bluuebunny/crossref_metadata_2025 huggingface dataset:
Thermal effects in the Input Optics of the Enhanced Laser Interferometer Gravitational-Wave Observatory interferometers
Authors: Dooley Katherine L. , Arain Muzammil A. , Feldbaum David , Frolov Valery V. , Heintze Matthew , Hoak Daniel , Khazanov Efim A. , Lucianetti Antonio , Martin Rodica M. , Mueller Guido , Palashov Oleg , Quetschke Volker , Reitze David H. , Savage R. L. , Tanner D. B. , Williams Luke F. , Wu Wan
Published: March 2012

We present the design and performance of the LIGO Input Optics subsystem as implemented for the sixth science run of the LIGO interferometers. The Initial LIGO Input Optics experienced thermal side effects when operating with 7 W input power. We designed, built, and implemented improved versions of the Input Optics for Enhanced LIGO, an incremental upgrade to the Initial LIGO interferometers, designed to run with 30 W input power. At four times the power of Initial LIGO, the Enhanced LIGO Input Optics demonstrated improved performance including better optical isolation, less thermal drift, minimal thermal lensing, and higher optical efficiency. The success of the Input Optics design fosters confidence for its ability to perform well in Advanced LIGO.
The mechanism of emerging catalytic activity of gold nano-clusters on rutile TiO2(110) in CO oxidation reaction
Authors: Mitsuhara K. , Tagami M. , Matsuda T. , Visikovskiy A. , Takizawa M. , Kido Y.
Published: March 2012

This paper reveals the fact that the O adatoms (Oad) adsorbed on the 5-fold Ti rows of rutile TiO2(110) react with CO to form CO2 at room temperature and the oxidation reaction is pronouncedly enhanced by Au nano-clusters deposited on the above O-rich TiO2(110) surfaces. The optimum activity is obtained for 2D clusters with a lateral size of ∼1.5 nm and two-atomic layer height corresponding to ∼50 Au atoms/cluster. This strong activity emerging is attributed to an electronic charge transfer from Au clusters to O-rich TiO2(110) supports observed clearly by work function measurement, which results in an interface dipole. The interface dipoles lower the potential barrier for dissociative O2 adsorption on the surface and also enhance the reaction of CO with the Oad atoms to form CO2 owing to the electric field of the interface dipoles, which generate an attractive force upon polar CO molecules and thus prolong the duration time on the Au nano-clusters. This electric field is screened by the valence electrons of Au clusters except near the perimeter interfaces, thereby the activity is diminished for three-dimensional clusters with a larger size.
Occupational Medicine for the GP
Authors: Ashdown Daniel , Lashbrooke Ben
Published: March 2012

Occupational medicine is concerned with the relationship between work and health and covers a wide variety of disciplines. Following the 2008 Black and 2010 Marmot reviews, in which the costs and damaging effects of worklessness were highlighted, occupational medicine has never been more important. Health and Safety Executive figures for 2010/2011 show that 26.4 million working days were lost due to work-related ill health and injury and it is estimated that the cost of work-related ill health is approaching £100 billion/year. In the UK, dedicated occupational medicine teaching in medical schools is given a low priority despite the fact that doctors are expected to assess fitness to work, advise patients about returning to work and, according to the General Medical Council's ‘Tomorrow's Doctors’, understand the link between health and work. This article discusses how and why patients present with problems related to their work and highlights key areas where an appreciation of occupationally related disease is important for the GP.
Dietary intakes and anthropometric indices of 337 adults from Cyprus
Authors: Andreou Eleni , Philippou Christiana , Papandreou Dimitrios
Published: March 2012

Purpose

There is increasing evidence that diets high in energy, saturated fatty acids, cholesterol and low in fiber and antioxidants may lead to cardiovascular disease, hypertension and cancer. The purpose of this paper is to investigate, for the first time, the anthropometric measurements and dietary intakes of a randomly selected and representative sample of men and women from Cyprus and compare them with the recent recommended dietary guidelines for adults.

Design/methodology/approach

A sample of 337 individuals was selected using the method of stratified random sampling, with proportional percentage of women (51.5 per cent) and men (48.5 per cent). Anthropometric and dietary characteristics were recorded for all subjects.

Findings

Males were found to have significantly (p<0.001) higher levels of weight, systolic blood pressure, diastolic blood pressure, waist circumference, basal metabolic rate, as well as lean body mass and lower body fat levels, compared to females. Both genders were found to have significantly lower intakes of vitamin A, B6, calcium and magnesium and significantly higher amounts of vitamin C, B1, B2, and iron (p<0.001) compared to DRIs, respectively. In linear regression analysis, after adjustment for age and gender, BMI was found to be positively related to age, waist circumference, energy and saturated fatty acids (p<0.001) but inversely related to fiber (p<0.001).

Originality/value

The paper gives information to nutritionists and clinical dieticians, including new data about dietary intakes and anthropometric measurements of Cypriot adults.
Design and optimization of microstructure of auxetic materials
Authors: Javadi Akbar A. , Faramarzi Asaad , Farmani Raziyeh
Published: March 2012

Purpose

Auxetic materials differ from conventional materials by the manner in which they respond to stretching; they tend to get fatter when stretched, resulting in a negative Poisson's ratio. The purpose of this paper is to present a numerical methodology for design of microstructure of 2D and 3D auxetic materials with a wide range of different negative Poisson's ratios.

