bluuebunny/crossref_metadata_2025 huggingface dataset:
Wanna Dance? How Firms and Underwriters Choose Each Other
Authors: FERNANDO CHITRU S. , GATCHEV VLADIMIR A. , SPINDT PAUL A.
Published: September 2005

We develop and test a theory explaining the equilibrium matching of issuers and underwriters. We assume that issuers and underwriters associate by mutual choice, and that underwriter ability and issuer quality are complementary. Our model implies that matching is positive assortative, and that matches are based on firms' and underwriters' relative characteristics at the time of issuance. The model predicts that the market share of top underwriters and their average issue quality varies inversely with issuance volume. Various cross‐sectional patterns in underwriting spreads are consistent with equilibrium matching. We find strong empirical confirmation of our theory.
The Market Impact of Trends and Sequences in Performance: New Evidence
Authors: DURHAM GREGORY R. , HERTZEL MICHAEL G. , MARTIN J. SPENCER
Published: September 2005

Bloomfield and Hales (2002) find strong evidence that experimental market subjects are influenced by trends and patterns in a manner supportive of the shifting regimes model of Barberis, Shleifer, and Vishny (1998). We subject the model to further empirical scrutiny using the football wagering market as our price laboratory. Sports betting markets have several advantages over traditional capital markets as an empirical setting, and commonalities with traditional markets allow for useful insights. We find scant evidence that investors behave in accordance with the model.
The management of dry skin with topical emollients – recent perspectives
Authors: Proksch Ehrhardt , Lachapelle Jean‐Marie
Published: September 2005

Dry skin (xerosis) is a common symptom of a number of chronic skin diseases, such as atopic dermatitis, but can also be caused by environmental factors, such as cold weather and frequent showering. The condition can cause unsightliness of the skin, discomfort, itching, and can have a negative impact on patients' quality of life. This article will cover recent developments in the understanding of xerosis and its management with emollients. The stratum corneum consists of corneocytes and lipid‐enriched intercellular bilayers. These are both produced from keratinocytes in a process called epidermal differentiation. Disturbed epidermal differentiation, resulting in the impairment of stratum corneum intercellular lipid bilayers and natural moisturizing factor, is the root cause of xerosis. The constituent ingredients of emollients should, therefore, address the different factors that contribute to dry skin and, most importantly, attempt to restore epidermal differentiation. The use of lipids, physiological lipids, humectants and antipruritics will help to restore the lipid lamellae, improve skin hydration, skin elasticity and prevent itching. The ideal emollient will include these ingredients plus an agent to support epidermal differentiation. Selecting the correct emollient product and using it regularly are vital factors in the management of xerosis.
„Lues maligna” bei insulinpflichtigem Diabetes mellitus
Authors: Hofmann Uta B. , Hund Martina , Bröcker Eva‐Bettina , Hamm Henning
Published: September 2005

Bei einer 40‐jährige Patientin mit insulinpflichtigem Diabetes mellitus traten innerhalb weniger Wochen vor allem am Stamm multiple bis 2,5 cm große, lividrote Knoten und Plaques auf, die rasch ulzerierten. Einige Monate zuvor habe beim Partner ein kleines Ulkus am Penis bestanden. Die HIV‐negative Patientin hatte eine hochtitrig positive Syphilisserologie (TPPA‐Titer > 1 : 20.480, VDRL‐Titer 1 : 128). Die nüchtern Blutglukosewerte lagen über 275 mg/dl. Nach Ausschluss einer Neurolues stellten wir die Diagnose einer „Lues maligna” bei schlecht eingestelltem Diabetes mellitus. Unter einer Therapie mit 3 Injektionen Benzylpenicillin‐Benzathin (2,4 Mio. IE) i. m. in wöchentlichen Abständen und Einstellung des Diabetes heilten die Hautveränderungen komplett ab. Im Verlauf war der VDRL‐Titer negativ.

Die „Lues maligna” tritt seit einigen Jahren wieder gehäuft auf und wird vor allem bei HIV‐positiven Männern beobachtet. Das Auftreten dieser Erkrankung bei durch Diabetes mellitus bedingter Immunsuppression ist ausgesprochen selten.
Crystal structure of the soluble form of the redox‐regulated chloride ion channel protein CLIC4
Authors: Littler Dene R. , Assaad Nagi N. , Harrop Stephen J. , Brown Louise J. , Pankhurst Greg J. , Luciani Paolo , Aguilar Marie‐Isabel , Mazzanti Michele , Berryman Mark A. , Breit Samuel N. , Curmi Paul M. G.
Published: September 2005

The structure of CLIC4, a member of the CLIC family of putative intracellular chloride ion channel proteins, has been determined at 1.8 Å resolution by X‐ray crystallography. The protein is monomeric and it is structurally similar to CLIC1, belonging to the GST fold class. Differences between the structures of CLIC1 and CLIC4 are localized to helix 2 in the glutaredoxin‐like N‐terminal domain, which has previously been shown to undergo a dramatic structural change in CLIC1 upon oxidation. The structural differences in this region correlate with the sequence differences, where the CLIC1 sequence appears to be atypical of the family. Purified, recombinant, wild‐type CLIC4 is shown to bind to artificial lipid bilayers, induce a chloride efflux current when associated with artificial liposomes and produce an ion channel in artificial bilayers with a conductance of 30 pS. Membrane binding is enhanced by oxidation of CLIC4 while no channels were observed via tip‐dip electrophysiology in the presence of a reducing agent. Thus, recombinant CLIC4 appears to be able to form a redox‐regulated ion channel in the absence of any partner proteins.
Serpins 2005 – fun between the β‐sheets
Authors: Whisstock James C. , Bottomley Stephen P. , Bird Phillip I. , Pike Robert N. , Coughlin Paul
Published: September 2005

