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1.
J Natl Compr Canc Netw ; 22(2)2024 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-38364363

RESUMO

More than 90 distinct fusion partners of ALK rearrangement have been identified. Different ALK fusions may exhibit different sensitivities to ALK tyrosine kinase inhibitors. The emergence of rare fusions poses significant challenges to targeted therapies. This study aimed to investigate the response of KANK1::ALK fusion to alectinib in an advanced lung adenocarcinoma. A novel KANK1::ALK fusion was identified by next-generation sequencing (NGS) and Ventana immunohistochemistry assessments. A 73-year-old woman who had never smoked was admitted with hemoptysis in May 2020. PET/CT revealed a nodule in the left upper lobe, with bilateral pulmonary and multiple lymph node metastases. The upper lobe nodule of the left lung was diagnosed as adenocarcinoma through bronchofiberscopy biopsy, resulting in a clinical diagnosis of stage IVA (cT1c,N3,M1a). Because the biopsy tissue was insufficient for NGS analysis, a blood-based genetic analysis was performed, revealing the presence of KRAS p.Q61R mutations. The patient received carboplatin and pemetrexed with pembrolizumab as first-line therapy, followed by maintenance therapy of pembrolizumab monotherapy. Although the tumor initially showed significant shrinkage, it unfortunately progressed further after 11 months. Subsequently, the patient was given carboplatin and pemetrexed with pembrolizumab again, but the tumor progression continued. An NGS using a rebiopsy of the left upper lobe tumor suggested a KANK1::ALK fusion. Alectinib was prescribed in January 2022, and a durable partial response was observed after 18 months. ALK rearrangements were observed in the broader spectrum of lung cancers. This study provided a potential treatment option for patients with KANK1::ALK fusions. Further studies are needed to understand the function of these fusions.


Assuntos
Adenocarcinoma de Pulmão , Carbazóis , Neoplasias Pulmonares , Piperidinas , Feminino , Humanos , Idoso , Pemetrexede , Carboplatina/uso terapêutico , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Quinase do Linfoma Anaplásico/genética , Inibidores de Proteínas Quinases/uso terapêutico , Adenocarcinoma de Pulmão/tratamento farmacológico , Adenocarcinoma de Pulmão/genética , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Proteínas do Citoesqueleto/uso terapêutico , Proteínas Adaptadoras de Transdução de Sinal/uso terapêutico
2.
BMC Genomics ; 24(1): 121, 2023 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-36927412

RESUMO

BACKGROUND: Egg quality is a major concern in fish reproduction and development. An effective evaluation of egg quality prior to fertilization is helpful in improving the fertilization rate and survival rate of the larva. In this study, we aim to identify quality instructors from the combination study of fertilization rate, hatching rate, embryo malformation rate and gene expression profile. RESULTS: Eggs from 25 female fish were fertilized with sperm from the same fish. The egg quality was determined by the fertilization rates, hatching rate and embryo malformation rate and divided into three categories, low-quality (< 35%), medium-quality (35 to 75%), and high-quality (> 75%). Due to the distinct difference in fertilization, hatching and embryo malformation rate between low-quality eggs and high-quality eggs, these two groups were considered for the identification of quality markers. Then RNA-seq was performed for the originally preserved eggs from the low-quality group and high-quality group. We profiled the differentially expressed genes and identified a group of RNA-binding proteins (RBPs) as potential regulators. Gene function analysis indicated that most of these genes were enriched in RNA-regulated pathways including RNA processing. The RBPs were more related to egg quality from the PLS-DA analysis. Finally, gene expression was validated by qRT-PCR. CONCLUSIONS: We found a cluster of RBP genes including igf2bp3, zar1, elavl1, rbm25b and related regulatory factors including yy1, sirt1, anp32e, btg4 as novel biomarkers of egg quality.