Design/methodology/approach

The proposed methodology is based on a combination of finite element method and a genetic algorithm. The problem is formulated as an optimization problem of finding microstructures with prescribed behavioral requirements. Different microstructures are generated and evolved using the genetic algorithm and the behavior of each microstructure is analyzed using the finite element method to evaluate its fitness in competition with other generated structures.

Findings

Numerical examples show that it is possible to design a large number of new auxetic materials, each with a different value of negative Poisson's ratio.

Originality/value

The proposed methodology can be used as an effective method to tailor new materials with prescribed values of negative (or positive) Poisson's ratio. The methodology can also be used to optimize other material properties.
On the design and implementation of parallel finite element approximate inverses using POSIX threads on multicore systems
Authors: Gravvanis G.A. , Matskanidis P.I. , Giannoutakis K.M. , Lipitakis E.A.
Published: March 2012

Purpose

The purpose of this paper is to propose novel parallel computational techniques for the parallelization of explicit finite element generalized approximate inverse methods, based on Portable Operating System Interface for UniX (POSIX) threads, for multicore systems.

Design/methodology/approach

The authors' main motive for the derivation of the new Parallel Generalized Approximate Inverse Finite Element Matrix algorithmic techniques is that they can be efficiently used in conjunction with explicit preconditioned conjugate gradient‐type schemes on multicore systems. The proposed parallelization technique of the Optimized Banded Generalized Approximate Inverse Finite Element Matrix (OBGAIFEM) algorithm is achieved based on the concept of the “fish bone” approach with the use of a thread pool pattern. Theoretical estimates on the computational complexity of the parallel generalized approximate inverse finite element matrix algorithmic techniques are also derived.

Findings

Application of the proposed method on a two‐dimensional boundary value problem is discussed and numerical results are given on a multicore system using POSIX threads. These results tend to become optimum and are favorably compared to corresponding results from multiprocessor systems, as presented in recent work by Gravvanis et al.

Originality/value

The proposed parallel explicit finite element generalized approximate inverse preconditioning, using approximate factorization and approximate inverse algorithms, is an efficient computational method that is valuable for computer scientists and for scientists and engineers in engineering computations.
European Social Fund in Portugal: a complex question for human resource development
Authors: Tomé Eduardo
Published: March 2012

Purpose

This article aims to review the application of the funds awarded by the European Social Fund (ESF) to Portugal, since 1986, from a human resource development (HRD) perspective.

Design/methodology/approach

Several variables are analyzed: investment, absorption, people, impact of investment, evolution of skills, main programs, supply and demand for training and the role of the state.

Findings

The main conclusion of the paper is that, even if the ESF was extremely important in quantitative terms in Portugal, its qualitative implications were modest.

Research limitations/implications

The Portuguese ESF case should be compared with other national cases in the European Union and elsewhere. The ESF patterns should be compared with other cases of international support made by multinationals, non‐governmental organizations or bodies like the World Bank or the United Nations.

Practical implications

European monetary stability and integration has to be based on social stability and integration. The ESF consequences in the “national” HRD markets may be far‐reaching, effectively defining the main elements of the HRD market. Great attention should be paid to positive impacts while defining the priorities of the ESF intervention.

Social implications

The ESF was responsible for the funding of a very considerable part of the Portuguese training market. Precisely because of that huge importance, quality is a very important issue.

Originality/value

The article is an attempt to analyze and evaluate 20 years of intervention in the HRD field with an international dimension in a relatively poor and struggling country in European terms.
A eulogy for a “bright future”
Authors: L'Huillier Barbara
Published: March 2012

Purpose

This poem aims to present a reflection on the bigger picture of how powerless people are in reality to safeguard their own futures.

Design/methodology/approach

It is a fictional poem.

Findings

The poet considers how outside forces devalue the traditional approaches people have taken towards trying to insulate themselves from life's storms.

Originality/value

This is a unique attempt to look at how people are given a false sense of security regarding the methods people should adopt to safeguard themselves and their families against financial ruin.
Museoparks and re‐enchantment of the museum visits: an approach centred on visual ethnology
Authors: Mencarelli Rémi , Pulh Mathilde
Published: March 2012

Purpose

The purpose of this paper is to identify the structural dimensions of a new museal offer, museoparks, which use edutainment and more generally re‐enchantment strategies.

Design/methodology/approach

To bring out the symbolic dimensions specific to these cultural sites, the methodology used is based on the analysis of photographic media.

Findings

The analysis reveals four main symbolic dimensions structuring these hybrid cultural offers: spectacularization, immersive character, ritualized character, and very intense merchandizing of the experience.

Research limitations/implications

This analysis allows us to update a hybrid, complex and re‐sized form of cultural experience that goes beyond the classic combination identified in the analysis of edutainment strategies (educational and fun dimensions).

