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Weyl fermions as emergent quasiparticles can arise in Weyl semimetals (WSMs) in which the energy bands are nondegenerate, resulting from inversion or time-reversal symmetry breaking. Nevertheless, experimental evidence for magnetically induced WSMs is scarce. Here, using photoemission spectroscopy, we observe that the degeneracy of Bloch bands is already lifted in the paramagnetic phase of EuCd2As2. We attribute this effect to the itinerant electrons experiencing quasi-static and quasi-long-range ferromagnetic fluctuations. Moreover, the spin-nondegenerate band structure harbors a pair of ideal Weyl nodes near the Fermi level. Hence, we show that long-range magnetic order and the spontaneous breaking of time-reversal symmetry are not essential requirements for WSM states in centrosymmetric systems and that WSM states can emerge in a wider range of condensed matter systems than previously thought.
RESUMEN
OBJECTIVES: To establish a method for rapid identification of bloodstain age. METHODS: Under laboratory conditions ï¼20 â, 25 â and 30 âï¼, an integrating sphere ISR-240A was used as a reflection accessory on an UV-2450 UV-vis spectrophotometer, and a standard white board of BaSO4 was used as reference, the reflection spectrums of bloodstain from human ears' venous blood were measured at regular intervals. The reflection radios R541 and R577 at a specific wavelength were collected and the value of R541/R577 was calculated. The linear fitting and regression analysis were done by SPSS 17.0. RESULTS: The results of regression analysis showed that R² of the ratios of bloodstain age to UV visible reflectivity in specific wavelengths were larger than 0.8 within 8 hours and under certain circumstances. The regression equation was established. The bloodstain age had significant correlation with the value of R541/R577. CONCLUSIONS: The method of inspection is simple, rapid and nondestructive with a good reliability, and can be used to identify the bloodstain age within 8 hours elapsed-time standards under laboratory conditions.
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Manchas de Sangre , Análisis Espectral/métodos , Rayos Ultravioleta , Ciencias Forenses , Humanos , Estándares de Referencia , Reproducibilidad de los Resultados , Factores de TiempoRESUMEN
OBJECTIVE: Epidural scar adhesion is one of the major causes of the failed back surgery syndrome after laminectomy. Recent studies have shown that simvastatin has potent anti-fibrotic and anti-inflammatory properties. This study evaluates the effect of the topical application of simvastatin on reducing epidural scar adhesion after laminectomy in rats. MATERIALS AND METHODS: Thirty-six male Sprague-Dawley rats were randomly divided into three groups: control, chitosan and simvastatin group. After laminectomy was performed at L1 level, simvastatin and chitosan were applied to the laminectomy sites. The control group received no additional treatment. Four weeks later, the rats were killed and the epidural adhesion was evaluated by macroscopic assessment, hydroxyproline content analysis and histological analysis. The number of fibroblasts and the optical density of the collagen were also determined. RESULTS: The results showed that simvastatin could reduce epidural scar adhesion in rats. Little epidural adhesions were seen in the laminectomy sites treated with simvastatin. The hydroxyproline content, the number of fibroblasts and the optical density of the collagen in the simvastatin group were significantly less than those of the chitosan and control group. However, dense epidural adhesion was found in control group. CONCLUSIONS: Topical application of simvastatin could reduce epidural scar adhesion after laminectomy in rats. Further research is necessary to determine the optimal dosage and the safety of simvastatin.
