bluuebunny/crossref_metadata_2025 huggingface dataset:
Vertical Networks, Integration, and Connectivity
Authors: Doğan Pinar
Published: April 2009

This paper studies competition in a network industry with a stylized two layered network structure, and examines: (i) price and connectivity incentives of the upstream networks, and (ii) incentives for vertical integration between an upstream network provider and a downstream firm. The main result of this paper is that vertical integration occurs only if the initial installed‐base difference between the upstream networks is sufficiently small, and in that case, industry is configured with two vertically integrated networks, which yields highest incentives to invest in quality of interconnection. When the installed‐base difference is sufficiently large, there is no integration in the industry, and neither of the firms have an incentive to invest in quality of interconnection. An industry configuration in which only the large network integrates and excludes (or raises cost of) its downstream rival does not appear as an equilibrium outcome: in the presence of a large asymmetry between the networks, when quality of interconnection is a strategic variable, the large network can exercise a substantial market power without vertical integration. Therefore, a vertically separated industry structure does not necessarily yield procompetitive outcomes.
Market‐Share Contracts with Asymmetric Information
Authors: Majumdar Adrian , Shaffer Greg
Published: April 2009

In this paper, a dominant firm and competitive fringe supply substitute goods to a retailer who has private information about demand. We show that it is profitable for the dominant firm to condition payment on how much the retailer buys from the fringe (market‐share contracts). The dominant firm thereby creates countervailing incentives for the retailer and, in some cases, is able to obtain the full‐information outcome (unlike in standard screening models, where the agent earns an information rent in the high‐demand state and output is distorted in the low‐demand state). Our results have implications for fidelity rebates, all‐units discounts, and competition policy. Although some crowding out of the fringe may occur when demand is low, we show that market‐share contracts need not be harmful for welfare.
Barriers to Entry of a Vertically Integrated Health Insurer: An Analysis of Welfare and Entry Costs
Authors: Ho Katherine
Published: April 2009

I investigate the reasons why market expansion attempts by vertically integrated health insurers have largely failed. I use an econometric model of consumer demand for hospitals and insurers to simulate entry of an integrated plan into 28 new markets. The results indicate that entry would increase social surplus by over $34 billion per year. I then investigate several potential barriers to entry. Three are particularly important. Integrated plans cannot attract enough enrollees to support their provider networks unless they exceed competitor quality levels and convince consumers of this benefit. Regulatory restrictions on plans building new facilities may also be important.
The Role of Upstream‐Downstream Competition on Bundling Decisions: Should Regulators Force Firms to Unbundle?
Authors: Rennhoff Adam D. , Serfes Konstantinos
Published: April 2009

We develop an upstream–downstream model to analyze downstream firms' incentives to bundle. In our framework, the upstream firms are content providers (such as television stations) and the downstream firms are system operators (such as cable/satellite operators). We show that an a la carte regulation (i.e., a regulation that forces downstream firms to unbundle) leads to higher consumer surplus, if the unregulated equilibrium exhibits pure bundling (PB). Hence, our model predicts that in the television industry, which is mainly characterized by PB, an a la carte regulation will be beneficial for the consumers. If, on the other hand, the unregulated equilibrium is characterized by mixed bundling, then an a la carte regulation will increase consumer welfare provided that demand for multiple purchases is strong.
Yardstick Competition and Quality
Authors: Tangerås Thomas P.
Published: April 2009

This paper explores the consequences for quality of introducing yardstick competition in duopoly when a verifiable quality indicator is available. Yardstick competition can be implemented by a menu of transfers that are linear in the cost differential between the two firms and in quality. Cost‐ and quality incentives are stronger in larger firms when improvements are highly valued by consumers and firms can significantly influence quality. Expenditures on quality improvement can increase or decrease following the introduction of yardstick competition. The crucial factor is the likelihood ratio of productivity between the two firms, not productivity differences.
Stored red blood cell supernatant facilitates thrombin generation
Authors: Sweeney Joseph , Kouttab Nicola , Kurtis Jonathan
Published: April 2009

BACKGROUND: Observational studies have reported that patients transfused with red blood cells (RBCs) have a worse clinical outcome than untransfused patients and that storage age of RBCs at the time of transfusion may be an independent predictor of this adverse clinical outcome.

STUDY DESIGN AND METHODS: Eight RBC concentrates in additive solution were studied over an 8‐week storage period. The RBC supernatant was ultracentrifuged to concentrate microvesicles (RCMVs). RCMVs were studied by flow cytometry to identify phosphatidylserine (PS)‐expressing RCMVs and in a thromboelastograph (TEG) using a modified assay to detect a thrombin facilitation effect.

RESULTS: For all products, the percentage of RCMVs that exhibited PS expression on Day 1 was 50 ± 13%, which increased with storage, and on Day 31 was 90 ± 4%. After 31 days, four of the eight products showed a thrombin facilitation effect as evidenced by a shortening of the TEG reaction (R) time of 1.3 ± 1.1 minutes, which persisted to Day 41. Data are the mean ± 1 SD. This TEG R shortening effect was neutralized by annexin V. No such effect was observed on, or before, Day 21.

