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Extreme precipitation events are likely occur more frequently and lead to casualties and socio-economic losses as global warming intensifies. Therefore, exploring the characteristics of extreme precipitation events is essential. Based on meteorological station data from the middle and lower reaches of the Yangtze River Basin (MLYRB) from 1970 to 2018, we analyzed the spatiotemporal distributions of 11 extreme precipitation indices and considered the correlation between altitude and large-scale atmospheric circulation with extreme precipitation. To this end, we employed Sen's trend analysis, rescaled range analysis, the Mann-Kendall test, and continuous wavelet transform. The results indicate that on this spatial scale, extreme precipitation indices in the northwestern region of the MLYRB have mainly decreased, but they have increased along the eastern coastal region. From the perspective of the entire region, Hurst values of extreme precipitation indices are >0.5. Areas with consistent increases are mainly concentrated in the central region, while those with consistent decreases are mainly scattered in the northern and southern regions. Abrupt change in extreme precipitation indices mostly occurred in the 1980s and 1990s. The periodic oscillations of most indices tend toward high time-frequency scales (2.3 years or less). Consecutive wet days increased with increasing altitude; other indices changed similarly with increasing altitude, first increasing then decreasing before increasing again. Additionally, we found significant resonance periods between the extreme precipitation indices and the atmospheric circulation index, however, there were obvious differences in time domains. [ABSTRACT FROM AUTHOR]

Androgenetic alopecia (AGA) has become a widespread problem that leads to considerable impairment of the psyche and daily life. The currently approved medications for the treatment of AGA are associated with significant adverse effects, high costs, and prolonged treatment duration. Therefore, natural products are being considered as possible complementary or alternative treatments. This review aims to enhance comprehension of the mechanisms by which natural products treat AGA. To achieve this, pertinent studies were gathered and subjected to analysis. In addition, the therapeutic mechanisms associated with these natural products were organized and summarized. These include the direct modulation of signaling pathways such as the Wnt/β-catenin pathway, the PI3K/AKT pathway, and the BMP pathway. Additionally, they exert effects on cytokine secretion, anti-inflammatory, and antioxidant capabilities, as well as apoptosis and autophagy. Furthermore, the review briefly discusses the relationship between signaling pathways and autophagy and apoptosis in the context of AGA, systematically presents the mechanisms of action of existing natural products, and analyzes the potential therapeutic targets based on the active components of these products. The aim is to provide a theoretical basis for the development of pharmaceuticals, nutraceuticals, or dietary supplements. This review summarizes and describes the mechanisms by which natural products mitigate AGA and analyzes their potential structural target relationships. [Display omitted] • • Wnt/β-catenin pathway is the most important regulatory pathway for natural products to alleviate AGA. • • Mitochondria and TERT are novel targets for alleviating AGA. • • Flavonoids, mainly through the Wnt/β-catenin pathway, regulate the secretion of VEGF and TGF-β1 to promote hair growth. [ABSTRACT FROM AUTHOR]

To investigate the variations of PM 2.5 and O 3 and their synergistic effects with influencing factors at different time scales, we employed Bayesian estimator of abrupt seasonal and trend change to analyze the nonlinear variation process of PM 2.5 and O 3. Wavelet coherence and multiple wavelet coherence were utilized to quantify the coupling oscillation relationships of PM 2.5 and O 3 on single/multiple meteorological factors in the time-frequency domain. Furthermore, we combined this analysis with the partial wavelet coherence to quantitatively evaluate the influence of atmospheric teleconnection factors on the response relationships. The results obtained from this comprehensive analysis are as follows: (1) The seasonal component of PM 2.5 exhibited a change point, which was most likely to occur in January 2017. The trend component showed a discontinuous decline and had a change point, which was most likely to appear in February 2017. The seasonal component of O 3 did not exhibit a change point, while the trend component showed a discontinuous rise with two change points, which were most likely to occur in July 2018 and May 2017. (2) The phase and coherence relationships of PM 2.5 and O 3 on meteorological factors varied across different time scales. Stable phase relationships were observed on both small- and large-time scales, whereas no stable phase relationship was formed on medium scales. On all-time scales, sunshine duration was the best single variable for explaining PM 2.5 variations and precipitation was the best single variable explaining O 3 variations. When compared to single meteorological factors, the combination of multiple meteorological factors significantly improved the ability to explain variations in PM 2.5 and O 3 on small-time scales. (3) Atmospheric teleconnection factors were important driving factors affecting the response relationships of PM 2.5 and O 3 on meteorological factors and they had greater impact on the relationship at medium-time scales compared to small- and large-time scales. [Display omitted] • Nonlinear variations of PM 2.5 and O 3 in "2 + 26" cities were evaluated. • Relationships of PM 2.5 and O 3 on impact factors quantified by wavelet perspective. • SSD was the best single variables to explain PM 2.5 variations on all time scales. • PRE was the best single variables to explain O 3 variations on all time scales. • AO, PDO and ENSO mainly influenced the response relationship at medium time scale. [ABSTRACT FROM AUTHOR]

