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1.
Curr Alzheimer Res ; 2024 May 03.
Article in English | MEDLINE | ID: mdl-38706355

ABSTRACT

BACKGROUND: A poor prenatal environment adversely affects brain development. Studies investigating long-term consequences of prenatal exposure to the 1944-45 Dutch famine have shown that those exposed to famine in early gestation had poorer selective attention, smaller brain volumes, poorer brain perfusion, older appearing brains, and increased reporting of cognitive problems, all indicative of increased dementia risk. OBJECTIVE: In the current population-based study, we investigated whether dementia incidence up to age 75 was higher among individuals who had been prenatally exposed to famine. METHODS: We included men (n=6,714) and women (n=7,051) from the Nivel Primary Care Database who had been born in seven cities affected by the Dutch famine. We used Cox regression to compare dementia incidence among individuals exposed to famine during late (1,231), mid (1,083), or early gestation (601) with those unexposed (born before or conceived after the famine). RESULTS: We did not observe differences in dementia incidence for those exposed to famine in mid or early gestation compared to those unexposed. Men and women exposed to famine in late gestation had significantly lower dementia rates compared to unexposed individuals (HR 0.52 [95%CI 0.30-0.89]). Sex-specific analyses showed a lower dementia rate in women exposed to famine in late gestation (HR 0.39 [95%CI 0.17-0.86]) but not in men (HR 0.68 [95%CI 0.33-1.41]). CONCLUSION: Although prenatal exposure to the Dutch famine has previously been associated with measures of accelerated brain aging, the present population-based study did not show increased dementia incidence up to age 75 in those exposed to famine during gestation.

2.
Hum Factors ; : 187208241236395, 2024 Mar 06.
Article in English | MEDLINE | ID: mdl-38445657

ABSTRACT

OBJECTIVE: We examined whether active head aiming with a Helmet Mounted Display (HMD) can draw the pilot's attention away from a primary flight task. Furthermore, we examined whether visual clutter increases this effect. BACKGROUND: Head up display symbology can result in attentional tunneling, and clutter makes it difficult to identify objects. METHOD: Eighteen military pilots had to simultaneously perform an attitude control task while flying in clouds and a head aiming task in a fixed-base flight simulator. The former consisted of manual compensation for roll disturbances of the aircraft, while the latter consisted of keeping a moving visual target inside a small or large head-referenced circle. A "no head aiming" condition served as a baseline. Furthermore, all conditions were performed with or without visual clutter. RESULTS: Head aiming led to deterioration of the attitude control task performance and an increase of the amount of roll-reversal errors (RREs). This was even the case when head aiming required minimal effort. Head aiming accuracy was significantly lower when the roll disturbances in the attitude control task were large compared to when they were small. Visual clutter had no effect on both tasks. CONCLUSION: We suggest that active head aiming of HMD symbology can cause attentional tunneling, as expressed by an increased number of RREs and less accuracy on a simultaneously performed attitude control task. APPLICATION: This study improves our understanding in the perceptual and cognitive effects of (military) HMDs, and has implications for operational use and possibly (re)design of HMDs.

3.
Phys Rev Lett ; 132(10): 103401, 2024 Mar 08.
Article in English | MEDLINE | ID: mdl-38518353

ABSTRACT

The excitation spectrum of a cigar-shaped strongly dipolar quantum gas at the crossover from a Bose-Einstein condensate to a trapped macrodroplet is predicted to exhibit peculiar features-a strong upward shift of low momentum excitation energies together with a strong multiband response for high momenta. By performing Bragg spectroscopy over a wide range of momenta, we observe both key elements and also confirm the predicted stiffening of excitation modes when approaching the macrodroplet regime. Our measurements are in good agreement with numerical calculations taking into account finite size effects.

