bluuebunny/crossref_metadata_2025 huggingface dataset:
Assortative Pairing Based on Contact Call Similarity in Budgerigars, Melopsittacus undulatus
Authors: Moravec Marin L. , Striedter Georg F. , Burley Nancy Tyler
Published: September 2006

A trait typical of parrots, but rare in other groups of birds, is the acquisition of new learned calls (acquired by copying conspecifics) throughout an individual's lifetime. The significance of this distinctive psittacid trait is not understood. In budgerigars, females preferentially affiliate with unfamiliar males whose contact calls resemble their own during brief dyadic choice trials; also, in forced‐pair situations, contact call similarity of members of pairs increases as a result of a male tendency to imitate his mate's call type. The functions of budgerigar call imitation and preference for pre‐pairing similarity are currently unknown. Moreover, as budgerigar pair formation occurs over a span of days or weeks, it is important to determine whether birds in breeding colonies assort and proceed to breed on the basis of pre‐pairing contact call similarity, and whether high levels of call similarity are maintained after pair formation is complete. To explore these questions, we recorded contact calls of male and female budgerigars before and after they were placed into an aviary equipped for breeding. As predicted, birds paired assortatively based on pre‐pairing call similarity. Once birds had paired, their calls converged further in acoustic structure, as previous work had led us to expect. However, after eggs were laid and the males began to feed their mates, the calls of mated birds diverged, suggesting that there might be some cost to maintenance of shared calls. Male care‐giving correlated with the degree to which his pre‐pairing calls resembled those of his mate, but not with the similarity achieved through convergence. These results suggest that female budgerigars may use a male's pre‐pairing call similarity as a predictor of paternal investment. The questions of why such similarity predicts male care‐giving, and why calls converge following initial pairing activities, require further work.
Metformin‐associated lactic acidosis in patients with renal impairment solely due to drug accumulation?
Authors: Runge S. , Mayerle J. , Warnke C. , Robinson D. , Roser M. , Felix S. B. , Friesecke S.
Published: September 2006

Aim:  We suspect that the life‐threatening complication of metformin‐associated lactic acidosis, solely due to drug accumulation following renal impairment, occurs more frequently than that previously reported and is not necessarily associated with other predisposing factors for lactic acidosis.

Methods:  During a period of 13 months, at a tertiary referral centre, the incidence of lactic acidosis of any aetiology was 12.8% [67 of 524 total intensive care unit (ICU) admissions]. Metformin‐associated lactic acidosis solely as the result of drug accumulation was diagnosed in 6% of all the patients suffering from lactic acidosis (4 of 67 patients).

Results:  These patients presented with severe circulatory shock due to lactic acidosis. We could not identify any predisposing factor for lactic acidosis other than renal impairment. Intercurrent deterioration of diabetic nephropathy was suspected to be responsible for the accumulation of metformin followed by lactic acidosis, finally resulting in multiorgan failure. The diagnosis was supported by extensively elevated serum levels of metformin. Two patients died during ICU treatment.

Conclusions:  Our data indicate that the incidence of metformin‐associated lactic acidosis solely due to metformin accumulation is possible and underestimated. Symptoms of metformin‐associated lactic acidosis are unspecific and physicians should be aware that metformin, if prescribed in patients with renal impairment, can cause fatal lactic acidosis due to drug accumulation.
Size at the onset of sexual maturity in the anomuran crab, Aegla uruguayana (Aeglidae)
Authors: Viau Verónica E. , López Greco Laura S. , Bond‐Buckup Georgina , Rodríguez Enrique M.
Published: September 2006

The size at maturity was studied in the crab Aegla uruguayana from the Areco River (31°14′ S, 59°28′ W), Argentina. Size at sexual maturity was determined according to three criteria: morphometric (change in the relative growth of reproductive characters), histological (first maturation of gonads) and functional (capability to mate and carry eggs). Regarding females, morphometric maturity occurred at a carapace length (CL) of 11.50 mm, considering abdomen width as a reproductive character. Gonad maturity of females could be observed at a minimum size ranging from 15 to 17 mm CL. The smallest ovigerous female observed in the field was 15.60 mm CL, although a relevant population incidence of ovigerous females (86.6%) has just been observed at values higher than 17 mm CL. As for males, the relative growth of the left chela length changed at a value of 15.40 mm CL, while morphological changes in sexual tube occurred between CL of 14 and 16 mm. Testicular maturation occurred at a CL ranging from 17 to 19 mm. The smallest size of males having spermatozoids in their vasa deferentia was 18.70 mm CL. The results obtained indicated that, in both sexes, functional maturity occurred after morphometric maturity and at a size similar to that of gonad maturity. Comparing sexes, females acquired sexual maturity (morphometric, gonad and functional maturity) at sizes statistically smaller than those of males.
A spinose stem group brachiopod with pedicle from the Middle Cambrian Burgess Shale
Authors: Holmer Lars Erik , Caron Jean‐Bernard
Published: September 2006

