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RESUMO A distribuição radicular de espécies florestais tem sido pouco estudada, principalmente em regiões tropicais. Neste trabalho são apresentados os resultados de um estudo sobre o sistema radicular de duas nativas (Carapa guianensis e Cedrelinga catenaeformis) e duas exóticas (Eucaliptus deglupta e Gmelina arborea), plantadas em experimento ao norte de Manaus. Por meio de escavações foram registrados o diâmetro, o comprimento e feito um croqui de localização das raízes de oito árvores. Em plantas diferentes, de três destas espécies, foi feita uma coleta de raízes de diâmetro maior do que 5 mm, sendo determinada sua massa de matéria seca. Os resultados mostraram que C. guianensis, C. catenaeformis e E. deglupta têm arquitetura semelhante, com pivotantes bifurcadas, ao contrário de G. arborea, que apresentou um sistema sem pivotante, com ramificações radiais a partir da base do tronco. Esses dados permitem uma melhor compreensão da ocupação do solo por estas espécies, bem como um planejamento mais adequado de plantios destas espécies, na região.

Abstract The Amazon River mobilizes organic carbon across one of the world's largest terrestrial carbon reservoirs. Quantifying the sources of particulate organic carbon (POC) to this flux is typically challenging in large systems such as the Amazon River due to hydrodynamic sorting of sediments. Here, we analyze the composition of POC collected from multiple total suspended sediment (TSS) profiles in the mainstem at Óbidos, and surface samples from the Madeira, Solimões and Tapajós Rivers. As hypothesized, TSS and POC concentrations in the mainstem increased with depth and fit well to Rouse models for sediment sorting by grain size. Coupling these profiles with Acoustic Doppler Current Profiler discharge data, we estimate a large decrease in POC flux (from 540 to 370 kg per second) between the rising and falling stages of the Amazon River mainstem. The C/N ratio and stable and radiocarbon signatures of bulk POC are less variable within the cross‐section at Óbidos and suggest that riverine POC in the Amazon River is predominantly soil‐derived. However, smaller shifts in these compositional metrics with depth, including leaf wax n‐alkanes and fatty acids, are consistent with the perspective that deeper and larger particles carry fresher, less degraded organic matter sources (i.e., vegetation debris) through the mainstem. Overall, our cross‐sectional surveys at Óbidos highlight the importance of depth‐specific sampling for estimating riverine export fluxes. At the same time, they imply that this approach to sampling is perhaps less essential with respect to characterizing the composition of POC sources exported by the river.

RESUMO O estudo das relações entre o solo e a floresta tem se mostrado importante para a compreensão, conservação e manejo destes recursos. Além disso, se constitui em instrumento valioso para o planejamento do território. A região ao norte de Manaus faz parte de um sub-domínio ecológico, onde as características edáficas e vegetacionais mostram diferenças ao longo de platôs, vertentes intermediárias e fundos de vales. Com o objetivo de avaliar o padrão destas mudanças, foram feitas descrições morfológicas de oito perfis de solo, em duas toposequências. Ao lado de cada perfil, foi feito também o estudo de um transecto, para a caracterização do tipo florestal presente, com o registro do nome vulgar e coleta de material botânico para posterior identificação. No sentido do platô para as posições mais baixas do relevo, se observa uma diferenciação da morfologia do solo com um aumento gradual no percentual de areia. As características edáficas mostram-se cada vez mais limitantes para o crescimento vegetal. No platô os solos apresentam uma textura argilosa ao longo de todo o perfil, tomando-se franco argilo arenoso a argilo arenoso nas vertentes, até chegar ao nível mais baixo da paisagem, onde os perfis se apresentam arenosos. Os resultados mostram também uma diferenciação progressiva no tipo de vegetação. A área basal decresce no sentido do platô para as áreas mais baixas. As florestas presentes em ambientes hídromórficos apresentam também uma relação estreita entre o tipo vegetacional e as características morfológicas do solo. São propostos oito tipos de paisagens florestais, que deverão subsidiar o planejamento, as intervenções e o manejo dos recursos naturais presentes na região.

