Small and medium sized enterprises (SMEs) are a definitive driving force of economic stability in the marketplace due to the number of jobs created by the small and medium sized business sector and there is a positive influence on a country’s national economy. While a considerable amount of research focuses on SME sustainability, empirical tests on the factors influencing sustainability of SMEs have not been piloted and researched to the completest prospective. The primary purpose of this study was to identify the determining factors that influence the sustainability of selected small and medium-sized enterprises. The empirical investigation was conducted among 135 SME owners and/-or managers in the Potchefstroom area of the North West province of South Africa. The methodology included the sampling procedure, data collection, questionnaire development and statistical techniques later used due to the nature of responses. Results were analysed with regard to the descriptive statistics and correlations between questions included in the questionnaire. The results of this study concluded that there are certain factors considered as important contributors for SME sustainability. The importance of this study is the contribution of a sustainability framework which will aid SMEs in the management of sustainability within their enterprises. The further development of a SME programme to equip the management members could be derived from the results in an attempt to ensure the encouragement of this very important commercial driver of the economy. / MBA, North-West University, Potchefstroom Campus, 2014

Emergency on-call duties have been highlighted as a key stress factor in newly qualified physiotherapists whose job performance may be affected. The concept of stress relating to on-call work, the general lack of interest or confidence in the respiratory on-call field, and subsequent difficulties with recruitment and retention, pose a difficult problem for managers of services responsible for the maintenance of a competent workforce and a high standard of service provision. Differences in novice and expert physiotherapists’ patient management and clinical reasoning strategies have been previously examined in orthopaedic, neurology, domiciliary and cardiorespiratory fields. However, no such investigations have been undertaken in the field of emergency on-call. The purpose of this study was to determine if differences existed between novice and expert physiotherapists who had by definition differing levels of context-related experience within the emergency on-call environment. This study also aimed to consider what factors may influence their physiotherapy intervention for an acute cardiorespiratory patient. A purpose-designed vignette-based postal questionnaire was administered to 26 emergency on-call providers in New Zealand. The questionnaire sought demographic data, investigated participants’ attitudes towards emergency on-call service provision and presented a vignette-based clinical scenario which asked questions throughout an evolving clinical case scenario. Analysis was performed using the computer software package for social sciences, SPSS for Windows (version 14), results were analysed using descriptive statistics, and significance testing was performed using non-parametric methods. A good response rate was achieved (78.8%; n = 56). Statistically significant differences between novices and experts were determined in scores for confidence, stress, and support required, also in the factors affecting stress levels. Novices are less confident (p = < .0001), more stressed (p = < .001) and require more support than experts (p = < .001). Factors which influenced both novice, and to a lesser extent, expert stress levels when working as emergency on-call physiotherapists, were established. A relationship was determined between confidence and level of support required (r = -.65; p = < .001); confidence and amount of stress felt (r = -.58; p = < .001); and support required and stress felt (r = .47; p = < .001). Some differences were demonstrated between novice and expert physiotherapists in their answers to a clinical case scenario. Although these were not statistically significant, a trend was noted which may reflect the different clinical reasoning strategies of these physiotherapists. There is a need for novices to gain the type of experience which includes independent problem solving and guided reflection; the use of vignette-based case studies may be one method which could be further exploited. The profession is responsible for the provision of better ways to meet the needs of our future emergency on-call workforce. If this is not achieved, other professional groups will be required to fill the gaps and physiotherapy; particularly cardiorespiratory physiotherapy will lose out.

