Automation of etch pit analyses on solid-state nuclear track detectors with machine learning for laser-driven ion acceleration.

Solid-state nuclear track detectors (SSNTDs) are often used as ion detectors in laser-driven ion acceleration experiments and are considered to be the most reliable ion diagnostics since they are sensitive only to ions and measure ions one by one. However, ion pit analyses require tremendous time and effort in chemical etching, microscope scanning, and ion pit identification by eyes. From a laser-driven ion acceleration experiment, there are typically millions of microscopic images, and it is practically impossible to analyze all of them by hand. This research aims to improve the efficiency and automation of SSNTD analyses for laser-driven ion acceleration. We use two sets of data obtained from calibration experiments with a conventional accelerator where ions with known nuclides and energies are generated and from actual laser experiments using SSNTDs. After chemical etching and scanning the SSNTDs with an optical microscope, we use machine learning to distinguish the ion etch pits from noises. From the results of the calibration experiment, we confirm highly accurate etch-pit detection with machine learning. We are also able to detect etch pits with machine learning from the laser-driven ion acceleration experiment, which is much noisier than calibration experiments. By using machine learning, we successfully identify ion etch pits ∼105 from more than 10 000 microscopic images with a precision of ≳95%. A million microscopic images can be examined with a recent entry-level computer within a day with high precision. Machine learning tremendously reduces the time consumption on ion etch pit analyses detected on SSNTDs.

Mass-resolved ion measurement by particle counting analysis for characterizing relativistic ion beams driven by lasers.

Particle counting analysis is a possible way to characterize GeV-scale, multi-species ions produced in laser-driven experiments. We present a multi-layered scintillation detector to differentiate multi-species ions of different masses and energies. The proposed detector concept offers potential advantages over conventional diagnostics in terms of (1) high sensitivity to GeV ions, (2) realtime analysis, and (3) the ability to differentiate ions with the same charge-to-mass ratio. A novel choice of multiple scintillators with different ion stopping powers results in a significant difference in energy deposition between the scintillators, allowing accurate particle identification in the GeV range. Here, we report a successful demonstration of particle identification for heavy ions, performed at the Heavy Ion Medical Accelerator in Chiba. In the experiment, the proposed detector setup showed the ability to differentiate particles with similar atomic numbers, such as C6+ and O8+ ions, and provided an excellent energy resolution of 0.41%-1.2% (including relativistic effect, 0.51%--1.6%).

A multi-stage scintillation counter for GeV-scale multi-species ion spectroscopy in laser-driven particle acceleration experiments.

Particle counting analysis (PCA) with a multi-stage scintillation detector shows a new perspective on angularly resolved spectral characterization of GeV-scale, multi-species ion beams produced by high-power lasers. The diagnosis provides a mass-dependent ion energy spectrum based on time-of-flight and pulse-height analysis of single particle events detected through repetitive experiments. With a novel arrangement of multiple scintillators with different ions stopping powers, PCA offers potential advantages over commonly used diagnostic instruments (CR-39, radiochromic films, Thomson parabola, etc.) in terms of coverage solid angle, detection efficiency for GeV-ions, and real-time analysis during the experiment. The basic detector unit was tested using 230-MeV proton beam from a synchrotron facility, where we demonstrated its potential ability to discriminate major ion species accelerated in laser-plasma experiments (i.e., protons, deuterons, carbon, and oxygen ions) with excellent energy and mass resolution. The proposed diagnostic concept would be essential for a better understanding of laser-driven particle acceleration, which paves the way toward all-optical compact accelerators for a range of applications.

Effects of prior osteoporosis treatment on the treatment response of romosozumab followed by denosumab in patients with postmenopausal osteoporosis.

