bluuebunny/crossref_metadata_2025 huggingface dataset:
Using a Dual-Sourcing Option in the Presence of Asymmetric Information About Supplier Reliability: Competition vs. Diversification
Authors: Yang Zhibin (Ben) , Aydın Göker , Babich Volodymyr , Beil Damian R.
Published: January 2012

We study a buyer's strategic use of a dual-sourcing option when facing suppliers possessing private information about their disruption likelihood. We solve for the buyer's optimal procurement contract. We show that the optimal contract can be interpreted as the buyer choosing between diversification and competition benefits. Better information increases diversification benefits and decreases competition benefits. Therefore, with better information the buyer is more inclined to diversify. Moreover, better information may increase or decrease the value of the dual-sourcing option, depending on the buyer's unit revenue: for large revenue, the buyer uses the dual sourcing option for diversification, the benefits of which increase with information; for small revenue, the buyer uses the dual sourcing option for competition, the benefits of which decrease with information. Surprisingly, as the reliability of the entire supply base decreases, the buyer may stop diversifying under asymmetric information (to leverage competition), whereas it would never do so under symmetric information. Finally, we analyze the effect of codependence between supply disruptions. We find that lower codependence leads the buyer to rely less on competition. Because competition keeps the information costs in check, a reduction in supplier codependence increases the buyer's value of information. Therefore, strategic actions to reduce codependence between supplier disruptions should not be seen as a substitute for learning about suppliers' reliabilities.
OM Forum—Some Lessons on Operations Management Model Implementation Drawn from the RAND Fire Project
Authors: Kolesar Peter J.
Published: January 2012

This article examines the contributions and historical context of the fire project that was undertaken in the early 1970s by the New York City–RAND Institute on behalf of the New York City Fire Department. We identify a number of technical and nontechnical factors that contributed to the high impact of this operations modeling effort. We hypothesize that these factors, though derived from the experiences in a particular public sector engagement, are applicable to other large-scale operations modeling efforts. This invited contribution is based on the author's inaugural Manufacturing and Service Operations Management (MSOM) Distinguished Fellows address that was given at the June 2011 MSOM conference at the University of Michigan.
Novel general halogen-free methodology for the synthesis of organophosphorus compounds
Authors: Gusarova Nina K. , Arbuzova Svetlana N. , Trofimov Boris A.
Published: January 2012

The use of novel general halogen-free methodology for the synthesis of phosphines, phosphine chalcogenides, and phosphinic acids from elemental phosphorus and alkenes and alkynes in the superbase suspensions is described.
Multicenter Analysis of Quality Indicators for Children Treated in the Emergency Department for Asthma
Authors: Sills Marion R. , Ginde Adit A. , Clark Sunday , Camargo Carlos A.
Published: January 2012

OBJECTIVE:

To test the hypothesis that an association exists between process and outcome measures of the quality of acute asthma care provided to children in the emergency department.

METHODS:

Investigators at 14 US sites prospectively enrolled consecutive children 2 to 17 years of age presenting to the emergency department with acute asthma. In models adjusted for variables commonly associated with the quality of acute asthma care, we measured the association between 7 measures of concordance with national asthma guideline-recommended processes and 2 outcomes. Specifically, we modeled the association between 5 receipt/nonreceipt process measures and successful discharge and the association between 2 timeliness measures and admission.

RESULTS:

In this cohort of 1426 patients, 62% were discharged without relapse or ongoing symptoms (successful discharge), 15% were discharged with relapse or ongoing symptoms, and 24% were admitted. The composite score for receipt of all 5 receipt/nonreceipt process measures was 84%, and for timeliness measures, 57% receive a timely corticosteroid and 92% a timely β-agonist. Our adjusted models showed no association between process and outcome measures, with 1 exception: timely β-agonist administration was associated with admission, likely reflecting confounding by severity rather than a true process-outcome association.

CONCLUSIONS:

We found no clinically significant association between process and outcome quality measures in the delivery of asthma-related care to children in a multicenter study. Although the quality of emergency department care does not predict successful discharge, other factors, such as outpatient care, may better predict outcomes.
Lead Poisoning in United States-Bound Refugee Children: Thailand-Burma Border, 2009
Authors: Mitchell Tarissa , Jentes Emily , Ortega Luis , Scalia Sucosky Marissa , Jefferies Taran , Bajcevic Predrag , Parr Valentina , Jones Warren , Brown Mary Jean , Painter John
Published: January 2012

BACKGROUND:

Elevated blood lead levels lead to permanent neurocognitive sequelae in children. Resettled refugee children in the United States are considered at high risk for elevated blood lead levels, but the prevalence of and risk factors for elevated blood lead levels before resettlement have not been described.

METHODS:

Blood samples from children aged 6 months to 14 years from refugee camps in Thailand were tested for lead and hemoglobin. Sixty-seven children with elevated blood lead levels (venous ≥10 µg/dL) or undetectable (capillary <3.3 µg/dL) blood lead levels participated in a case-control study.

RESULTS:

Of 642 children, 33 (5.1%) had elevated blood lead levels. Children aged <2 years had the highest prevalence (14.5%). Among children aged <2 years included in a case-control study, elevated blood lead levels risk factors included hemoglobin <10 g/dL, exposure to car batteries, and taking traditional medicines.

