Reactions, Diffusion and Volume Exclusion in a Heterogeneous System of Interacting Particles

Complex biological and physical transport processes are often described through systems of interacting particles. Excluded-volume effects on these transport processes are well studied, however the interplay between volume exclusion and reactions between heterogenous particles is less well known. In this paper we develop a novel framework for modeling reaction-diffusion processes which directly incorporates volume exclusion. From an off-lattice microscopic individual based model we use the Fokker--Planck equation and the method of matched asymptotic expansions to derive a low-dimensional macroscopic system of nonlinear partial differential equations describing the evolution of the particles. A biologically motivated, hybrid model of chemotaxis with volume exclusion is explored, where reactions occur at rates dependent upon the chemotactic environment. Further, we show that for reactions due to contact interactions the appropriate reaction term in the macroscopic model is of lower order in the asymptotic expansion than the nonlinear diffusion term. However, we find that the next reaction term in the expansion is needed to ensure good agreement with simulations of the microscopic model. Our macroscopic model allows for more direct parameterization to experimental data than the models available to date.Comment: 13 pages, 4 figure

Preview Cues: Enhancing Access to Multimedia Content

We describe preview cues, a lightweight mechanism to assist exploration of multimedia content. A preview cue provides a preview of the kind of content/information associated with an area (as opposed to an instance) of a domain. Preview cues associate media files and their meta data with the label of a topic in a domain. A lightweight gesture such as brushing a cursor over a label initiates playback of the preview cue file associated with that label. With these cues, users can preview the type of content associated with an area of a domain in order to decide whether or not that area is of interest for further exploration before having to select it. In this paper we describe the preview cues mechanism. We look at one case study of an implementation of preview cues in the audio domain, and we present the results of a user study of preview cue deployment. We conclude with a discussion of issues for future research

Beyond Breastfeeding: Exploring the Influence of Maternal Control Over Child Health Behavior Among African American Women Infants and Children Nutritional Supplementation Program Participants

The health benefits of breastfeeding exceed well beyond the first few years of an infant\u27s life. Breast milk is often referred to as liquid gold because of its extensive protective properties that promote child growth and development. Unfortunately, African American women have the lowest breastfeeding rates compared to any other racial group. Given that African American children are disproportionately affected by the current obesity epidemic in the United States, there may be a link between a mother\u27s preference to breastfeed her infant and her influence over her child\u27s eating behaviors and physical activity levels. Guided by social cognitive theory, the purpose of this quantitative longitudinal study was to explore the association between exclusive breastfeeding and maternal control over childhood nutrition and physical activity among African American women and children enrolled in the Women Infants and Children Nutritional Supplementation Program (WIC). Secondary data were used from the Infant Feeding Practices II Survey and its Year 6 Follow Up. Crosstabulations were performed to assess the relationship between exclusive breastfeeding and maternal control over child health behaviors after 6 years. The null hypotheses were not rejected, as there was no relationship between exclusive breastfeeding and maternal control over physical activity or child eating behaviors. Findings revealed moderate to high levels of maternal control among WIC participants who breastfed for 3 months. This study may lead to positive social change by increasing the number of children who benefit from breast milk and improving childhood nutrition and physical activity, which will ultimately reduce child obesity disparities and promote maternal and child health altogether

Optimizing rearing and welfare in Senegalese sole (Solea senegalesensis) broodstock: effect of ambient light intensity and handling time on stress response

Broodstock rearing conditions and handling procedures should be optimized in aquaculture species in order to benefit fish welfare and guarantee optimal conditions for spawning. In teleosts, basal cortisol levels display daily rhythms, oscillating along the 24 h of the day. In this sense, handling fish at different moments of the day may lead to different stress responses. The present study aimed at investigating the optimal rearing conditions for Senegalese sole broodstock, considering ambient light intensity and handling time. The optimal light intensity (50, 100 or 200 lx) was investigated by measuring fish cortisol levels and monitoring locomotor activity rhythms under each intensity tested. Results showed a significant increase in cortisol levels of fish exposed to 200 lx, when compared to values obtained under 100 lx, accompanied by changes in locomotor activity rhythms in both tanks under study. These results suggested that 200 lx may be too high as light intensity for this species, whereas 100 lx seems to be more adequate. Also, daily rhythms of stress response were investigated in breeders from different origins (Wild and first generation, G1). Basal cortisol levels and cortisol stress response after an acute stressor (air exposure) were monitored at two distinct moments of the day (Mid-Light and Mid-Dark). Basal levels were higher during the day in the wild group, while G1 fish seemed to have lost the daily fluctuations in basal cortisol plasma levels, as well as their daily rhythms of locomotor activity. Both groups showed lower stress responses during night-time, an indication that this is an adequate period of the day to handle this species. Senegalese sole breeders born in captivity presented more pronounced stress responses when compared to wild fish, reflecting their different life history in terms of stress challenges.FP7/SME/2008/1; UID/Multi/04326/2019; DL 57/2016/CP1361/CT0007; DL 57/2016/CP1361/CT0033info:eu-repo/semantics/publishedVersio

Tofacitinib in the management of active psoriatic arthritis: patient selection and perspectives.

