854 resultados para stage-constructed embankment
Resumo:
The object of this article is to estimate demand elasticities for a basket of staple food important for providing the caloric needs of Brazilian households. These elasticities are useful in the measurement of the impact of structural reforms on poverty. A two-stage demand system was constructed, based on data from Household Expenditure Surveys (POF) produced by IBGE (The Brazilian Bureau of Statistics) in 1987/88 and 1995/96. We have used panel data to estimate the model, and have calculated income, own-price, and cross-price elasticities for eight groups of goods and services and, in the second stage, for 11 sub groups of staple food products. We estimated those elasticities for the whole sample of consumers and for two income groups.
Resumo:
Vertebroplasty and kyphoplasty have been reported to alter the mechanical behavior of the treated and adjacent-level segments, and have been suggested to increase the risk for adjacent-level fractures. The intervertebral disc (IVD) plays an important role in the mechanical behavior of vertebral motion segments. Comparisons between normal and degenerative IVD motion segments following cement augmentation have yet to be reported. A microstructural finite element model of a degenerative IVD motion segment was constructed from micro-CT images. Microdamage within the vertebral body trabecular structure was used to simulate a slightly (I = 83.5% of intact stiffness), moderately (II = 57.8% of intact stiffness), and severely (III = 16.0% of intact stiffness) damaged motion segment. Six variable geometry single-segment cement repair strategies (models A-F) were studied at each damage level (I-III). IVD and bone stresses, and motion segment stiffness, were compared with the intact and baseline damage models (untreated), as well as, previous findings using normal IVD models with the same repair strategies. Overall, small differences were observed in motion segment stiffness and average stresses between the degenerative and normal disc repair models. We did however observe a reduction in endplate bulge and a redistribution in the microstructural tissue level stresses across both endplates and in the treated segment following early stage IVD degeneration. The cement augmentation strategy placing bone cement along the periphery of the vertebra (model E) proved to be the most advantageous in treating the degenerative IVD models by showing larger reductions in the average bone stresses (vertebral and endplate) as compared to the normal IVD models. Furthermore, only this repair strategy, and the complete cement fill strategy (model F), were able to restore the slightly damaged (I) motion segment stiffness above pre-damaged (intact) levels. Early stage IVD degeneration does not have an appreciable effect in motion segment stiffness and average stresses in the treated and adjacent-level segments following vertebroplasty and kyphoplasty. Placing bone cement in the periphery of the damaged vertebra in a degenerative IVD motion segment, minimizes load transfer, and may reduce the likelihood of adjacent-level fractures.
Resumo:
OBJECTIVES: To assess the accuracy of high-resolution (HR) magnetic resonance imaging (MRI) in diagnosing early-stage optic nerve (ON) invasion in a retinoblastoma cohort. METHODS: This IRB-approved, prospective multicenter study included 95 patients (55 boys, 40 girls; mean age, 29 months). 1.5-T MRI was performed using surface coils before enucleation, including spin-echo unenhanced and contrast-enhanced (CE) T1-weighted sequences (slice thickness, 2 mm; pixel size <0.3 × 0.3 mm(2)). Images were read by five neuroradiologists blinded to histopathologic findings. ROC curves were constructed with AUC assessment using a bootstrap method. RESULTS: Histopathology identified 41 eyes without ON invasion and 25 with prelaminar, 18 with intralaminar and 12 with postlaminar invasion. All but one were postoperatively classified as stage I by the International Retinoblastoma Staging System. The accuracy of CE-T1 sequences in identifying ON invasion was limited (AUC = 0.64; 95 % CI, 0.55 - 0.72) and not confirmed for postlaminar invasion diagnosis (AUC = 0.64; 95 % CI, 0.47 - 0.82); high specificities (range, 0.64 - 1) and negative predictive values (range, 0.81 - 0.97) were confirmed. CONCLUSION: HR-MRI with surface coils is recommended to appropriately select retinoblastoma patients eligible for primary enucleation without the risk of IRSS stage II but cannot substitute for pathology in differentiating the first degrees of ON invasion. KEY POINTS: • HR-MRI excludes advanced optic nerve invasion with high negative predictive value. • HR-MRI accurately selects patients eligible for primary enucleation. • Diagnosis of early stages of optic nerve invasion still relies on pathology. • Several physiological MR patterns may mimic optic nerve invasion.
