bluuebunny/crossref_metadata_2025 huggingface dataset:
The Multimedia Dictionary of American Sign Language: Learning Lessons about Language, Technology, and Business
Authors: Wilcox Sherman
Published: February 2007

The Multimedia Dictionary of American Sign Language (MM- DASL) was conceived in the late 1980s as a melding of the pioneering work in American Sign Language (ASL) lexicography that William C. Stokoe and his colleagues had carried out decades earlier and the newly emerging computer technologies that were integrating the use of graphical user-interface designs, rapidly searchable databases, and the display of video data. The integration of signed language lexicography and computer technology seemed to be an opportunity to make their work more widely accessible. This article reports on that undertaking.
The Eastern Andean Frontier (Bolivia and Argentina) and Latin American Frontiers: Comparative Contexts (19th and 20th Centuries)
Authors: Langer Erick D.
Published: February 2007

The epic struggles between Mexicans and the Apaches and Comanches in the far northern reaches of the Spanish empire and the conflict between gauchos and Araucanians in the pampas in the far south are the images the mind conjures up when thinking of Latin American frontiers. We must now add for the twentieth century the dense Amazon jungle as one of the last frontiers in popular (and scholarly) minds. However, these images ignore the eastern Andean and Chaco frontier area, one of the most vital and important frontier regions in Latin America since colonial times, today divided up into three different countries (Argentina, Bolivia, Paraguay) in the heart of the South American continent. This frontier region has not received sufficient attention from scholars despite its importance in at least three different aspects: First, the indigenous peoples were able to remain independent of the Creole states much longer than elsewhere other than the Amazon. Secondly, indigenous labor proved to be vitally important to the economic development along the fringes, and thirdly, a disastrous war was fought over the region in the 1930s by Bolivia and Paraguay. This essay provides an overview based on primary and secondary sources of the history of the eastern Andean frontier and compares it to other frontiers in Latin America. It thus endeavors to contribute to frontier studies by creating categories of analysis that make possible the comparisons between different frontiers in Latin America and placing within the scholarly discussion the eastern Andean region during the nineteenth and early twentieth centuries.
Sennacherib, Archimedes, and the Water Screw: The Context of Invention in the Ancient World
Authors: Dalley Stephanie , Oleson John Peter
Published: February 2007

Invention of the water screw is traditionally credited to the third-century B.C. Greek scientist-engineer Archimedes, on the basis of numerous Greek and Latin texts and the technological context of Hellenistic Alexandria. An Assyrian text from the seventh century B.C. may be interpreted to show that king Sennacherib cast such a device in bronze at Nineveh, for use in his palace garden. Such an argument may be strengthened by comparison with details of Assyrian technical capabilities in large-scale casting and in making bearings, and with later Greek texts referring to the Hanging Gardens of Babylon. The method for casting a bronze screw implied in the Assyrian text and instructions for building a wooden water screw provided by Vitruvius were reproduced for a television program. Arguments are presented for and against the invention of the device centuries before Archimedes, together with a discussion of the social context in which such inventions took place in antiquity.
Plantation Factories: Science and Technology in Late-Eighteenth-Century Cuba
Authors: Portuondo Maria M
Published: February 2007

This article studies efforts by a group of plantation owners in Havana to increase production at their sugar plantations by introducing chemical sciences and new foreign technologies to their mills. The modernization plans were debated versus the conventional alternative: increasing capacity by importing hundreds of thousands of slaves and scaling up traditional methods of processing sugar. Plantation owners sought to also clarify the distinction between science and technology and better understand how each promised to advance sugar production. This clarification resulted in a conceptual division between science and technology that shaped the Cuban sugar industry. It also contributed to re-define what it meant to be an "expert" sugar master to the exclusion of the artisans that had for centuries worked as such. The tensions explored in this article illustrate many of the difficulties of transferring immature sciences and new technologies to a non-originating country.
Women and Oaths in Euripides
Authors: Fletcher Judith
Published: February 2007

The plots of three Euripidean tragedies, the Medea, the Hippolytus, and the Iphigenia at Aulis, are driven by oaths sworn by men to women. Women gain control not only of men's language and action, a distortion of the normative social hegemony, but also of the script itself. In all three plays women's power is substantiated by additional oaths of solidarity sworn by female choruses. The catastrophes of the Medea and the Hippolytus are direct consequences of women's control of language, while the twinned oaths of Pylades and Iphigenia dilute this control and contribute to the salutary outcome of the Iphigenia.
Performing Culture(s): Extras and Extra-Texts in Sabina Berman's eXtras
Authors: Bixler Jacqueline Eyring
Published: February 2007

For almost thirty years, Mexican dramatist Sabina Berman has been writing and producing plays that question and often ridicule notions of gender, political credibility, historical authority, and cultural identity. Her latest play, eXtras (2003), is not a Berman original, but rather a translation and adaptation of Marie Jones's highly acclaimed Stones in His Pockets. The bold, capital "X" and multiple connotations of the title are but the external wrapping of a complicated text / translation / performance that extends from Ireland to Mexico, from actor to audience, and finally from Hollywood to the rest of global culture. Theories of performance and cultural resistance shed light on the complexity and playfulness with which Berman translates, adapts, stages, and ultimately subverts Hollywood's hold on cultural representation and, by extension, the hold of US culture on those parts of the world where dire economic conditions and free-trade capitalism force local culture to sell out to global (i.e., first world) culture. In this intercultural performance of texts and extra-texts, Berman and her own hired "extras" underscore what it means to be an extra in the full sense of the word and in today's global(ized) society.
Equity in the Age of Informality: Labour Markets and Redistributive Politics in South Africa
Authors: Friedman Steven
Published: February 2007