CONCLUSIONS: Some stored RBCs release RCMVs, which express PS and are capable of facilitating thrombin generation in vitro. This provides a possible mechanism by which stored RBCs could promote adverse thrombotic or inflammatory effects.
Egg‐laying tactic inPhyllomorpha laciniatain the presence of parasitoids
Authors: Carrasco David , Kaitala Arja
Published: April 2009

Female insects are expected to choose oviposition sites that have the best conditions for offspring development and survival. Natural enemies, such as predators and parasitoids, may have a strong influence on the selection of oviposition substrates by phytophagous insects. The golden egg bug,Phyllomorpha laciniata(Villers) (Heteroptera: Coreidae) has an unusual reproductive strategy. Females mainly use conspecifics, both males and other females, as egg‐laying substrates, but occasionally they oviposit on plants as well. Survival of the eggs is higher when eggs are carried by conspecifics than when they are laid on plants, due to predation and parasitism. We investigated egg‐laying behavior in the forced presence of the egg parasitoidGryon bolivari(Giard) (Hymenoptera: Scelionidae). Specifically, we studied whether females provide egg protection by avoiding oviposition under the risk of egg parasitization. We expected a lower oviposition rate under parasitoid presence, and the eggs, if any, to be placed preferably on conspecifics and not on plants, thus ensuring higher survival of the progeny. The results show thatP. laciniata’s egg‐laying rate was lower when they were enclosed with parasitoids than when parasitoids were absent, especially when plants were the only substrate to oviposit on. Moreover, females showed strong preference for laying eggs on conspecifics rather than on plants. Egg‐laying inP. laciniataappears to be not only influenced by the availability of conspecifics, but also by the presence of egg parasitoids. This indicates that females may be able to detectG. bolivariand avoid oviposition when parasitoids are present. We discuss the possibility of conspecifics as enemy‐free space.
Spatio‐temporal analysis of an invasive plant pathogen (Phytophthora ramorum) in England and Wales
Authors: Xu Xiangming , Harwood Thomas D. , Pautasso Marco , Jeger Mike J.
Published: April 2009

Phytophthora ramorum is a damaging invasive plant pathogen and was first discovered in the UK in 2002. Spatial point analyses were applied to the occurrence of this disease in England and Wales during the period of 2003–2006 in order to assess its spatio‐temporal spread. Out of the 4301 garden centres and nurseries (GCN) surveyed, there were 164, 105, 123 and 41 sites with P. ramorum in 2003, 2004, 2005 and 2006, respectively. Spatial analysis of the observed point patterns of GCN outbreaks suggested that these sites were significantly clumped within a radius of ca 60 km in 2003, but not in later years. Further analyses were conducted to determine the relationship of GCN outbreak sites over two consecutive years and thus to infer possible disease spread over time. This analysis suggested that disease spread among GCN sites was most likely to have occurred within a distance of 60 km for 2003–2004, but not for the later years. There were 35, 63, 81 and 58 sites with P. ramorum in the semi‐natural environment (SNE). Analyses were carried out to assess whether infected GCN sites could act as an inoculum source of infected SNE plants or vice versa. In all years, there was a significant spatial closeness among GCN and SNE outbreak sites within a distance of 1 km. But a significant relationship over a longer distance (within 60 km) was only observed between cases in 2003 and 2004. These analyses suggest that statutory actions taken so far appear to have reduced the extent of long‐distance spread of P. ramorum among garden centres and nurseries, but not the disease spread at a shorter distance between GCN and SNE sites.
The Calcium Channel Mucolipin‐3 is a Novel Regulator of Trafficking Along the Endosomal Pathway
Authors: Martina Jose A. , Lelouvier Benjamin , Puertollano Rosa
Published: April 2009

The varitint‐waddler phenotype in mice is caused by gain‐of‐function mutations in mucolipin‐3 (MCOLN3), a member of the mucolipin family of ion channels. These mice are characterized by defects in pigmentation, hearing loss and vestibular defects, suggesting that MCOLN3 might play a role in melanosome trafficking and hair cell maturation. Recent evidence has shown that MCOLN3 is a Ca2+–permeable channel and its activity is regulated by pH. Here we show that MCOLN3 primarily localizes to early and late endosomes in human epithelial cells. This distribution at the less acidic portions of the endocytic pathway is consistent with the reported inactivation of the channel by low pH. Furthermore, overexpression of MCOLN3 causes dramatic alterations in the endosomal pathway, including enlargement of Hrs‐positive endosomes, delayed degradation of epidermal growth factor (EGF) and EGF receptor (EGFR) and defective autophagosome maturation, whereas depletion of endogenous MCOLN3 enhances EGFR degradation. Finally, we found that endosomal pH is higher in cells overexpressing MCOLN3 and propose a model in which Ca2+ release from endosomes mediated by MCOLN3 might be important for efficient endosomal acidification. Therefore, MCOLN3 is a novel Ca2+ channel that plays a crucial role in the regulation of cargo trafficking along the endosomal pathway.
Erv26p‐Dependent Export of Alkaline Phosphatase from the ER Requires Lumenal Domain Recognition
Authors: Dancourt Julia , Barlowe Charles
Published: April 2009

