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Cryptococcosis, caused by Cryptococcus gattii sensu lato, is an emerging disease that was initially found in (sub)tropical regions but recently expanded to temperate regions. Cryptococcus gattii s.l. infections are mostly encountered in healthy individuals, frequently affecting both lungs and the central nervous system (CNS). Usually, C. gattii s.l. is less susceptible to antifungal compounds than its counterpart, C. neoformans s.l. We studied 18 clinical C. gattii s.l. isolates with amplified fragment length polymorphism (AFLP) fingerprinting, mating-typing, multi-locus sequence typing (MLST) and antifungal susceptibility testing. All isolates were C. deuterogattii (genotype AFLP6/VGII), 14 were mating-type α and four were type a. Amphotericin B, itraconazole, voriconazole, posaconazole and isavuconazole showed high activity, with minimum inhibitory concentration (MIC) ranges of 0.063-0.25, 0.031-0.25, 0.031-0.25, 0.031-0.25 and <0.016-0.25 µg mL-1, respectively. Fluconazole and flucytosine had high geometric mean MICs of 2.07 and 3.7 µg mL-1, respectively. Most cases occurred in immunocompetent patients (n = 10; 55.6 %) and CNS involvement was the most common clinical presentation (n = 14; 77.8 %). Three patients (16.7 %) showed sequelae, hyperreflexia, dysarthria, diadochokinesia, anosmia and upper limb weakness. In conclusion, all infections were caused by C. deuterogattii (AFLP6/VGII) and the majority of patients were immunocompetent, with the CNS as the most affected site. All antifungal drugs had high in vitro activity against C. deuterogattii isolates, except fluconazole and flucytosine.
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Antifúngicos/farmacología , Criptococosis/microbiología , Cryptococcus gattii/clasificación , Cryptococcus gattii/efectos de los fármacos , Farmacorresistencia Fúngica , Análisis del Polimorfismo de Longitud de Fragmentos Amplificados , Brasil/epidemiología , Criptococosis/epidemiología , Cryptococcus gattii/genética , Cryptococcus gattii/aislamiento & purificación , Dermatoglifia del ADN , Femenino , Genes del Tipo Sexual de los Hongos , Genotipo , Humanos , Masculino , Pruebas de Sensibilidad Microbiana , Tipificación de Secuencias MultilocusRESUMEN
This paper describes the diversity of rodent fauna in an area endemic for hantavirus cardiopulmonary syndrome (HCPS) in Brazil, the population dynamics and the relationship of rodents with hantavirus in the Cerrado (savanna-like) biome. Additionally, an analysis is made of the partial S segment sequences of the hantaviruses obtained from serologically confirmed human HCPS cases and from rodent specimens. Rodents were collected during four campaigns. Human serum samples were collected from suspected cases of HCPS at hospitals in the state of Minas Gerais. The samples antibody-reactive by ELISA were processed by RT-PCR. The PCR product was amplified and sequenced. Hantavirus was detected only in Necromys lasiurus, the wild rodent species most prevalent in the Cerrado biome (min-max: 50-83·7%). All the six human serum samples were hantavirus seropositive and five showed amplified PCR products. The analysis of the nucleotide sequences showed the circulation of a single genotype, the Araraquara hantavirus. The environmental changes that have occurred in the Cerrado biome in recent decades have favoured N. lasiurus in interspecific competition of habitats, thus increasing the risk of contact between humans and rodent species infected with hantavirus. Our data corroborate the definition of N. lasiurus as the main hantavirus reservoir in the Cerrado biome.
