ABSTRACT Brazilian spotted fever, a zoonotic disease transmitted by ticks, is caused by Rickettsia rickettsii. We report a fulminant case of this zoonosis in a healthy 46-year-old military man in the urban region of Rio de Janeiro city, in October, 2021. Ticks and capybaras (Amblyomma sculptum, Hydrochoerus hydrochaeris, respectively) were identified in the military fields, pointing to the participation of this large synanthropic rodent, recognized as an efficient amplifier host of Rickettsia rickettsii in Brazil. As the military population is considered a risk group for spotted fever, it is necessary to alert health professionals to the importance of the early detection of the disease and its adequate management, mainly in populations that are particularly at risk of exposure to ticks, in order to avoid fatal outcomes.

SUMMARY: The amount and quality of carbon from forest litter present in the soil will depend on several factors, including species composition, management practices, plantation age, climatic conditions and soil texture, among several other factors. The aims of this research were to: i) quantify the labile organic carbon content in soils with Eucalyptus grandis plantations of the Mesopotamian region in Argentina and evaluate its relationship with the amount and type of litter; and ii) identify management, edaphic and environmental factors that may influence its variation. The study was performed on young and middle age plantations having soils with sandy and clayey texture located in the Gualeguaychú district, Entre Ríos, Argentina. To quantify the labile carbon in the soil, the soluble organic carbon was extracted with a 0.5M potassium sulfate solution. Soluble organic carbon concentration did not differ according to the age of the stands, with average values of 45.6 mg kg-1 in clay soils, and of 32.8 mg kg-1 in sandy soils, showing a positive association with clay content. The highest soluble organic carbon values were recorded during the summer months, and were positively related to the increases in the water-saturated pore space and the soil biological activity. We also verified a linear and positive relationship between the amount of initial fine litter and the increase of soluble organic carbon in the soil (R2 = 0.41). The reported results provide explicit ranges of variability for total organic carbon, soluble organic carbon and carbon fluxes at local level; thereby contributing to further characterize carbon modeling in forest systems.

RESUMEN: La cantidad y calidad de carbono del mantillo forestal que ingresa al suelo depende de varios factores, entre ellos la especie implantada, el manejo, edad de la plantación, las condiciones climáticas y la textura del suelo. Los objetivos de este trabajo fueron i) cuantificar el contenido de carbono orgánico lábil en suelos con plantaciones Eucalyptus grandis (Eucalyptus grandis) de la región mesopotámica y evaluar su relación con la cantidad y tipo del mantillo; e ii) identificar aquellos factores de manejo, edáficos y ambientales que influyen en su variación. Se trabajó sobre plantaciones jóvenes y de mediana edad en suelos de textura arenosa y arcillosa localizados en el Departamento de Gualeguaychú, Entre Ríos, Argentina. Con el fin de cuantificar el carbono lábil del suelo, se procedió a extraer el carbono orgánico soluble con una solución de sulfato de potasio 0,5M. Los valores de carbono orgánico soluble no difirieron según la edad de los rodales, con valores promedio de 45,6 mg kg-1 en los suelos arcillosos, y de 32,8 mg kg-1 en los arenosos, mostrando una asociación positiva con el contendido de arcilla. Los mayores valores de carbono soluble se registraron durante los meses estivales, relacionándose positivamente con los incrementos en el espacio poroso saturado con agua y con la actividad biológica del suelo. Pudo verificarse una relación lineal y positiva entre la cantidad de mantillo fino inicial y el incremento de carbono orgánico soluble en el suelo (R2= 0,41). Los resultados reportados cuantifican las existencias de carbono orgánico total, carbono orgánico soluble y flujos de carbono a nivel local, contribuyendo con información necesaria para el modelado del carbono en sistemas forestales.

