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We report a search for time variations of the solar ^{8}B neutrino flux using 5804 live days of Super-Kamiokande data collected between May 31, 1996, and May 30, 2018. Super-Kamiokande measured the precise time of each solar neutrino interaction over 22 calendar years to search for solar neutrino flux modulations with unprecedented precision. Periodic modulations are searched for in a dataset comprising five-day interval solar neutrino flux measurements with a maximum likelihood method. We also applied the Lomb-Scargle method to this dataset to compare it with previous reports. The only significant modulation found is due to the elliptic orbit of the Earth around the Sun. The observed modulation is consistent with astronomical data: we measured an eccentricity of (1.53±0.35)%, and a perihelion shift of (-1.5±13.5) days.
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AIM: To assess the feasibility of a radiomics model based on unenhanced magnetic resonance imaging (MRI) to differentiate small hepatocellular carcinoma (S-HCC) (≤2 cm) and pre-hepatocellular carcinoma (Pre-HCC). MATERIALS AND METHODS: One hundred and fourteen histopathologically confirmed 114 hepatic nodules were analysed retrospectively. All patients had undergone MRI before surgery using a 3 T MRI system. Each nodule was segmented on unenhanced MRI sequences (T1-weighted imaging [T1] and T2WI with fat-suppression [FS-T2]). Radiomics features were extracted and the optimal features were selected using the least absolute shrinkage and selection operator (LASSO). The support vector machine (SVM) was used to establish the radiomics model. One abdominal radiologist performed the conventional qualitative analysis for classification of S-HCC and Pre-HCC. The diagnostic performances of the radiomics and radiologist models were evaluated using receiver operating characteristic (ROC) analysis. RESULT: Radiomics features (n=1,223) were extracted from each sequence and the optimal features were selected from T1, FS-T2, and T1+FS-T2 to construct the radiomics models. The radiomics model based on T1+FS-T2 showed the best performance among the three models, with areas under the ROC curves (AUCs) of 0.95 (95 % confidence interval [CI], 0.875-0.986) and 0.942 (95 % CI, 0.775-0.985), accuracies of 86 % and 88.5 %, sensitivities of 94.12 % and 100 %, and specificities of 85.48 % and 85.19 %, respectively. The radiomics model on FS-T2 showed better performance on a single sequence than that of the T1-based model. The diagnostic performance for the radiomic model was significantly higher than that for the radiologist (AUC = 0.518, p<0.05). CONCLUSION: This study suggested that a radiomics model based on unenhanced MRI may serve as a feasible and non-invasive tool to classify S-HCC and Pre-HCC.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Lesões Pré-Cancerosas , Humanos , Carcinoma Hepatocelular/diagnóstico por imagem , Estudos Retrospectivos , Radiômica , Neoplasias Hepáticas/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodosRESUMO
A promising accelerator light source mechanism called steady-state microbunching (SSMB) is being actively studied. With the combination of strong coherent radiation from microbunching and high repetition rate of a storage ring, high-average-power narrow-band radiation can be anticipated from an SSMB storage ring, with wavelengths ranging from THz to soft X-ray. Such a novel light source could provide new opportunities for accelerator photon science like high-resolution angle-resolved photoemission spectroscopy and industrial applications like extreme ultraviolet (EUV) lithography. In this paper, a theoretical and numerical study of the average and statistical properties of coherent radiation from SSMB are presented. The results show that 1â kW average-power quasi-continuous-wave EUV radiation can be obtained from an SSMB ring provided that an average current of 1â A and a microbunch train with bunch length of 3â nm can be formed at the radiator which is assumed to be an undulator. Together with the narrow-band feature, the EUV photon flux can reach 6â ×â 1015â photonsâ s-1 within a 0.1â meV energy bandwidth, which is three orders of magnitude higher than that in a conventional synchrotron source and is appealing for fundamental condensed matter physics and other research. In this theoretical investigation, we have generalized the definition and derivation of the transverse form factor of an electron beam which can quantify the impact of its transverse size on coherent radiation. In particular, it has been shown that the narrow-band feature of SSMB radiation is strongly correlated with the finite transverse electron beam size. Considering the pointlike nature of electrons and quantum nature of radiation, the coherent radiation fluctuates from microbunch to microbunch, or for a single microbunch from turn to turn. Some important results concerning the statistical properties of SSMB radiation are presented, with a brief discussion on its potential applications, for example the beam diagnostics. The presented work is of value for the development of SSMB to better serve potential synchrotron radiation users. In addition, this also sheds light on understanding the radiation characteristics of free-electron lasers, coherent harmonic generation, etc.
