74,634 research outputs found
Influence of cell surface characteristics on adhesion of Saccharomyces cerevisiae to the biomaterial hydroxylapatite
The influence of the physicochemical properties of biomaterials on microbial cell adhesion is well known, with the extent of adhesion depending on hydrophobicity, surface charge, specific functional groups and acid–base properties. Regarding yeasts, the effect of cell surfaces is often overlooked, despite the fact that generalisations may not be made between closely related strains. The current investigation compared adhesion of three industrially relevant strains of Saccharomyces cerevisiae (M-type, NCYC 1681 and ALY, strains used in production of Scotch whisky, ale and lager, respectively) to the biomaterial hydroxylapatite (HAP). Adhesion of the whisky yeast was greatest, followed by the ale strain, while adhesion of the lager strain was approximately 10-times less. According to microbial adhesion to solvents (MATS) analysis, the ale strain was hydrophobic while the whisky and lager strains were moderately hydrophilic. This contrasted with analyses of water contact angles where all strains were characterised as hydrophilic. All yeast strains were electron donating, with low electron accepting potential, as indicated by both surface energy and MATS analysis. Overall, there was a linear correlation between adhesion to HAP and the overall surface free energy of the yeasts. This is the first time that the relationship between yeast cell surface energy and adherence to a biomaterial has been described
Recommended from our members
Facilitating a ‘non-judgmental’ skills-based co-design environment
This paper reflects on a pilot study for the design of a series of e-textiles workshops developed for the Nottinghamshire Mind Network community of mental health and wellbeing service users, managers and volunteers. The final workshops will form part of ‘An Internet of Soft Things’ (IoSofT) project, which seeks to develop a Person-Centred Approach (PCA) to design. The workshops should be experienced by participants as a non-judgemental environment, as one of the conditions of the Person-Centred Approach – unconditional positive regard (UPR) (Rogers, 1957). While the research team agree in theory that participants should feel safe and supported, putting non-judgement into practice in a multi - disciplinary environment, in which skills form the basis of workshop activity, has proved to be challenging. The paper introduces the key criteria of the PCA in psychotherapy, and describes the particular challenges that being non-judgemental presented to the textile designers and therapeutic practitioners who designed and facilitated the workshops. It presents an analysis of the design artefacts produced in the course of six workshop sessions (such as the ‘group agreement’), and participant feedback, and discusses the resulting framework that will be applied in the next iteration of workshops to enable participants’ comfort, creativity and autonomy
The effects on health of a publicly funded domestic heating programme: a prospective controlled study
<b>Objective</b>: To assess the effect of a publicly funded domestic heating programme on self-reported health.
<b>Design, setting and participants</b>: A prospective controlled study of 1281 households in Scotland receiving new central heating under a publicly funded initiative, and 1084 comparison households not receiving new heating. The main outcome measures were self-reported diagnosis of asthma, bronchitis, eczema, nasal allergy, heart disease, circulatory problems or high blood pressure; number of primary care encounters and hospital contacts in the past year; and SF-36 Health Survey scores.
<b>Results</b>: Usable data were obtained from 61.4% of 3849 respondents originally recruited. Heating recipients reported higher scores on the SF-36 Physical Functioning scale (difference 2.51; 95% CI 0.67 to 4.37) and General Health scale (difference 2.57; 95% CI 0.90 to 4.34). They were less likely to report having received a first diagnosis of heart disease (OR 0.69; 95% CI 0.52 to 0.91) or high blood pressure (OR 0.77; 95% CI 0.61 to 0.97), but the groups did not differ significantly in use of primary care or hospital services.
<b>Conclusions</b>: Provision of central heating was associated with significant positive effects on general health and physical functioning; however, effect sizes were small. Evidence of a reduced risk of first diagnosis with heart disease or high blood pressure must be interpreted with caution, due to the self-reported nature of the outcomes, the limited time period and the failure to detect any difference in health service use
Thermoluminescence of Antarctic meteorites: A rapid screening technique for terrestrial age estimation, pairing studies and identification of specimens with unusual prefall histories
Thermoluminescence (TL) is a promising technique for rapid screening of the large numbers of Antarctic meteorites, permitting identification of interesting specimens that can then be studied in detail by other, more definite techniques. Specifically, TL permits determination of rough terrestrial age, identification of potential paired groups and location of specimens with unusual pre-fall histories. Meteorites with long terrestrial ages are particularly valuable for studying transport and weathering mechanisms. Pairing studies are possible because TL variations among meteorites are large compared to variations within individual objects, especially for natural TL. Available TL data for several L3 fragments, three of which were paired by other techniques, are presented as an example of the use of TL parameters in pairing studies. Additional TL measurements, specifically a blind test, are recommended to satisfactorily establish the reliability of this pairing property. The TL measurements also identify fragments with unusual pre-fall histories, such an near-Sun orbits
Recommended from our members
Achieving abstraction: Generating far analogies promotes relational reasoning in children.
Analogical reasoning is essential for transfer by supporting recognition of relational similarity. However, not all analogies are created equal. The source and target can be similar (near), or quite different (far). Previous research suggests that close comparisons facilitate children's relational abstraction. On the other hand, evidence from adults indicates that the process of solving far analogies may be a more effective scaffold for transfer of a relational strategy. We explore whether engaging with far analogies similarly induces such a strategy in preschoolers. Children were provided with the opportunity to solve either a near or far spatial analogy using a pair of puzzle boxes that varied in perceptual similarity (Experiment 1), or to participate in a control task (Experiment 2). All groups were then presented with an ambiguous spatial reasoning task featuring both object and relational matches. We were interested in the relationship between near and far conditions and two effects: (a) children's tendency to spontaneously draw an analogy when solving the initial puzzle, and (b) their tendency to privilege relational matches over object matches in a subsequent, ambiguous task. Although children were more likely to spontaneously draw an analogy in the near condition, those who attempted the far analogy were more likely to privilege a relational match on the subsequent task. We argue that the process of solving a far analogy-regardless of a learner's spontaneous success in identifying the relation-contextualizes an otherwise ambiguous learning problem, making it easier for children to access and apply relational hypotheses. (PsycINFO Database Recor
The Population Biology and Transmission Dynamics of Loa loa
Endemic to Central Africa, loiasis – or African eye worm (caused by the filarial nematode Loa loa) – affects more than 10 million people. Despite causing ocular and systemic symptoms, it has typically been considered a benign condition, only of public health relevance because it impedes mass drug administration-based interventions against onchocerciasis and lymphatic filariasis in co-endemic areas. Recent research has challenged this conception, demonstrating excess mortality associated with high levels of infection, implying that loiasis warrants attention as an intrinsic public health problem. This review summarises available information on the key parasitological, entomological, and epidemiological characteristics of the infection and argues for the mobilisation of resources to control the disease, and the development of a mathematical transmission model to guide deployment of interventions
- …