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This work studies the relative influence of the constructive characteristics of thermosiphon factory made solar heating systems of components such as absorber type, collector area, thermal insulation of both collector(s) and tank, tank volume and volume/area ratio, on the annual energy production, the annual efficiency and the solar fraction. The research has been conducted on 28 systems available in the market, tested according to Standard ISO 9459–5:2007 and simulated fo different European reference locations (Athens, Davos, Wurzburg and Stockholm) according to Standard EN 12976–2:2019. The results show that reduced volume has a marked influence on the energetic and efficiency behaviour of these systems. In particular, for reduced volume values greater than 0.8, the constructive characteristics have high influence on systems behaviour. On the contrary, for reduced volume values lower than 0.8, all tested systems have a similar behaviour at the same location. The results found in this study allow optimizing the design of TSWHS, as well as selecting a specific system according to the location and a daily load volume.

To evaluate individual and combined effect of captopril and telmisartan on systemic inflammation markers of hemodialysis (HD) patients. Randomized, double-blinded, controlled clinical trial. Patients on HD at least 2 months, with arteriovenous fistula, were randomly allocated to groups: (1) captopril/placebo (N 13); (2) telmisartan/placebo (N 13); (3) captopril + telmisartan (N 12); or (4) placebo/placebo (N 12). During 3 months, patients received oral drugs as follows: captopril 50 mg/day, telmisartan 80 mg/day or placebo. Patients excluded if they had conditions or were on drugs potentially influencing on inflammation. Clinical and biochemical evaluations were performed monthly. Serum tumor necrosis factor alpha (TNFα), interleukin 6 (IL-6), and C-reactive protein (CRP) were measured at 0, 1 and 3 months. Baseline, demographic, clinical and biochemical variables were comparable between groups. Baseline versus final inflammatory markers were: captopril/placebo TNFα, 2.47 (0.1–4.5) versus 1.73 (0.3–3.8) pg/ml; IL-6, 17.03 (7.2–23) versus 7.90 (0.7–19) pg/ml; CRP, 4.21 (1.6–18) versus 5.9 (3.0–28) mg/l; telmisartan/placebo TNFα, 3.03 (2.3–4.6) versus 1.70 (1.2–2.0) pg/ml; IL-6, 14.10 (5.5–23) versus 9.85 (6.2–13) pg/ml; CRP, 5.74 (2.1–13) versus 10.60 (1.5–27) mg/l; captopril + telmisartan TNFα, 1.43 (0.7–5.4) versus 0.40 (0.1–2.1) pg/ml; IL-6, 10.05 (4.9–23) versus 4.00 (0.7–7.7) pg/ml (p placebo/placebo TNFα, 3.13 (1.6–5.6) versus 1.64 (1.6–2.3) pg/ml; IL-6, 8.12 (5.4–16) versus 7.60 (2.4–15) pg/ml; CRP, 5.23 (1.9–16) versus 3.13 (1.5–18) mg/l. Monotherapy with captopril or telmisartan display a trend, but their combined treatment significantly decreased serum levels of IL-6. No remarkable changes on TNFα and CRP were observed.

While past studies on Airbnb pricing highlight the importance of room features, host characteristics and location factors, little has been investigated about whether these factors are the same across different property/room types, locations and seasons. To fill that gap, this paper presents a study about the drivers of Airbnb prices in Bristol using ordinary least squares (OLS) and geographically-weighted regression (GWR) methods. The estimated models exhibit sharply different levels of goodness-of-fit, suggesting that the prices of different room types might not be explained by the same set of price factors. The results also uncover statistically significant differences between the price determinants of apartments and house listings and reveal spatial patterns in the price effects. These findings have implications for price setting and the assessment of competition. Future studies should account for potential differences across property/room types, as well as to consider the spatial variability of the estimated coefficients.

Herein we report the synthesis of unsupported bimetallic CoMo and trimetallic CoNiMo sulfide catalysts prepared by thermal decomposition (ex situ activation) of carbon-containing precursors and varying the nickel concentration for the hydrodesulfurization (HDS) of dibenzothiophene. The catalysts prepared were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, inductively coupled plasma mass spectrometry and BET surface area measurements. The results from the characterization showed that the addition of an alkyl chained precursor results in non-porous catalysts with low surface area and high carbon content, which negatively affects the formation of crystalline phases such as molybdenum sulfide and their performance in the HDS reaction. Furthermore, the addition of nickel has a negative effect on the catalysts since it was observed that when it was added, the reaction rate values decreased and the catalyst with the highest catalytic activity turned out to be the CoMo catalyst. Although nickel catalysts generally have more affinity for hydrogenation reactions, unsupported trimetallic catalysts showed a preference for the direct desulfurization pathway.

