Inclusion of uncertainty in the LCA comparison of different cherry tomato production scenarios

Purpose

Knowledge regarding environmental impacts of agricultural systems is required. Consideration of uncertainty in life cycle assessment (LCA) provides additional scientific information for decision making. The aims of this study were to compare the environmental impacts of different growing cherry tomato cultivation scenarios under Mediterranean conditions and to assess the uncertainty associated to the different agricultural production scenarios.

Materials and methods

The burdens associated to cherry tomato production were calculated and evaluated by the LCA methodology. The functional unit (FU) chosen for this study was the mass unit of 1 t of commercial loose cherry tomatoes. This study included the quantitative uncertainty analysis through Monte Carlo simulation. Three scenarios were considered: greenhouse (GH), screenhouse (SH), and open field (OF). The flows and processes of the product scenario were structured in several sections: structure, auxiliary equipment, fertilizers, crop management, pesticides, and waste management. Six midpoint impact categories were selected for their relevance: climate change, terrestrial acidification, marine eutrophication, metal depletion, and fossil depletion using the impact evaluation method Recipe Midpoint and ecotoxicity using USEtox.

Results and discussion

The structure, auxiliary equipment, and fertilizers produced the largest environmental impacts in cherry tomato production. The greatest impact in these stages was found in the manufacture and drawing of the steel structures, manufacture of perlite, the amount of HDPE plastics used, and the electricity consumed by the irrigation system and the manufacture and application of fertilizers. GH was the cropping scenario with the largest environmental impact in most categories (varying from 18 and 37% higher than SH and OF, respectively, in metal depletion, to 96% higher than SH and OF, in eutrophication). OF showed the highest uncertainty in ecotoxicity, with a bandwidth of 60 CTUe and a probability of 100 and 99.4% to be higher than GH and SH, respectively.

Conclusions

The LCA was used to improve the identification and evaluation of the environmental burdens for cherry tomato production in the Mediterranean area. This study demonstrates the significance of conducting uncertainty analyses for comparative LCAs used in comparative relative product environmental impacts.

     

Tales of the cryptic: unveiling more angiogenesis inhibitors

Over the past few years, there has been a dramatic increase in the identification of anti-angiogenic fragments from larger proteins with unrelated functions. These cryptic anti-angiogenic molecules are largely derived from matrix components such as collagen and fibronectin, as well as from circulating proteins and some intracellular proteins. Here, we discuss the relevance of these developments in terms of their physiological roles and possible therapeutic applications.     

Structural basis for the beta lactam resistance of PBP2a from methicillin-resistant Staphylococcus aureus

The multiple antibiotic resistance of methicillin-resistant strains of Staphylococcus aureus (MRSA) has become a major clinical problem worldwide. The key determinant of the broad-spectrum beta-lactam resistance in MRSA strains is the penicillin-binding protein 2a (PBP2a). Because of its low affinity for beta-lactams, PBP2a provides transpeptidase activity to allow cell wall synthesis at beta-lactam concentrations that inhibit the beta-lactam-sensitive PBPs normally produced by S. aureus. The crystal structure of a soluble derivative of PBP2a has been determined to 1.8 A resolution and provides the highest resolution structure for a high molecular mass PBP. Additionally, structures of the acyl-PBP complexes of PBP2a with nitrocefin, penicillin G and methicillin allow, for the first time, a comparison of an apo and acylated resistant PBP. An analysis of the PBP2a active site in these forms reveals the structural basis of its resistance and identifies features in newly developed beta-lactams that are likely important for high affinity binding.     

Differential gene expression during somatic embryogenesis in the maize (<Emphasis Type="Italic">Zea mays</Emphasis> L.) inbred line H99

