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1.
Appl Environ Microbiol ; 87(23): e0097721, 2021 11 10.
Article in English | MEDLINE | ID: mdl-34550782

ABSTRACT

In this study, we performed a year-long in situ incubation experiment on a common ferrous sulfide (Fe-S) mineral, pyrite, at the oxidative deep seafloor in the hydrothermal vent field in the Izu-Bonin arc, Japan, and characterized its microbiological and biogeochemical properties to understand the microbial alteration processes of the pyrite, focusing on Fe(II) oxidation. The microbial community analysis of the incubated pyrite showed that the domain Bacteria heavily dominated over Archaea compared with that of the ambient seawater, and Alphaproteobacteria and Gammaproteobacteria distinctively codominated at the class level. The mineralogical characterization by surface-sensitive Fe X-ray absorption near-edge structure (XANES) analysis revealed that specific Fe(III) hydroxides (schwertmannite and ferrihydrite) were locally formed at the pyrite surface as the pyrite alteration products. Based on the Fe(III) hydroxide species and proportion, we thermodynamically calculated the pH value at the pyrite surface to be pH 4.9 to 5.7, indicating that the acidic condition derived from pyrite alteration was locally formed at the surface against neutral ambient seawater. This acidic microenvironment at the pyrite surface might explain the distinct microbial communities found in our pyrite samples. Also, the acidity at the pyrite surface indicates that the abiotic Fe(II) oxidation rate was much limited at the pyrite surface kinetically, 3.9 × 103- to 1.6 × 105-fold lower than that in the ambient seawater. Moreover, nanoscale characterization of microbial biomolecules using carbon near-edge X-ray absorption fine-structure (NEXAFS) analysis showed that the sessile cells attached to pyrite excreted the acidic polysaccharide-rich extracellular polymeric substances at the pyrite surface, which can lead to the promotion of biogenic Fe(II) oxidation and pyrite alteration. IMPORTANCE Pyrite is one of the most common Fe-S minerals found in submarine hydrothermal environments. Previous studies demonstrated that the Fe-S mineral can be a suitable host for Fe(II)-oxidizing microbes in hydrothermal environments; however, the details of microbial Fe(II) oxidation processes with Fe-S mineral alteration are not well known. The spectroscopic and thermodynamic examination in the present study suggests that a moderately acidic pH condition was locally formed at the pyrite surface during pyrite alteration at the seafloor due to proton releases with Fe(II) and sulfidic S oxidations. Following previous studies, the abiotic Fe(II) oxidation rate significantly decreases with a decrease in pH, but the biotic (microbial) Fe(II) oxidation rate is not sensitive to the pH decrease. Thus, our findings clearly suggest that the pyrite surface is a unique microenvironment where abiotic Fe(II) oxidation is limited and biotic Fe(II) oxidation is more prominent than that in neutral ambient seawater.


Subject(s)
Ferric Compounds , Ferrous Compounds , Iron/chemistry , Seawater/microbiology , Sulfides/chemistry , Ferric Compounds/chemistry , Ferrous Compounds/chemistry , Japan , Minerals
2.
AJNR Am J Neuroradiol ; 42(2): 306-312, 2021 01.
Article in English | MEDLINE | ID: mdl-33361373