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Reservorios de Enfermedades/veterinaria , Síndrome Pulmonar por Hantavirus/veterinaria , Orthohantavirus/fisiología , Enfermedades de los Roedores/epidemiología , Roedores , Adulto , Animales , Brasil/epidemiología , Femenino , Genotipo , Pradera , Orthohantavirus/genética , Síndrome Pulmonar por Hantavirus/epidemiología , Síndrome Pulmonar por Hantavirus/virología , Humanos , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Filogenia , Dinámica Poblacional , Prevalencia , Enfermedades de los Roedores/virología , Roedores/fisiología , Análisis de Secuencia de ADN , Estudios Seroepidemiológicos , Proteínas Virales/genética , Proteínas Virales/metabolismo , Adulto JovenRESUMEN
Rickettsia rickettsii infection is being increasingly recognized as an important cause of fatal acute illness in Brazil, where this tick-borne disease is designated Brazilian spotted fever (BSF). In this study we report five fatal cases of BSF in employees of an animal shelter in an urban area in the municipality of Rio de Janeiro in southeast Brazil after a natural disaster on 11 January 2011. Four of the cases occurred from 27 January to 11 April 2011, while the fifth fatal case was identified in April 2012. Three cases were confirmed by molecular analysis and two by epidemiological linkage. An investigation of BSF was performed in the animal shelter, and blood samples were collected from 115 employees and 117 randomly selected dogs. The presence of high levels (1024-4096) of antibodies against spotted fever group rickettsiae was found in three (2·6%) employees and 114 (97·5%) dogs. These findings emphasize the need to consider BSF as a possible cause of undifferentiated febrile illness, especially dengue and leptospirosis, in patients occupationally exposed to dogs heavily infested by ticks, mainly working at kennels and animal shelters that have inadequate space for the animals housed and frequently providing an environment conducive to exposure to pathogens such as R. rickettsii.
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Anticuerpos Antibacterianos/inmunología , Enfermedades de los Perros/diagnóstico , Vivienda para Animales , Enfermedades Profesionales/diagnóstico , Rickettsia rickettsii/inmunología , Fiebre Maculosa de las Montañas Rocosas/veterinaria , Garrapatas , Adulto , Animales , Brasil , Dengue/diagnóstico , Diagnóstico Diferencial , Perros , Resultado Fatal , Femenino , Humanos , Leptospirosis/diagnóstico , Masculino , Persona de Mediana Edad , Enfermedades Profesionales/inmunología , Fiebre Maculosa de las Montañas Rocosas/diagnóstico , Fiebre Maculosa de las Montañas Rocosas/inmunología , Población UrbanaRESUMEN
Total mercury concentrations were determined by atomic absorption spectrometry in muscle tissue of two commercially important species of carnivorous fishes croaker (Micropogonias furnieri) and cutlassfish (Trichiurus lepturus) caught in Itaipu estuary, Rio de Janeiro. In this study, whitemouth croaker presented more mercury than Atlantic cutlassfish. Bioaccumulation differences can be explained by the biological behavior of juveniles whitemouth croaker, that remain in the estuary up to maturity, which makes them good indicators of local environmental impacts (0.110 mg Kg(-1) HgT). It also can be explained by differences in nutritional requirements between the different life stages of two species. The analysis showed the presence of low levels of the metal. However, our results suggest a possible risk to human health, depending on the level of fish consumption.
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Monitoreo del Ambiente/métodos , Peces/metabolismo , Mercurio/análisis , Músculos/química , Contaminantes Químicos del Agua/análisis , Animales , Conducta Animal/efectos de los fármacos , Brasil , Peces/crecimiento & desarrollo , Cadena Alimentaria , Humanos , Mercurio/farmacocinética , Perciformes/metabolismo , Contaminantes Químicos del Agua/farmacocinéticaRESUMEN
This study investigates the scope of application of a recently designed inversion methodology that is capable of obtaining structural information about disordered systems through the analysis of their conductivity response signals. Here we demonstrate that inversion tools of this type are capable of sensing the presence of disorderly distributed defects and impurities even in the case where the scattering properties of the device are only weakly affected. This is done by inverting the DC conductivity response of monolayered MoS2films containing a minute amount of AuCl3coordinated complexes. Remarkably, we have successfully extracted detailed information about the concentration of AuCl3by decoding its signatures on the transport features of simulated devices. In addition to the case of theoretically generated Hamiltonians, we have also carried out a full inversion procedure from experimentally measured signals of similar structures. Based on experimental input signals of MoS2with naturally occurring vacancies, we were able to quantify the vacancy concentration contained in the samples, which indicates that the inversion methodology has experimental applicability as long as the input signal is able to resolve the characteristic contributions of the type of disorder in question. Being able to handle more complex, realistic scenarios unlocks the method's applicability for designing and engineering even more elaborate materials.
