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1.
Genomics ; 113(2): 782-794, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33516847

RESUMO

Maize (Zea mays L.) is a thermophilic plant and a minor drop in temperature can prolong the maturity period. Plants respond to cold stress through structural and functional modification in cell membranes as well as changes in the photosynthesis and energy metabolism. In order to understand the molecular mechanisms underlying cold tolerance and adaptation, we employed leaf transcriptome sequencing together with leaf microstructure and relative electrical conductivity measurements in two maize inbred lines, having different cold stress tolerance potentials. The leaf physiological and transcriptomic responses of maize seedlings were studied after growing both inbred lines at 5 °C for 0, 12 and 24 h. Differentially expressed genes were enriched in photosynthesis antenna proteins, MAPK signaling pathway, plant hormone signal transduction, circadian rhythm, secondary metabolites related pathways, ribosome, and proteasome. The seedlings of both genotypes employed common stress responsive pathways to respond to cold stress. However, the cold tolerant line B144 protected its photosystem II from photooxidation by upregulating D1 proteins. The sensitive line Q319 was unable to close its stomata. Collectively, B144 exhibited a cold tolerance owing to its ability to mediate changes in stomata opening as well as protecting photosystem. These results increase our understanding on the cold stress tolerance in maize seedlings and propose multiple key regulators of stress responses such as modifications in photosystem II, stomata guard cell opening and closing, changes in secondary metabolite biosynthesis, and circadian rhythm. This study also presents the signal transduction related changes in MAPK and phytohormone signaling pathways in response to cold stress during seedling stage of maize.

2.
Postgrad Med ; : 1-7, 2020 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-33131368

RESUMO

Objective: The current study was to evaluate the association of Lipoprotein (a) [Lp(a)] and in-hospital outcomes in patients with acute coronary syndrome (ACS) undergoing percutaneous coronary intervention (PCI). Methods: ACS patients undergoing PCI were retrospectively enrolled. Based on Lp(a) level, patients were divided into low (<30 mg/dL) and high (≥30 mg/dL) Lp(a) groups. Results: Compared to those with low Lp(a), patients with high Lp(a) had larger numbers of coronary arteries ≥70% stenosis and had longer coronary artery lesion (P < 0.05). After adjustment for covariates, high Lp(a) remained associated with higher odds of having coronary artery ≥70% stenosis, type C coronary lesion and pre-PCI TIMI flow grade 1/0. Patients with high Lp(a) had a higher unadjusted odds of acute stent thrombosis (odds ratio [OR] 1.10 and 95% confidence interval [CI] 1.01-2.27), congestive heart failure (OR 1.24 and 95% CI 1.15-2.38) and composite in-hospital outcomes (OR 1.28 and 95% CI 1.18-2.42). After adjustment for covariates, patients with high Lp(a) still had a higher odds of congestive heart failure (OR 1.08 and 95% CI 1.01-1.78) and composite in-hospital outcomes (OR 1.12 and 95% CI 1.04-1.81). Conclusion: In ACS patients undergoing PCI, compared to those with low Lp(a), patients with high Lp(a) had more severe coronary artery lesion, higher risk of congestive heart failure and composite in-hospital outcomes.

3.
J Orthop Surg Res ; 15(1): 475, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-33059717

RESUMO

BACKGROUND: Growing evidence indicates that homocysteine is a noteworthy marker for general health status. However, research regarding plasma total homocysteine (tHcy) levels and bone mineral density (BMD) is sparse and controversial. Hence, we aimed to investigate the association between plasma tHcy level within normal range and lumbar BMD in adults. METHODS: In this cross-sectional study, using the National Health and Nutrition Examination Survey database, data on 10748 adults aged between 30 and 85 years were analyzed. The weighted multiple logistic regression analyses were conducted to evaluate the association between plasma tHcy level and lumbar BMD. The fitted smoothing curves were performed to explore potential non-linear relationships. When non-linearity was detected, we further calculated the inflection point using a recursive algorithm and constructed a weighted two-piecewise linear regression model. RESULTS: After adjusting for all the covariates, the association between plasma tHcy and lumbar BMD was different in various age groups (adults aged 30-49 years: ß = -0.0004, 95% CI -0.0025, 0.0018; adults aged 50-69 years: ß = 0.0001, 95% CI -0.0025, 0.0026; adults aged 70-85 years: ß = 0.0050, 95% CI 0.0008, 0.0092). In the subgroup analysis stratified by gender, this association also differed based on gender. There was a negative trend in females (aged 30-49 years: ß = -0.0022, 95% CI -0.0054, 0.0011; aged 50-69 years: ß = -0.0028, 95% CI -0.0062, 0.0007), and a positive trend in males (aged 30-49 years: ß = 0.0018, 95% CI -0.0012, 0.0048; aged 50-69 years: ß = 0.0027, 95% CI -0.0009, 0.0063) in both 30-49 years group and 50-69 years group. In the 70-85 years group, this association was significantly positive in males (ß = 0.0136, 95% CI 0.0068, 0.0204), but was not significantly different in females (ß = 0.0007, 95% CI -0.0046, 0.0060). CONCLUSION: The correlation between plasma tHcy level within the normal range and lumbar BMD differs by age and gender.