Serpins are the largest family of protease inhibitors and are fundamental for the control of proteolysis in multicellular eukaryotes. Most eukaryote serpins inhibit serine or cysteine proteases, however, noninhibitory members have been identified that perform diverse functions in processes such as hormone delivery and tumour metastasis. More recently inhibitory serpins have been identified in prokaryotes and unicellular eukaryotes, nevertheless, the precise molecular targets of these molecules remains to be identified. The serpin mechanism of protease inhibition is unusual and involves a major conformational rearrangement of the molecule concomitant with a distortion of the target protease. As a result of this requirement, serpins are susceptible to mutations that result in polymerization and conformational diseases such as the human serpinopathies. This review reports on recent major discoveries in the serpin field, based upon presentations made at the 4th International Symposium on Serpin Structure, Function and Biology (Cairns, Australia).
Molecular characterization and expression of caprine (Capra hircus) interleukin‐18 cDNA
Authors: Hosamani M. , Mondal B. , Muneta Y. , Rasool T. J.
Published: September 2005

Interleukin 18 (IL‐18) has been identified as a potent upstream cytokine required for upregulation of IFN‐γ secretion that plays a crucial role in polarization of Th1 type of immune response. Considering the potential applications of the cytokine in immunomodulation, it has been characterized in many livestock species including cattle, equines, canines, felines and porcines. In this paper we report the isolation, cloning sequencing and expression of caprine precursor IL‐18. Full‐length caprine IL‐18 cDNA was isolated from mitogen‐stimulated adherent peripheral blood mononuclear cells using reverse transcription polymerase chain reaction (RT‐PCR). The cDNA contained an open reading frame of 579 bp encoding a putative polypeptide of 192 amino acids. Deduced amino acid sequence of caprine IL‐18 showed varying amino acid identity with the published sequences of other domestic ruminant species ranging from 94.3% to 96.9%, while it shared over 78% aa identity with other domestic animals. Pairwise multiple aligned sequences showed a deletion of Glu31in caprine IL‐18 unlike in other species. Recombinant caprine IL‐18 was produced in Escherichia coli, which cross‐reacted with two antiporcine IL‐18 monoclonal antibodies.
Long‐term in vivo modulation of synaptic efficacy at the neuromuscular junction of Rana pipiens frogs
Authors: Bélair Eve‐Lyne , Vallée Joanne , Robitaille Richard
Published: September 2005

Prolonged changes in motor neurone activity can result in long‐term changes in synaptic transmission. We investigated whether mechanisms commonly thought to be involved in determining synaptic efficacy of vertebrate motor neurones are involved in these long‐term changes. The nerve supplying the cutaneus pectoris muscle was chronically stimulated via skin surface electrodes in freely moving frogs for 5–7 days. Chronic stimulation induced a 50% reduction in evoked endplate potential (EPP) amplitude at stimulated neuromuscular junctions (NMJs). These changes appear to be presynaptic since miniature EPP (mEPP) amplitude was unchanged while mEPP frequency was decreased by 46% and paired‐pulse facilitation was increased by 26%. High frequency facilitation (40 Hz, 2 s) was also increased by 89%. Moreover, stimulated NMJs presented a 92% decrease in synaptic depression (40 Hz, 2 s). An increase in mitochondrial metabolism was observed as indicated by a more pronounced labelling of active mitochondria (Mitotracker) in stimulated nerve terminals, which could account for their greater resistance to synaptic depression. NMJ length visualized by α‐bungarotoxin staining of nAChRs was not affected. Presynaptic calcium signals measured with Calcium Green‐1 were larger in stimulated NMJs at low frequency (0.2 Hz) and not different from control NMJs at higher frequency (40 Hz, 2 s and 30 s). These results suggest that some mechanisms downstream of calcium entry are responsible for the determination of synaptic output, such as a down‐regulation of some calcium‐binding proteins, which could explain the observed results. The possibility of a change in frequenin expression, a calcium‐binding protein that is more prominently expressed in phasic synapses, was, however, refuted by our results.
A maskless photolithographic prototyping system using a low-cost consumer projector and a microscope
Authors: Musgraves J. David , Close Brett T. , Tanenbaum David M.
Published: September 2005

Lithographic processing has been the key technology responsible for the rapid advances in microelectronics, but is typically not accessible to undergraduates. We have developed a maskless photolithographic system that can be assembled from a consumer projector and a trinocular microscope. This system allows students to design and print custom patterns into photoresist in less than 30 min, without using a clean room, a mask facility, or a chrome-etch bath. Students can create and evaluate patterns, make changes to their design, or add additional layers of aligned patterns in a single laboratory session. The rapid turnaround time and low cost of ownership is useful for low-resolution (∼10 μm) prototyping. Photoresist is spun in a modified food processor and baked on a standard hot plate. Mating pieces were machined from aluminum. Only the digital light processing projector and food processor are modified, so the microscope, camera, and computer need not be dedicated to the system. The entire system can be assembled for less than $5000.
Analytical results for a Fokker–Planck equation in the small noise limit
Authors: Lutz Eric
Published: September 2005

