222 research outputs found

    From Urban Façade to Green Foundation: Re-Imagining the Garden City to Manage Climate Risks

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    Climate risk management evolves rapidly from one additional challenge for urban planning into a radical driver of urban development. In addition to fundamental changes in urban planning to increase long-term resilience, the creation of new opportunities for sustainable transformation is imperative. While urban planners increasingly add climate risks to their menu, implementation of effective action is lagging. To reduce urban infrastructure's vulnerability to heat and flooding, cities often rely on short-term incremental adjustments rather than considering longer-term transformative solutions. The transdisciplinary co-development of inspiring urban visions with local stakeholders over timescales of decades or more, can provide an appealing prospect of the city we desire - a city that is attractive to live and work in, and simultaneously resilient to climate hazards. Taking an historic perspective, we argue that re-imagining historical urban planning concepts, such as the late 19th-century garden city until early 21st century urban greening through nature-based solutions, is a pertinent example of how climate risk management can be combined with a wide-range of socio-economic and environmental goals. Climate knowledge has expanded rapidly over the last decades. However, climate experts mainly focus on the refinement of and access to observations and model results, rather than on translating their knowledge effectively to meet today’s urban planning needs. In this commentary we discuss how the two associated areas (urban planning and climate expertise) should be more fully integrated to address today’s long-term challenges effectively

    Thermo-mechanical analysis of flexible and stretchable systems

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    This paper presents a summary of the modeling and technology developed for flexible and stretchable electronics. The integration of ultra thin dies at package level, with thickness in the range of 20 to 30 μ m, into flexible and/or stretchable materials are demonstrated as well as the design and reliability test of stretchable metal interconnections at board level are analyzed by both experiments and finite element modeling. These technologies can achieve mechanically bendable and stretchable subsystems. The base substrate used for the fabrication of flexible circuits is a uniform polyimide layer, while silicones materials are preferred for the stretchable circuits. The method developed for chip embedding and interconnections is named Ultra Thin Chip Package (UTCP). Extensions of this technology can be achieved by stacking and embedding thin dies in polyimide, providing large benefits in electrical performance and still allowing some mechanical flexibility. These flexible circuits can be converted into stretchable circuits by replacing the relatively rigid polyimide by a soft and elastic silicone material. We have shown through finite element modeling and experimental validation that an appropriate thermo mechanical design is necessary to achieve mechanically reliable circuits and thermally optimized packages

    Ecosystem-based climate change adaptation for Essenvelt, Middelburg, The Netherlands

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    Climate change is an internationally recognised phenomenon generally held accountable for the increasing magnitude of extremes in both climatic events and temperature. With increasing urbanization and the concentration of socio-economic activities in urban areas, the challenge to contend with climate change is particularly pertinent in cities. In response to climate-change impacts, a range of climate-adaptation strategies have been developed to make cities increasingly ‘climate proof’. A qualitative research approach is employed to review climate change, its impacts and some adaptation strategies, focusing on ecosystem-based adaptation strategies from Belgium and The Netherlands and Water-Sensitive Urban Design approaches developed in Australia. The article engages a case study of Essenvelt, Middelburg, The Netherlands, where unanticipated warmer night-time temperatures are a primary concern, related to natural variability, the urban heat island effect and climate change. The article proposes certain adaptation measures for Essenvelt, based on the adaptation strategies reviewed

    The effect of land-atmosphere feedbacks on the spatial structure of land surface fluxes over heterogeneous terrain

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    The ability to understand and accurately map land surface fluxes at the spatial resolutions of human activity can support efforts to define the impact of anthropogenic induced land cover changes on hydrological and ecological processes. While remote sensors can map the surface states, the scientific problem arises from an incomplete knowledge of how heterogeneous surface states excite heterogeneity in the states of the lower atmosphere, which feedback on the exchange rates of mass, energy, and momentum across these heterogeneous land surfaces. Through the development and implementation of a framework for merging remotely sensed land surface data into a Large Eddy Simulation (LES) model of the atmospheric boundary layer, a procedure now exists for evaluating the typical ecohydrological modeling assumption of homogeneous atmospheric variables (i.e. decoupled from surface heterogeneity) over a study region. The strength of the feedback effects (or surface-air state coupling), with particular attention to the effect of variability of surface states on atmospheric properties in the surface layer, has been shown in our previous work to depend on both the length scales of the surface features [Albertson et al., 2001] and the magnitude of the contrast in surface states across the features [Kustas and Albertson, 2003]. Ignoring consideration of the feedback effects can lead to erroneous flux estimation since most landscapes are inherently heterogeneous. In this talk we examine new results and present a simple scale-dependent means to account for surface-atmosphere coupling in the estimation of land surface fluxes from remotely sensed data over complex terrain

