bluuebunny/crossref_metadata_2025 huggingface dataset:
Decompositions of the polyhedral product functor with applications to moment-angle complexes and related spaces
Authors: Bahri A. , Bendersky M. , Cohen F. R. , Gitler S.
Published: July 2009

This article gives a natural decomposition of the suspension of a generalized moment-angle complex or partial product space which arises as the polyhedral product functor described below. The introduction and application of the smash product moment-angle complex provides a precise identification of the stable homotopy type of the values of the polyhedral product functor. One direct consequence is an analysis of the associated cohomology. For the special case of the complements of certain subspace arrangements, the geometrical decomposition implies the homological decomposition in earlier work of others as described below. Because the splitting is geometric, an analogous homological decomposition for a generalized moment-angle complex applies for any homology theory. Implied, therefore, is a decomposition for the Stanley–Reisner ring of a finite simplicial complex, and natural generalizations.
Structure-based discovery and description of plant and animal
Helitrons
Authors: Yang Lixing , Bennetzen Jeffrey L.
Published: July 2009

Helitrons
are recently discovered eukaryotic transposons that are predicted to amplify by a rolling-circle mechanism. They are present in most plant and animal species investigated, but were previously overlooked partly because they lack terminal repeats and do not create target site duplications.
Helitrons
are particularly abundant in flowering plants, where they frequently acquire, and sometimes express, 1 or more gene fragments. A structure-based search protocol was developed to find
Helitrons
and was used to analyze several plant and animal genomes, leading to the discovery of hundreds of new
Helitrons
. Analysis of these
Helitrons
has uncovered mechanisms of element evolution, including end creation and sequence acquisition. Preferential accumulation in gene-poor regions and target site specificities were also identified. Overall, these studies provide insights into the transposition and evolution of
Helitrons
and their contributions to evolved gene content and genome structure.
Ultrasensitive detection of nitric oxide at 5.33 μm by using external cavity quantum cascade laser-based Faraday rotation spectroscopy
Authors: Lewicki Rafał , Doty James H. , Curl Robert F. , Tittel Frank K. , Wysocki Gerard
Published: July 2009

A transportable prototype Faraday rotation spectroscopic system based on a tunable external cavity quantum cascade laser has been developed for ultrasensitive detection of nitric oxide (NO). A broadly tunable laser source allows targeting the optimum Q
3/2
(3/2) molecular transition at 1875.81 cm
−1
of the NO fundamental band. For an active optical path of 44 cm and 1-s lock-in time constant minimum NO detection limits (1σ) of 4.3 parts per billion by volume (ppbv) and 0.38 ppbv are obtained by using a thermoelectrically cooled mercury–cadmium–telluride photodetector and liquid nitrogen-cooled indium–antimonide photodetector, respectively. Laboratory performance evaluation and results of continuous, unattended monitoring of atmospheric NO concentration levels are reported.
Shock-synthesized hexagonal diamonds in Younger Dryas boundary sediments
Authors: Kennett Douglas J. , Kennett James P. , West Allen , West G. James , Bunch Ted E. , Culleton Brendan J. , Erlandson Jon M. , Que Hee Shane S. , Johnson John R. , Mercer Chris , Shen Feng , Sellers Marilee , Stafford Thomas W. , Stich Adrienne , Weaver James C. , Wittke James H. , Wolbach Wendy S.
Published: July 2009

The long-standing controversy regarding the late Pleistocene megafaunal extinctions in North America has been invigorated by a hypothesis implicating a cosmic impact at the Ållerød-Younger Dryas boundary or YDB (≈12,900 ± 100 cal BP or 10,900 ± 10014C years). Abrupt ecosystem disruption caused by this event may have triggered the megafaunal extinctions, along with reductions in other animal populations, including humans. The hypothesis remains controversial due to absence of shocked minerals, tektites, and impact craters. Here, we report the presence of shock-synthesized hexagonal nanodiamonds (lonsdaleite) in YDB sediments dating to ≈12,950 ± 50 cal BP at Arlington Canyon, Santa Rosa Island, California. Lonsdaleite is known on Earth only in meteorites and impact craters, and its presence strongly supports a cosmic impact event, further strengthened by its co-occurrence with other nanometer-sized diamond polymorphs (n-diamonds and cubics). These shock-synthesized diamonds are also associated with proxies indicating major biomass burning (charcoal, carbon spherules, and soot). This biomass burning at the Younger Dryas (YD) onset is regional in extent, based on evidence from adjacent Santa Barbara Basin and coeval with broader continent-wide biomass burning. Biomass burning also coincides with abrupt sediment mass wasting and ecological disruption and the last known occurrence of pygmy mammoths (Mammuthus exilis) on the Channel Islands, correlating with broader animal extinctions throughout North America. The only previously known co-occurrence of nanodiamonds, soot, and extinction is the Cretaceous-Tertiary (K/T) impact layer. These data are consistent with abrupt ecosystem change and megafaunal extinction possibly triggered by a cosmic impact over North America at ≈12,900 ± 100 cal BP.
The N-end rule pathway controls multiple functions during
Arabidopsis
shoot and leaf development
Authors: Graciet Emmanuelle , Walter Franziska , Maoiléidigh Diarmuid Ó , Pollmann Stephan , Meyerowitz Elliot M. , Varshavsky Alexander , Wellmer Frank
Published: July 2009

