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The laser scattering characteristic of pavement is one of the important factors that affect the detection performance of optical sensors such as lidars. Because the wavelength of laser does not match the roughness of the asphalt pavement, the common analytical approximation model of electromagnetic scattering is not applicable in this case, so it is difficult to calculate the laser scattering distribution of the pavement accurately and effectively. According to the self-similarity of the asphalt pavement profile, a fractal two-scale method (FTSM) based on fractal structure is proposed in this paper. We used the Monte Carlo method to obtain the bidirectional scattering intensity distribution (SID) and the back SID of the laser on the asphalt pavement with different roughness. Then we designed a laser scattering measurement system to verify the simulation results. We calculated and measured the SIDs of s-light and p-light of three asphalt pavements with different roughness (σ=0.34 mm; 1.74 mm; 3.08 mm). The results show that, compared with the traditional analytical approximation methods, the results of FTSM are closer to the experimental results. Compared with the single-scale model based on the Kirchhoff approximation, FTSM has a significant improvement in computational accuracy and speed.
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Ammonia-oxidising archaea (AOA) and ammonia-oxidising bacteria (AOB) are ammonium oxidising prokaryotes that can drive soil nitrification in wetlands. During the restoration of wetlands, different types of land use soils (agricultural soil [AS], restored wetland soil [RS], and natural wetland soil [NWS]) are present. However, studies on the effects of changes in the types of land use in wetlands during restoration on nitrification and the community composition of AOA and AOB are still not well understood. In this study, the differences in the potential nitrification rate (PNR) and community composition of AOA and AOB in AS, RS, and NWS were compared and discussed. The results indicated that the PNRs in the AS, RS, and NWS were on the same order of magnitude. Nitrification was mainly driven by AOB. High-throughput sequencing results showed that the genus Nitrososphaera of AOA and unclassified_o_Nitrosomonadales of AOB were only detected in the AS. Redundancy analysis (RDA) results indicated that the community composition of AOA was mostly influenced by pH, while TC was the most influential variable on the community composition of AOB. Our study provides a basis for distinguishing the roles of ammonium-oxidising prokaryotes in nitrification and further understanding the changes in nitrifying activity in wetlands during restoration.
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Compostos de Amônio/análise , Archaea/isolamento & purificação , Betaproteobacteria/isolamento & purificação , Microbiologia do Solo , Áreas Alagadas , Agricultura , DNA Arqueal/genética , DNA Bacteriano/genética , Sequenciamento de Nucleotídeos em Larga Escala , Nitrificação , Oxirredução , Filogenia , Análise de Sequência de DNA , Solo/químicaRESUMO
Denitrification is a key nitrogen removal process that involves many denitrifying bacteria. In this study, the denitrification performance was estimated for soil samples from different land use types including farmland soil, restored wetland soil, and wetland soil. The quantitative real-time polymerase chain reaction results showed that the average abundance of nirS and nirK genes was notably affected by seasonal changes, increasing from 2.34 × 10 6 and 2.81 × 10 6 to 1.97 × 10 6 and 4.55 × 10 6 gene copies/g of dry soil, respectively, from autumn to spring. This suggests that the abundance of nirS and nirK denitrifiers in spring is higher than those in autumn. Furthermore, the abundance of nirS and nirK genes was higher in the farmland soil than in restored wetland soil and wetland soil in both seasons. According to the analyses of MiSeq sequencing of nirS and nirK genes, Halobacteriaceae could be used as a special strain to distinguish wetland soil from farmland soil and restored wetland soil. Furthermore, redundancy analysis indicated that the soil environmental variables of total carbon, total nitrogen, moisture content, and organic matter were the main factors affecting the community structures of nirS and nirK denitrifiers existing in wetland soil. These findings could contribute to understanding the differences in nirS and nirK denitrifiers between different land use types during seasonal changes.
