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81.
Marzia Traverso Lynn Bell Peter Saling João Fontes 《The International Journal of Life Cycle Assessment》2018,23(3):597-606
Purpose
The main goal of this paper is to present the feasibility of the quantitative method presented in the Product Social Impact Assessment (PSIA) handbook throughout a case study. The case study was developed to assess the social impacts of a tire throughout its entire life cycle. We carried out this case study in the context of the Roundtable for the Product Social Metrics project in which 13 companies develop two methodologies, a qualitative and a quantitative one, for assessing the social impact of product life cycle.Methods
The quantitative methodology implemented for assessing the social impact of a Run On Flat tire mounted in a BMW 3 series consists of 26 indicators split in three groups. Each group represents a stakeholder group. Primary data of the quantitative indicators were collected along the product life cycle of the Run On Flat by involving the companies, which owned the main steps of the product life cycle. Throughout this case study, an ideal/worst-case scenario was defined for the distance-to-target approach to compare the social performances of more products when they are available.Results and discussion
The implementation of the PSIA quantitative method to a Run On Flat illustrated the necessity to have a referencing step in order to interpret the results. This is particularly important when the results are used to support decision-making process in which no experts are involved. It frequently happens in a big company where the management level has to take often decisions on different topics. Reference values were defined using ideal or worst-case-target scenarios (Fontes et al. 2014). For those topics where it was possible, an ideal/ethical scenario was defined, e.g., 0 h of child labor per product. In other cases, we defined a worst-case scenario, e.g., 0 training hours per product. It was then possible to interpret the results using a distance-to-target approach. A matrix was developed in the case study for identifying in which step of the product life cycle data is not available; that means we need more transparency in the supply chain.Conclusions
Each value of the matrix can be compared to the ideal/worst scenario to compare the step to each other and to identify along the product life cycle which step and the relative supplier that needs further measures to improve the product performance. Furthermore, a quantitative value for each indicator related to the product life cycle is calculated and compared with the ideal/worst scenario. The case study on Run On Flat represents the first implementation of the quantitative method of PSIA.82.
The rate of synonymous substitution in enterobacterial genes is inversely related to codon usage bias 总被引:31,自引:14,他引:31
Genes sequences from Escherichia coli, Salmonella typhimurium, and other
members of the Enterobacteriaceae show a negative correlation between the
degree of synonymous-codon usage bias and the rate of nucleotide
substitution at synonymous sites. In particular, very highly expressed
genes have very biased codon usage and accumulate synonymous substitutions
very slowly. In contrast, there is little correlation between the degree of
codon bias and the rate of protein evolution. It is concluded that both the
rate of synonymous substitution and the degree of codon usage bias largely
reflect the intensity of selection at the translational level. Because of
the high variability among genes in rates of synonymous substitution,
separate molecular clocks of synonymous substitution might be required for
different genes.
相似文献
83.
Chevonne D Eversley Tavia Clark Yuying Xie Jill Steigerwalt Timothy A Bell Fernando PM de Villena David W Threadgill 《BMC genetics》2010,11(1):1-6
Background
Sheep carcasses with yellow fat are sporadically observed at Norwegian slaughter houses. This phenomenon is known to be inherited as a recessive trait, and is caused by accumulation of carotenoids in adipose tissue. Two enzymes are known to be important in carotenoid degradation in mammals, and are therefore potential candidate genes for this trait. These are beta-carotene 15,15'-monooxygenase 1 (BCMO1) and the beta-carotene oxygenase 2 (BCO2).Results
In the present study the coding region of the BCMO1 and the BCO2 gene were sequenced in yellow fat individuals and compared to the corresponding sequences from control animals with white fat. In the yellow fat individuals a nonsense mutation was found in BCO2 nucleotide position 196 (c.196C>T), introducing a stop codon in amino acid position 66. The full length protein consists of 575 amino acids. In spite of a very low frequency of this mutation in the Norwegian AI-ram population, 16 out of 18 yellow fat lambs were found to be homozygous for this mutation.Conclusion
In the present study a nonsense mutation (c.196C>T) in the beta-carotene oxygenase 2 (BCO2) gene is found to strongly associate with the yellow fat phenotype in sheep. The existence of individuals lacking this mutation, but still demonstrating yellow fat, suggests that additional mutations may cause a similar phenotype in this population. The results demonstrate a quantitatively important role for BCO2 in carotenoid degradation, which might indicate a broad enzyme specificity for carotenoids. Animals homozygous for the mutation are not reported to suffer from any negative health or development traits, pointing towards a minor role of BCO2 in vitamin A formation. Genotyping AI rams for c.196C>T can now be actively used in selection against the yellow fat trait. 相似文献84.
