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Mangroves are endemic forest communities in tropical and subtropical coastal zones. China's Hainan Island is very rich in mangrove plant species. In recent years, due to climate change and human disturbance, the living environment of many mangrove distribution areas has been seriously threatened. This study used land satellite series remote sensing images from 1990 to 2020 to monitor the coverage and area changes of mangroves on Hainan Island. The spatial distribution pattern and change trend of mangroves were explored using the standard deviation ellipse method, and the CA–Markov model was used to predict the possible changes of mangroves in the study area in 2025 and 2030. The development trend of mangroves in the future and the driving factors affecting the evolution of mangroves were also analyzed. Over the past 30 years, the area of mangroves has witnessed fluctuations. It decreased from 4578 hectares in 1990 to its lowest at 3870 hectares in 2005 and then rebounded to 4474 hectares by 2020, indicating an initial decline followed by a gradual increase. Although conservation and restoration efforts have yielded success, specific areas have witnessed a decline in mangrove coverage. From 1990 to 2020, mangrove areas in Huiwen decreased from 1055 hectares to 904 hectares, areas in Guannan decreased from 227 hectares to 167 hectares, areas in Xinyinggang decreased from 328 hectares to 298 hectares, areas in Yangpugang decreased from 747 hectares to 682 hectares, areas in Huachangwan decreased from 355 hectares to 327 hectares, and areas in Puqian decreased from 170 hectares to 141 hectares. In particular, the growth in the Eastern and Mayao port areas is especially significant. Additionally, data analysis has revealed the spatial distribution characteristics of mangroves in different regions, such as the mangrove area in Dongzhaigang, which remained relatively stable from 1990 to 2020, while in other areas like Huiwen and Guannan, the mangrove area decreased during these 20 years. By calculating the standard deviation ellipse, we observed that the overall change of mangroves on Hainan Island from 1990 to 2020 was relatively slow, mainly distributed along the northern coastal area of Hainan Island. Furthermore, the standard deviation ellipse and SDE center point of each mangrove growth area have visualized the growth trends of the mangroves. The Markov chain simulation results show that future changes in mangroves will mainly be concentrated in the marginal areas of the mangroves. These areas may be affected by rising sea levels, climate change, soil salinity, and human activities. In the future, mangrove areas are expected to display a dynamic equilibrium, experiencing periods of expansion and reduction, ultimately moving towards a more consistent state. To protect and restore mangroves, it is necessary to strengthen the monitoring and management of their ecological environment and socio-economic factors and improve their stability and diversity. [ABSTRACT FROM AUTHOR]

Africa is becoming one of the most sensitive and vulnerable regions of the global ecosystem due to its variable climate, complex topography, and diversity of natural ecosystems. In the context of global warming, climate change not only alters the spatial distribution of temperature and precipitation in North Africa, but also affects the spatial distribution of vegetation as well as the structure and function of ecosystems, causing changes in the North African ecosystem and inducing a series of food security problems. In this regard, this paper analyzed the spatio-temporal distribution of climate change, climate production potential (CPP), and influencing factors in Africa based on meteorological data for 1901–2019, using the Thornthwaite Memorial model, Mann–Kendall mutation test, and Pearson correlation model. The results indicated that from 1901 to 2019, the CPP in North Africa decreased by 4.9%, while the region's precipitation experienced a decline of 5.2%. The phased trend in CPP was consistent with the change in precipitation. Temperature and precipitation were the main limiting factors for CPP in North Africa, with precipitation being more limiting. In general, North Africa's CPP was more sensitive to precipitation, and a continued 'warm and dry' climate in the future could lead to an increasing downward trend. [ABSTRACT FROM AUTHOR]

