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Growing evidences showed that heavy metals exposure may be associated with metabolic diseases. Nevertheless, the mechanism underlying arsenic (As) exposure and metabolic syndrome (MetS) risk has not been fully elucidated. So we aimed to prospectively investigate the role of serum uric acid (SUA) on the association between blood As exposure and incident MetS. A sample of 1045 older participants in a community in China was analyzed. We determined As at baseline and SUA concentration at follow-up in the Yiwu Elderly Cohort. MetS events were defined according to the criteria of the International Diabetes Federation (IDF). Generalized linear model with log-binominal regression model was applied to estimate the association of As with incident MetS. To investigate the role of SUA in the association between As and MetS, a mediation analysis was conducted. In the fully adjusted log-binominal model, per interquartile range increment of As, the risk of MetS increased 1.25-fold. Compared with the lowest quartile of As, the adjusted relative risk (RR) of MetS in the highest quartile was 1.42 (95% confidence interval, CI: 1.03, 2.00). Additionally, blood As was positively associated with SUA, while SUA had significant association with MetS risk. Further mediation analysis demonstrated that the association of As and MetS risk was mediated by SUA, with the proportion of 15.7%. Our study found higher As was remarkably associated with the elevated risk of MetS in the Chinese older adults population. Mediation analysis indicated that SUA might be a mediator in the association between As exposure and MetS.
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Arsênio , Exposição Ambiental , Síndrome Metabólica , Ácido Úrico , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Arsênio/sangue , Arsênio/toxicidade , China/epidemiologia , População do Leste Asiático , Exposição Ambiental/efeitos adversos , Síndrome Metabólica/epidemiologia , Síndrome Metabólica/induzido quimicamente , Síndrome Metabólica/sangue , Ácido Úrico/sangueRESUMO
Background: Urachal carcinoma (UrC) is a rare malignancy with no known specific early symptoms. It is often diagnosed at advanced stages and is associated with poor prognosis. Case presentation: This study presents a rare case of urachal adenocarcinoma (UrAC) invading the bladder and vagina in a female patient. Initially, the patient was misdiagnosed as having a primary cervical adenocarcinoma 2.5 years prior. Subsequently, anterior pelvic exenteration and bilateral ureterocutaneostomies were performed. Twenty months after the first surgery, the patient was diagnosed with rectal metastasis and received gemcitabine chemotherapy. After achieving a stable disease state, the patient underwent laparoscopic ultralow rectal anterior resection, ultralow anastomosis of the sigmoid colon and rectum, prophylactic transverse colostomy, and right common iliac and external iliac lymph node dissection. The patient then received a cycle of postoperative chemotherapy with oxaliplatin and capecitabine; however, treatment was stopped due to adverse reactions. The patient continues to receive regular follow-ups, and her general condition is good. Conclusions: UrC is rare, and preoperative differential diagnosis is difficult. This is the first report of UrC being misdiagnosed as cervical cancer. The presented case highlights the importance of accurate histopathological examination and comprehensive analysis. Anterior pelvic exenteration was also identified as a potentially effective treatment strategy for patients with local pelvic recurrence of UrC, although further investigation is required.
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Background: Lynch syndrome (LS) is an autosomal dominant inherited disorder caused by mutations in mismatch repair genes. Genetic counseling is crucial for the prevention and treatment of LS, as individuals with these mutations have an increased lifetime risk of developing multiple cancers. MutS Homolog 2 (MSH2) is a protein-coding gene that plays a key role in LS. A significant number of LS cases are linked to harmful heterozygous mutations in the MSH2 gene. Case Presentation: The proband was a 50-year-old endometrial dedifferentiated carcinoma patient with a dMMR/MSI-H tumor negative for MSH2/MSH6 expression by immunohistochemistry. Genetic counseling and tumor gene testing were conducted using next-generation sequencing (NGS) technology, which revealed a previously unknown germline MSH2 gene nonsense mutation NM_000251.2:exon2.354T>A (p.Y118*), leading to a diagnosis of LS. Further analysis of this variant in five family members of the patient confirmed its presence in all individuals, with one family member being diagnosed with colorectal cancer (CRC) at the age of 43. The proband received postoperative chemoradiotherapy and achieved a disease-free survival of 2 years, with ongoing follow-up. Conclusion: This study provides evidence that the MSH2 nonsense mutation c.354T>A is a highly likely pathogenic mutation and is responsible for typical LS-associated endometrial carcinoma. It emphasizes the importance of genetic counseling for proband family members to facilitate early diagnosis of LS-related carcinoma.
