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Developmental origins of health and disease research have cemented relationships between the early-life environment and later risk of non-communicable diseases (NCDs). However, there is limited translation of this knowledge in developing-economy nations, such as the Cook Islands, that carry exceptionally high NCD burdens. Considering the evidence, Cook Islands leaders identified a need for increased community awareness of the importance of early-life nutrition. Using a community-based participatory research approach, this study aimed to engage Cook Islands community representatives in the co-construction of a contextually relevant early-life nutrition resource. A booklet distributed to mothers in Australia and New Zealand was used as a starting point. Ten semi-structured focus groups (n = 60) explored views regarding the existing resource and options for contextual adaptation. Three core themes were identified: knowledge of the importance of early-life nutrition, recognition of the need for an early-life nutrition resource and the importance of resources being context specific. A draft booklet was created based on these discussions. Participants were invited to give feedback via a second round of focus groups. This confirmed that the voice of the community was represented in the draft booklet. Suggestions for additional material not included in the original resource were also identified. We report on the process and outcomes of the co-construction with community representatives of a resource that has the potential to be used to stimulate community-level discussion about the importance of early-life nutrition. It is crucial that communities have an active voice in research and in making decisions about interventions for their population.
The effect of methylphenidate (MPH) on inhibitory control as assessed by the stop task in children with attention-deficit/hyperactivity disorder (ADHD) could be influenced by task difficulty and may be mediated by attention.
Subjects and methods
Fifteen children with ADHD performed the stop and the change task after placebo, 0.5 and 1.0 mg/kg MPH in a within-subject design.
Linear-trend analysis showed a similar effect of MPH in both tasks and a stronger effect for inhibitory control than for attention. Furthermore, a correlation was found between blood serum metabolites of norepinephrine and dopamine for attentional measures and inhibitory control measures, respectively.
Discussion and conclusion
In children with ADHD MPH could act primarily on inhibitory control, and is not influenced by task difficulty. Also, attention and inhibitory control could have differential pharmacological profiles.
Although no pharmacological treatment has proved to be highly effective for reducing cocaine dependence, several medications have been tested over the last decade and have shown promising efficacy. Modafinil (Provigil), known as a treatment for day time sleepiness, and Topiramate (Topamax), an anti-epileptic medication also prescribed for migraine, have been shown to be effective in controlled clinical trials. We have recently started a major study utilizing Positron Emission Tomography (PET) brain imaging to monitor the progress of pharmacotherapy with modafinil or topiramate in cocaine-dependent and methadone-maintained cocaine-dependent patients. Patients will be assessed before treatment, and again after 4 weeks of pharmacotherapy. The aims of the project are to study effects of the two medications on cocaine dependence and craving, and on dopamine binding in the brain. At each assessment session, patients will undergo PET with [11C] raclopride to image the dopamine receptor DRD2. To trigger craving, patients will then be exposed to a videotape showing cocaine use; a questionnaire will be used to record their subjective responses, and a second PET scan will be performed with [18F] fluorodeoxyglucose (FDG) to image cerebral glucose metabolism during craving. This protocol was designed to enable us to study changes resulting from pharmacotherapy on dopamine binding in the brain, and on craving as reflected both in subjective measures and regional cerebral glucose metabolism. In addition, we will investigate the association between subjective measures of craving for cocaine and the level of dopamine DRD2 receptor occupancy in the brain before and after treatment. Notwithstanding the complexity of the clinical and therapeutic reality characterizing cocaine dependence, we hope to present preliminary evidence for the relative efficacy of these two promising medications in treatment for cocaine. dependence. This evidence could also elucidate the brain mechanisms underlying cocaine craving and dependence in cocaine-dependent patients.
An adaptive neural stress response is essential to adequately cope with a changing environment. It was previously argued that sympathetic/noradrenergic activity during acute stress increases salience network (SN) connectivity and reduces executive control network (ECN) connectivity in healthy controls, with opposing effects in the late aftermath of stress. Altered temporal dynamics of these networks in response to stress are thought to play a role in the development of psychopathology in vulnerable individuals.
We exposed male healthy controls (n = 40, mean age = 33.9) and unaffected siblings of schizophrenia patients (n = 39, mean age = 33.2) to the stress or control condition of the trier social stress test and subsequently investigated resting state functional connectivity of the SN and ECN directly after and 1.5 h after stress.
