bluuebunny/crossref_metadata_2025 huggingface dataset:
Fatores predisponentes de desordem temporomandibular em crianças com 6 a 11 anos de idade ao início do tratamento ortodôntico
Authors: Loddi Patrícia Porto , Miranda André Luis Ribeiro de , Vieira Marilena Manno , Chiari Brasília Maria , Goldenberg Fernanda Cavicchioli , Mandetta Savério
Published: June 2010

INTRODUÇÃO: atualmente, considera-se multifatorial a etiologia da desordem temporomandibular (DTM), na qual fatores psicológicos, parafunções orais, má oclusão morfológica e funcional constituem possíveis causas para o desenvolvimento dessa disfunção. OBJETIVO: avaliar as crianças que procuram por tratamento ortodôntico preventivo, visando compreender melhor suas queixas e avaliar a prevalência de sinais e sintomas de desordem temporomandibular. MÉTODOS: sessenta e cinco crianças, com idades variando entre 6 e 11 anos, foram avaliadas por dois examinadores. RESULTADOS: o bruxismo foi o sintoma que apresentou o maior índice de prevalência na amostra estudada e a deglutição atípica apresentou o maior índice dentre os fatores predisponentes. CONCLUSÃO: recomenda-se que a avaliação dos possíveis sinais e sintomas da DTM em crianças seja adotada como rotina durante o exame clínico inicial.
Extrações dentárias em Ortodontia: avaliação de elementos de diagnóstico
Authors: Ruellas Antônio Carlos de Oliveira , Ruellas Ricardo Martins de Oliveira , Romano Fábio Lourenço , Pithon Matheus Melo , Santos Rogério Lacerda dos
Published: June 2010

Algumas más oclusões exigem do ortodontista capacidade de diagnóstico para decidir pela melhor maneira de tratar o paciente. O objetivo dos autores deste artigo foi apresentar casos clínicos e discutir alguns elementos de diagnóstico utilizados na elaboração do plano de tratamento, auxiliando na decisão de extrair dentes. Foi dada ênfase em cada elemento de diagnóstico: aspectos relacionados à cooperação, discrepância de modelo, discrepância cefalométrica e perfil facial, idade esquelética (crescimento) e relações anteroposteriores, assimetrias dentárias, padrão facial e patologias. Sugere-se que a associação dos aspectos citados é importante para a decisão correta. Todavia, algumas vezes, uma característica, por si só, pode definir o plano de tratamento.
Metacognitive strategy teaching in the ESL oral classroom
Authors: Lam Wendy Y.K.
Published: June 2010

While strategy instruction research generally focuses on the effect of the teaching on learners’ use of the strategies targeted for instruction, the present study examines the ‘wash over’ effect on learners’ use of pre-existing, non-target strategies. The study involved a treatment class and a comparison class in the ESL oral classroom in Hong Kong. A quasi-experimental design was adopted in which the treatment class received metacognitive strategy instruction to enhance students’ ability to manage English group discussion tasks. A data collection method comprising observations and stimulated recall interviews that aimed to tap respectively overt strategy use and covert strategic thoughts was employed. The findings indicate that, for the treatment class, while there seemed to be no ‘wash over’ effect from target to non-target strategies in the frequency of use of the whole sample of non-target strategies over time, there were increases in the frequency of use of individual, non-target strategies that were pertinent to the specific nature of small group discussion tasks. The findings are discussed with respect to the differential and desirable effects of the strategy teaching and to the relationship between task type and strategy choice. Implications for strategy instruction will also be drawn.
Opportunity Costs and the Probability of War in an Incomplete Information Game (With Comments by Lloyd Jeff Dumas)
Authors: Polachek Solomon W , Xiang Jun
Published: June 2010

This paper summarizes conclusions reached in Polachek and Xiang (International Organization, 2010). It shows how gains from trade decrease the probability of war in an incomplete information game. The result reaffirms how opportunity costs explain the inverse trade-conflict relationship found in current empirical literature on the subject. The ensuing discussion puts the result in the broader context of peacekeeping.
The Roles that Forecast Surprise and Forecast Error Play in Determining Management Forecast Precision
Authors: Choi Jong-Hag , Myers Linda A. , Zang Yoonseok , Ziebart David A.
Published: June 2010

SYNOPSIS: Studying the determinants of management forecast precision is important because a better understanding of the factors affecting management’s choice of forecast precision can provide investors and other users with cues about the characteristics of the information contained in the forecasts. In addition, as regulators assess the regulation of voluntary management disclosures, they need to better understand how managers choose among forecast precision disclosure alternatives. Using 16,872 management earnings forecasts collected from 1995 through 2004, we provide strong evidence that forecast precision is negatively associated with the magnitude of the forecast surprise and that this negative association is stronger when the forecast is bad news than when it is good news. We also find that forecast precision is negatively associated with the absolute magnitude of the forecast error that proxies for the forecast uncertainty that managers face when they issue forecasts, and that the negative association is stronger when forecast errors are negative. These results are consistent with greater liability concerns related to bad news forecasts and negative forecast errors, respectively. Our study provides educators and researchers with important insights into management’s choice of earnings forecast precision, which is a component of the voluntary disclosure process that is not well understood.
Neuroaccounting: Consilience between the Biologically Evolved Brain and Culturally Evolved Accounting Principles
Authors: Dickhaut John , Basu Sudipta , McCabe Kevin , Waymire Greg
Published: June 2010