A new genus and species of a Middle Cambrian stem group brachiopod, Acanthotretella spinosa n. gen. and n. sp., is described from the Burgess Shale Formation. Most of the 42 specimens studied came from the Greater Phyllopod bed (Walcott Quarry) and were collected from five bed assemblages, each representing a single obrution event. Specimens are probably preserved within their original habitat. In contrast to all brachiopods known from the Burgess Shale, the shells of the new stem group brachiopod are often deformed and do not show signs of brittle breakage, which suggests that the valves were originally either entirely organic in composition or, more likely, had just a minor mineral component. Acanthotretella spinosa differs from all the other described Cambrian brachiopods in that it is covered by long, slender and possibly partly mineralized spines that are posteriorly inclined at an oblique angle away from the anterior margin. The spines penetrate the shell and are mainly comparable with the thorn‐like organic objects that have been inferred from early siphonotretoid brachiopods. The pedicle was slender and was composed of a central coelomic region and emerged from an apical foramen at the end of an internal pedicle tube. The finding of a pedicle attached to the macrobenthic algae Dictyophycus and other epibenthos implies that A. spinosa did not have an infaunal mode of life. The visceral region and interior characters are poorly preserved.
The biology of vernix caseosa
Authors: Hoath S. B. , Pickens W. L. , Visscher M. O.
Published: September 2006

Synopsis

The biology and physical properties of the uniquely human skin cream ‘vernix caseosa’ are discussed. This material coats the foetal skin surface during the last trimester of gestation and provides multiple beneficial functions for the foetus and newborn infant. Vernix has a complex structure similar to stratum corneum but lacks lipid lamellae and is more plastic due to the absence of desmosomal constraints. In utero, vernix is made in part by foetal sebaceous glands, interacts with pulmonary surfactant, detaches into the amniotic fluid, and is swallowed by the foetus. At the time of birth, vernix has a remarkably constant water content approximating 80%. Postnatally, vernix is simultaneously a cleanser, a moisturizer, an anti‐infective, and an anti‐oxidant. Vernix facilitates acid mantle development and supports normal bacterial colonization. Its hydrated cellular structure and unusual lipid composition provide a ‘best’ solution for the needs of the foetus and newborn, not least of which is the attraction of caregivers. Vernix is an important natural biomaterial of potential interest to cosmetic scientists, and other disciplines involved in product development and therapies targeting the complex interface between the stratum corneum and a changing terrestrial environment.
Standardized Tests and Froebel's Original Kindergarten Model
Authors: Jeynes William H.
Published: September 2006

The author argues that American educators rely on standardized tests at too early an age when administered in kindergarten, particularly given the original intent of kindergarten as envisioned by its founder, Friedrich Froebel. The author examines the current use of standardized tests in kindergarten and the Froebel model, including his emphasis on moral education, play, and family involvement. This article explains the extent to which research supports the value of Froebel's model. The author asserts how increasingly, over the last four decades, American educators have departed from the Froebel kindergarten rubric supposedly, in part, to compete with Japanese students. Ironically, however, the Japanese still cherish and practice Froebel's original concept. The author contends that American educators should return to the Froebel rubric and provides a vision for doing so.
Being a Novice Teacher in Two Different Settings: Struggles, Continuities, and Discontinuities
Authors: Flores Maria Assunçao
Published: September 2006

Drawing upon empirical research, the article explores the ways in which a cohort of novice teachers learned and developed over a 2-year period. It examines the interplay of personal and contextual influences on teachers’ development over time and on the (transformation of their professional identities. A combination of methods for data collection was used. Findings suggested that novices felt overwhelmed by the amount and variety of duties that they were expected to perform at school. This, along with the lack of support and guidance, forced them into “learning while doing.” Most teachers developed according to a narrow and individual perspective, which was accompanied by a shift from a more inductive and student-centered approach to a more traditional one. However, some teachers seem to have developed in positive ways over time. Personal biographies associated with perceptions of school culture and leadership help to explain both similarities and differences among teachers. Implications of the findings for teacher education and induction are discussed.
Rounding up Unusual Suspects: Facing the Authority Hidden in the History Classroom
Authors: Bain Robert B.
Published: September 2006

Educational reform literature is filled with criticism of the omniscient tone that teachers and textbooks assume in history classrooms. Such widely acknowledged criticism often accompanies calls for more ambitious pedagogy. The focus on teachers and texts essentially ignores the ritualized and traditional deference that students afford to the authority of texts and teachers. Disturbing these rituals is essential for reform pedagogy to take root. However, we lack examples of successful classroom alternatives, namely descriptions of challenging history instruction that treats textbooks and teachers from within the discipline. This article provides such an example by considering activities that encourage students to question the omniscient tones of history text and teacher. Using my high school history classroom as a case study, I consider two questions: What might encourage students to raise disciplined suspicions of the typical sources of scholastic authority? Further, what might we learn about history instruction by trying to situate textbooks and teachers within the realm of historical inquiry—that is, making them the objects of students’ historical study? The article suggests ways to narrow the gap between reform rhetoric and pedagogical predicament when confronting the classroom authority of text and teacher.
The Effect of R&D Subsidies on Private R&D
Authors: GÖRG HOLGER , STROBL ERIC
Published: September 2006

