bluuebunny/crossref_metadata_2025 huggingface dataset:
A estrutura de capital das maiores empresas brasileiras: análise empírica das teorias de Pecking Order e trade-off, usando panel data
Authors: Correa Carlos Alberto , Basso Leonardo Fernando Cruz , Nakamura Wilson Toshiro
Published: September 2013

Pesquisas sobre estrutura de capital das empresas são consideradas dentre as mais relevantes na área de finanças. Diversas abordagens teóricas têm sido discutidas e testadas na literatura financeira. Este estudo buscou analisar o nível de endividamento das maiores empresas brasileiras, à luz das duas principais teorias que versam sobre o assunto, a teoria de Pecking Order e a teoria de trade-off, testando seus determinantes. A teoria do Pecking Order sugere a existência de uma hierarquia no uso de fontes de recursos, enquanto a teoria de trade-off considera a existência de uma estrutura meta de capital que seria perseguida pela empresa. O estudo é uma adaptação do artigo de Gaud et al. (2005), cujo trabalho serviu como base e principal referência para a escolha das principais variáveis e dos testes econométricos realizados. Tal como Gaud et al. (2005), desenvolvemos as análises estatísticas utilizando a metodologia de Panel Data, que considera os dados da amostra em corte transversal e longitudinal. Além de testes estáticos, foram feitos testes dinâmicos, com o objetivo de analisar o processo de ajuste da estrutura de capital ao longo do tempo, em direção a um suposto nível-alvo ótimo. Os resultados demonstraram relação negativa entre o nível de endividamento das empresas e o grau de tangibilidade dos ativos e a rentabilidade, bem como relação positiva do endividamento com o risco. Demonstraram ainda que empresas de capital estrangeiro são mais endividadas que empresas nacionais. De um modo geral, os resultados sugerem que a teoria de Pecking Order é mais consistente do que a teoria de trade-off para explicar a estrutura de capital das companhias abertas brasileiras. Em especial, destacamos a relação negativa entre endividamento e rentabilidade, confirmando vários outros resultados de pesquisa obtidos na realidade brasileira. A análise dinâmica demonstrou baixa velocidade do processo de ajuste da estrutura de capital em direção ao nível-alvo, sugerindo a existência de elevados custos de transação e confirmando o comportamento de Pecking Order dos administradores.
O problema da análise em pesquisa cartográfica
Authors: Barros Letícia Maria Renault de , Barros Maria Elizabeth Barros de
Published: September 2013

Este artigo aborda o papel da análise em uma pesquisa de abordagem cartográfica. Ao equivocar a noção de "dado", entendemos que a análise em cartografia leva a uma redefinição das fronteiras entre subjetividade e objetividade. A análise em cartografia está afinada com outras abordagens de pesquisa e intervenção, assumindo diferentes procedimentos que permitem a análise de implicação na pesquisa e, por conseguinte, a análise da participação. Como efeito da análise, há o reposicionamento do lugar dos participantes na pesquisa. A análise em cartografia permite, ao longo de toda a realização da pesquisa, o acesso a uma objetividade que, em lugar de fixar um sentido unívoco, tende a proliferar sentidos. A cartografia afirma tal paradoxo por meio de uma atitude analítica, agente de singularização.
Use of artificial sediment to assess toxicity of chromium on Chironomus xanthus, Danio rerio and Poecilia reticulata
Authors: Campagna Aline Fernanda , Rodrigues Beatriz Kawamura , Nogueirol Roberta Corrêa , Verani Nelsy Fenerich , Espíndola Evaldo Luiz Gaeta , Alleoni Luís Reynaldo Ferracciú
Published: September 2013

AIM: Artificial sediments with simple formulations were used to assess the toxicity of Cr to C. xanthus, D. rerio and P. reticulata. METHODS: The organisms were exposed to two sediment formulations: one without organic matter (S0) and one with 1% organic matter (SIII), both contaminated with Cr at concentrations of 90, 180, 360, 720 and 1440 mg/kg for the assays with C. xanthus, and 375, 750, 1500 and 3000 mg/kg for those with the two fish species. Chromium was obtained from the potassium dichromate (K2Cr2O7). RESULTS: The results of the acute toxicity tests demonstrated a reduction of up to four times in toxicity with the presence of OM, consisting of biodegradable detritus, even at the low concentration used (1%), and that C. xanthus was most sensitive to the metal. The reduction in the chromium toxicity was indicated by the LC50 values, which were higher in SIII (1234.43 mg/kg; 2263.54 m/kg; 2244.48 mg/kg) than in S0 (340.56 mg/kg; 1731.04 mg/kg; 1733.55 mg/kg) for C. xanthus, D. rerio and P. reticulata, respectively. CONCLUSIONS: Because of the repeatability of the results obtained, the artificial sediments with simple formulations were satisfactory to assess toxicity and can thus provide reliable results in ecotoxicological studies
Geographic Differentiation of ColombianNeoleucinodes elegantalis(Lepidoptera: Crambidae) Haplotypes: Evidence for Solanaceae Host Plant Association and Holdridge Life Zones for Genetic Differentiation
Authors: Díaz-Montilla A E , Suárez-Baron H G , Gallego-Sánchez G , Saldamando—Benjumea C I , Tohme J
Published: September 2013