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The inclusive electron neutrino charged-current cross section is measured in the NOvA near detector using 8.02×10^{20} protons-on-target in the NuMI beam. The sample of GeV electron neutrino interactions is the largest analyzed to date and is limited by ≃17% systematic rather than the ≃7.4% statistical uncertainties. The double-differential cross section in final-state electron energy and angle is presented for the first time, together with the single-differential dependence on Q^{2} (squared four-momentum transfer) and energy, in the range 1 GeV≤E_{ν}<6 GeV. Detailed comparisons are made to the predictions of the GENIE, GiBUU, NEUT, and NuWro neutrino event generators. The data do not strongly favor a model over the others consistently across all three cross sections measured, though some models have especially good or poor agreement in the single differential cross section vs Q^{2}.
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PURPOSE: In HER2-positive breast cancer (HER2+ BC), neoadjuvant chemotherapy (NACT) with dual HER2-targeted therapy achieves high pathologic complete response (pCR) rates. Anthracycline-free NACT regimens avoid toxicities associated with anthracyclines, but every 3-week TCHP also has substantial side effects. We hypothesized that a weekly regimen might have equivalent efficacy with less toxicity; we also investigated whether poorly responding patients would benefit from switching to AC. METHODS: Patients with clinical stage II-III HER2+ BC received weekly paclitaxel 80 mg/m2 and carboplatin AUC2 with every 3-week trastuzumab and pertuzumab (wPCbTP), with the option of splitting the pertuzumab loading dose. After 12 weeks, responding patients continued wPCbTP for another 6 weeks, while non-responders switched to AC. Dose modifications and post-op therapy were at investigator discretion. RESULTS: In 30 evaluable patients, the pCR rate was 77% (95% CI 58-90%); 12/14 (86%) in ER-negative and 11/16 (69%) in ER-positive. Only two patients transitioned to AC for non-response, of which one achieved pCR. There were no episodes of febrile neutropenia or grade ≥ 3 peripheral neuropathy, though several patients who continued wPCbTP stopped before week 18. Split-dose pertuzumab was associated with less grade ≥ 2 diarrhea (40%) than the standard loading dose (60%). CONCLUSION: pCR rates with our regimen were as high as reported with TCHP with fewer grade ≥ 3 toxicities, though diarrhea remains a concern. Too few patients had a suboptimal response to adequately test switching to AC. The wPCbTP regimen should be considered an alternative to TCHP as neoadjuvant therapy for HER2+ BC. TRAIL REGISTRATION: ClinicalTrials.gov identifier: NCT02789657.
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Neoplasias da Mama , Terapia Neoadjuvante , Anticorpos Monoclonais Humanizados , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias da Mama/tratamento farmacológico , Carboplatina/efeitos adversos , Feminino , Humanos , Paclitaxel/efeitos adversos , Receptor ErbB-2/genética , Trastuzumab/efeitos adversos , UniversidadesRESUMO
This Letter reports results from the first long-baseline search for sterile antineutrinos mixing in an accelerator-based antineutrino-dominated beam. The rate of neutral-current interactions in the two NOvA detectors, at distances of 1 and 810 km from the beam source, is analyzed using an exposure of 12.51×10^{20} protons-on-target from the NuMI beam at Fermilab running in antineutrino mode. A total of 121 of neutral-current candidates are observed at the far detector, compared to a prediction of 122±11(stat.)±15(syst.) assuming mixing only between three active flavors. No evidence for ν[over ¯]_{µ}âν[over ¯]_{s} oscillation is observed. Interpreting this result within a 3+1 model, constraints are placed on the mixing angles θ_{24}<25° and θ_{34}<32° at the 90% C.L. for 0.05 eV^{2}≤Δm_{41}^{2}≤0.5 eV^{2}, the range of mass splittings that produces no significant oscillations at the near detector. These are the first 3+1 confidence limits set using long-baseline accelerator antineutrinos.