NICO PM. SMIT WIETE WESTERHOF WILMA J. MENKO NETTY M. VERBEEK STAN PAVEL 《Pigment cell & melanoma research》1995,8(1):19-27
Melanocyte cultures were established and maintained routinely in Ham's F-10 medium containing 12-O-tetradecanoyl-phorbol-13-acetate (TPA), isobutylmethylxanthine (IBMX), cholera toxin (CT) and fetal calf serum (FCS). Three serum substitutes (Ultroser-G, Nutridoma-Hu and Nutricyte-H) were tested in order to obtain a medium without FCS having a more constant composition. Melanocyte proliferation was examined in long-term culture experiments by in situ cell counts at different periods of time. Only with Ultroser-G (1-2%) was the proliferation of melanocytes maintained without both FCS and CT, whereas the addition of the other two serum substitutes resulted in stabilization of melanocyte densities in the cultures up to 28 days. In the medium containing 1% Ultroser-G and IBMX without TPA minimal or no increases in melanocyte density were found. Addition of basic fibroblast growth factor (bFGF, 1 ng/ml) to the medium without TPA resulted in a partial restimulation of growth in different experiments. In this system with 1% Ultroser-G and 1 ng/ml bFGF, IBMX could also be replaced by other factors (dbcAMP LTC4 and a purified form of α-melanocyte stimulating hormone). The culture medium with 1% Ultroser-G containing TPA and IBMX is now used for routine melanocyte culture. In this medium TPN/IBMX can easily be replaced by bFGF/dbcAMP with optimal growth stimulation. The combination bFGF/α-MSH and other more physiological stimulators offers an alternative to study responses of melanocytes in culture with respect to proliferation, metabolism, and phenotype. 相似文献
85.
Salima FE van Weely J Christiaan van Denderen Martijn PM Steultjens Marike van der Leeden Michael T Nurmohamed Joost Dekker Ben AC Dijkmans Irene E van der Horst-Bruinsma 《Arthritis research & therapy》2012,14(2):R52-6
Introduction
Ankylosing Spondylitis (AS) is characterised by limitations in physical function. The Bath Ankylosing Spondylitis Functional Index (BASFI) is considered to be the gold-standard to assess physical function in AS patients. However, the BASFI questionnaire is a self-reported outcome measure and susceptible to subjective interpretation (under- or over-estimation). More objective outcome measures, like performance-based tests, could provide an objective outcome measurement for the evaluation of limitations in physical function. Therefore, the primary aim of this study was to determine the association between performance-based measures and the BASFI questionnaire.Methods
In this cross-sectional study 126 AS patients completed the BASFI questionnaire and eight performance-based tests based on BASFI-items. Each test received three scores: one for performance (time or points) and a score for exertion and pain experienced during performance (using modified Borg-scale and VAS 0-100 mm, respectively). Linear regression analyses were used to assess the associations between the BASFI questionnaire and performance-based tests.Results
The univariable association between performance and BASFI-score was moderate with a R-square of 0.31 and Beta of 0.56 (p's < 0.05). In a multivariable analysis, the association between performance, exertion and pain on the one hand and BASFI-score on the other was assessed; R-square increased to 0.54: the Beta's for exertion and pain during performance were 0.38 and 0.26, respectively; the Beta for performance decreased to 0.19 (p's < 0.05).Conclusions
This study demonstrates that alongside actual performance, patients seem to incorporate exertion and pain in their assessment of perceived physical function on the BASFI questionnaire. Performance-based tests could provide an objective outcome measurement for the evaluation of physical function and give relevant new information in addition to the BASFI questionnaire. 相似文献86.
P M Saling 《Biology of reproduction》1991,44(2):246-251
Although details of the molecular mechanism are not yet clear, considerable evidence suggests that the egg-specific extracellular matrix component ZP3 regulates an essential event of sperm function, the acrosome reaction. Spatial control of this exocytotic event appears to be exerted by immobilization of the triggering ligand, ZP3, in the zona pellucida matrix surrounding the egg. Our data suggest that the signal transduction pathway in sperm activated by this ligand involves highly conserved components that are involved in many other eukaryotic signalling events. Recent experiments indicate that the murine zona pellucida glycoprotein ZP3 regulates acrosomal exocytosis by aggregating its corresponding receptors (ZP3-Rs) located in the mouse sperm plasma membrane. In other experiments, we have identified a putative ZP3-R of mouse sperm with Mr 95,000. Indirect immunofluorescence localizes this ZP3-R, termed p95, to the acrosomal region of the mouse sperm head, which is the anticipated location for ZP3-Rs. Membrane fractionation studies indicate that p95 cofractionates with a plasma membrane-enriched preparation from sperm that contains zona pellucida-receptor activity. In addition to its role as a ZP3-R, p95 also serves as a substrate for a tyrosine kinase in response to zona pellucida binding. On the basis of the data presented here, and borrowing heavily from findings for other signalling systems, we have formulated two testable hypotheses that are compatible with the available data: either p95 is itself a protein tyrosine kinase receptor, or p95 serves as a ZP3 receptor and is separate from a protein tyrosine kinase that is activated during gamete interaction.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
87.
