154 research outputs found
The impact of an interventional counselling procedure in families with a BRCA1/2 gene mutation : efficacy and safety
Background: Predictive genetic testing has high impact on cancer prevention for BRCA carriers and passing this information in BRCA families is important. Mostly, this is proband-mediated but this path is defective and denies relatives lifesaving information.
Objective: To assess the efficacy/safety of an intervention, in which relatives are actively informed.
Design: Sequential prospective study in new BRCA families. The proband informed relatives about predictive testing (phase I). After 6 months, a letter was sent to adult relatives who had not been reached (phase II). Then a phone call was made to obtain a final notion of their wishes. All subjects received psychometric testing (State-Trait Anxiety Inventory, STAI), an interview and routine counselling.
Results: Twenty families were included. Twenty-four of the relatives could not be reached, 59 were 'decliners', 47 participated by the proband and 42 by the letter. Predictive testing was performed in 98 % of the participants of which 30 were mutation carriers. The intervention is psychologically safe: the 95 % CI for the estimated mean difference in STAI DY1 between phase II/I subjects (mean difference -1.07, 95 % CI -4.4 to 2.35, p = 0.53) shows that the mean STAI DY1 score (measured at first consult) for phase II is no more than 2.35 units higher than for phase I, which is not relevant.
Conclusions: A protocol directly informing relatives nearly doubles the number of relatives tested and is psychologically safe. This should lead to a change in counselling guidelines in families with a strong germline predisposition for cancer
Quantification of epidermal growth factor receptor T790M mutant transcripts in lung cancer cells by real-time reverse transcriptase-quantitative polymerase chain reaction.
peer reviewedA simple and sensitive real-time reverse transcriptase-quantitative polymerase chain reaction (RT-qPCR) was developed to quantify threonine-to-methionine substitution at amino acid position 790 (T790M) mutant transcripts in a wild-type (wt) epidermal growth factor receptor background. The assay is based on three unmodified oligonucleotides, and both SYBR Green and a Taqman probe can be used. To increase the discrimination between mutant and wt signals, ARMS (amplification refractory mutation system) and LNA (locked nucleic acid) primers were tested, but a benefit was observed only with plasmids and not with cellular complementary DNA. The RT-qPCR assay using transcript-specific primers can detect as few as 1% T790M transcripts in a wt background and, therefore, will be useful in RNA interference studies specifically targeting mutant RNA
Graphene-based thermopneumatic generator for on-board pressure supply of soft robots
Various fields, including medical and human interaction robots, gain
advantages from the development of bioinspired soft actuators. Many recently
developed grippers are pneumatics that require external pressure supply
systems, thereby limiting the autonomy of these robots. This necessitates the
development of scalable and efficient on-board pressure generation systems.
While conventional air compression systems are hard to miniaturize,
thermopneumatic systems that joule-heat a transducer material to generate
pressure present a promising alternative. However, the transducer materials of
previously reported thermopneumatic systems demonstrate high heat capacities
and limited surface area resulting in long response times and low operation
frequencies. This study presents a thermopneumatic pressure generator using
aerographene, a highly porous (>99.99 %) network of interconnected graphene
microtubes, as lightweight and low heat capacity transducer material. An
aerographene pressurizer module (AGPM) can pressurize a reservoir of 4.2 cm3 to
about ~140 mbar in 50 ms. Periodic operation of the AGPM for 10 s at 0.66 Hz
can further increase the pressure in the reservoir to ~360 mbar. It is
demonstrated that multiple AGPMs can be operated parallelly or in series for
improved performance. For example, three parallelly operated AGPMs can generate
pressure pulses of ~215 mbar. Connecting AGPMs in series increases the maximum
pressure achievable by the system. It is shown that three AGPMs working in
series can pressurize the reservoir to ~2000 mbar in about 2.5 min. The AGPM's
minimalistic design can be easily adapted to circuit boards, making the concept
a promising fit for the on-board pressure supply of soft robots.Comment: Author Affiliation: Functional Nanomaterials, Department of Materials
Science, Kiel University, Germany; Corresponding Authors: Dr.-Ing. Fabian
Sch\"utt ([email protected]), Prof. Dr. Rainer Adelung ([email protected]
On the plasma permeability of highly porous ceramic framework materials using polymers as marker materials
