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The use of hybrid operating rooms (HOR) for transcatheter aortic valve implantation (TAVI) has increased, so radiation exposure during procedures that use X-ray fluoroscopy is a fundamental problem not only for patients but also for surgeons and interventional cardiologists, increasing the risk of cataracts among operators. We investigated the efficacy of leaded glasses and protective sheets for ocular radiation protection.Methods and Results: Between January 2020 and February 2021 we enrolled 54 TAVI procedures using the transfemoral approach. The subjects were divided into a curtain protection group (Group C, n=20), glass protection group (Group G, n=17), and sheet protection group (Group S, n=17). The cumulative dose (CD) of the operators showed a decreasing trend in Group S compared with the other two groups. The CD normalized by dose area product (CD/DAP) of the operators was significantly reduced in Group S compared with Group C. However, Group G showed no significant difference compared with Group C. Regarding the distribution of CD/DAP, Group S had a significantly lower distribution than that in groups C and G.Protective sheets provide more stable radiation protection than conventional curtains or leaded glasses.

Although transcatheter aortic valve replacement (TAVR) has demonstrated favorable outcomes in randomized studies, there remains a sizable group of patients in whom TAVR may be futile. Characterizing the survival rate in a wide array of patients undergoing TAVR can help develop effective strategies for improving the allocation of medial resources.The aim of this study was to develop a risk model to estimate 1-year mortality after TAVR from a representative nationwide registry in Japan.The J-TVT (Japan Transcatheter Valve Therapies) registry contains complete data, including 1-year outcomes, on patients undergoing TAVR in Japan. A total of 17,655 patients underwent TAVR between 2013 and 2018. They were randomly divided into 2 groups in a 7:3 ratio to form a derivation cohort of 12,316 patients and a validation cohort of 5,339 patients. A risk model was constructed for 1-year mortality in the derivation cohort, and its discrimination and calibration were assessed in the validation cohort.The mean age of all registered patients was 84.4 years, and 68.8% were women. The mean body size area was 1.43 mA prediction model for 1-year survival following TAVR derived from a national clinical database performed well and should aid physicians managing TAVR patients.

Background Aortic root rupture is a severe complication of balloon-expandable transcatheter aortic valve replacement (TAVR). Although previous studies have revealed several risk factors for this complication, predicting this complication is occasionally difficult. Case summary A 78-year-old male patient underwent TAVR via a transfemoral approach using a 29-mm balloon-expandable valve. No recognized risk factors for aortic root rupture existed in pre-procedural multi-detector computed tomography (MDCT) analysis. However, after the valve deployment, sudden haemodynamic collapse occurred. Transoesophageal echocardiography revealed pericardial effusion, which led to an immediate diagnosis of cardiac tamponade following aortic root rupture. Following pericardial drainage via a subxiphoid approach, the haemodynamics were immediately stabilized. After 10 days of close observation, the patient was discharged on Day 39 without additional problems. He was still alive at the 6-month follow-up without sequelae. Discussion Established risk factors for aortic root rupture include >20% area oversizing, bicuspid aortic valve, small annulus (

Background: The outcome of redo transcatheter aortic valve (TAV) implantation (TAVI) is unknown for TAV structural valve degeneration (SVD). This paper reports the initial results of redo TAVI for TAV-SVD in Japanese patients. Methods and Results: Of 630 consecutive patients, 6 (1.0%) underwent redo TAVI for TAV-SVD (689-1,932 days after the first TAVI). The first TAV were 23-mm balloon-expandable valves (BEV, n=5) and a 26-mm self-expandable valve (SEV, n=1). All patients underwent multidetector computed tomography (MDCT) before redo TAVI, which showed first-TAV under-expansion (range, 19.1-21.0 mm) compared with the label size. Two BEV and 4 SEV were successfully implanted as second TAV, without moderate/severe regurgitation or 30-day mortality. One of 2 patients with a BEV-inside-BEV implantation had a high transvalvular mean pressure gradient post-procedurally (34 mmHg) and required surgical valve replacement 248 days after the redo TAVI. This, however, was unnoted in patients with SEV implantation during redo TAVI. Planned coronary artery bypass grafting was concomitantly performed in 1 patient with a small sino-tubular junction and SEV-inside-SEV implantation because of the risk of coronary malperfusion caused by the first TAV leaflets. Five of the 6 patients survived during the follow-up period (range, 285-1,503 days). Conclusions: Redo TAVI for TAV-SVD appears safe and feasible, while specific strategies based on MDCT and device selection seem important for better outcomes.

