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While low‐resolution climate models at present struggle to appropriately simulate convectively coupled large‐scale atmospheric disturbances such as equatorial Kelvin waves (EKWs), superparameterization helps better reproduce such phenomena. To evaluate such model differences based on physical mechanisms, a linearized theoretical framework of convectively coupled EKWs was developed in a form readily applicable to model evaluation by allowing background stability and diabatic heating to have arbitrary vertical profiles rather than assuming simplified ones. A system of linearized equations of convection‐coupled gravity waves was derived as a two‐dimensional model of the convectively coupled EKWs. In this work, the basic states are taken from observations, CTL‐MIROC and SP‐MIROC experiments introduced in Part 1. The tendency of convectively coupled gravity waves to grow faster under top‐heavy heating is confirmed for realistic stratification profiles, as found in previous studies under constant stratifications. A comparison of linear unstable solutions with basic states taken from SP‐MIROC and CTL‐MIROC shows that the top‐heavy heating profile in SP‐MIROC largely contributes to the enhancement of the EKW‐like unstable modes, while subtle differences of stratification profiles considerably affect EKW behaviors. The bottom‐heavy heating bias in the CTL‐MIROC likely originates from insufficient modeling of subgrid stratiform precipitation in tropical organized systems. It is desirable to incorporate such stratiform components in cumulus parameterizations to achieve better EKW reproducibility. Plain Language Summary: Present global climate models (GCMs) cannot resolve small‐scale cumulus convection. Hence, they cannot reproduce sufficient amplitudes of convectively coupled large‐scale atmospheric disturbances such as the equatorial Kelvin wave (EKW). In contrast, high‐resolution models that explicitly simulate cumulus convection can reproduce these disturbances better. In this study, a linearized theoretical framework of the convectively coupled EKW was developed to interpret and evaluate model behavior. Using this framework, EKWs simulated by different models were compared based on their physical mechanisms. The basic states were taken from observations and MIROC simulations introduced in Part 1. The tendency of EKWs to grow under a top‐heavy heating condition was confirmed under realistic stratification profiles as found in previous studies under constant stratifications. A comparison of linear unstable solutions with the basic states taken from the MIROC simulations showed that the heating altitude is the most important factor for enhancing the EKW‐like unstable modes, while stratification profiles can sometimes considerably affect EKW growth. Bottom‐heavy heating bias in the conventional MIROC likely originates from insufficient parameterization of organized precipitating systems in the tropics. It is desirable to incorporate such stratiform components in the cumulus parameterization to achieve better EKW reproducibility. Key Points: A linearized model of the EKW is derived in a form readily applicable to evaluation of numerical simulationsSuperparameterized MIROC enhanced EKW amplitudes through top‐heavy heating profilesTo improve EKW reproducibility, GCMs need better representation of tropical stratiform precipitation [ABSTRACT FROM AUTHOR]

The potential scope of superparameterization (SP) was extended to higher resolutions of the global climate model (GCM) component by devising a technique called blockwise coupling. In this method, a horizontal average of multiple GCM columns, instead of one, is coupled to a cloud‐resolving model (CRM) domain. This enables SP‐GCMs to reduce the computational cost drastically, enabling higher‐resolution GCMs to be superparameterized. A blockwise‐coupled SP‐GCM called SP‐MIROC was implemented by coupling the climate model MIROC6 to the CRM SCALE‐RM. The 4 × 4‐bundled SP‐MIROC successfully reproduced horizontal patterns and frequency distributions of precipitation and realistic amplitudes of equatorial Kelvin waves (EKWs), which were underestimated in the standard MIROC6. As discussed in Yamazaki and Miura (2024b, https://doi.org/10.1029/2023MS003837) of this study, the amplitude boost of EKWs was enabled by a top‐heavy heating in SP‐MIROC. Comparison of power spectra between the 4 × 4‐bundled SP‐MIROC and nonbundled SP‐MIROC indicated that the effective resolution of dynamic variables was not degraded by the blockwise technique. Rather, spectra in the 4 × 4‐bundled SP‐MIROC were more realistic than those in the nonbundled SP‐MIROC. Although the 4 × 4‐bundling limits convective coupling in the smallest GCM scale, it could offer the best match of resolutions between the GCM‐handled dynamics and SP‐derived physics because the effective resolution of the dynamics is lower than the nominal grid spacing. Plain Language Summary: Superparameterization is a technique to explicitly simulate subgrid clouds in low‐resolution global climate models (GCMs) by coupling small domains of a high‐resolution cloud‐resolving model (CRM). This study expands the superparameterization technique by proposing and verifying blockwise coupling, in which a CRM domain is coupled to an average of multiple GCM columns; in contrast, the existing superparameterized (SP) models employ one‐to‐one coupling between a CRM and a GCM column. We implemented a SP‐GCM by coupling the climate model MIROC6 and the SCALE‐RM CRM with 4 × 4‐to‐one blockwise coupling. Multiple benefits in existing SP‐GCMs are reproduced in the simulation results of the blockwise‐coupled SP‐MIROC. Furthermore, 4 × 4‐bundled SP‐MIROC outperformed the one‐to‐one SP‐MIROC in terms of reproducing realistic zonal spectra. Blockwise coupling will drastically reduce computational costs, making superparameterization in higher‐resolution GCMs affordable. Key Points: A superparameterized version of the climate model MIROC6 named superparameterized (SP)‐MIROC was developedComputational cost is reduced by coupling a cloud‐resolving model domain to a block of multiple global climate model columns, instead of oneBlockwise‐coupled SP‐MIROC reproduced most benefits of SP without losing the effective resolution of dynamic variables [ABSTRACT FROM AUTHOR]

