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1.
Small ; : e2407896, 2024 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-39473323

RESUMO

As a novel energy harvesting technology, bettering the output performance of triboelectric nanogenerators (TENGs) is vital. Although quite a number methods to increase charge density have been proposed, challenges such as high impedance matching and low output current persist, severely limit the energy utilization efficiency of TENGs. Here, a new power management circuit (PMC) is proposed that through charge storage and release strategy. This circuit first excites the surface charge of the TENG using the charge excitation circuit, and then releases the stored charge through a self-triggered switch. Compared to a standard TENG, the output current of the TENG with this PMC is increased by a factor of 1108, the impedance is decreased from 100 MΩ to 10 kΩ, and the energy utilization efficiency is markedly improved. This work affords a reference for enhancing the output performance of TENG, reducing impedance, and broading the utility attainable of TENGs.

2.
Fish Shellfish Immunol ; 150: 109635, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38754648

RESUMO

The present study explored the effects of different lipid sources on growth performance, lipid deposition, antioxidant capacity, inflammatory response and disease resistance of largemouth bass (Micropterus salmoides). Four isonitrogenous (crude protein 50.46 %) and isolipidic (crude lipid 11.12 %) diets were formulated to contain 7 % of different oil sources including fish oil (FO) (control), soybean oil (SO), linseed oil (LO) and coconut oil (CO). Largemouth bass with initial body weight of 36.0 ± 0.2 g were randomly distributed into 12 tanks, with 30 fish per tank and 3 tanks per treatment. The fish were fed with the experiment diets twice daily for 8 weeks. The results indicated that the weight gain of largemouth bass fed the FO diet was significantly higher than that of fish fed the LO and CO diets. The liver crude lipid content in FO group was significantly higher than other groups, while the highest liver triglyceride content was showed in SO group and the lowest was detected in LO group. At transcriptional level, expression of lipogenesis related genes (pparγ, srebp1, fas, acc, dgat1 and dgat2) in the SO and CO group were significantly higher than the FO group. However, the expression of lipolysis and fatty acids oxidation related genes (pparα, cpt1, and aco) in vegetable oils groups were significantly higher than the FO group. As to the antioxidant capacity, vegetable oils significantly reduced the malondialdehyde content of largemouth bass. Total antioxidant capacity in the SO and LO groups were significantly increased compared with the FO group. Catalase in the LO group was significantly increased compared with the FO group. Furthermore, the ER stress related genes, such as grp78, atf6α, atf6ß, chop and xbp1 were significantly enhanced in the vegetable oil groups compared with the FO group. The activity of serum lysozyme in vegetable oil groups were significantly higher than in FO group. Additionally, the relative expression of non-specific immune related genes, including tlr2, mapk11, mapk13, mapk14, rela, tgf-ß1, tnfα, 5lox, il-1ß and il10, were all significantly increased in SO and CO groups compared to the other groups. In conclusion, based on the indexes including growth performance, lipid deposition, antioxidant capacity and inflammatory response, SO and LO could be alternative oil sources for largemouth bass.


Assuntos
Ração Animal , Antioxidantes , Bass , Dieta , Metabolismo dos Lipídeos , Animais , Bass/imunologia , Bass/crescimento & desenvolvimento , Dieta/veterinária , Ração Animal/análise , Antioxidantes/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Distribuição Aleatória , Suplementos Nutricionais/análise , Gorduras na Dieta/administração & dosagem , Óleos de Peixe/administração & dosagem , Óleo de Semente do Linho/administração & dosagem , Doenças dos Peixes/imunologia , Inflamação/veterinária , Inflamação/imunologia , Óleo de Soja/administração & dosagem , Óleo de Coco/administração & dosagem
3.
Mol Biol Rep ; 51(1): 776, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38904879

RESUMO

BACKGROUND: Traumatic hemorrhagic shock (THS) is a complex pathophysiological process resulting in multiple organ failure. Intestinal barrier dysfunction is one of the mechanisms implicated in multiple organ failure. The present study aimed to explore the regulatory role of mitogen-activated protein kinase kinase 3 (MKK3) in THS-induced intestinal injury and to elucidate its potential mechanism. METHODS: Rats were subjected to trauma and hemorrhage to establish a THS animal model. MKK3-targeted lentiviral vectors were injected via the tail vein 72 h before modeling. Twelve hours post-modeling, the mean arterial pressure (MAP) and heart rate (HR) were monitored, and histological injury to the intestine was assessed via H&E staining and transmission electron microscopy. Mitochondrial function and mitochondrial reactive oxygen species (ROS) were evaluated. IEC-6 cells were exposed to hypoxia to mimic intestinal injury following THS in vitro. RESULTS: MKK3 deficiency alleviated intestinal injury and restored mitochondrial function in intestinal tissues from THS-induced rats and hypoxia-treated IEC-6 cells. In addition, MKK3 deficiency promoted Sirt1/PGC-1α-mediated mitochondrial biogenesis and restricted Pink1/Parkin-mediated mitophagy in the injured intestine and IEC-6 cells. Furthermore, the protective effect of MKK3 knockdown against hypoxia-induced mitochondrial damage was strengthened upon simultaneous LC3B/Pink1/Parkin knockdown or weakened upon simultaneous Sirt1 knockdown. CONCLUSION: MKK3 deficiency protected against intestinal injury induced by THS by promoting mitochondrial biogenesis and restricting excessive mitophagy.


