For many types of learning, spaced training, which involves repeated long inter-trial intervals, leads to more robust memory formation than does massed training, which involves short or no intervals. ...Several cognitive theories have been proposed to explain this superiority, but only recently have data begun to delineate the underlying cellular and molecular mechanisms of spaced training, and we review these theories and data here. Computational models of the implicated signalling cascades have predicted that spaced training with irregular inter-trial intervals can enhance learning. This strategy of using models to predict optimal spaced training protocols, combined with pharmacotherapy, suggests novel ways to rescue impaired synaptic plasticity and learning.
Decades of research on the cellular mechanisms of memory have led to the widely held view that memories are stored as modifications of synaptic strength. These changes involve presynaptic processes, ...such as direct modulation of the release machinery, or postsynaptic processes, such as modulation of receptor properties. Parallel studies have revealed that memories might also be stored by nonsynaptic processes, such as modulation of voltage-dependent membrane conductances, which are expressed as changes in neuronal excitability. Although in some cases nonsynaptic changes can function as part of the engram itself, they might also serve as mechanisms through which a neural circuit is set to a permissive state to facilitate synaptic modifications that are necessary for memory storage.
Photo-excitation of certain semiconductors can lead to the production of reactive oxygen species that can inactivate microorganisms. The mechanisms involved are reviewed, along with two important ...applications. The first is the use of photocatalysis to enhance the solar disinfection of water. It is estimated that 750 million people do not have accessed to an improved source for drinking and many more rely on sources that are not safe. If one can utilize photocatalysis to enhance the solar disinfection of water and provide an inexpensive, simple method of water disinfection, then it could help reduce the risk of waterborne disease. The second application is the use of photocatalytic coatings to combat healthcare associated infections. Two challenges are considered, i.e., the use of photocatalytic coatings to give "self-disinfecting" surfaces to reduce the risk of transmission of infection via environmental surfaces, and the use of photocatalytic coatings for the decontamination and disinfection of medical devices. In the final section, the development of novel photocatalytic materials for use in disinfection applications is reviewed, taking account of materials, developed for other photocatalytic applications, but which may be transferable for disinfection purposes.
The coronavirus disease 2019 (COVID-19) pandemic poses a challenge to the physical and mental well-being of doctors worldwide. Countries around the world introduced severe social restrictions, and ...significant changes to health service provision in the first wave of the pandemic to suppress the spread of the virus and prioritize healthcare for those who contracted it. This study interviewed 48 hospital doctors who worked in Ireland during the first wave of the pandemic and investigated their conceptualizations of their own well-being during that time (March-May 2020). Doctors were interviewed via Zoom™ or telephone. Interview transcripts were analyzed using structured thematic analysis. Five composite narratives are presented which have been crafted to illustrate themes and experiences emerging from the data. This study found that despite the risks of contracting COVID-19, many doctors saw some improvements to their physical well-being in the first wave of the pandemic. However, most also experienced a decline in their mental well-being due to anxiety, emotional exhaustion, guilt, isolation and poor support. These findings shed light on doctor well-being during COVID-19, and the ways in which they have been affected by the pandemic, both professionally and personally. The paper concludes by highlighting how doctors' work life and well-being can be better supported during and after the COVID-19 pandemic.
In recent years, the area of developing visible-light-active photocatalysts based on titanium dioxide has been enormously investigated due to its wide range of applications in energy and environment ...related fields. Various strategies have been designed to efficiently utilize the solar radiation and to enhance the efficiency of photocatalytic processes. Building on the fundamental strategies to improve the visible light activity of TiO2-based photocatalysts, this Perspective aims to give an insight into many contemporary developments in the field of visible-light-active photocatalysis. Various examples of advanced TiO2 composites have been discussed in relation to their visible light induced photoconversion efficiency, dynamics of electron–hole separation, and decomposition of organic and inorganic pollutants, which suggest the critical need for further development of these types of materials for energy conversion and environmental remediation purposes.
Energy justice is now an established research topic in the field of energy policy. Despite the growing popularity of energy justice research, however, conceptual and analytical frameworks used in the ...field have remained limited. This paper reviews the prevailing three-tenet framework of energy justice which has shaped the current discourse based on the three dimensions—distributional, procedural, and recognition justice. As an effort to contribute to expanding the research agenda of energy justice problems, we propose a new understanding of the production of energy injustice by characterizing three institutionalized tendencies of dominant modern energy systems: (1) preference for large-scale technical systems and distancing of system designs from local decision-making processes, (2) centralization of energy production and concomitant distancing of supply from users, and (3) widespread ‘risk-taking’ tendencies portrayed by designers and proponents of current energy supply systems as a necessary ‘price to pay’ for technological innovation and social progress. We then connect these three tendencies to political, economic, and technical ideologies of modernism that often provide justifications for energy inequity: (1) top-down political and economic decision-making systems, (2) technical interpretation of sustainability, (3) specialist understanding of fairness, and (4) path dependency in the modern energy paradigm. Finally, we present an illustration of how this new conception of systemic energy injustice can be applied in practice using the case of South Korea's nuclear power system and Seoul's One Less Nuclear Power Plant Initiative.
