293 research outputs found
Comprehensive analysis of microbial communities in full-scale mesophilic and thermophilic anaerobic digesters treating food waste-recycling wastewater
No full textMicrobes were sampled for a year in a full-scale mesophilic anaerobic digester ( MD) and a thermophilic anaerobic digester (TD) treating food waste-recycling wastewater (FRW), then microbial community structure, dynamics and diversity were quantified. In the MD, Fastidiosipila, Petrimonas, vadinBC27, Syntrophomonas, and Proteiniphilum were dominant bacterial genera; they may contribute to hydrolysis and fermentation. In the TD, Defluviitoga, Gelria and Tepidimicrobium were dominant bacteria; they may be responsible for hydrolysis and acid production. In the MD, dominant methanogens changed from Methanobacterium (17.1 +/- 16.9%) to Methanoculleus (67.7 +/- 17.8%) due to the increase in ammonium concentration. In the TD, dominant methanogens changed from Methanoculleus (42.8 +/- 13.6%) to Methanothermobacter (49.6 +/- 11.0%) due to the increase of pH. Bacteria and archaea were more diverse in the MD than in the TD. These results will guide development of microbial management methods to improve the process stability of MD and D treating FRW.11Nsciescopu
Hide-and-seek: Detecting Workers' Emotional Workload in Emotional Labor Contexts Using Multimodal Sensing
No full textEmotional labor refers to the process in which workers are required to express emotions regardless of their actual feelings by the organization. In workplaces where such display rules exist, workers experience an emotional workload. Continued exposure to emotional workload can lead to severe mental and psychological issues. Nevertheless, research on assessing emotional workload remains understudied. In this study, we propose a machine learning model to automatically evaluate workers' emotional workload in emotional labor situations through multimodal sensing. The data collection study was designed based on a call center scenario. Within the study, we manipulated customer behaviors as confederates and assessed the worker's emotional workload. As a result, this study provides a benchmark using well-known features and standard machine learning methods. We achieved an accuracy of up to 87% for binary and three-class classification cases. Finally, we discuss the significance of assessing emotional workload and considerations for its practical application in the workplace.
Microbial communities underpinning mesophilic anaerobic digesters treating food wastewater or sewage sludge: A full-scale study
No full textTen mesophilic full-scale anaerobic digesters treating food wastewater (FW-digesters) or sewage sludge (SL-digesters) were monitored for 1 year to investigate: (1) microbial communities underpinning FW-digesters and SL-digesters, (2) the effects of total ammonia-nitrogen concentration [TAN] and Na+ concentration [Na+] on variations of these communities. [TAN] and [Na+] in the digester varied among digesters: 1.7-6.5 g TAN/L and 1.0-3.6 g Na+/L for the FW-digesters, and 0.1-2.2 g TAN/L and 0.1-1.2 g Na+/L for the SL-digesters; [TAN] negatively correlated with the process efficiency of the FW-digesters. Microbial communities were less diverse in the FW-digesters than in the SL-digesters. The FW- and SL-digesters formed very distinct microbial community structures; [TAN] and [Na+] in the digester were the critical factors shaping these structures. Immigrant bacteria from influent sludge significantly influence the bacterial communities of the SL-digesters. Methanoculleus might be tolerant to high ammonia in AD of such organic wastewater.11Nsciescopu
Designing for separation anxiety: Engaging connection and building trust
No full textDSpace SAF Submission Ingestion Package generated from Vireo submission #17132 on 2022-04-29 at 16:08:58Made available in DSpace on 2022-04-29T21:58:14Z (GMT). No. of bitstreams: 2
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Previous issue date: 2021-12-10Embargo set by: Seth Robbins for item 123408
Lift date: 2024-04-29T21:58:46Z
Reason: Author requested closed access (OA after 2yrs) in Vireo ETD systemAuthor requested closed access (OA after 2yrs) in Vireo ETD systemLimitedSubmission published under a 24 month embargo labeled 'Closed Access', the embargo will last until 2023-12-01The student, Eunji Kim, accepted the attached license on 2021-12-08 at 09:46.The student, Eunji Kim, submitted this Thesis for approval on 2021-12-08 at 09:49.This Thesis was approved for publication on 2021-12-10 at 10:02."""The bird fights its way out of the egg. The egg is the world, and whoever will be born must destroy the world."" - Demian, Hermann Hesse.