Assuntos
Intestinos , MAP Quinase Quinase 3 , Mitocôndrias , Espécies Reativas de Oxigênio , Choque Hemorrágico , Animais , Masculino , Ratos , Linhagem Celular , Modelos Animais de Doenças , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Intestinos/patologia , MAP Quinase Quinase 3/metabolismo , MAP Quinase Quinase 3/genética , Mitocôndrias/metabolismo , Mitofagia , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Choque Hemorrágico/complicações , Choque Hemorrágico/metabolismo , Choque Hemorrágico/genética , Choque Traumático/metabolismo , Choque Traumático/complicações , Choque Traumático/genética
4.
J Biochem Mol Toxicol ; 38(1): e23608, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38084607

RESUMO

This study aimed to explore the impact of different pH values of resuscitation fluid on traumatic hemorrhagic shock (THS), focusing on their effects on glycocalyx and inflammation. A rat model of THS was induced by hemorrhage from a left femur fracture, while an oxygen-glucose deprivation/reoxygenation (OGD/R)-induced HULEC-5a cell model was considered as an in vitro THS model. The lung tissue pathology and glycocalyx structure were assessed through hematoxylin-eosin (H&E) staining and transmission electron microscope examination. The levels of glycocalyx-related factors and inflammation-related factors were determined by enzyme-linked immunosorbent assay (ELISA). The expression of glycocalyx-related proteins, cell junction-related proteins, and proteins involved in the PI3K/Akt/NF-κB signaling pathway was analyzed by western blot. The results showed that both sodium bicarbonate Ringer's solution (BRS) and lactate Ringer's solution (LRS) were effective in restoring mean arterial pressure and heart rate in THS rats. However, LRS has a stronger impact on promoting inflammation and damaging the glycocalyx compared with BRS. In OGD/R-induced HULEC-5a cells, a pH of 7.4 and 6.5 increased inflammation and disrupted the glycocalyx, while a pH of 8.1 had no significant effect on inflammation or glycocalyx. Furthermore, the PI3K/Akt/NF-κB signaling pathway was activated by fluid resuscitation and different pH values. However, the activating effect of BRS and pH 8.1 on the PI3K/Akt/NF-κB signaling pathway was milder compared with LRS and pH6.5. In conclusion, an alkaline recovery environment was more beneficial for the treatment of THS.


Assuntos
Lesão Pulmonar , Choque Hemorrágico , Ratos , Animais , Choque Hemorrágico/tratamento farmacológico , Choque Hemorrágico/metabolismo , Choque Hemorrágico/patologia , Solução de Ringer , Soluções Isotônicas/química , Soluções Isotônicas/farmacologia , Bicarbonato de Sódio , Proteínas Proto-Oncogênicas c-akt , NF-kappa B/metabolismo , Fosfatidilinositol 3-Quinases , Ratos Sprague-Dawley , Hemorragia , Lactato de Ringer , Inflamação , Modelos Animais de Doenças
5.
BMC Med Educ ; 24(1): 229, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38439054

RESUMO

BACKGROUND: To characterize the current state of emergency medicine (EM) and the requirements for advancing EM clinical practice, education and research in China. METHODS: An anonymous electronic survey was conducted by Chinese Society of Emergency Medicine during September to October 2021. The survey contained 30 questions divided into 2 sections: the current state of EM development and the requirements for EM growth. RESULTS: 722 hospitals were included, of 487 were Level III and 235 were Level II hospitals. We found that after 40 years of development, EM had established a mature disciplinary system and refined sub-specialties including critical care, cardiopulmonary resuscitation, toxicology, disaster and emergency rescue. In Level III hospitals, 70.8% of EDs were standardized training centers for EM residents, but master's degree program, Doctor Degree program and post-doctoral degree program was approved in only 37.8%, 8.4% and 2.9% of EDs respectively and postgraduate curriculum was available in 1/4 of EDs. Only 8% have national or provincial key laboratories. In addition to advance clinical practice, there was also a high demand to improve teaching and research capacities, mainly focusing on literature review, research design and delivery, paper writing, residency training. CONCLUSIONS: EM has built a mature discipline system and refined sub-specialties in China. Teaching and research developed parallel with clinical practice. However, there was still a lack of EM master's and doctoral programs and research capacities need to be improved. More outstanding clinical and academic training should be provided to promote the rapid growth of EM in China.


