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In this study, the physiological performance and fruit quality responses of the highbush blueberry (Vaccinium corymbosum) cultivar Legacy to high temperatures (HTs) were evaluated in a field experiment. Three-year-old V. corymbosum plants were exposed to two temperature treatments between fruit load set and harvest during the 2022/2023 season: (i) ambient temperature (AT) and (ii) high temperature (HT) (5 °C ± 1 °C above ambient temperature). A chamber covered with transparent polyethylene (100 µm thick) was used to apply the HT treatment. In our study, the diurnal temperature was maintained with a difference of 5.03 °C ± 0.12 °C between the AT and HT treatments. Our findings indicated that HT significantly decreased CO2 assimilation (Pn) by 45% and stomatal conductance (gs) by 35.2% compared to the AT treatment. By contrast, the intercellular CO2 concentration (Ci) showed higher levels (about 6%) in HT plants than in AT plants. Fruit quality analyses revealed that the fruit weight and equatorial diameter decreased by 39% and 13%, respectively, in the HT treatment compared to the AT treatment. By contrast, the firmness and total soluble solids (TSS) were higher in the HT treatment than in the AT treatment. Meanwhile, the titratable acidity showed no changes between temperature treatments. In our study, Pn reduction could be associated with stomatal and non-stomatal limitations under HT treatment. Although these findings improve our understanding of the impact of HTs on fruit growth and quality in V. corymbosum, further biochemical and molecular studies are need.

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Salicylic acid (SA) application is a promising agronomic tool. However, studies under field conditions are required, to confirm the potential benefits of SA. Thus, SA application was evaluated under field conditions for its effect on abscisic acid levels, antioxidant related-parameters, fruit quality, and yield in Aristotelia chilensis subjected to different levels of irrigation. During two growing seasons, three-year-old plants under field conditions were subjected to full irrigation (FI: 100% of reference evapotranspiration (ETo), and deficit irrigation (DI: 60% ETo). During each growth season, a single application of 0.5 mM SA was performed at fruit color change by spraying fruits and leaves of both irrigation treatments. The results showed that DI plants experienced moderate water stress (-1.3 MPa), which increased ABA levels and oxidative stress in the leaves. The SA application facilitated the recovery of all physiological parameters under the DI condition, increasing fruit fresh weight by 44%, with a 27% increase in fruit dry weight, a 1 mm increase in equatorial diameter, a 27% improvement in yield per plant and a 27% increase in total yield, with lesser oxidative stress and tissue ABA levels in leaves. Also, SA application significantly increased (by about 10%) the values of fruit trait variables such as soluble solids, total phenols, and antioxidant activity, with the exceptions of titratable acidity and total anthocyanins, which did not vary. The results demonstrated that SA application might be used as an agronomic strategy to improve fruit yield and quality, representing a saving of 40% regarding water use.

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In ruminants, diet composition has a positive correlation with heat production, which can influence thermoregulation, energy expenditure and, consequently, animal performance. The objective of this work was to evaluate the effects of climatic conditions and supplementation based on palm kernel cake, on the thermoregulation of crossbred buffaloes in the eastern Amazon. The research was carried out at Embrapa Amazônia Oriental (01°26' S and 48°24' W), Belém, Pará, and lasted 12 months (representing the entire year). Twenty-four buffaloes, females, with initial age and an average weight of 54 ± 7 months and 503.1 ± 23 kg, respectively, non-pregnant, non-lactating and clinically healthy were used, divided into four treatments based on the supplementation content of the palm cake (%DM) in relation to their body weight (%): 0, 0.25, 0.50 and 1.0. The animals were kept in paddocks with Brachiaria brizantha (cv. Marandu), in a rotating system, with water to drink and mineral salt ad libitum. Equipment was installed to record environmental data (temperature and relative humidity, dew point temperature, wet bulb and black globe) and physiological data: rectal temperature (RT); respiratory rate (RR); and body surface temperature (BST), recorded twice a day, always in the morning (6:00 a.m. to 7:00 a.m.) and afternoon (12:00 p.m. to 1:00 p.m.) shifts, and were used to calculate the Globe Temperature and Humidity Index (GTHI). Supplementation did not influence the physiological variables of thermoregulation (p > 0.05). However, there were differences in the GTHI between the shifts, with higher means in the afternoon shift, especially in the less rainy period of the year, where the GTHI reached 92.06 ± 2.74 (p < 0.05). In all periods of the year, the mean values of RT, RR and BST were higher in the afternoon shift (p > 0.05). The respiratory rate (RR) is associated with the annual seasonality of the thermal waters, with higher averages in the afternoons of the rainy season. The positive correlation for rectal temperature, respiratory rate and body surface temperature indicated that buffaloes respond to thermal elevations in the atmosphere (afternoon period) and, consequently, reflect on the GTHI. Supplementation does not influence thermoregulation; the changes observed occurred in response to the region's thermal and rainfall conditions (mainly in the afternoon shift), with higher GTHI values.

