X̄ chart with variable sample size and sampling intervals

Recent theoretical studies have shown that the X̄ chart with variable sampling intervals (VSI) and the X̄ chart with variable sample size (VSS) are quicker than the traditional X̄ chart in detecting shifts in the process. This article considers the X̄ chart with variable sample size and sampling intervals (VSSI). It is assumed that the amount of time the process remains in control has exponential distribution. The properties of the VSSI X̄ chart are obtained using Markov chains. The VSSI X̄ chart is even quicker than the VSI or VSS X̄ charts in detecting moderate shifts in the process.

VSSI X̄ charts with sampling at fixed times

A standard X̄ chart for controlling the process mean takes samples of size n0 at specified, equally-spaced, fixed-time points. This article proposes a modification of the standard X chart that allows one to take additional samples, bigger than n0, between these fixed times. The additional samples are taken from the process when there is evidence that the process mean moved from target. Following the notation proposed by Reynolds (1996a) and Costa (1997) we shortly call the proposed X chart as VSSIFT X chart where VSSIFT means variable sample size and sampling intervals with fixed times. The X chart with the VSSIFT feature is easier to be administered than a standard VSSI X chart that is not constrained to sample at the specified fixed times. The performances of the charts in detecting process mean shifts are comparable. Copyright © 1998 by Marcel Dekker, Inc.

Development of a low-cost mobile mapping system: A South American experience

This paper presents the prototype of a low-cost terrestrial mobile mapping system (MMS) composed of a van, two digital video cameras, two GPS receivers, a notebook computer, and a sound frame synchronisation system. The imaging sensors are mounted as a stereo video camera on top of the vehicle together with the GPS antennae. The GPS receivers and the notebook computer are configured to record data referred to the vehicle position at a planned time interval. This position is subsequently transferred to the road images. This set of equipment and methods provide the opportunity to merge distinct techniques to make topographic maps and also to build georeferenced road image databases. Both vector maps and raster image databases, when integrated appropriately, can give spatial researchers and engineers a new technique whose application may realise better planning and analysis related to the road environment. The experimental results proved that the MMS developed at the São Paulo State University is an effective approach to inspecting road pavements, to map road marks and traffic signs, electric power poles, telephone booths, drain pipes, and many other applications important to people's safety and welfare. A small number of wad images have already been captured by the prototype as a consequence of its application in distinct projects. An efficient organisation of those images and the prompt access to them justify the need for building a georeferenced image database. By expanding it, both at the hardware and software levels, it is possible for engineers to analyse the entire road environment on their office computers.

Spontaneous resolution rates of vesicoureteral reflux in Brazilian children: A 30-year experience

Objective: We evaluated clinical characteristics of primary vesicoureteral reflux (VLJR) in infants in a 30-year period in Brazil with special reference to the relation of renal parenchymal damage to urinary tract infection and gender. Materials and Methods: From 1975 through 2005, 417 girls (81.6%) and 94 boys (18.4%) with all grades of reflux were retrospectively reviewed. Patients were categorized by the worst grade of reflux, maintained on antibiotic prophylaxis and underwent yearly voiding cystourethrography until the reflux was resolved. VUR was considered resolved when a follow-up cystogram demonstrated no reflux. Surgical correction was recommended for those who fail medical therapy, severe renal scarring or persistent VUR. Results: Grades I to V VUR resolved in 87.5%, 77.6%, 52.8%, 12.2% and 4.3%, respectively. Renal scars were present at presentation in 98 patients (19.2%). Neither gender nor bilaterality versus unilaterality was a helpful predictor of resolution. The significant difference was found among the curves using the log rank (p < 0.001) or Wilcoxon (p < 0.001) test. Conclusion: Despite the current use of screening prenatal ultrasound, many infants are still diagnosed as having vesicoureteral reflux only after the occurrence of urinary tract infection in our country. Scarring may be associated to any reflux grade and it may be initially diagnosed at any age but half of the scars are noted with higher grades of reflux (IV and V). The incidence of reflux related morbidity in children has significantly diminished over the last three decades.

