Trading on time

The authors determine how time delays affect international trade using newly collected World Bank data on the days it takes to move standard cargo from the factory gate to the ship in 126 countries. They estimate a modified gravity equation, controlling for endogeneity and remoteness. On average, each additional day that a product is delayed prior to being shipped reduces trade by at least 1 percent. Put differently, each day is equivalent to a country distancing itself from its trade partners by 70 kilometers on average. Delays have an even greater impact on developing country exports and exports of time-sensitive goods, such as perishable agricultural products. In particular, a day's delay reduces a country's relative exports of time-sensitive to time-insensitive agricultural goods by 6 percent.Free Trade,Economic Theory&Research,Trade Policy,Common Carriers Industry,Transport and Trade Logistics

An ultra melt-resistant hydrogel from food grade carbohydrates

© 2017 The Royal Society of Chemistry. We report a binary hydrogel system made from two food grade biopolymers, agar and methylcellulose (agar-MC), which does not require addition of salt for gelation to occur and has very unusual rheological and thermal properties. It is found that the storage modulus of the agar-MC hydrogel far exceeds those of hydrogels from the individual components. In addition, the agar-MC hydrogel has enhanced mechanical properties over the temperature range 25-85 °C and a maximum storage modulus at 55 °C when the concentration of methylcellulose was 0.75% w/v or higher. This is explained by a sol-gel phase transition of the methylcellulose upon heating as supported by differential scanning calorimetry (DSC) measurements. Above the melting point of agar, the storage modulus of agar-MC hydrogel decreases but is still an elastic hydrogel with mechanical properties dominated by the MC gelation. By varying the mixing ratio of the two polymers, agar and MC, it was possible to engineer a food grade hydrogel of controlled mechanical properties and thermal response. SEM imaging of flash-frozen and freeze-dried samples revealed that the agar-MC hydrogel contains two different types of heterogeneous regions of distinct microstructures. The latter was also tested for its stability towards heat treatment which showed that upon heating to temperatures above 120 °C its structure was retained without melting. The produced highly thermally stable hydrogel shows melt resistance which may find application in high temperature food processing and materials templating

The development of drunk behaviour during evacuation

The intoxication of the occupants is hardly considered in the fire safety design, due to the lack of data on the subject. Recent research experiments into the influence of alcohol on evacuation have shown evidence that there might be a correlation between the development of drunk behaviour and the surroundings or context in which the occupants are situated. That is why the experiment in this report investigated the development of drunk behaviour in a group of people within a party environment, independently of alcohol, with the use of non-alcoholic beer as a placebo. The participants were put through 3 identical exercises, which were aimed at testing their balance, reaction times, concentration, hand to eye coordination, problem solving skills, cognitive skills and cooperation. In addition to that they performed 2 evacuations that were used to interrupt their ’drunk behaviour’ and test their reaction, decision and overall evacuation times. They were also analysed for signs of drunk behaviour with video and sound recordings. The results showed clear reduction of performance in the tests for concentration, hand to eye coordination, problem solving skills, cognitive skills and cooperation after the consumption of the beer, but little change in the balance tests. Apart from that, some of the participants showed signs of drunk behaviour, such as playfulness and increase in noise after the alcohol was consumed and these were reduced after the environment changed. Based on this it was concluded that even with non-alcoholic beer some of the participants developed drunk behaviour, like that observed in previous experiments with the use of alcohol