4.
Aerosp Med Hum Perform ; 95(2): 84-92, 2024 Feb 01.
Article in English | MEDLINE | ID: mdl-38263100

ABSTRACT

INTRODUCTION: The illusions of head motion induced by galvanic vestibular stimulation (GVS) can be used to compromise flight performance of pilots in fixed-base simulators. However, the stimuli used in the majority of studies fail to mimic disorientation in realistic flight because they are independent from the simulated aircraft motion. This study investigated the potential of bilateral-bipolar GVS coupled to aircraft roll in a fixed-base simulator to mimic vestibular spatial disorientation illusions, specifically the "post-roll illusion" observed during flight.METHODS: There were 14 nonpilot subjects exposed to roll stimuli in a flight simulator operating in a fixed-base mode. GVS was delivered via carbon rubber electrodes on the mastoid processes. The electrical stimulus was driven by the high-pass filtered aircraft roll rate to mimic the semicircular canals' physiological response. The post-roll test scenarios excluded outside visual cues or instruments and required subjects to actively maintain a constant bank angle after an abrupt stop following a passive prolonged roll maneuver. The anticipated outcome was an overshot in roll elicited by the GVS signal.RESULTS: The responses across subjects showed large variability, with less than a third aligning with the post-roll illusion. Subjective ratings suggest that the high-pass filtered GVS stimuli were mild and did not induce a clear sense of roll direction. However, uncontrolled head movements during stimulation might have obscured the intended effects of GVS-evoked illusory head movements.CONCLUSION: The mild and transient GVS stimuli used in this study, together with the uncontrolled head movements, did not convincingly mimic the post-roll illusion.Houben MMJ, Stuldreher IV, Forbes PA, Groen EL. Using galvanic vestibular stimulation to induce post-roll illusion in a fixed-base flight simulator. Aerosp Med Hum Perform. 2024; 95(2):84-92.


Subject(s)
Illusions , Humans , Aircraft , Confusion , Cues
5.
Aerosp Med Hum Perform ; 95(1): 16-24, 2024 Jan 01.
Article in English | MEDLINE | ID: mdl-38158569

ABSTRACT

BACKGROUND: In this study, we investigated the impact of a loss of horizon due to atmospheric conditions on flight performance and workload of helicopter pilots during a low-altitude, dynamic flight task in windy conditions at sea. We also examined the potential benefits of a helmet-mounted display (HMD) for this specific task.METHODS: In a fixed-based helicopter simulator, 16 military helicopter pilots were asked to follow a maneuvering go-fast vessel in a good visual environment (GVE) and in a degraded visual environment (DVE). DVE was simulated by fog, obscuring the horizon and reducing contrast. Both visual conditions were performed once with and once without an HMD, which was simulated by projecting head-slaved symbology in the outside visuals. Objective measures included flight performance, control inputs, gaze direction, and relative positioning. Subjective measures included self-ratings on performance, situation awareness, and workload.RESULTS: The results showed that in DVE the pilots perceived higher workload and were flying closer to the go-fast vessel than in GVE. Consequently, they responded with larger control inputs to maneuvers of the vessel. The availability of an HMD hardly improved flight performance but did allow the pilots to focus their attention more outside, significantly improving their situation awareness and reducing workload. These benefits were found in DVE as well as GVE conditions.DISCUSSION: DVE negatively affects workload and flight performance of helicopter pilots in a dynamic, low-altitude following task. An HMD can help improve situation awareness and lower the workload during such a task, irrespective of the visual conditions.Ledegang WD, van der Burg E, Valk PJL, Houben MMJ, Groen EL. Helicopter pilot performance and workload in a following task in a degraded visual environment. Aerosp Med Hum Perform. 2024; 95(1):16-24.


