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Department of Energy Engineering (Battery Science and Technology)Anode???free seawater batteries have emerged as a prospective candidate for next-generation energy-storage cells because of their unique discharge and charge characteristics. To fulfill this promise, reliable Na metal plating on the current collector surface is an important requirement for improving electrochemical properties. Here, we develop a strategy for deterministic growth of Na metal on a pre-patterned current collector. The different surface energies of the Cu and Al metal surfaces enable the growth of patterned Na islands during electrochemical deposition, which efficiently form a film-like layer of Na metal. In particular, determining an optimum ratio between the metal-pattern diameter and the distance between adjacent pattern edges is the critical factor for producing decent Na metal pattern array that can facilitate the enhancement of Coulombic efficiency and cycling capability of a half-cell structure. Moreover, patterned growth of Na metal is highly beneficial to enhancement of the electrochemical performance of seawater batteries. By using a Na super-ionic conductor separator with a Cu/Al pre-patterned current collector, well-patterned growth of Na islands with improved cycling stability for over 200 cycles can be obtained for anode???free seawater battery.clos

Two Essays on Local Government Finances in the United States

County governments in the United States play important roles in the tax collection and public service provisions. Thus, a better understanding of the local government finances is closely related to the welfares of residents. In this dissertation, I provide two essays: in the first essay, I examine the fiscal impacts of multiple hurricanes on the county government tax revenues, and in the second essay, I examine the potential correlation between the institutional characteristics of county governments and the spatially varying expenditure determination processes. The two essays contribute to current local government finance literature in the United States. In the first essay, I investigate the fiscal impact of multiple hurricanes on county government tax revenues and the potential adaptation effect. I compare the changes in tax revenues before and after the multiple hurricane incidences to identify the fiscal impact of multiple hurricanes and the potential adaptation effect. I use the tax revenue data in the year 2002 and 2007. I define the years between 2003 and 2006 as the treatment period and I count the number of hurricanes each county experiences. Then, I divide the counties into two groups: if the number of hurricanes in a county during the treatment period is more than 1, I call it “Treatment”, and otherwise, I call it “Control”. I call the year before the treatment period, 2002, as the pre-treatment year and I call the year after the treatment period, 2007, as the post-treatment year. I find that the share of property tax in Treatment increases, mainly due to the 45 percent point more decreases in the sales tax of Treatment. However, when I look at the adaptation effect, I see that the share of property tax decreases, partly due to the decrease in the property tax, and partly due to the small decreases in sales tax and taxes on others. In summary, I show that the negative impact of multiple hurricanes on sales tax revenues and the impact is mitigated by the adaptation effects. In the second essay, I provide one mechanism that suggests a potential correlation between the local institutional characteristics and the spatially varying local expenditure determination processes. Based on the microeconomics theory, I present a cost function that suggests the local government’s public service provision expenditure is a function of input price and the level of public service outputs. In the analysis, I use the county governments’ public expenditure data in 2017, count level average wage rate, public health measures, and the employment rates as the public service output variables. I firstly employ one of the spatially varying coefficient estimations (SVCM) approaches to estimate the cost function. The estimation results and the results of the following tests support the claim that there exist spatially varying processes in the cost functions of public service provision. Then, I analyze the correlation between the local institutional characteristics, such as the number of elected county officials and the degree of autonomy of county governments, with spatially varying coefficients of the cost function. The regression results suggest that the institutional characteristics are significantly correlated with the spatially varying coefficients of the cost function. In summary, I present evidence that the disparities in the local institutional characteristics could be one potential cause of the spatially varying processes in the local expenditure determination process

From Opaque to Accountable Governance: Investor Activism for Transparency in Social Media Amid Disruption in Cryptocurrency

