Detection of signals in presence of noise through Josephson junction switching currents.

Josephson junctions can be employed to reveal a sinusoidal signal in presence of Gaussian noise. To mimic realistic setups, the detection is performed linearly ramping the bias current until a switch to the finite voltage occurs; the analysis of the resulting switching currents can be exploited to decide about the presence of the harmonic drive. The signal is applied in two conditions: with an unknown initial phase (incoherent strategy) and with a known initial phase (coherent strategy). In both conditions, the analysis of the efficiency of the detection, performed through the signal-to-noise ratio, as estimated by the Kumar-Carrol index, shows that the dependence upon the Josephson junction ramp rate is beneficial, especially for relatively fast speed. One can conclude that the collection of the switching currents is a robust technique, and thus it is possible to exploit the advantages of a predetermined finite time to collect the data.

Antibacterial effect of coffee: calcium concentration in a culture containing teeth/biofilm exposed to Coffea Canephora aqueous extract.

UNLABELLED: This study determined the changes of calcium concentration in a medium containing teeth/biofilm exposed to Coffea canephora extract (CCE). Enamel fragments were randomly fixed into two 24-well polystyrene plates containing BHI. Pooled human saliva was added to form biofilm on fragments. Specimens were divided into treatment groups (G, n = 8 per group) and treated with 50 µl daily for 1 min per week, as follows: G1, 20% CCE; G2, Milli-Q water (negative control); G3, antibiotic (positive control). Six fragments represented the blank control (G4). The calcium content was observed at baseline, 4 and 7 days of treatment by atomic-absorption spectrophotometry. Cross-sectional hardness of enamel was a demineralization indicator. Calcium increased in the medium after 4 and 7 days of treatment in G1 (3·80 ± 1·3 mg l(-1) and 4·93 ± 2·1 mg l(-1) , respectively) and G3 (4th day = 5·7 ± 1·8 mg l(-1) ; 7th day = 6·7 ± 3·5 mg l(-1) ) (P > 0·05). Calcium from G2 decreased after 7 days, which was different from G3 (P < 0·05). The lower calcium content, at the end of the experiment, was represented by G4, 2·16 ± 0·2 mg l(-1) . The increase in calcium after treatment with CCE is probably due to its antibacterial effect, which caused the bacterial lysis and consequent release of calcium in the medium. SIGNIFICANCE AND IMPACT OF THE STUDY: This study revealed an inhibitory action of Coffea canephora against dental biofilm. This coffee species caused bacterial lysis and consequent release of calcium into the medium. Furthermore, the advantage of coffee as an antibacterial beverage is that it is consumed in a concentrated form (6-10%) as opposed to various medicinal infusions that have shown such effect in vitro and are usually consumed at 1-2%. Therefore, a light roasted C. canephora aqueous extract can be considered as a potential anticariogenic substance.

Cross-sectional microhardness of bovine enamel subjected to three paediatric liquid oral medicines: an in vitro study.

AIM: This study aimed to investigate the in vitro effects of three paediatric liquid oral medicines on bovine dental enamel subsurfaces under pH cycling conditions. METHODS: Bovine enamel blocks were evaluated for surface hardness at baseline for sample selection. 52 intact bovine enamel blocks (16mm(2)) were randomly divided into four groups (n=13) according to the immersion treatments: G1: antibiotic (Klaricid®), G2: antihistamine (Claritin®), G3: antihistamine (Dimetapp®) and G4: control (de-ionised water). The blocks were submitted to pH cycling treatments twice a day for 12 days. The medicines were evaluated for pH, viscosity, and concentration of calcium, phosphate and fluoride. After the treatment period, cross-sectional microhardness (CSMH) measurements of the enamel blocks were taken and the data, expressed in Knoop hardness number (kg/mm(2)) was used to calculate the ΔS. STATISTICS: ANOVA followed by the Tukey test were used for statistical analyses (p<0.05). RESULTS: The antibiotic Klaricid® showed the highest concentration of fluoride, calcium and phosphate. Considering pH and viscosity, the following pattern was observed according to the treatment group: G4>G1>G2>G3 and G1>G2>G3>G4 respectively. Regarding the demineralisation pattern, the following results were observed: G4>G3>G2>G1. Compared to the control, the antibiotic and both the antihistamines provoked less demineralisation of the enamel blocks (p<0.05). CONCLUSIONS: Antibiotic G1 (Klaricid®) presented an in vitro protective effect against acid attacks probably due to its mineral content and viscosity.

