Purpose
This paper aims to present a new master’s programme for promoting energy access and energy efficiency in Southern Africa.
Design/methodology/approach
A transdisciplinary approach called ...“participatory integrated assessment of energy systems” (PARTICIPIA) was used for the development of the curriculum. This approach is based on the two emerging fields of “multi-scale integrated assessment” and “science for governance”, which bring innovative concepts and methods.
Findings
The application of the PARTICIPIA methodology to three case studies reveals that the proposed transdisciplinary approach could support energy and development policies in the region. The implementation of the PARTICIPIA curriculum in three higher education institutions reveals its ability to respond to the needs of specific contexts and its connection with existing higher education programmes.
Practical implications
Considering energy issues from a transdisciplinary approach in higher education is absolutely critical because such a holistic view cannot be achieved through engineering curricula. Deliberate and greater efforts should be made to integrate methods from “multi-scale integrated assessment” and “science for governance” in higher education curricula to train a new breed of modern-day energy planners in charge of coming up with solutions that are shared by all relevant stakeholders.
Originality/value
This paper presents an innovative higher education curriculum in terms of the attention given to energy access and energy efficiency that affect the southern Africa region and the nature of the methodology adopted to face these issues.
The choice of an appropriate solvent system for Countercurrent Chromatography (CCC) is a critical step in the purification of natural products. Targeted towards their high sample diversity, ...G.U.E.S.S. is a practical approach for the prediction of CCC distribution constants, K values, by standard thin layer chromatography (TLC). G.U.E.S.S. allows a major reduction in workload by direct use of routine TLC information. The separation capability of CCC focuses on an optimal "window of opportunity" that can be described as the "sweet spot" of CCC separation. The sweet spot of optimal CCC performance may be described as an area where compound K values are between 0.4 and 2.5. Two useful CCC solvent systems: hexane/ethyl acetate/methanol/water and chloroform/methanol/water are organized and recommended as the HEMWat and ChMWat methods of solvent system selection. The relationship of (i) P values, measured by the ratio of UV-vis absorption, (ii) TLC R
f
values and (iii) CCC retention volumes for over 20 diverse commercially available natural products are described. The HEMWat method characterizes a versatile solvent selection technique. TLC R
f
values will often give practical predictions, even with simple single-phase mixtures. Additional information can be acquired from equivalent solvent systems and by calibration with the G.U.E.S.S. standard compounds. The latter will also aid in the important selection of which phase will function as the mobile phase. The choice of normal vs. reverse phase will depend on the polarity of compounds that are desired to be gathered into the sweet spot. In addition, G.U.E.S.S. has been shown to be readily applicable to natural product purification necessary for drug discovery, bioassay guided fractionation, and metabolome analysis.
Tumor necrosis factor-α (TNF-α) is a potent cytokine with anticancer efficacy that can significantly enhance hyperthermic
injury. However, TNF-α is systemically toxic, thereby creating a need for its ...selective tumor delivery. We used a newly developed
nanoparticle delivery system consisting of 33-nm polyethylene glycol–coated colloidal gold nanoparticles (PT-cAu-TNF-α) with
incorporated TNF-α payload (several hundred TNF-α molecules per nanoparticle) to maximize tumor damage and minimize systemic
exposure to TNF-α. SCK mammary carcinomas grown in A/J mice were treated with 125 or 250 μg/kg PT-cAu-TNF-α alone or followed
by local heating at 42.5°C using a water bath for 60 minutes, 4 hours after nanoparticle injection. Increases in tumor growth
delay were observed for both PT-cAu-TNF-α alone and heat alone, although the most dramatic effect was found in the combination
treatment. Tumor blood flow was significantly suppressed 4 hours after an i.v. injection of free TNF-α or PT-cAu-TNF-α. Tumor
perfusion, imaged by contrast enhanced ultrasonography, on days 1 and 5 after treatment revealed perfusion defects after the
injection of PT-cAu-TNF-α alone and, in many regions, complete flow inhibition in tumors treated with combination treatment.
