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1.
Nat Commun ; 13(1): 1817, 2022 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-35361763

RESUMO

Magnetic refrigeration (MR) is a key technique for hydrogen liquefaction. Although the MR has ideally higher performance than the conventional gas compression technique around the hydrogen liquefaction temperature, the lack of MR materials with high magnetic entropy change in a wide temperature range required for the hydrogen liquefaction is a bottle-neck for practical applications of MR cooling systems. Here, we show a series of materials with a giant magnetocaloric effect (MCE) in magnetic entropy change (-∆Sm > 0.2 J cm-3K-1) in the Er(Ho)Co2-based compounds, suitable for operation in the full temperature range required for hydrogen liquefaction (20-77 K). We also demonstrate that the giant MCE becomes reversible, enabling sustainable use of the MR materials, by eliminating the magneto-structural phase transition that leads to deterioration of the MCE. This discovery can lead to the application of Er(Ho)Co2-based alloys for the hydrogen liquefaction using MR cooling technology for the future green fuel society.

2.
Sci Technol Adv Mater ; 22(1): 449-460, 2021 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-34211334

RESUMO

To realize a sustainable society, 'green technology' with low (or even zero) CO2 emissions is required. A key material in such technology is a permanent magnet because it is utilized for electric-power conversion in several applications including electric vehicles (EVs), hybrid EVs (HEVs), and turbines for wind power generation. To realize highly efficient electric-power conversion, a stronger permanent magnet than Nd-Fe-B is necessary. One potential candidate is a Fe-rich SmFe12-based compound with a ThMn12 structure. In this paper, the phase stability, structure, and intrinsic and extrinsic magnetic properties in both film and bulk forms are reviewed. Based on these results, a possible way to realize a strong SmFe12-based permanent magnet in bulk form is discussed.

3.
Phys Rev Lett ; 126(23): 236801, 2021 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-34170165

RESUMO

Spin-charge conversion via spin-orbit interaction is one of the core concepts in the current spintronics research. The efficiency of the interconversion between charge and spin current is estimated based on Berry curvature of Bloch wave function in the linear-response regime. Beyond the linear regime, nonlinear spin-charge conversion in the higher-order electric field terms has recently been demonstrated in noncentrosymmetric materials with nontrivial spin texture in the momentum space. Here, we report the observation of the nonlinear charge-spin conversion in a nominally centrosymmetric oxide material SrIrO_{3} by breaking inversion symmetry at the interface. A large second-order magnetoelectric coefficient is observed at room temperature because of the antisymmetric spin-orbit interaction at the interface of Dirac semimetallic bands, which is subject to the symmetry constraint of the substrates. Our study suggests that nonlinear spin-charge conversion can be induced in many materials with strong spin-orbit interaction at the interface by breaking the local inversion symmetry to give rise to spin splitting in otherwise spin degenerate systems.

4.
Sci Rep ; 10(1): 19191, 2020 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-33154530

RESUMO

Orexins are originally characterized as orexigenic hypothalamic neuropeptides in mammals. Subsequent studies found orexin to be expressed and perform pleiotropic functions in multiple tissues in mammals. In avian (non-mammalian) species, however, orexin seemed to not affect feeding behavior and its physiological roles are poorly understood. Here, we provide evidence that orexin and its related receptors are expressed in chicken hepatocytes. Double immunofluorescence staining showed that orexin is localized in the ER, Golgi, and in the lysosomes in LMH cells. Brefeldin A treatment reduced orexin levels in the culture media, but increased it in the cell lysates. Administration of recombinant orexins upregulated the expression of orexin system in the liver of 9-day old chicks, but did not affect feed intake. Recombinant orexins increased fatty acid synthase (FASN) protein levels in chicken liver, activated acetyl-CoA carboxylase (ACCα), and increased FASN, ATP citrate lyase(ACLY), and malic enzyme (ME) protein expression in LMH cells. Blockade ERK1/2 activation by PD98059 attenuated these stimulating effects of orexin on lipogenic factors. Overexpression of ERK1/2 increased the expression of lipogenic genes, and orexin treatment induced the phosphorylated levels of ERK1/2Thr202/Tyr204, but not that of p38 Thr180/Tyr182 or JNK1/2 Thr183/Tyr185 in chicken liver and LMH cells. Taken together, this is the first report evidencing that orexin is expressed and secreted from chicken hepatocytes, and that orexin induced hepatic lipogenesis via activation of ERK1/2 signaling pathway.


