The emergence of bacterial antibiotic resistance is a growing problem, yet the variables that influence rate are not well understood. In microfluidic device designed to mimic naturally occurring niches, Escherichia coli ciprofloxacin developed within 10 hours. Resistance emerged with as few 100 bacteria in initial inoculation. Whole-genome sequencing resistant organisms revealed four functional single-nucleotide polymorphisms attained fixation. Knowledge about rapid heterogeneous conditions...

We show here that upconversion phosphors can be imaged both by infrared excitation and in a scanning electron microscope. have synthesized characterized for this work up-converting phosphor nanoparticles nonaggregated nanocrystals of size range 50−200 nm. investigated the optical properties nm found square dependence emitted visible fluorescence on verified under similar narrow band emission spectra obtained as is seen with IR upconversion. The viability biological imaging was confirmed...

Abstract From flocking birds to swarming insects, interactions of organisms large and small lead the emergence collective dynamics. Here, we report striking swimming bovine sperm in dynamic clusters, enabled by viscoelasticity fluid. Sperm oriented same direction within each cluster, cluster size cell-cell alignment strength increased with In contrast, swam randomly individually Newtonian (nonelastic) fluids low high viscosity. Analysis fluid motion surrounding individual indicated that...

We demonstrate that upstream swimming of sperm emerges via an orientation disorder-order transition. The order parameter, the average head against flow, follows a 0.5 power law with deviation from critical flow shear rate ($\ensuremath{\gamma}\ensuremath{-}{\ensuremath{\gamma}}_{c}$). This transition is successfully explained by hydrodynamic bifurcation theory, which extends to broad class near surface microswimmers possess front-back asymmetry and circular motion.

The copy number of any protein fluctuates among cells in a population; characterizing and understanding these fluctuations is fundamental problem biophysics. We show here that distributions measured under broad range biological realizations collapse to single non-Gaussian curve scaling by the first two moments. Moreover, all experiments variance found depend quadratically on mean, showing degree freedom determines entire distribution. Our results imply do not reflect specific molecular or...

Significance Mammalian females must selectively allow sperm with normal morphology and motility to ascend the reproductive tract while rejecting invasion of pathogens. By using microfluidic modeling, we revealed that microgrooves gentle fluid flows, two major biophysical characteristics female tract, synergistically provide preferential pathways for sperm. In contrast, sexually transmitted pathogen, Tritrichomonas foetus , is swept away from these pathways. These findings are not only...

Successful reproduction in mammals requires sperm to swim against a fluid flow and through the long complex female reproductive tract before reaching egg oviduct. Millions of them do not make it. Despite their clinical importance, roles played migration by diverse biophysical biochemical microenvironments within are largely unknown. In this article, we present development double layer microfluidic device that recreates two important environments tract: surface topography. The unique feature...

Malignant tumors are often associated with an elevated fluid pressure due to the abnormal growth of vascular vessels, and thus increased interstitial flow out tumors. Recent in vitro works revealed that flows critically regulated tumor cell migration within a three dimensional biomatrix, breast cancer behavior depended sensitively on seeding density, chemokine availability rates. In this paper, we focus role modulating heterogeneity motility phenotype biomatrix. Using newly developed...

In mammals, many sperm that reach the oviduct are held in a reservoir by binding to epithelium. To leave reservoir, detach from epithelium; however, they may bind and again as ascend into ampulla toward oocytes. order elucidate nature of interactions along oviduct, we compared effects bursts strong fluid flow (as would be caused oviductal contractions), heparin, hyperactivation on detachment bovine bound vitro epithelium intact folds isthmic ampullar mucosa. Intact mucosa were used represent...

Upconverting nanoparticles (UCNPs) when excited in the near-infrared (NIR) region display anti-Stokes emission whereby emitted photon is higher energy than excitation energy. The material system achieves that by converting two or more infrared photons into visible photons. use of confers benefits to bioimaging because its deeper penetrating power biological tissues and lack autofluorescence. We demonstrate here sub-10 nm, upconverting rare earth oxide UCNPs synthesized a combustion method...

New drug development is costly, time-consuming, and has a low success rate, leading to decline in discovery efficiency over time. Drug repurposing emerged as an effective alternative, applying existing, safe drugs new diseases, thereby reducing time costs by bypassing preclinical toxicology testing. With the increasing availability of large-scale interaction data (e.g., drug-protein, protein-protein, drug-disease networks) advancements generative AI, opportunities have arisen for discovery....

