Photo-induced relaxation of magnetization in molecular magnet

The experimental study of photo-induced magnetization of hybrid molecular magnet containing cobalt(II) and tungsten(V) magnetic centers bridged by 4,40 -bpy and CN− is presented. The observed increase in magnetization rate is attributed to the defects due to inter-valence transfer between CoIIWV *) CoIIIWIV. The time evolution of magnetization is parameterized by the power law rather than exponential function

Magnetic structure of molecular magnet Fe[Fe(CN)₆]·4H₂O

We have studied the magnetic structure of Fe[Fe(CN)6]·4H2O, prepared by precipitation method, using neutron diffraction technique. Temperature dependent DC magnetization study down to 4.2 K shows that the compound undergoes from a high temperature disordered (paramagnetic) to an ordered magnetic phase transition at 22.6 K. Rietveld analysis of neutron diffraction pattern at 60 K (in its paramagnetic phase) revealed a face centred cubic structure with space group Fm3m. The structure contains three-dimensional network of straight Fe3+-C≡N-Fe3+ chains along the edges of the unit cell cube. Fe3+ ions occupy 4a (0, 0, 0) and 4b (1/2, 1/2, 1/2) positions. Fe3+(0, 0, 0) is surrounded octahedrally by six nitrogen atoms and Fe3+ (1/2, 1/2, 1/2) is surrounded octahedrally by six carbon atoms. Magnetic Rietveld refinement of neutron diffraction data at 11 K shows a ferromagnetic coupling between the two inequivalent Fe3+ sites. Refinement yielded an ordered moment of 4.4(6) and 0.8(6) μB per Fe ion located at (0, 0, 0) and (1/2, 1/2, 1/2), respectively. Ordered moments are found to align along the face diagonal. The observed net moment from low temperature neutron diffraction study is consistent with DC magnetization results

Photoinduced Magnetization in a Thin Fe-CN-Co Film

The magnetization of a thin Fe-Co cyanide film has been investigated from 5 K to 300 K and in fields up to 500 G. Upon illumination with visible light, the magnetization of the film rapidly increases. The original cluster glass behavior is further developed in the photoinduced state and shows substantial changes in critical temperature and freezing temperature.Comment: 2 pages, 2 figures, 1 table, International Conference on Magnetism 200

Association between the Glutathione S-transferase M1 gene deletion and female methamphetamine abusers

Several lines of evidence suggest that increased generation of auto-oxidized dopamine (DA) o-quinone is associated with the neurotoxicity of methamphetamine (MAP) in the brain, and that, as a cellular defenses against DA-derived quinines, glutathione S-transferase (GST) detoxifies auto-oxidized DA o-quinone in the brain. Glutathione S-transferase M1 (GSTM1) of the mu-class of GSTs catalyzes reaction between glutathione and catecholamine o-quinones under physiological conditions. This study was undertaken to investigate the role of the GSTM1 gene deletion polymorphism in the neuropathology of MAP abuse. One hundred fifty-seven MAP abusers and 200 healthy comparison subjects were tested for a genetic polymorphism of GSTM1. The difference in the frequency of deletion (D)/nondeletion (N) alleles between the female abusers and female controls was close to statistical significance (P=0.071), although there was no statistical difference (P=0.651) between male abusers and male controls. Furthermore, the number of female abusers with deletion alleles was significantly (P=0.007, odds ratio: 2.77, 95% CI 1.30-5.89) higher than that of male abusers with deletion alleles. These findings suggest that GSTM1 gene deletion may contribute to a vulnerability to MAP abuse in female subjects, but not in male subjects. (C) 2003 Wiley-Liss, Inc

Terahertz radiation by ultrafast spontaneous polarization modulation in multiferroic BiFeO3_3 thin films

Terahertz (THz) radiation has been observed from multiferroic BiFeO$_3$ thin films via ultrafast modulation of spontaneous polarization upon carrier excitation with illumination of femtosecond laser pulses. The radiated THz pulses from BiFeO$_3$ thin films were clarified to directly reflect the spontaneous polarization state, giving rise to a memory effect in a unique style and enabling THz radiation even at zero-bias electric field. On the basis of our findings, we demonstrate potential approaches to ferroelectric nonvolatile random access memory with nondestructive readability and ferroelectric domain imaging microscopy using THz radiation as a sensitive probe.Comment: 4 pages, 4 figures, submitted to Physical Review Letter

