Spin caloritronics in metallic superlattices.

Spin caloritronics, a research field studying on the interconversion between a charge current (Jc) and a heat current (Jq) mediated by a spin current (Js) and/or magnetization (M), has attracted much attention not only for academic interest but also for practical applications. Newly discovered spin-caloritronic phenomena such as the spin Seebeck effect (SSE) have stimulated the renewed interest in the thermoelectric phenomena of a magnet, which have been known for a long time, e.g. the anomalous Nernst effect (ANE). These spin-caloritronic phenomena involving the SSE and the ANE have provided with a new direction for thermoelectric conversion exploitingJsand/orM. Importantly, the symmetry of ANE allows the thermoelectric conversion in the transverse configuration betweenJqandJc. Although the transverse configuration is totally different from the conventional longitudinal configuration based on the Seebeck effect and has many advantages, we are still facing several issues that need to be solved before developing practical applications. The primal issue is the improvement of conversion efficiency. In the case of ANE-based applications, a material with a large anomalous Nernst coefficient (SANE) is the key for solving the issue. This review article introduces the increase ofSANEcan be achieved by forming superlattice structures, which has been demonstrated for several kinds of materials combinations. The overall picture of studies on spin caloritronics is first surveyed. Then, we mention the pioneering work on the transverse thermoelectric conversion in superlattice structures, which was performed using Fe-based metallic superlattices, and show the recent studies for the Ni-based metallic superlattices and the ordered alloy-based metallic superlattices.

Efficacy of repeated administration of intravenous acetaminophen for pain management after total knee arthroplasty.

Intravenous acetaminophen is an integral component of multimodal postoperative pain management. This prospective study aims to assess the efficacy of the repeated administration of intravenous acetaminophen and the impact on postoperative patient satisfaction with postoperative pain management after total knee arthroplasty (TKA). We enrolled 98 patients scheduled for unilateral TKA. Patients were randomly assigned to receive either 1000 mg of intravenous acetaminophen at 6-hour intervals (AAP group) or not to receive intravenous acetaminophen (control group). All patients underwent single-shot femoral nerve block after general anesthesia, as well as intraoperative periarticular infiltration of analgesia prior to implantation. The primary outcome was the postoperative numerical rating scale (NRS) pain score at rest. The NRS score was measured just before the administration of study drugs, immediately after arrival in the ward (time 0), and at 6, 12, 18, 24, and 48 h (time 1 to time 5, respectively) postoperatively. We also evaluated the mean doses of rescue opioid use for 24 h postoperatively. At time 5, the AAP group had significantly improved mean NRS score than controls (3.0 vs. 4.0; P < 0.01). Rescue opioid use was significantly lower in the AAP group for 24 hours compared to controls (0.3 µg vs. 0.9 µg; P < 0.01). Repeated intravenous acetaminophen administration after TKA may provide better analgesia and reduce opioid use.

Influence of the strain effect on magnetocrystalline anisotropy in Co2Fe0.4Mn0.6Si Heusler alloys.

The perpendicular magnetocrystalline anisotropy, magnetoelastic properties as well as the Gilbert damping factor in Co2Fe0.4Mn0.6Si thin films were found to depend on a magnetic layer thickness, and they can be also tuned by the application of additional Ag buffer layer. The tetragonal distortion of a magnetic layer was found to increase with decreasing thickness, and after the application of an additional Ag buffer layer, the character of this distortion was changed from tensile to compressive in the plane of a film. A correlation between the tetragonal distortion and perpendicular magnetocrystalline anisotropy was found. However, the magnitude of the observed tetragonal distortion for most samples seems to be too small to explain alone the experimentally found large magnitude of the perpendicular magnetocrystalline anisotropy. For these samples, other mechanisms including both surface and volume effects must be taken into account.

Development of multichord ion Doppler spectroscopy system for toroidal flow measurement of field-reversed configuration.