CONCLUSIONS:

The prevalence of elevated blood lead levels among tested US-bound Burmese refugee children was higher than the current US prevalence, and was especially high among children <2 years old. Refugee children may arrive in the United States with elevated blood lead levels. A population-specific understanding of preexisting lead exposures can enhance postarrival lead-poisoning prevention efforts, based on Centers for Disease Control and Prevention recommendations for resettled refugee children, and can lead to remediation efforts overseas.
Pertussis Pseudo-outbreak Linked to Specimens Contaminated by Bordetella pertussis DNA From Clinic Surfaces
Authors: Mandal Sema , Tatti Kathleen M. , Woods-Stout Denise , Cassiday Pamela K. , Faulkner Amanda E. , Griffith Matthew M. , Jackson Michael L. , Pawloski Lucia C. , Wagner Bari , Barnes Meghan , Cohn Amanda C. , Gershman Ken A. , Messonnier Nancy E. , Clark Thomas A. , Tondella Maria-Lucia C. , Martin Stacey W.
Published: January 2012

BACKGROUND AND OBJECTIVES:

We investigated a pertussis outbreak characterized by atypical cases, confirmed by polymerase chain reaction (PCR) alone at a single laboratory, which persisted despite high vaccine coverage and routine control measures. We aimed to determine whether Bordetella pertussis was the causative agent and advise on control interventions.

METHODS:

We conducted case ascertainment, confirmatory testing for pertussis and other pathogens, and an assessment for possible sources of specimen contamination, including a survey of clinic practices, sampling clinics for B pertussis DNA, and review of laboratory quality indicators.

RESULTS:

Between November 28, 2008, and September 4, 2009, 125 cases were reported, of which 92 (74%) were PCR positive. Cases occurring after April 2009 (n = 79; 63%) had fewer classic pertussis symptoms (63% vs 98%; P < .01), smaller amounts of B pertussis DNA (mean PCR cycle threshold value: 40.9 vs 33.1; P < .01), and a greater proportion of PCR-positive results (34% vs 6%; P < .01). Cultures and serology for B pertussis were negative. Other common respiratory pathogens were detected. We identified factors that likely resulted in specimen contamination at the point of collection: environmentally present B pertussis DNA in clinics from vaccine, clinic standard specimen collection practices, use of liquid transport medium, and lack of clinically relevant PCR cutoffs.

CONCLUSIONS:

A summer pertussis pseudo-outbreak, multifactorial in cause, likely occurred. Recommendations beyond standard practice were made to providers on specimen collection and environmental cleaning, and to laboratories on standardizing PCR protocols and reporting results, to minimize false-positive results from contaminated clinical specimens.
Diffusion Instability and Tapering of Nickel Silicide Intrusions in Silicon Nanowires
Authors: Katsman Alex , Beregovsky Michael , Yaish Yuval E.
Published: January 2012

Thermally activated axial intrusion of nickel silicides into the silicon nanowire (NW) from pre-patterned Ni reservoirs is used in formation of nickel silicide/silicon contacts in SiNW field effect transistors. This intrusion consists usually of different nickel silicide phases which grow simultaneously during thermal annealing (TA). The growth is often accompanied by local thickening and tapering of the NW, up to full disintegration of segments adjacent to the silicon. In the present work this process was investigated in SiNWs of 30-60 nm in diameters with pre-patterned Ni electrodes after a TA at 420-440°C and times up to 15 s. The process was analyzed in the framework of a model taking into account simultaneous formation of two silicide phases in the NW. Additional flux of atoms caused by the NW curvature gradients due to different radii of different silicides was taken into account as well. For a certain set of parameters thickening of the nickel-rich silicide intrusion and tapering of the monosilicide part of intrusion were obtained.
Posttreatment Quantification of Patient Experiences With Full-Arch Implant Treatment Using a Modification of the OHIP-14 Questionnaire
Authors: Babbush Charles A
Published: January 2012

Patient well-being is always the goal of rehabilitation of edentulism; however, evaluations of treatment success often overlook the patient's subjective feelings about comfort, function, speech, social image, social inhibitions, psychological discomfort, and/or disabilities. The purpose of this study was to assess these patient responses using an oral health questionnaire. To assess such feelings, a self-administered 20-question multiple-choice patient-reported Edentulous Patient Impact Questionnaire was developed, based upon the previously validated Oral Health Impact Profile patient-assessment tool. Responses were solicited from randomly selected patients treated with an implant-supported, fixed, immediately loaded full arch prosthesis. The questionnaires were completed by 250 patients. Of the respondents, 95% described themselves as being either extremely satisfied (74%) or satisfied (21%) with their new teeth, and 98% said they would definitely recommend similar treatment (88%) or consider recommending it (10%) to a friend or colleague. Based upon an oral health impact survey completed by 250 patients treated with full-arch implant-supported, immediately loaded fixed dental prostheses, it appears that patient satisfaction is high and that treated patients would generally be willing to recommend this treatment to others.
Desempenho dos arranjos institucionais e minimização dos custos de transação: transações entre produtores e fecularias de mandioca
Authors: Vilpoux Olivier
Published: January 2012

