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Metal materials undergo severe corrosion in eutrophic environments. The effect of DO decay stimulated by high concentrations of nitrogen and phosphorus pollutants on microorganisms leads to the coupling of electrochemical and microbial corrosion processes. However, there are few studies on microbial corrosion mechanisms in eutrophic environments. This article discusses the corrosive factors of marine eutrophication, summarizes the impact of marine eutrophication on microbial corrosion and the potential mechanisms, including aerobic biofilm corrosion, aerobic & anaerobic mixed biofilm corrosion, and anaerobic microbial electron transfer corrosion, and expounds on the research methods for microbial corrosion of materials serving in estuarine areas prone to pollution. Microbial prevention and control, such as nutrient restriction and microbial interspecies competition, are of research value in the field of green protection. Microbial corrosion mechanisms studies in marine eutrophication environments are significant for environment monitor development, water intake and algae control technologies, and corrosion protection in polluted environments., Competing Interests: Declaration of competing interest The authors declare that there are not much commercial or financial relationships that could be related to a potential conflict of interest in this review paper., (Crown Copyright © 2024. Published by Elsevier Ltd. All rights reserved.)

Volatile methylsiloxanes (VMSs) earned serious concerns due to their detection and toxicities after their release to the environments. They were also detected in rivers around the globe, but their distribution remained to be explored in larger rivers with longer length, higher water volume and wider watershed. In the present study, 8 cyclic VMSs (cVMSs) and 7 linear ones (lVMSs) were investigated in 42 water samples (27 surface water (including 7 drinking source water) and 15 wastewater) from the Yangtze River Basin, China. Results showed that VMSs were detected in all sampling sites. In surface water, the concentrations of total cVMSs ranged from 17.3 to 4.57 × 10 3  ng/L, while those of lVMSs ranged from 1.72 to 81.6 ng/L. In wastewater, the total concentrations of cVMSs and lVMSs showed ranges of 17.6-1.66 × 10 3  ng/L and 2.59-252 ng/L, respectively. Apparently, cVMSs showed significantly higher concentrations than lVMSs. The concentrations of cVMSs followed an order of lower > upper > middle reaches, while those of lVMSs did not show clear distribution patterns. Among cVMSs, those with less Si numbers were dominant, while those with more Si numbers were dominant in lVMSs. Notably, the VMSs were also detected in 7 surface waters that served as drinking source waters, which earned them further concerns. In addition, the VMSs in surface water showed positive correlation with those in wastewater, which led to necessity in management on industrial emissions in the future., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Microbiologically influenced corrosion (MIC) is a complicated process that happens ubiquitously and quietly in many fields. As a useful nutritional ingredient in microbial culture media, yeast extract (YE) is a routinely added in the MIC field. However, how the YE participated in MIC is not fully clarified. In the present work, the effect of YE on the growth of sulfate reducing prokaryotes (SRP) Desulfovibrio bizertensis SY-1 and corrosion behavior of X70 pipeline steel were studied. It was found that the weight loss of steel coupons in sterile media was doubled when YE was removed from culture media. However, in the SRP assays without YE the number of planktonic cells decreased, but the attachment of bacteria on steel surfaces was enhanced significantly. Besides, the corrosion rate of steel in SRP assays increased fourfold after removing YE from culture media. MIC was not determined for assays with planktonic SRP but only for biofilm assays. The results confirm the effect of YE on D. bizertensis SY-1 growth and also the inhibitory role of YE on MIC., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Seasonal ice cover plays a crucial role in shaping the physical characteristics of lakes in cold and arid regions. Moreover, the ice significantly affects the level and quality of dissolved organic matter (DOM) in the water column. We utilized spectroscopy and mass spectrometry to analyze the molecular composition and distribution of DOM in ice cores and under-ice water in Daihai Lake. We identified the main environmental factors affecting DOM migration through structural equation modelling (SEM). The freezing process