Active sorting at the endoplasmic reticulum (ER) drives efficient export of fully folded secretory proteins into coat protein complex II (COPII) vesicles, whereas ER‐resident and misfolded proteins are retained and/or degraded. A number of secretory proteins depend upon polytopic cargo receptors for linkage to the COPII coat and ER export. However, the mechanism by which cargo receptors recognize transport‐competent cargo is poorly understood. Here we examine the sorting determinants required for export of yeast alkaline phosphatase (ALP) by its cargo receptor Erv26p. Analyses of ALP chimeras and mutants indicated that Erv26p recognizes sorting information in the lumenal domain of ALP. This lumenal domain sorting signal must be positioned near the inner leaflet of the ER membrane for Erv26p‐dependent export. Moreover, only assembled ALP dimers were efficiently recognized by Erv26p while an ALP mutant blocked in dimer assembly failed to exit the ER and was subjected to ER‐associated degradation. These results further refine sorting information for ER export of ALP and show that recognition of folded cargo by export receptors contributes to strict ER quality control.
Importins and Beyond: Non‐Conventional Nuclear Transport Mechanisms
Authors: Wagstaff Kylie M. , Jans David A.
Published: April 2009

The movement of proteins between the cytoplasm and the nucleus conventionally involves the recognition of nuclear targeting signals by members of the importin (Imp) superfamily of nuclear transporters, followed by translocation through the nuclear envelope‐embedded nuclear pore complexes (NPCs). It is becoming increasingly apparent, however, that distinct alternative pathways for nuclear transport exist and are relatively abundant. This review examines several of these novel pathways, including facilitation of Imp‐dependent transport by microtubule motors, and Imp‐independent pathways involving either other transport molecules such as the calcium‐binding protein calmodulin or through direct binding to the components of the NPC. The existence of these pathways and the fact that many proteins appear to possess separate Imp‐dependent and ‐independent nuclear import mechanisms ensure that the cell can function under conditions in which Imp‐dependent transport is inhibited and/or modulate the efficiency of Imp‐dependent transport itself, according to the need.
Spontaneous recovery of an intensively used grassland after cessation of fertilizing
Authors: Královec Josef , Pocová Lenka , Jonášová Magda , Macek Petr , Prach Karel
Published: April 2009

Questions: (1) Does a fertilized grassland recover in terms of species composition and species richness after stopping the treatment? (2) Which species contributed most to the changes? (3) Is it realistic to rely upon spontaneous recovery in this and similar cases?

Location: A large grassland, located in the western part of the Czech Republic in central Europe, latitude 49° 59′, longitude 12° 45′, altitude 750 m a.s.l.

Methods: Experimental plots of 2.5 m × 6.0 m were established in the central part of the grassland in 1968 using a randomized block design with the following variants: unfertilized controls, 80, 160, 240 and 320 kg ha−1 of nitrogen, in four or eight (320 kg) replicates. The fertilization regime was stopped in 1989. Phytosociological relevés of 2 m × 4 m in size were made in 1990, 1994, 1996, 1997, 1999, 2003 and 2006. The data were processed by multivariate ordination methods (DCA, CCA). Differences in the number of species per plot were tested by repeated measures anova and Tukey's HSD test.

Results: All plots, including controls, exhibited a distinct trajectory through time, reflecting the rates of fertilizer used and generally changing in the same direction. Both time and nutrients significantly influenced the vegetation pattern. Treatments differed significantly in species richness, especially at the beginning of the observation. Differences in later years were less pronounced, thus a convergence between the treatments was evident.

Conclusions: During the 16 years after fertilization ceased, the number of species substantially increased not only in the fertilized plots but also in the controls. Species typical of semi‐natural grasslands predominantly contributed to the increase. Spontaneous recovery after cessation of fertilizing was relatively efficient, but the fertilized plots were small in size and thus rather easily colonized from outside. For interpretation and extrapolation of results from small experimental plots, it is necessary to consider changes in the broader surroundings.
CLO‐PLA: the database of clonal and bud bank traits of Central European flora§
Authors: Klimešová Jitka , De Bello Francesco
Published: April 2009

Abstract: Clonal growth of plants is mainly a result of the vegetative growth of organs hidden beneath the soil surface and producing potentially independent vegetative offspring. Clonal traits are difficult to measure due to inaccessibility of the space they inhabit and their morphological diversity. This causes great difficulties with descriptions, standardization of measurements across plant growth forms and, probably, a lack of appropriate questions that should be answered using them. The freely available CLO‐PLA database (http://clopla.butbn.cas.cz/) can help to assess the roles of vegetative means of regeneration and spread in plant communities under the effect of various biotic and abiotic filters. It can serve as a source of reference on persistence traits of European temperate flora and, eventually, as a guide for trait sampling in other regions of the world.
Assessing the impact of plant invasions on soil seed bank communities: use of univariate and multivariate statistical approaches
Authors: Gioria Margherita , Osborne Bruce
Published: April 2009

Questions: Are soil seed banks affected by invasions of alien plants? How can we rigorously assess alterations in seed bank communities associated with invasive species and account for the high spatial variability of seed bank data? How do multivariate approaches compare with more traditional approaches based on analysis of variance?

Location: Three riparian sites, Ireland.

