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1.
Phys Rev Lett ; 128(24): 247202, 2022 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-35776447

RESUMEN

Experimental measurements show that the angular dependence of the anisotropic magnetoresistance (AMR) in L1_{0} ordered FePt epitaxial films on the current orientation and magnetization direction is a superposition of the corresponding dependences of twofold and fourfold symmetries. The twofold AMR exhibits a strong dependence on the current orientation, whereas the fourfold term only depends on the magnetization direction in the crystal and is independent of the current orientation. First-principles calculations reveal that the fourfold AMR arises from the relaxation time anisotropy due to the variation of the density of states near the Fermi energy under rotation of the magnetization. This relaxation time anisotropy is a universal property in ferromagnetic metals and determines other anisotropic physical properties that are observable in experiment.

2.
Nat Commun ; 12(1): 5266, 2021 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-34489461

RESUMEN

The time-resolved magneto-optical (MO) Voigt effect can be utilized to study the Néel order dynamics in antiferromagnetic (AFM) materials, but it has been limited for collinear AFM spin configuration. Here, we have demonstrated that in Mn3Sn with an inverse triangular spin structure, the quench of AFM order by ultrafast laser pulses can result in a large Voigt effect modulation. The modulated Voigt angle is significantly larger than the polarization rotation due to the crystal-structure related linear dichroism effect and the modulated MO Kerr angle arising from the ferroic ordering of cluster magnetic octupole. The AFM order quench time shows negligible change with increasing temperature approaching the Néel temperature (TN), in markedly contrast with the pronounced slowing-down demagnetization typically observed in conventional magnetic materials. This atypical behavior can be explained by the influence of weakened Dzyaloshinskii-Moriya interaction rather than the smaller exchange splitting on the diminished AFM order near TN. The temperature-insensitive ultrafast spin manipulation can pave the way for high-speed spintronic devices either working at a wide range of temperature or demanding spin switching near TN.

3.
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi ; 33(6): 647-649, 2021 Dec 15.
Artículo en Chino | MEDLINE | ID: mdl-35128900

RESUMEN

An imported case of acute schistosomiasis was reported in Wuhan City in 2020. The case was infected with Schistosoma by contact with the infested water due to playing water in the Yangtze River when working out of Hubei Province. The patient visited four medical institutions and the duration from onset to definitive diagnosis was 20 days. The patient's low awareness of schistosomiasis prevention and control knowledge and lack of diagnosis and treatment awareness for schistosomiasis among medical institutions were considered as main causes of the development of acute schistosomiasis and progression to severe case. Intensifying schistosomiasis health education among mobile populations and improving the awareness and capability of early diagnosis of schistosomiasis among clinicians are recommended.


Asunto(s)
Esquistosomiasis , Animales , China/epidemiología , Ciudades , Humanos , Ríos , Schistosoma , Esquistosomiasis/diagnóstico , Esquistosomiasis/epidemiología , Esquistosomiasis/prevención & control , Caracoles , Agua
4.
Zhonghua Yi Xue Za Zhi ; 100(25): 1937-1941, 2020 Jul 07.
Artículo en Chino | MEDLINE | ID: mdl-32629592

RESUMEN

Objective: To study the clinical features, continuous care and prognosis of the patients with severe and refractory anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis after intensive care unit (ICU). Methods: Clinical data of patients with severe and refractory anti-NMDAR encephalitis, who were transferred from ICU to general ward of neurology between December 2015 and October 2019, were retrospectively reviewed and analyzed in the study. Results: Twenty patients (11 females and 9 males) were enrolled in the study. The median course of disease when patients were transferred to general ward was 4.4 (2.0, 6.0) months. Six cases were alert, 6 cases were in a coma, 5 were in the early recovery phase and 3 were in the late recovery phase. Severe malnutrition, pneumonia, urinary tract infections, bedsores and leukocytopenia were common complications. Seven out of 18 patients were tested positive for cerebrospinal fluid anti-NMDAR antibodies with high titers (≥1∶100). During this continuous therapy stage,10 patients were treated with intravenous immunoglobulin (IVIg), 1 with methylprednisolone, 2 with rituximab, 1 with intrathecal methotrexate and 1 received intravenous cyclophosphamide. All Patients were prescribed a long-term immunotherapy (mycophenolate mofetil 1.5-3.0 g/d). Sixteen patients (80%) had good prognosis (modified Rankin Scale (mRS)≤2), and the mortality was 10%, with follow-up time of 17.0 (8.0, 27.0) months. Conclusions: Patients with anti-NMDAR encephalitis, who are transferred from ICU, have severely impaired neurologic function. These patients need long-term individualized immunotherapy and continuous neurological care. Good outcomes can be achieved in most patients.


