In-situ heating-and-electron tomography for materials research: from 3D (in-situ 2D) to 4D (in-situ 3D)

In-situ observation has expanded the application of transmission electron microscopy (TEM) and has made a significant contribution to materials research and development for energy, biomedical, quantum, etc. Recent technological developments related to in-situ TEM have empowered the incorporation of three-dimensional observation, which was previously considered incompatible. In this review article, we take up heating as the most commonly used external stimulus for in-situ TEM observation and overview recent in-situ TEM studies. Then, we focus on the electron tomography (ET) and in-situ heating combined observation by introducing the authors' recent research as an example. Assuming that in-situ heating observation is expanded from two dimensions to three dimensions using a conventional TEM apparatus and a commercially available in-situ heating specimen holder, the following in-situ heating-and-ET observation procedure is proposed: (i) use a rapid heating-and-cooling function of a micro-electro-mechanical system holder; (ii) heat and cool the specimen intermittently and (iii) acquire a tilt-series dataset when the specimen heating is stopped. This procedure is not too technically challenging and can have a wide range of applications. Essential technical points for a successful 4D (space and time) observation will be discussed through reviewing the authors' example application.

Diffusion-Dominated Luminescence Dynamics of CsPbBr3 Studied Using Cathodoluminescence and Microphotoluminescence Spectroscopy

Time-resolved or time-correlation measurements using cathodoluminescence (CL) reveal the electronic and optical properties of semiconductors, such as their carrier lifetimes, at the nanoscale. However, halide perovskites, which are promising optoelectronic materials, exhibit significantly different decay dynamics in their CL and photoluminescence (PL). We conducted time-correlation CL measurements of CsPbBr3 using Hanbury Brown-Twiss interferometry and compared them with time-resolved PL. The measured CL decay time was on the order of subnanoseconds and was faster than PL decay at an excited carrier density of 2.1 × 1018 cm-3. Our experiment and analytical model revealed the CL dynamics induced by individual electron incidences, which are characterized by highly localized carrier generation followed by a rapid decrease in carrier density due to diffusion. This carrier diffusion can play a dominant role in the CL decay time for undoped semiconductors, in general, when the diffusion dynamics are faster than the carrier recombination.

In situ electron tomography for the thermally activated solid reaction of anaerobic nanoparticles

The nanoscale characterization of thermally activated solid reactions plays a pivotal role in products manufactured by nanotechnology. Recently, in situ observation in transmission electron microscopy combined with electron tomography, namely four-dimensional observation for heat treatment of nanomaterials, has attracted great interest. However, because most nanomaterials are highly reactive, i.e., oxidation during transfer and electron beam irradiation would likely cause fatal artefacts; it is challenging to perform the artifact-free four-dimensional observation. Herein, we demonstrate our development of a novel in situ three-dimensional electron microscopy technique for thermally activated solid-state reaction processes in nanoparticles (NPs). The sintering behaviour of Cu NPs was successfully visualized and analyzed in four-dimensional space-time. An advanced image processing protocol and a newly designed state-of-the-art MEMS-based heating holder enable the implementation of considerably low electron dose imaging and prevent air exposure, which is of central importance in this type of observation. The total amount of electron dose for a single set of tilt-series images was reduced to 250 e^- nm^-2, which is the lowest level for inorganic materials electron tomography experiments. This study evaluated the sintering behaviour of Cu NPs in terms of variations in neck growth and particle distance. A negative correlation between the two parameters is shown, except for the particle pair bound by neighbouring NPs. The nanoscale characteristic sintering behavior of neck growth was also captured in this study.

Nanoscale defect evaluation framework combining real-time transmission electron microscopy and integrated machine learning-particle filter estimation

Observation of dynamic processes by transmission electron microscopy (TEM) is an attractive technique to experimentally analyze materials’ nanoscale phenomena and understand the microstructure-properties relationships in nanoscale. Even if spatial and temporal resolutions of real-time TEM increase significantly, it is still difficult to say that the researchers quantitatively evaluate the dynamic behavior of defects. Images in TEM video are a two-dimensional projection of three-dimensional space phenomena, thus missing information must be existed that makes image’s uniquely accurate interpretation challenging. Therefore, even though they are still a clustering high-dimensional data and can be compressed to two-dimensional, conventional statistical methods for analyzing images may not be powerful enough to track nanoscale behavior by removing various artifacts associated with experiment; and automated and unbiased processing tools for such big-data are becoming mission-critical to discover knowledge about unforeseen behavior. We have developed a method to quantitative image analysis framework to resolve these problems, in which machine learning and particle filter estimation are uniquely combined. The quantitative and automated measurement of the dislocation velocity in an Fe-31Mn-3Al-3Si autunitic steel subjected to the tensile deformation was performed to validate the framework, and an intermittent motion of the dislocations was quantitatively analyzed. The framework is successfully classifying, identifying and tracking nanoscale objects; these are not able to be accurately implemented by the conventional mean-path based analysis.

Study of beamlets extracted from a multi-aperture and five-stage acceleration system

A beam optics study using the ITER-relevant high intense negative ion beams, such as 1 MeV, 200 A/m², has been performed experimentally and analytically using a multi-aperture and five-stage accelerator. Initially, multi-beamlets generated from this accelerator were deflected in various directions due to the magnetic field and space charge repulsion between beams and showed various divergences. These had limited the pulse length and the beam energy. Compensation methods of the beamlet deflections have worked effectively and contributed to achieving the ITER requirement, the divergence angle of <7 mrad, and the deflection angle of <1 mrad for 1 MeV beam. The beam pulse has been gradually extended from 1 to 100 s and is now going to a longer pulse based on these results. One of the remaining issues is to understand and suppress peripheral components of the beam, namely, the halo, and to reduce the local heat loads observed around the aperture edge. This halo component has been successfully distinguished from the beam core by using a newly developed beam emittance measurement system for high intense beams. By combining this measured beam emittance and the beam simulation, it was clarified for the first time that the halo components are generated in an area of 1 mm width from the aperture edge.

