underlying processes
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2022 ◽  
Vol 215 ◽  
pp. 105319
Author(s):  
Anne-Merel Meijer ◽  
Bart Aben ◽  
Bert Reynvoet ◽  
Eva Van den Bussche

Author(s):  
Tali M. Ball ◽  
Lisa A. Gunaydin

AbstractAvoiding stimuli that predict danger is required for survival. However, avoidance can become maladaptive in individuals who overestimate threat and thus avoid safe situations as well as dangerous ones. Excessive avoidance is a core feature of anxiety disorders, post-traumatic stress disorder (PTSD), and obsessive-compulsive disorder (OCD). This avoidance prevents patients from confronting maladaptive threat beliefs, thereby maintaining disordered anxiety. Avoidance is associated with high levels of psychosocial impairment yet is poorly understood at a mechanistic level. Many objective laboratory assessments of avoidance measure adaptive avoidance, in which an individual learns to successfully avoid a truly noxious stimulus. However, anxiety disorders are characterized by maladaptive avoidance, for which there are fewer objective laboratory measures. We posit that maladaptive avoidance behavior depends on a combination of three altered neurobehavioral processes: (1) threat appraisal, (2) habitual avoidance, and (3) trait avoidance tendency. This heterogeneity in underlying processes presents challenges to the objective measurement of maladaptive avoidance behavior. Here we first review existing paradigms for measuring avoidance behavior and its underlying neural mechanisms in both human and animal models, and identify how existing paradigms relate to these neurobehavioral processes. We then propose a new framework to improve the translational understanding of maladaptive avoidance behavior by adapting paradigms to better differentiate underlying processes and mechanisms and applying these paradigms in clinical populations across diagnoses with the goal of developing novel interventions to engage specific identified neurobehavioral targets.


2022 ◽  
Vol 13 ◽  
Author(s):  
Amandine Mayelle ◽  
Capucine Hazebrouck ◽  
Mohamad El Haj ◽  
Daniel C. Mograbi ◽  
Pascal Antoine

Objective: To understand awareness and fluctuations of awareness in Alzheimer’s disease (AD), it is fruitful to consider the objects of awareness, e.g., cognitive functioning or recognition of the disease, as well as the mechanisms and modes of expression underlying awareness. With a holistic and discourse-centered approach, we aimed to identify different awareness profiles and test whether these profiles were stable or whether transitions from one profile to another occurred over short time intervals.Methods: Twenty-eight residents of nursing homes with a diagnosis of AD participated in four semistructured interviews at biweekly intervals. These interviews were cluster analyzed to determine profiles of awareness. A Markov chain was applied to model their fluctuation.Results: Five awareness profiles were observed that differed in terms of objects and underlying processes. Awareness proved to be quite stable for four of the five profiles. Interindividual variability in awareness was also observed through numerous different trajectories that were identified.Discussion: Self-awareness and disease awareness are characterized by profiles that vary subtly between individuals. Fluctuations in awareness underscore the need to employ assessment intervals that closely reflect daily life in institutions.


2022 ◽  
Author(s):  
Stefania Impellizzeri ◽  
Gregory J, Hodgson ◽  
Nicholas P. Dogantzis

<p>Plasmonic metal nanoparticles can impact the behaviour of organic molecules in a number of ways, including enhancing or quenching fluorescence. Only through a comprehensive understanding of the fundamental photophysical processes regulating nano-molecular interactions can these effects be controlled, and exploited to the fullest extent possible. Metal-enhanced fluorescence (MEF) is governed by two underlying processes, increased rate of fluorophore excitation and increased fluorophore emission, the balance between which has implications for optimizing hybrid nanoparticle-molecular systems for various applications. We report groundbreaking work on the use of single molecule fluorescence microscopy to distinguish between the two mechanistic components of MEF, in a model system consisting of two analogous boron dipyrromethene (BODIPY) fluorophores and triangular silver nanoparticles (AgNP). We demonstrate that the increased excitation MEF mechanism occurs to approximately the same extent for both dyes, but that the BODIPY with the higher quantum yield of fluorescence experiences a greater degree of MEF via the increased fluorophore emission mechanism, and higher overall enhancement, as a result of its superior ability to undergo near-field interactions with AgNP. We foresee that this knowledge and methodology will be used to tailor MEF to meet the needs of different applications, such as those requiring maximum enhancement of fluorescence intensity or instead prioritizing excited-state photochemistry. </p>


