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Wastewater‐based surveillance has become an important tool for research groups and public health agencies investigating and monitoring the COVID‐19 pandemic and other public health emergencies including other pathogens and drug abuse. While there is an emerging body of evidence exploring the possibility of predicting COVID‐19 infections from wastewater signals, there remain significant challenges for statistical modeling. Longitudinal observations of viral copies in municipal wastewater can be influenced by noisy datasets and missing values with irregular and sparse samplings. We propose an integrative Bayesian framework to predict daily positive cases from weekly wastewater observations with missing values via functional data analysis techniques. In a unified procedure, the proposed analysis models severe acute respiratory syndrome coronavirus‐2 RNA wastewater signals as a realization of a smooth process with error and combines the smooth process with COVID‐19 cases to evaluate the prediction of positive cases. We demonstrate that the proposed framework can achieve these objectives with high predictive accuracies through simulated and observed real data. [ABSTRACT FROM AUTHOR]

This paper proposes a novel theoretical perspective which views the K-pop industry through the lens of M-ies model. To date, the innovative aspects of K-pop have been largely neglected by business scholarship, in part due to the inadequacies of the existing theories to capture the dynamic nature of its development. To fill this gap, M-ies model is devised. It posits that innovators (i) were critical in creating a sustained level of innovative momentum (M), as they implemented strategies (s) to respond to the external environment (e). Using the M-ies model, we also explain how an intriguing parallel can be drawn between a seemingly unlikely pair, the K-pop and the semiconductor industry. In so doing, we point to the significance of producer-innovators, and how private sector – in particular, SM Entertainment as the first mover – was the main agent of creative destruction. [ABSTRACT FROM AUTHOR]

Despite the role of digital technologies in increasing the popularity of K-pop, little is known about how K-pop entertainment companies digitally transform their business models and the driving forces that shape this transformation. In this study, we present an in-depth case study of a pioneering K-pop entertainment company, SM Entertainment, whose founder's charismatic leadership and organizational capabilities contribute to the digital transformation of its business model through market-pioneering strategies and strategic learning derived from continuous interactions with changing business environments. This transition to the digital business model ultimately leads to sustainable competitive advantages in the marketplace. The important theoretical and practical implications of the findings are discussed. [ABSTRACT FROM AUTHOR]

This study investigates the effect of firm-specific news on the pricing of idiosyncratic volatility (IVOL) in China. Using a sample of non-financial A-share listed firms from January 2006 to June 2018, we find that the predictive ability of IVOL is much weaker around firm announcements compared to that without news, suggesting that the limited arbitrage cannot disentangle the IVOL puzzle completely in the emerging market. Additionally, we investigate the effect of news sentiment on the predictive ability of IVOL and find that it is much stronger following bad news compared to good news. Finally, when we include the macroeconomic variables known to predict returns to adjust the systematic risk, we obtain novel findings that the negative premium of IVOL becomes insignificant, suggesting that the negative premium is time-varying with macroeconomy. [ABSTRACT FROM AUTHOR]

Wastewater‐based SARS‐CoV‐2 surveillance enables unbiased and comprehensive monitoring of defined sewersheds. We performed real‐time monitoring of hospital wastewater that differentiated Delta and Omicron variants within total SARS‐CoV‐2‐RNA, enabling correlation to COVID‐19 cases from three tertiary‐care facilities with >2100 inpatient beds in Calgary, Canada. RNA was extracted from hospital wastewater between August/2021 and January/2022, and SARS‐CoV‐2 quantified using RT‐qPCR. Assays targeting R203M and R203K/G204R established the proportional abundance of Delta and Omicron, respectively. Total and variant‐specific SARS‐CoV‐2 in wastewater was compared to data for variant specific COVID‐19 hospitalizations, hospital‐acquired infections, and outbreaks. Ninety‐six percent (188/196) of wastewater samples were SARS‐CoV‐2 positive. Total SARS‐CoV‐2 RNA levels in wastewater increased in tandem with total prevalent cases (Delta plus Omicron). Variant‐specific assessments showed this increase to be mainly driven by Omicron. Hospital‐acquired cases of COVID‐19 were associated with large spikes in wastewater SARS‐CoV‐2 and levels were significantly increased during outbreaks relative to nonoutbreak periods for total SARS‐CoV2, Delta and Omicron. SARS‐CoV‐2 in hospital wastewater was significantly higher during the Omicron‐wave irrespective of outbreaks. Wastewater‐based monitoring of SARS‐CoV‐2 and its variants represents a novel tool for passive COVID‐19 infection surveillance, case identification, containment, and potentially to mitigate viral spread in hospitals. [ABSTRACT FROM AUTHOR]

