Echo answers in native/non-native interaction

Normal fracture-healing involves a number of osteogenic factors that are released from bone and the surrounding soft tissues during the repair process. Osteogenic factors are involved in a number of processes related to bone formation and bone-remodeling, including chemotaxis, proliferation, and differentiation of bone-forming and bone-remodeling cells, blood vessels, nerves, and marrow elements. Local release of physiologic quantities of these osteogenic factors is generally sufficient to elicit fracture repair. Considerable effort has been expended in an attempt to accelerate fracture repair and to increase the assurance of healing by the exogenous application of these osteogenic factors. Similar efforts have been made to bridge critical-sized segmental defects and nonunions with the use of osteogenic factors. Determining the appropriate delivery vehicle for local application of these factors has been one of the major limitations to the success of these therapies. In addition, supraphysiologic doses of osteogenic factors appear to be required to achieve satisfactory results. Since the endogenous release of physiologic levels of osteogenic factors does not require a delivery vehicle for fracture repair, why is a delivery system required for exogenous delivery and why are the required doses so high? The answers to these questions may be related to the type of orthopaedic repair being attempted and the animal model being studied. The role of delivery vehicles for osteogenic factors is best understood in the context of bridging critical-sized defects. These defects by definition do not heal spontaneously. One of the primary roles of the delivery vehicle in this type of repair is to maximize the osteogenic effect of the delivered factors by maintaining these factors at the site of implantation and optimizing their release profile. Another important role of the delivery vehicle is to serve as an osteoconductive matrix for bone-forming cells while maintaining a space or volume in which …

Fracture of the long bones results in a repair process that has the potential to restore the anatomic morphology and mechanical integrity of the bone without scar tissue. The repair process can occur in two patterns. In the first, under conditions of rigid stabilization, direct osteonal remodeling of the fracture line can occur with little or no external callus, a process known as direct bone repair. The second pattern of repair involves bridging of the fragments with external callus and formation of bone in the fracture site by endochondral healing. This type of repair is known as indirect bone healing and occurs under less rigid interfragmentary stabilization. The rate of healing and the extent of callus in this type of repair can be modulated by the mechanical conditions at the fracture site. Applying cyclic interfragmentary micromotion for short periods has been shown to influence the repair process significantly, and characteristics of this stimulus influence the healing response observed. In the current study, a short term interfragmentary cyclic micromovement applied at a high strain rate induced a greater amount of periosteal callus than the same stimulus applied at a low strain rate. This high strain rate stimulus applied later in the healing period significantly inhibited the progress of healing. The beneficial effect of this particular biophysic stimulus early in the healing period may be related to the viscoelastic nature of the differentiating connective tissues in the early endochondral callus. In the early endochondral callus, high rates of movement induce a greater deformation of the fracture fragments because of the stiffening of the callus. Alternatively, the transduction pathway may involve streaming potentials as a result of the high movement rate.

Using on-line surveys to measure three key constructs of the quality of human–computer interaction in web sites: psychometric properties and implications

According to the International Classification of Functioning, Disability and Health (ICF), functioning reflects the interplay between an individual's body structures and functions, activities, participation, environmental, and personal factors. To be useful in clinical practice, these concepts need to be operationalized into a practical and integral instrument. The Brief ICF Core Set for Hearing Loss (CSHL) provides a minimum standard for the assessment of functioning in adults with hearing loss. The objective of the present study was to operationalize the Brief CSHL into a digital intake tool that could be used in the otology-audiology practice for adults with ear and hearing problems as part of their intake assessment. A three-step approach was followed: (1) Selecting and formulating questionnaire items and response formats, using the 27 categories of the Brief CSHL as a basis. Additional categories were selected based on relevant literature and clinical expertise. Items were selected from existing, commonly used disease-specific questionnaires, generic questionnaires, or the WHO's official descriptions of ICF categories. The response format was based on the existing item's response categories or on the ICF qualifiers. (2) Carrying out an expert survey and a pilot study (using the three-step test interview. Relevant stakeholders and patients were asked to comment on the relevance, comprehensiveness, and comprehensibility of the items. Results were discussed in the project group, and items were modified based on consensus. (3) Integration of the intake tool into a computer-based system for use in clinical routine. The Brief CSHL was operationalized into 62 items, clustered into six domains: (1) general information, including reason for visit, sociodemographic, and medical background; (2) general body functions; (3) ear and hearing structures and functions; (4) activities and participation (A&P); (5) environmental factors (EF); and (6) personal factors (mastery and coping). Based on stakeholders' responses, the instructions of the items on A&P and EF were adapted. The three-step test interview showed that the tool had sufficient content validity but that some items on EF were redundant. Overall, the stakeholders and patients indicated that the intake tool was relevant and had a logical and clear structure. The tool was integrated in an online portal. In the current study, an ICF-based e-intake tool was developed that aims to screen self-reported functioning problems in adults with an ear/hearing problem. The relevance, comprehensiveness, and comprehensibility of the originally proposed item list was supported, although the stakeholder and patient feedback resulted into some changes of the tool on item-level. Ultimately, the functioning information obtained with the tool could be used to promote patient-centered ear and hearing care taking a biopsychosocial perspective into account.

