182 research outputs found
A generic model of dyadic social relationships
We introduce a model of dyadic social interactions and establish its
correspondence with relational models theory (RMT), a theory of human social
relationships. RMT posits four elementary models of relationships governing
human interactions, singly or in combination: Communal Sharing, Authority
Ranking, Equality Matching, and Market Pricing. To these are added the limiting
cases of asocial and null interactions, whereby people do not coordinate with
reference to any shared principle. Our model is rooted in the observation that
each individual in a dyadic interaction can do either the same thing as the
other individual, a different thing or nothing at all. To represent these three
possibilities, we consider two individuals that can each act in one out of
three ways toward the other: perform a social action X or Y, or alternatively
do nothing. We demonstrate that the relationships generated by this model
aggregate into six exhaustive and disjoint categories. We propose that four of
these categories match the four relational models, while the remaining two
correspond to the asocial and null interactions defined in RMT. We generalize
our results to the presence of N social actions. We infer that the four
relational models form an exhaustive set of all possible dyadic relationships
based on social coordination. Hence, we contribute to RMT by offering an answer
to the question of why there could exist just four relational models. In
addition, we discuss how to use our representation to analyze data sets of
dyadic social interactions, and how social actions may be valued and matched by
the agents
Eco-Bat: A design tool for assessing environmental impacts of buildings and equipment
This paper presents the features of Eco-Bat, a computer program developed to assess the environmental impacts of buildings, including construction materials and energy consumed, during its life cycle. The methodology used to evaluate environmental impacts based on a life cycle assessment (LCA) approach, compatible with ISO 14040 standards, is detailed. The data are mainly extracted from an environmental impacts database, Ecoinvent, which contains values for the manufacturing and elimination of numerous materials as well as other processes. Two applications are presented to illustrate the possibilities offered by Eco-Bat. The first one is a comparison of different variants of building facades. The second example shows the analysis of a whole building including its energy consumptio
Energy saving potentials in historic buildings’ renovations ::to which extent is the heating demand limit value (SIA 380/1) reachable and at which costs?
The renovation of historic buildings is essential to meet the Swiss objectives for energy consumption in 2050. These buildings offer a great saving potential, however, the heritage preservation has to be considered in the renovation scenarios. While essential for the historic conservation, this consideration restricts the renovation possibilities to achieve the heating demand requirements according to the SIA 380/1 standard. This study introduces a framework for identifying the suitable historic buildings’ renovation schemes considering life cycle costs, energy and life cycle environmental impacts. With a case study, the feasibility of achieving the energy performance SIA 380/1 standard is then discussed
A novel bioinformatics pipeline to discover genes related to arbuscular mycorrhizal symbiosis based on their evolutionary conservation pattern among higher plants
Genes involved in arbuscular mycorrhizal (AM) symbiosis have been identified primarily by mutant screens, followed by identification of the mutated genes (forward genetics). In addition, a number of AM-related genes has been identified by their AM-related expression patterns, and their function has subsequently been elucidated by knock-down or knock-out approaches (reverse genetics). However, genes that are members of functionally redundant gene families, or genes that have a vital function and therefore result in lethal mutant phenotypes, are difficult to identify. If such genes are constitutively expressed and therefore escape differential expression analyses, they remain elusive. The goal of this study was to systematically search for AM-related genes with a bioinformatics strategy that is insensitive to these problems. The central element of our approach is based on the fact that many AM-related genes are conserved only among AM-competent species.Results: Our approach involves genome-wide comparisons at the proteome level of AM-competent host species with non-mycorrhizal species. Using a clustering method we first established orthologous/paralogous relationships and subsequently identified protein clusters that contain members only of the AM-competent species. Proteins of these clusters were then analyzed in an extended set of 16 plant species and ranked based on their relatedness among AM-competent monocot and dicot species, relative to non-mycorrhizal species. In addition, we combined the information on the protein-coding sequence with gene expression data and with promoter analysis. As a result we present a list of yet uncharacterized proteins that show a strongly AM-related pattern of sequence conservation, indicating that the respective genes may have been under selection for a function in AM. Among the top candidates are three genes that encode a small family of similar receptor-like kinases that are related to the S-locus receptor kinases involved in sporophytic self-incompatibility.Conclusions: We present a new systematic strategy of gene discovery based on conservation of the protein-coding sequence that complements classical forward and reverse genetics. This strategy can be applied to diverse other biological phenomena if species with established genome sequences fall into distinguished groups that differ in a defined functional trait of interest
Morphological and immunocytochemical analysis of Escherichia coli -specific surface antigens in wildtype strains and in recombinant Vibrio cholerae
Adhesion is the first step in the pathogenesis of enterotoxigenic Escherichia coli infections. The genes encoding the most prevalent adhesion factors CFA/I, CS3 and CS6 were cloned into Vibrio cholerae strain CVD 103-HgR and expression of fimbriae was investigated in wildtype and recombinant strains by transmission electron microscopy in conjunction with immunolabelling and negative staining. Negative staining was effective in revealing CFA/I and CS3, but not CS6. Although morphology of fimbriae differed between wildtype and recombinant strains, corresponding surface antigens were recognized by specific antibodies. The present study provides evidence that ETEC-specific fimbriae can adequately be expressed in an attenuated V. cholerae vaccine strain and that immunoelectron microscopy is a critical tool to validate the surface expression of antigens in view of their possible suitability for recombinant vaccine
Methodology for cost-effective energy and carbon emissions optimization in building renovation (Annex 56): methodology and assessment of renovation measures by parametric calculations
Buildings are responsible for a major share of energy use and have accordingly been a special target in the global actions for climate change mitigation, with measures that aim at improving their energy efficiency, reduce carbon emissions and increase renewable energy use.