Methods: A protocol based on a combination of multivariate techniques was used to characterize soil seed bank communities associated with the herbaceous invasive species Heracleum mantegazzianum in May and October. Permutational multivariate analysis of variance (PERMANOVA) was used to test the effects of the factors “invasion”, “site”, “plot” and “depth” on the soil seed bank, while multivariate analysis of dispersion (PERMDISP) provided a measure of the variability of seed bank data at different spatial scales. Similarity percentages analysis (SIMPER) was used to identify the species that contributed most to the differences between invaded and uninvaded communities. A comparison between the results of PERMANOVA and ANOVA analyses was also made.

Results: The composition of seed bank communities invaded by H. mantegazzianum differed significantly from that of uninvaded seed banks. Invaded seed banks were less diverse and had reduced abundance, and were dominated by only a few species, such as Urtica dioica and Juncus effusus. Such patterns were recorded at each of three depth categories, indicating that invasive plants can affect both the transient and the more persistent component of the soil seed bank. Seed bank variability was significantly higher within uninvaded areas, supporting the notion that invasions tend to lead to more homogeneous communities.

Conclusion: The analytical protocol used in this study was effective in quantifying the effect of plant invasions, at different spatial scales, providing a statistically robust analysis of alterations in soil seed bank communities. Compared to ANOVA, this protocol provided more biological information and was more appropriate for analysis of the data. This approach is therefore recommended in soil seed bank and invasion ecological studies.
Species‐specific stomatal response of trees to drought – a link to vegetation dynamics?
Authors: Zweifel R. , Rigling A. , Dobbertin M.
Published: April 2009

Question: Is stomatal regulation specific for climate and tree species, and does it reveal species‐specific responses to drought? Is there a link to vegetation dynamics?

Location: Dry inner alpine valley, Switzerland

Methods: Stomatal aperture (θE) of Pinus sylvestris, Quercus pubescens, Juniperus communis and Picea abies were continuously estimated by the ratio of measured branch sap flow rates to potential transpiration rates (adapted Penman‐Monteith single leaf approach) at 10‐min intervals over four seasons.

Results: θE proved to be specific for climate and species and revealed distinctly different drought responses: Pinus stomata close disproportionately more than neighbouring species under dry conditions, but has a higher θE than the other species when weather was relatively wet and cool. Quercus keeps stomata more open under drought stress but has a lower θE under humid conditions. Juniperus was most drought‐tolerant, whereas Picea stomata close almost completely during summer.

Conclusions: The distinct microclimatic preferences of the four tree species in terms of θE strongly suggest that climate (change) is altering tree physiological performances and thus species‐specific competitiveness. Picea and Pinus currently live at the physiological limit of their ability to withstand increasing temperature and drought intensities at the sites investigated, whereas Quercus and Juniperus perform distinctly better. This corresponds, at least partially, with regional vegetation dynamics: Pinus has strongly declined, whereas Quercus has significantly increased in abundance in the past 30 years. We conclude that θE provides an indication of a species' ability to cope with current and predicted climate.
Impact of competition on plant performances along a flooding gradient: a multi‐species experiment
Authors: Jung Vincent , Mony Cendrine , Hoffmann Lucien , Muller Serge
Published: April 2009

Question:1. How do the competitive response and the importance of competition vary between species and along a flooding gradient? 2. How does the role of competition in constraining species distribution limits along the gradient vary between lower and upper limits?

Location:A 1‐ha meadow within the Alzette floodplain in Luxembourg.

Methods:Competitive response and importance of competition were assessed on seven meadow species differing in their tolerance to flooding. Species were cultured in monocultures and in mixtures, in three water treatments reflecting the wet, the middle and the dry end of a natural flooding gradient. We developed two models based on a multiple regression in order to express each component of competition as a function of the neighbour biomass.

Results:Five species showed variations in their competitive response across water treatments; however, these species achieved either their highest or their worst competitive response in their optimal water treatment (i.e. the treatment in which the species had the highest biomass in monoculture). Competition was more important for the flood‐tolerant species in the dry treatment than for the flood‐intolerant species in the wet treatment.

Conclusions:1. Variations in species competitive responses along flooding gradients may be the result of either an amplified effect between competition and hydrological stresses, or a hierarchical effect of stress over competition. 2. The role of competition is more important in constraining the upper distribution limits of the flood‐tolerant species than the lower limits of the flood‐intolerant species along flooding gradients.
Using Evidence to Determine Diagnostic Test Efficacy
Authors: Replogle William H. , Johnson William D. , Hoover Kim Welch
Published: April 2009

Background: Various measures are used to summarize a diagnostic test's efficacy in deciding on the disease status of patients.

Measures: Sensitivity and specificity indicate the probability of a positive or negative test result, given that the patient either has or does not have, respectively, a specified disease, and are the most commonly reported measures of test efficacy. Predictive values indicate the probability of a disease, given the patient's diagnostic test result is positive or negative, and are more useful in clinical decision making. Predictive values are useful only if the prevalence of disease in the study sample is representative of the prevalence in the population of diagnostic interest. A likelihood ratio is the sensitivity of a test divided by one minus the specificity and is used as a multiplier of the pretest odds of a disease to obtain the posttest odds. The resulting posttest odds can be converted to a posttest probability of disease that is identical to the predictive value of the test.