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Rapid reaction time, high attainable temperatures, minimum operating voltage, excellent optical transmittance, and tunable sheet resistance are all desirable properties of transparent conductors, which are important thin-film components in numerous electronic devices. A seamless nanowire network (NWN) refers to a structure composed of nanowires that lack interwire contact junctions, resulting in a continuous and uninterrupted network arrangement. This seamless nature leads to unique properties, including high conductivity and surface area-to-volume ratios, which make it a promising candidate for a vast application range in nanotechnology. Here, we have conducted an in-depth computational investigation to study the thermo-electro-optical properties of seamless nanowire networks and understand their geometrical features using in-house computational implementations and a coupled electrothermal model built in COMSOL Multiphysics software. Sheet resistance calculations were performed using Ohm's law combined with Kirchhoff circuit laws for a random resistor network and compared with those obtained employing COMSOL. In this work, aluminium, gold, copper, and silver nanowires are the materials of choice for testing the transparent conduction performance of our systems. We have studied a wide range of tuning parameters, including the network area fraction, the width-to-depth aspect ratio, and the length of the nanowire segments. We obtained corresponding figures of merit (optical transmittance versus sheet resistance) and temperature distributions to provide a complete characterization of the performance of real-world transparent conductors idealized with seamless NWNs. Our analysis accounted for the thermo-electro-optical responses of the NWNs and the inspection of various controlling parameters depending on system design considerations to shed light on how the electrical transport, optical qualities, and thermal management of these systems can be optimized.
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Nanocables , Nanocables/química , Plata/química , Nanotecnología , Cobre/química , ElectrónicaRESUMEN
This research aimed to evaluate the influence of high-intensity ultrasound (HIU) levels (control: 0; high: 747.79; ultra-high: 1344.17 Wcm-2) on pH, instrumental color (redness, R630/580, hue angle and chroma) and oxidative stability (lipid and protein oxidation) of Psoas major (PM) muscle from Nellore cattle raised in two feeding systems: grain and pasture. Using a structural equation modeling (SEM) approach, the relations (P > 0.05) between exogenous (HIU levels) and endogenous (pH, color, lipid and protein oxidation) variables were observed. In beef from grain-fed animals the pH was directly and negatively related to lipid oxidation (γ = -0.321), hue angle (γ = -0.847) and chroma (γ = -0.442) and protein oxidation (γ = -0.752). In PM from pasture-fed HIU exhibited a negative relation with lipid (γ = -0.144) and protein (γ = -0.743) oxidation, suggesting a possible positive influence on the oxidative stability of meat and a positive relation with redness (γ = 0.197) and R630/580 (γ = 0.379). The HIU positively influenced the color and oxidative stability of beef from Bos indicus cattle, and a synergistic effect of HIU and feeding system on beef from pasture-fed animals.
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Schistosomiasis, caused by Schistosoma mansoni Sambon, 1907, is a severe and widely distributed parasitic disease, affecting about 200 million people worldwide. The disease is recognized by elevated mortality rates, especially among those living in areas of poor sanitation. Currently, the chemotherapeutic treatment is solely based on using the praziquantel drug. Therefore, there is a need for the discovery of new medicines for the treatment of this parasitosis. Thus, this work aimed to evaluate the schistosomicidal activity of ethanolic crude extracts from the branches, leaves, flowers, and fruits of Handroanthus impetiginosus (Mart ex DC.) Masttos and characterize its metabolic profile by UPLC-ESI-QTOF analysis. Evaluation of plant extract on S. mansoni was carried out in adult worms in vitro, in which the mortality rate was quantified, and the damages in the tegument of the worms were monitored. All extracts induced changes in the viability of adult males of S. mansoni, causing the death of the parasites, which was directly dependent of the concentration.
