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    Electrolyte engineering for highly inorganic solid electrolyte interphase in high-performance lithium metal batteries

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    Electrolytes play pivotal roles in the stabilization of Li metal surface and operation at high voltages. In particular, localized high-concentration electrolytes have outperformed state-of-the-art electrolytes due to their unique solvation structures. However, a direct correlation between solvation structure in LHCEs, in particular for weakly coordinated diluents, and SEI composition is not well understood, yet it is highly critical to realize high Coulombic efficiency (CE) beyond 99.5%. Here, a class of electrolyte based on bis(2,2,2-trifluoroethoxy)methane and 1,2-dimethoxyethane was introduced to regulate anion decomposition to achieve ultra-high Li2O content of 63% in the SEI along with a highly uniform phase distribution. These unique features enabled a record-high CE of 99.72% and proved the impact of homogeneously distributed high Li2O SEI. The related Li|LiNi0.8Co0.1Mn0.1O2 full cell with a negative/positive capacity ratio of 2.5 achieved 90% capacity retention after 200 cycles at 1 C and 80% retention after 596 cycles at 3 C.N

    Childrens English Novels Lexically Appropriate for Korean Elementary School Students : A Corpus-Based Study

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    This study aimed to determine the number of word types that Korean elementary school students should know in order to comprehend English language novels for children. We selected 14 novels that are educationally appropriate for Korean elementary school students and analyzed the word types and tokens in a corpus of the novels. The study assumed that the students knew the 800 elementary-level basic word types in the Korean national curriculum and other comprehensible word types (e.g., loanwords, proper nouns, numbers). We then analyzed the number of word tokens that would be comprehensible to the students. The results showed that 2,613, 3,211, and 4,729 word types covered 90%, 95%, and 98% of the total token frequency, respectively. Of these, 151, 749, and 2,267 word types were found to be incomprehensible to the target students. Based on these results, we discuss suitable lexical sizes for comprehending childrens English novels and the role of teachers in supporting their students while reading these novel

    Effects of Exhaustive Exercise on Inflammatory, Apoptotic, and Antioxidative Signaling Pathways in Human Peripheral Blood Mononuclear Cells

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    In the present study, we investigated the effects of exhaustive exercise and recovery on inflammatory, pro-apoptotic, and antioxidative responses in human peripheral blood mononuclear cells (PBMCs). Sixteen volunteers participated in a guided physical activity program in which they were subjected to progressive exercise on the treadmill until they were exhausted followed by an 1-hour recovery period. Isolated human PBMCs were collected before exercise, immediately after exercise, and after 1-hour recov-ery. Exhaustive exercise induced expression of heme oxygenase-1 and glutamate cysteine ligase catalytic subunit and activation of NF-kappa B and NF-E2 related factor 2 (Nrf2). Apoptosis, as measured by activity and cleavage of caspase-3 and its substrate PARP also significantly increased. However, induction of redox signaling and the pro-apoptotic response fully returned to the baseline level during the 1-hour recovery period. On the other hand, COX-2 expression was continuously elevated after exercise cessation throughout the 1-hour recovery period. Taking all these findings into account, we conclude that exhaustive exercise transiently in-duces Nrf2-mediated antioxidant gene expression and eliminates damaged cells through apoptosis as part of an adaptive cytopro-tective response against oxidative and inflammatory stress.Y

    A Phase II Trial of S-1 and Oxaliplatin in Patients with Metastatic Breast Cancer Previously Treated with Anthracycline and Taxane (KCSG-BR07-03)

