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In the design of metasurfaces, integrating multiple tasks into a single small unit cell and achieving regulation through various paths pose a serious challenge. In this paper, a multipath-controlled bidirectional metasurface (MCBM) is designed to achieve polarization regulation, perfect absorption and total reflection as multitasking functions. The findings demonstrate that under different excitation conditions, when co-planar polarized terahertz (THz) waves are incident normally on the metasurface, the MCBM can convert co-planar polarization to cross-polarization, co-planar polarization to circular polarization wave in reflection mode, and co-planar polarization to cross-polarization in transmission, respectively. When co-planar polarized THz waves are incident from the back side of the metasurface, the tasks of MCBM change to broadband perfect absorption, total reflection, and transmission co-planar polarization to cross-polarization conversion. Remarkably, all operating frequency bands of these tasks are very approximate. Additionally, the multitasking functions can be switched by altering the excitation conditions, and their performance can be regulated through multipath controls, such as the temperature, voltage, and polarization status. Our design provides an effective strategy for multipath-controlled multitasking integrated devices in the THz band.
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The prevalent use of multispectral detection technology makes single-band camouflage devices ineffective, and the investigation of technology for camouflage that combines multispectral bands becomes urgent. The multifunctional-hierarchical flexibility metasurfaces (MHFM) for multispectral compatible camouflage of microwave, infrared, and visible, is proposed, fabricated, and measured. MHFM is primarily composed of an infrared shielding layer (IRSL), a radar absorbing layer (RAL), and a visible color layer (VCL). Among them, IRSL can block thermal infrared detection, and RAL can efficiently absorb microwave band electromagnetic (EM) waves. The VLC can display black (below 28°C), purple (28°Câ¼31°C), green (31°Câ¼33°C), and yellow (above 33°C) at different temperatures to achieve visible camouflage. Simulation results show that MHFM can achieve absorption higher than 90% in the 2.9â¼13.9â GHz microwave band. Theoretically, the emissivity of MHFM in the infrared spectral range 3â¼14â µm is less than 0.34. In addition, the MHFM consists of high-temperature-resistant materials that can be used normally at temperatures up to 175°C, providing excellent high-temperature stability. The measurement results show that the camouflage performance of the MHFM is in excellent agreement with the proposed theory. This study proposes a new method for multispectral camouflage that has broad engineering applications.
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PURPOSE: Incidence of contrast induced nephropathy (CIN) and related risk factors in patients with liver cancer and chronic kidney disease after trans-catheter arterial chemoembolization (TACE) is higher. The purpose of this study was to investigate the feasibility and safety of TACE therapy in such patients. METHODS: A retrospective analysis was performed on 103 patients with liver cancer and chronic kidney disease who underwent TACE treatments. TACE was performed according to Seldinger's technique of arterial embolization with minor modifications. Based on CIN diagnostic criteria, patients were divided into non-CIN (n=89) and CIN (n=14) groups. Multiple clinical parameters were assessed for the two groups after TACE. Serum creatinine levels were measured 48-72 h after TACE. RESULTS: Tumor size (>5 cm), TACE frequency, contrast agent dosage, solitary kidney, volume of iodized oil used in the TACE (ml) and urea levels were significantly higher in CIN group in comparison with the non-CIN group, while serum albumin and haemoglobin levels were significantly lower. Multivariate logistic regression analysis confirmed that the volume of iodized oil and TACE frequency were significantly positively correlated, and serum albumin level was negatively correlated in the CIN group. CONCLUSION: Volume of iodized oil, TACE frequency and low serum albumin levels were found to be independent risk factors for CIN after TACE. Thus, it is safe and feasible for hepatocellular carcinoma patients with chronic kidney disease to receive TACE treatment, but adverse events management after TACE needs to be addressed.
