Current Filament Formation in Gold Compensated Silicon Pin Diodes

In semiconducting materials with current controlled negative differential conductivity an inhomogeneous current density distribution can arise leading to a well-defined spatial pattern in the form of current filaments. Detailed experiments are performed on silicon pin diodes showing a pronounced multistability in the current voltage characteristics. By using the voltage contrast and the electron beam induced voltage (EBIV) methods in a SEM, it is confirmed that each jump in the current is accompanied with the formation or disappearance of a well defined transverse electrical structure between the two contacts as a result of a current filament. This non-uniform state of the material is found to exhibit a clear solitary structure. The observed voltage oscillations are traced back to instabilities of this spatial structure

Confocal Laser Scanning Microscopy Investigation of the Penetration of Adhesives and Sealant Resins Into Fissures

Proces zalijevanja fisura u idealnim bi uvijetima trebao potpuno spriječiti prodor mokroarganizama u duboke jamice i fisure. Utvrđeno je da zaljevači sada dostupni na tržištu ne prodiru uvijek i potpuno u duboke i srednje duboke fisure tipa I (oblika pukotine) ili IK tipa (oblika ampula). S obzirom na nisku viskoznost i izvrsno vlaženje postojećih dentin adheziva, oni se upotrebljavaju u kombinaciji sa zaljevačima fisura da bi se poboljšala kvaliteta veze između zaljevača i cakline. Svrha ove ekspeimentalne studije bila je ispitati postoji li mogućnost poboljšanja penetracije zaljevača u fisure humanih molara, u kombinaciji s dentin adhezivima. Istraživanje je provedeno na 20 izvađenih intaktnih ljudskih molara i premolara. Čiščenje je učinjeno zračnim polirajućim uređajem 60 sekundi. Eksperimentalna grupa od 10 uzoraka tretirana je s dentin adhezivom Prime&Bond NT i zaljevačem fisura Dyrect Seal. Kontrolna skupina (10 zuba također) tretirana je samo sa zaljevačem fisura Dyrect seal. Tretirani uzorci rezani su na režnjeve debljine 700 mikrometara (ukupno 53 komada), usporedno sa zubnom osovinom. Vrjednovanje je provedeno s konfokalnim laserskim mikroskopom. Rezultati eksperimentalne skupine pokazuju da je 12 dubokih fisura potpuno punjeno, 9 nije bilo punjeno potpuno, 9 je bilo punjeno s postojanjem mjehurića zraka, a jedna široka fisura bila je punjena potpuno. Rezultati kontrolne skupine pokazuju da je 6 dubokih fisura potpuno punjeno, 19 nije punjeno, 5 je punjeno s postojanjem mjehurića zraka i 6 širokih fisura je punjeno potpuno. Uporabljen je Hi-kvadrat test za statističku raščlambu sa stupnjem korekcije p = 0,0465. To znači da postoji znatna razlika između kontrolne i eksperimentalne skupine. Uporaba dentin adheziva u metodi zalijevanja fisura ima određene prednosti u usporedbi s standardnom metodom zalijevanja fisura.The process of fissure sealing should ideally avoid the delivery of any microorganism subtrate into the depths of plaque-retentive pits and fissures. Up to now, available sealing materials have been found to not always completely penetrate to the bottom of deep and medium deep fissures of type I (slit-like) or type IK (ampoule-like). Due to the low viscosity and exellent wetting properties of current dentin adhesive systems, they were used in combination with sealant materials in order to improve the filling of fissures. The purpose of this experimental study was to evaluate whether penetration by filled sealing materialsinto fissures of human molars could be improved by combining them with enamel-dentin adhesives. The investigation was carried out on 20 extracted clinically caries-free, human premolars and molars. Cleaning was carried out with an air polishing device for 60 seconds. In the test groups, each containing ten teeth, a two material combination of an enamel-dentin adhesive (Prime&Bond NT) and a filled sealing resin was used to seal the fissures (Dyrect SEal). In the control groups (ten teeth) only the filled sealing material without an initial adhesive was applied. The scaled teeth were sectioned into slices of 700 micrometers in thickness (totla of 53 slices), parallel to the tooth axis. Evaluation under CLSM was carred out. In the experimental group, 12 deep fissures were completely filled, 9 were not filled, 9 were filled with bubbles of air, 1 wide fissure was filled. In the control group, 6 deep fissures were filled, 19 were not filled, 5 were filled with the bubbles of air and 6 wide fisures were filled. We used Chi-sqouare test as a statistic method and later Yatcs correction p = 0.0465. Differences between the control and experimental group are significant. Use of enamel-dentin-adhesive system in fissure sealing have some advantages

Exploring what works in art therapy with children with autism:Tacit knowledge of art therapists

Children with Autism Spectrum Disorders (ASD) are often referred to art therapy. To investigate what works in art therapy with these children 'tacit knowledge' of eight well experienced art therapists was explored. Promising components were arranged into the Context and Outcomes of Art Therapy (COAT) model. According to the respondents art therapy contributes with children with ASD to become more flexible and expressive, more relaxed, and more easy talking about their problems in the therapeutic setting as well as in their home situation. Considering the type of evidence in this study, further empirical research into the process and outcomes of art therapy with ASD children is strongly recommended