Somatic embryogenesis is a complex developmental process that offers great potential for plant propagation. Although many studies have shown that the generation of embryonic cells from somatic cells is accompanied by the synthesis of RNA and DNA and by elevated enzymatic activity, the mechanism of the onset of somatic embryogenesis is not well understood. cDNA-amplified fragment length polymorphism analysis was used to evaluate the gene expression pattern in embryogenic and non-embryogenic of the inbred maize line H99 during the process of embryogenesis. We identified a total of 101 candidate genes associated with the formation of maize embryonic calli. Based on the sequence analysis, these genes included 53 functionally-annotated TDFs involved in such processes as energy production and conversion, cell division and signal transduction, suggesting that somatic embryogenesis undergoes a complex process. Two full-length cDNA sequences, encoding KHCP (kinesin heavy chain like protein) and TypA (tyrosine phosphorylation protein A), and partial sequences, encoding ARF-GEP (guanine nucleotide-exchange protein of ADP ribosylation factor) homologs, were isolated from embryonic calli of maize and named ZmKHCP, ZmTypA and ZmARF-GEP, respectively. Finally, the real-time qRT-PCR results showed that the expression levels of the three genes were significantly higher in the embryonic calli than the non-embryonic calli. Thus, this study provides important clues to understanding the induction of somatic embryogenesis in maize. The candidate genes associated with the formation of embryonic calli may offer additional insights into the mechanism of somatic embryogenesis, and further research on the three candidate genes may determine their role in increasing the rate of induction of embryonic calli, which may aid in the development of cultivars through transgenic breeding.     

Expression of ethylene response genes during persimmon fruit astringency removal

Thirteen ethylene signaling related genes were isolated and studied during ripening of non-astringent ‘Yangfeng’ and astringent ‘Mopan’ persimmon fruit. Some of these genes were characterized as ethylene responsive. Treatments, including ethylene and CO₂, had different effects on persimmon ripening, but overlapping roles in astringency removal, such as increasing the reduction in levels of soluble tannins. DkERS1, DkETR2, and DkERF8, may participate in persimmon fruit ripening and softening. The expression patterns of DkETR2, DkERF4, and DkERF5 had significant correlations with decreases in soluble tannins in ‘Mopan’ persimmon fruit, suggesting that these genes might be key components in persimmon fruit astringency removal and be the linkage between different treatments, while DkERF1 and DkERF6 may be specifically involved in CO₂ induced astringency removal. The possible roles of ethylene signaling genes in persimmon fruit astringency removal are discussed.     

Mimicking a p53‐MDM2 interaction based on a stable immunoglobulin‐like domain scaffold

Antibodies recognize protein targets with great affinity and specificity. However, posttranslational modifications and the presence of intrinsic disulfide‐bonds pose difficulties for their industrial use. The immunoglobulin fold is one of the most ubiquitous folds in nature and it is found in many proteins besides antibodies. An example of a protein family with an immunoglobulin‐like fold is the Cysteine Protease Inhibitors (ICP) family I42 of the MEROPs database for protease and protease inhibitors. Members of this protein family are thermostable and do not present internal disulfide bonds. Crystal structures of several ICPs indicate that they resemble the Ig‐like domain of the human T cell co‐receptor CD8α As ICPs present 2 flexible recognition loops that vary accordingly to their targeted protease, we hypothesize that members of this protein family would be ideal to design peptide aptamers that mimic protein‐protein interactions. Herein, we use an ICP variant from Entamoeba histolytica (EhICP1) to mimic the interaction between p53 and MDM2. We found that a 13 amino‐acid peptide derived from p53 can be introduced in 2 variable loops (DE, FG) but not the third (BC). Chimeric EhICP1‐p53 form a stable complex with MDM2 at a micromolar range. Crystal structure of the EhICP1‐p53(FG)‐loop variant in complex with MDM2 reveals a swapping subdomain between 2 chimeric molecules, however, the p53 peptide interacts with MDM2 as in previous crystal structures. The structural details of the EhICP1‐p53(FG) interaction with MDM2 resemble the interaction between an antibody and MDM2.     

Interpenetrating Triphase Cobalt‐Based Nanocomposites as Efficient Bifunctional Oxygen Electrocatalysts for Long‐Lasting Rechargeable Zn–Air Batteries

