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Understanding the complex network response to nodes failure is important to protect them and guarantee their functioning. Most existing studies considered binary networks where the intensity (weight) of the links is not accounted for. However, in real world networks the intensity of the links widely differ so that a realistic description of complex networks is only possible if the heterogeneity present in edge weights is taken into account. Further, the vast majority of the existing studies investigates the efficacy of the attack strategies when all the nodes are removed. Despite it is important to study the network behavior in such a circumstance, real-world networks are more likely to experience local failures involving a small amount of nodes with a decrease in the system functioning not causing an overall collapse. This is the case of crossroad closing in complex road networks. For this reason it is interesting to investigate the networks response focusing to small node removals. In this paper we analyze the response of the real-world road networks of Beijing, the capital of China, to the removal of 1 and 2 nodes and accounting the weighted structure of the network. We use both classic binary node properties and network functioning measurement, introduced a weighted rank for node importance (node strength or page rank), and used a measurement for network functioning that accounts for the weight of the links (weighted efficiency). We find that the weighted node attack strategy Str (i.e. strength attack), which removes nodes according to their strength, is the most efficient to blemish the system when evaluating the damage with a weighted efficiency. Differently, betweenness attack strategy Bet , which removes nodes according to their centrality is the most efficient when using the binary efficiency to compute the network damage. These results indicate that adopting weighted or binary efficiency to measure networks functioning changed the efficacy of the attack strategies to damage the system. Last, we found a non-negligible fraction of random removals to be more efficient than the attack strategies; given that the main goal of the attack strategies is to individuate important nodes in the system, i.e. nodes which removal triggers highest damage, our results would indicate how in order to find the most important nodes may be more efficient to simulate an higher number of random nodes removal. [ABSTRACT FROM AUTHOR]

Reverse Electrodialysis (RED) in a closed-loop arrangement is a viable way to convert low-grade heat into electric power. The present work experimentally investigates the use of pure salt- and equimolar two salts-water solutions as feeds in a lab-scale RED unit. RED performances were analysed in terms of Open Circuit Voltage (OCV), stack resistance and corrected power density. The pure salts and the mixtures employed were chosen via a computational analysis. Effect of feed solution velocity and concentration was investigated. Results concerning the pure salt-water experiments show that NH 4 Cl is the most performing salt in the concentration range probed, while higher power density values are expected with the use of LiCl at larger concentrations. As regards the salt binary mixtures, in some cases, the measured stack electrical resistance was found lower than both the two values measured for the corresponding pure salts, thus resulting into higher power density values for the mixtures. This surprising experimental evidence suggests that it is possible to increase the power produced by a conventional RED unit by adding an equivalent molar quantity of another suitable salt. Finally, among the mixtures tested, the NH 4 Cl-LiCl mixture appears as the most promising, thanks to the combination of the favorable properties of these two salts. [ABSTRACT FROM AUTHOR]

Coastal vulnerability is a spatial concept that identifies people and places that are susceptible to disturbances resulting from coastal hazards. Hazards in the coastal environment, such as coastal storms and erosion, pose significant threats to coastal physical, economic, and social systems. The theory of vulnerability has been an evolving idea over the past hundred years. In recent decades, improved technology and high-profile disaster events, has caused an increase in publications in the coastal hazards field. Modern approaches to understanding coastal vulnerability examine the complex systems that determine the spatial distribution of hazards, risks, and exposure. Consensus among today’s researchers shows that coastal vulnerability is geographically dependent and requires place based investigations. This review examines over 200 coastal vulnerability related works. Through this extensive literature review, this research describes the evolution of vulnerability concepts, and the modern definition of vulnerability with the goal of providing a well-informed body of knowledge to be used in the advancement of resilience and increased sustainability in coastal areas. [ABSTRACT FROM AUTHOR]

Regulated deficit irrigation, which is a common practice to cope with water scarcity, can impact plant-aphid interactions, and possibly lead to a reduction in the use of pesticides. To test the possible effect of water restriction on the apple tree-rosy apple aphid ( Malus domestica-Dysaphis plantaginea ) system, we performed a factorial experiment with two levels of water supply and two genotypes on artificially infested trees. Plant growth and aphid abundance were characterised during the entire infestation period at two scales of analysis: the apical shoot scale and the tree scale, and additional measures were performed to evaluate plant water status. Aphid abundance increased with plant vegetative growth at both scales of analysis, which is consistent with the Plant Vigor Hypothesis (i.e. with the fact that most of the phloem feeders prefer fast growing plants). At the tree scale, aphid abundance was lower on trees that underwent water restriction, but at the shoot scale, aphid abundance responded differently to water restriction depending on the tree genotype. Water restriction modified the relationship between aphid abundance and growth, thus indicating that host suitability for aphids was affected by different plant variables susceptible to water stress, among which growth. The different response patterns at the two scales of analysis highlight the importance of scale choice in the study of plant-insect interactions. [ABSTRACT FROM AUTHOR]

