A new semiconducting perovskite alloy system made possible by gas-source molecular beam epitaxy

We demonstrate epitaxial thin film growth of the chalcogenide perovskite semiconducting alloy system BaZrS$_{(3-y)}$Se$_y$ using gas-source molecular beam epitaxy (MBE). BaZrS$_3$ is stable in the perovskite structure in bulk form, but the pure selenide BaZrSe$_3$ is not. Here stabilize the full range of compositions y = 0 ... 3 in the perovskite structure, up to and including BaZrSe$_3$, by growing on BaZrS$_3$ buffer layers. The alloy grows by pseudomorphic heteroepitaxy on the sulfide buffer, without interruption in the reflection high energy electron diffraction (RHEED) pattern. The resulting films are environmentally stable and the direct band gap (E$_g$) varies strongly with Se content, as predicted by theory, covering the range E$_g$ = 1.9 ... 1.4 eV for y = 0 ... 3. This creates possibilities for visible and near-infrared (VIS-NIR) optoelectronics, solid state lighting, and solar cells using chalcogenide perovskites

Not Pregnant Now in almost two-thirds of all municipalities in The Netherlands

Het programma Nu Niet Zwanger is gericht op het voorkomen van onbedoelde zwangerschappen bij mensen in kwetsbare omstandigheden. Hulpverleners in het sociaal en medisch domein gaan daartoe tijdens reguliere contactmomenten met hun eigen cliënten (m/v) in gesprek over hun kinderwens. Ze ondersteunen hen bij het maken van een geïnformeerde en vrijwillige keuze, en bieden desgewenst begeleiding bij het kiezen en het realiseren van anticonceptie. Onderzoek laat zien dat de ervaringen van hulpverleners en cliënten met Nu Niet Zwanger positief zijn en leverde ook verbeterpunten op. Begin 2023 wordt het programma in bijna twee derde van de gemeenten in Nederland uitgevoerd en ligt de focus op structurele, landelijke borging.The program Not Pregnant Now aims to prevent unintended pregnancies in vulnerable populations. To this end, care providers start an openconversation during regular social and healthcare visits with their clients about their desire to have children. They support their clients in making an informed and voluntary decision about this and, ifwanted, offer support in choosing and realizing contraception. Research showed that the experiences of the care providers and clients with the program arepositive and also resulted in recommendations for improvement. At the beginning of 2023, the program runs in three quarters of the municipalities in TheNetherlands and the focus is on structural, national maintenance

Evaluation of a dedicated dual phased-array surface coil using a black-blood FSE sequence for high resolution MRI of the carotid vessel wall

Purpose: To investigate the ability of magnetic resonance imaging (MRI) to visualize the carotid vessel wall using a phased-array coil and a black-blood (BB) fast spin-echo (FSE) sequence. Materials and Methods: The phased-array coil was compared with a three-inch coil. Images from volunteers were evaluated for artifacts, wall layers, and wall signal intensity. Signal intensity and homogeneity of atherosclerosis were assessed. Lumen diameter and vessel area were measured. Results: Comparison between the phased-array coil and the three-inch coil showed a 100% increase in signal-to-noise ratio. BB-FSE imaging resulted in good delineation between blood and vessel wall. Most volunteers had a two-layered vessel wall with a hyperintense inner layer. MRI showed both homogeneous hyperintense and heterogeneous plaques, which consisted of a main hyperintense part with hypointense spots and/or intermediate regions. MRI lumen and area measurements were performed easily. Conclusion: High resolution MRI of carotid atherosclerosis is feasible with a phased-array coil and a BB-FSE sequence

Accurate assessment of abdominal aortic aneurysm with intravascular ultrasound scanning: Validation with computed tomographic angiography