Implications for Practice: An estimate of the posttest probability of disease that is more relevant for an individual patient can be obtained by adjusting the pretest estimate, taking into account patient characteristics and clinical experience. Using the Herren and colleagues’ work, diagnostic test efficacy measures are presented to assist practitioners in determining which tests may be accurate in “ruling in” or “ruling out” disease.
Evidence‐Based Practice: Iranian Nurses’ Perceptions
Authors: Adib‐Hajbaghery Mohsen
Published: April 2009

Background: During the past 2 decades, evidence‐based practice has increasingly been proven as a means of standard and higher‐quality health care. Nurses who base their practices on scientific evidence bring their clients and organization better and more cost‐effective nursing care. However, little is known about Iranian nurses' perceptions of evidence‐based practice.

Aims: The present study was conducted to evaluate Iranian nurses' perceptions of evidence‐based practice.

Methods: A qualitative study was conducted on 21 participants from different groups of nurses at Kashan University of Medical Sciences. Semi‐structured interviews were used to gather data. Content analysis was used to analyze the data according to the Cheevakumjorn's method.

Findings: Two main categories, the concept of “evidence‐based nursing” and “nature and the source of evidence,” emerged from the data. The participants used the term “standard care” as a synonym for evidence‐based practice. According to the participants, the nurses implement evidence‐based practice care for clients based on their professional knowledge and the patient's needs. The participants believed “caring evidence” includes five different types of knowledge: “knowledge of patient,”“knowledge of the environment,”“learned (academic) knowledge,”“practice‐based knowledge,” and “research‐based knowledge.” However, participants stated that, currently, the nursing practice is not based on scientific evidence.

Conclusions: Nurses have a positive attitude concerning the use of scientific evidence to guide practice, but this evidence has little application in their current nursing practice.

Implications: Nurses need support from both the organizational management and the educational system to help them apply evidence in practice.
Multisite protein phosphorylation – from molecular mechanisms to kinetic models
Authors: Salazar Carlos , Höfer Thomas
Published: April 2009

Multisite phosphorylation is an important mechanism for fine‐tuned regulation of protein function. Mathematical models developed over recent years have contributed to elucidation of the functional consequences of a variety of molecular mechanisms involved in processing of the phosphorylation sites. Here we review the results of such models, together with salient experimental findings on multisite protein phosphorylation. We discuss how molecular mechanisms that can be distinguished with respect to the order and processivity of phosphorylation, as well as other factors, regulate changes in the sensitivity and kinetics of the response, the synchronization of molecular events, signalling specificity, and other functional implications.
The IκBα gene is a peroxisome proliferator‐activated receptor cardiac target gene
Authors: Buroker Norman E. , Barboza Julia , Huang Jie‐Yu
Published: April 2009

The purpose of this study was to provide a better understanding of the regulatory role of the nuclear steroid receptor on the nuclear factor of kappa light polypeptide gene enhancer in B cells (NFκB) in mouse heart. NFκB regulates many nuclear genes and has been associated with many human cardiac diseases. NFκB’s protein regulator gene, nuclear factor of kappa light polypeptide gene enhancer in B cells inhibitor alpha gene (IκBα), was found in this study to be regulated by peroxisome proliferator‐activated receptors (PPARs). PPARs, retinoid X receptors (RXRs) and thyroid hormone receptors (THRs) are members of the nuclear receptor superfamily, which consists of a large number of transcription factors whose activities are regulated by their cognate ligands. These steroid hormone receptors are important regulators of gene expression and differentiation in the heart. These receptors form homo‐(RXR, THR) and hetero‐(PPAR–RXR, RXR–THR) dimers that bind DNA at various response elements (PPAR, RXR and THR) in the promoter regions of target genes. The PPAR/RXR response elements in the promoter of IκBα are described in this article. A known PPAR activator (Wy14643) and dimethylsulfoxide (vehicle) were introduced into control (FVB) and δ337T thyroid hormone receptor (TRβ) transgenic mice. The δ337T TRβ transgenic mouse has a resistance to the thyroid hormone (RTH) phenotype. Affymetrix 430_2 chip gene expression was examined for four study groups (control, control with Wy14643, δ337T TRβ and δ337T TRβ with Wy14643), consisting of seven mice each. IκBα mRNA expression in the Wy14643 control and in transgenic mice was upregulated significantly in microarray (P < 0.05) and quantitative RT‐PCR (P < 0.01) analyses. The increase in mRNA level was also accompanied by an increase in IκBα protein in cells, as measured by Western blot analysis. Duplex oligo‐DNAs containing the putative PPAR/RXR motif (AGGTCA/TCCAGT) from the IκBα promoter were used in gel shift assays to verify the binding of PPAR and RXR to their response elements. pGL4.0 [Luc] constructs of the IκBα promoter, with and without the PPAR/RXR motifs, were co‐transfected with mouse PPAR α, β and γ1 into HepG2 cells and used in luciferase assays to verify gene activation. In conclusion, our study revealed that PPAR regulates the mouse cardiac IκBα gene in both control and transgenic mouse heart. The implications of this finding are discussed in relation to possible changes in cardiac function.
The Association Between Internet Use and Depressive Symptoms Among South Korean Adolescents
Authors: Park Sunhee
Published: April 2009

PURPOSE.  This study explores the cross‐sectional relationship between Internet use and depressive symptoms in South Korean adolescents.