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Objetivo: Determinar la relación de los planos anatómicos del cristalino con la posición real de la lente intraocular en pacientes con diagnóstico de catarata atendidos en el Centro de Microcirugía Ocular del Instituto Cubano de Oftalmología durante el período de enero del 2018 a enero 2021. Métodos: Se realizó un estudio observacional, descriptivo, prospectivo longitudinal en 89 ojos de 67 pacientes operados de catarata con implante de lente intraocular (LIO) por técnica de facoemulsificación. Se empleó para el cálculo del poder de la lente el IOL Master 700 y la fórmula de SRK/T. Se utilizó la imagen de OCT ofrecida por el IOL Máster 700 para determinar el plano ecuatorial y plano central del cristalino, así como la posición real de la lente intraocular. Resultados: Predominó el grupo de edad entre 60 - 79 años, el sexo femenino representó el 53 por ciento. Los ojos tamaño promedio y las medidas biométricas oculares en valores promedios estándar fueron los más representativos. El plano ecuatorial mostró menos diferencia con la posición real de la lente intraocular en comparación con la diferencia evidenciada entre el plano central y la posición real de la lente. La adecuada posición del lente intraocular calculado en la bolsa capsular independiente a la longitud axial, permitió obtener un resultado refractivo en correspondencia al esperado previo a la cirugía. Conclusión: Los parámetros anatómicos del cristalino (plano ecuatorial, plano central) constituyen variables importantes a tener en cuenta para el desarrollo y perfeccionamiento de las fórmulas para el cálculo del lente intraocular(AU)

Purpose: To determine the relationship of the anatomical planes of the crystalline lens with the actual position of the intraocular lens in patients with a diagnosis of cataract seen at the Ocular Microsurgery Center of the Cuban Institute of Ophthalmology during the period January 2018 and January 2021. Methods: An observational, descriptive, prospective longitudinal study was performed in 89 eyes of 67 patients operated on for cataract with intraocular lens implantation (IOL) by phacoemulsification technique. The IOL Master 700 and the SRK/T formula were used to calculate lens power. The OCT image provided by the IOL Master 700 was used to determine the equatorial plane and central plane of the crystalline lens, as well as the actual position of the intraocular lens. Results: The age group 60-79 years was predominant, female gender represented 53 percent. Average eye size and ocular biometric measurements in standard average values were the most representative. The equatorial plane showed less difference with the actual intraocular lens position compared to the difference evidenced between the central plane and the actual lens position. The adequate position of the intraocular lens calculated in the capsular bag independent to the axial length, allowed to obtain a refractive result in correspondence to the one expected before surgery. Conclusion: The anatomical parameters of the crystalline lens (equatorial plane, central plane) are important variables to be taken into account for the development and improvement of the formulas for the calculation of the intraocular lens(AU)

