Structural disorder-dependent upconversion in Er3+/Yb3+-doped calcium titanate

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Photoluminescent property of mechanically milled BaWO4 powder

Crystalline BaWO4 (BWO) powder obtained by the polymeric precursor method was structurally disordered by means of high-energy mechanical milling. For the first time a strong and broad photoluminescence (PL) has been measured at room temperature for mechanically milled BWO powder and interpreted by ground-state quantum mechanical calculations in the density functional theory framework. Two periodic models have been studied; one representing the crystalline form and the other one representing the disordered BWO powder. These models allowed the calculation of electronic properties, which are consistent with the experimental results, showing that structural disorder in the lattice is an important condition to generate an intense and broad PL band. (c) 2006 Elsevier B.V. All rights reserved.

Effect of disorder on quantum phase transitions in anisotropic XY spin chains in a transverse field

We present some exact results for the effect of disorder on the critical properties of an anisotropic XY spin chain in a transverse held. The continuum limit of the corresponding fermion model is taken and in various cases results in a Dirac equation with a random mass. Exact analytic techniques can then be used to evaluate the density of states and the localization length. In the presence of disorder the ferromagnetic-paramagnetic or Ising transition of the model is in the same universality class as the random transverse field Ising model solved by Fisher using a real-space renormalization-group decimation technique (RSRGDT). If there is only randomness in the anisotropy of the magnetic exchange then the anisotropy transition (from a ferromagnet in the x direction to a ferromagnet in the y direction) is also in this universality class. However, if there is randomness in the isotropic part of the exchange or in the transverse held then in a nonzero transverse field the anisotropy transition is destroyed by the disorder. We show that in the Griffiths' phase near the Ising transition that the ground-state energy has an essential singularity. The results obtained for the dynamical critical exponent, typical correlation length, and for the temperature dependence of the specific heat near the Ising transition agree with the results of the RSRODT and numerical work. [S0163-1829(99)07125-8].

A double-blind, placebo-controlled treatment trial of citalopram for major depressive disorder in older patients with heart failure: The relevance of the placebo effect and psychological symptoms

Background: Little is known about the treatment of depression in older patients with heart failure. This Study was developed to investigate the effectiveness of antidepressant treatment for major depressive disorder (MDD) in the elderly with heart failure. Methods: We enrolled 72 older outpatients with ejection fraction < 50 and diagnosed with MDD by the structured clinical interview for DSM-IV. Thirty-seven patients, 19 on citalopram and 18 on placebo, initiated an 8-week double-blind treatment phase. Measurements were performed with the 31-item Hamilton Rating Scale for Depression (Ham-D-31), the Montgomery-Asberg rating scale (MADRS) and the Systematic Assessment for Treatment Emergent Effects (SAFTEE). A psychiatrist followed up the patients weekly, performing a consultation for about 20 min to field complaints after the measurements. Results: A trend toward superiority of citalopram over placebo in reducing depression was observed in MADRS scores (15.05 + 9.74 vs 9.44 + 9.25, P = .082) but not on HAM-D scores. The depressive symptomatology significantly decreased in both groups (P < .001). The high rate of placebo response during the double-blind phase (56.3%) led us to conclude the study at the interim analysis with 37 patients. Conclusion: Citalopram treatment of MDD in older patients with heart failure is well-tolerated with low rates of side effects, but was not significantly more effective than placebo in the treatment of depression. Weekly psychiatric follow-up including counseling may contribute to the improvement of depression in this population. Scales weighted on psychological symptoms such as the MADRS are possibly better suited to measure depression severity and improvement in patients with heart failure. (C) 2009 Elsevier Inc. All rights reserved.

Otologic symptoms of temporomandibular disorder and effect of orofacial myofunctional therapy

