Effects of motor preparation and spatial attention on corticospinal excitability in a delayed-response paradigm

The preparation of motor responses during the delay period of an instructed delay task is associated with sustained neural firing in the primate premotor cortex. It remains unclear how and when such preparation-related premotor activity influences the motor output system. In this study, we tested modulation of corticospinal excitability using single-pulse transcranial magnetic stimulation (TMS) during a delayed-response task. At the beginning of the delay interval participants were either provided with no information, spatial attentional information concerning location but not identity of an upcoming imperative stimulus, or information regarding the upcoming response. Behavioral data indicate that participants used all information available to them. Only when information concerning the upcoming response was provided did corticospinal excitability show differential modulation for the effector muscle compared to other task-unrelated muscles. We conclude that modulation of corticospinal excitability reflects specific response preparation, rather than non-specific event preparation

Steam-Electric Scale Economies and Construction Lead Times

There was a widespread belief in the 1970s that the construction of coal and nuclear generating units exhibited positive economies of scale. Recent empirical literature has confirmed this belief for coal plants. But these studies have not considered the relationships among cost, plant size, and the building period. This paper derives and estimates a model in which construction cost and lead time are jointly determined. Constant returns to scale are not rejected for nuclear units. While coal units may exhibit positive returns to scale, because larger plants take longer to build, these returns are lower than previously estimated

Alien Registration- Titus, Rothwell S. (Auburn, Androscoggin County)

https://digitalmaine.com/alien_docs/30542/thumbnail.jp

Prognostic significance of short-term blood pressure variability in acute stroke

Background and Purpose— Blood pressure variability (BPV) may be an important prognostic factor acutely after stroke. This review investigated the existing evidence for the effect of BPV on outcome after stroke, also considering BPV measurement techniques and definitions. Methods— A literature search was performed according to a prespecified study protocol. Two reviewers independently assessed study eligibility and quality. Where appropriate, meta-analyses were performed to assess the effect of BPV on poor functional outcome. Results— Eighteen studies from 1359 identified citations were included. Seven studies were included in a meta-analysis for the effect of BPV on functional outcome (death or disability). Systolic BPV was significantly associated with poor functional outcome: pooled odds ratio per 10-mm Hg increment, 1.2; confidence interval (1.1–1.3). A descriptive review of included studies also supports these findings, and in addition, it suggests that systolic BPV may be associated with increased risk of intracranial hemorrhage in those treated with thrombolytic therapy. Conclusions— This systematic review and meta-analysis suggest that greater systolic BPV, measured early from ischemic stroke or intracerebral hemorrhage onset, is associated with poor longer-term functional outcome. Future prospective studies should investigate how best to measure and define BPV in acute stroke, as well as to determine its prognostic significance. </jats:sec

Review of Inge Nielsen, Cultic Theatres and Ritual Drama in American Journal of Archaeology, on-line reviews, Vol. 111.1:

Nielsen has done us a great service by collecting the considerable evidence for cultic performance spaces in Egypt, Mesopotamia, Syria, Phoenicia, Asia Minor, Crete, Greece, Sicily, and Italy. A table (340–41) gives an index of the 58 bestpreserved theaters, but dozens of others are discussed as well. Although some of the theaters could also have been used for “secular” literary drama, this volume focuses on cultic use. Nielsen’s observations should be of great interest to students of theater, religion, and ancient architecture

Propertius on the Site of Rome

The image of the site of Rome when it was hills, marshes and meadows, not yet spoiled by urban intrusion, was a favorite of Virgil and the Augustan elegists. In this paper I would like to examine the site as it appears in Propertius 4,1 ; 4,4 and 4,9. Although Propertius was following precendents from Tibullus 2,5 and Aeneid 8, his departures from the topography they mapped out need to be systematically examined. I will suggest (a) that Propertius generally offered a darker view of the site of Rome by endowing it with morally ambiguous qualities and by populating it with unappealing characters. Moreover (b) in fashioning this landscape Propertius settled on a view of the workings of nature -- consistent with other poems in Book 4 -- in which nature undermines human progress. This view of nature is further underscored by the suppression of the theme of the Golden Age

A Depiction of a Comic Mythological Burlesque?

A late eighteenth-century engraving is the only surviving record of a vase painting that shows a very odd scene, possibly reflecting a fifth- or fourth-century B.C. comedy