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Carcinoma Hepatocelular , Quimioembolização Terapêutica , Neoplasias Hepáticas , Insuficiência Renal Crônica , Carcinoma Hepatocelular/terapia , Quimioembolização Terapêutica/efeitos adversos , Meios de Contraste/efeitos adversos , Humanos , Incidência , Neoplasias Hepáticas/terapia , Insuficiência Renal Crônica/complicações , Insuficiência Renal Crônica/terapia , Estudos Retrospectivos , Fatores de RiscoRESUMO
The quantity of absorption bands is traditionally less than the quantity of resonator subunits. Based on the absorption theory of electromagnetic resonance, three-millimeter-wave metamaterial absorbers (MWMAs) based on periodic resonators with double square rings (DSRs) are proposed, discussed, fabricated, and measured. Multiple absorption bands including two, three, and four bands can be effectively achieved by adjusting the dimensions of the DSRs. The electric field distributions at the corresponding resonance frequency can adequately explain the physical mechanism of adjustable absorption bands affected by the strong LC, dipole, and surface responses complexly. Detailed influence produced by sizes and materials is elaborated. The adjustable absorption can be easily scaled to the entire spectrum by geometrical regulation. The presented MWMAs show attractive prospects in electromagnetic devices, biological sensing, material detection, and function materials because of their size adaptation, flexible design, ultrathin thickness, strong flexibility, and convenient fabrication.
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Cell separation has become @important in biological and medical applications. Dielectrophoresis (DEP) is widely used due to the advantages it offers, such as the lack of a requirement for biological markers and the fact that it involves no damage to cells or particles. This study aimed to report a novel approach combining 3D sidewall electrodes and contraction/expansion (CEA) structures to separate three kinds of particles with different sizes or dielectric properties continuously. The separation was achieved through the interaction between electrophoretic forces and inertia forces. The CEA channel was capable of sorting particles with different sizes due to inertial forces, and also enhanced the nonuniformity of the electric field. The 3D electrodes generated a non-uniform electric field at the same height as the channels, which increased the action range of the DEP force. Finite element simulations using the commercial software, COMSOL Multiphysics 5.4, were performed to determine the flow field distributions, electric field distributions, and particle trajectories. The separation experiments were assessed by separating 4 µm polystyrene (PS) particles from 20 µm PS particles at different flow rates by experiencing positive and negative DEP. Subsequently, the sorting performances of the 4 µm PS particles, 20 µm PS particles, and 4 µm silica particles with different solution conductivities were observed. Both the numerical simulations and the practical particle separation displayed high separating efficiency (separation of 4 µm PS particles, 94.2%; separation of 20 µm PS particles, 92.1%; separation of 4 µm Silica particles, 95.3%). The proposed approach is expected to open a new approach to cell sorting and separating.
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The combination of the new perturbed spiral channel and a slanted gold interfingered transducer (IDT) is designed to achieve precise dynamic separation of target particles (20 µm). The offset micropillar array solves the defect that the high-width flow (avoiding the occurrence of channel blockage) channel cannot realize the focusing of small particles (5 µm, 10 µm). The relationship between the maximum design gap of the micropillar (Smax) and the particle radius (a) is given: Smax = 4a, which not only ensures that small particles will not pass through the micropillar gap, but also is compatible with the appropriate flow rates. A non-offset micropillar array was used to remove 20 µm particles in the corner area. The innovation of a spiral channel structure greatly improves the separation efficiency and purity of the separation chip. The separation chip designed by us achieves deflection separation of 20 µm particles at 24.95-41.58 MHz (κ = 1.09-1.81), at a flow rate of 1.2 mL per hour. When f = 33.7 MHz (κ = 1.47), the transverse migration distance of 20 µm particles is the smallest, and the separation purity and efficiency are as high as 92% and 100%, respectively.
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Som , Transdutores , Tamanho da PartículaRESUMO
A dual-band metasurface array is presented in this paper for electromagnetic (EM) energy harvesting in the Wi-Fi band and Ku band. The array consists of metasurface unit cells, rectifiers, and load resistors. The metasurface units within each column are interconnected to establish two channels of energy delivery, enabling the transmission and aggregation of incident power. At the terminals of two channels, a single series diode rectifier and a voltage doubler rectifier are integrated into them to rectify the energy in the Wi-Fi band and the Ku band, respectively. A 7 × 7 prototype of the metasurface array is fabricated and tested. The measured results in the anechoic chamber show that the RF-to-dc efficiencies of the prototype at 2.4 GHz and 12.6 GHz reach 64% and 55% accordingly, when the available incident power at the surface is 3 dBm and 14 dBm, respectively.