The ubiquitin-dependent N-end rule pathway relates the in vivo half-life of a protein to the identity of its N-terminal residue. This proteolytic system is present in all organisms examined and has been shown to have a multitude of functions in animals and fungi. In plants, however, the functional understanding of the N-end rule pathway is only beginning. The N-end rule has a hierarchic structure. Destabilizing activity of N-terminal Asp, Glu, and (oxidized) Cys requires their conjugation to Arg by an arginyl–tRNA–protein transferase (R-transferase). The resulting N-terminal Arg is recognized by the pathway's E3 ubiquitin ligases, called “N-recognins.” Here, we show that the
Arabidopsis
R-transferases AtATE1 and AtATE2 regulate various aspects of leaf and shoot development. We also show that the previously identified N-recognin PROTEOLYSIS6 (PRT6) mediates these R-transferase-dependent activities. We further demonstrate that the arginylation branch of the N-end rule pathway plays a role in repressing the meristem-promoting
BREVIPEDICELLUS
(
BP
) gene in developing leaves.
BP
expression is known to be excluded from
Arabidopsis
leaves by the activities of the ASYMMETRIC LEAVES1 (AS1) transcription factor complex and the phytohormone auxin. Our results suggest that AtATE1 and AtATE2 act redundantly with AS1, but independently of auxin, in the control of leaf development.
Data Gathering Schedule for Minimal Aggregation Time in Wireless Sensor Networks
Authors: Chen Xujin , Hu Xiaodong , Zhu Jianming
Published: July 2009

Data aggregation promises a new paradigm for gathering data via collaboration among wireless sensors deployed over a large geographical region. Many real-time applications impose stringent delay requirements and ask for time-efficient schedules of data gathering in which data sensed at sensors are aggregated at intermediate sensors along the way towards the data sink. The Minimal Aggregation Time (MAT) problem is to find the schedule that routes data appropriately and has the shortest time for all requested data to be aggregated and sent to the data sink.

In this article we consider the MAT problem with collision-free transmission where a sensor can not receive any data if more than one sensors within its transmission range send data at the same time. We first prove that the MAT problem is NP-hard even if all sensors are deployed on a grid. We then propose a (Δ −1)-approximation algorithms for the MAT problem, where Δ is the maximum number of sensors within the transmission range of any sensor. By exploiting the geometric nature of wireless sensor networks, we obtain some better theoretical results for some special cases. We also simulate the proposed algorithm. The numerical results show that our algorithm has much better performance in practice than the theoretically proved guarantees and outperforms other existing algorithms.
Coverage and Reliability of Randomly Distributed Sensor Systems with Heterogeneous Detection Range
Authors: Rowe Errol G. , Wettergren Thomas A.
Published: July 2009

In this article, we examine the coverage and reliability of distributed sensor networks that are designed for surveillance applications. In particular, we examine a model of sensor network coverage based on Poisson processes, and illustrate how this model combines with standard reliability models to provide estimates of field degradation over time. The results of the article illustrate how the number of sensors required changes with respect to reliability criteria, and how to design and re-seed sensor fields to maintain a minimal level of surveillance coverage. The formulation in the article is presented analytically, and all results are compared to numerical simulations.
The Role of Th17 in Neuroimmune Disorders: Target for CAM Therapy. Part I
Authors: Vojdani Aristo , Lambert Jama
Published: July 2009

CD4+ effector cells, based on cytokine production, nuclear receptors and signaling pathways, have been categorized into four subsets. T‐helper‐1 cells produce IFN‐γ, TNF‐β, lymphotoxin and IL‐10; T‐helper‐2 cells produce IL‐4, IL‐5, IL‐10, IL‐13, IL‐21 and IL‐31; T‐helper‐3, or regulatory T‐cells, produce IL‐10, TGF‐β and IL‐35; and the recently discovered T‐helper‐17 cell produces IL‐17, IL‐17A, IL‐17F, IL‐21, IL‐26 and CCL20. By producing IL‐17 and other signaling molecules, Th17 contributes to the pathogenesis of multiple autoimmune diseases including allergic inflammation, rheumatoid arthritis, autoimmune gastritis, inflammatory bowel disease, psoriasis and multiple sclerosis. In this article, we review the differential regulation of inflammation in different tissues with a major emphasis on enhancement of neuroinflammation by local production of IL‐17 in the brain. By understanding the role of pathogenic factors in the induction of autoimmune diseases by Th17 cells, CAM practitioners will be able to design CAM therapies targeting Th17 and associated cytokine activities and signaling pathways to repair the intestinal and blood‐brain barriers for their patients with autoimmunities, in particular, those with neuroinflammation and neurodegeneration.
Fermented Wheat Germ Extract (Avemar) in the Treatment of Cardiac Remodeling and Metabolic Symptoms in Rats
Authors: Iyer Abishek , Brown Lindsay
Published: July 2009