Pay what you want (PWYW) is an increasingly popular sales strategy in which consumers voluntarily decide how much to pay for a product or service. PWYW has often been described as an exercise in the “empathy economy,” where consumers' payment choices might be seen as empowered expressions of their tastes and preferences, and sellers have a stronger incentive for empathizing with them. Beyond their economic interest, PWYW experiences also deserve significant attention in the social sciences given that they challenge several key assumptions of rational choice and neoclassical economic theory, as well as conventional consumer behavior and pricing theories. This paper analyzes three plays performed at the Beckett Theater in Barcelona using PWYW with very profitable outcomes. Our analysis shows that socio‐psychological factors, such as payments attributed to others and satisfaction with the play, are the best predictors of customer payments.

Lanthanum aluminate-lanthanum zirconate composite was synthesized by using coprecipitation and powders were dried by spray-drying. Pseudoboehmite was used as a precursor of lanthanum aluminate during the precipitation process. Highly crystalline phases were obtained. Lanthanum zirconate exhibits a pyrochlore structure at lower synthesis temperature (>1500°C). Due drying technique lanthanum aluminate particles appear surrounded by lanthanum zirconate. No other remaining phases were observed and the phase distribution in the composite was homogeneous.

Objective The objective of the study was to determine the trend of variables related to tuberculosis (TB) from the Integrated Tuberculosis Research Program (PII-TB) registry of the Spanish Society of Pulmonology and Thoracic Surgery (SEPAR), and to evaluate the PII-TB according to indicators related to its scientific objectives. Method Cross-sectional, population-based, multicenter study of new TB cases prospectively registered in the PII-TB between 2006 and 2016. The time trend of quantitative variables was calculated using a lineal regression model, and qualitative variables using the χy test for lineal trend. Results A total of 6,892 cases with an annual median of 531 were analyzed. Overall, a significant down-ward trend was observed in women, immigrants, prisoners, and patients initially treated with 3 drugs. Significant upward trends were observed in patients aged 40−50 and >50 years, first visit conducted by a specialist, hospitalization, diagnostic delay, disseminated disease and single extrapulmonary location, culture(+), drug susceptibility testing performed, drug resistance, directly observed treatment, prolonged treatment, and death from another cause. The scientific objectives of the PII-TB that showed a significant upward trend were publications, which reached a maximum of 8 in 2016 with a total impact factor of 49.664, numbers of projects initiated annually, presentations at conferences, and theses. Conclusions PII-TB provides relevant information on TB and its associated factors in Spain. A large team of researchers has been created; some scientific aspects of the registry were positive, while others could have been improved.

La trombosis asociada al cáncer (TAC) constituye una complicación frecuente en pacientes con esta enfermedad. Existen tres opciones para la tromboprofilaxis: los anticoagulantes orales directos (ACOD), las heparinas de bajo peso molecular (HBPM) y las anti-vitamina K (warfarina). Se realizó una revisión sistemática para comparar las tres alternativas de tratamiento sobre efectividad bajo criterios de no inferioridad. Adicionalmente se analizaron el empleo de los ACOD y las HBPM contra placebo para evidenciar superioridad. El evento primario fue la trombosis venosa profunda recurrente (TVPr) y para seguridad, la hemorragia mayor. Un total de 9353 pacientes fueron clasificados en cuatro categorías: ACOD vs warfarina (4 estudios), ACOD vs HBPM (3 estudios), HBPM vs warfarina (3 estudios) y ACOD o HBPM vs placebo (4 estudios). Los resultados mostraron una superioridad de los ACOD sobre la warfarina en TVPr, RR(IC95%) igual a 0,70 (0,58-0,87), p