ABSTRACT

BACKGROUND AND PURPOSE: Obtaining information on invisible vasculature distal to the occlusion site helps to deploy a stent retriever safely during mechanical thrombectomy for large-vessel occlusion. It is essential to reduce the amount of contrast used for detecting the vessels distal to the occlusion site because acute ischemic stroke patients tend to have chronic kidney disease and patients with severe chronic kidney disease are at an increased risk of contrast-associated acute kidney injury. We assessed whether vessels distal to the occlusion site during acute ischemic stroke with large-vessel occlusion could be visualized on angiographic images using flat panel detector CT acquired following intra-arterial diluted contrast injection, compared with MRA findings. MATERIALS AND METHODS: Between May 2019 and January 2020, we enrolled 28 consecutive patients with large-vessel occlusions of the anterior circulation eligible for mechanical thrombectomy following MR imaging. The patients underwent CBV imaging using flat panel detector CT with an intra-arterial diluted contrast injection instead of intravenous injection. Flat panel detector CT angiographic images reconstructed from the same dataset were evaluated for image quality, collateral status of the MCA territory, and visualization of the vessels distal to the occlusion site. These findings were compared with MRA findings. RESULTS: Twenty-two patients were retrospectively examined. Flat panel detector CT angiographic image quality in 20 patients (91%) was excellent or good. The distal portion of the occluded vessel segment was visualized in 14 patients (70%), while the proximal portion of the segment adjacent to the occluded vessel in 3 (15%) was visualized. No visualization was observed in only 1 patient (5%) with no collateral supply. Flat panel detector CT angiographic images were shown to evaluate vessels distal to the occlusion site more accurately than MRA. CONCLUSIONS: In acute ischemic stroke with large-vessel occlusion, flat panel detector CT angiographic images could successfully visualize vessels distal to the occlusion site with a small amount of contrast material.


Subject(s)
Cerebral Angiography/methods , Computed Tomography Angiography/methods , Ischemic Stroke/diagnostic imaging , Ischemic Stroke/surgery , Thrombectomy/methods , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Retrospective Studies , Surgery, Computer-Assisted/methods
3.
Sci Rep ; 7(1): 5993, 2017 07 20.
Article in English | MEDLINE | ID: mdl-28729553

ABSTRACT

Recently, perpendicular magnetic anisotropy (PMA) and its voltage control (VC) was demonstrated for Cr/Fe/MgO. In this study, we shed light on the origin of large voltage-induced anisotropy change in Cr/Fe/MgO. Analysis of the chemical structure of Cr/Fe/MgO revealed the existence of Cr atoms in the proximity of the Fe/MgO interface, which can affect both magnetic anisotropy (MA) and its VC. We showed that PMA and its VC can be enhanced by controlled Cr doping at the Fe/MgO interface. For Cr/Fe (5.9 Å)/Cr (0.7 Å)/MgO with an effective PMA of 0.8 MJ/m3, a maximum value of the voltage-controlled magnetic anisotropy (VCMA) effect of 370 fJ/Vm was demonstrated due to Cr insertion.

4.
J Anim Breed Genet ; 134(5): 373-382, 2017 Oct.
Article in English | MEDLINE | ID: mdl-28470817

ABSTRACT

Meat composition in beef is related to eating quality and food functionality. Genetic parameters for several meat compositions including free amino acid, peptide and sugar, however, remain poorly described. In this study, we estimated genetic parameters for 51 meat components, including free amino acids, peptides, sugars and fatty acid compositions, and two carcase traits in 1,354 heifers and 1,797 steers of Japanese Black cattle. Heritability estimates were generally equivalent to or moderately greater than those in previous studies of this breed. Genetic correlations between free amino acids, peptides and sugars and carcase traits were often negative, suggesting a trade-off between traits. Using two-trait animal models that treat records from the two sexes as different traits, we estimated sex-specific heritabilities and cross-sex genetic correlations which indicate the sex differences in genetic architecture. In these analyses, 12 traits showed significant heritability differences between sexes and cross-sex genetic correlations occasionally deviated from unity. These results could be used to inform future breeding schemes and investigations of the genetic architecture of meat compositions in beef.


Subject(s)
Cattle/genetics , Genetic Association Studies/veterinary , Meat/analysis , Quantitative Trait, Heritable , Amino Acids/analysis , Animals , Breeding , Fatty Acids/analysis , Female , Food Quality , Male , Peptides/analysis , Phenotype , Sex Factors , Sugars/analysis
5.
Clin Radiol ; 72(10): 904.e1-904.e10, 2017 Oct.
Article in English | MEDLINE | ID: mdl-28522258

