bluuebunny/crossref_metadata_2025 huggingface dataset:
Don’t Leave Me Hanging on the Anglophone: The Potential for Online Distance Higher Education in the Asia‐Pacific Region
Authors: Marginson Simon
Published: December 2004

In the last decade there have been many attempts to mount online distance higher education programs on a global scale, led by the e‐learning industry and university companies and consortia, some with government support: e.g. Universitas21 Global, Cardean University, Fathom, NYUOnline and the UKe‐University. A primary commercial objective has been student markets in the Asia‐Pacific nations, especially China, given unmet domestic demand and the growth of cross‐border education. However while for‐profit providers such as the University of Phoenix Online have shown mass online programs are viable in targeted markets, albeit more expensive than face‐to‐face programs, would‐be global ventures have faltered or collapsed. The paper reviews the failure of English language global e‐learning in the light of industry marketing strategies, the economics of online education, and the specifics of Asia‐Pacific nations including unmet demand for education. It argues that for exporter universities, the potential of cross‐border online education can only be realised if communications capacity in the Asia‐Pacific nations is enhanced; and online programs are teaching‐intensive, and customised for cultural and linguistic variations. Long‐term equal partnerships with local and system providers are essential. For policy makers, the implosion of global e‐learning points to the need to use expert judgment in relation to the different options for enhancing the capacity of higher education at home and abroad. It also suggests the need for greater scepticism about commercially driven scenarios and claims of company prospectuses, and about the viability of market‐controlled paths of development.
Collaboration with the Community to Widen Participation: ‘Partners’ without Power or Absent ‘Friends’?
Authors: Slack Kim
Published: December 2004

Current discourse around widening participation emphasises the importance of partnership and collaboration. For example, the Learning Skills Council and government policy all cite the need to adopt collaborative approaches to assist with widening participation and student progression. In 1998 the Higher Education Funding Council for England (HEFCE) called for proposals for higher education institutions to build partnerships to widen participation. Successful partnership bids were subsequently funded for a period of one year initially and extended up to three years in total. One of the aims of the partnerships as outlined by the HEFCE was to address uneven rates of demand for higher education amongst certain socio‐economic groups by working in collaboration with other organisations. This article focuses on one aspect of an evaluative research project examining collaboration resulting from the HEFCE initiative: the involvement of communities in developing partnerships. It examines their initial involvement and the extent to which they were then incorporated into ongoing partnerships and decision‐making. Factors that mitigate against community involvement are discussed. It is concluded that although organizational and institutional links can be highly beneficial to realizing the objective of a widened base of involvement in HE there may be a sense in which the role of communities is either neglected, or worse, omitted.
All Together Now? Arts and Social Science Views of Research Assessment in Britain
Authors: Delamont Sara
Published: December 2004

During 2002–2003 there was an enquiry into the future of Research Assessment Exercises in Britain. Learned societies in Arts and Social Sciences who copied their submissions to the author for meta‐analysis held very similar views. However these views are not strongly represented in the published report, because only a small minority of societies submitted evidence.
Consumer acceptance and physicochemical quality of processed red sorrel/roselle (Hibiscus sabdariffa L.) sauces from enzymatic extracted calyces
Authors: D’Heureux‐Calix Faye , Badrie Neela
Published: December 2004

The objectives of this study were to utilize sorrel puree from enzymatic extracted sorrel or roselle (Hibiscus sabdariffa L.) calyces in the processing of sauces and to determine consumer acceptance of sauces with the addition of 0.3% and 0.4% xanthan gum. The physicochemical (particularly colour) and microbial quality changes in sauces were monitored during storage. Pectolase treatment of sorrel calyces resulted in a high yield (94.5%) of puree, but the hue changed (P < 0.05) from red to orange‐yellow. Adjustment of puree to pH 2.3 resulted (P < 0.05) in an intense red colour. Sensory and physicochemical attributes did not differ significantly between sauces except for consistency and hue. Sensory colour was the most liked (P < 0.05) attribute with an instrumental colour ‘L’ 23.5, ‘a’ 3.5 and ‘b’ 0.40. Total soluble solids and pH were 41.0–43.5°Brix and 2.62 ± 0.04, respectively. Sauces were liked slightly to moderately in overall acceptability. A positive correlation (P < 0.05) was noted between the overall acceptability to other sensory attributes. Colour became less dark and red (P < 0.05) on storage at 20°C for 6 weeks. Sauces had < 10 cfu/mL of yeasts and moulds, lactobacilli and total mesophilic aerobes throughout storage at 20°C for 8 weeks. A 25‐g sauce serving provided 0.7‐g dietary fibre or 3% of the daily value. The overall acceptability of sorrel sauce makes it an ideal ingredient for use in the food service industry and inclusion in a number of dishes.
Topical radiant heating in wound healing: an experimental study in a donor site wound model*
Authors: Khan Aadil A , Banwell Paul E , Bakker Martijn C , Gillespie Patrick G , McGrouther Douglas A , Roberts Anthony HN
Published: December 2004

