bluuebunny/crossref_metadata_2025 huggingface dataset:
The Intraday Price of Money: Evidence from the e‐MID Interbank Market
Authors: BAGLIONI ANGELO , MONTICINI ANDREA
Published: September 2008

We provide empirical evidence, based on tick‐by‐tick data for the e‐MID euro area interbank market covering 2003 and 2004, that the overnight interest rate shows a clear downward pattern throughout the operating day. Thus, a positive hourly interest rate (half basis point) implicitly emerges from the intraday term structure of the overnight rate. Such a pattern was not detected in the mid‐1990s: we explain this evolution as an outcome of the recent trend toward real‐time settlement. The estimated intraday interest rate is lower than in the United States: this is due to the different cost of central bank daylight credit.
Methods for Assessing Uncertainty in Fundamental Assumptions and Associated Models for Cancer Risk Assessment
Authors: Small Mitchell J.
Published: September 2008

The distributional approach for uncertainty analysis in cancer risk assessment is reviewed and extended. The method considers a combination of bioassay study results, targeted experiments, and expert judgment regarding biological mechanisms to predict a probability distribution for uncertain cancer risks. Probabilities are assigned to alternative model components, including the determination of human carcinogenicity, mode of action, the dosimetry measure for exposure, the mathematical form of the dose‐response relationship, the experimental data set(s) used to fit the relationship, and the formula used for interspecies extrapolation. Alternative software platforms for implementing the method are considered, including Bayesian belief networks (BBNs) that facilitate assignment of prior probabilities, specification of relationships among model components, and identification of all output nodes on the probability tree. The method is demonstrated using the application of Evans, Sielken, and co‐workers for predicting cancer risk from formaldehyde inhalation exposure. Uncertainty distributions are derived for maximum likelihood estimate (MLE) and 95th percentile upper confidence limit (UCL) unit cancer risk estimates, and the effects of resolving selected model uncertainties on these distributions are demonstrated, considering both perfect and partial information for these model components. A method for synthesizing the results of multiple mechanistic studies is introduced, considering the assessed sensitivities and selectivities of the studies for their targeted effects. A highly simplified example is presented illustrating assessment of genotoxicity based on studies of DNA damage response caused by naphthalene and its metabolites. The approach can provide a formal mechanism for synthesizing multiple sources of information using a transparent and replicable weight‐of‐evidence procedure.
Subsea Release of Oil from a Riser: An Ecological Risk Assessment
Authors: Nazir Muddassir , Khan Faisal , Amyotte Paul , Sadiq Rehan
Published: September 2008

This study illustrates a newly developed methodology, as a part of the U.S. EPA ecological risk assessment (ERA) framework, to predict exposure concentrations in a marine environment due to underwater release of oil and gas. It combines the hydrodynamics of underwater blowout, weathering algorithms, and multimedia fate and transport to measure the exposure concentration. Naphthalene and methane are used as surrogate compounds for oil and gas, respectively. Uncertainties are accounted for in multimedia input parameters in the analysis. The 95th percentile of the exposure concentration (EC95%) is taken as the representative exposure concentration for the risk estimation. A bootstrapping method is utilized to characterize EC95% and associated uncertainty. The toxicity data of 19 species available in the literature are used to calculate the 5th percentile of the predicted no observed effect concentration (PNEC5%) by employing the bootstrapping method. The risk is characterized by transforming the risk quotient (RQ), which is the ratio of EC95% to PNEC5%, into a cumulative risk distribution. This article describes a probabilistic basis for the ERA, which is essential from risk management and decision‐making viewpoints. Two case studies of underwater oil and gas mixture release, and oil release with no gaseous mixture are used to show the systematic implementation of the methodology, elements of ERA, and the probabilistic method in assessing and characterizing the risk.
Gender Identity and Homophobia: The Impact on Adolescent Males Studying French   THIS ARTICLE HAS BEEN RETRACTED
Authors: KISSAU SCOTT , WIERZALIS EDWARD
Published: September 2008

Foreign and second language (L2) educators in English‐speaking countries are concerned that male students are losing interest in studying French. A large‐scale study was conducted to investigate gender differences in L2 motivation and participation among Grade 9 core French students in Canada. A mixed methodology was employed to investigate gender differences in a variety of motivational factors among Grade 9 French as a second language (FSL) students. Approximately 500 students in Grade 9 FSL completed a questionnaire. The significant findings were then explored in interviews with students and teachers. The root of several differences in motivation and participation lied in societal perceptions of what is considered gender‐appropriate male behavior. Although the study involves students studying FSL in Canada, its implications extend to learners of French in other English‐speaking countries.
Spatio‐temporal population sampling of a fire ant parasitoid
Authors: Henne Donald C. , Hilbun William S. , Johnson Seth J.
Published: September 2008