No Brasil, a falta de competitividade do setor de fécula de mandioca em relação ao amido de milho é explicada pelas dificuldades em obter matéria-prima - raízes de mandioca - em quantidades e preços estáveis. A resolução desses problemas envolve a adoção de arranjos institucionais que estabilizam as transações entre produtores e industriais. A análise de 37 fecularias permitiu avaliar as características das transações e o desempenho dos arranjos adotados, medido por meio da capacidade das empresas em estabilizar seu fornecimento de matéria-prima. Os arranjos institucionais encontrados foram classificados em seis tipos, do mercado até a integração vertical, em função do nível de garantia oferecido para entrega de matéria-prima. Apesar da existência de especificidade dos ativos e de incerteza, as empresas preferem as transações via mercado spot, arranjo identificado como menos eficiente. A incerteza ligada ao funcionamento das instituições aumenta os custos de transação dos arranjos contratuais, o que explica a preferência dos atores pelo mercado. Os acordos contratuais com garantias intermediárias e fortes foram mais eficientes, mas com maiores custos de transação. Os resultados indicam dois caminhos para melhorar a competitividade do setor: (1) melhoria na eficiência do mercado, sistema com menores custos de transação; (2) redução dos custos de transação dos arranjos institucionais com maiores garantias, o que proporcionaria sistemas mais eficientes. Enquanto nenhuma dessas soluções for adotada, as fecularias brasileiras continuarão com arranjos de baixos custos de transação, mas fraco desempenho.
Explicando as diferenças de pobreza entre produtores agrícolas no Brasil: simulações contrafactuais com o censo agropecuário 1995-96
Authors: Helfand Steven M. , Moreira Ajax Reynaldo Bello , Figueiredo Adriano Marcos Rodrigues
Published: January 2012

O censo agropecuário 1995-96 é utilizado para estudar os fatores responsáveis pelas diferenças na pobreza entre os estabelecimentos agrícolas no Brasil. As diferenças entre as regiões e as seguintes dicotomias são analisadas: proprietários/não proprietários; familiares/não familiares; intensivos em insumos/não intensivos; com/sem máquinas. O artigo utiliza uma metodologia semiparamétrica. Primeiro, uma função fronteira estocástica de lucro é estimada. Em seguida, simulações não paramétricas contrafactuais são utilizadas para identificar os fatores que explicam as diferenças em pobreza. Os fatores incluem o tamanho da propriedade, o trabalho familiar, a lucratividade e as variáveis utilizadas para explicar a lucratividade no modelo de fronteira estocástica. O artigo conclui que a falta de terra e os baixos níveis de produtividade são importantes motivos para a pobreza entre produtores agrícolas. É improvável que qualquer um deles isoladamente possa solucionar o problema da pobreza. As diferenças em "eficiência" - capturadas pelo termo de erro na função fronteira de lucro - são importantes para explicar as diferenças entre os pobres e os não pobres, mas não para as demais dicotomias estudadas. Isto sugere que os fatores não observáveis - como restrições ou falhas de mercado - são importantes para explicar a pobreza entre produtores agrícolas no Brasil.
Sustentabilidade em Silvânia (GO): o caso dos assentamentos rurais São Sebastião da Garganta e João de Deus
Authors: Alves Luiz Batista , Bastos Rogério Pereira
Published: January 2012

A proposta básica do trabalho foi analisar e verificar a sustentabilidade nos assentamentos São Sebastião da Garganta (ASSG) e João de Deus (AJD) no município de Silvânia (GO). Aplicou-se questionário com variáveis socioeconômicas, ambientais e de capital social, que possibilitaram os cálculos dos respectivos índices: Índice de Desenvolvimento Socioeconômico (Idese) de 0,6779 e 0,2868; Índice Ambiental (IA) de 0,6470 e 0,2742; e Índice de Capital Social (IKS) de 0,8939 e 0,2778, que permitiram a composição pela média aritmética simples do Índice de Sustentabilidade (IS), que atingiu o valor de 0,7396 e 0,2796, respectivamente, para ASSG e AJD, caracterizando nível médio de sustentabilidade no primeiro e nível baixo de sustentabilidade no segundo. Os valores dos índices em separado indicaram que ocorreu nível médio de desenvolvimento socioeconômico, alto de capital social e médio no aspecto ambiental para o ASSG e níveis baixos de desenvolvimento socioeconômico, de capital social e no aspecto ambiental para o AJD.
Compensação e incentivo à proteção ambiental: o caso do ICMS ecológico em Minas Gerais
Authors: Fernandes Luciany Lima , Coelho Alexandre Bragança , Fernandes Elaine Aparecida , Lima João Eustáquio de
Published: January 2012

