17 research outputs found

    Identifying the attributes of a profession in the practice and regulation of fire safety engineering

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    Fire Safety Engineering is often implemented within a framework that requires a recognized and recognizable profession. This article reviews the current state of various attributes that define Fire Safety Engineering as a profession. It is argued that: 1) reliance on prescriptive solutions opens the domain to practitioners that do not possess the required specialist knowledge; 2) the fire safety engineering process is often triggered through non-compliances to individual prescriptive provisions, negatively impacting on the discipline's professional authority; 3) the discipline operates in a manner that exposes it to challenges of its ethical code; and 4), the lack of a well-defined accreditation framework challenges the professional culture. The resulting environment favours a customer relationship between those commissioning the work and the Fire Safety Engineer, rather than the client relationship necessary for professional practise. Most engineering disciplines respond to failures by formalisation of the profession around its duty of care to society. Conversely, in Fire Safety Engineering such responses have focused on regulation. Recent incidents are a significant impetus and opportunity for the fire safety profession to better formalize itself

    Combining Ability For Earliness And Yield Among South Sudanese F1 Sorghum Genotypes

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    The development of staygreen genotypes through hybridization is an important food security strategy in the semi-arid tropics. This study used 36 sorghum synthetics obtained from a 6 x 6 full diallel mating design. The parents, F1 progenies and their reciprocals showed significant difference for days to flowering suggesting their diversity with regard to this triat. There were significant differences among the maternal and non-maternal effects implying that maternal genes play a greater role in regulating maturity. There were higher genetic predictability ratios for days to flowering, panicle weight and grain weight, suggesting that additive gene action played a bigger role than non-additive genes in the control of these traits. The study identified parental lines, ICSV III IN, B5 and Macia as exhibiting earliness that can be exploited in the breeding program for drought evading hybrids. Similarly, the F1 crosses B35 x Okabir, Lodoka x B35, Okabir x Macia, ICSV II IN x Macia, ICSV III IN x Akuorachot, Lodoka x Akuorachot and Lodoka x Okabir were identified as drought evading synthetics while F1 crosses, B35 x Akuorachot, B35 x Macia, Lodoka x B35, ICSV III IN x Macia, and Lodoka x Macia were identified as high yielding synthetics

    Morphological peculiarites and functional activity of adipose-derived mesenchimal stem cells during in vitro cultivation conditions

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    The studies were conducted on 2-3-months-old males of C57BL/6 mice weighing 20–24 g. Obtaining and cultivating of adipose-derived mesenchimal stem cells (AD MSCs) were carried out in a sterile laminar box with compliance of conditions of asepsis and antiseptics. AD MSCs of the 2, 4, 7 and 12 passages were analyzed. Morphometric analysis was performed using a light microscopy. Morphometric parameters such as cell and nucleus area or nuclear-cytoplasmic ratio (NCR) were calculated using the Axiovision light microscope (Carl Zeiss, Germany) and ImageJ 1.45 software. Trypan blue dye used for investigation of the viability of MSC. The morphological characteristics of mesenchymal stem cells from adipose tissue during the process of cultivation changes: at the first passages of cultivation, the cells are spindle-shaped with two, at least three, long long cytoplasmic processes, located bipolar. Near the nucleus the Golgi complex is clearly visible – a sign of active cells. At later passages cells have a small cytoplasmic processes and the bipolar arrangement of processes changes by stellar arrangement. Golgi complex is also clearly visualized. The indicator of the nuclear-cytoplasmic ratio in MSC from adipose tissue is significantly reduced at 7 passage to 0.2189 ± 0.0122 (P < 0.01), and at 12 passage to 0.1111 ± 0.0086 (P < 0.001) compared to the 2 passage. The coefficient of proliferation of MSC from adipose tissue is significantly reduced at 12th passage. The viability of mesenchymal stem cells from adipose tissue with an increasing of a number of passages significantly reduces and at the 12th passage of cultivation reaches 84,67 ± 1,36* (P < 0.05). The content of apoptotic cells that exhibited sensitivity to serum-free significantly increased at 7 and 12 passages and was respectively 21.33 ± 1.36 (P < 0.05) and 23.67 ± 0.97% (P < 0.05)

    The innovation of the symbiosome has enhanced the evolutionary stability of nitrogen fixation in legumes