created a repulsive effect on DOM, with water samples demonstrating a greater DOM content than ice. The dominant part of the DOM in the ice cores was mainly comprised of protein-like materials (71.45 %), whereas water consisted of humus-like materials (54.81 %). The average molecular weight of the ice cover DOM (m/z = 396.77) was smaller than in the under-ice water (m/z = 405.42). While low-molecular and low-aromatic protein-like material tended to be trapped in the ice layer during ice formation, large-molecular and highly aromatic humic substances were more easily expelled into the water. Interestingly, condensed aromatic hydrocarbons were found to occur less frequently in the ice phase (11 %) compared to the aqueous phase (13 %). Both the lipid and protein/aliphatic compound structures exhibited slightly higher ratios in the ice (6 % and 8 %, respectively) than in water (1 % and 5 %, respectively). SEM between the ice cover environment and DOM indicated that the ice can influence the distribution pattern of DOM through the regulation of internal solute factors and other chemicals. The nature of the DOM and the rate of ice growth also play critical roles in determining the distribution mechanism of DOM for ice and water. The pollutant distribution characteristics and migration patterns between ice and water are essential for comprehending environmental water pollution and promoting pollution management and protection measures in cold region lakes., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Endowing fluorescent pH sensors with large Stokes shifts promises to resolve interferential background fluorescence in practice, and yet few such method has been reported, owing to lack of luminescent materials with large Stokes shifts used in fluorescent sensors. Herein, we elaborately designed NaGdF 4 :Ce@NaGdF 4 :Nd@NaYF 4 :Eu core-double shells (CDS) lanthanide-doped fluoride nanoparticles (LFNPs), employing Gd 3+ -mediated energy migration and interfacial energy transfer to realize intense red and NIR emissions under 254 nm irradiation, and pseudo-Stokes shifts of which reached up to striking 361 nm and 610 nm, respectively. The CDS LFNPs collaborated with absorption-based pH indicator bromocresol green to from a novel fluorescent sensor film, and employing low-cost dual chip RGB-NIR camera to precisely record luminescence signals. On the basis of inner-filter effects, this senor system enabled accurate ratiometric read-out of pH value ranging from 5 to 6 (pK a ± 0.5), according to intensity ratios of pH-sensitive red emissions and referenced NIR emissions, avoiding common errors (e.g., fluctuant light sources). Notably, the large pseudo-Stokes shifts allowed red and NIR emissions far from the interfering background fluorescence possessing relatively small Stokes shifts, ensuring elevated signal-to-noise ratio and accurate pH determination. Therefore, the devised pH sensor system based on the CDS LFNPs exhibited sufficient accuracy in autofluorescent real samples (e.g., algae, serum), revealing a novel way of employing large pseudo-Stokes shifts to realize the background-free pH measurement and 2D imaging., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Deterioration corrosion occurs between the external surface of oil pipelines and aerobic oil-degrading microorganisms in oil fields. Microorganisms with aerobic oil pollution remediation capabilities may catalyze more serious anaerobic microbial corrosion due to the carbon source supply. In this study, Acinetobacter soli strains were isolated from oil-contaminated environments, and their role in the deterioration corrosion behavior of X70 steel in an oil-water environment was investigated using the EDS multipoint scanning method. The presence of oil controls the deposition of carbon and phosphorus and diffusion of oxygen, leading to significant adhesion attraction and initial growth inhibition of biofilm on the metal surface. A. soli facilitates oxygen transfer and iron ion dissolution, thereby accelerating the pitting corrosion of X70 steel. This corrosion of the X70 steel, in turn, further accelerates the microbial degradation of oil, inhibiting the appearance of calcareous scale in the later stage of corrosion. The corrosion of X70 steel is influenced by microbial degradation, and the specific corrosion behaviors are related to the activity of A. soli in the petroleum environment. This study sheds light on the corrosion mechanisms of X70 steel by A. soli at different stages, providing insights into the interactions between microorganisms, oil pollution, and metal corrosion in oil fields., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier B.V.)