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Bactérias/classificação , Bactérias/metabolismo , Desnitrificação/genética , Microbiologia do Solo , Bactérias/genética , Bactérias/isolamento & purificação , Biodiversidade , China , Fazendas , Genes Bacterianos/genética , Nitrito Redutases/genética , Estações do Ano , Solo/química , Áreas AlagadasRESUMO
The splicing factor SPF45 (RBM17) is a well-known component of the spliceosome that is involved in alternative splicing. RBM17 is frequently overexpressed in many tumors and plays a crucial role in cancer progression and drug resistance. However, the role of RBM17 in the development of glioma has not been thoroughly elucidated to date. In the present study, we found that RBM17 was overexpressed in glioma and that a high level of expression of RBM17 was closely associated with a poor prognosis in glioma patients. We investigated the effect of RBM17 on apoptosis, cell growth and cell cycle indexes and the activation of apoptosis signaling by shRNA in human U87 and U251 glioma cells. The downregulated expression of RBM17 mRNA was accompanied by the induction of cell cycle arrest, and apoptosis, reduced cell proliferation in the two cell lines, and reduced cell survival, as measured by the increased activation of caspase-3, caspase-9, and PARP (poly ADP-ribose polymerase). Furthermore, in subcutaneous U87â¯cell xenograft tumors in nude mice, intradermal administration of an shRNA targeting RBM17 significantly downregulated RBM17 expression in vivo and was accompanied by the suppressed growth of glioma. To the best of our knowledge, our results are the first to confirm that RBM17 functions in promoting cell proliferation, affecting the cell cycle, and inducing apoptosis in human glioma cells both in vitro and in vivo. These results indicate that RBM17 may be a therapeutic target in the clinical management of glioma.
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Apoptose/genética , Neoplasias Encefálicas/genética , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Glioma/genética , Fatores de Processamento de RNA/genética , Animais , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Pontos de Checagem do Ciclo Celular/genética , Linhagem Celular Tumoral , Progressão da Doença , Glioma/metabolismo , Glioma/patologia , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Prognóstico , Interferência de RNA , Fatores de Processamento de RNA/metabolismo , Análise de Sobrevida , Transplante HeterólogoRESUMO
This paper investigates the signal to interference plus noise ratio (SINR) performance of the imaging laser radar (ILR) system operating at a wavelength of 905 nm using an avalanche photodiode array under the fog condition. We analysis the glow image of the light source, which is formed by the laser spot irradiated on a standard Lambertian target. Based on the proposed theoretical model, we determine the interference due to the glow inter-channel crosstalk under different fog conditions for a targeted channel. We show that, for transmission spans less than several tens of meters the interference due to glow crosstalk is higher than the fog (light to medium) induced losses. However, for a link range longer than 21 m the glow crosstalk induced interference is lower than the heavy fog induced attenuation. The proposed system performance is evaluated by developing an experimental test bed and using a dedicated indoor atmospheric chamber under homogeneously controlled fog conditions. We show that, under different fog conditions experimental results for changing SINR levels match well with the predicted data. The results shown can be used for design optimization of the ILR system when operated under fog conditions.
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For a laser radar (LADAR) system using a Geiger-mode avalanche photodiode (GmAPD), attenuating echo and background noise simultaneously affect the original data output from the GmAPD and eventually affect detection performance. In this study, we established a model that applies to the GmAPD-based LADAR with optical attenuation and also applies to any typical single photon detector that has a dead time (e.g., the photomultiplier tube); thus, a comprehensive and fundamental study is performed for the mathematical expectation of the number of signal detections (ES), the mathematical expectation of the number of noise detections (EN), the signal-to-noise ratio (SNR), and the range bias (absolute error, Rb) and precision (standard deviation, Rp) under various attenuation levels with different dead times and signal noise conditions. We observed the following: on the one hand, there exists an optimum attenuation level at which ES and SNR are maximized; on the other hand, there exists another optimum attenuation level for shorter dead times, at which Rp is minimized. The phenomenon of the maximum ES, SNR, or minimum Rp disappears gradually as the echo or noise decreases from high levels (e.g., 10 photoelectrons/echo or an equivalent background noise of 10 photoelectrons/range gate). Further, higher attenuation, which shows advantages under strong echo or noise conditions, yields a larger improvement in ES for longer dead times; and, with the reduction of the dead time or the noise, the maximum ES gradually increases, and the corresponding optimum attenuation level becomes slighter. Additionally, we found that, as the optical attenuation increases, EN decreases to 0, Rb changes from a negative value to 0, and Rp is minimized, becomes slightly worse, and reaches a constant. Moreover, the shorter dead times, which show advantages when they are shorter than the end time of the echo, lead to a larger ES, better Rb, and slightly worse Rp than the longer ones.
