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Global demographic trends have signaled a growing need for biomedical implants such as artificial hips, dental implants, spine screws, coronary stents, and heart pacemakers. The reliability of a manufactured implant can be primarily ensured in terms of its surface integrity, dimensional accuracy, and biocompatibility. In the case of subtractive manufacturing of an implant, the required surface finish and complex geometrical features take the machining to a whole new level. However, the machining of mostly metallic biomaterials such as titanium and its alloys has always been challenged by their poor machinability. In this regard, the latest research has reported the outperformance of cryogenically treated non-coated and coated cutting tools and hybrid cooling environments, which resulted in a noteworthy improvement of machinability and biocompatibility of difficult-to-machine biocompatible materials. Therefore, the present research aimed to enhance the surface integrity and in vitro biocompatibility of Ti-6Al-4V alloy by using AlTiN coated solid carbide end mill in untreated and cryogenically treated condition with wet (using traditional cutting fluid as coolant), cryo (using liquid nitrogen as coolant), and hybrid-lubri-coolant (using a combination of cutting fluid and liquid nitrogen as coolant). The experimental findings were analyzed by RStudio software. The results reported that untreated end mill with cryo-lubri-coolant (C-LC) and cryo-treated end mill with hybrid-lubri-coolant (H-LC) achieved the targeted objectives of this research. However, the cryo-treated end mill with H-LC outperformed the untreated end mill with C-LC and produced better surface characteristics, confirmed by a morphological study of the H-LC-milled surface and cryo-treated end mill. The finding of the in vitro studies confirmed that the H-LC-milled surface exhibited superior biocompatibility and promoted the adhesion, growth, and proliferation of adipose-derived stem cells (ADSCs).

This study aimed to develop an optimal set and size model of bioenergy facilities using a GIS framework. Data from sugarcane plantations were used to create case scenarios. Spatial analysis was accomplished by applying a two-phase approach: identification of suitable zones to locate bioenergy facilities and identification of ideal areas. These analyses led to a location-allocation model, using Maximize Capacitated Coverage option, in order to assign sugarcane supply areas to potential bioenergy facilities. Nine themes, as well their respective weights, generated by AHP, were used to create a visual depiction of potential sites. This layer was reclassified into five categories, using Natural Breaks (Jenks) method. Various scenarios of bioenergy plants installation were simulated. Around 50% of the area is unsuitable for bioenergy plants. A total of 1,737 potential sites were detected for implanting bioenergy plants. The best regions to locate bioenergy plants were peripheral areas. Cumulative biomass transportation distances dramatically reduce as the number of facilities increases. There is a reduction of 31% in total and average distances when comparing a 4-plant scenario with a single plant scenario. Proposed scenarios can support decision making with different numbers of bioenergy plants. Proposed methodology can be adapted to areas of other countries.

Resumo Introducao A associacao de anestesicos locais (AL) com bloqueadores neuromusculares (BNM) na pratica clinica e a possibilidade de interacao entre esses farmacos tem sido investigadas. Objetivo Avaliar, em modelo experimental, o efeito da lidocaina e da bupivacaina racemica na transmissao neuromuscular e sua influencia no bloqueio neuromuscular produzido pelo atracurio. Metodo Ratos machos da linhagem Wistar, peso entre 250 e 300 g. A preparacao foi feita de acordo com a tecnica proposta por Bulbring. Grupos (n = 5) de acordo com o farmaco em estudo: lidocaina 20 μg.mL‐1 (Grupo I); bupivacaina racemica 5 μg.mL‐1 (Grupo II); atracurio 20 μg.mL‐1 (Grupo III); atracurio 20 μg.mL‐1 em preparacao previamente exposta a lidocaina 20 μg.mL‐1 e bupivacaina racemica 5 μg.mL‐1, Grupos IV e V, respectivamente. Foram avaliados: 1) A amplitude das respostas do hemidiafragma a estimulacao indireta antes e 60 minutos apos a adicao dos farmacos; 2) Os potenciais de membrana (PM) e os potenciais de placa terminal em miniatura (PPTM). Resultados Os AL, isoladamente, nao alteraram a amplitude das respostas musculares. Com o uso previo dos AL, o bloqueio neuromuscular (%) do atracurio foi 86,66 ± 12,48 e 100, respectivamente, com diferenca significante (p = 0,003) em relacao ao produzido pelo atracurio isoladamente (55,7 ± 11,22). Nao alteraram o PM. A lidocaina inicialmente aumentou a frequencia dos PPTM, seguido de bloqueio; com a bupivacaina, o bloqueio foi progressivo. Conclusao A lidocaina e a bupivacaina racemica apresentaram efeito pre‐sinaptico expresso por alteracoes nos PPTM, podem justificar a potencializacao do bloqueio neuromuscular produzido pelo atracurio.

Medication-related osteonecrosis of the jaws (MRONJ) is difficult to treat, therefore, prevention would be the ideal clinical approach. This study evaluated the effectiveness of antimicrobial photodynamic therapy (aPDT), mediated by butyl toluidine blue (BuTB) in the prevention of MRONJ-like lesions after tooth extraction in rats.Twenty-eight senescent female rats were distributed in groups: VEH and VEH-aPDT, treated with vehicle, ZOL and ZOL-aPDT, treated with 100 µg/Kg of zoledronate, both treatments every three days over seven weeks. After three weeks from the commencement of treatment, the mandibular first molar was extracted. For the VEH and ZOL groups, no local treatment was performed, while with the VEH-aPDT and ZOL-aPDT groups, photodynamic treatment was carried out at 0, 2, and 4 days after extraction. For aPDT, 500μl of BuTB solution was deposited on the dental extraction site (0.5 mg/ml; 60s), followed by irradiation with low-level laser (InGaAIP; 660nm; 35mW; 74.2J/cm²; 60s). After 28 postoperative days, euthanasia was performed. The hemimandibles were processed to: 1) histological analysis of tissue repair; 2) histometric analysis of the percentage of newly formed bone tissue (PNFBT) and percentage of non-vital bone tissue (PNVBT); 3) immunohistochemical analysis for tartrate-resistant acid phosphatase (TRAP).The ZOL and ZOL-aPDT groups showed less TRAP-positive cells when compared with VEH and VEH-aPDT. The ZOL group demonstrated great compromise in the tissue repair process, consistent with MRONJ-like lesions. VEH, VEH-aPDT and ZOL-aPDT presented a favorable tissue repair process. PNFBT in the ZOL group was lower than in the VEH, VEH-aPDT and ZOL-aPDT groups, whereas PNVBT in the ZOL group was higher than in the VEH, VEH-aPDT and ZOL-aPDT groups.aPDT mediated by BuTB prevented the occurrence of MRONJ-like lesions after tooth extraction in rats.