This work introduces a contact line pinning based microfluidic platform for the generation of interstitial and intramural flows within three dimensional (3D) microenvironment cellular behaviour studies. A method was used to confine natively derived biomatrix, collagen, in channels without walls. By patterning collagen designated wall-less channels, we demonstrated validated through channel bounded by monolayer endothelial cells (mimic vascular vessel), as well slow cell laden matrix using...

Cells with different cohesive properties self-assemble in a spatiotemporal and context-dependent manner. Previous studies on cell self-organization mainly focused the spontaneous structural development within short period of time during which numbers remained constant. However effect proliferation over cells is largely unexplored. Here, we studied dynamics co-culture MDA-MB-231 MCF10A seeded well defined space (i.e. non-adherent microfabricated wells). When cell-growth was chemically...

Collective swimming is evident in the sperm of several mammalian species. In bull ( Bos taurus ) sperm, high viscoelasticity surrounding fluid induces to form dynamic clusters. Sperm within clusters swim closely together and align same direction, yet are because individual into out them over time. As part female reproductive tract contains mucus and, consequently, highly viscoelastic, this mechanistic clustering likely happens vivo . Nevertheless, it has been unclear whether could provide...

Flocking behavior is observed in biological systems from the cellular to superorganismal length scales, and mechanisms purposes of this are objects intense interest. In paper, we study collective dynamics bovine sperm cells a viscoelastic fluid. These appear not spontaneously flock, but transition into long-lived flocking phase after being exposed transient ordering pulse fluid flow. Surprisingly, induced has many qualitative similarities with spontaneous polar phases predicted by Toner-Tu...

The integration of a hydrogel-based chemical gradient generator and an array format microhabitats allows for fast screening optimal conditions microalgal growth.

Obstructed by hurdles in information extraction, handling and processing, computer-assisted sperm analysis systems have typically not considered detail the complex flagellar waveforms of spermatozoa, despite their defining role cell motility. Recent developments imaging techniques data processing produced significantly improved methods waveform digitization. Here, we use these improvements to demonstrate that near-complete capture is realizable on scale hundreds cells, and, further,...

Multiphoton microscopy is a powerful technique for achieving three-dimensional submicron imaging in biological specimens. However, specimen optical parameters such as refractive indices and scattering coefficients can result the loss of image resolution decreased signal depth. These factors are coupled to focusing objective's numerical aperture (NA) limiting achievable depths. In this work, we performed multiphoton on aqueous fluorescent solution, human skin, rat tail tendon show that, under...

In this paper, we address the hydraulic flow of fluids on and within nanofabricated hydrophilic (as opposed to hydrophobic) surfaces, influence an extended precursor film wetting dynamics water penetrating a nano-textured array posts that has no sealing surface (open-top). The width in front edge δ is extraordinarily large, approximately 2 mm for our device, it drives penetration open-top array. We discuss way thin controls movement macroscopic Lw its posts. Rapid controllable transport...

Feedback control of spiral waves by the phases tip is investigated experimentally in a light-sensitive Belousov-Zhabotinsky reaction. The rotation (Psi(r)) and meandering (Psi(m)) are obtained real time during experiments. It found that, for both rigid rotating spirals, one can manipulate spirals to move with any arbitrary paths feedback signals derived from Psi(r). Synchronization between dynamics be induced when Psi(m) Psi(r) used simultaneously as signals. Experimental findings compared...

Nanochannels offer a way to align and analyze long biopolymer molecules such as DNA with high precision at potentially single basepair resolution, especially if means detect biomolecules in nanochannels electronically can be developed. Integration of electronics will require the development nanochannel fabrication procedures that not damage sensitive previously constructed on device. We present here near-room-temperature technology involving parylene-C conformal deposition is compatible...

Abstract In this work, we compared the performance of objectives with similar numerical aperture 0.75 but different immersion media air, water, glycerin, and oil in imaging human skin epithelium dermis. general, found that objective recorded strongest intensity at same mechanical depth. We also characterized focal shifts decreasing refractive index, shift becomes increasingly more negative (for both dermis). dermis, estimated image resolution depths 18.8 30.2 μm, were comparable these under...