To evaluate ethiodised oil retention of transarterial embolisation using ethiodised oil (ethiodised oil marking) before computed tomography (CT)-guided percutaneous cryoablation (PCA) according to renal cell carcinoma (RCC) subtype. Ethiodised oil marking was performed 1–3 days before PCA in 99 patients with 99 RCCs from 2016 to 2020. Ethiodised oil retention on CT images was evaluated retrospectively and CT attenuation values in the tumour were measured. Regions of interest (ROI) were placed on the tumours to calculate: average (ROI-average), maximal (ROI-max), minimum (ROI-min), and standard deviation (ROI-SD). Qualitative scores comprising a five-point scale (5, excellent; 1, poor) were evaluated for the retention scores (RS) of ethiodised oil in the tumour (ethiodised oil-RS) and the visualisation scores (VS) of the boundary between the tumour and renal parenchyma (boundary-VS). The histological subtypes comprised clear cell (ccRCC; n= 85), papillary (pRCC; n= 6), and chromophobe/oncocytoma renal cell carcinoma (chrRCC; n= 8). The mean ROI-average, ROI-max, and ROI-SD were significantly higher in ccRCCs than in chrRCCs and pRCCs (p< 0.05). The mean ethiodised oil-RS was significantly lower in pRCCs than in ccRCCs (p =0.039), and the mean boundary-VS was >4 in all subtypes. Even with poor intratumour ethiodised oil retention (n= 6), sufficient boundary-VS was obtained due to "inverted marking." All PCA procedures were completed without additional intravenous contrast material injection at the time of PCA. Regardless of the tumour subtypes, ethiodised oil marking aids in visualising the boundary between the tumour and parenchyma on non-contrast CT in PCA. • Ethiodized oil marking is useful in cryoablation for renal cell carcinomas. • The ethiodized oil retention patterns depend on subtypes of the tumor. • Ethiodized oil marking aids in good visibility regardless of tumor subtype. [ABSTRACT FROM AUTHOR]

In recent years, to prevent accidents and disaster are desired by implementing maintenance and management of facilities, such as conducting periodic inspections with appropriate frequency at plants. However, because the dangerous materials such as flammable gas and explosives is used in a plant, and there are many dangerous places in a plant such as high-temperature environment and high places and narrow spaces, it is desirable to use a remote-controlled robot for safety work and short inspections. Against this background, the Disaster Robotics Category-Plant Disaster Prevention Challenge was held in Japan at the World Robot Summit 2018. Our team was ranked 3rd in this competition, because our strategy of 'inspection and investigation in cooperation with UGV and UAV' was effective. In this paper, the competition contents of World Robot Summit 2018 and the robot inspection system that we are studying are explained. And what kind of strategy was challenged and result for these given competition tasks by using our robot system are introduced. And the lessons learned such as advantages and issues in UGV and UAV collaboration work at this competition are described for evaluate a robot investigation system for disaster response and inspection work at plants. [ABSTRACT FROM AUTHOR]

This study introduces a novel diagnostic method to assess tropical atmosphere‐ocean coupling, using a two‐dimensional plane defined by the 90‐day high‐pass‐filtered sea surface temperature (SST) and column water vapor (CWV). The method was applied to reanalysis data and high‐resolution coupled atmosphere‐ocean simulation data. In the Indo–Pacific warm pool region, the phase relationship between SST and CWV remained consistent across both reanalysis and simulation data sets. However, differences in the temporal evolution of these variables were observed in the central Pacific region. The heat budget analysis results indicate that the differences between the two data sets in the central Pacific are related to variations in the effects of atmospheric disturbances on SST. This study demonstrates the potential of our novel diagnostic method for evaluating atmosphere–ocean coupling in climate models. Plain Language Summary: Weather disturbances in the tropics develop from the interaction between the ocean and the atmosphere. We can use climate models to investigate the impact of this interaction, but we need other methods to evaluate the interaction itself. In this study, we develop a new way to understand how the atmosphere and the ocean interact in the tropics. We achieve this by focusing on changes over time in the sea surface temperature and the amount of water vapor in the air. We found that these changes happen at different rates in different regions of the ocean. We also found that a climate model failed to capture these changes in some regions. Our new method improves our understanding of the atmosphere and ocean interaction and teaches us how to improve climate models. Key Points: A novel analysis method was developed to illustrate regional differences in the atmosphere‐ocean coupling across tropical oceansThe application of this diagnostic method to the reanalysis and coupled model data revealed differences in the central Pacific regionThrough heat budget analysis, we proposed distinct processes by which atmospheric disturbances change the sea surface temperatures [ABSTRACT FROM AUTHOR]

Fractionated stereotactic radiotherapy (SRT) has been applied to large brain metastases to reduce the risk of radiation necrosis. For fractionated SRT, potential of interfractional tumor changes during the treatment period, such as tumor size, shape, and geometry, must be considered to improve the tumor local control. Our center performs adaptive re-planning for large brain metastases based on repeat MRI verification with a contrast agent in the middle of the treatment period. Purpose of this study is to evaluate the dosimetric impact of the changes in tumor size, shape, and geometry on the doses to the targets and normal brain in patients with brain metastases undergoing fractionated SRT. Fifteen solitary large intracranial metastatic lesions treated with fractionated SRT were investigated. Standardized planning MRI (MRI-1) and repeat verification MRI (MRI-2) were performed during the middle of the irradiation period. The GTV on the MRI-1 and MRI-2 scans was contoured by the same oncologist. The PTV was created by adding an isotropic margin of 1 mm from the GTV in all directions. Volumetric modulated arc therapy (VMAT) with beam energies of 6 MV (flattening filter-free mode) was used and plans were normalized such that PTV D 95% or D 98% was equal to the prescribed dose. Beam configuration and intensity on the initial VMAT plan were used to evaluate the dose to the tumor and the normal brain on MRI-2. We evaluated the impact of D 98% on the GTV using the plans on the MRI-1 and MRI-2 scans. For the normal brain, the V 90% , V 80% , and V 50% were investigated. The median GTV changed from 9.8 cc (range of 3.2–33.0 cc) to 9.7 cc (range of 2.8–36.5 cc) (p = 0.482). Three and four tumors exhibited volume shrinkage and enlargement changes of >10%. Five tumors exhibited volume shrinkage and enlargement changes of <10%. Three tumors showed no volume changes. Of the 15 large brain metastases, 12 tumors required treatment plan modification. The dosimetric parameters of the GTV, PTV, and normal brain did not significantly differ between the MRI-1 and MRI-2 scans. Regarding the tumor dose, the D 98% to the GTV increased in patients with tumor shrinkage because of dose inhomogeneity and decreased in patients with tumor enlargement. The V 90% , V 80% , and V 50% increase with decreasing tumor volumes and were linearly related to the tumor volume difference, with a coefficient of determination of 0.97, 0.98, and 0.97, respectively. Our study demonstrated the usefulness of repeat verification MRI for adaptive radiotherapy in the middle of the treatment period due to changes in tumor size, shape, and geometry in patients with brain metastases. Repeated MRI should be considered to evaluate the dose to the target and normal brain, which improves tumor local control and reduces brain necrosis, to reduce the magnitude of underdosing to the target or overdosing to the normal brain during the treatment period. [ABSTRACT FROM AUTHOR]