O ICMS Ecológico, criado em 1991 no Paraná, surgiu da reivindicação dos municípios que sentiam que suas economias eram prejudicadas pelas restrições de uso do solo, originadas por serem mananciais de abastecimento para municípios vizinhos ou por integrarem Unidades de Conservação. Dessa forma, o poder público estadual sentiu a necessidade de reformular os critérios de distribuição do ICMS, favorecendo estes municípios com recursos adicionais. Em Minas Gerais, o ICMS Ecológico foi criado em 1995, através da Lei Robin Hood. No sentido de verificar o impacto desse instrumento, esse artigo teve como objetivo analisá-lo nas suas funções de compensação e incentivo aos municípios mineiros. Nesse sentido, foram calculados os índices consolidados de produção e de preservação para todos os municípios mineiros, e utilizou-se um modelo de dados em painel para verificar qual a relação entre a área protegida e o valor do ICMS Ecológico recebido através do subcritério Unidades de Conservação. Os resultados obtidos mostram que esse instrumento compensa a maior parte dos municípios, mas vem perdendo sua importância nos últimos anos. Quanto ao incentivo, o ICMS Ecológico realmente incentiva a preservação e a conservação do meio ambiente, pois há uma relação direta entre o montante recebido e o crescimento de áreas protegidas nos municípios mineiros.
Determinantes da demanda brasileira por importação de arroz do Mercosul
Authors: Capitani Daniel Henrique Dario , Miranda Sílvia Helena Galvão de , Filho João Gomes Martines
Published: January 2012

Desde meados da década de 1990, o arroz é um dos principais produtos agrícolas importados pelo Brasil, principalmente do Uruguai e da Argentina, o que frequentemente gera questionamentos dos orizicultores brasileiros. O objetivo deste artigo é analisar os determinantes das importações brasileiras deste cereal, e para tanto, apresenta-se um modelo econômico visando analisar esta relação comercial no Mercosul, assumindo que as importações brasileiras de arroz são resultantes de um excesso de demanda doméstica pelo cereal. Utiliza-se um Modelo Autorregressivo Vetorial - VAR estrutural. Os resultados mostram uma forte relação do volume importado com o preço doméstico do arroz e com a taxa de câmbio. Verifica-se uma significativa participação do preço de importação na explicação do preço doméstico. A quantidade importada de arroz responde positivamente a um choque positivo no preço doméstico e negativamente a choques positivos no preço de importação e na taxa de câmbio. Verifica-se uma relação de bicausalidade entre o preço doméstico e o preço de importação de arroz. Uma das principais conclusões é que a demanda por importação reage imediatamente a choques no preço doméstico e taxa de câmbio, e posteriormente, a choques no preço de importação, sugerindo dificuldades em substituir imediatamente o volume importado no mercado doméstico.
Território café do Cerrado: transformações na estrutura produtiva e seus impactos sobre o pessoal ocupado
Authors: Ortega Antonio César , Jesus Clesio Marcelino
Published: January 2012

O desenvolvimento da agricultura brasileira ao longo do século XX e início deste século XXI provocou grandes transformações no processo produtivo de diversas cadeias agropecuárias. Neste contexto, o Cerrado Mineiro merece destaque particular, pois se consolidou como uma das regiões cafeicultoras mais modernas do país, com a adoção de um conjunto de inovações tecnológicas, cujo resultado foi a obtenção de elevada produtividade e qualidade do café. Entretanto, para se alcançar tal grau de desenvolvimento tecnológico, a estrutura produtiva passou por grandes transformações desde o início dos anos 70 até 2000, inclusive no que diz respeito às relações de trabalho. O objetivo deste artigo é apontar como se deram essas transformações, qual o impacto sobre a produção e o emprego, bem como sobre a organização dos cafeicultores em torno do fortalecimento da cadeia do café. Para alcançar esses objetivos, foi realizada revisão bibliográfica de trabalhos de especialistas da área, além da utilização de dados dos censos agropecuários de 1970 a 2006 e pesquisa de campo junto a produtores e lideranças representativas dos cafeicultores, pesquisadores agronômicos, técnicos de assistência técnica e empresas líderes na comercialização de insumos e equipamentos. Concluiu-se que o processo de modernização da atividade do café no Cerrado Mineiro provocou impactos significativos na ampliação da área produtiva, na produtividade, na geração de novos postos de trabalho em atividades mais qualificadas e redução das menos qualificadas.
Microstructural features influencing failure in Macadamia nuts
Authors: Fleck C. , Schüler P. , Meinel D. , Zaslansky P. , Currey J. D.
Published: January 2012

Macadamia nutshells exhibit surprisingly high strength making them interesting model materials for impact-resistant engineering structures. The properties of the nutshell are assumed to arise from the hierarchically organized microstructure. However, the relationship between microstructure and mechanical properties is not completely clear. We investigated the failure behavior of whole Macadamia integrifolia nutshells and specimens cut from the shell, under tension and compression loading. Deformation and fracture were observed by means of light and scanning electron microscopy and microtomography. The outer and inner sutures, the vascular bundles, and the interfaces between cells or cell bundles were shown to affect formation and growth of cracks and thereby they strongly modulate the strength. While the sutures act as weak links and notches increasing the local stresses, the vascular bundles both increase local stresses due to their notch effect, and also divert and even stop cracks. Cracks are further diverted by bundles of aligned fiber cells.
Emulsion route in fabrication of micro and nanocontainers for biomimetic self-healing and self-protecting functional coatings
Authors: Grigoriev Dmitry O. , Haase Martin F. , Fandrich Nick , Latnikova Alexandra , Shchukin Dmitry G.
Published: January 2012