Assuntos
Peixes-Gato , Animais , Feminino , Masculino , Sêmen , Reprodução , Fertilização , Biomarcadores , Proteínas de Ligação a RNA/genética , Óvulo
3.
Ann Surg Oncol ; 30(6): 3760-3768, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36897416

RESUMO

BACKGROUND: An increasing body of evidence supports the noninferiority of sublobar resection compared with lobectomy in terms of survival for patients with early-stage lung cancer with ground-glass opacities (GGOs). However, few studies have focused on the incidence of lymph node (LN) metastases in these patients. We aimed to analyze N1 and N2 lymph node involvement in patients with non-small cell lung cancer (NSCLC) with GGO components stratified with different consolidation tumor ratio (CTR). PATIENTS AND METHODS: We performed two-center studies by retrospectively reviewing a total of 864 patients with NSCLC with semisolid or pure GGO manifestation (diameter ≤ 3 cm). Clinicopathologic features and outcomes were analyzed. We also reviewed 35 studies to characterize the patient with NSCLC population with the GGO manifestation. RESULTS: In both cohorts, there was no LN involvement for pure GGO NSCLC, while solid predominant GGO exhibited a relatively high LN involvement rate. On the basis of a pooled literature analysis, the incidence of pathologic mediastinal LN was 0% and 3.8% for pure and semisolid GGOs, respectively. GGO NSCLCs with CTR ≤ 0.5 also had rare LN involvement (0.1%). CONCLUSIONS: From two cohorts and pooled literature analysis, LN involvement was not observed in patients with pure GGO, and very few patients with semisolid GGO NSCLC with CTR ≤ 0.5 had LN involvement, revealing that it may be unnecessary to perform lymphadenectomy for pure GGOs, while mediastinal lymph node sampling (MLNS) is enough for semisolid GGOs with CTR ≤ 0.5. For the patients with GGO CTR > 0.5, mediastinal lymphadenectomy (MLD) or MLNS should be considered.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/cirurgia , Estudos Retrospectivos , Metástase Linfática , Prognóstico , Tomografia Computadorizada por Raios X
4.
Ann Surg ; 276(6): e991-e999, 2022 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-33196487

RESUMO

OBJECTIVE: This study aimed to determine the optimal surgical procedure for early-stage pulmonary carcinoids (PCs). BACKGROUND: PCs, comprising typical carcinoids (TCs) and atypical carcinoids (ACs), are rare low-grade malignant tumors. We determine the optimal surgical management for early-stage PCs using data from the Surveillance, Epidemiology, and End Results registry. METHODS: Clinical and survival data of patients with early-stage PC tumors with a diameter ≤3 cm were retrieved. The Kaplan-Meier method and logrank tests were used to assess the differences in overall survival (OS). Subgroup analyses were also performed. To reduce the inherent bias of retrospective studies, two propensity score matching (PSM) analysis with (PSM2) or without (PSM1) consideration of lymph node assessment were performed. RESULTS: In total, 2934 patients with PCs, including 2741 (93.42%) with TCs and 193 (6.58%) with ACs, were recruited. After PSM1 analysis, TC patients in the lobectomy group had a significantly better OS than those in the sublobar resection group ( P = 0.0067), which is more remarkable for patients with a tumor diameter of 2 cm

Assuntos
Tumor Carcinoide , Carcinoma Neuroendócrino , Neoplasias Pulmonares , Humanos , Feminino , Pneumonectomia/métodos , Estudos Retrospectivos , Estadiamento de Neoplasias , Tumor Carcinoide/cirurgia , Tumor Carcinoide/patologia , Carcinoma Neuroendócrino/patologia
5.
Biochem Genet ; 60(6): 2155-2170, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35279761