Practical implications

From a managerial action perspective, this research provides keys to understanding the strategies proposed by the hybrid offers of museoparks; strategies that might inspire many museum managers eager to imitate them.

Originality/value

This research provides keys for understanding the logic underlying the structuring of the experience offered by cultural institutions.
Multiple‐route job shop scheduling with fixed periodic and age‐dependent preventive maintenance to minimize makespan
Authors: Reza Golmakani Hamid , Namazi Ali
Published: March 2012

Purpose

In many manufacturing systems, machines are subject to preventive maintenance. This paper aims to schedule the operations of jobs and preventive maintenance tasks in such a way that the completion time of jobs and preventive maintenance tasks is minimized.

Design/methodology/approach

An heuristic approach based on artificial immune algorithm is proposed for solving the multiple‐route job shop‐scheduling problem subject to fixed periodic and age‐dependent preventive maintenance tasks. Under fixed periodic assumption, the time between two consecutive preventive maintenance tasks is assumed constant. Under age‐dependent assumption, a preventive maintenance task is triggered if the machine operates for a certain amount of time. The goal is to schedule the jobs and preventive maintenance task subject to makespan minimization.

Findings

In addition to presenting mathematical formulation for the multiple‐route job shop‐scheduling problem, this paper proposes a novel approach by which one can tackle the complexity that is raised in scheduling and sequencing the jobs and the preventive maintenance simultaneously and obtain the required schedule in reasonable time.

Practical implications

Integrating preventive maintenance tasks into the scheduling procedure is vital in many manufacturing systems. Using the proposed approach, one can obtain a schedule that defines the production route through which each part is processed, the time each operation must be started, and when preventive maintenance must be carried out on each machine. This, in turn, results in overall manufacturing cost reduction.

Originality/value

Using the approach proposed in this paper, good solutions, if not optimal, can be obtained for scheduling jobs and preventive maintenance task in one of the most complicated job shop configurations, namely, multiple‐route job shop. Thus, the approach can dominate all other simpler configurations.
Understanding the role of prior product knowledge to information search
Authors: Awasthy Dheeraj , Banerjee Arindam , Banerjee Bibek
Published: March 2012

Purpose

Existing literature offers conflicting evidence on how prior product knowledge influences amount of information search. A majority of these studies are based on variants of cost benefit frameworks where consumers engage in search until the benefits from information search exceed search costs. The purpose of this paper is to develop an expectancy theory‐based framework to model consumers' information search and its antecedents, including motivation to search as an intervening construct.

Design/methodology/approach

The framework is tested using data from real consumers engaged in their actual purchase decisions, in an emerging market context, using longitudinal survey research design. The data are analysed using structural equation modeling to test the hypothesized model. The model shows an acceptable fit with X2 (271, 487)=640.252,p< 0.00 and 0.95 CFI.

Findings

Results indicate that the relationship between prior product knowledge to information search is mediated by motivation to search. Prior product knowledge influences motivation to search through its influence on the consumer's perceived ability to search and his/her perceived value of additional information. Furthermore, perceived ability to search is the strongest predictor of motivation to search. The parsimony of the proposed framework in providing a simpler account of factors influencing the search process along with its managerial implications is discussed.

Practical implications

The findings suggest that perceived ability to search and perceived value of additional information are two important levers that managers could use for achieving desired results. Furthermore, perceived ability to search is an important mediator, which completely mediates the relationship between prior product knowledge and motivation to search. These findings also provide strong indications about the need to simplify the search process for consumers, especially in the context when novelty is predominantly marketed.

Originality/value

The paper introduces a motivational measure of search in the literature and shows that the motivational measure is indeed the proximal measure to other antecedent constructs compared to a behavioral measure of search. Perceived ability to search and perceived value of additional information are shown as important mediators between prior product knowledge and motivation to search.
Reflections on student‐university interactions for next generation learning
Authors: Wong David H.
Published: March 2012

Purpose

The purpose of this paper is to draw attention to the implications of an e‐learning strategy – a strategy that is increasingly employed with greater intensity by many higher education institutions, by re‐examining the value creation process from a service‐dominant logic perspective.

Design/methodology/approach

A model of student‐faculty and student‐student interactions using interactive Web 2.0 technologies in e‐learning is offered and explained using literature from service‐dominant logic research.

Findings

This perspective fundamentally alters the mindset of higher education institutions that have traditionally devised strategies to deliver value through its products and services. The new focus provided by service‐dominant logic is for higher education institutions to acknowledge that they can only facilitate the value creation process by fostering interactions, constructing learning activities that enable enriching learning experiences and creating structures to support these experiences.

Practical implications

Key challenges for higher education institutions are discussed that include implications for exclusion marketing, perceived value for money, and policy issues.

Originality/value

This paper provides a fresh perspective, and a new line of thinking with regard to how value is co‐created by both faculty and students through a set of experiences within student‐faculty and student‐student interactions. It therefore potentially directs a new path of research in the area.
A survey of safety and health at work in Greece
Authors: Drakopoulos Stavros , Economou Athina , Grimani Katerina
Published: March 2012

Purpose

The subject of occupational safety and health (OSH) is increasingly gaining the interest of policy makers and researchers in European countries given that the economic and social losses from work‐related injuries and diseases are quite substantial. Under this light, this paper aims to present an overview of the Greek legislation framework regarding OSH issues, and the current status of empirical research on the subject in Greece. In addition, the paper seeks to identify the knowledge gaps and methodological shortcomings of the existing literature in order to contribute towards future research in the OSH field in Greece.