2022 ◽  
Author(s):  
Stefania Impellizzeri ◽  
Gregory J, Hodgson ◽  
Nicholas P. Dogantzis

<p>Plasmonic metal nanoparticles can impact the behaviour of organic molecules in a number of ways, including enhancing or quenching fluorescence. Only through a comprehensive understanding of the fundamental photophysical processes regulating nano-molecular interactions can these effects be controlled, and exploited to the fullest extent possible. Metal-enhanced fluorescence (MEF) is governed by two underlying processes, increased rate of fluorophore excitation and increased fluorophore emission, the balance between which has implications for optimizing hybrid nanoparticle-molecular systems for various applications. We report groundbreaking work on the use of single molecule fluorescence microscopy to distinguish between the two mechanistic components of MEF, in a model system consisting of two analogous boron dipyrromethene (BODIPY) fluorophores and triangular silver nanoparticles (AgNP). We demonstrate that the increased excitation MEF mechanism occurs to approximately the same extent for both dyes, but that the BODIPY with the higher quantum yield of fluorescence experiences a greater degree of MEF via the increased fluorophore emission mechanism, and higher overall enhancement, as a result of its superior ability to undergo near-field interactions with AgNP. We foresee that this knowledge and methodology will be used to tailor MEF to meet the needs of different applications, such as those requiring maximum enhancement of fluorescence intensity or instead prioritizing excited-state photochemistry. </p>


Author(s):  
Asmaa K. Abdelghany ◽  
Akram M. El-Kashlan ◽  
Hosny H. Emeash ◽  
Fatma Khalil

Abstract Background Animal models are used to provide an adequate investigation of brain-behaviour, physiological and path physiological relationships to give insight into human behaviour and the underlying processes of drugs affecting the nervous system. Scopolamine; SCO (alkaloid l-(2)-scopolamine [l-(2)-hyoscine]) has a competitive inhibitory effect on muscarinic receptors for acetylcholine. Thus, this study was designated to investigate the effect of long-term SCO treatment on locomotor, exploratory and anxiety-like behaviours of rats using open field test. Results The long-term SCO treatment induced a prominent increase in locomotion (hyperactivity) and exploratory behaviour of rats. In addition, anxiety-like behavioural patterns showed a non-significant difference in SCO treated compared to control. Serotonin level was significantly decreased in the scopolamine treated group in comparison with the control group. Conclusions Data suggested that long-term SCO treatment resulted in marked neurobehavioural alterations in a rat as an animal model.


Polymers ◽  
2021 ◽  
Vol 14 (1) ◽  
pp. 121
Author(s):  
Till Krieg ◽  
Cristian Mazzon ◽  
Elena Gómez-Sánchez

Identifying the most vulnerable plastics and monitoring their deterioration is one of the main problems within heritage collections with historical synthetic polymers. Gathering and interpreting data about material and degradation phenomena in a collection reveals its conservation needs. A systematic survey of the collection can help towards this purpose. Surveys aiming at inspecting and documenting damages rely on several tools in order to fulfill their purpose. Firstly, objective descriptions of the damages that may appear, and secondly, the means of acquiring and interpreting material information. To address these needs, this article presents (a) a visual damage catalogue of degradation phenomena in plastic and rubber materials, and (b) the implementation of Fourier-transform infrared spectroscopy (FTIR) and pyrolysis–gas chromatography–mass spectrometry (py-GCMS) for the identification of analytically challenging rubber materials and of blooming phenomena. The damage catalogue is based solely on visual and olfactory signs, so that the assessment is independent of possible causes of damages and underlying processes, with the purpose of allowing objectivity to prime over interpretation. The limitations of the use of FTIR in the identification of heavily compounded rubbers in museum surveys is highlighted, and examples are presented. The use of py-GCMS on these cases conveniently allowed the identification of the constituting monomers of several rubber materials where FTIR could not provide a univocal classification of the material present. The study of several cases of blooming allowed the identification of diverse compositions and origins, showing that the description of a degradation phenomenon is only the first step towards its understanding. Unveiling the nature of a particular case of blooming is particularly critical when conservation treatments, such as the removal of a (potentially protecting) layer, are planned. For this purpose, attenuated total reflection-FTIR (ATR-FTIR) as a surface technique was particularly useful.