RESUMO

Breast cancer (BC) is a common malignant tumor, and circular RNA-trefoil factor 1 (circ-TFF1; hsa_circ_0061825) has been found to be highly expressed in BC tissues and cells and is associated with the poor prognosis of BC patients. However, the interaction between circ-TFF1 and microRNA in BC has not been studied. Quantitative real-time PCR was used to detect the expression of circ-TFF1, miR-129-2-3p, and interleukin (IL)-1 receptor-associated kinase 1 (IRAK1). Through the detection of cell proliferation, migration, invasion, tube formation, and apoptosis, cell function was assessed. The expression levels of angiogenesis-related proteins were detected by western blot. The interaction between miR-129-2-3p and circ-TFF1 or IRAK1 was verified by dual-luciferase reporter assay and RNA immunoprecipitation assay. Xenotransplantation experiments were used to confirm the function of circ-TFF1 in vivo. Circ-TFF1 and IRAK1 were significantly high expressed in BC tissues and cells. Silencing of circ-TFF1 reduced the proliferation, migration, invasion and tube formation, while increased the apoptosis of MDA-MB-361 and SK-Br-3 cells. MiR-129-2-3p was a target of circ-TFF1. Silencing of circ-TFF1 inhibited the malignant behavior of BC cells by releasing miR-129-2-3p. In addition, IRAK1 was a target of miR-129-2-3p. Overexpression of IRAK1 partially restored the inhibitory effect of miR-129-2-3p on cell progression. Animal experiments confirmed the anti-tumor effect of circ-TFF1 knockdown in vivo. Circ-TFF1 regulated the expression of IRAK1 by sponging miR-129-2-3p, thereby, promoting the development of BC. These data provided a novel targeted therapy for BC.


Assuntos
MicroRNAs , Neoplasias , Animais , Fator Trefoil-1/genética , Regulação Neoplásica da Expressão Gênica , Movimento Celular/genética , MicroRNAs/genética , Proliferação de Células/genética , Neoplasias/genética , Linhagem Celular Tumoral
6.
J Prosthet Dent ; 127(6): 918-924, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33483139

RESUMO

STATEMENT OF PROBLEM: A silicon carbide (SiC) protective coating has been developed for dental ceramics, but whether the coated ceramics can match the classical VITA shades is unclear. PURPOSE: The purpose of this observational in vitro study was to evaluate the color adaptability of SiC-coated dental ceramics by testing the hypotheses that SiC-coated disks can be fabricated to match standard tooth shades and have a perceptible color match rate of at least 50% for disks with a color difference (ΔE)<2.0. The effects of ΔE, shade hue, shade value, observer sex, years of experience, profession, and shade guide orientation on color perception were studied. MATERIAL AND METHODS: SiC-coated disks were fabricated to color match (ΔEab<3.3) all 16 VITA classical shades. Uncoated disks of each VITA shade were used as the reference materials to determine whether the SiC-coated disks were color matched to the classical VITA shade guide. Three ΔE formulas (76, 94, and 2000) were applied and compared. Participants (N=120) with an average of 22 years of experience included dental school students, dental faculty members, and dental assistants. Pseudoisochromatic plate and the Farnsworth D-15 Panel test for assessing color deficiency and color blindness were administered. Participants then attempted to match SiC-coated disks to standard shade guides arranged by value or hue. All spectrophotometer readings and color matching were conducted in a light booth with standardized daylight illumination. Statistical analysis used the Fisher's exact test to determine factors associated with improved matching performance (α=.05). RESULTS: A significant difference in color match rate was found between disks with ΔE<2.0 (63.9%) and ΔE≥2.0 (41.7%) (P<.001). Arranging shade by value (72.2%) instead of hue (67.2%) produced better color matching (P<.001). Sex (P=.430), profession (P=.708), and years of experience (P=.902) had no significant influence on color matching. CONCLUSIONS: SiC-coated disks were successfully fabricated to match all VITA classical shades, and clinical visual color matching results confirmed that ΔE was a useful metric in optimizing color matching for the SiC-coated dental ceramics.


