Human development and distance education: how are interactivity and interaction articulated?

Currently the achievements of technology have not been enough to overcome the misery, in which are numerous human groups. Relegated to its background, the human being sees those scenarios, which brings out discussions about its formation, in which values are regarded as the scientific and technological aspects. The educational research inspired by this framework involving the theme of human development, update and re-frame concepts related to the linkage between interactivity and interaction, two important features presented in the process of Distance Education (DE). The research inquired about how these features have been articulated. It conducted a field study in which two professors were interviewed. The results showed that the integration between interactivity and interaction, involving aspects such as autonomy, critical awareness, relationships among students, the sharing of values and worldviews, is at the base of the educational processes of the DE. They also showed that, on these processes, there are shortcomings regarding the development of values and having to be thought the tutor training strategies from an interdisciplinary view.

Bone healing pattern in surgically created circumferential defects around submerged implants: an experimental study in dog

Objective: To describe the healing of marginal defects below or above 1 mm of dimension around submerged implants in a dog model.Material and methods: In 12 Labrador dogs, all mandibular premolars and first molars were extracted bilaterally. After 3 months of healing, full-thickness flaps were elevated in the edentulous region of the right side of the mandible. Two recipient sites were prepared and the marginal 5mm were widened to such an extent to obtain, after implant installation, a marginal gap of 0.5mm at the mesial site (small defect) and of 1.25mm at the distal site (large defect). Titanium healing caps were affixed to the implants and the flaps were sutured allowing a fully submerged healing. The experimental procedures were subsequently performed in the left side of the mandible. The timing of the experiments and sacrifices were planned in such a way to obtain biopsies representing the healing after 5, 10, 20 and 30 days. Ground sections were prepared and histomorphometrically analyzed.Results: The filling of the defect with newly formed bone was incomplete after 1 month of healing in all specimens. Bone formation occurred from the base and the lateral walls of the defects. A larger volume of new bone was formed in the large compared with the small defects. Most of the new bone at the large defect was formed between the 10- and the 20-day period of healing. After 1 month of healing, the outline of the newly formed bone was, however, located at a similar distance from the implant surface (about 0.4mm) at both defect types. Only minor newly formed bone in contact with the implant, starting from the base of the defects, was seen at the large defects (about 0.8mm) while a larger amount was detected at the small defects (about 2.2 mm).Conclusion: Marginal defects around titanium implants appeared to regenerate in 20-30 days by means of a distance osteogenesis. The bone fill of the defects was, however, incomplete after 1 month.

Osteogenesis at implants without primary bone contact - An experimental study in dogs

Aim: To evaluate the healing at implants with a moderately rough surface placed and stabilized in recipient sites of dimensions deeper and larger than that of the implants to avoid any contact between parent bone and the implant.Material & methods: In six Labrador dogs, premolars and first molars were extracted bilaterally in the mandible. After 3 months of healing, mucoperiosteal full-thickness flaps were elevated and the premolar area of the alveolar bony crest was selected. Three recipient sites were prepared to place three implants. One implant was used as control. The other two were placed in recipient sites which left a circumferentially and periapical prepared defect of 0.7 mm (small) and 1.2 mm (large), respectively. All implants were stabilized with passive fixation plates to maintain the implants stable and without any contact with the implant bed. After 3 months of submerged healing, the animals were sacrificed. Ground sections were prepared and analyzed histomorphometrically.Results: The BIC% was 5.3% and 0.3% for implants placed in small and large defect sites, respectively, whereas it was 46.1% for control implants. The differences were statistically significant. The width of the residual defects was 0.4 and 0.5 mm at the small and large defects, respectively. An approximately 0.09 mm layer of dense connective tissue (DCT) rich in fibers and fibroblast-like cells was observed adherent to the implant surfaces. The percentage of implant surface covered by DCT was 92.8% and 95.6% at the small and large defects, respectively.Conclusion: Osseointegration was observed at the test sites, and the dimensions of the defects influenced the outcomes. However, the degree of osseointegration at both small and large defects was very low compared with the control sites.

