Bonding with Self-etching Primers – Pumice or Pre-etch? An \u3cem\u3ein vitro\u3c/em\u3e Study

The purpose of this study was to compare the shear bond strengths (SBSs) of orthodontic brackets bonded with self-etching primer (SEP) using different enamel surface preparations. A two-by-two factorial study design was used. Sixty human premolars were harvested, cleaned, and randomly assigned to four groups (n = 15 per group). Teeth were bathed in saliva for 48 hours to form a pellicle. Treatments were assigned as follows: group 1 was pumiced for 10 seconds and pre-etched for 5 seconds with 37 per cent phosphoric acid before bonding with SEP (Transbond Plus). Group 2 was pumiced for 10 seconds before bonding. Group 3 was pre-etched for 5 seconds before bonding. Group 4 had no mechanical or chemical preparation before bonding. All teeth were stored in distilled water for 24 hours at 37°C before debonding. The SBS values and adhesive remnant index (ARI) score were recorded. The SBS values (±1 SD) for groups 1–4 were 22.9 ± 6.6, 16.1 ± 7.3, 36.2 ± 8.2, and 13.1 ± 10.1 MPa, respectively. Two-way analysis of variance and subsequent contrasts showed statistically significant differences among treatment groups. ARI scores indicated the majority of adhesive remained on the bracket for all four groups. Pre-etching the bonding surface for 5 seconds with 37 per cent phosphoric acid, instead of pumicing, when using SEPs to bond orthodontic brackets, resulted in greater SBSs

Bonding with Self-etching Primers – Pumice or Pre-etch? An \u3cem\u3ein vitro\u3c/em\u3e Study

The purpose of this study was to compare the shear bond strengths (SBSs) of orthodontic brackets bonded with self-etching primer (SEP) using different enamel surface preparations. A two-by-two factorial study design was used. Sixty human premolars were harvested, cleaned, and randomly assigned to four groups (n = 15 per group). Teeth were bathed in saliva for 48 hours to form a pellicle. Treatments were assigned as follows: group 1 was pumiced for 10 seconds and pre-etched for 5 seconds with 37 per cent phosphoric acid before bonding with SEP (Transbond Plus). Group 2 was pumiced for 10 seconds before bonding. Group 3 was pre-etched for 5 seconds before bonding. Group 4 had no mechanical or chemical preparation before bonding. All teeth were stored in distilled water for 24 hours at 37°C before debonding. The SBS values and adhesive remnant index (ARI) score were recorded. The SBS values (±1 SD) for groups 1–4 were 22.9 ± 6.6, 16.1 ± 7.3, 36.2 ± 8.2, and 13.1 ± 10.1 MPa, respectively. Two-way analysis of variance and subsequent contrasts showed statistically significant differences among treatment groups. ARI scores indicated the majority of adhesive remained on the bracket for all four groups. Pre-etching the bonding surface for 5 seconds with 37 per cent phosphoric acid, instead of pumicing, when using SEPs to bond orthodontic brackets, resulted in greater SBSs

Hydrolysis of Ks1- and L-casein-derived peptides with a broad specifcity aminopeptidase and proline specific aminopeptidases from Lactococcus lactis subsp. cremoris AM2

peer-reviewedAminopeptidase hydrolysis of αs1- and β-casein-derived synthetic peptides containing non-consecutive and consecutive proline residues was characterised. Aminopeptidase P (Pep P) (EC 3.4.11.9) or post-proline dipeptidyl aminopeptidase (PPDA) (EC 3.4.14.5) along with lysine-paranitroanilide hydrolase (KpNA-H) (EC 3.4.11.1) activities are required in the degradation of peptides containing non-consecutive proline residues. However, both Pep P and PPDA along with KpNA-H are required for hydrolysis of peptides containing consecutive proline residues. The results demonstrate the mechanism by which combinations of purified general and proline specific aminopeptidases from Lactococcus lactis subsp. cremoris AM2 hydrolyse peptides containing proline residues

Anthropogenic influence on the sedimentary regime of an urban estuary - Boston Harbor

Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Earth and Planetary Sciences, 1980.Microfiche copy available in Archives and Science.Vita.Bibliography: leaves 234-241.by Michael G. Fitzgerald.Ph.D