Verification of the Usefulness of an Assessment and Risk Control Sheet that Promotes Management of Cancer Drug Therapy

Background: Proper management of adverse events is crucial for the safe and effective implementation of anticancer drug treatment. Showa University Hospital uses our interview sheet (assessment and risk control [ARC] sheet) for the accurate evaluation of adverse events. On the day of anticancer drug treatment, a nurse conducts a face-to-face interview. As a feature of the ARC sheet, by separately describing the symptoms the day before treatment and the day of treatment and sharing the information on the medical record, it is possible to clearly determine the status of adverse events. In this study, we hypothesized that the usefulness and points for improvement of the ARC sheet would be clarified by using and evaluating a patient questionnaire.

Methods: This study included 174 patients (144 at Showa University Hospital (Hatanodai Hospital) and 30 at Showa University Koto Toyosu Hospital (Toyosu Hospital) who underwent pre-examination interviews by nurses and received cancer chemotherapy at the outpatient center of Hatanodai and Toyosu Hospital. In the questionnaire survey, the ARC sheet’s content and quality, respondents’ satisfaction, structural strengths, and points for improvement were evaluated on a five-point scale.

Results: The patient questionnaire received responses from 160 participants, including the ARC sheet use group (132 people) and the non-use group (28 people). Unlike the ARC sheet non-use group, the ARC sheet use group recognized that the sheet was useful to understand the adverse events of aphthous ulcers (p = 0.017) and dysgeusia (p = 0.006). In the satisfaction survey questionnaire, there was a high sense of security in the pre-examination interviews by nurses using the ARC sheet.

Conclusions: The ARC sheet is considered an effective tool for comprehensively evaluating adverse events. Pre-examination interviews by nurses using ARC sheets accurately determined the adverse events experienced by patients with anxiety and tension due to confrontation with physicians.

Two-dimensional echocardiographic scoring system of the left ventricular filling pressure and clinical outcomes in heart failure with preserved ejection fraction

Funding Acknowledgements

Type of funding sources: Public Institution(s). Main funding source(s): Japan Society for the Promotion of Science (JSPS)

Introduction

Elevated left ventricular (LV) filling pressure in non-decompensated state is a powerful indicator of worse clinical outcomes in heart failure regardless of LV ejection fraction. However, its detection is often challenging in heart failure with preserved ejection fraction (HFpEF).

Purpose

This study aimed to elucidate the predictive value of recently proposed echocardiographic parameter of LV filling pressure, Visually assessed time difference between the Mitral valve and Tricuspid valve opening (VMT) score in HFpEF.

Methods

We retrospectively analyzed 310 well-differentiated HFpEF patients in stable conditions. Using two-dimensional echocardiographic images, time sequence of opening of mitral valve and tricuspid valve was visually assessed in the apical four-chamber view and scored to 0 to 2 (0: tricuspid valve first, 1: simultaneous, 2: mitral valve first). When the inferior vena cava diameter was dilated, 1 point was added and VMT score was calculated as four grades from 0 to 3. Based on the previous study, VMT≥2 was regarded as a sign of elevated LV filling pressure (Figure 1). LV diastolic function was graded according to the guidelines. The primary endpoint was defined as a composite of cardiac death and heart failure hospitalisation during the two years after echocardiographic examination.

Results

During the follow-up period, 55 events (18%) occurred, including four cardiac deaths and 51 heart failure hospitalisations. Kaplan-Meier curves demonstrated that VMT≥2 (n = 54) was associated with worse outcomes compared to patients showing VMT ≤ 1 (n = 256) (log-rank test P &lt;0.001). Furthermore, VMT≥2 was associated with worse outcomes when tested in 100 HFpEF patients with atrial fibrillation (log-rank test P = 0.026) (Figure 2). In the adjusted model including age, systolic blood pressure, serum albumin level, and the LV diastolic function grading, VMT≥2 was independently associated with the primary outcome (hazard ratio: 2.23; 95% confidence interval: 1.17 to 4.24, P = 0.014). Additionally, the nested regression model showed that VMT scoring provided an incremental prognostic value over clinically relevant variables (age, sex, the plasma brain natriuretic peptide level, atrial fibrillation) and LV diastolic function grading (chi-square 10.8 vs 16.3, P = 0.035).

Conclusions

In patients with HFpEF, the VMT score was independently and incrementally associated with adverse clinical outcomes. Moreover, it discriminated worse clinical outcome even in HFpEF patients with atrial fibrillation. Abstract Figure. VMT scoring  Abstract Figure. Kaplan-Meier analysis

Pathophysiological mechanism of worsened clinical outcome by lowered left ventricular cardiac power output in heart failure

Funding Acknowledgements

Type of funding sources: None.

Background

Cardiac power output (CPO) is a measure of cardiac pumping function, and CPO during exercise is known to be a powerful prognostic marker of heart failure. Despite its prognostic significance, pathophysiological mechanism of the association between reduced CPO and worse clinical outcome is unknown. We hypothesized that reduced CPO is associated with worse outcome through the reduced exercise capacity and enhanced ventilatory response.

Methods

Cardiopulmonary exercise testing and exercise stress echocardiography were performed in consecutive 64 patients with chronic heart failure who admitted to our department for the management of heart failure [60 ± 14 years old, left ventricular (LV) ejection fraction 39 ± 16%, ischemic etiology 16%, brain natriuretic peptide 124 pg/ml (51-313)]. Peak oxygen uptake (peak VO2) and the lowest minute ventilation / carbon dioxide production ratio (VE/VCO2) were measured as a parameter of exercise tolerance and that of ventilatory response, respectively. LV ejection fraction was measured by disk summation method at peak exercise. By using Doppler images, E/e" at peak exercise was measured as a marker of LV filling pressure, and CPO normalized by LV mass was obtained as 0.222 × cardiac output × mean blood pressure / LV mass [W/100 g]. Cardiac events defined as hospitalization for heart failure, cardiac death, or implantation of a LV assist device after the examinations were recorded.