The purpose of this study was to examine the population structure of Neoleucinodes elegantalis (Guenée) (Lepidoptera: Crambidae) in relation to host plant association and ecological Holdridge zones. Adult collections were made in cultivated and wild Solanaceae species in 13 departments of Colombia. Sequencing of 658 bp of the mitochondrial gene Cytochrome Oxidase 1 on 103 individuals produced 25 haplotypes. Haplotypes Hl, H2, H4, and H7 were the most frequent and were geographically separated by the Andean mountains. We obtained an FST = 0.57 (P < 0.0001), where most of the genetic differentiation (42.64%) was between individuals within each department. Pairwise FST analysis produced higher genetic values between geographically separated departments than between closely related sites. H2 and H7 apparently behave as generalist populations, as they were found in different habitats and different hosts. The most divergent populations of N. elegantalis were found in southern Colombia, at a location were Solanun quitoense might have originated. Host plant association and environmental factors such as Holdridge life zones are playing an important role in the differentiation of N.elegantalis. Population structuring in N.elegantalis indicates that integrated pest management strategies used to control this species should consider the genetic differentiation of the species at different locations in Colombia.
Host Plant Effects on the Development, Survival, and Reproduction ofDysmicoccus brevipes(Hemiptera: Pseudococcidae) on Grapevines
Authors: Bertin A , Bortoli L C , Botton M , Parra JRP
Published: September 2013

Dysmicoccus brevipes (Cockerell, 1893) (Hemiptera: Pseudococcidae) is one of the most frequent and abundant mealybugs in Brazilian vineyards, where it causes direct and indirect damage to the vines. In this study, we investigated the effect of plant structures, cultivars, and vine rootstocks on the development, survival, and reproduction of D. brevipes under laboratory conditions. Leaves of the tablegrape cultivar’ ‘Itália’ (Vitis vinifera) and ‘Niágara Rosada’ (Vitis labrusca) and the vine roots of the rootstocks Paulsen 1103 (Vitis berlandieri × V. rupestris) and IAC 572 (Vitis caribaea × 101-14 Mgt) were used as host plants. D. brevipes developed on different vegetative structures, cultivars, and vine rootstocks. D. brevipes showed the shortest developmental period and highest survival and fecundity rates on leaves of cultivar Itália. Survival on leaves was significantly higher than on roots. Roots of IAC 572 were unsuitable for D. brevipes development, resulting in nonreproductive females. The mealybugs’ longevity on leaves and vine roots was similar. Higher intrinsic and finite rates of increase and net reproductive rate were observed when mealybugs developed on Itália leaves. We concluded that the host plant affects the development and survival of D. brevipes and that the choice of the most appropriate cultivar or vine rootstock can help to reduce pest infestation, and is therefore an additional component to be included in the integrated pest management of grapes.
Morphological and Molecular Characterization of the Eggs of Some Noctuid Species Associated with Soybean in Brazil
Authors: Rolim Adrian Augusto Sosa Gomez , Yano Silvia Akimi Cavaguchi , Specht Alexandre , Andrade Celia Guadalupe Tardelli De Jesus , Sosa-Gómez Daniel Ricardo
Published: September 2013

The most important species of Lepidoptera that attack soybean, in descending order of importance, are Chrysodeixis includens (Walker), Anticarsia gemmatalis Hübner, Spodoptera cosmioides (Walker), Spodoptera eridania (Stoll), and Spodoptera albula (Walker). In addition, Rachiplusia nu ( Guenée ) is one of the most common Plusiinae in the southern region of Brazil, encompassing the states of Paraná, Santa Catalina, and Rio Grande do Sul. The correct identification of these species is essential for choosing the appropriate control measures, as they differ in their susceptibility to insecticides and biological control agents. To distinguish Lepidoptera species commonly found in Brazil, the eggshells of all these species were morphologically characterized by scanning electron microscopy. Diagnostic characters for differentiating species include shape of rosette petals, number of primary cells, number of secondary cells, number of ribs, and rosette diameter. Also, a molecular diagnostic method using polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP) analysis was developed to distinguish noctuid species commonly found in Brazil. A 658-bp region of the mitochondrial DNA cytochrome oxidase subunit I gene was amplified using PCR and then sequenced. The five Lepidoptera species were distinguished by restriction enzymes Bpm I and Mbol. RFLPs produced by Bpm I endonuclease were useful to discriminate species from within Spodoptera (S. cosmioides, S. eridania, and S. albula) and R. nu from C. includens. However, Bpm I did not digest the amplicons from S. eridania and C. includens, which were discriminated by RFLP patterns produced by the restriction enzyme MboI. PCR-RFLP can be performed in a short period, and it is useful to distinguish the most important Brazilian Lepidoptera soybean pests.
Spatial occupancy models applied to atlas data show Southern Ground Hornbills strongly depend on protected areas
Authors: Broms Kristin M. , Johnson Devin S. , Altwegg Res , Conquest Loveday L.
Published: September 2013

Determining the range of a species and exploring species–habitat associations are central questions in ecology and can be answered by analyzing presence–absence data. Often, both the sampling of sites and the desired area of inference involve neighboring sites; thus, positive spatial autocorrelation between these sites is expected. Using survey data for the Southern Ground Hornbill (Bucorvus leadbeateri) from the Southern African Bird Atlas Project, we compared advantages and disadvantages of three increasingly complex models for species occupancy: an occupancy model that accounted for nondetection but assumed all sites were independent, and two spatial occupancy models that accounted for both nondetection and spatial autocorrelation. We modeled the spatial autocorrelation with an intrinsic conditional autoregressive (ICAR) model and with a restricted spatial regression (RSR) model. Both spatial models can readily be applied to any other gridded, presence–absence data set using a newly introduced R package.

