1,200 research outputs found
A method for mechanical generation of radio frequency fields in nuclear magnetic resonance force microscopy
We present an innovative method for magnetic resonance force microscopy
(MRFM) with ultra-low dissipation, by using the higher modes of the mechanical
detector as radio frequency (rf) source. This method allows MRFM on samples
without the need to be close to an rf source. Furthermore, since rf sources
require currents that give dissipation, our method enables nuclear magnetic
resonance experiments at ultra-low temperatures. Removing the need for an
on-chip rf source is an important step towards a MRFM which can be widely used
in condensed matter physics.Comment: 7 pages, 5 figures, to be submitted to Physical Review Applie
How is participation related to well-being of homeless people?:An explorative qualitative study in a Dutch homeless shelter facility
The majority of homeless people is socially excluded which negatively affects their well-being. Therefore, participation-based programs are needed. The current research is conducted within a Dutch homeless shelter facility that offers educational, recreational, and labor activities to clients in an environment which is designed to feel safe (an enabling niche). The main aim of these activities is to facilitate social participation. We conducted two qualitative studies consisting of 16 semi-structured interviews, to explore clientsâ experiences with participation in activities in relation to their well-being. The findings showed that clients experienced that participation had led to an improvement of physical, social, and mental well-being. In general, clients reported that due to participation in activities they have strengthened their social support network, improved their (mental and physical) health, self-esteem and personal growth. We concluded that in order to facilitate long-term positive outcomes of participation in practice, it is necessary to focus on group cohesion, and on the social workerâs behavior and attitud
Derivatives. Replication and (auto)plagiarism in the social sciences
This working paper reports on the travelling exhibition âDerivativesâ. This exhibition investigates the issue of originality in the context of (self) plagiarism and replication. The different views in the Arts and the scientific discourse form the point of departure for discovering how ideas that are identical can still be completely different and new, but also that âoriginalâ works of art can be repetitive reproduction
Probing the magnetic moment of FePt micromagnets prepared by Focused Ion Beam milling
We investigate the degradation of the magnetic moment of a 300 nm thick FePt
film induced by Focused Ion Beam (FIB) milling. A rod is milled out of a film by a FIB process and is attached
to a cantilever by electron beam induced deposition. Its magnetic moment is
determined by frequency-shift cantilever magnetometry. We find that the
magnetic moment of the rod is , which implies that 70% of the magnetic moment is preserved
during the FIB milling process. This result has important implications for atom
trapping and magnetic resonance force microscopy (MRFM), that are addressed in
this paper.Comment: 4 pages, 4 figure
Mid-range visual deficits after stroke:Prevalence and co-occurrence
Visual deficits are common after stroke and are powerful predictors for the chronic functional outcome. However, while basic visual field and recognition deficits are relatively easy to assess with standardized methods, selective deficits in visual primitives, such as shape or motion, are harder to identify, as they often require a symmetrical bilateral posterior lesion in order to provoke full field deficits. Therefore, we do not know how often they occur. Nevertheless, they can have severe repercussions for daily-life functioning. We aimed to investigate the prevalence and co-occurrence of hemifield âmid-rangeâ visual deficits (i.e. color, shape, location, orientation, correlated motion, contrast, texture and glossiness), using a novel experimental set-up with a gaze-contingent presentation of the stimuli. To this end, a prospective cohort of 220 ischemic (sub)cortical stroke patients and a healthy control group was assessed with this set-up. When comparing performance of patients with controls, the results showed that deficits in motion-perception were most prevalent (26%), followed by color (22%), texture (22%), location (21%), orientation (18%), contrast (14%), shape (14%) and glossiness (13%). 63% of the stroke patients showed one or more mid-range visual deficits. Overlap of deficits was small; they mostly occurred in isolation or co-occurred with only one or two other deficits. To conclude, it was found that deficits in âmid-rangeâ visual functions were very prevalent. These deficits are likely to affect the chronic post-stroke condition. Since we found no strong patterns of co-occurrences, we suggest that an assessment of deficits at this level of visual processing requires screening the full range of visual functions
Self-referring patients at the emergency department: appropriateness of ED use and motives for self-referral