Assuntos
Lipogênese/fisiologia , Fígado/metabolismo , Sistema de Sinalização das MAP Quinases/fisiologia , Orexinas/metabolismo , Acetil-CoA Carboxilase/metabolismo , Animais , Brefeldina A/farmacologia , Galinhas , Ingestão de Alimentos/fisiologia , Ácido Graxo Sintases/metabolismo , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Lipogênese/efeitos dos fármacos , Fígado/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Malato Desidrogenase/metabolismo , Orexinas/genética , Fosforilação/efeitos dos fármacos , Inibidores da Síntese de Proteínas/farmacologia , Regulação para Cima/efeitos dos fármacos
5.
Rev Sci Instrum ; 91(4): 043304, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32357747

RESUMO

The energy spreads of ion beams generated from a penning ionization gauge-type ion source with electromagnets were measured using a parallel electrostatic analyzer. The ion source was developed to be installed in a mega-electron volt (MeV) compact ion microbeam system. A gaseous ion beam of expectedly high brightness and narrow energy spread was generated from the ion source to form a microbeam. To produce such an ion beam, a high-density plasma with a small volume was generated using a strong magnetic field in the ion source. The beam energy spread width was of particular importance because it forms an ion microbeam by reducing the chromatic aberration at a focusing lens. In this report, the energy spread was investigated by changing the parameters of the ion source, e.g., extraction voltage, excitation current of electromagnets, vacuum, and anode voltage. The investigation showed that spread widths are influenced by the extraction voltage, vacuum, and anode voltage. The minimum width of ∼5.0 ± 0.1 eV was obtained at a beam energy of 200 eV. This value is acceptable for the MeV compact ion microbeam system.

6.
Eur J Neurol ; 26(9): 1219-1225, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31002446

RESUMO

BACKGROUND AND PURPOSE: The association between an increased supraventricular ectopic beat (SVEB) and subclinical cerebrovascular disease remains unclear. Given the emerging concept that an increased SVEB is a marker of atrial cardiomyopathy or atherosclerosis burden, we sought to determine whether excessive supraventricular ectopic activity (ESVEA) is associated with a higher burden of subclinical cerebrovascular disease in the middle-aged to older cohort with neither apparent stroke nor atrial fibrillation. METHODS: We conducted a cross-sectional population-based study of 462 men (mean age, 68.1 years) who underwent 24-h Holter electrocardiography and brain magnetic resonance imaging. ESVEA was defined as the presence of >10 SVEBs/h. Subclinical cerebrovascular diseases were defined as silent brain infarct (SBI), white matter hyperintensity (WMH) and intracranial atherosclerotic stenosis (ICAS). The association of ESVEA with the presence of subclinical cerebrovascular diseases was adjusted for potential confounding covariates. RESULTS: A total of 88 (19.0%) participants had ESVEA and 81 (17.5%), 91 (19.7%) and 109 (23.6%) had SBI, WMH and ICAS, respectively. In multivariable-adjusted Poisson regression with robust error variance, ESVEA was associated with the presence of WMH (relative risk, 1.58; 95% confidence interval, 1.06-2.36) and ICAS (relative risk, 1.49; 95% confidence interval, 1.02-2.18), but not with that of SBI (relative risk, 1.32; 95% confidence interval, 0.86-2.01). These associations were consistent when the graded distributions of subclinical cerebrovascular diseases were applied as outcomes in ordinal logistic regression. CONCLUSIONS: The ESVEA was independently associated with higher burdens of WMH and ICAS. This suggests that increased SVEBs might improve risk stratification of individuals at high risk of subclinical cerebrovascular disease and consequently apparent ischaemic stroke.


Assuntos
Infarto Encefálico/epidemiologia , Cardiomiopatias/epidemiologia , Arteriosclerose Intracraniana/epidemiologia , Leucoaraiose/epidemiologia , Idoso , Infarto Encefálico/diagnóstico por imagem , Cardiomiopatias/diagnóstico , Comorbidade , Estudos Transversais , Eletrocardiografia Ambulatorial , Humanos , Arteriosclerose Intracraniana/diagnóstico por imagem , Leucoaraiose/diagnóstico por imagem , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Acidente Vascular Cerebral/fisiopatologia
7.
J Clin Pharm Ther ; 43(5): 675-681, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29679392

