Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 77
Filtrar
Más filtros

Banco de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
Ann Hematol ; 103(1): 153-162, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37749319

RESUMEN

The purpose is to ascertain the clinical impact of Castleman disease (CD) by reassessment of the real-world data from Peking University First Hospital (PKUFH). The results will contribute to the standardization of diagnosis and treatment on CDs. Based on the last 15-year retrospective real-world data from Peking University First Hospital (PKUFH), we reclassified and re-evaluated the clinical and pathological information of patients with pathologically suspected diagnosis of CD. A total of 203 patients were included in our study, in which the diagnosis of CD was confirmed in 189 cases, including 118 patients with unicentric CD (UCD, n = 118, 62.4%) and 71 patients with multicentric CD (MCD, n = 71, 37.6%). A total of 44.1% (n = 52) of UCDs in our cohort were complicated with paraneoplastic pemphigus (PNP). The treatment of UCD is primarily surgical, with a 5-year overall survival (OS) of 88.1%. Patients with PNP had a poorer prognosis than those without PNP (82.9% (95% CI 123-178) vs 92.8% (95% CI 168-196), log-rank p = 0.041). The rate of concurrent systemic symptoms was 74.6% (n = 53), and renal involvement occurred in 49.3% (n = 35) MCD patients. The MCD treatments were mainly chemotherapy regimens, with a 5-year OS of 77.6% (95% CI, 143-213). Patients with UCD demonstrate a better overall prognosis than patients with MCD. But the prognosis of those complicated with PNP was poor. The differential diagnosis of MCD is extensive. MCD treatment in China is heterogeneous. The inaccessibility of anti-IL-6-targeted drugs in China may contribute to the poor prognosis for patients with MCD.A preprint has previously been published (Guo et al. 34).


Asunto(s)
Enfermedad de Castleman , Humanos , Enfermedad de Castleman/diagnóstico , Enfermedad de Castleman/epidemiología , Enfermedad de Castleman/terapia , Estudios Retrospectivos , Beijing/epidemiología , Pronóstico , China/epidemiología
2.
Environ Sci Technol ; 58(9): 4291-4301, 2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38385161

RESUMEN

Photochemical ozone (O3) formation in the atmospheric boundary layer occurs at both the surface and elevated altitudes. Therefore, the O3 formation sensitivity is needed to be evaluated at different altitudes before formulating an effective O3 pollution prevention and control strategy. Herein, we explore the vertical evolution of O3 formation sensitivity via synchronous observations of the vertical profiles of O3 and proxies for its precursors, formaldehyde (HCHO) and nitrogen dioxide (NO2), using multi-axis differential optical absorption spectroscopy (MAX-DOAS) in urban areas of the Beijing-Tianjin-Hebei (BTH), Yangtze River Delta (YRD), and Pearl River Delta (PRD) regions in China. The sensitivity thresholds indicated by the HCHO/NO2 ratio (FNR) varied with altitude. The VOC-limited regime dominated at the ground level, whereas the contribution of the NOx-limited regime increased with altitude, particularly on heavily polluted days. The NOx-limited and transition regimes played more important roles throughout the entire boundary layer than at the surface. The feasibility of extreme NOx reduction to mitigate the extent of the O3 pollution was evaluated using the FNR-O3 curve. Based on the surface sensitivity, the critical NOx reduction percentage for the transition from a VOC-limited to a NOx-limited regime is 45-72%, which will decrease to 27-61% when vertical evolution is considered. With the combined effects of clean air action and carbon neutrality, O3 pollution in the YRD and PRD regions will transition to the NOx-limited regime before 2030 and be mitigated with further NOx reduction.