Assuntos
Planejamento de Prótese Dentária , Pigmentação em Prótese , Compostos Inorgânicos de Carbono , Cerâmica/uso terapêutico , Cor , Percepção de Cores , Humanos , Compostos de Silício
7.
Small ; 17(20): e2100640, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33817985

RESUMO

Neuromorphic systems, which emulate neural functionalities of a human brain, are considered to be an attractive next-generation computing approach, with advantages of high energy efficiency and fast computing speed. After these neuromorphic systems are proposed, it is demonstrated that artificial synapses and neurons can mimic neural functions of biological synapses and neurons. However, since the neuromorphic functionalities are highly related to the surface properties of materials, bulk material-based neuromorphic devices suffer from uncontrollable defects at surfaces and strong scattering caused by dangling bonds. Therefore, 2D materials which have dangling-bond-free surfaces and excellent crystallinity have emerged as promising candidates for neuromorphic computing hardware. First, the fundamental synaptic behavior is reviewed, such as synaptic plasticity and learning rule, and requirements of artificial synapses to emulate biological synapses. In addition, an overview of recent advances on 2D materials-based synaptic devices is summarized by categorizing these into various working principles of artificial synapses. Second, the compulsory behavior and requirements of artificial neurons such as the all-or-nothing law and refractory periods to simulate a spike neural network are described, and the implementation of 2D materials-based artificial neurons to date is reviewed. Finally, future challenges and outlooks of 2D materials-based neuromorphic devices are discussed.


Assuntos
Redes Neurais de Computação , Neurônios , Sinapses , Plasticidade Neuronal
8.
Analyst ; 145(2): 636-642, 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31789325

RESUMO

A novel turn-on fluorescent probe with barbituric acid as a unique recognition group has been rationally designed and synthesized using a facile method for detecting hydrazine. The 5-((7-(dimethylamino)-4,5-dihydronaphtho [1,2-b] thiophen-2-yl)methylene)pyrimidine-2,4,6 (1H,3H,5H)-trione (DPT) probe displays a large emission signal ratio variation (more than a 40-fold enhancement) in the presence of hydrazine under neutral conditions. Interestingly, a novel recognition mechanism based on a hydrazine-triggered addition-cyclisation-retro aldol was proposed and confirmed. Additionally, the DPT probe exhibits a low detection limit (5 × 10-8 M), applicable to the physiological pH range (3-12), a broad linear response range for hydrazine concentrations between 0 and 34 µM and a large Stokes shift (147 nm) for hydrazine detection in aqueous solution. Moreover, the DPT probe was successfully implemented for hydrazine imaging in vivo.

9.
Fish Shellfish Immunol ; 100: 98-108, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32142873

RESUMO

Fish mucus acts as a physiological and immunological barrier for maintaining normal fish physiology and conferring defense against pathogens infection. Here we report proteomic profiling of skin mucus of yellow catfish before and after E. ictaluri infection by Label-free LC-MS/MS approach. A total of 918 non-redundant proteins were identified from 54443 spectra referring to yellow catfish genome database. Further annotation via GO and KEGG database revealed complex protein composition of yellow catfish mucus. Besides structural proteins in mucus, a lot of immune-related proteins were retrieved, such as lectins, complement components, antibacterial peptides and immunoglobins. 133 differentially-expressed proteins (DEPs), including 76 up-regulated and 57 down-regulated proteins, were identified, most of which were enriched into 17 pathways centering on "immune system" category with 33 proteins involved. Consistently, significant proliferation of mucus-secreting goblet cells and CYPA-expressing cells were observed along outside of yellow catfish skin after E. ictaluri infection, indicating an enhanced immune response to E. ictaluri infection in yellow catfish skin mucus. The proteomic data provide systematic protein information to comprehensively understand the biological function of yellow catfish skin mucus in response to bacterial infection.


