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Salt related weathering of stones has been attributed to pressures exerted by repeated cycles of crystallization within pores. Relative Humidity (RH) is a key driver for dissolution and crystallization processes. Despite the prevalence of salt mixtures in natural environments, most experimental work has focused on single salts. Thus, the identification of salt mixture composition and their behavior is necessary to understand weathering. Thermodynamic calculations are used to analyze several thousand realistic salt mixtures found in weathered stone. We identify two common mixture types and their behavior. From at least 85 salt species theoretically present, 14 common salts are identified that occur most frequently and their critical RH points are discussed. These findings have wide-reaching implications for understanding salt weathering processes and informing the design of experimental stone weathering research.

Damage to porous materials in heritage buildings caused by salt mixture crystallization is driven by the surrounding environmental conditions. To understand the crystallization behavior of a mixed salt solution as a function of changing climatic conditions (i.e., relative humidity and temperature), excluding factors such as the internal pore structure, the thermodynamic model ECOS/RUNSALT is the only freeware available that requires simple input and includes the most relevant ions for heritage buildings and solids. We suggest the use of specific terminology and describe how to use the model and how to interpret the output, with emphasis on key limitations for which solutions are provided. When used correctly, the model output can be trusted, specifically when it is used to inform preventive conservation (e.g., environmental conditions in which salt crystallization cycles should not occur). However, salt mixture kinetics and the internal pore structure remain crucial parameters that are not considered in the model. These aspects need further attention to develop a better understanding and correctly model salt damage in relation to climatic changes.

Understanding salt mixtures in the built environment is crucial to evaluate damage phenomena. This contribution presents charge balance calculations applied to a dataset of 11412 samples taken from 338 sites, building materials showing signs of salt deterioration. Each sample includes ion concentrations of Na+, K+, Mg2+, Ca2+, Cl−, NO3−, and SO42− adjusted to reach charge balance for data evaluation. The calculation procedure follows two distinct pathways: i) an equal adjustment of all ions, ii) adjustments to the cations in sequence related to the solubility of the theoretical solids. The procedure applied to the dataset illustrates the quantification of salt mixture compositions and highlights the extent of adjustments applied in relation to the sample mass to aid interpretation. The data analysis allows the identification of theoretical carbonates that could influence the mixture behavior. Applying the charge balance calculations to the dataset validated common ions found in the built environment and the identification of three typical mixture compositions. Additionally, the data can be used as direct input for thermodynamic modeling.

Fear extinction underlies prolonged exposure, one of the most well-studied treatments for posttraumatic stress disorder (PTSD). There has been increased interest in exploring pharmacological agents to enhance fear extinction learning in humans and their potential as adjuncts to PE. The objective of such adjuncts is to augment the clinical impact of PE on the durability and magnitude of symptom reduction. In this study, we examined whether hydrocortisone (HC), a corticosteroid, and D-Cycloserine (DCS), an N-methyl-D-aspartate receptor partial agonist, enhance fear extinction learning and consolidation in individuals with PTSD. In a double-blind placebo-controlled 3-group experimental design, 90 individuals with full or subsyndromal PTSD underwent fear conditioning with stimuli that were paired (CS+) or unpaired (CS-) with shock. Extinction learning occurred 72 h later and extinction retention was tested one week after extinction. HC 25 mg, DCS 50 mg or placebo was administered one hour prior to extinction learning. During extinction learning, the DCS and HC groups showed a reduced differential CS+/CS- skin conductance response (SCR) compared to placebo (b = -0.19, CI = -0.01 to -37, p = 0.042 and b = -0.25, CI = -08 to -0.43, p = 0.005, respectively). A nonsignificant trend for a lower differential CS+/CS- SCR in the DCS group, compared to placebo, (b = -0.25, CI = 0.04 to -0.55, p = 0.089) was observed at retention testing, one week later. A single dose of HC and DCS facilitated fear extinction learning in participants with PTSD symptoms. While clinical implications have yet to be determined, our findings suggest that glucocorticoids and NMDA agonists hold promise for facilitating extinction learning in PTSD.