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    PURPOSE: This single-arm phase II trial investigate the efficacy and safety of S-1 plus oxaliplatin (SOX) in patients with metastatic breast cancer. Materials and Methods: Patients with metastatic breast cancer previously treated with anthracyclines and taxanes were enrolled. Patients received S-1 (40-60 mg depending on patient's body surface area, twice a day, day 1-14) and oxaliplatin (130 mg/m2, day 1) in 3 weeks cycle until disease progression or unacceptable toxicity. The primary endpoint was objective response rate (ORR) according to Response Evaluation Criteria in Solid Tumor 1.1. Secondary endpoints included time-to-progression (TTP), duration-of-response (DoR), overall survival (OS), and adverse events. RESULTS: A total of 87 patients were enrolled from 11 institutions in Korea. Hormone receptor was positive in 54 (62.1%) patients and six (6.9%) had human epidermal growth factor receptor 2-positive disease. Forty-eight patients (85.1%) had visceral metastasis and 74 (55.2%) had more than three sites of metastases. The ORR of SOX regimen was 38.5% (95% confidence interval [CI], 26.9 to 50.0) with a median TTP of 6.0 months (95% CI, 5.1 to 6.9). Median DoR and OS were 10.3 months (95% CI, 5.5 to 15.1) and 19.4 (95% CI, not estimated) months, respectively. Grade 3 or 4 neutropenia was reported in 28 patients (32.1%) and thrombocytopenia was observed in 23 patients (26.6%). CONCLUSION: This phase II study showed that SOX regimen is a reasonable option in metastatic breast cancer previously treated with anthracyclines and taxanes.Y

    Evaluation of the Antimicrobial Potential and Characterization of Novel T7-Like Erwinia Bacteriophages

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    Simple Summary Erwinia amylovora and E. pyrifoliae cause Erwinia blight, which damage pome fruits, and are highly contagious. We propose the use of bacteriophages to control these two pathogens simultaneously. Many drugs have been used in South Korea for the quick control of blight disease caused by both these species. This can result in antibiotic resistance; hence, phage cocktails have been suggested as an alternative. In this study, we observed that phage cocktails, including four isolated phages, exhibited extensive strain spectra and potential for rapid bacterial control. This study demonstrated the potential of a phage cocktail to replace antibiotics as biocontrol agents against Erwinia blight. The recent outbreak of blight in pome fruit plants has been a major concern as there are two indistinguishable Erwinia species, Erwinia amylovora and E. pyrifoliae, which cause blight in South Korea. Although there is a strict management protocol consisting of antibiotic-based prevention, the area and the number of cases of outbreaks have increased. In this study, we isolated four bacteriophages, pEp_SNUABM_03, 04, 11, and 12, that infect both E. amylovora and E. pyrifoliae and evaluated their potential as antimicrobial agents for administration against Erwinia-originated blight in South Korea. Morphological analysis revealed that all phages had podovirus-like capsids. The phage cocktail showed a broad spectrum of infectivity, infecting 98.91% of E. amylovora and 100% of E. pyrifoliae strains. The antibacterial effect was observed after long-term cocktail treatment against E. amylovora, whereas it was observed for both short- and long-term treatments against E. pyrifoliae. Genomic analysis verified that the phages did not encode harmful genes such as antibiotic resistance or virulence genes. All phages were stable under general orchard conditions. Collectively, we provided basic data on the potential of phages as biocontrol agents that target both E. amylovora and E. pyrifoliae.Y

    Tyrosine-mediated analog resistive switching for artificial neural networks

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    The fourth industrial revolution indispensably brings explosive data processing and storage; thus, a new computing paradigm based on artificial intelligence-enabling device structure is urgently required. Memristors have received considerable attention in this regard because of their ability to process and store data at the same location. However, fundamental problems with abrupt switching characteristics limit their practical application. To address this problem, we utilized the concept of metaplasticity inspired by biosystems and observed gradual switching in the peptide-based memristor at high proton conductivity. An unexpectedly high slope value > 1.7 in the log/-V curve at low voltage (<= 400 mV) was considered the main origin, and it might arise from the modulatory response of proton ions on the threshold of Ag ion migration in the peptide film. With the obtained gradual switching property at high proton conductivity, the device showed significantly increased accuracy of image recognition (similar to 82.5%). We believe that such a demonstration not only contributes to the practical application of neuromorphic devices but also expands the bioinspired functional synthetic platform.N

    Exploring circular water options for a water-stressed city: Water metabolism analysis for Paju City, South Korea