CLINICAL OUTCOMES AFTER BICRUCIATE KNEE LIGAMENT TWO-STAGE RECONSTRUCTION

Introduction: Bicruciate knee ligament injury has not a well-establish surgical protocol in the literature. Objective: To correlate clinical data and intraoperative findings compared to the postoperative evaluation data from Lysholm scale, Tegner activity score and SF-36 questionnaire after bicruciate knee ligament two-stage reconstruction. Materials and Methods: 25 patients (20 males and 05 females) were evaluated, mean age 32.3 years (17 - 53 years), mean BMI 26.2(18.9 -34.9), mean duration of lesion 18.3 months (chronic lesion). The INLAY technique was applied in PCL reconstruction using the central 1/3 of the patellar tendon. After the 3-months minimum interval, ACL reconstruction was arthroscopically performed using hamstrings. An additional surgical procedure was required for 04 patients (patellar tendon -02 cases, MCL-02 cases). Results: With a 24.8-month mean follow-up, in 60% of cases, the posterior drawer test rated zero or + (0.5 cm), while 40% as + + (1cm) and 60% of patients rated good condition/ excellent (Lysholm). Only one patient achieved the pre-lesion Tegner activity level.  The duration of lesion influenced postoperative clinical results negatively, especially regarding parameters such as physical functioning limitation of physical aspects, vitality and mental health (SF-36). Conclusion: the bicruciate knee ligament two-stage reconstruction improved the knee stability and subjective evaluation, but, 96% of patients did not recover the pre-injury status of physical activity. Moreover, the time of injury had an inverse statistical correlation with the subjective evaluation of physical functioning, limitation of physical aspects, vitality and mental health in the S-36 score.Introdução: A lesão ligamentar bicruciada do joelho não possui um protocolo cirúrgico bem estabelecido na literatura. Objetivo: Correlacionar os dados clínicos e os achados intra-operatórios com os dados da avaliação pós-operatória da escala de Lysholm, escore de atividade de Tegner e questionário SF-36 após reconstrução do ligamento bicruzado do joelho em dois estágios. Materiais e Métodos: Foram avaliados 25 pacientes (20 homens e 05 mulheres), idade média 32,3 anos (17 - 53 anos), IMC médio 26,2 (18,9 -34,9), duração média da lesão 18,3 meses (lesão crônica). A técnica INLAY foi aplicada na reconstrução do LCP utilizando o 1/3 central do tendão patelar. Após o intervalo mínimo de 3 meses, a reconstrução do LCA foi realizada artroscopicamente com isquiotibiais. Um procedimento cirúrgico adicional foi necessário para 04 pacientes (tendão patelar -02 casos, casos MCL-02). Resultados: Com seguimento médio de 24,8 meses, em 60% dos casos, o teste da gaveta posterior foi avaliado como zero ou + (0,5 cm), enquanto 40% como + + (1cm) e 60% dos pacientes avaliaram bom estado / excelente (Lysholm). Apenas um paciente atingiu o nível de atividade de Tegner pré-lesão. O tempo de lesão influenciou negativamente os resultados clínicos pós-operatórios, principalmente em relação a parâmetros como limitação do funcionamento físico dos aspectos físicos, vitalidade e saúde mental (SF-36). Conclusão: a reconstrução do ligamento bicruzado do joelho em dois estágios melhorou a estabilidade do joelho e a avaliação subjetiva, mas 96% dos pacientes não recuperaram o estado pré-lesão da atividade física. Além disso, o tempo da lesão apresentou correlação estatística inversa com a avaliação subjetiva da capacidade funcional, limitação dos aspectos físicos, vitalidade e saúde mental no escore S-36

THE EFFECT OF LOWER LIMB TRAINING ON MUSCULAR SUPPORT OF THE KNEE AND RISK OF ANTERIOR CRUCIATE LIGAMENT INJURY.

An intervention study was performed to investigate the effect of lower-limb training programs on knee muscle activation patterns and their potential to support the knee load during running and cutting manoeuvres. It is known that balance training can reduce ACL injury but the underlying mechanisms are unknown. The effects that strength training has on support for the knee joint during sporting manoeuvres are also not known. Analysis of activation levels and patterns of leg muscles during running, sidestepping and crossover-cutting manoeuvres prior to and following 12-week training programs revealed important results in terms of potential support of load on the ACL. Balance training increased co-contraction and supportive muscle activation patterns, as did the combination of machine and balance training to a lesser extent. The strength training programs tended to reduce co-contraction and were associated with changes which would lead to less stability of the knee during sporting manoeuvres. It is recommended that balance training should be implemented to reduce an athlete’s risk of ACL injury