In patients with postmenopausal osteoporosis, prior osteoporosis treatment affected the bone mineral density increase of following treatment with 12 months of romosozumab, although it did not affect that of following treatment with 12 months of denosumab after romosozumab. PURPOSE: To investigate the effects of prior osteoporosis treatment on the response to treatment with romosozumab (ROMO) followed by denosumab (DMAb) in patients with postmenopausal osteoporosis. METHODS: In this prospective, observational, multicenter study, treatment-naïve patients (Naïve; n = 55) or patients previously treated with bisphosphonates (BP; n = 37), DMAb (DMAb; n = 45) or teriparatide (TPTD; n = 17) (mean age, 74.6 years; T-scores of the lumbar spine [LS] - 3.2 and total hip [TH] - 2.6) were switched to ROMO for 12 months, followed by DMAb for 12 months. Bone mineral density (BMD) and serum bone turnover markers were evaluated for 24 months. RESULTS: A BMD increase was observed at 12 and 24 months in the following patients: Naïve (18.2% and 22.0%), BP (10.2% and 12.1%), DMAb (6.6% and 9.7%), and TPTD (10.8% and 15.0%) (P < 0.001 between the groups at both 12 and 24 months) in LS and Naïve (5.5% and 8.3%), BP (2.9% and 4.1%), DMAb (0.6% and 2.2%), and TPTD (4.3% and 5.4%) (P < 0.01 between the groups at 12 months and P < 0.001 at 24 months) in TH, respectively. The BMD increase in LS from 12 to 24 months was negatively associated with the levels of bone resorption marker at 24 months. Incidences of major fragility fractures for the respective groups were as follows: Naïve (5.5%), BP (16.2%), DMAb (11.1%), and TPTD (5.9%). CONCLUSIONS: Previous treatment affected the BMD increase of following treatment with ROMO, although it did not affect that of following treatment with DMAb after ROMO.

Robustness of large-area suspended graphene under interaction with intense laser.

Graphene is known as an atomically thin, transparent, highly electrically and thermally conductive, light-weight, and the strongest 2D material. We investigate disruptive application of graphene as a target of laser-driven ion acceleration. We develop large-area suspended graphene (LSG) and by transferring graphene layer by layer we control the thickness with precision down to a single atomic layer. Direct irradiations of the LSG targets generate MeV protons and carbons from sub-relativistic to relativistic laser intensities from low contrast to high contrast conditions without plasma mirror, evidently showing the durability of graphene.

Energetic α-particle sources produced through proton-boron reactions by high-energy high-intensity laser beams.

In an experiment performed with a high-intensity and high-energy laser system, α-particle production in proton-boron reaction by using a laser-driven proton beam was measured. α particles were observed from the front and also from the rear side, even after a 2-mm-thick boron target. The data obtained in this experiment have been analyzed using a sequence of numerical simulations. The simulations clarify the mechanisms of α-particle production and transport through the boron targets. α-particle energies observed in the experiment and in the simulation reach 10-20 MeV through energy transfer from 20-30 MeV energy incident protons. Despite the lower cross sections for protons with energy above the sub-MeV resonances in the proton-boron reactions, 10^{8}-10^{9}α particles per steradian have been detected.

Growth activation of influenza virus by trypsin and effect of T-705 (favipiravir) on trypsin-optimized growth condition.

Influenza virus is activated by proteolytic cleavage of hemagglutinin by trypsin. After determining the optimal trypsin concentration, intracellular and extracellular influenza A/PR/8/34 (H1N1) and A/Victoria/361/2011 (H3N2) virus productions were compared in cultures treated with T-705 (favipiravir) and GS 4071 (an active form of oseltamivir). Although both drugs efficiently inhibited extracellular viral RNA release in a dose-dependent manner, T-705 inhibited it to the level of the inoculum without trypsin treatment, while GS 4071 inhibited it to a final level 10 times higher than that without trypsin. T-705 inhibited intracellular viral RNA production to the level of input virus in both trypsin-treated and untreated cells. In contrast, GS 4071 dose-dependently inhibited intracellular viral RNA production in cells treated with trypsin but allowed viral RNA synthesis. The level of maximum inhibition by GS 4071was 10 times higher than that of cells without trypsin and 1,000 times greater than the inoculum titer in cells without trypsin. T-705 inhibited both intracellular and extracellular virus production 1,000 and 10 times more strongly, respectively, than GS 4071. T-705 has powerful anti-influenza activity in the absence of trypsin and even in the trypsin-optimized growth condition, suggesting the therapeutic advantage in treatment of influenza complicated with bacterial pneumonia. Keywords: influenza; T-705; Tamiflu; trypsin; bacterial trypsin-like protease.

NOVEL ANALYTICAL STUDY FOR REACTION INTERMEDIATES IN THE PRIMARY RADIATION INTERACTION OF DNA USING A SYNCHROTRON RADIATION-INDUCED LUMINESCENCE SPECTROSCOPY.

