4,125 research outputs found
Attention to attributes and objects in working memory
No full textIt has been debated on the basis of change-detection procedures whether visual working memory is limited by the number of objects, task-relevant attributes within those objects, or bindings between attributes. This debate, however, has been hampered by several limitations, including the use of conditions that vary between studies and the absence of appropriate mathematical models to estimate the number of items in working memory in different stimulus conditions. We reexamined working memory limits in 2 experiments with a wide array of conditions involving color and shape attributes, relying on a set of new models to fit various stimulus situations. In Experiment 2, a new procedure allowed identical retrieval conditions across different conditions of attention at encoding. The results show that multiple attributes compete for attention, but that retaining the binding between attributes is accomplished only by retaining the attributes themselves. We propose a theoretical account in which a fixed object capacity limit contains within it the possibility of the incomplete retention of object attributes, depending on the direction of attention.</p
Properties of the plasma membrane H+-ATPase from the stele and cortex of Zea mays roots
No full textPlasma membranes of high purity, as assayed by marker enzymes, were obtained by phase partitioning from stele and cortex tissues of Zea mays (cv LG11) roots. ATP hydrolytic activities in the stele and cortex plasma membrane fractions were inhibited by vanadate, SW26 and erythrosin B, but insensitive to nitrate. Activity in both fractions exhibited a marked pH optimum of 6.5 and displayed typical Michelis-Menten kinetics. A high substrate specificity was apparent in both the stele and cortex plasma membrane fractions, while the lower fractions, after phase partitioning, showed less specificity for nucleotide substrates. Specific activities of the stele (67.8 jimol Pi mg"1 h~l) and cortex (78.4 fimol Pi mg-1 h-1) plasma membrane H+-ATPase were found to be very similar.Proton pumping activities in microsomal membrane fractions from stele and cortex were inhibited by nitrate and insensitive to vanadate. Ho-mogenization of stele and cortex tissue in the presence of 250 mol m~s KI resulted in microsomal fractions exhibiting vanadate-sensitive, nitrate-insensitive proton pumping activity, suggesting a plasma membrane origin for this activity. SW26 was also an effective inhibitor of proton pumping activity, although results indicated an interaction between SW26 and the fluorescent probes quinacrine and acridinc orange.Xylem perfusion of intact maize roots with various inhibitors of the plasma membrane H+-ATPase decreased the roots' ability to regulate the pH of the xylem sap, while perfusion with fusicoccin initiated a marked decrease in the pH of the xylem sap.The effects of fixatives routinely used in histochemical studies of ATPase activity were also examined. ATPase activity in both microsomal and plasma membrane fractions was inhibited by the fixatives glutaraldehyde and formaldehyde. Addition of ATP during the incubation step or during the fixation procedure decreased the degree of ATPase inhibition suggesting a substrate protection mechanism in operation.Analysis of the lipid and sterol content of the stele and cortex plasma membranes revealed that the major sterol present in both was stigmasterol which was found in significantly higher quantities in the cortex (27.4 /ig~l compared to 17.4 fig, mg"1), the other sterols detected were cholesterol, campesterol and sitosterol. The major lipids were phosphatidylcholine (PC) and phosphatidylethanolamine (PE) with PC more abundant in the stele (88.9 /ig mg~r) than in the cortex (59.0 fig mg"1); levels of PE were similar in both tissues.</p
Letter - Andrew Cowan to William Cowan
No full textA letter from Andrew Cowan to his son William Cowan 29 Septemer 1841. The letter reads "Dear William, I have taken my pen the third time since I have received any word from you, my first letter was about the beginning of the year, and the second in the month of April with John Armstrong of Northhouse, he sailed from Liverpool the fifteen of that month with his sisters Jane and Jenny and their two children. I received a letter from him dated Cleavland in the State of Ohio the 6 of June. He did not intend stopping in that place. The leaves us all well for any thing that I know, but I have not heard from Andrew since March altho I have writen to him three months since your Mother and I are both sore faild altho we have tolerable good health for which we desire to be thankfull to the giver of all our mercies, which are new every day, that we may be found in Christs and clothed in his imputed righteousness at the last, for in him is only found true happyness. We have had another cold wet Summer and the crops is far back ------ not light, the price of -----is high and trade bad, but sheep and cattle are high. Cattle have not been higher since the French war, but the cattle trade is very bad at present and the opperatives out of imployment and consequently verrry badly of. If none of my former letters have reached you this will inform you that James is at Lanshawburn, and gets imployment all the year, he keeps a cow and five or six sheep, they have three children, Mary, Hannah, and Andrew; I was there after clipping time seeing them, they seem to be verry happy. James Lamb is well he was here the other night, he has got two letters from his son Adam this Summer; they are still in the same place and will finish their job this fall, and seem to be doing well, your Uncle Adam Scott and family are well. John was there lately there is little prospect of his getting to America as the money that was left him is not got yet and will not for some time, If ever this reach you, you must let us know how all the Scotch people that are near you, that went from this place of the Country are doing, as their freinds are anxious to hear from them, perticularly if you know what is becomed of Alexander Hoggs widow and family of ------hill, as I was desired to write to you about them - I got a letter from John Miller dated Gatt but I understand it is a long way from your place he was a gentleman and had the charge of a farm and seems verry ----- Now William if this ever reach you, you must excuse me for not filling this letter up, but if I receive an answer I promise to fill the next better, We all join in our love and respect to you and family. From your loving Father Andrew Cowa
AWARD-WINNING AUTHOR, PHYSICIAN TO PRESENT COWAN MEMORIAL LECTURES AT U MEDICAL SCHOOL
No full textAWARD-WINNING AUTHOR, PHYSICIAN TO PRESENT COWAN MEMORIAL LECTURES AT U MEDICAL SCHOO
Models of verbal working memory capacity: What does it take to make them work?
