500 research outputs found
Bacteriocin Activity of Lactic Acid Bacteria Isolated from Nunu, a Spontaneously Fermented Milk
According to literature, lactic acid bacteria have been used for ages as a natural preservative for dairy products as well as protective cultures.This is mainly due to their production of antimicrobial substances like organic acids and bacteriocins and their ability to compete against pathogenic and spoilage bacteria for nutrients. Nunu is a fermented dairy product enjoyed by the people of West Africa. This work was carried out for the purpose of identifying the antagonistic effects of bacteriocins of four lactic acid bacteria namely Lb. fermentum, Lb, plantarum, Lb. mesenteroides and W. confusa against some pathogenic/spoilage organisms which include Strep. faecalis, Sal. typhimirum, E. coli ATTC 24522, B. cereus and P. aeruginosa. Each of the LAB has different strains isolated at different times during the fermentation process.The activity shown by the bacteriocin against Gram negative bacteria is an unusual phenomenon and defies the observations of Klaenhammer, (1988) that bacteriocins are proteins which show inhibitory activity against closely related organisms. However, in this study, the bacteriocins of LAB strains were effective against Gram negative bacteria including E. coli ATCC 24522, P. aeruginosa and Sal. typhimirum. This was even to the extent that the highest antagonistic effect, 15.5 mm, was exhibited by P. aeruginosa against Lb. mesenteroides 6-7, though some the bacteriocins showed some antagonistic effects against the Gram positive bacteria with the highest being 14.5 mm shown by Lb. mesenteroides 0-23 against Strep. faecalis. B. cereus being another Gram positive bacterium was inhibited by only the bacteriocins of W. confusa 24-17.The present findings was supported by the observations made earlier by Mandal et al., (2008). According to the present study, starter cultures for nunu production can be made from Lb. mesenteroides 6-7 and W. confusa 24-17 and the fermentation allowed to take place within 48 hours
Genetic basis of human disorders of gonadal development
South Africa is unique in the arena of Intersex, in that for unknown reasons we have a very high percentage of ovotesticular DSD (True Hermaphrodite). Whereas ovotesticular DSD is the least common cause of hermaphroditism in other parts of the world, it is the most common cause of hermaphroditism in South Africa. There have been several studies in the past to determine the cause of ovotesticular DSD in our population but none of these studies found appropriate answers. The current state of understanding implicates signaling and signal transduction molecules and transcription factors suggesting that it is likely not all of the genetic factors involved have already been identified. It was hypothesized that exome sequencing of individuals with DGDs will identify new mutations and genes for these conditions. Therefore, this study aims to identify additional genes that are associated with ovotesticular DSD. By using a whole-genome sequencing approach we expected to be able to identify rare variants with this condition and determine the prevalence of mutations in these genes in the ovotesticular DSD population. After obtaining informed consent, blood specimen was obtained from eleven out of fifteen patients who had histological diagnosis of Ovotesticular DSD at the Red Cross War Memorial Hospital over a 10 year period. Blood specimen was also obtained from the biological parents of these children and sent to the Ostrer laboratory for whole genome sequencing and analysis. At the Ostrer laboratory, high quality DNA was extracted from blood for all of subjects and lymphoblastoid cell lines were created. Following sample preparation using the Illumina library preparation kit, sequencing was accomplished using paired-end sequencing technology on an Illumina HiSeq2000 sequencer. The data from the Illumina sequencers was analyzed first using the Illumina sequencing data analysis pipeline for quality control. Paired end reads were aligned to the Human Reference Genome (NCBI Build 36) using the BWA software. Each alignment was assigned a mapping quality score by BWA, which is the Phredscaled probability that a read is misaligned. The basic functional annotation of SNPs/Indels is performed by ANNOVAR. The clinical features of these patients was consistent with those found by other studies on Ovotesticular DSD in South Africa and it also showed the same pattern of variation to the clinical features of Ovotesticular DSD from other parts of the world. Similar to previous South African studies, this study found no convincing gene mutations as the possible etiology of Ovotesticular DSD in South Africa. Whiles gene mutations such as duplication of SOX 9 have been found in patients with XX Ovotesticular DSD from outside South Africa, this study could not identify any such mutations. This further adds to the suspicion that the unique features of Ovotesticular DSD in South Africa suggests a different etiology from that of other parts of the world. In conclusion, the etiology of Ovotesticular DSD in South Africa still remains elusive. It is however possible that a genetic mutation may be found from a more critical analysis of the genome of the patients and their parents
An approach for determining the extent of contribution of construction project features to accident causation
