Judging where a ball will go: the case of curved free kicks in football

This study examined whether adding spin to a ball in the free kick situation in football affects a professional footballer’s perception of the ball’s future arrival position. Using a virtual reality set-up, participants observed the flight paths of aerodynamically realistic free kicks with (±600 rpm) and without sidespin. With the viewpoint being fixed in the centre of the goal, participants had to judge whether the ball would have ended up in the goal or not. Results show that trajectories influenced by the Magnus force caused by sidespin gave rise to a significant shift in the percentage of goal responses. The resulting acceleration that causes the ball to continually change its heading direction as the trajectory unfolds does not seem to be taken into account by the participants when making goal judgments. We conclude that the visual system is not attuned to such accelerated motion, which may explain why goalkeepers appear to misjudge the future arrival point of such curved free kicks. Electronic Supplementary Material  Supplementary material is available for this article at .     

Holocene forest development and maintenance on different substrates in the Klamath Mountains, northern California, USA

The influence of substrate on long-term vegetation dynamics has received little attention, and yet nutrient-limited ecosystems have some of the highest levels of endemism in the world. The diverse geology of the Klamath Mountains of northern California (USA) allows examination of the long-term influence of edaphic constraints in subalpine forests through a comparison of vegetation histories between nutrient-limited ultramafic substrates and terrain that is more fertile. Pollen and charcoal records spanning up to 15000 years from ultramafic settings reveal a distinctly different vegetation history compared to other soil types. In non-ultramafic settings, the dominant trees and shrubs shifted in elevation in response to Holocene climate variations resulting in compositional and structural changes, whereas on ultramafic substrates changes were primarily structural, not compositional. Fire activity was similar through most of the Holocene with the exception of declines over the last 4000 years on ultramafic substrates, likely due to the reduction of understory fuels and cooler wetter conditions than in the middle Holocene. These results suggest that the tree and shrub distributions were more responsive to past climate changes on non-ultramafic substrates compared to those on ultramafic substrates. The combination of these dynamics may help explain high levels of plant diversity in the Klamath Mountains and provide insights for managing these complex ecosystems.     

Simulating Historical Variability in the Amount of Old Forests in the Oregon Coast Range

Abstract: We developed the landscape age-class demographics simulator ( LADS) to model historical variability in the amount of old-growth and late-successional forest in the Oregon Coast Range over the past 3,000 years. The model simulated temporal and spatial patterns of forest fires along with the resulting fluctuations in the distribution of forest age classes across the landscape. Parameters describing historical fire regimes were derived from data from a number of existing dendroecological and paleoecological studies. Our results indicated that the historical age-class distribution was highly variable and that variability increased with decreasing landscape size. Simulated old-growth percentages were generally between 25% and 75% at the province scale (2,250,000 ha) and never fell below 5%. In comparison, old-growth percentages varied from 0 to 100% at the late-successional reserve scale (40,000 ha). Province-scale estimates of current old-growth (5%) and late-successional forest (11%) in the Oregon Coast Range were lower than expected under the simulated historical fire regime, even when potential errors in our parameter estimates were considered. These uncertainties do, however, limit our ability to precisely define ranges of historical variability. Our results suggest that in areas where historical disturbance regimes were characterized by large, infrequent fires, management of forest age classes based on a range of historical variability may be feasible only at relatively large spatial scales. Comprehensive landscape management strategies will need to consider other factors besides the percentage of old forests on the landscape, including the spatial pattern of stands and the rates and pathways of landscape change.     

The use of material flow analysis and the ecological footprint in regional policy-making: application and insights from Northern Ireland

This paper aims to contribute to the ongoing debate on the use of resource accounting tools in regional policy-making. The Northern Limits project applied material flow analysis (MFA) and ecological footprinting (EF) to regional policy-making in Northern Ireland over a number of years. The early phase of the research informed the regions first sustainable development strategy which was published in 2006 with key targets relating to the EF and improving the resource efficiency of the economy. Phase II identified the next steps required to address data availability and quality and the use of MFA and EF in providing a measurement and monitoring framework for the strategy and the development of the strategy implementation plan. The use of MFA and EF in sustainable regional policy-making and the monitoring of its implementation is an ongoing process which has raised a number of research issues which can inform the ongoing application and development of these and other resource accounting tools to within Northern Ireland, provide insights for their use in other regions, and help set out the priorities for research to support this important policy area.     