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Objective: To explore the cut-off point of aldosterone/direct renin ratio (ADRR) before drug washout in the screening for primary aldosteronism (PA) in the Chinese population and reduce the potential risk caused by drug washout during PA screening. Methods: Hospitalized hypertensive patients in the Hypertension Ward of Fuwai Hospital, Chinese Academy of Medical Sciences from January 2017 to October 2019 were enrolled. PA was diagnosed according to the criterion of 2016 American Guideline and 2016 Chinese Consensus for PA. The plasma aldosterone concentration (PAC), direct renin concentration (DRC) and ADRR before and after drug washout were measured. The receiver operating characteristic (ROC) curve of ADRR was drawn and the maximal Youden index was used to determine the best cut-off value. Results: A total of 542 hypertensive patients were included, with 467 patients diagnosed with essential hypertension (EHT) (297 males and 170 females), and 75 patients diagnosed with PA (51 males and 24 females). Patients with PA had higher PAC and ADRR before and after drug washout than those with EHT(150.0 (130.0, 210.0) vs 120.0 (80.0, 170.0) ng/L, 170.0 (120.0, 260.0) vs 130.0 (90.0, 180.0) ng/L; 28.9 (15.9, 63.5) vs 4.3 (1.9, 11.8) (ng/L) / (mU/L) , 55.6 (39.0, 109.0) vs 9.8 (4.5, 21.3) (ng/L) /(mU/L), all P<0.001). However, DRC of PA patients before and after washout were lower than those with EHT (4.0 (2.0, 10.0) vs 27.0 (10.0, 64.0) mU/L, 3.0 (2.0, 4.0) vs 12.2 (5.0, 27.0) mU/L, P<0.001). In EHT and PA groups, PAC and ADRR significantly increased (P=0.001, P<0.001) , but DRC significantly decreased after drug washout (all P<0.001) . The area under the ROC curve of ADRR before drug washout was 0.868 (95%CI 0.836-0.895) with the best cut-off value of 7.8 (ng/L) / (mU/L) for the screening of PA .The sensitivity and specificity was 94.7% and 66.8%, respectively, with the maximal Youden index of 0.615. Conclusion: ADRR before drug washout > 7.8 (ng/L) / (mU/L) can be used as an alternative cut-off point to screen PA when drug washout is not available.
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Hiperaldosteronismo , Hipertensão , Aldosterona , Hipertensão Essencial , Feminino , Humanos , Hiperaldosteronismo/diagnóstico , Masculino , ReninaRESUMO
The cross section of the process e^{+}e^{-}âπ^{+}D^{0}D^{*-} for center-of-mass energies from 4.05 to 4.60 GeV is measured precisely using data samples collected with the BESIII detector operating at the BEPCII storage ring. Two enhancements are clearly visible in the cross section around 4.23 and 4.40 GeV. Using several models to describe the dressed cross section yields stable parameters for the first enhancement, which has a mass of 4228.6±4.1±6.3 MeV/c^{2} and a width of 77.0±6.8±6.3 MeV, where the first uncertainties are statistical and the second ones are systematic. Our resonant mass is consistent with previous observations of the Y(4220) state and the theoretical prediction of a DD[over ¯]_{1}(2420) molecule. This result is the first observation of Y(4220) associated with an open-charm final state. Fits with three resonance functions with additional Y(4260), Y(4320), Y(4360), ψ(4415), or a new resonance do not show significant contributions from either of these resonances. The second enhancement is not from a single known resonance. It could contain contributions from ψ(4415) and other resonances, and a detailed amplitude analysis is required to better understand this enhancement.