Assuntos
Peixes-Gato/genética , Infecções por Enterobacteriaceae/veterinária , Proteínas de Peixes/genética , Muco/imunologia , Pele/imunologia , Animais , Peixes-Gato/imunologia , Cromatografia Líquida , Edwardsiella ictaluri , Infecções por Enterobacteriaceae/imunologia , Doenças dos Peixes/imunologia , Perfilação da Expressão Gênica , Masculino , Muco/microbiologia , Proteoma , Pele/microbiologia , Espectrometria de Massas em Tandem
10.
J Am Ceram Soc ; 102(11): 6591-6599, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31819280

RESUMO

SiO2/SiC coatings were deposited onto ceramics disks using plasma enhanced chemical vapor deposition. The effects of deposition pressure and gas-flow ratio on the refractive index, extinction coefficient, and SiC composition were studied. For the highest studied SiH4 to CH4 gas-flow ratio of 1.5, the refractive index increased by 17% from 2.53 (at the wavelength of 845 nm) to 2.96 (at the wavelength of 400 nm). For the lowest studied SiH4 to CH4 gas-flow ratio of 0.5, the refractive index only increased by 4% from 2.11 (at the wavelength of 845 nm) to 2.20 (at the wavelength of 400 nm). At higher deposition pressures, the variation in refractive index of the SiC coatings was significantly lower showing a slight increase from 1.93 (at a wavelength of 845 nm) to 1.96 at a wavelength of 400 nm. Except for the case of a low SiH4 to CH4 gas-flow ratio of 0.5, for light with wavelengths ≤ 650 nm, the extinction coefficient of the SiC coatings increased significantly. Light with a wavelength > 650 nm had an extinction coefficient near 0 in all cases. After annealing the sample at 400°C for 4 hours, hydrogen-related bonds broke and the stress of the film was reduced from -245 to -71 MPa. By utilizing different thicknesses of SiC, the full standard dental shade guide was matched with the ΔE of each coated disk being less than 3.3 compared to the shade guide.

11.
J Oral Rehabil ; 46(6): 503-510, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30759313

RESUMO

OBJECTIVES: The aims of this study were to test the hypotheses that (a) a laserscanner used for measuring maximum depth and volume loss will yield the same results as a surface profilometer; (b) the surface roughness will affect the maximum depth and volume loss measured with the laserscanner; (c) analytical results using the laserscanner from multiple operators have no more than 10% inter-rater difference and; (d) replicating samples using either stone or impression material is an accurate method for measuring wear using the laserscanner. MATERIALS AND METHODS: The volume and maximum depth of indentations from fine, medium and rough burs on glass-ceramic disks were measured using two devices, a surface profilometer (Dektak II, Veeco) and a 3D Laserscanner (LAS-20, SD Mechatronik). Replicates of the indentations made from polyvinysiloxane impression material and gypsum were also measured. RESULTS: Comparison of profilometer and laserscanner readings using ceramic disks demonstrated a mean error of 13.61% for depth and 25.32% for volume. Replication errors were minimal (2.6% for impression, 2.5% for stone). Surface profilometer data for volume measurements revealed a difference of 6.1% for impression and 6.5% for stone compared with ceramics. However, when measurements for replicates were compared between laserscanner and surface profilometer, depth had a mean error of 74% for impression and 51% for stone. Volume differences of 78% for impression and 44% for stone were recorded. CONCLUSION: This work demonstrated that the laserscanner was a convenient device for measuring wear but there is a need to validate the accuracy of the measurements.


Assuntos
Cerâmica , Materiais para Moldagem Odontológica , Teste de Materiais , Propriedades de Superfície
12.
World J Surg Oncol ; 16(1): 209, 2018 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-30333040

RESUMO

BACKGROUND: Chondroma is a slowly growing, benign cartilaginous tumor which predominantly occurs in long bones of the hands and feet. Primary mediastinal chondroma is rare, especially with Horner's syndrome. CASE PRESENTATION: We reported the case of a 31-year-old woman with a posterior mediastinum mass associated with Horner's syndrome. After complete dissection of the mass, a pathological diagnosis of the primary mediastinal chondroma was rendered. The patient has shown no local recurrence or distal disease in a 3.5-year follow-up period. CONCLUSIONS: The preoperative diagnosis of chondroma should combine various examinations for comprehensive evaluation. Complete surgical resection should be the first choice of the treatment due to the risk of malignancy.