RESUMO

WHAT IS KNOWN AND OBJECTIVE: For analysis of blood concentrations of everolimus, many hospital laboratories use either latex agglutination turbidimetric immunoassay (LTIA) or electrochemiluminescence immunoassay (ECLIA). However, no studies have compared both immunoassay methods under the same conditions. Accordingly, in this study, we compared everolimus blood concentrations obtained by LTIA and ECLIA in renal transplant patients. METHODS: Blood samples (n = 230) from 60 renal transplant patients (19 female and 41 male) were evaluated using both immunoassays. Subsequently, we switched the assay for detection of everolimus blood concentrations from LTIA to ECLIA as a clinical application. Three quality control (QC) samples for LTIA were analysed using ECLIA, and 3 QC samples for ECLIA were analysed using LTIA. RESULTS: The Deming regression of ECLIA versus LTIA generated the following parameters: slope, 1.0067 and intercept, 1.7489 ng/mL, in the analysis of 230 samples. Bland-Altman analysis showed an average positive bias of 1.73 ng/mL between ECLIA and LTIA. When the clinical apparatus was switched from LTIA to ECLIA, the average everolimus blood concentration assayed by LTIA before switching was 3.57 ng/mL, whereas that by ECLIA after switching in the same patients taking the same daily dose (mean: 1.43 mg/day) was 5.85 ng/mL. The QCs assayed using LTIA were lower by an average of 67.3% (range: 55.8%-79.5%) for ECLIA, and in the same 230 samples from patients, the everolimus blood concentrations assayed by LTIA were lower by an average of 67.4% (range: 37.1%-114.5%) of ECLIA. WHAT IS NEW AND CONCLUSION: Analysis of everolimus concentrations by immunoassays with high precision and accuracy is required to ensure long-term survival of transplant recipients. Although the concentrations of QCs and calibrators of everolimus in LTIA were previously corrected to 70% concentration because of cross-reactivity with everolimus metabolites, these adjustments may need to be reviewed.


Assuntos
Aglutinação/efeitos dos fármacos , Everolimo/sangue , Imunoensaio/métodos , Imunossupressores/sangue , Imunoturbidimetria/métodos , Látex/imunologia , Testes Diagnósticos de Rotina/métodos , Monitoramento de Medicamentos/métodos , Feminino , Humanos , Transplante de Rim/métodos , Masculino , Pessoa de Meia-Idade
8.
Diabet Med ; 33(8): 1094-101, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-26605507

RESUMO

AIMS: To elucidate varicella zoster virus (VZV)-specific cell-mediated immunity and humoral immunogenicity against live attenuated Oka varicella zoster vaccine concurrently vaccinated with 23-valent pneumococcal polysaccharide vaccine (PPSV23) in elderly people with diabetes mellitus. METHODS: This double-blind randomized controlled single-centre study of 60-70-year-old people with diabetes compared immunity and safety profiles 3 months after one dose of varicella zoster vaccine or placebo. PPSV23 was immunized simultaneously. Primary analysis evaluated cell-mediated immunity using the VZV skin test. Secondary analyses were a VZV interferon-γ enzyme-linked immunospot (ELISPOT) assay and immunoadherence haemagglutination test. Adverse experiences were recorded using diary questionnaires. RESULTS: By intent-to-treat analysis, 27 participants with diabetes who had been administered the vaccine were compared with 27 participants who were given a placebo. Changes in skin test scores were 0.41 ± 0.80 and 0.11 ± 0.93 (P = 0.2155), and geometric mean fold rises of the ELISPOT counts were 1.2 [95% confidence interval (CI) 0.2, 7.9] and 1.2 (95% CI 0.2, 7.3) (P = 0.989) in the vaccine and placebo groups, respectively. The geometric mean titre did not increase 3 months after vaccination in either group. No vaccination-related severe adverse experience was reported and no participant developed herpes zoster. DISCUSSION: Our previous results demonstrated that varicella zoster vaccine safely enhanced VZV-specific immunity in elderly people with or without diabetes. The results of this study showed that varicella zoster vaccine can be used safely, but it cannot boost virus-specific immunity in elderly people with diabetes when administered with concurrent PPSV23. Alternative strategies are needed to prevent VZV-associated diseases in this population.


