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Between 2000 and 2020, global wildfires contributed to approximately 7.32 billion metric tons of carbon dioxide (CO2) emissions, accounting for about 18.5% of CO2 emissions released from fossil fuels. Forest fires alone contributed to around 20% of these wildfire emissions, approximately 1.5 billion metric tons of CO2. Due to climate change and human activities, carbon emissions from forest fires are on the rise. For example, the 2023 Canadian fires have emitted 1.268 billion metric tons of CO2 up to August 29th. Despite the simultaneous increase in forest area and volume, the frequency and extent of forest fires have significantly decreased in China since 2010, which has made a significant contribution to global carbon emission reduction. Given forest fires have become a significant global carbon emission source, a comprehensive, objective, and fair carbon emission monitoring and accounting system that considers carbon emissions from both human activities and forest fires should be established. At the same time, effective measures should be taken to reduce the occurrence frequency and intensity of wildfires to lower carbon emissions from forest fires. To address the challenges of predicting and preventing extreme forest fire behavior, it is essential to develop a forest fire risk identification, early warning, prediction, and prevention technology system. Additionally, research should be devoted to carbon emissions from wildfires, aiming to establish a more scientific, comprehensive, and domestically controllable carbon accounting system. [ABSTRACT FROM AUTHOR]

The paper formulates a SEIR model with time delay effect to explain the influence of media reports on diseases. Firstly, the basic reproduction number of the model is determined by the method of next generation matrix. The existence and the global stability of the equilibrium point are discussed. Secondly, sufficient conditions of Hopf bifurcation of the model are given. Finally, by numerical simulation, we prove the correctness of the theories. [ABSTRACT FROM AUTHOR]

Cellulose acetate (CA) is a significant biobased sustainable polymer with environmentally friendly, renewable, easily degradable and biocompatible features, which plays a crucial role in various fields. For example, it is widely used in the manufacture of a wide range of polymer materials, such as textiles, membranes, and cigarette filters. However, the narrow processing temperature range of CA polymers, due to the proximity between the viscous flow temperature (Tf) and decomposition temperature (Td), leads to difficulties in melt processing and limits the development of mechanically strengthened CA materials. Introducing crosslinking agents to establish covalent crosslinked networks is an effective approach to enhance the mechanical properties of CA materials, which is essential for the development of high-performance CA materials. However the covalent crosslinked network also restricts the re-processability of CA materials. In this work, a small amount of poly(vinyl alcohol) (PVA) and boric acid (BA) were employed to construct a novel dynamic crosslinked CABA-PVA material based on reversible covalent borate ester bond via solution processing under mild conditions. This method is simple, efficient, and maintains the appearance of CA materials unchanged. The results demonstrated that the introduction of the above reversible crosslinked polymer network enhanced many properties of CA materials, such as thermal stability, rheological property, creeping resistance and tensile strength, compared with unmodified cellulose acetate. Furthermore, due to the establishment of a dynamic crosslinked network, the CA materials exhibited good re-processability. They could be recycled three times without losing transparency and mechanical strength. [ABSTRACT FROM AUTHOR]

Chinese Foundation for Hepatitis Prevention and Control; Chinese Society of Infectious Diseases, Chinese Medical Association; Chinese Society of Hepatology, Chinese Medical Association. [ABSTRACT FROM AUTHOR]

