Performance Analysis of XOR-Based Routing Protocols in Vehicular ad hoc Networks

This book is part of a series exploring the dynamic universe of the Internet in the 21st century. Collected here are papers discussing a wide range of topics and issues impacting and relating to the Internet such as: internet traffic conditioning methods applied to wireless networks; design knowledge management and sharing using XML; FGPA-Based video streaming; internet traffic modeling and an analysis of XOR-based flat routing protocols. (Imprint: Nova Press

6β-Chloro-5α-hydr­oxy-20-oxopregnan-3β-yl acetate

The title steroid, C23H35ClO4, is a pregnane derivative prepared by ring opening of the corresponding 5α,6α-ep­oxy steroid with BiCl3. There are two symmetry-independent mol­ecules in the asymmetric unit that show no significant differences concerning bond lengths and angles. The conformation of the six-membered rings in both mol­ecules is close to a chair form, while the five-membered ring adopts an envelope conformation. All rings in both mol­ecules are trans-fused. The mol­ecules are held together by an extensive O—H⋯O hydrogen-bonding network

Innovative reactor prototype for Hydrogen production in a stationary application using sodium borohydride

Hydrogen storage has proved to be the greatest obstacle preventing hydrogen from replacing fossil fuels. Hence, a safe, efficient and economical method of storing hydrogen must be available to turn viable a hydrogen economy based on renewable resources [1]. Hydrogen can be stored in chemical hydrides such as sodium borohydride (NaBH4), with large theoretical H2 content of 10,9 wt%. With the aid of catalysts, and at room temperatures, the alkaline hydrolysis of NaBH4 can be enhanced [2]. In this work, a 100 L innovative reactor for hydrogen production was designed, based on the optimized layout of a laboratorial scale reactor [3], as part of a project financed by the Portuguese financial support program NSRF. The developed system has the capability to feed a 5 kW PEM fuel cell with a maximum hydrogen consumption of 75 slpm. The NaBH4 solution is stored in a 50 L reservoir from where seven consecutive 7,0 L injections to the reactor are possible. The Ni-Ru based catalyst applied can be re-used several times without losing its performance [1] and because of this capacity its replacement will be done, manually, every seven NaBH4 solution injections (simultaneously with the residual solution removal and the reactor cleaning). The catalyst should then be recovered for further utilization. Additionally to the reactor, a 400 to 500 L reservoir was also designed to be used as the system buffer since the reactor works in batch mode and it is desired that the PEMFC operates continuously. The system was conceived for stationary applications and eventually to be installed in remote areas, reason why the systemś monitoring and control are fully automatized. Its hydropneumatic circuit layout is characterized by four parts: injection system, reactor, valves bloc and buffer. It is assumed that the designed system can operate continuously throughout 15 hours with a medium hydrogen consumption of 10 slpm, which can supply a daily household energy power demand

A comprehensive comparison of voltage and current control techniques for three-phase VSI converters

Converting electrical energy from direct current to alternate current, or vice versa, is one of the most frequently performed tasks in today’s electrical systems. The Voltage Source Inverter (VSI) is the most widely used topology to accomplish this task. This paper compares the performance of three control algorithms for voltage source inverter (VSI) with PI, PR and MP control algorithms were applied for voltage control and current control. For voltage control the VSI synthesizes the sinusoidal voltage system for an islanded application. In current control the VSI injects energy into the power grid by synthesizing sinusoidal currents. A general comparison is made of the performance of the three control algorithms under the presented conditions, helping to choose the control algorithm to use in a given application.This work has been supported by FCT – Fundação para a Ciência e Tecnologia within the Project Scope: UIDB/00319/2020. This work has been supported by the FCT Project QUALITY4POWER PTDC/EEI-EEE/28813/2017, and by the FCT Project DAIPESEV PTDC/EEI-EEE/30382/2017. Mr. Luis A. M. Barros is supported by the doctoral scholarship PD/BD/143006/2018 granted by the Portuguese FCT foundation

How can biomolecules improve mucoadhesion of oral insulin? A comprehensive insight using ex-vivo, in silico, and in vivo models

Funding: Supported in part by UID/DTP/04138/2019 from FCT, Portugal and DREAMS (ULHT). SEM analysis was funded by FCT/MCTES for the financial support to CESAM (UIDP/50017/2020+UIDB/50017/2020), through national funds.Currently, insulin can only be administered through the subcutaneous route. Due to the flaws associated with this route, it is of interest to orally deliver this drug. However, insulin delivered orally has several barriers to overcome as it is degraded by the stomach’s low pH, enzymatic content, and poor absorption in the gastrointestinal tract. Polymers with marine source like chitosan are commonly used in nanotechnology and drug delivery due to their biocompatibility and special features. This work focuses on the preparation and characterization of mucoadhesive insulin-loaded polymeric nanoparticles. Results showed a suitable mean size for oral administration (<600 nm by dynamic laser scattering), spherical shape, encapsulation efficiency (59.8%), and high recovery yield (80.6%). Circular dichroism spectroscopy demonstrated that protein retained its secondary structure after encapsulation. Moreover, the mucoadhesive potential of the nanoparticles was assessed in silico and the results, corroborated with ex-vivo experiments, showed that using chitosan strongly increases mucoadhesion. Besides, in vitro and in vivo safety assessment of the final formulation were performed, showing no toxicity. Lastly, the insulin-loaded nanoparticles were effective in reducing diabetic rats’ glycemia. Overall, the coating of insulin-loaded nanoparticles with chitosan represents a potentially safe and promising approach to protect insulin and enhance peroral delivery.publishersversionpublishe