4.
Nano Lett ; 20(9): 6824-6830, 2020 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-32816495

RESUMO

Light-emitting diodes (LEDs) based on III-V/II-VI materials have delivered a compelling performance in the mid-infrared (mid-IR) region, which enabled wide-ranging applications in sensing, including environmental monitoring, defense, and medical diagnostics. Continued efforts are underway to realize on-chip sensors via heterogeneous integration of mid-IR emitters on a silicon photonic chip, but the uptake of such an approach is limited by the high costs and interfacial strains, associated with the processes of heterogeneous integrations. Here, the black phosphorus (BP)-based van der Waals (vdW) heterostructures are exploited as room-temperature LEDs. The demonstrated devices emit linearly polarized light, and the spectra cover the technologically important mid-IR atmospheric window. Additionally, the BP LEDs exhibit fast modulation speed and exceptional operation stability. The measured peak extrinsic quantum efficiency is comparable to the III-V/II-VI mid-IR LEDs. By leveraging the integrability of vdW heterostructures, we further demonstrate a silicon photonic waveguide-integrated BP LED.

5.
Sensors (Basel) ; 20(15)2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32752215

RESUMO

Collecting multi-channel sensory signals is a feasible way to enhance performance in the diagnosis of mechanical equipment. In this article, a deep learning method combined with feature fusion on multi-channel sensory signals is proposed. First, a deep neural network (DNN) made up of auto-encoders is adopted to adaptively learn representative features from sensory signal and approximate non-linear relation between symptoms and fault modes. Then, Locality Preserving Projection (LPP) is utilized in the fusion of features extracted from multi-channel sensory signals. Finally, a novel diagnostic model based on multiple DNNs (MDNNs) and softmax is constructed with the input of fused deep features. The proposed method is verified in intelligent failure recognition for automobile final drive to evaluate its performance. A set of contrastive analyses of several intelligent models based on the Back-Propagation Neural Network (BPNN), Support Vector Machine (SVM) and the proposed deep architecture with single sensory signal and multi-channel sensory signals is implemented. The proposed deep architecture of feature extraction and feature fusion on multi-channel sensory signals can effectively recognize the fault patterns of final drive with the best diagnostic accuracy of 95.84%. The results confirm that the proposed method is more robust and effective than other comparative methods in the contrastive experiments.

6.
ACS Appl Mater Interfaces ; 12(1): 1201-1209, 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31804794

RESUMO

Black phosphorus (BP), a narrow band gap semiconductor without out-of-plane dangling bonds, has shown promise for broadband and integrable photodetector applications. Simultaneously exhibiting high speed and high-efficiency operation, however, remains a critical challenge for current BP-based photodetectors. Here, we demonstrate a photodetector based on the BP-based van der Waals heterostructures. The developed photodetector enables broadband responses in the visible to mid-infrared range with external quantum efficiency ranging from 20 to 52% at room temperature. These results together with noise measurements indicate that the photodetector can detect light in the picowatt range. Furthermore, the demonstrated BP detector has ultrafast rise (1.8 ns) and fall (1.68 ns) times, and its photoresponse exhibits reproducible switching behavior even under consecutive and rapid light intensity modulations (2100 cycles, 200 MHz), as indicated by the eye-diagram measurement. By leveraging these features, we show our BP heterostructures can be configured as a point-like detector in a scanning confocal microscopy, useful for mid-infrared imaging applications.

