bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of polarization on four-beam laser interference lithography
Authors: Wang Dapeng , Wang Zuobin , Zhang Ziang , Yue Yong , Li Dayou , Maple Carsten
Published: March 2013

This paper demonstrates that polarization plays an important role in the formation of interference patterns, pattern contrasts, and periods in four-beam interference lithography. Three different polarization modes are presented to study the effects of polarization on four-beam laser interference based on theoretical analysis, simulations, and experiments. A four-beam laser interference system was set up to modify the silicon surface. It was found that the secondary periodicity or modulation was the result of the misaligned or unequal incident angles only in the case of the TE-TE-TM-TM mode. The resulting patterns have shown a good correspondence with the theoretical analysis and simulations.
Mechanism of dopant-vacancy association in α-quartz GeO2
Authors: Wang H. , Chroneos A. , Schwingenschlögl U.
Published: March 2013

Improving the electron mobility of devices such as Ge metal oxide semiconductor field effect transistors requires good Ge/dielectric interfaces. GeO2 thus is reconsidered as a passivation layer for Ge. However, O-vacancies need to be controlled as they have a deleterious impact on the properties. We employ electronic structure calculations to investigate the introduction of trivalent ions (Al, Y, and La) in α-quartz GeO2. The binding energies of the dopant-vacancy pairs reveal that dopants can be used to control the O-vacancies and reduce the induced dangling bonds. It is proposed that the introduction of Al will limit the concentration of O-vacancies at low Fermi energy.
Enhanced ultraviolet pulse generation via dual-color filament interaction induced phase-matching control
Authors: Shi Liping , Li Wenxue , Zhou Hui , Wang Di , Ding Liang'en , Zeng Heping
Published: March 2013

We demonstrated efficient generation of intense vacuum ultraviolet pulses at 133 nm directly from a 400-nm filament in argon gas. The conversion efficiency was significantly enhanced by adding a coaxial 267-nm pump pulse to dramatically ameliorate the phase matching conditions, as the dispersion originated from neutral atoms was compensated by additional free electrons stemmed from enhanced ionization induced by dual-color fields. Such a robust all-optical phase-matching control was shown to be dependent upon the pump intensity and temporal delay between the dual-color fields.
The role of interference and polarization effects in the optical visualization of carbon nanotubes
Authors: Carozo Victor , Fragneaud Benjamin , Gustavo Cançado Luiz , Almeida Clara M. , Bedê Pedro M. , Archanjo Braulio S. , Alberto Achete Carlos
Published: March 2013

This manuscript presents an experimental study on the optical visualization of single- and multi-walled carbon nanotubes. Optical micrographs of single-nanotubes and multi-walled carbon nanotubes sitting on SiO2/Si substrates are presented. Atomic force microscopy and Raman spectroscopy analysis provide morphological and structural characterization of the carbon nanotubes. Measurements taking into account different substrates, and also different values of wavelength of the incoming light, show that the optical contrast between the nanotubes and the SiO2 surface strongly depends on these two factors. A model based on interference effects explains the experimental results and establishes a route for substrate engineering that allows direct and fast observation of carbon nanotubes, as well as the measurement of their refractive indexes. Analysis on the polarization properties of the reflected light confirms the strong anisotropy on the optical absorption of carbon nanotubes.
High predation risk for a small mammal: the eastern pygmy-possum (Cercartetus nanus)
Authors: Law Bradley , Chidel Mark , Britton Alf
Published: March 2013

We report high rates of predation within a population of eastern pygmy-possum (Cercartetus nanus) near Sydney, observed during a study of the impacts of logging on the species. Predation by reptiles was observed on six of 61 radio-tracked pygmy-possums, while two were suspected of being taken by raptors. We further investigated predation by sooty owls (Tyto tenebricosa) by identifying remains in pellets. Pygmy-possums comprised 15% of the 126 dietary items identified. Predation occurred at both logged and unlogged sites in our study. We suggest that documented high rates of predation in our study could make the species vulnerable to altered predation regimes, such as influxes of feral predators, and highlight the need for a better understanding of any influence of logging on predator activity.
Friedel–Crafts Chemistry. Part 39. Unprecedented Facile Route to the Synthesis of Benzo[b][1]benzazepines via Intramolecular Friedel–Crafts Cyclialkylations
Authors: El-Aal Hassan A. K. Abd , Khalaf Ali A.
Published: March 2013

A series of six pharmaceutically promising 5,6-dihydro-11H-benzo[b][1]benzazepine derivatives (1c–h) were cleanly prepared by Friedel–Crafts cyclialkylations of nitrogen-containing alkanols in the presence of AlCl3, 85 % H2SO4 or polyphosphoric acid catalysts. The precursor alkanols (13a–f) were readily prepared by reaction of two synthesized carboxylic acid esters (12a, b) with different Grignard reagents. Also, two dibenzo[b,f]azepinones (15a, b) were prepared by Friedel–Crafts cycliacylation and reduced to the corresponding 5,6-dihydro-11H-benzo[b][1]benzazepines (1a, b). Overall, this approach allows easy and efficient access to polytricyclic amines from easily synthesized alkanols or cycloketones. A plausible carbocation mechanism is proposed to account for the results.
PROBING THE INNER REGIONS OF PROTOPLANETARY DISKS WITH CO ABSORPTION LINE SPECTROSCOPY
Authors: McJunkin Matthew , France Kevin , Burgh Eric B. , Herczeg Gregory J. , Schindhelm Rebecca N. , Brown Joanna M. , Brown Alexander
Published: March 2013

