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Abstract Background 18-Fluoro-deoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) is a valuable imaging tool widely used in the management of cancer patients. Deep learning models excel at segmenting highly metabolic tumors but face challenges in regions with complex anatomy and normal cell uptake, such as the gastro-intestinal tract. Despite these challenges, it remains important to achieve accurate segmentation of gastro-intestinal tumors. Methods Here, we present an international multicenter comparative study between a novel organ-focused approach and a whole-body training method to evaluate the effectiveness of training data homogeneity in accurately identifying gastro-intestinal tumors. In the organ-focused method, the training data is limited to cases with intestinal tumors which makes the network trained with more homogeneous data and with stronger presence of intestinal tumor signals. The whole body approach extracts the intestinal tumors from the results of a model trained on the whole-body scans. Both approaches were trained using diffuse large B cell (DLBCL) patients from a large multi-center clinical trial (NCT01287741). Results We report an improved mean(±std) Dice score of 0.78(±0.21) for the organ-based approach on the hold-out set, compared to 0.63(±0.30) for the whole-body approach, with the p-value of less than 0.0001. At the lesion level, the proposed organ-based approach also shows increased precision, recall, and F1-score. An independent trial was used to evaluate the generalizability of the proposed method to non-Hodgkin’s lymphoma (NHL) patients with follicular lymphoma (FL). Conclusion Given the variability in structure and metabolism across tissues in the body, our quantitative findings suggest organ-focused training enhances intestinal tumor segmentation by leveraging tissue homogeneity in the training data, contrasting with the whole-body training approach, which, by its very nature, is a more heterogeneous data set.

The critical micelle concentration (CMC) is a crucial parameter in understanding the self-assembly behavior of surfactants. In this study, we combine simulation and experiment to demonstrate the predictive capability of molecularly informed field theories in estimating the CMC of biologically based protein surfactants. Our simulation approach combines the relative entropy coarse-graining of small-scale atomistic simulations with large-scale field-theoretic simulations, allowing us to efficiently compute the free energy of micelle formation necessary for the CMC calculation while preserving chemistry-specific information about the underlying surfactant building blocks. We apply this methodology to a unique intrinsically disordered protein platform capable of a wide variety of tailored sequences that enable tunable micelle self-assembly. The computational predictions of the CMC closely match experimental measurements, demonstrating the potential of molecularly informed field theories as a valuable tool to investigate self-assembly in bio-based macromolecules systematically.

We study a binary blend of telechelic homopolymers that can form reversible AB-type bonds at the chain ends. Reversibly bonding polymers display novel material properties, including thermal tunability and self-healing, that are not found in conventional covalently bonded polymers. Previous studies of reversibly bonding polymer systems have been limited by the computational demand of accounting for an infinite number of possible reaction products in a spatially inhomogeneous, self-assembled structure. We demonstrate that newly developed theoretical models and numerical methods enable the simultaneous computation of phase equilibrium, reaction equilibrium, and self-assembly via self-consistent field theory. Phase diagrams are computed at a variety of physically relevant conditions and are compared with nonreactive analogues as well as previous experimental studies of telechelic polymer blends.

The promise of ABC triblock terpolymers for improving the mechanical properties of thermoplastic elastomers is demonstrated by comparison with symmetric ABA/CBC analogs having similar molecular weights and volume fraction of B and A/C domains. The ABC architecture enhances elasticity (up to 98% recovery over 10 cycles) in part through essentially full chain bridging between discrete hard domains leading to the minimization of mechanically unproductive loops. In addition, the unique phase space of ABC triblocks also enables the fraction of hard-block domains to be higher (fhard ≈ 0.4) while maintaining elasticity, which is traditionally only possible with non-linear architectures or highly asymmetric ABA triblock copolymers. These advantages of ABC triblock terpolymers provide a tunable platform to create materials with practical applications while improving our fundamental understanding of chain conformation and structure-property relationships in block copolymers.

