bluuebunny/crossref_metadata_2025 huggingface dataset:
The transitions and melting behavior of thermally crystallized poly(ethylene terephthalate) and their correlations with ftir and density measurements
Authors: Lin Shaow‐Burn , Koenig Jack L.
Published: June 2010

The transitions and melting behavior of thermally crystallized poly(ethylene terephthalate) (PET) are studied using a computerized differential scanning calorimeter (DSC). A transition occurs from a structural stage characterized by a strong glass transition and an exothermic crystallization peak to a stage with a barely perceptible glass transition and an endothermic low melting (LM) peak in the DSC thermograms. This transition corresponds to the change from the primary to secondary crystallization process of PET. The exothermic crystallization peak is only observed within the primary crystallization stage. The maximum temperature of the LM peak is a function of annealing temperature and time, and depends on the microstructure of the imperfectly formed crystallites. The high melting peak is the melting of crystallites of higher perfection and is influenced by the recrystallization process of the sample during the scan.
Stereoselective hydrolysis of amino acid esters by modified polyethylenimines: Effects of quaternization of polymer and of added surfactants
Authors: Kimura Yoshiharu , Nango Mamoru , Kuroki Nobuhiko , Ihara Yasuji , Klotz Irving M.
Published: June 2010

Quaternized polyethylenimines exhibit viscosity behavior very similar to that of linear flexible polyelectrolytes and thus evidently swell in dilute salt solutions. This swelling is manifested also in the rate constants for the hydrolysis of chiral or achiral nitrophenyl esters catalyzed by these polymers. Stereoselective preference is exhibited in hydrolyses catalyzed by the quaternized polymers containing covalently linked l‐histidine moieties. Maximum stereoselectivity is manifested at polymer concentrations corresponding to nonswollen conformations. With added cetyltrimethylammonium bromide, the stereoselective preference of the catalyzing polymer can be reversed. A comparison of the effects of added anionic, nonionic, and cationic detergents shows decreases in rate for the first, no significant effect for the second, and substantial changes for the third, depending on the polymer and detergent concentrations. Cationic detergents of different chain lengths and structures show different effects reflecting largely their extent of binding by the polymer.
Estimating reactivity in free radical copolymerizations
Authors: Laurier G. C. , O'Driscoll K. F. , Reilly P. M.
Published: June 2010

Given good reactivity ratio data for free radical vinyl copolymerizations, the use of the Alfrey—Price Q—e scheme permits the assignment of reactivity parameter values for individual monomers and the prediction of unknown reactivity ratios. A new, statistically based method has been developed and tested on a set of 11 monomers to estimate Q–e values for those monomers. The results of these estimates suggest that if care is exercised in the selection of monomer pairs for use in Q–e determinations, the Q–e scheme is quite reliable for reactivity ratio prediction on many monomer pairs.
Polycondensation of carboxylic acids and carbinols in aqueous emulsion
Authors: Baile Madhu , Chou Yungnien J. , Saam John C.
Published: June 2010

Water‐insoluble diols and dicarboxylic acids condense to polyesters in aqueous emulsion under relatively mild conditions in the presence of sulfonic acids. Azelaic acid and 1,10‐decanediol give conversions to polymer of 50% and 75%. Molecular weights range between 1500 and 3000. The best catalysts are sulfuric acid or the sulfonic acid surfactants. Water soluble monomers give little or no increase in molecular weight. Estimates based on equilibrium constants for a typical esterification, and the observed molecular weights indicate that only minute amounts of water can be present at the site of reaction. It is suggested that the process might be related at least in some aspects to the condensation polymerization of silanol‐ended polydimethylsiloxane oligomers in emulsion [1].
Turner alfrey and hollow‐fiber membrane technology
Authors: Davis T. E. , Heitz R. G.
Published: June 2010

Membranes in the form of hollow fibers are increasingly being used for processes such as desalination, hemodialysis, and recovery of various gases. Turner Alfrey played a crucial role in the birth of this new technology: (1) He selected and taught the necessary fundamentals of polymer science to the researchers trying to make this new idea work. (2) He actively encouraged the researchers and their financial supporters by his clear understanding of the soundness and the potential of this new engineering tool. (3) He even demonstated how to tailor the properties of a polymer to the task at hand by his own elegant laboratory experiments.
Mechanism of emulsion polymerization
Authors: Vanderhoff John W.
Published: June 2010

Both conventional and inverse emulsion polymerization comprise the emulsification of an immiscible monomer in a continuous medium followed by polymerization with a free radical initiator to give a colloidal sol of polymer particles. Both processes give “emulsion polymerization kinetics,” i.e., a proportionality of both the polymerization rate and polymer molecular weight to the number of particles instead of the inverse relationship between rate and molecular weight observed for mass, solution, and suspension polymerization. The emulsion polymerization process can be divided into particle nucleation and particle growth stages and can be carried out using batch, semicontinuous, or continuous processes. Seeded emulsion polymerization can be used to avoid the particle nucleation stage in all three processes. The many mechanisms proposed for the initiation of emulsion polymerization can be divided into four categories according to the locus of particle initiation: (i) monomer‐swollen micelles; (ii) adsorbed emulsifier layer; (iii) aqueous phase; (iv) monomer droplets. These general principles are applied to: (i) the preparation of monodisperse latexes by seeded emulsion polymerization; (ii) the locus of particle initiation for various monomers and initiators; (iii) emulsion copolymerization; (iv) core‐shell emulsion copolymerization; (v) polymerization in fine monomer droplets; (vi) inverse emulsion polymerization.
Preparation and application of monodisperse polymer particles
Authors: Ugelstad J. , Mfutakamba H. R. , Mørk P. C. , Ellingsen T. , Berge A. , Schmid R. , Holm L. , Jørgedal A. , Hansen F. K. , Nustad K.
Published: June 2010

