ABSTRACTContrary to the conventional belief that, in transmission electron microscopy (TEM), selective and sharp imaging of dislocation loops can be realized only by accurate tilting of a specimen ...from the condition that the symmetrical axis of incident electron beam distribution is parallel to a zone axis of the TEM specimen (on-zone condition), we demonstrate that selective dark-field (DF) imaging of dislocation loops at on-zone condition is possible with a scanning TEM (STEM) mode that uses an objective lens aperture to select a diffraction disk of interest. Diffraction-selected on-zone STEM (DsoZ-STEM) has been applied to selective DF imaging of dislocation loops with a short axis length of <2 nm in a single-crystal aluminum irradiated by argon ions and an electron beam at room temperature. It was found that a Kikuchi line enhances the contrast among the dislocation loops and the matrix of DsoZ-STEM images. DsoZ-STEM obeyed g·b invisibility criterion and showed good agreement with a typical visibility change of a dislocation line and a loop in conventional DF images with a specific pair of Formula: see textg. In addition, dislocation loops always showed much higher brightness in the inner side compared to the outer side in DsoZ-STEM images, simplifying the distinction of dislocation loops with apparently the same long-axis direction but different b. Thus, DsoZ-STEM can simplify the selective DF imaging for the determination of the number and the character of dislocation loops.
The impinging jet ventilation (IJV) system has been proposed as an air distribution strategy to provide a better thermal environment with a medium supply momentum than displacement ventilation (DV) ...system. However, no simplified prediction method that is practically applicable has been established to date. The ultimate goal of this study is to establish a calculation model to predict the vertical temperature profile in an IJV system. The authors aim to propose a one-dimensional model, where the room is divided into several control volumes. To perform this, the turbulent thermal diffusion between control volumes needs to be well understood. Therefore, a knowledge about the effect of each design factor such as the supply air velocity on the turbulent thermal diffusivity needs to be acquired through a parametric study. Computational Fluid Dynamics (CFD) is effective for this purpose. As a first step, the accuracy of CFD simulations is verified by conducting a full-scale experiment. The velocity profiles inside the impinging jet and the indoor temperatures are measured and compared with the CFD results. It is shown that the shear-stress transport k-ω model has a sufficient accuracy to analyse the target room, and an appropriate grid layout is established as well. The convection-radiation coupling CFD prediction where the external temperature is used as a boundary condition is adopted as the best method for the numerical study in this research. Finally, a parametric study on the supply air velocity is performed based on this setting and its effect on the thermal stratification is presented.
•The temperature distribution in an impinging jet ventilation (IJV) system is studied.•Based on a detailed full-scale test, accuracy of CFD prediction is studied.•An appropriate combination of turbulence model and grid to analyse IJV system is proposed.•The effect of the supply air momentum on the temperature distribution is presented using CFD.
In hospital wards, unpleasant odors from the human body and excreta are a troublesome problem that leads to a poor indoor air environment. Displacement ventilation (DV) can provide good air quality ...to the lower part of the room (the occupied zone), especially when the contaminant is combined with the plume from a heat source. Hence, it is believed that DV could be an efficient way to remove unpleasant odors from wards. However, if DV is used in a room containing a window or a poorly insulated wall, the convention airflow along the vertical surface during the cold and hot season will affect the indoor environment of the room. To investigate the influence of this downward and upward airflow on indoor air quality in a displacement-ventilated ward, full-scale experiments were conducted in an environmental chamber simulating a four-bed hospital ward. The temperature and contaminant concentration distributions were measured under various conditions regarding the temperature difference between the wall surface and room air. Consequently, downward convection airflow considerably affected the contaminant concentration in the occupied zone. As the downward airflow rate increased, the contaminant concentration in the lower part of the room also increased. Additionally, the zonal model for predicting the temperature and contaminant concentration was also validated and the calculated results corresponded well with measured contaminant concentration data.
•Displacement ventilation is proposed to solve unpleasant odor problems in wards.•Heat loss and gain from vertical surfaces cause convective airflow that affects DV.•Influence of the convective airflow on indoor environment in DV was investigated.•Results validate zonal model to predict temperature and contaminant concentration.