ABSTRACT

AIM: To investigate the usefulness of high-resolution 3 T magnetic resonance imaging (MRI) for the evaluation of traumatic and degenerative triangular fibrocartilage complex (TFCC) abnormalities among three groups: patients presenting with wrist pain who were (a) younger than age 50 years or (b) age 50 or older (PT<50 and PT≥50, respectively), and (c) asymptomatic controls who were younger than age 50 years (AC). MATERIALS AND METHODS: High-resolution 3 T MRI was evaluated retrospectively in 96 patients, including 47 PT<50, 38 PT≥50, and 11 AC. Two board-certified radiologists reviewed the MRI images independently. MRI features of TFCC injury were analysed according to the Palmer classification, and cartilage degeneration around the TFCC was evaluated using the Outerbridge classification. Differences in MRI findings among these groups were detected using chi-square test. Cohen's kappa was calculated to assess interobserver and intra-observer reliability. RESULTS: The incidence of Palmer class 1A, 1C and 1D traumatic TFCC injury was significantly (p<0.05) higher in PT≥50 than in PT<50 (class 1A: 47.4% versus 27.7%, class 1C: 31.6% versus 12.8%, and class 1D: 21.1% versus 2.1%). Likewise, MRI findings of TFCC degeneration were observed more frequently in PT≥50 than in PT<50 (p<0.01). Outerbridge grade 2 or higher cartilage degeneration was significantly (p<0.01) more frequently seen in PT≥50 than in PT<50 (55.3% versus 17% in the lunate, 28.9% versus 4.3% in the triquetrum, 73.7% versus 12.8% in the ulna). CONCLUSION: High-resolution wrist MRI at 3 T enables detailed evaluation of TFCC traumatic injury and degenerative changes using the Palmer and Outerbridge classifications, with good or excellent interobserver and intra-observer reliability.


Subject(s)
Cartilage Diseases/diagnostic imaging , Magnetic Resonance Imaging/methods , Triangular Fibrocartilage/diagnostic imaging , Adult , Age Factors , Aged , Cartilage Diseases/pathology , Female , Humans , Male , Middle Aged , Reproducibility of Results , Triangular Fibrocartilage/injuries , Triangular Fibrocartilage/pathology , Wrist Injuries/diagnostic imaging , Wrist Injuries/pathology , Wrist Joint/pathology , Young Adult
6.
Phys Chem Chem Phys ; 19(12): 8188-8193, 2017 Mar 22.
Article in English | MEDLINE | ID: mdl-28263337

ABSTRACT

In this work, we investigated the temperature dependence of interface exchange coupling in an Ir-doped Fe2O3/Co system with variations in the Ir-Fe2O3 thickness. Low-temperature perpendicular exchange bias was observed in the samples with an Ir-Fe2O3 thickness of 5 nm or less, when it cooled from 360 K in an external magnetic field of 1 T perpendicular to the sample surface. For 5 nm-thick Ir-Fe2O3, a maximum exchange bias value of 1200 Oe was obtained at 200 K. This is the first report on perpendicular exchange bias of an Fe2O3 thin film coupled with a ferromagnet. Enhancements to the Morin temperature and the magnetic anisotropy of Fe2O3 caused by lattice strain, Ir doping, and the finite-size scaling effect, as well as the high quality (good crystal orientation, small roughness, etc.) of the Fe2O3 film fabricated by our process, are considered to be mostly responsible for the perpendicular exchange bias obtained.

7.
Obes Sci Pract ; 2(2): 180-188, 2016 Jun.
Article in English | MEDLINE | ID: mdl-27812383

ABSTRACT

BACKGROUND: Although the serum adiponectin level is inversely correlated to body mass index and closely associated with obesity and related diseases, neither the impact of weight loss on the adiponectin level nor other factors that might influence the adiponectin level during weight loss intervention are well documented. OBJECTIVE: The objective of the study is to assess the change in the serum adiponectin level during weight loss intervention and to determine if sleep parameters affect the serum adiponectin level. METHODS: Ninety women with overweight or obesity aged 25 to 65 years completed a 7-month cognitive behavioural therapy based weight loss intervention that included dieting, exercise and stress management. Serum adiponectin level, body fat percent, symptoms of depression and anxiety and objective sleep parameters, assessed by actigraphy, were measured at baseline and at the end of the intervention. RESULTS: The serum adiponectin level was significantly increased after the weight loss intervention (P < 0.001). In a multiple regression analysis, the change of the adiponectin level was positively associated with the magnitude of body fat loss (ß = -0.317, P < 0.001) and an increase of sleep minutes (ß = 0.210, P = 0.043). CONCLUSION: An increase in objective sleep duration was related to a significantly increased serum adiponectin level independently of the change of body fat during the weight loss intervention.