Resumo:
Phase I was initiated as a result of internal Iowa Department of Transportation (Iowa DOT) studies that raised concerns about the quality of embankments being constructed. Some large embankments have recently developed slope stability problems. In addition, pavement roughness has been noted shortly after roads were opened to traffic. This raised the question as to whether the current Iowa DOT embankment construction specifications are adequate. The primary objective of Phase I was to evaluate the quality of embankments being constructed under the current Iowa DOT specifications. The project was initiated in May 1997 with a tour of several embankment projects being constructed around the state. At each of these projects the resident construction engineer, field inspector, and contractor were interviewed with respect to their opinion of the current specifications. From construction observations and discussion during these visits it became obvious that there were problems with the current embankment construction specifications. Six embankment projects were selected for in-depth analysis and to represent the full range of soil types being used across the state. The results of Phase I field and laboratory construction testing and observations and post construction testing are presented in this report. Overall evaluation of the results of Phase I indicate that Iowa is not consistently obtaining a quality embankment constructed under the current Iowa DOT specifications. Based on these results, recommendations are made for Phase II to evaluate alternative specifications and develop rapid field methods for compaction control and soil identification.
Potential-Scour Assessments and Estimates of Maximum Scour at Selected Bridges in Iowa, HR-344, 1995
Resumo:
This report presents the results of potential-scour assessments at 130 bridges and estimates of maximum scour at 10 bridges, in Iowa. All of the bridges evaluated in the study are constructed bridges (not culverts) that are sites of active or discontinued streamflow-gaging stations and peak-stage measurement sites. The period of the study was from October 1991 to September 1994. The potential-scour assessments were made using a potential-scour index developed by the U.S. Geological Survey for a study in Tennessee. Higher values of the index suggest a greater likelihood of scour-related problems occurring at a bridge. The estimates of maximum scour were made using scour equations recommended by the Federal Highway Administration. In this study, the long term aggradation or degradation that occurred during the period of streamflow data collection at each site was evaluated. Although the abutment-scour equation predicted deep scour holes at many of the sites, the only significant abutment scour that was measured was erosion of the embankment at the left abutment at one bridge after a flood.
Resumo:
Culverts are common means to convey flow through the roadway system for small streams. In general, larger flows and road embankment heights entail the use of multibarrel culverts (a.k.a. multi-box) culverts. Box culverts are generally designed to handle events with a 50-year return period, and therefore convey considerably lower flows much of the time. While there are no issues with conveying high flows, many multi-box culverts in Iowa pose a significant problem related to sedimentation. The highly erosive Iowa soils can easily lead to the situation that some of the barrels can silt-in early after their construction, becoming partially filled with sediment in few years. Silting can reduce considerably the capacity of the culvert to handle larger flow events. Phase I of this Iowa Highway Research Board project (TR-545) led to an innovative solution for preventing sedimentation. The solution was comprehensively investigated through laboratory experiments and numerical modeling aimed at screening design alternatives and testing their hydraulic and sediment conveyance performance. Following this study phase, the Technical Advisory Committee suggested to implement the recommended sediment mitigation design to a field site. The site selected for implementation was a 3-box culvert crossing Willow Creek on IA Hwy 1W in Iowa City. The culvert was constructed in 1981 and the first cleanup was needed in 2000. Phase II of the TR 545 entailed the monitoring of the site with and without the selfcleaning sedimentation structure in place (similarly with the study conducted in laboratory). The first monitoring stage (Sept 2010 to December 2012) was aimed at providing a baseline for the operation of the as-designed culvert. In order to support Phase II research, a cleanup of the IA Hwy 1W culvert was conducted in September 2011. Subsequently, a monitoring program was initiated to document the sedimentation produced by individual and multiple storms propagating through the culvert. The first two years of monitoring showed inception of the sedimentation in the first spring following the cleanup. Sedimentation continued to increase throughout the monitoring program following the depositional patterns observed in the laboratory tests and those documented in the pre-cleaning surveys. The second part of Phase II of the study was aimed at monitoring the constructed self-cleaning structure. Since its construction in December 2012, the culvert site was continuously monitored through systematic observations. The evidence garnered in this phase of the study demonstrates the good performance of the self-cleaning structure in mitigating the sediment deposition at culverts. Besides their beneficial role in sediment mitigation, the designed self-cleaning structures maintain a clean and clear area upstream the culvert, keep a healthy flow through the central barrel offering hydraulic and aquatic habitat similar with that in the undisturbed stream reaches upstream and downstream the culvert. It can be concluded that the proposed self-cleaning structural solution “streamlines” the area upstream the culvert in a way that secures the safety of the culvert structure at high flows while producing much less disturbance in the stream behavior compared with the current constructive approaches.
