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Summary The left–right (L–R) axis of most bilateral animals is established during gastrulation when a transient ciliated structure creates a directional flow of signaling molecules that establish asymmetric gene expression in the lateral plate mesoderm. However, in some animals, an earlier differential distribution of molecules and cell division patterns initiate or at least influence L–R patterning. Using single‐cell high‐resolution mass spectrometry, we previously reported a limited number of small molecule (metabolite) concentration differences between left and right dorsal‐animal blastomeres of the eight‐cellXenopusembryo. Herein, we examined whether altering the distribution of some of these molecules influenced early events in L–R patterning. Using lineage tracing, we found that injecting right‐enriched metabolites into the left cell caused its descendant cells to disperse in patterns that varied from those in control gastrulae; this did not occur when left‐enriched metabolites were injected into the right cell. At later stages, injecting left‐enriched metabolites into the right cell perturbed the expression of genes known to: (a) be required for the formation of the gastrocoel roof plate (foxj1); (b) lead to the asymmetric expression of Nodal (dand5/coco); or (c) result from asymmetricalnodalexpression (pitx2). Despite these perturbations in gene expression, we did not observe heterotaxy in heart or gut looping at tadpole stages. These studies indicate that altering metabolite distribution at cleavage stages at the concentrations tested in this study impacts the earliest steps of L–R gene expression that then can be compensated for during organogenesis.
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Closing the Wearable Gap—Part V: Development of a Pressure-Sensitive Sock Utilizing Soft Sensors
The purpose of this study was to evaluate the use of compressible soft robotic sensors (C-SRS) in determining plantar pressure to infer vertical and shear forces in wearable technology: A ground reaction pressure sock (GRPS). To assess pressure relationships between C-SRS, pressure cells on a BodiTrakTM Vector Plate, and KistlerTM Force Plates, thirteen volunteers performed three repetitions of three different movements: squats, shifting center-of-pressure right to left foot, and shifting toes to heels with C-SRS in both anterior–posterior (A/P) and medial–lateral (M/L) sensor orientations. Pearson correlation coefficient of C-SRS to BodiTrakTM Vector Plate resulted in an average R-value greater than 0.70 in 618/780 (79%) of sensor to cell comparisons. An average R-value greater than 0.90 was seen in C-SRS comparison to KistlerTM Force Plates during shifting right to left. An autoregressive integrated moving average (ARIMA) was conducted to identify and estimate future C-SRS data. No significant differences were seen in sensor orientation. Sensors in the A/P orientation reported a mean R2 value of 0.952 and 0.945 in the M/L sensor orientation, reducing the effectiveness to infer shear forces. Given the high R values, the use of C-SRSs to infer normal pressures appears to make the development of the GRPS feasible.
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- Award ID(s):
- 1827652
- PAR ID:
- 10181320
- Date Published:
- Journal Name:
- Sensors
- Volume:
- 20
- Issue:
- 1
- ISSN:
- 1424-8220
- Page Range / eLocation ID:
- 208
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.3390/s20010208
