Presence Of Memory Research Articles

Increased Natural Killer (NK)-cell cytotoxicity and Trypanosoma cruzi-specific memory B cells in subjects with discordant serology for Chagas disease

The presence of memory T cell specific for Trypanosoma cruzi in subjects with discordant serology for Chagas disease supports a cleared infection in these subjects. Using high-dimensional flow cytometry, ELISPOT assays and quantitative PCR, antibody-secreting cells and memory B cells specific for T. cruzi, total B-cell phenotypes, innate immune responses and parasite DNA were evaluated in serodiscordant, seropositive and seronegative subjects for T. cruzi infection. T. cruzi-specific memory B cells but no antibody-secreting cells specific for T. cruzi, increased proportion of nonclassical monocytes and increased levels of polyfunctional NK cells were found in serodiscordant compared with seropositive subjects. None of the serodiscordant subjects evaluated showed detectable parasite DNA, most of them did not show cardiac abnormalities and a group of them had had confirmed positive serology for Chagas disease. The unique immune profiles in serodiscordant subjects support that T. cruzi infection was cleared or profoundly controlled in these subjects.

The Presence of Memory Through Materiality, Spatial Configuration, and Collective as A System For Sustainable High-Rise Residence

The Presence of Memory Through Materiality, Spatial Configuration, and Collective as A System For Sustainable High-Rise Residence

Toward Realization of Universal Quantum Teleportation Using Weak Measurements

AbstractIn this manuscript, universal quantum teleportation in the presence of memory or memory‐less dynamics with applications of partial collapse measurement operators is analyzed. These results show that the combined effects of memory or non‐Markovianity, and weak measurements can lead to universal quantum teleportation (UQT). This study involves noise models of physical importance having characteristic Markovian and non‐Markovian regions, allowing one to observe a transition in quantum properties as one switches from non‐Markovian to Markovian dynamics. For this, the effects of different types of non‐Markovianity are characterized for efficient UQT, both due to the retention of correlations for a longer duration and due to information backflow. The memory effects arising from a correlated channel with or without weak measurements are analyzed further. Interestingly, this analysis for a correlated amplitude damping channel shows that memory effects are of significant advantage in minimizing the fidelity deviation. The presence of weak measurements further enhances the realization of UQT in the presence of memory. The ability of memory effects to achieve zero fidelity deviation at non‐zero time is interesting and of experimental importance.

Dynamics of SARS-CoV-2-Specific B Cell Memory Responses in Infected and Vaccinated Individuals.

Coronavirus disease 2019 (COVID-19), caused by the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), rapidly resulted in a pandemic constituting a global health emergency. As an indicator of long-term immune protection from reinfection with the SARS-CoV-2 virus, the presence of memory B cells (MBCs) should be evaluated. Since the beginning of COVID-19 pandemic, several variants of concerns have been detected, including Alpha (B.1.1.7), Beta (B.1.351), Gamma (P.1/B.1.1.28.1), Delta (B.1.617.2), and Omicron (BA.1) variants with several different mutations, causing serious concern regarding the increased frequency of reinfection, and limiting the effectiveness of the vaccine response. At this regard, we investigated SARS-CoV-2-specific cellular immune responses in four different cohorts: COVID-19, COVID-19 infected and vaccinated, vaccinated, and negative subjects. We found that MBC response to SARS-CoV-2 at more than 11 months postinfection was higher in the peripheral blood of all COVID-19 infected and vaccinated subjects respect to all the other groups. Moreover, to better characterize the differences of SARS-CoV-2 variants immune responses, we genotyped SARS-CoV-2-positive samples from the patients' cohort. We found a higher level of immunoglobulin M+ (IgM+) and IgG+ spike MBCs in SARS-CoV-2-positive patients (5-8 months after symptoms onset) infected with the SARS-CoV-2-Delta variant compared with the SARS-CoV-2-Omicron variant implying a higher immune memory response. Our findings showed that MBCs persist more than 11 months after primary infection indicating a different involvement of the immune system according to the different SARS-CoV-2 variant that infected the host.

