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1.
Nanotechnology ; 32(26)2021 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-33730707

RESUMO

Single hole transport and spin detection is achievable in standard p-type silicon transistors owing to the strong orbital quantization of disorder based quantum dots. Through the use of the well acting as a pseudo-gate, we discover the formation of a double-quantum dot system exhibiting Pauli spin-blockade and investigate the magnetic field dependence of the leakage current. This enables attributes that are key to hole spin state control to be determined, where we calculate a tunnel couplingtcof 57µeV and a short spin-orbit lengthlSOof 250 nm. The demonstrated strong spin-orbit interaction at the interface when using disorder based quantum dots supports electric-field mediated control. These results provide further motivation that a readily scalable platform such as industry standard silicon technology can be used to investigate interactions which are useful for quantum information processing.

2.
Opt Express ; 26(25): 33180-33191, 2018 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-30645474

RESUMO

We propose a new low VπL, fully-crystalline, accumulation modulator design based on a thin horizontal gate oxide slot fin waveguide, on bonded double Silicon-on-Insulator (SOI). A combination of anisotropic wet etching and the mirrored crystal alignment of the top and bottom SOI layers allows us for the first time to selectively pattern the bottom layer from above. Simulations presented herein show a VπL = 0.17Vcm. Fin-waveguides and passive Mach-Zehnder Interferometer (MZI) devices with fin-waveguide phase shifters have been fabricated, with the fin-waveguides having a transmission loss of 5.8dB/mm and a 13.5nm thick internal gate oxide slot.

3.
Nanotechnology ; 29(47): 475201, 2018 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-30191886

RESUMO

Manipulation of carrier densities at the single electron level is inevitable in modern silicon based transistors to ensure reliable circuit operation with sufficiently low threshold-voltage variations. However, previous methods required statistical analysis to identify devices which exhibit random telegraph signals (RTSs), caused by trapping and de-trapping of a single electron. Here, we show that we can deliberately introduce an RTS in a silicon nanowire transistor, with its probability distribution perfectly controlled by a triple gate. A quantum dot (QD) was electrically defined in a silicon nanowire transistor with a triple gate, and an RTS was observed when two barrier gates were negatively biased to form potential barriers, while the entire nanowire channel was weakly inverted by the top gate. We could successfully derive the energy levels in the QD from the quantum mechanical probability distributions and the average lifetimes of RTSs. This study reveals that we can manipulate individual electrons electrically, even at room temperature, and paves the way to use a charged state for quantum technologies in the future.

4.
Exp Ther Med ; 28(4): 376, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39113904

RESUMO

At present, the optimal therapeutic approach for the treatment of platinum-resistant recurrent ovarian cancer remains to be fully elucidated. The present systematic review and network meta-analysis aimed to elucidate the relative efficacy and safety of apatinib, administered either as monotherapy or in conjunction with chemotherapy, compared with chemotherapy alone, for the treatment of platinum-resistant recurrent ovarian cancer. The PubMed, Embase and Wanfang Data electronic databases were searched, where the search spanned from the conception of the databases until April 2023. A quality evaluation was conducted and R software was used for network meta-analysis. Following inclusion and exclusion criteria screening, the present analysis included 17 clinical trials, combining data from 1,228 patients with platinum-resistant recurrent ovarian cancer categorized into the following three treatment cohorts: i) 555 patients who received apatinib plus chemotherapy; ii) 229 patients who received apatinib alone; and iii) 444 patients who underwent conventional chemotherapy. Results of the present study demonstrated that the co-administration of apatinib with either tegiol [odds ratio (OR), 2.54; 95% CI, 1.06-6.11] or etoposide (OR, 2.12; 95% CI, 1.20-3.74) significantly improved the objective response rate (ORR) compared with that following apatinib monotherapy. By contrast, gemcitabine monotherapy resulted in inferior ORR efficacy compared with that following apatinib (OR, 0.47; 95% CI, 0.23-0.95). In addition, combinations of apatinib with etoposide (OR, 1.32; 95% CI, 1.06-1.64) or paclitaxel (OR, 1.52; 95% CI, 1.04-2.23) demonstrated a significantly improved disease control rates (DCR) compared with those following apatinib alone. According to the area under the cumulative ranking analysis, apatinib and paclitaxel in combination was the most efficacious treatment modality in terms of DCR. In terms of safety, the incidence of adverse events, such as hand-foot syndrome [relative risk (RR), 4.23; 95% CI, 1.80-9.95] and hypertension (RR, 4.80; 95% CI, 1.53-15.05), was found to be significantly higher in patients treated with apatinib-containing therapies, compared with those treated with chemotherapy alone. Consequently, the present meta-analysis highlighted the potential of apatinib, particularly in combination with chemotherapy, as a therapeutic strategy for patients with platinum-resistant recurrent ovarian cancer.

