous integration technologies. We will also discuss current and future FOPLP advantages and challenges and will report on FOPLP resolution performance related to slit coater performance, photoresist materials and the flatness of panel substrates.

High-Performance Computing systems can employ leading-edge Heterogeneous Integration (HI) technology including Fan-Out Wafer Level Packaging (FOWLP) and high-density Redistribution Layers (RDL) to maximize system bandwidth and performance. These More-than-Moore strategies are growing in importance and present unique challenges that must be overcome to enable mainstream adoption. FOWLP roadmaps for interconnections between SoC (System on Chip) and DRAM (Dynamic Random Access Memory), split-die FPGA (Field-Programmable Gate Array) and image sensors and SoC are driving RDL scaling and aggressive FOWLP processes are targeting $0.8\ \mu \mathrm{m}$ design rules. High-resolution lithography is required for high-density, fine-RDL applications and the main lithography challenge is to provide a large Depth-of-Focus (DoF) to reliably pattern sub-micron RDL traces across a large exposure field. This paper details an analysis of candidate optical conditions for sub-micron imaging including data demonstrating the DoF performance of an optimized lithography system (stepper). To meet the high-resolution requirements of fine-RDL processes, Canon developed the FPA-5520iV-HR [20iV-HR] i-line stepper that employs a new projection optical system featuring a maximum 0.24 Numerical Aperture (NA) and a 52 x 34 mm field size. We will present data illustrating that 0.24 NA steppers can provide excellent resolution and pattern fidelity throughout each exposure field across the entire wafer. High-density FOWLP wafers can also display extreme die-shift, warpage and topography that must be addressed to enable high-yield and high-productivity processes. Die placement error in FOWLP wafers creates orders of magnitude more alignment error versus traditional silicon wafers and advanced alignment compensation is required to improve overlay matching. Alignment solutions for processing distorted FOWLP wafers include the Grid-PA system that automatically corrects the wafer loading position based on die-grid sampling, and Enhanced Advanced Global Alignment (EAGA) that allows the stepper to measure and compensate for shift, rotation and intra-field magnification errors on a die-by-die basis. FOWLP reconstituted wafers can also experience large warpage that can decrease productivity and DoF and to combat these challenges, our steppers have been designed to handle wafers with over 5 mm of warpage and are also based on a Front-End-Of-the-Line (FEOL) stepper platform that offers die-by-die tilt and focus measurement and compensation to maximize focus accuracy and DoF. This paper provides an analysis of key lithography challenges facing aggressive FOWLP and fine-RDL processes details of stepper technology that helps enable high-density integration in mass-production. We remain committed to enabling innovation through lithography system performance upgrades and development of original options supporting current and future FOWLP and fine-RDL processes.

In this paper, Canon will report on our most advanced 300 mm i-line stepper, the FPA-5550iZ2. Steppers enjoy an inherent productivity advantage, and Canon has developed solutions that overcome stepper disadvantages to realize an exposure tool with high overlay accuracy and excellent productivity. We will review Canon’s 300 mm i-line steppers evolutions that started in 2001 when our first 300 mm i-line stepper provided only 84 wafer per hour (wph) throughput. In 2018, our latest FPA5550iZ2 has evolved to realize more than 250wph for productivity while maintaining the same base design and almost same footprint. This paper will report the technologies that improve productivity and introduce current and underdevelopment functions that can enhance customer processes.

The Keap1-Nrf2 system plays a central role in the oxidative stress response, however the identity of the reactive oxygen sensor within Keap1 remains poorly understood. Here, we show that a Keap1 mutant lacking eleven cysteine residues retains the ability to target Nrf2 for degradation, but is unable to respond to cysteine-reactive Nrf2 inducers. Of the eleven mutated cysteine residues, we found that four are important for sensing hydrogen peroxide. Our analyses of multiple mutant mice lines, complemented by MEFs expressing a series of Keap1 mutants, revealed that Keap1 utilizes the cysteine residues redundantly to set up an elaborate fail-safe mechanism in which specific combinations of these four cysteine residues can form a disulfide bond to sense hydrogen peroxide. Importantly, this sensing mechanism is distinct from that used for electrophilic Nrf2 inducers, demonstrating that Keap1 is equipped with multiple cysteine-based sensors to detect various endogenous and exogenous stresses.