Background Cuba is one of the Latin American countries with the highest rates of organ donation. Social and cultural differences among the population throughout the country may also affect attitudes toward donation. Knowledge of these characteristics would facilitate awareness of the population most reluctant to donate and transplant. Objective We sought to analyze the differences in attitudes toward organ donation among Cubans living in the main capitals of Cuba. Materials and Methods Study population. The study group was the Cuban population living in the cities of Cienfuegos (n=636), Havana (n=920), and Santiago de Cuba (n=455), extracted from the database of the International Collaborative Donor Project. Sample of the population. Participants were older than 15 years, and data were stratified by geographic area, age, and sex. Assessment instrument. We used a validated questionnaire of attitude toward organ donation for transplant (PCID-DTO-Rios), anonymously filled in and self-administered. Statistics. Student t test was applied together with the χ2 test, complemented by an analysis of the remainders. Results The favorable attitude among inhabitants in Cienfuegos was 71.2% (n=453), 68.3% (n=628) among those in Havana, and 69.5% (n=316) among those in Santiago de Cuba (P Conclusions The attitude toward organ donation among the population of the main cities of Cuba was favorable and similar in all of them. The psycho-social profile toward organ donation was similar in the 3 cities.

This paper discusses the development of a coating made of solid waste and residual biomass and its application as ecological solar absorber coating. This absorbent solar coating is made with a binder that consists of essential grapefruit rind oil and expanded polystyrene, both obtained from waste materials, as well as forest biomass soot (FBS) processed by mechanical grinding and used as a functional photothermal material. This mixture produces a paint that can be applied to metallic substrates to form a solar energy-absorbing surface. The characterization and evaluation is shown in three steps: (a) Characterization of the materials using XRD, SEM, TEM, XPS, Raman spectroscopy and IR; (b) coating evaluation using AFM, optical characterization to measure solar absorption, TG to determine the operating temperature and laser flash analysis to determine thermal conductivity; and (c) a testing with thermosolar technology to determine the thermal parameters of solar cookers. It has been identified that the pseudo-amorphous carbon in FBS has solar energy absorption capacity due to the sp2-sp3 bonds present in this kind of carbon, associated with the material’s graphitic domain. Also, results show that the coating can be used with thermosolar technologies operating above 250 °C with a solar absorption index above 96%, and it has thermally-efficient properties. In addition, the coating, it shows better results with solar cookers than other coatings used with this technology, increasing cooking power, so it can potentially be employed with various thermosolar technologies due to the replicability of its materials, its low environmental impact and low economic cost.

Objectives This study sought to describe, in detail, the angiographic, gross macroscopy, and histological dissection of the conduction axis in humans. Background The recent upsurge of interest in specific pacing of the atrioventricular conduction axis has emphasized the need for precise knowledge of the location of the atrial and penetrating components of the atrioventricular conduction axis. Methods A total of 41 human hearts were studied by serial histological sectioning and an additional 3 hearts by gross dissection. One of the hearts studied histologically was also dissected to show the location of the conduction axis prior to serial sectioning. The anatomical findings were then compared with the results of angiography undertaken in the catheter laboratory in 60 patients undergoing electrophysiological studies. Results Marked variation of the location of the transition from atrioventricular conduction axis to the penetrating atrioventricular bundle, or the bundle of His, relative to the landmarks of the triangle of Koch was observed. In just over one-half of both the specimens and the patients, the site of penetration was on the atrial aspect of the hinge of the septal leaflet of the tricuspid valve, with further variation noted relative to the apex of the triangle of Koch. Based on measurements of the histological sections, marked variation in the dimensions of the axis and its adjacency to the right-sided endocardium were also found. In almost three-fifths of hearts, an interventricular component of the fibrous membranous septum was not able to be identified. The significance of these findings to those who seek to perform selective pacing of the atrioventricular conduction axis are discussed. Conclusions Marked variability of the location of the conduction axis within the triangle of Koch is reported. In three-fifths of hearts, the interventricular component of the fibrous membranous septum is nonexistent.

