Insights into the oxidation resistance mechanism and tribological behaviors of multilayered TiSiN/CrVxN hard coatings

In the last decades,vanadium alloyed coatings have been introduced as potential candidates for self-lubrication due to their perfect tribological properties.In this work,the influence of V incorporation on the wear performance and oxidation resistance of TiSiN/CrN film coatings deposited by direct current(DC)reactive magnetron sputtering is investigated.The results show that vanadium incorporation significantly decreases the oxidation resistance of the coatings.In general,two layers are formed during the oxidation process:i)Ti(V)O_(2) on top,followed by a protective layer,which is subdivided into two layers,Cr_(2)O_(3) and Si-O.ii)The diffusion of V controls the oxidation of V-containing coatings.The addition of vanadium improves the wear resistance of coatings,and the wear rate decreases with increasing V content in the coatings;however,the friction coefficient is independent of the chemical composition of the coatings.The wear of the V-containing coatings is driven by polishing wear.

Tribological performance under different environments of Ti-C-N composite films for marine wear-resistant parts

The need for reducing the wear in mechanical parts used in the industry makes self-lubricant films one of the sustainable solutions to achieve long-term protection under different environmental conditions.The purpose of this work is to study the influence of C additions on the tribological behavior of a magnetron-sputtered TiN film in air,water,and seawater.The results show that the addition of C into the TiN binary film induced a new amorphous phase,and the films exhibited a dual phase of fcc(face-centered cubic)-TiN and amorphous carbon.The antifriction and wear-resistance properties were enhanced in air and water by adding 19.1at%C.However,a further increase in the C concentration improved anti-frictional properties but also led to higher wear rates.Although the amorphous phase induced microbatteries and accelerated the corrosion of TiN phases in seawater,the negative abrasion state was detected for all Ti-C-N films due to the adhesion of the tribocorrosion debris on the wear track.

Psychotropic drugs and liver disease:A critical review of pharmacokinetics and liver toxicity

The liver is the organ by which the majority of sub-stances are metabolized, including psychotropic drugs. There are several pharmacokinetic changes in end-stage liver disease that can interfere with the metabolization of psychotropic drugs. This fact is particularly true in drugs with extensive first--pass metabolism, highly protein bound drugs and drugs depending on phase I hepatic metabolic reactions. Psychopharmacological agents are also associated with a risk of hepatotoxicity. The evidence is insufficient for definite conclusions regarding the prevalence and severity of psychiatric drug-induced liver injury. High-risk psychotropics are not advised when there is pre-existing liver disease, and after starting a psychotropic agent in a patient with hepatic impairment, frequent liver function/lesion monitoring is advised. The authors carefully review the pharmacokinetic disturbances induced by end-stage liver disease and the potential of psychopharmacological agents for liver toxicity.

The impact of European firms＇ economic conditions and financial performance on accounting quality

In this study the authors analyse the possible effect of firms＇ economic conditions and financial performance on accounting quality. Bradshaw, et al. （2004）, Gelos ＆ WEI （2005） stated that financial reporting quality is fundamental for investors and it affects international capital movements. Following Schipper ＆ Vicent （2003）, the authors estimated accounting quality by abnormal accruals and earnings persistence. The authors＇ contribution consists of investigating a huge number of firms from 17 European countries using unbalanced panel data. The authors found evidence that economic conditions affect accounting quality： big firms and those with high current earnings exhibit better financial information. These results are robust because they do not depend on the accounting quality proxy, even when the authors estimated regression with economical and financial factors alone or together. Financial performance does not seem to affect accounting quality. However, this relation is not linear because in high leveraged firms, the capital structure becomes determinant.