Highly porous framework materials are of large interest due to their broad potential for application, for example, as sensors or catalysts. A new approach is presented to investigate, how deep plasma species can penetrate such materials. For this purpose, a polymer (ethylene propylene diene monomere rubber) is used as marker material and covered with the porous material during plasma exposure. Water contact-angle and X-ray photoelectron spectroscopy measurements are used to identify changes in the polymer surface, originating from the interaction of plasma species with the polymer. The method is demonstrated by studying the plasma permeability of tetrapodal zinc oxide framework materials with a porosity of about 90% in an oxygen low-pressure capacitively coupled plasma. Significant differences in the penetration depth ranging from roughly 1.6–4 mm are found for different densities of the material and different treatment conditions
Metrics Pipeline (Codename): An Analytics and Visualization Pipeline for Software Quality Metrics
The Metrics Pipeline (Codename) focuses on metrics indicative of team progress and project health instead of privileging individual metrics, e.g. number of commits, etc. The Metrics Dashboard allows the user to submit the URL of a hosted repository for batch analysis, whose results are then cached. Upon completion, the user can interactively study various metrics over time (at varying granularity), numerically, and visually. The initial version of the system is up and running as a public cloud service (SaaS) and supports project size (KLOC), defect density, defect spoilage, and productivity. While our system is by no means the first to support software metrics, we believe it may be one of the first community-focused extensible resources that can be used by any hosted project
Multifunctional, Self-Cleaning Air Filters Based on Graphene-Enhanced Ceramic Networks
Particulate air pollution is taking a huge toll on modern society, being
associated with more than three million deaths per year. In addition, airborne
infectious microorganism can spread dangerous diseases, further elevating the
problem. A common way to mitigate the risks of airborne particles is by air
filtration. However, conventional air filters usually do not provide any
functionality beyond particle removal. They are unable to inactivate
accumulated contaminants and therefore need periodic maintenance and
replacement to remain operational and safe. This work presents a
multifunctional, self-cleaning air filtration system which utilizes a novel
graphene-enhanced air filter medium (GeFM). The hybrid network of the GeFM
combines the passive structure-based air filtration properties of an underlying
ceramic network with additional active features based on the functional
properties of a graphene thin film. The GeFM is able to capture >95 % of
microorganisms and particles larger than 1 m and can be repetitively
Joule-heated to >300 {\deg}C for several hours without signs of degradation.
Hereby, built-up organic particulate matter and microbial contaminants are
effectively decomposed, regenerating the GeFM. Additionally, the GeFM provides
unique options to monitor the filter's air troughput and loading status during
operation. The active features of the GeFM can drastically improve filter
life-time and safety, offering great potential for the development of safer and
more sustainable air filtration solutions to face the future challenges of air
pollution and pandemics.Comment: * Corresponding authors: Prof. Dr. Rainer Adelung ([email protected])
and Dr.-Ing. Fabian Sch\"utt ([email protected]
Extended spin coherence of the zinc-vacancy centers in ZnSe with fast optical access
Qubits based on crystal defect centers have been shown to exhibit long spin coherence times, up to seconds at room temperature. However, they are typically characterized by a comparatively slow initialization timescale. Here, fluorine implantation into ZnSe epilayers is used to induce defect states that are identified as zinc vacancies. We study the carrier spin relaxation in these samples using various pump-probe measurement methods, assessing phenomena such as resonant spin amplification, polarization recovery, and spin inertia in transverse or longitudinal magnetic field. The spin dynamics in isotopically natural ZnSe show a significant influence of the nuclear spin bath. Removing this source of relaxation by using isotopic purification, we isolate the anisotropic exchange interaction as the main spin dephasing mechanism and find spin coherence times of 100 ns at room temperature, with the possibility of fast optical access on the picosecond time scales through excitonic transitions of ZnSe
The Stellar and Gas Kinematics of the LITTLE THINGS Dwarf Irregular Galaxy NGC 1569
In order to understand the formation and evolution of dIm galaxies, one needs
to understand their three-dimensional structure. We present measurements of the
stellar velocity dispersion in NGC 1569, a nearby post-starburst dIm galaxy.