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The waveform fitting technique has been a prevailing method for accurate extraction of a range of objects from an observed signal. Exploration of range precision then became a significant research topic to evaluate the performance of the technique with the corruption of noise. In this paper, we derive an analytical solution of the maximum likelihood estimation for the Gaussian model as the probability density function (PDF) of the range estimator. The variance of the linear version of the PDF is consistent with the Cramer-Rao bound (CRB). Thus, the variance of the PDF is regarded as the theoretical range precision (TRP) compared with the CRB. The verification results show the TRP can perfectly describe the variance of the simulation data while the CRB provides a lower bound. At a higher signal-to-noise ratio (SNR), both the TRP and CRB have the ability to provide an accurate description of the range precision. At a lower SNR, the TRP still performs well while the CRB is too loose to bound the variance on the unbiased estimation.
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Dead-time has a significant influence on the detection efficiency and range performance of a photon-counting laser radar system with a Geiger-mode avalanche photodiode. In this paper, a rapid universal recursive model of the detection probability of discrete time under various dead-times is proposed, which is verified with controlled parameters. Our model has the advantage of fast computing speed and unifies multi-trigger, single-trigger, and zero-dead-time models. The computing speed is 1 to 2 orders of magnitude faster than Gatt's and Zhao's models under a short dead-time condition, with relative errors less than 0.001 and 10-14, respectively. Subsequently, the detection efficiency and range bias and precision with various dead-times are theoretically calculated and Monte Carlo simulated with different parameters. On the one hand, dead-time shorter than the end time of the target achieves better detection efficiency; however, this results in worse range performance. On the other hand, dead-time longer than the end time of the target maintains the detection efficiency at a low level but provides a better range performance. We discover that noise is the key reason for the periodic fluctuation of the detection efficiency and range performance versus different dead-times and the local optimum values of fluctuations occur when the dead-time is a few nanoseconds shorter or longer than 1, 1/2, 1/3, or even 1/4 of the end time of the target; further, this phenomenon becomes more evident when noise increases. Moreover, weaker noise level is crucial to the detection efficiency, and narrow pulse width and nearer target position in the range gate are important factors to improve precision.
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We investigate the multiple attribute decision-making (MADM) problems with hesitant triangular fuzzy information. Firstly, definition and some operational laws of hesitant triangular fuzzy elements are introduced. Then, we develop some hesitant triangular fuzzy aggregation operators based on Bonferroni means and discuss their basic properties. Some existing operators can be viewed as their special cases. Next, we apply the proposed operators to deal with multiple attribute decision-making problems under hesitant triangular fuzzy environment. Finally, an illustrative example is given to show the developed method and demonstrate its practicality and effectiveness.
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Simulação por Computador , Tomada de Decisões Assistida por Computador , Algoritmos , Lógica Fuzzy , Modelos TeóricosRESUMO
Current studies have elaborated diabetes mellitus as one of the most prevalent endocrine disorder throughout the world. Citrullus colocynthis (C. colocynthis) is one of the most common traditional plants used as remedy against diabetes mellitus. It is well recognized by its hypoglycemic effect, which is substantiated in current phytotherapy. Its undesired effects include the disturbance of gastrointestinal and urinary tracts. This review article encompasses various blood glucose lowering studies that have been carried out till date. Various parts of plants used in extract preparation were roots, fruits, seeds, rinds and leaves. The nature of these extracts was ethnolic, methanolic, or aqueous and their doses varied from 10 to 500 mg/kg body weight/day. All these published articles elaborate C. colocynthis as a potential antiglycemic medicinal plant.