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OBJECTIVE: To investigate the prognostic significance of molecular classification on treatment outcomes of fertility-sparing treatment (FST) in early-stage endometrial cancer (EC), and its potential in optimizing fertility-sparing management. METHODS: Patients with early-stage EC who received FST with ProMisE classification were investigated. Oncological and reproductive outcomes were compared across four molecular subtypes. Factors influencing complete response (CR) were analyzed. RESULTS: Among 116 molecularly classified patients, 80 were evaluated for therapeutic effects, including 64 (80.0 %) p53wt, 7 (8.7 %) MMR-D, 5 (6.3 %) POLE EDM, and 4 (5.0 %) p53abn. Overall CR rates were comparable across four molecular subtypes, with 92.2 % of p53wt, 71.4 % of MMR-D, 100.0 % of POLE EDM, and 75.0 % of p53abn (P = 0.145). MMR-D patients needed the longest median treatment time to achieve CR (7.9 months, range 3.5-15.9), while POLE EDM required the shortest (3.0 months, range 2.8-6.4), followed by p53abn (3.5 months, range 3.0-3.7) and p53wt (3.7 months, range 2.2-22.8) (P = 0.049). Among 14 p53wt patients with superficial myometrial invasion (MI) or G2 histology, 13 (92.9 %) achieved CR, and of 8 who attempted to conceive,4 delivered. Multivariable analysis identified MMR-D, superficial MI and insulin resistance negatively predicted CR, while POLE EDM was a positive factor. CONCLUSIONS: Molecular classification of EC may serve as a tool for predicting response to FST and assist in identifying candidates for FST. POLE EDM patients tended to obtain promising outcomes. MMR-D cases should be cautiously administrated for FST with close surveillance. Patients with p53wt demonstrated favorable outcomes, including those with superficial MI or G2 EC. Patients with endometrium-confined p53abn tumors may benefit from FST. However, given the small sample sizes of certain subtypes, further investigation is necessary to validate these findings.
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Pullorum disease, an intestinal disease in chickens caused by Salmonella enterica serovar pullorum (S. Pullorum), is a significant threat to the poultry industry and results in substantial economic losses. The bacteria's transmission, both vertical and horizontal, makes it difficult to completely eliminate it. Control strategies for pullorum disease primarily involve stringent eradication programs that cull infected birds and employ antibiotics for treatment. However, eradication programs are costly, and antibiotic use is restricted. Therefore, developing alternative control strategies is essential. Increasingly, studies are focusing on modulating the gut microbiota to control intestinal diseases. Modulating the chicken gut microbiota may offer a novel strategy for preventing and controlling pullorum disease in poultry. However, the impact of S. Pullorum on the chicken gut microbiota has not been well established, prompting our exploration of the relationship between S. Pullorum and the chicken gut microbiota in this study. In this study, we initially analyzed the dynamic distribution of the gut microbiota in chickens infected with S. Pullorum. Alpha diversity analysis revealed a decrease in observed OTUs and the Shannon diversity index in the infected group, suggesting a reduction in the richness of the chicken gut microbiota due to S. Pullorum infection. Principal coordinate analysis (PCoA) showed distinct clusters between the gut microbiota of infected and uninfected groups, indicating S. Pullorum infection changed the chicken gut microbiota structure. Specifically, S. Pullorum infection enriched the relative abundance of the genera Escherichia-Shigella (65% in infected vs. 40.6% in uninfected groups) and Enterococcus (10.8% vs. 3.7%) while reducing the abundance of Lactobacillus (9.9% vs. 32%) in the chicken microbiota. Additionally, based on the observed changes in the chicken gut microbiota, we isolated microorganisms, including Bifidobacterium pseudolongum, Streptococcus equi and Lacticaseibacillus paracasei (L. paracasei), which were decreased by S. Pullorum infection. Notably, the L. paracasei Lp02 strain was found to effectively inhibit S. Pullorum proliferation in vitro and alleviate its infection in vivo. We found that S. Pullorum infection reduced the richness of the chicken gut microbiota and enriched the relative abundance of the genera Escherichia-Shigella and Enterococcus while decreasing the abundance of the anaerobic genus Lactobacillus. Furthermore, microbiota analysis enabled the isolation of several antimicrobial microorganisms from healthy chicken feces, with a L. paracasei strain notably inhibiting S. Pullorum proliferation in vitro and alleviating its infection in vivo. Overall, this research enhances our understanding of the interaction between gut microbiota and pathogen infection, as well as offers new perspectives and strategies for modulating the chicken gut microbiota to control pullorum disease.
