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1.
J Environ Manage ; 354: 120308, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38377751

RESUMO

Urban flood risk assessment plays a crucial role in disaster prevention and mitigation. A scientifically accurate assessment and risk stratification method are of paramount importance for effective flood risk management. This study aims to propose a comprehensive urban flood risk assessment approach by coupling GeoDetector-Dematel and Clustering Method to enhance the accuracy of urban flood risk evaluation. Based on simulation results from hydraulic models and existing literature, the research established a set of urban flood risk assessment indicators comprising 10 metrics across two dimensions: hazard factors and vulnerability factors, among which vulnerability factors include exposure factors, sensitivity factors, and adaptability factors. Subsequently, the research introduced the GeoDetector-Dematel method to determine indicator weights, significantly enhancing the scientific rigor and precision of weight calculation. Finally, the research employed the K-means clustering method to risk zonation, providing a more scientifically rational depiction of the spatial distribution of urban flood risks. This novel comprehensive urban flood risk assessment method was applied in the Fangzhuang area of Beijing. The results demonstrated that this integrated approach effectively enhances the accuracy of urban flood risk assessment. In conclusion, this research offers a new methodology for urban flood risk assessment and contributes to decision-making in disaster prevention and control measures.


Assuntos
Desastres , Inundações , Desastres/prevenção & controle , Medição de Risco/métodos , Pequim , Fatores de Risco
2.
Plant Dis ; 2022 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-35488363

RESUMO

Mesona chinensis is an important medicinal and edible plant resource distributed in eight provinces in southern China. In December 2021, an unknown stem and leaf blight disease was found in M. chinensis cultivation areas in Longzhou County, Guangxi, China. Sixty days after transplanting, the incidence of this disease was 10%. Leaf spots mostly appeared from the leaf edge, were irregular, brown to dark brown, causing more than half of the leaf or the whole leaf to die. The infected stem first showed dark brown spots, then constricted slightly, became necrotic and rotted with the expansion of the spots, resulting in the death of the whole plant. Loose cobweb-like mycelia, which resembled Rhizoctonia, could be seen on the diseased tissues in conditions of high humidity. To identify the pathogen, diseased stems and leaves with typical symptoms from Longzhou County were collected and surface-sterilized with 75% ethanol for 30 s. Small fragments (5×5 mm) at the junction of diseased and healthy tissues were disinfected with 1% NaClO for 1min, washed with sterile water three times, transferred to potato dextrose agar (PDA), and incubated at 28°C for 3 days. Mycelial tips were removed, and six isolates (No. R1-R6) were obtained. The colonies were initially gray white and later light brown. Many nearly round to irregular sclerotia appeared after 7 days of culture. The sclerotia turned from light brown to deep brown and were 1 to 5 mm in diameter. The mycelium branched at a 90° angle, with septa near the branches and a constriction of the mycelium at the base of the branch. These morphological characteristics were consistent with Rhizoctonia. For molecular identification, genomic DNA of the six isolates was obtained using an extraction kit (Biocolor, Shanghai, China), and primers ITS4/ITS5 were used to amplify the internal transcribed spacers (ITS) and 5.8S rRNA (White et al. 1990). A 750 bp DNA fragment was obtained and the sequences were deposited in GenBank (OM095383-OM095388). All isolates had ≥ 99% identity with anastomosis group AG1-1B (HG934429 and HQ185364) of R. solani. A phylogenetic tree showed that the isolates and those from anastomosis group AG1-1B clustered into one branch. To satisfy Koch's postulates, the isolates from diseased leaf (No. R1, R2, and R3) and diseased stem (No. R4, R5, and R6) were inoculated on leaves and stems of 45-day-old M. chinensis plants. Five leaves and stems were inoculated with mycelial plugs of each isolate without wounding and another five leaves and stems were inoculated with mycelial plugs of each isolate after pinprick wounding. Control wounded leaves and stems were inoculated with sterile PDA discs. To maintain high humidity, the plants were incubated at 28°C and covered with transparent plastic covers. Diseased spots first appeared 24 h after inoculation. Three days post-inoculation, all inoculated leaves and stems showed symptoms like those observed in the field, whereas controls were asymptomatic. The pathogen was re-isolated from the diseased inoculated tissues using the method described above, and isolated fungi had the morphological characteristics of R. solani. Thus, the pathogen causing stem and leaf blight disease of M. chinensis was determined to be R. solani. The host range of R. solani is wide, and anastomosis group AG1-1B has been reported to infect plants such as rice, bean, fig, cabbage, and lettuce (Sneh et al. 1991). To our knowledge, this is the first report of R. solani causing a stem and leaf blight on M. chinensis, and provides a basis for diagnosis and control of the disease.

