Increasing Returns to Education and Progress towards a College Degree

Returns to college have increased, but graduation rates have changed relatively little. Modifying a human capital model of college enrollment to endogenize time-to-graduation, we predict that higher returns to education will both speed graduation and increase enrollment. Some of those new entrants may, however, take longer to graduate. Using the 1989 and 1995 Beginning Postsecondary Studies, we employ a multinomial logit to model the association between individual and family characteristics, and five-year college outcomes: graduation, continued enrollment, and non-enrollment. Between cohort differences arise either because the characteristics of those entering college are different or because the relations between characteristics and outcomes have changed. We utilize a Oaxaca-Blinder style decomposition to distinguish between these two alternatives, attributing differences in characteristics to newly attracted students and differences in the relations between characteristics and outcomes to historically attracted students behaving differently. It is changes in behavior that explain the increased progress we observe.Higher Education, Graduation Rates, Persistence

Reported Progress under the Student Right-to-Know Act: How Reliable is It?

The Student Right-to-Know Act requires colleges to provide institution-specific information on graduation rates for students initially enrolling full-time in the fall term. Not all students enroll in that fashion, especially at two-year institutions. We use data on degree-seeking students from the 1996/2001 Beginning Post-Secondary Survey to identify students for whom statistics are and are not reportable under the Act and to track their progress. Results indicate the published progress rates are substantially higher than the progress rates for the non-reportable populations, whether students enter a two-year or a four-year institution. While progress rates for the two samples are significantly correlated within four-year institutions, they are not within two-year institutions. For those beginning at two-year institutions, the progress rates reported under the Student Right-to-Know Act are indicative of neither their absolute nor their relative (cross-institution) probability of success. Policy makers and prospective students will not make efficient decisions without better information.Efficiency, Resource Allocation, Graduation

Extensional viscosity of copper nanowire suspensions in an aqueous polymer solution

Suspensions of copper nanowires are emerging as new electronic inks for next-generation flexible electronics. Using a novel surface acoustic wave driven extensional flow technique we are able to perform currently lacking analysis of these suspensions and their complex buffer. We observe extensional viscosities from 3 mPa$\cdot$s (1 mPa$\cdot$s shear viscosity) to 37.2 Pa$\cdot$s via changes in the suspension concentration, thus capturing low viscosities that have been historically very challenging to measure. These changes equate to an increase in the relative extensional viscosity of nearly 12,200 times at a volume fraction of just 0.027. We also find that interactions between the wires and the necessary polymer additive affect the rheology strongly. Polymer-induced elasticity shows a reduction as the buffer relaxation time falls from 819 to 59 $\mu$s above a critical particle concentration. The results and technique presented here should aid in the future formulation of these promising nanowire suspensions and their efficient application as inks and coatings.Comment: 7 pages, 5 figures, under review for Soft Matter RS

The Development of a New Scale to Measure Food Insecurity Among Older Adults Using the International Classification of Functioning, Disability, and Health (ICF) Framework

Background: Older adults face different barriers to accessing adequate food, and none of the current food security scales address the unique issues that aging could present to food security among this population. Purpose: This study aims to understand the components of nutrition functioning in relation to food insecurity among older adults to develop a food insecurity screening tool specific to the older adult population. Methods: Cross-sectional qualitative study with semi-structured interviews. The interviews occurred via Google Voice and were simultaneously recorded using Zoom. Two researchers coded transcriptions from interview audio recordings separately, and thematic analysis based on the International Classification of Functioning, Disability, and Health (ICF) was used to analyze the data. The findings were deliberated between all the researchers, and the final themes, subthemes, and representative quotes were mutually agreed upon. Results: Twenty-three older adults living in independent senior living facilities were interviewed. Nine themes (transportation, access/variety, housing, mobility & aging, preparing food, interpersonal relationship, food assistance, dentition/ingestion/digestion, health conditions) and twenty-two subthemes were identified. The results demonstrated that lack of transportation, interpersonal relationships, health-related conditions, and financial constraints were this population\u27s principal barriers to accessing and preparing adequate food. Discussion: Food insecurity among older adults is a multi-dimension issue. A new scale to measure food insecurity among older adults was created to provide a more accurate assessment of food security risk in this population. Future research should validate this scale in different settings

Post Weaning Management of Heifer Calves Impacts ADG and Feed Efficiency as Pregnant Heifers