We present analytical results for the lowest order cumulants of a stochastic process described by a Fokker–Planck equation with nonlinear drift, which appears in the description of laser cooling of atoms. We show that, in the limit of small fluctuations, the mean, the variance, and the covariance of the process can be expressed in compact form with the help of the Lambert W function. As an application, we discuss the interplay of noise and nonlinearity far from equilibrium.
Damping in a variable mass on a spring pendulum
Authors: Digilov Rafael M. , Reiner M. , Weizman Z.
Published: September 2005

A model of damped oscillations of a variable mass on a spring pendulum, with the mass decreasing at a constant rate is presented. The model includes damping terms that are linear and quadratic in the velocity. The effect of the mass loss rate on the magnitude of the damping parameters is discussed. The model is compared to experimental data obtained with the aid of computer-based laboratory equipment.
Snell’s law from an elementary particle viewpoint
Authors: Drosdoff D. , Widom A.
Published: September 2005

Snell’s law for the path of light between media with different indices of refraction is usually discussed in terms of Maxwell’s electromagnetic wave theory. Snell’s law also may be derived from a photon beam theory of light rays. We show that this particle physics view is much simpler for understanding the laws of refraction.
Hanbury Brown Twiss Effect for Ultracold Quantum Gases
Authors: Schellekens M. , Hoppeler R. , Perrin A. , Gomes J. Viana , Boiron D. , Aspect A. , Westbrook C. I.
Published: September 2005

We have studied two-body correlations of atoms in an expanding cloud above and below the Bose-Einstein condensation threshold. The observed correlation function for a thermal cloud shows a bunching behavior, whereas the correlation is flat for a coherent sample. These quantum correlations are the atomic analog of the Hanbury Brown Twiss effect. We observed the effect in three dimensions and studied its dependence on cloud size.
The Dust Grains from 9P/Tempel 1 Before and After the Encounter with Deep Impact
Authors: Harker David E. , Woodward Charles E. , Wooden Diane H.
Published: September 2005

Gemini-N observed the properties of dust ejected from the nucleus of comet 9P/Tempel 1 before and after its encounter with Deep Impact. Marked changes were seen in the 7.8- to 13-micrometer spectral energy distribution and derived grain properties of the inner coma. A strong, broad silicate feature dominated by emission from amorphous pyroxene, amorphous olivine, and magnesium-rich crystalline olivine had developed by 1 hour after impact. The ejected dust mass is ≅10
4
to 10
6
kilograms on the basis of our models. Twenty-six hours later the silicate feature had faded, leaving a smooth featureless spectrum, similar to that observed before the impact, suggesting that the impact did not produce a new active region releasing small particles on the nucleus.
Parent Volatiles in Comet 9P/Tempel 1: Before and After Impact
Authors: Mumma Michael J. , DiSanti Michael A. , Magee-Sauer Karen , Bonev Boncho P. , Villanueva Geronimo L. , Kawakita Hideyo , Russo Neil Dello , Gibb Erika L. , Blake Geoffrey A. , Lyke James E. , Campbell Randall D. , Aycock Joel , Conrad Al , Hill Grant M.
Published: September 2005

We quantified eight parent volatiles (H
2
O, C
2
H
6
, HCN, CO, CH
3
OH, H
2
CO, C
2
H
2
, and CH
4
) in the Jupiter-family comet Tempel 1 using high-dispersion infrared spectroscopy in the wavelength range 2.8 to 5.0 micrometers. The abundance ratio for ethane was significantly higher after impact, whereas those for methanol and hydrogen cyanide were unchanged. The abundance ratios in the ejecta are similar to those for most Oort cloud comets, but methanol and acetylene are lower in Tempel 1 by a factor of about 2. These results suggest that the volatile ices in Tempel 1 and in most Oort cloud comets originated in a common region of the protoplanetary disk.
Short term effects of particulate matter on cause specific mortality: effects of lags and modification by city characteristics
Authors: Zeka A , Zanobetti A , Schwartz J
Published: September 2005

Background:Consistent evidence has shown increased all-cause mortality, and mortality from broad categories of causes associated with airborne particles. Less is known about associations with specific causes of death, and modifiers of those associations.

Aims:To examine these questions in 20 US cities, between 1989 and 2000.

Methods:Mortality files were obtained from the National Center for Health Statistics. Air pollution data were obtained from the Environmental Protection Agency website. The associations between daily concentrations of particulate matter of aero-diameter ⩽10 μm (PM10) and daily mortality from all-cause and selected causes of death, were examined using a case-crossover design. Temporal effects of PM10were examined using lag models, in first stage regressions. City specific modifiers of these associations were examined in second stage regressions.

Results:All-cause mortality increased with PM10exposures occurring both one and two days prior the event. Deaths from heart disease were primarily associated with PM10on the two days before, while respiratory deaths were associated with PM10exposure on all three days. Analyses using only one lag underestimated the effects for all-cause, heart, and respiratory deaths. Several city characteristics modified the effects of PM10on daily mortality. Important findings were seen for population density, percentage of primary PM10from traffic, variance of summer temperature, and mean of winter temperature.