RESUMO Até o ano de 1968, o Brasil possuía uma lista de espécies da flora ameaçadas de extinção, produzida pelo Instituto Brasileiro de Desenvolvimento Florestal, que relacionava apenas 12 espécies vegetais, sem menção às suas categorias. Em 1994, a Comissão para Sobrevivência de Espécies da União Internacional para a Conservação da Natureza (IUCN) classificava, em 11 diferentes categorias de conservação, as espécies em via de extinção. Entretanto, tal nivelamento não parece ser coerente nem uniforme, pois há autores que utilizam nomenclaturas diferentes para categorias com iguais definições. No presente estudo discute-se as diferentes categorias e definições adotadas, bem como a ausência de coerência no uso destas definições. Foram analisadas sete publicações sobre a classificação das categorias de conservação de espécies vegetais em vias de extinção, publicadas por instituições privadas e governamentais entre 1992 e 1997. Para evitar o conflito de informações sobre uma mesma espécie, seria necessário estabelecer meios para que as descrições contraditórias fossem analisadas por uma equipe multidisciplinar de ecólogos, geógrafos, botânicos, fitossociólogos etc., com condições de avaliar, de forma precisa, a que categoria de conservação pertence cada espécie. As divergências nas atribuições das categorias de conservação podem limitar as ações conservacionistas necessárias à preservação de uma espécie da flora. Contudo, apesar de suas limitações e discrepâncias, consistem em veículos que auxiliam o desenvolvimento de atividades de preservação, sobretudo, no que se refere às espécies que sofrem exploração seletiva extrativista.

RESUMO Este trabalho visa a elaboração de um catálogo com a localização e identificação das árvores presentes no campus da UFRRJ, bem como estudo das principais características plásticas destas, de modo a permitir uma maior percepção do componente arbóreo pela comunidade universitária. Foi realizado percorrendo-se a quadra dos alojamentos, registrando a localização de cada indivíduo observado, suas características plásticas e coletando-se o material botânico para posterior identificação em herbário. Foram observadas 212 árvores na área de estudo, pertencentes a 37 espécies. Apesar desta diversidade, três espécies apresentam quase a metade do número de árvores da área e dois tipos de estrutura somam 75% dos indivíduos. Sugere-se a recomposição de uma parte da quadra, com o plantio de árvores de maneira mais integrada e com características plásticas que permitam uma unidade cênica.

En este artículo se reconstruye una polémica suscitada en la ciudad de Buenos Aires en 1891 a propósito de unas infracciones contra la ley de ejercicio de la medicina, cometidas presuntamente por dos actores que se especializaban en el tratamiento de la lombriz solitaria, un médico extranjero y un sanador no diplomado. En base al examen de las fuentes relativas a ese caso, el texto propone una reflexión en torno a tres tópicos. En primer lugar, se rastrean las múltiples ofertas curativas disponibles para el abordaje de esa afección, pues se entiende que considerarlas ayuda a comprender de modo más certero los componentes de aquella polémica. En segundo lugar, se documentan los antecedentes de los actores sociales involucrados en ese conflicto, bajo el supuesto de que se trata de un caso ilustrativo de las trayectorias de muchos otros agentes del mundo de la salud de esos años. En tercer lugar, se recupera la discusión referida a las relaciones de complementariedad o de negociación entabladas entre la medicina diplomada y sus competidores no autorizados.

