Investigating the "scapula sign" as an indicator of rickets.

OBJECTIVE: In 1971, Weiss identified a "scapula sign" comprising a defect at the inferior angle of the scapula in juveniles with vitamin D deficiency rickets, but this has been little studied since. This study aimed to explore pathological variation of this defect in juveniles with other skeletal manifestations of vitamin D deficiency rickets. MATERIALS AND METHODS: 527 juveniles, aged from birth to 12 years, from two post-medieval British assemblages were macroscopically evaluated to document the range of pathological changes at the inferior angle. Scapula maximum lengths were recorded and supplementary radiographs were assessed. RESULTS: Blunting, flattening or squaring of the inferior angle occurred in 34 of 155 (22%) juveniles with other indicators of rickets and occurred frequently in cases of severe active rickets. Coarsening of the border and cupping deformities were identified radiographically, as well as residual defects in healed cases. Scapula lengths in juveniles with active rickets did not consistently deviate from those expected in any age group. CONCLUSIONS: The scapula sign is identifiable in some children with rickets. Differential diagnoses of scapula defects are important but the socio-cultural and environmental context of this sample suggests a link to vitamin D deficiency. SIGNIFICANCE: This finding expands the range of pathological changes known to occur in rickets, helping to improve recognition of this condition in past groups. LIMITATIONS: Small sample sizes prevented observation of the defect in adolescents with rickets. Defects can affect the positioning of standardised scapula length measures, complicating assessments of growth impacts. SUGGESTIONS FOR FUTURE RESEARCH: Continued research into the range of skeletal changes that can develop in vitamin D deficiency to improve the identification of this deficiency in past groups.

An immune dysfunction score for stratification of patients with acute infection based on whole-blood gene expression.

Dysregulated host responses to infection can lead to organ dysfunction and sepsis, causing millions of global deaths each year. To alleviate this burden, improved prognostication and biomarkers of response are urgently needed. We investigated the use of whole-blood transcriptomics for stratification of patients with severe infection by integrating data from 3149 samples from patients with sepsis due to community-acquired pneumonia or fecal peritonitis admitted to intensive care and healthy individuals into a gene expression reference map. We used this map to derive a quantitative sepsis response signature (SRSq) score reflective of immune dysfunction and predictive of clinical outcomes, which can be estimated using a 7- or 12-gene signature. Last, we built a machine learning framework, SepstratifieR, to deploy SRSq in adult and pediatric bacterial and viral sepsis, H1N1 influenza, and COVID-19, demonstrating clinically relevant stratification across diseases and revealing some of the physiological alterations linking immune dysregulation to mortality. Our method enables early identification of individuals with dysfunctional immune profiles, bringing us closer to precision medicine in infection.

Different factors limit early- and late-season windows of opportunity for monarch development.

Seasonal windows of opportunity are intervals within a year that provide improved prospects for growth, survival, or reproduction. However, few studies have sufficient temporal resolution to examine how multiple factors combine to constrain the seasonal timing and extent of developmental opportunities. Here, we document seasonal changes in milkweed (Asclepias fascicularis)-monarch (Danaus plexippus) interactions with high resolution throughout the last three breeding seasons prior to a precipitous single-year decline in the western monarch population. Our results show early- and late-season windows of opportunity for monarch recruitment that were constrained by different combinations of factors. Early-season windows of opportunity were characterized by high egg densities and low survival on a select subset of host plants, consistent with the hypothesis that early-spring migrant female monarchs select earlier-emerging plants to balance a seasonal trade-off between increasing host plant quantity and decreasing host plant quality. Late-season windows of opportunity were coincident with the initiation of host plant senescence, and caterpillar success was negatively correlated with heatwave exposure, consistent with the hypothesis that late-season windows were constrained by plant defense traits and thermal stress. Throughout this study, climatic and microclimatic variations played a foundational role in the timing and success of monarch developmental windows by affecting bottom-up, top-down, and abiotic limitations. More exposed microclimates were associated with higher developmental success during cooler conditions, and more shaded microclimates were associated with higher developmental success during warmer conditions, suggesting that habitat heterogeneity could buffer the effects of climatic variation. Together, these findings show an important dimension of seasonal change in milkweed-monarch interactions and illustrate how different biotic and abiotic factors can limit the developmental success of monarchs across the breeding season. These results also suggest the potential for seasonal sequences of favorable or unfavorable conditions across the breeding range to strongly affect monarch population dynamics.

Ontogenetic changes in femoral cross-sectional geometry during childhood locomotor development.

OBJECTIVES: The femur is a major weight-bearing bone that is variably loaded throughout growth as children transition through locomotory states prior to the attainment of a mature bipedal gait. Here, we document ontogenetic trends in femoral cross-sectional geometry (CSG) and explore how changes in loading regime may impact the structural arrangement of cortical bone along the length of the developing diaphysis. MATERIALS AND METHODS: Micro-CT scans of 110 immature femora were generated from a documented archaeological sample ranging in age from birth to 8.5 years old. CSG properties indicative of relative bone strength and bending rigidity were analyzed from cross-sections extracted at 35%, 50% and 65% of total intermetaphyseal length. RESULTS: Infants experience a marked redistribution of cortical bone between birth and 7 months facilitating a more advantageous mechanical structure for early load bearing behaviors as bone is displaced further from the section centroid. Early walkers are characterized by a mediolaterally reinforced cross-section that becomes more circular as gait continues to develop. DISCUSSION: During ontogeny the femur undergoes distinct morphological phases, which correspond with changes in loading regime. This study illustrates the importance of loading conditions in shaping immature bone morphology. Nonmechanical factors such as changes in hormonal environmental can also impact on this dynamic.

Using standards to improve middle school students' accuracy at evaluating the quality of their recall.

When recalling key term definitions from class materials, students may recall entirely incorrect definitions, yet will often claim that these commission errors are entirely correct; that is, they are overconfident in the quality of their recall responses. We investigated whether this overconfidence could be reduced by providing various standards to middle school students as they evaluated their recall responses. Students studied key term definitions, attempted to recall each one, and then were asked to score the quality of their recall. In Experiment 1, they evaluated their recall responses by rating each response as fully correct, partially correct, or incorrect. Most important, as they evaluated a particular response, it was presented either alone (i.e., without a standard) or with the correct definition present. Providing this full-definition standard reduced overconfidence in commission errors: Students assigned full or partial credit to 73% of their commission errors when they received no standard, whereas they assigned credit to only 44% of these errors when receiving the full-definition standard. In Experiment 2, a new standard was introduced: Idea units from each definition were presented, and students indicated whether each idea unit was in their response. After making these idea-unit judgments, the students then evaluated the quality of their entire response. Idea-unit standards further reduced overconfidence. Thus, although middle school students are overconfident in evaluating the quality of their recall responses, using standards substantially reduces this overconfidence and promises to improve the efficacy of their self-regulated learning.