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The phase I metabolizing enzyme and phase II metabolizing enzyme play vital roles in carcinogenesis, but little is known about the changes of their activities in patients with hepatocellular carcinoma (HCC) secondary to chronic hepatitis B virus (HBV) infection. In this study phenacetin, a probe drug (1 g for men and 0.85 g for women orally), was applied for the detection of sulfotransferase 1A1 (SULT1A1) and cytochrome P4501A2 (CYP1A2) activities in 82 healthy participants and 148 HCC, 106 cirrhosis, and 41 chronic hepatitis B patients. In addition, a prospective cohort study for susceptibility to HCC was performed in 205 patients with cirrhosis secondary to chronic HBV infection. Compared with the healthy participants, SLUT1A1 activity increased by 9.7-fold in the HCC patients (P < 0.01). CYP1A2 activity did not significantly differ between the healthy participants and HCC patients. CYP1A2 activity decreased by 91.2% (P < 0.01) and 67.7% (P < 0.05) in the patients with cirrhosis and chronic hepatitis B, respectively; SULT1A1 activity did not increase significantly. During an approximate 2-year follow up, three of the 46 cirrhosis patients with elevated SULT1A1 activity and normal CYP1A2 activity developed HCC, but none of the 159 cirrhosis patients used as parallel controls did (P = 0.012). These results indicate that SLUT1A1 activity is dramatically upregulated in patients with HCC secondary to chronic HBV infection. The upregulation of SULT1A1 activity is not caused by the tumor itself. The interaction between SULT1A1 and CYP1A2 can play an important role in hepatocarcinogenesis in the Chinese population.
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Arilsulfotransferase/metabolismo , Carcinoma Hepatocelular/enzimologia , Hepatite B Crônica/complicações , Neoplasias Hepáticas/enzimologia , Acetaminofen/metabolismo , Adulto , Idoso , Carcinoma Hepatocelular/etiologia , Citocromo P-450 CYP1A2/metabolismo , Feminino , Humanos , Cirrose Hepática/enzimologia , Neoplasias Hepáticas/etiologia , Masculino , Pessoa de Meia-Idade , Regulação para CimaRESUMO
BACKGROUND/AIMS: Preoperative portal vein embolization (PVE) allows potentially curative hepatic resection to be carried out in patients with hepatobiliary malignancies who are otherwise not candidates for resection because of the small size of the future liver remnant (FLR). However, there have only been a few reports on PVE before hepatectomy for hilar cholangiocarcinoma due to the small number of patients who can be treated with radical surgery. METHODOLOGY: Between January 2007 and March 2009, 49 consecutive patients with hilar cholangiocarcinoma who were planned to have hemi-hepatectomy/extended hemi-hepatectomy plus caudate lobe resection in our tertiary referral center were studied. The change in size of the FLR and the operative outcomes were compared between patients with or without PVE. RESULTS: All patients had liver dysfunction as a result of biliary obstruction due to hilar cholangiocarcinoma although they had all received percutaneous transhepatic biliary drainage. PVE was used in 16 patients with an estimated FLR of <50%, while no PVE was carried out in 33 patients with an estimated FLR of >50%. Complications after PVE occurred in 3 patients (18.8%), which included bile leakage (n=1) and coil displacement (n=2). No complication precluded liver resection. The FLR to total liver volume (TLV) ratio at presentation was significantly smaller in patients who underwent PVE than those who did not undergo PVE (40.3 +/- 7.4% vs. 56.6 +/- 5.0%; p < 0.001). After PVE, the FLR to TLV ratio increased significantly (40.3 +/- 7.4% vs. 43.1 +/- 7.0%; p < 0.001) at a mean time of 14.2 +/- 3.5 days. The mean +/- S.D. increase in FLR was 4.6 +/- 3.0 cm3/day. At surgery, the FLR volume was still significantly smaller in the PVE group than the non-PVE (802 +/- 216 cm3 vs. 979 +/- 202 cm3; p = 0.007). In the PVE group, insufficient hypertrophy of the FRL prevented one patient from having surgery, while local tumor progression and peritoneal dissemination precluded hepatectomy in 2 more patients. Finally, 13 patients (81.3%) underwent radical surgery. The PVE group had similar complication and mortality rates compared with the non-PVE group (complication rate, 69.2% vs. 63.6%; mortality rate, 0.0% vs. 9.1%). The 1- and 2-year overall survivals for the PVE group (with intent-to-treat analysis), PVE group (radical surgery only) and the non-PVE group were 57.3% and 43.0%; 71.3% and 53.5%; 70.4% and 54.4%, respectively. There was no significant difference in the survival outcomes. CONCLUSIONS: The results suggested that PVE is a safe and efficacious procedure in inducing adequate hypertrophy of the FLR before major hepatic resection for hilar cholangiocarcinoma with obstructive jaundice which had been relieved by percutaneous transhepatic biliary drainage.
