bluuebunny/crossref_metadata_2025 huggingface dataset:
Vector mode based hardware acceleration and emulation for LDPC application
Authors: Liao Y.B. , Han X. , Zhu Z.J. , Wang Y. , Kang S.
Published: March 2013

Purpose

With the rapid development of integrated circuits, verification of SOC chips has become a great challenge due to its integration and complexity. Traditional software‐based simulation methodology cannot meet verification needs. Therefore, FPGA‐based hardware acceleration technologies are requested in SOC verification. The classic methodology of hardware acceleration downloads the DUT (Device under Test) to the FPGA, while part of RTL codes and test bench is still run on the simulator in the workstation. Research found that the speed bottleneck of this methodology is mostly caused by the ping‐pong mode of data transmission between workstation software and the FPGA emulator, thus resulting in that channel transmission time takes too much proportion of total time. The purpose of this paper is to present a vector mode based hardware/software co‐emulation methodology, which leverages a pipeline structure to transmit, receive and buffer data. This methodology reduces the communication overhead by carrying out a parallel mechanism in that while user's design is under test in the emulator, signal data are transmitting in the channel simultaneously, thus increasing the speed of hardware acceleration and emulation.

Design/methodology/approach

The methodology of hardware acceleration proposed by this paper intercepts data for once from the emulation process of a traditional platform as test bench and utilizes direct memory access (DMA) channel to speed up data transfer, as well as increasing reasonable data caching mechanism, which reduces the ratio of channel transmission time in the entire emulation time, achieving accelerating emulation.

Findings

The proposed methodology and traditional hardware acceleration approach were tested on a quasi‐cyclic low‐density parity‐check (LDPC) decoder. Experiment results indicate that the proposed method can increase communication throughput 140 times compared with the traditional approach.

Originality/value

A vector mode based hardware/software co‐emulation methodology is presented in the paper. Higher communication throughput can be achieved by carrying out a parallel mechanism, as well as leveraging a pipeline structure to transmit, receive and buffer data.
Accelerating data distribution in P2P live stream with data reservation mechanism
Authors: Liyong Ren , Ming Lei , Di Zhao
Published: March 2013

Purpose

The purpose of this paper is to improve data transmission efficiency in a P2P system.

Design/methodology/approach

This mechanism does not require changing existing mesh topology, and only necessary peers' evaluation mechanisms need to be introduced.

Findings

This paper presents a data reservation mechanism so that it can transmit data via the push and pull model on the P2P live stream system with the mesh topology. The experiment result of establishing a simulation environment reveals that the above mentioned is an effective way of reducing the data transmission delay by 40 per cent.

Originality/value

To improve data transmission efficiency in a P2P system, this paper presents a data reservation mechanism so that it can transmit data via the push and pull model on the P2P live stream system with the mesh topology.
Scalable group key exchange protocol with provable security
Authors: Li Chengbang , Xu Chunxiang
Published: March 2013

Purpose

The purpose of this paper is to introduce a scalable group key exchange (GKE) protocol with provable security, which is used to establish a confidential channel.

Design/methodology/approach

The protocol in this paper uses line structure, rather than formal ring structure or tree structure, to reduce the amount of calculation and communication.

Findings

In the protocol, every participant just need send two messages. The security can be proved under the Decisional Diffie‐Hellman (DDH) problem.

Originality/value

Using the protocol provides an efficient and secure method to allow group users to share a common key.
Research on resource allocation mechanism for MBMS in wireless cellular system
Authors: Cui Linli , Shao Zhenhai , Zhou Tian , Li Aiyun
Published: March 2013

Purpose

The purpose of this paper is to introduce a resource allocation mechanism for Multimedia Broadcast/Multicast Service (MBMS) in a wireless cellular system and to obtain a rapid and efficient transmission scheme over various types' services. The proposed algorithm is evaluated by simulation results.

Design/methodology/approach

A big problem for wireless communication is the limited time/frequency resources. Therefore, the most important issue is how to utilize these limited resources to transmit various services over a wireless broadband network, especially for MBMS services. In this paper, resource allocation mechanism in a full unicast system is first analyzed with three classical methods, then improved modulation and coding schemes (MCS) methods are proposed in a full multicast system to improve system throughput and spectral efficiency. Based on the foregoing discussions, research on resource allocation mechanism for mixed multicast and unicast traffic is developed in single‐cell and multi‐cell system (MBSFN, MBMS over single frequency network), respectively. Different transmission proportions between multicast and unicast are analyzed and a multiplexing scenario is also considered.

Findings

Resource allocation is a hot topic in wireless communication and there are many investigations on it. However, resource allocation for multicast system, especially for mixed multicast and unicast traffic system, is still a problem worthy of further study. Under same transmission condition in a single cell scenario, system throughput in multicast mode is worse than in unicast mode, which is partly because the number of valid date in multicast resource block (RB) is less than the one in unicast in 3GPP LTE/LTE‐A, on the other hand, because that multicast need to select a relative low MCS to satisfy most MBMS users, even the users with a very poor transmission condition. Fortunately, multicast in MBSFN (MBMS over single frequency network) transfer mode can largely improve system performance.