Conclusions:There was overall evidence of increased daily mortality from increased concentrations of PM10that persisted across several days, and matching for temperature did not affect these associations. Heterogeneity in the city specific PM10effects could be explained by differences in certain city characteristics.
MANAGING INTERINDUSTRY DIFFERENCES THROUGH DYNAMIC CAPABILITIES: THE CASE STUDY OF NOKIA
Authors: BHUTTO ARABELLA
Published: September 2005

This paper examines the case of Nokia as a player of the mobile communication industry and provider of mobile communication system: Mobile handsets (consumer goods) and mobile networks (CoPS). Our aim is to analyze the impact of strategic management and dynamic capability developed by a firm of such an industry, which supports the entire system and manages inter-industry differences of consumer goods and CoPS. Recent convergence among technologies has raised competition among firms. Achieving and sustaining competitive advantage in this converging market is therefore possible by identifying threats and then developing strategies and capabilities to resolve them. This article concludes by examining how the firm can achieve its competitive advantage.
INTERROGATING RACISM: Toward an Antiracist Anthropology
Authors: Mullings Leith
Published: September 2005

Over the past several decades, global manifestations of racism have undergone significant transformations. The anticolonial struggle, the civil rights movement, and the antiapartheid offensive have challenged the former established racial regimes. But the consolidation of global capitalism has also created new forms of racialization. A variety of antiracist strategies and interventions have emerged to confront new racisms. Analyses of racism have sought to interrogate its history and contemporary manifestations, how it is maintained and reproduced, and to predict its future. Anthropologists and other social scientists are challenged to develop theoretical perspectives and methodological approaches to advance our understanding of these new manifestations of race and racism.
SOCIAL AND CULTURAL POLICIES TOWARD INDIGENOUS PEOPLES: Perspectives from Latin America
Authors: Peña Guillermo de la
Published: September 2005

Throughout the twentieth century, social and cultural policies toward indigenous peoples in Latin America have been closely related to indigenismo, an ideological movement that denounced the exploitation of aboriginal groups and strove for the cultural unity and the extension of citizenship through social integration and “acculturation.” This review traces the colonial and nineteenth-century roots of indigenismo and places it in the context of the populist tendencies in most Latin American states from the 1920s to the 1970s, which favored economic protectionism and used agrarian reform and the provision of services as tools for governance and legitimacy. Also examined is the role of anthropological research in its relation to state hegemony as well as the denunciation of indigenista policies by ethnic intellectuals and organizations. In recent decades, the dismantling of populist policies has given rise to a new official “neoliberal” discourse that extols multiculturalism. However, the widespread demand for multicultural policies is also seen as the outcome of the fight by militant indigenous organizations for a new type of citizenship.
AUTOCHTHONY: Local or Global? New Modes in the Struggle over Citizenship and Belonging in Africa and Europe
Authors: Ceuppens Bambi , Geschiere Peter
Published: September 2005

The past 15 years have brought an upsurge of “autochthony.” It has become an incendiary political slogan in many parts of the African continent as an unexpected corollary of democratization and the new style of development policies (“by-passing the state” and decentralization). The main agenda of the new autochthony movements is the exclusion of supposed “strangers” and the unmasking of “fake” autochthons, who are often citizens of the same nation-state. However, Africa is no exception in this respect. Intensified processes of globalization worldwide seem to go together with a true “conjuncture of belonging” (T.M. Li 2000 ) and increasingly violent attempts to exclude “allochthons.” This article compares studies of the upsurge of autochthony in Africa with interpretations of the rallying power of a similar discourse in Western Europe. How can the same discourse appear “natural” in such disparate circumstances? Recent studies highlight the extreme malleability of the apparently self-evident claims of autochthony. These discourses promise the certainty of belonging, but in practice, they raise basic uncertainties because autochthony is subject to constant redefinition against new “others” and at ever-closer range.
THE ARCHAEOLOGY OF BLACK AMERICANS IN RECENT TIMES
Authors: Leone Mark P. , LaRoche Cheryl Janifer , Babiarz Jennifer J.
Published: September 2005

A review of work on African Americans through archaeology takes place under diasporic studies and relies on literature that defines the North American black experience. The focus is on the establishment of freedom by the founding of maroon communities and independent settlements of free people, as well as on the use and interpretation of African diasporic history and theory, particularly by archaeologists using knowledge of the diaspora to effect modern political change.
THE ANTHROPOLOGY OF THE BEGINNINGS AND ENDS OF LIFE
Authors: Kaufman Sharon R. , Morgan Lynn M.
Published: September 2005

This essay reviews recent anthropological attention to the “beginnings” and “endings” of life. A large literature since the 1990s highlights the analytic trends and innovations that characterize anthropological attention to the cultural production of persons, the naturalization of life, and the emergence of new life forms. Part I of this essay outlines the coming-into-being, completion and attenuation of personhood and how life and death are attributed, contested, and enacted. Dominant themes include how connections are forged or severed between the living and the dead and the socio-politics of dead, dying, and decaying bodies. The culture of medicine is examined for its role in organizing and naming life and death. Part II is organized by the turn to biopolitical analyses stimulated by the work of Foucault. It encompasses the ways in which the biosciences and biotechnologies, along with state practices, govern forms of living and dying and new forms of life such as the stem cell, embryo, comatose, and brain dead, and it emphasizes the production of value. Much of this scholarship is informed by concepts of liminality (a period and state of being between social statuses) and subjectification (in which notions of self, citizenship, life and its management are linked to the production of knowledge and political forms of regulation).
THROUGH WARY EYES: Indigenous Perspectives on Archaeology
Authors: Watkins Joe
Published: September 2005