7.
Zhongguo Zhen Jiu ; 39(10): 1117-23, 2019 Oct 12.
Artigo em Chinês | MEDLINE | ID: mdl-31621267

RESUMO

Except the complete literature of Maishu: Xiajing, Tianhui medical slips unearthed in Chengdu also include a part of literature document on meridian, which was seriously damaged. Both of them were found in the same box together with Yimashu. The title of the document chapter was not found in the residual medical slips. By investigated the textual content, it was discovered that such medical slips were different from the Mawangdui silk books, i.e. Yinyang Shiyimai Jiujing and Zubi Shiyimai Jiujing, Maishu of Zhangjiashan bamboo slips of Han Dynasty, as well as Maishu: Xiajing in Tianhui medical slips. But, the sentences in description are similar to the sentences of Jingmai in Lingshu (Miraculous Pivot), therefore, this residual slips was named as Jingmai (Meridian) by the collator. In the paper, by the comparison of this residual slip chapter with the unearthed literature document on meridian as well as Jingmai in Lingshu, the origin and evolution of meridian theory of traditional Chinese medicine in the Qin and Han dynasties were explained. By taking it as an example, the construction process of classical theory of traditional Chinese medicine was explored.


Assuntos
Acupuntura/história , Meridianos , Livros , China , História Antiga , Humanos , Medicina Tradicional Chinesa
8.
Front Neurosci ; 13: 285, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31024229

RESUMO

Aim: Brain tumors are among the most fatal cancers worldwide. Diagnosing and manually segmenting tumors are time-consuming clinical tasks, and success strongly depends on the doctor's experience. Automatic quantitative analysis and accurate segmentation of brain tumors are greatly needed for cancer diagnosis. Methods:This paper presents an advanced three-dimensional multimodal segmentation algorithm called nested dilation networks (NDNs). It is inspired by the U-Net architecture, a convolutional neural network (CNN) developed for biomedical image segmentation and is modified to achieve better performance for brain tumor segmentation. Thus, we propose residual blocks nested with dilations (RnD) in the encoding part to enrich the low-level features and use squeeze-and-excitation (SE) blocks in both the encoding and decoding parts to boost significant features. To prove the reliability of the network structure, we compare our results with those of the standard U-Net and its transmutation networks. Different loss functions are considered to cope with class imbalance problems to maximize the brain tumor segmentation results. A cascade training strategy is employed to run NDNs for coarse-to-fine tumor segmentation. This strategy decomposes the multiclass segmentation problem into three binary segmentation problems and trains each task sequentially. Various augmentation techniques are utilized to increase the diversity of the data to avoid overfitting. Results: This approach achieves Dice similarity scores of 0.6652, 0.5880, and 0.6682 for edema, non-enhancing tumors, and enhancing tumors, respectively, in which the Dice loss is used for single-pass training. After cascade training, the Dice similarity scores rise to 0.7043, 0.5889, and 0.7206, respectively. Conclusion: Experiments show that the proposed deep learning algorithm outperforms other U-Net transmutation networks for brain tumor segmentation. Moreover, applying cascade training to NDNs facilitates better performance than other methods. The findings of this study provide considerable insight into the automatic and accurate segmentation of brain tumors.

9.
Nephrology (Carlton) ; 24(10): 1001-1008, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30537427

RESUMO

BACKGROUND: Klotho G-395-A gene polymorphism is associated with several diseases; however, its association with calcium-phosphate metabolism disorders in end-stage renal disease (ESRD) is unknown. METHODS: A total of 137 patients with ESRD and 80 healthy adults (control) were enrolled in the study. Patients with ESRD were divided into three subgroups: haemodialysis (A1, n = 52), peritoneal dialysis (A2, n = 30), and non-dialysis (A3, n = 55). The klotho G-395-A genotype was detected by TaqMan PCR assay, and ELISA was used to detect the soluble klotho protein (sKL) and fibroblast growth factor (FGF23). Intact parathyroid hormone (iPTH) and other related clinical biochemical parameters were also analyzed for all subjects. RESULTS: (i) Three genotypes (GG, GA and AA) of KL G-395A were detected, and a significant difference between the ESRD and control groups was observed, (ii) sKL was inversely associated with FGF23 in each subgroup and phosphate and positively associated with calcium in A1 and A3. FGF23 was positively associated with phosphate and inversely associated with calcium in each subgroup, (iii) a statistical difference in levels of sKL and FGF23 was observed between GG and AA, as well as between GA and AA. The expression of sKL was lowest and the level of FGF23 was highest in AA and (iv). GA + AA genotypes and FGF23 were risk factors and sKL might be protective factor of calcium-phosphate metabolism disorders. CONCLUSION: Soluble klotho protein and FGF23 were associated with the regulation of calcium and phosphate metabolism, and the A allele of the G-395A klotho gene polymorphism could be a risk factor on calcium-phosphate metabolism disorders in patients with ESRD.


