119 research outputs found
The evolutionary status of the bright high-latitude supergiant HD190390
Despite its mean apparent magnitude of m(v)=6.39, the evolutionary status of
HD190390 (HR7671), a luminous F-type supergiant at high galactic latitude, is
still not very clear, but in most papers a post-AGB classification is assumed.
New observational material has been obtained with four different instruments
and is presented here. An extensive abundance analysis based on high
resolution, high signal-to-noise NTT+EMMI spectra confirms the metal deficiency
of this object ([Fe/H]=-1.6), together with a high lithium content
(log(Li)=1.9). A variability analysis based on Geneva photometry over seven
years reveals beating with a period of +/-3000 days. It is, however, not clear
whether this beating is caused by a stable triplet, or it is the consequence of
small changes in the main frequency. More recent data obtained with the
HIPPARCOS satellite and the Mercator telescope not only confirm the main
period, but also support the presence of a second periodicity of 11 days, which
was also found in the Geneva photometry. A conclusive evolutionary status of
this object is not given, but alternative to the UU Her (i.e. post-AGB) status,
a W Vir classification is discussed.Comment: 14 pages, 13 figures, accepted for publication in A&
Choosing treatment for prostate cancer:Information provision, quality of life, and use of an online decision aid
Samen beslissen over de behandeling van prostaatkanker Prostaatkanker is meest voorkomende kankersoort bij mannen. Per jaar wordt bij ongeveer 10.000 Nederlandse mannen deze diagnose gesteld. In ongeveer driekwart van de gevallen is er sprake van gelokaliseerde prostaatkanker, waarbij de kanker nog niet is uitgezaaid buiten de prostaat. In dat geval zijn er meerdere gelijkwaardige behandelingen mogelijk. Behandelingen kunnen gericht zijn op genezing, of er kan worden gekozen om het verloop van de ziekte af te wachten en pas te behandelen als daar aanleiding voor is. Genezende behandelingen geven een risico op bijwerkingen (oa. impotentie en incontinentie) die erger kunnen zijn dan de klachten van de prostaatkanker. Met actief volgen worden deze behandelbijwerkingen uitgesteld, of vermeden, maar het geeft ook een risico dat te lang wordt gewacht waardoor geen genezende behandeling meer mogelijk is. Om de best passende behandeling te kiezen, is het belangrijk dat een arts en patiënt samen alle opties afwegen en daarbij rekening houden met de persoonlijke kenmerken en voorkeuren van de patiënt. Om dit gezamenlijke proces van samen beslissen te ondersteunen is er een online keuzehulp ontwikkeld die patiënten met prostaatkanker kunnen raadplegen. Het proefschrift Choosing treatment for Prostate cancer – Information provision, quality of life, and the use of an online decision aid, van Maarten Cuypers beschrijft de ontwikkeling en evaluatie van deze keuzehulp. De keuzehulp geeft informatie over alle behandelopties, inclusief actief volgen, en besteed evenwichtig aandacht aan de voor- en nadelen van alle opties. Daarnaast legt de keuzehulp een aantal stellingen voor aan de patiënt, die helpen bij het uitspreken van een voorkeur voor een bepaalde optie. Aan het einde geeft de keuzehulp een samenvatting met de belangrijkste overwegingen van de patiënt, die kan worden besproken met de arts. Implementatie van de keuzehulp in de dagelijkse praktijk en evaluatie door patiënten en zorgverleners werd onderzocht in een cluster gerandomiseerde trial, waarbij 9 ziekenhuizen de keuzehulp opnamen in het zorgpad, en 9 andere ziekenhuizen de gebruikelijke zorg verleenden. Patiënten vulden vragenlijsten in direct na de behandelkeuze, en 6 en 12 maanden later. De resultaten lieten zien dat patiënten en zorgverleners de keuzehulp positief beoordeelde op oa. gebruiksgemak. De keuzehulp werd door de meeste patiënten gebruikt en ook de samenvatting werd besproken met de arts. Er werden echter geen effecten van de keuzehulp op keuzeconflict of kennisniveau gevonden, en direct na de behandelbeslissing bleken patiënten uit de keuzehulpgroep minder tevreden met ontvangen informatie dan patiënten uit de controlegroep. Na 12 maanden werden geen verschillen in tevredenheid meer gevonden, en waren patiënten uit beide studiegroepen even tevreden. Ook waren de meeste patiënten na 12 maanden tevreden met hun