Introduction The attitude toward living liver donation (LLD) among the Spanish population is mostly positive; however, the reality is that liver transplants from live donations are currently minimal. Given this situation, studies that analyze these discrepancies should be carried out. Objective Analyze the attitude toward LLD among family members of patients on the waiting list for liver transplantation. Method Population under study. First-degree relatives of the patients included in the waiting list for liver transplantation. Inclusion criteria. 1. Have the patient's authorization for family members to participate; 2. Accept, the relative, to participate in this investigation; and 3. Be over 18 years old. Opinion survey. The attitude toward LLD is assessed through a questionnaire on psychosocial aspects. Results Patients who accepted family members’ participation in the study were 21 of 112, of which 9 placed restrictions on family access, and 12 authorized family members without restrictions. The participants were 1. children: 52.2% (n = 24); 2. brothers: 30.5% (n = 14); and 3. partners: 17.3% (n = 14). Finally, the authorized relatives and participants in the study were 45. Of these, only 44% (n = 20) would accept to be donors. Conclusions The access to the LLD of the relatives starts from the restriction and initial rejection of the patients themselves on the waiting list. The promotion of LDD is to initially sensitize patients.

Puerto Ricans are one of the majority immigration groups in Florida. However, little is known about their attitudes toward xenotransplantation (XenoTx), a still experimental technique, which is making significant progress.To analyze the attitude toward XenoTx of organs among the population of Puerto Rican residents in Florida.Population under study. Sample taken from the International Collaborative Donor Project and formed by the population born in Puerto Rico and resident in Florida.Over 15 years stratified by age and sex. Instrument valuation. Validated questionnaire of attitude toward xenotransplantation "PCID-XenoTx-Ríos." Setting for the study. Random selection of people to survey based on stratification. Immigrant assistance associations in Florida were consulted to locate potential respondents.Of the 259 respondents, 16% are in favor of XenoTx if the results are similar to those obtained with human organs, 74% are against, and 10% are doubtful. If the results are worse than with human organs, only 2% are in favor, 74% against, and 24% undecided. The variables that are associated with this attitude are the following: sex (P = .001); marital status (P .001); have offspring (P = .004); level of education (P .001), opinion of a partner toward donation (P = .008), religious beliefs (P .001), knowing the opinion toward donation of religion (P .001), prosocial activity (P .001), attitude toward donation (P ≤ .001), previous relationship with donation (P .001), possibility of receiving a transplant in the future (P = .001), and attitude toward donation to a relative (P .001).The Puerto Rican population residing in Florida does not hold a favorable attitude toward xenotransplantation.

Nejayote is a highly polluting wastewater discarded after the nixtamalization process of maize (Zea mays L.). It contains many organic compounds and unused nutrients. In this study, we optimized the biological treatment of nejayote through Bacillus clausii-induced fermentation, using the response surface methodology, to enhance the content of bioactive compounds, antioxidant and antimicrobial activities of nejayote. The optimal fermentation temperature and time were 36 °C and 4.8 days, respectively, which produced a biomass of 9.1 log10 CFU mL−1 of B. clausii, total phenolic content of 524 mg equivalents of gallic acid per 100 mL sample, and antioxidant activity of 2876 µmol equivalent of trolox per 100 mL sample. The fermentation significantly increased the total phenolic content (~ 150%) and antioxidant activity (~ 30%), increased the content of 8-O-4-hydrodiferulic, 8-O-4-hydrotriferulic, and ferulic acids, and synthesized caffeic acid when compared with non-fermented nejayote. The fermentation process improved the antimicrobial activity of nejayote against Salmonella Typhimurium (3.5-fold) and Enterococcus faecalis (2.72-fold) after 12 h as compared to non-fermented nejayote. B. clausii-fermented nejayote obtained by this alternative eco-friendly process is thus a product with increased bioactive properties that could be used as functional ingredient in different food products.

In this work, multiple-wall carbon nanotubes (MWCNTs) were purified with an acid treatment and subsequently dispersed using commercial surfactants, such as amino trimethyl phosphonic acid and nonyl...

Category five hurricanes Irma and Maria (September 2017) caused significant damage to shallow seagrass communities across Puerto Rico. The magnitude and spatial extent of hurricane impacts on representative seagrass habitats of Culebra Island were addressed using a combination of random photo-quadrats and before–after hurricanes GIS-based imagery analyses. There was a significant loss of shallow seagrasses across all nine surveyed locations. Most of the documented impacts were associated with sediment bedload (horizontal transport), which resulted in burial and suffocation. There was also localized physical disruption of the seagrass habitat matrix across locations exposed to stronger wave action, creating major scars and exposing below-ground structure to further disintegration by future storm events. Displaced coral rubble also caused seagrass burial. Aerial imagery analyses (2007, 2010, 2017) showed a significant decline in seagrass percent cover. Seagrass decline was positively correlated with wave exposure (p

