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This paper analysed the economic efficiency of small-scale tomato farmers in the Greater Letaba municipality of South Africa’s Limpopo Province. Primary data were collected from 68 tomato farmers based on structured questionnaires and using convenience and purposive sampling procedures. The Cobb-Douglas production function was used to analyse the level of economic efficiency. The study utilised the output approach, where the output achieved by the farmers is compared to the maximum output attainable using the given inputs. The empirical results reveal that mean technical, allocative, and economic efficiency levels are at 0.95, 0.41 and 0.39, respectively. The study also found that land (farm size), seedlings, labour, pesticides and water have a positively significant relationship with the production of tomatoes in the study area. Therefore, it is recommended that the Department of Agriculture, Land Reform and Rural Development provide farmers with enough extension services by employing more extension personnel. Government programmes such as the Comprehensive Agricultural Support Programme should be intensified – through the pillar of training and capacity building – to reach the small-scale farmers in the municipality, whereby farmers should be provided with training on the recommended minimum and maximum application of inputs like pesticides, fertilisers, seedlings and water in tomato production.

Objective. Conduction-induced heart failure in patients with left bundle branch block (LBBB) can benefit from cardiac resynchronization therapy (CRT). However, some patients are non-responders to the therapy with one contributing factor being poor optimization of the atrioventricular (AV) pacing delay. In this study, we have investigated the pacing-induced changes in the seismocardiogram (SCG). Approach. 14 patients with heart failure, LBBB, and CRT were included. SCG was recorded with pacing turned on and off. Based on a mean SCG heartbeat from each patient, fiducial points were annotated, and cardiac timing intervals (CTI) and amplitudes were derived. These were compared between the CRT group and a group of healthy normal subjects (n = 14). Echocardiography was also used to derive CTI. Intervals derived from the SCG and echocardiogram were correlated. Main results. The isovolumetric contraction time (IVCT) derived from SCG was significantly shorter in the CRT group when the pacemaker was turned on (63.2–52.6 ms, p = 0.027). The first peak-to-peak amplitude in the systolic complex was significantly larger with the pacemaker turned on (p = 0.002), as well as the ∣max-min∣ amplitude in the systolic complex (p = 0.003). Isovolumetric relaxation time and left ventricular ejection time (LVET) were not significantly different between pacemaker settings. Compared to normal subjects, IVCT was significantly prolonged with the pacemaker turned off. All amplitudes were significantly larger in the healthy subject group. IVCT and LVET derived from SCG were significantly correlated to the echocardiogram. Significance. IVCT shortened and SCG amplitudes increased in response to CRT, indicating a more efficient ventricular contraction. This demonstrates the possibility to detect cardio-mechanic changes in response to treatment with the SCG. However, for the patients the systolic part of the SCG was abnormal and difficult to characterize, raising concerns about the correct interpretation of the SCG.

OBJECTIVES: Previous studies have observed an increase in low frequency diastolic heart sounds in patients with coronary artery disease (CAD). The aim was to develop and validate a diagnostic, computerized acoustic CAD-score based on heart sounds for the non-invasive detection of CAD.METHODS: Prospective study enrolling 463 patients referred for elective coronary angiography. Pre-procedure non-invasive recordings of heart sounds were obtained using a novel acoustic sensor. A CAD-score was defined as the power ratio between the 10-90 Hz frequency spectrum and the 90-300 Hz frequency spectrum of the mid-diastolic heart sound. Quantitative coronary angiography analysis was performed by a blinded core laboratory and patients grouped according to the results: obstructive CAD defined by the presence of at least one ≥ 50% stenosis, non-obstructive CAD as patients with a maximal stenosis in the 25-50% interval and non-CAD as no coronary lesions exceeding 25%. We excluded patients with potential confounders or incomplete data (n = 245). To avoid over-fitting the final cohort of 218 patients was randomly divided into to a training group for development (n = 127) and a validation group (n = 91).RESULTS: In both the training and the validation group the CAD-score was significantly increased in CAD patients compared to non-CAD patients (p < 0.0001). In the validation group the area under the receiver-operating curve was 77% (95% CI 63-91%). Sensitivity was 71% (95% CI 59-82%) and specificity 64% (95% CI 45-83%).CONCLUSION: The acoustic CAD-score is a new, inexpensive, non-invasive method to detect CAD, which may supplement clinical risk stratification and reduce the need for subsequent non-invasive and invasive testing.