3.
Ann Plast Surg ; 86(4): 440-443, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-32842031

RESUMO

BACKGROUND: Reconstruction of digital loss with soft tissue defects remains a tough challenge. Although a combined flap of toe and dorsal foot skin provides a good option for "like-for-like" hand reconstruction, the disappointed donor site morbidity prevents it from popularity. In this study, we presented experiences of the superficial peroneal neurocutaneous (SPNC) flap for donor site closure after the combined toe and dorsal foot flap transfer. METHODS: Superficial peroneal neurocutaneous flaps were used to cover foot donor site defects in 9 patients. The flaps harvested from feet including 3 cases of wrap-around flap with dorsal foot flap, 4 cases of 2nd toe flap with dorsal foot flap, 2 cases of 2nd and 3rd toe flap with dorsal foot flap. The flap size, operation time, and complications were documented, and the donor sites were evaluated by the subjective outcome measure, the foot evaluation questionnaire, and the Vancouver Scar Scale. RESULTS: All flaps but one survived completely without complications. Marginal necrosis occurred in the distal part of the flap in one case, which was treated by daily dressings. The skin grafts on the lower leg healed uneventfully. The average operation time of flap transfer was 40 minutes. Follow-up ranged from 9 to 16 months, and patients were content with the results of the foot donor site according to the outcome measures. All the patients were able to wear normal shoes walking and running with a normal gait, and none sustained complications of skin erosion or ulceration. Protective sensibility was obtained in all the flaps. Two patients complained of cold intolerance and 2 could not wear a thong sandal. The donor site scars on the lower leg were measured 3.2 on average on the Vancouver Scar Scale. CONCLUSIONS: The SPNC flap is a practical procedure for donor site closure on the foot, especially when extra dorsal foot skin is elevated with a toe flap for hand reconstruction.


Assuntos
Procedimentos de Cirurgia Plástica , Lesões dos Tecidos Moles , Humanos , Transplante de Pele , Lesões dos Tecidos Moles/cirurgia , Retalhos Cirúrgicos , Dedos do Pé/cirurgia , Resultado do Tratamento
4.
Nanomedicine ; 21: 102078, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31400573

RESUMO

Heterotopic ossification (HO) is a painful disease characterized by unwanted bone ectopic formation outside of the skeleton after injury. SPIO nanoparticles therapy has been widely used in diverse orthopedic diseases. However, the effect of SPIO nanoparticles on heterotopic ossification remains unknown. Here, we prepared the SPIO nanoparticles carrying mothers against decapentaplegic homolog 7 (SMAD7) and evaluated their mechanism function to HO in a rat model. The results revealed that SPIO nanoparticles containing SMAD7 treatment lead to a decrease in epithelial-mesenchymal transition (EMT) relevant protein expression in vitro. Moreover, SPIO nanoparticles labeled EPCs transplantation effectively prevented heterotopic ossification and inhibited endothelial-mesenchymal transition (EndMT) in HO rats. In addition, SPIO nanoparticles labeled EPCs transplantation suppressed osteogenic and adipogenic differentiation of embryonic fibroblasts (EFs) in HO rats. Our results demonstrated that administration of SPIO nanoparticles labeled EPCs could inhibit heterotopic ossification in rats, which might be a potential therapy method for a medical intervention to treat HO in clinic.


Assuntos
Células Progenitoras Endoteliais , Nanopartículas de Magnetita/química , Ossificação Heterotópica , Transplante de Células-Tronco , Aloenxertos , Animais , Células Progenitoras Endoteliais/metabolismo , Células Progenitoras Endoteliais/patologia , Células Progenitoras Endoteliais/transplante , Transição Epitelial-Mesenquimal , Células HEK293 , Humanos , Masculino , Ossificação Heterotópica/metabolismo , Ossificação Heterotópica/patologia , Ossificação Heterotópica/terapia , Ratos , Ratos Sprague-Dawley , Proteína Smad7/antagonistas & inibidores
5.
J Environ Manage ; 213: 440-450, 2018 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-29505999

