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Schools have been recognised as a potential setting for improving young peoples’ food and beverage choices; however, many schools fail to adhere to healthy food and beverage policy standards. The current study aimed to explore the enablers and barriers to effective implementation of and compliance with school-based food and beverage policies.
Systematic review and meta-synthesis. Eight electronic databases were searched for articles in June 2019. Studies were eligible for inclusion if they reported on implementation and/or compliance of school-based food and/or beverage policies with outcomes relating to enablers and/or barriers. This review had no restrictions on study design, year of publication or language. Seventy-two full-text articles were assessed for eligibility, of which twenty-eight were included in this review.
Studies conducted globally that focused on schools.
School-based healthy food and beverage policies.
Financial (cost of policy-compliant foods, decreased profit and revenue), physical (availability of policy-compliant foods, close geographical proximity to unhealthy food outlets) and social (poor knowledge, understanding, and negative stakeholders’ attitudes towards policy) factors were the most frequently reported barriers for policy implementation. Sufficient funding, effective policy communication and management, and positive stakeholders’ attitudes were the most frequently reported enablers for policy implementation.
There is a need for better communication strategies, financial and social support prior to school-based food policy implementation. Findings of this review contribute to a thorough understanding of factors that underpin best practice recommendations for the implementation of school-based food policy, and inform those responsible for improving public health nutrition.
Alcohol withdrawal is a clinically and etiologically heterogeneous syndrome caused by a complex interaction of environmental (e.g., amount of ethanol) and genetic factors. Multiple genes are considered to be involved in various components of the syndrome, each of them contributing only modestly to withdrawal vulnerability. Association studies using candidate genes of the dopamine, serotonin, gabaergic and opioidergic systems are reviewed and methodological limitations are discussed.
Within the vigilance regulation model the hyperactivity and sensation seeking observed in overtired children, ADHD and mania are interpreted as an autoregulatory attempt to stabilize vigilance (central nervous arousal) by increasing external stimulation. Correspondingly the withdrawal and sensation avoidance in major depression is interpreted as a reaction to a state of tonically high vigilance (1, 2). Using an EEG-based algorithm to classify automatically short EEG-segments into different vigilance stages as observed during the transition from active wakefulness to drowsiness and sleep onset (VIGALL), both patients with ADHD and mania show an unstable vigilance regulation with rapid drops to lower vigilance stages under quiet rest. The contrary was found in unmedicated patients with major depression (2). Studies will be presented supporting the validity of VIGALL (simulataneous EEG-fMRI and EEG/FDG-PET studies, as well as the neurophysiological, clinical and predictive validity of the vigilance regulation model of affective disorders. Among the far reaching consequences of the vigilance model is the question whether psychostimulants have similar beneficial effects in mania as observed in ADHD (3), an aspect which is presently studied in an international, randomized controlled trial (4).
Minor depression is diagnosed when a patient suffers from two to four depressive symptoms for at least two weeks. Though minor depression is a widespread phenomenon, its pathophysiology has hardly been studied. To get a first insight into the pathophysiological mechanisms underlying this disorder we assessed serum levels of biomarkers for plasticity, glial and neuronal function: brain-derived neurotrophic factor (BDNF), S100B and neuron specific enolase (NSE). Twenty-seven subjects with minor depressive episode and 82 healthy subjects over 60 years of age were selected from the database of the Leipzig population-based study of civilization diseases (LIFE). Serum levels of BDNF, S100B and NSE were compared between groups, and correlated with age, body-mass index, and degree of white matter hyperintensities (score on Fazekas scale). S100B was significantly increased in males with minor depression in comparison to healthy males, whereas other biomarkers did not differ between groups (P = 0.10–0.66). NSE correlated with Fazekas score in patients with minor depression (rs = 0.436, P = 0.048) and in the whole sample (rs = 0.252, P = 0.019). S100B correlated with body mass index (rs = 0.246, P = 0.031) and with age in healthy subjects (rs = 0.345, P = 0.002). Increased S100B in males with minor depression, without alterations in BDNF and NSE, supports the glial hypothesis of depression. Correlation between white matter hyperintensities and NSE underscores the vascular hypothesis of late life depression.
