Wear behavior of Ti6Al4V biomedical alloys processed by selective laser melting, hot pressing and conventional casting

The aim of this work was to study the influence of the processing route on the microstructural constituents,hardness andtribological(wear and friction)behavior of Ti6Al4V biomedical alloy.In this sense,three different processing routes were studied:conventional casting,hot pressing and selective laser melting.A comprehensive metallurgical,mechanical and tribologicalcharacterization was performed by X-ray diffraction analysis,Vickers hardness tests and reciprocating ball-on-plate wear tests ofTi6Al4V/Al2O3sliding pairs.The results showed a great influence of the processing route on the microstructural constituents andconsequent differences on hardness and wear performance.The highest hardness and wear resistance were obtained for Ti6Al4Valloy produced by selective laser melting,due to a markedly different cooling rate that leads to significantly different microstructurewhen compared to hot pressing and casting.This study assesses and confirms that selective laser melting is potential to producecustomized Ti6Al4V implants with improved wear performance.

Mediterranean Berries as Inhibitors of Lipid Oxidation in Porcine Burger Patties Subjected to Cooking and Chilled Storage

The efifciency of extracts from Arbutus unedo L. （AU）, Crataegus monogyna L. （CM）, Rosa canina L. （RC）, and Rubus ulmifolius Schott. （RU） to inhibit lipid oxidation in raw, cooked and cooked and chilled （2°C/12 d） porcine burger patties, was investigated. The modiifcation of the fatty acid proifle during processing treatments （cooking and chilling）, the quantitative measurements of thiobarbituric acid reactive substances （TBA-RS）, and lipid-derived volatiles, were used as indicators of lipid oxidation. Polyunsaturated fatty acids （PUFA） gradually decreased during cooking and the subsequent storage of cooked burger patties with this decrease being signiifcantly greater （P〈0.05） in control patties than in those with added berry extracts. In accordance, the control patties showed signiifcantly higher TBA-RS numbers and counts of lipid-derived volatiles in all treatments when compared to the berry-added counterparts （P〈0.05）. Results from the present work show, for the ifrst time, that extracts from A. unedo, C. monogyna, R. canina, and R. ulmifolius are promising antioxidants which could enhance the nutritional, safety and sensory properties of porcine burger patties.

Corrosion behaviour of PEEK or β-TCP-impregnated Ti6Al4V SLM structures targeting biomedical applications

Ti6Al4V cellular structures were produced by selective laser melting(SLM)and then filled either with beta-tricalcium phosphate(β-TCP)or PEEK(poly-ether-ether-ketone)through powder metallurgy techniques,to improve osteoconductivity and wear resistance.The corrosion behavior of these structures was explored considering its importance for the long-term performance of implants.Results revealed that the incorporation of open cellular pores induced higher electrochemical kinetics when being compared with dense structures.The impregnation ofβ-TCP and PEEK led to the creation of voids or gaps between the metallic matrix and the impregnated material which also influenced the corrosion behavior of the cellular structures.

Constrained Fractional Variational Problems of Variable Order

Isoperimetric problems consist in minimizing or maximizing a cost functional subject to an integral constraint.In this work, we present two fractional isoperimetric problems where the Lagrangian depends on a combined Caputo derivative of variable fractional order and we present a new variational problem subject to a holonomic constraint. We establish necessary optimality conditions in order to determine the minimizers of the fractional problems. The terminal point in the cost integral,as well as the terminal state, are considered to be free, and we obtain corresponding natural boundary conditions.

Modelling of Eruptive Fire Occurrence and Behaviour

Eruptive fires are one of the main causes of human losses in forest fire fighting. The sudden change in fire behaviour due to a fire eruption is extremely dangerous for fire-fighters because it is unpredictable. Very little literature is available to support either modelling or occurrence prediction for this phenomenon. In this study, an unsteady physical model of fire spread is detailed, which describes the initiation and development of eruptive fires with an induced wind sub-model. The latter phenomenon is proposed as the mainspring of fire eruptions. Induced wind is proportional to the rate of spread and the rate of spread is in a non-linear relationship with induced wind. This feedback can converge or diverge depending on the conditions. The model allows both explaining why an eruption can occur and predicting explicitly its occurrence according to meteorological conditions, topographic parameters, fuel bed properties and fire front width. The model is tested by comparing its results to a set of experiments carried out at laboratory scale and during an outdoor wildfire, the Kornati accident.