The swelling capacity of aqueous dispersions of particles (or droplets) containing a relatively low molecular weight, highly water‐insoluble compound (Y) may be more than a thousand times higher than that of particles consisting of polymer only. The rate, and also the degree of swelling, may furthermore be increased by having the swelling substance, which usually is a low molecular weight, slightly water soluble substance, present in a finely dispersed form. A two‐step swelling process has been described. In a first step, relatively small monodisperse polymer particles are swollen with a component Y and then with monomer or monomer mixtures, followed by polymerization. The method allows preparation of highly monodisperse particles of more than 50 μm diameter with a standard deviation of less than 2%. The particles may be prepared as core and shell particles of different density and with various surface layers, or as macroporous particles. The new particles have found application as standards in immunoassays and, most important up to now, in liquid chromatography. An extension of the process allows the production of monodisperse magnetizable particles which have found application in cell separation of cancer cells from normal cells.
Dynamics of conformational transitions in polymers
Authors: Helfand Eugene
Published: June 2010

A review is presented of research on several aspects of the dynamics of conformational transitions in polymers. Brownian dynamics computer simulations of polymer chains show that transitions occur frequently in a correlated fashion involving cranklike counterrotation of two parallel bonds. Theoretical analysis brings out the importance of such counterrotations in creating a localized mode by which the transition can proceed without excessive motion of the whole molecule. The correlated motions are reflected in time correlation functions, which take on a character reflecting diffusion of the information about the initial state. Finally, several experiments are cited that can be explained on the basis of this picture of the mechanism of con formation a! transitions.
Effect of chain flexibility on the dynamics of rodlikk polymers in the entangled state
Authors: Doi Masao
Published: June 2010

The Brownian motion of semiflexible polymers in networks and in concentrated solutions is discussed. If the polymer is assumed to move only along itself by reptation, various time correlation functions are calculated rigorously. The results show that the Brownian motion is independent of the mesh size a over a wide range. It is then argued that the observed rodlike behavior of semiflexible polymers in concentrated solutions is due to the rapid bending fluctuation of the polymer.
Molecular theory expressions for the stress tensor in flowing polymeric liquids
Authors: Bird R. Byron , Curtiss C. F.
Published: June 2010

Various molecular expressions for the stress tensor for polymeric liquids are given and interrelated. Particular attention is paid to restrictions associated with constraints in the molecular models, hydrodynamic interaction, and molecular confinement in concentrated systems. A recently derived generalization of the Kramers‐Kirkwood stress‐tensor formula can be taken as the starting point for many polymer calculations.
Details of phase separation processes in polymer blends
Authors: Snyder H. L. , Meakin P.
Published: June 2010

We have investigated the details of phase separation dynamics in high‐molecular‐weight (polystyrene‐PVME) polymer blends utilizing small angle light scattering techniques and have compared our results with the various theories, computer simulations, and phase separation dynamics in small molecule systems. Although linearized theories are consistent with many qualitative features of phase separation dynamics, they fail to provide quantitative accuracy. It appears that both nonlinear terms and hydrodynamic effects must be included to provide a quantitative description. Quantitative agreement between phase separation dynamics in small molecule systems and high‐molecular‐weight polymer blends is also reported.
Raumfachwerke und kein Ende?
Authors: Klimke Herbert , Walochnik Wolfgang
Published: June 2010

Dieser Beitrag gibt einen Überblick über die Entwicklung des Bauens mit räumlichen Stabwerken in einer Periode von etwa 30 Jahren, von der Teilüberdachung des Berliner Olympiastadions 1974 bis zum Glasdach des Berliner Hauptbahnhofs 2004. In dieser Zeit hat sich die Technologie von der ebenen Raumfachwerkplatte bis zu den leichten Stützkonstruktionen für den Glasbau mit Zugstangen und Seilen weiterentwickelt. Die kennzeichnenden Projekte dieser für das Bauwesen stürmischen Entwicklung werden mit einigen Überlegungen zum Entwurfsprozess beispielhaft vorgestellt.

Space trusses and no end? This paper offers a short review of the development in the field of space trusses for a period of about 30 years, beginning with the partial roof structures of the Olympiastadion Berlin in 1974 until the glass cover for the Berlin Hauptbahnhof (main station) in 2004/2006. During this period the technology has developed from the plane space trusses to the light weight spatial structures for glazed buildings, incorporating tension rods and cables as structural elements. The marking projects of this exiting development are exemplarily presented together with some reflections on the structural design process.
In situ observations of Stygiomedusa gigantea in the Gulf of Mexico with a review of its global distribution and habitat
Authors: Benfield Mark C. , Graham William M.
Published: June 2010