Background: Longitudinally conserved microbe-microbe interactions may provide insights to understand the complex dynamic system of early-life gut microbiota among preterm infants., Objectives: We aimed to profile the covarying network of gut microbiota among preterm infants and investigate its potential influence on host growth (2-5 y)., Methods: We collected time-series stool samples (n = 717 from children and n = 116 from mothers) among 51 preterm and 51 full-term infants from birth up to 5 y of age and among 53 mothers. The included infants underwent time-series measurements of early-life gut microbiota (0-5 y) and growth (2-5 y) from June 2014 to April 2017. The covarying taxa that exhibited consistent covariation from day 1 to year 5 were defined as conserved features in the development of gut microbiota. Childrens' height-for-age z score (HAZ) and weight-for-age z score were calculated according to World Health Organization Child Growth Standards., Results: We observed distinct dynamic patterns of both microbial alpha and beta diversity comparing preterm infants with full-term controls during the very early stage (<3 mo). Moreover, we identified a covarying network containing 10 taxa as a conserved gut microbial feature of these preterm infants from birth to 5 y old. This covarying network was distinctive between preterm and full-term infants before 3 mo of age (P < 0.001) and tended to be similar as the infants grew up. Several covarying taxa of the network during early life (<3 mo) were associated with childhood growth (2-5 y) (eg, Clostridium&#95;sensu&#95;stricto&#95;1 with HAZ, β = -0.32, q < 0.01), and the human milk feeding duration was a main modulating factor., Conclusions: Preterm born children possess conserved and distinct covarying microbiota during very early life, which may have a profound influence on their growth later in life. This trial was registered at clinicaltrials.gov as NCT03373721., (Copyright © 2023 American Society for Nutrition. Published by Elsevier Inc. All rights reserved.)

Wound healing from bacterial infections is one of the major challenges in the biomedical field. The traditional single administration methods are usually accompanied with side effects or unsatisfactory efficacy. Herein, we design dynamically evolving antibacterial and repair-promoting nanocomposites (NCs) by in situ self-assembling of zeolitic imidazolate framework-8 (ZIF-8) on the surface of barium titanate (BTO), and further loading with a small amount of ciprofloxacin (CIP). The new strategy of combining pH-stimulated drug delivery and ultrasound-controlled sonodyamics has the potential to dynamically evolve in infected wound sites, offering a multifunctional therapy. In vitro study demonstrates that the enhancement generation of reactive oxygen species through the sonodynamic process due to the heterostructures and a small amount of CIP released in an acidic environment are synergistically antibacterial, and the inhibition rate was >99.9%. In addition, reduced sonodynamic effect and Zn 2+ generated along with the gradual degradation of ZIF-8 simultanously promote cell migration and tissue regeneration. The in vivo study of full-thickness skin wounds in mouse models demonstrate a healing rate of 99.3% could be achieved under the treatment of BTO@ZIF-8/CIP NCs. This work provides a useful improvement in rational design of multi-stimulus-responsive nanomaterials for wound healing. STATEMENT OF SIGNIFICANCE: A novel piezoelectric nanocomposite was proposed to realize sonodynamic therapy and pH-stimulated drug releasing simultaneously in wound healing treatment. The dynamically evolving structure of the piezoelectric nanocomposite in acidic microenvironment has been theoretically and experimentally verified to contribute to a continuous variation of sonodymanic strength, which accompanied with the gradual releasing of drug and biocompatible Zn 2+ effectively balanced antibacterial and repair-promoting effects. Both of the in vitro and in vivo study demonstrated that the strategy could significantly accelerate wound healing, inspiring researchers to optimize the design of multi-stimulus-responsive nanomaterials for various applications in biomedical and biomaterial fields., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.)