Purification and characterization of a lysine-p-nitroanilide hydrolase, a broad specificity aminopeptidase, from the cytoplasm of Lactococcus lactis subsp. cremoris AM2

peer-reviewedSummary. A hydrolase activity that cleaves lysyl-p-nitroanilide (Lys-pNA) has been purified from the cytoplasm of Lactococcus lactis subsp. cremoris AM2 by chromatography on DE52, DEAE Affi-Gel Blue Gel, Hydroxyapatite Bio-Gel HTP and Phenyl Sepharose. The purified aminopeptidase was found to have a native Mr of 50000-55000 by gel filtration chromatography and by FPLC gel filtration on Superose 12 and to be composed of a single polypeptide chain following SDS-PAGE. Enzyme activity was almost completely inhibited by EDTA, amastatin, puromycin and bestatin, while the sulphydryl-reactive agents p-chloromercuribenzoate and iodoacetamide were inhibitory. The enzyme was found to be very unstable during the puriification procedures at 4 °C and its stability was greatly improved when 10 ml glycerol/l and 2 mm-dithiothreitol were included in the puri®cation buffers. The puriified enzyme was found to hydrolyse a wide range of dipeptides, tripeptides and longer peptides provided that proline was not present in the penultimate position from the N-terminus or that a pyroglutamyl residue was not present at the N-terminus. While neither Asp-pNA nor Pro-pNA was hydrolysed by the purified enzyme, the release of N-terminal acidic residues from peptides was observed in addition to the release of N-terminal proline from Pro-Leu-Gly-NH2, Pro-Leu- Gly-Gly and Pro-His-Pro-Phe-His-Leu-Phe-Val-Tyr. This ability of Lys-pNA hydrolase to release N-terminal proline residues was employed in concert with a puriified aminopeptidase P preparation to release alternate N-terminal amino acids from Tyr-Pro-Phe-Pro-Gly. The complementary action of these enzymes represents an alternative mechanism to that of post-proline dipeptidyl aminopeptidase for metabolism of proline-containing peptides

Projecting Future Heat-Related Mortality under Climate Change Scenarios: A Systematic Review

Background: Heat-related mortality is a matter of great public health concern, especially in the light of climate change. Although many studies have found associations between high temperatures and mortality, more research is needed to project the future impacts of climate change on heat-related mortality

Air ambulance outcome measures using Institutes of Medicine and Donabedian quality frameworks: protocol for a systematic scoping review

Background: Dedicated air ambulance services provide a vital link for critically ill and injured patients to higherlevels of care. The recent developments of pre-hospital and retrieval medicine create an opportunity for airambulance providers and policy-makers to utilize a dashboard of quality performance measures to assess serviceperformance. The objective of this scoping systematic review will be to identify and evaluate the range of airambulance outcome measures reported in the literature and help to construct a quality dashboard based on ahealthcare quality framework. Methods: We will search PubMed, MEDLINE, CINAHL, Scopus, and Cochrane Database of Systematic Reviews (fromJanuary 2001 onwards). Complementary searches will be conducted in selected relevant journals. We will includesystematic reviews and observational studies (cohort, cross-sectional, interrupted time series) in critically ill orinjured patients published in English and focusing on air ambulance delivery and quality measures. Two reviewerswill independently screen all citations, full-text articles, and abstract data. The study methodological quality (or bias)will be appraised using appropriate tools. Analysis of the characteristics associated with outcome measure will bemapped and described according to the proposed healthcare quality framework. Discussion: This review will contribute to the development of an air ambulance quality dashboard designed tocombine multiple quality frameworks. Our findings will provide a basis for helping decision-making in healthplanning and policy

National standards for Higher Education programs in disaster management in Australia

Study/Objective: The aim of this project was to develop a framework for higher education programs in emergency and disaster management for Australia. Background: The development of such standards is of considerable value to Australia as it may contribute to national policy cohesion and also to capability development. The Generic Emergency and Disaster Management Standards define the scope and the domain in order to assist higher education institutions to develop programs that provide a relatively consistent and sound intellectual basis for the expertise required. Methods: The Generic Emergency and Disaster Management Standards were developed through a mixed qualitative research approach involving a systematic literature review, mapping of current course content, focus groups of experts and consultation with industry representatives. Results: The standards consist of three main domains. The knowledge domain included governance and policy frameworks, theoretical and conceptual basis for practice, and contemporary disaster management, skills and application. The skills domain included leadership, communication, and collaboration. Finally professional practice together with critical thinking is considered the means by which the knowledge and skills are applied. Conclusion: These standards are intended to provide a consistent and sound intellectual basis to assist higher education institutions to develop disaster and emergency management courses. While the focus is necessarily on the Australian context, it is recognized that University programs in Australia provide education to international students, and the methods used in developing these standards draw considerably from international sources, and thus they are likely to be of broader applicability. Additional mechanisms for the monitoring and ongoing development of these standards are required