Temporal Evolution of Defects and Related Electric Properties in He-Irradiated YBa2Cu3O7-δ Thin Films.

Thin films of the superconductor YBa2Cu3O7-δ (YBCO) were modified by low-energy light-ion irradiation employing collimated or focused He+ beams, and the long-term stability of irradiation-induced defects was investigated. For films irradiated with collimated beams, the resistance was measured in situ during and after irradiation and analyzed using a phenomenological model. The formation and stability of irradiation-induced defects are highly influenced by temperature. Thermal annealing experiments conducted in an Ar atmosphere at various temperatures demonstrated a decrease in resistivity and allowed us to determine diffusion coefficients and the activation energy ΔE=(0.31±0.03) eV for diffusive oxygen rearrangement within the YBCO unit cell basal plane. Additionally, thin YBCO films, nanostructured by focused He+-beam irradiation into vortex pinning arrays, displayed significant commensurability effects in magnetic fields. Despite the strong modulation of defect densities in these pinning arrays, oxygen diffusion during room-temperature annealing over almost six years did not compromise the signatures of vortex matching, which remained precisely at their magnetic fields predicted by the pattern geometry. Moreover, the critical current increased substantially within the entire magnetic field range after long-term storage in dry air. These findings underscore the potential of ion irradiation in tailoring the superconducting properties of thin YBCO films.

Ordered Bose Glass of Vortices in Superconducting YBa2Cu3O7-δ Thin Films with a Periodic Pin Lattice Created by Focused Helium Ion Irradiation.

The defect-rich morphology of YBa2Cu3O7-δ (YBCO) thin films leads to a glass-like arrangement of Abrikosov vortices which causes the resistance to disappear in vanishing current densities. This vortex glass consists of entangled vortex lines and is identified by a characteristic scaling of the voltage-current isotherms. Randomly distributed columnar defects stratify the vortex lines and lead to a Bose glass. Here, we report on the observation of an ordered Bose glass in a YBCO thin film with a hexagonal array of columnar defects with 30 nm spacings. The periodic pinning landscape was engineered by a focused beam of 30 keV He+ ions in a helium-ion microscope.

Anisotropy of the In-Plane and Out-of-Plane Resistivity and the Hall Effect in the Normal State of Vicinal-Grown YBa2Cu3O7-δ Thin Films.

The resistivity and the Hall effect in the copper-oxide high-temperature superconductor YBa2Cu3O7-δ (YBCO) are remarkably anisotropic. Using a thin film of YBCO grown on an off-axis cut SrTiO3 substrate allows one to investigate these anisotropic transport properties in a planar and well-defined sample geometry employing a homogeneous current density. In the normal state, the Hall voltage probed parallel to the copper-oxide layers is positive and strongly temperature dependent, whereas the out-of-plane Hall voltage is negative and almost temperature independent. The results confirm previous measurements on single crystals by an entirely different measurement method and demonstrate that vicinal thin films might be also useful for investigations of other layered nanomaterials.

Evaluation of the Manchester triage system for patients with acute coronary syndrome.

BACKGROUND: An early diagnosis of acute coronary syndrome (ACS) is crucial for treatment and prognosis. The aim of this study was to evaluate the Manchester triage system (MTS) for patients with ACS, e.g. ST-segment elevation myocardial infarction (STEMI), non-ST elevation myocardial infarction (N-STEMI) and unstable angina pectoris (UAP). METHODS: Retrospective analysis of patients diagnosed with ACS (STEMI, N­STEMI and UAP) who were triaged in the emergency department (ED) with the MTS. RESULTS: In this study 282 patients with ACS (STEMI: 34.0%, N­STEMI: 61.7%, UAP: 4.3%) were triaged as MTS level 1 (immediate assessment): 0.4%, MTS level 2 (very urgent): 51.4%, MTS level 3 (urgent): 41.5%, MTS level 4 (standard): 6.7%, MTS level 5 (non-urgent): 0%. We observed significantly lower mean MTS levels in males (male: 2.48 ± 0.59, female: 2.68 ± 0.68, p = 0.02) and in patients younger than 80 years (age <80 years: 2.50 ± 0.61, age ≥80 years: 2.70 ± 0.67, p = 0.03). We did not find a significant difference of mean MTS levels in different types of ACS (STEMI: 2.46 ± 0.6, N­STEMI: 2.59 ± 0.64, STEMI vs N­STEMI: p = 0.11, UAP: 2.67 ± 0.65, STEMI vs UAP: p = 0.26) and with respect to diabetes (diabetic: 2.47 ± 0.57, non-diabetic: 2.58 ± 0.65, p = 0.13). The in-hospital mortality was 2.5% (MTS level 2: n = 3, MTS level 3: n = 3, MTS level 4: n = 1). CONCLUSION: The majority of patients with ACS were classified as MTS levels 2 and 3. There was no significant difference of mean MTS levels in patients with STEMI, NSTEMI and UAP. In order to assure an early diagnosis of STEMI, an electrocardiogram (ECG) should be carried out immediately or at least within 10 min after first medical contact in the ED in all patients suspected for ACS, irrespective of the assigned MTS level.