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Oxidative desulfurization (ODS), as a novel desulfurization technique of fuel oil, possesses high desulfurization efficiency for aromatic sulfide and low cost, making it a promising approach. The key to the technology lies in the rational design of catalysts with high activity and stability. Polyoxometalates, which are environmentally friendly, cost-effective, and abundantly available, face constraints in the development of ODS applications due to their low specific surface area and difficulty in regeneration. Introducing metal oxides into carriers with large specific surface areas to obtain heterogeneous catalysts is an effective solution to this problem. Beta zeolites, with regular three-dimensional channel systems, large specific surface area, and superior thermal/hydrothermal stability, are usually used as carriers. In this work, we developed a strategy to enhance zeolite carrier utilization efficiency by introducing Ta5+ species into the rigid framework of zeolites containing confined MoO3. The Ta species in the zeolite framework and the confined MoO3 produce a synergistic effect, exhibiting extremely high catalytic activity for the aerobic oxidative desulfurization of various organic aromatic sulfur compounds under mild conditions (90 °C and atmospheric pressure) in a deep eutectic solvent, surpassing common heterogeneous catalysts for oxidative desulfurization. Moreover, it can resist the adverse effects of interferents, such as naphthalene and indole. Additionally, the confined nature of Beta zeolite endows it with exceptional stability, demonstrating distinctive recyclability.
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In the avian species, genetic modification by cell nuclear transfer is infeasible due to its unique reproductive system. The in vitro primordial germ cell modification approach is difficult and cumbersome, although it is the main method of genetic modification in chickens. In the present study, the adenoviral CRISPR/Cas9 vector was directly microinjected into the dorsal aorta of chicken embryos to achieve in vivo genetic modification. The results demonstrated that keratin 75-like 4 (KRT75L4), a candidate gene crucial for feather development, was widely knocked out, and an 8bp deletion was the predominant mutation that occurred in multiple tissues in chimeras, particularly in the gonad (2.63-11.57%). As we expected, significant modification was detected in the sperm of G0 (0.16-4.85%), confirming the potential to generate homozygous chickens and establishing this vector as a simple and effective method for genetic modification in avian species.
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Adenoviridae , Aorta , Sistemas CRISPR-Cas , Galinhas , Vetores Genéticos , Animais , Embrião de Galinha , Vetores Genéticos/genética , Galinhas/genética , Adenoviridae/genética , Aorta/metabolismo , Edição de Genes/métodos , MasculinoRESUMO
OBJECTIVES: To examine the associated risk of cervical intraepithelial neoplasm grade 3+ (CIN3+) lesions in patients with AGC and extensive human papillomavirus (HPV) genotyping. METHODS: Cases with atypical glandular cell (AGC) interpretation on a Papanicolaou (Pap) test were identified along with associated extensive HPV genotyping and histologic follow-up results. RESULTS: Within this cohort of 469,694 Pap tests, 0.4% were diagnosed as AGCs. In total, 1267 cases had concurrent high-risk HPV (hrHPV) genotyping, and 40.3% were hrHPV positive. The percentage of AGC cases with cervical CIN3+ on histologic follow-up was 52.2% when hrHPV was positive, whereas it was 4.9% with a negative hrHPV result. The top 5 hrHPV genotypes associated with cervical CIN3+ in this cohort were HPV16, HPV18, HPV58, HPV52, and HPV33. Indeed, 92.8% of the hrHPV-associated CIN3+ lesions identified in this cohort were positive for at least one of these HPV genotypes. The sensitivity of detecting cervical CIN3+ lesions was 85.6% with the top 5 hrHPV genotypes (HPV16/18/58/52/33) and only increased to 89.0% when the additional 12 genotypes were included. CONCLUSIONS: In patients with an AGC Pap, the risk of having a cervical CIN3+ lesion is greatly increased by positivity for hrHPV types 16, 18, 58, 52, and/or 33. Incorporating comprehensive HPV genotyping into AGC cytology allows for refined risk stratification and more tailored management strategies.