8.
Transplant Proc ; 48(3): 905-9, 2016 Apr.
Article in English | MEDLINE | ID: mdl-27234764

ABSTRACT

BACKGROUND: The purpose of this study was to present our experience with robot-assisted radical prostatectomy (RARP) for localized prostate cancer in renal transplant recipients (RTRs) and to determine the feasibility and efficacy of RARP in these patients. METHODS: We retrospectively reviewed the medical records of 236 patients who underwent RARP for localized prostate cancer at our institution between August 2011 and July 2015 and identified 3 patients who were RTRs. We reviewed the available clinical data of the 3 patients. RESULTS: All patients underwent RARP successfully without any major complications. The mean operation time was 162 minutes (range, 127-195 minutes). The mean estimated blood loss was 52 mL (range, 30-75 mL); therefore, the patients did not need any perioperative blood transfusion. In all cases, graft function, as determined according to the serum creatinine level, was stable during and after the operation. Pathological examination showed negative surgical margins with organ-confined disease in all patients. CONCLUSIONS: We reported 3 RTRs with localized prostate cancer who were treated with RARP. RARP might be a feasible and effective minimally invasive technique for the treatment of localized prostate cancer in carefully selected RTRs.


Subject(s)
Adenocarcinoma/surgery , Kidney Failure, Chronic/surgery , Kidney Transplantation , Prostatectomy , Prostatic Neoplasms/surgery , Robotic Surgical Procedures , Adenocarcinoma/complications , Adenocarcinoma/pathology , Aged , Humans , Japan , Kidney Failure, Chronic/complications , Kidney Failure, Chronic/pathology , Male , Middle Aged , Operative Time , Prostatic Neoplasms/complications , Prostatic Neoplasms/pathology , Retrospective Studies
9.
Transplant Proc ; 48(3): 910-3, 2016 Apr.
Article in English | MEDLINE | ID: mdl-27234765

ABSTRACT

BACKGROUND: In young patients with localized prostate cancer, radical prostatectomy is the treatment of choice in the general population. Radiotherapy, such as low-dose rate (LDR) brachytherapy or intensity-modulated radiotherapy, is a viable alternative as well. However, in transplant patients, irradiation is not proposed as often as it is in healthy adults because of the risk of post-radiation ureteral stenosis and gastrointestinal toxicity as the result of fragile tissue. The objective of the study was to assess the efficacy and feasibility of LDR brachytherapy for prostate cancer in renal transplant recipients (RTRs). METHODS: Between May 2007 and December 2014, all patients who had undergone LDR brachytherapy for clinically localized prostate cancer at our institution were retrospectively identified (n = 203). Of these patients, 2 had a history of renal transplantation. We reviewed all available clinical data retrospectively. One patient had a functioning graft and the other had re-started hemodialysis 7 years after the transplantation. RESULTS: The mean time from renal transplantation to prostate cancer diagnosis was 16 years. The mean follow-up after seed implantation was 45 months. There were no peri-operative complications after seed implantation. The 2 patients remained free of prostate-specific antigen progression during the follow-up period. The renal function of the patient with a functioning graft, as measured by serum creatinine, was stable during and after the operation. CONCLUSIONS: LDR brachytherapy is technically feasible and acceptable as a minimally invasive treatment in carefully selected RTRs with localized prostate cancer. This treatment should be considered a suitable option for RTRs with localized prostate cancer.