Subject(s)
Aerospace Medicine , Pilots , Humans , Workload , Aircraft , Awareness , Task Performance and Analysis
6.
Pneumonia (Nathan) ; 15(1): 13, 2023 Sep 05.
Article in English | MEDLINE | ID: mdl-37667350

ABSTRACT

BACKGROUND: Although the association between living in the vicinity of a goat farm and the occurrence of pneumonia is well-documented, it is unclear whether the higher risk of pneumonia in livestock dense areas is season-specific or not. This study explored the temporal variation of the association between exposure to goat farms and the occurrence of pneumonia. METHODS: A large population-based study was conducted in the Netherlands, based on electronic health records from 49 general practices, collected for a period of six consecutive years (2014-2019). Monthly incidence rates of pneumonia in a livestock dense area were compared with those of a control group (areas with low livestock density) both per individual year and cumulatively for the entire six-year period. Using individual estimates of livestock exposure, it was also examined whether incidence of pneumonia differed per month if someone lived within a certain radius from a goat farm, compared to residents who lived further away. RESULTS: Pneumonia was consistently more common in the livestock dense area throughout the year, compared to the control area. Analyses on the association between the individual livestock exposure estimates and monthly pneumonia incidence for the whole six-year period, yielded a generally higher risk for pneumonia among people living within 500 m from a goat farm, compared to those living further away. Significant associations were observed for March (IRR 1.68, 95% CI 1.02-2.78), August (IRR 2.67, 95% CI 1.45-4.90) and September (IRR 2.52, 95% CI 1.47-4.32). CONCLUSIONS: The increased occurrence of pneumonia in the vicinity of goat farms is not season-specific. Instead, pneumonia is more common in livestock dense areas throughout the year, including summer months.

7.
Arch Rehabil Res Clin Transl ; 5(1): 100253, 2023 Mar.
Article in English | MEDLINE | ID: mdl-36968164

ABSTRACT

Objective: To determine the proportion of patients who return to work after inpatient stroke rehabilitation and to identify demographic, clinical, and functional predictive factors for its success. Design: A retrospective follow-up study of patients with stroke who were premorbidly working and had completed inpatient rehabilitation in a large metropolitan hospital between January 2016 and December 2017. They underwent a telephone interview at 2 years post discharge. Setting: Inpatient rehabilitation and follow-up post discharge. Participants: A total of 314 patients with stroke (73.9% male) with mean age of 58.9 at time of stroke (N=314). Results: A total of 46% of 314 participants returned to work. In multivariable logistic regression analysis, viewing return to work as important (odds ratio [OR], 11.90; 95% confidence interval [CI], 5.15-27.52), absence of language impairment (OR, 9.39; 95% CI, 3.01-29.34), ambulation FIM≥5 (supervision to independence level) on discharge (OR, 4.93; 95% CI, 2.44-9.98), cognitive FIM on discharge ≥25 (OR, 2.77; 95% CI, 1.19-6.47), employment in premorbid office work (OR, 2.67; 95% CI, 1.26-5.64), and a lower Charlson Comorbidity Index (CCI) score at discharge (OR, 0.83; 95% CI, 0.68-1.00) were associated with successful return to work. Conclusions: Viewing return to work as important, absence of language impairments on discharge, discharge ambulation FIM≥5, discharge cognitive FIM≥25, employment in premorbid office work, and a lower discharge CCI score were positive predictors of successful return to work.

8.
Ergonomics ; 66(12): 2148-2164, 2023 Dec.
Article in English | MEDLINE | ID: mdl-36916391

ABSTRACT

This study investigates how cognitive performance is affected by the combination of two stressors that are operationally relevant for helicopter pilots: heat load and hypobaric hypoxia. Fifteen participants were exposed to (1) no stressors, (2) heat load, (3) hypobaric hypoxia, and (4) combined heat load and hypobaric hypoxia. Hypobaric hypoxia (13,000 ft) was achieved in a hypobaric chamber. Heat load was induced by increasing ambient temperature to ∼28 °C. Cognitive performance was measured using two multitasks, and a vigilance task. Subjective and physiological data (oxygen saturation, heart rate, core- and skin temperature) were also collected. Mainly heat load caused cognitive performance decline. This can be explained by high subjective heat load and increased skin temperature, which takes away cognitive resources from the tasks. Only the arithmetic subtask was sensitive to hypobaric hypoxia, whereby hypobaric hypoxia caused a further performance decline in addition to the decline caused by heat load.Practitioner summary: Little is known about how multiple environmental stressors interact. This study investigates the combined effects of heat load and hypobaric hypoxia on cognitive performance. An additive effect of heat load and hypobaric hypoxia was found on a arithmetic task, which may be attributed to independent underlying mechanisms.