As they grow old, babies develop attachment and bonding to their guardians, particularly their mothers. It is a natural human tendency to be excessively reliant on one's parents because they are incapable of surviving without their assistance. In being helped, and their instinctive needs are satisfied, the baby develops attachment and bonding to the guardian who helps them. While an infant develops a connection to a guardian, they may show anxiety and be extra clingy when separation occurs. Many parents and children suffer from these problems, as the parents cannot always be alongside the children. Separation Anxiety Disorder (SAD) could lead to perpetual psychological issues throughout the children's adulthood. Ultimately the goal of a child is to be self-sufficient and independent from their guardian. Along the way, the guardian must be aware of the children's needs and help them cope with the problem.
Within this study, separation anxiety is covered following the infant's cognitive development and how it can be possibly treated. Also, while referencing the traditionally applied or accepted treatment methods, I explored the tangible and intangible design options that could connect children to their parents to soothe their anxiety and help them form a secure attachment to their guardians, and eventually help them be independent.
A human-machine collaborative approach measures economic development using satellite imagery
No full textMachine learning approaches using satellite imagery are providing accessible ways to infer socioeconomic measures without visiting a region. However, many algorithms require integration of ground-truth data, while regional data are scarce or even absent in many countries. Here we present our human-machine collaborative model which predicts grid-level economic development using publicly available satellite imagery and lightweight subjective ranking annotation without any ground data. We applied the model to North Korea and produced fine-grained predictions of economic development for the nation where data is not readily available. Our model suggests substantial development in the country’s capital and areas with state-led development projects in recent years. We showed the broad applicability of our model by examining five of the least developed countries in Asia, covering 400,000 grids. Our method can both yield highly granular economic information on hard-to-visit and low-resource regions and can potentially guide sustainable development programs. © 2023, The Author(s).11Nsciescopu
Two essays in finance
No full textThe student, Eunji Oh, accepted the attached license on 2019-07-03 at 09:31.The student, Eunji Oh, submitted this Dissertation for approval on 2019-07-03 at 09:40.This Dissertation was approved for publication on 2019-07-03 at 13:11.DSpace SAF Submission Ingestion Package generated from Vireo submission #14146 on 2019-11-26 at 13:04:22Made available in DSpace on 2019-11-26T20:49:20Z (GMT). No. of bitstreams: 2
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Previous issue date: 2019-07-03The first essay examines whether systematic equity risk of firms reflects the risk of their R&D strategies at various angles. More novel R&D strategy is risky because it can be related to more extreme outcome. This risk could indirectly affect the firm’s systematic risk. In the case of success of the strategy, the productivity of technologies developed by novel R&D strategy could be procyclical; thus public firms with more novel technologies could be more subject to the aggregate risk. To investigate this problem, I devise an ex-ante measure for the novelty of innovation, Tech Synthesis Level (below TSL), which quantifies the degree that new technology is drawn from prior technologies in the far different technological fields, using patent citations. I find that patents with high TSL are associated with more extreme technological outcomes both at patent-level and startup-level. At public firm analyses, I find that high TSL is associated with high abnormal returns by 2.532 percent (annualized) and high systematic volatility. These findings support the hypothesis that a failure probability of the R&D project increases systematic risk. I also find evidence that high TSL patents are technologically more productive when aggregate innovation is very active, so firms with high TSL patents are subject to high systematic equity risk.
