Independent Trajectories Research Articles

Exploring the developmental changes in and the relationship between resilience and anxiety and depression in older gastric cancer survivors: A latent growth mixture model and random intercept cross-lagged panel model analysis.

This study aims to investigate the independent and joint trajectories of resilience, anxiety, and depression symptoms and research the interaction between older gastric cancer survivors' resilience and anxiety-depression during the period of 1 year after surgery. The participants were 381 older gastric cancer survivors, with a mean age of 69 years. Resilience, anxiety, and depression symptoms were assessed immediately after surgery, and at 3, 6, and 12 months post-surgery, respectively. A longitudinal design was employed to capture the dynamic changes in resilience, anxiety, and depression levels among older gastric cancer survivors post-surgery. Latent growth mixture model and random intercept cross-lagged panel model were used to analyse the trajectories of resilience and anxiety-depression and the interaction between them. Two latent trajectories were identified for the resilience, four latent trajectories were identified for the anxiety, and five latent trajectories were identified for the depression, respectively, with three joint trajectories identified: gradual-increasing resilience, gradual-decreasing anxiety, and depression group (10.0%); gradual-decreasing resilience, gradual-increasing anxiety, and depression group (21.2%); and rapid-growth resilience, rapid-decline anxiety, and depression group (68.8%). Resilience among older gastric cancer survivors exhibits significant bidirectional and negative predictive effects on anxiety and depression. Individual differences in resilience, anxiety, and depression trajectories exist among older gastric cancer survivors, with heterogeneous joint progression patterns, and the relationship between resilience and anxiety-depression appears bidirectional. More sophisticated intervention programmes tailored to the unique characteristics of the relevant trajectories are necessary to enhance resilience and mitigate the risk of anxiety and depression.

Impact of replicas and simulation length on in silico behaviors of a protein domain.

Molecular dynamics (MD) simulations are a powerful tool for life sciences, valuable for their ability to capture atomic-level behavior of molecules over time. To advance knowledge on reasonable timescales, researchers must optimize the amount of useful information extracted from simulation data while frugally managing computational resources. They must balance trajectory lengths and number of replicas, with the aim of maximizing conformational sampling. Identifying this balance is not always intuitive, and lack of standardization among researchers produces variability in results from MD measurements. We investigate how changes in simulation length and replica numbers impact this variability. Using a 231-residue domain, we compare measurements from independent trajectories to a benchmark trajectory of 3x1000-ns replicates. We simulate 27 protein-ligand complexes, allowing us to compare ligand-specific rankings of complexes across replicas. We reveal that some MD measurements are reliably ranked by single trajectories, while others are not. We uncover similar variability in the effects of trajectory lengths on measurements. Our findings suggest that a one-size-fits-all approach to MD simulations is not ideal, and depending on the intended measurements and research question, it is sometimes advantageous to prioritize longer trajectories over multiple replicas. This work provides important considerations for researchers while designing simulation studies.

The Ukraine invasion: Hierarchy, discipline and counterbalance

This article examines Russia’s 2022 military intervention in Ukraine through an eclectic theoretical framework that synthesises hierarchy theory, foreign-imposed regime change, and negative balancing strategy. We argue that Russia justified the attack as a means to protect its hierarchical objectives in the post-Soviet region against three perceived imminent threats: Ukraine’s independent trajectory, the growing alignment of certain post-Soviet states with the US-led hierarchy, and the expansion of the US-led Western hierarchy into the post-Soviet space. In response, Russia employed the hard face of its negative balancing strategy by launching an overt foreign-imposed regime change operation to replace Zelensky’s government with a pro-Moscow regime. From the outset, this operation has been tasked with two key aims: discipline and balance. The disciplinary objective has focused on ensuring Ukraine’s loyalty to Moscow and deterring other Western-leaning post-Soviet states from emulating Ukraine by sending a clear disciplinary message. The balance objective has sought to counter the negative and outbidding strategies of the US-led hierarchy, which Russia perceives as a neo-containment agenda aimed at undermining its regional influence.

Do Tau Deposition and Glucose Metabolism Dissociate in Alzheimer's Disease Trajectory?

