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Smith M Woodroffe A Smith R Holguin S Martinez J Filipek PA Modahl C Moore B Bocian ME Mays L Laulhere T Flodman P Spence MA 《Cytogenetic and genome research》2002,98(4):233-239
In a sporadic case of autism and language deficit due to auditory processing defects, molecular genetic studies revealed that a chromosomal deletion occurred in the 13q12-->q13 region. No chromosome abnormalities were detected in the parents. We determined that the deletion occurred on the paternally derived chromosome 13. There are two previous reports of chromosome 13 abnormalities in patients with autism. The deletion in the subject described in this paper maps between the two chromosome 13 linkage peaks described by Bradford et al. (2001) in studies of subjects with autism and language deficits. The 9-Mb region deleted in the patient described here contains at least four genes that are expressed in brain and that play a role in brain development. They are NBEA, MAB21L1, DCAMKL1 and MADH9. These genes therefore represent candidate genes for autism and specific language deficits. 相似文献
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The large delta antigen of hepatitis delta virus potently inhibits genomic but not antigenomic RNA synthesis: a mechanism enabling initiation of viral replication
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Hepatitis delta virus (HDV) contains two types of hepatitis delta antigens (HDAg) in the virion. The small form (S-HDAg) is required for HDV RNA replication, whereas the large form (L-HDAg) potently inhibits it by a dominant-negative inhibitory mechanism. The sequential appearance of these two forms in the infected cells regulates HDV RNA synthesis during the viral life cycle. However, the presence of almost equal amounts of S-HDAg and L-HDAg in the virion raised a puzzling question concerning how HDV can escape the inhibitory effects of L-HDAg and initiate RNA replication after infection. In this study, we examined the inhibitory effects of L-HDAg on the synthesis of various HDV RNA species. Using an HDV RNA-based transfection approach devoid of any artificial DNA intermediates, we showed that a small amount of L-HDAg is sufficient to inhibit HDV genomic RNA synthesis from the antigenomic RNA template. However, the synthesis of antigenomic RNA, including both the 1.7-kb HDV RNA and the 0.8-kb HDAg mRNA, from the genomic-sense RNA was surprisingly resistant to inhibition by L-HDAg. The synthesis of these RNAs was inhibited only when L-HDAg was in vast excess over S-HDAg. These results explain why HDV genomic RNA can initiate replication after infection even though the incoming viral genome is complexed with equal amounts of L-HDAg and S-HDAg. These results also suggest that the mechanisms of synthesis of genomic versus antigenomic RNA are different. This study thus resolves a puzzling question about the early events of the HDV life cycle. 相似文献
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Nyland Cecilia Askham Modahl Ingunn Saur Raadal Hanne Lerche Hanssen Ole Jørgen 《The International Journal of Life Cycle Assessment》2003,8(6):331-336
Aim, Scope and Background When materials are recycled they are made available for use for several future life cycles and can therefore replace virgin
material more than just once. In order to analyse the optimal waste management system for a given material, the authors have
analysed the material flows in a life cycle perspective. It is important to distinguish this approach for material flow analysis
for a given material from life cycle analysis of products. A product life cycle analysis analyses the product system from
cradle to grave, but uses some form of allocation in order to separate the life cycle of one product from another in cases
where component materials are recycled. This paper does not address allocation of burdens between different product systems,
but rather focuses on methodology for decision making for waste management systems where the optimal waste management system
for a given material is analysed. The focus here is the flow of the given material from cradle (raw material extraction) to
grave (the material, or its inherent energy, is no longer available for use). The limitation on the number of times materials
can be recycled is set by either the recycling rate, or the technical properties of the recycled material.
Main Features This article describes a mathematical geometric progression approach that can be used to expand the system boundaries and
allow for recycling a given number of times. Case studies for polyethylene and paperboard are used to illustrate the importance
of including these aspects when part of the Goal and Scope for the LCA study is to identify which waste management treatment
options are best for a given material. The results and discussion examine the different conclusions that can be reached about
which waste management option is most environmentally beneficial when the higher burdens and benefits of recycling several
times are taken into account.
Results In order to assess the complete picture of the burdens and benefits arising from recycling the system boundaries must be expanded
to allow for recycling many times. A mathematical geometric progression approach manages to take into account the higher burdens
and benefits arising from recycling several times. If one compares different waste management systems, e.g. energy recovery
with recycling, without expanding the system to include the complete effects of material recycling one can reach a different
conclusion about which waste management option is preferred.