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    Nitrogen-fixing symbiosis is globally important in ecosystem functioning and agriculture, yet the evolutionary history of nodulation remains the focus of considerable debate. Recent evidence suggesting a single origin of nodulation followed by massive parallel evolutionary losses raises questions about why a few lineages in the N2-fixing clade retained nodulation and diversified as stable nodulators, while most did not. Within legumes, nodulation is restricted to the two most diverse subfamilies, Papilionoideae and Caesalpinioideae, which show stable retention of nodulation across their core clades. We characterize two nodule anatomy types across 128 species in 56 of the 152 genera of the legume subfamily Caesalpinioideae: fixation thread nodules (FTs), where nitrogen-fixing bacteroids are retained within the apoplast in modified infection threads, and symbiosomes, where rhizobia are symplastically internalized in the host cell cytoplasm within membrane-bound symbiosomes (SYMs). Using a robust phylogenomic tree based on 997 genes from 147 Caesalpinioideae genera, we show that losses of nodulation are more prevalent in lineages with FTs than those with SYMs. We propose that evolution of the symbiosome allows for a more intimate and enduring symbiosis through tighter compartmentalization of their rhizobial microsymbionts, resulting in greater evolutionary stability of nodulation across this species-rich pantropical legume clade

    The innovation of the symbiosome has enhanced the evolutionary stability of nitrogen fixation in legumes

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    Nitrogen-fixing symbiosis is globally important in ecosystem functioning and agriculture, yet the evolutionary history of nodulation remains the focus of considerable debate. Recent evidence suggesting a single origin of nodulation followed by massive parallel evolutionary losses raises questions about why a few lineages in the N2 -fixing clade retained nodulation and diversified as stable nodulators, while most did not. Within legumes, nodulation is restricted to the two most diverse subfamilies, Papilionoideae and Caesalpinioideae, which show stable retention of nodulation across their core clades. We characterize two nodule anatomy types across 128 species in 56 of the 152 genera of the legume subfamily Caesalpinioideae: fixation thread nodules (FTs), where nitrogen-fixing bacteroids are retained within the apoplast in modified infection threads, and symbiosomes, where rhizobia are symplastically internalized in the host cell cytoplasm within membrane-bound symbiosomes (SYMs). Using a robust phylogenomic tree based on 997 genes from 147 Caesalpinioideae genera, we show that losses of nodulation are more prevalent in lineages with FTs than those with SYMs. We propose that evolution of the symbiosome allows for a more intimate and enduring symbiosis through tighter compartmentalization of their rhizobial microsymbionts, resulting in greater evolutionary stability of nodulation across this species-rich pantropical legume clade

    A competency framework for fire safety engineering

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    Fire safety engineering accreditation and licensing is a subject of much debate in many jurisdictions especially following the Grenfell Tower fire and as a result of the many issues that have been brought to light following similar cladding related fires around the world. It is argued elsewhere that the lack of a well defined accreditation and licensing framework is one of the most significant weaknesses in the provision of fire safety engineering services in some jurisdictions; and in other jurisdictions where these frameworks do exist, they lack a well articulated definition of competency that fully reflects the expectations of those seeking to enter the profession. This paper discusses the motivation for stronger accreditation of fire safety engineers. Describing an idealised accreditation system, the unique role of the fire safety engineer is then discussed as is the need to redefine competency expectations to reflect the current needs of the public who the profession serves. Finally, a proposed competency framework is detailed. This links technical competencies to the skill in their application to complex engineering problems – namely the design of a fire safety strategy, and also highlights additional non-technical competencies which should be expected of those seeking to enter the profession

    The innovation of the symbiosome has enhanced the evolutionary stability of nitrogen fixation in legumes

    Get PDF
    Nitrogen‐fixing symbiosis is globally important in ecosystem functioning and agriculture, yet the evolutionary history of nodulation remains the focus of considerable debate. Recent evidence suggesting a single origin of nodulation followed by massive parallel evolutionary losses raises questions about why a few lineages in the N(2)‐fixing clade retained nodulation and diversified as stable nodulators, while most did not. Within legumes, nodulation is restricted to the two most diverse subfamilies, Papilionoideae and Caesalpinioideae, which show stable retention of nodulation across their core clades. We characterize two nodule anatomy types across 128 species in 56 of the 152 genera of the legume subfamily Caesalpinioideae: fixation thread nodules (FTs), where nitrogen‐fixing bacteroids are retained within the apoplast in modified infection threads, and symbiosomes, where rhizobia are symplastically internalized in the host cell cytoplasm within membrane‐bound symbiosomes (SYMs). Using a robust phylogenomic tree based on 997 genes from 147 Caesalpinioideae genera, we show that losses of nodulation are more prevalent in lineages with FTs than those with SYMs. We propose that evolution of the symbiosome allows for a more intimate and enduring symbiosis through tighter compartmentalization of their rhizobial microsymbionts, resulting in greater evolutionary stability of nodulation across this species‐rich pantropical legume clade
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