Assuntos
Reanimação Cardiopulmonar , Medicina de Emergência , China , Escolaridade
6.
Pak J Med Sci ; 40(8): 1729-1734, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39281215

RESUMO

Objective: To evaluate the clinical effect of probiotics combined with Ulinastatin and Somatostatin in the treatment of severe acute pancreatitis. Methods: A retrospective study was conducted on 160 patients with severe acute pancreatitis treated in the First Affiliated Hospital of Bengbu Medical College from July 2021 to June 2023. There were 78 patients received Ulinastatin and Somatostatin treatment (Control group), and 82 patients received probiotics in addition to Ulinastatin and Somatostatin treatment (Observation group). The treatment effect and the time required to alleviate clinical symptoms were compared between the two groups. Serum levels of inflammatory factors, intestinal mucosal indexes and the incidence of adverse reactions before and after treatment were analyzed. Results: The total efficacy of the Observation group (95.12%) was higher than that of the Control group (85.90%) (P<0.05). Combined probiotic/Ulinastatin + Somatostatin treatment was associated with shorter time to remission of the clinical symptoms (P<0.05). After the treatment, serum levels of inflammatory factors in the two groups were decreased, and was significantly lower in the Observation group compared to the Control group (P<0.05). Similarly, post-treatment serum levels of intestinal mucosal indexes in the two groups were lower than before the treatment, and significantly lower in the Observation group (P<0.05). There was no significant difference in the incidence of adverse reactions between the groups (P>0.05). Conclusions: A combined regimen of probiotics, Ulinastatin and Somatostatin is safe and can more effectively relieve clinical symptoms in patients with severe acute pancreatitis, reduce levels of inflammatory factors, lower intestinal mucosal damage and improve the overall treatment effect compared to Ulinastatin and Somatostatin regimen alone.

7.
Microb Pathog ; 185: 106435, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37931825

RESUMO

Bacterial infections result in intestinal inflammation and injury, which affects gut health and nutrient absorption. Lipocalin 2 (Lcn2) is a protein that reacts to microbial invasion, inflammatory responses, and tissue damage. However, it remains unclear whether Lcn2 has a protective effect against bacterial induced intestinal inflammation. Therefore, this study endeavors to investigate the involvement of Lcn2 in the intestinal inflammation of mice infected with Enterohemorrhagic Escherichia coli O157:H7 (E. coli O157:H7). Lcn2 knockout (Lcn2-/-) mice were used to evaluate the changes of inflammatory responses. Lcn2 deficiency significantly exacerbated clinical symptoms of E. coli O157:H7 infection by reducing body weight and encouraging bacterial colonization of. Compared to infected wild type mice, infected Lcn2-/- mice had significantly elevated levels of pro-inflammatory cytokines in serum and ileum, including interleukin (IL)-6, IL-1ß, and tumor necrosis factor-α (TNF-α), as well as severe villi destruction in the jejunum. Furthermore, Lcn2 deficiency aggravated intestinal barrier degradation by significantly reducing the expression of tight junction proteins occludin and claudin 1, the content of myeloperoxidase (MPO) in the ileum, and the number of goblet cells in the colon. Our findings indicated that Lcn2 could alleviate inflammatory damage caused by E. coli O157:H7 infection in mice by enhancing intestinal barrier function.


Assuntos
Infecções por Escherichia coli , Escherichia coli O157 , Lipocalina-2 , Animais , Camundongos , Colo/metabolismo , Colo/microbiologia , Colo/patologia , Infecções por Escherichia coli/metabolismo , Infecções por Escherichia coli/patologia , Escherichia coli O157/genética , Escherichia coli O157/metabolismo , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Inflamação/metabolismo , Interleucina-6/metabolismo , Mucosa Intestinal/metabolismo , Mucosa Intestinal/microbiologia , Mucosa Intestinal/patologia , Lipocalina-2/genética , Lipocalina-2/metabolismo
8.
BMC Public Health ; 23(1): 821, 2023 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-37143051

