118 research outputs found

    Interactive industrial application to represent isothermal sections of multi component phase diagram

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    “Make the slag and the steel will make itself” is an old phrase in steelmaking. The converter or basic oxygen furnace (BOF) process is a necessary step in the steel production during which carbon, phosphorus and other impurities present in the hot metal, coming from the blast furnace, are removed and steel is produced. This steel is tapped from the converter and further refined, next cast, rolled and finished. The BOF process is complex due to many reasons: high temperatures, multiple phases present, interactions of kinetics and thermodynamics, etc. Emphasis in this work is put upon the BOF steelmaking slag. Yet, even though this has been topic of many research projects no full understanding of all the slag related phenomena has been far from achieved. One of the difficulties is the multi-component nature of the slag. In its most simplified form, the slag is a three component system consisting of CaO, SiO2 and FeOn. However, in practical applications this slag contains more than three components, making graphical representations of equilibria complex and difficult. This work shows the potential to apply CALPHAD based data for industrial applications via an interactive visual tool. Isothermal sections of multi-components phase diagrams were constructed with Factsage 7.1 software. Addition of extra components to the calculated isothermal sections, gives a graphical representation which can be used to gain insight in certain observed phenomena in the BOF process. To illustrate that the interactive visualisation yields an interesting tool to integrate CALPHAD based calculations in industry two case studies from steelmaking are discussed: the effect of MgO upon the refractory wear and the effect of MgO upon dephosphorization

    Rainfall monitoring with opportunistic sensors

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    High-resolution rainfall observations are desirable, especially in urban areas. However, most traditional rain sensors measure rain indirectly at a considerable elevation (weather radar), or only in rural areas (WMO standard rain gauges). Opportunistic sensors are devices that are not intended for large-scale rainfall monitoring, but can be used as such. One example is commercial microwave links: microwave signals are transmitted between antennas for the purpose of telecommunication, and the signal power drop due to rainfall can be used to estimate link path-averaged rain rate. Another technique is crowdsourcing of rainfall measurements by amateur weather stations from online weather platforms. These two techniques provide rainfall information based on the already existing infrastructure. Quality control and rainfall retrieval methods are applied to obtain valuable rainfall information. With validation studies the relative potential for operational rainfall monitoring is demonstrated.</p

    Validatie en optimalisatie bosvriendelijke houtexploitatie in Vlaanderen: eindrapport

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    Vapor nanobubble is the more reliable photothermal mechanism for inducing endosomal escape of siRNA without disturbing cell homeostasis

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    Strategies for controlled delivery of therapeutic siRNA into living cells are in high demand as endosomal escape remains the most prominent bottleneck at the intracellular level. Photothermal properties of gold nanoparticles (AuNP) can be used to overcome the endosomal membrane barrier upon laser irradiation by two mechanisms: endosomal rupture by mechanical energy from water vapor nanobubbles (VNBs), or permeabilization of the endosomal membrane by heat diffusion. Here we evaluated how both mechanisms influence cargo release, transfection efficiency, acute cytotoxicity and cell homeostasis. Using a siRNA/AuNP drug delivery system we found that the in vitro release of siRNA from the AuNP carrier occurs equally efficiently by VNB formation or heat generation. Heat-mediated endosomal escape happened more efficiently in cells that had more particles per endosome, resulting in variable siRNA-induced downregulation (20-50%). VNB-mediated endosomal escape did not dependent on the number of AuNP per endosome, yielding high downregulations (50-60%) independent of the cell type. Effects on cell homeostasis by whole transcriptome analysis, showed a quick recover after 24 h or 48 h for either of both photothermal mechanisms. We conclude that VNBs are more consistent to induce efficient endosomal escape and gene silencing independent of the cell type without long lasting effects on cell homeostasis

    Distress in parents of children with first-onset steroid-sensitive nephrotic syndrome

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    Background:Steroid-sensitive nephrotic syndrome (SSNS) is associated with a relapsing–remitting course that can be stressful for parents. As little is known of parental distress at the first onset of SSNS, this study aims to describe parental distress and everyday problems in mothers and fathers of a child with newly diagnosed SSNS participating in a randomized controlled trial of levamisole added to corticosteroids. 'Methods: To assess distress, the Distress Thermometer for Parents (DT-P) was used, which includes questions on distress (thermometer score 0–10, ≥ 4 “clinical distress”) and presence of everyday problems in six domains: practical, social, emotional, physical, cognitive, and parenting. The DT-P was completed 4 weeks after the onset of SSNS. Total sum and individual items of everyday problems were compared with reference data from mothers and fathers of the Dutch general population. Results: There was no difference in clinically elevated parental distress between SSNS mothers (n = 37) and fathers (n = 25) and reference parents. Compared to reference fathers, fathers of a child with SSNS scored significantly higher on emotional problems (P = 0.030), while mothers experienced more parenting problems (P = 0.002). Regression analyses showed that lower parental age and having a girl with SSNS were significantly associated with more practical problems and higher distress thermometer scores, respectively. Conclusions: Four weeks after onset, SSNS mothers and fathers experience equal distress as reference parents. However, both parents endorsed significantly more everyday problems. Therefore, monitoring parental distress, even in the first weeks of the disease, could contribute to timely interventions and prevent worsening of problems. Clinical trial registry: Dutch Trial Register (https://onderzoekmetmensen.nl/en/trial/27331 ). Graphical abstract: [Figure not available: see fulltext.]</p

    Health-related quality of life of children with first onset steroid-sensitive nephrotic syndrome

