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43.
Carles M. Gasol Ramon Farreny Xavier Gabarrell Joan Rieradevall 《The International Journal of Life Cycle Assessment》2008,13(5):421-431
Goal, scope and background The industrial packages sector has great importance for the transport sector in Europe. These containers, mainly wooden pallets
and spools, are subject to European legislation, which promotes their reuse and recycling. This study uses life cycle assessment
(LCA) to assess the environmental impact of the current management system in this sector and the benefits and drawbacks of
different reuse intensities as a waste prevention strategy as opposed to the recycling option.
Materials and methods In this paper, four case studies located in Spain and representative of the wooden package sector in Europe are analysed:
high reuse pallet, low reuse pallet, low reuse spool and null reuse spool. For the LCA study cases, the functional unit is
that required to satisfy the transport necessity of 1,000 t by road. The impact and energy consumption assessment methods
used are CML 2 Baseline 2000 and Cumulative Energy Demand. Data are mostly provided by the leading enterprises and organisations
in this sector.
Results The paper provides, as a first result, a comprehensive inventory of the systems under study. Secondly, our assessment shows
that the systems with higher reuse intensity show a reduction in energy and wood consumption and all the environmental impact
categories except for the global warming potential from 34.0% to 81.0% in the pallet study cases and from 50.4% to 72.8% in
the spool ones. This reduction is at the expense of the maintenance stage, which on the contrary increases its impact, although
it is still relatively small—less than 7% in all the impact categories and flow indicators of the study cases. The highest
impact stages are transport, raw material extraction and the process chain. The final disposal and maintenance stages are
the lowest impact, contributing at most to less than 30% of the impact in the pallet study cases and 10% in the spool cases.
Discussion Wood consumption (WC), directly related to the number of containers needed to satisfy the functional unit, is the main factor
in determining the impact of the stages, especially in the raw materials extraction and process chain stages, assuming that
these are undertaken with the same technologies in all the case studies. Other variables, such as the management system, the
maintenance index and the final disposal scenario, affect the impact of the remaining stages: transport, maintenance and final
disposal. The global warming potential results obtained demonstrate the environmental benefits of using containers made of
a renewable resource such as wood instead of using other materials, but these results are not expected to prioritise the lower
reuse systems because of their better performance in this category.
Conclusions Reuse, a strategy capable of reducing the environmental impacts of the wooden container systems, is preferable to recycling,
while the package maintenance tasks are still feasible. Therefore, reuse, combined with recycling as final disposal, should
be encouraged to reduce the demand for natural resources and the waste generated.
Recommendations Based on these results, attention should be paid to the maintenance stage, which, being the lowest-impact one, could substantially
reduce the impact of the remaining stages. 相似文献
44.
Laura Brugnara Roger Mallol Josep Ribalta Maria Vinaixa Serafín Murillo Teresa Casserras Montse Guardiola Joan Carles Vallvé Susana G. Kalko Xavier Correig Anna Novials 《PloS one》2015,10(8)
Patients with type 1 diabetes (T1D) present increased risk of cardiovascular disease (CVD). The aim of this study is to improve the assessment of lipoprotein profile in patients with T1D by using a robust developed method 1H nuclear magnetic resonance spectroscopy (1H NMR), for further correlation with clinical factors associated to CVD. Thirty patients with T1D and 30 non-diabetes control (CT) subjects, matched for gender, age, body composition (DXA, BMI, waist/hip ratio), regular physical activity levels and cardiorespiratory capacity (VO2peak), were analyzed. Dietary records and routine lipids were assessed. Serum lipoprotein particle subfractions, particle sizes, and cholesterol and triglycerides subfractions were analyzed by 1H NMR. It was evidenced that subjects with T1D presented lower concentrations of small LDL cholesterol, medium VLDL particles, large VLDL triglycerides, and total triglycerides as compared to CT subjects. Women with T1D presented a positive association with HDL size (p<0.005; R = 0.601) and large HDL triglycerides (p<0.005; R = 0.534) and negative (p<0.005; R = -0.586) to small HDL triglycerides. Body fat composition represented an important factor independently of normal BMI, with large LDL particles presenting a positive correlation to total body fat (p<0.005; R = 0.505), and total LDL cholesterol and small LDL cholesterol a positive correlation (p<0.005; R = 0.502 and R = 0.552, respectively) to abdominal fat in T1D subjects; meanwhile, in CT subjects, body fat composition was mainly associated to HDL subclasses. VO2peak was negatively associated (p<0.005; R = -0.520) to large LDL-particles only in the group of patients with T1D. In conclusion, patients with T1D with adequate glycemic control and BMI and without chronic complications presented a more favourable lipoprotein profile as compared to control counterparts. In addition, slight alterations in BMI and/or body fat composition showed to be relevant to provoking alterations in lipoproteins profiles. Finally, body fat composition appears to be a determinant for cardioprotector lipoprotein profile. 相似文献
45.