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The Si/Al molar ratio of MAZ aluminosilicate zeolite prepared by the direct hydrothermal method is generally less than five, thus giving rise to poor thermal and hydrothermal stability for this low-silica zeolite. With the purpose of enhancing the Si/Al molar ratio of MAZ zeolite, post-synthesized methods including acetic acid treatment and steaming treatment, as well as interzeolite transformation from FAU zeolite, were employed to prepare MAZ zeolite with high silica. It was found that steaming treatment was more effective in increasing the Si/Al molar ratio in comparison with acetic acid treatment, affording a maximum Si/Al molar ratio of 16.9 along with a preserved crystallinity of approximately 75%. Additionally, high-silica MAZ zeolite with a Si/Al molar ratio of up to 7.3 was also capable of being directly hydrothermally synthesized using interzeolite transformation from FAU zeolite.
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A series of dual-band photomultiplication (PM)-type organic photodetectors (OPDs) were fabricated by employing a donor(s)/acceptor (100:1, wt/wt) mixed layer and an ultrathin Y6 layer as the active layers, as well as by using PNDIT-F3N as an interfacial layer near the indium tin oxide (ITO) electrode. The dual-band PM-type OPDs exhibit the response range of 330-650 nm under forward bias and the response range of 650-850 nm under reverse bias. The tunable spectral response range of dual-band PM-type OPDs under forward or reverse bias can be explained well from the trapped electron distribution near the electrodes. The dark current density (JD) of the dual-band PM-type OPDs can be efficiently suppressed by employing PNDIT-F3N as the anode interfacial layer and the special active layers with hole-only transport characteristics. The light current density (JL) of the dual-band PM-type OPDs can be slightly increased by incorporating wide-bandgap polymer P-TPDs with relatively large hole mobility (µh) in the active layers. The signal-to-noise ratios of the optimized dual-band PM-type OPDs reach 100,980 under -50 V bias and white light illumination with an intensity of 1.0 mW·cm-2, benefiting from the ultralow JD by employing wide-bandgap PNDIT-F3N as the anode interfacial buffer layer and the increased JL by incorporating appropriate P-TPD in the active layers.
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BACKGROUND: We aim to identify the distinct lesion patterns and regions associated with functional outcome and inflammation in patients with acute ischemic stroke, and investigate whether the association between lesion patterns and functional outcome was mediated by inflammation. METHODS AND RESULTS: We performed nonnegative matrix factorization to derived low-dimensional lesion patterns (atoms), and Bayesian linear regression models were applied to explore the associations of lesion patterns with inflammatory factors including high-sensitivity C-reactive protein and interleukin-6, as well as functional outcome (defined as modified Rankin Scale score at 3 months). The difference distribution mean and 95% highest probability density interval (HPDI) were calculated. Mediation analysis was used to examine the mediating effects of inflammation on the relationships between lesion patterns and functional outcome. Seven lesion patterns were derived from 5914 patients with acute ischemic stroke. Lesion patterns distributed in the cortical regions were associated with inflammatory response, including atom 1 (interleukin-6: mean, 0.113 [95% HPDI, 0.073-0.162]; high-sensitivity C-reactive protein: mean, 0.082 [95% HPDI, 0.038-0.123]) and atom 4 (interleukin-6: mean, 0.113 [95% HPDI, 0.071-0.167]; high-sensitivity C-reactive protein: mean, 0.108 [95% HPDI, 0.058-0.165]). These lesion patterns were also significantly associated with functional outcome (atom 1: mean, 1.958 [95% HPDI, 1.538-2.383]; atom 4: mean, 2.245 [95% HPDI, 1.773-2.741]). Mediation analysis suggested that interleukin-6 explained 15.34% and 7.47% in the association of atom 1 and atom 4 with functional outcome, respectively. CONCLUSIONS: Certain lesion patterns that are associated with both inflammation and functional outcome of acute ischemic stroke, especially cortical infarction, may play a role in functional outcome through modulating inflammatory reactions.
