FUR: Understanding functional reasoning

By functional reasoning we mean the ability of integrating shape, function, and plans in reasoning. the shape of many man-made objects, such as tools, is expressly designed to provide precise functionalities. Moreover, humans know how to use the same objects for different functions. In vision and reasoning we make use of complex information which is not exclusively based on geometric and spatial knowledge, but also on functional elements. They seem to play a role in object recognition and representation. This article is an insight in functional reasoning from the computational point of view. It introduces its concepts and its apparent ubiquity in human behavior. Some relevant computational literature is reported and discussed. the rest of the article is an outline of the FUR project, an attempt to develop a computational model for functional reasoning. the development state of the project is presented along with the implementation of a first prototype. Some experimental results are finally given.     

In vitro permeability evaluation and colonization of membranes for periodontal regeneration by Porphyromonas gingivalis

The use of membranes for periodontal regeneration is well established. In clinical use, the exposure of membranes to the oral microflora may result in a pathway for periodontal infections. An important role in this process is played by Porphyromonas gingivalis. The purpose of the present study was to examine the colonization of 6 different bioresorbable and nonresorbable membranes for periodontal regeneration by the strain DSM 20709 of P. gingivalis and to determine the time needed by this microorganism to pass through the membranes. A device consisting of a tube sealed with the membranes and filled with a medium suitable for the growth of P. gingivalis was incubated in a bigger tube containing the same medium to study the process of colonization and the crossing of membranes. The outer tube was inoculated with 10(4) cells of P. gingivalis DSM 20709. The passage of bacteria through the membranes was monitored at 6, 24, and 48 hours by counting the number of cells in the inner tube. The colonized membranes were observed using a scanning electron microscope. Differences in the behavior of the 6 membranes analyzed were demonstrated.     

A neural controller for the determination of the frequencydifference between laser sources

A new method for high-speed determination of the frequency separation between two laser sources is presented. The system is based on an artificial neural-network controller implementing a radial basis function network. The controller processes the signal produced by a scanning Fabry-Perot resonator in order to evaluate the frequency separation with good accuracy and bandwidth. The flexibility and the low cost make this approach suitable for application in spectroscopy and related fields. The system can be applied without substantial modifications to any tunable laser source     

Epilepsy provoked by television and video games: safety of 100-Hz screens

Television (TV) and video games (VG) can provoke seizures in patients with photosensitive epilepsies. Flicker frequency is the most important factor in screen activation. We tested conventional 50-Hz versus 100-Hz monitors during TV viewing and VG playing in 30 photosensitive subjects, 23 of whom had a history of TV or VG seizures or both. Fifteen subjects' discharges were activated by 50-Hz TV; 17 by 50-Hz VG; and one by a 100-Hz screen. Thus, 100-Hz screens protect against screen activation.     

Activated eosinophils in esophagitis in children: a transmission electron microscopic study

OBJECTIVE: To describe the interval between first appearance of mild nonproliferative diabetic retinopathy (NPDR) and first appearance of neovascularization (NV) in type I diabetes. SETTING: A longitudinal study of 269 patients followed up annually. PARTICIPANTS: Participants had insulin-dependent diabetes and were free of proliferative diabetic retinopathy in both eyes at the baseline visit. MAIN OUTCOME MEASURE: Stereoscopic color fundus photographs of each eye at each study visit, graded for features of retinopathy. RESULTS: Among the 305 eyes for which the duration of diabetes at the first appearance of mild NPDR could be determined, NV developed in 28 by the end of the study. Survival analysis showed that the later the onset of mild NPDR was, the shorter the time from onset of mild NPDR to onset of NV (relative hazard for each additional year to onset of mild NPDR, 1.22; 95% confidence interval, 1.10-1.35). Adjustment for systolic and diastolic blood pressure, proteinuria, and glycosylated hemoglobin (Hgb A10) levels did not change the relative hazard estimate for onset of mild NPDR. Higher levels of Hgb A10 were associated with a shorter time from onset of mild NPDR to onset of NV (relative hazard, 1.26; 95% confidence interval, 1.05-1.51 [after adjusting for time at onset of mild NPDR]), as were higher levels of diastolic blood pressure, although not significantly (relative hazard for 10-mm Hg increase in diastolic blood pressure, 1.52; 95% confidence interval, 0.82-2.83 [adjusting for onset of mild NPDR, Hgb A10 level, systolic blood pressure, and proteinuria]). Neither proteinuria nor systolic blood pressure had an effect on time from onset of mild NPDR to onset of NV, after adjustment for time at onset of mild NPDR, Hgb A10 level, and diastolic blood pressure. CONCLUSION: Later onset of mild NPDR is not necessarily associated with delayed development of NV in patients with type I diabetes. Caution must therefore be used in assessing the value of interventions that delay the onset of mild NPDR without evidence of delayed onset of NV.     