Santiago Tofé Povedano Iñaki Argüelles Jiménez Honorato García Fernández Julia Quevedo Juanals Sergio Díaz Medina Guillermo Serra Soler Bartolomé Burguera González Mercedes Codina Marcet Elena Mena Ribas Juan Ramón Urgeles Planella Vicente Pereg Macazaga 《Endocrinología y nutrición》2010,57(2):43-48
IntroductionFine-needle aspiration biopsy (FNAB) is considered the reference diagnostic procedure for thyroid nodules.Materials and methodsRoutine performance of thyroid ultrasound and ultrasound-guided FNAB by endocrinologists allows a more efficient approach in the setting of a high-resolution practice, thus reducing costs and the time elapsed until diagnosis.ResultsWe present our initial results of this procedure 2 years after its introduction, with a total of 286 biopsies performed. After a progressive learning curve over time and according to the endocrinologists’ previous experience, 72.72% samples were considered satisfactory for diagnosis. Greater difficulty was observed in obtaining optimal cytological specimens in smaller nodules. In conclusion, we have successfully incorporated thyroid ultrasound and ultrasound-guided FNAB into routine endocrine practice.ConclusionRoutine performance of thyroid ultrasound in endocrine practice will considerably aid the management of nodular thyroid disease. 相似文献
46.
Cantó C Suárez E Lizcano JM Griñó E Shepherd PR Fryer LG Carling D Bertran J Palacín M Zorzano A Gumà A 《The Journal of biological chemistry》2004,279(13):12260-12268
Neuregulin-1, a growth factor that potentiates myogenesis induces glucose transport through translocation of glucose transporters, in an additive manner to insulin, in muscle cells. In this study, we examined the signaling pathway required for a recombinant active neuregulin-1 isoform (rhHeregulin-beta(1), 177-244, HRG) to stimulate glucose uptake in L6E9 myotubes. The stimulatory effect of HRG required binding to ErbB3 in L6E9 myotubes. PI3K activity is required for HRG action in both muscle cells and tissue. In L6E9 myotubes, HRG stimulated PKBalpha, PKBgamma, and PKCzeta activities. TPCK, an inhibitor of PDK1, abolished both HRG- and insulin-induced glucose transport. To assess whether PKB was necessary for the effects of HRG on glucose uptake, cells were infected with adenoviruses encoding dominant negative mutants of PKBalpha. Dominant negative PKB reduced PKB activity and insulin-stimulated glucose transport but not HRG-induced glucose transport. In contrast, transduction of L6E9 myotubes with adenoviruses encoding a dominant negative kinase-inactive PKCzeta abolished both HRG- and insulin-stimulated glucose uptake. In soleus muscle, HRG induced PKCzeta, but not PKB phosphorylation. HRG also stimulated the activity of p70S6K, p38MAPK, and p42/p44MAPK and inhibition of p42/p44MAPK partially repressed HRG action on glucose uptake. HRG did not affect AMPKalpha(1) or AMPKalpha(2) activities. In all, HRG stimulated glucose transport in muscle cells by activation of a pathway that requires PI3K, PDK1, and PKCzeta, but not PKB, and that shows cross-talk with the MAPK pathway. The PI3K, PDK1, and PKCzeta pathway can be considered as an alternative mechanism, independent of insulin, to induce glucose uptake. 相似文献
47.
