269 research outputs found
Die reg van die homoseksuele ouer om beheer en toesig oor 'n kind te verkry in die lig van die bepalings van die Grondwet
The political struggle leading up to the Dutch Constitution of 19831 is an empirical theoretical relevant case. A particular theoretical point of view (called the theoretical perspective of scientific legal intervention) appears to be important with respect to knowledge about contitution building. A preponderating identical habitus of constitutional law intervention was characteristic for all political actors involved on the Dutch national level. In revising the Dutch Constitution of 1983 these actors have been influenced by the international context. However, 'the' international context does not exist. Instead there have been four international politically relevant contexts in the case of the Netherlands between 1945 and 1983. These contexts provoked national political issues and could have a strong political impact
Ironie in die Johaimesevangelie
Irony in the Gospel of JohnAn exponent of literary theory and criticism described the shift of focus from the text to the reader as a revolution. One of the main features of irony is the intensive involvement of the reader. As far as John is concerned, some scholars are convinced that 'In the Fourth Gospel theology is irony'. This may be an exaggeration, but emphasises the need to ascertain to v/hat extent irony is used in John and what contribution the study of irony in John can make to the better understanding of themessage of the Gospel. In order to answer these questions, one must firstdetermine what irony is, how it functions and how it can be detected in a text. This article is an attempt in this direction
Microsatellite markers reveal low genetic differentiation among southern African Camelus dromedarius populations
We report new demographic and genetic data on southern African camel (Camelus dromedarius) populations. Results from questionnaires on demography indicated that approximately 476 camels were extant in South Africa, Namibia and Botswana in 2003. We have sampled 234 camels for genetic analysis using a microsatellite marker set consisting of 12 loci. Results indicated little differentiation between camels from southern Africa, the Sudan or an outgroup from the family Camelidae, the alpaca (Lama pacos). Analysis of molecular variance (AMOVA) showed that -0.09% of total variation reside between species, 0.26% between the two southern African camel populations and 99.83% within populations. A coefficient of population differentiation (RST) indicated low levels of differentiation between southern African camel populations, with no specific pattern observed in pair-wise comparisons of 16 populations. An assignment test conformed to known population histories and provided additional support for the hypothesis of low differentiation between populations. There was no evidence of loss of genetic diversity in any individual population. Parentage analysis confirmed the utility of the microsatellite marker set for elucidating uncertain paternity. The results are discussed with reference to the management history of camels in the southern African region and the importance of population and parentage verification in the light of the many historic translocations. Keywords: Camel; genetic differentiation; Camelus dromedaries; genetic variation; microsatellites South African Journal of Animal Sciences Vol. 35 (3) 2005: pp.152-16
Uptake and transport of novel amphiphilic polyelectrolyte-insulin nanocomplexes by caco-2 cells - towards oral insulin
âThe original publication is available at www.springerlink.comâ. Copyright SpringerPurpose: The influence of polymer architecture on cellular uptake and transport across Caco-2 cells of novel amphiphilic polyelectrolyte-insulin nanocomplexes was investigated. Method: Polyallylamine (PAA) (15 kDa) was grafted with palmitoyl chains (Pa) and subsequently modified with quaternary ammonium moieties (QPa). These two amphiphilic polyelectrolytes (APs) were tagged with rhodamine and their uptake by Caco-2 cells or their polyelectrolyte complexes (PECs) with fluorescein isothiocyanate-insulin (FITC-insulin) uptake were investigated using fluorescence microscopy. The integrity of the monolayer was determined by measurement of transepithelial electrical resistance (TEER). Insulin transport through Caco-2 monolayers was determined during TEER experiments. Result: Pa and insulin were co-localised in the cell membranes while QPa complexes were found