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.ydbio.2007.12.025 Byline: Manjong Han (a), Xiaodong Yang (a), Jangwoo Lee (a), Christopher H. Allan (c), Ken Muneoka (a)(b) Keywords: Regeneration; Mammal; Digit; Finger; Blastema; Ossification Abstract: The digit tips of children and rodents are known to regenerate following amputation. The skeletal structure that regenerates is the distal region of the terminal phalangeal bone that is associated with the nail organ. The terminal phalanx forms late in gestation by endochondral ossification and continues to elongate until sexual maturity (8 weeks of age). Postnatal elongation at its distal end occurs by appositional ossification, i.e. direct ossification on the surface of the terminal phalanx, whereas proximal elongation results from an endochondral growth plate. Amputation through the middle of the terminal phalanx regenerates whereas regenerative failure is observed following amputation to remove the distal 2/3 of the bone. Regeneration is characterized by the formation of a blastema of proliferating cells that appear undifferentiated and express Bmp4. Using chondrogenic and osteogenic markers we show that redifferentiation does not occur by endochondral ossification but by the direct ossification of blastema cells that form the rudiment of the digit tip. Once formed the rudiment elongates by appositional ossification in parallel with unamputated control digits. Regenerated digits are consistently shorter than unamputated control digits. Finally, we present a case study of a child who suffered an amputation injury at a proximal level of the terminal phalanx, but failed to regenerate despite conservative treatment and the presence of the nail organ. These clinical and experimental findings expand on previously published observations and initiate a molecular assessment of a mammalian regeneration model. Author Affiliation: (a) Division of Developmental Biology, Department of Cell and Molecular Biology, Tulane University, New Orleans, LA 70118, USA (b) The Center for Bioenvironmental Research, Tulane University, New Orleans, LA, USA (c) Department of Orthopaedics and Sports Medicine, University of Washington, Seattle, WA, USA Article History: Received 31 October 2007; Revised 13 December 2007; Accepted 13 December 2007

In the fault classification process, filter methods that sequentially remove unnecessary features have long been studied. However, the existing filter methods do not have guidelines on which, and how many, features are needed. This study developed a multi-filter clustering fusion (MFCF) technique, to effectively and efficiently select features. In the MFCF process, a multi-filter method combining existing filter methods is first applied for feature clustering; then, key features are automatically selected. The union of key features is utilized to find all potentially important features, and an exhaustive search is used to obtain the best combination of selected features to maximize the accuracy of the classification model. In the rotating machinery examples, fault classification models using MFCF were generated to classify normal and abnormal conditions of rotational machinery. The obtained results demonstrated that classification models using MFCF provide good accuracy, efficiency, and robustness in the fault classification of rotational machinery. [ABSTRACT FROM AUTHOR]

Byline: Jangwoo Lee, Yongwoon Gang The primary purpose of this study was to introduce an up-surging trend of technological entrepreneurship in Korea during the last decade and to determine how governmental policy for promoting technology-based small ventures impacts on job creation and innovation at the firm level. This study demonstrated that the high-tech ventures enrolled and systematically supported by the Korean Government achieved a significantly higher level of innovation and job creation than other small firms. Entrepreneurs of those ventures possessed a higher level of education and innovative attitude and they tended to employ differentiation strategies more aggressively and utilise more cooperative networks for acquiring external resources. It also showed that the membership of governmental enrolment had more influence on their performance than the managerial factors did. Those results suggest that systematic benefits from the governmental side more strongly affect a technology-based venture's performance and support the argument about the institutional theories. This study implicates that governmental policy for promoting technological entrepreneurship can contribute to the vitalisation of the national economy through the generation of new jobs and innovations.

Response of antibiotic resistance genes (ARGs) and heavy metal resistance genes (HMRGs) to two different temperature sequences (i.e., mesophilic-thermophilic and thermophilic-mesophilic) were investigated. Higher removal of total ARGs (twenty-one targeted subtypes) and HMRGs (three targeted subtypes) was achieved by the mesophilic-thermophilic sequence than by the thermophilic-mesophilic sequence. The sequence of mesophilic-thermophilic showed the highest removal of total ARGs, but the sequence of thermophilic-mesophilic proved more suitable for removal of class 1 integrons ( intI1 ). Correlation analysis indicated that intI1 correlated significantly with tetG , tetQ , tetX , sul2 , aac(6′)-lb-cr , bla TEM , ermB and floR . High-throughput sequencing revealed that the mesophilic-thermophilic sequence TPAD removed more human bacterial pathogens (HBPs) than did the thermophilic-mesophilic sequence. Also, significantly positive correlation was observed between ARGs and HBPs. For instance, Mycoplasma pneumonia showed significantly positive correlation with several ARGs including tetE , tetQ , tetX , tetZ , sul1 , sul2 , aac(6′)-lb-cr and floR . [ABSTRACT FROM AUTHOR]