The spatial and temporal population structure of Pseudacteon tricuspis Borgmeier (Diptera: Phoridae), an introduced parasitoid of the invasive red imported fire ant, Solenopsis invicta Buren (Hymenoptera: Formicidae), was investigated at three locations in Louisiana, USA, during the fall of 2005. Georeferenced disturbed fire ant mounds that attracted adult P. tricuspis were analyzed using Spatial Analysis by Distance IndicEs to model the population structure of this parasitoid on a local spatial scale, and relate spatial abundance to host colony social form and infection with the fire ant pathogen, Thelohania solenopsae Knell, Allen and Hazard (Microsporidia: Thelohaniidae). Spatial associations between P. tricuspis counts and host S. invicta colonies infected with T. solenopsae were not detected. Overall, spatio‐temporal count patterns of P. tricuspis were largely random. However, high P. tricuspis counts were significantly associated with areas of polygyne host colonies. Occasional aggregations of P. tricuspis populations into discrete spatial patches and gaps were also found. The implications of this study are that population surveys of P. tricuspis should be conducted in several areas at a location to account for local patchiness in fly populations and/or varying densities and social form of host ant colonies.
Strategies and challenges for eliciting immunity against avian influenza virus in birds
Authors: Swayne David E. , Kapczynski Darrell
Published: September 2008

Summary: Vaccines and vaccination have emerged during the past two decades as essential tools in avian influenza (AI) control for poultry, because they increase resistance to infection, prevent illness and death, reduce virus replication and shed from respiratory and alimentary tracts, and reduce virus transmission to birds and mammals, including humans. Such protection in birds is primarily mediated by homosubtypic humoral immunity against the hemagglutinin protein, but cell‐mediated and innate immunity contribute to protection in some bird species. The immune response to the neuraminidase protein can contribute to protection, but immunity to the viral internal proteins is generally not protective. Although, some preliminary studies with M2e protein in chickens suggest partial protection may be achievable. Historically, the H5 subtype AI vaccines have demonstrated broad homosubtypic protection, primarily against H5 high‐pathogenicity (HP) AI viruses isolated in the early stages of outbreaks. However, as H5 viruses have become endemic and outbreaks prolonged, some drift variants with resistance to earlier H5 AI vaccines have emerged in Central America, China, Egypt, and Indonesia. How widespread such drift variants are will remain unknown until more detailed genetic and antigenic analyses are conducted on field isolates. Future vaccines will utilize biotechnology to produce new AI vaccine seed strains using HA genes more closely matching circulating field viruses. In addition, newer technologies for AI vaccines will improve vaccine coverage by using mass application technologies for example by drinking water, by spray, or via injection in ovo or at the hatchery.
Inhibition of interferon induction and signaling by paramyxoviruses
Authors: Fontana Judith M. , Bankamp Bettina , Rota Paul A.
Published: September 2008

Summary: The family Paramyxoviridae comprises a diverse group of viruses that includes several important human and veterinary pathogens. Members of this family have a non‐segmented, single‐stranded, negative sense RNA genome, a conserved gene order, and a similar replication strategy. Paramyxoviruses are divided into two subfamilies, Paramyxovirinae and Pneumovirinae, which comprise five genera and two genera, respectively. Viruses in each genus have developed strategies to circumvent the interferon (IFN) response by using a diverse array of proteins that are encoded within the phosphoprotein genes of the Paramyxovirinae or non‐structural genes of the Pneumovirinae. This review focuses on the specific roles that these viral proteins play in the inhibition of IFN signaling and, to a lesser extent, on the mechanisms by which these proteins inhibit the induction pathways of IFN. An improved understanding of the interactions between viral proteins and the host innate immune response is critical to achieving a thorough comprehension of the pathogenesis of this important group of viruses. Hopefully this knowledge will support the development of more targeted vaccines and therapeutics to better prevent and control viral infection.
Host responses to alphavirus infection
Authors: Ryman Kate D. , Klimstra William B.
Published: September 2008

Summary: Members of the Alphavirus genus are classified into New World and Old World groups based upon their disease characteristics and primary areas of endemicity. The two groups exhibit noteworthy differences in pathogenesis during human infection, with Old World viruses primarily causing febrile and arthritogenic diseases and the New World viruses causing encephalitis. In this review, we summarize the major factors contributing to disease manifestations observed in murine models of alphavirus infection. We concentrate upon differences between particular viruses as they relate to interaction with myeloid lineage cells (particularly dendritic cells and macrophages), both in terms of virus replication efficiency and host cell responses to infection. In addition, we discuss the effects of mutations acquired during cell culture‐adaptation of alphaviruses upon our understanding of important factors in pathogenesis. Finally, we focus on the role of host innate immune responses, in particular the type I interferon (IFN‐α/β) system, in determining the permissivity of myeloid and other cell types. Recent contributions to the current understanding of identities and mechanisms of action of IFN‐α/β‐induced antiviral effectors in vitro and in vivo are also discussed.
Immune evasion during foot‐and‐mouth disease virus infection of swine
Authors: Golde William T. , Nfon Charles K. , Toka Felix N.
Published: September 2008