To identify the precise molecular processes to induce DNA lesions, we attempt a novel spectroscopy of X-ray induced luminescence (XIL) using soft X-ray synchrotron radiation, which is a non-destructive analysis of the reaction intermediates in the elementary reaction pathway of damage induction and self-organized restoration. Using a liquid micro-jet technique to introduce aqueous samples in a vacuum chamber, we measure UV-visible luminescence from nucleotide solution as a function of the soft X-ray energy from the nitrogen to oxygen K-edge region. The XIL intensities for the nucleotide solutions are significantly enhanced in the soft X-ray region (410-530 eV) which is ascribed to the K-shell excitation/ionization of nitrogen atoms in the nucleobases. Furthermore, the XIL spectra do not show any signature of X-ray absorption near-edge structure (XANES) of the nucleobases. This is because the luminescence intensities collected from the integral area of the micro-jet only reflect the quantum yield of luminescence of the absorbed X-ray into UV-visible light irrespective of the absorption cross sections, i.e. of XANES. Thus the present result is the first evidence of luminescence as a result of X-ray absorption of aqueous nucleotides.

Subjective Well-Being Is Associated with Food Behavior and Demographic Factors in Chronically Ill Older Japanese People Living Alone.

OBJECTIVES: This study aimed to examine the relationships among subjective well-being, food and health behaviors, socioeconomic factors, and geography in chronically ill older Japanese adults living alone. DESIGN: The design was a cross-sectional, multilevel survey. A questionnaire was distributed by post and self-completed by participants. SETTING: The sample was drawn from seven towns and cities across Japan. PARTICIPANTS: A geographic information system was used to select a representative sample of older people living alone based on their proximity to a supermarket. Study recruitment was conducted with municipal assistance. MEASUREMENTS: To assess subjective well-being and food and health behaviors of respondents with disease, a logistic regression analysis was performed using stepwise variable analyses, adjusted for respondent age, socioeconomic status, and proximity to a supermarket. The dependent variable was good or poor subjective well-being. RESULTS: In total, 2,165 older people (744 men, 1,421 women) completed the questionnaire (63.5% response rate). Data from 737 men and 1,414 women were used in this study. Among people with a chronic disease, individuals with good subjective well-being had significantly higher rates than those with poor subjective well-being for satisfaction with meal quality and chewing ability, food diversity, food intake frequency, perception of shopping ease, having someone to help with food shopping, eating home-produced vegetables, preparing breakfast themselves, eating with other people, and high alcohol consumption. A stepwise logistic analysis showed that the factors strongly related to poor subjective well-being were shopping difficulty (men: odds ratio [OR] = 3.19, 95% confidence interval [CI], 1.94-5.23; P < 0.0001; women: OR = 2.20, 95% CI, 1.54-3.14; P < 0.0001), not having someone to help with food shopping (women: OR = 1.41, 95% CI, 1.01-1.97; P = 0.043), not preparing breakfast (women: OR = 2.36, 95% CI, 1.40-3.98; P = 0.001), and eating together less often (women: OR = 1.99, 95% CI, 1.32-3.00; P = 0.002). CONCLUSION: Subjective well-being of people with chronic diseases is associated with food intake and food behavior. The factors that affect poor subjective well-being in chronically ill older Japanese people living alone include food accessibility and social communication.

Burst intensification by singularity emitting radiation in multi-stream flows.

Burst Intensification by Singularity Emitting Radiation (BISER) is proposed. Singularities in multi-stream flows of emitting media cause constructive interference of emitted travelling waves, forming extremely localized sources of bright coherent emission. Here we for the first time demonstrate this extreme localization of BISER by direct observation of nano-scale coherent x-ray sources in a laser plasma. The energy emitted into the spectral range from 60 to 100 eV is up to ~100 nJ, corresponding to ~1010 photons. Simulations reveal that these sources emit trains of attosecond x-ray pulses. Our findings establish a new class of bright laboratory sources of electromagnetic radiation. Furthermore, being applicable to travelling waves of any nature (e.g. electromagnetic, gravitational or acoustic), BISER provides a novel framework for creating new emitters and for interpreting observations in many fields of science.

Characterization of micron-size hydrogen clusters using Mie scattering.