Originality/value

Improved MCS selection schemes are proposed for full multicast transmission and three transmission scenarios for mixed multicast and unicast traffic are presented to discuss resource allocation mechanism over various types' services. Simulation results show that system performance of multicast system can be greatly enhanced in MBSFN transmission mode, especially with MIMO technology.
The near‐field processing and narrowband imaging algorithm for MIMO array
Authors: Gong Pengcheng , Shao Zhenhai , Zhou Jingquan , Zhu Xueyong
Published: March 2013

Purpose

Imaging is a really difficult problem when systems are implemented in the near‐field region and real‐time needs. The purpose of this paper is to consider a novel system model and present a narrowband 2‐D imaging algorithm in the near‐field region and under the real time constraint.

Design/methodology/approach

The first part of this paper proposes a novel approximation for the round‐trip distance of the near‐field echoed data based on a 2‐D synthetic aperture planar array. The second part of this work proposes a near‐field narrow imaging algorithm based on the above system model. Narrowband waveforms are employed in the array system, so that the range alignment and decoupling in range‐azimuth are not necessary.

Findings

The errors of the proposed approximation are much smaller as compared with those of the Fresnel approximation. For example, the errors of the proposed approximation are negligible when the antenna is fixed at (0, 0). In other cases, the errors are decreased by almost 50 percent. Compared with 2‐D plane array, the synthetic aperture plane of the paper reduces the number of antennas. Finally, numerical simulation results verify the validity of the imaging algorithm.

Originality/value

The near‐field difficulty is solved by the adoption of the proposed approximation. The theoretical analysis and simulation results verify the validity of the imaging algorithm in the near‐field region and under the real time constraint.
A measurement of real travel speed for road segment with magnetic sensors
Authors: Zhang Enzhan , Kuang Yujun
Published: March 2013

Purpose

The purpose of this paper is to introduce a weighted average method to process speed measurements from multiple magnetic sensors, which are installed on road segments. Speeds are weighted‐averaged in a fix duration time (5 minutes) for each sensor across location index of the sensor where it was installed. The proposed method is evaluated with numeric and simulation results.

Design/methodology/approach

Unlike traditional vehicle average speed measurements, the authors propose a weighted‐average speed measurement method of road segment, using wireless magnetic sensor nodes, which are installed on the measured road segment. Magnetic sensors offer a non‐contact vehicle detection method, and small sensors with relatively low power consumption. Using magnetic sensors, the local changes in the Earth's magnetic field caused by the presence of a moving vehicle can be measured and the vehicle's speed obtained. Next, using adaptive weighted average algorithm and space weighted algorithm in a fixed period, the weighted average travel speed of road segment can be obtained.

Findings

In current literature, there are many methods to measure vehicles' speed on road, such as image‐based, radar‐based, GPS‐based, double‐loop‐based or magnetic sensor‐based, but most of them only provide individual vehicle speed. Using probe vehicles, mean travel speed of road segment can be obtained, but it is costly on hardware and measurement, because many probe‐vehicles need to be used on roads and many measurements need to be done everyday. GPS data can be used to provide valuable travel speed data for Intelligent Transportation System (ITS). However, not every vehicle is equipped with GPS and to access ID numbers for personal cars would entail privacy problems. Mean travel speed of road segment is obtained based on statistical average speed. Generally, statistical average speed is used, which is based upon Gaussian distribution is not true in traffic systems.

Originality/value

By using wireless magnetic sensor nodes, vehicle instantaneous speeds are obtained in a fixed time when vehicles are passing over sensor nodes and then the adaptive weighted average speed on each sensor node location is computed based on the monitoring data from each sensor node in the fixed time. Considering different weights of each lane and road space (in the middle of the road segment or near the intersection), the proposed scheme can obtain the weighted‐average speed of the road segment.
Beyond price: how does trust encourage online group's buying intention?
Authors: Ku Edward C.S.
Published: March 2013

Purpose

The purpose of this paper is to investigate how online trust affects group shopping intention in the Ihergo web site.

Design/methodology/approach

Samples from the Ihergo web site were collected by mailing a questionnaire survey to those who agreed to participate.

Findings

Group‐buying operators need to understand their consumers and the scheduling shopping rules between internet shoppers and firms. Moreover, word‐of‐mouth (WOM) can be created online by offering web visitors the ability to access the opinions of satisfied customers.

Practical implications

An online business may adopt different methods to enhance its customer satisfaction level. When people enter a significant amount of personal data at a web site, they are typically reluctant to change vendors and enter the data again.

Social implications

Customers view a group‐buying operator as a shopping expert, and expect that the group‐buying operator can handle shopping problems before a dispute occurs.

Originality/value

The findings of this study provide interesting insights for group‐buying operators interested in group‐buying commerce; consumers having a high level of interest in shopping possess a strong motivation and desire to interact with the group‐buying operator.
Public contributions to private‐collective systems: the case of social bookmarking
Authors: Benbunan‐Fich Raquel , Koufaris Marios
Published: March 2013

Purpose

The aim of this study is to provide a theoretical extension to the private‐collective model of information sharing along with an empirical test with users of a social bookmarking website.