ABSTRACT Nitrous oxide (N2O) is a greenhouse gas that contributes substantially to global climate change. The N2O soil emissions have a large uncertainty because of its low atmospheric concentration levels and enormous spatial and temporal variability, which hinders its correct field measurement. For this reason, there are many papers focused on improving the N2O measurements in the field, which focus on different parts of the measurement process. However, no studies have focused on determining the appropriate method, in terms of simplicity and precision, for the sample extraction from inside of the chambers and its transfer to the storage vials, although this step is key in the sampling process. This study aimed to assess and compare the accuracies of three simple and economical methods in transfer soil emitted N2O from inside of the chambers to the vials. For this, a highly accepted method (vacuum by manual pump) and two simpler alternative methods (gas exchange by displacement and vacuum by syringe) were compared. Thirty static chambers were assessed with the quantified N2O emission values varied from 0 to 450 µg m-2 h-1 of N-N2O. Out of the three assessed methods, the vacuum method through the use of a manual vacuum pump was the best to quantifying N2O soil emissions (capturing 57 % of the highest emission values), followed by the gas exchange method by displacement (30 %), and finally by the vacuum method by syringe extraction (13%).

ABSTRACT Stand density management diagrams (SDMD) provide a guide for forest density management taking into account stands attributes such as trees´ diameter or volume. One of the most common species planted in Pampean plains of Argentina is Eucalyptus viminalis for multiple objectives: solid wood use or firewood in local markets, pulp for cellulose industry and to provide services for agriculture and cattle raising (windbreaks or cattle refuge). The objective of this study was to gather the available production information /inventory data and to develop a first SDMD for estimating standing volume, biomass and canopy cover of E. viminalis as a tool for forest managers aiming at different plantation purposes. Data to develop the SDMD were obtained from 161 plots, distributed along a climate and soil gradient. We also generated two predictive equations capable of estimating dominant height from the diameter of the trees as well as canopy cover from stand basal area. As an example of application, the SDMD was used to estimate the wood production of three alternative systems: a) an unmanaged plantation (simulating a common practice in the region), b) a mixed production system such as an agroforestry system, and c) a plantation that maximizes wood biomass or volume production.

ABSTRACT In northeastern Argentina, very little is known about the impact of various techniques of management of residues from forest harvesting on soil properties. We carried out this study in two sites in Entre Ríos Province (Argentina): post-harvest of Eucalyptus grandis Hill ex Maiden stands in an Aquic Hapludert (S1) and in a Fluventic Hapludoll (S2). We analyzed the short-term effects of four techniques of residue management from eucalypt harvesting: extraction of residues (ER), conservation of residues (CR), burning of residues (BR=control treatment) and conservation of double the regular quantity of residues (CDQR), which consisted in adding residues from one plot to the adjacent one. Soils were sampled at 0-5 cm and 5-10 cm in 18 (S1) and 22 months (S2) after the techniques of management of residues were applied. Soil organic carbon (SOC), particulate organic carbon (POC), soil structure and saturated hydraulic conductivity (Ksat) were determined. Short-term effects of the techniques applied depended on the soil type and on the soil property analyzed. The main differences between soil properties were due to the effect of soil type on the size of the aggregates and on Ksat CR caused neither SOC increase nor POC changes, whereas CDQR and CR increased Ksat in S1, thus suggesting that the surface cover preserves porosity at the soil-atmosphere interphase. In contrast, S2 showed no significant differences between the effects of the techniques on soil properties. S1 showed large, stable aggregates and high Ksat, whereas S2 showed less stable structure. Site characteristics such as soil texture affect the short-term response of soil properties, thus indicating further evaluations of soil properties are needed to analyze the techniques of management of residue effects and give management recommendations based on the soil type.