The aim of this study was to investigate the frequency of otologic symptoms and their relationship to orofacial signs and symptoms of temporomandibular disorder (TMD), and the effect of orofacial myofunctional therapy. The study was conducted on eight asymptomatic subjects (Group C) and 20 subjects with articular TMD, randomly distributed over two groups: one treated using orofacial myofunctional therapy (OMT Group) and a control group with TMD (Group CTMD). Patient selection was based upon the Research Diagnostic Criteria for TMD (RDC/TMD). All subjects submitted to a clinical examination with self-reporting of symptom severity, and to orofacial myofunctional and electromyographic evaluation at diagnosis and again, at the end of the study. Correlations were calculated using the Pearson test and inter- and intragroup comparisons were made (p<0.05). In the diagnosis phase, subjects with TMD reported earache (65%), tinnitus (60%), ear fullness (90%), and 25% of the asymptomatic subjects reported tinnitus. The otologic symptoms were correlated with tenderness to palpation of the temporomandibular muscles and joints and with orofacial symptoms. Only the OMT group showed a reduction of otologic and orofacial symptoms, of tenderness to palpation and of the asymmetric index between muscles. OMT may help with muscle coordination and a remission of TMD symptoms.

Depressive disorder moderates the effect of the FTO gene on body mass index.

There is evidence that obesity-related disorders are increased among people with depression. Variation in the FTO (fat mass and obesity associated) gene has been shown to contribute to common forms of human obesity. This study aimed to investigate the genetic influence of polymorphisms in FTO in relation to body mass index (BMI) in two independent samples of major depressive disorder (MDD) cases and controls. We analysed 88 polymorphisms in the FTO gene in a clinically ascertained sample of 2442 MDD cases and 809 controls (Radiant Study). In all, 8 of the top 10 single-nucleotide polymorphisms (SNPs) showing the strongest associations with BMI were followed-up in a population-based cohort (PsyCoLaus Study) consisting of 1292 depression cases and 1690 controls. Linear regression analyses of the FTO variants and BMI yielded 10 SNPs significantly associated with increased BMI in the depressive group but not the control group in the Radiant sample. The same pattern was found in the PsyCoLaus sample. We found a significant interaction between genotype and affected status in relation to BMI for seven SNPs in Radiant (P<0.0057), with PsyCoLaus giving supportive evidence for five SNPs (P-values between 0.03 and 0.06), which increased in significance when the data were combined in a meta-analysis. This is the first study investigating FTO and BMI within the context of MDD, and the results indicate that having a history of depression moderates the effect of FTO on BMI. This finding suggests that FTO is involved in the mechanism underlying the association between mood disorders and obesity.

Effect of orlistat in obese patients with binge eating disorder.

OBJECTIVE: Binge eating disorder represents a significant public health problem, with up to 50% of weight loss program participants displaying this disorder. In previous studies with orlistat, patients with binge eating disorder were excluded. The goal of this study was to assess the efficacy of orlistat in obese patients with binge eating disorder. RESEARCH METHODS AND PROCEDURES: Eighty-nine patients with clinically diagnosed binge eating disorder and a BMI > or = 30 kg/m2 were randomized in double-blind fashion to 24 weeks of treatment with 120 mg of orlistat or placebo three times daily, in combination with a mildly reduced-calorie diet. RESULTS: After 24 weeks, the mean weight loss from baseline for orlistat-treated patients was significantly greater than for patients receiving placebo (-7.4% vs. -2.3%; p = 0.0001) (intent-to-treat analysis). The overall Eating Disorder Inventory 2 score at week 24 was significantly lower in patients treated with orlistat than in those in the placebo group (p = 0.011). DISCUSSION: Orlistat may be considered as part of the management for patients with obesity and binge eating disorder.

Class effect of pharmacotherapy in bipolar disorder: fact or misbelieff?

BACKGROUND: Anecdotal reports suggests that most clinicians treat medications as belonging to a class with regard to all therapeutic indications; this means that the whole 'class' of drugs is considered to possesses a specific therapeutic action. The present article explores the possible existence of a true 'class effect' for agents available for the treatment of bipolar disorder. METHODS: We reviewed the available treatment data from randomized controlled trials (RCTs) and explored 16 'agent class'/'treatment issue' cases for bipolar disorder. Four classes of agents were examined: first-generation antipsychotics (FGAs), second-generation antipsychotics (SGAs), antiepileptics and antidepressants, with respect to their efficacy on four treatment issues of bipolar disorder (BD) (acute mania, acute bipolar depression, maintenance against mania, maintenance against depression). RESULTS: From the 16 'agent class'/' treatment issue' cases, only 3 possible class effects were detected, and they all concerned acute mania and antipsychotics. Four effect cases have not been adequately studied (FGAs against acute bipolar depression and in maintenance protection from depression, and antidepressants against acute mania and protection from mania) and they all concern treatment cases with a high risk of switching to the opposite pole, thus research in these areas is poor. There is no 'class effect' at all concerning antiepileptics. CONCLUSIONS: The available data suggest that a 'class effect' is the exception rather than the rule in the treatment of BD. However, the possible presence of a 'class effect' concept discourages clinicians from continued scientific training and reading. Focused educational intervention might be necessary to change this attitude.