Carbon monoxide (CO) is the most commonly used tracer of molecular gas in the inner regions of protoplanetary disks. CO can be used to constrain the excitation and structure of the circumstellar environment. Absorption line spectroscopy provides an accurate assessment of a single line of sight through the protoplanetary disk system, giving more straightforward estimates of column densities and temperatures than CO and molecular hydrogen (H2) emission line studies. We analyze new observations of ultraviolet CO absorption from the Hubble Space Telescope along the sightlines to six classical T Tauri stars. Gas velocities consistent with the stellar velocities, combined with the moderate-to-high disk inclinations, argue against the absorbing CO gas originating in a fast-moving disk wind. We conclude that the far-ultraviolet observations provide a direct measure of the disk atmosphere or possibly a slow disk wind. The CO absorption lines are reproduced by model spectra with column densities in the range N(12CO) ∼ 1016–1018 cm−2 and N(13CO) ∼ 1015–1017 cm−2, rotational temperatures T
rot(CO) ∼ 300–700 K, and Doppler b-values, b ∼ 0.5–1.5 km s−1. We use these results to constrain the line-of-sight density of the warm molecular gas (n
CO ∼ 70–4000 cm−3) and put these observations in context with protoplanetary disk models.
On the equivalence of stochastic completeness and Liouville and Khas’minskii conditions in linear and nonlinear settings
Authors: Mari Luciano , Valtorta Daniele
Published: March 2013

Set in the Riemannian enviroment, the aim of this paper is to present and discuss some equivalent characterizations of the Liouville property relative to special operators, which in some sense are modeled after the

p
p

-Laplacian with potential. In particular, we discuss the equivalence between the Liouville property and the Khas’minskii condition, i.e. the existence of an exhaustion function which is also a supersolution for the operator outside a compact set. This generalizes a previous result obtained by one of the authors.
Emergence of cfr-harbouring coagulase-negative staphylococci among patients receiving linezolid therapy in two hospitals in China
Authors: Yang Xue-Jing , Chen Yan , Yang Qing , Qu Ting-Ting , Liu Li-Lin , Wang Hai-Ping , Yu Yun-Song
Published: March 2013

This study reports on the emergence of cfr-harbouring coagulase-negative staphylococci (CoNS) among patients who received linezolid therapy in two hospitals in Hangzhou, China. The mechanisms of resistance and transmission were analysed for these resistant isolates. Eight Staphylococcus capitis isolates, one Staphylococcus epidermidis isolate and one Staphylococcus hominis isolate, obtained from patients who had received linezolid therapy in two hospitals in Hangzhou, China, were confirmed as linezolid resistant, with MICs ranging from 8 to >256 mg l−1. The linezolid usage data of the ten patients before isolation of the linezolid-resistant CoNS were collected. PFGE analysis showed that the eight S. capitis isolates from the two hospitals belonged to the same clone. Nine of the linezolid-resistant CoNS isolates carried the cfr gene, which was located on plasmids of a similar size. A 5.3 kb fragment containing the cfr gene, revealing 99 % identity to the sequence of the cfr-harbouring plasmid pSS-01 reported previously, was determined by PCR mapping for all cfr-positive isolates, and the cfr gene was flanked by two copies of IS256-like elements. Thus, these results document the emergence of linezolid-resistant CoNS isolates carrying the cfr gene in Hangzhou, China. Effective nosocomial infection control strategies and the judicious use of antibiotics will be required to prevent further spread of this resistance mechanism.
A study of misaligned hole‐entry worn journal bearing operating in turbulent regime
Authors: Ram Nathi , Sharma Satish
Published: March 2013

Purpose

The purpose of this paper is to study theoretically the combined influence of journal misalignment and wear on the performance of a hole‐entry hybrid journal bearing system. The bearing is assumed to be operating in a turbulent regime.

Design/methodology/approach

The modified Reynolds equation based on Constantinescu lubrication theory has been solved by using finite element method together with orifice and capillary restrictors flow equations as a constrain together with appropriate boundary conditions.

Findings

It has been observed that for a symmetric hole‐entry journal bearing configuration the value of h¯min is more for the bearing compensated by orifice restrictor as compared to capillary restrictor when bearing operates in turbulent regime under worn/unworn conditions. From the point of view of stability threshold speed ω¯th, the reduction in the value of ω¯th for capillary compensated bearing is around −3.89 percent whereas for orifice compensated bearing it is −7.85 percent when misaligned worn bearing is operating in turbulent regime.