Advanced oxidation processes (AOPs) demonstrate great micropollutant degradation efficiency. In this study, CuFe2O4 was successfully used to activate peracetic acid (PAA) to remove Rhodamine B. Acetyl(per)oxyl radicals were the dominant species in this novel system. The addition of 2,4-hexadiene (2,4-HD) and Methanol (MeOH) significantly inhibited the degradation efficiency of Rhodamine B. The ≡Cu2+/≡Cu+ redox cycle dominated PAA activation, thereby producing organic radicals (R-O˙) including CH3C(O)O˙ and CH3C(O)OO˙, which accounted for the degradation of Rhodamine B. Increasing either the concentration of CuFe2O4 (0–100 mg/L) or PAA (10–100 mg/L) promoted the removal efficiency of this potent system. In addition, weakly acid to weakly alkali pH conditions (6–8) were suitable for pollutant removal. The addition of Humid acid (HA), HCO3−, and a small amount of Cl− (10–100 mmol·L−1) slightly inhibited the degradation of Rhodamine B. However, degradation was accelerated by the inclusion of high concentrations (200 mmol·L−1) of Cl−. After four iterations of catalyst recycling, the degradation efficiency remained stable and no additional functional group characteristic peaks were observed. Taking into consideration the reaction conditions, interfering substances, system stability, and pollutant-removal efficiency, the CuFe2O4/PAA system demonstrated great potential for the degradation of Rhodamine B. [ABSTRACT FROM AUTHOR]

Research has been conducted on the acrylamide and aromatic aldehydes. Results indicate that at the ambient temperature in the aqueous medium these compounds undergo the Baylis-Hillman reaction producing 3-hydroxy-2-methylenepropionamides in the presence of the 1,4-diazabicyclo[2,2,2]octane base catalyst.

Research has been conducted on the conditions developed during the Baylis-Hillman reaction. The use of the stoichiometric base catalyst and the aqueous medium in investigating the problems associated with the Baylis-Hillman reaction such as low reaction yields and long reaction time is described.

An electron transfer system involving a combination of samarium(O) and 1,1'-dioctyl-4.4'-bipyridinium dibromide is described. The method can be used for chemoselective reduction of aromatic nitro compounds and is superior to the one that employs samarium(II) iodide in terms of the enhanced reduction potential of samarium(O).

A 2-(2'-hydroxyphenyl)-benzoxazole (HBO) is developed as a model base pair to study how the different environments within DNA affect tautomerization, as nucleoside-bearing HBO may be synthesized such that when incorporated into DNA, the enol moiety of the model base pair is positioned in either the major or minor groove. When HBO is incorporated in DNA such that the enol moiety is positioned in the minor groove, the enol tautomer is preferentially stabilized.

Abstract: Heart failure has become one of the top causes of death worldwide. It is increasing evidence that lncRNAs play important roles in the pathology processes of multiple cardiovascular diseases. Additionally, lncRNAs can function as ceRNAs by sponging miRNAs to affect the expression level of mRNAs, implicating in numerous biological processes. However, the functional roles and regulatory mechanisms of lncRNAs in heart failure are still unclear. In our study, we constructed a heart failure‐related lncRNA‐mRNA network by integrating probe re‐annotation pipeline and miRNA‐target interactions. Firstly, some lncRNAs that had the central topological features were found in the heart failure‐related lncRNA‐mRNA network. Then, the lncRNA‐associated functional modules were identified from the network, using bidirectional hierarchical clustering. Some lncRNAs that involved in modules were demonstrated to be enriched in many heart failure‐related pathways. To investigate the role of lncRNA‐associated ceRNA crosstalks in certain disease or physiological status, we further identified the lncRNA‐associated dysregulated ceRNA interactions. And we also performed a random walk algorithm to identify more heart failure‐related lncRNAs. All these lncRNAs were verified to show a strong diagnosis power for heart failure. These results will help us to understand the mechanism of lncRNAs in heart failure and provide novel lncRNAs as candidate diagnostic biomarkers or potential therapeutic targets. [ABSTRACT FROM AUTHOR]

In this study, performance of hydrolysis acidification process treating simulated dyeing wastewater containing azo and anthraquinone dyes in different stages was investigated. The decolorization ratio, COD removal ratio, BOD/COD value, and volatile fatty acids (VFAs) production were almost better in stage 1 than that in stage 2. Fourier transform infrared spectroscopy (FTIR) and gas chromatography-mass spectrometry (GC-MS) confirmed the biodegradation of Reactive Black 5 (RB5) and Remazol Brilliant Blue R (RBBR) in hydrolysis acidification process. Polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) analyses revealed that significant difference of microbial community structures existed in stage 1 and 2. The dominant species in stage 1 was related to Bacteroidetes group, while the dominant species in stage 2 was related to Bacteroidetes and Firmicutes groups. From the results, it could be speculated that different dyes' structures might have significant influence on the existence and function of different bacterial species, which might supply information for bacteria screening and acclimation in the treatment of actual dyeing wastewater. [ABSTRACT FROM AUTHOR]