Asunto(s)
Contaminantes Atmosféricos , Ozono , Compuestos Orgánicos Volátiles , Ozono/análisis , Contaminantes Atmosféricos/análisis , Dióxido de Nitrógeno/análisis , Compuestos Orgánicos Volátiles/análisis , Monitoreo del Ambiente/métodos , China
3.
Small ; 19(9): e2206258, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36538746

RESUMEN

In view of high-performance, multifunctional, and low-carbon development of infrastructures, there is a growing demand for smart engineering materials, making infrastructures intelligent. This paper reports a new-generation self-sensing cementitious composite (SSCC) incorporated with a hierarchically structured carbon fiber (CF)-carbon nanotube (CNT) composite filler (CF-CNT), which is in situ synthesized by directly growing CNT on CF. Various important factors including catalyst, temperature, and gas composition are considered to investigate their kinetic and thermodynamic influence on CF-CNT synthesis. The reciprocal architecture of CF-CNT not only alleviates the CNT aggregation, but also significantly improves the interfacial bonding between CF-CNT and matrix. Due to the synergic and spatially morphological effects of CF-CNT, that is, the formation of widely distributed multiscale reinforcement networks, SSCCs with CF-CNTs exhibit high mechanical properties and electrical conductivity as well as excellent self-sensing performances, particularly enhanced sensing repeatability. Moreover, the SSCCs with CF-CNTs are integrated into a full-scale maglev girder to devise a smart system for crack development monitoring. The system demonstrates high sensitivity and fidelity to capture the initiation of cracks/damage, as well as progressive and sudden damage events until the complete failure of the maglev girder, indicating its considerable potential for structural health monitoring of infrastructures.

4.
Ann Hematol ; 102(4): 961-966, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36864209

RESUMEN

Patients with hematological malignancies who experience severe infections are at risk of developing dangerous complications due to excessive inflammatory cytokines. To improve the prognosis, it is crucial to identify better ways to manage the systemic inflammatory storm after infection. In this study, we evaluated four patients with hematological malignancies who developed severe bloodstream infections during the agranulocytosis phase. Despite receiving antibiotics, all four patients presented elevated serum IL-6 levels as well as persistent hypotension or organ injury. Adjuvant therapy with tocilizumab, an IL-6-receptor antibody, was administered, and three of the four patients showed significant improvement. Unfortunately, the fourth patient died due to multiple organ failure caused by antibiotic resistance. Our preliminary experience suggests that tocilizumab, as an adjuvant therapy, may help alleviate systemic inflammation and reduce risk of organ injury in patients with elevated IL-6 levels and severe infection. Further randomized controlled trials are needed to confirm the effectiveness of this IL-6 targeting approach.


Asunto(s)
COVID-19 , Neoplasias Hematológicas , Humanos , Interleucina-6 , SARS-CoV-2 , Síndrome de Liberación de Citoquinas , Resultado del Tratamiento , Neoplasias Hematológicas/complicaciones , Neoplasias Hematológicas/tratamiento farmacológico
5.
Sensors (Basel) ; 23(11)2023 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-37299988

RESUMEN

Carbon-fiber-reinforced polymer (CFRP) is a type of composite material with many superior performances, such as high tensile strength, light weight, corrosion resistance, good fatigue, and creep performance. As a result, CFRP cables have great potential to replace steel cables in prestressed concrete structures. However, the technology to monitor the stress state in real-time throughout the entire life cycle is very important in the application of CFRP cables. Therefore, an optical-electrical co-sensing CFRP cable (OECSCFRP cable) was designed and manufactured in this paper. Firstly, a brief description is outlined for the production technology of the CFRP-DOFS bar, CFRP-CCFPI bar, and CFRP cable anchorage technology. Subsequently, the sensing and mechanical properties of the OECS-CFRP cable were characterized by serious experiments. Finally, the OECS-CFRP cable was used for the prestress monitoring of an unbonded prestressed RC beam to verify the feasibility of the actual structure. The results show that the main static performance indexes of DOFS and CCFPI meet the requirements of civil engineering. In the loading test of the prestressed beam, the OECS-CFRP cable can effectively monitor the cable force and the midspan defection of the beam so as to obtain the stiffness degradation of the prestressed beam under different loads.