Results

CPO at rest was weakly correlated with peak VO2 (r = 0.25, p = 0.046) but not with VE/VCO2. In contrast, CPO at peak exercise was positively correlated with peak VO2 (r = 0.50, p &lt; 0.001) and inversely correlated with VE/VCO2 (r=-0.40, p = 0.002). Moreover, CPO at peak exercise determined both peak VO2 (b = 0.50) and VE/VCO2 (β=-0.54) independently of LV ejection fraction and E/e" at peak exercise. During a median follow-up period of 1211 days, 12 cardiac events were observed. Each of reduced peak VO2 (hazard ratio 0.78, 95% confidence interval 0.66-0.90) and increased VE/VCO2 (hazard ratio 1.10, 95% confidence interval 1.02-1.18) was associated with worse clinical outcome.

Conclusions

In patients with chronic heart failure, CPO during exercise was associated with prognosis of heart failure through the reduced exercise capacity and enhanced ventilatory response.

Enabling High-Performance Surfaces of Biodegradable Magnesium Alloys via Femtosecond Laser Shock Peening with Ultralow Pulse Energy

The fast degradation rate and poor wear resistance of magnesium (Mg) alloys in physiological environments have limited their potential usage as next-generation biodegradable orthopedic implant materials. In this work, femtosecond laser shock peening (fs-LSP) was successfully applied to simultaneously improve the surface mechanical, corrosion, and tribocorrosion properties of WE43 Mg alloys in blood bank buffered saline solution at body temperature. Specifically, the treated surfaces of WE43 Mg alloys via fs-LSP with ultralow pulse energy were investigated under different power densities, confining mediums, and absorbent materials. It was found that the combination of a black tape and a quartz layer gave the optimum peening effect under a power density of 28 GW/cm², which simultaneously strengthened the surface and reduced the corrosion kinetics. In addition, a rapid self-repassivation was observed in fs-LSP-treated WE43 surfaces during tribocorrosion, promising sustained corrosion resistance under mechanical loading, critical to the reliability of load-bearing implants. Finally, the subsurface microstructural evolution and residual stress development in WE43 after fs-LSP were discussed based on the results from transmission electron microscopy analysis and finite element simulations.

Unique transition of yielding mechanism and unexpected activation of deformation twinning in ultrafine grained Fe-31Mn-3Al-3Si alloy

Tensile mechanical properties of fully recrystallized TWIP steel specimens having various grain sizes (d) ranging from 0.79 μm to 85.6 μm were investigated. It was confirmed that the UFG specimens having the mean grain sizes of 1.5 μm or smaller abnormally showed discontinuous yielding characterized by a clear yield-drop while the specimens having grain sizes larger than 2.4 μm showed normal continuous yielding. In-situ synchrotron radiation XRD showed dislocation density around yield-drop in the UFG specimen quickly increased. ECCI observations revealed the nucleation of deformation twins and stacking faults from grain boundaries in the UFG specimen around yielding. Although it had been conventionally reported that the grain refinement suppresses deformation twinning in FCC metals and alloys, the number density of deformation twins in the 0.79 μm grain-sized specimen was much higher than that in the specimens with grain sizes of 4.5 μm and 15.4 μm. The unusual change of yielding behavior from continuous to discontinuous manner by grain refinement could be understood on the basis of limited number of free dislocations in each ultrafine grain. The results indicated that the scarcity of free dislocations in the recrystallized UFG specimens changed the deformation and twinning mechanisms in the TWIP steel.

A correlation between grain boundary character and deformation twin nucleation mechanism in coarse-grained high-Mn austenitic steel

In polycrystalline materials, grain boundaries are known to be a critical microstructural component controlling material’s mechanical properties, and their characters such as misorientation and crystallographic boundary planes would also influence the dislocation dynamics. Nevertheless, many of generally used mechanistic models for deformation twin nucleation in fcc metal do not take considerable care of the role of grain boundary characters. Here, we experimentally reveal that deformation twin nucleation occurs at an annealing twin (Σ3{111}) boundary in a high-Mn austenitic steel when dislocation pile-up at Σ3{111} boundary produced a local stress exceeding the twining stress, while no obvious local stress concentration was required at relatively high-energy grain boundaries such as Σ21 or Σ31. A periodic contrast reversal associated with a sequential stacking faults emission from Σ3{111} boundary was observed by in-situ transmission electron microscopy (TEM) deformation experiments, proving the successive layer-by-layer stacking fault emission was the deformation twin nucleation mechanism, different from the previously reported observations in the high-Mn steels. Since this is also true for the observed high Σ-value boundaries in this study, our observation demonstrates the practical importance of taking grain boundary characters into account to understand the deformation twin nucleation mechanism besides well-known factors such as stacking fault energy and grain size.

Towards data-driven next-generation transmission electron microscopy

Electron microscopy touches on nearly every aspect of modern life, underpinning materials development for quantum computing, energy and medicine. We discuss the open, highly integrated and data-driven microscopy architecture needed to realize transformative discoveries in the coming decade.

Presence and significance of mid-systolic notch on right ventricular outflow tract velocity envelopes in pulmonary hypertension due to heart failure

Funding Acknowledgements

Type of funding sources: None.

Background

 A mid-systolic notch (MSN) of the right ventricular outflow tract (RVOT) pulsed-wave Doppler envelope, which is recognized as a characteristic finding in pre-capillary pulmonary hypertension (PH), is often observed in heart failure (HF) patients. However, clinical significance of MSN formation in HF has not been elucidated.

Methods

 Consecutive 233 HF patients who underwent right heart catheterization and echocardiography within 24 hours were enrolled. Isolated post-capillary PH (IpcPH) was defined as mean pulmonary arterial pressure (mPAP) &gt;20 mmHg, mean pulmonary artery wedge pressure (mPAWP) &gt;15 mmHg, and pulmonary vascular resistance (PVR) &lt;3 Wood units and combined pre- and post-capillary PH (CpcPH) was as mPAP &gt;20 mmHg, mPAWP &gt;15 mmHg, and PVR ≥3 Wood units. Pulmonary arterial capacitance (PAC) was calculated as stroke volume / pulmonary arterial pulse pressure [mL/mmHg]. MSN was defined as formation of notch within first half of the RVOT pulsed-wave Doppler envelope.