Resumo:
Background: As the long-term efficacy of stereotactic body radiation therapy (SBRT) becomes established and other prostate cancer treatment approaches are refined and improved, examination of quality of life (QOL) following prostate cancer treatment is critical in driving both patient and clinical treatment decisions. We present the first study to compare QOL after SBRT and radical prostatectomy, with QOL assessed at approximately the same times pre- and post-treatment and using the same validated QOL instrument. Methods: Patients with clinically localized prostate cancer were treated with either radical prostatectomy (n = 123 Spanish patients) or SBRT (n = 216 American patients). QOL was assessed using the Expanded Prostate Cancer Index Composite (EPIC) grouped into urinary, sexual, and bowel domains. For comparison purposes, SBRT EPIC data at baseline, 3 weeks, 5, 11, 24, and 36 months were compared to surgery data at baseline, 1, 6, 12, 24,and 36 months. Differences in patient characteristics between the two groups were assessed using Chi-squared tests for categorical variables and t-tests for continuous variables. Generalized estimating equation (GEE) models were constructed for each EPIC scale to account for correlation among repeated measures and used to assess the effect of treatment on QOL. Results: The largest differences in QOL occurred in the first 16 months after treatment, with larger declines following surgery in urinary and sexual QOL as compared to SBRT, and a larger decline in bowel QOL following SBRT as compared to surgery. Long-term urinary and sexual QOL declines remained clinically significantly lower for surgery patients but not for SBRT patients. Conclusions: Overall, these results may have implications for patient and physician clinical decision making which are often influenced by QOL. These differences in sexual, urinary and bowel QOL should be closely considered in selecting the right treatment, especially in evaluating the value of non-invasive treatments, such as SBRT.
Resumo:
Background: As the long-term efficacy of stereotactic body radiation therapy (SBRT) becomes established and other prostate cancer treatment approaches are refined and improved, examination of quality of life (QOL) following prostate cancer treatment is critical in driving both patient and clinical treatment decisions. We present the first study to compare QOL after SBRT and radical prostatectomy, with QOL assessed at approximately the same times pre- and post-treatment and using the same validated QOL instrument. Methods: Patients with clinically localized prostate cancer were treated with either radical prostatectomy (n = 123 Spanish patients) or SBRT (n = 216 American patients). QOL was assessed using the Expanded Prostate Cancer Index Composite (EPIC) grouped into urinary, sexual, and bowel domains. For comparison purposes, SBRT EPIC data at baseline, 3 weeks, 5, 11, 24, and 36 months were compared to surgery data at baseline, 1, 6, 12, 24,and 36 months. Differences in patient characteristics between the two groups were assessed using Chi-squared tests for categorical variables and t-tests for continuous variables. Generalized estimating equation (GEE) models were constructed for each EPIC scale to account for correlation among repeated measures and used to assess the effect of treatment on QOL. Results: The largest differences in QOL occurred in the first 1-6 months after treatment, with larger declines following surgery in urinary and sexual QOL as compared to SBRT, and a larger decline in bowel QOL following SBRT as compared to surgery. Long-term urinary and sexual QOL declines remained clinically significantly lower for surgery patients but not for SBRT patients. Conclusions: Overall, these results may have implications for patient and physician clinical decision making which are often influenced by QOL. These differences in sexual, urinary and bowel QOL should be closely considered in selecting the right treatment, especially in evaluating the value of non-invasive treatments, such as SBRT.