Multi-label Text Classification (MLTC) is the task of categorizing documents into one or more topics. Considering the large volumes of data and varying domains of such tasks, fully supervised learning requires manually fully annotated datasets which is costly and time-consuming. In this paper, we propose BERT-Flow-VAE (BFV), a Weakly-Supervised Multi-Label Text Classification (WSMLTC) model that reduces the need for full supervision. This new model (1) produces BERT sentence embeddings and calibrates them using a flow model, (2) generates an initial topic-document matrix by averaging results of a seeded sparse topic model and a textual entailment model which only require surface name of topics and 4-6 seed words per topic, and (3) adopts a VAE framework to reconstruct the embeddings under the guidance of the topic-document matrix. Finally, (4) it uses the means produced by the encoder model in the VAE architecture as predictions for MLTC. Experimental results on 6 multi-label datasets show that BFV can substantially outperform other baseline WSMLTC models in key metrics and achieve approximately 84% performance of a fully-supervised model., Comment: 8 pages, 4 figures

Collaboration between the two Joint Programming Initiatives “Cultural Heritage and Global Change” (JPI CH), and “Connecting Climate Knowledge for Europe” (JPI Climate) began in 2019 and led to the organisation of a joint workshop a year later. Following the recommendations in the workshop report, an expert working group was set up to scope research gaps and opportunities at the interface of cultural heritage and climate change, culminating in the publication of this White Paper. This strategic document is expected to support the two JPIs to generate policy-relevant research outcomes.

Climate change poses a threat to heritage globally. Decolonial approaches to climate change–heritage research and practice can begin to address systemic inequities, recognize the breadth of heritage and strengthen adaptation action globally., Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public., Architecture and the Built Environment, History, Form & Aesthetics

Salt weathering is one of the most important causes of deterioration in the built environment. Two crucial aspects need further investigation to understand the processes and find suitable measures: the impact of different climatic environments and the properties of salt mixture crystallization. We demonstrate the importance of kinetics in quantifying crystallization and dissolution cycles by combining droplet and capillary laboratory experiments with climate data analysis. The results proved that dissolution times for pure NaCl are typically slower than crystallization, while thermodynamic modelling showed a lower RHeq of NaCl (65.5%) in a salt mixture (commonly found in the built heritage) compared to its RHeq as a single salt (75.5%). Following the results, a minimum time of 30 min is considered for dissolution and the two main RHeq thresholds could be applied to climate data analysis. The predicted number of dissolution/crystallization cycles was significantly dependent on the measurement frequency (or equivalent averaging period) of the climatic data. An analysis of corresponding rural and urban climate demonstrated the impact of spatial phenomena (such as the urban heat island) on the predicted frequency cycles. The findings are fundamental to improve appropriate timescale windows that can be applied to climate data and to illustrate a methodology to quantify salt crystallization cycles in realistic environments as a risk assessment procedure. The results are the basis for future work to improve the accuracy of salt risk assessment by including the kinetics of salt mixtures. [Figure not available: see fulltext.]

Research focusing on climate change and cultural heritage informs heritage management and policy. Fatorić and Seekamp assessed this field up to 2015, highlighting the need for periodic reassessment of the field given the observed growth and research that documents how cultural heritage contributes to climate change mitigation and adaptation. Five years on, this systematic review reflects on the state of the art by evaluating 165 publications (2016–2020) about cultural heritage and climate change. We find the field continues to grow, and remains rich in disciplinary and methodological diversity, but predominantly represents research in and about Europe. The number of publications about integrating cultural heritage into adaptation and mitigation are increasing but remain relatively few compared to those about physical impacts on individual buildings or sites. The impact of climate change on intangible heritage has rarely been the sole focus of recent research. Although researchers are increasingly situating their research in a wider context of opportunities and barriers, vague timescales, and unspecific references to changes in the natural environment are additional limitations. This review also identified a lack of international collaboration, highlighting the urgent need for global cooperation and knowledge exchange on climate change and cultural heritage., History & Complexity

Research focusing on climate change and cultural heritage informs heritage management and policy. Fatorić and Seekamp assessed this field up to 2015, highlighting the need for periodic reassessment of the field given the observed growth and research that documents how cultural heritage contributes to climate change mitigation and adaptation. Five years on, this systematic review reflects on the state of the art by evaluating 165 publications (2016–2020) about cultural heritage and climate change. We find the field continues to grow, and remains rich in disciplinary and methodological diversity, but predominantly represents research in and about Europe. The number of publications about integrating cultural heritage into adaptation and mitigation are increasing but remain relatively few compared to those about physical impacts on individual buildings or sites. The impact of climate change on intangible heritage has rarely been the sole focus of recent research. Although researchers are increasingly situating their research in a wider context of opportunities and barriers, vague timescales, and unspecific references to changes in the natural environment are additional limitations. This review also identified a lack of international collaboration, highlighting the urgent need for global cooperation and knowledge exchange on climate change and cultural heritage., History, Form & Aesthetics