SYNOPSIS: We develop the hypothesis that culturally evolved accounting principles will be ultimately explained by their consilience with how the human brain has evolved biologically to evaluate social and economic exchange. We provide background on the structure and evolution of the brain, the measurement of brain behavior during economic decision making, and the brain’s central role in building economic institutions. We describe the emergence of modern accounting principles and argue that the primary function of accounting in evaluating exchange is to provide quantified information on the net benefits of past exchanges. We review evidence documented by neuroscientists that is consistent with the hypothesis that longstanding accounting principles (e.g., Revenue Realization and Conservatism) have distinct parallels in brain behaviors. Our analysis of Neuroaccounting extends Basu and Waymire (2006) to provide a new way to scientifically view accounting, which has implications for how we think about the origins and persistence of longstanding accounting principles.
The American Accounting Association’s Financial Reporting Policy Committee’s Response to the Preliminary Views on Financial Statement Presentation
Authors:   The Financial Reporting Policy Committee of the Financial Accounting and Reporting Section of the American Accounting Association, Bradshaw Mark , Callahan Carolyn , Ciesielski Jack , Gordon Elizabeth , Kohlbeck Mark , Hodder Leslie , Hopkins Patrick E. , Laux Robert , McVay Sarah , Stober Thomas , Stocken Phillip , Yohn Teri Lombardi
Published: June 2010

SYNOPSIS: The Financial Accounting Standards Board and the International Accounting Standards Board (hereafter, the Boards) issued the discussion paper Preliminary Views on Financial Statement Presentation in late 2008. The Boards propose to significantly reconfigure the presentation of financial statements to offer parallel statements with standardized partitions of each financial statement into five categories: business activities, financing activities, income taxes, discontinued operations, and equity. The allocation of transactions within these partitions will depend crucially on management’s assessment of each transaction (i.e., the management approach). In this paper we comment on the proposal, with particular emphasis on empirical evidence and relevant theories from academic research. We highlight benefits of the proposed changes as well as some possible concerns. We conclude that the objective of providing a cohesive picture of activities through a uniform standardization of each financial statement by activity is desirable, but the proposed criteria for how activities are categorized results in potentially aberrant or confusing outcomes. Thus, any dissatisfaction with the current financial statement format may be replaced with other criticisms. Finally, the current proposal relies on the effectiveness of the management approach, which can only be successful if managers embrace the proposed structure.
Perinatal Changes in Mitral and Aortic Valve Structure and Composition
Authors: Stephens Elizabeth H. , Post Allison D. , Laucirica Daniel R. , Grande-Allen K. Jane
Published: June 2010

At birth, the mechanical environment of valves changes radically as fetal shunts close and pulmonary and systemic vascular resistances change. Given that valves are reported to be mechanosensitive, we investigated remodeling induced by perinatal changes by examining compositional and structural differences of aortic and mitral valves (AVs, MVs) between 2-day-old and 3rd fetal trimester porcine valves using immunohistochemistry and Movat pentachrome staining. Aortic valve composition changed more with birth than the MV, consistent with a greater change in AV hemodynamics. At 2 days, AV demonstrated a trend of greater versican and elastin ( P = 0.055), as well as greater hyaluronan turnover (hyaluronan receptor for endocytosis, P = 0.049) compared with the 3rd-trimester samples. The AVs also demonstrated decreases in proteins related to collagen synthesis and fibrillogenesis with birth, including procollagen I, prolyl 4-hydroxylase, biglycan (all P ≤ 0.005), and decorin ( P = 0.059, trend). Both AVs and MVs demonstrated greater delineation between the leaflet layers in 2-day-old compared with 3rd-trimester samples, and AVs demonstrated greater saffron-staining collagen intensity, suggesting more mature collagen in 2-day-old compared with 3rd-trimester samples (each P < 0.05). The proportion of saffron-staining collagen also increased in AV with birth ( P < 0.05). The compositional and structural changes that occur with birth, as noted in this study, likely are important to proper neonatal valve function. Furthermore, normal perinatal changes in hemodynamics often do not occur in congenital valve disease; the corresponding perinatal matrix maturation may also be lacking and could contribute to poor function of congenitally malformed valves.
A Methodology for Improving Strategic Decisions in Social Systems with a Lack of Information
Authors: Verna Carlos , Škraba Andrej
Published: June 2010

A Methodology for Improving Strategic Decisions in Social Systems with a Lack of Information

The design of strategies for social systems requires the use of qualitative information owing to the fact that quantitative information can be insufficient to solve the problems involved. The information that the specialists and the decision makers obtain is often incomplete and unreliable. Nevertheless, leaders have to make strategic decisions despite these deficiencies which should be based on the formal models (Kljajić et al. 2000; Škraba et al, 2003; Škraba et al 2007).