The importance of temperature in the wound‐healing process is rapidly being recognised as a novel way in which to manipulate the wound‐healing environment. In this study, we aimed to investigate the direct effect of topical radiant heating (TRH), using a novel bandaging system (Warm‐Up™, Arizant Healthcare Inc., Eden Prairie MN, USA; Augustine Medical, USA), on wound healing at a physiological and cellular level. Experimental bandages were positioned over split‐thickness skin graft donor site wounds of 12 patients undergoing graft harvesting from the anterior thigh. The experimental group (n = 6) underwent intermittent heating for 5 hours (three 1‐hour heating cycles at 38°C, separated by two 1‐hour rest periods), whilst the control group (n = 6) received no radiant heating. Physiological blood‐flow recordings both in the control group and the topical radiant heat cohort were undertaken using Laser Doppler Imaging (LDI). Skin biopsies were obtained at identical time points, and immunohistochemical analysis was undertaken using antibodies against neutrophils (NP57), lymphocytes (CD3) and macrophages (CD68). We found that TRH significantly increased local dermal blood flow (P < 0·001) by up to 100% in both injured and intact skin. Furthermore, this increase in flow was associated with a significant (P < 0·05) increase in CD3 immunoreactivity on day 1 postoperatively. This study demonstrates that TRH increases local blood flow and lymphocyte (CD3) extravasation, and we postulate that these changes may enhance local innate immunity within the healing wound environment.
COMPLEX DONORS IN NITROGEN-DOPED DIAMOND
Authors: DAI YING , LI ANYI , ZHANG YING , HAN SHENGHAO
Published: December 2004

Several Nitrogen (N)-hydrogen(H), N-dangling bond (DB) and N-single vacancy (V) complexes as the possible donor centers in diamond have been investigated using both supercell and cluster methods within the frame of density functional theory. We have found that the H—N—N—H complex exhibits shallower donor character than that of the N—H—N center discussed by Miyazaki et al.1 and it is one of the possible effective shallow donor centers in crystalline diamond. We conclude that the N—V related complex demonstrates a character of shallow donors and it should be one of the possible donor centers for the ultrananocrystalline diamond (UNCD) films, which are responsible for the n-type high conductivity of these films.
STUDY OF STRUCTURAL AND TRANSPORT PROPERTIES OF IODINATED AMORPHOUS CONDUCTING CARBON FILMS
Authors: KUMARI LATHA , SUBRAMANYAM S. V.
Published: December 2004

Iodine intercalated amorphous conducting carbon (a-C:I) films are prepared by vapor phase pyrolysis of maleic anhydride and iodine. Transmission electron microscopy (TEM), Selected area electron diffraction (SAED) and X-ray photoelectron spectroscopy (XPS) studies reveal the structural changes in the iodinated amorphous conducting carbon (a-C) films. TEM micrographs accounts for a average cluster size of the order of ~900 nm in a-C:I film. SAED study depicts a polycrystalline phase of the intercalated sample. Electrical resistivity of a-C:I samples are found to decrease with the iodine incorporation. Metal–insulator transition is observed as a function of magnetic field.
THE EVOLUTION OF MALE TRAITS IN SOCIAL INSECTS
Authors: Boomsma Jacobus J. , Baer Boris , Heinze Jürgen
Published: December 2004

▪ Abstract  Pair formation in social insects mostly happens early in adult life and away from the social colony context, which precludes promiscuity in the usual sense. Termite males have continuous sperm production, but males of social Hymenoptera have fixed complements of sperm, except for a few species that mate before female dispersal and show male-fighting and lifelong sperm production. We develop an evolutionary framework for testing sexual selection and sperm competition theory across the advanced eusocial insects (ants, wasps, bees, termites) and highlight two areas related to premating sexual selection (sexual dimorphism and male mate number) that have remained understudied and in which considerable progress can be achieved with relatively simple approaches. We also infer that mating plugs may be relatively common, and we review further possibilities for postmating sexual selection, which gradually become less likely in termite evolution, but for which eusocial Hymenoptera provide unusual opportunities because they have clonal ejaculates and store viable sperm for up to several decades.
Peptide blockers of PKG inhibit ROS generation by acetylcholine and bradykinin in cardiomyocytes but fail to block protection in the whole heart
Authors: Krieg Thomas , Philipp Sebastian , Cui Lin , Dostmann Wolfgang R. , Downey James M. , Cohen Michael V.
Published: December 2004

Bradykinin and acetylcholine (ACh) trigger preconditioning by ATP-sensitive K+ (KATP) channel-dependent production of reactive oxygen species (ROS). Recent evidence suggests that ROS production may in turn be influenced by cGMP-dependent protein kinase (PKG). This study utilized DT-2 and DT-3 peptides, highly specific membrane-permeable blockers of PKG. Rabbit cardiomyocytes were incubated for 15 min in reduced MitoTracker red, which becomes fluorescent only after exposure to ROS. Bradykinin (400 nM) and ACh (250 μM) caused a 49.9 ± 5.9% and 46.8 ± 1.7% increase in ROS production, respectively ( P < 0.005 vs. untreated cells). Coincubation with DT-3 (250 nM) abolished both the ACh- and bradykinin-induced ROS signal, whereas a nonpermeable form of the peptide (W45) had no effect on ACh-induced ROS production. DT-3 was unable to block ROS production from diazoxide (100 μM), a selective opener of mitochondrial KATP channels, suggesting that these channels are downstream of PKG. DT-2 (125 nM) also prevented ACh from triggering ROS production. 8-(4-Chlorophenylthio)-guanosine 3′,5′-cyclic monophosphate (100 μM), a cGMP analog and potent direct activator of PKG, increased ROS production of cardiomyocytes by 44.7 ± 7.1% ( P < 0.001 vs. untreated cells). This increase was blocked by DT-2. Neither DT-2 nor DT-3 could block the anti-infarct effect of bradykinin in isolated rabbit hearts. Studies with fluorescent-tagged DT-3 revealed that it was confined to endothelial cells and never reached the myocytes. We conclude that both bradykinin and ACh trigger ROS generation by a pathway that includes PKG. Although the peptides may be inappropriate for a whole heart model, they are likely to become important tool drugs for elucidation of signal transduction pathways in cell preparations.
Leptin-induced satiation mediated by abdominal vagal afferents
Authors: Peters J. H. , McKay B. M. , Simasko S. M. , Ritter R. C.
Published: December 2004

