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Anthropogenic CO 2 emissions are acidifying the world’s oceans. A growing body of evidence demonstrates that ocean acidification can impact survival, growth, development and physiology of marine invertebrates. Here, we tested the impact of long-term (up to 16 months) and trans-life-cycle (adult, embryo/larvae and juvenile) exposure to elevated p CO 2 (1,200 μatm, compared to control 400 μatm) on the green sea urchin Strongylocentrotus droebachiensis . Female fecundity was decreased 4.5-fold when acclimated to elevated p CO 2 for 4 months during reproductive conditioning, while no difference was observed in females acclimated for 16 months. Moreover, adult pre-exposure for 4 months to elevated p CO 2 had a direct negative impact on subsequent larval settlement success. Five to nine times fewer offspring reached the juvenile stage in cultures using gametes collected from adults previously acclimated to high p CO 2 for 4 months. However, no difference in larval survival was observed when adults were pre-exposed for 16 months to elevated p CO 2 . p CO 2 had no direct negative impact on juvenile survival except when both larvae and juveniles were raised in elevated p CO 2 . These negative effects on settlement success and juvenile survival can be attributed to carry-over effects from adults to larvae and from larvae to juveniles. Our results support the contention that adult sea urchins can acclimate to moderately elevated p CO 2 in a matter of a few months and that carry-over effects can exacerbate the negative impact of ocean acidification on larvae and juveniles.

BACKGROUND AND AIMS: Root functional traits are determinants of soil carbon storage; plant productivity; and ecosystem properties. However, few studies look at both annual and perennial roots, soil properties, and productivity in the context of field scale agricultural systems. METHODS: In Long Term and Conversion studies in North Central Kansas, USA; root biomass and length, soil carbon and nitrogen, microbial biomass, nematode and micro-arthropod communities were measured to a depth of one meter in paired perennial grassland and cropland wheat sites as well as a grassland site that had been converted to cropland using no tillage five years prior. RESULTS: In the Long Term Study root biomass was three to seven times greater (9.4 Mg ha⁻¹ and 2.5 Mg ha⁻¹ in May), and root length two times greater (52.5 km m⁻2 and 24.0 km m⁻² in May) in perennial grassland than in cropland. Soil organic carbon and microbial biomass carbon were larger, numbers of Orbatid mites greater (2084 vs 730 mites m⁻²), and nematode communities more structured (Structure Index 67 vs 59) in perennial grassland versus annual cropland. Improved soil physical and biological properties in perennial grasslands were significantly correlated with larger, deeper root systems. In the Conversion Study root length and biomass, microbial biomass carbon, mite abundance and nematode community structure differed at some but not all dates and depths. Isotope analysis showed that five years after no-till conversion old perennial roots remained in soils of annual wheat fields and that all soil fractions except coarse particulate organic matter were derived from C₄ plants. CONCLUSIONS: Significant correlation between larger, longer roots in grasslands compared to annual croplands and improved soil biological, physical and chemical properties suggest that perennial roots are an important factor allowing perennial grasslands to maintain productivity and soil quality with few inputs. Perennial roots may persist and continue to influence soil properties long after conversion to annual systems.

Large coherent structures over vegetation canopies are responsible for a substantial part of the turbulent transfer of momentum, heat and mass between the canopy and the atmosphere. As forested landscapes are often fragmented, edge regions may be of importance in turbulent transfer. The development of coherent structures from the leading edge of a forest is investigated here for the first time. For this purpose, the turbulent flow over a clearing–forest pattern is simulated using the Advanced Regional Prediction System (ARPS). In previous studies the code has been modified so as to simulate turbulent flows at very fine scale (0.1h, where h is the mean canopy height) within and above heterogeneous vegetation canopies, using a large-eddy simulation (LES) approach. Validations have also been performed over homogeneous forest canopies and over a simple forest–clearing–forest pattern, against field and wind-tunnel measurements. Here, a schematic picture of the development of coherent eddies downstream from the leading edge of a forest is extracted from the mean vorticity components, the Q-criterion field, the cross-correlation of the wind velocity components and the length and separation length scales of coherent structures, determined by using a wavelet transform. This schematic picture shows strong similarities with the development of coherent structures observed in a mixing layer, with four different regions: (i) close to the edge, Kelvin–Helmholtz instabilities develop when a strong wind gust hits the canopy; (ii) these instabilities roll over to form transverse vortices from around 3h downstream from the edge, characterized by a length scale close to the depth of the internal boundary layer that develops from the canopy edge; (iii) secondary instabilities destabilize these rollers and increase the vertical and streamwise vorticity components from around 6h, and two counter-rotating streamwise vortices appear; (iv) at about 9h the initial rollers have become complex three-dimensional coherent structures, with spatially constant mean length and separation length scales. These four stages of development occur closer to the edge with increasing canopy density. While this average picture of the development of coherent structures is similar to that observed in a mixing layer, the analysis of instantaneous fields shows that coherent structures behind the leading edge appear as resulting from the ‘branching’ of tubes localized in regions of low pressure, where their cores are characterized by high values of enstrophy and Q-criterion.

