ABSTRACT
Photocatalytic overall water splitting holds great promise for solar-to-hydrogen conversion. Maintaining charge separation is a major challenge but is key to unlocking this potential. Here we discovered a metal-organic framework (MOF) that shows suppressed charge recombination. This MOF features electronically insulated Zn2+ nodes and two chemically equivalent, yet crystallographically independent, linkers. These linkers behave as an electron donor-acceptor pair with non-overlapping band edges. Upon photoexcitation, the MOF undergoes a dynamic excited-state structural twist, inducing orbital rearrangements that forbid radiative relaxation and thereby promote a long-lived charge-separated state. As a result, the MOF achieves visible-light photocatalytic overall water splitting, in the presence of co-catalysts, with an apparent quantum efficiency of 3.09 ± 0.32% at 365 nm and shows little activity loss in 100 h of consecutive runs. Furthermore, the dynamic excited-state structural twist is also successfully extended to other photocatalysts. This strategy for suppressing charge recombination will be applicable to diverse photochemical processes beyond overall water splitting.
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Catalpol, a natural iridoid glycoside, has potential therapeutic benefits, including anti-inflammatory and neuroprotective effects. Investigating catalpol's role in angiogenesis is critical for understanding its potential therapeutic applications, particularly in diseases where modulating angiogenesis is beneficial. This study investigates catalpol's influence on angiogenesis and its mechanisms, combining network pharmacology and in vitro experiments. The target genes corresponding to the catalpol were analyzed by SwissTargetPrediction. Then angiogenesis-related targets were acquired from databases like GeneCards. Subsequently, the Database for Annotation, Visualization and Integrated Discovery was employed for Gene Ontology and pathway analysis, while Cytoscape visualized protein interactions. The effect of catalpol on viability and angiogenesis of HUVECs was further examined using Cell Counting Kit-8 and angiogenesis assays. RT-qPCR and western blot were applied to check the expression of angiogenesis-related proteins. Totally, 312 target genes of catalpol and 823 angiogenesis-related targets were obtained with 56 common targets leading to PPI network analysis, highlighting hub genes (AKT1, EGFR, STAT3, MAPK3, and CASP3). These hub genes were mainly enriched in lipid and atherosclerosis pathway and EGFR-related pathway. The in vitro experimental results showed that catalpol achieved a concentration-dependent increase in HUVECs viability. Catalpol also promoted the migration and angiogenesis of HUVECs and up-regulated the expression of EGFR. EGFR knockdown inhibited the effect of catalpol on HUVECs. Catalpol promotes angiogenesis in HUVECs by upregulating EGFR and angiogenesis-related proteins, indicating its potential therapeutic application in vascular-related diseases.
Subject(s)
Human Umbilical Vein Endothelial Cells , Iridoid Glucosides , Network Pharmacology , Humans , Iridoid Glucosides/pharmacology , Human Umbilical Vein Endothelial Cells/drug effects , Human Umbilical Vein Endothelial Cells/metabolism , Cell Survival/drug effects , Protein Interaction Maps/drug effects , ErbB Receptors/metabolism , ErbB Receptors/genetics , Signal Transduction/drug effects , Neovascularization, Physiologic/drug effects , Cell Movement/drug effects , AngiogenesisABSTRACT
Background and Aims: Age-related mosaic chromosomal alterations (mCAs) detected from genotyping of blood-derived DNA are structural somatic variants that indicate clonal hematopoiesis. This study aimed to investigate whether mCAs contribute to the risk of cirrhosis and modify the effect of a polygenic risk score (PRS) on cirrhosis risk prediction. Methods: mCA call sets of individuals with European ancestry were obtained from the UK Biobank. The PRS was constructed based on 12 susceptible single-nucleotide polymorphisms for cirrhosis. Cox proportional hazard models were applied to evaluate the associations between mCAs and cirrhosis risk. Results: Among 448,645 individuals with a median follow-up of 12.5 years, we identified 2,681 cases of cirrhosis, 1,775 cases of compensated cirrhosis, and 1,706 cases of decompensated cirrhosis. Compared to non-carriers, individuals with copy-neutral loss of heterozygosity mCAs had a significantly increased risk of cirrhosis (hazard ratio (HR) 1.42, 95% confidence interval (CI) 1.12-1.81). This risk was higher in patients with expanded cell fractions of mCAs (cell fractions ≥10% vs. cell fractions <10%), especially for the risk of decompensated cirrhosis (HR 2.03 [95% CI 1.09-3.78] vs. 1.14 [0.80-1.64]). In comparison to non-carriers of mCAs with low genetic risk, individuals with expanded copy-neutral loss of heterozygosity and high genetic risk showed the highest cirrhosis risk (HR 5.39 [95% CI 2.41-12.07]). Conclusions: The presence of mCAs is associated with increased susceptibility to cirrhosis risk and could be combined with PRS for personalized cirrhosis risk stratification.
