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1.
J Thorac Dis ; 16(1): 311-320, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38410566

RESUMO

Background: Chest wall re-depression after bar removal (BR) in pectus excavatum (PE) is insufficiently investigated. However, it is not easy to investigate chest wall re-depression due to its multifactorial characteristics. Herein, we investigated chest wall re-depression after BR using machine learning algorithms. To the best of my knowledge, this is the first study of chest wall re-depression after BR using machine learning algorithms. Methods: We retrospectively reviewed 199 consecutive subjects who underwent both minimally invasive repair of pectus excavatum (MIRPE) and BR at a single hospital from March 2012 to June 2020. We investigated attributes of chest wall re-depression and risk factors for recurrence after BR, predicted final degree and recurrence of PE after BR, and suggested the optimal age at the time of MIRPE based on recurrence. Data for the chest wall re-depression were analyzed to discover differences according to age group [<10 years (early repair group; EG) vs. ≥10 years (late repair group; LG)]. Results: We observed no significant difference between the Haller index and radiographical pectus index (RPI) (P=0.431) and a significant correlation between Haller index and RPI (P<0.001). RPI significantly increased for the first 6 months after BR in both age groups (both P<0.001) and was maintained at 1 year after BR. RPI value of the LG were significantly higher than those of the EG for the entire period after MIRPE (P=0.041). Recurrence of PE in the LG was significantly more frequent than in the EG (P<0.001). RPI values before and after MIRPE and age group were identified as independent risk factors for recurrence after BR (P<0.001, P=0.007, and P=0.001, respectively). The linear regression model outperformed for final RPI with performance scores of mean squared error 0.198, root mean squared error 0.445, mean absolute error 0.336, and R2 0.415. In addition, the logistic regression model outperformed for predicting recurrence with performance scores of 0.865 the area under the curve, 0.884 accuracy, 0.859 F1, 0.865 precision, and 0.884 recall. Conclusions: The present study shows that machine learning algorithms can provide good estimates for postoperative results in PE. An approach integrating machine learning models and readily available clinical data can be used to create other models in the thoracic surgery field.

2.
Phys Rev Lett ; 131(22): 223602, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38101366

RESUMO

Coherent light detection and ranging (LIDAR) offers exceptional sensitivity and precision in measuring the distance of remote objects by employing first-order interference. However, the ranging capability of coherent LIDAR is principally constrained by the coherence time of the light source determined by the spectral bandwidth. Here, we introduce coherent two-photon LIDAR, which eliminates the range limitation of coherent LIDAR due to the coherence time. Our scheme capitalizes on the counterintuitive phenomenon of two-photon interference of thermal light, in which the second-order interference fringe remains impervious to the short coherence time of the light source determined by the spectral bandwidth. By combining this feature with transverse two-photon interference of thermal light, we demonstrate distance ranging beyond the coherence time without relying on time-domain interference fringes. Moreover, we show that our coherent two-photon LIDAR scheme is robust to turbulence and ambient noise. This work opens up novel applications of two-photon correlation in classical light.

3.
Phys Rev Lett ; 129(9): 093601, 2022 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-36083682

RESUMO

The stationary light pulse (SLP) refers to a zero-group-velocity optical pulse in an atomic ensemble prepared by two counterpropagating driving fields. Despite the uniqueness of an optical pulse trapped within an atomic medium without a cavity, observations of SLP so far have been limited to trapping a single optical pulse due to the stringent SLP phase-matching condition, and this has severely hindered the development of SLP-based applications. In this Letter, we first show theoretically that the SLP process in fact supports two phase-matching conditions and we then utilize the result to experimentally demonstrate simultaneous SLP trapping of two optical pulses for the duration from 0.8 to 2.0 µs. The characteristic dissipation time, obtained by the release efficiency measurement from the SLP trapping state, is 1.22 µs, which corresponds to an effective Q factor of 2.9×10^{9}. Our Letter is expected to bring forth interesting SLP-based applications, such as, efficient photon-photon interaction, spatially multimode coherent quantum memory, creation of exotic photonic gas states, etc.