    A double blind randomized controlled trial comparing primary suture closure with mesh augmented closure to reduce incisional hernia incidence

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    Background: Incisional hernia is the most frequently seen long term complication after laparotomy causing much morbidity and even mortality. The overall incidence remains 11-20%, despite studies attempting to optimize closing techniques. Two patient groups, patients with abdominal aortic aneurysm and obese patients, have a risk for incisional hernia after laparotomy of more than 30%. These patients might benefit from mesh augmented midline closure as a means to reduce incisional hernia incidence. Methods/design. The PRImary Mesh Closure of Abdominal Midline Wound (PRIMA) trial is a double-blinded international multicenter randomized controlled trial comparing running slowly absorbable suture closure with the same closure augmented with a sublay or onlay mesh. Primary endpoint will be incisional hernia incidence 2 years postoperatively. Secondary outcomes will be postoperative complications, pain, quality of life and cost effectiveness.A total of 460 patients will be included in three arms of the study and randomized between running suture closure, onlay mesh closure or sublay mesh closure. Follow-up will be at 1, 3, 12 and 24 months with ultrasound imaging performed at 6 and 24 months to objectify the presence of incisional hernia. Patients, investigators and radiologists will be blinded throughout the whole follow up. Disccusion. The use of prosthetic mesh has proven effective and safe in incisional hernia surgery however its use in a prophylactic manner has yet to be properly investigated. The PRIMA trial will provide level 1b evidence whether mesh augmented midline abdominal closure reduces incisional hernia incidence in high risk groups. Trial registration. Clinical trial.gov NCT00761475

    High accuracy theoretical investigations of CaF, SrF, and BaF and implications for laser-cooling

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    The NL-eEDM collaboration is building an experimental setup to search for the permanent electric dipole moment of the electron in a slow beam of cold barium fluoride molecules [Eur. Phys. J. D, 72, 197 (2018)]. Knowledge of molecular properties of BaF is thus needed to plan the measurements and in particular to determine an optimal laser-cooling scheme. Accurate and reliable theoretical predictions of these properties require incorporation of both high-order correlation and relativistic effects in the calculations. In this work theoretical investigations of the ground and the lowest excited states of BaF and its lighter homologues, CaF and SrF, are carried out in the framework of the relativistic Fock-space coupled cluster (FSCC) and multireference configuration interaction (MRCI) methods. Using the calculated molecular properties, we determine the Franck-Condon factors (FCFs) for the A2Π1/2→X2Σ1/2+A^2\Pi_{1/2} \rightarrow X^2\Sigma^{+}_{1/2} transition, which was successfully used for cooling CaF and SrF and is now considered for BaF. For all three species, the FCFs are found to be highly diagonal. Calculations are also performed for the B2Σ1/2+→X2Σ1/2+B^2\Sigma^{+}_{1/2} \rightarrow X^2\Sigma^{+}_{1/2} transition recently exploited for laser-cooling of CaF; it is shown that this transition is not suitable for laser-cooling of BaF, due to the non-diagonal nature of the FCFs in this system. Special attention is given to the properties of the A′2ΔA'^2\Delta state, which in the case of BaF causes a leak channel, in contrast to CaF and SrF species where this state is energetically above the excited states used in laser-cooling. We also present the dipole moments of the ground and the excited states of the three molecules and the transition dipole moments (TDMs) between the different states.Comment: Minor changes; The following article has been submitted to the Journal of Chemical Physics. After it is published, it will be found at https://publishing.aip.org/resources/librarians/products/journals

    The Protein Synthesis Inhibitor Anisomycin Induces Macrophage Apoptosis in Rabbit Atherosclerotic Plaques through p38 Mitogen-Activated Protein Kinase

