Process for a Reactive Monomer Alignment Layer for Liquid Crystals Formed on an Azodye Sublayer

In this work, the detailed studies of surface polymerization stabilizing liquid crystal formed on an azodye sublayer are presented. The surface localized stabilization is obtained by free-radical polymerization of a dilute solution of a bi-functional reactive monomer (RM) in a liquid crystal (LC) solvent. To optimize the process for surface localized stabilization, we investigate the effects of several process parameters including RM concentration in LC hosts, the types of materials (either RM or LC), the photo-initiator (PI) concentration, ultra-violet (UV) polymerization intensity, and the UV curing temperature. The quality of surface localized stabilization is characterized and/or evaluated by optical microscopy, electro-optical behavior (transmission/voltage curve), the life test, and photo-bleaching. Our results show that, by carefully selecting materials, formulating mixtures, and controlling the polymerizing variables, the RM polymerization can be realized either at the surface or through the bulk. Overall, the combination of surface localized stabilization and photo-alignment offers an elegant and dynamic solution for controlling the alignment for LC, which could play a profound role in almost all liquid crystal optical devices. Keywords: photoalignment; liquid crystals; reactive monomers; azo dyeUnited States. Army Research Office (Contract W911NF-14-1-0650

A Novel Drill Set for the Enhancement and Assessment of Robotic Surgical Performance

Background: There currently exist several training modules to improve performance during video-assisted surgery. The unique characteristics of robotic surgery make these platforms an inadequate environment for the development and assessment of robotic surgical performance. Methods: Expert surgeons (n=4) (greater than 50 clinical robotic procedures and greater than 2 years of clinical robotic experience) were compared to novice surgeons (n=17) (less than 5 clinical cases and limited laboratory experience) using the da Vinci Surgical System. Seven drills were designed to simulate clinical robotic surgical tasks. Performance score was calculated by the equation Time to Completion + (minor error) x 5 + (major error) x 10. The Robotic Learning Curve (RLC) was expressed as a trend line of the performance scores corresponding to each repeated drill. Results: Performance scores for experts were better than novices in all 7 drills (p less than 0.05). The RLC for novices reflected an improvement in scores (p less than 0.05). In contrast, experts demonstrated a flat RLC for 6 drills and an improvement in one drill (p=0.027). Conclusion: This new drill set provides a framework for performance assessment during robotic surgery. The inclusion of particular drills and their role in training robotic surgeons of the future awaits larger validation studies

Detecting Subtle Changes in Visuospatial Executive Function and Learning in the Amnestic Variant of Mild Cognitive Impairment

BACKGROUND AND PURPOSE: Amnestic mild cognitive impairment (aMCI) is a putative prodromal stage of Alzheimer's disease (AD) characterized by deficits in episodic verbal memory. Our goal in the present study was to determine whether executive dysfunction may also be detectable in individuals diagnosed with aMCI. METHODS: This study used a hidden maze learning test to characterize component processes of visuospatial executive function and learning in a sample of 62 individuals with aMCI compared with 94 healthy controls. RESULTS: Relative to controls, individuals with aMCI made more exploratory/learning errors (Cohen's d = .41). Comparison of learning curves revealed that the slope between the first two of five learning trials was four times as steep for controls than for individuals with aMCI (Cohen's d = .64). Individuals with aMCI also made a significantly greater number of rule-break/error monitoring errors across learning trials (Cohen's d = .21). CONCLUSIONS: These results suggest that performance on a task of complex visuospatial executive function is compromised in individuals with aMCI, and likely explained by reductions in initial strategy formulation during early visual learning and "on-line" maintenance of task rules

Histone H2B ubiquitylation disrupts local and higher-order chromatin compaction

Regulation of chromatin structure involves histone posttranslational modifications that can modulate intrinsic properties of the chromatin fiber to change the chromatin state. We used chemically defined nucleosome arrays to demonstrate that H2B ubiquitylation (uH2B), a modification associated with transcription, interferes with chromatin compaction and leads to an open and biochemically accessible fiber conformation. Notably, these effects were specific for ubiquitin, as compaction of chromatin modified with a similar ubiquitin-sized protein, Hub1, was only weakly affected. Applying a fluorescence-based method, we found that uH2B acts through a mechanism distinct from H4 tail acetylation, a modification known to disrupt chromatin folding. Finally, incorporation of both uH2B and acetylated H4 resulted in synergistic inhibition of higher-order chromatin structure formation, possibly a result of their distinct modes of action

The Effectiveness of Pharmacological and Non-Pharmacological Interventions for Improving Glycaemic Control in Adults with Severe Mental Illness: A Systematic Review and Meta-Analysis

