Thermally stable mesoporous tetragonal zirconia through surfactant-controlled synthesis and Si-stabilization

Thermally stable, highly mesoporous Si-stabilized ZrO₂ was prepared by sol–gel-synthesis. By utilizing the surfactant dodecylamine (DDA), large mesopores with a pore width of ∼9.4 nm are formed. Combined with an NH₃-treatment on the hydrogel, a high specific surface area of up to 225 m² g⁻¹ and pore volume up to 0.46 cm³ g⁻¹ are obtained after calcination at 973 K. The individual contributions of Si-addition, DDA surfactant and the NH₃-treatment on the resulting pore system were studied by inductively coupled plasma with optical emission spectrometry (ICP-OES), X-ray diffraction (XRD), N₂ sorption, and transmission electron microscopy (TEM). Electron tomography was applied to visualize and investigate the mesopore network in 3D space. While Si prevents the growth of ZrO₂ crystallites and stabilizes the t-ZrO₂ phase, DDA generates a homogeneous mesopore network within the zirconia. The NH₃-treatment unblocks inaccessible pores, thereby increasing specific surface area and pore volume while retaining the pore width distribution.

Schematic representation of ZrO₂ crystallites; (a) monoclinic ZrO₂, (b) tetragonal ZrO₂ following Si-stabilization, (c) mesoporous t-ZrO₂ following Si-stabilization and use of surfactant dodecylamine.     

Using measures of reading time regularity (RTR) to quantify eye movement dynamics,and how they are shaped by linguistic information

In this article, we present the concept of reading time regularity (RTR) as a measure to capture reading process dynamics. The first study is concerned with examining one of the assumptions of RTR, namely, that process measures of reading, such as eye movement fluctuations and fixation durations, exhibit higher regularity when contingent on sequentially structured information, such as texts. To test this, eye movements of 26 German native speakers were recorded during reading-unrelated and reading-related tasks. To analyze the data, we used recurrence quantification analysis and sample entropy analysis to quantify the degree of temporal structure in time series of gaze steps and fixation durations. The results showed that eye movements become more regular in reading compared to nonreading conditions. These effects were most prominent when calculated on the basis of gaze step data. In a second study, eye movements of 27 native speakers of German were recorded for five conditions with increasing linguistic information. The results replicate the findings of the first study, verifying that these effects are not due to mere differences in task instructions between conditions. Implications for the concept of RTR and for future studies using these metrics in reading research are discussed.     

Use of Fertility Preservation Among a Cohort of Transgirls in the Netherlands

Purpose

The primary aims of the study are to examine the rate of attempted fertility preservation (FP) among a Dutch cohort of transgirls who started gonadotropin-releasing hormone analog treatment and the reasons why adolescents did or did not choose to attempt FP.

High‐dimensional propensity score algorithm in comparative effectiveness research with time‐varying interventions

The high‐dimensional propensity score (hdPS) algorithm was proposed for automation of confounding adjustment in problems involving large healthcare databases. It has been evaluated in comparative effectiveness research (CER) with point treatments to handle baseline confounding through matching or covariance adjustment on the hdPS. In observational studies with time‐varying interventions, such hdPS approaches are often inadequate to handle time‐dependent confounding and selection bias. Inverse probability weighting (IPW) estimation to fit marginal structural models can adequately handle these biases under the fundamental assumption of no unmeasured confounders. Upholding of this assumption relies on the selection of an adequate set of covariates for bias adjustment. We describe the application and performance of the hdPS algorithm to improve covariate selection in CER with time‐varying interventions based on IPW estimation and explore stabilization of the resulting estimates using Super Learning. The evaluation is based on both the analysis of electronic health records data in a real‐world CER study of adults with type 2 diabetes and a simulation study. This report (i) establishes the feasibility of IPW estimation with the hdPS algorithm based on large electronic health records databases, (ii) demonstrates little impact on inferences when supplementing the set of expert‐selected covariates using the hdPS algorithm in a setting with extensive background knowledge, (iii) supports the application of the hdPS algorithm in discovery settings with little background knowledge or limited data availability, and (iv) motivates the application of Super Learning to stabilize effect estimates based on the hdPS algorithm. Copyright © 2014 John Wiley & Sons, Ltd.     

Evolution of thrombolytic therapy in patients with HeartWare ventricular assist device thrombosis: a single-institutional experience

Open in a separate window OBJECTIVESPump thrombosis remains a major challenge in heart failure patients with left ventricular HeartWare assist device. Current International Society for Heart and Lung Transplantation recommendations favour surgical pump exchange over lysis because safety and efficacy of lysis has been controversially reported. This study summarizes our experience on our HeartWare thrombosis prevention strategy as well as thrombolysis through implementation of our institutional standardized HeartWare assist device protocol.METHODSOutcomes of all HeartWare thrombosis patients admitted between 2010 and 2020 were analysed. Thrombolysis therapy using tissue plasminogen activator was used as the first-line therapy in this study and thrombolysis therapy efficacy was defined as freedom from stroke, bleeding, recurrent HeartWare assist device thrombosis or surgical device exchange within 30 days after lysis application.RESULTSA total of 507 patients have been included in this study and 66 patients (13%) collectively developed a first HeartWare-thrombosis after a median of 12 months (8–22 months) after HeartWare implantation. Forty patients were treated with unstandardized lysis, of whom 7 patients had thrombolysis associated complications, such as incomplete thrombus resolution requiring surgical pump exchange in 4 patients, but also intracranial haemorrhage occurring in 3 patients. Three patients died in the non-protocol group. Eight device thrombosis patients were treated according to our protocol, showing no lysis-associated complication.CONCLUSIONSDespite current recommendations, preferring surgical HeartWare pump exchange in thrombosis, thrombolysis therapy for first HeartWare thrombosis can be safe and effective in a standardized protocol setting, including anticoagulation adjustment and intensified blood pressure control management.     

