Wetting of crossed fibers: multiple steady states and symmetry breaking

We investigate the wetting properties of the simplest element of an array of random fibers: two rigid fibers crossing with an inclination angle and in contact with a droplet of a perfectly wetting liquid. We show experimentally that the liquid adopts different morphologies when the inclination angle is increased: a column shape, a mixed morphology state where a drop lies at the end of a column, or a drop centered at the node. An analytical model is provided that predicts the wetting length as well as the presence of a non-symmetric state in the mixed morphology regime. The model also highlights a symmetry breaking at the transition between the column state and the mixed morphology. The possibility to tune the morphology of the liquid could have important implications for drying processes

Real-Time Measurement of Myosin–Nucleotide Noncovalent Complexes by Electrospray Ionization Mass Spectrometry

AbstractNanoelectrospray ionization mass spectrometry has been used to measure the binding of ATP and ADP to the active site of rabbit skeletal myosin-S1. Increases in the molecular mass of myosin-S1 of 425±10Da were obtained with the binding of ADP to the active site and by 530±10Da with either ATP or hydrolysis products ADP and phosphate. Active site titrations of myosin-S1 with ADP gave a stoichiometry of ∼1 ADP/S1 with an affinity in the micromolar range. The binding of ATP to myosin-S1 could be observed in the presence of up to 60μM of excess MgATP without nonspecific binding of MgATP to the myosin. Conversion of the nucleotide complex containing an equilibrium mixture of ATP and ADP-Pi bound to myosin-S1 to one containing only bound ADP occurs at a rate consistent with that of the known steady-state rate of ATP hydrolysis. We expect this method to be of considerable use in the analysis of ligand binding and hydrolysis by the active sites of expressed myosin and myosin subfragments, which are not available in sufficient quantities for conventional methods of measurement of ligand binding

Presidents and the Rhetoric of Recessions

Are presidents reticent during recessions? Some research indicates that presidents make fewer major and minor speeches when economic conditions worsen (Ragsdale 1984; Eshbaugh-Soha 2010). We examine whether this holds true with major discretionary speeches utilizing recessions as the indicator of poor economic conditions. In addition, we also investigate the subject matter of major discretionary speeches given during both economic expansions and contractions. Presidents potentially have an incentive during a recession to focus the attention of the public away from economic concerns, where they have little command and control ability, to foreign policy, where they do have more power to act unilaterally. We find that presidents are not reticent during recessions. During recessions, fewer average months elapse between major discretionary speeches than we find elapse during economic expansions. Furthermore, while presidents never talk about the economy at high rates overall, they do focus more than twice as many major discretionary speeches on economic topics during recessions than they do during expansions. We also find no evidence that presidents attempt to ratchet up the rate at which they discuss foreign policy during recessions in an attempt to divert attention from economic matters

George W. Bush and the Rhetoric of Chief Legislator: The First Term

Near the beginning of a congressional session, the president will present key pieces of his legislative agenda to both Congress and the American public in the State of the Union address (SUA). He will couch his requests in a way that seeks to persuade his audiences he has the legislative solution to a problem he details. Effective political communication between the president and Congress is essential since each play key roles in the legislative process. While Congress comprises the legislative branch, the moniker we attach to one of the multiple jobs with which presidents are charged is that of chief legislator. Within the legislative process, presidents may recommend legislation, but it is up to Congress to act. While the chief legislator’s role is limited, the SUA has become a potent tool that the president may utilize in his role as chief legislator. Presidents, as chief legislators, share two goals with regular legislators. They desire to secure reelection, and they want to make public policy. In addition, term limited presidents have a unique goal; they want to secure a positive legacy. In the SUA, chief legislators will claim credit for past successes, make requests for legislative actions, and use symbols all to further these mutually reinforcing goals. We examine how President George W. Bush used the rhetoric of the SUA in his role as chief legislator during his first term to aid him in the advancement of these goals. We find that Bush’s use of the policymaking rhetoric changed after 9-11 and became unusual when compared to previous presidents’ use of the SUA. He acted less as chief legislator and more as commander-in-chief and chief executive