AbstractPurpose: The purpose of this study was to assess the accuracy of intravascular ultrasound (IVUS) parameters of abdominal aortic aneurysm, used for endovascular grafting, in comparison with computed tomographic angiography (CTA). Methods: This study was designed as a descriptive study. Between March 1997 and March 1998, 16 patients with abdominal aortic aneurysms were studied with angiography, IVUS (12.5 MHz), and CTA. The length of the aneurysm and the length and lumen diameter of the proximal and distal neck obtained with IVUS were compared with the data obtained with CTA. The measurements with IVUS were repeated by a second observer to assess the reproducibility. Tomographic IVUS images were reconstructed into a longitudinal format. Results: IVUS results identified 31 of 32 renal arteries and four of five accessory renal arteries. A comparison of the length measurements of the aneurysm and the proximal and distal neck obtained with IVUS and CTA revealed a correlation of 0.99 (P < .001), with a coefficient of variation of 9%. IVUS results tended to underestimate the length as compared with the CTA results (0.48 ± 0.52 cm; P < .001). A comparison of the lumen diameter measurements of the proximal and distal neck derived from IVUS and CTA showed a correlation of 0.93 (P < .001), with a coefficient of variation of 9%. IVUS results tended to underestimate aneurysm neck diameter as compared with CTA results (0.68 ± 1.76 mm; P = .006). Interobserver agreement of IVUS length and diameter measurements showed a good correlation (r = 1.0; P < .001), with coefficients of variation of 3% and 2%, respectively, and no significant differences (0.0 ± 0.16 cm and 0.06 ± 0.36 mm, respectively). The longitudinal IVUS images displayed the important vascular structures and improved the spatial insight in aneurysmal anatomy. Conclusion: Intravascular ultrasound scanning results provided accurate and reproducible measurements of abdominal aortic aneurysm. The longitudinal reconstruction of IVUS images provided additional knowledge on the anatomy of the aneurysm and its proximal and distal neck. (J Vasc Surg 1999;29:631-8.

Endovascular repair versus open surgery in patients with ruptured abdominal aortic aneurysms: Clinical outcomes with 1-year follow-up

ObjectiveTo compare the clinical outcomes of treatment after endovascular repair and open surgery in patients with ruptured infrarenal abdominal aortic aneurysms (AAAs), including 1-year follow-up.MethodsAll consecutive conscious patients with ruptured infrarenal AAAs who presented to our tertiary care teaching hospital between January 1, 2001, and December 31, 2005, were included in this study (n = 55). Twenty-six patients underwent endovascular repair, and 29 patients underwent open surgery. Patients who were hemodynamically too unstable to undergo a computed tomography angiography scan were excluded. Outcomes evaluated were intraoperative mortality, 30-day mortality, systemic complications, complications necessitating surgical intervention, and mortality and complications during 1-year follow-up. The statistical tests we used were the Student t test, χ2 test, Fisher exact test, and Mann-Whitney U test (two sided; α = .05).ResultsThirty-day mortality was 8 (31%) of 26 patients who underwent endovascular repair and 9 (31%) of 29 patients who underwent open surgery (P = .98). Systemic complications and complications necessitating surgical intervention during the initial hospital stay were similar in both treatment groups (8/26 [31%] and 5/26 [19%] for endovascular repair, respectively, and 9/29 [31%] and 8/29 [28%] for open surgery, respectively; P > .40). During 1-year follow-up, two patients initially treated with endovascular repair died as a result of non–aneurysm-related causes; no death occurred in the open surgery group. Complications during 1-year follow-up were 1 (5%) of 20 for endovascular repair and 4 (16%) of 25 for open surgery (P = .36).ConclusionsOn the basis of our study with a highly selected population, the mortality and complication rates after endovascular repair may be similar compared with those after open surgery in patients treated for ruptured infrarenal AAAs

Performance of the BioIntegral Bovine Pericardial Graft in Vascular Infections:VASCular No-REact Graft Against INfection Study