Models and methods for analyzing complex networks and social network structures

Objectives. The study aimed to investigate contemporary models, methods, and tools used for analyzing complex social network structures, both on the basis of ready-made solutions in the form of services and software, as well as proprietary applications developed using the Python programming language. Such studies make it possible not only to predict the dynamics of social processes (changes in social attitudes), but also to identify trends in socioeconomic development by monitoring users’ opinions on important economic and social issues, both at the level of individual territorial entities (for example, districts, settlements of small towns, etc.) and wider regions.Methods. Dynamic models and stochastic dynamics analysis methods, which take into account the possibility of self-organization and the presence of memory, are used along with user deanonymization methods and recommendation systems, as well as statistical methods for analyzing profiles in social networks. Numerical modeling methods for analyzing complex networks and processes occurring in them are considered and described in detail. Special attention is paid to data processing in complex network structures using the Python language and its various available libraries.Results. The specifics of the tasks to be solved in the study of complex network structures and their interdisciplinarity associated with the use of methods of system analysis are described in terms of the theory of complex networks, text analytics, and computational linguistics. In particular, the dynamic models of processes observed in complex social network systems, as well as the structural characteristics of such networks and their relationship with the observed dynamic processes including using the theory of constructing dynamic graphs are studied. The use of neural networks to predict the evolution of dynamic processes and structure of complex social systems is investigated. When creating models describing the observed processes, attention is focused on the use of computational linguistics methods to extract knowledge from text messages of users of social networks.Conclusions. Network analysis can be used to structure models of interaction between social units: people, collectives, organizations, etc. Compared with other methods, the network approach has the undeniable advantage of operating with data at different levels of research to ensure its continuity. Since communication in social networks almost entirely consists of text messages and various publications, almost all relevant studies use textual analysis methods in conjunction with machine learning and artificial intelligence technologies. Of these, convolutional neural networks demonstrated the best results. However, the use of support vector and decision tree methods should also be mentioned, since these contributed considerably to accuracy. In addition, statistical methods are used to compile data samples and analyze obtained results.

The art of augmented memory: Remembering with augmented reality application in the case of the Temple of Artemis

Abstract This article focuses on the effects of different representation modes of architectural heritage in augmented reality (AR) applications on remembering. Deterioration of the tangible evidence of architectural heritage compromises not only its visibility in the heritage site, but also its presence in memory. Converging survived features and digitally produced representations of the heritage, AR applications in mobile devices provide the memory of the site with endurance, however what is remembered immensely depends on how the heritage is digitally represented on screen. Conceived as a case study for the method of analysis derived from classical memorizing technique of the art of memory, the ‘[AR]temis’ project, reported in this article, aimed to get insights into the effects of the representational qualities of augmented architectural heritage on remembering and also into future AR projects developed for architectural heritage sites with its original method of analysis to inform design decisions. The research project involved the development of the method of art of augmented memory, the AR application, as well as questionnaires and interviews with the respondents’ on-site tests of the application. The results of this analysis show that the decisions regarding the digital representation of architectural heritage in AR applications entail not only the visual qualities of the heritage per se, but also how the actual site of memory is visualized on screen.

Memory T cell responses in seronegative older adults following SARS-CoV-2 vaccination.

Generating memory T cell responses besides humoral immune responses is essential when it comes to the efficacy of a vaccine. In this study, the presence of memory T cell responses after aluminum-adjuvanted inactivated whole-virion SARS-CoV-2 vaccine (CoronaVac) in seronegative and seropositive elderly individuals were examined. CD4+ and CD8+ memory T cell proliferation and IFN-γ production capacities were evaluated. Additionally, clinical frailty scale (CFS) and FRAIL scales of the individuals were scored. CD4+ memory T cell responses more prominent than CD8+ memory T cells. In seronegative individuals, 80% of them had memory CD4+ and IFN-γ, whereas 50% of them had memory CD4+ and all of them had IFN-γ responses. Additionally, 40% of seronegative patients and 50% of seropositive patients had memory CD8+ responses. To sum up, humoral immune responses are not associated with memory T cell responses, and in seronegative individuals, memory T cell responses can be detected.

