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Human epidemiological and animal-model studies suggest that separate exposure to stress or serotonin-selective reuptake inhibitor (SSRI) antidepressants during pregnancy increases risks for neurodevelopmental disorders in offspring. Yet, little is known about the combined effects of maternal stress and SSRIs with regard to brain development in utero. We found that the placenta is highly permeable to the commonly prescribed SSRI (±)-citalopram (CIT) in humans and mice, allowing rapid exposure of the fetal brain to this drug. We investigated the effects of maternal chronic unpredictable stress in mice with or without maternal oral administration of CIT from embryonic day (E)8 to E17. We assessed fetal brain development using magnetic resonance imaging and quantified changes in serotonergic, thalamocortical, and cortical development. In utero exposure to maternal stress did not affect overall fetal brain growth. However, serotonin tissue content in the fetal forebrain was increased in association with maternal stress; this increase was reversed by maternal CIT. In utero exposure to stress increased the numbers of deep-layer neurons in specific cortical regions, whereas CIT increased overall cell numbers without changing the proportions of layer-specific neurons to offset the effects of stress on deep-layer cortical development. These findings suggest that stress and SSRI exposure in utero differentially impact serotonin-dependent fetal neurodevelopment such that CIT reverses key effects of maternal gestational stress on offspring brain development.

Natural analogues are systems that have evolved over geological timescales with features similar to one or several components of a deep geological repository (DGR). Natural analogues complement short-duration laboratory studies since they are existing reflections of many long-term processes that might affect the performance of a repository. Mathematical models are often used for the post-closure safety assessment of a DGR. Confidence in the models' predictions is enhanced when the models successfully simulate the past evolution of a natural analogue. This paper summarizes the Canadian Nuclear Safety Commission's (CNSC's) recent research on natural analogues to inform on (1) glacial erosion, (2) engineered barrier system, and (3) uranium reactive transport in the context of DGRs for radioactive wastes. Glaciation and its erosion are prominent factors impacting the performance of future DGRs at high latitudes in the northern hemisphere. The authors have reviewed the field data from the Greenland Analogue Project, developed a conceptual and mathematical model for the simulation of the thermal conditions within the Greenland ice sheet, as well as the thermal-hydraulic conditions at its base and the ice sheet velocity, and eventually estimated the erosion rate at the site. The Cigar Lake Analogue demonstrates the long-term radionuclide containment capability of the illite clay zone enveloping the ore body, serving as an analogy to the engineered clay barriers. The CNSC and University of Ottawa analyzed 129I in the Cigar Lake core samples, and modeled and correlated the diffusion-dominated transport of radionuclides over the geological evolution of the Cigar Lake deposit. The results provide information on the mobility of fission products and significant radionuclides in conditions analogous to the source, engineered barriers, and near-field host rock of a DGR. The reactive transport and geochemistry of the Kiggavik-Andrew Lake uranium deposit mineralization and remobilization was another natural uranium deposit analogue studied by the CNSC. A reactive transport model was established according to the conceptualized geochemical processes and run under specified boundary and initial conditions to validate the geochemical processes. The geometry, timing, geochemistry, and fluid composition were used as model constraints. [ABSTRACT FROM AUTHOR]

Purpose: Considerable research has shown adverse neurobiological effects of chronic alcohol use, including long-term and potentially permanent changes in the structure and function of the brain; however, much less is known about the neurobiological consequences of chronic smoking, as it has largely been ignored until recently. In this article, we present a conceptual model proposing the effects of smoking on neurocognition and the role that physical activity may play in this relationship as well as its role in smoking cessation. Methods: Pertinent published peer-reviewed articles deposited in PubMed delineating the pathways in the proposed model were reviewed. Results: The proposed model, which is supported by emerging research, demonstrates a bidirectional relationship between smoking and executive functioning. In support of our conceptual model, physical activity may moderate this relationship and indirectly influence smoking behavior through physical activity-induced changes in executive functioning. Conclusions: Our model may have implications for aiding smoking cessation efforts through the promotion of physical activity as a mechanism for preventing smoking-induced deficits in neurocognition and executive function.