Photodecomposition and photobactericidal activities of anatase/rutile-mixed phase TiO2 nanoparticles annealed with low-temperature O2 plasma were clarified by comparing them with those annealed in ambient air. The photocatalytic activities of plasma-assisted-annealed sample greatly enhanced as compared with the untreated sample, under not only ultraviolet irradiation but also visible-light irradiation. The photocatalytic activities of air-annealed samples did not enhance under ultraviolet irradiation but enhanced under visible-light irradiation. The enhanced photocatalytic activities due to the plasma-assisted annealing (PAA) originated from the increased photoexcited carrier concentration. This enhancement was discussed from PAA-induced characteristic factors. PAA facilitated the phase transformation to anatase, contributing directly to extending the photoexcited carrier lifetime. PAA introduced more oxygen vacancies, contributing to trapping more photogenerated electrons. PAA also introduced more bridging/terminal oxygen groups adsorbed on the surface, increasing the upward band-bending, the depletion layer width at the surface, and the charge transfer from rutile to anatase. These two introductions contributed to facilitating the separation of photoexcited carriers. Furthermore, PAA reduced the aggregate size of TiO2 nanoparticles formed on the surface, contributing to increasing optical absorptions. More reactive oxygen species produced from the bridging/terminal oxygen groups by the photoexcited carriers would also enhance the photocatalytic activities.

The thermal stability, in terms of cycle and rate performances at 80 °C, and its safety related to lithium ion batteries composed of a LiFePO 4 cathode and SiO anode are investigated. Based on an STEM-EELS analysis, the SiO powder is found to have an amorphous structure, in which nanosized Si particles (Si-rich phase) are uniformly dispersed in the SiO 2 matrix (SiO 2 -rich phase). During the charge/discharge cycling, the cell exhibits a satisfactory cycle performance with a discharge capacity retention of 93.6% and a voltage retention of 93.9% at the 1500 th cycle. Also, the charge and discharge capacity retentions at 10 C are 97.5% and 94.7%, respectively, together with a limited polarization, demonstrating its high rate performance. Furthermore, a 1.16 Ah LiFePO 4 /SiO laminated cell shows negligible voltage and temperature changes during the nail penetration test. The Li concentration in the active material (Si-rich phase) is found to be almost the same as that in the SiO 2 -rich phase after the test. This high thermal stability and safety may be due to the formed layer from the SiO 2 matrix, preventing any side reaction from occurring on the Si surface and isolating the internal current path during the nail penetration.

For further penetration of lithium-ion battery, safer battery design with high energy density is required. In the case of the thermal runaway of conventional lithium-ion batteries, the reaction of electrolyte on the surface of graphite anode at higher temperature causes the gas generation with the temperature rise. Subsequently, the short circuit due to the separator meltdown leads to the oxygen release by the pyrolysis of cathode and the thermite reaction above the melting of aluminum utilized for the current collector and the cell package. The construction of novel safer battery systems with high energy density is possible through a judicious choice of each component: cathode material, electrolyte, separator, anode material, current collector and package. We develop safer battery configurations through the analysis of practical batteries using various techniques such as calorimetry and overcharge / internal short-circuit tests. In this study, we assemble 1 Ah class pouch-type full cell with lithium iron phosphate cathode and silicon oxide anode [1]. The full cell shows good charge-discharge properties even at high-rate and 100˚C (Figure 1). On the estimation, however, the electrochemical energy of both electrode active materials is only about 3% of the total thermal energy of full cell. Thus, we replace aluminum with stainless steel utilized for the current collector and package. In addition, we select a separator of heat-stable nonwoven fabric instead of polyethylene/polypropylene. The total thermal energy of full cell by the alternative separator, current collector and package is found to be reduced to 14% of the initial value. In short-circuit testing, the full cell did not show fire though heat and smoke were generated since the maximum temperature of the cell is only 52˚C. In this way, it is possible to design batteries with highly safe by considering the non-flammability of each component such as the current collector and the package as well as the separator. References [1] M. Yanagida, T. Mukai, Y. Ikeuchi, N. Yamashita, T. Sakamoto, H. Senoh and H. Tanaka, Abstract of the 60th Battery Symposium in Japan, 2B23 (2019). Figure 1