Two-dimensional sample-spinning NMR techniques for separately obtaining heteronuclear dipolar powder patterns of chemically distinct nuclei are proposed, which involve switching the spinning axis on and off the magic angle. Procedures for the computation of dipolar spectra obtained by this method are described, and various features of such spectra are discussed using simulated spectra. Practical applications of this method are demonstrated with 13C spectra of calcium formate, β-quinol-methanol clathrate, and urea-trans-4-octene clathrate, providing information on the absolute sign and magnitude of the indirect dipolar couplings, 13C–1H distances, and dynamics of trapped molecules in clathrates. [ABSTRACT FROM AUTHOR]

Dilute-spin spectra under decoupling between abundant spins and slow sample spinning at general angles are discussed, and experimentally observed with an example of calcium formate. Spectra obtained at off-magic angles break up into a train of characteristic patterns different in shape from each other. The center pattern was found to be especially sensitive to the mutual orientation between the chemical shift and dipolar coupling tensors. Each sideband observed at the magic angle shows splitting due to the 13C–1H indirect coupling. The absolute sign of the coupling constant is determined to be positive from the J-split sideband pattern. [ABSTRACT FROM AUTHOR]

Presents a study that investigated the sequence of cobalt silicide phase formation in cobalt/amorphous-silicon multilayer thin films. Formation of silicides; Analysis of the differential scanning calorimetry traces for multilayer films with atomic concentration ratios of 2CO:1Si; Activation energies of the phase transformations in cobalt/amorphous-silicon.

Commercially pure Ti grade 2 was multi-directionally forged (MDFed) at room temperature. MDFing could be successfully carried out without any cracking to a cumulative strain of ΣΔε = 2.0. Ultrafine-grained (UFGed) structure gradually developed with increasing cumulative strain mainly by mechanical twinning and kinking. An average grain size of approximately 400 nm was attained. The mechanical properties were drastically modified by the grain refinement and a superior balance of tensile strength and ductility, 710 MPa and 21%, was achieved. Additional cold rolling of the UFGed Ti possessed further better mechanical properties of 930 MPa tensile strength and 19% ductility. [ABSTRACT FROM AUTHOR]

Stainless steels were cold rolled to 92% reduction. The microstructure developed in a stable austenitic stainless steel was complicated heterogeneous nanostructure composed of lamellar-twin domains, shear bands and low-angle lamellar boundaries. Cold-rolled duplex stainless steel, however, exhibited more complicated and mixed microstructure where ferritic lamellar and the heterogeneous nanostructure of austenite were alternatively stacked. The heavily cold-rolled stainless steels followed by ageing exhibited marvelous high tensile strength over 2.6 GPa perpendicular to the rolling direction, although around 2 GPa along the rolling direction. Even while such high strength, moderate plastic elongation over 5% was attained. [ABSTRACT FROM AUTHOR]

Magnesium AZ80 alloy disks were forged under conditions of extremely high pressures beyond their fracture strength in a die which eliminated plastic deformation. With increasing forging stress, mechanical twins were formed more frequently which subdivided the coarse initial grains, and the evolved (0001) basal texture became sharper. The mechanical properties tended to be notably improved with increasing forging stress; their modifications were rapid in the forging stress region just under 400 MPa, but became gradual above 400 MPa. The achieved Vickers hardness, yield stress, and ultimate tensile strength were 950 MPa, 280 MPa, and 436 MPa at best, respectively. The improvement of mechanical properties was reasonably understood from grain refinement due to dense mechanical twinning and texture strengthening, as well as strain hardening. [Display omitted] [ABSTRACT FROM AUTHOR]

We analyzed 3 hematopoietic stem cell transplant ( HSCT) recipients with inherited chromosomally integrated human herpesvirus-6 (inherited CIHHV-6). Cases 1 (inherited CIHHV-6A) and 2 (inherited CIHHV-6B) were inherited CIHHV-6 recipients. Case 3 received bone marrow from a donor with inherited CIHHV-6B. Following HSCT, HHV-6B was isolated from Case 1. HHV-6A and -6B messenger RNAs were detected in Cases 1 and 3. [ABSTRACT FROM AUTHOR]

Two-fluid and the finite Larmor effects on linear and nonlinear growth of the Rayleigh-Taylor instability in a two-dimensional slab are studied numerically with special attention to high-wave-number dynamics and nonlinear structure formation at a low β-value. The two effects stabilize the unstable high wave number modes for a certain range of the β-value. In nonlinear simulations, the absence of the high wave number modes in the linear stage leads to the formation of the density field structure much larger than that in the single-fluid magnetohydrodynamic simulation, together with a sharp density gradient as well as a large velocity difference. The formation of the sharp velocity difference leads to a subsequent Kelvin-Helmholtz-type instability only when both the two-fluid and finite Larmor radius terms are incorporated, whereas it is not observed otherwise. It is shown that the emergence of the secondary instability can modify the outline of the turbulent structures associated with the primary Rayleigh-Taylor instability. [ABSTRACT FROM AUTHOR]

Hall effects on local structures in homogeneous, isotropic, and incompressible magnetohydrodynamic turbulence are studied numerically. The transition of vortices from sheet-like to tubular structures induced by the Hall term is found, while the kinetic energy spectrum does not distinguish the two types of structures. It is shown by the use of the sharp low-pass filter that the transition occurs not only in the scales smaller than the ion skin depth but also in a larger scale. The transition is related with the forward energy transfer in the spectral space. Analyses by the use of the sharp low-pass filter show that the nonlinear energy transfer associated with the Hall term is dominated by the forward transfer and relatively local in the wave number space. A projection of the simulation data to a Smagorinsky-type sub-grid-scale model shows that the high wave number component of the Hall term may possibly be replaced by the model effectively. [ABSTRACT FROM AUTHOR]