Originality/value

The present work is original of its kind, in case of misaligned hole‐entry worn journal bearing. The results are quite useful for the bearing designer.
Determinants of knowledge transfer in inter‐firm new product development projects
Authors: Lawson Benn , Potter Antony
Published: March 2013

Purpose

The purpose of this paper is to explore the factors which determine the degree of knowledge transfer in inter‐firm new product development (NPD) projects. The authors test a theoretical model exploring how inter‐firm knowledge transfer is enabled or hindered by a buyer's learning intent, the degree of supplier protectiveness, inter‐firm knowledge ambiguity, and absorptive capacity.

Design/methodology/approach

A sample of 153 R&D intensive manufacturing firms in the UK automotive, aerospace, pharmaceutical, electrical, chemical, and general manufacturing industries was used to test the framework. To analyse the data, two‐step structural equation modeling in AMOS 7.0 was used.

Findings

The results indicate that a buyer's learning intent increases inter‐firm knowledge transfer, but also acts as an incentive for suppliers to protect their knowledge. Such defensive measures increase the degree of inter‐firm knowledge ambiguity, encouraging buyer firms to invest in absorptive capacity as a means to interpret supplier knowledge, but also increase the degree of knowledge transfer.

Practical implications

The paper illustrates the effects of focusing on acquisition, rather than accessing supplier technological knowledge. The paper shows that an overt learning strategy can be detrimental to knowledge transfer between buyer‐supplier, as suppliers react by restricting the flow of information. Organisations are encouraged to consider this dynamic when engaging in multi‐organisational, NPD projects.

Originality/value

The paper examines the dynamics of knowledge transfer within inter‐firm NPD projects, showing how transfer is influenced by the buyer firm's learning intention, supplier's response, characteristics of the relationship and knowledge to be transferred.
Agri‐fresh produce supply chain management: a state‐of‐the‐art literature review
Authors: Shukla Manish , Jharkharia Sanjay
Published: March 2013

Purpose

The purpose of this paper is to present a literature review of the fresh produce supply chain management (FSCM). FSCM includes the processes from the production to consumption of fresh produce (fruits, flowers and vegetables).

Design/methodology/approach

Literature review is done by systematically collecting the existing literature over a period of 20 years (1989‐2009) and classifying it on the basis of structural attributes such as problem context, methodology and the product under consideration. The literature is also categorized according to the geographic region and year of publication.

Findings

There is an increase in interest towards FSCM still there is an absence of a journal with the prime attention towards FSCM. The key finding of this review is that the main interest is towards consumer satisfaction and revenue maximization with post‐harvest waste reduction being a secondary objective. It is revealed from the review that most of the literature is fragmented and is in silos. Lack of demand forecasting, demand and supply mismatch, lesser integrated approach etc are the major causes of concerns.

Research limitations/implications

The authors have taken only the fresh produce (fruits, flowers and vegetables), authors may also look at other perishable items such as milk, meat, etc.

Practical implications

Result shows a product‐problem‐methodology mapping which may serve as a framework for the managers addressing issues in FSCM.

Originality/value

Most of the prior literature reviews are focused on a specific issue such as production planning or inventory management and ignore the broader perspective. There exists a need of having a detailed literature review covering all the operational issues in FSCM. This review fills this gap in the FSCM literature.
The relationship between small business market orientation and environmental uncertainty
Authors: Didonet Simone , Simmons Geoff , Díaz‐Villavicencio Guillermo , Palmer Mark
Published: March 2013

Purpose

While literature has examined market orientation, it is limited with respect to small businesses. More specifically, previous research has not considered empirically the relationship between small business market orientation and environmental uncertainty. Due to resource constraints, smaller businesses are especially vulnerable to environmental uncertainty. To address this, the purpose of this paper is to examine the relationship between environmental uncertainty and small business market orientation.

Design/methodology/approach

Drawing from small business literature, the authors developed a research model advancing and testing hypotheses to address the research aim. An empirical study was conducted with 104 small grocery retailers from Brazil. A questionnaire was administered, divided into two sections relating to measurement of market orientation and the market turbulence and technological turbulence as dimensions of environmental uncertainty. ANOVA technique and a multinominal logistic regression model were employed to analyze the results.

Findings

The findings reinforce the view of market orientation as a dynamic construct which can explain the relationship between small businesses and environmental uncertainty. Small businesses with higher levels of market orientation emphasized responsiveness as a critical dimension in orienting to turbulent markets. The findings also show that aspects of technological turbulence, particularly pertaining to the opportunities for competitive advantage and new ideas for product supply related to higher levels of market orientation.

Originality/value

The paper's findings, addressing a knowledge gap in the small business literature, emphasize the importance of small businesses orienting themselves to the market, particularly in environments characterized by higher levels of market and technological turbulence.
The implementation and usage of an electronic document delivery application in Korea
Authors: Won Lee Ji
Published: March 2013

Purpose

The aim of this paper is to investigate the development and current usage status of dCube, the first electronic document delivery application in Korea; identify the effects of electronic document delivery; and present references to institutions that are considering the creation of similar systems.

