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The continued integration of smaller, higher-functioning devices in the Aerospace, Defense & Space sectors is making it more challenging than ever to minimize assembly failure, especially where reliability is top priority and fail-safe processes, and materials are the standard. Assembly failures due to poor adhesive bonding tend to linger causing excessive manufacturing downtime, scrap, costly rework, and delays. This paper introduces the science behind adhesion. Regardless of the application, the market or the adhesive technology being used, such as epoxy, silicone, urethane, paste or film, achieving a proper assembly bond is critical for application success. Adhesion is achieved via two mechanisms, mechanical and chemical bonding. To optimize this the adhesive must flow (or wet) across the substrate. This maximizes the interaction between the adhesive and substrate allowing flow into microscopic substrate pores for enhanced mechanical bonding as well as interaction between adhesive and substrate for chemical bonding. The molecular force of attraction between an adhesive and the substrate is determined by the surface energy of the substrates. The substrate surface energy influences the ability of the adhesive to flow and wet the substrate impacting adhesion. Measuring substrate water contact angle is an easy method to determine the relative surface energy thereby gaining information about the pending adhesive bond. This paper reviews these key factors for adhesion and presents results of an application study aimed at understanding the sensitivity and relationship of substrate water contact angle versus substrate cleanliness. The goal is to be able to use substrate water contact angle measurements as a predictive tool for adhesion.

Background Although disparities in cancer rates, later diagnoses and lower survival rates between Indigenous and non-Indigenous people have been documented, little is known about how Indigenous patients with cancer encounter the health care system. We explored perceptions and experiences of Indigenous patients with cancer and their families to understand better how 2 key concepts - trust and world view - influence cancer care decisions. Methods In this patient-oriented study that included participation of 2 patient partners, qualitative data were collected from Indigenous patients with cancer and their families using an Indigenous method of sharing circles. The sharing circle occurred at a culturally appropriate place, Wanuskewin Heritage Park, Saskatoon, on Sept. 22, 2017. The first patient partner started the sharing circle by sharing their cancer journey, thus engaging the Indigenous methodology of storytelling. This patient partner was involved in selecting the data collection method and recruiting participants through snowballing and social media. Trust and world view were employed as meta themes to guide our examination of the data. In keeping with Indigenous methodology, interview transcripts were analyzed using narrative analysis. The themes were reviewed and verified by a second Indigenous patient partner. Results There were 14 participants in the sharing circle. The 2 meta themes, trust and world view, comprised 8 subthemes. The meta theme trust included mistrust with diagnosis and Western treatment after cancer therapy, protection of Indigenous medicine and physician expertise with treatment recommendations. The world view meta theme included the following subthemes: best of both worlds, spiritual beliefs, required to be strong for family and importance of knowing Indigenous survivors. Interpretation This study displayed complex relations between trust and world view in the cancer journeys of Indigenous patients and their families. These findings may assist health care providers in gaining a better understanding of how trust and world view affect the decision-making of Indigenous patients regarding cancer care.

The highly-visual nature of many social media platforms encourages appearance-related social media consciousness (ASMC), or the persistent awareness of how attractive one might look to a social media audience. The recently developed ASMC Scale, previously validated with high school-aged adolescents, provides a promising tool for systematically examining ASMC and associations with mental health symptoms. The current study examined the psychometric properties of the ASMC Scale among emerging adult men and women. Participants for Study 1 were 428 emerging adults (M age = 21.9) from five Anglophone, industrialized countries (U.S., U.K., Canada, Australia, New Zealand). Results from Study 1 indicate that the 13-item ASMC Scale has a unidimensional structure, strong internal consistency, and measurement invariance across gender and sexual orientation subgroups. Participants from Study 2 were 296 U.S. college students (M age = 18.5). Results from Study 2 demonstrated the convergent validity (i.e., associations with related offline appearance concerns and cognitions) and incremental validity (i.e., associations with depressive symptoms and disordered eating) of the ASMC Scale. Findings suggest the ASMC Scale can be reliably used to assess the extent of emerging adults’ awareness of their appearance on social media, aiding future research investigating emerging adults’ social media experiences and mental health.

