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1.
Nanomaterials (Basel) ; 9(9)2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31540363

RESUMO

This study introduces a method of patterning carbon nanotube (CNTs) forests that is both fast and simple. We found that, as commercially available oil-based markers undergo nanotube synthesis, a thin film forms that prevents the catalyst, ferrocene, from coming into contact with the surface of the test sample. This, thus, blocks CNT growth. Through further deduction, we used styrene maleic anhydride (SMA) to conduct CNT patterning, in addition to analyzing the relationship between the weight percent concentration of the SMA and the extent to which it blocked CNT growth. We developed two separate methods for applying ink to soft and hard substrates: one method involved ink printing and the other laser stripping. In the CNT pattern we produced, a minimum line width of around 10 µm was attained.

2.
Nanomaterials (Basel) ; 9(5)2019 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-31108887

RESUMO

Vertically-aligned carbon nanotube forests (VACNTs) with excellent axial heat dissipation properties were formed on aluminum foil to dissipate heat. In addition, the heat dissipation efficiency of aluminum-VACNTs composites in this work was compared with that of commercially available mainstream thermal sheets under the same natural cooling conditions. Chemical vapor deposition (CVD) was employed as a synthesis method using a three-segment high-temperature furnace. Subsequently, the temperature changes in a heating body with the aluminum-VACNTs composites was measured over time subject to natural cooling. In addition, the performance was compared with copper and pyrolytic graphite sheets. The experimental results revealed that the heat dissipation efficiency of the flexible aluminum-VACNTs composites was higher than that of clean aluminum foil, a copper sheet, and a pyrolytic graphite sheet by up to 56%, 40%, and 20%, respectively. Moreover, this work also verified the height of the carbon nanotube (CNT) did not influence the heat dissipation efficiency, indicating that the time cost of synthesis could be reduced.

3.
Materials (Basel) ; 10(2)2017 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-28772567

RESUMO

We fabricated a 3D sandwich hybrid material composed of graphene and vertically aligned carbon nanotube forests (VACNTs) using chemical vapor deposition. The graphene was first synthesized on Cu foil. Then it was transferred to a substrate which had a pre-deposited catalyst Fe film and a buffer film of Al2O3 for the growth of VACNTs. The VACNTs were grown underneath the graphene and lifted up the graphene. The graphene, with its edges anchored on the Al2O3, provided a constrained boundary condition for the VACNTs and hence affected the growth height and mechanical strength of the VACNTs. We prepared three groups of samples: VACNTs without graphene, VACNTs with graphene transferred once (1-Gr/VACNTs), and VACNTs with graphene transferred twice (2-Gr/VACNTs). A nano-indentation system was used to measure the reduced compressive modulus (Er) and hardness (H). The Er and H of Gr/VACNTs increased with the number of transfers of the anchored graphene. The 2-Gr/VACNTs had the largest Er and H, 23.8 MPa and 912 KPa, which are 6.6 times and 5.2 times those of VACNTs without the anchored graphene, respectively. In this work, we have demonstrated a simple method to increase the mechanical properties and suppress the height of VACNTs with the anchored graphene and number of transfers.

4.
Int J Med Mushrooms ; 18(5): 425-31, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27649604

RESUMO

We investigated the effects of Phellinus linteus extracts (PLEs) against radiation damage in mice. First, BALB/c mice were irradiated once with γ-rays at 4, 5, 6, or 8 Gy and allowed to recover for 20 days. Results reveal that 8-Gy radiation caused death in 100% of mice on day 13, and 6-Gy radiation caused death in 86.7% of mice (13/15) at the end of the experiment, whereas 4- and 5-Gy radiation did not result in any death. We then used 5-Gy γ-ray radiation to examine the protective effects of PLEs. Mice were orally administered a PLE (500, 1000, and 1500 mg/kg) daily for 2 weeks before radiation and for 6 weeks after radiation. γ-Ray radiation significantly decreased body weight starting from week 2 after radiation. Supplementation with a median and high dose of PLE significantly restored body weights starting at weeks 5 and 3, respectively. The radiation-protective agent WR2721 (200 mg/kg intraperitoneally) restored body weights starting at week 4. White blood cells, platelets, red blood cells, and hemoglobin were significantly decreased by radiation, and PLEs (primarily at high doses) and WR2721 significantly prevented hematologic abnormality. These results suggest that PLE has potential as a radioprotective agent.