Results

 Prevalence of IpcPH, CpcPH, and without PH were 87 (37%), 45 (19%), and 101 (43%), respectively and MSN was observed in 8 (9%) of IpcPH, 17 (38%) of CpcPH, and 1 (1%) of patients without PH. Among the hemodynamic and echocardiographic parameters, mPAP and PAC independently determined occurrence of MSN in all the multivariable models (Table). Interestingly, when the PH patients were dimidiated according to median PAC (3.2 mL/mmHg), 25 out of 102 PH patients (25%) with low PAC showed MSN whereas any of PH patients with high PAC did not (Figure).

Conclusion

 MSN was frequently observed in HF patients showing CpcPH. Combination of elevated pressure and reduced compliance of the pulmonary circulation could determine occurrence of MSN in HF.

Determinants of MSN occurrence Univariable analysis Multivariable analysis Model 1 Model 2 Model 3 Model 4 variables OR (95% CI) p OR (95% CI) p OR (95% CI) p OR (95% CI) p OR (95% CI) p LV ejection fraction 0.97 (0.94-0.99) 0.007 1.00 (0.96-1.03) 0.795 LV mass index 1.00 (1.00-1.02) 0.143 PAW pressure 1.13 (1.08-1.18) &lt;0.001 0.92 (0.82-1.03) 0.135 Mean PA pressure 1.14 (1.09-1.19) &lt;0.001 1.08 (1.02-1.14) 0.006 1.15 (1.04-1.27) 0.004 1.08 (1.00-1.17) 0.030 1.07 (1.01-1.14) 0.025 Mean RA pressure 1.14 (1.06-1.22) &lt;0.001 1.00 (0.90-1.11) 0.978 Pulmonary vascular resistance 1.97 (1.45-2.67) &lt;0.001 1.20 (0.88-1.63) 0.225 Pulmonary arterial capacitance 0.27 (0.15-0.48) &lt;0.001 0.49 (0.26-0.92) 0.010 0.44 (0.23-0.85) 0.004 0.47 (0.24-0.93) 0.011 0.49 (0.26-0.93) 0.011 Abstract Figure.

Simple echocardiographic scoring system to estimate left ventricular filling pressure based on visual assessment of time sequence of mitral and tricuspid valve opening

Introduction

In the presence of elevated left ventricular (LV) filling pressure, mitral valve (MV) becomes to open early and precedes tricuspid valve (TV) opening in early diastole. Accordingly, time-delay of right ventricular inflow relative to LV inflow assessed by dual Doppler system was recently reported as a parameter of LV filling pressure. We assumed that visually-assessed time-delay of TV relative to MV opening could be a simple and alternative marker of elevated LV filling pressure.

Purpose

This study aimed to elucidate the clinical usefulness of the 2-dimensional echocardiographic scoring system, Visual assessment of time-difference between Mitral and Tricuspid valve opening (VMT) score, in patients with heart failure (HF).

Methods

We analyzed 119 consecutive HF patients who underwent echocardiography and cardiac catheterization within a day. Elevated LV filling pressure was defined as mean pulmonary arterial wedge pressure (PAWP) ≥15 mmHg. LV diastolic function was graded according to the ASE/EACVI recommendations. Time sequence of opening of MV and TV was visually assessed in the apical 4-chamber view and scored to 3 grades (0: TV opening first, 1: simultaneous, 2: MV opening first). When the inferior vena cava diameter was &gt;21 mm and collapsed &lt;20% during normal respiration, 1 point was added and VMT score was calculated as 4 grades from 0 to 3. We also investigated 113 patients without worsening HF at VMT scoring for cardiac events defined as worsening HF, LV assist device implantation, or cardiac death for 1 year after the echocardiography.

Results

VMT was scored as 0 in 20 patients, 1 in 50 patients, 2 in 37 patients, and 3 in 12 patients. PAWP was elevated in patients with VMT score of 2 and 3 (0: 10±5, 1: 12±4, 2: 22±8, 3: 28±4 mmHg, ANOVA P&lt;0.001) (Figure). In overall patients, VMT≥2 predicted elevated PAWP with accuracy of 86%. When the accuracy was tested in patients with reduced (&lt;40%, HFrEF) and preserved LV ejection fraction (≥40%) respectively, the accuracy was excellent in HFrEF (96% and 77%, respectively). Importantly, VMT≥2 also had good accuracy of 82% for elevated PAWP in 33 patients in whom recommendations usually cannot grade diastolic function due to monophasic LV inflow. In the sequential Cox models, the addition of VMT score to the model including the plasma brain natriuretic peptide (BNP) level and LV diastolic grading improved the predictive power for elevated PAWP (P&lt;0.001). During the follow-up, 20 cardiac events were observed (6 worsening HF, 9 LV assist device implantation and 5 cardiac death). Kaplan-Meier analysis showed that the patients with VMT≥2 were at higher risk of cardiac events than those with VMT≤1 (log-rank test P&lt;0.001) (Figure).

Conclusions

The VMT score was a simple and accurate marker of elevated LV filling pressure and has an incremental benefit over BNP and LV diastolic function grading. Moreover, it could be a novel prognostic marker in patients with HF.