Design/methodology/approach

The authors conducted an extensive literature review of numerous publications, reports and institutions' databases.

Findings

The results suggest that empirical up to date research in Greece is rather inadequate, mainly because of the absence of econometric methods to validate the findings. The available Greek databases indicate that while the number of working accidents has decreased over time, the severity seems to be increasing. Males are more prone to accidents, diseases and negative working conditions. Work‐related stress is an aspect of occupational problems that has been the subject of many Greek studies.

Research limitations/implications

Although the legal framework is quite adequate, there is a need for both prevention strategies and enforcement of the existing safety regulations. Furthermore, a substantial research gap is observed in Greece. Therefore, more systematic research is needed on the determinants of injuries and on their effects on job participation and productivity.

Originality/value

The paper presents a detailed review of the current state of research regarding OSH issues in Greece.
Inhibin B and luteinizing hormone levels in girls aged 6–11 years from NHANES III, 1988–1994
Authors: Sims Emily K. , Addo O. Y. , Gollenberg Audra L. , Himes John H. , Hediger Mary L. , Lee Peter A.
Published: March 2012

Objective

To evaluate inhibin B and luteinizing hormone (LH) levels in a large, representative cross‐sectional sample of US girls and characterize the relationships of these laboratory values with age, clinical signs of puberty and other correlates.

Design

Cross‐sectional analysis of LH and inhibin B in banked serum from 720 girls aged 6–11 years who participated in the Third National Health and Nutrition Examination Survey (NHANES III).

Measurements

Levels of inhibin B and LH, race, ethnicity and anthropometric measurements were compared for all girls. Visual assessment of pubertal stage was performed on girls aged 8 years and older. A two‐part model was used to establish normative data and Tobit regression models were used to evaluate associations with participant characteristics. Receiver operating characteristic (ROC) analysis was performed to identify optimum cut points predictive of puberty onset.

Results

Mean hormone levels progressively increased with age. LH levels progressively increased with pubertal stage. Inhibin B levels increased gradually from breast stage I to II, then more sharply to peak at stage III, followed by a plateau at stages IV and V. ROC curves indicated that both hormones were consistent with pubertal onset as indicated by breast stage II.

Conclusions

This study characterizes inhibin B and LH values in a large, representative cross‐sectional sample of US girls. Inhibin B can be a useful tool in combination with other clinical and biochemical parameters to evaluate gonadal function as a reflection of pubertal progression in girls.
Unravelling modifiers of breast and ovarian cancer risk for BRCA1 and BRCA2 mutation carriers: update on genetic modifiers
Authors: Barnes D. R. , Antoniou A. C.
Published: March 2012

Abstract.  Barnes DR, Antoniou AC (Centre for Cancer Genetic Epidemiology, University of Cambridge, Cambridge, UK). Unravelling modifiers of breast and ovarian cancer risk for BRCA1 and BRCA2 mutation carriers: update on genetic modifiers (Review). J Intern Med 2012; 271: 331–343

Pathogenic mutations in the tumour suppressor genes BRCA1 and BRCA2 confer increased risks for breast and ovarian cancer and account for approximately 15% of the excess familial risk of breast cancer amongst first‐degree relatives of patients with breast cancer. There is considerable evidence indicating that these risks vary by other genetic and environmental factors clustering in families. In the past few years, based on the availability of genome‐wide association data and samples from large collaborative studies, several common alleles have been found to modify breast or ovarian cancer risk for BRCA1 and BRCA2 mutation carriers. These common alleles explain a small proportion of the genetic variability in breast or ovarian cancer risk for mutation carriers, suggesting more modifiers remain to be identified. We review the so far identified genetic modifiers of breast and ovarian cancer risk and consider the implications for risk prediction. BRCA1 and BRCA2 mutation carriers could be some of the first to benefit from clinical applications of common variants identified through genome‐wide association studies. However, to be able to provide more individualized risk estimates, it will be important to understand how the associations vary with different tumour characteristics and their interactions with other genetic and environmental modifiers.
Cognitive changes in topiramate‐treated patients with alcoholism: A 12‐week prospective study in patients recently detoxified
Authors: Likhitsathian Surinporn , Saengcharnchai Pichai , Uttawichai Kanok , Yingwiwattanapong Jatsada , Wittayanookulluk Apisak , Srisurapanont Manit
Published: March 2012

Aims: The aim of this study was to determine the 12‐week cognitive changes in topiramate‐treated patients recently detoxified from alcohol.

Methods: Participants were inpatients with DSM‐IV alcohol dependence. All of them were discharged within 14 days after the initiation of topiramate treatment. The topiramate dose range was 50–300 mg/day. The Montreal Cognitive Assessment (MoCA) was used on day 0, day 29, day 57, and day 85. Differences of the MoCA total and seven subtest scores among four time‐points were compared.