Avemar, a product of industrial fermentation of wheat germ with a standardized content of benzoquinone and plant flavonoids, has been tested as an anti‐cancer and immunomodulatory dietary supplement. Proposed mechanisms include anti‐oxidant and anti‐inflammatory actions. This study has determined whether these actions of Avemar may also be useful in the treatment of cardiovascular diseases. Two experimental rat models of cardiovascular remodeling were used in this project: the deoxycorticosterone acetate (DOCA)‐salt‐induced model of chronic hypertension (study I) and a high‐carbohydrate/high‐fat diet‐induced model producing chronic symptoms of the metabolic syndrome and its associated cardiovascular complications (study II). Our results in these rat models of hypertension and diet‐induced obesity show that treatment with Avemar improved cardiac function, decreased macrophage infiltration resulting in decreased collagen deposition in the ventricular myocardium, reversed an increased stiffness of the left ventricle in the diseased hearts and attenuated increased plasma malondialdehyde concentrations. In addition to the changes in the heart, Avemar reversed glucose intolerance, normalized systolic blood pressure and decreased visceral fat deposition in rats fed a high‐fat/high‐carbohydrate diet. In conclusion, the fermented wheat germ extract Avemar has a potential role in attenuating chronic hypertension, diabetes or metabolic syndrome‐induced cardiovascular symptoms along with metabolic abnormalities such as glucose tolerance and obesity.
Putting Audit Approaches in Context: The Case of Business Risk Audits in Jordan
Authors: Abdullatif Modar , Al‐Khadash Husam Aldeen
Published: July 2009

Large international audit firms are increasingly expanding their activities around the world and increasingly promoting the concept of a similar quality audit to be performed by all their worldwide offices and member firms. This strategy includes developing and using a similar audit approach globally. This study surveys the views of Jordanian auditors, mainly from audit firms with international affiliations, about how such an international approach, with emphasis on the currently popular business risk approach, is applied in practice by Jordanian audit firms and how appropriate and practical the application of such an international approach to auditing is in different contexts. The results of the study show that the business risk approach has been generally adopted by the larger Jordanian audit firms to varying extents, especially those which are full members of an international audit firm network. However, audit clients in Jordan face too many business risks, especially because of poor control systems, poor corporate governance structures, and unclear or non‐existent corporate strategies and objectives. These risks have to be addressed by the business risk approach under very low audit fees. Such factors have led to the business risk approach not being applied in the way that the large international audit firms intended, and not achieving the approach's main objectives, leaving the audit profession with the question of how appropriate it is to adopt an international audit approach in different contexts.
External Auditing vs Statutory Committee Auditing: The Italian Evidence
Authors: Mariani Laura , Tettamanzi Patrizia , Corno Fabio
Published: July 2009

The Italian Corporate Law Reform introduced a compulsory independent external auditor. In the past, only listed companies were required to be audited by external auditors, while non‐listed companies were audited by the Board of Statutory Auditors regulated by the Italian Civil Code. The reform separated the responsibilities of administrative and financial auditing: statutory auditors were left in charge of administrative auditing, while financial auditing was assigned to external auditors, leaving a selected number of companies with the possibility of keeping the statutory auditors in charge of financial auditing as well. An empirical analysis was conducted on a sample of companies, aimed at assessing whether external auditors – compared to statutory auditors – generally granted a higher quality of auditing. To assess the quality of auditing, the reliability of annual reports was considered, examining the discretionary accrual levels.
When Auditors Err: How Mistake Significance and Superiors' Historical Reactions Influence Auditors' Likelihood to Admit a Mistake
Authors: Stefaniak Chad , Robertson Jesse C.
Published: July 2009

The procedures performed by staff auditors are a critical component of the audit process, and mistakes in these procedures could jeopardize opinions if they are not communicated. While professional standards instruct auditors to report their errors, auditors have incentives to withhold information about mistakes because they are protective of their professional images. These conflicting pressures are examined by investigating the effects of mistake significance and superiors' historical reactions to mistake admissions on the likelihood that staff auditors will admit mistakes. We find an interaction suggesting that staff auditors are more likely to admit errors when their superiors have reacted positively, regardless of error significance. Conversely, staff auditors are less likely to admit apparently insignificant errors when their superiors have reacted negatively to prior mistakes.
The Relationship between Demographic Variables and Ethical Decision Making of Trainee Accountants
Authors: Pierce Bernard , Sweeney Breda
Published: July 2009

This study examines the impact of a range of demographic variables (gender, firm size, degree type, level of education, length of experience, age and work area) on ethical intentions, ethical judgement, perceived ethical intensity and perceived ethical culture. Cases containing information on four types of time pressure‐induced auditor dysfunctional behaviours were distributed to trainee accountants attending a professional education programme of the Institute of Chartered Accountants in Ireland. The findings suggest that gender, firm size and degree type had a significant association with ethical decision making. These variables also had a significant association with perceived ethical intensity as did work area. Gender, firm size, level of education and length of experience showed evidence of a significant association with perceived ethical culture. Implications of the findings and areas for further research are discussed.
Systematic review: the short‐term and long‐term efficacy of adalimumab following discontinuation of infliximab
Authors: MA C. , PANACCIONE R. , HEITMAN S. J. , DEVLIN S. M. , GHOSH S. , KAPLAN G. G.
Published: July 2009

Background  Therapy with adalimumab has been shown to be effective in Crohn’s disease (CD) patients who have lost response or are intolerant to infliximab.

Aim  To determine the efficacy of adalimumab in CD patients who discontinued infliximab through a systematic review.

Methods  Electronic searches of EMBASE and MEDLINE databases up to May 1, 2009, as well as abstracts from the AGA (2006–2008), ACG (2006–2007), UEGW (2006–2008) and CDDW (2006–2009) identified randomized‐controlled trials (RCT) or open‐labelled cohorts (OLC) evaluating the short‐term and/or long‐term efficacy of adalimumab in infliximab failures. The response rates for short‐term (clinical response and remission at 4 weeks) and long‐term (remission at 6 and 12 months) efficacy were considered.