Steven Friedman argues that changes in the production process and the consequent increase in informal economic activity has profound implications for redistributive politics in South Africa.
The South African Nation
Authors: Chipkin Ivor
Published: February 2007

Ivor Chipkin considers South African nation-building and
democracy through a look at ANC and BC conceptualisations of
'freedom' and 'the people'.
Land Rights and Democratisation: Rural Tenure Reform in South Africa's Former Bantustans
Authors: Ntsebeza Lungisile
Published: February 2007

Lungisile Ntsebeza questions the governmentÕs intentions with regard to the official future of chiefs. Prospects of democratic local government clash with increasing willingness to compromise with local chiefly power.
Writing Intensive Courses in Theatre
Authors: Roost Alisa
Published: February 2007

Inspired by the Writing Across the Curriculum/Writing in the Disciplines approaches, this article explores the learning styles of theatre majors, approaches to structuring writing intensive courses and structuring and staging high stakes assignments. It includes strategies for honoring creativity, emotions and intuitions as part of the intellectual process and techniques for mentoring and grading in a time efficient way.
A Recipe for American Jewish Integration: The Adventures of Ktonton and Hillels Happy Holidays
Authors: Krasner Jonathan B
Published: February 2007

Two of the most popular
Jewish children's books of the 1930s, Sadie Rose Weilerstein's The Adventures of K'tonton (Women's
League of the United Synagogue, 1935)
and Mamie Goldsmith Gamoran's Hillel's Happy Holidays (Union of American Hebrew
Congregations, 1939), provide a window into the Jewish educational agenda of the interwar years.
Both exemplify the balancing act that American Jews sought to perform between
the prevailing assimilationist ethos and their allegiance to
Jewish continuity. The publication of these two volumes signaled that American
Jewish educators had embraced Horace Kallen's formulation of
cultural pluralism, in effect rejecting both the radical paths of wholesale assimilation and ethnic isolationism.
Economic Reform and Political Transition in Africa The Quest for a Politics of Development
Authors: Lewis Peter M.
Published: February 2007

The 1980s were bracketed by crises in Africa, as protracted economic malaise was succeeded by a wave of political reform. Analysts have sought to understand the sources of economic decline as well as the political requisites for recovery in the region. Neoclassical and structuralist analyses have been challenged by state-centric views of economic change. The latter perspective emphasizes the need for capable developmental states as a basis for long-term adjustment, but a political theory of economic change is still lacking. Such a theory must address the institutional foundations of growth, as well as the shifting basis of social coalitions in African regimes. Political liberalization suggests the possibility of a new setting for economic reform, though the effects of political reform on institutions and coalitions remain ambiguous, and democratization cannot be regarded as a panacea for the region's developmental failure. Future research must look more closely at the interests and structures in transitional regimes, and scholars should adopt a more comparative vantage on Africa's challenges of reform.
Game Theory and the Spiral Model
Authors: Kydd Andrew
Published: February 2007

When one state engages in a military buildup, other states sometimes take this as a sign that it is more aggressive or expansionist than they previously thought. Some argue that such increases in mutual suspicion can drive arms races and even lead to war. Psychological bias is often invoked to explain this pattern of growing suspicions leading to hostility. This article presents an incomplete information model of an arms race and investigates when escalations should rationally generate increased fears and when, in order to reduce such fears, security seekers can refrain from building. It shows that escalations rationally provoke fear even in the absence of bias and that weak states and states facing high costs of arms racing and war will be especially likely to refrain from building as a way of signaling benign intentions.
“New” and “Old” Civil Wars: A Valid Distinction?
Authors: Kalyvas Stathis N.
Published: February 2007

This article questions the prevalent argument that civil wars have fundamentally changed since the end of the cold war. According to this argument, “new” civil wars are different from “old” civil wars along at least three related dimensions—they are caused and motivated by private predation rather than collective grievances and ideological concerns; the parties to these conflicts lack popular support and must rely on coercion; and gratuitous, barbaric violence is dispensed against civilian populations. Recent civil wars, therefore, are distinguished as criminal rather than political phenomena. This article traces the origins of this distinction and argues that it is based on an uncritical adoption of categories and labels, combined with deficient information on “new” civil wars and neglect of recent historical research on “old” civil wars. Perceived differences between post—cold war conflicts and previous civil wars may be attributable more to the demise of readily available conceptual categories caused by the end of the cold war than to the end of the cold war per se.
The Perils of Polarization: Economic Performance in the Postcommunist World
Authors: Frye Timothy
Published: February 2007