Lake Fukami-ike is a small eutrophic lake, to improve the water quality of the lake, a lakemanagement project was carried out in 1992. This project involved nutrient diversion and revetmentconstruction along the lake shore. A biotope was built near the lake in 2000. As a result, although the inorganicnitrogen in the lake decreased considerably, chlorophyll-a (phytoplankton) increased slightly. The zooplanktoncommunity in the lake before the project in 1978-1979 predominantly comprised large-sized species (about 1.8mm), however, small-sized species (about 0.1-0.2 mm) were dominant after in 2013-2015. The reason for thedecrease of the large-sized zooplankton was thought to be the possibility of losing habitat space because aquaticmacrophytes of the littoral zone were filled up when revetment construction built in 1992. We compared thebody length and composition of zooplankton community between the lake (nearly emergent plants on the lakeshore) and the biotope (emergent and floating-leaved plant cover). Large-sized zooplankton (about 0.9-1.2mm) were dominant in the biotope, and size distribution did not differ in 1978-1979. The presence of developedaquatic macrophytes was suggested to promote the survival of large zooplankton.

In recent years, demand for high density integration of semiconductor chips has steadily increased due to miniaturization and high-performance requirements of electronics including Smartphones and Tablet PCs. In addition to 3D integration using Through Silicon Via (TSV) technology and 2.5D integration technology using silicon interposers, Fan-Out Wafer Level Packaging (FOWLP) using redistribution processes over chip size has become a hot topic these days.

In recent years, demand for high-density integration of semiconductor chips has steadily increased due to miniaturization and high-performance requirements of electronics including Smartphones and Tablet PCs. In addition to 3D integration using Through-Silicon Via (TSV) technology and 2.5D integration technology using silicon interposers, Fan-Out Wafer Level Packaging (FOWLP) using redistribution processes over chip size has become a hot topic these days. Canon has identified key challenges that must be solved for successful implementation of high-density integration technologies into mass production and to meet these challenges, Canon developed the FPA-5510iV i-line lithography tool which is now widely used at customer sites. In this paper, we will explain details of FPA-5510iV features that support high-density integration, additional challenges that must be solved for successful implementation of high-density integration technologies in mass production and Canon's efforts to solve the remaining challenges.

The Keap1-Nrf2 system plays a central role in cytoprotection against electrophilic/oxidative stresses. Although Cys151, Cys273, and Cys288 of Keap1 are major sensor cysteine residues for detecting these stresses, it has not been technically feasible to evaluate the functionality of Cys273 or Cys288, since Keap1 mutants that harbor substitutions in these residues and maintain the ability to repress Nrf2 accumulation do not exist. To overcome this problem, we systematically introduced amino acid substitutions into Cys273/Cys288 and finally identified Cys273Trp and Cys288Glu mutations that do not affect Keap1's ability to repress Nrf2 accumulation. Utilizing these Keap1 mutants, we generated stable murine embryonic fibroblast (MEF) cell lines and knock-in mouse lines. Our analyses with the MEFs and peritoneal macrophages from the knock-in mice revealed that three major cysteine residues, Cys151, Cys273, and Cys288, individually and/or redundantly act as sensors. Based on the functional necessity of these three cysteine residues, we categorized chemical inducers of Nrf2 into four classes. Class I and II utilizes Cys151 and Cys288, respectively, while class III requires all three residues (Cys151/Cys273/Cys288), while class IV inducers function independently of all three of these cysteine residues. This study thus demonstrates that Keap1 utilizes multiple cysteine residues specifically and/or collaboratively as sensors for the detection of a wide range of environmental stresses.