The combination treatment of SCK tumors in vivo reduced the in vivo/in vitro tumor cell survival to 0.05% immediately following heating and to 0.005% at 18 hours after heating, suggesting vascular damage–mediated
tumor cell killing. Thermally induced tumor growth delay was enhanced by pretreatment with TNF-α-coated gold nanoparticles
when given i.v. at the proper dosage and timing. Mol Cancer Ther 2006;5(4):1014–20
Numerous studies of treatment for Hodgkin's disease have demonstrated large increases in the incidence of leukemia in the early years following chemotherapy, although the duration of effect and the ...specific agents involved are not well understood. Also, some, but not all, studies have indicated that the incidence of certain solid tumors increases following treatment for Hodgkin's disease.
We studied the association between treatment for Hodgkin's disease and the incidence of second cancers.
We conducted a study within a cohort that included 10,472 patients from 14 cancer centers in the United States and Canada who were first diagnosed as having Hodgkin's disease at some point from 1940 through 1987. Discounting the 1st year after diagnosis, the average length of follow-up was 7.1 years per subject.
We observed 122 leukemias and 438 solid tumors. The relative risk (RR) of leukemia following chemotherapy, compared with no chemotherapy, was 14 (95% confidence interval CI = 5.6-35). Increased risks of leukemia were observed after treatment with chlorambucil (RR = 2.0; 95% CI = 1.1-3.6), procarbazine (RR = 4.9; 95% CI = 2.6-9.1), vinblastine (RR = 1.7; 95% CI = 1.1-2.8), and a group of rarely used drugs that included methotrexate, vindesine, etoposide, and 22 others (RR = 3.8; 95% CI = 1.9-7.4). RRs were also estimated for various combinations of drugs, including MOPP (mechlorethamine, vincristine, procarbazine, and prednisone) (RR = 5.9; 95% CI = 2.9-12) and ABVD (doxorubicin, bleomycin, vinblastine, and dacarbazine) (RR = 1.5; 95% CI = 0.7-3.4). The RR of leukemia associated with splenectomy was 1.6 (95% CI = 1.0-2.5). The RR of solid tumors following chemotherapy was 1.4 (95% CI = 1.1-1.8). For the group of rarely used drugs, the RR of solid tumors was 3.1 (95% CI = 1.7-5.8). Chemotherapy was associated with an increased risk of cancers of the bones, joints, articular cartilage, and soft tissues (RR = 6.0; 95% CI = 1.7-20), and cancers of the female genital system (RR = 1.8; 95% CI = 1.1-3.2). In patients followed for 10 or more years after radiotherapy, increased risks were found for cancers of the respiratory system and intrathoracic organs (RR = 2.7; 95% CI = 1.1-6.8) and for cancers of the female genital system (RR = 2.4; 95% CI = 1.1-5.4).
Procarbazine, chlorambucil, and vinblastine are associated with increased leukemia risk. Combination drug regimens have leukemogenic effects estimated as the product of RRs for individual drugs. Chemotherapy and radiotherapy increase the risk of selected solid tumors, and the effect of chemotherapy on solid tumor risk is weaker than the leukemogenic effect.
Without doubt, the benefits of treatment of Hodgkin's disease outweigh the risk of a subsequent malignancy, but data on the carcinogenic effects of radiation and drugs beyond 10 years after treatment continue to be sparse, and future analyses should be directed at long-term survivors.
Carbon isotope fractionation produced by anaerobic biodegradation of toluene was evaluated in laboratory experiments under both methanogenic and sulfate-reducing conditions. A small (∼2‰) but highly ...reproducible 13C-enrichment in the residual toluene at advanced stages of microbial transformation was observed in both cultures. The maximum isotopic enrichment observed in the residual toluene was +2.0‰ and +2.4‰ for the methanogenic and sulfate-reducing cultures, respectively, corresponding to isotopic enrichment factors (ε) of −0.5 and −0.8. Because the accuracy and reproducibility associated with gas chromatograph−combustion−isotope ratio mass spectrometry (GC/C/IRMS) is ±0.5‰, delineating which of these two terminal electron-accepting processes (TEAP) is responsible for the biodegradation of toluene at field sites will not be possible. However, the potential does exist to use compound-specific isotope analysis (CSIA), in conjunction with other methodologies, as a means of validating advanced stages of intrinsic bioremediation in anaerobic systems. Caution is urged that relating this small (∼2‰) fractionation to biodegradation at complex field sites will prove a challenge.
