Diffusion of self-propelled particles in complex media

The diffusion of active microscopic organisms in complex environments plays an important role in a wide range of biological phenomena from cell colony growth to single organism transport. Here, we investigate theoretically and computationally the diffusion of a self-propelled particle (the organism) embedded in a complex medium comprised of a collection of non-motile solid particles that mimic soil or other cells. Under such conditions we find that the rotational relaxation time of the swimming direction depends on the swimming velocity and is drastically reduced compared to a pure Newtonian fluid. This leads to a dramatic increase (of several orders of magnitude) in the effective rotational diffusion coefficient of the self-propelled particles, which can lead to "self-trapping" of the active particles in such complex media. An analytical model is put forward that quantitatively captures the computational results. Our work sheds light on the role that the environment plays in the behavior of active systems and can be generalized in a straightforward fashion to understand other synthetic and biological active systems in heterogenous environments

Body image and body dysmorphic concerns

Most people would like to change something about their bodies and the way that they look, but for some it becomes an obsession. A healthy skin plays an important role in a person’s physical and mental wellbeing, whereas a disfiguring appearance is associated with body image concerns. Skin diseases such as acne, psoriasis and vitiligo produce cosmetic disfigurement and patients suffering these and other visible skin conditions have an increased risk of depression, anxiety, feelings of stigmatization and self-harm ideation. Body image affects our emotions, thoughts, and behaviours in everyday life, but, above all, it influences our relationships. Furthermore, it has the potential to influence our quality of life. Promotion of positive body image is highly recommended, as it is important in improving people’s quality of life, physical health, and health-related behaviors. Dermatologists have a key role in identifying body image concerns and offering patients possible treatment options

Aggregation dynamics of active rotating particles in dense passive media

Active matter systems are able to exhibit emergent non-equilibrium behavior due to activity-induced effective interactions between the active particles. Here we study the aggregation and dynamical behavior of active rotating particles, spinners, embedded in 2D passive colloidal monolayers. Using both experiments and simulations we observe aggregation of active particles or spinners whose behavior resembles classical 2D Cahn–Hilliard coarsening. The aggregation behavior and spinner attraction depend on the mechanical properties of the passive monolayer and the activity of spinners. Spinner aggregation only occurs when the passive monolayer behaves elastically and when the spinner activity exceeds a minimum activity threshold. Interestingly, for the spinner concentrations investigated here, the spinner concentration does not seem to change the dynamics of the aggregation behavior. There is a characteristic cluster size which maximizes spinner aggregation by minimizing the drag through the passive monolayer and maximizing the stress applied on the passive medium. We also show a ternary mixture of passive particles and co-rotating and counter-rotating spinners that aggregate into clusters of co and counter-rotating spinners respectivelyThis work was supported by Department of Energy BES award #ER46919 (theoretical and simulation work) and the Chang Family (experimental work)

The ESDAP diploma in psychodermatology

PS26 Psychodermatological consultations are a reality in most European countries nowadays. It is therefore important for health providers to be properly trained to deal with dermatological patients who present with specific needs. Throughout Europe, psychotherapy is being regulated and protected by law and the idea is for this diploma in Psychodermatology to be adapted to current regulations. ESDaP will offer these training courses on an international basis. Each teaching module offered will be the same in different European countries, and offered in different languages by a team of experts coordinated by an ESDaP EC member. The training program will consist of 3 levels. The levels and topics covered are as follows: Level 1: psychodermatologist, skin–psychologist, skin–psychiatrist. Acquiring competences in: doctor–patient relationship and communication skills, alexithymia, anxiety, depression, self-inflicted skin lesions, body dysmorphic disorders, delusion of parasitosis and other delusions, quality of life, psychopharmacological treatment, and psychological interventions. Level 2: Psychotherapeutic level A. Counsellor: first level dermatologist/psychologist/ psychiatrist trained as counsellor in various approaches (Habit reversal, atopy school, etc.) B. Practitioner: the same candidates reaching the requirements for the European Certificate in Psychotherapy Additionally, ESDaP will acknowledge and certify a multidisciplinary consultation dermatologist– psychologist/psychiatrist when one of the consultants reaches Level 2