加速评估有重要价值的药和

传统的临床试验方法可能延误救命治疗方法的利用，目前食品药物管理局的管理人员正在试图使速度与误差的风险相平衡。     

Did Kettlewell commit fraud? Re-examining the evidence

H.B.D. Kettlewell is famous for several investigations conducted in the early 1950s on the phenomenon of industrial melanism, which are widely regarded as the classic demonstration of natural selection. In a recent (2002) book-length popularization of this episode in the history of the science, science writer Judith Hooper draws attention to what she interprets as discrepancies in the results reported by Kettlewell in his first scientific papers on the subject. On the basis of correspondence among Kettlewell and his associates, a survey of scientific publications that mention outstanding questions surrounding the phenomenon, as well as interviews with his son, surviving colleagues, and scientists who have worked on industrial melanims, Hooper all but explicitly concludes that Kettlewell committed fraud. The following essay critically examines her evidence in support of this allegation, including her discussion of his character, the alleged motives, and whether fraud was even committed. None of Hooper's arguments is found to withstand careful scrutiny. The concluding section draws several conclusions about how history of science should be depicted to the public.     

Testing to enhance retention in human anatomy

Recent work in cognitive psychology has shown that repeatedly testing one's knowledge is a powerful learning aid and provides substantial benefits for retention of the material. To apply this in a human anatomy course for medical students, 39 fill-in-the-blank quizzes of about 50 questions each, one for each region of the body, and four about the nervous system, were developed. The quizzes were optional, and no credit was awarded. They were posted online using Blackboard, which provided feedback, and they were very popular. To determine whether the quizzes had any effect on retention, they were given in a controlled setting to 21 future medical and dental students. The weekly quizzes included questions on regional anatomy and an expanded set of questions on the nervous system. Each question about the nervous system was given three times, in a slightly different form each time. The second quiz was given approximately half an hour after the first one, and the third was given one week after the second to assess retention. The quizzes were unpopular, but students showed robust improvement on the questions about the nervous system. The scores increased by almost 9% on the second quiz, with no intervention except viewing the correct answers. The scores were 29% higher on the third quiz than on the first, and there was also a positive correlation between the grades on the quizzes and the final examination. Thus, repeated testing is an effective strategy for learning and retaining information about human anatomy.     

Local knowledge, environmental politics, and the founding of ecology in the United States. Stephen Forbes and "The Lake as a Microcosm" (1887)

Stephen Forbes's "The Lake as a Microcosm" is one of the founding documents of the science of ecology in the United States. By tracing the connections between scientists and local fishermen underlying the research on floodplain lakes presented in "The Lake as a Microcosm," this essay shows how the birth of ecology was tied to local knowledge and the local politics of environmental transformation. Forbes and the other scientists of the Illinois Natural History Survey relied on fishermen for manual labor, expertise in catching fish, and knowledge of the natural history of the fishes. As Forbes and his colleagues worked in close contact with fishermen, they also adopted many of their political concerns over the privatization of the floodplain and became politically active in supporting their interests. The close connection between scientists and local knowledge forced the ecologists to reframe the boundaries of ecology as objective or political, pure or applied, local or scientific.     

Visual attention in orienteers at different levels of experience

This study explored how differences in orienteering experience are related to differences in how visual attention is allocated to the map, the environment and to travel. Twenty more experienced and 20 less experienced individuals orienteered while wearing a head-mounted video camera with microphone. The participants verbalized what they were attending to (map, environment or travel) at any given time. Each recorded film was coded at each point in time in terms of what the participant was attending to and whether the participant was moving or stationary. More experienced orienteers attended to the map markedly more while moving and spent less time stationary than less experienced orienteers. The participants' performance was significantly related to the ability to attend to the map while moving. The strategic control of attention is proposed to explain this ability. It is proposed that attentional training might enhance performance in sports characterized by multiple and dynamically varying elements.     

Myths about moths: a study in contrasts

The phenomenon of industrial melanism is the preeminent example of natural selection in textbooks and the popular media. Much of its fame stems from a set of pioneering and apparently definitive investigations by H.B.D. 'Bernard' Kettlewell in the early 1950s. There is a marked contrast in how the phenomenon and Kettlewell's work on it are perceived by the public and scientists. Tensions between these two perceptions have recently led to calls for the removal of the example from textbooks, and indeed allegations that Kettlewell committed fraud. This article (part of the Science in the Industrial Revolution series) will show that these charges are baseless and stem from a fundamental misunderstanding of the nature of science as a process.     

Growth propagation of yeast in linear arrays of microfluidic chambers over many generations

The growth of microorganisms is often confined in restricting geometries. In this work, we designed a device to study the growth propagation of budding yeast along linear arrays of microfluidic chambers. Vacuum assisted cell loading was used to seed cells of limited numbers in the up-most chambers of each linear array. Once loaded, cells grow until confluent and then overgrow, pushing some of the newborns into the neighboring downstream chamber through connection channels. Such a scenario repeats sequentially along the whole linear chamber arrays. We observed that the propagation speed of yeast population along the linear arrays was strongly channel geometry dependent. When the connection channel is narrow and long, the amount of cells delivered into the downstream chamber is small so that cells grow over several generations in the same chamber before passing into the next chamber. Consequently, a population growth of more than 50 generations could be observed along a single linear array. We also provided a mathematical model to quantitatively interpret the observed growth dynamics.     

Compulsive-like behavior in individuals with Down syndrome: its relation to mental age level, adaptive and maladaptive behavior

This study examined the nature of repetitive, ritualistic, and compulsive-like behaviors in 50 typically developing children and 50 individuals with Down syndrome (DS), matched on mental age (MA; M = 59.72 months). Parents reported on their children's compulsive-like behaviors-including ritualistic habits-and perfectionistic behaviors, as well as their children's adaptive and maladaptive behaviors. Results indicated that children with DS show similar MA-related changes in compulsive-like behaviors compared to the MA-matched comparison group. Younger children (both typical and DS) exhibited significantly more compulsive-like behaviors than older children. In general, children with and without DS did not differ from each other in terms of the number of compulsive-like behaviors they engaged in, although participants with DS engaged in more frequent, more intense repetitive behaviors. Compulsive-like behaviors were differentially related to adaptive and maladaptive behaviors across the MA and mental retardation groups. The results extend the "similar sequence" model of development to the construct of compulsive-like behaviors, and also suggest that some repetitive behaviors may be among the behavioral phenotype of individuals with DS.