Leptin is a hormone secreted into the systemic blood primarily by white adipose tissue. However, leptin also is synthesized and stored by cells in the gastric mucosa. Because gastric mucosal leptin is secreted in response to ingestion of a meal, we hypothesized that it might contribute to satiation (meal termination) by acting on gastrointestinal vagal afferent neurons. To test whether leptin is capable of acutely reducing short-term food intake, we measured consumption of a liquid meal (15% sucrose) following low-dose leptin administration via the celiac artery, which perfuses the upper gastrointestinal tract. Leptin (1, 3, 10 μg) was infused via a chronically implanted, nonocclusive celiac arterial catheter or via a jugular vein catheter with its tip in the right cardiac atrium. Fifteen percent sucrose intake was then measured for 30 min. We found that leptin dose dependently inhibited sucrose intake when infused through the celiac catheter but not when infused into the general circulation via a jugular catheter. Plasma leptin concentrations in the general circulation following celiac arterial or jugular leptin infusions were not significantly different. Celiac arterial leptin infusion did not reduce meal size in vagotomized or capsaicin-treated rats. Finally, we also found that reduction of meal size by celiac leptin infusion was markedly enhanced when coinfused with cholecystokinin, a gastrointestinal satiety peptide whose action depends on vagal afferent neurons. Our results support the hypothesis that leptin contributes to satiation by a mechanism dependent on gastrointestinal vagal afferent innervation of the upper gastrointestinal tract.
Summability of double sequences by weighted mean methods andTauberian conditions for convergence in Pringsheim′s sense
Authors: Móricz Ferenc , Stadtmüller U.
Published: December 2004

After a brief summary of Tauberian conditions for
ordinary sequences of numbers, we consider summability of double
sequences of real or complex numbers by weighted mean methods
which are not necessarily products of related weighted mean
methods in one variable. Our goal is to obtain Tauberian
conditions under which convergence of a double sequence follows
from its summability, where convergence is understood in
Pringsheim′s sense. In the case of double sequences of real numbers,
we present necessary and sufficient Tauberian conditions, which are so‐called
one‐sided conditions. Corollaries allow these Tauberian conditions
to be replaced by Schmidt‐type slow decrease conditions.
For double sequences of complex numbers, we present necessary and
sufficient so‐called two‐sided Tauberian conditions.
In particular, these conditions are satisfied if the summable
double sequence is slowly oscillating.
Imaging neural crest cell dynamics during formation of dorsal root ganglia and sympathetic ganglia
Authors: Kasemeier-Kulesa Jennifer C. , Kulesa Paul M. , Lefcort Frances
Published: December 2004

The neural crest is a migratory population of cells that produces many diverse structures within the embryo. Trunk neural crest cells give rise to such structures as the dorsal root ganglia (DRG) and sympathetic ganglia (SG),which form in a metameric pattern along the anterior-posterior axis of the embryo. While static analyses have provided invaluable information concerning the development of these structures, time-lapse imaging of neural crest cells navigating through their normal environment could potentially reveal previously unidentified cellular and molecular interactions integral to DRG and SG development. In this study, we follow fluorescently labeled trunk neural crest cells using a novel sagittal explant and time-lapse confocal microscopy. We show that along their dorsoventral migratory route, trunk neural crest cells are highly motile and interact extensively with neighboring cells and the environment, with many cells migrating in chain-like formations. Surprisingly, the segregated pattern of crest cell streams through the rostral somite is not maintained once these cells arrive alongside the dorsal aorta. Instead, neural crest cells disperse along the ventral outer border of the somite, interacting extensively with each other and their environment via dynamic extension and retraction of filopodia. Discrete sympathetic ganglia arise as a consequence of intermixing and selective reorganization of neural crest cells at the target site. The diverse cell migratory behaviors and active reorganization at the target suggest that cell-cell and cell-environment interactions are coordinated with dynamic molecular processes.
Sperm-egg fusion: events at the plasma membrane
Authors: Stein Kathryn K. , Primakoff Paul , Myles Diana
Published: December 2004

Sperm-egg fusion is a cell-cell membrane fusion event essential for the propagation of sexually reproducing organisms. In gamete fusion, as in other fusion events, such as virus-cell and intracellular vesicle fusion, membrane fusion is a two-step process. Attachment of two membranes through cell-surface molecules is followed by the physical merger of the plasma membrane lipids. Recent progress has demonstrated an essential role for an oocyte tetraspanin, CD9, in mouse sperm-egg fusion, and a specific molecular site crucial for CD9 function has been identified. Absence of glycosylphosphatidylinositol-anchored proteins on the oocyte surface also results in loss of oocyte fusion competence in this gamete. These discoveries provide a strong starting point for the identification of additional proteins that have roles in sperm-egg fusion.
The Origins of Complex Language: An Inquiry into the Evolutionary Beginnings of Sentences, Syllables, and Truth
Authors: Lieberman Philip
Published: December 2004