Summary: The interface between successful pathogens and their hosts is often a tenuous balance. In acute viral infections, this balance involves induction and inhibition of innate responses. Foot‐and‐mouth disease virus (FMDV) is considered one of the most contagious viruses known and is characterized by rapid induction of clinical disease in cloven hoofed animals exposed to infection. Viral shedding is extensive before the equally rapid resolution of acute disease. This positive strand RNA virus is an extremely successful pathogen, due in part to the ability to interrupt the innate immune response. Previous reviews have described the inhibition of cellular innate responses in the infected cell both in vitro and in vivo. Here, we present a review of virus inhibition of cells that are a source of antiviral function in swine. Particularly in the case of dendritic cells and natural killer cells, the virus has evolved mechanisms to interrupt the normal function of these important mediators of innate function, even though these cells are not infected by the virus. Understanding how this virus subverts the innate response will provide valuable information for the development of rapidly acting biotherapeutics to use in response to an outbreak of FMDV.
Induction and termination of inflammatory signaling in group B streptococcal sepsis
Authors: Wennekamp Julia , Henneke Philipp
Published: September 2008

Summary: Group B streptococcus (GBS) is part of the normal genital and gastrointestinal flora in healthy humans. However, GBS is a major cause of sepsis and meningitis in newborn infants in the Western world and an important pathogen in many developing countries. The dissection of the host response to GBS may increase the general understanding of innate immunity in sepsis, because newborn infants lack a sufficient adaptive response. Inflammatory signal induction in macrophages by GBS seems largely preserved in newborn infants, as shown both in vitro and in vivo. The engagement of Toll‐like receptor 2 (TLR2) by lipoproteins and a myeloid differentiation factor 88 (MyD88)‐dependent pathway induced by GBS cell wall are both important in this context. TLR2 activation of microglia by GBS induces neuronal damage, which might account for the high morbidity of GBS meningitis. At the same time, TLR2 mediates activation‐induced cell death (AICD), a process involved in the containment of inflammation. In newborn infants, AICD and anti‐bacterial polymorphonuclear leukocyte activity appears to be compromised. Accordingly, neonatal aberrations in the pathogen‐specific negative control of inflammatory signaling are likely to contribute to excessive inflammation and neurological sequelae in GBS sepsis and meningitis.
Immune defense against pneumonic plague
Authors: Smiley Stephen T.
Published: September 2008

Summary: Yersinia pestis is one of the world's most virulent human pathogens. Inhalation of this Gram‐negative bacterium causes pneumonic plague, a rapidly progressing and usually fatal disease. Extensively antibiotic‐resistant strains of Y. pestis exist and have significant potential for exploitation as agents of terrorism and biowarfare. Subunit vaccines comprised of the Y. pestis F1 and LcrV proteins are well‐tolerated and immunogenic in humans but cannot be tested for efficacy, because pneumonic plague outbreaks are uncommon and intentional infection of humans is unethical. In animal models, F1/LcrV‐based vaccines protect mice and cynomolgus macaques but have failed, thus far, to adequately protect African green monkeys. We lack an explanation for this inconsistent efficacy. We also lack reliable correlate assays for protective immunity. These deficiencies are hampering efforts to improve vaccine efficacy. Here, I review the immunology of pneumonic plague, focusing on evidence that humoral and cellular defense mechanisms collaborate to defend against pulmonary Y. pestis infection.
T cells and immunopathogenesis of experimental African trypanosomiasis
Authors: Tabel Henry , Wei Guojian , Shi Meiqing
Published: September 2008

Summary: African trypanosomes are pathogens for humans and livestock. They are single‐cell, extra‐cellular parasites that cause persistent infections of the blood and induce profound immunosuppression. Here, we review recent work on experimental African trypanosomiasis, especially infections with Trypanosoma congolense, in mice with regard to mechanisms of immunosuppression and immunopathology. The center of the immunopathology is the T‐cell‐independent production of antibodies to the variant surface glycoprotein (VSG) of trypanosomes, the anti‐VSG antibody‐mediated phagocytosis of trypanosomes by macrophages, and the subsequent profound dysregulation of the macrophage system. Depending on the genetics of the host and the parasite load, the malfunction of the macrophage system is enhanced by interferon‐γ produced by parasite‐specific, major histocompatibility complex class II‐restricted, matrix‐adherent CD4+ T cells or downregulated by interleuin‐10 produced by parasite‐specific, CD4+CD25high Forkhead box protein 3+ regulatory T cells. There is a physiological conflict of the two relevant cytokines interleukin‐10 and interferon‐γ in regulating the immunopathology versus regulating the induction and effect of protective immune responses. On the basis of very recent work in our laboratory, we propose a hypothetical model suggesting a cross‐regulation of natural killer T cells and CD4+CD25high Forkhead box protein 3+ regulatory T cells in experimental infections with T. congolense.
The structural immunology of antibody protection against West Nile virus
Authors: Diamond Michael S. , Pierson Theodore C. , Fremont Daved H.
Published: September 2008