This paper investigates the relationship between government support for R&D and R&D expenditure financed privately by firms using a comprehensive plant level data set for the manufacturing sector in the Republic of Ireland. We find that for domestic plants small grants serve to increase private R&D spending, while too large a grant may crowd out private financing of R&D. In contrast, evidence for foreign establishments suggests that grant provision causes neither additionality nor crowding out effects of private R&D financing, regardless of the size of the subsidy.
Italy is not a good place for men: narratives of places, marriage and masculinity among Malayali migrants
Authors: GALLO ESTER
Published: September 2006

Abstract Immigration from South Asia to Italy is a recent phenomenon and novel in that the pioneer migrants are often married or single women rather than men. In this article I explore the relationship between a ‘feminization of migration’ and the construction of masculine identities among Malayali migrants from Kerala, South India, who experience migration directly or indirectly through marriages with Malayali women living and working in Rome. The interest in focusing on the relation between women's pioneer role as migrants and their husbands' experiences of migration is to show how men's identity is represented through their conjugal bond with migrant women working in the domestic sector and to understand how masculinity is constructed and contested within and with reference to different places.
The transnational work of kinship and caring: Bengali–British marriages in historical perspective
Authors: GARDNER KATY
Published: September 2006

Abstract In this article, based on ongoing research carried out in Bangladesh since the mid‐1980s and field‐work in London in the late 1990s, I take a historical approach to the analysis of transnational Sylheti marriages. By showing how the form of these marriages has changed since the mid‐twentieth century, I argue that transnational migration is itself highly fluid. The role of wives in maintaining transnational links is central to the account. I focus in particular on the wives of ‘first‐generation’ migrant men who came to Britain in the 1950s and 1960s, and whose families were generally reunited in Britain by the 1980s. By describing the household and caring work of these wives both in Sylhet and London, I demonstrate that rather than being ‘dependants’ of their migrant husbands, women have been central to the success of migrant households. The rewards of transnational connectedness have, however, come at a cost — long‐term separation from loved ones. Isolation and loneliness have been hallmarks of the experiences of these earlier generations of women.
Aspiration, reunification and gender transformation in Jat Sikh marriages from India to Canada
Authors: MOONEY NICOLA
Published: September 2006

Abstract In this article I explore marriage as a strategy of family migration among a transnational community of middle‐class Jat Sikhs. Family reunification and status aspirations are examined as central concerns of the transnational movement of Jat Sikhs from India to Canada. It is argued that Jat Sikh transnationalism and gender are mutually‐constitutive: migration strategies can construct women, as well as men, as agents of marital citizenship, and in facilitating migration, transnational marriage may transform practices and notions of gender and status. The article is based on preliminary ethnographic research among Jat Sikh brides in Toronto and Vancouver, and forms part of a larger study of gender, modernity and identity in Indo‐Canadian Jat Sikh marriages.
Workplace Drug Testing and Worker Drug Use
Authors: Carpenter Christopher S.
Published: September 2006

Objective. To examine the nature and extent of the association between workplace drug testing and worker drug use.

Data Sources. Repeated cross‐sections from the 2000 to 2001 National Household Surveys on Drug Abuse (NHSDA) and the 2002 National Survey on Drug Use and Health (NSDUH).

Study Design. Multivariate logistic regression models of the likelihood of marijuana use are estimated as a function of several different workplace drug policies, including drug testing. Specific questions about penalty severity and the likelihood of detection are used to further evaluate the nature of the association.

Principal Findings. Individuals whose employers perform drug tests are significantly less likely to report past month marijuana use, even after controlling for a wide array of worker and job characteristics. However, large negative associations are also found for variables indicating whether a firm has drug education, an employee assistance program, or a simple written policy about substance use. Accounting for these other workplace characteristics reduces—but does not eliminate—the testing differential. Frequent testing and severe penalties reduce the likelihood that workers use marijuana.

Conclusions. Previous studies have interpreted the large negative correlation between workplace drug testing and employee substance use as representing a causal deterrent effect of drug testing. Our results using more comprehensive data suggest that these estimates have been slightly overstated due to omitted variables bias. The overall pattern of results remains largely consistent with the hypothesis that workplace drug testing deters worker drug use.
Assigning Ambulatory Patients and Their Physicians to Hospitals: A Method for Obtaining Population‐Based Provider Performance Measurements
Authors: Bynum Julie P. W. , Bernal‐Delgado Enrique , Gottlieb Daniel , Fisher Elliott
Published: September 2006

Objective. To develop a method for assigning Medicare enrollees and the physicians who serve them to individual hospitals with adequate validity to allow population‐based assessments of provider specific costs and quality of care.

