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SLOET, Hendrik Albertus Inventory of documents
No full textCOVERAGE1972-1998; 15 files; 87 speeches; 0.30 metrePrivate papers of H.A. Sloet, Director Dagbreek Trust and Perskor Group
DE KLERK, Johannes [Jan] Inventory of documents
No full textCOVERAGE 1941-1969; 185 Files; 12,00 Metres.AUDIO CASSETTES IN ARCA COLLECTION = 1Private papers of J. De Klerk, National Party MPC Transvaal [1949-1955], Senator [1955-1975], Minister Labour [1954-1961], Public Works [1954-1958], Mines [1958-1961], Interior [1961-1966], Immigration [1961], Education, Arts and Science [1961-1968], National Education [1968-1969], Information [1966-1968], father of President F.W. De Klerk
LUTTIG, P.J.H. Inventory of documents
No full textCOVERAGE 1890-1966; 1 File; 0,11 Metre.Private papers of P.J.H. Luttig, MPC, Prieska [1930-1933], MP Victoria West [1933-1938], Calvinia [1943-1953], Ceres [1953-1960]; Senator [1960-1965]
Formation and characterization of novel nanostructured un-doped and Ga-doped ZnO transparent conducting thin films for photoelectrode
No full textIn the present work, Ga-doped ZnO (GZO) thin films and ZnO nanorods (ZNRs) were fabricated for possible use as a transparent conducting oxide (TCO) film and a semiconductor oxide (SC) material, respectively, for photoelectrode component of the dye-sensitized solar cells (DSSCs). The GZO nanoparticles (NPs) were synthesized using the reflux-precipitation method, while ZNRs were grown on glass substrates seeded with an optimized GZO layer by the chemical bath deposition (CBD) method. The material properties of the samples were studied using various techniques.
The X-ray diffraction patterns for all the GZO NPs and ZNRs exhibited a highly crystalline and hexagonal wurtzite structure of ZnO with no impurity phases. The values of the crystallite sizes range from 11 - 28 and 21 - 31 nm for the NPs and ZNRs samples, respectively. Peak shifts to lower diffraction angles from 47.45 - 47.35° with the increase in Ga/Zn solution pH was observed. A similar trend was observed also for other growth and deposition parameters studied. The studies on effects of annealing temperature and Ga-doping levels showed that the average lattice constants ‘a′ and ‘c′ were calculated as a = 3.263 and c = 5.208 Å, showing an increase in trend with the increase in Ga doping levels and annealing temperature. These values are in close range to the bulk ZnO lattice constants shown in the JCPDS card, No. 79-0205 (a = 3.264 and c = 5.219 Å). The XRD analysis revealed that the as-grown ZNRs were preferentially oriented along the c-axis in most cases with relative texture co-efficient values for (002) plane ranging from 0.309 - 0.418 and 0.37 - 0.56 with the increase in CBD growth concentration and growth time, respectively.
The scanning electron microscopy (SEM), images revealed that, at the lower growth pH, the micrographs showed agglomerated tiny GZO NPs that formed on big slabs of nanorods, but fine and enlarged particles on nano-spherical bases formed at the higher pH values. The tiny hexagonal particles for un-annealed samples turned into bigger rods with increasing annealing temperatures. Similarly, the SEM micrographs and atomic force microscopy images of the ZNRs showed an increase in lengths and particle sizes as the growth concentration and time increased. It is important to note that, more regular and orderly nanorods with enhanced morphology and uniformity could be observed with the increase of the growth concentration to 0.05 M and time to 90 min.
The PL results of the samples showed sharp and dominant UV-emission peaks which varied in position between 380 and 390 nm; and relatively smaller and broader deep level peak intensities (centred around 550 nm). The highest intensities of the UV-emission peaks
were observed for GZO NPs prepared at 2 mol% Ga doping, annealing temperature of 300 ºC and 5 pH of growth solution, as well as ZNRs prepared at 0.05 M concentration and 90 min growth time. Interestingly, minor peaks located around 440 nm could also be seen in few samples. It was observed that the emission peaks of ZNRs and GZO NPs generally shifted towards higher wavelengths with the increase in the growth and deposition parameters.