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    For urban areas with limited water supplies, circular water strategies must be pursued to achieve water security goals. By tracking and balancing all water flows and their potential changes city-wide, urban water metabolism is a useful framework for exploring the effect of circular water strategies on performance. This study focused on a water-stressed city in South Korea, Paju. We first analyzed Paju's current and future water metabolism. We then explored the effects of 10 alternative water management options (implementing four circular water strategies separately or combined, in both conservative and maximum potential cases) on three aspects of water security (water resource efficiency, self-sufficiency, and supply diversification). In 2018, Paju had lower efficiency of water use than our benchmarking case, Seoul, despite Paju's higher level of supply self-sufficiency and diversity. By 2040, the expected growth and increasing water demand of the city would further increase its reliance on water imports, requiring expansion of water infrastructure. However, if Paju employs large-scale wastewater recycling and rainwater harvesting, and reduces its water loss and demand, the combined effect could offset the expected water supply increase between 2018 and 2040, as well as the associated need for additional infrastructure.N

    Examining Racial and Ethnic Disparity in Prosecutor's Bail Requests and Downstream Decision-making

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    Although research into prosecutorial and judicial decision-making has been conducted for the past three decades, a great deal still remains unknown. Most research focuses on the back end of the adjudication process, leaving decision points prior to the final phases unanalyzed. Drawing on unique data from the New York County District Attorneys Office that tracks 43,971 felony complaints, this research explores racial and ethnic disparity at multiple decision points during case processing, with a focus on the prosecutors initial bail request. A combination of regression modeling and path analysis were applied, revealing that the effects of race and ethnicity vary by decision point. Black defendants demonstrated increased bail requests and likelihood of indictment. However, together with Latino defendants, they were less likely to be detained prior to trial compared with White defendants. Despite identifying a mix of positive and negative cumulative effects, we found significant indirect effects of black defendants via bail request that contribute to the unwarranted racial disparities in both pre-trial detention and indictment outcomes. Insights gleaned from this research help prosecutors understand how their initial actions influence final outcomes, as well as contributing to the national conversation on the use of cash bail.Y

    Multi-body dynamics modeling and driving performance evaluation of oil recovery vehicle

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    ยฉ IMechE 2022.In this study, the design and driving performance evaluation of a driving system for driving on deformable terrain was performed using terramechanics theory and multi-body dynamics simulation. For the design of the driving system, the mechanical interaction of track-terrain was analyzed using a Bekker-based model. Based on the analyzed results, the design of a track suitable for the deformable terrain to be driven and selection of a power source (engine, transmission, etc.) were carried out. A multi-body simulation model of the tracked vehicle reflecting the designed track and the selected power source was developed, and a ground model reflecting the mechanical property of terrain was also developed to analyze the mechanical interaction of the track-terrain through simulation. In addition, each link constituting the track was modeled as a 6 DOF spring/damper system to consider the track's tension force and load distribution under the track, and through this, different ground pressure and soil thrust were applied according to the motion state of each link. Finally, driving performance analyses were performed using the developed tracked vehicle, and as a result, it was confirmed that the driving requirements of the tracked vehicle were satisfied.N

    Lithium Metal Batteries: From Fundamental Research to Industrialization

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    Lithium metal batteries (LMBs) are representative of post-lithium-ion batteries with the great promise of increasing the energy density drastically by utilizing the low operating voltage and high specific capacity of metallic lithium. LMBs currently stand at a point of transition at which the accumulation of knowledge from fundamental research is being translated into large-scale commercialization. This review summarizes the available strategies for addressing the intrinsic shortcomings of LMBs, such as the suppression of dendritic growth and parasitic reactions from the material to the electrode to the cell level. The discussion pertaining to the cell level includes efforts and concerns relating to scaling up established knowledge and expertise with the view of commercialization. This article intends to encourage researchers in both fundamental research institutions and industry to make a synergistic effort and share their views comprehensively to ensure that LMB technology continues to evolve in harmony to become a mature technology. This article is protected by copyright. All rights reserved.N


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