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Bignoniaceae , Esquistosomicidas , Tabebuia , Humanos , Masculino , Esquistosomicidas/farmacología , Esquistosomicidas/uso terapéutico , Frutas , Etanol , Flores , Extractos Vegetales/farmacología , Extractos Vegetales/uso terapéuticoRESUMEN
A suspended multicore fiber sensor for simultaneous measurement of curvature and strain is proposed. The spectral response shows evidences of several interferences arising from the seven cores of the fiber. Once the sensing head presents different sensitivities for curvature and strain measurements, these physical parameters can be discriminated by using the matrix method. The rms deviations are ±19 m(-1) and ±12.90 µÎµ for curvature and strain measurements, respectively.
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A highly birefringent photonic bandgap Bragg fiber loop mirror configuration for simultaneous measurement of strain and temperature is proposed. The group birefringence and the sharp loss peaks are observable in the spectral response. Because the sensing head presents different sensitivities for strain and temperature measurands, these physical parameters can be discriminated by using the matrix method. It should be noted that this Bragg fiber presents high sensitivity to temperature, of â¼5.75 nm/°C, due to the group birefringence variation. The rms deviations obtained are ±19.32 µÎµ and ±0.5 °C, for strain and temperature measurements, respectively.
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OBJECTIVE: To evaluate the frequency and clinical features of endemic and other opportunistic infections in liver or kidney transplant recipients in four transplant centres in different geographical areas of Brazil. METHODS: Retrospective analysis of medical and laboratory records of four transplant centres on endemic and other opportunistic infections in liver or kidney transplant recipients. Analyses were performed with spss statistical software. RESULTS: From 2001 to 2006, 1046 kidney and 708 liver transplants were registered in all centres. The average age was 42 years. Among 82 (4.7%) cases with infections, the most frequent was tuberculosis (2.0%), followed by systemic protozoal infections (0.7%), toxoplasmosis (0.4%) and visceral leishmaniasis (0.3%). Systemic fungal infections occurred in 0.6%, of which 0.4% were cryptococcosis and 0.2% were histoplasmosis. Dengue was the only systemic viral infection and was registered in two cases (0.1%), of which one was classified as the classic form and the other as dengue haemorrhagic fever. Nocardiosis was described in one case (0.05%). The infectious agents most frequently associated with diarrhoea were Blastocystis sp., Schistosoma mansoni and Strongyloides stercoralis. CONCLUSIONS: Opportunistic Infections in transplant patients have a wide spectrum and may vary from asymptomatic to severe infections with high mortality. A better understanding of the epidemiology of endemic pathogens and clinical manifestations can contribute to the establishment of an early diagnosis as well as correct treatment aimed at decreasing morbidity and mortality.
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Enfermedades Endémicas/estadística & datos numéricos , Huésped Inmunocomprometido , Trasplante de Riñón/efectos adversos , Trasplante de Hígado/efectos adversos , Infecciones Oportunistas/epidemiología , Trasplante de Órganos/efectos adversos , Adulto , Brasil/epidemiología , Enfermedades Endémicas/prevención & control , Femenino , Humanos , Inmunosupresores/uso terapéutico , Trasplante de Riñón/mortalidad , Trasplante de Hígado/mortalidad , Masculino , Trasplante de Órganos/mortalidad , Complicaciones Posoperatorias/epidemiología , Estudios RetrospectivosRESUMEN
Obtaining conductance spectra for a concentration of disordered impurities distributed over a nanoscale device with sensing capabilities is a well-defined problem. However, to do this inversely, i.e., extracting information about the scatters from the conductance spectrum alone, is not an easy task. In the presence of impurities, even advanced techniques of inversion can become particularly challenging. This article extends the applicability of a methodology we proposed capable of extracting composition information about a nanoscale sensing device using the conductance spectrum. The inversion tool decodes the conductance spectrum to yield the concentration and nature of the disorders responsible for conductance fluctuations in the spectra. We present the method for simple one-dimensional systems like an electron gas with randomly distributed delta functions and a linear chain of atoms. We prove the generality and robustness of the method using materials with complex electronic structures like hexagonal boron nitride, graphene nanoribbons, and carbon nanotubes. We also go on to probe distribution of disorders on the sublattice structure of the materials using the proposed inversion tool.