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Citrullus , Diabetes Mellitus/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Extratos Vegetais/uso terapêutico , Animais , Biomarcadores/sangue , Glicemia/efeitos dos fármacos , Glicemia/metabolismo , Diabetes Mellitus/sangue , Humanos , Hipoglicemiantes/efeitos adversos , Fitoterapia , Extratos Vegetais/efeitos adversos , Plantas MedicinaisRESUMO
This study discussed the effects of different concentrations (0.625, 1.875 and 3.125 mM) of copper (Cu) in the form of CuSO4 on biomethane production and on the dynamics of microbial communities during the mesophilic anaerobic digestion (AD) of cow manure. The effects on biomethane production were found to depend on CuSO4 concentrations. After 50 days of AD, treatment A3 (3.125 mM) had lower cumulative biomethane production than the no-Cu control. The maximum value of cumulative biomethane production was detected under treatment A2 (1.875 mM). These results suggested that the stimulation or inhibition to biomethane production might be related to the concentration and chemical forms of Cu. Moreover, polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) was used to discuss the dynamics of microbial communities. Results revealed that different concentrations of CuSO4 had effects on the richness and diversity of bacterial and archaeal communities. The predominance of Bacteroidetes bacterium (GU339485.1) was verified through the sequencing of the dominant DGGE bands. Furthermore, Bacteroidetes bacterium could be detected during the whole AD process and is adaptable to a certain concentration range of CuSO4.
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Archaea/metabolismo , Bactérias/metabolismo , Biocombustíveis/análise , Sulfato de Cobre/metabolismo , Metano/biossíntese , Anaerobiose/efeitos dos fármacos , Animais , Archaea/efeitos dos fármacos , Archaea/genética , Bactérias/efeitos dos fármacos , Bactérias/genética , Reatores Biológicos/microbiologia , Bovinos , Eletroforese em Gel de Gradiente Desnaturante , Relação Dose-Resposta a Droga , Fermentação , Esterco/microbiologia , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase , RNA Arqueal/genética , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Análise de Sequência de DNARESUMO
Microbial community in wetland soils is crucial for maintaining the stability of the wetland ecosystem. Nevertheless, the soil microbial community is sensitive to the environmental stress in wetlands. This leads to the possibility that the microbial community structure may be influenced by environmental factors. To gain an in-depth understanding in the response of microbial community structure in wetland soils under different environmental factors, this review comprehensively explores the factors of natural conditions (e.g., different types of wetland, soil physical and chemical properties, climate conditions), biological factors (e.g., plants, soil animals), and human activities (e.g., land use, soil pollution, grazing). Those factors can affect microbial community structure and activities in wetland soils through different ways such as (i) affecting the wetland soil environment in which soil microorganisms survived in, (ii) influencing the available nutrients (e.g., carbon, nitrogen) required for microbial activity, and (iii) the direct effects on soil microorganisms (toxicity or promotion of resistant species). This review can provide references for the conservation of microbial diversity in wetland soils, the maintenance of wetland ecosystem balance, and the wetland ecological restoration.
