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1.
Purpose

The European Commission is thinking about policy options for the European Environmental Footprint (EF) method and aims for a broad support. The SwitchMed initiative is a programme with the overall objective to facilitate the shift towards sustainable consumption and production in the Southern Mediterranean region. One of the objectives of this initiative, carried out in Egypt, Lebanon, Morocco, and Tunisia, is to facilitate access of companies from this region to the outcomes of the EF Rules pilot phase.

Methods

The project was composed of three consecutive phases: (I) awareness raising; (II) local pilots; and (III) dissemination events. The awareness raising and technical workshop activities were meant to expose national stakeholders to the potential impact of the EF system for the national economies. Next, nine environmental footprint studies for selected product categories (so-called PEF pilot studies) were performed to create local capacity and expertise. These were leather and intermediate paper product for Egypt; two studies on wine and one on intermediate paper product in Lebanon; olive oil for Morocco; and pasta, olive oil, and dairy for Tunisia. The learnings from the pilot studies were shared in national dissemination events and used to formulate recommendations for enabling EF-compliant studies in regions outside of Europe.

Results and discussion

There was high attendance to the awareness events in each country. The pilot studies showed many similarities with the European screening studies, but also important differences in the identification of most relevant impact categories, life cycle stages, and processes (‘hotspots analyses’), e.g. related to the local scarcity of water. Based on their pilot study, the local experts made concrete suggestions for shifting towards more sustainable consumption and production. One of the biggest successes of this project is that a couple of these recommendations have already been taken into account by the companies.

Conclusions and recommendations

In Egypt, Lebanon, and Tunisia, a few local experts with a significant level of LCA expertise could be identified and through this project we managed to create local PEF capacity too. In Morocco, more assistance was needed to finish the pilot study. This project made clear that the current ‘PEF and OEF methods’ have serious drawbacks for regions other than Europe. The rules of the EF method need to be reconsidered in order to enable EF-compliant studies in regions outside of Europe. In short, we recommend:

  1. 1.

    Developing databases with local inventory data for regions outside of Europe;

  2. 2.

    Enlarging access to EF-compliant data by extension of the free access and by facilitation of the availability of conversion tools;

  3. 3.

    Taking the local availability of data into account when setting data quality requirements;

  4. 4.

    Adapting the rules for data collection and quality to allow for more precise adaptations;

  5. 5.

    Including in the PEFCR development, supporting studies for products manufactured outside the EU and/or in a geography with unusual conditions; and

  6. 6.

    Updating existing rules specific for certain product categories regularly.

  相似文献   

2.
Abstract

Sinusichnus Gibert 1996 Gibert, J. M. d. 1996. “A New Decapod Burrow System from the NW Mediterranean Pliocene.” Revista Española de Paleontología 11: 251254. [Google Scholar] is recorded for the first time in the Oligocene-Miocene Pirabas Formation of Northern Brazil. In these Oligocene-Miocene carbonate deposits, Sinusichnus sinuosus is characterized by horizontal, highly regular sinusoidal burrow systems with T- and H-shaped branching points. The main difference between the S. sinuosus described herein and other occurrences worldwide is the anomalous diameter of the burrows (4 to 10?cm). These trace fossils occur in organic matter-rich, wackestone/packstone and laminated mudstones interbedded with boundstones deposited in an inner carbonate platform paleoenvironment. The exceptional size of the studied S. sinuosus could have been associated to the producer’s size, which may be attributed to construction by large crustaceans, similar to fossils found within the Pirabas Formation. Also, the sinusoidal morphology and retrusive spreiten could be a result of the fodinichnial/domichnial behavior.  相似文献   

3.
Abstract

The ichnospecies Gastrochaneolites dijugus Kelly and Bromley 1984 Kelly, S. R. A., and R. G. Bromley. 1984. “Ichnological Nomenclature of Clavate Borings.” Palaeontology 27: 793807.[Web of Science ®] [Google Scholar] and Teredolites longissimus Kelly and Bromley 1984 Kelly, S. R. A., and R. G. Bromley. 1984. “Ichnological Nomenclature of Clavate Borings.” Palaeontology 27: 793807.[Web of Science ®] [Google Scholar], attributed to the boring activity of gastrochaenoid and pholadid bivalves, are described respectively from the Miocene Vilanova Basin and the Pliocene Almería-Níjar Basin. Miocene and Pliocene traces are preserved as positive casts associated to invertebrate shells and wood fragments, respectively; in both cases, the host substrate (shells and wood) has been lost almost entirely by different taphonomic processes (mainly dissolution). For the first time in the fossil record, the complete ichnogenetic sequence of these two ichnospecies is described and figured.  相似文献   

