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961.

Purpose

The year-round supply of fresh fruit and vegetables in Europe requires a complex logistics system. In this study, the most common European fruit and vegetable transport packaging systems, namely single-use wooden and cardboard boxes and re-useable plastic crates, are analyzed and compared considering environmental, economic, and social impacts.

Methods

The environmental, economic, and social potentials of the three transport packaging systems are examined and compared from a life cycle perspective using Life Cycle Assessment (LCA), Life Cycle Costing (LCC) and Life Cycle Working Environment (LCWE) methodologies. Relevant parameters influencing the results are analyzed in different scenarios, and their impacts are quantified. The underlying environmental analysis is an ISO 14040 and 14044 comparative Life Cycle Assessment that was critically reviewed by an independent expert panel.

Results and discussion

The results show that wooden boxes and plastic crates perform very similarly in the Global Warming Potential, Acidification Potential, and Photochemical Ozone Creation Potential categories; while plastic crates have a lower impact in the Eutrophication Potential and Abiotic Resource Depletion Potential categories. Cardboard boxes show the highest impacts in all assessed categories. The analysis of the life cycle costs show that the re-usable system is the most cost effective over its entire life cycle. For the production of a single crate, the plastic crates require the most human labor. The share of female employment for the cardboard boxes is the lowest. All three systems require a relatively large share of low-qualified employees. The plastic crate system shows a much lower lethal accident rate. The higher rate for the wooden and cardboard boxes arises mainly from wood logging. In addition, the sustainability consequences due to the influence of packaging in preventing food losses are discussed, and future research combining aspects both from food LCAs and transport packing/packaging LCAs is recommended.

Conclusions

For all three systems, optimization potentials regarding their environmental life cycle performance were identified. Wooden boxes (single use) and plastic crates (re-usable) show preferable environmental performance. The calibration of the system parameters, such as end-of-life treatment, showed environmental optimization potentials in all transport packaging systems. The assessment of the economic and the social dimensions in parallel is important in order to avoid trade-offs between the three sustainability dimensions. Merging economic and social aspects into a Life Cycle Assessment is becoming more and more important, and their integration into one model ensures a consistent modeling approach for a manageable effort.  相似文献   
962.

Purpose

To assess the diverse environmental impacts of land use, a standardization of quantifying land use elementary flows is needed in life cycle assessment (LCA). The purpose of this paper is to propose how to standardize the land use classification and how to regionalize land use elementary flows.

Materials and methods

In life cycle inventories, land occupation and transformation are elementary flows providing relevant information on the type and location of land use for land use impact assessment. To find a suitable land use classification system for LCA, existing global land cover classification systems and global approaches to define biogeographical regions are reviewed.

Results and discussion

A new multi-level classification of land use is presented. It consists of four levels of detail ranging from very general global land cover classes to more refined categories and very specific categories indicating land use intensities. Regionalization is built on five levels, first distinguishing between terrestrial, freshwater, and marine biomes and further specifying climatic regions, specific biomes, ecoregions and finally indicating the exact geo-referenced information of land use. Current land use inventories and impact assessment methods do not always match and hinder a comprehensive assessment of land use impact. A standardized definition of land use types and geographic location helps to overcome this gap and provides the opportunity to test the optimal resolution of land cover types and regionalization for each impact pathway.