We present a start-up method for complete autotrophic nitrogen removal via the nitrite (CANON) granular sludge process by controlling the DO concentration. More specifically, we initially increase the activity of anaerobic ammonia-oxidizing bacteria (AnAOB) and, subsequently, gradually increase the activity of ammonia oxidizing bacteria (AOB). The results indicate the optimum process parameters to be an 8 h reaction period and an aeration/non-aeration time ratio of 1.0 h/0.25 h. These conditions maintain a high activity for both AOB and AnAOB and are also conducive to sludge granulation. Following 64 days of continuous operation, the mean particle size of the sludge increased to 992 µm, while the proportion of granular sludge accounted for approximately 87.16%, and the proportion of sludge with a particle size ≥ 1000 µm was 36.66%. Both AOB and AnAOB became the dominant bacterial genera in the CANON reaction system, while nitrite-oxidizing bacteria were successfully discharged from the reaction system. [Display omitted] • A start-up method for CANON process by controlling DO concentration was presented. • CANON granulation improves nitrogen removal performance and stability. • HRT and aeration/non-aeration time affected nitrogen removal. • Proper aeration can maintain both a high AOB and AnAOB activity and abundance. [ABSTRACT FROM AUTHOR]

Fructose was utilized as an additional co-substrate to systematically investigate the molecular mechanism of its boosting effect for the degradation of refractory dye reactive black 5 (RB5) by a natural bacterial flora DDMZ1. A decolorizing rate of 98% was measured for sample YE + FRU(200) (with 3 g/L fructose additionally to yeast extract medium, 10% (v/v) inoculation size of flora DDMZ1, 200 mg/L RB5) after 48 h. This result was 21% and 77%, respectively, higher than those of samples with only yeast extract or only fructose. Fructose was found to significantly stimulated both intracellular and extracellular azoreductase secretion causing enhanced activity. Metagenomic sequencing technology was used to analyze the functional potential of genes. A label-free quantitative proteomic approach further confirmed the encoding of functional proteins by the candidate genes. Subsequently, the molecular mechanism of RB5 degradation by candidate genes and functional proteins of the dominant species were proposed. This study provides important perspectives to the molecular mechanism of co-metabolic degradation of refractory pollutants by a natural bacterial flora. Image 1 • Fructose as an additional co-substrate boosted the dye decolorization efficiency. • The metagenomic results were mostly consistent with metaproteomic ones. • Functional genes and proteins exhibited a strong correlation of dominant genera. • Possible molecular metabolic mechanism of RB5 was proposed. [ABSTRACT FROM AUTHOR]

Four sugar sources were used as co-substrates to promote the degradation of a selected refractory dye reactive black 5 (RB5) by the natural bacterial flora DDMZ1. The boosting performance of the four sugar sources on RB5 decolorization ranked as: fructose > sucrose > glucose > glucose + fructose. Kinetic results of these four co-metabolism systems agreed well with a first-order kinetic model. Four sugar sources stimulated the extracellular azoreductase secretion causing enhanced enzyme activity. An increased formation of low molecular weight intermediates was caused by the addition of sugar sources. The toxicity of RB5 degradation products was significantly reduced in the presence of sugar sources. The bacterial community structure differed remarkably as a result of sugar sources addition. For a fructose addition, a considerably enriched population of the functional species Burkholderia-Paraburkholderia and Klebsiella was noted. The results enlarge our knowledge of the microkinetic and microbiological mechanisms of co-metabolic degradation of refractory pollutants. • Sugar sources could significantly promote the degradation of refractory dye. • Different sugar sources result in different degradation pathways of RB5. • Sugar sources significantly reduced the toxicity of RB5 degradation products. • Burkholderia-Paraburkholderia and Klebsiella were functional microorganisms. [ABSTRACT FROM AUTHOR]

