Exploring protein-RNA interactions with site-directed mutagenesis and phage display

The importance of RNA as a mediator of genetic information is widely appreciated. RNA molecules also participate in the regulation of various post-transcriptional activities, such as mRNA splicing, editing, RNA stability and transport. Their regulatory roles for these activities are highly dependent on finely tuned associations with cognate proteins. The RNA recognition motif (RRM) is an ancient RNA binding module that participates in hundreds of essential activities where specific RNA recognition is required. We have applied phage display and site-directed mutagenesis to dissect principles of RRM-controlled RNA recognition. The model systems we are investigating are U1A and CUG-BP1. In this dissertation, the molecular basis of the binding affinity of U1A-RNA beyond individual contacts was investigated. We have identified and evaluated the contributions of the local cooperativity formed by three neighboring residues (Asn15, Asn16 and Glu19) to the stability of the U1A-RNA complex. The localized cooperative network was mapped by double-mutant cycles and explored using phage display. We also showed that a cluster of these residues forms a “hot spot” on the surface of U1A; a single substitution at position 19 with Gln or His can alter the binding properties of U1A to recognize a non-cognate G4U RNA. Finally, we applied a deletion analysis of CUG-BP1 to define the contributions of individual RRMs and RRM combinations to the stability of the complex formed between CUG-BP1 and the GRE sequence. The preliminary results showed RRM3 of CUG-BP1 is a key domain for RNA binding. It possibly binds to the GRE sequence cooperatively with RRM2 of CUG-BP1. RRM1 of CUG-BP1 is not required for GRE recognition, but may be important for maintaining the stability of the full-length CUG-BP1.

Nutrition and health claims in products directed at children via television in Spain in 2012

Objective: To describe the use of nutrition and health claims in products directed at children via television in Spain and to analyse their nutrient profile. Methods: A cross-sectional study of television food advertisements over 7 days in five Spanish television channels popular among children. The products were classified as core, non-core or miscellaneous, and as either healthy or less healthy, according to the United Kingdom Nutrient Profile Model. We registered all claims contained on the product (packaging and labelling) and its advertisement. We calculated the frequency distributions of health and nutrition claims. Results: During the 420 hours of broadcasting, 169 food products were identified, 28.5% in the dairy group and 60.9% in the non-core category. A total of 53.3% of products contained nutrition claims and 26.6% contained health claims; 62.2% of the products with claims were less healthy. Low-fat dairy products were the food category containing the highest percentage of health and nutrition claims. Conclusion: Over half of all food products marketed to children via television in Spain made some type of nutrition or health claim. Most of these products were less healthy, which could mislead Spanish consumers.

Event-Code Interaction Directed Test Cases

The Graphical User Interface (GUI) is an integral component of contemporary computer software. A stable and reliable GUI is necessary for correct functioning of software applications. Comprehensive verification of the GUI is a routine part of most software development life-cycles. The input space of a GUI is typically large, making exhaustive verification difficult. GUI defects are often revealed by exercising parts of the GUI that interact with each other. It is challenging for a verification method to drive the GUI into states that might contain defects. In recent years, model-based methods, that target specific GUI interactions, have been developed. These methods create a formal model of the GUI’s input space from specification of the GUI, visible GUI behaviors and static analysis of the GUI’s program-code. GUIs are typically dynamic in nature, whose user-visible state is guided by underlying program-code and dynamic program-state. This research extends existing model-based GUI testing techniques by modelling interactions between the visible GUI of a GUI-based software and its underlying program-code. The new model is able to, efficiently and effectively, test the GUI in ways that were not possible using existing methods. The thesis is this: Long, useful GUI testcases can be created by examining the interactions between the GUI, of a GUI-based application, and its program-code. To explore this thesis, a model-based GUI testing approach is formulated and evaluated. In this approach, program-code level interactions between GUI event handlers will be examined, modelled and deployed for constructing long GUI testcases. These testcases are able to drive the GUI into states that were not possible using existing models. Implementation and evaluation has been conducted using GUITAR, a fully-automated, open-source GUI testing framework.

Perceptions of Social Supports and Services for Intimate Partner Violence Victims

Intimate partner violence (IPV) is a complex issue. The present study explored how media exposure to female and male victims of IPV affected participants’ support for both groups. It was hypothesized that female victims would be supported more than male victims and that presenting stimuli that drew attention to male victims would not decrease support for female victims. Participants were presented with one of three posters, drawing attention to male victims, female victims, or both. A questionnaire was then used to assess perceptions of support for IPV victims, which was completed by 121 participants. Results indicated that females were supported more than males and that drawing attention to male victims did not decrease participants’ support for female victims. An exploratory analysis also revealed that women, overall, have high support for all victims, while men’s level of support changed depending on the type of information to which they were exposed.