Subject(s)
Cognitive Dysfunction , Hot Temperature , Humans , Hypoxia/psychology , Aircraft , Cognition
9.
J Acoust Soc Am ; 152(6): 3706, 2022 12.
Article in English | MEDLINE | ID: mdl-36586852

ABSTRACT

In a laboratory study, the indoor annoyance caused by the sound produced by aircraft during the takeoff on the runway is investigated. This aircraft sound is dominated by relatively high sound levels in the 16 and 31.5 Hz octave bands. Road-traffic and passenger railway sounds, which lack high sound levels in these octave bands, are included as references. The sounds are presented at indoor A-weighted equivalent levels of 32 and 42 dB. The participants are males and females between 20 and 40, or between 40 and 60 years of age. The indoor annoyance increased with sound level, but it was not affected by source type. Moreover, it was not or hardly affected by gender or age. With the dose expressed as A-weighted outdoor levels, the penalty for the aircraft sound and the bonus for the passenger railway sound at least qualitatively correspond to those obtained in pertinent previous studies. In the present study, such adjustments can be avoided by including the difference between the outdoor C-weighted and A-weighted levels as a second predictor, yielding an explained variance in the mean indoor annoyance ratings as high as 98%.


Subject(s)
Noise, Transportation , Male , Female , Humans , Noise, Transportation/adverse effects , Sound , Aircraft
10.
Mater Horiz ; 9(10): 2572-2580, 2022 10 03.
Article in English | MEDLINE | ID: mdl-35894556

ABSTRACT

Control over the assembly and morphology of nanoscale functional building blocks is of great importance to hybrid and porous nanomaterials. In this paper, by combining different types of spherical nanoparticles with different size ratios in a hierarchical assembly process which allows us to control the final structure of multi-component assemblies, we discuss self-assembly of an extensive range of supraparticles, labelled as AB particles, and an extension to novel ternary particles, labelled as ABC particles. For supraparticles, the organization of small nanoparticles is known to be inherently related to the size ratio of building blocks. Therefore, we studied the formation of supraparticles prepared by colloidal self-assembly using small silica nanoparticles (SiO2 NPs) attached on the surface of large polystyrene latex nanoparticles (PSL NPs) with a wide size ratio range for complete and partial coverage, by controlling the electrostatic interactions between the organic and inorganic nanoparticles and their concentrations. In this way hierarchically ordered, stable supraparticles, either fully covered or partially covered, were realized. The partially covered, stable AB supraparticles offer the option to create ABC supraparticles of which the fully covered shell contains two different types of nanoparticles. This has been experimentally confirmed using iron oxide (Fe3O4) nanoparticles together with silica nanoparticles as shell particles on polystyrene core particles. Cryo-electron tomography was used to visualize the AB binary and ABC ternary supraparticles and to determine the three-dimensional structural characteristics of supraparticles formed under different conditions.


Subject(s)
Nanoparticles , Nanostructures , Nanoparticles/chemistry , Polystyrenes , Porosity , Silicon Dioxide/chemistry
11.
CrystEngComm ; 24(6): 1211-1217, 2022 Feb 07.
Article in English | MEDLINE | ID: mdl-35221796