Tau aggregation demonstrates close associations with hypometabolism in Alzheimer's disease (AD), although differing pathophysiological processes may underlie their development. To establish whether tau deposition and glucose metabolism have different trajectories in AD progression and evaluate the utility of global measures of these pathological hallmarks in predicting cognitive deficits. 279 participants with amyloid-β (Aβ) status, and T1-weighted MRI scans, were selected from the Alzheimer's Disease Neuroimaging Initiative (http://adni.loni.usc.edu). We created the standard uptake value ratio images using Statistical Parametric Mapping 12 for [18F]AV1451-PET (tau) and [18F]FDG-PET (glucose metabolism) scans. Voxel-wise group and single-subject level SPM analysis evaluated the relationship between global [18F]FDG-PET and [18F]AV1451-PET depending on the Aβ status. Linear models assessed whether tau deposition or glucose metabolism better predicted clinical progression. There was a dissociation between global cerebral glucose hypometabolism and global tau load in amyloid-positive AD and amyloid-negative mild cognitive impairment (MCI) (p > 0.05). Global hypometabolism was only associated with global cortical tau in amyloid-positive MCI. Voxel-level single subject tau load better predicted neuropsychological performance, Alzheimer's disease assessment scale-cognitive (ADAS-Cog) 13 score, and one-year change compared with regional and global hypometabolism. A dissociation between tau pathology and glucose metabolism at a global level in AD could imply that other pathological processes influence glucose metabolism. Furthermore, as tau is a better predictor of clinical progression, these processes may have independent trajectories and require independent consideration in the context of therapeutic interventions.

Exact-factorisation study of the photochemistry of phenol

We present an analysis of the performance of the coupled-trajectory schemes for nonadiabatic dynamics derived from the exact factorisation of the electron-nuclear wavefunction and implemented in the G-CTMQC code. These algorithms can be seen as variations of the standard Ehrenfest method and Tully surface hopping, which are based, however, on independent trajectories. The reported analysis aims to compare the coupled-trajectory and independent-trajectory schemes, and to benchmark the numerical results against exact quantum wavepacket dynamics. To this end, we employ an analytical molecular model with two nuclear degrees of freedom and three electronic states that allows us to describe the photo-induced hydrogen dissociation in phenol. The analysis focuses on different electronic and nuclear properties calculated along the nonadiabatic dynamics of phenol.

Physics constrained pedestrian trajectory prediction with probability quantification

Accurately understanding and predicting the future trajectories of pedestrians around autonomous vehicles is a major challenge. Due to the uncertainty and diversity of pedestrian trajectories, current research focuses on the multimodality of trajectory prediction. Currently, multimodal pedestrian prediction methods mainly use deep generative networks to generate mutually independent trajectories through independent sampling strategy, thus focusing on modes with a large number of samples. Moreover, deep generative networks are black-box models that are entirely data-driven and cannot effectively explain trajectory generation. In addition, current research lacks an effective measure for each trajectory. Therefore, in our paper, we propose a physics constrained pedestrian trajectory prediction with probability quantification. We divide multimodal trajectory prediction into two phases: trajectory generation phase and trajectory selection phase. During the trajectory generation phase, rather than directly predicting trajectories, we incorporate a differential constraint module to ensure that the generated trajectories adhere to pedestrian motion laws. This approach enhances the interpretability of the model prediction process. Subsequently, we generate a set of candidate trajectory proposals with specific correlations through the correlated sampling module. During the trajectory selection phase, a probability selection module is proposed to establish explicit probability distributions for the candidate trajectory proposals and to select the proposal with the highest probability as the final output. Extensive experiments on a public real-world pedestrian trajectory dataset show that our proposed model exhibits significant advantages over existing models in multimodal trajectory prediction, which not only effectively reduces the error but also mitigates mode collapse. Moreover, we provide probabilities for each trajectory to better capture the model uncertainty and provide more comprehensive information for downstream decision-making systems.