Influence of implants with different sizes and configurations installed immediately into extraction sockets on peri-implant hard and soft tissues: an experimental study in dogs

Aim: To study the influence on the healing of soft and hard peri-implant tissues when implants of different sizes and configurations were installed into sockets immediately after tooth extraction.Material and methods: Transmucosal cylindrical implants, 3.3 mm in diameter in the control sites, and conical 5 mm in diameter in the test sites, were installed into the distal socket of the fourth mandibular premolars in dogs immediately after tooth extraction. After 4 months, the hard and soft tissue healing was evaluated histologically. Results: All implants were integrated in mineralized mature bone. Both at the test and control sites, the alveolar crest underwent resorption. The buccal bony surface at the implant test sites (conical; 3.8 mm) was more resorbed compared with the control sites (cylindrical; 1.6 mm). The soft tissue dimensions were similar in both groups. However, in relation to the implant shoulder, the peri-implant mucosa was located more apically at the test compared with the control sites.Conclusion: The present study confirmed that the distance between the implant surface and the outer contour of the buccal alveolar bony crest influenced the degree of resorption of the buccal bone plate. Consequently, in relation to the implant shoulder, the peri-implant mucosa will be established at a more apical level, if the distance between the implant surface and the outer contour of the alveolar crest is small.

A GEP-ISFG collaborative study on the optimization of an X-STR decaplex: data on 15 Iberian and Latin American populations

In a collaborative work carried out by the Spanish and Portuguese ISFG Working Group (GEP-ISFG), a polymerase chain reaction multiplex was optimized in order to type ten X-chromosome short tandem repeats (STRs) in a single reaction, including: DXS8378, DXS9902, DXS7132, DXS9898, DXS6809, DXS6789, DXS7133, GATA172D05, GATA31E08, and DXS7423. Using this X-decaplex, each 17 of the participating laboratories typed a population sample of approximately 200 unrelated individuals (100 males and 100 females). In this work, we report the allele frequencies for the ten X-STRs in 15 samples from Argentina (Buenos Aires, CA(3)rdoba, Rio Negro, Entre Rios, and Misiones), Brazil (SA o pound Paulo, Rio de Janeiro, Parana, and Mato Grosso do Sul), Colombia (Antioquia), Costa Rica, Portugal (Northern and Central regions), and Spain (Galicia and Cantabria). Gene diversities were calculated for the ten markers in each population and all values were above 56%. The average diversity per locus varied between 66%, for DXS7133, and 82%, for DXS6809. For this set of STRs, a high discrimination power was obtained in all populations, both in males (a parts per thousand yen1 in 5 A- 10(5)) and females (a parts per thousand yen1 in 3 A- 10(9)), as well as high mean exclusion chance in father/daughter duos (a parts per thousand yen99.953%) and in father/mother/daughter trios (a parts per thousand yen99.999%). Genetic distance analysis showed no significant differences between northern and central Portugal or between the two Spanish samples from Galicia and Cantabria. Inside Brazil, significant differences were found between Rio de Janeiro and the other three populations, as well as between SA o pound Paulo and Parana. For the five Argentinean samples, significant distances were only observed when comparing Misiones with Entre Rios and with Rio Negro, the only two samples that do not differ significantly from Costa Rica. Antioquia differed from all other samples, except the one from Rio Negro.

Long-Term Outcome and Prognostic Factors of Juvenile Dermatomyositis: A Multinational, Multicenter Study of 490 Patients

Objective. To investigate the long-term outcome and prognostic factors of juvenile dermatomyositis (DM) through a multinational, multicenter study.Methods. Patients consisted of inception cohorts seen between 1980 and 2004 in 27 centers in Europe and Latin America. Predictor variables were sex, continent, ethnicity, onset year, onset age, onset type, onset manifestations, course type, disease duration, and active disease duration. Outcomes were muscle strength/endurance, continued disease activity, cumulative damage, muscle damage, cutaneous damage, calcinosis, lipodystrophy, physical function, and health-related quality of life (HRQOL).Results. A total of 490 patients with a mean disease duration of 7.7 years were included. At the cross-sectional visit, 41.2-52.8% of patients, depending on the instrument used, had reduced muscle strength/endurance, but less than 10% had severe impairment. Persistently active disease was recorded in 41.2-60.5% of the patients, depending on the activity measure used. Sixty-nine percent of the patients had cumulative damage. The frequency of calcinosis and lipodystrophy was 23.6% and 9.7%, respectively. A total of 40.7% of the patients had decreased functional ability, but only 6.5% had major impairment. Only a small fraction had decreased HRQOL. A chronic course, either polycyclic or continuous, consistently predicted a poorer outcome. Mortality rate was 3.1%.Conclusion. This study confirms the marked improvement in functional outcome of juvenile DM when compared with earlier literature. However, many patients had continued disease activity and cumulative damage at followup. A chronic course was the strongest predictor of poor prognosis. These findings highlight the need for treatment strategies that enable a better control of disease activity over time and the reduction of nonreversible damage.