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Proteína C-Reativa , Inflamação , Interleucina-6 , AVC Isquêmico , Humanos , Masculino , Feminino , Estudos Retrospectivos , Idoso , Prognóstico , Proteína C-Reativa/análise , Proteína C-Reativa/metabolismo , Pessoa de Meia-Idade , Interleucina-6/sangue , Biomarcadores/sangue , Teorema de Bayes , Imageamento por Ressonância Magnética , Infarto Cerebral/patologiaRESUMO
Previous studies on temperature and infectious diseases primarily focused on individual disease types, yielding inconsistent conclusions. This study collected monthly data on notifiable infectious disease cases and meteorological variables across 7 provinces in China from 2011 to 2019. A distributed lag nonlinear model was used to evaluate the association between ambient temperature and infectious diseases within each province, and random meta-analysis was applied to evaluate the pooled effect. Extreme hot temperature (the 97.5th percentile) was positively associated with the risk of respiratory infectious diseases with the relative risk (RR) of 1.45 (95%CI: 1.01-2.08). Conversely, extreme cold temperature (the 2.5th percentile) was negatively associated with intestinal infectious diseases and zoonotic diseases and vector-borne diseases, reporting RRs of 0.43 (95%CI: 0.30-0.60) and 0.46 (95%CI: 0.38-0.57), respectively. This study described the nonlinear association between ambient temperature and infectious diseases with different transmission routes, informing comprehensive prevention and control strategies for temperature-related infectious diseases.
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Highly crystalline ZSM-23 zeolite, exhibiting a distinctive dumbbell morphology, was synthesized via a hydrothermal method. Bifunctional catalysts, comprising single metals (Pt or Au) and bimetals (Pt-Au), were successfully prepared by using a positional precipitation method. The hydroisomerization of hexadecane served as a model reaction to assess the catalytic performance arising from the synergistic effects of bimetallic active sites. In comparison to single-metal catalysts, 0.3Au0.7Pt/ZSM-23 demonstrated increased n-C16 conversion, while 0.5Au0.5Pt/ZSM-23 exhibited enhanced i-C16 selectivity, achieving the highest i-C16 yield. The bimetallic catalyst not only finely tuned the metal site activity through bimetallic synergy but also achieved a superior balance between metal and acid catalysis, resulting in improved catalytic performance in the n-C16 hydroisomerization. The Pt-Au bimetallic catalyst approached the ideal requirements for a hydroisomerization catalyst, achieving a harmonious balance of metal and acid catalysis.
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The rapid development of deep neural networks has attracted significant attention in the infrared and visible image fusion field. However, most existing fusion models have many parameters and consume high computational and spatial resources. This paper proposes a fast and efficient recursive fusion neural network model to solve this complex problem that few people have touched. Specifically, we designed an attention module combining a traditional fusion knowledge prior with channel attention to extract modal-specific features efficiently. We used a shared attention layer to perform the early fusion of modal-shared features. Adopting parallel dilated convolution layers further reduces the network's parameter count. Our network is trained recursively, featuring minimal model parameters, and requires only a few training batches to achieve excellent fusion results. This significantly reduces the consumption of time, space, and computational resources during model training. We compared our method with nine SOTA methods on three public datasets, demonstrating our method's efficient training feature and good fusion results.
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Lead poisoning is globally concerning, yet limited testing hinders effective interventions in most countries. We aimed to create annual maps of county-specific blood lead levels in China from 1980 to 2040 using a machine learning model. Blood lead data from China were sourced from 1180 surveys published between 1980 and 2022. Additionally, regional statistical figures for 15 natural and socioeconomic variables were obtained or estimated as predictors. A machine learning model, using the random forest algorithm and 2973 generated samples, was created to predict county-specific blood lead levels in China from 1980 to 2040. Geometric mean blood lead levels in children (i.e., age 14 and under) decreased significantly from 104.4 µg/L in 1993 to an anticipated 40.3 µg/L by 2040. The number exceeding 100 µg/L declined dramatically, yet South Central China remains a hotspot. Lead exposure is similar among different groups, but overall adults and adolescents (i.e., age over 14), females, and rural residents exhibit slightly lower exposure compared to that of children, males, and urban residents, respectively. Our predictions indicated that despite the general reduction, one-fourth of Chinese counties rebounded during 2015-2020. This slower decline might be due to emerging lead sources like smelting and coal combustion; however, the primary factor driving the decline should be the reduction of a persistent source, legacy gasoline-derived lead. Our approach innovatively maps lead exposure without comprehensive surveys.