Subject(s)
Adenocarcinoma/radiotherapy , Brachytherapy , Kidney Failure, Chronic/surgery , Kidney Transplantation , Prostatic Neoplasms/radiotherapy , Adenocarcinoma/complications , Adenocarcinoma/pathology , Aged , Feasibility Studies , Humans , Kidney Failure, Chronic/complications , Kidney Failure, Chronic/pathology , Male , Middle Aged , Prostatic Neoplasms/complications , Prostatic Neoplasms/pathology , Retrospective Studies , Treatment Outcome
10.
Transplant Proc ; 48(3): 914-7, 2016 Apr.
Article in English | MEDLINE | ID: mdl-27234766

ABSTRACT

BACKGROUND: In transplant patients with localized prostate cancer, irradiation is not proposed as often as it is in healthy adults because of the post-radiation risks, such as ureteral stenosis and gastrointestinal toxicity as the result of fragile tissue. The objective of the study was to analyze the efficacy and feasibility of intensity-modulated radiation therapy (IMRT) for prostate cancer in renal transplant recipients (RTRs). METHODS: Between May 2005 and December 2014, all patients who had undergone IMRT for clinically localized prostate cancer at our institution were retrospectively identified (n = 365). Of these patients, 2 had a history of renal transplantation. We reviewed all available clinical data. One patient had a functioning graft and the other had restarted hemodialysis 7 years after the transplantation. RESULTS: The mean time from renal transplantation to prostate cancer diagnosis was 11 years. The mean follow-up after irradiation was 43 months. The 2 patients remain free of prostate-specific antigen progression. There was no severe acute and chronic genitourinary and gastrointestinal toxicity. Renal function of the patient with a functioning graft as measured by serum creatinine was stable during and after the irradiation. CONCLUSIONS: IMRT is feasible and acceptable as a minimally invasive treatment in the carefully selected RTRs with localized prostate cancer. This treatment should be considered a good option for RTRs with localized prostate cancer.


Subject(s)
Adenocarcinoma/radiotherapy , Kidney Failure, Chronic/surgery , Kidney Transplantation , Prostatic Neoplasms/radiotherapy , Radiotherapy, Intensity-Modulated , Adenocarcinoma/complications , Adenocarcinoma/pathology , Aged , Feasibility Studies , Humans , Kidney Failure, Chronic/complications , Kidney Failure, Chronic/pathology , Male , Prostatic Neoplasms/complications , Prostatic Neoplasms/pathology , Retrospective Studies , Time Factors , Treatment Outcome
11.
Am J Transplant ; 16(3): 886-96, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26555133

ABSTRACT

ABO-incompatible living kidney transplantation (ABO-ILKT) has steadily become more widespread. However, the optimal immunosuppressive regimen for ABO-ILKT remains uncertain. We aimed to determine the longitudinal changes in the outcomes from ABO-ILKT compared with those from ABO-compatible living kidney transplantation (ABO-CLKT) over the last 25 years. Of 1195 patients who underwent living kidney transplantations (LKT) at our institute between 1989 and 2013, 1032-including 247 ABO-ILKT and 785 ABO-CLKT cases-were evaluated for graft survival, patient survival, infectious adverse events, and renal function. The patients were divided into four groups according to the transplantation era and ABO-compatibility. In the past decade, ABO-ILKT and ABO-CLKT recipients yielded almost equivalent outcomes with respect to the 9-year graft survival rates, which were 86.9% and 92.0%, respectively (hazard ratio [HR] 1.38, 95% confidence interval [CI] 0.59-3.22, p = 0.455). The graft survival rate for ABO-ILKT conducted between 2005 and 2013 was better than that for ABO-ILKT conducted between 1998 and 2004 (HR 0.30, 95% CI 0.13-0.72, p = 0.007). ABO-ILKT recipients showed substantial improvements in the graft survival rate over time. Graft survival was almost identical over the past decade, regardless of ABO-incompatibility. Currently, ABO-ILKT is an acceptable treatment for patients with end-stage renal disease.


Subject(s)
ABO Blood-Group System/immunology , Blood Group Incompatibility/immunology , Desensitization, Immunologic/methods , Kidney Failure, Chronic/surgery , Kidney Transplantation , Adult , Female , Follow-Up Studies , Glomerular Filtration Rate , Graft Survival , Humans , Immunosuppressive Agents/therapeutic use , Kidney Function Tests , Living Donors , Male , Middle Aged , Prognosis , Prospective Studies , Retrospective Studies , Risk Factors
12.
J Fish Dis ; 39(6): 667-72, 2016 Jun.
Article in English | MEDLINE | ID: mdl-26096292