Perhaps the most striking feature of the postcommunist transformation is the tremendous variation in rates of economic growth across countries. To account for these differences, this article develops an alternative to the J-curve and partial reform views that currently dominate discussions of the politics of economic reform. This approach treats economic performance as a political struggle between excommunist and anticommunist factions engaged in a war of attrition over economic and political resources. Using a pooled time-series analysis of economic growth across twenty-five postcommunist countries for the period 1990–98, it finds that political polarization between ex-communist and anticommunist factions has had a devastating effect on economic growth. Where these competing factions have had roughly equal power and have struggled over the economic rules of the game—as in Bulgaria or Ukraine—economic growth has been slow. In contrast, where either excommunist or anticommunist factions have dominated the political scene—as in Estonia or Uzbekistan—economic performance has been much better. In addition, economic growth has followed the electoral calendar in polarized countries. As elections approach and the odds of a change in economic policy increase, growth rates have plummeted in polarized countries. These findings have implications for studies of the postcommunist transformation, the political business cycle, and the politics of economic reform more generally.
Beyond the Fiction of Federalism: Macroeconomic Management in Multitiered Systems
Authors: Rodden Jonathan , Wibbels Erik
Published: February 2007

Recent research on federalism is extremely divided. While some tout the benefits of “market-preserving” federalism, others point to the fragmentation and incoherence of policy in federal states. This research bridges the divide by analyzing the political andfiscalstructures that are likely to account for the highly divergent economic experiences of federal systems around die world. To test these propositions, the authors use an original data set to conduct analyses of budget balance and inflation infifteenfederationsaround the world from 1978 through 1996. The empirical research suggests that the level of fiscal decentralization, the nature of intergovernmental finance, and vertical partisan relations all influence macroeconomic outcomes. The find- ings have broad implications for the widespread move toward greater decentralization and for the theoretical literatures on federalism and macroeconomics.
Deciphering Disorder in Africa: Is Identity the Key?
Authors: Young Crawford
Published: February 2007

At the beginning of the 1990s, a wave of democratization raised new hopes for peace in Africa, but as the decade progressed, violent politics spread and formed two large arcs of conflict that weakened or even collapsed states could not contain. This review article examines five recent books that address the potential impact of identity politics on civil violence in Africa. Two of the authors—Donald Horowitz and Ted Gurr—address these issues in a global comparison, while the other three—Luis Martinez, Stephen Ellis, and Mahmood Mamdani—examine important African instances of protracted internal warfare, in Algeria, Liberia, and Rwanda, respectively. Is identity politics the primary instigator of disorder? What is die impact of a prolonged period of state crisis upon communal relationships? The volumes under review offer useful insights, but large questions remain.
Representation and Event: Anselm Kiefer, Joseph Beuys, and the Memory of the Holocaust
Authors: Biro Matthew
Published: February 2007

This essay explores the relationship between representation and event in the work of German artists Anselm Kiefer and Joseph Beuys. It focuses on the ways in which Kiefer and Beuys engage with an evolving constellation of problems, discourses, and representational strategies that developed in West German culture and abroad in response to the events of genocide. The paradoxes of Holocaust representation, it is argued, reveal themselves in the conflict between the moral imperative to remember and the impossibility of representing a past that by its singularity, incomprehensibility, and horror evades clear representation.
Eliot's Recessional: Four Quartets, National Allegory, and the End of Empire
Authors: Esty Joshua
Published: February 2007

This essay presents T. S. Eliot not as a conservative dinosaur, but as an active and imaginative participant in England's transition from imperial center to welfare state and in the conceptual revolution whereby an anthropological concept of national culture displaced a modernist concept of international art. Reading Eliot's late prose and poetry in the context of British decline, it argues that Four Quartets, in all its formal complexity, manages to absorb the residual signs of European universalism into an emergent language of cultural particularism. This interpretation moves beyond the stalled debate between "local" and "universal" readings of the poem by describing the reciprocal constitution of the local and the universal at a specific transitional moment in the history of both modernism and imperialism.
Translation's Challenge to Critical Categories: Verses from French in the Early English Renaissance
Authors: Coldiron A. E. B. (Anne E. B.)
Published: February 2007

From their birth, translations challenge major critical categories: language, nation, authorship, period. This essay describes and theorizes a large, unstudied corpus of category-challenging translations. Most poetry coming from the first English presses (1476-1557) was translated; of the vernaculars, most by far was translated from French. As translations do, the 100,000+ printed lines taken from French both foreground and suppress the foreign. They disrupt accepted accounts of English Petrarchism and literary nation-formation, revealing a
post-colonial French-English biculturalism lingering centuries after 1066. These translations challenge fixed critical narratives about Renaissance poetry and linear "source-influence" methods, inviting a comparative historicist methodology.
Translating Derrida on Translation: Relevance and Disciplinary Resistance
Authors: Venuti Lawrence
Published: February 2007

This essay is an exploration of the theoretical and practical problems posed by translating Jacques Derrida's essay "What is a 'relevant' translation?" into English, given the peculiar marginality of translation in academic institutions, especially in the United States. Whereas cultural studies exhibits a theoreticism that strips translation of its material specificity, translation studies exhibits an empiricism that suppresses the philosophical and political implications of translation. These limitations motivated translation strategies that aim not only to address the two constituencies in terms that are intelligible to each, but to alter the very terms in which we understand and study translation.
The Neural Code of Auditory Phantom Perception
Authors: Weisz Nathan , Müller Simona , Schlee Winfried , Dohrmann Katalin , Hartmann Thomas , Elbert Thomas
Published: February 2007