Four individuals of the large scyphozoan jellyfish Stygiomedusa gigantea were observed in the northern Gulf of Mexico over 2005–2009 by industrial remotely operated vehicles as part of the SERPENT Project. One of these observations included the symbiotic bythitid fish Thalassobathia pelagica. Prior to these observations, neither S. gigantea nor T. pelagica had been observed in, or collected from the Gulf of Mexico. In order to summarize the available information on S. gigantea, we located 110 observations obtained over 110 years (1899–2009) representing 118 individual specimens of this species from around the world. The resulting dataset confirms that this species is cosmopolitan occurring with records from all oceans except the Arctic. While the depth-range of the four Gulf of Mexico specimens was bathypelagic, there appears to be a pattern of S. gigantea occurring in mesopelagic and epipelagic depth-zones at high latitudes, particularly in the Southern Ocean and mesopelagic and bathypelagic depths at mid- and low-latitudes. This pattern may be related to the meridional vertical distribution of temperature or perhaps avoidance of light levels that could degrade porphyrin pigments. There was no evidence that this species migrates vertically. Two of the individuals in the Gulf of Mexico appeared to be actively clinging to subsea structures and we speculate that this is a consequence of its normal mode of feeding, which may entail using its large oral lobes to hold on to, and trap prey.
Effects of time since urbanization on anuran community composition in remnant urban ponds
Authors: GAGNÉ SARA A. , FAHRIG LENORE
Published: June 2010

Low-density residential development, the fastest growing land use in the USA, is increasingly occurring adjacent to protected areas and in areas of high biodiversity. Thus, determining the environmental impacts, including the cumulative impacts, of proposed residential developments is a pressing challenge. The relative abundance and species richness of anurans in 19 ponds surrounded by landscapes with varying ages of residential development were measured, while endeavouring to control for local habitat quality effects on the anurans. Age of residential development was a predictor in the best models describing the responses of four individual anuran species and total anuran relative abundance. In particular, all of the best models of gray treefrog Hyla versicolor relative abundance included age of residential development as a predictor. Present-day anuran communities in remnant urban ponds are evidently responding to the effects of residential development that occurred up to 54 years in the past.
The Liberty of the Church and the Road to Runnymede: John of Salisbury and the Intellectual Foundations of the Magna Carta
Authors: Nederman Cary J.
Published: June 2010

Scholars generally agree that the Magna Carta of 1215 was a watershed in Western (and, more specifically, English) legal and political history and thought. Beyond this simple statement, however, there is little consensus concerning the nature and significance of the Magna Carta's achievement. One central unresolved issue centers on whether the charter represents a principled defense of human liberty or instead reflects a pragmatic statement of baronial liberties. The dispute over this question is nontrivial and reflects much more than a matter of language. If one subscribes to the former belief, which received its classic articulation in the seventeenth century (Turner 2003, 145–82) and retains powerful resonance today (Linebaugh 2008), then the Magna Carta deserves to be accorded a foundational role in the intellectual and political history of the liberal-democratic constitutional tradition, in which the rule of law is deemed the basis for the protection of individual freedom. If, however, one adopts the viewpoint of “the modern historian” that the charter “is a statement of [specific] liberties rather than an assertion of [general] liberty,” then the document should be read narrowly as an interesting artifact stipulating elite “privileges” that were “devised mainly in the interests of the aristocracy” (Holt 1965, 4). In other words, either the Magna Carta reflects deeper philosophical doctrines and commitments that enjoy purchase beyond their specific time and place, or it represents an expression of the immediate demands and grievances of a specific class displeased with the conduct of King John's government.
Jus Tempus in the Magna Carta: The Sovereignty of Time in Modern Politics and Citizenship
Authors: Cohen Elizabeth F.
Published: June 2010

In the English constitutional tradition, subjecthood has been primarily derived from two circumstances: place of birth and time of birth. People not born in the right place and at the right time are not considered subjects. What political status they hold varies and depends largely on the political history of the territory in which they reside at the exact time of their birth. A genealogy of early modern British subjecthood reveals that law based on dates and temporal durations—what I will call collectively jus tempus—creates sovereign boundaries as powerful as territorial borders or bloodlines. This concept has myriad implications for how citizenship comes to be institutionalized in modern politics. In this article, I briefly outline one route through which jus tempus became a constitutive principle within the Anglo-American tradition of citizenship and how this concept works with other principles of membership to create subtle gradations of semi-citizenship beyond the binary of subject and alien. I illustrate two main points about jus tempus: first, how specific dates create sovereign boundaries among people and second, how durational time takes on an abstract value in politics that allows certain kinds of attributes, actions, and relationships to be translated into rights-bearing political statuses. I conclude with some remarks about how, once established, the principle of jus tempus is applied in a diverse array of political contexts.
Ready to Lead on Day One: Predicting Presidential Greatness from Political Experience
Authors: Balz John
Published: June 2010

Presidential candidates frequently tout their political experience on the campaign trail, telling voters that it has prepared them to deal with complex problems, make weighty decisions, and show leadership. The value of that argument was put to the test in the 2008 presidential campaign by Hillary Clinton against her opponent, Barack Obama. This paper uses a multilevel model to analyze the value of national and state political experience on overall presidential greatness, as judged by seven surveys of academic experts. Overall, there is no evidence that political experience improves the likelihood of strong presidential performance, and even some weak evidence that political experience in certain political positions, most notably mayor and member of Congress, leads to poorer performance. In the end, great presidents are not great simply because they have spent their lives in politics and learned important lessons. Other personal and historical factors are likely to be more important.
Scholarly Productivity in Non-Ph.D. Departments
Authors: Collins Todd A. , Cooper Christopher A. , Knotts H. Gibbs
Published: June 2010

