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Objective. After stroke, people experience difficulties with walking that lead to restrictions in participation in daily life. The purpose of this study was to examine the effect of virtual reality gait training (VRT) compared to non-virtual reality gait training (non-VRT) on participation in community-living people after stroke. Methods. In this assessor-blinded, randomized controlled trial with 2 parallel groups, people were included between 2 weeks and 6 months after stroke and randomly assigned to the VRT group or non-VRT group. Participants assigned to the VRT group received training on the Gait Real-time Analysis Interactive Lab (GRAIL), and participants assigned to the non-VRT group received treadmill training and functional gait exercises without virtual reality. Both training interventions consisted of 12 30-minute sessions during 6 weeks. The primary outcome was participation measured with the restrictions subscale of the Utrecht Scale for Evaluation of Rehabilitation-Participation (USER-P) 3 months postintervention. Secondary outcomes included subjective physical functioning, functional mobility, walking ability, dynamic balance, walking activity, fatigue, anxiety and depression, falls efficacy, and quality of life. Results. Twenty-eight participants were randomly assigned to the VRT group and 27 to the non-VRT group, of whom 25 and 22 attended 75% or more of the training sessions, respectively. No significant differences between the groups were found over time for the USER-P restrictions subscale (1.23; 95% CI = - 0.76 to 3.23) or secondary outcome measures. Patients' experiences with VRT were positive, and no serious adverse events were related to the interventions. Conclusions. The effect of VRT was not statistically different from non-VRT in improving participation in community-living people after stroke. Impact. Although outcomes were not statistically different, treadmill-based VRT was a safe and well-tolerated intervention that was positively rated by people after stroke. VR training might, therefore, be a valuable addition to stroke rehabilitation. Lay Summary. VRT is feasible and was positively experienced by people after stroke. However, VRT was not more effective than non-VRT for improving walking ability and participation after stroke. Keywords: Gait, Gait Training, Participation, Rehabilitation, Stroke, Virtual Reality, Introduction Although a substantial number of people after stroke regain the physical capacity to walk without support from others, many still experience difficulties with walking in the community and performing [...]

Background. Virtual reality (VR) training is considered to be a promising novel therapy for balance and gait recovery in patients with stroke. Purpose. The aim of this study was to conduct a systematic literature review with meta-analysis to investigate whether balance or gait training using VR is more effective than conventional balance or gait training in patients with stroke. Data Sources. A literature search was carried out in the databases PubMed, Embase, MEDLINE, and Cochrane Library up to December 1, 2015. Study Selection. Randomized controlled trials that compared the effect of balance or gait training with and without VR on balance and gait ability in patients with stroke were included. Data Extraction and Synthesis. Twenty-one studies with a median PEDro score of 6.0 were included. The included studies demonstrated a significant greater effect of VR training on balance and gait recovery after stroke compared with conventional therapy as indicated with the most frequently used measures: gait speed, Berg Balance Scale, and Timed 'Up & Go' Test. Virtual reality was more effective to train gait and balance than conventional training when VR interventions were added to conventional therapy and when time dose was matched. Limitations. The presence of publication bias and diversity in included studies were limitations of the study. Conclusions. The results suggest that VR training is more effective than balance or gait training without VR for improving balance or gait ability in patients with stroke. Future studies are recommended to investigate the effect of VR on participation level with an adequate follow-up period. Overall, a positive and promising effect of VR training on balance and gait ability is expected., Many patients with stroke experience sensory, motor, cognitive, and visual impairments, which all have an impact on their ability to perform daily life activities. (1,2) Approximately 80% of patients with [...]

OBJECTIVE--Several national and international scoring systems are used to diagnose diabetic polyneuropathy (PNP). The variety in these scores and the lack of data on validity and predictive value has led [...]

OBJECTIVE -- To evaluate the discriminative power of the Diabetic Neuropathy Symptom (DNS) and Diabetic Neuropathy Examination (DNE) scores for diagnosing diabetic polyneuropathy (PNP), as well as their relation with [...]

Effective methods to generate colour centres in diamond and other wide band-gap materials are essential to the realisation of solid state quantum technologies based on such systems. Such methods have been the subject of intensive research effort in recent years. In this review, we bring together the various techniques used in the generation and positioning of colour centres in diamond: ion implantation, delta-doping, electron irradiation, laser writing and thermal annealing. We assess the roles and merits of each of these techniques in the formation of colour centres for different quantum technologies and consider future combinations of the techniques to meet the requirements of the most demanding applications.

OBJECTIVE - Existing physical examination scoring systems for distal diabetic polyneuropathy (PNP) do not fulfill all of the following criteria: validity, manageability predictive value, and hierarchy. The aim of this [...]