A double-chord ion Doppler spectroscopy (IDS) system was developed to measure the ion temperature and flow velocity of field-reversed configuration (FRC) plasmas in the FRC amplification via a translation-collisional merging (FAT-CM) device. Adopting a Czerny-Turner mount monochromator and 16-channel photomultiplier tube array, the developed IDS system achieves high wavelength resolution and fast time response. In addition, two vertically aligned optical paths share the optical system up to the monochromator and then branch just before the detector, successfully reducing crosstalk to <1%. The Doppler broadening was measured at two measurement points in the FAT-CM device, simultaneously, and ion temperatures of ∼50 eV were measured. Toroidal spin-up from 7 to 15 km/s and a steady flow velocity of ∼10 km/s were estimated from the Doppler shift obtained by the developed system. The observation of the toroidal flow velocity and the spatial profile of the ion temperature of the FRC plasma in the FAT-CM device were realized. These spectroscopic diagnostic's double chord capabilities will aid in understanding and improving the FRC plasmas.

Spectroscopic observation of super-Alfvénic field-reversed configuration merging process by mixing of tracer ions.

Visualization of the collisional merging formation process of field-reversed configuration (FRC) has been attempted. In the collisional merging formation process, two initial FRC-like plasmoids are accelerated toward each other by a magnetic pressure gradient. The relative speed of the collision reaches several times the typical ion sonic speed and Alfvénic speed. The magnetic structure of the initial-FRCs is disrupted in the collision process, but the FRC-like magnetic structure is reformed in ∼30 µs after the collision. Magnetic reconnection should occur in this process; however, general theoretical models in magnetohydrodynamics approximation cannot be applied to this process because of the high-beta nature of FRC and super-Alfvénic/sonic relative speed. In this work, the spectroscopic observation of the collisional merging FRC formation was conducted to evaluate the timescale and geometry of merging. A slight amount of tracer element (e.g., helium) was mixed into one of two initial-FRCs. Mixing of the tracer did not cause serious adverse effects on the performance of the initial-FRC in the collision and merging processes. The collision and merging processes were visualized successfully and observed using a fast-framing camera with a bandpass filter. The timescale of merging and the outflow speed in the collisional merging process of FRCs were optically evaluated for the first time.

Development of visible light tomographic imaging system for field-reversed configuration collisional merging experiment.

A visible light tomographic imaging system has been developed for the collisional merging experiment of field-reversed configurations (FRCs) on the FRC Amplification via Translation-Collisional Merging device at Nihon University. Two FRCs formed by field-reversed theta-pinch translate at super-Alfvénic velocity and collide with each other. The translation and collision processes are completed in 20-30 µs, and a single FRC is reformed in ∼70 µs. To study these translation and collisional merging processes, the tomographic system, including fast response tomographic cameras and a reconstruction method assuming a Rigid-Rotor (RR) model, is developed. The developed tomographic cameras simply consist of 16 channels of multi-anode photomultipliers, a band-pass filter, a slit, and a cylindrical lens, which expands the viewing angle. Because the viewing angle is limited by the size of the viewports of the metal chamber, the iterative method assuming the RR model has been applied to reconstruct tomographic images from a small number of projections. The developed tomographic imaging system can estimate the behavior of FRCs. Four cameras are installed in the two cross sections near the collision point. The radial shift of each translated FRC can be calculated by this system. Details of the developed tomographic camera system and RR reconstruction method are reported.

Magnetoelastic interactions and magnetic damping in Co2Fe0.4Mn0.6Si and Co2FeGa0.5Ge0.5 Heusler alloys thin films for spintronic applications.

Co2Fe0.4Mn0.6Si (CFMS) and Co2FeGa0.5Ge0.5 (CFGG) Heusler alloys are among the most promising thin film materials for spintronic devices due to a high spin polarization, low magnetic damping and giant/tunneling magnetoresistance ratios. Despite numerous investigations of Heusler alloys magnetic properties performed up to now, magnetoelastic effects in these materials remain not fully understood; due to quite rare studies of correlations between magnetoelastic and other magnetic properties, such as magnetic dissipation or magnetic anisotropy. In this research we have investigated epitaxial CFMS and CFGG Heusler alloys thin films of thickness in the range of 15-50 nm. We have determined the magnetoelastic tensor components and magnetic damping parameters as a function of the magnetic layer thickness. Magnetic damping measurements revealed the existence of non-Gilbert dissipation related contributions, including two-magnon scattering and spin pumping phenomena. Magnetoelastic constant B11 values and the effective magnetic damping parameter αeff values were found to be in the range of - 6 to 30 × 106 erg/cm3 and between 1 and 12 × 10-3, respectively. The values of saturation magnetostriction λS for CFMS Heusler alloy thin films were also obtained using the strain modulated ferromagnetic resonance technique. The correlation between αeff and B11, depending on magnetic layer thickness was determined based on the performed investigations of the above mentioned magnetic properties.

