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2.
Materials (Basel) ; 16(9)2023 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-37176458

RESUMO

The appearance of cracks is one of the reasons that affect the performance of asphalt pavement, and traditional repair methods have the potential problem of causing adverse effects on the environment. In this paper, an environmentally friendly method for asphalt concrete crack repair was investigated using microbially induced calcite precipitation (MICP) for asphalt concrete cracks of different widths (0.5 mm, 1.0 mm, 1.5 mm, and 3 mm), and the effectiveness of repair was evaluated using nondestructive and destructive experiments. A varied ultrasonic pulse velocity was used to evaluate the healing process, and it was found that the samples with an initial crack width of 0.5 mm showed the most significant increase in wave velocity of 18.06% after repair. The results also showed that the uniaxial compressive strength and indirect tensile strength of the MICP-repaired samples recovered up to 47.02% and 34.68%. Static creep test results showed that MICP-repaired samples with smaller width cracks had greater resistance to permanent deformation. The results of uniaxial compressive strength tests on larger width (3 mm) cracks repaired by MICP combined with fibers showed that the strength of the samples was significantly increased by the addition of fibers. In addition, the SEM/EDS results showed that the MICP products were spherical calcite particles with a particle size distribution from 0 to 10 µm. This study shows that MICP has some potential for repairing cracks in asphalt concrete of different widths within the range investigated.

4.
Nat Sci Sleep ; 12: 783-790, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33117014

RESUMO

BACKGROUND: Unfavorable sleep habits have been linked with ischemic stroke in observational studies, but the causality remains unclear. The aim of this study is to investigate the potential causal role of three sleep traits, including sleep duration, insomnia, and chronotype, in ischemic stroke and its subtypes. METHODS: We conducted two-sample Mendelian randomization (MR) analysis using single nucleotide polymorphisms associated with sleep duration, insomnia, and chronotype as instruments to estimate causal associations with ischemic stroke and its subtypes, among 34,217 ischemic stroke cases and 406,111 controls from the MEGASTROKE consortium. Inverse-variance weighted method was used as the main analyses. Alternative MR methods and sensitivity analyses were further performed. RESULTS: We found suggestive evidence that per doubling of genetic liability for short sleep duration (odds ratio [OR], 1.27; 95% confidence interval [CI], 1.01-1.58) and frequent insomnia symptoms (OR, 1.19; 95% CI, 1.00-1.41) were associated with a modest increase in risk of large artery stroke (LAS) but not with small vessel stroke, cardioembolic stroke, or any ischemic stroke. The association of frequent insomnia symptoms with LAS was stronger after the exclusion of the outlier (OR, 1.25; 95% CI, 1.04-1.50). No significant association was observed for chronotype with any ischemic stroke subtype. Results were overall robust to sensitivity analyses, and there was little evidence of horizontal pleiotropy. CONCLUSION: We provided suggestive evidence for a potential causal role of short sleep duration and insomnia symptoms in LAS. Future researches are required to investigate whether improved sleep habits could help to mitigate LAS risk.

5.
IEEE Trans Image Process ; 26(3): 1243-1252, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28092537

RESUMO

Multi-scale exposure fusion is an effective image enhancement technique for a high dynamic range (HDR) scene. In this paper, a new multi-scale exposure fusion algorithm is proposed to merge differently exposed low dynamic range (LDR) images by using the weighted guided image filter to smooth the Gaussian pyramids of weight maps for all the LDR images. Details in the brightest and darkest regions of the HDR scene are preserved better by the proposed algorithm without relative brightness change in the fused image. In addition, a new weighted structure tensor is introduced to the differently exposed images and it is adopted to design a detail extraction component for the proposed fusion algorithm, such that users are allowed to manipulate fine details in the enhanced image according to their preference. The proposed multi-scale exposure fusion algorithm is also applied to design a simple single image brightening algorithm for both low-light imaging and back-light imaging.