Transfer Behaviour: Is Intention or Memory First? A Model of the Nearest Training Transfer Antecedents

In real life, there is a relationship between a person’s intention and memory. In addition, both are crucial antecedents of behaviour. This study puts this concept under empirical analysis. Additionally, high loss of training memory (50% after 24 hours) is a critical problem. Therefore, a weak understanding of intention and memory unity (interchangeable relationship) would exaggerate the transfer behaviour problem. It should be noted that billions of dollars are lost because of the low training implications (transfer). In that context, the researchers raise the question of ‘what comes first: intention or memory?’ and conduct a holistic statistical analysis. They apply a quantitative method (self-report survey) to test five hypotheses of this study’s variables: (i) intention to transfer (behaviour), (ii) training retention (memory), (iii) training transfer (behaviour). The study participants are 425 (population = 52,000) governmental (ministries) employees. The researchers derive and adapt the study questionnaire from reliable resources. They apply statistical analysis using PLS-SEM – SmartPLS software 3.0. All five hypotheses are accepted. This shows a highly interchangeable role of intention and memory against behaviour. However, the results analysis reveals that intention comes first, with a prominent presence of memory. Practically, it is suitable to understand intention and memory in combination, especially in the design phase. This would enhance the professionalism of behaviour control and effectiveness. For the theoretical tendency of the current study, the managerial implication is challenging. However, it opens the door for other interested researchers to specify a clear and smart solution for this case. In addition, this study has several values. It reconciles two theories in different fields: transfer model (training) with theory of planned behaviour (psychology). Mainly, it empirically describes the relationship between the most important behaviour antecedents (intention and memory). It helps to solve two practical problems: low training implication and high loss of training memory. 
  

Particle dynamics in viscoelastic media: Effects of non-thermal white noise on barrier crossing rates.

The growing interest in the dynamics of self-driven particle motion has brought increased attention to the effects of non-thermal noise on condensed phase diffusion. Thanks to data recently collected by Ferrer et al. on activated dynamics in the presence of memory [Phys. Rev. Lett. 126, 108001 (2021)], some of these effects can now be characterized quantitatively. In the present paper, the data collected by Ferrer et al. are used to calculate the extent to which non-thermal white noise alters the time taken by single micron-sized silica particles in a viscoelastic medium to cross the barrier separating the two wells of an optically created bistable potential. The calculation-based on a generalized version of Kramers's flux-over-population approach-indicates that the added noise causes the barrier crossing rate (compared to the noise-free case) to first increase as a function of the noise strength and then to plateau to a constant value. The precise degree of rate enhancement may depend on how the data from the experiments conducted by Ferrer et al. are used in the flux-over-population approach. As claimed by Ferrer et al., this approach predicts barrier crossing times for the original silica-fluid system that agree almost perfectly with their experimental counterparts. However, this near-perfect agreement between theory and experiment is only achieved if the theoretical crossing times are obtained from the most probable values of a crossing time distribution constructed from the distributions of various parameters in Kramers's rate expression. If the mean values of these parameters are used in the expression instead, as would be commonly done, the theoretical crossing times are found to be as much as 1.5 times higher than the experimental values. However, these times turn out to be consistent with an alternative model of viscoelastic barrier crossing based on a mean first passage time formalism, which also uses mean parameter values in its rate expression. The rate enhancements predicted for barrier crossing under non-thermal noise are based on these mean parameter values and are open to experimental verification.