Figure 1

Funding Acknowledgement

Type of funding source: None

Ultra-Fast Electron Microscopic Imaging of Single Molecules With a Direct Electron Detection Camera and Noise Reduction

Time-resolved imaging of molecules and materials made of light elements is an emerging field of transmission electron microscopy (TEM), and the recent development of direct electron detection cameras, capable of taking as many as 1,600 fps, has potentially broadened the scope of the time-resolved TEM imaging in chemistry and nanotechnology. However, such a high frame rate reduces electron dose per frame, lowers the signal-to-noise ratio (SNR), and renders the molecular images practically invisible. Here, we examined image noise reduction to take the best advantage of fast cameras and concluded that the Chambolle total variation denoising algorithm is the method of choice, as illustrated for imaging of a molecule in the 1D hollow space of a carbon nanotube with ~1 ms time resolution. Through the systematic comparison of the performance of multiple denoising algorithms, we found that the Chambolle algorithm improves the SNR by more than an order of magnitude when applied to TEM images taken at a low electron dose as required for imaging at around 1,000 fps. Open-source code and a standalone application to apply Chambolle denoising to TEM images and video frames are available for download.

P2474Noninvasive estimation of pulmonary capillary wedge pressure by novel 3D speckle tracking echocardiography and validation study by cardiac catheterization

Background

We previously reported that pulmonary capillary wedge pressure (PCWP) was noninvasively evaluated by 2D speckle tracking echocardiography (STE). Recently, novel software was introduced to examine volume and function of left ventricular and left atrium (LA) by 3D-STE automatically.

Purpose

We sought to compare the PCWP estimated by conventional 2D-STE (2D-ePCWP) and by novel 3D-STE (3D-ePCWP), and validate those values by cardiac catheterization.

Methods

Echocardiography and catheterization were performed in 29 patients (age 72±2) (7 ischemic heart disease, 2 hypertensive heart disease, 5 dilated cardiomyopathy, 12 valvular heart disease and 3 primary pulmonary hypertension).The ePCWP (mmHg) is noninvasively obtained as 10.8 − 12.4 x Log (left atrial active emptying function/minimum volume) as we previously reported. Echocardiography was performed just before the catheterization and we analyzed the 2D and 3D data by novel off-line software. 3D data was automatically analyzed and the border settings were fixed at default (ES60, ED30) (Figure).

Results

2D-ePCWP and 3D-ePCWP had a good correlation with PCWP invasively obtained by catheterization (r=0.87 and 0.83, respectively, both p<0.001). There was an excellent correlation between 2D-ePCWP and 3D-ePCWP (r=0.94, p<0.001) and there was a good correlation between 2D-LA volume index and 3D- LA volume index (r=0.80, p<0.001). Bland-Altman analysis revealed a good agreement between 2D-ePCWP and 3D-ePCWP, and between 2D-ePCWP and 3D-ePCWP without fixed and proportional bias.

Conclusion

This study demonstrated that PCWP might be noninvasively assessed by not only 2D-STE but also 3D-STE with reasonable accuracy and 3D-STE might have utility and value in the routine clinical practice.

Toughening Cellulose: Compatibilizing Polybutadiene and Cellulose Triacetate Blends

We report the synthesis of an ABA triblock copolymer of the structure CTA-b-PB-b-CTA (CTA = cellulose triacetate and PB = polybutadiene) and its ability to compatibilize immiscible CTA/PB polymer blends. CTA-b-PB-b-CTA was synthesized via ring-opening metathesis polymerization of cyclooctadiene (COD) in the presence of CTA containing a single olefin on the reducing end. The ABA triblock copolymer was incorporated into CTA/PB blends, resulting in films that were clear, tough, and creaseable, and increases in modulus, elongation at break, and toughness were observed with addition of as little as 1 wt % compatibilizer. Scanning electron microscopy revealed well-defined PB phases in the CTA matrix that decreased in domain size as more compatibilizer was added. This work may enhance the application scope of CTA and other cellulose-derived renewable polymers.

Enhanced release of palladium and platinum from catalytic converter materials exposed to ammonia and chloride bearing solutions

The environmental levels of platinum group elements (PGEs) are steadily rising, primarily due to exhaust emissions of vehicle catalytic converter (VCC) materials containing solid PGEs. Once these VCC materials reach soil and water, the PGEs may be transported in the form of nanoparticles (dimensions 1-100 nm) or they may be mobilized by forming coordination complexes with ligands in the environment. Chloride (Cl-) and ammonia (NH3) are two ligands of particular concern due to their ubiquity as well as their potential to form the chemotherapy drug cisplatin (Pt(NH3)2Cl2) or other potentially bioactive complexes. This initial study examines the release of Pd and Pt into solutions exposed to VCC materials at pH 8 and 25 °C, using elemental analysis of metal content in post-exposure extracts. The solutions had total ammonia nitrogen concentrations (TAN, [NH4+] + [NH3]) of 0 μM, 5.56 μM, 55.6 μM and 1.13 × 105 μM (0 ppm, 0.1 ppm, 1 ppm, and 2147 ppm). The former three represent background environmental levels had a minimal effect on release. However, when combined with 1.13 × 105 μM Cl- (4000 ppm Cl-), 55.6 μM TAN induced a marked increase in metal release (∼41× for Pd). High TAN solutions induced more Pd and Pt release than equimolar NaCl solutions. Materials characterization revealed that ∼4 nm palladium-containing nanoparticles were present, spatially associated with nanoparticles of γ-Al2O3; ceria-zirconia nanoparticles were also present but did not have any metal associated with them. Platinum-containing nanoparticles were not observed.

In-situ straining and time-resolved electron tomography data acquisition in a transmission electron microscope

This paper reports the preliminary results of a new in-situ three-dimensional (3D) imaging system for observing plastic deformation behavior in a transmission electron microscope (TEM) as a directly relevant development of the recently reported straining-and-tomography holder [Sato K et al. (2015) Development of a novel straining holder for transmission electron microscopy compatible with single tilt-axis electron tomography. Microsc. 64: 369-375]. We designed an integrated system using the holder and newly developed straining and image-acquisition software and then developed an experimental procedure for in-situ straining and time-resolved electron tomography (ET) data acquisition. The software for image acquisition and 3D visualization was developed based on the commercially available ET software TEMographyTM. We achieved time-resolved 3D visualization of nanometer-scale plastic deformation behavior in a Pb-Sn alloy sample, thus demonstrating the capability of this system for potential applications in materials science.