Abstract Background Asplenia vaccination is employed before ABO‐incompatible (ABOi) transplantation in case splenectomy is needed. Pneumococcal vaccines have been reported, in different patient groups, to increase anti‐A/B titers, through cross‐reactivity to shared polysaccharide epitopes. We investigated the impact of pretransplant asplenia vaccinations on anti‐A/B antibody titers in prospective ABOi renal transplant recipients. Methods Published asplenia vaccine microbial structures were reviewed to assess expression of A/B antigens. All patients who underwent ABOi transplantation at Monash Medical Centre with anti‐A/B titers taken either side of asplenia vaccination were included in a retrospective cohort study between 2007 and 2021. Patients with paired titers without intervening vaccination were included as controls. Paired titers were compared within groups. Results A and B antigens were found to be expressed by vaccine specific pneumococcal serotypes. Thirty‐nine ABOi renal transplant recipients received vaccination including at least one pneumococcal vaccine. The most common donor to recipient combination was A1 to O. The median pre‐ and postvaccination anti‐A/B titers were 1:32 and there was no significant change in titers following vaccination (median change in titer 0 dilutions, range –2 to 3, P = 0.43). The same findings were apparent in the control group (n = 20). There was no significant change in titer by donor blood group or vaccine type. No transplants were canceled or delayed by a rise in anti‐A/B titers postvaccination. Conclusion Pneumococcal vaccination had no clinically relevant impact on anti‐A/B titers before ABOi transplantation in this cohort. These results provide reassurance regarding the safety of asplenia vaccination before ABOi transplantation.

Abstract In this work, it is proposed the development a new monopole directional antenna, bioinspired in elliptical leaf, with cut by golden ratio, for 4G band application, by the use of the technique of the cut of the radiating element for the increasing of the antenna perimeter, being the first work to use this technique in a bioinspired antenna, promotes resonance frequency turned, and reconfiguring of the antenna parameters as bandwidth, radiation pattern and gain, with the use of the reflector near to the group plane, without the insertion of active devices as the pin diode or change in radiating element. The shape antenna is generated by Gielis formula, built in FR4 substrate, with cuts calculated by golden ratio. To compare the results of the bioinspired monopole on the elliptical sheet, a square-shaped monopole antenna was designed, simulated and measured, the structures were designed in the MATLAB software version 2015(b) and the simulations were performed in the Ansys software version 2016. In the results compared between the square monopole and the bioinspired antenna in the elliptical sheet, it can be seen that the measured bioinspired antenna, compared to the square monopole, presented a bandwidth reduction of 77.27%, a more compact structure, with a reduction of 98%, covering the wireless local area network, and long-time evolution 4G at 2.5 GHz. The proposed technique uses a reflector on the ground plane, to change the parameters of the monopole planar antenna, of omnidirectional radiation pattern to a directional, maintaining the characteristics of the broadband, half-power beamwidth great than 100°, with high current density, and similar gain of a directional antenna. From the results, it has been observed that the elliptical leaf monopole antenna shows broadband characteristics, with a half-power beamwidth of 128°, wideband, the bandwidth of 500 MHz, a gain of 6.28 dBi, a current density of 13.01 A/m2, and circular polarization.

Modern hybrid electric vehicles (HEVs) like the fourth generation of Toyota Prius incorporate multiple planetary gears (PG) to interconnect various power components. Previous studies reported that increasing the number of planetary gears from one to two reduces energy consumption. However, these studies did not compare one PG and two PGs topologies at their optimal operation. Moreover, the size of the powertrain components are not the same and hence the source of reduction in energy consumption is not clear. This paper investigates the effect of the number of planetary gears on energy consumption under optimal operation of the powertrain components. The powertrains with one and two PGs are considered and an optimal simultaneous torque distribution and mode selection strategy is proposed. The proposed energy management strategy (EMS) optimally distributes torque demands amongst the power components whilst also controlling clutches (i.e., mode selection). Results show that increasing from one to two PGs reduces energy consumption by 4%.