The principle of open access is gaining currency and is not often questioned any more.The discussion has shifted to practical issues of bringing about open access, of which there are many. This shift, however, is progress for open access. Understanding is growing of the exact nature of practical problems, of how the open access publishing model works and what the underlying issues are that objections to the model actually address. Based on a paper presented at the UKSG Seminar ‘Scientific Publications: Free for all?’, The Geological Society, London,Tuesday 23 November 2004.

In the debate about the National Institutes of Health (NIH) proposals, we have seen and heard much concern expressed for the health of the publishing industry and the health of societies with a publishing program. Most arguments seem to center on these issues. And they are very important, of course, especially to the publishing organizations concerned, be they scholarly societies or commercial publishers. They fear for the demise of their subscription-based model and the seemingly secure income streams it generates. Societies argue that they need the income from publishing to sustain the other important activities that they are engaged in, such as the awarding of scholarships, the organizing of conferences, public outreach, and educational programs. Commercial publishers cannot argue that losing revenue means having to stop charitable activities, but they gratefully regard societies as a convenient bulwark behind which they can safely shelter from the effects of any criticism. Societies, after all, are part of the scientific community and will, as such, be treated with much more care than commercial publishers by those who want to change the way of scientific publishing, or so the theory goes. And of course, there is some justification for that. But curiously, there is something missing from the debate. We heard little about the health and effectiveness of science. Yet that has to be the prime concern. Publishers and scholarly societies derive their raison d'être from serving science. It is the obligation of all participants in this debate to put science first. That does not seem to happen, however. If the concerns of science were put first, and the business of providing a service to the world of research were to follow rather than take pole position, we could take the discussion further, and debate as to how science is best served. There will be different ideas about that, of course. The vantage point of a scholarly society, including its perspective on business, is bound to be different from that of a commercial publisher. But a rich and frank exchange of those ideas can only benefit the outcome. Alas, an opportunity seems to have been missed by many in the furor surrounding the NIH proposals.

The argument that publicly funded research should be publicly available is a valid one, but it cannot be the most important one in the discussion as to whether research should be freely accessible. The overriding argument is that freely accessible research optimises the scientific process as well as its ‘translation’ into societal benefits. Free access, or ‘open access’ as it is widely called, can be brought about by making full use of the technologies available to the world, particularly the internet, but it does need a change in traditional economic models of publishing.

Decision-makers are increasingly required to assess the value created by complex physical systems over their entire life cycle. The commonly applied Life Cycle Costing approach fails to fully capture value, as it is primarily aimed at costs, takes a reductionist approach, and does not account for continuously changing industrial environments. To address these shortcomings, the Life Cycle Valuation methodology is proposed, designed as a hybrid of LCC and Life Cycle Assessment. LCV facilitates the assessment of costs and benefits from multiple complementary perspectives and can be tailored to specific decision contexts, as demonstrated by applying LCV during Asset Management decision-making.