Does early administration of selenium improve neurological outcome after cardiac arrest?

OBJECTIVE: Existing data indicate that selenium supplementation may be beneficial in critically ill patients and in those with ischemic stroke. The purpose of this retrospective study was to explore the influence of early administration of selenium on neurological outcome after cardiopulmonary resuscitation (CPR). METHODS: We examined 227 consecutive unconscious patients after CPR and excluded 1 individual. The decision to administer selenium was left to the discretion of the attending physician, resulting in 124 patients (55%) who received intravenous selenium (200-1000 microg/d) for a median of 5 days after CPR. Patients were classified according to the best Glasgow-Pittsburgh cerebral performance categories (CPCs 1-5) achieved within 6 months of follow-up. RESULTS: The rate of regaining consciousness (CPC 1-3) after CPR was 58%. Multivariable logistic regression analysis confirmed a shockable first monitored rhythm (adjusted odds ratio, 3.73; 95% confidence interval, 1.85-7.52; P < .001), time to return of spontaneous circulation (adjusted odds ratio, 0.94; 95% confidence interval, 0.91-0.96; P < .001), administration of selenium (adjusted odds ratio, 2.38; 95% confidence interval, 1.19-4.76; P = .014), and the Simplified Acute Physiology Score II (adjusted odds ratio, 0.96; 95% confidence interval, 0.93-0.99; P = .034) as independent predictors of regaining consciousness after CPR. Survival at 6 months of follow-up was not improved significantly by selenium. CONCLUSION: This retrospective analysis leads to the hypothesis that early administration of selenium may improve neurological outcome after cardiac arrest.

Doping of metal-organic frameworks towards resistive sensing.

Coordination polymerization leads to various metal-organic frameworks (MOFs) with unique physical properties and chemical functionalities. One of the challenges towards their applications as porous materials is to make MOFs optimally conductive to be used as electronic components. Here, it is demonstrated that Co-MOF-74, a honeycomb nano-framework with one-dimensionally arranged cobalt atoms, advances its physical properties by accommodating tetracyanochinodimethan (TCNQ), an acceptor molecule. Strong intermolecular charge transfer reduces the optical band gap down to 1.5 eV of divalent TCNQ and enhances the electrical conduction, which allows the MOF to be utilized for resistive gas- and photo-sensing. The results provide insight into the electronic interactions in doped MOFs and pave the way for their electronic applications.

Nickel clusters embedded in carbon nanotubes as high performance magnets.

Ensembles of fcc nickel nanowires have been synthesized with defined mean sizes in the interior of single-wall carbon nanotubes. The method allows the intrinsic nature of single-domain magnets to emerge with large coercivity as their size becomes as small as the exchange length of nickel. By means of X-ray magnetic circular dichroism we probe electronic interactions at nickel-carbon interfaces where nickel exhibit no hysteresis and size-dependent spin magnetic moment. A manifestation of the interacting two subsystems on a bulk scale is traced in the nanotube's magnetoresistance as explained within the framework of weak localization.

Multicentre analysis of 178,992 type 2 diabetes patients revealed better metabolic control despite higher rates of hypertension, stroke, dementia and repeated inpatient care in patients with comorbid Parkinson's disease.