Design/methodology/approach

dCube development reports, usage manuals, and interview reports with field experts who were in charge of dCube's development were collected; and statistics data from 2007 to 2012 were analyzed.

Findings

dCube, an open and user‐friendly system, was developed through benchmarking of similar systems and in response to requests from member institutions. Since its development, regular mail use has decreased as dCube usage has highly increased. dCube's turn‐around time is less than one day, compared to three to four days for regular mail.

Originality/value

This study represents a thorough investigation and analysis of the development process and utility of the largest‐scale electronic document delivery application in Korea, whose openness and convenience are good models for other ILL/DDS applications.
Evaluating the likelihood of the adoption of an animal welfare assessment system in European agri‐food supply chains
Authors: Aramyan Lusine , Ingenbleek Paul , Backus Gé , de Roest Kees , Tranter Richard
Published: March 2013

Purpose

The purpose of this paper is to analyse the likelihood of adoption of a recently designed Welfare Assessment System in agri‐food supply chains and the factors affecting the adoption decision. The application is carried out for pig and poultry chains.

Design/methodology/approach

This research consisted of two main components: interviews with retailers in pig and poultry supply chains in eight different EU countries to explore their perceptions towards the adoption possibilities of the welfare assessment system; and a conjoint analysis designed to evaluate the perceived adoption likelihood of the assessment system by different Standards Formulating Organisations (SFOs).

Findings

Stakeholders were found to be especially concerned about the costs of implementation of the system and how it could, or should, be merged with existing assurance schemes. Another conclusion of the study is that the presence of a strong third independent party supporting the implementation of the welfare assessment system would be the most important influence on the decision whether, or not, to adopt it.

Originality/value

This research evaluates the adoption possibilities of a novel Welfare Assessment System and presents the views of different supply chain stakeholders on an adoption of such a system. The main factors affecting the adoption decision are identified and analysed. Contrary to expectations, the costs of adoption of a new welfare assessment system were not considered to be the most important factor affecting the decision of supply chain stakeholders about the adoption of this new welfare system.
Implementation of a Six Sigma project in a 3M division of Brazil
Authors: Pires de Souza Ricardo , Roberto Hékis Hélio , Ambrósio Bezerra Oliveira Lucas , Viegas Queiroz Jamerson , Barbosa Pereira Queiroz Fernanda Cristina , Alexsandro de Medeiros Valentim Ricardo
Published: March 2013

Purpose

The Six Sigma project aims at a continual reduction in process variation, eliminating defects or flaws in products and services, optimizing processes and reducing costs. The purpose of this study is to demonstrate improvements in customer service index (CSI), product cycle time and inventory turnover after implementation of a Six Sigma project.

Design/methodology/approach

This research focused on the value stream mapping of a company process, performed by a multidisciplinary team that implemented a pull production system, the standard operational procedure in machines that were process bottlenecks, and the kanban system.

Findings

After three months of implementation, the authors observed an 11.7 percent reduction in product cycle time, increase in customer service index (CSI) from 93.9 to 97 percent and increase in inventory turnovers from 4.9 to 9.

Originality/value

The project was in accordance with the competitive strategy of the company, which is focused on customer satisfaction and cost reduction.
The differential impact of brand equity on B2B co‐branding
Authors: Kalafatis Stavros P. , Remizova Natalia , Riley Debra , Singh Jaywant
Published: March 2013

Purpose

Co‐branding strategies are now seen increasingly in business‐to‐business (B2B) settings, however, there has been little research in this area. This study aims to investigate the benefits of a B2B co‐branding strategy where the partner brands have different brand equity positions.

Design/methodology/approach

This study employs a scenario approach incorporating three real multimedia software brands and three fictitious brands in nine hypothetical alliances over 97 respondents. Using repeated measures ANOVA, the study examines the balance of benefits derived from brand partnerships between high‐, medium‐ and low‐brand equity levels firms.

Findings

It was found that brands with equivalent equity levels shared the benefits of the co‐branding equally, while lower equity brands benefited more from the alliance than higher equity partners. The results also suggest that very dominant partners gain a greater proportion of functional benefits (such as technical expertise) from the co‐branding strategy.

Research limitations/implications

The study used real and fictitious multimedia software brands in a hypothetical co‐branding strategy, measuring a pre‐defined set of benefits. Different results may be found selecting a different industry setting, brands, and benefits.

Practical implications

Firms sharing equal equity positions can expect to enjoy equivalent benefits from a co‐branding strategy, regardless of how strong the joint equity position is. Before entering asymmetric co‐branding relationships, firms should review the differential benefits expected and ensure that negotiations and success measures reflect the anticipated outcomes. Small firms wishing to pursue a co‐branding partnership with a dominant market player should consider that they are less likely to capture the knowledge‐based benefits from the brand alliance.

Originality/value

This paper is the first to look at the impact of asymmetric brand equity positions in a B2B co‐branding partnership, and adds value to the literature and to practitioner understanding of the role of asymmetry in influencing co‐branding outcomes.
Abstract structure
Authors: Haigh Matthew
Published: March 2013

Purpose

Reflects on the process of summarising research.