Stem volume is a key attribute of Eucalyptus forest plantations upon which decision-making is based at diverse levels of planning. Quantifying volume through remote sensing can support a proper management of forests. Because of limitations on spaceborne optical and synthetic aperture radar sensors, this study integrated both types of datasets assembled using support vector regression (SVR) to retrieve the stand volume of Eucalyptus plantations. We assessed different combinations of sensors and a minimum number of plots to develop an SVR model. Finally, the best SVR performance was compared with other analytical methods already tested and in the literature: multilinear regression, artificial neural networks (ANN), and random forest (RF). Here, we introduce a test for comparative analysis of the performance of different methods. We found that SVR accurately predicted stem volume of Brazilian fast-growing Eucalyptus forest plantations. Gaussian radial basis was the most suitable kernel function. Integrating the optical and L-band backscatter data increased the predictive accuracy compared to a single sensor model. Combining NIR-band data from ALOS AVNIR-2 and backscatter of L-band horizontal emitted and vertical received (HV) electric fields from ALOS PALSAR produced the most accurate SVR model (with an R2 of 0.926 and root mean square error of 11.007 m3/ha). The number of field plots sufficient for model development with non-redundant explanatory variables was 77. Under this condition, SVR performed similarly to ANN and outperformed the multiple linear regression and random forest methods.

Duplex stainless steels (DSS) show good mechanical properties, wear, corrosion resistance and fatigue strength. In order to decrease operational costs in paper and pulp industry, DSS is employed through weld overlay coatings on mild or low carbon steel components. In this work, the aim was to evaluate the DSS weld overlay properties obtained through deposition of ER 2209 duplex stainless steel alloy on a mild steel plate (ASTM A 516 Gr 60). The deposition was performed through GMAW/CMT welding process. The coatings were deposited using four heat inputs: 0.53, 1.01, 1.27 and 1.74 kJ/mm. Moreover, microstructural characterization by optical microscopy showed that heat input influences ferrite/austenite phase balance. Secondary austenite that precipitates due to the welding process in DSSs are Widmanstatten austenite (WA), grain boundary austenite (GBA), partially transformed austenite (PTA) and intragranular austenite (IGA). The amount of secondary austenite increases with welding energy input. The secondary austenite improves abrasive wear resistance while corrosion resistance is the lowest when welding energy is 1.74 kJ/mm.

A thermochemical study of [SbCl3(L)] and [BiBr3(L)] complexes, wherein L is 2,2′-bipyridine (bpy) or 1,10-phenanthroline (phen), was performed by calorimetric measurements in solution. The complexes were synthesized and characterized by elemental analysis, FTIR spectroscopy and thermal analysis. From the enthalpies of dissolution of the complexes, salts and ligands in combination with auxiliary thermodynamic data, some thermochemical parameters of the complexes were determined by use of thermochemical cycles. Theoretical study on the complexes was performed using M06-2X/def2-TZVPP method. Donor-acceptor bond energies were obtained taking into account reorganization energies of the fragments. Our findings suggest that both the reorganization energy of the acceptor metal trihalide MX3 (113–136 kJ · mol−1) and the rigidity of the phen govern the dissociation energy of the complexes. The theoretical results indicated that the chemical stabilities of the complexes decreases in order [BiBr3(phen)] > [SbCl3(phen)] > [BiBr3(bpy)] > [SbCl3(bpy)], agreeing with the experimental enthalpies of coordination in solid state.

Herein, we describe the synthesis and characterizations of 2,4,6-tris(thiomorpholine)-1,3,5-triazine, 2,4,6-tris(piperazine)-1,3,5-triazine and their new Sb(III) and Bi(III) complexes. Characterizations of the ligands and complexes were carried out by elemental analysis, thermogravimetric analysis (TGA), and spectroscopic methods such as infrared (IR), 1H and 13C nuclear magnetic resonance (NMR), and single crystal X-ray. Theoretical vibrational frequencies and 1H and13C NMR chemical shifts of free ligands as well as their Sb(III) and Bi(III) complexes have been calculated using density functional theory (DFT/B3LYP and M06-2X) methods. Our theoretical results matched the corresponding experimental data and helped with the interpretation of the IR and 1H and 13C NMR spectra. The antimicrobial in vitro studies were carried out against bacterial species Staphylococcus aureus and fungal species Candida albicans, Candida tropicalis, and Candida krusei by the microdilution method. The preliminary antimicrobial evaluations indicated that Sb(III) complexes showed moderate activities against all tested strains of bacterial and fungal with minimum inhibitory concentration (MIC) in range of 512–1024 μg mL−1.

[EN] The sintering, crystallization and mechanical behavior of three glass compositions in the SiO-AlO-MgO/ZnO system were investigated. Partial substitution of MgO by ZnO causes a decrease in T, a slight increase in the crystallization temperature and improves sinterability. Cordierite and enstatite were crystallized in bulk glasses heat treated at 1000 °C. Addition of ZnO resulted in the crystallization of cordierite, willemite and gahnite for the heat treated bulk glasses and cristobalite, enstatite, gahnite and willemite for the sintered glass powders. The first phase to crystallize is the β-quartz solid solution at 850−900 °C for all compositions. The glass and glass-ceramic with ZnO had the lowest hardness and elastic modulus. There was no variation of fracture strength with composition. The glass-ceramic with ZnO had a similar wear resistance in comparison to the composition with higher MgO content., The authors acknowledge the financial support from CAPES PDSE (grant n°88881.132583/2016-01), FINEP, CNPq, Fundação Araucária, UGF from Brazil for funding laboratory infrastructure and are thankful to ICV-Madrid-Spain and C-LABMU/UEPG for the use of the characterization facilities