within the cytoplasm. QPa complex uptake was not affected by calcium, cytochalasin D or nocodazole. Uptake was reduced by co-incubation with sodium azide, an active transport inhibitor. Both polymers opened tight junctions reversibly where the TEER values fell by up to 35 % within 30 minutes incubation with Caco-2 cells. Insulin transport through monolayers increased when QPa was used (0.27 ngmL-1 of insulin in basal compartment) compared to Pa (0.14 ngmL-1 of insulin in basal compartment) after 2 hours. Conclusion: These APs have been shown to be taken up by Caco-2 cells and reversibly open tight cell junctions. Further work is required to optimise these formulations with a view to maximising their potential to facilitate oral delivery of insulin.Peer reviewe
Soil properties of bare patches in rangelands of South African's grasslands
A loss of grassy cover accompanied by the development of bare soil patches, are the most notable forms of rangeland degradation in grasslands of South Africa. Concerns are growing over the threat of loss of nutritious perennial grass species and the lack of regrowth of the bare patches. Grazing and different rangeland tenure systems -communal and freehold, which is equal to continuous and rotational grazing system - are considered to be of major importance for rangeland degradation. The continuous grazing system is seen to be more affected, but the development of bare patches is not restricted to communal land. We hypothesized that (1) soil properties of bare patches in South AfricaÂŽs grasslands are not different in different tenure systems, and (2) soil properties differ with size of bare patches, where big patches are more degraded.
To test this, we sampled soils at communal and commercial land in the Thaba Nchu area of South Africa with the following design: we selected three farms per tenure system, 6 randomly chosen plots (100x100m) per farm, and within these plots we sampled 5 bare patches of different sizes (0-10 cm) per plot, where the soil sample (3 replicates) were taken out of the middle of the bare patch. Additionally, soils of adjacent grass were sampled. The results showed that in total, there were more bare patches in continuous grazing systems, evaluated by aerial pictures, but we couldnÂŽt find any differences in bulk density and carbon stocks, between the tenure systems. Additionally, and surprisingly, we found no significant differences in soil organic carbon stocks between bare soil samples and grass samples. There was no clear relationship between bare patch size and nutrient contents. Other nutrients like phosphor were significantly enlarged at the bare patch compared to the grass samples. According to our results, we conclude, that the bare patches seem to develop in different pathways: i) along tracks of grazing animals, (ii) around termite hills, where the termite construction seems to be an initial starting point of bare patches and (iii) on staying and lying places of the grazing animals, which aslo explain the higher nutrient contents at the bare patches
Identifying sequence variation in cation channel sperm associated genes in Cape mountain zebra (Equus zebra zebra)
The Cape mountain zebra (Equus zebra zebra) has recovered from near extinction over more than eight decades. While their numbers have increased, populations remain isolated with low genetic diversity. With more than 75 new populations being founded and more than 4800 extant animals, conservation management strategies are being implemented to mitigate risk of losses in genetic diversity and reproductive fitness. One objective is to identify reproductive characteristics that may improve population growth. Cation channel sperm (CatSper) genes play an important role in hyperactivation of sperm during fertilization. Mutations in these genes lead to reduced fertility and even infertility. Ten male zebras were sampled from a group that were translocated in 2016 in order to found a new population. Single nucleotide polymorphisms (SNPs) were identified in three of the CatSper genes (1 - 3). Lack of variation was observed in all exons, with only four SNPs being identified in the intronic regions in close proximity to exons 1, 2, 7, 8, and 9 of CatSper 1. These results may contribute to the pre-identification of males for new founder populations to ensure population growth and viability, and may be a useful tool for selection against low-producing individuals
Gene flow and population structure of a solitary top carnivore in a human-dominated landscape.
