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Using Bayesian spectroscopy, we performed spectral decomposition of gate modulation (GM) spectra measured in a pentacene organic field-effect transistor to understand comprehensively the optical nonlinear response due to GM and hole injection. Although GM spectra contain a variety of spectral components, by Bayesian spectroscopy, we can specify the role of each component in the nonlinear response by performing model selection that chooses the spectral components needed to explain the data without preconceptions. For a GM spectrum under positive GM, Bayesian spectroscopy shows that nonlinear responses by the change in polarizability dominate the GM spectrum among several types of Stark signals induced by the GM electric field, which is a physically valid conclusion. For GM spectra under negative GM where gate-induced carriers are injected, Bayesian spectroscopy succeeds in completely elucidating the spectral structure, which is composed of the two types of Stark signals due to changes in the polarizability and the dipole moment, bleaching, and gate-induced absorption signals. A pentacene film is known to have solid and isolated molecular phases, which may give different spectral responses. Therefore, we compared a model that treats these responses equally and a model that distinguishes them. Bayesian spectroscopy selects the latter models for all GM spectra, revealing statistically that nonlinear optical effects and hole injection effects are different in these phases. [ABSTRACT FROM AUTHOR]

We analyzed the X-ray photoelectron spectra (XPS) of carbon 1s states in graphene and oxygen-intercalated graphene grown on SiC(0001) using Bayesian spectroscopy. To realize highly accurate spectral decomposition of the XPS spectra, we proposed a framework for discovering physical constraints from the absence of prior quantified physical knowledge, in which we designed the prior probabilities based on the found constraints and the physically required conditions. This suppresses the exchange of peak components during replica exchange Monte Carlo iterations and makes possible to decompose XPS in the case where a reliable structure model or a presumable number of components is not known. As a result, we have successfully decomposed XPS of one monolayer (1ML), two monolayers (2ML), and quasi-freestanding 2ML (qfs-2ML) graphene samples deposited on SiC substrates with the meV order precision of the binding energy, in which the posterior probability distributions of the binding energies were obtained distinguishably between the different components of buffer layer even though they are observed as hump and shoulder structures because of their overlapping. [ABSTRACT FROM AUTHOR]

We analyzed the X-ray photoelectron spectra (XPS) of carbon 1s states in graphene and oxygen-intercalated graphene grown on SiC(0001) using Bayesian spectroscopy. To realize highly accurate spectral decomposition of the XPS spectra, we proposed a framework for discovering physical constraints from the absence of prior quantified physical knowledge, in which we designed the prior probabilities based on the found constraints and the physically required conditions. This suppresses the exchange of peak components during replica exchange Monte Carlo iterations and makes possible to decompose XPS in the case where a reliable structure model or a presumable number of components is not known. As a result, we have successfully decomposed XPS of one monolayer (1ML), two monolayers (2ML), and quasi-freestanding 2ML (qfs-2ML) graphene samples deposited on SiC substrates with the meV order precision of the binding energy, in which the posterior probability distributions of the binding energies were obtained distinguishably between the different components of buffer layer even though they are observed as hump and shoulder structures because of their overlapping. [ABSTRACT FROM AUTHOR]

This article presents a Bayesian sparse modeling method to analyze extended x-ray absorption fine structure (EXAFS) data with basis functions built on two-body signals. This method does not require any structural model and allows us to evaluate regression coefficients proportional to the radial distribution functions of the respective elements and their errors and is very effective for analysis of EXAFS with weak absorption intensity and severe signal-to-noise ratios. As an application example, we used it to analyze the EXAFS of an yttrium oxyhydride (YOxHy) epitaxial thin film. These EXAFS data show weak absorption intensity and a severe signal-to-noise ratio due to the small amount of x-ray absorption in the thin film sample. However, this approach revealed that the radial distance ratio of the second neighbor yttrium to the first neighbor oxygen coincides with that of a tetrahedral configuration. This result demonstrates that the interstitial oxygen position is tetrahedral in the YOxHy thin film. [ABSTRACT FROM AUTHOR]

Abstract: We report here a case of a 44-year-old female with a pulmonary varix. The patient was asymptomatic; a routine chest X-ray incidentally revealed a serpiginous mass in the left hilar region. Computed tomography revealed a serpiginous, dilated vascular structure in the left upper lobe that continued into the lower lobe and was suggestive of an arteriovenous malformation. Pulmonary angiography revealed no arterial abnormality; however, the filling of an abnormally dilated pulmonary vein was observed. Angiography is considered to be the most useful method for the confirmatory diagnosis of pulmonary varices. [Copyright &y& Elsevier]