Assuntos
Diabetes Mellitus/imunologia , Vacina contra Herpes Zoster/imunologia , Herpes Zoster/imunologia , Imunidade Celular/imunologia , Imunogenicidade da Vacina/imunologia , Idoso , Método Duplo-Cego , ELISPOT , Feminino , Herpes Zoster/prevenção & controle , Vacina contra Herpes Zoster/uso terapêutico , Herpesvirus Humano 3/imunologia , Humanos , Reação no Local da Injeção/epidemiologia , Reação no Local da Injeção/etiologia , Testes de Liberação de Interferon-gama , Masculino , Pessoa de Meia-Idade , Infecções Pneumocócicas/prevenção & controle , Vacinas Pneumocócicas/uso terapêutico , Prurido/induzido quimicamente , Prurido/epidemiologia , Testes Cutâneos
9.
J Hum Hypertens ; 30(5): 328-34, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26310187

RESUMO

This study was done to clarify the optimal number and type of casual urine specimens required to estimate urinary sodium/potassium (Na/K) ratio in individuals with high blood pressure. A total of 74 individuals with high blood pressure, 43 treated and 31 untreated, were recruited from the Japanese general population. Urinary sodium, potassium and Na/K ratio were measured in both casual urine samples and 7-day 24-h urine samples and then analyzed by correlation and Bland-Altman analyses. Mean Na/K ratio from random casual urine samples on four or more days strongly correlated with the Na/K ratio of 7-day 24-h urine (r=0.80-0.87), which was similar to the correlation between 1 and 2-day 24-h urine and 7-day 24-h urine (r=0.75-0.89). The agreement quality for Na/K ratio of seven random casual urine for estimating the Na/K ratio of 7-day 24-h urine was good (bias: -0.26, limits of agreements: -1.53-1.01), and it was similar to that of 2-day 24-h urine for estimating 7-day 24-h values (bias: 0.07, limits of agreement: -1.03 to 1.18). Stratified analyses comparing individuals using antihypertensive medication and individuals not using antihypertensive medication showed similar results. Correlations of the means of casual urine sodium or potassium concentrations with 7-day 24-h sodium or potassium excretions were relatively weaker than those for Na/K ratio. The mean Na/K ratio of 4-7 random casual urine specimens on different days provides a good substitute for 1-2-day 24-h urinary Na/K ratio for individuals with high blood pressure.


Assuntos
Hipertensão/urina , Potássio/urina , Sódio/urina , Coleta de Urina/normas , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
10.
Rev Sci Instrum ; 86(3): 036102, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25832286

RESUMO

A compact focused gaseous ion beam system has been developed to form proton microbeams of a few hundreds of keV with a penetration depth of micrometer range in 3-dimensional proton beam writing. Proton microbeams with kinetic energies of 100-140 keV were experimentally formed on the same point at a constant ratio of the kinetic energy of the object side to that of the image side. The experimental results indicate that the beam diameters were measured to be almost constant at approximately 6 µm at the same point with the kinetic energy range. These characteristics of the system were experimentally and numerically demonstrated to be maintained as long as the ratio was constant.

11.
J Nutr Health Aging ; 19(4): 375-82, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25809800

RESUMO

BACKGROUND: Rapid increases in life expectancy have led to concurrent increases in the number of elderly people living alone or those forced to change living situations. Previous studies have found that poor dietary intake was common in elderly people living alone. However, there have been few studies about the dietary intake in elderly people living in other situations, particularly those living with family other than a spouse (nonspouse family), which is common in Japan. OBJECTIVE: To examine the differences in dietary intake by different living situations in elderly Japanese people. We analyzed the data of 1542 healthy residents in the town of Ohasama aged 60 years and over who had completed self-administered questionnaires. METHODS: The dietary intake was measured using a validated 141-item food frequency questionnaire. Multiple regression models with robust (White-corrected) standard errors were individually fitted for nutrients and foods by living situation. RESULTS: In men, although the presence of other family was correlated with significantly lower intake of protein-related foods, e.g., legumes, fish and shellfish, and dairy products, these declines were more serious in men living with nonspouse family. Conversely, in men living alone the intake of fruits and vegetables was significantly lower. In women, lower intakes of fruit and protein-related foods were significantly more common in participants living with nonspouse family than those living with only a spouse. CONCLUSION: These findings revealed that elderly people living alone as well as those living with family other than a spouse had poor dietary intake, suggesting that strategies to improve food choices and skills for food preparation could promote of healthy eating in elderly Japanese people.