Designing of novel self-healing materials possessing an active feedback on various destructive factors is one of most quickly developing areas in contemporary material engineering. Self-healing and self-protecting coatings represent one of particular classes of these materials that able on damage to recover their anticorrosive or antifouling function. Most established approach to impart to the coating this ability is nowadays the use of container-based structures when the protective agent trapped in containers is embedded in the coating matrix. There are different ways to produce containers for the further incorporation into coating but the role of emulsion route in the containers preparation is probably predominant. Herein, the contemporary achievements in the field of emulsion encapsulation are reviewed. Several types of containers for biomimetic functional coatings synthesized via emulsion as an initial system are presented based mainly on the earlier published and very recently obtained results of our research group. An overview is given of some interfacial physical and chemical methods utilized for the transformation of emulsion droplets into nano- or microscaled containers showing their specific advantages and drawbacks. Successful incorporation of containers in the diverse types of coatings showed is promising for novel materials production in many application fields.
Ecological determinism increases with organism size
Authors: Farjalla Vinicius F. , Srivastava Diane S. , Marino Nicholas A. C. , Azevedo Fernanda D. , Dib Viviane , Lopes Paloma M. , Rosado Alexandre S. , Bozelli Reinaldo L. , Esteves Francisco A.
Published: January 2012

After much debate, there is an emerging consensus that the composition of many ecological communities is determined both by species traits, as proposed by niche theory, as well as by chance events. A critical question for ecology is, therefore, which attributes of species predict the dominance of deterministic or stochastic processes. We outline two hypotheses by which organism size could determine which processes structure ecological communities, and we test these hypotheses by comparing the community structure in bromeliad phytotelmata of three groups of organisms (bacteria, zooplankton, and macroinvertebrates) that encompass a 10 000‐fold gradient in body size, but live in the same habitat. Bacteria had no habitat associations, as would be expected from trait‐neutral stochastic processes, but still showed exclusion among species pairs, as would be expected from niche‐based processes. Macroinvertebrates had strong habitat and species associations, indicating niche‐based processes. Zooplankton, with body size between bacteria and macroinvertebrates, showed intermediate habitat associations. We concluded that a key niche process, habitat filtering, strengthened with organism size, possibly because larger organisms are both less plastic in their fundamental niches and more able to be selective in dispersal. These results suggest that the relative importance of deterministic and stochastic processes may be predictable from organism size.
Sub-Chronic Oral Exposure to Iridium (III) Chloride Hydrate in Female Wistar Rats: Distribution and Excretion of the Metal
Authors: Iavicoli Ivo , Fontana Luca , Bergamaschi Antonio , Conti Marcelo Enrique , Pino Anna , Mattei Daniela , Bocca Beatrice , Alimonti Alessandro
Published: January 2012

Iridium tissue distribution and excretion in female Wistar rats following oral exposure to iridium (III) chloride hydrate in drinking water (from 1 to 1000 ng/ml) in a sub-chronic oral study were determined. Samples of urine, feces, blood and organs (kidneys, liver, lung, spleen and brain) were collected at the end of exposure. The most prominent fractions of iridium were retained in kidney and spleen; smaller amounts were found in lungs, liver and brain. Iridium brain levels were lower than those observed in other tissues but this finding can support the hypothesis of iridium capability to cross the blood brain barrier. The iridium kidney levels rose significantly with the administered dose. At the highest dose, important amounts of the metal were found in serum, urine and feces. Iridium was predominantly excreted via feces with a significant linear correlation with the ingested dose, which is likely due to low intestinal absorption of the metal. However, at the higher doses iridium was also eliminated through urine. These findings may be useful to help in the understanding of the adverse health effects, particularly on the immune system, of iridium dispersed in the environment as well as in identifying appropriate biological indices of iridium exposure.
The influence of the UV irradiation intensity on photocatalytic activity of ZnAl layered double hydroxides and derived mixed oxides
Authors: Hadnadjev-Kostic Milica , Vulic Tatjana , Zoric Dmitar , Marinkovic-Neducin Radmila
Published: January 2012

Layered double hydroxides (LDHs) have been studied to a great extent as
environmental-friendly complex materials that can be used as photocatalysts
or photocatalyst supports. ZnAl layered double hydroxides and their derived
mixed oxides were chosen for the investigation of photocatalytic performances
in correlation with the UV intensities measured in the South Pannonia region.
Low supersaturation coprecipitation method was used for the ZnAl LDH
synthesis. For the characterization of LDH and thermal treated samples powder
X-ray diffraction (XRD), scanning electron microscopy (SEM), electron
dispersive spectroscopy (EDS), nitrogen adsorption-desorption were used. The
decomposition of azodye, methylene blue was chosen as photocatalytic test
reaction. The study showed that the ZnAl mixed oxide obtained by thermal
decomposition of ZnAl LDH has stable activity in the broader UV light
irradiation range characterizing the selected region. Photocatalytic activity
could be mainly attributed to the ZnO phase, detected both in LDH and
thermally treated samples. The study showed that the ZnAl mixed oxide
obtained by the calcination of ZnAl LDH has a stable activity within the
measured UV light irradiation range; whereas the parent ZnAl LDH catalyst did
not perform satisfactory when low UV irradiation intensity is implied.
Size effects for micro-fractured bodies under compressive loading
Authors: Dobrovat A.M. , Dascalu C. , Bilbie G. , Nguyen M.T.
Published: January 2012