Results: Thirty‐eight participants (36 men and two women) had a mean ± SD age of 43.1 ± 8.6 years old. At enrollment, they were abstinent for a mean ± SD of 11.5 ± 5.3 days. Five, one, and three patients dropped out of the study on day 29, day 57, and day 85, respectively. On day 85, the mean ± SD dose of topiramate was 253.1 ± 60.8 mg/day. Alcohol consumption decreased drastically during follow up. At each time‐point, 75%–80% of the participants were continuous abstainers. The mean ± SD MoCA total, language subtest, and delayed recall subtest scores increased significantly from day 0 to day 85, from 22.0 ± 4.7 to 24.7 ± 3.4 (P < 0.01), from 1.1 ± 1.0 to 1.3 ± 1.0 (P = 0.03), and from 2.7 ± 1.7 to 4.1 ± 1.0 (P < 0.01), respectively.

Conclusion: Topiramate‐treated patients recently detoxified from alcohol usually have an improvement of their cognitive function, especially in the language and delayed recall domains. This phenomenon may be caused by the greater influence of cognitive recovery associated with decreased drinking as compared with topiramate‐induced cognitive impairment.
Three phases of the Pacific Islands Project (1995–2010)
Authors: Watters David A. K. , Ewing Hamish , McCaig Eddie
Published: March 2012

The Pacific Islands Project (PIP), funded by AusAid and managed by the Royal Australasian College of Surgeons (RACS), has progressed through three phases from 1995 to 2010. During this time, it has sent over 520 teams to 11 Pacific Island Countries, providing over 60 000 consultations and some 16 000 procedures. In addition to this delivery of specialist medical and surgical services that were not previously available in‐country, the project has contributed as a partner in capacity building with the Fiji School of Medicine and Ministries of Health of the individual nations. By 2011, Fiji School of Medicine, which began postgraduate specialist training in 1998, had awarded 51 doctors a diploma in surgery (1 year), 20 of whom had completed their Masters in Medicine (4 years). PIP was independently evaluated on completion of every phase, including the bridging Phase III (2006–2010). The project delivered on its design, to deliver services, and also helped build capacity. The relationship established with the RACS throughout the project allowed Pacific Island graduates to access the Rowan Nicks scholarship, and the majority of MMed graduates received International Travel Grants to attend the Annual Scientific Meeting. PIP has been a highly successful partnership in delivering and building specialist medical services. Although AusAid contributed some $20 million over 16 years, the value added from pro bono contributions by Specialist Teams, Specialty Coordinators and the Project Directors amounted to an equivalent amount. With the emergence of Pacific Island‐trained specialists, PIP is ready to move into a new phase where the agendas are set, monitored and managed within the Pacific, and RACS fulfils the role of a service provider. A critical mass of Pacific Island surgeons has been trained, so that sub‐specialization will be an option for the general surgeons of the larger island nations.
The shadow of familiarity:a contributor to the intersubjective field
Authors: Winborn Mark
Published: March 2012

Abstract:  This paper examines the influence of familiarity on the progress of analysis. It is proposed that familiarity is a particular aspect of the intersubjective field which emerges over time and begins to shape and influence the behaviours, perceptions, thoughts, and feelings of the participants. It is also proposed that states of familiarity can have facilitative or defensive functions in an analytic relationship and that it is an influence co‐created in the field. The experience of familiarity operates as background to our various foreground concerns in analytic work and therefore exists primarily as an implicit, rather than explicit, experience in analysis. Defensive familiarity often creates a feeling of relatedness that is subtly unrelated, a form of pseudo‐intimacy. Parallels between defensive familiarity and related concepts are examined including defences against the unknown, role responsiveness, romantic love, the image of the stranger, and unformulated experience. This paper concludes with two case examples and a discussion of procedural knowledge in the implicit domain as an explanatory framework for the understanding of familiarity states in the analytic setting.
Considering the Risk of Infection by Cryptosporidium via Consumption of Municipally Treated Drinking Water from a Surface Water Source in a Southwestern Ontario Community
Authors: Pintar K. D. M. , Fazil A. , Pollari F. , Waltner‐Toews D. , Charron D. F. , McEwen S. A. , Walton T.
Published: March 2012

Through the use of case‐control analyses and quantitative microbial risk assessment (QMRA), relative risks of transmission of cryptosporidiosis have been evaluated (recreational water exposure vs. drinking water consumption) for a Canadian community with higher than national rates of cryptosporidiosis. A QMRA was developed to assess the risk of Cryptosporidium infection through the consumption of municipally treated drinking water. Simulations were based on site‐specific surface water contamination levels and drinking water treatment log10 reduction capacity for Cryptosporidium. Results suggested that the risk of Cryptosporidium infection via drinking water in the study community, assuming routine operation of the water treatment plant, was negligible (6 infections per 1013 persons per day—5th percentile: 2 infections per 1015 persons per day; 95th percentile: 3 infections per 1012 persons per day). The risk is essentially nonexistent during optimized, routine treatment operations. The study community achieves between 7 and 9 log10Cryptosporidium oocyst reduction through routine water treatment processes. Although these results do not preclude the need for constant vigilance by both water treatment and public health professionals in this community, they suggest that the cause of higher rates of cryptosporidiosis are more likely due to recreational water contact, or perhaps direct animal contact. QMRA can be successfully applied at the community level to identify data gaps, rank relative public health risks, and forecast future risk scenarios. It is most useful when performed in a collaborative way with local stakeholders, from beginning to end of the risk analysis paradigm.
Very Low Loss Tangent and High Dielectric Permittivity in Pure‐CaCu3Ti4O12 Ceramics Prepared by a Modified Sol‐Gel Process
Authors: Vangchangyia Somsack , Swatsitang Ekaphan , Thongbai Prasit , Pinitsoontorn Supree , Yamwong Teerapon , Maensiri Santi , Amornkitbamrung Vittaya , Chindaprasirt Prinya
Published: March 2012