Neuropsychological Aspects of Aging and Driving for Inclusive Automotive Interior Design

As people grow older, their cognitive functions undergo changes which may result in uncomfortable driving situations and even increase the risk of accidents. This research aims to understand the neuropsychological aspects of healthy aging and their possible relationship in changes in motor performance or ability. The research methodology is descriptive and includes a collection of basic studies in the scope of neuroscience, driving tasks, and older driver behavior. The final analysis points to certain changes in the functioning of the cerebral cortex and its connections as being responsible for poor performance in some basic driving tasks, but which can be compensated for by means of adapted mechanisms in motor vehicles. This study may contribute as a methodological tool, to the automobile design process, for the selection of Advanced Driver Assistance Systems (ADAS) or other emerging technologies which can compensate cognitive changes, improve safety, comfort and inclusion of older drivers in the future of automobile interior design. We conclude that in normal aging, people may present some cognitive deficits especially linked to the frontal and parietal lobe, which interfere with the necessary driving skills albeit not with the dangerous ones and can be compensated by technological solutions. The main innovation of this article is related to the bibliographical compilation and critical analysis in terms of identifying the neuropsychological aspects of normal human aging and car driving and its relationship with possible contributions from vehicular technology, as well its consider future trends in automotive interior design that should be analysed with caution in order to users inclusion.

Optical clearing mechanisms characterization in muscle

Optical immersion clearing is a technique that has been widely studied for more than two decades and that is used to originate a temporary transparency effect in biological tissues.If applied in cooperation with clinical methods it provides optimization of diagnosis and treatment procedures.This technique turns biological tissues more transparent through two main mechanisms-tissue dehydration and refractive index(RI)matching between tissue compo-nents.Such matching is obtained by partial replacement of interstit ial water by a biocompat ible agent that presents higher RI and it can be completely rever sible by natural rehydration in vrivo or by assisted rehydration in ex vivo tissues.Experimental data to characterize and discriminate between the two mechanisms and to find new ones are necessary.Using a simple method,based on collimated transmittance and thickness measurements made from muscle samples under treatment,we have estimated the diffusion properties of glucose,ethylene glycol(EG)and water that were used to perform such char acterization and discrimination.Comparing these properties with data from literature that characterize their diffusion in water we have observed that musde cell membrane permeability limits agent and water diffusion in the muscle.The same experi-mental data has allowed to calculate the optical dearing(OC)eficiency and make an inter-pretation of the internal changes that occurred in muscle during the treatments.The same methodology can now be used to perform similar studies with other agents and in other tissues in order to solve engineering problems at design of inexpensive and robust technologies for a consider.able improvement of optical tomogr aphic techmiques with better contrast and in depth imaging.

Experimental study on the wear evolution of different PVD coated tools under milling operations of LDX2101 duplex stainless steel

Duplex stainless steels are being used on applications that require,especially,high corrosion resistance and overall good mechanical properties,such as the naval and oil-gas exploration industry.The components employed in these industries are usually obtained by machining,however,these alloys have low machinability when compared to conventional stainless steels.In this work,a study of the wear developed when milling duplex stainless-steel,LDX 2101,is going to be presented and evaluated,employing four types of milling tools with different geometries and coatings,while studying the influence of feed rate and cutting length in the wear of these tools.Tools used have been provided with two and four flutes,as well as three different coatings,namely:TiAlN,TiAlSiN and AlCrN.The cutting behavior of these tools was analyzed;data relative to the cutting forces developed during the process were obtained;and roughness measurements of the machined surfaces were executed.The tools were then submitted to scanning electron microscope(SEM)analysis,enabling the identification of the wear mechanisms that tools were subjected to when machining this material,furthermore,the early stages of these mechanisms were also identified.All this work was done with the goal of relating the machining parameters and cutting force values obtained,identifying,and discussing the wear patterns that were observed in the coating and tools after the milling tests,providing further information on the machining of these alloys.

Governmental Support and Internal Control in Tourism Sector in Portugal

The COVID-19 pandemic affected the operational risk of organizations,requiring its management through Internal Control Systems(ICS).The tourism sector in Portugal,one of the largest and most competitive,was also one of the most affected by the pandemic,which emerged in March 2020.The main purpose of this paper is to analyse the perception of tourism managers about the relationship between the existence of internal control and risk mitigation in their companies.We present a quantitative study carried out by questionnaire,sent to 830 managers from tourism companies in the region of Porto,Portugal.Most participants consider crucial the implementation of ICS and a competitive advantage in the current pandemic context.They also consider that the implementation of ICS is not accessible to all companies,but its absence does not necessarily make them more fragile.The study also concludes that besides internal control,the role of the Portuguese Government was crucial to overcome the difficulties caused by the pandemic and to ensure companies’recovery.Financial support from the government allows companies to invest in procedures to overcome the pandemic situation,such as strengthening cleanliness measures,focusing on new technologies,and creating products and/or services more attractive to consumers.This study contributes to the perception of tourism managers about internal control,highlight the need to implement risk analysis routines to manage risks that may threaten the company activities,and highlight the government’s role in business recovery.

