Sol–gel synthesis and characterization of Co-doped LSGM perovskites

One of the major requirements for the development and commercialization of low-cost SOFCs is the reduction in the operating temperature. One of the methods to reach this aim is the use of solid electrolytes which exhibit superior ionic conductivity at intermediate temperatures (IT, T < 800 °C). Among these ionic conductors, doped LaGaO3 materials show high oxide ionic conductivity in the 600–800 °C range. These perovskites are usually prepared by time- and energy-consuming solid state reaction. In this paper, La0.8Sr0.2Ga0.8Mg0.2O2.8 (LSGM) and La0.8Sr0.20Ga0.8Mg0.2−xCoxO3−δ (LSGMC) powders containing different amounts of Co (x = 0.05, 0.085 and 0.10) were prepared from precursors synthesised by citrate sol–gel method. The precursors were calcined at 1000 °C (10 h) and dense high-purity pellets were obtained by pressing (300 MPa) and sintering in air at 1475 °C (5, 10 and 20 h). Sintered pellets of LSGM and LSGMC contained very small amounts (<1%) of SrLaGa3O7 and SrLaGaO4, respectively, as detected by X-ray diffraction (XRD) and by the combined use of scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). The data clearly showed the feasibility of sol–gel methods to produce Co-doped LSGM perovskite type oxides

Sol–gel synthesis, X-ray photoelectron spectroscopy and electrical conductivity of Co-doped (La, Sr)(Ga, Mg)O3−δ perovskites

La0.8Sr0.2Ga0.8Mg0.2−xCoxO3−δ (LSGMC) powders containing different amounts of Co (x = 0.05 and 0.085) were prepared by a citrate sol–gel method. The powders were used to prepare highly phase-pure LSGMC sintered pellets with controlled composition and fractional densities larger than 95%. For the first time, LSGMC materials were subjected to X-ray photoelectron spectroscopy (XPS) characterization. XPS data confirmed the presence of the dopants in the material and allowed to identify two different chemical states for Sr2+ and oxygen, both related to the oxygen-deficient perovskite structure of LSGMC. The conductivity of LSGMC sintered pellets containing different amounts of Co ions in the B sites of the perovskite lattice was assessed by electrochemical impedance spectroscopy (EIS) in the 250–750 °C temperature range. Conductivity values and apparent activation energies were in good agreement with previously published data referring to materials with same composition, but prepared by solid-state route. Therefore, the physicochemical and electrochemical characterization clearly demonstrated the ability of sol–gel methods to produce high-purity Co-doped LSGM perovskites, which represent promising solid electrolytes for intermediate-temperature SOFCs

Idiopathic isolated clitoromegaly: A report of two cases

BACKGROUND: Clitoromegaly is a frequent congenital malformation, but acquired clitoral enlargement is relatively rare. METHODS: Two acquired clitoromegaly cases treated in Atatürk Training Hospital, Izmir, Turkey are presented. RESULTS: History from both patients revealed clitoromegaly over the last three years. Neither gynecological nor systemic abnormalities were detected in either patient. Karyotype analyses and hormonal tests were normal. Abdominal and gynaecological ultrasound did not show any cystic lesion or other abnormal finding. Computerized tomography scan of the adrenal glands was normal. Clitoroplasty with preservation of neurovascular pedicles was performed for the treatment of clitoromegaly. CONCLUSION: The patients were diagnosed as "idiopathic isolated" clitoromegaly. To the best of our knowledge, there has been no detailed report about idiopathic clitoromegaly in the literature

Predictors of Peritraumatic Reactions and PTSD Following the September 11th Terrorist Attacks

In this study the authors characterize peritraumatic reactions of residents of New York City during and immediately following the September 11th terrorist attacks, identify predictors of those reactions, and identify predictors of PTSD 4 months later. A cross–sectional sample of New York residents (n = 2,001) responded to questions about sociodemographics, historical factors, event–related exposure; acute cognitive, emotional, and physiological reactions to the September 11th terrorist attacks; and current (past month) PTSD symptoms. Factor analyses of peritraumatic reactions yielded three related, but distinct, peritraumatic response patterns—dissociation, emotional reactions, and panic/physiological arousal. Several demographic, historical, and exposure–related variables predicted one or more peritraumatic reaction patterns. After controlling for demographic, historical, and exposure factors, each of the peritraumatic reactions factors, one historical factor and one event–related exposure factor remained as significant predictors of PTSD. These results support a growing literature concerning the predictive value of peritraumatic reactions in relation to PTSD. Implications for preventive efforts and suggestions for future research are discussed.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/40315/2/Lawyer_Predictors of peritraumatic reactions and PTSD_2006.pd

CHA2DS2-VASc score predicts atrial fibrillation recurrence after cardioversion: systematic review and individual patient pooled meta-analysis

BackgroundDespite progresses in the treatment of the thromboembolic risk related to atrial fibrillation (AF), the management of recurrences remains a challenge.HypothesisTo assess if congestive heart failure or left ventricular systolic dysfunction (CHA2DS2‐VASc) score is predictive of early arrhythmia recurrence after AF cardioversion.MethodsSystematic review and individual patient pooled meta‐analysis following Preferred Reporting Items for Systematic reviews and Meta‐Analyses guidelines. Inclusion criteria: observational trials in patients with AF undergoing cardioversion, available data on recurrence of AF and available data on CHA2DS2‐VASc score. Clinical studies of interest were retrieved by PubMed, Cochrane Library, and Biomed Central. Seven authors were contacted for joining the patient level meta‐analysis, and three shared data regarding anthropometric measurements, risk factors, major comorbidities, and CHA2DS2‐VASc score. The primary outcome was the recurrence of AF after cardioversion in patients free from antiarrhythmic prophylaxis. Univariate and multivariate logistic regression was performed.ResultsOverall, we collect data of 2889 patients: 61% were male, 50% with hypertension, 12% with diabetes, and 23% with history of ischemic heart disease. The median CHA2DS2‐VASc score was 2.. At the multivariate analysis, chronic kidney disease (odds ratio [OR] 1.94; 95% confidence interval [CI] 1.12‐3.27; P = 0.01), peripheral artery disease (OR 1.65; 95% CI 1.23‐2.19; P P  2 (OR 1.37; 95% CI 1.1‐1.68; P = 0.002) were independent predictors of early recurrence of AF.ConclusionsCHA2DS2‐VASc score predicts early recurrence of AF in the first 30 days after electrical or pharmacological cardioversion.N

Television Watching and Mental Health in the General Population of New York City After September 11

The September 11, 2001 terrorist attacks were watched on television by millions. Using data from a telephone survey of New York City residents in January 2002 (N = 2001), we examined the relations between television watching and probable posttraumatic stress disorder (PTSD) after the attacks. Among those who were directly affected by the attacks or had prior traumatic experiences, watching television was associated with probable PTSD. Experiencing a peri-event panic reaction accounted for some of the association between television watching and probable PTSD. Future research directions are suggested for better understanding the mechanisms behind observed associations between television watching and PTSD.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/40284/2/Ahern_Television Watching and Mental Health in_2005.pd