Emergent Memory and Kinetic Hysteresis in Strongly Driven Networks

Stochastic network-dynamics are typically assumed to be memory-less. Involving prolonged dwells interrupted by instantaneous transitions between nodes such Markov networks stand as a coarse-graining paradigm for chemical reactions, gene expression, molecular machines, spreading of diseases, protein dynamics, diffusion in energy landscapes, epigenetics and many others. However, as soon as transitions cease to be negligibly short, as often observed in experiments, the dynamics develops a memory. That is, state-changes depend not only on the present state but also on the past. Here, we establish the first thermodynamically consistent -- dissipation-preserving -- mapping of continuous dynamics onto a network, which reveals ingrained dynamical symmetries and an unforeseen kinetic hysteresis. These symmetries impose three independent sources of fluctuations in state-to state kinetics that determine the `flavor of memory'. The hysteresis between the forward/backward in time coarse-graining of continuous trajectories implies a new paradigm for the thermodynamics of active molecular processes in the presence of memory, that is, beyond the assumption of local detailed balance. Our results provide a new understanding of fluctuations in the operation of molecular machines as well as catch-bonds involved in cellular adhesion.

Information leak and incompatibility of physical context: A modified approach

A beautiful idea about the incompatibility of physical context (IPC) was introduced in Phys. Rev. A 102, 050201(R) (2020). Here, a context is defined as a set of a quantum state and two sharp rank-one measurements, and the incompatibility of physical context is defined as the leakage of information while implementing those two measurements successively in that quantum state. In this work, we show the limitations in their approach. The three primary limitations are that (i) their approach is not generalized for positive operator-valued measurements; (ii) they restrict information theoretic agents Alice, Eve, and Bob to specific quantum operations and do not consider most general quantum operations, i.e., quantum instruments; and (iii) their measure of IPC can take negative values in specific cases in a more general scenario, which implies the limitation of their information measure. Thereby, we have introduced a generalization and modification to their approach in a more general and convenient way, such that this idea is well defined for generic measurements, without these limitations. We also present a comparison of the measure of the IPC through their and our methods. Lastly, we show, how the IPC reduces in the presence of memory using our modification, which further validates our approach.

Tourist and recreational complex elements dynamics research data analysis qualitative methods

This article presents the results the adapted complex methodology operation for the pre-estimating analysis of the dynamics of tourist flow time series decomposition in the Dombai ski village, the features of which are in the combined use of both classical and new “nonlinear” statistics. The methods proposed and tested by the authors are presented in the form of a pre-estimating model for assessing the tourist flow time series trend stability. The following methods of nonlinear dynamics were tested: the method of the normalized Hurst range, phase-plane analysis. The methods of fractal analysis used and adapted by the authors ensure the identification and assessment of a number of socio-economic time series fundamental qualitative and quantitative pre-estimating characteristics, namely, the presence of memory, including long-term memory, its depth, which in turn can determine the process as persistent (antipersistent, trend-resistant or reverse) to reveal the noise color.

Art, Activism, and the Presence of Memory in Palestine

Abstract In this interview conducted by Lila Abu-Lughod on October 17, 2020, Palestinian artist Rana Bishara discusses the three artworks that appear on the covers of volume 41 of Comparative Studies of South Asia, Africa and the Middle East, as well as numerous other multidisciplinary and multimedia artworks she has made and exhibited from the 1990s to the present, focusing specifically on art as a form of political activism.

Functional responsiveness of memory T cells from COVID-19 patients

The presence of memory T cells in COVID-19 patients has been acknowledged, however the functional potency of memory responses is critical for protection. In this study, naïve, effector, effector memory, and central memory CD4+ and CD8+ T cells obtained from the COVID-19 survivors were re-exposed to autologous monocyte-derived DCs that were loaded with SARS-CoV-2 spike glycoprotein S1. Proliferation capacity, CD25, 4-1BB, and PD-1 expression, and IFN-γ, IL-6, granzyme, granulysin, and FasL secretion were enhanced in CD4+ and CD8+ effector memory and central memory T cells. Albeit being at heterogeneous levels, the memory T cells from the individuals with COVID-19 history possess functional capacities to reinvigorate anti-viral immunity against SARS-CoV-2.