OBJECTIVE: Individual differences in attachment insecurity can have important implications for experiences of positive emotions. However, existing research on the link between attachment insecurity and positive emotional experiences has typically used a composite measure of positive emotions, overlooking the potential importance of differentiating discrete emotions. METHOD: We conducted a meta-analysis of 10 cross-sectional samples (N = 3215), examining how attachment insecurity is associated with self-reported frequency of experiencing positive emotions, with a distinction made between more social (i.e., love and gratitude) and less social (i.e., peace and awe or curiosity) positive emotions. RESULTS: High (vs. low) levels of both attachment anxiety and avoidance were associated with less frequent experience of positive emotions regardless of their social relevance. When analyzing each emotion separately, we found that attachment anxiety showed negative relations to all emotions except gratitude. Attachment avoidance was negatively associated with all emotions, and the link was even stronger with love (vs. peace, awe, or curiosity). Additional analyses of daily diary data revealed that attachment anxiety and avoidance were also negatively associated with daily experiences of positive emotions, regardless of social relevance. CONCLUSION: Our results underscore the need to further investigate the mechanisms underlying insecure individuals blunted positive emotional experiences.

A correct understanding of passive force-deflection response is important for lateral load evaluations of bridges during extreme events such as earthquakes and from thermal expansion and contraction of the superstructure. In these cases, the ultimate passive force is highly sensitive to the interface friction between the abutment wall and the adjacent geomaterials. These geomaterials may simply consist of compacted sand or gravel; however, for geosynthetic reinforced soil (GRS) backfill a geosynthetic fabric may be placed between the abutment wall and soil which can reduce the interface friction. In still other cases, a zone of compressible material such as geofoam may be used as a barrier between the soil and abutment to reduce lateral earth pressures. To evaluate the effect of the interface friction on passive force-deflection curves, large-scale testing was performed with a test abutment that was 3.35 m wide and 1.68 m high. Backfill materials consisted of sand, gravel, GRS backfill, and a geofoam inclusion between a sand backfill and the abutment. As a result of lower interface friction, the GRS backfills only developed 80% of the force developed by the unreinforced gravel. The geofoam inclusion decreased the passive force by about 70% as a result of reduced interface friction.

This qualitative study at the University of Minnesota--Twin Cities, USA, investigated leader identity emergence of study group facilitators. There is a gap in the professional literature regarding study group programs and identity emergence of the student paraprofessionals who facilitate the study sessions. This study built upon previous studies of identity formation by integrating educational theories that help explain the changes that occurred. Peer study group programs are powerful co-curricular experiences. This study provided answers to "why" and "how" identity emergence occurs. The Leader Identity Development Model for peer study group facilitators was developed based on the findings from this study and other experiences with study group leaders over the past three decades by David Arendale to help predict this change and the experiences that supported identity formation. Among those catalysts were written reflections by the study group leaders throughout the academic term on what they learned about themselves and about their conversations with other study leaders and the study group program manager. Implications are provided that explain how peer programs can become a more transformative learning ecosystem. Peer learning programs present an untapped personal and professional development opportunity for student leaders that would be even more powerful if it were intentional rather than serendipitous.

Water structure and dynamics can be key modulators of adsorption, separations, and reactions at soft material interfaces, but systematically tuning water environments in an aqueous, accessible, and functionalizable material platform has been elusive. This work leverages variations in excluded volume to control and measure water diffusivity as a function of position within polymeric micelles using Overhauser dynamic nuclear polarization spectroscopy. Specifically, a versatile materials platform consisting of sequence-defined polypeptoids simultaneously offers a route to controlling the functional group position and a unique opportunity to generate a water diffusivity gradient extending away from the polymer micelle core. These results demonstrate an avenue not only to rationally design the chemical and structural properties of polymer surfaces but also to design and tune the local water dynamics that, in turn, can adjust the local activity for solutes.

This qualitative study investigated high school student peer counselors' experience of a mind-body medicine curriculum incorporated into a peer counseling program following a school shooting. A series of focus groups were held with peer counselors in 10th-12th grade (n = 24, mean age = 16.5 [SD = 1.0]; 71% female) participating in the mind-body medicine curriculum. Data analysis was conducted using a thematic analysis. Peer counselors reported that the mind-body medicine curriculum decreased their stress and helped them regulate their emotions. Other interview themes included feeling closer to other students, improved relationships with their parents, increased resilience and self-confidence, working harder for their goals, not stressing over small things, and choosing supportive friends. The themes related to their peer counseling work were that the mind-body skills would help them be less reactive and more patient with other students and that the skills would also be helpful for these other students. This study has important implications for practitioners in the schools because the mind-body medicine curriculum can effectively complement the communication, problem-solving, and decision-making skills taught in peer counseling programs.