Asunto(s)
Encefalitis Antirreceptor N-Metil-D-Aspartato , Cuidados Críticos , Femenino , Humanos , Masculino , Pronóstico , Receptores de N-Metil-D-Aspartato , Estudios Retrospectivos
5.
Zhonghua Yi Xue Za Zhi ; 98(14): 1093-1098, 2018 Apr 10.
Artículo en Chino | MEDLINE | ID: mdl-29690722

RESUMEN

Objective: To prospectively investigate the changes in nutritional status of patients with malignant tumors during hospitalization by using nutritional risk screening (NRS2002), and to analyze the correlation between the nutritional status and clinical outcomes . Methods: This was a prospective and parallel research done by multi-center collaboration from 34 hospitals in China from June to September 2014.Hospitalized patients with malignant tumors inthese departments (Department of Gastroenterology, respiratory medicine, oncology, general surgery, thoracic surgery and geriatrics)were investigated. Only the patients with age≥ 18 years and hospitalization time between 7-30 days were included. During hospitalization, the physical indexes of human bodywere measured, and the NRS 2002 scores, and monitored the nutritional support at the time points of admission and 24 hours before discharge were recorded.And whether there was a nutritional risk in hospitalized patients and its association with clinical outcomes were investigated. Results: A total of 2 402 patients with malignancies were enrolled in this study. Seventy fourpatients who did not complete NRS2002 were eliminated, and 2 328 patients were included. The number of the main diseases was the top five, including 587 cases of colorectal cancer, 567 cases of lung cancer, 564 cases of gastric cancer, 146 cases of esophageal cancer, and 119 cases of liver tumor. At the time of discharge, compared with admission, the BMI, body weight, grip and calf circumferences of patients with malignant tumor were significantly decreased (P<0.05). The total protein, albumin, prealbumin and hemoglobin were significantly lower than those at admission (P<0.05). In 2 328 patients who were completed nutritional risk screening, the rate of malnutrition at admission was 11.1% (BMI =18.5, 258/2 328) and the rate of malnutrition at discharge was 10.9% (BMI =18.5, 254/2 328), there were no significant differences (χ(2)=0.019 7, P=0.888). There were 1 204 patients with nutritional risk at admission (51.7%, NRS2002 score≥3)and 1 352 patients with nutritional risk at discharge (58.1%, NRS2002 score≥3), with significant differences (χ(2)=49.9, P<0.001). The incidence of nutritional risk in patients with colorectal, stomach, and lung tumors at discharge was significantly higher than that at admission (P<0.05). The infective complications and other complications of patients with nutritional risk were significantly greater than those without nutritional risk at admission and at discharge.ICU hospitalization stay of patients with nutritional risk was increased significantly than those without nutritional risk at admission(P=0.042). Hospitalization expenses of patients with nutritional risk was increased significantly than those of patients without nutritional risk at discharge(P<0.01). Conclusion: The patients with malignant tumor have a higher incidence rate of malnutrition at both admission and discharge and malnutritionhas correlation with adverse clinical outcomes.The aboveindicators did not improve significantly at discharge.Doctors should pay more attention to the nutritional status (screening and evaluation)of patients before discharge and use appropriate and adequate nutrition support in order to prevent the weight loss and improve the life quality of patients.


Asunto(s)
Hospitalización , Neoplasias/complicaciones , Evaluación Nutricional , Estado Nutricional , Adulto , Anciano , China , Femenino , Hemoglobinas , Humanos , Tiempo de Internación , Masculino , Desnutrición , Persona de Mediana Edad , Apoyo Nutricional , Alta del Paciente , Estudios Prospectivos , Calidad de Vida , Factores de Riesgo , Pérdida de Peso
6.
Plant Biol (Stuttg) ; 20(2): 327-337, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29125673