Renal fibrosis is the ultimate presentation of chronic kidney disease, which progresses to end-stage renal disease. Hydroxychloroquine (HCQ) has been adapted for the treatment of autoimmune diseases; however, the potential mechanism underlying the role of HCQ in renal fibrosis remains unclear. C57BL/6 J mice were randomly divided into three groups (sham group, UUO group, and UUO + HCQ group (20 mg/kg)). HE and Masson staining were performed to assess kidney tissue damage and fibrosis, and western blotting was performed to assess the expression of epithelial-mesenchymal transition (EMT), extracellular matrix (ECM), PI3K/AKT, and NF-κB-related proteins. PCR and TUNEL were adopted to detect inflammatory factors and cell apoptosis. HK-2 cells treated with TGF-β1 were used for the in vitro experiments. HCQ may potentially have therapeutic effects on renal fibrosis mediated through 122 target genes, and the Kyoto Encyclopedia of Genes and Genomes pathways of these genes were enriched for PI3K/AKT signaling based on network pharmacology. UUO mice that received HCQ demonstrated significantly less tubular damage than the UUO mice. HCQ treatment additionally blunted EMT in UUO kidneys and TGF-β1-treated renal tubular epithelial cells, and alleviated ECM deposition in kidney tissue. Furthermore, HCQ treatment reduced UUO-induced inflammation and apoptosis. Mechanistically, HCQ treatment suppressed the activation of the PI3K/Akt and NF-kB pathways. This study demonstrated that HCQ ameliorated renal fibrosis by inhibiting the PI3K/AKT and NF-κB signaling pathways to attenuate inflammatory factors and the apoptotic function of renal tubular epithelial cells, thus providing renewed theoretical evidence for HCQ treatment of renal fibrosis., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)

Biocides are often used to mitigate the microbially influenced corrosion (MIC) of construction materials in many fields. To study the effect of inadequate dosing of non-oxidizing biocide tetrakis (hydroxymethyl) phosphonium sulfate (THPS) on corrosion of pipeline steel caused by microorganisms, a novel marine isolate Desulfovibrio hontreensis SY-21 was selected as a test microorganism. Weight loss rate determination, morphological analyses, and corrosion product analyses combined with electrochemical measurements were performed to investigate the influence of THPS on the MIC of X70 pipeline steel. The responses of sessile and planktonic cells of D. hontreensis to THPS were also studied. Results showed that D. hontreensis cells could significantly promote steel corrosion and induce local corrosion pits. With a THPS addition within the tolerance range of D. hontreensis for the biocide, MIC of the steel was further promoted by 65%. The growth of planktonic cells was inhibited by the biocide, but the number of biofilm cells was significantly increased. This study revealed that THPS concentrations within a specific range increased the corrosive effect of the presence of D. hontreensis by promoting the growth of sessile cells and biofilm formation. Therefore, the use of the biocide in practical applications needs to be properly considered and managed., (Copyright © 2022 Elsevier B.V. All rights reserved.)

A kind of organic-inorganic hybrid silica nanoparticles loaded with 1,8-naphthalimide borate ester (NIB@SiO 2 ) was used to detect trace hydrogen peroxide (H 2 O 2 ) vapor via turn-off mechanism. The detailed studies showed that utilizing silica nanoparticles can improve the adsorption properties and hydrophilicity of the sensing film, accelerate the deboronation reaction between the sensing material and H 2 O 2, and then shorten the response time successively, which is always the disturbing challenge for this deboronation-type fluorescent probe to H 2 O 2 vapor. The fluorescence of NIB@SiO 2 film was quenched greatly under H 2 O 2 saturated vapor within 5 s at room temperature and limit of detection (LOD) was estimated to be 184 ppt, which are among the best reported results. Thus, this study provides an ultrafast and highly sensitive organic-inorganic hybrid fluorescent probe to H 2 O 2 vapor, moreover, a new design strategy for promising H 2 O 2 fluorescent probe is revealed., (Copyright © 2021 Elsevier B.V. All rights reserved.)