Design/methodology/approach

The paper includes a survey of 112 users of an actual bookmarking site recruited through an online research panel firm. The survey consisted of scales adapted from the literature as well as scales developed by the authors.

Findings

The results indicate that contributions to a social bookmarking site are a combination of intentional and unintentional contributions. A significant predictor of intentional public contributions of bookmarks is an egoistic motivation to see one as competent by contributing valuable information. However, there is also a significant but negative relationship between altruism and public contribution whereby users concerned with the needs of others limit their public contributions.

Research limitations/implications

The sample consists of users of a particular social bookmarking site (Yahoo!'s MyWeb). Therefore, the results may not be generalizable to other social bookmarking websites, different types of social networks, or other contexts lacking the public/private option for contributions. Second, since the data comes from a cross‐sectional survey, as opposed to a longitudinal study, the causal relations posited in the model and substantiated with the statistical analyses can only be inferred based on the authors’ theoretical development. Third, although the size of the sample (112 respondents) is appropriate for PLS analysis it may have been insufficient to detect other significant relationships.

Practical implications

Administrators of social bookmarking sites should incorporate incentive and feedback mechanisms to inform contributors whether they contributions have been used (for example, with times viewed) and/or deemed useful (with numeric or qualitative ratings).

Social implications

The results suggest that both selfish motivations associated with the need to feel competent (egoism), as well as selfless concerns for the needs of other users (altruism) drive intentional contributions to the public repository in social bookmarking systems. These two counterbalancing forces indicate that a mix of egoism and altruism is crucial for the long‐term sustainability of social web sites based on information sharing.

Originality/value

This study provides theoretical explanations and empirical evidence of egoism and altruism as significant explanations for cooperation in private‐collective models, such as the ones represented by social bookmarking systems.
Urban and rural differences
Authors: Hsieh Tsui‐Chuan , Yang Keng‐Chieh , Yang Conna , Yang Chyan
Published: March 2013

Purpose

The purpose of this article is to investigate urban and rural differences for online activities and e‐payment behavior patterns.

Design/methodology/approach

This study applied the MLCA model to investigate Internet usage patterns from 11 online applications among 10,909 Taiwan residents in 25 different regions.

Findings

The results showed that online behavior patterns exhibited regional differences, as the regional segments affected the individual segments of different use patterns. For instance, the urban area comprised a higher proportion of members who were accustomed to internet applications and skilled in online shopping by using a credit card. The rural area made up a higher proportion of members who only occasionally used online services. Moreover, rural region residents used other payment methods (excluding credit cards) more often than urban region residents. As expected, users’ personal characteristics also dictated the online behavior pattern. For instance, people with higher‐level income spent relatively more money for online shopping and often used various internet applications than others.

Practical implications

The findings herein should help Internet service providers form an applicable guideline for developing service strategies of higher service satisfaction regarding products and users’ needs.

Originality/value

This study implemented a multilevel latent class model to investigate online behavior patterns that exhibited urban and rural differences, with the goal of providing service providers an understanding and mastery of their target users.
Modeling utilitarian‐hedonic dual mediation (UHDM) in the purchase and use of games
Authors: Davis Robert , Lang Bodo , Gautam Neil
Published: March 2013

Purpose

It is assumed that consumers consume games to experience hedonic and utilitarian value. However, there is no conceptual model or empirical evidence that supports this hypothesis in the game context or clarifies whether these consumption values have dual mediated or individual effects. Therefore, the purpose of this research is to model the relationship between hedonic and utilitarian consumption and game purchase and usage.

Design/methodology/approach

This research question is answered through two studies. In Study One, qualitative interviews with 18 gamers were implemented to explore the relationship between hedonic and utilitarian consumption and, game purchase and usage behaviour. In Study Two, we surveyed 493 consumers and conducted confirmatory factor analysis and structural equation modelling across four game types to model this relationship.

Findings

The paper concludes that hedonic rather than utilitarian consumption positively impacts purchase and usage. Support was also found for the utilitarian‐hedonic dual mediation model (UHDM). Therefore, utilitarian consumption has an indirect causal effect on game purchase or usage through hedonic consumption.

Practical implications

Game development for consumers online, on wireless devices and on consoles should place greater emphasis on the practical implications of hedonic consumption. Attention could be focused on perceived enjoyment, self‐concept, self‐congruity and self‐efficacy as the primary drivers of use and purchase. Practical solutions should also be developed to develop the UHDM effect.

