74 research outputs found
RSM approach for stochastic sensitivity analysis of the economicsustainability of a methanol production plant using renewable energy sources
This study aims at investigating the economic viability, at the pre-feasibility level, of a 5 MW electrolyserbase-methanol production plant, coupled with a PV power plant. The Authors investigated the impact ofdifferent parameters, such as the PV plant size, the electrical energy cost and the components capitalcosts on the methanol production cost and on the system economic viability. It was also analyzed theminimum recommended sale price of the methanol in order to assure an adequate time frame for thereturn of the investment, considering a different combination of the investigated parameters.An economic sensitivity analysis, based on the RSM approach, was performed in order to define themost promising economic conditions under which the plant can be considered a profitable investment interms of ARR. A guide for an economically viable plant design, allowing for the identification of the mostsuitable combination of the economic parameters, was proposed as a kind of\u201cmaps of existence\u201d. For thereference case, the Methanol Production Cost (MPC) resulted around 324V/ton and the minimummethanol sale price to achieve a PBP of 10 years. The sensitivity analysis identified the cost of electricityand the capital cost of the electrolyser as the most affecting parameters for the system economic viability.In terms of ARR, the methanol price represents the most significant factor. Considering a methanol saleprice ranging between 400 and 1200eur/ton, the ARR varied from 5% (20 year of PBP) to 20% (5years ofPBP). From the environmental point of view, it is worth underling that the methanol production planthere proposed allows to recycle about 5800 tons of CO2per year and to avoid the consumption of about5.2 MNm3of NG per year (compared to the traditional production)
Turbocharged Solid Oxide Fuel Cell System: Design and Emulation
This paper presents a design model of a turbocharged solid oxide fuel cell system fueled by biogas. The aim of this plant layout is the development of a low-cost solution considering the coupling of the solid oxide fuel cell (SOFC) with a low-cost machine such as a turbocharger (instead of a microturbine). The whole system model calculates the operational conditions and realizes the coupling between the turbocharger, the recuperator and the solid oxide fuel cell system (comprising SOFC, air preheater, fuel compressor and pre-heater, reformer, off-gas burner and anodic ejector). This model also supports the design of an emulator test rig in which a burner, located inside a thermal insulated vessel, replaces the solid oxide fuel cell system. The emulator test rig will be useful to study the matching between the turbocharger and the fuel cell to validate simulation models, design innovative solutions and test the control system of the whole plant
Antisense RNA Controls LRP1 Sense Transcript Expression through Interaction with a Chromatin-Associated Protein, HMGB2
SummaryLong non-coding RNAs (lncRNAs), including natural antisense transcripts (NATs), are expressed more extensively than previously anticipated and have widespread roles in regulating gene expression. Nevertheless, the molecular mechanisms of action of the majority of NATs remain largely unknown. Here, we identify a NAT of low-density lipoprotein receptor-related protein 1 (Lrp1), referred to as Lrp1-AS, that negatively regulates Lrp1 expression. We show that Lrp1-AS directly binds to high-mobility group box 2 (Hmgb2) and inhibits the activity of Hmgb2 to enhance Srebp1a-dependent transcription of Lrp1. Short oligonucleotides targeting Lrp1-AS inhibit the interaction of antisense transcript and Hmgb2 protein and increase Lrp1 expression by enhancing Hmgb2 activity. Quantitative RT-PCR analysis of brain tissue samples from Alzheimer’s disease patients and aged-matched controls revealed upregulation of LRP1-AS and downregulation of LRP1. Our data suggest a regulatory mechanism whereby a NAT interacts with a ubiquitous chromatin-associated protein to modulate its activity in a locus-specific fashion
Lightweight and Effective Convolutional Neural Networks for Vehicle Viewpoint Estimation From Monocular Images