Abstract BackgroundYoung adults (ages 18‐39 years) with cancer face unique risks for negative psychosocial outcomes. These risks could be lessened with positive psychology interventions adapted for social media if intervention messages encourage intentions to do the activities and positive message reactions and if young adults with cancer perceive few downsides. ObjectiveThis study aimed to assess whether social media messages from evidence-based positive psychology interventions encouraged intentions to do the intervention activities and intended positive message reactions, overall and among sociodemographic or cancer characteristic subgroups. We also aimed to identify perceived downsides of the activity that would negatively impact the interventions’ feasibility. MethodsYoung adults (ages 18‐39 years, cancer diagnosis ages 15‐39 years) were randomized to a between-persons web-based experiment. Participants viewed a social media message with social context cues (vs not) for 1 of 2 types of intervention (acts of kindness vs social connectedness). Participants reported intentions to do the activity, along with their perceived social presence in the message (how much they felt the sense of others) and forecasted positivity resonance (whether they would experience socially connected positive emotions when doing the activity), with 5-point items. Participants also reported their self-efficacy (how certain they can do the intervention activity) with a 0‐100 item and potential downsides of the activity categorically. ResultsMore than 4 out of 5 young adults with cancer (N=396) reported they “somewhat” (coded as 3) to “extremely” (5) intended to do the intervention activity (336/396, 84.8%; mean ranged from 3.4‐3.6, SD 0.9-1.0), perceived social presence in the messages (350/396, 88.4%; mean 3.8, SD 0.7), and forecasted positivity resonance (349/396, 88.1%; mean 3.8‐3.9, SD 0.8). Participants reported having self-efficacy to complete the activity (mean 70.7% of possible 100%, SD 15.4%‐17.2%). Most (320/396, 80.8%) did not think of the downsides of the interventions. Messages with social context cues (vs not) and both intervention types were rated similarly (all PPP ConclusionsPositive psychology intervention messages adapted for social media were perceived as acceptable and feasible among young adults with cancer. The social media–based messages encouraged increasing one’s social connectedness and performing acts of kindness. Young adults with cancer also predicted they would have feelings of positive social engagement (positivity resonance) when doing the interventions—the key ingredient for experiencing the health benefits of these activities. This study provides promising evidence for the development of age-appropriate, highly scalable interventions to improve psychosocial health among young adults with cancer.

Abstract We present observations from two field deployments of a calibrated tiltmeter that we name the Self‐Calibrating Tilt Accelerometer (SCTA). The tiltmeter is based upon a triaxial quartz crystal accelerometer; the horizontal channels measure tilt and are periodically rotated into the vertical to obtain a measurement of the acceleration of gravity. Changes in the measured total acceleration are ascribed to drift in the vertical channel and used as calibrations for removing that same drift from the tilt time series observed between calibrations. Changes in the span (sensitivity) of the accelerometer channels can also be measured by calibrating them pointing up and down. A 3‐year test on the seafloor at Axial Seamount show that the calibrations are consistent with a linear‐exponential model of drift to a RMS residual of ∼0.5 μg (μrad). The calibrated tilt time series was impacted by platform settling for the first 2 years, but after repositioning the tiltmeter, the calibrated observations were consistent for the final year with the tilt observed on a nearby LILY tiltmeter, within an assumed level of drift for the unconstrained LILY sensor. A separate 15‐month test in a stable vault at Piñon Flat Observatory was complicated by seasonal temperature variations of >5°C; the calibrations are consistent with a linear‐exponential model of drift to ∼2 μg RMS when temperature and temperature time‐derivative dependence is included. Similarly, the calibrated tilt time series was impacted by thermal deformation of the SCTA assembly. A future test in a thermally and tectonically stable borehole will be required to assess the accuracy of the SCTA.