Macrophages are important for effective iron recycling and erythropoiesis, but they also play a crucial role in wound healing, orchestrating tissue repair. Recently, we demonstrated a significant accumulation of iron in healing wounds and a requirement of iron for effective repair. Herein, we sought to determine the influence of iron on macrophage function in the context of wound healing. Interestingly, wound macrophages extensively sequestered iron throughout healing, associated with a prohealing M2 phenotype. In delayed healing diabetic mouse wounds, both macrophage polarization and iron sequestration were impaired. In vitro studies revealed that iron promotes differentiation, while skewing macrophages toward a hypersecretory M2-like polarization state. These macrophages produced high levels of chemokine (C-C motif) ligands 17 and 22, promoting wound reepithelialization and extracellular matrix deposition in a human ex vivo wound healing model. Together, these findings reveal a novel, unappreciated role for iron in modulating macrophage behavior to promote subsequent wound repair. These findings support therapeutic evaluation of iron use to promote wound healing in the clinic.

Chronic non-healing wounds, which primarily affect the elderly and diabetic, are a significant area of clinical unmet need. Unfortunately, current chronic wound treatments are inadequate, while available pre-clinical models poorly predict the clinical efficacy of new therapies. Here we describe a high throughput, pre-clinical model to assess multiple aspects of the human skin repair response. Partial thickness wounds were created in human ex vivo skin and cultured across a healing time course. Skin wound biopsies were collected in fixative for the whole-mount staining procedure. Fixed samples were blocked and incubated in primary antibody, with detection achieved via fluorescently conjugated secondary antibody. Wounds were counterstained and imaged via confocal microscopy before calculating percentage wound closure (re-epithelialization) in each biopsy. Applying this protocol, we reveal that 2 mm excisional wounds created in healthy donor skin are fully re-epithelialized by day 4-5 post-wounding. On the contrary, closure rates of diabetic skin wounds are significantly reduced, accompanied by perturbed barrier reformation. Combining human skin wounding with a novel whole-mount staining approach allows a rapid and reproducible method to quantify ex vivo wound repair. Collectively, this protocol provides a valuable human platform to evaluate the effectiveness of potential wound therapies, transforming pre-clinical testing and validation.

Negative pressure wound therapy is a widely used treatment for chronic, nonhealing wounds. Surprisingly, few studies have systematically evaluated the cellular and molecular effects of negative pressure treatment on human skin. In addition, no study to date has directly compared recently available single-use negative pressure modalities to traditional negative pressure devices in a controlled setting. Here we developed a novel large-scale ex vivo human skin culture system to effectively evaluate the efficacy of two different negative pressure wound therapy modalities. Single-use and traditional negative pressure devices were applied to human ex vivo wounded skin sheets cultured over a period of 48 hours. Cellular tissue response to therapy was evaluated via a combination of histological analysis and transcriptional profiling, in samples collected from the wound edge, skin adjacent to the wound, and an extended skin region. Single-use negative pressure wound therapy caused less damage to wound edge tissue than traditional application, demonstrated by improved skin barrier, reduced dermal-epidermal junction disruption and a dampened damage response. Transcriptional profiling confirmed significantly less activation of multiple pro-inflammatory markers in wound edge skin treated with single-use vs traditional negative pressure therapy. These findings may help to explain the greater efficacy of sNPWT in the clinic, while offering a noninvasive system to develop improved NPWT-based therapies.

Background and aims – Polystigma rubrum forms orange-red stromata on the surface of living leaves of Prunus spinosa and P. domestica. Records suggests that this fungus now has a much more limited distribution in Britain than recorded in the 19th and early 20th century. Methods – We studied the local distribution of the fungus in the Burren Hills of western Ireland where it remains very common. Key results – Assessment of the local distribution of the fungus over two years found stromata to occur more frequently on P. spinosa leaves in hedgerows than woodlands. On individual trees in areas of open limestone pavement, the frequency of stromata was ten times higher in 2016 than 2015, possibly related to interannual rainfall differences. On hedgerow trees subjected to winter flooding, stromata were much less abundant, whereas stromata were more abundant on leaves also infected by the gall mite Eriophyes prunispinosae. The identity of Po. rubrum was confirmed by ITS sequencing.Conclusion – At a field location where Po. rubrum stromata are present in unusually high abundance, the distribution of stromata on trees in different habitats showed high levels of variation linked to both habitat and the presence of gall mites. Further work is required to determine whether variation in leaf surface and soil moisture are the key determinants of the observed distribution. Such investigations may reveal why Po. rubrum, once common in northern Europe is now restricted mainly to westerly, coastal locations.