Analysis of 10 worker education programs indicated that their responses to globalization ranged from accommodation to transformative learning. There was no consensus on whose interests were served by globalization. Some programs promoted international solidarity, which can challenge the dominance of neoliberalism. The disunified provision of worker education hampers this effort. (SK)

The coronavirus disease 2019 pandemic caused an unprecedented surge of patients presenting to emergency departments and forced hospitals to adapt to provide care to patients safely and effectively. The purpose here was to disseminate a novel program developed under disaster conditions to address advance care planning communications. A program development and initial evaluation was conducted for the Remote Goals of Care program, which was created for families to communicate patient goals of care and reduce responsibilities of those in the emergency department. This program facilitated 64 remote goals of care conversation, with 72% of conversations taking place remotely with families of patients who were unable to participate. These conversations included discussions of patient preferences for care, including code status, presence of caregivers or surrogates, understanding of diagnosis and prognosis, and hospice care. Initially, this program was available 24 hours per day, 7 days per week, with gradual reduction in hours as needs shifted. Seven nurses who were unable to work in corona-positive environments but were able to continue working remotely were utilized. Lessons learned include the need for speed and agility of response and the benefit of established relationships between traditionally siloed specialties. Additional considerations include available technology for patients and families and expanding the documentation abilities for remote nurses. A logic model was developed to support potential program replication at other sites. Upon initial evaluation, Remote Goals of Care Program was well received and demonstrated promise in decanting the responsibility of goals of care discussions from the emergency department to a calmer, remote setting. In future iterations, additional services and technology adjustments can be made to make this program more accessible to more patients and families. Other facilities may wish to replicate our Remote Goals of Care Program described here. [ABSTRACT FROM AUTHOR]

The issue of integrating technology into adult literacy programs would benefit from the implementation of a curriculum deliberation process that includes perspectives of practitioners, learners, subject matter experts, and milieus. This would ensure the development of coherent curricula, with the key consideration being the efficacy of computers in terms of educational outcomes. (SK)

In this study we investigate relationships between the nanoscale structure of collagen fibrils and the macroscale functional response of collagenous tissues. To do so, we study two functionally distinct classes of tendons, positional tendons and energy storing tendons, using a bovine forelimb model. Molecular-level assessment using differential scanning calorimetry (DSC), functional crosslink assessment using hydrothermal isometric tension (HIT) analysis, and ultrastructural assessment using scanning electron microscopy (SEM) were used to study undamaged, ruptured, and cyclically loaded samples from the two tendon types. HIT indicated differences in both crosslink type and crosslink density, with flexor tendons having more thermally stable crosslinks than the extensor tendons (higher T Fmax of >90 vs. 75.1 ± 2.7 °C), and greater total crosslink density than the extensor tendons (higher t 1/2 of 11.5 ± 1.9 vs. 3.5 ± 1.0 h after NaBH 4 treatment). Despite having a lower crosslink density than flexor tendons, extensor tendons were significantly stronger (37.6 ± 8.1 vs. 23.1 ± 7.7 MPa) and tougher (14.3 ± 3.6 vs. 6.8 ± 3.4 MJ/m 3 ). SEM showed that collagen fibrils in the tougher, stronger extensor tendons were able to undergo remarkable levels of plastic deformation in the form of discrete plasticity, while those in the flexor tendons were not able to plastically deform. When cyclically loaded, collagen fibrils in extensor tendons accumulated fatigue damage rapidly in the form of kink bands, while those in flexor tendons did not accumulate significant fatigue damage. The results demonstrate that collagen fibrils in functionally distinct tendons respond differently to mechanical loading, and suggests that fibrillar collagens may be subject to a strength vs. fatigue resistance tradeoff. Statement of Significance Collagen fibrils—nanoscale biological cables—are the fundamental load-bearing elements of all structural human tissues. While all collagen fibrils share common features, such as being composed of a precise quarter-staggered polymeric arrangement of triple-helical collagen molecules, their structure can vary significantly between tissue types, and even between different anatomical structures of the same tissue type. To understand normal function, homeostasis, and disease of collagenous tissues requires detailed knowledge of collagen fibril structure-function. Using anatomically proximate but structurally distinct tendons, we show that collagen fibrils in functionally distinct tendons have differing susceptibilities to damage under both tensile overload and cyclic fatigue loading. Our results suggest that the structure of collagen fibrils may lead to a strength versus fatigue resistance tradeoff, where high strength is gained at the expense of fatigue resistance, and vice versa. [ABSTRACT FROM AUTHOR]