RESUMO

Flood is a serious challenge that increasingly affects the residents as well as policymakers. Flood vulnerability assessment is becoming gradually relevant in the world. The purpose of this study is to develop an approach to reveal the relationship between exposure, sensitivity and adaptive capacity for better flood vulnerability assessment, based on the fuzzy comprehensive evaluation method (FCEM) and coordinated development degree model (CDDM). The approach is organized into three parts: establishment of index system, assessment of exposure, sensitivity and adaptive capacity, and multiple flood vulnerability assessment. Hydrodynamic model and statistical data are employed for the establishment of index system; FCEM is used to evaluate exposure, sensitivity and adaptive capacity; and CDDM is applied to express the relationship of the three components of vulnerability. Six multiple flood vulnerability types and four levels are proposed to assess flood vulnerability from multiple perspectives. Then the approach is applied to assess the spatiality of flood vulnerability in Hainan's eastern area, China. Based on the results of multiple flood vulnerability, a decision-making process for rational allocation of limited resources is proposed and applied to the study area. The study shows that multiple flood vulnerability assessment can evaluate vulnerability more completely, and help decision makers learn more information about making decisions in a more comprehensive way. In summary, this study provides a new way for flood vulnerability assessment and disaster prevention decision.


Assuntos
Desastres , Inundações , Lógica Fuzzy , China , Modelos Teóricos
6.
Environ Toxicol ; 31(12): 1869-1878, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26303504

RESUMO

Inhaled PM2.5 (particulate matter with an aerodynamic diameter of 2.5 µm or less) can induce lung inflammation through released inflammatory mediators from airway cells, such as interleukin-8 (IL-8) and tumor necrosis factor alpha (TNF-α). However, the mechanisms underlying PM2.5-induced IL-8 gene expression have not been fully characterized. BEAS-2B cells (a human bronchial epithelial cell line) and THP-1 cells (a human macrophage-like cell line) were used as the in vitro models to investigate the underlying mechanism in this study. IL-8 expression was increased in the cells treated with PM2.5 in a dose-dependent manner. The water-soluble and insoluble fractions of PM2.5 suspension were both shown to induce IL-8 expression. PM2.5 exposure could obviously induce ROS (reactive oxygen species) generation, indicative of oxidative stress. Pretreatment with the antioxidant N-acetyl-l-cysteine (NAC) potently inhibited PM2.5-induced IL-8 expression. Employment of the transition metal chelators including TPEN (N,N,N',N'-tetrakis (2-pyridylmethyl) ethylenediamine) or DFO (desferrioxamine) inhibited IL-8 expression induced by PM2.5 by over 20% in BEAS-2B cells, but had minimal effect in THP-1 cells. Pretreatment with the endocytosis inhibitor CytD markedly blocked IL-8 expression induced by PM2.5 in both BEAS-2B and THP-1 cells. In summary, exposure to PM2.5 induced IL-8 gene expression through oxidative stress induction and endocytosis in airway cells. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 1869-1878, 2016.


Assuntos
Poluentes Atmosféricos/toxicidade , Brônquios/efeitos dos fármacos , Endocitose , Interleucina-8/metabolismo , Estresse Oxidativo , Material Particulado/toxicidade , Mucosa Respiratória/efeitos dos fármacos , Acetilcisteína/farmacologia , Antioxidantes/farmacologia , Brônquios/citologia , Brônquios/metabolismo , Linhagem Celular , Células Epiteliais/efeitos dos fármacos , Humanos , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Mucosa Respiratória/citologia , Mucosa Respiratória/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Regulação para Cima
7.
J Ind Microbiol Biotechnol ; 42(6): 897-904, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25860124

RESUMO

The co-culture system of the fermentation process of vitamin C can be regarded as an artificial microbial ecosystem (AME). To extend our understanding of this AME, an investigation of the relationship between strains, substrate and product was carried out in this study. The results showed that both Ketogulonicigenium vulgare and 2-keto-L-gulonic acid (2-KLG, the precursor of vitamin C) can inhibit the growth of the helper strain, while the helper strain promoted the growth of K. vulgare and 2-KLG production. Moreover, L-sorbose is not only a substrate for 2-KLG production in the AME, but also a promoter of K. vulgare and an inhibitor of the helper strain. In the earlier stage of fermentation, the inhibition of L-sorbose on the helper strain's growth is a key factor for ensuring an efficient fermentation. In the condition of adding the extra helper strain (OD: 0.57, ratio of inoculation: 2%), the yields of 2-KLG is increased by 9% in the 14% L-sorbose medium. To the best of our knowledge, this is the first report about the inhibition of substrate in the AME of 2-KLG production.