As a consequence of increasing atmospheric CO₂, the world's oceans are warming and slowly becoming more acidic (ocean acidification, OA) and profound changes in marine ecosystems are certain. Calcification is one of the primary targets for studies of the impact of CO₂-driven climate change in the oceans and one of the key marine groups most likely to be impacted by predicted climate change events are the echinoderms. Echinoderms are a vital component of the marine environment with representatives in virtually every ecosystem, where they are often keystone ecosystem engineers. This paper reviews and analyses what is known about the impact of near-future ocean acidification on echinoderms. A global analysis of the literature reveals that echinoderms are surprisingly robust to OA and that important differences in sensitivity to OA are observed between populations and species. However, this is modulated by parameters such as (1) exposure time with rare longer term experiments revealing negative impacts that are hidden in short or midterm ones; (2) bottlenecks in physiological processes and life-cycle such as stage-specific developmental phenomena that may drive the whole species responses; (3) ecological feedback transforming small scale sub lethal effects into important negative effects on fitness. We hypothesize that populations/species naturally exposed to variable environmental pH conditions may be pre-adapted to future OA highlighting the importance to understand and monitor environmental variations in order to be able to to predict sensitivity to future climate changes. More stress ecology research is needed at the frontier between ecotoxicology and ecology, going beyond standardized tests using model species in order to address multiple water quality factors (e.g. pH, temperature, toxicants) and organism health. However, available data allow us to conclude that near-future OA will have negative impact on echinoderm taxa with likely significant consequences at the ecosystem level.

Pear psylla, Cacopsylla pyricola (Förster), is the most economically challenging pest of commercial pears in Washington and Oregon, the top producers of pears in the United States. The objective of this study was to quantify economic injury levels and thresholds for pear psylla. We used the relationship between pear psylla adult and nymph densities, and fruit downgraded due to psylla honeydew marking to identify injury levels. We calculated economic injury levels using the cost of downgraded fruit and average management costs (spray materials and labor). Using economic injury levels, we determined economic thresholds for pear psylla, which include predicted pest population growth, natural enemy predation, and anticipated delays between when pest populations are measured and when managers apply interventions. Economic thresholds generated by this study were 0.1–0.3 second-generation nymphs per leaf and 0.2–0.8 third-generation nymphs per leaf depending on predicted price and yield for insecticide applications at 1,300 pear psylla degree days in the second generation and 2,600 pear psylla degree days in the third generation. Natural enemy inaction thresholds identified by this study were 6 Deraeocoris brevis or 3 Campylomma verbasci immatures per 30 trays or 2 earwigs per trap for third-generation optional insecticide applications.

Behavioral differences between men and women have been studied extensively, as have differences in brain anatomy. However, most studies have focused on differences in gray matter, while white matter has been much less studied. We conducted a comprehensive study of 77 deep white matter tracts to analyze their volumetric and microstructural variability between men and women in the full Human Connectome Project (HCP) cohort of 1065 healthy individuals aged 22–35 years. We found a significant difference in total brain volume between men and women (+ 12.6% in men), consistent with the literature. 16 tracts showed significant volumetric differences between men and women, one of which stood out due to a larger effect size: the corpus callosum genu, which was larger in women (+ 7.3% in women, p = 5.76 × 10 –19 ). In addition, we found several differences in microstructural parameters between men and women, both using standard Diffusion Tensor Imaging (DTI) parameters and more complex microstructural parameters from the Neurite Orientation Dispersion and Density Imaging (NODDI) model, with the tracts showing the greatest differences belonging to motor (cortico-spinal tracts, cortico-cerebellar tracts) or limbic (cingulum, fornix, thalamo-temporal radiations) systems. These microstructural differences may be related to known behavioral differences between the sexes in timed motor performance, aggressiveness/impulsivity, and social cognition.