Eradication of implant centered infection remains a clinical challenge as the biofilm formation protects the bacteria. Bactericidal surfaces represent an effective tool in the prevention of biofilm formation, although the bactericidal agent cannot be cytotoxic to assure a proper implant osseointegration. Boron is a trace element, beneficial to bone formation and bactericidal against several strains. In this research, a boron containing coating was obtained on a titanium surface by plasma electrolytic oxidation. Its bioactivity and bactericidal activity were evaluated and compared to a boron-free coating. Boron presence has not changed the morphology, roughness and crystalline structure of the coating. Adipose derived stem cells culture revealed the coating biocompatibility and its bactericidal activity was assessed against Staphylococcus aureus and Pseudomonas aeruginosa. This study revealed for the first time the bactericidal activity of a biocompatible boron doped TiO2 coating.

Metallic implants are susceptible to bacterial colonization even years after the implantation impairing the osseointegration process. The treatment of a colonized implant is highly demanding, and in most cases implant replacement is the only effective solution. To avoid the bacterial attachment and proliferation, bactericidal coatings are proposed as a long-term prevention tool. Those coatings must assure a bactericidal activity for a long period and cannot induce cytotoxic responses in eukaryotic cells. Among all the bactericidal agents, Zinc is one of the most investigated due to its broad bactericidal activity spectrum and its stimulatory effect on bone formation. The aim of this study is to obtain a titanium oxide coating containing Zinc and evaluate its bactericidal activity, cytotoxicity and ion release profile. The coating was obtained by Plasma Electrolytic Oxidation (PEO) on commercially pure titanium grade 4 at 350 V for 60 s. Samples were divided in two groups; the reference group was obtained in a base electrolyte containing calcium acetate and calcium glycerophosphate (called CaP group). The experimental group had Zinc acetate added as a Zinc source to the base electrolyte (called Zn-CaP group). The surface was characterized by Scanning Electron Microscopy (SEM) and X-ray Photoelectron Spectroscopy (XPS), while the ion dissolution was evaluated by Inductively Coupled Plasma - Atomic Emission Spectroscopy (ICP-AES). The bactericidal activity was determined against Staphylococcus aureus by fluorescence microscopy using a live/dead viability kit. The cytotoxicity against eukaryotic cells was evaluated using adipose derived stem cells (ADSC) using the lactate dehydrogenase (LDH) assay. Zinc, Calcium and Phosphorous were incorporated to the titanium oxide coating and no changes on the coating structure and morphology were observed by the addition of Zn to the electrolyte. ICP-AES results show the coatings released Ca, P and Z ions after 28 days of immersion in DI water. The ICP-AES profile suggests the ion release reach an equilibrium state after 7 days of immersion. The Zn-CaP coating presented bactericidal activity against S. aureus, showing a higher number of dead bacteria after 6 h of incubation and a lower number of living bacteria after 24 h compared to the CaP group. No cytotoxic effect was observed against ADSC by the presence of Zn on the coating, indicating the Zn-CaP coating has a potential to prevent bacterial colonization in metallic implants.

Over the past few years, many sectors such as energy generation, industry, domestic supply, and agriculture have encountered serious environmental problems due to the lack of rainfall. Thus, the purpose of this paper is to review the current methodology of royalties distribution from Itaipu hydroelectric plant. In the proposed approach, two criteria were considered to establish the division of Itaipu royalties: (1) the relative percentage of the water flow in the generation of electricity and, (2) the relative percentage of the drop in the height of water. 62 hydroelectric plants were evaluated in this study. In 52 plants the water flow was the factor that most contributed to the generation of electricity. In 2013, 346 municipalities benefited the Itaipu royalties. With the proposed methodology, 1,327 municipalities will receive the resource, what would increase the revenue of each of these municipalities by, on average, US$ 87,436.91 per year. The methodology presented herein proposes a reduction in the environmental disparity that now exists in Brazil, through improvement to Government instruments and environmental policies. The distribution of royalties throughout the watershed can provide additional resources to support payment programs for environmental services at the state and municipality levels.

Background The incidence of anemia in kidney transplantation patients (KTPs) is very common and seems to be associated with the reduction in both renal function and physical exercise tolerance. The purpose of the present study was to compare biochemical markers of anemia and renal function of physically active and sedentary KTPs. Method Serum hemoglobin (Hb), hematocrit (Hct), and serum creatinine (used to derive estimated glomerular filtration rate [eGFR]) were obtained from the medical records of 18 KTPs assisted at the Center for Prevention of Kidney Diseases of the Federal University of Maranhao Hospital. The physically active transplant patients (group 1) included 7 men and 2 women, aged 49 ± 14 years who participated for at least 6 months on a supervised physical exercise program (SPEP) (2 to 3 times a week, 90-minute sessions) and the sedentary counterparts (group 2) of 2 men and 7 women, aged 37 ± 15 years. Results Group 1 presented higher values of Hb (14.2 ± 2.6 vs 10.7 ± 0.6 g/dL; P = .003), Hct (41.6% ± 7.0% vs 32.3% ± 1.4%; P = .004), and eGFR (64.4 ± 19.4 vs 39.3 ± 19.7 mL/min/1.73 m2; P = .015) when compared with group 2. There was a positive and significant correlation between Hb and eGFR (r = 0.528; P = .024), and between Hct and eGFR (r = .509; P = .031). Conclusions Our results suggest that regular physical activity seems to improve the biochemical markers of anemia and also the renal function of KTPs, and these patients should be advised to participate in SPEP.

The recent crisis in some euro area countries is intensively fueling the political and economic policy debate about the effectiveness of the applied adjustment programs. This paper aims to contribute to explaining why the results of these programs could be different across countries, flagging the crucial role of exports. In view of recent economic literature about substitution between domestic and foreign sales, helping exports when domestic demand is adjusting, this paper uses panel data techniques to assess the role of the export structure in explaining this substitution effect in the euro area countries. Building a novel indicator for product concentration, the results suggest that domestic demand developments are more relevant to explaining exports in countries with a lower product concentration index (that is, more diversified exports). This contributes to explain why euro area countries under stress registered different economic performance, in particular the clearly less favorable behavior of Greece, where exports structure is concentrated more strongly in some goods and services than in other euro area countries. With different export behavior the final evaluation of the Greek adjustment would be certainly different. These results suggest that export structure should be taken into consideration when designing or evaluating this type of adjustment programs.