Assuntos
Reatores Biológicos , Fermentação , Sorbose/metabolismo , Açúcares Ácidos/metabolismo , Técnicas de Cocultura , Ecossistema , Fermentação/efeitos dos fármacos , Rhodobacteraceae/efeitos dos fármacos , Rhodobacteraceae/crescimento & desenvolvimento , Rhodobacteraceae/metabolismo , Sorbose/farmacologia
8.
Artigo em Zh | MEDLINE | ID: mdl-25876966

RESUMO

OBJECTIVE: To explore the protein expression of heme oxygenase-1 (HO-1) and platelet endothelial cell adhesion molecules-1 (PECAM-1) in human coronary artery endothelial cells induced with Zinc Oxide Nanoparticle (ZnO-NPs). METHODS: MTT assay was used to determine the cell viability of ZnO-NPs. Levels of HO-1 and PECAM-1 protein in culture supernatants were measured using ELISA after human coronary artery endothelial cells were treated with different concentrations (0, 10, 20, 40µg/ml) of ZnO-NPs for 24 h. RESULTS: The cell viability of human coronary artery endothelial cells in each group was 89.76%, 83.61%, 63.10%, 53.20%, 48.11%, 42.35%, 38.06%, 25.44% respectively when treated with different concentrations of ZnO-NPs (12.5, 25, 50, 70, 80, 90, 100, 200µg/ml). Protein levels of HO-1 (ng/L) in each group were 0.041±0.011, 0.512±0.076, 0.906±0.059, 1.062±0.089 respectively after the stimulation of different concentrations of ZnO-NPs (0, 10, 20, 40µg/ml). Comparisons in each group were statistically significant (P < 0.05). Protein levels of PECAM-1 (µg/L) in each group were 7.966 ± 0.046, 7.993 ± 0.036, 8.629 ± 0.052, 8.811 ± 0.039 respectively after the stimulation of different concentrations of ZnO-NPs (0, 10, 20, 40 µg/ml). Compared with the control group, protein levels of PECAM-1 increased (P < 0.05) when the concentration of ZnO-NPs was 20µg/ml or 40 µg/ml. CONCLUSION: ZnO-NPs stimulation could inhibit the viability of human coronary artery endothelial cells and upregulate the protein expression of HO-1 and PECAM-1.


Assuntos
Vasos Coronários , Células Endoteliais/efeitos dos fármacos , Heme Oxigenase-1/metabolismo , Nanopartículas/toxicidade , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , Óxido de Zinco/toxicidade , Plaquetas , Sobrevivência Celular , Humanos
9.
Biotechnol Lett ; 35(11): 1853-7, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23881329

RESUMO

A novel two-helper-strain co-culture system (TSCS) was developed to enhance 2-keto-L-gulonic acid (2-KLG) productivity for vitamin C production. Bacillus megaterium and B. cereus (with a seeding culture ratio of 1:3, v/v), used as helper strains, increased the 2-KLG yield using Ketogulonigenium vulgare compared to the conventional one-helper-strain (either B. cereus or B. megaterium) co-culture system (OSCS). After 45 h cultivation, 2-KLG concentration in the TSCS (69 g l(-1)) increased by 8.9 and 7 % over that of the OSCS (B. cereus: 63.4 g l(-1); B. megaterium: 64.5 g l(-1)). The fermentation period of TSCS was 4 h shorter than that of OSCS (B. cereus). The increased cell numbers of K. vulgare stimulated by the two helper strains possibly explain the enhanced 2-KLG yield. The results imply that TSCS is a viable method for enhancing industrial production of 2-KLG.


Assuntos
Bacillus cereus/crescimento & desenvolvimento , Bacillus megaterium/crescimento & desenvolvimento , Rhodobacteraceae/crescimento & desenvolvimento , Rhodobacteraceae/metabolismo , Açúcares Ácidos/metabolismo , Fermentação , Fatores de Tempo
10.
Wei Sheng Yan Jiu ; 42(4): 550-3, 570, 2013 Jul.
Artigo em Zh | MEDLINE | ID: mdl-24024362