The UV-Vis analysis also demonstrated that the optical properties of the GZO NPs and ZNRs improved with the increase in growth and deposition parameters, as shown by the blue shift of the absorption edge of the reflectance spectra. The band gap energies of the GZO NPs were tuned from around 3.15 to 3.31 eV with the increase in the pH to 5 and Ga doping levels to 2 mol%. However, the band gaps of ZNRs varied between 3.1 and 2.0 eV with the increase in growth concentration and deposition time.
It was observed that the GZO NPs’ sample prepared at 2 mol% Ga doping, 5 pH growth medium and annealed at 300 ºC presented an optimum crystallinity, minimum lattice stress, enhanced luminescence intensity and good optical properties and as such, was deposited on glass substrates to form the seed layer to produce GZO TCO film upon which ZNRs were grown. On the other hand, the sample that was deposited at the CBD growth concentration of 0.05 M and 90 min time presented good crystallization, good optical and luminescence properties with homogenous and well-aligned ZNRs. This could be used as a possible photoanode component of the dye-sensitized solar cell.National Research Foundation (NRF
Nutritional status, knowledge, attitude and practices of patients receiving maintenance hemodialysis in Bloemfontein, South Africa
No full textBackground: Internationally, the nutritional management of patients on maintenance hemodialysis (MHD) poses a challenge. This is the first Sub-Saharan study to focus on knowledge, attitudes and practices (KAP) regarding the renal diet required for patients on MHD.
Methods: A descriptive, cross sectional study was performed during 2017 on 75 participants receiving MHD in Bloemfontein, a mid-sized city in central South Africa. Questionnaires were administered during structured interviews, and anthropometry, pre-dialysis biochemistry and information from the patient files were documented.
Results: The participants were mostly men (70.7); median age, 50.5 years; median education level, Grade 12. The etiology of renal failure included hypertension (37.3 %), diabetes mellitus (DM) (6.7 %), or both (10.7 %). Home-languages were mostly Sesotho (46.7 %) and Afrikaans (4 %), and second languages, English (61.4 %) and Sesotho (18.7 %). Most (64 %) lived in overcrowded conditions, 38.7 % received a social grant, and only 24 % were employed full-time. Furthermore, 41.7 % had an income <R1 500 per month (pm); the median percentage of income available for food per person (pp) pm, was 27.3 % (the suggested in 2017 was 40 %), and 78.9 % were spending <40 % of income pp/pm on food.
Median body mass index (BMI) was 26.4 kg/m2, with 23 % overweight (30 kg/m2) and only 5.3 % underweight (17.0 kg/m2). Most (66.2 %) had a weight-to-height-ratio (WHtR) >0.5, indicating increased risk for metabolic comorbidities. Body fat (BF) percentages were above normal (>85th percentile) for 25.4 %. Yet, 56 % had arm muscle areas (AMA) 25 kg/m2 (indicating overweight), and 57 % (n= 24) had a normal BMI (>18.5 kg/m2 to < 24.9 kg/m2).
Without C-reactive protein (CRP) testing, the low serum albumin levels (<35 g/L) in 49.3 % of participants, as well as hypocholesterolemia (53.3 %, n= 8 out of 15) and low white blood cell counts (WBC) (26.4 %, n= 14), cannot be ascribed to malnutrition with certainty. Yet,
pre-dialysis low serum urea levels (1.8 mmol/L for 25.3 %, and above 1.42 mmol/L for 49.3 %.
Compared to NKF-K/DOQI guidelines, 44.6 % of participants had energy intakes 35 kcal/kg. Similarly, 48.6 % had total protein (TP) intakes 1.3 g/kg. Overall, 40 % had consumed inadequate amounts of HBV protein (75 % of TP) (95 % CI [R4 416.70 ; R19 000.00]), and spent statistically significantly less pp on food (95 % CI [R216.70 ; R1 309.50]).
Overall, 49.4 % had poor combined knowledge (12 mg PO4/g protein) (95 % CI [2.9 % ; 52.5 %]).
Most (60 %) felt negative about the renal diet, and (61.4 %) reported poor adherence practices. Most (77.3 %) reported ≤1 consultation with a dietitian per MHD year (NKF-K/DOQI recommendation: >3).