Disclosure of interest
The authors have not supplied their declaration of competing interest.
To identify differences in dietary quality, dietary greenhouse gas (GHG) emissions and food consumption over 20 years in a Dutch cohort.
Participants (n 8932) filled out an FFQ in 1993–1997 and in 2015. The Dutch Healthy Diet index 2015 (DHD15-index) score, GHG emissions and consumption of food groups (g/4184 kJ (1000 kcal)) were compared between the time points with paired t tests.
European Prospective Investigation into Cancer and Nutrition – Netherlands (EPIC-NL) cohort, aged 18–65 years at baseline.
Total energy intake decreased by –678 (95 % CI –4908, 3377) kJ/d (–162 (95 % CI –1173, 807) kcal/d) for men and –372 (95 % CI –3820, 3130) kJ/d (–89 (95 % CI –913, 748) kcal/d) for women. DHD15-index scores increased by 11 % (from 64·8 to 71·9 points) and 13 % (from 65·2 to 73·6 points) in men and women, respectively (P < 0·0001), mainly due to an increased (shell)fish and nuts/seeds/nut paste consumption. After energy intake adjustment, dietary-related GHG emissions increased by 5 % in men (2·48–2·61 kg CO2-eq/4184 kJ (1000 kcal), P < 0·0001) and were similar in women (0·4 %, 2·70–2·71 kg CO2-eq/4184 kJ (1000 kcal), P = 0·3930) due to the increased consumption of (shell)fish, nuts/seeds/nut paste, poultry and higher GHG-intensive red meats such as beef.
This Dutch cohort analyses showed more healthy diets without mitigated GHG emissions over a 20-year period, at similar energy intakes. Higher consumption of (shell)fish and poultry was not yet at the expense of red and processed meat. Lower consumption of animal-based foods is needed to achieve healthier as well as environmentally friendly diets.
The humble pendulum is often invoked as the archetype of a simple, gravity driven, oscillator. Under ideal circumstances, the oscillation frequency of the pendulum is independent of its mass and swing amplitude. However, in most real-world situations, the dynamics of pendulums is not quite so simple, particularly with additional interactions between the pendulum and a surrounding fluid. Here we extend the realm of pendulum studies to include large amplitude oscillations of heavy and buoyant pendulums in a fluid. We performed experiments with massive and hollow cylindrical pendulums in water, and constructed a simple model that takes the buoyancy, added mass, fluid (nonlinear) drag and bearing friction into account. To first order, the model predicts the oscillation frequencies, peak decelerations and damping rate well. An interesting effect of the nonlinear drag captured well by the model is that, for heavy pendulums, the damping time shows a non-monotonic dependence on pendulum mass, reaching a minimum when the pendulum mass density is nearly twice that of the fluid. Small deviations from the model’s predictions are seen, particularly in the second and subsequent maxima of oscillations. Using time-resolved particle image velocimetry (TR-PIV), we reveal that these deviations likely arise due to the disturbed flow created by the pendulum at earlier times. The mean wake velocity obtained from PIV is used to model an extra drag term due to incoming wake flow. The revised model significantly improves the predictions for the second and subsequent oscillations.
We present deep low radio frequency (230-470 MHz) observations from the Karl G. Jansky Very Large Array of the Perseus cluster, probing the non-thermal emission from the old particle population of the AGN outflows. Our observations of this nearby relaxed cool core cluster have revealed a multitude of new structures associated with the mini-halo, extending to hundreds of kpc in size. Its irregular morphology seems to have been influenced both by the AGN activity and by the sloshing motion of the cluster’ gas. In addition, it has a filamentary structure similar to that seen in radio relics found in merging clusters. These results illustrate the high-quality images that can be obtained with the new JVLA at low radio-frequencies.