An integrated magnetic sensor is designed and tested that utilizes the negatively charged nitrogen vacancy centers (NVC) in diamond as a magnetic field‐sensitive quantum material, which is accessed and readout solely optically. The compact sensor device features a side length of 10 mm and includes a small HPHT diamond slab, light‐emitting diode (LED) for excitation, and integrated photodiodes. A microwave‐free approach is used. With the device, DC sensitivity to magnetic fields of 49 nA mT−1in the range of 5–50 mT is achieved. The sensor device is also capable of detecting very small magnetic fields: Magnetic field dependencies at very low flux densities in the μT range (zero‐magnetic field) show a characteristic fluorescence behavior revealing a sensitivity of 4.8 pA μT−1. Additionally, a ray‐tracing model is applied, to identify loss mechanisms in the setup. Using this device, an ultracompact, reliable, and industry‐ready package is made available for sensor developments in industry and academia. An integrated magnetic sensor is designed and tested that utilizes the negatively charged nitrogen vacancy centers (NVC) in diamond as a magnetic field‐sensitive quantum material. The compact sensor device features a side length of 10 mm and includes a small HPHT diamond slab featuring NVC, LED for excitation, and integrated photodiodes. A microwave‐free approach is used.

The nanometer‐scale engineering of single nitrogen‐vacancy (NV) centres in diamond can be obtained by low‐energy (keV) nitrogen implantation with limited straggling. However, shallow NV centres (a few nanometres deep) generally have inferior overall properties than deeply implanted or deep native NV centres, due to the surface proximity. It has already been shown that the spin coherence time of shallow NVs is improved by overgrowth of a thin diamond layer. However the influence of the overgrowth on the survival, the optical properties and the charge state of the centres has not been studied in detail. In this article, we have overgrown three diamond samples (containing NV centres implanted at different depths) using different procedures. We show the successful overgrowth of a pattern of very shallow (2 nm) implanted NV centres using an optimised overgrowth process. Furthermore, the charge state of ensembles and single NV centres was found to be shifted from NV0to NV−and stabilised in the negative charge state after overgrowth. The combination of low‐energy high‐resolution ion implantation and high‐purity chemical vapour deposition (CVD) overgrowth procedures opens the way towards the fabrication of scalable and efficient quantum devices based on single defects in diamond. Left: implanted pattern of very shallow NV centres (depth ∼2 nm) using a pierced AFM tip. Right: same pattern after CVD overgrowth of a 4 μm‐thick diamond layer.

Lately, fluorescence quenching microscopy (FQM) has been introduced as a new tool to visualize graphene-based sheets. Even though quenching of the emission from a dye molecule by fluorescence resonance energy transfer (FRET) to graphene happens on the nanometer scale, the resolution of FQM so far is still limited to several hundreds of nanometers due to the Abbe limit restricting the resolution of conventional light microscopy. In this work, we demonstrate an advancement of FQM by using a super-resolution imaging technique for detecting fluorescence of color centers used in FQM. The technique is similar to stimulated emission depletion microscopy (STED). The combined “FRET+STED” technique introduced here for the first time represents a substantial improvement to FQM since it exhibits in principle unlimited resolution while still using light in the visible spectral range. In the present case we demonstrate all-optical imaging of graphene with resolution below 30 nm. The performance of the technique in terms of imaging resolution and contrast is well described by a theoretical model taking into account the general distance dependence of the FRET process and the distance distribution of donor centers with respect to the flake. In addition, the change in lifetime for partially quenched emitters allows extracting the quenching distance from experimental data for the first time.

van Marum RJ, Meijer JH, Ribbe MW. The relationship between pressure ulcers and skin blood flow response after a local cold provocation. Arch Phys Med Rehabil 2002;83;40-3. Objective:To study the relationship between an impaired blood flow response after a local cold stimulus, testing nerve regulation of the local blood flow response, and an increased risk of developing pressure ulcers. Design:An observational, longitudinal, prospective study. Setting:Dutch nursing home. Patients:Eighty-two newly admitted somatic nursing home patients, age 60 years and older. Intervention:A local cold stimulus (17°C) applied to the trochanter major. Main Outcome Measures:On admission, blood flow response to a local cold stimulus. As the stimulus was withdrawn, the temperature measured at the skin increased asymptotically toward the final temperature, Tf. The velocity of this rise was characterized by the time constant, τ, of the process. On admission, and weekly during a 4-week follow-up period, the presence or absence of pressure ulcers was verified. Results:The blood flow response time correlated significantly with the risk of developing pressure ulcers. The patients who developed pressure ulcers during the follow-up period had a significantly longer response time than the patients who did not. Conclusions:Malfunction of the nervous regulatory mechanisms of the local blood flow is partially responsible for an increased susceptibility to pressure ulcer formation. © 2002 by the American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation

A combination of high resolution cathodoluminescence-spectroscopy (HRS-CL=high resolution spectroscopy of cathodoluminescence emission) with spatial resolving trace element analyses (PIXE=proton induced X-ray emission) is used to establish a method for the quantitative determination of the Mn-content of diagenetic and hydrothermal dolomites using the measurements of peak areas of Mn-activated CL emission bands. This method takes into account the overlap of the CL broad bands of Mn2+in the Mg- and the Ca-lattice-position of dolomite. There is a linear correlation between the peak areas and Mn concentration up to approx. 1000–1500ppm. Thus, CL spectroscopy allows a determination of Mn concentrations below the abilities of PIXE (10–15ppm) to less than 1ppm by extrapolation of this linear relation.