Early Antibody-Mediated Rejection in Non-Pre-Sensitized Heart Transplant Recipient

Introduction Antibody-mediated rejection (AMR) is an important cause of allograft dysfunction. It usually occurs after the first month of heart transplant (HT), but an early presentation is possible. We present an unusual case of a female HT recipient who had early AMR with no evidence of pre-sensitization to the donor. Case Report A woman, 45 years old, idiopathic dilated cardiomyopathy, two kids, with previous negative panel reactive antibody (PRA) was submitted to HT with success. The prospective crossmatch was negative and she did not receive blood cells during the surgery. The donor was a woman, 47 years old, who had a hemorrhagic stroke. After the procedure, she needed low doses of vasoactive drugs, received immunosuppression therapy according to institutional protocol and maintained normal ventricular function. On the 5th day, she developed biventricular graft dysfunction (left ventricular ejection fraction of 40%) requiring inotropes. The PRA revealed a donor specific antibody (DSA) not previously detected and the result of endomyocardial biopsy (EMB) confirmed acute AMR (pAMR2). Patient was successfully treated with methylprednisolone, plasmapheresis, immunoglobulin and rituximab. Biventricular function recovered; no DSA was detected and new EMB showed no rejection findings. Summary AMR results from recipient antibodies against donor-HLA antigens, causing complement activation, inflammation and injury to the allograft endothelium. In general, it occurs in the first two months after HT due to a rise in DSA by the contact with donor-HLA antigens. Early AMR, that occurs in the first week, is related to pre-sensitization to donor HLA antigens and associated with graft dysfunction. In this case report, no previous antibody had been detected. Two possibilities could explain such findings: the presence of non-HLA antibodies or the presence of memory B cells with levels of DSA too low to be detected on PRA. This case highlights the importance of monitoring antibodies in HT recipients with early allograft dysfunction even with previous negative PRA.

Sigma-Pi Structure with Bernoulli Random Variables: Power-Law Bounds for Probability Distributions and Growth Models with Interdependent Entities.

The Sigma-Pi structure investigated in this work consists of the sum of products of an increasing number of identically distributed random variables. It appears in stochastic processes with random coefficients and also in models of growth of entities such as business firms and cities. We study the Sigma-Pi structure with Bernoulli random variables and find that its probability distribution is always bounded from below by a power-law function regardless of whether the random variables are mutually independent or duplicated. In particular, we investigate the case in which the asymptotic probability distribution has always upper and lower power-law bounds with the same tail-index, which depends on the parameters of the distribution of the random variables. We illustrate the Sigma-Pi structure in the context of a simple growth model with successively born entities growing according to a stochastic proportional growth law, taking both Bernoulli, confirming the theoretical results, and half-normal random variables, for which the numerical results can be rationalized using insights from the Bernoulli case. We analyze the interdependence among entities represented by the product terms within the Sigma-Pi structure, the possible presence of memory in growth factors, and the contribution of each product term to the whole Sigma-Pi structure. We highlight the influence of the degree of interdependence among entities in the number of terms that effectively contribute to the total sum of sizes, reaching the limiting case of a single term dominating extreme values of the Sigma-Pi structure when all entities grow independently.

Short- and long-term memory of moving amoeboid cells.