Asunto(s)
Polímeros de Estímulo Receptivo , Fibra de Carbono , Polímeros , Comercio
6.
Int J Med Sci ; 19(2): 225-232, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35165508

RESUMEN

Background: 5-Hydroxymethylcytosine (5-hmC), a stable epigenetic marker, is closely related to tumor staging, recurrence and survival, but the prognostic value of 5-hmC in primary testicular diffuse large B-cell lymphoma (PT-DLBCL) remains unclear. This study aimed to investigate the 5-hmC expression in PT-DLBCL and evaluate its prognostic value. Methods: A total of 34 patients with PT-DLBCL treated in the Department of Hematology from August 2000 to August 2020 were included in this study. The expression of 5-hmC in PT-DLBCL tissues and normal testicular tissues were assessed by immunohistochemistry. 5-hmC staining is estimated as a percentage under every nuclear staining intensity score (0-3), 0 or 1 of which were regarded as 5-hmC reduction. The quantification of 5-hmC reduction is defined as the percentage of cells with 5-hmC staining scores of 0 and 1. According 5-hmC reduction of 80%, a 5-hmC reduction of <80% is regarded as "5-hmC high-level group", and a 5-hmC reduction of ≥80% is regarded as "5-hmC low-level group". Furthermore, Cox regression model was used to evaluate the prognostic value of all covariates. Results: The median percentage of 5-hmC reduction in the PT-DLBCL group was 77.50% (60%-90%), the median 5-hmC reduction in the normal testicular tissues was 30% (20%-50%). Compared with normal testicular tissue, 5-hmC levels in PT-DLBCL tissue were significantly decreased (p<0.05). Of the 34 PT-DLBCL patients, 17 had tumors with relatively low 5-hmC expression (5-hmC reduction of ≥80%) and 17 had tumors with relatively high 5-hmC expression (5-hmC reduction of < 80%). 5-hmC expression was negatively correlated with international prognostic index (p = 0.037), while there was no significant difference in 5-hmC decrease among different groups of age at diagnosis, lactate dehydrogenase, testicular lymphoma involvement (unilateral or bilateral), Ki-67 and tumor diameter. Relatively low 5-hmC expression indicated shorter overall survival (OS) (5-year OS 50.2% vs 81.3%, p=0.022) and progression-free survival (PFS) (5-year PFS 38.5% vs 70.7%, p=0.001). Cox multivariate analysis of IPI (2-3 vs. 0-1), intrathecal prophylaxis (No vs. Yes), and 5-hmC reduction (≥80% vs. <80%) showed that 5-hmC reduction ≥80% (hazard ratio: 7.252, p = 0.005) and not receiving intrathecal prophylaxis (hazard ratio: 7.207, p =0.001) are independent risk factors for poor prognosis of PT-DLBCL. Conclusion: Our results suggested that 5-hmC decline can be identified as a poor prognostic predictor for PT-DLBCL. It is necessary to further explore the underlying mechanism of this epigenetic marker to identify methods to re-establish 5-hmC levels and provide new targets for cancer therapy.


Asunto(s)
5-Metilcitosina/análogos & derivados , Linfoma de Células B Grandes Difuso/diagnóstico , Estadificación de Neoplasias/métodos , Neoplasias Testiculares/diagnóstico , 5-Metilcitosina/análisis , Anciano , Biomarcadores de Tumor/genética , Humanos , Inmunohistoquímica , Linfoma de Células B Grandes Difuso/genética , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Pronóstico , Modelos de Riesgos Proporcionales , Neoplasias Testiculares/genética , Testículo/metabolismo
7.
Environ Geochem Health ; 44(3): 979-991, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34131853