People with severe mental illness (SMI) have reduced life expectancy compared with the general population, which can be explained partly by their increased risk of diabetes. We conducted a meta-analysis to determine the clinical effectiveness of pharmacological and non-pharmacological interventions for improving glycaemic control in people with SMI (PROSPERO registration: CRD42015015558). A systematic literature search was performed on 30/10/2015 to identify randomised controlled trials (RCTs) in adults with SMI, with or without a diagnosis of diabetes that measured fasting blood glucose or glycated haemoglobin (HbA1c). Screening and data extraction were carried out independently by two reviewers. We used random effects meta-analysis to estimate effectiveness, and subgroup analysis and univariate meta-regression to explore heterogeneity. The Cochrane Collaboration’s tool was used to assess risk of bias. We found 54 eligible RCTs in 4,392 adults (40 pharmacological, 13 behavioural, one mixed intervention). Data for meta-analysis were available from 48 RCTs (n = 4052). Both pharmacological (mean difference (MD), -0.11mmol/L; 95% confidence interval (CI), [-0.19, -0.02], p = 0.02, n = 2536) and behavioural interventions (MD, -0.28mmol//L; 95% CI, [-0.43, -0.12], p<0.001, n = 956) were effective in lowering fasting glucose, but not HbA1c (pharmacological MD, -0.03%; 95% CI, [-0.12, 0.06], p = 0.52, n = 1515; behavioural MD, 0.18%; 95% CI, [-0.07, 0.42], p = 0.16, n = 140) compared with usual care or placebo. In subgroup analysis of pharmacological interventions, metformin and antipsychotic switching strategies improved HbA1c. Behavioural interventions of longer duration and those including repeated physical activity had greater effects on fasting glucose than those without these characteristics. Baseline levels of fasting glucose explained some of the heterogeneity in behavioural interventions but not in pharmacological interventions. Although the strength of the evidence is limited by inadequate trial design and reporting and significant heterogeneity, there is some evidence that behavioural interventions, antipsychotic switching, and metformin can lead to clinically important improvements in glycaemic measurements in adults with SMI

A neurophysiological interpretation of the respiratory act

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/47945/1/10254_2005_Article_BF02320667.pd

Weed Busters: How to take the Kick out of Western Horse Nettle

trifold of 2 pp., 2 tables, 2 illustrationsWestern horse nettle is a weedy perennial in the nightshade family. Ranchers need to control it with herbicides to prevent livestock from ingesting poison that the weed produces. This publication specifies various herbicide options and the application rates for each one

Weed Busters: How to take the Sting out of Texas Bull Nettle

2 pages, 2 tables, 2 illustrationsTexas Cooperative Extension and the Texas Agricultural Experiment Station have developed, tested and approved two three-step ways to control Texas bull nettle. This publication explains how you can effectively deal with this native Texas plant and still be environmentally responsible at the same time

Disulfide-directed histone ubiquitylation reveals plasticity in hDot1L activation

We have developed a readily accessible disulfide-directed methodology for the site-specific modification of histones by ubiquitin and ubiquitin-like proteins. The disulfide-linked analog of mono-ubiquitylated H2B stimulated the H3K79 methyltransferase activity of hDot1L to a similar extent as the native isopeptide linkage. This permitted structure-activity studies of ubiquitylated mononucleosomes that revealed plasticity in the mechanism of hDot1L stimulation and identified surfaces of ubiquitin important for activation

A semisynthetic strategy to generate phosphorylated and acetylated histone H2B

Proteins are subject to numerous post-translational modifications (PTMs) that can alter the chemical structure, and hence function, of the molecule. The astonishing diversity of PTMs possible on proteins is exemplified by histones, nuclear proteins that form the protein core of the nucleosome particle. Histones can be modified in a variety of ways including acetylation, phosphorylation, methylation, ADP-ribosylation and ubiquitylation. Moreover, many, if not all, of these modifications can occur in combination. Indeed, there is growing evidence that functional cross-talk between histone PTMs is essential for the regulation of gene expression and ultimately cell fate and identity. Biochemical studies into the role of histone PTMs are often confounded by the difficulty associated with obtaining large quantities of homogeneously modified proteins. For this reason chemical approaches to obtaining post-translationally modified histones have received considerable attention in recent years. Among the available strategies, the protein ligation approach, expressed protein ligation (EPL), offers the most flexibility in terms of the number and type of PTMs that can be incorporated. To date, EPL has been used to generate phosphorylated, acetylated, and methylated forms of histone H3, acetylated H4, and ubiquitylated H2B. Nonetheless, many modified histones have yet to be accessed using semi-synthesis. A notable case in point is the N-terminal region of H2B, which has been described to possess several PTMs, including (poly)lysine acetylation and serine 14 phosphorylation, which have been implicated in transcription and apoptotic chromatin compaction, respectively. Differentially modified semi-synthetic H2B analogs would be useful to assess the affect of acetylation on both antibody recognition as well as on the efficiency of phosphorylation. In this report, we describe a general semi-synthetic route to H2B that allows the installation of PTMs into an otherwise native polypeptide background