Common practices in detecting psychological early warning signals may lead to incorrect results

The past few years have seen a rapid growth in research on early warning signals (EWSs) in psychological systems. Whereas early studies showed that EWSs are associated with sudden changes in clinical change trajectories, later findings showed that EWSs may not be general and have low predictive power. In this study, we demonstrate that two common practices in psychological EWS studies are not warranted by theories and may lead to false-negative or false-positive results, explaining the mixed findings in the literature. These two practices are (1) using loosely-defined time windows for early warning indicators and (2) using different variables for detecting transitions and calculating early warning indicators. We first review the theoretical background of EWSs and current research practices for EWS studies. Two simulation studies with different types of system changes are used to demonstrate the possible consequences of the two practices. In Study 1, we show that when the time window for early warning indicators is not strictly before the transition, the transition process itself and the system dynamics after the transition may confound the result. In Study 2, we show that when the transition and early warning indicators are measured from different variables in the same system, the predictive relationship may not exist. Based on our findings, we provide suggestions for future EWS studies in terms of theory construction, study design, and data analysis

Magnetic fluctuations and superconducting properties of CaKFe4As4 studied by 75As NMR

We report $^{75}$As nuclear magnetic resonance (NMR) studies on a new iron-based superconductor CaKFe$_4$As$_4$ with $T_{\rm c}$ = 35 K. $^{75}$As NMR spectra show two distinct lines corresponding to the As(1) and As(2) sites close to the K and Ca layers, respectively, revealing that K and Ca layers are well ordered without site inversions. We found that nuclear quadrupole frequencies $\nu_{\rm Q}$ of the As(1) and As(2) sites show an opposite temperature ($T$) dependence. Nearly $T$ independent behavior of the Knight shifts $K$ are observed in the normal state, and a sudden decrease in $K$ in the superconducting (SC) state clearly evidences spin-singlet Cooper pairs. $^{75}$As spin-lattice relaxation rates 1/$T_1$ show a power law $T$ dependence with different exponents for the two As sites. The isotropic antiferromagnetic spin fluctuations characterized by the wavevector ${\bf q}$ = ($\pi$, 0) or (0, $\pi$) in the single-iron Brillouin zone notation are revealed by 1/$T_1T$ and $K$ measurements. Such magnetic fluctuations are necessary to explain the observed temperature dependence of the $^{75}$As quadrupole frequencies, as evidenced by our first-principles calculations. In the SC state, 1/$T_1$ shows a rapid decrease below $T_{\rm c}$ without a Hebel-Slichter peak and decreases exponentially at low $T$, consistent with an $s^{\pm}$ nodeless two-gap superconductor.Comment: 9 pages, 6 figures, accepted for publication in Phys.Rev.

Prospects for studying the mass and gas in protoclusters with future CMB observations

Protoclusters are the progenitors of massive galaxy clusters. Understanding the properties of these structures is important for building a complete picture of cluster formation and for understanding the impact of environment on galaxy evolution. Future cosmic microwave background (CMB) surveys may provide insight into the properties of protoclusters via observations of the thermal Sunyaev Zel'dovich (SZ) effect and gravitational lensing. Using realistic hydrodynamical simulations of protoclusters from the Three Hundred Project, we forecast the ability of CMB Stage 4-like (CMB-S4) experiments to detect and characterize protoclusters with observations of these two signals. For protoclusters that are the progenitors of clusters at $z = 0$ with $M_{200c} \gtrsim 10^{15}\,M_{\odot}$ we find that the S4-Ultra deep survey has a roughly 20% chance of detecting the main halos in these structures with ${\rm SNR} > 5$ at $z \sim 2$ and a 10% chance of detecting them at $z \sim 2.5$, where these probabilities include the impacts of noise, CMB foregrounds, and the different possible evolutionary histories of the structures. On the other hand, if protoclusters can be identified using alternative means, such as via galaxy surveys like LSST and Euclid, CMB-S4 will be able to obtain high signal-to-noise measurements of their stacked lensing and SZ signals, providing a way to measure their average mass and gas content. With a sample of 2700 protoclusters at $z = 3$, the CMB-S4 wide survey can measure the stacked SZ signal with a signal-to-noise of 7.2, and the stacked lensing signal with a signal-to-noise of 5.7. Future CMB surveys thus offer exciting prospects for understanding the properties of protoclusters.Comment: 12 pages, 10 figure

Genetic Regulation of Myofiber Hypertrophy?