Factors limiting quantitative phase retrieval in atomic-resolution differential phase contrast scanning transmission electron microscopy using a segmented detector.

Quantitative differential phase contrast imaging of materials in atomic-resolution scanning transmission electron microscopy using segmented detectors is limited by various factors, including coherent and incoherent aberrations, detector positioning and uniformity, and scan-distortion. By comparing experimental case studies of monolayer and few-layer graphene with image simulations, we explore which parameters require the most precise characterisation for reliable and quantitative interpretation of the reconstructed phases. Coherent and incoherent lens aberrations are found to have the most significant impact. For images over a large field of view, the impact of noise and non-periodic boundary conditions are appreciable, but in this case study have less of an impact than artefacts introduced by beam deflections coupling to beam scanning (imperfect tilt-shift purity).

Histamine-2 receptor antagonists (H2RA) may negatively impact ADL assessment in patients on a convalescent rehabilitation ward.

Background/aim: In the convalescent rehabilitation ward, many elderly patients undergo rehabilitation. Histamine-2 receptor antagonists (H2RA), which is a one of the acid secretion inhibitors, is frequently prescribed for the patients as a peptic ulcer prevention measure. At present, H2RA are reported as being associated with factors that reduce cognitive function. However, little is known about the relationship H2RA and rehabilitation outcome. Therefore, this study examined the relationship between H2RA use and Functional Independence Measure (FIM) gain, which determines rehabilitation outcomes for patients admitted to the convalescent rehabilitation ward. Patients and methods: We retrospectively investigated FIM gain on discharge by both the administration group (H2RA (+)) (n = 118) and non-administration group (H2RA (-)) (n = 118). Results: The FIM gain scores of Motor FIM total, Cognition FIM total, and Total FIM were significantly lower in H2RA (+) than in H2RA (-) (Motor FIM total: 8.0 [4.0-16.0] [Inter-Quartile Range] vs. 12.0 [5.0-19.2], p =0.0217, Cognition FIM total: 3.0 [1.0-6.0] vs. 5.0 [2.0-7.0], p =0.0120, Total FIM: 11.5 [4.8-20.2] vs. 17.0 [8.0-27.0], p =0.0089). Conclusion: The administration of H2RA to elderly patients undergoing rehabilitation may prevent cognitive function maintenance or recovery by rehabilitation.

Anticholinergic Load and Nutritional Status in Older Individuals.

OBJECTIVES: The association between anticholinergic load-based Anticholinergic Risk Scale scores and nutritional status is unclear in Japanese patients. The aim of this study was to establish whether anticholinergic load affects the nutritional status of geriatric patients in convalescent stages. DESIGN: Retrospective longitudinal cohort study. SETTING: Convalescent rehabilitation wards. PARTICIPANTS: Of the 1490 patients aged ≥65 years who were discharged from convalescent rehabilitation wards between July 2010 and October 2018, 908 patients met the eligibility criteria. They were categorized according to the presence or absence of increased anticholinergic load from admission to discharge. MEASUREMENTS: Demographic data, laboratory data, the Functional Independence Measure were analyzed between the groups. The primary outcome was Geriatric Nutritional Risk Index (GNRI) at discharge. Multiple linear regression analysis was performed to analyze the relationship between anticholinergic load and GNRI at discharge. RESULTS: Multiple linear regression analysis after adjusting for confounding factors revealed that anticholinergic load was independently and negatively correlated with GNRI at discharge. Particularly, the use of chlorpromazine, hydroxyzine, haloperidol, metoclopramide, risperidone, etc. increased significantly from admission to discharge. CONCLUSION: Increased anticholinergic load during hospitalization may be a predictor of nutritional status in geriatric patients.

Polarization control with an X-ray phase retarder for high-time-resolution pump-probe experiments at SACLA.