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The NOvA experiment has seen a 4.4σ signal of ν[over ¯]_{e} appearance in a 2 GeV ν[over ¯]_{µ} beam at a distance of 810 km. Using 12.33×10^{20} protons on target delivered to the Fermilab NuMI neutrino beamline, the experiment recorded 27 ν[over ¯]_{µ}âν[over ¯]_{e} candidates with a background of 10.3 and 102 ν[over ¯]_{µ}âν[over ¯]_{µ} candidates. This new antineutrino data are combined with neutrino data to measure the parameters |Δm_{32}^{2}|=2.48_{-0.06}^{+0.11}×10^{-3} eV^{2}/c^{4} and sin^{2}θ_{23} in the ranges from (0.53-0.60) and (0.45-0.48) in the normal neutrino mass hierarchy. The data exclude most values near δ_{CP}=π/2 for the inverted mass hierarchy by more than 3σ and favor the normal neutrino mass hierarchy by 1.9σ and θ_{23} values in the upper octant by 1.6σ.
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We report the first measurement of the neutron cross section on argon in the energy range of 100-800 MeV. The measurement was obtained with a 4.3-h exposure of the Mini-CAPTAIN detector to the WNR/LANSCE beam at LANL. The total cross section is measured from the attenuation coefficient of the neutron flux as it traverses the liquid argon volume. A set of 2631 candidate interactions is divided in bins of the neutron kinetic energy calculated from time-of-flight measurements. These interactions are reconstructed with custom-made algorithms specifically designed for the data in a time projection chamber the size of the Mini-CAPTAIN detector. The energy averaged cross section is 0.91±0.10(stat)±0.09(syst) b. A comparison of the measured cross section is made to the GEANT4 and FLUKA event generator packages, where the energy averaged cross sections in this range are 0.60 and 0.68 b, respectively.
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Characteristics of diode-wing-pumped highly efficient Tm:LuAG lasers running both in continuous wave (CW) and electro-optical Q-switching regimes have been investigated. Using a simple plane-plane cavity, a maximum CW output power of 8.5 W has been achieved with a corresponding slope efficiency of 44.5% by "wing pumping" at 790 nm. With a V-shaped cavity, a diode-wing-pumped MgO:LiNbO3 crystal based electro-optically Q-switched Tm:LuAG laser at 2022.9 nm delivered a maximum pulse energy of 10.8 mJ and a minimum pulse width of 52 ns at a corresponding repetition rate of 100 Hz. To the best of our knowledge, the achieved CW output power and Q-switched pulse energy have both set records for all-solid-state Tm:LuAG lasers, which well reveals an efficient way to generate high-power and high-energy lasers at 2 µm wavelength.
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Based on an e^{+}e^{-} collision data sample corresponding to an integrated luminosity of 567 pb^{-1} taken at the center-of-mass energy of sqrt[s]=4.6 GeV with the BESIII detector, we measure the absolute branching fraction of the inclusive decay Λ_{c}^{+}âΛ+X to be B(Λ_{c}^{+}âΛ+X)=(38.2_{-2.2}^{+2.8}±0.9)% using the double-tag method, where X refers to any possible final state particles. In addition, we search for direct CP violation in the charge asymmetry of this inclusive decay for the first time, and obtain A_{CP}≡[B(Λ_{c}^{+}âΛ+X)-B(Λ[over ¯]_{c}^{-}âΛ[over ¯]+X)]/[B(Λ_{c}^{+}âΛ+X)+B(Λ[over ¯]_{c}^{-}âΛ[over ¯]+X)]=(2.1_{-6.6}^{+7.0}±1.6)%, a statistically limited result with no evidence of CP violation.
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We report the first observation of a_{0}^{0}(980)-f_{0}(980) mixing in the decays of J/ψâÏf_{0}(980)âÏa_{0}^{0}(980)âÏηπ^{0} and χ_{c1}âa_{0}^{0}(980)π^{0}âf_{0}(980)π^{0}âπ^{+}π^{-}π^{0}, using data samples of 1.31×10^{9} J/ψ events and 4.48×10^{8} ψ(3686) events accumulated with the BESIII detector. The signals of f_{0}(980)âa_{0}^{0}(980) and a_{0}^{0}(980)âf_{0}(980) mixing are observed at levels of statistical significance of 7.4σ and 5.5σ, respectively. The corresponding branching fractions and mixing intensities are measured and the constraint regions on the coupling constants, g_{a_{0}K^{+}K^{-}} and g_{f_{0}K^{+}K^{-}}, are estimated. The results improve the understanding of the nature of a_{0}^{0}(980) and f_{0}(980).