Health anxiety is an under-recognised but a frequent cause of distress. It is particularly common in general hospitals. We carried out an 8-year follow-up of medical out-patients with health anxiety (hypochondriasis) enrolled in a randomised-controlled trial in five general hospitals in London, Middlesex and Nottinghamshire. Randomisation was to a mean of six sessions of cognitive behaviour therapy adapted for health anxiety (CBT-HA) or to standard care in the clinics. The primary outcome was a change in score on the Short Health Anxiety Inventory, with generalised anxiety and depression as secondary outcomes. Of 444 patients aged 16-75 years seen in cardiology, endocrinology, gastroenterology, neurology and respiratory medicine clinics, 306 (68.9%) were followed-up 8 years after randomisation, including 36 who had died. The study is registered with controlled-trials.com, ISRCTN14565822. There was a significant difference in the HAI score in favour of CBT-HA over standard care after 8 years [1.83, 95% confidence interval (CI) 0.25-3.40, p = 0.023], between group differences in generalised anxiety were less (0.54, 95% CI -0.29 to 1.36), p = 0.20, ns), but those for depression were greater at 8 years (1.22, 95% CI 0.42-2.01, p < 0.003) in CBT-HA than in standard care, most in standard care satisfying the criteria for clinical depression. Those seen by nurse therapists and in cardiology and gastrointestinal clinics achieved the greatest gains with CBT-HA, with greater improvement in both symptoms and social function. CBT-HA is a highly long-term effective treatment for pathological health anxiety with long-term benefits. Standard care for health anxiety in medical clinics promotes depression. Nurse therapists are effective practitioners.

Recent work has demonstrated that children with unintentional cannabis ingestions often undergo extensive ancillary testing such as head imaging or lumbar puncture. To better understand the yield of these tests, our objective was to describe the frequency of additional significant diagnoses in children with cannabis ingestion. We performed a retrospective cross-sectional study of the Pediatric Health Information System (PHIS) database, including ED encounters from January 2016 to April 2023 with a diagnosis indicating cannabis exposure in children <6 years of age. We assessed the frequency of co-diagnoses that would be found on head imaging, lumbar puncture, or toxicology testing. We included 4132 ED encounters for cannabis ingestion from 47 hospitals. Of these, 1243 (30%) received head imaging and 130 (3.1%) underwent lumbar puncture. There were 23 children (0.6%) with diagnosis of skull fracture or intracranial hemorrhage, 4 (<0.1%) with intracranial neoplasm, and 0 (0%) with a diagnosis for meningitis or intracranial abscess. Presence of discharge diagnosis for other drugs was also uncommon. The most frequent drug ingestion co-diagnoses were cocaine in 43 (1.0%) and opioids in 22 (0.5%) encounters. In children with cannabis intoxication, high rates of head imaging and lumbar puncture are likely driven by the signs of altered mental status at presentation. These data suggest that if cannabis ingestion is considered early and identified quickly with testing, neuroimaging, particularly that with ionizing radiation, may be low yield.

Momentum and scalar (heat and water vapor) transfer between a walnut canopy and the overlying atmosphere are investigated for two seasonal periods (before and after leaf-out), and for five thermal stability regimes (free and forced convection, near-neutral condition, transition to stable, and stable). Quadrant and octant analyses of momentum and scalar fluxes followed by space-time autocorrelations of observations from the Canopy Horizontal Array Turbulence Study's (CHATS) thirty meter tower help characterize the motions exchanging momentum, heat, and moisture between the canopy layers and aloft. During sufficiently windy conditions, i.e. in forced convection, near-neutral and transition to stable regimes, momentum and scalars are generally transported by sweep and ejection motions associated with the well-known canopy-top \"shear-driven\" coherent eddy structures. During extreme stability conditions (both unstable and stable), the role of these \"shear-driven\" structures in transporting scalars decreases, inducing notable dissimilarity between momentum and scalar transport. In unstable conditions, \"shear-driven\" coherent structures are progressively replaced by \"buo-yantly-driven\" structures, known as thermal plumes; which appear very efficient at transporting scalars, especially upward thermal plumes above the canopy. Within the canopy, downward thermal plumes become more efficient at transporting scalars than upward thermal plumes if scalar sources are located in the upper canopy. We explain these features by suggesting that: (i) downward plumes within the canopy correspond to large downward plumes coming from above, and (ii) upward plumes within the canopy are local small plumes induced by canopy heat sources where passive scalars are first injected if there sources are at the same location as heat sources. Above the canopy, these small upward thermal plumes aggregate to form larger scale upward thermal plumes. Furthermore, scalar quantities carried by downward plumes are not modified when penetrating the canopy and crossing upper scalar sources. Consequently, scalars appear to be preferentially injected into upward thermal plumes as opposed to in downward thermal plumes. In stable conditions, intermittent downward and upward motions probably related to elevated shear layers are responsible for canopy-top heat and water vapor transport through the initiation of turbulent instabilities, but this transport remains small. During the foliated period, lower-canopy heat and water vapor transport occurs through thermal plumes associated with a subcanopy unstable layer.