RESUMEN

Sorbitol dehydrogenase (SDH) catalyses the reversible oxidation of sorbitol, xylitol and ribitol to their corresponding ketoses. In this study, we investigated the expression and role of Arabidopsis SDH in salt and osmotic stress tolerance, and abscisic acid (ABA) response. The expression patterns of SDH were investigated using transgenic Arabidopsis plants expressing beta-glucuronidase (GUS) under control of the promoter with the first intron of SDH. qRT-PCR and histochemical assay of GUS activity were used to study SDH expression regulation by ABA, salt and osmotic stress. SDH-overexpression lines of Arabidopsis were used to investigate the role of SDH in salt and osmotic stress, and ABA response. Arabidopsis SDH was predominantly expressed in source organs such as green cotyledons, fully expanded leaves and sepals, especially in vascular tissues of theses organs. SDH expression was inhibited by NaCl and mannitol treatments. Seed germination and post-germination growth of SDH-overexpressing lines exhibited decreased sensitivity to salt and osmotic stress compared to WT plants. The transcript of SDH was induced by ABA. Overexpression of SDH decreased sensitivity to ABA during seed germination and post-germination growth. Expression of AAO3 increased but ABI5 and MYB2 decreased in SDH-overexpressing lines after ABA treatment. This study demonstrates that expression of SDH is regulated by ABA, salt and osmotic stress. SDH functions in plant tolerance to salt and osmotic stress, and ABA response via specific regulating gene expression of ABA synthesis and signalling in Arabidopsis.


Asunto(s)
Ácido Abscísico/metabolismo , Arabidopsis/metabolismo , L-Iditol 2-Deshidrogenasa/metabolismo , Presión Osmótica/fisiología , Reguladores del Crecimiento de las Plantas/metabolismo , Tolerancia a la Sal/fisiología , Arabidopsis/fisiología , Cotiledón/metabolismo , Flores/metabolismo , Regulación de la Expresión Génica de las Plantas/fisiología , Glucuronidasa/metabolismo , L-Iditol 2-Deshidrogenasa/fisiología , Hojas de la Planta/metabolismo , Plantas Modificadas Genéticamente , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
7.
Sci Rep ; 5: 13640, 2015 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-26348277

RESUMEN

We report on the experimental and theoretical studies of cooling field (HFC) and temperature (T) dependent exchange bias (EB) in FexAu1-x/Fe19Ni81 spin glass (SG)/ferromagnet (FM) bilayers. When x varies from 8% to 14% in the FexAu1-x SG alloys, with increasing T, a sign-changeable exchange bias field (HE) together with a unimodal distribution of coercivity (HC) are observed. Significantly, increasing in the magnitude of HFC reduces (increases) the value of HE in the negative (positive) region, resulting in the entire HE∼T curve to move leftwards and upwards. In the meanwhile, HFC variation has weak effects on HC. By Monte Carlo simulation using a SG/FM vector model, we are able to reproduce such HE dependences on T and HFC for the SG/FM system. Thus this work reveals that the SG/FM bilayer system containing intimately coupled interface, instead of a single SG layer, is responsible for the novel EB properties.

8.
Sci Rep ; 5: 9183, 2015 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-25777540

RESUMEN

In this work, disordered-IrMn3/insulating-Y3Fe5O12 exchange-biased bilayers are studied. The behavior of the net magnetic moment ΔmAFM in the antiferromagnet is directly probed by anomalous and planar Hall effects, and anisotropic magnetoresistance. The ΔmAFM is proved to come from the interfacial uncompensated magnetic moment. We demonstrate that the exchange bias and rotational hysteresis loss are induced by partial rotation and irreversible switching of the ΔmAFM. In the athermal training effect, the state of the ΔmAFM cannot be recovered after one cycle of hysteresis loop. This work highlights the fundamental role of the ΔmAFM in the exchange bias and facilitates the manipulation of antiferromagnetic spintronic devices.

9.
J Fish Dis ; 37(2): 113-21, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25254273

RESUMEN

An enzootic disease characterized by granulomas in internal organs occurred in cage-farmed large yellow croaker, Larimichthys crocea (Richardson), in April and November 2010, in Ningbo, Zhejiang Province. One bacterial strain, named XSDHY-P, was isolated from the diseased fish and identified by biochemical characterization, fatty acid methyl ester (FAME) analysis and multilocus sequence analysis (MLSA). According to the results obtained from the biochemical tests, FAME analysis and phylogenetic analysis derived from 16S ribosomal RNA, gyrB, oprF, oprI, oprL and rpoD gene sequencing, the bacterial isolate, XSDHY-P, was identified as Pseudomonas plecoglossicida. Moreover, lethal dose, 50% trials were carried out to demonstrate the virulence of XSDHY-P in large yellow croaker when administered at 2.13 9 105 colony-forming units per fish. Visceral granulomas were found in the experimentally infected fish as well as in the naturally infected fish, indicating that P. plecoglossicida is another bacterial pathogen that causes granulomatosis in L. crocea.