The second essay studies the effect of intangible collateral, which has gradually increased since the ’90s, by testing hypotheses inspired by [Ai et al., 2018]’s collateralizability premium. Firms with more collateralizable capital have lower stock returns due to the insurance effect of the capital during economic recessions when financial constraints get tighter. If intangible collateral also can relax financial constraint, firms with intangible collateral are expected to have lower stock returns than the other similar firms without collateralizable intangible capital. I add empirical evidence by using Dealscan data of US-originated secured long-term loans. I find that firms using intangibles as collateral in addition to traditional collateralizable assets have higher stock returns than the other firms pledging only tangible assets to secure corporate loans. Also, they could achieve the similar or even slightly higher level of leverage, implying intangible collateral also can relax financial constraint. This is not assumed possible in many theoretical and empirical studies. Even with matching analysis I find that firms pledging intangible capital as collateral still have higher stock returns than the other similar firms without intangible collateral. The empirical evidence I find does not fully support the collateralizability premium hypothesis.Submission published under a 24 month embargo labeled 'U of I Access', the embargo will last until 2021-08-01Embargo set by: Seth Robbins for item 112924
Lift date: 2021-11-26T20:49:41Z
Reason: Author requested U of Illinois access only (OA after 2yrs) in Vireo ETD systemU of I Only Restriction Lifted for Item 112924 on 2021-11-27T10:15:30Z
Gaining an operational edge : piece-picking process optimization
No full textThesis: M. Eng. in Logistics, Massachusetts Institute of Technology, Supply Chain Management Program, 2016.Cataloged from PDF version of thesis.Includes bibliographical references (pages 66-67).Order-picking is an integral operation in warehouses and distribution centers (DC), consuming considerable operating resources and expenses. Numerous studies have attempted to optimize the efficiency and reduce the cost of order-picking. In working with a partner company, this thesis evaluates a proposed mechanism for piece-picking that would achieve this end. The company has a shelf-pack number for each SKU, whereby the SKU must be piece-picked in a quantity that is a multiple of the number. The company has proposed to change this number from 1 to 2 to raise the number of units per pick and reduce the number of picks needed for a SKU. In this thesis, simulation is performed on the company's shipment data from DC to store to reveal the merits and demerits of this scheme. SKUs are segmented into different groups based on their suitability for this scheme as a means of mitigating the negative repercussions of the proposal. The scheme can reduce the number of picks and related costs needed, but it causes a shift of inventory from DC to store, thus creating an increase in store inventory. However, SKUs can be allotted into groups suitable or unsuitable for the scheme depending on the amount of savings generated for a given amount of impact on store inventory. The scheme's benefits and impact on store inventory are thoroughly examined, and their implications on DC inventory are also discussed. This thesis offers a novel perspective into piece-picking optimization, and it finds the proposed scheme viable, simple, and flexible.by Stephanie Hsuan-Chia Chen and Eunji Han.M. Eng. in Logistic
Targeting CLK4 inhibits the metastasis and progression of breast cancer by inactivating TGF-beta pathway
No full text© 2021, The Author(s), under exclusive licence to Springer Nature America, Inc.Triple-negative breast cancer (TNBC) represents the most aggressive subtype of breast cancer that is highly resistant to current therapeutic options. According to the public databases Oncomine and KM plotter, the CLK4 expression is correlated with poor patient survival in TNBC, especially in mesenchymal-like TNBC (MES-TNBC) that has strong metastatic potential. Therefore, we investigated the potential involvement of CLK4 in the metastasis and progression of MES-TNBC. In the MES-TNBC cell lines, the CLK4 expression was elevated. Notably, the RNAi-mediated silencing of CLK4 reduced the expression of multiple epithelial-mesenchymal transition (EMT) genes that mediate metastasis. Furthermore, CLK4 silencing reduced both the invasive behaviors of the cultured cells and tumor metastasis in the mouse xenograft model. It is also noteworthy that CLK4 silencing repressed the invasive and cancer stem cell (CSC) properties that are induced by the TGF-β signaling. Importantly, the pharmacological inhibition of CLK4 potently repressed the invasion and proliferation of MES-TNBC cell lines and patient-derived cells, which demonstrates its clinical applicability. Collectively, our results suggest that CLK4 plays a crucial role in invasion and proliferation of MES-TNBC, especially in the processes that are induced by TGF-β. Also, this study characterizes CLK4 as a novel therapeutic target in breast cancer.N