Field-theoretic simulations are numerical methods for polymer field theory, which include fluctuation corrections beyond the mean-field level, successfully capturing various mesoscopic phenomena. Most field-theoretic simulations of polymeric fluids use the auxiliary field (AF) theory framework, which employs Hubbard–Stratonovich transformations for the particle-to-field conversion. Nonetheless, the Hubbard–Stratonovich transformation imposes significant limitations on the functional form of the non-bonded potentials. Removing this restriction on the non-bonded potentials will enable studies of a wide range of systems that require multi-body or more complex potentials. An alternative representation is the hybrid density-explicit auxiliary field theory (DE-AF), which retains both a density field and a conjugate auxiliary field for each species. While the DE-AF representation is not new, density-explicit field-theoretic simulations have yet to be developed. A major challenge is preserving the real and non-negative nature of the density field during stochastic evolution. To address this, we introduce positivity-preserving schemes that enable the first stable and efficient density-explicit field-theoretic simulations (DE-AF FTS). By applying the new method to a simple fluid, we find thermodynamically correct results at high densities, but the algorithm fails in the dilute regime. Nonetheless, DE-AF FTS is shown to be broadly applicable to dense fluid systems including a simple fluid with a three-body non-bonded potential, a homopolymer solution, and a diblock copolymer melt. [ABSTRACT FROM AUTHOR]

Transport of ions through solid polymeric electrolytes (SPEs) involves a complicated interplay of ion solvation, ion-ion interactions, ion-polymer interactions, and free volume. Nonetheless, prevailing viewpoints on the subject promote a significantly simplified picture, likening ion transport in a polymer to that in an unstructured fluid at low solute concentrations. Although this idealized liquid transport model has been successful in guiding the design of homogeneous electrolytes, structured electrolytes provide a promising alternate route to achieve high ionic conductivity and selectivity. In this perspective, we begin by describing the physical origins of the idealized liquid transport mechanism and then proceed to examine known cases of decoupling between the matrix dynamics and ionic transport in SPEs. Specifically we discuss conditions for "decoupled" mobility that include a highly polar electrolyte environment, a percolated path of free volume elements (either through structured or unstructured channels), high ion concentrations, and labile ion-electrolyte interactions. Finally, we proceed to reflect on the potential of these mechanisms to promote multivalent ion conductivity and the need for research into the interfacial properties of solid polymer electrolytes as well as their performance at elevated potentials.

The Positivity Resonance Theory of coexperienced positive affect describes moments of interpersonal connection characterized by shared positive affect, caring nonverbal synchrony, and biological synchrony. The construct validity of positivity resonance and its longitudinal associations with health have not been tested. The current longitudinal study examined whether positivity resonance in conflict interactions between 154 married couples predicts health trajectories over 13 years and longevity over 30 years. We used couples' continuous ratings of affect during the interactions to capture coexperienced positive affect and continuous physiological responses to capture biological synchrony between spouses. Video recordings were behaviorally coded for coexpressed positive affect, synchronous nonverbal affiliation cues (SNAC), and behavioral indicators of positivity resonance (BIPR). To evaluate construct validity, we conducted a confirmatory factor analysis to test a latent factor of positivity resonance encompassing coexperienced positive affect, coexpressed positive affect, physiological linkage of interbeat heart intervals, SNAC, and BIPR. The model showed excellent fit. To evaluate associations with health and longevity, we used dyadic latent growth curve modeling and Cox proportional hazards modeling, respectively, and found that greater latent positivity resonance predicted less steep declines in health and increased longevity. Associations were robust when accounting for initial health symptoms, sociodemographic characteristics, health-related behaviors, and individually experienced positive affect. We repeated health and longevity analyses, replacing latent positivity resonance with BIPR, and found consistent results. Findings validate positivity resonance as a multimodal construct, support the utility of the BIPR measure, and provide initial evidence for the characterization of positivity resonance as a positive health behavior. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

The small specific entropy of mixing of high molecular weight polymers implies that most blends of dissimilar polymers are immiscible with poor physical properties. Historically, a wide range of compatibilization strategies have been pursued, including the addition of copolymers or emulsifiers or installing complementary reactive groups that can promote the in situ formation of block or graft copolymers during blending operations. Typically, such reactive blending exploits reversible or irreversible covalent or hydrogen bonds to produce the desired copolymer, but there are other options. Here, we argue that ionic bonds and electrostatic correlations represent an underutilized tool for polymer compatibilization and in tailoring materials for applications ranging from sustainable polymer alloys to organic electronics and solid polymer electrolytes. The theoretical basis for ionic compatibilization is surveyed and placed in the context of existing experimental literature and emerging classes of functional polymer materials. We conclude with a perspective on how electrostatic interactions might be exploited in plastic waste upcycling.