We proposed a data-driven science study by Bayesian spectroscopy to analyze an X-ray magnetic circular dichroism (XMCD) spectrum and magnetic moments. In Bayesian spectroscopy, model selection becomes available to estimate the number of spectral components by using Bayes free energy. To demonstrate such advantage, we decomposed synthesized X-ray absorption (XA) and XMCD spectra at the L 3 , 2 -absorption edge of the Ni ion in NiFe 2 O 4 . In the synthesized ∓ helicity XA spectra, random noise was superimposed and a finite spectral width was convolved to mimic measured spectra. From these XA spectra, spectral components having intensity beyond the noise level were successfully extracted without excess or deficiency although transition components in close proximity within the spectral width were merged. From the XMCD spectrum, we also succeeded in extracting separately the original ∓ helicity components although an additional − helicity component comparing with the case of XA spectra was extracted in the model selection. This additional component was extracted to explain an asymmetric XMCD spectral structure at the L 3 edge, and this result demonstrates that Bayesian spectroscopy can fully exploit the advantage of XMCD measurements being superior for detecting close transition components of opposite helicities. In addition, we proposed to use posterior probability distributions obtained by Bayesian spectroscopy for estimating magnetic moments through samplings of the spectral intensities for the separately decomposed ∓ helicity components on the L 3 , 2 -absorption edge. [ABSTRACT FROM AUTHOR]

Dielectric polymers such as polyethylene (PE) have a wide range of energy and electronic applications. While recent studies have shown significant effects of chemical defects on the electronic structure of PE, those on the dielectric properties remain elusive. Here, first-principles quantum-mechanical calculations show anisotropic dielectric constants of PE, which are sensitive to the type of defects. Specifically, addition of iodine defects increases the high-frequency dielectric constant. Addition of hydroxyl or carboxyl group, on the other hand, causes noticeable anisotropic changes in the static dielectric constant, which is well elucidated through the rotation and concerted motions of chemical groups. The sensitivity of these defects may be exploited to rationally alter the behavior of PE. [ABSTRACT FROM AUTHOR]

Background: It has long been thought that small‐cell lung cancer (SCLC) is a central type of tumor that is located in the proximal bronchi and the mediastinum. However, several studies reported that SCLC exhibited several types of spread pattern on computed tomography (CT). The aim of this study is to investigate the relationship between CT images and clinical characteristics in patients with SCLC. Methods: We retrospectively reviewed the CT images of 92 SCLC patients and classified them into six types of spreading patterns: central, peripheral, lymphangitic spread (LYM), pleural dissemination (PLE), lobar replacement (LOB), and air‐space consolidation (AC). We also evaluated the correlation between primary tumor location and the clinical characteristics of patients. Results: The most common type of imaging pattern was peripheral (n = 40, 44%), with the next most common type being central (n = 27, 29%). Atypical types of SCLC, such as LYM (n = 2, 2%), PLE (n = 4, 4%), LOB (n = 8, 9%), and AC (n = 11, 12%), were also recognized in our study. The prevalence of emphysema and interstitial lung disease (ILD) was significantly higher in the peripheral type than in the central type (p = 0.0056 and p = 0.0403, respectively). Meanwhile, no survival difference was seen between the central type and the peripheral type (median months 17.9 vs. 21.9, respectively, p = 0.720). Conclusions: The peripheral type of tumor was correlated with higher prevalence of emphysema and ILD in SCLC. Our result suggests different mechanisms of development and tumor characteristics according to tumor location. [ABSTRACT FROM AUTHOR]

Objective: This study examined the clinical significance of intra-alveolar fibrin deposition (IAFD) in transbronchial lung biopsy specimens obtained from patients with organizing pneumonia. Methods: Pathological reports of transbronchial lung biopsies performed between 2004 and 2012 were reviewed to identify cases of intra-alveolar organization with or without fibrin deposition. Clinical charts, computed tomography images, and transbronchial lung biopsy specimens from these cases were examined retrospectively. Diagnosis of organizing pneumonia was reevaluated based upon the consensus of a respiratory physician, a radiologist, and a pathologist. Results: Transbronchial lung biopsy results of the reviewed patients with organizing pneumonia found seven patients who had IAFD, and 34 who did not. Seven patients' conditions were associated with collagen vascular disease (CVD), and 34 were cryptogenic. IAFD was significantly associated with high C-reactive protein (CRP) values (>5 mg/dl) ( p = 0.0012) and underlying CVD ( p = 0.0099). Multivariate analysis revealed that IAFD was independently associated with high CRP values ( p = 0.0184). Three of 31 patients and six of 27 patients experienced a relapse of organizing pneumonia within 6 months and 1 year, respectively. IAFD ( p = 0.0044) and high CRP values ( p = 0.0207) were significantly related to relapse within 6 months, while only CRP was significantly related to relapse within 1 year ( p = 0.0007). Conclusion: In patients with organizing pneumonia, IAFD was significantly associated with high CRP values. High CRP values and/or IAFD predicted relapse of organizing pneumonia within 6 months to 1 year. [ABSTRACT FROM AUTHOR]