DESIGN AND METHODS.  Existing data, the three‐wave Korean Youth Panel Survey, were analyzed. The sample was a cohort representing the population of second‐year students at Korean middle schools in 2003 (N = 3,449). Multivariate logistic regression was used.

RESULTS.  A one‐unit increase in Internet use was positively associated with a 20.7% increase in risk for depressive symptoms.

PRACTICE IMPLICATIONS.  It may be worthwhile for nursing professionals to inquire about Internet use as part of a measure of screening for depressive symptoms in teens.
Psychosocial Experiences of Parents of a Child With Imperforate Anus
Authors: Nisell Margret , Öjmyr‐Joelsson Maria , Frenckner Björn , Rydelius Per‐Anders , Christensson Kyllike
Published: April 2009

PURPOSE.  This study aims to examine the psychosocial experiences of parents of children with imperforate anus (IA) and to describe their potential positive experiences.

DESIGN AND METHODS.  Parents of IA children and a comparison group answered a questionnaire, which was analyzed quantitatively and with manifest content analysis.

RESULTS.  Social relationships and respect for the child's will were more affected among IA mothers. Positive experiences were revealed in relation to the child, the parent, and the family.

PRACTICE IMPLICATIONS.  Support to parents in caring for a child with IA should be individualized and occasionally undertaken through collaboration with experts from child and adolescent psychiatry.
On the reported death of the MACHO era
Authors: Quinn D. P. , Wilkinson M. I. , Irwin M. J. , Marshall J. , Koch A. , Belokurov V.
Published: April 2009

We present radial velocity measurements of four wide halo binary candidates from the sample in Chaname & Gould (CG04) which, to date, is the only sample containing a large number of such candidates. The four candidates that we have observed have projected separations >0.1 pc, and include the two widest binaries from the sample, with separations of 0.45 and 1.1 pc. We confirm that three of the four CG04 candidates are genuine, including the one with the largest separation. The fourth candidate, however, is spurious at the 5σ level. In the light of these measurements, we re-examine the implications for MAssive Compact Halo Object (MACHO) models of the Galactic halo. Our analysis casts doubt on what MACHO constraints can be drawn from the existing sample of wide halo binaries.
PHL 1092 as a transient extreme X-ray weak quasar
Authors: Miniutti G. , Fabian A. C. , Brandt W. N. , Gallo L. C. , Boller Th.
Published: April 2009

We report a dramatic variability event in the X-ray history of the narrow-line quasar PHL 1092 (z= 0.396). Our latest 2008 XMM-Newton observation reveals a flux drop of ∼200 with respect to the previous observation performed about 4.5 yr earlier, and a drop of ∼135 with respect to its historical flux. Despite the huge X-ray variation, the UV flux remains constant producing a very significant steepening of the optical to X-ray slope αox from −1.56 to −2.44, making PHL 1092 one of the most extreme X-ray weak quasars. The similarity in the soft X-ray spectral shape between the present and previous observations, together with the persistent UV flux and the lack of any dramatic change in the optical spectrum, suggests that an absorption event is not likely to be the origin of the observed variation. If absorption is ruled out, the sudden X-ray weakness of PHL 1092 must be produced by a transient significant weakening or disruption of the X-ray emitting corona.
Management of quadriceps contracture in a dog using a static flexion apparatus and physiotherapy
Authors: Moores A. P. , Sutton A.
Published: April 2009

A four‐month‐old golden retriever developed quadriceps contracture following management of a comminuted femoral fracture with an intramedullary pin and cerclage wire. Management involved surgical release of the quadriceps, rigid stabilisation of the fracture, use of a static stifle flexion apparatus and postoperative physiotherapy. The dog returned to full activity with normal stifle function.
Clinical, histopathological and genetic data of ichthyosis in the golden retriever: a prospective study
Authors: Guaguere E. , Bensignor E. , Küry S. , Degorce‐Rubiales F. , Muller A. , Herbin L. , Fontaine J. , André C.
Published: April 2009

Objectives: We described epidemiological, clinical, histopathological and ultrastructural features of ichthyosis in the golden retriever breed in a prospective study. We also investigated the mode of transmission of this disease.

Materialsand Methods: We examined 150 golden retrievers, 73 of which were affected by ichthyosis (35 males and 38 females). We carried out detailed clinical and histopathological examinations for 40 affected dogs. Transmission electron microscopy was performed for two of them. We used pedigree analysis with the Cyrillic software to determine the mode of transmission.

Results: Dermatological signs included a mild to moderate or severe generalised scaling with initially small to large whitish scales and progressively blackish scales. The ventral glabrous skin was hyperpigmented and rough, similar to sandpaper. Histopathological features were characterised by moderate to severe laminated or compact orthokeratotic epidermal hyperkeratosis without significant involvement of the stratum granulosum. Ultrastructural findings revealed laminated or compact keratin layers and numerous persistent corneodesmosomes within the stratum corneum. Analysis of the pedigree suggested an autosomal recessive inheritance.

Conclusion: The histopathological and ultrastructural characteristics strongly suggest that golden retriever ichthyosis is a retention ichthyosis, caused by absence of corneodesmosomal degradation, transmitted through an autosomal recessive mode.
Variation in position of the medial fabella in West Highland white terriers and other dogs
Authors: Störk C. K. , Petite A. F. , Norrie R. A. , Polton G. A. , Rayward R. M
Published: April 2009

Objectives: To investigate whether West Highland white terriers exhibit significant variation in the position of the medial fabella compared to both small and large breed dogs.