Results  A total of 1810 CD patients were identified among the 15 studies (2 RCT and 13 OLC). The majority of studies evaluated CD patients who either lost response or were intolerable to infliximab, although five OLCs permitted patients refractory to infliximab. Short‐term clinical response (n = 9 articles) ranged from 41% to 83%. Long‐term clinical remission at 12 months (n = 8 articles) ranged from 19% to 68%. The occurrence of severe adverse events ranged from 0% to 19% and four patients died.

Conclusions  Current RCT and OLC evidence suggest that adalimumab is an efficacious therapy for CD patients who discontinue infliximab.
Associations between decay‐accelerating factor polymorphisms and allergic respiratory diseases
Authors: Kawai T. , Takeshita S. , Imoto Y. , Matsumoto Y. , Sakashita M. , Suzuki D. , Shibasaki M. , Tamari M. , Hirota T. , Arinami T. , Fujieda S. , Noguchi E.
Published: July 2009

Background
Allergic diseases such as asthma and allergic rhinitis are major causes of morbidity in developed countries. The pathology underlying allergic respiratory diseases is considered to be IgE‐mediated type I allergy characterized by mucosal inflammation that occurs in response to allergen exposure. They are common diseases involving a complex inheritance. Complement systems are known to play an important role in allergic diseases. Decay‐accelerating factor (DAF) is important for the regulation of the complement system and is a good candidate for determining the susceptibility to allergic diseases.

Objective
The present study aimed to investigate whether polymorphisms in the DAF gene are associated with allergic respiratory diseases in the Japanese population.

Methods
We performed mutation screenings of DAF and conducted a tag single‐nucleotide polymorphisms (SNP) association analysis for 684 unrelated adult individuals with seasonal allergic rhinitis (SAR) with Japanese ceder pollen, 188 mite‐sensitive adults with asthma, and 346 unrelated non‐allergic healthy controls.

Results
DAF is located in the tight linkage disequilibrium (LD) block spanning 62 kb. The tag SNP analysis revealed that rs10746463 was significantly associated with SAR (P=0.00033) and mite‐sensitive adult asthma (P=0.044). The rs2564978 and rs3841376 haplotypes, which are located in the promoter region of DAF, were in complete LD with rs10746463 (r2=1). Luciferase reporter assays with constructs containing the 5′ flanking regions of DAF showed that the plasmid with rs2564978 C/rs3841376 deletion (the risk haplotype) had a statistically significantly lower transcriptional activity than that containing the rs2564978 T/rs3841376 insertion.

Conclusions
Our results suggest that DAF is one of the genes involved in conferring susceptibility to allergic respiratory diseases and show that decreased levels of DAF may be associated with the enhanced specific IgE responses occurring in allergic diseases in the Japanese population.
The impact of soil carbon management on soil macropore structure: a comparison of two apple orchard systems in New Zealand
Authors: Deurer M. , Grinev D. , Young I. , Clothier B. E. , Müller K.
Published: July 2009

We analysed the long‐term effect of the addition of organic carbon (C) on the macropore structure of topsoils. For this purpose we compared the top 50 mm in the tree rows of an organic apple orchard with those in an adjacent conventional orchard with the same soil type, texture and previous land‐use history in New Zealand. After 12 years the topsoils of the organic orchard had 32% more soil organic carbon (SOC) sequestered than those of the conventional, integrated orchard because of regular compost applications and grass coverage. We quantified the macropore structure (macropores = pores > 0.3 mm) of nine undisturbed soil columns (43 mm long, 20 × 17 mm in the plane) within each orchard using 3D X‐ray computed tomography. The macroporosity (7.5 ± 2.1%) of the organic orchard soil was significantly greater than that of the integrated orchard (2.4 ± 0.5%). The mean macropore radius was similar in the organic and integrated systems, with 0.41 ± 0.02 mm and 0.39 ± 0.01 mm, respectively. The connectivity of macropores tended to be greater in the organic than in the integrated system, but this was not statistically significant. The pronounced soil C management in the organic orchard increased both the formation of macropores by roots and a larger fresh weight of anecic earthworms, and the stabilization of the macropore structure was increased by a larger aggregate stability and microbial biomass compared with those of the integrated orchard. We simulated the diffusion through the measured pore structures of segments of the soil columns. The segments had the length of the mean aggregate size of the soils. The relative diffusion coefficients at this aggregate scale were significantly greater in the organic (0.024 ± 0.0009) than in the integrated (0.0056 ± 0.008) orchard. In a regression analysis with both the porosity and connectivity of macropores as significant variables, 76% of the variability of the relative diffusion coefficients was explained in the integrated, and, with the porosity as the only significant factor, 71% of the variability in the organic orchard. We hypothesize that a greater relative diffusion coefficient at the aggregate scale would reduce nitrous oxide (N2O) production and emission in a wet soil and suggest that soil C management combats climate change directly by sequestering C and indirectly in the form of a reduction of N2O emissions, by creating more macropores.
Winners and losers of conservation policies for European eel, Anguilla anguilla: an economic welfare analysis for differently specialised eel anglers
Authors: DOROW M. , BEARDMORE B. , HAIDER W. , ARLINGHAUS R.
Published: July 2009