RESUMEN En la región NE de Argentina existe poca información sobre el impacto que tienen las diferentes alternativas de manejo de residuos de la cosecha forestal sobre las propiedades edáficas. En este estudio se analizó el efecto a corto plazo de sistemas de manejo de residuos de la cosecha de Eucalyptus grandis Hill ex Maiden, sobre la concentración del carbono orgánico total del suelo (COT) y la fracción particulada (COP), su estado estructural y la conductividad hidráulica saturada. El estudio se desarrolló en dos sitios de la Provincia de Entre Ríos, Argentina, en un suelo Aquic Hapluderts (S1) y en un Fluventic Hapludolls (S2). Se aplicaron los siguientes tratamientos: 1. Extracción total de residuos (ER), 2. Conservación de residuos (CR), 3. Quema de residuos-testigo (QR), 4. Doble adición de residuos (DAR). El muestreo de suelos en las profundidades 0-5 cm y 5-10 cm se realizó a los 18 (S1) y a los 22 (S2) meses de aplicar los tratamientos. En el corto plazo, el efecto de los tratamientos dependió del tipo de suelo y de la variable analizada. Los contrastes más importantes se debieron al efecto de las características intrínsecas del suelo sobre el tamaño de los agregados y la conductividad hidráulica saturada. La conservación de residuos no aumentó la concentración de COT ni modificó la calidad de la materia orgánica medida a partir de COP. El suelo Aquic Hapluderts presentó agregados más grandes, más estables y una mayor Ksat en comparación con el Fluventic Hapludolls. En el Aquic Hapluderts se observó una mayor conductividad hidráulica saturada en los tratamientos con conservación de los residuos (DAR y CR), debido a que la cobertura preservaría el sistema poroso en la interfase suelo-atmosfera. El Fluventic Hapludolls fue menos estable y los tratamientos no modificaron significativamente el tamaño de los agregados ni la conductividad hidráulica saturada. Considerando que las características del sitio tienen efectos de corto plazo y las variables respuesta son afectadas de manera diferencial es necesario realizar un monitoreo de los parámetros evaluados para analizar las respuestas y las recomendaciones según el suelo.

An experiment was conducted under controlled conditions during 90 days to study the fortnightly response of two Eucalyptus hybrids (Eucalyptus grandis x Eucalyptus camaldulensis and Eucalyptus grandis x Eucalyptus tereticornis), subject to the effect of 3 water levels A: 1) normal watering; 2) cycles of 30 days of waterlogging followed by 15 days of normal irrigation; and 3) water table. At the same time, A2 and A3 treatments were combined with salinity levels (EC): <4 (control), 6 and 12 dS m-1. Biweekly total plant height and neck diameter were measured and mortality was recorded. After 90 days, leaf, branch and stem dry matter was determined along with foliar macronutrient concentration and soil fertility characterization in the pots. Plant growth and biomass significantly decreased with increasing salinity associated to flooding and high salty water table. Na foliar concentration increased whereas K decreased in treatments with moderate to high salinity. The effect on growth and biomass was less adverse when the solution was not saline. Saline solution added to the soil displaced exchangeable bases (Ca + Mg) and increased Na and PSI, but soil EC did not exceed 4 dS m-1. The hybrid E. grandis x E. camaldulensis showed higher growth, foliar concentration and biomass compared with E. grandis x E. tereticornis. This lower tolerance was also evidenced by earlier mortality.

Se realizó un experimento en condiciones controladas durante 90 días para estudiar la respuesta de dos combinaciones híbridas de Eucalyptus (Eucalyptus grandis x Eucalyptus camaldulensis y Eucalyptus grandis x Eucalyptus tereticornis), sometidos al efecto de 3 niveles de agua (A): 1) riego normal; 2) ciclos de 30 días de anegamiento seguido de 15 días de riego normal y 3) napa de agua permanente. A su vez, los tratamientos A2 y A3 se combinaron con 3 niveles de salinidad (CE): < 4 (control), 6 y 12 dS m-1. Quincenalmente se midió la altura y el diámetro del cuello de las plantas y se registró la mortalidad. A los 83 días se determinó materia seca en hojas, ramas y tallos, la concentración de macronutrientes foliares y se caracterizó la fertilidad del suelo de las macetas. El crecimiento de las plantas y la materia seca disminuyó significativamente con el aumento de la salinidad asociada a la inundación y la napa salina alta. La concentración foliar de Na aumentó y descendió la de K en los tratamientos con salinidad (moderada y alta). El efecto sobre el crecimiento y la biomasa fue menos adverso cuando la solución no fue salina. La solución salina agregada al suelo desplazó las bases intercambiables (Ca+Mg) y aumentó el Na y el PSI, pero la CE del suelo no superó los 4 dS m-1. El híbrido E. grandis x E. camaldulensis mostró mayores crecimientos, concentraciones foliares y biomasa en comparación con E. grandis x E. tereticornis. La menor tolerancia de este híbrido también se evidenció por la mortalidad más temprana.