Neural processing associated with cognitive empathy in pedophilia and child sexual offending

Behavioral studies found evidence for superior cognitive empathy (CE) in pedophilic men without a history of child sexual offending (P − CSO) compared to pedophilic men with a history of child sexual offending (P + CSO). Functional magnetic resonance imaging (fMRI) studies also point to differences between P − CSO and P + CSO. Neural processing associated with CE has not yet been investigated. Therefore, the present study aimed to explore the neural correlates of CE in subjects with pedophilia with (P + CSO) and without (P − CSO) child sexual offending. 15 P + CSO, 15 P − CSO and 24 teleiophilic male controls (TC) performed a CE task during fMRI. We observed reduced activation in the left precuneus (Pcu) and increased activation in the left anterior cingulate cortex (ACC) in P − CSO compared to P + CSO. P − CSO also showed stronger connectivity between these regions, which might reflect a top-down modulation of the Pcu by the ACC toward an increased self-focused emotional reaction in social situations. There was also evidence for increased right superior temporal gyrus activation in P − CSO that might constitute a potentially compensatory recruitment due to the dampened Pcu activation. These findings provide first evidence for altered neural processing of CE in P − CSO and underline the importance of addressing CE in pedophilia and CSO in order to uncover processes relevant to effective prevention of child sexual abuse.     

Fulminant Adenoviral-Induced Hepatitis in Immunosuppressed Patients

Human adenovirus (HAdV) can often lead to fulminant hepatitis in immunocompromised patients, mostly after reactivation of HAdV. Different risk factors, e.g., transplantation and chemotherapy, increase the risk of developing a HAdV hepatitis. We retrospectively analyzed three patients who showed the characteristics of a HAdV hepatitis observed in disseminated disease. In addition to PCR, diagnosis could be proven by pathology, CT scan, and markedly elevated transaminases. All patients had a hemato-oncologic underlying disease. Two had received a stem-cell transplant, and one was under chemotherapy including rituximab. Despite therapy with cidofovir, all patients died. As the incidence of HAdV hepatitis is low, diagnosis may be easily overlooked. No treatment approaches have yet been established. HAdV hepatitis should be considered as a differential diagnosis, especially when risk factors are present. To avoid dissemination, treatment should be initiated as soon as possible.     

Prevention of acute exacerbation of chronic obstructive pulmonary disease after bronchoscopic lung volume reduction with endobronchial valves

IntroductionBronchoscopic lung volume reduction (BLVR) with endobronchial valves (EBVs) has emerged as an important treatment method for patients with severe chronic obstructive pulmonary disease (COPD). Acute exacerbations of COPD (AECOPD) are a frequent complication following BLVR with EBV. However, there is no consensus on the prevention of AECOPD.ObjectivesOur study aims to compare the outcomes of different prophylactic measures on the occurrence of AECOPD after BLVR with EBV.MethodsWe conducted a multicenter, retrospective study of patients who underwent BLVR with EBV at six different institutions. Emphasis was directed towards the specific practices aimed at preventing AECOPD: antibiotics, steroids, antibiotics plus steroids, or no prophylaxis. Subgroups were compared, and odds ratios (ORs) with corresponding 95% confidence intervals (CIs) were calculated.ResultsA total of 170 patients were reviewed. The rate of AECOPD was 21.2% for the full cohort. Patients who received prophylaxis had a significantly lower rate of AECOPD compared with those who did not (16.7% vs. 46.2%; p = 0.001). The rate was lowest in patients who received antibiotics alone (9.2%). There was no significant difference in the rate of AECOPD between patients who received steroids alone or antibiotics plus steroids, compared with the other subgroups. The OR for AECOPD was 4.3 (95% CI: 1.8–10.4; p = 0.001) for patients not receiving prophylaxis and 3.9 (95% CI: 1.5–10.1; p = 0.004) for prophylaxis other than antibiotics alone.ConclusionsAdministration of antibiotics after BLVR with EBV was associated with a lower rate of AECOPD. This was not observed with the use of steroids or in combination with antibiotics.     

Comparison of Melting Processes for WPC and the Resulting Differences in Thermal Damage,Emissions and Mechanics

The necessity for resource-efficient manufacturing technologies requires new developments within the field of plastic processing. Lightweight design using wood fibers as sustainable reinforcement for thermoplastics might be one solution. The processing of wood fibers requires special attention to the applied thermal load. Even at low processing temperatures, the influence of the dwell time, temperature and shear force is critical to ensure the structural integrity of fibers. Therefore, this article compares different compounding rates for polypropylene with wood fibers and highlights their effects on the olfactory, visual and mechanical properties of the injection-molded part. The study compares one-step processing, using an injection-molding compounder (IMC), with two-step processing, using a twin-scew-extruder (TSE), a heating/cooling mixer (HCM) and an internal mixer (IM) with subsequent injection molding. Although the highest fiber length was achieved by using the IMC, the best mechanical properties were achieved by the HCM and IM. The measured oxidation induction time and volatile organic compound content indicate that the lowest amount of thermal damage occurred when using the HCM and IM. The advantage of one-time melting was evened out by the dwell time. The reinforcement of thermoplastics by wood fibers depends more strongly on the structural integrity of the fibers compared to their length and homogeneity.