Do looks matter? A case study on extensive green roofs using discrete choice experiments

Extensive green roofs are a promising type of urban green that can play an important role in climate proofing and ultimately in the sustainability of our cities. Despite their increasingly widespread application and the growing scientific interest in extensive green roofs, their aesthetics have received limited scientific attention. Furthermore, several functional issues occur, as weedy species can colonize the roof, and extreme roof conditions can lead to gaps in the vegetation. Apart from altering the function of a green roof, we also expect these issues to influence the perception of extensive green roofs, possibly affecting their acceptance and application. We therefore assessed the preferences of a self-selected convenience sample of 155 Flemish respondents for visual aspects using a discrete choice experiment. This approach, combined with current knowledge on the psychological aspects of green roof visuals, allowed us to quantify extensive green roof preferences. Our results indicate that vegetation gaps and weedy species, together with a diverse vegetation have a considerable impact on green roof perception. Gaps were the single most important attribute, indicated by a relative importance of ca. 53%, with cost coming in at a close second at ca. 46%. Overall, this study explores the applicability of a stated preference technique to assess an often overlooked aspect of extensive green roofs. It thereby provides a foundation for further research aimed at generating practical recommendations for green roof construction and maintenance

Global-scale characterization of turning points in arid and semi-arid ecosystem functioning

Aim: Changes in dryland ecosystem functioning are threatening the well‐being of human populations worldwide, and land degradation, exacerbated by climate change, contributes to biodiversity loss and puts pressures on sustainable livelihoods. Here, abrupt changes in ecosystem functioning [so‐called turning points (TPs)] were detected using time series of Earth observation data. Hotspot areas of high TP occurrence were identified, observed changes characterized and insights gained on potential drivers for these changes.Location: Arid and semi‐arid regions.Time period: 1982–2015.Methods: We used a time series segmentation technique (breaks for additive season and trend) to detect breakpoints in rain‐use efficiency as a means of analysing changes in ecosystem functioning. A new typology to characterize the detected changes was proposed and evaluated, at regional to local scales, for a set of case studies. Ancillary data on population and drought were used to provide insights on potential drivers of TP occurrence.Results: Turning points in ecosystem functioning were found in 13.6% (c. 2.1 × 106 km2) of global drylands. Turning point hotspots were primarily observed in North America, the Sahel, Central Asia and Australia. In North America, the majority of TPs (62.6%) were characterized by a decreasing trend in ecosystem functioning, whereas for the other regions, a positive reversal in ecosystem functioning was prevalent. Further analysis showed that: (a) both climatic and anthropogenic pressure influenced the occurrence of TPs in North America; (b) Sahelian grasslands were primarily characterized by drought‐induced TPs; and (c) high anthropogenic pressure coincided with the occurrence of TPs in Asia and Australia.Main conclusions: By developing a new typology targeting the categorization of abrupt and gradual changes in ecosystem functioning, we detected and characterized TPs in global drylands. This TP characterization is a first crucial step towards understanding the drivers of change and supporting better decision‐making for ecosystem conservation and management in drylands

Conventional versus direct magnetic resonance imaging in detecting labral lesions in femoroacetabular impingment - a retrospective multicenter study.

The purpose of this study was to assess the reliability of Direct Magnetic Resonance Arthography (MRA) and Conventional Magnetic Resonance Imaging (MRI) in diagnosing labral lesions in patients with symptoms of femoroacetabular impingement (FAI). Materials and methods: Imaging and surgical data (n=490) were retrospectively collected from 5 high-volume centres providing arthroscopic treatment of FAI patients. Preoperative magnetic resonance imaging findings were compared with the actual surgical findings regarding labral condition in order to assess the effectiveness of MRI and MRA in identifying the presence of labral tears in patients with FAI. The results of this study indicate that MM and MRA may both be useful for the diagnosis of acetabular labral lesions. The accuracy is slightly higher for MRI (71,4 %) compared to MRA (68,2 %), although MRA has higher sensitivity (74.4%,) as compared to MRI (66,9%). Conclusions: In a clinically suspected labral tear MRA has higher sensitivity than MRI. Further studies on asymptomatic patients may be needed to determine the specificity of different MRI techniques

Six-dimensional quasiclassical and quantum dynamics of H2 dissociation on the c(2 * 2)-Ti/Al(100) surface