ABSTRACT

The mineralization of collagen in vitro has been extensively investigated for hydroxyapatite, silica, calcium carbonate and lepidocrocite (γ-FeOOH). Henceforth, it is interesting to investigate whether collagen also could serve as a generic mineralization template for other minerals, like magnetite. To this end, and inspired by the partial oxidation approach, first a ferrous hydroxide (Fe(OH)2) intermediate is synthesized via the titration of base to a solution of Fe2+. Subsequently, the Fe(OH)2 is mixed with collagen fibrils and poly(aspartic acid) is added to promote the formation of intrafibrillar crystals. Platelet-shaped lepidocrocite crystals being present throughout the entire thickness of the collagen fibrils can be realized, as was confirmed with electron tomography. The formation of lepidocrocite, which is an Fe3+ compound, is hypothesized to be induced via oxidation of the Fe2+ species and, therefore, the oxygen concentration during titration, TEM sample preparation and drying of TEM samples are investigated. Although the reaction is sensitive to small changes in experimental conditions, highly mineralized collagen fibers can be realized.

12.
J Vestib Res ; 32(4): 317-324, 2022.
Article in English | MEDLINE | ID: mdl-34924407

ABSTRACT

BACKGROUND: The vestibular Coriolis illusion is a disorienting sensation that results from a transient head rotation about one axis during sustained body rotation about another axis. Although often used in spatial disorientation training for pilots and laboratory studies on motion sickness, little is known about the minimum required rotation rate to produce the illusion. OBJECTIVE: This study determined the perception threshold associated with the Coriolis illusion. METHODS: Nineteen participants performed a standardized pitching head movement during continuous whole-body yaw rotation at rates varying between 5 to 50 deg/s. The participants reported their motion sensation in relation to three hypothesized perception thresholds: 1) a sense of undefined self-motion, 2) a sense of rotation, and 3) a sense of rotation and its direction (i.e., the factual Coriolis illusion). The corresponding thresholds were estimated from curves fitted by a generalized linear model. RESULTS: On average threshold 1 was significantly lower (8 deg/s) than thresholds 2 and 3. The latter thresholds did not differ from each other and their pooled value was 10 deg/s. CONCLUSIONS: The Coriolis illusion is perceived at yaw rates exceeding 10 deg/s using a pitching head movement with 40 deg amplitude and 55 deg/s peak velocity. Model analysis shows that this corresponds to an internal rotation vector of 6 deg/s. With this vector the Coriolis perception threshold can be predicted for any other head movement.


Subject(s)
Illusions , Motion Perception , Motion Sickness , Vestibule, Labyrinth , Head Movements , Humans , Sensation
13.
ACS Biomater Sci Eng ; 7(7): 3123-3131, 2021 07 12.
Article in English | MEDLINE | ID: mdl-34161069

ABSTRACT

The mineralization of collagen via synthetic procedures has been extensively investigated for hydroxyapatite as well as for silica and calcium carbonate. From a fundamental point of view, it is interesting to investigate whether collagen could serve as a generic mineralization template for other minerals, like iron oxides. Here, bio-inspired coprecipitation reaction, generally leading to the formation of magnetite, is used to mineralize collagen with iron hydroxides. Platelet-shaped green rust crystals form outside the collagen matrix, while inside the collagen, nanoparticles with a size of 2.6 nm are formed, which are hypothesized to be iron (III) hydroxide. Mineralization with nanoparticles inside the collagen solely occurs in the presence of poly(aspartic acid) (pAsp). In the absence of pAsp, magnetite particles are formed around the collagen. Time-resolved cryo-TEM shows that during the coprecipitation reaction, initially a beam-sensitive phase is formed, possibly an Fe3+-pAsp complex. This beam-sensitive phase transforms into nanoparticles. In a later stage, sheet-like crystals are also found. After 48 h of mineralization, ordering of the nanoparticles around one of the collagen sub-bands (the a-band) is observed. This is very similar to the collagen-hydroxyapatite system, indicating that mineralization with iron hydroxides inside collagen is possible and proceeds via a similar mechanism as hydroxyapatite mineralization.