ABSTRACT

Foodborne disease outbreaks caused by raw olive flounders (Paralichthys olivaceus) parasitized with Kudoa septempunctata have been reported in Japan. Origins of olive flounders consumed in Japan vary, being either domestic or imported, and aquaculture-raised or natural. Although it is unknown whether different sources are associated with different outcomes, it is desirable to identify whether this is the case by determining whether unique K. septempunctata strains occur and if so, whether some are associated with foodborne illness. We here developed an intraspecific genotyping method, using the sequence variation of mitochondrial genes. We collected olive flounder samples from foodborne disease outbreaks, domestic fish farms or quarantine offices and investigated whether K. septempunctata genotype is associated with pathogenicity or geographic origin. The 104 samples were classified into three genotypes, ST1, ST2 and ST3. Frequency of symptomatic cases differed by genotypes, but the association was not statistically significant. Whereas K. septempunctata detected from aquaculture-raised and natural fish from Japan were either ST1 or ST2, those from fish inspected at quarantine from Korea to Japan were ST3. Our method can be applied to phylogeographic analysis of K. septempunctata and contribute to containing the foodborne disease. The genotype database is hosted in the PubMLST website (http://pubmlst.org/kseptempunctata/).


Subject(s)
Fish Diseases/epidemiology , Foodborne Diseases/epidemiology , Myxozoa/genetics , Parasitic Diseases, Animal/epidemiology , Seafood/poisoning , Animals , Fish Diseases/parasitology , Flatfishes , Foodborne Diseases/parasitology , Genetic Variation , Genome, Mitochondrial , Geography , Humans , Incidence , Japan/epidemiology , Myxozoa/classification , Parasitic Diseases, Animal/parasitology , Republic of Korea/epidemiology , Seasons , Sequence Analysis, DNA/veterinary
13.
Nutr Diabetes ; 4: e144, 2014 Oct 27.
Article in English | MEDLINE | ID: mdl-25347608

ABSTRACT

BACKGROUND: Sleep has been identified as having an influence on the success of weight-loss interventions; however, knowledge of the mechanisms and the extent to which sleep disturbances affect the magnitude of weight reduction is inconclusive. OBJECTIVE: To determine if sleep duration and quality can predict the magnitude of weight reduction in a weight-loss intervention program for overweight and obese women. METHODS: Ninety overweight and obese women aged 25-65 years completed the 7-month weight-loss phase of our weight-loss intervention. Sleep duration and quality were evaluated before the intervention by the Pittsburg Sleep Quality Index (PSQI), a self-report questionnaire, and by actigraphy. Serum levels of ghrelin, leptin, cortisol and insulin also were measured at baseline. Insulin resistance was measured by the homeostasis model assessment of insulin resistance (HOMA-IR). RESULTS: The mean reduction rate of body mass index (BMI) after the intervention was 13.6%. Multiple linear regression revealed that the number of wake episodes (WEs) per night had a significant relationship with the reduction of BMI even after adjusting for other clinical variables (ß=-0.341, P=0.001). The participants with five or more WEs per night (high-WE group) had a significantly lower reduction in BMI compared with those with fewer than five (normal-WE group), after adjusting for confounding variables. In contrast, the PSQI-assessed parameters, reflecting the subjective assessments of sleep quality and duration, failed to detect an association with the reduction in BMI. Baseline HOMA-IR was significantly higher in the high-WE group than in the normal-WE group after adjusting for confounding variables. CONCLUSIONS: Higher sleep fragmentation, as manifested by the increased number of WEs, predicts a lower magnitude of weight reduction in persons participating in weight-loss programs.

14.
Lupus ; 23(7): 703-6, 2014 Jun.
Article in English | MEDLINE | ID: mdl-22187162

ABSTRACT

We report on an 11-year-old girl who developed steroid-resistant nephrotic syndrome (NS) at the onset of systemic lupus erythematosus (SLE), and clinical and renal histological findings suggested that her NS would be associated with SLE-related podocytopathy. Although initial treatment with intravenous pulse methylprednisolone was ineffective, following treatment with cyclosporine and an angiotensin receptor blocker was effective for her nephrotic proteinuria. She had developed posterior reversible encephalopathy syndrome (PRES), and mycophenolate mofetil (MMF) was started instead of cyclosporine. At present, 45 months after the onset, she is in remission of both NS and SLE. This case indicates that NS associated with SLE-related podocytopathy should be included in the spectrum of glomerulopathy accompanying SLE, also in the pediatric population.