RESUMEN

The enrichment of heavy metals in air-borne particulate matters poses a great threat to health. In order to understand the mineralogical characteristics and sources of heavy metals in atmospheric particulate matter in coal mining cities, PM2.5 (particulate matter with an aerodynamic diameter less than 2.5 µm), PM10 (particulate matter with an aerodynamic diameter less than 10 µm) and TSP (total suspended particulates) were sampled from Huainan city, China in December 2016 and May 2017. The contents of heavy metals in TSP are the highest, while those in PM2.5 are the lowest. Zn, Mn, and Pb are the main components of heavy metals in Huainan atmospheric particulates. Straw burning activities may result in relatively higher atmospheric particulate matter content in summer than that in winter. The proportion of mineral particles in the studied particulate matters was the highest (40.79%), followed by soot aggregates (35.55%) and coal fly ash (19.74%). The results of energy spectrum analysis show that the main component of soot aggregates is C, and other contents are contributed by elements such as O and Si. Coal fly ash mainly contains C, O, Si, and a small amount of Al and Na. As, Cd, and Hg are the most easily enriched heavy metals. Industrial emissions, traffic discharges, coal combustion and dust emissions were found to be the main sources of heavy metals in atmospheric particulates.


Asunto(s)
Contaminantes Atmosféricos , Metales Pesados , Contaminantes Atmosféricos/análisis , China , Ciudades , Monitoreo del Ambiente , Metales Pesados/análisis , Material Particulado/análisis , Estaciones del Año
8.
J Environ Sci (China) ; 122: 92-104, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35717094

RESUMEN

Formaldehyde (HCHO) and glyoxal (CHOCHO) are important oxidization intermediates of most volatile organic compounds (VOCs), but their vertical evolution in urban areas is not well understood. Vertical profiles of HCHO, CHOCHO, and nitrogen dioxide (NO2) were retrieved from ground-based Multi-Axis Differential Optical Absorption Spectroscopy (MAX-DOAS) observations in Hefei, China. HCHO and CHOCHO vertical profiles prefer to occur at higher altitudes compared to NO2, which might be caused by the photochemistry-oxidation of longer-lived VOCs at higher altitudes. Monthly means of HCHO concentrations were higher in summer, while enhanced amounts of NO2 were mainly observed in winter. CHOCHO exhibited a hump-like seasonal variation, with higher monthly-averaged values not only occurred in warm months (July-August) but also in cold months (November-December). Peak values mainly occurred during noon for HCHO but emerged in the morning for CHOCHO and NO2, suggesting that HCHO is stronger link to photochemistry than CHOCHO. We further use the glyoxal to formaldehyde ratio (GFR) to investigate the VOC sources at different altitudes. The lowest GFR value is almost found in the altitude from 0.2 to 0.4 km, and then rises rapidly as the altitude increases. The GFR results indicate that the largest contributor of the precursor VOC is biogenic VOCs at lower altitudes, while at higher altitudes is anthropogenic VOCs. Our findings provide a lot more insight into VOC sources at vertical direction, but more verification is recommended to be done in the future.


Asunto(s)
Contaminantes Atmosféricos , Compuestos Orgánicos Volátiles , Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente/métodos , Formaldehído/análisis , Glioxal/análisis , Dióxido de Nitrógeno/análisis , Análisis Espectral , Compuestos Orgánicos Volátiles/análisis
9.
J Environ Sci (China) ; 111: 75-83, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34949375

RESUMEN

New particle formation (NPF) events are an increasingly interesting topic in air quality and climate science. In this study, the particle number size distributions, and the frequency of NPF events over Hefei were investigated from November 2018 to February 2019. The proportions of the nucleation mode, Aitken mode, and accumulation mode were 24.59%, 53.10%, and 22.30%, respectively, which indicates the presence of abundant ultrafine particles in Hefei. Forty-six NPF events occurred during the observation days, accounting for 41.82% of the entire observation period. Moreover, the favorable meteorological conditions, potential precursor gases, and PM2.5 range of the NPF events were analyzed. Compared to non-NPF days, the NPF events preferentially occurred on days with lower relative humidity, higher wind speeds, and higher temperatures. When the PM2.5 was 15-20, 70-80, and 105-115 µg/m3, the frequency of the NPF events was higher. Nucleation mode particles were positively related to atmospheric oxidation indicated by ozone when PM2.5 ranged from 15 to 20 µg/m3, and related to gaseous precursors like SO2 and NO2 when PM2.5 was located at 70-80 and 105-115 µg/m3. On pollution days, NPF events did not directly contribute to the increase in the PM2.5 in the daytime, however, NPF events would occur during the night and the growth of particulate matter contributes to the nighttime PM2.5 contents. This could lead to pollution that lasted into the next day. These findings are significant to the improvement of our understanding of the effects of aerosols on air quality.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Ozono , Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis , China , Monitoreo del Ambiente , Tamaño de la Partícula , Material Particulado/análisis , Ríos , Estaciones del Año
10.
World J Surg Oncol ; 19(1): 24, 2021 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-33482806

