Explore the vast range of titles available.

Tree mortality rates appear to be increasing in moist tropical forests (MTFs) with significant carbon cycle consequences. Here, we review the state of knowledge regarding MTF tree mortality, create a conceptual framework with testable hypotheses regarding the drivers, mechanisms and interactions that may underlie increasing MTF mortality rates, and identify the next steps for improved understanding and reduced prediction. Increasing mortality rates are associated with rising temperature and vapor pressure deficit, liana abundance, drought, wind events, fire and, possibly, CO2 fertilization-induced increases in stand thinning or acceleration of trees reaching larger, more vulnerable heights. The majority of these mortality drivers may kill trees in part through carbon starvation and hydraulic failure. The relative importance of each driver is unknown. High species diversity may buffer MTFs against large-scale mortality events, but recent and expected trends in mortality drivers give reason for concern regarding increasing mortality within MTFs. Models of tropical tree mortality are advancing the representation of hydraulics, carbon and demography, but require more empirical knowledge regarding the most common drivers and their subsequent mechanisms. We outline critical datasets and model developments required to test hypotheses regarding the underlying causes of increasing MTF mortality rates, and improve prediction of future mortality under climate change.

To describe differences in bone outcomes according to biological age in male athletes participating in osteogenic (OS) or non-osteogenic (NOS) sports. Longitudinal (12-months). 104 adolescents (12–14years) were measured at baseline and after 1y: OS group (n=37 football or soccer players) and NOS group (n=39 swimmers, n=28 cyclists). Years from peak height velocity (PHV, −2 to +2) was used as a maturational landmark. Bone mineral content (BMC) was assessed using DXA. Hip structural analysis estimated cross-sectional area (CSA), cross-sectional moment of inertia (CSMI) and section modulus (Z) at the femoral neck (FN). Trabecular bone score (TBS) estimated lumbar spine (LS) texture. Quantitative ultrasound measured bone stiffness. Multilevel regression models adjusted by hours of training were fitted. Compared to NOS, OS had significantly greater total body (less head) BMC from PHV to +2years from PHV (from 9.5% to 11.3%, respectively); LS BMC from −1years from PHV to PHV (from 9.8% to 9.9%); hip BMC (from 11.6% to 22.9%), FN BMC (from 12.0% to 15.9%), TBS (from 4.2% to 4.8%) and stiffness index (from 11.9% to 23.3%) from −1years from PHV to +2years from PHV; and CSA (from 8.4% to 18.8%), Z (from 5.5% to 22.9%) and CSMI (from 10.6% to 23.3%) from −2years from PHV to +2years from PHV. There was a significant trend for the between-group differences to increase with biological age except for LS BMC and TBS. These findings underline the differential bone response to different sports throughout the years surrounding PHV in male adolescent athletes. Clinical trial registration: ISRCTN17982776.