RESUMO

OBJECTIVE: To examine the effect of exogenous zinc on enzymatic activity of tumor suppressor PTEN and underlying mechanisms. METHODS: Human airway epithelial cells (BEAS-2B) were employed as the in vitro model. Enzymatic activity of PTEN was measured using malachite green colorimetric assay and immunoblotting. Moreover, the activity of casein kinase-2 (CK-2), the upstream kinase of PTEN, was determined. RESULTS: Exposure of BEAS-2B cells to Zn2+ inhibited phosphatase activity of PTEN, as well as PTEN phosphorylation, indicative of PTEN activity (P < 0.05). Under the same experimental condition, Zn2+ stimulation resulted in significant reduction of CK-2 activity (P < 0.05). In addition, CK-2 was shown to induce PTEN phosphorylation (P < 0.05). CONCLUSION: These results suggested that Zn2+ exposure might inhibit PTEN phosphatase activity through inhibition of CK-2 activity in human airway epithelial cells.


Assuntos
Brônquios/citologia , Células Epiteliais/citologia , Células Epiteliais/enzimologia , PTEN Fosfo-Hidrolase/metabolismo , Zinco/farmacologia , Caseína Quinase II/metabolismo , Linhagem Celular , Humanos
11.
Polymers (Basel) ; 15(10)2023 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-37242971

RESUMO

With the continuous increase in sewage-sludge production worldwide, the pyrolytic disposal of sludge has received great attention. To build knowledge on the kinetics of pyrolysis, first, sludge was regulated using appropriate amounts of cationic polyacrylamide (CPAM) and sawdust to study their enhancing effect on dehydration. Due to the effects of the charge neutralization and skeleton hydrophobicity, a certain dose of CPAM and sawdust reduced the sludge's moisture content from 80.3% to 65.7%. Next, the pyrolysis characteristics of the dehydrated sludge regulated by CPAM and sawdust were investigated at a heating rate of 10~40 °C/min by using TGA method. The addition of sawdust enhanced the release of volatile substances and reduced the apparent activation energy of the sample. The maximum weight-loss rate decreased with the heating rate, and the DTG curves moved in the direction of high temperature. A model-free method, namely the Starink method, was adopted to calculate the apparent activation energies, which ranged from 135.3 kJ/mol to 174.8 kJ/mol. Combined with the master-plots method, the most appropriate mechanism function ultimately obtained was the nucleation-and-growth model.

12.
PeerJ Comput Sci ; 9: e1624, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38077572

RESUMO

The location of Low-Altitude Flight Service Station (LAFSS) is a comprehensive decision work, and it is also a multi-objective optimization problem (MOOP) with constraints. As a swarm intelligence search algorithm for solving constrained MOOP, the Immune Algorithm (IA) retains the excellent characteristics of genetic algorithm. Using some characteristic information or knowledge of the problem selectively and purposefully, the degradation phenomenon in the optimization process can be suppressed and the global optimum can be achieved. However, due to the large range involved in the low-altitude transition flight, the geographical characteristics, economic level and service requirements among the candidate stations in the corridor are quite different, and the operational safety and service efficiency are interrelated and conflict with each other. And all objectives cannot be optimal. Therefore, this article proposes a Modified Immune Algorithm (MIA) with two-layer response to solve the constrained multi-objective location mathematical model of LAFSS. The first layer uses the demand track as the cell membrane positioning pattern recognition service response distance to trigger the innate immunity to achieve the basic requirements of security service coverage. In the second layer, the expansion and upgrading of adjacent candidate sites are compared to the pathogen's effector, and the adaptive immunity is directly or indirectly triggered again through the cloning, mutation and reproduction between candidate sites to realize the multi-objective equilibrium of the scheme. Taking 486,000 km2 of Sichuan Province as an example, MIA for LAFSS is simulated by the MATLAB platform. Based on the Spring open source application framework of Java platform, the cesiumjs map data is called through easyui, and the visualization of site selection scheme is presented with the terrain data of Map World as the background. The experimental results show that, compared with dynamic programming and ordinary immunization, the immune trigger mode of double response and the improved algorithm of operation parameter combination designed by the Taguchi experiment, the total economic cost of location selection is reduced by 26.4%, the service response time is reduced by 25%, the repeat coverage rate is reduced by 29.5% and the effective service area is increased by 17.5%. The security risk, service efficiency and location cost are balanced. The present work is to provide an effective location method for the layout number and location of local transfer flight service stations. For complex scenes with larger scale of low-altitude flight supply and demand and larger terrain changes in the region, the above research methods can be used to effectively split and reduce the dimension.