Resumo:
Dans le contexte actuel de l’éducation au Québec où la réforme des programmes de formation des jeunes appelle un renouvellement des pratiques d’enseignement, notre recherche s’intéresse au développement de la dimension didactique de la pratique liée à l’enseignement des mathématiques qui est considéré comme l’un des éléments clés des nouvelles orientations. Nous abordons la question par le biais de la collaboration de formation initiale pour l’enseignement des mathématiques au primaire qui se vit en stage entre des praticiennes en exercice et en formation et une didacticienne des mathématiques. Cette rencontre sur le terrain des stages au primaire entre praticiennes et didacticienne, longtemps réclamée et rendue possible à l’UQAT , nous a amené à formuler une première question de recherche touchant ce qui se construit à travers les échanges de ces partenaires de la formation au cours des supervisions pédagogiques conjointes qui les réunissent en stage. Nous avons cadré ce questionnement à partir des balises théoriques de la didactique professionnelle qui proposent modèle et concepts pour expliciter l’activité professionnelle et traiter des phénomènes de développement des compétences professionnelles en contexte de travail et de formation. La didactique professionnelle attribue un rôle essentiel à la communauté de pratique et au processus d’analyse de l’expérience dans le développement professionnel des novices et dans l’explicitation d’un savoir d’action jugé pertinent et reconnu. Nous y faisons donc appel pour poser le potentiel que représentent les échanges issus de la collaboration quant à leur contribution à l’établissement d’un savoir de référence pour l’enseignement des mathématiques. La didactique professionnelle propose également le recours au concept de schème pour décrire l’activité professionnelle et à l’idée de concepts organisateurs comme élément central de l’activité et comme variable de la situation professionnelle concernée. Nous recourons à ces mêmes concepts pour expliciter le savoir de référence pour l’enseignement des mathématiques qui émerge à travers les échanges des partenaires de la formation. Dans le cadre d’une étude de cas, nous nous sommes intéressée aux échanges qui se déroulent entre une stagiaire qui effectue son troisième et avant dernier stage , l’enseignante-associée qui la reçoit et la chercheure-didacticienne qui emprunte le rôle de superviseure universitaire. Les échanges recueillis sont issus de trois cycles de supervision conjointe qui prennent la forme de rencontres de préparation des situations d’enseignement de mathématique; d’observation en classe des séances d’enseignement pilotées par la stagiaire auprès de ses élèves; et des rencontres consacrées à l’analyse des situations d’enseignement observées et de l’activité mise en œuvre par la stagiaire. Ainsi les objets de discussion relevés par les différents partenaires de la formation et la négociation de sens des situations professionnelles vécues et observées sont analysés de manière à rendre visibles les constituants de l’activité professionnelle qui sont jugés pertinents par la triade de formation. Dans un deuxième temps, en partant de cette première analyse, nous dégageons les concepts organisateurs des situations professionnelles liées à l’enseignement des mathématiques qui sont pris en compte par la triade de formation et qui constituent des variables de la situation professionnelle. Les constituants de l’activité et des situations professionnelles qui résultent de cette analyse sont envisagés en tant que représentations collectives qui se révèlent à travers les échanges de la triade de formation. Parce que ces représentations se sont trouvées partagées, négociées dans le cadre des supervisions pédagogiques, elles sont envisagées également en tant que savoir de référence pour cette triade de formation. Les échanges rendus possibles entre les praticiennes et la didacticienne placent ce savoir de référence dans une dynamique de double rationalité pratique et didactique. Enfin, partant de l’apport déterminant de la communauté de pratique et de formation de même que du savoir de référence que cette dernière reconnait comme pertinent dans le développement professionnel des novices, les résultats de cette recherches peuvent contribuer à réfléchir la formation des futures enseignantes en stage en ce qui a trait à l’enseignement des mathématiques au primaire.
