The ridgelet transform with non-linear threshold for seismic noise attenuation in marine carbonates

Wavelet transforms have been successfully used in seismic data processing with their ability for local time - frequency analysis. However, identification of directionality is limited because wavelet transform coefficients reveal only three spatial orientations. Whereas the ridgelet transform has a superior capability for direction detection and the ability to process signals with linearly changing characteristics. In this paper, we present the issue of low signal-to-noise ratio （SNR） seismic data processing based on the ridgelet transform. Actual seismic data with low SNR from south China has been processed using ridgelet transforms to improve the SNR and the continuity of seismic events. The results show that the ridgelet transform is better than the wavelet transform for these tasks.

The Expression and Functional Analysis of the Gene At2G34450 in High Mobility Group B Proteins from Arabidopsis thaliana

[Objective]To better understand the functions of High Mobility Group B （HMGB） proteins in the transcriptional regulation of plant stress responses.[Method]We cloned the At2G33450 gene encoding At2G34450 protein in Arabidopsis thaliana.Binary vectors carrying the above gene were transformed into Arabidopsis to detect the influences of environmental stimuli to transgenic Arabidopsis.[Result] Under salt or drought stress the transgenic Arabidopsis plants over-expressed At2G33450 displayed retarded germination and subsequent growth compared with wild-type plants.[Conclusion]Our results provide a novel basis for understanding the biological functions of HMGB protein family members that differently affect germination and seedling growth of Arabidopsis plants under various stress conditions.

AN EXPERT SYSTEM ON ASSESSING ROCKBURST RISKS FOR SOUTH AFRICAN DEEP GOLD MINES

Expert systems are methods that can cope with rock engineer’s expertise effectively.An expert system on assessing rockburst risks for South African deep gold mines is described.Expertise was represented by rules, frames and mathematical models integratively. About 950 rules was built in the knowledge base, which can be learned by the suggested learning algorithm. A new uncertain reasoning algorithm was proposed. According to the features such as depth below surface, energy release rate (ERR), excess shear stress (ESS), geological structure, face angle with structure, distance from structure, extent of mining, mining type, width of bracket pillar, stope width, local support, regional support and gully support, rockburst risk is assessed either "Low", "Moderate", "High" or "Severe". A computer program system was developed by Turbo Prolog. The results of testing cases show its applicability of the system.

Characterization of coal using electron spin resonance： implications for the formation of inertinite macerals in the Witbank Coalfield, South Africa

Coal contains a significant concentration of free radicals as a result of the coalification process. One of the experimental methods sensitive to the presence of radicals is electron spin resonance （ESR）, and differences in ESR spectra for different macerals may provide insight into coal-forming processes. In this study, ESR data along with the H/C atomic ratio （to infer the aromatic fraction） are used to characterize coal samples with the aim of assessing a fire-origin for dominant inertinite macerals. A medium rank C bituminous Witbank No. 4 Seam Upper coal （the parent） was density- fractionated to create vitrinite-rich and inertinite-rich samples. The parent sample consists of 42 vol% vitrinite and 49 vol% inertinite. The density-fractionated samples comprise of 81 vol% total vitrinite （dominated by collotelinite and collodetrinite）, and 63 vol% total inertinite （dominated by fusinite, semifusinite, and inertodetrinite）. The H/C ratio is 0.74 for the inertinite-rich sample, and 0.85 for the vitrinite-rich counterpart, suggesting the former sample is more aromatic. The ESR spectra obtained for the three samples were found to fit best using a Lorentzian distribution. The fit is noticeably better for the aromatic inertinite-rich sample, for which the spectrum is symmetric. This is attributed to pronounced electron mobility and exchange interactions. The higher radical content of the inertinite-rich and parent samples is attributed to the presence of specific inertinite macerals, namely： fusinite, semifusinite, and inertodetrinite. And, owing to the greater radical content of the inertinite-rich sample, the dominant inertinite macerals are interpreted to have formed through charring of plant matter.

Isolation of an Arabidopsis Gene Encoding Ins (1,3,4) P_3 5/6-Kinase-like Protein and Involved in Plant Response to Abiotic Stresses

By mRNA differential display from control versus NaCl_shocked Arabidopsis seedlings, we screened an Arabidopsis 3′ partial cDNA, which represents a gene encoding inositol 1,3,4_trisphosphate (Ins(1,3,4)P 3) 5/6_kinase_like protein. Northern blotting analysis showed that the gene, named as AtITL1, is strongly induced by NaCl and low temperature, but not induced by drought and abscisic acid (ABA). Analysis of 5′ region of the AtITL1 found that there are dehydration_responsive element/C_repeat (DRE/CRT) cis _acting elements, but no elements related to G_box and ABRE (ABA_responsive element) in its 5′ region, which is consistent with the expression patterns of the AtITL1 independent of ABA. These results suggest that the AtITL1 may be involved in the osmotic stress response pathway independent of ABA.