While African leopard populations are considered to be continuous as demonstrated by their high genetic variation, the southernmost leopard population exists in the Eastern and Western Cape, South Africa, where anthropogenic activities may be affecting this population's structure. Little is known about the elusive, last free-roaming top predator in the region and this study is the first to report on leopard population structuring using nuclear DNA. By analyzing 14 microsatellite markers from 40 leopard tissue samples, we aimed to understand the populations' structure, genetic distance, and gene flow (Nm). Our results, based on spatially explicit analysis with Bayesian methods, indicate that leopards in the region exist in a fragmented population structure with lower than expected genetic diversity. Three population groups were identified, between which low to moderate levels of gene flow were observed (Nm 0.5 to 3.6). One subpopulation exhibited low genetic differentiation, suggesting a continuous population structure, while the remaining two appear to be less connected, with low emigration and immigration between these populations. Therefore, genetic barriers are present between the subpopulations, and while leopards in the study region may function as a metapopulation, anthropogenic activities threaten to decrease habitat and movement further. Our results indicate that the leopard population may become isolated within a few generations and suggest that management actions should aim to increase habitat connectivity and reduce human-carnivore conflict. Understanding genetic diversity and connectivity of populations has important conservation implications that can highlight management of priority populations to reverse the effects of human-caused extinctions
Shell Structures and Chaos in Deformed Nuclei and Large Metallic Clusters
A reflection-asymmetric deformed oscillator potential is analysed from the
classical and quantum mechanical point of view. The connection between
occurrence of shell structures and classical periodic orbits is studied using
the ''removal of resonances method'' in a classical analysis. In this
approximation, the effective single particle potential becomes separable and
the frequencies of the classical trajectories are easily determined. It turns
out that the winding numbers calculated in this way are in good agreement with
the ones found from the corresponding quantum mechanical spectrum using the
particle number dependence of the fluctuating part of the total energy. When
the octupole term is switched on it is found that prolate shapes are stable
against chaos whereas spherical and oblate cases become chaotic. An attempt is
made to explain this difference in the quantum mechanical context by looking at
the distribution of exceptional points which results from the matrix structure
of the respective Hamiltonians. In a similar way we analyse the modified
Nilsson model and discuss its consequences for nuclei and metallic clusters.Comment: to appear in Physica Scripta., CNLS-94-02, a talk given at the Nobel
sponsored conference SELMA 94 "New Nuclear Phenomena in the Vicinity of
Closed Shell" (Stockholm and Uppsala, 29 Aug.- 3 Sept. 1994
âClosing the door on protection? Exploring the impact of lockdown upon children and young peopleâs services in the UKâ.
Purpose: The article uses two case studies to explore the impact of repeated lockdowns upon the delivery of child protection and youth offending services in the UK.
Design/methodology/approach: The article draws upon two in-depth interviews - drawn from a global mixed-methods project on the Covid-19 pandemic - with a Child Protection Officer in the North West and a Youth Offending Worker from the West Midlands.
Findings: The two case studies demonstrate that already-austerity hit Childrenâs and Young Peopleâs services moved almost all their service delivery online, preventing frontline child practitioners and youth offending workers from properly assessing, monitoring, and supporting vulnerable children and young people. In both case studies, the participants claim that repeated lockdowns have done irreversible damage to their client relationships; jeopardised potential progress out of vulnerable situations; and heightened risks for many of their client group. Notwithstanding, these two workers faced pressure to adhere to both the Covid-19 regulations and health and safety protocols. While our participants felt this affected the quality of their engagement with young people, they aired frustrations at other colleagues who, they suggested, appeared âcontentâ to have minimal contact with their client group. Nevertheless, the two workers demonstrated admirable resilience as they strove to deliver essential support to their clients. In a climate of local authority debt, school closures and further challenges to information sharing because of the pandemic, these two workers doubt support systems will return to pre-Covid standards and expect online working to continue, to the detriment of vulnerable children and young people. Essentially, these two examples indicate how Covid-19 measures close the door on protecting vulnerable children and young people.
Originality: The article builds upon the emerging empirical evidence on how lockdowns have impacted children and young peopleâs services.
Practical implications: The limited yet detailed findings potentially highlight important deficits in the social care sector in general.
Social implications: Though ungeneralizable, we suggest our participantsâ experiences might be replicated in some other child protection and youth offending services across the UK
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