13.
Animals (Basel) ; 13(15)2023 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-37570309

RESUMO

L-ascorbic acid (ASA) is a micronutrient that is essential for reproduction, growth, and immunity in animals. Due to the loss of enzyme L-gulono-1,4-lactone oxidase (GLO), most aquatic animals lack the capacity for ASA biosynthesis and therefore require supplementation with exogenous ASA. Recent studies have shown that 2-keto-L-gulonic acid (2KGA), a novel potential precursor of ASA, can enhance plant growth and improve stress resistance by promoting the synthesis and accumulation of ASA. Our hypothesis is that 2-keto-L-gulonic acid (2KGA) plays a similar role in aquatic animals. To investigate this, we conducted an in vivo trial to examine the effects of exogenous 2KGA supplementation on ASA metabolism and growth of zebrafish (Danio rerio). Zebrafish were categorized into groups based on their dietary intake, including a basal diet (CK group), a basal diet supplemented with 800 mg/kg ASA (ASA group), and 800 mg/kg 2KGA-Na (2KGA group) for a duration of three weeks. The results demonstrated a significant increase in ASA content in zebrafish treated with 2KGA (34.82% increase, p < 0.05) compared to the CK group, reaching a consistent level with the ASA group (39.61% increase, p < 0.05). Furthermore, the supplementation of 2KGA significantly improved growth parameters relevant to zebrafish (specific growth rate increased by 129.04%, p < 0.05) and enhanced feed utilization (feed intake increased by 15.65%, p < 0.05). Positive correlations were observed between growth parameters, feed utilization, whole-body chemical composition, and ASA content. Our findings suggest that supplementation with exogenous 2KGA can serve as a novel approach for elevating ASA synthesis in aquatic animals, and further investigation of its underlying mechanism is required.

14.
Sci Rep ; 13(1): 21459, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-38052914

RESUMO

The signal in the receiver is mainly a combination of different modulation types due to the complex electromagnetic environment, which makes the modulation recognition of the mixed signal a hot topic in recent years. In response to the poor adaptability of existing mixed signals recognition methods, this paper proposes a new recognition method for mixed signals based on cyclic spectrum projection and deep neural network. Firstly, through theoretical derivation, we prove the feasibility of using cyclic spectrum for mixed communication signal identification. Then, we adopt grayscale projections on the two-dimensional cyclic spectrum as identifying representation. And a new nonlinear piecewise mapping and directed pseudo-clustering method are used to enhance the above-mentioned grayscale images, which reduces the impact of energy ratios and symbol rates on signal identification. Finally, we use deep neural networks to extract deep abstract modulation information to achieve effective recognition of mixed signals. Simulation results show that the proposed method is robust against noise. When signal-to-noise ratio is not less than 0 dB, the average recognition rate is greater than 95%. Furthermore, this method exhibits good robustness towards the changes in signal symbol rates and energy ratios between mixed signals.

15.
Front Neurol ; 14: 1148878, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37251219

RESUMO

Purpose: This study aims to investigate the glymphatic system activity changes in patients with mild traumatic brain injury (mTBI), particularly in MRI-negative patients, using analysis along the perivascular space (ALPS) technology. Methods: A total of 161 mTBI patients (age: 15-92 years old) and 28 healthy controls (age: 15-84 years old) were included in this retrospective study. The mTBI patients were divided into MRI-negative and MRI-positive groups. ALPS index was calculated automatically using whole-brain T1-MPRAGE imaging and diffusion tensor imaging. The Student's t and chi-squared tests were performed to compare the ALPS index, age, gender, course of disease, and Glasgow Coma Scale (GCS) score between groups. Correlations among ALPS index, age, course of disease and GCS score were computed using Spearman's correlation analysis. Results: Increased activity of the glymphatic system was suggested in mTBI patients based on ALPS index analysis, including the MRI-negative patients. There was a significant negative correlation between the ALPS index and age. In addition, a weak positive correlation between the ALPS index and course of disease was also observed. On the contrary, there was no significant correlation between the ALPS index and sex nor between the ALPS index and GCS score. Conclusion: Our study demonstrated that the activity level of the glymphatic system was enhanced in mTBI patients, even when their brain MRI scans were negative. These findings may provide novel insights for understanding the pathophysiology of mild TBI.