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Cicatriz/prevención & control , Laminectomía/métodos , Simvastatina/administración & dosificación , Administración Tópica , Animales , Cicatriz/etiología , Cicatriz/metabolismo , Cicatriz/patología , Colágeno/metabolismo , Espacio Epidural , Fibroblastos/efectos de los fármacos , Fibroblastos/patología , Laminectomía/efectos adversos , Masculino , Distribución Aleatoria , Ratas , Ratas Sprague-Dawley , Adherencias Tisulares/etiología , Adherencias Tisulares/metabolismo , Adherencias Tisulares/patología , Adherencias Tisulares/prevención & controlRESUMEN
BACKGROUND: Meta-analyses support the efficacy of cognitive-behavioural therapy (CBT) for schizophrenia in western cultures. This study aimed to compare the efficacy of CBT and supportive therapy (ST) for patients with schizophrenia in China. METHOD: A multicentre randomized controlled, single-blinded, parallel-group trial enrolled a sample of 192 patients with schizophrenia. All patients were offered 15 sessions of either CBT or ST over 24 weeks and followed up for an additional 60 weeks. All measures used were standardized instruments with good reliability and validity. The Positive and Negative Syndrome Scale (PANSS) was used to assess symptoms of schizophrenia. The Schedule for Assessing Insight (SAI) was used to assess patients' insight and the Personal and Social Performance Scale (PSP) was used to assess their social functioning. RESULTS: Effect-size analysis showed that patients made rapid improvements in all symptoms, insight and social functioning as measured by the PANSS, SAI and PSP at 12 and 24 weeks and maintained these improvements over the course of the study to 84 weeks. Patients in the CBT group showed significantly greater and more durable improvement in PANSS total score (p = 0.045, between-group d = 0.48), positive symptoms (p = 0.018, between-group d = 0.42) and social functioning (p = 0.037, between-group d = 0.64), with significant differences emerging after completion of therapy. CONCLUSIONS: Both CBT and ST combined with medication had benefits on psychopathology, insight and social functioning of patients with schizophrenia. CBT was significantly more effective than ST on overall, positive symptoms and social functioning of patients with schizophrenia in the long term.
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Antipsicóticos/uso terapéutico , Terapia Cognitivo-Conductual/métodos , Esquizofrenia/terapia , Ajuste Social , Adulto , Beijing , Terapia Combinada , Femenino , Humanos , Masculino , Método Simple Ciego , Resultado del Tratamiento , Adulto JovenRESUMEN
AIM: Serum cystatin C has been proposed as a better marker of glomerular filtration rate than serum creatinine. SYNTAX score (SXscore) can accurately reflect the severity of coronary artery disease (CAD). However, the association between Cystatin C-based glomerular filtration rate (eGFRcys) and SXscore in patients with diabetes has never been reported. METHODS: We prospectively included 656 consecutive patients with diabetes who were angiographically diagnosed with CAD from January 2010 to December 2011. Renal function was assessed by eGFRcys. SXscore was calculated using SXscore algorithm. Ordinal logistic regression and Pearson correlation were used to analyze the association between eGFRcys and SXscore. RESULTS: Patients with renal dysfunction were older, more often female, more likely to have a history of hypertension and less tobacco use when compared with those patients with normal renal function. Age, sex, SBP, DBP, fasting glucose, HbA1c, TC, LDL, HDL, TG, BMI and CRP were not different among SXscore tertile groups. Incidence of hypertension, hyperlipidemia, family history and tobacco use were similar among these groups. Correlation analysis suggested that eGFRcys was negatively correlated with SXscore (R=-0.255, P<0.001). Ordinal logistic regression showed that eGFRcys was an independent predictor of SXscore (ß=-0.027, P<0.001). CONCLUSIONS: eGFRcys was an independent predictor of SXscore in patients with diabetes. This might help explain the increased risk of CVD events and mortality in patients with renal dysfunction. Further prospectively multiple centre studies are required to better quantify this finding.