BACKGROUND: The role of hippocampus in context-dependent recall of extinction is well recognized. However, little is known about how intervention-induced changes in hippocampal networks relate to improvements in extinction learning. In this study, we hypothesized that mindfulness training creates an optimal exposure condition by heightening attention and awareness of present moment sensory experience, leading to enhanced extinction learning, improved emotion regulation, and reduced anxiety symptoms. METHODS: We tested this hypothesis in a randomized controlled longitudinal study design using a 2-day fear conditioning and extinction protocol. The mindfulness training group included 42 participants (28 women) and the control group included 25 participants (15 women). RESULTS: We show that mindfulness training is associated with differential engagement of the right supramarginal gyrus as well as hippocampal-cortical reorganization. We also report enhanced hippocampal connectivity to the primary sensory cortex during retrieval of extinguished stimuli following mindfulness training. CONCLUSIONS: These findings suggest hippocampal-dependent changes in contextual retrieval as one plausible neural mechanism through which mindfulness-based interventions enhance fear extinction and foster stress resilience.

Recent conflicts have directed much academic and media attention to special operations forces (SOF). Despite the attention, the application of SOF in asymmetric conventional warfare or irregular conflict has not been fully examined in the context of just war theory. In addition, SOF have often been portrayed superficially, painting them as indiscriminate or unscrupulous warriors. This thesis argues to the contrary, that the application of SOF represents an evolution of just war theory in an era of increasingly irregular conflict. This thesis expands just war thinking to activities short of armed conflict. It contends that SOF constitute a unique extension of the ethical principles that morally bind military capabilities under just war theory. Moreover, this thesis examines the moral utility of SOF operations as a means of preventing unnecessary loss of life prior to, during, and in the wake of armed conflict. SOF can function, in both theory and practice, as a distinct moral improvement over most other forms of irregular or indirect conflict, across nearly all phases of conflict. These conclusions aim to provide insight to planners, observers, and policy-makers who seek to understand and efficiently respond to emergent or persistent challenges to global stability and national security., http://archive.org/details/justwartheoryrel1094559564, Major, United States Army, Approved for public release; distribution is unlimited.

Recent conflicts have directed much academic and media attention to special operations forces (SOF). Despite the attention, the application of SOF in asymmetric conventional warfare or irregular conflict has not been fully examined in the context of just war theory. In addition, SOF have often been portrayed superficially, painting them as indiscriminate or unscrupulous warriors. This thesis argues to the contrary, that the application of SOF represents an evolution of just war theory in an era of increasingly irregular conflict. This thesis expands just war thinking to activities short of armed conflict. It contends that SOF constitute a unique extension of the ethical principles that morally bind military capabilities under just war theory. Moreover, this thesis examines the moral utility of SOF operations as a means of preventing unnecessary loss of life prior to, during, and in the wake of armed conflict. SOF can function, in both theory and practice, as a distinct moral improvement over most other forms of irregular or indirect conflict, across nearly all phases of conflict. These conclusions aim to provide insight to planners, observers, and policy-makers who seek to understand and efficiently respond to emergent or persistent challenges to global stability and national security.

Research Question: Does the application of SOF represent a moral improvement in the prevention of unnecessary loss of life prior to, during, and post-armed conflict scenarios? Further, does SOF represent an evolution, as well as, an ethical expansion in military capability bound by just war theory?

Animal research suggests that reactivation (retrieval) of a consolidated memory can return it to a labile state from which it must be restabilized in order to persist. This stabilization process has been termed reconsolidation , and various behavioral and pharmacological interventions have been found to modify or block it. The aim of this project is to create an experimental assay in the form of an optimal Pavlovian differential fear-conditioning paradigm, within which the relative strengths of various pharmacological and behavioral, reconsolidation-blocking interventions can be tested. Thus far, we have completed data collection for two groups: pharmacological, i.e., propranolol, and behavioral, i.e., delayed extinction. Data from the propranolol group demonstrate that participants show differential conditioning learning on Day 1, supporting the validity of our modified fear-conditioning paradigm. However, propranolol administration at the time of memory reactivation failed to decrease the fear memory, as indexed by skin conductance. These findings are communicated in a manuscript (attached), which will be submitted for publication to Psychophysiology later this month. Data from the behavioral group are presently being analyzed and prepared for publication. We are presently recruiting participants to receive a new candidate pharmacological intervention, mifepristone (RU-486), within the same fear-conditioning paradigm., The original document contains color images.