Political scientists hail from large, research-intensive universities like the Ohio State University, regional comprehensive schools like Western Kentucky University, and small teaching-intensive institutions like Mars Hill College. Despite this diversity, most studies of the political science discipline overlook the contributions of individuals from non-Ph.D. departments. To address this oversight, we compare the publishing rates of scholars with four types of affiliations: non-Ph.D. departments, Ph.D. departments, non-U.S. departments, and nonacademic institutions. We focus particularly on whether faculty from non-Ph.D. departments publish in different types of journals than faculty from other departments, and whether the institutional affiliations of editorial board members corresponds to the institutional affiliations of published authors. We find that people from non-Ph.D. departments represent 16% of the authors in our sample of political science journals, and their contributions are particularly noteworthy in certain types of journals. We also demonstrate that the institutions represented on editorial boards generally do not reflect the institutional affiliations of the authors who publish in these journals.
Service Learning and Simulations
Authors: Jenkins Shannon
Published: June 2010

Both service learning and simulations have been shown to positively impact student outcomes, but they are not often used together. This article examines how to effectively combine these active learning styles to reap the benefits of both. After examining a case in which the two were combined and the impact this approach had on student evaluations and learning outcomes, I discuss how such projects can be successfully executed in a variety of other classes.
Graduate Students as Independent Instructors: Seven Things to Know about Teaching Your Own Course while in Graduate School
Authors: Burmila Edward M.
Published: June 2010

Despite being responsible for a large percentage of undergraduate instruction, graduate students often receive little preparation for their first solo teaching assignments (J. D. Nyquist et al., Change 31 (3): 18, 1999). Furthermore, the existing literature on pedagogy fails to address the unique challenges faced by graduate students who are asked to serve as course instructors rather than teaching assistants. This article presents seven pieces of advice intended to better prepare the predoctoral graduate student to assume the role of the professor before assuming the title. By understanding the attitudes of undergraduate students toward graduate instructors, preparing in advance to handle the mistakes that novice teachers often make, and recognizing the correlation between outward confidence and student perceptions of instructor quality, graduate students can derive the most benefit from a stressful and time-consuming assignment. Most important, graduate instructors can learn to effectively manage the time spent on teaching duties to ensure that other responsibilities such as coursework, qualifying exams, and dissertation research do not suffer.
Pop Culture in the Classroom: American Idol, Karl Marx, and Alexis de Tocqueville
Authors: Centellas Miguel
Published: June 2010

This article discusses the use of pop culture in the classroom as a means to teach foundational political science authors and concepts. I focus on my experience using American Idol as a point of reference to discuss Marx and Engel's The Communist Manifesto and Tocqueville's Democracy in America in undergraduate comparative politics courses. Students are asked to construct a written argument projecting Marx or Tocqueville's perceptions of American Idol, based on their readings. My experiences demonstrate that asking students to reflect on their own contemporary experience through the prism of these two works helps them in three ways: (1) to better understand the ideas of Marx and Tocqueville, as well as their differences; (2) to develop an appreciation for the continued relevance of works in the discipline's canon; and (3) to sharpen and develop critical thinking and analytical skills.
MALCOLM EDWIN JEWELL
Authors: Canon Bradley C.
Published: June 2010

Malcolm “Mac” Jewell was a mainstay of the Political Science Department at the University of Kentucky (UK) for 36 years. For that same period and even longer, he was one of the profession's leading researchers in explaining legislative behavior (particularly in the states) and how state political parties worked. Mac retired from UK in 1994 but continued being active in our profession. Around 2004, he began suffering from Alzheimer's disease. He died on February 24, 2010, in Fairfield, Connecticut.
ROBERT H. SALISBURY
Authors: Heinz Jack
Published: June 2010

Bob was the Sidney W. Souers Professor Emeritus at Washington University, where he chaired the political science department both early and late in his career. He served as vice president of the APSA, president of the Midwest Political Science Association, and president of the Missouri Political Science Association, and he had been a Guggenheim Fellow and a Rockefeller Center scholar. He had been confined to his home by breathing problems in recent years, but he remained engaged and intellectually active. In his last months, Bob completed a new essay about interest groups, which is scheduled for publication soon. He died on April 9.
LEE SIGELMAN
Authors: Deering Christopher J. , Maltzman Forrest
Published: June 2010

On September 27, 2007, Lee Sigelman sent an e-mail message to a large number of coauthors, friends, and colleagues. The message began: “Friends: I'm sorry to burden you with the news that follows …” What followed was Lee's report that earlier in the day, he had received a diagnosis of stage IV colon cancer, that it had spread beyond the colon, and that he had six to twelve months (soon revised upward to almost two years) to live. For the next 27 months, Lee taught his colleagues and friends about how to approach both life and death.
TRUMAN DAVID WOOD
Authors: Kunkel Joseph A.
Published: June 2010

Truman David Wood graduated from Delevan (Minnesota) High School in 1950. He earned his bachelor's degree in political science from Mankato State Teachers' College (later Minnesota State University, Mankato). He worked as a teacher in several high schools in Iowa and Minnesota. He earned a master's and Ph.D. from the University of Iowa. He was a professor in the political science/law enforcement department of Mankato State University (now known as Minnesota State University, Mankato) from 1961 to 1991. He taught a variety of courses, but primarily focused on American political thought. Wood demonstrated great care for his students and understood quality teaching and careful advising to be the top priorities of his academic career. He was a leader in his department and the university for many years. He was particularly active in community service. He was a member of the Mankato Housing and Redevelopment Authority, the Mankato Planning Commission for 22 years, and chair of his church administrative council for 14 years. He frequently served as a public speaker for high school commencements and service clubs, and as an election analyst. He was active in Republican party politics until the 1980s, serving as a delegate to the National Convention in 1964. When he retired, he and his wife Reta established the Wood Scholarship for political science majors who demonstrate a record of community involvement and academic excellence. Truman Wood was an inspiring teacher, a caring advisor, and a model citizen. He shaped and touched many lives.
LEARNING RACE, SOCIALIZING BLACKNESS
Authors: Nunnally Shayla C.
Published: June 2010