Silvicultural treatments aim at increasing productivity in intervention stands. Bearing in mind the lack of prior information, the goals of this study are to assess the growth of Pinus radiata in the Southeast of the province of Buenos Aires, Argentina, and to promote the implementation of early intense pruning and thinning, assessing tree behavior at the individual and stand level. The trial was installed in a plantation of six years, with initial density of 1,111 plants ha-1, on a Hapludol ( <50 cm effective depth ) Treatments studied were: T1, control treatment, without intervention; T2, 50 % thinning, without pruning; T3, 75 % thinning, without pruning; T4, 50 % thinning, with pruning; and T5, 75 % thinning, with pruning. The trial was carried out in a six-year plantation, and measured yearly until the trees reached 13 years of age. Studied variables were: quadratic mean diameter, basal area and volume. Thinning had a significant and immediate impact on the production of wood at the stand level, whereas pruning did not led to significant growth losses, when applied in equivalent thinning intensities. Quadratic mean diameter increased differentially, with increases in the most intense thinning treatments. After 13 years, the most significant volume was found in T1 (189 m³ ha-1). When the growth of the 200 dominant trees was analyzed, treatments with 75 % thinning and with and without pruning differed statistically from the control. The intensity of 50 % thinning six years after plantation is the most recommended since it allows combining growth at the individual tree with a significant accumulation of volume remaining trees. Considering these soils do not compete with agricultural uses, these are interesting options to be considered as complementary productions.

Los tratamientos silvícolas orientados a la producción de madera de calidad tienen como finalidad concentrar la producción volumétrica en los mejores individuos. Atendiendo a la falta de información local previa, el objetivo del presente estudio fue evaluar el crecimiento de árboles individuales y de rodales. El ensayo se instaló en una plantación de seis años, con densidad inicial de 1.111 plantas ha-1, sobre un Hapludol (< 50 cm de profundidad efectiva). Los tratamientos fueron T1: testigo sin intervención; T2: 50 % de raleo (% del número total de plantas por hectárea), sin poda; T3: 75 % raleo, sin poda; T4: 50 % raleo, con poda y T5: 75 % raleo, con poda. Se medió anualmente hasta el año 13: diámetro medio cuadrático (dmc), área basal y volumen. A los 13 años el máximo volumen se observó en T1 (189,7 m³ ha-1). El raleo afectó significativamente la producción de madera en volumen a nivel de rodal, mientras que la poda sólo lo hizo en el tratamiento del 50 % de raleo a los 13 años. El dmc incrementó en forma diferencial, aumentando en los tratamientos de raleo más intensos. El crecimiento en dmc de los 200 árboles dominantes fue significativamente mayor en los tratamientos con 75 % de raleo (con y sin poda) que en el testigo. La intensidad de raleo del 50 % a los seis años del establecimiento de la plantación es el tratamiento recomendado, porque permite combinar crecimiento a nivel de árbol individual con una acumulación importante de volumen en los árboles remanentes.

ABSTRACT Different harvest techniques and residue management can cause changes in the quantity and quality in soil organic matter (OM). This study aims to assess changes in concentration and in the quality of the OM, in an Ultisol with differents forest residue managements at the beginning of the second rotation. The treatment was: a) elimination of harvest residues and forest floor, bare soil (RE), (b) burning of harvest residues and forest floor and subsequent plowing (IP), (c) maintenance of harvest residues and forest floor on the ground (CP). Soil samples were analyzed for determination of soil organic carbon (OC), carbon in the light fraction (LC) and carbon in the fulvic acids (FA), humic acids (HA) and humins (HU) fractions. The harvest residue conservation did not increase the OC or the LC. There was a loss of the more labile fraction (FA) particularly in IP. The treatments without forest residues and forest floor (RE and IP) show an increase in the degree of stabilization of the OM with an increase HU and in the ratio HA/FA.

RESUMEN Las distintas técnicas de cosecha y manejo de residuos pueden provocar cambios en la cantidad y calidad de la materia orgánica (MO) del suelo. El objetivo de este trabajo fue evaluar las modificaciones en la concentración y la calidad de la MO en un Ultisol con diferentes manejos de los residuos de la cosecha forestal del Pinus elliottii Engelm, al inicio de la segunda rotación. Los tratamientos analizados fueron: a) extracción manual de los residuos de la cosecha y del piso forestal, suelo descubierto (ER), b) quema de residuos y del mantillo, y laboreo con rastra (PI), c) conservación de residuos y del mantillo sobre el suelo (PC). Se determinó el carbono orgánico (CO) en todo el suelo y en las fracciones de ácidos fúlvicos (AF), ácidos húmicos (AH), huminas (HU) y en la fracción liviana (CL). La conservación de los residuos de la cosecha no aumentó el CO ni el CL. Se observó una pérdida de la fracción de ácidos fúlvicos (AF) particularmente en PI. Los tratamientos sin residuos forestales (ER y PI) muestran un aumento en el grado de estabilización de la MO con un incremento de las HU y de la relación CAH/CAF.