Animal research suggests that reactivation (retrieval) of a consolidated memory can return it to a labile state from which it must be restabilized in order to persist. This stabilization process has been termed reconsolidation , and various behavioral and pharmacological interventions have been found to modify or block it. The aim of this project is to create an experimental assay in the form of an optimal Pavlovian differential fear-conditioning paradigm, within which the relative strengths of various pharmacological and behavioral, reconsolidation-blocking interventions can be tested. Thus far, we have completed the testing for the pharmacological intervention group and are continuing the recruitment for the behavioral intervention group. Data from the pharmacological group demonstrate that participants show differential conditioning learning on Day 1, supporting the validity of our modified fear-conditioning paradigm. Results suggest that propranolol administration at the time of memory reactivation does not decrease the fear memory, as indexed by skin conductance, when assessing renewal and reinstatement. When looking at spontaneous recovery at Day 30, results suggest the emergence of a latent effect, which remains to be confirmed and understood better. The addition of a placebo control group is needed to make a conclusive statement about the efficacy of propranolol., The original document contains color images.

Post-traumatic stress disorder (PTSD) symptoms include behavioral avoidance which is acquired and tends to increase with time. This avoidance may represent a general learning bias; indeed, individuals with PTSD are often faster than controls on acquiring conditioned responses based on physiologically-aversive feedback. However, it is not clear whether this learning bias extends to cognitive feedback, or to learning from both reward and punishment. Here, male veterans with self-reported current, severe PTSD symptoms (PTSS group) or with few or no PTSD symptoms (control group) completed a probabilistic classification task that included both reward-based and punishment-based trials, where feedback could take the form of reward, punishment, or an ambiguous no-feedback outcome that could signal either successful avoidance of punishment or failure to obtain reward. The PTSS group outperformed the control group in total points obtained; the PTSS group specifically performed better than the control group on reward-based trials, with no difference on punishment-based trials. To better understand possible mechanisms underlying observed performance, we used a reinforcement learning model of the task, and applied maximum likelihood estimation techniques to derive estimated parameters describing individual participants behavior. Estimations of the reinforcement value of the no-feedback outcome were significantly greater in the control group than the PTSS group, suggesting that the control group was more likely to value this outcome as positively reinforcing (i.e., signaling successful avoidance of punishment). This is consistent with the control group s generally poorer performance on reward trials, where reward feedback was to be obtained in preference to the no-feedback outcome. Differences in the interpretation of ambiguous feedback may contribute to the facilitated reinforcement learning often observed in PTSD patients, and may in turn provide new insight into how patho, Pub. in PLoS ONE, v8 n8, p1-13, August 2013. The original document contains color images.

BackgroundWomen are twice as likely as men to develop Posttraumatic Stress Disorder (PTSD). Abnormal acquisition of conditioned fear has been suggested as a mechanism for the development of PTSD. While some studies of healthy humans suggest that women are either no different or express less conditioned fear responses during conditioning relative to men, differences in the acquisition of conditioned fear between men and women diagnosed with PTSD has not been examined.MethodsThirty-one participants (18 men; 13 women) with full or subsyndromal PTSD completed a fear conditioning task. Participants were shown computer-generated colored circles that were paired (CS+) or unpaired (CS-) with an aversive electrical stimulus and skin conductance levels were assessed throughout the task.ResultsRepeated measures ANOVA indicated a significant sex by stimulus interaction during acquisition. Women had greater differential conditioned skin conductance responses (CS + trials compared to CS- trials) than did men, suggesting greater acquisition of conditioned fear in women with PTSD.ConclusionsIn contrast to studies of healthy individuals, we found enhanced acquisition of conditioned fear in women with PTSD. Greater fear conditioning in women may either be a pre-existing vulnerability trait or an acquired phenomenon that emerges in a sex-dependent manner after the development of PTSD. Characterizing the underlying mechanisms of these differences is needed to clarify sex-related differences in the pathophysiology of PTSD.