Introduction. Progressive, resistance exercise training (RT) induces skeletal muscle hypertrophy, increases strength, power, and quality of muscle, and is potentially the most promising method to regenerate and re-grow muscle in populations suffering from involuntary atrophy. However, we have previously shown that there is a large degree of intersubject variability for myofiber hypertrophy in response to RT with adults having no response [-16μm2 (mean myofiber growth), Non], a modest response (1111μm2, Mod), or an extreme hypertrophic response (2475μm2, Xtr). Underlying mechanisms for this differential growth response are largely unknown. Therefore, the purpose of this study was to determine whether differences in the skeletal muscle transcriptome exist among the three response clusters, prior to 16 weeks of RT. Methods. mRNA was isolated from muscle biopsies taken from the vastus lateralis of 44 previously clustered men and women (aged 19-75y). Agilent 4X44K single color genechips were used to determine differences in skeletal muscle gene expression among the three response clusters. Ingenuity Pathways Analysis (IPA) and available Gene Ontology were used for functional annotation of differentially expressed genes and identification of informative genes that may instigate the observed myofiber growth phenotypes. Results. After removing genes with low signal intensities and normalizing the data, we identified substantial differences in the transcript profile among the response clusters with the most notable differences between the Xtr- and Non-responders. 8026 differentially expressed genes were identified between Xtr vs. Non, 2463 between Xtr vs. Mod, and 1294 between Mod vs. Non. There were 1632 genes with expression specific to the Xtr (i.e. differences existed between Xtr vs. Non and Mod, but not between the Non vs. Mod) and 617 genes with expression specific to the Non. Functional classification, with IPA, identified Skeletal Muscle System Development and Function (SMSDF) as a top functional category containing a significant number of differentially expressed genes (p\u3c0.05) in all three comparisons. SMSDF was also a top five functional category for the genes specific to both Xtr and Non (p\u3c0.05). Within the broad SMSDF category, IPA defined sub-categories of functional annotation, which allowed us to further interpret the differentially expressed genes. We have highlighted several genes that primarily had expression specific to the Xtr or had increased expression from Non to Mod to Xtr. Highlighted genes are involved with satellite cell activation and function (SOX8, HGF, PAX7), differentiation (MYOD1, MYOG, APOE, TRIO, MSTN), skeletal muscle growth (DGKZ, ESR1, OXT, OXTR, UCN2, GREB1), modulation of inflammation and fuel utilization (PYY), and improved function (TFAM, UCN2, CRHR1, CRHR2). Additionally, there was a decrease in expression (Xtr vs. Non) for several genes involved with modulation of inflammation and fuel utilization (AEBP1, NFKB1, CD36, AIF1). Discussion. These results indicate that differences in gene expression do exist among the response clusters prior to mechanically induced hypertrophy and that the Xtr-responders were “primed” to respond. We identified several genes and signaling pathways that may promote or inhibit muscle growth and thus, initiate the three observed hypertrophic response phenotypes. Results from this study enabled us to identify distinctive molecular pathways, particularly between the Xtr- and Non-responders, for development of targeted interventions. Further research is necessary to determine which of these genes or networks of genes truly distinguish load mediated hypertrophy potential

simlandr:Simulation-Based Landscape Construction for Dynamical Systems

We present the simlandr package for R, which provides a set of tools for constructing potential landscapes for dynamic systems using Monte Carlo simulation. Potential landscapes can be used to quantify the stability of system states. While the canonical form of a potential function is defined for gradient systems, generalized potential functions can also be defined for non-gradient dynamical systems. Our method is based on the potential landscape definition by Wang, Xu, and Wang (2008), and can be used for a large variety of models. Using two multistable dynamical systems as examples, we illustrate how simlandr can be used for model simulation, landscape construction, and barrier height calculation

