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In the widely used predictive regression model, any possible serial correlation in innovations leads to estimation bias and statistical inference distortions. Hence, it is important to pretest the existence of such serial correlation. Nevertheless, in the presence of embedded endogeneity, which is a common problem in the predictive regression setting, traditional serial correlation tests such as Box–Pierce (BP) and Ljung–Box (LB) tests are found to perform poorly. Motivated by this, we develop a new portmanteau test in this article as a pretest for serial correlation in predictive regression under possible embedded endogeneity. This test is based on the sample splitting idea and the jackknife empirical likelihood method. The asymptotic distribution of the proposed test has been derived, and the Monte Carlo simulations confirm good finite sample performances. As an illustration, we apply our proposed test in pretesting the serial correlation in predictive regression, where financial variables are used to predict the excess return of S&P 500. [ABSTRACT FROM AUTHOR]

It is well-known that the presence of serial correlation may result in an inefficient or even biased estimation in time series analysis. In this paper, we consider testing serial correlation in a general d-factor model when the model errors follow the GARCH process, which is frequently used in modeling financial data. Two empirical likelihood-based testing statistics are suggested as a way to deal with problems that might come up with infinite variance. Both statistics are shown to be chi-squared distributed asymptotically under mild conditions. Simulations confirm the excellent finite-sample performance of both tests. Finally, to emphasize the importance of using our tests, we explore the impact of the exchange rate on the stock return using both monthly and daily data from eight countries. [ABSTRACT FROM AUTHOR]

Background: The increasingly severe salinization of the aquatic environment has led to serious damage to the habitats of aquatic organisms. Benthic diatoms are commonly employed as indicator species for assessing water quality and serve as a reflection of the overall health of the aquatic ecosystem. Nitzschia palea is a common diatom found in freshwater, with high oil content, rapid reproductive rate, and it is a commonly dominant species in various rivers. Results: The results showed that after 4 days (d) of saline-alkali stress, the cell density and chlorophyll a content of Nitzschia palea reached their maximum values. Therefore, we selected Nitzschia palea under 4 d stress for Tandem Mass Tag (TMT) quantitative proteomic analysis to explore the molecular adaptation mechanism of freshwater diatoms under saline-alkali stress. Totally, 854 proteins were enriched, of which 439 differentially expressed proteins were identified. Gene ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and subcellular fractionation analysis revealed that these proteins were mainly enriched in the photosynthesis pathway, citric acid cycle (TCA cycle), fatty acid synthesis, and glutathione cycle. Conclusions: This study aims to reveal the physiological, biochemical and proteomic mechanisms of salt and alkali tolerance and molecular adaptation of Nitzschia palea under different saline-alkali concentrations. This study showed that Nitzschia palea is one candidate of the environmental friendly, renewable bioenergy microalgae. Meantime, Nitzschiapalea reveals for the proteome of the freshwater and provides the basis, it became a model algal species for freshwater diatoms. [ABSTRACT FROM AUTHOR]

The potential of Euglena gracilis for carbon sequestration offers significant opportunities in the capture and utilization of carbon dioxide (CO 2 ). In this study, a mutant LE-ZW of E. gracilis , capable of efficient growth and carbon sequestration, was obtained through ultraviolet mutagenesis combined with high carbon acclimation. Subsequently, the potential of LE-ZW for carbon assimilation was systematically analyzed. The results demonstrated that the cell density of the LE-ZW was 1.33 times that of the wild type and its carbon sequestration efficiency was 6.67 times that of the wild type when cultured at an optimal CO 2 concentration of 5% until day 10. At this time, most key enzyme genes associated with the photosystem membrane protein complex, photosynthetic electron transport chain, antenna protein, and carbon fixation were up-regulated in mutant LE-ZW. Furthermore, after 10 days of culture under 10% CO 2 , the cell density and carbon sequestration efficiency of LE-ZW reached 1.10 times and 1.54 times of that under 5% CO 2 , respectively. Transcriptome analysis revealed significant up-regulation of key enzyme genes associated with carbon fixation, central carbon metabolism, and photosynthesis in LE-ZW under a 10% CO 2 concentration. Physiological indices such as the amount of oxygen evolution, the values of Fv/Fm, the expression levels of photosynthetic protein genes and the enzyme activity of key enzymes related to photosynthetic carbon assimilation were corroborated by transcriptome data, elucidating that the mutant LE-ZW exhibited augmented photosynthetic carbon sequestration capacity and metabolic activity, thereby demonstrating robust adaptability to a high-carbon environment. This research contributes to a deeper understanding of the carbon assimilation mechanism in photosynthetic protists under elevated CO 2 concentrations., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Lv, Li, Du, Fan, Wang, Song, Sui and Liu.)

During the investigation of the freshwater diatoms from Tibet, a monoraphid species was observed from a hot spring near Anduo County, located on a plateau in the central portion of Tibet. This species shares the diagnostic features of Crenotia , such as the valve bent along the transapical axis, striae uniseriate to biseriate from centre to the apices and areolae with special structures located at the end of each stria. We compared the morphological characters of this new species with the others in this genus and show it to be new; it is named Crenotiatibetia sp. nov. This species has small valves with slightly protracted ends with nearly capitate apices, lanceolate axial area, central area unilaterally expanded to the margin, striae uniseriate to biseriate, but, in some valves, the striae are only uniseriate. Areolae are round small to irregular in shape and, at the end of each stria, there is a horseshoe-shaped areola present. Observations of developing valves show all the striae begin biseriate, then they become covered by silica to form uniseriate striae. Comparisons are made amongst the species in this genus and with genera assigned to the Achnanthidiaceae., Competing Interests: The authors have declared that no competing interests exist., (Xinyuan Na, Jiaming Liu, Ying Zhang, John Patrick Kociolek, Maxim Kulikovskiy, Xinxin Lu, Fengyang Sui, Huan Zhu, Guoxiang Liu, Yawen Fan, Yan Liu.)

Androgenetic alopecia (AGA) is the most prevalent form of progressive hair loss disorder in both men and women, significantly impacting their appearance and overall quality of life. Overactivation of the AR signaling pathway in dermal papilla cells (DPCs) plays a crucial role in the development and progression of AGA. Considering the severe systemic side effects associated with oral AR antagonists, the idea of developing of topical AR antagonists with rapid metabolic deactivation properties emerged as a promising approach. Herein, through systematic structural optimization, we successfully identified compound 30a as a potent and selective AR antagonist with favorable pharmacokinetic properties, resulting in high skin exposure and low plasma exposure following topical administration. Importantly, in both hair-growth and AGA mouse models, compound 30a showed potent hair-growth-promoting effects without any noticeable toxicity. These findings suggest that compound 30a holds significant potential as a topical AR antagonist for treating AGA patients.