Summary: Recent investigations of the interaction between the West Nile virus (WNV) envelope protein (E) and monoclonal antibodies (mAbs) have elucidated fundamental insights into the molecular mechanisms of neutralization. Structural studies have defined an epitope on the lateral ridge of domain III (DIII‐lr) of the WNV E protein that is recognized by antibodies with the strongest neutralizing activity in vitro and in vivo. Antibodies that bind this epitope are highly potent because they efficiently block at a post‐entry step of viral infection with relatively low virion occupancy requirements. In this review, we discuss the structural, molecular, and immunologic basis for antibody‐mediated protection against WNV, and its implications for novel therapeutic or vaccine strategies.
Emerging and reemerging diseases: a historical perspective
Authors: Snowden Frank M.
Published: September 2008

Summary:Between mid‐century and 1992, there was a consensus that the battle against infectious diseases had been won, and the Surgeon General announced that it was time to close the book. Experience with human immunodeficiency virus/acquired immunodeficiency syndrome, the return of cholera to the Americas in 1991, the plague outbreak in India in 1994, and the emergence of Ebola in Zaire in 1995 created awareness of a new vulnerability to epidemics due to population growth, unplanned urbanization, antimicrobial resistance, poverty, societal change, and rapid mass movement of people. The increasing virulence of dengue fever with dengue hemorrhagic fever and dengue shock syndrome disproved the theory of the evolution toward commensalism, and the discovery of the microbial origins of peptic ulcer demonstrated the reach of infectious diseases. The Institute of Medicine coined the term ‘emerging and reemerging diseases’ to explain that the world had entered an era in which the vulnerability to epidemics in the United States and globally was greater than ever. The United States and the World Health Organization took devised rapid response systems to monitor and contain disease outbreaks and to develop new weapons against microbes. These mechanisms were tested by severe acute respiratory syndrome in 2003, and a series of practical and conceptual blind spots in preparedness were revealed.
Understanding the contribution of cellular immunity to dengue disease pathogenesis
Authors: Mathew Anuja , Rothman Alan L.
Published: September 2008

Summary: Dengue viruses (DENV) are the mosquito‐borne viruses of greatest global public health importance. DENV circulate as four serotypes with significant immunologic cross‐reactivity that does not provide protection from secondary infection with heterologous serotypes. The strong association of severe dengue illness, dengue hemorrhagic fever (DHF), with heterologous secondary infection and high cytokine levels has led to a prevailing view that DHF is immunologically mediated. In vitro studies of DENV‐specific T lymphocytes, clinical studies of acute DENV infection, and immunologic studies in mouse models have provided evidence that in heterologous secondary DENV infection, there is preferential activation of memory T lymphocytes with lower avidity for the infecting virus (‘original antigenic sin’) resulting in altered T‐cell functional responses. In the setting of host genetic predisposition and high level viremia, with resulting high antigenic burden, we postulate that a skewed T‐cell cytokine response leads to plasma leakage in DHF. A better understanding of the immune responses associated with increased or decreased risk for DHF will be of immense value for the clinical studies of candidate multivalent DENV vaccines anticipated to take place in the next several years.
Early cellular responses to Salmonella infection: dendritic cells, monocytes, and more
Authors: Tam Miguel A. , Rydström Anna , Sundquist Malin , Wick Mary Jo
Published: September 2008

Summary: Dendritic cells (DCs), monocytes, macrophages, and neutrophils are myeloid‐derived phagocytes critical to controlling bacterial infections, and these cells have complementary functions to ensure host survival. Recent data have shed light on the dynamics and function of myeloid cells at the early stage of infection. In particular, murine infection models with Salmonella enterica serovar Typhimurium have been useful for understanding the host response required to develop immunity to systemic salmonellosis. This review summarizes the early cellular responses in the intestinal lymphoid tissues to Salmonella and discusses Peyer's patch‐dependent and ‐independent penetration of bacteria through the intestinal epithelium. Once Salmonella accesses host tissue, phagocytes respond by recruitment, redistribution, and activation in intestinal tissues. Recruited monocytes are specialized in controlling bacterial replication by producing anti‐microbial molecules but are poor antigen‐presenting cells. In contrast, DCs undergo maturation by direct (bacteria‐mediated) and indirect (cytokine‐mediated) pathways in vivo to optimize their antigen presentation capacity, and directly matured DCs have unique mechanisms to ensure T‐cell stimulation. Toll‐like receptor signaling is critical to DC maturation and myeloid cell recruitment during Salmonella infection, and the role of myeloid differentiation factor 88 (MyD88)‐dependent and MyD88‐independent pathways as well as proinflammatory cytokines and type 1 interferons in these processes are discussed.
Norovirus pathogenesis: mechanisms of persistence and immune evasion in human populations
Authors: Donaldson Eric F. , Lindesmith Lisa C. , Lobue Anna D. , Baric Ralph S.
Published: September 2008

