Recent advances in multidisciplinary optimization of rotorcraft

A joint activity involving NASA and Army researchers at NASA LaRC to develop optimization procedures to improve the rotor blade design process by integrating appropriate disciplines and accounting for all of the important interactions among the disciplines is described. The disciplines involved include rotor aerodynamics, rotor dynamics, rotor structures, airframe dynamics, and acoustics. The work is focused on combining these five key disciplines in an optimization procedure capable of designing a rotor system to satisfy multidisciplinary design requirements. Fundamental to the plan is a three-phased approach. In phase 1, the disciplines of blade dynamics, blade aerodynamics, and blade structure are closely coupled while acoustics and airframe dynamics are decoupled and are accounted for as effective constraints on the design for the first three disciplines. In phase 2, acoustics is integrated with the first three disciplines. Finally, in phase 3, airframe dynamics is integrated with the other four disciplines. Representative results from work performed to date are described. These include optimal placement of tuning masses for reduction of blade vibratory shear forces, integrated aerodynamic/dynamic optimization, and integrated aerodynamic/dynamic/structural optimization. Examples of validating procedures are described

Optically-induced lensing effect on a Bose-Einstein condensate expanding in a moving lattice

We report the experimental observation of a lensing effect on a Bose-Einstein condensate expanding in a moving 1D optical lattice. The effect of the periodic potential can be described by an effective mass dependent on the condensate quasi-momentum. By changing the velocity of the atoms in the frame of the optical lattice we induce a focusing of the condensate along the lattice direction. The experimental results are compared with the numerical predictions of an effective 1D theoretical model. Besides, a precise band spectroscopy of the system is carried out by looking at the real-space propagation of the atomic wavepacket in the optical lattice.Comment: 5 pages, 4 figures; minor changes applied and typos corrected; a new paragraph added; some references updated; journal reference adde

bak deletion stimulates gastric epithelial proliferation and enhances Helicobacter felis-induced gastric atrophy and dysplasia in mice

Helicobacter infection causes a chronic superficial gastritis that in some cases progresses via atrophic gastritis to adenocarcinoma. Proapoptotic bak has been shown to regulate radiation-induced apoptosis in the stomach and colon and also susceptibility to colorectal carcinogenesis in vivo. Therefore we investigated the gastric mucosal pathology following H. felis infection in bak-null mice at 6 or 48 wk postinfection. Primary gastric gland culture from bak-null mice was also used to assess the effects of bak deletion on IFN-γ-, TNF-α-, or IL-1β-induced apoptosis. bak-null gastric corpus glands were longer, had increased epithelial Ki-67 expression, and contained fewer parietal and enteroendocrine cells compared with the wild type (wt). In wt mice, bak was expressed at the luminal surface of gastric corpus glands, and this increased 2 wk post-H. felis infection. Apoptotic cell numbers were decreased in bak-null corpus 6 and 48 wk following infection and in primary gland cultures following cytokine administration. Increased gastric epithelial Ki-67 labeling index was observed in C57BL/6 mice after H. felis infection, whereas no such increase was detected in bak-null mice. More severe gastric atrophy was observed in bak-null compared with C57BL/6 mice 6 and 48 wk postinfection, and 76% of bak-null compared with 25% of C57BL/6 mice showed evidence of gastric dysplasia following long-term infection. Collectively, bak therefore regulates gastric epithelial cell apoptosis, proliferation, differentiation, mucosal thickness, and susceptibility to gastric atrophy and dysplasia following H. felis infection

How do speakers with and without aphasia use syntax and semantics across two discourse genres?