OBJETIVO: Avaliar a concentração mínima inibitória (CMI) de GTA frente a M. massiliense e a susceptibilidade a produtos alternativos para desinfecção de alto nível (DAN). MÉTODOS: Cepas de M. massiliense de origem clínica e de referência foram incluídas no estudo. As culturas ativadas foram submetidas a testes qualitativos com diluições de GTA (de 1,5% a 8%) e com soluções comerciais de ortoftaldeído (OPA) ou ácido peracético (PA), utilizando os tempos de exposição recomendados pela Agência Nacional de Vigilância Sanitária para DAN. RESULTADOS: Todas as cepas de referência e M. massiliense não-BRA100, obtida de escarro, foram susceptíveis às concentrações de GTA, e soluções de OPA e PA. As cepas de M. massiliense BRA100 apresentaram CMI de 8% para GTA e foram susceptíveis a OPA e PA. CONCLUSÃO: M. massiliense BRA100 é resistente a altas concentrações de GTA (até 7%), o que demonstra que esse composto não é eficaz, e deve ser substituído por OPA ou PA nos processos de DAN.

PURPOSE: To evaluate the minimum inhibitory concentration (MIC) of GTA against these microorganisms and alternative disinfectants for high-level disinfection (HLD). METHODS: Reference mycobacteria and clinical M. massiliense strains were included in this study. Active cultures were submitted to susceptibility qualitative tests with GTA dilutions (ranging from 1.5% to 8%), and commercial orthophthaldehyde (OPA) and peracetic acid (PA) - based solutions, during the period of exposure as recommended by National Agency of Sanitary Surveillance for HLD. RESULTS: All reference and M. massiliense non-BRA100 strains, recovered from sputum, were susceptible to any GTA concentration, OPA and PA solutions. M. massiliense BRA100 strains presented MIC of 8% GTA and were susceptible to OPA and PA. CONCLUSION: M. massiliense BRA100 strain is resistant to high GTA concentrations (up to 7%), which proves that this product is non-effective against specific rapidly growing mycobacteria and should be substituted by OPA or PA - based solutions for HLD.

A úlcera de Buruli, uma doença infecciosa causada pela Mycobacterium ulcerans (M. ulcerans),é a terceira micobacteriose em ocorrência, após a hanseníase e a tuberculose. Essa micobacteriose atípica tem sido relatada em mais de 30 países, principalmente, nos que têm climas tropicais e subtropicais, mas a sua epidemiologia permanece obscura. Recentemente, os primeiros casos autóctones do Brasil foram relatados, fazendo com que dermatologistas brasileiros estejam atentos a esse diagnóstico. O quadro clínico varia: nódulos, áreas de edema, placas, mas a manifestação mais típica é uma grande úlcera, que ocorre, em geral, nas pernas ou nos braços. Apesar do amplo conhecimento quanto ao seu quadro clínico em países endêmicos, nas outras áreas, esse diagnóstico pode passar despercebido. Assim, médicos devem ser orientados quanto à úlcera de Buruli, pois o diagnóstico precoce, o tratamento específico e a introdução de cuidados na prevenção de incapacidades são essenciais para uma boa evolução.

Buruli ulcer, an infectious disease caused by Mycobacterium ulcerans, is the third most prevalent mycobacteriosis, after tuberculosis and leprosy. This atypical mycobacteriosis has been reported in over 30 countries, mainly those with tropical and subtropical climates, but its epidemiology remains unclear. The first autochthonous cases of infection in Brazil have recently been described, making this diagnosis important for Brazilian dermatologists. Clinical manifestations vary from nodules, areas of edema, and plaques, but the most typical presentation is a large ulcer, usually in the limbs. Despite considerable knowledge about its clinical manifestations in some endemic countries, in other areas the diagnosis may be overlooked. Therefore, physicians should be educated about Buruli ulcer, since early diagnosis and treatment, including measures to prevent disability, are essential for a good outcome.