Methods: Criteria for the normal location of the medial fabella on a caudocranial radiograph were established. A retrospective analysis was undertaken of a consecutive series of bilateral caudocranial stifle joint radiographs from 70 West Highland white terriers, 100 small and 100 large control dogs by three reviewers. Medial fabellar location, cruciate ligament disease and medial patellar luxation were examined within and between groups.

Results: Abnormal medial fabellar location was identified in 70 per cent, 9 per cent and 0 per cent of West Highland white terriers, small dogs and large dogs, respectively. In the vast majority of the affected dogs, the fabella was found in a mediodistal location. Presence of concurrent cranial cruciate ligament disease or medial patellar luxation and body weight was excluded as confounding factors.

Clinical Significance: West Highland white terriers appear predisposed to, and have a high prevalence of, an abnormal mediodistal location of the medial fabella. The authors suggest this is an incidental finding and should not be confused with true pathological fabellar displacement.
An Atlas of Interpretative Radiographic Anatomy of the Dog and Cat
Authors: Holloway Andrew
Published: April 2009

An Atlas of Interpretative Radiographic Anatomy of the Dog and Cat
 Arlene Coulson with Noreen Lewis Published by Blackwell Publishing Ltd, 2008, 2nd Edition, hardback, 651 pages, Price £115.00, ISBN‐13: 9781405138994
Counting on codes: An examination of transnational codes as a regulatory governance mechanism for nanotechnologies
Authors: Bowman Diana M. , Hodge Graeme A.
Published: April 2009

This article examines the rise of nanotechnology‐specific codes of conduct (nano‐codes) as a private governance mechanism to manage potential risks and promote the technology. It examines their effectiveness as well as their legitimacy as regulatory instruments in the public domain. The study first maps the rise of voluntary nano‐codes and the roles played by different actors. Focusing on five specific nano‐codes, the article then discusses their adequacy in terms of scientific uncertainty, gaps in existing regulatory regimes, and broader societal concerns. It concludes that these voluntary nano‐codes have weaknesses including a lack of explicit standards on which to base independent monitoring, as well as no sanctions for poor compliance. At the same time it also highlights the potential power of these governance mechanisms under conditions of uncertainty and co‐regulation with government. It is likely that nano‐codes will become the “first cut” of a new governance regime for nanotechnologies.
A new species of Haborophocoena, an Early Pliocene phocoenid cetacean from Hokkaido, Japan
Authors: Ichishima Hiroto , Kimura Masaichi
Published: April 2009

Abstract

A new species of phocoenid cetacean Haborophocoena, collected from the Early Pliocene Embetsu Formation, in the close vicinity to the site where the holotype of the type species of the genus Haborophocoena was retrieved, improves our knowledge of the anatomy of this cetacean. The new species, represented by a skull, lacking distal half of the rostrum, ear bones, and teeth, is significantly smaller than, but morphologically similar to, the type species Haborophocoena toyoshimaiIchishima and Kimura 2005. This new record of Haborophocoena confirms the veracity of the genus Haborophocoena as a biological entity, contributes to understanding the interspecific variation, and suggests that the genus diversified in the northwestern Pacific of early Pliocene time. The adult‐like degree of ossification in this small skull precludes it from being a juvenile of Haborophocoena toyoshimai. Autapomorphies of Haborophocoena minutus include narrow premaxilla on the dorsal surface of the rostrum, the anterior position of the premaxillary foramen, and a distinct ridge dividing a fossa on the lateral face of the base of the zygomatic process into the dorsal and the ventral halves, the zygomatic process rectangular in lateral profile, and its small size, which is the most compelling feature, making it a distinct species.
Abundance and site fidelity of Indo‐Pacific Humpback dolphins in the Great Sandy Strait, Queensland, Australia
Authors: Cagnazzi Daniele De Biasi , Harrison Peter L. , Ross Graham J. B. , Lynch Peter
Published: April 2009

Abstract

This study examined the population of Indo‐Pacific humpback dolphins, Sousa chinensis, inhabiting the Great Sandy Strait Marine Park, Queensland, Australia. A total of 106 dolphins were identified during 228 boat‐based surveys, completed between April 2004 and April 2007. Based on the distribution of resighted individuals and the pattern of associations, it was established that this population consists of two largely geographically distinct communities, referred to as the Northern Community (NC) and the Southern Community (SC). The only recorded interaction between the two groups was a single pod composed of one member of the NC and 11 dolphins from the SC. Abundance was estimated for the entire population and by geographical area using open population models. Estimates for the Great Sandy Strait indicate that about 150 dolphins (NGSS= 148.4, SE = 8.3, 95% CI: 132.5–165.2) used this area during the study. The NC and SC total population sizes was estimated to be 76 (NNGSS= 75.80, SE = 3.88, 95% CI = 71–86) and 75 (NSGSS= 74.98, SE = 4.43, 95% CI: 66–83), respectively. Analysis of residence patterns indicates that a majority of the identified dolphins are long‐term residents.
Conversion of a Missouri River Dam and Reservoir to a Sustainable System: Sediment Management1
Authors: Howard Coker E. , Hotchkiss Rollin H. , Johnson Dennis A.
Published: April 2009