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The tambaqui (Colossoma macropomum) is a fish of primary importance in South American aquaculture, principally in the Amazon region and has a particularly unique diet in the wild. Oryza spp, or Wild rice as it is commonly known, is native to the floodplains of muddy rivers in the Amazon region. The aim of this study was to analyze the physical performance and the effects of dietary levels of Oryza spp. via the hematological parameters, total food intake, conversion efficiency, growth ratio and swimming performance of this fish. Diets containing 45% Oryza spp. induced the best performance in tambaqui. Diets containing 15% and 30% did not affect these indices, thus indicating that this amount of Oryza can be used as an alternative energy source for this important species within Brazilian aquaculture.
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Characiformes , Oryza , Animales , Acuicultura , Brasil , RíosRESUMEN
A 4-year (2005-2008) norovirus (NoV) surveillance study was conducted in the state of Rio Janeiro, Brazil, to demonstrate the role of these viruses in outbreaks and sporadic cases of acute gastroenteritis. A cohort of 1,687 fecal samples was obtained from patients with gastroenteritis; 324 were rotavirus-positive. Of the remainder 1,363 rotavirus-negative samples, 1,087 samples were tested for NoV RNA in this study. The study enrolled 267 outpatients from Municipal Public Health Centers and 820 inpatients, whose samples were obtained by active surveillance in Public Hospitals. Fecal samples were tested by reverse transcription (RT) followed by polymerase chain reaction (PCR) using the MON 431-434 set of degenerate primers for NoV GI and GII detection, and there were 35.1% (381/1,087) positive samples for NoV, consisting of 30.2% (248/820) and 49.8% (133/267) from inpatient and outpatient, respectively. Children infected by NoV had significantly more frequent mucus in feces, vomiting and fever. No seasonal pattern in NoV infections was observed in patients admitted to hospital; however, two peaks of NoV infections were observed from ambulatory cases, suggesting that there was an occurrence of outbreaks in those time periods. Molecular characterization revealed GII to be the most prevalent genogroup, totaling 96.3% (104/108) of all sequences analyzed, and GII.4 was the genotype detected most frequently (80.7%), followed by GII.6, 3, 14, 7, and 8. Two GI strains, GI.2 and GI.3, were also observed. The number of outbreaks and sporadic cases described in this study highlights the need to implement diagnosis of NoV in surveillance laboratories.
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Infecciones por Caliciviridae/epidemiología , Gastroenteritis/epidemiología , Norovirus/aislamiento & purificación , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Brasil/epidemiología , Infecciones por Caliciviridae/patología , Infecciones por Caliciviridae/virología , Niño , Preescolar , Cartilla de ADN/genética , Brotes de Enfermedades , Heces/virología , Femenino , Gastroenteritis/patología , Gastroenteritis/virología , Genotipo , Humanos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Norovirus/clasificación , Norovirus/genética , ARN Viral/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Rotavirus/aislamiento & purificación , Análisis de Secuencia de ADN , Adulto JovenRESUMEN
The aim of this study was to develop biodegradable films using fruit and vegetable residue (FVR) flour with different granulometry range and pectin levels. The FVR flour was divided in three fractions, according to their granulometric distribution: A (425-500⯵m), B (212-300⯵m) and C (<150⯵m). FVR presented heterogeneous particle size distribution and fibrous structure showing granular compounds adhered to the surface. The fiber contents decreased according to granulometry, whereas the protein content increased. The films obtained from FVR were malleable, homogeneous, yellowish, and presented high solubility (90%). The granulometry reduction and the pectin addition have significantly improved the viscosity and the yellow color of the film solutions (FS). There was decrease of solubility (50%) and improvement of the mechanical properties of the pectin-based films: decrease of elongation (16-30%) and increase of tensile strength (2.88⯱â¯0.79â¯MPa). The sorption isotherms of the pectin-FVR films evidenced the lower availability of polar groups able to work as water-sorption sites. Therefore, different residue fractions could have different applications depending on their particle size and composition, either as source of dietary fibers (the thickest fractions) or as raw material for film production.