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BACKGROUND: The aim of this study was to explore the associations of serum remnant cholesterol (RC) levels with the progression and regression of metabolic dysfunction-associated steatotic liver disease (MASLD) in Chinese adults. METHODS: We conducted a cross-sectional study in 13,903 individuals who underwent transient elastography tests (cohort 1) and a longitudinal study in 17,752 individuals who underwent at least two health check-up exams with abdominal ultrasound (cohort 2). Anthropometric and biochemical parameters were collected. Serum RC levels were calculated. Noninvasive fibrosis indices such as FIB-4 were evaluated in cohort 2. RESULTS: In cohort 1, serum RC levels were positively and independently associated with the severity of hepatic steatosis and liver fibrosis according to logistic regression analysis. In cohort 2, baseline serum RC levels were increased in participants with the incidence of MASLD and decreased in participants with the regression of MASLD during the follow-up period. Baseline serum RC levels were independently associated with an increased risk of development and a decreased likelihood of regression of MASLD: the fully adjusted hazard ratios (HR) were 2.785 (95 % CI 2.332-3.236, P < 0.001) and 2.925 (95 % CI 2.361-3.623, P < 0.001), respectively. In addition, when we used FIB-4 to evaluate liver fibrosis, baseline serum RC levels were positively correlated with the incidence of high-intermediate probability of advanced fibrosis. However, we did not find an association between serum RC levels and the regression of liver fibrosis. CONCLUSION: Serum RC levels are independently correlated with the progression and regression of MASLD in Chinese adults, suggesting that RC may participate in the pathophysiological process of MASLD.
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Shandong province, located in the Lower Yellow River, is one of the birthplaces of ancient Chinese civilization. However, the comprehensive genetic histories of this region have remained largely unknown until now due to a lack of ancient human genomes. Here, we present 21 ancient genomes from Shandong dating from the Warring States period to the Jin-Yuan Dynasties. Unlike the early Neolithic samples from Shandong, the historical samples are most closely related to post-Late Neolithic populations of the Middle Yellow River Basin, suggesting a population turnover in Shandong from the Neolithic Age to the Historical era. In addition, we detect a close genetic affinity between the historical samples in Shandong and present-day Han Chinese, showing long-term genetic stability in Han Chinese at least since the Warring States period.
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The response of Hypoxia Inducible Gene Domain (HIGD) proteins to hypoxia plays a crucial role in plant development. However, the research on this gene family in soybean has been lacking. In this study, we aimed to identify and comprehensively analyze soybean HIGD genes using the Glycine max genome database. As a result, six GmHIGD genes were successfully identified, and their phylogeny, gene structures, and putative conserved motifs were analyzed in comparison to Arabidopsis and rice. Collinearity analysis indicated that the HIGD gene family in soybean has expanded to some extent when compared to Arabidopsis. Additionally, the cis-elements in the promoter regions of GmHIGD and the transcription factors potentially binding to these regions were identified. All GmHIGD genes showed specific responsiveness to submergence and hypoxic stresses. Expression profiling through quantitative real-time PCR revealed that these genes were significantly induced by PEG treatment in root tissue. Co-expressed genes of GmHIGD were primarily associated with oxidoreductase and dioxygenase activities, as well as peroxisome function. Notably, one of GmHIGD genes, GmHIGD3 was found to be predominantly localized in mitochondria, and its overexpression in Arabidopsis led to a significantly reduction in catalase activity compared to wild-type plants. These results bring new insights into the functional role of GmHIGD in terms of subcellular localization and the regulation of oxidoreductase activity.