In 1991 a private town for Afrikaners was established on the bank of the Orange River, in the semi-desert of South Africa’s Northern Cape Province. As a deliberately Afrikaans, and thus white, community, the town’s aims and existence are controversial, but both its principles and practicalities are not unique. Endeavouring to build an Afrikaner homeland in multiracial South Africa seems incongruous, signalling a retreat from social heterogeneity as a fact of the contemporary world. It raises questions about what people do following a social, political and economic paradigm shift, and about what is occurring within a country with multiple and contradictory accounts of history and a traumatic recent past. It also means resisting the pressure to deal with the past, and therefore the present, in a certain way. Consequently, the frequent question of whether or not the town as an enterprise, or its residents, are racist, reveals instead a complex ordering of society. Life in Orania is filled with ordinary everyday activities of earning a living, raising and educating children, socialising, and practising religion in a town where Christian principles are explicit, each combining elements of intentionality and contingency. Once superficial similarity between residents can be taken for granted, the focus shifts to the differences between them, which rise and fall in importance, highlighting the circumstantial nature of group solidarity. This raises the question of what the differences within the community are, how deeply they reach, and where fundamental commonalities lie that prompt them to choose to build a future together. For the few hundred people involved in the enterprise, Orania is the only way they think they will have a recognisable future: they fear the demise of Afrikaners as an ethnic group through cultural assimilation or dispersal, emigration, and population decline. Their position of victimhood and vulnerability, shaped by the past, shapes their present actions in turn. Afrikaners’ interpretation of themselves as victims is easily supported by the popular historical narrative that Afrikaners have always struggled against outside authorities to be self-determining. This ethnographic study reveals that Orania is a concrete response to the fear that there may not be a place for Afrikaners in South Africa’s future, in the country to which they feel they belong and where their identity is rooted.

The validity of the Homsey method for heme iron, modified Schricker and sodium pyrophosphate extraction methods for nonheme iron and atomic absorption spectrophotometry (AAS) and ferrozine methods for total iron were determined using spikes of hemoglobin, ground beef baked to different degrees of doneness, proportional beef liver:catfish mixtures and National Institute of Science and Technology reference materials. The mean spike recoveries of 0.0lg and 0.02g Hb in raw beef and raw chicken samples were 96.7% of the heme iron for the Homsey method, 97.9% of the total iron for the ferrozine method, and 85.7% of the total iron for the AAS technique. In ground beef patties baked rare, medium and well-done, the nonheme iron values increased with Heme and nonheme iron values were plotted against beef liver concentrations in the beef liver:catfish mixtures, and the correlation coefficients obtained were 0.994 for the Homsey method, 0.991 for the modified Schricker method, and 0.995 for the sodium pyrophosphate method. Heme iron plus nonheme iron equalled total iron for all the mixtures. Student's t test revealed no significant difference between ferrozine total iron values and NIST-certified concentrations, but the AAS total iron values were significantly (p<.05) The Hornsey method was validated for all samples except well-done beef. The two nonheme iron methods were reliable and accurate. While the fenozine technique was consistent, reliable and accurate, the AAS method was able to detect, on an average, only 80-85% of the total iron present. There was no interference of the sample mineral matrix with the detection ability of the AAS method.

Orientadores: Milton da Costa Lopes Filho, Helena Judith Nussenzveig Lopes / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Matemática Estatística e Computação Científica / Made available in DSpace on 2018-08-25T00:41:15Z (GMT). No. of bitstreams: 1 Albanez_DeboraAparecidaFrancisco_D.pdf: 3117782 bytes, checksum: 4f8e30c3d217ed3a6d26e9924d4df7ab (MD5) Previous issue date: 2014 / Resumo: Motivados pela existênca de um número finito de parâmetros determinantes (graus de liberdade), tais como modos, nós e médias espaciais locais para sistemas dinâmicos dissipativos, principalmente as equações de Navier-Stokes, apresentamos nesta tese um novo algoritmo de assimilação contínua de dados para o modelo tridimensional das equações Navier-Stokes-alpha, o qual consiste na introdução de um tipo geral de operador interpolante de aproximação (construído a partir de medições observacionais) dentro das equações de Navier-Stokes-alpha. O principal resultado garante condições sob a resolução espacial de dimensão finita dos dados coletados, suficientes para que a solução aproximada, construída a partir desses dados coletados, convirja para a referente solução que não conhecemos (realidade física) no tempo. Essas condições são dadas em termos de alguns parâmetros físicos, tais como a viscosidade cinemática, o tamanho do domínio e o termo de força / Abstract: Motivated by the presence of the finite number of determining parameters (degrees of freedom) such as modes, nodes and local spatial averages for dissipative dynamical systems, specially Navier-Stokes equations, we present in this thesis a new continuous data assimilation algorithm for the three-dimensional Navier-Stokes-alpha model, which consists of introducing a general type of approximation interpolation operator, (that is constructed from observational measurements), into the Navier-Stokes-alpha equations. The main result provides conditions on the finite-dimensional spatial resolution of the collected data, sufficient to guarantee that the approximating solution, that is obtained from these collected data, converges to the unkwown reference solution (physical reality) over time. These conditions are given in terms of some physical parameters, such as kinematic viscosity, the size of the domain and the forcing term / Doutorado / Matematica / Doutora em Matemática