Effect of auditory training on the middle latency response in children with (central) auditory processing disorder

The purpose of this study was to determine the middle latency response (MLR) characteristics (latency and amplitude) in children with (central) auditory processing disorder [(C)APD], categorized as such by their performance on the central auditory test battery, and the effects of these characteristics after auditory training. Thirty children with (C)APD, 8 to 14 years of age, were tested using the MLR-evoked potential. This group was then enrolled in an 8-week auditory training program and then retested at the completion of the program. A control group of 22 children without (C)APD, composed of relatives and acquaintances of those involved in the research, underwent the same testing at equal time intervals, but were not enrolled in the auditory training program. Before auditory training, MLR results for the (C)APD group exhibited lower C3-A1 and C3-A2 wave amplitudes in comparison to the control group [C3-A1, 0.84 µV (mean), 0.39 (SD - standard deviation) for the (C)APD group and 1.18 µV (mean), 0.65 (SD) for the control group; C3-A2, 0.69 µV (mean), 0.31 (SD) for the (C)APD group and 1.00 µV (mean), 0.46 (SD) for the control group]. After training, the MLR C3-A1 [1.59 µV (mean), 0.82 (SD)] and C3-A2 [1.24 µV (mean), 0.73 (SD)] wave amplitudes of the (C)APD group significantly increased, so that there was no longer a significant difference in MLR amplitude between (C)APD and control groups. These findings suggest progress in the use of electrophysiological measurements for the diagnosis and treatment of (C)APD.

Effect of the order and disorder of BaMoO4 powders in photoluminescent properties

The study of the photoluminescent properties affected by order and disorder of the BaMoO4 powders is the principal objective in this work. BaMoO4 compounds were prepared using soft chemical process called Complex Polymerization Method. In this work, different deagglomeration types and different heating rates were used to promote different disorder degrees. Scheelite type phase (BaMoO4) was determined by X-ray Diffraction (XRD), Fourier Transformed Infra-Red (FTIR) and Raman spectroscopy after heat treating the sample at 400 degrees C. The room temperature luminescence spectra revealed an intense single-emission band in the visible region. Based on XRD and Raman data it was observed that the transition between the completely disordered structure to completely ordered structure is a good condition for photoluminescence (PL) emission. The best PL emission is obtained when the material possesses short range disorder, i.e., is periodically ordered (XRD), but some disorder as measured by Raman spectroscopy. The excellent optical properties observed for disordered BaMoO4 suggested that this material is a highly promising candidate for optical applications.

On the effect of aromatherapy with citrus fragrance in the therapy of major depressive disorder

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

The effect of overweight/obesity on cognitive function in euthymic individuals with bipolar disorder

Background. - Persistent impairment in cognitive function has been described in euthymic individuals with bipolar disorder. Collective work indicates that obesity is associated with reduced cognitive function in otherwise healthy individuals. This sub-group post-hoc analysis preliminarily explores and examines the association between overweight/obesity and cognitive function in euthymic individuals with bipolar disorder. Methods. - Euthymic adults with DSM-IV-TR-defined bipolar I or II disorder were enrolled. Subjects included in this post-hoc analysis (n = 67) were divided into two groups (normal weight, body mass index [BMI] of 18.5-24.9 kg/m(2); overweight/obese, BMI >= 25.0 kg/m(2)). Demographic and clinical information were obtained at screening. At baseline, study participants completed a comprehensive cognitive battery to assess premorbid IQ, verbal learning and memory, attention and psychomotor processing speed, executive function, general intellectual abilities, recollection and habit memory, as well as self-perceptions of cognitive failures. Results. - BMI was negatively correlated with attention and psychomotor processing speed as measured by the Digit Symbol Substitution Test (P < 0.01). Overweight and obese bipolar individuals had a significantly lower score on the Verbal Fluency Test when compared to normal weight subjects (P < 0.05). For all other measures of cognitive function, non-significant trends suggesting a negative association with BMI were observed, with the exception of measures of executive function (i.e. Trail Making Test B) and recollection memory (i.e. process-dissociation task). Conclusion. - Notwithstanding the post-hoc methodology and relatively small sample size, the results of this study suggest a possible negative effect of overweight/obesity on cognitive function in euthymic individuals with bipolar disorder. Taken together, these data provide the impetus for more rigorous evaluation of the mediational role of overweight/obesity (and other medical co-morbidity) on cognitive function in psychiatric populations. (C) 2011 Elsevier Masson SAS. All rights reserved.