AIM: To investigate whether asymmetric dimethylarginine （ADMA）, an endogenous nitric oxide synthase （NOS） inhibitor, induces early kidney injury in mice through ferroptosis. METHODS: Sixteen 8-week-old SPF C57BL/6 male mice were randomly assigned to control group （n=8） and experimental group （n=8）. The experimental mice were orally administered with ADMA （60 mg·kg-1·d-1） daily for 16 weeks, while the control mice were orally administered with an equal volume of saline daily. After the treatment, glucose tolerance and insulin tolerance were measured in both groups. Serum samples were collected to measure ADMA levels, total cholesterol （TC）, triglycerides （TG）, and high-density lipoprotein cholesterol （HDL-C） levels. Blood urea nitrogen （BUN） levels were also determined. Kidney tissue samples were collected to assess pathological morphology, interleukin-6 （IL-6） and IL-1β levels, iron content, nitric oxide （NO） levels, malondialdehyde （MDA） levels, superoxide dismutase （SOD） activity, and the protein expression of endothelial NOS （eNOS）, inducible NOS （iNOS）, glutathione peroxidase 4 （GPX4）, Bcl2, Bax and caspase-1. RESULTS: Compared with the control group, the ADMA-treated mice showed impaired glucose tolerance and insulin sensitivity, indicating abnormal glucose metabolism. Serum TG and TC levels were elevated （P<0. 01）, while HDL-C level was decreased （P<0. 05）, indicating abnormal lipid metabolism. Additionally, ADMA directly induced early renal injury in mice resembling chronic kidney failure, characterized by glomerular hypertrophy, glomerular mesangial cell hypertrophy and increased BUN levels （P<0. 01）, as well as significantly elevated levels of pro-inflammatory cytokines IL-6 and IL-1β （P<0. 01）. Moreover, the ADMA-treated mice exhibited increased ADMA levels in kidney tissue （P<0. 01）, reduced expression of eNOS protein and total NO levels, but significantly increased expression of iNOS protein （P<0. 01）. Furthermore, kidney tissue analysis revealed iron overload, increased MDA levels, decreased SOD activity, decreased expression of GPX4 protein and anti-apoptotic protein Bcl2 （P<0. 01）, and increased expression of apoptosis markers Bax and caspase-1 proteins （P<0. 05 or P<0. 01）. CONCLUSION: ADMA may induce early kidney injury in mice through ferropotosis. [ABSTRACT FROM AUTHOR]

A large number of wastes with high organic matter, high oil and high moisture content are produced in the world every year. If not properly disposed of, it will pose a great threat to the ecological environment and human health. The harmless treatment and resource utilization of these organic wastes are important means to solve this problem. At present, insect biotransformation technology represented by the black soldier fly is one of the most potential strategies to deal with organic waste pollution. This technology has low energy consumption and low emissions, and has good social, ecological and economic benefits, which will lay a solid foundation for the construction of a harmonious ecological system. This paper describes the biological characteristics of the black soldier fly, the biological transformation of organic wastes such as kitchen waste, livestock and poultry manure, the synergistic effect of microorganisms in this process and the utilization of larval resources, and analyzes the development prospect of the black soldier fly. [ABSTRACT FROM AUTHOR]

Objective The aim is to study the application of calcium-based dry desulfurizer in the field of flue gas desulfurization, and give full play to the advantages of low cost, good desulfurization performance and environmental friendliness of calcium-based desulfurizer, so as to achieve the up-to-standard emission of SO2 in flue gas. Methods The physical and chemical properties of the prepared calcium-based desulfurizer were characterized by XRD, BET, FTIR and XPS. Additionally, simulating sulfur-containing waste gas, the effects of SO2 content, reaction temperature, O2 content and volume space velocity on the desulfurization performance of calciumbased dry desulfurizer were investigated by a fixed bed reactor. Results The prepared calcium-based desulfurizer demonstrated effective desulfurization, and its optimum operating temperature range was 220-300 ℃, which was suitable for the case that the volume fraction of SO2 in flue gas did not exceed 0.4%. The increase of O2 content produced new active sites for adsorption, which could promote desulfurization process. When the volume space velocity was in the range of 500-2 000 h−1, the sulfur capacity did not change much. Conclusions The application of calcium-based dry desulfurizer in the field of flue gas desulfurization has high efficiency and stability, which can provide reference for its wide application in the industrial field. [ABSTRACT FROM AUTHOR]

Objective To observe the changes of serum inflammatory factors, gut microbiota, and short chain fatty acids in feces of mice on a high-salt diet intragastrically administered Clostridium leptum. Methods Sixteen C57BL/6 male mice were randomly divided into the experimental group and control group. Mice in both groups were fed with a highsalt diet containing 8% NaCl for 16 weeks. Mice in the experimental group were gavaged with 2 mL Clostridium leptum sus‐ pension (109 CFU/mL) every other day, while mice in the control group were gavaged with 2 mL ultrapure water every oth‐ er day. Serum interleukin (IL) -1B, IL-6 and tumor necrosis factor-α (TNF-α) were detected by the ELISA. The fresh fe‐ cal samples were collected from mice for 16S rDNA high-throughput sequencing and short-chain fatty acids quantification. Results The serum levels of IL-1B, IL-6, and TNF-α in the experimental group were lower than those in the control group (all P<0. 05). The results of gut microbiota α-diversity and β-diversity analysis showed that the structure and diversity of gut microbiota in the experimental group significantly different from those in the control group. Compared with the control group, the relative abundance of Bacteroidetes and Proteobacteria in the experimental group increased, while the relative abundance of Firmicutes and Verrucobacteria decreased (all P<0. 05). At the species level, the Lactobacillus was significantly enriched in the experimental group, while the opportunistic pathogens such as Staphylococcus xylose and Staphylococcus lentus were significantly enriched in the control group. The concentrations of propionic acid, butyric acid and caproic acid in the experimental group were higher than those in the control group (all P<0. 05). Conclusion Clostridium leptum could reduce the levels of serum inflammatory factors, change the structure of gut microbiota and affect the metabolism of short chain fatty acids in the mice on a high-salt diet. [ABSTRACT FROM AUTHOR]