The RSR model provided the best inference and was able to capture small‐scale variation that the other models did not. It showed that ground hornbills are strongly dependent on protected areas in the north of their South African range, but less so further south. The ICAR models did not capture any spatial autocorrelation in the data, and they took an order of magnitude longer than the RSR models to run. Thus, the RSR occupancy model appears to be an attractive choice for modeling occurrences at large spatial domains, while accounting for imperfect detection and spatial autocorrelation.
Local adaptation of stream communities to intraspecific variation in a terrestrial ecosystem subsidy
Authors: Jackrel Sara L. , Wootton J. Timothy
Published: September 2013

Cross‐ecosystem fluxes can intertwine otherwise disparate food webs, but the effects of biodiversity at the genotypic level on fluxes across ecosystems boundaries is not known. Fresh leaves, which vary in traits such as defensive compounds against terrestrial herbivores, drop off trees and enter streams, providing a vital resource for riverine organisms. We demonstrate substantial variation in decomposition rates among individual trees in four different rivers in the Olympic Peninsula of Washington State, USA. We show that locally derived red alder leaf litter decomposes on average 24% faster than red alder leaf litter introduced from other riparian zones. Within rivers, leaves downstream of their parent trees decompose nearly as quickly as leaves from local trees. Leaves upstream of the parent tree decomposed as slowly as leaves from trees growing alongside different rivers. Over time, aquatic decomposer communities have locally adapted to the specific trees supplying the riparian subsidies. In energy‐limited environments, such as small shaded streams, consumers must be efficient foragers. Our results indicate that this pressure for efficiency has led to adaptation at a particularly fine scale. More broadly, these results illustrate how genetic diversity and the effects of selection in one ecosystem can indirectly shape the structure of other ecosystems through ecological fluxes across boundaries.
Using watershed function as the leading indicator for water quality
Authors: Aron Joan L. , Hall Robert K. , Philbin Michael J. , Schafer Robin J.
Published: September 2013

Diffuse nonpoint source (NPS) pollutants, such as sediment, nitrogen, phosphorus, and pathogens, have become the primary cause of water quality impairments in the United States of America. Resource management agencies in the USA are expanding the use of tools for the assessment of ecosystem function in water quality programs to control NPS pollution to meet US Clean Water Act objectives. Assessing the ecosystem function of upland and riparian areas provides the context for monitoring data that can improve the targeting of best management practices for NPS pollution, and be a leading (early) indicator for more timely decisions about aquatic habitat and water quality. Assessment of watershed function can be applied to prioritizing resources, developing indicators, monitoring aquatic habitat and water quality, and implementing adaptive management plans to restore degraded ecosystems that are producing NPS pollution. This paper presents three examples of progress in the institutionalization of this approach to water quality programs for sustainable and healthy watersheds that affect federal, state, tribal, and private landowners. Future work should refine the approach by evaluating the benefits, costs, and effectiveness of the use of watershed function in water quality programs.
Using modeling to inform patient-centered care choices at the end of life
Authors: Hajizadeh Negin , Crothers Kristina , Braithwaite R Scott
Published: September 2013

Aim:
Advance directives are often under-informed due to a lack of disease-specific prognostic information. Without well-informed advance directives patients may receive default care that is incongruent with their preferences. We aimed to further inform advance care planning in patients with severe chronic obstructive pulmonary disease by estimating outcomes with alternative advance directives.
Methods:
We designed a Markov microsimulation model estimating outcomes for patients choosing between the Full Code advance directive (permitting invasive mechanical ventilation), and the Do Not Intubate directive (only permitting noninvasive ventilation).
Results:
Our model estimates Full Code patients have marginally increased one-year survival after admission for severe respiratory failure, but are more likely to be residing in a nursing home and have frequent rehospitalizations for respiratory failure.
Conclusion:
Patients with severe chronic obstructive pulmonary disease may consider these potential tradeoffs between survival, rehospitalizations and institutionalization when making informed advance care plans and end-of-life decisions. We highlight outcomes research needs for variables most influential to the model‘s outcomes, including the risk of complications of invasive mechanical ventilation and failing noninvasive mechanical ventilation.
Interview: A private sector life in comparative effectiveness research
Authors: Dubois Robert W
Published: September 2013