As-extruded Mg–Al alloy was multi-directionally forged (MDFed) at room temperature to cumulative strain of ΣΔϵ = 2.0 at maximum by employing a pass strain of Δϵ = 0.1. The coarse initial grains were subdivided gradually to ultra-fine ones by mechanical twinning. The MDFed Mg alloy showed superior mechanical properties of 530 MPa yield and 650 MPa ultimate tensile strengths with ductility of 9%. The relatively large ductility was induced by grain orientation randomization due to multiple twinning and the small pass strains which suppressed the sharp basal-texture evolution. [ABSTRACT FROM AUTHOR]

Abstract: Samples of an AZ61Mg alloy were multi-directionally forged (MDFed) at room temperature employing small pass strains of Δε=0.1 to maximum cumulative strains of ΣΔε =2.5. Ageing at 403K for 1h was carried out before and during MDFing. The coarse initial grains were gradually subdivided into ultrafine ones by mechanical twinning. Twin formation effectively suppressed the development of sharp texture and in this way enabled severe plastic deformation to take place at ambient temperature. Simple ageing of the MDFed sample lowered the strength. However, a combined process of ageing and MDFing increased the hardness and yield stress while it slightly decreased ductility. Good mechanical properties of 500MPa yield stress, 540MPa ultimate tensile strength and 4% plastic strain to fracture were achieved. [Copyright &y& Elsevier]

Powder metallurgy is an effective way to produce the complex shaped soft magnetic materials, and also to decrease the eddy current loss in high frequency by subdividing the eddy current area due to the small grains. Especially, metal injection moulding (MIM) process allows nearly full dense and net shaping of a variety of engineering materials. The application of MIM process to hard and brittle materials such as ferromagnetic materials demonstrates the potential of this novel process. This study considers the processing of three types of soft magnetic materials such as Fe-6·5Si, Fe-9·5Si-5·5Al and Fe-50Ni alloy compacts through the MIM techniques using different types of powders to obtain high performance of soft magnetic properties. [ABSTRACT FROM AUTHOR]

Inter-scale magnetic energy transfer associated with the Hall effects in homogeneous and isotropic magnetohydrodynamics (MHD) turbulence and the applicability of a Smagorinsky-type diffusive sub-grid-scale (SGS) model to Hall MHD turbulence are studied numerically. Low-pass filter analysis on magnetic energy transfer functions shows that their profiles change considerably when the cut-off wave number is comparable to the Taylor-scale wave number. It is shown that the Smagorinsky-type model is applicable to Hall MHD turbulence as a basic SGS model, while the Hall effects tend to overestimate the grid-scale magnetic energy transfer. [ABSTRACT FROM AUTHOR]

Abstract: Mechanisms of grain refinement were investigated in an extruded Mg–6Al–1Zn alloy during hot compression at 623K and a true strain rate of 3×10−3 s−1. With increasing strain, grain fragmentation gradually took place; the dominant grain refinement mechanism, however, depended on the strain. At strains up to ɛ =0.1, mechanical twinning contributed notably to grain refinement and to the formation of high angle boundaries. At medium to high strains, continuous dynamic recrystallization took place. Kinking contributed to grain fragmentation at all strains. The latter two mechanisms also increased the fraction of low to medium angle boundaries. [Copyright &y& Elsevier]

Abstract: In this study, AZ61Mg alloy was multi-directionally forged (MDFed) up to a maximum cumulative strain of ∑Δɛ =4.0 at a true strain rate of 3×10−3 s−1. The MDF temperature was decreased pass-by-pass from 623 to 503K. The average grain size decreased with increasing cumulative strain. After MDF was carried out until ∑Δɛ =4.0, i.e., after five passes, ultrafine grains (UFGs) with an average grain size of 0.8μm were uniformly evolved. Results revealed that UFG evolution was induced by the combined mechanisms of mechanical twinning, kinking, and continuous dynamic recrystallization. The MDFed AZ61Mg alloy exhibited an excellent balance of strength and ductility at room temperature, i.e., an ultimate tensile strength (UTS) of 440MPa and plastic strain to fracture of over 20%. In addition, it exhibited superplasticity at elevated temperatures. Because of its superior deformability, the alloy was further made to undergo a cold rolling procedure to achieve up to 20% reduction. The additional thermo-mechanical processes of cold rolling and/or aging successively raised the UTS of the alloy to 550MPa without much spoiling ductility (plastic strain to fracture of 14%). [Copyright &y& Elsevier]

Abstract: Nano-grain evolution in an austenitic stainless steel (SUS 316) during multidirectional forging (MDF) was investigated at temperatures of 77K and 300K. The flow stress during MDF and the room-temperature hardness increased significantly with increasing cumulative strain. The initial grains were subdivided by mechanical twinning and martensitic transformation. The formation of packets, which are composed of lamellar-structured mechanical twins with a spacing of 10–300nm, enhanced grain fragmentation. The packet size ranged from 40nm to 100nm depending on the MDF temperature and the cumulative strain. Tensile tests at ambient temperatures revealed a maximum proof strength of 2.1GPa. While the proof strength increased with cumulative strain, the plastic strain at fracture was approximately 10% independent of the cumulative strain over ∑Δɛ =2.4. [Copyright &y& Elsevier]

Abstract: Beryllium copper (Cu–Be) alloys exhibit well-balanced properties of strength, elongation and conductivity, and have been used as the conventional material of electrical contacting parts. However, improved materials with higher performances are strongly required for miniaturization of their parts and environmental issues of Be. Recently, an alloy design on the basis of glass-forming rules has enabled the development of Cu–Zr–Ag alloys with tensile strength of 1200 MPa, plastic elongation of 3.1% and electrical conductivity of 30.7% IACS in a thin strip form through the simple production process of casting, cold rolling and annealing. This paper intends to present microstructure and properties of the newly developed alloys and discuss the possibility for applying to electrical contacting materials. [ABSTRACT FROM AUTHOR]