Archaeology has been linked to colonialist attitudes and scientific imperialism. But what are the perspectives of Indigenous groups concerning the practice of archaeology? Numerous organizations recognize the distinctive needs of Indigenous communities throughout the world and have adopted agreements and definitions that govern their relationships with those populations. The specific name by which Indigenous groups are known varies from country to country, as local governments are involved in determining the appropriateness of particular definitions to populations within their borders. This paper begins with an examination of the various aspects that have been used to determine whether or not a group of people might be considered “indigenous” under various definitions, and then uses the history of the relationships between North American archaeologists and Indigenous populations as a background for the examination of some of the political aspects of archaeology that have impacted Indigenous populations. It then proceeds to discuss perspectives on archaeology offered by members of various Indigenous populations throughout the World.
LOOTING AND THE WORLD'S ARCHAEOLOGICAL HERITAGE: The Inadequate Response
Authors: Brodie Neil , Renfrew Colin
Published: September 2005

The world's archaeological heritage is under serious threat from illegal and destructive excavations that aim to recover antiquities for sale on the international market. These antiquities are sold without provenance, so that their true nature is hard to discern, and many are ultimately acquired by major museums in Europe and North America. The adoption in 1970 by UNESCO of the Convention on the Means of Prohibiting and Preventing the Illicit Import, Export and Transfer of Ownership of Cultural Property created a new ethical environment in which museums and their representative associations adopted policies that were designed to guard against the acquisition of “unprovenanced,” and therefore most probably looted, antiquities. Unfortunately, over the past decade, U.S. museum associations have been advocating a more relaxed disposition, and the broader archaeological and anthropological communities are in significant measure responsible since they have met this unwelcome development largely in silence.
CASTE AND POLITICS: Identity Over System
Authors: Gupta Dipankar
Published: September 2005

To integrate conceptually the relationship between caste and politics, one must appreciate that the pure ritual hierarchy operates only when backed by wealth and power. In fact, there are multiple hierarchies in the caste order because each caste overvalues itself in relation to others. This can be gauged from their origin tales, which, without exception, claim an exalted past regardless of the actual status a caste occupies on the ground. With the breakdown of the closed village economy and the rise of democratic politics, the competitive element embedded in caste has come to the fore. This has resulted in the collapse of the caste system but also in the rise of caste identities.
TRP CHANNELS IN C. ELEGANS
Authors: Kahn-Kirby Amanda H. , Bargmann Cornelia I.
Published: September 2005

▪ Abstract  The TRP (transient receptor potential) superfamily of cation channels is present in all eukaryotes, from yeast to mammals. Many TRP channels have been studied in the nematode Caenorhabditis elegans, revealing novel biological functions, regulatory modes, and mechanisms of localization. C. elegans TRPV channels function in olfaction, mechanosensation, osmosensation, and activity-dependent gene regulation. Their activity is regulated by G protein signaling and polyunsaturated fatty acids. C. elegans TRPPs related to human polycystic kidney disease genes are expressed in male-specific neurons. The KLP-6 kinesin directs TRPP channels to cilia, where they may interact with F0/F1 ATPases. A sperm-specific TRPC channel, TRP-3, is required for fertilization. Upon sperm activation, TRP-3 translocates from an intracellular compartment to the plasma membrane to allow store-operated Ca2+ entry. The TRPM channels GON-2 and GTL-2 regulate Mg2+ homeostasis and Mg2+ uptake by intestinal cells; GON-2 is also required for gonad development. The TRPML CUP-5 promotes normal lysosome biogenesis and prevents apoptosis. Dynamic, precise expression of TRP proteins generates a remarkable range of cellular functions.
Neuroecology
Authors: Sherry David F.
Published: September 2005

Neuroecology is the study of adaptive variation in cognition and the brain. The origin of neuroecology dates from the 1980s, when researchers in behavioral ecology began to apply the methods of comparative evolutionary biology to cognitive processes and the underlying neural mechanisms of cognition. The comparative approach, however, is much older. It was a mainstay of ethology, it has been part of the study of neuroanatomy since the seventeenth century, and it was used by Darwin to marshal evidence for the theory of natural selection. Neuroecology examines the relations between ecological selection pressures and species or sex differences in cognition and the brain. The goal of neuroecology is to understand how natural selection acts on cognition and its neural mechanisms. This chapter describes the general approach of neuroecology, phylogenetic comparative methods used in the field, and new findings on the cognitive mechanisms and brain structures involved in mating systems, social organization, communication, and foraging. The contribution of neuroecology to psychology and the neurosciences is the information it provides on the selective pressures that have influenced the evolution of cognition and brain structure.
A PUBLIC HEALTH SUCCESS: Understanding Policy Changes Related to Teen Sexual Activity and Pregnancy
Authors: Brindis Claire D.
Published: September 2005

▪ Abstract  Teenage pregnancy prevention has long been on the American public health agenda. Over the past decade, a number of concurrent federal, state, and local policies have responded to the myriad and diverse needs of adolescents, from supporting adolescents who have not initiated sexual intercourse to strategies aimed at avoiding a repeat pregnancy among teenage parents. Key policies, including comprehensive family life education, access to contraceptive care, and youth development, have resulted in delays in sexual debut, improved contraceptive use, and have achieved reductions in pregnancies, abortions, and births. Although improvements are documented across all ethnic and racial subgroups, substantial health disparities continue to exist. Synergistic policy approaches represent a substantial change from the past when narrow, single-issue strategies were adopted and were limited in their effectiveness. Renewed efforts to implement narrow policy approaches (e.g., abstinence-until-marriage or restrictions to contraceptive access) need to be considered in light of existing research findings.
Glucagon-like peptide-2 protects against TPN-induced intestinal hexose malabsorption in enterally refed piglets
Authors: Cottrell J. J. , Stoll B. , Buddington R. K. , Stephens J. E. , Cui L. , Chang X. , Burrin D. G.
Published: September 2005