Laurent Bertoletti Sara Quenet Silvy Laporte Joan Carles Sahuquillo Francisco Conget José María Pedrajas Mar Martin Ignacio Casado Antonio Riera-Mestre Manuel Monreal 《Respiratory research》2013,14(1):75
Background
Patients with chronic obstructive pulmonary disease (COPD) have a modified clinical presentation of venous thromboembolism (VTE) but also a worse prognosis than non-COPD patients with VTE. As it may induce therapeutic modifications, we evaluated the influence of the initial VTE presentation on the 3-month outcomes in COPD patients.Methods
COPD patients included in the on-going world-wide RIETE Registry were studied. The rate of pulmonary embolism (PE), major bleeding and death during the first 3 months in COPD patients were compared according to their initial clinical presentation (acute PE or deep vein thrombosis (DVT)).Results
Of the 4036 COPD patients included, 2452 (61%; 95% CI: 59.2-62.3) initially presented with PE. PE as the first VTE recurrence occurred in 116 patients, major bleeding in 101 patients and mortality in 443 patients (Fatal PE: first cause of death). Multivariate analysis confirmed that presenting with PE was associated with higher risk of VTE recurrence as PE (OR, 2.04; 95% CI: 1.11-3.72) and higher risk of fatal PE (OR, 7.77; 95% CI: 2.92-15.7).Conclusions
COPD patients presenting with PE have an increased risk for PE recurrences and fatal PE compared with those presenting with DVT alone. More efficient therapy is needed in this subtype of patients. 相似文献48.
49.
Upper Hauterivian reefal carbonates of the Llàcova Formation (Maestrat Basin, Iberian Chain, E Spain) contain Sporolithon phylloideum (Bucur and Dragastan) Tomás, Aguirre, Braga and Martín-Closas comb. nov. and Sporolithon rude (Lemoine) Ghosh and Maithy (1996). Moussavian et al. (1993) identified them as Parakymalithon phylloideum (Bucur and Dragastan) Moussavian 1987 and Archaeolithothamnium rude Lemoine 1925. The re-assessment of the type of P. phylloideum and additional material indicate that the diagnostic characters of the genus do not warrant separation from Sporolithon and the new combination Sporolithon phylloideum is proposed. The lectotype of Sporolithon rude presents sporangial cavities grouped in sori that can be merged originating a structure that resembles the multiporate tetrasporangial
conceptacles of the Hapalidiaceae. We hypothesize that multiporate tetrasporangial conceptacles could have originated from
the fusion of several sporangial cavities, suggesting a phylogenetic linkage between Sporolithaceae and Hapalidiaceae supported
by other anatomical features, molecular phylogeny and the fossil record. 相似文献
50.
Helgason A Pálsson S Lalueza-Fox C Ghosh S Sigurdardóttir S Baker A Hrafnkelsson B Arnadóttir L Thorsteinsdóttir U Stefánsson K 《Journal of molecular evolution》2007,65(1):92-102
One of the key problems in the study of ancient DNA is that of authenticating sequences obtained from PCR amplifications of
highly degraded samples. Contamination of ancient samples and postmortem damage to endogenous DNA templates are the major
obstacles facing researchers in this task. In particular, the authentication of sequences obtained from ancient human remains
is thought by many to be rather challenging. We propose a novel approach, based on the c statistic, that can be employed to help identify the sequence motif of an endogenous template, based on a sample of sequences
that reflect the nucleotide composition of individual template molecules obtained from ancient tissues (such as cloned products
from a PCR amplification). The c statistic exploits as information the most common form of postmortem damage observed among clone sequences in ancient DNA
studies, namely, lesion-induced substitutions caused by cytosine deamination events. Analyses of simulated sets of templates
with miscoding lesions and real sets of clone sequences from the literature indicate that the c-based approach is highly effective in identifying endogenous sequence motifs, even when they are not present among the sampled
clones. The proposed approach is likely to be of general use to researchers working with DNA from ancient tissues, particularly
from human remains, where authentication of results has been most challenging.
[Reviewing
Editor: Dr. Magnus Nordborg] 相似文献