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    ABSTRACT Because macrophages play a major role in atherosclerotic plaque destabilization, selective removal of macrophages represents a promising approach to stabilize plaques. We showed recently that the protein synthesis inhibitor cycloheximide, in contrast to puromycin, selectively depleted macrophages in rabbit atherosclerotic plaques without affecting smooth muscle cells (SMCs). The mechanism of action of these two translation inhibitors is dissimilar and could account for the differential effects on SMC viability. It is not known whether selective depletion of macrophages is confined to cycloheximide or whether it can also be achieved with translation inhibitors that have a similar mechanism of action. Therefore, in the present study, we investigated the effect of anisomycin, a translation inhibitor with a mechanism of action similar to cycloheximide, on macrophage and SMC viability. In vitro, anisomycin induced apoptosis of macrophages in a concentration-dependent manner, whereas SMCs were only affected at higher concentrations. In vivo, anisomycin selectively decreased the macrophage content of rabbit atherosclerotic plaques through apoptosis. The p38 mitogen-activated protein kinase (MAPK) inhibitor SB202190 [4-(4-fluorophenyl)-2-(4-hydroxyphenyl)-5-(4-pyridyl)-1H-imidazole] prevented anisomycin-induced macrophage death, without affecting SMC viability. SB202190 decreased anisomycin-induced p38 MAPK phosphorylation, did not alter c-Jun NH 2 -terminal kinase (JNK) phosphorylation, and increased extracellular signal-regulated kinase (ERK) 1/2 phosphorylation. The latter effect was abolished by the mitogenactivated protein kinase kinase 1/2 inhibitor U0126 [1,4-diamino-2,3-dicyano-1,4-bis(2-aminophynyltio)butadiene ethanolate], although the prevention of anisomycin-induced macrophage death by SB202190 remained unchanged. The JNK phosphorylation inhibitor SP600125 did not affect anisomycin-induced macrophage or SMC death. In conclusion, anisomycin selectively decreased the macrophage content in rabbit atherosclerotic plaques, indicating that this effect is not confined to cycloheximide. p38 MAPK, but not ERK1/2 or JNK, plays a major role in anisomycin-induced macrophage death

    Systematic study and uncertainty evaluation of P, T-odd molecular enhancement factors in BaF

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    A measurement of the magnitude of the electric dipole moment of the electron (eEDM) larger than that predicted by the Standard Model (SM) of particle physics is expected to have a huge impact on the search for physics beyond the SM. Polar diatomic molecules containing heavy elements experience enhanced sensitivity to parity (P) and time-reversal (T)-violating phenomena, such as the eEDM and the scalar-pseudoscalar (S-PS) interaction between the nucleons and the electrons, and are thus promising candidates for measurements. The NL-eEDM collaboration is preparing an experiment to measure the eEDM and S-PS interaction in a slow beam of cold BaF molecules [P. Aggarwal et al., Eur. Phys. J. D 72, 197 (2018)]. Accurate knowledge of the electronic structure parameters, Wd and Ws, connecting the eEDM and the S-PS interaction to the measurable energy shifts is crucial for the interpretation of these measurements. In this work, we use the finite field relativistic coupled cluster approach to calculate the Wd and Ws parameters in the ground state of the BaF molecule. Special attention was paid to providing a reliable theoretical uncertainty estimate based on investigations of the basis set, electron correlation, relativistic effects, and geometry. Our recommended values of the two parameters, including conservative uncertainty estimates, are 3.13 ±0.12×1024Hzecm for Wd and 8.29 ± 0.12 kHz for W

    Enchytraeus albidus Microarray: Enrichment, Design, Annotation and Database (EnchyBASE)

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    Enchytraeus albidus (Oligochaeta) is an ecologically relevant species used as standard test organisms for risk assessment. Effects of stressors in this species are commonly determined at the population level using reproduction and survival as endpoints. The assessment of transcriptomic responses can be very useful e.g. to understand underlying mechanisms of toxicity with gene expression fingerprinting. In the present paper the following is being addressed: 1) development of suppressive subtractive hybridization (SSH) libraries enriched for differentially expressed genes after metal and pesticide exposures; 2) sequencing and characterization of all generated cDNA inserts; 3) development of a publicly available genomic database on E. albidus. A total of 2100 Expressed Sequence Tags (ESTs) were isolated, sequenced and assembled into 1124 clusters (947 singletons and 177 contigs). From these sequences, 41% matched known proteins in GenBank (BLASTX, e-value≤10-5) and 37% had at least one Gene Ontology (GO) term assigned. In total, 5.5% of the sequences were assigned to a metabolic pathway, based on KEGG. With this new sequencing information, an Agilent custom oligonucleotide microarray was designed, representing a potential tool for transcriptomic studies. EnchyBASE (http://bioinformatics.ua.pt/enchybase/) was developed as a web freely available database containing genomic information on E. albidus and will be further extended in the near future for other enchytraeid species. The database so far includes all ESTs generated for E. albidus from three cDNA libraries. This information can be downloaded and applied in functional genomics and transcription studies
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