Increases in hydrological extremes, including drought, are expected for Amazon forests. A fundamental challenge for predicting forest responses lies in identifying ecological strategies which underlie such responses. Characterization of species-specific hydraulic strategies for regulating water-use, thought to be arrayed along an 'isohydric–anisohydric' spectrum, is a widely used approach. However, recent studies have questioned the usefulness of this classification scheme, because its metrics are strongly influenced by environments, and hence can lead to divergent classifications even within the same species. Here, we propose an alternative approach positing that individual hydraulic regulation strategies emerge from the interaction of environments with traits. Specifically, we hypothesize that the vertical forest profile represents a key gradient in drought-related environments (atmospheric vapor pressure deficit, soil water availability) that drives divergent tree water-use strategies for coordinated regulation of stomatal conductance (gs) and leaf water potentials (ΨL) with tree rooting depth, a proxy for water availability. Testing this hypothesis in a seasonal eastern Amazon forest in Brazil, we found that hydraulic strategies indeed depend on height-associated environments. Upper canopy trees, experiencing high vapor pressure deficit (VPD), but stable soil water access through deep rooting, exhibited isohydric strategies, defined by little seasonal change in the diurnal pattern of gs and steady seasonal minimum ΨL. In contrast, understory trees, exposed to less variable VPD but highly variable soil water availability, exhibited anisohydric strategies, with fluctuations in diurnal gs that increased in the dry season along with increasing variation in ΨL. Our finding that canopy height structures the coordination between drought-related environmental stressors and hydraulic traits provides a basis for preserving the applicability of the isohydric-to-anisohydric spectrum, which we show here may consistently emerge from environmental context. Our work highlights the importance of understanding how environmental heterogeneity structures forest responses to climate change, providing a mechanistic basis for improving models of tropical ecosystems. [ABSTRACT FROM AUTHOR]

We report for the first time the snake Thamnodynastes almae Franco & Ferreira, 2002 in Piauí, northeastern Brazil. Our record is based on two specimens and comprises the 17th known locality for the species. The new record represents the northernmost and westernmost locality, at the limit between the Caatinga and the Maranhão Babaçu Forest ecoregions, and extends this species’ geographic distribution 495 km from Milagres, state of Ceará. Updated distribution maps and images of preserved specimens are provided.

Abstract This paper presents the characterization of dielectric properties (dielectric permittivity and dielectric loss factor) of Tommy Atkins mango (Mangifera indica L), a fruit produced in several regions of Brazil, of great economic importance. The fruits were characterized according to their maturation index, by probe method, and identified by the yellowish tone in their bark. The results allowed correlating the dielectric characteristics of the fruit with the physicochemical transformations that occurred in the maturation process of the mango Tommy. It was also verified a greater variation in the frequencies below 1 GHz, with the maturation indicated by the dielectric signature on the fifth day after the harvest. From these results, we can observe the use of electromagnetic materials and techniques in the solution and optimization of processes in agriculture can improve the quality of products consumed or suggesting best practices to the productive sector.

This contribution explores in a new statistical perspective the antibody responses to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in 141 coronavirus disease 2019 (COVID-19) patients exhibiting a broad range of clinical manifestations. This cohort accurately reflects the characteristics of the first wave of the SARS-CoV-2 pandemic in Italy. We determined the IgM, IgA, and IgG levels towards SARS-CoV-2 S1, S2, and NP antigens, evaluating their neutralizing activity and relationship with clinical signatures. Moreover, we longitudinally followed 72 patients up to 9 months postsymptoms onset to study the persistence of the levels of antibodies. Our results showed that the majority of COVID-19 patients developed an early virus-specific antibody response. The magnitude and the neutralizing properties of the response were heterogeneous regardless of the severity of the disease. Antibody levels dropped over time, even though spike reactive IgG and IgA were still detectable up to 9 months. Early baseline antibody levels were key drivers of the subsequent antibody production and the long-lasting protection against SARS-CoV-2. Importantly, we identified anti-S1 IgA as a good surrogate marker to predict the clinical course of COVID-19. Characterizing the antibody response after SARS-CoV-2 infection is relevant for the early clinical management of patients as soon as they are diagnosed and for implementing the current vaccination strategies.