5.
Dis Markers ; 2021: 8819934, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33763157

RESUMO

Non-small-cell lung cancer (NSCLC) is one of the most common types of cancer worldwide. Accumulating evidence has suggested that aberrant expression of microRNAs (miRNAs) is involved in the carcinogenesis and progression of NSCLC. The current study is aimed at investigating the clinical significance of serum miR-629 in NSCLC. The expression levels of serum miR-629 in patients with NSCLC, patients with nonmalignant lung diseases, and healthy controls were assessed by real-time quantitative polymerase chain reaction. Our results showed that serum miR-629 levels were significantly upregulated in NSCLC patients compared to the controls. Serum miR-629 exhibited better performance for discriminating NSCLC patients from healthy controls, compared to the traditional biomarkers CYFRA 21-1 and CEA. In addition, a high serum miR-629 level was positively correlated with adverse clinicopathological parameters including lymph node metastasis, differentiation, and clinical stage. Serum miR-629 was dramatically reduced in the NSCLC cases receiving surgical treatment. Moreover, the patients in the high serum miR-629 group suffered poorer overall survival and disease-free survival than those in the low serum miR-629 group. In conclusion, serum miR-629 might serve as a potential prognostic biomarker for NSCLC.


Assuntos
Biomarcadores Tumorais/sangue , Carcinoma Pulmonar de Células não Pequenas/sangue , Neoplasias Pulmonares/sangue , MicroRNAs/genética , Idoso , Biomarcadores Tumorais/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Feminino , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Metástase Linfática , Masculino , MicroRNAs/metabolismo , Pessoa de Meia-Idade , Regulação para Cima
6.
Micromachines (Basel) ; 11(4)2020 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-32272618

RESUMO

This paper demonstrates that the electrical properties of suspended graphene nanomesh (GNM) can be tuned by systematically changing the porosity with helium ion beam milling (HIBM). The porosity of the GNM is well-controlled by defining the pitch of the periodic nanopores. The defective region surrounding the individual nanopores after HIBM, which limits the minimum pitch achievable between nanopores for a certain dose, is investigated and reported. The exponential relationship between the thermal activation energy (EA) and the porosity is found in the GNM devices. Good EA tuneability observed from the GNMs provides a new approach to the transport gap engineering beyond the conventional nanoribbon method.

7.
Micromachines (Basel) ; 11(7)2020 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-32630087

RESUMO

Controlling the heat transport and thermal conductivity through a material is of prime importance for thermoelectric applications. Phononic crystals, which are a nanostructured array of specially designed pores, can suppress heat transportation owing to the phonon wave interference, resulting in bandgap formation in their band structure. To control heat phonon propagation in thermoelectric devices, phononic crystals with a bandgap in the THz regime are desirable. In this study, we carried out simulation on snowflake shaped phononic crystal and obtained several phononic bandgaps in the THz regime, with the highest being at ≈2 THz. The phononic bandgap position and the width of the bandgap were found to be tunable by varying the neck-length of the snowflake structure. A unique bandgap map computed by varying the neck-length continuously provides enormous amounts of information as to the size and position of the phononic bandgap for various pore dimensions. We have also carried out transmission spectrum analysis and found good agreement with the band structure calculations. The pressure map visualized at various frequencies validates the effectiveness of snowflake shaped nano-pores in suppressing the phonons partially or completely, depending on the transmission probabilities.

8.
Sci Rep ; 8(1): 250, 2018 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-29321552

RESUMO

The Random Telegraph Noise (RTN) in an advanced Metal-Oxide-Semiconductor Field-Effect Transistor (MOSFET) is considered to be triggered by just one electron or one hole, and its importance is recognised upon the aggressive scaling. However, the detailed nature of the charge trap remains to be investigated due to the difficulty to find out the exact device, which shows the RTN feature over statistical variations. Here, we show the RTN can be observed from virtually all devices at low temperatures, and provide a methodology to enable a systematic way to identify the bias conditions to observe the RTN. We found that the RTN was observed at the verge of the Coulomb blockade in the stability diagram of a parasitic Single-Hole-Transistor (SHT), and we have successfully identified the locations of the charge traps by measuring the bias dependence of the RTN.