Classical Indian Vitalism Found in the Abhidhamma as an Approach to the Hard Problem of Consciousness: Problems and Perspectives

Currently, vitalism stands as a discredited theory in the Western empirical sciences. However, the Indian analytical traditions, specifically the Jaina, Bauddha, Sankhya-Yoga, and the Vedanta, unanimously propose a vital energy “prana” or “jivitindriya” to bridge the explanatory gap between internal conscious states and physical states in the body. The philosophical development of vitalism both in the East and West follows independent and different trajectories. In this article, the view of consciousness as a transient internal state (found in the Abhidhamma) and the modes of its interaction with physical states is critically examined. An attempt is made to find some parallels between the classical Abhidhamma model of consciousness and modern biophysical studies. How the model arose from meditative observation and the status of vital energy prana in mediating the interaction between internal and physical states, is discussed. The article ends by noting the application of these concepts in a therapy found in the Ayurvedic system of medicine.

Exploring Biomolecular Conformational Dynamics with Polarizable Force Field AMOEBA and Enhanced Sampling Method Milestoning.

Conformational dynamics play a crucial role in determining the behavior of the biomolecules. Polarizable force fields, such as AMOEBA, can accurately capture electrostatic interactions underlying the conformational space. However, applying a polarizable force field in molecular dynamics (MD) simulations can be computationally expensive, especially in studying long-time-scale dynamics. To overcome this challenge, we incorporated the AMOEBA potential with Milestoning, an enhanced sampling method in this work. This integration allows us to efficiently sample the rare and important conformational states of a biomolecule by using many short and independent molecular dynamics trajectories with the AMOEBA force field. We applied this method to investigate the conformational dynamics of alanine dipeptide, DNA, and RNA A-B form conversion. Well-converged thermodynamic and kinetic properties were obtained, including the free energy difference, mean first passage time, and critical transitions between states. Our results demonstrate the power of integrating polarizable force fields with enhanced sampling methods in quantifying the thermodynamic and kinetic properties of biomolecules at the atomic level.

A MASH simulation of the photoexcited dynamics of cyclobutanone.

In response to a community prediction challenge, we simulate the nonadiabatic dynamics of cyclobutanone using the mapping approach to surface hopping (MASH). We consider the first 500fs of relaxation following photoexcitation to the S2 state and predict the corresponding time-resolved electron-diffraction signal that will be measured by the planned experiment. 397 abinitio trajectories were obtained on the fly with state-averaged complete active space self-consistent field using a (12,11) active space. To obtain an estimate of the potential systematic error, 198 of the trajectories were calculated using an aug-cc-pVDZ basis set and 199 with a 6-31+G* basis set. MASH is a recently proposed independent trajectory method for simulating nonadiabatic dynamics, originally derived for two-state problems. As there are three relevant electronic states in this system, we used a newly developed multi-state generalization of MASH for the simulation: the uncoupled spheres multi-state MASH method (unSMASH). This study, therefore, serves both as an investigation of the photodissociation dynamics of cyclobutanone, and also as a demonstration of the applicability of unSMASH to abinitio simulations. In line with previous experimental studies, we observe that the simulated dynamics is dominated by three sets of dissociation products, C3H6 + CO, C2H4 + C2H2O, and C2H4 + CH2 + CO, and we interpret our predicted electron-diffraction signal in terms of the key features of the associated dissociation pathways.

Advances in Adjoint Functions of Connection Number in Water Resources Complex Systems: A Systematic Review.

The adjoint function of connection number has unique advantages in solving uncertainty problems of water resource complex systems, and has become an important frontier and research hotspot in the uncertainty research of water resource complex problems. However, in the rapid evolution of the adjoint function, some problems greatly limit the application of the adjoint function in the research of water resources. Therefore, based on bibliometric analysis, development, practical application issues, and prospects of the hot directions are analyzed. It is found that the development of the connection number of water resource set pair analysis can be divided into three stages: (1) relatively sluggish development before 2005, (2) a period of rapid advancement in adjoint function research spanning from 2005 to 2017, and (3) a subsequent surge post-2018. The introduction of the adjoint function of connection number promotes the continuous development of set pair analysis of water resources. Set pair potential and partial connection number are the crucial research directions of the adjoint function. Subtractive set pair potential has rapidly developed into a relatively independent and important trajectory. The research on connection entropy is comparatively less, which needs to be further strengthened, while that on adjacent connection number is even less. The adjoint function of set pair potential can be divided into three major categories: division set pair potential, exponential set pair potential, and subtraction set pair potential. The subtraction set pair potential, which retains the original dimension and quantity variation range of the connection number, is widely used in water resources and other fields. Coupled with the partial connection number, a series of new connection number adjoint functions have been developed. The partial connection number can be mainly divided into two categories: total partial connection number, and semi-partial connection number. Among these, the calculation expression and connotation of total partial connection numbers have not yet reached a consensus, accompanied by the slow development of high-order partial connection numbers. Semi-partial connection number can describe the mutual migration movement between different components of the connection number, which develops rapidly. With the limitations and current situation described above, promoting the exploration and application of the adjoint function of connection number in the field of water resources and other fields of complex systems has become the focus of future research.