Several studies suggested potential links of phthalates to stress-related outcomes. However, limited evidence has been available for the relationships between phthalate metabolites and free cortisol and 8-hydroxy-2′-deoxyguanosine (8-OHdG) in perinatal and postnatal environments. Therefore, we evaluated the relationships between phthalate metabolites and free cortisol and 8-OHdG in mother–child pairs. We repeatedly collected urine samples of 287 mother–child pairs from just before delivery to 15 months of age to measure the levels of four phthalate metabolites – mono-(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP), mono-(2-ethyl-5-oxohexyl) phthalate (MEOHP), mono-isobutyl phthalate (MiBP), and mono- n -butyl phthalate (MnBP) – and free cortisol and 8-OHdG. We used linear mixed effect models and generalized additive mixed models to estimate the relationship between the phthalate metabolites and free cortisol and 8-OHdG after adjusting for the child's gender, urine collection time, and maternal smoking status. The four phthalate metabolite levels were strongly correlated each other (all, p  < .0001), and intra-class correlation for each metabolite in children ranged from 0.18 to 0.96. All four phthalate metabolites were positively associated with both free cortisol (MEHHP, β = 0.18 and p  < .0001; MEOHP, β = 0.17 and p  < .0001; MiBP, β = 0.13 and p  = .0001; MnBP, β = 0.21 and p  < .0001; and molar sum of metabolites, β = 0.21 and p  < .0001) and 8-OHdG (MEHHP, β = 0.20 and p  < .0001; MEOHP, β = 0.18 and p  < .0001; MiBP, β = 0.23 and p  < .0001; MnBP, β = 0.28 and p  < .0001; and molar sum of metabolites, β = 0.29 and p  < .0001) in childhood. Our findings suggest that phthalate exposures increase free cortisol and 8-OHdG levels in early childhood. [ABSTRACT FROM AUTHOR]

Bisphenol A (BPA) exposure during the perinatal and postnatal periods increases the susceptibility to disease over the life cycle. However, information on the BPA delivered to fetuses or infants via the placenta and breastfeeding is limited. We determined the BPA exposure levels in various bodily fluids and tissues of pregnant women and described fetus and infant exposures to BPA based on associations and BPA ratios in mother–neonate paired samples. Maternal serum, urine, placenta, breast milk, cord serum, and neonatal urine samples were collected from 318 mother–neonate pairs at six university hospitals in Korea. BPA levels were detected using liquid chromatography tandem mass spectrometry. The ratios of the BPA levels in the other sample types to the levels in maternal serum were calculated. BPA was detected in 79.5–100% of the maternal and fetal samples. The median BPA concentration in the samples decreased in the order of neonatal urine (4.75 ng/mL), maternal urine (2.86 ng/mL), cord serum (1.71 ng/mL), maternal serum (1.56 ng/mL), breast milk (0.74 ng/mL), and the placenta (0.53 ng/g). We estimated the ratios of BPA levels in the other sample types to those in maternal serum. The median (95th percentile) cord serum-to-maternal serum ratio was 1.12 (15.2) for 160 mother–fetal pairs, in which BPA was detected in both samples. The placenta-, maternal urine-, neonatal urine-, and breast milk-to-maternal serum ratios were 0.28 (5.31), 1.79 (29.9), 1.98 (28.2), and 0.51 (10.5), respectively. In addition, the median (95th percentile) cord serum-to-placenta ratio was 4.03 (45.8), and the neonatal urine-to-cord serum ratio was 1.95 (25.6). The 95th percentile values were 14–20-fold greater than the medians. Urine contained the highest BPA concentrations, followed by serum, breast milk, and the placenta. The variations of BPA ratio show individual differences in the amounts of BPA delivered from mother to fetus. [ABSTRACT FROM AUTHOR]