Vehicle viewpoint estimation from monocular images is a crucial component for autonomous driving vehicles and for fleet management applications. In this paper, we make several contributions to advance the state-of-the-art on this problem. We show the effectiveness of applying a smoothing filter to the output neurons of a Convolutional Neural Network (CNN) when estimating vehicle viewpoint. We point out the overlooked fact that, under the same viewpoint, the appearance of a vehicle is strongly influenced by its position in the image plane, which renders viewpoint estimation from appearance an ill-posed problem. We show how, by inserting in the model a CoordConv layer to provide the coordinates of the vehicle, we are able to solve such ambiguity and greatly increase performance. Finally, we introduce a new data augmentation technique that improves viewpoint estimation on vehicles that are closer to the camera or partially occluded. All these improvements let a lightweight CNN reach optimal results while keeping inference time low. An extensive evaluation on a viewpoint estimation benchmark and on actual vehicle camera data shows that our method significantly outperforms the state-of-the-art in vehicle viewpoint estimation, both in terms of accuracy and memory footprint
SMO Inhibition Modulates Cellular Plasticity and Invasiveness in Colorectal Cancer
Colon Cancer (CC) is the fourth most frequently diagnosed tumor and the second leading cause of death in the USA. Abnormalities of Hedgehog pathway have been demonstrated in several types of human cancers, however the role of Hedgehog (Hh) in CC remain controversial. In this study, we analyzed the association between increased mRNA expression of GLI1 and GLI2, two Hh target genes, and CC survival and recurrence by gene expression microarray from a cohort of 382 CC patients. We found that patients with increased expression of GLI1 showed a statistically significant reduction in survival. In order to demonstrate a causal role of Hh pathway activation in the pathogenesis of CC, we treated HCT 116, SW480 and SW620 CC cells lines with GDC-0449, a pharmacological inhibitor of Smoothened (SMO). Treatment with GDC-0449 markedly reduced expression of Hh target genes GLI1, PTCH1, HIP1, MUC5AC, thus indicating that this pathway is constitutively active in CC cell lines. Moreover, GDC-0449 partially reduced cell proliferation, which was associated with upregulation of p21 and downregulation of CycD1. Finally, treatment with the same drug reduced migration and three-dimensional invasion, which were associated with downregulation of Snail1, the EMT master gene, and with induction of the epithelial markers Cytokeratin-18 and E-cadherin. These results were confirmed by SMO genetic silencing. Notably, treatment with 5E1, a Sonic Hedgehog-specific mAb, markedly reduced the expression of Hedgehog target genes, as well as inhibited cell proliferation and mediated reversion toward an epithelial phenotype. This suggests the existence of a Hedgehog autocrine signaling loop affecting cell plasticity and fostering cell proliferation andmigration/invasion in CC cell lines. These discoveries encourage future investigations to better characterize the role of Hedgehog in cellular plasticity and invasion during the different steps of CC pathogenesis.Peer reviewe
A promoter-proximal transcript targeted by genetic polymorphism controls E-cadherin silencing in human cancers.
Long noncoding RNAs are emerging players in the epigenetic machinery with key roles in development and diseases. Here we uncover a complex network comprising a promoter-associated noncoding RNA (paRNA), microRNA and epigenetic regulators that controls transcription of the tumour suppressor E-cadherin in epithelial cancers. E-cadherin silencing relies on the formation of a complex between the paRNA and microRNA-guided Argonaute 1 that, together, recruit SUV39H1 and induce repressive chromatin modifications in the gene promoter. A single nucleotide polymorphism (rs16260) linked to increased cancer risk alters the secondary structure of the paRNA, with the risk allele facilitating the assembly of the microRNA-guided Argonaute 1 complex and gene silencing. Collectively, these data demonstrate the role of a paRNA in E-cadherin regulation and the impact of a noncoding genetic variant on its function. Deregulation of paRNA-based epigenetic networks may contribute to cancer and other diseases making them promising targets for drug discovery
Impact of liver cirrhosis, severity of cirrhosis and portal hypertension on the difficulty of laparoscopic and robotic minor liver resections for primary liver malignancies in the anterolateral segments
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