Asunto(s)
Enfermedades de los Peces/microbiología , Granuloma/veterinaria , Perciformes/fisiología , Pseudomonas/fisiología , Animales , Enfermedades de los Peces/mortalidad , Granuloma/microbiología , Granuloma/mortalidad , Tipificación de Secuencias Multilocus , Filogenia , Pseudomonas/clasificación , Pseudomonas/genética , Pseudomonas/ultraestructura , ARN Ribosómico 16S/genética
10.
Eur J Neurol ; 21(7): 1032-9, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24698428

RESUMEN

BACKGROUND AND PURPOSE: Metabolic syndrome (MetS) has been reported to be associated with silent lacunar infarction, which is highly related to white matter lesions (WMLs). However, little is known about the relationship between MetS and the prevalence of WMLs. The association between MetS, its components and WMLs in middle-aged and elderly patients was investigated. METHODS: Consecutive patients aged 50 years and older were prospectively enrolled in this study. All participants underwent magnetic resonance imaging scans to assess the presence and severity of WMLs. The MetS was defined according to the updated National Cholesterol Education Program's Adult Treatment Panel III criteria. Multivariate logistic regression analyses were performed to examine the relationship between MetS, its components and WMLs. RESULTS: A total of 852 patients were enrolled in the study. MetS was present in 38.4%. MetS was associated with an increased risk of periventricular WMLs (PVWMLs) and deep WMLs (DWMLs) after multivariable adjustment (odds ratio 3.21, 95% confidence interval 2.26-4.55 for PVWMLs; odds ratio 2.93, 95% confidence interval 2.09-4.09 for DWMLs). Amongst MetS components, elevated blood pressure, elevated fasting blood glucose and low high density lipoprotein cholesterol were associated with PVWMLs, whilst elevated blood pressure and low high density lipoprotein cholesterol were related to DWMLs. CONCLUSIONS: Our findings demonstrate that MetS is associated with the prevalence of PVWMLs and DWMLs independent of other risk factors in middle-aged and elderly patients. The association between MetS as a cluster and WMLs was not driven by MetS components.


Asunto(s)
Leucoencefalopatías/epidemiología , Leucomalacia Periventricular/epidemiología , Síndrome Metabólico/epidemiología , Anciano , Comorbilidad , Femenino , Humanos , Leucoencefalopatías/patología , Leucomalacia Periventricular/patología , Imagen por Resonancia Magnética , Masculino , Síndrome Metabólico/patología , Persona de Mediana Edad
11.
Scand J Surg ; 102(4): 234-40, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24056141

RESUMEN

BACKGROUND: The objective of this study was to compare the effectiveness and cosmetic results of tissue adhesive or surgical staples in thyroidectomy through a supraclavicular incision. METHODS: This was a prospective, randomized study of consecutive patients undergoing thyroidectomy by a supraclavicular approach. Eligible patients were randomized into two groups: one group had the incision closed with tissue adhesive (the experimental group) and the other with surgical staples (the control group). The main outcomes included operative time, early postoperative pain measured by Visual Analog Scale, incidence of wound dehiscence and infection, perceived cosmetic outcome, and overall patient satisfaction by using Patient Satisfaction Assessment Form. RESULTS: There were 151 consecutive patients assessed for eligibility, and 132 patients were enrolled over 22 months. The clinical characteristics of the patients in the two groups were similar. Main outcomes were assessed in the first 24 h postoperatively, the first month, and the third month postoperatively. Operation time was longer in the experimental group (P = 0.027). Mean Visual Analog Scale scores for pain were lower in the experimental group in the early postoperative period (P < 0.001). No patients developed surgical site infections or wound dehiscence. Lower scores for scar assessment and higher overall satisfaction levels at the first month after surgery were found in the experimental group compared to the control group (P < 0.001). There was no significant difference between the two groups at the third month postoperatively in perceived cosmetic result (P = 0.052) or overall satisfaction (P = 0.059). CONCLUSIONS: Tissue adhesive is effective and reliable in skin closure for thyroid surgery. While this closure may take somewhat longer to perform, it leads to less postoperative pain, more acceptable wound cosmesis, and higher patient satisfaction levels in short postoperative follow-up.