Conventional microbial treatments are challenged by new synthetic refractory dyes. In this work, tea residue was found serving as an effective activator to boost the decolorization performance of anthraquinone dye (reactive blue 19, RB19) by a new bacterial flora DDMY2. The unfermented West Lake Longjing tea residue showed the best enhancement performance. Seventeen main kinds of components in tea residue had been selected to take separate and orthogonal experiments on decolorization of RB19 by DDMY2. Results suggested epigallocatechin gallate (EGCG) in tea residue played important roles in boosting the treatment performance. Illumina MiSeq sequencing results confirmed that EGCG and tea residue pose similar impact on the change of DDMY2 community structure. Some functional bacterial genera unclassified_o_Pseudomonadales , Stenotrophomonas and Bordetella were enriched during the treatment of RB19 by EGCG and tea residue. These evidences suggested EGCG might be the key active component in tea residue that responsible for the enhancement effect on decolorization performance. These results revealed the activating mechanism of tea residue from the perspective of composition. • Unfermented West Lake Longjing tea residue showed the best enhancement effect. • EGCG played important roles in boosting the performance of decolorizing RB19. • Tea residue and EGCG posed similar impact on the change of community structure. • EGCG was the key component responsible for the enhancement performance. [ABSTRACT FROM AUTHOR]

In present study, a hydrolysis acidification (HA) reactor was used to deal with simulated dyeing wastewater containing Reactive Black 5 (RB5) and Remazol Brilliant Blue R (RBBR) in two stages, respectively. COD and color removal rate were detected to reveal the performance of the HA reactor. Results indicated that the color removal rate of HA reactor decreased from 66.12% to 24.00%, and 69.91%–18.01% in stage 1 and stage 2 as the concentration of dyes increased, respectively. In stage 1, the COD removal rate of HA reactor fluctuated around 50%, while in stage 2 it declined from 51.50% to 21.58% as the concentration of dyes increased. Illumina MiSeq sequencing analysis was performed to investigate the microbial community structure and diversity in the HA process under different dye conditions. The results revealed that different dyes (RB5 and RBBR) in HA process had significant influence on the microbial community structure at different taxonomic levels (from phylum to genus). Bacteroidetes , Proteobacteria and Firmicutes were dominant phyla in both two samples collected from two stages containing different dyes. The genera Klebsiella , Lactococcus , and Desulfovibrio might have potential ability of degrading both RB5 and RBBR under hydrolysis acidification condition, while Dysgonomonas sp. and Prevotella sp. might play important roles in RB5 and RBBR degradation, respectively, in this hydrolysis acidification process. [ABSTRACT FROM AUTHOR]

Summary: Alzheimer''s disease (AD) is characterized pathologically by the abundance of senile plaques and neurofibrillary tangles in the brain. We synthesized over 1200 novel gamma-secretase modulator (GSM) compounds that reduced Aβ42 levels without inhibiting epsilon-site cleavage of APP and Notch, the generation of the APP and Notch intracellular domains, respectively. These compounds also reduced Aβ40 levels while concomitantly elevating levels of Aβ38 and Aβ37. Immobilization of a potent GSM onto an agarose matrix quantitatively recovered Pen-2 and to a lesser degree PS-1 NTFs from cellular extracts. Moreover, oral administration (once daily) of another potent GSM to Tg 2576 transgenic AD mice displayed dose-responsive lowering of plasma and brain Aβ42; chronic daily administration led to significant reductions in both diffuse and neuritic plaques. These effects were observed in the absence of Notch-related changes (e.g., intestinal proliferation of goblet cells), which are commonly associated with repeated exposure to functional gamma-secretase inhibitors (GSIs). [Copyright &y& Elsevier]