In the pursuit of Health and Safety (H&S) improvement within the UK construction industry, several studies have been conducted to identify accident causal factors to enable the development of accident prevention measures. Adding to such studies, a critique of H&S literature demonstrates that construction project features (CPFs) such as the nature of project, method of construction, site restriction, project duration, procurement system, design complexity, level of construction, and subcontracting contribute to accident causation and that their contribution is through the introduction of proximal accident causal factors into the construction process. However, the extent of this contribution by these CPFs remains sparingly known and requires further investigation. The study provides this insight by indicating that the extent to which CPFs contribute to accident causation is influenced by two factors; the extent to which the proximal factors contribute to accident causation; and the extent to which the proximal factors are prevalent within the CPFs. In line with this fresh insight, an approach for determining the extent to which CPFs contribute to accident causation is put forth. The approach proposes to use a qualitative–quantitative rating scale to determine the two determinant factors and then combine them using a mathematical formula to obtain the extent to which CPFs contribute to accident causation. By this approach the grey areas in literature concerning the extent to which CPFs contribute to accident causation will be illuminated and by that contribute to improvement in construction accident prevention
The health and safety impact of construction project features
Purpose – Despite the established significance of underlying accident causes to health and safety (H&S), and the persistent reporting of the underlying accident causal influence of construction project features (CPFs) which emanate from pre-construction decisions, no empirical research has focused on CPFs in terms of assessing their degree of potential to influence accident occurrence. The purpose of this paper is to, therefore, investigate this facet of the accident causal influence of CPFs. Design/methodology/approach – A mixed method design was used involving semi-structured interviews, and a questionnaire survey of UK construction professionals. Findings – CPFs generally have a moderate or a high potential to influence accident occurrence, implying a fair or severe potential to cause harm in terms of the H&S of workers. The degree of potential of CPFs to influence accident occurrence is influenced by: the extent to which certain proximate causes of accidents are common/prevalent within CPFs;and the degree of potential of those proximate causes to influence accident occurrence. Originality/value – These findings provide insight into the H&S consequences of CPFs, awareness of which is essential if pre-construction project participants are to implement appropriate risk control measures especially in the early phases of projects to mitigate the accident causal influence of CPFs. The findings reinforce the contribution of clients and their design and project management teams to accident causation, the significance of the early planning of H&S in construction project delivery, and the importance of driving mechanisms such as the Construction (Design and Management) Regulations 2007
A comparison of third-generation semi-invasive arterial waveform analysis with thermodilution in patients undergoing coronary surgery
Uncalibrated semi-invasive continous monitoring of cardiac index (CI) has recently gained increasing interest. The aim of the present study was to compare the accuracy of CI determination based on arterial waveform analysis with transpulmonary thermodilution. Fifty patients scheduled for elective coronary surgery were studied after induction of anaesthesia and before and after cardiopulmonary bypass (CPB), respectively. Each patient was monitored with a central venous line, the PiCCO system, and the FloTrac/Vigileo-system. Measurements included CI derived by transpulmonary thermodilution and uncalibrated semi-invasive pulse contour analysis. Percentage changes of CI were calculated. There was a moderate, but significant correlation between pulse contour CI and thermodilution CI both before (r(2) = 0.72, P < 0.0001) and after (r(2) = 0.62, P < 0.0001) CPB, with a percentage error of 31% and 25%, respectively. Changes in pulse contour CI showed a significant correlation with changes in thermodilution CI both before (r(2) = 0.52, P < 0.0001) and after (r(2) = 0.67, P < 0.0001) CPB. Our findings demonstrated that uncalibrated semi-invasive monitoring system was able to reliably measure CI compared with transpulmonary thermodilution in patients undergoing elective coronary surgery. Furthermore, the semi-invasive monitoring device was able to track haemodynamic changes and trends
New tool will help civil engineers meet CDM requirements to design for safety
© ICE Publishing. All rights reserved. A new tool is being developed to help civil engineers and other construction professionals improve their capability to design for safety under the Construction (Design and Management) Regulations. Patrick Manu and Lamine Mahdjoubi of the University of the West of England, Alistair Gibb of Loughborough University and Michael Behm of East Carolina University report
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Country context-based opportunities for improving health and safety
Using Nigeria as a case study, this study examines the Social, Political, Economic, Cultural and Religious (SPECR) contexts of developing countries towards unearthing and discussing
the opportunities for improving Health and Safety (H&S). Previous research demonstrates the imperativeness of understanding the SPECR contexts of developing countries and the