Let (Ω, Σ, µ) be a finite measure space and X, a Banach space with continuous dual X*. A scalarly measurable function f: Ω→X is Dunford integrable if for each x* X*, x*f L1(µ). Define the operator Tf. X* → L1(µ) by T(x*) = x*f. Then f is Pettis integrable if and only if this operator is weak*-to-weak continuous. This paper begins with an overview of this function. Work by Robert Huff and Gunnar Stefansson on the operator Tf motivates much of this paper. Conditions that make Tf weak*-to-weak continuous are generalized to weak*-to­weak continuous operators on dual spaces. For instance, if Tf is weakly compact and if there exists a separable subspace D X such that for each x* X*, x*f = x*fχDµ-a.e, then f is Pettis integrable. This nation is generalized to bounded operators T: X* → Y. To say that T is determined by D means that if x*| D = 0, then T (x*) = 0. Determining subspaces are used to help prove certain facts about operators on dual spaces. Attention is given to finding determining subspaces far a given T: X* → Y. The kernel of T and the adjoint T* of T are used to construct determining subspaces for T. For example, if T*(Y*) ∩ X is weak* dense in T*(Y*), then T is determined by T*(Y*) ∩ X. Also if ker(T) is weak* closed in X*, then the annihilator of ker(T) (in X) is the unique minimal determining subspace for T.

Antibodies are soluble proteins produced by the adaptive immune system to bind and counteract invading pathogens. The binding properties of a typical human antibody are determined by the structure of its variable domain, composed of two chains – heavy and light and by the conformation of six loops located on the surface of the variable domain, known as Complementarity Determining Regions (CDRs). In the first chapter, we describe our analysis of the conformational space occupied by five out of six antibody CDRs (L1, L2, L3, H1 and H2) and the development of a novel, length-independent method for grouping these CDRs into structural clusters (canonical forms). We show that using our method we can increase coverage and precision of assigning CDR sequences into clusters. In the next chapter, we describe a method for ranking structural decoys of the CDR-H3 loop. We show that by computationally perturbing CDR-H3 decoys we can improve the performance of existing ranking methods. In the same chapter, we discuss the development of a method for high-throughput assignment of heavy-light chain orientation. The power of the method was demonstrated by assigning orientation to billions of potential Fv sequences. The third Chapter describes the analysis of a large dataset of CDR sequences with the aim of identifying sequence patterns responsible for the loops' structure. Using a neural network methodology, we found several groups of CDR sequences which might be indicative of previously-unseen conformations. In the final results Chapter, we describe how we used the structural knowledge developed throughout the rest of the thesis to create a novel pipeline for computational antibody design. We show that the binders developed using our methodology had similar features to available antibody therapeutics and low predicted propensity to cause an immunogenic response. These results demonstrate the potential for using computational methods for designing high affinity therapeutics with human properties.

This study was an attempt to establish and compare prediction equations for determining a minimum GPA of 2. 00 in the Applied Arts programs at Dixie College. It also attempted to compare the derived predict ion equations used to determine mini mum GPA 1 s in both the Academic Arts and Applied Arts Divisions. The study compared the derived prediction equations used to determine minimum GPA's for each vocational program in the Applied Arts Division. The study attempted to determine and compare t he most reliable predictor in the Academic Arts Division, total Applied Arts Division, and each vocational program in the Applied Arts Division. In conclusion, the thesis illustrates what percent of the total variation of GPA could be accounted for by the derived prediction equations in the Academic Arts Division, total Applied Arts Division, and in each vocational program in the Applied Arts Division. It also determined that the ACT Social Science subtest score proved to be the best single predictor for both the Academic Arts and Applied Arts Divisions at Dixie College as well as for the vocational programs of Architectural Drafting and Airline Stewardess. The ACT Composite score proved to be the best single predictor in the vocational programs of Auto Mechanics, Electronics, and Business Education at Dixie College.

