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Enhanced Activity of Titanocene Complex for Electrocatalytic Nitrogen Reduction Reaction
Enhanced titanocene (Cp2TiCl2) based electrocatalytic system for nitrogen reduction was shown, comprising glassy carbon electrode, high level of the catechol redox mediator, optimized binary THF/MeOH solvent and unique design of the reactor having ammonia permeable membrane at the outlet, which allowed constant nitrogen flow through the working solution during entire electrolysis without risk of evaporation of the solvent. Catalytic activity was observed in the potential range of (â1.5)â(â2.3) V, reaching TON of 2.83%, corresponding to the production of 0.566 ÎŒmol NH3 (9.64 ÎŒg) in 24 h hydrolysis at â2.3 V using 0.02 mmol TiCp2Cl2 (5 mg).</jats:p
Towards hydrogen-rich ionic (NH4)(BH3NH2BH2NH2BH3) and related molecular NH3BH2NH2BH2NH2BH3
Attempts of synthesis of ionic (NH4)(BH3NH2BH2NH2BH3) using metathetical
approach resulted in a mixture of the target compound and a partly
dehydrogenated molecular NH3BH2NH2BH2NH2BH3 product. The mixed specimen was
characterized by NMR and vibrational spectroscopies, and the crystal structure
of their cocrystal was solved from powder x-ray diffraction data, and
supplemented by theoretical density functional theory calculations. Despite
their impressive hydrogen content, and similarly to ammonia borane, both title
compounds release hydrogen substantially polluted with borazine, and traces of
ammonia and diborane.Comment: 8 pages, 10 Figures, 2 Tables, and electronic supplement of 19 page
A novel clinical score (InterTAK Diagnostic Score) to differentiate takotsubo syndrome from acute coronary syndrome: results from the International Takotsubo Registry
AIMS. Clinical presentation of takotsubo syndrome (TTS) mimics acute coronary syndrome (ACS) and does not allow differentiation. We aimed to develop a clinical score to estimate the probability of TTS and to distinguish TTS from ACS in the acute stage.
METHODS AND RESULTS: Patients with TTS were recruited from the International Takotsubo Registry ( www.takotsubo-registry.com) and ACS patients from the leading hospital in Zurich. A multiple logistic regression for the presence of TTS was performed in a derivation cohort (TTS, n = 218; ACS, n = 436). The best model was selected and formed a score (InterTAK Diagnostic Score) with seven variables, and each was assigned a score value: female sex 25, emotional trigger 24, physical trigger 13, absence of ST-segment depression (except in lead aVR) 12, psychiatric disorders 11, neurologic disorders 9, and QTc prolongation 6 points. The area under the curve (AUC) for the resulting score was 0.971 [95% confidence interval (CI) 0.96-0.98] and using a cut-off value of 40 score points, sensitivity was 89% and specificity 91%. When patients with a score of â„50 were diagnosed as TTS, nearly 95% of TTS patients were correctly diagnosed. When patients with a score â€31 were diagnosed as ACS, âŒ95% of ACS patients were diagnosed correctly. The score was subsequently validated in an independent validation cohort (TTS, n = 173; ACS, n = 226), resulting in a score AUC of 0.901 (95% CI 0.87-0.93).
CONCLUSION: The InterTAK Diagnostic Score estimates the probability of the presence of TTS and is able to distinguish TTS from ACS with a high sensitivity and specificity
Happy heart syndrome. role of positive emotional stress in takotsubo syndrome
AIMS: Takotsubo syndrome (TTS) is typically provoked by negative stressors such as grief, anger, or fear leading to the popular term 'broken heart syndrome'. However, the role of positive emotions triggering TTS remains unclear. The aim of the present study was to analyse the prevalence and characteristics of patients with TTS following pleasant events, which are distinct from the stressful or undesirable episodes commonly triggering TTS.
METHODS AND RESULTS: Takotsubo syndrome patients with preceding pleasant events were compared to those with negative emotional triggers from the International Takotsubo Registry. Of 1750 TTS patients, we identified a total of 485 with a definite emotional trigger. Of these, 4.1% (n = 20) presented with pleasant preceding events and 95.9% (n = 465) with unequivocal negative emotional events associated with TTS. Interestingly, clinical presentation of patients with 'happy heart syndrome' was similar to those with the 'broken heart syndrome' including symptoms such as chest pain [89.5% (17/19) vs. 90.2% (412/457), P = 1.0]. Similarly, electrocardiographic parameters, laboratory findings, and 1-year outcome did not differ. However, in a post hoc analysis, a disproportionate higher prevalence of midventricular involvement was noted in 'happy hearts' compared with 'broken hearts' (35.0 vs. 16.3%, P = 0.030).
CONCLUSION: Our data illustrate that TTS can be triggered by not only negative but also positive life events. While patient characteristics were similar between groups, the midventricular TTS type was more prevalent among the 'happy hearts' than among the 'broken hearts'. Presumably, despite their distinct nature, happy and sad life events may share similar final common emotional pathways, which can ultimately trigger TTS
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