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Here we provide the 'Global Spectrum of Plant Form and Function Dataset', containing species mean values for six vascular plant traits. Together, these traits -plant height, stem specific density, leaf area, leaf mass per area, leaf nitrogen content per dry mass, and diaspore (seed or spore) mass - define the primary axes of variation in plant form and function. The dataset is based on ca. 1 million trait records received via the TRY database (representing ca. 2,500 original publications) and additional unpublished data. It provides 92,159 species mean values for the six traits, covering 46,047 species. The data are complemented by higher-level taxonomic classification and six categorical traits (woodiness, growth form, succulence, adaptation to terrestrial or aquatic habitats, nutrition type and leaf type). Data quality management is based on a probabilistic approach combined with comprehensive validation against expert knowledge and external information. Intense data acquisition and thorough quality control produced the largest and, to our knowledge, most accurate compilation of empirically observed vascular plant species mean traits to date.

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OBJECTIVE: To evaluate bone mineral content patterns between fracture configurations using novel CT image analysis. ANIMALS: CT images from 97 Thoroughbred racehorses with third metacarpal/tarsal condyle fractures provide the case population for analysis. PROCEDURES: Fractures were grouped by radiographic appearance. Image analysis objectively measured area of highly attenuating pixels (aHAP), areal density of highly attenuating pixels (dHAP) utilizing novel convex hull analysis, and subjective assessment of apparent attenuation intensity ranking (AAIR) for each fracture. Differences between fracture configuration groups were evaluated. RESULTS: Analysis of dHAP identified lower-density regions of highly attenuating pixels in propagating fractures and higher-density regions of highly attenuating pixels in unicortical fractures (P = .028). Complete and incomplete configurations were almost indistinguishable in dHAP (P = 1.000). The ratio of dHAP between fractured and nonfractured condyles revealed higher density gradients between condyles in unicortical (P = .040) and incomplete (P = .031) fractures than propagating fractures. CLINICAL RELEVANCE: Differences in patterns of bone mineral content were identified between propagating, bicortical (incomplete and complete), and unicortical fractures of third metacarpal/tarsal bone condyles. Computer-assisted geometric measurement of dHAP identified on CT images could help to assess fracture risk in equine athletes. This application may have greater relevance as standing CT screening becomes more available.

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Objectives. To examine the effects of within-neighborhood and neighboring characteristics on discrimination, stigma, mental health, and HIV outcomes among Black women living with HIV (BWLWH). Methods. A total of 151 BWLWH in a southeastern US city provided baseline data (October 2019‒January 2020) on experienced microaggressions and discrimination (race-, gender-, sexual orientation-, or HIV-related), mental health (e.g., depression, posttraumatic stress disorder), and HIV outcomes (e.g., viral load, antiretroviral therapy adherence). Neighborhood characteristics by census tract were gathered from the American Community Survey and the National Center for Charitable Statistics. Spatial econometrics guided the identification strategy, and we used the maximum likelihood technique to estimate relationships between a number of predictors and outcomes. Results. Within-neighborhood and neighboring characteristics (employment, education, crime, income, number of religious organizations, and low-income housing) were significantly related to intersectional stigma, discrimination, mental health, HIV viral load, and medication adherence. Conclusions. Policy, research, and interventions for BWLWH need to address the role of neighborhood characteristics to improve quality of life and HIV outcomes. (Am J Public Health. 2022;112(S4):S433-S443. https://doi.org/10.2105/AJPH.2021.306675).

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OBJECTIVE: To evaluate demographic and clinical variables as predictors of nasal high-flow treatment success in newborn infants with respiratory distress cared for in Australian nontertiary special care nurseries. STUDY DESIGN: A secondary analysis of the HUNTER trial, a multicenter, randomized controlled trial evaluating nasal high-flow as primary respiratory support for newborn infants with respiratory distress who were born ≥31 weeks of gestation and with birth weight ≥1200 g, and cared for in Australian nontertiary special care nurseries. Treatment success within 72 hours after randomization to nasal high-flow was determined using objective criteria. Univariable screening and multivariable analysis was used to determine predictors of nasal high-flow treatment success. RESULTS: Infants (n = 363) randomized to nasal high-flow in HUNTER were included in the analysis; the mean gestational age was 36.9 ± 2.7 weeks and birth weight 2928 ± 782 g. Of these infants, 290 (80%) experienced nasal high-flow treatment success. On multivariable analysis, nasal high-flow treatment success was predicted by higher gestational age and lower fraction of inspired oxygen immediately before randomization, but not strongly. The final model was found to have an area under the curve of 0.65, which after adjustment for optimism was found to be 0.63 (95% CI, 0.57-0.70). CONCLUSIONS: Gestational age and supplemental oxygen requirement may be used to guide decisions regarding the most appropriate initial respiratory support for newborn infants in nontertiary special care nurseries. Further prospective research is required to better identify which infants are most likely to be successfully treated with nasal high-flow. TRIAL REGISTRATION: ACTRN12614001203640.