In this work, the Al-10Mg nanostructured alloy was synthesized by high-energy mechanical milling. Subsequently, the powders consolidated under a uniaxial pressing in the air. The as milled powders were analyzed using scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and differential scanning calorimetry (DSC). SEM and XRD also characterized the sintered samples. Vickers microhardness of sintered Al-10Mg alloy was measured. SEM, XRD, and TEM characterizations show that the Al-10Mg alloy was synthesized after 10 h milling. The X-ray powder analysis of the structural parameters showed the increment with the time of the lattice parameter, strain as well as the solubility of Mg in Al. Besides, XRD and TEM studies showed that the crystallite size was reaching an average value of 19 nm after 10 h milling. XRD patterns of the all sintered specimens show the formation of the MgAl2O4 spinel phase. After powders compaction, the specimen sintered at 420?C for 2 h shows microhardness of 125 HV.

The aim of this paper is to present a new bidirectional DC-DC linearized converter model for use in power demand and recovery units mainly used in Lightweight Electric Vehicle applications. The model significantly reduces the simulation time of the experiments performed, with up to a 4450-fold decrease in simulation times with respect to the original switched DC-DC topology. The study begins with a literature review of available switched converters, after which the presented topology is selected. The object-oriented modeling language Modelica® is used to implement the converter in the Dymola® modeling environment. Components and base classes from the Modelica Standard Library and VehicleInterfaces library are mainly used for better interoperability. Because of the intensive use of converters in the whole vehicle and the time consumed by the converter simulations due to high frequency commutation, a linearized DC-DC converter model is proposed. Comparison tests are performed between the reference switched models and the proposed linearized models in Dymola® tool to validate the linearized model behaviour. Nearly identical responses are obtained for both models, while simulation times are reduced as much as 1/4450 for the linearized converter. Furthermore, validation tests are carried out between the proposed linearized model in Dymola® and a reference switched model in LTspice® specific purpose simulation package for switched electronic circuits. Excellent agreement in the responses of both models is observed.

The articles in this special section focus on data driven optimization for transportation and smart mobility applications. We live in an era of major societal and technological changes. Transportation de-carbonization and postindustrial demographic trends, such as massive migrations and an aging society, generate new challenges for cities, making the efficient and sustainable management of services and resources more necessary than ever. Cities must evolve, transform, and become smart to cope with these realities. According to the literature, a city can be referred to as smart when investments in human and social capital and traditional (transportation) and modern [information and communications technology (ICT)] communication infrastructure fuel sustainable economic growth and high quality of life, with a wise management of natural resources, through participatory government.

Plasmonic and magnetic silicon hybrids are suitable hyperthermia nanoagents owing to their ability to generate heat under an external stimulus in addition to their biocompatibility, limited aggregation, dielectric properties, and surface functionalization. In this chapter, a discussion will be provided the applications of plasmonic and magnetic silicon hybrid nanoparticles in hyperthermia treatments. We shall first introduce the fundamentals of nanoparticle heating with the mechanisms triggered by localized surface plasmon polaritons and alternating magnetic fields. The synthesis and characterization of plasmonic and magnetic silicon hybrid nanoparticles will then be described, including examples of promising hyperthermia nanoagents designed to possess a heating efficient conversion. The last topic deals with hyperthermia in vivo and in vitro applications for pathological diseases, especially those related to malignant tumor cells and bacterial infections.

Antimicrobial resistance bacteria are nowadays ubiquitous. Its presence has been reported in almost every type of source, from water for agricultural and recreative use, water distribution pipes, and wastewater, to food, fomites, and clinical samples. Enterobacteriaceae, especially Escherichia coli, are not the exception, showing an increased resistance to several antibiotics, causing a global health and economic burden. Therefore, the monitoring of fecal microbiota is important because it is present in numerous reservoirs where gene transfer between commensal and virulent bacteria can take place, representing a potential source of resistant E. coli. In this work, antibiotic resistance profiles of 150 E. coli isolates from environmental, animal, and human samples, collected in three rural areas in Panama, were analyzed. A total of 116 isolates were resistant to at least one of the nine antibiotics tested. Remarkably, almost 100% of these exhibited resistance to tetracycline. Plasmid-associated tetA and tetB genes were detected in 42.86% of the isolates analyzed, tetA being the most prevalent. These results suggest that tetracycline resistance would be used as a convenient indicator of genetic horizontal transfer within a community.

