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

Experimental evidence for the influence of structure and meaning on linear order in the noun phrase

Recent work has used artificial language experiments to argue that hierarchical representations drive learners’ expectations about word order in complex noun phrases like these two green cars (Culbertson & Adger 2014; Martin, Ratitamkul, et al. 2019). When trained on a novel language in which individual modifiers come after the Noun, English speakers overwhelmingly assume that multiple nominal modifiers should be ordered such that Adjectives come closest to the Noun, then Numerals, then Demonstratives (i.e., N-Adj-Num-Dem or some subset thereof). This order transparently reflects a constituent structure in which Adjectives combine with Nouns to the exclusion of Numerals and Demonstratives, and Numerals combine with Noun+Adjective units to the exclusion of Demonstratives. This structure has also been claimed to derive frequency asymmetries in complex noun phrase order across languages (e.g., Cinque 2005). However, we show that features of the methodology used in these experiments potentially encourage participants to use a particular metalinguistic strategy that could yield this outcome without implicating constituency structure. Here, we use a more naturalistic artificial language learning task to investigate whether the preference for hierarchy-respecting orders is still found when participants do not use this strategy. We find that the preference still holds, and, moreover, as Culbertson & Adger (2014) speculate, that its strength reflects structural distance between modifiers. It is strongest when ordering Adjectives relative to Demonstratives, and weaker when ordering Numerals relative to Adjectives or Demonstratives relative to Numerals. Our results provide the strongest evidence yet for the psychological influence of hierarchical structure on word order preferences during learning

A Picture is Worth a Thousand Words: Consumer Perceptions of Agricultural Images

Individuals interpret agricultural images differently according to the direct or cultural meanings they associate with the image, as well as the perspective through which they view the image. In addition, perceptions of agricultural images are commonly influenced by stereotypes. As agricultural communicators, it is important to understand the perceptions consumers have about agricultural images. Understanding these perceptions can allow communicators to use images in their communication that will promote favorable perceptions of the industry. To better understand consumers’ perceptions of agricultural images, this study asked consumers about their perceptions using focus group methodology. Four focus groups were completed with a total of 36 participants. The results indicated that elements of semiotics and perception theory were evident in the participants’ discussion. Thus, these theories combined with the results provide valuable information in regard to selecting images for communication that will create favorable responses among consumers

Cross-linguistic evidence for cognitive universals in the noun phrase

Noun phrase word order varies cross-linguistically, however, two distributional asymmetries have attracted substantial attention (i.a., Greenberg 1963, Cinque 2005). First, the most common orders place adjectives closest to the noun, then numerals, then demonstratives (e.g., N-Adj- Num-Dem). Second, exceptions to this are restricted to post-nominal position (e.g., N-Dem- Num-Adj, but not Adj-Num-Dem-N). These observations have been argued to reflect constraints on cognition. Here we report two experiments, following work by Culbertson & Adger (2014), providing additional support for this claim. We taught English- and Thai-speaking participants artificial languages in which the position of modifiers relative to the noun differed from their native order (post-nominal position in English, pre-nominal in Thai). We trained participants on single-modifier phrases, and asked them to extrapolate to multiple modifier phrases. We found that both populations infer relative orders of modifiers that conform to the tendency for closest proximity of adjectives, then numerals, then demonstratives. Further, we show that Thai participants, learning pre-nominal modifiers, exhibit a stronger such preference. These results track the typology closely and are consistent with the claim that noun phrase word order reflects properties of human cognition. We discuss future research needed to rule out alternative explanations for our findings, including prior language experience

Pig production feeding and management of the brood sow and litter

Successful pork production depends first upon selection of good breeding stock. The breeding stock selected should have the inherent ability to produce and nurse a large litter that will use feed efficiently. Equally important are proper feeding and management of the brood sow and her litter. It is a good plan to separate the gilts from the fattening hogs at 4 to 5 months of age and feed them a growing ration. Whole oats or a mixture of one-half oats and barley or wheat coarsely ground, self-fed, constitute a good foundation for a ration. Enough corn should be fed, probably a couple of ears daily, to each gilt to keep her gaining. One-half gallon of skimmilk daily or 1/2 pound of protein concentrate will furnish sufficient protein for one gilt in addition to what she obtains from grain and pasture. (The protein concentrate may be hand-fed or mixed with the grain on the basis of 5 pounds to each 100 pounds of grain.

How Engineering Standards are Interpreted and Translated for Middle School

In this exploratory study we examined the alignment of Next Generation Science Standards (NGSS) middle school engineering design standards with lesson ideas from middle school teachers, science education faculty, and engineering faculty (4–6 members per group). Respondents were prompted to provide plain language interpretations of two middle school Engineering Design performance expectations and to provide examples of how the performance expectations could be applied in middle school classrooms. Participants indicated the challenges and benefits of implementing these performance expectations and indicated personal experiences that helped them to interpret the performance expectations. Quality of lessons differed depending on the performance expectation being addressed. Generally, respondents were better able to generate ideas that addressed the paradigm of students ‘‘analyz[ing] data from tests to determine similarities and differences among several design solutions’’ than having students ‘‘define the criteria and constraints of a design problem.’’ A notable finding was the scarcity of quality engineering lesson ideas. The greatest proportion of lessons were categorized as Vague and/or Overly Broad. It appears that NGSS engineering design standards can too easily be decoded in an excessively expansive manner, thus resulting in indefinite ideas that are difficult to translate into classroom practice