Robert W Dubois
joined the National Pharmaceutical Council (Washington, DC, USA) in October 2010 as its Chief Science Officer. In this role, he oversees the National Pharmaceutical Council‘s research on policy issues related to comparative effectiveness research, as well as on how health outcomes are valued. Dr Dubois has cofounded and led various healthcare research organizations in developing quality research with practical application. Throughout his career, Dr Dubois‘ primary interest has centered on defining ‘what works‘ in healthcare and finding ways for that evidence to inform healthcare decision-making. He is a recognized expert in the areas of defining best practice, disease management and appropriateness of care. He has authored more than 100 peer-reviewed articles on comparative effectiveness, evidence-based medicine, the development of practice guidelines and determining the optimal use of high-cost medical services. Dr Dubois received his AB from Harvard College (MA, USA), his MD from the Johns Hopkins School of Medicine (MD, USA) and his PhD in Health Policy from the RAND Graduate School (CA, USA). In addition, he is the associate editor of the
Journal of Comparative Effectiveness Research
and is on the editorial board for
Health Affairs
.
Developing Autobiographical Accounts as a Starting Point in Research
Authors: Sancho Juana M. , Hernández-Hernández Fernando
Published: September 2013

Teaching and research are an academic's two main responsibilities. The performance of these two roles (teacher and researcher) can be clearly separated or noticeably interwoven in a continuous reflective process that shares and interchanges positionalities and references. Research projects, in the context of the quality research group ESBRINA — contemporary subjectivities and learning environments (2009SGR 0503) — are usually started by making explicit the group's personal viewpoints regarding the topic they are scrutinising. As a result, different autobiographical accounts have been developed which provide complex and in-depth explanations of the process of constructing the research topics and relationships that are delved into. This article starts by offering a context for the research group's epistemological frame and argues for the need to conduct autobiographical accounts as a research strategy. This approach is illustrated by looking into the narratives recently written for two research, development and innovation projects. The first one was aimed at understanding how novice teachers are learning to become teachers under post-Fordist working conditions, and the second endeavoured to explore how teenagers are learning from multiple literacies inside and outside of school. The article concludes by pointing out the European dimension of the research and the lessons learnt regarding the dilemmas on writing autobiographical accounts as part of a research process. ( http://www.cecace.org/ ), coordinator of Innovative University Teaching Group — Indaga-t ( http://fint.doe.d5.ub.es/indagat-web/ ), and a member of REUNI+D — University Network for Educational Research and Innovation (EDU2010-12194-E) ( http://reunid.eu ). He has extensive experience in promoting research policy at an institutional level, advising research programmes and projects, and assessing and managing research projects. He co-directs the book series ‘Repensar la educatión [Rethinking education]’ and directs the book series ‘Intersecciones [Intersections]’ both published by Octaedro. He has published a large number of books and articles both nationally and internationally. His research focuses on emerging subjectivities, visual culture and educational innovation and improvement.
Using a Process of Collective Biography Writing in Higher Education to Develop an Ability to Explore, Reveal and Critically Reflect
Authors: Wihlborg Monne
Published: September 2013

Teaching and learning are frequently treated as processes that are separate from each other, while teachers and learners are considered as disembodied entities with a neutral position towards the content which is negotiated. In collective biography writing (CBW), a very different approach is taken. Writing, reading and learning are seen as an integrated whole, where teachers and educators and students participate in the same practice(s) and context(s), thus learning through a collaborative approach, with a particular focus on themselves as learners (teachers as well as students). In this article, a memory story example is used to show the process of being a subject and of being subjected in a social context. The example provides opportunities to become aware of how social forces work when the individual is socially approved and positioned. It is argued that the use of CBW as a methodological tool, informed by post-structural theory, is useful in learning processes that aim at revealing underlying social forces. The method supports critical reflection and opens up space for becoming more aware of differences and the construction of our ‘selving’.
Classroom Management: What Does Research Tell Us?
Authors: Postholm May Britt
Published: September 2013

The article reviews studies that focus on classroom management. The aim of classroom management is twofold. The first is to establish a quiet and calm environment in the classroom so that the pupils can take part in meaningful learning in a subject. The second aim is that classroom management contributes to the pupils' social and moral development. During an early phase, classroom management focused on pupil behaviour and discipline, and was rooted in a behaviourist understanding. This article shows that classroom management is now more about understanding the class as a social system. The findings show that several factors and conditions influence classroom management: the self-understanding of teachers and their mindfulness, the multicultural classroom, behaviour management, lack of knowledge on classroom management, knowledge of physical and social context, rules, relations and commitment, person-centred versus teacher-centred classroom management, an ecological perspective on classroom management and classroom management in connection with motivation and learning. The review article states that classroom management is just as much about managing learning processes when an activity is taking place as it is about creating peace and quiet so pupils can get down to work.
An Exploratory Study of the Online Learning Environment
Authors: Khanlarian Cynthia J. , Singh Rahul
Published: September 2013

Web-based homework (WBH) is an increasingly important phenomenon. There is little research about its character, the nature of its impact on student performance, and how that impact evolves over an academic term. The primary research questions addressed in this study are: What relevant factors in a WBH learning environment impact students' performance? And how does the impact of these factors change over the course of an academic term? This paper examines and identifies significant factors in a WBH learning environment and how they impact student performance. We studied over 300 students using WBH extensively for their coursework, throughout a semester in an undergraduate class at a large public university. In this paper, we present factors in the WBH learning environment that were found to have a significant impact on student performance during the course of a semester. In addition to individual and technological factors, this study presents findings that demonstrate that frustration with IT use is a component of the learning environment, and as a construct, has a larger impact than usefulness on student performance at the end of a course. Our results indicate that educators may benefit from training students and engaging them in utility of co-operative learning assignments to mitigate the level of frustration with the software in the WBH learning environment and improve student performance.
Effects of vermilion height on lip esthetics in Japanese and Korean orthodontists and orthodontic patients
Authors: Ioi Hideki , Kang Sangwook , Shimomura Takahiro , Kim Seong-sik , Park Soo-byung , Son Woo-sung , Takahashi Ichiro
Published: September 2013

Objective:

To evaluate the influence of vermilion height on the assessment of lip attractiveness by Japanese and Korean orthodontists and orthodontic patients.