Objective In order to effectively improve the sulfur capacity and reduction reaction performance, the influence of Fe and Ce metal additives dosage and process condition on the reactivity for compound metal-oxide solid desulfurizer was studied. Methods Based on the mechanism of the oxidation adsorption and reduction regeneration reaction, the effects of the metal additives dosage, volume space velocity, reaction temperature, feed gas composition, and reducing gas type on the reaction performance were studied utilizing control variate method. Results Under the conditions of reaction temperature of 500 °C and volume space velocity of 3 000 h-1, the sulfur capacity could reach up to 24.0 wt%, and the reduction reaction time was 65 min when the dosage of Fe2O3 and Ce2O3 were 2a wt% and 3b wt%, respectively. In addition, the sulfur capacity of the solid desulfurizer could be further increased by modifying process conditions, such as reducing the volume space velocity, increasing the reaction temperature, reducing the SO2 content, or increasing the O2 content. The type of reducing gas also had a significant impact on the regeneration reaction process. Conclusion The influence of metal additives and process conditions on the reactivity of desulfurization reaction is clarified, which can provide theoretical guidance for developing and industrial applications of high-temperature regenerative solid desulfurizer. [ABSTRACT FROM AUTHOR]

BACKGROUND: Current studies have addressed the mesenchymal stem cells (MSCs) mostly from fresh human umbilical cord, but rarely from cryopreserved human umbilical cord. OBJECTIVE: To isolate MSCs from cryopreserved human umbilical cord, and to compare the biological characteristics of human umbilical cord MSCs (hUC-MSCs) harvested using several culture methods. METHODS: hUC-MSCs isolated from cryopreserved umbilical cord tissues by explants culture method were cultured in serum-containing and serum-free media. Cell morphology was observed to draw the growth curve of cells in different media. Passage 3 hUC-MSCs cultured in serum-free medium and passage 14 hUC-MSCs in serum-containing medium were selected to detect the expression of surface biomarkers by flow cytometry. Passage 3 cells in the serum-free medium were induced for adipogenic, osteogenic and chondrogenic differentiation, and differentiation marker genes were identified by qPCR. Expression of cytokines in the passage 7 cells cultured in the serum-free medium and in the culture supernatant was detected. RESULTS AND CONCLUSION: The hUC-MSCs isolated from cryopreserved human umbilical cord exhibited a spindle-shaped appearance and exuberant growth, and moreover, the cells could be expanded in serum-free medium but the cell proliferation was certainly slower than that in the serum-containing medium. Flow cytometry analysis revealed that the hUC-MSCs were positive for CD73, CD90, CD103, but negative for CD45, CD34, CD14/CD11b, CD79a/CD19, and HLA-DR. Adipogenic (PPARγ), osteogenic (Osteonectin) and chondrogenic (Collagen II) biomarker genes were highly expressed at 14-28 days of induction. Passage 7 hUC-MSC and its supernatant secreted several cytokines including granulocyte colony-stimulating factor, granulocyte-macrophage colony-stimulating factor, interferon α2, chemokine IP-10, interleukin 4, and interleukin-6. In conclusion, we could successfully isolate and expand hUC-MSCs from cryopreserved human umbilical cord tissuesBACKGROUND: Current studies have addressed the mesenchymal stem cells (MSCs) mostly from fresh human umbilical cord, but rarely from cryopreserved human umbilical cord. OBJECTIVE: To isolate MSCs from cryopreserved human umbilical cord, and to compare the biological characteristics of human umbilical cord MSCs (hUC-MSCs) harvested using several culture methods. METHODS: hUC-MSCs isolated from cryopreserved umbilical cord tissues by explants culture method were cultured in serum-containing and serum-free media. Cell morphology was observed to draw the growth curve of cells in different media. Passage 3 hUC-MSCs cultured in serum-free medium and passage 14 hUC-MSCs in serum-containing medium were selected to detect the expression of surface biomarkers by flow cytometry. Passage 3 cells in the serum-free medium were induced for adipogenic, osteogenic and chondrogenic differentiation, and differentiation marker genes were identified by qPCR. Expression of cytokines in the passage 7 cells cultured in the serum-free medium and in the culture supernatant was detected. RESULTS AND CONCLUSION: The hUC-MSCs isolated from cryopreserved human umbilical cord exhibited a spindle-shaped appearance and exuberant growth, and moreover, the cells could be expanded in serum-free medium but the cell proliferation was certainly slower than that in the serum-containing medium. Flow cytometry analysis revealed that the hUC-MSCs were positive for CD73, CD90, CD103, but negative for CD45, CD34, CD14/CD11b, CD79a/CD19, and HLA-DR. Adipogenic (PPARγ), osteogenic (Osteonectin) and chondrogenic (Collagen II) biomarker genes were highly expressed at 14-28 days of induction. Passage 7 hUC-MSC and its supernatant secreted several cytokines including granulocyte colony-stimulating factor, granulocyte-macrophage colony-stimulating factor, interferon α2, chemokine IP-10, interleukin 4, and interleukin-6. In conclusion, we could successfully isolate and expand hUC-MSCs from cryopreserved human umbilical cord tissues [ABSTRACT FROM AUTHOR]