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    This study assessed HRQoL and emotional and behavioral difficulties (EBD) and associated variables in children with first onset SSNS. While relapsing steroid-sensitive nephrotic syndrome (SSNS) in children is associated with lower health-related quality of life (HRQoL), little is known about first onset. Four weeks after onset, children (2–16 years) and/or their parents who participated in a randomized placebo-controlled trial, completed the Pediatric Quality of Life Inventory 4.0 (PedsQL) and Strengths and Difficulties Questionnaire (SDQ) to measure HRQoL and EBD, respectively. Total and subscale scores and the proportion of children with impaired HRQoL (&gt; 1 SD below the mean of the reference group) or SDQ clinical scores (&lt; 10th and &gt; 90th percentile) were compared to the Dutch general population (reference group). Regression analyses were used to identify associated variables. Compared to the reference group, children 8–18 years reported significantly lower total HRQoL, and physical and emotional functioning. A large proportion (&gt; 45%) of these children had impaired HRQoL. There were no differences in HRQoL between children 2–7 years and the reference group, except for higher scores on social functioning (5–7 years). Similar proportions of SSNS and reference children scored within the clinical range of SDQ subscales. Age, sex, and steroid side-effects were negatively associated with HRQol and/or EBD. Conclusion: This study showed that HRQoL and EBD are affected in children of different ages with first onset SSNS. This calls for more awareness from healthcare providers and routinely monitoring of HRQoL and EBD in daily clinical care to prevent worsening of symptoms. Clinical trial registry: Netherlands Trial Register (https://trialsearch.who.int/ ; NTR7013), date of registration: 02 June 2018. What is Known: • Health-related quality of life (HRQoL) is lower and emotional and behavioral difficulties (EBD) is more affected in children with frequently-relapsing and steroid-dependent nephrotic syndrome. What is New: • HRQoL and EBD are affected in children with first onset steroid-sensitive nephrotic syndrome compared to a reference group of the Dutch general population. • To what extent HRQoL and EBD are affected depends on the age of the patient.</p

    Quantifying synergies and trade-offs in the global water-land-food-climate nexus using a multi-model scenario approach

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    The human-earth system is confronted with the challenge of providing a range of resources for a growing and more prosperous world population while simultaneously reducing environmental degradation. The sustainable development goals and the planetary boundaries define targets to manage this challenge. Many of these are linked to the land system, such as biodiversity, water, food, nutrients and climate, and are strongly interconnected. A key question is how measures can be designed in the context of multi-dimensional sustainability targets to exploit synergies. To address this, a nexus approach is adopted that acknowledges the interconnectedness between the important sub-systems water, land, food, and climate. This study quantifies synergies and trade-offs from ambitious interventions in different components of this water-land-fod-climate nexus at the global scale. For this purpose, a set of six harmonized scenarios is simulated with the model of agricultural production and its impact on the environment and Integrated model to assess the global environment models. The multi-model approach improves robustness of the results while shedding light on variations coming from different modelling approaches. Our results show that measures in the food component towards healthy diets with low meat consumption have synergies with all other nexus dimensions: Increased natural land improving terrestrial biodiversity (+4% to +8%), lower greenhouse gas emissions from land (−45% to −58%), reduced irrigation water withdrawals to protect or restore hydrological environmental flows (−3% to −24%), and reductions in nitrogen surpluses (−23% to −35%). Climate mitigation measures in line with the Paris Agreement have trade-offs with the water and food components of the nexus, as they adversely affect irrigation water withdrawals (+5% to +30% in 2050 compared to reference scenario) and food prices (+1% to +20%). The analysis of a scenario combining all measures reveals how certain measures are in conflict while others reinforce each other. This study provides an example of a nexus approach to scenario analysis providing input to the next generation of pathways aiming to achieve multiple dimensions of sustainable development.SHAPEHorizon 2020 Framework Programmehttp://dx.doi.org/10.13039/100010661Deutsche Bundesstiftung Umwelthttp://dx.doi.org/10.13039/100007636Peer Reviewe

    A feasibility study of a complete low-cost consumer-grade brain-computer interface system

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    Brain-computer interfaces (BCIs) are technologies that provide the user with an alternative way of communication. A BCI measures brain activity (e.g. EEG) and converts it into output commands. Motor imagery (MI), the mental simulation of movements, can be used as a BCI paradigm, where the movement intention of the user can be translated into a real movement, helping patients in motor recovery rehabilitation. One of the main limitations for the broad use of such devices is the high cost associated with the high-quality equipment used for capturing the biomedical signals. Different low-cost consumer-grade alternatives have emerged with the objective of bringing these systems closer to the final users. The quality of the signals obtained with such equipments has already been evaluated and found to be competitive with those obtained with well-known clinical-grade devices. However, how these consumer-grade technologies can be integrated and used for practical MI-BCIs has not yet been explored. In this work, we provide a detailed description of the advantages and disadvantages of using OpenBCI boards, low-cost sensors and open-source software for constructing an entirely consumer-grade MI-BCI system. An analysis of the quality of the signals acquired and the MI detection ability is performed. Even though communication between the computer and the OpenBCI board is not always stable and the signal quality is sometimes affected by ambient noise, we find that by means of a filter-bank based method, similar classification performances can be achieved with an MI-BCI built under low-cost consumer-grade devices as compared to when clinical-grade systems are used. By means of this work we share with the BCI community our experience on working with emerging low-cost technologies, providing evidence that an entirely low-cost MI-BCI can be built. We believe that if communication stability and artifact rejection are improved, these technologies will become a valuable alternative to clinical-grade devices.Fil: Peterson, Victoria. Universidad Nacional de Entre Ríos; ArgentinaFil: Galván, Catalina María. Universidad Nacional del Litoral; ArgentinaFil: Hernández, Hugo. Universidad Nacional de Entre Ríos; ArgentinaFil: Spies, Ruben Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Matemática Aplicada del Litoral. Universidad Nacional del Litoral. Instituto de Matemática Aplicada del Litoral; Argentin
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