Stage, Grade and Behavior of Bladder Urothelial Carcinoma Defined by the MicroRNA Expression Profile
Resumo:
Purpose: We identified miRNA expression profiles in urothelial carcinoma that are associated with grade, stage, and recurrence-free and disease specific survival. Materials and Methods: The expression of 14 miRNAs was evaluated by quantitative reverse transcriptase-polymerase chain reaction in surgical specimens from 30 patients with low grade, noninvasive (pTa) and 30 with high grade, invasive (pT2-3) urothelial carcinoma. Controls were normal bladder tissue from 5 patients who underwent surgical treatment for benign prostatic hyperplasia. Endogenous controls were RNU-43 and RNU-48. miRNA profiles were compared and Kaplan-Meier curves were constructed to analyze disease-free and disease specific survival. Results: miR-100 was under expressed in 100% of low grade pTa specimens (p <0.001) and miR-10a was over expressed in 73.3% (p <0.001). miR-21 and miR-205 were over expressed in high grade pT2-3 disease (p = 0.02 and <0.001, respectively). The other miRNAs were present at levels similar to those of normal bladder tissue or under expressed in each tumor group. miR-21 over expression (greater than 1.08) was related to shorter disease-free survival in patients with low grade pTa urothelial carcinoma. Higher miR-10a levels (greater than 2.30) were associated with shorter disease-free and disease specific survival in patients with high grade pT2-3 urothelial carcinoma. Conclusions: Four miRNAs were differentially expressed in the 2 urothelial carcinoma groups. miR-100 and miR-10a showed under expression and over expression, respectively, in low grade pTa tumors. miR-21 and miR-205 were over expressed in pT2-3 disease. In addition, miR-10a and miR-21 over expression was associated with shorter disease-free and disease specific survival. miRNAs could be incorporated into the urothelial carcinoma molecular pathway. These miRNAs could also serve as new diagnostic or prognostic markers and new target drugs.
Resumo:
Hepatocellular carcinoma (HCC) has been ranked as the top cause of death due to neoplasm malignancy in Taiwan for years. The high incidence of HCC in Taiwan is primarily attributed to high prevalence of hepatitis viral infection. Screening the subjects with liver cirrhosis for HCC was widely recommended by many previous studies. The latest practice guideline for management of HCC released by the American Association for the Study of Liver Disease (AASLD) in 2005 recommended that the high risk groups, including cirrhotic patients, chronic HBV/HCV carriers, and subjects with family history of HCC and etc., should undergo surveillance.^ This study aims to investigate (1) whether the HCC screening program can prolong survival period of the high risk group, (2) what is the incremental cost-effectiveness ratio of the HCC screening program in Taiwan, as compared with a non-screening strategy from the payer perspective, (3) which high risk group has the lowest ICER for the HCC screening program from the insurer's perspective, in comparison with no screening strategy of each group, and (4) the estimated total cost of providing the HCC screening program to all high risk groups.^ The high risk subjects in the study were identified from the communities with high prevalence of hepatitis viral infection and classified into three groups (cirrhosis group, early cirrhosis group, and no cirrhosis group) at different levels of risk to HCC by status of liver disease at the time of enrollment. The repeated ultrasound screenings at an interval of 3, 6, and 12 months were applied to cirrhosis group, early cirrhosis group, and no cirrhosis group, respectively. The Markov-based decision model was constructed to simulate progression of HCC and to estimate the ICER for each group of subjects.^ The screening group had longer survival in the statistical results and the model outcomes. Owing to the low HCC incidence rate in the community-based screening program, screening services only have limited effect on survival of the screening group. The incremental cost-effectiveness ratio of the HCC screening program was $3834 per year of life saved, in comparison with the non-screening strategy. The estimated total cost of each group from the screening model over 13.5 years approximately consumes 0.13%, 1.06%, and 0.71% of total amount of adjusted National Health Expenditure from Jan 1992 to Jun 2005. ^ The subjects at high risk of developing HCC to undergo repeated ultrasound screenings had longer survival than those without screening, but screening was not the only factor to cause longer survival in the screening group. The incremental cost-effectiveness ratio of the 2-stage community-based HCC screening program in Taiwan was small. The HCC screening program was worthy of investment in Taiwan. In comparison with early cirrhosis group and no cirrhosis group, cirrhosis group has the lowest ICER when the screening period is less than 19 years. The estimated total cost of providing the HCC screening program to all high risk groups consumes approximately 1.90% of total amount of adjusted 13.5-year NHE in Taiwan.^
Resumo:
This study provides support to the characteristics of participatory and anticipatory stages in secondary school pupils’ abstraction of mathematical conceptions. We carried out clinical task-based interviews with 71 secondary-school pupils to obtain evidence of the different constructed mathematical conceptions (Participatory Stage) and how they were used (Anticipatory Stage). We distinguish two moments in the Participatory Stage based on the coordination of information from particular cases by activity-effect reflection which, in some cases, lead to a change of focus enabling secondary-school pupils to achieve a reorganization of their knowledge. We argue that (a) the capacity of perceiving regularities in sets of particular cases is a characteristic of activity-effect reflection in the abstraction of mathematical conceptions in secondary school, and (b) the coordination of information by pupils provides opportunities for changing the attention-focus from the particular results to the structure of properties.