A face centered cubic (FCC) type Mg–Sc hydride (Mg0.8Sc0.2Hx phase) was prepared by an ultra-high pressure (UHP) technique generating an 8 GPa hydrogen pressure. Reversible hydrogen releasing and restoring behaviors have been observed by a differential scanning calorimeter (DSC) measurement at a 0.5 MPa hydrogen pressure. The hydrogen releasing temperature was lower by around 70 K than that of MgH2. The structural analysis using a Rietveld refinement of the synchrotron X-ray diffraction patterns indicated that the FCC phase was preserved without decomposition after the reproducible hydrogen releasing and restoring reactions.

Polypropylene (PP) film surfaces were treated using air-based nonequilibrium atmospheric pressure plasma jets generated with a twisted wires-cylindrical electrode configuration. For comparison, PP samples were also processed with Ar plasma jets. The flux of charged particles imparted to the polymer surface by the air plasma jet greatly increased with decreases in both the gas flow rate and nozzle-to-sample distance, which was not the case for the Ar plasma jet. Reducing the gas flow rate and the nozzle-to-sample distance greatly enhanced the extent to which the surface was rendered hydrophilic by the air plasma within a short treatment time of 1 min. This enhanced effect is believed to originate from a high concentration of oxygen-based functional polar groups (FPGs) containing C O/C OH and C O/C O OH bonds grafted onto the surface. The hydrophilic surfaces resulting from this process also exhibited nanopore structures. The large number of oxygen-based FPGs produced by the air plasma can be attributed primarily to oxygen radical ions impinging from the air plasma on the surface. This can further be attributed secondarily to heat-induced oxidation rather than the sticking of oxygen radicals and UV-induced oxidation from the plasma. The nanoporous structure can also be ascribed to oxidation from UV photogenerated holes.

In the development of lithium-ion batteries (LIBs), cathode materials are being further improved to achieve not only higher energy capacity but also longer cycle life. Analyzing the valence of the cathode active materials during charge and discharge cycles is one of the practical methods to understand the redox mechanism and degradation mechanism, which can help in achieving higher energy capacity and longer life. The valence has been evaluated using X-ray absorption fine structure (XAFS) measurements with a synchrotron X-ray source. To conduct in-house analyses of valence, we developed a polychromatic simultaneous wavelength dispersive X-ray fluorescence (PS-WDXRF) spectrometer, which is comprising an X-ray tube, a slit, a flat analyzing crystal, and a silicon strip detector (SSD) [1]. The X-ray dispersed by the crystal is simultaneously detected by the SSD, and the detected signals at each channel provide intensity information at corresponding energy. Because there are no moving parts in the optical setup, the spectrometer is possible to detect the chemical changes, including valence changes, of 3d transition metals with high precision. Two PS-WDXRF spectrometers were developed. One spectrometer comprises a 1280-channel SSD and a Ge (220) crystal to detect X-rays in the range around 5.38 - 6.52 keV, which is designed for manganese. Another spectrometer comprises same components with another one and the range of detecting X-ray energy is 6.27 – 7.89 keV, which is designed for cobalt and nickel. The first step was to obtain and analyze data of pressed powders of manganese oxides using the spectrometer for manganese. Thus, powders of MnO (II), Mn2O3 (III), MnO2 (IV), and KMnO4 (VII) were placed in the evacuated chamber of the experimental setup. An X-ray tube voltage of 20 kV and a current of 100 mA was applied, and the target was made from Rh and no filter was used. A 5-min measurement was repeated five times for each sample. The PS-WDXRF analysis showed that the specimens achieved clearly different peak energies which belong to more fine electron transition fluorescence lines. This means that the WDXRF has sufficient energy resolution, and the valence information is obtained by the peak energy shift derived from the chemical shift [2, 3]. The second step was to obtain and analyze data of pressed powders of cobalt oxides and nickel oxides using the spectrometer for cobalt and nickel. Thus, powders of CoO(II), LiCoO2(III), NiO(II) and LiNiO2(III) were placed in the evacuated chamber of the experimental setup. An X-ray tube voltage of 20kV and a current of 100 mA was applied, and the target was made from W and no filter was used. This experiment demonstrated the discriminability of fluorescence peak energy shift derived from the chemical shift, in spite of the worse channel resolution. These results indicate that there is a potential for valence evaluation of cathode materials in a short time with highly precise energy resolution. These spectrometers were applied to the evaluation of actual cathode active materials in LIBs which is including manganese, cobalt or nickel. Some different states of cathode materials were prepared and the valence estimation was performed using the PS-WDXRF spectrometers. The relationship between the valence result and state of charge/discharge was confirmed, which shows that the valence number of LIBs cathode material is in accordance with the reaction formula. The recent results of valence evaluation on actual cathode active materials in LIBs will be presented in detail. [1] K. Sato, A. Nishimura, M. Kaino, S. Adachi, X-Ray Spectrom. 46, 330–335 (2017). [2] J. Kawai, M. Takami, C. Satoko, Phys. Rev. Lett. 65, 2193–2196 (1990). [3] K. Sakurai, H. Eba, Nucl. Instr. Meth. Phys. Res. B199, 391–395 (2003).

