The influence of plant diversity on slope stability was investigated at early phases of succession in a mixed forest in Sichuan, China. The first phase comprised big node bamboo (
Phyllostachys ...nidularia Munro) only. In the second phase, bamboo co-existed with deciduous tree species and in the third phase, deciduous species existed alone. Root density at different depths and root tensile strength were determined for each species. The factor of safety (FOS) was calculated for slopes with and without vegetation for each succession phase. For phase 2, FOS was determined for different species mixtures and positions. In phase 3, simulations were performed with a single tree at the top, middle or toe of the slope. Due to its shallow root system, bamboo contributed little to slope stability. In simulations with the tree at the top or middle of the slope, FOS decreased because tree weight added a surcharge to the slope. FOS increased with the tree at the bottom of the slope. Different mixtures of species along the slope had no influence on FOS. Differences in root tensile strength between species played a small role in FOS calculations, and tree size and density were the most important factors affecting slope stability, excluding hydrological factors.
Highway embankments and cutting slopes in the United Kingdom, particularly in the South East of England, are often constructed of or within stiff over-consolidated clays. These clays are prone to ...softening with time leading to shallow slope failures and costly repairs. Reinforcement by natural vegetation is potentially a cost-effective method of stabilising these types of slopes over the medium–long term. However, there is a lack of information on how natural vegetation reinforces and stabilises clay slopes. To investigate this problem, the potential reinforcement of selected oak (Quercus robur L.) and hawthorn (Crataegus monogyna Jacq.) roots was assessed by conducting in situ root pull-out experiments on a London Clay cutting in south-east England. Pull-out tests were carried out using specifically designed clamps and either a hand pull system with a spring balance and manual recording of force for oak roots or a jacking system with electronic data logging of applied force and displacement for hawthorn roots. Oak roots had a mean pull-out resistance of 7 MPa and that of hawthorn roots was 8 MPa. The electronic data logging of applied force (pull-out resistance) and displacement of the hawthorn roots provided additional data on the failure of branched roots which could be correlated with variations in root morphology. The failure of the roots can be categorised into three modes: Type A: single root failure with rapid rise in pull-out resistance until failure occurs; Type B: double peak failure of a forked or branched root and Type C: stepped failure with multiple branches failing successively. The different types of root-soil bonds are described in relation to root anchorage and soil stability.
Purpose
This report describes the development and dissemination of a library of English measures, with Spanish translations, on constructs relevant to social determinants of health and behavioral ...health outcomes. The El Centro Measures Library is a product of the Center of Excellence for Health Disparities Research: El Centro, a program funded by the National Institute on Minority Health and Health Disparities of the U.S. National Institutes of Health. The library is aimed at enhancing capacity for minority health and health disparities research, particularly for Hispanics living in the United States and abroad.
Design
The open‐access library of measures (available through www.miami.edu/sonhs/measureslibrary) contains brief descriptions of each measure, scoring information (where available), links to related peer‐reviewed articles, and measure items in both languages. Links to measure websites where commercially available measures can be purchased are included, as is contact information for measures that require author permission. Links to several other measures libraries are hosted on the library website. Other researchers may contribute to the library.
Methods
El Centro investigators began the library by electing to use a common set of measures across studies to assess demographic information, culture‐related variables, proximal outcomes of interest, and major outcomes. The collection was expanded to include other health disparity research studies. In 2012, a formal process was developed to organize, expand, and centralize the library in preparation for a gradual process of dissemination to the national and international community of researchers.
Findings
The library currently contains 61 measures encompassing 12 categories of constructs. Thus far, the library has been accessed 8,883 times (unique page views as generated by Google Analytics), and responses from constituencies of users and measure authors have been favorable.
Clinical Relevance
With the paucity of availability and accessibility of translated measures, behavioral nursing research focused on reducing health disparities can benefit from repositories of research instruments such as the El Centro Measures Library.