A Reverse ElectroDialysis Heat Engine (REDHE) system operating with “thermolytic” ammonium hydrogen-carbonate (NH 4 HCO 3 ) aqueous solutions as working fluids is studied. The engine is constituted by (i) a RED unit to produce electric power by mixing the solutions at different salinity and (ii) a thermally-driven regeneration unit including a stripping and an absorption column to restore the initial salinity gradient thus closing the cycle. In the present work only the RED unit and the stripping column are taken into account. In particular, a simplified integrated process model for the whole cycle was developed: it consists of (i) a lumped parameter model for the RED unit validated with experimental data and (ii) a model developed via a process simulator to assess the thermal duty of the stripping column. The effect of operating conditions as solution concentrations and velocities was investigated by a sensitivity analysis. Under the best conditions (among those investigated), a power density of about 9 W/m 2 of cell pair was predicted for the RED unit, and a maximum exergetic efficiency of about 22% was found for the whole cycle. A preliminary economic analysis of the process is also provided. [ABSTRACT FROM AUTHOR]

In bovine, intracytoplasmic sperm injection (ICSI) remains inefficient partially due to low levels of sperm decondensation. The aim of this study was to determine whether the injection of normal size sperm pretreated with heparin (Hep) and l -glutathione (GSH), the use of sex-sorted sperm, the double round of sperm freezing/thawing (re frozen), or the combination of these approaches can improve sperm decondensation and embryo development after ICSI in cattle. Cleavage and blastocyst rates were evaluated on days 2 and 7 post ICSI. Quality of ICSI blastocysts was analyzed by the relative expression of four genes by qPCR and the DNA fragmentation index by TUNEL assay. For all assays, semen samples were co-incubated with pCX- EGFP 50 ng/μl before ICSI. GFP expression, which can be detected by fluorescence microscopy, was used as a tool to estimate the success of sperm decondensation after ICSI. The use of normal size sperm pretreated with 80 μM Hep-15 mM GSH for 20 h (Hep-GSH) increased cleavage, blastocyst and EGFP + blastocysts rates (60.8, 19.4 and 61.9%) compared to control ICSI (35, 4.9 and 20%) (p < 0.05). Moreover, HMGN1, GLUT5, AQP3 and POU5F1 transcription levels did not differ between ICSI Hep-GSH and IVF embryos. The use of sex-sorted sperm (X, Y) improved cleavage rates and EGFP expression at day 4 (83 and 30.2% for ICSI Y and 83.2 and 31.7% for ICSI X) compared to non-sorted group (50.9 and 15.1%), not showing differences at the blastocyst stage. Finally, sex sorting (X) was combined with Hep-GSH and/or re frozen treatments. The use of Hep-GSH diminished cleavage rates from ICSI X re frozen group (80.4% vs. 94.2%) and blastocyst development from ICSI X group (3.3% vs. 10%), compared with their controls (p < 0.05). While Hep-GSH pretreatment induced lower transgene expression at day 4, no differences were found at the blastocyst stage between ICSI groups (from 58.3 to 80%). TUNEL assay showed higher DNA fragmentation indexes for all ICSI treatments (p < 0.05), except for ICSI X Hep-GSH, which did not differ from IVF X control. In conclusion, the use of normal size sperm pretreated with Hep-GSH, combined or not with sex-sorting by flow cytometry could improve ICSI outcomes in cattle. [ABSTRACT FROM AUTHOR]