Reptiles exhibit marked diversity in sex-determining mechanisms. Many species exhibit genotypic sex determination (GSD) with male heterogamety (XX females/XY males), others have GSD with female heterogamety (ZW females/ZZ males), and still others exhibit temperature-dependent sex determination (TSD). The distribution of these mechanisms throughout the reptile phylogeny implies evolutionary lability in sex determination, and in some lineages there has been a number of transitions between GSD and TSD. Despite this diversity, GSD and TSD have traditionally been viewed as mutually-exclusive mechanisms of sex determination in reptiles, since there is little evidence for their co-occurrence. Considerable empirical and theoretical effort has been directed towards understanding the adaptive significance of TSD in reptiles. In comparison, there has been little focus on understanding how evolutionary transitions between GSD and TSD occur at a genetic and mechanistic level. I addressed this question by applying both empirical and theoretical approaches to investigate interaction of genotypic and temperature influences in the sex determination of two endemic species of Australian lizards. The three-lined skink, Bassiana duperreyi, has XX/XY chromosomal sex determination, yet a previous investigation reported a significant male bias in the sex ratio of eggs incubated at low temperatures. To enable an explicit test for temperature induced sex reversal in this species, a 185 bp Y chromosome marker was isolated by Amplified Fragment Length Polymorphism (AFLP) analysis. The marker was subsequently converted into a duplex PCR assay that co-amplified a 185 bp (or 92 bp) Y chromosome fragment and a 356 bp fragment of the single-copy nuclear gene C-mos (from both sexes) as a positive control. The accuracy of the PCR sex assay was tested on 78 individuals for which sex reversal was not expected. PCR genotype and sex phenotype were concordant for 96% of the animals. This is one of the very few sex tests developed for a reptile, and the first report of Y chromosome sequence from a reptile. The PCR assay was subsequently applied to genotype hatchlings from both cool (16-7.5C) and warm (22-7.5C) cyclical incubation temperature treatments, and identified sex reversal in 15% of genotypically female (XX) embryos (n=26) from the cool treatment, but no sex reversal in eggs from the warmer treatment (n=35). Thus, low incubation temperatures can over-ride genotypic sex determination in B. duperreyi, indicating that GSD and TSD co-occur in this species. The Central bearded dragon, Pogona vitticeps (Agamidae), has ZZ/ZW chromosomal sex determination, and is a member of a lizard family in which GSD and TSD are both widespread, indicating evolutionary lability in sex determination. AFLP analysis was applied to isolate homologous Z and W chromosome-linked markers (71 bp and 72 bp, respectively) from this species. The AFLP sequences were subsequently extended into larger genomic fragments by a reiterated genome walking procedure, producing three non-overlapping contigs of 1.7 kb, 2.2 kb and 4.5 kb. The latter two fragments were verified as distinct, homologous Z/W chromosome fragments by PCR analyses. An amplified 3 kb fragment of the 4.5 kb contig was physically mapped to metaphase spreads, identifying the W microchromosome, and for the first time in this species, the Z microchromosome. PCR analyses indicated the presence of homologous sequences in other Australian agamid species, including both GSD and TSD species. The isolated sequences should therefore prove useful as a comparative genomic tool for investigating the genomic changes that have occurred in evolutionary transitions between sexdetermining mechanisms in agamids, by enabling the identification of chromosomes in TSD species that are homologous to the sex chromosomes of P. vitticeps. The isolated sequences were further converted into a duplex DNA sex assay that co-amplified a 224 bp W chromosome fragment and a 963 bp positive control fragment in both sexes. This PCR assay diagnosed chromosomal sex in three Pogona species, but was not effective outside the genus. Incubation treatment of P. vitticeps eggs revealed a strong and increasing female bias at high constant temperatures (34-36C), but an unbiased sex ratio between 22-32C. Hatchlings from three clutches split between 28C and 34 or 36C incubation treatments were genotyped with the W chromosome AFLP marker. At 28C, the sex ratio was 1:1 but the high temperature treatments produced 2 males and 33 females. All but one of the 30 lizards (97%) incubated at 28C had concordant sex phenotype and genotype, but only 18 of 35 animals (51%) from the high temperature treatment were concordant. All discordant animals were genotypic males (ZZ) that developed as females. Thus, temperature and genotypic influences can interact to determine sex in P. vitticeps. These empirical findings for B. duperreyi and P. vitticeps were extended into a novel theory for the evolution of sex-determining mechanisms in reptiles, working within the framework that species with temperature-induced reversal of chromosomal sex determination are a window to transitional stages of evolution between GSD and TSD. A model was derived from the observation that in both lizards, an extreme of incubation temperature causes sex reversal of the homogametic genotype. In this model, the strength of a genetic regulatory signal for sex determination must exceed a threshold for development of the homogametic sex to occur (male in Pogona, female in Bassiana). The strength of this signal is also temperature-sensitive, so diminishes at extremes of temperature. Simulation modelling demonstrated that increasing the relative magnitude of the threshold for sexual development can cause evolutionary transitions between GSD and TSD. Even more remarkably, decreasing the relative magnitude of the threshold value causes an evolutionary transition between female and male heterogametic GSD. Quantitative adjustment of a single model parameter (the threshold value) thus charts a continuous evolutionary pathway between the three principal mechanisms of sex determination in reptiles (XX/XY-ZZ/ZW-TSD), which were previously considered to be qualitatively distinct mechanisms. The experimental demonstration of temperature-induced reversal of chromosomal sex determination in both B. duperreyi and P. vitticeps presents a challenge to the traditional view that reptilian sex determination is strictly dichotomous (GSD or TSD), and suggests instead that sex determination in reptiles consists of a continuum of systems of interaction between genotypic and temperature influences. Simulation modelling provided solid theoretical support for this proposition, demonstrating that transitions along this continuum are effected simply through shifts in the mean population value for the sex-determining threshold, without requiring substantial genotypic innovation. An important implication of this theory is that transitions between XX/XY and ZZ/ZW modes of GSD may retain the same sex chromosome pair, and the same primary sexdetermining gene, in contrast to previous models for heterogametic transitions. A more immediate implication of these findings is that many reptile species believed to have strict TSD (in particular, lizards and crocodilians), may in fact have a sex-determining system of GSD-TSD interaction, where there is an equilibrium between GSD and TSD individuals within the population.