Community evaluation of glycoproteomics informatics solutions reveals high-performance search strategies for serum glycopeptide analysis

Glycoproteomics is a powerful yet analytically challenging research tool. Software packages aiding the interpretation of complex glycopeptide tandem mass spectra have appeared, but their relative performance remains untested. Conducted through the HUPO Human Glycoproteomics Initiative, this community study, comprising both developers and users of glycoproteomics software, evaluates solutions for system-wide glycopeptide analysis. The same mass spectrometrybased glycoproteomics datasets from human serum were shared with participants and the relative team performance for N- and O-glycopeptide data analysis was comprehensively established by orthogonal performance tests. Although the results were variable, several high-performance glycoproteomics informatics strategies were identified. Deep analysis of the data revealed key performance-associated search parameters and led to recommendations for improved 'high-coverage' and 'high-accuracy' glycoproteomics search solutions. This study concludes that diverse software packages for comprehensive glycopeptide data analysis exist, points to several high-performance search strategies and specifies key variables that will guide future software developments and assist informatics decision-making in glycoproteomics

Review of Matrix Metalloproteinases’ Effect on the Hybrid Dentin Bond Layer Stability and Chlorhexidine Clinical Use to Prevent Bond Failure

This review describes the relationship between dentin collagen hybrid bond layer degradation and the Matrix Metalloproteinases (MMPs) after their release by acid etch and rinse adhesives and self etching bonding adhesives that can reduce the bond stability over time. MMP-2, MMP-8 and MMP-9 are indicated as the active proteases that breakdown the collagen fibrils in the hybrid bond layer. Phosphoric acid in the acid etch and rinse bonding process and acid primers in the self etch process are implicated in the release of these proteases and their activation by several non-collagen proteins also released from dentin by the etching. MMPs are released in saliva by salivary glands, by cells in the gingival crevices to crevicular fluid and by pulpal odontoblasts cells to the dentinal fluids. These sources may affect the hybrid layer also. Evidence of the bond strength deterioration over time and the ability of Chlorhexidine to prevent bond deterioration by inhibiting MMP action are discussed. Dentin Bonding procedure utilizing Chlorhexidine for different application times and concentrations are being developed. The application of 2% Chlorhexidine to the phosphoric acid etch surface after rinsing off the acid is the only procedure that has been clinically tested for a longer period of time and shown to prevent bond strength degradation so far. The adoption of this procedure is recommended as means of improving bond stability at this time

Sensory Communication

Contains table of contents for Section 2, an introduction and reports on twelve research projects.National Institutes of Health Grant 5 R01 DC00117National Institutes of Health Contract 2 P01 DC00361National Institutes of Health Grant 5 R01 DC00126National Institutes of Health Grant R01-DC00270U.S. Air Force - Office of Scientific Research Contract AFOSR-90-0200National Institutes of Health Grant R29-DC00625U.S. Navy - Office of Naval Research Grant N00014-88-K-0604U.S. Navy - Office of Naval Research Grant N00014-91-J-1454U.S. Navy - Office of Naval Research Grant N00014-92-J-1814U.S. Navy - Naval Training Systems Center Contract N61339-93-M-1213U.S. Navy - Naval Training Systems Center Contract N61339-93-C-0055U.S. Navy - Naval Training Systems Center Contract N61339-93-C-0083U.S. Navy - Office of Naval Research Grant N00014-92-J-4005U.S. Navy - Office of Naval Research Grant N00014-93-1-119

Sensory Communication

Contains table of contents for Section 2, an introduction and reports on fifteen research projects.National Institutes of Health Grant RO1 DC00117National Institutes of Health Grant RO1 DC02032National Institutes of Health Contract P01-DC00361National Institutes of Health Contract N01-DC22402National Institutes of Health/National Institute on Deafness and Other Communication Disorders Grant 2 R01 DC00126National Institutes of Health Grant 2 R01 DC00270National Institutes of Health Contract N01 DC-5-2107National Institutes of Health Grant 2 R01 DC00100U.S. Navy - Office of Naval Research/Naval Air Warfare Center Contract N61339-94-C-0087U.S. Navy - Office of Naval Research/Naval Air Warfare Center Contract N61339-95-K-0014U.S. Navy - Office of Naval Research/Naval Air Warfare Center Grant N00014-93-1-1399U.S. Navy - Office of Naval Research/Naval Air Warfare Center Grant N00014-94-1-1079U.S. Navy - Office of Naval Research Subcontract 40167U.S. Navy - Office of Naval Research Grant N00014-92-J-1814National Institutes of Health Grant R01-NS33778U.S. Navy - Office of Naval Research Grant N00014-88-K-0604National Aeronautics and Space Administration Grant NCC 2-771U.S. Air Force - Office of Scientific Research Grant F49620-94-1-0236U.S. Air Force - Office of Scientific Research Agreement with Brandeis Universit