Contemporary discourse about Black Americans questions the loyalties of younger Blacks to the advancement of the Black racial group. This discourse often compares the commitment of Black Americans who came of age during the Civil Rights Movement era to those who came of age during the post-Civil Rights Movement era. Fueling this discourse is a working assumption that somehow younger Black Americans have a different understanding about race and its role in Blacks' political interests. This begs the question whether there are generational differences in the ways that Black Americans learn about race, or racial socialization, perhaps with implications for distinct value orientations about Black politics. Using public opinion data from an original survey, the 2007 National Politics and Socialization Survey (NPSS), this paper compares the racial socialization experiences of four generations of Black Americans—(1) World War II generation (age 67 and older, born in and before 1940); (2) civil rights generation (ages 54–66, born 1953–1941); (3) mid-civil rights generation (ages 43–53, born 1964–1954); and (4) post-civil rights generation Black Americans (age 42 and under, born 1965 and after). Results of ordered probit regression analyses indicate minimal generational differences. Differences emerge in emphases on racial socialization messages about Black public behavior, Black intraracial relations, Black interracial relations, and composite factor loadings of Black consciousness and Black protectiveness messages.
RATS, RANDOM RETRIBUTION, AND REVOLUTION
Authors: Ossei-Owusu Shaun
Published: June 2010

The abysmal state of the American criminal justice system and its pernicious features has been well documented in much of the relevant literature. Feeley and Simon (1992) propose the notion of a “new penology” that prioritizes efficient, cost-effective (and often actuarial) techniques to manage criminal populations, while Katherine Beckett (1997) argues that the punitive shift in crime control policy was an ideologically motivated response to the Civil Rights Movement, with political rhetoric fomenting fears of crime and public policy reflecting the vogue of law-and-order punishment. David Garland's (2001) comparative study of the United States and Britain suggests that “late modernity,” which encompasses much of the social, economic, cultural, and technological advancements and changes of the second half of the twentieth century (e.g. wage stagnation, regressive tax policies, suburbanization, the rise in the service economy, new penal technologies), along with neoconservative politics in the 1980s played key roles in the reconfiguration of the criminal justice system.
NOTE ON MULTIPLE REVIEWS
Authors: Forman Tyrone A.
Published: June 2010

As readers of the Du Bois Review: Social Science Research on Race are well aware, this journal aims to be the principal journal for social scientists exploring the intersection of race, ethnicity and culture. As book review editor it gives me great pleasure to introduce a new feature of the journal to our readers. From time to time in the State of the Discourse section of the Du Bois Review we will spotlight multiple reviews of a single book. In focusing intently on a single contribution our purpose is to highlight significant pieces of scholarship that provide novel conceptual and/or empirical analysis of ethnoracial dynamics in society. We are especially interested in bringing to the attention of our readers books that provide alternative frameworks and/or set new and daring intellectual agendas for the study of race and ethnicity.
The evo‐devo comet
Authors: Duboule Denis
Published: June 2010

Where is ‘evo‐devo’ going and how will it get there? Denis Duboule analyses the fields of evolution and development and argues that their current marriage is likely a transitory affair.
Activation of the Central Histaminergic System is Involved in Hypoxia-Induced Stroke Tolerance in Adult Mice
Authors: Fan Yan-Ying , Hu Wei-Wei , Dai Hai-Bin , Zhang Jian-Xiang , Zhang Lu-Yi , He Ping , Shen Yao , Ohtsu Hiroshi , Wei Er-Qing , Chen Zhong
Published: June 2010

We hypothesized that activation of the central histaminergic system is required for neuroprotection induced by hypoxic preconditioning. Wild-type (WT) and histidine decarboxylase knockout (HDC-KO) mice were preconditioned by 3 hours of hypoxia (8% O2) and, 48 hours later, subjected to 30 minutes of middle cerebral artery (MCA) occlusion, followed by 24 hours of reperfusion. Hypoxic preconditioning improved neurologic function and decreased infarct volume in WT or HDC-KO mice treated with histamine, but not in HDC-KO or WT mice treated with α-fluoromethylhistidine (α-FMH, an inhibitor of HDC). Laser-Doppler flowmetry analysis showed that hypoxic preconditioning ameliorated cerebral blood flow (CBF) in the periphery of the MCA territory during ischemia in WT mice but not in HDC-KO mice. Histamine decreased in the cortex of WT mice after 2, 3, and 4 hours of hypoxia, and HDC activity increased after 3 hours of hypoxia. Vascular endothelial growth factor (VEGF) mRNA and protein expressions showed a greater increase after hypoxia than those in HDC-KO or α-FMH-treated WT mice. In addition, the VEGF receptor-2 antagonist SU1498 prevented the protective effect of hypoxic preconditioning in infarct volume and reversed increased peripheral CBF in WT mice. Therefore, endogenous histamine is an essential mediator of hypoxic preconditioning. It may function by enhancing hypoxia-induced VEGF expression.
Age-Dependent Effect of Apolipoprotein E4 on Functional Outcome after Controlled Cortical Impact in Mice
Authors: Mannix Rebekah C , Zhang Jimmy , Park Juyeon , Zhang Xuan , Bilal Kiran , Walker Kendall , Tanzi Rudolph E , Tesco Giuseppina , Whalen Michael J
Published: June 2010