This paper describes a methodology elaborated to design the strategy of the city of Santa Cruz (on the Canary Islands). It has two main sections: the elaboration of a qualitative model and the use of System Dynamics. We combine them in a way that allows mixing qualitative and quantitative information to achieve a better understanding of the structure of the region, to know the tendencies of the present scenario and to estimate of the effects of alternative strategic decisions. We have obtained these results working with scarce quantitative information. This methodology may be applied to any social systems with similar characteristics.
The COMPRAM Methodology and Complex Societal Problems-an Analysis of the Case of Children Born of War
Authors: Mochmann Ingvill , DeTombe Dorien
Published: June 2010

The COMPRAM Methodology and Complex Societal Problems-an Analysis of the Case of Children Born of War

During and after wars children are born where the father is a member of an occupation or peacekeeping force and the mother a local citizen. Securing the human rights of children born of war is often highly complex and involves researchers and practitioners from different disciplines. The Compram methodology on handling complex societal problems will be applied to analyse whether the methodology is suitable on this group of war-affected children. The Compram methodology is a multi disciplined, multi level, multi actor methodology based on the theory of societal complexity. The methodology gives guidelines to handle real life complex societal problems.
Development of a Web Application for Dynamic Production Scheduling in Small and Medium Enterprises
Authors: Kofjač Davorin , Knaflič Andrej , Kljajić Miroljub
Published: June 2010

Development of a Web Application for Dynamic Production Scheduling in Small and Medium Enterprises

This article describes the development of a web-based dynamic job-shop scheduling system for small and medium enterprises. In large enterprises, scheduling is mainly performed with appropriate technology by human experts; many small and medium enterprises lack the resources to implement such a task. The main objective was to develop a cost-effective, efficient solution for job-shop scheduling in small and medium enterprises with an emphasis on accessibility, platform independence and ease of use. For these reasons, we decided to develop a web-based solution with the main emphasis on the development of an intelligent and dynamic user interface. The solution is built upon modular programming principles and enables dynamic scheduling on the basis of artificial intelligence, i.e. genetic algorithms. The solution has been developed as a standalone information system, which allows the management of virtually all scheduling activities through an administration panel. In addition, the solution covers the five main functionalities that completely support the scheduling process, i.e. making an inventory of resources available in the company, using it in the process of production planning, collecting data on production activities, distribution of up-to-date information and insight over events in the system.
Simulated Decision Learning in a Multiactor Setting
Authors: Asproth Viveca , Holmberg Stig , Löfstedt Ulrica
Published: June 2010

Simulated Decision Learning in a Multiactor Setting

The idea of decision analysis-and subsequent learning from the outcomes-is old within Operational Research. Here this approach to continuous improvement of decision outcomes is put one step further within the area of crisis and disaster management. This is done by introducing multiactors making simultaneous decisions with just partial information about each other. Further, decision outcomes are achieved from a simulation model rather than from the real object system.
Error calibration of quasi-geoidal, normal and ellipsoidal heights of Sweden using variance component estimation
Authors: Eshagh Mehdi
Published: June 2010

Error calibration of quasi-geoidal, normal and ellipsoidal heights of Sweden using variance component estimation

Errors of estimated parameters in an adjustment process should be scaled according to the size of the estimated residuals or misclosures. After computing a quasi-geoid (geoid), its biases and tilts, due to existence of systematic errors in the terrestrial data, are removed by fitting a corrective surface to the misclosures of the differences between the GNSS/levelling data and the quasi-geoid (geoid). Variance component estimation can be used to re-scale or calibrate the error of the GNSS/levelling data and the quasi-geoid (geoid) model. This paper uses this method to calibrate the errors of the recent quasi-geoid model, the GNSS and the normal heights of Sweden. Different stochastic models are investigated in this study and based on a 7-parameter corrective surface model and a three-variance component stochastic model, the calibrated error of the quasi-geoid and the normal heights are 6 mm and 5 mm, respectively and the re-scaled error of the GNSS heights is 18 mm.
A mathematical model of the bathymetry-generated external gravitational field
Authors: Tenzer Robert , Vajda Peter , Hamayun Peter
Published: June 2010

A mathematical model of the bathymetry-generated external gravitational field

The currently available global geopotential models and the global elevation and bathymetry data allow modelling the topography-corrected and bathymetry stripped reference gravity field to a very high spectral resolution (up to degree 2160 of spherical harmonics) using methods for a spherical harmonic analysis and synthesis of the gravity field. When modelling the topography-corrected and crust-density-contrast stripped reference gravity field, additional stripping corrections are applied due to the ice, sediment and other major known density contrasts within the Earth's crust. The currently available data of global crustal density structures have, however, a very low resolution and accuracy. The compilation of the global crust density contrast stripped gravity field is thus limited to a low spectral resolution, typically up to degree 180 of spherical harmonics. In this study we derive the expressions used in forward modelling of the bathymetry-generated gravitational field quantities and the corresponding bathymetric stripping corrections to gravity field quantities by means of the spherical bathymetric (ocean bottom depth) functions. The expressions for the potential and its radial derivative are formulated for the adopted constant (average) ocean saltwater density contrast and for the spherical approximation of the geoid surface. These newly derived expressions are utilized in numerical examples to compute the gravitational potential and attraction generated by the ocean density contrast. The computation is realized globally on a 1 x 1 arc-deg geographical grid at the Earth's surface.
Generalized geoidal estimators for deterministic modifications of spherical Stokes' function
Authors: Šprlák Michal
Published: June 2010

Generalized geoidal estimators for deterministic modifications of spherical Stokes' function

