153 research outputs found
Innovation in overcoming road rehabilitation challenges faced in an urban environment: An in-depth case study
Paper presented at the 32nd Annual Southern African Transport Conference 8-11 July 2013 "Transport and Sustainable Infrastructure", CSIR International Convention Centre, Pretoria, South Africa.The design and implementation of a pavement rehabilitation project in a Central Business
District (CBD) of a city poses numerous challenges. These challenges include the high design traffic, depth of pavement rehabilitation, presence of many services, traffic accommodation, pedestrian accommodation, construction period, construction materials,
final level of construction, environmental and social impact and sustainability.
The paper presents a case study of an innovative pavement design and construction process for the rehabilitation of Harvey Road and Hanger Street in Bloemfontein, South Africa. The paper addresses the practical rehabilitation option, which met the challenges faced on the project, as well as the construction materials mix design details, construction
methods, time frames during construction as well as a cost comparison between conventional deep rehabilitation pavements and the innovative rehabilitation pavement.
The design incorporates a bitumen emulsion stabilised crushed stone base, which includes reclaimed asphalt, paved with a paver on top of a mechanical stabilising grid.This paper was transferred from the original CD ROM created for this conference. The material was published using Adobe Acrobat 10.1.0 Technology.
The original CD ROM was produced by Document Transformation Technologies Postal Address: PO Box 560 Irene 0062 South Africa. Tel.: +27 12 667 2074 Fax: +27 12 667 2766 E-mail: nigel@doctech URL: http://www.doctech.co.zamv201
Determinants of advice seeking within defined contribution retirement savings schemes
We report results from a study of superannuation member advice-seeking within their plan, explaining observed patterns by member age, gender, issue salience, and size-of-bet effect. Inquiry mode, frequency and volume of contact with the advice-provider, and sensitivity of members to legislative change and macroeconomic events are considered. Results show that gender (female more likely than male), age (older rather than younger), balance (larger rather than smaller) and experience (longer rather than shorter), are the strongest advice-seeking predictors, consistent over time. Findings suggest member engagement around retirement planning may be more effective when considering the factors affecting advice-seeking behaviour in general
Highly Luminescent Salts Containing Well-Shielded Lanthanide-Centered Complex Anions and Bulky Imidazolium Countercations
In this paper, we report on the syntheses, structures, and characterization of four molten salts containing imidazolium cations and europium(III)- or terbium(III)-centered complex anions. In the complex anions, the lanthanide centers are wrapped by four pseudodiketonate anionic ligands, which prevent them from contacting with high-frequency oscillators and allow them to show intense characteristic europium(III) or terbium(III) emission, small line widths, high color purity, high quantum yields (30−49%), and long decay times (\u3e2 ms)
Green Pathways for the Enzymatic Synthesis of Furan-Based Polyesters and Polyamides
The attention towards the utilization of sustainable feedstocks for polymer synthesis has grown exponentially in recent years. One of the spotlighted monomers derived from renewable resources is 2,5-furandicarboxylic acid (FDCA), one of the most promising bio-based monomers, due to its resemblance to petroleum-based terephthalic acid. Very interesting synthetic routes using this monomer have been reported in the last two decades. Combining the use of bio-based monomers and non-toxic chemicals via enzymatic polymerizations can lead to a robust and favorable approach towards a greener technology of bio-based polymer production. In this chapter, a brief introduction to FDCA-based monomers and enzymatic polymerizations is given, particularly focusing on furan-based polymers and their polymerization. In addition, an outline of the recent developments in the field of enzymatic polymerizations is discussed. </p
Deep Eutectic Solvents (DESs) and their applications [forthcoming]
Deep Eutectic Solvents (DESs) and Their Application
In Vivo Magnetic Resonance Imaging and Microwave Thermotherapy of Cancer Using Novel Chitosan Microcapsules
Risk factors for Coronavirus Disease 2019 (COVID-19) death in a population cohort study from the Western Cape Province, South Africa
BACKGROUND. Risk factors for coronavirus disease 2019 (COVID-19) death in sub-Saharan Africa and the effects of human immunodeficiency
virus (HIV) and tuberculosis on COVID-19 outcomes are unknown.
METHODS. We conducted a population cohort study using linked data from adults attending public-sector health facilities in the
Western Cape, South Africa. We used Cox proportional hazards models, adjusted for age, sex, location, and comorbidities, to examine
the associations between HIV, tuberculosis, and COVID-19 death from 1 March to 9 June 2020 among (1) public-sector “active
patients” (≥1 visit in the 3 years before March 2020); (2) laboratory-diagnosed COVID-19 cases; and (3) hospitalized COVID-19
cases. We calculated the standardized mortality ratio (SMR) for COVID-19, comparing adults living with and without HIV using
modeled population estimates.
RESULTS. Among 3 460 932 patients (16% living with HIV), 22 308 were diagnosed with COVID-19, of whom 625 died. COVID-
19 death was associated with male sex, increasing age, diabetes, hypertension, and chronic kidney disease. HIV was associated with
COVID-19 mortality (adjusted hazard ratio [aHR], 2.14; 95% confidence interval [CI], 1.70–2.70), with similar risks across strata of
viral loads and immunosuppression. Current and previous diagnoses of tuberculosis were associated with COVID-19 death (aHR,
2.70 [95% CI, 1.81–4.04] and 1.51 [95% CI, 1.18–1.93], respectively). The SMR for COVID-19 death associated with HIV was 2.39
(95% CI, 1.96–2.86); population attributable fraction 8.5% (95% CI, 6.1–11.1).
CONCLUSIONS. While our findings may overestimate HIV- and tuberculosis-associated COVID-19 mortality risks due to residual
confounding, both living with HIV and having current tuberculosis were independently associated with increased COVID-19 mortality.
The associations between age, sex, and other comorbidities and COVID-19 mortality were similar to those in other settings.The Western Cape Provincial Health Data Centre from the Western Cape Department of Health, the US National Institutes for Health (grant numbers R01 HD0804, the Bill and Melinda Gates Foundation, the United States Agency for International Development and the Wellcome Trust.https://academic.oup.com/cid/am2023Veterinary Tropical Disease
Highly Luminescent Salts Containing Well-Shielded Lanthanide-Centered Complex Anions and Bulky Imidazolium Countercations
- …