Positioning systems are used in a wide range of applications which require determining the position of an object in space, such as locating and tracking assets, people and goods; assisting navigation systems; and mapping. Indoor Positioning Systems (IPSs) are used where satellite and other outdoor positioning technologies lack precision or fail. Ultra-WideBand (UWB) technology is especially suitable for an IPS, as it operates under high data transfer rates over short distances and at low power densities, although signals tend to be disrupted by various objects. This paper presents a comprehensive study of the precision, failure, and accuracy of 2D IPSs based on UWB technology and a pseudo-range multilateration algorithm using Time Difference of Arrival (TDoA) signals. As a case study, the positioning of a 4×4m2 area, four anchors (transceivers), and one tag (receiver) are considered using bitcraze’s Loco Positioning System. A Cramér–Rao Lower Bound analysis identifies the convex hull of the anchors as the region with highest precision, taking into account the anisotropic radiation pattern of the anchors’ antennas as opposed to ideal signal distributions, while bifurcation envelopes containing the anchors are defined to bound the regions in which the IPS is predicted to fail. This allows the formulation of a so-called flyable area, defined as the intersection between the convex hull and the region outside the bifurcation envelopes. Finally, the static bias is measured after applying a built-in Extended Kalman Filter (EKF) and mapped using a Radial Basis Function Network (RBFN). A debiasing filter is then developed to improve the accuracy. Findings and developments are experimentally validated, with the IPS observed to fail near the anchors, precision around ±3cm, and accuracy improved by about 15cm for static and 5cm for dynamic measurements, on average.

Architecture is one of the first expressions of human culture. Its development has been a constant throughout the centuries, especially since the appearance of sedentarization processes, when the combination of different materials to improve the durability and isolation of the constructions is observed. The execution of coverings for walls and other domestic structures made smooth surfaces available, on which to express the ideological codes of human communities or simply to develop their aesthetic values. In this paper, a plastered building fragment with remains of paint from the Cabezo Redondo Bronze Age site (Villena, Alicante) is presented. This is the first decorated fragment of render documented in the settlement. The analysis of the archaeological context in which it appeared allows us to relate it to other similar evidence documented in other Bronze Age sites, inside and outside the area of the El Argar culture. On this fragment a wide set of non-destructive analyses have been developed to preserve its patrimonial value. Firstly, a macroscopic observation with the aim of making a detailed description. Furthermore, mineralogical studies have been carried out to address the composition of the covering and the ornamental band, but also the geological characterization of the deposit environment, to contextualize the origin of the materials used. These analyses have also made possible to explore the manufacturing and maintenance processes of the domestic structures built in Cabezo Redondo, through the study of this singular element from these diverse and complementary approaches. RESUMEN: La arquitectura es una de las primeras expresiones de la cultura humana. Su desarrollo ha sido una constante a lo largo de los siglos, especialmente a partir de la aparición de los procesos de sedentarización, momento en el cual se aprecia la combinación de diferentes materiales destinados a mejorar la durabilidad y el aislamiento de las construcciones. El desarrollo de revestimientos de las paredes permitió la aparición de superficies lisas sobre las cuales plasmar los códigos ideológicos de las comunidades humanas o, simplemente, desarrollar sus valores estéticos. En este trabajo se presenta el primer fragmento documentado de revestimiento con restos de pintura procedente del yacimiento de la Edad de Bronce de Cabezo Redondo (Villena, Alicante), sobre el cual se han desarrollado un amplio conjunto de analíticas no destructivas con el objetivo de determinar no solo sus características físicas y de composición, sino también la intencionalidad ornamental de la pintura.

