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In this research, we are concerned with intraday volatilities computed by functional ARCH(1) (fARCH(1), for short) model for high-frequency financial time series. A conditional-Copula multiple change point detection (CPD) for intraday volatilities is proposed using fARCH(1), bivariate Gaussian Copula and t-Copula conditional distributions. We employ current available multivariate CPD models which include energy test based control chart (ETCC) and nonparametric multivariate change point model (NPMVCP) to implement the proposed CPD method for the intraday volatilities. A simulation study is conducted to demonstrate that the functional ARCH based conditional-Copula CPD for the intraday volatilities can be a useful econometrics method to detect abnormal intraday volatilities in the financial market. We analyze intraday volatilities of the Korea composite stock price index (KOSPI) and the Hyundai-Motor (HDM) company stock data with one minute high-frequency to illustrate our proposed CPD method. [ABSTRACT FROM AUTHOR]

In this research, we are interested in finding the hidden dependence structure of sparse longitudinal data. Finding the hidden dependence structure of sparse longitudinal data is difficult due to the starting and end times being different. We propose that finding the directional dependence structure of the eigenfunctions by sparse functional principal component analysis (FPCA) may be a good alternative solution to find the hidden dependence structure of sparse longitudinal data. To verify this idea, we apply sparse FPCA to simulated data and two real datasets, wage sparse longitudinal data and Korea composite stock price index (KOSPI) high-frequency minute tick data and then apply vine copula and copula dynamic conditional correlation with asymmetric GARCH model to the functional eigenfunctions from FPCA. [ABSTRACT FROM AUTHOR]

The Dickey-Fuller test (DF test) and its various modified versions have been widely used for unit root or random walk testing, though advices are necessary regarding their proper use in hands-on statistical algorithm software. In this paper, we review the development of such tests over several decades. We examine why such modified versions of DF tests were developed and proper instructions regarding their use are essential. In addition, we discuss a simple way to overcome this hurdle. [ABSTRACT FROM AUTHOR]

Importance: Early diagnosis of canine pancreatitis is challenging due to non-specific clinical signs. Currently, abdominal ultrasonography and measurement of canine pancreatic lipase (cPL) have been employed for the diagnosis of pancreatitis., Objective: Many qualitative and quantitative commercial cPL tests have been developed and used in veterinary clinics. This study aimed to compare three different methodologies SNAP cPL, Spec cPL, and Vcheck cPL tests to assess the concordance of these assays., Methods: Fifty serum samples were collected from 36 dogs with or without pancreatitis and subjected to SNAP cPL, Spec cPL, and Vcheck cPL tests. Agreement and correlation coefficients were calculated between the test results, and correlations were determined during the management of the patients., Results: The results of the three cPL assays were strongly correlated in 47/50 serum samples (94%). Cohen's kappa analysis between the Spec cPL and Vcheck cPL showed near perfect agreement (κ = 0.960, p < 0.001), SNAP cPL and Vcheck cPL (κ = 0.920, p < 0.001), and Spec cPL and SNAP cPL (κ = 0.880, p < 0.001). The correlation coefficients ( r ) between data from Spec cPL and Vcheck cPL tests was calculated by Spearman's correlation test ( r = 0.958, p < 0.001). Furthermore, the patterns of change in serum cPL concentrations determined using Spec cPL and Vcheck cPL were significantly consistent during the monitoring period in 11 patients., Conclusions and Relevance: Our data illustrated that Spec cPL and Vcheck cPL tests are compatible for clinical use in the diagnosis and monitoring of canine pancreatitis., Competing Interests: Jungho Kim and Soungjin Ji are the Director and Associate Director of the R&D department of Bionote Inc., respectively. The remaining authors declare no conflicts of interest., (© 2024 The Korean Society of Veterinary Science.)

Background: Asherman's syndrome (AS) is a dreadful gynecological disorder of the uterus characterized by intrauterine adhesion with severe fibrotic lesions, resulting in a damaged basalis layer with infertility. Despite extensive research on overcoming AS, evidence-based effective and reproducible treatments to improve the structural and functional morphology of the AS endometrium have not been established. Methods: Endometrial organoids generated from human or mouse endometrial tissues were transplanted into the uterine cavity of a murine model of AS to evaluate their transplantable feasibility to improve the AS uterine environment. The successful engraftment of organoid was confirmed by detection of human mitochondria and cytosol (for human endometrial organoid) or enhanced green fluorescent protein signals (for mouse endometrial organoid) in the recipient endometrium. The therapeutic effects mediated by organoid transplantation were examined by the measurements of fibrotic lesions, endometrial receptivity and angiogenesis, and fertility assessment by recording the number of implantation sites and weighing the fetuses and placenta. To explore the cellular and molecular mechanisms underlying the recovery of AS endometrium, we evaluated the status of mitochondrial movement and biogenetics in organoid transplanted endometrium. Results: Successfully engrafted endometrial organoids with similar morphological and molecular features to the parental tissues dramatically repaired the AS-induced damaged endometrium, significantly reducing fibrotic lesions and increasing fertility outcomes in mice. Moreover, dysfunctional mitochondria in damaged tissues, which we propose might be a key cellular feature of the AS endometrium, was fully recovered by functional mitochondria transferred from engrafted endometrial organoids. Endometrial organoid-originating mitochondria restored excessive collagen accumulation in fibrotic lesions and shifted uterine metabolic environment to levels observed in the normal endometrium. Conclusions: Our findings suggest that endometrial organoid-originating mitochondria might be key players to mediate uterine repair resulting in fertility enhancement by recovering abrogated metabolic circumstance of the endometrium with AS. Further studies addressing the clinical applicability of endometrial organoids may aid in identifying new therapeutic strategies for infertility in patients with AS., Competing Interests: Competing Interests: The authors have declared that no competing interest exists., (© The author(s).)