The Origins of Complex Language: An Inquiry into the Evolutionary Beginnings of Sentences, Syllables, and Truth. Andrew Carstairs‐McCarthy. Oxford. Oxford University Press, 1999. 260 pp.
The Construct Validity of Cultures: Cultural Diversity, Culture Theory, and a Method for Ethnography
Authors: Handwerker W. Penn
Published: December 2004

If we distinguish culture (embodied in individuals) from cultures (embodied in the superorganic properties of groups), we make it possible to accommodate the observation that individuals vary, make choices, and exert control over their lives with the observation that those same individuals find themselves constrained by recurrent patterns with properties of things. This shift in perspective makes the central problem for ethnography the identification and description of the evolving configurations of cognition, emotion, and behavior at the intersection of evolving, individually unique cultural sets. Principal components analysis of similarities among informants identifies and describes this intersection and its important variations precisely. Ordinary least squares and logistic multiple regressions test for plausible antecedents of intracultural and intercultural variation, respectively. I illustrate with data on cultural diversity in the relative importance of components that make up a partnership between parents and teachers in the United States and in how to organize these components effectively. I demonstrate the existence of a single model of the importance of these components, with intracultural variation. I demonstrate the existence of two cultural models of how to organize these components into effective parent‐ teacher partnerships (Separate but Equal and Mutual Decision Makers). Discordance between these cultures and the social identities of the cultural participants validates Keesing's claim that culture is not bounded in ways many people have long assumed. The shift in perspective that reconciles Sapir and Kroeber points past culture theory to a theory of culture. As we work out the details, it will also help us make ethnographic sense out of the contemporary world and give us a better grasp of the past one. [Key words: cultural diversity, culture theory, ethnographic methods, ethnology]
"Property" and Aboriginal Land Claims in the Canadian Subarctic: Some Theoretical Considerations
Authors: Nadasdy Paul
Published: December 2004

Many of the world's aboriginal peoples are currently engaged in struggles over land and self‐government with the states that encompass them. In Canada, aboriginal people have effectively used the concept of "aboriginal title" to force the government to negotiate land and self‐government agreements with them. Such agreements, however, along with the notion of "aboriginal title" itself, are based on the European concept of "property"; they grant First Nations "ownership" of certain lands and spell out the rights they possess in relation to those lands. This means that aboriginal people have had to learn to think and speak in the "language of property" as a precondition for even engaging government officials in a dialogue over land and sovereignty. Yet the concept of property is in many ways incompatible with many Canadian First Nation people's views about proper human‐animal/land relations. In this article, I argue that the land claim process—because it forces aboriginal people to think and speak in the language of property—tends to undermine the very beliefs and practices that a land claim agreement is meant to preserve. [Key words: property, First Nations, aboriginal land claims, Canada, Subarctic]
First Recipients of Anthropological Doctorates in the United States, 1891‐1930
Authors: Bernstein Jay H.
Published: December 2004

This article seeks to show the origins of the professionalization of anthropology by examining early doctoral dissertations in this field and their authors. The bibliography consists of citations with biographical details of the authors, when known, of doctoral dissertations in anthropology from United States educational institutions up to 1930. One hundred twenty‐four citations are given all, representing 18 institutions. Forty‐one of the dissertations were not written for degrees in anthropology. Besides documenting existence of anthropological work outside recognized graduate programs of anthropology, the bibliography provides a demographic profile of anthropology and shows the distribution of subdiscipline concentrations and regional foci, as well as patterns in the professional domination of anthropology by graduates of various programs and in the publication of doctoral research. [Keywords: dissertations, anthropology—history, anthropology—bibliography, scholarly communication, graduate education]
Anthropological Knowledge and Native American Cultural Practice in the Liberal Polity
Authors: Boggs James P.
Published: December 2004

U.S. Indian policy is caught between two incommensurable theories or paradigms. First, liberal theory extended the worldviewof early physical science to understand human nature. Providing the conceptual foundation for liberal polities, it largely underwrote U.S. Indian policy into the mid‐20th century. Liberal theory recently has been superceded, as theory, by anthropological culture theory, which better accounts for variations between peoples and the realities of human life. The advent of culture theory marks a major paradigm shift within science and public consciousness. Liberal theory, however, remains the foundation for the powerful ideology of liberalism and the institutional practices of Western capitalism and democracy. Thus arise uncomfortable disjunctions—first, between incommensurable theories that both remain vital forces in public life, and, secondarily, between knowledge and practice. This article explores these contending theoretical formations, disjunctions between them, and illustrates how these disjunctions translate into contemporary argument in U.S. Indian policy.
Primate Ecology and Social Structure Vol. 1: Lorises, Lemurs and Tarsiers: Primate Ecology and Social Structure Vol. 2: New World Monkeys: Primate Ecology and Social Structure Vol. 3: Old World Monkeys and Apes
Authors: Martin R. D.
Published: December 2004

Primate Ecology and Social Structure Vol. 1: Lorises, Lemurs and Tarsiers. Robert W. Sussman. Needham Heights. MA: Pearson Custom Publishing, 1999. 284 pp.

Primate Ecology and Social Structure Vol. 2: New World Monkeys. Robert W. Sussman. Needham Heights. MA: Pearson Custom Publishing, 2000. 207 pp.