Intertwined depressive and cognitive trajectories and the risk of dementia and death in older adults: a competing risk analysis

BackgroundDepressive symptoms and cognitive impairment often interact, rendering their associations controversial. To date, their joint trajectories and associations with dementia and death remain underexplored.AimsTo explore the interactions between depressive symptoms...

Abstract P511: Trajectories of Modifiable Risk Factors, Cardiac Function and Incident Heart Failure in the Atherosclerosis Risk in Communities (ARIC) Cohort

Introduction: Modifiable risk factors are known to associate with incident heart failure (HF), however, their longitudinal impacts have not been fully understood. Independent trajectory clusters of risk factors can help provide insights to the development of HF. Hypothesis: We hypothesize that unfavorable trajectory clusters are associated with increasing risk of HF. Methods: Clinical risk factors, including body mass index (BMI), systolic blood pressure (SBP), low-density lipoprotein (LDL), heart rate, total cholesterol (TCH), and high-density lipoprotein (HDL) were measured in Atherosclerosis Risk in Communities (ARIC) study at 5 consecutive visits (1987-2013). Trajectories were built for each clinical risk factor in participants with at least 3 time points using group-based trajectory modeling approach. Controlling for clinical risk factors, trajectory groups and their associations with post visit 5 incident HF were assessed via Cox proportional regression. Sex stratified analyses were conducted to assess effect modification. Results: Among 4,548 participants (mean age 75, 18.1% Blacks), 390 developed HF after visit 5 (median follow = 8.4 years). Five distinct clusters were identified for SBP, LDL, TCH, heart rate, and three clusters for BMI and HDL. Compared to the lowest cluster, normal-fast rising SBP cluster (HR = 1.7, 95% CI 1.2, 2.5), severely obese BMI cluster (HR = 1.9, 95%CI 1.4, 2.6), and normal-fast rising heart rate cluster (HR = 1.7, 95%CI 1.1, 2.5) had higher risk of developing HF. Interestingly, suboptimal-stable LDL cluster (HR = 0.6, 95%CI 0.4, 0.8) was associated with lower risk of HF compared to the optimal-stable LDL cluster. When stratified by sex (female =59.1%, male = 40.9%), the identified trajectories shared similar patterns with the parent trajectories. The effects on HF were consistent between sex groups; however, most significant associations were diminished in males. Conclusion: We identified distinct trajectories that capture long-term effects of risk factors. Unfavorable clusters significantly associated with increased risk of HF, except LDL, suggesting further investigation on lipids control for HF prevention.

Social network shrinking is explained by active and passive effects but not increasing selectivity with age in wild macaques.

Evidence of social disengagement, network narrowing and social selectivity with advancing age in several non-human animals challenges our understanding of the causes of social ageing. Natural animal populations are needed to test whether social ageing and selectivity occur under natural predation and extrinsic mortality pressures, and longitudinal studies are particularly valuable to disentangle the contribution of within-individual ageing from the demographic processes that shape social ageing at the population level. Data on wild Assamese macaques (Macaca assamensis) were collected between 2013 and 2020 at the Phu Khieo Wildlife Sanctuary, Thailand. We investigated the social behaviour of 61 adult females observed for 13 270 h to test several mechanistic hypotheses of social ageing and evaluated the consistency between patterns from mixed-longitudinal and within-individual analyses. With advancing age, females reduced the size of their social network, which could not be explained by an overall increase in the time spent alone, but by an age-related decline in mostly active, but also passive, behaviour, best demonstrated by within-individual analyses. A selective tendency to approach preferred partners was maintained into old age but did not increase. Our results contribute to our understanding of the driver of social ageing in natural animal populations and suggest that social disengagement and selectivity follow independent trajectories during ageing.