Assuntos
Distúrbios do Metabolismo do Cálcio , Cálcio/metabolismo , Fatores de Crescimento de Fibroblastos/sangue , Glucuronidase/genética , Falência Renal Crônica , Fosfatos/metabolismo , Distúrbios do Metabolismo do Fósforo , Adulto , Distúrbios do Metabolismo do Cálcio/diagnóstico , Distúrbios do Metabolismo do Cálcio/genética , Feminino , Glucuronidase/sangue , Humanos , Falência Renal Crônica/genética , Falência Renal Crônica/metabolismo , Falência Renal Crônica/terapia , Masculino , Distúrbios do Metabolismo do Fósforo/diagnóstico , Distúrbios do Metabolismo do Fósforo/genética , Polimorfismo Genético , Terapia de Substituição Renal/métodos
10.
Ren Fail ; 40(1): 634-639, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30396309

RESUMO

OBJECTIVE: M2 Macrophages could improve tubulointerstitial disease in animal models. HIF-1αpromotes macrophage polarization and is involved in tubular injury. The study aims to observe the clinicopathologic significance of M2 macrophage and HIF-1α in tubulointerstitial injury secondary to primary Sjogren's disease. METHODS: Renal tissue samples from patients with tubulointerstitial disease secondary to primary Sjogren's disease (SS, n = 10), chronic tubulointerstitial nephritis secondary to drug (CIN, n = 8) were included in this study. The expression of CD163, CD68 and HIF-1α were examined by immunohistochemistry or immunofluorescence. RESULTS: (1) Renal involvement was the first manifestation in seven of ten (7/10) patients with pSS, including proteinuria, renal dysfunction, renal tubular acidosis and multiple renal stone; and two patient had intractable hypokalemia. (2) There were numerous CD163- positive cells and CD68- positive cells infiltration in tubulointerstitial injury of pSS, especially in patients with hypokalemia. CD163 positive cells and HIF-1αwere mainly expressed in acute tubulointerstitial injury of pSS, which positively correlated to N-acetyl-ß-D-glucosaminidase and ß2-microglobulin. (3) Compared with CIN, patients with pSS had higher serum globulin level, erythrocyte sedimentation rate (ESR) and lower urinary osmotic pressure. (4) During follow-up of one year, six patients with pSS and acute tubular injury acquired improved renal function on therapy of steroid and total glucosides of peony. The remaining four patients with pSS had stable renal function. CONCLUSION: M2 macrophages are involved in acute tubular injury in patients with primary Sjogren's disease. Early intervention can improve renal function of tubulointerstitial injury secondary to primary Sjogren's disease.


Assuntos
Rim/patologia , Macrófagos/citologia , Nefrite Intersticial/metabolismo , Nefrite Intersticial/patologia , Síndrome de Sjogren/complicações , Adulto , Antígenos CD/metabolismo , Antígenos de Diferenciação Mielomonocítica/metabolismo , Doença Crônica , Feminino , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Imuno-Histoquímica , Macrófagos/metabolismo , Masculino , Pessoa de Meia-Idade , Receptores de Superfície Celular/metabolismo , Adulto Jovem
11.
Zhongguo Zhong Yao Za Zhi ; 43(19): 3979-3983, 2018 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-30453726

RESUMO

Among the medical texts excavated in 2012-2013 from the Han Dynasty tomb at Tianhui township in Sichuan province, we found a collection on the treatment of 60 ailments. Under each ailment, we found one or more formulas, for a total of 106 formulas. The authors of this paper compiled and analyzed these texts based on the original bamboo slips and named this collection with the title Methods for Blending Decoctions to Treat 60 Ailments because the content was focused on blending and making medicinal formulas, and also due to the historical connections with the texts the Record of the Court Scribe, "Biography of Bian Que and Cang Gong". For these reasons, this title was determined, where "blending decoctions" mean "blending and harmonizing medicines optimally in preparation for decocting". The Tianhui texts preserve ancient forms of medicinal formulas, including some once believed to be lost, such as "grain decoctions", "fermented alcohol decoctions", and "fiery decoctions". Based on the historical evidence, we can now ascertain that this text is the "Blending Formulas and Making Decoctions" mentioned in the Record of the Court Scribe written by Cang Gong. Moreover, the medical texts, Canon Formulas in Decoction Form (from the book of Han Dynasty) and the Imperial Pharmacy Formulas to Benefit the People in Song Dynasty are both of this genre of medical literature. The Tianhui text is therefore a representative of this genre of literature in the Western and eastern Han, acting as a key link between early medical formula books and later formula books.