Design/methodology/approach

A musical structure is used as a trope for the usual research cycle of distilling reams of data into a short article that is sectioned into meaningful chunks, all of which is summarised in an abstract and represented by a few keywords.

Findings

The reductive process ultimately sublates the empirical world to a series of keywords.

Research limitations/implications

Provides a reflexive break to academic work.

Originality/value

Reflects on the experience of summarising a lengthy research project to a few keywords. Hopefully, the thing is read at the end.
An investigation of ethical climate in a Singaporean accounting firm
Authors: Shafer William E. , Poon Margaret C.C. , Tjosvold Dean
Published: March 2013

Purpose

The primary objective of this study is to examine the moderating influence of professional commitment (PC) on the associations among ethical climate, organizational‐professional conflict (OPC) and organizational commitment (OC) among public accountants. It aims to replicate recent findings on the relationships among ethical climate, OPC and OC. It also aims to extend prior research by investigating the association between ethical climate and both functional specialization and organizational rank in an accounting firm.

Design/methodology/approach

The authors surveyed all professional employees in the Singapore office of an international accounting firm.

Findings

Significant associations were found between ethical climate, OPC and OC. Participants' degree of affective commitment to their profession moderated the relationship between the public interest (benevolent/cosmopolitan) climate and perceived conflict and OC. Specifically, professionally committed employees reported less conflict and greater commitment when they felt the firm placed more emphasis on the public interest. These relationships were not present for employees with lower levels of professional commitment. It was also found that taxation specialists perceived the least emphasis in the firm on serving the public interest.

Originality/value

No prior study has documented the moderating influence of affective professional commitment on the association between ethical climate and accountants' OPC or OC. This finding has important implications, suggesting that accounting firms' ability to retain professionally committed employees will depend in part on the degree to which the firm upholds professional ideals such as serving the public interest. The fact that tax specialists perceived less emphasis on serving the public interest than other functional areas implies that tax practices may be overemphasizing client advocacy at the expense of public service.
Ecological variation in leaf biomechanics and its scaling with tissue structure across three mediterranean‐climate plant communities
Authors: Méndez‐Alonzo Rodrigo , Ewers Frank W. , Sack Lawren
Published: March 2013

The mechanical resistance of leaves has key ecological implications but its basis has not been well understood, particularly at the tissue scale. We tested the hypotheses that leaf mechanical resistance should be a function of tissue density, increasing from the lamina to the midrib, and higher in drought‐tolerant than drought‐avoiding species.

In a common garden study, we quantified nine leaf biomechanical traits, including measurements of material and structural resistance, and in addition 17 morphological traits, at the tissue and whole‐leaf scales, for 21 species from three semi‐arid communities of California, USA.

The mechanical properties of leaves depended strongly on tissue density. Material resistance was significantly greater in the midrib than in the leaf lamina, and tissue resistances were significantly correlated among tissues, lower in deciduous coastal sage species and higher in evergreen drought‐tolerant chaparral species. The proportion of the biomass invested in the midrib was lower in species bearing midribs and laminas of high material resistance.

Our results support the hypothesis of a hierarchical partitioning of leaf mechanical resistance among leaf tissues reflecting the investment of dry mass. Also, our data indicated a mechanical compensation in leaf design, where leaves with high material resistance and density deploy a relatively minor proportion of support tissue in the midrib. Finally, our results establish a quantitative basis for differences among communities in leaf biomechanics. Our results supported the classical characterization of the mediterranean‐climate flora of California according to the dramatic increase in the mean leaf mechanical resistance from species of coastal sage to chaparral, with diverse leaf types in the Mojave Desert species.
Political Constitutionalism and the European Union
Authors: Wilkinson Michael A.
Published: March 2013

What kind of constitution is emerging in Europe? There are two approaches to answering this question. The first, a ‘foundational’ approach, rejects the premise: there can be no real constitution in the absence of a ‘demos’, a foundation which exists only nationally. The second, ‘freestanding’ approach, depicts it as paradigmatic of a broader phenomenon of cosmopolitan constitutionalism, based on individual rights guaranteed through a transnational rule of law. Rejecting both for their failure to account for European constitutionalism as a historical process of polity‐building, a third approach, ‘political constitutionalism’, is proposed, capturing the dynamic quality of constitutionalisation in the EU. From this perspective, what is emerging in Europe is a constitution that reflects a common good (predominantly conceived in economic terms), albeit one which is legally, political and socially contested. It is by capturing this complex picture of the political formation of Europe that the constitutional question will be most fruitfully pursued.
Environmental Enforcement Undertakings and Possible Implications: Responsive, Smarter or Rent Seeking?
Authors: Pedersen Ole W.
Published: March 2013