4.
Abstract

The demand to repair areas contaminated with hydrocarbon products has led to the development of new technologies for the treatment of contaminants in an unconventional method, that is, no physical or chemical methods are used. Biosurfactants are amphiphilic biomolecules produced by microorganisms that can be used in environments contaminated by petroleum products due to their unexceptionable tensile properties. Petroleum degrading strain Rhodococcus erythropolis HX-2 was found to be an effective producer of biosurfactants. The resulting biosurfactant (named NK) exhibits high physicochemical properties in terms of surface activity. It is capable of reducing surface tension from 54.99 to 28.89?mN/m and critical micelle concentration (CMC) is 100?mg/L. NK was found to be a substitute for chemically synthesized surfactants because of its higher solubilization efficiency for petroleum and polycyclic aromatic hydrocarbons, superior to SDS, Tween 80, Triton X-100 and Rhamnolipid (a wide used biosurfactant). In addition, it exhibits favorable emulsion stability over a wide range of pH (3–10), temperature (20–100?°C) and salinity ranges (5–20?g/L). It was found that the addition of biosurfactant can improve the efficiency of petroleum degradation, therefore it has potential applications in bioremediation.
  • Highlights
  • Rhodococcus erythropolis HX-2 is an effective petroleum degrading strain.

  • HX-2 is a potential source of biosurfactant production.

  • The biosurfactant NK reduces surface tension and exhibits high emulsification activity.

  • The biosurfactant NK is effective over a wide range of temperatures, pH and salinity.

  • The biosurfactant NK shows high solubilization efficiency for petroleum as well as polycyclic aromatic hydrocarbons.

  相似文献   

5.
During the course of studies on the oxidative metabolism of d-sorbitol by acetic acid bacteria, it was found that d-sorbitol was almost quantitatively converted to 5-keto-d-fructose via l-sorbose by a certain strain of Gluconobacter suboxydans. In addition to 5-keto-d-fructose, three γ-pyrone compounds, kojic acid, 5-oxymaltol, and 3-oxykojic acid, 2-keto-l-gulonate, and several organic acids such as succinic, glycolic, and glyceric acids were confirmed in the culture filtrate of this bacterium.
  • The most suitable carbon source for 5-ketofructose fermentation by Gluconobacter suboxydans Strain 1 was confirmed to be d-sorbitol or l-sorbose using growing and resting cells. d-Fructose had little effect on the formation of this dicarbonylhexose.

  • The optimal pH for the formation from l-sorbose by intact cells was found to be at 4.2.

  • The activity of the pentose phosphate cycle in the resting cells was calculated as 13~17 μatoms/hr/mg of dry cells by the use of the manometric techniques.

  • There was no strain tested so far which could accumulate a large amount of 5- keto-d-fructose from d-sorbitol except this bacterium.

  • The experimental results shown in this paper makes the prediction that a certain dehydrogenating system of l-sorbose is functional in the organism, and the metabolic pathways of d-sorbitol via l-sorbose and 5-keto-d-fructose is proposed.

  相似文献   

6.
  1. L-Asparaginase (EC 3.5.1.1) from Escherichia coli A–l–3 was acetylated using acetic anhydride as a modifying chemical. The fully acetylated L-asparaginase retained 60% of the activity of the unmodified L-asparaginase.

  2. The acetylated L-asparaginase hydrolyzed D-asparagine and L-glutamine as well as L-asparagine in the same ratio as the unmodified L-asparaginase did.

  3. However, the effects of pH on the activity of the acetylated L-asparaginase showed very interesting differences from that of L-asparaginase. On the other hand, both L-asparaginase and the acetylated L-asparaginase exhibited similar pH activity curves on L-glutamine hydrolysis.

  4. The acetylated L-asparaginase was found to become more stable against acid or heat in the presence of L-aspartate than in its absence in the same manner as L-asparaginase was.

  相似文献   

7.
  1. l-Aspartate was found to replace l-asparagine in the protective action from acid inactivation of l-asparaginase (EC 3.5.1.1) produced by Escherichia coli A–1–3 and at the same time to inhibit the proteolytic inactivation by α-chymotrypsin.

  2. l-Asparaginase changed in its chromatographic properties in the presence of l-aspartate and became to be absorbed on the CM Sephadex column.

  3. The sedimentation patterns of l-asparaginase at pH 3.5 were identical either in the presence or absence of l-aspartate, showing partial dissociation. But the reversibility to the active state was observed only in the enzyme dissolved in the solution containing l-aspartate.