The stellar vertical velocity dispersion, , coupled with the
maximum rotational velocity derived from \ion{H}{1} observations, , gives a measure of how kinematically hot the galaxy is, and, therefore,
indicates its structure. We conclude that the stars in NGC 1569 are in a thick
disk with a = 2.4 0.7. In addition to the
structure, we analyze the ionized gas kinematics from \ion{O}{3} observations
along the morphological major axis. These data show evidence for outflow from
the inner starburst region and a potential expanding shell near supermassive
star cluster (SSC) A. When compared to the stellar kinematics, the velocity
dispersion of the stars increase in the region of SSC A supporting the
hypothesis of an expanding shell. The stellar kinematics closely follow the
motion of the gas. Analysis of high resolution \ion{H}{1} data clearly reveals
the presence of an \ion{H}{1} cloud that appears to be impacting the eastern
edge of NGC 1569. Also, an ultra-dense \ion{H}{1} cloud can be seen extending
to the west of the impacting \ion{H}{1} cloud. This dense cloud is likely the
remains of a dense \ion{H}{1} bridge that extended through what is now the
central starburst area. The impacting \ion{H}{1} cloud was the catalyst for the
starburst, thus turning the dense gas into stars over a short timescale,
1 Gyr. We performed a careful study of the spectral energy distribution using
infrared, optical, and ultraviolet photometry producing a state-of-the-art mass
model for the stellar disk. This mass modeling shows that stars dominate the
gravitational potential in the inner 1 kpc.Comment: 49 pages, 25 figures, accepted in A
How do professionals perceive the governance of public–private partnerships? Evidence from Canada, the Netherlands and Denmark
In public–private partnerships (PPPs), the collaboration between public and private actors can be complicated. With partners coming from different institutional backgrounds and with different interests, governing these partnerships is important to ensure the projects' progress. There is, however, little knowledge about the perceptions of professionals regarding the governance of PPPs. This study aims to exlore professionals' viewpoints about governing PPPs, and to explain potential differences using four theoretical governance paradigms. Using Q methodology, the preferences of 119 public and private professionals in Canada, the Netherlands and Denmark are explored. Results show four different viewpoints regarding the governance of PPPs. Experience, country and the public–private distinction seem to influence these viewpoints. Knowledge of these differences can inform efforts to govern PPPs and contribute to more successful partnerships
Biomechanical effects of rocker shoes on plantar aponeurosis strain in patients with plantar fasciitis and healthy controls
Plantar fasciitis is a frequently occurring overuse injury of the foot. Shoes with a stiff rocker profile are a commonly prescribed treatment modality used to alleviate complaints associated with plantar fasciitis. In rocker shoes the apex position was moved proximally as compared to normal shoes, limiting the progression of the ground reaction forces (GRF) and peak plantarflexion moments during gait. A stiff sole minimizes dorsiflexion of the toes. The aim of this study was to investigate whether the biomechanical effects of rocker shoes lead to minimization of plantar aponeurosis (PA) strain during gait in patients with plantar fasciitis and in healthy young adults. 8 patients with plantar fasciitis (1 male, 7 females; mean age 55.0 ± 8.4 years) and 8 healthy young adults (8 females; mean age 24.1 ± 1.6 years) participated in the study. Each participant walked for 1 minute on an instrumented treadmill while wearing consecutively in random order shoes with a normal apex position (61.2 ± 2.8% apex) with flexible insole (FN), normal apex position with stiff insole (SN), proximal apex position (56.1 ± 2.6% apex) with flexible insole (FR) and proximal apex position with stiff insole (SR). Marker position data of the foot and lower leg and GRF were recorded. An OpenSim foot model was used to compute the change in PA length based on changes in foot segment positions during gait. The changes in PA length due to increases in Achilles tendon forces were computed based on previous data of a cadaver study. PA strain computed from both methods was not statistically different between shoe conditions. Peak Achilles tendon force, peak first metatarsophalangeal (MTP1) joint angle and peak plantarflexion moment were significantly lower when walking with the rocker shoe with a proximal apex position and a stiff insole for all subjects (p<.05). Changes in Achilles tendon forces during gait accounted for 65 ± 2% of the total PA strain. Rocker shoes with a stiff insole reduce peak dorsiflexion angles of the toes and plantar flexion moments, but not PA strain because the effects of a proximal apex position and stiff insole do not occur at the same time, but independently affect PA strain at 80-90% and 90-100% of the stance phase. Rocker shoes with an apex position of ~56% are insufficient to significantly reduce peak PA strain values in patients with plantar fasciitis and healthy young adults
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