In this thesis I focussed on a mutualistic symbiosis; the fungus-growing termites and their fungal symbiont Termitomyces. The origin of this symbiosis between fungus-growing termites (Macrotermitinae) and Basidiomycete fungi of the genus Termitomyces has been estimated at approximately 30 million years ago in the rainforests of central Africa. The symbiosis has a single origin with no known reversals of both partners to a non-symbiotic state. The single origin of fungiculture and the absence of any reversals of the fungus to a free-living state are puzzling as both parties have retained independent reproduction and dispersal, which could potentially de-stabilize the symbiosis by leaving room for the fungus to escape or for the termite to domesticate more than one symbiont. For this thesis I studied the biology of the closest relatives of Termitomyces in order to reconstruct the biology of its ancestor. Furthermore, I studied the phylogeny and biology of the genus Termitomyces in more detail to understand what made the genus so diverse and successful.In order to make inferences on the events leading to domestication of Termitomyces a well-supported phylogeny is needed. In chapter 2 I performed a phylogenomic analysis of 25 species of Termitomyces and 21 related non-domesticated species. To reconstruct the biology of the ancestor of Termitomyces I also studied the biology of the non-domesticated species. The phylogenomic analysis recovered the insect-faecal associated genus Arthromyces as the sister group of Termitomyces. I found that Arthromyces shares a suite of traits with Termitomyces, indicating that their common ancestor also possessed these traits. I hypothesize that this set of traits predisposed the ancestor of Termitomyces towards domestication.One of traits found in many species related to Termitomyces is the production of asexual spores (conidia). I hypothesized that these conidia play a role in local dispersal of the fungus and potentially in faster substrate colonisation. In chapter 3 I conducted a population study on the insect-faecal associated and conidia-producing fungus Blastosporella zonata. I sequenced two highly variable genetic markers of 21 collections of B. zonata mushrooms at three collection sites in cloud forests near Murillo, Colombia. I found signatures of clonality within a collection site but usually not between sites, which indicates that conidia are mainly used for local dispersal. There was genetic diversity as well, particularly between collection sites, indicating an important role for sexual spores (basidiospores) and resulting in unique genotypes of most collections. Unexpectedly. by reconstructing fungal haplotypes and subsequent phylogenetic analysis on these, I found evidence for the existence of two cryptic biological species in B. zonata.In the studies I conducted in chapter 2 I used five unidentified species of Tephrocybe. As the morphological descriptions as well as the DNA sequences of these species did not match any species already known, I chose to describe those species in chapter 4. The taxonomy for these five new species was challenging as morphological traits and biogeography did not align with the molecular phylogeny. Therefore, I discussed several alternative options to keep genera monophyletic. This ultimately led to the erection of four new genera: Australocybe, Nigrocarnea, Phaeotephrocybe and Praearthromyces.The genus Termitomyces contains about 40 described species and harbours a lot of morphological diversity. Probably many species of Termitomyces remain undescribed as there is a strong bias towards the description of species that regularly produce mushrooms. In chapter 5 I assembled a large dataset of over 1500 DNA sequences of Termitomyces and used species delimitation software to sort sequences into hypothetical species based on the barcoding gap within the dataset. Using this approach, I recovered 87 phylogenetic species and for these species I collected specimen metadata such as continent of origin and termite host genus. A phylogenetic reconstruction of the 87 species revealed five main symbiont groups which corresponded with the five largest fungus-growing termite genera. I identified several factors which could be involved in speciation: fruiting mode (underground or aboveground), geographic separation, symbiont transmission mode and suppression of mushroom formation by the host termite. Finally, I demonstrated that mushroom morphology does not correlate with phylogeny and therefore, without additional support of molecular data, is not useful for taxonomy in this genus.Uniparental vertical transmission of symbionts is an important factor in aligning reproductive interests of host and symbiont and thus stabilizing the symbiosis. In fungus-growing termites, horizontal transmission is the predominant transmission mode, but uniparental vertical transmission has evolved via the female reproductives of the genus Microtermes and via the male reproductives of the species M. bellicosus. In chapter 6 I studied populations of Microtermes and their symbionts in South Africa. I found high genetic diversity in symbiont populations and low host-specificity, which indicates that frequent horizontal symbiont exchange occurs as well as sexual reproduction, despite the absence of mushrooms of these species. I therefore argue that Microtermes species regularly acquire symbionts associated with species of other genera that do not suppress mushroom formation, such as species of the genus Ancistrotermes.New species of mushroom-forming fungi are often described based on morphological features of the mushroom. In the genus Termitomyces this has caused a heavy bias towards the description of species, which regularly produce mushrooms, leaving species that rarely or infrequently fruit undescribed. In chapter 7 I describe, for the first time in this genus, a species of Termitomyces with no reported naturally produced mushrooms, based on DNA sequence evidence, biological data and asexual features.In chapter 8, I discuss how investigating and understanding the biology of species closely related to fungal symbionts can assist in reconstructing the biology of the ancestor and thereby determine conditions that facilitated fungal domestication by an insect. Although my research focused on a specific group of fungus-growing insects, the fungus-growing termites, I discuss how my approach can be applied to different unrelated groups of fungus-growing insects as well. Finally I discuss how my work not only offers significant contributions to the knowledge on the origin and subsequent evolution of fungiculture in termites, but also contributed to general fundamental knowledge of mutualistic symbioses in general. &nbsp

The study aims to estimate empirically the relationship between economic growth and unemployment rate in Limpopo Province of South Africa. The analysis used quarterly data covering the period 2008-2018 which was obtained from Statistics South Africa. The study employed, difference model, dynamic model, and granger causality test for data analysis, in order to consider both, short term and long term possible relationship Based on the difference model estimation of the coefficient was done and the coefficient was found to be -0.22. From Granger causality test, causal relationship between these two variables doesn’t exist meaning that change in the growth rate of real GDP doesn’t cause change in the rate of unemployment and vice-versa. Inapplicable of the law indicates that a cyclical recovery will not be accompanied by reduction of unemployment. Furthermore, this might reflect the sizable structural and/or frictional component of unemployment in Limpopo Province. Lastly, the country's economic policies have not been suitable for fostering development that can reduce unemployment and this could be due to lack of appropriate composition of public sector and private sector.