Influence of feeding graded levels of canned sardines on the inflammatory markers and tissue fatty acid composition of Wistar rats

The present study was supported by Fundacao para a Ciencia e a Tecnologia (FCT) through the grant PTDC-SAU/OSM/2006/70560 (principal investigator: P. O. R). S. V. M. is the recipient of a FCT individual fellowship SFRH/BPD/2009/63019 and P. A. L. is a researcher involved in the FCT programme 'Ciencia 2008'.Canned sardines are a ready-to-use fish product with excellent nutritional properties owing to its high n-3 long-chain PUFA content, mainly EPA (20 : 5n-3) and DHA (22 : 6n-3). The present study aimed to assess the effect of two dosages of canned sardines, recommended for the primary and secondary prevention of human CVD, on the inflammatory marker concentrations and fatty acid composition of erythrocytes and key metabolic tissues (liver, muscle, adipose tissue and brain) in the rat model. Wistar rats were fed a diet containing 11\% (w/w) of canned sardines (low-sardine (LS) diet) and a diet containing 22\% (w/w) of canned sardines (high-sardine (HS) diet) for 10 weeks. Daily food intake, weight gain, and organ and final body weights were not affected by the dietary treatments. The concentrations of total cholesterol, HDL-cholesterol and LDL-cholesterol decreased in both the LS and HS groups, while those of alanine aminotransferase and adiponectin increased. The concentrations of IL-1 beta increased only with the highest dosage of sardine. The dose-dependent influence of the graded levels of EPA+DHA was tissue specific. Compared with that of other tissues and erythrocytes, the fatty acid composition of the brain was less affected by the canned sardine-supplemented diets. In contrast, the retroperitoneal adipose tissue was highly responsive. The deposition ratios of EPA and DHA indicated that the LS diet was optimal for DHA deposition across the tissues, except in the retroperitoneal adipose tissue. Taken together, our findings indicate that a LS diet positively affects plasma lipid profiles and inflammatory mediators, whereas a HS diet has contradictory effects on IL-1 beta, which, in turn, is not associated with variations in the concentrations of other pro-inflammatory cytokines. This finding requires further investigation and pathophysiological understanding.publishersversionpublishe

A novel molecular link between HOXA9 and WNT6 in glioblastoma identifies a subgroup of patients with particular poor prognosis

Despite much effort to improve treatments, patients with malignant glioma still present a very poor prognosis that has not changed significantly in the last decades. In this context, it is crucial to better understand glioma pathogenesis to identify new molecular prognostic subgroups and therapeutic targets. WNT6 was recently identified as a new oncogenic molecule in glioblastoma (GBM), with prognostic value in patients, but the mechanisms underlying WNT6 aberrant expression in glioma are still unknown. WNT6 was overexpressed in a subset of gliomas independently of IDH mutations, 1p/19q codeletion status, and WNT6 gene copy number. Interestingly, WNT6 expression is associated with the DNA methylation levels of particular CpG regions at both the WNT6 promoter and the gene body in glioma patient samples. HOXA9, a transcription factor previously associated with poorer clinical outcome in GBM, was identified as a novel transcriptional regulator of WNT6, activating the WNT/β-catenin pathway in vitro and in vivo. In various cohorts of glioma patients, mRNA levels of WNT6 and HOXA9 were significantly correlated, extending our in vitro and in vivo findings into the clinical setting. Interestingly, this novel molecular link between WNT6 and HOXA9 was not limited to glioma, as they were co-expressed also in patients with other tumor types. Clinically, WNT6 was a prognostic biomarker of shorter survival in GBM, independently of HOXA9 expression. Concomitant high expression of both WNT6 and HOXA9 identified a subgroup of patients with particularly dismal survival. These findings describe novel WNT6 regulatory mechanisms in GBM, establishing particular DNA methylation patterns and HOXA9 as critical regulators of WNT6 expression in glioma. This HOXA9-WNT6 molecular link supports WNT signaling in GBM cells and is a powerful prognostic biomarker, highlighting the clinical relevance of this axis in patients. Novel therapies targeting WNT6-HOXA9 signaling may thus be useful for this deadly disease.info:eu-repo/semantics/publishedVersio