The surface modification via subtractive manufacturing intends to localize the desired properties on the produced surface during the machining. In the case of miniaturized components, the powder mixed-micro-electric discharge machining (PM-μ-EDM), a potential variant of EDM, can achieve superior microfeatures such as dimensional accuracy and surface integrity, and a noteworthy surface modification on the hard and tough materials such as titanium and nickel alloys. Besides, the increasing demands for microfabricated devices used in tissue engineering and therapeutics delivery encourage their production with improved surface characteristics and biocompatibility. The superelastic nickel‑titanium alloy (Nitinol) has recently emerged as one of the most desirable biomaterials primarily in the vascular and prosthetic applications. However, the microfabrication followed by surface modification of Nitinol by the PM-μ-EDM has been rarely recorded. Hence, this research aimed to modify the Medical-grade Ni55.6Ti44.4 alloy surface with the least machining time and dimensional deviation using zinc PM-μ-EDM. A comparative study between the μ-tool electrodes (copper and brass) and Zn powder particle concentrations (PPCs: 0, 2, 4, 6, 8, and 10 g/l) revealed that the copper μ-tool electrode in association with 6 g/l PPC, could achieve the most improved machinability and modified layer on the Ni55.6Ti44.4 alloy surface. A field emission scanning electron microscope (FESEM) and energy-dispersive X-ray spectroscopy (EDS) investigated the dimensional, morphological, and compositional features of the modified Ni55.6Ti44.4 alloy surface and reported significant improvements. The X-ray diffraction (XRD) analysis of the modified surface detected a remarkable impact of the thermally induced variations on the crystalline phases of Ni55.6Ti44.4 alloy. Further, the lactate dehydrogenase (LDH) and CellTiter-Blue assays determined improved cytocompatibility characteristics and Drop Shape Analyzer (DSA) ascertained the hydrophobicity of the modified Ni55.6Ti44.4 alloy surface.

This paper reports on the development of a mathematical methodology for analyzing the error propagation, also called uncertainty, with regards to the determination of the complex stiffness modulus for asphalt mixes. Experimental data were taken as reference, considering two-point bending tests carried out upon French methodology standardized criteria. The Huet-Sayegh rheological viscoelastic model was parameterized by using the computerized tool Viscoanalyse Beta. The model developed was analytically deducted, based on partial derivatives, aiming at to discretize the influence of each variable from complex modulus rheological behavior, represented graphically by the Cole–Cole plan. Error levels of 2.5%, 5.0%, 7.5% and 10.0% were statistically simulated to verify the adherence between the experimental data and the rheological model mentioned. The results obtained indicate the efficiency of the methodology developed for establishing error propagation analysis between theoretical and experimental basis, reaching close adherence for maximum error levels of 10.0% and 5.0%, respectively.

Splenic artery aneurysms (SAA) are more frequent in women and have a high rupture risk during pregnancy, with catastrophic outcomes. It is advisable to treat these aneurysms in pregnant and fertile women, whatever their diameter, given their increased risk for rupture. There are several therapeutic approaches: endovascular surgery using coil embolization or stent graft coverage; laparoscopic or open surgical resection with arterial reconstruction and ligation followed by splenectomy when necessary. This paper aims to report the successful treatment of SAA in second-trimester pregnant women using a laparoscopic approach with aneurysm resection and arterial reconstruction. This is a unique report of a minimally invasive approach with arterial reconstruction in a pregnant woman, thus reducing the risk of spleen infarction and potentially avoiding splenectomy.

Degenerative diseases, such as osteoarthritis, osteoporosis and accidents can cause hip problems and injuries leading to a necessary hip prosthetic replacement. Acetabular and femoral prosthesis parts, consisting of special alloys of steel and titanium, are fixed to the bones using orthopedic cement based on poly(methyl methacrylate) (PMMA). With aim of improving implant material properties in terms of compatibility with the human body, were evaluated the bioactive responses of ISO 5832-9 steel and Ti6Al4V alloy coated with electrospun PMMA nanofibers. The electrospinning technique is widely used due to the possibility of easily producing fibers within nano or micrometric scale using a low cost, simple experimental apparatus that allows large-scale production. In this work the metallic substrates were submitted to surface pretreatments with sanding alone or in combination with acid etching. After deposition by electrospinning, the surfaces were characterized morphologically, chemically, and for roughness. PMMA fibers were obtained, with nanometric diameter, forming a uniform and homogeneous layer over both metal sample surfaces without appreciable differences in adhesion. The sanded surface, being a one-step process, was chosen for the next step. Fibroblasts were grown on the sample surfaces, for seven days, to determine biocompatibility. Electrospinning Induced Surface Activation (EISA) was used to incorporate hydroxyl radicals into the PMMA chain to produce hydroxylated PMMA, that was later redissolved and electrospun into nanofibers. Both samples (PMMA and PMMA-OH nanofibers) resulted in good cell adhesion properties. However, a denser cell monolayer was observed on the hydroxyl-terminated sample, indicating better cell-material interaction. Hydroxyl (OH) functionalized molecules can regulate cell behavior acting as a linker capable of reacting with proteins, thus accelerating cell growth, migration, differentiation, synthesis of extracellular matrix components, and tissue morphogenesis. By a simple two-step methodology it was possible to obtain electrospun hydroxyl functionalized bioactive PMMA nanofibers deposited on metallic implant samples with an increased cell response.