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Using a data sample of e^{+}e^{-} collisions corresponding to an integrated luminosity of 567 pb^{-1} collected at a center-of-mass energy of sqrt[s]=4.6 GeV with the BESIII detector, we measure the absolute branching fraction of the inclusive semileptonic Λ_{c}^{+} decay with a double-tag method. We obtain B(Λ_{c}^{+}âXe^{+}ν_{e})=(3.95±0.34±0.09)%, where the first uncertainty is statistical and the second systematic. Using the known Λ_{c}^{+} lifetime and the charge-averaged semileptonic decay width of nonstrange charmed mesons (D^{0} and D^{+}), we obtain the ratio of the inclusive semileptonic decay widths Γ(Λ_{c}^{+}âXe^{+}ν_{e})/Γ[over ¯](DâXe^{+}ν_{e})=1.26±0.12.
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Using a low background data sample of 9.7×10^{5} J/ψâγη^{'}, η^{'}âγπ^{+}π^{-} events, which are 2 orders of magnitude larger than those from the previous experiments, recorded with the BESIII detector at BEPCII, the decay dynamics of η^{'}âγπ^{+}π^{-} are studied with both model-dependent and model-independent approaches. The contributions of ω and the ρ(770)-ω interference are observed for the first time in the decays η^{'}âγπ^{+}π^{-} in both approaches. Additionally, a contribution from the box anomaly or the ρ(1450) resonance is required in the model-dependent approach, while the process specific part of the decay amplitude is determined in the model-independent approach.
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Using a data sample corresponding to an integrated luminosity of 2.93 fb^{-1} taken at a center-of-mass energy of 3.773 GeV with the BESIII detector operated at the BEPCII collider, we perform an analysis of the semileptonic decays D^{0(+)}âπ^{-(0)}µ^{+}ν_{µ}. The branching fractions of D^{0}âπ^{-}µ^{+}ν_{µ} and D^{+}âπ^{0}µ^{+}ν_{µ} are measured to be (0.272±0.008_{stat}±0.006_{syst})% and (0.350±0.011_{stat}±0.010_{syst})%, respectively, where the former is of much improved precision compared to previous results and the latter is determined for the first time. Using these results along with previous BESIII measurements of D^{0(+)}âπ^{-(0)}e^{+}ν_{e}, we calculate the branching fraction ratios to be R^{0}≡B_{D^{0}âπ^{-}µ^{+}ν_{µ}}/B_{D^{0}âπ^{-}e^{+}ν_{e}}=0.922±0.030_{stat}±0.022_{syst} and R^{+}≡B_{D^{+}âπ^{0}µ^{+}ν_{µ}}/B_{D^{+}âπ^{0}e^{+}ν_{e}}=0.964±0.037_{stat}±0.026_{syst}, which are compatible with the theoretical expectation of lepton flavor universality within 1.7σ and 0.5σ, respectively. We also examine the branching fraction ratios in different four-momentum transfer square regions, and find no significant deviations from the standard model predictions.
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BACKGROUND: Rapid advancements in biomedical research have accelerated the number of relevant electronic documents published online, ranging from scholarly articles to news, blogs, and user-generated social media content. Nevertheless, the vast amount of this information is poorly organized, making it difficult to navigate. Emerging technologies such as ontologies and knowledge bases (KBs) could help organize and track the information associated with biomedical research developments. A major challenge in the automatic construction of ontologies and KBs is the identification of words with its respective sense(s) from a free-text corpus. Word-sense induction (WSI) is a task to automatically induce the different senses of a target word in the different contexts. In the last two decades, there have been several efforts on WSI. However, few methods are effective in biomedicine and life sciences. METHODS: We developed a framework for biomedical entity sense induction using a mixture of natural language processing, supervised, and unsupervised learning methods with promising results. It is composed of three main steps: (1) a polysemy detection method to determine if a biomedical entity has many possible meanings; (2) a clustering quality index-based approach to predict the number of senses for the biomedical entity; and (3) a method to induce the concept(s) (i.e., senses) of the biomedical entity in a given context. RESULTS: To evaluate our framework, we used the well-known MSH WSD polysemic dataset that contains 203 annotated ambiguous biomedical entities, where each entity is linked to 2-5 concepts. Our polysemy detection method obtained an F-measure of 98%. Second, our approach for predicting the number of senses achieved an F-measure of 93%. Finally, we induced the concepts of the biomedical entities based on a clustering algorithm and then extracted the keywords of reach cluster to represent the concept. CONCLUSIONS: We have developed a framework for biomedical entity sense induction with promising results. Our study results can benefit a number of downstream applications, for example, help to resolve concept ambiguities when building Semantic Web KBs from biomedical text.