Originality/value

This is the first paper in the game context to explore and model the relationship between hedonic, utilitarian consumption and the UHDM effect on game purchase and usage. This paper is also unique because it provides results across four game groups: all games (ALL), Sports/Simulation/Driving (SSD), Role Playing Game/Massively Multiplayer Online Role‐Playing Game Strategy (RPG), and Action/Adventure/Fighting (AAF).
Leadership, clinician managers and a thing called “hybridity”
Authors: Fulop Liz
Published: March 2013

Purpose

In many countries leadership theories and leadership development programs in healthcare have been dominated by individualistic and heroic approaches that focus on developing the skills and competencies of health professionals. Alternative approaches have been proffered but mainly in the form of post‐heroic and distributed forms of leadership. The notion of “hybridity” has emerged to challenge the assumptions of distributed leadership. The paper seeks to explore how the concept of hybridity can be used to re‐theorize leadership in healthcare as it relates to clinician managers (or hybrid‐professional managers).

Design/methodology/approach

The theoretical developments are explored and empirical material is presented from research in Australian public hospitals to support the case for the existence of hybridized forms of leadership in healthcare. The paper discusses whether hybridity needs re‐theorizing to adequately account for clinician leadership. It contributes to debates surrounding the role of clinician leadership in healthcare reform particularly in relation to those doctors who occupy management positions at the division or unit levels as distinct to CEOs. The study uses qualitative research, i.e. interactive interviews to present accounts of how healthcare professionals describe leadership. It undertakes both deductive and inductive theme analysis of the interview material.

Findings

There is support for hybridized configurations of leadership in interview materials of healthcare professionals but other aspects were also noted that cannot be explained by this approach alone.

Originality/value

The paper is the first to examine the concept of hybridity in the context of clinician leadership. Many approaches to leadership in healthcare fail to address the complexity of leadership within the ranks of clinician managers and thus are unable to deal adequately with the role of leadership in healthcare reform and change.
Sensemaking: a driving force behind the integration of professional practices
Authors: Sylvain Chantal , Lamothe Lise
Published: March 2013

Purpose

There has been considerable effort in recent years to link and integrate professional services more closely for patients with comorbidities. However, difficulties persist, especially at the clinical level. This study aims to shed light on these difficulties by examining the process of sensemaking in professionals directly involved in this integration.

Design/methodology/approach

The authors conducted an eight‐year longitudinal case study of an organization specializing in mental health and substance abuse. Different data collection methods were used, including 34 interviews conducted between 2003 and 2009, observations and document analysis. The authors performed a qualitative analysis of the data using a processual perspective.

Findings

This paper provides empirical insights about the nature of the sensemaking process in which professionals collectively participate and the effects of this process on the evolution of integrated services. It suggests that the development of integrated practices results from an evolutional and collective process of constructing meanings that is rooted in the work activities of the professionals involved.

Practical implications

By drawing attention to the capacity of professionals to shape the projects they are implementing, this study questions the capacity of managers to actually manage such a process. In order to obtain the expected benefits of integration projects, such emergent dynamics must first be recognized and then supported. Only then can thought be given to mastering them.

Research limitations/implications

The fact that this is a single case study is not a limitation per se, although it does raise the issue of the transferability of results. Replicating the study in other contexts would verify the applicability of the authors' conclusions.

Originality/value

This study offers a fresh perspective on the difficulties generally encountered at the clinical level when trying to integrate services. It makes a significant contribution to work on the dynamics of sensemaking in organizational life.
Schools' absorptive capacity to innovate in health promotion
Authors: Deschesnes Marthe , Drouin Nathalie , Couturier Yves
Published: March 2013

Purpose

A comprehensive “health promoting schools” (HPS) approach is advocated by the World Health Organization to foster the health of students. To date, few studies have evaluated schools' capacity to implement it in an optimal way. The purpose of this paper is to present a conceptual framework that identifies core features likely to facilitate the incorporation of innovation, such as HPS, into school functioning.

Design/methodology/approach

The framework was built by combining dimensions derived from two major strands of literature, i.e. management and HPS. It has taken root in Zahra and George's model of organisation absorptive capacity (AC) for new knowledge but has been adapted to better explore AC in a school context. The contrasting cases of two secondary schools that adopted a HPS approach in Quebec, Canada, for at least three years were used to illustrate the value of the framework.

Findings

The framework proposed is a multidimensional model that considers components such as modulators, antecedents, integration mechanisms and strategic levers as potential determinants of AC, i.e. acquisition, assimilation, transformation and exploitation. The conceptual framework helped to qualify and compare AC regarding HPS in the two cases and holds promise to appreciate mechanisms having the greatest influence on it.

Originality/value

The framework can serve as a conceptual guide to facilitate the absorption of innovation in schools and to design future empirical research to better understand the underlying process by which schools strengthen their capacities to become settings conducive to the health of youth.
Healthcare performance turned into decision support
Authors: Michel Sørup Christian , Jacobsen Peter
Published: March 2013

Purpose

The purpose of this study is to first create an overview of relevant factors directly influencing employee absence in the healthcare sector. The overview is used to further investigate the factors identified using employee satisfaction survey scores exclusively. The result of the overall objective is a management framework that allows managers to gain insight into the current status of risk factors with high influence on employee absence levels.

