Early language experience in a Tseltal Mayan village

Daylong at-home audio recordings from 10 Tseltal Mayan children (0;2–3;0; Southern Mexico) were analyzed for how often children engaged in verbal interaction with others and whether their speech environment changed with age, time of day, household size, and number of speakers present. Children were infrequently directly spoken to, with most directed speech coming from adults, and no increase with age. Most directed speech came in the mornings, and interactional peaks contained nearly four times the baseline rate of directed speech. Coarse indicators of children's language development (babbling, first words, first word combinations) suggest that Tseltal children manage to extract the linguistic information they need despite minimal directed speech. Multiple proposals for how they might do so are discussed

Turn taking, timing, and planning in early language acquisition

Young children answer questions with longer delays than adults do, and they don't reach typical adult response times until several years later. We hypothesized that this prolonged pattern of delay in children's timing results from competing demands: to give an answer, children must understand a question while simultaneously planning and initiating their response. Even as children get older and more efficient in this process, the demands on them increase because their verbal responses become more complex. We analyzed conversational question-answer sequences between caregivers and their children from ages 1;8 to 3;5, finding that children (1) initiate simple answers more quickly than complex ones, (2) initiate simple answers quickly from an early age, and (3) initiate complex answers more quickly as they grow older. Our results suggest that children aim to respond quickly from the start, improving on earlier-acquired answer types while they begin to practice later-acquired, slower ones

Standard and generalized McDonald–Kreitman test: a website to detect selection by comparing different classes of DNA sites

The McDonald and Kreitman test (MKT) is one of the most powerful and extensively used tests to detect the signature of natural selection at the molecular level. Here, we present the standard and generalized MKT website, a novel website that allows performing MKTs not only for synonymous and nonsynonymous changes, as the test was initially described, but also for other classes of regions and/or several loci. The website has three different interfaces: (i) the standard MKT, where users can analyze several types of sites in a coding region, (ii) the advanced MKT, where users can compare two closely linked regions in the genome that can be either coding or noncoding, and (iii) the multi-locus MKT, where users can analyze many separate loci in a single multi-locus test. The website has already been used to show that selection efficiency is positively correlated with effective population size in the Drosophila genus and it has been applied to include estimates of selection in DPDB. This website is a timely resource, which will presumably be widely used by researchers in the field and will contribute to enlarge the catalogue of cases of adaptive evolution. It is available at http://mkt.uab.es

"Call a Teenager… That's What I Do!" - Grandchildren Help Older Adults Use New Technologies: Qualitative Study.

BackgroundAlthough family technical support seems intuitive, there is very little research exploring this topic.ObjectiveThe objective of this study was to conduct a subanalysis of data collected from a large-scale qualitative project regarding older adults' experiences in using health information technology. Specifically, the subanalysis explored older adults' experiences with technology support from family members to inform strategies for promoting older adults' engagement with new health technologies. Although the primary analysis of the original study was theoretically driven, this paper reports results from an inductive, open-coding analysis.MethodsThis is a subanalysis of a major code identified unexpectedly from a qualitative study investigating older adults' use experience of a widespread health technology, the patient portal. A total of 24 older patients (≥65 years) with multiple chronic conditions (Charlson Comorbidity Index >2) participated in focus groups conducted at the patients' primary clinic. While conducting the primary theoretically driven analysis, coders utilized an open-coding approach to ensure important ideas not reflected in the theoretical code book were captured. Open coding resulted in 1 code: family support. This subanalysis further categorized family support by who provided tech support, how tech support was offered, and the opinions of older participants about receiving family tech support.ResultsThe participants were not specifically asked about family support, yet themes around family assistance and encouragement for technology emerged from every focus group. Participants repeatedly mentioned that they called their grandchildren and adult children if they needed help with technology. Participants also reported that family members experienced difficulty when teaching technology use. Family members struggled to explain simple technology tasks and were frustrated by the slow teaching process.ConclusionsThe results suggest that older adults ask their family members, particularly grandchildren, to support them in the use of new technologies. However, family may experience difficulties in providing this support. Older adults will be increasingly expected to use health technologies, and family members may help with tech support. Providers and health systems should consider potential family support and engagement strategies to foster adoption and use among older patients

The perception of stroke-to-stroke turn boundaries in signed conversation

Speaker transitions in conversation are often brief, with minimal vocal overlap. Signed languages appear to defy this pattern with frequent, long spans of simultaneous signing. But recent evidence suggests that turn boundaries in signed language may only include the content-bearing parts of the turn (from the first stroke to the last), and not all turn-related movement (from first preparation to final retraction). We tested whether signers were able to anticipate “stroke-to-stroke” turn boundaries with only minimal conversational context. We found that, indeed, signers anticipated turn boundaries at the ends of turn-final strokes. Signers often responded early, especially when the turn was long or contained multiple possible end points. Early responses for long turns were especially apparent for interrogatives—long interrogative turns showed much greater anticipation compared to short ones

Involvement of etfA gene during CaCO3 precipitation in Bacillus subtilis biofilm

The eftA gene in Bacillus subtilis has been suggested to be involved in the oxidation/reduction reactions during fatty acid metabolism. Interestingly etfA deletion in B. subtilis results in impairment in CaCO3 precipitation on the biofilm. Comparisons between the wild type B. subtilis 168 and its etfA mutant during in vitro CaCO3 crystal precipitation (calcite) revealed changes in phospholipids membrane composition with accumulation of up to 10% of anteiso-C17:0 and 11% iso-C17:0 long fatty acids. Ca2+ nucleation sites such as dipicolinic acid and teichoic acids seem to contribute to the CaCO3 precipitation. etfA mutant strain showed up to 40% less dipicolinic acid accumulation compared with B. subtilis 168, while a B. subtilis mutant impaired in teichoic acids synthesis was unable to precipitate CaCO3. In addition, B. subtilis etfA mutant exhibited acidity production leading to atypical flagella formation and inducing extensive lateral growth on the biofilm when grown on 1.4% agar. From the ecological point of view, this study shows a number of physiological aspects that are involved in CaCO3 organomineralization on biofilms

Perceptions of Caregiver Distress, Health Behaviors, and Provider Health-Promoting Communication and their Relationship to Stress Management in MS Caregivers

This study applied the Stress/Health Model to examine a novel approach for promoting stress management among 67 caregivers of persons with multiple sclerosis, who often face unique caregiving challenges. Hierarchical regressions indicated that caregiver distress (i.e., emotional burden) and engagement in other health-promoting activities (i.e., controlling alcohol use) were the best predictors of caregiver stress management. Communication with the MS care recipient’s health provider about caregiver engagement in health-promoting activities was associated with caregiver stress management, but not significantly more so than explained by the other factors (i.e., caregiver distress and engagement in health-promoting behaviors). A more controlled study would be indicated to further explain how to encourage, within the medical setting, caregiver engagement in self-care activities

Turn-timing in naturalistic mother-child interactions: A longitudinal perspective

Combining data from two longitudinal studies of young children, we track the development of turn-timing in spontaneous infant-caregiver interactions. We focus on three aspects of timing: overlap, gap, and delay marking. We find evidence for early development of turn-timing skills, in-line with the Interaction Engine Hypothesis. (see attached .pdf for our 2-page abstract