For countries dependent on hydroelectricity, water scarcity poses a real risk. Hydroelectric plants are among the most vulnerable enterprises to climate change. Investing in the conservation of the hydrographic basin is a solution found by the hydropower sector. Given the importance of the Itaipu plant to the energy matrix of Brazil and Paraguay, the aim of this study is to review the current distribution of royalties from Itaipu, using the hydrographic basin as a of criterion of analysis. Approximately 98.73% of the Itaipu basin is in Brazil. The flow contributes 99% of the total electricity generated there, while the drop height of the water contributes only 1%. Under the current policy, royalties are shared equally between Brazil and Paraguay. In the proposed approach, each country would receive a percentage for their participation in the drop height and water flow in the output of the turbines, which are intrinsic factors for electricity generation. Thus, Brazil would receive 98.35% of the royalties and Paraguay, 1.65%. The inclusion of the hydrographic basin as a criterion for the distribution of royalties will promote more efficient water resource management, since the payment will be distributed throughout the basin of the plant. The methodology can be applied to hydroelectric projects worldwide.

The provision of raw water to urban supply systems is a global endeavor, and a great challenge to water resource managers of large metropolitan regions. A sustainable supply requires the integrated management of water quantity and quality, as well as the system’s adaption to land use and climate changes (e.g., deforestation, droughts). The available water security models inform about the current security status of a system based on the assessment of quantity, quality and adaption indicators. But they barely include risk variables in the analysis, which could help to improve the security assessment considering the historical records of indicators or their future projections. In the present study, a new method is developed that couples a security assessment based on the rating of pressure indicators acting on a watershed, such as water demand, ordinary and accidental contaminants, droughts, and environmental settings (e.g., share of forest cover), with a risk assessment based on pressure properties such as severity, occurrence and detectability. The method is framed in the “Failure Mode and Effects Analysis”, and was applied to the Rio das Velhas system that supplies a portion of Belo Horizonte metropolitan region (Minas Gerais, Brazil) with >4 million inhabitants. The results exposed unacceptable risks for water demand, ordinary contaminants and droughts, because of their high severity and frequency. The water demand risks were explained by data on current (2019) water scarcity and population growth projections (until 2036) that are likely to raise water consumption. The ordinary contaminant risks were deduced from information on current deviations of water quality parameters (e.g., dissolved oxygen, turbidity) from legal thresholds, and records (since 2007) of stream water contamination by untreated domestic effluents. Finally, the drought risks were explained by information on the persistence of stream flows below a legal reference flow, coupled with the identification of many (23) dry years in the available stream flow record (48 years). Overall, the proposed model was efficient in the evaluation of water security risk in the basin. The results obtained for the study area help to act on the required mitigation through prioritization of risk attenuation. Given the simplicity and modest data requirements, the method is helpful to decision makers and suited for replication in other similar regions around the globe.

When constructing a new railway line, its long length means there are significant financial implications associated with determining the geodynamic ground properties. Therefore, this paper presents recommendations to optimize the efficiency and depth of such a geotechnical site investigation. Firstly, a numerical analysis is performed to investigate the effect of soil layering, soil stiffness and track bending stiffness on critical velocity. It is shown that each of these variables play an important role, however for most practical cases, only the top 8 m of soil is influential. Track dynamics are rarely affected by soil properties at depths below this, meaning this is the maximum required depth of soil investigation. Using this knowledge, a hybrid experimental-analytical methodology is presented, based on a geophysical Spectral Analysis of Surface Waves (SASW) experimental setup to compute the ground dispersion curve and an analytical model to compute the track dispersion curve. The experimental and analytical results are combined directly, to accurately compute the critical velocity. This approach is attractive because: 1) SASW tests are typically accurate to ≈8 m (when using a mobile exciter) thus matching the required depth needed for critical velocity computation, 2) soil property uncertainties are inherently accounted for, 3) the uncertainties associated with SASW inversion are avoided. The approach is attractive when constructing new railway lines and upgrading the speed of existing lines because it can potentially yield site investigation cost savings. In-situ field work is performed to show the practical application of the technique., This research was financially supported by: Project POCI-01-0145-FEDER-007457–CONSTRUCT–Institute of R&D InStructures and Construction funded by FEDER funds through COMPETE2020– Programa Operacional Competitividade e Internacionalização (POCI)–and by national funds through FCT–Fundação para a Ciência e a Tecnologia; Project POCI-01-0145-FEDER-029577–funded by FEDER funds through COMPETE2020 – Programa Operacional Competitividade e Internacionalização (POCI), national funds (PIDDAC) through FCT and the Leverhulme Trust (PLP-2016-270). This work was partially carried out under the framework of In2Track2, a research project of Shift2Rail. The financial support provided by University of Leeds Cheney Award Scheme is also appreciated.

In this work, three plasma-enhanced techniques have been used to deposit Diamond-like Carbon coatings (DLCs), as follows: HiPIMS, PECVD, and PIID. The DLCs deposition was on nitrided and non-nitrided steel substrates. In the DLCs deposited by HiPIMS and by PECVD processes, an adhesion layer of Ti/TiN and Ti/TiN/TiC, respectively, was deposited using a W hot filament. In the PIID process, a SiCx interlayer was grown out of tetramethylsilane gas before DLC deposition. Subsequently, the DLCs coated systems were characterized by SEM/EDS, Raman Spectroscopy, instrumented hardness, adhesion, and tribological behavior. Raman characterization revealed that DLC deposited by PECVD presented the lowest ID/IG ratio, meaning the highest amount of sp3 bonding, consequently, was the hardest coating. Adhesion probed by a scratch test revealed that the DLC deposited by PECVD showed gross spallation, exposing the Ti/TiN/TiC adhesion layer. On the other hand, the DLCs deposited by HiPIMS and PIID showed wedging spallation, as the primary adhesive failure mode. The DLC that presented the best tribological behavior was the one deposited by PECVD due to its highest H/E ratio.

Bordetella pertussis infection remains a serious potential health risk to infants, specially in those too young to be vaccinated. Over the recent years, numerous sources highlighted a widespread resurgence, making it, again, a challenging disease. Globally, pertussis is ranked among the 10 leading causes of childhood mortality. This review summarizes the most recent literature and will address the most important aspects that pediatricians and neonatologists must be familiar with, when treating a newborńs pertussis infection.