Tinnitus is defined by an auditory perception in the absence of an external source of sound. This condition provides the distinctive possibility of extracting neural coding of perceptual representation. Previously, we had established that tinnitus is characterized by enhanced magnetic slow-wave activity (∼4 Hz) in perisylvian or putatively auditory regions. Because of works linking high-frequency oscillations to conscious sensory perception and positive symptoms in a variety of disorders, we examined gamma band activity during brief periods of marked enhancement of slow-wave activity. These periods were extracted from 5 min of resting spontaneous magnetoencephalography activity in 26 tinnitus and 21 control subjects. Results revealed the following, particularly within a frequency range of 50–60 Hz: (1) Both groups showed significant increases in gamma band activity after onset of slow waves. (2) Gamma is more prominent in tinnitus subjects than in controls. (3) Activity at ∼55 Hz determines the laterality of the tinnitus perception.

Based on present and previous results, we have concluded that cochlear damage, or similar types of deafferentation from peripheral input, triggers reorganization in the central auditory system. This produces permanent alterations in the ongoing oscillatory dynamics at the higher layers of the auditory hierarchical stream. The change results in enhanced slow-wave activity reflecting altered corticothalamic and corticolimbic interplay. Such enhancement facilitates and sustains gamma activity as a neural code of phantom perception, in this case auditory.
XenopusVocalizations Are Controlled by a Sexually Differentiated Hindbrain Central Pattern Generator
Authors: Rhodes Heather J. , Yu Heather J. , Yamaguchi Ayako
Published: February 2007

Male and female African clawed frogs (Xenopus laevis) produce rhythmic, sexually distinct vocalizations as part of courtship and mating. We found thatXenopusvocal behavior is governed by a sexually dimorphic central pattern generator (CPG) and that fictive vocalizations can be elicited from anin vitrobrain preparation by application of serotonin or by electrical stimulation of a premotor nucleus. Male brains produced fictive vocal patterns representing two calls commonly produced by malesin vivo(advertisement and amplectant call), as well as one call pattern (release call) that is common for juvenile males and femalesin vivobut rare for adult males. Female brains also produced fictive release call. The production of male calls is androgen dependent inXenopus; to test the effects of androgens on the CPG, we examined fictive calling in the brains of testosterone-treated females. Both fictive male advertisement call and release call were produced. This suggests that allXenopuspossess a sexually undifferentiated pattern generator for release call. Androgen exposure leads to a gain-of-function, allowing the production of male-specific call types without prohibiting the production of the undifferentiated call pattern. We also demonstrate that the CPG is located in the brainstem and seems to rely on the same nuclei in both males and females. Finally, we identified endogenous serotonergic inputs to both the premotor and motor nuclei in the brainstem that may regulate vocal activityin vivo.
Hypo-Osmolar Stress Induces p75NTR Expression by Activating Sp1-Dependent Transcription
Authors: Ramos Alberto , Chi Ho Wai , Forte Stephanie , Dickson Kathleen , Boutilier Jacqueline , Favell Kristy , Barker Philip A.
Published: February 2007

Injury-induced expression of the p75 neurotrophin receptor (p75NTR) in the CNS facilitates neuronal apoptosis and prevents neuronal regrowth, but the mechanisms regulating p75NTR expression are poorly characterized. In this study, we showed that hypo-osmolarity induces p75NTR expression in primary neurons, and, using a comparative genomics approach, we identified conserved elements in the 25 kb upstream sequences of the rat, mouse, and human p75NTR genes. We found that only one of these, a proximal region rich in Sp1 sites, responds to changes in hypo-osmolarity. We then showed that Sp1 DNA binding activity is increased in cells exposed to hypo-osmolarity, established that hypo-osmolarity enhanced Sp1 binding to the endogenous p75NTR promoter, and showed that Sp1 is required for p75NTR expression induced by hypo-osmolarity. We examined how Sp1 is regulated to effect these changes and established that Sp1 turnover is strongly inhibited by hypo-osmolarity. We propose that stress-induced Sp1 accumulation that results from reductions in Sp1 turnover rate contributes to injury-induced gene expression.
The Inhalation Anesthetic Isoflurane Induces a Vicious Cycle of Apoptosis and Amyloid β-Protein Accumulation
Authors: Xie Zhongcong , Dong Yuanlin , Maeda Uta , Moir Robert D. , Xia Weiming , Culley Deborah J. , Crosby Gregory , Tanzi Rudolph E.
Published: February 2007