Stokes' integral, representing a surface integral from the product of terrestrial gravity data and spherical Stokes' function, is the theoretical basis for the modelling of the local geoid. For the practical determination of the local geoid, due to restricted knowledge and availability of terrestrial gravity data, this has to be combined with the global gravity model. In addition, the maximum degree and order of spherical harmonic coefficients in the global gravity model is finite. Therefore, modifications of spherical Stokes' function are used to obtain faster convergence of the spherical harmonic expansion. Decomposition of Stokes' integral and modifications of Stokes' function have been studied by many geodesists. In this paper, the proposed deterministic modifications of spherical Stokes' function are generalized. Moreover, generalized geoidal estimators, when the Stokes' integral is decomposed in to spectral and frequency domains, are introduced. Higher derivatives of spherical Stokes' function and their numerical stability are discussed. Filtering and convergence properties for deterministic modifications of the spherical Stokes' function in the form of a remainder of the Taylor polynomial are studied as well.
Instructional Coaching
Authors: Gallucci Chrysan , Van Lare Michelle DeVoogt , Yoon Irene H. , Boatright Beth
Published: June 2010

Instructional coach initiatives aimed at teachers’ professional development are expanding in reforming school districts across the United States. This study addresses the lack of research regarding the professional development of instructional coaches. Drawing on sociocultural learning theory, specifically a model called the Vygotsky Space, the authors use a case approach to examine the learning experiences of a single secondary literacy coach. Hypotheses suggest that (a) coaches are not unproblematic conduits of reform ideas but are also learners of new content and pedagogy; (b) as coaches’ conceptual development about instruction grows, their ability to coach also matures; and (c) professional development that supports coaches is best aligned around a workplace pedagogy that addresses the learning needs of multiple system actors.
Multiple intradural-extramedullary ependymomas: proven dissemination by genetic analysis
Authors: Vural Murat , Arslantas Ali , Ciftci Evrim , Artan Sevilhan , Adapinar Baki
Published: June 2010

This 45-year-old woman was admitted with neck and back pain and difficulty in ambulation that had been progressively worsening for 2 years. Admission MR imaging revealed a cervicomedullary junction tumor and 2 intradural-extramedullary spinal tumors located separately at the levels of T5–6 and T8–9. All masses were successfully resected in a 2-stage operation. Histopathological examination of the surgical specimens revealed that all the lesions were ependymomas. Genetic analysis was performed to determine if the tumors were related. Conventional cytogenetics, multiplex fluorescence in situ hybridization (M-FISH), interphase-FISH specific to 22q11, and epidermal growth factor receptor loci analyses of the tumor samples revealed that the lesions originated from the same primary tumor. Although 3 simultaneous tumors in different compartments of the neural axis were diagnosed as ependymoma by histopathological examination, it was not possible to be sure if their multiplicity was due to spread of tumor cells via CSF or if it was due to multicentric foci. Thus, genetic analysis of the tumor samples is essential to confirm the exact mechanism of development of multiple ependymomas.
Posterior occipitocervical (C0–3) fusion using polyaxial occipital condyle to cervical spine screw and rod fixation: a radiographic and cadaveric analysis
Authors: Frankel Bruce M. , Hanley Michael , Vandergrift Alex , Monroe Timothy , Morgan Steven , Rumboldt Zoran
Published: June 2010

Numerous conditions affect the occipitocervical junction requiring treatment with occipitocervical fixation. In this paper the authors present their technique of craniocervical fixation achieved with the cephalad extension of posterior C1–3 polyaxial screw and rods to polyaxial screws placed in the occipital condyles. They retrospectively analyzed occipital condyle morphology obtained from CT analyses of 40 patients with normal cervical spines, evaluated occipital condyle screw placement feasibility in 4 cadavers, and provided a case report of a 70-year-old woman with rheumatoid arthritis, basilar invagination, and atlantoaxial instability who was treated with this novel technique. Based on radiographic analysis of occipital condyle anatomy, they concluded that on average a 3.5-mm-diameter × 20- to 30-mm-long screw can be safely placed at an angle of 20–33° from the sagittal plane. Overall, measuring the condylar heights (mean [± SD] 10.8 ± 1.5 mm, range 8.1–15.0 mm), widths (mean 11.1 ± 1.4 mm, range 8.5–14.2 mm), lengths (20.3 ± 2.1 mm, range 15.4–24.6 mm), and angles (mean 32.8 ± 5.2°, range 20.2–45.8°) by using CT studies is an accurate and precise method. This finding correlates with the results of prior anatomical studies of occipital condyles and is important in the planning of craniovertebral junction surgery.
Improving accuracy and reducing radiation exposure in minimally invasive lumbar interbody fusion
Authors: Wood Martin James , Mannion Richard John
Published: June 2010

Object

The authors assessed the accuracy of placement of lumbar transpedicular screws by using a computer-assisted, imaged-guided, minimally invasive technique with continuous electromyography (EMG) monitoring.

Methods

This was a consecutive case series with prospective assessment of procedural accuracy. Forty-seven consecutive patients underwent minimally invasive lumbar interbody fusion and placement of pedicle screws (PSs). A computer-assisted image guidance system involving CT-based images was used to guide screw placement, while EMG continuously monitored the lumbar nerve roots at the operated levels with a 5-mA stimulus applied through the pedicle access needle. All patients underwent CT scanning to determine accuracy of PS placement. All episodes of adjusted screw trajectory based on positive EMG responses were recorded. Pedicle screw misplacement was defined as breach of the pedicle cortex by the screw of more than 2 mm.

