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Purpose: We questioned how root ideotypes selected for deep or shallow root architecture function in complex environments with heterogeneous distributions of phosphorus (P), such as in many cropping systems in north-eastern Australia. Methods: We used the rhizobox method to evaluate how contrasting genotypes of durum wheat and sorghum (wide and narrow root angle) responded to combinations of starter-P and deep P bands. Results: Although we found evidence that root angle may influence spatio-temporal exploration for deep P bands, (early) plant access to P was the critical driver for plant growth. Without P, root system growth was retarded such that genotypic differences were hardly observed. Access to P boosted root exploration at depth by virtue of greater root system size, such that wide-angle genotypes with P outperformed narrow-angle ones without P. Plastic root responses to P benefited the expression of the broader root system architecture. We observed variation between species and individual parameters, but overall Starter-P and deep P bands tended to deliver complementary benefits when considering plant growth, P uptake, and phenological development together. Conclusion: Our study highlights that nutritional constraints may limit the ability of root ideotypes to function in complex target environments. Development and deployment of root ideotypes should consider how local conditions (including soil nutrient distribution, physical and biological properties) influence crop phenotype and their ability to deliver the intended benefits. Within this, soil nutrient management is a critical determinant and an opportunity to influence the target environment. [ABSTRACT FROM AUTHOR]

The article discusses soil carbon losses in runoff and erosion from sugarcane farming systems in subtropical northeast Australia. Topics discussed include carbon losses in runoff from sugarcane farming systems in Southeast Queensland and the modules for growers contained in the Smartcane BMP program. The effect of land management practices on runoff carbon losses in sugarcane cropping systems is also discussed.

• Soil properties influence long-term P transformations in fertospheres. • P pools were examined in-situ using soil solution, isotopic dilution, and XANES. • P precipitation and sorption reactions were ongoing at 12 months. • Potentially-plant available P was controlled by soil type. Identifying the effects of soil properties on the transformations of phosphorus (P) in highly concentrated fertiliser bands is a critical component in improving P fertiliser use efficiency, but little is known regarding the kinetics of P transformation, including over longer periods of time that are relevant to multiple cropping seasons. In the present study, we utilised a 12-month soil-fertiliser incubation experiment to simulate deep-placed banded P fertilisers, investigating three contrasting soils from Australia, three P sources, and the co-application of potassium (K). Overall, concentrations of soil solution P in the fertosphere decreased substantially over time regardless of soil type and P form. In the Ultisol and Vertisol, this progressive decrease was due to the precipitation of aluminium-phosphates (and, to a lesser extent, magnesium-phosphates) as well as ongoing sorption reactions, whilst in the alkaline Alfisol this progressive decrease was due to precipitation of calcium-phosphates. Despite P precipitation and sorption reactions, concentrations of potentially-plant available P measured by isotopically exchangeable P within 24 h (Ee24h) remained relatively constant between 1 and 12 months for the Ultisol and Vertisol, with this indicating that the ongoing sorption reactions of P in these fertospheres of non-calcareous soils may not necessarily decrease plant availability over time. We also found that co-application of K resulted in further reduction in P availability in all three soils and was mediated by K displacement of other exchangeable cations, thereby increasing precipitation reactions with dominant minerals. To improve P use efficiency in semi-arid cropping environments, optimising P form as a function of soil type is critical, especially for systems that are reliant on subsoil moisture and where highly concentrated fertiliser bands are applied infrequently to supply P over multiple growing seasons. [ABSTRACT FROM AUTHOR]

Importance: Traumatic brain injury (TBI) is a leading cause of death and disability in children, and predicting functional outcome after TBI is challenging. Magnetic resonance imaging (MRI) is frequently conducted after severe TBI; however, the predictive value of MRI remains uncertain., Objectives: To identify early MRI measures that predict long-term outcome after severe TBI in children and to assess the added predictive value of MRI measures over well-validated clinical predictors., Design, Setting, and Participants: This preplanned prognostic study used data from the Approaches and Decisions in Acute Pediatric TBI (ADAPT) prospective observational comparative effectiveness study. The ADAPT study enrolled 1000 consecutive children (aged <18 years) with severe TBI between February 1, 2014, and September 30, 2017. Participants had a Glasgow Coma Scale (GCS) score of 8 or less and received intracranial pressure monitoring. Magnetic resonance imaging scans performed as part of standard clinical care within 30 days of injury were collected at 24 participating sites in the US, UK, and Australia. Summary imaging measures were correlated with the Glasgow Outcome Scale-Extended for Pediatrics (GOSE-Peds), and the predictive value of MRI measures was compared with the International Mission for Prognosis and Analysis of Clinical Trials in TBI (IMPACT) core clinical predictors. Data collection, image analysis, and data analyses were completed in July 2023., Exposures: Pediatric severe TBI with an MRI scan performed as part of clinical care., Main Outcomes and Measures: All measures were selected a priori. Magnetic resonance imaging measures included contusion, ischemia, diffuse axonal injury, intracerebral hemorrhage, and brainstem injury. Clinical predictors included the IMPACT core measures (GCS motor score and pupil reactivity). All models adjusted for age and sex. Outcome measures included the GOSE-Peds score obtained at 3, 6, and 12 months after injury., Results: This study included 233 children with severe TBI who were enrolled at participating sites and had an MRI scan and preselected clinical predictors available. Their median age was 6.9 (IQR, 3.0-13.3) years, and more than half of participants (134 [57.5%]) were male. In a multivariable model including MRI measures and IMPACT core clinical variables, contusion volume (odds ratio [OR], 1.13; 95% CI, 1.02-1.26), brain ischemia (OR, 2.11; 95% CI, 1.58-2.81), brainstem lesions (OR, 5.40; 95% CI, 1.90-15.35), and pupil reactivity were each independently associated with GOSE-Peds score. Adding MRI measures to the IMPACT clinical predictors significantly improved model fit and discrimination between favorable and unfavorable outcomes compared with IMPACT predictors alone (area under the receiver operating characteristic curve, 0.77; 95% CI, 0.72-0.85 vs 0.67; 95% CI, 0.61-0.76 for GOSE-Peds score >3 at 6 months after injury)., Conclusions and Relevance: In this prognostic study of children with severe TBI, the addition of MRI measures significantly improved outcome prediction over well-established and validated clinical predictors. Magnetic resonance imaging should be considered in children with severe TBI to inform prognosis and may also promote stratification of patients in future clinical trials.