A Fast Large Scale Iris Database Classification with Optimum-Path Forest Technique: A Case Study

Majority of biometric researchers focus on the accuracy of matching using biometrics databases, including iris databases, while the scalability and speed issues have been neglected. In the applications such as identification in airports and borders, it is critical for the identification system to have low-time response. In this paper, a graph-based framework for pattern recognition, called Optimum-Path Forest (OPF), is utilized as a classifier in a pre-developed iris recognition system. The aim of this paper is to verify the effectiveness of OPF in the field of iris recognition, and its performance for various scale iris databases. This paper investigates several classifiers, which are widely used in iris recognition papers, and the response time along with accuracy. The existing Gauss-Laguerre Wavelet based iris coding scheme, which shows perfect discrimination with rotary Hamming distance classifier, is used for iris coding. The performance of classifiers is compared using small, medium, and large scale databases. Such comparison shows that OPF has faster response for large scale database, thus performing better than more accurate but slower Bayesian classifier.

Unicentric study of cell therapy in chronic obstructive pulmonary disease/pulmonary emphysema

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Electron microscopy study of lizard spermiogenesis in Tropidurus torquatus (Lacertilia)

In the course of an investigation on lizard spermiogenesis, the authors have observed events connected with the differentiation of the acrosome and middle-piece of the spermatozoa. Some differences from other reptilians were found as well as: the presence of a subacrosomal space, the absence of the fibrous sheath in the middle-piece, and a very short neck in the mature spermatozoa.

The effect of Ketoconazole on experimental paracoccidioidomycosis in the Syrian hamster: immunological and histopathological study

The effect of Ketoconazole (KTZ) on the hamster experimental intratesticular paracoccidioidomycosis was studied employing different treatment schedules. KTZ long course treatment beginning at an early stage of the infection was effective in preventing fungal proliferation, dissemination to lymph nodes, spleen and kidneys, and in maintaining low levels of humoral and cellular specific immune responses. KTZ short course treatment starting at an advanced stage of disease resulted in a more severe histopathological picture without significant changes in the immunological profile. The drug prolonged the life span of hamsters infected with Paracoccidioides brasiliensis, but did not prevent mortality. Toxic necrosis of the bone marrow occurred in normal animals receiving 120 mg/kg/day of KTZ but with lower doses no morphologic alterations were observed in heart, lungs, kidneys, adrenals, spleen, liver, intestine or bone marrow. © 1984 Dr W. Junk Publishers.

Effect of allopurinol in the course of adriamycin induced nephropathy

The role of superoxide in adriamycin-induced nephropathy (single dose; i.v. 3 mg/kg) has been studied by blocking superoxide synthesis through the administration of allopurinol (500 mg/L in drinking water). In Experiment I (EI), allopurinol administration was started 3 days prior to nephropathy induction and continued until day 14. In Experiment II (EII) allopurinol administration was started 2 weeks after nephropathy induction and was maintained until the end of the experiment (26 weeks). Affected glomeruli frequency and tubulointerstitial lesion index (TILI) were determined at Weeks 2 and 4 (EI) and Week 26 (EII). In EI, and 24 h mean proteinuria in the nephrotic control group (NCG-I) differed from that of the treated nephrotic group (TNG-I) at Week 1 (TNG = 33.3 ± 6.39 mg/24 h; NCG = 59.8 ± 6.3 mg/24 h; p < 0.05) and 2 (NCG-I = 80.0 ± 17.5 mg/24h; TNG-I = 49.1 ± 8.4 mg/24 h; p < 0.05). No glomerular alterations were observed and TILI medians were not different in both nephrotic groups at week 2 (NCG-I = 1+: TNG = 1+) and 4 (NCG = 4+; TNG = 4+). In EII, NCG-II and TNG-II presented different 24 h proteinuria values only at Week 6, (136.91 ± 22.23 mg/24 h ad 72.66 ± 10.72 mg/24 h, respectively; p < 0.05). Between nephrotic groups, there was no statistical difference in the median of affected glomeruli (CNG-II = 56%; TNG-II = 48% and TILI (NCG-II = 8+; TNG-II = 9+). Thus, allopurinol was associated with a transient reduction in proteinuria and it did not alter the progression of the nephropathy.