Assuntos
Povo Asiático , Dieta/estatística & dados numéricos , Características da Família , Saúde , Inquéritos Nutricionais , Estado Nutricional , Idoso , Animais , Laticínios , Comportamento Alimentar , Feminino , Frutas , Avaliação Geriátrica , Humanos , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , Alimentos Marinhos , Autorrelato , Inquéritos e Questionários , Verduras
12.
Eur J Clin Nutr ; 69(4): 482-8, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25585600

RESUMO

BACKGROUND/OBJECTIVES: There have been few studies on the association of fruit and vegetable (FV) intake with cardiovascular disease (CVD) risk in Asian populations where both dietary habits and disease structure are different from western countries. No study in Asia has found its significant association with stroke. We examined associations of FV intake with mortality risk from total CVD, stroke and coronary heart diseases (CHDs) in a representative Japanese sample. METHODS: A total of 9112 participants aged from 24-year follow-up data in the NIPPON DATA80, of which baseline data were obtained in the National Nutrition Survey Japan in 1980, were studied. Dietary data were obtained from 3-day weighing dietary records. Participants were divided into sex-specific quartiles of energy adjusted intake of FV. Multivariate-adjusted hazard ratios (HRs) were calculated between strata of the total of FV intake, fruit intake and vegetable intake. The adjustment included age, sex, smoking, drinking habit and energy adjusted intakes of sodium and some other food groups. RESULTS: Participants with higher FV intake were older, ate more fish, milk and dairy products and soybeans and legumes and ate less meat. Multivariate-adjusted HR (95% confidence interval; P; P for trend) for the highest versus the lowest quartile of the total of FV intake was 0.74 (0.61-0.91; 0.004; 0.003) for total CVD, 0.80 (0.59-1.09; 0.105; 0.036) for stroke and 0.57 (0.37-0.87; 0.010; 0.109) for CHD. CONCLUSIONS: The results showed that higher total intake of FVs was significantly associated with reduced risk of CVD mortality in Japan.


Assuntos
Doenças Cardiovasculares/mortalidade , Frutas , Verduras , Adulto , Idoso , Povo Asiático , Índice de Massa Corporal , Dieta , Registros de Dieta , Inquéritos sobre Dietas , Determinação de Ponto Final , Feminino , Seguimentos , Humanos , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Inquéritos Nutricionais , Modelos de Riscos Proporcionais , Estudos Prospectivos , Fatores de Risco , Acidente Vascular Cerebral/mortalidade
13.
Int J Obes (Lond) ; 39(3): 488-94, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25109783

RESUMO

BACKGROUND/OBJECTIVES: Higher volumes of ectopic cardiovascular fat (ECF) are associated with greater risk of coronary heart disease (CHD). Identifying factors that are associated with ECF volumes may lead to new preventive efforts to reduce risk of CHD. Significant racial/ethnic differences exist for overall and central adiposity measures, which are known to be associated with ECF volumes. Whether racial/ethnic differences also exist for ECF volumes and their associations with these adiposity measures remain unclear. SUBJECTS/METHODS: Body mass index (BMI), computerized tomography-measured ECF volumes (epicardial, pericardial and their summation) and visceral adipose tissue (VAT) were examined in a community-based sample of 1199 middle-aged men (24.2% Caucasians, 7.0% African-Americans, 23.6% Japanese-Americans, 22.0% Japanese, 23.2% Koreans). RESULTS: Significant racial/ethnic differences existed in ECF volumes and their relationships with BMI and VAT. ECF volumes were the highest among Japanese-Americans and the lowest among African-Americans. The associations of BMI and VAT with ECF differed by racial/ethnic groups. Compared with Caucasians, for each 1-unit increase in BMI, African-Americans had lower, whereas Koreans had higher increases in ECF volumes (P-values<0.05 for both). Meanwhile, compared with Caucasians, for each 1-unit increase in log-transformed VAT, African-Americans, Japanese-Americans and Japanese had similar increases, whereas Koreans had a lower increase in ECF volumes (P-value<0.05). CONCLUSIONS: Racial/ethnic groups differed in their propensity to accumulate ECF at increasing level of overall and central adiposity. Future studies should evaluate whether reducing central adiposity or overall weight will decrease ECF volumes more in certain racial/ethnic groups. Evaluating these questions might help in designing race-specific prevention strategy of CHD risk associated with higher ECF.