Soil nematode communities and their functions are simultaneously influenced by abiotic factors such as temperature and soil moisture. However, the complex interaction effects of these factors have not been clearly demonstrated, limiting our understanding of soil biodiversity and functions under different climate scenarios. Here, we conducted a short-term microcosm experiment, implementing three temperature treatments (20 °C, 25 °C, and 30 °C) combined with two soil moisture treatments (50% and 80% water-holding capacity). We comprehensively assessed the changes in abundance, diversity, composition, and functions (carbon footprints) of soil nematode communities under these different treatments. Our findings revealed that temperature and moisture did not have significant effects on the richness or Shannon diversity of nematodes, while they did have significant impacts on other properties. We found that the interaction effect between temperature and moisture had a greater influence on total abundance compared to their independent effects. Moisture emerged as the primary driver of nematode community composition, followed by the interaction term, while temperature exhibited the least influence. Contrary to expectations, increasing temperature did not cause a shift in the community towards small-bodied genera when considering intraspecific variability in body mass. However, elevating moisture level led to an increase in community-weighted mean body mass, irrespective of intraspecific variability. Consequently, the body-mass-related footprints varied among treatments when considering intraspecific variability, with the dominant influence arising from the interaction effect. Overall, our study highlights the dominant interaction effect of temperature and soil moisture on multiple ecological properties of nematode communities. Additionally, we underscore the importance of incorporating intraspecific trait variability when assessing the responses and functions of nematodes under distinct environmental conditions. [ABSTRACT FROM AUTHOR]

• Used ITA, IPTA to analyze precipitation at multiple time-scales. • Multiscale and multivariate analyses of large-scale circulation on precipitation. • The combination of AO-PDO-ENSO-EASM-SOI-SSPI can best explain the change of precipitation. Precipitation is an important variable affecting regional climate characteristics. Accurately identifying trends in precipitation is essential for understanding the evolution of the water cycle in the context of climate change. This study uses an innovative trend analysis (ITA), an innovative polygon trend analysis (IPTA), and wavelet analysis to analyze precipitation at multiple timescales (annual, seasonal, and monthly), and the influencing factors at 30 meteorological stations in the Tai Lake Basin (TLB) from 1971 to 2018. The main conclusions are as follows: 1) the annual precipitation had a significantly increasing trend, while high precipitation had the largest increasing trend, leading to a further increase in the flood risk in the TLB. The precipitation trend mainly decreased in spring and autumn, whereas it mainly increased in summer and winter. Precipitation in different months played crucial but varying roles in the corresponding seasons; there was a sharp transition trend from August to September, whereas the transition from January to February was relatively stable. 2) There was a complex non-linear relationship between precipitation and atmospheric teleconnection. The dominant tele-correlation alone could not explain the relationship between precipitation and large-scale circulation. The highest percentage of significant power includes the optimal combination of variables meant to explain the precipitation variations. 3) The detection results from the ITA method and classic trend analysis methods (Linear regression analysis, Mann Kendall, and Modified Mann Kendall) were consistent; the non-monotonic trends masked by these methods were detectable. IPTA can systematically identify consecutive seasons and monthly transition characteristics as a supplement to ITA. This study can, therefore, provide a reference for water resource management and the prevention and control of droughts and floods. [ABSTRACT FROM AUTHOR]

