A foodborne norovirus outbreak in a nursing home and spread to staff and their household contacts.

On 16 March 2018, a nursing home notified a possible acute gastroenteritis outbreak that affected 11 people. Descriptive and case-control studies and analysis of clinical and environmental samples were carried out to determine the characteristics of the outbreak, its aetiology, the transmission mechanism and the causal food. The extent of the outbreak in and outside the nursing home was determined and the staff factors influencing propagation were studied by multivariate analysis. A turkey dinner on March 14 was associated with the outbreak (OR 4.22, 95% CI 1.11-16.01). Norovirus genogroups I and II were identified in stool samples. The attack rates in residents, staff and household contacts of staff were 23.49%, 46.22% and 22.87%, respectively. Care assistants and cleaning staff were the staff most frequently affected. Cohabitation with an affected care assistant was the most important factor in the occurrence of cases in the home (adjusted OR 6.37, 95% CI 1.13-36.02). Our results show that staff in close contact with residents and their household contacts had a higher risk of infection during the norovirus outbreak.

Indirect vs direct assessment of gastric emptying: A randomized crossover trial comparing C-isotope breath analysis and MRI.

BACKGROUND: Indirect methods to assess gastric emptying (GE), such as 13 C breath tests (BT), are commonly used. However, BT usually use a sampling time of 4+ hours. The current study aims to assess the validity of BT for four liquid meals differing in physicochemical properties. To this aim, we compared them to MRI GE-measurements. METHODS: Fifteen healthy males (age 22.6 ± 2.4 years, BMI 22.6 ± 1.8 kg/m2 ) participated in a randomized 2 × 2 crossover experiment. Test foods were liquid meals, which were either thin/thick and 100/500 kcal, labeled with 100 mg of 13 C-octanoate. GE was measured with MRI and assessed by 13 C recovery from breath. Participants were scanned every 10 minutes and at six time points breath samples were collected up to t = 90 minutes. Two curves were fitted to the data to estimate emptying halftime (t50 Ghoos and t50 Bluck ). T50 times were ranked per participant and compared between methods. KEY RESULTS: On average, MRI and BT showed similar t50 rankings for the four liquid meals. In comparison to MRI, t50 Ghoos overestimated, while t50 Bluck underestimated GE time. Moreover, more viscous foods were overestimated. In most participants individual t50 time rankings differed significantly between methods. CONCLUSIONS & INFERENCES: BT can assess relative emptying differences on group level and collecting breath data for 90 minutes constitutes a lower burden for participants and the research facility. However, BT has severe shortcomings compared to MRI for individual GE assessment. Notably, food matrix effects should be considered when interpreting the results of BT.

Thermal activation of non-radiative Auger recombination in charged colloidal nanocrystals.

Applications of semiconductor nanocrystals such as biomarkers and light-emitting optoelectronic devices require that their fluorescence quantum yield be close to 100%. However, such quantum yields have not been obtained yet, in part, because non-radiative Auger recombination in charged nanocrystals could not be suppressed completely. Here, we synthesize colloidal core/thick-shell CdSe/CdS nanocrystals with 100% quantum yield and completely quenched Auger processes at low temperatures, although the nanocrystals are negatively photocharged. Single particle and ensemble spectroscopy in the temperature range 30-300 K shows that the non-radiative Auger recombination is thermally activated around 200 K. Experimental results are well described by a model suggesting a temperature-dependent delocalization of one of the trion electrons from the CdSe core and enhanced Auger recombination at the abrupt CdS outer surface. These results point to a route for the design of core/shell structures with 100% quantum yield at room temperature.

What would Batman eat?: priming children to make healthier fast food choices.

BACKGROUND: Fast food patronage is a frequent reality for many children and their parents. Although there are increasingly healthier alternatives for popular menu items (apple slices instead of French fries), they are infrequently selected. OBJECTIVES: We investigated whether either of two priming tactics - the priming of a role model's food choices or the priming of healthy foods - could influence children to make healthier fast food choices. METHODS: In the priming model condition, 22 children (ranging in age from 6 to 12 years) were presented with 12 photos of 6 admirable and 6 less admirable models and asked, 'Would this person order apple fries or French fries?' In the health prime condition, the same children were shown 12 photos of 6 healthy foods and 6 less healthy foods and asked to indicate if each food was healthy or unhealthy. RESULTS: When children were asked what various admirable people - such as Batman or Spiderman - would eat, 45% chose apple slices over French fries, which was higher than the health prime (P < 0.001) or the control condition (P < 0.001). CONCLUSIONS: Advising a parent to ask their child 'What would Batman (or another admired character or person) eat?' might be an easy step to take in what could be a healthier fast food world.