4.
Phys Rev Lett ; 128(4): 040503, 2022 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-35148150

RESUMO

Weak-value amplification (WVA) provides a way for amplified detection of a tiny physical signal at the expense of a lower detection probability. Despite this trade-off, due to its robustness against certain types of noise, WVA has advantages over conventional measurements in precision metrology. Moreover, it has been shown that WVA-based metrology can reach the Heisenberg limit using entangled resources, but preparing macroscopic entangled resources remains challenging. Here, we demonstrate a novel WVA scheme based on iterative interactions, achieving the Heisenberg-limited precision scaling without resorting to entanglement. This indicates that the perceived advantages of the entanglement-assisted WVA are in fact due to iterative interactions between each particle of an entangled system and a meter, rather than coming from the entanglement itself. Our work opens a practical pathway for achieving the Heisenberg-limited WVA without using fragile and experimentally demanding entangled resources.

5.
Opt Express ; 29(2): 2348-2363, 2021 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-33726431

RESUMO

A key technique to perform proper quantum information processing is to get a high visibility quantum interference between independent single photons. One of the crucial elements that affects the quantum interference is a group velocity dispersion that occurs when single photons pass through a dispersive medium. We theoretically and experimentally demonstrate that an effect of group velocity dispersion on the two-photon interference can be cancelled if two independent single photons experience the same amount of pulse broadening. This dispersion cancellation effect can be applied to a multi-path linear interferometer with multiple independent single photons. As multi-path quantum interferometers are at the heart of quantum communication, photonic quantum computing, and boson sampling applications, our work should find wide applicability in quantum information science.

6.
Opt Lett ; 45(24): 6748-6751, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-33325887

RESUMO

It has recently been shown that counter-intuitive Franson-like second-order interference can be observed with a pair of classically correlated pseudo thermal light beams and two separate unbalanced interferometers (UIs): the second-order interference visibility remains fixed at 1/3 even though the path length difference in each UI is increased significantly beyond the coherence length of the pseudo thermal light [Phys. Rev. Lett.119, 223603 (2017)PRLTAO0031-900710.1103/PhysRevLett.119.223603]. However, as the pseudo thermal beam itself originated from a long-coherence laser (and by using a rotating ground disk), there exists the possibility of a classical theoretical model to account for second-order interference beyond the coherence time on the long coherence time of the original laser beam. In this work, we experimentally explore this counter-intuitive phenomenon with a true thermal photon source generated via quantum thermalization, i.e., obtaining a mixed state from a pure two-photon entangled state. This experiment not only demonstrates the unique second-order coherence properties of thermal light clearly but may also open up remote sensing applications based on such effects.

7.
J Clin Med ; 9(10)2020 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-33003602

RESUMO

BACKGROUND AND AIMS: Endoscopic ultrasonography (EUS) is a useful diagnostic modality for evaluating gastric mesenchymal tumors; however, differentiating gastrointestinal stromal tumors (GISTs) from benign mesenchymal tumors such as leiomyomas and schwannomas remains challenging. For this reason, we developed a convolutional neural network computer-aided diagnosis (CNN-CAD) system that can analyze gastric mesenchymal tumors on EUS images. METHODS: A total of 905 EUS images of gastric mesenchymal tumors (pathologically confirmed GIST, leiomyoma, and schwannoma) were used as a training dataset. Validation was performed using 212 EUS images of gastric mesenchymal tumors. This test dataset was interpreted by three experienced and three junior endoscopists. RESULTS: The sensitivity, specificity, and accuracy of the CNN-CAD system for differentiating GISTs from non-GIST tumors were 83.0%, 75.5%, and 79.2%, respectively. Its diagnostic specificity and accuracy were significantly higher than those of two experienced and one junior endoscopists. In the further sequential analysis to differentiate leiomyoma from schwannoma in non-GIST tumors, the final diagnostic accuracy of the CNN-CAD system was 72.5%, which was significantly higher than that of two experienced and one junior endoscopists. CONCLUSIONS: Our CNN-CAD system showed high accuracy in diagnosing gastric mesenchymal tumors on EUS images. It may complement the current clinical practices in the EUS diagnosis of gastric mesenchymal tumors.