Accounting and the ＂Doctor-Manager Relationship＂

The adoption of the ＂new public management＂ in the hospital sector brought about greater presence and power to professional managers in hospitals, thus increasing the risk of conflict in the doctor-manager relationship. Aiming to enrich the discussion on the factors that could be the bases for this conflict and considering the role of accounting, the study presented here corresponds, basically, to what we call ＂content analysis＂ of qualitative studies. The results demonstrate that the Portuguese doctors as the sample studied accept, in essence, the principles of enterprise management and recognize the use of accounting information in the scope of their functions as long as they are called to participate as legitimate actors, and authorities respect their desires to preserve a practice which they consider of quality.

Reviving Direct Observation Methods for Physical Activity Behavior

Purpose:Current Direct Observation(DO)methods are burdensome to the observer and relevant limitations can be identified on the outcome information.This study aims to characterize DO from the observers’point of view and to analyze the feasibility and usefulness of visual information in the form of video.Method:data collection was done with ten adult males,observed while performing different physical activities in an indoor court.Sessions were video recorded by two cameras.Three observers performed systematic observation,using SOPLAY,with different sampling rates.Inter observer’s agreement and with reference data was analyzed by Cohen’s Kappa statistic.Results:SOPLAY highest agreement between observers was 0.611 on vigorous category and walking category had the lowest 0.188.It doubles the time needed to annotate the video with pauses,but half of player’s behavior is preserved.Conclusion(s):using video to support DO permits to collect more accurate data and a more detailed behavior categorization is warranted.Developments in computer vision are expected to reduce the human efforts in DO methods.

Patients’ perceptions, health and psychological changes with obesity treatment: Success and failure in a triangulation study

The present study aims to understand changes in health problems, health complaints and coping strategies, during the obesity treatment process with qualitative and quantitative data. Thirty bariatric patients were interviewed before bariatric surgery and at a 12-month follow-up, and fulfilled self-report measures about health problems, health complaints and coping strategies before surgery, at 6-and 12-month follow-ups. Before surgery, failure cases differ from success on the conceptualization of obesity, However, there are no other differences between groups. At 6-and 12-month follow-ups, failure cases had the highest BMI, health problems and complaints and less % EWL than success cases. One year after the surgery, one in each three persons did not lose the expected weight, i.e., are failure cases. Before surgery, there are no differences between success and failure cases in the report of health problems, health complaints and coping strategies, but they have different conceptualizations of their obesity and treatment. One year after the surgery, success cases understood bariatric surgery as an important moment in their lives related to their expected results, whereas failures valued unexpected dimensions and still waiting for a miracle surgery without their personal commitment. Accordingly, it is necessary to consider lifestyle changes in the obesity treatment process.

Phenazines:Natural products for microbial growth control

The unprecedented problem of antibiotic resistance has become a major challenge for public health,which has contributed to an increase in infections caused by such bacteria.These microbial infections,typically biofilm-related,are alsocoupled to an increase in human mortality and morbidity.However,the demand for new antimicrobial agents hasincreased along with the evolution of microbial resistance mechanisms.Natural products produced by bacteria,such as phenazines,have been recognized as an important source for the development of new antimicrobial agents,through the exploitation of their capacity to increase oxidative stress in other organisms.Phenazines are a large groupof nitrogen-containing heterocyclic compounds and are essential for several cellular processes including iron acquisition,signaling events,enzymatic processes,and biofilm formation.Phenazine-inspired antibiotics(i.e.,2-bromo-1-hydroxyphenazine,2,4-dibromo-1-hydroxyphenazine,bromophenazine-21,phenazine-13,and phenazine-14)are veryactive against a wide range of gram-positive and gram-negative bacteria,including those associated with severe infections.In this study,mechanisms of phenazine-inspired antibiotics in the cellular processes of planktonic and sessilebacteria are reviewed.Moreover,the application of phenazine-inspired antibiotics for the eradication of multidrugresistant planktonic and biofilm bacterial infections is also reviewed.