To determine risk factors for systemic air embolism by percutaneous computed tomography (CT)-guided lung biopsy.This case-control study used data from 2216 percutaneous lung biopsy procedures performed over 11 years at 12 institutions in Japan. Systemic air embolism was identified by retrospective review of CT images obtained during and immediately after the procedures. To fulfill our objective, multiple variables were compared between cases and controls with univariate analyses by using Student's t test and Fisher's exact test for numerical and categorical values, respectively. Multivariate logistic regression analysis was then performed using selected variables.Ten cases of systemic air embolism and 2,206 controls were identified. Univariate analyses showed that the lesions in the lower lobe (P = 0.025) and occurrence of parenchymal hemorrhage (P = 0.019) were significant risk factors. Multivariate analysis showed that the use of a larger biopsy needle was a significant risk factor (P = 0.014).Parenchymal hemorrhage during the procedure, lesions in the lower lobe, and the use of larger biopsy needles may be risk factors for systemic air embolism by percutaneous CT-guided lung biopsy. Our findings may provide clues toward minimizing the risk of this complication.

Herein, Li-ion battery using carbon fibers instead of conventional aluminum/copper foils as the current collectors is assembled. To achieve the binder-free environment, LiMn0.97Al0.03O2-based fiber type cathode is prepared directly via a two-step strategy involving electroplating and hydrothermal method by forming active materials on the individual carbon fiber. Cu6Sn5-based fiber type anode is prepared directly via electroplating and subsequent heat treatment. The resulting LiMn0.97Al0.03O2|Cu6Sn5 Li-ion battery using carbon fiber as the current collector functions at about 3 V, with an initial capacity of 180 mAh g−1 (based on the cathode). The capacity retention is 90 % after 150 cycles. In particular, the battery using phosphate-modified LiMn0.97Al0.03O2-based fiber type electrode demonstrates a better cycling and high rate performance compared to the unmodified counterpart.

The application of radiofrequency ablation for the treatment of lung cancer by our group at Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences began in June 2001, and in the present report, we review our 10-year experience with this treatment modality at Okayama University Hospital. The local efficacy of radiofrequency ablation for the treatment of lung cancer depends on tumor size and the type of electrode used, but not on tumor type. An important factor for the prevention of local failure may be the acquisition of an adequate ablative margin. The combination of embolization and radiation therapy enhances the local efficacy. Local failure may be salvaged by repeating the radiofrequency ablation, particularly in small tumors. Survival rates after radiofrequency ablation are quite promising for patients with clinical stage I non-small cell lung cancer and pulmonary metastasis from colorectal cancer, hepatocellular carcinoma, and renal cell carcinoma. The complications caused by radiofrequency ablation can be treated conservatively in the majority of cases. However, attention should be paid to rare but serious complications. This review shows that radiofrequency ablation is a promising treatment for patients with lung cancer.