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Microbiologia do Solo , Solo , Áreas Alagadas , Solo/química , Microbiota , EcossistemaRESUMO
The post-release performance of cultured fish is crucial for understanding the viability of cultured fish and assessing the effects of stock enhancement programs. This study aimed to investigate the initial post-release performance of cultured Cyprinus chilia juveniles by examining their movement, spatial distribution, gut fullness, and gut microbiota in nature. In July 2022, a total of 20,000 C. chilia juveniles, tagged with visible implant fluorescence (VIE), were released into Qilu Lake, a shallow lake in southwestern China. Subsequently, continuous recapture was conducted at fixed recapture sites using trap nets during the first 7 days, one month and three months after release. Out of the released fish, 512 were recaptured, resulting in a recapture rate of 2.56%. The recaptured fish had a 100% tag retention rate. The majority (98.05%) of the recaptured fish were found in the recapture sites located on the eastern or western lakeshore, while only 10 fish were recaptured from the recapture sites in the northern lake area. The water depth range where the recaptured fish were found ranged from 190 to 350 cm, with most fish preferring depths less than 300 cm. The majority of the released fish migrated towards the eastern and western lakeshore, with long-distance movement (greater than 100 m) primarily occurring within the first four days after release. The level of gut fullness in the released fish initially decreased and then increased over time following release. Regarding gut microbiota, the dominant phyla observed in most samples were Firmicutes, Proteobacteria, Cyanobacteria, and Fusobacteria. Furthermore, significant variations in the dominant genera were observed across different samples. Principal coordinates analysis (PCoA) revealed clear separation between the microbial communities of pre-release and post-release C. chilia juveniles. This study demonstrated that VIE tagging was a suitable method for short-term marking of C. chilia juveniles. Lakeshores with water depths less than 300 cm were identified as preferred habitats for C. chilia juveniles. The primary adaptation period for cultured C. chilia juveniles released into the natural environment was found to be approximately 4-5 days. These findings contribute to our understanding of the post-release performance of cultured fish and may provide guidance for the management and evaluation of relevant stock enhancement programs.
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PURPOSE: Obstructive sleep apnea (OSA) is primarily characterized by repetitive episodes of complete or partial obstruction of airflow during sleep. The neuronal and cellular mechanisms underlying this process are not fully understood, although the focus of some studies is on putative serotonin (5-HT) mechanisms, and serotonergic therapy may be beneficial to OSA patients. This study aimed to demonstrate possible changes in 5-HT associated with induction of OSA in a rat model. METHODS: Apnea was induced in rats by injection of L-glutamate (L-Glu) into the insular cortex. We examined changes in: (1) simultaneous genioglossus and diaphragm EMG activity; and (2) peripheral and cerebral levels of 5-HT, by histology. RESULTS: Injection of L-glutamate (L-Glu) into the insular cortex induced apnea in the rats. L-Glu stimulation of the insular cortex also produced significant reductions in plasma 5-HT levels and the expression of 5-HT in the brainstem. In addition, lower activity was observed in the GG and a higher activity was observed in the diaphragm, as compared to controls. CONCLUSION: Data indicate that L-Glu stimulation of the insular cortex simulates the electrical activity of the genioglossus muscle and diaphragm in sleep apnea, and contributes to reduced peripheral and cerebral 5-HT levels in rats. The results of our study suggest that 5-HT may play a role in the pathogenesis of OSA.
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Córtex Cerebral/efeitos dos fármacos , Modelos Animais de Doenças , Ácido Glutâmico/farmacologia , Serotonina/sangue , Apneia Obstrutiva do Sono/induzido quimicamente , Animais , Tronco Encefálico/efeitos dos fármacos , Tronco Encefálico/patologia , Córtex Cerebral/patologia , Eletromiografia/efeitos dos fármacos , Feminino , Injeções , Masculino , Ratos , Ratos Wistar , Respiração/efeitos dos fármacos , Apneia Obstrutiva do Sono/sangue , Apneia Obstrutiva do Sono/patologiaRESUMO
OBJECTIVE: This study aims to examine the impact of chronic intermittent hypoxia on hearts in patients with obstructive sleep apnea (OSA). METHODS: Two hundred twenty patients were divided into groups based on (1) severity of the disease, (2) years of disease history, and (3) with or without secondary hypertension. All subjects underwent blood pressure measurements, polysomnogram monitoring, and cardiac Doppler ultrasound examinations. RESULTS: The left ventricular ejection fraction (LVEF), fractional shortening (FS), and the ratio of early to late diastolic filling (E/A) in patients with severe OSA were lower than in those with moderate OSA and in healthy controls. The inner diameters of the main pulmonary artery (inD of MPA), the inner diameters of the right cardiac ventricle (inD of RV), and the thickness of anterior wall of the right ventricle (TAW of RV) were increased in patients with severe OSA compared to those with moderate disease and worsened as a function of time with disease. The tissue Doppler imaging-derived Tei index and pulmonary artery systolic pressure were also increased along with the severity of OSA. LVEF and FS in patients who had suffered from OSA for >10 years were decreased compared with those suffering from OSA for a shorter time. LVEF and FS in patients with secondary hypertension were decreased significantly relative to non-hypertensive OSA patients and healthy controls. E/A was decreased in OSA patients whether they had secondary hypertension or not. CONCLUSION: OSA affected the left ventricular diastolic function in the early stage of the disease. Extended exposure to OSA resulted in left ventricular dysfunction with increased hypertension. Right ventricle dysfunction and abnormalities became more severe as the disease progressed.