L-Histidine-europium(III) complex: A spectroscopical study

Chemical characterization as well as spectroscopical study of the L-histidine-europium(III) complex were developed both experimental and theoretically. Molecular mechanics (MM) simulation was performed in order to have indication of the compound structure and the Eu 3+ chemical environment. The Simple Overlap Model (SOM) was applied to predict spectroscopic quantities as 5D 0→ 7F 0/ 5D 0→ 7F 2 intensity ratio, 5D 0→ 7F 1 transition splitting and the intensity Ω λ parameters (λ = 2 and 4). Satisfactory results are obtained with 0.1 and 2/3 as the effective charges of the nitrogen (gN) and oxygen (gO) respectively, and their polarizabilities (α) depend on the distance. © 1999 Elsevier Science B.V. All rights reserved.

Influence of cholecalciferol (Vitamin D3) on the course of experimental systemic lupus erythematosus in F1 (NZBxW) mice

The course of systemic lupus erythematosus (SLE), an autoimmune disease, is markedly affected by hormones such as estrogen and prolactin. It is well known that heavy exposure to sunlight has deleterious effects on SLE, triggering episodes of the disease. Classical explanations for this occurrence suggest that UV radiation damages DNA, which becomes immunogenic, or induces exposure of the Ro antigen in keratinocytes. In recent years, it has been shown that vitamin D3 has important effects on the immune system. Thus, we proposed an alternative hypothesis, suggesting that UV radiation, by promoting vitamin D3 synthesis, could be a factor aggravating the course of SLE after exposure to sunlight. To test this hypothesis, we injected F1(NZBxW) mice, which are prone to developing SLE, with vitamin D3, and we demonstrated a worsening of the histopathological findings in the kidney. (C) 2000 Wiley-Liss, Inc.

The natural history of carpal tunnel syndrome: A study of 20 hands evaluated 4 to 9 years after initial diagnosis

Carpal tunnel syndrome (CTS) is the most frequent entrapment neuropathy. In the last decade several papers have been published on epidemiology, clinical aspects, diagnosis, and treatment, but little is known about its natural history. The objective of this work was to study the natural history of CTS syndrome. From 358 patients with clinical and conduction study diagnosis of CTS, 12 cases were identified that had refused surgical treatment, had not used anti-inflammatory medications, and had not undergone orthopaedic procedures, such as immobilization or anaesthetic infiltration. These 12 patients have 20 compromised hands which have been followed up for between 4 and 9 years. In all cases sensory and motor conduction studies were performed on the median nerve, at the beginning and end of follow-up period. Electrical improvement was marked in 5 hands and slight in 3; there was no significant change in 10, and deterioration in 2. As 8 hands (7 patients) showed improved clinical symptoms and conduction studies over several years, this brings the universally accepted procedure of surgical treatment into doubt.

Comparative study using small-angle x-ray scattering and nitrogen adsorption in the characterization of silica xerogels and aerogels

A comparative study using small-angle x-ray scattering (SAXS) and nitrogen adsorption has been carried out in the structural characterization of silica xerogels and aerogels, obtained from tetraethoxysilane sonohydrolysis. The specific surface and the mean pore size as measured by both the techniques were found to be in notable agreement in all cases for aerogels and xerogels. According to the SAXS data, aerogels at 500 °C exhibit a mass fractal structure with fractal dimension D∼2.4 in the range between the correlation length ξ∼5.3 nm and a∼0.75 nm. An experimental method to probe the mass fractal structure of aerogels from exclusively nitrogen adsorption isotherms has been presented. For aerogels at 500 °C, we have found D∼2.4 in the range between the pore width 2rξ∼33 nm and 2ra∼4.5 nm, which is in notable agreement with the SAXS results (D ∼2.4, ξ∼5.3 nm, a∼0.75 nm) if we assign the pore width 2r probed by the Kelvin equation in the adsorption method to the Bragg distance 2π/q associated to the correlation length 1/q probed by SAXS.