Conclusions When the purpose of the study is to compare different waste management options, it is important that the system boundaries
are expanded in order to include several recycling loops where this is a physical reality. The equations given in this article
can be used to include these recycling loops. The error introduced by not expanding the system boundaries can be significant.
This error can be large enough to change the conclusions of a comparative study, such that material recycling followed by
incineration is a much better option than waste incineration directly.
Recommendations and Outlook When comparing waste management solutions, where material recycling is a feasible option, it is important to include the relevant
number of recycling loops to ensure that the benefits of material recycling are not underestimated. The methodology presented
in this article should be used in future comparative studies for strategic decision-making for waste management. The approach
should not be used for LCAs for product systems without due care, as this could lead to double counting of the benefits of
recycling (depending on the goal and scope of the analysis). For materials where the material cycle is more of a closed loop
and one cannot truly say that recycled materials replace virgin materials, a more sophisticated approach will be required,
taking into account the fact that recycled materials will only replace a certain proportion of virgin materials. 相似文献
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Aggressive dominance orders of all adults in a confined troop of Japanese macaques (Macaca fuscata) were determined each mating and birth season during a 4-year interval. Males outranked more females in the mating than in the birth season, and some males shifted back and forth from ranks lower than female ranks in the birth season to ranks higher than female ranks in the mating season. Mating behaviour (number of female partners in mount and ejaculation series and ejaculation frequency) did not differ among males with ranks higher than, as high as, or lower than those of most females, nor did individual males mate more in years, when they were high-ranking than in years when they were not. There was a correlation, however, between ejaculation frequency and the number of females defeated by males. A pattern of increasing male rank with age was found. 相似文献
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Testing environmental and social indicators for biorefineries: bioethanol and biochemical production
Clara Valente Andreas Brekke Ingunn Saur Modahl 《The International Journal of Life Cycle Assessment》2018,23(3):581-596
Purpose
The article aims to test indicators for assessing the environmental and social impacts of biorefineries. Testing environmental and social impact categories and indicators, and selecting the most suitable ones, will simultaneously contribute to the further development of social life cycle assessment (S-LCA) methodologies while assessing several dimensions of sustainability at biorefineries.Methods
The work applies two methodologies, environmental LCA (E-LCA) and social LCA (S-LCA), to two hypothetical production processes of second-generation bioethanol and biochemical in two alternative locations (Norway and the USA). Five impact categories were chosen for the E-LCA. The S-LCA was performed in two stages: a generic assessment (top-down approach) using the social hotspot database (SHDB 2013) to screen for potential social issues in the stakeholder group Worker in Norway and the USA and a specific assessment (bottom-up approach) for collecting data and confirming or refuting the SHDB results in the Norwegian case only.Results and discussion
Bioethanol produced in the Norwegian biorefinery would perform relatively well in relation to climate change targets, with emissions of approximately 11 g CO2-eq/MJ. The same production process located in the USA would produce emissions of approximately 29 g CO2-eq/MJ. Other biorefinery products are difficult to compare because of a lack of clear alternatives. Bioethanol and biochemicals produced in the hypothetical USA production process have higher burdens than those from the Norwegian production process in all environmental categories assessed. For both production processes, the main social risks were in the category Health and safety followed by Labor rights and decent work. More detailed investigations in an existing Norwegian biorefinery value chain confirmed some of the risk issues but discarded others, demonstrating the necessity of providing specific data and results for the social dimension.Conclusions
E-LCA and S-LCA make it possible to highlight the main environmental and social challenges when producing biochemicals. The SHDB has potential as a social screening tool although social indicators are not yet well established. Hence, specific assessment is necessary for validating the results in the social dimension. S-LCA is still in its infancy and needs to be applied in order to develop the best practice. The two methodologies addressed bioethanol and biochemical production performance in two different dimensions (environmental and social), and their combination makes it possible to achieve results that integrate the product-oriented approach with the more location-specific approach.10.
Ingunn Saur Modahl Cecilia Askham Kari-Anne Lyng Andreas Brekke 《The International Journal of Life Cycle Assessment》2012,17(7):932-943