Characterization of cellulose nanocrystals (CNCs) is often complex and tedious. With their increased use for biological materials, polymer reinforcing agents, and other applications, better characterization methods of CNCs are needed to ensure product quality. However, because of their small size, hydrogen bonding, and low electron density, individual CNCs are difficult to image with high resolution and magnification using electron microscopy. Methods to help counter these challenges include staining for increased contrast and techniques to increase dispersion. This work tested several stains, dispersing agents, and sample supports to find a consistent method of individualizing CNCs and providing good contrast for imaging in transmission electron microscopy (TEM). The most consistent method found uses a low concentration of CNCs, bovine serum albumin as a dispersing agent, and Nanovan® as the contrasting stain on a silicon monoxide-coated Formvar TEM grid.

As cellulose nanocrystals (CNCs) are increasing in production, establishing safe workplace practices in industry will be paramount to their continued use and growth. Particles other than CNCs with similar high aspect ratios have exhibited toxicity on inhalation. Safeguards are needed to monitor concentrations of CNCs in air in industrial and laboratory settings to protect workers. However, because of their size, morphology, and chemical makeup, CNCs are difficult to characterize and differentiate from other dust and cellulose products. This work is focused on developing an effective method of characterizing the concentration of airborne ultrafine CNCs that may deposit in the respiratory tract. CNCs were tagged with rhodamine b (RhB-CNCs) for improved visualization and characterized using UV-vis spectroscopy (UV-vis), transmission electron microscopy (TEM), and dynamic light scattering (DLS), then aerosolized and collected via a novel method using plastic impingers. Concentration of RhB-CNCs was measured using UV-vis and scanning mobility particle sizer (SMPS). The plastic impinger with 3D-printed nozzle collected airborne CNCs at an efficiency that improves upon commercially available impingers for relevant particle sizes.

Effective therapeutic delivery of peptide and protein drugs is challenged by short in vivo half-lives due to rapid degradation. Sustained release formulations of αCT1, a 25 amino acid peptide drug, would afford lower dosing frequency in indications that require long term treatment, such as chronic wounds and cancers. In this study, rhodamine B (RhB) was used as a model drug to develop and optimize a double emulsion-solvent evaporation method of poly(lactic-co-glycolic acid) (PLGA) nanoparticle synthesis. Encapsulation of αCT1 in these nanoparticles (NPs) resulted in a sustained in vitro release profile over three weeks, characterized by an initial burst release of approximately 50% of total encapsulated drug over the first three days followed by sustained release over the remaining two and a half weeks. NP uptake by glioblastoma stem cells was through endocytosis and RhB and αCT1 were observed in cells after at least 4 days.

Cathode plays an important role in solid oxide fuel cell performance. This work studies the stoichiometry effect of (LaSr) x MnO 3 (LSM) cathode on its electrochemical behaviors at 800 °C by investigating the interfacial reaction of an AISI 441 interconnect/LSM electrode/yttria-stabilized zirconia (YSZ) electrolyte half-cell structure. Ohmic resistance and polarization resistance of the cathodes are analyzed by deconvoluting the electrochemical impedance spectroscopy (EIS) data. The results show that the polarization resistance is dominant for decreasing the half-cell performance. Microstructure and phase analyses show that A-site excessive LSM sample experiences stronger bonding with the YSZ electrolyte. Energy dispersive X-ray spectroscopy analyses reveal that Cr species first deposits and then is incorporated into the cathode perovskite structure by replacing Sr in the structure. Based on the above observations, the interaction mechanisms for the AISI 441 interconnect/LSM electrode/YSZ electrolyte tri-layer are proposed. Overall, the A-site deficient LSM stoichiometry is preferred for cell performance improvement.

Comparing the key determinants of health articulated by the Public Health Agency of Canada (the Agency) with the spiritual and cultural knowledge systems of First Nations peoples, as expressed by the Four Worlds International Institute for Human and Community Development (Four Worlds) and their 14 determinants of well-being and health, reveals differing philosophical perspectives. The key determinants of health can be interpreted as lacking a holistic and inclusive approach to public health services. As a result, many public health programs in Canada marginalize, ignore and suppress the needs of First Nations communities and people. Incorporating the Four Worlds guiding principles and its 14 health determinants model within the context of Canadian public health services geared towards First Nations populations provides the opportunity to develop a deeper understanding of social determinants of health. Therefore, when implementing public health initiatives to address the health status of First Nations people in Canada, it is important that the Agency incorporate the guiding principles of the Four Worlds: Development Comes from Within; No Vision, No Development; Individual and Community Transformations Must Go Hand in Hand; and Holistic Learning is the Key to Deep and Lasting Change. Reconceptualizing the key determinants of health to encompass the worldview expressed by the Four Worlds acknowledges the cultural wisdom of First Nations people and offers the potential to develop more inclusive public health services.