The apolipoprotein E4 ( APOE4) gene leads to increased brain amyloid beta (Aβ) and poor outcome in adults with traumatic brain injury (TBI); however, its role in childhood TBI is controversial. We hypothesized that the transgenic expression of human APOE4 worsens the outcome after controlled cortical impact (CCI) in adult but not immature mice. Adult and immature APOE4 mice had worse motor outcome after CCI ( P<0.001 versus wild type (WT)), but the Morris water maze performance was worse only in adult APOE4 mice ( P=0.028 at 2 weeks, P=0.019 at 6 months versus WT), because immature APOE4 mice had performance similar to WT for up to 1 year after injury. Brain lesion size was similar in adult APOE4 mice but was decreased ( P=0.029 versus WT) in injured immature APOE4 mice. Microgliosis was similar in all groups. Soluble brain Aβ40 was increased at 48 hours after CCI in adult and immature APOE4 mice and in adult WT ( P<0.05), and was dynamically regulated during the chronic period by APOE4 in adults but not immature mice. The data suggest age-dependent effects of APOE4 on cognitive outcome after TBI, and that therapies targeting APOE4 may be more effective in adults versus children with TBI.
Three-dimensionally stacked flexible integrated circuit: Amorphous oxide/polymer hybrid complementary inverter using n-type a-In–Ga–Zn–O and p-type poly-(9,9-dioctylfluorene-co-bithiophene) thin-film transistors
Authors: Nomura Kenji , Aoki Takashi , Nakamura Kiyoshi , Kamiya Toshio , Nakanishi Takashi , Hasegawa Takayuki , Kimura Mutsumi , Kawase Takeo , Hirano Masahiro , Hosono Hideo
Published: June 2010

A three-dimensional vertically-stacked flexible integrated circuit is demonstrated based on hybrid complementary inverters made of n-type In–Ga–Zn–O (a-IGZO) amorphous oxide thin-film transistors (TFTs) and p-type poly-(9,9-dioctylfluorene-co-bithiophene) (F8T2) polymer TFTs, where all the fabrication processes were performed at temperatures ≤120 °C. Saturation mobilities of the a-IGZO TFT and the F8T2 TFT are ∼3.2 and ∼1.7×10−3 cm2 V−1 s−1, respectively, from which we chose the appropriate dimensions of the TFTs so as to obtain a good balance for the inverter operation. The maximum voltage gain is ∼67, which is better than those reported for organic/oxide hybrid complementary inverters.
Nature of short-range ferromagnetic ordered state above TC in double perovskite La2NiMnO6
Authors: Zhou S. M. , Guo Y. Q. , Zhao J. Y. , Zhao S. Y. , Shi L.
Published: June 2010

Magnetic measurements of La2NiMnO6 reveal that its inverse susceptibility exhibits an upward derivation from Curie–Weiss behavior above TC, indicating the presence of a short-range ferromagnetic ordered state. It is suggested that the upward derivation is due to antiferromagnetic interactions arising from anitisite defects, which is supported by the magnetic studies on the samples where the antiferromagnetic interactions are modulated by partially doping La with Sr or by decreasing the sample size. Basing on these results, we propose that the short-range ferromagnetic ordering is induced by antisite defects against long-range ferromagnetic ordering of the Ni/Mn sublattice.
Neighbor of Brca1 gene (Nbr1) functions as a negative regulator of postnatal osteoblastic bone formation and p38 MAPK activity
Authors: Whitehouse Caroline A. , Waters Sarah , Marchbank Katie , Horner Alan , McGowan Neil W. A. , Jovanovic Jelena V. , Xavier Guilherme M. , Kashima Takeshi G. , Cobourne Martyn T. , Richards Gareth O. , Sharpe Paul T. , Skerry Tim M. , Grigoriadis Agamemnon E. , Solomon Ellen
Published: June 2010

The neighbor of Brca1 gene (Nbr1) functions as an autophagy receptor involved in targeting ubiquitinated proteins for degradation. It also has a dual role as a scaffold protein to regulate growth-factor receptor and downstream signaling pathways. We show that genetic truncation of murine Nbr1 leads to an age-dependent increase in bone mass and bone mineral density through increased osteoblast differentiation and activity. At 6 mo of age, despite normal body size, homozygous mutant animals (Nbr1
tr/tr
) have ~50% more bone than littermate controls. Truncated Nbr1 (trNbr1) co-localizes with p62, a structurally similar interacting scaffold protein, and the autophagosome marker LC3 in osteoblasts, but unlike the full-length protein, trNbr1 fails to complex with activated p38 MAPK. Nbr1
tr/tr
osteoblasts and osteoclasts show increased activation of p38 MAPK, and significantly, pharmacological inhibition of the p38 MAPK pathway in vitro abrogates the increased osteoblast differentiation of Nbr1
tr/tr
cells. Nbr1 truncation also leads to increased p62 protein expression. We show a role for Nbr1 in bone remodeling, where loss of function leads to perturbation of p62 levels and hyperactivation of p38 MAPK that favors osteoblastogenesis.
Effect of broad- and narrow-spectrum antimicrobials on
Clostridium difficile
and microbial diversity in a model of the distal colon
Authors: Rea Mary C. , Dobson Alleson , O'Sullivan Orla , Crispie Fiona , Fouhy Fiona , Cotter Paul D. , Shanahan Fergus , Kiely Barry , Hill Colin , Ross R. Paul
Published: June 2010