The importance of non-carbonate mineral weathering as a soil formation mechanism within a karst weathering profile in the SPECTRA Critical Zone Observatory, Guizhou Province,China

Soil degradation, including rocky desertification,of the karst regions in China is severe. Karst landscapes are especially sensitive to soil degradation as carbonate rocks are nutrient-poor and easily eroded. Understanding the balance between soil formation and soil erosion is critical for long-term soil sustainability, yet little is known about the initial soil forming processes on karst terrain. Herein we examine the initial weathering processes of several types of carbonate bedrock containing varying amounts of non-carbonate minerals in the SPECTRA Critical Zone Observatory, Guizhou Province, Southwest China. We compared the weathering mechanisms of the bedrock to the mass transfer of mineral nutrients in a soil profile developed on these rocks and found that soil formation and nutrient contents are strongly dependent upon the weathering of interbedded layers of more silicate-rich bedrock(marls). Atmospheric inputs from dust were also detected.

CHARACTERISTICS OF FREQUENCY SPECTRUM VARIATION OF INTRASEASONAL OSCILLATION OF CONVECTION DURING SOUTH CHINA SEA SUMMER MONSOON

Datasets of equivalent temperature of black body (TBB) and sea surface temperature (SST)ranging from 1980 to 1997 are used to diagnose and analyze the characteristics of frequency spectrum andstrength of intraseasonal variation of convection. The relationship between the strength of intraseasonaloscillation of convection, strength of convection itself and SST in the South China Sea (SCS) is studied. It isshown that, there are distinguishable annual, interannual and interdecadal variations in both strength andfrequency spectrum of intraseasonal variation of convection in SCS. There are connections between strength ofconvection, strength of ISO1 in the summer half (s.h.) year and SST in ensuing winter half (w.h.) year in SCS.The strong (weak) convection and strong (weak) ISO1 are associated with negative (positive) bias of SST inensuing w.h. year in SCS.

Parametric study of electrostatic separation of South African fine coal

The fact that water requirements are a major problem for present and future developments in material beneficiation, and the construction of a new power plant in South Africa, forms the basis for the utilization of a Rotary Triboelectrostatic Separator (RTS) for beneficiation of South African pulverized coal. The cleaning potential of Majuba and Koorfontein coal was first evaluated using kinetic froth flotation tests on the -177 μm coal fraction. The RTS tests were conducted under varied process parameters. Parameters such as applied separating voltage, air injection velocity, particle feed rate and splitter position were investigated. Two stage separation results show that the RTS reduced Majuba coal initially containing about 30% ash to a clean product of 14.30%, or 19.46%, ash at a combustible recovery of 15.10%, or 53.02%, respectively. Similar separation performance was also achieved with the Koorfontein coal. The mineral and organic compositions in the feed, after single stage and after the second stage separations were characterized using X-ray diffraction analysis. The results show a better separation for the second stage coal products.

Cleaning of South African coal using a compound dry cleaning apparatus

The compound dry cleaning principle is briefly described.A beneficiation test on South African coal was conducted using a model compound dry cleaning apparatus.Excellent results were obtained and the optimum operating parameters were determined.They are：an amplitude of 3.0 mm,a motor frequency of 47.5 Hz,an air volume of 50%,a transverse angle of 7°,and a longitudinal angle of-2°.These conditions yield a clean coal containing 11%ash and a coal production of 75%.The organic efficiency,η,is 95.86%.These results show that the South African coal can be separated effectively by compound dry cleaning,which will popularize the compound dry cleaning method.