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The surge in face mask use due to COVID-19 has raised concerns about micro(nano)plastics (MNPs) from masks. Herein, focusing on fabric structure and polymer composition, we investigated MNP generation characteristics, mechanisms, and potential risks of surgical polypropylene (PP) and fashionable polyurethane (PU) masks during their wearing and photoaging based on stereomicroscope, µ-Fourier transform infrared spectroscopy (µ-FTIR), and scanning electron microscope (SEM) techniques. Compared with new PP and PU masks (66 ± 16 MPs/PP-mask, 163 ± 83 MPs/PU-mask), single- and multiple-used masks exhibited remarkably increased MP type and abundance (600-1867 MPs/PP-mask, 607-2167 MPs/PU-mask). Disinfection exacerbated endogenous MP generation in masks, with washing (416 MPs/PP-mask, 30,708 MPs/PU-mask) being the most prominent compared to autoclaving (219 MPs/PP-mask, 553 MPs/PU-mask) and alcohol spray (162 MPs/PP-mask, 18,333 MPs/PU-mask). Photoaging led to massive generation of MPs (8.8 × 104-3.7 × 105 MPs/PP-layer, 1.0 × 105 MPs/PU-layer) and NPs (5.2 × 109-3.6 × 1013 NPs/PP-layer, 3.5 × 1012 NPs/PU-layer) from masks, presenting highly fabric structure-dependent aging modes as "fragmentation" for fine fiber-structure PP mask and "erosion" for 3D mesh-structure PU mask. The MNPs derived from PP/PU mask caused significant deformities of Zebrafish (Danio rerio) larvae. These findings underscore the potential adverse effects of masks on humans and aquatic organisms, advocating to enhance proper use and rational disposal for masks.
Subject(s)
COVID-19 , Masks , Polypropylenes , Polyurethanes , Textiles , Polypropylenes/chemistry , COVID-19/prevention & control , Polyurethanes/chemistry , Humans , Textiles/analysis , Animals , SARS-CoV-2 , Polymers/chemistry , Microplastics/toxicity , Zebrafish , Equipment Contamination/prevention & controlABSTRACT
Face masks have emerged as a significant source of microplastics (MPs) under the influence of biotic and abiotic interactions. However, the combined effects of abiotic photoaging and biofilm-loading on mask-derived MPs as carriers of metal ions are not clear. We investigated the Pb(â ¡) adsorption onto polypropylene (PP) and polyurethane (PU) mask-derived MPs treated by photoaging, biofilm-loading, and both combinations, evaluating the composite risks. PU mask-derived MPs (1.157.47 mg/g) exhibited greater Pb(â ¡) adsorption capacity than PP mask-derived MPs (0.842.08 mg/g) because of the presence of intrinsic carbonyl functional groups. Photoaging (30.5%, 88.4%), biofilm-loading (110.7%, 87.1%), and both combinations (146.7%, 547.0%) of PP and PU masks enhanced Pb(â ¡) adsorption compared to virgin mask-derived MPs due to the increase of oxygen-containing functional groups. High-throughput sequencing indicated that the structural morphology and chemical composition of masks significantly affected the microbial community. Adsorption mechanisms involved electrostatic force and surface complexation. A combination of photoaging and biofilms increased the ecological risk index of mask-derived MPs in freshwater, showing the risk level to be high (PP mask) and very high (PU mask). This research highlights the crucial role of photoaging combined with biofilms in controlling metal ion adsorption onto mask-derived MPs, thereby increasing the composite risks.