Novel quaternary hydrides Mg 7− x A x TiH 16− x (A = Li, Na, K) have been synthesized by use of an ultrahigh-pressure (UHP) technique. The Rietveld refinements for synchrotron X-ray diffraction (XRD) patterns suggest that added LiH and NaH greatly enhanced the yield of the Mg 7 TiH 16 phase. The unit cell volumes of the Mg 7− x A x TiH 16− x phases were increased with increasing the amount and the ionic radii of the alkali metals. The reversibility of the hydrogen releasing and restoring reactions was much improved by the addition of alkali metal hydrides. The reversible hydrogen storage capacities were around 3–4 wt.% for the Mg 7− x A x TiH 16− x phases on the pressure–composition isotherm (PCI) measurements. Obtained enthalpy values tend to be reduced with reducing the Δ H of the alkali metals.

The three-dimensional imaging of threading dislocations in GaN films was demonstrated using two-photon excitation photoluminescence. The threading dislocations were shown as dark lines. The spatial resolutions near the surface were about 0.32 and 3.2 µm for the in-plane and depth directions, respectively. The threading dislocations with a density less than 108 cm−2 were resolved, although the aberration induced by the refractive index mismatch was observed. The decrease in threading dislocation density was clearly observed by increasing the GaN film thickness. This can be considered a novel method for characterizing threading dislocations in GaN films without any destructive preparations.

Co 3 O 4 nanoparticles are prepared via converting cobalt oxide subunits in a cobalt metal-organic framework (Co 3 (NDC) 3 (DMF) 4 , NDC = 2,6-naphthalene- dicarboxylate; DMF = N,N′-dimethylformamide) by pyrolysis in air. The as-prepared Co 3 O 4 shows an agglomerated secondary structure with an average diameter of around 250 nm comprised of small primary Co 3 O 4 particles with a size of about 25 nm. This agglomerated structure favors the enhanced capacity, improved rate capability and prolonged cycle life as an electrode material for lithium ion batteries.

We succeeded fabricating high-output-power blue (445nm) laser diodes (LDs) with an output power of 500mW. The operating current, voltage, wall-plug efficiency of these LDs were 480mA, 4.8V, and 21.7%. Estimated lifetime of these LDs was over 30,000 hours under continuous wave operation at 25°C.

BACKGROUND Radiofrequency ablation (RFA) has become an accepted alternative for treating intrathoracic malignancies; however, the incidence and characteristics of peri- and postprocedural complications are not well described. The purpose of the study was to assess the safety and technical feasibility of percutaneous RFA in unresectable intrathoracic malignancies. METHODS Percutaneous RFA was performed in patients with intrathoracic malignancies between June 2001 and December 2004. In total, 366 tumors were treated in 137 patients in 211 sessions. All patients were nonsurgical candidates or had refused surgery. Three hundred and thirty-six lesions were subjected to RFA for the treatment of metastases and 30 lesions for primary lung carcinoma. RESULTS Although no procedural mortality occurred, 2 patients died during the course of the study because of intractable pneumothorax and massive hemoptysis (0.9%). The overall major complication rate was 17.1% (pneumothoraces requiring tube drainage in 25, pleuritis in 6, pleural effusion requiring tube drainage in 4, lung abscess in 1, and intrapulmonary hemorrhage with hemothorax in 1). Minor complications included pneumothoraces not requiring tube drainage in 108 sessions, pleural effusion without drainage in 34, hemosputum in 9, nausea and/or vomiting in 3, subcutaneous emphysema in 3, cough in 2, skin burn in 2, atelectasis in 1, and subileus in 1. High fever and/or chest pain were seen in 33.8% and 39.3% of patients, respectively. CONCLUSIONS With over 200 procedures, RFA appears to be a safe and minimally invasive option with negligible mortality and little morbidity in selected patients with unresectable intrathoracic malignancies. Cancer 2007. © 2007 American Cancer Society.

Surface plasmon (SP) coupling technique was used to enhance blue and green light emissions from InGaN/GaN quantum wells (QWs). Large enhancement of photoluminescence (PL) of both blue and green emissions was observed with silver coated samples, whereas the enhancements were not so effective for the gold coated samples. We could obtain well enhanced green emission by tuning the matching condition of QW-SP coupling with nano-grating structures at gold layers. This method should be useful to design even more efficient structures and to fabricate super bright light emitting devices.