Abstract  Recreational specialisation theory was coupled with a discrete choice experiment to understand eel, Anguilla anguilla L., angler’s heterogeneity in their reaction to regulatory changes and the associated welfare changes. Differently specialised eel anglers exhibited distinct preferences for catch variables and eel angling regulations. All anglers preferred slightly to moderately stricter regulations than are currently in place; however, such policies particularly benefited casual eel anglers. In contrast, advanced eel anglers would be most penalised by highly restrictive regulations as indicated by substantial reductions in economic welfare. Aversions to stricter regulations found for advanced anglers contradicted predictions from specialisation theory. From an eel management perspective, the implementation of some simple tools such as increased minimum‐size limits will reduce angling mortality on eel and simultaneously increase the welfare of anglers. By contrast, highly restrictive eel angling regulations will result in considerable economic welfare losses of several million € per year for northern Germany alone.
Fungal C translocation restricts N‐mineralization in heterogeneous environments
Authors: Boberg Johanna B. , Finlay Roger D. , Stenlid Jan , Lindahl Björn D.
Published: July 2009

1. In forest soils, fungi generally dominate the decomposer community, but their specific, filamentous physiology is often not recognized in nitrogen (N) cycling models. Many litter degrading fungi form large mycelia and have a well‐developed capacity to translocate resources within their mycelia. Fungi may thus connect substrates that differ with respect to carbon (C) and nitrogen (N) availability and, thereby, overcome local resource limitation through translocation.

2. Here we test whether the ability of fungi to translocate carbohydrates within their mycelia prevents local C limitation in a low C:N ratio substrate, thereby reducing N mineralization. The capacity of fungi to translocate N to a high C:N ratio substrate in order to increase the decomposition, was also assessed. Two litter decomposing fungi, Marasmius androsaceus and Mycena epipterygia were grown in axenic laboratory microcosms containing spatially separated substrates: pine needles (C:N = 135) and glycine (C:N = 2).

3. In the absence of needles both fungi mineralized the glycine N. When connecting the two substrates, both fungi were able to overcome local C‐deficiency on the glycine medium by translocating carbohydrates from the needles. In the presence of needles, N mineralization from glycine was negligible, although the glycine was utilized. Only trace amounts of N were translocated from glycine to the needles.

4. A basic assumption of N cycling models is that substrates of different qualities decompose in an independent manner. Our observations imply that this assumption may be violated in heterogenic environments dominated by fungi.
Biot dispersion for P‐ and S‐wave velocities in partially and fully saturated sandstones
Authors: King M.S. , Marsden J.R. , Dennis J.W.
Published: July 2009

Ultrasonic compressional‐ and shear‐wave velocities have been measured on 34 samples of sandstones from hydrocarbon reservoirs. The sandstones are all of low clay content, high porosity, and cover a wide range of permeabilities. They were measured dry and brine‐saturated under hydrostatic effective stresses of 10, 20 and 40 MPa. For eight of the sandstones, ultrasonic velocity measurements were made at different partial water saturations in the range from dry to fully saturated. The Gassmann–Biot theory is found to account for most of the changes in velocities at high effective stress levels when the dry sandstones are fully saturated with brine, provided the lower velocities resulting when the dry sandstone initially adsorbs small amounts of moisture are used to determine the elastic properties of the ‘dry’ sandstone. At lower effective stress levels, local flow phenomena due to the presence of open microcracks are assumed to be responsible for measured velocities higher than those predicted by the theory. The partial saturation results are modelled fairly closely by the Gassmann–Biot theory, assuming heterogeneous saturation for P‐waves.
Sites of initial bleeding episodes, mode of delivery and age of diagnosis in babies with haemophilia diagnosed before the age of 2 years: a report from The Centers for Disease Control and Prevention’s (CDC) Universal Data Collection (UDC) project
Authors: KULKARNI R. , SOUCIE J. M. , LUSHER J. , PRESLEY R. , SHAPIRO A. , GILL J. , MANCO‐JOHNSON M. , KOERPER M. , MATHEW P. , ABSHIRE T. , DIMICHELE D. , HOOTS K. , JANCO R. , NUGENT D. , GERAGHTY S. , EVATT B. ,   the Haemophilia Treatment Center Network Investigators
Published: July 2009

Summary.  Lack of detailed natural history and outcomes data for neonates and toddlers with haemophilia hampers the provision of optimal management of the disorder. We report an analysis of prospective data collected from 580 neonates and toddlers aged 0–2 years with haemophilia enrolled in the Universal Data Collection (UDC) surveillance project of the Centers for Disease Control and Prevention (CDC). This study focuses on a cohort of babies with haemophilia whose diagnosis was established before the age of two. The mode of delivery, type and severity of haemophilia, onset and timing of haemorrhages, site(s) of bleeding, provision of prophylaxis with coagulation factor replacement therapy, and the role played by the federally funded Haemophilia Treatment Centers (HTC) in the management of these infants with haemophilia were evaluated. Seventy‐five per cent of haemophilic infants were diagnosed early, in the first month of life, especially those with a family history or whose mothers were known carriers; infants of maternal carriers were more likely to be delivered by C‐section. Involvement of an HTC prior to delivery resulted in avoidance of the use of assisted deliveries with vacuum and forceps. Bleeding from the circumcision site was the most common haemorrhagic complication, followed by intra‐ and extra‐cranial haemorrhages and bleeding from heel stick blood sampling. Eight per cent of the infants were administered factor concentrate within 24 h of birth; more than half were treated to prevent bleeding. This study highlights the significant rate and the sites of initial bleeding unique to very young children with haemophilia and underscores the need for research to identify optimal evidence‐based recommendations for their management.
Microbial, chemical and rheological properties of laban  (cultured milk)
Authors: Guizani Nejib , Kasapis Stefan , Al‐Ruzeiki Mohammed
Published: July 2009