RESUMO

BACKGROUND: The low birth rates and rapid population aging has drawn considerable attention from scholars and policymakers in China and around the world. In 2021, China launched the policy and supportive measures that allow up to 3 children per couple. This study aims to explore the influencing factors of the third-child fertility intention among women aged 20-34 years in China. METHODS: We draw data from the National Fertility Survey conducted in 2017. The nationally representative survey adopts a stratified, 3-stage, and probabilities proportional to size sampling method. A total of 61,588 valid samples aged 20-34 years old were obtained. Fertility desire and behavior, childbearing and service use, and potential influencing factors of fertility intention such as the history of pregnancy were assessed. RESULTS: In general, 5.01% of Chinese women of prime childbearing age had fertility intention for a third child, and the proportion varies by region across mainland China. Individual characteristics such as being ethnic minorities, being rural residents, and having more siblings are significantly positively correlated with the third-child fertility intention, while the intention was significantly lower among women with a higher income or education level, migrant women, and those engaged in the non-agricultural labor force. Women who already had a son had lower fertility intention for a third child. Moreover, it was the perceived acceptable costs of childcare services rather than the actual costs that mattered more for the fertility intention. CONCLUSIONS: Our study concludes a series of socioeconomic factors, and previous childbearing and childrearing experiences are crucial for women's fertility intention for a third child. These findings highlight the importance of launching supportive measures in addition to the introduction of the 3-child policy in promoting a fertility-friendly society.


Assuntos
Fertilidade , Intenção , Gravidez , Feminino , Humanos , Adulto Jovem , Adulto , Fatores Socioeconômicos , China , Coeficiente de Natalidade , Dinâmica Populacional , Países em Desenvolvimento
9.
BMC Public Health ; 22(1): 444, 2022 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-35247999

RESUMO

BACKGROUND: The prevalence of tooth loss varies across the globe among oldest-old individuals. The presence of fewer than 20 teeth in old age was associated with a decrease in people's health and quality of life. This paper explored the association between socioeconomics, health-related factors, and tooth loss among the population over the age of 80 in China. METHODS: The tooth loss status of older Chinese adults was collected with a structured questionnaire from the 8th wave of the Chinese Longitudinal Healthy Longevity Survey (CLHLS). A total of 6716 individuals aged 80 years and above were included. Logistic regression was used to assess the association between socioeconomic statuses, dietary intake at approximately 60 years old, health-related factors, and tooth loss. RESULTS: Of the 6716 individuals aged 80 years and above, the composition of the group with fewer teeth for both men and women was statistically significant in many ways. Multivariate logistic regression analyses show that for men, being older than 90 years and being ADL disabled (adjusted OR: 1.71, 95% CI: 1.01-2.89) are factors that are significantly and consistently associated with a higher risk of having fewer than 20 teeth, while having a higher household income per capita (adjusted OR: 0.56, 95% CI: 0.32-0.99) decreases the risk. For women, an age of above 95 years, brushing teeth less than once per day (adjusted OR: 1.96, 95% CI: 1.26-3.03), consuming sugar some of the time as opposed to less than once per month at approximately 60 years old (adjusted OR = 1.74, 95% CI: 1.15-2.62), and being ADL disabled (adjusted OR: 1.70, 95% CI: 1.04-2.77) are factors that are significantly associated with the risk of having fewer than 20 teeth. CONCLUSION: The analysis suggests that socioeconomic status, dietary intake in early old age, and ADL capacity are associated with the risk of having fewer teeth for the population aged 80 years and above, and the risk factors vary between sexes.


Assuntos
Perda de Dente , Adulto , Idoso , Idoso de 80 Anos ou mais , Pré-Escolar , China/epidemiologia , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Fatores de Risco , Fatores Socioeconômicos , Perda de Dente/epidemiologia
10.
BMC Neurol ; 21(1): 359, 2021 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-34530757

RESUMO

BACKGROUND: Reports have proven that shorter door-to-needle time (DTN time) indicates better outcomes in AIS patients received intravenous thrombolysis. Efforts have been made by hospitals and centers to minimize DTN time in many ways including introducing a stroke nurse. However, there are few studies to discuss the specific effect of stroke nurse on patients' prognosis. This study aimed to compare consecutive AIS patients before and after the intervention to analyze the effect of stroke nurse on clinical outcome of AIS patients. METHODS: In this retrospective study, we observed 1003 patients from November 2016 to December 2020 dividing in two groups, collected and analyzed AIS patients' medical history, clinical assessment information, important timelines, 90 mRS score, etc. Comparative analysis and mediation analysis were also used in this study. RESULTS: A total of 418 patients was included in this study, and 199 patients were enrolled in the stroke nurse group and 219 was in the preintervention group. Baseline characteristics of patients showed no significant difference except there seems more patients with previous ischemic stroke history in the group of stroke nurse. (p = 0.008). The median DTN time significantly decreased in the stroke nurse group (25 min versus 36 min, p < 0.001) and multivariate logistic regression analysis showed the 90-day mRS clinical outcome significantly improved in the stroke nurse group (p = 0.001). Mediation analysis indicated the reduction of DTN time plays a partial role on the 90 days mRS score and the stroke nurse has some direct effect on the improvement of clinical outcome (p = 0.006). CONCLUSIONS: The introduction of stroke nurse is beneficial to clinical outcome of AIS patients and can be use of reference in other hospitals or centers.