Cryptocurrencies have experienced rapid growth, but the absence of regulatory supervision has given rise to concerns regarding transparency. Unlike traditional financial systems, cryptocurrencies lack a central authority, resulting in unclear governance and potential issues. This is exemplified by the problems associated with Initial Coin Offerings (ICOs). The recent crisis at FTX underscores the importance of transparency. While some exchanges are beginning to list assets governed by ethical principles, the path towards establishing accountable governance remains uncertain. Our research delves into how the lack of transparency in cryptocurrency exchanges prompts investors to advocate for accountable governance. We employ an event study approach to examine the impact of the FTX bankruptcy, with a particular focus on activism on Twitter. Our findings indicate that investor demands for transparency encourage exchanges to adopt measures aimed at ensuring accountability, such as conducting Proof of Reserves audits. This shift has the potential to foster a more stable and reliable cryptocurrency ecosystem, ultimately benefiting both investors and the industry as a whole

Analysis of Performance for NAND Flash Based SSDs via Using Host Semantic Information

The use of flash memory based storage devices is rapidly increasing, and user demands for high performance are also constantly increasing. The performance of the flash storage device is greatly influenced by cleaning operations of Flash Translation Layer (FTL). Various studies have been conducted to lower the cost of cleaning operations. However, there are limits to achieve sufficient performance improvement of flash storages without help of a host system, with only limited information in storage devices. Recently, SCSI, eMMC, and UFS standards provide an interface for sending semantic information from a host system to a storage device. In this paper, we analyze effects of semantic information on performance and lifetime of flash storage devices. We evaluate performance and lifetime improvement through SA-FTL (Semantic Aware Flash Translation Layer), which can take advantage of semantic information in storage devices. Experiments show that SA-FTL improves performance and lifetime of flash based storages by up to 30 and 35%, respectively, compared to a simple page-level FTL

Sodium Biphenyl as Anolyte for Sodium-Seawater Batteries

Sodium-based battery systems have recently attracted increasing research interest due to the abundant resources employed. Among various material candidates for the negative electrode, sodium metal provides the highest capacity of theoretically 1165 mAh g(-1) and a very low redox potential of -2.71 versus the standard hydrogen electrode. However, the high reactivity of sodium metal toward the commonly used electrolytes results in severe side reactions, including the evolution of gaseous decomposition products, and, in addition, the risk of dendritic sodium growth, potentially causing a disastrous short circuit of the cell. Herein, the use of sodium biphenyl (Na-BP) as anolyte for the Na-seawater batteries (Na-SWB) is investigated. The catholyte for the open-structured positive electrode is natural seawater with sodium cations dissolved therein. Remarkably, the significant electronic and ionic conductivities of the Na-BP anolyte enable a low overpotential for the sodium deposition upon charge, allowing for high capacity and excellent capacity retention for 80 cycles in full Na-SWB. Additionally, the Na-BP anolyte suppresses gas evolution and dendrite growth by forming a homogeneous surface layer on the metallic negative electrode

TRansPose: Large-Scale Multispectral Dataset for Transparent Object

Transparent objects are encountered frequently in our daily lives, yet recognizing them poses challenges for conventional vision sensors due to their unique material properties, not being well perceived from RGB or depth cameras. Overcoming this limitation, thermal infrared cameras have emerged as a solution, offering improved visibility and shape information for transparent objects. In this paper, we present TRansPose, the first large-scale multispectral dataset that combines stereo RGB-D, thermal infrared (TIR) images, and object poses to promote transparent object research. The dataset includes 99 transparent objects, encompassing 43 household items, 27 recyclable trashes, 29 chemical laboratory equivalents, and 12 non-transparent objects. It comprises a vast collection of 333,819 images and 4,000,056 annotations, providing instance-level segmentation masks, ground-truth poses, and completed depth information. The data was acquired using a FLIR A65 thermal infrared (TIR) camera, two Intel RealSense L515 RGB-D cameras, and a Franka Emika Panda robot manipulator. Spanning 87 sequences, TRansPose covers various challenging real-life scenarios, including objects filled with water, diverse lighting conditions, heavy clutter, non-transparent or translucent containers, objects in plastic bags, and multi-stacked objects. TRansPose dataset can be accessed from the following link: https://sites.google.com/view/transpose-datasetComment: Under revie

PCT-CycleGAN: Paired Complementary Temporal Cycle-Consistent Adversarial Networks for Radar-Based Precipitation Nowcasting