Subject(s)
Hydroxides , Iron , Collagen , Durapatite , Ferrosoferric Oxide
14.
CrystEngComm ; 23(18): 3340-3348, 2021 Mar 24.
Article in English | MEDLINE | ID: mdl-34093087

ABSTRACT

Hexamethylenetetramine (HMTA) is commonly used as a base releasing agent for the synthesis of ZnO under mild aqueous conditions. HMTA hydrolysis leads to gradual formation of a base during the reaction. Use of HMTA, however, does have limitations: HMTA hydrolysis yields both formaldehyde and ammonia, it provides no direct control over the ammonia addition rate or the total amount of ammonia added during the reaction, it results in a limited applicable pH range and it dictates the accessible reaction temperatures. To overcome these restrictions, this work presents a direct base titration strategy for ZnO synthesis in which a continuous base addition rate is maintained. Using this highly flexible strategy, wurtzite ZnO can be synthesized at a pH >5.5 using either KOH or ammonia as a base source at various addition rates and reaction pH values. In situ pH measurements suggest a similar reaction mechanism to HMTA-based synthesis, independent of the varied conditions. The type and concentration of the base used for titration affect the reaction product, with ammonia showing evidence of capping behaviour. Optimizing this strategy, we are able to influence and direct the crystal shape and significantly increase the product yield to 74% compared to the ∼13% obtained by the reference HMTA reaction.

15.
J Vestib Res ; 31(5): 345-352, 2021.
Article in English | MEDLINE | ID: mdl-33867364

ABSTRACT

BACKGROUND: During large angles of self-tilt in the roll plane on Earth, measurements of the subjective visual vertical (SVV) in the dark show a bias towards the longitudinal body axis, reflecting a systematic underestimation of self-tilt. OBJECTIVE: This study tested the hypothesis that self-tilt is underestimated in partial gravity conditions, and more so at lower gravity levels. METHODS: The SVV was measured in parabolic flight at three partial gravity levels: 0.25, 0.50, and 0.75 g. Self-tilt was varied amongst 0, 15, 30, and 45 deg, using a tiltable seat. The participants indicated their SVV by setting a linear array of dots projected inside a head mounted display to the perceived vertical. The angles of participants' body and head roll tilt relative to the gravito-inertial vertical were measured by two separate inertial measurement units. RESULTS: Data on six participants were collected. Per G-level, a regression analysis was performed with SVV setting as dependent variable and head tilt as independent variable. The latter was used instead of chair tilt, because not all the participants' heads were aligned with their bodies. The estimated regression slopes significantly decreased with smaller G-levels, reflecting an increased bias of the SVV towards the longitudinal body axis. On average, the regression slopes were 0.95 (±0.38) at 0.75 g; 0.84 (±0.22) at 0.5 g; and 0.63 (±0.33) at 0.25 g. CONCLUSIONS: The results of this study show that reduced gravity conditions lead to increased underestimation of roll self-tilt.


Subject(s)
Hypogravity , Orientation , Gravitation , Gravity Sensing , Humans , Space Perception
16.
Health Sci Rep ; 4(2): e256, 2021 Jun.
Article in English | MEDLINE | ID: mdl-33778166

ABSTRACT

BACKGROUND AND AIMS: Since cardiometabolic diseases (CMD) are a frequent cause of death worldwide, preventive strategies are needed. Recruiting adults for a health check could facilitate the identification of individuals at risk for CMD. For successful results, participation is crucial. We aimed to identify factors related to unwillingness to participate in CMD health checks. METHODS: We performed a cross-sectional study in the Czech Republic, Denmark, Greece, the Netherlands, and Sweden. A questionnaire was distributed among persons without known CMD consulting general practice between January and July 2017 within the framework of the SPIMEU study. RESULTS: In total, 1354 persons responded. Nine percent was unwilling to participate in a CMD health check. Male gender, smoking, higher self-rated health, never been invited before, and not willing to pay were related to unwillingness to participate. The most mentioned reason for unwillingness to participate was "I think that I am healthy" (57%). Among the respondents who were willing to participate, 94% preferred an invitation by the general practitioner and 66% was willing to pay. CONCLUSION: A minority of the respondents was unwilling to participate in a CMD health check with consistent results within the five countries. This provides a promising starting point to increase participation in CMD health checks in primary care.