Assuntos
Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Isquemia Encefálica/complicações , Isquemia Encefálica/tratamento farmacológico , Fibrinolíticos/uso terapêutico , Humanos , Estudos Retrospectivos , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/tratamento farmacológico , Terapia Trombolítica , Tempo para o Tratamento , Ativador de Plasminogênio Tecidual/uso terapêutico , Resultado do Tratamento
11.
Environ Res ; 192: 110300, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33038368

RESUMO

Airborne particulate matter (PM) is a complex mixture containing various kinds of harmful components. Exposure to air PM is associated with childhood respiratory disease, but epidemiological data are limited concerning the circulating respiratory injury protein on the etiology of childhood respiratory disease. Specifically, the role of PM toxic components or its biological effective dose (adduct) in respiratory injury remains unclear. To demonstrate the dose-response relationship and the main mechanism on circulating club cell secretory protein (CC16) from PM compositions among children, we enrolled 273 boarding schoolchildren in China, including 110 and 163 children of whom were in the low- and high-PM exposed areas, respectively. In this study, we measured the internal exposure levels, including serum polycyclic aromatic hydrocarbons (PAH) adduct, urinary metals, and AhR expression, and detected the serum CC16 level as a lung injury marker. Environmental tobacco exposure in children was assessed by urinary cotinine. We found that significantly higher levels of serum CC16, benzo[a]pyridin-7,8-dihydroglycol-9,10-epoxide (BPDE)-albumin adduct, urinary molybdenum, selenium, arsenic, cadmium and barium, and lower level of AhR expression in high-PM exposed group. There was a good association between serum BPDE-albumin adduct and CC16 (ß = 0.222, P = 0.006). There was no association on urinary metals and serum CC16. BPDE-albumin adduct was directly associated with serum CC16 alternation [direct effect = 0.2044, 95% confidence interval (CI) = (0.0426, 0.36)]. PM could cause serum CC16 increased in children. PAH and its adduct might play a key role in lung injury during PM exposure.


Assuntos
Material Particulado , Hidrocarbonetos Policíclicos Aromáticos , Criança , China/epidemiologia , Exposição Ambiental , Humanos , Epidemiologia Molecular , Material Particulado/análise , Material Particulado/toxicidade , Hidrocarbonetos Policíclicos Aromáticos/análise , Hidrocarbonetos Policíclicos Aromáticos/toxicidade
12.
BMC Med Inform Decis Mak ; 21(1): 45, 2021 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-33557818

RESUMO

BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic has caused health concerns worldwide since December 2019. From the beginning of infection, patients will progress through different symptom stages, such as fever, dyspnea or even death. Identifying disease progression and predicting patient outcome at an early stage helps target treatment and resource allocation. However, there is no clear COVID-19 stage definition, and few studies have addressed characterizing COVID-19 progression, making the need for this study evident. METHODS: We proposed a temporal deep learning method, based on a time-aware long short-term memory (T-LSTM) neural network and used an online open dataset, including blood samples of 485 patients from Wuhan, China, to train the model. Our method can grasp the dynamic relations in irregularly sampled time series, which is ignored by existing works. Specifically, our method predicted the outcome of COVID-19 patients by considering both the biomarkers and the irregular time intervals. Then, we used the patient representations, extracted from T-LSTM units, to subtype the patient stages and describe the disease progression of COVID-19. RESULTS: Using our method, the accuracy of the outcome of prediction results was more than 90% at 12 days and 98, 95 and 93% at 3, 6, and 9 days, respectively. Most importantly, we found 4 stages of COVID-19 progression with different patient statuses and mortality risks. We ranked 40 biomarkers related to disease and gave the reference values of them for each stage. Top 5 is Lymph, LDH, hs-CRP, Indirect Bilirubin, Creatinine. Besides, we have found 3 complications - myocardial injury, liver function injury and renal function injury. Predicting which of the 4 stages the patient is currently in can help doctors better assess and cure the patient. CONCLUSIONS: To combat the COVID-19 epidemic, this paper aims to help clinicians better assess and treat infected patients, provide relevant researchers with potential disease progression patterns, and enable more effective use of medical resources. Our method predicted patient outcomes with high accuracy and identified a four-stage disease progression. We hope that the obtained results and patterns will aid in fighting the disease.