Abstract: Flow cytometric detection of mitochondrial H2S was achieved with propargylic esters of rhodamine B which selectively react with H2S via cationic rhodamine-moiety directed thiolysis of the propargylic esters to give nonfluorescent rhodamine thio-spirolactone. [Copyright &y& Elsevier]

Polyploidization (i.e., multiplication of genome size) is a major driver of plant evolution and is believed to play a significant role in plant invasion. One hypothesis states that polyploids possess larger root systems with increased root exudation and thus, induce a greater effect on the rhizosphere compared to their diploids counterparts. Few experiments, however, have explicitly tested the impacts of the polyploidy of plants on soil organisms in the field. Using a common garden approach, we examined the impacts of native and introduced populations of Solidago canadensis with differing ploids (diploid, tetraploid and hexaploid) on soil microbes, nematodes, and carbon (C) - nitrogen (N) turnover. Polyploidy generally increased microbial biomass in soil: while the biomass of all microbial groups was significantly higher under introduced than native tetra- and hexa-ploids, there was no significant difference in soil bacteria, fungi, and actinomycetes between diploids of the native and introduced populations. The effect of polyploids on soil microbial biomass was greater in November than July, suggesting that the effect becomes stronger later in the growing season. The impact of polyploidy on nematodes was largely dependent on trophic status; polyploids did not significantly affect bacterivores or omnivores + carnivores, but tended to increase the abundance of fungivores, and significantly increased the number of herbivores. Extraradical biomass of arbuscular mycorrhizal fungi was significantly higher, but NO 3 −-N and the net nitrification rate were significantly lower under tetra- and hexa-ploids than diploids. Together, these results suggest that polyploidization induces rhizosphere processes that improve plant nutrition and contribute to plant invasiveness through stimulation of soil microbial biomass and increased biological activity. Different trophic interactions in the rhizosphere of diploid and polyploids Solidago canadensis. Compared to diploid plants (a), polyploid plants (b) possess larger root systems associated with more arbuscular mycorrhizal fungi (AMF), bacteria and fungi. Higher resource availability subsequently increases fungi-feeding nematodes and plant-feeding nematodes, leading to more N release and plant N uptake through roots and AMF (i.e., a positive plant-soil feedback). (BF: bacterivorous; FF: fungivorous; HE: herbivorous; OM + CA: omnivorous-carnivorous nematodes.). Image 1 • Ploidy effects of Solidago canadensis on plant-microbe interactions were studied. • Mycorrhizal root infection and plant N uptake were higher in poly-than di-ploids. • Polyploids enhanced soil microbial biomass, respiration and N mineralization. • Fungal- and root-feeding nematodes were more abundant under poly-than di-ploids. [ABSTRACT FROM AUTHOR]

• Nicotine upregulates α 4 β 2 -nAChRs, inhibits neuroinflammation and improves cognition. • Celecoxib inhibits neuroinflammation and improves cognition. • Combined nicotine and celecoxib attenuate cognitive impairment more effectively. The contribution of neuroinflammation in cognitive impairment is increasingly recognized. Non-steroidal anti-inflammatory drugs had been proven that it could improve cognitive impairment in large dose but with more side effect, which limited the application. The main objective of this study was to investigate whether the combined use of nicotine and celecoxib could obtain synergistic neuroprotective effect in ischemic rats. Twenty adult Sprague-Dawley (SD) rats underwent ischemic model surgery by injecting endothelin-1 into the left thalamus, which were classified into four groups with different interventions: nicotine (1.5 mg/kg/d), celecoxib (15 mg/kg/d), nicotine (1.5 mg/kg/d) +celecoxib (15 mg/kg/d), or saline after surgery. The other five SD rats also underwent same surgery by injecting saline instead of endothelin-1, as the control group. Morris water maze (MWM) test was adopted to assess the cognition. Micro PET/CT with 2-[18F]-A-85380 were performed for α 4 β 2 -nAChRs detection in vivo. Western blot, real-time PCR and immunohistochemical staining were adopted to detect the expression of α 4 β 2 -nAChRs and inflammatory factors which included TNF-α, IL-1β, IL-6 in brain tissue. Microglial activation in the brain was monitored by immunofluorescence with IBA1 staining. The MWM test showed rats given with nicotine or celecoxib alone showed much better memory than rats with saline, no difference was observed between nicotine and celecoxib. The rat memory was recovered most significant when the nicotine and celecoxib were combined (p < 0.05). Micro-PET/CT showed much more tracer uptake in the left thalamus and whole brain in rats given with nicotine, or nicotine + celecoxib (nico + cele group) than saline treated rats, whereas the rats given celecoxib did not. Compared with saline treated rats, we found the proteins of α 4 nAChR and β 2 nAChR in rats given nicotine or nico + cele increased significantly, and mRNA/proteins of TNF-α, IL-1β and IL-6 decreased at the same time. The α 4 nAChR and β 2 nAChR proteins in rats given celecoxib is the same as saline treated rats, whereas the inflammatory factors decreased obviously compared with saline treated rats. Microglial activation was confirmed in saline treated rats, which was inhibited in rats give nicotine, celecoxib or both. The study revealed the combined use of nicotine and celecoxib may improve the cognitive function in ischemic rats, with a better effect than either alone. Both nicotine and celecoxib can inhibit inflammation, but through different mechanisms: nicotine can activate α 4 β 2 -nAChRs while celecoxib is cyclooxygenase-2 inhibitor. Our findings suggest the combined application of two drugs with different anti-inflammation mechanism could attenuate cognitive impairment more effectively in ischemic rats, which may hold therapeutic potential in the clinical practice. [ABSTRACT FROM AUTHOR]