The precipitation nowcasting methods have been elaborated over the centuries because rain has a crucial impact on human life. Not only quantitative precipitation forecast (QPF) models and convolutional long short-term memory (ConvLSTM), but also various sophisticated methods such as the latest MetNet-2 are emerging. In this paper, we propose a paired complementary temporal cycle-consistent adversarial networks (PCT-CycleGAN) for radar-based precipitation nowcasting, inspired by cycle-consistent adversarial networks (CycleGAN), which shows strong performance in image-to-image translation. PCT-CycleGAN generates temporal causality using two generator networks with forward and backward temporal dynamics in paired complementary cycles. Each generator network learns a huge number of one-to-one mappings about time-dependent radar-based precipitation data to approximate a mapping function representing the temporal dynamics in each direction. To create robust temporal causality between paired complementary cycles, novel connection loss is proposed. And torrential loss to cover exceptional heavy rain events is also proposed. The generator network learning forward temporal dynamics in PCT-CycleGAN generates radar-based precipitation data 10 minutes from the current time. Also, it provides a reliable prediction of up to 2 hours with iterative forecasting. The superiority of PCT-CycleGAN is demonstrated through qualitative and quantitative comparisons with several previous methods.Comment: CIKM 202

NIH3T3 Directs Memory-Fated CTL Programming and Represses High Expression of PD-1 on Antitumor CTLs

Memory CD8+ T cells have long been considered a promising population for adoptive cell therapy (ACT) due to their long-term persistence and robust re-stimulatory response. NIH3T3 is an immortalized mouse embryonic fibroblast cell line. We report that NIH3T3-conditioned medium (CM) can augment effector functions of CTLs following antigen priming and confer phenotypic and transcriptional properties of central memory cells. After NIH3T3-CM-educated CTLs were infused into naïve mice, they predominantly developed to central memory cells. A large number of NIH3T3-CM-educated CTLs with high functionality persisted and infiltrated to tumor mass. In addition, NIH3T3-CM inhibited CTLs expression of PD-1 in vitro and repressed their high expression of PD-1 in tumor microenvironment after adoptive transfer. Consequently, established tumor models showed that infusion of NIH3T3-CM-educated CTLs dramatically improved CTL mediated-antitumor immunity. Furthermore, NIH3T3-CM also promoted human CD8+ T cells differentiation into memory cells. These results suggest that NIH3T3-CM-programmed CTLs are good candidates for adoptive transfer in tumor therapy

Association between serum klotho levels and cardiovascular disease risk factors in older adults

Abstract Background Klotho deficiency is a significant predictor of cardiovascular disease (CVD)-related mortality and morbidity. However, research assessing the association between klotho and individual risk factors of CVD is limited. This study aimed to explore the association between circulating serum klotho levels and risk factors for CVD in adults. Methods We used the 2007–2016 National Health and Nutrition Examination Survey and included 13,154 participants for whom serum klotho levels were available. Body mass index (BMI), exercise, smoking status, alcohol consumption, hypertension, dyslipidemia, serum lipid parameters, and blood pressure were considered as CVD risk factors. Results Circulating klotho levels were negatively associated with being overweight (beta coefficient: − 22.609, p = 0.0025), obesity (beta coefficient: − 23.716, p = 0.0011), current smoking (beta coefficient: − 46.412, p < 0.0001), and alcohol consumption (beta coefficient: − 51.194, p < 0.0001). There was a positive association between serum klotho levels and no history of dyslipidemia (beta coefficient: 15.474, p = 0.0053). Serum klotho levels were significantly decreased by a unit increase in triglycerides (beta coefficient: − 0.117, p = 0.0006) and total cholesterol (beta coefficient: − 0.249, p = 0.0002). There was a significant non-linear relationship between serum klotho levels, triglycerides, and total cholesterol. Conclusions Lower serum klotho levels are associated with certain CVD risk factors, including high BMI, smoking, alcohol consumption, and lipid parameters (triglycerides and total cholesterol). This study suggests that the soluble klotho level may be a potential marker for CVD risk