The detections of explosives and chemical warfare agents (CWAs) are always important for global security. In this study, a simple donor (D)- acceptor (A) type small organic fluorescent triazole-based molecule (T1) is reported. T1 is composed of a central 4H-1, 2, 4-triazole (TAZ) "core" and three external triphenylamine (TPA) groups. Its spin-coating films can realize the multi-analyte fluorescent prober to detect DNT (2, 4-dinitrotoluene), hydrogen peroxide (H 2 O 2 , the substitute for triacetone triperoxide (TATP)) and diethylchlorophosphate (DCP, the substitute for Sarin) vapors. Additionally, the combination of the triple sensing mechanism in the different channels affords three distinct sets of output-signal responses, these three hazardous compounds could be identified rapidly with high sensitivity and selectivity: fluorescence turn-off response to DNT, fluorescence turn-on response to H 2 O 2 and fluorometric-colorimetric dual-channel response to DCP. T1 fluorescent probe is highly advantageous for concurrently monitoring various hazardous target substances and simultaneously possessing the desirable sensitivity and selectivity, excellent reusability. Hereby, this study provides a prototype method to build novel multifunctional fluorescent probes to explosives and CWAs., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Exosomes carrying abundant information have aroused great interest as effective biomarkers in liquid biopsy and are therefore ideal candidates for the early diagnosis of cancer and treatment monitoring. Herein, we developed a sensitive electrochemical biosensor using in situ generation of Fe₄[Fe(CN) 6 ]₃ (Prussian Blue) on the surface of Ti 3 C 2 MXene (two-dimensional transition-metal carbides) as hybrid nanoprobes (PB-MXene) for the detection of exosomes and their surface protein. A CD63 aptamer-modified poly(amidoamine) (PAMAM)-Au NP electrode interface was fabricated that can specifically bind with CD63 protein on the exosomes derived from OVCAR cells. In addition, the CD63-modified Ti 3 C 2 MXene was used as a nanocarrier to accommodate numerous aptamers and was adsorbed on the exosomes. The Ti 3 C 2 MXene can realize the in situ generation and high-efficiency loading of PB and further amplify the electrochemical signal at a low potential, thus avoiding the interference of the electrochemical active species. The dual amplification effect enables highly selective and sensitive electrochemical detection of exosomes. The limit of detection (LOD) was 229 particles μL -1 with a linear range from 5 × 10 2 particles μL -1 to 5 × 10 5 particles μL -1 . An electrochemical biosensor can detect exosomes secreted by various cancer cells such as HeLa, OVCAR and BT474, and shows a high specificity even in serum samples, thus demonstrating its great potential in the application of clinical diagnostics. This proposed electrochemical biosensor provides a facile and efficient tool for the early diagnosis of cancers., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Background: The experience of older women during breast cancer treatment is insufficiently described by quantitative studies. This study aimed to systematically review qualitative data describing factors that influence older women's (≥65 years old) experience with breast cancer treatment., Methods: A systematic review was performed in accordance with Preferred Reporting Items for Systematic Review and Meta-analysis Protocols (PRISMA) principles. MEDLINE, CINAHL, PsycINFO, and EMBASE were searched (inception - 2020). Quality assessment of essential item reporting was performed using the Standards for Reporting Qualitative Research (SRQR) criteria. Common ideas were coded, thematically organized, and synthesized within a theoretical framework., Results: Of 7,773 studies identified, twelve were included. The median SRQR score was 13.4 (range 11.3-15.9) (maximum score: 21). Data synthesis revealed that older women experienced breast cancer as a journey with challenges during each phase. During diagnosis, they delayed seeking medical help despite symptoms. Age and experience gave them perspective on the impact of their diagnosis. During decision-making, preconceptions and personal values determined choices. In the treatment phase, women experienced medical and social barriers to care. During the post-treatment phase, many experienced treatment adverse effects, but could move on or compartmentalize as coping mechanisms., Conclusion: Older women with breast cancer have unique challenges specific to each phase of their treatment journey. Older women may benefit from proactive treatment discussions with health care providers to address their specific needs, individualize care, and assist with cancer care navigation., Competing Interests: Declaration of competing interest None., (Copyright © 2020 