Site-specific Fe2+ generation is promising for tumor therapy. Up to now, reported materials or systems for Fe2+ delivery do not naturally exist in the body, and their biological safety and toxicity are concerned. Herein, inspired by the natural biomineral ferrihydrite in ferritin, we synthesized monodispersed ferrihydrite nanoparticles and demonstrated a light triggered Fe2+ generation on tumor sites. Ferrihydrite nanoparticles of 20–30 nm in diameter possessed high cellular uptake efficiency and good biocompatibility. Under common blue light illumination, a large amount of Fe2+ could be released from ferrihydrite and promote the iron/reactive oxygen species (ROS)-related irreversible DNA fragmentation and glutathione peroxidase 4 (GPX4) inhibition, which led to the apoptosis- and ferroptosis-depended cancer cell proliferation inhibition. On mice, this method induced tumor associated macrophage (TAM) polarization from the tumor-promoting M2 type to the tumor-killing M1 type. With the intravenous pre-injection of ferrihydrite, the combinational effects of the light/Fe2+-approach attenuated pulmonary metastasis on mice. These results demonstrated a novel external light controlled Fe2+-generation approach based on biomineral, which will fully tap the anti-cancer potential of Fe2+ in chemo-dynamic, photo-dynamic and immune-activating therapies. [ABSTRACT FROM AUTHOR]

Abstract: Introduction: Differentiated thyroid carcinoma (DTC) usually has a high iodine uptake. However, dedifferentiation of DTC with decreased or no radioiodine (131I) uptake is observed in clinical practice, with poor prognosis. The aim of this study was to investigate the effects of 131I radiation on radioiodine uptake (RAIU) and the expression of thyroid-specific molecules. Methods: FTC-133 cells were treated with 131I, the dosage dictated by methylthiazol tetrazolium test results and preliminary experiments. The experimental cell group was incubated with 131I for 48 h and then cultured for 3 months in 131I-free medium. The control group was set without 131I. Primary cells were defined as the blank group. Following treatment, RAIU was measured with a gamma counter as the counts/cell number. Na+/I− symporter (NIS), thyroid-stimulating hormone receptor (TSHR), thyroid peroxidase (TPO) and thyroglobulin (Tg) levels were detected by Western blotting and radioimmunoassay, and their mRNAs were detected by real-time polymerase chain reaction. Results: RAIU of FTC-133 cells decreased gradually after coincubation with 131I and did not recover even if 131I was removed. The relative RAIU of the control and experimental groups was 0.567 and 0.182, respectively, a statistically significant difference (P<.01). Expression of NIS, TSHR, TPO and Tg decreased in the experimental group to a statistically significant degree compared to that of controls (P<.05). Conclusion: Changes in the mRNA levels were in accordance with the expression of thyroid-specific proteins. Thus, FTC-133 cells undergo dedifferentiation during long-term culture in vitro, and 131I may promote this progress. [Copyright &y& Elsevier]