Acute stress resulted in increased functional connectivity within the SN in healthy controls, but not in siblings (group × stress interaction pfwe < 0.05). In the late aftermath of stress, stress reduced functional connectivity within the SN in both groups. Moreover, we found increased functional connectivity between the ECN and the cerebellum in the aftermath of stress in both healthy controls and siblings of schizophrenia patients.
The results show profound differences between siblings of schizophrenia patients and controls during acute stress. Siblings lacked the upregulation of neural resources necessary to quickly and adequately cope with a stressor. This points to a reduced dynamic range in the sympathetic response, and may constitute a vulnerability factor for the development of psychopathology in this at-risk group.
Background rotation causes different flow structures and heat transfer efficiencies in Rayleigh–Bénard convection. Three main regimes are known: rotation unaffected, rotation affected and rotation dominated. It has been shown that the transition between rotation-unaffected and rotation-affected regimes is driven by the boundary layers. However, the physics behind the transition between rotation-affected and rotation-dominated regimes are still unresolved. In this study, we employ the experimentally obtained Lagrangian velocity and acceleration statistics of neutrally buoyant immersed particles to study the rotation-affected and rotation-dominated regimes and the transition between them. We have found that the transition to the rotation-dominated regime coincides with three phenomena; suppressed vertical motions, strong penetration of vortical plumes deep into the bulk and reduced interaction of vortical plumes with their surroundings. The first two phenomena are used as confirmations for the available hypotheses on the transition to the rotation-dominated regime while the last phenomenon is a new argument to describe the regime transition. These findings allow us to better understand the rotation-dominated regime and the transition to this regime.
Small Island Developing States (SIDS) are island nations that experience specific social, economic and environmental vulnerabilities associated with small populations, isolation and limited resources. Globally, SIDS exhibit exceptionally high rates of non-communicable disease (NCD) risk and incidence. Despite this, there is a lack of context-specific research within SIDS focused on life course approaches to NCD prevention, particularly the impact of the early-life environment on later disease risk as defined by the Developmental Origins of Health and Disease (DOHaD) framework. Given that globalization has contributed to significant nutritional transitions in these populations, the DOHaD paradigm is highly relevant. SIDS in the Pacific region have the highest rates of NCD risk and incidence globally. Transitions from traditional foods grown locally to reliance on importation of Western-style processed foods high in fat and sugar are common. The Cook Islands is one Pacific SIDS that reports this transition, alongside rising overweight/obesity rates, currently 91%/72%, in the adult population. However, research on early-life NCD prevention within this context, as in many low- and middle-income countries, is scarce. Although traditional research emphasizes the need for large sample sizes, this is rarely possible in the smaller SIDS. In these vulnerable, high priority countries, consideration should be given to utilizing ‘small’ sample sizes that encompass a high proportion of the total population. This may enable contextually relevant research, crucial to inform NCD prevention strategies that can contribute to improving health and well-being for these at-risk communities.
This experimental study focuses on the effect of horizontal boundaries with pyramid-shaped roughness elements on the heat transfer in rotating Rayleigh–Bénard convection. It is shown that the Ekman pumping mechanism, which is responsible for the heat transfer enhancement under rotation in the case of smooth top and bottom surfaces, is unaffected by the roughness as long as the Ekman layer thickness
is significantly larger than the roughness height
. As the rotation rate increases, and thus
decreases, the roughness elements penetrate the radially inward flow in the interior of the Ekman boundary layer that feeds the columnar Ekman vortices. This perturbation generates additional thermal disturbances which are found to increase the heat transfer efficiency even further. However, when
, the Ekman boundary layer is strongly perturbed by the roughness elements and the Ekman pumping mechanism is suppressed. The results suggest that the Ekman pumping is re-established for
as the faces of the pyramidal roughness elements then act locally as a sloping boundary on which an Ekman layer can be formed.
Leafy vegetables are an essential component of a healthy diet; however, they have been associated with high-profile outbreaks causing severe illnesses. We reviewed leafy vegetable-associated outbreaks reported to the Centers for Disease Control and Prevention between 1973 and 2012. During the study period, 606 leafy vegetable-associated outbreaks, with 20 003 associated illnesses, 1030 hospitalizations, and 19 deaths were reported. On average, leafy vegetable-associated outbreaks were larger than those attributed to other food types. The pathogens that most often caused leafy vegetable-associated outbreaks were norovirus (55% of outbreaks with confirmed aetiology), Shiga toxin-producing Escherichia coli (STEC) (18%), and Salmonella (11%). Most outbreaks were attributed to food prepared in a restaurant or catering facility (85%). An ill food worker was implicated as the source of contamination in 31% of outbreaks. Efforts by local, state, and federal agencies to control leafy vegetable contamination and outbreaks should span from the point of harvest to the point of preparation.