Replacement heifers were developed on cornstalks (Exp. 1, 2, and 3), dry lot (Exp. 1 and 2), or winter range (Exp. 3). In Exp. 1, pregnant heifers were individually fed during mid to late gestation. Heifers developed on cornstalks were more feed efficient than heifers developed in a dry lot. In Exp. 2 and 3, pregnant heifers grazed cornstalks during mid to late gestation. Heifers developed on cornstalks gained more and were more efficient, especially compared to heifers developed in a dry lot. These data provide evidence of an adaptive response to grazing low quality forages and may be beneficial in the critical period leading up to the first calving season

Type 3 ILCs in Lung Disease

The lungs represent a complex immune setting, balancing external environmental signals with a poised immune response that must protect from infection, mediate tissue repair, and maintain lung function. Innate lymphoid cells (ILCs) play a central role in tissue repair and homeostasis, and mediate protective immunity in a variety of mucosal tissues, including the lung. All three ILC subsets are present in the airways of both mice and humans; and ILC2s shown to have pivotal roles in asthma, airway hyper-responsiveness, and parasitic worm infection. The involvement of ILC3s in respiratory diseases is less well-defined, but they are known to be critical in homeostasis, infection and inflammation at other mucosal barriers, such as the gut. Moreover, they are important players in the IL17/IL22 axis, which is key to lung health. In this review, we discuss the emerging role of ILC3s in the context of infectious and inflammatory lung diseases, with a focus on data from human subjects

Combined 624-nm and 850-nm illumination at low rates leads to enhanced inhibition of Candida albicans

Background: To determine whether combinations of red and infrared light could improve inhibition of Candida albicans and whether combining wavelengths and altering rate of energy delivery could prevent the formation of resistance to light energy.Methods: C. albicans was tested because of the common appearance in human skin and mucous membrane infections. The organism was treated in vitro with a combination of 624-nm (red) and 850-nm (infrared) light emitted from a supraluminous diode (SLD) array. Doses of 9, and 30 J/cm2 were used. Rate of energy delivery was also manipulated. Colony counts were performed and compared to untreated controls using Student t tests and one-way ANOVA with Tukey post hoc analysis.Results: The combination of 624 and 850-nm light energy at 30 J/cm2 was an effective (p ≤ 0.05) inhibitor of C. albicans across all seven stages of the experiment. The combination of 624 and 850-nm wavelengths produced a maximum kill rate [{control – treated / control} X 100] of 76.24% and an average kill rate of 54% across the seven stages of the experiment.Conclusions: A Combination of 624-nm and 850-nm light from an SLD array can inhibit the growth of C. albicans in vitro. Altering delivery rate of the energy can delay resistance formation in this organism.

The Radio Continuum of the Metal-Deficient Blue Compact Dwarf Galaxy SBS0335-052

We present new Very Large Array observations at five frequencies, from 1.4 to 22GHz, of the extremely low-metallicity blue compact dwarf SBS0335-052. The radio spectrum shows considerable absorption at 1.49GHz, and a composite thermal+non-thermal slope. After fitting the data with a variety of models, we find the best-fitting geometry to be one with free-free absorption homogeneously intermixed with the emission of both thermal and non-thermal components. The best-fitting model gives an an emission measure EM ~ 8x10^7pc cm^{-6} and a diameter of the radio-emitting region D ~17pc. The inferred density is n_e ~ 2000 cm^{-3}. The thermal emission comes from an ensemble of \~9000 O7 stars, with a massive star-formation rate (>=5Msun) of 0.13-0.15 yr^{-1}, and a supernova rate of 0.006 yr^{-1}. We find evidence for ionized gas emission from stellar winds, since the observed Bralpha line flux significantly exceeds that inferred from the thermal radio emission. The non-thermal fraction at 5GHz is ~0.7, corresponding to a non-thermal luminosity of ~2x10^{20} W Hz^{-1}. We attribute the non-thermal radio emission to an ensemble of compact SN remnants expanding in a dense interstellar medium, and derive an equipartition magnetic field of ~0.6-1 mG, and a pressure of \~3x10^{-8}-1x10^{-7} dyne cm^{-2}. If the radio properties of SBS0335-052 are representative of star formation in extremely low-metallicity environments, derivations of the star formation rate from the radio continuum in high redshift primordial galaxies need to be reconsidered. Moreover, photometric redshifts inferred from ``standard'' spectral energy distributions could be incorrect.Comment: 25 pages, including 3 figures, accepted for publication in Ap