Premature infants receiving chronic total parenteral nutrition (TPN) due to feeding intolerance develop intestinal atrophy and reduced nutrient absorption. Although providing the intestinal trophic hormone glucagon-like peptide-2 (GLP-2) during chronic TPN improves intestinal growth and morphology, it is uncertain whether GLP-2 enhances absorptive function. We placed catheters in the carotid artery, jugular and portal veins, duodenum, and a portal vein flow probe in piglets before providing either enteral formula (ENT), TPN or a coinfusion of TPN plus GLP-2 for 6 days. On postoperative day 7, all piglets were fed enterally and digestive functions were evaluated in vivo using dual infusion of enteral (13C) and intravenous (2H) glucose, in vitro by measuring mucosal lactase activity and rates of apical glucose transport, and by assessing the abundances of sodium glucose transporter-1 (SGLT-1) and glucose transporter-2 (GLUT2). Both ENT and GLP-2 pigs had larger intestine weights, longer villi, and higher lactose digestive capacity and in vivo net glucose and galactose absorption compared with TPN alone. These endpoints were similar in ENT and GLP-2 pigs except for a lower intestinal weight and net glucose absorption in GLP-2 compared with ENT pigs. The enhanced hexose absorption in GLP-2 compared with TPN pigs corresponded with higher lactose digestive and apical glucose transport capacities, increased abundance of SGLT-1, but not GLUT-2, and lower intestinal metabolism of [13C]glucose to [13C]lactate. Our findings indicate that GLP-2 treatment during chronic TPN maintains intestinal structure and lactose digestive and hexose absorptive capacities, reduces intestinal hexose metabolism, and may facilitate the transition to enteral feeding in TPN-fed infants.
Feline lower esophageal sphincter sling and circular muscles have different functional inhibitory neuronal responses
Authors: L'Heureux Marie-Claude , Muinuddin Ahmad , Gaisano Herbert Y. , Diamant Nicholas E.
Published: September 2005

The lower esophageal sphincter (LES) has a circular muscle component exhibiting spontaneous tone that is relaxed by nitric oxide (NO) and a low-tone sling muscle that contracts vigorously to cholinergic stimulation but with little or no evidence of NO responsiveness. This study dissected the responses of the sling muscle to nitrergic innervation in relationship to its cholinergic innervation and circular muscle responses. Motor responses were induced by electrical field stimulation (EFS; 1–30 Hz) of muscle strips from sling and circular regions of the feline LES in the presence of cholinergic receptor inhibition (atropine) or NO synthase inhibition [ NG-nitro-l-arginine (l-NNA) ± atropine]. This study showed the following. First, sling muscle developed less intrinsic resting tone compared with circular muscle. Second, with EFS, sling muscle contracted (most at ≤10 Hz), whereas circular muscle relaxed >50% by 5 Hz. Third, on neural blockade with atropine or l-NNA ± atropine, 1) sling muscle, although predominantly influenced by excitatory cholinergic stimulation, had a small neural NO-mediated inhibition, with no significant non-NO-mediated inhibition and 2) circular muscle, although little affected by cholinergic influence, underwent relaxation predominantly by neural release of NO and some non-NO inhibitory influence (at higher EFS frequency). Fourth, the sling, precontracted with bethanecol, could relax with NO and some non-NO inhibition. Finally, the tension range of both muscles is similar. In conclusion, sling muscle has limited NO-mediated inhibition to potentially augment or replace sling relaxation effected by switching off its cholinergic excitation. Differences within the LES sling and circular muscles could provide new directions for therapy of LES disorders.
Skeletal muscle ATP turnover and muscle fiber conduction velocity are elevated at higher muscle temperatures during maximal power output development in humans
Authors: Gray Stuart R. , De Vito Giuseppe , Nimmo Myra A. , Farina Dario , Ferguson Richard A.
Published: September 2005

The effect of temperature on skeletal muscle ATP turnover and muscle fiber conduction velocity (MFCV) was studied during maximal power output development in humans. Eight male subjects performed a 6-s maximal sprint on a mechanically braked cycle ergometer under conditions of normal (N) and elevated muscle temperature (ET). Muscle temperature was passively elevated through the combination of hot water immersion and electric blankets. Anaerobic ATP turnover was calculated from analysis of muscle biopsies obtained before and immediately after exercise. MFCV was measured during exercise using surface electromyography. Preexercise muscle temperature was 34.2°C (SD 0.6) in N and 37.5°C (SD 0.6) in ET. During ET, the rate of ATP turnover for phosphocreatine utilization [temperature coefficient (Q10) = 3.8], glycolysis (Q10= 1.7), and total anaerobic ATP turnover [Q10= 2.7; 10.8 (SD 1.9) vs. 14.6 mmol·kg−1(dry mass)·s−1(SD 2.3)] were greater than during N ( P < 0.05). MFCV was also greater in ET than in N [3.79 (SD 0.47) to 5.55 m/s (SD 0.72)]. Maximal power output (Q10= 2.2) and pedal rate (Q10= 1.6) were greater in ET compared with N ( P < 0.05). The Q10of maximal and mean power were correlated ( P < 0.05; R = 0.82 and 0.85, respectively) with the percentage of myosin heavy chain type IIA. The greater power output obtained with passive heating was achieved through an elevated rate of anaerobic ATP turnover and MFCV, possibly due to a greater effect of temperature on power production of fibers, with a predominance of myosin heavy chain IIA at the contraction frequencies reached.
Altered arachidonic acid metabolism impairs functional vasodilation in metabolic syndrome
Authors: Xiang Lusha , Naik Jay S. , Hodnett Benjamin L. , Hester Robert L.
Published: September 2005

