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Hoverflies (Diptera, Syrphidae) are cosmopolitan, generalist flower visitors and among the most important pollinators after bees and bumblebees. The dronefly Eristalis tenax can be found in temperate and continental climates across the globe, often synanthropically. Eristalis tenax pupae of different generations and different climate zones are thus exposed to vastly different temperatures. In many insects, the ambient temperature during the pupal stage affects development, adult size, and survival; however, the effect of developmental temperature on these traits in hoverflies is comparatively poorly understood. We here reared E. tenax pupae at different temperatures, from 10°C to 25°C, and quantified the effect on adult hoverflies. We found that pupal rearing at 17°C appeared to be optimal, with high eclosion rates, longer wings, and increased adult longevity. Rearing temperatures above or below this optimum led to decreased eclosion rates, wing size, and adult survival. Similar thermal dependence has been observed in other insects. We found that rearing temperature had no significant effect on locomotor activity, coloration or weight, despite evidence of strong sexual dimorphism for each of these traits. Our findings are important as hoverflies are key pollinators, and understanding the effects of developmental temperature could potentially be useful for horticulture.

Many animals use motion vision information to control dynamic behaviors. Predatory animals, for example, show an exquisite ability to detect rapidly moving prey, followed by pursuit and capture. Such target detection is not only used by predators but is also important in conspecific interactions, such as for male hoverflies defending their territories against conspecific intruders. Visual target detection is believed to be subserved by specialized target-tuned neurons found in a range of species, including vertebrates and arthropods. However, how these target-tuned neurons respond to actual pursuit trajectories is currently not well understood. To redress this, we recorded extracellularly from target-selective descending neurons (TSDNs) in male Eristalis tenax hoverflies. We show that they have dorso-frontal receptive fields with a preferred direction up and away from the visual midline. We reconstructed visual flow fields as experienced during pursuits of artificial targets (black beads). We recorded TSDN responses to six reconstructed pursuits and found that each neuron responded consistently at remarkably specific time points but that these time points differed between neurons. We found that the observed spike probability was correlated with the spike probability predicted from each neuron's receptive field and size tuning. Interestingly, however, the overall response rate was low, with individual neurons responding to only a small part of each reconstructed pursuit. In contrast, the TSDN population responded to substantially larger proportions of the pursuits but with lower probability. This large variation between neurons could be useful if different neurons control different parts of the behavioral output.

The ability to visualize small moving objects is vital for the survival of many animals, as these could represent predators or prey. For example, predatory insects, including dragonflies, robber flies and killer flies, perform elegant, high-speed pursuits of both biological and artificial targets. Many non-predatory insects, including male hoverflies and blowflies, also pursue targets during territorial or courtship interactions. To date, most hoverfly pursuits have been studied outdoors. To investigate hoverfly (Eristalis tenax) pursuits under more controlled settings, we constructed an indoor arena that was large enough to encourage naturalistic behavior. We presented artificial beads of different sizes, moving at different speeds, and filmed pursuits with two cameras, allowing subsequent 3D reconstruction of the hoverfly and bead position as a function of time. We show that male E. tenax hoverflies are unlikely to use strict heuristic rules based on angular size or speed to determine when to start pursuit, at least in our indoor setting. We found that hoverflies pursued faster beads when the trajectory involved flying downwards towards the bead. Furthermore, we show that target pursuit behavior can be broken down into two stages. In the first stage, the hoverfly attempts to rapidly decreases the distance to the target by intercepting it at high speed. During the second stage, the hoverfly's forward speed is correlated with the speed of the bead, so that the hoverfly remains close, but without catching it. This may be similar to dragonfly shadowing behavior, previously coined ‘motion camouflage’.

Responding rapidly to visual stimuli is fundamental for many animals. For example, predatory birds and insects alike have amazing target detection abilities, with incredibly short neural and behavioral delays, enabling efficient prey capture. Similarly, looming objects need to be rapidly avoided to ensure immediate survival, as these could represent approaching predators. Male Eristalis tenax hoverflies are nonpredatory, highly territorial insects that perform high-speed pursuits of conspecifics and other territorial intruders. During the initial stages of the pursuit, the retinal projection of the target is very small, but this grows to a larger object before physical interaction. Supporting such behaviors, E. tenax and other insects have both target-tuned and loom-sensitive neurons in the optic lobes and the descending pathways. We here show that these visual stimuli are not necessarily encoded in parallel. Indeed, we describe a class of descending neurons that respond to small targets, to looming and to wide-field stimuli. We show that these descending neurons have two distinct receptive fields where the dorsal receptive field is sensitive to the motion of small targets and the ventral receptive field responds to larger objects or wide-field stimuli. Our data suggest that the two receptive fields have different presynaptic input, where the inputs are not linearly summed. This novel and unique arrangement could support different behaviors, including obstacle avoidance, flower landing, and target pursuit or capture.

In 2016, the only undergraduate program in health promotion and prevention (HP) in Switzerland to date was launched at the Zurich University of Applied Sciences. HP in Switzerland is well institutionalized and anchored in health politics, but the profession of HP practitioners is not well established yet. The conceptualization of HP as outlined in the Ottawa Charta makes it quite complex to teach and learn HP within an undergraduate program. The program (180 ECTS) is offered as a full-time (3 years) and part-time (5 years) program to a maximum of 66 students. The outlined learning outcomes are based on the CompHP to ensure international transferability of HP competencies. The focus is on a threefold methodological approach, consisting of (1) practical training, (2) skills training (research, project management, and communication), and (3) interprofessional training. Experiences with 5 years of program implementation have revealed challenges, e.g., adapting the form of study to the current trend of flexible education to enable more self-directed learning opportunities and promoting better employability of the graduates. By providing a supportive learning environment for HP, the program contributes to publicity and quality assurance in practice and policy of HP in Switzerland and internationally.