Materials and Methods:

Vermilion heights were modified by increasing or decreasing the vermilion height in 1.0-mm increments from −3.0 mm to 3.0 mm with reference to an average vermilion height. Participants ranged from 15 to 29 years of age and comprised 29 Japanese and 25 Korean orthodontists and 96 Japanese and 72 Korean orthodontic patients. They all rated the attractiveness of seven images with altered vermilion height using a visual analog scale.

Results:

Across the participant groups, there were significant differences in the median esthetic scores for the seven vermilion height levels tested. The Japanese and Korean raters assigned the highest scores to the average vermilion height and assigned the lowest scores to the +3-mm increased vermilion height. The ranges of vermilion height preferred by orthodontists were found to be within the ranges preferred by orthodontic patients when evaluating the preferences in lip esthetics by country.

Conclusions:

We conclude that the −1-mm to +1-mm range for the average vermilion height is considered attractive for lips for both Japanese and Korean people.
Peripheral Insertion of Umbilical Cord
Authors: Luo Guangju , Redline Raymond W.
Published: September 2013

Numerous studies have addressed the significance of marginal and membranous umbilical cord (UC) insertion. Recent reports suggest that an eccentrically inserted UC may also be important. This case-control study assessed the potential relevance of peripheral insertion of UC (PIUC), defined as <3 cm from the nearest margin. Singleton placentas (n = 1418) submitted to the pathology department over an 18-month period were analyzed. Each case of PIUC (n = 119) was matched with a control placenta of the same gestational age. Placentas with marginal or membranous UC and multiple gestations were excluded. The overall prevalence of PIUC was 8.4%, but PIUC frequency was significantly increased in premature births at <28 weeks (21.4%, P < 0.001). There was no association with other adverse pregnancy outcomes. PIUC was associated with decreased placental weight Z-score (−0.69 ± 0.92 versus −0.22 ± 1.3, P = 0.0056), but not fetal weight Z-score, suggesting increased utilization of placental reserve. PIUC was also associated with relatively elongated placentas (length minus width: 2.6 ± 3.2 versus 1.0 ± 3.1, P = 0.006). PIUC tended to be more frequent in young primiparous mothers and was significantly less common in women with a history of prior curettage (66% vs 50%, P = 0.013). These data, together with equivalent rates of prior cesarean section, multiparity, and advanced maternal age, support a primary developmental disorder as opposed to secondary placental migration due to underlying uterine abnormalities (“trophotropism”). Except for a borderline significant association with findings suggestive of maternal malperfusion ( P = 0.078), PIUC was not associated with other placental lesions.
Applicability of Park transformation for the analysis of transient performance during subsynchronous resonances
Authors: Kreischer Christian , Kulig Stefan , Göbel Carsten
Published: September 2013

Long transmission lines have to be compensated to enhance the transport of active power. But a wrong design of the compensation may lead to subsynchronous resonances (SSR). For studies often park equivalent circuits are used. The parameters of the models are often determined analytically or by a three-phase short-circuit test. Models with this parameters give good results for frequencies of 50 Hz and 100 Hz resp. 60 Hz and 120 Hz. But SSR occurs at lower frequencies what arises the question of the reliability of the used models. Therefore in this publication a novel method for the determination of Park equivalent circuit parameters is presented. Herein the parameters are determined form time functions of the currents and the electromagnetic moment of the machine calculated by transient finite-element simulations. This parameters are used for network simulations and compared with the finite-element calculations. Compared to the parameters derived by a three-phase short-circuit a significant better accuracy of simulation results can be achieved by the presented method.
Temperature distribution in multi domain construction of the permanent magnet linear actuator
Authors: Tomczuk Bronisław , Waindok Andrzej
Published: September 2013

The transient thermal model of the permanent magnet linear actuator (PMLA) has been considered. The characteristics of heating have been calculated including the main subdomains of the actuator. The carcasses from various materials have also been considered. The calculations have been verified experimentally and a good conformity was obtained.
Effect of minimum energy control on steel loss in VR stepper motor
Authors: Bernat Jakub , Kołota Jakub , Stępień Sławomir
Published: September 2013