Primate Ecology and Social Structure Vol. 3: Old World Monkeys and Apes. Robert W. Sussman. Needham Heights. MA: Pearson Custom Publishing, in press.
Culture Matters: How Values Shape Human Progress
Authors: Jindra Michael
Published: December 2004

Culture Matters: How Values Shape Human Progress. Lawrence E. Harrison and Samuel P. Huntington. eds. New York: Basic, 2000. 348 pp.
At the Edge of the State: Indigenous Peoples and Self‐Determination
Authors: Petersen Glenn
Published: December 2004

At the Edge of the State: Indigenous Peoples and Self‐Determination. Maivân Clech Lâm. Ardsley, NY: Transnational Publishers, Inc., 2000. 232 pp.
Translating Native Latin American Verbal Art: Ethnopoetics and Ethnography of Speaking
Authors: Uzendoski Michael A.
Published: December 2004

Translating Native Latin American Verbal Art: Ethnopoetics and Ethnography of Speaking. Kay Sammons and Joel Sherzer. eds. Washington, DC: Smithsonian Institution Press, 2000. 309 pp.
Separation and Reunion in Modern China
Authors: Moore Robert L.
Published: December 2004

Separation and Reunion in Modern China. Charles Stafford. New York: Cambridge University Press, 2000. 202 pp.
Surveying the Race Concept: A Reply to Lieberman, Kirk, and Littlefield
Authors: Cartmill Matt , Brown Kaye
Published: December 2004

Leonard Lieberman, Rod Kirk, and Alice Littlefield report a significant decrease over the past 20 years in the percentage of physical anthropologists who support the race concept, while Matt Cartmill concludes that use of this concept did not decline during that period among anthropologists who study modern human variation. Neither study contradicts the other, since the two used different definitions and sampled different populations. More extensive sampling of the literature and more reliable survey techniques are needed to resolve the issue, [Keywords: race, history of ideas, biological anthropology]
Hip‐Hop: The Culture, the Sound, the Science; One Planet under a Groove: Hip‐Hop and Contemporary Art
Authors: Codrington Raymond
Published: December 2004

Hip‐Hop: The Culture, the Sound, the Science. The Museum of Science and Industry, Chicago. January 18–May 27, 2002.

One Planet under. Groove: Hip‐Hop and Contemporary Art. The Bronx Museum of the Arts, Bronx, NY. October 26, 2001—March 3, 2002; Walker Art Center, Minneapolis, MN, July 14–October 13, 2002; Spelman College Museum of Fine Art, Atlanta, GA, Spring 2003.
Single-Tooth Replacements in the Esthetic Zone With an Immediate Function Implant: A Preliminary Report
Authors: Locante William M.
Published: December 2004

Patients demand an economic, esthetic, and expedient fashion to replace teeth that are missing in the esthetic zone. The clinical response of a 1-piece spiral immediate-function implant was evaluated for this purpose. The implants were placed into immediate extraction sites as well as healed sites and were provisionalized, and patients were put into immediate function the same day as surgery. Sites that qualified for this technique were based on bone density. Bone density in combination with its aggressive thread design and conservative surgical osteotomy preparation produced a 98.8% success rate over a 3-year period for 86 patients.
Adult education at the margins: A literature review
Authors: Glowacki‐Dudka Michelle , Helvie‐Mason Lora B.
Published: December 2004

This chapter reviews the literature related to the historical, philosophical, and contextual issues that frame why adult education sits at the margins of the academy and society.
Crossing borders of religious difference: Adult learning in the context of interreligious dialogue
Authors: Charaniya Nadira K. , Walsh Jane West
Published: December 2004

Two adult and religious educators—a Muslim and a Jew—demonstrate the impact of interreligious dialogue on personal transformation and democratic social change.
Adult education departments in the entrepreneurial age
Authors: Ilsley Paul J.
Published: December 2004

This chapter explores the marginality of university‐based degree‐granting adult education programs and considers how both hopes and fears add to the discourse about the field's vitality.
Micron‐scale Deformation and Damage Mechanisms of Ti3SiC2 Crystals Induced by Indentation
Authors: Zhang Z.‐F. , Sun Z.‐M. , Zhang H. , Hashimoto H.
Published: December 2004

Vickers hardness, deformation and damage mechanisms of Ti3SiC2 crystals induced by indentation in the load range of 0.25 – 20 N were investigated. The Vickers hardness of Ti3SiC2 crystals decreases with increasing indentation load and finally reaches a constant value of ∼ 4 GPa. The typical deformation and damage modes in Ti3SiC2 crystals include: sliding, buckling, kinking, delamination and cleavage fracture of deformation bands as well as intergranular cracking. A deformation and damage mechanism map for Ti3SiC2 crystals was summarized.
Synthesis and Low Cycle Fatigue Behavior of In‐situ Al‐based Composite Reinforced with Submicron TiB2 and TiC Particulates
Authors: Tjong S.C. , Wang G.
Published: December 2004

Low cycle fatigue behavior of in‐situ aluminum based composite reinforced with submicron TiB2 and TiC particulates was investigated. This novel composite was prepared from the TiO2‐Al‐B‐C system via reactive hot pressing. The incorporation of carbon into such a system induces the formation of TiC particulate at the expense of brittle Al3Ti phase. The influence of submicron particulate formation on the tensile and fatigue properties of the composite is discussed.
Laminated Object Manufacturing (LOM) of SiSiC Composites
Authors: Weisensel L. , Travitzky N. , Sieber H. , Greil P.
Published: December 2004