Asunto(s)
Suturas , Tiroidectomía , Adhesivos Tisulares , Técnicas de Cierre de Heridas/instrumentación , Adulto , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Tempo Operativo , Dimensión del Dolor , Dolor Postoperatorio/epidemiología , Dolor Postoperatorio/prevención & control , Satisfacción del Paciente/estadística & datos numéricos , Estudios Prospectivos , Grapado Quirúrgico , Dehiscencia de la Herida Operatoria/epidemiología , Dehiscencia de la Herida Operatoria/prevención & control , Infección de la Herida Quirúrgica/epidemiología , Infección de la Herida Quirúrgica/prevención & control , Resultado del Tratamiento
12.
Phys Rev Lett ; 110(7): 077203, 2013 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-25166400

RESUMEN

The dependence of the intrinsic Gilbert damping parameter α(0) on the spin-orbital coupling strength ξ is investigated in L1(0) ordered FePd(1-x) Pt(x) films by time-resolved magneto-optical Kerr effect measurements and spin-dependent ab initio calculations. Continuous tuning of α(0) over more than one order of magnitude is realized by changing the Pt/Pd concentration ratio showing that α(0) is proportional to ξ(2) as changes of other leading parameters are found to be negligible. The perpendicular magnetic anisotropy is shown to have a similar variation trend with x. The present results may facilitate the design and fabrication of new magnetic alloys with large perpendicular magnetic anisotropy and tailored damping properties.

13.
Vet J ; 196(1): 111-3, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23103218

RESUMEN

Serum resistance in Haemophilus parasuis strain SC096 has been shown to be dependent on expression of the outer membrane protein P2 (OmpP2) and loss of the ompP2 gene results in significantly greater sensitivity to both porcine and rabbit sera. However, the mechanism of complement activation by the serum sensitive ΔompP2 strain is unknown. In this study, the classical complement pathway is demonstrated to be the main pathway for killing the H. parasuis ΔompP2 strain, and not the mannan-binding lectin (MBL) or alternative pathway. In addition, absorption of antibodies against ΔompP2 strain or depletion of IgGs from serum inhibited serum killing activity, which could be restored by addition of heat-inactivated serum or purified IgGs. Western blot analysis indicated that the OmpP2 mutant could bind significantly more IgGs than the wild type strain SC096 when incubated with serum. Finally, IgGs in normal rabbit serum targeted to the OMPs, but not lipooligosaccharide (LOS) in the OmpP2 mutant strain were found to be involved in bacterial killing indicating that the bactericidal epitope(s) is in the outer membrane proteins.


Asunto(s)
Vía Clásica del Complemento , Haemophilus parasuis/inmunología , Lectina de Unión a Manosa/inmunología , Animales , Anticuerpos Antibacterianos/sangre , Proteínas de la Membrana Bacteriana Externa/metabolismo , Western Blotting/veterinaria , Electroforesis en Gel de Poliacrilamida/veterinaria , Haemophilus parasuis/genética , Inmunoglobulina G/metabolismo , Lipopolisacáridos/metabolismo , Conejos
14.
Phys Rev Lett ; 109(6): 066402, 2012 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-23006287

RESUMEN

The anomalous Hall effect (AHE) in L1(0)FePd(1-x)Pt(x) alloy films is studied both experimentally and theoretically. We find that the intrinsic contribution (σ(AH)(int)) to the AHE can be significantly increased, whereas the extrinsic side-jump contribution (σ(AH)(sj)) can be continuously reduced from being slightly larger than σ(AH)(int) in L1(0) FePd to being much smaller than σ(AH)(int) in L1(0) FePt, by increasing the Pt composition x. We show that this chemical composition tuning of the intrinsic contribution is afforded by the stronger spin-orbit coupling strength on the Pd/Pt site when the lighter Pd atoms are replaced by the heavier Pt atoms. Our results provide a means of manipulating the competing AHE mechanisms in ferromagnetic alloys for fully understanding the AHE and also for technological applications of ferromagnetic alloys.

15.
J Fish Dis ; 34(4): 265-71, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21294750

RESUMEN

The 16S-23S intergenic spacers (ITS) of ribosomal DNA from ten independent isolates of Streptococcus iniae and one reference strain ATCC29178 were sequenced, aligned and used to design a polymerase chain reaction (PCR) primer set for rapid and specific detection and identification of S. iniae. This primer set amplified a 377-bp DNA fragment specifically from S. iniae, but not from other common bacterial pathogens of fish or from non-fish pathogens. The PCR conditions were optimized to allow detection of the organism from agar, broth culture or infected fish tissue. The sensitivity of the PCR assay was established by the detection of DNA as low as 0.02 ng or as few as 10 CFU bacterial cells. The establishment of the specific PCR assay provides a useful tool for the identification and diagnosis of fish infection with S. iniae.