Assuntos
Composição de Medicamentos/métodos , Medicamentos de Ervas Chinesas , Medicina Tradicional Chinesa , Registros , China , Etanol , Manuscritos como Assunto
12.
Nano Lett ; 18(11): 6961-6966, 2018 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-30296107

RESUMO

Ultrathin and flat optical lenses are essential for modern optical imaging, spectroscopy, and energy harvesting. Dielectric metasurfaces comprising nanoscale quasi-periodic resonator arrays are promising for such applications, as they can tailor the phase, amplitude, and polarization of light at subwavelength resolution, enabling multifunctional optical elements. To achieve 2π phase coverage, however, most dielectric metalenses need a thickness comparable to the wavelength, requiring the fabrication of high-aspect-ratio scattering elements. We report ultrathin dielectric metalenses made of van der Waals (vdW) materials, leveraging their high refractive indices and the incomplete phase design approach to achieve device thicknesses down to ∼λ/10, operating at infrared and visible wavelengths. These materials have generated strong interest in recent years due to their advantageous optoelectronic properties. Using vdW metalenses, we demonstrate near-diffraction-limited focusing and imaging and exploit their layered nature to transfer the fabricated metalenses onto flexible substrates to show strain-induced tunable focusing. Our work enables further downscaling of optical elements and opportunities for the integration of metasurface optics in ultraminiature optoelectronic systems.

13.
Zhongguo Zhen Jiu ; 38(10): 1073-9, 2018 Oct 12.
Artigo em Chinês | MEDLINE | ID: mdl-30672237

RESUMO

Ci Shu was nominated after the collection of the bamboo slips of medicine unearthed from the tomb of the Han Dynasty in Tiahui county, Chengdu of Sichuan Province. It is the special chapter on the therapeuticmethods of acupuncture, providing the valuable new historical evidences for the study on the inheritance and evolution of acupuncture in TCM. In the paper, using the cross-proof method among the unearthed literature, the inherited literatures and the unearthed relics, the ancient acupuncture techniques at the early Western Han Dynasty were explored. It was discovered that the manipulations of the different needling techniques, such as pulse needling and intermuscular needling, as well as the forms of the needling tools provided the evidences to the Nine Needles recorded in Lingshu (Miraculous Pivot) and the archaeological discovery. There were many acupuncture prescriptions, reflecting the needling methods recorded in Shiji: Canggong Zhuan (Records of the Grand Historian: Biography of CANG Gong) and Suwen: Miuci Lun (Plain Questions: On Contralateral Puncture) as well as Bianque needling chart, the stone portrait of the Han Dynasty. The close combination between the acupuncture needling techniques and the pulse diagnosis indicates the theoretic essence of the meridian medicine at the ancient time.


Assuntos
Terapia por Acupuntura , Acupuntura/história , Meridianos , História Antiga , Medicina Tradicional Chinesa , Registros
14.
Artigo em Inglês | MEDLINE | ID: mdl-28587151

RESUMO

Tick-borne encephalitis (TBE) is one of natural foci diseases transmitted by ticks. Its distribution and transmission are closely related to geographic and environmental factors. Identification of environmental determinates of TBE is of great importance to understanding the general distribution of existing and potential TBE natural foci. Hulunbuir, one of the most severe endemic areas of the disease, is selected as the study area. Statistical analysis, global and local spatial autocorrelation analysis, and regression methods were applied to detect the spatiotemporal characteristics, compare the impact degree of associated factors, and model the risk distribution using the heterogeneity. The statistical analysis of gridded geographic and environmental factors and TBE incidence show that the TBE patients mainly occurred during spring and summer and that there is a significant positive spatial autocorrelation between the distribution of TBE cases and environmental characteristics. The impact degree of these factors on TBE risks has the following descending order: temperature, relative humidity, vegetation coverage, precipitation and topography. A high-risk area with a triangle shape was determined in the central part of Hulunbuir; the low-risk area is located in the two belts next to the outside edge of the central triangle. The TBE risk distribution revealed that the impact of the geographic factors changed depending on the heterogeneity.