Lake Fukami-ike is a small monomictic and eutrophic lake, located in southern Nagano Prefecture in Central Japan. An uncommon phenomenon of dissolved oxygen 0-1 mgL -1 from the surface to the bottom layer occurred on 16 November, 2013. On November 2, Trichocerca similis (Rotatoria) etc. dominantly distributed from 0-5 m depth depending on distribution DO concentration. Tintinnopsis lacustris (Protozoa) was found in the bottom layer (anoxic condition). The number of cells (Fragilaria rumpens (Bacillariophyceae) etc. abounded from the 0-5 m layer. On November 16, T. lacustris distributed from the surface to the bottom layer. Then, T. lacustris continued to distribute from the surface to the bottom layer, and the genus Synedra was found to have distributed uniformly from the surface to 6 m depth in the next investigation on 21 December, when the DO concentration was about 10 mgL -1 from the surface to the bottom layer. The changes in vertical distribution of T. lacustris, seemed to indicate that lake water was lifted from the bottom layer when shift stagnation periods to circulation periods.

Lake Fukami-ike is a small monomictic and eutrophic lake, located in southern NaganoPrefecture in central Japan. Water quality improvement was expected from maintenance of farm villagedrainage and waterfront function was carried out for town activation in 1992. However, no blue-green algalbloom outbreak had occurred before. We studied the water quality and compositions of the zooplankton andphytoplankton before and after building a bulkhead maintenance construction. Large decreased values forNO3-N, NH4-N and NO2-N were 1.87→0.50 gNm-2(26.7%), 1.49→0.78 gNm-2(52.3%) and 0.085→0.030gNm-2(35.3%), respectively. Aphanizomenon flos-aquae (Cyanophyceae) were dominant in the summer;some species of the genus Fragilaria were dominant among phytoplankton during study periods. Thedominant species of zooplankton during study periods were Keratella cochlearis (Rotatoria); smaller thanCyclops vicinus (Crustaceae) were dominant species of zooplankton before the construction.

Self-assembled monolayers (SAMs) of glucose derivatives on gold have been prepared from alpha- and beta-glucopyranosylamide derivatives. The glucosyl conjugates were synthesized stereoselectively via the in situ generation of glucosyl isoxazolines followed by treatment with thiopyridyl esters. The resulting film structures were characterized by atomic force microscopy, reflection Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy. The experimental data indicated that alpha- or beta-linked glucopyranosylamide derivatives with free hydroxyl groups attach to gold via the thiol linker. Both derivatives form monolayer films with high packing densities--comparable to those typically observed for alkanethiol monolayers on gold. Acetate analogues of these conjugates do not form SAMs on gold; they form multilayered films under identical deposition conditions.

In recent years, demand for high-density integration of semiconductor chips has steadily increased due to miniaturization and high-performance requirements of electronics including Smartphones and Tablet PCs. In addition to 3D integration using Through-Silicon Via (TSV) technology, 2.5D integration technology using silicon interposers has also become a hot topic. Canon has identified key challenges that must be solved for successful implementation of high-density integration technologies into mass production and to meet these challenges, Canon developed the FPA-5510iV i-line lithography tool (stepper) that is now in wide use at customer sites for their most challenging processes. In this paper, Canon will explain details of FPA-5510iV features that support high-density integration. Canon will also introduce additional challenges that must be solved to ensure the success of high-density integration technologies in mass production, as well as Canon efforts to solve the remaining challenges.

A previously proposed double sinusoidal phase-modulating (DSPM) laser-diode interferometer measures distances larger than a half-wavelength by detecting modulation depth. Although it requires a vibrating mirror to provide the second modulation to the interference signal, such vibrations naturally affect measurement accuracy. We propose a static-type DSPM laser-diode interferometer that uses no mechanical modulation. Our experimental results indicate a measurement error of +/- 1.6 microm.