Experienced clinicians derive many diagnoses intuitively, because most new problems they see closely resemble problems they've seen before. The majority of these diagnoses, but not all, will be correct. This study determined whether further reflection regarding initial diagnoses improves diagnostic accuracy during a high-stakes board exam, a model for studying clinical decision making. Keystroke response data were used from 500 residents who took the 2010 American Board of Internal Medicine (ABIM) Internal Medicine Certification Examination. Data included time to initial response on each question, whether the answer was correct, and whether or not the resident changed her or his initial response. The focus was on 80 diagnosis questions that comprised realistic clinical vignettes with multiple-choice single-best answers. Cognitive skill (ability) was measured using overall exam scores. Case complexity was determined using item difficulty (proportion of examinees that correctly answered the question). A hierarchical generalized linear model was used to assess the relationship between time spent on initial responses and the probability of correctly answering the questions. On average, residents changed their responses on 12% of all diagnosis questions (or 9.6 questions out of 80). Changing an answer from incorrect to correct was almost twice as likely as changing an answer from correct to incorrect. The relationship between response time and accuracy was complex. Further reflection appears to be beneficial to diagnostic accuracy, especially for more complex cases.

Invited commentary

Mutagenic repair of a ZFN-induced double-strand break in yeast: Effects of cleavage site sequence and spacer size

Large-scale semantic norms have become both prevalent and influential in recent psycholinguistic research. However, little attention has been directed towards understanding the methodological best practices of such norm collection efforts. We compared the quality of semantic norms obtained through rating scales, numeric estimation, and a less commonly used judgment format called best-worst scaling. We found that best-worst scaling usually produces norms with higher predictive validities than other response formats, and does so requiring less data to be collected overall. We also found evidence that the various response formats may be producing qualitatively, rather than just quantitatively, different data. This raises the issue of potential response format bias, which has not been addressed by previous efforts to collect semantic norms, likely because of previous reliance on a single type of response format for a single type of semantic judgment. We have made available software for creating best-worst stimuli and scoring best-worst data. We also made available new norms for age of acquisition, valence, arousal, and concreteness collected using best-worst scaling. These norms include entries for 1,040 words, of which 1,034 are also contained in the ANEW norms (Bradley & Lang, Affective norms for English words (ANEW): Instruction manual and affective ratings (pp. 1-45). Technical report C-1, the center for research in psychophysiology, University of Florida, 1999).

The purpose of the present studies was to assess the validity of using closed-set response formats to measure two cognitive processes essential for recognizing spoken words---perceptual normalization (the ability to accommodate acoustic-phonetic variability) and lexical discrimination (the ability to isolate words in the mental lexicon). In addition, the experiments were designed to examine the effects of response format on evaluation of these two abilities in normal-hearing (NH), noise-masked normal-hearing (NMNH), and cochlear implant (CI) subject populations. The speech recognition performance of NH, NMNH, and CI listeners was measured using both open- and closed-set response formats under a number of experimental conditions. To assess talker normalization abilities, identification scores for words produced by a single talker were compared with recognition performance for items produced by multiple talkers. To examine lexical discrimination, performance for words that are phonetically similar to many other words (hard words) was compared with scores for items with few phonetically similar competitors (easy words). Open-set word identification for all subjects was significantly poorer when stimuli were produced in lists with multiple talkers compared with conditions in which all of the words were spoken by a single talker. Open-set word recognition also was better for lexically easy compared with lexically hard words. Closed-set tests, in contrast, failed to reveal the effects of either talker variability or lexical difficulty even when the response alternatives provided were systematically selected to maximize confusability with target items. These findings suggest that, although closed-set tests may provide important information for clinical assessment of speech perception, they may not adequately evaluate a number of cognitive processes that are necessary for recognizing spoken words. The parallel results obtained across all subject groups indicate that NH, NMNH, and CI listeners engage similar perceptual operations to identify spoken words. Implications of these findings for the design of new test batteries that can provide comprehensive evaluations of the individual capacities needed for processing spoken language are discussed.