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Pesquisa Biomédica , Infecções por HIV/diagnóstico , Informática Médica/métodos , Algoritmos , Inteligência Artificial , Teorema de Bayes , Análise por Conglomerados , Bases de Dados Factuais , Infecções por HIV/epidemiologia , Bases de Conhecimento , Idioma , Aprendizado de Máquina , Processamento de Linguagem Natural , Web Semântica , Semântica , Unified Medical Language System , Vocabulário ControladoRESUMO
Objective: To investigate the expression of Fermintin family homologous protein 2 (FERMT2) in non-small cell lung cancer and its clinical significance. Methods: Seventy-two patients with non-small cell lung cancer were collected at Xinxiang Central Hospital, Henan Province, from January 2015 to January 2017.There were 48 male and 24 female patients, the age ranged from 37 to 78 years (mean 58 years). The expression of FERMT2 in tumor samples and para-cancerous tissues were detected by immunohistochemistry. Protein and mRNA expression of FERMT2 were detected by Western blot and real-time fluorescence quantitative PCR, respectively. Western blot method was also used to detect integrin-related protein expression, including integrin beta 1 (CD29), vascular cell adhesion molecule (VCAM1), and mobile related protein-1 (MRP1). Results: Immunohistochemistry showed that the positive rates of FERMT2 expression were 81.9%(59/72)in carcinoma tissue and 15.4%(11/72) in para-cancerous tissues, and the difference was statistically significant (P<0.01). Positive FERMT2 expression was different in tumors at different tumor stages: 11/17 at stage â , 16/20(80.0%)at stage â ¡, 17/20(85.0%)at stage â ¢, and 15/15 at stage â £, and there was a significant difference between each stage (P<0.01). By real-time PCR and Western blot, the expression of FERMT2 in non-small cell lung cancer tissues was significantly higher than that of para-cancerous tissue (P<0.01). The expression levels of integrin related proteins (integrin ß1, VCAM1 and MRP1) in tumor tissues were significantly higher than those in para-cancerous tissues, and positively correlated with the expression of FERMT2 (r=0.531, P<0.01; r=0.483, P<0.01; r=0.612, P<0.01). Conclusions: FERMT2 is highly expressed in non-small cell lung carcinomas. Its expression is closely correlated with the tumor clinical stage. It is hypothesized that FERMT2 may promote tumor metastasis through interactions with integrin-like protein.
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Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Adulto , Idoso , Western Blotting , Feminino , Humanos , Imuno-Histoquímica , Masculino , Proteínas de Membrana , Pessoa de Meia-Idade , Proteínas de Neoplasias , Reação em Cadeia da Polimerase em Tempo RealRESUMO
A Tm3+ ion and Y3+ ion co-doped CaF2 crystal was grown and characterized, in which spectral and lasing performance was presented for the first time, to the best of our knowledge. Under diode end-pumping, in a continuous-wave regime, maximum output power of 453 mW was delivered under an absorption pump power of 2.5 W, corresponding to an optical-to-optical conversion efficiency of 17.9% and a slope efficiency of 21%. With a birefringent quartz plate, wavelength-tunable operation with a tunable range of more than 190 nm was realized. The results show that Tm,Y:CaF2 is a promising laser crystal operating in a spectral region ranging from 1850 nm to 2050 nm.