Biomass estimation plays an important role in forest management being applied in most carbon sequestration studies, assessment of forest succession, conservation of natural resources, quantification of nutrient cycling, energy planning where forest biomass is used as primary fuel for power generation and harvest planning and stock management in pulp industry. Using data from Advanced Visible and Near Infrared Radiometer type 2 (AVNIR-2) and Phased Array type L-band Synthetic Aperture Radar (PALSAR) sensors onboard Advanced Land Observing Satellite (ALOS), above-ground biomass (AGB) estimates were generated via artificial neural networks for a eucalyptus planting area in Minas Gerais State, Brazil. With 206 inventory plots, computed coefficient of determination between AGB estimates and observed values within validation sample was 0.95. Relative root mean square error was 2.87% with errors ranging from −8% to 4%. These results demonstrated artificial neural networks higher performance in modeling eucalyptus biomass based on Multispectral and SAR data over previous study, in which multiple linear regression method was applied in the same dataset, achieving R2 equal to 0.71.

The aim of this work was to evaluate the cellular response to titanium nanotube arrays with variable crystalline structure. Cytotoxicity, viability and the ability of the titania nanotube arrays to stimulate adhesion and proliferation of adipose derived stem cells (ADSCs) was evaluated. Titania nanotube arrays were fabricated by electrochemical anodization of titanium in diethyleneglycol/hydrofluoric acid electrolyte at 60 V for 6 h, then annealed at 300, 530 and 630 °C for 5 h. The nanotube arrays were characterized using scanning electron microscopy (SEM), contact angle goniometry, x-ray diffraction (XRD) and protein adsorption. ADSCs were cultured on titania nanotube arrays at a density of 1 × 104 cells/ml. The cells were allowed to adhere and to proliferate for 1, 4 and 7 days. Cell viability was characterized by the CellTiter-Blue® Cell Viability Assay; and cell morphology was characterized by SEM. Cell adhesion, proliferation and morphology were characterized using fluorescence microscopy by staining the cells with DAPI and rhodamine/phalloidin. The results from this study showed that the annealing at 300 and 530 °C formed anatase phase, and annealing at 630 °C formed anatase/rutile phase. The results indicated that the modification of the crystalline structure (i.e. anatase/rutile phase) of titania nanotube arrays influenced the ADSC adhesion and proliferation. Future studies are now directed towards evaluating differentiation of this cellular model in osteoblasts.

This paper investigates the effect of initial tunnel construction on the future ground vibration levels generated during underground railway line operation. This is important because tunnel construction results in soil disturbance, thus inducing high soil strain levels near the tunnel lining. The resulting soil stiffness degradation impacts the future generation of ground-borne traffic vibration and it's propagation to the foundations of nearby buildings, however has never been investigated. Therefore, to address this, this work develops a novel hybrid modelling approach, consisting of a construction simulation model and an elastodynamics model. First the convergence-confinement method is used to determine the stress state induced during tunnel construction using a tunnel boring machine (TBM). Next a 2.5D FEM-PML model consisting of vehicle-track-tunnel-soil is used to predict the vibration fields induced by underground trains. To link the approaches, the soil stiffness degradation contours computed from the tunnelling simulation act as inputs for the 2.5D underground railway model. This facilitates the assessment of the effect of tunnel construction on vibration levels. It is found that railway ground-borne vibration levels are underestimated if construction effects are ignored, with discrepancies of up to 10 dB found at higher frequencies. Therefore, when estimating future vibration levels during the underground railway design stage (e.g. for subway, metro, high-speed lines … etc), tunnel construction should be considered as an operational source of uncertainty.

Resorbable materials are desirable components for applications such as temporary implants, as they degrade in a controlled manner until completion of the osseointegration of the bone, eliminating the need of a second surgery to remove them. Phosphate based glasses (PBG) have properties that allow them to be used as hard tissue substitutes with the advantage of being resorbable. Incorporation of strontium into PBG has been widely studied because it is considered a bone formation stimulator. Although strontium phosphate glasses have better cellular response, their degradation rate is higher. Some studies show that the addition of TiO 2 and MgO significantly reduces the degradation rate of soluble phosphate glasses. Furthermore, these oxides interfere with the chemical structure of the glass, and consequently improve their mechanical properties. Therefore, our aim was to evaluate the effect of dopants (TiO 2 and MgO) on a phosphate based glass and, consequently, on its degradation behavior, hardness, elastic modulus and fracture toughness. Our results showed that the glass structure was modified by the dopants, becoming more rigid, and as a result, decreasing the glass degradation, and increasing the hardness, elastic modulus, and fracture toughness.

espanolEl proceso sol-gel es un metodo interesante para la produccion de recubrimientos vitreos sobre sustratos vitroceramicos con el fin de mejorar su resistencia al rayado y al desgaste, y proporcionando ademas un aspecto homogeneo, vidriado y brillante que evite los costosos tratamientos finales de pulido. Este trabajo describe la preparacion de recubrimientos de silice y silice/circona por el metodo sol-gel sobre sustratos vitroceramicos del sistema Li2O-Al2O3-SiO2 (LAS) producidos por sinterizacion. Los recubrimientos se depositaron por la tecnica de inmersion y se caracterizaron mediante microscopia optica de luz reflejada y elipsometria espectral. Por otro lado, se determino la dureza y el modulo de elasticidad, ademas del coeficiente de friccion, la resistencia al desgaste y al rayado de los recubrimientos. Estos resultados se compararon con las propiedades del sustrato sin recubrir. Las capas depositadas confieren al sustrato un aspecto homogeneo, vidriado y brillante, mejorando el aspecto final y evitando el pulido. Sin embargo, estas capas no aumentan la resistencia al desgaste del sustrato, aunque igualan sus caracteristicas. EnglishThe sol-gel process is widely used to obtain coatings on glass-ceramic substrates in order to improve the scratch and abrasion resistance, also providing a bright and homogeneous appearance of a glaze avoiding expensive final polishing treatments. This paper describes the preparation of silica and silica / zirconia coatings by sol-gel method on Li2O-Al2O3-SiO2 (LAS) glass-ceramic substrates produced by sintering. The coatings were deposited by dip-coating on LAS substrates and characterized by optical microscopy and spectral ellipsometry. On the other hand, hardness and elastic modulus, coefficient of friction and abrasion and scratch resistance of the coatings were determined and compared with the substrate properties. Coatings deposited on LAS glass-ceramic confere the substrate a bright and homogeneous aspect, similar to a glaze, improving the appearance and avoiding the final polishing. However these coatings do not increase the scratch resistance of the substrate only equaling the properties of the glass-ceramic.