Background: Retrieval studies have demonstrated polyethylene wear and deformation of the anterior aspect of the tibial post of posterior-stabilized total knee replacements. We are not aware of any study that has analyzed the effects of the design of the femoral notch and the anterior aspect of the tibial post of posterior-stabilized total knee replacements on contact area, stress, and location. The purpose of the present study was to determine the levels of contact stress generated in three posterior-stabilized total knee replacement designs when the femoral intercondylar notch impinges on the anterior aspect of the tibial post.Methods: The contact area, mean and peak contact stresses, and contact location at the anterior aspect of the tibial post were determined when a posterior force of 100 N was applied to a NexGen LPS Flex, Genesis II, and Scorpio NRG total knee replacement. Measurements were performed at -15 degrees, -10 degrees, -5 degrees, 0 degrees, and 5 degrees of flexion of the femoral component both in neutral and with 5 degrees of rotation of the tibial component. Each measurement was sequentially performed five times, and the data were compared within and between the designs with use of analysis of variance and a post-hoc Scheffé F test.Results: The NexGen LPS Flex exhibited two contact areas on the medial and lateral corners of the anterior aspect of the post, whereas both the Genesis II and Scorpio NRG exhibited a single horizontal band. The NexGen LPS Flex showed the largest total contact area of the three designs at -15 degrees, -10 degrees, and 5 degrees of flexion. The NexGen LPS showed the lowest mean contact stress at -15 degrees and 5 degrees but showed the highest peak contact stress at -5 degrees and 0 degrees. The Scorpio NRG showed the highest mean contact stress under all conditions and showed the highest peak contact stress at -15 degrees, -10 degrees, and 5 degrees. With 5 degrees of rotation of the tibial component, peak contact stress increased, relative to neutral, 1.2 to twofold (depending on the flexion angle) in the Genesis II design.Conclusions: The mean and peak contact stresses were variable for all three designs and the test conditions, approaching and in some cases exceeding the compressive yield stress for polyethylene. The geometry of the metal femoral notch and polyethylene tibial post in the axial and sagittal planes significantly affected contact area, mean and peak stresses, and contact location at the anterior aspect of the tibial post. [ABSTRACT FROM AUTHOR]

Background: Various treatments for hepatocellular carcinoma (HCC) beneath the diaphragm have been reported. Transpulmonary radiofrequency (TPRF) ablation for HCC beneath the diaphragm has been developed as a safe treatment, but pneumothorax has been reported as the most common complication of TPRF ablation. Purpose: To evaluate the relationship between the incidence of pneumothorax and various variables after TPRF ablation. Material and Methods: Seventy-six TPRF ablation sessions for unresectable HCC were performed in 66 patients (19 women, 47 men; mean age 69.6 years) under computed tomography (CT)-fluoroscopic guidance between November 2005 and April 2009. All patients had HCC beneath the diaphragm, not visible by ultrasonography. In 62 of the 76 sessions, the number of transpulmonary approaches was one as adequate, while multiple transpulmonary approaches were performed in 14 of the 76 sessions. The rate of pneumothorax and risk factors for pneumothorax were investigated. Results: Among the 76 sessions, pneumothorax was detected in 51 sessions (67.1%). Among the 14 sessions with multiple transpulmonary passages, pneumothorax was detected in 13 (92.9%), while in the 62 sessions with a single transpulmonary passage, pneumothorax occurred in 38 sessions (61.3%). Hence, the number of transpulmonary approaches was a significant factor (P=0.0232). Among 13 variables investigated for the 62 sessions with a single transpulmonary approach, the only significant factor correlated with the occurrence of pneumothorax was the length of the needle trajectory through the aerated lung (P=0.0014). The incidence of chest tube placement was 7.9%. Conclusion: Pneumothorax occurred frequently after TPRF ablation for HCC. The main risk factors for pneumothorax after TPRF ablation for HCC were increased length of needle trajectory through the aerated lung and multiple transpulmonary approaches in one session. Even if pneumothorax occurred, pneumothorax disappeared spontaneously or with simple treatment such as manual aspiration in most cases. [ABSTRACT FROM AUTHOR]

A fine-grained Cu-30%Zn alloy sheet was rolled at 77 K to induce ultrafine mechanical twins. Subsequent annealing of the rolled alloy at temperatures up to 543 K led to the uniform appearance of recrystallized ultrafine grains (UFGs), which contained numerous annealing twins. Average grain sizes of 150 ∼ 300 nm were produced in this way. The formation of such UFGs during annealing is attributed to the high nucleus density associated with the fine initial grain size as well as to the high densities of mechanical twins and dislocations produced by cryorolling. The high driving force for recrystallization enabled the use of relatively low annealing temperatures, which limited the subsequent grain growth. [ABSTRACT FROM AUTHOR]

Abstract: Cyclic creep and fracture behavior at 673K of orientation-controlled Cu–SiO2 bicrystals with [001] twist 20° grain boundaries was investigated. The cyclic creep and life depended on both the stress amplitude and the frequency of the cyclic load. Most bicrystals fractured intergranularly. The number of cycles to failure shortened drastically with decreasing the frequency and with increasing the stress amplitude, while the time to failure remained nearly the same irrespective of the frequency. Since the cyclic creep life was controlled by the occurrence of grain-boundary fracture, the above observations can be understood reasonably by considering stress concentration and void formation at grain-boundary SiO2 particles. When grain-boundary sliding takes place, the particles impede the sliding and the stress concentration sites are created. This causes the intergranular fracture and controls the cyclic creep life. [Copyright &y& Elsevier]

Abstract: Electron spin resonance (ESR) dating has been applied previously to quartz derived from tephra deposits using the additive dose method. In this study we compare results obtained using both additive dose and regeneration dose methods on a Japanese tephra sample. A further intercomparison is carried out using two different signals corresponding to Al and Ti–Li centres, and two different grain sizes (0.25–0.5mm and 0.5–1mm). Possible sensitivity changes due to heating required for zeroing the signals was checked by the regenerative – additive dose technique. The estimates of equivalent dose (D E) obtained using the regeneration method were generally consistent with those obtained using additive dose; however, as expected the uncertainties were much smaller for the regeneration D E estimates. A significant difference was observed between the equivalent dose (D E) derived using the Al or Ti–Li centres, and using different grain sizes. [Copyright &y& Elsevier]