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Chumbo , Aprendizado de Máquina , Chumbo/sangue , China , Humanos , Feminino , Masculino , Criança , Adolescente , Exposição Ambiental , Intoxicação por Chumbo/epidemiologia , Intoxicação por Chumbo/sangueRESUMO
INTRODUCTION: To compare the perfusion volumes assessed by a new automated CT perfusion (CTP) software iStroke with the circular singular value decomposition software RAPID and determine its predictive value for functional outcome in patients with acute ischaemic stroke (AIS) who underwent endovascular treatment (EVT). METHODS: Data on patients with AIS were collected from four hospitals in China. All patients received CTP followed by EVT with complete recanalisation within 24 hours of symptom onset. We evaluated the agreement of CTP measures between the two softwares by Spearman's rank correlation tests and kappa tests. Bland-Altman plots were used to evaluate the agreement of infarct core volume (ICV) on CTP and ground truth on diffusion-weighted imaging (DWI). Logistic regression models were used to test the association between ICV on these two softwares and functional outcomes. RESULTS: Among 326 patients, 228 had DWI examinations and 40 of them had infarct volume >70 mL. In all patients, the infarct core and hypoperfusion volumes on iStroke had a strong correlation with those on RAPID (ρ=0.68 and 0.66, respectively). The agreement of large infarct core (volume >70 mL) was substantial (kappa=0.73, p<0.001) between these two softwares. The ICV measured by iStroke and RAPID was significantly correlated with independent functional outcome at 90 days (p=0.009 and p<0.001, respectively). In patients with DWI examinations and those with an ICV >70 mL, the ICV of iStroke and RAPID was comparable on individual agreement with ground truth. CONCLUSION: The automatic CTP software iStroke is a reliable tool for assessing infarct core and mismatch volumes, making it clinically useful for selecting patients with AIS for acute reperfusion therapy in the extended time window.
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BACKGROUND: The structure and staffing of hospitals greatly impact patient outcomes, with frequent changes occurring during nights and weekends. This retrospective cohort study assessed the impact of admission timing on in-hospital management and outcomes for patients with stroke receiving reperfusion therapy in China using data from a nationwide registry. METHODS: Data from patients receiving reperfusion therapy were extracted from the Chinese Stroke Center Alliance. Hospital admission time was categorized according to day/evening versus night and weekday versus weekend. Primary outcomes were in-hospital death or discharge against medical advice, hemorrhage transformation, early neurological deterioration, and major adverse cardiovascular events. Logistic regression was performed to compare in-hospital management performance and outcomes based on admission time categories. RESULTS: Overall, 42â 381 patients received recombinant tissue-type plasminogen activator (r-tPA) therapy, and 5224 underwent endovascular treatment (EVT). Patients admitted during nighttime had a higher probability of receiving r-tPA therapy within 4.5 hours from onset or undergoing EVT within 6 hours from onset compared with those admitted during day/evening hours (adjusted odds ratio, 1.04 [95% CI, 1.01-1.08]; P=0.021; adjusted odds ratio, 1.72 [95% CI, 1.59-1.86]; P<0.001, respectively). However, no significant difference was observed between weekend and weekday admissions for either treatment. No notable differences were noted between weekends and weekdays or nighttime and daytime periods in door-to-needle time for r-tPA or door-to-puncture time for EVT initiation. Furthermore, weekend or nighttime admission did not have a significant effect on the primary outcomes of r-tPA therapy or EVT. Nevertheless, in patients undergoing EVT, a higher incidence of pneumonia was observed among those admitted at night compared with those admitted during day/evening hours (adjusted odds ratio, 1.22 [95% CI, 1.05-1.42]; P=0.011). CONCLUSIONS: Patients admitted at nighttime were more likely to receive r-tPA therapy or EVT within the time window recommended in the guidelines. However, patients receiving EVT admitted at night had an increased risk of pneumonia.