We present a simple strategy to achieve excellent dielectric and nonlinear current–voltage properties for pure–CaCu3Ti4O12 ceramics prepared by a modified sol–gel method with different calcining conditions. At 1 kHz and room temperature, the best CCTO ceramic can exhibit a high dielectric constant (ε′) of 9516 with a very low dielectric loss, tan δ ~0.020. The minimum value of tan δ is 0.018 at 2.5 kHz with ε′ ~9433. High breakdown field of 4032 V/cm and nonlinear coefficient of 7.05 were obtained.
Giant Dielectric Constant and Good Temperature Stability in Y2/3Cu3Ti4O12 Ceramics
Authors: Liang Pengfei , Yang Zupei , Chao Xiaolian , Liu Zonghuai
Published: March 2012

Y2/3Cu3Ti4O12 ceramics were successfully prepared by the conventional solid‐state reaction method. Effects of sintering conditions on microstructure, phase structure, and the dielectric properties of Y2/3Cu3Ti4O12 ceramics were investigated in detail. Y2/3Cu3Ti4O12 ceramics sintered at 1010°C for 25 h exhibited a giant dielectric constant (1.10 × 104) and a relatively low dielectric loss (0.033) around room temperature. The samples showed good temperature stability ( – 9.5%) in the temperature range from −60°C to 125°C at 10 kHz. It was also found that a new dielectric relaxation III appeared at higher temperatures (>200°C). The complex impedance spectroscopy analysis suggested that Y2/3Cu3Ti4O12 ceramics were electrically heterogeneous, and they consisted of semiconducting grains and insulating grain boundaries, which could be modeled to a first approximation on an equivalent circuit based on two parallel RC elements connected in series. The Cu2+/Cu3+ and Ti3+/Ti4+ aliovalences were observed in Y2/3Cu3Ti4O12 ceramics. The giant permittivity phenomenon could be explained by internal barrier layer capacitance (IBLC) effect.
First outbreak of extended‐spectrum β‐lactamase‐producing Klebsiella pneumoniae in a Norwegian neonatal intensive care unit; associated with contaminated breast milk and resolved by strict cohorting
Authors: Rettedal Siren , Löhr Iren H. , Natås Olav , Giske Christian G. , Sundsfjord Arnfinn , Øymar Knut
Published: March 2012

Neonatal intensive care units (NICUs) are vulnerable to nosocomial outbreaks caused by multiresistant Enterobacteriaceae, but no reports of NICU outbreaks of extended‐spectrum β‐lactamase (ESBL) producing Klebsiella pneumoniae have previously been published from countries with a low level of antimicrobial resistance such as the Scandinavian countries. We describe a clonal outbreak of CTX‐M‐15 ‐producing Klebsiella pneumoniae affecting 58 infants in the neonatal intensive care unit at Stavanger University Hospital, Norway, during a period of 4 months, 2008–2009. The clone spread widely and rapidly in the NICU, and extensive interventions were required to terminate the outbreak. In contrast to previous outbreaks, only one infant acquired a systemic infection caused by the outbreak strain, probably due to a favourable epidemic strain lacking the most common virulence factors. A probable index case was identified, due to multiple positive breast milk samples collected from the infant's mother before and after the infant's transfer from another hospital. Breast milk samples from 3/18 (17%) mothers of colonized infants were positive for ESBL‐producing K. pneumoniae. Vertical transmission of ESBL‐producing bacteria has been shown previously,’but the possibility of transmission of ESBL‐producing K. pneumoniae through expressed breast milk is reported here for the first time. The increasing occurrence of ESBL‐producing’Enterobacteriaceae should therefore encourage changes in diagnostic routines for bacterial screening of breast milk.
Human mannose‐binding lectin inhibits human cytomegalovirus infection in human embryonic pulmonary fibroblast
Authors: Wu Wei , Chen Yinghu , Qiao Huiju , Tao Ran , Gu Weizhong , Shang Shiqiang
Published: March 2012