Inhibitory properties of Coffea canephora extract against oral bacteria and its effect on demineralisation of deciduous teeth.

OBJECTIVES: The antibacterial activity of Coffea canephora extract was evaluated in vitro against Streptococcus mutans and Streptococcus sobrinus. The viability of planktonic cells was analysed by susceptibility tests (MIC and MBC) and time-kill assays. The effect of the extract on dental demineralisation was also investigated. METHODS: Primary 1st molar fragments (n=24) were inoculated with a saliva pool and sustained in a multiple plaque growth system for 10 days to form biofilm. The biofilm was treated with light roasted C. canephora extract at 20%, Milli-Q water (negative control) and chlorhexidine (positive control) once a day, during a week. Blank controls comprised fragments without treatment. Biofilm pH was monitored in the last day of treatment. Changes in tooth mineralisation were assessed by cross-sectional microhardness (CSMH) test. RESULTS: MIC and MBC for S. mutans were 7±2 mg/mL and 160±0 mg/mL, respectively, showing no activity for S. sobrinus. The extract produced a 4-log reduction in the number of colonies of S. mutans after 3-h treatment (p<0.05) with undiluted extract (20%) and MBC concentration (16%). There was no difference among negative/blank controls and coffee plaque pH. Differences between CSMH values of dental fragments subjected to the coffee extract and to chlorhexidine were not significant. At depths up to 30 µm from the enamel surface, coffee extract and chlorhexidine promoted higher CSMH values when compared to blank/negative controls (p<0.05). CONCLUSION: Our data suggest that light roasted C. canephora extract is beneficial as an anticariogenic substance.

Reliability of two methods for measurement of alveolar bone level in children.

OBJECTIVES: To determine the intra- and interexaminer reliability of two methods (calliper and computerized images) for measuring the alveolar bone level on bitewing radiographs of pre-school children and to determine the extent to which one method can measure more sites. METHODS: Standardized paediatric bitewings were analysed with either an image analysis program (ImageTool) or a digital calliper (Digimatic Caliper). With each method, radiographs were measured three times by three trained examiners. The differences in the number of sites measured with the two methods were assessed with McNemar's tests and kappa statistics. Reliability was assessed with paired t-tests, intraclass correlation coefficients (ICCs), Bland-Altman and survival-agreement plots. RESULTS: The kappa statistics and McNemar's test indicated that examiners measured 14% fewer sites using ImageTool. Paired t-tests also demonstrated a statistically significant bias (range 0.11-0.23 mm) indicating larger measurements for this method, although these observed differences were considered clinically unimportant for the detection of 2 mm of bone loss (which was considered the threshold for periodontal disease). Intra- and interexaminer reliability (ICC range: 0.87-0.97) was considered good for both methods. CONCLUSIONS: Reliable methods to assess alveolar bone loss in primary teeth are important for the diagnosis of incipient periodontal diseases. Both studied methods proved to be reliable. With the Digimatic Caliper, however, more sites were measured.

Band gap formation and multiple scattering in photonic quasicrystals with a Penrose-type lattice.

This Letter presents a study of the local density of states (LDOS) in photonic quasicrystals. We show that the LDOS of a Penrose-type quasicrystal exhibits small additional band gaps. Among the band gaps, some exhibit a behavior similar to that typical of photonic crystals, while others do not. The development of certain band gaps requires large-size quasicrystals. It is explained by the long-range interactions involved in their formation. Moreover, the frequencies where the band gaps occur are not necessarily explained using single scattering and should therefore involve multiple scattering.

Rejection properties of stochastic-resonance-based detectors of weak harmonic signals.

In [Phys. Rev. E 57, 6470 (1998)]] a thorough characterization in terms of receiver operating characteristics of stochastic-resonance detectors of weak harmonic signals of known frequency in additive Gaussian noise was given. It was shown that strobed sign-counting based strategies can be used to achieve a nice trade-off between performance and cost, by comparison with noncoherent correlators. Here we discuss the more realistic case where besides the sought signal (whose frequency is assumed known) further unwanted spectrally nearby signals with comparable amplitude are present. Rejection properties are discussed in terms of suitably defined false-alarm and false-dismissal probabilities for various values of interfering signal(s) strength and spectral separation.

Case report: the importance of oral manifestations in diagnosing iron deficiency in childhood.