The Amazon River mobilizes organic carbon across one of the world's largest terrestrial carbon reservoirs. Quantifying the sources of particulate organic carbon (POC) to this flux is typically challenging in large systems such as the Amazon River due to hydrodynamic sorting of sediments. Here, we analyze the composition of POC collected from multiple total suspended sediment (TSS) profiles in the mainstem at Óbidos, and surface samples from the Madeira, Solimões and Tapajós Rivers. As hypothesized, TSS and POC concentrations in the mainstem increased with depth and fit well to Rouse models for sediment sorting by grain size. Coupling these profiles with Acoustic Doppler Current Profiler discharge data, we estimate a large decrease in POC flux (from 540 to 370 kg per second) between the rising and falling stages of the Amazon River mainstem. The C/N ratio and stable and radiocarbon signatures of bulk POC are less variable within the cross‐section at Óbidos and suggest that riverine POC in the Amazon River is predominantly soil‐derived. However, smaller shifts in these compositional metrics with depth, including leaf wax n‐alkanes and fatty acids, are consistent with the perspective that deeper and larger particles carry fresher, less degraded organic matter sources (i.e., vegetation debris) through the mainstem. Overall, our cross‐sectional surveys at Óbidos highlight the importance of depth‐specific sampling for estimating riverine export fluxes. At the same time, they imply that this approach to sampling is perhaps less essential with respect to characterizing the composition of POC sources exported by the river. Plain Language Summary: The Amazon River transports one of the largest quantities of freshwater organic carbon into the Atlantic Ocean. In this study, we collected suspended particles at different depths within a cross‐section of the Amazon River mainstem during the rising and falling stages of the river's hydrological cycle. We analyzed the organic carbon, nitrogen, grain size, and leaf‐derived compounds in these particles, and integrated water velocity measurements to calculate the quantity of carbon in particle form moving through the river at these two stages. The analyses showed that large, dense particles concentrate with depth in the Amazon River mainstem. The composition of these particles is relatively homogenous, but slight variations in metrics like carbon‐to‐nitrogen ratio, age derived from carbon‐dating, and leaf waxes imply that less degraded sources of organic carbon are found in the deeper and coarser grained particles. Overall, the data suggest that the majority of Amazon River particulate organic carbon comes from a mixture of soil organic carbon washing in from different landscapes and soil depth horizons. A globally significant quantity of this carbon will get buried in the Atlantic Ocean, forming a long‐term carbon sink. Key Points: Amazon River suspended sediments show little variation in organic carbon composition with depth despite hydrodynamic sortingEstimated particulate organic carbon fluxes range from 370 to 540 kg per second during the falling and rising stages, respectivelyThe majority of Amazon River particulate organic carbon exported from the mainstem at Óbidos is soil‐derived [ABSTRACT FROM AUTHOR]

Rivers are thought to be the largest source of the recalcitrant and abundant black carbon in the ocean. Here, Wagner and colleagues find distinct pools of black carbon between rivers and the open ocean, challenging the long-held assumption that marine black carbon is of terrestrial origin.

Acute and chronic dermatological injuries need rapid tissue repair due to the susceptibility to infections. To effectively promote cutaneous wound recovery, it is essential to develop safe, low-cost, and affordable regenerative tools. Therefore, we aimed to identify the biological mechanisms involved in the wound healing properties of the glycosaminoglycan dermatan sulfate (DS), obtained from ascidian Styela plicata, a marine invertebrate, which in preliminary work from our group showed no toxicity and promoted a remarkable fibroblast proliferation and migration. In this study, 2,4-DS (50 µg/mL)-treated and control groups had the relative gene expression of 84 genes participating in the healing pathway evaluated. The results showed that 57% of the genes were overexpressed during treatment, 16% were underexpressed, and 9.52% were not detected. In silico analysis of metabolic interactions exhibited overexpression of genes related to: extracellular matrix organization, hemostasis, secretion of inflammatory mediators, and regulation of insulin-like growth factor transport and uptake. Furthermore, in C57BL/6 mice subjected to experimental wounds treated with 0.25% 2,4-DS, the histological parameters demonstrated a great capacity for vascular recovery. Additionally, this study confirmed that DS is a potent inducer of wound-healing cellular pathways and a promoter of neovascularization, being a natural ally in the tissue regeneration strategy.