The mechanisms of suppression of fusarium wilt of carnation by two fluorescentPseudomonas strains were studied.

The carabid and spider faunas of a young polder, reclaimed from a tidal flat, was studied in two areas with pitfall traps. Data are presented on the soil and the vegetation.

Enprostil, a synthetic prostaglandin E2analog, has been shown to decrease gastric acid secretion and plasma gastrin levels during short-term treatment. However, effects of prolonged treatment with enprostil on these parameters in humans are unknown. We have studied the effects of 35 µg enprostil twice daily on 24-hour intragastric pH, basal gastrin, and meal-stimulated gastrin release in 10 healthy volunteers. Enprostil, 35 µg, was ingested twice daily for 4 weeks. Subjects were studied on day 0 (preentry) and days 1 and 29, when enprostil was taken 30 minutes before the first and third standard test meals at 9 AM and 5 PM. Enprostil significantly increased 24-hour median pH (p < 0.02) on day 1 but not on day 29. Enprostil had no significant effect on basal gastrin levels compared with placebo. However, on day 1, but not on day 29, postprandial gastrin levels were significantly lower compared with preentry (p < 0.05). On day 29 postprandial gastrin levels after the second standard test meal were significantly higher compared with preentry data (p < 0.05). In conclusion, 35 µg enprostil twice daily reduced gastric acidity and serum gastrin levels on the first day of treatment, but this effect attenuated and even transiently reversed during a 4-week treatment period.

The development and distribution of the nerves in the heart of the pig was studied macroscopically and by light microscopy. Hearts were collected from 86 fetuses between 31 and 114 days of gestation (term=114 days), from 12 neonatal pigs aged 9 and 20 days and from 6 adult sows of the Dutch Landrace breed. The effect of vagotomy produced by decapitation in utero at 40–43 days was studied in an additional 24 hearts from fetuses aged between 51 and 114 days of gestation. The amount of acetyl-thiocholine reactive fibres increases in the atria, A-V node and ventricles throughout gestation. At every age the amount of nervous tissue is highest in the A-V node and lowest in the ventricles. Hearts from decapitated fetuses have smaller amounts of nerve tissue than those from intact fetuses at every age studied. Ganglia are present in both intact and decapitated fetuses. Fluorescent cells containing catecholamines are observed in hearts from fetuses as young as 35 days gestation. Although fluorescent nerve fibres are rarely seen in hearts at 70 days gestation, more fibres are present near birth and thereafter there appears to be a considerable increase in the number of fibres and in the intensity with which they fluoresce.

Owing to its unique optical and spin properties, the nitrogen‐vacancy (NV) center holds the promise of a diamond‐based room‐temperature scalable quantum computer, but the numerous technical and physical issues are not yet overcome, especially the poor N to NV conversion. The NV and other color centers are, however, successfully used as multitasking quantum sensors, and open new routes in quantum sensing technologies. Most recently, several breakthroughs and demonstrations were achieved, shedding a new light on the feasibility of a NV‐based quantum computer. Herein, the recently developed method of charge‐assisted single defect engineering is reviewed. With a controlled charging of the involved species, it modifies the diffusion or kinetics of defect formation and acts as a catalyzer of the NV creation while hindering the formation of competing and perturbing defects such as divacancies or NVH. Very high NV creation yields up to 75% are obtained and the method is suitable to other impurity‐vacancy defects. Furthermore, it has positive consequences on the charge state stability and coherence time of the NV centers, which is as well discussed. Together with the possibility to nowadays deterministically implant single ions, this powerful method brings the scalability of NV qubits closer. The recently developed method of charge‐assisted single defect engineering is reviewed. Applying this method to color centers in diamond enables a strong enhancement of their creation while hindering formation of competing and perturbing defects. Furthermore, improved charge state stability and coherence times are obtained. This powerful method brings the full scalability of solid‐state qubits or quantum sensors closer.

Ion Channeling and Scattering A nanoaperture defined by drilling in a hollow pyramidal atomic force microscope (AFM) tip is used to produce precise nitrogen vacancy (NV) center nanostructures in diamond by low energy nitrogen implantation. Ion scattering and channeling are the most important limiting factors to achieve high lateral resolution. In article number 1900528by Nicole Raatz and co‐workers, both effects are studied using iradina, crystal‐trim and corresponding experiments.

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