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Neoplasias dos Ductos Biliares/terapia , Embolização Terapêutica/métodos , Ducto Hepático Comum , Tumor de Klatskin/terapia , Veia Porta , Distribuição de Qui-Quadrado , Terapia Combinada , Feminino , Hepatectomia/métodos , Humanos , Testes de Função Hepática , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Resultado do TratamentoRESUMO
In this paper the effect of petroleum sulfoxide-carbon tetrachloride used as extractant on the extraction behaviour of molybdenum (V) thiocyanate complex at different concentration of dimethyl sulfoxide and water system is studied by spectrophotometry. The mixture ratio of extraction is directly calculated using spectrophotometric data. Functional relation of mixture ratio and concentration of thiocyanate in mixed solution is discussed. By increasing the percent of volume of dimethyl sulfoxide in mixed solution, the effects of mixture ratio and percentage of extraction were studied. The experimental results were explained. It shows that the extraction system of MoO (SCN)3 has an application value.
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Quelantes/química , Dimetil Sulfóxido/química , Molibdênio/química , Tiocianatos/química , Soluções , Espectrofotometria/métodosRESUMO
Forkhead box M1 (FOXM1), a member of the Fox family of transcriptional factors, is considered to be an independent predictor of poor survival in many solid cancers. However, the underlying mechanism is not yet clear. The aim of the present study was to investigate the clinical significance of the correlation between FOXM1 and epithelial-mesenchymal transition (EMT) in non-small cell lung carcinoma and the possible mechanism responsible for FOXM1-induced EMT and metastasis. In the present study, expression levels of FOXM1 and EMT indicator proteins were determined by tissue microarray (TMA) and immunohistochemical staining, western blotting and reverse transcription-PCR (RT-PCR). Other cellular and molecular approaches including gene transfection, small interfering RNA (siRNA), and migration and invasion assays were utilized. Our results demonstrated that FOXM1 overexpression was statistically significantly associated with a higher TNM stage (p=0.036), lymph node metastasis (p=0.009) and a positive smoking history of the patients (p=0.044). Additionally, high expression of FOXM1 correlated with loss of E-cadherin expression (p<0.001) and anomalous immunopositivity of Vimentin (p=0.002). Moreover, patient survival analysis demonstrated that high expression of FOXM1 (p=0.043) and the presence of lymph node metastasis (p=0.042) were independent prognostic factors for non-small cell lung cancer (NSCLC). Furthermore, various in vitro experiments indicated that overexpression or knockdown of FOXM1 expression altered EMT through activation or inhibition of the AKT/p70S6K signaling pathway. Collectively, the results suggest that FOXM1 may be used as a prognostic indicator for patients with NSCLC and promotes metastasis by inducing EMT of lung cancer cells through activation of the AKT/p70S6K pathway. Therefore, we suggest that FOXM1 may be a potential target for lung cancer therapy.
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Carcinoma Pulmonar de Células não Pequenas/genética , Fatores de Transcrição Forkhead/biossíntese , Metástase Linfática/genética , Prognóstico , Idoso , Carcinoma Pulmonar de Células não Pequenas/patologia , Transição Epitelial-Mesenquimal/genética , Feminino , Proteína Forkhead Box M1 , Fatores de Transcrição Forkhead/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Metástase Linfática/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Proteína Oncogênica v-akt/genética , Proteína Oncogênica v-akt/metabolismo , Proteínas Quinases S6 Ribossômicas 70-kDa/metabolismo , Transdução de Sinais/genéticaRESUMO
AIM:To investigate the expression of perforin and fas-ligand (fas-L) of tumor infiltrating lymphocytes (TILs) in human hepatocellular carcinoma (HCC).METHODS:By in situ hybridization and immunohistochemistry, the perforin and fas-L gene expression of TILs was studied in 20 HCC cases.RESULTS: Positive expression of perforin and fas-L genes was detected in 16 HCC cases. One patient had expression of perforin and fas-L genes in the majority of TILs and survived 1.5 years after tumor resection without HCC relapse.This seems that the presence of a large number of activated T cells might be beneficial for the antitumor immunity. In other cases, less than 10% of TILs were able to express perforin and fas-L genes.CONCLUSION:Although there were a number of T cells in HCC, only few of them were immunoactive and able to kill tumor cells. It seems important to promote further proliferation of these activated T cells in vitro or in vivo.