BACKGROUND: Especially in older people, physicians are faced with the coexistence of type 2 diabetes mellitus (T2DM) and Parkinson's disease (PD). Therefore, this research aimed to compare diabetes endpoints between T2DM with and without PD. METHODS: Based on the standardized, multicenter, prospective DPV database, 178,992 T2DM patients (≥40 years) were analyzed. 1579 were diagnosed with PD and/or received specific treatment. Hierarchical multivariable regression models were used for group comparisons; adjusted estimates based on observed marginal frequencies were calculated. RESULTS: PD patients were significantly older (77.9 vs. 70.0 years; p < 0.0001) and had a longer diabetes duration (10.3 vs. 8.4 years; p < 0.0001). In young PD patients (<50 years), percentage of females was significantly higher compared to age-matched T2DM patients without PD or people of the German population (66.7 vs. 38.1 vs. 49.0%; p < 0.0001, p < 0.02). After demographic adjustment, T2DM patients with PD showed a significantly lower HbA1c (58.0 vs. 60.3 mmol/mol; p < 0.0001), OAD/GLP-1 treatment (41.9 vs. 45.9%; p < 0.01) and frequency of dyslipidemia (62.0 vs. 64.5%; p < 0.05). In contrast, rates of insulin therapy (57.8 vs. 54.8%; p < 0.05), hypertension (73.3 vs. 68.6%; p < 0.001), antihypertensive medication (60.4 vs. 56.1%; p < 0.01), stroke (12.0 vs. 7.3%; p < 0.0001), dementia (9.2 vs. 2.6%; p < 0.0001) and repeated inpatient care (15.7 vs. 12.0%; p < 0.0001) were significantly higher and duration of hospital stay (6.2 vs. 4.7 days; p < 0.0001) was significantly longer in T2DM with PD. CONCLUSION: Clear demographic and clinical differences were observed between T2DM with and without PD. In PD patients, metabolic control is better, potentially due to more intensive medical care.

Prediction of neurological outcome after cardiopulmonary resuscitation by serial determination of serum neuron-specific enolase.

AIMS: Data on the diagnostic accuracy of neuron-specific enolase (NSE) as marker of hypoxic brain damage are conflicting. The purpose of this prospective observational cohort study was to explore the prognostic value of serum NSE after cardiopulmonary resuscitation (CPR) and to define the most sensitive cutoff value with a specificity of 100% for the prediction of persistent coma. METHODS AND RESULTS: Serum NSE concentrations were serially determined in 227 consecutive unconscious patients after CPR who were classified according to the best Glasgow-Pittsburgh cerebral performance categories (CPC, 1-4) achieved within 6 months follow-up. Sixteen patients were excluded due to incomplete NSE data and 34 due to death under analgesia sedation. The prevalence of poor neurological outcome (persistent coma, CPC 4) in our 177 analysed patients was 33%. At a specificity of 100%, a peak NSE concentration above 80 ng/mL predicted persistent coma with a sensitivity of 63%, a positive predictive value of 100%, a negative predictive value of 84%, and a predictive accuracy of 88%. CONCLUSION: A peak serum NSE concentration exceeding 80 ng/mL is a highly specific but only moderately sensitive marker for a poor neurological outcome after CPR.

Flecainide versus ibutilide for immediate cardioversion of atrial fibrillation of recent onset.

AIMS: This study compared the efficacy and safety of intravenous flecainide and ibutilide for immediate cardioversion of atrial fibrillation (AF). METHODS AND RESULTS: We conducted a prospective, randomised trial, including 207 patients with AF of recent onset (< or = 48 h). Flecainide was given over 20 min at a dose of 2 mg/kg body weight (maximum 200 mg), ibutilide was infused at a dose of 1 mg (or 0.01 mg/kg if less than 60 kg) over 10 min, followed by a 10 min observation period and an identical second dose if AF did not convert to sinus rhythm (SR). Treatment was considered successful if SR occurred within 90 min of starting medication. The conversion rates were 56.4% in patients given flecainide and 50.0% in patients given ibutilide (P=0.34). Multivariate analysis revealed that a lower age for women independently increased the probability of conversion. None of the other variables, including left atrial size, left ventricular systolic function, presence of left ventricular hypertrophy, plasma levels of potassium or magnesium at baseline, or concomitant use of digoxin, beta-blocker, diltiazem or verapamil were predictors of conversion. The frequency of adverse events was comparable in the two treatment groups. CONCLUSIONS: There was no significant difference in the cardioversion efficacy or in the risk of adverse events between flecainide and ibutilide in patients with AF of recent onset. In patients without contraindications to both medications, the physician's choice has to be governed by other factors.