Immediate learner repair and its relationship with learning targeted forms in dyadic interaction

PurposeThe purpose of this paper is to identify the initial emergency response time of fire fighting teams in Malaysia.Design/methodology/approachIn an emergency incident time is of the essence, and the basic philosophy of an emergency response agency is to respond as quickly as possible to minimize the loss of life and property damage. In the current study, emergency response performance refers to team members' speed in responding to emergency situations, which was measured as the time taken for the team members to get to the fire truck from the waiting room in selected fire stations in Malaysia. The data collection period lasted for five months.FindingsThis study found that the overall average initial emergency response time was 84 seconds, while the overall average weighted initial emergency response time was 3.71 seconds per meter. The current study has demonstrated that the average initial emergency response performed by fire fighting teams in Malaysia is apparently better than that reported by previous studies by other emergency responders.Originality/valueThis paper presents empirical evidence of the initial emergency response time of fire fighters in Malaysia, by taking into account the distance traveled by the responders. As such, the performance measure obtained gives a meaningful indicator. The finding of the current study is then compared to emergency response performance by other emergency response agencies in other countries.

A comparison of frame-of-reference and frequency-based personality measurement

Membrane resealing in mammalian cells after injury depends on Ca(2+)-dependent fusion of intracellular vesicles with the plasma membrane. When cells are wounded twice, the subsequent resealing is generally faster. Physiological and biochemical studies have shown the initiation of two different repair signaling pathways, which are termed facilitated and potentiated responses. The facilitated response is dependent on the generation and recruitment of new vesicles, whereas the potentiated response is not. Here, we report that the two responses can be differentially defined molecularly. Using recombinant fragments of synaptobrevin-2 and synaptotagmin C2 domains we were able to dissociate the molecular requirements of vesicle exocytosis for initial membrane resealing and the facilitated and potentiated responses. The initial resealing response was blocked by fragments of synaptobrevin-2 and the C2B domain of synaptotagmin VII. Both the facilitated and potentiated responses were also blocked by the C2B domain of synaptotagmin VII. Although the initial resealing response was not blocked by the C2AB domain of synaptotagmin I or the C2A domain of synaptotagmin VII, recruitment of new vesicles for the facilitated response was inhibited. We also used Ca2+ binding mutant studies to show that the effects of synaptotagmins on membrane resealing are Ca(2+)-dependent. The pattern of inhibition by synaptotagmin C2 fragments that we observed cannot be used to specify a vesicle compartment, such as lysosomes, in membrane repair.

The purpose of this study was to investigate the prevalence of creaky voice in sentence-final position as a function of semantic predictability of the final word. Creaky voice is maligned in the media and often claimed to be less intelligible than normal phonation. A recent study finds some evidence to support this claim by examining intelligibility of single words. If speakers were concerned about intelligibility of their speech, they may be less likely to use it in sentences with little semantic support (e.g., “Mr. Black knew about the pad” compared to “Tear off some paper from the pad”). In the current study, 11 young female speakers without any vocal pathologies produced sentences from the Speech Perception in Noise (SPIN) test. Fourteen final words that appeared in both high and low semantic predictability sentences were selected for analysis. Three outcome measures were examined for these final words: presence versus absence of creaky voice, duration of creaky voice, and type of creaky voice. Contrary to our expectations, the results indicated that semantic support does not significantly predict the existence, amount, or type of creaky voice in young female speakers.

In this study, we examined the effects of response consensuality in syllogistic reasoning on patterns of answer change by using the two-response paradigm. Participants evaluated 24 syllogistic problems previously found to differ in consensuality, including consensually correct (CC), consensually wrong (CW), and nonconsensual (NC) items. Each problem was presented two times and participants were required to provide an initial quick answer to the first presentation, to rethink the problem, and to provide their second and final response without time limits to the second presentation. Participants reported the feeling-of-rightness (FOR) following the initial response, and the final judgment of confidence (FJC) after the final response. Following the assumptions of Koriat's (2012) Self-Consistency Model of confidence, we expected higher probability of answer change for initial nonconsensual responses than for initial consensual responses. The results showed that patterns of answer change, as well as metacognitive judgments and response times, were related to item consensus and response consensuality. Nonconsensual responses were more likely to be changed than consensual responses, and the probability of answer change correlated negatively with item consensus. Faster response times and higher FORs and FJCs were obtained for consensual and consistent responses than for nonconsensual and inconsistent responses. The obtained results indicate that answer change may in part be a consequence of random fluctuations in representation sampling, or in generating evidence that supports each of the two response options.