Assuntos
Encefalite Transmitida por Carrapatos/epidemiologia , China/epidemiologia , Vírus da Encefalite Transmitidos por Carrapatos , Geografia , Humanos , Umidade , Incidência , Medição de Risco , Estações do Ano , Análise Espacial , Temperatura
15.
Pathol Res Pract ; 213(9): 1215-1220, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28554749

RESUMO

OBJECTIVES: CD163 and CD206, markers of M2 macrophages, possesses anti-inflammatory properties. This study aims to investigate the clinicopathologic significance of M2 macrophages in patients of glomerulonephritis with crescents. METHODS: Renal tissue samples from patients of glomerulonephritis with more than 30% cell or cell-fibrous crescents, including lupus nephritis (LN, n=14), anti-neutrophil cytoplasmic antibody-associated vasculitis (AAV, n=14), IgA nephropathy(IgAN) (n=11), Henoch Schonlein purpura glomerulonephritis(HSPGN)(n=8)were included in this study. The expression of CD163, CD206 and CD68 in renal tissues was detected by immunohistochemistry or immunofluorescence. RESULTS: (1) CD163 was mainly expressed in cell or cell-fibrous crescents, proliferative glomerular lesions and acute tubulointerstitial injury. There were numerous CD163-positive cells in LN and AAV in comparison with IgAN and HSPGN. (2) CD206-positive cells were mainly observed in acute tubulointerstitial injury, and proliferative glomerular lesions, especially in LN. Patients with LN had numerous CD206-positive cells in glomerular than other groups. The number of CD163-positive cells and CD206-positive cells in acute tubulointerstitial lesions of LN and AAV were more than IgAN and HSPGN. (3) Both the number of CD163-positive cells and CD206-positive cells in acute tubulointerstitial lesions negatively correlated to estimated glomerular filtration rate. (4) In LN, activity index (AI) positively correlated with the number of CD206-positive cells and CD163-positive cells. Dual staining showed that CD163-positive cells and CD206-positive cells also expressed CD68. CONCLUSIONS: CD163-positive cells and CD206-positive cells, subpopulation of macrophages, which were involved in the pathogenesis of active crescentic glomerulonephritis, especially in LN and AAV.


Assuntos
Glomerulonefrite/imunologia , Glomerulonefrite/patologia , Macrófagos/imunologia , Adulto , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/imunologia , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/patologia , Antígenos CD/análise , Antígenos de Diferenciação Mielomonocítica/análise , Feminino , Humanos , Lectinas Tipo C/análise , Nefrite Lúpica/imunologia , Nefrite Lúpica/patologia , Masculino , Lectinas de Ligação a Manose/análise , Pessoa de Meia-Idade , Receptores de Superfície Celular/análise , Adulto Jovem
16.
Nano Lett ; 17(1): 200-205, 2017 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-27936763

RESUMO

Developing a nanoscale, integrable, and electrically pumped single mode light source is an essential step toward on-chip optical information technologies and sensors. Here, we demonstrate nanocavity enhanced electroluminescence in van der Waals heterostructures (vdWhs) at room temperature. The vertically assembled light-emitting device uses graphene/boron nitride as top and bottom tunneling contacts and monolayer WSe2 as an active light emitter. By integrating a photonic crystal cavity on top of the vdWh, we observe the electroluminescence is locally enhanced (>4 times) by the nanocavity. The emission at the cavity resonance is single mode and highly linearly polarized (84%) along the cavity mode. By applying voltage pulses, we demonstrate direct modulation of this single mode electroluminescence at a speed of ∼1 MHz, which is faster than most of the planar optoelectronics based on transition metal chalcogenides (TMDCs). Our work shows that cavity integrated vdWhs present a promising nanoscale optoelectronic platform.

17.
ACS Nano ; 10(11): 10275-10282, 2016 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-27786448

RESUMO

This paper describes an evolutionary approach to design flat multiwavelength achromatic lenses based on subwavelength plasmonic nanoparticles. Our lattice evolution algorithm achieved desired optical responses by tuning the arrangement of the phase units on a discrete square lattice. Lattice lenses consisting of a single type of nanoparticle could operate at any wavelength in the visible to near-infrared regime (540-1000 nm) by tailoring the localized surface plasmon resonance. When the unit cells were expanded to anisotropic particle shapes, the planar optics could selectively focus light depending on the polarization of incident light. Finally, the algorithm realized efficient multiobjective optimization and produced achromatic lattice lenses at up to three wavelengths (λ = 600 nm, λ = 785 nm, and λ = 980 nm) using multiple different nanoparticle shapes.