Suction devices have widespread uses in the clinical environment. The process of suction is the removal of fluid or other debris using a vacuum, and the properties of suction devices are governed by the physics of the flow of fluid through a tube. The rate of flow is dependent on the radius, length and pressure difference across the ends of the tube. A pump is used to create the vacuum, the efficiency of which depends on the maximum displacement and degree of sub-atmospheric pressure that is generated. A high-efficiency, high-pressure system is used for the removal of vomit and secretions from the airway; a low-pressure system is used for intercostal drains. A central electrically driven pump is utilized in most clinical areas, but portable systems are available. The main components of a suction device are the pump, control box, reservoir, transfer tubing and suction catheter. Safety features prevent contamination of the pump and atmosphere by waste particles. Adverse effects of airway suction by rigid or flexible catheters include soft tissue trauma and airway obstruction as well as hypoxaemia, atelectasis and cardiovascular instability. [ABSTRACT FROM AUTHOR]

This paper studies workers’ resistance to the spread of informal and flexible employment patterns in Greece during the ongoing economic crisis. It focuses upon the spatial aspects of two strikes, the first by immigrant agricultural workers employed in the strawberry fields of Nea Manolada, in the Peloponnesus region, and the second by steelworkers employed at the Hellenic Steelworks SA in Aspropyrgos, in the Attica region. The paper analyses workers’ agency in both these cases, viewing it as a relational phenomenon strongly determined by the economic specificities of the sector to which workers’ employers belonged, by the workers’ ability (or not) to develop trans-local networks of solidarity and by the timing of the two struggles. We view the paper as a contribution to the growing body of Labour Geography research in two ways: (i) it speaks to how to theorise worker agency in a more nuanced manner; and (ii) it argues that, rather than viewing workers as simply social actors who are caught up in labour markets that are assumed to be structured by the actions of capital and the state (as per much economic theory), workers can actually play important roles in shaping how labour markets function and in resisting the tendency for precarious employment relations to spread across them. [ABSTRACT FROM AUTHOR]

Background Right ventricular (RV) failure is a major cause of morbidity and mortality after left ventricular assist device (LVAD) implantation. Whether RV function deteriorates with prolonged LVAD support is unknown. Speckle-tracking echocardiography provides a sensitive, noninvasive, reproducible, and quantitative assessment of RV systolic and diastolic function. Methods Echocardiograms were retrospectively reviewed from before and after implantation of a Heartmate II LVAD. Speckle-tracking analysis was performed to measure RV longitudinal systolic strain, strain rate, and diastolic strain rate for each patient at baseline and over discrete time periods after LVAD implantation. Results Seventeen patients were included in the analysis, with an average follow-up after LVAD implantation of 234 ± 125 days. RV systolic strain improved in 15 patients, decreasing from -7.4 ± 2.3% to -9.7 ± 3.3% after LVAD (P = .026). Systolic strain rate improved in 11 patients, decreasing from -0.67 ± 0.25%/s to -0.96 ± 0.36%/s (P = .011). RV diastolic strain rate improved in 12 patients, increasing from 0.70 ± 0.33%/s to 1.02 ± 0.40%/s (P = .016). Conclusions Chronic LVAD support improves RV systolic and diastolic function in LVAD patients who did not require an RV assist device. Speckle-tracking echocardiography may offer a noninvasive technique for identifying and monitoring improvements in RV function in LVAD patients. [ABSTRACT FROM AUTHOR]