6.
Zhongguo Zhen Jiu ; 36(10): 1031-1035, 2016 Oct 12.
Artigo em Chinês | MEDLINE | ID: mdl-29231521

RESUMO

OBJECTIVE: To compare the efficacy difference between acupotomy and acupuncture in the treatment of avascular necrosis of femoral head at the early and middle stages. METHODS: The randomized controlled prospective study method was adopted. Sixty cases of avascular necrosis of femoral head at Ficat-ArletⅠto Ⅱ stages were randomized into an acupotomy group (32 cases) and an acupuncture group (28 cases) by the third part. In the acupotomy group, the acupotomy was adopted for the loose solution at the treatment sites of hip joint, once every two weeks, totally for 3 times. In the acupuncture group, ashi points around the hip joint were selected and stimulated with warm acupuncture therapy, once every day, for 6 weeks. Harris hip score was observed before and after treatment. The efficacy was evaluated in the two groups. RESULTS: Harris hip score was improved significantly after treatment in the two groups (both P<0.05). The result in acupotomy group was better than that in the acupuncture group (P<0.05). The effective rate was 90.6% (29/32) in the acupotomy group, better than 75.0% (21/28) in the acupuncture group after treatment (P<0.05). CONCLUSIONS: Harris hip score and the effective rate in the acupotomy group are better than those in the treatment with routine acupuncture for avascular necrosis of femoral head at the early and middle stages.


Assuntos
Terapia por Acupuntura/métodos , Necrose da Cabeça do Fêmur/terapia , Necrose da Cabeça do Fêmur/patologia , Humanos , Estudos Prospectivos , Projetos de Pesquisa , Resultado do Tratamento
7.
Zhonghua Fu Chan Ke Za Zhi ; 50(8): 582-5, 2015 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-26675180

RESUMO

OBJECTIVE: To evaluate the feasibility and safety of transabdominal ultrasound-guided suction curettage to treat cesarean scar pregnancy (CSP) and investigate factors affecting prognosis of CSP. METHODS: This was a retrospective case study of 43 cases who were diagnosed as CSP and treated by suction curettage under transabdominal ultrasound guidance as an initial treatment of CSP in Obstetrics and Gynecology Hospital of Fudan University over past 7 years (from 2007 to 2013); factors affecting prognosis of CSP were investigated. RESULTS: 39 of the 43 cases (91%) were successfully treated. There were no statistically significant differences in maternal age, gravidity, abortion frequency, and the time interval between current CSP and last cesarean delivery, the myometrium thickness between the gestational sac and the bladder wall between the success group and the failure group (all P > 0.05). Statistically significant difference was found in crown-rump length (CRL) between the two group (median of the two group was 18.5, 2.0 mm) by rank sum test (P = 0.047). Univariate logistic regression analysis demonstrated that CRL was strongly associated with the prognosis and the OR for no complications was 18.50, comparing CRL ≤ 6 mm versus CRL > 6 mm (P = 0.020). CONCLUSION: Transabdominal ultrasound-guided suction curettage is effective and safe in the treatment of CSP with CRL ≤ 6 mm.


Assuntos
Cesárea/efeitos adversos , Cicatriz/etiologia , Cicatriz/cirurgia , Gravidez Ectópica/cirurgia , Ultrassonografia/métodos , Curetagem a Vácuo/métodos , Aborto Induzido , Cicatriz/complicações , Estatura Cabeça-Cóccix , Estudos de Viabilidade , Feminino , Humanos , Idade Materna , Gravidez , Estudos Retrospectivos , Resultado do Tratamento
8.
IEEE Trans Image Process ; 24(12): 5432-41, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26441415

RESUMO

Single image haze removal is under-constrained, because the number of freedoms is larger than the number of observations. In this paper, a novel edge-preserving decomposition-based method is introduced to estimate transmission map for a haze image so as to design a single image haze removal algorithm from the Koschmiedars law without using any prior. In particular, weighted guided image filter is adopted to decompose simplified dark channel of the haze image into a base layer and a detail layer. The transmission map is estimated from the base layer, and it is applied to restore the haze-free image. The experimental results on different types of images, including haze images, underwater images, and normal images without haze, show the performance of the proposed algorithm.