Results

Two hundred twelve PSs were inserted in 47 patients. The screw misplacement rate was 4.7%. One patient experienced new postoperative radiculopathy resulting from a sacral screw that was too long, with lumbosacral trunk impingement. The trajectory of the pedicle access needle was altered intraoperatively on 20 occasions (9.4% of the PSs) based on positive EMG responses, suggesting that nerve root impingement may have resulted from these screws had the EMG monitoring not been used.

Conclusions

The combination of computer-assisted navigation combined with continuous EMG monitoring during pedicle cannulation results in a low rate of PS misplacement, with avoidance of screw positions that might cause neural injury. Furthermore, this technique allows reduction of the radiation exposure for the surgical team without compromising the accuracy of screw placement.
Risk factors for surgical site infection following spine surgery: efficacy of intraoperative saline irrigation
Authors: Watanabe Masahiko , Sakai Daisuke , Matsuyama Daisuke , Yamamoto Yukihiro , Sato Masato , Mochida Joji
Published: June 2010

Object

The purpose of this study was to identify risk factors for surgical site infection after spine surgery, noting the amount of saline used for intraoperative irrigation to minimize wound contamination.

Methods

The authors studied 223 consecutive spine operations from January 2006 through December 2006 at our institute. For a case to meet inclusion criteria as a site infection, it needed to require surgical incision and drainage and show positive intraoperative cultures. Preoperative and intraoperative data regarding each patient were collected. Patient characteristics recorded included age, sex, and body mass index (BMI). Preoperative risk factors included preoperative hospital stay, history of smoking, presence of diabetes, and an operation for a traumatized spine. Intraoperative factors that might have been risk factors for infection were collected and analyzed; these included type of procedure, estimated blood loss, duration of operation, and mean amount of saline used for irrigation per hour. Data were subjected to univariate and multivariate logistic regression analyses.

Results

The incidence of surgical site infection in this population was 6.3%. According to the univariate analysis, there was a significant difference in the mean duration of operation and intraoperative blood loss, but not in patient age, BMI, or preoperative hospital stay. The mean amount of saline used for irrigation in the infected group was less than in the noninfected group, but was not significantly different. In the multivariate analysis, sex, advanced age (> 60 years), smoking history, and obesity (BMI > 25 kg/m2) did not show significant differences. In the analysis of patient characteristics, only diabetes (patients receiving any medications or insulin therapy at the time of surgery) was independently associated with an increased risk of surgical site infection (OR 4.88). In the comparison of trauma and elective surgery, trauma showed a significant association with surgical site infection (OR 9.42). In the analysis of surgical factors, a sufficient amount of saline for irrigation (mean > 2000 ml/hour) showed a strong association with the prevention of surgical site infection (OR 0.08), but prolonged operation time (> 3 hours), high blood loss (> 300 g), and instrumentation were not associated with surgical site infection.

Conclusions

Diabetes, trauma, and insufficient intraoperative irrigation of the surgical wound were independent and direct risk factors for surgical site infection following spine surgery. To prevent surgical site infection in spine surgery, it is important to control the perioperative serum glucose levels in patients with diabetes, avoid any delay of surgery in patients with trauma, and decrease intraoperative contamination by irrigating > 2000 ml/hour of saline in all patients.
Quantitative analysis of misplaced pedicle screws in the thoracic spine: how much pullout strength is lost?
Authors: Brasiliense Leonardo B. C. , Theodore Nicholas , Lazaro Bruno C. R. , Sayed Zafar A. , Deniz Fatih Ersay , Sonntag Volker K. H. , Crawford Neil R.
Published: June 2010

Object

The object of this study was to investigate the effects of iatrogenic pedicle perforations from screw misplacement on the mean pullout strength of thoracic pedicle screws.

Methods

Forty human thoracic vertebrae (T6–11) from human cadavers were studied. Before pedicle screws were inserted, the specimens were separated into 4 groups according to the type of screw used: 1) standard pedicle screw (no cortical perforation); 2) screw with medial cortical perforation; 3) screw with lateral cortical perforation; and 4) “airball” screw (a screw that completely missed the vertebral body). Consistency among the groups for bone mineral density, pedicle diameter, and screw insertion depth was evaluated. Finally, each screw was pulled out at a constant displacement rate of 10 mm/minute while ultimate strength was recorded.

Results

Compared with well-placed pedicle screws, medially misplaced screws had 8% greater mean pullout strength (p = 0.482) and laterally misplaced screws had 21% less mean pullout strength (p = 0.059). The difference in mean pullout strength between screws with medial and lateral cortical perforations was significant (p = 0.013). Airball screws had only 66% of the mean pullout strength of well-placed screws (p = 0.009) and had 16% lower mean pullout strength than laterally misplaced screws (p = 0.395).