Resumo:
Sugarcane moth borers are a diverse group of species occurring in several genera, but predominately within the Noctuidae and Pyraloidea. They cause economic loss in sugarcane and other crops through damage to stems and stalks by larval boring. Partial sequence data from two mitochondrial genes, COII and 16S, were used to construct a molecular phylogeny based on 26 species from ten genera and six tribes. The Noctuidae were found to be monophyletic, providing molecular support for the taxonomy within this subfamily. However, the Pyraloidea are paraphyletic, with the noctuids splitting Galleriinae and Schoenobiinae from the Crambinae. This supports the separation of the Pyralidae and Crambinae, but does not support the concept of the incorporation of the Schoenobiinae in the Crambidae. Of the three crambine genera examined, Diatraea was monophyletic, Chilo paraphyletic, and Eoreuma was basal to the other two genera. Within the Noctuidae, Sesamia and Bathytricha were monophyletic, with Busseola basal to Bathytricha. Many species in this study (both noctuids and pyraloids) had different biotypes within collection localities and across their distribution; however the individual biotypes were not phylogenetically informative. These data highlight the need for taxonomic revisions at all taxon levels and provide a basis for the development of DNA-based diagnostics for rapidly identifying many species at any developmental stage. This ability is vital, as the species are an incursion threat to Australia and have the potential to cause significant losses to the sugar industry.
Resumo:
The aim of this study was to evaluate dosing schedules of gentamicin in patients with end-stage renal disease and receiving hemodialysis. Forty-six patients were recruited who received gentamicin while on hemodialysis. Each patient provided approximately 4 blood samples at various times before and after dialysis for analysis of plasma gentamicin concentrations. A population pharmacokinetic model was constructed using NONMEM (version 5). The clearance of gentamicin during dialysis was 4.69 L/h and between dialysis was 0.453 L/h. The clearance between dialysis was best described by residual creatinine clearance (as calculated using the Cockcroft and Gault equation), which probably reflects both lean mass and residual clearance mechanisms. Simulation from the final population model showed that predialysis dosing has a higher probability of achieving target maximum concentration (C-max) concentrations (> 8 mg/L) within acceptable exposure limits (area under the concentration-time curve [AUC] values > 70 and < 120 mg.h/L per 24 hours) than postdialysis dosing.
Resumo:
This PhD thesis provides a detailed analysis of the role and significance of Irish drama in the Galician cultural context, from the early twentieth century onwards, through scrutiny of key works translated, adapted and mediated for the Galician stage. Drawing primarily on the theoretical framework of Descriptive Translation Studies, informed by Polysystems theory (Toury), Post-colonial Translation, research on processes of cultural translation (Bassnett, Lefevere, Venuti, Aaltonen), as well as careful comparative attention to the specificities of literary, theatrical and cultural context, I examine the factors governing the incorporation, reshaping and reception of twentieth century Irish plays in Galicia in order to produce a cultural history of the representation of Ireland on the Galician stage. Focusing on the five key periods I have identified in the translation/reception of Irish drama in Galicia, as represented in specific versions of plays by Yeats, Synge, O’Casey and McDonagh, my thesis examines in detail the particular linguistic, sociopolitical, theatrical and cultural dimensions of each rewriting and/or restaging in order to uncover the ways in which Irish identity is perceived, constructed and performed in a Galician context. Moving beyond the literary, historical and philological focus of existing studies of the reception of Irish literature and foreign dramatic texts in the Galician system, my own approach draws on Theatre and Performance Studies to attend also to the performative dimension of these processes of cultural adaptation and reception, giving full account of the different agents involved in theatre translation as a rich and complex process of multivalent cultural mediation.