With memory encoding reliant on persistent changes in the properties of synapses, a key question is how can memories be maintained from days to months or a lifetime given molecular turnover? It is ...likely that positive feedback loops are necessary to persistently maintain the strength of synapses that participate in encoding. Such feedback may occur within signal-transduction cascades and/or the regulation of translation, and it may occur within specific subcellular compartments or within neuronal networks. Not surprisingly, numerous positive feedback loops have been proposed. Some posited loops operate at the level of biochemical signal-transduction cascades, such as persistent activation of Casuperscript 2+/calmodulin kinase II (CaMKII) or protein kinase M?. Another level consists of feedback loops involving transcriptional, epigenetic and translational pathways, and autocrine actions of growth factors such as BDNF. Finally, at the neuronal network level, recurrent reactivation of cell assemblies encoding memories is likely to be essential for late maintenance of memory. These levels are not isolated, but linked by shared components of feedback loops. Here, we review characteristics of some commonly discussed feedback loops proposed to underlie the maintenance of memory and long-term synaptic plasticity, assess evidence for and against their necessity, and suggest experiments that could further delineate the dynamics of these feedback loops. We also discuss crosstalk between proposed loops, and ways in which such interaction can facilitate the rapidity and robustness of memory formation and storage.
Pulmonary embolectomy is often indicated for central pulmonary embolism (PE) with hemodynamic instability, but remains controversial for hemodynamically stable patients with signs of right ...ventricular dysfunction. Because thrombolytic therapy is often contraindicated postoperatively, we reviewed risk factors and outcomes of pulmonary embolectomy for stable and unstable central PE, particularly in the early postoperative period.
Between October 1999 and September 2013, 115 patients underwent pulmonary embolectomy for central, hemodynamically unstable PE (49 of 115, 43%) or hemodynamically stable PE (56 of 115, 49%). Ten operations for alternate indications (right atrial mass, endocarditis) were excluded for comparison analysis, leaving 105 patients.
Mean age was 59 ± 13 years; 46 of 105 patients (44%) had recent surgery (within 5 weeks): orthopedic (12 of 46, 25%), neurosurgery (11 of 46, 24%), or general surgery (10 of 46, 22%). Preoperative demographics did not differ between groups, except for the frequency of cardiopulmonary resuscitation among unstable patients (11 of 49, 22%) versus stable patients (0 of 56, 0%; p < 0.001). Operative mortality for the combined groups was 6.6% (7 of 105): unstable 10.2% (5 of 49) versus stable 3.6% (2 of 56; p = 0.247). Of 11 patients requiring preoperative cardiopulmonary resuscitation, 4 died. Six-month, 1-year, and 3-year survival rates were, respectively, 75%, 68.4%, and 65.8% for unstable PE, and 92.6%, 86.7%, and 80.4% for stable PE (p = 0.018).
This large series of pulmonary embolectomies demonstrates excellent early and late survival rates for patients with stable PE and unstable PE. These findings confirm pulmonary embolectomy as a beneficial therapeutic option for central PE, especially during the postoperative period when thrombolytic therapy is often contraindicated.
•Healthcare worker (HCW) mental well-being is a core aspect of workforce capacity.•COVID-19 increased work-life stressors for HCW negatively affecting their mental wellbeing.•Addressing HCW mental ...wellbeing requires an integrated package of psychosocial support services.•Structural factors determining working conditions for HCW influence the support-package's effectiveness.
Healthcare worker (HCW) mental well-being has become a global public health priority as health systems seek to strengthen their resilience in the face of the COVID-19 pandemic. Analysing data from the Health System Response Monitor, we present six case studies (Denmark, Italy, Kyrgyzstan, Lithuania, Romania, and the United Kingdom) as a comparative review of policy interventions supporting HCW mental health during the pandemic. The results illustrate a wide range of interventions. While Denmark and the United Kingdom built on pre-existing structures to support HCW mental wellbeing during the pandemic, the other countries required new interventions. Across all cases, there was a reliance on self-care resources, online training tools, and remote professional support.
Based on our analysis, we develop four policy recommendations for the future of HCW mental health supports. First, HCW mental health should be seen as a core facet of health workforce capacity. Second, effective mental health supports requires an integrated psychosocial approach that acknowledges the importance of harm prevention strategies and organisational resources (psychological first aid) alongside targeted professional interventions. Third, personal, professional and practical obstacles to take-up of mental health supports should be addressed. Fourth, any specific support or intervention targeting HCW's mental health is connected to, and dependent on, wider structural and employment factors (e.g. system resourcing and organisation) that determine the working conditions of HCWs.
PDF