Forkhead box L2 (FOXL2) is an indispensable key regulator of female follicular development, and it plays important roles in the morphogenesis, proliferation, and differentiation of follicle granulosa cells, such as establishing normal estradiol signaling and regulating steroid hormone synthesis. Nevertheless, the effects of FOXL2 on granulosa cell morphology and the underlying mechanism remain unknown. Using FOXL2 ChIP-seq analysis, we found that FOXL2 target genes were significantly enriched in the actin cytoskeleton-related pathways. We confirmed that FOXL2 inhibited the expression of RhoA, a key gene for actin cytoskeleton rearrangement, by binding to TCATCCATCTCT in RhoA promoter region. In addition, FOXL2 overexpression in granulosa cells induced the depolymerization of F-actin and disordered the actin filaments, resulting in a slowdown in the expansion of granulosa cells, while FOXL2 silencing inhibited F-actin depolymerization and stabilized the actin filaments, thereby accelerating granulosa cell expansion. RhoA/ROCK pathway inhibitor Y-27632 exhibited similar effects to FOXL2 overexpression, even reversed the actin polymerization in FOXL2 silencing granulosa cells. This study revealed for the first time that FOXL2 regulated granulosa cell actin cytoskeleton by RhoA/ROCK pathway, thus affecting granulosa cell expansion. Our findings provide new insights for constructing the regulatory network of FOXL2 and propose a potential mechanism for facilitating rapid follicle expansion, thereby laying a foundation for further understanding follicular development., (© The Author(s) 2024. Published by Oxford University Press on behalf of Society for the Study of Reproduction. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Influenza virus and SARS-CoV-2 virus are two important viruses that cause respiratory tract diseases. The high-frequency mutation of the two types of viruses leads to failure of the durable immune protection of vaccines, meanwhile it also poses continuous challenges to the development of antiviral drugs. Traditional Chinese medicine contains large number of biologically active compounds, and some of them contain broad-spectrum antiviral ingredients. In this study, we extracted antiviral active ingredients from medicinal and edible plants by biotransformation and enzymatic hydrolysis as a drug, and we named this drug Ren's oligopeptide. Further, we analyzed the antiviral activity of this drug and found that Ren's oligopeptide could inhibit the replication of influenza virus and SARS-CoV-2 virus with high anti-virus activities. In vitro experiments showed that the antiviral activity of the Ren's oligopeptide mainly targets the replication process after virus enters the cell. Therefore, Ren's oligopeptide is a promising drug against influenza and COVID-19., Competing Interests: XR was employed by Wuhan Shiji Maide Biotechnology Company. The remaining 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 © 2023 Yu, Huang, Ren and Sun.)

In efforts to obtain anticancer prodrugs for antibody-directed or gene-directed enzyme prodrug therapy using E. coli nitroreductase, a series of nitrobenzylphosphoramide mustards were designed and synthesized incorporating a strategically placed nitro group in a position para to the benzylic carbon for reductive activation. All analogues were good substrates of E. coli nitroreductase with half-lives between 2.9 and 11.9 min at pH 7.0 and 37 degrees C. Isomers of the 4-nitrophenylcyclophosphamide analogues 3 and 5 with a benzylic oxygen para to the nitro group showed potent selective cytotoxicity in nitroreductase (NTR) expressing cells, while analogues 4 and 6 with a benzylic nitrogen para to the nitro group showed little selective cytotoxicity despite their good substrate activity. These results suggest that good substrate activity and the benzylic oxygen are both required for reductive activation of 4-nitrophenylcyclophosphamide analogues by E. coli nitroreductase. Isomers of analogue 3 showed 23,000-29,000x selective cytotoxicity toward NTR-expressing V79 cells with an IC(50) as low as 27 nM. They are about as active as and 3-4x more selective than 5-aziridinyl-2,4-dinitrobenzamide (CB1954). The acyclic 4-nitrobenzylphosphoramide mustard ((+/-)-7) was found to be the most active and most selective compound for activation by NTR with 170,000x selective cytotoxicity toward NTR-expressing V79 cells and an IC(50) of 0.4 nM. Compound (+/-)-7also exhibited good bystander effect compared to 5-aziridinyl-2,4-dinitrobenzamide. The low IC(50), high selectivity, and good bystander effects of nitrobenzylphosphoramide mustards in NTR-expressing cells suggest that they could be used in combination with E. coli nitroreductase in enzyme prodrug therapy.