The evaluation of physiological and psychological states using thermal infrared images is based on the skin temperature of specific regions of interest, such as the nose, mouth, and cheeks. To ...extract the skin temperature of the region of interest, face alignment in thermal infrared images is necessary. To date, the Active Appearance Model (AAM) has been used for face alignment in thermal infrared images. However, computation using this method is costly, and it has a low real-time performance. Conversely, face alignment of visible images using Cascaded Shape Regression (CSR) has been reported to have high real-time performance. However, no studies have been reported on face alignment in thermal infrared images using CSR. Therefore, the objective of this study was to verify the speed and robustness of face alignment in thermal infrared images using CSR. The results suggest that face alignment using CSR is more robust and computationally faster than AAM.
d
-Aspartate (
d
-Asp) is a useful compound for a semisynthetic antibiotic and has potentially beneficial effects on humans. Several lactic acid bacteria (LAB) species produce
d
-Asp as a component ...of cell wall peptidoglycan. We previously isolated a LAB strain (named strain WDN19) that can extracellularly produce a large amount of
d
-Asp. Here, we show the factors that contribute to high
d
-Asp production ability. Strain WDN19 was most closely related to
Latilactobacillus curvatus.
The
d
-Asp production ability of strain WDN19 in a rich medium was 13.7-fold higher than that of
L. curvatus
DSM 20019. A major part of
d
-Asp was synthesized from
l
-Asp contained in the medium by aspartate racemase (RacD). During their cultivation, the RacD activity in strain WDN19 was higher than in strain DSM 20019, especially much higher in the early exponential growth phase because of the higher
racD
transcription and the higher activity of RacD itself of strain WDN19. In a synthetic medium, the extracellular production of
d
,
l
-Asp was observed in strain WDN19 but not in strain DSM 20019. The addition of
l-
asparagine (
l
-Asn) to the medium increased and gave
d
,
l
-Asp production in strains WDN19 and DSM 20019, respectively, suggesting
l
-Asp synthesis by
l
-asparaginase (AsnA). The
l
-Asn uptake ability of the strains was similar, but the AsnA activity in the middle exponential and early stationary growth phases and intracellular
d
,
l
-Asp was much higher in strain WDN19. In their genome sequences, only an aspartate aminotransferase gene was found among
l
-Asp-metabolizing enzymes, except for RacD, but was disrupted in strain WDN19 by transposon insertion. These observations indicated that the high
d
-Asp production ability of strain WDN19 was mainly based on high RacD and AnsA activities and
l
-Asp supply.
Key points
•
Strain WDN19 was suggested to be a strain of Latilactobacillus curvatus
.
•
Extracellular high
d
-Asp production ability was not a common feature of L. curvatus
.
•
High
d
-Asp production was due to high RacD and AnsA activities and
l
-Asp supply
.
RIKEN accelerator driven compact neutron source II (RANS-II), a neutron source that is designed to serve as a prototype of a next-generation downsized accelerator-based compact system, has been ...constructed and has successfully generated neutrons. We aim to demonstrate the system’s suitability for various applications, such as the on-site degradation diagnosis of concrete infrastructures, analysis of raw materials, and other uses.
Based on the 7Li(p,n)7Be reaction for neutron production, the major components of RANS-II include a newly developed ECR ion source, 2.5 MeV RFQ using copper plated steel as a proton accelerator along with a customized solid-state amplifier, and a thin lithium neutron production target deposited on a copper substrate deployed at the end of proton beamline. A movable collimator shielding assembly is placed to shield the neutron and gamma rays produced and extract the neutron beam for experimental purposes. Using this system, we succeeded in transporting a pulsed proton beam onto the Li target and observed neutron production at the target. RANS-II was successfully installed in a dedicated space in the neutronics engineering facility at the RIKEN Wako campus. A preliminary test was conducted to analyze the neutron source characterization using conventional dosimetry for neutrons. Results confirm the validity of the proposed design parameters of the RANS-II prototype.
•This paper describes a newly completed accelerator-based neutron source system.•The significance of developing a compact neutron source was explained.•New developments were made for the accelerator, the ion source, the amplifier, the neutron-producing target, and the shielding.•The results of pulsed neutron generation test are described.
Introduction
Zoledronic acid infusion is used to treat osteoporosis but patients, especially Japanese patients, often experience acute-phase reactions (APRs). In this multicenter, randomized, ...open-label, parallel-group study, we examined the efficacy of the most commonly used non-steroidal anti-inflammatory drug loxoprofen in Japan in reducing the incidence rate of zoledronic acid-induced APRs and body temperature, and investigated risk/protective factors for APRs in this population.
