The stable homotopy category, much studied by algebraic topologists, is a closed symmetric monoidal category. For many years, however, there has been no well-behaved closed symmetric monoidal category of spectra whose homotopy category is the stable homotopy category. In this paper, we present such a category of spectra; the category of symmetric spectra. Our method can be used more generally to invert a monoidal functor, up to homotopy, in a way that preserves monoidal structure. Symmetric spectra were discovered at about the same time as the category of S S -modules of Elmendorf, Kriz, Mandell, and May, a completely different symmetric monoidal category of spectra.

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Ninety-eight newborn infants, less than 34 weeks at birth, were studied to examine the relationship between newborn hypotension and hypoxemia and brain damage. Heart rate, blood pressure and oxygen tension were recorded continuously during the 96 h following delivery. Outcome measures included neuropathology in children who died, and motor and cognitive development at one year corrected age in children who survived. There were 22 children with a minor and 27 with a major abnormal outcome. There was a relationship between newborn hypotension, newborn hypoxemia and low birth weight, and a major abnormal outcome. The probability of a major abnormal outcome increased from 8% in newborns with no hypotension or hypoxemia, to 53% in children with both hypotension and hypoxemia. These findings support the contention that combinations of sustained newborn hypotension and hypoxemia are important factors in the development of brain damage, accounting for a major abnormal outcome.

Background Students who are the first in their families to attend college are an integral part of undergraduate engineering programs. Growing bodies of research argue that educators could better support these students if they understood the unique backgrounds, experiences, and knowledge they bring with them to higher education. Purpose/Hypothesis The purpose of this article is twofold. First, we identify salient funds of knowledge used by a group of first‐generation college students in their educational and work‐related experiences. Secondly, we use the funds of knowledge identified in our participants' experiences to create a survey instrument. Design/Method A mixed methods approach was used. Ethnographic interview data of six first‐generation college students were used to hypothesize constructs and create survey items. Survey data were collected from 812 students. Exploratory and confirmatory factor analyses were used to verify the underlying theoretical structures among the survey items and hypothesized constructs. Results Validity evidence supported a 10‐factor model as opposed to the hypothesized 6‐factor model. The 10 latent constructs that make up the funds of knowledge instrument are as follows: tinkering knowledge from home, tinkering knowledge from work, connecting experiences, networks from family members, networks from college friends, networks from coworkers, networks from neighborhood friends, perspective taking, reading people, and mediating ability. Conclusions Recognizing first‐generation college students' funds of knowledge is a first step to creating curricular spaces and experiences that better serve them. A survey scale allows educators to empirically examine how these accumulated bodies of knowledge are transmitted to capital, create advantages in engineering, and provides a useful tool to bridge students' knowledge in the classroom.

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