Influence of nucleobase stoichiometry on the self-assembly of ABC triblock copolymers

ABC triblock copolymers bearing adenine- and thymine-functionalized external blocks self-assembled into long-range, ordered lamellar microphase-separated morphologies on non-patterned substrates. Intermolecular hydrogen bonding formed thymine-adenine triplets and promoted self-assembly into well-defined lamellae consisting of poly(n-butyl acrylate) soft domains and complementary nucleobase hard domains, while thymine-adenine duplets contributed to superior mechanical properties.

DEEP BIOSPHERE. Exploring deep microbial life in coal-bearing sediment down to ~2.5 km below the ocean floor

Microbial life inhabits deeply buried marine sediments, but the extent of this vast ecosystem remains poorly constrained. Here we provide evidence for the existence of microbial communities in ~40° to 60°C sediment associated with lignite coal beds at ~1.5 to 2.5 km below the seafloor in the Pacific Ocean off Japan. Microbial methanogenesis was indicated by the isotopic compositions of methane and carbon dioxide, biomarkers, cultivation data, and gas compositions. Concentrations of indigenous microbial cells below 1.5 km ranged from <10 to ~10(4) cells cm(-3). Peak concentrations occurred in lignite layers, where communities differed markedly from shallower subseafloor communities and instead resembled organotrophic communities in forest soils. This suggests that terrigenous sediments retain indigenous community members tens of millions of years after burial in the seabed.

Development of a novel straining holder for transmission electron microscopy compatible with single tilt-axis electron tomography

We have developed a newly designed straining specimen holder for in situ transmission electron microscopy (TEM) compatible with high-angle single tilt-axis electron tomography. The holder can deform a TEM specimen under tensile stress with the strain rate between 1.5 × 10(-6) and 5.2 × 10(-3) s(-1). We have also confirmed that the maximum tilt angle of the specimen holder reaches ±60° with a rectangular shape aluminum specimen. The new specimen holder, termed as 'straining and tomography holder', will have wide range potential applications in materials science.

The effects of posture on the ventilatory responses during exercise

This study was undertaken to evaluate the postural effect on ventilatory responses during both supine and sitting exercise. Seven healthy men performed two exercise tests utilizing the ramp protocol (20 watts/min) with a cycle ergometer in each position. The results were as follows: The oxygen uptake and the oxygen pulse measured at 180 watts and at anaerobic threshold in the sitting were significantly higher compared with those in the supine position. The average of carbon-dioxide output, minute ventilation and tidal volume at lower exercise intensities showed higher values in the sitting compared with those in the supine position, whereas there were no significant differences for respiratory rate. There was significant difference in the slope of the minute ventilation to carbon-dioxide output plot between sitting and supine position. In conclusion, the higher minute ventilation in the sitting position was mainly performed by higher tidal volume which may counteract the effects of an increase in physiological dead space. The lower slope of the minute ventilation to carbon-dioxide output plot which shows more effective ventilation in the supine position may be due to decreased physiological dead space and higher diffusion capacity.

Cardiopulmonary responses at various angles of cycle backrest inclination

The purpose of this study was to evaluate cardiopulmonary responses during submaximal cycle exercise at various angles of backrest inclination. Ten healthy Japanese men of mean age 25.9 yrs, height 170.6 cm, and body mass 66.1 kg, performed cycle exercises at a constant workload which reached the anaerobic threshold, at 20 degrees, 40 degrees, and 60 degrees of backrest inclination from the vertical plane, but the angle between the seat and back rest was kept at 110 degrees. The results were as follows: 1) Both cardiac output and stroke volume showed a higher value at the resting control state and during exercise as the backrest angle increased. 2) Oxygen consumption, carbon dioxide output, heart rate, gas exchange ratio, and oxygen pulse were not affected by the angle of backrest inclination. 3) Tidal volume at 20 degrees of backrest inclination was higher than at 60 degrees. 4) No significant differences were found in minute ventilation between each backrest angle. These findings suggest that changes in the backrest angle significantly alter cardiopulmonary parameters at rest and during exercise; in particular, an angle difference of 40 degrees may be enough to alter tidal volume, cardiac output and stroke volume, but not the minute ventilation.

Integrated approaches of x-ray absorption spectroscopic and electron microscopic techniques on zinc speciation and characterization in a final sewage sludge product

Integration of complementary techniques can be powerful for the investigation of metal speciation and characterization in complex and heterogeneous environmental samples, such as sewage sludge products. In the present study, we combined analytical transmission electron microscopy (TEM)-based techniques with X-ray absorption spectroscopy (XAS) to identify and characterize nanocrystalline zinc sulfide (ZnS), considered to be the dominant Zn-containing phase in the final stage of sewage sludge material of a full-scale municipal wastewater treatment plant. We also developed sample preparation procedures to preserve the organic and sulfur-rich nature of sewage sludge matrices for microscopic and spectroscopic analyses. Analytical TEM results indicate individual ZnS nanocrystals to be in the size range of 2.5 to 7.5 nm in diameter, forming aggregates of a few hundred nanometers. Observed lattice spacings match sphalerite. The ratio of S to Zn for the ZnS nanocrystals is estimated to be 1.4, suggesting that S is present in excess. The XAS results on the Zn speciation in the bulk sludge material also support the TEM observation that approximately 80% of the total Zn has the local structure of a 3-nm ZnS nanoparticle reference material. Because sewage sludge is frequently used as a soil amendment on agricultural lands, future studies that investigate the oxidative dissolution rate of ZnS nanoparticles as a function of size and aggregation state and the change of Zn speciation during post sludge-processing and soil residency are warranted to help determine the bioavailability of sludge-born Zn in the soil environment.