Summary: Noroviruses are important human pathogens known to cause epidemic outbreaks of severe gastroenteritis in communities, military barracks, cruise ships, hospitals, and assisted living communities, resulting in over 267 000 000 annual infections worldwide. Diversity within the norovirus genus allows this virus to persist in human populations, although a single genocluster, the GII.4 noroviruses, currently accounts for ∼80% of all infections. Noroviruses bind to the polymorphic histoblood group antigens (HBGAs), which act as the putative cellular receptor, and strains from different genoclusters bind various HBGAs. Human challenge studies using viruses from different genoclusters have demonstrated that norovirus immunity is complicated and probably confounded by pre‐existing exposure histories and variable immune responses. Evidence for both short‐term and long‐term immunity has been demonstrated, but the molecular mechanisms mediating differential immune responses in the face of infection remain unclear. Studies with virus‐like particles from the GII.4 genocluster demonstrated that variation in and around the receptor‐binding domain results in differential HBGA binding and altered antigenicity. These observations suggest that the norovirus capsid evolves to evade the memory immune response while retaining its ability to bind any of several HBGAs. In this review, we discuss how evolution within the capsid drives receptor switching and allows escape from herd immunity.
The bacterial superantigen and superantigen‐like proteins
Authors: Fraser John D. , Proft Thomas
Published: September 2008

Summary: The bacterial superantigens are protein toxins that bind to major histocompatibility complex class II and T‐cell receptor to stimulate large numbers of T cells. The majority are produced by the Gram‐positive organisms Staphylococcus aureus and Streptococcus pyogenes and are the causative agents in toxic shock syndrome, an acute disease caused by the sudden and massive release of T‐cell cytokines into the blood stream. The structure and function of the superantigens has revealed a common architecture that is also shared by another group of staphylococcal virulence factors called the superantigen‐like proteins (SSL). Together, this family of structurally related molecules highlights how a common pathogenic organism has employed a simple but adaptable protein to generate an armamentarium of potent defense molecules designed to target of the innate and adaptive immune response.
Pathogenesis of emerging avian influenza viruses in mammals and the host innate immune response
Authors: Maines Taronna R. , Szretter Kristy J. , Perrone Lucy , Belser Jessica A. , Bright Rick A. , Zeng Hui , Tumpey Terrence M. , Katz Jacqueline M.
Published: September 2008

Summary:Influenza A viruses of avian origin represent an emerging threat to human health as the progenitors of the next influenza pandemic. In recent years, highly pathogenic avian influenza H5N1 viruses have caused unprecedented epizootics on three continents and rare but highly fatal disease among humans exposed to diseased birds. Avian viruses of the H7 and H9 subtypes have also infected humans but generally resulted in far milder disease, yet they too should be considered as possible pandemic threats. Influenza virus infection elicits a complex network of host immune responses that, in uncomplicated influenza, results in effective control of the virus and the development of long‐term memory responses. However, fatal avian H5N1 virus infection in both humans and experimental mammalian models is characterized by a high viral load in the respiratory tract, peripheral leukopenia and lymphopenia, a massive infiltration of macrophages into the lung, and dysregulation of cytokine and chemokine responses. This review focuses on avian influenza viruses as a pandemic threat, their induction of host innate immune responses in mammalian species, and the contribution of these responses to the disease process.
Monkeypox virus and insights into its immunomodulatory proteins
Authors: Weaver Jessica R. , Isaacs Stuart N.
Published: September 2008

Summary: Monkeypox is a disease that is endemic in Central and Western Africa. However, in 2003, there was an outbreak in the United States, representing the first documented monkeypox cases in the Western hemisphere. Although monkeypox virus is less fatal and not as transmissible as variola virus, the causative agent of smallpox, there is concern that monkeypox virus could become a more efficient human pathogen. The reason for this may lie in the virus' genetic makeup, ecological changes, changes in host behavior, and the fact that with the eradication of variola virus, routine smallpox vaccination is no longer carried out. In this review, we focus on the viral proteins that are predicted to modulate the host immune response and compare the genome of monkeypox virus with the genomes of variola virus and the vaccinia virus, the orthopoxvirus that represented the smallpox vaccine. There are differences found in several of these immune‐modulating genes including genes that express proteins that affect cytokines such as interleukin‐1, tumor necrosis factor, and interferon. There are also differences in genes that code for virulence factors and host range proteins. Genetic differences likely also explain the differences in virulence between two strains of monkeypox virus found in two different regions of Africa. In the current setting of limited smallpox vaccination and little orthopoxvirus immunity in parts of the world, monkeypox could become a more efficient human pathogen under the right circumstances.
Hantavirus‐induced immunity in rodent reservoirs and humans
Authors: Schönrich Günther , Rang Andreas , Lütteke Nina , Raftery Martin J. , Charbonnel Nathalie , Ulrich Rainer G.
Published: September 2008