Subject(s)
Biofilms , Lead , Microplastics , Polypropylenes , Polyurethanes , Adsorption , Lead/chemistry , Polyurethanes/chemistry , Polypropylenes/chemistry , Microplastics/chemistry , Microplastics/toxicity , Water Pollutants, Chemical/chemistry , MasksABSTRACT
Vascular remodeling is a dynamic process involving cellular and molecular changes, including cell proliferation, migration, apoptosis and extracellular matrix (ECM) synthesis or degradation, which disrupt the homeostasis of endothelial cells (ECs) and vascular smooth muscle cells (VSMCs). Cigarette smoke exposure (CSE) is thought to promote vascular remodeling, but the components are complex and the mechanisms are unclear. In this review, we overview the progression of major components of cigarette smoke (CS), such as nicotine and acrolein, involved in vascular remodeling in terms of ECs injury, VSMCs proliferation, migration, apoptosis, and ECM disruption. The aim was to elucidate the effects of different components of CS on different cells of the vascular system, to discover the relevance of their actions, and to provide new references for future studies.
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Timely adjustments of antibiotic and corticosteroid treatments are vital for patients with diffuse parenchymal lung diseases (DPLDs). In this study, 41 DPLD patients with negative metagenomic next-generation sequencing (mNGS) results who were responsive to corticosteroids were enrolled. Among these patients, about 26.8% suffered from drug-induced DPLD, while 9.8% presented autoimmune-related DPLD. Following the report of the negative mNGS results, in 34 patients with complete antibiotics administration profiles, 79.4% (27/34) patients discontinued antibiotics after receiving negative mNGS results. Moreover, 70.7% (29/41) patients began or increased the administration of corticosteroid upon receipt of negative mNGS results. In the microbiota analysis, Staphylococcus and Stenotrophomonas showed higher detection rates in patients with oxygenation index (OI) below 300, while Escherichia and Stenotrophomonas had higher abundance in patients with pleural effusion. In summary, our findings demonstrated the clinical significance of mNGS in assisting the antibiotic and corticosteroid treatment adjustments in corticosteroid-responsive DPLD. Lung microbiota may imply the severity of the disease.
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Estimating the impact of pesticide residue bioaccessibility in fruits on dietary exposure is a complex task in human health risk assessment. This research investigated the bioaccessibility of ten commonly used and detected pesticides in bananas and mangoes, as well as the factors influencing it, using an in vitro model. The highest bioaccessibility was observed at pH levels of 2.5 and 6.5 in the gastric and intestinal stages, respectively. Bioaccessibility decreased significantly with increasing solid/liquid ratios for most pesticides. The consumption of protein and four dietary components (carbohydrates, protein, lipids, and dietary fiber) could significantly reduce pesticide bioaccessibility by 9.89-48.32% (p < 0.05). Bioaccessibility in oral and gastric stages among four populations followed the order of adults/the elderly > children > infants, due to decreasing concentrations of α-amylase and pepsin. Pesticides in bananas generally exhibited a higher bioaccessibility (18.65-82.97%) compared to that in mangoes (11.68-87.57%). Bioaccessibility showed a negative correlation with the Log P values of the target pesticide, while no clear relationship was found between bioaccessibility and initial pesticide concentrations. Incorporating bioaccessible pesticide concentrations into risk assessments could lower dietary risk estimates by 11.85-79.57%. Assessing human exposure to pesticides based on bioaccessibility would greatly improve the accuracy of the risk assessment.