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Hemodinâmica/fisiologia , Hipóxia/fisiopatologia , Apneia Obstrutiva do Sono/complicações , Apneia Obstrutiva do Sono/fisiopatologia , Disfunção Ventricular Esquerda/fisiopatologia , Disfunção Ventricular Direita/fisiopatologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Consumo de Bebidas Alcoólicas/efeitos adversos , Consumo de Bebidas Alcoólicas/fisiopatologia , Índice de Massa Corporal , Progressão da Doença , Ecocardiografia , Técnicas de Imagem por Elasticidade , Feminino , Humanos , Hipertensão/diagnóstico , Hipertensão/fisiopatologia , Hipóxia/diagnóstico , Masculino , Pessoa de Meia-Idade , Oxigênio/sangue , Polissonografia , Valores de Referência , Apneia Obstrutiva do Sono/diagnóstico , Fumar/efeitos adversos , Fumar/fisiopatologia , Volume Sistólico/fisiologia , Disfunção Ventricular Esquerda/diagnóstico , Disfunção Ventricular Direita/diagnósticoRESUMO
OBJECTIVE: To investigate the influence of left heart function in obstructive sleep apnea by CIH, and explore left heart function and blood pressures before or after CPAP. METHODS: 75 OSA were divided into two groups: 40 patients blood pressures were coincident with diagnostic standard of hypertension recording; 35 patients blood pressures were non-hypertension recording. The control group included 30. healthy adults. The blood pressures before and also after sleep, left ventricular ejection fraction (LVEF), shortening fraction (FS), E, A and E/A were compared with those of normal control subjects. Analyzed BP, LVEF and E/A after CPAP. RESULTS: (1) The blood pressure soon after getting up in the morning (150.80+/-20.73/108.0+/-15.34) mm Hg (1 mm Hg=0.133 kPa) was significantly higher than that before sleep (134.16+/-18.33/90.09+/-11.24) mm Hg (P<0.001). (2) Multiple parameters including LVEF, FS and E/A, were impaired in OSA patients relative to the control subjects (P<0.05 or P<0.01), OSA affected cardiovascular function directly; E/A was significantly decreased in obstructive sleep apnea unallied hypertension than that in normal control subjects; E/A was conspicuously decreased in obstructive sleep apnea associated hypertension comparing with that in obstructive sleep apnea unallied hypertension. These showed OSA affected cardiovascular function directly, hypertension aggravated the drop in cardiovascular function. 3. After CPAP in 6 months, it (142.59+/-15.34/96.52+/-9.81) mm Hg was significantly decreased than that before treatment (150.80+/-20.73/108.0+/-15.34) (P<0.001); LVEF (59.70+/-11.1)% was increased than that before treatment (56.40+/-9.74)% (P<0.05) and E/A 1.16+/-0.25 was increased. Than that before treatment 0.87+/-0.17 (P<0.01). CONCLUSION: (1) CIH may affect left heart structure and function; these changes were aggravated with hypertension. (2) CPAP treatment had important sense in the treatment of hypertension and cardiovascular function, and improved the life quality.