Extended bioremediation of PAH/PCP contaminated soils from the POPILE wood treatment facility

A study was conducted using two pilot-scale land-treatment units (LTUs) to evaluate the efficacy of different cultivation and maintenance schedules during bioremediation of contaminated soil from a wood treatment facility using landfarming technology. The soil contained high concentrations of polycyclic aromatic hydrocarbons (PAHs, approximately 13000 ppm) as well as of pentachlorophenol (PCP, approximately 1500 ppm). An initial 6-month intensive-treatment phase was followed by 24 months of less-intensive treatment. During the first phase, traditional landfarming practice of regular cultivation was compared with a gas-phase composition based cultivation strategy, and both the landfarming units were intensively monitored and maintained with respect to moisture control and delivery of nutrients. The two strategies resulted in similar contaminant concentration profiles with time during this phase, although different microbial populations developed in the two-landfarming units. The second (less-intensive) treatment phase involved no moisture control and nutrient delivery beyond the initial adjustments, and compared natural attenuation (no cultivation) with quarterly cultivation of soil. Both the strategies showed similar behavior again. GC/MS analysis of the soil samples showed PAH removal including four-ring homologues. Leachability tests at zero time and after 6 and 22 months of operation showed significant reductions in leaching of PCP and low molecular weight PAHs. Extended treatment resulted in some leaching of high molecular weight PAHs. Significant biological activity was demonstrated, even at the high contaminant concentrations. Phospholipid ester-linked fatty acid (PLFA) analysis showed an increase in biomass and a divergence in community composition in soils depending on the treatment conducted.     

Diagnosis of polyhydramnios in early gestation: Indication for prenatal diagnosis?

Previously published reports have indicated that idiopathic polyhydramnios may be associated with trisomies 18 and 21 and that chromosomal analysis is indicated. Furthermore, the natural history and fetal outcome of polyhydramnios diagnosed in early gestation have not been well delineated. We identified 138 pregnancies with polyhydramnios prior to 26 weeks' gestation. Of 131 complete cases, 21 were diagnosed as severe, 18 as moderate, and 92 as mild polyhydramnios. Congenital abnormalities were noted in 18 of 21 severe cases (86 per cent). Two of the remaining three cases were twin-to-twin transfusion. Thirteen of 18 cases with moderate polyhydramnios (72 per cent) were associated with anomalies; six of the remaining cases were twin-to-twin transfusion. Sixteen of 92 cases of mild polyhydramnios (17 per cent) were associated with congenital abnormalities. In 69 of 76 cases of mild hydramnios not associated with anomalies (91 per cent), the hydramnios resolved prior to delivery. Only 2 of 16 (13 per cent) associated with anomalies resolved. In 4 of 5 cases (80 per cent) with moderate hydramnios and no anomalies, the amniotic fluid volume was normal on subsequent ultrasound. No case of moderate polyhydramnios associated with anomalies or maternal conditions nor any case of severe polyhydramnios resolved. There were seven cases of chromosomal abnormalities in this series; all were associated with sonographic findings in addition to the presence of polyhydramnios. On the basis of these data, we doubt the benefit of amniocentesis following the early diagnosis of idiopathic polyhydramnios in the absence of other ultrasound findings.     

Analysing countries’ contribution to climate change: scientific and policy-related choices

This paper evaluates the influence of different policy-related and scientific choices on the calculated regional contributions to global climate change (the “Brazilian Proposal”). Policy-related choices include the time period of emissions, the mix of greenhouse gases and different indicators of climate change impacts. The scientific choices include historical emissions and model representations of the climate system. We generated and compared results of several simple climate models. We find that the relative contributions of different nations to global climate change—from emissions of greenhouse gases alone—are quite robust, despite the varying model complexity and differences in calculated absolute changes. For the default calculations, the average calculated contributions to the global mean surface temperature increase in 2000 are about 40% from OECD, 14% from Eastern Europe and Former Soviet Union, 24% from Asia and 22% from Africa and Latin America. Policy-related choices, such as time period of emissions, climate change indicator and gas mix generally have larger influence on the results than scientific choices. More specifically, choosing a later attribution start date (1990 instead of 1890) for historical emissions, decreases the contributions of regions that started emitting early, such as the OECD countries by 6 percentage points, whereas it increases the contribution of late emitters such as Asia by 8 percentage points. However, only including the fossil CO₂ emissions instead of the emissions of all Kyoto gases (fossil and land use change), increases the OECD contributions by 21 percentage points and decreases the contribution of Asia by 14 percentage points.     

PCBs and DDT in the serum of juvenile California sea lions: associations with vitamins A and E and thyroid hormones

In order to better understand the fate of metals during the biodegradation of organic matter in soils, an in vitro incubation experiment was conducted with metal-rich and metal-free leaves of Arabidopsis halleri introduced in a non-contaminated soil. During incubation of these microcosms, we followed the partitioning of Zn and Cd between the solution and their solid components, by determining the metal contents of six soil fractions and dissolved metals after granulo-densimetric separations at selected times. Microbial biomass and exchangeable metals in K(2)SO(4) solutions were also determined at the same times, and two main stages were identified. The first one takes place after a fast abiotic transfer of Zn and Cd from readily soluble plant tissues onto fine soil constituents, keeping metals away from the liquid phase: during about 14 days, microbial biomass increased as well as metal contents of some soil fractions, particularly those rich in particulate organic matter. During the second stage, between 14 and 60 days and for the metal-rich microcosms, Zn and Cd contents in solution increased, while microbial biomass decreased instead of staying constant as in control. A change of Zn and Cd speciation is assumed, from non-toxic adsorbed forms to more toxic species in solution. Remaining metal-rich plant residues seem to create a stable organic C compartment in the soil.