Abstract: The evolution mechanisms of new high-angle boundaries as well as ultrafine grains at large strains were studied by means of multidirectional forging (MDF) of pure copper at low temperature and aluminum alloy at high temperature, where dynamic recovery operates as a main restoration process. The structural changes can be characterized by the evolution of deformation bands such as microshear or kink bands at moderate strains. Multidirectional forging accelerates the evolution of many mutually crossing microshear or kink bands developed in various directions. The misorientations between (sub)grains increased gradually with increasing cumulative strain, finally leading to the development of a new fine-grained structure. The dynamic grain formation can be resulted from in situ or continuous dynamic recrystallization which is discussed in detail. [Copyright &y& Elsevier]

Abstract: Effect of strain rate and its discontinuous changes on the deformation and microstructural behavior of a coarse-grained 7475 Al alloy were studied in multidirectional forging at 763K. Deformation at a higher strain rate of 3×10−2 s−1, controlled by homogeneous dislocation motion, leads to partial grain refinement taking place only near the original grain boundaries. Deformation at a lower rate of 3×10−4 s−1, controlled mainly by grain boundary sliding, in contrast, results in full development of strain-induced grains through grain fragmentation due to microshear band formation. Under conditions of discontinuous changes in strain rate, the flow stresses and grain size developed by subsequent severe deformation do not approach those appearing during continuous change at a constant strain rate. The nature of such strain-induced events is irreversible and athermal. The mechanisms of continuous dynamic recrystallization operating during severe deformation are discussed in detail. [Copyright &y& Elsevier]

OBJECTIVE: Finite element analysis of clinical computed tomography (CT) scans provides a noninvasive means of assessing vertebral strength that is superior to dual x-ray absorptiometry (DXA)-measured areal bone mineral density. The present study was undertaken to compare strength changes, measured using this newer method, in rheumatoid arthritis (RA) patients who were treated with alendronate (ALN) versus those who were not. METHODS: Thirty female RA patients without radiologic signs of L3 compression fractures or a history of osteoporosis medication were enrolled in a prospective randomized clinical trial. Patients were randomly assigned to the ALN group (5 mg orally, once daily) or the control group not receiving antiresorptive treatment. All patients were evaluated by DXA and quantitative CT at baseline and reevaluated after a mean of 12.2 months. Nonlinear finite element analysis was performed on the CT scans (n = 29 available for analysis) to compute an estimate of vertebral compressive strength and to assess strength changes associated with changes in the trabecular compartment and the outer 2 mm of bone (peripheral compartment). RESULTS: On average, vertebral strength was significantly decreased from baseline in the control group (n = 15) (median change -10.6%; P = 0.008) but was maintained in the ALN group (n = 14) (median change +0.4%; P = 0.55), with a significant difference between the 2 groups (P < 0.01). Strength decreased more rapidly within the trabecular bone, and ALN treatment was much more effective in the peripheral than the trabecular compartment. CONCLUSION: Our results indicate that patients with RA can lose a substantial amount of vertebral strength over a relatively short period of time, and this loss can be prevented by ALN, primarily via its positive effect on the outer 2 mm of vertebral bone. [ABSTRACT FROM AUTHOR]

Abstract: The effect of particle/matrix interfacial character on the high-temperature deformation and recrystallization behavior of Cu was systematically investigated at various temperatures from 723 to 973K and at true strain rates between 4.1×10−4 and 3.2×10−2 s−1. Cu with dispersed coherent γ-Fe precipitates (Cu–γ-Fe alloy) displayed lower yield stresses and higher flow stresses than Cu containing incoherent α-Fe precipitates (Cu–α-Fe alloy) under all testing conditions. Dynamic recrystallization (DRX) took place more easily in the Cu–α-Fe alloy than in the Cu–γ-Fe alloy. Although DRX was strongly impeded by the presence of the coherent precipitates at low to medium strains, the recrystallized regions gradually spread, accompanied by transformation of the coherent precipitates into incoherent ones. Such a large difference in the deformation and DRX behaviors depending on the particle/matrix interfacial character is attributed to the stronger interaction between dislocations and the coherent particles. [Copyright &y& Elsevier]

A bulky Cu-Zn alloy was multi-directionally forged (MDFed) at 77 K and 300 K up to a cumulative strain of 6.0 at maximum. With increasing strain, the evolved substructure changed gradually to uniform ultra fine grains. The tendency of the microstructural evolution and its mechanism depended strongly on the MDF temperature. Mechanical twins accelerated the finer grain fragmentation by subdivision of the grains and by intersection of the twins themselves due to MDF. Twinning appeared more frequently and uniformly at 77 K than at 300 K. The average grain size obtained at a cumulative strain of 6.0 was about 17 nm at 77 K and 26 nm at 300 K. The evolution of the microstructure accompanied by mechanical twinning is precisely investigated. [ABSTRACT FROM AUTHOR]

Abstract: A carbon steel containing dispersed fine voids, with diameters in the range of 3–5μm, was deformed in compression at temperatures between 1063K and 1153K and at true strain rates from 4.2×10−5 s−1 to 4.2×10−3 s−1. The deformation behavior did not differ much from that of a carbon steel without voids. The maximum stress and the corresponding maximum strain increased in the presence of a dispersion of voids, and, as a consequence the occurrence of dynamic recrystallization (DRX) was also slightly delayed. Furthermore, the yield stress and the steady-state stress increased by about 10%. The shape and distribution of voids changed depending upon strain, strain rate and temperature. With decreasing strain rate and increasing temperature, the aspect ratio of the voids decreased. These observed effect of voids on high temperature deformation behavior and the void shape change during deformation are discussed in relation with such mechanisms as DRX, grain boundary migration, grain boundary sliding and relaxation. [Copyright &y& Elsevier]