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Background: Severe fever with thrombocytopenia syndrome (SFTS) is an emerging epidemic infectious disease with high mortality rate. This study aimed to investigate the association of red blood cell distribution width (RDW) and mortality risk in hospitalized SFTS patients. Methods: Clinical data of SFTS patients was retrospectively collected from three hospitals between October 2010 and August 2022. Cox proportional hazards model was used to identity the risk factors for fatal outcome. The predictive value of RDW for fatal outcome was evaluated by the receiver operating characteristic (ROC) analysis and Kaplan-Meier methods. Results: Of 292 patients, the median age was 61.5 years. Non-survivors showed higher RDW value than survivors (13.6% vs.13.0%, P < 0.001). The mortality rate was 44.8% in patients with elevated RDW compared to 18.4% of patients with normal RDW, with a relative risk (RR) of 2.439. Elevated RDW was an independent risk factor of mortality (hazards ratio: 1.167, P = 0.019). Patients with elevated RDW had a higher cumulative mortality than patients with normal RDW. The area under the ROC curve (AUC) of RDW for the prediction of mortality was 0.690 (P < 0.001). Conclusion: Elevated RDW was associated with higher mortality risk for patients hospitalized for SFTS. RDW may be helpful for risk stratification in SFTS patients.
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Alteration in lipid metabolism is recognized as a hallmark feature of colorectal cancer (CRC). Protein S-palmitoylation plays a critical role in many different cellular processes including protein-lipid interaction. Zinc Finger DHHC-Type Containing 1 (ZDHHC1, also known as ZNF377) belongs to the palmitoyl-transferase ZDHHC family, and is a potential tumor suppressor. However, our knowledge of the functional roles of ZDHHC1 in CRC is limited. We discovered that ZDHHC1 expression was downregulated in CRC tissues and that low levels of ZDHHC1 were associated with unfavorable prognosis. Functional studies showed that ZDHHC1 inhibited CRC cell proliferation and invasion in vitro and in vivo. We also found that lipase G (LIPG) is negatively regulated by ZDHHC1 and plays a key role in CRC cell growth through lipid storage. Additionally, we demonstrated that ZDHHC1 functions as a IGF2BP1-palmitoylating enzyme that induces S-palmitoylation at IGF2BP1-C337, which results in downregulated LIPG expression via m6A modification. Mechanistic investigations revealed that the ZDHHC1/IGF2BP1/LIPG signaling axis is associated with inhibition of CRC cell growth. Our study uncovers the potential role of ZDHHC1 in CRC, including inhibition of CRC growth by reducing the stability of LIPG mRNA in an m6A dependent-manner by palmitoylation of IGF2BP1.
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Objective: This study aimed to explore the global and future research trends in acupuncture interventions for stroke between 2000 and 2022 using bibliometric analysis. Method: A bibliometric analysis of literature from 2000 to 2022 in the Web of Science Core Collection was conducted in this study. The analysis utilized CiteSpace, VOSviewer, and Scimago Graphica software to identify the major contributors to publications, including authors, countries, institutions, journals, references, and keywords. Results: The bibliometric analysis yielded a total of 860 publications. There was a gradual increase in the number of publications over the study period. China published the most articles. Evidence-Based Complementary and Alternative Medicine was the journal with the greatest number of publications. The most frequently used keywords were "acupuncture," "stroke," and "electroacupuncture." Conclusion: These analysis uncovers the research trends in acupuncture for stroke spanning 2000 to 2022 and points to prospective research frontiers. This study provides a deeper and more thorough understanding of the connotations of acupuncture for stroke and guidance and support for future research in this field.
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Unilateral Tracheobronchial foreign body (TFB) present a common clinical disease, whereas bilateral TFB is a rare and acute condition associated with high mortality rates. This case study discusses a pediatric patient hospitalized due to respiratory distress following accidental ingestion of peanut kernels. A plain chest CT scan revealed obstructive emphysema in the right main bronchus and a foreign body at the opening of the left main bronchus. Surgical removal of the bilateral TFB under extracorporeal circulation resulted in a successful postoperative recovery, leading to discharge on the 9th day. A comprehensive literature search was conducted across databases including PubMed, Web of Science, EMBASE, Cochrane Library, and CNKI, spanning publications from January 2014 to October 2023, utilizing keywords "bronchial foreign body" and "Peanut". After deduplication and relevance screening, 9 pertinent literature sources were included. The objective of this study is to enhance clinical practitioners' understanding of TFB management and improve diagnostic and treatment capabilities through analysis of age of onset, clinical manifestations, diagnosis, and treatment approaches in critically ill pediatric patients.