These studies tested the hypothesis that in obese Zucker rats (OZRs), a model of metabolic syndrome, the impaired functional vasodilation is due to increased thromboxane receptor (TP)-mediated vasoconstriction and/or decreased prostacyclin-induced vasodilation. Spinotrapezius arcade arterioles from 12-wk-old lean (LZR) and OZR were chosen for microcirculatory observation. Arteriolar diameter (5 LZR and 6 OZR) was measured after 2 min of muscle stimulation in the absence or presence of 1 μM SQ-29548 (TP antagonist). Additionally, arteriolar diameter (6 for each group) was measured after application of iloprost (prostacyclin analog; 0.28, 2.8, and 28 μM), arachidonic acid (10 μM), and sodium nitroprusside (0.1, 1, and 10 μM) in the absence or presence of 1 μM SQ-29548. A 10 μM concentration of adenosine was used to induce a maximal dilation. Basal diameters were not different between LZRs and OZRs. Functional hyperemia and arachidonic acid-mediated vasodilations were significantly attenuated in OZR compared with LZR, and treatment with 1 μM SQ-29548 significantly enhanced the dilations in OZRs, although it had no effect in LZRs. Vasodilatory responses to iloprost and sodium nitroprusside (1 and 10 μM) were significantly reduced in OZR. Adenosine-mediated vasodilation was not different between groups. These results suggest that the impaired functional dilation in the OZR is due to an increased TP-mediated vasoconstriction and a decreased PGI2-induced vasodilation.
Glucagon-like peptide-2 acutely increases proximal small intestinal blood flow in TPN-fed neonatal piglets
Authors: Stephens John , Stoll Barbara , Cottrell Jeremy , Chang Xiaoyan , Helmrath Michael , Burrin Douglas G.
Published: September 2005

Glucagon-like peptide-2 (GLP-2) is a gut hormone that is secreted in response to enteral feeding and stimulates small intestinal mucosal growth. We have previously shown that GLP-2 infusion acutely increases portal venous blood flow in TPN-fed piglets. The aim of this study was to localize the vasoactive effect of GLP-2 within the gastrointestinal tissues and other visceral organs in TPN-fed piglets. Tissue blood flow rates were quantified using fluorescent microsphere deposition in anesthetized TPN-fed piglets given intravenous infusion of GLP-2 at either 500 pmol·kg−1·h−1 (low GLP-2, n = 7 pigs) or 2,000 pmol·kg−1·h−1 (high GLP-2, n = 8 pigs) for 2 h. Compared with baseline, the low and the high GLP-2 treatment significantly increased the blood flow rate in the duodenum (+77%) and jejunum (+40% and 80%), respectively, but blood flow to the distal small intestine and colon (−15%) was unchanged or slightly decreased. Baseline mucosal blood flow was five-fold higher than serosal blood flow; however, high GLP-2 treatment increased serosal (+140%) to a larger degree than mucosal blood flow (+73%). The high GLP-2 dose increased pancreatic flow (+34%) but decreased blood flow in the kidneys (−14%) and stomach (−12%), whereas the spleen and brain were unaffected. These findings suggest that the acute GLP-2-mediated stimulation of portal blood flow in TPN-fed piglets occurs principally via increased blood flow through the superior mesenteric artery to the proximal small intestine, a tissue region where the GLP-2R mRNA abundance and trophic GLP-2 effects are greatest.
Lower skeletal muscle capillarization and VEGF expression in aged vs. young men
Authors: Ryan Nicholas A. , Zwetsloot Kevin A. , Westerkamp Lenna M. , Hickner Robert C. , Pofahl Walter E. , Gavin Timothy P.
Published: September 2005

Recently, we observed that muscle capillarization, vascular endothelial growth factor (VEGF) protein, and the VEGF mRNA response to acute exercise were lower in aged compared with young women (Croley AN, Zwetsloot KA, Westerkamp LM, Ryan NA, Pendergast aged men, Hickner RC, Pofahl WE, and Gavin TP. J Appl Physiol 99: 1875–1882, 2005). We hypothesized that similar age-related differences in muscle capillarization and VEGF expression would exist between young and aged men. Skeletal muscle biopsies were obtained from the vastus lateralis before and at 4 h after a submaximal exercise bout for the measurement of morphometry, capillarization, VEGF, KDR, and Flt-1 in seven aged (mean age 65 yr) and eight young (mean age 21 yr) sedentary men. In aged compared with young men, muscle capillary contacts and capillary-to-fiber perimeter exchange index were lower regardless of fiber type. Muscle VEGF mRNA and protein were lower in aged men both at rest and 4 h postexercise. Exercise increased muscle VEGF mRNA and protein and KDR mRNA independent of age group. There were no effects of exercise or age on muscle Flt-1 mRNA or protein or KDR protein. These results confirm that skeletal muscle capillarization and VEGF expression are lower in aged compared with young men.
High-dose benfotiamine rescues cardiomyocyte contractile dysfunction in streptozotocin-induced diabetes mellitus
Authors: Ceylan-Isik Asli F. , Wu Shan , Li Qun , Li Shi-Yan , Ren Jun
Published: September 2005

