Bioinspired Micro/Nanomotors Towards Self-propelled Non-invasive Diagnosis and Treatment of Cancer

The last two decades have witnessed an extensive exploration of micro/nanomotors for effective biomedical diagnosis and therapy. A nanomotor is a tiny smart device inspired from biological motor that shows...

Pandemic planning: plotting a course through the coronawars

The biological motor behind the current coronavirus pandemic has placed microbiology on a global stage, and given its practitioners a role among the architects of recovery. Planning for a return to normality or the new normal is a complex, multi-agency task for which healthcare scientists may not be prepared. This paper introduces a widely used military planning framework known as the Joint Military Appreciation Process, and outlines how it can be applied to deal with the next phase of the COVID-19 pandemic. Recognition of SARS-CoV-2's critical attributes, targetable vulnerabilities, and its most likely and most dangerous effects is a necessary precursor to scoping, framing and mission analysis. From this flows course of action development, analysis, concept of operations development, and an eventual decision to act on the plan. The same planning technique is applicable to the larger scale task of setting a microbiology-centric plan in the broader context of social and economic recovery.

Energetic costs, precision, and efficiency of a biological motor in cargo transport

Molecular motors play key roles in organizing the interior of cells. An efficient motor in cargo transport would travel with a high speed and a minimal error in transport time (or distance) while consuming minimal amount of energy. The travel distance and its variance of motor are, however, physically constrained by energy consumption, the principle of which has recently been formulated into thethermodynamic uncertainty relation. Here, we reinterpret the uncertainty measure (𝒬) defined in the thermodynamic uncertainty relation such that a motor efficient in cargo transport is characterized with a small 𝒬. Analyses on the motility data from several types of molecular motors show that 𝒬 is a nonmonotic function of ATP concentration and load (f). For kinesin-1, 𝒬 is locally minimized at [ATP] ≈ 200μM andf≈ 4 pN. Remarkably, for the mutant with a longer neck-linker this local minimum vanishes, and the energetic cost to achieve the same precision as the wild-type increases significantly, which underscores the importance of molecular structure in transport properties. For the biological motors studied here, their value of 𝒬 is semi-optimized under the cellular condition ([ATP] ≈ 1 mM,f= 0 − 1 pN). We find that among the motors, kinesin-1 at single molecule level is the most efficient in cargo transport.

Conservation law for self-paced movements

Optimal control models of biological movements introduce external task factors to specify the pace of movements. Here, we present the dual to the principle of optimality based on a conserved quantity, called “drive,” that represents the influence of internal motivation level on movement pace. Optimal control and drive conservation provide equivalent descriptions for the regularities observed within individual movements. For regularities across movements, drive conservation predicts a previously unidentified scaling law between the overall size and speed of various self-paced hand movements in the absence of any external tasks, which we confirmed with psychophysical experiments. Drive can be interpreted as a high-level control variable that sets the overall pace of movements and may be represented in the brain as the tonic levels of neuromodulators that control the level of internal motivation, thus providing insights into how internal states affect biological motor control.

More than Meat and a Motor: The Diverse Biomechanical Roles of Skeletal Muscle and Their Place in ‘Semi-Living’ Machines

The biomechanical roles of skeletal muscle and their tendons are diverse. Perhaps most intuitively, muscle is regarded as a biological ‘motor’ that provides the work required for accelerating the body and overcoming aero- and hydrodynamic forces. With detailed biomechanical analyses, more intricate roles of the muscle-tendon unit have been uncovered, ranging from energy recyclers, to shock absorbers and capacitors. The functional scope of muscle-tendon tissue makes it an attractive choice for exploring bio-machine integration. Research and cross-disciplinary collaboration at SymbioticA offers a testbed for scientific and artistic exploration into engineered muscle-tendon constructs and the broader philosophical debate surrounding their place in ‘semi-living’ machine systems.