Figure 1

Spaceflight-Induced Bone Tissue Changes that Affect Bone Quality and Increase Fracture Risk

Feb. 26, 2020

Purpose of Review Bone mineral density and systemic factors are used to assess skeletal health in astronauts. Yet, even in a general population, these measures fail to accurately predict when any individual will fracture. This review considers how long-duration human spaceflight requires evaluation of additional bone structural and material quality...

Graphical abstract

Additive manufacture of lightly crosslinked semicrystalline thiol-enes for enhanced mechanical performance.

Feb. 26, 2020

Photopolymerizable semicrystalline thermoplastics resulting from thiol-ene polymerizations were formed via fast polymerizations and achieved excellent mechanical properties. These materials have been shown to produce materials desirable for additive manufacturing (3D printing), especially for recyclable printing and investment casting. However, while well-resolved prints were previously achieved with the thiol-ene thermoplastics, the...

 Percent flocculation (%) as a function of flocculant dose (ppm) and flocculant molecular weight (g/mol) for cationic homopolymer flocculant (H-CAT) applied to a homogenous suspension of negatively-charged silica microparticles.

Flocculation behavior and mechanisms of block copolymer architectures on silica microparticle and Chlorella vulgaris systems

Feb. 26, 2020

Hypothesis Flocculation performance using polyelectrolytes is influenced by critical design parameters including molecular weight, amount and sign of the ionic charge, and polymer architecture. It is expected that systematic variation of these characteristics will impact not only flocculation efficiency (FE) achieved but that charge density and architecture, specifically, can alter...

Multifunctional PEG thiol and thioester norbornene macromers rapidly form hydrogels via the photoinitiated thiol-ene polymerization.

Phototunable Viscoelasticity in Hydrogels Through Thioester Exchange

Feb. 26, 2020

Mechanical cues are delivered to resident cells by the extracellular matrix and play an important role in directing cell processes, ranging from embryonic development and cancer metastasis to stem cell differentiation. Recently, cellular responses to viscoelastic and elastic mechanical cues have been studied; however, questions remain as to how cells...

Abstract

Dissociated Hippocampal Neurons Exhibit Distinct Zn2+ Dynamics in a Stimulation-Method-Dependent Manner

Feb. 26, 2020

Ionic Zn 2+ has increasingly been recognized as an important neurotransmitter and signaling ion in glutamatergic neuron pathways. Intracellular Zn 2+ transiently increases as a result of neuronal excitation, and this Zn 2+ signal is essential for neuron plasticity, but the source and regulation of the signal is still unclear...

Nutritional Zn2+ levels influence cell proliferation and intracellular Zn2+ levels.

Single cell analysis reveals multiple requirements for zinc in the mammalian cell cycle

Feb. 21, 2020

Zinc is widely recognized as essential for growth and proliferation, yet the mechanisms of how zinc deficiency arrests these processes remain enigmatic. Here we induce subtle zinc perturbations and track asynchronously cycling cells throughout division using fluorescent reporters, high throughput microscopy, and quantitative analysis. Zinc deficiency induces quiescence and resupply...

TFEA calculates motif enrichment using differential and positional information.

Transcription factor enrichment analysis (TFEA): Quantifying the activity of hundreds of transcription factors from a single experiment

Feb. 21, 2020

Detecting differential activation of transcription factors (TFs) in response to perturbation provides insight into cellular processes. Transcription Factor Enrichment Analysis (TFEA) is a robust and reliable computational method that detects differential activity of hundreds of TFs given any set of perturbation data. TFEA draws inspiration from GSEA and detects positional...

Endoplasmic reticulum tubules are a component of the ribonucleoprotein granule fission machinery.

Endoplasmic reticulum contact sites regulate the dynamics of membraneless organelles.

Feb. 21, 2020

Tethered interactions between the endoplasmic reticulum (ER) and other membrane-bound organelles allow for efficient transfer of ions and/or macromolecules and provide a platform for organelle fission. Here, we describe an unconventional interface between membraneless ribonucleoprotein granules, such as processing bodies (P-bodies, or PBs) and stress granules, and the ER membrane...

Graphical abstract

Tethering transforming growth factor β1 to soft hydrogels guides vascular smooth muscle commitment from human mesenchymal stem cells

Jan. 31, 2020

Mesenchymal stem cells (MSCs) hold great promise for vascular smooth muscle regeneration. However, most studies have mainly relied on extended supplementation of sophisticated biochemical regimen to drive MSC differentiation towards vascular smooth muscle cells (vSMCs). Herein we demonstrate a concomitant method that exploits the advantages of biomimetic matrix stiffness and...

Figure 2. Zigzag force ramp

Membrane-Protein Unfolding Intermediates Detected with Enhanced Precision Using a Zigzag Force Ramp

Jan. 31, 2020

Precise quantification of the energetics and interactions that stabilize membrane proteins in a lipid bilayer is a long-sought goal. Toward this end, atomic force microscopy has been used to unfold individual membrane proteins embedded in their native lipid bilayer, typically by retracting the cantilever at a constant velocity. Recently, unfolding...

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