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Angiografía Coronaria , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Cistatina C/sangre , Diabetes Mellitus/sangre , Diabetes Mellitus/diagnóstico por imagen , Tasa de Filtración Glomerular/fisiología , Anciano , Angiografía Coronaria/métodos , Enfermedad de la Arteria Coronaria/etiología , Diabetes Mellitus/fisiopatología , Angiopatías Diabéticas/sangre , Angiopatías Diabéticas/diagnóstico por imagen , Angiopatías Diabéticas/fisiopatología , Nefropatías Diabéticas/sangre , Nefropatías Diabéticas/diagnóstico por imagen , Nefropatías Diabéticas/fisiopatología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Insuficiencia Renal Crónica/sangre , Insuficiencia Renal Crónica/diagnóstico por imagen , Insuficiencia Renal Crónica/fisiopatología , Proyectos de Investigación , Índice de Severidad de la EnfermedadRESUMEN
Although the magnetoelectric effects - the mutual control of electric polarization by magnetic fields and magnetism by electric fields, have been intensively studied in a large number of inorganic compounds and heterostructures, they have been rarely observed in organic materials. Here we demonstrate magnetoelectric coupling in a metal-organic framework [(CH3)2NH2]Mn(HCOO)3 which exhibits an order-disorder type of ferroelectricity below 185 K. The magnetic susceptibility starts to deviate from the Curie-Weiss law at the paraelectric-ferroelectric transition temperature, suggesting an enhancement of short-range magnetic correlation in the ferroelectric state. Electron spin resonance study further confirms that the magnetic state indeed changes following the ferroelectric phase transition. Inversely, the ferroelectric polarization can be improved by applying high magnetic fields. We interpret the magnetoelectric coupling in the paramagnetic state in the metal-organic framework as a consequence of the magnetoelastic effect that modifies both the superexchange interaction and the hydrogen bonding.
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The underlying neurobiological factors involved in sexual orientation are largely unknown. This study investigated whether neural circuits or different cognitive processes accounted for differences in brain activation in 14 heterosexual and 14 homosexual males. Brain scans were undertaken in each subject using functional magnetic resonance imaging while they viewed different sexual stimuli, i.e. heterosexual couple stimuli (HCS), gay couple stimuli (GCS), lesbian couple stimuli (LCS) and neutral stimuli (NS). Ratings of sexual attractiveness of the stimuli were assessed. Subjective sexual arousal was induced by HCS and GCS in heterosexual and homosexual men, respectively. Sexual disgust was induced by GCS and LCS in heterosexual and homosexual men, respectively. Compared with viewing NS, viewing sexual stimuli induced significantly different brain activations, most of which had the characteristics of cognitive processes. These observations suggest that different cognitive patterns may be the major cause of different subjective responses to sexual stimuli between heterosexual and homosexual men.
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Encéfalo/fisiología , Cognición/fisiología , Hemodinámica/fisiología , Heterosexualidad , Homosexualidad , Oxígeno/sangre , Conducta Sexual , Adolescente , Adulto , Estudios de Casos y Controles , Emociones , Femenino , Heterosexualidad/fisiología , Heterosexualidad/psicología , Homosexualidad/fisiología , Homosexualidad/psicología , Homosexualidad Femenina , Humanos , Imagen por Resonancia Magnética , Masculino , Estimulación Luminosa/métodos , Conducta Sexual/fisiología , Conducta Sexual/psicología , Adulto JovenRESUMEN
BACKGROUND AND PURPOSE: Nowadays the mechanism of homosexuality is little known. Few studies have been carried out to explore the brain functional changes of homosexual men during sexual arousal. We used functional MR imaging (fMRI) to determine whether the patterns of brain activation in homosexual and heterosexual men differed during visually evoked sexual arousal. MATERIALS AND METHODS: To all the subjects (10 homosexual and 10 heterosexual), real-time visual stimulation was provided by 3-minute exposure to 3 types of erotic film: heterosexual couples (F-M), male homosexual couples (M-M), and female homosexual couples (F-F) engaged in sexual activity, during which time fMRI was used to determine the patterns of brain activation. Self-reports of level of sexual arousal were collected immediately afterward. RESULTS: Statistical parametric mapping showed that viewing erotic film excerpts that induced sexual arousal was associated, in both groups, with activation of the middle prefrontal gyrus, bilateral temporal lobe and postcentral gyrus, thalamus, insula, vermis, left precuneus, occipital cortex, parietal cortex, and cerebellum. In homosexual men, the left angular gyrus, left caudate nucleus, and right pallidum were activated; in contrast, heterosexual men showed no activation in these regions. However, heterosexual men showed activation in the bilateral lingual gyrus, right hippocampus, and right parahippocampal gyrus, areas not activated in homosexual men. In both groups, region-of-interest analysis revealed no correlation between the magnitude of amygdala or thalamus activation and the reported level of sexual arousal. CONCLUSION: Our findings indicate that different neural circuits are active during sexual arousal in homosexual and heterosexual men and may contribute to a better understanding of the neural basis of male sexual orientation.