Maternal-fetal transmission of human papillomavirus

AIM: Human papilloma virus (HPV) infection is one of the most frequently observed sexually-transmitted diseases (10-60% of the general population). In pregnant women, as well as accelerating the evolution of dysplasia to cervical cancer, the infection may be transmitted to the fetus during gestation or at the time of birth. Children who have been infected at birth may develop laryngeal papillomatosis during the first 5 years of life that may, in some cases, spread to the point of causing aphonia or severe respiratory obstruction. There is also the risk, although it is very low, of a carcinomatous degeneration of the larynx in these subjects during adulthood. The hypothesis of the present study was to verify the prevalence of HPV infection in a population of pregnant women and the prevalence of maternal-fetal transmission. EXPERIMENTAL DESIGN: A prospective longitudinal design lasting 11 months was used for the study. It included the collection of an endocervical biopsy from population of pregnant women using a swab that was diluted in 3 cc of physiological solution, and the collection of oropharyngeal secretions from their respective neonates using a cottonwool bud. PARTICIPANTS AND METHODS: A total of 170 pregnant women attending the Obstetric Centre of the Obstetric and Gynecological Clinic of Trieste University were recruited in the study. An endocervical biopsy was taken during the 1st and/or 2nd trimester of gestation and/or at the start of labour. Of these subjects, 23 completed all the planned biopsies and a sample of oropharyngeal secretion was collected from their neonates. TESTS: From the material obtained the presence of HPV-DNA was analysed using a PCR (protein chain reaction) technique consisting of the following steps: 1) culture of human cells expressing sequences of HPV 16 and 18 used as positive controls; 2) preservation of tissue material washed in watery 4% formalin solution; 3) amplification and viral characterization in types 6-11-16-18-31-33-52. RESULTS: Positive HPV-DNA results in at least one of the three samples collected during the various periods of gestation was 31.2%, whilst in the population in which all the planned samples were performed the frequency of positive cases was 30.4%. Positive results for HPV-DNA in oropharyngeal secretions from neonates was 21.7%. The concordance of positivity for HPV-DNA in mothers at the time of labour and in their respective neonates was 57.14%. CONCLUSIONS: The trend of infection did not reveal substantial changes during the various gestational periods in which tests were performed. The possibility of HPV-DNA transmission from mother to fetus is high, above all when the maternal PCR test is positive at the time of birth, or in the presence of a high viral load. This justifies the need to monitor this infection in pregnancy in those affected by florid genital condylomatosis or with koilocytosis on cervical cytology. It is also appropriate to check all HPV-DNA positive neonates one year after birth.     

Optimization of the interaction between ethylenevinyl alcohol copolymers and human endothelial cells

To better understand and optimize the fine interactions that occur during adhesion events between human cells and synthetic materials, we seeded human umbilical vein endothelial cells (HUVEC) onto ethylene-vinyl alcohol (EVOH) copolymer films prepared by casting. Different adhesive proteins, e.g. fibronectin and gelatin, and the monoclonal antibody (MoAb) CLB-HEC19 specific for the endothelial cell membrane were used to coat the materials. We used atomic force microscopy (AFM) to analyse the EVOH film structure, to test its planarity and homogeneity, before seeding it with endothelial cells. The metabolic changes induced in the endothelial cells by interactions with the copolymer functional groups and the adhesive proteins were monitored by a micro-electronic pH sensor, positioned close to the HUVEC monolayer. We found that the adhesion of HUVEC onto various substrates was finely modulated by the MoAb CLB-HEC19 and that the endothelial cell metabolic rate was enhanced when cultured onto a CLB-HEC19 coating. Surface roughness seems also to play a role in the interaction with HUVEC. The AFM measurement analysis demonstrated that L6 surface is rougher than R20. These surface characteristics could favour cell adhesion; in fact HUVEC adhesion results on R20 were significantly lower than on L6.