Design/methodology/approach

The research consists of a quantitative literature study supported by formal and semi‐formal interviews conducted at the case organisations. Employee satisfaction surveys were applied to analyse the development over time of selected factors correlated with concurrent employee absence rates. Checking for causal results, comparisons with the included published literature findings were also carried out.

Findings

Four major clustered factors, three of which constitute the term “social capital”, showed a high degree of connection with employee absence rates. The factors are general satisfaction, fairness, reliance and co‐operation. Integrating the four elements in a management framework will provide valuable and holistic information about the determinants with regard to current levels of employee absence. The framework will be a valuable support for leaders with the authority to alter the determinants of employee absence.

Research limitations/implications

Since a great part of the empirical material is supplied from the healthcare sector, the results obtained could be restricted to this sector. Inclusion of data from Arbejdsmarkedets Tillægspension (ATP) showed no deviation from the results in the healthcare sector.

Practical implications

The product of the study is a decision support tool for leaders to cope with levels of employee absence. The framework is holistic and can prove to be a valuable tool to take a bearing of where to focus future initiatives.

Originality/value

Gathering former observational studies in a complete overview embracing many relevant factors that influence sickness absence has not yet been attempted. Hospital management is provided with valuable information when given insight into the factors that control employee absence behaviour. Having this insight will enable the managers to promote a healthy working environment, thus lowering employee absence rates to a minimum.
Ends Changed, Means Retained: Scholarship Programs, Political Influence, and Drifting Goals
Authors: Wilson Iain
Published: March 2013

Research Highlights and Abstract

Governments offer scholarships to foreign nationals expected to become influential in their home countries and shape public opinion to the benefit of their sponsor. This is known as the ‘opinion leader’ model. The histories of three British scholarship programs whose directors now subscribe to the ‘opinion leader’ model suggest they were actually set up for other reasons. Beliefs about what the programs are for have shifted toward the ‘opinion leader’ model even as they have continued to do the same things. The pattern of changing objectives seems to fit a Kingdonian model of the policy process.

Many governments offer scholarships specifically to foreign citizens. In recent years both policymakers and academics have associated these scholarships with political influence, arguing that they generate sympathetic and influential alumni who support positive relationships between their home country and their sponsor. Digging deeper into the histories of several scholarship programs which are now being portrayed in this way shows they were actually set up for very different reasons. Explanations for why scholarships are being given to foreign citizens have changed over time, consistent with a Kingdonian model of the policy process. We need to be cautious about taking these claims at face value, an important reminder for foreign policy analysts more generally.
Magnesium sulphate for prevention of eclampsia: are intramuscular and intravenous regimens equivalent? A population pharmacokinetic study
Authors: Salinger DH , Mundle S , Regi A , Bracken H , Winikoff B , Vicini P , Easterling T
Published: March 2013

Objective

To compare magnesium sulphate concentrations achieved by intramuscular and intravenous regimens used for the prevention of eclampsia.

Setting

Low‐resource obstetric hospitals in Nagpur and Vellore, India.

Population

Pregnant women at risk for eclampsia due to hypertensive disease.

Methods

A pharmacokinetic study was performed as part of a randomised trial that enrolled 300 women comparing intramuscular and intravenous maintenance regimens of magnesium dosing. Data from 258 enrolled women were analysed in the pharmacokinetic study. A single sample was drawn per woman with the expectation of using samples in a pooled data analysis.

Main outcome measures

Pharmacokinetic parameters of magnesium distribution and clearance.

Results

Magnesium clearance was estimated to be 48.1 dl/hour, volume of distribution to be 156 dl and intramuscular bioavailability to be 86.2%. The intramuscular regimen produced higher initial serum concentrations, consistent with a substantially larger loading dose. At steady state, magnesium concentrations in the intramuscular and intravenous groups were comparable. With either regimen, a substantial number of women would be expected to have serum concentrations lower than those generally held to be therapeutic.

Conclusions

Clinical implications were that a larger loading dose for the intravenous regimen should be considered; where feasible, individualised dosing of magnesium sulphate would reduce the variability in serum concentrations and might result in more women with clinically effective magnesium concentrations; and lower dose magnesium suphate regimens should be considered with caution.
Microbiota and healthy ageing: observational and nutritional intervention studies
Authors: Brüssow Harald
Published: March 2013

Hundred years ago Metchnikoff associated human health and particularly healthy ageing with a specific type of gut microbiota. Classical culture methods associated a decrease in bifidobacteria and an increase in enterobacteria with ageing. Modern molecular methods blurred this simple picture and documented a substantial inter‐individual variability for the gut microbiome even when stratifying the elderly subjects according to health status. Nutritional interventions with resistant starch showed consistent gut microbiota changes across studies from different geographical areas and prebiotic supplementation induced a 10‐fold increase in gut bifidobacteria. However, in the ELDERMET study, microbiota changes do not precede, but follow the changes in health status of elderly subjects possibly as a consequence of diet changes.
Detection of multiple species of human Paragonimus from Mexico using morphological data and molecular barcodes
Authors: López‐Caballero J. , Oceguera‐Figueroa A. , León‐Règagnon V.
Published: March 2013