  4. l-Aspartate did not prevent the enzyme either from the dissociation into subunits or from decrease in the activity by urea.

  5. High concentration of l-aspartate was shown to inhibit the l-asparagine hydrolysis reaction.

  6. l-Aspartate was suggested from ORD measurements to cause changes in the higher structure as well as the ionic properties or proteolytic inactivation.

  相似文献   

8.

Purpose

Pharmaceutical and biological materials require thermally controlled environments when being transported between manufacturers, clinics, and hospitals. It is the purpose of this report to compare the life cycle impacts of two distinct logistical approaches to packaging commonly used in cold chain logistics and to identify the method of least environmental burden. The approaches of interest are single-use packaging utilizing containers insulated with either polyurethane or polystyrene and reusable packaging utilizing containers with vacuum-insulated panels.

Methods

This study has taken a cradle-to-grave perspective, which covers material extraction, manufacture, assembly, usage, transportation, and end-of-life realities. The functional unit of comparison is a 2-year clinical trial consisting of 30,000 individual package shipments able to maintain roughly 12 L of payload at a controlled 2–8 °C temperature range for approximately 96 h. Published life-cycle inventory data were used for process and material emissions. A population-centered averaging method was used to estimate transportation distances to and from clinical sites during container use. Environmental impacts of the study include global warming potential, eutrophication potential, acidification potential, photochemical oxidation potential, human toxicity potential, and postconsumer waste.

Results and discussion

The average single-use approach emits 1,122 tonnes of CO2e compared with 241 tonnes with the reusable approach over the functional unit. This is roughly a 75 % difference in global warming potential between the two approaches. Similar differences exist in other impact categories with the reusable approach showing 60 % less acidification potential, 65 % less eutrophication potential, 85 % less photochemical ozone potential, 85 % less human toxicity potential, and 95 % less postconsumer waste. The cradle-to-gate emissions of the single-use container were the overwhelming cause of its high environmental burden as 30,000 units were required to satisfy the functional unit rather than 772 for the reusable approach. The reusable container was about half the mass of the average single-use container, which lowered its transportation emissions below the single-use approach despite an extra leg of travel.

Conclusions

The reusable logistical approach has shown to impose a significantly smaller environmental burden in all impact categories of interest. A sensitivity analysis has shown some leeway in the degree of the environmental advantage of the reusable approach, but it confirms the conclusion as no case proved otherwise.  相似文献   

9.

Masking in motor systems was defined as the omission of one act in a sequence due to an earlier or later act in the sequence. A study of phoneme omission in natural speech showed that:

  1. 1.

    Masked phonemes were usually preceded or followed by an identical phoneme (referred to as the masking phoneme).

  2. 2.

    Backward masking, where the masked phoneme preceded the masking phoneme was as frequent as forward masking.

  3. 3.

    The phonemes immediately adjacent to the masked and masking phonemes were usually similar in distinctive features, but rarely identical.

  4. 4.

    The masking phoneme usually occurred in a stressed syllable and the masked phoneme in an unstressed one, suggesting that motor intensity may be a factor in masking.

  5. 5.

    The components for an adequate model of motor masking were shown to be similar to those in models of other types of errors in speech.

  相似文献   

10.
11.
Zhang  Jiaxian  Jing  Yu  Zhang  Hu  Liu  Ping 《Amino acids》2021,53(9):1441-1454

l-arginine is a versatile amino acid with a number of bioactive metabolites. Increasing evidence implicates altered arginine metabolism in the aging and neurodegenerative processes. The present study, for the first time, determined the effects of sex and estrous cycle on the brain and blood (plasma) arginine metabolic profile in naïve rats. Female rats displayed significantly lower levels of l-arginine in the frontal cortex and three sub-regions of the hippocampus when compared to male rats. Moreover, female rats had significantly higher levels of l-arginine and γ-aminobutyric acid, but lower levels of l-ornithine, agmatine and putrescine, in plasma relative to male rats. The observed sex difference in brain l-arginine appeared to be independent of the enzymes involved in its metabolism, de novo synthesis and blood-to-brain transport (cationic acid transporter 1 protein expression at least), as well as circulating l-arginine. While the estrous cycle did not affect l-arginine and its metabolites in the brain, there were estrous cycle phase-dependent changes in plasma l-arginine. These findings demonstrate the sex difference in brain l-arginine in the estrous cycle-independent manner. Since peripheral blood has been increasingly used to identify biomarkers of brain pathology, the influences of sex and estrous cycle on blood arginine metabolic profile need attention when experimental research involves female rodents.

