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81.
Purpose

A review of LCA process datasets is an important element of quality assurance for databases and for other systems to provide LCA datasets. Somewhat surprisingly, a broadly accepted and applicable set of criteria for a review of LCA process datasets was lacking so far. Different LCA databases and frameworks are proposing and using different criteria for reviewing datasets. To close this gap, a set of criteria for reviewing LCA dataset has been developed within the Life Cycle Initiative.

Methods

Previous contributions to LCA dataset review have been analysed for a start, from ISO and various LCA databases. To avoid somewhat arbitrary review criteria, four basic rules are proposed which are to be fulfilled by any dataset. Further, concepts for assessing representativeness and relevance are introduced into the criteria set from established practices in statistics and materiality. To better structure the criteria and to ease their application, they are grouped into clusters. A first version of the developed review criteria was presented in two workshops with database providers and users on different levels of experience, and draft versions of the criteria were shared within the initiative. The current version of the criteria reflects feedback received from various stakeholders and has been applied and tested in a review for newly developed datasets in Brazil, Malaysia and Thailand.

Results and discussion

Overall, 14 criteria are proposed, which are organised in clusters. The clusters are goal, model, value, relevance and procedure. For several criteria, a more science-based definition and evaluation is proposed in comparison to ‘traditional’ LCA. While most of the criteria depend on the goal and scope of dataset development, a core set of criteria are seen as essential and independent from specific LCA modelling. For all the criteria, value scales are developed, typically using an ordinal scale, following the pedigree approach.

Conclusions

Review criteria for LCI datasets are now defined based on a stringent approach. They aim to be globally acceptable, considering also database interoperability and database management aspects, as well as feedback received from various stakeholders, and thus close an important gap in LCA dataset quality assurance. The criteria take many elements of already existing criteria but are the first to fully reflect the implications of the ISO data quality definition, and add new concepts for representativeness and relevance with the idea to better reflect scientific practice outside of the LCA domain. A first application in a review showed to be feasible, with a level of effort similar to applying other review criteria. Aspects not addressed yet are the review procedure and the mutual recognition of dataset reviews, and their application for a very high number of datasets.

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This study aimed to evaluate the impact of aerobic training (AT) on autonomic, cardiometabolic, ubiquitin‐proteasome activity, and inflammatory changes evoked by myocardial infarction (MI) in ovariectomized rats. Female Wistar rats were ovariectomized and divided into four groups: sedentary + sham (SS), sedentary + MI (SI), AT + sham surgery (TS), AT + MI (TI). AT was performed on a treadmill for 8 weeks before MI. Infarcted rats previously subjected to AT presented improved physical capacity, increased interleukin‐10, and decreased pro‐inflammatory cytokines. Metabolomic analysis identified and quantified 62 metabolites, 9 were considered significant by the Vip Score. SS, SI, and TS groups presented distinct metabolic profiles; however, TI could not be distinguished from the SS group. MI dramatically increased levels of dimethylamine, and AT prevented this response. Our findings suggest that AT may be useful in preventing the negative changes in functional, inflammatory, and metabolic parameters related to MI in ovariectomized rats.  相似文献   
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Probiotics and Antimicrobial Proteins - Probiotics represent a possible strategy for controlling intestinal infections in livestock. Members of the Weissella genus are increasingly being studied...  相似文献   
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A really unexpected finding of sauropod and theropod footprints in southern Latium raises to four the number of the trampled levels recognized in central and southern Italy. After the recent findings in Latest Jurassic and Early, mid and Late Cretaceous carbonate platform deposits of the Periadriatic region, dinosaur footprints seem to provide very important paleogeographic constraints for reconstructing the geodynamic history of the Mediterranean area. The presence of a varied ichnoassociation makes acceptance of the current paleogeographic models concerning the relative and absolute position of the Laziale-Abruzzese-Campano and of Apulian-Dinaric domains during the Late Cretaceous more and more problematic. Dinosaur footprints, combined with other paleontological data, demonstrate that these areas were never completely pulled apart by deep seaways, while frequent or continuous links between them, and to southern and northern mainlands, probably persisted. These data also allowed us to improve our understanding of the timing of the Mesozoic plate motion in this segment of the Western Tethys.  相似文献   
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Background: The uptake and biotransformation of γ-tocopherol (γ-T) in humans is largely unknown. Using a stable isotope method we investigated these aspects of γ-T biology in healthy volunteers and their response to γ-T supplementation.

Methods: A single bolus of 100 mg of deuterium labeled γ-T acetate (d2-γ-TAC, 94% isotopic purity) was administered with a standard meal to 21 healthy subjects. Blood and urine (first morning void) were collected at baseline and a range of time points between 6 and 240 h post-supplemetation. The concentrations of d2 and d0-γ-T in plasma and its major metabolite 2,7,8-trimethyl-2-(b-carboxyethyl)-6-hydroxychroman (-γ-CEHC) in plasma and urine were measured by GC-MS. In two subjects, the total urine volume was collected for 72 h post-supplementation. The effects of γ-T supplementation on α-T concentrations in plasma and α-T and γ-T metabolite formation were also assessed by HPLC or GC-MS analysis.

Results: At baseline, mean plasma α-T concentration was approximately 15 times higher than γ-T (28.3 vs. 1.9 µmol/l). In contrast, plasma γ-CEHC concentration (0.191 µmol/l) was 12 fold greater than α-CEHC (0.016 µmol/l) while in urine it was 3.5 fold lower (0.82 and 2.87 µmol, respectively) suggesting that the clearance of α-CEHC from plasma was more than 40 times that of γ-CEHC. After d2-γ-TAC administration, the d2 forms of γ-T and γ-CEHC in plasma and urine increased, but with marked inter-individual variability, while the d0 species were hardly affected. Mean total concentrations of γ-T and γ-CEHC in plasma and urine peaked, respectively, between 0–9, 6–12 and 9–24 h post-supplementation with increases over baseline levels of 6–14 fold. All these parameters returned to baseline by 72 h. Following challenge, the total urinary excretion of d2-γ-T equivalents was approximately 7 mg. Baseline levels of γ-T correlated positively with the post-supplementation rise of (d0 + d2) – γ – T and γ-CEHC levels in plasma, but correlated negatively with urinary levels of (d0 + d2)-γ-CEHC. Supplementation with 100 mg γ-TAC had minimal influence on plasma concentrations of α-T and α-T-related metabolite formation and excretion.

Conclusions: Ingestion of 100mg of γ-TAC transiently increases plasma concentrations of γ-T as it undergoes sustained catabolism to CEHC without markedly influencing the pre-existing plasma pool of γ-T nor the concentration and metabolism of α-T. These pathways appear tightly regulated, most probably to keep high steady-state blood ratios α-T to γ-T and γ-CEHC to α-CEHC.  相似文献   
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