Carbon templates of laminar structure were manufactured from pyrolysed filter paper sheets by Laminated Object Manufacturing (LOM). The laminates were converted into SiSiC composites by post‐pressureless reactive Si‐infiltration. The microstructure and mechanical properties of the fabricated materials depends on the density, porosity and pore size distribution of the biocarbon preform, which can be varied by changing the parameters of the LOM‐processing.
The Impact of Nanostructuring on the Thermal Conductivity of Thermoelectric CoSb3
Authors: Toprak M. S. , Stiewe C. , Platzek D. , Williams S. , Bertini L. , Müller E. , Gatti C. , Zhang Y. , Rowe M. , Muhammed M.
Published: December 2004

The high concentration of grain boundaries provided by nanostructuring is expected to lower the thermal conductivity of thermoelectric materials, which favors an increase in their thermoelectric figure‐of‐merit, ZT. A novel chemical alloying method has been used for the synthesis of nanoengineered‐skutterudite CoSb3. The CoSb3 powders were annealed for different durations to obtain a set of samples with different particle sizes. The samples were then compacted into pellets by uniaxial pressing under various conditions and used for the thermoelectric characterization. The transport properties were investigated by measuring the Seebeck coefficient and the electrical and thermal conductivities in the temperature range 300 K to 650 K. A substantial reduction in the thermal conductivity of CoSb3 was observed with decreasing grain size in the nanometer region. For an average grain size of 140 nm, the thermal conductivity was reduced by almost an order of magnitude compared to that of a single crystalline or highly annealed polycrystalline material. The highest ZT value obtained was 0.17 at 611 K for a sample with an average grain size of 220 nm. The observed decrease in the thermal conductivity with decreasing grain size is quantified using a model that combines the macroscopic effective medium approaches with the concept of the Kapitza resistance. The compacted samples exhibit Kapitza resistances typical of semiconductors and comparable to those of Si–Ge alloys.
Titelbild: Supramolecular Catalysis of a Unimolecular Transformation: Aza‐Cope Rearrangement within a Self‐Assembled Host (Angew. Chem. 48/2004)
Authors: Fiedler Dorothea , Bergman Robert G. , Raymond Kenneth N.
Published: December 2004

Ein supramolekulares Metall‐Ligand‐System …︁ katalysiert die [3,3]‐sigmatrope Umlagerung von Enammonium‐Gästen in wässriger Lösung. Das Titelbild zeigt einen Vorschlag für den Katalysezyklus. Der räumlich beschränkte Wirthohlraum zwingt das Substrat, in einer reaktiven sesselförmigen Konformation zu binden, und beschleunigt so die Umlagerung. Freisetzen und Hydrolyse des Umlagerungsprodukts ermöglichen eine katalytische Reaktionsführung. Mehr dazu finden Sie in der Zuschrift von R. G. Bergman, K. N. Raymond und D. Fiedler auf S. 6916 ff.
Understanding Noncovalent Interactions: Ligand Binding Energy and Catalytic Efficiency from Ligand‐Induced Reductions in Motion within Receptors and Enzymes
Authors: Williams Dudley H. , Stephens Elaine , O'Brien Dominic P. , Zhou Min
Published: December 2004

Noncovalent interactions are sometimes treated as additive and this enables useful average binding energies for common interactions in aqueous solution to be derived. However, the additive approach is often not applicable, since noncovalent interactions are often either mutually reinforcing (positively cooperative) or mutually weakening (negatively cooperative). Ligand binding energy is derived (positively cooperative binding) when a ligand reduces motion within a receptor. Similarly, transition‐state binding energy is derived in enzyme‐catalyzed reactions when the substrate transition state reduces the motions within an enzyme. Ligands and substrates can in this way improve their affinities for these proteins. The further organization occurs with a benefit in bonding (enthalpy) and a limitation in dynamics (cost in entropy), but does not demand the making of new noncovalent interactions, simply the strengthening of existing ones. Negative cooperativity induces converse effects: less efficient packing, a cost in enthalpy, and a benefit in entropy.
The Transcriptional Coactivator p300 Plays a Critical Role in the Hypertrophic and Protective Pathways Induced by Phenylephrine in Cardiac Cells but Is Specific to the Hypertrophic Effect of Urocortin
Authors: Davidson Sean M. , Townsend Paul A. , Carroll Chris , Yurek‐George Alexander , Balasubramanyam Karanam , Kundu Tapas K. , Stephanou Anastasis , Packham Graham , Ganesan A. , Latchman David S.
Published: December 2004

Anacardic acid is an alkylsalicylic acid obtained from cashew‐nut‐shell liquid, and is a potent inhibitor of p300 histone acetyl‐transferase (HAT) activity. We have used anacardic acid to prevent the induction of hypertrophy in isolated neonatal rat cardiomyocytes. Hypertrophy was detected as an increase in cell size, the rearrangement of sarcomeres into a striated pattern, and the induction of embryonic genes β‐MHC and ANF. p300 inhibition was equally effective at preventing hypertrophy whether it was induced by treatment with the α1‐adrenergic agonist, phenylephrine, or by treatment with urocortin, a member of the corticotrophin‐releasing‐factor family, which stimulates specific G protein‐coupled receptors. Spiruchostatin A is a natural‐product inhibitor of histone deacetylases (HDAC) similar to the depsipeptide FK228 molecule. We have recently synthesized spiruchostatin A and now show that, although HDACs act in opposition to HATs, spiruchostatin A has the same effect as anacardic acid, that is, it prevents the induction of hypertrophy in response to phenylephrine or urocortin. Pretreatment with either phenylephrine or urocortin reduced the extent of death observed after the exposure of isolated cardiomyocytes to simulated ischaemia and reoxygenation. Inhibition of p300 or HDAC activity eliminated the protection conferred by phenylephrine; however, it did not affect the protection conferred by urocortin. Therefore, it might eventually be possible to use chemical inhibitors such as these in a therapeutic setting to dissociate the protective effect and hypertrophic effect of urocortin, enhancing the survival of cardiomyocytes exposed to transient ischemia, while inhibiting the hypertrophic pathway that would otherwise be induced concurrently.
Subsolidus Phase Relation, Crystal Structure and Superconductivity of the SmBa2‐xSrxCu3O7‐δ System.
Authors: Song G. B. , Liang J. K. , Liu F. S. , Yang L. T. , Liu Q. L. , Luo J. , Rao G. H.
Published: December 2004