AIM: The aim of this article is to report a case of iron deficiency diagnosed in a child after routine oral examination. CASE REPORT: A 5-year-old male child of African descent was brought to the paediatric dental clinic of a public university in Rio de Janeiro, Brazil. His mother's main complaint was her child's decayed teeth and sensitivity in the tongue every time he ate spicy or hot food. Anamnesis revealed chronic respiratory problems due to allergy, two previous episodes of anaemia and hospitalization about 15 months before the dental visit because of severe primary herpetic gingivostomatitis. Soft tissue examination revealed his tongue had various patches of atrophic mucosa characterizing absence of papillae in these areas. The child's dietary assessment indicated that he never ate meat or vegetables. Haematological investigation showed that the child probably had an iron deficiency, although the full blood count was not totally compatible with anaemia. A rapid initial recovery was quite noticeable after the beginning of oral therapy with ferrous sulphate, as remission of tongue sensitivity as well as papillae neoformation were observed.

[New experimental evidence of complex dynamics of heart beat. II. Correlation dimension, Lyapunov's exponents]. / Nuove evidenze sperimentali per la dinamica complessa del battito cardiaco. II: Dimensione di correlazione, esponenti di Lyapounov.

In this paper we applied mathematical techniques of non-linear dynamics, to an ECG signal. The first step is to compute the shift-delay time, via average displacement of the digital ECG. Phase space is constructed at a prescribed shift-delay and correlation dimension and dominant Lyapounov exponent versus the embedding dimension are monitored. This technique was applied to 5 healthy volunteers and 4 patients with VVI pacemaker.

[Otomastoiditis caused by Mycobacterium avium: a case report]. / Otomastoidite da Mycobacterium avium: descrizione di un caso.

Non tuberculous Mycobacterial (NTM) Infections mainly affect immunocompromised patients, appearing as disseminated or pulmonary disease. In immunocompetent children the most common form of infection with NTM is cervical adenitis. Ear infection seems to be a rare disease. We present a case of otomastoiditis caused by Mycobacterium avium in a 15 months old child, immunologically normal. Patient was referred for persistent right otitis unresponsive to routine medical therapy. TC scan of the ear and temporal bones revealed: soft tissue in external auditory canal, Eustachian canal, and middle ear overlying ossicles with erosion of tegmen tympani. Tuberculin skin test was positive with 5 units PPD and culture yielded M. avium. The patient undergo timpanomastoidectomy and medical therapy with antituberculous drugs and Steroids, subsequently he was given Clarithromycin and Rifabutin. M. avium is an ubiquitous low grade pathogen found in soil, water, dust and food. There is no evidence of direct transmission. Only a few cases of otomastoiditis due to M. avium have previously been reported. The case presented underlines the importance of microbiological investigations. When a NTM infection is suspected surgeons and infectious diseases specialists should cooperate to find an optimal treatment regimen of this unusual disease.

Unusual ultrastructural findings in giant-cell fibroblastoma.

We report on a 4-year-old boy with recurrent giant-cell fibroblastoma of the right nasal genal region. Histologic examination revealed that both lesions were constituted of spindle and stellate cells and a minor amount of multinucleated giant cells in a myxoid stroma containing cisternal-like spaces. Immunohistochemical examination revealed positivity for vimentin in both cellular components. Ultrastructural examination showed, in some spindle and multinucleated cells, two kinds of intracellular crystalline inclusions, located, respectively, in the cisternae of the rough endoplasmic reticulum and, apparently free, in the cytoplasm. To the best of our knowledge, this case, unusual for its location, is the first example of giant-cell fibroblastoma bearing intracellular crystalline inclusions.

[A rare case of endotympanic hemangioma]. / Su di un raro caso di emangioma endotimpanico.

Hemangiomas affectioning the external ear canal or the tympanic membrane have rarely been described. Only a very few cases are reported in world literature conarn these vascular tumors involving the middle ear space. The Authors report a rare case of a right endotympanic hemangioma associated with ossicular dysmorphism, resulting in conductive unilateral hearing loss, in a 9 year-old girl with cutaneous hemangiomas of the face. The Authors review Literature and discuss the possible pathogenetic implications of the intraoperatory findings.

Paranasal giant cell fibroblastoma: case report and immunohistochemical findings.

Few published reports describe patients with giant cell fibroblastoma, a rare, benign soft-tissue tumor that recurs locally and predominantly arises in children. A 4-year-old boy underwent surgery for removal of a giant cell fibroblastoma in the paranasal region, an unusual site. Six months after excision the tumor recurred locally. Immunohistochemical examination of the primary tumor and recurrence revealed vimentin positive staining in the cytoplasm of all the cells. The multinucleated giant cells and the flat cells bordering the vessel-like spaces were negative for Factor VIII-related antigen, S-100 protein, actin and desmin. Some histiocytes stained positively for alpha-1-antitrypsin, alpha-1-antichymotrypsin, antimacrophage and lysozyme antibodies. These immunoreactions indicate that giant cell fibroblastomas have a fibrohistiocytic origin.