Die Zielgruppe der Jugendlichen und jungen Erwachsenen ist im Kontext der Corona-Pandemie in den Fokus gerückt. Wie wichtig es ist, die Gesundheit der Jugendlichen und jungen Erwachsenen zu fördern, wird durch diese Fokussierung betont. Vor diesem Hintergrund ist es wichtig, die wissenschaftlichen Grundlagen als Basis für wirksame Massnahmen und Interventionen zu aktualisieren. So ist sichergestellt, dass die Grundlage für Programme und Projekte auf dem neuesten Stand ist. Der vorliegende Bericht zeigt, weshalb sich ein Engagement für die Gesundheit von Jugendlichen und jungen Erwachsenen lohnt. Aufbauend auf wissenschaftlichen Erkenntnissen wird gezeigt, warum die Themen Bewegung, Ernährung und psychische Gesundheit wichtige Pfeiler für die Gesundheit im Jugend- und jungen Erwachsenenalter sind. Es werden Interventionen und bewährte Handlungsansätze und Empfehlungen vorgestellt. Autorinnen und Autoren: Kapitel 1 Einleitung und Kapitel 10 Schlussfolgerungen: Dr. phil. Fabienne Amstad Kapitel 2 Lebensphase: Prof. Dr. med. Joan-Carles Suris, Dr. Yara Barrense-Dias Kapitel 3 Grundlagen: Prof. Dr. med. Julia Dratva, Matthias Meyer, dipl. SozÖk, Prof. Dr. phil. Karin Nordström Kapitel 4 Chancengleichheit: lic. phil. Dominik Weber Kapitel 5 Medien: MSc Jael Bernath, Prof. Dr. Daniel Süss Kapitel 6 Bewegung: Prof. Dr. Suzanne Suggs Kapitel 7 Ernährung: Dr. Sophie Bucher Della Torre Kapitel 8 Psychische Gesundheit: Prof. Dr. Frank Wieber, Prof. Dr. Agnes von Wyl, Dr. Annina Zysset Kapitel 9 Zusammenspiel: MSc Ronia Schiftan, MSc Anne-Françoise Wittgenstein Mani

In personalized nutrition, food is a tool for good health, implying an instrumental relationship between food and health. Food receives a secondary value, while health would appear to be a descriptive biological concept. This article gives an introduction to cultural understandings of food and health. The wider definition of food and health is explored in relation to the commonly used scientific approach that tends to take a more reductionist approach to food and health. The different discourses on food and health are being discussed in relation to ethical aspects of personalized nutrition. The success of personalized nutrition is likely dependent upon the ability to integrate the scientific approach with everyday cultural, emotional, ethical, and sensual understandings of food. Health theories can be divided into two principal rival types—biostatistical and holistic. Biostatistical focuses on survival, while holistic focuses on ability as a precondition for health. Arguments in favor of a holistic and individualistic theory of health and illness are presented. This implies a focus on the ability of the individual to realize his or her “vital goals.” A holistic and individualistic health concept may have a reinforcing effect on the individualized approach in personalized nutrition. It allows focus on individual health premises and related dietary means of health promotion, as well as an individualized perspective on the objectives of health promotion. An individualistic notion of health also indicates that people with high levels of vital goals benefit more easily. To reach beyond these groups is likely difficult. This potential injustice should be balanced with global preventive medical programs.

This study explores how and why abuse and neglect occurs in geriatric institutions and presents practical prevention measures. Exploratory qualitative interviews were carried out with purposive sample of 23 nursing staff members. They were recruited from different institutions caring for older patients in the north-western region of Switzerland. These interviews were analyzed using thematic analysis. Participating nursing staff members reported several factors pertaining to the care provider, the older patient, and the institution that precipitated abuse and neglect. They mentioned different solutions that could help them address their responsibilities in a reasonable manner. The solutions included, for example, ensuring proper education and training, better management nursing care provider's responsibilities and timely intervention to address abuse and neglect, as well as rotating care provider. Implementing these suggestions will allow geriatric institutions, its managers, and nursing care providers to improve quality of care and reduce such negative occurrences in these settings.

The idea of personalized nutrition (PN) is to give tailored dietary advice based on personal health-related data, i.e. phenotoype, genotype, or lifestyle. PN may be seen as part of a general trend towards personalised health care and currently various types of business models are already offering such services in the market. This paper explores ethical issues of PN by examining how PN services within the contextual environment of four future scenarios about health and nutrition in Europe might affect aspects of social justice according to Martha Nussbaum’s capability approach. The scenarios have been created by a mixed group of stakeholders and experts in three consecutive workshops. This resulted in the definition of four future scenarios within a scenario space consisting of two variables: the ‘logic of health care systems’ and ‘conception of health’. Within each scenario, PN is likely to play a more or less important role in improving health by influencing food consumption patterns in society. Nussbaum’s capability approach implies a concept of social justice as a function of a minimum standard of human dignity. This denotes an account for equality in terms of a minimum of entitlements. However, also the ability of achieving individual objectives is essential for social justice. Personalisation advice in health and food consumption patterns, as aimed for by PN, is therefore acceptable provided a minimum of entitlements is guaranteed to all members of a society, and at the same time freedom concerning personal preferences is respected. Potential variation of how different people might benefit from PN should therefore be consistent with the minimum required as defined by the list of capabilities.