Assuntos
COVID-19 , Aprendizado Profundo , Progressão da Doença , COVID-19/diagnóstico , COVID-19/patologia , China , Previsões , Humanos , SARS-CoV-2
13.
Sensors (Basel) ; 21(2)2021 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-33419025

RESUMO

With the rapid development of the global navigation satellite system (GNSS), high-rate GNSS has been widely used for high-precision GNSS coseismic displacement retrieval. In recent decades, relative positioning (RP) and precise point positioning (PPP) are mainly adopted to retrieve coseismic displacements. However, RP can only obtain relative coseismic displacements with respect to a reference station, which might be subject to quaking during a large seismic event. While PPP needs a long (re)convergence period of tens of minutes. There is no convergence time needed in the variometric approach for displacements analysis standalone engine (VADASE) but the derived displacements are accompanied by a drift. Temporal point positioning (TPP) method adopts temporal-differenced ionosphere-free phase measurements between a reference epoch and the current epoch, and there is almost no drift in the displacement derived from TPP method. Nevertheless, the precise orbit and clock products should be applied in the TPP method. The studies in recent years are almost based on the postprocessing precise orbits and clocks or simulated real-time products. Since 2013, international GNSS service (IGS) has been providing an open-access real-time service (RTS), which consists of orbit, clock and other corrections. In this contribution, we evaluated the performance of real-time coseismic displacement retrieval based on TPP method with IGS RTS correction products. At first, the real-time precise orbit and clock offsets are derived from the RTS correction products. Then, the temporal-differenced ionosphere-free (IF) combinations are formed and adopted as the TPP measurements. By applying real-time precise orbit and clock offsets, the coseismic displacement can be real-timely retrieved based on TPP measurements. To evaluate the accuracy, two experiments including a stationary experiment and an application to an earthquake event were carried out. The former gives an accuracy of 1.8 cm in the horizontal direction and 4.1 cm in the vertical direction during the whole period of 15-min. The latter gives an accuracy of 1.2 cm and 2.4 cm in the horizontal and vertical components, respectively.

14.
Sensors (Basel) ; 21(1)2021 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-33406691

RESUMO

Global navigation satellite systems (GNSS) can attain centimeter level positioning accuracy, which is conventionally provided by real-time precise point positioning (PPP) and real-time kinematic (RTK) techniques. Corrections from the data center or the reference stations are required in these techniques to reduce various GNSS errors. The time-relative positioning approach differs from the traditional PPP and RTK in the sense that it does not require external real-time corrections. It computes the differences in positions of a single receiver at different epochs using phase observations. As the code observations are not used in this approach, its performance is not affected by the noise and multipath of code observations. High reliability is another advantage of time-relative precise positioning because the ambiguity resolution is not needed in this approach. Since the data link is not required in the method, this approach has been widely used in remote areas where wireless data link is not available. The main limitation of time-relative positioning is that its accuracy degrades over time between epochs because of the temporal variation of various errors. The application of the approach is usually limited to be within a time interval of less than 20 min. The purpose of this study was to increase the time interval of time-relative positioning and to extend the use of this method to applications with a longer time requirement, especially in remote areas without wireless communication. In this paper, the main error sources of the time-relative method are first analyzed in detail, and then the approach to improve the accumulated time relative positioning method is proposed. The performance of the proposed method is assessed using both static and dynamic observations with a duration as long as several hours. The experiments presented in this paper show that, among the four scenarios tested (i.e., GPS, GPS/Galileo, GPS/Galileo/BeiDou, and GPS/Galileo/BeiDou/GLONASS), GPS/Galileo/BeiDou performed best and GPS/Galileo/BeiDou/GLONASS performed worst. The maximum positioning errors were mostly within 0.5 m in the horizontal direction, even after three hours with GPS/Galileo/BeiDou. It is expected that the method could be used for positioning and navigation for as long as several hours with decimeter level horizontal accuracy in remote areas without wireless communication.

15.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 43(3): 406-413, 2021 Jun 30.
Artigo em Zh | MEDLINE | ID: mdl-34238417

RESUMO

Objective To evaluate the diagnostic performance of 1.5-T non-contrast free-breathing whole-heart magnetic resonance coronary angiography(MRCA)for≥50% and≥70% coronary artery stenosis in coronary artery disease(CAD).Methods Forty-one patients clinically scheduled for invasive coronary angiography(ICA)underwent 1.5-T non-contrast free-breathing whole-heart MRCA.The diagnostic performance for≥50% and≥70% stenosis was evaluated and compared using ICA as a reference standard.Results MRCA was completed in all the 41 patients with the total acquisition time of(10.1 ± 2.2)min.The sensitivity,specificity,and accuracy of MRCA for≥50% and≥70% stenosis were 100%(95% CI:89%-100%)and 82%(95%CI:63%-94%),38%(95%CI:9%-76%)and 54%(95%CI:25%-81%),and 88%(95%CI:73%-95%)and 73%(95%CI:57%-85%)on a per-patient basis,respectively;they were 95%(95%CI:87%-99%)and 86%(95%CI:73%-95%),58%(95%CI:45%-71%)and 76%(95%CI:65%-85%),and 78%(95%CI:69%-84%)and 80%(95%CI:71%-86%)on a per-vessel basis,respectively.The sensitivity of MRCA for≥50% stenosis was higher than that for≥70% stenosis(97%vs.88%,χ 2=5.73,P=0.017),and the specificity showed an opposite trend(86% vs. 94%,χ 2=14.12,P<0.001)on a per-segment basis.Conclusions The 1.5-T non-contrast whole-heart MRCA can detect both≥50% and≥70% coronary artery stenosis with high sensitivity and accuracy.MRCA showed lower sensitivity while higher specificity for≥70% stenosis than for≥50% stenosis on a per-segment basis.