Diabetic cardiomyopathy is characterized by cardiac dysfunction. This study was designed to examine the effect of benfotiamine, a lipophilic derivative of thiamine, on streptozotocin (STZ)-induced cardiac contractile dysfunction in mouse cardiomyocytes. Adult male FVB mice were made diabetic with a single injection of STZ (200 mg/kg ip). Fourteen days later, control and diabetic (fasting plasma glucose > 13.9 mM) mice were put on benfotiamine therapy (100 mg·kg−1·day−1 ip) for another 14 days. Mechanical and intracellular Ca2+ properties were evaluated in left ventricular myocytes using an IonOptix MyoCam system. The following indexes were evaluated: peak shortening (PS), time to PS (TPS), time to 90% relengthening (TR90), maximal velocity of shortening/relengthening, resting and rise of intracellular Ca2+ in response to electrical stimulus, sarcoplasmic reticulum (SR) Ca2+ load, and intracellular Ca2+ decay rate (τ). Two- or four-week STZ treatment led to hyperglycemia, prolonged TPS and TR90, reduced SR Ca2+ load, elevated resting intracellular Ca2+ level and prolonged τ associated with normal PS, maximal velocity of shortening/relengthening, and intracellular Ca2+ rise in response to electrical stimulus. Benfotiamine treatment abolished prolongation in TPS, TR90, and τ, as well as reduction in SR Ca2+ load without affecting hyperglycemia and elevated resting intracellular Ca2+. Diabetes triggered oxidative stress, measured by GSH-to-GSSG ratio and formation of advanced glycation end product (AGE) in the hearts. Benfotiamine treatment alleviated oxidative stress without affecting AGE or protein carbonyl formation. Collectively, our results indicated that benfotiamine may rescue STZ-induced cardiomyocyte dysfunction but not AGE formation in short-term diabetes.
Cytokine Dysregulation, Inflammation and Well-Being
Authors: Elenkov Ilia J. , Iezzoni Domenic G. , Daly Adrian , Harris Alan G. , Chrousos George P.
Published: September 2005

Cytokines mediate and control immune and inflammatory responses. Complex interactions exist between cytokines, inflammation and the adaptive responses in maintaining homeostasis, health, and well-being. Like the stress response, the inflammatory reaction is crucial for survival and is meant to be tailored to the stimulus and time. A full-fledged systemic inflammatory reaction results in stimulation of four major programs: the acute-phase reaction, the sickness syndrome, the pain program, and the stress response, mediated by the hypothalamic-pituitary-adrenal axis and the sympathetic nervous system. Common human diseases such as atopy/allergy, autoimmunity, chronic infections and sepsis are characterized by a dysregulation of the pro- versus anti-inflammatory and T helper (Th)1versus Th2 cytokine balance. Recent evidence also indicates the involvement of pro-inflammatory cytokines in the pathogenesis of atherosclerosis and major depression, and conditions such as visceral-type obesity, metabolic syndrome and sleep disturbances. During inflammation, the activation of the stress system, through induction of a Th2 shift, protects the organism from systemic ‘overshooting’ with Th1/pro-inflammatory cytokines. Under certain conditions, however, stress hormones may actually facilitate inflammation through induction of interleukin (IL)-1, IL-6, IL-8, IL-18, tumor necrosis factor-α and C-reactive protein production and through activation of the corticotropin-releasing hormone/substance P-histamine axis. Thus, a dysfunctional neuroendocrine-immune interface associated with abnormalities of the ‘systemic anti-inflammatory feedback’ and/or ‘hyperactivity’ of the local pro-inflammatory factors may play a role in the pathogenesis of atopic/allergic and autoimmune diseases, obesity, depression, and atherosclerosis. These abnormalities and the failure of the adaptive systems to resolve inflammation affect the well-being of the individual, including behavioral parameters, quality of life and sleep, as well as indices of metabolic and cardiovascular health. These hypotheses require further investigation, but the answers should provide critical insights into mechanisms underlying a variety of common human immune-related diseases.
Efavirenz Induces Depressive-Like Behaviour, Increased Stress Response and Changes in the Immune Response in Rats
Authors: O’Mahony Siobhain M. , Myint Aye-Mu , Steinbusch Harry , Leonard Brian E.
Published: September 2005

Efavirenz is a non-nucleoside reverse transcriptase inhibitor that is used in the treatment of the HIV-1 variant. Adverse central nervous system side effects such as headache, dizziness, insomnia, fatigue, severe depression and suicidal ideation are noted in patients receiving efavirenz. In this study, the effects of efavirenz on changes in behaviour and on some pro- and anti-inflammatory cytokines in Wistar rats were studied to assess whether efavirenz causes depressive symptoms via the cytokine network and, if so, whether antidepressant therapy known to attenuate the effects of pro-inflammatory cytokines could prevent these changes. The efavirenz-treated rats displayed spatial memory deficits in the Morris water maze. These rats also appeared to be more susceptible to stress than the other groups as seen by an increase in the latency to emerge in the home cage emergence test following the stress of the Morris water maze. The concentrations of pro-inflammatory cytokines interleukin-1β and tumour necrosis factor-α were also significantly higher in the efavirenz group. The antidepressant paroxetine reduced the susceptibility to stress and prevented such an increase in pro-inflammatory cytokines. It is concluded that efavirenz induces depressive-like behaviour in the rat and a susceptibility to stress, which are accompanied by an increase in pro-inflammatory cytokines. These symptoms are partially alleviated by chronic treatment with paroxetine.