An Assessment of the Potential Economic Impacts of the Invasive Polyphagous Shot Hole Borer (Coleoptera: Curculionidae) in South Africa.

Studies addressing the economic impacts of invasive alien species are biased towards ex-post assessments of the costs and benefits of control options, but ex-ante assessments are also required to deal with potentially damaging invaders. The polyphagous shot hole borer Euwallacea fornicatus (Coleoptera: Curculionidae) is a recent and potentially damaging introduction to South Africa. We assessed the potential impact of this beetle by working across economic and biological disciplines and developing a simulation model that included dynamic mutualistic relations between the beetle and its symbiotic fungus.

Investing in natural capital and national security: A comparative review of restoration projects in South Africa.

Does restoration pay? We seek to answer this question by reviewing the benefits and costs of 37 economic values derived from five groups of actual restoration-related case studies in South Africa at various scales. The mean opportunity costs of not restoring are the following (a negative value implies an economic loss to society): i) local level single species studies concerned with clearing invasive alien plants (mean = -$27.24/ha/yr, sd = +/-22.

An investigation to elucidate the factors dictating the crystal structure of seven ammonium carboxyl-ate mol-ecular salts.

The crystal structures of seven ammonium carboxyl-ate salts are reported, namely ()-1-phenyl-ethan-1-aminium isonicotinate, CHN·CHNO, (I), ()-1-phenyl-ethan-1-aminium flurbiprofenate [or 2-(3-fluoro-4-phenyl-phen-yl)propano-ate], CHN·CHFO, (II), ()-1-phenyl-ethan-1-aminium 2-chloro-4-nitro-benzoate, CHN·CHClNO, (III), ()-1-phenyl-ethan-1-aminium 4-iodo-benzoate, CHN·CHIO, (IV), ()-1-cyclo-hexyl-ethan-1-aminium 2-chloro-4-nitro-benzoate, CHN·CHClNO, (V), 2-(cyclo-hex-1-en-1-yl)ethan-1-aminium 4-bromo-benzoate, CHN·CHBrO, (VI), and ()-1-cyclo-hexyl-ethan-1-aminium 4-bromo-benzoate, CHN·CHBrO, (VII). Salts (II) to (VII) feature three N-H⋯O hydrogen bonds, which form one-dimensional hydrogen-bonded ladders. Salts (II), (III), (IV), (V) and (VII) have a type ladder system despite the presence of halogen bonding and other inter-molecular inter-actions, whereas (VI) has a type ladder system.

The economics of restoration: looking back and leaping forward.

Since the publication of the Millennium Ecosystem Assessment in 2005 there has been a surge of interest in ecological restoration (ER) to recover biodiversity, re-establish ecosystem functioning and connectivity, and reactivate the delivery of ecosystem services. In policy spheres, there have also been repeated calls for expansion of restoration efforts. In many countries, new legislation now requires some form of restoration and/or a form of offset investment.

The financial and economic feasibility of rural household biodigesters for poor communities in South Africa.

Given the persistence of systemic poverty in, most notably, the rural parts of South Africa, the question is whether the use of biodigesters as a source of energy offers potential solutions to some of the difficulties and development needs faced by people in these areas. At the core, this translates into whether this technology would be financially and economically feasible for installation and use by rural households. Here we conduct both a financial and an economic cost-benefit analysis in one such community based on survey data from 120 households.

Benefits of investing in ecosystem restoration.

Measures aimed at conservation or restoration of ecosystems are often seen as net-cost projects by governments and businesses because they are based on incomplete and often faulty cost-benefit analyses. After screening over 200 studies, we examined the costs (94 studies) and benefits (225 studies) of ecosystem restoration projects that had sufficient reliable data in 9 different biomes ranging from coral reefs to tropical forests. Costs included capital investment and maintenance of the restoration project, and benefits were based on the monetary value of the total bundle of ecosystem services provided by the restored ecosystem.