Enforcement undertakings have recently been added to the Environment Agency's list of mechanisms available for the enforcement of certain environmental offences. An enforcement undertaking is a written agreement between the regulator and the offender in which the offender proposes to undertake particular actions in relation to the relevant non‐compliant activity. This article examines the use of enforcement undertakings by the Environment Agency, arguing that the undertakings have significant regulatory implications and give rise to a series of possible problems. Notwithstanding this, the article concludes that enforcement undertakings possess a number of potentially positive features, making them a useful alternative to existing enforcement mechanisms.
Impact of Different Types of Resuscitation Fluids on Coagulation and Continuous Venovenous Hemofiltration Hemocompatibility in a Porcine Model
Authors: Bedarf Janis Rebecca , Grosch‐Ott Sascha , Russ Martin , Wagner Johanna Josophina , Hiebl Bernhard , Kirschfink Michael , Unger Juliane Katharina
Published: March 2013

Intensive therapy demanding diseases (organ failure or sepsis) are assumed to be the etiology behind a decreased biocompatibility of extracorporeal systems for renal replacement therapy (RRT). There are also potential interactions between different components of the overall therapy. Volume substitutes are known to influence hemorheology and coagulation. To define a potential net effect of volume substitutes on the hemocompatibility of an RRT, we chose an animal model without interfering pathophysiologies. According to the problem of early filter failure and coagulation disorders in critically ill patients, we focused on the hypothesized interaction between RRT and different volume substitutes with respect to blood cell counts, coagulation parameters and required heparin dose. Forty‐eight pigs were assigned to four groups of fluid therapy with either normal saline (NaCl), 6%HES130kD/0.4 (HES130), 6%HES200kD/0.5 (HES200) or 4%gelatin (GEL). Six pigs of each fluid group underwent continuous venovenous hemofiltration (CVVH), the remaining six served as the control group. Anticoagulation was performed with continuous heparin infusion. CVVH was run in a recirculation‐mode for 4.5 h to force hemocompatibility reactions, thereafter in a standard‐mode for 2 h. During the CVVH‐treatment GEL reduced platelet counts and fibrinogen concentration and additionally lowered ATIII levels. Heparin requirements did not differ between different volume substitutes or CVVH and control groups. Severe pathophysiologies are not the only reason for a reduced hemocompatibility of CVVH treatment. Interaction of a particular volume substitute with CVVH should be considered when interpreting study results and evolving new strategies.
Oxidative stress activates a specific p53 transcriptional response that regulates cellular senescence and aging
Authors: Gambino Valentina , De Michele Giulia , Venezia Oriella , Migliaccio Pierluigi , Dall'Olio Valentina , Bernard Loris , Minardi Simone Paolo , Fazia Maria Agnese Della , Bartoli Daniela , Servillo Giuseppe , Alcalay Myriam , Luzi Lucilla , Giorgio Marco , Scrable Heidi , Pelicci Pier Giuseppe , Migliaccio Enrica
Published: March 2013

Oxidative stress is a determining factor of cellular senescence and aging and a potent inducer of the tumour‐suppressor p53. Resistance to oxidative stress correlates with delayed aging in mammals, in the absence of accelerated tumorigenesis, suggesting inactivation of selected p53‐downstream pathways. We investigated p53 regulation in mice carrying deletion of p66, a mutation that retards aging and confers cellular resistance and systemic resistance to oxidative stress. We identified a transcriptional network of ~200 genes that are repressed by p53 and encode for determinants of progression through mitosis or suppression of senescence. They are selectively down‐regulated in cultured fibroblasts after oxidative stress, and, in vivo, in proliferating tissues and during physiological aging. Selectivity is imposed by p66 expression and activation of p44/p53 (also named Delta40p53), a p53 isoform that accelerates aging and prevents mitosis after protein damage. p66 deletion retards aging and increases longevity of p44/p53 transgenic mice. Thus, oxidative stress activates a specific p53 transcriptional response, mediated by p44/p53 and p66, which regulates cellular senescence and aging.
Weight loss interventions in asthma: EAACI Evidence‐Based Clinical Practice Guideline (Part I)
Authors: Moreira A. , Bonini M. , Garcia‐Larsen V. , Bonini S. , Del Giacco S. R. , Agache I. , Fonseca J. , Papadopoulos N. G. , Carlsen K.‐H. , Delgado L. , Haahtela T.
Published: March 2013

Background

Asthma and obesity are chronic multifactorial conditions that are associated with gene–environment interaction and immune function. Although the data are not fully consistent, it seems that obesity increases the risk of asthma and compromises asthma control.

Objective

To investigate the impact that weight changes have on asthma.

Methods

We carried out a systematic review of three large biomedical databases. Studies were scrutinized and critically appraised according to agreed exclusion and inclusion criteria. Quality assessment of eligible papers was conducted using the GRADE method. Meta‐analyses of comparable studies were carried out.

Results

Thirty studies met the eligibility criteria of the review. Interventions were limited to dietary manipulation in three studies, one of which also used anti‐obesity drugs, and bariatric surgery in four. All the other studies reported observational data. Becoming obese increased the odds for incident asthma by 1.82 (95% CI 1.47, 2.25) in adults and 1.98 (95% CI 0.71, 5.52) in children. Weight loss was associated with significant improvement in mean scores for symptoms, rescue medication score, and asthma exacerbations in the only randomized controlled trial. Similarly, evidence gathered from observational studies, with follow‐up ranging between 8 weeks to 1 year, and from changes 1 year after bariatric surgery showed improvements in all asthma control‐related outcomes. Changes in lung function were reported in one randomized controlled and eight observational studies of asthmatic subjects, with conflicting results. Either improvement after weight loss, decline with weight gain, or no effects at all were reported. Changes in airway inflammation and responsiveness were reported only by observational studies.