The anesthetic isoflurane has been reported to induce apoptosis and increase Aβ generation and aggregation. However, the molecular mechanism underlying these effects remains unknown. We therefore set out to assess whether the effects of isoflurane on apoptosis are linked to amyloid β-protein (Aβ) generation and aggregation. For this purpose, we assessed the effects of isoflurane on β-site amyloid β precursor protein (APP)-cleaving enzyme (BACE) and γ-secretase, the proteases responsible for Aβ generation. We also tested the effects of inhibitors of Aβ aggregation (iAβ5, a β-sheet breaker peptide; clioquinol, a copper–zinc chelator) on the ability of isoflurane to induce apoptosis. All of these studies were performed on naive human H4 neuroglioma cells as well as those overexpressing APP (H4-APP cells). Isoflurane increased the levels of BACE and γ-secretase and secreted Aβ in the H4-APP cells. Isoflurane-induced Aβ generation could be blocked by the broad-based caspase inhibitor Z-VAD. The Aβ aggregation inhibitors, iAβ5 and clioquinol, selectively attenuated caspase-3 activation induced by isoflurane. However, isoflurane was able to induce caspase-3 activation in the absence of any detectable alterations of Aβ generation in naive H4 cells. Finally, Aβ potentiated the isoflurane-induced caspase-3 activation in naive H4 cells. Collectively, these findings suggest that isoflurane can induce apoptosis, which, in turn, increases BACE and γ-secretase levels and Aβ secretion. Isoflurane also promotes Aβ aggregation. Accumulation of aggregated Aβ in the media can then promote apoptosis. The result is a vicious cycle of isoflurane-induced apoptosis, Aβ generation and aggregation, and additional rounds of apoptosis, leading to cell death.
Rosiglitazone treatment increases plasma levels of adiponectin and decreases levels of resistin in overweight women with PCOS: a randomized placebo-controlled study
Authors: Majuri A , Santaniemi M , Rautio K , Kunnari A , Vartiainen J , Ruokonen A , Kesäniemi Y A , Tapanainen J S , Ukkola O , Morin-Papunen L
Published: February 2007

Objective: Abdominal obesity, insulin resistance and compensatory hyperinsulinaemia play a central role in the pathogenesis of the polycystic ovary syndrome (PCOS). Abdominal adipose tissue is a source of adipokines, such as adiponectin and resistin, both of which may be involved in the development of insulin resistance and chronic inflammation in PCOS. Ghrelin, an important regulatory peptide of food intake, may also play a role in metabolic disturbances related to PCOS.

The aim of this study was to examine the effects of 4 months of treatment with the insulin sensitizer rosiglitazone on plasma adiponectin, resistin and ghrelin levels in overweight women with PCOS. Design: A randomised placebo-controlled study.

Methods: Thirty overweight/obese women with PCOS (body mass index>25 kg/m2, mean age 29.1± 1.2 (s.e.m.) years) were randomly allocated to either rosiglitazone (Avandia, 4 mg twice a day) or placebo treatment. Plasma levels of adiponectin, resistin and ghrelin and their correlation to serum levels of insulin, C-peptide and steroid hormones, and insulin sensitivity (euglycaemic hyperinsulinaemic clamp) were assessed.

Results: Adiponectin and ghrelin levels correlated significantly with most metabolic markers of insulin resistance and with serum levels of DHEA and 17-hydroxyprogesterone. Plasma levels of adiponectin increased from 9.26±0.90 (s.e.m.) to 22.22±3.66 μg/ml (P<0.001) and those of resistin decreased from 12.57±1.63 to 9.21±0.53 ng/ml (P=0.009) at 4 months of treatment, but plasma ghrelin levels did not change.

Conclusions: Rosiglitazone had beneficial effects on serum levels of adiponectin and resistin, suggesting that these adipocytokines may contribute to the improvement in insulin sensitivity observed during the treatment.
Effect of 2 years of high-dose growth hormone therapy on cognitive and psychosocial development in short children born small for gestational age
Authors: Lagrou K , Vanderfaeillie J , Froidecoeur C , Thomas M , Massa G , Tenoutasse S , Craen M , Lebrethon M C , Beckers D , Francois I , Rooman R , Thiry-Counson G , de Beaufort C , De Schepper J
Published: February 2007

Objective and design: Children born small for gestational age (SGA) are not only at risk for short stature, but also for neurodevelopmental and behavioral problems. In this study, we analyzed the effects of high-dose GH therapy on cognitive development and psychosocial functioning in 34 prepubertal (3–8 years) short SGA children, equally randomized into a GH-treated group (TRG) and an untreated group (UTRG).

Methods: At start and after 2 years, children underwent standardized tests measuring the intellectual abilities (Wechsler Preschool and Primary Scale of Intelligence-Revised, or Wechsler Intelligence Scale for Children-Revised); their parents completed a standardized questionnaire evaluating psychosocial functioning (Child Behavior Checklist; CBCL).

Results: At start, total IQ scores were significantly (P < 0.05) lower in the SGA group than in the general population: 32% of the SGA patients had scores below 85. After 2 years, IQ scores remained unchanged in the TRG, but increased significantly (P < 0.05) in the UTRG. After exclusion of children with developmental problems, however, no significant changes in IQ scores occurred in the UTRG as well as the TRG. At baseline, 24% (8/34) children had problematic CBCL total problems scores, equally distributed among the two groups; no significant changes in the different subscale scores occurred after 2 years.