RESUMEN

BACKGROUND: Multiple myeloma causes different types of renal injury. C3 glomerulonephritis (C3GN) is characterised by an abnormal deposition of complement C3 in the glomeruli due to abnormal activation of the alternative pathway of the complement system. While the association between C3GN and multiple myeloma has been well established, mild renal injury by C3GN in multiple myeloma patients with high levels of light chain has not been reported. CASE PRESENTATION: A 55-year-old Chinese man presented with proteinuria. Combined with immunofixation electrophoresis, bone marrow biopsy, and renal biopsy, he was diagnosed with IgA-type multiple myeloma accompanied by C3GN and light chain proximal tubulopathy without crystal deposits. Although he had a higher level of lambda serum-free light chain, the renal injury in this patient was mild. After treatment with four courses of BD, one course of PAD, and autologous stem cell transplantation, he achieved a very good partial hematologic response with stable renal function. CONCLUSIONS: In multiple myeloma, the light chain reaches a certain level and persists, resulting in C3GN renal impairment. Early diagnosis and early intensive treatment are critical for the prognosis of such patients.


Asunto(s)
Glomerulonefritis , Trasplante de Células Madre Hematopoyéticas , Mieloma Múltiple , Humanos , Masculino , Persona de Mediana Edad , Mieloma Múltiple/complicaciones , Pronóstico , Trasplante Autólogo
11.
Ecotoxicol Environ Saf ; 220: 112329, 2021 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-34020282

RESUMEN

Studying the characteristics of new particle formation (NPF) is conducive to exploring the impact of atmospheric particulate matter on the climate, environment, and human health. The particle number size distributions (5.6-560 nm) of aerosols were measured using a fast mobility particle sizer (FMPS) from 1 to 11 May 2019. The clean atmosphere was one of the basic conditions for the occurrence of this continuous new particle formation events. It started between 9:00 and 12:00, and it mainly ended after 20:00. The growth rate (GR) and condensation sink (CS) values in Hefei were 2.98 ± 0.97 nm·h-1 and (3.0 ± 0.4) × 10-2 s-1, respectively. Back trajectory clustering analysis revealed that the mass concentration of the air masses from the southeastern part of Henan Province and the southern part of Anhui Province surrounding the study area were relatively high. The analysis results of the potential source contribution function (PSCF) and the concentration weighted trajectory (CWT) methods show that in addition to local pollution, the long-distance transport of pollutants in the Yangtze River Delta (YRD) greatly contributed to the accumulation modal particulate concentration in Hefei. Moreover, the population affected by PM2.5 during the observation period reached 8.19 × 104, accounting for 1.08% to the total population in Hefei. The premature death cases associated with PM2.5 reached 8.35 × 102. This study is helpful to understand the main influencing factors of consecutive NPF events and the health risks of fine particles.


Asunto(s)
Aerosoles/análisis , Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis , Monitoreo del Ambiente , Material Particulado/análisis , China , Vacaciones y Feriados
12.
Ecotoxicol Environ Saf ; 169: 470-478, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30472471