8.
Theranostics ; 10(21): 9579-9590, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32863946

RESUMO

The metabolic properties of tumor microenvironment (TME) are dynamically dysregulated to achieve immune escape and promote cancer cell survival. However, in vivo properties of glucose metabolism in cancer and immune cells are poorly understood and their clinical application to development of a biomarker reflecting immune functionality is still lacking. Methods: We analyzed RNA-seq and fluorodeoxyglucose (FDG) positron emission tomography profiles of 63 lung squamous cell carcinoma (LUSC) specimens to correlate FDG uptake, expression of glucose transporters (GLUT) by RNA-seq and immune cell enrichment score (ImmuneScore). Single cell RNA-seq analysis in five lung cancer specimens was performed. We tested the GLUT3/GLUT1 ratio, the GLUT-ratio, as a surrogate representing immune metabolic functionality by investigating the association with immunotherapy response in two melanoma cohorts. Results: ImmuneScore showed a negative correlation with GLUT1 (r = -0.70, p < 0.01) and a positive correlation with GLUT3 (r = 0.39, p < 0.01) in LUSC. Single-cell RNA-seq showed GLUT1 and GLUT3 were mostly expressed in cancer and immune cells, respectively. In immune-poor LUSC, FDG uptake was positively correlated with GLUT1 (r = 0.27, p = 0.04) and negatively correlated with ImmuneScore (r = -0.28, p = 0.04). In immune-rich LUSC, FDG uptake was positively correlated with both GLUT3 (r = 0.78, p = 0.01) and ImmuneScore (r = 0.58, p = 0.10). The GLUT-ratio was higher in anti-PD1 responders than nonresponders (p = 0.08 for baseline; p = 0.02 for on-treatment) and associated with a progression-free survival in melanoma patients who treated with anti-CTLA4 (p = 0.04). Conclusions: Competitive uptake of glucose by cancer and immune cells in TME could be mediated by differential GLUT expression in these cells.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma de Células Escamosas/metabolismo , Proteínas Facilitadoras de Transporte de Glucose/metabolismo , Glucose/metabolismo , Neoplasias Pulmonares/metabolismo , Fluordesoxiglucose F18/metabolismo , Humanos , Imunoterapia/métodos , Tomografia por Emissão de Pósitrons/métodos , Compostos Radiofarmacêuticos/metabolismo , Microambiente Tumoral/imunologia
9.
Phys Rev Lett ; 124(21): 210401, 2020 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-32530676

RESUMO

Recent quantum technologies utilize complex multidimensional processes that govern the dynamics of quantum systems. We develop an adaptive diagonal-element-probing compression technique that feasibly characterizes any unknown quantum processes using much fewer measurements compared to conventional methods. This technique utilizes compressive projective measurements that are generalizable to an arbitrary number of subsystems. Both numerical analysis and experimental results with unitary gates demonstrate low measurement costs, of order O(d^{2}) for d-dimensional systems, and robustness against statistical noise. Our work potentially paves the way for a reliable and highly compressive characterization of general quantum devices.

10.
Wound Manag Prev ; 66(3): 40-47, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32294055

RESUMO

Treating soft tissue defects occurring over the posterior elbow is challenging. PURPOSE: This study aimed to evaluate the long-term outcomes of using rotation flaps for soft tissue defects over the posterior elbow. METHODS: A retrospective study was conducted among patients who had sustained posterior elbow defects and underwent rotation flap under local anesthesia between January 2, 2011, and December 31, 2014. Patient inclusion criteria stipulated the soft tissue defect had to be small (<12 cm2), was the result of wound dehiscence following posterior approach surgery immediately following trauma, and had failed to heal using nonsurgical treatment or primary closure. Patients with an active infection, malignancies, a defect of any etiology other than trauma, or incomplete operative data were excluded. Patient demographics, medical history, operative reports, and outcomes were abstracted. Flap failure and surgical complications were monitored for a minimum of 2 years after surgery. Range of motion (ROM; 0˚ to normal 130˚) and Mayo Elbow Performance Scores (MEPS) were evaluated and recorded before surgery and after 2 years' follow-up and included evaluating pain, ROM, stability, and daily function. Patient, wound, surgical, and wound healing variables were compared between the flap survival and flap failure/complication groups using Mann-Whitney U and chi-squared tests. The Wilcoxon signed-rank test was used to compare pre- and postoperative MEPS and elbow ROM. RESULTS: Thirty (30) patients (13 male, 17 female; mean age 55 ± 15.6 [range 19-74] years) had complete records. Eighteen (18) flaps were created using the transolecranon approach, and 12 rotation flaps involved an olecranon fracture; 24 flaps survived and 6 patients experienced flap failure/complications (wound dehiscence or infection). Mean procedure duration was 25.6 ± 10.1 minutes. All defects were located over the olecranon with exposed bone or hardware. Mean defect size was 7.4 cm2 ± 2.9 cm2, the average defect duration was 60.4 (range 31-89) days, average time to wound healing was 21.9 ± 11.5 days, and mean follow-up time was 29.4 (range 24-56) months. All flaps successfully survived without recurrence. Mean pre- and postoperative MEPS were significantly different (56.4 vs. 90.2 points; P <.001). ROM did not differ significantly between mean preoperative range (extension 9.8˚ ± 3.2˚ and flexion 116.7˚ ± 10.2˚) and mean final follow-up range (extension 9.6˚ ± 2.6˚ and flexion 118.5˚ ± 11.3˚; P = .459). CONCLUSION: Rotation flap surgery performed under local anesthesia may offer a simple and safe option in the treatment of small (<12 cm2) trauma-related defects over the posterior elbow. More research is needed to develop evidence-based guidelines for optimal approaches to posterior elbow soft tissue defect closure techniques.