System dynamic modelling to assess economic viability and risk trade-offs for ecological restoration in South Africa.

Can markets assist by providing support for ecological restoration, and if so, under what conditions? The first step in addressing this question is to develop a consistent methodology for economic evaluation of ecological restoration projects. A risk analysis process was followed in which a system dynamics model was constructed for eight diverse case study sites where ecological restoration is currently being pursued. Restoration costs vary across each of these sites, as do the benefits associated with restored ecosystem functioning.

The road to sustainability must bridge three great divides.

The world's large and rapidly growing human population is exhausting Earth's natural capital at ever-faster rates, and yet appears mostly oblivious to the fact that these resources are limited. This is dangerous for our well-being and perhaps for our survival, as documented by numerous studies over many years. Why are we not moving instead toward sustainable levels of use? We argue here that this disconnection between our knowledge and our actions is largely caused by three "great divides": an ideological divide between economists and ecologists; an economic development divide between the rich and the poor; and an information divide, which obstructs communications between scientists, public opinion, and policy makers.

Differences in hypertension between blacks and whites: an overview.

Hypertension is more prevalent and severe in urban black populations compared to whites, and is associated with a greater degree of target-organ damage for any given blood pressure level. In general, compared to whites, blacks respond well to diuretics and calcium channel blockers and less well to beta-blockers and ACE inhibitors. The exact mechanisms that contribute to differences in blood pressure between blacks and whites are still not fully understood, given the multi-factorial aetiology of essential hypertension.

An inclusion technique for marking dentures.

The importance of placing identification markers in dentures is well documented and this paper describes a simple and inexpensive technique for doing it. Twenty marked upper acrylic simulated dentures and 20 controls (unlabelled) were constructed in a standardized mould. Clear laminated labels were produced in a P-touch 300 electronic lettering system and contained both the patient's identification number and suffix ZA (international code for South Africa).

The resistance to deformation forces of endodontic posts manufactured from six different materials.

Twenty posts of 1.25 mm diameter and 10 of 1.0 mm diameter were cast in 4 different metals, namely, Argenco 4, Argenco 9, Wiron 99 and Rexillium V (5 each).

Replacing amalgam fillings with composite inlays--a case report.

The latest revival of the old amalgam controversy is causing dentists to be inundated with requests from patients to replace their amalgam fillings with more "acceptable" filling materials. A patient with chronic lymphocytic leukaemia has been monitored since 1981. All his amalgam fillings were replaced by baked composite inlays.

High fruit consumption and the periodontal status of farm workers.

The results of a study on the periodontal health of orchard and vineyard workers on apple, grape, citrus and mixed-variety fruit farms are presented. Workers on grain farms were used as controls. The only significant differences in the diets of the different groups were the very large amounts of fresh fruits eaten by the fruit-farm workers.

The effect of a high consumption of apples or grapes on dental caries and periodontal disease in humans.

The intent of this study was to determine the effect of a high consumption of either apples or grapes on the caries experience (DMFT), and periodontal health. Farm workers employed by apple-producing, grape-producing and grain (control) producing farms in low fluoride areas (F less than 0.10 ppm) were investigated.

Injuries sustained in rugby by wearers and non-wearers of mouthguards.

Previous studies have shown a higher prevalence of head and neck injuries in non-wearers when compared with wearers of mouthguards. The purpose of the present study was to compare the pattern of injuries to those of past studies and also to investigate whether the injuries sustained differed significantly between wearers and non-wearers. A sample of 321 university students participating on 555 player occasions was studied in a cross-sectional survey.

[Radionuclide exercise gated studies in female patients with positive exercise electrocardiogram].

Radionuclide left ventricular ejection fraction (LVEF) has been determined in a group of 14 female patients at rest and during graded supine bicycle exercise. One group consisted of 9 patients complaining of chest pain and demonstrating positive exercise electrocardiography (EECG), but with normal contrast angiographic results. The second group of 5 patients had a normal response to EECG and was used as a control group.