Hydrogen clusters with diameters of a few micrometer range, composed of 108-10 hydrogen molecules, have been produced for the first time in an expansion of supercooled, high-pressure hydrogen gas into a vacuum through a conical nozzle connected to a cryogenic pulsed solenoid valve. The size distribution of the clusters has been evaluated by measuring the angular distribution of laser light scattered from the clusters. The data were analyzed based on the Mie scattering theory combined with the Tikhonov regularization method including the instrumental functions, the validity of which was assessed by performing a calibration study using a reference target consisting of standard micro-particles with two different sizes. The size distribution of the clusters was found discrete peaked at 0.33 ± 0.03, 0.65 ± 0.05, 0.81 ± 0.06, 1.40 ± 0.06 and 2.00 ± 0.13 µm in diameter. The highly reproducible and impurity-free nature of the micron-size hydrogen clusters can be a promising target for laser-driven multi-MeV proton sources with the currently available high power lasers.

Scintillator-based transverse proton beam profiler for laser-plasma ion sources.

A high repetition rate scintillator-based transverse beam profile diagnostic for laser-plasma accelerated proton beams has been designed and commissioned. The proton beam profiler uses differential filtering to provide coarse energy resolution and a flexible design to allow optimisation for expected beam energy range and trade-off between spatial and energy resolution depending on the application. A plastic scintillator detector, imaged with a standard 12-bit scientific camera, allows data to be taken at a high repetition rate. An algorithm encompassing the scintillator non-linearity is described to estimate the proton spectrum at different spatial locations.

"Eating Together" Is Associated with Food Behaviors and Demographic Factors of Older Japanese People Who Live Alone.

OBJECTIVE: This study aimed to examine the relationships between eating together and subjective health, frailty, food behaviors, food accessibility, food production, meal preparation, alcohol intake, socioeconomic factors and geography among older Japanese people who live alone. DESIGN: A cross-sectional, multilevel survey was designed. The questionnaire was distributed by post and self-completed by participants. SETTING: The sample was drawn from seven towns and cities across Japan. PARTICIPANTS: A geographic information system was used to select a representative sample of older people who lived alone based on their proximity to a supermarket. Recruitment for the study was conducted with municipal assistance. MEASUREMENTS: A logistic regression analysis was performed that adjusted for the respondent's age, socioeconomic status and proximity to a supermarket using stepwise variable analyses. The dependent variable was whether the respondent ate together more or less than once a month. RESULTS: In total, 2,196 older people (752 men and 1,444 women) completed the questionnaire (63.5% response rate). It was found that 47.1% of men and 23.9% of women ate together less than once a month. Those who ate together less than once a month had a significantly lower rate of subjective health, food diversity and food intake frequency than those who ate together more often. A stepwise logistic analysis showed that the factors most strongly related to eating together less than once a month were not having any food shopping assistance (men: OR = 3.06, women: OR = 2.71), not receiving any food from neighbors or relatives (men: OR = 1.74, women: OR = 1.82), daily alcohol intake (women: OR = 1.83), frailty (men: OR = 0.48) and income (men: OR = 2.16, women: OR = 1.32). CONCLUSION: Eating together is associated with subjective health and food intake. Factors that affect how often older Japanese people who live alone eat together include food accessibility, daily alcohol intake, frailty and a low income.

Association between Satisfaction with State of Health and Meals, Physical Condition and Food Diversity, Health Behavior, and Perceptions of Shopping Difficulty among Older People Living Alone in Japan.

OBJECTIVE: This study aimed to examine perceptions of shopping difficulty, and the relationships with satisfaction with state of health and meals, physical condition, food diversity and health behavior in older people living alone in Japan. DESIGN: A cross-sectional, multilevel survey was designed. The questionnaire was distributed by mail and self-completed by participants. SETTING: The sample was drawn from seven towns and cities across Japan. PARTICIPANTS: A geographic information system was used to select the sample of older people living alone, by proximity to a supermarket. In total, 2,346 older people (827 men and 1,519 women) completed the questionnaire. MEASUREMENTS: The dependent variable was whether shopping was easy or difficult. A logistic regression analysis was performed, adjusting for age, socioeconomic status and proximity of residence to a supermarket using stepwise variable analyses. RESULTS: The response rate was 67.8%. Overall, 14.5% of men and 21.7% of women considered shopping difficult. The stepwise logistic analysis showed that the factors most strongly related to shopping difficulty were a subjective feeling of poor health (men: OR = 3.01, women: OR = 2.16) and lack of satisfaction with meals (men: OR = 2.82, women: OR = 3.69). Other related physical condition and dietary factors were requiring nursing care (men: OR = 3.69, women: OR = 1.54), a high level of frailty, measured using the frailty index score (women: OR = 0.36) and low food diversity score (men: OR = 1.84, women: OR = 1.36). CONCLUSION: The study found that older people's assessment of their shopping difficulty was related to satisfaction aspects, including a subjective feeling of poor health, and lack of satisfaction with meals, as well as physical condition. These have a greater influence on shopping difficulty than income in both sexes, and proximity to a supermarket in women.