Subject(s)
Glucocorticoids/therapeutic use , Lupus Erythematosus, Systemic/complications , Methylprednisolone/therapeutic use , Nephrotic Syndrome/drug therapy , Nephrotic Syndrome/etiology , Child , Cyclosporine , Drug Resistance , Female , Humans
16.
Nat Mater ; 13(1): 50-6, 2014 Jan.
Article in English | MEDLINE | ID: mdl-24141450

ABSTRACT

Highly sensitive microwave devices that are operational at room temperature are important for high-speed multiplex telecommunications. Quantum devices such as superconducting bolometers possess high performance but work only at low temperature. On the other hand, semiconductor devices, although enabling high-speed operation at room temperature, have poor signal-to-noise ratios. In this regard, the demonstration of a diode based on spin-torque-induced ferromagnetic resonance between nanomagnets represented a promising development, even though the rectification output was too small for applications (1.4 mV mW(-1)). Here we show that by applying d.c. bias currents to nanomagnets while precisely controlling their magnetization-potential profiles, a much greater radiofrequency detection sensitivity of 12,000 mV mW(-1) is achievable at room temperature, exceeding that of semiconductor diode detectors (3,800 mV mW(-1)). Theoretical analysis reveals essential roles for nonlinear ferromagnetic resonance, which enhances the signal-to-noise ratio even at room temperature as the size of the magnets decreases.

17.
J Appl Phys ; 113(17): 17D711, 2013 May 07.
Article in English | MEDLINE | ID: mdl-23633724

ABSTRACT

In this study, we fabricated a Cr2O3 (0001) film without and with a Pt buffer layer and investigated its effect on perpendicular exchange coupling in a Cr2O3/Co3Pt interface. The results showed that the exchange bias field (µ0Hex) and blocking temperature (TB) of a Cr2O3 film without and with Pt were very different. The Cr2O3 film without Pt had a lower µ0Hex of 176 Oe and a lower TB of 75 K, whereas that with Pt had a higher µ0Hex of 436 Oe and a higher TB of 150 K. We discussed this difference in µ0Hex and TB values based on collinear/non-collinear coupling in a ferromagnetic and antiferromagnetic interface using Meiklejohn and Bean's exchange anisotropy model.

18.
Transplant Proc ; 44(3): 680-3, 2012 Apr.
Article in English | MEDLINE | ID: mdl-22483467

ABSTRACT

OBJECTIVES: We expect that if chronic renal failure (CRF) is improved after renal transplantation (RTx), dialysis osteopathy bone lesions would also recover to normal. Nevertheless, it is controversial whether bone lesions really improve after RTx. In this study, we evaluated whether pathological dialysis osteopathy improved after RTx. MATERIALS AND METHODS: The 84 patients who had undergone living related RTx had also undergone a bone biopsy (Bx) since January 2004, including 13 (16.0%) with a diagnosis of aplastic osteopathy. They included 7 men and 6 women. The average hemodialysis (HD) period was 40.3 months. The immunosuppression was tacrolimus (FK); mycophenalate mofetil (MMF) and steroid. We examined Ca, P, intact-PTH (i-PTH), metabolic bone markers, and bone density (DXA) before and 1 year after RTx. In addition, a Bx was performed after having osteal labeling twice before Bx. In addition 2 cases (15.3%) also underwent a Bx after RTx. RESULTS: All cases survive with well functioning renal grafts. The mean levels of Ca and P before RTx were 8.7 mg/mL and 6.6 mg/dL, respectively. The mean i-PTH level was 137.8 pg/mL before RTx and of alkaline phosphatase (ALP) was 202.1 U/L before RTx. The total density and % age match of DXA before RTx averaged 398.7 mg/ccm and 96.7%, respectively. The mean bone volume fraction (BV/TV: Bone Volume/Tissue Volume) before RTx was 17.2%. The mean osteoid volume (OV/TV) before RTx was 2.7%. The mean fibrosis volume (Fb.V/TV) before RTx was 0%. The mean bone formation rate (BFR/BV) before RTx was 2.1 %/y. Two cases were also pathologically diagnosed as renal osteodystrophy at 1 year after RTx: 1 case was mixed type, and another was osteomalacia, which was accompanied by a lumbar compression fracture (Fx) during the clinical course. CONCLUSIONS: Bone metabolism in patients with aplastic ROD histologically improved at 1 year after RTx, presumably due to good renal transplant function. However, it is unknown whether both hypophosphatemia and decrease of FGF-23 improved bone However, patients with aplastic ROD were not completely normalized histologically at 1 year after RTx.