Conclusion: No beneficial effect of 2 years of GH therapy on cognitive and behavioral profile could be observed in a cohort of rather young short SGA children presenting a variable degree of developmental delay and behavioral problems. Subsequent follow-up could reveal potential long-term effects of GH therapy on development and behavior.
Surgical denervation of porcine ovaries during the middle luteal phase of the oestrous cycle changes their morphology and steroidogenic activity
Authors: Jana Barbara , Dzienis Anna , Wojtkiewicz Joanna , Kaczmarek Monika , Majewski M.
Published: February 2007

Changes in both the morphology and the steroidogenic activity of porcine ovaries denervated surgically on day 12 of the oestrous cycle were studied. Neurectomy of the plexus and the superior ovarian nerves caused a dramatic reduction in the number (or even a disappearance) of dopamine-β-hydroxylase- and/or neuropeptide tyrosine-immunoreactive nerve terminals. On day 20 of the subsequent oestrous cycle, the number of small follicles increased (P < 0.01) and that of large follicles decreased (P < 0.05) in the denervated ovaries, as compared to the controls. Neurectomy led to a decrease in the level of progesterone (P
4
; P < 0.001) and androstenedione (A
4
; P < 0.01) in the fluid from small follicles, A
4
(P < 0.001) and testosterone (T; P < 0.05) in the fluid from medium-sized follicles, as well as in the content of all these steroids in the fluid from large-sized follicles (P < 0.001 for P
4
and P < 0.05 for A
4
and T). Denervation also caused a decrease in the content of A
4
(P < 0.01) and T (P < 0.001) in the wall of follicles. Neurectomy resulted in a significant increase in the immunoexpression of cholesterol side-chain cleavage cytochrome P450 in the follicles and a decrease of 3β-hydroxysteroid dehydrogenase. After denervation, plasma levels of LH, P
4
, A
4
, T, oestrone and oestradiol-17β were lower (P < 0.05–0.001) on the particular days of the study than in the control group. Our data revealed that the denervation of ovaries during the middle luteal phase of the oestrous cycle in gilts caused distinct changes in both the morphology and the steroidogenic activity of the organ, confirming an important role of the peripheral nervous system in the control of the gonad in this species.
Planter Aid for Heavy Residue Conservation Tillage Systems
Authors: Torbert H. A. , Ingram J. T. , Prior S. A.
Published: February 2007

The use of conservation tillage systems has many crop production advantages. However, plant residue left on the soil surface makes planting the crop more difficult. One potential problem is that standing residue often gets caught in the moving mechanisms of the planter, causing the planter to become clogged. To overcome this constraint, a forward residue mover was constructed. The forward residue mover pushes the standing residue away from the planter and prevents entanglement in the row cleaner mechanism. The device is constructed of a rigid steel frame and uses attached flexible hoses to move the standing residue away from the moving mechanism of the planter as it travels across the field. A description of the forward residue mover is given. Use of this device greatly improves planter performance by preventing clogging of the moving parts of the planter.
Switchgrass and Soil Carbon Sequestration Response to Ammonium Nitrate, Manure, and Harvest Frequency on Conservation Reserve Program Land
Authors: Lee D. K. , Owens V. N. , Doolittle J. J.
Published: February 2007

Conservation Reserve Program (CRP) land on which perennial warm‐season grasses are grown could be a resource for bioenergy feedstock production and C sequestration. A 4‐yr field experiment was conducted to determine the response of switchgrass (Panicum virgatum L.) and soil C sequestration to N fertility and harvest frequency on switchgrass‐dominated CRP land in eastern South Dakota. Soil at the site is an Egan silty clay loam. Three N rates (0, 112, and 224 kg ha−1) were applied as NH4NO3 (NH4NO3–N) and cattle (Bos taurus L.) manure (manure‐N). Switchgrass was harvested at anthesis every year (EY) or alternate years (AY) from 2001 to 2004. Soil samples were collected before starting the experiment (fall 2000) and after 4 yr (fall 2004) to determine C sequestration. Averaged across N rate, the proportion of switchgrass was higher with manure‐N (64.7%) than NH4NO3‐N (46.8%). Total (switchgrass plus other herbaceous material) biomass production tended to be higher when harvested EY (average 5.0 Mg ha−1 yr−1) compared with AY (average 4.0 Mg ha−1 yr−1). However, by 2004, the proportion of switchgrass was 75% higher in plots harvested AY compared with those harvested EY. The concentration of structural components was greater in biomass harvested AY, whereas total N and ash tended to be lower. Total‐N and ash concentrations in biomass were higher with NH4NO3‐N than manure‐N. Soil C was sequestered at a rate of 2.4 ± 0.9 and 4.0 ± 1.0 Mg C ha−1 yr−1 at the 0‐ to 90‐cm depth with NH4NO3–N and manure‐N, respectively. There were no changes in soil organic C without N fertilization. Manure could be used as an alternate N source for switchgrass biomass production on CRP land with an added benefit of increased C sequestration.
The Value to Herbivores of Plant Physical and Chemical Diversity in Time and Space
Authors: Provenza F. D. , Villalba J. J. , Haskell J. , MacAdam J. W. , Griggs T. C. , Wiedmeier R. D.
Published: February 2007

Whether foraging on pastures or rangelands, herbivores encounter plant species that differ in their concentrations of nutrients. They also all contain various secondary compounds that at too high doses can be toxic, but at the appropriate dose many of these toxins may have medicinal benefits. The quantity of forage an animal consumes depends on the other forages it selects because nutrients and toxins interact. Food intake also depends on an individual's morphology and physiology, and marked variation is common, even among closely related animals, in needs for nutrients and abilities to cope with toxins. Thus, individuals can better meet their needs when offered a variety of foods that differ in nutrients and toxins than when constrained to a single food. Nonetheless, we have focused on a few species, often grown in monoculture, and we have reduced concentrations of secondary compounds with little appreciation for their roles in protecting plants against herbivores, pathogens, and competitors. In nature, where diversity of plants is the rule and not the exception, eating a variety of foods is how animals cope with, and may benefit from, secondary compounds. The potential benefits of creating mixtures of plant species whose nutrient and secondary compound profiles complement one another are obvious, though much remains to be learned about how to reconstruct agro‐ecosystems with plants that complement and enhance one another structurally, functionally, and biochemically.
Partial 13C and 15N Chemical‐Shift Assignments of the Disulfide‐Bond‐Forming Enzyme DsbB by 3D Magic‐Angle Spinning NMR Spectroscopy
Authors: Li Ying , Berthold Deborah A. , Frericks Heather L. , Gennis Robert B. , Rienstra Chad M.
Published: February 2007