Assuntos
Condroma/patologia , Síndrome de Horner/patologia , Neoplasias do Mediastino/patologia , Adulto , Condroma/complicações , Condroma/cirurgia , Feminino , Síndrome de Horner/complicações , Síndrome de Horner/cirurgia , Humanos , Neoplasias do Mediastino/complicações , Neoplasias do Mediastino/cirurgia , Prognóstico
13.
Small ; 12(1): 120-34, 2016 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-26523843

RESUMO

Conventional thin-film diffusion barriers consist of 3D bulk films with high chemical and thermal stability. The purpose of the barrier material is to prevent intermixing or penetration from the two materials that encase it. Adhesion to both top and bottom materials is critical to the success of the barrier. Here, the effectiveness of a single atomic layer of graphene as a solid-state diffusion barrier for common metal schemes used in microelectronics is reviewed, and specific examples are discussed. Initial studies of electrical contacts to graphene show a distinct separation in behavior between metallic groups that strongly or weakly bond to it. The two basic classes of metal reactions with graphene are either physisorbed metals, which bond weakly with graphene, or chemisorbed metals, which bond strongly to graphene. For graphene diffusion barrier testing on Si substrates, an effective barrier can be achieved through the formation of a carbide layer with metals that are chemisorbed. For physisorbed metals, the barrier failure mechanism is loss of adhesion at the metal­graphene interface. A graphene layer encased between two metal layers, in certain cases, can increase the binding energy of both films with graphene, however, certain combinations of metal films are detrimental to the bonding with graphene. While the prospects for graphene's future as a solid-state diffusion barrier are positive, there are open questions, and areas for future research are discussed. A better understanding of the mechanisms which influence graphene's ability to be an effective diffusion barrier in microelectronic applications is required, and additional experiments are needed on a broader range of metals, as well as common metal stack contact structures used in microelectronic applications. The role of defects in the graphene is also a key area, since they will probably influence the barrier properties.

14.
Med Sci Monit ; 21: 3825-33, 2015 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-26644185

RESUMO

BACKGROUND Research shows that type 2 diabetes mellitus (T2DM) affects the risk and prognosis of colorectal cancer (CRC). Here, we conducted a retrospective study to investigate whether the clinicopathological features of CRC patients correlate with their blood glucose levels. MATERIAL AND METHODS We enrolled 391 CRC patients hospitalized in our center between 2008 and 2013. Data of their first fasting plasma glucose (FPG) and 2-h postprandial glucose (2hPPG) level after admission, their clinicopathological features, and survival were collected. The correlations between blood glucose level and clinicopathological features were analyzed by Pearson chi-square analysis. Patient survival was analyzed by Kaplan-Meier and Cox-regression analysis. RESULTS There were 116 out of the 391 CRC patients who had high blood glucose level (H-G group, 29.67%), among which 58 (14.83%), 18 (4.60%), and 40 (10.23%) were diabetes mellitus (DM), impaired glucose tolerance (IGT), and impaired fasting glucose (IFG), respectively, while 275 (70.33%) patients had normal glucose level (N-G group). Compared with the N-G group, patients in the H-G group had larger tumor diameters and lower tumor differentiation (p<0.05). A higher ratio of patients in the H-G group also had more advanced TNM staging and more ulcerative CRC gross type (p<0.05). No significant difference was observed in patient overall survival among different glucose groups. No effect of insulin therapy on CRC development and patient survival was observed. CONCLUSIONS Blood glucose level in CRC patients correlates significantly with local tumor malignancy, but no significant effect on distant metastasis and patient overall survival was observed.