Starting with next generation high density optical disc, commercial use of GaN based violet laser diodes (LD) has been adopted in many new fields, such as bio-medical, reprographic, exposure and etc. Recently, the lasing wavelength has broadened to cover from ultraviolet (UV) to blue-green region, which enabled other new applications. In this paper, current status of GaN based LDs in UV to Blue-green region are reported and next target is discussed.

We studied the differentiation of thyroid nodules using fine-needle aspiration biopsy (FNA) and Tl-201 scintigraphy quantitative analysis. One-hundred and thirty-one thyroid nodules were examined: 83 follicular lesions (58 benign and 25 malignant lesions) and 48 non-follicular lesions (8 benign and 40 malignant lesions). During Tl-201 scintigraphy examinations, an early and a delayed image were acquired 10 and 120 min after an intravenous injection, respectively. The T/N ratio (counts of nodular lesion/counts of contralateral normal thyroid tissue) of each image was calculated quantitatively. We assessed the ability of the Tl-201 scintigraphy and of the FNA analysis to differentiate benign and malignant lesions and determined the cut-off levels for the assays. For the follicular lesions, the area under the ROC (Receiver Operating Characteristic) curve (Az) for the Tl-201 scintigraphy data was greater than that for the FNA data. For the non-follicular lesions, the Az for the FNA data was greater than that for the Tl-201 scintigraphy data. We set cut-off levels at 1.370 for follicular lesions, and 1.070 for non-follicular lesions. The sensitivity and specificity were 76% and 82.7% for follicular lesions, and 90% and 87.5% for non-follicular lesions, respectively. The overall accuracy of the analysis was 84.0%.

The main goal of this study was to develop a method to diagnose when roots had sufficiently recovered from transplanting injury. Plant responses to light intensity, such as changes in stem diameter and vapour transpiration, were measured. The light intensity was varied by a pseudo random signal. Cross-correlation functions of light intensity and plant responses were calculated to understand the similarity of the response to the input quantitatively. The results showed that the recovery from the transplanting injury could be diagnosed when the response time lag of plant stem diameters from the top to the lower part of the plant approached the original pre-transplanting level.

InxGa1−xN multiple quantum wells (QWs) with [0001], ⟨112¯2⟩, and ⟨112¯0⟩ orientations have been fabricated by means of the regrowth technique on patterned GaN template with striped geometry, normal planes of which are (0001) and {112¯0}, on sapphire substrates. It was found that photoluminescence intensity of the {112¯2} QW is the strongest among the three QWs, and the internal quantum efficiency of the {112¯2} QW was estimated to be as large as about 40% at room temperature. The radiative recombination lifetime of the {112¯2} QW was about 0.38ns at low temperature, which was 3.8 times shorter than that of conventional [0001]-oriented InxGa1−xN QWs emitting at a similar wavelength of about 400nm. These findings strongly suggest the achievement of stronger oscillator strength owing to the suppression of piezoelectric fields.

Precise identification of recombination dynamics based on local, radiative, and nonradiative recombination has been achieved at room temperature in a blue-light-emitting InxGa1−xN/GaN single-quantum-well structure by comparing the photoluminescence (PL) spectra taken by illumination-collection mode (I-C mode) and those by illumination mode (I-mode) in scanning near-field microscopy. The PL data mapped with PL lifetimes, as well as with PL spectra, revealed that the probed area could be classified into four different regions whose dominating processes are (1) radiative recombination within a probing aperture, (2) nonradiative recombination within an aperture, (3) diffusion of photogenerated excitons/carriers out of an aperture resulting in localized luminescence, and (4) the same diffusion process as (3), but resulting in nonradiative recombination.

Spatial distribution of photoluminescence (PL) with spectral, spatial, and/or time resolution has been assessed in an InxGa1−xN single-quantum-well (SQW) structure using scanning near-field optical microscope (SNOM) under illumination-collection mode at 18 K. The near-field PL images revealed the variation of both intensity and peak energy in PL spectra according to the probing location with the scale less than a few hundredths of a nanometer. PL linewidth, the value of which was about 60 meV in macroscopic PL, was as small as 11.6 meV if the aperture size was reduced to 30 nm. Clear spatial correlation was observed between PL intensity and peak wavelength, where the regions of strong PL intensity correspond to those of long wavelength. Time-resolved SNOM–PL study showed the critical evidence that supports the model of diffusion of carriers to potential minima.