This book is designed to assist the civil and geotechnical engineer, geomorphologist, forester, landscape architect or ecologist in choosing ecotechnological solutions for slopes that are prone to a ...variety of mass movements e.g. shallow failure or erosion. Within this book, the ‘engineer’ is used in the global sense to encompass all planners, designers, etc. who are involved in the stabilisation of slopes. We review the types of problematic slopes that may occur and describe briefly the nature of mass movements and the causes of these movements. In this book, we focus on the use of vegetation to stabilize soil on slopes prone to mass movements. Before a plant can be chosen for a particular function, its physical and hydrological properties must be determined, thus the root architecture of grasses, shrubs and trees are described and the soil hydrological and mechanical factors which influence vegetation are discussed. Depending on the use of the slope, the engineer may wish to ascertain either the stability of the slope or the mechanical stability of the vegetation or both, therefore slope stability analysis methods are reviewed and the contribution the vegetation has to the stability of the slope are explained. Models to assess the mechanical stability of vegetation are reviewed. This book also introduces new ecotechnological methods for stabilising active rockfalls on steep slopes and slopes that are prone to soil erosion following wild fires, as well as providing user friendly information on traditional ground bio-engineering techniques and tables of plants suitable for different functions. Case studies where ground bio- and eco-engineering measures have been put into practice are also discussed.
Summary
Family‐based methods are a potentially powerful tool to identify trait‐defining genetic variants in extended families, particularly when used to complement conventional association analysis. ...We utilized two‐point linkage analysis and single variant association analysis to evaluate whole exome sequencing (WES) data from 1205 Hispanic Americans (78 families) from the Insulin Resistance Atherosclerosis Family Study. WES identified 211,612 variants above the minor allele frequency threshold of ≥0.005. These variants were tested for linkage and/or association with 50 cardiometabolic traits after quality control checks. Two‐point linkage analysis yielded 10,580,600 logarithm of the odds (LOD) scores with 1148 LOD scores ≥3, 183 LOD scores ≥4, and 29 LOD scores ≥5. The maximal novel LOD score was 5.50 for rs2289043:T>C, in UNC5C with subcutaneous adipose tissue volume. Association analysis identified 13 variants attaining genome‐wide significance (P < 5 × 10−08), with the strongest association between rs651821:C>T in APOA5 and triglyceride levels (P = 3.67 × 10−10). Overall, there was a 5.2‐fold increase in the number of informative variants detected by WES compared to exome chip analysis in this population, nearly 30% of which were novel variants relative to the Database of Single Nucleotide Polymorphisms (dbSNP) build 138. Thus, integration of results from two‐point linkage and single‐variant association analysis from WES data enabled identification of novel signals potentially contributing to cardiometabolic traits.
The procedure for geotechnical site investigation is well established but little attention is currently given to investigating the potential of vegetation to assist with ground stability. This paper ...describes how routine investigation procedures may be adapted to consider the effects of the vegetation. It is recommended that the major part of the vegetation investigation is carried out, at relatively low cost, during the preliminary (desk) study phase of the investigation when there is maximum flexibility to take account of findings in the proposed design and construction. The techniques available for investigation of the effects of vegetation are reviewed and references provided for further consideration. As for general geotechnical investigation work, it is important that a balance of effort is maintained in the vegetation investigation between (a) site characterisation (defining and identifying the existing and proposed vegetation to suit the site and ground conditions), (b) testing (in-situ and laboratory testing of the vegetation and root systems to provide design parameters) and (c) modelling (to analyse the vegetation effects).
These proceedings bring together papers from geotechnical and civil engineers, biologists, ecologists and foresters who discuss current problems in slope stability research, and how to address those ...problems using ground bio- and eco-engineering techniques.
In an era where climate change, natural catastrophes and land degradation are major issues, the conservation of soil and vegetation in mountainous or sloping regions has become an international ...priority. How to avoid substrate mass movement through landslides and erosion using sustainable and ecologically sound techniques is rapidly becoming a scientific domain where knowledge from many different fields is required. These proceedings bring together papers from geotechnical and civil engineers, biologists, ecologists and foresters, who discuss current problems in slope stability research, and how to address those problems using ground bio- and eco-engineering techniques. Ground bioengineering methods integrate civil engineering techniques with natural materials to obtain fast, effective and economic methods of protecting, restoring and maintaining the environment whereas eco-engineering has been defined as a long-term ecological strategy to manage a site with regard to natural or man-made hazards. Studies on slope instability, erosion, soil hydrology, mountain ecology, land use and restoration and how to mitigate these problems using vegetation are presented by both scientists and practitioners. Papers encompass many aspects of this multidisciplinary subject, including the mechanisms and modelling of root reinforcement and the development of decision support systems, areas where significant advances have been made in recent years.
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