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The archipelago of Fernando de Noronha (FN) is located in the Equatorial South Atlantic Ocean, at 375 km off the northeastern coast of Brazil. Its endemic vertebrate land fauna is restricted to only six species, and three main hypotheses have been proposed to explain their presence in the archipelago. These hypotheses suggest FN had alternative biogeographic connections with: 1) the West Indies; 2) the South America mainland; or 3) Africa. Here, we evaluate for the first time the phylogenetic position of Amphisbaena ridleyi within the diversity of Amphisbaenia, and we infer the biogeographic processes that explain its presence in FN and its relationship with amphisbaenids from the West Indies. We analyzed a comprehensive multilocus dataset for Amphisbaenidae using maximum likelihood and time-calibrated Bayesian phylogenetic approaches. Based on our time-calibrated tree, we tested different biogeographic scenarios through historical biogeographic analyses. Our phylogenetic results for the high-level relationships of Amphisbaenia can be parenthetically summarized as (Rhineuridae, (Blanidae, (Bipedidae, (Cadeidae, (Trogonophidae, (Amphisbaenidae))))). Nine highly supported groups of species were recovered among the mainland South American amphisbaenids (SAA), whereas two phylogenetically distant groups of species were inferred for the West Indies: 1) WIC01, an Oligocene lineage present in Cuba and Hispaniola, which is the sister group of all other SAA groups; and 2) WIC02, a Miocene lineage that is restricted to southern Hispaniola and is closely related to Am. ridleyi. We estimated two events of transatlantic dispersal of amphisbaenians from Africa to West Indies: the dispersal of Cadeidae during the Middle Eocene, and the dispersal of the ancestor of Amphisbaena during the transition Eocene/Oligocene. These events were likely affected by the North Equatorial and South Equatorial currents, respectively, which have been flowing westwards since the Paleocene. The ancestral cladogenesis of Amphisbaena during the Late Oligocene is likely related to overwater dispersal events, or alternatively can be associated with the fragmentation of GAARlandia, when WIC01 was isolated in the West Indies, while the remaining groups of Amphisbaena diversified throughout the South American continent. During the Late Miocene, the ancestor of WIC02 dispersed from northern South America to the West Indies, while Am. ridleyi dispersed from the same region to FN. The overwater dispersal of WIC02 was driven by the North Brazilian Current and the dispersal of Am. ridleyi was likely influenced by the periodic shifts in direction and strength estimated for the North Equatorial Counter-Current during the Late Miocene.

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The archipelago of Fernando de Noronha (FN) is located in the Equatorial South Atlantic Ocean, at 375 km off the northeastern coast of Brazil. Its endemic vertebrate land fauna is restricted to only six species, and three main hypotheses have been proposed to explain their presence in the archipelago. These hypotheses suggest FN had alternative biogeographic connections with: 1) the West Indies; 2) the South America mainland; or 3) Africa. Here, we evaluate for the first time the phylogenetic position of Amphisbaena ridleyi within the diversity of Amphisbaenia, and we infer the biogeographic processes that explain its presence in FN and its relationship with amphisbaenids from the West Indies. We analyzed a comprehensive multilocus dataset for Amphisbaenidae using maximum likelihood and time-calibrated Bayesian phylogenetic approaches. Based on our time-calibrated tree, we tested different biogeographic scenarios through historical biogeographic analyses. Our phylogenetic results for the high-level relationships of Amphisbaenia can be parenthetically summarized as (Rhineuridae, (Blanidae, (Bipedidae, (Cadeidae, (Trogonophidae, (Amphisbaenidae))))). Nine highly supported groups of species were recovered among the mainland South American amphisbaenids (SAA), whereas two phylogenetically distant groups of species were inferred for the West Indies: 1) WIC01, an Oligocene lineage present in Cuba and Hispaniola, which is the sister group of all other SAA groups; and 2) WIC02, a Miocene lineage that is restricted to southern Hispaniola and is closely related to Am. ridleyi. We estimated two events of transatlantic dispersal of amphisbaenians from Africa to West Indies: the dispersal of Cadeidae during the Middle Eocene, and the dispersal of the ancestor of Amphisbaena during the transition Eocene/Oligocene. These events were likely affected by the North Equatorial and South Equatorial currents, respectively, which have been flowing westwards since the Paleocene. The ancestral cladogenesis of Amphisbaena during the Late Oligocene is likely related to overwater dispersal events, or alternatively can be associated with the fragmentation of GAARlandia, when WIC01 was isolated in the West Indies, while the remaining groups of Amphisbaena diversified throughout the South American continent. During the Late Miocene, the ancestor of WIC02 dispersed from northern South America to the West Indies, while Am. ridleyi dispersed from the same region to FN. The overwater dispersal of WIC02 was driven by the North Brazilian Current and the dispersal of Am. ridleyi was likely influenced by the periodic shifts in direction and strength estimated for the North Equatorial Counter-Current during the Late Miocene.