In this chapter we ask what role Bovini play in ecosystems. We concentrate on some of the more unexpected impacts bovines have, and not on the fact that they serve as food for large predators, or that if they are not killed by these and have not been found by vultures, that they are devoured by maggots. We also do not concentrate on their role as nutrient recyclers. In that respect, the study of Vinod & Sabu (2007) illustrates well the cascading effects of the (local) extinction of large herbivores on the community structure of, in their case, dung beetles. In the wild, the dung of wild water buffalo, Bubalus arnee, is decomposed by fungi; flies and beetles and insects can be found in it, thus providing food for the red junglefowl, Gallus gallus, and green peafowl, Pavo muticus (Chaiyarat et al. 2004; also see Dean & MacDonald 1981; Middleton 2013). The dung of domestic yaks, Bos grunniens, is similarly used (Wu & Sun 2010). A hypothesis we ignore here suggests that large herbivores have a negative effect on reptile biomass (Janzen 1976). The reason to investigate would be that our experience is the opposite of one of Janzen’s suppositions, namely that large herbivores promote fire, and his other supposition that trampling would be bad for reptiles and amphibians. However, Friend & Taylor (1984) find both positive and negative effects of large herbivores. Other functions one normally does not think about include provision by water buffalo of blood meals for ticks, which may be infected with parasites, after which the buffalo can act as a reservoir for some diseases (Miranpuri 1988). Much literature on this subject is available (see, for example, Jongejan & Uilenberg 2004; Fyumagwa et al. 2007; Anderson et al. 2013 for African buffalo, Syncerus caffer, and ticks). It is also noteworthy that water buffalo were found to be near-free of ticks (Tulloch 1968).
Despite dietary recommendations that have repeatedly underscored the importance of increasing consumption of fruits and vegetables, intakes worldwide are lower than recommended levels. Consequently, the diets of many individuals may be lacking in nutrients and phytonutrients typical of a diet rich in a variety of fruits and vegetables. In the present study, we estimated phytonutrient intakes by adults categorised by sex, level of fruit and vegetable consumption ( < 5 v. ≥ 5 servings/d), and geographic diet cluster. Intakes of nine select phytonutrients were estimated from the 2002–4 World Health Survey fruit and vegetable servings intake data (n 198 637), the FAO supply utilisation accounts data, and phytonutrient concentration data obtained from the US Department of Agriculture databases and the published literature. Percentage contributions to each phytonutrient intake from fruit and vegetable sources were also estimated. Estimated intakes of phytonutrients from fruits and vegetables varied across the thirteen geographic diet clusters, reflecting regional differences in both numbers and proportions of fruit and vegetable servings consumed, and the specific types of fruits and vegetables available in the diet. The mean phytonutrient intakes by adults consuming ≥ 5 servings/d of fruits and vegetables were approximately 2- to 6-fold the mean phytonutrient intakes by adults with low fruit and vegetable consumption ( < 5 servings/d). In some cases, phytonutrient intakes by adults consuming ≥ 5 servings/d of fruits and vegetables in one geographic diet cluster were lower than the intakes by adults reporting < 5 servings/d in another cluster. The findings from this assessment provide important information regarding the major dietary patterns of phytonutrient intakes across geographic diet clusters.
Non-O157 Shiga toxin-producing Escherichia coli (STEC) infections are increasingly detected, but sources are not well established. We summarize outbreaks to 2010 in the USA. Single-aetiology outbreaks were defined as ⩾2 epidemiologically linked culture-confirmed non-O157 STEC infections; multiple-aetiology outbreaks also had laboratory evidence of ⩾2 infections caused by another enteric pathogen. Twenty-six states reported 46 outbreaks with 1727 illnesses and 144 hospitalizations. Of 38 single-aetiology outbreaks, 66% were caused by STEC O111 (n = 14) or O26 (n = 11), and 84% were transmitted through food (n = 17) or person-to-person spread (n = 15); food vehicles included dairy products, produce, and meats; childcare centres were the most common setting for person-to-person spread. Of single-aetiology outbreaks, a greater percentage of persons infected by Shiga toxin 2-positive strains had haemolytic uraemic syndrome compared with persons infected by Shiga toxin 1-only positive strains (7% vs. 0·8%). Compared with single-aetiology outbreaks, multiple-aetiology outbreaks were more frequently transmitted through water or animal contact.