Communicating as Chief Legislator: Four Case Studies from the State of the Union

While the Constitution stipulates in Article II, Sec. 3 that presidents can recommend necessary and expedient measures to Congress, it is up to Congress to act. The primary place presidents engage in the activity of recommending legislation is the State of the Union Address (SUA). We examine SUAs from 1965-2002 and identify the legislative requests that presidents make of Congress. The SUA is a unique presidential speech that allows assessment and comparison between presidents of whether Congress follows where the president leads. Are presidents successful in getting Congress to enact the policies they ask for in the SUA? Furthermore, the policy making environment is complex and in order to assess the nature and role of the chief legislator’s communications with Congress in the SUA, we utilize case studies to determine what role the SUA played in the outcome of four cases. Each case was chosen based on its outcome. One is an unsuccessful request (constitutional amendment for four-year house terms), one is fully successful (authorization and funding of a manned space station), one is partially successful (civil service reform), and one is a repeat request from multiple presidents that was eventually successful (line-item veto). We find that when a president uses the SUA to request action of Congress, he typically receives about two in five of his requests, either in full or in part, during the following congressional session. In each of our four cases, the SUA played an integral role in the outcome, although this did not always mean the president was successful in getting his request enacted, or that the SUA was the most important factor. The SUA is an excellent tool of political communication for the chief legislator, but it is not without its limitations. The chief legislator’s position in the political system makes it much more likely Congress will give consideration to his requests, but it does not guarantee the president will receive a substantial amount of his requests. The chief legislator’s increase in rhetorical powers represented in the SUA did give him an advantage over regular legislators, but it did not unduly increase his power over the legislature. The chief legislator is not an ordinary legislator, but neither is he empowered with a rhetorical arsenal with which he can assault Congress. The system of shared legislative powers continues to check the president despite an increase in the president’s rhetorical power. The SUA is a tool the chief legislator can utilize to facilitate congressional leadership, but it is not a weapon with which he can cudgel Congress into accepting his leadership

The Presidential Rhetoric of Hard Times

Is there a presidential rhetoric of hard times? We are interested in presidents’ rhetorical reactions during economic contractions. Do they rhetorically react at all? If they choose to speak, what do they seek to convey to the public about the economy? We analyze the major discretionary speeches presidents give during recessions. Some presidents are reluctant to address major economic remarks to the public; in five of the 11 recessions since World War II, presidents have not offered a major economic speech. They do, however, deliver major discretionary speeches on other topics during recessions. While most presidents tend to deliver more major remarks about non-economic subjects during recessions, Reagan is a notable exception. When presidents do choose to direct major remarks on the economy, we search for common characteristics in their rhetoric to examine if this subset of speeches classifies as a genre of rhetoric. We examine three dimensions in the speeches: orientation toward time, the tone of the remarks, and whether or not there is action specified. We found that there is no discernable overall pattern for how presidents orient their rhetoric in time, the speeches are more negative in tone than expected, and while there are a good number of action oriented sentences, the speeches are not uniformly action oriented. Thus, there is not sufficient evidence to suggest there is a uniform presidential rhetoric of hard times

The Pedagogical Value of Polling: A Coordinated 2012 Exit Poll Project Across Diverse Classrooms

Several previous studies have demonstrated that student exit polling has educational value and promotes civic engagement (Berry and Robinson 2012, Evans and Lagergren 2007, Lelieveldt and Rossen 2009, and others). The authors of this paper have created assignments and an instructor\u27s manual on running student exit polls in undergraduate courses. Three institutions used these assignments during the fall 2012 semester. Working together, these instructors created an opportunity for their students to participate collaboratively with others in survey design and data analysis. This effort further provided assessment data on the effectiveness of this pedagogical approach for student engagement outside of the classroom in different communities and course contexts. Student surveys measured the impact that this experience had on their understanding of their own community, their relationship to the national community, their understanding of survey methodology, and descriptive statistics. Do students learn more about their community or the scientific process? Does it matter whether the course is designed primarily around politics, statistics, or public opinion? This paper addresses these questions and how these effects vary across different types of students and classrooms

Descriptions of African Diptera

16 p. ; 24 cm.Includes bibliographical references

Redesigning the Warren Animal Shelter

The new shelter should incorporate improved natural lighting and ventilation, adequate space for laundry facilities and more space for the animals\u27 living and bathing needs. The design should consider how to prevent dogs from barking and disturbing one another while in the kennels. Increased storage is necessary for the animal shelter to contain the food and living amenities for the incoming animals

School Playground Surfacing and Arm Fractures in Children: A Cluster Randomized Trial Comparing Sand to Wood Chip Surfaces

In a randomized trial of elementary schools in Toronto, Andrew Howard and colleagues show that granitic sand playground surfaces reduce the risk of arm fractures from playground falls when compared with wood fiber surfaces