Exfoliative cytology of the oral mucosa: Comparison of two collection methods

This study compared the sampling efficacy cia cytobrush and metal spatula for exfoliative cytology of the oral mucosa. Thirty students with no detectable oral alterations upon clinical examination were submitted to exfoliative cytology of the lateral border of the tongue, using a metal spatula on the left side and a cytobrush on the right side. The smears were stained using the Papanicoiaou technique and evaluated for cellularity, cell type, cell distribution, homogeneity, and cellular distortion, as well as the presence ol mucus, inflammatory infiltrate, and hemorrhage. A statistical test (Z-test) with a 95% confdence interval (Cl) showed a significant difference between the metal spatula and cytobrush in terms of cellularity (p = 0.02) and homogeneity (p = 0.01). No difference between the two methods was observed regarding cell type (p = 0.4, Z-test) or cell distribution for the 95% confidence interval (p = 0.2, Fisher's test). Cell distortion and the presence of mucus were observed in five cases that used the metal spatula and in two cases that used the cytobrush. No hemorrhage or inflammatory infItrate was detected in any of the slides. Based on the results of this study, the cytobrush produced qualitatively better smears in terms of cellularity and homogeneity compared to the metal spatula.

Dental caries experience in children attending an infant oral health program

Aim: To investigate: a) caries experience in 5 year-old children and its relationship to the caries risk evaluation made before 1 year of age; b) compliance of parents to an infant oral health program as well as the abandonment reasons. Methods: Group A (GA) - 242 children (60-71 months old) who stayed in the program and had been enrolled since their first year of life underwent a clinical examination according to the WHO's criteria; their parents/caregivers were interviewed to ascertain their compliance to the program. Group B (GB) - parents of 60 children, who had dropped out of the program, were interviewed to check the reasons of withdrawing. The caries risk classification was based on the file at the first appointment. Chi-square test was used (α=0.05) for statistical analyses. Results: Most of the children were free of caries (71.1%). Caries risk evaluation showed low sensibility (34.3%, 95% CI = 22.4-46.1) and high specificity (74.4%, 95% CI = 67.6-81.2) to caries experience. Sixty-two mothers (25.6%) reported difficulty to follow the guidelines. The main reason for dropping out was changing to similar health services (40.0%). Conclusions: Caries risk in the first year of life was not efficient to predict dental caries experience at 5 years of age. Educational practice should be improved to increase the compliance of the parents to the program.

Correlation between oral health perception and clinical factors in a Brazilian community

Objective: The aim of this study was to analyse associations between self-perception of oral health and relevant clinical, personal and socio-demographic factors in a Brazilian community. Material And Methods: Urban adults living in a city in southern Brazil were interviewerd and examined. Individuals with acute pain and who needed multiple extractions of teeth were excluded. Self-perception and the Oral Health Impact Profile (OHIP-14) were applied to measure the impact of oral conditions on the quality of life. Socio-demographic and clinical indicators were also analysed. Results: The clinical examination revealed a high dental caries experience (DMFT = 18.9) and a high prevalence of periodontal disease. Oral condition was considered normal by 42% of respondents. The variables associated with the OHIP-14 were: education, age, self-assessment, dental caries and the DMFT index. Conclusions: Self-perception of oral health was associated with OHIP-14 and the clinical indicators had low influence in the self-perception. Therefore, the development of educational initiatives and preventive strategies for the adult population is recommended. © BASCD 2011.

Caries experience associated to social and preventive factors in children of a pastoral community from Limeira-SP

Aim: To evaluate caries experience and prevalence associated to social and preventive factors in 3-6-year-old children of a Pastoral Community from Limeira, Brazil. Methods: A cross-sectional study was carried out through an epidemiologic research about the oral conditions of 110 children registered at the Children's Pastoral Community from the city of Limeira, SP, Brazil. Intraoral examination was performed by a trained dentist and the parents/caregivers filled out a questionnaire in order to outline the children's profile with respect to gender, parental education and oral health. Results: Differences related to gender were not detected (p= 0.3404). The most frequent periods of breastfeeding were 0 to 2 months (36.36%) and 2 to 6 months (35.45%), corresponding to 71.81% of the cases. The time bottle feeding pointed to two most frequent categories: 1) more than 12 months (35.45%) and 2) between 2 and 6 months (22.63%). Regarding parental education, the majority of the sample has not completed primary school (38.32%). It was observed a larger number of decayed teeth in male children (63.39%). Caries experience was significantly higher in children who were breastfed for only 2 months of life (41.96%). Children that did not use baby bottle or did not use a baby bottle for more than 1 year presented a smaller dmft, corresponding to 29.17% and 28.33%, respectively. Time of use of bottle and pacifier presented a significant association (p<0.05). Conclusions: The implementation of adequate strategies and actions is needed to reinforce oral health conditions in risk groups.

