Combined Quantile Forecasting for High-Dimensional Non-Gaussian Data

This study proposes a novel method for forecasting a scalar variable based on high-dimensional predictors that is applicable to various data distributions. In the literature, one of the popular approaches for forecasting with many predictors is to use factor models. However, these traditional methods are ineffective when the data exhibit non-Gaussian characteristics such as skewness or heavy tails. In this study, we newly utilize a quantile factor model to extract quantile factors that describe specific quantiles of the data beyond the mean factor. We then build a quantile-based forecast model using the estimated quantile factors at different quantile levels as predictors. Finally, the predicted values at the various quantile levels are combined into a single forecast as a weighted average with weights determined by a Markov chain based on past trends of the target variable. The main idea of the proposed method is to incorporate a quantile approach to a forecasting method to handle non-Gaussian characteristics effectively. The performance of the proposed method is evaluated through a simulation study and real data analysis of PM2.5 data in South Korea, where the proposed method outperforms other existing methods in most cases

Acceleration of X-chromosome gene order evolution in the cattle lineage

The gene order on the X chromosome of eutherians isgenerally highly conserved, although an increase in the rate ofrearrangement has been reported in the rodent lineage.Conservation of the X chromosome is thought to be caused byselection related to maintenance of dosage compensation.However, we herein reveal that the cattle (Btau4.0) lineage hasexperienced a strong increase in the rate of X-chromosomerearrangement, much stronger than that previously reported forrodents. We also show that this increase is not matched by asimilar increase on the autosomes and cannot be explained byassembly errors. Furthermore, we compared the difference intwo cattle genome assemblies: Btau4.0 and Btau6.0 (Bostaurus UMD3.1). The results showed a discrepancy betweenBtau4.0 and Btau6.0 cattle assembly version data, and webelieve that Btau6.0 cattle assembly version data are not morereliable than Btau4.0. [BMB Reports 2013; 46(6): 310-315

Current Status of Biportal Endoscopic Decompression for Lumbar Foraminal Stenosis: Endoscopic Partial Facetectomy and Outcome Factors

Degenerative lumbar foraminal stenosis is relatively common condition in which the circumferential narrowing of the space available for the nerve root leads to back pain and radicular symptoms. The preferred surgical treatment to relieve the compression of the nerve root has not been established yet. Recently, several reports have shown good clinical outcomes in patients who underwent biportal endoscopic decompression for the treatment of degenerative lumbar foraminal stenosis. The floating-type biportal endoscopic technique could be used with various surgical instruments without docking in the narrowed foramen, unlike the full-endoscopic technique. Multiple sites can be accessed with more freedom in the approaching angle through triangulation and portal switching. We reviewed articles to understand putative outcome factors and discuss the appropriate indications for biportal endoscopic foraminal decompression. Lumbar lordosis, degenerative lumbar scoliosis, height of the posterior intervertebral disc and level of procedure were all related to clinical outcomes. The best indications and contraindications to the endoscopic foraminal decompression still depends on the surgeon’s skill level and evolving experience. However, we could suggest that biportal endoscopic spinal surgery is supposed to be an alternative treatment for foraminal decompression preserving motion and stability, and decreasing the need for fusion surgery in various lumbar degenerative disease

Friction Tubes to Generate Nanobubble Ozone Water with an Increased Half-Life for Virucidal Activity

Nanobubbles and related technologies are expected to be highly utilized in water resource-based industries such as water purification, crops, horticulture, medicine, bio, and sterilization. Ozone, a chemical with high sterilizing power, is known as a natural substance that is reduced to oxygen and water after reacting with pollutants. Ozone water, which is generated by dissolving ozone in water, has been used in various industrial sectors such as medical care, food, and environment. Due to the unstable molecular state of ozone, however, it is difficult to produce, use, and supply ozone at industrial sites in a stable manner. This study proposed a method for constructing a system that can generate high-concentration ozone water in large quantities using low power in real time and maintaining the concentration of the generated ozone water over the long term. Friction tubes (called 'nanotube') played a key role to generate nanobubble ozone water with an increased half-life for virus killing activity. In addition, the safety of ozone water during its spray into the air was explained, and virucidal activity test cases for the influenza A (H1N1/A/PR8) and COVID-19 (SARS-CoV-2) virus using high-concentration ozone water as well as its technical efficacy were described