Orientation-controlled copper bicrystals containing [001] symmetrical tilt boundaries aligned parallel to the loading axis were deformed in tension at 923 K and a strain rate of 4.2 × 10-4 s-1. The nucleation of dynamic recrystallization (DRX) was investigated along the grain boundary. For this purpose, both optical and orientation imaging microscopy methods were used. After grain-boundary migration (GBM) and bulging, nuclei appeared behind the most deeply indented grain boundary regions. The critical strain for nucleation was about one-quarter to one-half of the peak strain and depended on the misorientation angle. All the nuclei were twin-related (Σ3) to the matrices. Furthermore, all the primary twin traces were parallel to those of the inactive slip planes of the parent single crystals. Crystallographic analysis revealed the important role of the direction of GBM on twinning-plane variant selection. The characteristics of grain boundary nucleation depended sensitively on grain boundary character and on grain boundary mobility. The observed DRX nucleation mechanism is discussed in relation to the occurrence of GBM and twinning. [ABSTRACT FROM AUTHOR]

BACKGROUND: In the clinical evaluation of the anterior cruciate ligament-deficient knee, anterolateral rotatory instability is assessed by manual tests such as the pivot-shift test, which is subjective and not quantitative. HYPOTHESIS: The anterolateral rotatory instability in an anterior cruciate ligament-deficient knee can be quantified by our newly developed method using open magnetic resonance imaging. STUDY DESIGN: Controlled laboratory study. METHODS: Eighteen subjects with anterior cruciate ligament-deficient knees and 18 with normal knees were recruited. We administered the Slocum anterolateral rotatory instability test in the open magnetic resonance imaging scanner and scanned the sagittal view of the knee. The anterior displacements of the tibia at the medial and lateral compartments were measured. Furthermore, we examined 14 anterior cruciate ligament-deficient knees twice to assess intraobserver and interobserver reproducibility and evaluated the difference and interclass correlation coefficient of 2 measures. RESULTS: In the anterior cruciate ligament-deficient knee, displacement was 14.4 +/- 5.5 mm at the lateral compartment and 1.6 +/- 2.3 mm at the medial compartment; in the normal knee, displacement was 0.7 +/- 1.9 mm and -1.1 +/- 1.2 mm, respectively. The difference and interclass correlation coefficient between 2 repeated measures at the lateral compartment were 1.0 +/- 0.7 mm and .98 for intraobserver reproducibility and 1.1 +/- 0.7 mm and .91 for interobserver reproducibility. CONCLUSION: This method is useful to assess the anterolateral rotatory instability of the anterior cruciate ligament-deficient knee. CLINICAL RELEVANCE: This method can be used in the clinical assessment of anterior cruciate ligament stability, such as comparing studies of graft positions or 2-bundle anatomic reconstruction and the conventional 1-bundle technique. [ABSTRACT FROM AUTHOR]

The purpose of the present study was to develop a new assessment scale to evaluate the risk of chewing and swallowing disorders among frail community-dwelling elderly individuals. Subjects were 85 frail elderly individuals (29 men and 56 women) living in southern Japan. First, we pooled 18 subjectively evaluated variables identified by previous studies as being related to chewing and swallowing disorders. Secondly, using factor analysis, we extracted 12 variables as the ‘dysphagia risk assessment for the community-dwelling elderly’ (DRACE) and examined its reliability using Cronbach's alpha coefficient. Thirdly, we examined the validity of the DRACE by comparing it with an existing method for evaluating dysphagia. Cronbach's alpha coefficient of the DRACE was 0·88, indicating satisfactory reliability. Dysphagia risk assessment for the community-dwelling elderly scores were significantly related to the results of the 3-oz water test ( P < 0·01). Furthermore, DRACE scores were closely associated with activities of daily living as evaluated by the Barthel index, a tendency that was consistent with previous studies. These findings suggest that the DRACE is a useful tool with sufficient reliability and validity to detect latent risk of chewing and swallowing disorders among frail community-dwelling elderly individuals. [ABSTRACT FROM AUTHOR]

The preferential nucleation of grains at triple junctions (TJs) during high temperature deformation was investigated systematically using a copper tricrystal. Their relationships to the parent grain were also determined. All the new grains were twin-related to the matrix and were formed by means of grain boundary migration (GBM). Selection of the twinning plane depended sensitively on the direction of GBM and on the geometry of the grain boundaries composing the TJ. It did not seem to be affected by slip plane activity or by the Schmid factor of the parent grain. [Copyright &y& Elsevier]

The high temperature deformation behavior of Mg single crystals was precisely investigated using orientation imaging microscopy. For this purpose, Mg single crystals of various orientations were tensile tested in vacuum at temperatures between 473 and 673&ThickSpace;K. A strain rate of 4.2&ThickSpace;×&ThickSpace;10 -4 &ThickSpace;s -1 was employed. The elongations to fracture depended strongly on crystal orientation, the lowest fracture strains being associated with multiple slip. Single crystals in which single slip was activated exhibited extended ductilities corresponding to more than 1.5 in true strain. The strong orientation dependence of the ductility can also be correlated with the ease of occurrence of dynamic recrystallization (DRX), which took place in the multiple-slip specimens. The role of twinning in the initiation of DRX is also discussed. [ABSTRACT FROM AUTHOR]

The preferential nucleation of dynamic recrystallization (DRX) was investigated in copper polycrystals. DRX nucleation began to appear preferentially at triple junctions (TJs) at around 0.01 strain irrespective of the testing conditions, i.e. at only about 1/10 to 1/20 of the peak strain. The likelihood of DRX nucleation at TJs increased monotonically with strain. Furthermore, this probability also depended strongly on the strain rate, temperature and initial grain size. More than 80% of the grains nucleated at TJs were twins. The observed likelihood of DRX nucleation at TJs was closely related to the amount of grain-boundary sliding, fold formation at the TJs, the misorientation angle of the grain boundaries composing the TJ, and the angle between the tensile axis and the sliding grain boundary. The mechanisms determining the strain-rate dependence of DRX nucleation and twin formation are discussed in detail in relation to the above factors. [ABSTRACT FROM AUTHOR]

Abstract: Chondrule formation due to the shock wave heating of dust particles with a wide variety of shock properties are examined. We numerically simulate the steady postshock region in a framework of one-dimensional hydrodynamics, taking into account many of the physical and chemical processes that determine the properties of the region, especially nonequilibrium chemical reactions of gas species. We mainly focus on the dust particle shrinkage due to the evaporation in the postshock hot gas and the precursor size conditions for chondrule formation. We find that the small precursors whose radii are smaller than a critical value, , cannot form chondrules because they evaporate away completely in the postshock region. The minimum value of is about 10 μm, though it depends on the shock speed and the preshock gas density. Furthermore, we demonstrate the chondrule size distributions which are formed through the shock-wave heating. These results indicate that the shock-wave heating model can be regarded as a strong candidate for the mechanism of chondrule formation. [Copyright &y& Elsevier]