Acinic cell carcinoma of the parotid gland in childhood.

A 13-year-old girl underwent surgery at the Ear Nose and Throat Department of the Children's Hospital and Scientific Research Institute, Bambino Gesù, Rome, because of an acinic cell carcinoma of the parotid gland. Two years after total parotidectomy with preservation of the facial nerve, metastasis occurred in a lateral cervical lymph node. Acinic cell tumors are uncommon in childhood; in children under the age of 16 years only 35 cases have been reported. There are too few acinar cell carcinomas occurring in children to yield an idea of their natural course. The neoplasm is also referred to as 'acinar cell tumor', in contrast to acinar cell carcinoma, because the neoplasm may be benign or malignant. Unfortunately, there are no histological distinguishing features that permit the pathologist to determine which neoplasm will behave in an aggressive fashion.

[Bronchoalveolar lavage (BAL) in the diagnosis of pulmonary infections in immunocompromised children]. / Il lavaggio bronco-alveolare (BAL) nella diagnostica delle infezioni polmonari nei bambini immunocompromessi.

The authors report their personal case records of broncho-alveolar lavage in immuno-compromised children. 22 children were observed from 1991 to 1992 at the E.N.T. Department of the Bambino Gesù Hospital, National Research Institute, in Rome. Flexible bronchoscopy is used under both local and general anesthesia without muscle relaxants. The epithelial lining fluid collection is greater than that obtained when muscle relaxation is used. For each patient 3 specimens are collected: for virological, bacteriological, mycological and immunological analysis. In 90% of the cases a correct etiological diagnosis of the pulmonary disease was possible. In 14 cases the diagnosis was possible even after a week from the beginning of the antibiotic therapy.

[Monostotic fibrous dysplasia of the temporal bone: description of a case and review of the literature]. / Displasia fibrosa monostotica del temporale: descrizione di un caso e revisione della letteratura.

Only a few cases of fibrous dysplasia of the temporal bone (monostotic form) have been described in the literature. The recent observation of a 15-year-old child presenting this pathology led the authors to review the literature available and to analyze the most common aspects of this disease. The clinical and radiological aspects, the differential diagnosis, histopathological features and therapeutical approaches are discussed.

Cervical chordoma in childhood: clinical statistical contribution.

Parapharyngeal neoplasias are rarely noticed in childhood, since they have their peak incidence between the 2nd and 4th decade of life. The authors report a case of a 4-year-old patient presenting with a retrostyloid mass, accompanied by nasal obstruction and some difficulty in swallowing at 12 months of age. CT scanning well ascertained the delimitation of the tumor, but it was of no help in the differential diagnosis. In fact, after surgical excision, the histological examination of the specimen revealed a chordoma. This result was unexpected because of the region concerned and the lack of a CT demonstration of the cervical boney involvement. A cervical vertebral localization of a chordoma is rare in all age groups and it is of particular clinical and statistical interest in infancy.

Otologic impairments in achondroplasia: a nosologic assessment.

The AA report a clinical and radiological study performed in 18 achondroplastic patients in order to achieve a nosological settlement of the otological impairments. They found two main otological syndromes; one, a congenital dysplasic syndrome, showing permanent conductive or sensory-neural hearing loss due to malformations of the middle ear or of the inner ear; the other, an inflammatory tubal tympanic syndrome with transient conductive hearing loss, which is relatively frequent in achondroplastic patients, but seems not related to the main disease.

Dysontogenetic neoplasms of the thyroid gland in infancy: two case reports.

Two rare cases of benign dysontogenetic neoplasms of the thyroid gland in pediatric age are presented, which were observed at the E.N.T. department of the Bambino Gesù Hospital of Rome, and successfully operated. The first case turned out to be a dysembryoma, classified as monodermic because of its origin from derivatives of only one germinal layer, the entoderm. The second case, a teratoma, presented a high seric concentration of AFP as the consequence of the synthetic activity of the share of embryonal epatic tissue present in the neoformation. Criteria to distinguish thyroid from cervical teratomata and to classify the different types of dysontogenetic neoplasms are discussed. The usual clinical and pathological manifestations of teratomas of the neck in infancy are mentioned. The necessity of a prompt surgical removal and of pre- and postoperative thyroid function studies is mentioned.