Antioxidant and antitumor potential of wild and IMT-Acultivated Osmundea pinnatifida

Osmundea pinnatifida is a red edible seaweed known as pepper dulse.O.pinnatifida was cultivated in the farm of ALGAplus(ílhavo,Portugal).This farm is integrated with a seabream and seabass commercial aquaculture and uses the nutrient-enriched water resultant from the fish production as its cultivation medium in the integrated multi-trophic aquaculture(IMTA)manner.Wild and IMTA-cultivated samples of O.pinnatifi da were screened for antioxidant and antitumor activities.The antioxidant capacity of solvent extracts from wild and IMTA cultivated samples was assessed in two methods(2,2-diphenyl-1-picrylhydrazyl(DPPH)and oxygen radical absorbance capacity(ORAC)),and their total phenolic contents(TPC)were estimated.Antitumor activity was evaluated in three different tumor cell lines(HepG-2,MCF-7,and SH-SY5Y)through 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT)assay.Among the solvents used for extraction,dichloromethane was the most eff ective to extract phenolic compounds and presented higher ORAC.A significant correlation was found between TPC and ORAC,which was also sustained by the principal components analysis(PCA).Dichloromethane extracts induced a cytostatic eff ect on MCF-7 cells and showed weak cytotoxicity to SH-SY5Y cells and weak impact on cell proliferation.Overall,there were no statistically signifi cant differences in the biological activities shown by the wild and IMTA-cultivated samples.Hence,O.pinnatifida can be obtained in an economical and environmentally sustainable way through IMTA,maintaining bioactive properties in a high potential for further nutraceutical purposes.

Seismic safety assessment of existing masonry infill structures in Nepal

Reinforced concrete（RC） buildings in Nepal are constructed with RC frames and masonry infill panels. These structures exhibit a highly non-linear inelastic behavior resulting from the interaction between the panels and frames. This paper presents an extensive case study of existing RC buildings in Nepal. Non-linear analyses were performed on structural models of the buildings considered as a bare frame and with masonry infill, in order to evaluate the influence of infill walls on the failure mechanisms. Five three-storey buildings with different structural configurations and detailing were selected. The effect of masonry infill panels on structural response was delineated by comparing the bare-framed response with the infill response. Seismic performance is evaluated with regard to global strength, stiffness, energy dissipation, inter-storey drift, and total deflection of the structure. A parametric analysis of structures with masonry infill is also performed. For this, the influence of different material properties is studied, namely diagonal compressive stress, modulus of elasticity and tensile stress of masonry infill panels. Study results show that masonry infill increases the global strength and stiffness of the structures; it decreases the inter-storey drift and hence the total displacement of the structure. The results quantify the influence of the infill panels on structural response and, in particular, the effect of the diagonal compressive strength of the masonry wall.

SACI Protocol: Preliminary Guidelines for the Development of Digital Health Technologies for Clinical Trials in Brazil

In the last decade, evidence-based medical practice has been supported on a large scale by computerized decision support tools, aiming to reduce diagnostic and therapeutic uncertainty, complementing the actions of the health professional. With technological developments, it is now possible to consider these systems as part of clinical intervention, both for the diagnosis and treatment of diseases. The literature has described the implementation of e-health tools, that is, technological innovations in the health area such as software, applications, serious games, among others, as a strategy to improve the process and adherence to treatment. However, there is still no standardized instrument in Brazil that can be used to guide the development, from the research phase, and the implementation of these tools as a health intervention, also impacting patient outcomes. With the objective of investigating a new therapeutic and preventive form, based on intervention with a computerized system, this work proposes the creation of guidelines for the registration and implementation of e-health tools as a clinical intervention. The proposal aims to be able to assist in the reporting standardization from the development stage to the application of the e-health tool helping in the treatment of diseases, registering all the experience lived in the research and applying it in different contexts of health.