Summary:Hantaviruses are predominantly rodent‐borne pathogens, although recently novel shrew‐associated hantaviruses were found. Within natural reservoir hosts, hantairuses do not cause obvious pathogenetic effects; transmission to humans, however, can lead to hemorrhagic fever with renal syndrome or hantavirus cardiopulmonary syndrome, depending on the virus species involved. This review is focussed on the recent knowledge on hantavirus‐induced immune responses in rodent reservoirs and humans and their impact on susceptibility, transmission, and outcome of hantavirus infections. In addition, this review incorporates a discussion on the potential role of direct cell‐virus interactions in the pathogenesis of hantavirus infections in humans. Finally, questions for further research efforts on the immune responses in potential hantavirus reservoir hosts and humans are summarized.
The relationship between personal breastfeeding experience and the breastfeeding attitudes, knowledge, confidence and effectiveness of Australian GP registrars
Authors: Brodribb Wendy , Fallon Anthony , Jackson Claire , Hegney Desley
Published: September 2008

In conjunction with other health professionals, doctors believe they play an important role in promoting breastfeeding to women. Although many have positive breastfeeding attitudes, significant knowledge deficits often limit their capacity to effectively encourage, support and assist breastfeeding women and their infants. Personal breastfeeding experience (of self or partner) may be the main source of breastfeeding knowledge and skill development and is related to improved knowledge, more positive attitudes and greater confidence. This paper describes the relationship between the cumulative length of personal breastfeeding experience and the breastfeeding knowledge and attitudes of a cohort of Australian general practice (GP) registrars, as well as their confidence and perceived effectiveness assisting breastfeeding women. The Australian Breastfeeding Knowledge and Attitude Questionnaire containing demographic items, a 20‐item attitude scale and a 40‐item knowledge scale was distributed between February and May 2007 to Australian GP registrars in their final year of training. Participants with more than 52‐week cumulative personal (self or partner) breastfeeding experience had the highest mean knowledge score, had more positive attitudes, and were more confident and effective than all other participants. Parents with limited personal experience (≤26 weeks) had the poorest breastfeeding attitudes and their knowledge base was similar to participants with no personal experience. Confidence and perceived effectiveness when assisting breastfeeding women rose with increasing cumulative breastfeeding experience. Personal breastfeeding experience per se does not guarantee better breastfeeding knowledge or attitudes although increasing length of experience is related to higher knowledge, attitude, confidence and perceived effectiveness scores.
Perceived parenting behaviours predict young adolescents' nutritional intake and body fatness
Authors: Kim Mi‐Jeong , McIntosh William A. , Anding Jenna , Kubena Karen S. , Reed Debra B. , Moon Gap‐Soon
Published: September 2008

This study investigated whether perceptions of parenting behaviours predict young adolescents' nutritional intake and body fatness. The randomly selected study sample consisted of 106 13–15 years olds from Houston Metropolitan Statistical Area. Parenting style variables were created by cluster analysis and factor analysis. A two‐cluster solution for both maternal and paternal parenting style represented authoritative vs. non‐authoritative parenting. Two parenting dimension factors derived were maternal/paternal nurturing and control. For adolescents' energy and nutrient intake, greater maternal nurturing appeared to be most beneficial given its association with lower consumption of total kilocalorie and lower saturated fat intake. Paternal nurturing was associated with lower sodium intake, whereas paternal control predicted lower percentage of kilocalories from carbohydrate and percentage Dietary Reference Intake for dietary fibre, and greater percentage of kilocalories from total fat. Maternal authoritative parenting and lower maternal control over their adolescents may have protective effects against having heavier and fatter adolescents given their associations with adolescents' body weight, sub‐scapular skinfold, waist circumference, body mass index, and the tendencies of being at risk of overweight and being overweight. None of paternal parenting styles or dimensions appeared to be significantly related to adolescents' body fatness.
Percent body fat, skinfold thickness or body mass index for defining obesity or overweight, as a risk factor for asthma in schoolchildren: which one to use in epidemiological studies?
Authors: Garcia‐Marcos Luis , Valverde‐Molina Jose , Castaños Ortega Maria L. , Sanchez‐Solis Manuel , Martinez‐Torres Antonia E. , Castro‐Rodríguez Jose A.
Published: September 2008