Paragonimus mexicanus is the causal agent of human paragonimiasis in several countries of the Americas. It is considered to be the only species of the genus present in Mexico, where it is responsible for human infection. Through the investigation of P. mexicanus specimens from several places throughout Mexico, we provide morphological, molecular and geographical evidence that strongly suggests the presence of at least three species from this genus in Mexico. These results raise questions regarding the diagnosis, treatment, prophylaxis and control of human paragonimiasis in Mexico. We also provide a brief discussion regarding biodiversity inventories and the convenience of providing molecular and morphological information in biodiversity studies.
Indexing butterfly abundance whilst accounting for missing counts and variability in seasonal pattern
Authors: Dennis Emily B. , Freeman Stephen N. , Brereton Tom , Roy David B.
Published: March 2013

Volunteer‐based ‘citizen science’ schemes now play a valuable role in deriving biodiversity indicators, both aiding the development of conservation policies and measuring the success of management. We provide a new method for analysing such data based on counts of invertebrate species characterised by highly variable numbers within a season combined with a substantial proportion of proposed survey visits not made.

Using the UK Butterfly Monitoring Scheme (UKBMS) for illustration, we propose a two‐stage model that makes more efficient use of the data than previous analyses, whilst accounting for missing values. Firstly, generalised additive models were applied separately to data from each year to estimate the annual seasonal flight patterns. The estimated daily values were then normalised to estimate a seasonal pattern that is the same across sites but differs between years. A model was then fitted to the full set of annual counts, with seasonal values as an offset, to estimate annual changes in abundance accounting for the varying seasonality.

The method was tested and compared against the current approach and a simple linear interpolation using simulated data, parameterised with values estimated from UKBMS data for three example species. The simulation study demonstrated accurate estimation of linear time trends and improved power for detecting trends compared with the current model.

Comparison of indices for species covered by the UKBMS under the various model approaches showed similar predicted trends over time, but confidence intervals were generally narrower for the two‐stage model.

In addition to creating more robust trend estimates, the new method allows all volunteer records to contribute to the indices and thus incorporates data from more populations within the geographical range of a species. On average, the current model only enables data from 60% of 10 km2 grid squares with monitored sites to be included, whereas the two‐stage model uses all available data and hence provides full coverage at least of the monitored area. As many invertebrate species exhibit similar patterns of emergence or voltinism, our two‐stage method could be applied to other taxa.
Can Carbon Monoxide Prevent Infection‐Mediated Preterm Birth in a Mouse Model?
Authors: Peltier Morgan R. , Koo Hschi‐Chi , Gurzenda Ellen M. , Arita Yuko , Klimova Natalia G. , Olgun Niccole , Hanna Nazeeh
Published: March 2013

Problem

Preterm birth is frequently caused by intrauterine infection and inflammation. Recent studies have demonstrated that carbon monoxide (CO), which is produced endogenously, has potent anti‐inflammatory properties. Whether or not CO can prevent infection‐mediated preterm birth is unknown.

Methods

Mice were assigned to one of four groups: sham infection, sham infection + CO, infection, or infection + CO. Infections were established by intra‐uterine injection of Escherichia coli on day 14 of pregnancy. Animals received daily i.p. injections of 1 mL CO‐saturated lactated ringers solution (LRS) or LRS alone beginning on the morning of surgery. Gestational age at delivery and litter characteristics was noted. In second experiment, animals were sacrificed 24 hrs post‐surgery and tissues were harvested for cytokine analyses.

Results

Escherichia coli intrauterine infection increased the number of animals delivering preterm. This effect was significantly ameliorated by CO‐LRS. CO‐treatment also increased litter size and weights of the surviving offspring. Cytokines in the amniotic fluid and the placenta were increased by E. coli exposure, but CO had no detectible effect on E. coli‐stimulated cytokine production. No effects of CO were detected in sham‐infected animals.

Conclusion

Supplemental CO improves pregnancy outcome after intrauterine infection and may function at a point downstream of, or through pathways independent of, induction of proinflammatory cytokines.
Tacrolimus placental transfer at delivery and neonatal exposure through breast milk
Authors: Zheng Songmao , Easterling Thomas R. , Hays Karen , Umans Jason G. , Miodovnik Menachem , Clark Shannon , Calamia Justina C. , Thummel Kenneth E. , Shen Danny D. , Davis Connie L. , Hebert Mary F.
Published: March 2013

Aim(s)

The current investigation aims to provide new insights into fetal exposure to tacrolimus in utero by evaluating maternal and umbilical cord blood (venous and arterial), plasma and unbound concentrations at delivery. This study also presents a case report of tacrolimus excretion via breast milk.

Methods

Maternal and umbilical cord (venous and arterial) samples were obtained at delivery from eight solid organ allograft recipients to measure tacrolimus and metabolite bound and unbound concentrations in blood and plasma. Tacrolimus pharmacokinetics in breast milk were assessed in one subject.