We study three problems related to searching and sorting in multisets in the cache-oblivious model: Finding the most frequent element (the mode), duplicate elimination and finally multi-sorting. We are interested in minimizing the cache complexity (or number of cache misses) of algorithms for these problems in the context under which the cache size and block size are unknown. We start by showing the lower bounds in the comparison model. Then we present the lower bounds in the cache-aware model, which are also the lower bounds in the cache-oblivious model. We consider the input multiset of size <i>N</i> with multiplicities <i>N</i>₁,. . . , <i>N_k</i>. The lower bound for the cache complexity of determining the mode is &Omega;({<i>N</i> over <i>B</i>} log {<i>M</i> over <i>B</i>} {<i>N</i> over <i>fB</i>}) where &fnof; is the frequency of the mode and <i>M</i>, <i>B</i> are the cache size and block size respectively. Cache complexities of duplicate removal and multi-sorting have lower bounds of &Omega;({<i>N</i> over <i>B</i>} log {<i>M</i> over <i>B</i>} {<i>N</i> over <i>B</i>} - £{<i>k</i> over <i>i</i>}=1{<i>N_i</i> over <i>B</i>}log {<i>M</i> over <i>B</i>} {<i>N_i</i> over <i>B</i>}). We present two deterministic approaches to give algorithms: selection and distribution. The algorithms with these deterministic approaches differ from the lower bounds by at most an additive term of {<i>N</i> over <i>B</i>} loglog <i>M</i>. However, since loglog <i>M</i> is very small in real applications, the gap is tiny. Nevertheless, the ideas of our deterministic algorithms can be used to design cache-aware algorithms for these problems. The algorithms turn out to be simpler than the previously-known cache-aware algorithms for these problems. Another approach to design algorithms for these problems is the probabilistic approach. In contrast to the deterministic algorithms, our randomized cache-oblivious algorithms are all optimal and their cache complexities exactly match the lower bounds. All of our algorithms are within a constant factor of optimal in terms of the number of comparisons they perform.