To the best of our knowledge, "sweet mini bell" peppers have not been extensively investigated. In this study, we evaluated the bioaccessible phenolic compounds released during intestinal digestion and identified and quantified the microbial metabolites derived from phenolic compounds bioconversion during the in vitro colonic fermentation. A total of 66 phenolic compounds were determined. The results obtained in this study indicate that hydroxycinnamic acids (22 to 32 mg/100 g dw) and flavonoids (99 to 102 mg/100 g dw) headed by quercetin, luteolin and kaempferol glycosidic derivatives were the main bioaccessible phenolic compounds during in vitro intestinal digestion of mini bell peppers. The yellow variety contained the highest concentration of bioaccessible flavonoids (80 mg/100 g dw). For the first time in mini bell peppers, dihydroferulic acid was detected, in the three varieties studied. 3-(4-hydroxyphenyl)propionic acid was the major metabolite found after 12-24 h fermentation of all samples (44 to 102 µM/L). Further cell culture or in vivo studies are needed to elucidate the biological activities of the phenolic compounds identified in mini bell peppers.

We present the magnetic, structural and 57Fe Mossbauer characterization of soils collected from an ancient mercury contaminated city named Huancavelica in Peru. The characterization results indicate that silicates and carbonates are the main mineralogical constituents in the samples. In addition, 57Fe Mössbauer spectra at room temperature reveal, the presence of two components: a magnetic component related to magnetic Fe-oxides (magnetite, hematite, goethite) and a high non-magnetic component related to Fe+3 in high spin configuration and tetrahedral coordination in silicates. The magnetization measurements present screening of paramagnetic, ferromagnetic and antiferromagnetic signals, typical from soils containing different silicates and iron minerals. Remarkably the Verwey and Morin transitions corresponding to magnetite and hematite, respectively, are screened by the paramagnetic signal corresponding to the major silicate components in the samples. Overall, the soils are mainly composed of crystalline and amorphous silicates, calcites and iron bearing which are typical from Andean soils.

The increasing use of thermoluminescence (TL) materials as radiation detectors with application in different areas of ionizing radiation has motivated research on new materials with adequate luminescent characteristics. In this work, experimental results gadolinium aluminate (GdAlO

Products and outputs for water quality monitoring are made available in the IM4ManilaBay MapABLE Web Portal, a web-based GIS platform that serves as a repository of processed maps for Manila Bay and linked systems. The Portal is also linked with the MASDAN mobile application that has been developed to allow the public to report different environmental issues. The web development involved the utilization of geospatial content management system, spatial database system, operating systems, programming, and style language. Services included frontend and backend development. The Web Portal serves as a repository for all outputs derived for water quality monitoring. It contains processed results, technical overview on the developed models and tools, historical data viewing and use of basic geoprocessing tools, and viewing of reported incidents from the MASDAN app. It is expected that the Web Portal will contribute significantly in the efforts of communities and environmental agencies to implement policies for sustainable development and management of Manila Bay and its watershed.

Nanostructured (Fe0.5Ni0.5)92Zr5B3 alloy was prepared by milling a blend of pre-alloyed Fe50Ni50 precursor and high purity chemical elemental powders of Zr and B in a high-energy ball mill setup. Rietveld refinement of the X-ray diffraction pattern of the final sample (30 h of milling) revealed presence of two Fe–Ni rich phases [disordered fcc γ–(Fe,Ni) alloy with Zr and B and the atomically ordered FeNi] with grain sizes in nanometer scale. Fe and Ni atoms were locally probed using extended X-ray absorption fine structure EXAFS and 57Fe Mossbauer spectroscopy. Whilst EXAFS analysis of milled samples suggested structural properties similar to the pre-alloyed precursor, Mossbauer data have shown the Fe2B phase formation after 3 h of milling, suggesting that the final material consists of nanograins of ordered FeNi (8%) and Fe2B (6%) phases dispersed in solid solution of γ–(Fe,Ni) alloy rich in nickel (86%) with Zr and B atoms impregnated in grain boundary defects.