Evaluation of the Usability of a Telehealth System for COVID-19 According to the Perception of the User Professional

With the advent of the pandemic, the Brazilian Ministry of Health structured in record time the Telehealth Service of the Unified Health System called TeleSUS, an ecosystem based on the intensive use of information technology involving automated mechanisms and a personalized health care center at distance. In addition to constant evaluations carried out in the service as a public health strategy, at clinical and epidemiological levels, the team involved in the project was also concerned with evaluating the system developed to enable the operation of remote care, from the conception of the organization of health actions to the technological development of the digital health tool. The objective of this study was to carry out an evaluation of a telehealth system, measuring the degree of satisfaction of users of health professionals regarding its usability and identifying factors that positively and/or negatively influence the evaluation.

The Biotechnological and Seafood Potential of Stichopus regalis

Sea cucumbers are highly used not only for the production of the bêche-de-mer, but also recent studies have been showing the high potential of these marine invertebrates on the pharmaceutical industry, as they are rich in bioactive compounds with important functions. Stichopus regalis extracts (1 mg·mL-1) were used in antioxidant, antimicrobial and antitumor assays. The lipid profile was also evaluated. No significant antioxidant activity was detected in both methanolic and dichloromethane extracts. The methanolic fraction showed the highest antimicrobial potential against Candida albicans with an IC50 of 475.4 μg·mL-1. In the antitumor assays, the dichloromethane fraction showed a high potential for both cell lines, as revealed by the MTT method. The total fat content was 3.63% ± 0.11% and the fatty acid profile revealed the highest amount in C16:0 (9.43% ± 0.77%), C18:0 (12.43% ± 0.83%), C18:1 ω7 (5.63% ± 0.33%), EPA (12.49% ± 0.15%), DHA (7.35% ± 0.02%), ARA (19.29% ± 0.14%) and a ω3/ω6 ratio of 1.078. These findings led us to suggest the potential use of S. regalis as a new source of bioactive compounds with pharmacological potential and its nutritional benefits for human health.

Control of Indoor Swimming Pools with Potential for Demand Response

Buildings with indoor swimming pools are recognized as very high-energy consumers and present a great potential for electrical and thermal energy savings. A BEMS （building energy management system） could be conceived in order to optimize the building energy demand and with smart grid interaction. This paper presents the condition and potential contract-based demand side response in indoor swimming pools context. The BEMS designed by the authors implements control strategies for HVAC （heating, ventilation and air conditioning） and pumping system in order to reduce the electricity demand during peak hours or in response to an emergency signal from the system operator in critical times. The control strategies for HVAC was carried out by Building Thermal Simulation and the used of a theoretical formula for pumping system, strategies can carry out a significant reduction in power demand both in HVAC and pumping systems.

3D Photo-Fabrication for Tissue Engineering and Drug Delivery

The most promising strategies in tissue engineering involve the integration of a triad of biomaterials, living cells, and biologically active molecules to engineer synthetic environments that closely mimic the healing milieu present in human tissues, and that stimulate tissue repair and regeneration. To be clinically effective, these environments must replicate, as closely as possible, the main characteristics of the native extracellular matrix(ECM) on a cellular and subcellular scale. Photo-fabrication techniques have already been used to generate 3D environments with precise architectures and heterogeneous composition, through a multi-layer procedure involving the selective photocrosslinking reaction of a light-sensitive prepolymer. Cells and therapeutic molecules can be included in the initial hydrogel precursor solution, and processed into 3D constructs. Recently, photofabrication has also been explored to dynamically modulate hydrogel features in real time, providing enhanced control of cell fate and delivery of bioactive compounds. This paper focuses on the use of 3D photo-fabrication techniques to produce advanced constructs for tissue regeneration and drug delivery applications. State-of-the-art photo-fabrication techniques are described, with emphasis on the operating principles and biofabrication strategies to create spatially controlled patterns of cells and bioactive factors. Considering its fast processing, spatiotemporal control, high resolution, and accuracy, photo-fabrication is assuming a critical role in the design of sophisticated 3D constructs. This technology is capable of providing appropriate environments for tissue regeneration, and regulating the spatiotemporal delivery of therapeutics.