Assuntos
Agaricales/química , Raios gama/efeitos adversos , Hematopoese/efeitos dos fármacos , Hematopoese/efeitos da radiação , Lesões Experimentais por Radiação/prevenção & controle , Animais , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Protetores contra Radiação/farmacologia , Redução de Peso , Irradiação Corporal Total
5.
Sensors (Basel) ; 15(6): 13670-9, 2015 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-26110400

RESUMO

During dental sinus lift surgery, it is important to monitor the thickness of the remaining maxilla to avoid perforating the sinus membrane. Therefore, a sensor should be integrated into ultrasonic dental tools to prevent undesirable damage. This paper presents a piezoelectric (PZT) sensor installed in an ultrasonic transducer to measure the stiffness of high and low materials. Four design types using three PZT ring materials and a split PZT for actuator and sensor ring materials were studied. Three sensor locations were also examined. The voltage signals of the sensor and the displacement of the actuator were analyzed to distinguish the low and high stiffness. Using sensor type T1 made of the PZT-1 material and the front location A1 provided a high sensitivity of 2.47 Vm/kN. The experimental results demonstrated that our design can measure soft and hard stiffness.


Assuntos
Transdutores , Ultrassonografia/instrumentação , Módulo de Elasticidade , Desenho de Equipamento , Vibração
6.
Sensors (Basel) ; 12(8): 10034-41, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23112586

RESUMO

This work demonstrates a highly sensitive pressure sensor that was fabricated using carbon microcoils (CMCs) and polydimethylsiloxane (PDMS). CMCs were grown by chemical vapor deposition using various ratios of Fe-Sn catalytic solution. The pressure sensor has a sandwiched structure, in which the as-grown CMCs were inserted between two PDMS layers. The pressure sensor exhibits piezo-resistivity changes in response to mechanical loading using a load cell system. The yields of the growth of CMCs at a catalyst proportion of Fe:Sn = 95:5 reach 95%. Experimental results show that the sensor achieves a high sensitivity of 0.93%/kPa from the CMC yield of 95%. The sensitivity of the pressure sensor increases with increasing yield of CMCs. The demonstrated pressure sensor shows the advantage of high sensitivity and is suitable for mass production.

7.
Eur J Radiol ; 81(5): 1024-8, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-21458941

RESUMO

PURPOSE: We conducted this study to investigate the value of the dual-time 2-[(18)F]fluoro-2-deoxy-d-glucose (FDG) positron emission tomography-computed tomography (PET-CT) in assessment of the primary tumor, loco-regional lymph node and distant metastasis in patients with esophageal squamous cell carcinoma. METHODS: Twenty-six patients with histologically proved esophageal squamous cell carcinoma underwent dual-time FDG PET-CT before radical surgery. The standardized uptake values (SUV(max)) were obtained including early SUV(max) and delayed SUV(max), respectively. The retention index (RI) was also calculated. The results were evaluated retrospectively according to the final pathologic findings. Four diagnostic criteria including (1) early SUV(max)≧ 2.5 alone, (2) RI ≧ 10% alone, (3) a combination of early SUV(max)≧ 2.5 and RI ≧ 10%, and (4) a combination of early SUV(max)≧ 2.5 or RI ≧ 10% were used for differentiating malignancy from a benign lesion, respectively. RESULTS: The sensitivity of FDG PET-CT in detecting the primary tumor with combination of early SUV(max)≧ 2.5 or RI ≧ 10% was 96.2%. It was statistically significantly higher than the results using the other three criteria (p<0.0001). For loco-regional lymph node detection, there was no significant difference among the 4 criteria. For distal metastases, the significantly higher specificity (100%) was found when using combination of early SUV(max)≧ 2.5 and RI ≧ 10% or using early SUV(max)≧ 2.5 alone than using the other two criteria (p=0.0058). With regard to accuracy, no significant correlations were observed among primary tumor, loco-regional lymph nodes and distant metastasis (p>0.05). CONCLUSION: The preliminary result of this study demonstrated that dual-time point FDG PET-CT had limited value in detection of primary tumor and loco-regional lymph nodes metastasis. For the distant metastasis, the sensitivity and specificity would be improved if RI ≧ 10% is used as a supplemental criterion. Efforts should be made to improve the ability of the dual-time FDG PET-CT technique to assess primary tumor and loco-regional lymph nodes metastasis.


