Publications by authors named "J Christen"

The hazard function represents one of the main quantities of interest in the analysis of survival data. We propose a general approach for parametrically modelling the of the hazard function using systems of autonomous ordinary differential equations (ODEs). This modelling approach can be used to provide qualitative and quantitative analyses of the evolution of the hazard function over time.

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Reticulocyte-binding protein homologue 5 (RH5), a leading blood-stage Plasmodium falciparum malaria vaccine target, interacts with cysteine-rich protective antigen (CyRPA) and RH5-interacting protein (RIPR) to form an essential heterotrimeric "RCR-complex". We investigate whether RCR-complex vaccination can improve upon RH5 alone. Using monoclonal antibodies (mAbs) we show that parasite growth-inhibitory epitopes on each antigen are surface-exposed on the RCR-complex and that mAb pairs targeting different antigens can function additively or synergistically.

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Did the dramatic learning losses from remote learning in the context of COVID-19 stem at least partly from schools having overlooked students' socio-emotional skills-such as their ability to self-regulate emotions, their mental models, motivation, and grit-during the emergency transition to remote learning? We study this question using a cluster-randomized control trial with 18,256 high-school students across 87 schools in the State of Goiás, Brazil. The intervention sent behavioral nudges through text messages to students or their caregivers, targeting their socio-emotional skills during remote learning. Here we show that these messages significantly increased standardized test scores relative to the control group, preventing 7.

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The bake hardening value is one of the vital strength indexes of dual-phase steel, representing the strengthening ability of materials after pre-strain and baking, playing an important role in vehicle safety and lightweight design. Studying and improving the strain aging mechanism of dual-phase steel helps one to understand the material characteristics and enhances its utilization value. However, the ultra-high strength dual-phase steel is often prone to fracture outside the gauge length of a tensile specimen of the bake hardening value test.

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We present the design, fabrication, and in vivo testing of an ultra-thin (100 μm) wireless and battery-free implant for stimulation of the brain's cortex. The implant is fabricated on a flexible and transparent parylene/PDMS substrate, and it is miniaturized to dimensions of 15.6 × 6.

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