Understanding Tremor in Rapid Upper Limb Movements Using 3D Accelerometers Data

Tremor is a manifestation of a variety of human neurodegenerative diseases, notably Parkinson’s disease (PD) and Essential Tremor (ET), both affecting millions worldwide. PD is primarily caused by a progressive loss of dopamine neurons in the nigrostriatal system that leads to widespread motor symptoms such as bradykinesia, rigidity, tremor and postural instability. ET typically involves a tremor of the arms, hands or fingers. No definitive test or biomarker is yet available for PD or ET, so the rate of misdiagnosis is relatively high. As tremor is a very common feature at the onset of both diseases, it is crucial to be able to characterize it. This is made possible using acce?lerometers to quantify the tremor amplitude and frequency. In this work we aim to find tasks involving upper limb movements that are suitable to modulate both types of tremor. Four tasks were tested, differing on whether the arms moved together or alternatingly and whether loads were added. Significant differences in tremor measures were found when patients were asked to perform simultaneous rapid arms movements with loads placed on their wrists. These results may allow the design of an efficient fMRI protocol for identifying the cortical circuits responsible for the modulation of tremor.

Management Accounting Practices in the Portuguese Lodging Industry

This paper aims to characterize management accounting techniques at the Portuguese lodging industry, identifying the techniques adopted and the determinants of adopting them and their adequacy for the decision-making process. It is also a purpose to understand the extent to which the industry adopts the Uniform System of Accounts for the Lodging Industry （USALI）. The sample includes 35 hotels, which were analyzed in the years 2009 and 2010. Evidence is found supporting the fact management accounting is a tool incorporated in the daily management practices of hotels and useful to support the decision-making process. The proportion used of traditional management accounting techniques is higher than the proportion of use of contemporary ones. The adoption of these techniques is influenced by the fact of the hotels being subsidiaries of a multinational hotel chain, as well as by their annual turnover. In Portugal, there is a weak use of USALI. It is more used in the large hotels and in hotels with a foreign control. Management accounting supports hotels to improve their performance, thus becoming relevant to analyze management accounting practices used by them, particularly which instruments and techniques. In this context, this study, the first of its kind in Portugal, is justified with the increasing need for accurate and actual information of the accounting practices of the hotels operating in Portugal.

Surface Fires： No Wind, No Slope, Marginal Burning

The first aim of this work is to provide an analytical expression to calculate the rate of spread of surface fires under no wind and no slope conditions. A previous simplified model was improved for this particular case of fire propagation. The test of this proposed model was performed by using two complete sets of experimental results with several fuel beds and variable parameters such as moisture content or bulk density. The second aim of this article is to highlight two conditions that allow stopping a fire： the low leaf area and the high value of the moisture content.

Open Source Tool for Networks Management Communication

Considering the complexity of the networks and the need for telecommunication operators （Telco） to present innovations to their clients, the quickest possible, one of the solutions for this complexity could be to centralize its configuration. Thus the SDN （software-defmed networking） concept may be an important solution. This paper suggests the implementation of a tool to support the development and testing of networks and services before they are put into production. The use of a tool that simplifies the configuration of a network service makes the networks and services to be less susceptible to errors and failures by those who set them up, thus allowing telecom operators, among others, to be able to create new services, improve the monitorization of their human resources and, above all, improve their fmancial results. In the end, success will be achieved because with a simple interaction and basic knowledge we are able to manage network services.

High Value Materials from the Forests

The design, process and synthesis of high value composite materials from forests in scientific research has been widely discussed in recent times ensuring greater awareness and accessibility to its associated communities and the economy in general. Raw materials obtained from the forests can be multi-folded in its use as a virgin source of an energy provider such as wooden blocks to more complex processed material development. In this paper, we will be focusing on the latter related to sustainable development of rosins. Rosins are exudates of pine resins which consist of hydrophobic characteristics that are widely used as a precursor for many applications without significant alterations. We discuss the nature, process and its support in composite material. The composite material has been tailored with related to chemical and physical properties. Chemically rosins contain free carboxyl acid functional group and carbon-carbon double bonds which are potent to react with other reactive species to facilitate various intermediates. Here we have looked at its reaction intermediates and subsequent products for composite material of high value using environmentally friendly methodologies, such as solvent free methods. Biodegradable polymer incorporated composite scaffolds using rosins are studied to tailor the bioactivity. We treat the eco-friendly pine resins which is biocompatible to complement the biopolymers as the process of extracting rosin from pine resin is a particular green process, involving only a natural product (pine resin) and producing no waste. The paper discusses the preparation of composite scaffolds for use in tissue engineering applications.