Subject(s)
Bone Diseases/pathology , Kidney Transplantation , Adult , Female , Fibroblast Growth Factor-23 , Humans , Immunosuppressive Agents/administration & dosage , Male , Middle Aged , Renal Dialysis , Treatment Outcome
19.
Water Sci Technol ; 65(6): 1102-8, 2012.
Article in English | MEDLINE | ID: mdl-22378009

ABSTRACT

A submerged flat metal MBR (membrane bioreactor) was used to treat synthetic domestic sewage in this study. The experiment was continued for 270 days and ran under two modes as AMBR (aerobic membrane bioreactor) and A/O-MBR (anoxic/aerobic membrane bioreactor) at a permeate flux of 0.4-1 m³/(m² d). PVA (polyvinyl alcohol) gel beads were added to the aeration tank with a volume ratio of 10% at the end of the A/O-MBR mode. The mean COD and TN removal efficiencies achieved 96.69 and 32.12% under the AMBR mode, and those were 92.17 and 72.44% under the A/O-MBR mode, respectively. SND (simultaneous nitrification and denitrification) occurred at high MLSS (mixed liquor suspended solids) concentration. The metal membranes reduced effluent COD during filtration. The system ran stably for 115 days at a permeate flux of 0.8-1 m³/(m² d) without changing membranes under the AMBR mode, but the membrane filterability decreased gradually under high MLSS or A/O-MBR mode, and the addition of PVA worsened the membrane filterability on the contrary. PSD (particle size distribution) and sludge fractions had evident influence on membrane fouling. The main fouling mechanism was cake formation under the AMBR mode, and that was pore blocking under the A/O-MBR mode.


Subject(s)
Bioreactors , Membranes, Artificial , Sewage , Water Purification/instrumentation , Aerobiosis , Anaerobiosis , Filtration/instrumentation , Filtration/methods , Nitrogen/chemistry , Phosphorus/chemistry , Time Factors , Water Pollutants, Chemical/chemistry , Water Purification/methods
20.
Eat Weight Disord ; 17(1): e1-8, 2012 Mar.
Article in English | MEDLINE | ID: mdl-21997338

ABSTRACT

OBJECTIVE: To investigate the outcome of Japanese anorexia nervosa (AN) patients who were treated with the standard Japanese inpatient therapy. METHOD: Of the 88 female AN patients treated with our inpatient therapy between January 1997 and December 2002, 67 (76.1%) who agreed to cooperate in this study were assessed by the Global Clinical Score (GCS) at admission and follow-up, 6.3±1.8 years after discharge. Their clinical characteristics at admission and discharge were also examined. RESULTS: Four (6.0%) patients had died before follow-up. BMI was significantly increased during inpatient therapy. At follow-up, excellent, much improved, symptomatic, and poor outcomes on GCS were 57.1%, 14.3%, 14.3% and 14.3%, respectively. Younger age at admission and larger BMI at discharge were significantly associated with a better outcome. DISCUSSION: This study shows the potential for the use of this method for the treatment of AN patients in countries without specialized eating disorder units.


Subject(s)
Anorexia Nervosa/therapy , Cognitive Behavioral Therapy/methods , Inpatients , Adolescent , Adult , Age Factors , Anorexia Nervosa/mortality , Body Mass Index , Female , Follow-Up Studies , Hospital Units , Humans , Internal Medicine , Japan/epidemiology , Risk Factors , Treatment Outcome
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