A two-scale damage model for micro-fractured media is constructed using the
asymptotic homogenization method. At the small-scale level, we consider
locally periodic microstructures of two-types: micro-cracks nucleating from
pores and wing-type micro-cracks. Based on an energy criterion for
micro-crack propagation we deduce the macroscopic damage model, without
supplementary assumptions on the overall behavior. We show that the resulting
two-scale model has the property of capturing a micro-structural length - the
distance between neighbor micro-cracks. The influence of the micro-structural
parameters on the effective behavior is studied. We illustrate the capacity
of the model to predict size effects under compression loadings.
Anisotropic spreading of liquid metal on a rough intermetallic surface
Authors: Liu Wen , Sekulic Dusan
Published: January 2012

An anisotropic wicking of molten Sn-Pb solder over an intermetallic rough
surface has been studied. The phenomenon features preferential spreading and
forming of an elliptical spread domain. A theoretically formulated model was
established to predict the ratio of the wicking distance along the long axis
(rx) to that along the short axis (ry) of the final wicking pattern. The
phenomenon was simultaneously experimentally observed and recorded with a
hotstage microscopy technique. The anisotropic wicking is established to be
caused by a non-uniform topography of surface micro structures as opposed to
an isotropic wicking on an intermetallic surface with uniformly distributed
surface micro features. The relative deviation between the theoretically
predicted rx/ry ratio and the corresponding average experimental value is 5%.
Hence, the small margin of error confirms the validity of the proposed
theoretical model of anisotropic wicking.
Mechanically equivalent elastic-plastic deformations and the problem of plastic spin
Authors: Steigmann David , Gupta Anurag
Published: January 2012

The problem of plastic spin is phrased in terms of a notion of mechanical
equivalence among local intermediate configurations of an elastic/ plastic
crystalline solid. This idea is used to show that, without further
qualification, the plastic spin may be suppressed at the constitutive level.
However, the spin is closely tied to an underlying undistorted crystal
lattice which, once specified, eliminates the freedom afforded by mechanical
equivalence. As a practical matter a constitutive specification of plastic
spin is therefore required. Suppression of plastic spin thus emerges as
merely one such specification among many. Restrictions on these are derived
in the case of rate-independent response.
Is Earnings Quality Associated with Corporate Social Responsibility?
Authors: Kim Yongtae , Park Myung Seok , Wier Benson
Published: January 2012

This study examines whether socially responsible firms behave differently from other firms in their financial reporting. Specifically, we question whether firms that exhibit corporate social responsibility (CSR) also behave in a responsible manner to constrain earnings management, thereby delivering more transparent and reliable financial information to investors as compared to firms that do not meet the same social criteria. We find that socially responsible firms are less likely (1) to manage earnings through discretionary accruals, (2) to manipulate real operating activities, and (3) to be the subject of SEC investigations, as evidenced by Accounting and Auditing Enforcement Releases against top executives. Our results are robust to (1) controlling for various incentives for CSR and earnings management, (2) considering various CSR dimensions and components, and (3) using alternative proxies for CSR and accruals quality. To the extent that we control for the potential effects of reputation and financial performance, our findings suggest that ethical concerns are likely to drive managers to produce high-quality financial reports.

Data Availability: Data used in this study are available from public sources identified in the study.
Commentary on Auditing High-Uncertainty Fair Value Estimates
Authors: Bell Timothy B. , Griffin Jeremy B.
Published: January 2012

This commentary addresses challenges faced by standard-setters, preparers, users, and auditors pertaining to high-uncertainty fair value estimates. We briefly describe the financial reporting environment and the difficulty of obtaining reasonable assurance for fair value estimates with high levels of inherent measurement uncertainty. We then discuss some characteristics of an effective accountability framework for fair value accounting. We propose that additional disclosures of management's historical estimation accuracy and current levels of inherent measurement uncertainty, accompanied by changes in the audit process and auditors' communications to users, offer the most practical means to address concerns about the transparency and verifiability of high-uncertainty fair value estimates.

JEL Classifications: M42; M48.
“Research Opportunities in Auditing in the EU,” Revisited
Authors: Maijoor Steven , Vanstraelen Ann
Published: January 2012

This article presents a number of research opportunities in auditing in the EU that have come along with changes in the EU regulatory framework for financial reporting and auditing during the past decade. In doing so, we build on Schilder (1996), who raised a number of key research questions, and conclude that some of those questions remain unanswered and are still relevant today. At the same time, new opportunities arise in the changed EU landscape. We identify some important areas where research can help advance our knowledge and provide relevant information for policy makers. These research areas include: public oversight, audit market concentration, audit quality, audit firm ownership structures, audit firm operating structures, audit firm governance, and auditor liability. The research questions that we raise are of global interest, but the EU market provides some unique natural experimental settings to address these questions.
Globalization and Multinational Auditing: The Case of Gazprom and PwC in Russia
Authors: Alon Anna , Dwyer Peggy D.
Published: January 2012