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Here, we report the discovery of two viruses associated with a disease characterized by severe diarrhea on a large-scale goat farm in Jilin province. Electron Microscopy observations revealed two kinds of virus particles with the sizes of 150-210 nm and 20-30 nm, respectively. Detection of 276 fecal specimens from the diseased herds showed the extensive infection of peste des petits ruminants virus (63.77%, 176/276) and caprine enterovirus (76.81%, 212/276), with a co-infection rate of 57.97% (160/276). These results were partially validated with RT-PCR, where all five PPRV-positive and CEV-positive specimens yielded the expected size of fragments, respectively, while no fragments were amplified from PPRV-negative and CEV-negative specimens. Moreover, corresponding PPRV and CEV fragments were amplified in PPRV and CEV double-positive specimens. Histopathological examinations revealed severe microscopic lesions such as degeneration, necrosis, and detachment of epithelial cells in the bronchioles and intestine. An immunohistochemistry assay detected PPRV antigens in bronchioles, cartilage tissue, intestine, and lymph nodes. Simultaneously, caprine enterovirus antigens were detected in lung, kidney, and intestinal tissues from the goats infected by the peste des petits ruminants virus. These results demonstrated the co-infection of peste des petits ruminants virus with caprine enterovirus in goats, revealing the tissue tropism for these two viruses, thus laying a basis for the future diagnosis, prevention, and epidemiological survey for these two virus infections.
Subject(s)
Coinfection , Diarrhea , Enterovirus Infections , Goat Diseases , Goats , Peste-des-Petits-Ruminants , Peste-des-petits-ruminants virus , Animals , Peste-des-Petits-Ruminants/virology , Peste-des-Petits-Ruminants/epidemiology , Peste-des-Petits-Ruminants/pathology , Peste-des-petits-ruminants virus/isolation & purification , Peste-des-petits-ruminants virus/genetics , Goat Diseases/virology , Goat Diseases/epidemiology , China/epidemiology , Coinfection/veterinary , Coinfection/virology , Coinfection/epidemiology , Enterovirus Infections/veterinary , Enterovirus Infections/virology , Enterovirus Infections/epidemiology , Diarrhea/virology , Diarrhea/veterinary , Diarrhea/epidemiology , Enterovirus/isolation & purification , Enterovirus/genetics , Enterovirus/classification , Feces/virology , PhylogenyABSTRACT
Lithium (Li) is an important resource that drives sustainable mobility and renewable energy. Its demand is projected to continue to increase in the coming decades. However, the risk of Li pollution has also emerged as a global concern. Here, we investigated the pollution characteristics, sources, exposure levels, and associated health risks of Li in the Jinjiang River basin, the largest area for Li2CO3 production in China. Our results revealed the dominant role of Li extraction activities in the pollution of the river, with over 95% of dissolved Li in downstream river water being emitted from this source. Moreover, the Li concentration in aquatic plants (i.e., water hyacinth) and animals (i.e., fish) significantly increased from upstream to downstream areas, indicating a significant risk to local aquatic ecosystems. More importantly, our study found that local residents were suffering potential chronic noncarcinogenic health risks primarily from consuming contaminated water and vegetables. We also investigated the pollution characteristics of associated elements present in Li ores (e.g., Rb, Cs, Ni, and F-). By uncovering the remarkable impact of Li extraction activities on the Li content in ecosystems for the first time, our study emphasizes the importance of evaluating Li pollution from Li-related industrial activities, including mining, extraction, and recovery.
