Fluctuating Nonlinear Spring Model of Mechanical Deformation of Biological Particles

We present a new theory for modeling forced indentation spectral lineshapes of biological particles, which considers non-linear Hertzian deformation due to an indenter-particle physical contact and bending deformations of curved beams modeling the particle structure. The bending of beams beyond the critical point triggers the particle dynamic transition to the collapsed state, an extreme event leading to the catastrophic force drop as observed in the force (F)-deformation (X) spectra. The theory interprets fine features of the spectra: the slope of the FX curves and the position of force-peak signal, in terms of mechanical characteristics --- the Young's moduli for Hertzian and bending deformations E_H and E_b, and the probability distribution of the maximum strength with the strength of the strongest beam F_b^* and the beams' failure rate m. The theory is applied to successfully characterize the $FX$ curves for spherical virus particles --- CCMV, TrV, and AdV

Glass reflow on 3-dimensional micro-apertures for electrophysiological measurements on-chip

We propose a new method to fabricate micro-apertures for on-chip electrophysiological measurements of living cells. Thermal reflow of phosphosilicate glass (PSG) is applied to funnel- or nozzle-type microstructures to generate very smooth surfaces on the finalized chip. Such 3-dimensional microstructures show close similarities to fire-polished glass pipette tips. Immobilized cells fit perfectly to these structures offering a large contact area for sealing between the cell membrane and the oxide surface. A tight cell/chip-aperture seal is an important requirement for the present application. We demonstrate the formation of stable gigaseals with Chinese hamster ovary (CHO) cells for both types of microstructures without the need of any post-fabrication surface treatment. By adjusting the PSG reflow parameters, the shape of the apertures can be modified and diameters down to the sub-micrometer range may be achieved. The application of PSG reflow to MEMS fabrication is an interesting new option to create unconventional microstructure

Incident heart failure risk after bariatric surgery:the role of epicardial fat

This commentary refers to 'Surgical obesity treatment and the risk of heart failure', by S. Jamaly et al., 2019;40:2131-2138

On the war-episodes in "Hikayat Kuda Semirang Sira Panji Pandai Rupa"

This paper, based on the text of the Jakarta MS C. St. 125 published by Lukman Ali and M.S. Hutagalung (1996), shows by a comparative reading of selected samples of war-episodes in the hikayat, that, in spite of the countless differences between them, all ultimately tell one and the same underlying story. This story is in each war-episode retold in a process of constant variation within identity. This is done by combining “pre-fab” units that each form a slot in an already predetermined narrative structure. Each of these slots is filled with a selection of type-scenes, made from the particular string of type-scenes that is available for that particular slot. In order to shed light on the question where the hikayat’s author may have found the models and inspiration for its composition, the numerous intertextual echoes of Javanese and Malay literary genres and individual works audible in these war-episodes are also traced.</div

Physics of viral dynamics

Viral capsids are often regarded as inert structural units, but in actuality they display fascinating dynamics during different stages of their life cycle. With the advent of single-particle approaches and high-resolution techniques, it is now possible to scrutinize viral dynamics during and after their assembly and during the subsequent development pathway into infectious viruses. In this Review, the focus is on the dynamical properties of viruses, the different physical virology techniques that are being used to study them, and the physical concepts that have been developed to describe viral dynamics

Caught in a vicious cycle? Explaining bidirectional spillover between parent-child relationships and peer victimization

Relationships with parents and peers are crucial for children's socialization, but how parent-child and peer relationships mutually affect each other is not well understood. Guided by spillover theory, we zoomed in on the bidirectional interplay between parental rejection and warmth on the one hand and peer victimization on the other, and examined whether children's maladjustment symptoms mediated hypothesized cross-domain spillover effects. Data stem from five waves of the longitudinal KiVa study among 9,770 children (50% boys; mean age = 9.16, standard deviation = 1.29). Results from random intercept cross-lagged panel models showed that higher parental rejection and lower parental warmth predicted increases in peer victimization and vice versa across waves, thus supporting the bidirectional model. Moreover, spillover from parent-child rejection and warmth to peer victimization was partially driven by children's depressive symptoms and bullying perpetration. Vice versa, spillover from peer victimization to parent-child rejection and warmth was partially driven by children's social anxiety, depressive symptoms, conduct problems, and bullying perpetration. Thus, children might get caught in persistent problems in two important social domains, and these two domains influence each other through children's maladjustment. Family and school interventions should be integrated to prevent a downwards spiral

The Systematic Application of Network Diagnostics to Monitor and Tackle Bullying and Victimization in Schools

Despite increased attention to tackling bullying and the use of effective anti-bullying programs that can reduce victimization for many, some children remain victimized. Preventing persistent victimization requires that teachers identify victims and intervene at an early stage, but this is often difficult because teachers cannot always recognize victimization or the underlying social dynamics that determine what kind of interventions are necessary. This proposal discusses how network diagnostics of the social structure of the classroom can help teachers to recognize and reduce victimization more systematically. First, it discusses research that shows promising effects of the use of network diagnostics to reduce health problems. It describes how these diagnostics (for bullying and victimization, social position, and school well-being) can help in recognizing victimization and tailoring interventions to the most relevant students. Second, this proposal discusses a systematic stepwise approach for teachers to interpret the diagnostics and translate them into structural actions. Overall, this proposal aims to raise awareness of the potential of network information to facilitate the daily practice of reducing bullying and gives researchers directions for further empirical research on teachers’ role in tackling bullying and on the situations that may affect whether their approaches are effective. Moreover, it discusses potential barriers to teachers’ use of network diagnostics, such as a lack of time and resources at school

An illness-focused interactive booklet to optimise management and medication for childhood fever and infections in out-of-hours primary care: study protocol for a cluster randomised trial

Background Fever is the most common reason for a child to be taken to a general practitioner (GP), especially during out-of-hours care. It is mostly caused by self-limiting infections. However, antibiotic prescription rates remain high, especially during out-of-hours care. Anxiety and lack of knowledge among parents, and perceived pressure to prescribe antibiotics amongst GPs, are important determinants of excessive antibiotic prescriptions. An illness-focused interactive booklet has the potential to improve this by providing parents with information about fever self-management strategies. The aim of this study is to develop and determine the effectiveness of an interactive booklet on management of children presenting with fever at Dutch GP out-of-hours cooperatives. Methods/design We are conducting a cluster randomised controlled trial (RCT) with 20 GP out-of-hours cooperatives randomised to 1 of 2 arms: GP access to the illness-focused interactive booklet or care as usual. GPs working at intervention sites will have access to the booklet, which was developed in a multistage process. It consists of a traffic light system for parents on how to respond to fever-related symptoms, as well as information on natural course of infections, benefits and harms of (antibiotic) medications, self-management strategies and ‘safety net’ instructions. Children < 12 years of age with parent-reported or physician-measured fever are eligible for inclusion. The primary outcome is antibiotic prescribing during the initial consultation. Secondary outcomes are (intention to) (re)consult, antibiotic prescriptions during re-consultations, referrals, parental satisfaction and reassurance. In 6 months, 20,000 children will be recruited to find a difference in antibiotic prescribing rates of 25% in the control group and 19% in the intervention group. Statistical analysis will be performed using descriptive statistics and by fitting two-level (GP out-of-hours cooperative and patient) random intercept logistic regression models. Discussion This will be the first and largest cluster RCT evaluating the effectiveness of an illness-focused interactive booklet during GP out-of-hours consultations with febrile children receiving antibiotic prescriptions. It is hypothesised that use of the booklet will result in a reduced number of antibiotic prescriptions, improved parental satisfaction and reduced intention to re-consult