Assuntos
Cotovelo/cirurgia , Lesões dos Tecidos Moles/cirurgia , Retalhos Cirúrgicos/fisiologia , Adulto , Idoso , Cotovelo/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos de Cirurgia Plástica/métodos , Estudos Retrospectivos , Lesões dos Tecidos Moles/fisiopatologia , Retalhos Cirúrgicos/irrigação sanguínea
11.
Opt Express ; 28(5): 6929-6936, 2020 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-32225930

RESUMO

BosonSampling is a problem of sampling events according to the transition probabilities of indistinguishable photons in a linear optical network. Computational hardness of BosonSampling depends on photon-number statistics of the input light. BosonSampling with multi-photon Fock states at the input is believed to be classically intractable but there exists an efficient classical algorithm for classical input states. In this paper, we present a mathematical connection between BosonSampling with quantum and classical light inputs. Specifically, we show that the generating function of a transition probability for Fock-state BosonSampling (FBS) can be expressed as a transition probability of thermal-light inputs. The closed-form expression of a thermal-light transition probability allows all possible transition probabilities of FBS to be obtained by calculating a single matrix permanent. Moreover, the transition probability of FBS is shown to be expressed as an integral involving a Gaussian function multiplied by a Laguerre polynomial, resulting in a fast oscillating integrand. Our work sheds new light on computational hardness of FBS by identifying the mathematical connection between BosonSampling with quantum and classical light.

12.
Opt Lett ; 45(7): 1802-1805, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32236003

RESUMO

A source of hyper-entangled photons plays a vital role in quantum information processing, owing to its high information capacity. In this Letter, we demonstrate a convenient method to generate polarization and orbital angular momentum (OAM) hyper-entangled photon pairs via spontaneous four-wave mixing (SFWM) in a hot $ ^{87}{\rm Rb} $87Rb atomic vapor. The polarization entanglement is achieved by coherently combining two SFWM paths with the aid of two beam displacers that constitute a phase self-stabilized interferometer, and OAM entanglement is realized by taking advantage of the OAM conservation condition during the SFWM process. Our hyper-entangled biphoton source possesses high brightness and high nonclassicality and may have broad applications in atom-photon-interaction-based quantum networks.

13.
Auris Nasus Larynx ; 47(3): 415-424, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31822346

RESUMO

OBJECTIVE: Particulate matter (PM), which contains organic compounds and toxic metals, is the major cause of air pollution. PM enters the body, causing various health problems. Although the effects of PM on the lower respiratory tract have been extensively investigated, the effects on the upper respiratory tract (including the nasal cavity) require further evaluation. To investigate the effect of fluticasone propionate (FP) on nasal fibroblasts exposed to UPM. METHODS: Samples of inferior turbinate tissue were obtained from six patients. The fibroblasts isolated from these samples were exposed to UPM and/or FP. The expression of interleukin (IL)-6, CXC chemokine ligand (CXCL) 1, IL-1ß, and tumour necrosis factor-alpha (TNF-α) in nasal fibroblasts was analysed using real-time PCR and enzyme-linked immunosorbent assays. The protein levels of nuclear factor kappa B (NF-κB) and signal transducer and activator of transcription 3 (STAT3) were analysed by western blotting. RESULTS: FP reversed the UPM-induced reduction in cell viability. The mRNA and protein levels of IL-6, CXCL1, IL-1ß, and TNF-α were significantly increased by UPM. FP reversed the UPM-induced increases in the protein levels of NF-κB and phosphorylated-STAT3 in a dose-dependent manner. In addition, TNF-α, an inducer of NF-κB, reversed the FP-induced reduction in the levels of signalling molecules. CONCLUSION: UPM induces the expression of IL-6, CXCL1, IL-1ß, and TNF-α in nasal fibroblasts and this effect is reversed by FP via the STAT3 and NF-κB signalling pathways. These results suggest that FP has therapeutic potential for nasal diseases related to UPM, such as allergic and chronic rhinitis.


