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Behavioral effects of continuous theta-burst stimulation in macaque parietal cortex
The neural mechanisms underlying the effects of continuous Theta-Burst Stimulation (cTBS) in humans are poorly understood. Animal studies can clarify the effects of cTBS on individual neurons, but behavioral evidence is necessary to demonstrate the validity of the animal model. We investigated the behavioral effect of cTBS applied over parietal cortex in rhesus monkeys performing a visually-guided grasping task with two differently sized objects, which required either a power grip or a pad-to-side grip. We used Fitts’ law, predicting shorter grasping times (GT) for large compared to small objects, to investigate cTBS effects on two different grip types. cTBS induced long-lasting object-specific and dose-dependent changes in GT that remained present for up to two hours. High-intensity cTBS increased GTs for a power grip, but shortened GTs for a pad-to-side grip. Thus, high-intensity stimulation strongly reduced the natural GT difference between objects (i.e. the Fitts’ law effect). In contrast, low-intensity cTBS induced the opposite effects on GT. Modifying the coil orientation from the standard 45-degree to a 30-degree angle induced opposite cTBS effects on GT. These findings represent behavioral evidence for the validity of the nonhuman primate model to study the neural underpinnings of non-invasive brain stimulation.Fonds voor Wetenschappelijk Onderzoek Vlaanderen, Odysseus (G.0007.12, G.0C51.13N)
The Photodetector Array Camera and Spectrometer (PACS) on the Herschel Space Observatory
The Photodetector Array Camera and Spectrometer (PACS) is one of the three
science instruments on ESA's far infrared and submillimetre observatory. It
employs two Ge:Ga photoconductor arrays (stressed and unstressed) with 16x25
pixels, each, and two filled silicon bolometer arrays with 16x32 and 32x64
pixels, respectively, to perform integral-field spectroscopy and imaging
photometry in the 60-210\mu\ m wavelength regime. In photometry mode, it
simultaneously images two bands, 60-85\mu\ m or 85-125\mu\m and 125-210\mu\ m,
over a field of view of ~1.75'x3.5', with close to Nyquist beam sampling in
each band. In spectroscopy mode, it images a field of 47"x47", resolved into
5x5 pixels, with an instantaneous spectral coverage of ~1500km/s and a spectral
resolution of ~175km/s. We summarise the design of the instrument, describe
observing modes, calibration, and data analysis methods, and present our
current assessment of the in-orbit performance of the instrument based on the
Performance Verification tests. PACS is fully operational, and the achieved
performance is close to or better than the pre-launch predictions
An industry consensus study on an HPLC fluorescence method for the determination of (±)-catechin and (±)-epicatechin in cocoa and chocolate products
<p>Abstract</p> <p>Background</p> <p>This manuscript describes the results of an HPLC study for the determination of the flavan-3-ol monomers, (±)-catechin and (±)-epicatechin, in cocoa and plain dark and milk chocolate products. The study was performed under the auspices of the National Confectioners Association (NCA) and involved the analysis of a series of samples by laboratories of five member companies using a common method.</p> <p>Methodology</p> <p>The method reported in this paper uses reversed phase HPLC with fluorescence detection to analyze (±)-epicatechin and (±)-catechin extracted with an acidic solvent from defatted cocoa and chocolate. In addition to a variety of cocoa and chocolate products, the sample set included a blind duplicate used to assess method reproducibility. All data were subjected to statistical analysis with outliers eliminated from the data set.</p> <p>Results</p> <p>The percent coefficient of variation (%CV) of the sample set ranged from approximately 7 to 15%.</p> <p>Conclusions</p> <p>Further experimental details are described in the body of the manuscript and the results indicate the method is suitable for the determination of (±)-catechin and (±)-epicatechin in cocoa and chocolate products and represents the first collaborative study of this HPLC method for these compounds in these matrices.</p
Effectiveness of a nurse-supported self-management programme for dual sensory impaired older adults in long-term care:A cluster randomised controlled trial
Objective To evaluate the effectiveness of a nurse supported self-management programme to improve social participation of dual sensory impaired older adults in long-term care homes. Design Cluster randomised controlled trial. Setting Thirty long-term care homes across the Netherlands. Participants Long-term care homes were randomised into intervention clusters (n=17) and control clusters (n=13), involving 89 dual sensory impaired older adults and 56 licensed practical nurses. Intervention Nurse-supported self-management programme. Measurements Effectiveness was evaluated by the primary outcome social participation using a participation scale adapted for visually impaired older adults distinguishing four domains: instrumental activities of daily living, social-cultural activities, high physical-demand and low-physical-demand leisure activities. A questionnaire assessing hearing-related participation problems was added as supportive outcome. Secondary outcomes were autonomy, control, mood and quality of life and nurses' job satisfaction. For effectiveness analyses, linear mixed models were used. Sampling and intervention quality were analysed using descriptive statistics. Results Self-management did not affect all four domains of social participation; however. the domain 'instrumental activities of daily living' had a significant effect in favour of the intervention group (P=0.04; 95% CI 0.12 to 8.5). Sampling and intervention quality was adequate. Conclusions A nurse-supported self-management programme was effective in empowering the dual sensory impaired older adults to address the domain 'instrumental activities of daily living', but no differences were found in addressing the other three participation domains. Self-management showed to be beneficial for managing practical problems, but not for those problems requiring behavioural adaptations of other persons
Lysine acetylation regulates the interaction between proteins and membranes
Lysine acetylation regulates the function of soluble proteins in vivo, yet it remains largely unexplored whether lysine acetylation regulates membrane protein function. Here, we use bioinformatics, biophysical analysis of recombinant proteins, live-cell fluorescent imaging and genetic manipulation of Drosophila to explore lysine acetylation in peripheral membrane proteins. Analysis of 50 peripheral membrane proteins harboring BAR, PX, C2, or EHD membrane-binding domains reveals that lysine acetylation predominates in membrane-interaction regions. Acetylation and acetylation-mimicking mutations in three test proteins, amphiphysin, EHD2, and synaptotagmin1, strongly reduce membrane binding affinity, attenuate membrane remodeling in vitro and alter subcellular localization. This effect is likely due to the loss of positive charge, which weakens interactions with negatively charged membranes. In Drosophila, acetylation-mimicking mutations of amphiphysin cause severe disruption of T-tubule organization and yield a flightless phenotype. Our data provide mechanistic insights into how lysine acetylation regulates membrane protein function, potentially impacting a plethora of membrane-related processes
Self-management for dual sensory impaired older adults: an effective approach?