Abiotic reductive immobilization of U(VI) by biogenic mackinawite

During subsurface bioremediation of uranium-contaminated sites, indigenous metal and sulfate-reducing bacteria may utilize a variety of electron acceptors, including ferric iron and sulfate that could lead to the formation of various biogenic minerals in situ. Sulfides, as well as structural and adsorbed Fe(II) associated with biogenic Fe(II)-sulfide phases, can potentially catalyze abiotic U(VI) reduction via direct electron transfer processes. In the present work, the propensity of biogenic mackinawite (Fe 1+x S, x = 0 to 0.11) to reduce U(VI) abiotically was investigated. The biogenic mackinawite produced by Shewanella putrefaciens strain CN32 was characterized by employing a suite of analytical techniques including TEM, SEM, XAS, and Mössbauer analyses. Nanoscale and bulk analyses (microscopic and spectroscopic techniques, respectively) of biogenic mackinawite after exposure to U(VI) indicate the formation of nanoparticulate UO2. This study suggests the relevance of sulfide-bearing biogenic minerals in mediating abiotic U(VI) reduction, an alternative pathway in addition to direct enzymatic U(VI) reduction.

Three-dimensional characterization of iron oxide (α-Fe2O3) nanoparticles: application of a compressed sensing inspired reconstruction algorithm to electron tomography

In this article, we demonstrate the application of a new compressed sensing three-dimensional reconstruction algorithm for electron tomography that increases the accuracy of morphological characterization of nanostructured materials such as nanocrystalline iron oxide particles. A powerful feature of the algorithm is an anisotropic total variation norm for the L1 minimization during algebraic reconstruction that effectively reduces the elongation artifacts caused by limited angle sampling during electron tomography. The algorithm provides faithful morphologies that have not been feasible with existing techniques.

A software tool for automatic analysis of selected area diffraction patterns within Digital Micrograph™

A software package "SADP Tools" is developed as a complementary diffraction pattern analysis tool. The core program, called AutoSADP, is designed to facilitate automated measurements of d-spacing and interplaner angles from TEM selected area diffraction patterns (SADPs) of single crystals. The software uses iterative cross correlations to locate the forward scattered beam position and to find the coordinates of the diffraction spots. The newly developed algorithm is suitable for fully automated analysis and it works well with asymmetric diffraction patterns, off-zone axis patterns, patterns with streaks, and noisy patterns such as Fast Fourier transforms of high-resolution images. The AutoSADP tool runs as a macro for the Digital Micrograph program and can determine d-spacing values and interplanar angles based on the pixel ratio with an accuracy of better than about 2%.

Molecular characterisation of the quinolone resistance-determining region (QRDR) of the parC gene locus in viridans-group streptococci

Forty-eight isolates of viridans-group streptococci (VGS) from adults and children in the community are examined for their resistance to ciprofloxacin phenotypically by determination of the minimum inhibitory concentration (MIC). In addition, the parC gene locus is amplified and sequenced in all isolates and mutations noted. Overall, 44 VGS organisms were found to be susceptible to ciprofloxacin by the broth microdilution method, and the remaining four strains had intermediate susceptibility. Reduced MICs were observed with intermediate strains when reserpine was added to the broth, inhibiting any efflux activity. Overall, the effect of adding reserpine to the broth medium was to add one doubling dilution to the MIC in the case of Streptococcus mitis, S. oralis and S. salivarius, as well as to increase the MIC by two doubling dilutions in two of the three S. parasanguinis isolates. Amino acid sequence analysis of the quinolone resistance-determining region (QRDR) of the parC gene locus showed good correlation to the phenotypic resistance to ciprofloxacin, where no confirmed mutation conferring quinolone resistance was found. Eleven amino acid positions showed discordance with S. pneumoniae R6 and eight (S52, F55, S58, N91, E135, K137, F141 and S167) were common in the VGS species examined. In addition, minor substitutions were found at three positions (D51, T54 and V86). In conclusion, this study demonstrates the low occurrence of ciprofloxacin resistance in a population of VGS isolated from the community. In addition, several silent mutations were noted in VGS organisms without any increase in MIC against ciprofloxacin.

[Pleomorphic carcinoma of the lung; report of a case]

A 83-year-old male was referred to our hospital for further examination of abnormal shadow on chest radiography. Chest computed tomography (CT) showed a tumor mass in his right lung. Bronchoscopy brushing cytology revealed non-small cell lung carcinoma and right middle lobectomy was performed. Histological findings showed large cell carcinoma comprised of spindle cell component, finally diagnosing as pleomorphic carcinoma of the lung. Although he was diagnosed as pT2N0M0 (stage IA) after the operation, massive liver metastasis was found 7 months later. We report this case with references to the literatures on pleomorphic carcinoma of the lung.

Molecular analysis and characterisation of the full-length flagellin C gene (flaC) from Campylobacter lari

A degenerate polymerase chain reaction (PCR) primer pair (f-ClflaC/r-ClflaC) was constructed in silico to amplify flaC and its adjacent genetic loci from Campylobacter lari isolates. Approximately 1.45 kbp amplicons, including the sequences encoding the flaC structural gene of 750 bp, putative promoter, rho-independent intrinsic terminator regions and partial sequences of two putative open reading frames (ORFs), immediately upstream and downstream of the gene, were identified in 16 C. lari isolates (four urease-negative [UN] C. lari; 12 urease-positive thermophilic campylobacters [UPTC)]). All 16 flaC structural genes commenced with an ATG start codon and terminated with a TAA stop codon and probable ribosome-binding sites were identified in all 16 isolates. These probably indicate a monocistronic operon structure for the flaC gene in C. lari isolates. In addition, the putative flaC gene ORFs were deduced to be similar in 747 bp among all 26 thermophilic Campylobacter isolates examined, resulting in a similar calculated molecular weight of approximately 26.6-26.9 kDa. The flaC from C. lari was different from the flaA-like sequence and the shorter flaA of UPTC isolates found previously. Reverse transcription PCR and Northern blot hybridisation analyses identified flaC transcription in C. lari cells. The transcription initiation site for the flaC gene was also determined by primer extension analysis. A dendrogram constructed, based on the nucleotide sequence information of flaC from 17 C. lari isolates, demonstrated that the C. lari isolates were genetically variable and formed two minor clusters for UN C. lari and UPTC.