17.
BMC Med ; 19(1): 57, 2021 03 11.
Article in English | MEDLINE | ID: mdl-33691699

ABSTRACT

BACKGROUND: Cardiometabolic diseases (CMD) are the major cause of death worldwide and are associated with a lower quality of life and high healthcare costs. To prevent a further rise in CMD and related healthcare costs, early detection and adequate management of individuals at risk could be an effective preventive strategy. The objective of this study was to determine long-term cost-effectiveness of stepwise CMD risk assessment followed by individualized treatment if indicated compared to care as usual. A computer-based simulation model was used to project long-term health benefits and cost-effectiveness, assuming the prevention program was implemented in Dutch primary care. METHODS: A randomized controlled trial in a primary care setting in which 1934 participants aged 45-70 years without recorded CMD or CMD risk factors participated. The intervention group was invited for stepwise CMD risk assessment through a risk score (step 1), additional risk assessment at the practice in case of increased risk (step 2) and individualized follow-up treatment if indicated (step 3). The control group was not invited for risk assessment, but completed a health questionnaire. Results of the effectiveness analysis on systolic blood pressure (- 2.26 mmHg; 95% CI - 4.01: - 0.51) and total cholesterol (- 0.15 mmol/l; 95% CI - 0.23: - 0.07) were used in this analysis. Outcome measures were the costs and benefits after 1-year follow-up and long-term (60 years) cost-effectiveness of stepwise CMD risk assessment compared to no assessment. A computer-based simulation model was used that included data on disability weights associated with age and disease outcomes related to CMD. Analyses were performed taking a healthcare perspective. RESULTS: After 1 year, the average costs in the intervention group were 260 Euro higher than in the control group and differences were mainly driven by healthcare costs. No meaningful change was found in EQ 5D-based quality of life between the intervention and control groups after 1-year follow-up (- 0.0154; 95% CI - 0.029: 0.004). After 60 years, cumulative costs of the intervention were 41.4 million Euro and 135 quality-adjusted life years (QALY) were gained. Despite improvements in blood pressure and cholesterol, the intervention was not cost-effective (ICER of 306,000 Euro/QALY after 60 years). Scenario analyses did not allow for a change in conclusions with regard to cost-effectiveness of the intervention. CONCLUSIONS: Implementation of this primary care-based CMD prevention program is not cost-effective in the long term. Implementation of this program in primary care cannot be recommended. TRIAL REGISTRATION: Dutch Trial Register NTR4277 , registered on 26 November 2013.


Subject(s)
Cost-Benefit Analysis/methods , Metabolic Syndrome/economics , Metabolic Syndrome/prevention & control , Aged , Female , Humans , Male , Middle Aged
18.
Open Heart ; 8(1)2021 01.
Article in English | MEDLINE | ID: mdl-33462107