BACKGROUND: Atherosclerosis is the pathological basis of many cardiovascular and cerebrovascular diseases. Yiqi Tongmai Fang can significantly improve atherosclerosis in patients, but the metabolic spectrum and mechanism underlying the intervention of atherosclerosis using Yiqi Tongmai Fang are still incomplete. OBJECTIVE: To explore the possible mechanism of Yiqi Tongmai Fang in the treatment of atherosclerosis. METHODS: Thirty-six male C57/B6J mice were selected, 6 of which were used as normal controls and given normal diet for 12 weeks. The remaining 30 ApoE-/- mice were randomly divided into model group, low-, medium- and high-dose Yiqi Tongmai Fang groups and atorvastatin group, with 6 mice in each group, and then were fed with high fat diet combine with intragastrical administration of sodium chloride, low-, medium- and high-dose Yiqi Tongmai Fang (0.39, 0.78, 1.56 g/kg per day) and atorvastatin (2.6 mg/kg per day), respectively. Serum and aortic tissue were collected after 12 weeks. The pathological changes of the aorta and vascular stenosis were observed by vascular histopathological section. The serum samples were analyzed by ultrahigh performance liquid chromatography-mass spectrometer for high-throughput target metabolomics, to screen different amino acids between groups. RESULTS AND CONCLUSION: In terms of morphology, vascular pathological injury and stenosis were significantly improved in the Yiqi Tongmai Fang groups compared with the model group. In terms of serum amino acid metabolism, the levels of seven amino acids were significantly changed in the Yiqi Tongmai Fang group compared with the normal control group, including the increased levels of L-Glutamic acid, L-Tyrosine, L-Aspartate, L-Lysine and L-Valine, and the decreased levels of L-Arginine and 3-methyl-L-histidine. Yiqi Tongmai Fang could regulate the levels of different amino acids and high-dose Yiqi Tongmai Fang could regulate the most metabolites. Overall, these findings indicate that Yiqi Tongmai Fang can delay the progression of atherosclerosis and its mechanism may be related to the regulation of amino acid metabolism. Moreover, high-dose Yiqi Tongmai Fang has the most significant effect. [ABSTRACT FROM AUTHOR]

Abstract：Objective To investigate the effect of high-salt diet (HSD) on cognitive function of mice and to explore whether it is related to the disorders of gut microbiota. Methods Twenty C57BL/6 male mice were randomly divided into two groups：the ND group (n=10) and the HSD group (n=10) . The mice in the ND group were fed with ordinary maintenance fodder, and the mice in the HSD group were fed with high-salt fodder. They both were treated for 16 weeks. The cognitive function of mice was tested via Y maze and novel object recognition test, respectively, and we recorded the spontaneous response rate and preference rate data. Then fecal samples were collected for the total bacterial RNA extraction and 16S rDNA V4 fragment amplification by PCR method. We analyzed the differences of microbial composition between two groups by high-throughput sequencing. The relative expression levels of synaptophysin (SYP) mRNA in the brain tissues of two groups were detected by real-time fluorescence quantitative PCR method. Results The mice in the HSD group had significantly lower rate of spontaneous reaction and preference in both Y maze and novel object recognition test, as well as lower levels of SYP expression in brain tissues as compared with those of the ND group (all P<0. 05), and there were no significant differences in OTU number or α-diversity which included four indexes, Ace, Chao1, Shannon and Simpson, rspectively, between these two groups (all P>0. 05) . In the level of phylum, there were no significant differences in the the relative abundances of Birmicutes, Bacteroidetes, Proteobacteria, or Actinobacteria between these two groups (all P> 0. 05) . In the level of species, the relative abundances of Akkermansia muciniphila, Bacillus acidifaciens and Faecalibaculum rodentium were higher, while the relative abundance of Clostridium leptum was lower in the HSD group than in the ND group (all P<0. 05. Conclusion HSD impairs cognitive function in mice, which may be related to the disorders of gut microbiota. [ABSTRACT FROM AUTHOR]