RESUMEN

Atmospheric polycyclic aromatic hydrocarbons (PAHs) emitted from coal combustion has become the major contributor of atmospheric PAHs in China and caused worldwide concern due to their adverse effects on human health and ecosystem. In this work, the abundance, distribution, source and health risk assessment of ambient PM10-bounded PAHs were studied in all seasons from a typical coal resource city in China. The spatial distribution characteristics of PM10-bounded PAHs were also investigated, which cover 6 functional zones including industrial area, mining area, commercial district, education area, residential area and control area, respectively. The average concentrations (in ng/m3) of 16 EPA priority PAHs in PM10 in spring, summer, autumn and winter were 194 ±â€¯11.1, 161 ±â€¯14.0, 183 ±â€¯14.1 and 213 ±â€¯19.2, respectively, and with an annual average of 188 ±â€¯21.8. The composition distribution of PM10-bounded PAHs in each functional zone showed that 4-rings PAHs were dominated in all seasons, followed by 3-rings and 5-rings. Principal component analysis (PCA) and diagnostic ratio indicated that the main PAH sources were coal combustion, traffic and biomass combustion. Health risk assessment analysis (BEQ) suggested that the residential exposure to PAHs in the mining and commercial areas, particularly in winter season, may pose a greater cancer risk than people living in other parts of Huainan city. The maximum BEQ values were found at mining and commercial areas, which were mainly influenced by the emissions from gasoline or diesel vehicles, coal and biomass combustion. Both inhalation and skin contact have great influence on the cancer risk of residents in Huainan city.


Asunto(s)
Contaminantes Atmosféricos/análisis , Minas de Carbón , Monitoreo del Ambiente/métodos , Material Particulado/análisis , Hidrocarburos Policíclicos Aromáticos/análisis , China , Ciudades , Carbón Mineral/análisis , Humanos , Industrias , Tamaño de la Partícula , Medición de Riesgo , Estaciones del Año
13.
Sensors (Basel) ; 19(16)2019 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-31426315

RESUMEN

Fiber-reinforced polymer (FRP) composites have been widely employed to design advanced structural columns such as the hybrid FRP-concrete-steel double-skin tubular column (hybrid DSTC) with potential benefits. To date, the safety and self-monitoring of the hybrid DSTCs are still a challenge to overcome due to the complex damage scenarios. This paper investigates the self-sensing performance of a newly developed smart double-skin tubular confined concrete column (smart BFST-DSTC) made of basalt FRP-steel composite with built-in optical fiber Bragg grating sensors (OFBGs). The design of the smart BFST-DSTC and sensing principle are firstly addressed, followed by an experimental investigation on the basic mechanical properties and strain-based sensing performance of ten scaled specimens under axial compression. The outcomes reveal the enhancement of the proposed column in terms of load-carrying capacity, confinement ratio, and axial stress-axial strain behavior, as well as failure and damage modes when compared with the hybrid DSTC. The self-sensing investigation demonstrates that the measurement range satisfies the requirement to monitor and evaluate the hoop strains of the FRP jackets and the health state of the inner tube. The smart BFST-DSTC can replace the hybrid DSTC with the ability to provide early failure warning and life cycle health monitoring.

14.
Bull Environ Contam Toxicol ; 103(1): 10-15, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30725130

RESUMEN

In this study, the provenance of anthropogenic lead, a major pollutant of surface sediments, was determined in Huainan Panji coal mining area. The lead concentrations and the pollution degree were investigated by the enrichment factor. Tessier five-step morphology extraction method was used to discuss its potential hazard. By comparing the lead isotope ratios of surface sediments and surrounding potential polluted end-members, the lead isotope ternary mixture model was appropriated to explore the sources and relative contribution fractions. The results showed that: (1) The lead concentrations ranged from 31.44 to 64.07 mg/kg which was mild-moderate pollution. (2) The chemical forms of lead were residue state > iron-manganese oxidation state > exchangeable state > organic state > carbonate state. (3) The anthropogenic lead in surface sediments originated from soil, vehicle exhaust, coal gangue. And the relative contribution fractions were 51.70%, 30.90%, and 17.40%.