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The objective of this study was to analyse the feeding habits and trophic interactions between four oceanic predatory fish around the Fernando de Noronha Archipelago (FNA), Brazil, in the western equatorial Atlantic (3.86°S/32.42°W), internationally recognized as an environment of high economic and ecological value. For this purpose, biological samples of yellowfin tuna (Thunnus albacares), wahoo (Acanthocybium solandri), barracuda (Sphyraena barracuda) and dolphinfish (Coryphaena hippurus) were collected for stomach content and stable isotope analysis. Values of the index of relative importance revealed varied diets, with a strong presence of teleost fishes (Diodontidae and Exocoetidae) for all species, with yellowfin tuna having a greater diversity of food items. Despite being generalists/opportunists, the feeding strategy of these predators showed a tendency towards a specialized diet in the use of the available resources around the FNA. They presented a narrow trophic niche width (Levin's index, Bi < 0.6) and low overlap between species, except between barracuda and wahoo (MacArthur and Levin's, R0  = 0.72). Isotopic compositions had broad values of δ13 C and δ15 N, and were significantly different between species. Our results provide information about the four species' trophic organization and suggest that the predators avoid competition by preying on different prey, thus allowing their coexistence.

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The reef system off the Amazon River mouth extends from Amapá state to Maranhão state along the Brazilian Equatorial Margin, encompassing more than 10,000 km2 of rhodolith beds and high-relief hard structures on the outer shelf and upper slope. This unique hard bottom mosaic is remarkable for being influenced by the turbid and hyposaline plume from the world's largest river, and also for representing a connectivity corridor between the Caribbean and Brazil. Bryozoans were recently recognized as major reef builders in the Southwestern Atlantic, but their diversity off the Amazon River mouth remained unknown. Here, we report on recent collections obtained from 23 to 120 m depth in Northern Brazil. Sixty-five bryozoan taxa were characterized using scanning electron microscopy, including 57, five and three taxa of Cheilostomatida, Cyclostomatida and Ctenostomatida, respectively. Cribrilaria smitti and three genera (Cranosina, Glabrilaria and Thornelya) are new records for Brazil, and 13 new species are herein described: Antropora cruzeiro n. sp., Cranosina gilbertoi n. sp., Cribrilaria lateralis n. sp., Crisia brasiliensis n. sp., Glabrilaria antoniettae n. sp., Micropora amapaensis n. sp., Parasmittina amazonensis n. sp., Plesiocleidochasma arcuatum n. sp., Poricella bifurcata n. sp., Pourtalesella duoavicularia n. sp., Stephanollona domuspusilla n. sp., Therenia dianae n. sp., and Thornelya atlanticoensis n. sp. Our results highlight the biodiversity significance of the Amazon reefs and the need for more comprehensive sampling to clarify the role of bryozoans in modern turbid-zone reefs and rhodolith beds.

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Introducción: El sarcoma de Kaposi es una neoplasia oportunista asociada a la inmunodepresión causada por VIH, que se relaciona con la infección por VHH tipo 8. Objetivo: Describir la presentación del sarcoma de Kaposi en personas que viven con VIH en Guinea Ecuatorial. Métodos: Se realizó un estudio descriptivo de carácter retrospectivo para identificar la prevalencia y las características epidemiológicas y clínicas del sarcoma de Kaposi en las personas que viven con VIH que acuden a las unidades de referencia para el manejo de casos en Guinea Ecuatorial. Se revisaron las historias clínicas de una muestra aleatoria y representativa de 338 pacientes del grupo que ha recibido tratamiento en las unidades de referencia para enfermedades infecciosas de Bata, desde enero de 2007 a febrero de 2012. Resultados: Se identificaron 40 pacientes diagnosticados de sarcoma de Kaposi (prevalencia del 11, 83 por ciento). La mediana de la edad al diagnóstico de sarcoma de Kaposi fue de 43 años, siendo la ratio del sexo de 1/1. La media de linfocitos CD4 al diagnóstico fue de 166 (rango 21-375) y la frecuencia de afectación oral fue de 45 por ciento. En la mayoría de los pacientes (94,6 por ciento) la observación del sarcoma de Kaposi fue anterior al inicio del tratamiento antirretroviral. Las cifras de linfocitos T CD4/mm3 inferiores a 100 aparecían sobre todo en pacientes menores de 30 años, y esto era especialmente frecuente en el grupo de mujeres (OR 11, p <0,04, Ic 95 por ciento 0,8-148). Conclusiones: El sarcoma de Kaposi es una neoplasia prevalente en personas que viven con VIH seguidas en las unidades de referencia en Guinea Ecuatorial. En mujeres menores de 30 años podría existir un diagnóstico tardío(AU)