Amoeboid cells constantly change shape and extend protrusions. The direction of movement is not random, but is correlated with the direction of movement in the preceding minutes. The basis of this correlation is an underlying memory of direction. The presence of memory in movement is known for many decades, but its molecular mechanism is still largely unknown. This study reports in detail on the information content of directional memory, the kinetics of learning and forgetting this information, and the molecular basis for memory using Dictyostelium mutants. Two types of memory were characterized. A short-term memory stores for ~20 seconds the position of the last pseudopod using a local modification of the branched F-actin inducer SCAR/WAVE, which enhances one new pseudopod to be formed at the position of the previous pseudopod. A long term memory stores for ~2 minutes the activity of the last ~10 pseudopods using a cGMP-binding protein that induces myosin filaments in the rear of the cell; this inhibits pseudopods in the rear and thereby enhances pseudopods in the global front. Similar types of memory were identified in human neutrophils and mesenchymal stem cells, the protist Dictyostelium and the fungus B.d. chytrid. The synergy of short- and long-term memory explains their role in persistent movement for enhanced cell dispersal, food seeking and chemotaxis.

When Is a Non-Markovian Quantum Process Classical?

More than a century after the inception of quantum theory, the question of which traits and phenomena are fundamentally quantum remains under debate. Here we give an answer to this question for temporal processes which are probed sequentially by means of projective measurements of the same observable. Defining classical processes as those that can---in principle---be simulated by means of classical resources only, we fully characterize the set of such processes. Based on this characterization, we show that for non-Markovian processes (i.e., processes with memory), the absence of coherence does not guarantee the classicality of observed phenomena and furthermore derive an experimentally and computationally accessible measure for non-classicality in the presence of memory. We then provide a direct connection between classicality and the vanishing of quantum discord between the evolving system and its environment. Finally, we demonstrate that---in contrast to the memoryless setting---in the non-Markovian case, there exist processes that are genuinely quantum, i.e., they display non-classical statistics independent of the measurement scheme that is employed to probe them.

Effects of reproductive skew on the evolution of ethnocentrism in structured populations with variable size

Large-scale cooperation is arguably one of the most astonishing achievements of humankind. In spite of its global abundance, members of many species, including humans, tend to direct their generosity exclusively towards phenotypically similar group-mates, thereby elevating the levels of intergroup tension and ingroup biased ethnocentrism. Recent studies have evidenced, however, that stable dominance of ethnocentric cooperation is endangered in the presence of memory, mobility, conformity, or link undirectedness in structured populations. In the present paper, we investigated the heterogeneity of reproductive time scales as a possible mechanism for the reduction of ethnocentric behavior and the promotion of global unconditional cooperation in phenotypically diverse populations with demographic fluctuations. To this effect, the regular reproduction stage that typically follows the interaction of agents in the evolutionary process of the ethnocentrism model is discarded. Instead, agents reproduce in accordance with their assigned reproduction times that obey a power-law distribution. Unlike the standard model of ethnocentric cooperation with proportional selection, we found that reproductive skew can elevate cooperation also by promoting non-ethnocentric strategies such as global altruism and conditional extra-group cooperation, while simultaneously reducing ethnocentric behavior. However, we found that this ethnocentrism-controlling potency of reproductive heterogeneity depends on the underlying population structure, with more pronounced effects on Barabási–Albert scale-free networks than on regular square lattices. With an increasing power-law exponent of the reproduction-time distribution, we identified a remarkable coexistence of strategies that was not reported in previous models of tag-based cooperation. Our further simulations revealed that this strategy coexistence varied with the fluctuating population size which in turn depended on the correlation between the node connectivity and the reproduction rate of individual agents. Our findings highlight the importance of reproductive skew and the relationship between node degree and reproduction rate for the stability of intra-group generosity in structured populations, potentially explaining the widespread coexistence of strategies in phenotypically diverse societies.

A thermodynamic uncertainty relation for a system with memory

We introduce an example of thermodynamic uncertainty relation (TUR) for systems modeled by a generalised Langevin dynamics with memory, determining the motion of a micro-bead driven in a complex fluid. Contrary to TURs typically discussed in the previous years, our observables and the entropy production rate are one-time variables. The bound to the signal-to-noise ratio (SNR) of such state-dependent observables can only in some cases be mapped to the entropy production rate. For example, this is true for steady states and for a subclass of Markovian systems. In fact, the presence of memory in the system complicates the thermodynamic interpretation of the uncertainty relation.