Asunto(s)
Monitoreo del Ambiente/métodos , Plomo/análisis , Contaminantes del Suelo/análisis , China , Carbón Mineral/análisis , Minas de Carbón , Contaminación Ambiental/análisis , Sedimentos Geológicos/química , Isótopos , Metales Pesados/análisis , Suelo/química , Emisiones de Vehículos/análisis
15.
Sensors (Basel) ; 18(12)2018 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-30486264

RESUMEN

This paper presents a concept of a Self-sensing Carbon Fiber Reinforced Polymer (SCFRP) system, which integrates the piezoceramic transducers with the common concrete strengthening materials, CFRP fabric. This integration provides the SCFRP fabric with the ability to monitor the structural health condition when the SCFRP fabric is applied on reinforced concrete structures. In order to validate the feasibility of this system, several three-point bending beam (3PBB) specimens were fabricated and tested before and after the specimens were reinforced with the proposed SCFRP fabric. In addition, the specimens with the low (C25) and high (C40) concrete grades were also experimentally investigated to evaluate the reinforced effectiveness of the SCFRP fabric. Finally, the experimental results demonstrate that the proposed SCFRP fabric can significantly improve the bearing capacity of the concrete structures, and provided the reinforced concrete structures with an ability of self-sensing their health condition.

16.
Sensors (Basel) ; 18(11)2018 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-30469335

RESUMEN

Concrete compressive strength is an important parameter of material properties for assessing seismic performance of reinforced concrete (RC) structures, which has a certain level of uncertainty due to its inherent variability. In this paper, the method of concrete strength validation of finite element model using smart aggregate (SA)-based stress monitoring is proposed. The FE model was established using Open System for Earthquake Engineering Simulation (OpenSEES) platform. The concrete strengths obtained from the material test, peak stress of SA, and estimated concrete strength based on SA stress were employed in FE models. The lateral displacement monitored by Liner variable differential transformer and vertical axial load monitored by load cell in the experiment are applied in the model. By comparing the global response (i.e., lateral reaction force and hysteretic loop), local response (i.e., concrete stress, rebar strain, and cross-section moment) and corresponding root-mean-square error obtained from experiment and numerical analysis, the capabilities of validation of FE model using SA-based stress monitoring method were demonstrated.

17.
Br J Haematol ; 169(6): 834-42, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25824806

RESUMEN

This study retrospectively collected the clinical and laboratory data of 114 patients with Castleman disease (CD) from a single medical centre. Clinical classification identified 62 patients (54·4%) with unicentric Castleman disease and 52 (45·6%) with multi-centric Castleman disease. Pathological classification revealed 68 cases (59·6%) of hyaline vascular variant, 16 (14·1%) mixed cellular variant (Mix) and 30 (26·3%) plasmacytic variant. Clinical complications occurred in 69 CD patients, including 37 cases of paraneoplastic pemphigus (PNP) and 25 cases with renal complications. Haematological involvement, pleural effusion and/or ascites and POEMS syndrome (polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy and skin changes) were also found. Univariate analysis showed that presence of clinical complications and PNP were both risk factors relating to CD patient survival. Prognostic factors showing P < 0·15 in univariate analysis and those with clinical significance were subjected to multivariate analysis using a Cox regression model. PNP presence and age over 40 years both significantly adversely affected survival. Thus, only presence of PNP was identified as an independent unfavourable survival risk factor in both univariate and multivariate analyses. Overall, the present data provide a panoramic description of CD cases and emphasize that the presence of PNP is an adverse prognostic factor.


Asunto(s)
Enfermedad de Castleman/diagnóstico , Adolescente , Adulto , Factores de Edad , Anciano , Enfermedad de Castleman/complicaciones , Enfermedad de Castleman/mortalidad , Enfermedad de Castleman/terapia , Niño , Femenino , Estudios de Seguimiento , Centro Germinal/patología , Humanos , Masculino , Persona de Mediana Edad , Síndromes Paraneoplásicos/diagnóstico , Síndromes Paraneoplásicos/etiología , Pénfigo/diagnóstico , Pénfigo/etiología , Pronóstico , Estudios Retrospectivos , Factores de Riesgo , Adulto Joven
18.
ScientificWorldJournal ; 2014: 840283, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25243231