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Pressão Sanguínea , Hipertensão/fisiopatologia , Hipóxia/diagnóstico por imagem , Hipóxia/fisiopatologia , Apneia Obstrutiva do Sono/fisiopatologia , Adulto , Idoso , Estudos de Casos e Controles , Pressão Positiva Contínua nas Vias Aéreas , Ecocardiografia Doppler em Cores , Feminino , Frequência Cardíaca , Humanos , Masculino , Pessoa de Meia-Idade , Apneia Obstrutiva do Sono/diagnóstico por imagem , Função Ventricular EsquerdaRESUMO
A novel route is developed for regeneration of deactivated commercial NH3-SCR catalysts, which includes an initial in situ construction of anatase TiO2 porous film, followed by loading of MnOx, CeOx, and Mn-Ce mixed oxides as active components. The regenerated catalysts present largely improved low-temperature denitrification performance due to the synergetic effect of MnOx and CeOx. The denitrification efficiency could reach a high value of 97% at 200 °C and 100% at 250 °C when the Ce-Mn mixed oxides are loaded at the optimized molar quantity ratio of 10:9 (Ce:Mn). Properties and reaction mechanisms of the regenerated catalysts are investigated with characterizations of X-ray photoelectron spectroscopy (XPS), NH3 temperature-programmed desorption (NH3-TPD), H2 temperature-programmed reduction (H2-TPR), and in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS). Our results demonstrate that the adsorption and oxidation of NO plays a crucial role for these three catalysts even though a difference exists on the reaction pathways. Graphical abstract.
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Amônia , Temperatura Baixa , Catálise , Oxirredução , Óxidos , TemperaturaRESUMO
Aim: This study aimed to identify the independent risk factors of recurrence in patients undergoing primary resection of meningioma and construct a scoring system for the prediction of the risk of postoperative recurrence. Materials and Methods: The clinical data of 591 patients who underwent primary surgical resection for meningioma at the First Affiliated Hospital of Wenzhou Medical University between November 2010 and December 2016 were retrospectively reviewed. The clinical, radiological, and pathological characteristics were evaluated, and the independent risk factors for recurrence were identified via receiver operating characteristic (ROC) curve and logistic analyses. A scoring system that included these independent risk factors was used to construct a risk-predicting model that was evaluated via a ROC curve analysis. The recurrences of different subgroups were observed by Kaplan-Meier's curves. Results: The clinical data of 392 patients with meningioma were used to construct the scoring system. The logistic analysis showed that sex (OR = 2.793, 95% CI = 1.076-7.249, P = 0.035), heterogeneous tumor enhancement (OR = 4.452, 95% CI = 1.714-11.559, P = 0.002), brain invasion (OR = 2.650, 95% CI = 1.043-6.733, P = 0.041), Simpson's removal grade (OR = 5.139, 95% CI = 1.355-19.489, P = 0.016), and pathological grade (OR = 3.282, 95% CI = 1.123-9.595, P = 0.030) were independent risk factors for recurrence. A scoring system was developed and used to divide the patients into the following four subgroups: subgroup 1 with scores of 0-75 (n = 249), subgroup 2 with scores of 76-154 (n = 88), subgroup 3 with scores of 155-215 (n = 46), and subgroup 4 with scores of 216-275 (n = 9). The incidences of recurrence in each subgroup were as follows: subgroup 1, 1.2%; subgroup 2, 5.7%; subgroup 3, 26.1%; and subgroup 4, 66.7% (P < 0.001). The scoring system reliably predicted the postoperative recurrence of meningioma with a high area under the ROC curve. Conclusions: Our scoring system is a simple and reliable instrument for identifying meningioma patients at risk of postoperative recurrence and could help in optimizing individualized clinical treatment.
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OBJECTIVE: To investigate the effects of obstructive sleep apnea-hypopnea syndrome (OSAHS) upon cardiac structure and function of patients. METHODS: According to apnea hypopnea index, 75 OSAHS patients were divided into three groups: mild (n = 25), moderate (n = 25) and serious (n = 25); according to the course of disease, < 5 years (n = 22), 5-10 years (n = 26) and > 10 years (n = 27). The control group included 25 healthy adults. All subjects received polysomnogram and echocardiography. The following parameters were recorded: aortic dimension, pulmonary artery inner diameter, chambers heart size, interventricular septal thickness, anterior wall thickness and movement extent of end-diastole right ventricle, left ventricular ejection fraction (LVEF), shortening fraction (FS) and E/A ratio, etc. RESULTS: Pulmonary artery inner diameter of mild, moderate, serious and control groups were (21.4 +/- 2.5), (24.7 +/- 2.0), (26.7 +/- 2.1), (21.2 +/- 2.7) mm, right ventricle internal diameter (19.0 +/- 1.8), (22.0 +/- 2.1), (23.9 +/- 2.1), (18.9 +/- 1.8) mm, and anterior wall thickness of right ventricle (4.7 +/- 1.2), (6.5 +/- 1.3), (7.5 +/- 1.4), (4.1 +/- 1.0) mm. The moderate and serious groups were all higher than control and mild groups obviously (P < 0.01). The serious group was higher than the moderate group (P < 0.01). LVEF of four groups: (63.1 +/- 8.1)%, (60.0 +/- 10.2)%, (54.5 +/- 9.1)%, (63.6 +/- 7.7)%, FS: (38.1 +/- 4.3)%, (37.0 +/- 6.4)%, (33.6 +/- 5.4)%, (39.5 +/- 4.9)%, and E/A: (1.13 +/- 0.13), (0.96 +/- 0.16), (0.85 +/- 0.12), (1.28 +/- 0.15). LVEF and FS of the serious group were lower than those of the control, mild and moderate groups (P < 0.05). E/A ratio of the mild, moderate and serious groups were lower than the control group (P < 0.01). The interclass comparison of mild, moderate and serious groups had significant differences (P < 0.01). Right ventricle internal diameter, pulmonary artery inner diameter, anterior wall thickness of right ventricle of > 10 years group were higher than 5-10 years group obviously (P < 0.05, P < 0.01). The 5-10 years group was higher than the < 5 years and control groups obviously (P < 0.05, P < 0.01). LVEF, FS, and E/A ratio of > 10 years group were lower than 5-10 years, < 5 years and control groups obviously (P < 0.05, P < 0.01). CONCLUSION: OSAHS causes structural and functional cardiac changes worsening with disease aggravation and course extension.
Assuntos
Coração/fisiopatologia , Apneia Obstrutiva do Sono/diagnóstico por imagem , Apneia Obstrutiva do Sono/fisiopatologia , Adulto , Idoso , Estudos de Casos e Controles , Ecocardiografia , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
The biotransformation of hexavalent chromium [Cr(VI)] via Cr(VI)-reducing microorganisms is considered an ecofriendly approach to detoxify Cr(VI). A new Cr(VI)-reducing bacterium named Microbacterium sp. QH-2 was isolated in this study. Scanning electron microscopy (SEM) images showed protrusions on the bacterial surface of strain QH-2 after an 18 h incubation in media under 10 mM Cr(VI) treatment. Results of the experiments on the capacity of reducing Cr(VI) indicated that strain QH-2 could reduce 100% Cr(VI) less than 48-96 h. When media with 4 mM Cr(VI) were incubated, the fastest reduction rate of strain QH-2 could come up to 2.17 mg/L Cr(VI) h-1. Furthermore, strain QH-2 could reduce Cr(VI) over the pH between 7 and 10. The optimum pH to reduce Cr(VI) by strain QH-2 was 9. Strain QH-2 also exhibited a relatively high tolerance even to 20 mM Cr(VI). These results declared that strain QH-2 had the potential to detoxify Cr(VI) in the Cr(VI)-contaminated soil or effluent.