Control of the polarization of an X-ray free-electron laser (XFEL) has been performed using an X-ray phase retarder (XPR) in combination with an arrival timing diagnostic on BL3 of the SPring-8 Angstrom Compact free-electron LAser (SACLA). To combine with the timing diagnostic, a pink beam was incident on the XPR crystal and then monochromated in the vicinity of samples. A high degree of circular polarization of ∼97% was obtained experimentally at 11.567 keV, which agreed with calculations based on the dynamical theory of X-ray diffraction. This system enables pump-probe experiments to be operated using circular polarization with a time resolution of 40 fs to investigate ultrafast magnetic phenomena.

Atomic resolution electron microscopy in a magnetic field free environment.

Atomic-resolution electron microscopes utilize high-power magnetic lenses to produce magnified images of the atomic details of matter. Doing so involves placing samples inside the magnetic objective lens, where magnetic fields of up to a few tesla are always exerted. This can largely alter, or even destroy, the magnetic and physical structures of interest. Here, we describe a newly developed magnetic objective lens system that realizes a magnetic field free environment at the sample position. Combined with a higher-order aberration corrector, we achieve direct, atom-resolved imaging with sub-Å spatial resolution with a residual magnetic field of less than 0.2 mT at the sample position. This capability enables direct atom-resolved imaging of magnetic materials such as silicon steels. Removing the need to subject samples to high magnetic field environments enables a new stage in atomic resolution electron microscopy that realizes direct, atomic-level observation of samples without unwanted high magnetic field effects.

Prepatterning of Papilio xuthus caterpillar camouflage is controlled by three homeobox genes: clawless, abdominal-A, and Abdominal-B.

Color patterns often function as camouflage to protect insects from predators. In most swallowtail butterflies, younger larvae mimic bird droppings but change their pattern to mimic their host plants during their final molt. This pattern change is determined during the early fourth instar by juvenile hormone (JH-sensitive period), but it remains unclear how the prepatterning process is controlled. Using Papilio xuthus larvae, we performed transcriptome comparisons to identify three camouflage pattern-associated homeobox genes [clawless, abdominal-A, and Abdominal-B (Abd-B)] that are up-regulated during the JH-sensitive period in a region-specific manner. Electroporation-mediated knockdown of each gene at the third instar caused loss or change of original fifth instar patterns, but not the fourth instar mimetic pattern, and knockdown of Abd-B after the JH-sensitive period had no effect on fifth instar patterns. These results indicate the role of these genes during the JH-sensitive period and in the control of the prepatterning gene network.

Fe-Sn nanocrystalline films for flexible magnetic sensors with high thermal stability.

The interplay of magnetism and spin-orbit coupling on an Fe kagome lattice in Fe3Sn2 crystal produces a unique band structure leading to an order of magnitude larger anomalous Hall effect than in conventional ferromagnetic metals. In this work, we demonstrate that Fe-Sn nanocrystalline films also exhibit a large anomalous Hall effect, being applicable to magnetic sensors that satisfy both high sensitivity and thermal stability. In the films prepared by a co-sputtering technique at room temperature, the partial development of crystalline lattice order appears as nanocrystals of the Fe-Sn kagome layer. The tangent of Hall angle, the ratio of Hall resistivity to longitudinal resistivity, is maximized in the optimal alloy composition of close to Fe3Sn2, implying the possible contribution of the kagome origin even though the films are composed of nanocrystal and amorphous-like domains. These ferromagnetic Fe-Sn films possess great advantages as a Hall sensor over semiconductors in thermal stability owing to the weak temperature dependence of the anomalous Hall responses. Moreover, the room-temperature fabrication enables us to develop a mechanically flexible Hall sensor on an organic substrate. These demonstrations manifest the potential of ferromagnetic kagome metals as untapped reservoir for designing new functional devices.

Anticholinergic load negatively correlates with recovery of cognitive activities of daily living for geriatric patients after stroke in the convalescent stage.