The use of closed-loop salinity gradient power (SGP) technologies has been recently presented as a viable option to generate power using low-grade heat, by coupling a SGP unit with a thermally-driven regeneration process in a closed loop where artificial solutions can be adopted for the conversion of heat into power. Among these, the closed-loop reverse electrodialysis (RED) process presents a number of advantages such as the direct production of electricity, the extreme flexibility in operating conditions and the recently demonstrated large potentials for industrial scale-up. Ammonium hydrogen carbonate (NH4HCO3) is a salt suitable for such closed-loop RED process thanks to its particular properties. At temperatures above 40–45°C, it decomposes into a gaseous phase containing NH3, CO2and water. Thus, the use of NH4HCO3solutions for feeding a RED unit would allow their easy regeneration (after the power generation step) just using low-temperature waste heat in a purposely designed regeneration unit. This work aims at presenting an experimental investigation performed on a RED system fed with NH4HCO3solutions. Laboratory tests were carried out to find the best conditions for maximizing the power density and process performances of a RED unit by investigating a number of operating parameters such as fluid velocity and feed solutions concentration. [ABSTRACT FROM PUBLISHER]

Seawater brines, generated either by natural or anthropic processes, often cause significant environmental issues related to their disposal. A clear example is the case of brines from desalination plants, which can have severe environmental impacts on the receiving water body. On the other side, brines can represent a rich and appealing source of raw materials, especially when they are very concentrated, as it happens with bitterns (i.e. exhausted brines) produced in saltworks. In particular, magnesium concentration can reach values up to 30–40 kg/m3of brine, which is 20–30 times that of typical seawater. An experimental campaign has been carried out in the present work for assessing the potentials for magnesium recovery from concentrated brines. Real brines were collected from the final basins of the saltworks operating in the district of Trapani (Sicily, Italy). Experiments were performed both in a semi-batch and in a continuous 5 liters crystalliser operated by a reactive precipitation process. NaOH solutions were adopted as standard alkaline reactant in order to assess the influence of all operating parameters and reactor configuration on the recovery efficiency and purity of the Mg(OH)2powder produced. Results have highlighted a very promising strategy for the recovery of Mg from concentrated brines, which could be scaled up and applied to a number of different scenarios, including existing saltworks and newly designed integrated cycles for Zero Liquid Discharge desalination. [ABSTRACT FROM PUBLISHER]

The European eel Regulation EC 1100/2007 establishes measures to recover the European eel stock. The Regulation requires Member States to guarantee a spawner escapement ≥40% of pristine levels by reducing eel mortality. The complexity and plasticity of eel life history make it difficult to assess the effectiveness of alternative management options, and tools allowing decision makers and fishermen to quickly assess the effectiveness of proposed management scenarios are urgently needed. We used state-of-the-art knowledge to develop a user-friendly simulation software allowing users to evaluate if current management policies meet the conservation target and evaluate the expected performances (spawner escapement and fishing yield) of alternative management scenarios. The software relies upon a demographic model explicitly accounting for the most relevant features of eel demography and has default settings for specific geographical areas and water systems. We demonstrate the software by exploring a variety of management plans in three European water systems. [ABSTRACT FROM AUTHOR]

Abstract: Embryo disaggregation allows the production of two to four identical offspring from a single cow embryo. In addition, embryo complementation has become the technique of choice to demonstrate the totipotency of embryonic stem cells and induced pluripotent stem cells. Therefore, the aim of this study was to generate a new and simple method by aggregation in the well-of-the-well system to direct each single enhanced green fluorescent protein (egfp) eight-cell blastomere derived from bovine in vitro fertilization embryos to the inner cell mass (ICM) of chimeras produced with fused and asynchronic embryos. To this end, the best conditions to generate in vitro fertilization–fused embryos were determined. Then, the fused (F) and nonfused (NF) embryos were aggregated in two distinct conditions: synchronically (S), with both transgenic and F embryos produced on the same day, and asynchronically (AS), with transgenic embryos produced one day before F embryos. The highest fusion and blastocysts rates were obtained with two pulses of 40 V. The 2ASF and 2ASNF groups showed the best number of blastocysts expressing the EGFP protein (48% and 41%, respectively). Furthermore, the 2ASF group induced the highest localization rates of the egfp-expressing blastomere in the ICM (6/13, 46% of ICM transgene-expressing blastocysts). This technique will have great application for multiplication of embryos of high genetic value or transgenic embryos and also with the generation of truly bovine embryonic stem cells and induced pluripotent stem cells. [Copyright &y& Elsevier]