ABSTRACT The present work was developed in the West of Buenos Aires Province (Argentina) with the objective of adjusting functions of biomass of individual trees, in their different compartments and in the understorey. Stands of Eucalyptus viminalis Labill. were identified, with ages between 4 and 14 years-old. Twenty-one individuals were felled with diameters ranging from 9,2 to 32,5 cm. Simple and multiple regression models were developed and volume, branch leaf and stem biomass were estimated. The best volume equations were based on lineal models and the most adequate behavior was obtained with d2. To estimate leaf, branch and stem, ln-ln models have been suggested, with diameter and h or only diameter. The leaf biomass presented the weakest adjustment. The distribution of trees biomass agrees with the bibliography. The proportion of crown biomass decreases with age; on the other hand, the proportion of stem biomass increases with age.

RESUMEN El presente trabajo se desarrolló en el oeste de la provincia de Buenos Aires, Argentina con el objetivo de ajustar funciones de biomasa de árboles individuales y determinar la biomasa en diferentes compartimientos de la planta y el sotobosque. Se identificaron rodales de Eucalyptus viminalis Labill. Cuyas edades oscilaron entre 4 y 14 años. Se apearon 21 árboles con diámetros entre 9,2 y 32,5 cm. Se desarrollaron regresiones simples y múltiples y se estimó el volumen, la biomasa en ramas, hojas y fuste. Las ecuaciones de volumen de mejor comportamiento son basadas en modelos lineales en su forma normal, y el modelo más adecuado fue el que incorporó al d2 (R2 = 0,92). Para la estimación de la biomasa en hojas, ramas, copa y fuste se recomienda los modelos ln-ln que consideran el d y h o solo el d. El componente de la biomasa en hojas presentó una estimación más débil. La distribución de la biomasa en los individuos sigue el patrón de desarrollo que se encuentra en la bibliografía. La proporción de la biomasa en la copa disminuye con la edad, contrariamente a lo sucedido con el fuste.

The objective of this work was to evaluate the effect of different harvest residue management techniques for Pinus elliotii Engelm on the indices of a Kandiudult soil in Misiones, Argentina under conditions of high temperature and precipitation. The treatments were as follows: T1) manual extraction of harvest residues and reforestation; T2) burning and reforestation; T3) residue conservation and reforestation; and T4) residue conservation and development of a secondary forest. The statistical design was a completely randomized block with four replicates in blocks of 840 m². The soil samples were removed a year and a half after introducing the treatments, since short-term monitoring is important given that the first four years are key for pine plantations in this region. The total removal of residue (T1) produced in lower values of total carbon (Ct) (P < 0.05). Burning (T2) in the short term produced a significant increment of extractable phosphorus (Pe) (P < 0.05). The conservation of residue provoked a significant increase in total nitrogen (Nt), equivalent to burning, and the highest values of total carbon (Ct) and light carbon (Cl) (P < 0.05).

El objetivo de este trabajo fue evaluar el efecto de diferentes técnicas de manejo de residuos de Pinus ellioti Engelm en índices de calidad de suelo en un Kandiudult de Misiones, Argentina, en condiciones de altas temperaturas y precipitaciones. Los tratamientos fueron: T1) extracción manual de los residuos y reforestación; T2) quema y reforestación; T3) conservación de los residuos y reforestación; T4) conservación de los residuos y desarrollo de bosque secundario. El diseño estadístico fue en bloques completamente al azar con cuatro repeticiones, en bloques de 840 m². Las muestras de suelo fueron extraídas un año y medio después de implantados los tratamientos, por ser importante el monitoreo a corto plazo, dado que los cuatro primeros años son clave en las plantaciones de pinos en esta región . La remoción total de los residuos se tradujo en menores valores de las formas de carbono total (Ct) (P < 0,05). La quema, a corto plazo, produjo un aumento significativo de fósforo extractable (Pe) (P < 0,05). La conservación de los residuos provocó un aumento significativo de nitrógeno total (Nt), equivalente al de la quema, y valores más altos de carbono total (Ct) y carbono liviano (Cl) (P < 0,05).