Assuntos
Glicemia/metabolismo , Neoplasias Colorretais/patologia , Neoplasias Colorretais/sangue , Neoplasias Colorretais/complicações , Diabetes Mellitus/sangue , Feminino , Teste de Tolerância a Glucose , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Sobrevida
15.
Nano Lett ; 14(1): 183-90, 2014 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-24299042

RESUMO

Nanoscale self-assembly offers a pathway to realize heterogeneous integration of III-V materials on silicon. However, for III-V nanowires directly grown on silicon, dislocation-free single-crystal quality could only be attained below certain critical dimensions. We recently reported a new approach that overcomes this size constraint, demonstrating the growth of single-crystal InGaAs/GaAs and InP nanoneedles with the base diameters exceeding 1 µm. Here, we report distinct optical characteristics of InP nanoneedles which are varied from mostly zincblende, zincblende/wurtzite-mixed, to pure wurtzite crystalline phase. We achieved, for the first time, pure single-crystal wurtzite-phase InP nanoneedles grown on silicon with bandgaps of 80 meV larger than that of zincblende-phase InP. Being able to attain excellent material quality while scaling up in size promises outstanding device performance of these nanoneedles. At room temperature, a high internal quantum efficiency of 25% and optically pumped lasing are demonstrated for single nanoneedle as-grown on silicon substrate. Recombination dynamics proves the excellent surface quality of the InP nanoneedles, which paves the way toward achieving multijunction photovoltaic cells, long-wavelength heterostructure lasers, and advanced photonic integrated circuits.

16.
Nano Lett ; 14(6): 3235-40, 2014 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-24841253

RESUMO

The growth of III-V nanowires on silicon is a promising approach for low-cost, large-scale III-V photovoltaics. However, performances of III-V nanowire solar cells have not yet been as good as their bulk counterparts, as nanostructured light absorbers are fundamentally challenged by enhanced minority carriers surface recombination rates. The resulting nonradiative losses lead to significant reductions in the external spontaneous emission quantum yield, which, in turn, manifest as penalties in the open-circuit voltage. In this work, calibrated photoluminescence measurements are utilized to construct equivalent voltage-current characteristics relating illumination intensities to Fermi level splitting ΔF inside InP microillars. Under 1 sun, we show that splitting can exceed ΔF ∼ 0.90 eV in undoped pillars. This value can be increased to values of ΔF ∼ 0.95 eV by cleaning pillar surfaces in acidic etchants. Pillars with nanotextured surfaces can yield splitting of ΔF ∼ 0.90 eV, even though they exhibit high densities of stacking faults. Finally, by introducing n-dopants, ΔF of 1.07 eV can be achieved due to a wider bandgap energy in n-doped wurzite InP, the higher brightness of doped materials, and the extraordinarily low surface recombination velocity of InP. This is the highest reported value for InP materials grown on a silicon substrate. These results provide further evidence that InP micropillars on silicon could be a promising material for low-cost, large-scale solar cells with high efficiency.

17.
Int J Mol Sci ; 16(2): 3441-51, 2015 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-25658797

RESUMO

A temperature-sensitive matrine-imprinted polymer was prepared in chloroform by free-radical cross-linking copolymerization of methacrylic acid at 60 °C in the presence of ethylene glycol dimethacrylate as the cross-linker, N-isopropyl acrylamide as the temperature-responsive monomer and matrine as the template molecule. Binding experiments and Scatchard analyses revealed that two classes of binding sites were formed on molecular imprinted polymer (MIP) at 50 °C. Additionally, the thermoresponsive MIP was tested for its application as a sorbent material for the selective separation of matrine from Chinese medicinal plant radix Sophorae tonkinensis. It was shown that the thermoresponsive MIP displayed different efficiency in clean-up and enrichments using the SPE protocol at different temperatures.