Abstract: Manufactured environmental toxins (METs) are a global problem, causing or contributing to health maladies across socioeconomic classes. This article is intended to educate pediatric nurse practitioners (PNPs) about select METs and their effects on the health of children. Infants and children are especially vulnerable to the effects of METs because of their physiological and developmental characteristics. Moreover, PNPs are obligated to be informed about METs and share their knowledge with families via anticipatory guidance so that caregivers can make informed decisions. PNPs should advocate for proper regulation of METs and prevention of their harmful effects. [Copyright &y& Elsevier]

Abstract: The objective was to evaluate the effects of cell cycle inhibitors (6-dimethylaminopurine [DMAP], and dehydroleukodine [DhL]) on transgene expression efficiency and on mosaic expression patterns of IVF bovine zygotes cytoplasmically injected with oolema vesicles coincubated with transgene. The DNA damage induced by the transgene or cell cycle inhibitors was measured by detection of phosphorylated histone H2AX foci presence (marker of DNA double-stranded breaks). Cloning of egfp blastomeres was included to determine continuity of expression after additional rounds of cellular division. The pCX-EGFP [enhanced green fluorescent protein gene (EGFP) under the chimeric cytomegalovirus IE-chicken-β-actin enhancer promoter control] gene plasmid (50 ng/μL) was injected alone (linear or circular exogenous DNA, leDNA and ceDNA, respectively) or associated with ooplasmic vesicles (leDNA-v or ceDNA-v). The effects of 2 mm DMAP or 1 μm DhL for 6 h (from 15 to 21 h post IVF) was evaluated for groups injected with vesicles. The DMAP increased (P < 0.05) egfp homogenous expression relative to transgene alone (21%, 18%, and 11% for leDNA-v + DMAP, leDNA-v, and leDNA, respectively) and also increased (P < 0.05) the phosphorylated histone H2AX foci area. Expression of egfp was higher (P < 0.05) for linear than for circular pCX-EGFP, and egfp blastocyst rates were higher (P < 0.05) for groups injected with linear transgene coincubated with vesicles than for linear transgene alone (95%, 77%, 84%, and 52% for leDNA-v + DMAP, leDNA-v + DhL, leDNA-v, and leDNA, respectively). Moreover, DMAP tended to improve egfp blastocysts rates for both circular and linear transgenes. Based on fluorescent in situ hybridization (FISH) analysis, there was evidence of integration in egfp embryos. Finally, clones derived from leDNA-v + DMAP had the highest egfp expression rates (96%, 65%, and 65% for leDNA-v + DMAP, leDNA-v, and leDNA, respectively). Transgenesis by cytoplasmic injection of leDNA-v + DMAP is a promising alternative for transgenic animal production. [Copyright &y& Elsevier]

Abstract: In order to establish conditions for intracytoplasmic sperm injection-mediated gene transfer (ICSI-MGT) in cattle, various aspects of fertilization and embryonic development were assessed after five activation treatments. Spermatozoa were co-incubated with pCX-EGFP (pCX-enhanced green fluorescent protein gene) plasmid and injected into metaphase II oocytes, which were then treated with ionomycin (Io), before further activation with the following agents: 6-dimethylaminopurine (Io-DMAP), additional Io plus DMAP (2Io-DMAP), Io alone (2Io), ethanol (Io-EtOH), or strontium chloride (Io-SrCl2). Fertilization rates at 16 h after ICSI, presence of a condensed spermatozoon head on Day 4 (Day 0 = ICSI), blastocyst and EGFP expression rates on Day 7, and Oct-4 pattern of Day 8 blastocysts were evaluated. Fertilization rates did not differ significantly among treatments. All (100%) of EGFP-positive embryos resulted from ICSI fertilization, whereas at least 60% of EGFP-negative embryos (>4 cells) had a condensed sperm head. Blastocyst rates after 2Io-DMAP were not significantly different from Io-DMAP or Io-EtOH, but they were higher than 2Io or Io-SrCl2 treatments (25.9, 18.7, 14.7, 9.4, and 10.9% respectively; P < 0.05). Transgene expression rates were higher for Io-DMAP, 2Io-DMAP and Io-SrCl2 than for 2Io and Io-EtOH (52.3, 53.0, 42.8, 28.2, and 29.4% respectively; P < 0.05). Over 80% of the blastocysts expressed egfp protein. In conclusion, ICSI-MGT was a powerful technique to produce bovine embryos that expressed the EGFP transgene. Moreover, the actual efficiency of ICSI-MGT could be readily evaluated by this method, which uses a marker expressed early in embryo development. [Copyright &y& Elsevier]