2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Trudie Walters ◽  
Najmeh Hassanli ◽  
Wiebke Finkler

PurposeIn this paper the authors seek to understand how academic conferences [re]produce deeply embedded gendered patterns of interaction and informal norms within the business disciplines.Design/methodology/approachDrawing on Acker's (2012) established and updated theory of gendered organisations, the authors focus on the role of academic conferences in the reproduction of gendered practices in the business disciplines. The authors surveyed academics at top universities in Australia and New Zealand who had attended international conferences in their discipline area.FindingsAcademic conferences in the business disciplines communicate organisational logic and act as gendered substructures that [re]produce gendered practices, through the hierarchy of conference participation. Even in disciplinary conferences with a significant proportion of women delegates, the entrenched organisational logic is manifest in the bodies that perform keynote and visible expert roles, perpetuating the notion of the “ideal academic” as male.Practical implicationsThe authors call for disciplinary associations to formulate an equality policy, which covers all facets of conference delivery, to which institutions must then respond in their bid to host the conference and which then forms part of the selection criteria; explicitly communicate why equality is important and what decisions the association and hosts took to address it; and develop databases of women experts to remove the most common excuse for the lack of women keynote speakers. Men, question conference hosts when asked to be a keynote speaker or panelist: Are half of the speakers women and is there diversity in the line-up? If not, provide the names of women to take your place.Originality/valueThe contribution of this study is twofold. First is the focus on revealing the underlying processes that contribute to the [re]production of gender inequality at academic conferences: the “how” rather than the “what”. Second, the authors believe it to be the first study to investigate academic conferences across the spectrum of business disciplines.


2021 ◽  
pp. 47-54
Author(s):  
Mitra Heidari ◽  
G. Venkatesh Kumar

Emotion, both positive and negative, is one of the markers of intimate relationships. Attachment theory is one of the primary conceptual frameworks for understanding emotion regulation. There is a well-established link in the literature between secure romantic attachment style and emotional intelligence (EI) in scientic studies. The underlying processes of this link among couples are notably less explored in the Indian context. As an attempt to bridge the gap, the present study analyzed the inuence of attachment styles and EI interplay on marital satisfaction among Indian couples. The study considered 304 respondents (152 females, 152 males, ranged from -25 to 65+ years old) with a marriage duration greater than three years. To assess participants attachment styles, EI, and marital satisfaction, Revised Adult Attachment Scale (RAAS; Collins, 1996), Trait Emotional Intelligence Questionnaire (TEIQue; Petrides, 2009) and ENRICH Marital Satisfaction Scale (EMS; Fowers & Olson, 1993) were used respectively. Two-way ANOVA was used to analyse the data. The result revealed that there is a signicant interaction between attachment styles and global EI on marital satisfaction. Psychotherapists and counsellors in general, and couple therapists in particular, will benet from the current research. Considering the limitation of the study, further investigation is recommended.


2021 ◽  
Author(s):  
Golam T. Saffi ◽  
Emily Mangialardi ◽  
Jean Vacher ◽  
Roberto J. Botelho ◽  
LEONARDO SALMENA

Lysosome membranes contain diverse phosphoinositide (PtdIns) lipids that co-ordinate lysosome function and dynamics. The PtdIns repertoire on lysosomes is tightly regulated by the action of diverse PtdIns kinases and phosphatases. Specific roles for PtdIns in lysosomal function and dynamics are currently unclear and require further investigation. PIKfyve, a lipid kinase which synthesizes PtdIns(3,5)P2 from PtdIns(3)P, controls lysosome fusion-fission cycles, autophagosome turnover and endocytic cargo delivery. We have recently characterized a role for INPP4B, a PtdIns phosphatase which hydrolyses PtdIns(3,4)P2 to form PtdIns(3)P, in the regulation of lysosomal biogenesis and function. To gain a better understanding of PtdIns homeostasis on lysosomes, we investigated the consequence of disrupting PIKfyve in Inpp4b-deficient mouse embryonic fibroblasts. Surprisingly, simultaneous inhibition of Inpp4b and PIKfyve functions impair lysosome fission and exacerbate lysosome enlargement and inhibit autophagic flux. Further examination into the underlying processes that may explain exaggerated lysosome enlargement revealed elevated levels of lysosome-associated PtdIns(3)P as contributing factors that control lysosome morphology in cells where Inpp4b and PIKfyve are disrupted. Overall, our study suggests that lysosomal functions are regulated by Inpp4b, through a paradoxical role in suppressing the induction of PtdIns(3)P production.


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