Assuntos
Adiponectina/sangue , Povo Asiático/estatística & dados numéricos , Asiático/estatística & dados numéricos , Negro ou Afro-Americano/estatística & dados numéricos , Doença das Coronárias/etnologia , Obesidade Abdominal/etnologia , População Branca/estatística & dados numéricos , Índice de Massa Corporal , Doença das Coronárias/epidemiologia , Doença das Coronárias/prevenção & controle , Humanos , Resistência à Insulina , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada Multidetectores , Obesidade Abdominal/patologia , Fatores de Risco , Circunferência da Cintura
14.
Microscopy (Oxf) ; 63 Suppl 1: i6-i7, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25359845

RESUMO

In order to improve properties of functional materials, it is important to understand the relation between the structure and the properties since the structure has large effect to the properties. This can be done by using multi-scale microstructure analysis from macro-scale to nano and atomic scale. Scanning electron microscope (SEM) equipped with focused ion beam (FIB), transmission electron microscope (TEM) and 3D atom probe (3DAP) are complementary analysis tools making it possible to know the structure and the chemistry from micron to atomic resolution. SEM gives us overall microstructural and chemical information by various kinds of detectors such as secondary electron, backscattered electron, EDS and EBSD detectors. Also, it is possible to analyze 3D structure and chemistry via FIB serial sectioning. In addition, using TEM we can focus on desired region to get more complementary information from HRTEM/STEM/Lorentz images, SAED/NBD patterns and EDS/EELS to see the detail micro or nano-structure and chemistry. Especially, combination of probe Cs corrector and split EDS detectors with large detector size enable us to analyze the atomic scale elemental distribution. Furthermore, if the specimen has a complicated 3D nanostructure, or we need to analyze light elements such as hydrogen, lithium or boron, 3DAP can be used as the only technique which can visualize and analyze distribution of all constituent atoms of our materials within a few hundreds nm area. Hence, site-specific sample preparation using FIB/SEM is necessary to get desired information from region of interest. Therefore, this complementary analysis combination works very well to understand the detail of materials.In this presentation, we will show the analysis results obtained from some of functional materials by Carl Zeiss CrossBeam 1540EsB FIB/SEM, FEI Tecnai G(2) F30, Titan G2 80-200 TEMs and locally build laser assisted 3DAP. As the one of the example, result of multi-scale characterization for ultra-fine grain Nd-Fe-B permanent magnet will be shown [1]. In order to improve the magnetic properties, especially to increase the coercivity (resistance against magnetization reversal) of the magnet, decreasing the grain size and isolating each grain by non-ferromagnetic grain boundary phase are quite important since the nucleation of magnetic reversal from grain boundary phase can be suppressed and pinning force of magnetic domain wall at the grain boundary phase can be strengthened. Therefore, micro and nano structure and chemistry analysis can shed a light do grain boundary engineering.Figure 1(a,b) shows SEM BSE images of ultrafine grain Nd-Fe-B sintered magnet and the reconstructed 3D tomography of Nd-rich phases obtained by FIB/SEM serial sectioning. This data can provide us information about the distribution of Nd-rich phase and its volume fraction. Moreover, the HRTEM image from the grain boundary phase, the 3DAP maps and the concentration depth profiles are shown in Fig. 1(c,d,e). This magnet shows high coercivity (1517kA/m), and by comparing these results with the microstructures of low coercivity specimen, importance of grain boundary formation was confirmed and it gives us hint to improve the coercivity further. We will show the detail and results from other materials.jmicro;63/suppl_1/i6/DFU046F1F1DFU046F1Fig. 1.(a) SEM BSE images of ultrafine grain Nd-Fe-B sintered magnet. (b) 3D FIB/SEM tomography of Nd-rich phases. (c) HRTEM image from the grain boundary phase. (d) 3DAP maps of Nd, Cu and Al. (e) Concentration depth profiles for Fe, Nd+Pr, B, Co, Cu and Al, determined from the selected box in (d)[1].