Influence of defects and disorder on anomalous Hall effect and spin Seebeck effect on permalloy and Heusler compounds

In dieser Arbeit wurden dünne Schichten von Heusler-Verbindungen hergestellt und auf ihre Transporteigenschaften hin untersucht.rnDer Anomale Hall-Effekt (AHE) ist dabei von besonderem Interesse. Er ist ein seit langer Zeit bekannter, jedoch noch nicht vollständig verstandener Transport-Effekt. Die meisten Veröffentlichungen theoretischer Arbeiten konzentrieren sich auf den Einfluss eines bestimmten Beitrags zum AHE. Tatsächlich gemessene experimentelle Daten können jedoch oft nicht in Einklang mit idealisierten Annahmen gebracht werden. rnDie vorliegende Arbeit diskutiert die Ergebnisse, welche aus Messungen von Materialien mit niedrigem Restwiderstand erhalten wurden. rnrnAls prototypische Materialien wurden hier hyphenation Heusler-Verbindungen untersucht. Als Material mit einer komplexen Topologie der Fermi-Fläche zeichnet sich dort der Einfluss von Defekten und der Unordnung der Kristallstruktur deutlich ab.rnrnDurch Verwendung von Filmen mit unterschiedlichem Grad der Unordnung können verschiedene Streumechanismen unterschieden werden. Für Co$_{2}$FeSi$_{0.6}$Al$_{0.4}$ and Co$_{2}$FeGa$_{0.5}$Ge$_{0.5}$ zeigt sich ein positiver AHE bei einer Unordnung vom Typ B2 und bei einer induzierten temperaturabh"angigen Streuung, wo hingegen eine Typ DO$_{3}$-Unordnung zusammen mit anderen möglichen intrinsischen Beiträgen einen negativen Effekt hervorruft.rnrnDarüber hinaus wurden die magneto-optische Kerr-Effekte (MOKE) dieser Verbindungen untersucht. Hierfür wurden Beiträge erster Ordnung als Funktion der intrinsischen und extrinsischen Parameter qualitativ analysiert. Auf den Einfluss der kristallinen Ordnung auf Beiträge zweiter Ordnung des MOKE-Signals wird ebenfalls eingegangen.rnrnDes Weiteren wurden dünne Schichten der Heusler-Verbindung Co$_{2}$MnAl auf MgO- und Si-Subs-traten (beide (100)) mit Hochfrequenz-Mag-netron-Sputtern erzeugt. Die zusammensetzung sowie die magnetischen und Transport-Eigenschaften wurden hinsichtlich unterschiedlicher Abscheidebedingungen systematisch untersucht.rnrnInsbesondere zeigt der AHE-Widerstand ein außerordentliches temperaturunabhängiges Verhalten in einem Bereich moderater Magnetfeldstärken von 0 bis 0.6,T. Hierf"ur wurde der nicht-diagonale Transport bei Temperaturen bis zu 300,$^{circ}$C analysiert. Die Daten zeigen die Eignung des Materials für Hall-Sensoren auch oberhalb der Raumtemperatur.rnrnJüngst wurde der Spin Seebeck-Effekt (SSE) entdeckt. Der Effekt aus dem Bereich der Spin-Kaloritronik erzeugt eine Spin-Spannung'' aufgrund eines Temperaturgradienten in magnetischen Materialien. Hier werden vorläufige Messungen des SSE in Ni$_{80}$Fe$_{20}$ und in Heusler-Verbindungen präsentiert.rn

A combined analysis of two randomized controlled trials evaluating the effect of Mindfulness-Based Stress Reduction on self-reported emotional experience and physiological symptoms among Veterans with Posttraumatic Stress Disorder

Thesis (Master's)--University of Washington, 2016-06