Conclusions and recommendation

The presented approach provides the necessary flexibility to providers of inventories and developers of impact assessment methods. To simplify inventories and impact assessment methods of land use, we need to find archetypical situations across impact pathways, land use types and regions, and aggregate inventory entries and methods accordingly.
  相似文献   
963.
Flowery field margins and intersowing of crops with flowers are used as management practices to promote arthropod biodiversity as well as biocontrol agents. Positive effects of enhancement (in abundance and species richness) of hymenopteran parasitoids on control of Lepidoptera pests have previously been demonstrated. However, effects on predatory arthropods, which may also serve as pest control agents, remain unclear. In an experimental study in cabbage fields we tested how sown flower strips on field margins and intersowing with cornflower affected the species richness, abundance and community composition of ground beetles and spiders. Furthermore, we investigated whether effects of flower margins are dependent on the distance from the field margins. We found that field margins generally harboured higher species richness, whereas effects on abundance were weaker. Intersown cornflower had positive effects on spider and ground beetle abundance, but affected species richness only weakly. Our results do not provide evidence for effects of distance from the flowery field margins on predator richness or abundance. Species composition was strongly affected by the habitat management actions. We conclude that habitat management practices like flower strips on field margins and intersowing with flowers, which are primarily added to attract and enhance parasitoids for pest control, also benefit biodiversity conservation in spiders and ground beetles. They also positively affect the abundance of these primarily predatory taxa, which adds to the biocontrol potential of non-crop flowering plants.  相似文献   
964.
The human immunodeficiency virus type 1 (HIV-1) is an enveloped virus with a lipid bilayer that contains several glycoproteins that are anchored in, or closely associated with, the membrane surface. The envelope proteins have complex interactions with the lipids both on the host cells and on the target cells. The processes of budding from host cells and entry into target cells occur at sites on the plasma membrane, known as lipid rafts, that represent specialized regions that are rich in cholesterol and sphingolipids. Although the envelope glycoproteins are antigenic molecules that potentially might be used for development of broadly neutralizing antibodies in a vaccine to HIV-1, the development of such antibodies that have broad specificities against primary field isolates of virus has been largely thwarted to date by the ability of the envelope proteins to evade the immune system through various mechanisms. In this review, the interactions of HIV-1 with membrane lipids are summarized. Liposomes are commonly used as models for understanding interactions of proteins with membrane lipids; and liposomes have also been used both as carriers for vaccines, and as antigens for induction of antibodies to liposomal lipids. The possibility is proposed that liposomal lipids, or liposome-protein combinations, could be useful as antigens for inducing broadly neutralizing antibodies to HIV-1.  相似文献   
965.
Age-related macular degeneration (AMD) is a complex genetic disease, with many loci demonstrating appreciable attributable disease risk. Despite significant progress toward understanding the genetic and environmental etiology of AMD, identification of additional risk factors is necessary to fully appreciate and treat AMD pathology. In this study, we investigated copy number variants (CNVs) as potential AMD risk variants in a cohort of 400 AMD patients and 500 AMD-free controls ascertained at the University of Iowa. We used three publicly available copy number programs to analyze signal intensity data from Affymetrix GeneChip SNP Microarrays. CNVs were ranked based on prevalence in the disease cohort and absence from the control group; high interest CNVs were subsequently confirmed by qPCR. While we did not observe a single-locus "risk CNV" that could account for a major fraction of AMD, we identified several rare and overlapping CNVs containing or flanking compelling candidate genes such as NPHP1 and EFEMP1. These and other candidate genes highlighted by this study deserve further scrutiny as sources of genetic risk for AMD.  相似文献   
966.
Being of the most frequent causes of insomnia, which in the end leads to chronic fatigue, inadequate performance of daily activities, and serious disruption of quality of living, restless legs syndrome (RLS) is nowadays not only a serious medical problem but a socio-economical one as well. Prevalence of the disorder in general population is estimated at 5 to 15%. Family history is positive in over 50% of idiopathic RLS patients which points to genetic basis of the disorder. The characteristics of the secondary or acquired form of RLS are symptoms that start later in life as well as a rapid progression of the disease. On the other hand, idiopathic RLS more often starts at a younger age and the prognoses are better. Over twenty disorders and conditions are brought in connection with secondary RLS. Although the cause of primary RLS is still unknown, there is a strong connection between central metabolism of iron as well as dopamine levels and RLS manifestation. A differential diagnosis of RLS includes a wide specter of motor and sensory disorders. Diagnosis is based on clinical features and the history of disease. To correctly diagnose idiopathic RLS one must first eliminate secondary causes of RLS and then also exclude any disorders with clinical features that mimic those of RLS. It has been estimated that some 20 to 25% of patients need pharmacological therapy. Best initial therapy is the application of nonergot dopamine agonists. Anticonvulsants, benzodiazepines and opioides can be given to patients who are refractory to dopaminergic therapy, those suffering from RLS with emphasized painful sensory component and those with RLS connected with insomnia.  相似文献   
967.
968.
969.
Lahti JL  Lui BH  Beck SE  Lee SS  Ly DP  Longaker MT  Yang GP  Cochran JR 《FEBS letters》2011,585(8):1135-1139
Receptor tyrosine kinases (RTKs) regulate critical cell signaling pathways, yet the properties of their cognate ligands that influence receptor activation are not fully understood. There is great interest in parsing these complex ligand-receptor relationships using engineered proteins with altered binding properties. Here we focus on the interaction between two engineered epidermal growth factor (EGF) mutants and the EGF receptor (EGFR), a model member of the RTK superfamily. We found that EGF mutants with faster kinetic on-rates stimulate increased EGFR activation compared to wild-type EGF. These findings support previous predictions that faster association rates correlate with enhanced receptor activity.  相似文献   
970.
The eukaryotic cell cycle is regulated by multiple ubiquitin-mediated events, such as the timely destruction of cyclins and replication licensing factors. The histone H4 methyltransferase SET8 (Pr-Set7) is required for chromosome compaction in mitosis and for maintenance of genome integrity. In this study, we show that SET8 is targeted for degradation during S phase by the CRL4(CDT2) ubiquitin ligase in a proliferating cell nuclear antigen (PCNA)-dependent manner. SET8 degradation requires a conserved degron responsible for its interaction with PCNA and recruitment to chromatin where ubiquitylation occurs. Efficient degradation of SET8 at the onset of S phase is required for the regulation of chromatin compaction status and cell cycle progression. Moreover, the turnover of SET8 is accelerated after ultraviolet irradiation dependent on the CRL4(CDT2) ubiquitin ligase and PCNA. Removal of SET8 supports the modulation of chromatin structure after DNA damage. These results demonstrate a novel regulatory mechanism, linking for the first time the ubiquitin-proteasome system with rapid degradation of a histone methyltransferase to control cell proliferation.  相似文献   
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