For Abstract see ChemInform Abstract in Full Text.
Antifluorite‐Type Lithium Chromium Oxide Nitrides: Synthesis, Structure, Order, and Electrochemical Properties.
Authors: Cabana Jordi , Ling Christopher D. , Oro‐Sole Judith , Gautier Damien , Tobias Gerard , Adams Stefan , Canadell Enric , Palacin M. Rosa
Published: December 2004

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[(IMo7O26)2]6‐: A Missing Link Between Molecular and Solid Oxides.
Authors: Honda Daisuke , Ozeki Tomoji , Yagasaki Atsushi
Published: December 2004

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Synthesis of Chiral Monodentate Binaphthophosphepine Ligands and Their Application in Asymmetric Hydrogenations.
Authors: Junge Kathrin , Hagemann Bernhard , Enthaler Stephan , Spannenberg Anke , Michalik Manfred , Oehme Guenther , Monsees Axel , Riermeier Thomas , Beller Matthias
Published: December 2004

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New Application of 1,1,3,3,3‐Pentafluoropropene‐diethylamine Adduct (PFPDEA) as Fluorinating Agent. Synthesis of 3,3,3‐Trifluoropropionates of Vicinal Fluorohydrins.
Authors: Walkowiak J. , Haufe G. , Koroniak H.
Published: December 2004

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Tandem Intramolecular Carbolithiation‐Lithium/Zinc Transmetallation and Applications to Carbon—Carbon Bond‐Forming Reactions.
Authors: Yus Miguel , Oritz Rosa
Published: December 2004

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New 4‐Pentafluorosulfanyl and 4‐Perfluoroalkylthio Derivatives of 1‐Chloro‐2‐nitro‐ and 1‐Chloro‐2,6‐dinitrobenzenes.
Authors: Sipyagin Alexey M. , Enshov Vyacheslav S. , Kashtanov Sergei A. , Bateman Colin P. , Mullen Brian D. , Tan Ying‐Teck , Thrasher Joseph S.
Published: December 2004

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Synthesis of N‐1‐Alkylated 6‐Benzyluracil‐5‐carboxylic Esters as Potential Non‐Nucleoside Reverse Transcriptase Inhibitors.
Authors: Larsen Janus S. , Pedersen Erik B. , Nielsen Claus
Published: December 2004

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One‐Pot Clean Synthesis of 1,8‐Dioxo‐decahydroacridines Catalyzed by p‐Dodecylbenezenesulfonic Acid in Aqueous Media.
Authors: Jin Tong‐Shou , Zhang Jian‐She , Guo Tong‐Tong , Wang Ai‐Qing , Li Tong‐Shuang
Published: December 2004

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Synthesis of Chiral α‐Aminoalkylpyrimidines Using an Enantioselective Three‐Component Reaction.
Authors: Dube Henry , Gommermann Nina , Knochel Paul
Published: December 2004

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Protic Acid (HClO4 Supported on Silica Gel)‐Mediated Synthesis of 2,3‐Unsaturated‐O‐glucosides and a Chiral Furan Diol from 2,3‐Glycals.
Authors: Agarwal Aditi , Rani Shikha , Vankar Yashwant D.
Published: December 2004

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Enantioselective Synthesis of Imperanene via Enzymatic Asymmetrization of an Intermediary 1,3‐Diol.
Authors: Carr Jason A. , Bisht Kirpal S.
Published: December 2004

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Isolation and Characterization of Novel Geldanamycin Analogues.
Authors: Hu Zhihao , Liu Yaoquan , Tian Zong‐Qiang , Ma Wei , Starks Courtney M. , Regentin Rika , Licari Peter , Myles David C. , Hutchinson C. Richard
Published: December 2004

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Total Synthesis and Configurational Assignment of (‐)‐Dictyostatin (I), a Microtubule‐Stabilizing Macrolide of Marine Sponge Origin.
Authors: Paterson Ian , Britton Robert , Delgado Oscar , Meyer Arndt , Poullennec Karine G.
Published: December 2004

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Properties of Ionic Liquid Solvents for Catalysis
Authors: Wilkes John S.
Published: December 2004

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Aluminum Halides
Authors: Saito S.
Published: December 2004

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Regio‐ and Stereoselective Carbon—Carbon Bond Formation in Ionic Liquids
Authors: Calo Vincenzo , Nacci Angelo , Monopoli Antonio
Published: December 2004

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Phosphorus, Arsenic, Antimony and Bismuth
Authors: Francis Matthew D.
Published: December 2004

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B, Al, Ga, In, Tl
Authors: Aldridge Simon
Published: December 2004

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Cyclitols: Conduritols and Related Compounds
Authors: Gueltekin M. Serdar , Celik Murat , Balci Metin
Published: December 2004