Conclusion: This sub-Saharan population on MHD presented with substantial overweight and obesity, indicating high risk for cardiovascular complications; yet, excessive body fat levels, masked muscle wasting. Protein intake, particularly, HBV protein intake were below recommendations, and significantly associated with lower income levels. Most participants showed inadequate knowledge (significantly associated with education level and receiving NE in a first or second language), negative attitudes, and poor compliance practices regarding the renal diet and dietitians were inadequately involved in the treatment of these patients
The impact of a physical activity intervention programme on frailty syndrome in elderly citizens in Maseru District, Lesotho
No full textIntroduction: The global elderly population is increasing at an unexpected rate, the majority of which will reside in developing nations. Geriatric diseases such as frailty syndrome are difficult to differentiate from normal ageing. Scientific research into geriatric diseases such as frailty syndrome and the potential impact of interventions, could enable governments (especially those in developing nations) to prepare adequate infrastructure.
Objectives: The following objectives were investigated: cardiovascular fitness (6-minute walk test); upper body strength (arm curl- and handgrip test); lower body strength (chair stand test); flexibility (modified sit and reach test); balance, speed and agility (8-foot up and go test).
Methods: Participant recruitment followed a cross-sectional quantitative design. A pre-test – post-test control group design was used to implement and evaluate whether the physical activity intervention (approximately 12 weeks) could improve frailty.
Baseline testing was performed on 3 groups. Milk group [n=36 (milk intervention only)], both group [n=37 (milk and physical activity intervention)] and control group [n=35 (no intervention)]. A multicomponent physical activity programme was conducted 3 times a week, at low to moderate intensity, for 45 – 60 minutes. Descriptive statistics (namely, medians and percentiles for continuous data and frequencies and percentages for categorical data) were calculated per group. The change from baseline to post intervention, was also calculated per group. The groups were compared (inter-group) by means of 95% confidence intervals.
Results: An inter-group comparison between the groups from baseline to post intervention (95% CI for percentage difference) revealed a statistically significant difference (p=≤0.05) in the lower body muscle strength of the ‘both’ group compared to the milk group and control group respectively. These results indicate that the physical activity intervention could have benefited the participants more than if they had no intervention or if they had the milk only intervention. It is only in the chair stand that the improvement in the “both” group was significant when compared to the milk and the control group, indicating that physical activity was a significant factor in the improvement. For upper body strength (arm curl), a statistically significant difference (p≤0.05) was found in the “both” group when compared to the control group. Since no statistically significant difference was found between the milk and the control group or between the milk and the both group, it is conceivable that the combination of the interventions (milk and physical activity) was more effective for improvement than no intervention at all or either intervention implemented in isolation. In the handgrip, a statistically significant difference (p≤0.05) was found when comparing the milk group to the control group as well as in the “both” group compared to the control group. The significant improvement in the intervention groups (milk and both) compared to the control likely means a combination of the interventions (milk and physical activity) improves upper body strength more than no intervention or the respective interventions in isolation.
The inter-group comparison (95% confidence interval for the percentage difference) from baseline to post intervention showed no statistically significant differences between the groups for cardiovascular endurance, flexibility, balance, speed and agility.
Although frailty status did not improve in the group receiving the milk and physical activity, improvement was observed in all the other variables contributing to the functional performance of the frail elderly.
Conclusion: The physical activity intervention did not improve frailty status. Since under-nutrition can also contribute to the development of sarcopenia; it is conceivable that if frailty was due to malnutrition more than sedentary lifestyle, a nutritional intervention can make a more significant contribution to frailty status than physical activity (such as is suspected in this study). Selecting a frailty scale sensitive enough to measure improvements in a physical activity intervention (a tool possibly lacking in this study) is essential.