DsbB is a 20 kDa Escherichia coli inner‐membrane protein that catalyzes disulfide‐bond formation in periplasmic proteins. We report highly resolved, multidimensional magic‐angle spinning NMR spectra at 750 MHz 1H frequency, which enable partial 13C and 15N chemical‐shift assignments of the signals. The narrow line widths observed indicate excellent microscopic order of the protein sample, suitable for full structure determination by solid‐state NMR. Experiments were performed exclusively on uniformly 13C,15N‐labeled DsbB. Chemical‐shift‐correlation experiments based on dipolar transfer yielded strong signals in the 3D spectra, many of which have been site‐specifically assigned to the four transmembrane helices of DsbB. Significant numbers of additional residues have been assigned to stretches of amino acids, although not yet placed in the amino acid sequence. We also report the temperature dependence of signal intensities from −50 °C to 0 °C, a range over which samples of DsbB are highly stable. Structural and dynamic information derived from SSNMR studies can give insight into DsbB in a state that so far has not been successfully crystallized.
Intramolecular Excimer Formation and Delayed Fluorescence in Sterically Constrained Pyrene Dimers
Authors: Benniston Andrew C. , Harriman Anthony , Howell Sarah L. , Sams Craig A. , Zhi Yong‐Gang
Published: February 2007

The synthesis is described for a series of five molecular dyads comprising pyrene‐based terminals covalently linked through a 1,3‐disubstituted phenylene spacer. The extent of through‐space communication between the pyrene units is modulated by steric interactions imposed by bulky moieties attached at the 6,8‐positions of each pyrene unit. For the control compound, only hydrogen atoms occupy the 6,8 positions (DP1), whereas the remaining compounds incorporate ethynylene groups terminated with either triisopropylsilyl (DP2), 1‐tert‐butylbenzene (DP3), 2,6‐di‐tert‐butylbenzene (DP4) or 1‐tert‐butyl‐3,5‐dimethylbenzene (DP5) units. Each compound shows a mixture of monomer and excimer fluorescence in fluid solution at room temperature, but only monomer emission in a glassy matrix at 77 K. The ratio of monomer to excimer fluorescence depends markedly on the molecular structure; DP1 is heavily biased in favour of the excimer and DP4 is enriched with monomer fluorescence. Photophysical properties, including laser induced and delayed fluorescence data, are reported for each compound. Delayed fluorescence occurs by both intramolecular and bimolecular steps, but these events take place on different timescales. The possibility is raised for using intramolecular triplet–triplet annihilation as a means of molecular imaging.
Obsessive‐compulsive characteristics in women who have recovered from bulimia nervosa
Authors: Morgan Jessica C. , Wolfe Barbara E. , Metzger Eran D. , Jimerson David C.
Published: February 2007

Objective:

The goal of this study was to follow up on reports that obsessive‐compulsive characteristics, which are commonly elevated in bulimia nervosa (BN), may also be elevated in individuals who have recovered from BN (BN‐R).

Method:

Self‐ratings on the Maudsley Obsessional‐Compulsive Inventory (MOCI), the Restraint Scale (a measure of dieting behavior related to weight concerns), and questionnaires reflecting eating disorder‐related symptoms were evaluated for women who met criteria for BN (n = 25) or BN‐R (n = 21) and were free of obsessive‐compulsive disorder, and for healthy female controls (n = 28).

Results:

MOCI scores for the BN‐R group (5.5 ± 5.4) were similar to those for the BN group (5.4 ± 4.4) and were significantly elevated (p < 0.05, p < 0.02, respectively) in comparison to controls (2.5 ± 1.9). Of note, MOCI scores for the BN‐R group were significantly correlated with scores on the Restraint Scale (r = 0.60, p < 0.02).

Conclusion:

Further studies are needed to assess the relationship between elevated obsessive‐compulsive characteristics and eating patterns in individuals recovered from BN. © 2007 by Wiley Periodicals, Inc. Int J Eat Disord 2007
Selective cholinergic depletion of the hippocampus spares both behaviorally induced Arc transcription and spatial learning and memory
Authors: Fletcher Bonnie R. , Baxter Mark G. , Guzowski John F. , Shapiro Matthew L. , Rapp Peter R.
Published: February 2007