Human values—life goals—guide our attitudes and actions. Brands such as Patagonia, TOMS, Warby Parker, Chobani, and Nike successfully position their marketing around human values such as safety, harmony, seeking pleasure, or social welfare. Evidently, consumers attach importance to brands whose values align with their own values. However, the alignment of values (value congruence) and the resulting effects on (re)purchasing behavior are scarcely discussed in the marketing literature. The effects of “traits” and “functional congruence” on purchasing behavior receive considerably more attention. Since human values are conceptually distinct from personality traits, the following question is posed: What is the role of value congruence in the process of consumer brand selection compared with that of trait and functional congruence. An online survey (N = 1182) is conducted to study the effects of these different types of congruence on re-purchase intentions for a range of product categories. Multiple regression and mediation analyses reveal that value congruence is a significant predictor of re-purchase intentions and that it is more important than trait congruence for the categories of services and durables, but not for consumables. This study offers insights into when brand marketing should be aligned with personality traits and human values, respectively.

Faculty of 1000 is a new reviewing, evaluation and rating system of primary scientific papers in the area of biology, produced by Biology Reports Limited and published by BioMed Central Limited (www.biomedcentral.com). Both companies are part of The Current Science Group. The service will identify the current most interesting and most important research papers in biology, picked by a group of over 1000 leading international researchers from any journal, and provide reasons why these articles are the most interesting and important. The service is dynamic, updated every day, but it also keeps an archive of all listings, fully accessible and searchable for subscribers.

Asset Life Cycle Management aims to maximize the value realized from physical assets over their complete lifetime. Over the years, the operation and maintenance of the assets must continually be adapted to changes in goals and context. In an earlier publication, we proposed the Lifetime Impact Identification Analysis to identify such changes. This paper tests this method through an application at two different companies. The method proved to result in a shared and integral overview of long-term challenges and opportunities for the asset, based on experts discussing the asset's future from a technical, economic, compliance, commercial and organizational perspective.

In the capital-intensive industry, maintenance expenditures can add up to several times the initial investment. In order to be competitive in their business, owners and users of these capital goods have to take into account the total life cycle cost at investment (e.g. the lifespan of a capital is often more than several decades), the renewal decisions for their installations and the logistic management of the spare parts. Erroneous or unstructured initial spare parts assortment decision-making part of the logistic management can lead to undesired downtime and increases the risk of obsolete or unavailable components. Decision making is complicated by non-existent data in the early design phase and several information management problems. Based on a case study at Netherlands Railways (the largest maintainer of rolling stock in the Netherlands) and literature review a Decision Support Model to structure and improve the data gathering for more effective initial spare part assortment decision making is proposed.

Plants manipulate their rhizosphere community in a species and even a plant life stage-dependent manner. In essence plants select, promote and (de)activate directly the local bacterial and fungal community, and indirectly representatives of the next trophic level, protists and nematodes. By doing so, plants enlarge the pool of bioavailable nutrients and maximize local disease suppressiveness within the boundaries set by the nature of the local microbial community. MiSeq sequencing of specific variable regions of the 16S or 18S ribosomal DNA (rDNA) is widely used to map microbial shifts. As current RNA extraction procedures are time-consuming and expensive, the rRNA-based characterization of the active microbial community is taken along less frequently. Recently, we developed a relatively fast and affordable protocol for the simultaneous extraction of rDNA and rRNA from soil. Here, we investigated the long-term impact of three type of soil management, two conventional and an organic regime, on soil biota in fields naturally infested with the Columbian root-knot nematode Meloidogyne chitwoodi with pea (Pisum sativum) as the main crop. For all soil samples, large differences were observed between resident (rDNA) and active (rRNA) microbial communities. Among the four organismal group under investigation, the bacterial community was most affected by the main crop, and unweighted and weighted UniFrac analyses (explaining respectively 16.4% and 51.3% of the observed variation) pointed at a quantitative rather than a qualitative shift. LEfSe analyses were employed for each of the four organismal groups to taxonomically pinpoint the effects of soil management. Concentrating on the bacterial community in the pea rhizosphere, organic soil management resulted in a remarkable activation of members of the Burkholderiaceae, Enterobacteriaceae, and Pseudomonadaceae. Prolonged organic soil management was also accompanied by significantly higher densities of bacterivorous nematodes, whereas levels of M. chitwoodi had dropped drastically. Though present and active in the fields under investigation Orbiliaceae, a family harboring numerous nematophagous fungi, was not associated with the M. chitwoodi decline. A closer look revealed that a local accumulation and activation of Pseudomonas, a genus that includes a number of nematode-suppressive species, paralleled the lower M. chitwoodi densities. This study underlines the relevance of taking along both resident and active fractions of multiple organismal groups while mapping the impact of e.g. crops and soil management regimes.