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The impact of drought on terrestrial ecosystems is increasing, and the spatiotemporal heterogeneity of drought changes exacerbates the difficulty of determining ecosystem responses, especially in arid regions far from oceans. Tree rings have been widely used to understand how forest ecosystems respond to drought. However, the link between local hydroclimate variations related to tree rings and large-scale climate changes is not clear in the Qilian Mountains. Here, we used the tree ring width index to analyze the trend of Picea crassifolia growth and its relationship with climate in the middle Qilian Mountains. The results showed that the radial growth trend of Picea crassifolia is synchronized in the middle Qilian Mountains by calculating the Gleichläufigkeit index (GLK). Our analyses indicated that tree radial growth is positively correlated with drought during the growing season. Tree growth responds stably to drought (scPDSI and SPEI) and precipitation but unstably to temperature during 1950-2019. We further traced the meteorological factors that cause regional drought changes associated with radial growth. An increased total precipitation and decreased evaporation contribute to drought alleviation, favoring an increased tree radial growth. The increased total precipitation is mainly due to increased large-scale precipitation, which is related to water vapor transport changes. This study attempts to explore the influence of large-scale meteorology on regional drought change and its related tree radial growth response, which helps us to better understand the changes in forest ecosystems under climate change.
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Mudança Climática , Secas , Árvores , Árvores/crescimento & desenvolvimento , Chuva , Picea/crescimento & desenvolvimento , China , Clima Desértico , FlorestasRESUMO
BACKGROUND AND OBJECTIVES: Prior evidence suggests that atrial fibrillation detected after stroke (AFDAS) is distinct from known atrial fibrillation (KAF), with particular clinical characteristics and impacts on outcomes in ischaemic stroke. However, the results remained inconsistent in ischaemic stroke, and the role of AFDAS in haemorrhagic stroke remains unclear. Therefore, we aimed to estimate the prevalence, risk factors and prognostic value of AFDAS in haemorrhagic stroke in comparison with ischaemic stroke. METHODS: This was a multicentre cohort study. Patients who had an ischaemic and haemorrhagic stroke hospitalised in the Chinese Stroke Center Alliance hospitals were enrolled and classified as AFDAS, KAF or sinus rhythm (SR) based on heart rhythm. Univariate and multivariate logistic regression analyses were used to assess the prevalence, characteristics, risk factors and outcomes of AFDAS, KAF and SR in different stroke subtypes. RESULTS: A total of 913 163 patients, including 818 799 with ischaemic stroke, 83 450 with intracerebral haemorrhage (ICH) and 10 914 with subarachnoid haemorrhage (SAH), were enrolled. AFDAS was the most common in ischaemic stroke. There were differences in the risk factor profile between stroke subtypes; older age is a common independent risk factor shared by ischaemic stroke (OR 1.06, 95% CI 1.06 to 1.06), ICH (OR 1.08, 95% CI 1.07 to 1.09) and SAH (OR 1.07, 95% CI 1.05 to 1.10). Similar to KAF, AFDAS was associated with an increased risk of in-hospital mortality compared with SR in both ischaemic stroke (OR 2.23, 95% CI 1.94 to 2.56) and ICH (OR 2.84, 95% CI 1.84 to 4.38). DISCUSSION: There are differences in the prevalence, characteristics and risk factors for AFDAS and KAF in different stroke subtypes. AFDAS was associated with an increased risk of mortality compared with SR in both ischaemic stroke and ICH. Rhythm monitoring and risk factor modification after both ischaemic and haemorrhagic stroke are essential in clinical practice. More emphasis and appropriate treatment should be given to AFDAS.
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This study explored the impact of non-thermal plasma and CO2 on the flame soot characteristics within the diffusion flames. We analyzed on flame structures that were diluted with either CO2 or N2, temperature distributions, and soot characteristics, both in the presence and absence of plasma. Due to the higher specific heat capacity of CO2 compared to N2, the optical observations consistently showed lower temperatures in flames diluted with CO2 as compared to those diluted with N2. The inclusion of plasma and carbon dioxide resulted in the lowest soot concentration, indicating that plasma coupled with CO2 has a synergistic inhibitory effect on soot emissions. The findings revealed that when CO2 was used to dilute the flames and the oxygen concentration was low, the soot nanostructure appeared amorphous. Raman results showed that the level of graphitization observed in soot particles from CO2 dilution flames was lower than that from N2 dilution flames. In the presence of plasma and CO2, the soot obtained exhibited the shortest fringe length and the highest fringe tortuosity. Significant correlations were observed between the nanostructure of soot and its reactivity. The combined application of plasma and CO2 proved to be effective in reducing the soot carbonization degree.