IEA-EBC project «Cost-Effective Energy and Carbon Emissions Optimization in Building Renovation» intends to develop a calculation basis for future standards, which aim at maximum effects on reducing carbon emissions and primary energy use. Thereby, the project pays special attention to the renovation of existing residential buildings and to cost effective building renovatio
Methodology for cost-effective energy and carbon emissions optimization in building renovation (Annex 56)
"Energy in Buildings and Communities Programme, March 2017"Buildings are responsible for a major share of energy use and have been a special target in the global actions for climate change mitigation, with measures that aim at improving their energy efficiency, reduce carbon emissions and increase renewable energy use. The IEA-EBC Annex 56 project «Cost-Effective Energy and Carbon Emissions Optimization in Building Renovation» intends to develop the basics for future standards, which aim at maximizing effects on reducing carbon emissions and primary energy use while taking into account the cost-effectiveness of related measures. The IEA EBC Annex 56 project pays special attention to cost effective energy related renovation of existing residential buildings and low-tech office buildings (without air conditioning systems).info:eu-repo/semantics/publishedVersio
Strong gender differences in reproductive success variance, and the times to the most recent common ancestors
The Time To the Most Recent Common Ancestor (TMRCA) based on human
mitochondrial DNA (mtDNA) is estimated to be twice that based on the
non-recombining part of the Y chromosome (NRY). These TMRCAs have special
demographic implications because mtDNA is transmitted only from mother to
child, and NRY from father to son. Therefore, mtDNA reflects female history,
and NRY, male history. To investigate what caused the two-to-one female-male
TMRCA ratio in humans, we develop a forward-looking agent-based model (ABM)
with overlapping generations and individual life cycles. We implement two main
mating systems: polygynandry and polygyny with different degrees in between. In
each mating system, the male population can be either homogeneous or
heterogeneous. In the latter case, some males are `alphas' and others are
`betas', which reflects the extent to which they are favored by female mates. A
heterogeneous male population implies a competition among males with the
purpose of signaling as alphas. The introduction of a heterogeneous male
population is found to reduce by a factor 2 the probability of finding equal
female and male TMRCAs and shifts the distribution of the TMRCA ratio to higher
values. We find that high male-male competition is necessary to reproduce a
TMRCA ratio of 2: less than half the males can be alphas and betas can have at
most half the fitness of alphas. In addition, in the modes that maximize the
probability of having a TMRCA ratio between 1.5 and 2.5, the present generation
has 1.4 times as many female as male ancestors. We also tested the effect of
sex-biased migration and sex-specific death rates and found that these are
unlikely to explain alone the sex-biased TMRCA ratio observed in humans. Our
results support the view that we are descended from males who were successful
in a highly competitive context, while females were facing a much smaller
female-female competition
The Leadership Processes of Pacific Public Servants in Aotearoa, New Zealand
This dissertation presents research focused on leadership processes among Pacific public servants at multiple levels in the New Zealand Public Service. The current study was guided by this research question: What are the leadership processes currently employed by Pacific public servants in the New Zealand Public Service? This study also explored participants' views on the effect of Pacific cultural backgrounds and organisational contexts on their current experience of leadership processes. The exploration of the topic was developed within a post-positivist research paradigm, using phenomenological methodology to examine the leadership processes of Pacific public servants. It employs qualitative case studies of two New Zealand Public Service organisations in the Wellington region. I employed two data collection tools in these case studies. The first was the use of in-depth interviews, and the second was an analysis of relevant organisational documents. A total of sixteen Pacific public servants participated in my study, eight from each case organisation. The findings indicated that the Pacific participants understood leadership as a social process of collective influence within a context. Participants perceived participating, networking and relationship building, learning about leadership from cultural contexts, and practising the Pacific value of va as important leadership processes for their performance in the organisations in which they were working. This study also found that the organisations' key roles and leadership values, which are embedded in Pacific cultures, shaped participants' experiences of the leadership processes. The findings also highlight some factors that contribute to and constrain the Pacific public servants' leadership processes. This emphasises the need for diverse policies to encompass leadership development. This study also highlights the need for leadership support for Pacific public servants at all levels in their New Zealand organisations. Practical and future research recommendations gained from the findings are discussed. The study contributes to the field of leadership research on Pacific public servants in New Zealand, and provides a different perspective on leadership processes in general leadership theory
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