Rational construction of atomic‐scale interfaces in multiphase nanocomposites is an intriguing and challenging approach to developing advanced catalysts for both oxygen reduction (ORR) and evolution reactions (OER). Herein, a hybrid of interpenetrating metallic Co and spinel Co₃O₄ “Janus” nanoparticles stitched in porous graphitized shells (Co/Co₃O₄@PGS) is synthesized via ionic exchange and redox between Co²⁺ and 2D metal–organic‐framework nanosheets. This strategy is proven to effectively establish highways for the transfer of electrons and reactants within the hybrid through interfacial engineering. Specifically, the phase interpenetration of mixed Co species and encapsulating porous graphitized shells provides an optimal charge/mass transport environment. Furthermore, the defect‐rich interfaces act as atomic‐traps to achieve exceptional adsorption capability for oxygen reactants. Finally, robust coupling between Co and N through intimate covalent bonds prohibits the detachment of nanoparticles. As a result, Co/Co₃O₄@PGS outperforms state‐of‐the‐art noble‐metal catalysts with a positive half‐wave potential of 0.89 V for ORR and a low potential of 1.58 V at 10 mA cm^?2 for OER. In a practical demonstration, ultrastable cyclability with a record lifetime of over 800 h at 10 mA cm^?2 is achieved by Zn–air batteries with Co/Co₃O₄@PGS within the rechargeable air electrode.     

A computational insight into binding modes of inhibitors XD29, XD35, and XD28 to bromodomain-containing protein 4 based on molecular dynamics simulations

In the current work, conformational changes of bromodomain-containing protein 4 (1) (BRD4-1) induced by bindings of inhibitors XD29 (57G), XD35 (57F), and XD28 (L28) were investigated using molecular dynamics (MD) simulations and principal component analysis. The results demonstrate that inhibitor bindings produce significant effect on the motion of ZA loop in BRD4-1. Moreover, to further study binding modes of three inhibitors to BRD4-1, binding free energies of inhibitors to BRD4-1 were also calculated using molecular mechanics Poisson-Boltzmann surface area (MM-PBSA) method. The results indicate that van der Waals interactions are main factors to modulate inhibitor bindings. Energy decomposition and hydrogen bond analysis demonstrate that residues Pro82, Leu92, Asn140, and Ile146 play important roles in binding processes of inhibitors to BRD4-1. This study is not only helpful for better understanding function and internal dynamics of BRD4-1, but also can provide a theoretical basis for rational designs of effective anticancer drugs targeting BRD4-1.     

Haploid induction via unfertilized ovary culture in watermelon

Unfertilized ovary culture constitutes an effective method for haploid breeding and can greatly shorten the breeding time. This method has been successfully used for breeding in many species, but reports of this method for breeding watermelon are scarce. Therefore, we performed an experiment to induce haploid plantlets. We evaluated the effects of several important factors on unfertilized ovary cultures of watermelon, including genotype, medium, the duration of induction and the development stage of the ovaries. The results revealed that the genotype of donor plants was a key factor for in vitro gynogenesis. The induction rate of eight watermelon cultivars varied from 0.00 to 15.14 ELSs per100 ovary slices. The most effective induction medium and maturation medium were MS medium supplemented with 3 mg L^??1 2,4-D, 2 mg L^??1 BAP, 0.5 mg L^?1 NAA and MS supplemented with 0.8 mg L^??1 BAP and 0.2 mg L^??1 NAA, respectively. The duration of induction significantly influenced ELS formation. The optimum duration was 13 days, and unfertilized ovaries collected at anthesis had the higher induction rate. We obtained more than 100 plantlets and used chromosome counting and flow cytometry to determine the ploidy levels of 50 of them, among which 48 were haploid and 2 were diploid. Our results demonstrated that in vitro gynogenesis can be induced in watermelon by unfertilized ovaries culture.     

Lymphocyte activation and serine-esterase induction following recombinant interleukin-2 infusion for lymphomas and acute leukaemias

Summary C57BL mice inoculated with radiation leukemia virus (RadLV) develop preleukemic cells long before the onset of leukemia. These cells are potentially immunogenic but fail to elicit an immune response in the host because of the appearance of virus-specific suppressor T cells. We have studied the effect of polysaccharide K (PSK) on the generation of RadLV-specific cell-mediated immune responses in vitro. Long-term exposure to PSK in culture potentiated the ability of immunized T cells to respond to a RadLV-induced lymphoma. It also abrogated the suppressive activity of suppressor T cells and simultaneously boosted the ability of reactive T cells to respond. The dual immunostimulating activity of PSK resulted in the generation of T cytotoxic lymphocytes that could lyse lymphoma cells in vitro. The results suggest that PSK could be used as a prophylactic immune response modifier in preleukemia.