Stability analysis of uncertain fractional-order neutral-type delay systems with actuator saturation

This study analyzes the problem of robust stability of fractional-order delay systems of neutral type under actuator saturation.A Lyapunov–Krasovskii(LK)function is constructed and conditions of the asymptotic robust stability of such systems are given,which are formulated by linear matrix inequalities(LMIs),using the Lyapunov direct method.An algorithm is introduced to compute the gain of the state feedback controller for extending the domain of attraction.The theoretical results are validated using some numerical examples.

Analysis of antisym metric cross-ply laminates using high-order shear deformation theories:a meshless approach

For many years finite element method(FEM)was the chosen numerical method for the analysis of composite structures.However,in the last 20 years,the scientific community has witnessed the birth and development of several meshless methods,which are more flexible and equally accurate numerical methods.The meshless method used in this work is the natural neighbour radial point interpolation method(NNRPIM).In order to discretize the problem domain,the NNRPIM only requires an unstructured nodal distribution.Then,using the Voronoi mathematical concept,it enforces the nodal connectivity and constructs the background integration mesh.The NNRPIM shape functions are constructed using the radial point interpolation technique.In this work,the displacement field of composite laminated plates is defined by high-order shear deformation theories.In the end,several antisymmetric cross-ply laminates were analysed and the NNRPIM solutions were compared with the literature.The obtained results show the efficiency and accuracy of the NNRPIM formulation.

A novel color image encryption algorithm based on a fractional-order discrete chaotic neural network and DNA sequence operations

A novel color image encryption algorithm based on dynamic deoxyribonucleic acid(DNA)encoding and chaos is presented.A three-neuron fractional-order discrete Hopfield neural network(FODHNN)is employed as a pseudo-random chaotic sequence generator.Its initial value is obtained with the secret key generated by a fiveparameter external key and a hash code of the plain image.The external key includes both the FODHNN discrete step size and order.The hash is computed with the SHA-2 function.This ensures a large secret key space and improves the algorithm sensitivity to the plain image.Furthermore,a new three-dimensional projection confusion method is proposed to scramble the pixels among red,green,and blue color components.DNA encoding and diffusion are used to diffuse the image information.Pseudo-random sequences generated by FODHNN are employed to determine the encoding rules for each pixel and to ensure the diversity of the encoding methods.Finally,confusion II and XOR are used to ensure the security of the encryption.Experimental results and the security analysis show that the proposed algorithm has better performance than those reported in the literature and can resist typical attacks.

Intelligent negotiation model for ubiquitous group decision scenarios

Supporting group decision-making in ubiquitous contexts is a complex task that must deal with a large amount of factors to succeed. Here we propose an approach for an intelligent negotiation model to support the group decision-making process specifically designed for ubiquitous contexts. Our approach can be used by researchers that intend to include arguments, complex algorithms, and agents' modeling in a negotiation model. It uses a social networking logic due to the type of communication employed by the agents and it intends to support the ubiquitous group decision-making process in a similar way to the real process, which simultaneously preserves the amount and quality of intelligence generated in face-to-face meetings. We propose a new look into this problem by considering and defining strategies to deal with important points such as the type of attributes in the multicriterion problems, agents' reasoning, and intelligent dialogues.

Distributed Energy Resource Scheduling with Focus on Demand Response Complex Contracts

Demand response(DR)is a flexible way to improve distributed energy resource scheduling.The innovative contribution of this paper is to include complex contracts in the model,which can accommodate the constraints according to the special expectations of each player.Such contracts are included in the optimization of distributed energy resource scheduling to dispatch DR according to the expectations of consumers.Multi-period DR events are considered.In this way,consumers can specify the limits on the time,power,and remuneration regarding participation in DR events,which has not been considered in the literature.The state of the art treats these aspects separately or uses a statistical approach,without providing consumers with options to combine their preferences regarding different aspects of their flexibility deployment.The model has been validated for 218 consumers using several scenarios and different types of distributed generation,showing that it is possible to increase DR with respect to the preferences of consumers.