While there is often great enthusiasm for volunteering in prison and jail education and literacy programs, those interested rarely give thought to the kinds of primary and secondary trauma that result from such work. Yet compassion fatigue is all too real for volunteer writing teachers who encounter difficult disclosures of violence, rape, and loss week after week. Interviews with volunteers revealed anxiety about performance, frustration with the justice system, awareness of privilege, and longing for communities of support. This chapter explores volunteers’ understanding of the impact of their work in one literacy program and offers narrative and writing therapy techniques as appropriate and needed methods for volunteers coping with the burden of cumulative stories of trauma disclosed by incarcerated writers.

Results from an experiment with two parts are presented in this paper. In part one, participants listened to sentences containing two, three, four, or five clauses, and were asked questions about the content of the sentences. The results of part one demonstrate that an important unit of representation in sentence memory is the clause, and not some other component of discourse structure. In part two, the same group of participants performed eight different short-term storage/working memory tasks. A composite complex span score was computed for each participant based on three working memory tasks closely based on Daneman & Carpenter's (1980) reading span task. This working memory measure was significantly correlated with the participants' performance on the sentence memory task in part one. A second working memory measure—N-back—was also significantly correlated with the participants' performance on the sentence memory task, and there was no correlation between their performance on the complex span task and the N-back task. It is therefore concluded that (i) working memory consists of a number of dissociable components; and (ii) memory for sentences taps into more than one of these working memory components. Furthermore, the high correlations of sentence memory with the complex span and the N-back tasks (neither of which are language processing tasks) suggests that memory for sentences is not simply a result of linguistic experience; rather, it is likely that an independent working memory component contributes to participants' performance on the sentence memory task.

We present the European project TeleSCoPE - Telehealth Services Code of Practice for Europe. It is developing a comprehensive Code of Practice that relates to those aspects of telemedicine and telecare that are delivered in peoplećs homes and mediated through ICT. This is a 3-year project (2010-2013) co-financed by the European Executive Agency for Health and Consumers. Among 13 project partners from 7 countries, two are from Slovenia. The main output of the TeleSCoPE project will be the Code itself and associated plans to facilitate its adoption by the EU member states. Among its side products is the glossary of terms in telehealth, which was used as a key document when preparing a foundation document for a national strategy on telehealth in Slovenia.

Results from an experiment with two parts are presented in this paper. In part one, participants listened to sentences containing two, three, four, or five clauses, and were asked questions about the content of the sentences. The results of part one demonstrate that an important unit of representation in sentence memory is the clause, and not some other component of discourse structure. In part two, the same group of participants performed eight different short-term storage/working memory tasks. A composite complex span score was computed for each participant based on three working memory tasks closely based on DanemanCarpenter's (1980) reading span task. This working memory measure was significantly correlated with the participants' performance on the sentence memory task in part one. A second working memory measure--N-back--was also significantly correlated with the participants' performance on the sentence memory task, and there was no correlation between their performance on the complex span task and the N-back task. It is therefore concluded that (i) working memory consists of a number of dissociable components; and (ii) memory for sentences taps into more than one of these working memory components. Furthermore, the high correlations of sentence memory with the complex span and the N-back tasks (neither of which are language processing tasks) suggests that memory for sentences is not simply a result of linguistic experience; rather, it is likely that an independent working memory component contributes to participants' performance on the sentence memory task.

To test the null hypotheses that there is no significant difference between the performance and adjustment of student teachers who have a university supervisor and those who do not, ninety-six student teachers were divided into two groups: control, (those with a university supervisor) and experimental (those without a university supervisor). To measure performance, the Purdue Teacher Evaluation Scale was administered to cooperating teachers, student teachers, and secondary students of both groups. The Lindquist Type I analysis of variance was used to analyze test results. To measure adjustment, the Purdue Student-Teacher Opinionaire was administered to student teachers of both groups. T-tests were used to analyze test results. The test results supported both of the null hypotheses.