Metal alginates for polyphenol delivery systems: Studies on crosslinking ions and easy-to-use patches for release of protective flavonoids in skin

Incorporation of bioactive natural compounds like polyphenols is an attractive approach for enhanced functionalities of biomaterials.In particular flavonoids have important pharmacological activities,and controlled release systems may be instrumental to realize the full potential of these phytochemicals.Alginate presents interesting attributes for dermal and other biomaterial applications,and studies were carried here to support the development of polyphenol-loaded alginate systems.Studies of capillary viscosity indicated that ionic medium is an effective strategy to modulate the polyelectrolyte effect and viscosity properties of alginates.On gelation,considerable differences were observed between alginate gels produced with Ca^2+,Ba^2+,Cu^2+,Fe^2+,Fe^3+and Zn^2+as crosslinkers,especially concerning shrinkage and morphological regularity.Stability assays with different polyphenols in the presence of alginate-gelling cations pointed to the choice of calcium,barium and zinc as safer crosslinkers.Alginate-based films loaded with epicatechin were prepared and the kinetics of release of the flavonoid investigated.The results with calcium,barium and zinc alginate matrices indicated that the release dynamics is dependent on film thicknesses,but also on the crosslinking metal used.On these grounds,an alginate-based system of convenient use was devised,so that flavonoids can be easily loaded at simple point-of-care conditions before dermal application.This epicatechin-loaded patch was tested on an ex-vivo skin model and demonstrated capacity to deliver therapeutically relevant concentrations on skin surface.Moreover,the flavonoid released was not modified and retained full antioxidant bioactivity.The alginate-based system proposed offers a multifunctional approach for flavonoid controllable delivery and protection of skin injured or under risk.

Seismic fragility assessment of revised MRT buildings considering typical construction changes

The present study investigates the vulnerability assessment of the prototype revised Mandatory Rule of Thumb(MRT)buildings initially designed and detailed for three storeys bare frame building;later modified through variable number of storeys(three,four,and five)and different arrangement of infill walls(bare frame,soft-storey,irregular infilled,and fully infilled).The application of infill walls increases the fundamental frequencies,stiffness,and maximum strength capacity,but reduces the deformation capability than the bare frame building.The vulnerability was also reduced through infill walls,where the probability of exceeding partial-collapse and collapse damage reduced by 80% and 50%,respectively.Furthermore,the increased in storeys(three to five)also increases the failure probability,such that partial-collapse and collapse for fully infilled increases by almost 55% and 80%,respectively.All obtained results and discussions concluded that the structural sections and details assigned for MRT building is not sufficient if considered as bare frame and soft-storey.And increase in number of storeys causes building highly vulnerable although the infill walls were considered.

Mechanical properties characterization of different types of masonry infill walls

It is remarkable,the recent advances concerning the development of numerical modeling frameworks to simulate the infill panels'seismic behavior.However,there is a lack of experimental data of their mechanical properties,which are of full importance to calibrate the numerical models.The primary objective of this paper is to present an extensive experimental campaign of mechanical characterization tests of infill masonry walls made with three different types of masonry units:lightweight vertical hollow concrete blocks and hollow clay bricks.Four different types of experimental tests were carried out,namely:compression strength tests,diagonal tensile strength tests,and flexural strength tests parallel and perpendicular to the horizontal bed joints.A total amount of 80 tests were carried out and are reported in the present paper.The second objective of this study was to compare the mechanical properties of as-built and existing infill walls.The results presented and discussed herein,will be in terms of strain-stress curves and damages observed within the tests.It was observed a fragile behavior in the panels made with hollow clay horizontal bricks,without propagation of cracks.The plaster increased the flexural strength by 57%.