Conclusions

This in vitro study showed a significant difference in mean pullout strength between medial and lateral misplaced pedicle screws. Moreover, airball screws were associated with a significant loss of pullout strength.
Morbidity and mortality in the surgical treatment of 10,329 adults with degenerative lumbar stenosis
Authors: Fu Kai-Ming G. , Smith Justin S. , Polly David W. , Perra Joseph H. , Sansur Charles A. , Berven Sigurd H. , Broadstone Paul A. , Choma Theodore J. , Goytan Michael J. , Noordeen Hilali H. , Knapp D. Raymond , Hart Robert A. , Zeller Reinhard D. , Donaldson William F. , Boachie-Adjei Oheneba , Shaffrey Christopher I.
Published: June 2010

Object

The purpose of this study was to evaluate the prospectively collected Scoliosis Research Society (SRS) database to assess the incidences of morbidity and mortality (M&M) in the operative treatment of degenerative lumbar stenosis, one of the most common procedures performed by spine surgeons.

Methods

All patients who underwent surgical treatment for degenerative lumbar stenosis between 2004 and 2007 were identified from the SRS M&M database. Inclusion criteria for analysis included an age ≥ 21 years and no history of lumbar surgery. Patients were treated with either decompression alone or decompression with concomitant fusion. Statistical comparisons were performed using a 2-sided Fisher exact test.

Results

Of the 10,329 patients who met the inclusion criteria, 6609 (64%) were treated with decompression alone, and 3720 (36%) were treated with decompression and fusion. Among those who underwent fusion, instrumentation was placed in 3377 (91%). The overall mean patient age was 63 ± 13 years (range 21–96 years). Seven hundred nineteen complications (7.0%), including 13 deaths (0.1%), were identified. New neurological deficits were reported in 0.6% of patients. Deaths were related to cardiac (4 cases), respiratory (5 cases), pulmonary embolus (2 cases), and sepsis (1 case) etiologies, and a perforated gastric ulcer (1 case). Complication rates did not differ based on patient age or whether fusion was performed. Minimally invasive procedures were associated with fewer complications and fewer new neurological deficits (p = 0.01 and 0.03, respectively).

Conclusions

The results from this analysis of the SRS M&M database provide surgeons with useful information for preoperative counseling of patients contemplating surgical intervention for symptomatic degenerative lumbar stenosis.
Neurological manifestations, imaging characteristics, and surgical outcome of intraspinal osteochondroma
Authors: Lotfinia Iraj , Vahedi Payman , Tubbs R. Shane , Ghavame Mostafa , Meshkini Ali
Published: June 2010

Object

Spinal osteochondromas (OCs) are rare and can originate as solitary lesions or in the context of hereditary multiple exostoses. Concurrent spinal cord compression is a very rare entity. The purpose of this study was to evaluate the authors' 10-year experience with the imaging characteristics and surgical outcome in patients with symptomatic spinal OC.

Methods

Between 1997 and 2007, 8 consecutive cases of symptomatic intraspinal OC with documented spinal cord compression were treated surgically. These patients were analyzed with regard to presentation, imaging, and outcome. The relevant English literature was reviewed using MEDLINE and Google search engines.

Results

Three patients had cervical, 2 had thoracic, and 3 had lumbar lesions. Classic MR imaging characteristics were rarely found. Multiple hereditary exostoses were equally responsible for cervical, thoracic, and lumbar lesions (33%). The origin of the lesion was from the pedicle (25%), lamina (25%), vertebral body (25%), and superior or inferior facets (25%). A posterior approach to the spine was used in 6 patients, and a combined anterior and posterior approach with fusion was performed for 2 thoracic lesions. Surgical outcome was satisfactory in 75% of patients. The prognosis was poor in the patients with thoracic lesions.

Conclusions

In the authors' experience, early detection and surgical removal in cases of symptomatic spinal OC is a key element for the best outcome. Posterior approaches are generally sufficient. The chronicity of symptoms may limit functional recovery postoperatively, especially with cervical and thoracic lesions.
Entropy-Based Method of Choosing the Decomposition Level in Wavelet Threshold De-noising
Authors: Sang Yan-Fang , Wang Dong , Wu Ji-Chun
Published: June 2010

In this paper, the energy distributions of various noises following normal, log-normal and Pearson-III distributions are first described quantitatively using the wavelet energy entropy (WEE), and the results are compared and discussed. Then, on the basis of these analytic results, a method for use in choosing the decomposition level (DL) in wavelet threshold de-noising (WTD) is put forward. Finally, the performance of the proposed method is verified by analysis of both synthetic and observed series. Analytic results indicate that the proposed method is easy to operate and suitable for various signals. Moreover, contrary to traditional white noise testing which depends on “autocorrelations”, the proposed method uses energy distributions to distinguish real signals and noise in noisy series, therefore the chosen DL is reliable, and the WTD results of time series can be improved.
Assessment of Environmental Distribution of Lead in Some Municipalities of South-Eastern Nigeria
Authors: Nduka John Kanayochukwu , Orisakwe Orish Ebere
Published: June 2010