Vancomycin, metronidazole, and the bacteriocin lacticin 3147 are active against a wide range of bacterial species, including
Clostridium difficile
. We demonstrate that, in a human distal colon model, the addition of each of the three antimicrobials resulted in a significant decrease in numbers of
C. difficile
. However, their therapeutic use in the gastrointestinal tract may be compromised by their broad spectrum of activity, which would be expected to significantly impact on other members of the human gut microbiota. We used high-throughput pyrosequencing to compare the effect of each antimicrobial on the composition of the microbiota. All three treatments resulted in a decrease in the proportion of sequences assigned to the phyla
Firmicutes
and
Bacteroidetes
, with a corresponding increase in those assigned to members of the
Proteobacteria
. One possible means of avoiding such “collateral damage” would involve the application of a narrow-spectrum antimicrobial with specific anti-
C. difficile
activity. We tested this hypothesis using thuricin CD, a narrow-spectrum bacteriocin produced by
Bacillus thuringiensis
, which is active against
C. difficile
. The results demonstrated that this bacteriocin was equally effective at killing
C. difficile
in the distal colon model but had no significant impact on the composition of the microbiota. This offers the possibility of developing a targeted approach to eliminating
C. difficile
in the colon, without collateral damage.
Structure of bacterial LigD 3′-phosphoesterase unveils a DNA repair superfamily
Authors: Nair Pravin A. , Smith Paul , Shuman Stewart
Published: June 2010

The DNA ligase D (LigD) 3′-phosphoesterase (PE) module is a conserved component of the bacterial nonhomologous end-joining (NHEJ) apparatus that performs 3′ end-healing reactions at DNA double-strand breaks. Here we report the 1.9 Å crystal structure of
Pseudomonas aeruginosa
PE, which reveals that PE exemplifies a unique class of DNA repair enzyme. PE has a distinctive fold in which an eight stranded β barrel with a hydrophobic interior supports a crescent-shaped hydrophilic active site on its outer surface. Six essential side chains coordinate manganese and a sulfate mimetic of the scissile phosphate. The PE active site and mechanism are unique
vis à vis
other end-healing enzymes. We find PE homologs in archaeal and eukaryal proteomes, signifying that PEs comprise a DNA repair superfamily.
Irregular invariant measures related to Haar measure
Authors: Peterson H. LeRoy
Published: June 2010

Let G be a locally compact nondiscrete group, and let

ν
1

{\nu _1}

be a Haar measure on an open subgroup of

G
G

. It is not hard to show that

ν
1

{\nu _1}

must be the restriction of a Haar measure

ν
\nu

on all of

G
G

. Here we show that there exists a translation invariant measure

μ
\mu

(found by extending

ν
1

{\nu _1}

to the cosets of

H
H

in a natural way) which agrees with

ν
\nu

on, for example,

(
ν
)

(\nu )

σ
\sigma

-finite sets, open sets, and subsets of

H
H

. Although

ν
\nu

can be computed from

μ
\mu

in a relatively simple manner, the two measures are not equal in general. In fact, there is an extreme case, namely when

H
H

is not

σ
\sigma

-compact and has uncountably many cosets, in which

μ
\mu

fails very badly to be regular—there are closed sets on which

μ
\mu

is not inner regular and (other) closed sets on which

μ
\mu

is not outer regular. One condition sufficient for this extreme case to be possible is when

G
G

is Abelian and not

σ
\sigma

-compact.
Jordan’s theorem for solvable groups
Authors: Dornhoff Larry
Published: June 2010

We show that every finite solvable group of

n
×
n

n \times n

matrices over the complex numbers has a normal abelian subgroup of index

≦

2

4
n

/

3
−
1

3

10
n

/

9
−
1

/

3

\leqq {2^{4n/3 - 1}}{3^{10n/9 - 1/3}}

. For infinitely many

n
n

, this bound is best possible.
Periodic solutions for perturbed nonlinear differential equations
Authors: Proctor T. G.
Published: June 2010

The existence of periodic solutions of a periodically perturbed system of nonlinear differential equations is established. The construction of such solutions is proved in a more restricted situation. These results generalize well-known results for perturbed linear differential equations. Examples are given.
A random 𝐿¹ function with divergent Walsh series
Authors: Wells Benjamin B.
Published: June 2010

The purpose of this paper is to point out that the techniques of J. P. Kahane to arrive at almost everywhere divergent Fourier series may be carried over to the Fourier-Walsh system. In particular we construct a random

L
1

{L^1}

function whose Fourier-Walsh series almost surely (a. s.) diverges almost everywhere.
Markov process representations of general stochastic processes
Authors: Johnson Dudley Paul
Published: June 2010

In this paper we show that any separable stochastic process on a compact metric space can be derived from a temporally homogeneous Markov process on the extreme points of a compact convex set of measures.
Metrizability of locally compact vector spaces
Authors: Warner Seth
Published: June 2010

By use of the theory of characters and the Pontryagin-van Kampen theorem, it is shown that if