16.
Front Cell Dev Biol ; 11: 1276098, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38161331

RESUMO

Background: Single-cell RNA sequencing (scRNA-seq) enables specific analysis of cell populations at single-cell resolution; however, there is still a lack of single-cell-level studies to characterize the dynamic and complex interactions between osteoporotic vertebral compression fractures (OVCFs) and Kümmell's disease (KD) in the osteoimmune microenvironment. In this study, we used scRNA-seq analysis to investigate the osteoimmune microenvironment and cellular composition in OVCFs and KD. Methods: ScRNA-seq was used to perform analysis of fractured vertebral bone tissues from one OVCF and one KD patients, and a total of 8,741 single cells were captured for single-cell transcriptomic analysis. The cellularity of human vertebral bone tissue was further analyzed using uniform manifold approximation and projection. Pseudo-time analysis and gene enrichment analysis revealed the biological function of cell fate and its counterparts. CellphoneDB was used to identify the interactions between bone cells and immune cells in the osteoimmune microenvironment of human vertebral bone tissue and their potential functions. Results: A cellular profile of the osteoimmune microenvironment of human vertebral bone tissue was established, including mesenchymal stem cells (MSCs), pericytes, myofibroblasts, fibroblasts, chondrocytes, endothelial cells (ECs), granulocytes, monocytes, T cells, B cells, plasma cells, mast cells, and early erythrocytes. MSCs play an immunoregulatory function and mediate osteogenic differentiation and cell proliferation. The differentiation trajectory of osteoclasts in human vertebral bone tissue was also revealed. In addition, ECs actively participate in inflammatory infiltration and coupling with bone cells. T and B cells actively participate in regulating bone homeostasis. Finally, by identifying the interaction of ligand-receptor pairs, we found that immune cells and osteoclasts have bidirectional regulatory characteristics, have the effects of regulating bone resorption by osteoclasts and promoting bone formation, and are essential for bone homeostasis. It is also highlighted that CD8-TEM cells and osteoclasts might crosstalk via CD160-TNFRSF14 ligand-receptor interaction. Conclusion: Our analysis reveals a differential landscape of molecular pathways, population composition, and cell-cell interactions during OVCF development into KD. OVCFs exhibit a higher osteogenic differentiation capacity, owing to abundant immune cells. Conversely, KD results in greater bone resorption than bone formation due to depletion of MSCs and a relatively suppressed immune system, and this immune imbalance eventually leads to vertebral avascular necrosis. The site of action between immune cells and osteoclasts is expected to be a new therapeutic target, and these results may accelerate mechanistic and functional studies of osteoimmune cell types and specific gene action in vertebral avascular necrosis and pathological bone loss diseases, paving the way for drug discovery.

17.
Water Sci Technol ; 65(2): 254-61, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22233903

RESUMO

The microbial community of a mesophilic lab-scale upflow anaerobic sludge blanket (UASB) reactor treating vitamin C biosynthesis wastewater at gradually elevated organic loading rates (OLRs) was characterized using 16S rDNA-based polymerase chain reaction-DGGE (denatured gradient gel electrophoresis) analysis. The DGGE fingerprints suggested that the elevated OLRs did not cause any significant changes in the microbial community. The predominant bacterial bands were affiliated with the Firmicutes (Clostridiales, four bands), Proteobacteria (Deltaproteobacteria, six bands), Bacteroidetes, and Synergistetes, respectively. All the archaeal bands were very similar to already known methanogenic species: Methanobacterium formicicum (two bands), Methanomethylovorans hollandica (one band) and Methanosaeta concilli (two bands), which belonged to the divisions Methanobacteria and Methanomicrobia, respectively.


Assuntos
Archaea/classificação , Ácido Ascórbico , Bactérias/classificação , Reatores Biológicos/microbiologia , Resíduos Industriais , Anaerobiose , Archaea/genética , Archaea/metabolismo , Bactérias/genética , Bactérias/metabolismo , Análise da Demanda Biológica de Oxigênio , Eletroforese em Gel de Gradiente Desnaturante , Ácidos Graxos Voláteis/metabolismo , Resíduos Industriais/análise , Metano/metabolismo , Nitrogênio/análise , Fosfatos/análise , Reação em Cadeia da Polimerase , RNA Arqueal/genética , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Esgotos/microbiologia , Sulfatos/análise , Eliminação de Resíduos Líquidos , Poluentes da Água/análise
18.
Environ Sci Pollut Res Int ; 29(54): 81256-81264, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35729393

