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Evaluates a collaborative program in which high achieving biology students participate in genetics research under the guidance and supervision of a geneticist. Reviews the impact of their participation on college and career choices as well as understanding of science methodology, genetics, agricultural science, and product development. (SOE)

Many attempts have been made to address the problem of teenage premarital sexual activity in order to reduce the number of pregnancies and sexually transmitted diseases. The authors review some of those efforts and attempt to identify effective approaches. Implications for research are also presented. (Author)

To understand the mechanisms of neuronal [Zn.sup.2+] homeostasis better, experimental data obtained from cultured cortical neurons were used to inform a series of increasingly complex computational models. Total metals (inductively coupled plasma-mass spectrometry), resting metallothionein, [sup.65][Zn.sup.2+] uptake and release, and intracellular free [Zn.sup.2+] levels using ZnAF-2F were determined before and after neurons were exposed to increased [Zn.sup.2+], either with or without the addition of a [Zn.sup.2+] ionophore (pyrithione) or metal chelators [EDTA, clioquinol (CQ), and N,N,N',N'-tetrakis(2-pyridylmethyl)ethylenediamine]. Three models were tested for the ability to match intracellular free [Zn.sup.2+] transients and total [Zn.sup.2+] content observed under these conditions. Only a model that incorporated a muffler with high affinity for [Zn.sup.2+], trafficking [Zn.sup.2+] to intracellular storage sites, was able to reproduce the experimental results, both qualitatively and quantitatively. This 'muffler model' estimated the resting intracellular free [Zn.sup.2+] concentration to be 1.07 nM. If metallothionein were to function as the exclusive cytosolic [Zn.sup.2+] muffler, the muffler model predicts that the cellular concentration required to match experimental data is greater than the measured resting concentration of metallothionein. Thus [Zn.sup.2+] buffering in resting cultured neurons requires additional high-affinity cytosolic metal binding moieties. Added CQ, as low as 1 [micro]M, was shown to selectively increase [Zn.sup.2+] influx. Simulations reproduced these data by modeling CQ as an ionophore. We conclude that maintenance of neuronal [Zn.sup.2+] homeostasis, when challenged with [Zn.sup.2+] loads, relies heavily on the function of a high-affinity muffler, the characteristics of which can be effectively studied with computational models. muffler; zinc buffering; computational model; metal ion transport and homeostasis; metallothionein

Understanding the cognitive processes involved in multi-alternative, multi-attribute choice is of interest to a wide range of fields including psychology, neuroscience, and economics. Prior investigations in this domain have relied primarily on choice data to compare different theories. Despite numerous such studies, results have largely been inconclusive. Our study uses state-of-the-art response-time modeling and data from 12 different experiments appearing in six different published studies to compare four previously proposed theories/models of these effects: multi-alternative decision field theory (MDFT), the leaky-competing accumulator (LCA), the multi-attribute linear ballistic accumulator (MLBA), and the associative accumulation model (AAM). All four models are, by design, dynamic process models and thus a comprehensive evaluation of their theoretical properties requires quantitative evaluation with both choice and response-time data. Our results show that response-time data is critical at distinguishing among these models and that using choice data alone can lead to inconclusive results for some datasets. In conclusion, we encourage future research to include response-time data in the evaluation of these models. [ABSTRACT FROM AUTHOR]

Cellular cytoskeletal mechanics plays a major role in many aspects of human health from organ development to wound healing, tissue homeostasis and cancer metastasis. We summarize the state‐of‐the‐art techniques for mathematically modeling cellular stiffness and mechanics and the cytoskeletal components and factors that regulate them. We highlight key experiments that have assisted model parameterization and compare the advantages of different models that have been used to recapitulate these experiments. An overview of feed‐forward mechanisms from signaling to cytoskeleton remodeling is provided, followed by a discussion of the rapidly growing niche of encapsulating feedback mechanisms from cytoskeletal and cell mechanics to signaling. We discuss broad areas of advancement that could accelerate research and understanding of cellular mechanobiology. A precise understanding of the molecular mechanisms that affect cell and tissue mechanics and function will underpin innovations in medical device technologies of the future. WIREs Syst Biol Med 2018, 10:e1407. doi: 10.1002/wsbm.1407 This article is categorized under: Models of Systems Properties and Processes > Mechanistic Models Physiology > Mammalian Physiology in Health and Disease Models of Systems Properties and Processes > Cellular Models [ABSTRACT FROM AUTHOR]