Assuntos
Estenose Coronária , Angiografia Coronária , Estenose Coronária/diagnóstico por imagem , Humanos , Angiografia por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Valor Preditivo dos Testes , Sensibilidade e Especificidade
16.
Lipids Health Dis ; 19(1): 151, 2020 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-32586390

RESUMO

BACKGROUND: Coronary artery stenosis induces heart diseases including acute coronary syndrome (ACS). Some studies reported the ceramide species are associated with the ACS and major adverse cardia and cerebrovascular events (MACE). However, few studies investigated the association between plasma ceramide levels and the severity of stenosis, together with the onset of diseases. This aim of the present study was to investigate the association betweencertain ceramide species, coronary artery stenosis and acute coronary syndrome. METHODS: Five hundred fifty-three patients with definite or suspected CAD were recruited and received angiography. Subjects were assigned into 4 groups according to the severity of coronary artery stenosis. The measurements of 4 plasma ceramide species, namely, Cer (d18:1/16:0), Cer (d18:1/18:0), Cer (d18:1/24:1), Cer (d18:1/24:0) were carried out by Liquid chromatography-tandem mass spectrometry (LC-MS/MS) and the ratio of Cer (d18:1/16:0), Cer (d18:1/18:0) and Cer (d18:1/24:1) to Cer (18:1/24:0), respectively, were calculated as index to evaluate the association between plasma ceramides levels and coronary artery stenosis. Multiple logistic regression analysis was used to establish the prognostic model for the prediction of ACS risk. RESULTS: After the adjustment by multiple clinical risk factors including age, gender, pre-existing myocardial/cerebral infarction, hemoglobin A1c% (HbA1c%), smoking and the diagnosis during index hospitalization, multiple logistic regression analysis showed that the high ratio of Cer (d18:1/24:1) to Cer (d18:1/24:0), female gender, HbA1c%, unstable angina (UAP) and acute myocardial infarction (AMI) diagnosis (compared with atherosclerosis) during index hospitalization were associated with more severe coronary artery stenosis. Furthermore, the prognostic model was established after adjustment of risk factors and the area under curve (AUC) of receiver operating characteristics (ROC) for the prognostic model was 0.732 and 95% CI was 0.642-0.822. CONCLUSION: The severity of coronary artery stenosis is associated with high ratio of Cer (d18:1/24:1) to Cer (d18:1/24:0), female gender, HbA1c% and AMI. Although the reported prognostic model showed a good discrimination, further investigation on long term MACE is needed to evaluate the role of ceramide for the prediction of MACE risk.


Assuntos
Ceramidas/sangue , Doença da Artéria Coronariana/sangue , Estenose Coronária/sangue , Idoso , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , Angiografia Coronária , Doença da Artéria Coronariana/diagnóstico por imagem , Estenose Coronária/diagnóstico por imagem , Feminino , Hemoglobinas Glicadas/análise , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/epidemiologia , Infarto do Miocárdio/etiologia , Prognóstico , Curva ROC , Fatores de Risco
17.
BMC Public Health ; 20(1): 968, 2020 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-32560710

RESUMO

BACKGROUND: Although some studies have reported the association between life negative events and depressive disorders, very limited studies have examined the association between life negative events exposure and depressive symptoms risk among Chinese older adults. METHODS: Data were obtained from the China Longitudinal Ageing Social Survey (CLASS), which was a stratified, multi-stage, probabilistic sampling survey, conducted in 2014. General linear regression and logistic regression were used to examine the association between life negative events exposure and depressive symptoms among Chinese older adults. RESULTS: Life negative events showed statistical dose-response association with depressive symptoms risk after adjustment for the confounding factors (Ptrend < 0.001). Under consideration of life negative events exposure, participants who lived in rural areas, without a spouse or live alone were vulnerable to depressive symptoms. CONCLUSIONS: Life negative events played a risk role of depressive symptoms among Chinese older adults, especially among those in rural areas, females or without a spouse. Our current study is valuable for the development of special prevention depressive symptoms programs among elderly individuals, especially those who have experienced negative events.