Motivated by collective emotions theories that propose emotions shared between individuals predict group-level qualities, we hypothesized that co-experienced affect during interactions is associated with relationship quality, above and beyond the effects of individually experienced affect. Consistent with positivity resonance theory, we also hypothesized that co-experienced positive affect would have a stronger association with relationship quality than would co-experienced negative affect. We tested these hypotheses in 150 married couples across 3 conversational interactions: a conflict, a neutral topic, and a pleasant topic. Spouses continuously rated their individual affective experience during each conversation while watching video-recordings of their interactions. These individual affect ratings were used to determine, for positive and negative affect separately, the number of seconds of co-experienced affect and individually experienced affect during each conversation. In line with hypotheses, results from all 3 conversational topics suggest that more co-experienced positive affect is associated with greater marital quality, whereas more co-experienced negative affect is associated with worse marital quality. Individual level affect factors added little explanatory value beyond co-experienced affect. Comparing co-experienced positive affect and co-experienced negative affect, we found that co-experienced positive affect generally outperformed co-experienced negative affect, although co-experienced negative affect was especially diagnostic during the pleasant conversational topic. Findings suggest that co-experienced positive affect may be an integral component of high-quality relationships and highlight the power of co-experienced affect for individual perceptions of relationship quality. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Introduction: Influenza vaccines are commonly provided through community health events and primary care appointments. However, acute unscheduled healthcare visits such as emergency department (ED) visits are increasingly viewed as important vaccination opportunities. Emergency departments may be well-positioned to complement broader public health efforts with integrated vaccination programs.  Methods: We studied an ED-based influenza vaccination initiative in an urban hospital and examined patient-level factors associated with screening and vaccination uptake. Our analyses included patient visits to the ED from October 1, 2019-April 1, 2020. Results: The influenza screening and vaccination program proved feasible. Of the 20,878 ED visits that occurred within the study period, 3,565 (17.1%) included a screening for influenza vaccine eligibility; a small proportion (11.5%) of the patients seen had multiple screenings. Among the patients screened eligible for the vaccine, 916 ultimately received an influenza vaccination while in the ED (43.7% of eligible patients). There was significant variability in the characteristics of patients who were and were not screened and vaccinated. Age, gender, race, preferred language, and receipt of a flu vaccine in prior years were associated with screening and/or receiving a vaccine in the ED.  Conclusion: Vaccination programs in the ED can boost community vaccination rates and play a role in both preventing and treating current and future vaccine-preventable public health crises, although efforts must be made to deliver services equitably.

Free energy evaluation in molecular simulations of both classical and quantum systems is computationally intensive and requires sophisticated algorithms. This is because free energy depends on the volume of accessible phase space, a quantity that is inextricably linked to the integration measure in a coordinate representation of a many-body problem. In contrast, the same problem expressed as a field theory (auxiliary field or coherent states) isolates the particle number as a simple parameter in the Hamiltonian or action functional and enables the identification of a chemical potential field operator. We show that this feature leads a “direct” method of free energy evaluation, in which a particle model is converted to a field theory and appropriate field operators are averaged using a field-theoretic simulation conducted with complex Langevin sampling. These averages provide an immediate estimate of the Helmholtz free energy in the canonical ensemble and the entropy in the microcanonical ensemble. The method is illustrated for a classical polymer solution, a block copolymer melt exhibiting liquid crystalline and solid mesophases, and a quantum fluid of interacting bosons.

Progress toward durable and energy-dense lithium-ion batteries has been hindered by instabilities at electrolyte-electrode interfaces, leading to poor cycling stability, and by safety concerns associated with energy-dense lithium metal anodes. Solid polymeric electrolytes (SPEs) can help mitigate these issues; however, the SPE conductivity is limited by sluggish polymer segmental dynamics. We overcome this limitation via zwitterionic SPEs that self-assemble into superionically conductive domains, permitting decoupling of ion motion and polymer segmental rearrangement. Although crystalline domains are conventionally detrimental to ion conduction in SPEs, we demonstrate that semicrystalline polymer electrolytes with labile ion-ion interactions and tailored ion sizes exhibit excellent lithium conductivity (1.6 mS/cm) and selectivity (t + ≈ 0.6-0.8). This new design paradigm for SPEs allows for simultaneous optimization of previously orthogonal properties, including conductivity, Li selectivity, mechanics, and processability.