Data Sources/Study Setting. The study populations consist of a 20 percent sample of Medicare fee‐for‐service enrollees and all physicians submitting claims for Medicare services from 1998 to 2000. Data were obtained from Medicare claims and enrollment files, Medicare's MPIER file, and from the American Hospital Association Annual Survey.

Study Design. Cross‐sectional analysis of the characteristics of hospitals, their extended medical staffs (EMSs) and the utilization patterns of their assigned Medicare enrollees.

Data Collection Methods. Medicare enrollees were assigned to their predominant ambulatory physician and then to the hospital where that physician provided inpatient services or where a plurality of that physician's patient panel had medical admissions. Each beneficiary was linked to a physician and a hospital regardless of whether the patient was hospitalized creating Ambulatory Provider Specific Cohorts (APSCs).

Principal Findings. Ninety‐six percent of eligible Medicare enrollees who had an index physician visit in 1998 were assigned to a specific provider. Two‐thirds of the medical admissions during a 2‐year period occurred at the assigned hospital and two‐thirds of evaluation and management services were billed by the assigned hospital's EMS. The empirically derived EMS for hospitals had reasonable face and discriminant validity in terms of number and type of physicians practicing at different sized and type hospitals. Estimates of risk‐adjusted costs across physician groups in year one are highly predictive of costs in a subsequent year (r=0.87, p<.0001 and weighted κ=0.65, p<.0001).

Conclusions. Medicare claims data can be used to assign virtually all Medicare enrollees to empirically defined care systems comprised of hospitals and the physicians who practice at these hospitals. Studies of patterns of practice, costs and outcomes of care experienced by these APSCs could complement other methods of monitoring provider performance.
The Effects of Health Sector Market Factors and Vulnerable Group Membership on Access to Alcohol, Drug, and Mental Health Care
Authors: Stockdale Susan E. , Tang Lingqi , Zhang Lily , Belin Thomas R. , Wells Kenneth B.
Published: September 2006

Objective. This study adapts Andersen's Behavioral Model to determine if health sector market conditions affect vulnerable subgroups' use of alcohol, drug, and mental health services (ADM) differently than the general population, focusing specifically on community‐level predisposing and enabling characteristics.

Data Sources. Wave 2 data (2000–2001) from the Health Care for Communities study, supplemented with cases from wave 1 (1997–1998), were merged with area characteristics taken from Census, Area Resource File (ARF), and other data sources.

Study Design. The study used four‐level hierarchical logistic regression to examine access to ADM care from any provider and specialty ADM access. Interactions between community‐level predisposing and enabling vulnerability characteristics with individual race/ethnicity, age, income category, and insurance type were explored.

Principal Findings. Nonwhites, the poor, uninsured, and elderly had lower likelihoods of service use, but interactions between race/ethnicity, income, age and insurance status with community‐level vulnerability factors were not statistically significant for any service use. For ADM specialty care, those with Medicare, Medicaid, private fully managed, and private partially managed insurance, the likelihood of utilization was higher in areas with higher HMO penetration. However, for those with other insurance or no insurance plan, the likelihood of utilization was lower in areas with higher HMO penetration.

Conclusions. Community‐level enabling factors explain part of the effect of disadvantaged status but, with the exception of the effect of HMO penetration on the relationship between insurance and specialty care use, do not modify any of the residual individual‐level effects of disadvantage. Interventions targeting both structural and individual levels may be necessary to address the problem of health disparities. More research with longitudinal data is necessary to sort out the causal direction of social context and ADM access outcomes, and whether policy interventions to change health sector market conditions can shift ADM treatment utilization.
Is Democracy Good for the Poor?
Authors: Ross Michael
Published: September 2006

Many scholars claim that democracy improves the welfare of the poor. This article uses data on infant and child mortality to challenge this claim. Cross‐national studies tend to exclude from their samples nondemocratic states that have performed well; this leads to the mistaken inference that nondemocracies have worse records than democracies. Once these and other flaws are corrected, democracy has little or no effect on infant and child mortality rates. Democracies spend more money on education and health than nondemocracies, but these benefits seem to accrue to middle‐ and upper‐income groups.
Institutional Inconsistency and Political Instability: Polity Duration, 1800–2000
Authors: Gates Scott , Hegre Håvard , Jones Mark P. , Strand Håvard
Published: September 2006

This article examines how political institutional structures affect political instability. It classifies polities as autocracies or democracies based on three institutional dimensions: election of the executive, constraints on executive decision‐making authority, and extent of political participation. It hypothesizes that strongly autocratic and democratic regimes will exhibit the greatest stability resulting from self‐enforcing equilibria, whereby the maintenance of a polity's institutional structure is in the interest of political elites, whether through autocratic or democratic control. Institutionally inconsistent regimes (those exhibiting a mix of institutional characteristics of both democracy and autocracy) lack these self‐enforcing characteristics and are expected to be shorter‐lived. Using a log‐logistic duration model, polity survival time ratios are estimated. Institutionally consistent polities are significantly more stable than institutionally inconsistent polities. The least stable political systems are dictatorships with high levels of political participation. The most unstable configuration for polities with an elected executive is one where the executive is highly constrained, but the electorate is very small.
Lies, Defection, and the Pattern of International Cooperation
Authors: Svolik Milan
Published: September 2006