How should we forecast GDP? Should we forecast directly the overall GDP or aggregate the forecasts for each of its components using some level of disaggregation? The search for the answer continues to motivate several horse races between these two approaches. Nevertheless, independently of the results, institutions producing short-term forecasts usually opt for a bottom–up approach. This paper uses an application for the euro area to show that the option between direct and bottom–up approaches as the level of disaggregation chosen by forecasters is not determined by the results of those races.

In recent years, many surface modification processes have been developed in order to induce the osseointegration on titanium surface and thus to improve the implants' biocompatibility. In this work, Ti surface has been modified by shot blasting followed by anodic oxidation process in order to associate the good surface characteristics of both processes to obtain a rough and porous surface able to promote the titanium surface bioactivity. Commercially pure titanium (grade 2) plates were used on the surface treatments that were as follows: Shot blasting (SB) performed using alumina (Al2O3) particles, and anodic oxidation (AO) using NaOH electrolyte. The morphology, structural changes and the open-circuit potentials (OCP) of the surfaces were analyzed. It can be observed that an increase on the roughness of the blasted surface and a rough and porous surface happens after the AO process. The anodic film produced is thin and followed the blasted surface topography. It can be observed that there are small pores with regular shape covering the entire surface. X-ray diffraction results showed the presence of the anatase and rutile phases on the blasted and anodized surface after heat treatment at 600 °C/1 h. Concerning electrochemical measurements, when the different samples were submitted to open-circuit conditions in a physiological electrolyte, the protective effect increases with the oxidation process due to the oxide layer. When the surface was blasted, the OCP was more negative when compared with the Ti surface without surface treatments.

The evolution of the structure and properties of Cr/Cr oxide thin films deposited on HK40 steel substrates by reactive magnetron sputtering (RMS) was investigated and linked to their potential protective behavior against metal dusting. Deposition time, mode of oxygen feeding, and application of bias voltage were varied to assess their effect on the density, adhesion, and integrity of the films. All the films showed a very fine columnar microstructure and the presence of amorphous Cr oxide. Both, an increasing time and a constant oxygen flow during deposition led to the development of relatively low density films and mud-like cracking patterns. A graded oxygen flow resulted in films with fewer cracks, but a careful control of the oxygen flow is required to obtain films with a truly graded structure. The effect of the bias voltage was much more significant and beneficial. An increasing negative bias voltage resulted in the development of denser films with a transition to an almost crack-free structure and better adhesion. The amorphous oxide resulted in low values of hardness and Young's modulus.

Lithium disilicate glass has been submitted to a high pressure treatment associated to a heat treatment, and the effects of densification and crystallization at high pressure on the mechanical properties were evaluated. The hardness and elastic modulus were examined by instrumented indentation using a Berkovich tip. The crack pattern morphology after indentation with a cube corner indenter was also investigated. The hardness and elastic modulus of the samples submitted to high pressure at room temperature decreased with increasing pressure. The hardness and elastic modulus of the samples submitted simultaneously to high pressure (up to 7.7 GPa) and high temperature increased noticeably. The amount, length and type of cracks induced by the cube corner tip changed with increasing pressure. These results indicate that the high temperature treatment under high pressure improved the mechanical properties of LS 2 .

Guanabara Bay, a natural tropical embayment in Southeast Brazil adjacent to Rio de Janeiro, is important to the Brazilian economy as it provides areas for shipping, industry, recreation, and tourism. But commercial and residential urban development in the watershed results in water quality degradation. In Guanabara Bay, strong water quality gradients as a function of inputs and tidal flushing were evident. In the watershed, the urban and industrial areas degraded stream water quality, and the best water quality was in the upstream, rural areas. Steps have been initiated to collect or contain litter (ecoboats and ecobarriers) and reduce sewage discharge (sewage treatment plants). In spite of this, urban development continues to degrade Guanabara Bay ecosystem health. Large-scale international events hosted by Rio de Janeiro have brought widespread attention to Guanabara Bay pollution issues. Management actions have been identified to improve Guanabara Bay ecosystem health, including establishing a strong governance structure, restoring water quality in the rivers, bay and beaches, restoring habitats in Guanabara Bay and its watershed, and mitigating for climate change impacts. An ecosystem health report card was generated using monitoring data with stakeholder engagement for both Guanabara Bay and its watershed. The scientifically rigorous and transparent report card process can be used to track Guanabara Bay restoration progress.

AISI H13 die steel substrates were low pressure gas nitrided to different thicknesses and hardness values. Nitrided and non nitrided samples were subsequently coated with bi-layer TiAlN/TiN to two different thicknesses. The hardness was measured across the coating thickness and observed to be higher when a thinner coating was deposited over nitrided substrates. The hardness behavior across relatively thin (3 μm) coatings was not affected by the nitrided surface hardness or thickness of the nitride layer in the range of values examined here (80–150 μm). On the other hand, the hardness behavior of thicker coatings (8um) was affected by the nitrided layer, as the thicker coatings were soft due to their columnar structure. The specific wear rate of the duplex coatings was affected by the coating thickness and hardness distribution across the coating system.