  相似文献   

12.
Abstract

Fungi of the Trichoderma species are valued industrial enzymes in support of the ‘zero-waste’ technology to convert agro-industrial biomass into valuable products, i.e. nanocellulose (NC). In this study, an in silico approach using substrate docking and molecular dynamic (MD) simulation was used to predict the order of which the multilayers of cellulosic polymers, i.e. lignin, hemicellulose and cellulose in oil palm leaves (OPL) are degraded by fungal enzymes, endocellulase and exocellulase. The study aimed to establish the catalytic tendencies of the enzymes to optimally degrade the cellulosic components of OPL for high yield production of NC. Energy minimized endocellulase and exocellulase models revealed satisfactory scores of PROCHECK (90.0% and 91.2%), Verify3D (97.23% and 98.85%) and ERRAT (95.24% and 91.00%) assessments. Active site prediction by blind docking, COACH meta-server and multiple sequence alignment indicated the catalytic triads for endocellulase and exocellulase were Ser116–His205–Glu249 and Ser382–Arg124–Asp385, respectively. Binding energy of endocellulase docked with hemicellulose (?6.0 ? kcal mol?1) was the most favourable followed by lignin (?5.6 ? kcal mol?1) and cellulose (?4.4 ? kcal mol?1). Exocellulase, contrarily, bonded favorably with lignin (?8.7 ? kcal mol?1), closely followed by cellulose (?8.5 ? kcal mol?1) and hemicellulose (?8.4 ? kcal mol?1). MDs simulations showed that interactions of complexes, endocellulase–hemicellulose and the exocellulase–cellulose being the most stable. Thus, the findings of the study successfully identified the specific actions of sugar-acting enzymes for NC production.

Communicated by Ramaswamy H. Sarma  相似文献   

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18.
Wanink  Jan H.  Goudswaard  Kees 《Hydrobiologia》1994,279(1):367-376

In recent years the ichthyofauna of Lake Victoria, the world's largest tropical lake, has gone through dramatic changes. The population of Nile perch, a large predator which has been introduced into the lake by man, increased explosively at the expense of many haplochromine cichlid species. At the same time, numbers of a small cyprinid (dagaa) rose sharply.

Previously Pied Kingfishers on Lake Victoria fed mainly on haplochromines. Only the youngest nestlings depended on dagaa as primary food. The current diet of adult birds clearly reflects the changes which have occurred in the fish community. Pellet analysis reveals a shift towards a diet composed of almost 100% dagaa.

The change in prey species composition has increased the number of fish a kingfisher needs to catch daily in order to meet its energetic demands, because:

  1. (1)

    the mean size of haplochromines is larger than that of dagaa;

  2. (2)

    (2) the mean size of dagaa has decreased since the increase in Nile perch;

  3. (3)

    (3) the weight of dagaa is lower than that of haplochromines of equal size;

  4. (4)

    (4) mainly juvenile dagaa and adults in poor condition are accessible to kingfishers.

  相似文献   

19.
Abstract

Alkaline-stable lipases are highly valuable biocatalysts that catalyze reactions under highly basic conditions. Herein, computational predictions of lipase from Acinetobacter haemolyticus and its mutant, Mut-LipKV1 was performed to identify functionally relevant mutations that enhance pH performance under increasing basicity. Mut-LipKV1 was constructed by in silico site directed mutagenesis of several outer loop acidic residues, aspartic acid (Asp) into basic ones, lysine (Lys) at positions 51, 122 and 247, followed by simulation under extreme pH conditions (pH 8.0–pH 12.0). The energy minimized Mut-LipKV1 model exhibited good quality as shown by PROCHECK, ERRAT and Verify3D data that corresponded to 79.2, 88.82 and 89.42% in comparison to 75.2, 86.15, and 95.19% in the wild-type. Electrostatic surface potentials and charge distributions of the Mut-LipKV1 model was more stable and better adapted to conditions of elevated pHs (pH 8.0???10.0). Mut-LipKV1 exhibited a mixture of neutral and positive surface charge distribution compared to the predominantly negative charge in the wild-type lipase at pH 8.0. Data of molecular dynamics simulations also supported the increased alkaline-stability of Mut-LipKV1, wherein the lipase was more stable at a higher pH 9.0 (RMSD = ~0.3?nm, RMSF = ~0.05–0.2?nm), over the optimal pH 8.0 of the wild-type lipase (RMSD = 0.3?nm, RMSF = 0.05–0.20?nm). Thus, the adaptive strategy of replacing surface aspartic acid to lysine in lipase was successful in yielding a more alkaline-stable Mut-LipKV1 under elevated basic conditions.

Communicated by Ramaswamy H. Sarma  相似文献   

20.
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