None of the epidemiological studies indicating that obesity is a risk factor for asthma in schoolchildren have used the percent body fat (PBF) to define obesity. The present study compares the definition of obesity using body mass index (BMI), PBF and the raw sum of the thickness of four skinfolds (SFT) to evaluate this condition as a risk factor for asthma. All classes of children of the target ages of 6–8 years of all schools in four municipalities of Murcia (Spain) were surveyed. Participation rate was 70.2% and the number of children included in the study was 931. Height, weight and SFT (biceps, triceps, subscapular and suprailiac) were measured according to standard procedures. Current active asthma was defined from several questions of the International Study of Asthma and Allergies in Childhood questionnaire. Obesity was defined using two standard cut‐off points for BMI and PBF, and the 85th percentile for BMI, PBF and SFT. The highest quartile of each type of measurement was also compared with the lowest. A multiple logistic regression analysis was made for the various obesity definitions, adjusting for age, asthma in the mother and father and gender. The adjusted odds ratios of having asthma among obese children were different for boys and girls and varied across the different obesity definitions. For the standard cut‐off points of BMI they were 1.19 [95% confidence interval (CI) 0.41–3.43] for girls and 2.00 (95% CI 0.97–4.10) for boys; however, for PBF (boys 25%, girls 30%) the corresponding figures were 1.54 (95% CI 0.63–3.73) and 1.20 (95% CI 0.66–2.21). BMI, PBF and SFT showed more consistency between each other when using the other cut‐off points. BMI, PBF (except standard cut‐off points) and SFT produce relatively comparable results when analysing the interaction between obesity and asthma.
Effectiveness of a community‐based responsive feeding programme in rural Bangladesh: a cluster randomized field trial
Authors: Aboud Frances E. , Moore Anna C. , Akhter Sadika
Published: September 2008

Responsive complementary feeding, whereby the mother feeds her child in response to child cues of hunger state and psychomotor abilities, is a problem in some countries, and likely contributes to malnutrition. Interventions are needed to evaluate whether promoting responsive feeding would add any benefit. Using a cluster randomized field trial, we evaluated a six‐session educational programme that emphasized practice of two key behaviours, namely child self‐feeding and maternal responsiveness. One hundred mothers and their 12‐ to 24‐month‐olds attended the sessions as part of village clusters randomly assigned to the intervention group. A similar number of controls received sessions on foods to feed and nutritional disorders. Outcomes assessed at pre‐test, 2‐week post‐intervention and again 5‐months post‐intervention included weight, mouthfuls of food taken, self‐feeding and maternal responsiveness. Research assistants, blind to group assignment, observed and coded mother and child behaviours during the midday meal. Secondary measures included foods fed and feeding messages recalled. Analysis was based on intention to treat and accounted for clustering. Only 10% of each group was lost to follow‐up. Weight (d = 0.28), weight gain (d = 0.48) and child self‐feeding (d = 0.30) were significantly higher in the responsive feeding group. Mouthfuls of food eaten and maternal responsiveness were not significantly increased by the intervention. Mothers in the intervention gave their children more vegetables, and spontaneously recalled more feeding messages at the 5‐month follow‐up. These results provide evidence that self‐feeding and weight gain can improve by targeting specific behaviours, while maternal responsiveness may require more intensive strategies.
Infants admitted to neonatal units – interventions to improve breastfeeding outcomes: a systematic review 1990–2007
Authors: McInnes Rhona J. , Chambers Julie
Published: September 2008

This review aimed to identify interventions to promote breastfeeding or breast milk feeding for infants admitted to the neonatal unit.

The medical electronic databases were searched for papers listed between 1990 and June 2005 which had breastfeeding or breast milk as an outcome and which targeted infants who had been admitted to a neonatal unit, thus including the infant and/or their parents and/or neonatal unit staff. Only papers culturally relevant to the UK were included resulting in studies from the USA, Canada, Europe, Australia and New Zealand. This search was updated in December 2007 to include publications up to this date.

We assessed 86 papers in full, of which 27 ultimately fulfilled the inclusion criteria. The studies employed a range of methods and targeted different aspects of breastfeeding in the neonatal unit. Variations in study type and outcomes meant that there was no clear message of what works best but skin‐to‐skin contact and additional postnatal support seemed to offer greater advantage for the infant in terms of breastfeeding outcome. Galactogogues for mothers who are unable to meet their infants’ needs may also help to increase milk supply. Evidence of an effect from other practices, such as cup‐feeding on breastfeeding was limited; mainly because of a lack of research but also because few studies followed up the population beyond discharge from the unit.

Further research is required to explore the barriers to breastfeeding in this vulnerable population and to identify appropriate interventions to improve breastfeeding outcomes.
Recruiting a Diverse Group of Middle School Girls Into the Trial of Activity for Adolescent Girls
Authors: Elder John P. , Shuler LaVerne , Moe Stacey G. , Grieser Mira , Pratt Charlotte , Cameron Sandra , Hingle Melanie , Pickrel Julie L. , Saksvig Brit I. , Schachter Kenneth , Greer Susan , Guth Bothwell Elizabeth K.
Published: September 2008

Background:  School‐based study recruitment efforts are both time consuming and challenging. This paper highlights the recruitment strategies employed by the national, multisite Trial of Activity for Adolescent Girls (TAAG), a study designed to measure the effectiveness of an intervention to reduce the decline of physical activity levels among middle school–aged girls. TAAG provided a unique opportunity to recruit large cohorts of randomly sampled girls within 36 diverse middle schools across the United States.

Methods:  Key elements of the formative planning, coordination, and design of TAAG’s recruitment efforts included flexibility, tailoring, and the use of incentives. Various barriers, including a natural disaster, political tension, and district regulations, were encountered throughout the recruitment process, but coordinated strategies and frequent communication between the 6 TAAG sites were helpful in tailoring the recruitment process at the 36 intervention and control schools.