Results

Mean (±SD) tacrolimus concentrations at the time of delivery in umbilical cord venous blood (6.6 ± 1.8 ng ml−1) were 71 ± 18% (range 45–99%) of maternal concentrations (9.0 ± 3.4 ng ml−1). The mean umbilical cord venous plasma (0.09 ± 0.04 ng ml−1) and unbound drug concentrations (0.003 ± 0.001 ng ml−1) were approximately one fifth of the respective maternal concentrations. Arterial umbilical cord blood concentrations of tacrolimus were 100 ± 12% of umbilical venous concentrations. In addition, infant exposure to tacrolimus through the breast milk was less than 0.3% of the mother's weight‐adjusted dose.

Conclusions

Differences between maternal and umbilical cord tacrolimus concentrations may be explained in part by placental P‐gp function, greater red blood cell partitioning and higher haematocrit levels in venous cord blood. The neonatal drug exposure to tacrolimus via breast milk is very low and likely does not represent a health risk to the breastfeeding infant.
Thrombotic risk in patients with immune thrombocytopenia and its association with antiphospholipid antibodies
Authors: Kim Ki‐Jo , Baek In‐Woon , Yoon Chong‐Hyeon , Kim Wan‐Uk , Cho Chul‐Soo
Published: March 2013

Patients with immune thrombocytopenia (ITP) paradoxically have an increased risk of thrombosis. The presence of antiphospholipid antibodies (aPL) has been observed in a substantial proportion of ITP patients, but its clinical significance remains to be established. This study retrospectively investigated the prevalence and clinical significance of aPL in ITP patients and assessed the risk factors for thrombosis. One hundred and sixty‐five subjects with ITP were included in the study and followed for a mean period of 63·4 months. Sixty‐nine (41·6%) patients were positive for aPL at diagnosis, and their clinical characteristics and course of ITP were not different from those of aPL‐negative patients. Twenty‐one (12·7%) patients developed a thrombotic event during follow‐up and the cumulative incidence rate ratio of aPL‐positive to aPL‐negative patients for thromboembolism was 3·15 [95% confidence interval (CI) 1·21–8·17] after adjusting for confounding factors. Lupus anticoagulant and hypertension were identified by Cox regression analysis as independent risk factors for thrombosis [hazard ratio (HR) 4·1, 95% CI 1·4–11·9, P = 0·009 and HR 5·6, 95% CI 1·9–15·8, P = 0·001, respectively]. Our results showed that a substantial proportion of ITP patients were aPL‐positive, and that lupus anticoagulant and hypertension were independent risk factors for thrombosis. Detection of aPL can provide useful information for identifying patients at high‐risk for developing thrombosis.
A novel synthetic lipopeptide is allergy‐protective by the induction of LPS‐tolerance
Authors: Stiehm M. , Peters K. , Wiesmüller K.‐H. , Bufe A. , Peters M.
Published: March 2013

Background

Exposure to the environment of traditional farms can protect children from some allergic disease. Due to this exposure, TLR2 expression in these children is increased. TLR2 ligands derived from gram‐positive bacteria are found in the dust of these farms.

Objectives

We proved whether a synthetic lipopeptide binding to the TLR1/2 heterodimer is able to protect from allergic disease in two different murine models of allergy. We also investigated the immunological mechanisms underlying the protective properties of the lipopeptide.

Methods

We synthesized a lipopeptide derived from a germination lipoprotein of Bacillus cereus (LPGerD). We evaluated the immunomodulatory activity of LPGerD in a murine model of systemic sensitization (OVA/Alum) and in a model in which mice were sensitized with OVA pulsed bone‐marrow‐derived dendritic cells (BMDCs) via the airways. Furthermore, the induction of LPS tolerance was studied.

Results

Treatment of mice with LPGerD in a mouse model of asthma led to protection against sensitization and airway inflammation. Similarly, bone‐marrow‐derived dendritic cells (BMDCs) pre‐treated with LPGerD were not able to prime mice for allergic immune response. We observed that pre‐treatment with LPGerD led to the induction of a LPS‐tolerant state in BMDCs. These cells secreted markedly lower amounts of pro‐inflammatory cytokines upon LPS stimulation. Furthermore, we observed an up‐regulation of IRAK‐M mRNA in BMDCs pre‐treated with LPGerD.

Conclusions and Clinical Relevance

Our results suggest that induction of a LPS‐tolerant state in antigen‐presenting cells (APCs) may contribute to the protective effect of a farming environment. TLR2 agonists similar to those appearing in cowshed dust extracts, such as our synthetic LPGerD, lead to the ignorance of the LPS stimulus, which is important for the activation of APCs to mount a Th2 immune response. This substance might be a promising candidate for allergy‐preventive treatments as LPGerD had only low pro‐inflammatory characteristics.
Identification of enolases and aldolases as important fish allergens in cod, salmon and tuna: component resolved diagnosis using parvalbumin and the new allergens
Authors: Kuehn A. , Hilger C. , Lehners‐Weber C. , Codreanu‐Morel F. , Morisset M. , Metz‐Favre C. , Pauli G. , de Blay F. , Revets D. , Muller C. P. , Vogel L. , Vieths S. , Hentges F.
Published: March 2013

Background

The majority of fish‐allergic patients are sensitized to parvalbumin, known to be the cause of important IgE cross‐reactivity among fish species. Little is known about the importance of fish allergens other than parvalbumin.