Discovery and characterization of silver sulfide nanoparticles in final sewage sludge products

Nanosized silver sulfide (α-Ag(2)S) particles were identified in the final stage sewage sludge materials of a full-scale municipal wastewater treatment plant using analytical high-resolution transmission electron microscopy. The Ag(2)S nanocrystals are in the size range of 5-20 nm with ellipsoidal shape, and they form very small, loosely packed aggregates. Some of the Ag(2)S nanoparticles (NPs) have excess S on the surface of the sulfide minerals under S-rich environments, resulting in a ratio of Ag to S close to 1. Considering the current extensive production of Ag NPs and their widespread use in consumer products, it is likely that they are entering wastewater streams and the treatment facilities that process this water. This study suggests that in a reduced, S-rich environment, such as the sedimentation processes during wastewater treatment, nanosized silver sulfides are being formed. This field-scale study provides for the first time nanoparticle-level information of the Ag(2)S present in sewage sludge products, and further suggests the role of wastewater treatment processes on transformation of Ag nanoparticles and ionic Ag potentially released from them.

Influence of size and aggregation on the reactivity of an environmentally and industrially relevant nanomaterial (PbS)

Rarely observed nanoparticle dissolution rate data have been collected and explained for an environmentally and industrially relevant nanomaterial (PbS, the mineral galena) as a function of its particle size and aggregation state using high-resolution transmission electron microscopy (HRTEM) and solution analysis. Under identical anoxic acidic conditions (pH 3 HCl), it has been determined that the dissolution rate of PbS galena varies by at least 1 order of magnitude simply as a function of particle size, and also due to the aggregation state of the particles (dissolution rates measured are 4.4 x 10(-9) mol m(-2) s(-1) for dispersed 14 nm nanocrystals; 7.7 x 10(-10) mol m(-2) s(-1) for dispersed 3.1 microm microcrystals; and 4.7 x 10(-10) mol m(-2) s(-1) for aggregated 14 nm nanocrystals). The dissolution rate difference between galena microparticles and nanoparticles is due to differences in nanotopography and the crystallographic faces present. Aggregate vs. dispersed dissolution rates are related to transport inhibition in the observed highly confined spaces between densely packed, aggregated nanocrystals, where self-diffusion coefficients of water and ions decrease dramatically. This study shows that factors at the nanometer scale significantly influence the release rate of aqueous, highly toxic and bioavailable Pb in natural or industrial environments during galena dissolution.

[Pleomorphic carcinoma of the lung with idiopathic interstitial pneumonia; report of a case]

A 69-year-old man was referred to our hospital for further examination of the abnormal shadow on chest radiography. Chest computed tomography (CT) showed a tumor mass, 4 cm in size, in his right lung (S6) and interstitial pneumonia in the surrounding lung parenchyma Bronchoscopic brushing cytology revealed squamous cell carcinoma cells. Right lower and middle lobectomy was performed due to the metastasis to interlober lymph node. Histological findings showed squamous cell carcinoma comprised of spindle cell component, and there were also fibroblastic foci and fibroid thickness in the interstitium. Therefore he was diagnosed as pleomorphic carcinoma and usual interstitial pneumonia (UIP). About 7 months after the operation, the patient died of mainly multiple bone metastases. Pleomorphic carcinoma with UIP is very rare, so we report this case with references to the literatures.

Effect of angiotensin-converting enzyme gene polymorphism on left ventricular remodeling after anteroseptal infarction

BACKGROUND AND HYPOTHESIS

Genetic influence on cardiac remodeling is uncertain. The purpose of this study is to determine the effects of polymorphism of the angiotensin-converting enzyme (ACE) gene on cardiac remodeling after myocardial infarction.

METHODS

The subjects were 43 patients with old anteroseptal myocardial infarction. Based on the polymorphism of the ACE gene, they were classified into a deletion group of 25 patients (D/D genotype in 4 and D/I genotype in 21) and an insertion group of 18 patients (all I/I genotype). Echocardiograms were used to determine left ventricular end-diastolic and end-systolic diameters, interventricular septal and posterior wall thicknesses, left ventricular mass, left atrial diameter, and left ventricular ejection fraction. Blood concentrations of atrial and brain natriuretic peptide were also measured.

RESULTS

Left ventricular end-systolic and end-diastolic dimensions, left ventricular mass, and levels of both atrial and brain natriuretic peptide were significantly higher in the deletion group. In contrast, septal thickness, posterior wall thickness, and ejection fraction showed no differences between the two groups.

CONCLUSIONS

In patients with old anteroseptal infarction, ACE gene polymorphism of the D/D and D/I genotypes has a stronger influence on left ventricular remodeling than polymorphism of the I/I genotype.

Influence of angiotensin-converting enzyme gene polymorphism on development of athlete's heart

BACKGROUND AND HYPOTHESIS

Genetic influence on development of athlete's heart is uncertain. This study investigated whether angiotensin-converting enzyme (ACE) gene polymorphism influenced development of athlete's heart.

METHODS

Forty-three participants in a 100-km ultramarathon were classified on the basis of ACE gene polymorphism into a deletion group (n = 26) and an insertion group (n = 17). Echocardiograms were recorded to determine left ventricular end-diastolic and end-systolic diameters, interventricular septal thickness, left ventricular posterior wall thickness, left ventricular mass, and ejection fraction.

RESULTS

Left ventricular end-diastolic diameter (65.5 +/- 4.0 mm) and left ventricular mass (369.5 +/- 73.9 g) were significantly larger in the subjects with deletion than in those with insertion (57.4 +/- 4.2 mm, 306.5 +/- 93.7 g). However, no significant differences in the other parameters were noted.

CONCLUSIONS

In long-distance runners, ACE gene polymorphism of the D/D and D/I genotypes has a stronger influence on left ventricular hypertrophy than polymorphism of the I/I genotype.