behandeling en werd er weinig spijt gerapporteerd, ongeacht of de keuzehulp was gebruikt. Implementatie van de keuzehulp bleek moeizaam. Gemiddeld werd aan 35% van nieuwe prostaatkankerpatiënten een keuzehulp uitgereikt binnen de ziekenhuizen die deelnamen aan de studie. Tussen ziekenhuizen onderling werden grote verschillen in implementatie gevonden. In een aantal ziekenhuizen lag de implementatiegraad boven 80%, terwijl ook een aantal ziekenhuizen aan minder dan 10% van de patiënten een keuzehulp uitgereikte. Om implementatie te bevorderen zouden zorgverleners meer getraind moeten worden in gebruik van de keuzehulp, en zouden onderdelen van de huidige keuzehulp meer toegepast moeten worden tijdens consulten dan nu het geval was
Identifying the deficits in cancer care for people with intellectual disabilities
No abstract available
Polyimide-ald-polyimide layers as hermetic encapsulant for implants
Several requirements exist for medical devices for long term implantation. Firstly, the foreign body reaction and/or inflammation occurring upon implantation should remain mild and short in time. Moreover, the device needs to be biocompatible during the total implantation duration, hence not causing reactions which decrease the patient’s health. Finally, the device needs to work properly and safe during the total period of implantation, not suffering from corrosion or chemical degradation. To meet these requirements, diffusion of body fluids into the package should be avoided as well as diffusion of toxic device materials into the body, hence a hermetic packaging method is an absolute necessity. Here, a flexible hermetic packaging is presented using alternating polyimide and atomic layer deposited (ALD) metal oxides. Good adhesion between the inorganic ALD layers and the polyimide is required to avoid the creation of lateral diffusion pads. To obtain this, surface modifications of both polyimide and ALD layers are optimized, as presented in this paper. The hermeticity is evaluated in terms of water vapor transmission rate measurements of the film stack
The use of ALD layers for hermetic encapsulation in the development of a flexible implantable micro electrode for neural recording and stimulation
The use of electronic microsystems as medical implants gains interests due to the combination of superior device functionality with extreme miniaturization. Electronic devices are not biocompatible and will suffer from corrosion, hence a very good hermetic device encapsulation is of utmost importance. The hermetic sealing of implantable electronics requires extremely good bi-directional barrier properties against diffusion of water, ions and gases.
Moreover, extremely long biostability against body fluids and biomolecules is an important requirement for the
barrier materials. In this work, an ALD multilayer of AlOx and HfOx in combination with flexible polyimide is
used as a flexible hermetic encapsulation of an electronic CMOS chip which serves as an implantable probe (so called hd TIME (active high-density transverse intrafascicular microelectrode) probe) for neural recording and stimulation [1]. The main part consists of a 35μm thin CMOS chips with electrodes on top encapsulated with alternating layers of spin coated polyimide (PI2611) and biocompatible ALD layers.
The total encapsulation is developed to provide excellent barrier properties. Each ALD stack (ALD-3) consists of AlOx (20 nm) capped on both sides with HfOx (8 nm) to avoid hydrolysis of AlOx. The ALD deposition
temperature is 250°C. Special attention is payed to the adhesion of the ALD layers toward polyimide and vice versa.
3 to 4 PI/ALD-3 dyads are used for the total encapsulation, since long term implantation of the medical device is envisaged. Testing however is done using only a part of the total encapsulation, in order to enable to learn about the barrier properties in a reasonnable timeframe. The WVTR of a PI/ALD-3/PI film reached a value of 2.1 10-5 g/m2day (38°C and 100% RH), the total encapsulation with 3 to 4 dyads will lead to WVTR’s in the order of 10-6g/m2day.
The same PI/ALD-3/PI film has been deposited on structured copper meanders and is exposed to PBS at 60°C for 3.5 years (equivalent to 17.5 years at 37°C) [2]. Up till now, no change in Cu resistivity has been observed proving the excellent barrier properties of the PI/ALD-3/PI film.