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Plásticos Biodegradables/química , Harina/análisis , Frutas , Pectinas/química , Verduras , Fenómenos Químicos , Colorimetría , Fibras de la Dieta/análisis , Embalaje de Alimentos , Lípidos/análisis , Fenómenos Mecánicos , Microscopía Electrónica de Rastreo , Tamaño de la Partícula , Proteínas de Vegetales Comestibles/análisis , Reología , Almidón/química , Azúcares/análisis , Resistencia a la Tracción , Agua/químicaRESUMEN
Drosophila suzukii (Matsumura) is an invasive species originating in Southeast Asia and considered a severe pest in berry crops in several countries of the Northern Hemisphere and Europe. In South America, the species was first detected in 2013. The objective of the study was to monitor the seasonal activity of D. suzukii in commercial crops of blackberry, strawberry guava, surinam cherry, blueberry, and strawberry during two consecutive harvests and in three properties in the Southern region of Brazil during the 2015/2016 and 2016/2017 harvests, with the aid of traps baited with apple cider vinegar. The highest population peaks were observed during late spring to mid-fall in all areas and plant species studied. It was verified that temperature is the factor that most influenced the seasonal activity of D. suzukii in the field, promoting low catches of the species during winter. However, even during periods of low temperatures (winter period), the presence of D. suzukii in the crops was verified, demonstrating the species' ability to stay in place from year to year, surviving in alternative hosts such as Eriobotrya japonica, a common species in the region. The information on the time of the highest occurrence of the pest in different hosts presented in this study provides the basis for decision-making in relation to the management of D. suzukii, to avoid further economic damage.
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Productos Agrícolas , Drosophila/crecimiento & desarrollo , Frutas , Animales , Brasil , Femenino , Masculino , Dinámica Poblacional , Estaciones del AñoRESUMEN
OBJECTIVES: To analyze the effect of pulp-capping materials and resin composite light activation on strain and temperature development in the pulp and on the interfacial integrity at the pulpal floor/pulp-capping materials in large molar class II cavities. METHODS: Forty extracted molars received large mesio-occlusal-distal (MOD) cavity bur preparation with 1.0 mm of dentin remaining at the pulp floor. Four pulp-capping materials (self-etching adhesive system, Clearfil SE Bond [CLE], Kuraray), two light-curing calcium hydroxide cements (BioCal [BIO], Biodinâmica, and Ultra-Blend Plus [ULT], Ultradent), and a resin-modified glass ionomer cement- (Vitrebond [VIT], 3M ESPE) were applied on the pulpal floor. The cavities were incrementally restored with resin composite (Filtek Z350 XT, 3M ESPE). Thermocouple (n=10) and strain gauge (n=10) were placed inside the pulp chamber in contact with the top of the pulpal floor to detect temperature changes and dentin strain during light curing of the pulp-capping materials and during resin composite restoration. Exotherm was calculated by subtracting postcure from polymerization temperature (n=10). Interface integrity at the pulpal floor was investigated using micro-CT (SkyScan 1272, Bruker). The degree of cure of capping materials was calculated using the Fourier transform infrared and attenuated total reflectance cell. Data were analyzed using one-way analysis of variance followed by the Tukey test (α=0.05). RESULTS: Pulpal dentin strains (µs) during light curing of CLE were higher than for other pulp-capping materials ( p<0.001). During resin composite light activation, the pulpal dentin strain increased for ULT, VIT, and CLE and decreased for BIO. The pulpal dentin strain was significantly higher during pulp-capping light activation. The temperature inside the pulp chamber increased approximately 3.5°C after light curing the pulp-capping materials and approximately 2.1°C after final restoration. Pulp-capping material type had no influence temperature increase. The micro-CT showed perfect interfacial integrity after restoration for CLE and ULT; however, gaps were found between BIO and pulpal floor in all specimens. BIO had a significantly lower degree of conversion than ULT, VIT, and CLE. CONCLUSIONS: Light curing of pulp-capping materials caused deformation of pulpal dentin and increased pulpal temperature in large MOD cavities. Shrinkage of the resin composite restoration caused debonding of BIO from the pulpal floor.