Materials and methods
Patients aged ≥ 60 years with primary osteoporosis (
n
= 368) were allocated randomly to zoledronic acid plus loxoprofen (ZOL + LOX) or zoledronic acid alone (ZOL). All patients received 5-mg zoledronic acid infusion on day 1, and patients in the ZOL + LOX group also received 120 mg and 180 mg of oral loxoprofen on days 1 and 2, respectively. Adverse events and body temperature were recorded during the 7-day observation period.
Results
The incidence rates of APRs were 34.4% (64/186 patients) and 47.8% (87/182 patients) in the ZOL + LOX and ZOL groups, respectively (
P
= 0.0109). The proportions of patients with increased body temperature (≥ 1 °C and ≥ 37.5 °C) were similar in both groups (
P
= 0.1186). Past bisphosphonate users had a significantly lower incidence rate of APRs than treatment-naïve patients (odds ratio 0.444, 95% confidence interval 0.285–0.692,
P
= 0.0003).
Conclusions
Zoledronic acid-induced APRs appeared to be suppressed by loxoprofen. Known risk/protective factors, including prior osteoporosis treatment, were applicable to Japanese patients.
Introduction
We have experienced unexpected under-correction after medial opening wedge high tibial osteotomy (MOWHTO). Although the tibia was corrected accurately, the postoperative mechanical axis ...(MA) was less than 57%. The purpose of this study was to evaluate the relationship between hindfoot alignment and postoperative lower limb alignment, and to reveal whether hindfoot alignment affects lower limb alignment after MOWHTO. Our hypothesis was that hindfoot alignment influences the postoperative MA in MOWHTO.
Materials and methods
This study was a retrospective comparative study. The study cohort comprised 43 knees in 43 patients who underwent MOWHTO and had standing long-leg anteroposterior view and hindfoot alignment view radiographs taken preoperatively and at 3 months postoperatively. To evaluate the hindfoot alignment, the absolute value of the ankle joint line orientation relative to the ground was added to the absolute value of the hindfoot angle. We defined a postoperative MA of 57–67% as acceptable correction (A group) and a MA of < 56% as under-correction (U group). The two groups were analyzed to identify factors that affected postoperative limb alignment.
Results
The preoperative hindfoot alignment angle was significantly larger in the U group than the A group. The preoperative hindfoot alignment angle was a significant predictive factor of the postoperative MA, and the cut-off value that distinguished under-correction from acceptable correction was 15.9 degrees.
Conclusion
Abnormal hindfoot alignment is one of the causes of under-correction after MOWHTO. Attention should be paid to the preoperative ankle joint line orientation relative to the ground and hindfoot angle. If the preoperative hindfoot alignment angle is ≥ 15.9 degrees, surgeons should reconsider the operative procedure and correction angle.
Level of evidence
Therapeutic level III, retrospective study.
Herein, La2O3 films are fabricated on a Si substrate without a La–Sr intermixing layer at the La2O3/Si interface using a pulsed laser deposition method. X‐ray diffraction data shows only two ...discernible peaks of the La2O3 films: hexagonal La2O3 (10‐1) and cubic La2O3 (222), indicating polycrystalline character. During film growth, the reflection high‐energy electron diffraction pattern from the La2O3 surface changes from an initial column shape to a complicated distributed dot pattern with narrow lines, suggesting possible structural property changes in the La2O3 film. The occurrence of a structural transition is confirmed by high‐resolution transmission electron microscopy (HRTEM), which exhibits a clear crystalline phase change from an initial ≈10 nm thick amorphous La2O3 film to polycrystalline La2O3 film on Si. Rutherford backscattering shows a reduced La–Si intermixing between La2O3 and Si. Furthermore, the results of X‐ray photoelectron spectroscopy atomic depth profile analysis show that observation of La‐silicate over the whole La2O3 film indicates that Si diffuses through whole thick La2O3 films forming Si‐doped La2O3 films. This study of the well‐defined structural characteristics and sharp interface of La2O3/Si will enable further understanding of high dielectric constant materials grown on Si by the introduction of advanced film growth technique.
Herein, high‐quality La2O3 films are successfully fabricated on Si substrates composed of amorphous and polycrystalline layers using a pulsed laser deposition method. X‐ray photoelectron spectroscopy (XPS) results clearly found Si through the whole La2O3 layer at around ≈14 wt%. This work employs an advanced film growth technique that can benefit progress in the Si‐based electronics industry.
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