Objective

The aim of this study was to characterize hitherto undefined fish allergens in three commonly consumed fish species, cod, salmon and tuna, and to evaluate their importance for in vitro IgE‐diagnosis in addition to parvalbumin and fish gelatin.

Methods

Sixty‐two patients were diagnosed by clinical history, skin prick tests and specific IgE to fish extracts. Two new fish allergens from cod, salmon and tuna were identified by microsequencing. These proteins were characterized by immunoblot, ELISA and mediator release assay. Purified parvalbumin, enolase, aldolase and fish gelatin were used for quantification of specific IgE in ELISA.

Results

Parvalbumin and two other allergens of 50 and 40 kDa were detected in IgE‐immunoblots of cod, salmon and tuna extracts by most patient sera. The 50 and 40 kDa proteins were identified as beta‐enolase and fructose‐bisphosphate aldolase A respectively. Both purified enzymes showed allergenic activity in the mediator release assay. Indeed, 72.6% of the patients were sensitized to parvalbumin, 20% of these had specific IgE to salmon parvalbumin only. IgE to enolases were found in 62.9% (0.5–95.0 kUA/L), to aldolases in 50.0% (0.4‐26.0 kUA/L) and to fish gelatin in 19.3% (0.4–20.0 kUA/L) of the patients. Inter‐species cross‐reactivity, even though limited, was found for enolases and aldolases by IgE‐inhibition ELISA.

Conclusions and Clinical Relevance

Fish enolase and aldolase have been identified as important new fish allergens. In fish allergy diagnosis, IgE to enolase and aldolase are especially relevant when IgE to parvalbumin are absent.
Fungal rhinosinusitis: what every allergist should know
Authors: Callejas C. A. , Douglas R. G.
Published: March 2013

The interaction between fungi and the sinonasal tract results in a diverse range of diseases with an equally broad spectrum of clinical severity. The classification of these interactions has become complex, and this review seeks to rationalize and simplify the approach to fungal diseases of the nose and paranasal sinuses. These conditions may be discussed under two major headings: non‐invasive disease (localized fungal colonization, fungal ball and allergic fungal rhinosinusitis) and invasive disease (acute invasive rhinosinusitis, chronic invasive rhinosinusitis and granulomatous invasive rhinosinusitis). A diagnosis of fungal rhinosinusitis is established by combining findings on history, clinical examination, laboratory testing, imaging and histopathology. The immunocompetence of the patient is of great importance, as invasive fungal rhinosinusitis is uncommon in immunocompetent patients. With the exception of localized fungal colonization, treatment of all forms of fungal rhinosinusitis relies heavily on surgery. Systemic antifungal agents are a fundamental component in the treatment of invasive forms, but are not indicated for the treatment of the non‐invasive forms. Antifungal drugs may have a role as adjuvant therapy in allergic fungal rhinosinusitis, but evidence is poor to support recommendations. Randomized controlled trials need to be performed to confirm the benefit of immunotherapy in the treatment of allergic fungal rhinosinusitis. In this article, we will summarize the current literature, addressing the controversies regarding the diagnosis and management of fungal rhinosinusitis, and focussing on those aspects which are important for clinical immunologists and allergists.
Identification of a founder EPCAM deletion in Spanish Lynch syndrome families
Authors: Mur P. , Pineda M. , Romero A. , del Valle J. , Borràs E. , Canal A. , Navarro M. , Brunet J. , Rueda D. , Ramón y Cajal T. , Lázaro C. , Caldés T. , Blanco I. , Soto J.L. , Capellá G.
Published: March 2013

Germline deletions at the 3′‐end of EPCAM have been involved in the etiology of Lynch syndrome (LS). The aim of this study was to characterize at the molecular level Spanish families harboring EPCAM deletions. Non‐commercial multiplex ligation‐dependent probe amplification (MLPA) probes and long‐range polymerase chain reaction (PCR) amplification were used to characterize each deletion. Haplotyping was performed by analyzing eight microsatellite markers and five MSH2single nucleotide polymorphisms (SNPs). Methylation of MSH2 was analyzed by methylation specific‐MLPA. Tumors diagnosed in seven Spanish families harboring EPCAM deletions were almost exclusively colorectal. Mosaicism in MSH2 methylation was observed in EPCAM deletion carrier samples, being average methylation levels higher in normal colon and colorectal tumors (27.6% and 31.1%), than in lymphocytes and oral mucosa (1.1% and 0.7%). Three families shared the deletion c.858 + 2568_*4596del, with a common haplotype comprising 9.9 Mb. In two families the novel EPCAM deletion c.858 + 2488_*7469del was identified. This study provides knowledge on the clinical and molecular characteristics of mosaic MSH2 epimutations. The identification of an EPCAM founder mutation has useful implications for the molecular diagnosis of LS in Spain.