Introduction: Kaposi sarcoma is an opportunistic neoplasm associated to the immunosuppression caused by HIV and related to infection by HHV-8. Objective: Describe the presentation of Kaposi sarcoma in people living with HIV in Equatorial Guinea. Methods: A retrospective descriptive study was conducted to identify the prevalence and the clinical and epidemiological characteristics of Kaposi sarcoma in people living with HIV attending reference units for the management of cases in Equatorial Guinea. A review was carried out of the medical records of a random sample representative of 338 patients from the group receiving treatment at Bata reference unit for infectious diseases from January 2007 to February 2012. Results: A total 40 patients diagnosed with Kaposi sarcoma were identified (prevalence of 11,83 percent). Mean age at Kaposi sarcoma diagnosis was 43 years, with a 1/1 sex ratio. The mean CD4 lymphocyte count at diagnosis was 166 (range 21-375), whereas the frequency of oral damage was 45 percent. In most patients (94.6 percent) detection of Kaposi sarcoma was prior to the start of antiretroviral therapy. CD4 T lymphocyte levels / mm3 below 100 were mainly found in patients aged under 30 years, a fact particularly frequent among women (OR 11, p< 0.04, CI 95% 0.8-148). Conclusions: Kaposi sarcoma is a neoplasm prevailing in people living with HIV who attend reference units in Equatorial Guinea. Late diagnosis could exist among women aged under 30 years(AU)

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Resumen Se registra Neoraimondia arequipensis subesp. gigantea en los bosques secos de Tumbes, ampliándose su distribución geográfica en el norte del Perú. Se realizó la identificación fenotípica de 70 individuos y genotípica basada en la secuenciación del gen matK (Maturase K gene). El hábitat de esta especie se caracteriza por la presencia de suelo de tipo pedregoso y rocoso, ubicados aledaños a zonas de quebradas y altitudes entre 20 a 60 m. Además, se registran observaciones de interacciones biológicas de este cactus con fauna y flora endémica del departamento de Tumbes.

Abstract Neoraimondia arequipensis subsp. gigantea is registered in the dry forests of Tumbes, expanding its geographical distribution in northern Peru, based on the phenotypic identification of 70 individuals and genotypic by sequencing the matK gene (Maturase K gene). The habitat of this species is characterized by the presence of stony and rocky soil, located adjacent to areas of ravines and altitudes between 20 to 60 meters above sea level. In addition, we include the record of biological interactions of this cactus with endemic fauna and flora of the department of Tumbes.

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In mammals, many melatonin biological functions are mediated through its interaction with the membrane receptors MT1 and MT2. We have previously reported their presence in ram spermatozoa from males located in temperate climates, but there is no information on their presence in spermatozoa from rams in areas with an equatorial photoperiod (12L:12D). Thus, we have investigated the existence and cellular distribution of melatonin receptors in spermatozoa from three sheep breeds in Colombia (Colombian Creole, Hampshire, and Romney Marsh) during dry and rainy seasons, using indirect immunofluorescence and western blot. Our results indicated the presence of melatonin receptors in spermatozoa from these rams, and that their distribution differs from that previously found in spermatozoa from rams in temperate climates. Moreover, two new immunotypes of MT2 were identified: type N, with staining only in the neck, and type E with a band of immunofluorescence in the upper part of the post-acrosome and the apical edge. Likewise, differences between breeds and climate seasons were detected for both receptors. However, densitometry analysis of western blot bands only revealed differences between seasons in the Creole rams for MT1 and the Romney Marsh rams for MT2, whereas differences between breeds were only detected for MT2. It could be inferred that melatonin receptors in rams subjected to an equatorial photoperiod might be more closely related to sperm quality than seasonal control. Therefore, the presence of these receptors suggests that melatonin could be a useful tool to increase the fertility of rams located in tropical or equatorial climates.

