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Traction force microscopy (TFM) is a widely used technique to measure cell contractility on compliant substrates that mimic the stiffness of human tissues. For every step in a TFM workflow, users make choices which impact the quantitative results, yet many times the rationales and consequences for making these decisions are unclear. We have found few papers which show the complete experimental and mathematical steps of TFM, thus obfuscating the full effects of these decisions on the final output.

Therefore, we present this “Field Guide” with the goal to explain the mathematical basis of common TFM methods to practitioners in an accessible way. We specifically focus on how errors propagate in TFM workflows given specific experimental design and analytical choices.

We cover important assumptions and considerations in TFM substrate manufacturing, substrate mechanical properties, imaging techniques, image processing methods, approaches and parameters used in calculating traction stress, and data-reporting strategies.

By presenting a conceptual review and analysis of TFM-focused research articles published over the last two decades, we provide researchers in the field with a better understanding of their options to make more informed choices when creating TFM workflows depending on the type of cell being studied. With this review, we aim to empower experimentalists to quantify cell contractility with confidence.

Woody plant encroachment poses a significant threat to grasslands globally, and in the southcentral USA, juniper (Juniperus virginiana) is rapidly taking over large areas of grasslands. Despite ongoing research, the reasons behind the rapid encroachment of juniper species in Oklahoma remain elusive. We hypothesized that the interaction between juniper canopy, aeolian, and wet-deposition processes lead to a modification in trace-element inputs through stemflow and throughfall. This, in turn, plays a crucial role in determining the success of juniper encroachment.

We measured the influx of trace-elements in stemflow and throughfall beneath juniper canopies of different sizes, contrasting the results with those obtained under ambient precipitation.

Our research unveiled a significant influence of the juniper canopy on trace-element inputs via stemflow and throughfall. Specifically, there was a significant increase in manganese, boron, and chlorine inputs, coupled with a decrease in copper inputs. Additionally, there was an increase in most cations and sulfate.

Our results indicate that juniper encroachment alters the profile of trace-element, cation, and anion inputs beneath their canopies. Increased levels of manganese and reduction of copper inputs into the ecosystem may enhance the juniper growth, creating a positive feedback mechanism that could contribute to the success of juniper and other woody encroachers.

The study explored the mediating role of Chinese American parents' ethnic–racial identity (ERI) in linking their discrimination experiences, ethnic–racial socialization (ERS), and their children's mental health, testing whether neighborhood racial diversity and perceived Chinese density moderated these mediation paths.

During COVID‐19, Chinese American families faced increased discrimination, impacting their mental well‐being. However, few studies have examined how parents' discrimination experiences influence their ERI, ERS practice, and ultimately their children's mental health difficulties.

Data from 294 Chinese immigrant parents (M_age = 44.28, 79% female) were collected in two waves, 2020 and 2021. Path analysis tested if parental discrimination affects their ERI and ERS, and children's mental health. Multigroup analysis assessed if mediation models varied for families living in communities with low versus high racial diversity or Chinese density.

Parental racism‐related stress at T1 had significant indirect effects on parental ERS practices (higher use of maintenance of heritage culture and lower use of avoidance of outgroups practice) at T2 via parental ERI (greater private regard) at T2. Parental racial discrimination (perceived sinophobia in the media and racism‐related stress) at T1 had significant indirect effects on children's mental health difficulties at T2 via parental ERS practices (use of maintenance of heritage culture and avoidance of outgroups practices) at T2. The neighborhood racial diversity moderated the mediation model.

These findings advance the understanding of both individual (i.e., parental ERI) and contextual factors (i.e., neighborhood racial diversity) in the complex associations between parents' discrimination experiences and children's mental health difficulties.

Most of the world's food crops are dependent on pollinators. However, there is a great deal of uncertainty in the strength of this relationship, especially regarding the relative contributions of the honey bee (often a managed species) and wild insects to crop yields on a global scale. Previous data syntheses have likewise reached differing conclusions on whether pollinator species diversity, or only the number of pollinator visits to flowers, is important to crop yield. This study quantifies the current state of these relationships and links to a dynamic version of our analyses that updates automatically as studies become available.

Global.

Present.

Insect pollinators of global crops.

Using a newly created database of 93 crop pollination studies across six continents that roughly triples the number of studies previously available, we analysed the relationship between insect visit rates, pollinator diversity, and crop yields in a series of mixed‐effects models.

We found that honey bees and wild insects contribute roughly equal amounts to crop yields worldwide, having similar average flower visitation rates and producing similar increases in yield per visit. We also found that pollinator species diversity was positively associated with increased crop yields even when total visits from all species are accounted for, though it was less explanatory than the total number of visits itself.