This study aims to estimate sorghum supply elasticity in South Africa. The study used time series data spanning from 1998 to 2016, obtained from the abstracts of agricultural statistics. The Variance Error Correction Model was employed; the study used two dependent variables, these being area and yield response functions. The results have shown that the area response function was found to be a robust model as most of the variables were significant, responsive and elastic. Maize price, as a competing crop for sorghum, negatively influenced the area allocation; however, the remaining variableshad a positive impact on area allocation in the long-run. The yield response function was found not to be robust and hence not adopted. It was therefore concluded that the area response function is more robust than the yield response function, hence sorghum production has shown more response to areaallocation than yield. The findings further indicated that the error correction term for area and for the yield response function was –1.55 and –1.30, respectively. This indicated that the two models were able to revert to equilibrium. Based on the findings, the study recommends that amongst other methods to enhance sorghum output, producers could use improved varieties or hybrids, as this action would result in allocation of more land to sorghum production, following price change.

Conventional agricultural production systems, typified by large inputs of mineral fertilizers and pesticides, reduce soil biodiversity and may negatively affect ecosystem services such as carbon fixation, nutrient cycling and disease suppressiveness. Organic soil management is thought to contribute to a more diverse and stable soil food web, but data detailing this effect are sparse and fragmented. We set out to map both the resident (rDNA) and the active (rRNA) fractions of bacterial, fungal, protozoan and metazoan communities under various soil management regimes in two distinct soil types with barley as the main crop. Contrasts between resident and active communities explained 22%, 14%, 21% and 25% of the variance within the bacterial, fungal, protozoan, and metazoan communities. As the active fractions of organismal groups define the actual ecological functioning of soils, our findings underline the relevance of characterizing both resident and active pools. All four major organismal groups were affected by soil management (p

Asset-intensive organizations rely on physical assets that are expensive, complex, and have a significant impact on organizational performance. The management of such assets is essential when seeking for reliable performance in a world of increasing uncertainties. The observation that asset-intensive organizations deal with increasingly complex and tightly coupled systems and often operate in highly demanding environments may indicate that they should adopt practices from high reliability organizations (HRO) to ensure and maintain reliable performance in the fourth industrial revolution. This chapter operationalizes the HRO concept in the field of physical asset management, measures to what extent the underlying principles are recognized, and explores the relationship between the HRO principles and asset performance using a descriptive survey. Results indicated that the HRO principles are recognized and may, therefore, serve as an instrument for reliable performance when adopting new technologies. A positive relation between asset performance and the five HRO principles was identified.

DSO’s are increasingly expected and motivated to improve the environmental impact of their assets. A key improvement opportunity can be found in the procurement process, as most characteristics that determine an asset’s environmental impact are committed at this stage. Many DSO’s look to LCA as the international industry standard for assessing and quantifying environmental impact. Full LCA however, is too complex and tedious to be pragmatically used in procurement processes, as these require simplicity and accessibility to provide equal opportunity for all participants. By only including only the most dominant input & output parameters of a “master” LCA, the process of performing an LCA on a specific asset can be greatly simplified. This simplified model is demonstrated and evaluated through a case study on the procurement of medium voltage switchgear. The streamlined LCA approach presented in this article maintains most of the relevance of full LCA, while greatly reducing the complexity and resources required for its use.

This is BioMed Central's submission to the UK House of Commons Science and Technology Commission's Inquiry into scientific publications. The case is made that it is urgently needed that scientific research articles be made available with open access. The Government can help, particularly if the research is funded with public money. Questions posed by the Committee are answered in the document.

An analogy of the biblical loaves and fishes, and the limitless sharing of (scientific) information.