Dentistry for babies: Caries experience vs. Assiduity in clinical care

Aim: This study analyzed and compared the experience of dental caries in 300 children aged 0 to 48 months, who were participants and non-participants of a preventive program 'Dentistry for babies', as well as the correlation between assiduity of dental visits and experience of dental caries. Methods: The subjects were randomly selected and divided into two groups: G1 'Non participant children of the Program' (n=100) and G2 'Participant Children of the Program' (n=200). Each group was subdivided in two subgroups: 0-24 months and 25-48 months. The collected data from G2 were analyzed, relating the variation of the dmft index (dmft refers to primary teeth: d = decayed, m = missing/extracted due to caries, f = filled, t = teeth) (C) and dental caries prevalence (P) with the influence of assiduity factor in each subgroup. To collect data, clinical examinations were performed using tactile and visual criteria by a single calibrated examiner. The data were statistically analyzed using the 'paired t-test', 'Mann-Whitney' and 'Chi-Squared' tests (p<0.05). Results: It was found that prevalence and dmft index were statistically significant (P=0.0001) with the greatest values observed in G1 (p=0.0001). The values were: PG1 (73%), PG2 (22%), CG1 (3.45±3.84), CG2 (0.66±1.57). Assiduity was significant in G2 (p=0.0001). The values observed were: P-Assiduous (2%), P-Non-assiduous (42%), C-Assiduous (0.04±0.31), and C-Non-assiduous (1.29±2.01). Conclusions: The participation in the program had a positive influence on the oral health of babies. Complete assiduity to the program resulted in the lowest rates and prevalence of dental caries.

Caring for heart transplant recipients: The lived experience of primary caregivers

Objective: To understand the experience of primary caregivers of heart transplant recipients. Methods: A phenomenological approach was used to understand the caregivers' experience of caring for a heart transplant patient. In-depth interviews were conducted with 11 caregivers, in a Brazilian hospital, from December 2008 to March 2009. Results: Following the transplant, caregivers' lives change drastically; their priority becomes providing care for their relative. Despite successful transplant results, the uncertainty about future remains, generating permanent distress. Anxiety is exacerbated by familial or economic problems and, consequently, many participants turn to their local communities for support. Some caregivers learn from the experience and plan return to regular activities. Others feel helpless, unable to overcome personal losses and difficulties. Conclusions: Nurses are ideally placed to lead the way by providing family-centered support and education for caregivers of heart recipients. Listening to the concerns of family caregivers seems to be an essential aspect of effective interventions. © 2013 Elsevier Inc.

Dental caries experience and Molar-Incisor Hypomineralization

Objective. This cross-sectional study assessed the prevalence and severity of the enamel defects, known as Molar-Incisor Hypomineralization (MIH) and its relationship to dental caries. Materials and methods. A sample of 1157 schoolchildren (population based), aged 6-12 years, of the Araraquara city-Brazil, was evaluated according to the European Academy of Paediatric Dentistry (EAPD) criteria by two trained examiners. The dental impact caused by MIH was evaluated with the Decayed, Missing and Filled Teeth (DMFT) index (WHO). Data were analyzed using ANOVA and Chi-square tests (p < 0.05). The socioeconomic status was collected using a questionnaire answered by parents. Results. The prevalence of MIH was 12.3%. Mild impairment was the most frequent diagnosis. DMFT of children with MIH was 0.89 (±1.18), which are higher than those of the unaffected group (0.43 ± 1.01). An association was found between dental caries only in the permanent dentition of children with MIH (p = 0.0001). Family income was considered low in 85% of the families of children with MIH in the public system, while in private school it was 18% (p < 0.05). Conclusion. The prevalence of MIH in Araraquara was associated with greater caries experience in the permanent dentition. © 2013 Informa Healthcare.