We demonstrated previously that when hippocampal‐dependent learning and plasticity are compromised by fornix lesions, behaviorally induced expression of the immediate early gene, Arc, is correspondingly low. The medial septum and the vertical diagonal band are major sources of subcortical afferents that innervate the hippocampus via the fornix. Here we assessed the specific contribution of cholinergic afferents from these regions to the impairments in spatial learning and behavioral induction of Arc transcription produced by fornix lesions. The immunotoxin, 192 IgG‐saporin, was used to produce selective lesions of cholinergic cell bodies in the medial septum and vertical diagonal band. Rats were then trained on both cued and spatial delayed match‐to‐place tasks in a radial arm water maze. Animals with 192 IgG‐saporin lesions learned both cue and place discrimination tasks in the water maze normally, and showed only a mild and transient impairment when switching from the cued to the spatial version of the task. Following behavioral testing, rats explored two novel environments sequentially in a setting known to induce Arc expression in hippocampal pyramidal neurons. In marked contrast to the effects of complete fornix transection, quantitative in situ autoradiography revealed no differences in Arc mRNA expression between sham and lesion animals in CA1, CA3 or stratum radiatum. The conclusion from these data is that cholinergic deafferentation alone cannot account for the spatial learning deficits or impaired behavioral induction of Arc transcription produced by fornix lesions. © 2007 Wiley‐Liss, Inc.
Study of Ethylene‐Propylene‐1‐Hexene Co‐ and Terpolymers Obtained with Homogeneous and Supported Metallocene Catalysts
Authors: Galland Griselda Barrera , dos Santos João Henrique Zimnoch , Dall'Agnol Maiara , Bisatto Rubens
Published: February 2007

Ethylene‐propylene‐1‐hexene terpolymers were obtained using three metallocenic systems: Cp2ZrCl2, Cp2ZrCl2 directly supported on silica (Cp2ZrCl2/SiO2) and Cp2ZrCl2 supported on MAO (methylaluminoxane)‐modified silica (Cp2ZrCl2/MAO/SiO2). The results were compared with those obtained with rac‐Et[Ind]2ZrCl2. The best activities were obtained with the Cp2ZrCl2 in the homogeneous form, but the system Cp2ZrCl2/MAO/SiO2 afforded also good results. Those systems showed to be able to incorporate enough comonomers, in a randomic way, to give terpolymers with an elastomeric behaviour.
Mechanistic events underlying odorant binding protein chemoreception
Authors: Golebiowski Jérôme , Antonczak Serge , Fiorucci Sébastien , Cabrol‐Bass Daniel
Published: February 2007

Odorant binding proteins (OBP's) are small hydrophilic proteins, belonging to the lipocalin family dedicated to bind and transport small hydrophobic ligands. Despite many works, the mechanism of ligand binding, together with the functional role of these proteins remains a topic of debate and little is known at the atomic level. The present work reports a computational study of odorants capture and release by an OBP, using both constrained and unconstrained simulations, giving a glimpse on the molecular mechanism of chemoreception. The residues at the origin of the regulation of the protein door opening are identified and a tyrosine amino‐acid together with other nearby residues appear to play a crucial role in allowing this event to occur. The simulations reveal that this tyrosine and the protein's L5 loop are implicated in the ligand contact with the protein and act as an anchoring point for the ligand. The protein structural features required for the ligand entry are highly conserved among many transport proteins, suggesting that this mechanism could somewhat be extended to some members of the larger family of lipocalin. Proteins 2007. © 2007 Wiley‐Liss, Inc.
Relaxation processes of transient current in nano‐contact system: effects of electrode
Authors: Ishii Hiroyuki , Tomita Yoko , Nakayama Takashi
Published: February 2007

A new calculation method of current dynamics was developed based on the Liouville equation of density matrix and was applied to investigate the transient current when the voltage is suddenly applied to the nano‐contact systems. We found the characteristic relaxation and oscillation in transient current. The relaxation occurs due to the electron dissipation into a number of electronic states in electrodes and the relaxation speed reflects the coupling magnitude between the electrode and the nano‐system. On the other hand, the oscillation originates from the quantum‐phase interference of currents between the electrode and the nano‐system and the oscillation period reflects the energy difference between the Fermi energy of electrode and the electronic levels of nano‐system. When the bandwidth of electrode decreases, the oscillation period receives a modulation reflecting the band‐edge energies and the oscillation damping is suppressed. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Low‐energy electronic properties of a pair of carbon nanotubes
Authors: Lien Jiun‐Yi , Lin Min‐Fa
Published: February 2007

A pair of carbon nanotubes, with the intertube interactions, are studied for the low‐energy electronic properties within the tight‐binding model. Energy dispersion, state degeneracy, subband spacing, energy gaps, and density of states are dominated by the nanotube radius and the relative azimuthal angle between two nanotubes. The intertube interactions could destroy double degeneracy. Moreover, they could effectively reduce energy gaps, or change narrow‐gap systems into gapless systems. The above‐mentioned electronic properties are strongly modulated by the transverse electric field. Such a field could induce new band‐edge states. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Controlled optical switching in DMS quantum dots
Authors: Marques G. E. , López‐Richard V. , Prado S. J. , Alcalde A. M. , Trallero Giner C.
Published: February 2007

We have explored an exchange‐induced property of the electronic structure of diluted magnetic semiconductor quantum dots in order to propose an externally controlled optical switching device. Various confinement shapes, dot sizes and host material compositions are used in order to optimize the device operation. This excitonic optical switching can be established within well defined temperature and magnetic composition ranges. We are proposing a method for the implementation of this optical device that can be switched between two well‐defined regimes. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)