Jennifer H Humphreys Jessica AB van Nies Jackie Chipping Tarnya Marshall Annette HM van der Helm-van Mil Deborah PM Symmons Suzanne MM Verstappen 《Arthritis research & therapy》2014,16(6)
Introduction
This study aimed to investigate rheumatoid factor (RF) and anti-citrullinated protein antibody (ACPA) status and levels as predictors of mortality in two large cohorts of patients with early inflammatory arthritis (EIA).Methods
Data from the Norfolk Arthritis Register (NOAR) and Leiden Early Arthritis Clinic (EAC) cohorts were used. At baseline, patients had demographic data and smoking status recorded; RF, ACPA and inflammatory markers were measured in the local laboratories. Patients were flagged with national death registers until death or censor date. Antibody status was stratified as negative, low or high positive by RF and ACPA levels individually. In addition, patients were grouped as seronegative, RF positive, ACPA positive or double antibody (RF and ACPA) positive. Cox regression models explored associations between antibody status and mortality adjusting for age, sex, smoking status, inflammatory markers and year of enrolment.Results
A total of 4962 patients were included, 64% were female. Median age at onset was 56 (NOAR) and 54 (EAC) years. In NOAR and EAC respectively, 35% and 42% of patients were ACPA/RF positive. When antibody status was stratified as negative, low or high positive, there were no consistent findings between the two cohorts. Double antibody positivity was associated with excess mortality in both cohorts compared to seronegative patients: NOAR and EAC respective adjusted HR (95% confidence interval) 1.35 (1.09 to 1.68) and 1.58 (1.16 to 2.15).Conclusions
Patients with EIA who are seropositive for both RF and ACPA have increased mortality compared to those who are single positive or seronegative. Antibody level in seropositive patients was not consistently associated with excess mortality.Electronic supplementary material
The online version of this article (doi:10.1186/s13075-014-0483-3) contains supplementary material, which is available to authorized users. 相似文献88.
Katherine Lakoski Carmen Williams Patricia Saling 《Molecular reproduction and development》1989,23(1):21-37
Effects of reduced glutathione (GSH), oxidized glutathione (GSSG), or glutathione reductasc (GR) supply were studied on the ability of hamster oocytes to be fertilized by human sperm. Zona-free oocytes were pretreated with these compounds prior to sperm insemination. Oocyte pretreatment with high concentrations of GSH or GSSG (50 or 100 mM. 30 min) significantly increased the penetrated oocyte rate (PR). Polyspermy was not increased except when high concentrations of GSH (100 mM) were used. Incubation of oocytes with GR (1 or 10IU/ml) prior to sperm insemination induced increasing dose-dependent PR. Polyspermy increased significantly with 10 mM GR in oocyte incubation medium. Oocyte incubation for 30 min with the sulfhydryl blocking agent iodoacetamide (1 mM) led to a drastic decrease in oocyte penetration and in polyspermy. Our results demonstrate an original way to increase the efficacy of human-hamster heterospecific fertilization. Various hypotheses are discussed explaining these observations which open new investigations for heterospecific and homospecific in vitro fertilization. 相似文献
89.
Alien fishes are considered a major threat to aquatic biodiversity in South Africa, yet relatively little regional information on their biology and ecology is available for many of these species. Seasonal changes in the diet of the bluegill Lepomis macrochirus in Howieson’s Poort Dam, Grahamstown, were assessed during summer and winter in 2014–2015, using stomach content analysis. In winter, juvenile and adult fish diets were dominated by crustacean zooplankton and insects, respectively. In summer, juvenile fish fed on crustaceans and insects, whereas adults consumed mostly fish eggs, indicating a potential impact by these invasive fish on native fish through oophagy. 相似文献
90.
Molecular evolution of bacteriophages: evidence of selection against the recognition sites of host restriction enzymes 总被引:12,自引:0,他引:12
Restriction enzymes produced by bacteria serve as a defense against
invading bacteriophages, and so phages without other protection would be
expected to undergo selection to eliminate recognition sites for these
enzymes from their genomes. The observed frequencies of all restriction
sites in the genomes of all completely sequenced DNA phages (T7, lambda,
phi X174, G4, M13, f1, fd, and IKe) have been compared to expected
frequencies derived from trinucleotide frequencies. Attention was focused
on 6-base palindromes since they comprise the typical recognition sites for
type II restriction enzymes. All of these coliphages, with the exception of
lambda and G4, exhibit significant avoidance of the particular sequences
that are enterobacterial restriction sites. As expected, the sequenced
fraction of the genome of phi 29, a Bacillus subtilis phage, lacks Bacillus
restriction sites. By contrast, the RNA phage MS2, several viruses that
infect eukaryotes (EBV, adenovirus, papilloma, and SV40), and three
mitochondrial genomes (human, mouse, and cow) were found not to lack
restriction sites. Because the particular palindromes avoided correspond
closely with the recognition sites for host enzymes and because other
viruses and small genomes do not show this avoidance, it is concluded that
the effect indeed results from natural selection.
相似文献