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101.

With the widespread availability of 3D food printing systems for purchase, users can customize their food in new ways. Manufacturer recommendations for cleaning these machines remain untested with regard to the prevention of foodborne pathogen transmission. This study aimed to determine if manufacturer cleaning recommendations for food ink capsules utilized in 3D food printers are adequate to control human norovirus (HuNoV). A HuNoV surrogate, Tulane virus (TuV; ~?6 log10 PFU/mL), was inoculated onto the interior surface of stainless steel food ink capsules. Capsules were either unsoiled or soiled with one of the following: butter, protein powder solution, powdered sugar solution, or a mixture containing all three food components. The capsules were allowed to dry and then one of three hygienic protocols was applied: manual washing (MW), a dishwasher speed cycle (DSC), or a dishwasher heavy cycle (DHC). The interaction effect between DSC and pure butter was a significant predictor of log reduction (P?=?0.0067), with the pure butter and DSC combination achieving an estimated mean log reduction of 4.83 (95% CI 4.13, 5.59). The DSC was the least effective method of cleaning when compared with MW and the DHC. The 3-way interaction effects between wash type, soil, and capsule position were a significant predictor of log reduction (P?=?0.00341). Capsules with butter in the DSC achieved an estimated mean log reduction of 2.81 (95% CI 2.80, 2.83) for the front-most position versus 6.35 (95% CI 6.33, 6.37) for the back-most position. Soil matrix, cleaning protocol, and capsule position all significantly impact capsule cleanability and potential food safety risk. The DHC is recommended for all capsules, and the corners should be avoided when placing capsules into the dishwasher. The current study seeks to provide recommendations for users of additive manufacturing and 3D food printing including consumers, restaurants, industry, and regulatory industries.

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Static and dynamic adsorption studies of Co (II) ions have been undertaken at fixed pH and ionic strength taking binary biopolymeric beads of cross-linked calcium alginate and carboxy methylcellulose as biosorbents. The adsorption data were applied to Langmuir and Freundlich isotherm equations and various static parameters were calculated. The dynamic nature of adsorption process was quantified in terms of several kinetic constants such as rate constants for adsorption (K) and Lagergreen rate constant (K ad). The influence of various experimental parameters such as solid-to-liquid ratio, pH, and temperature, the presence of salts and chemical composition of biopolymeric beads were investigated on the adsorption of cobalt ions.  相似文献   
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This paper criticises the conclusions and the unanswered questions in the National Institute of Standards and Technology (NIST)'s official report on the evacuation of the World Trade Center in New York City, United States, on 11 September 2001. It reviews the extent to which the report disregards several conventional statistical methods and comments on the NIST's refusal to share the machine‐readable data file with the scientific community for replication and further analysis. Problems lie in the sampling methods employed, the treatment of missing data, the use of ordinary least squares (OLS) with binary dependent variables, the failure to document the scalability of the scales used, the lack of tests to check for constant error variance, and the absence of overall fit tests of the model. There are also conceptual and theoretical issues, such as the absence in the report of considerations of the influence of group‐level processes and their impact on the collective behaviour of evacuating collectivities.  相似文献   
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Titanium dioxide (TiO2) is a widely used photocatalyst that has been demonstrated for microorganism disinfection in drinking water. In this study, a new material with a novel structure, silver and copper loaded TiO2 nanowire membrane (Cu-Ag-TiO2) was prepared and evaluated for its efficiency to inactivate E. coli and bacteriophage MS2. Enhanced photo-activated bactericidal and virucidal activities were obtained by the Cu-Ag-TiO2 membrane than by the TiO2, Ag-TiO2 and Cu-TiO2 membranes under both dark and UV light illumination. The better performance was attributed to the synergies of enhanced membrane photoactivity by loading silver and copper on the membrane and the synergistic effect between the free silver and copper ions in water. At the end of a 30 min test of deadend filtration under 254 nm UV irradiation, the Cu-Ag-TiO2 membrane was able to obtain an E. coli removal of 7.68 log and bacteriophage MS2 removal of 4.02 log, which have met the US EPA standard. The free metal ions coming off the membrane have concentrations of less than 10 ppb in the water effluent, far below the US EPA maximum contaminant level for silver and copper ions in drinking water. Therefore, the photo-activated disinfection by the Cu-Ag-TiO2 membrane is a viable technique for meeting drinking water treatment standards of microbiological water purifiers.
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This study investigates the factors determining an individual's response to official recommended protective measures, based on the Health Belief Model and the Protective Action Decision Model, to understand the adoption of protective behaviour during an H7N9 (Avian Influenza A) emergency. A public survey involving 1,375 respondents was conducted in Anhui Province, China, during the 2013 H7N9 outbreak to test the research model and hypotheses. The results indicate that protective, stakeholder, and risk perceptions influence positively an individual's willingness to take recommended actions. Protective and stakeholder perceptions also have a positive bearing on lay people's risk perceptions. A stakeholder perception is a vital determinant of a protective perception. More importantly, the effects of protective and stakeholder perceptions on behavioural responses to recommendations are mediated in part by risk perception. These findings can help public health officials to develop messages to encourage members of the population to protect themselves effectively during an influenza crisis.  相似文献   
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The main constraints on energy exploration in the Australian arid zone are logistic, with limited additional constraints from Aboriginal reserves. The main consequence is increased access, with possible introduction of weeds and expansion of tourism and cattle grazing in consequence.  相似文献   
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