This article characterizes how incentives to lie affect international cooperation and the design of cooperation agreements. I study the optimal structure of cooperation agreements in an environment where the costs of cooperation fluctuate over time. Cooperation is complicated by the fact that the costs of cooperation are private information and participants can benefit from lying about them. When the extent of asymmetries of information between the cooperating governments can be measured in terms of the transparency of the political process, democracies face greater contracting opportunities than authoritarian regimes. However, this article shows that even under asymmetries of information, a limited extent of cooperation can be achieved when the design of cooperation agreements recognizes incentives to lie.
Space Matters: Designing Better Electoral Systems for Emerging Democracies
Authors: Barkan Joel D. , Densham Paul J. , Rushton Gerard
Published: September 2006

Although the holding of founding and subsequent elections is essential for any transition from authoritarian to democratic rule, the comparative literature on electoral system design is limited on the experience of “Third Wave” democratizers. This is especially true with respect to the interactive effects between the choice of electoral system and the spatial, i.e., geographic, distribution of the vote—a critical factor that shapes electoral outcomes in all societies, but particularly in emerging democracies because many are plural and agrarian societies. Political elites in these countries have also rarely considered the impact of alternative electoral systems when selecting a system for their country. This article addresses these gaps in the literature and practice by presenting a computational model known as a spatial decision support system or SDSS that both explores these interactive effects and facilitates electoral design. The utility of the model is then demonstrated with data from Kenya and South Africa—two emerging democracies where issues posed by the spatial distribution of the vote have given rise to demands for redesigning or modifying the electoral system.
Electoral Competition, Globalization, and Subnational Education Spending in Mexico, 1999–2004
Authors: Hecock R. Douglas
Published: September 2006

This article examines the determinants of primary education spending among 29 Mexican states from 1999 to 2004. There is wide variation in spending despite expectations of policy convergence due to market forces associated with globalization, and in spite of the unique potential of education spending to complement economic strategies in achieving equitable growth. This study exploits significant advantages of subnational analysis in exploring political and economic variables that have been useful in explaining spending levels cross‐nationally. Consistent with these studies, this article shows that greater electoral competition leads to increased spending. In contrast to other work, however, this study finds that exposure to the global economy has distinctly mixed effects on education spending. These findings thus further highlight the positive returns to higher “quality” democracy, while underscoring the need to examine the effects of many different aspects of globalization representing a wide variety of strategies employed by governments in engaging the international economy.
A New Electorate? Comparing Preferences and Partisanship between Immigrants and Natives
Authors: Dancygier Rafaela , Saunders Elizabeth N.
Published: September 2006

As immigrants constitute a large and rising share of both the population and the electorate in many developed democracies, we examine aspects of immigrant political behavior, a vital issue that has gone largely unexplored outside of the U.S. context. We focus on Germany and Great Britain, two countries that provide good leverage to explore both within‐country and cross‐national variation in Europe. Our overall aim is to assess the impact of the immigration context. As a first step, we investigate whether immigrants and natives have systematically different attitudes on two issues that have dominated postwar European politics: social spending and redistribution. With controls in place, we observe that immigrants are no more likely to support increased social spending or redistributive measures than natives and find support for hypotheses highlighting selection effects and the impact of the immigration regime. Where we do find an opinion gap, immigrants tend to have more conservative preferences than natives. As a second step, we explore the determinants of immigrant partisan identification in Britain and find that the salience of the immigration context helps explain immigrants' partisan attachment to the Labour Party.
Seeing Difference: The Effect of Economic Disparity on Black Attitudes toward Latinos
Authors: Gay Claudine
Published: September 2006

Rapid growth in the size of the Latino population has increased the ethnic diversity of urban neighborhoods, transforming the residential experiences of many black Americans. The competition for scarce resources is considered a central force in black‐Latino relations and a source of anti‐Latino sentiment among blacks. This article examines how the level and the distribution of economic resources within diverse areas affect black attitudes toward Latinos. Drawing on a multilevel dataset of individual racial attitudes and neighborhood characteristics, the analysis reveals that the relative economic status of racial groups is an important influence on black attitudes. In environments where Latinos are economically advantaged relative to their black neighbors, blacks are more likely to harbor negative stereotypes about Latinos, to be reluctant to extend to Latinos the same policy benefits they themselves enjoy, and to view black and Latino economic and political interests as incompatible. While the results suggest that diversity without conflict is possible, they make clear that the prospects for intergroup comity depend on some resolution of blacks' economic insecurities.
The Value Premium and the CAPM
Authors: FAMA EUGENE F. , FRENCH KENNETH R.
Published: September 2006