E
E

is a locally compact vector space over a discrete division ring

K
K

of characteristic zero and if

dim
K

E
>

2

m

{\dim _K}E > {2^\mathfrak {m}}

, where

m

\mathfrak {m}

is the cardinality of

K
K

, then

E
E

is metrizable.
On collections of subsets containing no 4-member Boolean algebra.
Authors: Erdős Paul , Kleitman Daniel
Published: June 2010

In this paper, upper and lower bounds each of the form

c

2
n

/

n

1

/

4

c{2^n}/{n^{1/4}}

are obtained for the maximum possible size of a collection

Q
Q

of subsets of an

n
n

element set satisfying the restriction that no four distinct members

A
,
B
,
C
,
D

A,B,C,D

of

Q
Q

satisfy

A
⋃
B
=
C

A \bigcup B = C

and

A
⋂
B
=
D

A \bigcap B = D

. The lower bound is obtained by a construction while the upper bound is obtained by applying a somewhat weaker condition on

Q
Q

which leads easily to a bound. Probably there is an absolute constant

c
c

so that
\[

max

|

Q

|

=
c

2
n

/

n

1

/

4

+
o
(

2
n

/

n

1

/

4

)

\max |Q| = c{2^n}/{n^{1/4}} + o({2^n}/{n^{1/4}})

\]
but we cannot prove this and have no guess at what the value of

c
c

is.
Homeomorphism groups of weak solenoidal spaces
Authors: Rogers James T. , Tollefson Jeffrey L.
Published: June 2010

It is shown that inverse limit spaces of closed manifolds with covering maps as bonding maps are determined by their homeomorphism groups.
Approximation by homeomorphisms and solution of P. Blass problem on pseudo-isotopy
Authors: Holsztyński W.
Published: June 2010

For every map of

f
:

S
1

→

S
1

=
{
z
∈
C
:

|

z

|

=
1
}

f:{S^1} \to {S^1} = \{ z \in C:|z| = 1\}

of degree 1, existence of apseudo-isotopy

h
:

S
1

×
I
→
R
=
{
z
∈
C
:

|

z

|

≧
1
}

h:{S^1} \times I \to R = \{ z \in C:|z| \geqq 1\}

such that

h
(
z
,
0
)
=
z

h(z,0) = z

and

h
(
z
,
1
)
=
f
(
z
)

h(z,1) = f(z)

is established. On the other hand (i) maps of

I
n

{I^n}

into

I
n

×
0
⊂

E

n
+
1

{I^n} \times 0 \subset {E^{n + 1}}

cannot be, in general, uniformly approximated by homeomorphic embeddings of

I
n

{I^n}

in

E

n
+
1

{E^{n + 1}}

for

n
>
1

n > 1

, and (ii) maps of

S
n

{S^n}

into

S
n

⊂

E
n

{S^n} \subset {E^n}

of degree 1 cannot be, in general, extended to a pseudo-isotopy of

S
n

{S^n}

into

E

n
+
1

{E^{n + 1}}

.
The nonexistence of free 𝑆¹ actions on some homotopy spheres
Authors: Schultz Reinhard
Published: June 2010

In this paper a necessary condition is given for the existence of a free differentiable action of the circle group

S
1

{S^1}

on a

(
4
k
+
1
)

(4k + 1)

-dimensional homotopy sphere. This includes a previously known criterion due to R. Lee and yields additional examples of exotic spheres for which no such actions exist.
Minimal generating sets for free modules
Authors: Bruning L. M. , Leavitt W. G.
Published: June 2010

Let

R
R

be a ring admitting a free module with generating set shorter than the length of a basis. If

n
n

is the shortest basis among all such modules and

m
m

the length of its shortest generating set then

n
=
m
+
1

n = m + 1

and every free module with basis of length

≧
m
+
1

\geqq m + 1

has a generating set of length

m
m

. If

R
R

has module type

(
h
,
k
)

(h,k)

then

m
=
h

m = h

, that is an

R
R

-module with basis of length

u
>
h

u > h

not only has all bases of length

u
u

but also has no generating set of length

>
u

> u

. The integer

m
m

together with the module type define a new ring invariant which satisfies many of the properties of the module type.
Equilateral sets in Minkowski spaces
Authors: Petty C. M.
Published: June 2010

The structure of equilateral sets in an n-dimensional Minkowski space

M
n

{M^n}

is shown to be closely related to the properties of antipodal sets. The range of the cardinality of maximal equilateral sets in

M
n

{M^n}

is obtained and a subset characterization of antipodal sets is derived and applied to equilateral sets.
On congruence indices for simple closed curves
Authors: Wayment S. G.
Published: June 2010

L. M. Blumenthal has defined the concept of congruence indices for point sets in his book Theory and applications of distance geometry, Clarendon Press, Oxford, 1953. Blumenthal shows that the circle has congruence indices (3, 1) and asks if this characterizes the circle among the class of simple closed curves. In this paper it is established that various classes of simple closed curves do not have congruence indices

(
3
,
n
)

(3,n)

for any

n
n

. Included in these classes are the polygons, simple closed curves with convex interiors and a straight line segment contained in the curve, and simple closed curves with continuous nonconstant radius of curvature on some arc. Thus any noncircular simple closed curve with congruence indices (3, 1) must be very pathological. It is shown that if a simple closed curve has positive planar Lebesgue measure, then it fails to have congruence indices

(
3
,
n
)

(3,n)

for any

n
n

.