Influence of Flow Regime on the Vegetation Zonation along Mountain Streams in the Western Cape, South Africa

Zonation patterns of riparian vegetation have been sampled and described in mountain streams in two catchments in the Hottentots-Holland Mountains, Western Cape, South Africa. Six main vegetation types that differ in structure and species composition, are dominant along these river banks: Aquatic vegetation, Wetbanks, Palmiet, Scrub, Forest and Shrubland(Fynbos). The study aims to correlate the vegetation patterns to flooding patterns, in particular the inundation frequency and stream power. A problem arises: because these catchments are ungauged, like most mountain catchments, with the only weirs at the downstream end of the catchment. Discharge data at the weirs are extrapolated to the sites upstream by multiplication with a factor based on the size of the subcatchment that drains through a sample site. In this way, recurrence intervals for floods in mountain streams are derived. Discharges at sites are also calculated using bed roughness(Manning's n) and slope in straight sections with uniform flow conditions. Stream power is derived from the discharges calculated in this manner. The combination of stream power and recurrence intervals explains the occurrence of most vegetation types occurring on the banks, except for one type: Afromontane Forest. This type is probably more dependent on other factors, such as protection from fire and the depth of the groundwater table.

Acacia mearnsii management in a South African National Parks：SWOT analysis using hot topics in biological invasion as a guide

The assessment of the policy framework governing Invasive Alien Species(IAS) control is of critical importance in conservation. The undertaking of a SWOT analysis of such a framework is necessary because it enhances the efficacy of IAS control. The aim of this study is to carry out a SWOT analysis of the policy framework guiding the control of the spreading of Acacia mearnsii and other IAS in the Golden Gate Highlands National Park in South Africa,as well as the implementation of restorative measures in the park and adjacent communities in line with the recommendations of the Convention on Biodiversity. A comparative analysis of this framework and the hierarchical framework that was developed during the European Union Conference on Freshwater Invasives- Networking for Strategy in 2013 is undertaken. The results indicate the need to strengthen parkcommunity relations,upgrade existing legislation,and boost the technical capacity of South African national parks to identify,detect,monitor and predict IAS invasions,both within the parks and their surroundings. This knowledge is important for developing future policies on IAS control in South Africa.

Inference of Global HIV-1 Sequence Patterns and Preliminary FeatureAnalysis

The epidemiology of HIV-1 varies in different areas of the world, and it is possible that this complexity may leave unique footprints in the viral genome. Thus, we attempted to find significant patterns in global HIV-1 genome sequences. By applying the rule inference algorithm RIPPER (Repeated Incremental Pruning to Produce Error Reduction) to multiple sequence alignments of Env sequences from four classes of compiled datasets, we generated four sets of signature patterns. We found that these patterns were able to distinguish southeastern Asian from non- southeastern Asian sequences with 97.5% accuracy, Chinese from non-Chinese sequences with 98.3% accuracy, African from non-African sequences with 88.4% accuracy, and southern African from non-southern African sequences with 91.2% accuracy. These patterns showed different associations with subtypes and with amino acid positions. In addition, some signature patterns were characteristic of the geographic area from which the sample was taken. Amino acid features corresponding to the phylogenetic clustering of HIV-1 sequences were consistent with some of the deduced patterns. Using a combination of patterns inferred from subtypes B, C, and all subtypes chimeric with CRF01_AE worldwide, we found that signature patterns of subtype C were extremely common in some sampled countries (for example, Zambia in southern Africa), which may hint at the origin of this HIV-1 subtype and the need to pay special attention to this area of Africa. Signature patterns of subtype B sequences were associated with different countries. Even more, there are distinct patterns at single position 21 with glycine, leucine and isoleucine corresponding to subtype C, B and all possible recombination forms chimeric with CRF01_AE, which also indicate distinct geographic features. Our method widens the scope of inference of signature from geographic, genetic, and genomic viewpoints. These findings may provide a valuable reference for epidemiological research or vaccine design.

Community Based Natural Resource Management, Tourism and Poverty Alleviation in Southern Africa： What Works and What Doesn＇t Work

Community based natural resource management （CBNRM） is perhaps the most important tool for driving community and rural development in southern Africa. The paper therefore analyses the CBNRM framework as a strategy for implementing sustainable tourism and poverty alleviation initiatives in Botswana, Namibia, and Zambia. The article specifically underscores the importance of local-level participatory management and utilisation of natural resources in the region. Paying special attention to the previous researches that have been conducted in Botswana, Namibia, and Zambia, the methodological approach employed in the paper centres on critical discourse analysis and review of literatures to highlight the interface existing between CBNRM and rural （tourism） development. The analytical framework of the paper is thus rooted in the Common Property Resource （CPR） theory Overall, the authors argue that tourism, poverty alleviation, rural development, and sustainable natural resource use are linked and interrelated in the process of enhancing community well-being. Findings indicate that CBNRM initiatives have had a significant and positive impact in achieving sustainable tourism, rural development, poverty alleviation, and natural resource management. Specifically, findings show that the CBNRM has contributed to the reduction in wildlife poaching. While other pertinent issues remain, national governments in the three southern African economies need to fully appropriate the benefits that CBNRM offers and improve on them for better implementation of developmental programs.