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Drought stress is considered a critical environmental factor that negatively affects wheat growth and development, which causes considerable losses in wheat yields worldwide. More recently, numerous microRNAs (miRNAs) have been found to be involved in wheat responses to drought stresses. However, there is little information regarding the effects of He-Ne laser irradiation on the expression traits of miRNAs and their targets in wheat seedlings exposed to drought stress. In the current study, therefore, a combination of physiological and molecular approaches was used to assess the effect of He-Ne laser irradiation on the expression of miRNAs and their targets in wheat seedlings exposed to drought stress. Our results demonstrated that drought stress significantly reduced plant height, root length, shoot and root fresh weight, relative water content, the expression level and activity of superoxide dismutase (SOD), enhanced malondialdehyde (MDA) concentration in the wheat seedlings. However, He-Ne laser irradiation significantly enhanced the activities of SOD, ascorbate peroxidase (APX), peroxidase (POD) and relative water content, and reduced MDA concentration of seedlings by regulating gene expression for SOD, POD, APX. In addition, in comparison with drought stress alone, miR160, miR164 and miR398 transcripts were down-regulated, and expression levels of its targets auxin response factor (ARF22), NAC domain transcription factor and Cu/Zn superoxide dismutases (CSD) were up-regulated in He-Ne laser irradiated seedlings exposed to drought stress. These results suggested that He-Ne laser irradiation could possible protection of drought stress, at least partially, by increasing the transcript levels and activities of SOD, POD and APX, and decreasing the transcript levels of miR160, miR164 and miR398. To the best of our knowledge, this is the first study to present biochemical and molecular evidence supporting the effect of He-Ne laser irradiation on the alleviation of drought stress in wheat seedlings mediated by miRNA expression., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Dioscin shows active effects against renal ischemia/reperfusion injury and lipopolysaccharide-induced inflammatory kidney injury, however, little is known concerning the role of it on doxorubicin (Dox)-induced nephrotoxicity. In the present study, in vivo test of Dox-induced nephrotoxicity in rats and in vitro model in NRK-52E cells were developed. The results showed that dioscin significantly attenuated cell injury, obviously reduced ROS level in vitro, and markedly decreased the levels of BUN, Cr, MDA, and notably increased the levels of SOD, GSH and GSH-Px in rats. Mechanistic studies showed that dioscin significantly increased the levels of p-AMPKα, Nrf2, HO-1 and GST by activation of FXR against oxidative stress. In addition, dioscin suppressed the nuclear translocation of NF-κB and HMGB1, and subsequently decreased the mRNA levels of IL-1β, IL-6, and TNF-α against inflammation. These results were further validated by knockdown of FXR using siRNA silencing, and abrogation of FXR using NDB (a FXR inhibitor) in NRK-52E cells, and the results suggested that the protective effect of dioscin against Dox- induced nephrotoxicity via adjusting FXR-mediated signal to suppress oxidative stress and inflammation. In addition, molecular docking assay showed that dioscin directly targeted with FXR through competing with Helix12 (H12) by hydrogen bonding, hydrophobic effect and electrostatic interactions. In a word, our data showed that dioscin is a novel and potent FXR agonist to suppress inflammation and oxidative stress against Dox-induced nephrotoxicity., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Camptothecin, as an antitumor drug, has shown significant antitumor activity against various cancers through the inhibition of topoisomerase I. However, its poor solubility severely limits the clinical applications. Here, we report a camptothecin supramolecular vesicle based on the host-guest interactions, which can uniformly disperse camptothecin into water and greatly enhance camptothecin aqueous solubility. The camptothecin vesicles were identified by transmission electron microscopy (TEM), scanning electron microscopy (SEM), and dynamic light scattering (DLS). X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), UV-vis spectrum, 1H NMR and 2D NMR ROESY were further employed to study the formation mechanism of the vesicles. Furthermore, camptothecin could be controllably released when the competitive guests were added into the vesicles system. Finally, the camptothecin vesicles in aqueous solution exhibited comparable antitumor activity in vitro as natural camptothecin in DMSO to HeLa cells under the same conditions., (Copyright © 2014 Elsevier Ltd. All rights reserved.)