From metaphor to computation:Constructing the potential landscape for multivariate psychological formal models

For psychological formal models, the stability of different phases is an important property for understanding individual differences and change processes. Many researchers use landscapes as a metaphor to illustrate the concept of stability, but so far there is no method to quantify the stability of a system’s phases. We here propose a method to construct the potential landscape for multivariate psychological models. This method is based on the generalized potential function defined by Wang et al. (2008) and Monte Carlo simulation. Based on potential landscapes we define three different types of stability for psychological phases: absolute stability, relative stability, and geometric stability. The panic disorder model by Robinaugh et al. (2019) is used as an example, to demonstrate how the method can be used to quantify the stability of states and phases, illustrate the influence of model parameters, and guide model modifications. An R package, simlandr, was developed to provide an implementation of the method

Conversational ontology operator: Patient-centric vaccine dialogue management engine for spoken conversational agents

BACKGROUND: Previously, we introduced our Patient Health Information Dialogue Ontology (PHIDO) that manages the dialogue and contextual information of the session between an agent and a health consumer. In this study, we take the next step and introduce the Conversational Ontology Operator (COO), the software engine harnessing PHIDO. We also developed a question-answering subsystem called Frankenstein Ontology Question-Answering for User-centric Systems (FOQUS) to support the dialogue interaction. METHODS: We tested both the dialogue engine and the question-answering system using application-based competency questions and questions furnished from our previous Wizard of OZ simulation trials. RESULTS: Our results revealed that the dialogue engine is able to perform the core tasks of communicating health information and conversational flow. Inter-rater agreement and accuracy scores among four reviewers indicated perceived, acceptable responses to the questions asked by participants from the simulation studies, yet the composition of the responses was deemed mediocre by our evaluators. CONCLUSIONS: Overall, we present some preliminary evidence of a functioning ontology-based system to manage dialogue and consumer questions. Future plans for this work will involve deploying this system in a speech-enabled agent to assess its usage with potential health consumer users

Optimizing Partial Power Processing for Second-Use Battery Energy Storage Systems

Repurposing automotive batteries to second-use battery energy storage systems (2-BESS) may have environmental and economic benefits. The challenge with second-use batteries is the uncertainty and diversity of the expected packs in terms of their chemistry, capacity and remaining useful life. This paper introduces a new strategy to optimize 2-BESS performance despite the diversity or heterogeneity of individual batteries while reducing the cost of power conversion. In this paper, the statistical distribution of the power heterogeneity in the supply of batteries is considered when optimizing the choice of power converters and designing the power flow within the battery energy storage system (BESS) to maximize battery utilization. By leveraging a new lite-sparse hierarchical partial power processing (LS-HiPPP) approach, we show a hierarchy in partial power processing (PPP) partitions power converters to a) significantly reduce converter ratings, b) process less power to achieve high system efficiency with lower cost (lower efficiency) converters, and c) take advantage of economies of scale by requiring only a minimal number of sets of identical converters. The results demonstrate that LS-HiPPP architectures offer the best tradeoff between battery utilization and converter cost and had higher system efficiency than conventional partial power processing (C-PPP) in all cases

Termination of related and unrelated joint ventures: a contingency approach

Previous research has investigated various factors that influence joint venture (JV) termination. Yet the majority of studies do not distinguish between different types of JVs, particularly whether a JV is related or unrelated to the parent firm. Due to their inherent differences, related and unrelated JVs are likely to evolve distinctly, and their tendency to terminate may also differ under various conditions. This study takes a contingency approach and argues the impact of various factors on JV termination depends upon JV relatedness. An event history analysis finds increases in environmental uncertainty and higher resource complementarity reduce the likelihood that a firm will terminate unrelated JVs as compared to related JVs. Conversely parent firm performance and wider JV scope increase the likelihood that the firm will terminate unrelated JVs as compared to related JVs. The findings suggest the need to consider JV relatedness in understanding JV evolution and termination