Lead (Pb) levels were measured in roadside surface soils, dust particles and rain water samples from the urban cities of Enugu, Awka, Onitsha, Nnewi, Aba, Port Harcourt and Warri in Southern Nigeria in 2007 and 2008. Samples were collected during the dry season, while rain water samples were collected during the early rain (April–June), mid rain (July–August) and late rain seasons (September–October) for the two years. Soil samples were collected from traffic congested roads, dust was collected by tying a plastic basin on a pole 1.5 m above ground level and leaving it for 45 days. Rain samples were collected from three equidistant points. Samples were analyzed by AAS. The highest soil Pb of 120.00 ± 0.00 and 80.36 ± 0.00 mg/kg were reported in Onitsha for 2007 and 2008, respectively. Nnewi showed 33.40 ± 0.01 and 4,238.29 ± 0.00 mg/kg for 2007 and 2008. Aba had 22.56 ± 0.01 and 21.28 ± 0.00 mg/kg for 2007 and 2008. Higher concentrations were recorded for Nnewi and Port Harcourt in 2008 than in 2007. Enugu had more in 2007 while Awka had more in 2008. Dust Pb ranged from 0.13–0.49 mg/kg and 0.15–0.47 mg/kg for 2007 and 2008, respectively. Rain samples had the least Pb concentration, ranging from 0.103 ± 0.000 to 0.163 ± 0.046 mg/L. We may conclude that Nigerians are exposed to environmental Pb.
Recent Applications of Fluorescence Recovery after Photobleaching (FRAP) to Membrane Bio-Macromolecules
Authors: Rayan Gamal , Guet Jean-Erik , Taulier Nicolas , Pincet Frederic , Urbach Wladimir
Published: June 2010

This review examines some recent applications of fluorescence recovery after photobleaching (FRAP) to biopolymers, while mainly focusing on membrane protein studies. Initially, we discuss the lateral diffusion of membrane proteins, as measured by FRAP. Then, we talk about the use of FRAP to probe interactions between membrane proteins by obtaining fundamental information such as geometry and stoichiometry of the interacting complex. Afterwards, we discuss some applications of FRAP at the cellular level as well as the level of organisms. We conclude by comparing diffusion coefficients obtained by FRAP and several other alternative methods.
Climate Change and Tourism in the Great Lakes Region: A Summary of Risks and Opportunities
Authors: Dawson Jackie , Scott Daniel
Published: June 2010

An integral component of the tourism/recreation sector in the Great Lakes region of Canada is climate. Climate defines the length and quality of tourism seasons and associated levels of participation (i.e., natural seasonality) and it affects the natural resource base that many forms
of tourism depend upon. Changes in natural seasonality and the environment induced by climate change could have substantial implications for the sustainability of specific tourism sectors and the communities that depend on them. This article summarizes existing literature to provide an overview
of the risks and opportunities climate change poses for the tourism/recreation sector across the entire Great Lakes region. Winter tourism is projected to be negatively impacted in the region, with reductions in season length for skiing, snowmobiling, and ice fishing. Warm weather tourism
is projected to benefit from climate change through extended seasons for major activities such as golfing, park visitation, camping, beach use, and boating. The differential effects of climate change in the Great Lakes region will alter the competiveness of tourism sectors. Determining how
tourism operators and communities will need to adapt to supply- and demand-side changes in order to reduce the risk and take advantage of new opportunities in a sustainable manner remains an important area for future inquiry.
Fine Mapping and Candidate Gene Discovery of the Soybean Mosaic Virus Resistance Gene, Rsv4
Authors: Maroof M. A. Saghai , Tucker Dominic M. , Skoneczka Jeffrey A. , Bowman Brian C. , Tripathy Sucheta , Tolin Sue A.
Published: June 2010

Soybean mosaic virus (SMV) is a prevalent virus infecting soybean (Glycine max L. Merr) worldwide. The incorporation of Rsv4, conferring resistance to all currently known strains in the United States, can assist in creating durable virus resistance in soybean. Additionally, lines heterozygous at the Rsv4 locus often express a late susceptible phenotype, showing symptoms only in mid to late vegetative growth. In this study the whole‐genome shotgun sequence (WGS) of soybean was utilized for fine mapping and examining potential Rsv4 gene candidates in two populations. Six markers, designed from the WGS, were used to localize Rsv4 in the same, 1.3‐cM region in both mapping populations, a physical interval of less than 100 kb on chromosome 2. This region contained no sequences previously related to virus resistance, namely nucleotide binding site‐leucine rich repeat gene sequences or eukaryotic translation initiation factors. Instead, sequence analysis revealed several predicted transcription factors and unknown protein products. We conclude that Rsv4 likely belongs to a new class of resistance genes that interfere with viral infection and cell‐to‐cell movement, and delay vascular movement.
Rapid Genome‐wide Single Nucleotide Polymorphism Discovery in Soybean and Rice via Deep Resequencing of Reduced Representation Libraries with the Illumina Genome Analyzer
Authors: Deschamps Stéphane , la Rota Mauricio , Ratashak Jeffrey P. , Biddle Phyllis , Thureen Dean , Farmer Andrew , Luck Stanley , Beatty Mary , Nagasawa Nobuhiro , Michael Leah , Llaca Victor , Sakai Hajime , May Gregory , Lightner Jonathan , Campbell Matthew A.
Published: June 2010