Exploring the Process of Meaning-making after Partner Suicide

Meaning-making is increasingly recognized as a fundamental aspect of the grief experience. This study investigated the process of meaning-making in the narratives of individuals whose partners died by suicide, exploring their meaning reconstruction in response to this form of loss. The narratives of users of a public online grief support forum (n = 50) were analyzed using the Meaning of Loss Codebook (Gillies, Neimeyer, & Milman, 2014), which consists of core categories of meaning of loss in response to the death of a loved one. The results indicated that these individuals predominantly experienced negative affect, a lack of understanding associated with the loss, and a longing for their partners. The grief experience of participants in this study was marked by substantial psychological distress and an ongoing struggle to make sense of and find meaning in this type of loss. It is clear that grieving the loss of a partner as a result of suicide presents unique challenges to meaning-making in comparison to other types of loss. Given the importance of this aspect of adjustment to loss, these findings deepen the understanding of this component of grief and inform the provision of support for those grieving a loved one who died by suicide.

A communication partner training program: Assessing conversational behaviors and attitudes towards communication in Persons with Aphasia and their Communication Partners

This study examined the conversational behaviors of eleven dyads consisting of a person with aphasia (PWA) and their familiar communication partner (CP), and investigated changes in behaviors as a result of attending a communication partner-training program CPT). Attitudes about communication were examined and related to conversational behaviors observed pre- and post- training. Results indicated that CPs and PWA used significantly more facilitating behaviors than barrier behaviors, although most dyads experienced some barriers. A comparison of pre-and post-CPT conversations revealed a significant interaction between time and type of behavior, with the increase in the number of facilitators approaching significance. Overall, persons with aphasia and their conversational partners expressed positive attitudes about communication. There were no significant correlations between scores on attitude surveys and behaviors pre or post-training. This study demonstrated that these dyads employed facilitative conversational behaviors even before CPT, and that facilitative behaviors can increase after a one-day training workshop.

DOCUMENTARY DIRECTED PRACTICE CONTROL IN CANTON PURISCAL, SAN JOSE, COSTA RICA

The Directed Practice Seminar was developed under the theme Document Control in Canton Puriscal, San Jose Costa Rica. The practice consisted of a process of identification, collection, description, analysis and typing of documents Puriscal of historical, scientific and cultural, to publicize the county's documentary heritage, thus contributing to the Costa Rican national literature, and also promote the rescue culture of the peoples, a task that performs modern librarianship.The search, identification and collection of documents that have been published or not, in and to the Canton Puriscal was thorough and in all possible formats: books, journals, letters, brochures, memos, videos, newspaper articles, manuscripts , periodicals, electronic resources, among others.

Controlling Pattern Formation in Nanoparticle Assemblies via Directed Solvent Dewetting

We have achieved highly localised control of pattern formation in two dimensional nanoparticle assemblies by direct modification of solvent dewetting dynamics. A striking dependence of nanoparticle organisation on the size of atomic force microscope-generated surface heterogeneities is observed and reproduced in numerical simulations. Nanoscale features induce rupture of the solvent-nanoparticle film, causing the local flow of solvent to carry nanoparticles into confinement. Microscale heterogeneities instead slow the evaporation of the solvent, producing a remarkably abrupt interface between different nanoparticle patterns.

Fueling growth when oil peaks: directed technological change and the limits to efficiency

While fossil energy dependency has declined and energy supply has grown in the postwar world economy, future resource scarcity could cast its shadow on world economic growth soon if energy markets are forward looking. We develop an endogenous growth model that reconciles the current aggregate trends in energy use and productivity growth with the intertemporal dynamics of forward looking resource markets. Combining scarcity-rent driven energy supply (in the spirit of Hotelling) with profit-driven Directed Technical Change (in the spirit of Romer/Acemoglu), we generate transitional dynamics that can be qualitatively calibrated to current trends. The long-run properties of the model are studied to examine whether current trends are sustainable. We highlight the role of extraction costs in mining.

Testosterone and attention deficits as possible mechanisms underlying impaired emotion recognition in intimate partner violence perpetrators

Several studies have reported impairments in decoding emotional facial expressions in intimate partner violence (IPV) perpetrators. However, the mechanisms that underlie these impaired skills are not well known. Given this gap in the literature, we aimed to establish whether IPV perpetrators (n = 18) differ in their emotion decoding process, attentional skills, and testosterone (T), cortisol (C) levels and T/C ratio in comparison with controls (n = 20), and also to examine the moderating role of the group and hormonal parameters in the relationship between attention skills and the emotion decoding process. Our results demonstrated that IPV perpetrators showed poorer emotion recognition and higher attention switching costs than controls. Nonetheless, they did not differ in attention to detail and hormonal parameters. Finally, the slope predicting emotion recognition from deficits in attention switching became steeper as T levels increased, especially in IPV perpetrators, although the basal C and T/C ratios were unrelated to emotion recognition and attention deficits for both groups. These findings contribute to a better understanding of the mechanisms underlying emotion recognition deficits. These factors therefore constitute the target for future interventions.