9.
IEEE Trans Image Process ; 24(1): 120-9, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25415986

RESUMO

It is known that local filtering-based edge preserving smoothing techniques suffer from halo artifacts. In this paper, a weighted guided image filter (WGIF) is introduced by incorporating an edge-aware weighting into an existing guided image filter (GIF) to address the problem. The WGIF inherits advantages of both global and local smoothing filters in the sense that: 1) the complexity of the WGIF is O(N) for an image with N pixels, which is same as the GIF and 2) the WGIF can avoid halo artifacts like the existing global smoothing filters. The WGIF is applied for single image detail enhancement, single image haze removal, and fusion of differently exposed images. Experimental results show that the resultant algorithms produce images with better visual quality and at the same time halo artifacts can be reduced/avoided from appearing in the final images with negligible increment on running times.

10.
IEEE Trans Image Process ; 23(10): 4372-82, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25148667

RESUMO

In this paper, we introduce an exposure fusion scheme for differently exposed images with moving objects. The proposed scheme comprises a ghost removal algorithm in a low dynamic range domain and a selectively detail-enhanced exposure fusion algorithm. The proposed ghost removal algorithm includes a bidirectional normalization-based method for the detection of nonconsistent pixels and a two-round hybrid method for the correction of nonconsistent pixels. Our detail-enhanced exposure fusion algorithm includes a content adaptive bilateral filter, which extracts fine details from all the corrected images simultaneously in gradient domain. The final image is synthesized by selectively adding the extracted fine details to an intermediate image that is generated by fusing all the corrected images via an existing multiscale algorithm. The proposed exposure fusion algorithm allows fine details to be exaggerated while existing exposure fusion algorithms do not provide such an option. The proposed scheme usually outperforms existing exposure fusion schemes when there are moving objects in real scenes. In addition, the proposed ghost removal algorithm is simpler than existing ghost removal algorithms and is suitable for mobile devices with limited computational resource.

11.
IEEE Trans Image Process ; 22(12): 5190-201, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24108466

RESUMO

It is very challenging to synthesize a high dynamic range (HDR) image from multiple differently exposed low dynamic range images when there are moving objects in the images. This is due to the fact that the moving objects will cause ghosting artifacts to appear in the synthesized HDR image. To prevent such artifacts, a patching algorithm is required to correct motion regions such that all the moving objects are synchronized in the differently exposed images. In this paper, a new optimization problem is formulated to correct the motion regions of the multiple differently exposed images by considering both spatial and temporal consistencies. The resultant scheme is a hybrid patching scheme composed of a correction method which is an intensity mapping function at pixel level, and a hole-filling method that uses block-level template matching. The proposed patching scheme is not only robust to large intensity changes in these input images, but also at regions that are over- or underexposed. Experimental results show that the proposed method is able to prevent ghosting artifacts from appearing in the final synthesized HDR image.

12.
Zhonghua Fu Chan Ke Za Zhi ; 45(7): 519-24, 2010 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-21029605

RESUMO

OBJECTIVE: To establish a satisfactory lung metastasis model of human choriocarcinoma using severe combined immunodeficient (SCID) mice and explore the appropriate cell concentration for the model. METHODS: Forty SCID mice aged between 5 - 6 weeks were randomly divided into four groups. 1 × 10(7) cells/ml × 0.1 ml, 5 × 10(6) cells/ml × 0.2 ml and 1 × 10(6) cells/ml × 0.1 ml of human choriocarcinoma cells JEG-3 were respectively injected in SCID mice of experimental groups by lateral tail vein, the remain group was assigned to the control group. The status and weight of mice were observed every three days. When these mice were being dying, the size and the number of the lesions of lung metastasis in every mouse were inspected with Micro CT. After Micro CT inspection, the SCID mice were executed dissected to note whether there were tumors on all organ surfaces with naked eyes, then made pathological sections from the metastatic foci of fresh lung tissues, and cultured primarily cells and purified cells and passaged cells isolated from the same metastastic foci. The pathological sections were observed under the microscope. The special antigen human chorionic gonadotropin-beta subunit (ß-hCG) of the choriocarcinoma cells was immunohistochemically detected in the pathological sections and the cells out of cultured primarily cells. The chromosomes of the cells out of cultured primarily cells were analysed. RESULTS: Of the group inoculated 1 × 10(7) cells/ml × 0.1 ml, all mice died when inoculating. In the group of 5 × 10(6) cells/ml × 0.2 ml, when inoculating, 3 mice died; the remain 7 mice were being dying on (18.0 ± 2.0) days after injection. 5 of them, there were 1 - 3 lesions of lung metastasis after Micro CT inspection in each mice, and the diameter of the tumors lesions reached 1.5 - 3.5 mm, which was choriocarcinoma confirmed by pathological sections. The special antigen ß-hCG was detected by immunohistochemical method in the pathological sections of pulmonary tissue with tumor and in the cells, which were purified and passaged from being cultured primarily cells isolated from metastastic foci of fresh lung tissues from the SCID mice. The chromosome numbers of these cells out of cultured primarily cells were variety from 19 to 128, and modal numbers were variety from 70 to 79. CONCLUSIONS: We successfully established the lung metastatic model of human choriocarcinoma in SCID mice by injecting JEG-3 cells into lateral tail vein, of which 5 × 10(6) cells/ml × 0.2 ml is the suitable concentration and volume for the model.