WHAT IS KNOWN AND OBJECTIVE: Anticholinergic drugs are associated with risks of falls, confusion and cognitive dysfunction. However, the effect of anticholinergic drug use on rehabilitation outcomes after a stroke is poorly documented. We therefore aimed to establish whether the anticholinergic load was associated with functional recovery among geriatric patients convalescing after stroke. METHOD: Consecutive geriatric stroke patients admitted and discharged from a convalescence rehabilitation ward between 2010 and 2016 were included in this retrospective cohort study. Anticholinergic load was assessed by the Anticholinergic Risk Scale (ARS), and functional recovery was assessed by the Functional Independence Measure (FIM). The primary outcome was cognitive FIM (FIM-C) gain, but we also assessed the interaction of other putative factors identified from univariate analysis. Multivariate analyses were performed, adjusting for confounding factors. RESULTS AND DISCUSSION: We included 418 participants (171 males, 247 females) with a median age of 78 years (interquartile range, 72-84 years). Multiple regression analysis revealed that ARS change, length of stay, and epilepsy were independently and negatively correlated with cognitive FIM gain. Multiple logistic regression analysis indicated that the "Comprehension" and "Memory" items of the cognitive FIM gain were independently and negatively associated with anticholinergic load. WHAT IS NEW AND CONCLUSION: A causal relationship cannot be established, but increased ARS scores during hospitalization may predict limited cognitive functional improvement in geriatric patients after stroke. Alternatively, cognitive impairment may lead to increased use of anticholinergic drugs.

A red fluorophore comprising a borinate-containing xanthene analogue as a polyol sensor.

A xanthene derivative containing a borinate moiety emitted red fluorescence with a high quantum yield. The interaction between the borinate and a sugar molecule induced a fluorescence change based on the change in the HOMO-LUMO gap. The response was pH-resistant in a wide range. In addition, catechol quenched through photoinduced electron transfer. The red fluorescence and polyol binding ability of dyes will pave the way for new biological applications of chemical sensors.

A pre-operative predictive score for the outcome of eccentric rotational acetabular osteotomy in the treatment of acetabular dysplasia and early osteoarthritis of the hip in adults.

AIMS: The influence of identifiable pre-operative factors on the outcome of eccentric rotational acetabular osteotomy (ERAO) is unknown. We aimed to determine the factors that might influence the outcome, in order to develop a scoring system for predicting the prognosis for patients undergoing this procedure. PATIENTS AND METHODS: We reviewed 700 consecutive ERAOs in 54 men and 646 women with symptomatic acetabular dysplasia or early onset osteoarthritis (OA) of the hip, which were undertaken between September 1989 and March 2013. The patients' pre-operative background, clinical and radiological findings were examined retrospectively. Multivariate Cox regression analysis was performed using the time from the day of surgery to a conversion to total hip arthroplasty (THA) as an endpoint. A risk score was calculated to predict the prognosis for conversion to THA, and its predictive capacity was investigated. RESULTS: The congruity of the hip, age, the pre-operative minimum width of the joint space and range of abduction were identified as factors predicting conversion to THA. For three groups of patients (scoring 0 to 5, 6 to 7, and 8 to 9 points), the Kaplan-Meier event-free rates of survival at 15 years post-operatively for conversion to THA were 99.6%, 85.2% and 67.3%, respectively. CONCLUSION: These four pre-operative factors are easily measured and predict the prognosis for patients following ERAO. They may be used for decision making when offering surgical treatment to patients with acetabular dysplasia and early onset osteoarthritis. Cite this article: Bone Joint J 2016;98-B:1326-32.

Comparison of oncological safety between nipple sparing mastectomy and total mastectomy using propensity score matching.

INTRODCUTION: Although nipple sparing mastectomy (NSM) has attracted increased recognition as an alternative to traditional mastectomy approaches, its oncological safety is unclear. The purpose of this study was to compare the local recurrence rate between NSM and total mastectomy (TM). METHODS: Between 2003 and 2013, 121 and 557 patients with stage 0-III breast cancer underwent NSM and TM respectively. Multivariate Cox regression and propensity score models were used to compare the two groups. RESULTS: There was no significant difference in the five-year local recurrence rate between the NSM and TM groups (7.6% vs 4.9%, p=0.398). In multivariate analysis, NSM was not a risk factor for local recurrence (hazard ratio: 1.653, 95% confidence interval: 0.586-4.663, p=0.343). Propensity score matching found similar five-year local recurrence free survival rates between the two groups (92.3% vs 93.7%, p=0.655). CONCLUSIONS: Our results suggest that NSM may provide oncological safety comparable with mastectomy for carefully selected patients.