Objectives: To understand the relationship between the timing of initiation of nutritional support in children with severe traumatic brain injury and outcomes., Design: Secondary analysis of a randomized, controlled trial of therapeutic hypothermia (Pediatric Traumatic Brain Injury Consortium: Hypothermia, also known as "the Cool Kids Trial" (NCT 00222742)., Settings: Fifteen clinical sites in the United States, Australia, and New Zealand., Subjects: Inclusion criteria included 1) age less than 18 years, 2) postresuscitation Glasgow Coma Scale less than or equal to 8, 3) Glasgow Coma Scale motor score less than 6, and 4) available to be randomized within 6 hours after injury. Exclusion criteria included normal head CT, Glasgow Coma Scale equals to 3, hypotension for greater than 10 minutes (< fifth percentile for age), uncorrectable coagulopathy, hypoxia (arterial oxygen saturation < 90% for > 30 min), pregnancy, penetrating injury, and unavailability of a parent or guardian to consent at centers without emergency waiver of consent., Interventions: Therapeutic hypothermia (32-33°C for 48 hr) followed by slow rewarming for the primary study. For this analysis, the only intervention was the extraction of data regarding nutritional support from the existing database., Measurements and Main Results: Timing of initiation of nutritional support was determined and patients stratified into four groups (group 1-no nutritional support over first 7 d; group 2-nutritional support initiated < 48 hr after injury; group 3-nutritional support initiated 48 to < 72 hr after injury; group 4-nutritional support initiated 72-168 hr after injury). Outcomes were also stratified (mortality and Glasgow Outcomes Scale-Extended for Pediatrics; 1-4, 5-7, 8) at 6 and 12 months. Mixed-effects models were performed to define the relationship between nutrition and outcome. Children (n = 90, 77 randomized, 13 run-in) were enrolled (mean Glasgow Coma Scale = 5.8); the mortality rate was 13.3%. 57.8% of subjects received hypothermia Initiation of nutrition before 72 hours was associated with survival (p = 0.01), favorable 6 months Glasgow Outcomes Scale-Extended for Pediatrics (p = 0.03), and favorable 12 months Glasgow Outcomes Scale-Extended for Pediatrics (p = 0.04). Specifically, groups 2 and 3 had favorable outcomes versus group 1., Conclusions: Initiation of nutritional support before 72 hours after traumatic brain injury was associated with decreased mortality and favorable outcome in this secondary analysis. Although this provides a rationale to initiate nutritional support early after traumatic brain injury, definitive studies that control for important covariates (severity of injury, clinical site, calories delivered, parenteral/enteral routes, and other factors) are needed to provide definitive evidence on the optimization of the timing of nutritional support after severe traumatic brain injury in children.

Objective: To evaluate the association between neuromuscular blocking agents and outcome, intracranial pressure, and medical complications in children with severe traumatic brain injury., Design: A secondary analysis of a randomized, controlled trial of therapeutic hypothermia., Setting: Seventeen hospitals in the United States, Australia, and New Zealand., Patients: Children (< 18 yr) with severe traumatic brain injury., Interventions: None for this secondary analysis., Measurements and Main Results: Children received neuromuscular blocking agent on the majority of days of the study (69.6%), and the modified Pediatric Intensity Level of Therapy scores (modified by removing neuromuscular blocking agent administration from the score) were increased on days when neuromuscular blocking agents were used (9.67 ± 0.21 vs 5.48 ± 0.26; p < 0.001). Children were stratified into groups based on exposure to neuromuscular blocking agents (group 1 received neuromuscular blocking agents each study day; group 2 did not). Group 1 had increased number of daily intracranial pressure readings more than 20 mm Hg (4.4 ± 1.1 vs 2.4 ± 0.5;p = 0.015) and longer ICU and hospital length of stay (p = 0.003 and 0.07, respectively, Kaplan-Meier). The Glasgow Outcome Score-Extended for Pediatrics at hospital discharge and 3, 6, and 12 months after traumatic brain injury and medical complications observed during the acute hospitalization were similar between groups., Conclusions: Administration of neuromuscular blocking agents was ubiquitous and daily administration of neuromuscular blocking agents was associated with intracranial hypertension but not outcomes-likely indicating that increased injury severity prompted their use. Despite this, neuromuscular blocking agent use was not associated with complications. A different study design-perhaps using randomization or methodologies-of a larger cohort will be required to determine if neuromuscular blocking agent use is helpful after severe traumatic brain injury in children.