•We review Prof. Sherwood Lollar’s contributions to Compound Specific Isotope Analysis.•We address contributions to contaminant hydrogeology and environmental chemistry.•We discuss contributions to ...fundamental science and to the remediation industry.
Here, we review the contributions of Professor Barbara Sherwood Lollar to Compound Specific Isotope Analysis (CSIA) in contaminant hydrogeology and environmental chemistry. We first discuss the seminal work by Professor Sherwood Lollar’s lab on establishing CSIA as a quantitative tool for contaminant (bio)transformation at contaminated groundwater sites. We describe the critical research by her lab in the development and validation of sample collection techniques, single- and multi-element CSIA, and isotope data evaluation for reliable interpretations. We highlight the contributions of Professor Sherwood Lollar’s lab towards the development of best practices for the successful application of CSIA by industry to demonstrate the occurrence of (bio)transformation, identify (bio)transformation mechanisms, quantify the extent and rate of degradation and differentiate among potential contaminant sources. We then explore Professor Sherwood Lollar’s applications of CSIA to hydrogeology of the deep subsurface and the fast widening of the field to new environments (e.g., sediments), contaminants (e.g., chlorofluorocarbons, pesticides), and systems (e.g., plant, enzymes).
•The dissolution kinetics of roasted lizardite at different T and pH were studied.•An initial rapid liberation of Mg2+ followed by a very slow extraction was observed.•Increasing temperature caused ...an increase in the rate of Mg extraction initially.•The extent of extraction of Mg2+ decreased due to precipitation of silica.•Silica re-precipitation at high temperature and S/L was demonstrated.
The dissolution of magnesium silicate minerals such as serpentine in aqueous solutions saturated or near saturated with carbon dioxide (CO2) enables its subsequent reaction to form magnesium carbonate, a process called aqueous mineral carbonation. The dissolution rate of magnesium ions (Mg2+) from thermally activated serpentine and the factors influencing the rate and extent of dissolution have been studied in our research group. The current contribution focuses on the effect of temperature and pH on the dissolution of heat activated lizardite (a polymorph of serpentine). The extent of dissolution of thermally activated lizardite was measured experimentally as a function of temperature (25 °C ≤ T ≤ 75 °C) and pH (1.2 ≤ pH ≤ 9.8). It was found that at higher temperatures the level of Mg extraction is greater during the initial stage of dissolution but is then hindered by the re-precipitation of amorphous silica. Thermodynamic modelling was used to assess the susceptibility of solid phase formation and confirmed the likelihood of re-precipitation of amorphous silica from the solutions. For the first time, in this work, the crackling core model (CCM) was used to model experimental data at different pH values.
Immune responses require the orchestrated migration of T cells throughout the body. Conventional CD4+ and CD8+ αβ T cells undergo clonal expansion in the secondary lymphoid tissues, during which they ...are programmed to migrate into specific non-lymphoid tissues and other lymphoid effector sites such as B cell follicles. By contrast, T cell populations expressing receptors with limited diversity (i.e. γδ T cells and NK T cells) appear to be preprogrammed to localize in non-lymphoid tissues where they monitor tissue integrity or serve regulatory functions. By promoting chemotaxis and integrin activation, chemokines and their receptors (in conjunction with surface adhesion molecules) control these T cell homing events. Thus, expression of chemokine receptors defines T cells with tropism for particular tissues and/or microenvironments, and identifies T cell subsets with distinct functional properties.
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