The authors investigated the effects of fluvoxamine on neurochemical changes in the hippocampus elicited by isolation housing and novelty stress. Male F344 rats (11 w) were housed one per cage for four weeks. On each day of the last week (7 days) they were s.c. injected with fluvoxamine (20 mg/kg), and then subjected to novelty stress. Isolation housing significantly increased dihydroxyphenylacetic acid (DOPAC) and 5-hydroxyindoleacetic acid (5-HIAA) levels, whereas fluvoxamine significantly decreased them. Isolation housing significantly increased the DOPAC/DA ratio. Fluvoxamine significantly decreased the DA level, and partially restored the DOPAC and 5-HIAA levels increased by isolation housing. [ABSTRACT FROM AUTHOR]

Rationale: Tetrahydrobiopterin (BH4) is a coenzyme of tyrosine hydroxylase (TH) and tryptophan hydroxylase (TPH), rate-limiting enzymes of monoamine biosynthesis. According to the monoamine hypothesis of depression, antidepressants will restore the function of the brain monoaminergic system, and BH4 concentration. Objective: To investigate the effects of fluvoxamine on BH4 levels and dopamine (DA) and serotonin (5-HT) turnover in the mesoprefrontal system, incorporating two risk factors of depression, social isolation and acute environmental change. Methods: Male ddY mice (6W) were divided into two housing groups, i.e. group-housing (eight animals per cage; 35 days), and isolation-housing (one per cage; 35 days), SC injected with fluvoxamine (20 or 40 mg/kg; days 29-35), and exposed to 20-min novelty stress (day 35). The levels of BH4, DA, homovanilic acid (HVA), 5-HT, and 5-hydroxyindoleacetic acid (5-HIAA) were measured in the prefrontal cortex and midbrain. Results: Under the group-housing condition, novelty stress significantly increased BH4 levels in both regions, and the HVA/DA ratio in the midbrain, whereas it did not change any parameters in either region under the isolation-housing condition. In the prefrontal cortex, fluvoxamine significantly decreased the 5-HIAA/5-HT ratio under the group-housing condition, and BH4 levels and the HVA/ DA ratio under the isolation-housing condition. In the midbrain, fluvoxamine significantly decreased all parameters, except for an increasing in the 5-HIAA/5-HT ratio under the isolation-housing condition. Conclusion: Isolation-housing suppressed the increase of BH4 levels and DA turnover elicited by novelty stress. Fluvoxamine suppressed BH4 levels, and DA and 5-HT turnover. Fluvoxamine may have altered DA turnover by suppressing BH4 levels. [ABSTRACT FROM AUTHOR]

The nucleation mechanisms of dynamic recrystallization (DRX) were investigated in copper bicrystals deformed in tension at 923 K at a strain rate of 4.2×10−4 s−1. The boundary plane was either parallel or inclined to the tensile axis. The grain boundaries were observed to migrate locally and to form bulges. Nuclei appeared preferentially at the migrating grain boundaries at a strain as low as ε=0.15, i.e. only about half of the peak strain. All nucleated grains were identified as twins (Σ3) to one of the two adjacent crystals. The twinning planes coincided preferentially with a secondary slip plane of the adjoining crystals. The DRX nucleation mechanisms at grain boundaries are discussed with respect to grain boundary migration and recrystallization twinning. [Copyright &y& Elsevier]

We measured changes in plasma ghrelin and GH concentrations in mature Holstein cows and 3-mo-old female Holstein calves fed at scheduled times. Our objective was to determine the characteristics of ghrelin secretion in dairy cattle and its influence on GH. Animals were fed at 0800 and 1600 for 2 wk before and during experiments. Plasma was sampled for 24 h at 2-h intervals in Exp. 1. In mature cows, plasma ghrelin concentrations decreased (P < 0.01)just after 0800 but not at the 1600 feeding. Ghrelin concentrations were lower (P < 0.01) in calves than in mature cows and they did not decrease after feeding in calves. The temporal relationship between ghrelin and GH remained unclear. In Exp. 2, plasma was sampled 2 h before and aider both morning and evening feedings at 20-min intervals. Plasma ghrelin concentrations decreased (P < 0.05) 40 min mature 0800 feeding and 60 rain after 1600 feeding in mature cows. These results indicate that in mature cows, plasma ghrelin concentration decreased after feeding, but this decrease was not evident in 3-mo-old calves. Further studies are required to define the relationship between plasma ghrelin and GH concentrations. [ABSTRACT FROM AUTHOR]

In the present study, we investigated the effects of fluvoxamine, a selective serotonin reuptake inhibitor, on brain tetrahydrobiopterin (BH4) levels. We directly measured levels of BH4 by Tani and Ohno’s direct method as well as the serotonin (5-HT) turnover ratio, i.e. 5-hydroxyindoleacetic acid (5-HIAA)/5-HT, after sub-acute s.c. injection of fluvoxamine in the hippocampus of mice. Our animal model incorporated two risk factors of depression, social isolation and acute environmental change. Male ddY mice (6W) were housed in isolation (1 per cage; 35 days), injected with fluvoxamine (20 or 40 mg/kg; days 29–35), and exposed to novelty stress (20 min; day 35). In the stress session, behavioral parameters, i.e. total distance and rearing behavior, were measured. Isolation housing increased both behaviors. Fluvoxamine attenuated rearing behavior, but did not influence total distance. Isolation housing increased BH4 levels. Novelty stress increased BH4 levels in group housing, although it did not change them in isolation housing. Fluvoxamine suppressed BH4 levels. In isolation housing, fluvoxamine increased 5-HT turnover ratios, while it decreased them in group housing. In conclusion, fluvoxamine, housing condition, and novelty stress regulated BH4 levels. Fluvoxamine may have changed behavior and 5-HT turnover by suppressing BH4 levels as well as by inhibiting 5-HT reuptake. [Copyright &y& Elsevier]