Phthalates are important group of endocrine disruptors. Infants and young children are susceptible to phthalate exposure. However, information on the phthalate exposure during the early stages of life is very limited. This study was conducted to understand the temporal trend of exposure to major phthalates among infants of Korea during the first 15 months after birth, and to estimate associated risks. A total of 286 urine samples were collected from 171 children at 3, 9, 12, or 15 months of age, with 77 children sampled for two or more times. Four phthalates, i.e., di(2-ethylhexyl) phthalate (DEHP), di-isobutyl phthalate (DiBP), di-n-butyl phthalate (DnBP), and diethyl phthalate (DEP) were chosen, and their major metabolites were analyzed in the urine. The DEHP metabolites were detected in 100% of the urine samples at relatively higher levels compared to those reported in other countries. The levels of mono-ethyl phthalate (MEP) were generally lower. Urinary concentrations of most phthalate metabolites, especially DEHP metabolites, increased as children grew older. Intra-class correlation coefficients (ICCs) calculated for DEHP metabolites over time were high (0.7–0.8), suggesting persistence of consistent exposure sources during this sensitive period of life. Hazard quotient (HQ) and hazard index (HI) were calculated from daily intake estimates divided by recommended toxicity thresholds. Among the study population, 4, 16, and 26% of the children showed HI > 1 at 9, 12, and 15 months of age, respectively. DEHP exposure explained most of the risk estimates. Considering vulnerability of young children to endocrine disruption, efforts to identify sources of exposure and to develop appropriate mitigation options are warranted. [ABSTRACT FROM AUTHOR]

In this study, quantitative and qualitative changes in antibiotics resistance genes (ARGs) were investigated in two municipal wastewater treatment plants (WWTPs) treating pretreated livestock or industrial wastewater as well as municipal sewage. Total eight ARGs ( tet X, tet M, tet A, sul 1, sul 2, erm B, qnr D, and bla TEM ) were quantified, and their relative abundance was assessed by ARGs copies/16S rRNA gene copies. The fate of ARGs was observed to be different between two WWTPs: sul , qnr D, and bla TEM were proliferated during the treatment processes only in the WWTP1 which received pretreated livestock wastewater. Furthermore, dynamic shifts in patterns of ARGs occurrence were observed during biological, secondary sedimentation and coagulation processes. During biological treatment in both WWTPs, relative abundance of tet and erm B changed: tet increased significantly by 211.6–357.6%, while erm B decreased by 70.4–92.0%. Little variation was observed in sul , qnr D and bla TEM . Subsequently, the relative abundance of tet decreased during the secondary sedimentation and coagulation in both WWTPs: tet decreased by 56.0–86.3% during sedimentation and by 48.2–75.7% during coagulation, respectively. During the final treatment, different responses of antibiotic resistance bacteria (ARB) and ARGs to ultraviolet (UV) disinfection were found: removal efficiencies of ARB were observed in the range of 34–75%, while obvious reduction in ARGs was not observed at the UV dose of 27 mJ/cm 2 . Although ARGs underwent various treatment processes, considerable levels of ARGs remained at discharge amounting to 4.2 × 10 18 copies/day from WWTP1 and 5.4 × 10 16 copies/day from WWTP2, respectively. [ABSTRACT FROM AUTHOR]

In this research, the distribution of antibiotic resistance genes (ARGs) was characterized in representative organic solid waste (OSW) in Korea: food waste-recycling wastewater (FRW), manure, and sewage sludge. The amounts of total ARG (gene copies/16S rRNA gene copies) was greatest in manure followed by sewage sludge and FRW. Interestingly, there were significantly different patterns in the diversity and mechanisms of ARGs. For example, a significant proportion of ARGs were tetracycline resistant genes in all the OSW (40.4–78.2%). β-lactam antibiotics resistant genes were higher in the FRW samples than in other types of OSW but sulfonamides resistant genes represented the greatest proportion in sludge. Regarding the characteristics of antibiotic resistance mechanisms, there was a relatively higher proportion of the ribosomal protection mechanism to tetracycline observed in the FRW and manure samples. However, tetracycline resistant genes with direct interaction were relatively higher in the sewage sludge samples. sul 1 was the dominant subtype in all the OSW types and detection of erm B was observed although there was no erm C detected in sewage sludge. There were significant correlations between the occurrences of ARG subtypes: tet B and tet G in all OSW ( P < 0.01); tet E and tet Q only in sludge ( P < 0.01). The Class 1 integron-integrase gene ( intI 1) was significantly correlated with total ARGs only in manure and sludge ( P < 0.05), revealing potential horizontal gene transfer in these OSW. [ABSTRACT FROM AUTHOR]

Patents are widely used in the literature as a measure of firm-level innovation. It is regarded that patents improve a firm’s operational environment and ultimately increase the value of the firm. However, the relationship between patents and firm value in Korea is under-explored in the literature due to the difficulty of constructing datasets. This paper examines whether patents in Korea increase the market value of a firm. To do this, I exploit novel data on firm-level patents and financial information of all listed Korean companies during the period of 1993- 2015 and estimate the non-linear production-function type of Tobin’s q equations on R&D, patents, and citations. Surprisingly, I find that patents and citations are weakly associated with firm value, while R&D is strongly associated with an increase in firm value. These results direct imply that policymakers in Korea should enhance patenting incentives to encourage firms to innovate.