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Coral communities worldwide are progressively more stressed by anthropogenic activities that increase fluxes of sediment and other pollutants to nearshore areas. Some nearshore coral reef environments off the Equatorial margin of Brazil, including Pirangi and Maracajaú, Rio Grande do Norte (RN, Brazil), seem to be under human-induced stress. However, the horizontal extent of this stress, its effects, and assessment of the environmental response depend on the hydrodynamic conditions (circulation and deposition patterns), sedimentary facies, and the availability of biological indicators. We investigate two Brazilian live reefal corals' communities by examining seven photosymbiont-bearing species (PSB) of Foraminifera, Amphisorus hemprichii, Amphistegina gibbosa, Archaias angulatus, Borelis schlumbergeri, Heterostegina antillarum, Peneroplis carinatus, and Laevipeneroplis proteus, using numerical analysis FORAM Index (FI), grain size, and particulate organic and inorganic carbonate. Here, we show that coarse sand fraction followed by fine sand fraction and high hydrodynamics plays an important role in transportation and deposition of sediments and foraminiferal tests in the study area. According to FI results, conditions at Pirangi are not suitable for coral reef growth. Maracajaú has sites that are suitable for coral reef growth and sites where coral could not survive after a stress event. We need long-term assessments to improve our knowledge of the distribution and ecological importance of Brazilian reef-dwelling foraminifers and to extend the application of FI to monitoring management plans of the Pirangi and Maracajaú National Marine Parks by providing a first insight into the biodiversity patterns and a reliable tool of the reconstruction of paleo reef health.

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We provide a baseline assessment of the density and types of microplastics in the western equatorial Atlantic. The highest microplastics density was found in coastal stations near urbanized sites, large tropical estuaries, and fishing grounds. With regard to microplastics composition, most of the identified particles were fibers/filaments, styrofoam, hard and soft plastic, paint, and glass/acrylic. Fibers/filaments were the most abundant (~80%) and occurred at all stations, in both types of mesh nets. Hard plastic particles were frequent (78%) only in the 120 µm mesh net. The mean density recorded in the 120 µm mesh net was about seven times greater than that in the 300 µm mesh net, suggesting that the larger mesh size net did not lead to an accurate description of microplastics density in the pelagic environment or the degree of risk to which organisms are exposed.

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The semi-arid region of Northeast Brazil (NEB) experiences severe droughts during El Niño Southern Oscillation (ENSO) years, with major impacts on the dynamics of the native vegetation (Caatinga). However, the effect of these droughts on carbon cycling is not well understood. Here, a numerical model is used to investigate the influence of variations in Pacific and Atlantic sea surface temperatures (SST) on drought and carbon dynamics of the Caatinga during past ENSO events. We demonstrate that precipitation reductions in the Caatinga have a strong influence on vegetation dynamics, with net primary production (NPP) remaining low throughout the droughts. Furthermore, the Caatinga acts as a carbon sink, even in years of severe drought. However, net ecosystem exchange (NEE) is lower in years of low NPP rates, resulting in long periods with limited ecosystem activity. The SST patterns indicate that extreme vegetation changes in the Caatinga are associated with the combination of ENSO events and North Atlantic SST warming.

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Re(I) complexes have exposed highly suitable properties for cellular imaging (especially for fluorescent microscopy) such as low cytotoxicity, good cellular uptake, and differential staining. These features can be modulated or tuned by modifying the ligands surrounding the metal core. However, most of Re(I)-based complexes have been tested for non-walled cells, such as epithelial cells. In this context, it has been proposed that Re(I) complexes are inefficient to stain walled cells (i.e., cells protected by a rigid cell wall, such as bacteria and fungi), presumably due to this physical barrier hampering cellular uptake. More recently, a series of studies have been published showing that a suitable combination of ligands is useful for obtaining Re(I)-based complexes able to stain walled cells. This review summarizes the main characteristics of different fluorophores used in bioimage, remarking the advantages of d6-based complexes, and focusing on Re(I) complexes. In addition, we explored different structural features of these complexes that allow for obtaining fluorophores especially designed for walled cells (bacteria and fungi), with especial emphasis on the ligand choice. Since many pathogens correspond to bacteria and fungi (yeasts and molds), and considering that these organisms have been increasingly used in several biotechnological applications, development of new tools for their study, such as the design of new fluorophores, is fundamental and attractive.

