New technologies and decision making in out-of-hospital cardiac arrest

In this thesis, we performed analyses on basic life support, AED (automated external defibrillator) use by first responders (police, fire-fighters, and citizen-responders), and advanced life support by emergency medical services (EMS) in out-of-hospital cardiac arrest (OHCA). We studied the proportion of shockable initial rhythm over 10 years and showed that this proportion declined during the total study period, and remained stable when limiting the analysis to the last five years. We assessed the clinical benefit of the new AED algorithm cprINSIGHT which can analyze the heart rhythm during chest compressions. We showed that cprINSIGHT could make a shock/no-shock decision with high sensitivity (96%) and high specificity (98%) and led to a higher chest compression fraction and shorter pre-shock pauses compared to conventional AEDs. We gained more insight into patients transported without ROSC and showed that in this patient population the survival rate declined when time-on-scene before transport increased. We showed that in patients with prehospital ROSC, survivors had a significantly shorter time-to-ROSC compared to non-survivors and calculated that the time point for the decision to transport appears to be between 8 and 15 minutes after EMS arrival. We explored EMS decision-making on scene and found that known factors such as age, OHCA location, witnessed status and first rhythm only explained 36% of the variance in the decision to transport and other factors related to the patient, local circumstances, the paramedic, and the structure of the organization were identified as important additional themes contributing to the decision to transport a patient with ongoing CPR

Effects of retro-nasal aroma release on satiation

It is suggested that the brain response of a food odour sensed retro-nasally is related to satiation. The extent of retro-nasal aroma release during consumption depends on the physical structure of a food, i.e. solid foods generate a longer, more pronounced retro-nasal aroma release than liquid foods. The aim of this study was to investigate if a beverage becomes more satiating when the retro-nasal aroma release profile coincides with the profile of a (soft) solid food. In a double-blind placebo-controlled randomised cross-over full factorial design, twenty-seven healthy subjects (fourteen males and thirteen females; aged 16-65 years; BMI 19-37 kg/m(2) were administered aroma profiles by a computer-controlled stimulator based on air dilution olfactometry. Profile A consisted of a profile that is obtained during consumption of normal beverages. Profile B is normally observed during consumption of (soft) solids. The two profiles were produced with strawberry aroma and administered in a retro-nasal fashion, while the subjects consumed a sweetened milk drink. Before, during and after the sensory stimulation, appetite profile measurements were performed. Subjects felt significantly more satiated if they were aroma stimulated with profile B (P = 0.04). After stimulation with sweet strawberry aroma, there was a significant decrease in desire to eat sweet products (P = 0.0001). In conclusion, perceived satiation was increased by altering the extent of retro-nasal aroma release

Parental child-feeding strategies in relation to Dutch children's fruit and vegetable intake

Objective: To identify parental child-feeding strategies that may increase children's fruit or vegetable intake, since the relationship between these strategies and children's intake has never been investigated for fruit and vegetables as two separate food groups. Design: A survey study, where parents provided information about their practices in relation to feeding their children and about their own and their children's fruit and vegetable intake. Children completed a preference questionnaire about fruit and vegetables. To find underlying parental child-feeding strategies, factor analysis was applied to parents' practices in relation to fruit and vegetables separately. Regression analysis was used to predict the effect of these strategies on children's fruit and vegetable intake. The impact of the strategies was further analysed by estimating children's intake based on the frequency of use of specific strategies. Setting: The study was conducted at three primary schools in The Netherlands. Subjects: A total of 259 children between 4 and 12 years old and their parents (n242). Results: Parents used different strategies for fruit as compared with vegetables. The vegetable-eating context was more negative than the fruit-eating context. Parental intake and presenting the children with choice were positive predictors of children's intake of both fruit and vegetables. The intake difference based on frequency of use of the strategy 'Choice' was 40 g/d for vegetables and 72 g/d for fruit (

Renormalization of the quasiparticle hopping integrals by spin interactions in layered copper oxides

Holes doped within the square CuO2 network specific to the cuprate superconducting materials have oxygen 2p character. We investigate the basic properties of such oxygen holes by wavefunction-based quantum chemical calculations on large embedded clusters. We find that a 2p hole induces ferromagnetic correlations among the nearest-neighbor Cu 3d spins. When moving through the antiferromagnetic background the hole must bring along this spin polarization cloud at nearby Cu sites, which gives rise to a substantial reduction of the effective hopping parameters. Such interactions can explain the relatively low values inferred for the effective hoppings by fitting the angle-resolved photoemission data. The effect of the background antiferromagnetic couplings of renormalizing the effective nearest-neighbor hopping is also confirmed by density-matrix renormalization-group model Hamiltonian calculations for chains and ladders of CuO4 plaquettes