Abstract:  A present and future challenge for water resources engineers is to extend the useful life of our dams and reservoirs. Ongoing reservoir sedimentation in impoundments must be addressed; sedimentation in many reservoirs already limits project benefits and effective project life. Sustainability requires that incoming sediment be moved downstream past the impounding dam. We use Lewis and Clark Lake, the most downstream of the six Missouri River main stem reservoirs, to demonstrate how a reservoir in advanced stages of its project life could be converted to a sustainable system with local benefits exceeding costs by a factor of 1.5. Full consideration of benefits would further enhance project justification. The proposed strategy involves four phases that will take about 50 years to complete. Cost estimates for this potential project range from the quantitative to the plausible, but it is clear that the results justify a full engineering, environmental, and economic study of this model project. If implemented, the project will create scientific knowledge and develop technologies useful for achieving sustainability at many other reservoirs in the Mississippi River basin and beyond.
Characterization of microsatellite loci isolated from the wasp, Microstigmus nigrophthalmus (Hymenoptera)
Authors: LUCAS ERIC R. , HORSBURGH GAVIN J. , DAWSON DEBORAH A. , FIELD JEREMY
Published: April 2009

Fifty‐two microsatellite loci were characterized in 22–31 unrelated females of the wasp (Microstigmus nigrophthalmus) collected from the Mata do Paraiso, Viçosa, M.G., Brazil. Fifty‐one of these loci were developed from a microsatellite‐enriched genomic library derived from M. nigrophthalmus and one was derived from the wasp, Ormyrus nitidulus. The genus Microstigmus represents an independent origin of social behaviour in the Hymenoptera and is thus of great potential in the study of social evolution.
Clinical phenotype of posterior polymorphous corneal dystrophy in a family with a novel ZEB1 mutation
Authors: Nguyen Dan Q. , Hosseini Mohsen , Billingsley Gail , Héon Elise , Churchill Amanda J.
Published: April 2009

Acta Ophthalmol. 2010: 88: 695–699

Purpose:  To describe the clinical phenotype in a family with posterior polymorphous corneal dystrophy (PPCD) and a novel mutation in the ZEB1 gene.

Methods:  Clinical examination, anterior segment photography, specular microscopy and electrophysiological investigations were performed and quantified. Genomic DNA extracted from peripheral blood was sequenced for ZEB1 exons. Cosegregation of identified mutation with the disease status in the family was confirmed using polymerase chain reaction and restriction fragment length polymorphism.

Results:  Ocular examination was performed on five family members from two generations. Three had anomalies of the corneal endothelium that were consistent with PPCD. Endothelial cell counts ranged from 2306 to 2987 mm2 (ref. 2000–4000 cells/mm2). No evidence of glaucoma or retinal abnormalities was observed. Extraocular abnormalities such as inguinal herniation, hydrocoele and possible bony or connective tissue anomalies were part of the disease spectrum in this family. Mutation analysis revealed a novel change in exon 5 of ZEB1 (c.672delA) that cosegregated with the affected disease status.

Conclusion:  The detailed clinical features of PPCD associated with a novel ZEB1 mutation are supportive of the previously proposed range of phenotype parameters. Further phenotype–genotype correlations may provide insights into the clinical variability and pathological processes affecting the corneal endothelium, Descemet’s membrane, retinal photoreceptor function and extraocular tissues of some patients.
Granulocytic sarcoma of the maxillary sinus. A case report
Authors: Jo Jeong‐Hyeon , Chi Hyun‐Sook , Cho Kyung‐Ja
Published: April 2009

The present paper reports a rare case of granulocytic sarcoma (GS) with plasmacytoid features occurring in the maxillary sinus of a 63‐year‐old man. The diagnosis of GS has always been difficult, and diagnosis in the present case was made more difficult by the tumor's manifestation as longstanding maxillary sinusitis, the late development of leukemia, unusual location of the tumor, and the plasmacytoid features of the tumor cells. The potential for any lesion of any organ to be GS should be considered in a patient with hematologic abnormalities.
Hyperplasia of mesonephric remnant, epididymal type: A case report
Authors: Lee Jeong Hyeon , Kim Hyunchul , Kim Chul Hwan , Ro Jae Y.
Published: April 2009

Mesonephric rests or mesonephric remnants are vestiges of embryonic structures called mesonephric (wolffian) ducts. It usually can be seen in the lateral wall of the cervix uteri. In males, the mesonephric remnants are seen in epididymis and efferent ductules. Prostate is one of the rare locations, on which the mesonephric remnants can be found. Hyperplasia of mesonephric remnants of prostate is rare but important because sometimes it is difficult to differentiate from adenocarcinoma. The lesion is important in the differential diagnosis from the high grade prostatic intraepithelial neoplasia. Here, we report an additional case of mesonephric hyperplasia, epididymal type, in a 66‐year‐old man. Microscopically, it showed tubular structures lined by columnar cells with pseudostratified elongated hyperchromatic nuclei. The cells showed negative reaction on high molecular weight cytokeratin and prostate‐specific antigen immunostain.