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1.
Sensors (Basel) ; 23(1)2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36617045

RESUMO

The merging of environmental maps constructed by individual UAVs alone and the sharing of information are key to improving the efficiency of distributed multi-UAVexploration. This paper investigates the raster map-merging problem in the absence of a common reference coordinate system and the relative position information of UAVs, and proposes a raster map-merging method with a directed crossover multidimensional perturbation variational genetic algorithm (DCPGA). The algorithm uses an optimization function reflecting the degree of dissimilarity between the overlapping regions of two raster maps as the fitness function, with each possible rotation translation transformation corresponding to a chromosome, and the binary encoding of the coordinates as the gene string. The experimental results show that the algorithm could converge quickly and had a strong global search capability to search for the optimal overlap area of the two raster maps, thus achieving map merging.


Assuntos
Algoritmos
2.
Materials (Basel) ; 14(18)2021 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-34576644

RESUMO

In view of the problems of traditional repair materials for anchorage concrete of expansion joints, such as ease of damage and long maintenance cycles, the design of polyurethane concrete was optimized in this article, which could be used for rapid repair of concrete in anchorage zone of expansion joints. A new type of carbon fiber grid-polyurethane concrete system was designed, which makes the carbon fiber grid have an excellent synergistic effect with the quick-hardening and high-strength polyurethane concrete, and improved the flexural bearing capacity of the polyurethane concrete. Through the four-point bending test, the influence of the parameters such as the number of grid layers, grid width, and grid density on the flexural bearing capacity of polyurethane concrete beams was tested. The optimum preparation process parameters of carbon fiber grid were obtained to improve the flexural performance of polyurethane concrete. Compared with the Normal specimen, C-80-1's average flexural strength increased by 47.7%, the failure strain along the beam height increased by 431.1%, and the failure strain at the bottom of the beam increased by 68.9%. The best width of the carbon fiber grid was 80 mm, and the best number of reinforcement layers was one layer. The test results show that the carbon fiber grid could improve the flexural bearing capacity of polyurethane concrete. The carbon fiber grid-polyurethane concrete system provides a new idea for rapid repair of the anchorage zone of bridge expansion joints, and solves the problems such as ease of damage and long maintenance cycles of traditional repair materials, which can be widely used in the future.

3.
Materials (Basel) ; 14(14)2021 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-34300759

RESUMO

In order to solve issues related to bridge girders, expansion devices and road surfaces, as well as other structures that are prone to fatigue failure, a kind of fatigue-resistant elastic polyurethane concrete (EPUC) was obtained by adding waste rubber particles (40 mesh with 10% fine aggregate volume replacement rate) to conventional engineering polyurethane concrete (PUC). Based on the preparation and properties of EPUC, its constitutive relation was proposed through compression and tensile tests; then, a scanning electron microscope (SEM), an atomic force microscope (AFM) and a 3D non-contact surface profilometer were used to study the failure morphology and micromechanisms of EPUC. On this basis, four-point bending fatigue tests of EPUC were carried out at different temperature levels (-20 °C, 0 °C, 20 °C) and different strain levels (400 µÎµ~1200 µÎµ). These were used to analyze the stiffness modulus, hysteresis angle and dissipated energy of EPUC, and our results outline the fatigue life prediction models of EPUC at different temperatures. The results show that the addition of rubber particles fills the interior of EPUC with tiny elastic structures and effectively optimizes the interface bonding between aggregate and polyurethane. In addition, EPUC has good mechanical properties and excellent fatigue resistance; the fatigue life of EPUC at a room temperature of 600 µÎµ can grow by more than two million times, and it also has a longer service life and reduced disease frequency, as well as fewer maintenance requirements. This paper will provide a theoretical and design basis for the fatigue resistance design and engineering application of building materials. Meanwhile, the new EPUC material has broad application potential in terms of roads, bridges and green buildings.

4.
BMC Cancer ; 17(1): 881, 2017 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-29268706

RESUMO

BACKGROUND: Because glycosylation is one of the most common post-translational modifications of proteins and because changes in glycosylation have been shown to have a significant correlation with the development of many cancer types, we investigated the serum N-glycome used to diagnose, stage and evaluate the pathological outcomes in IgD multiple myeloma. METHODS: Serum samples were available for 20 patients with IgD multiple myeloma, 41 patients with light chain multiple myeloma and 42 healthy control subjects. Serum N-glycans were released and analysed using DNA sequencer-assisted fluorophore-assisted capillary electrophoresis. RESULTS: Characteristic changes were revealed in the serum N-glycome of IgD myeloma. In particular, three N-glycans (NG1(6)A2F, Peak3; NG1(3)A2F, Peak4; NA2FB, Peak7) showed increased clinical value. The best area under the ROC curve of NG1(6)A2F to diagnose IgD myeloma was 0.981, with a 95.0% sensitivity and 95.2% specificity, and that of NG1(3)A2F was 0.936, with a 95.0% sensitivity and 78.6% specificity. The best area under the ROC curve of NA2FB/NG1(3)A2F to differentially diagnose IgD myeloma versus light chain myeloma was 0.744, with a 95.3% sensitivity and 50.0% specificity. The level of NG1(3)A2F was correlated with the international staging system, while the higher abundance of NA2FB presented in IgD myeloma was predictive of a shorter progression-free survival. CONCLUSIONS: The advent of serum N-glycan signatures may play a role in the diagnosis, staging and prognosis of IgD myeloma and will serve as the foundation for a precision medicine approach to this rare subtype of multiple myeloma.