The following article appeared in Journal of Chemical Physic 134.11 (2011): 114708 and may be found at http://scitation.aip.org/content/aip/journal/jcp/134/11/10.1063/1.3567397Based on a slab model of H2 dissociation on a c(2 * 2) structure with Ti atoms in the first and third layers of Al(100), a six-dimensional (6D) potential energy surface (PES) has been built. In this PES, a molecular adsorption well with a depth of 0.45 eV is present in front of a barrier of height 0.13 eV. Using this PES, H2 dissociation probabilities are calculated by the classical trajectory (CT), the quasiclassical trajectory (QCT), and the time-dependent wave-packet (TDWP) method. The QCT study shows that trajectories can be trapped by the molecular adsorption well. Higher incident energy can lead to direct H2 dissociation. Vibrational pre-excitation is the most efficient way to promote direct dissociation without trapping. We find that both rotational and vibrational excitation have efficacies close to 1.0 in the entire range of incident energies investigated, which supports the randomization in the initial conditions making the reaction rate solely dependent on the total (internal and translational) energy. The H2 dissociation probabilities from quantum dynamics are in reasonable agreement with the QCT results in the energy range 50-200 meV, except for some fluctuations. However, the TDWP results considerably exceed the QCT results in the energy range 200-850 meV. The CT reaction probabilities are too low compared with the quantum dynamical resultsThe research of J.C.C. is supported by the Marie Curie Research Training Network HYDROGE

A review of community-based natural resource management

Please read abstract in article.http://www.aloki.huam2018Centre for Wildlife ManagementMammal Research Institut

Inadequate community engagement hamstrings sustainable wildlife resource management in Zambia

We propose improvements for addressing the inadequate sustainable use of wildlife resources in the community‐based natural resource management (CBNRM) programme in game management areas (GMAs) using case study data from Mumbwa and Lupande GMAs in Zambia. Firstly, we assess the sustainability of wildlife resources in these GMAs using design principles for enduring common pool institutions. Secondly, we propose the steps required to address the lack of sustainability of wildlife resources in the CBNRM programme in the two GMAs by building on indicators suggested by Ostrom's principles. The resource use patterns in the two GMAs were assessed according to their socio‐economic and institutional factors. Comparisons were made between the two GMAs in relation to Ostrom's design principles. Accordingly, the combination of socio‐economic and institutional factors restrains the sustainable use of wildlife resources in the two GMAs. Unless the Zambian government provides local communities with meaningful decision‐making powers and benefits for the utilisation and management of wildlife, this resource is likely to disappear outside national parks.The STRECC Programme of Maastricht University in the Netherlands and the Association of African Universities in Ghana. Michael John Somers also thanks the National Research Fund (NRF) Incentive Fund.https://wileyonlinelibrary.com/journal/aje2020-07-27hj2019Centre for Wildlife ManagementMammal Research Institut

Uncovering Dryland Woody Dynamics Using Optical, Microwave, and Field Data—Prolonged Above-Average Rainfall Paradoxically Contributes to Woody Plant Die-Off in the Western Sahel

Dryland ecosystems are frequently struck by droughts. Yet, woody vegetation is often able to recover from mortality events once precipitation returns to pre-drought conditions. Climate change, however, may impact woody vegetation resilience due to more extreme and frequent droughts. Thus, better understanding how woody vegetation responds to drought events is essential. We used a phenology-based remote sensing approach coupled with field data to estimate the severity and recovery rates of a large scale die-off event that occurred in 2014–2015 in Senegal. Novel low (L-band) and high-frequency (Ku-band) passive microwave vegetation optical depth (VOD), and optical MODIS data, were used to estimate woody vegetation dynamics. The relative importance of soil, human-pressure, and before-drought vegetation dynamics influencing the woody vegetation response to the drought were assessed. The die-off in 2014–2015 represented the highest dry season VOD drop for the studied period (1989–2017), even though the 2014 drought was not as severe as the droughts in the 1980s and 1990s. The spatially explicit Die-off Severity Index derived in this study, at 500 m resolution, highlights woody plants mortality in the study area. Soil physical characteristics highly affected die-off severity and post-disturbance recovery, but pre-drought biomass accumulation (i.e., in areas that benefited from above-normal rainfall conditions before the 2014 drought) was the most important variable in explaining die-off severity. This study provides new evidence supporting a better understanding of the “greening Sahel”, suggesting that a sudden increase in woody vegetation biomass does not necessarily imply a stable ecosystem recovery from the droughts in the 1980s. Instead, prolonged above-normal rainfall conditions prior to a drought may result in the accumulation of woody biomass, creating the basis for potentially large-scale woody vegetation die-off events due to even moderate dry spells

EORTC Group Phase II Study of Oral Etoposide for Pretreated Soft Tissue Sarcoma

Purpose. This study investigates the efficacy and toxicity of daily oral etoposide in chemotherapy for non-heavily pretreated advanced and metastatic soft tissue sarcoma (STS)

Are we sinking African cheetahs in India?

SIGNIFICANCE : The current initiative to export African cheetahs to India has a limited scientific basis, placing the Asian subspecies and the translocated animals at risk. There is no evidence that this will benefit African cheetah conservation. We call for a globally coordinated approach to cheetah conservation, based on sound science.http://www.sajs.co.zahj2023Mammal Research InstituteZoology and Entomolog