A cRCT was performed in 30 Dutch long-term care homes between 2011-2014, involving 89 dual sensory impaired older adults and 56 licensed practical nurses. The long=term care homes were randomly assigned into intervention clusters (n=17) and control clusters (n=13). The older adults of the intervention cluster received a nurse-supported self-management program spread over a period of 5 months, the older adults of the control group received usual care.
Effectiveness was evaluated by the primary outcome social participation. Secondary outcomes were autonomy, control, mood and quality of life.
The self-management program was successful in empowering the dual sensory impaired older adults to address instrumental daily living problems, but failed to address other domains of social participation. Process evaluation revealed key barriers to their engaging in social interaction.
The dataset presents (1) the statistical data on the primary and secondary outcomes, measuring the effectiveness of the program, and (2) the qualitative data collected from the intervention diaries of the nurses, reflecting the problems and wishes identified by the dual sensory impaired older adults
Problems identified by dual sensory impaired older adults in long-term care when using a self-management program: A qualitative study
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170080.pdf (publisher's version ) (Open Access)OBJECTIVE: To gain insights into the problems of dual sensory impaired older adults in long-term care. Insights into these problems are essential for developing adequate policies which address the needs of the increasing population of dual sensory impaired older adults in long-term care. METHODS: A qualitative study was conducted in parallel with a cluster randomized controlled trial. Dual sensory impaired older adults in the intervention group (n = 47, age range 82-98) were invited by a familiar nurse to identify the problems they wanted to address. Data were taken from the semi-structured intervention diaries in which nurses noted the older adults' verbal responses during a five-month intervention period in 17 long-term care homes across the Netherlands. The data were analyzed using descriptive statistics and qualitative content analysis based on the Grounded Theory. FINDINGS: The 47 dual sensory impaired older adults identified a total of 122 problems. Qualitative content analysis showed that the older adults encountered participation problems and problems controlling what happens in their personal environment. Three categories of participation problems emerged: (1) existential concerns of not belonging or not being able to connect with other people, (2) lack of access to communication, information and mobility, and (3) the desire to be actively involved in care delivery. Two categories of control-in-personal-space problems emerged: (1) lack of control of their own physical belongings, and (2) lack of control regarding the behavior of nurses providing daily care in their personal environment. CONCLUSIONS: The invasive problems identified indicate that dual sensory impaired older adults experience great existential pressures on their lives. Long-term care providers need to develop and implement policies that identify and address these problems, and be aware of adverse consequences of usual care, in order to improve dual sensory impaired residents' autonomy and quality of life
Growth and Characterization of Vanadium Dioxide/Niobium Doped Titanium Dioxide Heterostructures for Ultraviolet Detection
Characteristics of InAS(0.8)Sb(0.2) photodetectors on GaAs substrates
As an alternative to HgCdTe, InAsxSb1-x is an important alloy providing bandgaps suitable for infrared detection in both 3-5 and 8-12 mum atmospheric windows. There has been interest in high-quality growth of this material on GaAs and Si substrates. This paper reports the fabrication and characteristics of mid-infrared InAs0.8Sb0.2 photodetectors grown on GaAs substrates by molecular beam epitaxy. Peak detectivities of 1.4 x 10(10) and 7.5 x 10(8) cm Hz(1/2) W-1 were measured at 77 K and 240 K. respectively. showing that the alloy is promising as an alternative to thermal detectors for near room temperature operation. A detailed analysis of the dark current showed that the reverse-bias differential resistance was limited by trap-assisted tunneling in a wide temperature range up to 150 K under low and moderately large reverse bias voltages. Noise measurements have shown that trap assisted tunneling is the source of I If noise which is increased with the addition of band to band tunneling under large reverse bias. Our observations on InAs0.8Sb0.2 photodiodes show resemblance to those reported for HgCdTe detectors. The results are encouraging for the development of mid-infrared large area focal plane arrays on GaAs substrates
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