implications of practices, policies and laws that are not underpinned or based on a good understanding of the contexts. However, this has received little attention and the contexts-based
opportunities for improving H&S remain unexamined. Through a critical review of literature, it was found that the contexts-based opportunities for improving H&S centre around social
media platforms, unexplored potentials and undeveloped fields, the quest of Nigerians to embrace change, religion which teaches morals, community leadership where the leaders are
able to command respect, the collectivist cultural dimension which emphasises affection, kinship and power relationship. While issues such as the sensitive nature of religion pose challenges, the study highlights SPECR characteristics, such as the collectivist cultural dimension, that policymakers and contractors should consider in developing policies and strategies towards improving H&S. Nevertheless, as the study is a theoretical piece of work,
further empirical evidence on the subject is recommended
CIRCULAR ECONOMY IN CONSTRUCTION: A SYSTEMATIC LITERATURE REVIEW OF THE APPLICATION OF MATERIAL PASSPORTS
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Critical Barriers to Prevention through Design in Construction in Nigeria: A Qualitative Inquiry
Purpose
Given the complexities in improving safety in the construction industry globally, which is exacerbated by the complex safety environment in developing countries (DCs), prevention through design (PtD) has been established to improve occupational safety and health (OSH) where applied. However, it has received very little attention in DCs and the extant literature with limitations. Using Nigeria as a case study, the current study advances the understanding of PtD in DCs by investigating the critical barriers to PtD and other potential OSH responsibilities of designers in the construction industry.
Design/methodology/approach
Twenty-eight semi-structured interviews and e-interviews of architects, builders and civil engineers in Nigeria were analysed using the six-phase thematic analysis. To improve the trustworthiness of the research, triangulation, peer-debriefing, refining the interview protocol and thick detailed description were done.
Findings
The study's findings question the extant general knowledge and understanding of PtD among clients and designers and its technical aspect among designers where it is skewed to structural safety and omitted in universities' curricula. This explains the inconclusive findings of existing studies on why there is a high level of awareness of PtD but a low level of implementation. There is little client support for PtD, and designers have limited influence on clients in terms of it. The fear of liability from PtD is exacerbated by the limited legal system and lack of adequate legislation in the country. The demotivating attitudes of clients and contractors towards designers in terms of PtD are also reported, just as there are project delivery barriers such as traditional procurement not supporting PtD as design and build procurement does.
Social implications
For the sustainable growth in the practice of PtD, the increased and improved quality of education and awareness of PtD is needed but this must focus on instilling a robust understanding of it among designers based on the local context. This educational requirement can be supported by statute.
Originality/value
Through qualitative data, the findings explain and offer insight into the inconclusive findings in the extant studies on PtD in Nigeria. Also, it contributes to improving health and safety by advancing the understanding of the critical barriers to PtD and other potential OSH responsibilities of designers in D Nigeria's construction using qualitative data
Addressing challenges to building information modelling implementation in UK: Designers' perspectives
Building information modelling (BIM) has been proposed as a technology-enabled process for more efficient and effective management of information in digital and virtual environments. Many challenges, however, exist and undermine its effective implementation within the construction industry. The identification of these challenges is critical to the successful implementation and adoption of BIM, especially in view of many implementation risks. Despite the critical role of the design phase to project delivery and BIM usage, few studies have sought to interrogate the challenges faced by designers and the solutions that are being applied to address them. To address this gap, this study aimed to identify and classify challenges faced by designers with particular focus on proposed solutions for alleviating the identified challenges. Through a qualitative research strategy, semi-structured interviews were used to solicit perspectives of UK design professionals on design profession-specific BIM implementation challenges and solutions. Findings reveal that challenges are mostly organisational and external environmental issues with rather cursory allusion to technological challenges which are widely reported in the literature. The solutions identified for alleviating designers’ BIM implementation challenges include earlier input and integration from whole supply chain as well as more support institutional support and facilitation. The promotion of open-BIM standards, tailored insurance as well as principal supplier leadership were also proposed as viable solutions to BIM implementation challenges. Variations in the challenges and proposed solutions appear to differ across different categories of firms investigated in this study, particularly in relation to the cost of implementation
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