Assuntos
Alcaloides/química , Impressão Molecular , Polímeros/química , Quinolizinas/química , Sophora/química , Temperatura , Estrutura Molecular , Polímeros/síntese química , Matrinas
18.
Opt Express ; 22 Suppl 3: A812-7, 2014 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-24922388

RESUMO

We demonstrate GaN-based thin light-emitting diodes (LEDs) on flexible polymer and paper substrates covered with chemical vapor deposited graphene as a transparent-conductive layer. Thin LEDs were fabricated by lifting the sapphire substrate off by Excimer laser heating, followed by transfer of the LEDs to the flexible substrates. These substrates were coated with tri-layer graphene by a wet transfer method. Optical and electrical properties of thin laser lift-offed LEDs on the flexible substrates were characterized under both relaxed and strained conditions. The graphene on paper substrates remained conducting when the graphene/paper structure was folded. The high transmittance, low sheet resistance and high failure strain of the graphene make it an ideal candidate as the transparent and conductive layer in flexible optoelectronics.

19.
Sens Actuators B Chem ; 193: 334-339, 2014 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-32288246

RESUMO

AlGaN/GaN high electron mobility transistors (HEMTs) were used to sense the binding between double stranded DNA (dsDNA) and the severe acute respiratory syndrome coronavirus (SARS-CoV) nucleocapsid protein (N protein). The sensing signals were the drain current change of the HEMTs induced by the protein-dsDNA binding. Binding-site models using surface coverage ratios were utilized to analyze the signals from the HEMT-based sensors to extract the dissociation constants and predict the number of binding sites. Two dissociation constants, K D1 = 0.0955 nM, K D2 = 51.23 nM, were obtained by fitting the experimental results into the two-binding-site model. The result shows that this technique is more competitive than isotope-labeling electrophoretic mobility shift assay (EMSA). We demonstrated that AlGaN/GaN HEMTs were highly potential in constructing a semiconductor-based-sensor binding assay to extract the dissociation constants of nucleotide-protein interaction.

20.
Oral Health Prev Dent ; 12(2): 171-81, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24624397

RESUMO

PURPOSE: To examine the socioeconomic and behavioural risk factors for periodontal disease in women of childbearing age and evaluate the extent of public awareness of the association between oral health and pregnancy in China. MATERIALS AND METHODS: Cross-sectional data from 832 women (including 188 pregnant women) from Yuyao, Zhejiang Province were collected using a structured questionnaire. Demographic data were used to measure the participants' socioeconomic status. The questionnaire assessed knowledge and behaviours related to personal oral hygiene and utilisation of dental care services. Data were divided into pregnant and non-pregnant groups for multivariate logistic regression analysis. RESULTS: In total, 88.3% pregnant women and 74.2% non-pregnant women reported periodontal symptoms. Abnormal body mass index (BMI ≤ 18.5, odds ratio, OR = 0.76, 95% CI 0.27-0.97, P = 0.024; BMI ≥ 23.9, OR = 1.83, 95% CI 1.12-3.35, P = 0.035) was significantly associated with self-reported periodontal disease. Minimal mental stress (OR = 0.56, 95% CI 0.43-0.94, P = 0.028), high annual household income (OR = 0.69, 95% CI 0.17-0.82, P = 0.008), advanced oral hygiene aids (OR = 0.33, 95% CI 0.18-0.49, P < 0.001) and knowledge of the link between pregnancy and periodontal disease (OR = 0.57, 95% CI 0.33-0.96, P = 0.016) were associated with decreased incidence of self reported periodontal disease. CONCLUSIONS: A low socioeconomic background was correlated with the high incidence of self-reported periodontal disease among women of childbearing age in China. Education about primary oral health and equitable distribution of dental services might be expected to improve oral health in this specific population.


Assuntos
Higiene Bucal/estatística & dados numéricos , Doenças Periodontais/epidemiologia , Complicações na Gravidez/epidemiologia , Classe Social , Adulto , Índice de Massa Corporal , China/epidemiologia , Estudos Transversais , Assistência Odontológica/estatística & dados numéricos , Escolaridade , Feminino , Comportamentos Relacionados com a Saúde , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Renda/estatística & dados numéricos , Estado Civil/estatística & dados numéricos , Gravidez , Fatores de Risco , Autorrelato , Estresse Psicológico/epidemiologia , Adulto Jovem
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