This research presents a 3D FE method for the simulation of the variable reluctance stepper motor dynamics. The proposed model is used to obtain the optimal minimum energy control law that minimizes the energy injected by the controller. The method is based on the strong coupling of field - circuit equations and extended to eddy current, motion and nonlinearity problem. The linearization technique for the coupled problem is presented. Also the lamination of the motor core is considered. In the paper the open - loop control problem is analyzed. The proposed model is validated by the comparison with measurements. Next, to demonstrate the effectiveness of the proposed optimal minimum energy control method is applied. In both cases, the examination of the variable reluctance stepper motor dynamics and the steel loss in the core is presented and compared
Analysis of instantaneous power components of electric circuit with a semiconductor element
Authors: Zagirnyak M. , Kalinov A. , Maliakova M.
Published: September 2013

Both a classical instantaneous power method and a method based on equations of instantaneous power orthogonal components balance have been used to analyze power processes in electric circuits with semiconductor elements. Automated method of forming instantaneous power harmonic components was used to obtain analytical expressions and numerical values of instantaneous power components of analyzed electric circuits. A coefficient for estimation of a semiconductor converter nonlinearity degree has been offered.
Position control of DC motor using fractional order controller
Authors: Ruszewski Andrzej , Sobolewski Andrzej
Published: September 2013

The paper presents the problem of position control of DC motor with rated voltage 24 V loaded by flywheel. The fractional order PD controller implemented in National Instruments NI ELVIS II programmed in LabView is used for controlling. The simple method for determining stability regions in the controller parameters space is given. Knowledge of these regions permits tuning of the controller and ensures required the phase margin of the system
What Do We Know about the Internationalization of Central and Eastern European Countries and Firms?
Authors: Wiliński Witold
Published: September 2013

This article is the first comprehensive literature review concerning the internationalization of countries and firms from Central and Eastern European countries (CEECs). The study covers 42articles published during the years 1989-2010, both in leading world journals on international business and management and in regional journals concentrating on the CEECs. The purpose of the study is classification of the research topics undertaken, defining the differences in internationalization between CEECs, and verification whether the studies on outward FDI from CEECs has made an important contribution to international business theory.
Active Labour Market Programmes in Poland Between 2005 and 2010
Authors: Kwiatkowska Walentyna
Published: September 2013

High unemployment in Poland is a major socio-economic problem. The unemployment rate in Poland reached the level of 16.7% in 2005, 9.3% in 2010 and 9.7% in 2011. Unemployment in Poland is mainly structural, which is reflected in the structural imbalances between labour demand and labour supply with respect to vocational qualifications, professions, and spatial deployment. The main factor determining unemployment is the necessity for structural changes in the Polish economy caused by its transformation and integration with the European Union, changes aimed at enhancement of economic innovation, competitiveness and effectiveness. An active labour market policy plays an important role in a situation characterized by high structural unemployment. Efficiently applied instruments of an active labour market policy can reduce this unemployment. Therefore, the main aim of this paper is to evaluate the role of the active labour market policy in Poland between 2005-2010, taking into consideration the characteristics of its main instruments, its participants, and expenditures.
Measuring the Performance of Local Government Entities and Analysis of their Managers’ and Personnel’s Information Needs in the Context of "New Public Management"
Authors: Zarzycka Ewelina , Michalak Marcin
Published: September 2013

Ways to make the public sector more effective and efficient have been vigorously discussed for more than thirty years by practitioners and researchers all over the world. Public sector reforms drawing on the paradigm of an entrepreneurial and market style of management are called New Public Management (NPM). However if the concept of managing public sector entities according to the best management practices in the private sector is to be implemented and used effectively, the necessary management-aid tools must be introduced. This particularly applies to the public sector’s accounting system oriented to external reporting, to which needs to be added a management accounting subsystem with cost accounting and budgeting based on responsibility accounting and a measurement, evaluation, and performance reporting subsystem. The main research objectives of this article are the following:  - to identify the management accounting methods and tools currently used by the managers of sampled local government entities (LGEs);  - to identify the information needs of the LGEs’ managers and personnel related to the implementation and application of a management accounting system, and to find out what accounting methods and tools they would like to have at their disposal to improve management processes;  - to evaluate the usefulness, adequacy and effectiveness of performance measurement systems used in LGEs. This article fits into the scope of world research on the implementations of the NPM concept and uses New Institutional Economy to better understand the implementation of management accounting in the public sector.
Vitamin D Immunomodulatory Potential in Multiple Sclerosis
Authors: Slavov Georgi S. , Trenova Anastasiya G. , Manova Mariya G. , Kostadinova Ivanka I. , Vasileva Tonka V. , Zahariev Zahari I.
Published: September 2013

Multiple sclerosis (MS) is an autoimmune disease of unknown etiology whose treatment is of limited efficiency and therefore has a high social burden. As it has been suggested that myelin destruction model, the clinical manifestation and the potential of therapeutic response in MS are correlated, it is quite justifiable that we study various factors (genetic, hormonal, environmental) that take part in the autoimmune process in order to improve the control over the disrupted immune regulation. Results from epidemiological and clinical studies clearly suggest that changes in vitamin D serum concentrations are correlated with the magnitude of the risk of developing MS, the phases of relapse and remittance and with gender differences in vitamin D metabolism. Experimental and clinical studies also have established that 25-hydroxy vitamin D (25(OH)D) and 1,25-dihydroxy vitamin D (1,25(OH)2D) exert an immunomodulatory effect in the central nervous system and peripheral organs of the immune system. The standard reference range of vitamin D concentration in serum is 50-80 nmol/l - it provides normal calcium metabolism. Issues that are discussed include the vitamin D serum concentration needed to suppress the aberrant immune response in MS patients; a subgroup of MS patients suitable for vitamin D treatment, the vitamin D being applied in optimally effective and safe dosage. MS prevalence rate in Bulgaria has increased two-fold in 17 years but this is a rather short interval to be able to assume that the gene pool of the population changes. Thus further studies on possible interactions between different environmental factors and these factors’ role in the disease pathogenesis are justified and necessary.
Serum Melatonin in Women with Polycystic Ovary Syndrome
Authors: Terzieva Dora D. , Orbetzova Maria M. , Mitkov Mitko D. , Mateva Nonka G.
Published: September 2013