Assuntos
Envelhecimento/psicologia , Povo Asiático/psicologia , Depressão/epidemiologia , Acontecimentos que Mudam a Vida , Idoso , Idoso de 80 Anos ou mais , China/epidemiologia , Estudos Transversais , Depressão/psicologia , Feminino , Humanos , Modelos Logísticos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários
18.
Sensors (Basel) ; 20(21)2020 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-33114036

RESUMO

An accurate observation model and statistical model are critical in underwater integrated navigation. However, it is often the case that the statistical characteristics of noise are unknown through the ultra-short baseline (USBL) system/Doppler velocity log (DVL) integrated navigation in the deep-sea. Additionally, the velocity of underwater vehicles relative to the bottom of the sea or the currents is commonly provided by the DVL, and an adaptive filtering solution is needed to correctly estimate the velocity with unknown currents. This paper focuses on the estimation of unknown currents and measurement noise covariance for an underwater vehicle based on the USBL, DVL, and a pressure gauge (PG), and proposes a novel unbiased adaptive two-stage information filter (ATSIF) for the underwater vehicle (UV) with an unknown time-varying currents velocity. In the proposed algorithm, the adaptive filter is decomposed into a standard information filter and an unknown currents velocity information filter with interconnections, and the time-varying unknown ocean currents and measurement noise covariance are estimated. The simulation and experimental results illustrate that the proposed algorithm can make full use of high-precision observation information and has better robustness and navigation accuracy to deal with time-varying currents and measurement outliers than existing state-of-the-art algorithms.

19.
Sensors (Basel) ; 20(20)2020 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-33050510

RESUMO

Recently, some smartphone manufacturers have subsequently released dual-frequency GNSS smartphones. With dual-frequency observations, the positioning performance is expected to be significantly improved. Cycle-slip detection and correction play an important role in high-precision GNSS positioning, such as precise point positioning (PPP) and real-time kinematic (RTK) positioning. The TurboEdit method utilizes Melbourne-Wübbena (MW) and phase ionospheric residual (PIR) combinations to detect cycle-slips, and it is widely used in the data processing applications for geodetic GNSS receivers. The smartphone pseudorange observations are proved to be much noisier than those collected with geodetic GNSS receivers. Due to the poor pseudorange observation, the MW combination would be difficult to detect small cycle-slips. In addition, some specific cycle-slip combinations, where the ratio of cycle-slip values at different carrier frequencies is close to the frequency ratio, are also difficult to be detected by PIR combination. As a consequence, the traditional TurboEdit method may fail to detect specific small cycle-slip combinations. In this contribution, we develop a modified TurboEdit cycle-slip detection and correction method for dual-frequency smartphone GNSS observations. At first, MW and PIR combinations are adopted to detect cycle-slips by comparing these two combinations with moving-window average values. Then, the epoch-differenced wide-lane combinations are used to estimate the changes of smartphone position and clock bias, and the cycle-slip is identified by checking the largest normalized residual whether it exceeds a predefined threshold value. The process of estimation and cycle-slip identification is implemented in an iterative way until there is no over-limit residual or there is no redundant measurement. At last, the cycle-slip values at each frequency are estimated with the epoch-differenced wide-lane and ionosphere-free combinations, and the least-square ambiguity decorrelation adjustment (LAMBDA) method is adopted to further obtain an integer solution. The proposed method has been verified with 1 Hz dual-frequency smartphone GNSS data. The results show that the modified TurboEdit method can effectively detect and correct even for specific small cycle-slip combinations, e.g., (4, 3), which is difficult to be detected with the traditional TurboEdit method.

20.
Molecules ; 25(7)2020 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-32218351

RESUMO

Lactoferrin (Lf) is a conserved iron-binding glycoprotein with antimicrobial activity, which is present in secretions that recover mucosal sites regarded as portals of invaded pathogens. Although numerous studies have focused on exogenous Lf, little is known about its expression of endogenous Lf upon bacterial infection. In this study, we investigated the distribution of Lf in mice intestine during Escherichia coli (E. coli) K88 infection. PCR and immunohistology staining showed that mRNA levels of Lf significantly increased in duodenum, ileum and colon, but extremely decreased in jejunum at 8 h and 24 h after infection. Meanwhile, endogenous Lf was mostly located in the lamina propria of intestine villi, while Lf receptor (LfR) was in the crypts. It suggested that endogenous Lf-LfR interaction might not be implicated in the antibacterial process. In addition, it was interesting to find that the infiltration of neutrophils into intestine tissues was changed similarly to Lf expression. It indicated that the variations of Lf expression were rather due to an equilibrium between the recruitment of neutrophils and degranulation of activated neutrophils. Thus, this new knowledge will pave the way to a more effective understanding of the role of Lf in intestinal mucosal immunity.


Assuntos
Infecções Bacterianas/metabolismo , Intestinos/microbiologia , Intestinos/patologia , Lactoferrina/metabolismo , Neutrófilos/metabolismo , Animais , Infecções Bacterianas/complicações , Infecções Bacterianas/microbiologia , Modelos Animais de Doenças , Escherichia coli/fisiologia , Inflamação/complicações , Inflamação/patologia , Masculino , Camundongos Endogâmicos C57BL
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