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Resinas Compuestas/uso terapéutico , Pulpa Dental/efectos de la radiación , Dentina/efectos de la radiación , Curación por Luz de Adhesivos Dentales , Materiales de Recubrimiento Pulpar y Pulpectomía/efectos de la radiación , Temperatura Corporal , Pulpa Dental/efectos de los fármacos , Dentina/efectos de los fármacos , Cementos de Ionómero Vítreo/efectos adversos , Cementos de Ionómero Vítreo/uso terapéutico , Humanos , Técnicas In Vitro , Curación por Luz de Adhesivos Dentales/métodosRESUMEN
Modern electronic structure calculations are predominantly implemented within the super cell representation in which unit cells are periodically arranged in space. Even in the case of non-crystalline materials, defect-embedded unit cells are commonly used to describe doped structures. However, this type of computation becomes prohibitively demanding when convergence rates are sufficiently slow and may require calculations with very large unit cells. Here we show that a hitherto unexplored feature displayed by several 2D materials may be used to achieve convergence in formation- and adsorption-energy calculations with relatively small unit-cell sizes. The generality of our method is illustrated with Density Functional Theory calculations for different 2D hosts doped with different impurities, all of which providing accuracy levels that would otherwise require enormously large unit cells. This approach provides an efficient route to calculating the physical properties of 2D systems in general but is particularly suitable for Dirac-point materials doped with impurities that break their sublattice symmetry.
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The physiological responses of juvenile tambaqui (Colossoma macropomum) fed commercial feed supplemented with different concentrations of camu camu (Myrciaria dubia) were evaluated. The design was completely randomized, with treatments arranged in a factorial design with three proportions of camu camu (15%, 30% and 45%) and a control treatment (100% commercial diet), with four replicates per treatment. A total of 96 tambaqui specimens were used, with a mean initial weight of 11.69 ± 2.68 g and a mean length of 7.06 ± 0.44 cm. After 30 days, hematological parameters, metabolic variables, growth and fish swimming performance were evaluated. The different proportions of camu camu in the diet did not cause significant changes to the tambaqui's hematological parameters during the feeding period, except for hemoglobin (Hb) concentration and mean corpuscular hemoglobin concentration (MCHC) after the 30th day, and hematocrit (Ht) after the swimming stress test, which increased significantly (p < 0.05). The significant increases in metabolic variables, such as cortisol, glucose, proteins and triglycerides, and in hematologic variables after the Ucrit test reflect, respectively, biochemical adaptations for maintenance of the energy mobilization process and a regulatory necessity in tissue oxygen demand during intense exercise. Fish fed 15% and 30% camu camu gained the most weight and achieved the best swimming performance, respectively. The results for camu camu concentrations above 30% suggest a saturation of its intrinsic properties in the diet at this level and a loss of nutrients from the commercial feed replaced by the fruit, reducing productive performance and nutritional assimilation.