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The present paper aimed to show the thermoregulatory responses of locally adapted Morada Nova sheep with different coat colors that were exposed to direct solar radiation in an equatorial semiarid region. Animals were classified into four groups according to the coat color as follows: (1) dark red, (2) intermediate red, (3) light red, and (4) white coats. Forty Morada Nova ewes were observed in for 7 consecutive months. The experimental variables measured were rectal temperature (RT), skin surface temperature (ST), respiratory rate (RR), skin surface evaporation (CE), respiratory evaporation (RE), and heat exchange by convection (HC) and radiation (R). Data were collected from 1100 to 1400 h after the animals were exposed to 30 min direct sunlight. The results showed that all groups maintained homeothermy. The RR was higher in the animals of groups 1 to 3, which also showed higher values for ST when compared to the white-coated animals. Sensible heat exchange mechanisms were not important for heat loss, and R was a significant source of heat gain from the environment for the animals. Groups 1, 2, and 3 used RR more intensely than group 4 (P value = 0.001); however, CE was higher for the white-coated animals. It was concluded that Morada Nova sheep are well adapted to the semiarid environment, regardless of coat color.

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Tropical ecosystems play a key role in many aspects of Earth system dynamics currently of global concern, including carbon sequestration and biodiversity. To accurately understand complex tropical systems it is necessary to parameterise key ecological aspects, such as rates of change (RoC), species turnover, dynamism, resilience, or stability. To obtain a long-term (>50 years) perspective on these ecological aspects we must turn to the fossil record. However, compared to temperate zones, collecting continuous sedimentary archives in the lowland tropics is often difficult due to the active landscape processes, with potentially frequent volcanic, tectonic, and/or fluvial events confounding sediment deposition, preservation, and recovery. Consequently, the nature, and drivers, of vegetation dynamics during the last glacial are barely known from many non-montane tropical landscapes. One of the first lowland Amazonian locations from which palaeoecological data were obtained was an outcrop near Mera (Ecuador). Mera was discovered, and analysed, by Paul Colinvaux in the 1980s, but his interpretation of the data as indicative of a forested glacial period were criticised based on the ecology and age control. Here we present new palaeoecological data from a lake located less than 10 km away from Mera. Sediment cores raised from Laguna Pindo (1250 masl; 1°27'S, 78°05'W) have been shown to span the late last glacial period [50-13 cal kyr BP (calibrated kiloyears before present)]. The palaeoecological information obtained from Laguna Pindo indicate that the region was characterised by a relatively stable plant community, formed by taxa nowadays common at both mid and high elevations. Miconia was the dominant taxon until around 30 cal kyr BP, when it was replaced by Hedyosmum, Asteraceae and Ilex among other taxa. Heat intolerant taxa including Podocarpus, Alnus, and Myrica peaked around the onset of the Last Glacial Maximum (c. 21 cal kyr BP). The results obtained from Laguna Pindo support Colinvaux's hypothesis that glacial cooling resulted in a reshuffling of taxa in the region but did not lead to a loss of the forest structure. Wide tolerances of the plant species occurring to glacial temperature range and cloud formation have been suggested to explain Pindo forest stability. This scenario is radically different than the present situation, so vulnerability of the tropical pre-montane forest is highlighted to be increased in the next decades.

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Los páramos son ecosistemas que se caracterizan por una alta humedad relativa, alta frecuencia de niebla y por tener una vegetación arbustiva y herbácea, adaptada a las condiciones de alta montaña. En condiciones naturales estos ecosistemas presentan una oferta hídrica alta, entre otros servicios ecosistémicos; sin embargo, esto cambia cuando son degradados. A pesar de su importancia son ecosistemas que han sido modificados por el hombre, la mayoría aún sin haber sido estudiados. Este documento presenta los resultados de una investigación realizada en tres páramos en Colombia, en la cual, se evalúa su funcionamiento hidrológico y la capacidad de recuperación, una vez han sido alterados; para esto, se estudió el clima, la hidrología y los suelos. Los resultados indican que estos ecosistemas tienen condiciones climáticas desiguales, que determinan su rendimiento y regulación hídrica; con diferencias en las propiedades hidrofísicas del suelo y contenido de materia orgánica, lo que determina diferencias en su capacidad para retener la humedad y la disponibilidad de agua para las plantas. Estos resultados indican que los páramos, con un grado bajo de disturbio, presentan un alto rendimiento y buena regulación hídrica; pero igual que los páramos intervenidos, recuperan el estado natural de las propiedades del suelo y, consecuentemente, su funcionamiento hidrológico, aún en pocas décadas.