A chest roentgenogram of a 75-year-old immunocompetent woman showed disseminated micronodular densities in bilateral lung fields. Subsequent high-resolution computed tomography (CT) confirmed centrilobular micronodular densities associated with bronchial wall thickening and bronchiectatic changes. CT imaging also revealed volume loss with bronchiectatic changes in both the right middle lobe and the left lingular segment. Cytology specimens were then obtained through bronchial brushing and washes. Smears from right B2 and B4 revealed filamentous gram-positive, branched bacteria embedded among many neutrophils. Nocardia transvalensis was cultured from the bronchial wash, and no mycobacteria were identified. To our knowledge, this is the first report of a Nocardia transvalensis pulmonary infection in an immunocompetent patient, and also the first detailed description of a Nocardia transvalensis pulmonary infection in Japan. Moreover, the radiographic and CT findings in this patient were quite similar to those seen in patients with nontuberculous mycobacterial pulmonary infections, a pattern not previously reported in patients with Nocardia pulmonary infections. [ABSTRACT FROM AUTHOR]

Objective. This study aimed to examine the nutritional status and nutrient intake of patients with MAC lung disease with a focus on visceral fat area. Patients and Methods. Among 116 patients of our hospital with nontuberculous mycobacteriosis who were registered between May 2010 and August 2011, 103 patients with MAC lung disease were included in this study. In all patients, nutritional status and nutrient intake were prospectively examined. Results. Patients were 23 men and 80 women (mean age, 72.3±10.9 years). BMI (kg/m2) at the time of registration was 20.4±2.7 in men and 19.2±2.9 in women. Visceral fat area (cm2) was significantly lower in women (35.7±26.6) than in men (57.5±47.4) (p=0.0111). The comparison with general healthy adults according to age revealed a markedly reduced visceral fat area among patients with MAC lung disease. With respect to nutrient intake, energy adequacy (86.1±15.7%), protein adequacy (82.4±18.2%), lipid adequacy (78.1±21.8%), and carbohydrate adequacy (89.6±19.2%) ratios were all low at the time of registration. BMI was significantly correlated with protein adequacy (p=0.0397) and lipid adequacy (p=0.0214) ratios, while no association was found between visceral fat area and nutrient intake. Conclusion. Patients with MAC lung disease had a low visceral fat area and low nutrient intake. [ABSTRACT FROM AUTHOR]

Here we report the case of a 72-year-old woman with nodular bronchiectatic Mycobacterium avium complex (MAC) disease. Chest computed tomography on admission revealed multiple micronodular and branching opacities in both lobes with segmental distribution; bronchiectasis and bronchial wall thickening were observed in the middle lobe and lingula. The patient consented to and underwent thoracoscopic lung biopsy; epithelioid granulomas were occasionally observed, but follicular bronchiolitis was widespread. While bronchial lesions from nontuberculous mycobacterial infection generally present as epitheliod granulomas, the present case suggests that follicular bronchiolitis can also be a histological counterpart to nodular opacities in nodular bronchiectatic MAC disease. [ABSTRACT FROM AUTHOR]

Although gate modulation (GM) spectroscopy performed by combining optical measurements with gate bias application in a field effect transistor (FET) is one of the most straightforward techniques for electronic state evaluation of operating FETs, the origin of the spectral response to the gate bias application has not been fully elucidated. We here address the origin of the GM signals from variety of GM spectroscopic techniques performed for pentacene-based organic FETs. The GM spectrum under the negative gate bias in the condition that the source and drain electrodes are short-circuited exhibits a complicated lineshape with many unresolved peaks. We demonstrate that the GM signal under FET driving condition with drain bias applied is dominated by second-derivative (SD) Stark signals. From the comparison of the first and second harmonic response GM signals, the SD-Stark signal is found to be given by local electric fields from hole carriers injected from the electrodes, rather than given by an external electric field from the gate-bias. The SD signal intensity is enhanced when a high degree of molecular orientation exists around the carriers, thus the SD signal can be used to investigate molecular orientation around gate-induced carriers. Image 1 • Gate bias application causes Stark signals as well as carrier signals in OFETs. • Gate modulation spectroscopy under drain bias applied is performed. • Stark signals arise from local electric field by injected hole carriers. • Molecular orientation around carriers can be examined by gate-induced Stark signals. [ABSTRACT FROM AUTHOR]