Background Celiac artery (CA) occlusions/stenosis is infrequently associated with liver ischemia due to its unique vascularization, where portal vein provides about 75% of liver's perfusion. Collateral flow from gastroduodenal artery also provides, in most cases, enough blood supply to prevent ischemic hepatitis. In cases where these collateral pathways are compromised, severe liver ischemia can occur. Methods We present a case of acute mesenteric ischemia following gastric surgery that was treated with a hybrid retrograde CA stenting. Results We report a case of a 72-year-old male, who underwent gastric surgery for gastric cancer. On fourth postoperative day, he presented with acute abdomen, and on laparotomy, a partial duodenal suture dehiscence was found and suture closed. Owing to worsening of patient's clinical condition, with associated ischemic hepatitis, 2 days later, a computed tomography angiography was performed that showed a superior mesenteric artery (SMA) occlusion at its origin with an associated, severe, ostial stenosis of the CA. On laparotomy, irreversible visceral ischemia was found, which led to total colectomy, resection of 50 cms of small bowel, and splenectomy. Liver ischemia was also confirmed. Femoral access was used to try to cannulate the CA and cross its stenosis, without success. Taking advantage of the open abdomen, we then opted to place a 5F sheath in the splenic artery stump. From this retrograde approach, stenosis traversal was easy, and the CA was ballooned and stented with reperfusion of almost all the liver. Despite these efforts, patient died because of multiorganic failure, 8 days later. Conclusions Ischemic hepatitis is a rare but serious complication of CA/SMA occlusive disease. Its occurrence is at increased risk after surgeries, where collateral flow is compromised. The endovascular treatment is currently the preferred approach to treat visceral arteries occlusive disease; however, antegrade CA cannulation can be tricky, and in an open abdomen scenario, retrograde approach from the splenic artery can be an additional resource. This case demonstrates the flexibility of endovascular techniques and that they can provide useful solutions even during open surgery.

Introduction: Pleural effusions can complicate pneumonias in children and adolescents and are usually associated with a long hospital stay and increased morbidity. Aims: To characterise a population of patients with parapneumonic pleural effusion and to establish possible prognostic factors on admission based on clinical, imaging and analytical data. To correlate treatment options with the outcome. Methods: Case review of patients under 18 years old with parapneumonic pleural effusion, admitted between July 1997 â June 2004 (7 years). Results: 118 patients were included, 60% male, with mean age 7 years. The incidence of pleural effusion increased throughout the period of the study. The admissions occurred predominantly in autumn and winter. On admission 60% of patients had respiratory distress and 39% chest pain. In 40% loculations were found on admission and were associated with longer hospital stay, longer course of antibiotic therapy and more frequent need for surgery. Thoracentesis was performed in 72% of patients (mean pH pleural fluid 7.24). The aetiologic agent was identified in 17% of cases: Streptococcus pneumoniae (five), Staphylococcus aureus (four) and Streptococcus pyogenes (four). In our study, 52% of patients underwent pleural drainage and 18% surgery. Median length of hospital stay was 15 days with mean 16.4 days (2 â 51). Discussion: Factors associated with worse prognosis were respiratory distress, loculations, empyema, low pH in pleural fluid, glucose or proteins in pleural fluid, high lactic dehydrogenase level in pleural fluid and high serum C-reactive protein. Pleural drainage and/or surgery can shorten hospital stay and improve outcome. Conclusion: Complicated parapneumonic pleural effusions are managed successfully in centres with experience in the different types of procedure that might be necessary. Resumo: Introdução: Os derrames pleurais podem complicar as pneumonias na população pediátrica. Assumem especial importância pelas implicações na duração do internamento, geralmente prolongado, e pela morbilidade associada. Objectivos: Caracterizar uma população de doentes com pneumonia complicada de derrame; determinar os possíveis factores de prognóstico a partir de dados clínicos, radiológicos e analíticos na admissão; e avaliar a influência das intervenções terapêuticas na evolução da doença. Métodos: Revisão casuística dos doentes com idade inferior a 18 anos e derrame pleural parapneumónico, internados de Julho de 1997 a Junho de 2004 (7 anos). Resultados: Foram estudados 118 casos, 60% do sexo masculino, com idade média 7 anos. A incidência de derrame pleural aumentou ao longo do período do estudo. Verificou-se maior incidência de casos no Outono e no Inverno. Na admissão, 60% dos doentes apresentavam sinais de dificuldade respiratória e 39% dor torácica. Em 40% dos doentes foram detectados septos pleurais na admissão, o que se associou a maior duração de internamento e de antibioticoterapia e mais frequente necessidade de cirurgia. Em 72% dos doentes foi efectuada toracocentese (pH médio: 7,24). Em 17% foi possível isolar o agente: Streptococcus pneumoniae (cinco), Staphylococcus aureus (quatro) e Streptococcus pyogenes (quatro). Foram submetidos a drenagem pleural 52% e necessitaram de cirurgia 18%. A mediana da duração de internamento foi de 15 dias e a média de 16,4 dias (2 a 51). Discussão: Associam-se a pior prognóstico a presença de: sinais de dificuldade respiratória; septos; empiema; baixo valor no líquido pleural de pH, glicose ou proteínas; desidrogenase láctica elevada no líquido pleural e proteína C-reactiva sanguínea aumentada. A drenagem pleural e/ou cirurgia mais precoces provavelmente diminuem o tempo de doença e de internamento. Conclusão: Os derrames parapneumónicos complicados são tratados com êxito em centros de referência com experiência nos diferentes tipos de intervenção que poderão ser necessários. Key-words: Drainage, pleural effusion, pneumonia, prognosis, surgery, Palavras-chave: Pneumonia, derrame pleural, drenagem, cirurgia, prognóstico

This paper reports on a contact between Botucatu and Serra Geral Formations in Mato Grosso do Sul state (southwestern border of the Parana Basin), where this kind of sediment–lava interaction has never been described before. The palaeodune registers mean palaeocurrent towards southwest, and the main volcano-sedimentary features are preserved ripples, striations, chevron and crescentic marks, empty or sand-filled tubes and cooling cracks. These features indicate that when lava flows covered the dune, the Botucatu erg was active in the study area, hence consolidating the concept of the non-existence of a hiatus between the Botucatu and Serra Geral Formations.

During economic downturns, weak domestic demand developments seem to be an additional driver of exports, as firms increase their efforts to serve markets abroad to compensate the fall in domestic sales. This may constitute an additional mechanism adjustment for the euro area countries where real exchange rate variations are limited by the common currency itself and the present low inflation environment. However, this substitution effect between domestic and foreign sales could be different across euro area members. This paper uses panel data techniques to assess the role of the export structure in explaining these differences. Building a novel indicator for product concentration, the results suggest that domestic demand developments are more relevant to explain exports in countries with a lower product concentration index (that is, more diversified exports). This contributes to explain why euro area countries under stress registered different economic performance during the most recent years.