Neural attentional filters and behavioural outcome follow independent individual trajectories over the adult lifespan.

Preserved communication abilities promote healthy ageing. To this end, the age-typical loss of sensory acuity might in part be compensated for by an individual's preserved attentional neural filtering. Is such a compensatory brain-behaviour link longitudinally stable? Can it predict individual change in listening behaviour? We here show that individual listening behaviour and neural filtering ability follow largely independent developmental trajectories modelling electroencephalographic and behavioural data of N = 105 ageing individuals (39-82 y). First, despite the expected decline in hearing-threshold-derived sensory acuity, listening-task performance proved stable over 2 y. Second, neural filtering and behaviour were correlated only within each separate measurement timepoint (T1, T2). Longitudinally, however, our results raise caution on attention-guided neural filtering metrics as predictors of individual trajectories in listening behaviour: neither neural filtering at T1 nor its 2-year change could predict individual 2-year behavioural change, under a combination of modelling strategies.

Neural attentional filters and behavioural outcome follow independent individual trajectories over the adult lifespan

Preserved communication abilities promote healthy ageing. To this end, the age-typical loss of sensory acuity might in part be compensated for by an individual’s preserved attentional neural filtering. Is such a compensatory brain–behaviour link longitudinally stable? Can it predict individual change in listening behaviour? We here show that individual listening behaviour and neural filtering ability follow largely independent developmental trajectories modelling electroencephalographic and behavioural data of N = 105 ageing individuals (39–82 y). First, despite the expected decline in hearing-threshold-derived sensory acuity, listening-task performance proved stable over 2 y. Second, neural filtering and behaviour were correlated only within each separate measurement timepoint (T1, T2). Longitudinally, however, our results raise caution on attention-guided neural filtering metrics as predictors of individual trajectories in listening behaviour: neither neural filtering at T1 nor its 2-year change could predict individual 2-year behavioural change, under a combination of modelling strategies.

Play Behavior Varies with Age, Sex, and Socioecological Context in Wild, Immature Orangutans (Pongo spp.)

Play is thought to serve different purposes at different times during ontogeny. The nature and frequency of play are expected to change accordingly over the developmental trajectory and with socio-ecological context. Orangutans offer the opportunity to disentangle the ontogenetic trajectories of solitary and social play with their extended immature phase, and socio-ecological variation among populations and species. We evaluated the frequency of play in 39 immature individuals across two populations (Pongo pygmaeus wurmbii, at Tuanan, Borneo, and P. abelii at Suaq, Sumatra), age (0–11 years), sex, and social context, using more than 11 500 h of full-day focal observation data. We found independent age trajectories of different play types, with solitary object and solitary locomotor peaking before social play. Social play partners changed during ontogeny, and male immatures were more likely to engage in non-mother social play than females. Overall, social play was more frequent at Suaq than Tuanan, linked to the more frequent availability of partners. Furthermore, per time in association with conspecifics, Tuanan immatures were as likely to engage in social play as their peers at Suaq, suggesting similar intrinsic motivation. Increasing fruit availability correlated with both longer associations and increased social play frequency in the less sociable population of Tuanan, but not at Suaq. Our findings on orangutans support evidence from other species that different play types follow different developmental trajectories, vary with sex, social opportunities, and ecological context. Although drawing functional inferences is challenging, the distinct developmental trajectories reflecting adult sociability and behavioral repertoires may indicate that play serves several, non-mutually exclusive functions during ontogeny.

Nonadiabatic Field on Quantum Phase Space: A Century after Ehrenfest.