Conclusion

Weight increases above the obesity threshold significantly increase the risk of asthma. The available studies show weak evidence of benefits from weight reduction on asthma outcomes.
Response Inhibition in Preschoolers at Familial Risk for Attention Deficit Hyperactivity Disorder: A Behavioral and Electrophysiological Stop‐Signal Study
Authors: Berger Andrea , Alyagon Uri , Hadaya Hadas , Atzaba‐Poria Naama , Auerbach Judith G.
Published: March 2013

Children participating in the Ben‐Gurion Infant Development Study were assessed with a dynamic‐tracking version of the stop‐signal task at the age of 5 years. The sample consisted of 60 males. Stop‐signal reaction time (SSRT) was correlated with concurrent ratings of the child's attention deficit hyperactivity disorder (ADHD) symptoms. Paternal symptoms measured in the child's early infancy predicted the child's performance in the stop‐signal task: Paternal inattentiveness predicted SSRT, whereas hyperactivity predicted error proportion. Maternal symptoms were not correlated with the performance of the child in the task. A subsample of children, who were tested while electrophysiological brain activity was measured, showed that having higher ADHD symptomatology, especially hyperactivity, correlated with less activity in the brain areas that are usually recruited by children for successful inhibition.
Immunophenotypic characterization of lymphoid cell infiltrates in vitiligo
Authors: Sanchez-Sosa S , Aguirre-Lombardo M , Jimenez-Brito G , Ruiz-Argüelles A
Published: March 2013

The pathogenesis of vitiligo is still controversial. The purpose of this study was to gain insight into the nature of lymphoid cells infiltrating depigmented areas of skin in vitiligo. Immunochemical procedures were carried out in biopsies from 20 patients with active lesions to search for cells expressing CD1a, CD2, CD3, CD4, CD5, CD8, CD20, CD25, CD30, CD56, CD68 and CD79a. Results indicate that early lesions are infiltrated mainly by dendritic cells, whereas older lesions display significantly lower proportions of these cells and increased percentages of mature T cells. This finding might suggest that the autoimmune reactivity towards melanocyte antigens might be T cell-dependent and antigen-driven. It is possible that a non-immune offence of melanocytes is responsible for the exposure of intracellular antigens, while autoreactivity might be a secondary, self-perpetuating mechanism.
Soil sulphur speciation in two glacier forefield soil chronosequences assessed by SK‐edge XANES spectroscopy
Authors: Prietzel J. , Wu Y. , Dümig A. , Zhou J. , Klysubun W.
Published: March 2013

In regions with little atmospheric input of sulphur (S) and S‐poor parent material, the bio‐availability of S, which is dependent on its speciation, may limit ecosystem production and succession. In our study, soil S speciation in two glacier forefield soil chronosequences (Hailuogou Glacier, Gongga Shan, China; Damma Glacier, Swiss Alps) was investigated for the first time. Different S species were quantified by synchrotron‐based X‐ray absorption near‐edge structure (XANES) spectroscopy at the S K‐edge. Both chronosequences show similar patterns and pedogenetic trends of their topsoil S status. Topsoil concentrations of total S were correlated with the concentrations of organic carbon and pedogenic Fe/Al oxyhydroxides. Both moraine materials contained inorganic sulphides, which in the topsoil were oxidized within 30 (Hailuogou) or 75 years (Damma) of soil development after deglaciation. About 50% of total S in the fresh moraine material at Hailuogou and 75% of that in the 15 year‐old soil at Damma was organically‐bound. During initial soil development, the contribution of organic S to total S increased at the expense of inorganic sulphide and sulphate, resulting in organic S percentages > 90% of total topsoil S after 30 (Hailuogou) and 75 (Damma) years of pedogenesis. Organic S compounds with electronic oxidation states of the S atom > + 1.5 (sulphoxides, sulphones, sulphonates and ester sulphates) dominated the organic S pool in all soils. Hence, microbial degradation of non‐sulphide organic S (sulphonates and ester sulphates) is probably important to mitigate S scarcity caused by limited availability of SO42−‐S in these soils. Changes in topsoil S speciation during initial stages of pedogenesis and ecosystem succession in glacier forefields under a cool, humid climate appear to be governed by combined effects of mineral weathering (oxidation of inorganic sulphides and formation of S‐adsorbing sesquioxides), accumulation and microbial turnover of soil organic matter and the type of vegetation succession.
Suicidal ideation and behavior screening in intractable focal epilepsy eligible for drug trials
Authors: Hesdorffer Dale C. , French Jacqueline A. , Posner Kelly , DiVentura Bree , Pollard John R. , Sperling Michael R. , Harden Cynthia L. , Krauss Gregory L. , Kanner Andres M.
Published: March 2013

Purpose

Three suicidal ideation and suicidal behavior instruments were used to assess the prevalence of lifetime and recent suicidal ideation and suicidal behavior in patients with frequent treatment‐resistant focal seizures who would be eligible for randomized clinical trials. This was done to determine which instrument was optimal for use in epilepsy.