RESUMEN

The dynamic responses of mooring line serve important functions in the station keeping of a floating wind turbine (FWT). Mooring line damping significantly influences the global motions of a FWT. This study investigates the estimation of mooring line damping on the basis of the National Renewable Energy Laboratory 5 MW offshore wind turbine model that is mounted on the ITI Energy barge. A numerical estimation method is derived from the energy absorption of a mooring line resulting from FWT motion. The method is validated by performing a 1/80 scale model test. Different parameter changes are analyzed for mooring line damping induced by horizontal and vertical motions. These parameters include excitation amplitude, excitation period, and drag coefficient. Results suggest that mooring line damping must be carefully considered in the FWT design.


Asunto(s)
Centrales Eléctricas/instrumentación , Energía Renovable , Viento
19.
Sensors (Basel) ; 14(3): 4364-83, 2014 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-24603635

RESUMEN

Fatigue, a hot scientific research topic for centuries, can trigger sudden failure of critical structures such as aircraft and railway systems, resulting in enormous casualties as well as economic losses. The fatigue life of certain structures is intrinsically random and few monitoring techniques are capable of tracking the full life-cycle fatigue damage. In this paper, a novel in-situ wireless real-time fatigue monitoring system using a bio-inspired tree ring data tracking technique is proposed. The general framework, methodology, and verification of this intelligent system are discussed in details. The rain-flow counting (RFC) method is adopted as the core algorithm which quantifies fatigue damages, and Digital Signal Processing (DSP) is introduced as the core module for data collection and analysis. Laboratory test results based on strain gauges and polyvinylidene fluoride (PVDF) sensors have shown that the developed intelligent system can provide a reliable quick feedback and early warning of fatigue failure. With the merits of low cost, high accuracy and great reliability, the developed wireless fatigue sensing system can be further applied to mechanical engineering, civil infrastructures, transportation systems, aerospace engineering, etc.


Asunto(s)
Análisis de Falla de Equipo/métodos , Procesamiento de Señales Asistido por Computador , Estrés Mecánico , Árboles/anatomía & histología , Tecnología Inalámbrica , Algoritmos , Calibración , Simulación por Computador , Polivinilos/química , Programas Informáticos
20.
Zhonghua Nei Ke Za Zhi ; 53(5): 394-7, 2014 May.
Artículo en Zh | MEDLINE | ID: mdl-25146408

RESUMEN

OBJECTIVE: To analyze the clinical characteristics of polyserositis associated with chronic graft-versus-host disease (cGVHD) after allogeneic hematopoietic transplantation(allo-HSCT). METHODS: The occurrence rate and severity of cGVHD in 323 patients who received allo-HSCT in Peking University First Hospital from June 2003 to July 2013 were observed. Their clinical characteristics and therapeutic effect on polyserositis were analyzed as well. RESULTS: Of the 294 patients who survived for more than 100 days after allo-HSCT, 90 patients (30.6%) were diagnosed with cGVHD including extensive cGVHD in 25 patients (8.5%). Among the patients with cGVHD, 4 patients (4.4%) developed moderate to large amount of polyserous effusions. All of these 4 patients had extensive cGVHD. The effusion was proved to be transudate or transudate-exudate. Immunosuppressive treatment was effective but unsustainable. CONCLUSIONS: Polyserositis with large amount of effusion might be a rare manifestation of cGVHD and is refractory. When recurrent polyserous effusion presents with cGVHD after allo-HSCT, it should be considered as a manifestation of extensive cGVHD. Appropriate treatment should be given immediately.


Asunto(s)
Enfermedad Crónica/tratamiento farmacológico , Enfermedad Injerto contra Huésped/diagnóstico , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Inmunosupresores/uso terapéutico , Derrame Pleural/etiología , Adolescente , Enfermedad Injerto contra Huésped/complicaciones , Enfermedad Injerto contra Huésped/tratamiento farmacológico , Humanos , Derrame Pleural/tratamiento farmacológico , Trasplante Homólogo , Resultado del Tratamiento
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA