Differential Scanning Calorimetry (DSC) Analyses Of Superelastic And Nonsuperelastic Nickel-Titanium Orthodontic Wires

The purpose of this study was to determine the transformation temperatures for the austenitic, martensitic, and rhombohedral (R) structure phases in representative as-received commercial nitinol (NiTi) orthodontic wire alloys, to reconcile discrepancies among recent publications. Specimens were examined by differential scanning calorimetry (DSC) over a temperature range from approximately −170° C to 100° C, with a scanning rate of 10° C per minute. Two different pathways, with the intermediate R structure either absent or present, were observed for the transformation from martensitic to austenitic NiTi, whereas the reverse transformation from austenitic to martensitic NiTi always included the R structure. The enthalpy (ΔH) for the transformation from martensite to austenite ranged from 0.3 to 35 calories per gram. The lowest ΔH value for the nonsuperelastic Nitinol wire is consistent with a largely work-hardened, stable, martensitic microstructure in this product. The DSC results indicate that the transformation processes are broadly similar in superelastic, body-temperature shape-memory, and nonsuperelastic NiTi wires. Differences in bending properties for the NiTi orthodontic wires at room temperature and 37° C are due to the relative proportions of the metallurgical phases in the microstructures

Identifying the Strongest or the Weakest Link: Effects on Subsequent Ratings

The current study investigated the effect of a negative designation performance rating purpose in contrast to a positive designation purpose or a deservedness purpose on a) the ability of raters to differentiate amongst ratees at a later time and b) raters\u27 tendencies to provide subsequently more severe or lenient ratings. Results from a laboratory study involving 102 participants indicated that positive designations tend to result in subsequently lenient ratings, while negative designations result in severe ratings. However, the nature of a rater’s previous decision had no discernable effect on the ability to differentiate levels of performance. Implications of these findings for the structuring of performance ratings procedures in contexts of short-term performance observation, such as assessment centers, are discussed. Keywords: Assessment centers; Performance rating; Assimilation effect; Rating lenienc

Hydrolysis Velocity of Ketimines - Steric Hindrance Effect

Additional work has been carried on to gain further information concerning the significance of ortho-substituted groups upon the rate of which diphenyl ketimine hydrochlorides hydrolyze to ketones. In this particular study the following isomeric ketimines have been prepared and their hydrolysis velocities determined: 2, 6-dimethyl-, 2, 5-dimethyl-, 2, 4-dimethyl-, and 3, 5-dimethyldiphenyl ketimines hydrochlorides. The first of these with the two ortho-substituted methyl groups is hydrolyzed appreciably only after prolonged boiling with water. The last with no ortho-substituent is hydrolyzed very rapidly at room temperature, so that its reaction velocity must be measured at 0°C. The second and third ketimine salts, each having one ortho-substituted methyl, are hydrolyzed at a moderate rate at 25°

A conceptual model for in-service education for community college and technical institute occupational instructors who have not participated in traditional teacher education programs

The primary purpose of this study was the development of an in-service education model that was appropriate for occupational instructors in the community college and technical institute who did not participate in traditional teacher education programs. Secondary purposes of this study were: (1) to identify the roles that the teacher and the leader either perform or are expected to perform and (2) to identify the similar roles performed by the teacher and the leader

Sow Reproductive Stayability and Lifetime Traits

Sow longevity can be improved by selection, but genetic evaluations are challenged for implementation due to the long time interval required to collect complete lifetime data and low reliability of early indicator traits. Present study evaluated genetic parameters for several sow reproductive, stayability and longevity traits. Heritabilities for sow reproductive and longevity traits were estimated from 0.03 to 0.09. Heritabilities of the binary stayability traits were estimated from 0.00 to 0.14. Common litter effect had largest impact in early recorded traits. The results show that fitting the binary stayability traits to normal variance function give the lowest heritability estimates and the binomial variance function with logit function resulted in the highest estimates

Arteriovenous fistulae complicating cardiac pacemaker lead extraction: Recognition, evaluation, and management

AbstractTransvenous pacemaker lead extraction has become a commonly performed procedure that is associated with a small but significant risk. We report two cases where lead extraction was complicated by arteriovenous fistulae between branches of the aortic arch and the left brachiocephalic vein. Presenting signs and symptoms included severe chest or back pain, persistent or copious bleeding from the venous puncture site, unexplained hypotension or anemia, superior vena cava syndrome, and signs of central venous hypertension or acute heart failure. One patient whose injury was not recognized immediately and who did not undergo repair died rapidly, whereas the other patient who was diagnosed quickly underwent successful repair. Immediate diagnosis with arteriography and rapid intervention with surgery or percutaneous techniques are indicated and may prevent mortality. (J Vasc Surg 2000;32:1225-8.

The Building Blocks of Interoperability. A Multisite Analysis of Patient Demographic Attributes Available for Matching.

BackgroundPatient matching is a key barrier to achieving interoperability. Patient demographic elements must be consistently collected over time and region to be valuable elements for patient matching.ObjectivesWe sought to determine what patient demographic attributes are collected at multiple institutions in the United States and see how their availability changes over time and across clinical sites.MethodsWe compiled a list of 36 demographic elements that stakeholders previously identified as essential patient demographic attributes that should be collected for the purpose of linking patient records. We studied a convenience sample of 9 health care systems from geographically distinct sites around the country. We identified changes in the availability of individual patient demographic attributes over time and across clinical sites.ResultsSeveral attributes were consistently available over the study period (2005-2014) including last name (99.96%), first name (99.95%), date of birth (98.82%), gender/sex (99.73%), postal code (94.71%), and full street address (94.65%). Other attributes changed significantly from 2005-2014: Social security number (SSN) availability declined from 83.3% to 50.44% (p<0.0001). Email address availability increased from 8.94% up to 54% availability (p<0.0001). Work phone number increased from 20.61% to 52.33% (p<0.0001).ConclusionsOverall, first name, last name, date of birth, gender/sex and address were widely collected across institutional sites and over time. Availability of emerging attributes such as email and phone numbers are increasing while SSN use is declining. Understanding the relative availability of patient attributes can inform strategies for optimal matching in healthcare

Dependencies in language: On the causal ontology of linguistic systems

Dependency is a fundamental concept in the analysis of linguistic systems. The many if-then statements offered in typology and grammar-writing imply a causally real notion of dependency that is central to the claim being made—usually with reference to widely varying timescales and types of processes. But despite the importance of the concept of dependency in our work, its nature is seldom defined or made explicit. This book brings together experts on language, representing descriptive linguistics, language typology, functional/cognitive linguistics, cognitive science, research on gesture and other semiotic systems, developmental psychology, psycholinguistics, and linguistic anthropology to address the following question: What kinds of dependencies exist among language-related systems, and how do we define and explain them in natural, causal terms

Dependencies in language: On the causal ontology of linguistic systems

Dependency is a fundamental concept in the analysis of linguistic systems. The many if-then statements offered in typology and grammar-writing imply a causally real notion of dependency that is central to the claim being made—usually with reference to widely varying timescales and types of processes. But despite the importance of the concept of dependency in our work, its nature is seldom defined or made explicit. This book brings together experts on language, representing descriptive linguistics, language typology, functional/cognitive linguistics, cognitive science, research on gesture and other semiotic systems, developmental psychology, psycholinguistics, and linguistic anthropology to address the following question: What kinds of dependencies exist among language-related systems, and how do we define and explain them in natural, causal terms