No full textTheories of working memory (WM) capacity limits will be more useful when we know what aspects of performance are governed by the limits and what aspects are governed by other memory mechanisms. Whereas considerable progress has been made on models of WM capacity limits for visual arrays of separate objects, less progress has been made in understanding verbal materials, especially when words are mentally combined to form multiword units or chunks. Toward a more comprehensive theory of capacity limits, we examined models of forced-choice recognition of words within printed lists, using materials designed to produce multiword chunks in memory (e.g., leather brief case). Several simple models were tested against data from a variety of list lengths and potential chunk sizes, with test conditions that only imperfectly elicited the interword associations. According to the most successful model, participants retained about 3 chunks on average in a capacity-limited region of WM, with some chunks being only subsets of the presented associative information (e.g., leather brief case retained with leather as one chunk and brief case as another). The addition to the model of an activated long-term memory component unlimited in capacity was needed. A fixed-capacity limit appears critical to account for immediate verbal recognition and other forms of WM. We advance a model-based approach that allows capacity to be assessed despite other important processing contributions. Starting with a psychological-process model of WM capacity developed to understand visual arrays, we arrive at a more unified and complete model.</p
RISE and Shine: How Jefferson Health’s Peer Support Program Improves Care for All
No full textEvidence suggests that providing psychological support to caregivers can make care safer. Such is the basis for Jefferson Health’s RISE program: peer-to-peer mentoring for providers involved in patient harm. Program leads, John Olsen and Dr. Scott Cowan, sat down with Patient Safety managing editor, Caitlyn Allen, to discuss the program’s genesis, the positive impact it’s had on staff, and how the program can be replicated in other institutions
Useful animation: iconography, infrastructure, and impact
No full textThis article defines and explores the history of ‘useful animation’. Animation has found frequent application as a powerful practical and conceptual tool in professional fields requiring a versatile instrument for a variety of representational needs, from science and medicine to education and advertising. Today, forms of useful animation populate our television news, social media, and urban environments in ways that are no less consequential for their having become second nature. But how did we get here? This tradition is distinct from entertainment or art, and investigating this requires a revision of existing animation history, prompting new research questions and methodologies. This article presents such a framework for further work in this field. In doing so, it has three main aims. First, we establish the intellectual context and consider the historiographic implications of prior research in this area. Second, we ask three key theoretical research questions that can guide the investigation of the history of useful animation (How did useful animation build upon existing graphic traditions? What were the professional and institutional contexts for useful animation and how did these develop? What impact did animation have on professional fields and their understanding of the world?) Finally, we present three case studies from the first decades of film history that illustrate how these questions can be answered and suggest methods and research resources available to scholars of useful animation. These address Jean Comandon’s public health films in Post-WWI France, animated maps made by the Austro-German Institut für Kulturforschung in the inter-war period, and the animated film Unemployment and Money made in Britain illustrating Michael Polanyi’s economic theories in the 1930s. This article provides a basis for future research into this topic
RABBI HAROLD S. KUSHNER, AUTHOR, TO DELIVER U OF U COWAN LECTURE
No full textHarold S. Kushner, author of the best-selling When Bad Things Happen to Good People, will deliver the annual Max P. Cowan Memorial Lecture on Humanistic Medicine in the auditorium of Primary Children\u27s Medical Center, 320 East 12th Avenue, on April 19, 1990, at 8 a.m. His topic will be "What Patients Tell Me That They Won\u27t Tell Their Doctors.
Recommended from our members
UNT Special Collections Artifact Photography
No full textPhotograph of the cover of "Somewhere in France: And Other Poems" by Ella F. Cowan, held by UNT Special Collections. The grey textured cover has the title and author stamped on the front at the top
Henri Temianka Correspondence; (cowan)
No full textThis collection contains material pertaining to the life, career, and activities of Henri Temianka, violin virtuoso, conductor, music teacher, and author. Materials include correspondence, concert programs and flyers, music scores, photographs, and books.https://digitalcommons.chapman.edu/temianka_correspondence/1778/thumbnail.jp
- …