Improvement was seen in the functional outcomes investigated, which contribute to the performance of ADLs and quality of life in the elderly. It is notable that of all the fitness components investigated, only muscle strength showed a statistically significant improvement. This is of particular importance as sarcopenia has been identified as a major problem in frailty and muscle strength is crucial in the fight against sarcopenia. Physical activity interventions are more effective in addressing the sedentary lifestyle factor - which is a contributor towards frailty. Once initiated, they can help target sarcopenia, slow gait speed and diminished endurance
VON ABO, C Inventory of documents
No full textCOVERAGE 1958-1982; 1.20 metreFarmer, Bothaville; Played a key role in the founding of NAMP
NATIONAL YOUTH LEAGUE WITBANK Inventory of documents
No full textCOVERAGE 1957-1963; 6 Files; 0,55 Metre.Papers of the National Youth League Witbank
The effects of structure and ligand variations on the luminescence of Europium (III) complexes
No full textThe chemistry of lanthanides has expanded immensely across many scientific fields over the
years and that was mainly due to the rare versatility exhibited by the spectroscopic and
magnetic nature of these metals in the series. With the coordination nature of these
lanthanoids not governed by the orbital directionality, as is the case with transition metals, the
relative coordination chemistry of this series becomes of great interest and therefore is
susceptible to ground breaking science across many scientific disciplines. Europium (III)
metal ion in particular, has been involved in many scientific fields due to its sterling
spectroscopic properties. Its ternary analogues have been extensively employed as emitting
layers in the edifice of optoelectronic devises. Moreover, its applications extend as far as
tailoring active luminescence bioprobes in biomedical sciences which is a vast field with a lot
of other related applications in it. The main interest has always been its red narrow emission
spectral profile which is susceptible to any organic matrix it is submerged in.
The principle aim of this study was to gain insight into the chemistry, coordination and
photoluminescence behaviour of ternary EuIII based complexes. From this idea, it was
decided to synthesize a few novel ligand systems. This include (E)-1-((9-ethylcarbazol-3-
ylimino)methyl)-napthanol, (E)-2-(9-ethylcarbazol-3-yliminomethyl)-6- methoxy phenol,
(E)-2-methoxy-(6-(phenyliminomethyl))-phenol, (E)-1-((2-(pyridin-2-yl)hydrazono) methyl)
naphthalene-2-ol, (E)-2-methoxy-6-((2-(pyridin-2-yl)hydrazono)methyl)phenol, (E)-2-(2-((2-
hydroxynaphthalen-1-yl)methylene)hydrazinyl) quinolin-8-ol and (E)-2-(2-(2-hydroxy-3-
methoxybenzylidene)hydrazinyl) quinolin-8-ol characterized by means of IR, UV/Vis and
NMR (1H, 13C) spectroscopy. Furthermore, the solid state structural characterization was
carried out using single crystal X-ray diffraction spectroscopy for compounds with suitable
single crystals X-ray diffraction collection. However, the intended tailoring of ternary EuIII
complexes with this novel ligand species was not successful. The ligand systems synthesized
were designed with the idea to be potentially biologically active and fluorescent by itself.
They were analysed for photoluminescence properties and were successfully found to be
luminous and are to be sent for cell testing.
A range of ternary EuIII based complexes, of the form [Eu(β-diketone)3 X]
(X = 1,10-phenanthroline), were synthesized by using selected acetyl acetone derivatives
(β-diketone) as parallel ligand system used in this study. The bidentate β-diketone ligands
used are 1,3-Diphenyl-propanedione (DBM), 2) 4,4,4-Trifluoro-1-chlorophenyl-butanedione
(TCPB), 3) 2-Bromo-1,3-diphenyl-propanedione (DBBrM), 4) 3-Chloro-2,4-pentanedione
(DMC), 5) 3,3-Dimethyl-2,4-pentanedione (DMMP), and 6) Benzoic anhydride (BZAN). The
EuIII based analogues with the bidentate β-diketone ligand given above were successfully
synthesized and characterized by means of IR, X-ray diffraction and Elemental Analysis
spectroscopy. These obtained ternary EuIII based complexes are [tris-(4,4,4-Trifluoro-1-
chlorophenyl-butanedione) mono(1,10-phenanthroline) europium(III)], [tris-(2-Bromo-1,3-
diphenyl-propanedione) mono(1,10-phenanthroline) europium(III)], [tris-(1,3-Diphenylpropanedione)
mono (1,10-phenanthroline) europium(III)], [tris-(3-Chloro-2,4-pentanedione)
mono(1,10-phenanthroline) europium(III)], [tris-(2,2,6,6-Tetremethyl-heptanedione)
mono(1,10-phenanthroline) europium(III)], tris-(Benzoic Anhydride)-mono-(1,10-
phenanthroline) europium(III)] and {[hexa-( Benzyl carboxylic acid) bis-(1,10-
phenanthroline) di-europium(III)]-μ-[κ2-O,O’-( benzyl carboxylic acid)]2}. These above
stated ternary EuIII complexes were analysed for photoluminescence and all proved to be
luminous. However, there were significant differences in the spectral identity of these
respective complexes and that was due to the ligand nature coordinated to the EuIII metal ion.