Background: Discourse is an increasing focus of assessment in clinical and research settings because it reflects everyday communication. Everyday communication is likely to include a range of different discourse genres, e.g. describing a scene, or reflecting on life experiences. It is likely that speakers use verbs differently in these different discourse genres, but very little is known about this. Aims: To explore whether there were differences in how two groups of speakers (with and without a communication impairment) used verbs in two different discourse genres, in terms of syntax and semantics. Methods & Procedures: Data from people with aphasia (PWA) were taken from an earlier study (Cruice and colleagues, 2010; 2014), and neurologically healthy people (NHP) were recruited for the current study. Participants produced discourses from two genres: a picture description (the Western Aphasia Battery ‘Picnic Scene’) and personal narrative (reflective responses to quality of life questions). Discourses were analysed using measures of argument structure (mean Predicate Argument Structure score), verb weight (% heavy verbs) and verb semantic category (% mental and relational verbs). Comparisons were made for each measure between genre and group using a series of two mixed two-way ANOVAs. Outcomes & results: Data from 26 PWA and 27 NHP were analysed. For PAS, there was a main effect of genre, significant interaction between group and genre, and main effect of group. For the semantic measures, there was a main effect of genre for % mental verbs but no effects or interactions for % heavy and % relational verbs. Post-hoc correlations explored associations between the variables. Conclusions: Genre exerts no demonstrable impact on semantic weight, in either speaker group, but does exert influence on the semantic category of verbs used because, for both speaker groups, the picture description genre elicited a smaller percentage of mental verbs than the personal narratives produced in response to QOL questions. For PWA only, genre also exerted an influence on argument structure, with QOL narratives eliciting significantly less complex argument structures. This has implications for clinical assessment. Discourses of different genres should be sampled to fully assess a speaker’s syntactic and lexico-semantic skills; and the genre of discourse used for assessment and therapy materials should align with the client’s communication goals

A genome-wide investigation of the worldwide invader Sargassum muticum shows high success albeit (almost) no genetic diversity

Twenty years of genetic studies of marine invaders have shown that successful invaders are often characterized by native and introduced populations displaying similar levels of genetic diversity. This pattern is presumably due to high propagule pressure and repeated introductions. The opposite pattern is reported in this study of the brown seaweed, Sargassum muticum, an emblematic species for circumglobal invasions. Albeit demonstrating polymorphism in the native range, microsatellites failed to detect any genetic variation over 1,269 individuals sampled from 46 locations over the Pacific-Atlantic introduction range. Single-nucleotide polymorphisms (SNPs) obtained from ddRAD sequencing revealed some genetic variation, but confirmed severe founder events in both the Pacific and Atlantic introduction ranges. Our study thus exemplifies the need for extreme caution in interpreting neutral genetic diversity as a proxy for invasive potential. Our results confirm a previously hypothesized transoceanic secondary introduction from NE Pacific to Europe. However, the SNP panel unexpectedly revealed two additional distinct genetic origins of introductions. Also, conversely to scenarios based on historical records, southern rather than northern NE Pacific populations could have seeded most of the European populations. Finally, the most recently introduced populations showed the lowest selfing rates, suggesting higher levels of recombination might be beneficial at the early stage of the introduction process (i.e., facilitating evolutionary novelties), whereas uniparental reproduction might be favored later in sustainably established populations (i.e., sustaining local adaptation).Agence Nationale de la Recherche - ANR-10-BTBR-04; European Regional Development Fund; Fundacao para a Ciencia e a Tecnologia - SFRH/BPD/107878/2015, UID/Multi/04326/2016, UID/Multi/04326/2019; Brittany Region;info:eu-repo/semantics/publishedVersio

Increasing the intensity and comprehensiveness of aphasia services: identification of key factors influencing implementation across six countries

Background: Aphasia services are currently faced by increasing evidence for therapy of greater intensity and comprehensiveness. Intensive Comprehensive Aphasia Programs (ICAPs) combine these elements in an evidence-based, time-limited group program. The incorporation of new service delivery models in routine clinical practice is, however, likely to pose challenges for both the service provider and administering clinicians. This program of research aims to identify these challenges from the perspective of aphasia clinicians from six countries and will seek to trial potential solutions. Continual advancements in global communication technologies suggest that solutions will be easily shared and accessed across multiple countries. Aims: To identify the perceived and experienced barriers and facilitators to the implementation of 1) intensive aphasia services, 2) comprehensive aphasia services, and 3) ICAPs, from aphasia clinicians across six countries. Methods and procedures: A qualitative enquiry approach included data from six focus groups (n = 34 participants) in Australia, New Zealand, Canada, United States of America (USA), United Kingdom (UK), and Ireland. A thematic analysis of focus group data was informed by the Theoretical Domains Framework (TDF). Outcomes and results: Five prominent theoretical domains from the TDF influenced the implementation of all three aphasia service types across participating countries: environmental context and resources, beliefs about consequences, social/professional role and identity, skills, and knowledge. Four overarching themes assisted the identification and explanation of the key barriers and facilitators: 1. Collaboration, joint initiatives and partnerships, 2. Advocacy, the promotion of aphasia services and evidence-based practice, 3. Innovation, the ability to problem solve challenges, and 4. Culture, the influence of underlying values. Conclusions: The results of this study will inform the development of a theoretically informed intervention to improve health services’ adherence to aphasia best practice recommendations