Women's disengagement from legal proceedings for intimate partner violence: sociodemographic and psychological variables

The aim of this study is to shed light on what makes women decide whether or not to continue with legal proceedings for intimate partner violence once they have commenced. Legal professionals, members of the police force, and women in Spain were interviewed to help draft a questionnaire that was applied to a sample of 345 women who had undertaken legal proceedings against their (ex)partners. Socio-demographic, emotional, and psychological variables were considered as possible predictor variables and included in a logistic regression analysis. Results show that the best equation for predicting disengagement from legal procedures includes the level of support received by the victim, contact with the aggressor, thoughts about going back with the aggressor, and a feeling of guilt. The essential role of the psychological support during the legal process is emphasized in conclusions.

Safety and risk factors for difficult endoscopist-directed ERCP sedation in daily practice: a hospital-based case-control study

Background: There are limited data concerning endoscopist-directed endoscopic retrograde cholangiopancreatography deep sedation. The aim of this study was to establish the safety and risk factors for difficult sedation in daily practice. Patients and methods: Hospital-based, frequency matched case-control study. All patients were identified from a database of 1,008 patients between 2014 and 2015. The cases were those with difficult sedations. This concept was defined based on the combination of the receipt of high-doses of midazolam or propofol, poor tolerance, use of reversal agents or sedation-related adverse events. The presence of different factors was evaluated to determine whether they predicted difficult sedation. Results: One-hundred and eighty-nine patients (63 cases, 126 controls) were included. Cases were classified in terms of high-dose requirements (n = 35, 55.56%), sedation-related adverse events (n = 14, 22.22%), the use of reversal agents (n = 13, 20.63%) and agitation/discomfort (n = 8, 12.7%). Concerning adverse events, the total rate was 1.39%, including clinically relevant hypoxemia (n = 11), severe hypotension (n = 2) and paradoxical reactions to midazolam (n = 1). The rate of hypoxemia was higher in patients under propofol combined with midazolam than in patients with propofol alone (2.56% vs. 0.8%, p < 0.001). Alcohol consumption (OR: 2.674 [CI 95%: 1.098-6.515], p = 0.030), opioid consumption (OR: 2.713 [CI 95%: 1.096-6.716], p = 0.031) and the consumption of other psychoactive drugs (OR: 2.015 [CI 95%: 1.017-3.991], p = 0.045) were confirmed to be independent risk factors for difficult sedation. Conclusions: Endoscopist-directed deep sedation during endoscopic retrograde cholangiopancreatography is safe. The presence of certain factors should be assessed before the procedure to identify patients who are high-risk for difficult sedation.

Maximizing HIV partner notification opportunities for index patients and their sexual partners in Malawi

Introduction HIV testing and counselling (HTC) is important to effect positive sexual behaviour change and is an entry point to treatment, care, and psychosocial support. One of the most practical initiatives to increase HTC is to encourage sexual partners of HIV-infected persons to test for HIV. However, partner notification strategies must be feasible in the healthcare setting and acceptable to the population. Methods We conducted a qualitative study during the pilot phase of an HIV partner notification trial to complement its assessment of feasibility and acceptability of methods of partner notification. We performed in-depth interviews with 16 consecutive HIV-positive index participants who consented and their 12 identifiable sexual partners. We also conducted two focus group discussions with healthcare workers to supplement the patient perspectives. In the main study, newly diagnosed HIV cases (index cases) were randomized to one of three methods of partner notification: passive, contract, and provider referral. Clients in the passive referral group were responsible for notifying their sexual partners themselves. Individuals in the contract referral group were given seven days to notify their partners, after which a healthcare provider contacted partners who had not reported for counselling and testing. In the provider group, a healthcare provider notified partners directly. Results Although most index participants and partners expressed a preference for passive notification, they also highlighted benefits for provider-assisted notification and the universal right for all HIV-exposed persons to know their HIV exposure and benefit from HIV testing and access antiretroviral treatment. Several participants mentioned couples counselling as a way to diffuse tension and get accurate information. All mentioned benefits to HIV testing, including the opportunity to change behaviour. Conclusions Provider-assisted partner notification is not preferred, but it is acceptable and may complement the passive method of notification. Couples counselling should also be encouraged.

SERR spectroelectrochemical study of cytochrome cd1 nitrite reductase co-immobilized with physiological redox partner cytochrome c552 on biocompatible metal electrodes

© 2015 Silveira et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.