Analysis and vulnerability of the international wheat trade network.

Wheat is one of the three basic cereals providing the necessary calorific intake for most of the world's population. For this reason, its trade is critical to many countries in order to fulfil their internal demand and strategic stocks. In this paper, we use complex network analysis tools to study the international wheat trade network and its evolving characteristics for the period 2009-2013. To understand the vulnerability of each country's dependence on the imports of this crop we have performed different analyses, simulating shocks of varying intensities for the main wheat producers, and observed the population affected by the production drop. As a result, we conclude that globally the network is slightly more resilient than four years previously, although at the same time some developing countries have slipped into a vulnerable situation. We have also analysed the effects of a global shock affecting all major producers, assessing its impact on every country. Some comments on the COVID-19 outbreak and the political decisions taken by governments following the pandemic declaration are included, observing that given their capital-intensive characteristics, no negative effects should currently be expected in the wheat market. Supplementary Information: The online version contains supplementary material available at 10.1007/s12571-020-01117-9.

A competing risks approach for time estimation of household WEEE disposal.

The recent growth in the number of electrical and electronic devices is viewed as one the priority waste streams in European Union waste management policy. This paper presents the findings of a survey to study domestic habits with respect to Waste Electrical and Electronic Equipment (WEEE) in Spain. A specific problem when performing this estimation arises from the fact that consumers quite often store old appliances at home when they are no longer used. Focusing on four different types of appliance, survival analysis (SA) is used to study both the usage span and the reasons for no longer using each device. The time that the discarded products were kept at home before being disposed of was studied using competing risks (CR) analysis. The results of the analysis provide information on the distribution of the studied variables for the different outcomes as well as the influence exerted by the socio-demographic variables considered. Relations between these characteristics and the storage time of the appliances before disposal emerge based on survey data. For instance, the CR model finds that the storage time of the some appliances (i.e. refrigerator) is related to these social-demographics factors. However, other appliances (i.e. microwave oven) are less influenced by these factors. The attitude and motivation of the respondents to the survey as regards the End-of-Life of appliances were also analysed. A majority of respondents do not store discarded appliances at home. The first reason for storing appliances at home is the possibility of it being useful in the future and the second that the respondents did not know what to do with them.

Influence of distance on the motivation and frequency of household recycling.

People choose to participate in recycling for a variety of reasons. This study analyzes the relationship between the frequency of selective separation and general refuse disposal, and the influence on the recycling habit of the walking distance to drop off the materials. The methodology employed was one of personal interviews in the street, the study population being a region in the north of Spain (Principality of Asturias). More than one thousand people participated in this survey carried out in 2002. Five hypotheses related to three variables (the frequency for depositing recycling materials and general refuse, the distance to recycling and general bins, and the recycling habit) were tested using different statistical tests. Results show that the people who frequently go to the bins to dispose of general refuse are more likely to recycle some product at home, and in most cases, as the distance to the recycling bins decreases, the number of fractions that citizens separate and collect at home increases. Most of the results obtained have been compared with other previous in literature.

Some comparative factors regarding recycling collection systems in regions of the USA and Europe.

This paper analyses whether differences in selective waste collection systems used commonly in Europe and America influence people's recycling habits and their opinions about the service they are offered. We study certain characteristics of the collection systems used in two specific areas-the Principality of Asturias (Northern Spain) and El Paso county (USA)-with very different practices. It likewise considers the extent to which such differences influence the recycling habits of the public at large, as well as their perceptions of the waste collection services. In order to carry out the research and to compare the influence of the above-mentioned factors in each case, personal interviews were held in the street in the two areas under study (1066 and 1068 interviews, respectively). Asturians needed less time to dispose of waste and separate items, being one of the reasons why this group has developed the habit of selective separation to a greater degree than El Pasoans.

Capacity planning in hospital nursing: a model for minimum staff calculation.

An aging population, emerging technology, heightening patient expectations, rising health care costs, shorter patient stays, and growing pressure to improve quality have made the management of nursing resources even more critical today. While approaching a model for staffing levels, the authors considered factors such as patient acuity, work redesign, and minimum quality standards. The methodology for analysis included estimating the time needed to complete nursing tasks and calculating the average number of tasks per patient. With respect to nursing quality measures, the study examined the adequacy of nursing documentation including admission history, assessments, nursing procedures, and discharge report as well as nursing-driven outcomes such as fall and phlebitis rates. Lastly, the authors determined the theoretical number of staff needed to provide nursing care according to quality standards.