Clonal structure in Ichthyobacterium seriolicida, the causative agent of bacterial haemolytic jaundice in yellowtail, Seriola quinqueradiata, inferred from molecular epidemiological analysis.

Bacterial haemolytic jaundice caused by Ichthyobacterium seriolicida has been responsible for mortality in farmed yellowtail, Seriola quinqueradiata, in western Japan since the 1980s. In this study, polymorphic analysis of I. seriolicida was performed using three molecular methods: amplified fragment length polymorphism (AFLP) analysis, multilocus sequence typing (MLST) and multiple-locus variable-number tandem repeat analysis (MLVA). Twenty-eight isolates were analysed using AFLP, while 31 isolates were examined by MLST and MLVA. No polymorphisms were identified by AFLP analysis using EcoRI and MseI, or by MLST of internal fragments of eight housekeeping genes. However, MLVA revealed variation in repeat numbers of three elements, allowing separation of the isolates into 16 sequence types. The unweighted pair group method using arithmetic averages cluster analysis of the MLVA data identified four major clusters, and all isolates belonged to clonal complexes. It is likely that I. seriolicida populations share a common ancestor, which may be a recently introduced strain.

Food Accessibility and Perceptions of Shopping Difficulty among Elderly People Living Alone in Japan.

OBJECTIVES: This aim of this study was to describe the association between shopping difficulty and food accessibility for elderly people living alone in Japan. DESIGN: A cross-sectoral, multilevel survey was designed to measure shopping difficulty from a food accessibility perspective. The questionnaire was distributed by mail. SETTING: The sample was drawn from seven towns and cities across Japan. PARTICIPANTS: A geographic information system was used to select the sample: it identified the proximity of elderly people living alone to a supermarket. In total, 2,028 elderly people (725 men and 1,303 women) responded to the questionnaire. MEASUREMENTS: The binary dependent variables were shopping is easy/shopping is difficult. A logistic regression analysis adjusting for age and area of residence and using stepwise variable analyses was performed. RESULTS: The response rate was 58.6%. Overall, 14.6% of elderly men and 21.7% of elderly women consider shopping difficult. The stepwise logistic analysis showed that the food accessibility factors strongly related to shopping difficulty are infrequent car use (women: OR = 6.97), walking difficulties (men: OR = 2.81, women: OR = 3.48), poor eyesight (men: OR = 2.26, women: OR = 1.75), not cooking lunch by oneself (men: OR = 1.63, women: OR = 1.72), not having anyone to help with food shopping (women: OR = 1.45) and living over 1 km away from a supermarket (men: OR = 2.30, women: OR = 2.97). CONCLUSION: The study concludes that elderly people's assessment of shopping difficulty is related to their food accessibility. Important food accessibility aspects include car or motorbike ownership, walking continuously for 1 km, poor eyesight, and having cooking skills and having someone to help with shopping. These physical activity restrictions have a greater influence on shopping difficulty than do either income or proximity to a supermarket.

Efficacy and Safety of High-Dose Mizoribine Combined With Cyclosporine, Basiliximab, and Corticosteroids in Renal Transplantation: A Japanese Multicenter Study.

Mizoribine (MZR) is an immunosuppressive agent that exhibits a less potent immunosuppressive effect at doses up to 3 mg/kg/d. We investigated whether high-dose MZR is effective and safe for renal transplant patients in conjunction with cyclosporine (CsA), basiliximab, and corticosteroids. Ninety Japanese renal transplant patients were administered MZR (6 mg/kg/d), CsA (7 mg/kg/d), prednisolone (maintenance dose, 10 mg/d), and basiliximab (20 mg/body). They were compared with a control group of 81 renal transplant patients who received mycophenolate mofetil (MMF; 1500 mg/d), CsA, prednisolone, and basiliximab. The 2-year patient and graft survival rates were 98.9% and 97.8% in the MZR group and 98.8% and 97.5% in the MMF group, respectively. The rejection rate within 2 years after transplantation was 21.1% in the MZR group and 16.0% in the MMF group; the difference was nonsignificant. None of the MZR group developed cytomegalovirus (CMV) disease, whereas 12.3% of the MMF group contracted CMV (P < .0001). CMV viremia developed in 28.9% of the MZR group vs 46.9% of the MMF group (P < .0001); their peak antigen levels were 20.4 ± 44.1 and 252.8 ± 527.0 (P < .01). Furthermore, the incidence of gastrointestinal disorder, hyperlipidemia, and blood disorder was significantly lower in the MZR group than in the MMF group. The combination of high-dose MZR with CsA, basiliximab, and corticosteroids not only provides satisfactory immunosuppression but is also associated with a low incidence of CMV infection and gastrointestinal and blood disorders.