We examine (1) how value premiums vary with firm size, (2) whether the CAPM explains value premiums, and (3) whether, in general, average returns compensate β in the way predicted by the CAPM. Loughran's (1997) evidence for a weak value premium among large firms is special to 1963 to 1995, U.S. stocks, and the book‐to‐market value‐growth indicator. Ang and Chen's (2005) evidence that the CAPM can explain U.S. value premiums is special to 1926 to 1963. The CAPM's more general problem is that variation in β unrelated to size and the value‐growth characteristic goes unrewarded throughout 1926 to 2004.
Are IPO Allocations for Sale? Evidence from Mutual Funds
Authors: REUTER JONATHAN
Published: September 2006

Combining data on brokerage commissions that mutual fund families paid for trade execution between 1996 and 1999 with data on mutual fund holdings of initial public offerings (IPOs), I document a robust, positive correlation between commissions paid to lead underwriters and reported holdings of the IPOs they underwrite. Moreover, I find that the correlation is limited to IPOs with nonnegative first‐day returns and strongest for IPOs that occur shortly before mutual funds report their holdings, when the noise introduced by flipping is smallest. Overall, the evidence suggests that business relationships with lead underwriters increase investor access to underpriced IPOs.
Automation versus Intermediation: Evidence from Treasuries Going Off the Run
Authors: BARCLAY MICHAEL J. , HENDERSHOTT TERRENCE , KOTZ KENNETH
Published: September 2006

This paper examines the choice of trading venue by dealers in U.S. Treasury securities to determine when services provided by human intermediaries are difficult to replicate in fully automated trading systems. When Treasury securities go “off the run” their trading volume drops by more than 90%. This decline in trading volume allows us to test whether intermediaries' knowledge of the market and its participants can uncover hidden liquidity and facilitate better matching of customer orders in less active markets. Consistent with this hypothesis, the market share of electronic intermediaries falls from 81% to 12% when securities go off the run.
Retail Investor Sentiment and Return Comovements
Authors: KUMAR ALOK , LEE CHARLES M.C.
Published: September 2006

Using a database of more than 1.85 million retail investor transactions over 1991–1996, we show that these trades are systematically correlated—that is, individuals buy (or sell) stocks in concert. Moreover, consistent with noise trader models, we find that systematic retail trading explains return comovements for stocks with high retail concentration (i.e., small‐cap, value, lower institutional ownership, and lower‐priced stocks), especially if these stocks are also costly to arbitrage. Macroeconomic news and analyst earnings forecast revisions do not explain these results. Collectively, our findings support a role for investor sentiment in the formation of returns.
On Identifiability in Capture–Recapture Models
Authors: Holzmann Hajo , Munk Axel , Zucchini Walter
Published: September 2006

Summary We study the issue of identifiability of mixture models in the context of capture–recapture abundance estimation for closed populations. Such models are used to take account of individual heterogeneity in capture probabilities, but their validity was recently questioned by Link (2003, Biometrics59, 1123–1130) on the basis of their nonidentifiability. We give a general criterion for identifiability of the mixing distribution, and apply it to establish identifiability within families of mixing distributions that are commonly used in this context, including finite and beta mixtures. Our analysis covers binomial and geometrically distributed outcomes. In an example we highlight the difference between the identifiability issue considered here and that in classical binomial mixture models.
Retrovirus RNA Trafficking: From Chromatin to Invasive Genomes
Authors: Swanson Chad M. , Malim Michael H.
Published: September 2006

Full‐length retroviral RNA has three well‐established functions: it constitutes the genomic RNA that is packaged into virions and is transmitted to target cells by infection, it is the messenger RNA (mRNA) template for viral Gag and Pol protein synthesis and it serves as the pre‐mRNA for the production of subgenomic spliced mRNAs that encode additional viral proteins such as Env. More recent work indicates that these full‐length RNAs also play important roles in the assembly of virus particles, not only as a structural scaffold that facilitates viral core formation but also as a potential regulator of the assembly process itself. Here, we discuss how these assorted activities may be coupled with each other, paying particular attention to the importance of RNA trafficking and subcellular localization in the cytoplasm, possible points of regulation, and the role(s) played by cellular RNA‐binding proteins.
Ternary SNARE Complexes Are Enriched in Lipid Rafts during Mast Cell Exocytosis
Authors: Puri Niti , Roche Paul A.
Published: September 2006

