8 resultados para ISO 846-1978

em BORIS: Bern Open Repository and Information System - Berna - Suiça


Relevância:

20.00% 20.00%

Publicador:

Resumo:

The first part of this three-part review on the relevance of laboratory testing of composites and adhesives deals with approval requirements for composite materials. We compare the in vivo and in vitro literature data and discuss the relevance of in vitro analyses. The standardized ISO protocols are presented, with a focus on the evaluation of physical parameters. These tests all have a standardized protocol that describes the entire test set-up. The tests analyse flexural strength, depth of cure, susceptibility to ambient light, color stability, water sorption and solubility, and radiopacity. Some tests have a clinical correlation. A high flexural strength, for instance, decreases the risk of fractures of the marginal ridge in posterior restorations and incisal edge build-ups of restored anterior teeth. Other tests do not have a clinical correlation or the threshold values are too low, which results in an approval of materials that show inferior clinical properties (e.g., radiopacity). It is advantageous to know the test set-ups and the ideal threshold values to correctly interpret the material data. Overall, however, laboratory assessment alone cannot ensure the clinical success of a product.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Purpose: Gender-specific differences exist between male and female infertility patients' mental health, the meaning of infertility in their lives, and the coping strategies used. This systematic review examines whether gender-specific aspects are addressed in psychological intervention studies for infertility and whether infertile women and men benefit equally from such interventions. Methods: Databases were searched to identify relevant articles published between 1978 and 2007 (384 articles). The review included both controlled and uncontrolled psychological intervention studies examining results for infertile women and men separately. Outcome measures (depressive symptoms, anxiety, and mental distress) and gender-specific baseline characteristics (mental distress at pre-assessment, cause of infertility, and medical treatment) were collected. A total of twelve studies were finally included. Results: In 10 of 12 studies, women exhibited higher levels of mental distress than men. Gender-specific aspects were not addressed in the psychological interventions. Examining the efficacy of psychological interventions revealed that women exhibited stronger positive mental health effects in 2 of the 12 studies. Conclusion: Psychological distress before psychological treatment seems more pronounced in women than in men. Therefore psychological interventions for infertile couples should take gender-specific aspects into account. More research is needed to address the gender-specific aspects regarding psychological interventions for infertility.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

To evaluate if depth of cure D(ISO) determined by the ISO 4049 method is accurately reflected with bulk fill materials when compared to depth of cure D(new) determined by Vickers microhardness profiles.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

We present the synthesis of the two novel nucleosides iso-tc-T and bcen-T, belonging to the bicyclo-/tricyclo-DNA molecular platform. In both modifications the torsion around C6’–C7’ within the carbocyclic ring is planarized by either the presence of a C6’–C7’ double bond or a cyclopropane ring. Structural analysis of these two nucleosides by X-ray analysis reveals a clear preference of torsion angle γ for the gauche orientation with the furanose ring in a near perfect 2’-endo conformation. Both modifications were incorporated into oligodeoxynucleotides and their thermal melting behavior with DNA and RNA as complements was assessed. We found that the iso-tc-T modification was significantly more destabilizing in duplex formation compared to the bcen-T modification. In addition, duplexes with complementary RNA were less stable as compared to duplexes with DNA as complement. A structure/affinity analysis, including the already known bc-T and tc-T modifications, does not lead to a clear correlation of the orientation of torsion angle γ with DNA or RNA affinity. There is, however, some correlation between furanose conformation (N- or S-type) and affinity in the sense that a preference for a 3’-endo like conformation is associated with a preference for RNA as complement. As a general rule it appears that Tm data of single modifications with nucleosides of the bicyclo-/tricyclo-DNA platform within deoxyoligonucleotides are not predictive for the stability of fully modified oligonucleotides.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Welche politischen Voraussetzungen müssen gegeben sein, damit Regierungen den Staatshaushalt konsolidieren? In diesem Beitrag konzentrieren wir uns auf zwei Erklärungsgrößen: Die parteipolitische Zusammensetzung einer Regierung und die Breite der Regierungskoalition. Wir zeigen einerseits, dass die Wahrscheinlichkeit der Initiierung eines Konsolidierungsprogramms unter Parteien der politischen Rechten sowie unter kleinen Reformkoalitionen (Einparteienregierungen und minimal winning Koalitionen) am höchsten ist. Andererseits finden wir ein nahezu entgegengesetztes Muster bezüglich des Umfangs der verabschiedeten Sparmaßnahmen. Hier zeigt sich, dass die Breite der Regierungskoalition grundsätzlich einen positiven Einfluss auf die Größe des Konsolidierungsprogramms ausübt. Zudem fallen die Sparpakete rechter Parteien generell bescheidener aus als jene ihrer Konkurrenten der politischen Mitte und Linken. Wir erklären diese Ergebnisse mit den strategischen und wahlpolitischen Optionen der Akteure, auf Basis eines Vergleichs von 17 OECD-Ländern zwischen 1978 und 2009.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

We report 2 cases of Iso Kikuchi syndrome: A new born female patient with a 21 days history and a 62 year-old male. We present two cases of this unusual congenital abnormality of the nails at the extremes of life.