Assuntos
Citocinas/metabolismo , Fibroblastos/efeitos dos fármacos , Fluticasona/farmacologia , Material Particulado/farmacologia , Adulto , Células Cultivadas , Quimiocina CXCL1/metabolismo , Ensaio de Imunoadsorção Enzimática , Feminino , Fibroblastos/metabolismo , Humanos , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Masculino , Material Particulado/efeitos adversos , Reação em Cadeia da Polimerase em Tempo Real , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais , Fator de Necrose Tumoral alfa/metabolismo
14.
Opt Express ; 27(24): 34611-34617, 2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31878648

RESUMO

Continuous-variable position-momentum entanglement (or Einstein-Podolsky-Rosen entanglement) of two particles has played important roles in the fundamental study of quantum physics as well as in the progress of quantum information. In this paper, we propose a scheme to generate Einstein-Podolsky-Rosen (EPR) position-momentum entangled photon pairs efficiently via spontaneous four-wave mixing (SFWM) process in a hot rubidium gas cell. The EPR entanglement between the photon pair is measured and characterized by using the ghost interference and the ghost imaging method. Due to the simplicity of the experimental setup and the high photon pair generation rate, our EPR entangled photon source may has potential applications in quantum imaging, hyperentanglement preparation and atomic ensemble based quantum information processing and quantum communication protocols.

15.
Phys Rev Lett ; 122(12): 123607, 2019 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-30978083

RESUMO

In quantum communication and photonic quantum information processing, the requirement of quantum repeaters and quantum memory often imposes a strict bandwidth prerequisite for the entangled photons. At the same time, there is ever more increasing demand for entangling more degrees of freedom, i.e., hyperentanglement, for a photon pair. In this Letter, we report the direct generation of narrow-band orbital angular momentum (OAM) and polarization hyperentangled photons from cold atoms. The narrow-band photon pair is naturally entangled in polarization and OAM, in addition to time-frequency, degrees of freedom due to spin and orbital angular momentum conservation conditions in the spontaneous four-wave mixing process in a cold atom ensemble. The narrow-band hyperentangled photon pair source reported here is expected to play important roles in quantum memory-based long-distance quantum communication.

16.
Opt Express ; 27(5): 7593-7601, 2019 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-30876321

RESUMO

It has been known that suitably placed external mirrors can enhance and suppress emission of entangled photon pairs in spontaneous parametric down-conversion (SPDC), known as frustrated two-photon creation via interference. In this work, we report periodic revival of frustrated two-photon creation via interference with SPDC pumped by a continuous-wave (cw) multi-mode laser. As the mirrors are translated relative to the position of the SPDC source, the effect of frustrated two-photon creation via interference gradually dies off. However, as the mirrors are translated even further, the effect of frustrated two-photon creation via interference re-appears periodically. Our theoretical and numerical analyses show that this revival phenomenon is due to the nature of cw multi-mode pump laser. This work clearly demonstrates how the properties of the pump laser, in addition to suitably placed external mirrors, can be used to modify the process of spontaneous two-photon emission.

17.
Gastric Cancer ; 22(5): 980-987, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-30778798

RESUMO

BACKGROUND: When gastric mesenchymal tumors (GMTs) measuring 2-5 cm in size are found, whether to undergo further treatment or not is controversial. Endoscopic ultrasonography (EUS) is useful for the evaluation of malignant potential of GMTs, but has limitations, such as subjective interpretation of EUS images. Therefore, we aimed to develop a scoring system based on the digital image analysis of EUS images to predict gastrointestinal stromal tumors (GISTs). METHODS: We included 103 patients with histopathologically proven GIST, leiomyoma or schwannoma on surgically resected specimen who underwent EUS examination between January 2007 and June 2018. After standardization of the EUS images, brightness values, including the mean (Tmean), indicative of echogenicity, and the standard deviation (TSD), indicative of heterogeneity, in the tumors were analyzed. RESULTS: Age, Tmean, and TSD were significantly higher in GISTs than in non-GISTs. The sensitivity and specificity were almost optimized for differentiating GISTs from non-GISTs when the critical values of age, Tmean, and TSD were 57.5 years, 67.0, and 25.6, respectively. A GIST-predicting scoring system was created by assigning 3 points for Tmean ≥ 67, 2 points for age ≥ 58 years, and 1 point for TSD ≥ 26. When GMTs with 3 points or more were diagnosed as GISTs, the sensitivity, specificity, and accuracy of the scoring system were 86.5%, 75.9%, and 83.5%, respectively. CONCLUSIONS: The scoring system based on the information of digital image analysis is useful in predicting GISTs in case of GMTs that are 2-5 cm in size.