Assuntos
Coriocarcinoma/patologia , Gonadotropina Coriônica Humana Subunidade beta/metabolismo , Modelos Animais de Doenças , Neoplasias Pulmonares/secundário , Animais , Índice de Massa Corporal , Linhagem Celular Tumoral , Aberrações Cromossômicas , Feminino , Humanos , Imuno-Histoquímica , Cariotipagem , Pulmão/patologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Camundongos , Camundongos SCID , Metástase Neoplásica , Transplante de Neoplasias , Coloração e Rotulagem
13.
Zhonghua Fu Chan Ke Za Zhi ; 43(12): 892-6, 2008 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-19134325

RESUMO

OBJECTIVE: To establish the high-performance liquid chromatography (HPLC) method for measuring concentrations of methotrexate (MTX) in rat lung and some other tissues through internal iliac artery infusion. METHODS: Fifty female Sprague-Dawley rats were included in this study. The rats were randomly assigned to two groups. Methotrexate was injected to group one through internal iliac artery, and was injected to group two through femoral vein. Blood and tissues were collected in each group at 15, 30, 60, 90 and 120 minutes for detection of the drug concentrations with HPLC. RESULTS: The area under the concentration time curve (AUC) in rat lung, ovary and uterus in the artery group were separately (3.77 +/- 0.28), (4.40 +/- 0.40), (9.97 +/- 0.89) microgxh(-1)xg(-1), which were significantly different from those of the vein group [(2.31 +/- 0.25), (3.91 +/- 0.19), (7.65 +/- 1.54) microgxh(-1)xg(-1); P < 0.05]. The AUC in the rat plasma, heart, kidney, liver and spleen in the artery group were separately (6.13 +/- 0.53), (1.90 +/- 0.11), (5.32 +/- 0.89), (14.16 +/- 1.96), (0.76 +/- 0.20) microgxh(-1)xg(-1). There were no significant differences from the vein group [(5.79 +/- 0.71), (1.64 +/- 0.29), (5.15 +/- 1.69), (14.29 +/- 3.47), (0.76 +/- 0.13) microgxh(-1)xg(-1); P > 0.05]. CONCLUSIONS: Through internal iliac artery infusion, there are higher drug concentrations in lung, uterus and ovarian compared to venous injection. The internal-arterial chemotherapy may be used to treat pulmonary metastasis of gynecological tumor.


Assuntos
Neoplasias dos Genitais Femininos/tratamento farmacológico , Infusões Intra-Arteriais , Pulmão/metabolismo , Metotrexato/farmacocinética , Ovário/metabolismo , Animais , Área Sob a Curva , Cromatografia Líquida de Alta Pressão , Feminino , Neoplasias dos Genitais Femininos/patologia , Artéria Ilíaca , Infusões Intravenosas , Rim/metabolismo , Fígado/metabolismo , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/secundário , Metotrexato/administração & dosagem , Metotrexato/sangue , Ratos , Ratos Sprague-Dawley , Distribuição Tecidual , Útero/metabolismo
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