Unveiling degradation mechanisms of anode-free Li-metal batteries
No full textAnode-free Li-metal batteries (AFLMBs), in which Li+ + ions from the cathode are deposited on a Cu substrate and the deposited Li-metal serves as the anode, exhibit higher energy density compared to Li-metal batteries (LMBs). However, achieving stable cycle performance, even at moderate operating conditions, is difficult and has so far hindered their practical uses. In AFLMBs, the homogeneity of solid electrolyte interphase (SEI), initially created by electrolyte reduction on Cu substrate, is not maintained during Li-metal deposition, leading to uncontrolled electrolyte decomposition. The SEI is therefore not conserved, and uneven Li deposition morphology is induced on the Cu substrate and the eventual instability of SEI leads to the overall degradation of AFLMBs. Here, we report on the failure mechanisms of AFLMBs through a comparative study with LMBs using 3 M lithium bis (fluorosulfonyl)imide (LiFSI) dissolved in N,N-dimethylsulfamoyl fluoride. Our investigation reveals that the SEI inhomogeneity in AFLMBs makes Li+ + transport through SEI sluggish and non-uniform, triggering local compositional changes of the initially formed SEI on the Cu substrate and unwanted consumption of FSI-- anion from the electrolyte. This work provides clear understanding to the interfacial engineering and important roles of Li- metal on the Cu substrate in AFLMBs, promising the creation of stable SEI, reversible electrochemical reaction of Li-metal, and interfacial stability of the cathode in LMBs.
ECM 구조 변화를 통한 인간 배아줄기세포 유래 베타 세포 분화 효율 향상
No full text학위논문(박사) - 한국과학기술원 : 생명과학과, 2023.2,[iv, 95 p. :]Pancreatic beta cells derived from human embryonic stem cells (hESCs) are a promising cell source for diabetes treatment. The changes in the extracellular matrix (ECM) control the cell fate of stem cells. Thus, the combination of extracellular signal and intrinsic signaling has been developed as a method to increase differentiation efficiency from hESCs to various lineage. However, attempts to improve the differentiation efficiency into beta cells through modification of the extracellular matrix (ECM) are still insufficient. This study investigated whether the use of Polydimethylsiloxane (PDMS) was advantageous as a substrate to differentiate hESCs into pancreatic endocrine cells. Here, I found that matrigel, an ECM widely used for stem cell culture, was coated in different ways, such as mash or film-like structure on TCPS and PDMS depending on the underlying substrate. Film-like structure of Matrigel coated on PDMS (Matrigel_PDMS) provided higher cellular anchorage between cell-ECM compared to mash-like structure of Matrigel coated on TCPS (Matrigel _TCPS). On the Matrigel_PDMS expression of pancreatic endodermal markers was significantly higher during early pancreatic development of hESCs compared to the Matrigel_TCPS. Furthermore, pancreatic islet-like organoids (PIOs) derived on the Matrigel_PDMS exhibited a higher level of insulin secretion than those on the Matrigel_TCPS. In this study, I confirmed that increment of focal adhesion in hESCs cultured on Matrigel_PDMS during early pancreatic development than those cultured on Matrigel_TCPS. Increased focal adhesion induced activation of YAP/TEF1 in pancreatic endoderm cells, ultimately promoting the transcriptional activities of pancreatic endoderm-associated genes. Interestingly, YAP activation was induced in pancreatic endoderm cells via the integrin α3-FAK-CDC42-PP1A signaling. In this study, I demonstrate that the unique microstructure on Matrigel_PDMS promotes focal adhesions, and then activates YAP via Hippo independent signaling pathway, thereby leading to maturation of pancreatic endocrine development of hESCs in vitro한국과학기술원 :생명과학과
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