In order to accurately determine pyrazines and pyridines in saliva of tobacco smokers, a method of gas chromatography-positive chemical ionization-time of flight mass spectrometry (GC-PCI-TOF MS) was developed. The pre-treatment method of sample, chromatogphic condition and MS condition were optimized. Saliva samples were extracted with dichloromethane by vortex mixing and cleaned up by primary secondary amine (PSA), then detected by GC-PCI-TOF MS. Retention time, precise mass data of characteristic ions and fragmentation patterns of characteristic fragment ions were employed to qualitative identification, external standard method was used for quantitative determination. The results showed that: 1) The average of extraction yield of 11 pyrazines and pyridines was 97.7% when 5 mL saliva sample was extracted by dichloromethane two times. 2) The matrix effects were studied by comparing the pyrazines and pyridines peak response in matrix standard solution and matrix-free standard solution, which performed with no significance. 3) Mass number of characteristic ions measured was in good agreement with predicted value, and the error was less than 3.12×10-6. Besides, predominant molecular ion and adduct molecular ion peak were obtained in PCI mode with less fragment ions formation. The mass spectrum was simple and clear, which was easy to identify. Given the above, the accuracy of qualitative analysis for low concentrations of pyrazines and pyridines in saliva could be significantly improved. 4) The linear correlation coefficients were above 0.999 1, the limits of detection (LODs) ranged from 0.9 μg/L to 2.4 μg/L, the limits of quantitation (LOQs) ranged from 3.0 μg/L to 7.9 μg/L, and the recoveries ranged from 85% to 104% at three spiked levels. The quantitative method was proved to be high accuracy and high sensitivity. 5) The detection results of saliva of tobacco smokers showed that the main pyrazines and pyridines in smokers’ saliva were pyridine, 2-methylpyrazine and dimethylpyrazines, and the contents of pyridine and 2-methylpyrazine in smokers’ saliva was differed by cigarette type. Low concentration of trimethylpyrazine and tetramethylpyrazine were detected in specific saliva samples of tobacco smokers. 3-Ethylpyridine and 5-ethyl-2-methylpyridine were not found in experimental tobacco smokers’ saliva sample. 6) Pyrazines and pyridines’ contents in different smokers’ saliva of 6 kind cigarettes were analyzed using principal component analysis which can distinguish different types of cigarette. Further analysis indicated that there was a significant variance-(P<0.05) between the pyrazines and pyridines in saliva among the 6 different kinds of cigarette, which might be a significantly characteristic of cigarette type. The method is simple, rapid and accuracy, which is superior in analyzing low level of pyrazines and pyridines in saliva of tobacco smokers and similar complex matrix. The study result will also offer accurate and scientific reference on cigarette product development. [ABSTRACT FROM AUTHOR]

In China, hepatitis B virus (HBV) infection remains a great threat to public health. Preventing the mother-to-child transmission (MTCT) of HBV is the main method to reduce the harm and disease burden caused by viral hepatitis in China. Recent studies have demonstrated that antiviral therapy with tenofovir disoproxil fumarate (TDF) during late pregnancy for mothers can further reduce MTCT of HBV. Meanwhile, Chinese Foundation for Hepatitis Prevention and Control launched the Hepatitis B Shield Project on July 25, 2015. This project aims to further reduce or even eliminate MTCT of HBV by means of standard management of pregnant women with HBV via a mobile-health application. At present, China has made great achievements in fighting against HBV. We believe that the remarkable findings of such studies and the launch of the Chinese Shield Project will make the Chinese dream-HBV-free generation come true in the near future. [ABSTRACT FROM AUTHOR]