Results:  Progressively refined recruitment strategies and specific attention to the target audience of middle school girls resulted in overall study recruitment rates of 80%, 85%, and 89%, for the baseline, posttest, and follow‐up period, respectively.

Discussion:  The steady increase in recruitment rates over time is attributed to an emphasis on successful strategies and a willingness to modify less successful methods. Open and consistent communication, an increasingly coordinated recruitment strategy, interactive recruitment presentations, and participant incentives resulted in an effective recruitment campaign.
Schools and Neighborhoods: Organizational and Environmental Factors Associated With Crime in Secondary Schools*
Authors: Limbos Mary Ann P. , Casteel Carri
Published: September 2008

Background:  While crime and violence in schools are derived primarily from factors external to schools, violent behavior may also be aggravated by factors in the school environment, including the physical environment, its educational and social climate, and its organizational capacity and composition. The objective of this study is to examine the effect of the school’s organizational and educational environment on crime rates in secondary schools and to examine how neighborhood factors influence these relationships.

Methods:  School and neighborhood crime rates for 95 middle (MS) and high (HS) schools were calculated using data from the Los Angeles Unified School District (LAUSD) Police Department and Los Angeles Police Department, respectively. School‐level organizational and educational variables, including the academic performance index (API), were obtained from the California Department of Education. A measure of neighborhood dilapidation was created using variables collected on a neighborhood environmental survey. Linear regression was used to examine the relationship between organizational and educational school variables and school crime rates. Community crime and dilapidation were added to the model to examine the influence of the school‐community context relationships.

Results:  HS had higher crime rates than MS. As the percentage of certified teachers and student to staff ratios increased, school crime decreased (p < .01). An API of below basic performance was significantly associated with increasing school crime rates (p < .05). Neighborhood crime was not significantly associated with school crime, although dilapidation was positively and significantly associated with school crime even after controlling for community crime (p < .05).

Conclusions:  Both school‐ and neighborhood‐level factors were associated with increasing crime rates in secondary schools. School violence prevention efforts should include school and community partnerships to address these potentially modifiable factors.
High School Youth and Suicide Risk: Exploring Protection Afforded Through Physical Activity and Sport Participation
Authors: Taliaferro Lindsay A. , Rienzo Barbara A. , Miller M. David , Pigg R. Morgan , Dodd Virginia J.
Published: September 2008

Background:  Suicide ranks as the third leading cause of death for adolescents. Recent data from the Centers for Disease Control and Prevention (CDC) indicate that the adolescent suicide rate increased 18% between 2003 and 2004. Sport may represent a promising protective factor against adolescent suicide. This study examined the relative risk of hopelessness and suicidality associated with physical activity and sport participation.

Methods:  Data from the CDC’s 2005 Youth Risk Behavior Survey were analyzed. Logistic regression modeling was used to compare the odds of hopelessness and suicidality in students who engaged in various levels of physical activity to inactive students. Similar analyses were performed comparing risks of athletes to nonathletes, and the risks of highly involved athletes to nonathletes.

Results:  Findings showed that frequent, vigorous activity reduced the risk of hopelessness and suicidality among male adolescents. However, low levels of activity actually increased the risk of feeling hopeless among young females. Yet, for both males and females, sport participation protected against hopelessness and suicidality.

Conclusion:  These findings indicate that involvement in sport confers unique psychosocial benefits that protect adolescents against suicidality. Findings suggest that mechanisms other than physical activity contribute to the protective association between sport and reduced suicidality. Social support and integration may account for some of the differences found in suicidality between athletes and nonathletes.
Violence and Drug Use in Rural Teens: National Prevalence Estimates From the 2003 Youth Risk Behavior Survey
Authors: Johnson Andrew O. , Mink Michael D. , Harun Nusrat , Moore Charity G. , Martin Amy B. , Bennett Kevin J.
Published: September 2008

Objectives:  The purpose of this study was to compare national estimates of drug use and exposure to violence between rural and urban teens.

Methods:  Twenty‐eight dependent variables from the 2003 Youth Risk Behavior Survey were used to compare violent activities, victimization, suicidal behavior, tobacco use, alcohol use, and illegal drug use across rural, urban, and suburban teens across the country.

Results:  Overall, rural teens were equally or more likely than both suburban and urban teens to report experiencing many measures of violent behavior, victimization, suicide behaviors, and drug use. Among all teens, nonwhites reported equal or higher rates of violent behavior and victimization than whites, but these associations disappeared within the rural‐only population.

Conclusions:  Rural areas do not appear to provide a strongly protective effect against risk behaviors in teens and may be a risk factor in itself. Community prevention efforts should focus on reaching rural areas and segmenting program content based on need. Where white teens might benefit from an emphasis on preventing tobacco and alcohol use, nonwhite teens would benefit from an emphasis on preventing violence and victimization.