Asunto(s)
ADN Bacteriano/aislamiento & purificación , ADN Espaciador Ribosómico/genética , Enfermedades de los Peces/microbiología , Reacción en Cadena de la Polimerasa/métodos , Streptococcus/aislamiento & purificación , Tilapia/microbiología , Animales , Secuencia de Bases , Cartilla de ADN/genética , ADN Bacteriano/genética , ADN Espaciador Ribosómico/aislamiento & purificación , Marcadores Genéticos , Datos de Secuencia Molecular , ARN Ribosómico/genética , ARN Ribosómico/aislamiento & purificación , Alineación de Secuencia , Streptococcus/clasificación , Streptococcus/genética
16.
Opt Lett ; 35(7): 971-3, 2010 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-20364187

RESUMEN

Femtosecond-laser drilling may induce holes in HgCdTe with morphology similar to that induced by ion-milling in loophole technique. So-formed hole structures are proven to be pn junction diodes by the laser beam induced current characterization as well as the conductivity measurement. Transmission and photoluminescence spectral measurements on a n-type dominated hole-array structure give rise to different results from those of an ion-milled sample.

17.
J Phys Condens Matter ; 21(4): 046002, 2009 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-21715829

RESUMEN

Electron spin resonance (ESR) spectra of polycrystalline La(0.75)(Ca(x)Sr(1-x))(0.25)MnO(3) (x = 0, 0.45, 1) were studied within the temperature range 110 K≤T≤470 K. The temperature dependence of the ESR intensity for the samples is described by a thermally activated model in the paramagnetic regime. It is found that the activation energy in the orthorhombic phase is higher than that in the rhombohedral phase for La(0.75)(Ca(0.45)Sr(0.55))(0.25)MnO(3). It is suggested that a higher energy is required to destroy the correlated polarons due to the fact that correlated polarons only exist in the orthorhombic phase. This proposition is confirmed by the analysis of the ESR linewidth data, which can be well fitted by the model of adiabatic hopping motion of small polarons. In addition, it is found that, at a fixed temperature, the linewidth decreases with increasing Sr doping, which reveals that the structural tolerance factor has a significant effect on the linewidth.

18.
Transplant Proc ; 40(10): 3384-9, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19100395

RESUMEN

BACKGROUND: Rejection in renal transplantation is the most frequent event causing transplant failure. It is important to identify parameters to predict rejection, which are helpful in a timely fashion. METHODS: Fifty-nine renal transplant recipients were divided into two groups: group 1 (stable renal function) and group 2 (acute rejection episodes). The levels of HLA-A mRNA in peripheral blood lymphocytes (both pre- and posttransplantation) were measured by reverse transcriptase-polymerase chain reaction (RT-PCR) with glucose-6-phosphate dehydrogenase (G6PDH) as an internal reference. The TEST software was used to analyze the relative expressions of HLA-A mRNA. RESULTS: There was no statistical significance between features of the two groups pretransplant versus normal controls. Posttransplant, the HLA-A mRNA levels decreased significantly compared to those of pretransplant and normal control individuals. The levels of HLA-A mRNA among the 10 patients with acute rejection episodes were significantly increased. There was no significant change in the lymphocyte populations in the early stage of an acute rejection episode compared with the prerejection value. CONCLUSION: HLA-A mRNA expression was strongly correlated with immune status. The HLA-A mRNA levels may provide an effective and reliable indicator to predict acute rejection episodes in renal transplantation.


Asunto(s)
Rechazo de Injerto/epidemiología , Antígenos HLA-A/genética , Trasplante de Riñón/efectos adversos , Linfocitos/inmunología , ARN Mensajero/genética , Adolescente , Adulto , Biopsia , Femenino , Glucosafosfato Deshidrogenasa/genética , Rechazo de Injerto/genética , Rechazo de Injerto/patología , Humanos , Trasplante de Riñón/patología , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Adulto Joven
19.
Phys Rev Lett ; 101(14): 147207, 2008 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-18851570

RESUMEN

For polycrystalline NiFe/FeMn bilayers, we have observed and quantified the rotation of the pinning direction in the exchange bias training and recovery effects. During consecutive hysteresis loops, the rotation of the pinning direction strongly depends on the magnetization reversal mechanism of the ferromagnet layer. The interfacial uncompensated magnetic moment of antiferromagnetic grains may be irreversibly switched and rotated when the magnetization reversal process of the ferromagnet layer is accompanied by domain wall motion and domain rotation, respectively.

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