15.
Appl Opt ; 53(12): 2711-9, 2014 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-24787600

RESUMO

We have developed unique solar concentrators for solar-pumped solid-state lasers to improve both efficiency and laser output power. Natural sunlight is collected by a primary concentrator which is a 2 m×2 m Fresnel lens, and confined by a cone-shaped hybrid concentrator. Such solar power is coupled to a laser rod by a cylinder with coolant surrounding it that is called a liquid light-guide lens (LLGL). Performance of the cylindrical LLGL has been characterized analytically and experimentally. Since a 14 mm diameter LLGL generates efficient and uniform pumping along a Nd:YAG rod that is 6 mm in diameter and 100 mm in length, 120 W cw laser output is achieved with beam quality factor M2 of 137 and overall slope efficiency of 4.3%. The collection efficiency is 30.0 W/m2, which is 1.5 times larger than the previous record. The overall conversion efficiency is more than 3.2%, which can be comparable to a commercial lamp-pumped solid-state laser. The concept of the light-guide lens can be applied for concentrator photovoltaics or other solar energy optics.

16.
J Hum Hypertens ; 28(9): 535-42, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24430701

RESUMO

Overweight clusters with high blood pressure (BP), but the independent contribution of both risk factors remains insufficiently documented. In a prospective population study involving 8467 participants (mean age 54.6 years; 47.0% women) randomly recruited from 10 populations, we studied the contribution of body mass index (BMI) to risk over and beyond BP, taking advantage of the superiority of ambulatory over conventional BP. Over 10.6 years (median), 1271 participants (15.0%) died and 1092 (12.9%), 637 (7.5%) and 443 (5.2%) experienced a fatal or nonfatal cardiovascular, cardiac or cerebrovascular event. Adjusted for sex and age, low BMI (<20.7 kg m(-2)) predicted death (hazard ratio (HR) vs average risk, 1.52; P<0.0001) and high BMI (> or = 30.9 kg m(-2)) predicted the cardiovascular end point (HR, 1.27; P=0.006). With adjustments including 24-h systolic BP, these HRs were 1.50 (P<0.001) and 0.98 (P=0.91), respectively. Across quartiles of the BMI distribution, 24-h and nighttime systolic BP predicted every end point (1.13 < or = standardized HR < or = 1.67; 0.046 < or = P<0.0001). The interaction between systolic BP and BMI was nonsignificant (P > or = .22). Excluding smokers removed the contribution of BMI categories to the prediction of mortality. In conclusion, BMI only adds to BP in risk stratification for mortality but not for cardiovascular outcomes. Smoking probably explains the association between increased mortality and low BMI.


Assuntos
Monitorização Ambulatorial da Pressão Arterial , Pressão Sanguínea , Índice de Massa Corporal , Hipertensão/diagnóstico , Hipertensão/etnologia , Obesidade/diagnóstico , Obesidade/etnologia , Adulto , Idoso , Anti-Hipertensivos/uso terapêutico , Ásia/epidemiologia , Pressão Sanguínea/efeitos dos fármacos , Europa (Continente)/epidemiologia , Feminino , Humanos , Hipertensão/tratamento farmacológico , Hipertensão/mortalidade , Hipertensão/fisiopatologia , Incidência , Masculino , Pessoa de Meia-Idade , Obesidade/mortalidade , Obesidade/fisiopatologia , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos , Medição de Risco , Fatores de Risco , Fumar/efeitos adversos , Fumar/mortalidade , América do Sul/epidemiologia , Fatores de Tempo
17.
Ultramicroscopy ; 132: 222-6, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23477852

RESUMO

The Nd-rich phases in pressless processed fine grained Nd-Fe-B sintered magnets have been characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and three dimensional atom probe tomography (3DAP). The combination of the backscattered electron (BSE) and in-lens secondary electron (IL-SE) images in SEM led to an unambiguous identification of four types of Nd-rich phases, NdOx, Ia3 type phase, which is isostructural to Nd2O3, dhcp-Nd and Nd1Fe4B4. In addition, the 3DAP analysis of thin Nd-rich grain boundary layer indicate that the coercivity has a close correlation with the chemistry of the grain boundary phase.

18.
Opt Lett ; 37(13): 2670-2, 2012 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-22743490

RESUMO

We propose a simple and efficient pumping approach for a high-power solar-pumped laser by using a liquid light-guide lens (LLGL) and a hybrid pumping cavity. A 2×2 m Fresnel lens is used as a primary concentrator to collect natural sunlight; 120 W cw laser power and a 4.3% total slope efficiency are achieved with a 6-mm diameter Nd:YAG rod within a 14-mm diameter LLGL. The corresponded collection efficiency is 30.0 W/m(2), which is 1.5 times larger than the previous record. This result is unexpectedly better than that of Cr:Nd:YAG ceramics. It is because the scattering coefficient of Cr:Nd:YAG ceramics is 0.004cm(1), which is 2 times larger than that of the Nd:YAG crystal, although both have similar saturation gains.