Assuntos
Carcinoma de Células Escamosas/diagnóstico , Neoplasias Esofágicas/diagnóstico , Neoplasias Esofágicas/secundário , Fluordesoxiglucose F18 , Tomografia por Emissão de Pósitrons/métodos , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Feminino , Humanos , Linfonodos/diagnóstico por imagem , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Técnica de Subtração
8.
Nucleic Acids Res ; 38(18): 6148-58, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20494979

RESUMO

Carcinogenesis is determined based on both cell proliferation and death rates. Recent studies demonstrate that heat shock proteins (HSPs) regulate apoptosis. HLJ1, a member of the DnaJ-like Hsp40 family, is a newly identified tumor suppressor protein closely related to relapse and survival in non-small cell lung cancer (NSCLC) patients. However, its role in apoptosis is currently unknown. In this study, NSCLC cell lines displaying varying HLJ1 expression levels were subjected to ultraviolet (UV) irradiation, followed by flow cytometry. Interestingly, the percentages of apoptotic cells in the seven cell lines examined were positively correlated with HLJ1 expression. Enforcing expression of HLJ1 in low-HLJ1 expressing highly invasive cells promoted UV-induced apoptosis through enhancing JNK and caspase-3 activation in NSCLC. Additionally, UV irradiation led to reduced levels of HLJ1 predominantly in apoptotic cells. The pan-caspase inhibitor, zVAD-fmk and caspase-3-specific inhibitor, DEVD-fmk, prevented UV-induced degradation of HLJ1 by the late stage of apoptosis. Further experiments revealed a non-typical caspase-3 cleavage site (MEID) at amino acid 125-128 of HLJ1. Our results collectively suggest that HLJ1 is a novel substrate of caspase-3 during the UV-induced apoptotic process.


Assuntos
Apoptose , Carcinoma Pulmonar de Células não Pequenas/enzimologia , Caspase 3/metabolismo , Proteínas de Choque Térmico HSP40/metabolismo , Neoplasias Pulmonares/enzimologia , Raios Ultravioleta , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia
9.
Kaohsiung J Med Sci ; 25(3): 145-50, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19419920

RESUMO

Patients with head and neck cancer have a greater risk of developing second primary malignant neoplasms than patients with any other type of malignancy. Small cell neuroendocrine carcinoma (SNEC) mainly occurs in the lung, and is rarely found in the head and neck region. Only a few cases of sinonasal SNEC have been reported in the English literature. A woman aged 53 years, who had undergone successful curative radiotherapy for nasopharyngeal carcinoma 10 years earlier, presented with a history of bleeding from the left nostril for several weeks. A computed tomography scan of the head and neck showed a mass in the left nasal cavity with extension into the maxillary sinus. A biopsy specimen was taken and pathology revealed SNEC. The patient underwent a full course of concurrent chemoradiotherapy. No local recurrence or distant metastasis was noted during the 12 months of follow-up.


Assuntos
Carcinoma Neuroendócrino/diagnóstico por imagem , Neoplasias Nasofaríngeas/radioterapia , Segunda Neoplasia Primária/radioterapia , Feminino , Humanos , Pessoa de Meia-Idade , Radiografia , Resultado do Tratamento
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