An Assessment of the Level of Knowledge of HIV-Infected Patients about Highly Active Antireteroviral Therapy and Waiting Times and Their Influence on Antiretroviral Therapy Adherence at a Primary Healthcare Centre of South Africa

Objectives： The study assessed if the level of knowledge of HIV-infected about HAART and waiting-times in the PHC （primary healthcare） clinic have an influence on antiretroviral adherence. Methods： A descriptive-cross-sectional study was conducted in South Africa. Data collected uses a standardized-questionnaire and face-to-face-exit interviews. Pill-count technique was performed and a value of≥ 95% acceptable. Data were analysed using SPSS. Univariate-factors associated with poor-adherence to knowledge about HAART and waiting times were assessed using ANOVA and p ≤ 0.05 considered statistically significant. Key findings： Of 86 enrolled, 63（73.3%） were females and 23（26.7%） males, with mean-age （± SD） of 35.6（±9.6） years and on HAART for 35.5（± 31.8） months ranging from 1-137. Of these, 27（31.40%） and 25（29.07%） were on WHO stages 2 and 3 respectively. Adherence-rates computed from 32 patients, 23（71.9%） revealed poor adherence-rates. The level of knowledge about HAART in terms of names of tablets, correct-dose, frequency, adverse-effects had no influence on ARV-adherence （p _〉 0.05）. Of 23 non-compliant, 10 （40%） gave the reason of drugs-unavailability, 7（30%） adverse-effects, 5（20%） drugs＇ complexity, and 1（10%） too busy to take them. Waiting areas associated with poor ARV-adherence were reception （p = 0.028）, doctors （p = 0.027）, while nurse＇s station （p = 0.29） and pharmacy （p = 0.43） revealed acceptable ARV-adherence.

Influences of Seed Source, Pre-chilling, Light and Temperature on the Germination of South African Pelargonium sidoides

Pelargonium sidoides DC is used in herbal medicine for the treatment of various infections. The roots are being indiscriminately harvested for local and export trade and the collection rate is becoming unsustainable. Seed germination dynamics of this species was studied with the aim to reveal factors that influence its survival in the wild in order to adopt the appropriate germination conditions for use in ex-situ propagation and conservation program. Germination was affected by age of seeds, temperature and pre-chilling conditions. Temperature higher than 25 oC reduced germination by 60%. When seeds of P. sidoides were subjected to pre-chilling treatment for seven days, there was a significant drop in final germination by 29% compared to the other treatments. Although, final germination was not affected by different light treatments, continuous light significantly promoted germination velocity Seeds harvested from the plants grown in the green house performed better in germination than those collected from the field. The ecological implications of these observations on the propagation and conservation ofP. sidoides are discussed.

The development and evaluation of a nurse anaesthesia model for practice in South Africa

Objective This article aimed to present a developed model for nurse anaesthesia practice in South Africa and then to evaluate the model by national and international anaesthetist experts.Methods For the model development,a theory-generative research design was used as guided by Chinn&Kramer.The study included four steps to develop and evaluate the model:step one,concept analysis;step two,placing the concepts into relationships;step three,description and critical reflection of the model;step four,evaluation of the model.For evaluation of the model,data were collected using individual,in-depth interviews.Four South African medical specialist anaesthesiologists and four international nurse anaesthetists were interviewed.Transcribed interviews were analyzed using Tesch’s eight steps of thematic data analysis.Results The model was described in four phases:relationship phase,working phase,termination phase,and independent phase.The model shows a development process of a student nurse anaesthetist by a nurse anaesthetist facilitator to the mastery of the scope of practice of a nurse anaesthetist.Two themes(six categories)emerged through thematic analysis:the model and guidelines for implementation were found to be appropriate(model and guidelines for implementation are important because of the need for nurse anaesthetist,the model is applicable because it is described as comprehensive,the relationship phase was found to be important and the interdependence between disciplines is imperative,the affirmation that mastery has to be attained by nurse anaesthetists due to the complexity of services rendered),anticipated limitations to the South African nurse anaesthetist(the need to identify complex patients and limitations on the setting and refer to higher level of care,limitations due to red tape).Conclusions This model provides fertile soil to inform and outline the education(curriculum)and practice(scope of practice)and research for nurse anaesthesia practice in South Africa.