19.
Pregnancy Hypertens ; 2(3): 285, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26105405

RESUMO

INTRODUCTION: Nulliparity is believed to be one of the risk factors for hypertension during pregnancy. However, the relationship between parity and out-of-clinic blood pressure during pregnancy is still unknown. OBJECTIVES: The aim of this study was to evaluate clinic blood pressure and blood pressure measured at home during pregnancy among nulliparous and multiparous women. METHODS: This study was a prospective cohort study. We examined blood pressure measured in the clinic and at home among 530 normotensive pregnant women who received antenatal care at a maternity hospital in Japan. Clinic blood pressures were obtained by duplicate measurements at each antenatal care visit. The participants were also required to measure their own blood pressures every morning at home while they were pregnant. A linear mixed model was used for analysis of the blood pressure course throughout pregnancy [1]. The SAS package (version 9.2) was used for the statistical analyses. RESULTS: A total of 315 nulliparous and 215 multiparous women were entered into this study (mean ages 30.1±4.6years and 33.0±4.1years, respectively). Clinic blood pressure during pregnancy among nulliparous women was significantly higher than that among multiparous women (P=0.02/P<0.0001 for systolic/diastolic blood pressure), whereas there were no significant differences in blood pressure measured at home during pregnancy between them (P=0.42/P=0.22 for systolic/diastolic blood pressure). CONCLUSION: Out-of-clinic blood pressure levels during pregnancy have been shown not to differ between nulliparous and multiparous women, while clinic blood pressure during pregnancy among nulliparous women is higher than that among multiparous women.

20.
Neuroscience ; 188: 148-56, 2011 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-21596106

RESUMO

Hydrogen sulfide (H2S), a gasotransmitter, facilitates pain sensation by targeting Ca(v)3.2 T-type calcium channels. The H2S/Ca(v)3.2 pathway appears to play a role in the maintenance of surgically evoked neuropathic pain. Given evidence that chemotherapy-induced neuropathic pain is blocked by ethosuximide, known to block T-type calcium channels, we examined if more selective T-type calcium channel blockers and also inhibitors of cystathionine-γ-lyase (CSE), a major H2S-forming enzyme in the peripheral tissue, are capable of reversing the neuropathic pain evoked by paclitaxel, an anti-cancer drug. It was first demonstrated that T-type calcium channel blockers, NNC 55-0396, known to inhibit Ca(v)3.1, and mibefradil inhibited T-type currents in Ca(v)3.2-transfected HEK293 cells. Repeated systemic administration of paclitaxel caused delayed development of mechanical hyperalgesia, which was reversed by single intraplantar administration of NNC 55-0396 or mibefradil, and by silencing of Ca(v)3.2 by antisense oligodeoxynucleotides. Systemic administration of dl-propargylglycine and ß-cyanoalanine, irreversible and reversible inhibitors of CSE, respectively, also abolished the established neuropathic hyperalgesia. In the paclitaxel-treated rats, upregulation of Ca(v)3.2 and CSE at protein levels was not detected in the dorsal root ganglia (DRG), spinal cord or peripheral tissues including the hindpaws, whereas H(2)S content in hindpaw tissues was significantly elevated. Together, our study demonstrates the effectiveness of NNC 55-0396 in inhibiting Ca(v)3.2, and then suggests that paclitaxel-evoked neuropathic pain might involve the enhanced activity of T-type calcium channels and/or CSE in rats, but not upregulation of Ca(v)3.2 and CSE at protein levels, differing from the previous evidence for the neuropathic pain model induced by spinal nerve cutting in which Ca(v)3.2 was dramatically upregulated in DRG.


Assuntos
Antineoplásicos/toxicidade , Canais de Cálcio Tipo T/metabolismo , Sulfeto de Hidrogênio/metabolismo , Hiperalgesia/metabolismo , Neuralgia/metabolismo , Paclitaxel/toxicidade , Animais , Benzimidazóis/farmacologia , Western Blotting , Ciclopropanos/farmacologia , Inibidores Enzimáticos/farmacologia , Células HEK293 , Humanos , Hiperalgesia/induzido quimicamente , Masculino , Naftalenos/farmacologia , Neuralgia/induzido quimicamente , Técnicas de Patch-Clamp , Ratos , Ratos Wistar
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