18.
Nat Commun ; 7: 10568, 2016 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-26843149

RESUMO

While metal is the most common conducting constituent element in the fabrication of metamaterials, graphene provides another useful building block, that is, a truly two-dimensional conducting sheet whose conductivity can be controlled by doping. Here we report the experimental realization of a multilayer structure of alternating graphene and Al2O3 layers, a structure similar to the metal-dielectric multilayers commonly used in creating visible wavelength hyperbolic metamaterials. Chemical vapour deposited graphene rather than exfoliated or epitaxial graphene is used, because layer transfer methods are easily applied in fabrication. We employ a method of doping to increase the layer conductivity, and our analysis shows that the doped chemical vapour deposited graphene has good optical properties in the mid-infrared range. We therefore design the metamaterial for mid-infrared operation; our characterization with an infrared ellipsometer demonstrates that the metamaterial experiences an optical topological transition from elliptic to hyperbolic dispersion at a wavelength of 4.5 µm.

19.
Nano Lett ; 16(2): 1064-8, 2016 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-26808093

RESUMO

In a modern wireless communication system, signal amplification is critical for overcoming losses during multiple data transformations/processes and long-distance transmission. Common mode and differential mode are two fundamental amplification mechanisms, and they utilize totally different circuit configurations. In this paper, we report a new type of dual-gate graphene ambipolar device with capability of operating under both common and differential modes to realize signal amplification. The signal goes through two stages of modulation where the phase of signal can be individually modulated to be either in-phase or out-of-phase at two stages by exploiting the ambipolarity of graphene. As a result, both common and differential mode amplifications can be achieved within one single device, which is not possible in the conventional circuit configuration. In addition, a common-mode rejection ratio as high as 80 dB can be achieved, making it possible for low noise circuit application. These results open up new directions of graphene-based ambipolar electronics that greatly simplify the RF circuit complexity and the design of multifunction device operation.

20.
Int J Clin Exp Pathol ; 8(9): 11386-92, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26617864

RESUMO

OBJECTIVE: To investigate the clinicopathological significance of CD206-positive macrophage expression in patients with acute tubulointerstitial disease, including acute tubular necrosis (ATN) and acute interstitial nephritis (AIN). METHODS: Renal tissue samples from patients with ATN (n=10), AIN (n=10), and minimal change disease (MCD, as disease control, n=8) as well as tissue from normal control kidneys (negative control, n=3) were included in this study. The expression of CD206 and CD68 in renal tissues was detected by immunohistochemistry or immunofluorescence. RESULTS: CD206-positive cells accumulated in areas around damaged tubular cells and regenerating tubules. Compared with AIN patients, ATN patients had lower serum albumin, lower proteinuria, lower urinary osmolality and higher plasma hemoglobin, (P=0.002; P=0.01; P<0.001; P=0.002, respectively). CD206-positive cells could also be observed in the tubular basement membrane and tubule lumen. Some CD206-positive cells infiltrated into the tubular cells in patients with AIN. Compared to patients with ATN, patients with AIN had more CD206-positive cells (P=0.005). In the ATN patients, there were more CD206-positive cells in ischemic tissue. CD206-positive cells were negatively correlated with hemoglobin (r=-0.565, P=0.009) and positively correlated with serum albumin (r=0.496, P=0.026), urinary osmolality (r=0.567, P=0.009) and proteinuria (r=0.460, P=0.041). There was no correlation between CD206-positive cells and eGFR. CONCLUSION: CD206-positive macrophages are involved in the pathogenesis of acute tubular necrosis and acute interstitial nephritis.


Assuntos
Necrose Tubular Aguda/patologia , Macrófagos/patologia , Nefrite Intersticial/patologia , Adulto , Feminino , Imunofluorescência , Humanos , Imuno-Histoquímica , Necrose Tubular Aguda/imunologia , Lectinas Tipo C/imunologia , Macrófagos/imunologia , Masculino , Lectinas de Ligação a Manose/imunologia , Pessoa de Meia-Idade , Nefrite Intersticial/imunologia , Receptores de Superfície Celular/imunologia
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