We examine the role of auditing in developing markets. Our purpose is to gain insight into social expectations for the audit function and the nature of the auditor/client relationship in Russia. Conceptually we rely on two related theoretical sources. First we draw on Giddens' theorizing with regard to the process of globalization. We also draw conceptual insight from sociologically informed research on the evolved institutional role of the multinational audit firms. Against that theoretical framework, we conduct a qualitative empirical analysis based on the case of the PricewaterhouseCoopers' audits of the Russian gas giant OAO Gazprom. Three controversial episodes were analyzed using accounts from the international media and the local, Russian-language, media. In general, the international media accounts express their expectations for auditing by reference to functionalist accounting and concepts, such as auditor objectivity, disclosure of related party transactions, and unrestricted audit scope. In contrast, local media accounts express expectations for auditing that are more generally nationalist. Local media accounts often focused on themes relating to Russian national prestige, treated the presence of non-arms-length transactions as unexceptional, and revealed perceptions that Western style auditing approaches may not be appropriate in the Russian context. We interpret the data in light of the theoretical framework, prior literature, and the contradictory expectations revealed in the analysis of media accounts. The study adds insight regarding the possibility of universal, global norms and standards for accounting and auditing.
Responding to the Leadership Needs of the Accounting Profession: A Module for Developing a Leadership Mindset in Accounting Students
Authors: Bloch Janel , Brewer Peter C. , Stout David E.
Published: January 2012

Surveys of practitioners point to the importance of leadership skills in the accounting profession. However, leadership is not currently emphasized much within accounting curricula. Further, a review of the accounting education literature indicates a lack of instructional resources for accounting faculty desiring to help students develop leadership skills. As a result, accounting students may graduate without the mindset required to think of themselves as potential leaders. Therefore, there are opportunities to add value to accounting curricula by intervening in the area of leadership development. This article describes one such intervention that can be used as part of a comprehensive approach to leadership development. The primary goal of this three-week module is modest but important: to help instill a leadership mindset in accounting students. The class-tested module consists of targeted cases and supplementary readings covering six primary leadership topics. These topics were selected to build upon leadership material covered in a basic management course. While the module was used in undergraduate cost accounting, it (or a suitably reduced version of it) is appropriate for use in other accounting courses, particularly upper-level courses. This article offers implementation guidance and resources for the accounting instructor, including access to electronic files that can be used to teach the module. Assessment data from the students who recently completed this module indicate that they viewed the module as a beneficial learning experience.
Retinal Vascular Geometry Predicts Incident Renal Dysfunction in Young People With Type 1 Diabetes
Authors: Benitez-Aguirre Paul Z. , Sasongko Muhammad Bayu , Craig Maria E. , Jenkins Alicia J. , Cusumano Janine , Cheung Ning , Wong Tien Yin , Donaghue Kim C.
Published: January 2012

OBJECTIVE

To examine the relationship between retinal vascular geometry parameters and development of incident renal dysfunction in young people with type 1 diabetes.

RESEARCH DESIGN AND METHODS

This was a prospective cohort study of 511 adolescents with type 1 diabetes of at least 2 years duration, with normal albumin excretion rate (AER) and no retinopathy at baseline while attending an Australian tertiary-care hospital. AER was quantified using three overnight, timed urine specimen collections and early renal dysfunction was defined as AER >7.5 μg/min. Retinal vascular geometry (including length-to-diameter ratio [LDR] and simple tortuosity [ST]) was quantified from baseline retinal photographs. Generalized estimating equations were used to examine the relationship between incident renal dysfunction and baseline venular LDR and ST, adjusting for age, diabetes duration, glycated hemoglobin (A1C), blood pressure (BP), BMI, and cholesterol.

RESULTS

Diabetes duration at baseline was 4.8 (IQR 3.3–7.5) years. After a median 3.7 (2.3–5.7) years follow-up, 34% of participants developed incident renal dysfunction. In multivariate analysis, higher retinal venular LDR (odds ratio 1.7, 95% CI 1.2–2.4; quartile 4 vs. 1–3) and lower venular ST (1.6, 1.1–2.2; quartile 1 vs. 2–4) predicted incident renal dysfunction.

CONCLUSIONS

Retinal venular geometry independently predicted incident renal dysfunction in young people with type 1 diabetes. These noninvasive retinal measures may help to elucidate early mechanistic pathways for microvascular complications. Retinal venular geometry may be a useful tool to identify individuals at high risk of renal disease early in the course of diabetes.
Integrated Multimodel Evaluation of Transit Bus Emissions in Toronto, Canada
Authors: Lau Judith , Hatzopoulou Marianne , Wahba Mohamed M. , Miller Eric J.
Published: January 2012