The use of FDA approved medications for Alzheimer's disease [AD; FDAAMAD; (cholinesterase inhibitors and N-methyl-D-aspartate receptor antagonists)] has been associated with symptomatic benefit with a reduction in formal (paid services) and total costs of care (formal and informal costs). We examined the use of these medications and their association with informal costs in persons with dementia.
Two hundred eighty participants (53% female, 72% AD) from the longitudinal, population-based Dementia Progression Study in Cache County, Utah (USA) were followed up to ten years. Mean (SD) age at baseline was 85.6 (5.5) years. Informal costs (expressed in 2015 dollars) were calculated using the replacement cost method (hours of care multiplied by the median wage in Utah in the visit year) and adjusted for inflation using the Medical Consumer Price Index. Generalized Estimating Equations with a gamma log-link function were used to examine the longitudinal association between use of FDAAMAD and informal costs.
The daily informal cost for each participant at baseline ranged from $0 to $318.12, with the sample median of $9.40. Within the entire sample, use of FDAAMAD was not significantly associated with informal costs (expβ = 0.73, p = 0.060). In analyses restricted to participants with mild dementia at baseline (N = 222), use of FDAAMAD was associated with 32% lower costs (expβ = 0.68, p = 0.038).
Use of FDAAMAD was associated with lower informal care costs in those with mild dementia only.
The number of people entering specialist drug treatment for cannabis problems has increased considerably in recent years. The reasons for this are unclear, but rising cannabis potency could be a contributing factor.
Cannabis potency data were obtained from an ongoing monitoring programme in the Netherlands. We analysed concentrations of δ-9-tetrahydrocannabinol (THC) from the most popular variety of domestic herbal cannabis sold in each retail outlet (2000–2015). Mixed effects linear regression models examined time-dependent associations between THC and first-time cannabis admissions to specialist drug treatment. Candidate time lags were 0–10 years, based on normative European drug treatment data.
THC increased from a mean (95% CI) of 8.62 (7.97–9.27) to 20.38 (19.09–21.67) from 2000 to 2004 and then decreased to 15.31 (14.24–16.38) in 2015. First-time cannabis admissions (per 100 000 inhabitants) rose from 7.08 to 26.36 from 2000 to 2010, and then decreased to 19.82 in 2015. THC was positively associated with treatment entry at lags of 0–9 years, with the strongest association at 5 years, b = 0.370 (0.317–0.424), p < 0.0001. After adjusting for age, sex and non-cannabis drug treatment admissions, these positive associations were attenuated but remained statistically significant at lags of 5–7 years and were again strongest at 5 years, b = 0.082 (0.052–0.111), p < 0.0001.
In this 16-year observational study, we found positive time-dependent associations between changes in cannabis potency and first-time cannabis admissions to drug treatment. These associations are biologically plausible, but their strength after adjustment suggests that other factors are also important.
Guidelines for a healthy diet aim to decrease the risk of chronic diseases. It is unclear as to what extent a healthy diet is also an environmentally friendly diet. In the Dutch sub-cohort of the European Prospective Investigation into Cancer and Nutrition, the diet was assessed with a 178-item FFQ of 40 011 participants aged 20–70 years between 1993 and 1997. The WHO’s Healthy Diet Indicator (HDI), the Dietary Approaches to Stop Hypertension (DASH) score and the Dutch Healthy Diet index 2015 (DHD15-index) were investigated in relation to greenhouse gas (GHG) emissions, land use and all-cause mortality risk. GHG emissions were associated with HDI scores (−3·7 % per sd increase (95 % CI −3·4, −4·0) for men and −1·9 % (95 % CI −0·4, −3·4) for women), with DASH scores in women only (1·1 % per sd increase, 95 % CI 0·9, 1·3) and with DHD15-index scores (−2·5 % per sd increase (95 % CI −2·2, −2·8) for men and −2·0 % (95 % CI −1·9, −2·2) for women). For all indices, higher scores were associated with less land use (ranging from −1·3 to −3·1 %). Mortality risk decreased with increasing scores for all indices. Per sd increase of the indices, hazard ratios for mortality ranged from 0·88 (95 % CI 0·82, 0·95) to 0·96 (95 % CI 0·92, 0·99). Our results showed that adhering to the WHO and Dutch dietary guidelines will lower the risk of all-cause mortality and moderately lower the environmental impact. The DASH diet was associated with lower mortality and land use, but because of high dairy product consumption in the Netherlands it was also associated with higher GHG emissions.