ABSTRACT

AIMS: To validate a multivariable risk prediction model (Cohorts for Heart and Aging Research in Genomic Epidemiology model for atrial fibrillation (CHARGE-AF)) for 5-year risk of atrial fibrillation (AF) in routinely collected primary care data and to assess CHARGE-AF's potential for automated, low-cost selection of patients at high risk for AF based on routine primary care data. METHODS: We included patients aged ≥40 years, free of AF and with complete CHARGE-AF variables at baseline, 1 January 2014, in a representative, nationwide routine primary care database in the Netherlands (Nivel-PCD). We validated CHARGE-AF for 5-year observed AF incidence using the C-statistic for discrimination, and calibration plot and stratified Kaplan-Meier plot for calibration. We compared CHARGE-AF with other predictors and assessed implications of using different CHARGE-AF cut-offs to select high-risk patients. RESULTS: Among 111 475 patients free of AF and with complete CHARGE-AF variables at baseline (17.2% of all patients aged ≥40 years and free of AF), mean age was 65.5 years, and 53% were female. Complete CHARGE-AF cases were older and had higher AF incidence and cardiovascular comorbidity rate than incomplete cases. There were 5264 (4.7%) new AF cases during 5-year follow-up among complete cases. CHARGE-AF's C-statistic for new AF was 0.74 (95% CI 0.73 to 0.74). The calibration plot showed slight risk underestimation in low-risk deciles and overestimation of absolute AF risk in those with highest predicted risk. The Kaplan-Meier plot with categories <2.5%, 2.5%-5% and >5% predicted 5-year risk was highly accurate. CHARGE-AF outperformed CHA2DS2-VASc (Cardiac failure or dysfunction, Hypertension, Age >=75 [Doubled], Diabetes, Stroke [Doubled]-Vascular disease, Age 65-74, and Sex category [Female]) and age alone as predictors for AF. Dichotomisation at cut-offs of 2.5%, 5% and 10% baseline CHARGE-AF risk all showed merits for patient selection in AF screening efforts. CONCLUSION: In patients with complete baseline CHARGE-AF data through routine Dutch primary care, CHARGE-AF accurately assessed AF risk among older primary care patients, outperformed both CHA2DS2-VASc and age alone as predictors for AF and showed potential for automated, low-cost patient selection in AF screening.


Subject(s)
Atrial Fibrillation/diagnosis , Electronic Health Records/statistics & numerical data , Patient Selection , Risk Assessment/methods , Stroke/prevention & control , Aged , Atrial Fibrillation/complications , Atrial Fibrillation/epidemiology , Data Management , Female , Follow-Up Studies , Humans , Male , Morbidity/trends , Netherlands/epidemiology , Retrospective Studies , Stroke/epidemiology , Stroke/etiology , Time Factors
19.
Nat Mater ; 20(4): 541-547, 2021 04.
Article in English | MEDLINE | ID: mdl-33510444

ABSTRACT

Periodic nano- or microscale structures are used to control light, energy and mass transportation. Colloidal organization is the most versatile method used to control nano- and microscale order, and employs either the enthalpy-driven self-assembly of particles at a low concentration or the entropy-driven packing of particles at a high concentration. Nonetheless, it cannot yet provide the spontaneous three-dimensional organization of multicomponent particles at a high concentration. Here we combined these two concepts into a single strategy to achieve hierarchical multicomponent materials. We tuned the electrostatic attraction between polymer and silica nanoparticles to create dynamic supracolloids whose components, on drying, reorganize by entropy into three-dimensional structured materials. Cryogenic electron tomography reveals the kinetic pathways, whereas Monte Carlo simulations combined with a kinetic model provide design rules to form the supracolloids and control the kinetic pathways. This approach may be useful to fabricate hierarchical hybrid materials for distinct technological applications.

20.
ACS Nano ; 14(5): 5874-5886, 2020 05 26.
Article in English | MEDLINE | ID: mdl-32348119

ABSTRACT

The functionalization of gold nanoparticles (GNPs) with peptidic moieties can prevent their aggregation and facilitate their use for applications both in vitro and in vivo. To date, no peptide-based coating has been shown to stabilize GNPs larger than 30 nm in diameter; such particles are of interest for applications including vaccine development, drug delivery, and sensing. Here, GNPs with diameters of 20, 40, and 100 nm are functionalized with peptide amphiphiles. Using a combination of transmission electron microscopy, UV-vis spectroscopy, and dynamic light scattering, we show that GNPs up to 100 nm in size can be stabilized by these molecules. Moreover, we demonstrate that these peptide amphiphiles form curvature-dependent, ordered structures on the surface of the GNPs and that the GNPs remain disperse at high-salt concentrations and in the presence of competing thiol-containing molecules. These results represent the development of a peptide amphiphile-based coating system for GNPs which has the potential to be beneficial for a wide range of biological applications, in addition to image enhancement and catalysis.


Subject(s)
Gold , Metal Nanoparticles , Dynamic Light Scattering , Microscopy, Electron, Transmission , Peptides
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