Lipid rafts are membrane microdomains rich in cholesterol and glycosphingolipids that have been implicated in the regulation of intracellular protein trafficking. During exocytosis, a class of proteins termed SNAREs mediate secretory granule–plasma membrane fusion. To investigate the role of lipid rafts in secretory granule exocytosis, we examined the raft association of SNARE proteins and SNARE complexes in rat basophilic leukemia (RBL) mast cells. The SNARE protein SNAP‐23 co‐localized with a lipid raft marker and was present in detergent‐insoluble lipid raft microdomains in RBL cells. By contrast, only small amounts (<20%) of the plasma membrane SNARE syntaxin 4 or the granule‐associated SNARE vesicle‐associated membrane protein (VAMP)‐2 were present in these microdomains. Despite this, essentially all syntaxin 4 and most of VAMP‐2 in these rafts were present in SNARE complexes containing SNAP‐23, while essentially none of these complexes were present in nonraft membranes. Whereas SNAP‐23 is membrane anchored by palmitoylation, the association of the transmembrane protein syntaxin 4 with lipid rafts was because of its binding to SNAP‐23. After stimulating mast cells exocytosis, the amount of syntaxin 4 and VAMP‐2 present in rafts increased twofold, and these proteins were now present in raft‐associated phospho‐SNAP‐23/syntaxin 4/VAMP‐2 complexes, revealing differential association of SNARE fusion complexes during the process of regulated exocytosis.
Systemic antibiotic therapy of acne vulgaris
Authors: Ochsendorf Falk
Published: September 2006

Background: Inflammatory, medium to severe acne vulgaris is treated with systemic antibiotics worldwide. The rationale is an effect on Propionibacterium acnes as well as the intrinsic anti‐inflammatory properties of these antibiotics. Although there are no correlations between the number of P. acnes and the severity of the disease, associations between the degree of humoral and cellular immune responses towards P. acnes and the severity of acne have been reported. Exact data on practical use of these compounds, such as differential efficacy or side effects are unavailable.A summary of currently available studies is presented.

Methods: The data of studies of systemic antibiotic therapy of acne vulgaris up to 1975, the summary of literature in English up to 1999, a systematic review of minocycline from 2002 as well as the data of randomized controlled studies published and listed in Medline thereafter were reviewed.

Results: Tetracyclines [tetracycline 1 000 mg daily, doxycycline 100 (−200) mg daily, minocycline 100 (−200) mg daily, lymecycline 300 (−600) mg] and erythromycin 1 000 mg daily are significantly more effective than placebo in the systemic treatment of inflammatory acne.The data for tetracycline are best founded. Clindamycin is similarly effective. Co‐trimoxazole and trimethoprim are likely to be effective. Clear differences between the tetracyclines or between tetracycline and erythromycin cannot be ascertained. The data for the combination with topical treatments [topical benzoyl peroxide (BPO) or retinoids] suggest synergistic effects.Therefore systemic antibiotics should not be used as monotherapy.

In case of similar efficacy, other criteria, such as pharmacokinetics (doxycycline, minocycline, lymecycline have longer half‐lives than tetracyclines), the rate of side‐effects (tetracycline: side effect‐rate ∼4 % mild side effects; erythromycin: frequent gastrointestinal complaints; minocycline: rare, but potentially severe hypersensitivity reactions; doxycycline: dose‐dependent phototoxic reactions), the resistance rate [percentage of resistant bacteria higher with erythromycin (∼ 50 %) than with tetracycline‐therapy (∼ 20 %)], and the costs of therapy have to be taken into account.

Conclusions: The systemic antibiotic therapy of widespread papulo‐pustular acne not amenable to a topical therapy is effective and well‐tolerated. In general therapy can be carried out for 3 months and should be combined with BPO to prevent resistance.
Axillary acne agminata (lupus miliaris disseminatus faciei with axillary involvement)
Authors: Hillen Uwe , Schröter Stefan , Denisjuk Natalja , Jansen Thomas , Grabbe Stephan
Published: September 2006

Acne agminata (AA) and lupus miliaris disseminatus faciei (LMDF) have been used to describe very similar clinical conditions and it is now generally accepted that they are synonymous.The cause of these disorders has not been determined. Clinically the disease presents with often agminated redbrown to yellow papules which occasionally become pustular. Microscopically, superficial granulomatous inflammation with perifollicular caseating granulomas is the hallmark. Axillary involvement with LMDF has rarely been reported; in this area AA has been the preferred term. When only the axillae are affected, it may be difficult to distinguish acne agminata from other granulomatous diseases, especially from granulomas caused by antiperspirants containing aluminumzirconium complexes. We describe a 36‐year‐old woman with axillary acne agminata.
The use of an acellular dermal regenerative tissue matrix in the treatment of lower extremity wounds: a prospective 16‐week pilot study
Authors: Brigido Stephen A
Published: September 2006