This paper investigates transit bus emissions in the city of Toronto, Ontario, Canada, by linking the results of a microsimulation transit assignment model, MILATRAS (microsimulation learning-based approach to transit assignment), with emission factors derived from Mobile6.2C. Emissions were estimated at the level of individual buses during idling conditions at bus stops and on roadway links between stops during the morning peak period. The busiest routes were associated with the highest total emissions as a result of a combination of high ridership and lower speeds; this association confirmed the common wisdom that newer, low-emitting buses should be first allocated to these routes. The highest dwell emissions occurred at intermodal transfer stations (bus to subway and vice versa). On a passenger kilometer basis, the highest-emitting routes were not the busiest, but rather were those with the lowest ridership. In fact, the highest emissions per passenger kilometer were associated with the Airport Rocket, a route that provided service to the airport and was characterized by low ridership in the morning peak period. On average, bus trips in Toronto were about three times more fuel efficient than were private car trips and created 20 times less carbon monoxide pollution. The effects of changing fuel types and fleet age on transit bus emissions were assessed. Implications for bus operations are discussed relative to fleet allocation to minimize total emissions.
Development of Key Performance Indicator to Compare Regularity of Service between Urban Bus Operators
Authors: Trompet Mark , Liu Xiang , Graham Daniel J.
Published: January 2012

This paper evaluates options for a key performance indicator that compares differences in performance for maintaining service regularity on high-frequency routes between urban bus operators. The data used for this study were collected by the International Bus Benchmarking Group, facilitated by Imperial College London, and relate to 12 medium- to large-sized urban bus operators from different countries. Two annual rounds of data collection provided lessons on feasible data characteristics, required sample size, and data-cleaning processes. Four key performance indicator alternatives were tested. Their strengths and weaknesses are described: excess wait time; standard deviation of the difference between the scheduled and the actual headway, and two methods that show percentages of service within a fixed (wait assessment) and a relative (service reliability) number of minutes from the scheduled headway. The results suggest that whereas all four methodologies illustrate a different, interesting view on service regularity performance, the methodology for excess wait time is the best option when the key performance indicator should reflect the customer experience of the regularity of service.
Impacts of Holding Control Strategies on Transit Performance
Authors: Cats Oded , Larijani Anahid Nabavi , Koutsopoulos Haris N. , Burghout Wilco
Published: January 2012

Transit operators are interested in strategies to improve service reliability as it is an important measure of performance and level of service. One of the common practices aimed at reducing service unreliability is holding control strategies. The design of these strategies involves the selection of a set of time point stops and the holding criteria for regulating the departure time. The interactions between passenger activity, transit operations, and traffic dynamics must be dynamically modeled to analyze the impacts of holding strategies on transit performance. An evaluation of different holding criteria and the number and location of time point stops was conducted with BusMezzo, a dynamic transit simulation model. The holding strategies were implemented in the model and applied to a high-frequency trunk bus line in Stockholm, Sweden. The analysis of the results considers the implications of holding strategies from both passenger and operator perspectives. The analysis suggests substantial gains are possible by implementing a holding strategy on the basis of the mean headway from the preceding and the succeeding buses. This strategy is the most efficient for passenger time savings as well as fleet costs and crew management.
Measuring and Controlling Subway Fare Evasion
Authors: Reddy Alla V. , Kuhls Jacqueline , Lu Alex
Published: January 2012

New York City Transit (NYCT) has a comprehensive framework for assessing, managing, and combating subway fare evasion. The automated fare collection system, implemented between 1994 and 1997, features lessons learned from field trials of prototypes specifically designed to limit fare abuse. Subway crime has decreased 68% since 2000, and the annual average subway evasion rate remains low at approximately 1.3%. Today, the transit authority measures fare evasion with independent silent observers who use stratified random sampling techniques and classify passenger entries into 19 categories. Evasion rates peak at 3 p.m., when students are dismissed, but otherwise hover around 0.9% at peak and 1.9% at off-peak hours. Busy times and locations have higher evasions per hour but lower evasions per passenger. More evasions occur in lower-income neighborhoods. Staff presence apparently does not reduce evasions. Results are released to the press on request, which promotes transparency and accountability. As an evasion deterrent, NYCT increased fines from $60 to $100 in 2008. Police issued 68,000 summonses and made 19,000 evasion arrests in 2009. Arrests are a more effective deterrent than summonses; the proportion of arrests versus summonses increased in 2010. Video monitoring equipment is used to identify and apprehend chronic fare abusers, particularly swipers who sell subway entries by abusing unlimited fare media.
Resiliency of Transportation Network of Santo Domingo, Dominican Republic
Authors: Serulle Nayel Urena , Heaslip Kevin , Brady Brandon , Louisell William C. , Collura John
Published: January 2012

Every day dependence on transportation grows as local, regional, national, and international independence increases. Resilient transportation systems are needed to secure the highest possible level of service during disruptive events, including natural disasters and those caused by humans. To prepare for these events, decision makers need guidance to determine what investments are likely to improve the resiliency of their networks, which are often hampered by limited resources. To date, such guidance has been primarily qualitative. This paper presents a methodology to quantify resiliency, under preevent conditions, by use of a fuzzy inference approach. This methodology expands on previous work by the authors and others, by refining the definitions of key variables, adjusting model interactions, and increasing transparency between metrics. The paper includes a case study in which the methodology is applied to a disruptive event in Santo Domingo, Dominican Republic. The case study illustrates the methodology's ability to (a) evaluate the extent to which the Dominican Republic's transportation network is prepared for a disruptive event, (b) help select investments that have the potential to increase the resiliency of the network, and (c) provide outputs that will support a variety of current economic analysis strategies, allow comparison of different investment scenarios, and facilitate decision making. The paper concludes with a sensitivity analysis that shows the effects of alternative investments on the network.