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OBJECTIVE: To determine rates of death or neurodevelopmental impairment (NDI) at 2 years corrected age (primary outcome) in children <32 weeks' gestation randomized to initial resuscitation with a fraction of inspired oxygen (FiO2) value of 0.21 or 1.0. STUDY DESIGN: Blinded assessments were conducted at 2-3 years corrected age with the Bayley Scales of Infant and Toddler Development, Third Edition or the Ages and Stages Questionnaire by intention to treat. RESULTS: Of the 290 children enrolled, 40 could not be contacted and 10 failed to attend appointments. Among the 240 children for whom outcomes at age 2 years were available, 1 child had a lethal congenital anomaly, 1 child had consent for follow-up withdrawn, and 23 children died. The primary outcome, which was available in 238 (82%) of those randomized, occurred in 47 of the 117 (40%) children assigned to initial FiO2 0.21 and in 38 of the 121 (31%) assigned to initial FiO2 1.0 (OR, 1.47; 95% CI, 0.86-2.5; P = .16). No difference in NDI was found in 215 survivors randomized to FiO2 0.21 vs 1.0 (OR, 1.26; 95% CI, 0.70-2.28; P = .11). In post hoc exploratory analyses in the whole cohort, children with a 5-minute blood oxygen saturation (SpO2) <80% were more likely to die or to have NDI (OR, 1.85; 95% CI, 1.07-3.2; P = .03). CONCLUSIONS: Initial resuscitation of infants <32 weeks' gestation with initial FiO2 0.21 had no significant effect on death or NDI compared with initial FiO2 1.0. Further evaluation of optimum initial FiO2, including SpO2 targeting, in a large randomized controlled trial is needed. TRIAL REGISTRATION: Australian and New Zealand Clinical Trials Network Registry ACTRN 12610001059055 and the National Malaysian Research Registry NMRR-07-685-957.

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Earth is home to a remarkable diversity of plant forms and life histories, yet comparatively few essential trait combinations have proved evolutionarily viable in today's terrestrial biosphere. By analysing worldwide variation in six major traits critical to growth, survival and reproduction within the largest sample of vascular plant species ever compiled, we found that occupancy of six-dimensional trait space is strongly concentrated, indicating coordination and trade-offs. Three-quarters of trait variation is captured in a two-dimensional global spectrum of plant form and function. One major dimension within this plane reflects the size of whole plants and their parts; the other represents the leaf economics spectrum, which balances leaf construction costs against growth potential. The global plant trait spectrum provides a backdrop for elucidating constraints on evolution, for functionally qualifying species and ecosystems, and for improving models that predict future vegetation based on continuous variation in plant form and function.

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A trade-off between growth and mortality rates characterizes tree species in closed canopy forests. This trade-off is maintained by inherent differences among species and spatial variation in light availability caused by canopy-opening disturbances. We evaluated conditions under which the trade-off is expressed and relationships with four key functional traits for 103 tree species from Barro Colorado Island, Panama. The trade-off is strongest for saplings for growth rates of the fastest growing individuals and mortality rates of the slowest growing individuals (r2 = 0.69), intermediate for saplings for average growth rates and overall mortality rates (r2 = 0.46), and much weaker for large trees (r2 < or = 0.10). This parallels likely levels of spatial variation in light availability, which is greatest for fast- vs. slow-growing saplings and least for large trees with foliage in the forest canopy. Inherent attributes of species contributing to the trade-off include abilities to disperse, acquire resources, grow rapidly, and tolerate shade and other stresses. There is growing interest in the possibility that functional traits might provide insight into such ecological differences and a growing consensus that seed mass (SM), leaf mass per area (LMA), wood density (WD), and maximum height (H(max)) are key traits among forest trees. Seed mass, LMA, WD, and H(max) are predicted to be small for light-demanding species with rapid growth and mortality and large for shade-tolerant species with slow growth and mortality. Six of these trait-demographic rate predictions were realized for saplings; however, with the exception of WD, the relationships were weak (r2 < 0.1 for three and r2 < 0.2 for five of the six remaining relationships). The four traits together explained 43-44% of interspecific variation in species positions on the growth-mortality trade-off; however, WD alone accounted for > 80% of the explained variation and, after WD was included, LMA and H(max) made insignificant contributions. Virtually the full range of values of SM, LMA, and H(max) occurred at all positions on the growth-mortality trade-off. Although WD provides a promising start, a successful trait-based ecology of tropical forest trees will require consideration of additional traits.

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• Here we explore the possible role of leaf-level gas exchange traits in determining growth rate differences and competitive interactions between evergreen angiosperms and conifers. • We compared relationships among photosynthetic capacity (Amax ), maximum stomatal conductance (Gs ), leaf life span, nitrogen concentration (N) and specific leaf area (SLA), in sun leaves of 23 evergreen angiosperm and 20 conifer populations. • Despite similar average leaf Nmass , conifer leaves lived longer on average (36 months) than angiosperms (25 months). At a standardized leaf N, Amass was higher in angiosperms (56 nmol g-1 s-1 ) than in conifers (36 nmol g-1 s-1 ). Stepwize regression suggested that most of this difference in photosynthetic nitrogen use efficiency could be explained by Gs and SLA. Mean Gs (on an area basis) of angiosperms was higher than that of conifers (152 vs 117 mmol m2 s-1 ), but Aarea -Gs relationships were similar for the two groups. At a given leaf N, conifers had lower SLA (projected area basis) than angiosperms. • Photosynthetic differences probably contribute to the competitive advantage of angiosperm trees over conifers in productive habitats, and may be linked to the greater hydraulic capacity of vessels, enabling angiosperms to develop higher stomatal conductance and therefore sustain higher transpiration rates.