A limited number of drugs have been used for treatment of human cytomegalovirus (HCMV), all sharing the similar antiviral mechanism of inhibiting virus replication. This study investigates the anti‐HCMV activities of mannose‐binding lectin (MBL) from blocking virus entry and inhibiting virus spread. Recombinant human MBL was produced in CHO cells and native human MBL was isolated from human serum. A HCMV neutralization test was performed by pre‐treating HCMV with each diluted MBL solution. Then the treated HCMV was inoculated onto the human embryonic pulmonary fibroblasts (HELF), which was followed by HCMV‐DNA detection, PP65 positivity examination and confocal imaging of the infected cells. To test the activity of MBL in inhibiting viral spreading after viral invasion, HCMV growth inhibition test was performed. The infected cells were incubated with each diluted MBL, every 24 h, the supernatant was tested for HCMV‐DNA. After 72 h, cells were collected for HCMV‐DNA and PP65 examination. Then the cytopathic effect was observed and cell viability was measured at the 5 days after infection. HCMV neutralization test revealed 10 μg/mL MBL significantly decreased the HCMV invasion in HELF and the anti‐HCMV activity can be blocked by 20 mg/mL mannan. HCMV growth inhibition test indicated that at 48 h after HCMV invasion, the HCMV‐DNA level in the culture supernatant with 10 μg/mL MBL was lower than the control. After 72 h, both the HCMV‐DNA levels and PP65 positivity in cells incubated with MBL were reduced. This is the first to report on the anti‐HCMV activities of MBL by in vitro studies.
An integrative model links multiple inputs and signaling pathways to the onset of DNA synthesis in hepatocytes
Authors: Huard Jérémy , Mueller Stephanie , Gilles Ernst D. , Klingmüller Ursula , Klamt Steffen
Published: March 2012

During liver regeneration, quiescent hepatocytes re‐enter the cell cycle to proliferate and compensate for lost tissue. Multiple signals including hepatocyte growth factor, epidermal growth factor, tumor necrosis factor α, interleukin‐6, insulin and transforming growth factor β orchestrate these responses and are integrated during the G1 phase of the cell cycle. To investigate how these inputs influence DNA synthesis as a measure for proliferation, we established a large‐scale integrated logical model connecting multiple signaling pathways and the cell cycle. We constructed our model based upon established literature knowledge, and successively improved and validated its structure using hepatocyte‐specific literature as well as experimental DNA synthesis data. Model analyses showed that activation of the mitogen‐activated protein kinase and phosphatidylinositol 3‐kinase pathways was sufficient and necessary for triggering DNA synthesis. In addition, we identified key species in these pathways that mediate DNA replication. Our model predicted oncogenic mutations that were compared with the COSMIC database, and proposed intervention targets to block hepatocyte growth factor‐induced DNA synthesis, which we validated experimentally. Our integrative approach demonstrates that, despite the complexity and size of the underlying interlaced network, logical modeling enables an integrative understanding of signaling‐controlled proliferation at the cellular level, and thus can provide intervention strategies for distinct perturbation scenarios at various regulatory levels.
Getting the Right Mix of Capital and Cash Requirements in Prudential Bank Regulation*
Authors: Calomiris Charles W.
Published: March 2012

Cash reserve requirements are useful as a broadly conceived prudential tool, not just as a narrowly focused means of limiting the risks associated with illiquidity. Indeed, illiquidity risk is neither a necessary nor a sufficient condition for establishing bank liquidity requirements. The primary means of mitigating the systemic costs of bank illiquidity risk is the creation of an effective lender of last resort (LOLR). But instead of focusing narrowly on bank funding risks when designing liquidity requirements, regulators should consider tradeoffs among capital requirements, liquidity requirements, and LOLR policies for achieving the broader prudential goal of limiting bank default risk.

When considering the optimal tradeoff between capital ratios and cash ratios as prudential requirements, five “frictions” are identified that favor the use of one or the other: (1) the adverse‐selection costs of raising equity (which favors the use of cash); (2) the opportunity cost of forgone abnormal profits (or “quasi rents”) from lending (which favors the use of capital); (3) the limited verifiability of loan outcomes (which favors the use of cash); (4) the moral hazard that results from costly or postponed loss recognition, given the incentive for risk shifting in bad states (which favors the use of cash); and (5) the prospect of changes in the risk environment (which favors cash since it creates greater option value for maintaining targeted default risk with lower adjustment costs in the face of changing loan risk or illiquidity risk).

When viewed from the perspective of achieving the main prudential goal of controlling default risk at a minimum social cost, capital requirements have some limitations that favor liquidity requirements, and vice versa. And thus the optimal regulatory policy will combine liquidity and capital requirements.
Performance Study of a Bi-Cell Piezoelectric Proton Exchange Membrane Fuel Cell With a Nozzle and Diffuser
Authors: Ma Hsiao-Kang , Wang Jyun-Sheng , Su Wei-Han , Cheng Wei-Yang
Published: March 2012

