The correlation of Hammett substituent and Brownstein solvent constants with photochromic properties of triarylmethane dye leucocyanides

Five triarylmethane leucocyanides were synthesized from their parent dyes, and a photochromic test apparatus was designed and fabricated. The leucocyanides were tested for sensitivity and fade time in six solvents. The data was found to correlate well with Hammett substituent constants and with Brownstein solvent coefficients with certain exceptions

Lexical Frequency and Syntactic Variation: A Test of a Linguistic Hypothesis

The role of lexical frequency in language variation and change has received considerable attention in recent years. Recently Erker and Guy (2012) extended the analysis of frequency effects to morphosyntactic variation. Based on data from 12 Dominican and Mexican speakers from Otheguy and Zentella’s (2012) New York City Spanish corpus, they examined the role of frequency in variation between null and overt subject personal pronouns (SPP). Their results suggest that frequency either activates or amplifies the effects of other constraints such as co-reference. This paper attempts to replicate Erker and Guy’s study with a data set of Mexican immigrant and Mexican American Spanish. Analysis of more than 8,600 tokens shows that frequency has only a small effect on SPP use. In separate analyses of frequent and non-frequent verb forms, fewer constraints reach significance with frequent verb forms only than with non-frequent forms only. Moreover, in cases where constraints reach significance in both analyses, effects are stronger with non-frequent than with frequent forms. Finally, when all verb forms are combined in a single analysis, non-frequent forms are significantly more likely than frequent forms to co-occur with overt SPPs. We conclude that claims about frequency effects in SPP variation should be treated with caution and that further analyses are needed to establish whether models incorporating frequency can be extended to this area of the grammar

Attitudes towards Black American Sign Language

This paper explores how language attitudes and ideologies impact perceptions of language varieties in the American Deaf community, with a particular focus on Black ASL, the variety of ASL developed by African Americans in the South during the era of segregation. Results of multivariate analysis show that on a number of dimensions, Black ASL, particularly as used by signers who attended school before integration, is closer to the standard variety taught in ASL classes and used in ASL dictionaries. Nevertheless, despite evidence that their variety is closer to the standard taught in ASL classes, many of the older signers interviewed felt that white signing was superior. Attitudes among the younger signers were more mixed. While a few younger signers said that white signing was better than Black signing, others said that Black signing was more powerful in expression and movement and it had rhythm and style while white signing was more monotonic and lacked emotion. This paper explores the complex mix of attitudes expressed by study participants in the six Southern states in relation to the historical development of this distinctive variety of ASL

A mechanistic model of erythroblast growth inhibition: Optimising red blood cell manufacture

Manufacture of red blood cells (RBCs) from progenitors has been proposed as a method to reduce reliance on donors. Such a process would need to be extremely efficient for economic viability given a relatively low value product and high 2E12 cell dose. To achieve efficient process optimisation and scale-up an integrated approach comprising both experimentation and modelling is required. Using an automated stirred tank micro-bioreactor (ambr®, Sartorius Stedim, UK) we have shown that initially erythroblasts rapidly proliferate but then enter an inhibited growth phase. Experimentally we have confirmed that the conventional constraints on cell manufacturing efficiency, such as mass transfer, common metabolic limitations, or previously reported paracrine signals were not responsible for this inhibition. To further understand the mechanisms underlying the growth inhibition, we have used our own novel software interface, designed for the description, testing and manipulation of hypothetical dynamic mechanistic models. CD34+ cells derived from cord blood were grown in culture under erythroid expansion conditions. Cells were transferred to fresh culture medium and subject to different operating conditions. High time resolution growth curves were generated for each condition to distinguish between alternative models of growth and inhibition. The software, along with the experimental data, enabled a series of hypotheses regarding the mechanism of inhibition to be tested via the development of incrementally more complex mechanistic models based on the dominant phenomena involved in cell culture (e.g. substrate-dependent growth, cell death). Further experiments were performed under different operational conditions to test the predictive capabilities of the model and allow optimisation. These iterations produced a relatively simple deterministic mechanistic model based on inhibitor production and decay that could predict erythroblast growth behaviour as a consequence of medium provision and cell density strategy. We have described an experimentally efficient approach to model key cell growth behaviour and operational consequences for manufacturing, which has general relevance across therapeutic cell culture systems where feedback signals are prevalent. The approach supports a high degree of confidence in manufacturing control due to mechanistic underpinnings and is complimentary to a hypothesis driven approach to further understand influences of cell growth

Effect of expectoration on inflammation in induced sputum in α-1-antitrypsin deficiency

SummaryIt is unclear how chronic expectoration influences airway inflammation in patients with chronic lung disease. The aim of this study was to investigate factors influencing inflammation in induced sputum samples, including, in particular, chronic sputum production. Myeloperoxidase, interleukin-8, leukotriene B4 (LTB4), neutrophil elastase, secretory leukoprotease inhibitor (SLPI) and protein leakage were compared in induced sputum samples from 48 patients (36 with chronic expectoration) with COPD (with and without alpha-1-antitrypsin deficiency; AATD), 9 individuals with AATD but without lung disease and 14 healthy controls. There were no differences in inflammation in induced sputum samples from healthy control subjects and from AATD deficient patients with normal lung function but without chronic expectoration (P>0.05). Inflammation in induced sputum from AATD patients with airflow obstruction and chronic sputum expectoration was significantly greater than for similar patients who did not expectorate: Interleukin-8 (P<0.01), elastase activity (P=0.01), and protein leakage (P<0.01). The presence of spontaneous sputum expectoration in AATD patients with airflow obstruction was associated with increased neutrophilic airway inflammation in induced sputum samples. The presence of chronic expectoration in some patients will clearly complicate interpretation of studies employing sputum induction where this feature has not been identified

INCOG 2.0 Guidelines for Cognitive Rehabilitation Following Traumatic Brain Injury, Part III: Executive Functions

Introduction: Moderate-to-severe traumatic brain injury (MS-TBI) causes debilitating and enduring impairments of executive functioning and self-awareness, which clinicians often find challenging to address. Here, we provide an update to the INCOG 2014 guidelines for the clinical management of these impairments. Methods: An expert panel of clinicians/researchers (known as INCOG) reviewed evidence published from 2014 and developed updated recommendations for the management of executive functioning and self-awareness post-MS-TBI, as well as a decision-making algorithm, and an audit tool for review of clinical practice. Results: A total of 8 recommendations are provided regarding executive functioning and self-awareness. Since INCOG 2014, 4 new recommendations were made and 4 were modified and updated from previous recommendations. Six recommendations are based on level A evidence, and 2 are based on level C. Recommendations retained from the previous guidelines and updated, where new evidence was available, focus on enhancement of self-awareness (eg, feedback to increase self-monitoring; training with video-feedback), meta-cognitive strategy instruction (eg, goal management training), enhancement of reasoning skills, and group-based treatments. New recommendations addressing music therapy, virtual therapy, telerehabilitation-delivered metacognitive strategies, and caution regarding other group-based telerehabilitation (due to a lack of evidence) have been made. Conclusions: Effective management of impairments in executive functioning can increase the success and well-being of individuals with MS-TBI in their day-to-day lives. These guidelines provide management recommendations based on the latest evidence, with support for their implementation, and encourage researchers to explore and validate additional factors such as predictors of treatment response