Our analysis suggests a middle ground where honey bees are not responsible for the vast majority of crop pollination as has often been assumed in the agricultural literature, and likewise wild insects are not vastly more important than honey bees, as recent global analyses have reported. We also conclude that while pollinator diversity is less important than the number of pollinator visits, these typically involve many species, underscoring the importance of conserving a diversity of wild pollinators.

The community cultural wealth (CCW) theoretical framework recognizes the assets of oppressed communities. Within the framework, aspirational capital refers to the hope to achieve in the face of systemic barriers, while navigational capital includes tactics engaged to progress within institutions that were not designed for equitable achievement. This study explores where aspirational capital and navigational capital overlap (a frequent and theoretically relevant occurrence) for marginalized‐identity (MI) STEM (science, technology, engineering, and mathematics) students.

This study provides insight into the experiences of higher education for MI students. Understanding students' deployment of navigational and aspirational capitals can direct change within institutions.

This analysis draws on 51 semi‐structured interviews with 26 participants. Multiple rounds of qualitative coding and shared meaning‐making among authors support the present findings.

When aspirational capital and navigational capital overlap in student experience, three themes emerge. First, MI students use individualized actions to meet their goals; their extreme self‐reliance and engagement of priorities and milestones are key. Second, intrinsic motivators echoing meritocratic narratives encourage students. These narratives emphasize the value of hard work and taking advantage of opportunities. Finally, external forces, including institutionally based experts and culture, reflect aspirational and navigational capital engagement that support the individual's approaches and mindsets. Each finding includes nuance based on demographic categories.

MI students draw on aspirational and navigational capital for support in postsecondary education. Recognition of CCW components and strategies shifts the responsibility of equitable student experiences and academic success to institutions and stakeholders in STEM higher education.

Trailing-edge populations at the low-latitude, receding edge of a shifting range face high extinction risk from climate change unless they are able to track optimal environmental conditions through dispersal.

We fit dispersal models to the locations of 3165 individually-marked black-throated blue warblers (Setophaga caerulescens) in the southern Appalachian Mountains in North Carolina, USA from 2002 to 2023. Black-throated blue warbler breeding abundance in this population has remained relatively stable at colder and wetter areas at higher elevations but has declined at warmer and drier areas at lower elevations.

Median dispersal distance of young warblers was 917 m (range 23–3200 m), and dispersal tended to be directed away from warm and dry locations. In contrast, adults exhibited strong site fidelity between breeding seasons and rarely dispersed more than 100 m (range 10–1300 m). Consequently, adult dispersal kernels were much more compact and symmetric than natal dispersal kernels, suggesting adult dispersal is unlikely a driving force of declines in this population.

Our findings suggest that directional natal dispersal may mitigate fitness costs for trailing-edge populations by allowing individuals to track changing climate and avoid warming conditions at warm-edge range boundaries.

Rice is prone to Cd uptake under aerobic soil conditions primarily due to the OsNramp5 Mn transport pathway. Unlike Cd, Mn availability in rice paddies decreases as redox potential increases. We tested whether increasing Mn concentrations in solution would decrease Cd accumulation in rice through competition between Mn and Cd for uptake and/or suppression ofOsNramp5expression.

Rice was grown to maturity under Mn concentrations that spanned three orders of magnitude (0.30 to 37 μM) that corresponded to free Mn²⁺activities of 10^–7.9to 10^–5.0 M while free Cd²⁺activity was held as constant as achievable (10^–10.2to 10^–10.4 M). Plant biomass and elemental concentrations were measured in roots and shoots at each stage. Fold changes in the expression ofOsNramp5,OsCd1,OsHMA3,OsCCX2, andOsYSL6genes in vegetative and grain-filling stages of rice plants were determined.

Competition between Mn and Cd for root uptake and accumulation in shoots was observed at the highest concentration of Mn tested.OsNramp5expression was significantly higher in rice plants at the vegetative stage compared to the grain-filling stage, whileOsCd1andOsHMA3showed the opposite. Solution Mn concentrations previously thought to be tolerable by rice grown to the vegetative stage led to Mn toxicity as plants matured.

Mn competes with Cd during uptake into rice withOsNramp5expression unaffected. Different translocation paths may occur for Mn and Cd within the rice plant and over the rice life cycle, withOsCCX2correlated with shoot Cd concentration.