Nonadiabatic transition dynamics lies at the core of many electron/hole transfer, photoactivated, and vacuum field-coupled processes. About a century after Ehrenfest proposed "Phasenraum" and the Ehrenfest theorem, we report a conceptually novel trajectory-based nonadiabatic dynamics approach, nonadiabatic field (NAF), based on a generalized exact coordinate-momentum phase space formulation of quantum mechanics. It does not employ the conventional Born-Oppenheimer or Ehrenfest trajectory in the nonadiabatic coupling region. Instead, in NAF the equations of motion of the independent trajectory involve a nonadiabatic nuclear force term in addition to an adiabatic nuclear force term of a single electronic state. A few benchmark tests for gas phase and condensed phase systems indicate that NAF offers a practical tool to capture the correct correlation of electronic and nuclear dynamics for processes where the states remain coupled all the time as well as for the asymptotic region where the coupling of electronic states vanishes.

SARS-CoV-2 infection in immunosuppression evolves sub-lineages which independently accumulate neutralization escape mutations.

One mechanism of variant formation may be evolution during long-term infection in immunosuppressed people. To understand the viral phenotypes evolved during such infection, we tested SARS-CoV-2 viruses evolved from an ancestral B.1 lineage infection lasting over 190 days post-diagnosis in an advanced HIV disease immunosuppressed individual. Sequence and phylogenetic analysis showed two evolving sub-lineages, with the second sub-lineage replacing the first sub-lineage in a seeming evolutionary sweep. Each sub-lineage independently evolved escape from neutralizing antibodies. The most evolved virus for the first sub-lineage (isolated day 34) and the second sub-lineage (isolated day 190) showed similar escape from ancestral SARS-CoV-2 and Delta-variant infection elicited neutralizing immunity despite having no spike mutations in common relative to the B.1 lineage. The day 190 isolate also evolved higher cell-cell fusion and faster viral replication and caused more cell death relative to virus isolated soon after diagnosis, though cell death was similar to day 34 first sub-lineage virus. These data show that SARS-CoV-2 strains in prolonged infection in a single individual can follow independent evolutionary trajectories which lead to neutralization escape and other changes in viral properties.

Serial attentional resource allocation during parallel feature value tracking.

The visual system has evolved the ability to track features like color and orientation in parallel. This property aligns with the specialization of processing these feature dimensions in the visual cortex. But what if we ask to track changing feature-values within the same feature dimension? Parallel tracking would then have to share the same cortical representation, which would set strong limitations on tracking performance. We address this question by measuring the precision of color representations when human observers track the color of two superimposed dot clouds that simultaneously change color along independent trajectories in color-space. We find that tracking precision is highly imbalanced between streams and that tracking precision changes over time by alternating between streams at a rate of ~1 Hz. These observations suggest that, while parallel color tracking is possible, it is highly limited, essentially allowing for only one color-stream to be tracked with precision at a given time.

Independent and joint trajectories of depression and anxiety symptoms among Chinese male sailors throughout a prolonged non-24-h rotating shift schedule at sea: a parallel-process growth mixture modeling approach

BackgroundThe predictive and protective effect of hardiness on mental health remains unclear among shift workers on non-24-h working schedules. The present study aimed to investigate the independent and joint trajectories of depression and anxiety symptoms and the role of hardiness during a prolonged period of non-24-h shift working schedule.MethodsFour hundred nine Chinese male sailors (working on 18-h watchstanding schedule) were recruited and completed all 5-wave tests through online questionnaires (at Day 1, 14, 28, 42, 55, respectively) during a 55-day sailing. The questionnaires included sociodemographic variables, hardiness, depression and anxiety symptoms. Independent and joint trajectories of depression and anxiety symptoms were estimated by latent growth mixture models. The effect of hardiness on trajectories was examined by logistic regression models.Results2 and 3 latent trajectories were identified for depression and anxiety symptoms, respectively. Based on initial levels and development trends, 3 distinct joint trajectories of depression and anxiety were identifed and named as: “Low-Inverted U” group (73.6%), “Moderate-Deterioration” group (6.9%), and “High-Stable” group (9.5%). Sailors with higher levels of hardiness were more likely to follow the “Low-Inverted U” trajectory of depression and anxiety symptoms (all p < 0.001).ConclusionsThere existed individual differences in the trajectories of depression and anxiety. Hardiness may have a protective effect that can prevent and alleviate depression and anxiety symptoms. Therefore, hardiness-based intervention programs are encouraged among the shift workers on non-24-h working and rest schedules.