Rhyme: A Tool for Word Learning

To become successful readers, children must be able to recognize how changes in sound correspond to changes in word meaning. Rhymes, which contain minimal pair words that differ in their initial phoneme but share final vowels and codas (e.g., the cat in the hat), are often used in preschool and kindergarten classrooms as a tool to promote literacy and word learning. Although young language learners can generally discriminate minimal pair words, they often show difficulty when asked to assign them as labels for separate novel objects. The present experiment investigated the role of experience with rhyme on the mapping of minimal pair words to novel objects. Fourteen-month-old infants participated in two conditions, a Rhyme condition and a Repetition condition, administered one week apart. Order of presentation was randomized across participants. In the Rhyme condition, infants were familiarized with a nonsense story that contained 12 target rhyming words (e.g., fin, hin, zin) along with 28 non-rhyming filler words, arranged into rhythmic couplets (e.g., Lat kin mo lu vin, Pab roo mip fi nin). In the Repetition condition, infants were familiarized with a second nonsense story in which the target words repeated (e.g., Lat rin mo lu rin, Pab roo mip fi rin). Following familiarization, infants were presented with two novel object-label pairs (e.g., bin/gak paired with Object A and din/pak paired with Object B). Learning of these object-label associations was then tested using a Visual Choice Procedure, where both objects appeared simultaneously while a single label was presented in a carrier phrase (e.g., Look at the bin! Bin!). Accuracy and reaction time to target were assessed through offline coding of infant eye gaze data. No significant effect was found for Condition or Target Label. Results suggest infants did not sufficiently learn the novel object-label pairs and perhaps, more referential support or a less cognitively demanding task than the one used in the current study is needed to map minimal pairs

The Voice of Low-Income Adolescent Mothers on Infant Feeding

Adolescent mothers\u27 feeding practices impact infant weight gain. Infant obesity, especially in low-income families, is rapidly increasing. The aim of the exploratory study reported here was to identify factors affecting low-income African American and non-Hispanic White adolescent mothers\u27 infant feeding practices and useful learning modalities. Two focus groups were conducted by a trained facilitator using a semi-structured topic guide. Three themes emerged: (1) feeding decisions related to introduction of solid foods; (2) feeding information/advice provided by others; and (3) useful learning strategies. These themes can be used by Extension professionals in designing nutrition education programs for adolescent mothers

Elastic free energy drives the shape of prevascular solid tumors

It is well established that the mechanical environment influences cell functions in health and disease. Here, we address how the mechanical environment influences tumor growth, in particular, the shape of solid tumors. In an in vitro tumor model, which isolates mechanical interactions between tumor cells and a hydrogel, we find that tumors grow as ellipsoids, resembling the same, oft-reported observation of in vivo tumors. Specifically, an oblate ellipsoidal tumor shape robustly occurs when the tumors grow in hydrogels that are stiffer than the tumors, but when they grow in more compliant hydrogels they remain closer to spherical in shape. Using large scale, nonlinear elasticity computations we show that the oblate ellipsoidal shape minimizes the elastic free energy of the tumor-hydrogel system. Having eliminated a number of other candidate explanations, we hypothesize that minimization of the elastic free energy is the reason for predominance of the experimentally observed ellipsoidal shape. This result may hold significance for explaining the shape progression of early solid tumors in vivo and is an important step in understanding the processes underlying solid tumor growth.Comment: Six figures in main text. Supporting Information with 6 additional figure

Nanoscale Channels and Tunnels in Surface-Modified Poly(dimethylsiloxane).

Exposing the elastomer polydimethylsiloxane (PDMS) to oxygen plasma creates a very thin, stiff, and brittle surface-modified layer. Nano-scale crack patterns can be introduced to this layer with tensile stress. To optimize the pattern formation for a specific nano- or bio-technology research application, the surface-modified layer must be fully characterized. A characterization method was developed, using a combination of experiments and finite-element modeling. Phase imaging and nanoindentation with the atomic force microscope showed that the surface-modified layer was graded over approximately 200 nm, with an elastic modulus at the surface approximately ten-times that of the unmodified PDMS. Finite-element analyses indicated that the toughness of the surface-modified layer is extremely low (0.1 – 0.3 J/m2) and that the embrittlement extends 100 – 400 nm below that of the measured layer thickness, signifying that the cracks may extend deeper than the apparent layer thickness. Variations of the nanocrack-patterning method were used to produce functional nanoscale patterns. First, surface-modified PDMS cubes and microspheres were uniaxially compressed causing their surfaces to be decorated with nanocrack patterns. Pattern formation, due to the distribution of tensile stresses in the surface-modified layer, on the cube surfaces was associated with friction at the contacts with the platens; whereas, for the microspheres it could exclusively be attributed to the changing cross-sectional area along the axis of compression. Second, an array of parallel tunnel cracks was produced in the surface-modified layer, when sandwiched between PDMS substrates, with an applied uniaxial tensile strain. The tunnel cracks functioned as tunable nanochannels when they connected pre-patterned microchannel reservoirs. Modulated fluidic transport of single particles between the reservoirs was demonstrated and electrical resistance measurements confirmed the nanochannel adjustability (from approximately 1 μm wide to completely closed). Due to the compliance of PDMS, surface forces were able to cause the channel and tunnel cracks to close, or heal, upon removal of applied tensile strain. The self-adhesion of the nanochannel walls due to surface forces was studied and the conditions for collapse were determined. A method for determining and applying a non-uniform traction on the surface of bodies that are interacting due to surface forces was developed.Ph.D.Mechanical EngineeringUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/61680/1/klmills_1.pd

Infusing Critical Thinking into Communication Courses

The importance of critical thinking is generally recognized by educators and during the past 20 years numerous initiatives have been taken to improve critical thinking. Although research demonstrates courses in communication study can have a positive impact on critical thinking skills, we argue that instruction in critical thinking can be more explicitly covered in basic communication courses. This article details our efforts to infuse critical thinking into an entrylevel communication course and outlines a guide to help communication teachers integrate critical thinking into their courses

ResearchCOVID‐19 Preparedness in Michigan Nursing Homes

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/155466/1/jgs16490_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/155466/2/jgs16490.pd