In scientific inquiry learning, students often have difficulties conducting hypothetical reasoning with multiple intertwined variables. Concept maps have a potential to facilitate complex thinking and reasoning. However, there is little investigation into the content of student‐constructed concept maps and its association with inquiry task performance.

This study explored students' concept mapping style and its association with task performance in computer‐based inquiry learning.

An exploratory study was conducted with 80 Grade 11 students, who collaboratively constructed concept maps in a free style to support inquiry learning with a virtual ecosystem. Student‐constructed concept maps was analysed by firstly identifying different types of propositions formed in the maps and then determining the style of each concept map based on the dominant type of propositions in the map. Finally, the association between the concept map style and inquiry task performance was explored.

Two major concept map styles were identified: (1) knowledge‐oriented concept maps (KCMs) mainly representing problem‐related subject knowledge as a set of concepts and their relationships, and (2) problem‐oriented concept maps (PCMs) mainly representing problem situation as a sequence of changes and their causal relationships. Compared with those constructing KCMs, the students constructing PCMs formed higher‐quality propositions in their maps and performed better in hypothesising, reasoning, and drawing conclusions in the inquiry task.

Besides KCMs, students in inquiry learning can be encouraged to construct PCMs to foster effective thinking and reasoning; that is, constructing a concept map to represent the problem situation as a sequence of changes and the causal relationships between the changes.

Congenital cytomegalovirus (cCMV) is the most common congenital viral infection in the United States. Symptomatic infections can cause severe hearing loss and neurological disability, although ~ 90% of cCMV infections are asymptomatic at birth. Despite its prevalence, the long-term neurobehavioral risks of asymptomatic cCMV infections are not fully understood. The objective of this work was to evaluate for potential long-term neurobehavioral sequelae in infants with asymptomatic cCMV.

Infants with cCMV were identified from a universal newborn cCMV screening study in a metropolitan area in the midwestern United States. Asymptomatic infants with cCMV were enrolled in a longitudinal neurodevelopmental study (N = 29). Age- and sex-matched healthy control infants (N = 193) were identified from the Baby Connectome Project (BCP), a longitudinal study of brain and behavioral development. The BCP sample supplemented an additional group of healthy control infants (N = 30), recruited from the same participant registry as the BCP specifically for comparison with infants with asymptomatic cCMV. Neurobehavioral assessments and parent questionnaires, including the Mullen Scales of Early Learning, the Repetitive Behavior Scales for Early Childhood (RBS-EC), and the Infant Toddler Social Emotional Assessment (ITSEA) were administered at 12 months of age. Neurobehavioral scores were compared between infants with asymptomatic cCMV and all identified healthy control infants.

Infants with asymptomatic cCMV performed equivalently compared to healthy control infants on the neurobehavioral measures tested at 12 months of age.

These results indicate that at 12 months of age, infants with asymptomatic cCMV are not statistically different from controls in a number of neurobehavioral domains. Although follow-up is ongoing, these observations provide reassurance about neurobehavioral outcomes for infants with asymptomatic cCMV and inform the ongoing discussion around universal screening. Additional follow-up will be necessary to understand the longer-term outcomes of these children.

Quantifying the phylogenetic diversity of temperate trees is essential for understanding the processes that have shaped the modern distribution of temperate broadleaf forest and other major forest biomes. Here, we focus on Fagales, an iconic member of forests worldwide, to uncover global diversity and endemism patterns and investigate the distribution of root nodule symbiosis (RNS), an important morphological specialisation in this clade, as a key factor behind these patterns.

Global.

Fagales.

We combined phylogenetic data covering 60.2% of living species, fine‐scale distribution models covering 90% of species, and nodulation data covering all species to investigate the distribution of species richness and phylogenetic diversity at fine spatial scales compared to the distribution of RNS. We identify abiotic environmental factors associated with RNS and with Fagales diversity in general.

We find the highest species richness in temperate east Asia, eastern North America, and equatorial montane regions of Asia and Central America. By contrast, relative phylogenetic diversity (RPD) is highest at higher latitudes, where RNS also predominates. We found a strong spatial structuring of regionalisations of Fagales floras, reflecting distinct Northern and Southern Hemisphere floras (except a unique Afro‐Boreal region), each with distinct RNS‐environment relationships.

Although species richness and phylogenetic regionalisation for Fagales accord well with traditional biogeographic concepts for temperate forests, this is not the case for RPD. RNS is almost universal in the highest RPD regions, which may reflect ecological filtering promoting RNS in these regions. Our results highlight the utility of global‐scale, clade‐specific spatial phylogenetics and its utility for understanding drivers of diversity in species‐rich clades.