The observed spectral identities are defined in terms of relative Stark splitting of the
complexes which is induced by the symmetry imposed on the EuIII ion by the atomic
orientations around the metal. The atomic orientations around the EuIII metal ion are dictated
by the steric hindrance imposed by the peripheral derivatization on the acetyl acetone back
bone. It was crystallographically deduced that the high quantum yield (82%) of complex
[tris-(4,4,4-Trifluoro-1-chlorophenyl-butanedione) mono(1,10-phenanthroline)
europium(III)] was due to strong binding of the antenna ligand to the metal ion, facilitating
efficient energy transfer to give high luminous efficiency.
There were successful correlations drawn between the photoluminescence and the
crystallographic data obtained of the [Eu(β-diketone)3 X] (X = 1,10-phenanthroline)
complexes. The respective point groups from both disciplines could be matched. However,
the polyhedron constructed for atoms directly bonded to the EuIII metal ion indicates higher
symmetry point groups due to observed polyhedral distortions therein. The correlation of data
from these two scientific disciplines rubber stamp the proof of concept of using the method
detailed in this study in analysis of the site symmetry of the EuIII metal ion in bulk organic
system, UPNP or any other organic system for that matter
Die Missio Trinitatis as katalisator tot versoening en ‘n lewe saam in Suid Afrika
No full textEnglish: 23 Years after democracy in South Africa, people are still alienating more and more
every day. There are also many new conflicts that makes the situation worse.
Therefore, it is necessary to critically reflect on the situation in South Afrika, and on
the dream of reconciliation. There have been attempts, like those of the Truth- and
Reconciliation Commission in South Africa. However, there are still problems. It
seems as if the doctrine of the Trinity, and furthermore, the missio Trinitatis, have not
yet been proposed as decisive solution for the problem of alienation and the
possibility of a life together in South Africa. The missio Trinitatis, with the Trinity
moving in the world, and making the church part of this movement, opens up new
perspectives and possibilities with regards to reconciliation and a life together in
South Africa. Can a new understanding of the Trinity, the Trinitarian movement in the
world and the African context be a solution for the alienation in this country? In this
movement of the missio Trinitatis, a space is created where reconciliation is possible.Afrikaans: 23 jaar na demokrasie in Suid Afrika is mense nog steeds besig om daagliks meer en
meer van mekaar te vervreem. Daar is ook talle nuwe konflikte wat die situasie
vererger. Dit is daarom nodig om krities te reflekteer op die situasie in Suid Afrika, en
oor die droom van versoening. Daar was al talle pogings, soos dié van die Waarheidsen
Versoeningskommissie in Suid Afrika. Daar is egter nog talle uitdagings. Dit wil
voorkom of die leerstuk van die Drie-eenheid, en verder, die missio Trinitatis nog nie
as beslissende oplossing vir die probleem van vervreemding en die moontlikheid van
‘n lewe saam in Suid Afrika dien nie. Die missio Trinitatis, met die Drie-enige God
wat beweeg en wat die kerk in die wêreld saamneem open nuwe perspektiewe en
moontlikhede vir versoening en ‘n lewe saam in Suid Afrika. Kan ‘n nuwe verstaan
van die Drie-eenheid, die Trinitariese beweging in die wêreld en die Afrika konteks
‘n oplossing wees vir die vervreemding van mekaar in hierdie land? In hierdie
beweging van die missio Trinitatis word daar ruimte geskep waar versoening
moontlik is