Assuntos
Biomarcadores Tumorais/sangue , Proteínas Sanguíneas/análise , Imunoglobulina D/sangue , Mieloma Múltiplo/diagnóstico , Polissacarídeos/sangue , Polissacarídeos/química , Estudos de Casos e Controles , Feminino , Seguimentos , Glicosilação , Humanos , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/sangue , Prognóstico , Processamento de Proteína Pós-Traducional , Taxa de Sobrevida
5.
PLoS One ; 10(6): e0127022, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26075387

RESUMO

The aim of this study was to evaluate the diagnostic and differential diagnostic power of serum N-glycans for light chain multiple myeloma (LCMM). A total of 167 cases of subjects, including 42 LCMM, 42 IgG myeloma, 41 IgA myeloma, and 42 healthy controls were recruited in this study. DNA sequencer-assisted fluorophore-assisted capillary electrophoresis (DSA-FACE) was applied to determine the quantitive abundance of serum N-glycans. The core fucosylated, bisecting and sialylated modifications were analyzed in serum of LCMM patients (n=20) and healthy controls (n=20) randomly selected from the same cohort by lectin blot. Moreover, serum sialic acid (SA) level was measured by enzymatic method. We found two N-glycan structures (NG1A2F, Peak3; NA2FB, Peak7) showed the optimum diagnostic efficacy with area under the ROC curve (AUC) 0.939 and 0.940 between LCMM and healthy control. The sensitivity and specificity of Peak3 were 88.1% and 92.9%, while Peak7 were 92.9% and 97.6%, respectively. The abundance of Peak3 could differentiate LCMM from IgG myeloma with AUC 0.899, sensitivity 100% and specificity 76.2%, and Peak7 could be used to differentiate LCMM from IgA myeloma with AUC 0.922, sensitivity 92.9% and specificity 82.9%. Serum SA level was significantly higher in patients with LCMM than that in healthy controls. Moreover, the decreased core fucosylation, bisecting and increased sialylation characters of serum glycoproteins were observed in patients with LCMM. We concluded that serum N-glycan could provide a simple, reliable and non-invasive biomarker for LCMM diagnosis and abnormal glycosylation might imply a new potential therapeutic target in LCMM.


Assuntos
Biomarcadores Tumorais/sangue , Cadeias Leves de Imunoglobulina/sangue , Mieloma Múltiplo/sangue , Mieloma Múltiplo/diagnóstico , Polissacarídeos/sangue , Estudos de Casos e Controles , Diagnóstico Diferencial , Glicoproteínas/sangue , Glicosilação , Humanos , Ácido N-Acetilneuramínico/sangue , Sensibilidade e Especificidade , Índice de Gravidade de Doença
6.
BMC Health Serv Res ; 14: 390, 2014 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-25218509

RESUMO

BACKGROUND: Although China experienced great improvement in their health system, disputes between patients and doctors have increasingly intensified, reaching an unprecedented level. Retrospective analysis of medical malpractice litigation can discover the characteristics and fundamental cause of these disagreements. METHODS: We analyzed medical malpractice litigation data from 1998 to 2011 for characteristics of claims via a litigation database within a nationwide database of cases (1086 cases) in China, including claims, liabilities, injures, and compensation payments. RESULTS: Among the cases analyzed, 76 percent of claims received compensation in civil judgment (640 out of 841), while 93 percent were fault liability in paid judgment (597 out of 640). The average time span between the occurrence of the injury dispute and closure of claims was 3 years. Twenty-two percent of claims (183 of 841) were caused by injury, poisoning, and other external causes. Seventy-nine percent of claims (472 of 597) were contributed to by errors in medical technology. The median damage compensation payment for death was significantly lower than for serious injuries (P < 0.001; death, $13270 [IQR, $7617-$23181]; serious injury, $23721 [IQR, $10367-$57058]). Finally, there was no statistically significant difference in the median mental compensation between minor injury, serious injury, and death (P = 0.836). CONCLUSION: The social reasons for the conflict and high payment were catastrophic out-of-pocket health-care expense in addition to the high expectations for treatment in China. There were no distinguishing features between China and other countries with respect to time of suits, facilities, and specialties in these claims. The compensation for damages in different medical injuries was unfair in China.


Assuntos
Compensação e Reparação/legislação & jurisprudência , Imperícia/economia , Imperícia/legislação & jurisprudência , Erros Médicos/economia , Erros Médicos/legislação & jurisprudência , China , Humanos , Responsabilidade Legal
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