Massively parallel sequencing platforms have allowed for the rapid discovery of single nucleotide polymorphisms (SNPs) among related genotypes within a species. We describe the creation of reduced representation libraries (RRLs) using an initial digestion of nuclear genomic DNA with a methylation‐sensitive restriction endonuclease followed by a secondary digestion with the 4bp‐restriction endonuclease DpnII. This strategy allows for the enrichment of hypomethylated genomic DNA, which has been shown to be rich in genic sequences, and the digestion with DpnII serves to increase the number of common loci resequenced between individuals. Deep resequencing of these RRLs performed with the Illumina Genome Analyzer led to the identification of 2618 SNPs in rice and 1682 SNPs in soybean for two representative genotypes in each of the species. A subset of these SNPs was validated via Sanger sequencing, exhibiting validation rates of 96.4 and 97.0%, in rice (Oryza sativa) and soybean (Glycine max), respectively. Comparative analysis of the read distribution relative to annotated genes in the reference genome assemblies indicated that the RRL strategy was primarily sampling within genic regions for both species. The massively parallel sequencing of methylation‐sensitive RRLs for genome‐wide SNP discovery can be applied across a wide range of plant species having sufficient reference genomic sequence.
Analysis of Genes Underlying Soybean Quantitative Trait Loci Conferring Partial Resistance to Phytophthora sojae
Authors: Wang Hehe , Waller LaChelle , Tripathy Sucheta , St. Martin Steven K. , Zhou Lecong , Krampis Konstantinos , Tucker Dominic M. , Mao Yongcai , Hoeschele Ina , Saghai Maroof M.A. , Tyler Brett M. , Dorrance Anne E.
Published: June 2010

Few quantitative trait loci (QTL) have been mapped for the expression of partial resistance to Phytophthora sojae in soybean and very little is known about the molecular mechanisms that contribute to this trait. Therefore, the objectives of this study were to identify additional QTL conferring resistance to P. sojae and to identify candidate genes that may contribute to this form of defense. QTL on chromosomes 12, 13, 14, 17, and 19, each explaining 4 to 7% of the phenotypic variation, were identified using 186 RILs from a cross of the partially resistant cultivar ‘Conrad’ and susceptible cultivar ‘Sloan’ through composite interval mapping. Microarray analysis identified genes with significant differences in transcript abundances between Conrad and Sloan, both constitutively and following inoculation. Of these genes, 55 mapped to the five QTL regions. Ten genes encoded proteins with unknown functions, while the others encode proteins related to defense or physiological traits. Seventeen genes within the genomic region that encompass the QTL were selected and their transcript abundance was confirmed by quantitative reverse transcription polymerase chain reaction (qRT‐PCR). These results suggest a complex QTL‐mediated resistance network. This study will contribute to soybean resistance breeding by providing additional QTL for marker‐assisted selection as well as a list of candidate genes which may be manipulated to confer resistance.
PREDICTION OF THE ANTICLASTIC SHAPE CHANGES OF HYBRID COMPOSITE MATERIAL
Authors: Baikovs Andris , Rocēns Kārlis
Published: June 2010

In search of structurally better and aesthetically more attractive solutions of the erection of various structures, non‐standard anticlastic elements are used more frequently. Therefore preservation of the initial shape of timber composite material sheets by using of reinforced plastic reinforcement has been investigated. Calculation model for determination of the thickness of rational reinforcement anticlastic sheet, which provides change of the original bending radius under variable moisture conditions (Baikovs and Rocens, 2006) within the limits of preferable intervals is developed by authors and using finite element method, calculations and modelling of sheet deformations are carried out with software package ANSYS v.11 (henceforth FEM) and by developed analytical method. Comparative research of the results calculated with the FEM and developed calculation model showed that the difference between results in the three cases investigated, when the composite timber material is reinforced on the top, bottom and both sides for the most of the cases does not exceed 3.3%. An opportunity to provide the original shape of anticlastic timber composite material sheets by using glass fibre reinforced plastic reinforcement under variable moisture conditions and not exceeding the difference of 5% has been demonstrated. Santrauka Ieškant ivairiu konstrukciju statiniu konstrukciškai geresniu ir estetiškai patrauklesniu sprendiniu, dažniausiai naudojami nestandartiniai antiklastiniai elementai. Todel buvo tyrinetas medienos kompozitines medžiagos lakštu pradinio pavidalo išsaugojimas naudojant sustiprinta plastiko armatūra. Skaičiuojamasis modelis, padedantis nustatyti racionaliai armuoto antiklastinio lakšto stori, kuris pakeičia pradini lenkimo spinduli kintamomis dregmes salygomis (Baikovs, Rocens 2006) tarp priimtinu intervalu ribu, yra sukurtas autoriu ir, taikant baigtiniu elementu metoda, lakšto deformaciju skaičiavimai bei modeliavimas atlikti kompiuteriniu programu paketu ANSYS v. 11 (toliau ‐ FEM) ir pagal sukurta analitini metoda. Rezultatu, apskaičiuotu su FEM ir pagal sukurta analitini modeli, lyginamasis tyrimas parode, kad skirtumas tarp triju tirtu atveju, kai medienos kompozitine medžiaga yra armuota viršuje, apačioje ir iš abieju pusiu, rezultatai daugeliu atveju neviršija 3,3%. Parodyta galimybe suteikti originalu pavidala antiklastiniams medienos kompozitiniams lakštams naudojant stiklo pluoštu sustiprinto plastiko armatūra ivairiomis dregmes salygomis ir neviršijant 5% skirtumo.