[1] Rik Verplancke et al., 2020 J. Micromech. Microeng., 30, 015010
[2] Changzheng Li et al. 2019 Coatings, 9, 57
Technological advances for analyzing the content of organ-on-a-chip by mass spectrometry
Three-dimensional (3D) cell cultures, including organ-on-a-chip (OOC) devices, offer the possibility to mimic human physiology conditions better than 2D models. The organ-on-a-chip devices have a wide range of applications, including mechanical studies, functional validation, and toxicology investigations. Despite many advances in this field, the major challenge with the use of organ-on-a-chips relies on the lack of online analysis methods preventing the real-time observation of cultured cells. Mass spectrometry is a promising analytical technique for real-time analysis of cell excretes from organ-on-a-chip models. This is due to its high sensitivity, selectivity, and ability to tentatively identify a large variety of unknown compounds, ranging from metabolites, lipids, and peptides to proteins. However, the hyphenation of organ-on-a-chip with MS is largely hampered by the nature of the media used, and the presence of nonvolatile buffers. This in turn stalls the straightforward and online connection of organ-on-a-chip outlet to MS. To overcome this challenge, multiple advances have been made to pre-treat samples right after organ-on-a-chip and just before MS. In this review, we summarised these technological advances and exhaustively evaluated their benefits and shortcomings for successful hyphenation of organ-on-a-chip with MS
Differences in treatment choices between prostate cancer patients using a decision aid and patients receiving care as usual:Results from a randomized controlled trial
Contains fulltext :
241596.pdf (Publisher’s version ) (Open Access
Matrix metalloproteinases as candidate biomarkers in adults with congenital heart disease
Context Matrix metalloproteinases (MMPs) are associated with diastolic dysfunction and heart failure in acquired heart disease. Objective To investigate the role of MMPs as novel biomarkers in clinically stable adults with congenital heart disease. Methods We measured serum MMP-2, -3, -9 and tissue inhibitor of matrix metalloproteinase-1 in 425 patients and analysed the association with cardiac function and exercise capacity. Results MMP-2 was significantly associated with exercise capacity, ventilatory efficiency and left ventricular deceleration time, independently of age, sex, body surface area and NT-proBNP. Conclusion MMP-2 may provide new information in the clinical evaluation of adults with congenital heart disease
Prognostic value of serial N-terminal pro-B-type natriuretic peptide measurements in adults with congenital heart disease
Background--A single NT-proBNP (N-terminal pro-B-type natriuretic peptide) measurement is a strong prognostic factor in adult congenital heart disease. This study investigates NT-proBNP profiles within patients with adult congenital heart disease and relates these to cardiovascular events. Methods and Results--In this prospective cohort, 602 patients with adult congenital heart disease were enrolled at the outpatient clinic (years 2011-2013). NT-proBNP was measured at study inclusion in 595 patients (median age 33 [IQR 25-41] years, 58% male, 90% NYHA I) and at subsequent annual visits. The primary end point was defined as death, heart failure, hospitalization, arrhythmia, thromboembolic event, or cardiac intervention; the secondary end point as death or heart failure. Repeated measurements were analyzed using linear mixed models and joint models. During a median follow-up of 4.4 [IQR 3.8-4.8] years, a total of 2424 repeated measurements were collected. Average NT-proBNP increase was 2.9 pmol/L the year before the primary end point (n=199, 34%) and 18.2 pmol/L before the secondary end point (n=58, 10%), compared with 0.3 pmol/L in patients who remained end point-free (P-value for difference in slope 0.006 and < 0.
Low-temperature and low-voltage, solution-processed metal oxide n-TFTs and flexible circuitry on large-area polyimide foil
In this article, we report on high-performance solution-based n-type metal oxide TFTs processed directly on polyimide foil and annealed at 250 °C. Saturation mobilities exceeding 2 cm²/(Vs) and Ion/Ioff ratios beyond 108 have been achieved. Using these oxide n-TFTs, fast and low-voltage flexible circuitry is presented. Furthermore, a complete 8-bit RFID transponder chip, containing 294 oxide n-TFTs has been fabricated. Both high-speed and low-voltage operation makes the presented oxide n-TFT technology suited for both the pixel driving and embedded line-drive circuitry at the borders of flexible AMOLED displays
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