A prospective, single‐centre, randomized controlled study was performed to evaluate the effectiveness of Graftjacket, a human acellular regenerative tissue matrix as a treatment option for chronic non healing lower extremity wounds. Twenty‐eight diabetic patients with full‐thickness wounds that had been present for at least 6 weeks were treated with sharp debridement and randomized to a single application of Graftjacket tissue matrix plus mineral oil‐soaked fluff compression dressing or to a control treatment of wound gel with gauze dressings. All patients were seen weekly. By week 16, 12 of 14 patients treated with Graftjacket tissue matrix demonstrated complete wound closure compared with 4 of 14 patients in the control group. Patients treated with Graftjacket tissue matrix showed a statistically significant higher percentage of wound healing with respect to wound area, and clinically significant differences in wound depth and wound volume. This comparison is not performed to demonstrate that the application of the Grafjacket is more effective than sharp debridement. This study is done to help assign a role to the use of Graftjacket matrix in lower extremity wound care.
Topical application of the tumour necrosis factor‐α antibody infliximab improves healing of chronic wounds
Authors: Streit Markus , Beleznay Zsuzsanna , Braathen Lasse R
Published: September 2006

The role of tumour necrosis factor‐alpha (TNF‐α) in wound healing is not clear. Elevated levels of TNF‐α have been observed in fluids from chronic wounds and have been shown to decrease over time during the healing process. Therapeutic antibodies such as infliximab can inhibit TNF‐α activity. In this case series, we applied infliximab topically to eight patients with chronic ulcers of more than 4‐month durations. The ulcers had multifactorial aetiology, with chronic venous insufficiency being the most prominent factor. All the ulcers had failed to respond to any previous conventional treatment. Infliximab was applied repeatedly to ulcers either as a 10 mg/ml solution and covered with an adhesive sheet or as a gel formulation (0·45, 1, or 4·5 mg/g) under a hydrofiber dressing/adhesive sheet. Improvement was assessed by measuring the percentage of change in the ulcer surface area. Seven of the eight patients (12 of 14 ulcers) responded to treatment with infliximab. After 4 weeks of treatment, surface area was reduced by more than 50% in 6 of the 14 treated ulcers. Within 8 weeks, five ulcers completely healed, while another four were reduced by more than 75% in size. Chronic, therapy‐resistant leg ulcers responded well to repeated topical administration of a solution or a gel containing the TNF‐α antibody, infliximab. Randomised controlled studies should be conducted to further evaluate the effect of topical infliximab on chronic wound healing.
Surgical treatment of hidradenitis suppurativa: case series and review of the literature
Authors: Ather Shahzad , Chan David SY , Leaper David J , Harding Keith G
Published: September 2006

The chronic and relapsing nature of hidradenitis suppurativa leads to physical and psychological damage. The absence of a proven cure further worsens the scenario. Patient 1 was a 28‐year‐old woman with a 10‐year history of abscesses and non healing sinuses with foul‐smelling discharge from her axilla, submammary and groin areas. This led to an episode of self‐harm due to severe depression. After failed medical therapy, she was referred for surgery with wide excision of the skin and healing by secondary intention. Her wounds were managed by our specialist wound clinic with the use of topical and systemic antibiotics and thus remained free from symptoms. Patient 2 was a 32‐year‐old woman with a similar history for 15 years. Patient 3 was a 41‐year‐old man with a 20‐year history of discharging sinuses and abscesses. All the patients had endured a long period of medical treatment and subsequently required surgery for a long‐term relief of symptoms. This has undoubtedly led to psychological symptoms and a decrease in quality of life.
Validation of a diabetic foot surgery classification
Authors: Armstrong David G , Lavery Lawrence A , Frykberg Robert G , Wu Stephanie C , Boulton Andrew JM
Published: September 2006

The purpose of this project was to evaluate associations of increasing diabetic foot surgery stage with postoperative outcome. This project, designed as a retrospective cohort model, was conducted at three large, urban referral‐based diabetic foot clinics. The investigators abstracted medical records from 180 patients with diabetes, 76·1% male, aged 57·8 ± 11·2 years, falling equally into four classes of a previously reported diabetic foot surgery classification system. These classes included class 1 (elective), class 2 (prophylactic), class 3 (curative) and class 4 (emergency). There was a significant trend towards increasing risk of ulceration/reulceration (χ2trend= 17·8,P= 0·0001), peri‐postoperative infection (χ2trend= 96·9,P= 0·0001), all‐level amputation (χ2trend= 41·7P= 0·001) and major amputation (χ2trend= 8·6,P= 0·003), with increasing class of foot surgery. The results of this study suggest that a non vascular foot surgery classification system including variables such as the presence or absence of neuropathy, an open wound and acute infection may be predictive of peri‐ and postoperative complications. This may assist the surgeon in better identifying risk when determining a rationale for and type of surgery in persons with diabetes.
Healing of large midline wounds in infants: unlike in adults, does conservative approach give better results? Two case reports and review of the literature
Authors: Suliman M Taifour
Published: September 2006

The case of two infants with large midline wounds, one with an omphalocele and the other with a lumbosacral wound secondary to ruptured meningocele, is reported wherein the advantages of leaving such wounds in infants to heal spontaneously over surgical intervention are shown. In this report, the cases are discussed and the literature is reviewed. It is concluded that the midline wounds in infants yield better results if left to heal spontaneously.