Methods

In a cross‐sectional study, we compared lifetime and recent suicidal ideation and suicide attempt on the MINI International Neuropsychiatric Interview (MINI), Columbia Suicide Severity Rating Scale (C‐SSRS), and Interactive Voice Response System CSSRS (E‐CSSRS). A safety algorithm determined treatment referral. Coordinators and participants evaluated experiences with the C‐SSRS. The proportion of participants that baseline assessment would exclude from clinical trial enrollment was determined.

Key Findings

Among 208 participants, 1.6–3.9% had recent high risk suicidal ideation and 1.0–4.7% had a recent suicide attempt across all instruments. Lifetime high‐risk suicidal ideation occurred in 12.1–14.1%. Lifetime suicide attempt occurred in 10.2–13.1% of participants. Of those with recent suicide attempt, 31.1% required referral to a health professional, and 3.9% needed urgent referral. Lifetime suicidal behavior (including aborted suicide attempt, interrupted suicide attempt, suicide attempt, preparatory acts or behavior, and nonsuicidal self‐injurious behavior) was found in 21.1% on the E‐CSSRS and 15.5% on the C‐SSRS. Agreement (Kappa) was good to excellent for comparisons of all instruments. Fifty‐two percent of subjects preferred either the CSSRS or E‐CSSRS, whereas the rest had no preference; of those having a preference, 87.5% favored the CSSRS. Of the 18.9% of participants who might have been excluded from trials based on suicidal ideation and suicide attempt, the CSSRS identified high‐risk suicidal ideation or suicide attempt in the preceding 2 years in only 4.4%.

Significance

Suicidality screening is feasible in people with epilepsy. Slightly more suicidal behavior is reported with the E‐CSSRS than C‐SSRS, suggesting the E‐CSSRS may be optimal. The proportion of patients who may be excluded from clinical trials based on worrisome suicidal ideation or suicide attempt is small, suggesting that it is possible to enroll most eligible individuals.
Association between prosthetic factors and temporomandibular disorders in complete denture wearers
Authors: Ribeiro Jaiane Augusta Medeiros , de Resende Camila Maria Bastos Machado , Lopes Ana Lílian Correia , Farias‐Neto Arcelino , Carreiro Adriana da Fonte Porto
Published: March 2013

Objective

The purpose of this study was to investigate the prevalence of temporomandibular disorders (TMD) in denture wearers and the association between prosthetic factors and this condition.

Background

There is no consensus about the relationship between prosthetic factors and TMD among denture wearers.

Materials and methods

The sample was composed of 92 patients wearing both maxillary and mandibular complete dentures. The Research Diagnostic Criteria for TMD (RDC/TMD) were adopted for patient examination. Objective evaluation of denture quality was determined by analysis of retention and stability of mandibular denture, interocclusal distance, articulation and occlusion. Association between denture quality and TMD diagnosis was analysed using chi‐square and Fisher's exact tests.

Results

37.4% of the patients presented TMD. Denture quality was not significantly associated with the presence of TMD: mandibular retention (p = 0.466); mandibular stability (p = 0.466); interocclusal distance (p = 0.328); centric relation (p = 0.175); and balanced occlusion (p = 0.56).

Conclusion

Within the scope of this case‐controlled cross‐sectional study, no robust association between prosthetic factors and TMD was found.
A cross‐sectional study on dermatological diseases among male prisoners in southernLazio,Italy
Authors: Mannocci Alice , Di Thiene Domitilla , Semyonov Leda , Boccia Antonio , La Torre Guiseppe
Published: March 2013

Background

Prisoners have heightened health needs, and only recently has the importance of skin diseases in this group been recognized. The aim of this study was to estimate the prevalences of dermatological diseases among prisoners in the jails of southernLazio and to investigate the determinants of these.

Methods

A cross‐sectional study was carried out in three jails in southernLazio. Retrospective data collection for sociodemographic characteristics, lifestyle habits, and health status was realized using patients' charts.

Results

The study sample consisted of 2653 male prisoners detained during 1995–2000. A total of 7.9% of the sample were found to have dermatological disease. The most common diseases were nonspecific dermatitis (3.1%), acne (1.5%), mycosis (1.4%), and scabies (0.7%). Multiple regression analyses were conducted to establish the associations of skin diseases with substance addiction status and age. In addition, a highly significant association emerged between length of detention and rate of dermatological disease.

Conclusions

This study shows that habitual offenders, foreign inmates, prisoners serving long sentences, and prisoners who are illiterate are the most affected by dermatological disease. The conditions of detention may be the main reason; preventative strategies such as limiting overcrowding and the provision of electronic case sheets and a centralized database to collect and maintain patient clinical data might be effective in improving public health in jails.