Lena M. Johnson

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Type 1 diabetes (T1D) is a genetically complex disorder of glucose homeostasis that results from the autoimmune destruction of the insulin-secreting cells of the pancreas. Two previous whole-genome scans for linkage to T1D in 187 and 356 families containing affected sib pairs (ASPs) yielded apparently conflicting results, despite partial overlap in the(More)
Previous experiments examining the effects of adding a tandem fixed-ratio response requirement on fixed-interval schedule performance have reported inconsistent results. One variable that may account for such inconsistencies is the baseline response rate in the fixed-interval condition. This possibility was investigated in the present study. Rats were given(More)
OBJECTIVE To describe the sleep patterns and level of fatigue in children and adolescents (6-18 years of age) with HIV infection, compared with ethnic-, gender-, and age-matched healthy children in the home setting. DESIGN Descriptive, comparative. SETTING Conducted in each child's home environment. STUDY PARTICIPANTS Eighteen HIV-infected and 15(More)
This article has two main purposes. First, it introduces the discipline of historiography and, second, it provides a selected bibliography on the history of behavior analysis. In introducing the former in the context of the latter, four important methodological considerations involved in the process and product of historiography are described: The sources(More)
The effects of schedule history and the availability of an adjunctive response (polydipsia) on fixed-interval schedule performance were investigated. Two rats first pressed levers under a schedule of food reinforcement with an interresponse time greater than 11 s, and 2 others responded under a fixed-ratio 40 schedule. All 4 were then exposed to a(More)
The Microbial Identification System (MIS; Microbial ID, Inc., Newark, Del.) was evaluated for the identification of 550 clinically isolated yeasts. The organisms evaluated were fresh clinical isolates identified by methods routinely used in our laboratory (API 20C and conventional methods) and included Candida albicans (n = 294), C. glabrata (n = 145), C.(More)
A long-standing goal of speciation research is to describe how reproductive isolating barriers develop, when they arise along the ‘speciation continuum’, and to measure the strength with which they restrict gene flow. Drosophila arizonae and D. mojavensis are a recently diverged sister species pair distributed from the southwestern United States through(More)
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