© 2014, van der Linden et al.; licensee Springer. Background: Nearly all Dutch citizens have a general practitioner (GP), acting as a gatekeeper to secondary care. Some patients bypass the GP and present to the emergency department (ED). To make best use of existing emergency care, Dutch health policy makers and insurance companies have proposed the integration of EDs and GP cooperatives (GPCs) into one facility. In this study, we examined ED use and assessed the characteristics of self-referrals and non-self-referrals, their need for hospital emergency care and self-referrals' motives for presenting at the ED. Methods: A descriptive cohort study was conducted in a Dutch level 1 trauma centre. Differences in patient characteristics, time of presentation and need for hospital emergency care were analysed using Ï2 tests and t tests. A patient was considered to need hospital emergency care when he/she was admitted to the hospital, had an extremity fracture and/or when diagnostic tests were performed. Main determinants of self-referral were identified via logistic regression. Results: Of the 5,003 consecutive ED patients registering within the 5-week study period, 3,028 (60.5%) were self-referrals. Thirty-nine percent of the self-referrals had urgent acuity levels, as opposed to 65% of the non-self-referrals. Self-referrals more often suffered from injuries (49 vs. 20%). One third of the self-referrals presented during office hours. Of all self-referrals, 51% needed hospital emergency care. Younger age; non-urgent acuity level; chest pain, ear, nose or throat problems; and injuries were independent predictors for self-referral. Most cited motives for self-referring were âaccessibility and convenienceâ and perceived âmedical necessityâ. Conclusions: A substantial part of the self-referrals needed hospital emergency care. The 49% self-referrals who were eligible for GP care presented during out-of-hours as well as during office hours. This calls for an integrative approach to this health care problem
Norditerpenoids with selective anti-cholinesterase activity from the roots of Perovskia atriplicifolia Benth
Inhibition of cholinesterases remains one of a few available treatment strategies for neurodegenerative dementias such as Alzheimer's disease and related conditions. The current study was inspired by previous data on anticholinesterase properties of diterpenoids from Perovskia atriplicifolia and other Lamiaceae species. The acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibition by the three new natural compounds-(1R,15R)-1-acetoxycryptotanshinone (1), (1R)-1-acetoxytanshinone IIA (2), and (15R)-1-oxoaegyptinone A (3)-as well as, new for this genus, isograndifoliol (4) were assessed. Three of these compounds exhibited profound inhibition of butyrylcholinesterase (BChE) and much weaker inhibition of acetylcholinesterase (AChE). All compounds (1-4) selectively inhibited BChE (IC(50) = 2.4, 7.9, 50.8, and 0.9 ”M, respectively), whereas only compounds 3 and 4 moderately inhibited AChE (IC(50) 329.8 ”M and 342.9 ”M). Molecular docking and in silico toxicology prediction studies were also performed on the active compounds. Natural oxygenated norditerpenoids from the traditional Central Asian medicinal plant P. atriplicifolia are selective BChE inhibitors. Their high potential makes them useful candidate molecules for further investigation as lead compounds in the development of a natural drug against dementia caused by neurodegenerative diseases
Adaptability and learning Intraprofessional collaboration of residents during the COVID-19 pandemic
CONTEXT: The COVID-19 pandemic created a worldwide public health emergency, in which hospitals created new COVID departments and doctors from different disciplines had to work together. In the Netherlands, a large proportion of doctors in these departments were residents. With knowledge of the disease developing only gradually, the influx of COVID-19 patients called for adaptability, innovative work behavior, and intraprofessional collaboration (intraPC) between residents and between residents and medical specialists. RESEARCH GOAL: This study investigates how the delivery of COVID-19 care in hospital settings altered the way residents develop their sense of adaptability and intraPC during their training. METHODS: Sixteen semi-structured interviews were conducted with residents and medical specialists from various disciplines who worked at a COVID department or Intensive Care Unit (ICU) during the COVID pandemic in the Netherlands, focusing on adaptability and intraPC learning. Transcripts were analyzed using (thematic) template analysis. RESULTS: Four themes that influenced learning during COVID care were identified: collective uncertainty, social cohesion and a sense of safety, the need for adaptive performance and intraPC learning. During the first wave, collective uncertainty about the unknown disease and the continuation of the crisis urged residents to adapt in order to take care of patients with a disease that was as yet unknown. The combination of collective uncertainty, social cohesion and a sense of safety, and the presence of different disciplines in one department promoted residentsâ intraPC learning. However, intraPC learning was not always the matter of course due to the scope of the crisis and the huge numbers of new patients. CONCLUSION: Collective uncertainty affected the residentsâ adaptability. The combination of collective uncertainty, social cohesion, and the presence of different disciplines in one department promoted the residentsâ intraPC learning. An important facilitating factor for both adaptability and intraPC learning is a high level of social cohesion and safety. The physical and psychological proximity of supervisors is an important factor contributing to a safe learning environment. This study provides implications for practice for learning during postgraduate training in non-crisis settings. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12909-022-03868-9
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