Cultural adaptation and psychometric testing of The Scenario Test UK for people with aphasia

BACKGROUND: This study explores the psychometric properties of The Scenario Test UK, a culturally adapted version of the Dutch original (The Scenario Test) developed by van der Meulen et al. in 2010, which evaluates functional, daily-life communication in aphasia. The Scenario Test assesses communication in an interactive context with a supportive communication partner. AIMS: To evaluate the reliability (internal consistency, interrater and test-retest reliability) and construct validity (convergent, discriminant and known-groups validity) of The Scenario Test UK. METHODS & PROCEDURES: The Scenario Test UK and other language, cognition and praxis assessments were administered to persons with aphasia after stroke (3+ months post-stroke) and to non-aphasic controls. Participants were recruited primarily through community stroke groups. Measures were completed in an interview format. Standard psychometric criteria were used to evaluate reliability and construct validity. OUTCOMES & RESULTS: A total of 74 participants with aphasia and 20 participants without aphasia took part in The Scenario Test UK. The test showed high levels of reliability. Internal consistency (Cronbach's α = 0.92), interrater reliability (ICC = 0.95) and test-retest reliability (ICC = 0.96) were excellent. Interrater agreement in scores on the individual items ranged from good to excellent (κ = 0.41-1.00) for all but two items (item 4c κ = 0.38, item 6c κ = 0.36). The test demonstrated good levels of convergent (ρ = 0.37-0.75) and discriminant validity (ρ = -0.04 to 0.23). There was strong evidence for known groups validity (U = 132.50, p < .001), with those with aphasia scoring significantly lower [median (interquartile range-IQR) = 47 (39.8-51.0)] than those without aphasia [53 (52-54)]. CONCLUSIONS & IMPLICATIONS: The data support the reliability and validity of the Scenario Test UK as an assessment of functional, daily-life communication for persons with aphasia. Further testing is needed in independent samples on the measure's psychometric properties, including its sensitivity to change. Pending this testing, The test can be used as an assessment tool to evaluate communication skills with people with aphasia, to guide goal setting for therapy and to measure outcomes in response to therapy

Reduced Cardiovascular Disease Deaths in 21 Western Countries 1989-91 V 2013-154: What is the UK doing Right or What is the USA doing Wrong?

Objectives: To compare UK Cardiovascular Disease Deaths (CDD) with twenty Other Western Countries (OWC). Design: Population-controlled-based study using WHO data on CDD people aged 55-74 and Age-Standardised-Death-Rates (ASDR) rates per million (pm) contrasts UK and OWC outcomes between 1989-2015 and World Bank % GDP Expenditure-on-Health (%GDPEH) data. Setting: Twenty-one Western Countries. Participants: National populations. Outcome measures: Reduced CDD for people aged 55-74 and ASDR confidence intervals determines statistical differences between UK and OWC over the period. Result: All countries substantially reduced CDD 55-74, highest current rates America at 3440pm, Finland 3197pm, Greece 3173 to lowest, France 1522pm, Australia 1634pm and Japan 1866pm. Previously UK was 4th highest but fell to 8th at 2524pm, significantly reducing CDD more than 15 OWC, though three had greater falls than Britain. ASDR fell substantially everywhere but the UK had second biggest reduction, significantly reducing total CDD deaths more than 15 OWC. Highest 1980-2015 average %GDPEH was USA at 12.7%, UK’s 7.6% was lowest suggesting British cardiac services achieved more with proportionately less. Conclusion: Improvements in primary and secondary prevention of cardiovascular disease occurred in every country, we speculate whether the UK success might be attributable to the Pan UK public health innovations, the National Service Framework (2000) to reduce myocardial infarction, and, National Framework for long term conditions (2005) but further research is required to identify the effective mechanisms. These results should be a morale boost for patients and their families and or all in the cardiac services, especially in the UK