Background: Vascular graft and endograft infections (VGEI) and native vessel infections (NVI) remain considerable challenges in vascular surgery, leading to high mortality and morbidity rates. Although in situ reconstruction is the preferred treatment, the material of choice is still a source of debate. Autologous veins are considered the first choice; however, xenografts may be an acceptable alternative. The performance of a biomodified bovine pericardial graft is assessed when implemented in an infected vascular area. Methods: This is a prospective multicenter cohort study. Patients who underwent reconstruction for VGEI or NVI with a biomodified bovine pericardial bifurcated or straight tube graft were included from December 2017 until June 2021. The primary outcome measure was reinfection at mid-term follow-up. Secondary outcome measures included mortality, patency, and amputation rate. Results: Thirty-four patients with vascular infections were included, of which 23 (68%) had an infected Dacron prosthesis after primary open repair and 8 (24%) had an infected endovascular graft. The remaining 3 (9%) had infected native vessels. At secondary repair, 3 (7%) patients had an in situ aortic tube reconstruction, 29 (66%) had an aortic bifurcated reconstruction, and 2 (5%) had an iliac-femoral reconstruction. At 1-year follow-up after the BioIntegral bovine pericardial graft reconstruction, the reinfection rate was 9%. The 1-year infection-related and procedure-related mortality rate was 16%. The occlusion rate was 6% and in total 3 patients underwent a lower limb amputation during the 1-year follow-up period. Conclusions: In situ reconstruction as treatment of (endo)graft and native vessel infections remains a challenge and reinfection looms as a potential consequence. In cases where time is of essence or when autologous venous repair is not feasible, a swift available solution is needed. The BioIntegral biomodified bovine pericardial graft may be an option as it shows reasonable results in terms of reinfection, in aortic tube and bifurcated grafts.</p

A Damage Mechanics Approach to Life Prediction for a Salt Structure

Excavated rooms in natural bedded salt formations are being considered for use as repositories for nuclear waste. It is presumed that deformation of the rooms by creep will lead to loss of structural integrity and affect room life history and seal efficiency. At projected repository temperatures, two possible fracture mechanisms in salt are creep-induced microcracking in triaxial compression and cleavage in tension. Thus, an accurate prediction of room life and seal degradation requires a reliable description of the creep and damage processes. While several constitutive models that treat either creep or fracture in salt are available in the literature, very few models have considered creep and damage in a coupled manner. Previously, Munson and Dawson formulated a set of creep equations for salt based on the consideration of dislocation mechanisms in the creep process. This set of creep equations has been generalized to include continuum, isotropic damage as a fully coupled variable in the response equation. The extended model has been referred to as the Multimechanism Deformation Coupled Fracture (MDCF) model. A set of material constants for the creep and damage terms was deduced based on test data for both clean and argillaceous salt. In this paper, the use of the MDCF model for establishing the failure criteria and for analyzing the creep response of a salt structure is demonstrated. The paper is divided into three parts. A summary of the MDCF model is presented first, which is followed by an evaluation of the MDCF model against laboratory data. Finally, finite-element calculations of the creep and damage response of a salt structure are presented and compared against in-situ field measurements

The year in cardiology 2014: peripheral circulation.

In 2014, the debate on the indication of revascularization in case of asymptomatic carotid disease continued, while another one regarding the use of surgery vs. stenting addressed some new issues regarding the long-term cardiac risk of these patients. Renal arteries interventions trials were disappointing, as neither renal denervation nor renal artery stenting was found associated with better blood pressure management or outcome. In contrast, in lower-extremities artery disease, the endovascular techniques represent in 2014 major alternatives to surgery, even in distal arteries, with new insights regarding the interest of drug-eluting balloons. Regarding the aorta, the ESC published its first guidelines document on the entire vessel, emphasizing on the role of every cardiologist for screening abdominal aorta aneurysm during echocardiography. Among vascular wall biomarkers, the aorta stiffness is of increasing interest with new data and meta-analysis confirming its ability to stratify risk, whereas carotid intima-media thickness showed poor performances in terms of reclassifying patients into risk categories beyond risk scores. Regarding the veins, new data suggest the interest of D-dimers and residual venous thrombosis to help the decision of anti-coagulation prolongation or discontinuation after the initial period of treatment for deep vein thrombosis