Assuntos
Endossonografia/métodos , Neoplasias Gastrointestinais/patologia , Tumores do Estroma Gastrointestinal/patologia , Processamento de Imagem Assistida por Computador/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Neoplasias Gastrointestinais/diagnóstico por imagem , Neoplasias Gastrointestinais/cirurgia , Tumores do Estroma Gastrointestinal/diagnóstico por imagem , Tumores do Estroma Gastrointestinal/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Curva ROC , Estudos Retrospectivos
18.
Opt Lett ; 44(2): 447-450, 2019 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-30644922

RESUMO

The development of quantum photonic information technology demands high-quality photon sources. Here we demonstrate a low-noise and high-speed photon source generated by the spontaneous four-wave mixing process in a micro/nanofiber (MNF). The pair generation in a MNF is tailorable by controlling its diameter and designed for creating signal and idler photons in the silicon-based detector wavelength range, yielding high detection efficiency and coincidence count rate. This MNF photon source can be coupled to other fiber systems with negligible coupling loss and can be efficiently exploited as fiber-based quantum light sources for quantum information applications.

19.
Nano Lett ; 18(8): 4710-4715, 2018 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-29932664

RESUMO

Single-photon emitters play an essential role in quantum technologies, including quantum computing and quantum communications. Atomic defects in hexagonal boron nitride ( h-BN) have recently emerged as new room-temperature single-photon emitters in solid-state systems, but the development of scalable and tunable h-BN single-photon emitters requires external methods that can control the emission energy of individual defects. Here, by fabricating van der Waals heterostructures of h-BN and graphene, we demonstrate the electrical control of single-photon emission from atomic defects in h-BN via the Stark effect. By applying an out-of-plane electric field through graphene gates, we observed Stark shifts as large as 5.4 nm per GV/m. The Stark shift generated upon a vertical electric field suggests the existence of out-of-plane dipole moments associated with atomic defect emitters, which is supported by first-principles theoretical calculations. Furthermore, we found field-induced discrete modification and stabilization of emission intensity, which were reversibly controllable with an external electric field.

20.
Cancer Immunol Res ; 6(7): 848-859, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29720381

RESUMO

The immune microenvironment in lung squamous cell carcinoma (LUSC) is not well understood, with interactions between the host immune system and the tumor, as well as the molecular pathogenesis of LUSC, awaiting better characterization. To date, no molecularly targeted agents have been developed for LUSC treatment. Identification of predictive and prognostic biomarkers for LUSC could help optimize therapy decisions. We sequenced whole exomes and RNA from 101 tumors and matched noncancer control Korean samples. We used the information to predict subtype-specific interactions within the LUSC microenvironment and to connect genomic alterations with immune signatures. Hierarchical clustering based on gene expression and mutational profiling revealed subtypes that were either immune defective or immune competent. We analyzed infiltrating stromal and immune cells to further characterize the tumor microenvironment. Elevated expression of macrophage 2 signature genes in the immune competent subtype confirmed that tumor-associated macrophages (TAM) linked inflammation and mutation-driven cancer. A negative correlation was evident between the immune score and the amount of somatic copy-number variation (SCNV) of immune genes (r = -0.58). The SCNVs showed a potential detrimental effect on immunity in the immune-deficient subtype. Knowledge of the genomic alterations in the tumor microenvironment could be used to guide design of immunotherapy options that are appropriate for patients with certain cancer subtypes. Cancer Immunol Res; 6(7); 848-59. ©2018 AACR.


Assuntos
Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/imunologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/imunologia , Transcriptoma , Microambiente Tumoral/genética , Microambiente Tumoral/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Biologia Computacional/métodos , Variações do Número de Cópias de DNA , Feminino , Perfilação da Expressão Gênica , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Mutação , Estadiamento de Neoplasias , Transdução de Sinais , Sequenciamento do Exoma
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