There has been a surge of interest in recent years in studying the changes of serum melatonin concentrations in disorders that are associated with insulin resistance such as diabetes mellitus type 2 and polycystic ovary syndrome (PCOS).

AIM: The present study was designed to investigate the day-time and night-time levels of serum melatonin and the cortisol rhythm in women with PCOS and compare them with those of healthy women.

PATIENTS AND METHODS: This is a case-control study which included 30 women with PCOS and 25 healthy women. All hormonal measurements in both the study group and controls were carried out between days 3 and 5 counted from the beginning of the last regular menstrual cycle; they included serum levels of melatonin and cortisol at 03:00 a.m and 08:00 a.m, total testosterone (T), dehydroepiandrosterone sulfate (DHEA-S), luteinizing hormone (LH), follicle stimulating hormone (FSH), and immunoreactive insulin at 08:00 a.m. RESULTS: Women with PCOS were found to have a significantly higher melatonin level at 08:00 a.m. and smaller mean night-day difference in the concentrations of melatonin in comparison with those of healthy women (natural log (Ln) night-day difference 0.60 ± 0.10 pg/ml versus 1.15 ± 0.14, p < 0.002). Melatonin to cortisol ratios at 03:00 a.m. and 08:00 a.m. showed no statistically significant differences between the two groups (Ln melatonin/ cortisol 03:00 a.m., 1.01 ± 0.06 versus 1.05 ± 0.05; Ln melatonin/cortisol at 08:00 a.m., 0.62 ± 0.01 versus 0.56 ± 0.03, p > 0.05).

CONCLUSION: The results we obtained about the changes of melatonin in women with PCOS could help in elucidating the complex pathophysiological pattern of this disease.
Professional Burnout Syndrome Among Correctional Facility Officers
Authors: Harizanova Stanislava N. , Tarnovska Tanya H.
Published: September 2013

INTRODUCTION: Correctional facilities present unique work places - the employees there work in tough, demanding and hazardous working conditions, in real life-threatening environment, subjected to physical and mental fatigue, risk of infectious diseases, work in shifts, with inadequate pay, etc. The aim of this study was to find the prevalence and level of burnout syndrome among employees working in the District Prison of the town of Plovdiv.

MATERIAL AND METHODS: The study included all employees that had direct contact with the inmates in the prison. We recruited 106 employees that participated in the study anonymously and voluntarily. The main instrument we used was the questionnaire designed according to the methods developed by V. Boiko, which allows identification of professional burnout syndrome in its three phases with four symptoms in each of the phases.

RESULTS: We found a high prevalence of burnout syndrome among the staff in the District Prison in Plovdiv (74.53%). All three phases of burnout were found to have a high prevalence rate - the stress phase: 48.11%, the resistance phase: 66.98%, the exhaustion phase: 41.51%. The rank in the service hierarchy was found to be a predictor in the stress phase, B = 0.701, p = 0.048, Exp(B) = 2.106, 95%CI [1.00; 4.04]. The single officers (83.33% of the divorced and 55.56% of the single employees) and those of the staff that were more highly educated (78.72%) had elevated levels of burnout syndrome, and these manifested during the first 5 years of their service in the prison (77.78%).

CONCLUSION: In Bulgaria at present the burnout syndrome has not been studied among employees working in correctional facilities. We found a high prevalence of the syndrome among the employees of the District Prison - Plovdiv. The younger, the single and the more educated employees had greater levels of burnout syndrome, which manifest during the first 5 years of their service. The results suggest that there is a need to develop and implement effective strategies to reduce and prevent development of burnout syndrome.
Notes on Orthoptera (Insecta) and their Assemblages in the Romanian Carpathians
Authors: Krištín Anton , Jarčuška Benjamín , Kaňuch Peter , Iorgu Elena Iulia , Iorgu Ionuţ Ştefan
Published: September 2013