Páramos are equatorial alpine ecosystems characterized by a high air humidity, frequency of fog and the presence of shrub and herbaceous vegetation adapted to the specific equatorial alpine conditions. Under natural conditions these ecosystems present a high water yield, among other ecosystem services, however, this changes when they are degraded. Despite their importance, they are ecosystems that have been modified by man, most of them even without having been studied. This paper presents the results of a hydrological research carried out in three páramos in Colombia, which evaluates their hydrological functioning and their capacity for recovery once they are altered. Therefore, we studied their climate, hydrology, and soils properties. Results indicate that these ecosystems have different climatic conditions, which determine their water yield and water regulation. Differences in the hydro-physical properties of soils and organic matter content, which determine differences in their capacity to retain water and on the magnitude of the water available for plants. These results indicate that undisturbed páramos or with a low degree of disturbance present high water yield and good water regulation; and intervened páramos can recover the natural conditions of soil properties, and consequently their hydrological functioning, even in a few decades.

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The genetic and morphometric population structures of the semiterrestrial crab Armases angustipes from along the Brazilian coast were examined. The influence of the Central South Equatorial Current on larval dispersal of A. angustipes also was evaluated. Six populations were sampled from estuarine areas in São Luis do Maranhão, Maranhão; Natal, Rio Grande do Norte; Maceió, Alagoas; Ilhéus, Bahia; Aracruz, Espírito Santo; and Guaratuba, Paraná. Patterns of genetic differentiation were assessed using DNA sequence data corresponding to parts of the mitochondrial cytochrome c oxidase subunit 1. Geometric morphometric techniques were used to evaluate morphological variation in shape and size of the carapace and right cheliped propodus. Our results revealed low genetic variability and lack of phylogeographic structure; geometric morphometrics showed statistically significant morphological differentiation and geographic structuring. Our data indicate the absence of possible barriers to gene flow for this mobile species, and no clear correlation of morphological or genetic variation with ocean currents and/or geographic distance. Our results also suggest that historical geological and climatological events and/or possible bottleneck effects influenced the current low genetic variability among the populations of A. angustipes.

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RESUMO

A presença de anastomoses vasculares placentárias nas gestações gemelares monocoriônicas favorece o surgimento de complicações graves como a Síndrome de Transfusão Feto-Fetal (STFF) e a Sequência Anemia-Policitemia em Gêmeos (TAPS). STFF e TAPS são ambas formas crônicas de transfusão feto-fetal. TAPS, descrita em 2007, é caracterizada por anemia crônica no gêmeo doador e policitemia no gêmeo receptor, na ausência de discordância no volume de líquido amniótico, característica da STFF clássica. O diagnóstico pode ser feito pré- e pós-natal. O critério diagnóstico pré-natal é baseado na discordância intergemelar da medida do Doppler do pico de velocidade sistólica da artéria cerebral média (PSV-ACM). O diagnóstico pós-natal é baseado na grande diferença da hemoglobina intergemelar, ao nascimento, e reticulocitose no gêmeo doador.(AU)

The presence of placental vascular anastomoses in monochorionic twins favors the development of several complications like Twin-Twin Transfusion Syndrome (TTTS) and Twin Anemia-Polycythemia Sequence (TAPS). TTTS and TAPS are both chronic forms of fetofetal transfusion. TAPS, described on 2007, is characterized by chronic anemia in the donor twin and polycythemia in the recipient twin, in the absence of amniotic fluid volume discordances, characteristic of classical TTTS. The diagnostic can be made pree posnatally. The prenatal diagnostic criteria is based on the inter-twin discordance in Doppler measurement of peak systolic velocity in the middle cerebral artery (MCA-PSV). The postnatal diagnosis is based on large intertwin hemoglobin difference at birth and retoculocytosis in the donor twin.(AU)

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