Wolf-Rayet (WR) stars are the most advanced stage in the evolution of the most massive stars. The strong feedback provided by these objects and their subsequent supernova (SN) explosions are decisive for a variety of astrophysical topics such as the cosmic matter cycle. Consequently, understanding the properties of WR stars and their evolution is indispensable. A crucial but still not well known quantity determining the evolution of WR stars is their mass-loss rate. Since the mass loss is predicted to increase with metallicity, the feedback provided by these objects and their spectral appearance are expected to be a function of the metal content of their host galaxy. This has severe implications for the role of massive stars in general and the exploration of low metallicity environments in particular. Hitherto, the metallicity dependence of WR star winds was not well studied. In this contribution, we review the results from our comprehensive spectral analyses of WR stars in environments of different metallicities, ranging from slightly super-solar to SMC-like metallicities. Based on these studies, we derived empirical relations for the dependence of the WN mass-loss rates on the metallicity and iron abundance, respectively.
Some strategies in tissue engineering and regenerative medicine (TERM) rely on the use of an appropriate biomaterial to guide and foster tissue repair and regeneration. Collagen-based materials are perhaps the most widely investigated of these biomaterials because collagen is the primary structural protein responsible for tissue integrity in most tissues . Collagen gels offer several advantages as a scaffolding material, including the ability to deliver a homogeneous distribution of entrapped cells into a specific geometry and excellent biocompatibility and transport properties . However, collagen does have some disadvantages, including suppression of cell proliferation and protein synthesis [3, 4], issues that can limit the quality of the engineered tissue produced.
An alternative biopolymer that shares similar properties to collagen is fibrin. Fibrin is a natural biopolymer involved in the wound-healing process, and it forms the provisional matrix of a clot. It rapidly polymerizes to form a biocompatible and biodegradable fibrous scaffold that promotes cell proliferation and ECM synthesis. Another attractive property of fibrin is that its precursor (fibrinogen) can be extracted from the patient’s blood, making it an autologous material. In this chapter we will review the properties of fibrin and fibrin-based engineered tissues and how these materials are being incorporated into TERM technologies.
The semiconductor cuprous oxide crystallizes in a simple cubic structure and reveals outstanding characteristics: Independent of the method and conditions of the synthesis of crystalline Cu2O its Raman spectra are dominated by infrared active, silent, and defect modes rather than by Raman allowed phonon modes only. A detailed group theoretical analysis demonstrates that point defects reduce the local symmetry, lift the Raman selection rules, and thus diminish the distinction between Raman allowed and Raman forbidden lattice vibrations. Of all intrinsic defects only the presence of the copper vacancy in the so called split configuration introduces possible Raman activity for all Cu2O extended phonon modes observed in experiment.
Analysis of the Dutch national invasive pneumococcal disease (IPD) surveillance data by sex reveals an increase in the incidence of serotype-1 disease in young female adults in The Netherlands after the introduction of the 7-valent pneumococcal conjugate vaccine (PCV7) in the national immunization schedule. This has led to an overall increase in IPD in women aged 20–45 years, which was not observed in men of the same age. No other differences in serotype shifts possibly induced by the introduction of PCV7 were observed between the sexes in this age group. Serotype 1 is a naturally fluctuating serotype in Europe and it has been associated with disease in young healthy adults before. It remains uncertain whether or not there is an association between the observed increase in serotype-1 disease in young female adults and the implementation of PCV7 in The Netherlands.