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This paper aims to provide a metaheuristic approach to drone array optimization applied to coverage area maximization of wireless communication systems, with unmanned aerial vehicle (UAV) base stations, in the context of suburban, lightly to densely wooded environments present in cities of the Amazon region. For this purpose, a low-power wireless area network (LPWAN) was analyzed and applied. LPWAN are systems designed to work with low data rates but keep, or even enhance, the extensive area coverage provided by high-powered networks. The type of LPWAN chosen is LoRa, which operates at an unlicensed spectrum of 915 MHz and requires users to connect to gateways in order to relay information to a central server; in this case, each drone in the array has a LoRa module installed to serve as a non-fixated gateway. In order to classify and optimize the best positioning for the UAVs in the array, three concomitant bioinspired computing (BIC) methods were chosen: cuckoo search (CS), flower pollination algorithm (FPA), and genetic algorithm (GA). Positioning optimization results are then simulated and presented via MATLAB for a high-range IoT-LoRa network. An empirically adjusted propagation model with measurements carried out on a university campus was developed to obtain a propagation model in forested environments for LoRa spreading factors (SF) of 8, 9, 10, and 11. Finally, a comparison was drawn between drone positioning simulation results for a theoretical propagation model for UAVs and the model found by the measurements. [ABSTRACT FROM AUTHOR]

Coordinated and harmonic (synchronous) ventricular electrical activation is essential for better left ventricular systolic function. Intraventricular conduction abnormalities, such as left bundle branch block due to artificial cardiac pacing, lead to electromechanical "dyssynchronopathy" with deleterious structural and clinical consequences. The aim of this review was to describe and improve the understanding of all the processes connecting the several mechanisms involved in the development of artificially induced ventricular dyssynchrony by cardiac pacing, most known as pacing-induced cardiomyopathy (PiCM). The chronic effect of abnormal impulse conduction and nonphysiological ectopic activation by artificial cardiac pacing is suspected to affect metabolism and myocardial perfusion, triggering regional differences in the activation/contraction processes that cause electrical and structural remodeling due to damage, inflammation, and fibrosis of the cardiac tissue. The effect of artificial cardiac pacing on ventricular function and structure can be multifactorial, and biological factors underlying PiCM could affect the time and probability of developing the condition. PiCM has not been included in the traditional classification of cardiomyopathies, which can hinder detection. This article reviews the available evidence for pacing-induced cardiovascular disease, the current understanding of its pathophysiology, and reinforces the adverse effects of right ventricular pacing, especially right ventricular pacing burden (commonly measured in percentage) and its repercussion on ventricular contraction (reflected by the impact on left ventricular systolic function). These effects might be the main defining criteria and determining mechanisms of the pathophysiology and the clinical repercussion seen on patients. [ABSTRACT FROM AUTHOR]

Manufacturers are increasingly focusing not only on their product offering, but also on services. They want to create customer value and protect their competitive edge in the marketplace. The transition process from product-to-service-centric logic is referred to as servitization. Despite a large and growing body of academic literature, there are still some gaps in research in the field of financial benefits. The aim of the paper is to study if small and medium-sized manufacturers perceive the financial benefits of providing smart services. The research was carried out with the respondents from small and medium-sized companies that are representatives of the electrical industry. [ABSTRACT FROM AUTHOR]

The objective of this work was to evaluate the effect of partial replacement of soil by different percentages of coconut fiber powder in the manufacture of soil–cement bricks. The reference mix ratio of 10:1 (soil:cement) in volume was used for the manufacture of bricks, in addition to the partial replacement of soil mass by 5, 10, and 15% of coconut fiber. The characterization of the raw materials was performed with the analysis of the granulometry, together with technological tests, such as mechanical compressive strength and water absorption. As a result, it was observed that the soil has 34.30% clay and 62.80% sand, characterizing a sandy-clay soil type and the coconut fiber powder was characterized as a fine aggregate. The mechanical compressive strength tests showed a decrease in their average values according to the increase in the incorporation of coconut fiber into the bricks. It was concluded that the results of the mechanical compressive strength and some of the water absorption are in disagreement with the Brazilian technical standard. This conclusion corroborates other studies that show the difficulty in standardizing reference mixtures and working with soil, which is a highly heterogeneous material. [ABSTRACT FROM AUTHOR]