Previous studies of a bi-cell piezoelectric proton exchange membrane fuel cell with a nozzle and diffuser (PZT-PEMFC-ND bi-cell) have shown that the performance of the PZT-PEMFC-ND bi-cell could be 1.6 times greater than that of the single cell when the proper aspect ratio (AR) of 11.25 and the diffuser angle of 5° are applied to the diffuser. In this study, the novel pseudo-bipolar bi-cell module was designated parallel with an 8 cm2 reaction area, an AR of 5.63, and a diffuser angle 10°. The bi-cell module was operated under various operating conditions, including different operating temperatures, bi-cell circuit and intake module on anode, the performance of the bi-cell and the two component cells, and to optimize the integrated system output. The pump performance of the PZT-PEMFC-ND may be influenced by the asymmetric amplitude of the PZT device. The asymmetric amplitude results in different air flow rates through the cathode chamber of the component cells and in different current outputs for the component cells. For the different intake modules, the power of bi-cells at flow parallel and series will produce maximum power as 0.283 W cm−2 and 0.263 W cm−2, respectively. The power consumption of the PZT device should be taken into consideration when determining the net power of the PZT-PEMFC-ND bi-cell. In this study, the maximum net power of the bi-cell was found to be 0.7W.
Modeling Effects of Two-Phase Transport in Cathode Gas Flow Channel on PEM Fuel Cell Performance
Authors: Wang Yun , Chen Ken S.
Published: March 2012

The objective of this study is to make an attempt at developing a sub-model that can account for the presence of liquid water in the cathode channel and couple it with other key phenomena occurring in a PEM fuel cell, including those in the anode side. The two-phase sub-model in cathode gas flow channels is based on the two-phase mixture formula. Numerical results from case studies are presented in comparison with those predicted by the single-phase channel flow sub-model. Our preliminary results indicate that liquid water accumulates along the flow channels and builds up quickly once it emerges. For the operating conditions and cell geometry chosen for the case study present in the present work, our results show that the liquid water in the channel only slightly affects the fuel cell performance. More extensive case studies are needed.
Two-Phase Flow in a Gas Flow Channel of Polymer Electrolyte Fuel Cells
Authors: Cho Sung Chan , Wang Yun
Published: March 2012

Two-phase flow behavior in a mini channel is studied by both experimental and numerical methods. Various surface conditions are considered to capture the fundamental characteristics of water droplet behavior in a PEMFC gas channel. In the considered rectangular channel with 1 mm height, critical velocity for annular flow type is measured as 1∼2 m/s of superficial air velocity. Two-phase flow pattern shows some uncertainty near transition zone with aluminum surface. With carbon paper GDL, two-phase flow pattern is stabilized. Measured two-phase pressure drop data explains the relation between two-phase flow pattern and two-phase pressure drop. Numerical simulation using VOF technique successfully mimicked the development of water droplet and corner flow as well as formation of a slug. It also explains the possibility of random slug formation with aluminum surface and stabilized two-phase flow pattern with carbon paper GDLs.
Vapor Delivery Systems for the Study of the Effects of Reformate Gas Impurities in HT-PEM Fuel Cells
Authors: Araya Samuel Simon , Kær So̸ren Knudsen , Andreasen So̸ren Juhl
Published: March 2012

The reforming of methanol can be an alternative source of hydrogen for fuel cells, since it has many practical advantages over hydrogen, mainly due to the technological limitations related to the storage, supply and distribution of the latter. However, despite the ease of methanol handling, impurities in the reformate gas, produced from methanol steam reforming can affect the performance and durability of fuel cells. In this paper different vapor delivery systems, intended to assist in the study of the effects of some of the impurities, are described and compared with each other. A system based on a pump and electrically heated evaporator was found to be more suitable for the typical flow rates involved in the anode feed of a H3PO4/PBI-based HT-PEMFC unit cell assembly. Test stations composed of vapor delivery system and mass flow controllers for testing the effects of methanol slip, water vapor, CO and CO2 are also illustrated.
Non-Propulsive Miniature Power Device Based on SOFC and Combustion-Driven Thermal Transpiration Pump
Authors: Zeng Pingying , Wang Kang , Ahn Jeongmin
Published: March 2012

A meso/micro-scale self-sustaining power generator that is self-contained, has pumping and power generation integrated into one device, has no moving parts and operates only on thermal and electrochemical energy supplied by hydrocarbon fuels, was demonstrated. A solid oxide fuel cell tested with the device obtained a power of 20 mW/cm2.
Modeling Ultrasonic Sealing of Membrane Electrode Assemblies for High-Temperature PEM Fuel Cells
Authors: Guglielmo Dave C. , Snelson Todd T. B. , Walczyk Daniel F.
Published: March 2012

Ultrasonic bonding, with its extremely fast cycle times and energy efficiency, is being investigated as an important manufacturing technology for future mass production of fuel cells. The objectives of the authors’ research are to (1) create a multi-physics simulation model that predicts through-thickness energy distribution and temperature gradients during ultrasonic sealing of polybenzimidazole (PBI) based Membrane Electrode Assemblies (MEAs) for High Temperature PEM fuel cells, and (2) correlate the model with experimentally measured internal interface (e.g., membrane/catalyst layer) temperatures. The multi-physics model incorporates the electrode and membrane material properties (stiffness and damping) in conjunction with the ultrasonic process parameters including pressure, energy flux and vibration amplitude. Overall, the processing of MEAs with ultrasonic bonding rather than a hydraulic thermal press results in MEAs that meet or exceed required performance specifications, and potentially reduces the manufacturing time from minutes to seconds.