Comparison of the caries-preventive effect of a glass ionomer sealant and fluoride varnish on newly erupted first permanent molars of children with and without dental caries experience

Purpose: This longitudinal clinic study evaluated the effect of a glass ionomer sealant (GIS) and a fluoride varnish (FV) in the prevention of dental decay on newly erupted permanent molars of children with and without caries experience. Materials and methods: Eighty children, aged 6-8 years, with all four newly erupted first permanent molars, were divided into two groups. Group 1 consisted of 53 children without caries experience and group 2 consisted of 27 children with dental caries experience. Permanent molars of the right side were sealed with GIS and the fluoride varnish was applied on the other two permanent first molars. Evaluation of GIS retention and the effectiveness of both materials in the prevention of dental caries were performed after 6, 12 and 18 months. Results: After 18 months, of the 299 teeth, 271 (91%) showed no caries lesions and 28 presented caries lesions (9%). Teeth sealed with GIS had more carious lesions (15) than teeth with fluoride varnish (13). Most of the teeth (70%) that presented carious lesions were in group 2. Of the 138 sealed teeth, only one showed GIS to be totally present, 95 were partially present and 42 teeth were absent. Conclusion: The caries-preventive effect was very similar between both treatments. The presence of dental caries prevailed in the children with caries experience. © 2013 Informa Healthcare.

Digital soil mapping: evaluation of sampling systems for soil surveys and refinement of soil maps at lower cost using legacy data

In soil surveys, several sampling systems can be used to define the most representative sites for sample collection and description of soil profiles. In recent years, the conditioned Latin hypercube sampling system has gained prominence for soil surveys. In Brazil, most of the soil maps are at small scales and in paper format, which hinders their refinement. The objectives of this work include: (i) to compare two sampling systems by conditioned Latin hypercube to map soil classes and soil properties; (II) to retrieve information from a detailed scale soil map of a pilot watershed for its refinement, comparing two data mining tools, and validation of the new soil map; and (III) to create and validate a soil map of a much larger and similar area from the extrapolation of information extracted from the existing soil map. Two sampling systems were created by conditioned Latin hypercube and by the cost-constrained conditioned Latin hypercube. At each prospection place, soil classification and measurement of the A horizon thickness were performed. Maps were generated and validated for each sampling system, comparing the efficiency of these methods. The conditioned Latin hypercube captured greater variability of soils and properties than the cost-constrained conditioned Latin hypercube, despite the former provided greater difficulty in field work. The conditioned Latin hypercube can capture greater soil variability and the cost-constrained conditioned Latin hypercube presents great potential for use in soil surveys, especially in areas of difficult access. From an existing detailed scale soil map of a pilot watershed, topographical information for each soil class was extracted from a Digital Elevation Model and its derivatives, by two data mining tools. Maps were generated using each tool. The more accurate of these tools was used for extrapolation of soil information for a much larger and similar area and the generated map was validated. It was possible to retrieve the existing soil map information and apply it on a larger area containing similar soil forming factors, at much low financial cost. The KnowledgeMiner tool for data mining, and ArcSIE, used to create the soil map, presented better results and enabled the use of existing soil map to extract soil information and its application in similar larger areas at reduced costs, which is especially important in development countries with limited financial resources for such activities, such as Brazil.

Experience with the sandwich technique in endovascular thoracoabdominal aortic aneurysm repair

Background: The sandwich technique is an endovascular off-the-shelf solution for patients with thoracoabdominal aortic aneurysms (TAAAs). In a sandwich configuration, the chimney stent runs in the middle of a space created by two or three aortic endografts.Methods: All patients with TAAAs who were treated with the sandwich technique were included in the study. Self-expanding Viabahn grafts (W. L. Gore and Associates Inc, Flagstaff, Ariz) were used as parallel grafts in the renal arteries and visceral vessels. Caudad-facing chimney grafts were used for the visceral arteries and cephalad-facing periscope grafts for the renal arteries.Results: During the study period, 32 patients with TAAAs were treated with sandwich grafts. Indication for the procedure in 43% was an acute onset of symptoms, including two patients with a rupture and a retroperitoneal hematoma. Three patients required an additional debranching procedure. A total of 104 chimney grafts were implanted. Two patients died postoperatively because of the operation. Major adverse events were recorded in five patients, including one patient with persistent paraplegia and two with permanent renal failure requiring dialysis. The incidence of chimney graft occlusion was higher in patients with three or four parallel grafts than in those with two chimney grafts only. Patients with chronic dissections had a 12-times higher incidence of chimney graft occlusion than aneurysm patients. The number of patients with type I or III endoleaks was higher in the group with three or four parallel grafts.Conclusions: The sandwich technique is an off-the-shelf endovascular alternative to treat patients with TAAAs in an emergent setting. The combination of chimney grafts with a periscope configuration enables a rapid endovascular aneurysm exclusion with acceptable midterm results.

Computer intensive methods for controlling bias in a generalized species diversity index

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)