Copyright of Revista Portuguesa de Enfermagem de Reabilitação is the property of Associacao Portuguesa dos Enfermeiros de Reabilitacao (APER) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this paper we consider, on one hand, a differentiated Cournot model, and, on the other hand, a differentiated Bertrand model, when one of the firms engages in an R&D process that gives an endogenous cost-reducing innovation. The aim of the present paper is two-fold. The first is to study the licensing of the cost-reduction by a per-unit royalty and a fixed-fee in these Cournot and Bertrand models. The second is to do a direct comparison between Cournot model and Bertrand model. We analyse the implications of these types of licensing contracts over the R&D effort, the profits of the firms, the consumer surplus and the social welfare. We show that some previous results for two-part tariff licensing are not robust, in the sense that they can be not true for just either a per-unit royalty contract or a fixed-fee contract. Furthermore, by using comparative static analysis, we conclude that the degree of the differentiation of the goods assumes a great importance in the results. We also discuss the optimal licensing, meaning that which licensing method is preferred, in each of the duopoly models considered. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the maximum strength and the maximum aperture supported by mini-implant screws of three different diameters in an in vitro rapid maxillary expander model. Materials and Methods: Fifteen appliances were mounted in artificial bone polyurethane blocks. In each appliance, a Hyrax expander anchored by four mini-implant screw sets of three different diameters were divided into: group 1 (n = 5), 1.8-mm-diameter screws; group 2 (n = 5), 2.0-mm-diameter screws; and group 3 (n = 5), 2.2-mm-diameter screws. All sets (bone blocks + expander + four mini-implants) were inserted into a customized and standardized device that simulated a mid-palate disjunction. The expanders were activated to mechanically test the insertion of the mini-implant into the devices until breakage or deflection of screws occurred. The number of activations, the maximum supported strength, and the maximum expander aperture values until failure were recorded for each group. Data were subjected to a Student t test at a significance level of 5%. Results: There were no significant differences between the groups regarding the number of activations up to the maximum supported strength. The expander achieved aperture values where differences were slightly significant just between groups 1 and 2 (P = .048). There was a significant difference between groups 1 and 3 regarding the maximum supported load (P = .039). Conclusion: Regardless of the mini-implant screw diameters, the expander device used in this anchorage system model withstood strengths and aperture rates beyond those that may be required during clinical rapid maxillary expansion. [ABSTRACT FROM AUTHOR]

Copyright of Arquivos de Neuro-Psiquiatria is the property of Thieme Medical Publishing Inc. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Aim: The road network is increasing globally but the consequences of roadkill on the viability of wildlife populations are largely unknown. We provide a framework that allows us to estimate how risk of extinction of local populations increases due to roadkill and to generate a global assessment that identifies which mammalian species are most vulnerable to roadkill and the areas where they occur. Location: Global. Time period: 1995–2015. Major taxa studied: Terrestrial mammals. Methods: We introduce a framework to quantify the effect of roadkill on terrestrial mammals worldwide that includes three steps: (a) compilation of roadkill rates to estimate the fraction of a local population killed on the roads, (b) prediction of population risk of extinction based on observed roadkill rates (for a target group of species of conservation concern and non‐threatened species with high roadkill rates), and (c) global assessment of vulnerability to roadkill for 4,677 terrestrial mammalian species estimated using phylogenetic regression models that link extinction risk to demographic parameters. Results: We identified four populations among the 70 species in the target group that could become extinct in 50 years if observed roadkill levels persist in the study areas: maned wolf Chrysocyon brachyurus (Brazil), little spotted cat Leopardus tigrinus (Brazil), brown hyena Hyaena brunnea (Southern Africa) and leopard Panthera pardus (North India). The global assessment revealed roadkill as an added risk for 2.7% (n = 124) terrestrial mammals, including 83 species Threatened or Near Threatened. We identified regions of concern that have species vulnerable to roadkill with high road densities in areas of South Africa, central and Southeast Asia, and the Andes. Main conclusions: Our framework revealed populations of threatened species that require special attention and can be incorporated into management and planning strategies informing road managers and conservation agencies. [ABSTRACT FROM AUTHOR]

Background: Facial care treatments have grown a remarkable demand for effective and minimally invasive techniques with fast recovery time. Plasma technology is a nonsurgical alternative technique for skin rejuvenation. Aims: We assessed patient satisfaction and symptoms after upper eyelid blepharoplasty with plasma technology. Patients/Methods: Observational study including 16 patients submitted to upper eyelid blepharoplasty using plasma technology to treat dermatochalasis. Patient satisfaction, symptoms, and quality of life were assessed using 2 questionnaires at follow‐up days 7 and 30. Also, the answers were correlated with age, Fitzpatrick skin type, and quantity of eyelid skin treated with plasma. Results: All 16 patients were treated and completed the survey. Fourteen (87.5%) were female, and the mean age was 50.5 years. Physical appearance was the most relevant factor impacting on quality of life at first week postoperative. Regarding satisfaction with results, most patients stated higher level of satisfaction at day 7 follow‐up analysis (P =.038). Less impact on quality of life and higher satisfaction was associated with eyelid‐treated area (P =.044 and P =.036) and Fitzpatrick skin type (P =.043) at 7 and 30 days after procedure, respectively. Eyelid edema and itching were the symptoms most reported at 7 and 30 days, respectively. Conclusions: Upper blepharoplasty with plasma is a minimally invasive treatment with low impact on quality of life. However, overall patient satisfaction is questionable when considering less willing of undergoing procedure again and decreased expectation with results over postoperative period. Symptoms are reported mainly at the first week after procedure. [ABSTRACT FROM AUTHOR]

This work addresses the synthesis of a multi-band frequency selective surface (FSS) through bioinspired computing and a general regression neural network (GRNN). This hybrid computational method, which utilizes the multi-objective cuckoo search algorithm combined to a GRNN, determine the best physical dimensions of the FSS in order to achieve a multi-band filtering at the 2.4, 3.5 and 5.8 GHz spectrums. Therefore, the results are to be applied to aid the propagation of Wi-Fi, WLAN, WiMAX and future sub-6 GHz 5G systems. The resonant frequencies were measured and a -10 dB cutoff value has been considered for the transmission coefficient. The triple rectangular loop conductor geometry of the device is printed upon a glass epoxy (FR-4) substrate. Measurements were made for different wave incidence angles, from 0° up to 45°, to demonstrate how signal incidence would affect the device's functioning. The agreement between simulated and measured data display satisfactory results. [ABSTRACT FROM AUTHOR]