Summary The chemical, microbial and rheological properties of commercial and home‐made laban were investigated in an effort to contribute to the standardization of the product. Commercial laban has higher fat, protein and total solids content but was less acidic than traditional laban. Lactobacilli dominate in the former, whereas lactococci are found mainly in the latter. Four micro‐organisms classified as Lactococcus lactis ssp lactis, Lactococcus lactis ssp lactis biovar diacetylactis, Lactococcus lactis ssp cremoris and Lactobacillus plantarum were responsible for the fermentation of traditional laban, whereas three micro‐organisms, namely: Lactobacillus acidophilus, bifidobacteria and Streptococcus thermophilus were responsible for the production of commercial laban. Unlike the commercial preparation, traditional laban contained considerable numbers of yeasts and moulds and was contaminated with coliforms and fecal coliforms. The rheological profile of a semi‐dilute solution was more pronounced in the home‐made laban with both preparations flowing from the first Newtonian plateau and the power law region to the second Newtonian plateau with increasing shear rate.
Elderly peoples’ experience of nursing care after a stroke: from a gender perspective
Authors: Andersson Åsa , Hansebo Görel
Published: July 2009

Title.  Elderly peoples’ experience of nursing care after a stroke: from a gender perspective.

Aim.  This paper is a report of a study conducted to explore, from a gender perspective, older people’s experiences of nursing care after a stroke.

Background.  Little attention has been given to gender differences in nursing care. The majority of people who have a stroke are older. Improving knowledge of the gender perspectives of older men and women regarding nursing care after stroke is crucial.

Method.  This was a qualitative study based on interviews with five women and five men between 66 and 75 years of age, who had received nursing care at a ward for stroke rehabilitation. The data were collected in 2006. Qualitative content analysis of the interviews was carried out.

Findings.  A main theme and five categories, all common to both men and women, were identified. The main theme, to promote recovery of the body, encompassed the categories. There were, however, gender differences in how the nursing care received was experienced. The ways patients experienced nursing care seemed to be linked with their lives as women and men before they had the stroke. Their perceptions are linked with their lives as women and men before they had their stroke. Both men and women will reclaim former abilities but what they perceive to be the goals of nursing care and rehabilitation may differ.

Conclusion.  Nurses need to increase their awareness and knowledge concerning the similarities and gender differences in the experiences and needs of older people, both men and women.
Invasion success depends on invader body size in a size‐structured mixed predation–competition community
Authors: Schröder Arne , Nilsson Karin A. , Persson Lennart , Van Kooten Tobias , Reichstein Birte
Published: July 2009

1. The size of an individual is an important determinant of its trophic position and the type of interactions it engages in with other heterospecific and conspecific individuals. Consequently an individual’s ecological role in a community changes with its body size over ontogeny, leading to that trophic interactions between individuals are a size‐dependent and ontogenetically variable mixture of competition and predation.

2. Because differently sized individuals thus experience different biotic environments, invasion success may be determined by the body size of the invaders. Invasion outcome may also depend on the productivity of the system as productivity influences the biotic environment.

3. In a laboratory experiment with two poeciliid fishes the body size of the invading individuals and the daily amount of food supplied were manipulated.

4. Large invaders established persistent populations and drove the resident population to extinction in 10 out of 12 cases, while small invaders failed in 10 out of 12 trials. Stable coexistence was virtually absent. Invasion outcome was independent of productivity.

5. Further analyses suggest that small invaders experienced a competitive recruitment bottleneck imposed on them by the resident population. In contrast, large invaders preyed on the juveniles of the resident population. This predation allowed the large invaders to establish successfully by decreasing the resident population densities and thus breaking the bottleneck.

6. The results strongly suggest that the size distribution of invaders affects their ability to invade, an implication so far neglected in life‐history omnivory systems. The findings are further in agreement with predictions of life‐history omnivory theory, that size‐structured interactions demote coexistence along a productivity gradient.
The tetraspan protein Dni1p is required for correct membrane organization and cell wall remodelling during mating in Schizosaccharomyces pombe
Authors: Clemente‐Ramos José Ángel , Martín‐García Rebeca , Sharifmoghadam Mohammad R. , Konomi Mami , Osumi Masako , Valdivieso M.‐Henar
Published: July 2009