Subject(s)
Lithium , Lithium/analysis , China , Water Pollutants, Chemical/analysis , Humans , Rivers/chemistry , Risk Assessment , Environmental Monitoring , AnimalsABSTRACT
Peptides are widely used as natural bio-small molecules because of their various pharmacological activities such as enhancing immunity, promoting wound healing, and improving inflammation. Alcoholic heart injury has become one of the major health problems worldwide, and alcohol consumption is now the main cause of alcoholic cardiomyopathy. In this study, deer heart peptides were extracted from deer hearts by enzymatic digestion and the antioxidant activity of deer heart peptides extracted at different times was evaluated by three in vitro antioxidant methods, and the active peptide with the best enzymatic effect has been selected for in vivo animal experiments. The anti-inflammatory and antioxidant properties of deer heart enzymatic extracts were evaluated in in vivo experiments in mice. In this study, mice were orally gavaged with white wine (12 mL/kg body weight) to induce a mouse model of cardiac injury, while mice were orally administered a single dose of 100 mg/kg/bw and 200 mg/kg/bw of deer heart enzyme digest and were examined for body weight, dietary intake, water intake, and coat gloss, as well as for general behaviors, adverse effects, and mortality. Histology, serum, anti-inflammatory factors, and oxidative stress parameters were subsequently assessed. In all modeled mice, no four-way or any significant behavioral changes were observed in all groups, but in the modeled group, mice showed weight loss, decreased diet and water intake, and decreased cardiac index. For in vivo tests, the extract inhibited the anti-inflammatory activity with a significant decrease in inflammatory factors of TNF-α, IL-6, and IL-1ß in cardiac tissues, a significant increase in serum levels of both CAT and SOD, an increase in MDA content, and a remarkable increase in the level of the marker CK in the cardiac myocardial enzyme profile. Significant improvement in myocardial disorders by deer heart peptide could be observed from heart tissue sections. The present study emphasizes the anti-inflammatory and antioxidant activity of deer heart peptide, an enzymatic digest of deer heart, which provides empirical as well as supportive role for the anti-inflammatory properties of traditional medicine.
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In this Letter, we present a robust, wide-range, and precise monitoring scheme for transmitter (Tx) impairments in coherent digital subcarrier multiplexing (DSCM) systems. The proposed scheme employs frequency-domain pilot tones (FPTs) to compensate for frequency offset (FO), polarization aliasing, and carrier phase noise, thus isolating Tx impairments from channel distortions. It then implements 4 × 4 real-valued MIMO to compensate for Tx impairments by equalizing symmetric subcarriers. Tx impairment monitoring is derived from the equalizer coefficients. By considering the phase shift caused by Tx impairments, a wide-range and precise monitoring of Tx impairments including IQ skew, IQ phase, and gain imbalances is achieved. We experimentally validated our approach using a 48-GBaud, four-subcarrier, dual-polarization coherent DSCM system. The results confirm the method's capability for a wide-range, robust, and precise Tx impairment monitoring in coherent DSCM systems, maintaining performance even in the presence of ultra-fast polarization variation.
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Soil contamination by petroleum, including crude oil from various sources, is increasingly becoming a pressing global environmental concern, necessitating the exploration of innovative and sustainable remediation strategies. The present field-scale study developed a simple, cost-effective microbial remediation process for treating petroleum-contaminated soil. The soil treatment involves adding microbial activators to stimulate indigenous petroleum-degrading microorganisms, thereby enhancing the total petroleum hydrocarbons (TPH) degradation rate. The formulated microbial activator provided a growth-enhancing complex of nitrogen and phosphorus, trace elements, growth factors, biosurfactants, and soil pH regulators. The field trials, involving two 500 m3 soil samples with the initial TPH content of 5.01% and 2.15%, were reduced to 0.41% and 0.02% in 50 days, respectively, reaching the national standard for cultivated land category II. The treatment period was notably shorter than the commonly used composting and bioaugmentation methods (typically from 8 to 12 weeks). The results indicated that the activator could stimulate the functional microorganisms in the soil and reduce the phytotoxicity of the contaminated soil. After 40 days of treatment, the germination rate of rye seeds increased from 20 to 90%, indicating that the microbial activator could be effectively used for rapid on-site remediation of oil-contaminated soils.