Tofacitinib is an oral Janus kinase inhibitor approved for the treatment of psoriatic arthritis (PsA). It provides an alternative option for patients who have had an inadequate response and tolerance to other disease modifying antirheumatic drugs (DMARDs). It has demonstrated comparable efficacy to biologics, is effective in the management of treatment resistant disease, and is reported to improve enthesitis, dactylitis, and radiographic progression. Tofacitinib is also associated with an increased risk of serious infections, malignancy, and laboratory abnormalities. There is currently a large armamentarium of therapies for psoriatic arthritis, and choosing among treatments can be challenging. Due to this wide selection, a thorough assessment of psoriatic disease phenotype, patient preference, disease presentation, and comorbidities is critical. This review addresses key considerations in patient selection for the treatment of PsA with tofacitinib

Galcanezumab in episodic migraine: subgroup analyses of efficacy by high versus low frequency of migraine headaches in phase 3 studies (EVOLVE-1 & EVOLVE-2).

BACKGROUND: Patients with high-frequency episodic migraine (HFEM) have a greater disease burden than those with low-frequency episodic migraine (LFEM). Acute treatment overuse increases the risk of migraine chronification in patients with HFEM. Galcanezumab, a humanized monoclonal antibody binding calcitonin gene-related peptide (CGRP), is effective for migraine prevention with a favorable safety profile. Here, we investigate whether there are differences in galcanezumab efficacy in patients with LFEM or with HFEM. METHODS: Data were pooled from two double-blind, placebo-controlled phase 3 trials; EVOLVE-1 and EVOLVE-2. Patients were 18-65 years old, experienced 4-14 monthly migraine headache days (MHDs) for ≥1 year prior, with onset at \u3c 50 years of age. Migraine headaches were tracked via electronic patient-reported outcome system and randomization was stratified by low (LFEM; 4-7 monthly MHDs) or high (HFEM; 8-14 monthly MHDs) frequency. Subgroup analysis compared the HFEM and LFEM subgroups with a linear or generalized linear mixed model repeated measures approach. RESULTS: The intent-to-treat patients (N = 1773) had a mean age of 41.3 years, were mostly white (75%), female (85%), and 66% of patients had HFEM. In both the LFEM and HFEM subgroups, the overall (Months 1-6) and monthly changes from baseline in monthly MHDs and monthly MHDs with acute medication use compared with placebo were statistically significantly reduced for galcanezumab 120-mg and 240-mg. Galcanezumab (120-mg and 240-mg) significantly decreased the overall and monthly MHDs with nausea and/or vomiting, and with photophobia and phonophobia versus placebo in patients with LFEM or HFEM. In both subgroups, the mean overall (Months 1-6) and monthly percentages of patients with ≥50%, ≥75%, and 100% reduction in monthly MHDs from baseline were statistically significantly greater in patients receiving either dose of galcanezumab versus placebo. Galcanezumab (120-mg and 240-mg) significantly improved the Migraine-Specific Quality of Life Questionnaire role function-restrictive domain score as well as the Migraine Disability Assessment total score versus placebo for patients with LFEM or HFEM. There were no significant subgroup-by-treatment interactions. CONCLUSIONS: Galcanezumab was as effective in patients with HFEM as in those with LFEM. Associated symptoms, quality of life, and disability were similarly improved in patients with HFEM or LFEM. TRIAL REGISTRATION: NCT02614183 , NCT02614196

Different intra- and inter-molecular hydrogen-bonding patterns in (3S,4aS,8aS)-2-[(2R,3S)-3-(2,5-X2-benzamido)-2-(2,5-X2-benzo-yloxy)-4-phenyl-butyl]-N-tert-butyldeca-hydro-iso-quinoline-3-carboxamides (X = H or Cl) : compounds with moderate aspartyl protease inhibition activity

We thank the EPSRC National Crystallography Service (University of Southampton) for the X-ray data collections.Peer reviewedPublisher PD

Supporting Student Nurses By The Educational Use of Self: A Hermeneutic Phenomenological Exploration of the Mentor Experience

This thesis reports on a study of the lived experience of clinical nurses as mentors of student nurses in the workplace. Pre-registration nurse education, in which students must spend fifty percent of their time in practice, relies on a partnership between universities and health care providers and, crucially, the availability of practice mentors, able to support and assess practice learning. Within a hermeneutic phenomenological research methodology, twelve nurses described their experiences of mentoring through conversational interviews and event diaries which included ‘rich pictures’. The mixed methods provided openings for participants to talk about the harder-to-access elements of experience and generated multiple layers of rich data. Analysis of the data involved the application of different interpretive lenses: existentials in the care structure of Heidegger’s (1962) Dasein and the four lifeworld existentials (van Manen, 1997). For these respondents, the mentoring experience was rewarding, satisfying, frustrating, and even distressing at times. Being a mentor meant existing in worlds of ‘high stakes’, ‘hope for the nursing profession’ and ‘fragments’, governed by resource constraints, contextual demands and concern for others. Educational purposes dominated their being, revealing an essence, interpretively coined as ‘the educational use of self’, which meant that they were individually and authentically engaged in supporting and assessing learning. This study promotes greater understanding of mentoring practice and workplace learning, which can inform processes of recruitment, preparation and support of both students and mentors. Key insights are that mentors need support to work with complex and often hidden knowledge, including situations involving their intuitions