In fungi, success of mating requires that both cells agglutinate, modify their extracellular envelopes, and fuse their plasma membranes and nuclei to produce a zygote. Here we studied the role of the Schizosaccharomyces pombe Dni1 protein in the cell fusion step of mating. Dni1p is a tetraspan protein bearing a conserved cystein motif similar to that present in fungal claudin‐related proteins. Dni1p expression is induced during mating and Dni1p concentrates as discrete patches at the cell–cell contact area and along the mating bridge. Proper Dni1p localization depends on Fus1p, actin and integrity of lipid rafts. In dni1Δ mutants, cell differentiation and agglutination are as efficient as in the wild‐type strain, but cell fusion is significantly reduced at temperatures above 25°C. We found that the defect in cell fusion was not associated with an altered cytoskeleton, with an abnormal distribution of Fus1p, or with a defect in calcium accumulation, but with a severe disorganization of the plasma membrane and cell wall at the area of cell–cell contact. These results show that Dni1p plays a relevant role in co‐ordinating membrane organization and cell wall remodelling during mating, a function that has not been described for other proteins in the fission yeast.
The crystal structure of the TolB box of colicin A in complex with TolB reveals important differences in the recruitment of the common TolB translocation portal used by group A colicins
Authors: Zhang Ying , Li Chan , Vankemmelbeke Mireille N. , Bardelang Philip , Paoli Max , Penfold Christopher N. , James Richard
Published: July 2009

Interaction of the TolB box of Group A colicins with the TolB protein in the periplasm of Escherichia coli cells promotes transport of the cytotoxic domain of the colicin across the cell envelope. The crystal structure of a complex between a 107‐residue peptide (TA1–107) of the translocation domain of colicin A (ColA) and TolB identified the TolB box as a 12‐residue peptide that folded into a distorted hairpin within a central canyon of the β‐propeller domain of TolB. Comparison of this structure with that of the colicin E9 (ColE9) TolB box–TolB complex, together with site‐directed mutagenesis of the ColA TolB box residues, revealed important differences in the interaction of the two TolB boxes with an overlapping binding site on TolB. Substitution of the TolB box residues of ColA with those of ColE9 conferred the ability to competitively recruit TolB from Pal but reduced the biological activity of the mutant ColA. This datum explains (i) the difference in binding affinities of ColA and ColE9 with TolB, and (ii) the inability of ColA, unlike ColE9, to competitively recruit TolB from Pal, allowing an understanding of how these two colicins interact in a different way with a common translocation portal in E. coli cells.
RNase II is important for A‐site mRNA cleavage during ribosome pausing
Authors: Garza‐Sánchez Fernando , Shoji Shinichiro , Fredrick Kurt , Hayes Christopher S.
Published: July 2009

In Escherichia coli, translational arrest can elicit cleavage of codons within the ribosomal A site. This A‐site mRNA cleavage is independent of RelE, and has been proposed to be an endonucleolytic activity of the ribosome. Here, we show that the 3′→5′ exonuclease RNase II plays an important role in RelE‐independent A‐site cleavage. Instead of A‐site cleavage, translational pausing in ΔRNase II cells produces transcripts that are truncated +12 and +28 nucleotides downstream of the A‐site codon. Deletions of the genes encoding polynucleotide phosphorylase (PNPase) and RNase R had little effect on A‐site cleavage. However, PNPase overexpression restored A‐site cleavage activity to ΔRNase II cells. Purified RNase II and PNPase were both unable to directly catalyse A‐site cleavage in vitro. Instead, these exonucleases degraded ribosome‐bound mRNA to positions +18 and +24 nucleotides downstream of the ribosomal A site respectively. Finally, a stable structural barrier to exoribonuclease activity inhibited A‐site cleavage when introduced immediately downstream of paused ribosomes. These results demonstrate that 3′→5′ exonuclease activity is an important prerequisite for efficient A‐site cleavage. We propose that RNase II degrades mRNA to the downstream border of paused ribosomes, facilitating cleavage of the A‐site codon by an unknown RNase.
Routine colonic biopsies as a new tool to study the enteric nervous system in living patients
Authors: Lebouvier T. , Coron E. , Chaumette T. , Paillusson S. , Des Varannes S. Bruley , Neunlist M. , Derkinderen P.
Published: July 2009

Abstract  Better characterization of enteric neuropathies during the course of gastrointestinal diseases could be of great diagnostic and/or therapeutic interest. However, studies using whole mounts of the enteric nervous system (ENS) are restricted to specific diseases requiring surgery and are also limited by the small number of specimens available. Therefore, we here describe a novel method to obtain whole mounts of submucosal plexus in routine colonic biopsies. We show that a single biopsy displays a substantial number of submucosal ganglia and neurons and that it can be reliably used to perform morphometric and neurochemical analysis and Western Blots quantification of neuronal or glial markers. This method of analysis of the human ENS will enable us to gain better insight into the characterization of enteric neuropathies in living patients.
Timing of maturation and predictors of menarche in girls enrolled in a contemporary British cohort
Authors: Rubin Carol , Maisonet Mildred , Kieszak Stephanie , Monteilh Carolyn , Holmes Adrianne , Flanders Dana , Heron Jon , Golding Jean , McGeehin Mike , Marcus Michele
Published: July 2009

This study describes the timing of puberty in 8‐ to 13‐year‐old girls enrolled in the Avon Longitudinal Study of Parents and Children (ALSPAC) and identifies factors associated with earlier achievement of menarche. Women were enrolled during pregnancy and their offspring were followed prospectively. We analysed self‐reported Tanner staging and menstrual status information collected annually from daughters up to age 13. We used survival models to estimate median age of attainment of stage >1 and stage >2 of breast and pubic hair development and of menarche. We also constructed multivariable logistic regression models to identify factors associated with earlier achievement of menarche.