RESUMO

Nitrogen fertilizer has considerable effects on soil carbon fluxes. However, the responses of soil CO2 emission to N fertilizer remain controversial. A field experiment was conducted to examine the effect of application of N fertilizer on soil CO2 emission in a maize (Zea mays L.) field in Northeast China. Soil CO2 emission was measured from May 2010 to April 2016. Soil CO2 emission during the growing season and non-growing season contributed 79.7-83.6% and 16.4-20.3%, respectively, to the total annual CO2 emission. Cumulative annual soil CO2 emissions were significantly higher in no-N addition treatment (CK) than that in N addition treatment (SU) from 2012/2013 to 2015/2016 (p < 0.05). Mean annual soil CO2 emission decreased on averaged by 21.2% after N fertilization (p < 0.05). 49.6-82.2% of CO2 flux variation was explained by soil temperature at 5 cm depth. Q10 of soil CO2 emission in the annual scale was not significantly affected by N fertilizer. The results highlight the importance of N fertilizer on soil CO2 emission in agricultural ecosystem.


Assuntos
Solo , Zea mays , Fertilizantes , Nitrogênio/análise , Dióxido de Carbono/análise , Ecossistema , Agricultura , China , Fertilização , Carbono , Óxido Nitroso/análise
19.
Microorganisms ; 10(3)2022 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-35336128

RESUMO

Laboratory animals with human microbiome have increasingly been used to study the role of bacteria and host interaction. Drosophila melanogaster, as a model of microbiota-host interaction with high reproductive efficiency and high availability, has always been lacking studies of interaction with human gut microbiome. In this study, we attempted to use antibiotic therapy and human fecal exposure strategy to transfer the human microbiome to the drosophila. The method includes depleting the original intestinal bacteria using a broad-spectrum antibiotic and then introducing human microorganisms by a diet supplemented with donor's fecal samples. The sequencing results showed that 80-87.5% of the OTUs (Operational Taxonomic Units) from donor feces were adopted by the recipient drosophila following 30 days of observation. In comparison to females, the male recipient drosophila inherited more microbiota from the donor feces and had significantly increased lifespan as well as improved vertical climbing ability. Furthermore, distinctly differential expression patterns for age and insulin-like signaling-related genes were obtained for the male vs. female recipients. Only the male drosophila offspring acquired the characteristics of the donor fecal microbiota.

20.
Sci Rep ; 12(1): 15202, 2022 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-36075952

RESUMO

The incorporation of animal manure (AM) in soil plays an essential role in soil carbon sequestration but might induce higher soil nitrous oxide (N2O) emissions. The use of nitrification inhibitors (NI) is an effective strategy to abate N2O emission in agro-ecosystems. However, very few studies have evaluated the effectiveness of applying NI under the combined application of organic and inorganic fertilizers for increasing soil carbon sequestration and reducing N2O emissions simultaneously in Northeast China. Here, a four-year field experiment was conducted with three treatments [inorganic fertilizer (NPK), inorganic fertilizer + manure (NPKM), and inorganic fertilizer with NI + manure (NPKI + M)], in a rainfed maize cropping system in Northeast China. Plots of different treatments were kept in the same locations for 4 years. Gas samples were collected using the static closed chamber technique, and nitrous oxide (N2O) concentration in gas samples was quantified using a gas chromatograph. Soil organic carbon sequestration rate (SOCSR) was calculated based on the changes in SOC from April 2012 to October 2015. Averaged over the four years, AM incorporation significantly increased soil N2O emissions by 25.8% (p < 0.05), compared to NPK treatment. DMPP (3,4-dimethylpyrazole phosphate) significantly decreased N2O emissions by 32.5% (p < 0.05) relative to NPKM treatment. SOC content was significantly elevated by 24.1% in the NPKI + M treatment than the NPK treatment after four years of manure application (p < 0.05). The annual topsoil SOCSR for the NPKM and NPKI + M treatments was 0.57 Mg ha-1 yr-1 and 1.02 Mg ha-1 yr-1, respectively, which were significantly higher than that of NPK treatment (- 0.61 Mg ha-1 yr-1, p < 0.05). AM addition significantly increased the aboveground biomass and crop yields of maize in the fourth year. Overall, combined application of DMPP, inorganic fertilizer and AM is strongly recommended in this rainfed maize cropping system, which can increase maize yield and SOC sequestration rate, and mitigate N2O emission.


Assuntos
Esterco , Solo , Agricultura/métodos , Animais , Carbono/análise , China , Iodeto de Dimetilfenilpiperazina , Ecossistema , Fertilizantes , Nitrificação , Nitrogênio/análise , Óxido Nitroso/análise , Solo/química , Triticum , Zea mays
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