The Carpathian Mountains, particularly the Eastern Carpathians, represent an area with a high diversity and endemism in grasshoppers and bush-crickets. The well-preserved mountain grassland habitats are populated by diverse orthopteran assemblages. During the second half of July 2013, we visited 24 sites in Romanian Carpathians within altitudes ranging from 237 to 1700 m a.s.l. and found 71 Orthoptera species (36 Ensifera and 35 Caelifera). These represent 37.3% of the 190 species known to occur in Romania. Nine Carpathian endemics (Isophya stysi, Pholidoptera frivaldskyi, Pholidoptera transsylvanica, Miramella ebneri, Pseudopodisma transilvanica, Isophya harzi, Isophya nagyi, Isophya sicula, Zubovskya banatica), of which the last four are endemic to Romania and Eastern Carpathians, were recorded. Four environmental characteristics, i.e. habitat type, altitude, mean temperature and precipitation on sampled sites, are used to examine the structure of orthopteran assemblages by using DCA. Also, more detailed information on the occurrence of rare and endemic species is given.
New Data on the Knowledge of Beetle Fauna (Insecta: Coleoptera) in the “Bârnova-Repedea Forest” Site of Community Importance (Rosci 01235, Iaşi, Romania
Authors: Stan Melania , Nitzu Eugen
Published: September 2013

103 coleopteran species, belonging to 11 families were found during our faunal sampling in 2012 in the Bârnova-Repedea Forest site. Out of them Carabus variolosus Fabricius, Lucanus cervus (Linnaeus), Cerambyx cerdo Linnaeus, Morimus funereus Mulsant and Rosalia alpina (Linnaeus) are species of community interest, included in the Annex II of the Habitat Directive. Carpelimus gusarovi Gildenkov and Stenus doderoi Bondroit were collected by the authors, for the first time in Romania. Carabus excellens (Fabricius), a rare species, was rediscovered in this site, and specific faunistic data on the species Colon (Myloechus) dentipes (C. R. Sahlberg) are provided for the first time.
Salinity Tolerance in Pelobates Fuscus (Laurenti, 1768) Tadpoles (Amphibia: Pelobatidae)
Authors: Stănescu Florina , Iosif Ruben , Székely Diana , Székely Paul , Roşioru Daniela , Cogălniceanu Dan
Published: September 2013

We investigated the effect of salinity on larval development and survival rate to metamorphosis in the common spadefoot toad Pelobates fuscus (Laurenti, 1768). Our hypothesis was that higher salinity would decrease tadpole survival rate and body size at metamorphosis, and delay metamorphosis. The response of the tadpoles was evaluated through an experimental design with three salinity treatments of 2, 4, and 8‰ compared to a control (deionized water). Survival varied across the treatments: neither of the tadpoles in 8‰ salinity treatment survived the experiment, nor achieved metamorphosis. Salinity levels of 2 and 4‰ had no significant influence on the mean time to metamorphosis, body mass and SVL at metamorphosis. Our results suggest that P. fuscus tadpoles have a tolerance threshold for brackish water up to 4‰, above which survival is impaired.
Spatial and Temporal Distribution of the Zooplankton Biomass in Sfântu Gheorghe Branch (The Danube Delta, Romania) in Relation to Environmental Factors
Authors: Florescu Larisa , Parpală Laura , Dumitrache Alina , Moldoveanu Mirela
Published: September 2013

Sfântu Gheorghe fluvial branch belongs to the macroregional hydrological system of the Danube Delta. In order to improve the navigation on the river branches, between 1983 and 1989 various technical works have been initiated, which later proved to be one of the most aggressive factors leading to changes over time in the Danube Delta. The influence of anthropogenic impact on the zooplankton biomass distribution patterns in Sfântu Gheorghe was investigated in 2008 - 2010 interval. From this perspective, the aim of this paper was to emphasize the structure and distribution of zooplankton in the new conditions of the river system. Seasonal sampling shows that Copepoda and Cladocera were the dominant groups while the protozoans (Ciliata and Testacea) presented the smallest values of biomass and also emphasized distinct differences among the three sampling periods: summer, spring and autumn.
Is Separate Always Unequal? A Philosophical Examination of Ideas of Equality in Key Cases Regarding Racial and Linguistic Minorities in Education
Authors: Thompson Karen D.
Published: September 2013

Advocates for language minority students depict the movement for language minority students’ rights as an outgrowth of the civil rights movement, which focused initially on securing rights for racial minorities. This article examines whether the same conceptions of equality and legal remedies apply for both groups. Building on Berlin’s notions of negative and positive liberty, I identify two conceptions of equality evoked in key legal cases regarding racial and linguistic minorities: negative equality, which consists of removing morally untenable discriminatory practices to ensure equality via similar treatment, and positive equality, which consists of ensuring equality by customizing treatment depending on a group’s particular needs. While these two conceptions of equality may appear at odds, I propose that the least restrictive environment standard, emanating from disability law, can serve to reconcile the two, holding that negative equality is paramount but positive equality may sometimes be necessary in time-bound, limited contexts.
New Evidence on Teacher Labor Supply
Authors: Engel Mimi , Jacob Brian A. , Curran F. Chris
Published: September 2013

Recent evidence on the large variance in teacher effectiveness has spurred interest in teacher labor markets. Research documents that better qualified teachers typically work in more advantaged schools but cannot determine the relative importance of supply versus demand. To isolate teacher preferences, we document which schools prospective teachers interviewed at during job fairs in Chicago. We find substantial variation in the number of applicants per school, ranging from under five to over 300. Schools serving more advantaged students have more applicants per vacancy, on average, and teacher preferences vary systematically by their own demographic characteristics. School geographic location is highly predictive of applications, even after controlling for distance from applicants’ home addresses and a host of school and neighborhood characteristics.