Gender and Age Analyses of NIRS/STAI Pearson Correlation Coefficients at Resting State.

According to the valence asymmetry hypothesis, the left/right asymmetry of PFC activity is correlated with specific emotional responses to mental stress and personality traits. In a previous study we measured spontaneous oscillation of oxy-Hb concentrations in the bilateral PFC at rest in normal adults employing two-channel portable NIRS and computed the laterality index at rest (LIR). We investigated the Pearson correlation coefficient between the LIR and anxiety levels evaluated by the State-Trait Anxiety Inventory (STAI) test. We found that subjects with right-dominant activity at rest showed higher STAI scores, while those with left dominant oxy-Hb changes at rest showed lower STAI scores such that the Pearson correlation coefficient between LIR and STAI was positive. This study performed Bootstrap analysis on the data and showed the following statistics of the target correlation coefficient: mean=0.4925 and lower confidence limit=0.177 with confidence level 0.05. Using the KS-test, we demonstrated that the correlation did not depend on age, whereas it did depend on gender.

Nonlinear increase of X-ray intensities from thin foils irradiated with a 200 TW femtosecond laser.

We report, for the first time, that the energy of femtosecond optical laser pulses, E, with relativistic intensities I > 10(21) W/cm(2) is efficiently converted to X-ray radiation, which is emitted by "hot" electron component in collision-less processes and heats the solid density plasma periphery. As shown by direct high-resolution spectroscopic measurements X-ray radiation from plasma periphery exhibits unusual non-linear growth ~E(4-5) of its power. The non-linear power growth occurs far earlier than the known regime when the radiation reaction dominates particle motion (RDR). Nevertheless, the radiation is shown to dominate the kinetics of the plasma periphery, changing in this regime (now labeled RDKR) the physical picture of the laser plasma interaction. Although in the experiments reported here we demonstrated by observation of KK hollow ions that X-ray intensities in the keV range exceeds ~10(17) W/cm(2), there is no theoretical limit of the radiation power. Therefore, such powerful X-ray sources can produce and probe exotic material states with high densities and multiple inner-shell electron excitations even for higher Z elements. Femtosecond laser-produced plasmas may thus provide unique ultra-bright X-ray sources, for future studies of matter in extreme conditions, material science studies, and radiography of biological systems.

Reconsideration of discrepancies between clinical and histopathological features in acute eosinophilic pneumonia.

BACKGROUND AND OBJECTIVES: Acute eosinophilic pneumonia (AEP) is a very rare condition, with only one paper published so far discussing histopathological findings at surgical biopsy. In that paper, AEP is considered to be an acute and proliferative stage of DAD accompanied by eosinophilia. However, acute respiratory distress syndrome, acute interstitial pneumonia, and acute exacerbation of idiopathic pulmonary fibrosis, which, unlike AEP are mostly life-threatening diseases, also exhibit DAD. AEP also presents with severe hypoxia but rapidly improves on treatment with corticosteroids alone, without subsequent fibrosis. In contrast, the other above-mentioned diseases with the same histopathology show greatly different clinical courses. The reasons for these differences remain unclear. METHODS: Here we investigated the histopathology of AEP in 2 surgical lung biopsy and 14 transbronchial lung biopsy cases. Additionally, we determined the presence or absence of different phases of DAD by histopathology in these AEP cases. RESULTS AND CONCLUSION: Characteristic histopathological findings of AEP consist of alveolar edema with infiltration of eosinophils and lymphocytes and edema of perivascular area and interlobular septa. The alveolar spaces showed fibrinous exudates. There were no hyaline membranes or massive intraluminal fibrosis. These histopathological findings of interstitial edema and fluid exudates are consistent with radiological findings of lung edema and can explain the rapid and complete improvement.Because AEP does not exhibit lung fibrosis histopathologically, it should not to be included in DAD which is associated with lung fibrosis.