Understanding South African mothers’challenges to adhere to exclusive breastfeeding at the workplace:A qualitative study

Objective:This study aimed to gain an in-depth understanding of the experience of South African working mothers in the adherence to exclusive breastfeeding when returning from maternity leave.Methods:The data of the study was collected using face-to-face semi-structured interviews.Eight breastfeeding mothers were purposefully selected from two primary health care clinics in Rustenburg,North West Province,South Africa.The data were coded,categorized,and clustered into themes using Giorgi’s phenomenological analysis.Ethical considerations and measures of trustworthiness were adhered to throughout the study.Results:The findings revealed three themes:a desire for working mothers to continue the adherence to exclusive breastfeeding,workplace support for breastfeeding mothers in the adherence to exclusive breastfeeding,and an unsuitable workplace environment for the adherence to exclusive breastfeeding.Six sub-themes were identified:the need to return to the workplace soon after baby’s birth,psychological responses in the adherence to exclusive breastfeeding,lack of support from employers and coworkers in the adherence to exclusive breastfeeding,lack of or partial implementation of breastfeeding policies in the workplace,the workplace not being supportive for mothers’having to express and the workplace not being supportive for mothers’having to store breastmilk.Conclusion:Based on the findings,South African government should revisit employment policies to support working mothers who need to continue with exclusive breastfeeding after returning from maternity leave.

The Potential of Cassava Biomass as a Feedstock for Sustainable Biogas Production in South Africa

Cassava is currently being investigated for biogas production in South Africa as it offers multiple benefits such as high yields of starch and total dry matter. The chemical constituents of the cassava biomass were determined using standard methods. Using a locally fabricated laboratory batch fermenter, anaerobic digestion was carried out in a 25 L capacity digester maintained at 36 ± 0.5 ℃. Pre-treatment of the cassava biomass with spoilage fungi, Aspergillus niger and PeniciUium species yielded large amounts of fermentable sugars for digestion. Cassava slurry was made and mixed with zebra droppings （2：1 v/v） and loaded into the digester of 20 L working volume. Analysis results showed an increase in most nutrients after pretreatment except for starch which decreased from 76% to 60% as a result of its hydrolysis to fermentable sugars by the spoilage fungi. Theoretical biogas yields were between 0.71 nm3 and 0.75 nm^3 per kg VS （volatile solids） destroyed while the total biogas yields of between 250 nm^3 and 300 nm^3 per kg VS fed into the digester was obtained after 20 days residence time. Cassava is not yet a staple food in some BRICs countries like South Africa and the peels and other by-products of its processing are equally suitable for energy production. The use of cassava will be an alternative feedstock strategy for several rural biogas projects running with cow dungs inside South Africa. In addition, opportunities exist for decentralized, cheaper and socially advantageous bioenergy production from cassava considering that fuel and electricity needs are not satisfied in many rural areas. Finally, the incorporation of cassava anaerobic digestion facility at different scales will deliver additional benefits like the incorporation of nutrients and residual carbon into the land as fertilizer.

Seasonal discharge and chemical flux variations of rivers flowing into the Bayhead canal of Durban Harbour, South Africa

The u Mhlatuzana, u Mbilo and a Manzimnyama river catchments located on the eastern seaboard of the Kwa Zulu-Natal province, South Africa, form the core of urbanization and industrialization, contributing the only natural freshwater inflows to the Bayhead Canal portion of the Durban Harbour. In this study, seasonal discharges and physico–chemical water properties were used to quantitatively determine the material mass transport capacity of the river systems on the basis of hydrographic inputs and chemical loading from the surrounding land use sectors.The mass transport of the total dissolved solids(TDS),ammonia(NH_4), phosphorous(P), aluminum(Al), calcium(Ca), copper(Cu), chromium(Cr), mercury(Hg), potassium(K), magnesium(Mg), sodium(Na), nickel(Ni), lead(Pb), sulphur(S) and vanadium(V) was determined for each river. Results indicated that land use, seasonality and river flow were significant determinants for the material loading in the rivers and the receiving port waters. The spatio-temporal distribution patterns of chemical fluxes indicated that industrial activity associated with the a Manzimnyama canal contributed the most, with regards to TDS, NH_4, Ca, K, Mg, Na, S and V, loading in both wet and dry seasons, as well as Al, Cu, Hg and Pb during the dry season. Similarly, industrial activity associated with the u Mbilo/u Mhlatuzana Canal at the lower reaches accounted for the highest P, Al, Cu and Pb fluxes in the wet season alone. Fluxes of these parameters are used to explain theobserved elemental concentrations and patterns of the receiving port waters of the Bayhead Canal.