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Seasonal change in neuron size and spacing but not neuronal recruitment in a basal ganglia nucleus in the avian song control system
Authors: Thompson Christopher K. , Brenowitz Eliot A.
Published: December 2004

Neural plasticity in the song control system of seasonally breeding songbirds accompanies seasonal changes in singing behavior. The volume of Area X, a song control nucleus that forms a portion of the avian basal ganglia, is 75% larger in the spring than it is in the fall. The neuronal basis of the seasonal plasticity in Area X is largely unknown, however. We examined neuronal attributes of Area X in wild adult male song sparrows (Melospiza melodia) captured during the spring and the fall after being implanted for 30 days with osmotic pumps containing [3H]thymidine. We measured the volume of Area X from thionin‐stained sections, and neuronal density and number, and average area of the soma from sections labeled with an antibody against Hu, a neuron‐specific protein. We sampled two neuron classes: “small” neurons that were most likely striatal‐like spiny neurons and “large” neurons, which most likely included pallidal‐like projection neurons. We also analyzed seasonal patterns of neuronal recruitment to Area X. The average area of the soma and neuronal spacing for both neuronal classes were greater in breeding birds. There was no difference in total neuron number for both neuronal classes between seasons. The average area of the soma and density and number of newly recruited neurons did not vary across seasons. These results demonstrate that seasonal plasticity in Area X includes changes in neuron size and neuronal density, but not changes in the rate at which new neurons are recruited. J. Comp. Neurol. 481:276–283, 2005. © 2004 Wiley‐Liss, Inc.
Optical Saturation in Fluorescence Correlation Spectroscopy under Continuous‐Wave and Pulsed Excitation
Authors: Gregor Ingo , Patra Digambara , Enderlein Jörg
Published: December 2004

A detailed theoretical and experimental study of the dependence of fluorescence correlation measurements on optical excitation power due to optical saturation effects is presented. It is shown that the sensitivity of a fluorescence correlation measurement on excitation power becomes increasingly stronger for decreasing excitation power. This makes exact measurements of diffusion coefficients with fluorescence correlation spectroscopy rather difficult. A strong difference of this behavior for continuous‐wave and pulsed excitation is found.
Theoretical Analysis of Pyridine Protonation in Water Clusters of Increasing Size
Authors: Sicilia M. Carmen , Muñoz‐Caro Camelia , Niño Alfonso
Published: December 2004

The protonation of pyridine in water clusters as a function of the number of water molecules was theoretically analyzed as a prototypical case for the protonation of organic bases. We determined the variation of structural, bonding, and energetic properties on protonation, as well as the stabilization of the ionic species formed. Thus, we used supermolecular models in which pyridine interacts with clusters of up to five water molecules. For each complex, we determined the most stable unprotonated and protonated structures from a simulated annealing at the semi ab initio level. The structures were optimized at the B3LYP/cc‐pVDZ level. We found that the hydroxyl group formed on protonation of pyridine abstracts a proton from the ortho‐carbon atom of the pyridine ring. The “atoms in molecules” theory showed that this CH group loses its covalent character. However, starting with clusters of four water molecules, the CH bond recovers its covalent nature. This effect is associated with the presence of more than one ring between the water molecules and pyridine. These rings stabilize, by delocalization, the negative charge on the hydroxyl oxygen atom. Considering the protonation energy, we find that the protonated forms are increasingly stabilized with increasing size of the water cluster. When zero‐point energy is included, the variation follows closely an exponential decrease with increasing number of water molecules. Analysis of the vibrational modes for the strongest bands in the IR spectra of the complexes suggests that the protonation of pyridine occurs by concerted proton transfers among the different water rings in the structure. Symmetric water stretching was found to be responsible for hydrogen transfer from the water molecule to the pyridine nitrogen atom.
NOD mice have a severly impaired ability to recruit leukocytes into sites of inflammation
Authors: Bouma Gerben , Nikolic Tatjana , Coppens Jojanneke M. C. , van Helden‐Meeuwsen Cornelia G. , Leenen Pieter J. M. , Drexhage Hemmo A. , Sozzani Silvano , Versnel Marjan A.
Published: December 2004

The accumulation of macrophages (MΦ) and dendritic cells (DC) in the pancreas plays a crucial role in the pathogenesis of autoimmune diabetes. We studied the recruitment of monocytes, MΦ and DC to sites of inflammation, i.e. the peritoneal cavity and a subcutaneously elicited air pouch in the NOD mouse model of autoimmune diabetes. The leukocyte recruitment was studied from 1 to 7 days after injection of thioglycollate (peritoneum), C5a (peritoneum, air pouch), CCL2 and CCL3 (air pouch). C57BL/6 and BALB/c mice served as controls. Morphological and flow cytometric analysis of the recruited cells was performed, IL‐1β, TNF‐α, IL‐6, IL‐12 and IL‐10 in exudates measured, and in vitro CCL2‐chemotaxis of exudate MΦ (Boyden chamber) determined. NOD mice were strongly impaired in the recruitment of MΦ, DC, monocytes, and granulocytes. Chemokine‐injected air pouches of NOD mice showed an increased IL‐10 and a decreased IL‐1β level, while the other cytokines were normally or very lowly expressed. In addition, NOD exudate MΦ displayed an impaired in vitro CCL2‐induced migration. Our data show that NOD mice have an impaired ability to recruit leukocytes into sites of inflammation elicited in the peritoneum and the air pouch. A raised IL‐10/IL‐1β ratio at these sites and a deficient migratory capacity of NOD monocytes are important determinants in this impairment.