9.
Intern Med ; 55(4): 339-45, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26875957

RESUMO

OBJECTIVE: Pleural effusion is rarely observed in patients with multiple myeloma (MM). Myeloma cell infiltration or invasion to the pleura is very rare. This study aimed to investigate the clinical characteristics of pleural effusion in patients with MM. METHODS: We retrospectively reviewed the medical records of patients diagnosed with pleural effusion, MM, and pleural effusion with MM between 2004 and 2014 at Beijing Jishuitan Hospital. The present study included patients with pleural effusion who underwent cytological, bacteriological, biochemical and other testing. The cytopathology of abnormal pleural effusion cells was not diagnostic, thus flow cytometry was performed. MM was defined using the diagnosis standard of NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) 2014 for MM. RESULTS: This study included 3,480 pleural effusion patients and 319 MM patients. There were 34 patients with both MM and pleural effusion (17 men and 17 women). The average age was 63 years (range, 48-84 years). Pleural effusion with MM was caused by congestive heart disease, chronic renal failure, hypoalbuminemia, pulmonary infarctions, cirrhosis, pulmonary arterial hypertension, parapneumonic effusion, tuberculous pleural effusion, and myelomatous pleural effusion (MPE). The diagnosis of MPE was confirmed by the detection of myeloma cells in the pleural fluid using flow cytometric analyses. There were only 2 MPE cases in our study. The first MPE case was a woman. The first clinical manifestation was pleural effusion, and the diagnosis was non-secretory MM, DSS stage IIIA (Durie-Salmon staging system); ISS stage I (the International Staging System). The second MPE case was a man who was diagnosed with MM IgA-κ, DSS stage IIIA; ISS stage II. CONCLUSION: The detection rate of MPE was very low. MPE tended to present with yellow exudates and the lack of physical and chemical characteristics. Furthermore, patients with MPE exhibited many yellow nodules on the pleura. These nodules were lobulated and had abundant blood supply. The routine pleural effusion pathological examination had low sensitivity. Flow cytometry may be more useful for improving the detection rate of MPE.


Assuntos
Mieloma Múltiplo/complicações , Pleura/patologia , Derrame Pleural Maligno/etiologia , Idoso , Idoso de 80 Anos ou mais , China/epidemiologia , Comorbidade , Exsudatos e Transudatos , Feminino , Citometria de Fluxo , Humanos , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/patologia , Mieloma Múltiplo/terapia , Derrame Pleural Maligno/patologia , Derrame Pleural Maligno/terapia , Prognóstico , Estudos Retrospectivos , Resultado do Tratamento
10.
Sci Rep ; 5: 11514, 2015 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-26175141

RESUMO

The deficiency of Y3Al5O12:Ce (YAG:Ce) luminescence in red component can be compensated by doping Gd(3+), thus lead to it being widely used for packaging warm white light-emitting diode devices. This article presents a systematic study on the photoluminescence properties, crystal structures and electronic band structures of (Y1-xGdx)3Al5O12: Ce(3+) using powerful experimental techniques of thermally stimulated luminescence, X-ray diffraction, X-ray absorption near edge structure (XANES), extended X-ray absorption fine structure (EXAFS) and ultraviolet photoelectron spectra (UPS) of the valence band, assisted with theoretical calculations on the band structure, density of states (DOS), and charge deformation density (CDD). A new interpretation from the viewpoint of compression deformation of electron cloud in a rigid structure by combining orbital hybridization with solid-state energy band theory together is put forward to illustrate the intrinsic mechanisms that cause the emission spectral shift, thermal quenching, and luminescence intensity decrease of YAG: Ce upon substitution of Y(3+) by Gd(3+), which are out of the explanation of the classic configuration coordinate model. The results indicate that in a rigid structure, the charge deformation provides an efficient way to tune chromaticity, but the band gaps and crystal defects must be controlled by comprehensively accounting for luminescence thermal stability and efficiency.

11.
ACS Comb Sci ; 14(12): 636-44, 2012 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-23095104

RESUMO

The best performance of the phosphor Li(2)SrSiO(4): Eu(2+), Ce(3+) in terms of luminescence efficiency (LE), color rendering index (CRI) and color temperature (Tc) for light-emitting diode application was optimized with combinatorial approach. The combinatorial libraries were synthesized with solution-based method and the scale-up samples were synthesized with conventional solid-reaction method. Crystal structure was investigated by using the X-ray diffraction spectrometer. The emission spectra of each sample in combinatorial libraries were measured in situ by using a fiber optic spectrometer. Fluorescence spectrometers were used to record excitation and emission spectra of bulk samples. White light generation was tuned up by tailoring Eu(2+) and Ce(3+) concentrations in the single-phased host of Li(2)SrSiO(4) under near-ultraviolet excitation, but it exhibited low efficiency of luminescence and poor color rendering index. The effects of each level of the Eu(2+) and Ce(3+) concentrations on LE, CRI, and Tc were evaluated with the Taguchi method. The optimum levels of the interaction pairs between Eu(2+) and Ce(3+) concentration on LE, CRI, and Tc were [2, 1] (0.006 M, 0.003 M), [1, 2] (0.003 M, 0.006 M), and [3, 1] (0.009 M, 0.00 3M), respectively. The thermal stability of luminescence, the external quantum efficiency (QE), luminance, chromaticity coordinates, correlated color temperature, color purity including the composition ratio of RGB in white light, and color rendering index of the white light emission of phosphor were evaluated comprehensively from a bulk sample.


Assuntos
Cério/química , Técnicas de Química Combinatória , Európio/química , Silicatos/química , Luminescência , Temperatura
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