About 12% of girls reported Tanner breast stage >1 at age 8; 98% of girls were above stage 1 by age 13. For pubic hair, 5% and 95% of girls had attained a stage >1 by 8 and 13 years, respectively. The estimated median age of entry into stage >1 of breast development was 10.14 years (95% confidence interval [CI], 10.08, 10.19), and for pubic hair development the median age was 10.92 years [95% CI, 10.87, 10.97]. One girl (out of 2953) had attained menarche by age 8; 60% had attained menarche by age 13. The estimated median age at menarche was 12.93 years [95% CI, 12.89, 12.98]. Prenatal predictors of menarche by age 11 (12% of girls) included earlier maternal age at menarche, high maternal pre‐pregnancy body mass index, smoking during the third trimester, and non‐white race; the single postnatal predictor was the girl's body size at 8 years. Age at attainment of breast and pubic hair Tanner stage and age at menarche in the ALSPAC cohort are similar to ages reported in other European studies that were conducted during overlapping time periods. The results also give added support to the strong influence of maternal maturation, pre‐adolescent body size and race on the timing of a girl's menarche. This cohort will continue to be followed for maturational information until age 17.
Specificity of anti‐saliva immune response in mice repeatedly bitten by Phlebotomus sergenti
Authors: DRAHOTA J. , LIPOLDOVÁ M. , VOLF P. , ROHOUŠOVÁ I.
Published: July 2009

Sand flies are bloodsucking insects transmitting parasites of genus Leishmania, the causative agents of diseases in humans and dogs. Experimental hosts repeatedly exposed to sand fly saliva can control Leishmania infection. Cell‐mediated anti‐saliva immune response is most likely responsible for this protective effect; however, there is no study so far concerning its antigenic specificity towards different sand fly vectors. In this study, splenocytes from BALB/c mice repeatedly exposed to the bites of Phlebotomus sergenti were challenged ex vivo with salivary gland homogenates from three different sand fly vectors –P. sergenti, P. papatasi, or P. arabicus. Mice bitten by P. sergenti had higher proliferative response to homologous antigen than splenocytes from naive mice. Splenocytes from P. sergenti bitten mice as well as anti‐P. sergenti antibodies partially cross‐reacted with P. papatasi saliva. In contrast, no cross‐reactivity was found with P. arabicus saliva. Our data indicate that both arms of the immune system, cellular and humoral, react in a species‐specific manner. Therefore, the presence of antibodies against salivary components of a certain species indicates the specificity of cell‐mediated immune response as well. The data suggest that unique transmission‐blocking vaccine would be required for each vector –Leishmania combination.
Shellfish allergy in children
Authors: Kandyil Roshni M. , Davis Carla M.
Published: July 2009

Food allergies affect approximately 3.5–4.0% of the world’s population and can range from a mere inconvenience to a life‐threatening condition. Over 90% of food allergies in childhood are caused by eight foods: cow’s milk, hen’s egg, soy, peanuts, tree nuts, wheat, fish, and shellfish. Shellfish allergy is known to be common and persistent in adults, and is an important cause of food induced anaphylaxis around the world for both children and adults. Most shellfish‐allergic children have sensitivity to dust mite and cockroach allergens. Diagnostic cut‐off levels for skin prick testing in children with shrimp allergy exist but there are no diagnostic serum‐specific immunoglobulin E (IgE) values. All patients with symptoms of IgE‐mediated reactions to shellfish should receive epinephrine autoinjectors, even if the initial symptoms are mild. In this study, we review three cases of clinical presentations of shellfish allergy in children.
Clinical and Subclinical Endometritis in the Mare: Both Threats to Fertility
Authors: LeBlanc MM , Causey RC
Published: July 2009

Contents

Endometritis, a major cause of mare infertility arising from failure to remove bacteria, spermatozoa and inflammatory exudate post‐breeding, is often undiagnosed. Defects in genital anatomy, myometrial contractions, lymphatic drainage, mucociliary clearance, cervical function, plus vascular degeneration and inflamm‐ageing underlie susceptibility to endometritis. Diagnosis is made through detecting uterine fluid, vaginitis, vaginal discharge, short inter‐oestrous intervals, inflammatory uterine cytology and positive uterine culture. However, these signs may be absent in subclinical cases. Hypersecretion of an irritating, watery, neutrophilic exudate underlies classic, easy‐to‐detect streptococcal endometritis. In contrast, biofilm production, tenacious exudate and focal infection may characterize subclinical endometritis, commonly caused by Gram‐negative organisms, fungi and staphylococci. Signs of subclinical endometritis include excessive oedema post‐mating and a white line between endometrial folds on ultrasound. In addition, cultures of uterine biopsy tissue or of small volume uterine lavage are twice as sensitive as guarded swabs in detecting Gram‐negative organisms, while uterine cytology is twice as sensitive as culture in detecting endometritis. Uterine biopsy may detect deep inflammatory and degenerative changes, such as disruption of the elastic fibres of uterine vessels (elastosis), while endoscopy reveals focal lesions invisible on ultrasound. Mares with subclinical endometritis require careful monitoring by ultrasound post‐breeding. Treatments that may be added to traditional therapies, such as post‐breeding uterine lavage, oxytocin and intrauterine antibiotics, include lavage 1‐h before mating, carbetocin, cloprostenol, cervical dilators, systemic antibiotics, intrauterine chelators (EDTA–Tris), mucolytics (DMSO, kerosene,N‐acetylcysteine), corticosteroids (prednisolone, dexamethasone) and immunomodulators (cell wall extracts ofMycobacterium phleiandPropionibacterium acnes).